Sample records for modeling cumulative evidence

  1. Integrating Etiological Models of Social Anxiety and Depression in Youth: Evidence for a Cumulative Interpersonal Risk Model (United States)

    Epkins, Catherine C.; Heckler, David R.


    Models of social anxiety and depression in youth have been developed separately, and they contain similar etiological influences. Given the high comorbidity of social anxiety and depression, we examine whether the posited etiological constructs are a correlate of, or a risk factor for, social anxiety and/or depression at the symptom level and the…

  2. Predicting Cumulative Incidence Probability: Marginal and Cause-Specific Modelling

    DEFF Research Database (Denmark)

    Scheike, Thomas H.; Zhang, Mei-Jie


    cumulative incidence probability; cause-specific hazards; subdistribution hazard; binomial modelling......cumulative incidence probability; cause-specific hazards; subdistribution hazard; binomial modelling...

  3. Cumulative evidence of the low reliability of frozen/thawed pig skin as a model for in vitro percutaneous permeation testing. (United States)

    Sintov, Amnon C


    Porcine skin has frequently been used as a model in in vitro permeation studies being considered as an excellent alternative for human skin due to biochemical similarities. The use of frozen skin after thawing is particularly more convenient for these studies since it is available whenever needed. Even though several researchers have noticed that freezing and then thawing the tissue result in enhancement of drug permeation, many published articles have still described studies using frozen pig skin for bioequivalence and transdermal evaluation of drug products. The aim of this commentary article is therefore to explicitly demonstrate, according to our experience, the low-reliability of the convenient protocol of freezing pig skin for in vitro percutaneous studies. It has been shown in three separate studies using three different drugs that frozen/thawed pig skin had a higher permeability to drugs compared to that obtained by using fresh skin. The results have further demonstrated that the abnormal permeability through frozen pig skin is independent of the effect of different formulations, placing a question mark on the validity of the not freshly-used porcine skin for in vitro penetration studies. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. The proportional odds cumulative incidence model for competing risks

    DEFF Research Database (Denmark)

    Eriksson, Frank; Li, Jianing; Scheike, Thomas


    We suggest an estimator for the proportional odds cumulative incidence model for competing risks data. The key advantage of this model is that the regression parameters have the simple and useful odds ratio interpretation. The model has been considered by many authors, but it is rarely used in pr...

  5. A modelling framework for MSP-oriented cumulative effects assessment


    Stefano Menegon; Daniel Depellegrin; Giulio Farella; Elena Gissi; Michol Ghezzo; Alessandro Sarretta; Chiara Venier; Andrea Barbanti


    This research presents a comprehensive Cumulative Eects Assessment (CEA) based on the Tools4MSP modelling framework tested for the Italian Adriatic Sea. The CEA incorporates ve methodological advancements: (1) linear and non-linear ecosystem response to anthropogenic pressures/effects, (2) modelling of additive, dominant and antagonist stressor effects, (3) implementation of a convolution distance model for stressor dispersion modelling, (4) application of a CEA backsourcing (CEA-B) model to ...

  6. Evolutionary neural network modeling for software cumulative failure time prediction

    International Nuclear Information System (INIS)

    Tian Liang; Noore, Afzel


    An evolutionary neural network modeling approach for software cumulative failure time prediction based on multiple-delayed-input single-output architecture is proposed. Genetic algorithm is used to globally optimize the number of the delayed input neurons and the number of neurons in the hidden layer of the neural network architecture. Modification of Levenberg-Marquardt algorithm with Bayesian regularization is used to improve the ability to predict software cumulative failure time. The performance of our proposed approach has been compared using real-time control and flight dynamic application data sets. Numerical results show that both the goodness-of-fit and the next-step-predictability of our proposed approach have greater accuracy in predicting software cumulative failure time compared to existing approaches

  7. Analysis of sensory ratings data with cumulative link models

    DEFF Research Database (Denmark)

    Christensen, Rune Haubo Bojesen; Brockhoff, Per B.


    Examples of categorical rating scales include discrete preference, liking and hedonic rating scales. Data obtained on these scales are often analyzed with normal linear regression methods or with omnibus Pearson chi2 tests. In this paper we propose to use cumulative link models that allow for reg...

  8. Preference, resistance to change, and the cumulative decision model. (United States)

    Grace, Randolph C


    According to behavioral momentum theory (Nevin & Grace, 2000a), preference in concurrent chains and resistance to change in multiple schedules are independent measures of a common construct representing reinforcement history. Here I review the original studies on preference and resistance to change in which reinforcement variables were manipulated parametrically, conducted by Nevin, Grace and colleagues between 1997 and 2002, as well as more recent research. The cumulative decision model proposed by Grace and colleagues for concurrent chains is shown to provide a good account of both preference and resistance to change, and is able to predict the increased sensitivity to reinforcer rate and magnitude observed with constant-duration components. Residuals from fits of the cumulative decision model to preference and resistance to change data were positively correlated, supporting the prediction of behavioral momentum theory. Although some questions remain, the learning process assumed by the cumulative decision model, in which outcomes are compared against a criterion that represents the average outcome value in the current context, may provide a plausible model for the acquisition of differential resistance to change. © 2018 Society for the Experimental Analysis of Behavior.

  9. Modelling the evolution and diversity of cumulative culture. (United States)

    Enquist, Magnus; Ghirlanda, Stefano; Eriksson, Kimmo


    Previous work on mathematical models of cultural evolution has mainly focused on the diffusion of simple cultural elements. However, a characteristic feature of human cultural evolution is the seemingly limitless appearance of new and increasingly complex cultural elements. Here, we develop a general modelling framework to study such cumulative processes, in which we assume that the appearance and disappearance of cultural elements are stochastic events that depend on the current state of culture. Five scenarios are explored: evolution of independent cultural elements, stepwise modification of elements, differentiation or combination of elements and systems of cultural elements. As one application of our framework, we study the evolution of cultural diversity (in time as well as between groups).

  10. Model-checking techniques based on cumulative residuals. (United States)

    Lin, D Y; Wei, L J; Ying, Z


    Residuals have long been used for graphical and numerical examinations of the adequacy of regression models. Conventional residual analysis based on the plots of raw residuals or their smoothed curves is highly subjective, whereas most numerical goodness-of-fit tests provide little information about the nature of model misspecification. In this paper, we develop objective and informative model-checking techniques by taking the cumulative sums of residuals over certain coordinates (e.g., covariates or fitted values) or by considering some related aggregates of residuals, such as moving sums and moving averages. For a variety of statistical models and data structures, including generalized linear models with independent or dependent observations, the distributions of these stochastic processes tinder the assumed model can be approximated by the distributions of certain zero-mean Gaussian processes whose realizations can be easily generated by computer simulation. Each observed process can then be compared, both graphically and numerically, with a number of realizations from the Gaussian process. Such comparisons enable one to assess objectively whether a trend seen in a residual plot reflects model misspecification or natural variation. The proposed techniques are particularly useful in checking the functional form of a covariate and the link function. Illustrations with several medical studies are provided.

  11. Flexible parametric modelling of cause-specific hazards to estimate cumulative incidence functions (United States)


    Background Competing risks are a common occurrence in survival analysis. They arise when a patient is at risk of more than one mutually exclusive event, such as death from different causes, and the occurrence of one of these may prevent any other event from ever happening. Methods There are two main approaches to modelling competing risks: the first is to model the cause-specific hazards and transform these to the cumulative incidence function; the second is to model directly on a transformation of the cumulative incidence function. We focus on the first approach in this paper. This paper advocates the use of the flexible parametric survival model in this competing risk framework. Results An illustrative example on the survival of breast cancer patients has shown that the flexible parametric proportional hazards model has almost perfect agreement with the Cox proportional hazards model. However, the large epidemiological data set used here shows clear evidence of non-proportional hazards. The flexible parametric model is able to adequately account for these through the incorporation of time-dependent effects. Conclusion A key advantage of using this approach is that smooth estimates of both the cause-specific hazard rates and the cumulative incidence functions can be obtained. It is also relatively easy to incorporate time-dependent effects which are commonly seen in epidemiological studies. PMID:23384310

  12. Single-Word Predictions of Upcoming Language During Comprehension: Evidence from the Cumulative Semantic Interference Task (United States)

    Kleinman, Daniel; Runnqvist, Elin; Ferreira, Victor S.


    Comprehenders predict upcoming speech and text on the basis of linguistic input. How many predictions do comprehenders make for an upcoming word? If a listener strongly expects to hear the word “sock”, is the word “shirt” partially expected as well, is it actively inhibited, or is it ignored? The present research addressed these questions by measuring the “downstream” effects of prediction on the processing of subsequently presented stimuli using the cumulative semantic interference paradigm. In three experiments, subjects named pictures (sock) that were presented either in isolation or after strongly constraining sentence frames (“After doing his laundry, Mark always seemed to be missing one…”). Naming sock slowed the subsequent naming of the picture shirt – the standard cumulative semantic interference effect. However, although picture naming was much faster after sentence frames, the interference effect was not modulated by the context (bare vs. sentence) in which either picture was presented. According to the only model of cumulative semantic interference that can account for such a pattern of data, this indicates that comprehenders pre-activated and maintained the pre-activation of best sentence completions (sock) but did not maintain the pre-activation of less likely completions (shirt). Thus, comprehenders predicted only the most probable completion for each sentence. PMID:25917550

  13. Modeling the cumulative watershed effects of forest management strategies (United States)

    R. R. Ziemer; J. Lewis; R. M. Rice; T. E. Lisle


    Abstract - There is increasing concern over the possibility of adverse cumulative watershed effects from intensive forest management. It is impractical to address many aspects of the problem experimentally because to do so would require studying large watersheds for 100 yr or more. One such aspect is the long-term effect of forest management strategies on erosion and...

  14. Error Analysis on the Estimation of Cumulative Infiltration in Soil Using Green and AMPT Model

    Directory of Open Access Journals (Sweden)

    Muhamad Askari


    Full Text Available Green and Ampt infiltration model is still useful for the infiltration process because of a clear physical basis of the model and of the existence of the model parameter values for a wide range of soil. The objective of thise study was to analyze error on the esimation of cumulative infiltration in sooil using Green and Ampt model and to design laboratory experiment in measuring cumulative infiltration. Parameter of the model was determined based on soil physical properties from laboratory experiment. Newton –Raphson method was esed to estimate wetting front during calculation using visual Basic for Application (VBA in MS Word. The result showed that  contributed the highest error in estimation of cumulative infiltration and was followed by K, H0, H1, and t respectively. It also showed that the calculated cumulative infiltration is always lower than both measured cumulative infiltration and volumetric soil water content.

  15. Analysis of modeling cumulative noise from simultaneous flights volume 1 : analysis at four national parks (United States)


    This is the first of two volumes of the report on modeling cumulative noise from simultaneous flights. This volume includes: an overview of the time compression algorithms used to model simultaneous aircraft; revised summary of a preliminary study (w...

  16. QSAR modeling of cumulative environmental end-points for the prioritization of hazardous chemicals. (United States)

    Gramatica, Paola; Papa, Ester; Sangion, Alessandro


    The hazard of chemicals in the environment is inherently related to the molecular structure and derives simultaneously from various chemical properties/activities/reactivities. Models based on Quantitative Structure Activity Relationships (QSARs) are useful to screen, rank and prioritize chemicals that may have an adverse impact on humans and the environment. This paper reviews a selection of QSAR models (based on theoretical molecular descriptors) developed for cumulative multivariate endpoints, which were derived by mathematical combination of multiple effects and properties. The cumulative end-points provide an integrated holistic point of view to address environmentally relevant properties of chemicals.

  17. Using fractional polynomials to model the effect of cumulative duration of exposure on outcomes: applications to cohort and nested case-control designs. (United States)

    Austin, Peter C; Park-Wyllie, Laura Y; Juurlink, David N


    Determining the nature of the relationship between cumulative duration of exposure to an agent and the hazard of an adverse outcome is an important issue in environmental and occupational epidemiology, public health and clinical medicine. The Cox proportional hazards regression model can incorporate time-dependent covariates. An important class of continuous time-dependent covariates is that denoting cumulative duration of exposure. We used fractional polynomial methods to describe the association between cumulative duration of exposure and adverse outcomes. We applied these methods in a cohort study to examine the relationship between cumulative duration of use of the antiarrhythmic drug amiodarone and the risk of thyroid dysfunction. We also used these methods with a conditional logistic regression model in a nested case-control study to examine the relationship between cumulative duration of use of bisphosphonate medication and the risk of atypical femur fracture. Using a cohort design and a Cox proportional hazards model, we found a non-linear relationship between cumulative duration of use of the antiarrhythmic drug amiodarone and the risk of thyroid dysfunction. The risk initially increased rapidly with increasing cumulative use. However, as cumulative duration of use increased, the rate of increase in risk attenuated and eventually levelled off. Using a nested case-control design and a conditional logistic regression model, we found evidence of a linear relationship between duration of use of bisphosphonate medication and risk of atypical femur fractures. Fractional polynomials allow one to model the relationship between cumulative duration of medication use and adverse outcomes. © 2014 The Authors. Pharmacoepidemiology and Drug Safety published by John Wiley & Sons, Ltd.

  18. Fast and accurate calculations for cumulative first-passage time distributions in Wiener diffusion models

    DEFF Research Database (Denmark)

    Blurton, Steven Paul; Kesselmeier, M.; Gondan, Matthias


    We propose an improved method for calculating the cumulative first-passage time distribution in Wiener diffusion models with two absorbing barriers. This distribution function is frequently used to describe responses and error probabilities in choice reaction time tasks. The present work extends ...

  19. Cumulative Risk and Impact Modeling on Environmental Chemical and Social Stressors. (United States)

    Huang, Hongtai; Wang, Aolin; Morello-Frosch, Rachel; Lam, Juleen; Sirota, Marina; Padula, Amy; Woodruff, Tracey J


    The goal of this review is to identify cumulative modeling methods used to evaluate combined effects of exposures to environmental chemicals and social stressors. The specific review question is: What are the existing quantitative methods used to examine the cumulative impacts of exposures to environmental chemical and social stressors on health? There has been an increase in literature that evaluates combined effects of exposures to environmental chemicals and social stressors on health using regression models; very few studies applied other data mining and machine learning techniques to this problem. The majority of studies we identified used regression models to evaluate combined effects of multiple environmental and social stressors. With proper study design and appropriate modeling assumptions, additional data mining methods may be useful to examine combined effects of environmental and social stressors.

  20. Modeling the Cumulative Effects of Social Exposures on Health: Moving beyond Disease-Specific Models

    Directory of Open Access Journals (Sweden)

    Heather L. White


    Full Text Available The traditional explanatory models used in epidemiology are “disease specific”, identifying risk factors for specific health conditions. Yet social exposures lead to a generalized, cumulative health impact which may not be specific to one illness. Disease-specific models may therefore misestimate social factors’ effects on health. Using data from the Canadian Community Health Survey and Canada 2001 Census we construct and compare “disease-specific” and “generalized health impact” (GHI models to gauge the negative health effects of one social exposure: socioeconomic position (SEP. We use logistic and multinomial multilevel modeling with neighbourhood-level material deprivation, individual-level education and household income to compare and contrast the two approaches. In disease-specific models, the social determinants under study were each associated with the health conditions of interest. However, larger effect sizes were apparent when outcomes were modeled as compound health problems (0, 1, 2, or 3+ conditions using the GHI approach. To more accurately estimate social exposures’ impacts on population health, researchers should consider a GHI framework.

  1. NK cells mediate the cumulative analgesic effect of electroacupuncture in a rat model of neuropathic pain. (United States)

    Gao, Yong-Hui; Wang, Jun-Ying; Qiao, Li-Na; Chen, Shu-Ping; Tan, Lian-Hong; Xu, Qiu-Ling; Liu, Jun-Ling


    Cumulating evidence has revealed the effectiveness of acupuncture therapy in relieving pain via immunoregulation. However, its underlying mechanism remains unknown. The present study was designed to determine the changes of immunogenic responses at different time-points of electroacupuncture (EA) interventions in neuropathic pain rats. The neuropathic pain model was established by ligature of the left sciatic nerve to induce chronic constriction injury (CCI). EA was applied at Zusanli (ST36) and Yanglingquan (GB34) for the EA groups. The thermal pain threshold was detected with an algesia-detector. The subgroups of plasma and splenic lymphocytes were determined via fluorescence-activated cell sorting. Specific inflammatory cytokines were assayed using an ELISA-based bead multiplex assay. The activities of splenic natural killer (NK) cells and cytotoxic T lymphocytes were detected by methyl thiazolyl tetrazolium colorimetric method. For confirming the involvement of NK cell in EA-analgesia, anti-asialo-ganglio-N-tetraosylceramide (anti-asialo-GM1) antibody was given to CCI rats before EA. Following CCI, the thermal pain threshold of the affected hind footpad was significantly decreased, and increased from the 3rd day to the 12th day after EA interventions, presenting a time-dependent tendency from the 5th day on. From day 3 to 5 of EA interventions, the percentages and activity of splenic NK cells, concentrations of splenic interleukin-2 (IL-2) and beta-endorphin (β-EP) were significantly increased. Meanwhile, the concentrations of plasma IL-2, IL-1β and gamma-interferon (IFN-γ) were significantly decreased and returned to the normal level on day 12 following EA. Plasma transforming growth factor-β (TGF-β) levels were considerably upregulated on day 5 and 12 following EA. The CD4+/CD8+ T cell ratio was markedly downregulated compared with the control and CCI groups on day 5 and returned to the normal level on day 12 following EA. After depleting NK cells by

  2. The MCRA model for probabilistic single-compound and cumulative risk assessment of pesticides. (United States)

    van der Voet, Hilko; de Boer, Waldo J; Kruisselbrink, Johannes W; Goedhart, Paul W; van der Heijden, Gerie W A M; Kennedy, Marc C; Boon, Polly E; van Klaveren, Jacob D


    Pesticide risk assessment is hampered by worst-case assumptions leading to overly pessimistic assessments. On the other hand, cumulative health effects of similar pesticides are often not taken into account. This paper describes models and a web-based software system developed in the European research project ACROPOLIS. The models are appropriate for both acute and chronic exposure assessments of single compounds and of multiple compounds in cumulative assessment groups. The software system MCRA (Monte Carlo Risk Assessment) is available for stakeholders in pesticide risk assessment at We describe the MCRA implementation of the methods as advised in the 2012 EFSA Guidance on probabilistic modelling, as well as more refined methods developed in the ACROPOLIS project. The emphasis is on cumulative assessments. Two approaches, sample-based and compound-based, are contrasted. It is shown that additional data on agricultural use of pesticides may give more realistic risk assessments. Examples are given of model and software validation of acute and chronic assessments, using both simulated data and comparisons against the previous release of MCRA and against the standard software DEEM-FCID used by the Environmental Protection Agency in the USA. It is shown that the EFSA Guidance pessimistic model may not always give an appropriate modelling of exposure. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

  3. An experimental study on cumulative prospect theory learning model of travelers’ dynamic mode choice under uncertainty

    Directory of Open Access Journals (Sweden)

    Chao Yang


    Full Text Available In this paper, we examined travelers’ dynamic mode choice behavior under travel time variability. We found travelers’ inconsistent risk attitudes through a binary mode choice experiment. Although the results deviated from the traditional utility maximization theory and could not be explained by the payoff variability effect, they could be well captured in a cumulative prospect theory (CPT framework. After considering the imperfect memory effect, we found that the prediction ability of the cumulative prospect theory learning (CPTL model could be significantly improved. The experimental results were also compared with the CPTL model and the reinforcement learning (REL model. This study empirically showed the potential of alternative theories to better capture travelers’ day-to-day mode choice behavior under uncertainty. A new definition of willingness to pay (WTP in a CPT framework was provided to explicitly consider travelers’ perceived value increases in travel time.

  4. Cumulative Psychosocial Risk, Parental Socialization, and Child Cognitive Functioning: A Longitudinal Cascade Model. (United States)

    Wade, Mark; Madigan, Sheri; Plamondon, Andre; Rodrigues, Michelle; Browne, Dillon; Jenkins, Jennifer M


    Previous studies have demonstrated that various psychosocial risks are associated with poor cognitive functioning in children, and these risks frequently cluster together. In the current longitudinal study, we tested a model in which it was hypothesized that cumulative psychosocial adversity of mothers would have deleterious effects on children's cognitive functioning by compromising socialization processes within families (i.e., parental competence). A prospective community birth cohort of 501 families was recruited when children were newborns. At this time, mothers reported on their current psychosocial circumstances (socioeconomic status, teen parenthood, depression, etc.), which were summed into a cumulative risk score. Families were followed up at 18 months and 3 years, at which point maternal reflective capacity and cognitive sensitivity were measured, respectively. Child cognition (executive functioning, theory of mind, and language ability) was assessed at age 4.5 using age-appropriate observational and standardized tasks. Analyses controlled for child age, gender, number of children in the home, number of years married, and mothers' history of adversity. The results revealed significant declines in child cognition as well as maternal reflective capacity and cognitive sensitivity as the number of psychosocial risks increased. Moreover, longitudinal path analysis showed significant indirect effects from cumulative risk to all three cognitive outcomes via reflective capacity and cognitive sensitivity. Findings suggest that cumulative risk of mothers may partially account for child cognitive difficulties in various domains by disrupting key parental socialization competencies. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  5. Random forests as cumulative effects models: A case study of lakes and rivers in Muskoka, Canada. (United States)

    Jones, F Chris; Plewes, Rachel; Murison, Lorna; MacDougall, Mark J; Sinclair, Sarah; Davies, Christie; Bailey, John L; Richardson, Murray; Gunn, John


    Cumulative effects assessment (CEA) - a type of environmental appraisal - lacks effective methods for modeling cumulative effects, evaluating indicators of ecosystem condition, and exploring the likely outcomes of development scenarios. Random forests are an extension of classification and regression trees, which model response variables by recursive partitioning. Random forests were used to model a series of candidate ecological indicators that described lakes and rivers from a case study watershed (The Muskoka River Watershed, Canada). Suitability of the candidate indicators for use in cumulative effects assessment and watershed monitoring was assessed according to how well they could be predicted from natural habitat features and how sensitive they were to human land-use. The best models explained 75% of the variation in a multivariate descriptor of lake benthic-macroinvertebrate community structure, and 76% of the variation in the conductivity of river water. Similar results were obtained by cross-validation. Several candidate indicators detected a simulated doubling of urban land-use in their catchments, and a few were able to detect a simulated doubling of agricultural land-use. The paper demonstrates that random forests can be used to describe the combined and singular effects of multiple stressors and natural environmental factors, and furthermore, that random forests can be used to evaluate the performance of monitoring indicators. The numerical methods presented are applicable to any ecosystem and indicator type, and therefore represent a step forward for CEA. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  6. Evidence of a cumulative effect for risk factors predicting low bone mass among male adolescent athletes. (United States)

    Barrack, Michelle T; Fredericson, Michael; Tenforde, Adam S; Nattiv, Aurelia


    Limited research has evaluated risk factors for low bone mineral density (BMD) in male adolescent athletes. To evaluate predictors of low BMD (defined as BMD Z-score athletes. Male adolescent athletes completed a survey characterising sports participation, nutrition, stress fracture history, dual energy X-ray absorptiometry (DXA)-measured BMD and body composition. Independent t-tests and analysis of covariance (ANCOVA) evaluated group differences; logistic regression evaluated low BMD risk factors. Runners (n=51) exhibited a lower body weight (p=0.02), body mass index (BMI) (kg/m 2 ) (p=0.02), per cent expected weight (p=0.02) and spine BMD Z-score (p=0.002) compared with non-runners (n=18). Single risk factors of low BMD included 30 in the past year (OR=6.4, 95% CI 1.5 to 27.1). The strongest two-variable and three-variable risk factors included weekly mileage >30+ stress fracture history (OR=17.3, 95% CI 1.6 to 185.6) and weekly mileage >30+stress fracture history (OR=17.3, 95% CI 1.6 to 185.6), respectively. Risk factors were cumulative when predicting low BMD (including 30, stress fracture history and <1 serving of calcium-rich food/day): 0-1 risk factors (11.1%), 2 risk factors (42.9%), or 3-4 risk factors (80.0%), p<0.001). Male adolescent runners exhibited lower body weight, BMI and spine BMD Z-score values. The risk of low BMD displayed a graded relationship with increasing risk factors, highlighting the importance of using methods to optimise bone mass in this population. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to

  7. A Simplified Infiltration Model for Predicting Cumulative Infiltration during Vertical Line Source Irrigation

    Directory of Open Access Journals (Sweden)

    Yanwei Fan


    Full Text Available Vertical line source irrigation is a water-saving irrigation method for enhancing direct water and nutrient delivery to the root zone, reducing soil evaporation and improving water and nutrient use efficiency. To identify its influencing factors, we performed computer simulations using the HYDRUS-2D software. The results indicate that for a given soil, the line source seepage area, but not the initial soil water content and buried depth, has a significant effect on the cumulative infiltration. We thus proposed a simplified method, taking into account the seepage area for predicting the cumulative infiltration based on the Philip model. Finally, we evaluated the accuracy of the simplified method using experimental data and found the cumulative infiltrations predicted by the simplified method were in very good agreement with the observed values, showing a low mean average error of 0.028–0.480 L, a root mean square error of 0.043–0.908 L, a percentage bias of 0.321–0.900 and a large Nash-Sutcliffe coefficient close to 1.0 (NSE ≥ 0.995. The results indicate that this simplified infiltration model, for which the only emitter parameter required is the seepage area, could provide a valuable and practical tool for irrigation design.

  8. An analytical model for cumulative infiltration into a dual-permeability media (United States)

    Peyrard, Xavier; Lassabatere, Laurent; Angulo-Jaramillo, Rafael; Simunek, Jiri


    Modeling of water infiltration into the vadose zone is important for better understanding of movement of water-transported contaminants. There is a great need to take into account the soil heterogeneity and, in particular, the presence of macropores or cracks that could generate preferential flow. Several mathematical models have been proposed to describe unsaturated flow through heterogeneous soils. The dual-permeability model assumes that flow is governed by Richards equation in both porous regions (matrix and fractures). Water can be exchanged between the two regions following a first-order rate law. A previous study showed that the influence of the hydraulic conductivity of the matrix/macropore interface had a little influence on cumulative infiltration at the soil surface. As a result, one could consider the surface infiltration for a specific case of no water exchange between the fracture and matrix regions (a case of zero interfacial hydraulic conductivity). In such a case, water infiltration can be considered to be the sum of the cumulative infiltrations into the matrix and the fractures. On the basis of analytical models for each sub domain (matrix and fractures), an analytical model is proposed for the entire dual-porosity system. A sensitivity analysis is performed to characterize the influence of several factors, such as the saturated hydraulic conductivity ratio, the water pressure scale parameter ratio, and the saturated volumetric water content scale ratio, on the total cumulative infiltration. Such an analysis greatly helps in quantifying the impact of macroporosity and fractures on water infiltration, which can be of great interest for hydrological models.

  9. Macroeconomic and Technological Dynamics: a Structuralist-Keynesian Cumulative Growth Model

    Directory of Open Access Journals (Sweden)

    Giulio Guarini


    Full Text Available In the Structuralist-Keynesian approach, economic growth is a cumulative causation process driven by a continuous interaction between macroeconomic and technological dynamics, involving several structural variables. In this context, labour productivity is both an input of the growth process, influencing macroeconomic dynamics, and a consequence of growth, because technological progress is endogenous and depends on macroeconomic dynamics. The aim of this paper is to build a Structuralist-Keynesian cumulative growth model driven by the dynamic interaction between the demand regime and the productivity regime. The model specifies the role of labour productivity and unit labour costs in the macroeconomic and technological dynamics. The results show that the effect of unit labour cost dynamics on economic growth depends on the degree of product market competition, innovation, and the distributional effects on aggregate demand. Finally, the main relationships of the model are empirically investigated for the European countries in the period 1992-2012, using both System GMM and Difference GMM dynamic panel models. JEL code: O41, O33, O47.

  10. Modeling Joint Exposures and Health Outcomes for Cumulative Risk Assessment: The Case of Radon and Smoking

    Directory of Open Access Journals (Sweden)

    Jonathan I. Levy


    Full Text Available Community-based cumulative risk assessment requires characterization of exposures to multiple chemical and non-chemical stressors, with consideration of how the non-chemical stressors may influence risks from chemical stressors. Residential radon provides an interesting case example, given its large attributable risk, effect modification due to smoking, and significant variability in radon concentrations and smoking patterns. In spite of this fact, no study to date has estimated geographic and sociodemographic patterns of both radon and smoking in a manner that would allow for inclusion of radon in community-based cumulative risk assessment. In this study, we apply multi-level regression models to explain variability in radon based on housing characteristics and geological variables, and construct a regression model predicting housing characteristics using U.S. Census data. Multi-level regression models of smoking based on predictors common to the housing model allow us to link the exposures. We estimate county-average lifetime lung cancer risks from radon ranging from 0.15 to 1.8 in 100, with high-risk clusters in areas and for subpopulations with high predicted radon and smoking rates. Our findings demonstrate the viability of screening-level assessment to characterize patterns of lung cancer risk from radon, with an approach that can be generalized to multiple chemical and non-chemical stressors.

  11. Third-order cumulants based method for continuous-time errors-in-variables system identification by fractional models

    International Nuclear Information System (INIS)

    Chetoui, Manel; Malti, Rachid; Thomassin, Magalie; Aoun, Mohamed; Najar, Slah; Abdelkrim, Naceur


    This paper deals with continuous-time system identification using fractional models in a noisy input/output context. The third-order cumulants based least squares method (tocls) is extended here to fractional models. The derivatives of the third-order cumulants are computed using a new fractional state variable filter. A numerical example is used to demonstrate the performance of the proposed method called ftocls (fractional third-order cumulants based least squares). The effect of the signal-to-noise ratio and the hyperparameter is studied.

  12. A Skill Score of Trajectory Model Evaluation Using Reinitialized Series of Normalized Cumulative Lagrangian Separation (United States)

    Liu, Y.; Weisberg, R. H.


    The Lagrangian separation distance between the endpoints of simulated and observed drifter trajectories is often used to assess the performance of numerical particle trajectory models. However, the separation distance fails to indicate relative model performance in weak and strong current regions, such as a continental shelf and its adjacent deep ocean. A skill score is proposed based on the cumulative Lagrangian separation distances normalized by the associated cumulative trajectory lengths. The new metrics correctly indicates the relative performance of the Global HYCOM in simulating the strong currents of the Gulf of Mexico Loop Current and the weaker currents of the West Florida Shelf in the eastern Gulf of Mexico. In contrast, the Lagrangian separation distance alone gives a misleading result. Also, the observed drifter position series can be used to reinitialize the trajectory model and evaluate its performance along the observed trajectory, not just at the drifter end position. The proposed dimensionless skill score is particularly useful when the number of drifter trajectories is limited and neither a conventional Eulerian-based velocity nor a Lagrangian-based probability density function may be estimated.

  13. Cumulative atomic multipole moments complement any atomic charge model to obtain more accurate electrostatic properties (United States)

    Sokalski, W. A.; Shibata, M.; Ornstein, R. L.; Rein, R.


    The quality of several atomic charge models based on different definitions has been analyzed using cumulative atomic multipole moments (CAMM). This formalism can generate higher atomic moments starting from any atomic charges, while preserving the corresponding molecular moments. The atomic charge contribution to the higher molecular moments, as well as to the electrostatic potentials, has been examined for CO and HCN molecules at several different levels of theory. The results clearly show that the electrostatic potential obtained from CAMM expansion is convergent up to R-5 term for all atomic charge models used. This illustrates that higher atomic moments can be used to supplement any atomic charge model to obtain more accurate description of electrostatic properties.

  14. [Assessment on the ecological suitability in Zhuhai City, Guangdong, China, based on minimum cumulative resistance model]. (United States)

    Li, Jian-fei; Li, Lin; Guo, Luo; Du, Shi-hong


    Urban landscape has the characteristics of spatial heterogeneity. Because the expansion process of urban constructive or ecological land has different resistance values, the land unit stimulates and promotes the expansion of ecological land with different intensity. To compare the effect of promoting and hindering functions in the same land unit, we firstly compared the minimum cumulative resistance value of promoting and hindering functions, and then looked for the balance of two landscape processes under the same standard. According to the ecology principle of minimum limit factor, taking the minimum cumulative resistance analysis method under two expansion processes as the evaluation method of urban land ecological suitability, this research took Zhuhai City as the study area to estimate urban ecological suitability by relative evaluation method with remote sensing image, field survey, and statistics data. With the support of ArcGIS, five types of indicators on landscape types, ecological value, soil erosion sensitivity, sensitivity of geological disasters, and ecological function were selected as input parameters in the minimum cumulative resistance model to compute urban ecological suitability. The results showed that the ecological suitability of the whole Zhuhai City was divided into five levels: constructive expansion prohibited zone (10.1%), constructive expansion restricted zone (32.9%), key construction zone (36.3%), priority development zone (2.3%), and basic cropland (18.4%). Ecological suitability of the central area of Zhuhai City was divided into four levels: constructive expansion prohibited zone (11.6%), constructive expansion restricted zone (25.6%), key construction zone (52.4%), priority development zone (10.4%). Finally, we put forward the sustainable development framework of Zhuhai City according to the research conclusion. On one hand, the government should strictly control the development of the urban center area. On the other hand, the

  15. An Evidence-Based Evaluation of the Cumulative Effects of Tidal Freshwater and Estuarine Ecosystem Restoration on Endangered Juvenile Salmon in the Columbia River: Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Diefenderfer, Heida L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Johnson, Gary E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Thom, Ronald M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Borde, Amy B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Woodley, Christa M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Weitkamp, Laurie A. [Marine Sciences lab., Sequim, WA (United States); Buenau, Kate E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kropp, Roy K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)


    The listing of 13 salmon and steelhead stocks in the Columbia River basin (hereafter collectively referred to as “salmon”) under the Endangered Species Act of 1973, as amended, has stimulated tidal wetland restoration in the lower 235 kilometers of the Columbia River and estuary for juvenile salmon habitat functions. The purpose of the research reported herein was to evaluate the effect on listed salmon of the restoration effort currently being conducted under the auspices of the federal Columbia Estuary Ecosystem Restoration Program (CEERP). Linking changes in the quality and landscape pattern of tidal wetlands in the lower Columbia River and estuary (LCRE) to salmon recovery is a complex problem because of the characteristics of the ecosystem, the salmon, the restoration actions, and available sampling technologies. Therefore, we designed an evidence-based approach to develop, synthesize, and evaluate information to determine early-stage (~10 years) outcomes of the CEERP. We developed an ecosystem conceptual model and from that, a primary hypothesis that habitat restoration activities in the LCRE have a cumulative beneficial effect on juvenile salmon. There are two necessary conditions of the hypothesis: • habitat-based indicators of ecosystem controlling factors, processes, and structures show positive effects from restoration actions, and • fish-based indicators of ecosystem processes and functions show positive effects from restoration actions and habitats undergoing restoration. Our evidence-based approach to evaluate the primary hypothesis incorporated seven lines of evidence, most of which are drawn from the LCRE. The lines of evidence are spatial and temporal synergies, cumulative net ecosystem improvement, estuary-wide meta-analysis, offsite benefits to juvenile salmon, landscape condition evaluation, and evidence-based scoring of global literature. The general methods we used to develop information for the lines of evidence included field

  16. Cumulative Training Dose's Effects on Interrelationships Between Common Training-Load Models During Basketball Activity. (United States)

    Scanlan, Aaron T; Fox, Jordan L; Borges, Nattai R; Dascombe, Ben J; Dalbo, Vincent J


    The influence of various factors on training-load (TL) responses in basketball has received limited attention. This study aimed to examine the temporal changes and influence of cumulative training dose on TL responses and interrelationships during basketball activity. Ten state-level Australian male junior basketball players completed 4 × 10-min standardized bouts of simulated basketball activity using a circuit-based protocol. Internal TL was quantified using the session rating of perceived exertion (sRPE), summated heart-rate zones (SHRZ), Banister training impulse (TRIMP), and Lucia TRIMP models. External TL was assessed via measurement of mean sprint and circuit speeds. Temporal TL comparisons were performed between 10-min bouts, while Pearson correlation analyses were conducted across cumulative training doses (0-10, 0-20, 0-30, and 0-40 min). sRPE TL increased (P basketball activity. sRPE TL was only significantly related to Lucia TRIMP (r = .66-.69; P training doses (r = .84-.89; P basketball training doses lasting beyond 20 min. Thus, the interchangeability of commonly used internal and external TL approaches appears dose-dependent during basketball activity, with various psychophysiological mediators likely underpinning temporal changes.

  17. From cumulative cultural transmission to evidence-based medicine: Evolution of medicinal plant knowledge in Southern Italy

    Directory of Open Access Journals (Sweden)

    Marco eLeonti


    Full Text Available In Mediterranean cultures written records of medicinal plant use have a long tradition. This written record contributed to building a consensus about what was perceived to be an efficacious pharmacopoeia. Passed down through millennia, these scripts have transmitted knowledge about plant uses, with high fidelity, to scholars and laypersons alike. Herbal medicine’s importance and the long-standing written record call for a better understanding of the mechanisms influencing the transmission of contemporary medicinal plant knowledge. Here we contextualize herbal medicine within evolutionary medicine and cultural evolution. Cumulative knowledge transmission is approached by estimating the causal effect of two seminal scripts about materia medica written by Dioscorides and Galen, two classical Greco-Roman physicians, on today’s medicinal plant use in the Southern Italian regions of Campania, Sardinia and Sicily. Plant-use combinations are treated as transmissible cultural traits (or memes, which in analogy to the biological evolution of genetic traits, are subjected to mutation and selection. Our results suggest that until today ancient scripts have exerted a strong influence on the use of herbal medicine. We conclude that the repeated empirical testing and scientific study of health care claims is guiding and shaping the selection of efficacious treatments and evidence-based herbal medicine.

  18. Expert opinion on laparoscopic surgery for colorectal cancer parallels evidence from a cumulative meta-analysis of randomized controlled trials.

    Directory of Open Access Journals (Sweden)

    Guillaume Martel

    Full Text Available This study sought to synthesize survival outcomes from trials of laparoscopic and open colorectal cancer surgery, and to determine whether expert acceptance of this technology in the literature has parallel cumulative survival evidence.A systematic review of randomized trials was conducted. The primary outcome was survival, and meta-analysis of time-to-event data was conducted. Expert opinion in the literature (published reviews, guidelines, and textbook chapters on the acceptability of laparoscopic colorectal cancer was graded using a 7-point scale. Pooled survival data were correlated in time with accumulating expert opinion scores.A total of 5,800 citations were screened. Of these, 39 publications pertaining to 23 individual trials were retained. As well, 414 reviews were included (28 guidelines, 30 textbook chapters, 20 systematic reviews, 336 narrative reviews. In total, 5,782 patients were randomized to laparoscopic (n = 3,031 and open (n = 2,751 colorectal surgery. Survival data were presented in 16 publications. Laparoscopic surgery was not inferior to open surgery in terms of overall survival (HR = 0.94, 95% CI 0.80, 1.09. Expert opinion in the literature pertaining to the oncologic acceptability of laparoscopic surgery for colon cancer correlated most closely with the publication of large RCTs in 2002-2004. Although increasingly accepted since 2006, laparoscopic surgery for rectal cancer remained controversial.Laparoscopic surgery for colon cancer is non-inferior to open surgery in terms of overall survival, and has been so since 2004. The majority expert opinion in the literature has considered these two techniques to be equivalent since 2002-2004. Laparoscopic surgery for rectal cancer has been increasingly accepted since 2006, but remains controversial. Knowledge translation efforts in this field appear to have paralleled the accumulation of clinical trial evidence.

  19. Optimal policies for cumulative damage models with maintenance last and first

    International Nuclear Information System (INIS)

    Zhao, Xufeng; Qian, Cunhua; Nakagawa, Toshio


    From the economical viewpoint of several combined PM policies in reliability theory, this paper takes up a standard cumulative damage model in which the notion of maintenance last is applied, i.e., the unit undergoes preventive maintenances before failure at a planned time T, at a damage level Z, or at a shock number N, whichever occurs last. Expected cost rates are detailedly formulated, and optimal problems of two alternative policies which combine time-based with condition-based preventive maintenances are discussed, i.e., optimal T L ⁎ for N, Z L ⁎ for T, and N L ⁎ for T are rigorously obtained. Comparison methods between such maintenance last and conventional maintenance first are explored. It is determined theoretically and numerically which policy should be adopted, according to the different methods in different cases when the time-based or the condition-based PM policy is optimized.

  20. Flexible parametric modelling of the cause-specific cumulative incidence function. (United States)

    Lambert, Paul C; Wilkes, Sally R; Crowther, Michael J


    Competing risks arise with time-to-event data when individuals are at risk of more than one type of event and the occurrence of one event precludes the occurrence of all other events. A useful measure with competing risks is the cause-specific cumulative incidence function (CIF), which gives the probability of experiencing a particular event as a function of follow-up time, accounting for the fact that some individuals may have a competing event. When modelling the cause-specific CIF, the most common model is a semi-parametric proportional subhazards model. In this paper, we propose the use of flexible parametric survival models to directly model the cause-specific CIF where the effect of follow-up time is modelled using restricted cubic splines. The models provide smooth estimates of the cause-specific CIF with the important advantage that the approach is easily extended to model time-dependent effects. The models can be fitted using standard survival analysis tools by a combination of data expansion and introducing time-dependent weights. Various link functions are available that allow modelling on different scales and have proportional subhazards, proportional odds and relative absolute risks as particular cases. We conduct a simulation study to evaluate how well the spline functions approximate subhazard functions with complex shapes. The methods are illustrated using data from the European Blood and Marrow Transplantation Registry showing excellent agreement between parametric estimates of the cause-specific CIF and those obtained from a semi-parametric model. We also fit models relaxing the proportional subhazards assumption using alternative link functions and/or including time-dependent effects. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  1. Using cumulative sums of martingale residuals for model checking in nested case-control studies. (United States)

    Borgan, Ørnulf; Zhang, Ying


    Standard use of Cox regression requires collection of covariate information for all individuals in a cohort even when only a small fraction of them experiences the event of interest (fail). This may be very expensive for large cohorts. Further in biomarker studies, it will imply a waste of valuable biological material that one may want to save for future studies. A nested case-control study offers a useful alternative. For this design, covariate information is only needed for the failing individuals (cases) and a sample of controls selected from the cases' at-risk sets. Methods based on martingale residuals are useful for checking the fit of Cox's regression model for cohort data. But similar methods have so far not been developed for nested case-control data. In this article, it is described how one may define martingale residuals for nested case-control data, and it is shown how plots and tests based on cumulative sums of martingale residuals may be used to check model fit. The plots and tests may be obtained using available software. © 2015, The International Biometric Society.

  2. Study of cumulative fatigue damage detection for used parts with nonlinear output frequency response functions based on NARMAX modelling (United States)

    Huang, Honglan; Mao, Hanying; Mao, Hanling; Zheng, Weixue; Huang, Zhenfeng; Li, Xinxin; Wang, Xianghong


    Cumulative fatigue damage detection for used parts plays a key role in the process of remanufacturing engineering and is related to the service safety of the remanufactured parts. In light of the nonlinear properties of used parts caused by cumulative fatigue damage, the based nonlinear output frequency response functions detection approach offers a breakthrough to solve this key problem. First, a modified PSO-adaptive lasso algorithm is introduced to improve the accuracy of the NARMAX model under impulse hammer excitation, and then, an effective new algorithm is derived to estimate the nonlinear output frequency response functions under rectangular pulse excitation, and a based nonlinear output frequency response functions index is introduced to detect the cumulative fatigue damage in used parts. Then, a novel damage detection approach that integrates the NARMAX model and the rectangular pulse is proposed for nonlinear output frequency response functions identification and cumulative fatigue damage detection of used parts. Finally, experimental studies of fatigued plate specimens and used connecting rod parts are conducted to verify the validity of the novel approach. The obtained results reveal that the new approach can detect cumulative fatigue damages of used parts effectively and efficiently and that the various values of the based nonlinear output frequency response functions index can be used to detect the different fatigue damages or working time. Since the proposed new approach can extract nonlinear properties of systems by only a single excitation of the inspected system, it shows great promise for use in remanufacturing engineering applications.

  3. Modeling Joint Exposures and Health Outcomes for Cumulative Risk Assessment: the Case of Radon and Smoking (United States)

    Community-based cumulative risk assessment requires characterization of exposures to multiple chemical and non-chemical stressors, with consideration of how the non-chemical stressors may influence risks from chemical stressors. Residential radon provides an interesting case exam...

  4. A Longitudinal Study of Reading Comprehension Achievement from Grades 3 to 10: Investigating Models of Stability, Cumulative Growth, and Compensation (United States)

    Kwiatkowska-White, Bozena; Kirby, John R.; Lee, Elizabeth A.


    This longitudinal study of 78 Canadian English-speaking students examined the applicability of the stability, cumulative, and compensatory models in reading comprehension development. Archival government-mandated assessments of reading comprehension at Grades 3, 6, and 10, and the Canadian Test of Basic Skills measure of reading comprehension…

  5. Testing of a cumulative and aggregate exposure model using biomonitoring studies and dietary records for Italian vineyard spray operators.

    NARCIS (Netherlands)

    Kennedy, M.C.; Glass, C.R.; Fustinoni, S.; Moretto, A.; Mandic-Rajcevic, S.; Riso, P.; Turrini, A.; Voet, van der H.; Hetmanski, M.T.; Fussel, R.J.; Klaveren, van J.D.


    The need for improved tools to estimate the cumulative and aggregate exposure to compounds such as plant protection products (PPPs) is recognised in the EU Regulation 1107/2009. A new model has been developed to estimate the exposure within a population to single compounds or compounds within a

  6. Effective interventions for cumulative trauma disorders of the upper extremity in computer users: practice models based on systematic review. (United States)

    Goodman, Glenn; Kovach, Laura; Fisher, April; Elsesser, Elizabeth; Bobinski, Daniel; Hansen, Jessica


    A systematic review of over 4600 abstracts was performed to address the effectiveness of the current cumulative trauma disorder (CTD) interventions focused on the upper extremities of computer users. The researchers were the study participants. They included one Professor of Occupational Therapy and five Masters of Occupational Therapy Students from a Midwestern University. The Professor of Occupational Therapy has been practicing for 29 years. The researchers employed stringent inclusion criteria for this review based on similar systematic review papers. Criteria for high quality qualitative research were incorporated to include studies other than randomized-controlled trials. This approach considered knowledge gained from specific interventions that were studied in greater detail with fewer clients. The results of this study identified 25 articles that met the inclusion criteria. Further review ranked the selected articles into high, medium, or low quality based on criteria adapted from other studies. The highest levels of evidence were found for education and training in ergonomics, forearm supports, ergonomic keyboards, ergonomic mice, and exercise/rest breaks. Two models of practice were created from this review to assist occupational therapists or other professionals with intervention strategies for computer users with CTDs.

  7. Quantification of the cumulative effects of river training works on the basin scale with 2D flood modelling (United States)

    Zischg, Andreas Paul; Felder, Guido; WWeingartner, Rolf


    The catchment of the river Aare upstream of Bern, Switzerland, with an area of approx. 3000 km2 is a complex network of sub-catchments with different runoff characteristics; it also includes two larger lakes. Most of the rivers were regulated in the 18th century. An important regulation, however, was realised as early as in the 17th century. For this catchment, the worst case flood event was identified and its consequences were analysed. Beside the hydro-meteorological characteristics, an important basis to model the worst case flood is to understand the non-linear effects of flood retention in the valley bottom and in the lakes. The aim of this study was to compare these effects based on both the current river network and the historic one prior to the main river training works. This allows to quantify the human impacts. Methodologically, we set up a coupled 2D flood model representing the floodplains of the river Aare as well as of the tributaries Lombach, Lütschine, Zulg, Rotache, Chise and Guerbe. The flood simulation was made in 2D with the software BASEMENT-ETH (Vetsch et al. 2014). The model was calibrated by means of reproducing the large floods in August 2005 and the bankfull discharge for all river reaches. The model computes the discharge at the outlet of the Aare catchment at Bern by routing all discharges from the sub-catchments through the river reaches and their floodplains. With this, the modulation of the input hydrographs by widespread floodings in the floodplains can be quantified. The same configuration was applied on the basis of reconstructed digital terrain models representing the landscape and the river network before the first significant river training works had been realised. This terrain model was reconstructed by georeferencing and digitalizing historic maps and cross-sections combined with the mapping of the geomorphologic evidences of former river structures in non-modified areas. The latter mapping procedure was facilitated by the

  8. Assessment of cumulative evidence for the association between glutathione S-transferase polymorphisms and lung cancer: application of the Venice interim guidelines. (United States)

    Langevin, Scott M; Ioannidis, John P A; Vineis, Paolo; Taioli, Emanuela


    There is an overwhelming abundance of genetic association studies available in the literature, which can often be collectively difficult to interpret. To address this issue, the Venice interim guidelines were established for determining the credibility of the cumulative evidence. The objective of this report is to evaluate the literature on the association of common glutathione S-transferase (GST) variants (GSTM1 null, GSTT1 null and GSTP1 Ile105Val polymorphism) and lung cancer, and to assess the credibility of the associations using the newly proposed cumulative evidence guidelines. Information from the literature was enriched with an updated meta-analysis and a pooled analysis using data from the Genetic Susceptibility to Environmental Carcinogens database. There was a significant association between GSTM1 null and lung cancer for the meta-analysis (meta odds ratio=1.17, 95% confidence interval: 1.10-1.25) and pooled analysis (adjusted odds ratio=1.10, 95% confidence interval: 1.04-1.16), although substantial heterogeneity was present. No overall association between lung cancer and GSTT1 null or GSTP1 Ile105Val was found. When the Venice criteria was applied, cumulative evidence for all associations were considered 'weak', with the exception of East Asian carriers of the G allele of GSTP1 Ile105Val, which was graded as 'moderate' evidence. Despite the large amounts of studies, and several statistically significant summary estimates produced by meta-analyses, the application of the Venice criteria suggests extensive heterogeneity and susceptibility to bias for the studies on association of common genetic polymorphisms, such as with GST variants and lung cancer.

  9. Industrial and ecological cumulative exergy consumption of the United States via the 1997 input-output benchmark model

    International Nuclear Information System (INIS)

    Ukidwe, Nandan U.; Bakshi, Bhavik R.


    This paper develops a thermodynamic input-output (TIO) model of the 1997 United States economy that accounts for the flow of cumulative exergy in the 488-sector benchmark economic input-output model in two different ways. Industrial cumulative exergy consumption (ICEC) captures the exergy of all natural resources consumed directly and indirectly by each economic sector, while ecological cumulative exergy consumption (ECEC) also accounts for the exergy consumed in ecological systems for producing each natural resource. Information about exergy consumed in nature is obtained from the thermodynamics of biogeochemical cycles. As used in this work, ECEC is analogous to the concept of emergy, but does not rely on any of its controversial claims. The TIO model can also account for emissions from each sector and their impact and the role of labor. The use of consistent exergetic units permits the combination of various streams to define aggregate metrics that may provide insight into aspects related to the impact of economic sectors on the environment. Accounting for the contribution of natural capital by ECEC has been claimed to permit better representation of the quality of ecosystem goods and services than ICEC. The results of this work are expected to permit evaluation of these claims. If validated, this work is expected to lay the foundation for thermodynamic life cycle assessment, particularly of emerging technologies and with limited information

  10. Surfactant-induced skin irritation and skin repair: evaluation of a cumulative human irritation model by noninvasive techniques. (United States)

    Wilhelm, K P; Freitag, G; Wolff, H H


    Although surfactant-induced acute irritant dermatitis has been extensively studied, our understanding about the induction and repair of the clinically more relevant chronic form is limited. Our purpose was to investigate qualitative and quantitative differences in surfactant-induced irritant skin reactions from cumulative exposure to structurally unrelated surfactants and to compare the maximal irritant responses from this model with corresponding reactions noted in a previously reported acute irritation model. Sodium lauryl sulfate (SLS), dodecyl trimethyl ammonium bromide (DTAB), and potassium soap were the model irritants. Surfactant solutions (7.5%) were applied for 20 minutes daily (for 8 consecutive days excluding the weekend) to the volar aspect of the forearm of 11 volunteers. Irritant reactions were repeatedly assessed until complete healing was indicated by visual assessment and by measurements of transepidermal water loss (TEWL), erythema (skin color reflectance), and stratum corneum hydration (electrical capacitance). Maximum irritant responses were compared with corresponding reactions from an acute irritation model. TEWL was increased by SLS and DTAB to the same extent, but erythema was significantly higher in DTAB-treated skin. Skin dryness, as demonstrated by decreased capacitance values and increased scores for scaling and fissuring, was significantly more pronounced than in an acute irritation model for SLS and DTAB, although no difference was detected between the two surfactants. Potassium soap led to a slight increase in TEWL, whereas the remaining features were not significantly changed. This chronic irritation model appears to represent the clinical situation of irritant contact dermatitis with pronounced skin dryness more closely than the acute irritation model. The present study confirms that an extended time is needed for complete healing of irritant skin reactions. We also demonstrated that the evaluation of the irritation potential of

  11. Cumulative dietary exposure to a selected group of pesticides of the triazole group in different European countries according to the EFSA guidance on probabilistic modelling

    DEFF Research Database (Denmark)

    Boon, Polly E.; van Donkersgoed, Gerda; Christodoulou, Despo


    The practicality was examined of performing a cumulative dietary exposure assessment according to the requirements of the EFSA guidance on probabilistic modelling. For this the acute and chronic cumulative exposure to triazole pesticides was estimated using national food consumption and monitoring...

  12. Weighted cumulative exposure models helped identify an association between early knee-pain consultations and future knee OA diagnosis. (United States)

    Yu, Dahai; Peat, George; Bedson, John; Edwards, John J; Turkiewicz, Aleksandra; Jordan, Kelvin P


    To establish the association between prior knee-pain consultations and early diagnosis of knee osteoarthritis (OA) by weighted cumulative exposure (WCE) models. Data were from an electronic health care record (EHR) database (Consultations in Primary Care Archive). WCE functions for modeling the cumulative effect of time-varying knee-pain consultations weighted by recency were derived as a predictive tool in a population-based case-control sample and validated in a prospective cohort sample. Two WCE functions ([i] weighting of the importance of past consultations determined a priori; [ii] flexible spline-based estimation) were comprehensively compared with two simpler models ([iii] time since most recent consultation; total number of past consultations) on model goodness of fit, discrimination, and calibration both in derivation and validation phases. People with the most recent and most frequent knee-pain consultations were more likely to have high WCE scores that were associated with increased risk of knee OA diagnosis both in derivation and validation phases. Better model goodness of fit, discrimination, and calibration were observed for flexible spline-based WCE models. WCE functions can be used to model prediagnostic symptoms within routine EHR data and provide novel low-cost predictive tools contributing to early diagnosis. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  13. Burden of cumulative risk factors associated with non-communicable diseases among adults in Uganda: evidence from a national baseline survey. (United States)

    Wesonga, Ronald; Guwatudde, David; Bahendeka, Silver K; Mutungi, Gerald; Nabugoomu, Fabian; Muwonge, James


    Modification of known risk factors has been the most tested strategy for dealing with non-communicable diseases (NCDs). The cumulative number of NCD risk factors exhibited by an individual depicts a disease burden. However, understanding the risk factors associated with increased NCD burden has been constrained by scarcity of nationally representative data, especially in the developing countries and not well explored in the developed countries as well. Assessment of key risk factors for NCDs using population data drawn from 3987 participants in a nationally representative baseline survey in Uganda was made. Five key risk factors considered for the indicator variable included: high frequency of tobacco smoking, less than five servings of fruit and vegetables per day, low physical activity levels, high body mass index and raised blood pressure. We developed a composite indicator dependent variable with counts of number of risk factors associated with NCDs per participant. A statistical modeling framework was developed and a multinomial logistic regression model was fitted. The endogenous and exogenous predictors of NCD cumulative risk factors were assessed. A novel model framework for cumulative number of NCD risk factors was developed. Most respondents, 38 · 6% exhibited one or two NCD risk factors each. Of the total sample, 56 · 4% had at least two risk factors whereas only 5.3% showed no risk factor at all. Body mass index, systolic blood pressure, diastolic blood pressure, consumption of fruit and vegetables, age, region, residence, type of residence and land tenure system were statistically significant predictors of number of NCD risk factors (p non-communicable disease burden is on the increase, with more participants reporting to have at least two risk factors. Our findings imply that, besides endogenous factors, exogenous factors such as region, residence status, land tenure system and behavioral characteristics have significant causal effects on

  14. A cumulative risk factor model for early identification of academic difficulties in premature and low birth weight infants. (United States)

    Roberts, G; Bellinger, D; McCormick, M C


    Premature and low birth weight children have a high prevalence of academic difficulties. This study examines a model comprised of cumulative risk factors that allows early identification of these difficulties. This is a secondary analysis of data from a large cohort of premature (mathematics. Potential predictor variables were categorized into 4 domains: sociodemographic, neonatal, maternal mental health and early childhood (ages 3 and 5). Regression analysis was used to create a model to predict reading and mathematics scores. Variables from all domains were significant in the model, predicting low achievement scores in reading (R (2) of 0.49, model p-value mathematics (R (2) of 0.44, model p-value education and income, and Black or Hispanic race (sociodemographic); lower birth weight and male gender (neonatal); lower maternal responsivity (maternal mental health); lower intelligence, visual-motor skill and higher behavioral disturbance scores (early childhood). Lower mathematics scores were predicted by lower maternal education, income and age and Black or Hispanic race (sociodemographic); lower birth weight and higher head circumference (neonatal); lower maternal responsivity (maternal mental health); lower intelligence, visual-motor skill and higher behavioral disturbance scores (early childhood). Sequential early childhood risk factors in premature and LBW children lead to a cumulative risk for academic difficulties and can be used for early identification.

  15. Physics-Based Stress Corrosion Cracking Component Reliability Model cast in an R7-Compatible Cumulative Damage Framework

    International Nuclear Information System (INIS)

    Unwin, Stephen D.; Lowry, Peter P.; Layton, Robert F.; Toloczko, Mychailo B.; Johnson, Kenneth I.; Sanborn, Scott E.


    This is a working report drafted under the Risk-Informed Safety Margin Characterization pathway of the Light Water Reactor Sustainability Program, describing statistical models of passives component reliabilities. The Risk-Informed Safety Margin Characterization (RISMC) pathway is a set of activities defined under the U.S. Department of Energy Light Water Reactor Sustainability Program. The overarching objective of RISMC is to support plant life-extension decision-making by providing a state-of-knowledge characterization of safety margins in key systems, structures, and components (SSCs). The methodology emerging from the RISMC pathway is not a conventional probabilistic risk assessment (PRA)-based one; rather, it relies on a reactor systems simulation framework in which physical conditions of normal reactor operations, as well as accident environments, are explicitly modeled subject to uncertainty characterization. RELAP 7 (R7) is the platform being developed at Idaho National Laboratory to model these physical conditions. Adverse effects of aging systems could be particularly significant in those SSCs for which management options are limited; that is, components for which replacement, refurbishment, or other means of rejuvenation are least practical. These include various passive SSCs, such as piping components. Pacific Northwest National Laboratory is developing passive component reliability models intended to be compatible with the R7 framework. In the R7 paradigm, component reliability must be characterized in the context of the physical environments that R7 predicts. So, while conventional reliability models are parametric, relying on the statistical analysis of service data, RISMC reliability models must be physics-based and driven by the physical boundary conditions that R7 provides, thus allowing full integration of passives into the R7 multi-physics environment. The model must also be cast in a form compatible with the cumulative damage framework that R7

  16. Lack of association between MTHFR A1298C variant and Alzheimer's disease: evidence from a systematic review and cumulative meta-analysis. (United States)

    Liu, Shumin; Wu, Yongfu; Liu, Xu; Zhou, Jiahui; Wang, Ziyou; He, Zhiwei; Huang, Zunnan


    Previous studies have investigated the association between MTHFR A1298C (rs1801131) polymorphism and susceptibility to Alzheimer's disease (AD). Nevertheless, an ultimate conclusion remains obscure. We then executed this meta-analysis to estimate this association more precisely. Related studies were systematically searched on PubMed, Embase, China National Knowledge Infrastructure, Google scholar, and AlzGene databases. The association was evaluated by reviewing the odds ratios (ORs) with corresponding 95% confidence intervals (CIs). Publication bias, sensitivity analysis, and cumulative meta-analysis were performed to help draw a more definite conclusion. Ten eligible studies were finally enrolled in this meta-analysis. Lack of association between MTHFR A1298C polymorphism and AD risk was observed in five genetic models (allelic: OR = 1.17, 95% CI: 0.88-1.56; homozygous: OR = 1.15, 95% CI: 0.87-1.53; heterozygous: OR = 1.19, 95% CI: 0.76-1.86; dominant: OR = 1.23, 95% CI: 0.81-1.87; recessive: OR = 1.16, 95% CI: 0.89-1.52). The result of cumulative meta-analysis sorted by publication year was also detected a dynamic tendency of no correlation between MTHFR A1298C polymorphism and AD. This meta-analysis reveals that MTHFR A1298C polymorphism may not be associated with AD risk.

  17. Diclofenac sodium 3% gel for the management of actinic keratosis: 10+ years of cumulative evidence of efficacy and safety. (United States)

    Martin, George M; Stockfleth, Eggert


    Diclofenac sodium 3% gel (Solaraze®) gained US approval for the treatment of actinic keratosis (AK) more than 10 years ago. Since the publication of the pivotal phase 3 studies, numerous clinical studies have assessed use of this therapy in a variety of body areas, special populations, and novel combinations. To provide a comprehensive update on clinical data and research on the use of diclofenac sodium 3% gel in AK. Review of the literature. Accumulating evidence from preclinical research supports that the proposed mechanism of diclofenac sodium 3% gel may include cyclo-oxgenase 2 (COX-2) inhibition, inhibition of angiogenesis, and induction of apoptosis. A literature review identified 17 publications (beyond the 2 pivotal studies) on the use of diclofenac sodium 3% gel for AK. A phase 4 open-label study reported that 58 percent of patients achieved complete clearance of target lesions at the 30-day post-treatment assessment; among patients who were evaluable at 1-year post-treatment, sustained long-term clearance of AK lesions was observed. Active comparator studies demonstrated comparable efficacy of diclofenac sodium 3% gel with 5-fluorouracil 5% and imiquimod 5%. Publications on the efficacy of diclofenac sodium 3% gel for AK of the lip report complete clearance rates comparable to those reported for other body areas. Diclofenac sodium 3% gel has also demonstrated efficacy for clearing AK lesions in immunosuppressed populations. Sequential use of diclofenac sodium 3% gel with cryosurgery or photodynamic therapy has been investigated and may emerge as a useful approach for some patients. Diclofenac sodium 3% gel has a unique proposed mechanism of action in AK that may involve COX-2 inhibition, inhibition of angiogenesis, and induction of apoptosis. In the past decade, numerous clinical studies have demonstrated this topical therapy to be effective and well tolerated for the treatment of AK.

  18. Checking Fine and Gray subdistribution hazards model with cumulative sums of residuals

    DEFF Research Database (Denmark)

    Li, Jianing; Scheike, Thomas; Zhang, Mei Jie


    Recently, Fine and Gray (J Am Stat Assoc 94:496–509, 1999) proposed a semi-parametric proportional regression model for the subdistribution hazard function which has been used extensively for analyzing competing risks data. However, failure of model adequacy could lead to severe bias in parameter...

  19. Cumulative and Averaging Fission of Beliefs


    Josang, Audun


    Belief fusion is the principle of combining separate beliefs or bodies of evidence originating from different sources. Depending on the situation to be modelled, different belief fusion methods can be applied. Cumulative and averaging belief fusion is defined for fusing opinions in subjective logic, and for fusing belief functions in general. The principle of fission is the opposite of fusion, namely to eliminate the contribution of a specific belief from an already fused belief, with the pur...

  20. Regional Cumulative Effects Groundwater Management Associated with Large Resource Development Projects: Integrating Adaptive Management with Monitoring and Modelling (United States)

    Beckers, J.; Fennell, J.; Scott, M.


    We will present a systematic approach to cumulative effects groundwater management predicated on an integration of traditional tools and the necessary intimate connection between modelling, monitoring and adaptive management, which includes an inventory and gap analysis of available data, consideration for system dynamics in the context of climate variability and change, an assessment of aquifer vulnerability, and consideration for potential future development and overall associated risk to groundwater resources and connected receptors. In our experience, a systematic approach to cumulative effects groundwater management is key to addressing complex challenges associated with large resource development projects, with effects of these projects to aquifer systems often occurring at regional scales and possibly enduring over long time horizons. The principal goal for the groundwater management framework is to manage groundwater resources in a sustainable manner and protect it from over-use. However, proper balances with economic and community objectives need to be taken into account, emphasizing the need for stakeholder engagement in the overall process. Through an understanding of inter-relationships between natural resource and other objectives, legislation, policies and programs across various sectors goals can be developed to achieve the best overall long-term benefits for society and the environment, while minimizing conflicts. The principal goal of monitoring is to evaluate past and current conditions and address data gaps. Long-term monitoring can also be used to improve the hydrogeologic conceptualization of a region. The role of numerical modelling is to quantify the understanding of groundwater flow systems in a region, address uncertainty in this understanding, to quantify potential regional cumulative impacts of current and future development, to provide recommendations for future monitoring locations and targets and for assessing the effectiveness of

  1. An aggregate method to calibrate the reference point of cumulative prospect theory-based route choice model for urban transit network (United States)

    Zhang, Yufeng; Long, Man; Luo, Sida; Bao, Yu; Shen, Hanxia


    Transit route choice model is the key technology of public transit systems planning and management. Traditional route choice models are mostly based on expected utility theory which has an evident shortcoming that it cannot accurately portray travelers' subjective route choice behavior for their risk preferences are not taken into consideration. Cumulative prospect theory (CPT), a brand new theory, can be used to describe travelers' decision-making process under the condition of uncertainty of transit supply and risk preferences of multi-type travelers. The method to calibrate the reference point, a key parameter to CPT-based transit route choice model, determines the precision of the model to a great extent. In this paper, a new method is put forward to obtain the value of reference point which combines theoretical calculation and field investigation results. Comparing the proposed method with traditional method, it shows that the new method can promote the quality of CPT-based model by improving the accuracy in simulating travelers' route choice behaviors based on transit trip investigation from Nanjing City, China. The proposed method is of great significance to logical transit planning and management, and to some extent makes up the defect that obtaining the reference point is solely based on qualitative analysis.

  2. Is the cluster risk model of parental adversities better than the cumulative risk model as an indicator of childhood physical abuse?: findings from two representative community surveys. (United States)

    Fuller-Thomson, E; Sawyer, J-L


    Screening strategies for childhood physical abuse (CPA) need to be improved in order to identify those most at risk. This study uses two regionally representative community samples to examine whether a cluster or cumulative model of risk indicators (i.e. parental divorce, parental unemployment, and parental addictions) explains a larger proportion of the variation in CPA. Data were drawn from Statistics Canada's National Population Health Survey (1994-1995) and Canadian Community Health Survey 3.1 (2005). Response rates were greater than 80% in both samples. Each survey had approximately 13,000 respondents aged 18 and over who answered questions about the above adverse childhood experiences. A gradient was shown with similar outcomes in each data set. Only 3.4% of adults who experienced none of the three risk indicators reported they had been physically abused during childhood or adolescence. The prevalence of CPA was greater among those who experienced parental divorce alone (8.3%-10.7%), parental unemployment alone (8.9%-9.7%) or parental addictions alone (18.0%-19.5%). When all three risk indicators were present, the prevalence of CPA ranged from 36.0%-41.0% and the age-sex-race adjusted odds were greater than 15 times that of individuals with none of the three risk indicators. The cluster model explained a statistically significantly larger proportion of the variation than the cumulative model although the difference between the two models was modest. For the purposes of parsimony, the cumulative model may be the better alternative. Adults who were exposed to two or more childhood risk indicators were much more likely to report that they were physically abused during their childhood than those with only one or no risk factors. Medical professionals may use this information on cumulative risk factors to more effectively target screening for potential CPA. Future research should include prospective studies. © 2012 John Wiley & Sons Ltd.

  3. Predicting Cumulative Incidence Probability by Direct Binomial Regression

    DEFF Research Database (Denmark)

    Scheike, Thomas H.; Zhang, Mei-Jie

    Binomial modelling; cumulative incidence probability; cause-specific hazards; subdistribution hazard......Binomial modelling; cumulative incidence probability; cause-specific hazards; subdistribution hazard...

  4. Marginal structural model to evaluate the association between cumulative osteoporosis medication and infection using claims data. (United States)

    Xue, F; Goli, V; Petraro, P; McMullan, T; Sprafka, J M; Tchetgen Tchetgen, E J


    Due to the suboptimal persistence to osteoporosis (OP) treatment, factors triggering treatment discontinuation/switching may be causing time-varying confounding. BP treatment was associated with the risk of overall infection in opposite directions in the unweighted Cox model versus the weighted MSM. The discrepancy of effect estimates for overall infection in the MSM suggested there may be time-varying confounding. Due to the suboptimal persistence to osteoporosis (OP) treatment, factors triggering treatment discontinuation/switching may be affected by prior treatment and confound the subsequent treatment effect, causing time-varying confounding. In a US insurance database, the association between joint treatment of bisphosphonates (BP) and other OP medication and the incidence of infections among postmenopausal women was assessed using a marginal structural model (MSM). Stabilized weights were estimated by modeling treatment and censoring processes conditioning on past treatment, and baseline and time-varying covariates. BP treatment was associated with the risk of overall infection in opposite directions in the unweighted Cox model {incidence rate ratio [IRR] [95% confidence interval (CI)] = 1.15 [1.14-1.17]} versus the weighted MSM [IRR (95% CI) = 0.79 (0.77-0.81)], but was consistently associated with a lower risk of serious infection in both the unweighted Cox model [IRR (95% CI] = 0.79 (0.78-0.81)) and the weighted MSM [IRR (95% CI) = 0.71 (0.68-0.75)]. Similar results were found when current and past treatments were simultaneously assessed. The discrepancy of effect estimates for overall but not serious infection comparing unweighted models and MSM suggested analyses of composite outcomes with a wide range of disease severity may be more susceptible to time-varying confounding.

  5. Regression model for the study of sole and cumulative effect of ...

    African Journals Online (AJOL)

    The effect of variability in temperature, solar radiation and photothermal quotient were studied under varying planting windows in three wheat genotypes to cope environmental vulnerability. Regression models are regarded as valuable tools for the evaluation of temperature, solar radiation and photothermal quotient effects ...

  6. EPA's SHEDS-multimedia model: children's cumulative pyrethroid exposure estimates and evaluation against NHANES biomarker data (United States)

    The U.S. EPA's SHEDS-Multimedia model was applied to enhance the understanding of children's exposures and doses to multiple pyrethroid pesticides, including major contributing chemicals and pathways. This paper presents combined dietary and residential exposure estimates and cum...

  7. Managing the Cumulative Impacts of Land Uses in the Western Canadian Sedimentary Basin: A Modeling Approach


    Richard, R. Schneider; J. Brad Stelfox; Stan Boutin; Shawn Wasel


    This case study from northeastern Alberta, Canada, demonstrates a fundamentally different approach to forest management in which stakeholders balance conservation and economic objectives by weighing current management options from the point of view of their long-term effects on the forest. ALCES®, a landscape-scale simulation model, is used to quantify the effects of the current regulatory framework and typical industrial practices on a suite of ecological and economic indicators over the nex...

  8. Using Marginal Structural Modeling to Estimate the Cumulative Impact of an Unconditional Tax Credit on Self-Rated Health. (United States)

    Pega, Frank; Blakely, Tony; Glymour, M Maria; Carter, Kristie N; Kawachi, Ichiro


    In previous studies, researchers estimated short-term relationships between financial credits and health outcomes using conventional regression analyses, but they did not account for time-varying confounders affected by prior treatment (CAPTs) or the credits' cumulative impacts over time. In this study, we examined the association between total number of years of receiving New Zealand's Family Tax Credit (FTC) and self-rated health (SRH) in 6,900 working-age parents using 7 waves of New Zealand longitudinal data (2002-2009). We conducted conventional linear regression analyses, both unadjusted and adjusted for time-invariant and time-varying confounders measured at baseline, and fitted marginal structural models (MSMs) that more fully adjusted for confounders, including CAPTs. Of all participants, 5.1%-6.8% received the FTC for 1-3 years and 1.8%-3.6% for 4-7 years. In unadjusted and adjusted conventional regression analyses, each additional year of receiving the FTC was associated with 0.033 (95% confidence interval (CI): -0.047, -0.019) and 0.026 (95% CI: -0.041, -0.010) units worse SRH (on a 5-unit scale). In the MSMs, the average causal treatment effect also reflected a small decrease in SRH (unstabilized weights: β = -0.039 unit, 95% CI: -0.058, -0.020; stabilized weights: β = -0.031 unit, 95% CI: -0.050, -0.007). Cumulatively receiving the FTC marginally reduced SRH. Conventional regression analyses and MSMs produced similar estimates, suggesting little bias from CAPTs. © The Author 2016. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail:

  9. Development of a "Hydrologic Equivalent Wetland" Concept for Modeling Cumulative Effects of Wetlands on Watershed Hydrology (United States)

    Wang, X.; Liu, T.; Li, R.; Yang, X.; Duan, L.; Luo, Y.


    Wetlands are one of the most important watershed microtopographic features that affect, in combination rather than individually, hydrologic processes (e.g., routing) and the fate and transport of constituents (e.g., sediment and nutrients). Efforts to conserve existing wetlands and/or to restore lost wetlands require that watershed-level effects of wetlands on water quantity and water quality be quantified. Because monitoring approaches are usually cost or logistics prohibitive at watershed scale, distributed watershed models, such as the Soil and Water Assessment Tool (SWAT), can be a best resort if wetlands can be appropriately represented in the models. However, the exact method that should be used to incorporate wetlands into hydrologic models is the subject of much disagreement in the literature. In addition, there is a serious lack of information about how to model wetland conservation-restoration effects using such kind of integrated modeling approach. The objectives of this study were to: 1) develop a "hydrologic equivalent wetland" (HEW) concept; and 2) demonstrate how to use the HEW concept in SWAT to assess effects of wetland restoration within the Broughton's Creek watershed located in southwestern Manitoba of Canada, and of wetland conservation within the upper portion of the Otter Tail River watershed located in northwestern Minnesota of the United States. The HEWs were defined in terms of six calibrated parameters: the fraction of the subbasin area that drains into wetlands (WET_FR), the volume of water stored in the wetlands when filled to their normal water level (WET_NVOL), the volume of water stored in the wetlands when filled to their maximum water level (WET_MXVOL), the longest tributary channel length in the subbasin (CH_L1), Manning's n value for the tributary channels (CH_N1), and Manning's n value for the main channel (CH_N2). The results indicated that the HEW concept allows the nonlinear functional relations between watershed processes

  10. Instrumental variables estimation of exposure effects on a time-to-event endpoint using structural cumulative survival models. (United States)

    Martinussen, Torben; Vansteelandt, Stijn; Tchetgen Tchetgen, Eric J; Zucker, David M


    The use of instrumental variables for estimating the effect of an exposure on an outcome is popular in econometrics, and increasingly so in epidemiology. This increasing popularity may be attributed to the natural occurrence of instrumental variables in observational studies that incorporate elements of randomization, either by design or by nature (e.g., random inheritance of genes). Instrumental variables estimation of exposure effects is well established for continuous outcomes and to some extent for binary outcomes. It is, however, largely lacking for time-to-event outcomes because of complications due to censoring and survivorship bias. In this article, we make a novel proposal under a class of structural cumulative survival models which parameterize time-varying effects of a point exposure directly on the scale of the survival function; these models are essentially equivalent with a semi-parametric variant of the instrumental variables additive hazards model. We propose a class of recursive instrumental variable estimators for these exposure effects, and derive their large sample properties along with inferential tools. We examine the performance of the proposed method in simulation studies and illustrate it in a Mendelian randomization study to evaluate the effect of diabetes on mortality using data from the Health and Retirement Study. We further use the proposed method to investigate potential benefit from breast cancer screening on subsequent breast cancer mortality based on the HIP-study. © 2017, The International Biometric Society.

  11. Managing the Cumulative Impacts of Land Uses in the Western Canadian Sedimentary Basin: A Modeling Approach

    Directory of Open Access Journals (Sweden)

    Richard, R. Schneider


    Full Text Available This case study from northeastern Alberta, Canada, demonstrates a fundamentally different approach to forest management in which stakeholders balance conservation and economic objectives by weighing current management options from the point of view of their long-term effects on the forest. ALCES®, a landscape-scale simulation model, is used to quantify the effects of the current regulatory framework and typical industrial practices on a suite of ecological and economic indicators over the next 100 yr. These simulations suggest that, if current practices continue, the combined activities of the energy and forestry industries in our 59,000 km2 study area will cause the density of edge of human origin to increase from 1.8 km/km 2 to a maximum of 8.0 km/km2. We also predict that older age classes of merchantable forest stands will be largely eliminated from the landscape, habitat availability for woodland caribou will decline from 43 to 6%, and there will be a progressive shortfall in the supply of softwood timber beginning in approximately 60 yr. Additional simulations involving a suite of "best practices" demonstrate that substantial improvements in ecological outcome measures could be achieved through alternative management scenarios while still maintaining a sustainable flow of economic benefits. We discuss the merits of our proposed approach to land use planning and apply it to the Western Canadian Sedimentary Basin.


    The US EPAs N-Methyl Carbamate Cumulative Risk Assessment (NMCRA) assesses the effect on acetylcholine esterase (AChE) activity of exposure to 10 N-methyl carbamate (NMC) pesticides through dietary, drinking water, and residential exposures.

  13. Failure-To-Thrive, Maltreatment and the Behavior and Development of 6-Year-Old Children from Low-Income, Urban Families: A Cumulative Risk Model. (United States)

    Kerr, Mia A.; Black, Maureen M.; Krishnakumar, Ambika


    A cumulative risk model was used to examine the relationship among failure-to-thrive (FIT), maltreatment, and four aspects of children's development (cognitive performance, adaptive functioning at school, classroom behavior, and behavior at home) in 193 6-year-olds. Risk status was negatively associated with the four developmental outcomes.…

  14. Combining Field and Modeling Tools As an Approach to Assess Cumulative Surface Erosion in Alberta Eastern Slopes and Foothills. (United States)

    Anderson, A.; Wagner, M. J.; Hirshfield, F.; Howard, M.; Silins, U.; Benda, L. E.


    Alberta is a large province with diverse forested landscapes and heavy industrial, range and recreation use. Hillslopes are generally stable but the cumulative surface erosion from bare areas (e.g. roads, well pad, trails, burns and pipelines) is a major concern for downstream water users, aquatic ecology and stream habitat. Most streams are not exhibiting issues from additional coarse soil (e.g. obvious changes to geomorphology) however, soils with high proportion of fines and phosphorus have been attributed to long lasting aquatic ecology impacts and associated downstream water quality issues. For this project we take a watershed scale approach to determine if we can reduce field effort by using high quality digital terrain data available for most of Alberta combined with tools such as the Geomorphic Road Analysis and Inventory Package (GRAIP) and landscape scale GIS assessment and modeling tools such as NetMap. We examine two contrasting regions of Alberta: (1) a tributary of the Oldman River in southwest Alberta that has steep topography, intense storms and heavy motorized recreation from the neighboring 1.5 Million people, and (2) the Foothills area that has fine lacustrine soil, low topography and extremely heavy industrial activity from energy, mining and forestry. We present the initial results of field data combined with GIS analysis for the eastern slopes as part of a larger project that is assessing these tools in represented end member watersheds for forested areas within the foothills and eastern slopes region (area of Alberta where watersheds have meaningful topography). Initial results suggest that GIS and associated modeling are very useful in providing rapid direction for field campaigns to refine the level of uncertainty, make prescriptive field plans and will likely be platforms that can track changes in predicated watershed scale erosion rates through time.

  15. Drawing a Seismic Source Zone Model Using Cumulative Seismic Moment Release and Moment Tensors in the Italian Peninsula (United States)

    Salimbeni, S.; Pondrelli, S.; D'Amico, V.; Meletti, C.; Rovida, A.


    In the frame of the elaboration of a new seismic hazard model of Italy, the identification of the areas with homogeneous tectonic regime is needed as one of the objective elements for designing the seismic source zones.A collection of all seismic moment tensors available for Italy for earthquakes with magnitude greater than or equal to 4.0 since 1960 was gathered. It contains data from different catalogs or datasets, mainly populated by moment tensors computed through inversion of seismic waves (e.g. CMT, RCMT, GFZ and ETHZ MT and so on). However, for great earthquakes of the past, i.e. the 1962 Irpinia or the 1968 Belice earthquakes (both max Mw > 6.0) we used data obtained with other methods, but always considered the best available information for that time.All these data helped to find the predominant fault mechanism, considered the typical tectonic style for a region or, using regular grids, for all seismic areas of the Italian peninsula and regions around. To identify the most seismic regions, we used data from historical and recent instrumental seismicity (CPTI15, and INGV bulletins, combined on a regular grid, obtaining seismic moment release maps. Overlapping cumulative moment tensors to seismic moment release maps, we identified regions clearly characterized by different tectonics. In particular, the extension is the principal type of deformation along most of the Apennines, somewhere interrupted by strike-slip mechanism. Compressive deformation appears in the eastern Alps, in the outer part of the northernmost sector of the Apennines, in several parts of the Adriatic Sea and in the off shore of Northern Sicily. We considered this tectonic style mapping to help with drawing seismic area sources for the new seismic hazard model of Italy.

  16. Using Physiologically-Based Pharmacokinetic Models to Incorporate Chemical and Non-Chemical Stressors into Cumulative Risk Assessment: A Case Study of Pesticide Exposures

    Directory of Open Access Journals (Sweden)

    Jonathan I. Levy


    Full Text Available Cumulative risk assessment has been proposed as an approach to evaluate the health risks associated with simultaneous exposure to multiple chemical and non-chemical stressors. Physiologically based pharmacokinetic/pharmacodynamic (PBPK/PD models can allow for the inclusion and evaluation of multiple stressors, including non-chemical stressors, but studies have not leveraged PBPK/PD models to jointly consider these disparate exposures in a cumulative risk context. In this study, we focused on exposures to organophosphate (OP pesticides for children in urban low-income environments, where these children would be simultaneously exposed to other pesticides (including pyrethroids and non-chemical stressors that may modify the effects of these exposures (including diet. We developed a methodological framework to evaluate chemical and non-chemical stressor impacts on OPs, utilizing an existing PBPK/PD model for chlorpyrifos. We evaluated population-specific stressors that would influence OP doses or acetylcholinesterase (AChE inhibition, the relevant PD outcome. We incorporated the impact of simultaneous exposure to pyrethroids and dietary factors on OP dose through the compartments of metabolism and PD outcome within the PBPK model, and simulated combinations of stressors across multiple exposure ranges and potential body weights. Our analyses demonstrated that both chemical and non-chemical stressors can influence the health implications of OP exposures, with up to 5-fold variability in AChE inhibition across combinations of stressor values for a given OP dose. We demonstrate an approach for modeling OP risks in the presence of other population-specific environmental stressors, providing insight about co-exposures and variability factors that most impact OP health risks and contribute to children’s cumulative health risk from pesticides. More generally, this framework can be used to inform cumulative risk assessment for any compound impacted by

  17. Switching From Age-Based Stimulus Dosing to Dose Titration Protocols in Electroconvulsive Therapy: Empirical Evidence for Better Patient Outcomes With Lower Peak and Cumulative Energy Doses. (United States)

    O'Neill-Kerr, Alex; Yassin, Anhar; Rogers, Stephen; Cornish, Janie


    The aim of this study was to test the proposition that adoption of a dose titration protocol may be associated with better patient outcomes, at lower treatment dose, and with comparable cumulative dose to that in patients treated using an age-based stimulus dosing protocol. This was an analysis of data assembled from archived records and based on cohorts of patients treated respectively on an age-based stimulus dosing protocol and on a dose titration protocol in the National Health Service in England. We demonstrated a significantly better response in the patient cohort treated with dose titration than with age-based stimulus dosing. Peak doses were less and the total cumulative dose was less in the dose titration group than in the age-based stimulus dosing group. Our findings are consistent with superior outcomes in patients treated using a dose titration protocol when compared with age-based stimulus dosing in a similar cohort of patients.

  18. Predictive modelling of evidence informed teaching


    Zhang, Dell; Brown, C.


    In this paper, we analyse the questionnaire survey data collected from 79 English primary schools about the situation of evidence informed teaching, where the evidences could come from research journals or conferences. Specifically, we build a predictive model to see what external factors could help to close the gap between teachers’ belief and behaviour in evidence informed teaching, which is the first of its kind to our knowledge. The major challenge, from the data mining perspective, is th...

  19. Natural arsenic attenuation via metal arsenate precipitation in soils contaminated with metallurgical wastes: II. Cumulative evidence and identification of minor processes

    International Nuclear Information System (INIS)

    Gutiérrez-Ruiz, M.E.; Ceniceros-Gómez, A.E.; Villalobos, M.; Romero, F.; Santiago, P.


    Highlights: ► Aqueous As in soils surrounding a smelting plant decreased through a natural attenuation process. ► As in water extracts from soils matched thermodynamic equilibrium modeling results. ► Modeling indicates that lead arsenates of low-solubility control As mobility. ► Sequential chemical extractions are consistent with the solubility behavior of lead arsenates. ► Microscopic evidence of lead arsenates was obtained by HRTEM–EDS. - Abstract: Accurate identification of individual As species in contaminated environments is critical because the toxicology, mobility and adsorptive properties of this element may vary substantially with its chemical forms and oxidation states. The goal of this work was to relate the geochemical behavior of As in soils contaminated by a lead smelter in Mexico, with its chemical speciation, and to achieve direct identification of low-solubility poorly-crystalline metal arsenates. Arsenic was identified as the most mobile trace element in the wastes from the smelting plant. Arsenic solubility in soils was significantly lower than its solubility in wastes, showing natural attenuation of this element. Its solubility in soil was quantitatively described in selected samples through thermodynamic equilibrium modeling. The results indicated that As solubility is controlled by solid Pb and Cu arsenate formation. The behaviors of the sequential chemical extractions were consistent with the presence of the predicted arsenates. Microscopic evidence of the formation of solid metal arsenates were obtained in fine soil fractions of selected samples with high As contents, by using the following complementary techniques: X-ray diffraction, scanning electron microscopy and transmission electron microscopy, both coupled with energy dispersive X-ray spectroscopy, and the latter with a high angle annular dark field detector. All results supported the formation of low-solubility Pb arsenates as controlling As mobility in the samples

  20. Modeling cumulative effects in life cycle assessment: the case of fertilizer in wheat production contributing to the global warming potential. (United States)

    Laratte, Bertrand; Guillaume, Bertrand; Kim, Junbeum; Birregah, Babiga


    This paper aims at presenting a dynamic indicator for life cycle assessment (LCA) measuring cumulative impacts over time of greenhouse gas (GHG) emissions from fertilizers used for wheat cultivation and production. Our approach offers a dynamic indicator of global warming potential (GWP), one of the most used indicator of environmental impacts (e.g. in the Kyoto Protocol). For a case study, the wheat production in France was selected and considered by using data from official sources about fertilizer consumption and production of wheat. We propose to assess GWP environmental impact based on LCA method. The system boundary is limited to the fertilizer production for 1 ton of wheat produced (functional unit) from 1910 to 2010. As applied to wheat production in France, traditional LCA shows a maximum GWP impact of 500 kg CO2-eq for 1 ton of wheat production, whereas the GWP impact of wheat production over time with our approach to dynamic LCA and its cumulative effects increases to 18,000 kg CO2-eq for 1 ton of wheat production. In this paper, only one substance and one impact assessment indicator are presented. However, the methodology can be generalized and improved by using different substances and indicators. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Subduction of shallowly formed arc cumulates: Evidence from clinopyroxene compositions of garnet peridotites in the Rio San Juan Complex, northern Dominican Republic (United States)

    Hattori, K.; Tubrett, M.; Saumur, B.-M.; Guillot, S.


    Garnet peridotites are very rare in oceanic subduction complexes, with only two reported occurrences. One is in the Sambagawa metamorphic belt in Shikoku, Japan, and the other example is in the southern part of the Rio Juan Complex, northern Dominican Republic. In both locations, garnet peridotite occurs in close association with eclogites in high metamorphic grade of the terranes. The Rio Juan Complex represents rocks formed during the southwestern subduction of the Proto-Caribbean oceanic plate below the Carribean Plate during late Cretaceous to early Eocene. Garnet peridotites (clinopyroxene[Cpx]-bearing dunite, wehrlite, olivine clinopyroxenite) occur as large (The rocks are all low in Ir-group PGE (Ir, Ru, Os), indicating that they are cumulates of a melt, since these remain in the residue during partial melting. A cumulate origin of the ultramafic rocks is consistent with relatively low Mg contents of olivine (Fo 74-83) compared to olivine in mantle peridotites. Extended trace element plots of the bulk rocks show a so-called "arc geochemical signature" with high fluid-mobile element concentrations, such as Sr, U, and Pb, and low HFSE, such as Nb and Zr, indicating that formation of the parental magmas were related to subduction. Two representative garnet-bearing samples (wehrlite and clinopyroxenite) were selected for trace element analysis of Cpx grains using a LA HR ICP-MS. The data show a negatively sloped normalized pattern of REE; low contents of light REE (0.1-0.3 of the primitive mantle values) and similar concentrations of middle to heavy REE (1-2 of the primitive mantle values). Extended trace element patterns of Cpx are similar between two samples and also to that of the bulk rocks, with low Nb and Zr and high fluid-mobile elements. The Y and heavy REE patterns of Cpx do not show anomalies between the samples. As these elements would be preferentially incorporated into garnet, the lack of anomalies indicates early crystallization of Cpx and later

  2. Comparison between Einstein and Debye models for an amorphous Ni46Ti54 alloy produced by mechanical alloying investigated using extended x-ray absorption fine structure and cumulant expansion. (United States)

    Machado, K D


    We investigated an amorphous Ni(46)Ti(54) alloy produced by mechanical alloying using extended x-ray absorption fine structure (EXAFS) technique and cumulant expansion considering Einstein and Debye models for the temperature dependence of the cumulants. Results obtained from both models were compared and very similar values were obtained. From them, we found information about the structure of the alloy besides thermal and structural disorder, anharmonicity, thermal expansion, and asymmetry of the partial distribution functions g(ij)(r). The cumulants C(1)(*), C(2)(*), and C(3)(*) also allowed us to reconstruct the g(ij)(r, T) functions from EXAFS.

  3. Modelling the changing cumulative vulnerability to climate-related hazards for river basin management using a GIS-based multicriteria decision approach (United States)

    Hung, Hung-Chih; Wu, Ju-Yu; Hung, Chih-Hsuan


    1. Background Asia-Pacific region is one of the most vulnerable areas of the world to climate-related hazards and extremes due to rapid urbanization and over-development in hazard-prone areas. It is thus increasingly recognized that the management of land use and reduction of hazard risk are inextricably linked. This is especially critical from the perspective of integrated river basin management. A range of studies has targeted existing vulnerability assessments. However, limited attention has been paid to the cumulative effects of multiple vulnerable factors and their dynamics faced by local communities. This study proposes a novel methodology to access the changing cumulative vulnerability to climate-related hazards, and to examine the relationship between the attraction factors relevant to the general process of urbanization and vulnerability variability with a focus on a river basin management unit. 2. Methods and data The methods applied in this study include three steps. First, using Intergovernmental Panel on Climate Change's (IPCC) approach, a Cumulative Vulnerability Assessment Framework (CVAF) is built with a goal to characterize and compare the vulnerability to climate-related hazards within river basin regions based on a composition of multiple indicators. We organize these indicator metrics into three categories: (1) hazard exposure; (2) socioeconomic sensitivity, and (3) adaptive capacity. Second, the CVAF is applied by combining a geographical information system (GIS)-based spatial statistics technique with a multicriteria decision analysis (MCDA) to assess and map the changing cumulative vulnerability, comparing conditions in 1996 and 2006 in Danshui River Basin, Taiwan. Third, to examine the affecting factors of vulnerability changing, we develop a Vulnerability Changing Model (VCM) using four attraction factors to reflect how the process of urban developments leads to vulnerability changing. The factors are transport networks, land uses

  4. A pore structure model for the gas transport property changes, initial oxidation rates and cumulative weight loss of AGR moderator graphite

    International Nuclear Information System (INIS)

    Johnson, P.A.V.


    A quantitative model has been developed for the gas transport property variation, cumulative weight loss and initial oxidation rates of AGR moderator graphite. The model utilises the theory of dynamic moments of the pore structure to calculate the changes in physical properties brought about by radiolytic corrosion taking place within the graphite porosity. In order to account for the behaviour of the initial rate curves, and the weight loss data obtained it is necessary to invoke the presence of a group of cylindrical pore and a group of small slab-shaped pores. The latter are methane depleted. This is in addition to the pore group involved in gas transport which is best represented by cylinders of mean radius 2.13 μm. The model satisfactorily predicts the experimental weight loss data obtained from experiments in the DIDO 6V3 and BFB loops. (author)

  5. Comparative Risks of Cancer from Drywall Finishing Based on Stochastic Modeling of Cumulative Exposures to Respirable Dusts and Chrysotile Asbestos Fibers. (United States)

    Boelter, Fred W; Xia, Yulin; Dell, Linda


    Sanding joint compounds is a dusty activity and exposures are not well characterized. Until the mid 1970s, asbestos-containing joint compounds were used by some people such that sanding could emit dust and asbestos fibers. We estimated the distribution of 8-h TWA concentrations and cumulative exposures to respirable dusts and chrysotile asbestos fibers for four worker groups: (1) drywall specialists, (2) generalists, (3) tradespersons who are bystanders to drywall finishing, and (4) do-it-yourselfers (DIYers). Data collected through a survey of experienced contractors, direct field observations, and literature were used to develop prototypical exposure scenarios for each worker group. To these exposure scenarios, we applied a previously developed semi-empirical mathematical model that predicts area as well as personal breathing zone respirable dust concentrations. An empirical factor was used to estimate chrysotile fiber concentrations from respirable dust concentrations. On a task basis, we found mean 8-h TWA concentrations of respirable dust and chrysotile fibers are numerically highest for specialists, followed by generalists, DIYers, and bystander tradespersons; these concentrations are estimated to be in excess of the respective current but not historical Threshold Limit Values. Due to differences in frequency of activities, annual cumulative exposures are highest for specialists, followed by generalists, bystander tradespersons, and DIYers. Cumulative exposure estimates for chrysotile fibers from drywall finishing are expected to result in few, if any, mesothelioma or excess lung cancer deaths according to recently published risk assessments. Given the dustiness of drywall finishing, we recommend diligence in the use of readily available source controls. © 2014 Society for Risk Analysis.

  6. Physics-Based Stress Corrosion Cracking Component Reliability Model cast in an R7-Compatible Cumulative Damage Framework

    Energy Technology Data Exchange (ETDEWEB)

    Unwin, Stephen D.; Lowry, Peter P.; Layton, Robert F.; Toloczko, Mychailo B.; Johnson, Kenneth I.; Sanborn, Scott E.


    This is a working report drafted under the Risk-Informed Safety Margin Characterization pathway of the Light Water Reactor Sustainability Program, describing statistical models of passives component reliabilities.

  7. Accounting for partial sleep deprivation and cumulative sleepiness in the Three-Process Model of alertness regulation. (United States)

    Akerstedt, Torbjörn; Ingre, Michael; Kecklund, Göran; Folkard, Simon; Axelsson, John


    Mathematical models designed to predict alertness or performance have been developed primarily as tools for evaluating work and/or sleep-wake schedules that deviate from the traditional daytime orientation. In general, these models cope well with the acute changes resulting from an abnormal sleep but have difficulties handling sleep restriction across longer periods. The reason is that the function representing recovery is too steep--usually exponentially so--and with increasing sleep loss, the steepness increases, resulting in too rapid recovery. The present study focused on refining the Three-Process Model of alertness regulation. We used an experiment with 4 h of sleep/night (nine participants) that included subjective self-ratings of sleepiness every hour. To evaluate the model at the individual subject level, a set of mixed-effect regression analyses were performed using subjective sleepiness as the dependent variable. These mixed models estimate a fixed effect (group mean) and a random effect that accounts for heterogeneity between participants in the overall level of sleepiness (i.e., a random intercept). Using this technique, a point was sought on the exponential recovery function that would explain maximum variance in subjective sleepiness by switching to a linear function. The resulting point explaining the highest amount of variance was 12.2 on the 1-21 unit scale. It was concluded that the accumulation of sleep loss effects on subjective sleepiness may be accounted for by making the recovery function linear below a certain point on the otherwise exponential function.

  8. Dark energy observational evidence and theoretical models

    CERN Document Server

    Novosyadlyj, B; Shtanov, Yu; Zhuk, A


    The book elucidates the current state of the dark energy problem and presents the results of the authors, who work in this area. It describes the observational evidence for the existence of dark energy, the methods and results of constraining of its parameters, modeling of dark energy by scalar fields, the space-times with extra spatial dimensions, especially Kaluza---Klein models, the braneworld models with a single extra dimension as well as the problems of positive definition of gravitational energy in General Relativity, energy conditions and consequences of their violation in the presence of dark energy. This monograph is intended for science professionals, educators and graduate students, specializing in general relativity, cosmology, field theory and particle physics.

  9. Family Resources and Effects on Child Behavior Problem Interventions: A Cumulative Risk Approach. (United States)

    Tømmerås, Truls; Kjøbli, John


    Family resources have been associated with health care inequality in general and with social gradients in treatment outcomes for children with behavior problems. However, there is limited evidence concerning cumulative risk-the accumulation of social and economic disadvantages in a family-and whether cumulative risk moderates the outcomes of evidence-based parent training interventions. We used data from two randomized controlled trials evaluating high-intensity ( n  = 137) and low-intensity ( n  = 216) versions of Parent Management Training-Oregon (PMTO) with a 50:50 allocation between participants receiving PMTO interventions or regular care. A nine-item family cumulative risk index tapping socioeconomic resources and parental health was constructed to assess the family's exposure to risk. Autoregressive structured equation models (SEM) were run to investigate whether cumulative risk moderated child behaviors at post-treatment and follow-up (6 months). Our results showed opposite social gradients for the treatment conditions: the children exposed to cumulative risk in a pooled sample of both PMTO groups displayed lower levels of behavior problems, whereas children with identical risk exposures who received regular care experienced more problems. Furthermore, our results indicated that the social gradients differed between PMTO interventions: children exposed to cumulative risk in the low-intensity (five sessions) Brief Parent Training fared equally well as their high-resource counterparts, whereas children exposed to cumulative risk in the high-intensity PMTO (12 sessions) experienced vastly better treatment effects. Providing evidence-based parent training seem to be an effective way to counteract health care inequality, and the more intensive PMTO treatment seemed to be a particularly effective way to help families with cumulative risk.

  10. Using simulation models to investigate the cumulative effects of sowing rate, sowing date and cultivar choice on weed competition. (United States)

    Andrew, Izzadora K S; Storkey, Jonathan


    With the increasing pressure on crop production from the evolution of herbicide resistance, farmers are increasingly adopting Integrated Weed Management (IWM) strategies to augment their weed control. These include measures to increase the competitiveness of the crop canopy such as increased sowing rate and the use of more competitive cultivars. While there are data on the relative impact of these non-chemical weed control methods assessed in isolation, there is uncertainty about their combined contribution, which may be hindering their adoption. In this article, the INTERCOM simulation model of crop/weed competition was used to examine the combined impact of crop density, sowing date and cultivar choice on the outcomes of competition between wheat ( Triticum aestivum ) and Alopecurus myosuroides . Alopecurus myosuroides is a problematic weed of cereal crops in North-Western Europe and the primary target for IWM in the UK because it has evolved resistance to a range of herbicides. The model was parameterised for two cultivars with contrasting competitive ability, and simulations run across 10 years at different crop densities and two sowing dates. The results suggest that sowing date, sowing density and cultivar choice largely work in a complementary fashion, allowing enhanced competitive ability against weeds when used in combination. However, the relative benefit of choosing a more competitive cultivar decreases at later sowing dates and higher crop densities. Modeling approaches could be further employed to examine the effectiveness of IWM, reducing the need for more expensive and cumbersome long-term in situ experimentation.


    Bowerman, P. N.


    The cumulative binomial program, CUMBIN, is one of a set of three programs which calculate cumulative binomial probability distributions for arbitrary inputs. The three programs, CUMBIN, NEWTONP (NPO-17556), and CROSSER (NPO-17557), can be used independently of one another. CUMBIN can be used by statisticians and users of statistical procedures, test planners, designers, and numerical analysts. The program has been used for reliability/availability calculations. CUMBIN calculates the probability that a system of n components has at least k operating if the probability that any one operating is p and the components are independent. Equivalently, this is the reliability of a k-out-of-n system having independent components with common reliability p. CUMBIN can evaluate the incomplete beta distribution for two positive integer arguments. CUMBIN can also evaluate the cumulative F distribution and the negative binomial distribution, and can determine the sample size in a test design. CUMBIN is designed to work well with all integer values 0 < k <= n. To run the program, the user simply runs the executable version and inputs the information requested by the program. The program is not designed to weed out incorrect inputs, so the user must take care to make sure the inputs are correct. Once all input has been entered, the program calculates and lists the result. The CUMBIN program is written in C. It was developed on an IBM AT with a numeric co-processor using Microsoft C 5.0. Because the source code is written using standard C structures and functions, it should compile correctly with most C compilers. The program format is interactive. It has been implemented under DOS 3.2 and has a memory requirement of 26K. CUMBIN was developed in 1988.

  12. A paradox of cumulative culture. (United States)

    Kobayashi, Yutaka; Wakano, Joe Yuichiro; Ohtsuki, Hisashi


    Culture can grow cumulatively if socially learnt behaviors are improved by individual learning before being passed on to the next generation. Previous authors showed that this kind of learning strategy is unlikely to be evolutionarily stable in the presence of a trade-off between learning and reproduction. This is because culture is a public good that is freely exploited by any member of the population in their model (cultural social dilemma). In this paper, we investigate the effect of vertical transmission (transmission from parents to offspring), which decreases the publicness of culture, on the evolution of cumulative culture in both infinite and finite population models. In the infinite population model, we confirm that culture accumulates largely as long as transmission is purely vertical. It turns out, however, that introduction of even slight oblique transmission drastically reduces the equilibrium level of culture. Even more surprisingly, if the population size is finite, culture hardly accumulates even under purely vertical transmission. This occurs because stochastic extinction due to random genetic drift prevents a learning strategy from accumulating enough culture. Overall, our theoretical results suggest that introducing vertical transmission alone does not really help solve the cultural social dilemma problem. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Modeling a Conventional Electroporation Pulse Train: Decreased Pore Number, Cumulative Calcium Transport and an Example of Electrosensitization. (United States)

    Son, Reuben S; Gowrishankar, Thiruvallur R; Smith, Kyle C; Weaver, James C


    Pulse trains are widely used in electroporation (EP) for both general biomedical research and clinical applications such as nonthermal tumor ablation. Here we use a computational method based on a meshed transport network to investigate a cell system model's response to a train of identical, evenly spaced electric field pulses. We obtain an unexpected result: the number of membrane pores decreases during the application of twenty 1.0 kV/cm, 100 μs pulses, delivered at 1 Hz. This pulse train initially creates 13,000 membrane pores, but pore number decreases by a factor of 15 to about 830 pores throughout subsequent pulses. We conclude that pore number can greatly diminish during a train of identical pulses, with direct consequences for the transport of solutes across an electroporated membrane. Although application of additional pulses is generally intended to increase the effects of EP, we show that these pulses do not significantly enhance calcium delivery into the cell. Instead, calcium delivery can be significantly increased by varying inter-pulse intervals. We show that inserting a 300-s interruption midway in a widely used eight-pulse train (a protocol for electrosensitization) yields a ∼ twofold delivery increase. Overall, our modeling shows support for electrosensitization, in which multiple pulse protocols that maximize pore number over time can yield significant increase of transport of calcium compared to standard pulse trains.

  14. Cumulative impact of health deficits, social vulnerabilities, and protective factors on cognitive dynamics in late life: a multistate modeling approach. (United States)

    Armstrong, Joshua J; Mitnitski, Arnold; Andrew, Melissa K; Launer, Lenore J; White, Lon R; Rockwood, Kenneth


    Many factors influence late-life cognitive changes, and evaluating their joint impact is challenging. Typical approaches focus on average decline and a small number of factors. We used multistate transition models and index variables to look at changes in cognition in relation to frailty (accumulation of health deficits), social vulnerability, and protective factors in the Honolulu-Asia Aging Study (HAAS). The HAAS is a prospective cohort study of 3,845 men of Japanese descent, aged 71 to 93 years at baseline. Cognitive function was measured using the Cognitive Abilities Screening Instrument (CASI). Baseline index variables were constructed of health deficits (frailty), social vulnerabilities, and protective factors. The chances of improvement/stability/decline in cognitive function and death were simultaneously estimated using multistate transition modeling for 3- and 6-year transitions from baseline. On average, CASI scores declined by 5.3 points (standard deviation (SD) = 10.0) over 3 years and 9.5 points (SD = 13.9) over 6 years. After adjusting for education and age, baseline frailty was associated with an increased risk of cognitive decline at 3 years (β = 0.18, 95% confidence interval (CI), 0.08 to 0.29) and 6 years (β = 0.40, 95% CI, 0.27 to 0.54). The social vulnerability index was associated with 3-year changes (β = 0.16, 95% CI, 0.09 to 0.23) and 6-year changes (β = 0.14, 95% CI, 0.05 to 0.24) in CASI scores. The protective index was associated with reductions in cognitive decline over the two intervals (3-year: β = -0.16, 95% CI, -0.24 to -0.09; 6-year: β = -0.21, 95% CI, -0.31 to -0.11,). Research on cognition in late life needs to consider overall health, the accumulation of protective factors, and the dynamics of cognitive change. Index variables and multistate transition models can enhance understanding of the multifactorial nature of late-life changes in cognition.

  15. Psychometric properties of the Cumulated Ambulation Score

    DEFF Research Database (Denmark)

    Ferriero, Giorgio; Kristensen, Morten T; Invernizzi, Marco


    . EVIDENCE ACQUISITION: A literature search was conducted on research articles published between 2006 and June 2016 in journals indexed by MEDLINE and Scopus databases using as search item: "Cumulated Ambulation Score"[All Fields], and selecting studies that presented a psychometric analysis of the scale...


    Bowerman, P. N.


    The cumulative binomial program, CROSSER, is one of a set of three programs which calculate cumulative binomial probability distributions for arbitrary inputs. The three programs, CROSSER, CUMBIN (NPO-17555), and NEWTONP (NPO-17556), can be used independently of one another. CROSSER can be used by statisticians and users of statistical procedures, test planners, designers, and numerical analysts. The program has been used for reliability/availability calculations. CROSSER calculates the point at which the reliability of a k-out-of-n system equals the common reliability of the n components. It is designed to work well with all integer values 0 < k <= n. To run the program, the user simply runs the executable version and inputs the information requested by the program. The program is not designed to weed out incorrect inputs, so the user must take care to make sure the inputs are correct. Once all input has been entered, the program calculates and lists the result. It also lists the number of iterations of Newton's method required to calculate the answer within the given error. The CROSSER program is written in C. It was developed on an IBM AT with a numeric co-processor using Microsoft C 5.0. Because the source code is written using standard C structures and functions, it should compile correctly with most C compilers. The program format is interactive. It has been implemented under DOS 3.2 and has a memory requirement of 26K. CROSSER was developed in 1988.

  17. Electrical-modelling, design and simulation of cumulative radiation effects in semiconductor pixels detectors: prospects and limits (United States)

    Fourches, N. T.; Chipaux, R.


    Silicon detectors have gained in popularity since silicon became a widely used electronic semiconductor material. Silicon detectors are used in particle physics as well as imagers for pixel based detecting systems. Over the past twenty years a lot of experimental efforts have been focused on the effects of ionizing and non-ionizing radiation on silicon based detectors including charged coupled devices (CCDs). Some of this research was performed in the framework of high luminosity particle physics experiments, along with radiation hardness studies of basic semiconductors devices. The building blocks of silicon pixel detectors including CCDs are simple PIN or PN structures partially or totally depleted, or even MOS and APD (Avalanche PhotoDiode) structures. Bulk or surface defects considerably affect the transport of free carriers. We propose here guidelines for pixel design. The method takes into account the properties of defects and will be tested through two pixel structures. The electrical properties of defects can be reduced to basic parameters, which can be introduced in a standard simulation code to make predictive simulations. We include an analytical model for defect build up derived from isochronal annealing experiments. Studying pixels detectors with different geometrical structures and fabricated with various semiconducting materials is made possible with this method. Its purpose is to provide an alternative to tedious and extensive radiation tests on fabricated detectors. Predicting the pixel behaviour w.r.t. defect properties is necessary for the long-term reliability of detectors and for making them radiation hard. A general method for pixel design is introduced and we will show how it can be used for the design of alternative (germanium) pixels.

  18. Bayesian Model Selection in Geophysics: The evidence (United States)

    Vrugt, J. A.


    Bayesian inference has found widespread application and use in science and engineering to reconcile Earth system models with data, including prediction in space (interpolation), prediction in time (forecasting), assimilation of observations and deterministic/stochastic model output, and inference of the model parameters. Per Bayes theorem, the posterior probability, , P(H|D), of a hypothesis, H, given the data D, is equivalent to the product of its prior probability, P(H), and likelihood, L(H|D), divided by a normalization constant, P(D). In geophysics, the hypothesis, H, often constitutes a description (parameterization) of the subsurface for some entity of interest (e.g. porosity, moisture content). The normalization constant, P(D), is not required for inference of the subsurface structure, yet of great value for model selection. Unfortunately, it is not particularly easy to estimate P(D) in practice. Here, I will introduce the various building blocks of a general purpose method which provides robust and unbiased estimates of the evidence, P(D). This method uses multi-dimensional numerical integration of the posterior (parameter) distribution. I will then illustrate this new estimator by application to three competing subsurface models (hypothesis) using GPR travel time data from the South Oyster Bacterial Transport Site, in Virginia, USA. The three subsurface models differ in their treatment of the porosity distribution and use (a) horizontal layering with fixed layer thicknesses, (b) vertical layering with fixed layer thicknesses and (c) a multi-Gaussian field. The results of the new estimator are compared against the brute force Monte Carlo method, and the Laplace-Metropolis method.

  19. Cumulative cultural evolution: the role of teaching. (United States)

    Castro, Laureano; Toro, Miguel A


    In humans, cultural transmission occurs usually by cumulative inheritance, generating complex adaptive behavioral features. Cumulative culture requires key psychological processes (fundamentally imitation and teaching) that are absent or impoverished in non-human primates. In this paper we analyze the role that teaching has played in human cumulative cultural evolution. We assume that a system of cumulative culture generates increasingly adaptive behaviors, that are also more complex and difficult to imitate. Our thesis is that, as cultural traits become more complex, cumulative cultural transmission requires teaching to ensure accurate transmission from one generation to the next. In an increasingly complex cultural environment, we consider that individuals commit errors in imitation. We develop a model of cumulative cultural evolution in a changing environment and show that these errors hamper the process of cultural accumulation. We also show that a system of teaching between parents and offspring that increases the fidelity of imitation unblocks the accumulation and becomes adaptive whenever the gain in fitness compensates the cost of teaching. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Cumulative environmental effects. Summary

    International Nuclear Information System (INIS)


    This report presents a compilation of knowledge about the state of the environment and human activity in the Norwegian part of the North Sea and Skagerrak. The report gives an overview of pressures and impacts on the environment from normal activity and in the event of accidents. This is used to assess the cumulative environmental effects, which factors have most impact and where the impacts are greatest, and to indicate which problems are expected to be most serious in the future. The report is intended to provide relevant information that can be used in the management of the marine area in the future. It also provides input for the identification of environmental targets and management measures for the North Sea and Skagerrak.(Author)

  1. Cumulative environmental effects. Summary

    Energy Technology Data Exchange (ETDEWEB)



    This report presents a compilation of knowledge about the state of the environment and human activity in the Norwegian part of the North Sea and Skagerrak. The report gives an overview of pressures and impacts on the environment from normal activity and in the event of accidents. This is used to assess the cumulative environmental effects, which factors have most impact and where the impacts are greatest, and to indicate which problems are expected to be most serious in the future. The report is intended to provide relevant information that can be used in the management of the marine area in the future. It also provides input for the identification of environmental targets and management measures for the North Sea and Skagerrak.(Author)


    Bowerman, P. N.


    The cumulative binomial program, NEWTONP, is one of a set of three programs which calculate cumulative binomial probability distributions for arbitrary inputs. The three programs, NEWTONP, CUMBIN (NPO-17555), and CROSSER (NPO-17557), can be used independently of one another. NEWTONP can be used by statisticians and users of statistical procedures, test planners, designers, and numerical analysts. The program has been used for reliability/availability calculations. NEWTONP calculates the probably p required to yield a given system reliability V for a k-out-of-n system. It can also be used to determine the Clopper-Pearson confidence limits (either one-sided or two-sided) for the parameter p of a Bernoulli distribution. NEWTONP can determine Bayesian probability limits for a proportion (if the beta prior has positive integer parameters). It can determine the percentiles of incomplete beta distributions with positive integer parameters. It can also determine the percentiles of F distributions and the midian plotting positions in probability plotting. NEWTONP is designed to work well with all integer values 0 < k <= n. To run the program, the user simply runs the executable version and inputs the information requested by the program. NEWTONP is not designed to weed out incorrect inputs, so the user must take care to make sure the inputs are correct. Once all input has been entered, the program calculates and lists the result. It also lists the number of iterations of Newton's method required to calculate the answer within the given error. The NEWTONP program is written in C. It was developed on an IBM AT with a numeric co-processor using Microsoft C 5.0. Because the source code is written using standard C structures and functions, it should compile correctly with most C compilers. The program format is interactive. It has been implemented under DOS 3.2 and has a memory requirement of 26K. NEWTONP was developed in 1988.

  3. Assessment of the role of ageing and non-ageing factors in death from non-communicable diseases based on a cumulative frequency model. (United States)

    Hui, Liu


    To quantify the effects of ageing and non-ageing factors, a characterization of the effects of ageing, genetic, and exogenous variables on 12 major non-communicable diseases was evaluated using a model assessing cumulative frequency of death and survival by age group from dead and surviving populations based on mortality statistics. Indices (0-1) of the roles of ageing (ARD), genetics (GRD) and exogenous (ERD) variables in deaths due to disease were established, and the sum of ARD, GRD and ERD was 1 (value of each indices was <1). Results showed that ageing plays an important role in death from chronic disease; exogenous factors may contribute more to the pattern of chronic disease than genetic factors (ARD, GRC and ERD were 0.818, 0.058 and 0.124 respectively for all non-communicable diseases). In descending order, ERD for non-communicable diseases were breast cancer, leukaemia, cancer of the cervix uteri and uterus, liver cancer, nephritis and nephropathy, stomach cancer, lung cancer, diabetes, cerebrovascular disease, coronary heart disease, COPD, and Alzheimer's disease, while a smaller ERD indicated a tendency of natural death. An understanding of the aforementioned complex relationships of specific non-communicable diseases will be beneficial in designing primary prevention measures for non-communicable diseases in China.

  4. A Framework for Treating Cumulative Trauma with Art Therapy (United States)

    Naff, Kristina


    Cumulative trauma is relatively undocumented in art therapy practice, although there is growing evidence that art therapy provides distinct benefits for resolving various traumas. This qualitative study proposes an art therapy treatment framework for cumulative trauma derived from semi-structured interviews with three art therapists and artistic…

  5. Editorial The importance of cumulative meta-analyses and ...

    African Journals Online (AJOL)

    for research. Furthermore, ignoring clinical trial evidence of benefit is unethical and negatively impacts on public health. Cumulative meta-analyses have contributed substantially to ... a cumulative meta-analysis of the use of oral beta blockers for ... survival benefit, with only 3 522 patients randomised.1,2 However, clinical ...

  6. A bivariate optimal replacement policy with cumulative repair cost ...

    Indian Academy of Sciences (India)

    Min-Tsai Lai

    Shock model; cumulative damage model; cumulative repair cost limit; preventive maintenance model. 1. Introduction. Most production systems are repaired or replaced when they have already failed. However, they may require much time and high expenses to repair a failed system, so maintaining a system to prevent ...

  7. Cumulative radiation effect

    International Nuclear Information System (INIS)

    Kirk, J.; Gray, W.M.; Watson, E.R.


    In five previous papers, the concept of Cumulative Radiation Effect (CRE) has been presented as a scale of accumulative sub-tolerance radiation damage, with a unique value of the CRE describing a specific level of radiation effect. Simple nomographic and tabular methods for the solution of practical problems in radiotherapy are now described. An essential feature of solving a CRE problem is firstly to present it in a concise and readily appreciated form, and, to do this, nomenclature has been introduced to describe schedules and regimes as compactly as possible. Simple algebraic equations have been derived to describe the CRE achieved by multi-schedule regimes. In these equations, the equivalence conditions existing at the junctions between schedules are not explicit and the equations are based on the CREs of the constituent schedules assessed individually without reference to their context in the regime as a whole. This independent evaluation of CREs for each schedule has resulted in a considerable simplification in the calculation of complex problems. The calculations are further simplified by the use of suitable tables and nomograms, so that the mathematics involved is reduced to simple arithmetical operations which require at the most the use of a slide rule but can be done by hand. The order of procedure in the presentation and calculation of CRE problems can be summarised in an evaluation procedure sheet. The resulting simple methods for solving practical problems of any complexity on the CRE-system are demonstrated by a number of examples. (author)

  8. Mission Availability for Bounded-Cumulative-Downtime System (United States)

    Zhou, Yu; Kou, Gang; Ergu, Daji; Peng, Yi


    In this research, a mathematics model is proposed to describe the mission availability for bounded-cumulative-downtime system. In the proposed model, the cumulative downtime and cumulative uptime are considered as constraints simultaneously. The mission availability can be defined as the probability that all repairs do not exceed the bounded cumulative downtime constraint of such system before the cumulative uptime has accrued. There are two mutually exclusive cases associated with the probability. One case is the system has not failed, where the probability can be described by system reliability. The other case is the system has failed and the cumulative downtime does not exceed the constraint before the cumulative uptime has accrued. The mathematic description of the probability under the second case is very complex. And the cumulative downtime in a mission can be set as a random variable, whose cumulative distribution means the probability that the failure system can be restored to the operating state. Giving the dependence in the scheduled mission, a mission availability model with closed form expression under this assumption is proposed. Numerical simulations are presented to illustrate the effectiveness of the proposed model. The results indicate that the relative errors are acceptable and the proposed model is effective. Furthermore, three important applications of the proposed mission availability model are discussed. PMID:23843940

  9. Seasonal climate change patterns due to cumulative CO2 emissions (United States)

    Partanen, Antti-Ilari; Leduc, Martin; Damon Matthews, H.


    Cumulative CO2 emissions are near linearly related to both global and regional changes in annual-mean surface temperature. These relationships are known as the transient climate response to cumulative CO2 emissions (TCRE) and the regional TCRE (RTCRE), and have been shown to remain approximately constant over a wide range of cumulative emissions. Here, we assessed how well this relationship holds for seasonal patterns of temperature change, as well as for annual-mean and seasonal precipitation patterns. We analyzed an idealized scenario with CO2 concentration growing at an annual rate of 1% using data from 12 Earth system models from the Coupled Model Intercomparison Project Phase 5 (CMIP5). Seasonal RTCRE values for temperature varied considerably, with the highest seasonal variation evident in the Arctic, where RTCRE was about 5.5 °C per Tt C for boreal winter and about 2.0 °C per Tt C for boreal summer. Also the precipitation response in the Arctic during boreal winter was stronger than during other seasons. We found that emission-normalized seasonal patterns of temperature change were relatively robust with respect to time, though they were sub-linear with respect to emissions particularly near the Arctic. Moreover, RTCRE patterns for precipitation could not be quantified robustly due to the large internal variability of precipitation. Our results suggest that cumulative CO2 emissions are a useful metric to predict regional and seasonal changes in precipitation and temperature. This extension of the TCRE framework to seasonal and regional climate change is helpful for communicating the link between emissions and climate change to policy-makers and the general public, and is well-suited for impact studies that could make use of estimated regional-scale climate changes that are consistent with the carbon budgets associated with global temperature targets.

  10. Cumulative radiation effect

    International Nuclear Information System (INIS)

    Kirk, J.; Cain, O.; Gray, W.M.


    Cumulative Radiation Effect (CRE) represents a scale of accumulative sub-tolerance radiation damage, with a unique value of the CRE describing a specific level of radiation effect. Computer calculations have been used to simplify the evaluation of problems associated with the applications of the CRE-system in radiotherapy. In a general appraisal of the applications of computers to the CRE-system, the various problems encountered in clinical radiotherapy have been categorised into those involving the evaluation of a CRE at a point in tissue and those involving the calculation of CRE distributions. As a general guide, the computer techniques adopted at the Glasgow Institute of Radiotherapeutics for the solution of CRE problems are presented, and consist basically of a package of three interactive programs for point CRE calculations and a Fortran program which calculates CRE distributions for iso-effect treatment planning. Many examples are given to demonstrate the applications of these programs, and special emphasis has been laid on the problem of treating a point in tissue with different doses per fraction on alternate treatment days. The wide range of possible clinical applications of the CRE-system has been outlined and described under the categories of routine clinical applications, retrospective and prospective surveys of patient treatment, and experimental and theoretical research. Some of these applications such as the results of surveys and studies of time optimisation of treatment schedules could have far-reaching consequences and lead to significant improvements in treatment and cure rates with the minimum damage to normal tissue. (author)

  11. Integrating LANDIS model and a multi-criteria decision-making approach to evaluate cumulative effects of forest management in the Missouri Ozarks, USA (United States)

    Zong Bo Shang; Hong S. He; Weimin Xi; Stephen R. Shifley; Brian J. Palik


    Public forest management requires consideration of numerous objectives including protecting ecosystem health, sustaining habitats for native communities, providing sustainable forest products, and providing noncommodity ecosystem services. It is difficult to evaluate the long-term, cumulative effects and tradeoffs these and other associated management objectives. To...

  12. Population dynamics models based on cumulative density dependent feedback: A link to the logistic growth curve and a test for symmetry using aphid data

    NARCIS (Netherlands)

    Matis, J.H.; Kiffe, T.R.; Werf, van der W.; Costamagna, A.C.; Matis, T.I.; Grant, W.E.


    Density dependent feedback, based on cumulative population size, has been advocated to explain and mathematically characterize “boom and bust” population dynamics. Such feedback results in a bell-shaped population trajectory of the population density. Here, we note that this trajectory is

  13. Cumulative Intracranial Tumor Volume Augments the Prognostic Value of Diagnosis-Specific Graded Prognostic Assessment Model for Survival in Patients with Melanoma Cerebral Metastases

    DEFF Research Database (Denmark)

    Hirshman, Brian R; Wilson, Bayard R; Ali, Mir Amaan


    BACKGROUND: The diagnosis-specific graded prognostic assessment scale (ds-GPA) for patients with melanoma brain metastasis (BM) utilizes only 2 key prognostic variables: Karnofsky performance status and the number of intracranial metastases. We wished to determine whether inclusion of cumulative ...

  14. Evaluating Cumulative Ecosystem Response to Restoration Projects in the Lower Columbia River and Estuary, 2008

    International Nuclear Information System (INIS)

    Johnson, Gary E.; Diefenderfer, Heida L.; Borde, Amy B.; Dawley, Earl M.; Ebberts, Blaine D.; Roegner, G. Curtis; Russell, Micah T.; Skalski, John R.; Thom, Ronald M.; Vavrinec, John; Zimmerman, Shon A.


    Draft annual report for the Cumulative Effects Study for the US Army Corps of Engineers, Portland District. This is the fifth annual report of a seven-year project (2004 through 2010) to evaluate the cumulative effects of habitat restoration actions in the 235-km-long Columbia River estuary. The project, called the Cumulative Effects Study, is being conducted for the U.S. Army Corps of Engineers, Portland District (CENWP), by the Marine Sciences Laboratory of the Pacific Northwest National Laboratory (PNNL), the Pt. Adams Biological Field Station of the National Marine Fisheries Service (NMFS), and the Columbia River Estuary Study Taskforce (CREST). The goal of the Cumulative Effects Study is to develop a methodology to evaluate the cumulative effects of multiple habitat restoration projects intended to benefit ecosystems supporting juvenile salmonids in the lower Columbia River and estuary (LCRE). Literature review in 2004 revealed no existing methods for such an evaluation and suggested that cumulative effects could be additive or synergistic. From 2005 through 2008, annual field research involved intensive, comparative studies paired by habitat type (tidal swamp versus marsh), trajectory (restoration versus reference site), and restoration action (tide gate versus culvert versus dike breach). During 2008, the specific objectives for the Cumulative Effects Study were to do the following: (1) Summarize the adaptive management framework for LCRE habitat restoration activities; (2) Finalize the levels-of-evidence approach and ecological theory underpinning the analysis, synthesis, and evaluation of the cumulative effects of multiple habitat restoration projects in the LCRE; (3) Summarize new results from analyses from 2005-2008 project research for the purpose of cumulative effects evaluation in the LCRE; (4) Initiate a synthesis and evaluation of cumulative effects in the LCRE; (5) Assess management implications, lessons learned, decision-making, 2009-2010 research

  15. Towards Trustable Digital Evidence with PKIDEV: PKI Based Digital Evidence Verification Model (United States)

    Uzunay, Yusuf; Incebacak, Davut; Bicakci, Kemal

    How to Capture and Preserve Digital Evidence Securely? For the investigation and prosecution of criminal activities that involve computers, digital evidence collected in the crime scene has a vital importance. On one side, it is a very challenging task for forensics professionals to collect them without any loss or damage. On the other, there is the second problem of providing the integrity and authenticity in order to achieve legal acceptance in a court of law. By conceiving digital evidence simply as one instance of digital data, it is evident that modern cryptography offers elegant solutions for this second problem. However, to our knowledge, there is not any previous work proposing a systematic model having a holistic view to address all the related security problems in this particular case of digital evidence verification. In this paper, we present PKIDEV (Public Key Infrastructure based Digital Evidence Verification model) as an integrated solution to provide security for the process of capturing and preserving digital evidence. PKIDEV employs, inter alia, cryptographic techniques like digital signatures and secure time-stamping as well as latest technologies such as GPS and EDGE. In our study, we also identify the problems public-key cryptography brings when it is applied to the verification of digital evidence.

  16. Structural Vibration Monitoring Using Cumulative Spectral Analysis

    Directory of Open Access Journals (Sweden)

    Satoru Goto


    Full Text Available This paper describes a resonance decay estimation for structural health monitoring in the presence of nonstationary vibrations. In structural health monitoring, the structure's frequency response and resonant decay characteristics are very important for understanding how the structure changes. Cumulative spectral analysis (CSA estimates the frequency decay by using the impulse response. However, measuring the impulse response of buildings is impractical due to the need to shake the building itself. In a previous study, we reported on system damping monitoring using cumulative harmonic analysis (CHA, which is based on CSA. The current study describes scale model experiments on estimating the hidden resonance decay under non-stationary noise conditions by using CSA for structural condition monitoring.

  17. The spectral-line moment-based (SLMB) modeling of the wide band and global blackbody-weighted transmission function and cumulative distribution function of the absorption coefficient in uniform gaseous media

    Energy Technology Data Exchange (ETDEWEB)

    Andre, Frederic [Centre de Thermique de Lyon (CETHIL, CNRS-INSA Lyon-UCBL), Bat. Sadi Carnot, INSA-Lyon, Lyon F-69621 (France)], E-mail:; Vaillon, Rodolphe [Centre de Thermique de Lyon (CETHIL, CNRS-INSA Lyon-UCBL), Bat. Sadi Carnot, INSA-Lyon, Lyon F-69621 (France)


    The spectral-line moment-based (SLMB) modeling is proposed for the calculation of radiative properties of gases on any spectral width. The associated mathematical formulation is obtained by applying several concepts of the k-distribution methods such as the reordering of the wavenumber scale by monotonic variations of the absorption coefficient, together with the application of the k-moment method's principles. This approach gives both a general formula for the BTF and a simple and readily applicable approximation for the blackbody-weighted cumulated k-distribution function of the absorption coefficient. The model is applied for the computation of wide band BTFs and cumulative k-distributions for uniform columns of CO{sub 2} and H{sub 2}O in the temperature range (300-2400 K) at atmospheric pressure. Model parameters are deduced from line-by-line (LBL) spectra calculated using the HITEMP database. Comparisons with LBL reference data as well as with contemporary modeling approaches (SLW, FSK, SNB) are performed and discussed.

  18. Flipped classroom model for learning evidence-based medicine. (United States)

    Rucker, Sydney Y; Ozdogan, Zulfukar; Al Achkar, Morhaf


    Journal club (JC), as a pedagogical strategy, has long been used in graduate medical education (GME). As evidence-based medicine (EBM) becomes a mainstay in GME, traditional models of JC present a number of insufficiencies and call for novel models of instruction. A flipped classroom model appears to be an ideal strategy to meet the demands to connect evidence to practice while creating engaged, culturally competent, and technologically literate physicians. In this article, we describe a novel model of flipped classroom in JC. We present the flow of learning activities during the online and face-to-face instruction, and then we highlight specific considerations for implementing a flipped classroom model. We show that implementing a flipped classroom model to teach EBM in a residency program not only is possible but also may constitute improved learning opportunity for residents. Follow-up work is needed to evaluate the effectiveness of this model on both learning and clinical practice.

  19. Cumulative effects of job characteristics on health. (United States)

    Fletcher, Jason M; Sindelar, Jody L; Yamaguchi, Shintaro


    We examine whether the job characteristics of physical demands and environmental conditions affect individual's health. Five-year cumulative measures of these job characteristics are used to reflect findings in the biological and physiological literature that indicate that cumulative exposure to hazards and stresses harms health. To create our analytic sample, we merge job characteristics from the Dictionary of Occupational Titles with the PSID data set. We control for early and also lagged health measures and a set of pre-determined characteristics to try to address concerns that individuals self-select into jobs. Our results indicate that individuals who work in jobs with the 'worst' conditions experience declines in their health, though this effect varies by demographic group. We also find some evidence that job characteristics are more detrimental to the health of females and older workers. Finally, we report suggestive evidence that earned income, a job characteristic, partially cushions the health impact of physical demands and harsh environmental conditions for workers. These results are robust to inclusion of occupation fixed effects. Copyright © 2010 John Wiley & Sons, Ltd.

  20. Constructing Scientific Arguments Using Evidence from Dynamic Computational Climate Models (United States)

    Pallant, Amy; Lee, Hee-Sun


    Modeling and argumentation are two important scientific practices students need to develop throughout school years. In this paper, we investigated how middle and high school students ( N = 512) construct a scientific argument based on evidence from computational models with which they simulated climate change. We designed scientific argumentation tasks with three increasingly complex dynamic climate models. Each scientific argumentation task consisted of four parts: multiple-choice claim, openended explanation, five-point Likert scale uncertainty rating, and open-ended uncertainty rationale. We coded 1,294 scientific arguments in terms of a claim's consistency with current scientific consensus, whether explanations were model based or knowledge based and categorized the sources of uncertainty (personal vs. scientific). We used chi-square and ANOVA tests to identify significant patterns. Results indicate that (1) a majority of students incorporated models as evidence to support their claims, (2) most students used model output results shown on graphs to confirm their claim rather than to explain simulated molecular processes, (3) students' dependence on model results and their uncertainty rating diminished as the dynamic climate models became more and more complex, (4) some students' misconceptions interfered with observing and interpreting model results or simulated processes, and (5) students' uncertainty sources reflected more frequently on their assessment of personal knowledge or abilities related to the tasks than on their critical examination of scientific evidence resulting from models. These findings have implications for teaching and research related to the integration of scientific argumentation and modeling practices to address complex Earth systems.

  1. Higher order cumulants in colorless partonic plasma

    Energy Technology Data Exchange (ETDEWEB)

    Cherif, S. [Sciences and Technologies Department, University of Ghardaia, Ghardaia, Algiers (Algeria); Laboratoire de Physique et de Mathématiques Appliquées (LPMA), ENS-Kouba (Bachir El-Ibrahimi), Algiers (Algeria); Ahmed, M. A. A. [Department of Physics, College of Science, Taibah University Al-Madinah Al-Mounawwarah KSA (Saudi Arabia); Department of Physics, Taiz University in Turba, Taiz (Yemen); Laboratoire de Physique et de Mathématiques Appliquées (LPMA), ENS-Kouba (Bachir El-Ibrahimi), Algiers (Algeria); Ladrem, M., E-mail: [Department of Physics, College of Science, Taibah University Al-Madinah Al-Mounawwarah KSA (Saudi Arabia); Laboratoire de Physique et de Mathématiques Appliquées (LPMA), ENS-Kouba (Bachir El-Ibrahimi), Algiers (Algeria)


    Any physical system considered to study the QCD deconfinement phase transition certainly has a finite volume, so the finite size effects are inevitably present. This renders the location of the phase transition and the determination of its order as an extremely difficult task, even in the simplest known cases. In order to identify and locate the colorless QCD deconfinement transition point in finite volume T{sub 0}(V), a new approach based on the finite-size cumulant expansion of the order parameter and the ℒ{sub m,n}-Method is used. We have shown that both cumulants of higher order and their ratios, associated to the thermodynamical fluctuations of the order parameter, in QCD deconfinement phase transition behave in a particular enough way revealing pronounced oscillations in the transition region. The sign structure and the oscillatory behavior of these in the vicinity of the deconfinement phase transition point might be a sensitive probe and may allow one to elucidate their relation to the QCD phase transition point. In the context of our model, we have shown that the finite volume transition point is always associated to the appearance of a particular point in whole higher order cumulants under consideration.

  2. Expansive Soil Crack Depth under Cumulative Damage

    Directory of Open Access Journals (Sweden)

    Bei-xiao Shi


    Full Text Available The crack developing depth is a key problem to slope stability of the expansive soil and its project governance and the crack appears under the roles of dry-wet cycle and gradually develops. It is believed from the analysis that, because of its own cohesion, the expansive soil will have a certain amount of deformation under pulling stress but without cracks. The soil body will crack only when the deformation exceeds the ultimate tensile strain that causes cracks. And it is also believed that, due to the combined effect of various environmental factors, particularly changes of the internal water content, the inherent basic physical properties of expansive soil are weakened, and irreversible cumulative damages are eventually formed, resulting in the development of expansive soil cracks in depth. Starting from the perspective of volumetric strain that is caused by water loss, considering the influences of water loss rate and dry-wet cycle on crack developing depth, the crack developing depth calculation model which considers the water loss rate and the cumulative damages is established. Both the proposal of water loss rate and the application of cumulative damage theory to the expansive soil crack development problems try to avoid difficulties in matrix suction measurement, which will surely play a good role in promoting and improving the research of unsaturated expansive soil.

  3. Higher order cumulants in colorless partonic plasma

    International Nuclear Information System (INIS)

    Cherif, S.; Ahmed, M. A. A.; Ladrem, M.


    Any physical system considered to study the QCD deconfinement phase transition certainly has a finite volume, so the finite size effects are inevitably present. This renders the location of the phase transition and the determination of its order as an extremely difficult task, even in the simplest known cases. In order to identify and locate the colorless QCD deconfinement transition point in finite volume T 0 (V), a new approach based on the finite-size cumulant expansion of the order parameter and the ℒ m,n -Method is used. We have shown that both cumulants of higher order and their ratios, associated to the thermodynamical fluctuations of the order parameter, in QCD deconfinement phase transition behave in a particular enough way revealing pronounced oscillations in the transition region. The sign structure and the oscillatory behavior of these in the vicinity of the deconfinement phase transition point might be a sensitive probe and may allow one to elucidate their relation to the QCD phase transition point. In the context of our model, we have shown that the finite volume transition point is always associated to the appearance of a particular point in whole higher order cumulants under consideration.

  4. Comparison of evidence theory and Bayesian theory for uncertainty modeling

    International Nuclear Information System (INIS)

    Soundappan, Prabhu; Nikolaidis, Efstratios; Haftka, Raphael T.; Grandhi, Ramana; Canfield, Robert


    This paper compares Evidence Theory (ET) and Bayesian Theory (BT) for uncertainty modeling and decision under uncertainty, when the evidence about uncertainty is imprecise. The basic concepts of ET and BT are introduced and the ways these theories model uncertainties, propagate them through systems and assess the safety of these systems are presented. ET and BT approaches are demonstrated and compared on challenge problems involving an algebraic function whose input variables are uncertain. The evidence about the input variables consists of intervals provided by experts. It is recommended that a decision-maker compute both the Bayesian probabilities of the outcomes of alternative actions and their plausibility and belief measures when evidence about uncertainty is imprecise, because this helps assess the importance of imprecision and the value of additional information. Finally, the paper presents and demonstrates a method for testing approaches for decision under uncertainty in terms of their effectiveness in making decisions

  5. Electro-cumulation CNF project

    CERN Document Server

    Grishin, V G


    bound or free ion current within solid substances; non-plain symmetry; cumulation of the ion interaction. Experimental result: an Ice SuperPolarization. Cold nuclear fusion ? At . Keywords: ion, current, solid, symmetry, cumulation, cold nuclear fusion, polarization, depolarization, ionic conductor, superionic conductor, ice, crystal, strain, V-center, V-centre, doped crystal, interstitial impurity, intrinsic color center, high pressure technology, Bridgman, experiment, crowdion, dielectric, proton, layer, defect, lattice, dynamics, electromigration, mobility, muon catalysis, concentration, doping, dopant, conductivity, pycnonuclear reaction, permittivity, dielectric constant, point defects, interstitials, polarizability, imperfection, defect centers, glass, epitaxy, sodium hydroxide, metallic substrate, crystallization, point, tip, susceptibility, ferroelectric, ordering, force, correlation, collective, shift, distortion, coalescence, crowdions, electrolysis.

  6. Cumulants in perturbation expansions for non-equilibrium field theory

    International Nuclear Information System (INIS)

    Fauser, R.


    The formulation of perturbation expansions for a quantum field theory of strongly interacting systems in a general non-equilibrium state is discussed. Non-vanishing initial correlations are included in the formulation of the perturbation expansion in terms of cumulants. The cumulants are shown to be the suitable candidate for summing up the perturbation expansion. Also a linked-cluster theorem for the perturbation series with cumulants is presented. Finally a generating functional of the perturbation series with initial correlations is studied. We apply the methods to a simple model of a fermion-boson system. (orig.)

  7. Cumulative exposure to poor housing affordability and its association with mental health in men and women. (United States)

    Bentley, Rebecca; Baker, Emma; Mason, Kate


    Poor housing affordability affects around 10% of the Australian population and is increasingly prevalent. The authors tested two hypotheses: that cumulative exposure to housing affordability stress (HAS) is associated with poorer mental health and that effects vary by gender. The authors estimated the relationship between cumulative exposure to HAS and mental health among 15478 participants in an Australian longitudinal survey between 2001 and 2009. Individuals were classified as being in HAS if household income was in the lowest 40% of the national distribution and housing costs exceeded 30% of income. Exposure to HAS ranged from 1 to 8 annual waves. Mental health was measured using the Short Form 36 Mental Component Summary (MCS) score. To test the extent to which any observed associations were explained by compositional factors, random- and fixed-effects models were estimated. In the random-effects models, mental health scores decreased with increasing cumulative exposure to HAS (up until 4+ years). This relationship differed by gender, with a stronger dose-response observed among men. The mean MCS score of men experiencing four to eight waves of housing stress was 2.02 points lower than men not in HAS (95% CI -3.89 to -0.16). In the fixed-effects models, there was no evidence of a cumulative effect of HAS on mental health; however, lower MCS was observed after a single year in HAS (β=-0.70, 95% CI -1.02 to -0.37). While average mental health was lower for individuals with longer exposure to HAS, the mental health effect appears to be due to compositional factors. Furthermore, men and women appear to experience cumulative HAS differently.

  8. Bridging Research, Practice, and Policy: The "Evidence Academy" Conference Model. (United States)

    Rohweder, Catherine L; Laping, Jane L; Diehl, Sandra J; Moore, Alexis A; Isler, Malika Roman; Scott, Jennifer Elissa; Enga, Zoe Kaori; Black, Molly C; Dave, Gaurav; Corbie-Smith, Giselle; Melvin, Cathy L


    Innovative models to facilitate more rapid uptake of research findings into practice are urgently needed. Community members who engage in research can accelerate this process by acting as adoption agents. We implemented an Evidence Academy conference model bringing together researchers, health care professionals, advocates, and policy makers across North Carolina to discuss high-impact, life-saving study results. The overall goal is to develop dissemination and implementation strategies for translating evidence into practice and policy. Each 1-day, single-theme, regional meeting focuses on a leading community-identified health priority. The model capitalizes on the power of diverse local networks to encourage broad, common awareness of new research findings. Furthermore, it emphasizes critical reflection and active group discussion on how to incorporate new evidence within and across organizations, health care systems, and communities. During the concluding session, participants are asked to articulate action plans relevant to their individual interests, work setting, or area of expertise.

  9. Cumulative Paired φ-Entropy

    Directory of Open Access Journals (Sweden)

    Ingo Klein


    Full Text Available A new kind of entropy will be introduced which generalizes both the differential entropy and the cumulative (residual entropy. The generalization is twofold. First, we simultaneously define the entropy for cumulative distribution functions (cdfs and survivor functions (sfs, instead of defining it separately for densities, cdfs, or sfs. Secondly, we consider a general “entropy generating function” φ, the same way Burbea et al. (IEEE Trans. Inf. Theory 1982, 28, 489–495 and Liese et al. (Convex Statistical Distances; Teubner-Verlag, 1987 did in the context of φ-divergences. Combining the ideas of φ-entropy and cumulative entropy leads to the new “cumulative paired φ-entropy” ( C P E φ . This new entropy has already been discussed in at least four scientific disciplines, be it with certain modifications or simplifications. In the fuzzy set theory, for example, cumulative paired φ-entropies were defined for membership functions, whereas in uncertainty and reliability theories some variations of C P E φ were recently considered as measures of information. With a single exception, the discussions in the scientific disciplines appear to be held independently of each other. We consider C P E φ for continuous cdfs and show that C P E φ is rather a measure of dispersion than a measure of information. In the first place, this will be demonstrated by deriving an upper bound which is determined by the standard deviation and by solving the maximum entropy problem under the restriction of a fixed variance. Next, this paper specifically shows that C P E φ satisfies the axioms of a dispersion measure. The corresponding dispersion functional can easily be estimated by an L-estimator, containing all its known asymptotic properties. C P E φ is the basis for several related concepts like mutual φ-information, φ-correlation, and φ-regression, which generalize Gini correlation and Gini regression. In addition, linear rank tests for scale that

  10. AIC, BIC, Bayesian evidence against the interacting dark energy model

    International Nuclear Information System (INIS)

    Szydlowski, Marek; Krawiec, Adam; Kurek, Aleksandra; Kamionka, Michal


    Recent astronomical observations have indicated that the Universe is in a phase of accelerated expansion. While there are many cosmological models which try to explain this phenomenon, we focus on the interacting ΛCDM model where an interaction between the dark energy and dark matter sectors takes place. This model is compared to its simpler alternative - the ΛCDM model. To choose between these models the likelihood ratio test was applied as well as the model comparison methods (employing Occam's principle): the Akaike information criterion (AIC), the Bayesian information criterion (BIC) and the Bayesian evidence. Using the current astronomical data: type Ia supernova (Union2.1), h(z), baryon acoustic oscillation, the Alcock- Paczynski test, and the cosmic microwave background data, we evaluated both models. The analyses based on the AIC indicated that there is less support for the interacting ΛCDM model when compared to the ΛCDM model, while those based on the BIC indicated that there is strong evidence against it in favor of the ΛCDM model. Given the weak or almost non-existing support for the interacting ΛCDM model and bearing in mind Occam's razor we are inclined to reject this model. (orig.)

  11. Characterization of pore volume of cumulative water injection distribution

    Directory of Open Access Journals (Sweden)

    Guoqing Feng


    Full Text Available Pore volume of Cumulative water injection is one of the factors for evaluating water flood effect in a water flood oil field. In previous study, there were limited lab studies for evaluating oil displacement efficiency. A method to characterize the distribution of pore volume of cumulative water injection is proposed in this paper, and it is verified by a five-spot water flooding streamline simulation model. The logarithmic relation between pore volume of cumulative water injection and water saturation is established by regression. An inflection point and limit point of cumulative water injection pore volume are identified. Current simulation model indicates inflection point appears after 2–5 pore volume (PV injection, and limit point appears after 15–25 PV injection. Both inflection and limit point vary in different regions of reservoir.

  12. Evaluation of Cumulative Ecosystem Response to Restoration Projects in the Lower Columbia River and Estuary, 2010

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Gary E.; Diefenderfer, Heida L.; Thom, Ronald M.; Roegner, G. Curtis; Ebberts, Blaine D.; Skalski, John R.; Borde, Amy B.; Dawley, Earl; Coleman, Andre M.; Woodruff, Dana L.; Breithaupt, Stephen A.; Cameron, April; Corbett, C.; Donley, Erin E.; Jay, D. A.; Ke, Yinghai; Leffler, K.; McNeil, C.; Studebaker, Cindy; Tagestad, Jerry D.


    This is the seventh and final annual report of a project (2004–2010) addressing evaluation of the cumulative effects of habitat restoration actions in the 235-km-long lower Columbia River and estuary. The project, called the Cumulative Effects (CE) study, was conducted for the U.S. Army Corps of Engineers Portland District by a collaboration of research agencies led by the Pacific Northwest National Laboratory. We achieved the primary goal of the CE study to develop a methodology to evaluate the cumulative effects of habitat actions in the Columbia Estuary Ecosystem Restoration Program. We delivered 1) standard monitoring protocols and methods to prioritize monitoring activities; 2) the theoretical and empirical basis for a CE methodology using levels-of-evidence; 3) evaluations of cumulative effects using ecological relationships, geo-referenced data, hydrodynamic modeling, and meta-analyses; and 4) an adaptive management process to coordinate and coalesce restoration efforts in the LCRE. A solid foundation has been laid for future comprehensive evaluations of progress made by the Columbia Estuary Ecosystem Restoration Program to understand, conserve, and restore ecosystems in the lower Columbia River and estuary.

  13. Some Characterization Results on Dynamic Cumulative Residual Tsallis Entropy

    Directory of Open Access Journals (Sweden)

    Madan Mohan Sati


    Full Text Available We propose a generalized cumulative residual information measure based on Tsallis entropy and its dynamic version. We study the characterizations of the proposed information measure and define new classes of life distributions based on this measure. Some applications are provided in relation to weighted and equilibrium probability models. Finally the empirical cumulative Tsallis entropy is proposed to estimate the new information measure.

  14. Steps and pips in the history of the cumulative recorder.


    Lattal, Kennon A


    From its inception in the 1930s until very recent times, the cumulative recorder was the most widely used measurement instrument in the experimental analysis of behavior. It was an essential instrument in the discovery and analysis of schedules of reinforcement, providing the first real-time analysis of operant response rates and patterns. This review traces the evolution of the cumulative recorder from Skinner's early modified kymographs through various models developed by Skinner and his co...

  15. Flipped classroom model for learning evidence-based medicine

    Directory of Open Access Journals (Sweden)

    Rucker SY


    Full Text Available Sydney Y Rucker,1 Zulfukar Ozdogan,1 Morhaf Al Achkar2 1School of Education, Indiana University, Bloomington, IN, 2Department of Family Medicine, School of Medicine, University of Washington, Seattle, WA, USA Abstract: Journal club (JC, as a pedagogical strategy, has long been used in graduate medical education (GME. As evidence-based medicine (EBM becomes a mainstay in GME, traditional models of JC present a number of insufficiencies and call for novel models of instruction. A flipped classroom model appears to be an ideal strategy to meet the demands to connect evidence to practice while creating engaged, culturally competent, and technologically literate physicians. In this article, we describe a novel model of flipped classroom in JC. We present the flow of learning activities during the online and face-to-face instruction, and then we highlight specific considerations for implementing a flipped classroom model. We show that implementing a flipped classroom model to teach EBM in a residency program not only is possible but also may constitute improved learning opportunity for residents. Follow-up work is needed to evaluate the effectiveness of this model on both learning and clinical practice. Keywords: evidence-based medicine, flipped classroom, residency education

  16. Evidence accumulation as a model for lexical selection. (United States)

    Anders, R; Riès, S; van Maanen, L; Alario, F X


    We propose and demonstrate evidence accumulation as a plausible theoretical and/or empirical model for the lexical selection process of lexical retrieval. A number of current psycholinguistic theories consider lexical selection as a process related to selecting a lexical target from a number of alternatives, which each have varying activations (or signal supports), that are largely resultant of an initial stimulus recognition. We thoroughly present a case for how such a process may be theoretically explained by the evidence accumulation paradigm, and we demonstrate how this paradigm can be directly related or combined with conventional psycholinguistic theory and their simulatory instantiations (generally, neural network models). Then with a demonstrative application on a large new real data set, we establish how the empirical evidence accumulation approach is able to provide parameter results that are informative to leading psycholinguistic theory, and that motivate future theoretical development. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Evidence and Formal Models in the Linguistic Sciences (United States)

    Santana, Carlos Gray


    This dissertation contains a collection of essays centered on the relationship between theoretical model-building and empirical evidence-gathering in linguistics and related language sciences. The first chapter sets the stage by demonstrating that the subject matter of linguistics is manifold, and contending that discussion of relationships…

  18. Compositional models and conditional independence in evidence theory

    Czech Academy of Sciences Publication Activity Database

    Jiroušek, Radim; Vejnarová, Jiřina


    Roč. 52, č. 3 (2011), s. 316-334 ISSN 0888-613X Institutional research plan: CEZ:AV0Z10750506 Keywords : Evidence theory * Conditional independence * multidimensional models Subject RIV: BA - General Mathematics Impact factor: 1.948, year: 2011

  19. The Algebra of the Cumulative Percent Operation. (United States)

    Berry, Andrew J.


    Discusses how to help students avoid some pervasive reasoning errors in solving cumulative percent problems. Discusses the meaning of ."%+b%." the additive inverse of ."%." and other useful applications. Emphasizes the operational aspect of the cumulative percent concept. (KHR)

  20. Adaptive strategies for cumulative cultural learning. (United States)

    Ehn, Micael; Laland, Kevin


    The demographic and ecological success of our species is frequently attributed to our capacity for cumulative culture. However, it is not yet known how humans combine social and asocial learning to generate effective strategies for learning in a cumulative cultural context. Here we explore how cumulative culture influences the relative merits of various pure and conditional learning strategies, including pure asocial and social learning, critical social learning, conditional social learning and individual refiner strategies. We replicate the Rogers' paradox in the cumulative setting. However, our analysis suggests that strategies that resolved Rogers' paradox in a non-cumulative setting may not necessarily evolve in a cumulative setting, thus different strategies will optimize cumulative and non-cumulative cultural learning. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Cognitive Attachment Model of Voices: Evidence Base and Future Implications. (United States)

    Berry, Katherine; Varese, Filippo; Bucci, Sandra


    There is a robust association between hearing voices and exposure to traumatic events. Identifying mediating mechanisms for this relationship is key to theories of voice hearing and the development of therapies for distressing voices. This paper outlines the Cognitive Attachment model of Voices (CAV), a theoretical model to understand the relationship between earlier interpersonal trauma and distressing voice hearing. The model builds on attachment theory and well-established cognitive models of voices and argues that attachment and dissociative processes are key psychological mechanisms that explain how trauma influences voice hearing. Following the presentation of the model, the paper will review the current state of evidence regarding the proposed mechanisms of vulnerability to voice hearing and maintenance of voice-related distress. This review will include evidence from studies supporting associations between dissociation and voices, followed by details of our own research supporting the role of dissociation in mediating the relationship between trauma and voices and evidence supporting the role of adult attachment in influencing beliefs and relationships that voice hearers can develop with voices. The paper concludes by outlining the key questions that future research needs to address to fully test the model and the clinical implications that arise from the work.


    A physiologically-based pharmacokinetic (PBPK) model for a mixture of N-methyl carbamate pesticides was developed based on single chemical models. The model was used to compare urinary metabolite concentrations to levels from National Health and Nutrition Examination Survey (NHA...

  3. Completing the Remedial Sequence and College-Level Credit-Bearing Math: Comparing Binary, Cumulative, and Continuation Ratio Logistic Regression Models (United States)

    Davidson, J. Cody


    Mathematics is the most common subject area of remedial need and the majority of remedial math students never pass a college-level credit-bearing math class. The majorities of studies that investigate this phenomenon are conducted at community colleges and use some type of regression model; however, none have used a continuation ratio model. The…

  4. Cumulative risk effects in the bullying of children and young people with autism spectrum conditions. (United States)

    Hebron, Judith; Oldfield, Jeremy; Humphrey, Neil


    Students with autism are more likely to be bullied than their typically developing peers. However, several studies have shown that their likelihood of being bullied increases in the context of exposure to certain risk factors (e.g. behaviour difficulties and poor peer relationships). This study explores vulnerability to bullying from a cumulative risk perspective, where the number of risks rather than their nature is considered. A total of 722 teachers and 119 parents of young people with autism spectrum conditions participated in the study. Established risk factors were summed to form a cumulative risk score in teacher and parent models. There was evidence of a cumulative risk effect in both models, suggesting that as the number of risks increased, so did exposure to bullying. A quadratic effect was found in the teacher model, indicating that there was a disproportionate increase in the likelihood of being bullied in relation to the number of risk factors to which a young person was exposed. In light of these findings, it is proposed that more attention needs to be given to the number of risks to which children and young people with autism spectrum conditions are exposed when planning interventions and providing a suitable educational environment.

  5. Evident?

    DEFF Research Database (Denmark)

    Plant, Peter


    Quality assurance and evidence in career guidance in Europe are often seen as self-evident approaches, but particular interests lie behind......Quality assurance and evidence in career guidance in Europe are often seen as self-evident approaches, but particular interests lie behind...

  6. No Evidence for Extensions to the Standard Cosmological Model (United States)

    Heavens, Alan; Fantaye, Yabebal; Sellentin, Elena; Eggers, Hans; Hosenie, Zafiirah; Kroon, Steve; Mootoovaloo, Arrykrishna


    We compute the Bayesian evidence for models considered in the main analysis of Planck cosmic microwave background data. By utilizing carefully defined nearest-neighbor distances in parameter space, we reuse the Monte Carlo Markov chains already produced for parameter inference to compute Bayes factors B for many different model-data set combinations. The standard 6-parameter flat cold dark matter model with a cosmological constant (Λ CDM ) is favored over all other models considered, with curvature being mildly favored only when cosmic microwave background lensing is not included. Many alternative models are strongly disfavored by the data, including primordial correlated isocurvature models (ln B =-7.8 ), nonzero scalar-to-tensor ratio (ln B =-4.3 ), running of the spectral index (ln B =-4.7 ), curvature (ln B =-3.6 ), nonstandard numbers of neutrinos (ln B =-3.1 ), nonstandard neutrino masses (ln B =-3.2 ), nonstandard lensing potential (ln B =-4.6 ), evolving dark energy (ln B =-3.2 ), sterile neutrinos (ln B =-6.9 ), and extra sterile neutrinos with a nonzero scalar-to-tensor ratio (ln B =-10.8 ). Other models are less strongly disfavored with respect to flat Λ CDM . As with all analyses based on Bayesian evidence, the final numbers depend on the widths of the parameter priors. We adopt the priors used in the Planck analysis, while performing a prior sensitivity analysis. Our quantitative conclusion is that extensions beyond the standard cosmological model are disfavored by Planck data. Only when newer Hubble constant measurements are included does Λ CDM become disfavored, and only mildly, compared with a dynamical dark energy model (ln B ˜+2 ).

  7. Evidence-based models of care for people with epilepsy.

    LENUS (Irish Health Repository)

    Fitzsimons, Mary


    Advances in medical science and technology, together with improved medical and nursing care, are continuously improving health outcomes in chronic illness, including epilepsy. The consequent increasing diagnostic and therapeutic complexity is placing a burgeoning strain on health care systems. In response, an international move to transform chronic disease management (CDM) aims to optimize the quality and safety of care while containing health care costs. CDM models recommend: integration of care across organizational boundaries that is supported with information and communication technology; patient self-management; and guideline implementation to promote standardized care. Evidence of the effectiveness of CDM models in epilepsy care is presented in this review article.

  8. Business models of micro businesses: Empirical evidence from creative industries

    Directory of Open Access Journals (Sweden)

    Pfeifer Sanja


    Full Text Available Business model describes how a business identifies and creates value for customers and how it organizes itself to capture some of this value in a profitable manner. Previous studies of business models in creative industries have only recently identified the unresolved issues in this field of research. The main objective of this article is to analyse the structure and diversity of business models and to deduce how these components interact or change in the context of micro and small businesses in creative services such as advertising, architecture and design. The article uses a qualitative approach. Case studies and semi-structured, in-depth interviews with six owners/managers of micro businesses in Croatia provide rich data. Structural coding in data analysis has been performed manually. The qualitative analysis has indicative relevance for the assessment and comparison of business models, however, it provides insights into which components of business models seem to be consolidated and which seem to contribute to the diversity of business models in creative industries. The article contributes to the advancement of empirical evidence and conceptual constructs that might lead to more advanced methodological approaches and proposition of the core typologies or classifications of business models in creative industries. In addition, a more detailed mapping of different choices available in managing value creation, value capturing or value networking might be a valuable help for owners/managers who want to change or cross-fertilize their business models.

  9. Models of maternity care: evidence for midwifery continuity of care. (United States)

    Homer, Caroline Se


    There has been substantial reform in the past decade in the provision of maternal and child health services, and specifically regarding models of maternity care. Increasingly, midwives are working together in small groups to provide midwife-led continuity of care. This article reviews the current evidence for models of maternity care that provide midwifery continuity of care, in terms of their impact on clinical outcomes, the views of midwives and childbearing women, and health service costs. A systematic review of midwife-led continuity of care models identified benefits for women and babies, with no adverse effects. Non-randomised studies have shown benefits of midwifery continuity of care for specific groups, such as Aboriginal and Torres Strait Islander women. There are also benefits for midwives, including high levels of job satisfaction and less occupational burnout. Implementing midwifery continuity of care in public and private settings in Australia has been challenging, despite the evidence in its favour and government policy documents that support it. A reorganisation of the way maternity services are provided in Australia is required to ensure that women across the country can access this model of care. Critical to such reform is collaboration with obstetricians, general practitioners, paediatricians and other medical professionals involved in the care of pregnant women, as well as professional respect for the central role of midwives in the provision of maternity care. More research is needed into ways to ensure that all childbearing women can access midwifery continuity of care.

  10. Session: What do we know about cumulative or population impacts

    Energy Technology Data Exchange (ETDEWEB)

    Kerlinger, Paul; Manville, Al; Kendall, Bill


    This session at the Wind Energy and Birds/Bats workshop consisted of a panel discussion followed by a discussion/question and answer period. The panelists were Paul Kerlinger, Curry and Kerlinger, LLC, Al Manville, U.S. Fish and Wildlife Service, and Bill Kendall, US Geological Service. The panel addressed the potential cumulative impacts of wind turbines on bird and bat populations over time. Panel members gave brief presentations that touched on what is currently known, what laws apply, and the usefulness of population modeling. Topics addressed included which sources of modeling should be included in cumulative impacts, comparison of impacts from different modes of energy generation, as well as what research is still needed regarding cumulative impacts of wind energy development on bird and bat populations.

  11. Likelihood ratio model for classification of forensic evidence

    Energy Technology Data Exchange (ETDEWEB)

    Zadora, G., E-mail: [Institute of Forensic Research, Westerplatte 9, 31-033 Krakow (Poland); Neocleous, T., E-mail: [University of Glasgow, Department of Statistics, 15 University Gardens, Glasgow G12 8QW (United Kingdom)


    One of the problems of analysis of forensic evidence such as glass fragments, is the determination of their use-type category, e.g. does a glass fragment originate from an unknown window or container? Very small glass fragments arise during various accidents and criminal offences, and could be carried on the clothes, shoes and hair of participants. It is therefore necessary to obtain information on their physicochemical composition in order to solve the classification problem. Scanning Electron Microscopy coupled with an Energy Dispersive X-ray Spectrometer and the Glass Refractive Index Measurement method are routinely used in many forensic institutes for the investigation of glass. A natural form of glass evidence evaluation for forensic purposes is the likelihood ratio-LR = p(E|H{sub 1})/p(E|H{sub 2}). The main aim of this paper was to study the performance of LR models for glass object classification which considered one or two sources of data variability, i.e. between-glass-object variability and(or) within-glass-object variability. Within the proposed model a multivariate kernel density approach was adopted for modelling the between-object distribution and a multivariate normal distribution was adopted for modelling within-object distributions. Moreover, a graphical method of estimating the dependence structure was employed to reduce the highly multivariate problem to several lower-dimensional problems. The performed analysis showed that the best likelihood model was the one which allows to include information about between and within-object variability, and with variables derived from elemental compositions measured by SEM-EDX, and refractive values determined before (RI{sub b}) and after (RI{sub a}) the annealing process, in the form of dRI = log{sub 10}|RI{sub a} - RI{sub b}|. This model gave better results than the model with only between-object variability considered. In addition, when dRI and variables derived from elemental compositions were used, this

  12. Likelihood ratio model for classification of forensic evidence

    International Nuclear Information System (INIS)

    Zadora, G.; Neocleous, T.


    One of the problems of analysis of forensic evidence such as glass fragments, is the determination of their use-type category, e.g. does a glass fragment originate from an unknown window or container? Very small glass fragments arise during various accidents and criminal offences, and could be carried on the clothes, shoes and hair of participants. It is therefore necessary to obtain information on their physicochemical composition in order to solve the classification problem. Scanning Electron Microscopy coupled with an Energy Dispersive X-ray Spectrometer and the Glass Refractive Index Measurement method are routinely used in many forensic institutes for the investigation of glass. A natural form of glass evidence evaluation for forensic purposes is the likelihood ratio-LR = p(E|H 1 )/p(E|H 2 ). The main aim of this paper was to study the performance of LR models for glass object classification which considered one or two sources of data variability, i.e. between-glass-object variability and(or) within-glass-object variability. Within the proposed model a multivariate kernel density approach was adopted for modelling the between-object distribution and a multivariate normal distribution was adopted for modelling within-object distributions. Moreover, a graphical method of estimating the dependence structure was employed to reduce the highly multivariate problem to several lower-dimensional problems. The performed analysis showed that the best likelihood model was the one which allows to include information about between and within-object variability, and with variables derived from elemental compositions measured by SEM-EDX, and refractive values determined before (RI b ) and after (RI a ) the annealing process, in the form of dRI = log 10 |RI a - RI b |. This model gave better results than the model with only between-object variability considered. In addition, when dRI and variables derived from elemental compositions were used, this model outperformed two other

  13. A Photographic View of Cumulative Distribution Functions (United States)

    Jernigan, Robert W.


    This article shows a concrete and easy recognizable view of a cumulative distribution function(cdf). Photograph views of the search tabs on dictionaries are used to increase students' understanding and facility with the concept of a cumulative distribution function. Projects for student investigations are also given. This motivation and view helps…

  14. Cumulative Student Loan Debt in Minnesota, 2015 (United States)

    Williams-Wyche, Shaun


    To better understand student debt in Minnesota, the Minnesota Office of Higher Education (the Office) gathers information on cumulative student loan debt from Minnesota degree-granting institutions. These data detail the number of students with loans by institution, the cumulative student loan debt incurred at that institution, and the percentage…

  15. System-Reliability Cumulative-Binomial Program (United States)

    Scheuer, Ernest M.; Bowerman, Paul N.


    Cumulative-binomial computer program, NEWTONP, one of set of three programs, calculates cumulative binomial probability distributions for arbitrary inputs. NEWTONP, CUMBIN (NPO-17555), and CROSSER (NPO-17557), used independently of one another. Program finds probability required to yield given system reliability. Used by statisticians and users of statistical procedures, test planners, designers, and numerical analysts. Program written in C.

  16. Common-Reliability Cumulative-Binomial Program (United States)

    Scheuer, Ernest, M.; Bowerman, Paul N.


    Cumulative-binomial computer program, CROSSER, one of set of three programs, calculates cumulative binomial probability distributions for arbitrary inputs. CROSSER, CUMBIN (NPO-17555), and NEWTONP (NPO-17556), used independently of one another. Point of equality between reliability of system and common reliability of components found. Used by statisticians and users of statistical procedures, test planners, designers, and numerical analysts. Program written in C.

  17. Cumulative human impacts on marine predators

    DEFF Research Database (Denmark)

    Maxwell, Sara M; Hazen, Elliott L; Bograd, Steven J


    Stressors associated with human activities interact in complex ways to affect marine ecosystems, yet we lack spatially explicit assessments of cumulative impacts on ecologically and economically key components such as marine predators. Here we develop a metric of cumulative utilization and impact...

  18. Development of cumulative distribution functions for dry bulb ...

    African Journals Online (AJOL)

    The probability density function (PDF) and cumulative distribution function (CDF) for eighteen locations in Nigeria were computed from long term hourly dry bulb temperature obtained from Nigerian Meteorological Services Agency, Oshodi, Nigeria for 1994-2008 or 1995-2009. Mathematical models were developed from the ...

  19. Cumulative Damage Modelling in Composite Laminates (United States)


    used dental ’ ( orthodontal ) wires . In this program the high strength and % % deformation characteristics of several types of dental wires are "k...determined before and after the wires are subjected to five 0 8 different procedures for sterilization. The laboratory equipment used in this study includes

  20. Cumulative Damage Model for Advanced Composite Materials. (United States)


    SECURITY CLASSIFICATION OF THIS PAGE (When Data Entered) Unclassified SIRCURITY CLASSIFICATION OF THIS PAOU( Ilha . Data Ent~E) . 20. (-Continued) ci...with no enclosure surrounding the specimen. In the elevated temperature tests, the specimens were heated by wrapping aluminum foil around the specimen...and then winding electrical resistance heating tape on top of the aluminum. A VARIAC transformer vas used to regulate the heat provided * to the

  1. Cumulative hip contact stress predicts osteoarthritis in DDH. (United States)

    Mavcic, Blaz; Iglic, Ales; Kralj-Iglic, Veronika; Brand, Richard A; Vengust, Rok


    Hip stresses are generally believed to influence whether a hip develops osteoarthritis (OA); similarly, various osteotomies have been proposed to reduce contact stresses and the risk of OA. We asked whether elevated hip contact stress predicted osteoarthritis in initially asymptomatic human hips. We identified 58 nonoperatively treated nonsubluxated hips with developmental dysplasia (DDH) without symptoms at skeletal maturity; the control group included 48 adult hips without hip disease. The minimum followup was 20 years (mean, 29 years; range, 20-41 years). Peak contact stress was computed with the HIPSTRESS method using anteroposterior pelvic radiographs at skeletal maturity. The cumulative contact stress was determined by multiplying the peak contact stress by age at followup. We compared WOMAC scores and radiographic indices of OA. Dysplastic hips had higher mean peak contact and higher mean cumulative contact stress than normal hips. Mean WOMAC scores and percentage of asymptomatic hips in the study group (mean age 51 years) were similar to those in the control group (mean age 68 years). After adjusting for gender and age, the cumulative contact stress, Wiberg center-edge angle, body mass index, but not the peak contact stress, independently predicted the final WOMAC score in dysplastic hips but not in normal hips. Cumulative contact stress predicted early hip OA better than the Wiberg center-edge angle. Level II, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.

  2. Hyperscaling breakdown and Ising spin glasses: The Binder cumulant (United States)

    Lundow, P. H.; Campbell, I. A.


    Among the Renormalization Group Theory scaling rules relating critical exponents, there are hyperscaling rules involving the dimension of the system. It is well known that in Ising models hyperscaling breaks down above the upper critical dimension. It was shown by Schwartz (1991) that the standard Josephson hyperscaling rule can also break down in Ising systems with quenched random interactions. A related Renormalization Group Theory hyperscaling rule links the critical exponents for the normalized Binder cumulant and the correlation length in the thermodynamic limit. An appropriate scaling approach for analyzing measurements from criticality to infinite temperature is first outlined. Numerical data on the scaling of the normalized correlation length and the normalized Binder cumulant are shown for the canonical Ising ferromagnet model in dimension three where hyperscaling holds, for the Ising ferromagnet in dimension five (so above the upper critical dimension) where hyperscaling breaks down, and then for Ising spin glass models in dimension three where the quenched interactions are random. For the Ising spin glasses there is a breakdown of the normalized Binder cumulant hyperscaling relation in the thermodynamic limit regime, with a return to size independent Binder cumulant values in the finite-size scaling regime around the critical region.

  3. Models of Investor Forecasting Behavior — Experimental Evidence

    Directory of Open Access Journals (Sweden)

    Federico Bonetto


    Full Text Available Different forecasting behaviors affect investors’ trading decisions and lead to qualitatively different asset price trajectories. It has been shown in the literature that the weights that investors place on observed asset price changes when forecasting future price changes, and the nature of their confidence when price changes are forecast, determine whether price bubbles, price crashes, and unpredictable price cycles occur. In this paper, we report the results of behavioral experiments involving multiple investors who participated in a market for a virtual asset. Our goal is to study investors’ forecast formation. We conducted three experimental sessions with different participants in each session. We fit different models of forecast formation to the observed data. There is strong evidence that the investors forecast future prices by extrapolating past price changes, even when they know the fundamental value of the asset exactly and the extrapolated forecasts differ significantly from the fundamental value. The rational expectations hypothesis seems inconsistent with the observed forecasts. The forecasting models of all participants that best fit the observed forecasting data were of the type that cause price bubbles and cycles in dynamical systems models, and price bubbles and cycles ended up occurring in all three sessions.

  4. Personality and Depression: Explanatory Models and Review of the Evidence (United States)

    Klein, Daniel N.; Kotov, Roman; Bufferd, Sara J.


    Understanding the association between personality and depression has implications for elucidating etiology and comorbidity, identifying at-risk individuals, and tailoring treatment. We discuss seven major models that have been proposed to explain the relation between personality and depression, and we review key methodological issues, including study design, the heterogeneity of mood disorders, and the assessment of personality. We then selectively review the extensive empirical literature on the role of personality traits in depression in adults and children. Current evidence suggests that depression is linked to traits such as neuroticism/negative emotionality, extraversion/positive emotionality, and conscientiousness. Moreover, personality characteristics appear to contribute to the onset and course of depression through a variety of pathways. Implications for prevention and prediction of treatment response are discussed, as well as specific considerations to guide future research on the relation between personality and depression. PMID:21166535

  5. Behavioral, Modeling, and Electrophysiological Evidence for Supramodality in Human Metacognition. (United States)

    Faivre, Nathan; Filevich, Elisa; Solovey, Guillermo; Kühn, Simone; Blanke, Olaf


    Human metacognition, or the capacity to introspect on one's own mental states, has been mostly characterized through confidence reports in visual tasks. A pressing question is to what extent results from visual studies generalize to other domains. Answering this question allows determining whether metacognition operates through shared, supramodal mechanisms or through idiosyncratic, modality-specific mechanisms. Here, we report three new lines of evidence for decisional and postdecisional mechanisms arguing for the supramodality of metacognition. First, metacognitive efficiency correlated among auditory, tactile, visual, and audiovisual tasks. Second, confidence in an audiovisual task was best modeled using supramodal formats based on integrated representations of auditory and visual signals. Third, confidence in correct responses involved similar electrophysiological markers for visual and audiovisual tasks that are associated with motor preparation preceding the perceptual judgment. We conclude that the supramodality of metacognition relies on supramodal confidence estimates and decisional signals that are shared across sensory modalities. SIGNIFICANCE STATEMENT Metacognitive monitoring is the capacity to access, report, and regulate one's own mental states. In perception, this allows rating our confidence in what we have seen, heard, or touched. Although metacognitive monitoring can operate on different cognitive domains, we ignore whether it involves a single supramodal mechanism common to multiple cognitive domains or modality-specific mechanisms idiosyncratic to each domain. Here, we bring evidence in favor of the supramodality hypothesis by showing that participants with high metacognitive performance in one modality are likely to perform well in other modalities. Based on computational modeling and electrophysiology, we propose that supramodality can be explained by the existence of supramodal confidence estimates and by the influence of decisional cues on

  6. Cumulative social risk and obesity in early childhood. (United States)

    Suglia, Shakira F; Duarte, Cristiane S; Chambers, Earle C; Boynton-Jarrett, Renée


    The goal of this study was to examine the relationship between cumulative social adversity and childhood obesity among preschool-aged children (N = 1605) in the Fragile Families and Child Wellbeing Study. Maternal reports of intimate partner violence, food insecurity, housing insecurity, maternal depressive symptoms, maternal substance use, and father's incarceration were obtained when the child was 1 and 3 years of age. Two cumulative social risk scores were created by summing the 6 factors assessed at ages 1 and 3 years. Child height and weight were measured at 5 years of age. Logistic regression models stratified according to gender were used to estimate the association between cumulative social risk and obesity, adjusting for sociodemographic factors. Seventeen percent of children were obese at age 5 years, and 57% had at least 1 social risk factor. Adjusting for sociodemographic factors, girls experiencing high cumulative social risk (≥2 factors) at age 1 year only (odds ratio [OR]: 2.1 [95% confidence interval [CI]: 1.1-4.1]) or at 3 years only (OR: 2.2 [95% CI: 1.2-4.2]) were at increased odds of being obese compared with girls with no risk factors at either time point. Those experiencing high cumulative risk at age 1 and 3 years were not at statistically significant odds of being obese (OR: 1.9 [95% CI: 0.9-4.0]). No significant associations were noted among boys. There seems to be gender differences in the effects of cumulative social risk factors on the prevalence of obesity at 5 years of age. Understanding the social context of families could make for more effective preventive efforts to combat childhood obesity.

  7. Variable Cultural Acquisition Costs Constrain Cumulative Cultural Evolution (United States)

    Mesoudi, Alex


    One of the hallmarks of the human species is our capacity for cumulative culture, in which beneficial knowledge and technology is accumulated over successive generations. Yet previous analyses of cumulative cultural change have failed to consider the possibility that as cultural complexity accumulates, it becomes increasingly costly for each new generation to acquire from the previous generation. In principle this may result in an upper limit on the cultural complexity that can be accumulated, at which point accumulated knowledge is so costly and time-consuming to acquire that further innovation is not possible. In this paper I first review existing empirical analyses of the history of science and technology that support the possibility that cultural acquisition costs may constrain cumulative cultural evolution. I then present macroscopic and individual-based models of cumulative cultural evolution that explore the consequences of this assumption of variable cultural acquisition costs, showing that making acquisition costs vary with cultural complexity causes the latter to reach an upper limit above which no further innovation can occur. These models further explore the consequences of different cultural transmission rules (directly biased, indirectly biased and unbiased transmission), population size, and cultural innovations that themselves reduce innovation or acquisition costs. PMID:21479170

  8. Team-Based Models for End-of-Life Care: An Evidence-Based Analysis (United States)


    Background End of life refers to the period when people are living with advanced illness that will not stabilize and from which they will not recover and will eventually die. It is not limited to the period immediately before death. Multiple services are required to support people and their families during this time period. The model of care used to deliver these services can affect the quality of the care they receive. Objectives Our objective was to determine whether an optimal team-based model of care exists for service delivery at end of life. In systematically reviewing such models, we considered their core components: team membership, services offered, modes of patient contact, and setting. Data Sources A literature search was performed on October 14, 2013, using Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid Embase, EBSCO Cumulative Index to Nursing & Allied Health Literature (CINAHL), and EBM Reviews, for studies published from January 1, 2000, to October 14, 2013. Review Methods Abstracts were reviewed by a single reviewer and full-text articles were obtained that met the inclusion criteria. Studies were included if they evaluated a team model of care compared with usual care in an end-of-life adult population. A team was defined as having at least 2 health care disciplines represented. Studies were limited to English publications. A meta-analysis was completed to obtain pooled effect estimates where data permitted. The GRADE quality of the evidence was evaluated. Results Our literature search located 10 randomized controlled trials which, among them, evaluated the following 6 team-based models of care: hospital, direct contact home, direct contact home, indirect contact comprehensive, indirect contact comprehensive, direct contact comprehensive, direct, and early contact Direct contact is when team members see the patient; indirect contact is when they advise another health care practitioner (e.g., a family doctor) who sees

  9. Cumulative cultural learning: Development and diversity. (United States)

    Legare, Cristine H


    The complexity and variability of human culture is unmatched by any other species. Humans live in culturally constructed niches filled with artifacts, skills, beliefs, and practices that have been inherited, accumulated, and modified over generations. A causal account of the complexity of human culture must explain its distinguishing characteristics: It is cumulative and highly variable within and across populations. I propose that the psychological adaptations supporting cumulative cultural transmission are universal but are sufficiently flexible to support the acquisition of highly variable behavioral repertoires. This paper describes variation in the transmission practices (teaching) and acquisition strategies (imitation) that support cumulative cultural learning in childhood. Examining flexibility and variation in caregiver socialization and children's learning extends our understanding of evolution in living systems by providing insight into the psychological foundations of cumulative cultural transmission-the cornerstone of human cultural diversity.

  10. Cumulative risk effects for the development of behaviour difficulties in children and adolescents with special educational needs and disabilities. (United States)

    Oldfield, Jeremy; Humphrey, Neil; Hebron, Judith


    Research has identified multiple risk factors for the development of behaviour difficulties. What have been less explored are the cumulative effects of exposure to multiple risks on behavioural outcomes, with no study specifically investigating these effects within a population of young people with special educational needs and disabilities (SEND). Furthermore, it is unclear whether a threshold or linear risk model better fits the data for this population. The sample included 2660 children and 1628 adolescents with SEND. Risk factors associated with increases in behaviour difficulties over an 18-month period were summed to create a cumulative risk score, with this explanatory variable being added into a multi-level model. A quadratic term was then added to test the threshold model. There was evidence of a cumulative risk effect, suggesting that exposure to higher numbers of risk factors, regardless of their exact nature, resulted in increased behaviour difficulties. The relationship between risk and behaviour difficulties was non-linear, with exposure to increasing risk having a disproportionate and detrimental impact on behaviour difficulties in child and adolescent models. Interventions aimed at reducing behaviour difficulties need to consider the impact of multiple risk variables. Tailoring interventions towards those exposed to large numbers of risks would be advantageous. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. About the cumulants of periodic signals (United States)

    Barrau, Axel; El Badaoui, Mohammed


    This note studies cumulants of time series. These functions originating from the probability theory being commonly used as features of deterministic signals, their classical properties are examined in this modified framework. We show additivity of cumulants, ensured in the case of independent random variables, requires here a different hypothesis. Practical applications are proposed, in particular an analysis of the failure of the JADE algorithm to separate some specific periodic signals.

  12. Calculating Cumulative Binomial-Distribution Probabilities (United States)

    Scheuer, Ernest M.; Bowerman, Paul N.


    Cumulative-binomial computer program, CUMBIN, one of set of three programs, calculates cumulative binomial probability distributions for arbitrary inputs. CUMBIN, NEWTONP (NPO-17556), and CROSSER (NPO-17557), used independently of one another. Reliabilities and availabilities of k-out-of-n systems analyzed. Used by statisticians and users of statistical procedures, test planners, designers, and numerical analysts. Used for calculations of reliability and availability. Program written in C.

  13. A unified computational account of cumulative semantic, semantic blocking, and semantic distractor effects in picture naming. (United States)

    Roelofs, Ardi


    Computational models of lexical selection in spoken word production have been applied to semantic interference effects in picture naming response times obtained with continuous naming, blocked-cyclic naming, and picture-word interference paradigms. However, a unified computational account of the effects in the three paradigms is lacking. Here, I show that the inclusion of conceptual bias in the WEAVER++model (Levelt, Roelofs, & Meyer, 1999) explains cumulative semantic and semantic blocking effects while preserving the model's account of semantic distractor effects. The key assumptions of the account are (1) lexical selection by competition, and (2) a conceptual origin and lexical locus of the semantic effects. I provide a proof of concept of the account by reporting computer simulation results, addressing behavioral and neuroimaging evidence. The assumptions are sufficient for a unified account of semantic effects in the three paradigms, contrary to pessimistic views of this area. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Cumulative effects assessment: Does scale matter?

    International Nuclear Information System (INIS)

    Therivel, Riki; Ross, Bill


    Cumulative effects assessment (CEA) is (or should be) an integral part of environmental assessment at both the project and the more strategic level. CEA helps to link the different scales of environmental assessment in that it focuses on how a given receptor is affected by the totality of plans, projects and activities, rather than on the effects of a particular plan or project. This article reviews how CEAs consider, and could consider, scale issues: spatial extent, level of detail, and temporal issues. It is based on an analysis of Canadian project-level CEAs and UK strategic-level CEAs. Based on a review of literature and, especially, case studies with which the authors are familiar, it concludes that scale issues are poorly considered at both levels, with particular problems being unclear or non-existing cumulative effects scoping methodologies; poor consideration of past or likely future human activities beyond the plan or project in question; attempts to apportion 'blame' for cumulative effects; and, at the plan level, limited management of cumulative effects caused particularly by the absence of consent regimes. Scale issues are important in most of these problems. However both strategic-level and project-level CEA have much potential for managing cumulative effects through better siting and phasing of development, demand reduction and other behavioural changes, and particularly through setting development consent rules for projects. The lack of strategic resource-based thresholds constrains the robust management of strategic-level cumulative effects

  15. Origin of path independence between cumulative CO2 emissions and global warming (United States)

    Seshadri, Ashwin K.


    Observations and GCMs exhibit approximate proportionality between cumulative carbon dioxide (CO2) emissions and global warming. Here we identify sufficient conditions for the relationship between cumulative CO2 emissions and global warming to be independent of the path of CO2 emissions; referred to as "path independence". Our starting point is a closed form expression for global warming in a two-box energy balance model (EBM), which depends explicitly on cumulative emissions, airborne fraction and time. Path independence requires that this function can be approximated as depending on cumulative emissions alone. We show that path independence arises from weak constraints, occurring if the timescale for changes in cumulative emissions (equal to ratio between cumulative emissions and emissions rate) is small compared to the timescale for changes in airborne fraction (which depends on CO2 uptake), and also small relative to a derived climate model parameter called the damping-timescale, which is related to the rate at which deep-ocean warming affects global warming. Effects of uncertainties in the climate model and carbon cycle are examined. Large deep-ocean heat capacity in the Earth system is not necessary for path independence, which appears resilient to climate modeling uncertainties. However long time-constants in the Earth system carbon cycle are essential, ensuring that airborne fraction changes slowly with timescale much longer than the timescale for changes in cumulative emissions. Therefore path independence between cumulative emissions and warming cannot arise for short-lived greenhouse gases.

  16. Effect of cumulative exposure on nasal response to ozone

    Energy Technology Data Exchange (ETDEWEB)

    Henderson, R.F.; Hotchkiss, J.A.; Chang, I.Y.; Scott, B.R.; Harkema, J.R. (Inhalation Toxicology Research Institute, Albuquerque, NM (United States))


    To assess the potential health risks associated with exposure to low levels of ozone, it is essential to know if the ozone-induced responses are dependent on cumulative exposures or on the peak concentrations. To answer this question female F344/N rats, 11-13 weeks of age, were exposed to a matrix of equal concentration x time values that included exposures to 0, 0.12, 0.24, and 0.48 ppm ozone for 3, 6, 12, or 24 hr. the response of the nasal epithelium was measured as induced DNA synthesis determined by the uptake of bromodeoxyuridine (a thymidine analog) into epithelial cells lining the nasal anterior maxilloturbinates. No increased DNA synthesis was observed in rats exposed to 0.12 ppm ozone for any of the time periods. For exposures higher than 0.12 ppm ozone, the response of the nasal epithelium was similar for equal cumulative exposures. The responses, however, were not linearly related to the cumulative (concentration x time) exposures. It appeared that some mitigating factor was present which decreased the responses at the higher cumulative exposures. No frank toxicity or cellular necrosis was observed, indicating that sublethal cell damage was sufficient to induce DNA synthesis. A simple mathematical model was developed to describe the relationship between ozone exposure and the induction of DNA synthesis in the nasal epithelium. The model predicted that the threshold concentration of ozone for inducing DNA synthesis in the nasal epithelium was 0.1 +/- 0.1 ppm. For one measure of ozone toxicity (induced DNA synthesis) at a sensitive site in the respiratory tract (maxilloturbinates), the effects of ozone were dependent on cumulative exposures at concentrations > 0.12 ppm and within the time and concentration ranges used in this study.

  17. Cumulative creep damage for unidirectional composites under step loading (United States)

    Guedes, Rui Miranda


    The creep lifetime prediction of unidirectional composite materials under step loading, based on constant loading durability diagram, is analyzed for the two-step creep loading condition. For this purpose different nonlinear cumulative-damage laws are revisited and applied to predict creep lifetime. One possible approach to accounting for damage accumulation is provided by the continuum-damage mechanics (CDM). However, the CDM lifetime expression obtained for constant loading condition presents some drawbacks. Specifically, the upper stress range is not accommodated by CDM form. A modification of CDM is proposed, forcing the CDM to capture the short-term creep failure. It is proven that this modified CDM (MCDM) does not yield the same predictions as the Linear Cumulative-damage law (Miner's law). Predictions obtained from the nonlinear cumulative-damage laws are compared against synthetic lifetime generated by a micromechanical model that simulates unidirectional composites under two-step creep loading condition. Comparable deviations from Miner's law are obtained by the nonlinear cumulative-damage laws.

  18. Evidence for criticality in financial data (United States)

    Ruiz, G.; de Marcos, A. F.


    We provide evidence that cumulative distributions of absolute normalized returns for the 100 American companies with the highest market capitalization, uncover a critical behavior for different time scales Δt. Such cumulative distributions, in accordance with a variety of complex - and financial - systems, can be modeled by the cumulative distribution functions of q-Gaussians, the distribution function that, in the context of nonextensive statistical mechanics, maximizes a non-Boltzmannian entropy. These q-Gaussians are characterized by two parameters, namely ( q, β), that are uniquely defined by Δt. From these dependencies, we find a monotonic relationship between q and β, which can be seen as evidence of criticality. We numerically determine the various exponents which characterize this criticality.

  19. Assessing the implications of human land-use change for the transient climate response to cumulative carbon emissions

    International Nuclear Information System (INIS)

    Simmons, C T; Matthews, H D


    Recent research has shown evidence of a linear climate response to cumulative CO 2 emissions, which implies that the source, timing, and amount of emissions does not significantly influence the climate response per unit emission. Furthermore, these analyses have generally assumed that the climate response to land-use CO 2 emissions is equivalent to that of fossil fuels under the assumption that, once in the atmosphere, the radiative forcing induced by CO 2 is not sensitive to the emissions source. However, land-cover change also affects surface albedo and the strength of terrestrial carbon sinks, both of which have an additional climate effect. In this study, we use a coupled climate-carbon cycle model to assess the climate response to historical and future cumulative land-use CO 2 emissions, in order to compare it to the response to fossil fuel CO 2 . We find that when we isolate the CO 2 -induced (biogeochemical) temperature changes associated with land-use change, then the climate response to cumulative land-use emissions is equivalent to that of fossil fuel CO 2 . We show further that the globally-averaged albedo-induced biophysical cooling from land-use change is non-negligible and may be of comparable magnitude to the biogeochemical warming, with the result that the net climate response to land-use change is substantially different from a linear response to cumulative emissions. However, our new simulations suggest that the biophysical cooling from land-use change follows its own independent (negative) linear response to cumulative net land-use CO 2 emissions, which may provide a useful scaling factor for certain applications when evaluating the full transient climate response to emissions. (letter)

  20. Dynamic prediction of cumulative incidence functions by direct binomial regression. (United States)

    Grand, Mia K; de Witte, Theo J M; Putter, Hein


    In recent years there have been a series of advances in the field of dynamic prediction. Among those is the development of methods for dynamic prediction of the cumulative incidence function in a competing risk setting. These models enable the predictions to be updated as time progresses and more information becomes available, for example when a patient comes back for a follow-up visit after completing a year of treatment, the risk of death, and adverse events may have changed since treatment initiation. One approach to model the cumulative incidence function in competing risks is by direct binomial regression, where right censoring of the event times is handled by inverse probability of censoring weights. We extend the approach by combining it with landmarking to enable dynamic prediction of the cumulative incidence function. The proposed models are very flexible, as they allow the covariates to have complex time-varying effects, and we illustrate how to investigate possible time-varying structures using Wald tests. The models are fitted using generalized estimating equations. The method is applied to bone marrow transplant data and the performance is investigated in a simulation study. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Perspectives on cumulative risks and impacts. (United States)

    Faust, John B


    Cumulative risks and impacts have taken on different meanings in different regulatory and programmatic contexts at federal and state government levels. Traditional risk assessment methodologies, with considerable limitations, can provide a framework for the evaluation of cumulative risks from chemicals. Under an environmental justice program in California, cumulative impacts are defined to include exposures, public health effects, or environmental effects in a geographic area from the emission or discharge of environmental pollution from all sources, through all media. Furthermore, the evaluation of these effects should take into account sensitive populations and socioeconomic factors where possible and to the extent data are available. Key aspects to this potential approach include the consideration of exposures (versus risk), socioeconomic factors, the geographic or community-level assessment scale, and the inclusion of not only health effects but also environmental effects as contributors to impact. Assessments of this type extend the boundaries of the types of information that toxicologists generally provide for risk management decisions.

  2. Computer models and the evidence of anthropogenic climate change: An epistemology of variety-of-evidence inferences and robustness analysis. (United States)

    Vezér, Martin A


    To study climate change, scientists employ computer models, which approximate target systems with various levels of skill. Given the imperfection of climate models, how do scientists use simulations to generate knowledge about the causes of observed climate change? Addressing a similar question in the context of biological modelling, Levins (1966) proposed an account grounded in robustness analysis. Recent philosophical discussions dispute the confirmatory power of robustness, raising the question of how the results of computer modelling studies contribute to the body of evidence supporting hypotheses about climate change. Expanding on Staley's (2004) distinction between evidential strength and security, and Lloyd's (2015) argument connecting variety-of-evidence inferences and robustness analysis, I address this question with respect to recent challenges to the epistemology robustness analysis. Applying this epistemology to case studies of climate change, I argue that, despite imperfections in climate models, and epistemic constraints on variety-of-evidence reasoning and robustness analysis, this framework accounts for the strength and security of evidence supporting climatological inferences, including the finding that global warming is occurring and its primary causes are anthropogenic. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Cumulative Culture and Future Thinking: Is Mental Time Travel a Prerequisite to Cumulative Cultural Evolution? (United States)

    Vale, G. L.; Flynn, E. G.; Kendal, R. L.


    Cumulative culture denotes the, arguably, human capacity to build on the cultural behaviors of one's predecessors, allowing increases in cultural complexity to occur such that many of our cultural artifacts, products and technologies have progressed beyond what a single individual could invent alone. This process of cumulative cultural evolution…

  4. Modeling Sensor Reliability in Fault Diagnosis Based on Evidence Theory. (United States)

    Yuan, Kaijuan; Xiao, Fuyuan; Fei, Liguo; Kang, Bingyi; Deng, Yong


    Sensor data fusion plays an important role in fault diagnosis. Dempster-Shafer (D-R) evidence theory is widely used in fault diagnosis, since it is efficient to combine evidence from different sensors. However, under the situation where the evidence highly conflicts, it may obtain a counterintuitive result. To address the issue, a new method is proposed in this paper. Not only the statistic sensor reliability, but also the dynamic sensor reliability are taken into consideration. The evidence distance function and the belief entropy are combined to obtain the dynamic reliability of each sensor report. A weighted averaging method is adopted to modify the conflict evidence by assigning different weights to evidence according to sensor reliability. The proposed method has better performance in conflict management and fault diagnosis due to the fact that the information volume of each sensor report is taken into consideration. An application in fault diagnosis based on sensor fusion is illustrated to show the efficiency of the proposed method. The results show that the proposed method improves the accuracy of fault diagnosis from 81.19% to 89.48% compared to the existing methods.

  5. Managing regional cumulative effects of oil sands development in Alberta, Canada

    International Nuclear Information System (INIS)

    Spaling, H.; Zwier, J.


    This paper demonstrates an approach to regional cumulative effects management using the case of oil sands development in Alberta, Canada. The 17 existing, approved, or planned projects, all concentrated in a relatively small region, pose significant challenges for conducting and reviewing cumulative effects assessment (CEA) on a project-by-project basis. In response, stakeholders have initiated a regional cumulative effects management system that is among the first such initiatives anywhere. Advantages of this system include (1) more efficient gathering and sharing of information, including a common regional database, (2) setting acceptable regional environmental thresholds for all projects, (3) collaborative assessment of similar cumulative effects from related projects, (4) co-ordinated regulatory review and approval process for overlapping CEAs, and (5) institutional empowerment from a Regional Sustainable Development Strategy administered by a public authority. This case provides a model for integrating project-based CEA with regional management of cumulative effects. (author)

  6. A cumulant functional for static and dynamic correlation

    International Nuclear Information System (INIS)

    Hollett, Joshua W.; Hosseini, Hessam; Menzies, Cameron


    A functional for the cumulant energy is introduced. The functional is composed of a pair-correction and static and dynamic correlation energy components. The pair-correction and static correlation energies are functionals of the natural orbitals and the occupancy transferred between near-degenerate orbital pairs, rather than the orbital occupancies themselves. The dynamic correlation energy is a functional of the statically correlated on-top two-electron density. The on-top density functional used in this study is the well-known Colle-Salvetti functional. Using the cc-pVTZ basis set, the functional effectively models the bond dissociation of H 2 , LiH, and N 2 with equilibrium bond lengths and dissociation energies comparable to those provided by multireference second-order perturbation theory. The performance of the cumulant functional is less impressive for HF and F 2 , mainly due to an underestimation of the dynamic correlation energy by the Colle-Salvetti functional.

  7. Ecosystem assessment methods for cumulative effects at the regional scale

    International Nuclear Information System (INIS)

    Hunsaker, C.T.


    Environmental issues such as nonpoint-source pollution, acid rain, reduced biodiversity, land use change, and climate change have widespread ecological impacts and require an integrated assessment approach. Since 1978, the implementing regulations for the National Environmental Policy Act (NEPA) have required assessment of potential cumulative environmental impacts. Current environmental issues have encouraged ecologists to improve their understanding of ecosystem process and function at several spatial scales. However, management activities usually occur at the local scale, and there is little consideration of the potential impacts to the environmental quality of a region. This paper proposes that regional ecological risk assessment provides a useful approach for assisting scientists in accomplishing the task of assessing cumulative impacts. Critical issues such as spatial heterogeneity, boundary definition, and data aggregation are discussed. Examples from an assessment of acidic deposition effects on fish in Adirondack lakes illustrate the importance of integrated data bases, associated modeling efforts, and boundary definition at the regional scale

  8. 4D Near-Field Source Localization Using Cumulant

    Directory of Open Access Journals (Sweden)

    Junying Zhang


    Full Text Available This paper proposes a new cumulant-based algorithm to jointly estimate four-dimensional (4D source parameters of multiple near-field narrowband sources. Firstly, this approach proposes a new cross-array, and constructs five high-dimensional Toeplitz matrices using the fourth-order cumulants of some properly chosen sensor outputs; secondly, it forms a parallel factor (PARAFAC model in the cumulant domain using these matrices, and analyzes the unique low-rank decomposition of this model; thirdly, it jointly estimates the frequency, two-dimensional (2D directions-of-arrival (DOAs, and range of each near-field source from the matrices via the low-rank three-way array (TWA decomposition. In comparison with some available methods, the proposed algorithm, which efficiently makes use of the array aperture, can localize N−3 sources using N sensors. In addition, it requires neither pairing parameters nor multidimensional search. Simulation results are presented to validate the performance of the proposed method.

  9. 4D Near-Field Source Localization Using Cumulant

    Directory of Open Access Journals (Sweden)

    Zhao Feng


    Full Text Available This paper proposes a new cumulant-based algorithm to jointly estimate four-dimensional (4D source parameters of multiple near-field narrowband sources. Firstly, this approach proposes a new cross-array, and constructs five high-dimensional Toeplitz matrices using the fourth-order cumulants of some properly chosen sensor outputs; secondly, it forms a parallel factor (PARAFAC model in the cumulant domain using these matrices, and analyzes the unique low-rank decomposition of this model; thirdly, it jointly estimates the frequency, two-dimensional (2D directions-of-arrival (DOAs, and range of each near-field source from the matrices via the low-rank three-way array (TWA decomposition. In comparison with some available methods, the proposed algorithm, which efficiently makes use of the array aperture, can localize sources using sensors. In addition, it requires neither pairing parameters nor multidimensional search. Simulation results are presented to validate the performance of the proposed method.

  10. Is cumulated pyrethroid exposure associated with prediabetes?

    DEFF Research Database (Denmark)

    Hansen, Martin Rune; Jørs, Erik; Lander, Flemming


    Pyrethroids are a class of insecticides used widely for vector control programs. Acute pyrethroid poisoning is rare, but well documented, whereas effects of cumulative exposure are insufficiently described, including possible negative effect on glucose regulation. The objective of this study was ...

  11. Empirical Test Of The Ohlson Model: Evidence From The Mauritian ...

    African Journals Online (AJOL)

    . ... Journal of Business Research ... the existence of value relevance of accounting information in Mauritius Stock Market using the Ohlson model (1995), which encourages the adoption of the historical price model in value relevance studies, ...

  12. Model selection on solid ground: Rigorous comparison of nine ways to evaluate Bayesian model evidence. (United States)

    Schöniger, Anneli; Wöhling, Thomas; Samaniego, Luis; Nowak, Wolfgang


    Bayesian model selection or averaging objectively ranks a number of plausible, competing conceptual models based on Bayes' theorem. It implicitly performs an optimal trade-off between performance in fitting available data and minimum model complexity. The procedure requires determining Bayesian model evidence (BME), which is the likelihood of the observed data integrated over each model's parameter space. The computation of this integral is highly challenging because it is as high-dimensional as the number of model parameters. Three classes of techniques to compute BME are available, each with its own challenges and limitations: (1) Exact and fast analytical solutions are limited by strong assumptions. (2) Numerical evaluation quickly becomes unfeasible for expensive models. (3) Approximations known as information criteria (ICs) such as the AIC, BIC, or KIC (Akaike, Bayesian, or Kashyap information criterion, respectively) yield contradicting results with regard to model ranking. Our study features a theory-based intercomparison of these techniques. We further assess their accuracy in a simplistic synthetic example where for some scenarios an exact analytical solution exists. In more challenging scenarios, we use a brute-force Monte Carlo integration method as reference. We continue this analysis with a real-world application of hydrological model selection. This is a first-time benchmarking of the various methods for BME evaluation against true solutions. Results show that BME values from ICs are often heavily biased and that the choice of approximation method substantially influences the accuracy of model ranking. For reliable model selection, bias-free numerical methods should be preferred over ICs whenever computationally feasible.

  13. The Role of Empirical Evidence in Modeling Speech Segmentation (United States)

    Phillips, Lawrence


    Choosing specific implementational details is one of the most important aspects of creating and evaluating a model. In order to properly model cognitive processes, choices for these details must be made based on empirical research. Unfortunately, modelers are often forced to make decisions in the absence of relevant data. My work investigates the…

  14. Evidence-based practice models for organizational change: overview and practical applications. (United States)

    Schaffer, Marjorie A; Sandau, Kristin E; Diedrick, Lee


    To provide an overview, summary of key features and evaluation of usefulness of six evidence-based practice models frequently discussed in the literature. The variety of evidence-based practice models and frameworks, complex terminology and organizational culture challenges nurses in selecting the model that best fits their practice setting. The authors: (1) initially identified models described in a predominant nursing text; (2) searched the literature through CINAHL from 1998 to current year, using combinations of 'evidence', 'evidence-based practice', 'models', 'nursing' and 'research'; (3) refined the list of selected models based on the initial literature review; and (4) conducted a second search of the literature on the selected models for all available years to locate both historical and recent articles on their use in nursing practice. Authors described model key features and provided an evaluation of model usefulness based on specific criteria, which focused on facilitating the evidence-based practice process and guiding practice change. The evaluation of model usefulness can be used to determine the best fit of the models to the practice setting. The Johns Hopkins Model and the Academic Center for Evidence-Based Practice Star Model emphasize the processes of finding and evaluating evidence that is likely to appeal to nursing educators. Organizations may prefer the Promoting Action on Research Implementation in Health Services Framework, Advancing Research and Clinical Practice Through Close Collaboration, or Iowa models for their emphasis on team decision-making. An evidence-based practice model that is clear to the clinician and fits the organization will guide a systematic approach to evidence review and practice change. © 2012 Blackwell Publishing Ltd.

  15. Cumulative versus end-of-course assessment: effects on self-study time and test performance. (United States)

    Kerdijk, Wouter; Cohen-Schotanus, Janke; Mulder, B Florentine; Muntinghe, Friso L H; Tio, René A


    Students tend to postpone preparation for a test until the test is imminent, which raises various risks associated with 'cramming' behaviours, including that for suboptimal learning. Cumulative assessment utilises spaced testing to stimulate students to study more frequently and to prevent procrastination. This randomised controlled study investigated how cumulative assessment affects time spent on self-study and test performance compared with end-of-course assessment. A total of 78 undergraduate medical students in a Year 2 pre-clinical course were randomly assigned to either of two conditions. Students in the cumulative assessment condition were assessed in weeks 4, 8 and 10. Students in the end-of-course assessment condition were assessed in week 10 only. Each week, students reported the number of hours they spent on self-study. Students in the cumulative assessment condition (n = 25) spent significantly more time on self-study than students in the end-of-course assessment condition (n = 37) in all weeks of the course except weeks 5, 9 and 10. Overall, the cumulative assessment group spent 69 hours more on self-study during the course than did the control group, although the control group spent 7 hours more in studying during the final week of the course than did the cumulative assessment group. Students in the cumulative assessment condition scored slightly higher on questions concerning the content of the last part of the course. Cumulative assessment encourages students to distribute their learning activities over a course, which leaves them more opportunity to study the content of the last part of the course prior to the final examination. There was no evidence for a short-term effect of cumulative assessment on overall knowledge gain. We hypothesise that larger positive effects might be found if retention were to be measured in the long term. © 2015 John Wiley & Sons Ltd.

  16. Finite-volume cumulant expansion in QCD-colorless plasma

    Energy Technology Data Exchange (ETDEWEB)

    Ladrem, M. [Taibah University, Physics Department, Faculty of Science, Al-Madinah, Al-Munawwarah (Saudi Arabia); Physics Department, Algiers (Algeria); ENS-Vieux Kouba (Bachir El-Ibrahimi), Laboratoire de Physique et de Mathematiques Appliquees (LPMA), Algiers (Algeria); Ahmed, M.A.A. [Taibah University, Physics Department, Faculty of Science, Al-Madinah, Al-Munawwarah (Saudi Arabia); ENS-Vieux Kouba (Bachir El-Ibrahimi), Laboratoire de Physique et de Mathematiques Appliquees (LPMA), Algiers (Algeria); Taiz University in Turba, Physics Department, Taiz (Yemen); Alfull, Z.Z. [Taibah University, Physics Department, Faculty of Science, Al-Madinah, Al-Munawwarah (Saudi Arabia); Cherif, S. [ENS-Vieux Kouba (Bachir El-Ibrahimi), Laboratoire de Physique et de Mathematiques Appliquees (LPMA), Algiers (Algeria); Ghardaia University, Sciences and Technologies Department, Ghardaia (Algeria)


    Due to the finite-size effects, the localization of the phase transition in finite systems and the determination of its order, become an extremely difficult task, even in the simplest known cases. In order to identify and locate the finite-volume transition point T{sub 0}(V) of the QCD deconfinement phase transition to a colorless QGP, we have developed a new approach using the finite-size cumulant expansion of the order parameter and the L{sub mn}-method. The first six cumulants C{sub 1,2,3,4,5,6} with the corresponding under-normalized ratios (skewness Σ, kurtosis κ, pentosis Π{sub ±}, and hexosis H{sub 1,2,3}) and three unnormalized combinations of them, (O = σ{sup 2}κΣ{sup -1},U = σ{sup -2}Σ{sup -1},N = σ{sup 2}κ) are calculated and studied as functions of (T, V). A new approach, unifying in a clear and consistent way the definitions of cumulant ratios, is proposed.Anumerical FSS analysis of the obtained results has allowed us to locate accurately the finite-volume transition point. The extracted transition temperature value T{sub 0}(V) agrees with that expected T{sub 0}{sup N}(V) from the order parameter and the thermal susceptibility χ{sub T} (T, V), according to the standard procedure of localization to within about 2%. In addition to this, a very good correlation factor is obtained proving the validity of our cumulants method. The agreement of our results with those obtained by means of other models is remarkable. (orig.)

  17. Measuring Convergence using Dynamic Equilibrium Models: Evidence from Chinese Provinces

    DEFF Research Database (Denmark)

    Pan, Lei; Posch, Olaf; van der Wel, Michel

    We propose a model to study economic convergence in the tradition of neoclassical growth theory. We employ a novel stochastic set-up of the Solow (1956) model with shocks to both capital and labor. Our novel approach identifies the speed of convergence directly from estimating the parameters whic...

  18. No evidence for extensions to the standard cosmological model

    CSIR Research Space (South Africa)

    Heavens, A


    Full Text Available is not included. Many alternative models are strongly disfavoured by the data, including primordial correlated isocurvature models (lnB=-7.8), non-zero scalar-to-tensor ratio (lnB=-4.3), running of the spectral index (lnB=-4.7), curvature (lnB=-3.6), non...

  19. Evidence, models, conservation programs and limits to management (United States)

    Nichols, J.D.


    Walsh et al. (2012) emphasized the importance of obtaining evidence to assess the effects of management actions on state variables relevant to objectives of conservation programs. They focused on malleefowl Leipoa ocellata, ground-dwelling Australian megapodes listed as vulnerable. They noted that although fox Vulpes vulpes baiting is the main management action used in malleefowl conservation throughout southern Australia, evidence of the effectiveness of this action is limited and currently debated. Walsh et al. (2012) then used data from 64 sites monitored for malleefowl and foxes over 23 years to assess key functional relationships relevant to fox control as a conservation action for malleefowl. In one set of analyses, Walsh et al. (2012) focused on two relationships: fox baiting investment versus fox presence, and fox presence versus malleefowl population size and rate of population change. Results led to the counterintuitive conclusion that increases in investments in fox control produced slight decreases in malleefowl population size and growth. In a second set of analyses, Walsh et al. (2012) directly assessed the relationship between investment in fox baiting and malleefowl population size and rate of population change. This set of analyses showed no significant relationship between investment in fox population control and malleefowl population growth. Both sets of analyses benefited from the incorporation of key environmental covariates hypothesized to influence these management relationships. Walsh et al. (2012) concluded that "in most situations, malleefowl conservation did not effectively benefit from fox baiting at current levels of investment." In this commentary, I discuss the work of Walsh et al. (2012) using the conceptual framework of structured decision making (SDM). In doing so, I accept their analytic results and associated conclusions as accurate and discuss basic ideas about evidence, conservation and limits to management.

  20. Transforming Patient-Centered Care: Development of the Evidence Informed Decision Making through Engagement Model. (United States)

    Moore, Jennifer E; Titler, Marita G; Kane Low, Lisa; Dalton, Vanessa K; Sampselle, Carolyn M


    In response to the passage of the Affordable Care Act in the United States, clinicians and researchers are critically evaluating methods to engage patients in implementing evidence-based care to improve health outcomes. However, most models on implementation only target clinicians or health systems as the adopters of evidence. Patients are largely ignored in these models. A new implementation model that captures the complex but important role of patients in the uptake of evidence may be a critical missing link. Through a process of theory evaluation and development, we explore patient-centered concepts (patient activation and shared decision making) within an implementation model by mapping qualitative data from an elective induction of labor study to assess the model's ability to capture these key concepts. The process demonstrated that a new, patient-centered model for implementation is needed. In response, the Evidence Informed Decision Making through Engagement Model is presented. We conclude that, by fully integrating women into an implementation model, outcomes that are important to both the clinician and patient will improve. In the interest of providing evidence-based care to women during pregnancy and childbirth, it is essential that care is patient centered. The inclusion of concepts discussed in this article has the potential to extend beyond maternity care and influence other clinical areas. Utilizing the newly developed Evidence Informed Decision Making through Engagement Model provides a framework for utilizing evidence and translating it into practice while acknowledging the important role that women have in the process. Published by Elsevier Inc.

  1. Structure functions and particle production in the cumulative region: two different exponentials

    International Nuclear Information System (INIS)

    Braun, M.; Vechernin, V.


    In the framework of the recently proposed (QCD-based parton model for the cumulative phenomena in the interactions with nuclei two mechanisms for particle production, direct and spectator ones, are analyzed. It is shown that due to final-state interactions the leading terms of the direct mechanism contribution are cancelled and the spectator mechanism is the dominant one. It leads to a smaller slope of the cumulative particle production rates compared to the slope of the nuclear structure function in the cumulative region x ≥ 1, in agreement with the recent experimental data

  2. Power Reactor Docket Information. Annual cumulation (citations)

    International Nuclear Information System (INIS)


    An annual cumulation of the citations to the documentation associated with civilian nuclear power plants is presented. This material is that which is submitted to the U.S. Nuclear Regulatory Commission in support of applications for construction and operating licenses. Citations are listed by Docket number in accession number sequence. The Table of Contents is arranged both by Docket number and by nuclear power plant name

  3. Enabling Business Model Change: Evidence from High-Technology Firms

    Directory of Open Access Journals (Sweden)

    Christiana Müller


    Full Text Available Companies today face volatie environments, short product life cycles, and changing customer requirements, which is especially the case in high-technology filds. In such environments, concentratig only on technological and product innovatins is not suffient to gain competiie advantages. Instead, companies need innovatie business models in order to stand out from their competiors. To successfully change business models, companies require appropriate competencies. Thus, the objectie of this research is to identiy how companies can prepare their business model(s to counteract environmental changes flxibly. With the aid of the chosen exploratory, qualitatie research design, we investiate companies operatig in hightechnology branches. In total, 20 companies partiipated in our study. The interviews were conducted with CEOs, vice-presidents, product managers or other managers responsible for business model developments. The research revealed that companies can prepare the business model and its elements ex ante through developing capabilitis in order to raise the flxibility of the business model. These capabilitis have to be developed with regard to several internal and external issues driving these changes.

  4. Selection Bias in Educational Transition Models: Theory and Empirical Evidence

    DEFF Research Database (Denmark)

    Holm, Anders; Jæger, Mads

    Most studies using Mare’s (1980, 1981) seminal model of educational transitions find that the effect of family background decreases across transitions. Recently, Cameron and Heckman (1998, 2001) have argued that the “waning coefficients” in the Mare model are driven by selection on unobserved...... the United States, United Kingdom, Denmark, and the Netherlands shows that when we take selection into account the effect of family background variables on educational transitions is largely constant across transitions. We also discuss several difficulties in estimating educational transition models which...

  5. Experimental and modeling evidence of appendicularian-ciliate interactions

    DEFF Research Database (Denmark)

    Lombard, Fabien; Eloire, D.; Gobet, A.

    Interactions between appendicularians and ciliates were observed over the life span of Oikopleura dioica in laboratory cultures and clarified with the use of mathematical modeling and microscopic observations. Complex interactions including competition, parasitism, predation, and histophagy...

  6. Experimental and modeling evidence of appendicularian-ciliate interactions

    DEFF Research Database (Denmark)

    Lombard, Fabien; Eloire, Damien; Gobet, Angelique


    Interactions between appendicularians and ciliates were observed over the life span of Oikopleura dioica in laboratory cultures and clarified with the use of mathematical modeling and microscopic observations. Complex interactions including competition, parasitism, predation, and histophagy...

  7. Structural investigations on an amorphous Se90Te10 alloy produced by mechanical alloying using EXAFS, cumulant expansion and RMC simulations. (United States)

    Kostrzepa, I M; Siqueira, M C; Machado, K D; Maciel, G A; Sanchez, D F; Brunatto, S F


    We investigated an amorphous Se(90)Te(10) alloy produced by mechanical alloying using two different approaches. First, we used extended x-ray absorption fine structure (EXAFS) spectroscopy and the cumulant expansion method using the Einstein model for the temperature dependence of the cumulants to obtain the cumulants C(*)(1), C(*)(2), and C(*)(3). From these, we found information about the structure of the alloy as well as the thermal and structural disorder, anharmonicity of the effective interatomic pair potentials, thermal expansion of the Se-Se and Se-Te bonds and asymmetry of the partial distribution functions g(Se-Se)(r) and g(Se-Te)(r). The cumulants C(*)(1), C(*)(2), and C(*)(3) also allowed us to reconstruct the g(EXAFS)(ij)(r,T) functions from EXAFS. Then, we made reverse Monte Carlo (RMC) simulations using the total structure factor S(K) obtained from synchrotron x-ray diffraction and the EXAFS oscillations χ(k) on the Se K edge as input data to obtain the g(RMC)(ij)(r) functions. Both methods furnished very similar g(ij)(r) functions, and the structural data obtained from them were also very similar. The results obtained from both methods showed the presence of Se-Te pairs indicating that there is alloying at the atomic level. In addition, we could not find any evidence of the presence of Te clusters in the alloy. © 2012 IOP Publishing Ltd

  8. Endogenizing technological change. Matching empirical evidence to modeling needs

    Energy Technology Data Exchange (ETDEWEB)

    Pizer, William A. [Resources for the Future, 1616 P Street NW, Washington, DC, 20009 (United States); Popp, David [Department of Public Administration, Center for Policy Research, The Maxwell School, Syracuse University, 426 Eggers Hall, Syracuse, NY 13244-1020 (United States); National Bureau of Economic Research (United States)


    Given that technologies to significantly reduce fossil fuel emissions are currently unavailable or only available at high cost, technological change will be a key component of any long-term strategy to reduce greenhouse gas emissions. In light of this, the amount of research on the pace, direction, and benefits of environmentally-friendly technological change has grown dramatically in recent years. This research includes empirical work estimating the magnitude of these effects, and modeling exercises designed to simulate the importance of endogenous technological change in response to climate policy. Unfortunately, few attempts have been made to connect these two streams of research. This paper attempts to bridge that gap. We review both the empirical and modeling literature on technological change. Our focus includes the research and development process, learning by doing, the role of public versus private research, and technology diffusion. Our goal is to provide an agenda for how both empirical and modeling research in these areas can move forward in a complementary fashion. In doing so, we discuss both how models used for policy evaluation can better capture empirical phenomena, and how empirical research can better address the needs of models used for policy evaluation. (author)

  9. Endogenizing technological change: Matching empirical evidence to modeling needs

    Energy Technology Data Exchange (ETDEWEB)

    Pizer, William A. [Resources for the Future, 1616 P Street NW, Washington, DC, 20009 (United States)], E-mail:; Popp, David [Department of Public Administration, Center for Policy Research, Maxwell School, Syracuse University, 426 Eggers Hall, Syracuse, NY 13244-1020 (United States); National Bureau of Economic Research (United States)], E-mail:


    Given that technologies to significantly reduce fossil fuel emissions are currently unavailable or only available at high cost, technological change will be a key component of any long-term strategy to reduce greenhouse gas emissions. In light of this, the amount of research on the pace, direction, and benefits of environmentally-friendly technological change has grown dramatically in recent years. This research includes empirical work estimating the magnitude of these effects, and modeling exercises designed to simulate the importance of endogenous technological change in response to climate policy. Unfortunately, few attempts have been made to connect these two streams of research. This paper attempts to bridge that gap. We review both the empirical and modeling literature on technological change. Our focus includes the research and development process, learning by doing, the role of public versus private research, and technology diffusion. Our goal is to provide an agenda for how both empirical and modeling research in these areas can move forward in a complementary fashion. In doing so, we discuss both how models used for policy evaluation can better capture empirical phenomena, and how empirical research can better address the needs of models used for policy evaluation.

  10. The protective action decision model: theoretical modifications and additional evidence. (United States)

    Lindell, Michael K; Perry, Ronald W


    The Protective Action Decision Model (PADM) is a multistage model that is based on findings from research on people's responses to environmental hazards and disasters. The PADM integrates the processing of information derived from social and environmental cues with messages that social sources transmit through communication channels to those at risk. The PADM identifies three critical predecision processes (reception, attention, and comprehension of warnings or exposure, attention, and interpretation of environmental/social cues)--that precede all further processing. The revised model identifies three core perceptions--threat perceptions, protective action perceptions, and stakeholder perceptions--that form the basis for decisions about how to respond to an imminent or long-term threat. The outcome of the protective action decision-making process, together with situational facilitators and impediments, produces a behavioral response. In addition to describing the revised model and the research on which it is based, this article describes three applications (development of risk communication programs, evacuation modeling, and adoption of long-term hazard adjustments) and identifies some of the research needed to address unresolved issues. © 2011 Society for Risk Analysis.

  11. Physics of human cooperation: experimental evidence and theoretical models (United States)

    Sánchez, Angel


    In recent years, many physicists have used evolutionary game theory combined with a complex systems perspective in an attempt to understand social phenomena and challenges. Prominent among such phenomena is the issue of the emergence and sustainability of cooperation in a networked world of selfish or self-focused individuals. The vast majority of research done by physicists on these questions is theoretical, and is almost always posed in terms of agent-based models. Unfortunately, more often than not such models ignore a number of facts that are well established experimentally, and are thus rendered irrelevant to actual social applications. I here summarize some of the facts that any realistic model should incorporate and take into account, discuss important aspects underlying the relation between theory and experiments, and discuss future directions for research based on the available experimental knowledge.

  12. Numerical Demons in Monte Carlo Estimation of Bayesian Model Evidence with Application to Soil Respiration Models (United States)

    Elshall, A. S.; Ye, M.; Niu, G. Y.; Barron-Gafford, G.


    Bayesian multimodel inference is increasingly being used in hydrology. Estimating Bayesian model evidence (BME) is of central importance in many Bayesian multimodel analysis such as Bayesian model averaging and model selection. BME is the overall probability of the model in reproducing the data, accounting for the trade-off between the goodness-of-fit and the model complexity. Yet estimating BME is challenging, especially for high dimensional problems with complex sampling space. Estimating BME using the Monte Carlo numerical methods is preferred, as the methods yield higher accuracy than semi-analytical solutions (e.g. Laplace approximations, BIC, KIC, etc.). However, numerical methods are prone the numerical demons arising from underflow of round off errors. Although few studies alluded to this issue, to our knowledge this is the first study that illustrates these numerical demons. We show that the precision arithmetic can become a threshold on likelihood values and Metropolis acceptance ratio, which results in trimming parameter regions (when likelihood function is less than the smallest floating point number that a computer can represent) and corrupting of the empirical measures of the random states of the MCMC sampler (when using log-likelihood function). We consider two of the most powerful numerical estimators of BME that are the path sampling method of thermodynamic integration (TI) and the importance sampling method of steppingstone sampling (SS). We also consider the two most widely used numerical estimators, which are the prior sampling arithmetic mean (AS) and posterior sampling harmonic mean (HM). We investigate the vulnerability of these four estimators to the numerical demons. Interesting, the most biased estimator, namely the HM, turned out to be the least vulnerable. While it is generally assumed that AM is a bias-free estimator that will always approximate the true BME by investing in computational effort, we show that arithmetic underflow can

  13. An Evidence-Based Practitioner's Model for Adolescent Leadership Development (United States)

    Rehm, Christopher J.


    This paper proposes a model for youth leadership education based on adolescent development and leadership research in an effort to provide practitioners with a practical blueprint to aid their creation and implementation of high school leadership programs. By focusing on student leader development areas which school level educators can affect,…

  14. Evidence for the multiverse in the standard model and beyond (United States)

    Hall, Lawrence J.; Nomura, Yasunori


    In any theory it is unnatural if the observed values of parameters lie very close to special values that determine the existence of complex structures necessary for observers. A naturalness probability P is introduced to numerically evaluate the degree of unnaturalness. If P is very small in all known theories, corresponding to a high degree of fine-tuning, then there is an observer naturalness problem. In addition to the well-known case of the cosmological constant, we argue that nuclear stability and electroweak symmetry breaking represent significant observer naturalness problems. The naturalness probability associated with nuclear stability depends on the theory of flavor, but for all known theories is conservatively estimated as Pnuc≲(10-3 10-2), and for simple theories of electroweak symmetry breaking PEWSB≲(10-2 10-1). This pattern of unnaturalness in three different arenas, cosmology, nuclear physics, and electroweak symmetry breaking, provides evidence for the multiverse, since each problem may be easily solved by environmental selection. In the nuclear case the problem is largely solved even if the multiverse distribution for the relevant parameters is relatively flat. With somewhat strongly varying distributions, it is possible to understand both the close proximity to neutron stability and the values of me and md-mu in terms of the electromagnetic mass difference between the proton and neutron, δEM≃1±0.5MeV. It is reasonable that multiverse distributions are strong functions of Lagrangian parameters, since they depend not only on the landscape of vacua, but also on the population mechanism, “integrating out” other parameters, and on a density of observers factor. In any theory with mass scale M that is the origin of electroweak symmetry breaking, strongly varying multiverse distributions typically lead either to a little hierarchy v/M≈(10-2 10-1), or to a large hierarchy v≪M. In certain multiverses, where electroweak symmetry breaking

  15. Neurorestoratology evidence in an animal model with cervical spondylotic myelopathy

    Directory of Open Access Journals (Sweden)

    Li X


    Full Text Available Xiang Li,1,2 Guangsheng Li,1,3 Keith Dip-Kei Luk,1 Yong Hu1–3 1Department of Orthopaedics and Traumatology, The University of Hong Kong, Pokfulam, Hong Kong, 2Shenzhen Key Laboratory for Innovative Technology in Orthopaedic Trauma, The University of Hong Kong-Shenzhen Hospital, Shenzhen, 3Spinal Division, Department of Orthopaedics, Affiliated Hospital of Guangdong Medical University, Guangdong, People’s Republic of China Background: Cervical spondylotic myelopathy (CSM is a chronic compression injury of the spinal cord, with potentially reversible conditions after surgical decompression, and a unique model of incomplete spinal cord injury. Several animal studies showed pathological changes of demyelination, axon loss and neuron apoptosis in rats with chronic spinal cord compression. However, there is a limited understanding of the neurological change in the spinal cord after surgical decompression. The aim of this study was to validate the neurorestoratology of myelopathic lesions in the spinal cord in a rat model. Materials and methods: A total of 16 adult Sprague-Dawley rats were divided into four groups: sham control (group 1; CSM model with 4-week chronic compression (group 2, 2 weeks (group 3 and 4 weeks (group 4 after surgical decompression of CSM model. The compression and decompression were verified by magnetic resonance imaging (MRI test. Neurological function was evaluated by Basso, Beattie, and Bresnahan (BBB locomotor rating scale, ladder rung walking test and somatosensory-evoked potentials (SEPs. Neuropathological change was evaluated by histological examinations. Results: MRI confirmed the compression of the cervical spinal cord as well as the reshaping of cord morphology after decompression. After decompression, significant changes of neurological function were observed in BBB scores (p < 0.01, F = 10.52, ladder rung walking test (p < 0.05, F = 14.21 and latencies (p < 0.05, F = 5.76 and amplitudes (p < 0.05, F = 3.8 of

  16. Corruption Around the World: Evidence from a Structural Model


    Axel Dreher; Christos Kotsogiannis; Steve McCorriston


    The causes and consequences of corruption have attracted much attention in recent years by both academics and policy makers. Central in the discussion on the impact of corruption are perception-based indices. While informative, these indices are ordinal in nature and hence provide no indication of how much economic loss is attributed to corruption. Arguably, this shortcoming is rooted in the lack of a structural model. This is the issue addressed in this paper. By treating corruption as a lat...

  17. Fatigue crack initiation in crystalline materials - experimental evidence and models

    Czech Academy of Sciences Publication Activity Database

    Polák, Jaroslav; Man, Jiří; Vystavěl, T.; Zouhar, Lukáš


    Roč. 345-346, - (2007), s. 379-382 ISSN 1013-9826. [International Conference on The Mechanical Behavior of Materials /10./. Busan , 27.05.2007-31.05.2007] R&D Projects: GA ČR GA106/06/1096; GA ČR GA101/07/1500 Institutional research plan: CEZ:AV0Z20410507 Keywords : fatigue * crack initiation * modeling Subject RIV: JL - Materials Fatigue, Friction Mechanics Impact factor: 0.224, year: 2005

  18. Cumulative impacts of mountaintop mining on an Appalachian watershed. (United States)

    Lindberg, T Ty; Bernhardt, Emily S; Bier, Raven; Helton, A M; Merola, R Brittany; Vengosh, Avner; Di Giulio, Richard T


    Mountaintop mining is the dominant form of coal mining and the largest driver of land cover change in the central Appalachians. The waste rock from these surface mines is disposed of in the adjacent river valleys, leading to a burial of headwater streams and dramatic increases in salinity and trace metal concentrations immediately downstream. In this synoptic study we document the cumulative impact of more than 100 mining discharge outlets and approximately 28 km(2) of active and reclaimed surface coal mines on the Upper Mud River of West Virginia. We measured the concentrations of major and trace elements within the tributaries and the mainstem and found that upstream of the mines water quality was equivalent to state reference sites. However, as eight separate mining-impacted tributaries contributed their flow, conductivity and the concentrations of selenium, sulfate, magnesium, and other inorganic solutes increased at a rate directly proportional to the upstream areal extent of mining. We found strong linear correlations between the concentrations of these contaminants in the river and the proportion of the contributing watershed in surface mines. All tributaries draining mountaintop-mining-impacted catchments were characterized by high conductivity and increased sulfate concentration, while concentrations of some solutes such as Se, Sr, and N were lower in the two tributaries draining reclaimed mines. Our results demonstrate the cumulative impact of multiple mines within a single catchment and provide evidence that mines reclaimed nearly two decades ago continue to contribute significantly to water quality degradation within this watershed.

  19. Extending the relationship between global warming and cumulative carbon emissions to multi-millennial timescales

    International Nuclear Information System (INIS)

    Frölicher, Thomas L; Paynter, David J


    The transient climate response to cumulative carbon emissions (TCRE) is a highly policy-relevant quantity in climate science. The TCRE suggests that peak warming is linearly proportional to cumulative carbon emissions and nearly independent of the emissions scenario. Here, we use simulations of the Earth System Model (ESM) from the Geophysical Fluid Dynamics Laboratory (GFDL) to show that global mean surface temperature may increase by 0.5 °C after carbon emissions are stopped at 2 °C global warming, implying an increase in the coefficient relating global warming to cumulative carbon emissions on multi-centennial timescales. The simulations also suggest a 20% lower quota on cumulative carbon emissions allowed to achieve a policy-driven limit on global warming. ESM estimates from the Coupled Model Intercomparison Project Phase 5 (CMIP5–ESMs) qualitatively agree on this result, whereas Earth System Models of Intermediate Complexity (EMICs) simulations, used in the IPCC 5th assessment report to assess the robustness of TCRE on multi-centennial timescales, suggest a post-emissions decrease in temperature. The reason for this discrepancy lies in the smaller simulated realized warming fraction in CMIP5–ESMs, including GFDL ESM2M, than in EMICs when carbon emissions increase. The temperature response to cumulative carbon emissions can be characterized by three different phases and the linear TCRE framework is only valid during the first phase when carbon emissions increase. For longer timescales, when emissions tape off, two new metrics are introduced that better characterize the time-dependent temperature response to cumulative carbon emissions: the equilibrium climate response to cumulative carbon emissions and the multi-millennial climate response to cumulative carbon emissions. (letter)

  20. Cumulant expansions for measuring water exchange using diffusion MRI (United States)

    Ning, Lipeng; Nilsson, Markus; Lasič, Samo; Westin, Carl-Fredrik; Rathi, Yogesh


    The rate of water exchange across cell membranes is a parameter of biological interest and can be measured by diffusion magnetic resonance imaging (dMRI). In this work, we investigate a stochastic model for the diffusion-and-exchange of water molecules. This model provides a general solution for the temporal evolution of dMRI signal using any type of gradient waveform, thereby generalizing the signal expressions for the Kärger model. Moreover, we also derive a general nth order cumulant expansion of the dMRI signal accounting for water exchange, which has not been explored in earlier studies. Based on this analytical expression, we compute the cumulant expansion for dMRI signals for the special case of single diffusion encoding (SDE) and double diffusion encoding (DDE) sequences. Our results provide a theoretical guideline on optimizing experimental parameters for SDE and DDE sequences, respectively. Moreover, we show that DDE signals are more sensitive to water exchange at short-time scale but provide less attenuation at long-time scale than SDE signals. Our theoretical analysis is also validated using Monte Carlo simulations on synthetic structures.

  1. A Cumulant-based Analysis of Nonlinear Magnetospheric Dynamics

    International Nuclear Information System (INIS)

    Johnson, Jay R.; Wing, Simon


    Understanding magnetospheric dynamics and predicting future behavior of the magnetosphere is of great practical interest because it could potentially help to avert catastrophic loss of power and communications. In order to build good predictive models it is necessary to understand the most critical nonlinear dependencies among observed plasma and electromagnetic field variables in the coupled solar wind/magnetosphere system. In this work, we apply a cumulant-based information dynamical measure to characterize the nonlinear dynamics underlying the time evolution of the Dst and Kp geomagnetic indices, given solar wind magnetic field and plasma input. We examine the underlying dynamics of the system, the temporal statistical dependencies, the degree of nonlinearity, and the rate of information loss. We find a significant solar cycle dependence in the underlying dynamics of the system with greater nonlinearity for solar minimum. The cumulant-based approach also has the advantage that it is reliable even in the case of small data sets and therefore it is possible to avoid the assumption of stationarity, which allows for a measure of predictability even when the underlying system dynamics may change character. Evaluations of several leading Kp prediction models indicate that their performances are sub-optimal during active times. We discuss possible improvements of these models based on this nonparametric approach

  2. Individual Impact Magnitude vs. Cumulative Magnitude for Estimating Concussion Odds. (United States)

    O'Connor, Kathryn L; Peeters, Thomas; Szymanski, Stefan; Broglio, Steven P


    Helmeted impact devices have allowed researchers to investigate the biomechanics of head impacts in vivo. While increased impact magnitude has been associated with greater concussion risk, a definitive concussive threshold has not been established. It is likely that concussion risk is not determined by a single impact itself, but a host of predisposing factors. These factors may include genetics, fatigue, and/or prior head impact exposure. The objective of the current paper is to investigate the association between cumulative head impact magnitude and concussion risk. It is hypothesized that increased cumulative magnitudes will be associated with greater concussion risk. This retrospective analysis included participants that were recruited from regional high-schools in Illinois and Michigan from 2007 to 2014 as part of an ongoing study on concussion biomechanics. Across seven seasons, 185 high school football athletes were instrumented with the Head Impact Telemetry system. Out of 185 athletes, 31 (17%) sustained a concussion, with two athletes sustaining two concussions over the study period, yielding 33 concussive events. The system recorded 78,204 impacts for all concussed players. Linear acceleration, rotational acceleration, and head impact telemetry severity profile (HITsp) magnitudes were summed within five timeframes: the day of injury, three days prior to injury, seven days prior to injury, 30 days prior to injury, and prior in-season exposure. Logistic regressions were modeled to explain concussive events based on the singular linear acceleration, rotational acceleration, and HITsp event along with the calculated summations over time. Linear acceleration, rotational acceleration, and HITsp all produced significant models estimating concussion (p concussive impact were the linear acceleration (OR = 1.040, p concussion likelihood. Cumulative magnitude is a simplistic measure of the total exposure sustained by a player over a given period. However, this

  3. Cumulative subgroup analysis to reduce waste in clinical research for individualised medicine. (United States)

    Song, Fujian; Bachmann, Max O


    Although subgroup analyses in clinical trials may provide evidence for individualised medicine, their conduct and interpretation remain controversial. Subgroup effect can be defined as the difference in treatment effect across patient subgroups. Cumulative subgroup analysis refers to a series of repeated pooling of subgroup effects after adding data from each of related trials chronologically, to investigate the accumulating evidence for subgroup effects. We illustrated the clinical relevance of cumulative subgroup analysis in two case studies using data from published individual patient data (IPD) meta-analyses. Computer simulations were also conducted to examine the statistical properties of cumulative subgroup analysis. In case study 1, an IPD meta-analysis of 10 randomised trials (RCTs) on beta blockers for heart failure reported significant interaction of treatment effects with baseline rhythm. Cumulative subgroup analysis could have detected the subgroup effect 15 years earlier, with five fewer trials and 71% less patients, than the IPD meta-analysis which first reported it. Case study 2 involved an IPD meta-analysis of 11 RCTs on treatments for pulmonary arterial hypertension that reported significant subgroup effect by aetiology. Cumulative subgroup analysis could have detected the subgroup effect 6 years earlier, with three fewer trials and 40% less patients than the IPD meta-analysis. Computer simulations have indicated that cumulative subgroup analysis increases the statistical power and is not associated with inflated false positives. To reduce waste of research data, subgroup analyses in clinical trials should be more widely conducted and adequately reported so that cumulative subgroup analyses could be timely performed to inform clinical practice and further research.

  4. Preserved cumulative semantic interference despite amnesia

    Directory of Open Access Journals (Sweden)

    Gary Michael Oppenheim


    As predicted by Oppenheim et al’s (2010 implicit incremental learning account, WRP’s BCN RTs demonstrated strong (and significant repetition priming and semantic blocking effects (Figure 1. Similar to typical results from neurally intact undergraduates, WRP took longer to name pictures presented in semantically homogeneous blocks than in heterogeneous blocks, an effect that increased with each cycle. This result challenges accounts that ascribe cumulative semantic interference in this task to explicit memory mechanisms, instead suggesting that the effect has the sort of implicit learning bases that are typically spared in hippocampal amnesia.

  5. The Atavistic Model of Cancer: Evidence, Objections, Therapeutic Value (United States)

    Lineweaver, Charles


    As cancer progresses tumor cells dedifferentiate. In the atavistic model this dedifferentiation is interpreted as a reversion to phylogenetically earlier capabilities (Davies & Lineweaver 2011). Since there is an identifiable order to the evolution of capabilities, the more recently evolved capabilities are more likely to be compromised first during cancer progression. A loss of capabilities based on the phylogenetic order of evolution suggests a therapeutic strategy for targeting cancer - design challenges that can only be met by the recently evolved capabilities still intact in normal cells, but lost in cancer cells. Such a target-the-weakness therapeutic strategy contrasts with most current therapies that target the main strength of cancer: cell proliferation. Here, we describe several examples of this target-the-weakness strategy. Our most detailed example involves the immune system. As cancer progresses, the atavistic model suggests that cancer cells lose contact with the more recently evolved adaptive immune system of the host (the basis of vaccination). The absence of adaptive immunity in immunosuppressed tumor environments is an irreversible weakness of cancer that can be exploited by creating a challenge that only the presence of adaptive immunity can meet. Thus, we propose the post-vaccination inoculation of disease at dosages that the recently evolved (and vaccination-primed) adaptive immune system will be able to destroy in normal cells, but not in the immunosuppressed microenvironment of tumor cells. Co-author: Paul Davies (Arizona State University)


    Directory of Open Access Journals (Sweden)

    Mohamad Husam Helmi


    Full Text Available This paper estimates the monetary policy reaction function for two sets of MENAcountries: The inflation target countries, (Turkeyand Israel and the exchange ratetarget countries, (Jordan and Morocco. We motivateour empirical analysis byanalyzing a simple Taylor rule. This model looks atthe effects of inflation andoutput on setting the interest rate by the centralbank. Furthermore, we extendedour model by adding the exchange rate and the foreign interest rate using similarmodel used by Clarida et al (1998 with using GMM estimator.Findings of this study yield some interesting results,all the central banks in thesample uses interest rate smoothing in managing their monetary policy. Inaddition, The Central bank in Turkey, Israel and Morocco focuses on achievinglow level of inflation. On the other hand, the Monetary Authority in Jordan caresabout stabilizing the output gap. Estimating the extended Taylor rule suggests thehighly significant effect of foreign interest rateon setting the interest rate inTurkey. Taken all together, the results lend support to the importance of followinga rule rather than discretionary in reducing the inflation rate and crediblemonetary policy. In addition, the simple Taylor rule can be applied on MENAcountries but it requires some modification such asadding the exchange rate andthe foreign interest rate.

  7. A stochastic multicriteria model for evidence-based decision making in drug benefit-risk analysis

    NARCIS (Netherlands)

    Tervonen, Tommi; van Valkenhoef, Gert; Buskens, Erik; Hillege, Hans L.; Postmus, Douwe


    Drug benefit-risk (BR) analysis is based on firm clinical evidence regarding various safety and efficacy outcomes. In this paper, we propose a new and more formal approach for constructing a supporting multicriteria model that fully takes into account the evidence on efficacy and adverse drug

  8. Chimpanzees (Pan troglodytes) and the question of cumulative culture: an experimental approach. (United States)

    Marshall-Pescini, Sarah; Whiten, Andrew


    There is increasing evidence for cultural variations in behaviour among non-human species, but human societies additionally display elaborate cumulative cultural evolution, with successive generations building on earlier achievements. Evidence for cumulative culture in non-human species remains minimal and controversial. Relevant experiments are also lacking. Here we present a first experiment designed to examine chimpanzees' capacity for cumulative social learning. Eleven young chimpanzees were presented with a foraging device, which afforded both a relatively simple and a more complex tool-use technique for extracting honey. The more complex 'probing' technique incorporated the core actions of the simpler 'dipping' one and was also much more productive. In a baseline, exploration condition only two subjects discovered the dipping technique and a solitary instance of probing occurred. Demonstrations of dipping by a familiar human were followed by acquisition of this technique by the five subjects aged three years or above, whilst younger subjects showed a significant increase only in the elements of the dipping technique. By contrast, subsequent demonstrations of the probing task were not followed by acquisition of this more productive technique. Subjects stuck to their habitual dipping method despite an escalating series of demonstrations eventually exceeding 200. Supplementary tests showed this technique is within the capability of chimpanzees of this age. We therefore tentatively conclude that young chimpanzees exhibit a tendency to become 'stuck' on a technique they initially learn, inhibiting cumulative social learning and possibly constraining the species' capacity for cumulative cultural evolution.

  9. Long and Short Term Cumulative Structural Priming Effects


    Kaschak, Michael P.; Kutta, Timothy J.; Coyle, Jacqueline M.


    We present six experiments that examine cumulative structural priming effects (i.e., structural priming effects that accumulate across many utterances). Of particular interest is whether (1) cumulative priming effects transfer across language production tasks and (2) the transfer of cumulative priming effects across tasks persists over the course of a week. Our data suggest that cumulative structural priming effects do transfer across language production tasks (e.g., from written stem complet...

  10. Rainfall Intensity and Frequency Explain Production Basis Risk in Cumulative Rain Index Insurance (United States)

    Muneepeerakul, Chitsomanus P.; Muneepeerakul, Rachata; Huffaker, Ray G.


    With minimal moral hazard and adverse selection, weather index insurance promises financial resilience to farmers struck by harsh weather conditions through swift compensation at affordable premium. Despite these advantages, the very nature of indexing gives rise to production basis risk as the selected weather indexes do not sufficiently correspond to actual damages. To address this problem, we develop a stochastic yield model, built upon a stochastic soil moisture model driven by marked Poisson rainfall. Our analysis shows that even under similar temperature and rainfall amount yields can differ significantly; this was empirically supported by a 2-year field experiment in which rain-fed maize was grown under very similar total rainfall. Here, the year with more intense, less-frequent rainfall produces a better yield—a rare counter evidence to most climate change projections. Through a stochastic yield model, we demonstrate the crucial roles of rainfall intensity and frequency in determining the yield. Importantly, the model allows us to compute rainfall pattern-related basis risk inherent in cumulative rain index insurance. The model results and a case study herein clearly show that total rainfall is a poor indicator of yield, imposing unnecessary production basis risk on farmers and false-positive payouts on insurers. Incorporating rainfall intensity and frequency in the design of rain index insurance can offer farmers better protection, while maintaining the attractive features of the weather index insurance and thus fulfilling its promise of financial resilience.

  11. Cumulative Advantage in the Skill Development of STEM Graduate Students: A Mixed-Methods Study (United States)

    Feldon, David F.; Maher, Michelle A.; Roksa, Josipa; Peugh, James


    Studies of skill development often describe a process of cumulative advantage, in which small differences in initial skill compound over time, leading to increasing skill gaps between those with an initial advantage and those without. We offer evidence of a similar phenomenon accounting for differential patterns of research skill development in…

  12. Theories of learning: models of good practice for evidence-based information skills teaching. (United States)

    Spring, Hannah


    This feature considers models of teaching and learning and how these can be used to support evidence based practice. © 2010 The authors. Health Information and Libraries Journal © 2010 Health Libraries Group.

  13. Original and cumulative prospect theory: a discussion of empirical differences

    NARCIS (Netherlands)

    Wakker, P.P.; Fennema, H.


    This note discusses differences between prospect theory and cumulative prospect theory. It shows that cumulative prospect theory is not merely a formal correction of some theoretical problems in prospect theory, but it also gives different predictions. Experiments are described that favor cumulative

  14. Chapter 19. Cumulative watershed effects and watershed analysis (United States)

    Leslie M. Reid


    Cumulative watershed effects are environmental changes that are affected by more land-use activity and that are influenced by.processes involving the generation or transport.of water. Almost all environmental changes are.cumulative effects, and almost all land-use.activities contribute to cumulative effects

  15. Stagewise pseudo-value regression for time-varying effects on the cumulative incidence

    DEFF Research Database (Denmark)

    Zöller, Daniela; Schmidtmann, Irene; Weinmann, Arndt


    using a pseudo-value approach. For a grid of time points, the possibly unobserved binary event status is replaced by a jackknife pseudo-value based on the Aalen-Johansen method. We combine a stagewise regression technique with the pseudo-value approach to provide variable selection while allowing......In a competing risks setting, the cumulative incidence of an event of interest describes the absolute risk for this event as a function of time. For regression analysis, one can either choose to model all competing events by separate cause-specific hazard models or directly model the association...... between covariates and the cumulative incidence of one of the events. With a suitable link function, direct regression models allow for a straightforward interpretation of covariate effects on the cumulative incidence. In practice, where data can be right-censored, these regression models are implemented...

  16. Economic models and having children: some evidence from Kwahu, Ghana. (United States)

    Oppong, C; Bleek, W


    This discussion outlines briefly some of the main features of economic models of rational decision making with regard to fertility which focus on the perceived costs and benefits of parenthood, noting the findings of several Ghanaian studies which have tried to link changing patterns of costs and benefits involved in kin and conjugal family ties with changes in fertility and parental role expectations. Procreation and its context in a rural Kwahu town of southern Ghana in the early 1970s is then described and illustration is included of how a "cost benefit" analysis of pregnancy termination and child bearing in this society illuminates why, although induced abortion rates appeared high, there was little noticeable shift to much lower fertility values or achievements than those traditionally admired. The data on the families of Ghanaian salary earners indicated the usefulness of an economic approach, with attention given to the allocation of scarce resources through the essentially rational choices of individual parents, continually trying to avoid or alleviate the effects of role strain and conflict. They also illustrate the need for household economists' models to take more sophisticated account of variables such as the openness or closure of the conjugal family in various areas of its operation and the need to treat the degrees of jointness of the conjugal role relationship in different areas as crucial variables. The town of the research is a typical "home town," which means that it constitutes the base from which people depart, either to an urban center where they take up trading or look for other employment, or to a farming settlement where they may spend from a few months to several years clearing new land or harvesting crops. The data from Kwahu reveal that the people are struggling to improve their lot in an uncertain and changing context in which lineage support is not guaranteed, marriage is unstable and children often leave their parents at an early age

  17. Shale Gas Development and Brook Trout: Scaling Best Management Practices to Anticipate Cumulative Effects (United States)

    Smith, David; Snyder, Craig D.; Hitt, Nathaniel P.; Young, John A.; Faulkner, Stephen P.


    Shale gas development may involve trade-offs between energy development and benefits provided by natural ecosystems. However, current best management practices (BMPs) focus on mitigating localized ecological degradation. We review evidence for cumulative effects of natural gas development on brook trout (Salvelinus fontinalis) and conclude that BMPs should account for potential watershed-scale effects in addition to localized influences. The challenge is to develop BMPs in the face of uncertainty in the predicted response of brook trout to landscape-scale disturbance caused by gas extraction. We propose a decision-analysis approach to formulating BMPs in the specific case of relatively undisturbed watersheds where there is consensus to maintain brook trout populations during gas development. The decision analysis was informed by existing empirical models that describe brook trout occupancy responses to landscape disturbance and set bounds on the uncertainty in the predicted responses to shale gas development. The decision analysis showed that a high efficiency of gas development (e.g., 1 well pad per square mile and 7 acres per pad) was critical to achieving a win-win solution characterized by maintaining brook trout and maximizing extraction of available gas. This finding was invariant to uncertainty in predicted response of brook trout to watershed-level disturbance. However, as the efficiency of gas development decreased, the optimal BMP depended on the predicted response, and there was considerable potential value in discriminating among predictive models through adaptive management or research. The proposed decision-analysis framework provides an opportunity to anticipate the cumulative effects of shale gas development, account for uncertainty, and inform management decisions at the appropriate spatial scales.

  18. Cumulative Environmental Management Association : Wood Buffalo Region

    International Nuclear Information System (INIS)

    Friesen, B.


    The recently announced oil sands development of the Wood Buffalo Region in Alberta was the focus of this power point presentation. Both mining and in situ development is expected to total $26 billion and 2.6 million barrels per day of bitumen production. This paper described the economic, social and environmental challenges facing the resource development of this region. In addition to the proposed oil sands projects, this region will accommodate the needs of conventional oil and gas production, forestry, building of pipelines and power lines, municipal development, recreation, tourism, mining exploration and open cast mining. The Cumulative Environmental Management Association (CEMA) was inaugurated as a non-profit association in April 2000, and includes 41 members from all sectors. Its major role is to ensure a sustainable ecosystem and to avoid any cumulative impacts on wildlife. Other work underway includes the study of soil and plant species diversity, and the effects of air emissions on human health, wildlife and vegetation. The bioaccumulation of heavy metals and their impacts on surface water and fish is also under consideration to ensure the quality and quantity of surface water and ground water. 3 figs

  19. Financial power laws: Empirical evidence, models, and mechanisms

    International Nuclear Information System (INIS)

    Lux, Thomas; Alfarano, Simone


    Financial markets (share markets, foreign exchange markets and others) are all characterized by a number of universal power laws. The most prominent example is the ubiquitous finding of a robust, approximately cubic power law characterizing the distribution of large returns. A similarly robust feature is long-range dependence in volatility (i.e., hyperbolic decline of its autocorrelation function). The recent literature adds temporal scaling of trading volume and multi-scaling of higher moments of returns. Increasing awareness of these properties has recently spurred attempts at theoretical explanations of the emergence of these key characteristics form the market process. In principle, different types of dynamic processes could be responsible for these power-laws. Examples to be found in the economics literature include multiplicative stochastic processes as well as dynamic processes with multiple equilibria. Though both types of dynamics are characterized by intermittent behavior which occasionally generates large bursts of activity, they can be based on fundamentally different perceptions of the trading process. The present paper reviews both the analytical background of the power laws emerging from the above data generating mechanisms as well as pertinent models proposed in the economics literature.

  20. Maternal distress and parenting in the context of cumulative disadvantage. (United States)

    Arditti, Joyce; Burton, Linda; Neeves-Botelho, Sara


    This article presents an emergent conceptual model of the features and links between cumulative disadvantage, maternal distress, and parenting practices in low-income families in which parental incarceration has occurred. The model emerged from the integration of extant conceptual and empirical research with grounded theory analysis of longitudinal ethnographic data from Welfare, Children, and Families: A Three-City Study. Fourteen exemplar family cases were used in the analysis. Results indicated that mothers in these families experienced life in the context of cumulative disadvantage, reporting a cascade of difficulties characterized by neighborhood worries, provider concerns, bureaucratic difficulties, violent intimate relationships, and the inability to meet children's needs. Mothers, however, also had an intense desire to protect their children, and to make up for past mistakes. Although, in response to high levels of maternal distress and disadvantage, most mothers exhibited harsh discipline of their children, some mothers transformed their distress by advocating for their children under difficult circumstances. Women's use of harsh discipline and advocacy was not necessarily an "either/or" phenomenon as half of the mothers included in our analysis exhibited both harsh discipline and care/advocacy behaviors. Maternal distress characterized by substance use, while connected to harsh disciplinary behavior, did not preclude mothers engaging in positive parenting behaviors.

  1. Cumulative abuse: do things add up? An evaluation of the conceptualization, operationalization, and methodological approaches in the study of the phenomenon of cumulative abuse. (United States)

    Scott-Storey, Kelly


    For women, any one type of abuse rarely occurs in isolation of other types, and a single abusive experience is often the exception rather than the norm. The importance of this concept of the cumulative nature of abuse and its negative impact on health has been well recognized within the empirical literature, however there has been little consensus on what to call this phenomenon or how to study it. For the most part researchers have operated on the premise that it is the sheer number of different types of cumulating abuse experiences that is primarily responsible for worse health outcomes among women. And although this simplistic 'more is worse' approach to conceptualizing and operationalizing cumulative abuse has proven to be a powerful predictor of poorer health, it contradicts growing empirical evidence that suggests not all victimizations are created equal and that some victimizations may have a more deleterious effect on health than others. Embedded in abuse histories are individual and abuse characteristics as well as other life adversities that need to be considered in order to fully understand the spectrum and magnitude of cumulative abuse and its impact on women's health. Furthermore, given the long-term and persistent effects of abuse on health it becomes imperative to not only evaluate recent abusive experiences, but rather all abuse experiences occurring across the lifespan. This review highlights and evaluates the conceptual, operational, and methodological challenges posed by our current methods of studying and understanding the phenomenon of cumulative abuse and suggests that this phenomenon and its relationship to health is much more complex than research is currently portraying. This paper calls for the urgent need for interdisciplinary collaboration in order to more effectively and innovatively study the phenomenon of cumulative abuse.

  2. Bayesian evidences for dark energy models in light of current observational data (United States)

    Lonappan, Anto. I.; Kumar, Sumit; Ruchika; Dinda, Bikash R.; Sen, Anjan A.


    We do a comprehensive study of the Bayesian evidences for a large number of dark energy models using a combination of latest cosmological data from SNIa, CMB, BAO, strong lensing time delay, growth measurements, measurements of Hubble parameter at different redshifts and measurements of angular diameter distance by Megamaser Cosmology Project. We consider a variety of scalar field models with different potentials as well as different parametrizations for the dark energy equation of state. Among 21 models that we consider in our study, we do not find strong evidences in favor of any evolving dark energy model compared to Λ CDM . For the evolving dark energy models, we show that purely nonphantom models have much better evidences compared to those models that allow both phantom and nonphantom behaviors. Canonical scalar field with exponential and tachyon field with square potential have highest evidences among all the models considered in this work. We also show that a combination of low redshift measurements decisively favors an accelerating Λ CDM model compared to a nonaccelerating power law model.

  3. Introducing the model of cognitive-communication competence: A model to guide evidence-based communication interventions after brain injury. (United States)

    MacDonald, Sheila


    Communication impairments associated with acquired brain injury (ABI) are devastating in their impact on family, community, social, academic, and vocational participation. Despite international evidence-based guidelines for communication interventions, evidence practice gaps include under identification of communication deficits, infrequent referrals, and inadequate treatment to realize functional communication outcomes. Evidence-informed communication intervention requires synthesis of abundant interdisciplinary research. This study describes the development of the model of cognitive-communication competence, a new model that summarizes a complex array of influences on communication to provide a holistic view of communication competence after ABI. A knowledge synthesis approach was employed to integrate interdisciplinary evidence relevant to communication competence. Development of the model included review of the incidence of communication impairments, practice guidelines, and factors relevant to communication competence guided by three key questions. This was followed by expert consultation with researchers, clinicians, and individuals with ABI. The resulting model comprises 7 domains, 7 competencies, and 47 factors related to communication functioning and intervention. This model could bridge evidence to practice by promoting a comprehensive and consistent view of communication competence for evidence synthesis, clinical decision-making, outcome measurement, and interprofessional collaboration.

  4. Ion cumulation by conical cathode electrolysis.

    CERN Document Server

    Grishin, V G


    Results of solid-state sodium stearate electrolysis with conical and cylindrical cathodes is presented here. Both electric measurement and conical samples destruction can be explained if a stress developing inside the conical sample is much bigger than in the cylindrical case and there is its unlimited amplification along cone slopes. OTHER KEYWORDS: ion, current, solid, symmetry, cumulation, polarization, depolarization, ionic conductor,superionic conductor, ice, crystal, strain, V-center, V-centre, doped crystal, interstitial impurity, intrinsic color center, high pressure technology, Bridgman, anvil, experiment, crowdion, dielectric, proton, layer, defect, lattice, dynamics, electromigration, mobility, muon catalysis, concentration, doping, dopant, conductivity, pycnonuclear reaction, permittivity, dielectric constant, point defects, interstitials, polarizability, imperfection, defect centers, glass, epitaxy, sodium hydroxide, metallic substrate, crystallization, point, tip, susceptibility, ferroelectric, ...

  5. Cumulative receipt of an anti-poverty tax credit for families did not impact tobacco smoking among parents. (United States)

    Pega, Frank; Gilsanz, Paola; Kawachi, Ichiro; Wilson, Nick; Blakely, Tony


    The effect of anti-poverty tax credit interventions on tobacco consumption is unclear. Previous studies have estimated short-term effects, did not isolate the effects of cumulative dose of tax credits, produced conflicting results, and used methods with limited control for some time-varying confounders (e.g., those affected by prior treatment) and treatment regimen (i.e., study participants' tax credit receipt pattern over time). We estimated the longer-term, cumulative effect of New Zealand's Family Tax Credit (FTC) on tobacco consumption, using a natural experiment (administrative errors leading to exogenous variation in FTC receipt) and methods specifically for controlling confounding, reverse causation, and treatment regimen. We extracted seven waves (2002-2009) of the nationally representative Survey of Family, Income and Employment including 4404 working-age (18-65 years) parents in families. The exposure was the total numbers of years of receiving FTC. The outcomes were regular smoking and the average daily number of cigarettes usually smoked at wave 7. We estimated average treatment effects using inverse probability of treatment weighting and marginal structural modelling. Each additional year of receiving FTC affected neither the odds of regular tobacco smoking among all parents (odds ratio 1.02, 95% confidence interval 0.94-1.11), nor the number of cigarettes smoked among parents who smoked regularly (rate ratio 1.01, 95% confidence interval 0.99-1.03). We found no evidence for an association between the cumulative number of years of receiving an anti-poverty tax credit and tobacco smoking or consumption among parents. The assumptions of marginal structural modelling are quite demanding, and we therefore cannot rule out residual confounding. Nonetheless, our results suggest that tax credit programme participation will not increase tobacco consumption among poor parents, at least in this high-income country. Copyright © 2017 Elsevier Ltd. All rights

  6. Bayesian model selection: Evidence estimation based on DREAM simulation and bridge sampling (United States)

    Volpi, Elena; Schoups, Gerrit; Firmani, Giovanni; Vrugt, Jasper A.


    Bayesian inference has found widespread application in Earth and Environmental Systems Modeling, providing an effective tool for prediction, data assimilation, parameter estimation, uncertainty analysis and hypothesis testing. Under multiple competing hypotheses, the Bayesian approach also provides an attractive alternative to traditional information criteria (e.g. AIC, BIC) for model selection. The key variable for Bayesian model selection is the evidence (or marginal likelihood) that is the normalizing constant in the denominator of Bayes theorem; while it is fundamental for model selection, the evidence is not required for Bayesian inference. It is computed for each hypothesis (model) by averaging the likelihood function over the prior parameter distribution, rather than maximizing it as by information criteria; the larger a model evidence the more support it receives among a collection of hypothesis as the simulated values assign relatively high probability density to the observed data. Hence, the evidence naturally acts as an Occam's razor, preferring simpler and more constrained models against the selection of over-fitted ones by information criteria that incorporate only the likelihood maximum. Since it is not particularly easy to estimate the evidence in practice, Bayesian model selection via the marginal likelihood has not yet found mainstream use. We illustrate here the properties of a new estimator of the Bayesian model evidence, which provides robust and unbiased estimates of the marginal likelihood; the method is coined Gaussian Mixture Importance Sampling (GMIS). GMIS uses multidimensional numerical integration of the posterior parameter distribution via bridge sampling (a generalization of importance sampling) of a mixture distribution fitted to samples of the posterior distribution derived from the DREAM algorithm (Vrugt et al., 2008; 2009). Some illustrative examples are presented to show the robustness and superiority of the GMIS estimator with

  7. A Best-Evidence Synthesis of Research on Orientation and Mobility Involving Tactile Maps and Models (United States)

    Wright, Tessa; Harris, Beth; Sticken, Eric


    A review of the literature from 1965 to 2008 on tactile maps and models in orientation and mobility yielded four pre-experimental and three experimental articles. The articles were analyzed via best-evidence synthesis--a combined narrative and statistical approach--allowing for recommendations for the most effective use of tactile maps and models.…

  8. Eating Competence: Definition and Evidence for the Satter Eating Competence Model (United States)

    Satter, Ellyn


    The evidence- and practice-based Satter Eating Competence Model (ecSatter) outlines an inclusive definition of the interrelated spectrum of eating attitudes and behaviors. The model is predicated on the utility and effectiveness of biopsychosocial processes: hunger and the drive to survive, appetite and the need for subjective reward and the…

  9. Bashing Positivism and Reversing a Medical Model under the Guise of Evidence (United States)

    Wampold, Bruce E.


    In her advocacy of a model to train counseling psychologists as "evidence-based practitioners," Chwalisz (2003) (this issue) criticizes research based on positivism and advocates for methodological pluralism but ironically suggests the adoption of a medical model to influence the discourse on practice. In this comment, the author examines (a)…

  10. Ultrasonic assessment of cumulative internal damage in filled polymers (II)

    International Nuclear Information System (INIS)

    Knollman, G.C.; Martinson, R.H.; Bellin, J.L.


    An ultrasonic technique previously developed for studying dewetting and cumulative internal damage in filled polymers, such as solid rocket propellents, has been improved. The previous theoretical treatment is here expanded to include internal vacuoles of general spheroidal (rather than spherical) shape. Experimental measurements of sound speed and attenuation in a solid propellant material are utilized together with the modified theoretical model to calculate the internal damage parameters of effective vacuole size and number density as functions of applied uniaxial tensile strain. Results obtained from the model near the point of material failure are in excellent agreement with those provided by independent microscopic observations made on several rupture surfaces of propellant samples stressed to failure

  11. Cumulative protons in 12C fragmentation at intermediate energy

    International Nuclear Information System (INIS)

    Abramov, B.M.; Alekseev, P.N.; Borodin, Y.A.; Bulychjov, S.A.; Dukhovskoi, I.A.; Khanov, A.I.; Krutenkova, A.P.; Kulikov, V.V.; Martemianov, M.A.; Matsuk, M.A.; Turdakina, E.N.


    In the FRAGM experiment at heavy ion accelerator complex TWAC-ITEP, the proton yields at an angle 3.5 degrees have been measured in fragmentation of carbon ions at T 0 equals 0.3, 0.6, 0.95 and 2.0 GeV/nucleon on beryllium target. The data are presented as invariant proton yields on cumulative variable x in the range 0.9 < x < 2.4. Proton spectra cover six orders of invariant cross section magnitude. They have been analyzed in the framework of quark cluster fragmentation model. Fragmentation functions of quark- gluon string model are used. The probabilities of the existence of multi-quark clusters in carbon nuclei are estimated to be 8 - 12% for six-quark clusters and 0.2 - 0.6% for nine- quark clusters. (authors)

  12. Cumulative dietary exposure of the population of Denmark to pesticides

    DEFF Research Database (Denmark)

    Jensen, Bodil Hamborg; Petersen, Annette; Nielsen, Elsa


    We used the Hazard Index (HI) method to carry out a cumulative risk assessment after chronic dietary exposure to all monitored pesticides in fruit, vegetables and cereals for various consumer groups in Denmark. Residue data for all the pesticides were obtained from the Danish monitoring programme...... during the period 2004e2011. Food consumption data were obtained from DANSDA (the DAnish National Survey of Diet and physical Activity) for the period 2005e2008. The calculations were made using three different models to cope with residues below the limit of reporting (LOR). We concluded that a model...... exposure to the pesticides found in fruit, vegetables and cereals on the Danish market. The HI was below 1 even for consumers who eat more than 550 g of fruit and vegetables per day, corresponding to 1/3 of the population. Choosing Danish-produced commodities whenever possible could reduce the HI...


    Directory of Open Access Journals (Sweden)

    Adam K. Kiss


    Full Text Available The aim of this study is to create a mechanical model which is suitable to investigate the surface quality in turning processes, based on the Cumulative Surface Location Error (CSLE, which describes the series of the consecutive Surface Location Errors (SLE in roughing operations. In the established model, the investigated CSLE depends on the currently and the previously resulted SLE by means of the variation of the width of cut. The phenomenon of the system can be described as an implicit discrete map. The stationary Surface Location Error and its bifurcations were analysed and flip-type bifurcation was observed for CSLE. Experimental verification of the theoretical results was carried out.

  14. Cumulative effects of road de-icing salt on amphibian behavior. (United States)

    Denoël, Mathieu; Bichot, Marion; Ficetola, Gentile Francesco; Delcourt, Johann; Ylieff, Marc; Kestemont, Patrick; Poncin, Pascal


    Despite growing evidence of the detrimental effect of chemical substances on organisms, limited research has focused on changes in behavioral patterns, in part due to the difficulties to obtain detailed quantitative data. Recent developments in efficient computer-based video analyses have allowed testing pesticide effects on model species such as the zebrafish. However, these new techniques have not yet been applied to amphibians and directly to conservation issues, i.e., to assess toxicological risks on threatened species. We used video-tracking analyses to test a quantitative effect of an environmental contaminant on the locomotion of amphibian tadpoles (Rana temporaria) by taking into account cumulative effects. Because recent research has demonstrated effects of de-icing salts on survival and community structure, we used sodium chloride in our experimental design (25 replicates, 4 concentrations, 4 times) to test for an effect at the scale of behavior at environmentally relevant concentrations. Analysis of 372 1-h video-tracks (5 samples/s) showed a complex action of salts on behavioral patterns with a dose and cumulative response over time. Although no effects were found on mortality or growth, the highest salt concentrations reduced the speed and movement of tadpoles in comparison with control treatments. The reduced locomotor performance could have detrimental consequences in terms of tadpoles' responses to competition and predation and may be an indicator of the low concentration effect of the contaminant. On one hand, this study demonstrates the usefulness of examining behavior to address conservation issues and understand the complex action of environmental factors and, more particularly, pollutants on organisms. On the other hand, our results highlight the need of new computerized techniques to quantitatively analyze these patterns. (c) 2010 Elsevier B.V. All rights reserved.

  15. Cumulative trauma, gender discrimination and mental health in women: mediating role of self-esteem. (United States)

    Kucharska, Justyna


    Evidence suggests that women show symptoms of trauma-related symptoms more often than men. Gender discrimination is also associated with the severity of symptoms in women. This study explored the relations among cumulative trauma, gender discrimination and mental health in women with a mediating role of self-esteem and emotion regulation. Two types of gender discrimination were taken into account: discrimination by parents and in the social context. Cumulative trauma over the lifetime was assessed, as well as three types of symptoms: internalising, externalising, psychoticism. A total of 277 females from Poland participated in the study. It was hypothesised that gender discrimination and cumulative trauma would be positively related to symptoms and that lowered self-esteem mediates these relations. Hypotheses received partial confirmation, as both gender discrimination and cumulative trauma have been shown to be related to three types of symptoms. Self-esteem was a partial mediator between gender discrimination in the social context and symptoms. It was also demonstrated that emotion suppression is a partial mediator between cumulative trauma and symptoms. It has been demonstrated that socio-cultural factors, such as gender discrimination, play an important role in psychiatric symptoms development.

  16. Incorporating cumulative effects into environmental assessments of mariculture: Limitations and failures of current siting methods

    International Nuclear Information System (INIS)

    King, Sarah C.; Pushchak, Ronald


    Assessing and evaluating the cumulative impacts of multiple marine aquaculture facilities has proved difficult in environmental assessment. A retrospective review of 23 existing mariculture farms in southwestern New Brunswick was conducted to determine whether cumulative interactions would have justified site approvals. Based on current scientific evidence of cumulative effects, six new criteria were added to a set of far-field impacts and other existing criteria were expanded to include regional and cumulative environmental impacts in Hargrave's [Hargrave BT. A traffic light decision system for marine finfish aquaculture siting. Ocean Coast Manag 2002; 45:215-35.] Traffic Light Decision Support System (DSS) presently used in Canadian aquaculture environmental assessments. Before mitigation, 19 of the 23 sites failed the amended set of criteria and after considering mitigation, 8 sites failed. Site and ecosystem indices yielded varying site acceptability scores; however, many sites would not have been approved if siting decisions had been made within a regional management framework and cumulative impact criteria were considered in the site evaluation process

  17. Automated Eukaryotic Gene Structure Annotation Using EVidenceModeler and the Program to Assemble Spliced Alignments

    Energy Technology Data Exchange (ETDEWEB)

    Haas, B J; Salzberg, S L; Zhu, W; Pertea, M; Allen, J E; Orvis, J; White, O; Buell, C R; Wortman, J R


    EVidenceModeler (EVM) is presented as an automated eukaryotic gene structure annotation tool that reports eukaryotic gene structures as a weighted consensus of all available evidence. EVM, when combined with the Program to Assemble Spliced Alignments (PASA), yields a comprehensive, configurable annotation system that predicts protein-coding genes and alternatively spliced isoforms. Our experiments on both rice and human genome sequences demonstrate that EVM produces automated gene structure annotation approaching the quality of manual curation.

  18. The evidence-based medicine model of clinical practice: scientific teaching or belief-based preaching? (United States)

    Charles, Cathy; Gafni, Amiram; Freeman, Emily


    Evidence-based medicine (EBM) is commonly advocated as a 'gold standard' of clinical practice. A prominent definition of EBM is: the integration of best research evidence with clinical expertise and patient values. Over time, various versions of a conceptual model or framework for implementing EBM (i.e. how to practice EBM) have been developed. This paper (i) traces the evolution of the different versions of the conceptual model; (ii) tries to make explicit the underlying goals, assumptions and logic of the various versions by exploring the definitions and meaning of the components identified in each model, and the methods suggested for integrating these into clinical practice; and (iii) offers an analytic critique of the various model iterations. A literature review was undertaken to identify, summarize, and compare the content of articles and books discussing EBM as a conceptual model to guide physicians in clinical practice. Our findings suggest that the EBM model of clinical practice, as it has evolved over time, is largely belief-based, because it is lacking in empirical evidence and theoretical support. The model is not well developed and articulated in terms of defining model components, justifying their inclusion and suggesting ways to integrate these in clinical practice. These findings are significant because without a model that clearly defines what constitutes an EBM approach to clinical practice we cannot (i) consistently teach clinicians how to do it and (ii) evaluate whether it is being done. © 2010 Blackwell Publishing Ltd.

  19. Probabilistic cumulative risk assessment of anti-androgenic pesticides in food

    DEFF Research Database (Denmark)

    Müller, Anne Kirstine; Bosgra, Sieto; Boon, Polly E.


    In this paper, we present a cumulative risk assessment of three anti-androgenic pesticides (vinclozolin, procymidone and prochloraz) using the relative potency factor (RPF) approach and an integrated probabilistic risk assessment (IPRA) model. RPFs for each substance were estimated for three...... reproductive endpoints (ano-genital distance, and weights of the seminal vesicles and the musculus levator ani/bulbocavernosus) in male rat foetuses exposed in utero. The cumulative dietary intake was estimated based on consumption data and residue data from the Netherlands. The IPRA model combines variability...


    Directory of Open Access Journals (Sweden)

    P. Li


    Full Text Available This paper proposed a novel method of decision fusion based on weights of evidence model (WOE. The probability rules from classification results from each separate dataset were fused using WOE to produce the posterior probability for each class. The final classification was obtained by maximum probability. The proposed method was evaluated in land cover classification using two examples. The results showed that the proposed method effectively combined multisensor data in land cover classification and obtained higher classification accuracy than the use of single source data. The weights of evidence model provides an effective decision fusion method for improved land cover classification using multi-sensor data.

  1. Ecological plant epigenetics : Evidence from model and non-model species, and the way forward

    NARCIS (Netherlands)

    Richards, Christina L.; Alonso, Conchita; Becker, Claude; Bossdorf, Oliver; Bucher, Etienne; Colomé-Tatché, Maria; Durka, Walter; Engelhardt, Jan; Gaspar, Bence; Gogol-Doering, Andreas; Grosse, Ivo; van Gurp, Thomas P.; Heer, Katrin; Kronholm, Ilkka; Lampei, Christian; Latzel, Vit; Mirouze, Marie; Opgenoorth, Lars; Paun, Ovidiu; Prohaska, Sonja J.; Rensing, Stefan A.; Stadler, Peter F.; Trucchi, Emiliano; Ullrich, Kristian; Verhoeven, Koen J. F.


    Growing evidence shows that epigenetic mechanisms contribute to complex traits, with implications across many fields of biology. In plant ecology, recent studies have attempted to merge ecological experiments with epigenetic analyses to elucidate the contribution of epigenetics to plant phenotypes,

  2. Probabilistic cumulative risk assessment of anti-androgenic pesticides in food

    DEFF Research Database (Denmark)

    Müller, Anne Kirstine; Nielsen, Elsa


    A cumulative risk assessment of three anti-androgenic pesticides vinclozolin, procymidone and prochloraz in combination has been carried out using an Integrated Probabilistic Risk Assessment (IPRA) model. In the model, variability in both exposure and sensitivity between individuals were combined...... into a distribution of Individual Margins of Exposure (IMoE). Additionally, uncertainties related to input parameters were evaluated. The cumulative risk assessment was performed using the Relative Potency Factor (RPF) approach. RPFs for each substance were estimated for three reproductive endpoints in male foetuses...... as observed following in utero exposure in rats (ano-genital distance, and weight of the seminal vesicles and the levator ani/bulbocavernosus (LABC) muscles). The estimations of the cumulative dietary intake were based on consumption data (1997–1998) and residue data (2002–2003) from the Netherlands. Inter...

  3. Meaning and magnitude of the reduced density matrix cumulants (United States)

    Hanauer, Matthias; Köhn, Andreas


    Within the framework of a generalized normal ordering (GNO), invented by Mukherjee [1], the reduced density matrix cumulants of the (multiconfigurational) reference wave function play a central role, as they arise directly from the contraction rules. The extended Wick theorem allows contractions of an arbitrary number of active annihilators and creators through a cumulant of corresponding rank. Because the cumulant rank truncates naturally only at the number of active spin orbitals, practical applications of the GNO concept seem to rely on a fast convergence of the cumulant series, allowing one to neglect cumulants with high rank. By computing cumulant norms for selected systems (and up to rank 16), we demonstrate that the cumulants decay approximately exponentially with increasing rank for single reference cases, while the convergence is generally slower for multireference cases. When strong left-right correlation is present as in the singlet state of a dissociated N2 molecule, even the cumulant with maximum rank, λ12 ≈ -1.5 for a CAS(6, 6), is not negligible per se. Besides reporting numerical results, the authors reformulate the theory of reduced density matrices and their cumulants using a notation that is particularly easy to handle, highlighting the close connection to conventional statistics. From this statistical approach, a simple interpretation of reduced density matrices and cumulants follows, according to which an n-body cumulant is a measure for the correlation between the occupation numbers of n spin orbitals. This interpretation is also valid for cumulants with ranks exceeding the number of electrons in the system.

  4. 7 CFR 42.132 - Determining cumulative sum values. (United States)


    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Determining cumulative sum values. 42.132 Section 42... Determining cumulative sum values. (a) The parameters for the on-line cumulative sum sampling plans for AQL's... 3 1 2.5 3 1 2 1 (b) At the beginning of the basic inspection period, the CuSum value is set equal to...

  5. Improving cumulative effects assessment in Alberta: Regional strategic assessment

    International Nuclear Information System (INIS)

    Johnson, Dallas; Lalonde, Kim; McEachern, Menzie; Kenney, John; Mendoza, Gustavo; Buffin, Andrew; Rich, Kate


    The Government of Alberta, Canada is developing a regulatory framework to better manage cumulative environmental effects from development in the province. A key component of this effort is regional planning, which will lay the primary foundation for cumulative effects management into the future. Alberta Environment has considered the information needs of regional planning and has concluded that Regional Strategic Assessment may offer significant advantages if integrated into the planning process, including the overall improvement of cumulative environmental effects assessment in the province.

  6. Standardization of the cumulative absolute velocity

    International Nuclear Information System (INIS)

    O'Hara, T.F.; Jacobson, J.P.


    EPRI NP-5930, ''A Criterion for Determining Exceedance of the Operating Basis Earthquake,'' was published in July 1988. As defined in that report, the Operating Basis Earthquake (OBE) is exceeded when both a response spectrum parameter and a second damage parameter, referred to as the Cumulative Absolute Velocity (CAV), are exceeded. In the review process of the above report, it was noted that the calculation of CAV could be confounded by time history records of long duration containing low (nondamaging) acceleration. Therefore, it is necessary to standardize the method of calculating CAV to account for record length. This standardized methodology allows consistent comparisons between future CAV calculations and the adjusted CAV threshold value based upon applying the standardized methodology to the data set presented in EPRI NP-5930. The recommended method to standardize the CAV calculation is to window its calculation on a second-by-second basis for a given time history. If the absolute acceleration exceeds 0.025g at any time during each one second interval, the earthquake records used in EPRI NP-5930 have been reanalyzed and the adjusted threshold of damage for CAV was found to be 0.16g-set

  7. Children neglected: Where cumulative risk theory fails. (United States)

    O'Hara, Mandy; Legano, Lori; Homel, Peter; Walker-Descartes, Ingrid; Rojas, Mary; Laraque, Danielle


    Neglected children, by far the majority of children maltreated, experience an environment most deficient in cognitive stimulation and language exchange. When physical abuse co-occurs with neglect, there is more stimulation through negative parent-child interaction, which may lead to better cognitive outcomes, contrary to Cumulative Risk Theory. The purpose of the current study was to assess whether children only neglected perform worse on cognitive tasks than children neglected and physically abused. Utilizing LONGSCAN archived data, 271 children only neglected and 101 children neglected and physically abused in the first four years of life were compared. The two groups were assessed at age 6 on the WPPSI-R vocabulary and block design subtests, correlates of cognitive intelligence. Regression analyses were performed, controlling for additional predictors of poor cognitive outcome, including socioeconomic variables and caregiver depression. Children only neglected scored significantly worse than children neglected and abused on the WPPSI-R vocabulary subtest (p=0.03). The groups did not differ on the block design subtest (p=0.4). This study shows that for neglected children, additional abuse may not additively accumulate risk when considering intelligence outcomes. Children experiencing only neglect may need to be referred for services that address cognitive development, with emphasis on the linguistic environment, in order to best support the developmental challenges of neglected children. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Implantable magnetic relaxation sensors measure cumulative exposure to cardiac biomarkers. (United States)

    Ling, Yibo; Pong, Terrence; Vassiliou, Christophoros C; Huang, Paul L; Cima, Michael J


    Molecular biomarkers can be used as objective indicators of pathologic processes. Although their levels often change over time, their measurement is often constrained to a single time point. Cumulative biomarker exposure would provide a fundamentally different kind of measurement to what is available in the clinic. Magnetic resonance relaxometry can be used to noninvasively monitor changes in the relaxation properties of antibody-coated magnetic particles when they aggregate upon exposure to a biomarker of interest. We used implantable devices containing such sensors to continuously profile changes in three clinically relevant cardiac biomarkers at physiological levels for up to 72 h. Sensor response differed between experimental and control groups in a mouse model of myocardial infarction and correlated with infarct size. Our prototype for a biomarker monitoring device also detected doxorubicin-induced cardiotoxicity and can be adapted to detect other molecular biomarkers with a sensitivity as low as the pg/ml range.

  9. Proposal of a holistic model to support local-level evidence-based practice. (United States)

    Shahtahmasebi, Said; Villa, Luis; Nielsen, Helen; Graham-Smith, Hilary


    In response to a central drive for evidence-based practice, there have been many research support schemes, setups, and other practices concentrating on facilitating access to external research, such as the Centre for Evidence Based Healthcare Aotearoa, the Cochrane Collaboration, and the York Centre for Reviews and Dissemination. Very little attention has been paid to supporting internal research in terms of local evidence and internal research capabilities. The whole evidence-based practice movement has alienated internal decision makers and, thus, very little progress has been made in the context of evidence informing local policy formation. Health and social policies are made centrally based on dubious claims and often evidence is sought after implementation. For example, on record, most health care practitioners appear to agree with the causal link between depression and mental illness (sometimes qualified with other social factors) with suicide; off the record, even some psychiatrists doubt that such a link is applicable to the population as a whole. Therefore, be it through misplaced loyalty or a lack of support for internal researchers/decision makers, local evidence informing local decision making may have been ignored in favour of external evidence. In this paper, we present a practical holistic model to support local evidence-based decision making. This approach is more relevant in light of a new approach to primary health care of "local knowledge" complementing external evidence. One possible outcome would be to network with other regional programmes around the world to share information and identify "best" practices, such as the "Stop Youth Suicide Campaign" (

  10. Proposal of a Holistic Model to Support Local-Level Evidence-Based Practice

    Directory of Open Access Journals (Sweden)

    Said Shahtahmasebi


    Full Text Available In response to a central drive for evidence-based practice, there have been many research support schemes, setups, and other practices concentrating on facilitating access to external research, such as the Centre for Evidence Based Healthcare Aotearoa, the Cochrane Collaboration, and the York Centre for Reviews and Dissemination. Very little attention has been paid to supporting internal research in terms of local evidence and internal research capabilities. The whole evidence-based practice movement has alienated internal decision makers and, thus, very little progress has been made in the context of evidence informing local policy formation. Health and social policies are made centrally based on dubious claims and often evidence is sought after implementation. For example, on record, most health care practitioners appear to agree with the causal link between depression and mental illness (sometimes qualified with other social factors with suicide; off the record, even some psychiatrists doubt that such a link is applicable to the population as a whole. Therefore, be it through misplaced loyalty or a lack of support for internal researchers/decision makers, local evidence informing local decision making may have been ignored in favour of external evidence. In this paper, we present a practical holistic model to support local evidence-based decision making. This approach is more relevant in light of a new approach to primary health care of “local knowledge” complementing external evidence. One possible outcome would be to network with other regional programmes around the world to share information and identify “best” practices, such as the “Stop Youth Suicide Campaign”(

  11. Theory- and Evidence- Based Intervention: Practice-Based Evidence--Integrating Positive Psychology into a Clinical Psychological Assessment and Intervention Model and How to Measure Outcome (United States)

    Nissen, Poul


    In this paper, a model for assessment and intervention is presented. This model explains how to perform theory- and evidence- based as well as practice-based assessment and intervention. The assessment model applies a holistic approach to treatment planning, which includes recognition of the influence of community, school, peers, family and the…

  12. Study of the Cumulative Number Distribution of Charged Particles Produced in d12C-Interactions at 4.2 A GeV/c (United States)

    Aslam, S. M.; Suleymanov, M. K.; Wazir, Z.; Gilani, A. R.


    In this paper the behavior of the cumulative number and also with maximum values of cumulative number distribution of protons, π + and π --mesons, have been studied, produced in d12C-interctions at 4.2 A GeV/c. The experimental data has been compared with ones coming from the Dubna version of the cascade model. In the analysis we have observed; four different regions in the cumulative number distributions for all charged particle and protons and the last region is corresponding to values of cumulative number greater than 1; for pions number of regions decreased to 2 for π ±-mesons but cumulative area is absent for both mesons. Cascade cannot describe satisfactorily the distributions of the cumulative protons and cumulative π -+-mesons, it gives less number for the all produced particles. In case of particles with maximum values of cumulative number cascade can describe the behavior of cumulative number distribution well. There exist some events with two cumulative particles which could not describe by the cascade dynamics. May be collective nucleon effect could be reasons of the observation two cumulative particles events.

  13. County-level cumulative environmental quality associated with cancer incidence. (United States)

    Jagai, Jyotsna S; Messer, Lynne C; Rappazzo, Kristen M; Gray, Christine L; Grabich, Shannon C; Lobdell, Danelle T


    Individual environmental exposures are associated with cancer development; however, environmental exposures occur simultaneously. The Environmental Quality Index (EQI) is a county-level measure of cumulative environmental exposures that occur in 5 domains. The EQI was linked to county-level annual age-adjusted cancer incidence rates from the Surveillance, Epidemiology, and End Results (SEER) Program state cancer profiles. All-site cancer and the top 3 site-specific cancers for male and female subjects were considered. Incident rate differences (IRDs; annual rate difference per 100,000 persons) and 95% confidence intervals (CIs) were estimated using fixed-slope, random intercept multilevel linear regression models. Associations were assessed with domain-specific indices and analyses were stratified by rural/urban status. Comparing the highest quintile/poorest environmental quality with the lowest quintile/best environmental quality for overall EQI, all-site county-level cancer incidence rate was positively associated with poor environmental quality overall (IRD, 38.55; 95% CI, 29.57-47.53) and for male (IRD, 32.60; 95% CI, 16.28-48.91) and female (IRD, 30.34; 95% CI, 20.47-40.21) subjects, indicating a potential increase in cancer incidence with decreasing environmental quality. Rural/urban stratified models demonstrated positive associations comparing the highest with the lowest quintiles for all strata, except the thinly populated/rural stratum and in the metropolitan/urbanized stratum. Prostate and breast cancer demonstrated the strongest positive associations with poor environmental quality. We observed strong positive associations between the EQI and all-site cancer incidence rates, and associations differed by rural/urban status and environmental domain. Research focusing on single environmental exposures in cancer development may not address the broader environmental context in which cancers develop, and future research should address cumulative environmental

  14. Spatial prediction of landslide susceptibility in parts of Garhwal Himalaya, India, using the weight of evidence modelling. (United States)

    Guri, Pardeep Kumar; Ray, P K Champati; Patel, Ramesh Chandra


    Garhwal Himalaya in northern India has emerged as one of the most prominent hot spots of landslide occurrences in the Himalaya mainly due to geological causes related to mountain building processes, steep topography and frequent occurrences of extreme precipitation events. As this region has many pilgrimage and tourist centres, it is visited by hundreds of thousands of people every year, and in the recent past, there has been rapid development to provide adequate roads and building infrastructure. Additionally, attempts are also made to harness hydropower by constructing tunnels, dams and reservoirs and thus altering vulnerable slopes at many places. As a result, the overall risk due to landslide hazards has increased many folds and, therefore, an attempt was made to assess landslide susceptibility using 'Weights of Evidence (WofE)', a well-known bivariate statistical modelling technique implemented in a much improved way using remote sensing and Geographic Information System. This methodology has dual advantage as it demonstrates how to derive critical parameters related to geology, geomorphology, slope, land use and most importantly temporal landslide distribution in one of the data scarce region of the world. Secondly, it allows to experiment with various combination of parameters to assess their cumulative effect on landslides. In total, 15 parameters related to geology, geomorphology, terrain, hydrology and anthropogenic factors and 2 different landslide inventories (prior to 2007 and 2008-2011) were prepared from high-resolution Indian remote sensing satellite data (Cartosat-1 and Resourcesat-1) and were validated by field investigation. Several combinations of parameters were carried out using WofE modelling, and finally using best combination of eight parameters, 76.5 % of overall landslides were predicted in 24 % of the total area susceptible to landslide occurrences. The study has highlighted that using such methodology landslide susceptibility assessment

  15. Mineral chemistry and petrology of highly magnesian ultramafic cumulates from the Sarve-Abad (Sawlava) ophiolites (Kurdistan, NW Iran): New evidence for boninitic magmatism in intra-oceanic fore-arc setting in the Neo-Tethys between Arabia and Iran (United States)

    Allahyari, Khalil; Saccani, Emilio; Rahimzadeh, Bahman; Zeda, Ottavia


    The Sarve-Abad (Sawlava) ophiolitic complex consists of several tectonically dismembered ophiolitic sequences. They are located along the Main Zagros Thrust Zone, which marks the ophiolitic suture between the Arabian and Sanandaj-Sirjan continental blocks. They represent a portion of the southern Neo-Tethyan oceanic lithosphere, which originally existed between the Arabian (to the south) and Eurasian (to the north) continental margins. The Sarve-Abad ophiolites include cumulitic lherzolites bearing minor dunite and chromitite lenses in places. The main rock-forming minerals in ultramafic cumulates are cumulus olivine and inter-cumulus clinopyroxene and orthopyroxene. Minor (<5%) chromian spinel occurs as both cumulus and inter-cumulus phases.

  16. Revisiting Structural Modeling of Credit Risk—Evidence from the Credit Default Swap (CDS Market

    Directory of Open Access Journals (Sweden)

    Zhijian (James Huang


    Full Text Available The ground-breaking Black-Scholes-Merton model has brought about a generation of derivative pricing models that have been successfully applied in the financial industry. It has been a long standing puzzle that the structural models of credit risk, as an application of the same modeling paradigm, do not perform well empirically. We argue that the ability to accurately compute and dynamically update hedge ratios to facilitate a capital structure arbitrage is a distinctive strength of the Black-Scholes-Merton’s modeling paradigm which could be utilized in credit risk models as well. Our evidence is economically significant: We improve the implementation of a simple structural model so that it is more suitable for our application and then devise a simple capital structure arbitrage strategy based on the model. We show that the trading strategy persistently produced substantial risk-adjusted profit.

  17. Diabetes Mellitus Induces Alzheimer’s Disease Pathology: Histopathological Evidence from Animal Models

    Directory of Open Access Journals (Sweden)

    Nobuyuki Kimura


    Full Text Available Alzheimer’s disease (AD is the major causative disease of dementia and is characterized pathologically by the accumulation of senile plaques (SPs and neurofibrillary tangles (NFTs in the brain. Although genetic studies show that β-amyloid protein (Aβ, the major component of SPs, is the key factor underlying AD pathogenesis, it remains unclear why advanced age often leads to AD. Interestingly, several epidemiological and clinical studies show that type II diabetes mellitus (DM patients are more likely to exhibit increased susceptibility to AD. Moreover, growing evidence suggests that there are several connections between the neuropathology that underlies AD and DM, and there is evidence that the experimental induction of DM can cause cognitive dysfunction, even in rodent animal models. This mini-review summarizes histopathological evidence that DM induces AD pathology in animal models and discusses the possibility that aberrant insulin signaling is a key factor in the induction of AD pathology.

  18. Brief Strategic Family Therapy: Implementing evidence-based models in community settings


    Szapocznik, José; Muir, Joan A.; Duff, Johnathan H.; Schwartz, Seth J.; Brown, C. Hendricks


    Reflecting a nearly 40-year collaborative partnership between clinical researchers and clinicians, the present article reviews the authors’ experience in developing, investigating, and implementing the Brief Strategic Family Therapy (BSFT) model. The first section of the article focuses on the theory, practice, and studies related to this evidence-based family therapy intervention targeting adolescent drug abuse and delinquency. The second section focuses on the implementation model created f...

  19. Experimental evidence for a dual pathway model analysis of coping with the climate crisis

    NARCIS (Netherlands)

    van Zomeren, Martijn; Spears, Russell; Leach, Colinn Wayne


    Two experiments examined the psychological power of fear and group efficacy beliefs to increase environmental action intentions against the climate crisis Extending a dual pathway model of coping with collective disadvantage results showed evidence for emotion-focused approach coping Environmental

  20. Modelling distribution of archaeological settlement evidence based on heterogeneous spatial and temporal data

    Czech Academy of Sciences Publication Activity Database

    Demján, P.; Dreslerová, Dagmar


    Roč. 69, May (2016), s. 100-109 ISSN 0305-4403 Institutional support: RVO:67985912 Keywords : settlement density * evidence density estimation * predictive modelling * prehistory * large datasets Subject RIV: AC - Archeology, Anthropology, Ethnology Impact factor: 2.602, year: 2016

  1. An evidence-based patient-centered method makes the biopsychosocial model scientific. (United States)

    Smith, Robert C; Fortin, Auguste H; Dwamena, Francesca; Frankel, Richard M


    To review the scientific status of the biopsychosocial (BPS) model and to propose a way to improve it. Engel's BPS model added patients' psychological and social health concerns to the highly successful biomedical model. He proposed that the BPS model could make medicine more scientific, but its use in education, clinical care, and, especially, research remains minimal. Many aver correctly that the present model cannot be defined in a consistent way for the individual patient, making it untestable and non-scientific. This stems from not obtaining relevant BPS data systematically, where one interviewer obtains the same information another would. Recent research by two of the authors has produced similar patient-centered interviewing methods that are repeatable and elicit just the relevant patient information needed to define the model at each visit. We propose that the field adopt these evidence-based methods as the standard for identifying the BPS model. Identifying a scientific BPS model in each patient with an agreed-upon, evidence-based patient-centered interviewing method can produce a quantum leap ahead in both research and teaching. A scientific BPS model can give us more confidence in being humanistic. In research, we can conduct more rigorous studies to inform better practices. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  2. Transmission fidelity is the key to the build-up of cumulative culture. (United States)

    Lewis, Hannah M; Laland, Kevin N


    Many animals have socially transmitted behavioural traditions, but human culture appears unique in that it is cumulative, i.e. human cultural traits increase in diversity and complexity over time. It is often suggested that high-fidelity cultural transmission is necessary for cumulative culture to occur through refinement, a process known as 'ratcheting', but this hypothesis has never been formally evaluated. We discuss processes of information transmission and loss of traits from a cognitive viewpoint alongside other cultural processes of novel invention (generation of entirely new traits), modification (refinement of existing traits) and combination (bringing together two established traits to generate a new trait). We develop a simple cultural transmission model that does not assume major evolutionary changes (e.g. in brain architecture) and show that small changes in the fidelity with which information is passed between individuals can lead to cumulative culture. In comparison, modification and combination have a lesser influence on, and novel invention appears unimportant to, the ratcheting process. Our findings support the idea that high-fidelity transmission is the key driver of human cumulative culture, and that progress in cumulative culture depends more on trait combination than novel invention or trait modification.

  3. Data analysis techniques: a tool for cumulative exposure assessment. (United States)

    Lalloué, Benoît; Monnez, Jean-Marie; Padilla, Cindy; Kihal, Wahida; Zmirou-Navier, Denis; Deguen, Séverine


    Everyone is subject to environmental exposures from various sources, with negative health impacts (air, water and soil contamination, noise, etc.or with positive effects (e.g. green space). Studies considering such complex environmental settings in a global manner are rare. We propose to use statistical factor and cluster analyses to create a composite exposure index with a data-driven approach, in view to assess the environmental burden experienced by populations. We illustrate this approach in a large French metropolitan area. The study was carried out in the Great Lyon area (France, 1.2 M inhabitants) at the census Block Group (BG) scale. We used as environmental indicators ambient air NO2 annual concentrations, noise levels and proximity to green spaces, to industrial plants, to polluted sites and to road traffic. They were synthesized using Multiple Factor Analysis (MFA), a data-driven technique without a priori modeling, followed by a Hierarchical Clustering to create BG classes. The first components of the MFA explained, respectively, 30, 14, 11 and 9% of the total variance. Clustering in five classes group: (1) a particular type of large BGs without population; (2) BGs of green residential areas, with less negative exposures than average; (3) BGs of residential areas near midtown; (4) BGs close to industries; and (5) midtown urban BGs, with higher negative exposures than average and less green spaces. Other numbers of classes were tested in order to assess a variety of clustering. We present an approach using statistical factor and cluster analyses techniques, which seem overlooked to assess cumulative exposure in complex environmental settings. Although it cannot be applied directly for risk or health effect assessment, the resulting index can help to identify hot spots of cumulative exposure, to prioritize urban policies or to compare the environmental burden across study areas in an epidemiological framework.

  4. The education of medical librarians in evidence-based information services: a model of active learning

    Directory of Open Access Journals (Sweden)

    Huriye Çolaklar


    Full Text Available Evidence-based practice stems from clinical approaches which are used in the late 18th and early 19th centuries’ medical practices. This area is new in Turkey, too. Turkey needs some lessons about evidence-based practice in Departments of Information and Records Management. This paper, examining the examples in various other countries, presents a model for including the evidence-based information services, which are based on research done in the fields of health and medicine and especially of dentistry, within the contents of the already existing courses in education of librarianship in Turkey. The paper depicts the aims and fields of use of evidence-based information services and their contribution to active learning; examines the education of this subject in various other countries and shows its place in Turkey, and presents a model for the improvement of this education. It is proved that the education of the librarians who will give evidence-based information services both with special practices within the already existing courses or with optional courses given especially for this aim in education of librarianship will contribute considerably to active learning in dentistry.

  5. 42 CFR 457.560 - Cumulative cost-sharing maximum. (United States)


    ... State Plan Requirements: Enrollee Financial Responsibilities § 457.560 Cumulative cost-sharing maximum... similar cost-sharing charges that, in the aggregate, exceed 5 percent of a family's total income for the... 42 Public Health 4 2010-10-01 2010-10-01 false Cumulative cost-sharing maximum. 457.560 Section...

  6. Forest Practice Rules and cumulative watershed impacts in California (United States)

    L. M. Reid


    Response to the following questions, "As currently implemented, are existing California forest practice rules effective in preventing cumulative watershed impacts, including flooding?" and "What kind of measures might improve the effectiveness of forest practices rules for avoiding forestry-related cumulative watershed impacts

  7. Decision making generalized by a cumulative probability weighting function (United States)

    dos Santos, Lindomar Soares; Destefano, Natália; Martinez, Alexandre Souto


    Typical examples of intertemporal decision making involve situations in which individuals must choose between a smaller reward, but more immediate, and a larger one, delivered later. Analogously, probabilistic decision making involves choices between options whose consequences differ in relation to their probability of receiving. In Economics, the expected utility theory (EUT) and the discounted utility theory (DUT) are traditionally accepted normative models for describing, respectively, probabilistic and intertemporal decision making. A large number of experiments confirmed that the linearity assumed by the EUT does not explain some observed behaviors, as nonlinear preference, risk-seeking and loss aversion. That observation led to the development of new theoretical models, called non-expected utility theories (NEUT), which include a nonlinear transformation of the probability scale. An essential feature of the so-called preference function of these theories is that the probabilities are transformed by decision weights by means of a (cumulative) probability weighting function, w(p) . We obtain in this article a generalized function for the probabilistic discount process. This function has as particular cases mathematical forms already consecrated in the literature, including discount models that consider effects of psychophysical perception. We also propose a new generalized function for the functional form of w. The limiting cases of this function encompass some parametric forms already proposed in the literature. Far beyond a mere generalization, our function allows the interpretation of probabilistic decision making theories based on the assumption that individuals behave similarly in the face of probabilities and delays and is supported by phenomenological models.

  8. Estimation of cumulative exposures to naphtha at an automobile fuel-injector manufacturing plant. (United States)

    Rocskay, A Z; Robins, T G; Echeverria, D; Schork, M A; Seixas, N S; White, R F; Proctor, S P


    As part of an epidemiologic study of neuropsychological and renal effects of occupational exposure to organic solvents, estimates of cumulative exposure to naphtha were derived for workers at an automobile fuel-injector manufacturing plant. The approach to exposure estimation was relatively unusual in three respects: (1) a marked association between indoor naphtha air concentration and outdoor temperature was modeled and applied to detailed historical temperature data to calculate cumulative exposure estimates; (2) the large number of investigator-generated air samples allowed the use of analyses of variance to compare alternative job-grouping schemes; and (3) the young age of the plant and few process changes allowed for historical exposure estimates with a high degree of confidence. The derived estimates of cumulative exposure appear to offer a firm basis for epidemiologic analyses of exposure-health outcome relationships.

  9. The Zero Suicide Model: Applying Evidence-Based Suicide Prevention Practices to Clinical Care

    Directory of Open Access Journals (Sweden)

    Beth S. Brodsky


    Full Text Available Suicide is reaching epidemic proportions, with over 44,000 deaths by suicide in the US, and 800,000 worldwide in 2015. This, despite research and development of evidence-based interventions that target suicidal behavior directly. Suicide prevention efforts need a comprehensive approach, and research must lead to effective implementation across public and mental health systems. A 10-year systematic review of evidence-based findings in suicide prevention summarized the areas necessary for translating research into practice. These include risk assessment, means restriction, evidence-based treatments, population screening combined with chain of care, monitoring, and follow-up. In this article, we review how suicide prevention research informs implementation in clinical settings where those most at risk present for care. Evidence-based and best practices address the fluctuating nature of suicide risk, which requires ongoing risk assessment, direct intervention and monitoring. In the US, the National Action Alliance for Suicide Prevention has put forth the Zero Suicide (ZS Model, a framework to coordinate a multilevel approach to implementing evidence-based practices. We present the Assess, Intervene and Monitor for Suicide Prevention model (AIM-SP as a guide for implementation of ZS evidence-based and best practices in clinical settings. Ten basic steps for clinical management model will be described and illustrated through case vignette. These steps are designed to be easily incorporated into standard clinical practice to enhance suicide risk assessment, brief interventions to increase safety and teach coping strategies and to improve ongoing contact and monitoring of high-risk individuals during transitions in care and high risk periods.

  10. Optimization of the cumulative risk assessment of pesticides and biocides using computational techniques: Pilot project

    DEFF Research Database (Denmark)

    Jonsdottir, Svava Osk; Reffstrup, Trine Klein; Petersen, Annette

    This pilot project is intended as the first step in developing a computational strategy to assist in refining methods for higher tier cumulative and aggregate risk assessment of exposure to mixture of pesticides and biocides. For this purpose, physiologically based toxicokinetic (PBTK) models were...

  11. Evaluation of Cumulative Ecosystem Response to Restoration Projects in the Lower Columbia River and Estuary, 2010 (United States)


    target Realized residence Electronic tags Cumulative hours, mean Mark/recapture Increase residence Salmon wetland utilization Use of...information available since 2004. The model (Thom et al. 2004) brings together into one easily navigated electronic tool the information provided lca Natural Resource Conservation Service (NRCS). 2002. Wetland determination (WETS) table for Clark County, Washington

  12. Probabilistic cumulative risk assessment of anti-androgenic pesticides in food.

    NARCIS (Netherlands)

    Müller, A.K.; Bosgra, S.; Boon, P.E.; van der Voet, H.; Nielsen, E.; Ladefoged, O.


    In this paper, we present a cumulative risk assessment of three anti-androgenic pesticides (vinclozolin, procymidone and prochloraz) using the relative potency factor (RPF) approach and an integrated probabilistic risk assessment (IPRA) model. RPFs for each substance were estimated for three

  13. Role of sulfite additives in wine induced asthma: single dose and cumulative dose studies


    Vally, H; Thompson, P


    BACKGROUND—Wine appears to be a significant trigger for asthma. Although sulfite additives have been implicated as a major cause of wine induced asthma, direct evidence is limited. Two studies were undertaken to assess sulfite reactivity in wine sensitive asthmatics. The first study assessed sensitivity to sulfites in wine using a single dose sulfited wine challenge protocol followed by a double blind, placebo controlled challenge. In the second study a cumulative dose su...

  14. High cumulants of conserved charges and their statistical uncertainties (United States)

    Li-Zhu, Chen; Ye-Yin, Zhao; Xue, Pan; Zhi-Ming, Li; Yuan-Fang, Wu


    We study the influence of measured high cumulants of conserved charges on their associated statistical uncertainties in relativistic heavy-ion collisions. With a given number of events, the measured cumulants randomly fluctuate with an approximately normal distribution, while the estimated statistical uncertainties are found to be correlated with corresponding values of the obtained cumulants. Generally, with a given number of events, the larger the cumulants we measure, the larger the statistical uncertainties that are estimated. The error-weighted averaged cumulants are dependent on statistics. Despite this effect, however, it is found that the three sigma rule of thumb is still applicable when the statistics are above one million. Supported by NSFC (11405088, 11521064, 11647093), Major State Basic Research Development Program of China (2014CB845402) and Ministry of Science and Technology (MoST) (2016YFE0104800)

  15. A stochastic multicriteria model for evidence-based decision making in drug benefit-risk analysis. (United States)

    Tervonen, Tommi; van Valkenhoef, Gert; Buskens, Erik; Hillege, Hans L; Postmus, Douwe


    Drug benefit-risk (BR) analysis is based on firm clinical evidence regarding various safety and efficacy outcomes. In this paper, we propose a new and more formal approach for constructing a supporting multi-criteria model that fully takes into account the evidence on efficacy and adverse drug reactions. Our approach is based on the stochastic multi-criteria acceptability analysis methodology, which allows us to compute the typical value judgments that support a decision, to quantify decision uncertainty, and to compute a comprehensive BR profile. We construct a multi-criteria model for the therapeutic group of second-generation antidepressants. We assess fluoxetine and venlafaxine together with placebo according to incidence of treatment response and three common adverse drug reactions by using data from a published study. Our model shows that there are clear trade-offs among the treatment alternatives. Copyright © 2011 John Wiley & Sons, Ltd.

  16. How to Find Exculpatory and Inculpatory Evidence Using a Circular Digital Forensics Process Model (United States)

    Khatir, Marjan; Hejazi, Seyed Mahmood

    With raising the number of cyber crimes, the need of having a proper digital forensic process also increases. Although digital forensics is practiced in recent years, there is still a big gap between previously suggested digital forensics processes and what is really needed to be done in real cases. Some problems with current processes are lack of flexible transition between phases, not having a clear method or a complete scenario for addressing reliable evidence, and not paying enough attention to management aspects and team roles. This paper provides a process model by paying special attention to the team roles and management aspects as well as both exculpatory and inculpatory evidence.

  17. Improving Rolling Bearing Fault Diagnosis by DS Evidence Theory Based Fusion Model

    Directory of Open Access Journals (Sweden)

    Xuemei Yao


    Full Text Available Rolling bearing plays an important role in rotating machinery and its working condition directly affects the equipment efficiency. While dozens of methods have been proposed for real-time bearing fault diagnosis and monitoring, the fault classification accuracy of existing algorithms is still not satisfactory. This work presents a novel algorithm fusion model based on principal component analysis and Dempster-Shafer evidence theory for rolling bearing fault diagnosis. It combines the advantages of the learning vector quantization (LVQ neural network model and the decision tree model. Experiments under three different spinning bearing speeds and two different crack sizes show that our fusion model has better performance and higher accuracy than either of the base classification models for rolling bearing fault diagnosis, which is achieved via synergic prediction from both types of models.

  18. Bayesian model selection without evidences: application to the dark energy equation-of-state (United States)

    Hee, S.; Handley, W. J.; Hobson, M. P.; Lasenby, A. N.


    A method is presented for Bayesian model selection without explicitly computing evidences, by using a combined likelihood and introducing an integer model selection parameter n so that Bayes factors, or more generally posterior odds ratios, may be read off directly from the posterior of n. If the total number of models under consideration is specified a priori, the full joint parameter space (θ, n) of the models is of fixed dimensionality and can be explored using standard Markov chain Monte Carlo (MCMC) or nested sampling methods, without the need for reversible jump MCMC techniques. The posterior on n is then obtained by straightforward marginalization. We demonstrate the efficacy of our approach by application to several toy models. We then apply it to constraining the dark energy equation of state using a free-form reconstruction technique. We show that Λ cold dark matter is significantly favoured over all extensions, including the simple w(z) = constant model.

  19. Micropublications: a semantic model for claims, evidence, arguments and annotations in biomedical communications. (United States)

    Clark, Tim; Ciccarese, Paolo N; Goble, Carole A


    Scientific publications are documentary representations of defeasible arguments, supported by data and repeatable methods. They are the essential mediating artifacts in the ecosystem of scientific communications. The institutional "goal" of science is publishing results. The linear document publication format, dating from 1665, has survived transition to the Web. Intractable publication volumes; the difficulty of verifying evidence; and observed problems in evidence and citation chains suggest a need for a web-friendly and machine-tractable model of scientific publications. This model should support: digital summarization, evidence examination, challenge, verification and remix, and incremental adoption. Such a model must be capable of expressing a broad spectrum of representational complexity, ranging from minimal to maximal forms. The micropublications semantic model of scientific argument and evidence provides these features. Micropublications support natural language statements; data; methods and materials specifications; discussion and commentary; challenge and disagreement; as well as allowing many kinds of statement formalization. The minimal form of a micropublication is a statement with its attribution. The maximal form is a statement with its complete supporting argument, consisting of all relevant evidence, interpretations, discussion and challenges brought forward in support of or opposition to it. Micropublications may be formalized and serialized in multiple ways, including in RDF. They may be added to publications as stand-off metadata. An OWL 2 vocabulary for micropublications is available at A discussion of this vocabulary along with RDF examples from the case studies, appears as OWL Vocabulary and RDF Examples in Additional file 1. Micropublications, because they model evidence and allow qualified, nuanced assertions, can play essential roles in the scientific communications ecosystem in places where simpler, formalized and

  20. An Empirical Investigation of the Black-Scholes Model: Evidence from the Australian Stock Exchange

    Directory of Open Access Journals (Sweden)

    Zaffar Subedar


    Full Text Available This paper evaluates the probability of an exchange traded European call option beingexercised on the ASX200 Options Index. Using single-parameter estimates of factors withinthe Black-Scholes model, this paper utilises qualitative regression and a maximum likelihoodapproach. Results indicate that the Black-Scholes model is statistically significant at the 1%level. The results also provide evidence that the use of implied volatility and a jump-diffusionapproach, which increases the tail properties of the underlying lognormal distribution,improves the statistical significance of the Black-Scholes model.

  1. Reconstructing an f(R) model from holographic dark energy: using the observational evidence

    International Nuclear Information System (INIS)

    Saaidi, Kh; Aghamohammadi, A


    We investigate the correspondence relation between f(R) gravity and an interacting holographic dark energy (HDE). By obtaining the conditions needed for some observational evidence such as positive acceleration expansion of the Universe, crossing the phantom divide line and validity of the thermodynamics second law in an interacting HDE model and corresponding it with the f(R) model of gravity, we find a viable f(R) model that can explain the present Universe. We also obtain the explicit evolutionary forms of the corresponding scalar field, potential and scale factor of the Universe. (paper)

  2. Cumulative Risk and Physiological Stress Responses in African American Adolescents. (United States)

    Kliewer, Wendy; Robins, Jo Lynne W


    To investigate associations between components of cumulative risk (CR) and physiological stress responses in African American adolescents and evaluate emotion regulation as a mediator and sex as a moderator of these associations. Cortisol and salivary alpha amylase (sAA) were collected in adolescents ( N = 205; 55% female; 12.1 ± 1.6 years at baseline) as part of a longitudinal study of stress and adjustment in families. CR was assessed at baseline and emotion regulation was assessed at baseline and 2 years later at Wave 3 (W3) using caregiver and adolescent reports. Cortisol and sAA responses to the social competence interview were assessed at W3. Repeated-measures analyses of variance predicting cortisol and controlling for time of day, adolescent age, medication usage, and pubertal status revealed significant interactions of time with both psychosocial and sociodemographic risk. In both analyses, youths with higher levels of risk showed a steeper decline in cortisol than youths with lower levels of risk. In parallel analyses predicting sAA, time interacted with psychosocial but not with sociodemographic risk. There were no interactions with sex in any of the analyses. Although CR was associated with changes in emotion regulation, there was no evidence that these changes accounted for the observed CR-stress response associations. These findings illustrate the potential importance of disentangling CR and suggest that additional work is needed to help explicate why and how CR is associated with specific physiological responses to stress.

  3. Longhi Games, Internal Reservoirs, and Cumulate Porosity (United States)

    Morse, S. A.


    Fe in plagioclase at an early age, T-rollers (or not) on the Di-Trid boundary in Fo-Di-Sil, the mantle solidus, origins of anorthosites, esoteric uses of Schreinemakers rules and many more topics are all fresh and pleasant memories of John Longhi's prolific and creative work. The Fram-Longhi experimental effect of pressure on plagioclase partitioning with liquid in mafic rocks became essential to an understanding of multiphase Rayleigh fractionation of plagioclase in big layered intrusions. Only by using the pressure effect could I find a good equation through the data for the Kiglapait intrusion, and that result among others required the existence with probability 1.0 of an internal reservoir (Morse, JPet 2008). Knowledge of cumulate porosity is a crucial key to the understanding of layered igneous rocks. We seek both the initial (inverse packing fraction) and residual porosity to find the time and process path from sedimentation to solidification. In the Kiglapait Lower Zone we have a robust estimate of mean residual porosity from the modes of the excluded phases augite, oxides, sulfide, and apatite. To this we apply the maximum variance of plagioclase composition (the An range) to find an algorithm that extends through the Upper Zone and to other intrusions. Of great importance is that all these measurements were made in grain mounts concentrated from typically about 200 g of core or hand specimen, hence the represented sample volume is thousands of times greater than for a thin section. The resulting distribution and scatter of the An range is novel and remarkable. It is V-shaped in the logarithmic representation of stratigraphic height, running from about 20 mole % at both ends (base to top of the Layered Series) to near-zero at 99 PCS. The intercept of the porosity-An range relation gives An range = 3.5 % at zero residual porosity. Petrographic analysis reveals that for PCS less than 95 and greater than 99.9, the An range is intrinsic, i.e. pre-cumulus, for

  4. Integration of an Evidence Base into a Probabilistic Risk Assessment Model. The Integrated Medical Model Database: An Organized Evidence Base for Assessing In-Flight Crew Health Risk and System Design (United States)

    Saile, Lynn; Lopez, Vilma; Bickham, Grandin; FreiredeCarvalho, Mary; Kerstman, Eric; Byrne, Vicky; Butler, Douglas; Myers, Jerry; Walton, Marlei


    This slide presentation reviews the Integrated Medical Model (IMM) database, which is an organized evidence base for assessing in-flight crew health risk. The database is a relational database accessible to many people. The database quantifies the model inputs by a ranking based on the highest value of the data as Level of Evidence (LOE) and the quality of evidence (QOE) score that provides an assessment of the evidence base for each medical condition. The IMM evidence base has already been able to provide invaluable information for designers, and for other uses.

  5. The cumulative effect of air pollutants on the acute exacerbation of COPD in Shanghai, China. (United States)

    Sun, Xian Wen; Chen, Pei Li; Ren, Lei; Lin, Ying Ni; Zhou, Jian Ping; Ni, Lei; Li, Qing Yun


    Epidemiologic studies have shown the effect of air pollutants on acute exacerbation of chronic obstructive pulmonary disease (AECOPD). However, little is known regarding the dose-response relationship. This study aimed to investigate the cumulative effect of air pollutants on AECOPD. We collected 101 patients with AECOPD from November 2010 through August 2011 in Shanghai. Multiple logistic regression was used to estimate associations between air pollutants and AECOPD. Poisson regression was then applied to determine the cumulative effect of air pollutants including particulate matter 10 (PM10), PM2.5, nitrogen dioxide (NO 2 ), sulphur dioxide (SO 2 ) and ozone (O 3 ) on AECOPD, of which the seasonal variation was further explored. The monthly episodes of AECOPD were associated with the concentrations of PM2.5 (r=0.884, peffect in cold season, whereas 7days in warm season. The RR for AECOPD for per 10μg/m 3 increment in NO 2 was 1.07, with a 5-day cumulative effect without seasonal variation. High consecutive levels of PM2.5 and NO 2 increase the risk of developing AECOPD. Cumulative effect of PM2.5 and NO 2 appears before the exacerbation onset. These gradations were more evident in the PM2.5 during different seasons. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Nonsymbolic number and cumulative area representations contribute shared and unique variance to symbolic math competence. (United States)

    Lourenco, Stella F; Bonny, Justin W; Fernandez, Edmund P; Rao, Sonia


    Humans and nonhuman animals share the capacity to estimate, without counting, the number of objects in a set by relying on an approximate number system (ANS). Only humans, however, learn the concepts and operations of symbolic mathematics. Despite vast differences between these two systems of quantification, neural and behavioral findings suggest functional connections. Another line of research suggests that the ANS is part of a larger, more general system of magnitude representation. Reports of cognitive interactions and common neural coding for number and other magnitudes such as spatial extent led us to ask whether, and how, nonnumerical magnitude interfaces with mathematical competence. On two magnitude comparison tasks, college students estimated (without counting or explicit calculation) which of two arrays was greater in number or cumulative area. They also completed a battery of standardized math tests. Individual differences in both number and cumulative area precision (measured by accuracy on the magnitude comparison tasks) correlated with interindividual variability in math competence, particularly advanced arithmetic and geometry, even after accounting for general aspects of intelligence. Moreover, analyses revealed that whereas number precision contributed unique variance to advanced arithmetic, cumulative area precision contributed unique variance to geometry. Taken together, these results provide evidence for shared and unique contributions of nonsymbolic number and cumulative area representations to formally taught mathematics. More broadly, they suggest that uniquely human branches of mathematics interface with an evolutionarily primitive general magnitude system, which includes partially overlapping representations of numerical and nonnumerical magnitude.

  7. An analysis of cumulative risks based on biomonitoring data for six phthalates using the Maximum Cumulative Ratio (United States)

    The Maximum Cumulative Ratio (MCR) quantifies the degree to which a single chemical drives the cumulative risk of an individual exposed to multiple chemicals. Phthalates are a class of chemicals with ubiquitous exposures in the general population that have the potential to cause ...

  8. Sworn testimony of the model evidence: Gaussian Mixture Importance (GAME) sampling (United States)

    Volpi, Elena; Schoups, Gerrit; Firmani, Giovanni; Vrugt, Jasper A.


    What is the "best" model? The answer to this question lies in part in the eyes of the beholder, nevertheless a good model must blend rigorous theory with redeeming qualities such as parsimony and quality of fit. Model selection is used to make inferences, via weighted averaging, from a set of K candidate models, Mk; k=>(1,…,K>), and help identify which model is most supported by the observed data, Y>˜=>(y˜1,…,y˜n>). Here, we introduce a new and robust estimator of the model evidence, p>(Y>˜|Mk>), which acts as normalizing constant in the denominator of Bayes' theorem and provides a single quantitative measure of relative support for each hypothesis that integrates model accuracy, uncertainty, and complexity. However, p>(Y>˜|Mk>) is analytically intractable for most practical modeling problems. Our method, coined GAussian Mixture importancE (GAME) sampling, uses bridge sampling of a mixture distribution fitted to samples of the posterior model parameter distribution derived from MCMC simulation. We benchmark the accuracy and reliability of GAME sampling by application to a diverse set of multivariate target distributions (up to 100 dimensions) with known values of p>(Y>˜|Mk>) and to hypothesis testing using numerical modeling of the rainfall-runoff transformation of the Leaf River watershed in Mississippi, USA. These case studies demonstrate that GAME sampling provides robust and unbiased estimates of the evidence at a relatively small computational cost outperforming commonly used estimators. The GAME sampler is implemented in the MATLAB package of DREAM and simplifies considerably scientific inquiry through hypothesis testing and model selection.

  9. Sentence-based attention mechanisms in word learning: Evidence from a computational model

    Directory of Open Access Journals (Sweden)

    Afra eAlishahi


    Full Text Available When looking for the referents of nouns, adults and young children are sensitive to cross- situational statistics (Yu & Smith, 2007; Smith & Yu, 2008. In addition, the linguistic context that a word appears in has been shown to act as a powerful attention mechanism for guiding sentence processing and word learning (Landau & Gleitman, 1985; Altmann & Kamide, 1999; Kako & Trueswell, 2000. Koehne & Crocker (2010, 2011 investigate the interaction between cross-situational evidence and guidance from the sentential context in an adult language learning scenario. Their studies reveal that these learning mechanisms interact in a complex manner: they can be used in a complementary way when context helps reduce referential uncertainty; they influence word learning about equally strongly when cross-situational and contextual evidence are in conflict; and contextual cues block aspects of cross-situational learning when both mechanisms are independently applicable. To address this complex pattern of findings, we present a probabilistic computational model of word learning which extends a previous cross-situational model (Fazly et al., 2010 with an attention mechanism based on sentential cues. Our model uses a framework that seamlessly combines the two sources of evidence in order to study their emerging pattern of interaction during the process of word learning. Simulations of the experiments of Koehne & Crocker (2010, 2011 reveal an overall patterns of results that are in line with their findings. Importantly, we demonstrate that our model does not need to explicitly assign priority to either source of evidence in order to produce these results: learning patterns emerge as a result of a probabilistic interaction between the two types of cues. Moreover, using a computational model allows us to examine the developmental trajectory of the differential roles of cross-situational and sentential cues in word learning.

  10. Making Steppingstones out of Stumbling Blocks: A New Bayesian Model Evidence Estimator with Application to Groundwater Model Selection (United States)

    Ye, M.; Elshall, A. S.; Tang, G.; Samani, S.


    Bayesian Model Evidence (BME) is the measure of the average fit of the model to data given all the parameter values that the model can take. By accounting for the trade-off between the model ability to reproduce the observation data and model complexity, BME estimates of candidate models are employed to calculate model weights, which are used for model selection and model averaging. This study shows that accurate estimation of the BME is important for penalizing models with more complexity. To improve the accuracy of BME estimation, we resort to Monte Carlo numerical estimators over semi-analytical solutions (such as Laplace approximations, BIC, KIC and other). This study examines prominent numerical estimators of BME that are the thermodynamic integration (TI), and the importance sampling methods of arithmetic mean (AM), harmonic mean (HM), and steppingstone sampling (SS). AM estimator (based on prior sampling) and HM estimator (based on posterior sampling) are straightforward to implement, yet they lead to under and over estimation, respectively. TI and SS improve beyond this by means of sampling multiple intermediate distributions that links the prior and the posterior, using Markov Chain Monte Carlo (MCMC). TI and SS are theoretically unbiased estimators that are mathematically rigorous. Yet a theoretically unbiased estimator could have large bias in practice arising from numerical implementation, because MCMC sampling errors of certain intermediate distributions can introduce bias. We propose an SS variant, namely the multiple one-steppingstone sampling (MOSS), which turns these intermediate stumbling "blocks" of SS into steppingstones toward BME estimation. Thus, MOSS is less sensitive to MCMC sampling errors. We evaluate these estimators using a problem of groundwater transport model selection. The modeling results show that SS and MOSS estimators gave the most accurate results. In addition, the results show that the magnitude of the estimation error is a

  11. Converging evidence of mitochondrial dysfunction in a yeast model of homocysteine metabolism imbalance. (United States)

    Kumar, Arun; John, Lijo; Maity, Shuvadeep; Manchanda, Mini; Sharma, Abhay; Saini, Neeru; Chakraborty, Kausik; Sengupta, Shantanu


    An elevated level of homocysteine, a thiol amino acid, is associated with various complex disorders. The cellular effects of homocysteine and its precursors S-adenosylhomocysteine (AdoHcy) and S-adenosylmethionine (AdoMet) are, however, poorly understood. We used Saccharomyces cerevisiae as a model to understand the basis of pathogenicity induced by homocysteine and its precursors. Both homocysteine and AdoHcy but not AdoMet inhibited the growth of the str4Δ strain (which lacks the enzyme that converts homocysteine to cystathionine-mimicking vascular cells). Addition of AdoMet abrogated the inhibitory effect of AdoHcy but not that of homocysteine indicating that an increase in the AdoMet/AdoHcy ratio is sufficient to overcome the AdoHcy-mediated growth defect but not that of homocysteine. Also, the transcriptomic profile of AdoHcy and homocysteine showed gross dissimilarity based on gene enrichment analysis. Furthermore, compared with homocysteine, AdoHcy treatment caused a higher level of oxidative stress in the cells. However, unlike a previously reported response in wild type (Kumar, A., John, L., Alam, M. M., Gupta, A., Sharma, G., Pillai, B., and Sengupta, S. (2006) Biochem. J. 396, 61-69), the str4Δ strain did not exhibit an endoplasmic reticulum stress response. This suggests that homocysteine induces varied response depending on the flux of homocysteine metabolism. We also observed altered expression of mitochondrial genes, defective membrane potential, and fragmentation of the mitochondrial network together with the increased expression of fission genes indicating that the imbalance in homocysteine metabolism has a major effect on mitochondrial functions. Furthermore, treatment of cells with homocysteine or AdoHcy resulted in apoptosis as revealed by annexin V staining and TUNEL assay. Cumulatively, our results suggest that elevated levels of homocysteine lead to mitochondrial dysfunction, which could potentially initiate pro-apoptotic pathways, and this

  12. Converging Evidence of Mitochondrial Dysfunction in a Yeast Model of Homocysteine Metabolism Imbalance* (United States)

    Kumar, Arun; John, Lijo; Maity, Shuvadeep; Manchanda, Mini; Sharma, Abhay; Saini, Neeru; Chakraborty, Kausik; Sengupta, Shantanu


    An elevated level of homocysteine, a thiol amino acid, is associated with various complex disorders. The cellular effects of homocysteine and its precursors S-adenosylhomocysteine (AdoHcy) and S-adenosylmethionine (AdoMet) are, however, poorly understood. We used Saccharomyces cerevisiae as a model to understand the basis of pathogenicity induced by homocysteine and its precursors. Both homocysteine and AdoHcy but not AdoMet inhibited the growth of the str4Δ strain (which lacks the enzyme that converts homocysteine to cystathionine-mimicking vascular cells). Addition of AdoMet abrogated the inhibitory effect of AdoHcy but not that of homocysteine indicating that an increase in the AdoMet/AdoHcy ratio is sufficient to overcome the AdoHcy-mediated growth defect but not that of homocysteine. Also, the transcriptomic profile of AdoHcy and homocysteine showed gross dissimilarity based on gene enrichment analysis. Furthermore, compared with homocysteine, AdoHcy treatment caused a higher level of oxidative stress in the cells. However, unlike a previously reported response in wild type (Kumar, A., John, L., Alam, M. M., Gupta, A., Sharma, G., Pillai, B., and Sengupta, S. (2006) Biochem. J. 396, 61–69), the str4Δ strain did not exhibit an endoplasmic reticulum stress response. This suggests that homocysteine induces varied response depending on the flux of homocysteine metabolism. We also observed altered expression of mitochondrial genes, defective membrane potential, and fragmentation of the mitochondrial network together with the increased expression of fission genes indicating that the imbalance in homocysteine metabolism has a major effect on mitochondrial functions. Furthermore, treatment of cells with homocysteine or AdoHcy resulted in apoptosis as revealed by annexin V staining and TUNEL assay. Cumulatively, our results suggest that elevated levels of homocysteine lead to mitochondrial dysfunction, which could potentially initiate pro-apoptotic pathways, and

  13. Moving Low-Carbon Construction Industry in Jiangsu Province: Evidence from Decomposition and Decoupling Models

    Directory of Open Access Journals (Sweden)

    Rongrong Li


    Full Text Available The carbon dioxide (CO2 emissions caused by the global construction industry account for 36% of the world’s total carbon emissions, and 50% of China’s total carbon emissions. The carbon emissions from Jiangsu Province’s construction industry account for approximately 16% of the total emissions of the Chinese construction industry. Taking the construction industry in Jiangsu Province as our study object, therefore, this paper introduces the Intergovernmental Panel on Climate Change (IPCC carbon emission accounting method as a means to measure the total CO2 emissions of the Jiangsu Province construction industry. Specifically, we examine the period from 2005 to 2013. Based on the Tapio decoupling model, we analyze the decoupling state between the CO2 emissions of the construction industry in Jiangsu Province and the province’s economic growth. Our paper also employs the Logarithmic Mean Divisia Index (LMDI approach, in order to conduct a decomposition analysis of those factors that influenced the changes in the level of CO2 emissions during the studied period. According to the results of our research, during the period from 2005 to 2013, the CO2 emission levels caused by the construction industry in Jiangsu Province experienced a significant increase. The cumulative total CO2 emissions reached 402.85 million tons. During most of the years covered by our study, an expansive negative decoupling state existed between the level of CO2 emissions and the output value of Jiangsu’s construction industry. These periods were interspersed with either a weak decoupling state in some years or a strong decoupling state in other years. The indirect carbon emission intensity effect and the industry scale effect were the main factors influencing the increases in the construction industry’s CO2 emissions. At the conclusion of our paper, we put forward policy suggestions, with the objective of promoting the de-carbonization of the construction industry

  14. Bridging science and traditional knowledge to assess cumulative impacts of stressors on ecosystem health. (United States)

    Mantyka-Pringle, Chrystal S; Jardine, Timothy D; Bradford, Lori; Bharadwaj, Lalita; Kythreotis, Andrew P; Fresque-Baxter, Jennifer; Kelly, Erin; Somers, Gila; Doig, Lorne E; Jones, Paul D; Lindenschmidt, Karl-Erich


    Cumulative environmental impacts driven by anthropogenic stressors lead to disproportionate effects on indigenous communities that are reliant on land and water resources. Understanding and counteracting these effects requires knowledge from multiple sources. Yet the combined use of Traditional Knowledge (TK) and Scientific Knowledge (SK) has both technical and philosophical hurdles to overcome, and suffers from inherently imbalanced power dynamics that can disfavour the very communities it intends to benefit. In this article, we present a 'two-eyed seeing' approach for co-producing and blending knowledge about ecosystem health by using an adapted Bayesian Belief Network for the Slave River and Delta region in Canada's Northwest Territories. We highlight how bridging TK and SK with a combination of field data, interview transcripts, existing models, and expert judgement can address key questions about ecosystem health when considerable uncertainty exists. SK indicators (e.g., bird counts, mercury in fish, water depth) were graded as moderate, whereas TK indicators (e.g., bird usage, fish aesthetics, changes to water flow) were graded as being poor in comparison to the past. SK indicators were predominantly spatial (i.e., comparing to other locations) while the TK indicators were predominantly temporal (i.e., comparing across time). After being populated by 16 experts (local harvesters, Elders, governmental representatives, and scientists) using both TK and SK, the model output reported low probabilities that the social-ecological system is healthy as it used to be. We argue that it is novel and important to bridge TK and SK to address the challenges of environmental change such as the cumulative impacts of multiple stressors on ecosystems and the services they provide. This study presents a critical social-ecological tool for widening the evidence-base to a more holistic understanding of the system dynamics of multiple environmental stressors in ecosystems and for

  15. Forensic Evidence Identification and Modeling for Attacks against a Simulated Online Business Information System

    Directory of Open Access Journals (Sweden)

    Manghui Tu


    Full Text Available Forensic readiness can support future forensics investigation or auditing on external/internal attacks, internal sabotage and espionage, and business frauds. To establish forensics readiness, it is essential for an organization to identify what evidences are relevant and where they can be found, to determine whether they are logged in a forensic sound way and whether all the needed evidences are available to reconstruct the events successfully.  Our goal of this research is to ensure evidence availability. First, both external and internal attacks are molded as augmented attack trees/graphs based on the system vulnerabilities. Second, modeled attacks are conducted against a honeynet simulating an online business information system, and each honeypot's hard drive is forensic sound imaged for each individual attack. Third, an evidence tree/graph will be built after forensics examination on the disk images for each attack. The evidence trees/graphs are expected to be used for automatic crime scene reconstruction and automatic attack/fraud detection in the future.

  16. A Community-Based Participatory Research Guided Model for the Dissemination of Evidence-Based Interventions. (United States)

    Delafield, Rebecca; Hermosura, Andrea Nacapoy; Ing, Claire Townsend; Hughes, Claire K; Palakiko, Donna-Marie; Dillard, Adrienne; Kekauoha, B Puni; Yoshimura, Sheryl R; Gamiao, Shari; Kaholokula, Joseph Keawe

    Dissemination is a principle within community-based participatory research (CBPR); however, published research focuses on the dissemination of findings from CBPR projects but less on dissemination of interventions developed through CBPR approaches. To disseminate an evidence-based lifestyle intervention tailored for Native Hawaiians and other Pacific Islanders, the PILI 'Ohana Project (POP), an 11-year CBPR initiative, developed an innovative dissemination model. The community-to-community mentoring (CCM) model described in this paper extends the application of CBPR values and principles used in intervention development to intervention dissemination. The CCM model combines a CBPR orientation with the diffusion of innovation theory, the social cognitive theory, and key concepts from community organizing and community building to address the multilevel factors that influence uptake of an evidence-based intervention (EBI). Grounding the model in CBPR principles provides benefits for intervention dissemination and integrates a focus on community benefits and capacity building. By establishing co-equal, mutually beneficial relationships at the core of the CCM model, opportunities are created for building critical consciousness, community capacity, and social capital. More research is needed to determine the effectiveness of this model of intervention dissemination which may enhance diffusion of CBPR interventions and empower communities in the process.

  17. Simulation of the cumulative hydrological response to green infrastructure (United States)

    Avellaneda, P. M.; Jefferson, A. J.; Grieser, J. M.; Bush, S. A.


    In this study, we evaluated the cumulative hydrologic performance of green infrastructure in a residential area of the city of Parma, Ohio, draining to a tributary of the Cuyahoga River. Green infrastructure included the following spatially distributed devices: 16 street-side bioretention cells, 7 rain gardens, and 37 rain barrels. Data consisted of rainfall and outfall flow records for a wide range of storm events, including pretreatment and treatment periods. The Stormwater Management Model was calibrated and validated to predict the hydrologic response of green infrastructure. The calibrated model was used to quantify annual water budget alterations and discharge frequency over a 6 year simulation period. For the study catchment, we observed a treatment effect with increases of 1.4% in evaporation, 7.6% in infiltration, and a 9.0% reduction in surface runoff. The hydrologic performance of green infrastructure was evaluated by comparing the flow duration curve for pretreatment and treatment outfall flow scenarios. The flow duration curve shifted downward for the green infrastructure scenario. Discharges with a 0.5, 1, 2, and 5 year return period were reduced by an average of 29%. Parameter and predictive uncertainties were inspected by implementing a Bayesian statistical approach.

  18. Breaking Bad News: An Evidence-Based Review of Communication Models for Oncology Nurses. (United States)

    Bumb, Meridith; Keefe, Joanna; Miller, Lindsay; Overcash, Janine


    A diagnosis of cancer is a stressful, difficult, and life-altering event. Breaking bad news is distressing to patients and families and is often uncomfortable for the nurse delivering it. Evidence-based communication models have been developed and adapted for use in clinical practice to assist nurses with breaking bad news.

. The purpose of this article is to provide an overview on breaking bad news and to review the utility of the SPIKES and PEWTER evidence-based communication models for oncology nurses.
. Perceptions of breaking bad news from the nurse and patient perspectives, as well as barriers and consequences to effective communication, will be presented. Clinical examples of possible situations of breaking bad news will demonstrate how to use the SPIKES and PEWTER models of communication when disclosing bad news to patients and their families.
. By using the evidence-based communication strategies depicted in this article, oncology nurses can support the delivery of bad news and maintain communication with their patients and their patients' families in an effective and productive manner.

  19. Cumulative trauma and partner conflict predict post-traumatic stress disorder in postpartum African-American women. (United States)

    Hauff, Nancy J; Fry-McComish, Judith; Chiodo, Lisa M


    To describe relationships between cumulative trauma, partner conflict and post-traumatic stress in African-American postpartum women. Cumulative trauma exposure estimates for women in the USA range from 51-69%. During pregnancy, most trauma research has focused on physical injury to the mother. Post-traumatic stress disorder (PTSD) is associated with trauma and more prevalent in African-American women than women of other groups. Knowledge about both the rate and impact of cumulative trauma on pregnancy may contribute to our understanding of women seeking prenatal care, and disparities in infant morbidity and mortality. This retrospective, correlational, cross-sectional study took place on postpartum units of two Detroit hospitals. Participants were 150 African-American women aged between 18-45 who had given birth. Mothers completed the Cumulative Trauma Scale, Conflict Tactics Scale, Clinician Administered Post-traumatic Stress Scale, Edinburgh Postnatal Depression Scale and a Demographic Data form. Descriptive statistics, correlations and multiple regressions were used for data analysis. All participants reported at least one traumatic event in their lifetime. Cumulative trauma and partner conflict predicted PTSD, with the trauma of a life-threatening event for a loved one reported by 60% of the sample. Nearly, one-fourth of the women screened were at risk for PTSD. Increased cumulative trauma, increased partner conflict and lower level of education were related to higher rates of PTSD symptoms. Both cumulative trauma and partner conflict in the past year predict PTSD. Reasoning was used most often for partner conflict resolution. The results of this study offer additional knowledge regarding relationships between cumulative trauma, partner conflict and PTSD in African-American women. Healthcare providers need to be sensitive to patient life-threatening events, personal failures, abuse and other types of trauma. Current evidence supports the need to assess for

  20. Estimating population ecology models for the WWW market: evidence of competitive oligopolies. (United States)

    de Cabo, Ruth Mateos; Gimeno, Ricardo


    This paper proposes adapting a particle filtering algorithm to model online Spanish real estate and job search market segments based on the Lotka-Volterra competition equations. For this purpose the authors use data on Internet information searches from Google Trends to proxy for market share. Market share evolution estimations are coherent with those observed in Google Trends. The results show evidence of low website incompatibility in the markets analyzed. Competitive oligopolies are most common in such low-competition markets, instead of the monopolies predicted by theoretical ecology models under strong competition conditions.

  1. Cumulative Impact Assessment: Approaching Environmental Capacity in Development Area Using Environmental Impact Assessment Information (United States)

    Cho, N.; Lee, M. J.; Maeng, J. H.


    Environmental impact assessment estimates the impact of development as a business unit and establishes mitigation plan. If the development is done, its economic effects can spread to the nearby areas. So that various developments can be distributed at different time intervals. The impact of the new developments can be combined with existing environmental impacts and can have a larger impact. That is, Cumulative impact assessment is needed to consider the environmental capacity of the Nearby area. Cumulative impact assessments require policy tools such as environmental impact assessment information and cumulative impact estimation models. In Korea, environmental information (water quality, air quality, etc.) of the development site is measured for environmental impact assessment and monitored for a certain period (generally 5 years) after the project. In addition, by constructing the environmental information as a spatial database, it is possible to express the environmental impact on a regional basis spatially and to intuitively use it for development site selection. Utilizing a composite model of environmental impact assessment information and Remote Sensing data for cumulative impact estimation, That can be used as a policy decision support tool that provides quantitative information for development area management, such as time series effect and sprawl phenomenon.

  2. Evidence for Symplectic Symmetry in Ab Initio No-Core Shell Model Results for Light Nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Dytrych, Tomas; Sviratcheva, Kristina D.; Bahri, Chairul; Draayer, Jerry P.; /Louisiana State U.; Vary, James P.; /Iowa State U. /LLNL, Livermore /SLAC


    Clear evidence for symplectic symmetry in low-lying states of {sup 12}C and {sup 16}O is reported. Eigenstates of {sup 12}C and {sup 16}O, determined within the framework of the no-core shell model using the JISP16 NN realistic interaction, typically project at the 85-90% level onto a few of the most deformed symplectic basis states that span only a small fraction of the full model space. The results are nearly independent of whether the bare or renormalized effective interactions are used in the analysis. The outcome confirms Elliott's SU(3) model which underpins the symplectic scheme, and above all, points to the relevance of a symplectic no-core shell model that can reproduce experimental B(E2) values without effective charges as well as deformed spatial modes associated with clustering phenomena in nuclei.

  3. Brief Strategic Family Therapy: Implementing evidence-based models in community settings (United States)

    Szapocznik, José; Muir, Joan A.; Duff, Johnathan H.; Schwartz, Seth J.; Brown, C. Hendricks


    Reflecting a nearly 40-year collaborative partnership between clinical researchers and clinicians, the present article reviews the authors’ experience in developing, investigating, and implementing the Brief Strategic Family Therapy (BSFT) model. The first section of the article focuses on the theory, practice, and studies related to this evidence-based family therapy intervention targeting adolescent drug abuse and delinquency. The second section focuses on the implementation model created for the BSFT intervention– a model that parallels many of the recommendations furthered within the implementation science literature. Specific challenges encountered during the BSFT implementation process are reviewed, along with ways of conceptualizing and addressing these challenges from a systemic perspective. The implementation approach that we employ uses the same systemic principles and intervention techniques as those that underlie the BSFT model itself. Recommendations for advancing the field of implementation science, based on our on-the-ground experiences, are proposed. PMID:24274187

  4. Indirect Effects and Potential Cumulative Impacts of Dredging in an Urbanized Estuary (United States)

    Sommerfield, C. K.; Chen, J.; Ralston, D. K.; Geyer, W. R.


    For over two centuries, the Delaware River and Bay estuary has supported one of the most economically important ports in the United States. To accommodate ships of ever-increasing size, the 165-km axial shipping channel has been deepened to over twice the natural depth of the estuary. While it is known that the channel has modified tides and sedimentation patterns in the estuary, unknown are the impacts on the ecosystem as a whole. A concern is the influence of channelization on sediment movement to the tidal wetland coast, which is eroding at rates on the order of meters per year. Tidal wetlands frame the entire estuary and provide vital ecosystem services ranging from recreation to carbon sequestration. To identify shifts in baseline conditions, we are performing a retrospective analysis of estuarine dynamics using historical bathymetry, numerical modeling, and observational studies. The period of interest extends from 1848 (50 years prior to channel construction) to present. During this period the channel was progressively deepened from its natural depth of 5.5 m to the current depth of 14 m. Preliminary modeling results support independent evidence that the salt intrusion and zone of rapid sediment deposition migrated several 10s of kilometers up-estuary as an indirect effect of deepening. Ironically, the locus of intense deposition now falls squarely within the Wilmington-Philadelphia port complex; river sediment that initially settles in this area is removed by maintenance dredging before it can disperse seaward. Sediment budgetary analysis indicates that the mass of sediment dredged from the upper estuary on average exceeds the mass of the new sediment supplied from the drainage basin. Hence, a probable cumulative impact of dredging is a reduction in sediment delivery to the lower estuary and fringing wetlands. Connections among the shipping channel, wave-tide interactions, and marsh edge erosion are a topic of ongoing modeling and observational research.

  5. Using Time-Varying Evidence to Test Models of Decision Dynamics: Bounded Diffusion vs. the Leaky Competing Accumulator Model. (United States)

    Tsetsos, Konstantinos; Gao, Juan; McClelland, James L; Usher, Marius


    When people make decisions, do they give equal weight to evidence arriving at different times? A recent study (Kiani et al., 2008) using brief motion pulses (superimposed on a random moving dot display) reported a primacy effect: pulses presented early in a motion observation period had a stronger impact than pulses presented later. This observation was interpreted as supporting the bounded diffusion (BD) model and ruling out models in which evidence accumulation is subject to leakage or decay of early-arriving information. We use motion pulses and other manipulations of the timing of the perceptual evidence in new experiments and simulations that support the leaky competing accumulator (LCA) model as an alternative to the BD model. While the LCA does include leakage, we show that it can exhibit primacy as a result of competition between alternatives (implemented via mutual inhibition), when the inhibition is strong relative to the leak. Our experiments replicate the primacy effect when participants must be prepared to respond quickly at the end of a motion observation period. With less time pressure, however, the primacy effect is much weaker. For 2 (out of 10) participants, a primacy bias observed in trials where the motion observation period is short becomes weaker or reverses (becoming a recency effect) as the observation period lengthens. Our simulation studies show that primacy is equally consistent with the LCA or with BD. The transition from primacy-to-recency can also be captured by the LCA but not by BD. Individual differences and relations between the LCA and other models are discussed.

  6. Interagency Collaborative Team Model for Capacity Building to Scale-Up Evidence-Based Practice. (United States)

    Hurlburt, Michael; Aarons, Gregory A; Fettes, Danielle; Willging, Cathleen; Gunderson, Lara; Chaffin, Mark J


    System-wide scale up of evidence-based practice (EBP) is a complex process. Yet, few strategic approaches exist to support EBP implementation and sustainment across a service system. Building on the Exploration, Preparation, Implementation, and Sustainment (EPIS) implementation framework, we developed and are testing the Interagency Collaborative Team (ICT) process model to implement an evidence-based child neglect intervention (i.e., SafeCare®) within a large children's service system. The ICT model emphasizes the role of local agency collaborations in creating structural supports for successful implementation. We describe the ICT model and present preliminary qualitative results from use of the implementation model in one large scale EBP implementation. Qualitative interviews were conducted to assess challenges in building system, organization, and home visitor collaboration and capacity to implement the EBP. Data collection and analysis centered on EBP implementation issues, as well as the experiences of home visitors under the ICT model. Six notable issues relating to implementation process emerged from participant interviews, including: (a) initial commitment and collaboration among stakeholders, (b) leadership, (c) communication, (d) practice fit with local context, (e) ongoing negotiation and problem solving, and (f) early successes. These issues highlight strengths and areas for development in the ICT model. Use of the ICT model led to sustained and widespread use of SafeCare in one large county. Although some aspects of the implementation model may benefit from enhancement, qualitative findings suggest that the ICT process generates strong structural supports for implementation and creates conditions in which tensions between EBP structure and local contextual variations can be resolved in ways that support the expansion and maintenance of an EBP while preserving potential for public health benefit.

  7. Modeling a historical mountain pine beetle outbreak using Landsat MSS and multiple lines of evidence (United States)

    Assal, Timothy J.; Sibold, Jason; Reich, Robin M.


    Mountain pine beetles are significant forest disturbance agents, capable of inducing widespread mortality in coniferous forests in western North America. Various remote sensing approaches have assessed the impacts of beetle outbreaks over the last two decades. However, few studies have addressed the impacts of historical mountain pine beetle outbreaks, including the 1970s event that impacted Glacier National Park. The lack of spatially explicit data on this disturbance represents both a major data gap and a critical research challenge in that wildfire has removed some of the evidence from the landscape. We utilized multiple lines of evidence to model forest canopy mortality as a proxy for outbreak severity. We incorporate historical aerial and landscape photos, aerial detection survey data, a nine-year collection of satellite imagery and abiotic data. This study presents a remote sensing based framework to (1) relate measurements of canopy mortality from fine-scale aerial photography to coarse-scale multispectral imagery and (2) classify the severity of mountain pine beetle affected areas using a temporal sequence of Landsat data and other landscape variables. We sampled canopy mortality in 261 plots from aerial photos and found that insect effects on mortality were evident in changes to the Normalized Difference Vegetation Index (NDVI) over time. We tested multiple spectral indices and found that a combination of NDVI and the green band resulted in the strongest model. We report a two-step process where we utilize a generalized least squares model to account for the large-scale variability in the data and a binary regression tree to describe the small-scale variability. The final model had a root mean square error estimate of 9.8% canopy mortality, a mean absolute error of 7.6% and an R2 of 0.82. The results demonstrate that a model of percent canopy mortality as a continuous variable can be developed to identify a gradient of mountain pine beetle severity on the

  8. Before Cumulative Culture : The Evolutionary Origins of Overimitation and Shared Intentionality. (United States)

    Shipton, Ceri; Nielsen, Mark


    In the 7 million years or so since humans shared a common ancestor with chimpanzees we have colonized more of the planet's terrestrial habitat than any other mammalian species and come to account for more biomass than all other terrestrial vertebrates combined. Chimpanzees, in contrast to and under pressure from ourselves, have veered toward extinction. There are multiple reasons for the stark evolutionary trajectories humans and chimpanzees have taken. Recent theoretical and empirical interest has focused on the emergence of cumulative culture whereby technological innovations are progressively incorporated into a population's stock of skills and knowledge, generating ever more sophisticated repertoires. Here we look at the role of high-fidelity imitation and intention-reading in the establishment of cumulative culture. By focusing on the lithic record, we aim to identify when in our evolutionary history these skills became part of our ancestors' behavioral repertoire. We argue that evidence of cooperative construction in stone tool manufacture, along with speculation regarding changes to the mirror neurone system, hint at the foundations of overimitation and shared intentionality around 2 million years ago. However, these are not the only ingredients of cumulative culture, which is why we do not see convincing evidence for it until slightly more than a million years later.

  9. Cumulative radiation exposure in children with cystic fibrosis.

    LENUS (Irish Health Repository)

    O'Reilly, R


    This retrospective study calculated the cumulative radiation dose for children with cystic fibrosis (CF) attending a tertiary CF centre. Information on 77 children with a mean age of 9.5 years, a follow up time of 658 person years and 1757 studies including 1485 chest radiographs, 215 abdominal radiographs and 57 computed tomography (CT) scans, of which 51 were thoracic CT scans, were analysed. The average cumulative radiation dose was 6.2 (0.04-25) mSv per CF patient. Cumulative radiation dose increased with increasing age and number of CT scans and was greater in children who presented with meconium ileus. No correlation was identified between cumulative radiation dose and either lung function or patient microbiology cultures. Radiation carries a risk of malignancy and children are particularly susceptible. Every effort must be made to avoid unnecessary radiation exposure in these patients whose life expectancy is increasing.

  10. Cumulative Environmental Impacts: Science and Policy to Protect Communities. (United States)

    Solomon, Gina M; Morello-Frosch, Rachel; Zeise, Lauren; Faust, John B


    Many communities are located near multiple sources of pollution, including current and former industrial sites, major roadways, and agricultural operations. Populations in such locations are predominantly low-income, with a large percentage of minorities and non-English speakers. These communities face challenges that can affect the health of their residents, including limited access to health care, a shortage of grocery stores, poor housing quality, and a lack of parks and open spaces. Environmental exposures may interact with social stressors, thereby worsening health outcomes. Age, genetic characteristics, and preexisting health conditions increase the risk of adverse health effects from exposure to pollutants. There are existing approaches for characterizing cumulative exposures, cumulative risks, and cumulative health impacts. Although such approaches have merit, they also have significant constraints. New developments in exposure monitoring, mapping, toxicology, and epidemiology, especially when informed by community participation, have the potential to advance the science on cumulative impacts and to improve decision making.

  11. Online Scheduling in Manufacturing A Cumulative Delay Approach

    CERN Document Server

    Suwa, Haruhiko


    Online scheduling is recognized as the crucial decision-making process of production control at a phase of “being in production" according to the released shop floor schedule. Online scheduling can be also considered as one of key enablers to realize prompt capable-to-promise as well as available-to-promise to customers along with reducing production lead times under recent globalized competitive markets. Online Scheduling in Manufacturing introduces new approaches to online scheduling based on a concept of cumulative delay. The cumulative delay is regarded as consolidated information of uncertainties under a dynamic environment in manufacturing and can be collected constantly without much effort at any points in time during a schedule execution. In this approach, the cumulative delay of the schedule has the important role of a criterion for making a decision whether or not a schedule revision is carried out. The cumulative delay approach to trigger schedule revisions has the following capabilities for the ...

  12. Pesticide Cumulative Risk Assessment: Framework for Screening Analysis (United States)

    This document provides guidance on how to screen groups of pesticides for cumulative evaluation using a two-step approach: begin with evaluation of available toxicological information and, if necessary, follow up with a risk-based screening approach.

  13. Peer tutors as learning and teaching partners: a cumulative ...

    African Journals Online (AJOL)

    ... paper explores the kinds of development in tutors' thinking and action that are possible when training and development is theoretically informed, coherent, and oriented towards improving practice. Keywords: academic development, academic literacies, cumulative learning, higher education, peer tutoring, writing centres.

  14. Cumulative query method for influenza surveillance using search engine data. (United States)

    Seo, Dong-Woo; Jo, Min-Woo; Sohn, Chang Hwan; Shin, Soo-Yong; Lee, JaeHo; Yu, Maengsoo; Kim, Won Young; Lim, Kyoung Soo; Lee, Sang-Il


    Internet search queries have become an important data source in syndromic surveillance system. However, there is currently no syndromic surveillance system using Internet search query data in South Korea. The objective of this study was to examine correlations between our cumulative query method and national influenza surveillance data. Our study was based on the local search engine, Daum (approximately 25% market share), and influenza-like illness (ILI) data from the Korea Centers for Disease Control and Prevention. A quota sampling survey was conducted with 200 participants to obtain popular queries. We divided the study period into two sets: Set 1 (the 2009/10 epidemiological year for development set 1 and 2010/11 for validation set 1) and Set 2 (2010/11 for development Set 2 and 2011/12 for validation Set 2). Pearson's correlation coefficients were calculated between the Daum data and the ILI data for the development set. We selected the combined queries for which the correlation coefficients were .7 or higher and listed them in descending order. Then, we created a cumulative query method n representing the number of cumulative combined queries in descending order of the correlation coefficient. In validation set 1, 13 cumulative query methods were applied, and 8 had higher correlation coefficients (min=.916, max=.943) than that of the highest single combined query. Further, 11 of 13 cumulative query methods had an r value of ≥.7, but 4 of 13 combined queries had an r value of ≥.7. In validation set 2, 8 of 15 cumulative query methods showed higher correlation coefficients (min=.975, max=.987) than that of the highest single combined query. All 15 cumulative query methods had an r value of ≥.7, but 6 of 15 combined queries had an r value of ≥.7. Cumulative query method showed relatively higher correlation with national influenza surveillance data than combined queries in the development and validation set.

  15. REE and Isotopic Compositions of Lunar Basalts Demonstrate Partial Melting of Hybridized Mantle Sources after Cumulate Overturn is Required (United States)

    Dygert, N. J.; Liang, Y.


    Lunar basalts maintain an important record of the composition of the lunar interior. Much of our understanding of the Moon's early evolution comes from studying their petrogenesis. Recent experimental work has advanced our knowledge of major and trace element fractionation during lunar magma ocean (LMO) crystallization [e.g., 1-3], which produced heterogeneous basalt sources in the Moon's mantle. With the new experimental constraints, we can evaluate isotopic and trace element signatures in lunar basalts in unprecedented detail, refining inferences about the Moon's dynamic history. Two petrogenetic models are invoked to explain the compositions of the basalts. The assimilation model argues they formed as primitive melts of early LMO cumulates that assimilated late LMO cumulates as they migrated upward. The cumulate overturn model argues that dense LMO cumulates sank into the lunar interior, producing hybridized sources that melted to form the basalts. Here we compare predicted Ce/Yb and Hf and Nd isotopes of partial melts of LMO cumulates with measured compositions of lunar basalts to evaluate whether they could have formed by end-member petrogenetic models. LMO crystallization models suggest all LMO cumulates have chondrite normalized Ce/Yb 1.5; these could not have formed by assimilation of any LMO cumulate or residual liquid (or KREEP basalt, which has isotopically negative ɛNd and ɛHf). In contrast, basalt REE patterns and isotopes can easily be modeled assuming partial melting of hybridized mantle sources, indicating overturn may be required. A chemical requirement for overturn independently confirms that late LMO cumulates are sufficiently low in viscosity to sink into the lunar interior, as suggested by recent rock deformation experiments [4]. Overturned, low viscosity late LMO cumulates would be relatively stable around the core [5]. High Ce/Yb basalts require that overturned cumulates were mixed back into the overlying mantle by convection within a few

  16. Cumulative Risk and Continuity in Nonparental Care from Infancy to Early Adolescence. (United States)

    Colwell, Malinda J; Pettit, Gregory S; Meece, Darrell; Bates, John E; Dodge, Kenneth A


    Variations in amounts of nonparental care across infancy, preschool, early elementary school, and early adolescence were examined in a longitudinal sample (N = 438). Of interest was (a) continuity in use of the different arrangements, (b) whether the arrangements were additively and cumulatively associated with children's externalizing behavior problems, and (c) whether predictive relations were accounted for by social-ecological (socioeconomic status, mothers' employment status, marital status) and social-experiential (parenting quality, exposure to aggressive peers) factors. Correlations among overall amounts of care provided little evidence of cross-time continuity. Consistent with the cumulative risk perspective, Grade 1 self-care and Grade 6 unsupervised peer contact incrementally predicted Grade 6 externalizing problems. Most of the predictive associations were accounted for by family background and social relationship factors.

  17. Cumulative glycemia and microangiopathy in subjects with impaired glucose regulation in the Inter99 study

    DEFF Research Database (Denmark)

    Munch, Inger Christine; Larsen, Michael; Kessel, Line


    .8% (CI(95) 6.8-17.1%) in subjects with screen-detected diabetes compared to normoglycemic subjects, adjusted for age, sex, and smoking. The prevalences of microalbuminuria and retinopathy were significantly increased in subjects with screen-detected diabetes after adjusting for age, sex and systolic...... in subjects with abnormal glucose metabolism, most prominently in subjects with IFG+IGT and in subjects with screen-detected diabetes. These results provide the first objective evidence that cumulative glycemic load is increased at the earliest stage of impaired glucose regulation.......AIMS: To assess cumulative glycemia, microvascular characteristics, and associated risk factors for diabetes in subjects with impaired glucose regulation. METHODS: Cross-sectional, population-based study comprising systemic characteristics in 6487 participants and ocular characteristics in 970...

  18. Are adolescents more vulnerable to drug addiction than adults? Evidence from animal models. (United States)

    Schramm-Sapyta, Nicole L; Walker, Q David; Caster, Joseph M; Levin, Edward D; Kuhn, Cynthia M


    Epidemiological evidence suggests that people who begin experimenting with drugs of abuse during early adolescence are more likely to develop substance use disorders (SUDs), but this correlation does not guarantee causation. Animal models, in which age of onset can be tightly controlled, offer a platform for testing causality. Many animal models address drug effects that might promote or discourage drug intake and drug-induced neuroplasticity. We have reviewed the preclinical literature to investigate whether adolescent rodents are differentially sensitive to rewarding, reinforcing, aversive, locomotor, and withdrawal-induced effects of drugs of abuse. The rodent model literature consistently suggests that the balance of rewarding and aversive effects of drugs of abuse is tipped toward reward in adolescence. However, increased reward does not consistently lead to increased voluntary intake: age effects on voluntary intake are drug and method specific. On the other hand, adolescents are consistently less sensitive to withdrawal effects, which could protect against compulsive drug seeking. Studies examining neuronal function have revealed several age-related effects but have yet to link these effects to vulnerability to SUDs. Taken together, the findings suggest factors which may promote recreational drug use in adolescents, but evidence relating to pathological drug-seeking behavior is lacking. A call is made for future studies to address this gap using behavioral models of pathological drug seeking and for neurobiologic studies to more directly link age effects to SUD vulnerability.

  19. Model comparison using Bayes factors computed from MCMC samples: evidence for four planets orbiting GJ 876 (United States)

    Nelson, Benjamin Earl; Robertson, Paul; Pritchard, Seth


    As planet hunters are pushing radial velocity (RV) precision to the sub-meter per second regime, it is becoming increasingly necessary to disentangle periodic signals of stellar magnetic activity from those of real exoplanets. Statistically robust model comparison algorithms are key in addressing this challenge and complementing more traditional observationally focused methods of planet validation. We develop an algorithm to compute the fully marginalized likelihood (FML, i.e. Bayesian evidence) of a finite set of high-dimensional (~30-40 parameter) models, whose ratios yield Bayes factors for model comparison. The code combines a simple importance sampling algorithm with a Markov chain Monte Carlo posterior sample to produce an accurate estimate of the FML. We apply this algorithm to RV observations of the GJ 876, an M dwarf harboring four supposed planets, three of which are undergoing strong dynamical interactions. Our analysis finds overwhelming Bayesian evidence for the inner three planets and a fourth periodicity due to either the putative planet "e" or stellar activity. Combining our Doppler analysis with a separate stellar activity analysis favors the four-planet model.

  20. Model validation and the role of the proposed Rock Characterisation Facility at Sellafield. Proof of evidence

    International Nuclear Information System (INIS)

    Wallace, H.


    Proof of Evidence is given by an expert witness on behalf of Greenpeace Ltd as part of their submission to a Planning Inquiry in 1995 hearing the application of UK Nirex Ltd for permission to construct an underground Rock Characterisation Facility (RCF) at a site near Sellafield. The RCF is part of an investigation by Nirex into a suitable site for the disposal of radioactive waste. An examination of the groundwater flow models used by Nirex and the procedure for their validation have led to the following conclusions: no evidence has been presented by Nirex to show that the construction of the RCF will improve the confidence they claim to have in the site; the prospects are slim for validating the models of present groundwater flow so that they satisfy the criteria to meet the risk target; it is extremely unlikely that results from the RCF will increase confidence in a safety assessment of this site; all the evidence available to date suggests that the risk assessment is not, and will not become, robust to variations in flux through the repository. (1 figure; 8 references). (UK)

  1. A diffusion decision model analysis of evidence variability in the lexical decision task. (United States)

    Tillman, Gabriel; Osth, Adam F; van Ravenzwaaij, Don; Heathcote, Andrew


    The lexical-decision task is among the most commonly used paradigms in psycholinguistics. In both the signal-detection theory and Diffusion Decision Model (DDM; Ratcliff, Gomez, & McKoon, Psychological Review, 111, 159-182, 2004) frameworks, lexical-decisions are based on a continuous source of word-likeness evidence for both words and non-words. The Retrieving Effectively from Memory model of Lexical-Decision (REM-LD; Wagenmakers et al., Cognitive Psychology, 48(3), 332-367, 2004) provides a comprehensive explanation of lexical-decision data and makes the prediction that word-likeness evidence is more variable for words than non-words and that higher frequency words are more variable than lower frequency words. To test these predictions, we analyzed five lexical-decision data sets with the DDM. For all data sets, drift-rate variability changed across word frequency and non-word conditions. For the most part, REM-LD's predictions about the ordering of evidence variability across stimuli in the lexical-decision task were confirmed.

  2. Barriers and facilitators to replicating an evidence-based palliative care model. (United States)

    Davis, E Maxwell; Jamison, Paula; Brumley, Richard; Enguídanos, Susan


    Recognition of the difficulties involved in replicating evidence- based interventions is well documented in the literature within the medical field. Promising research findings are often not translated into practice, and if they are, there is a significant time gap between study conclusion and practice adoption. The purpose of this article is to describe the barriers and facilitators encountered by two managed care organizations while replicating an evidence-based end of life in-home palliative care model. Using Diffusion of Innovation Theory as a theoretical framework, results from focus groups and interviews with the project's clinical, administrative and research teams are presented and recommendations made for improving translational efforts. The process of replicating the end of life in-home palliative care model clearly illustrated the key elements required for successfully diffusing innovation. These key elements include marketing and communication, leadership, organizational support and training and mentorship. This qualitative process study provides clear, real world perspectives of the myriad of challenges encountered in replicating an evidence-based project.

  3. Childhood Cumulative Risk Exposure and Adult Amygdala Volume and Function. (United States)

    Evans, Gary W; Swain, James E; King, Anthony P; Wang, Xin; Javanbakht, Arash; Ho, S Shaun; Angstadt, Michael; Phan, K Luan; Xie, Hong; Liberzon, Israel


    Considerable work indicates that early cumulative risk exposure is aversive to human development, but very little research has examined the neurological underpinnings of these robust findings. This study investigates amygdala volume and reactivity to facial stimuli among adults (mean 23.7 years of age, n = 54) as a function of cumulative risk exposure during childhood (9 and 13 years of age). In addition, we test to determine whether expected cumulative risk elevations in amygdala volume would mediate functional reactivity of the amygdala during socioemotional processing. Risks included substandard housing quality, noise, crowding, family turmoil, child separation from family, and violence. Total and left hemisphere adult amygdala volumes were positively related to cumulative risk exposure during childhood. The links between childhood cumulative risk exposure and elevated amygdala responses to emotionally neutral facial stimuli in adulthood were mediated by the corresponding amygdala volumes. Cumulative risk exposure in later adolescence (17 years of age), however, was unrelated to subsequent adult amygdala volume or function. Physical and socioemotional risk exposures early in life appear to alter amygdala development, rendering adults more reactive to ambiguous stimuli such as neutral faces. These stress-related differences in childhood amygdala development might contribute to the well-documented psychological distress as a function of early risk exposure. © 2015 Wiley Periodicals, Inc.

  4. Analysis of model implied volatility for jump diffusion models. Empirical evidence from the Nordpool market

    International Nuclear Information System (INIS)

    Nomikos, Nikos K.; Soldatos, Orestes A.


    In this paper we examine the importance of mean reversion and spikes in the stochastic behaviour of the underlying asset when pricing options on power. We propose a model that is flexible in its formulation and captures the stylized features of power prices in a parsimonious way. The main feature of the model is that it incorporates two different speeds of mean reversion to capture the differences in price behaviour between normal and spiky periods. We derive semi-closed form solutions for European option prices using transform analysis and then examine the properties of the implied volatilities that the model generates. We find that the presence of jumps generates prominent volatility skews which depend on the sign of the mean jump size. We also show that mean reversion reduces the volatility smile as time to maturity increases. In addition, mean reversion induces volatility skews particularly for ITM options, even in the absence of jumps. Finally, jump size volatility and jump intensity mainly affect the kurtosis and thus the curvature of the smile with the former having a more important role in making the volatility smile more pronounced and thus increasing the kurtosis of the underlying price distribution. (author)

  5. Calibration of complex models through Bayesian evidence synthesis: a demonstration and tutorial (United States)

    Jackson, Christopher; Jit, Mark; Sharples, Linda; DeAngelis, Daniela


    Summary Decision-analytic models must often be informed using data which are only indirectly related to the main model parameters. The authors outline how to implement a Bayesian synthesis of diverse sources of evidence to calibrate the parameters of a complex model. A graphical model is built to represent how observed data are generated from statistical models with unknown parameters, and how those parameters are related to quantities of interest for decision-making. This forms the basis of an algorithm to estimate a posterior probability distribution, which represents the updated state of evidence for all unknowns given all data and prior beliefs. This process calibrates the quantities of interest against data, and at the same time, propagates all parameter uncertainties to the results used for decision-making. To illustrate these methods, the authors demonstrate how a previously-developed Markov model for the progression of human papillomavirus (HPV16) infection was rebuilt in a Bayesian framework. Transition probabilities between states of disease severity are inferred indirectly from cross-sectional observations of prevalence of HPV16 and HPV16-related disease by age, cervical cancer incidence, and other published information. Previously, a discrete collection of plausible scenarios was identified, but with no further indication of which of these are more plausible. Instead, the authors derive a Bayesian posterior distribution, in which scenarios are implicitly weighted according to how well they are supported by the data. In particular, we emphasise the appropriate choice of prior distributions and checking and comparison of fitted models. PMID:23886677

  6. Reviewing the evidence to inform the population of cost-effectiveness models within health technology assessments. (United States)

    Kaltenthaler, Eva; Tappenden, Paul; Paisley, Suzy


    Health technology assessments (HTAs) typically require the development of a cost-effectiveness model, which necessitates the identification, selection, and use of other types of information beyond clinical effectiveness evidence to populate the model parameters. The reviewing activity associated with model development should be transparent and reproducible but can result in a tension between being both timely and systematic. Little procedural guidance exists in this area. The purpose of this article was to provide guidance, informed by focus groups, on what might constitute a systematic and transparent approach to reviewing information to populate model parameters. A focus group series was held with HTA experts in the United Kingdom including systematic reviewers, information specialists, and health economic modelers to explore these issues. Framework analysis was used to analyze the qualitative data elicited during focus groups. Suggestions included the use of rapid reviewing methods and the need to consider the trade-off between relevance and quality. The need for transparency in the reporting of review methods was emphasized. It was suggested that additional attention should be given to the reporting of parameters deemed to be more important to the model or where the preferred decision regarding the choice of evidence is equivocal. These recommendations form part of a Technical Support Document produced for the National Institute for Health and Clinical Excellence Decision Support Unit in the United Kingdom. It is intended that these recommendations will help to ensure a more systematic, transparent, and reproducible process for the review of model parameters within HTA. Copyright © 2013 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.


    African Journals Online (AJOL)


    Oct 6, 2005 ... Second order covariance analysis of the bilinear mult~plicative seasonal ARlMA (O,d,O) -x (1 ,D,I), time series model ... We will also investigate the use of the covariance structure and third order ..... blaving determined s and initial estimate of a, we now consider how to obtain the 'initial estimates of P, y and.

  8. Domain-general biases in spatial localization: Evidence against a distorted body model hypothesis. (United States)

    Medina, Jared; Duckett, Caitlin


    A number of studies have proposed the existence of a distorted body model of the hand. Supporting this hypothesis, judgments of the location of hand landmarks without vision are characterized by consistent distortions-wider knuckle and shorter finger lengths. We examined an alternative hypothesis in which these biases are caused by domain-general mechanisms, in which participants overestimate the distance between consecutive localization judgments that are spatially close. To do so, we examined performance on a landmark localization task with the hand (Experiments 1-3) using a lag-1 analysis. We replicated the widened knuckle judgments in previous studies. Using the lag-1 analysis, we found evidence for a constant overestimation bias along the mediolateral hand axis, such that consecutive stimuli were perceived as farther apart when they were closer (e.g., index-middle knuckle) versus farther (index-pinky) in space. Controlling for this bias, we found no evidence for a distorted body model along the mediolateral hand axis. To examine whether similar widening biases could be found with noncorporeal stimuli, we asked participants to localize remembered dots on a hand-like array (Experiments 4-5). Mean localization judgments were wider than actual along the primary array axis, similar to previous work with hands. As with proprioceptively defined stimuli, we found that this widening was primarily due to a constant overestimation bias. These results provide substantial evidence against a distorted body model hypothesis and support a domain-general model in which responses are biased away from the uncertainty distribution of the previous trial, leading to a constant overestimation bias. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  9. Beyond Cumulative Risk: A Dimensional Approach to Childhood Adversity. (United States)

    McLaughlin, Katie A; Sheridan, Margaret A


    Children who have experienced environmental adversity-such as abuse, neglect, or poverty-are more likely to develop physical and mental health problems, perform poorly at school, and have difficulties in social relationships than children who have not encountered adversity. What is less clear is how and why adverse early experiences exert such a profound influence on children's development. Identifying developmental processes that are disrupted by adverse early environments is the key to developing better intervention strategies for children who have experienced adversity. Yet, much existing research relies on a cumulative risk approach that is unlikely to reveal these mechanisms. This approach tallies the number of distinct adversities experienced to create a risk score. This risk score fails to distinguish between distinct types of environmental experience, implicitly assuming that very different experiences influence development through the same underlying mechanisms. We advance an alternative model. This novel approach conceptualizes adversity along distinct dimensions, emphasizes the central role of learning mechanisms, and distinguishes between different forms of adversity that might influence learning in distinct ways. A key advantage of this approach is that learning mechanisms provide clear targets for interventions aimed at preventing negative developmental outcomes in children who have experienced adversity.

  10. Nrf2 Signaling and the Slowed Aging Phenotype: Evidence from Long-Lived Models

    Directory of Open Access Journals (Sweden)

    Danielle R. Bruns


    Full Text Available Studying long-lived animals provides novel insight into shared characteristics of aging and represents a unique model to elucidate approaches to prevent chronic disease. Oxidant stress underlies many chronic diseases and resistance to stress is a potential mechanism governing slowed aging. The transcription factor nuclear factor (erythroid-derived 2-like 2 is the “master regulator” of cellular antioxidant defenses. Nrf2 is upregulated by some longevity promoting interventions and may play a role in regulating species longevity. However, Nrf2 expression and activity in long-lived models have not been well described. Here, we review evidence for altered Nrf2 signaling in a variety of slowed aging models that accomplish lifespan extension via pharmacological, nutritional, evolutionary, genetic, and presumably epigenetic means.

  11. Facilitating Lewin's change model with collaborative evaluation in promoting evidence based practices of health professionals. (United States)

    Manchester, Julianne; Gray-Miceli, Deanna L; Metcalf, Judith A; Paolini, Charlotte A; Napier, Anne H; Coogle, Constance L; Owens, Myra G


    Evidence based practices (EBPs) in clinical settings interact with and adapt to host organizational characteristics. The contextual factors themselves, surrounding health professions' practices, also adapt as practices become sustained. The authors assert the need for better planning models toward these contextual factors, the influence of which undergird a well-documented science to practice gap in literature on EBPs. The mechanism for EBP planners to anticipate contextual effects as programs Unfreeze their host settings, create Movement, and become Refrozen (Lewin, 1951) is present in Lewin's 3-step change model. Planning for contextual change appears equally important as planning for the actual practice outcomes among providers and patients. Two case studies from a Geriatric Education Center network will illustrate the synthesis of Lewin's three steps with collaborative evaluation principles. The use of the model may become an important tool for continuing education evaluators or organizations beginning a journey toward EBP demonstration projects in clinical settings. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Irrelevant sensory stimuli interfere with working memory storage: evidence from a computational model of prefrontal neurons. (United States)

    Bancroft, Tyler D; Hockley, William E; Servos, Philip


    The encoding of irrelevant stimuli into the memory store has previously been suggested as a mechanism of interference in working memory (e.g., Lange & Oberauer, Memory, 13, 333-339, 2005; Nairne, Memory & Cognition, 18, 251-269, 1990). Recently, Bancroft and Servos (Experimental Brain Research, 208, 529-532, 2011) used a tactile working memory task to provide experimental evidence that irrelevant stimuli were, in fact, encoded into working memory. In the present study, we replicated Bancroft and Servos's experimental findings using a biologically based computational model of prefrontal neurons, providing a neurocomputational model of overwriting in working memory. Furthermore, our modeling results show that inhibition acts to protect the contents of working memory, and they suggest a need for further experimental research into the capacity of vibrotactile working memory.

  13. Gene × Environment Interactions in Schizophrenia: Evidence from Genetic Mouse Models

    Directory of Open Access Journals (Sweden)

    Paula Moran


    Full Text Available The study of gene × environment, as well as epistatic interactions in schizophrenia, has provided important insight into the complex etiopathologic basis of schizophrenia. It has also increased our understanding of the role of susceptibility genes in the disorder and is an important consideration as we seek to translate genetic advances into novel antipsychotic treatment targets. This review summarises data arising from research involving the modelling of gene × environment interactions in schizophrenia using preclinical genetic models. Evidence for synergistic effects on the expression of schizophrenia-relevant endophenotypes will be discussed. It is proposed that valid and multifactorial preclinical models are important tools for identifying critical areas, as well as underlying mechanisms, of convergence of genetic and environmental risk factors, and their interaction in schizophrenia.

  14. Gene × Environment Interactions in Schizophrenia: Evidence from Genetic Mouse Models. (United States)

    Moran, Paula; Stokes, Jennifer; Marr, Julia; Bock, Gavin; Desbonnet, Lieve; Waddington, John; O'Tuathaigh, Colm


    The study of gene × environment, as well as epistatic interactions in schizophrenia, has provided important insight into the complex etiopathologic basis of schizophrenia. It has also increased our understanding of the role of susceptibility genes in the disorder and is an important consideration as we seek to translate genetic advances into novel antipsychotic treatment targets. This review summarises data arising from research involving the modelling of gene × environment interactions in schizophrenia using preclinical genetic models. Evidence for synergistic effects on the expression of schizophrenia-relevant endophenotypes will be discussed. It is proposed that valid and multifactorial preclinical models are important tools for identifying critical areas, as well as underlying mechanisms, of convergence of genetic and environmental risk factors, and their interaction in schizophrenia.

  15. Describing phytotoxic effects on cumulative germination


    Dias, L.S.


    Phytotoxic studies strongly depend on evaluation of germination responses, which implies the need for adequate procedures to account for distinct aspects of the germinative process. For this, indices, comparisons among treatments at various times, and model fitting have been proposed. The objective of this work is to compare the three approaches and select the one providing greater insight and precision. Speed of germination, speed of accumulated germination, the coefficient of the rate of ge...

  16. A probabilistic analysis of cumulative carbon emissions and long-term planetary warming (United States)

    Fyke, Jeremy; Damon Matthews, H.


    Efforts to mitigate and adapt to long-term climate change could benefit greatly from probabilistic estimates of cumulative carbon emissions due to fossil fuel burning and resulting CO2-induced planetary warming. Here we demonstrate the use of a reduced-form model to project these variables. We performed simulations using a large-ensemble framework with parametric uncertainty sampled to produce distributions of future cumulative emissions and consequent planetary warming. A hind-cast ensemble of simulations captured 1980-2012 historical CO2 emissions trends and an ensemble of future projection simulations generated a distribution of emission scenarios that qualitatively resembled the suite of Representative and Extended Concentration Pathways. The resulting cumulative carbon emission and temperature change distributions are characterized by 5-95th percentile ranges of 0.96-4.9 teratonnes C (Tt C) and 1.4 °C-8.5 °C, respectively, with 50th percentiles at 3.1 Tt C and 4.7 °C. Within the wide range of policy-related parameter combinations that produced these distributions, we found that low-emission simulations were characterized by both high carbon prices and low costs of non-fossil fuel energy sources, suggesting the importance of these two policy levers in particular for avoiding dangerous levels of climate warming. With this analysis we demonstrate a probabilistic approach to the challenge of identifying strategies for limiting cumulative carbon emissions and assessing likelihoods of surpassing dangerous temperature thresholds.

  17. Cumulative violence exposure, emotional nonacceptance, and mental health symptoms in a community sample of women. (United States)

    Sundermann, Jane M; Chu, Ann T; DePrince, Anne P


    Women exposed to more types of violence (e.g., emotional, physical, or sexual violence)--referred to here as cumulative violence exposure--are at risk for more severe mental health symptoms compared to women who are exposed to a single type of violence or no violence. Women exposed to violence may also experience greater emotional nonacceptance compared to women with no exposure to violence. Emotional nonacceptance refers to an unwillingness to experience emotional states, including cognitive and behavioral attempts to avoid experiences of emotion. Given the links between cumulative violence exposure, emotional nonacceptance, and mental health symptoms among female victims of violence, the current study tested victims' emotional nonacceptance as a partial mediator between cumulative violence exposure and the severity of 3 types of symptoms central to complex trauma responses: depression, dissociation, and posttraumatic stress disorder (PTSD) symptoms. A non-treatment-seeking community sample of women (N = 89; M age = 30.70 years) completed self-report questionnaires and interviews. Bootstrap procedures were then used to test 3 mediation models for the separate predictions of depression, dissociation, and PTSD symptoms. Results supported our hypotheses that emotional nonacceptance would mediate the relationship between women's cumulative violence exposure and severity for all symptom types. The current findings highlight the role that emotional nonacceptance may play in the development of mental health symptoms for chronically victimized women and point to the need for longitudinal research in such populations.

  18. The Amphiolite Layers In The Cumulate Gabbros, (Northern-Turkey) (United States)

    Özkan, Mutlu; Faruk Çelik, Ömer; Altıntaş, İsmail Emir; Sherlock, Sarah; Chelle-Michou, Cyril; Marzoli, Andrea; Ulianov, Alexey; Melih Çörtük, Rahmi; Topuz, Gültekin


    The Early-Middle Jurassic SSZ type dismembered ophiolite sequence, which is remnants of the Tethyan oceanic lithosphere, crop out in the accretionary complex around Tokat-Çamlıbel region (Northern Turkey). The main lithology of the ophiolite sequence are cumulate gabbros, isotropic gabbros and basalts. The amphibolite layers, which their thickness are up to 2 m, are observed in the cumulate gabbros. In this study, we aim to discuss a possible formation mechanism of the amphibolitic rocks in the cumulate gabbros, based on the field, mineralogical, geochemical and geochronological data. The cumulate gabbros (olivine-gabbro, gabbro-norite and gabbro) have generally well developed magmatic layers and they show cumulate texture. They are cross cut by pegmatite gabbros, dolerites and plagiogranite dikes. In terms of the mechanism of formation, the amphibolite layers in the cumulate gabbros are different from dolerite, pegmatite gabbro and plagiogranite dikes crosscutting the cumulate gabbros. Although the cumulate gabbros, the mafic and felsic dikes have not undergone any metamorphism (except the hydrothermal metamorphism), the amphibolite layers show well developed foliation and banded structure. Moreover, field and petrographic observations showed that the amphibolitic rocks were highly subjected to shearing. The amphibolitic rocks are mainly composed of magnesio-hornblende + plagioclase (andesine), ± biotite and opaque minerals and they exhibit nematoblastic texture. The amphibolite layers in the cumulate gabbros are crosscut by the plagiogranite dikes. The plagiogranites consist mainly of quartz, plagioclase, biotite and opaque minerals and they show granular texture. Undulose extinction and sub-grain formation in quartz minerals indicate to the presence of deformation phase affecting the plagiogranite dikes. LA-ICP-MS dating on zircon from plagiogranite dikes which is cross-cutting of the amphibolite layers, yielded Middle Jurassic ages. 40Ar/39Ar dating of

  19. The Quest for Evidence for Proton Therapy: Model-Based Approach and Precision Medicine

    Energy Technology Data Exchange (ETDEWEB)

    Widder, Joachim, E-mail: [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Schaaf, Arjen van der [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Lambin, Philippe [Department of Radiation Oncology, School for Oncology and Developmental Biology (GROW), Maastricht University Medical Center, Maastricht (Netherlands); Marijnen, Corrie A.M. [Department of Radiation Oncology, Leiden University Medical Center, Leiden (Netherlands); Pignol, Jean-Philippe [Department of Radiation Oncology, Erasmus Medical Center Cancer Institute, Rotterdam (Netherlands); Rasch, Coen R. [Department of Radiation Oncology, Academic Medical Center, Amsterdam (Netherlands); Slotman, Ben J. [Department of Radiation Oncology, VU Medical Center, Amsterdam (Netherlands); Verheij, Marcel [Department of Radiation Oncology, Netherlands Cancer Institute, Amsterdam (Netherlands); Langendijk, Johannes A. [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands)


    Purpose: Reducing dose to normal tissues is the advantage of protons versus photons. We aimed to describe a method for translating this reduction into a clinically relevant benefit. Methods and Materials: Dutch scientific and health care governance bodies have recently issued landmark reports regarding generation of relevant evidence for new technologies in health care including proton therapy. An approach based on normal tissue complication probability (NTCP) models has been adopted to select patients who are most likely to experience fewer (serious) adverse events achievable by state-of-the-art proton treatment. Results: By analogy with biologically targeted therapies, the technology needs to be tested in enriched cohorts of patients exhibiting the decisive predictive marker: difference in normal tissue dosimetric signatures between proton and photon treatment plans. Expected clinical benefit is then estimated by virtue of multifactorial NTCP models. In this sense, high-tech radiation therapy falls under precision medicine. As a consequence, randomizing nonenriched populations between photons and protons is predictably inefficient and likely to produce confusing results. Conclusions: Validating NTCP models in appropriately composed cohorts treated with protons should be the primary research agenda leading to urgently needed evidence for proton therapy.

  20. Teaching evidence-based practice: developing a curriculum model to foster evidence-based practice in undergraduate student nurses. (United States)

    Finotto, Stefano; Carpanoni, Marika; Turroni, Elena Casadei; Camellini, Riccarda; Mecugni, Daniela


    For the nature of the Evidence-Based Practice (EBP) and its relevance to nursing, the skills that it requires should be a component in the basic Nursing degree courses. For this reason, the EBP process should be introduced early on in nursing education to develop students' independence and ability to self-learning. the aim of this study is to describe the perception that newly graduated nurses have relative to the benefits of the skills learned during the laboratory's three-year EBP in consideration of the construction of the thesis, the research of evidence and usefulness of the EBP process for the development of their professional career. A descriptive study with a sample of 300 newly graduated nurses from the Degree Course in Nursing of the University of Modena and Reggio Emilia, venue of Reggio Emilia. The data collection instrument was an anonymous questionnaire. It was possible to answer through a 10 Likert scale. The sample considers effective the research of evidence carried out (mean 6, SD 2), related to the problems of patients (mean 7, SD 2); the sample considered the skills acquired during the laboratory's three-year EBP to be useful for career development (mean 7, SD 2). the decision to include the laboratory's three-year EBP in the curriculum of the Nursing degree promotes the development of skills relating to the use of the EBP process, competence that in the literature is indicated as one of the core competencies that all health professionals should develop and maintain throughout their professional career. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Neural network model for cumulative grade point average (CGPA ...

    African Journals Online (AJOL)

    One of the major tasks performed in any institutions of higher learning is the assessment of students' performance by ways of conducting Tests and Examinations on semester-by-semester basis. Following the examination to be written by student(s), the result would be computed using an appropriate grades and grade point, ...

  2. On cumulative process model and its statistical analysis

    Czech Academy of Sciences Publication Activity Database

    Volf, Petr


    Roč. 36, č. 2 (2000), s. 165-176 ISSN 0023-5954 R&D Projects: GA ČR GA201/97/0354; GA ČR GA402/98/0742 Institutional research plan: AV0Z1075907 Subject RIV: BB - Applied Statistics, Operational Research

  3. A Model of Consultation in Prostate Cancer Care: Evidence From a Systematic Review. (United States)

    Paterson, Catherine; Nabi, Ghulam

    There has been an evolution of various consultation models in the literature. Men affected by prostate cancer can experience a range of unmet supportive care needs. Thus, effective consultations are paramount in the delivery of supportive care to optimize tailored self-management plans at the individual level of need. The aim of this study is to critically appraise existing models of consultation and make recommendations for a model of consultation within the scope of clinical practice for prostate cancer care. A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement Guidelines. Electronic databases were searched using a wide range of keywords and free text items to increase the sensitivity and inclusiveness of the searches. Findings were integrated in a narrative synthesis. A total of 1829 articles were retrieved and 17 papers were included. Beneficial features ranged across a number of models that included a person-centered consultation, shared management plans, and safety netting. None of the reviewed models of consultation are suitable for use in prostate cancer care because of a range of limitations and the clinical context in which models were developed. A Cancer Care Consultation Model was informed from critical appraisal of the evidence and expert clinical and service user comment. Further research is needed to empirically test consultation models in routine clinical practice, specifically for advanced cancer specialist nurses. The Prostate Cancer Model of Consultation can be used to structure clinical consultations to target self-management care plans at the individual level of need over the cancer care continuum.

  4. Evidence used in model-based economic evaluations for evaluating pharmacogenetic and pharmacogenomic tests: a systematic review protocol. (United States)

    Peters, Jaime L; Cooper, Chris; Buchanan, James


    Decision models can be used to conduct economic evaluations of new pharmacogenetic and pharmacogenomic tests to ensure they offer value for money to healthcare systems. These models require a great deal of evidence, yet research suggests the evidence used is diverse and of uncertain quality. By conducting a systematic review, we aim to investigate the test-related evidence used to inform decision models developed for the economic evaluation of genetic tests. We will search electronic databases including MEDLINE, EMBASE and NHS EEDs to identify model-based economic evaluations of pharmacogenetic and pharmacogenomic tests. The search will not be limited by language or date. Title and abstract screening will be conducted independently by 2 reviewers, with screening of full texts and data extraction conducted by 1 reviewer, and checked by another. Characteristics of the decision problem, the decision model and the test evidence used to inform the model will be extracted. Specifically, we will identify the reported evidence sources for the test-related evidence used, describe the study design and how the evidence was identified. A checklist developed specifically for decision analytic models will be used to critically appraise the models described in these studies. Variations in the test evidence used in the decision models will be explored across the included studies, and we will identify gaps in the evidence in terms of both quantity and quality. The findings of this work will be disseminated via a peer-reviewed journal publication and at national and international conferences. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to

  5. An evidence-based health workforce model for primary and community care

    Directory of Open Access Journals (Sweden)

    Leach Matthew J


    Full Text Available Abstract Background The delivery of best practice care can markedly improve clinical outcomes in patients with chronic disease. While the provision of a skilled, multidisciplinary team is pivotal to the delivery of best practice care, the occupational or skill mix required to deliver this care is unclear; it is also uncertain whether such a team would have the capacity to adequately address the complex needs of the clinic population. This is the role of needs-based health workforce planning. The objective of this article is to describe the development of an evidence-informed, needs-based health workforce model to support the delivery of best-practice interdisciplinary chronic disease management in the primary and community care setting using diabetes as a case exemplar. Discussion Development of the workforce model was informed by a strategic review of the literature, critical appraisal of clinical practice guidelines, and a consensus elicitation technique using expert multidisciplinary clinical panels. Twenty-four distinct patient attributes that require unique clinical competencies for the management of diabetes in the primary care setting were identified. Patient attributes were grouped into four major themes and developed into a conceptual model: the Workforce Evidence-Based (WEB planning model. The four levels of the WEB model are (1 promotion, prevention, and screening of the general or high-risk population; (2 type or stage of disease; (3 complications; and (4 threats to self-care capacity. Given the number of potential combinations of attributes, the model can account for literally millions of individual patient types, each with a distinct clinical team need, which can be used to estimate the total health workforce requirement. Summary The WEB model was developed in a way that is not only reflective of the diversity in the community and clinic populations but also parsimonious and clear to present and operationalize. A key feature of the

  6. Evidence-based practice - an incomplete model of the relationship between theory and professional work. (United States)

    Hancock, Helen C; Easen, Patrick R


    Current day realities of diminishing resources, reductions in spending and organizational change within health care systems have resulted in an increased emphasis on a multidisciplinary team approach to quality patient care. The movement of nursing towards more autonomous practice combined with the current trend towards 'evidence-based practice' in health care demands increased accountability in clinical decision making. This paper focuses on one aspect of nurses' clinical decision making within the demands of evidence-based practice and cardiac surgery. In this field recent advances, combined with increasing demands on health care institutions, have promoted early extubation of post-operative cardiac patients. While this remains a medical role in many institutions, an increasing number of intensive care units now consider it as a nursing role. This paper explores the realities of nurses' clinical decision making through a discussion of current practice in the extubation of patients following cardiac surgery. In addition, it considers the implications of current practice for both nurse education and the continued development of clinical nursing practice. The findings indicate that evidence-based practice appears to be an incomplete model of the relationship between theory and professional work.

  7. Normative models of health technology assessment and the social production of evidence about telehealth care. (United States)

    Williams, Tracy; May, Carl; Mair, Frances; Mort, Maggie; Gask, Linda


    Telehealthcare is a rapidly growing field of clinical activity and technical development. These new technologies have caught the attention of clinicians and policy makers because they seem to offer more rapid access to specialist care, and the potential to solve structural problems around inequalities of service provision and distribution. However, as a field of clinical practice, telehealthcare has consistently been criticised because of the poor quality of the clinical and technical evidence that its proponents have marshalled. The problem of "evidence" is not a local one. In this paper, we undertake two tasks: first, we critically contrast the normative expectations of the wider field of Health Technology Assessment (HTA) with those configured within debates about Telehealthcare Evaluation; and second, we critically review models that provide structures within which the production of evidence about telehealthcare can take place. Our analysis focuses on the political projects configured within a literature aimed at stabilising evaluative knowledge production about telehealthcare in the face of substantial political and methodological problems.

  8. On the duration and intensity of cumulative advantage competitions (United States)

    Jiang, Bo; Sun, Liyuan; Figueiredo, Daniel R.; Ribeiro, Bruno; Towsley, Don


    Network growth can be framed as a competition for edges among nodes in the network. As with various other social and physical systems, skill (fitness) and luck (random chance) act as fundamental forces driving competition dynamics. In the context of networks, cumulative advantage (CA)—the rich-get-richer effect—is seen as a driving principle governing the edge accumulation process. However, competitions coupled with CA exhibit non-trivial behavior and little is formally known about duration and intensity of CA competitions. By isolating two nodes in an ideal CA competition, we provide a mathematical understanding of how CA exacerbates the role of luck in detriment of skill. We show, for instance, that when nodes start with few edges, an early stroke of luck can place the less skilled in the lead for an extremely long period of time, a phenomenon we call ‘struggle of the fittest’. We prove that duration of a simple skill and luck competition model exhibit power-law tails when CA is present, regardless of skill difference, which is in sharp contrast to the exponential tails when fitness is distinct but CA is absent. We also prove that competition intensity is always upper bounded by an exponential tail, irrespective of CA and skills. Thus, CA competitions can be extremely long (infinite mean, depending on fitness ratio) but almost never very intense. The theoretical results are corroborated by extensive numerical simulations. Our findings have important implications to competitions not only among nodes in networks but also in contexts that leverage socio-physical models embodying CA competitions.

  9. On the duration and intensity of cumulative advantage competitions

    International Nuclear Information System (INIS)

    Jiang, Bo; Towsley, Don; Sun, Liyuan; Figueiredo, Daniel R; Ribeiro, Bruno


    Network growth can be framed as a competition for edges among nodes in the network. As with various other social and physical systems, skill (fitness) and luck (random chance) act as fundamental forces driving competition dynamics. In the context of networks, cumulative advantage (CA)—the rich-get-richer effect—is seen as a driving principle governing the edge accumulation process. However, competitions coupled with CA exhibit non-trivial behavior and little is formally known about duration and intensity of CA competitions. By isolating two nodes in an ideal CA competition, we provide a mathematical understanding of how CA exacerbates the role of luck in detriment of skill. We show, for instance, that when nodes start with few edges, an early stroke of luck can place the less skilled in the lead for an extremely long period of time, a phenomenon we call ‘struggle of the fittest’. We prove that duration of a simple skill and luck competition model exhibit power-law tails when CA is present, regardless of skill difference, which is in sharp contrast to the exponential tails when fitness is distinct but CA is absent. We also prove that competition intensity is always upper bounded by an exponential tail, irrespective of CA and skills. Thus, CA competitions can be extremely long (infinite mean, depending on fitness ratio) but almost never very intense. The theoretical results are corroborated by extensive numerical simulations. Our findings have important implications to competitions not only among nodes in networks but also in contexts that leverage socio-physical models embodying CA competitions. (paper)

  10. Validity of Quinpirole Sensitization Rat Model of OCD: Linking Evidence from Animal and Clinical Studies. (United States)

    Stuchlik, Ales; Radostová, Dominika; Hatalova, Hana; Vales, Karel; Nekovarova, Tereza; Koprivova, Jana; Svoboda, Jan; Horacek, Jiri


    Obsessive-compulsive disorder (OCD) is a neuropsychiatric disorder with 1-3% prevalence. OCD is characterized by recurrent thoughts (obsessions) and repetitive behaviors (compulsions). The pathophysiology of OCD remains unclear, stressing the importance of pre-clinical studies. The aim of this article is to critically review a proposed animal model of OCD that is characterized by the induction of compulsive checking and behavioral sensitization to the D2/D3 dopamine agonist quinpirole. Changes in this model have been reported at the level of brain structures, neurotransmitter systems and other neurophysiological aspects. In this review, we consider these alterations in relation to the clinical manifestations in OCD, with the aim to discuss and evaluate axes of validity of this model. Our analysis shows that some axes of validity of quinpirole sensitization model (QSM) are strongly supported by clinical findings, such as behavioral phenomenology or roles of brain structures. Evidence on predictive validity is contradictory and ambiguous. It is concluded that this model is useful in the context of searching for the underlying pathophysiological basis of the disorder because of the relatively strong biological similarities with OCD.

  11. Cumulative risks of foster care placement for Danish children. (United States)

    Fallesen, Peter; Emanuel, Natalia; Wildeman, Christopher


    Although recent research suggests that the cumulative risk of foster care placement is far higher for American children than originally suspected, little is known about the cumulative risk of foster care placement in other countries, which makes it difficult to gauge the degree to which factor foster care placement is salient in other contexts. In this article, we provide companion estimates to those provided in recent work on the US by using Danish registry data and synthetic cohort life tables to show how high and unequally distributed the cumulative risk of foster care placement is for Danish children. Results suggest that at the beginning of the study period (in 1998) the cumulative risk of foster care placement for Danish children was roughly in line with the risk for American children. Yet, by the end of the study period (2010), the risk had declined to half the risk for American children. Our results also show some variations by parental ethnicity and sex, but these differences are small. Indeed, they appear quite muted relative to racial/ethnic differences in these risks in the United States. Last, though cumulative risks are similar between Danish and American children (especially at the beginning of the study period), the age-specific risk profiles are markedly different, with higher risks for older Danish children than for older American children.


    Energy Technology Data Exchange (ETDEWEB)

    Behroozi, Peter S.; Wechsler, Risa H. [Kavli Institute for Particle Astrophysics and Cosmology, SLAC National Accelerator Laboratory, Stanford, CA 94305 (United States); Marchesini, Danilo [Department of Physics and Astronomy, Tufts University, Medford, MA 02155 (United States); Muzzin, Adam [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands); Papovich, Casey [Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States); Stefanon, Mauro [Physics and Astronomy Department, University of Missouri, Columbia, MO 65211 (United States)


    Comparing galaxies across redshifts at fixed cumulative number density is a popular way to estimate the evolution of specific galaxy populations. This method ignores scatter in mass accretion histories and galaxy-galaxy mergers, which can lead to errors when comparing galaxies over large redshift ranges (Δz > 1). We use abundance matching in the ΛCDM paradigm to estimate the median change in cumulative number density with redshift and provide a simple fit (+0.16 dex per unit Δz) for progenitors of z = 0 galaxies. We find that galaxy descendants do not evolve in the same way as galaxy progenitors, largely due to scatter in mass accretion histories. We also provide estimates for the 1σ range of cumulative number densities corresponding to galaxy progenitors and descendants. Finally, we discuss some limits on cumulative number density comparisons, which arise due to difficulties measuring physical quantities (e.g., stellar mass) consistently across redshifts. A public tool to calculate cumulative number density evolution for galaxies, as well as approximate halo masses, is available online.

  13. Maintenance hemodialysis patients have high cumulative radiation exposure.

    LENUS (Irish Health Repository)

    Kinsella, Sinead M


    Hemodialysis is associated with an increased risk of neoplasms which may result, at least in part, from exposure to ionizing radiation associated with frequent radiographic procedures. In order to estimate the average radiation exposure of those on hemodialysis, we conducted a retrospective study of 100 patients in a university-based dialysis unit followed for a median of 3.4 years. The number and type of radiological procedures were obtained from a central radiology database, and the cumulative effective radiation dose was calculated using standardized, procedure-specific radiation levels. The median annual radiation dose was 6.9 millisieverts (mSv) per patient-year. However, 14 patients had an annual cumulative effective radiation dose over 20 mSv, the upper averaged annual limit for occupational exposure. The median total cumulative effective radiation dose per patient over the study period was 21.7 mSv, in which 13 patients had a total cumulative effective radiation dose over 75 mSv, a value reported to be associated with a 7% increased risk of cancer-related mortality. Two-thirds of the total cumulative effective radiation dose was due to CT scanning. The average radiation exposure was significantly associated with the cause of end-stage renal disease, history of ischemic heart disease, transplant waitlist status, number of in-patient hospital days over follow-up, and death during the study period. These results highlight the substantial exposure to ionizing radiation in hemodialysis patients.

  14. A fractal model for nuclear organization: current evidence and biological implications (United States)

    Bancaud, Aurélien; Lavelle, Christophe; Huet, Sébastien; Ellenberg, Jan


    Chromatin is a multiscale structure on which transcription, replication, recombination and repair of the genome occur. To fully understand any of these processes at the molecular level under physiological conditions, a clear picture of the polymorphic and dynamic organization of chromatin in the eukaryotic nucleus is required. Recent studies indicate that a fractal model of chromatin architecture is consistent with both the reaction-diffusion properties of chromatin interacting proteins and with structural data on chromatin interminglement. In this study, we provide a critical overview of the experimental evidence that support a fractal organization of chromatin. On this basis, we discuss the functional implications of a fractal chromatin model for biological processes and propose future experiments to probe chromatin organization further that should allow to strongly support or invalidate the fractal hypothesis. PMID:22790985

  15. Growth and renewable energy in Europe: A random effect model with evidence for neutrality hypothesis

    International Nuclear Information System (INIS)

    Menegaki, Angeliki N.


    This is an empirical study on the causal relationship between economic growth and renewable energy for 27 European countries in a multivariate panel framework over the period 1997-2007 using a random effect model and including final energy consumption, greenhouse gas emissions and employment as additional independent variables in the model. Empirical results do not confirm causality between renewable energy consumption and GDP, although panel causality tests unfold short-run relationships between renewable energy and greenhouse gas emissions and employment. The estimated cointegration factor refrains from unity, indicating only a weak, if any, relationship between economic growth and renewable energy consumption in Europe, suggesting evidence of the neutrality hypothesis, which can partly be explained by the uneven and insufficient exploitation of renewable energy sources across Europe.

  16. Symmetry breaking and adaptation: evidence from a 'toy model' of a virus. (United States)

    Vargas, J M; Stephens, C R; Waelbroeck, H; Zertuche, F


    We argue that an induced breaking of the genetic synonym symmetry due to the action of genetic operators such as mutation can enhance the adaptability of a species to changes in the environment. In the case of a virus, the claim is that the codon bias in the neutralization epitope improves the virus' ability to generate mutants that evade the induced immune response. We support our claim with a simple 'toy model' of a viral epitope evolving in competition with the immune system. The effective selective advantage of a higher mutability leads to a dominance of codons that favor non-synonymous mutations. As further evidence we present a simple model for a genetic regulatory network that leads to adaptive evolution in a population of giraffes by means of an induced symmetry breaking rather than through any direct selective advantage.

  17. Predicting the adoption of evidence-based practice using "Rogers diffusion of innovation model". (United States)

    Pashaeypoor, Shahzad; Ashktorab, Tahereh; Rassouli, Maryam; Alavi-Majd, Hamid


    Predicting the significant determinants of adopting evidence-based practice (EBP) by nursing students has received little attention in the nursing education literature. The purpose of this study was to investigate the predictors of EBP adoption among Iranian nursing students and to evaluate the fitness of the research model derived from Rogers' model. The study was a cross-sectional survey of 170 nursing students. A path analysis was conducted to predict the determinants of EBP in nursing students. Also, direct and indirect effects of the variables were calculated. The results indicated that knowledge of EBP as well as its perceived complexity, observability and trialability significantly predicted the adoption of EBP. Among the variables, knowledge of EBP had the greatest total impact on the adoption of EBP (P adoption of EBP. The results of this study can be used by health professionals such as nursing managers and educators for teaching any new concept in clinical and educational settings such as EBP.

  18. A critical examination of the youth foyer model for alleviating homelessness: Strengthening a promising evidence base

    Directory of Open Access Journals (Sweden)

    Iris Levin


    Full Text Available This article assesses the quality of 15 primary studies that examined the effectiveness of youth foyer or foyer-like programs on the lives of young homeless people. The youth foyer model provides an integrated approach to tackling youth homelessness, connecting affordable accommodation to training and employment. In Australia, there is growing support from government for the development and funding of foyer programs. However to date, there has been very limited development and investment in the evidence base on the effectiveness of this model in Australia or internationally. Following an extensive literature search, we argue that there is a need to lift the standard of the evidence base of youth foyer effectiveness. We discuss two main issues: the difficulty studies had validating claims of foyer effectiveness, and limitations of research design and methodology. The implications of the lack of rigour in the research reviewed are three-fold. Firstly, youth foyer evaluation study quality could be improved by: clearer methodological and model documentation; post intervention follow-up design; comparison of data to non-randomised comparison groups; and a pre-publication peer-review process. This would be supported with clearer expectations from the research community regarding the production and assessment of grey literature. Secondly, while the standard of reporting needs to be raised, the ‘gold standard’ (i.e. randomised controlled trials of research design in the scientific community is not a relevant benchmark in the field of homelessness research. This is due to the complexity of homelessness interventions and the inadequate funding of the homelessness research field. Greater investment in robust research and evaluation should accompany the substantial investment in youth foyer programs in order to accurately appraise the effectiveness of the youth foyer model. Thirdly, the lack of rigour in the studies reviewed suggests gaps in the service

  19. Low Level Evidence Suggests That Librarian-Led Instruction in Evidence Based Practice is Effective Regardless of Instructional Model

    Directory of Open Access Journals (Sweden)

    Lindsay J. Alcock


    Full Text Available A Review of: Swanberg, S. M., Dennison, C. C., Farrell, A., Machel, V., Marton, C., O'Brien, K. K., … & Holyoke, A. N. (2016. Instructional methods used by health sciences librarians to teach evidence-based practice (EBP: a systematic review. Journal of the Medical Library Association: JMLA, 104(3, 197-208. Abstract Objective – To determine both the instructional methods and their effectiveness in teaching evidence based practice (EBP by librarians in health sciences curricula. Design – Systematic review. Setting – A total of 16 databases, Google Scholar, and MLA Annual Meeting abstracts. Subjects – There were 27 studies identified through a systematic literature search. Methods – An exhaustive list of potential articles was gathered through searching 16 online databases, Google Scholar, and MLA Annual Conference abstracts. Inclusion and exclusion criteria were identified to inform the literature search and determine article eligibility. Duplicates were removed and the remaining search results were divided into sets and assigned to two reviewers who screened first by title/abstract and then by full-text. A third reviewer addressed disagreement in article inclusion. Data extraction, using a validated method described by Koufogiannakis and Wiebe (2006, and critical appraisal, using the Glasgow checklist (1999, were performed concurrently. Main Results – After removal of duplicates 30,043 articles were identified for initial title/abstract screening. Of the 637 articles assessed for full-text screening 26 articles and 1 conference proceeding ultimately met all eligibility criteria. There was no meta-analysis included in the synthesis. There were 16 articles published in library and information science journals and 10 in health sciences journals. Of those studies, 22 were conducted in the United States. A wide range of user groups was identified as participants in the studies with medical

  20. Tests of linear and nonlinear relations between cumulative contextual risk at birth and psychosocial problems during adolescence. (United States)

    Parra, Gilbert R; Smith, Gail L; Mason, W Alex; Savolainen, Jukka; Chmelka, Mary B; Miettunen, Jouko; Järvelin, Marjo-Riitta


    This study tested whether there are linear or nonlinear relations between prenatal/birth cumulative risk and psychosocial outcomes during adolescence. Participants (n = 6963) were taken from the Northern Finland Birth Cohort Study 1986. The majority of participants did not experience any contextual risk factors around the time of the target child's birth (58.1%). Even in this low-risk sample, cumulative contextual risk assessed around the time of birth was related to seven different psychosocial outcomes 16 years later. There was some evidence for nonlinear effects, but only for substance-related outcomes; however, the form of the association depended on how the cumulative risk index was calculated. Gender did not moderate the relation between cumulative risk and any of the adolescent psychosocial outcomes. Results highlight the potential value of using the cumulative risk framework for identifying children at birth who are at risk for a range of poor psychosocial outcomes during adolescence. Copyright © 2017 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  1. Evidence Evaluation: Measure "Z" Corresponds to Human Utility Judgments Better than Measure "L" and Optimal-Experimental-Design Models (United States)

    Rusconi, Patrice; Marelli, Marco; D'Addario, Marco; Russo, Selena; Cherubini, Paolo


    Evidence evaluation is a crucial process in many human activities, spanning from medical diagnosis to impression formation. The present experiments investigated which, if any, normative model best conforms to people's intuition about the value of the obtained evidence. Psychologists, epistemologists, and philosophers of science have proposed…

  2. Numerical evidence of liquid crystalline mesophases of a lollipop shaped model in two dimensions (United States)

    Pérez-Lemus, G. R.; Armas-Pérez, J. C.; Chapela, G. A.; Quintana-H., J.


    Small alterations in the molecular details may produce noticeable changes in the symmetry of the resulting phase behavior. It is possible to produce morphologies having different n-fold symmetries by manipulating molecular features such as chirality, polarity or anisotropy. In this paper, a two dimensional hard molecular model is introduced to study the formation of liquid crystalline phases in low dimensionality. The model is similar to that reported by Julio C. Armas-Pérez and Jacqueline Quintana-H., Phys. Rev. E 83, 051709 (2011). The main difference is the lack of chirality in the model proposed, although they share some characteristics like the geometrical polarity. Our model is called a lollipop model, because its shape is constructed by a rounded section attached to the end of a stick. Contrary to what happens in three dimensions where chiral nematogens produce interesting and complex phases such as blue phases, the lack of molecular chirality of our model generates a richer phase diagram compared to the chiral system. We show numerical and some geometrical evidences that the lack of laterality of the non chiral model seems to provide more routes of molecular self-assembly, producing triatic, a random cluster and possibly a tetratic phase behavior which were not presented in the previous work. We support our conclusions using results obtained from isobaric and isochoric Monte Carlo simulations. Properties as the n-fold order parameters such as the nematic, tetratic and triatic as well as their correlation functions were used to characterize the phases. We also provide the Fourier transform of equilibrium configurations to analyze the n-fold symmetry characteristic of each phase.

  3. Improved evidence-based genome-scale metabolic models for maize leaf, embryo, and endosperm

    Energy Technology Data Exchange (ETDEWEB)

    Seaver, Samuel M. D.; Bradbury, Louis M. T.; Frelin, Océane; Zarecki, Raphy; Ruppin, Eytan; Hanson, Andrew D.; Henry, Christopher S.


    There is a growing demand for genome-scale metabolic reconstructions for plants, fueled by the need to understand the metabolic basis of crop yield and by progress in genome and transcriptome sequencing. Methods are also required to enable the interpretation of plant transcriptome data to study how cellular metabolic activity varies under different growth conditions or even within different organs, tissues, and developmental stages. Such methods depend extensively on the accuracy with which genes have been mapped to the biochemical reactions in the plant metabolic pathways. Errors in these mappings lead to metabolic reconstructions with an inflated number of reactions and possible generation of unreliable metabolic phenotype predictions. Here we introduce a new evidence-based genome-scale metabolic reconstruction of maize, with significant improvements in the quality of the gene-reaction associations included within our model. We also present a new approach for applying our model to predict active metabolic genes based on transcriptome data. This method includes a minimal set of reactions associated with low expression genes to enable activity of a maximum number of reactions associated with high expression genes. We apply this method to construct an organ-specific model for the maize leaf, and tissue specific models for maize embryo and endosperm cells. We validate our models using fluxomics data for the endosperm and embryo, demonstrating an improved capacity of our models to fit the available fluxomics data. All models are publicly available via the DOE Systems Biology Knowledgebase and PlantSEED, and our new method is generally applicable for analysis transcript profiles from any plant, paving the way for further in silico studies with a wide variety of plant genomes.

  4. Wick polynomials and time-evolution of cumulants (United States)

    Lukkarinen, Jani; Marcozzi, Matteo


    We show how Wick polynomials of random variables can be defined combinatorially as the unique choice, which removes all "internal contractions" from the related cumulant expansions, also in a non-Gaussian case. We discuss how an expansion in terms of the Wick polynomials can be used for derivation of a hierarchy of equations for the time-evolution of cumulants. These methods are then applied to simplify the formal derivation of the Boltzmann-Peierls equation in the kinetic scaling limit of the discrete nonlinear Schödinger equation (DNLS) with suitable random initial data. We also present a reformulation of the standard perturbation expansion using cumulants, which could simplify the problem of a rigorous derivation of the Boltzmann-Peierls equation by separating the analysis of the solutions to the Boltzmann-Peierls equation from the analysis of the corrections. This latter scheme is general and not tied to the DNLS evolution equations.

  5. Baltic Sea biodiversity status vs. cumulative human pressures

    DEFF Research Database (Denmark)

    Andersen, Jesper H.; Halpern, Benjamin S.; Korpinen, Samuli


    Abstract Many studies have tried to explain spatial and temporal variations in biodiversity status of marine areas from a single-issue perspective, such as fishing pressure or coastal pollution, yet most continental seas experience a wide range of human pressures. Cumulative impact assessments have...... been developed to capture the consequences of multiple stressors for biodiversity, but the ability of these assessments to accurately predict biodiversity status has never been tested or ground-truthed. This relationship has similarly been assumed for the Baltic Sea, especially in areas with impaired...... status, but has also never been documented. Here we provide a first tentative indication that cumulative human impacts relate to ecosystem condition, i.e. biodiversity status, in the Baltic Sea. Thus, cumulative impact assessments offer a promising tool for informed marine spatial planning, designation...

  6. Solid-state electro-cumulation effect numerical simulation

    CERN Document Server

    Grishin, V G


    It is an attempt to simulate as really as possible a crystal's interatomic interaction under conditions of "Solid-state electro-cumulation (super-polarization) effect". Some theoretical and experimental reasons to believe that within solid substances an interparticles interaction could concentrate from the surface to a centre were given formerly. Now, numerical results show the conditions that could make the cumulation more effective. Another keywords: ion, current, solid, symmetry, cumulation, polarization, depolarization, ionic conductor,superionic conductor, ice, crystal, strain, V-center, V-centre, doped crystal, interstitial impurity, intrinsic color center, high pressure technology, Bridgman, anvil, experiment, crowdion, dielectric, proton, layer, defect, lattice, dynamics, electromigration, mobility, muon catalysis, concentration, doping, dopant, conductivity, pycnonuclear reaction, permittivity, dielectric constant, point defects, interstitials, polarizability, imperfection, defect centers, glass, epi...

  7. Learning curve for fetoscopic laser surgery using cumulative sum analysis. (United States)

    Peeters, Suzanne H P; Van Zwet, Erik W; Oepkes, Dick; Lopriore, Enrico; Klumper, Frans J; Middeldorp, Johanna M


    To identify a learning curve and monitor operator performance for fetoscopic laser surgery for twin-to-twin transfusion syndrome using cumulative sum analysis. Retrospective cohort study. National tertiary referral center for invasive fetal therapy. A total of 340 consecutive monochorionic pregnancies with twin-to-twin transfusion syndrome treated with fetoscopic laser coagulation between August 2000 and December 2010. A learning curve was generated using learning curve cumulative sum analysis and cumulative sum methodology to assess changes in double survival across the case sequence. Laser surgery was initially performed by two operators, joined by a third and fourth operator after 1 and 2 years, respectively. Individual operator performance, double perinatal survival at 4 weeks. Overall survival of both twins occurred in 59% (201/340), median gestational age at birth was 32.0 weeks. Cumulative sum graphs showed that level of competence for double survival for the operators was reached after 26, 25, 26, and 35 procedures, respectively. Two operators kept their competence level and continued to improve after completing the initial learning process; two others went out of control at one point in time, according to the cumulative sum boundaries. A difference in learning effect was associated with number of procedures performed annually and previous experience with other ultrasound-guided invasive procedures. This study shows that all operators reached a level of competence after at least 25 fetoscopic laser procedures and confirms the value of using the cumulative sum method both for learning curve assessment and for ongoing quality control. © 2014 Nordic Federation of Societies of Obstetrics and Gynecology.

  8. Cumulative carbon as a policy framework for achieving climate stabilization (United States)

    Matthews, H. Damon; Solomon, Susan; Pierrehumbert, Raymond


    The primary objective of the United Nations Framework Convention on Climate Change is to stabilize greenhouse gas concentrations at a level that will avoid dangerous climate impacts. However, greenhouse gas concentration stabilization is an awkward framework within which to assess dangerous climate change on account of the significant lag between a given concentration level and the eventual equilibrium temperature change. By contrast, recent research has shown that global temperature change can be well described by a given cumulative carbon emissions budget. Here, we propose that cumulative carbon emissions represent an alternative framework that is applicable both as a tool for climate mitigation as well as for the assessment of potential climate impacts. We show first that both atmospheric CO2 concentration at a given year and the associated temperature change are generally associated with a unique cumulative carbon emissions budget that is largely independent of the emissions scenario. The rate of global temperature change can therefore be related to first order to the rate of increase of cumulative carbon emissions. However, transient warming over the next century will also be strongly affected by emissions of shorter lived forcing agents such as aerosols and methane. Non-CO2 emissions therefore contribute to uncertainty in the cumulative carbon budget associated with near-term temperature targets, and may suggest the need for a mitigation approach that considers separately short- and long-lived gas emissions. By contrast, long-term temperature change remains primarily associated with total cumulative carbon emissions owing to the much longer atmospheric residence time of CO2 relative to other major climate forcing agents. PMID:22869803

  9. Self-esteem Is Mostly Stable Across Young Adulthood: Evidence from Latent STARTS Models. (United States)

    Wagner, Jenny; Lüdtke, Oliver; Trautwein, Ulrich


    How stable is self-esteem? This long-standing debate has led to different conclusions across different areas of psychology. Longitudinal data and up-to-date statistical models have recently indicated that self-esteem has stable and autoregressive trait-like components and state-like components. We applied latent STARTS models with the goal of replicating previous findings in a longitudinal sample of young adults (N = 4,532; Mage  = 19.60, SD = 0.85; 55% female). In addition, we applied multigroup models to extend previous findings on different patterns of stability for men versus women and for people with high versus low levels of depressive symptoms. We found evidence for the general pattern of a major proportion of stable and autoregressive trait variance and a smaller yet substantial amount of state variance in self-esteem across 10 years. Furthermore, multigroup models suggested substantial differences in the variance components: Females showed more state variability than males. Individuals with higher levels of depressive symptoms showed more state and less autoregressive trait variance in self-esteem. Results are discussed with respect to the ongoing trait-state debate and possible implications of the group differences that we found in the stability of self-esteem. © 2015 Wiley Periodicals, Inc.

  10. Evaluating resveratrol as a therapeutic bone agent: preclinical evidence from rat models of osteoporosis. (United States)

    Tou, Janet C


    Resveratrol (RSV) is a naturally occurring plant polyphenol that has potential to attenuate osteoporosis with distinct pathologies. This review evaluates preclinical evidence regarding the efficacy and safety of RSV as a therapeutic bone agent using different rat models. Limitations of these animal models are discussed, and suggestions for strengthening the experimental design of future studies are provided. The ovariectomized rat model of postmenopausal osteoporosis reported that RSV supplementation attenuated estrogen deficiency-induced bone loss and trabecular structural deterioration. RSV safety was indicated by the absence of stimulation of estrogen-sensitive tissue. Providing RSV to rats aged >6 months attenuated age-related bone mass loss and structural deterioration but produced inconsistent effects on bones in rats aged osteoporosis reported that RSV attenuated bone loss in old rats, but higher doses and longer duration supplementation before mechanical loading were required for younger rats. Limitations common to studies using rat models of osteoporosis include requirements to include animals that are skeletally mature, longer study durations, and to adjust for potential confounding effects due to altered body weight and endocrine function. Strengthening experimental design can contribute to translation of animal results to clinically relevant recommendations for humans. Published 2015. This article is U.S. Government work and is in the public domain in the USA.

  11. A review of the evidence linking adult attachment theory and chronic pain: presenting a conceptual model. (United States)

    Meredith, Pamela; Ownsworth, Tamara; Strong, Jenny


    It is now well established that pain is a multidimensional phenomenon, affected by a gamut of psychosocial and biological variables. According to diathesis-stress models of chronic pain, some individuals are more vulnerable to developing disability following acute pain because they possess particular psychosocial vulnerabilities which interact with physical pathology to impact negatively upon outcome. Attachment theory, a theory of social and personality development, has been proposed as a comprehensive developmental model of pain, implicating individual adult attachment pattern in the ontogenesis and maintenance of chronic pain. The present paper reviews and critically appraises studies which link adult attachment theory with chronic pain. Together, these papers offer support for the role of insecure attachment as a diathesis (or vulnerability) for problematic adjustment to pain. The Attachment-Diathesis Model of Chronic Pain developed from this body of literature, combines adult attachment theory with the diathesis-stress approach to chronic pain. The evidence presented in this review, and the associated model, advances our understanding of the developmental origins of chronic pain conditions, with potential application in guiding early pain intervention and prevention efforts, as well as tailoring interventions to suit specific patient needs.

  12. A study of cumulative fatigue damage in AISI 4130 steel (United States)

    Jeelani, S.; Musial, M.


    Experimental data were obtained using AISI 4130 steel under stress ratios of -1 and 0. A study of cumulative fatigue damage using Miner's and Kramer's equations for stress ratios of -1 and 0 for low-high, low-high-mixed, high-low, and high-low-mixed stress sequences has revealed that there is a close agreement between the theoretical and experimental values of fatigue damage and fatigue life. Kramer's equation predicts less conservative and more realistic cumulative fatigue damage than the popularly used Miner's rule does.

  13. The role of factorial cumulants in reactor neutron noise theory

    International Nuclear Information System (INIS)

    Colombino, A.; Pacilio, N.; Sena, G.


    The physical meaning and the combinatorial implications of the factorial cumulant of a state variable such as the number of neutrons or the number of neutron counts are specified. Features of the presentation are: (1) the fission process is treated in its entirety without the customary binary emission restriction, (b) the introduction of the factorial cumulants helps in reducing the complexity of the mathematical problems, (c) all the solutions can be obtained analytically. Only the ergodic hypothesis for the neutron population evolution is dealt with. (author)

  14. Cumulative Incidence of Cancer After Solid Organ Transplantation (United States)

    Hall, Erin C.; Pfeiffer, Ruth M.; Segev, Dorry L.; Engels, Eric A.


    BACKGROUND Solid organ transplantation recipients have elevated cancer incidence. Estimates of absolute cancer risk after transplantation can inform prevention and screening. METHODS The Transplant Cancer Match Study links the US transplantation registry with 14 state/regional cancer registries. The authors used nonparametric competing risk methods to estimate the cumulative incidence of cancer after transplantation for 2 periods (1987–1999 and 2000–2008). For recipients from 2000 to 2008, the 5-year cumulative incidence, stratified by organ, sex, and age at transplantation, was estimated for 6 preventable or screen-detectable cancers. For comparison, the 5-year cumulative incidence was calculated for the same cancers in the general population at representative ages using Surveillance, Epidemiology, and End Results data. RESULTS Among 164,156 recipients, 8520 incident cancers were identified. The absolute cancer risk was slightly higher for recipients during the period from 2000 to 2008 than during the period from 1987 to 1999 (5-year cumulative incidence: 4.4% vs 4.2%; P =.006); this difference arose from the decreasing risk of competing events (5-year cumulative incidence of death, graft failure, or retransplantation: 26.6% vs 31.9%; P 50 years; range, 0.36%–2.22%). For recipients aged >50 years, the 5-year cumulative incidence was higher for colorectal cancer (range, 0.33%–1.94%) than for the general population at the recommended screening age (aged 50 years: range, 0.25%–0.33%). For recipients aged >50 years, the 5-year cumulative incidence was high for lung cancer among thoracic organ recipients (range, 1.16%–3.87%) and for kidney cancer among kidney recipients (range, 0.53%–0.84%). The 5-year cumulative incidence for prostate cancer and breast cancer was similar or lower in transplantation recipients than at the recommended ages of screening in the general population. CONCLUSIONS Subgroups of transplantation recipients have a high absolute risk

  15. Integrating environmental monitoring with cumulative effects management and decision making. (United States)

    Cronmiller, Joshua G; Noble, Bram F


    Cumulative effects (CE) monitoring is foundational to emerging regional and watershed CE management frameworks, yet monitoring is often poorly integrated with CE management and decision-making processes. The challenges are largely institutional and organizational, more so than scientific or technical. Calls for improved integration of monitoring with CE management and decision making are not new, but there has been limited research on how best to integrate environmental monitoring programs to ensure credible CE science and to deliver results that respond to the more immediate questions and needs of regulatory decision makers. This paper examines options for the integration of environmental monitoring with CE frameworks. Based on semistructured interviews with practitioners, regulators, and other experts in the Lower Athabasca, Alberta, Canada, 3 approaches to monitoring system design are presented. First, a distributed monitoring system, reflecting the current approach in the Lower Athabasca, where monitoring is delegated to different external programs and organizations; second, a 1-window system in which monitoring is undertaken by a single, in-house agency for the purpose of informing management and regulatory decision making; third, an independent system driven primarily by CE science and understanding causal relationships, with knowledge adopted for decision support where relevant to specific management questions. The strengths and limitations of each approach are presented. A hybrid approach may be optimal-an independent, nongovernment, 1-window model for CE science, monitoring, and information delivery-capitalizing on the strengths of distributed, 1-window, and independent monitoring systems while mitigating their weaknesses. If governments are committed to solving CE problems, they must invest in the long-term science needed to do so; at the same time, if science-based monitoring programs are to be sustainable over the long term, they must be responsive to

  16. Cumulative Effects of Barriers on the Movements of Forest Birds

    Directory of Open Access Journals (Sweden)

    Marc Bélisle


    Full Text Available Although there is a consensus of opinion that habitat fragmentation has deleterious effects on animal populations, primarily by inhibiting dispersal among remaining patches, there have been few explicit demonstrations of the ways by which degraded habitats actually constrain individual movement. Two impediments are primarily responsible for this paucity: it is difficult to separate the effects of habitat fragmentation (configuration from habitat loss (composition, and conventional measures of fragmented habitats are assumed to be, but probably are not, isotropic. We addressed these limitations by standardizing differences in forest cover in a clearly anisotropic configuration of habitat fragmentation by conducting a homing experiment with three species of forest birds in the Bow Valley of Banff National Park, Canada. Birds were translocated (1.2-3.5  km either parallel or perpendicular to four/five parallel barriers that are assumed to impede the cross-valley travel of forest-dependent animals. Taken together, individuals exhibited longer return times when they were translocated across these barriers, but differences among species suggest a more complex interpretation. A long-distance migrant (Yellow-rumped Warbler, Dendroica coronata behaved as predicted, but a short-distance migrant (Golden-crowned Kinglet, Regulus satrapa was indifferent to barrier configuration. A resident (Red-breasted Nuthatch, Sitta canadensis exhibited longer return times when it was translocated parallel to the barriers. Our results suggest that an anisotropic arrangement of small, open areas in fragmented landscapes can have a cumulative barrier effect on the movement of forest animals, but that both modelers and managers will have to acknowledge potentially counterintuitive differences among species to predict the effect that these may have on individual movement and, ultimately, dispersal.

  17. Cumulative effects of fecal contamination from combined sewer overflows: Management for source water protection. (United States)

    Jalliffier-Verne, Isabelle; Heniche, Mourad; Madoux-Humery, Anne-Sophie; Galarneau, Martine; Servais, Pierre; Prévost, Michèle; Dorner, Sarah


    The quality of a drinking water source depends largely on upstream contaminant discharges. Sewer overflows can have a large influence on downstream drinking water intakes as they discharge untreated or partially treated wastewaters that may be contaminated with pathogens. This study focuses on the quantification of Escherichia coli discharges from combined sewer overflows (CSOs) and the dispersion and diffusion in receiving waters in order to prioritize actions for source water protection. E. coli concentrations from CSOs were estimated from monitoring data at a series of overflow structures and then applied to the 42 active overflow structures between 2009 and 2012 using a simple relationship based upon the population within the drainage network. From these estimates, a transport-dispersion model was calibrated with data from a monitoring program from both overflow structures and downstream drinking water intakes. The model was validated with 15 extreme events such as a large number of overflows (n > 8) or high concentrations at drinking water intakes. Model results demonstrated the importance of the cumulative effects of CSOs on the degradation of water quality downstream. However, permits are typically issued on a discharge point basis and do not consider cumulative effects. Source water protection plans must consider the cumulative effects of discharges and their concentrations because the simultaneous discharge of multiple overflows can lead to elevated E. coli concentrations at a drinking water intake. In addition, some CSOs have a disproportionate impact on peak concentrations at drinking water intakes. As such, it is recommended that the management of CSOs move away from frequency based permitting at the discharge point to focus on the development of comprehensive strategies to reduce cumulative and peak discharges from CSOs upstream of drinking water intakes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. A sampling-based computational strategy for the representation of epistemic uncertainty in model predictions with evidence theory.

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, J. D. (Prostat, Mesa, AZ); Oberkampf, William Louis; Helton, Jon Craig (Arizona State University, Tempe, AZ); Storlie, Curtis B. (North Carolina State University, Raleigh, NC)


    Evidence theory provides an alternative to probability theory for the representation of epistemic uncertainty in model predictions that derives from epistemic uncertainty in model inputs, where the descriptor epistemic is used to indicate uncertainty that derives from a lack of knowledge with respect to the appropriate values to use for various inputs to the model. The potential benefit, and hence appeal, of evidence theory is that it allows a less restrictive specification of uncertainty than is possible within the axiomatic structure on which probability theory is based. Unfortunately, the propagation of an evidence theory representation for uncertainty through a model is more computationally demanding than the propagation of a probabilistic representation for uncertainty, with this difficulty constituting a serious obstacle to the use of evidence theory in the representation of uncertainty in predictions obtained from computationally intensive models. This presentation describes and illustrates a sampling-based computational strategy for the representation of epistemic uncertainty in model predictions with evidence theory. Preliminary trials indicate that the presented strategy can be used to propagate uncertainty representations based on evidence theory in analysis situations where naive sampling-based (i.e., unsophisticated Monte Carlo) procedures are impracticable due to computational cost.

  19. Implementing three evidence-based program models: early lessons from the Teen Pregnancy Prevention Replication Study. (United States)

    Kelsey, Meredith; Layzer, Jean


    This article describes some of the early implementation challenges faced by nine grantees participating in the Teen Pregnancy Prevention Replication Study and their response to them. The article draws on information collected as part of a comprehensive implementation study. Sources include site and program documents; program officer reports; notes from site investigation, selection and negotiation; ongoing communications with grantees as part of putting the study into place; and semi-structured interviews with program staff. The issues faced by grantees in implementing evidence-based programs designed to prevent teen pregnancy varied by program model. Grantees implementing a classroom-based curriculum faced challenges in delivering the curriculum within the constraints of school schedules and calendars (program length and size of class). Grantees implementing a culturally tailored curriculum faced a series of challenges, including implementing the intervention as part of the regular school curriculum in schools with diverse populations; low attendance when delivered as an after-school program; and resistance on the part of schools to specific curriculum content. The third set of grantees, implementing a program in clinics, faced challenges in identifying and recruiting young women into the program and in retaining young women once they were in the program. The experiences of these grantees reflect some of the complexities that should be carefully considered when choosing to replicate evidence-based programs. The Teen Pregnancy Prevention replication study will provide important context for assessing the effectiveness of some of the more widely replicated evidence-based programs. Copyright © 2014 Society for Adolescent Health and Medicine. All rights reserved.

  20. Modeling mountain pine beetle disturbance in Glacier National Park using multiple lines of evidence (United States)

    Assal, Timothy; Sibold, Jason


    Temperate forest ecosystems are subject to various disturbances which contribute to ecological legacies that can have profound effects on the structure of the ecosystem. Impacts of disturbance can vary widely in extent, duration and severity over space and time. Given that global climate change is expected to increase rates of forest disturbance, an understanding of these events are critical in the interpretation of contemporary forest patterns and those of the near future. We seek to understand the impact of the 1970s mountain pine beetle outbreak on the landscape of Glacier National Park and investigate any connection between this event and subsequent decades of extensive wildfire. The lack of spatially explicit data on the mountain pine beetle disturbance represents a major data gap and inhibits our ability to test for correlations between outbreak severity and fire severity. To overcome this challenge, we utilized multiple lines of evidence to model forest canopy mortality as a proxy for outbreak severity. We used historical aerial and landscape photos, reports, aerial survey data, a six year collection of Landsat imagery and abiotic data in combination with regression analysis. The use of remotely sensed data is critical in large areas where subsequent disturbance (fire) has erased some of the evidence from the landscape. Results indicate that this method is successful in capturing the spatial heterogeneity of the outbreak in a topographically complex landscape. Furthermore, this study provides an example on the use of existing data to reduce levels of uncertainty associated with an historic disturbance.

  1. Expertise in evidence-based medicine: a tale of three models. (United States)

    Wieten, Sarah


    Expertise has been a contentious concept in Evidence-Based Medicine (EBM). Especially in the early days of the movement, expertise was taken to be exactly what EBM was rebelling against-the authoritarian pronouncements about "best" interventions dutifully learned in medical schools, sometimes with dire consequences. Since then, some proponents of EBM have tried various ways of reincorporating the idea of expertise into EBM, with mixed results. However, questions remain. Is expertise evidence? If not, what is it good for, if anything? In this article, I describe and analyze the three historical models of expertise integration in EBM and discuss the difficulties in putting each into practice. I also examine accounts of expertise from disciplines outside of medicine, including philosophy, sociology, psychology, and science and technology studies to see if these accounts can strengthen and clarify what EBM has to say about expertise. Of the accounts of expertise discussed here, the Collins and Evans account can do most to clarify the concept of expertise in EBM. With some additional clarification from EBM proper, theoretical resources from other disciplines might augment the current EBM account of expertise.

  2. Evidence for the Magnetic Breakout Model in an Equatorial Coronal-hole Jet (United States)

    Kumar, Pankaj; Karpen, Judith T.; Antiochos, Spiro K.; Wyper, Peter F.; DeVore, C. Richard; DeForest, Craig E.


    Small, impulsive jets commonly occur throughout the solar corona, but are especially visible in coronal holes. Evidence is mounting that jets are part of a continuum of eruptions that extends to much larger coronal mass ejections and eruptive flares. Because coronal-hole jets originate in relatively simple magnetic structures, they offer an ideal testbed for theories of energy buildup and release in the full range of solar eruptions. We analyzed an equatorial coronal-hole jet observed by the Solar Dynamics Observatory (SDO)/AIA on 2014 January 9 in which the magnetic-field structure was consistent with the embedded-bipole topology that we identified and modeled previously as an origin of coronal jets. In addition, this event contained a mini-filament, which led to important insights into the energy storage and release mechanisms. SDO/HMI magnetograms revealed footpoint motions in the primary minority-polarity region at the eruption site, but show negligible flux emergence or cancellation for at least 16 hr before the eruption. Therefore, the free energy powering this jet probably came from magnetic shear concentrated at the polarity inversion line within the embedded bipole. We find that the observed activity sequence and its interpretation closely match the predictions of the breakout jet model, strongly supporting the hypothesis that the breakout model can explain solar eruptions on a wide range of scales.

  3. Separating limits on preparation versus online processing in multitasking paradigms: Evidence for resource models. (United States)

    Mittelstädt, Victor; Miller, Jeff


    We conducted 2 multitasking experiments to examine the finding that first-task reaction times (RTs) are slower in the psychological refractory period (PRP) paradigm than in the prioritized processing (PP) paradigm. To see whether this difference between the 2 paradigms could be explained entirely by differences in first-task preparation, which would be consistent with the standard response selection bottleneck (RSB) model for multitasking interference, we compared the size of this difference for trials in which a second-task stimulus actually occurred against the size of the difference for trials without any second-task stimulus. The slowing of first-task RTs in the PRP paradigm relative to the PP paradigm was larger when the second-task stimulus appeared than when it did not, indicating that the difference cannot be explained entirely by between-paradigm differences in first-task preparation. Instead, the results suggest that the slowing of first-task RTs in the PRP paradigm relative to the PP paradigm is partly because of differences between paradigms in the online reallocation of processing capacity to tasks. Thus, the present results provide new evidence supporting resource models over the RSB model. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  4. An Organizational Model for Excellence in Healthcare Delivery: Evidence From Winners of the Baldrige Quality Award. (United States)

    Griffith, John R

    Winners of the Baldrige National Quality Award in healthcare have documented top quartile clinical outcomes and patient satisfaction across a variety of American communities and a full spectrum of care. Their results also show high levels of satisfaction among physicians, nurses, and other workers, as well as effective financial performance. The managerial methods they use-collectively, the Baldrige model-are consistent with organizational theory literature and are found across all winners. The winners have sustained excellence after winning and expanded it by acquisition of other healthcare organizations.The model differs substantially from traditional management approaches in healthcare delivery. It is a comprehensive program that emphasizes a shared focus on excellence, systematically responsive management, evidence-based medicine, multidimensional measures and negotiated goals, improvement of work processes, thorough training, and extensive rewards. The model could be expanded on a much larger scale. Doing so successfully would substantially improve the quality and cost of healthcare, as well as the satisfaction and commitment of care providers and other staff. The opportunity deserves further study and trial by large healthcare delivery systems, insurers, and consulting companies.

  5. Estimating ambiguity preferences and perceptions in multiple prior models: Evidence from the field (United States)

    Dimmock, Stephen G.; Kouwenberg, Roy; Mitchell, Olivia S.; Peijnenburg, Kim


    We develop a tractable method to estimate multiple prior models of decision-making under ambiguity. In a representative sample of the U.S. population, we measure ambiguity attitudes in the gain and loss domains. We find that ambiguity aversion is common for uncertain events of moderate to high likelihood involving gains, but ambiguity seeking prevails for low likelihoods and for losses. We show that choices made under ambiguity in the gain domain are best explained by the α-MaxMin model, with one parameter measuring ambiguity aversion (ambiguity preferences) and a second parameter quantifying the perceived degree of ambiguity (perceptions about ambiguity). The ambiguity aversion parameter α is constant and prior probability sets are asymmetric for low and high likelihood events. The data reject several other models, such as MaxMin and MaxMax, as well as symmetric probability intervals. Ambiguity aversion and the perceived degree of ambiguity are both higher for men and for the college-educated. Ambiguity aversion (but not perceived ambiguity) is also positively related to risk aversion. In the loss domain, we find evidence of reflection, implying that ambiguity aversion for gains tends to reverse into ambiguity seeking for losses. Our model’s estimates for preferences and perceptions about ambiguity can be used to analyze the economic and financial implications of such preferences. PMID:26924890

  6. Evidence of neuroprotective effects of saffron and crocin in a Drosophila model of parkinsonism. (United States)

    Rao, Sriranjini Venkat; Muralidhara; Yenisetti, Sarat Chandra; Rajini, Padmanabhan S


    Evidence suggests that saffron and its major bioactives exhibit significant neuromodulatory effects in various animal models. However, specific data related to their efficacy to attenuate oxidative stress and neurotoxicity in animal models of Parkinson's disease (PD) are limited. Hence, we investigated the neuroprotective efficacy of saffron methanolic extract (SME) and its active constituent, crocin (CR) employing a Drosophila model of parkinsonism. We focussed on attenuation of Rotenone (ROT)-induced locomotor phenotype, oxidative stress, mitochondrial dysfunction and neurotoxicity in this model. SME and CR-enrichment significantly reduced ROT (500μM) induced mortality, rescued the locomotor phenotype and diminished the enhanced levels of oxidative stress markers in head/body regions of flies. The reduced levels of reduced glutathione (GSH) and total thiols (TSH) resulting from ROT exposure were significantly restored with concomitant enhancement of the antioxidant enzymes activities. Further, ROT-induced mitochondrial dysfunctions (MTT reduction, activities of SDH and NADH-Cyt C reductase (complexes I-III) enzymes) were markedly attenuated by SME/CR enrichment. While ROT elevated the activity of acetylcholinesterase (AChE) in head/body regions, both the treatments caused marked diminution of AChE activity and restored the dopamine levels suggesting their effectiveness to mitigate cholinergic function. Interestingly, SME/CR enrichment significantly delayed the onset of locomotor deficits and extended life span of flies among ROT (50μM)-stressed flies. In a satellite study, flies provided with SME/CR prophylaxis exhibited marked resistance to an acute Paraquat (PQ) challenge as evidenced by the lower incidence of lethality and improved locomotor phenotype. Taken together, the neuroprotective effects of saffron and crocin in the fly model may be largely attributable to its antioxidant action. Based on our findings, we propose that saffron may be exploited as a

  7. Materials properties utilization in a cumulative mechanical damage function for LMFBR fuel pin failure analysis

    International Nuclear Information System (INIS)

    Jacobs, D.C.


    An overview is presented of one of the fuel-pin analysis techniques used in the CRBRP program, the cumulative mechanical damage function. This technique, as applied to LMFBR's, was developed along with the majority of models used to describe the mechanical properties and environmental behavior of the cladding (i.e., 20 percent cold-worked, 316 stainless steel). As it relates to fuel-pin analyses the Cumulative Mechanical Damage Function (CDF) continually monitors cladding integrity through steady state and transient operation; it is a time dependent function of temperature and stress which reflects the effects of both the prior mechanical history and the variations in mechanical properties caused by exposure to the reactor environment

  8. Higher order net-proton number cumulants dependence on the centrality definition and other spurious effects (United States)

    Sombun, S.; Steinheimer, J.; Herold, C.; Limphirat, A.; Yan, Y.; Bleicher, M.


    We study the dependence of the normalized moments of the net-proton multiplicity distributions on the definition of centrality in relativistic nuclear collisions at a beam energy of \\sqrt{{s}{NN}}=7.7 {GeV}. Using the ultra relativistic quantum molecular dynamics model as event generator we find that the centrality definition has a large effect on the extracted cumulant ratios. Furthermore we find that the finite efficiency for the determination of the centrality introduces an additional systematic uncertainty. Finally, we quantitatively investigate the effects of event-pile up and other possible spurious effects which may change the measured proton number. We find that pile-up alone is not sufficient to describe the data and show that a random double counting of events, adding significantly to the measured proton number, affects mainly the higher order cumulants in most central collisions.

  9. Cumulative Ductility and Hysteretic Behavior of Small Buckling-Restrained Braces

    Directory of Open Access Journals (Sweden)

    Hidajat Sugihardjo


    Full Text Available Cumulative ductility is defined as a ratio of total energy to elastic energy which is dissipated by an element of the structural system during cyclic loading. An element of the structural system is categorized hysteretic if the cumulative ductility factor fulfills certain criteria. This study investigated both analytically and experimentally Small Buckling-Restrained Braces (SBRBs. The core of bracings was modeled using Menegotto-Pinto and bilinear functions. The restrained bracing members were in the shape of square hollow steel section. They were made of the assembly of two L-shaped steel sections. From the experimental study on four SBRB specimens, it was proven that the proposed SBRBs have performed relatively stable hysteretic curves up to two percent of strain and the cumulative ductility factor of 199–450. This value is sufficient for the Buckling-Restrained Brace (BRB elements as elastoplastic structural components. The comparisons of the hysteretic behaviors resulted by SBRB specimens using the Menegotto-Pinto functions and experiments exhibited good agreements, while the amount of energy dissipated by the SBRB specimens using the bilinear model agreed well with the experimental results. Based on the behavior of the experimental hysteretic, implementing the proposed SBRBs as components in ductile truss system is recommended.

  10. The Unemployment-Stock Market Relationship in South Africa: Evidence from Symmetric and Asymmetric Cointegration Models

    Directory of Open Access Journals (Sweden)

    Andrew Phiri


    Full Text Available In this study, we examine linear and nonlinear cointegration and causal relations between unemployment and stock market returns in South Africa using quarterly data collected between 1994:Q1 and 2016:Q1. Our empirical results reveal significant cointegration effects between the time series in both linear and nonlinear models, even though both frameworks ultimately reject the notion of any causal relations between the variables. Collectively, our study rejects the notion of unemployment being a good predictor for stock market returns and neither do developments in the stock market have any effect on the unemployment rate. Such evidence advocates for weak-form efficiency in the JSE equity prices whereby unemployment data cannot help investors to predict the movement of future share prices and further suggests that policymakers cannot rely on stock market development as an avenue towards lowering the prevailingly high levels of unemployment as set in current macroeconomic policy objectives.

  11. Linguistic inter-understanding gives evidence in favor of the mental models theory: Induction and comprehension

    Directory of Open Access Journals (Sweden)

    Miguel López-Astorga


    Full Text Available Linguistic inter-understanding is a communicative phenomenon that is well known and that has been studied in detail. It basically consists of the fact that an individual speaking a language is able to understand another person speaking a different language, and this without deeply knowing this last language or being able to express himself/herself in it. The phenomenon, which is especially frequent in the case of very similar languages, occurs because of certain inferential processes that can happen in the human mind when people try to interpret information in a distinct language. In this way, the main aim of this paper is to show how such processes are very akin to some of those that the mental models theory attributes to the human reasoning ability, and that hence linguistic inter-understanding can be considered as evidence that this last theory is, at least partially, correct.

  12. Febrile seizures - semiology in humans and animal models: evidence of focality and heterogeneity. (United States)

    Neville, Brian G R; Gindner, Diane


    The relationship between febrile seizures and hippocampal sclerosis has been the subject of longstanding discussion. Animal models for prolonged seizures have shown a clear causal relationship with focal limbic features at low dose and hippocampal damage at high dose. Careful history taking of febrile seizure semiology has shown focal early features often with clear temporal lobe elements. This would suggest that many febrile seizures are secondarily generalised hippocampal seizures. There is evidence of varying levels of epileptogenicity in specific infective causes of febrile seizures. Seizure semiology also suggests that a proportion of such seizures may be non-epileptic reflex asystolic attacks. Seizure semiology in febrile seizures deserves closer scrutiny. Copyright 2009 Elsevier B.V. All rights reserved.

  13. Intertwining evidence- and model-based reasoning in physics sensemaking: An example from electrostatics (United States)

    Russ, Rosemary S.; Odden, Tor Ole B.


    Our field has long valued the goal of teaching students not just the facts of physics, but also the thinking and reasoning skills of professional physicists. The complexity inherent in scientific reasoning demands that we think carefully about how we conceptualize for ourselves, enact in our classes, and encourage in our students the relationship between the multifaceted practices of professional science. The current study draws on existing research in the philosophy of science and psychology to advocate for intertwining two important aspects of scientific reasoning: using evidence from experimentation and modeling. We present a case from an undergraduate physics course to illustrate how these aspects can be intertwined productively and describe specific ways in which these aspects of reasoning can mutually reinforce one another in student learning. We end by discussing implications for this work for instruction in introductory physics courses and for research on scientific reasoning at the undergraduate level.

  14. Cumulative assessment : Strategic choices to influence students' study effort

    NARCIS (Netherlands)

    Kerdijk, Wouter; Tio, Rene A.; Mulder, B. Florentine; Cohen-Schotanus, Janke


    Background: It has been asserted that assessment can and should be used to drive students' learning. In the current study, we present a cumulative assessment program in which test planning, repeated testing and compensation are combined in order to influence study effort. The program is aimed at

  15. Cumulative assessment: does it improve students’ knowledge acquisition and retention?

    NARCIS (Netherlands)

    Cecilio Fernandes, Dario; Nagtegaal, Manouk; Noordzij, Gera; Tio, Rene


    Introduction Assessment for learning means changing students’ behaviour regarding their learning. Cumulative assessment has been shown to increase students’ self-study time and spread their study time throughout a course. However, there was no difference regarding students’ knowledge at the end of

  16. How to manage the cumulative flood safety of catchment dams ...

    African Journals Online (AJOL)

    Dam safety is a significant issue being taken seriously worldwide. However, in Australia, although much attention is being devoted to the medium- to large-scale dams, minimal attention is being paid to the serious potential problems associated with smaller dams, particularly the potential cumulative safety threats they pose ...

  17. Detrital Zircon Geochronology: New Evidence for an Old Model for Accretion of the Southwest Baltic Shield. (United States)

    de Haas GJ; Andersen; Vestin


    Disruption of the original crustal architecture as a result of tectonic events often complicates studies of the crustal evolution of Precambrian cratons. Ion-probe U-Pb dating of detrital zircons is one way to circumvent this problem. It yields a "fingerprint" of the source of the metasedimentary host that can be used to tie the host to a counterpart elsewhere. In this study, ion-probe U-Pb dating of detrital zircons from segments of the late Mesoproterozoic Southwest Scandinavian Domain (SSD) of the Baltic Shield provides new evidence for an old model of crustal evolution and tectonic development. Zircon ages for both the pebble and matrix fraction of the Seljord conglomerate, Telemark sector, Norway, show a 1.9-1.7-Ga frequency maximum, as was previously recognized for metasediments from the adjacent Bamble sector. However, the Telemark metasediments lack evidence for significant input of 1.4-1.6-Ga-old crustal material, characteristic of some of the Bamble metasediments. A maximum depositional age of ca. 1450 Ma is inferred for the Seljord conglomerate and a quartzite from the Bamble sector. Definite evidence for significant amounts of pre-1.6-Ga crust in the SSD is absent. Instead, provenance from the early Mesoproterozoic Svecofennian Domain for the 1.9-1.7-Ga crust is proposed, supported by the omnipresence of small amounts of Archean zircons and the distribution of Nd model ages of these and other SSD metasediments. It is proposed that the SSD originally formed a single, continuous belt, fringing the Baltic Shield, with the northernmost segments transported to their current position west of the Oslo rift along north-south-trending shear zones, i.e., at odds with the commonly held view of progressive westward growth of the Baltic Shield. The detrital zircon ages from the Faurefjell quartzite, Rogaland-Vest Agder sector, cluster around 1.65 Ga and reveal a maximum depositional age of 1244+/-40 Ma. Its deviating depositional setting indicates that the Rogaland

  18. The challenges and opportunities in cumulative effects assessment

    International Nuclear Information System (INIS)

    Foley, Melissa M.; Mease, Lindley A.; Martone, Rebecca G.; Prahler, Erin E.; Morrison, Tiffany H.; Murray, Cathryn Clarke; Wojcik, Deborah


    The cumulative effects of increasing human use of the ocean and coastal zone have contributed to a rapid decline in ocean and coastal resources. As a result, scientists are investigating how multiple, overlapping stressors accumulate in the environment and impact ecosystems. These investigations are the foundation for the development of new tools that account for and predict cumulative effects in order to more adequately prevent or mitigate negative effects. Despite scientific advances, legal requirements, and management guidance, those who conduct assessments—including resource managers, agency staff, and consultants—continue to struggle to thoroughly evaluate cumulative effects, particularly as part of the environmental assessment process. Even though 45 years have passed since the United States National Environmental Policy Act was enacted, which set a precedent for environmental assessment around the world, defining impacts, baseline, scale, and significance are still major challenges associated with assessing cumulative effects. In addition, we know little about how practitioners tackle these challenges or how assessment aligns with current scientific recommendations. To shed more light on these challenges and gaps, we undertook a comparative study on how cumulative effects assessment (CEA) is conducted by practitioners operating under some of the most well-developed environmental laws around the globe: California, USA; British Columbia, Canada; Queensland, Australia; and New Zealand. We found that practitioners used a broad and varied definition of impact for CEA, which led to differences in how baseline, scale, and significance were determined. We also found that practice and science are not closely aligned and, as such, we highlight opportunities for managers, policy makers, practitioners, and scientists to improve environmental assessment.

  19. The challenges and opportunities in cumulative effects assessment (United States)

    Foley, Melissa M.; Mease, Lindley A; Martone, Rebecca G; Prahler, Erin E; Morrison, Tiffany H; Clarke Murray, Cathryn; Wojcik, Deborah


    The cumulative effects of increasing human use of the ocean and coastal zone have contributed to a rapid decline in ocean and coastal resources. As a result, scientists are investigating how multiple, overlapping stressors accumulate in the environment and impact ecosystems. These investigations are the foundation for the development of new tools that account for and predict cumulative effects in order to more adequately prevent or mitigate negative effects. Despite scientific advances, legal requirements, and management guidance, those who conduct assessments—including resource managers, agency staff, and consultants—continue to struggle to thoroughly evaluate cumulative effects, particularly as part of the environmental assessment process. Even though 45 years have passed since the United States National Environmental Policy Act was enacted, which set a precedent for environmental assessment around the world, defining impacts, baseline, scale, and significance are still major challenges associated with assessing cumulative effects. In addition, we know little about how practitioners tackle these challenges or how assessment aligns with current scientific recommendations. To shed more light on these challenges and gaps, we undertook a comparative study on how cumulative effects assessment (CEA) is conducted by practitioners operating under some of the most well-developed environmental laws around the globe: California, USA; British Columbia, Canada; Queensland, Australia; and New Zealand. We found that practitioners used a broad and varied definition of impact for CEA, which led to differences in how baseline, scale, and significance were determined. We also found that practice and science are not closely aligned and, as such, we highlight opportunities for managers, policy makers, practitioners, and scientists to improve environmental assessment.


    Cicchetti, Americo; Iacopino, Valentina; Coretti, Silvia; Fiore, Alessandra; Marchetti, Marco; Sampietro-Colom, Laura; Kidholm, Kristian; Wasserfallen, Jean-Blaise; Kahveci, Rabia; Halmesmäki, Esa; Rosenmöller, Magdalene; Wild, Claudia; Kivet, Raul-Allan


    Hospital-based health technology assessment (HB-HTA) is becoming increasingly relevant because of its role in managing the introduction and withdrawal of health technologies. The organizational arrangement in which HB-HTA activities are conducted depends on several contextual factors, although the dominant models have several similarities. The aims of this study were to explore, describe, interpret, and explain seven cases of the application of HB-HTA logic and to propose a classification for HB-HTA organizational models which may be beneficial for policy makers and HTA professionals. The study was part of the AdHopHTA Project, granted under the European 7th Framework Research Programme. A case study methodology was applied to analyze seven HB-HTA initiatives in seven countries, with collection of qualitative and quantitative data. Cross-case analysis was performed within the framework of contingent organizational theory. Evidence showed that some organizational or "structural" variables, namely the level of procedure formalization/structuration and the level of integration with other HTA bodies at the national, regional, and provincial levels, predominantly shape the HB-HTA approach, determining a contingency model of HB-HTA. Crossing the two variables, four options have emerged: integrated specialized HTA unit, stand-alone HTA unit, integrated-essential HTA, independent group unit. No one-best-way approach can be used for HTA at the hospital level. Rather, the characteristics of HTA models depend on many contextual factors. Such conceptualization may aid the diffusion of HB-HTA to inform managerial decision making and clinical practice.

  1. Informed Design of Educational Technology for Teaching and Learning? Towards an Evidence-Informed Model of Good Practice (United States)

    Price, Linda; Kirkwood, Adrian


    The aim of this paper is to model evidence-informed design based on a selective critical analysis of research articles. The authors draw upon findings from an investigation into practitioners' use of educational technologies to synthesise and model what informs their designs. They found that practitioners' designs were often driven by implicit…

  2. Testing Capital Asset Pricing Model: Empirical Evidences from Indian Equity Market

    Directory of Open Access Journals (Sweden)



    Full Text Available The present study examines the Capital Asset Pricing Model (CAPM for the Indian stock market using monthly stock returns from 278 companies of BSE 500 Index listed on the Bombay stock exchange for the period of January 1996 to December 2009. The findings of this study are not substantiating the theory’s basic result that higher risk (beta is associated with higher levels of return. The model does explain, however, excess returns and thus lends support to the linear structure of the CAPM equation. The theory’s prediction for the intercept is that it should equal zero and the slope should equal the excess returns on the market portfolio. The results of the study lead to negate the above hypotheses and offer evidence against the CAPM. The tests conducted to examine the nonlinearity of the relationship between return and betas bolster the hypothesis that the expected return-beta relationship is linear. Additionally, this study investigates whether the CAPM adequately captures all-important determinants of returns including the residual variance of stocks. The results exhibit that residual risk has no effect on the expected returns of portfolios.

  3. Geological evidence and sediment transport modelling for the 1946 and 1960 tsunamis in Shinmachi, Hilo, Hawaii (United States)

    Chagué, Catherine; Sugawara, Daisuke; Goto, Kazuhisa; Goff, James; Dudley, Walter; Gadd, Patricia


    The Japanese community of Shinmachi, established on low-lying land between downtown Hilo and Waiakea, Hawaii, was obliterated by the 1946 Aleutian tsunami but was rebuilt, only to be destroyed again by the 1960 Chilean tsunami. The aim of this study was to find out if any geological evidence of these well documented events had been preserved in the sedimentary record in Wailoa River State Park, which replaced Shinmachi after the 1960 tsunami. This was achieved by collecting cores in the park and performing sedimentological, chronological and geochemical analyses, the latter also processed by principal component analysis. Sediment transport modelling was carried out for both tsunamis, to infer the source of the sediment and areas of deposition on land. The field survey revealed two distinct units within peat and soil, a thin lower unit composed of weathered basalt fragments within mud (Unit 1) and an upper unit dominated by fine volcanic sand within fine silt exhibiting subtle upward fining and coarsening (Unit 2, consisting of Unit 2A and Unit 2B), although these two anomalous units only occur on the western shore of Waiakea Mill Pond. Analysis with an ITRAX core scanner shows that Unit 1 is characterised by high Mn, Fe, Rb, La and Ce counts, combined with elevated magnetic susceptibility. Based on its chemical and sedimentological characteristics, Unit 1 is attributed to a flood event in Wailoa River that occurred around 1520-1660 CE, most probably as a result of a tropical storm. The sharp lower contact of Unit 2 coincides with the appearance of arsenic, contemporaneous with an increase in Ca, Sr, Si, Ti, K, Zr, Mn, Fe, La and Ce. In this study, As is used as a chronological and source material marker, as it is known to have been released into Wailoa River Estuary and Waiakea Mill Pond by the Canec factory between 1932 and 1963. Thus, not only the chemical and sedimentological evidence but also sediment transport modelling, corroborating the historical record

  4. Are trans diagnostic models of eating disorders fit for purpose? A consideration of the evidence for food addiction. (United States)

    Treasure, Janet; Leslie, Monica; Chami, Rayane; Fernández-Aranda, Fernando


    Explanatory models for eating disorders have changed over time to account for changing clinical presentations. The transdiagnostic model evolved from the maintenance model, which provided the framework for cognitive behavioural therapy for bulimia nervosa. However, for many individuals (especially those at the extreme ends of the weight spectrum), this account does not fully fit. New evidence generated from research framed within the food addiction hypothesis is synthesized here into a model that can explain recurrent binge eating behaviour. New interventions that target core maintenance elements identified within the model may be useful additions to a complex model of treatment for eating disorders. Copyright © 2018 John Wiley & Sons, Ltd and Eating Disorders Association.

  5. Cleansing lotion containing tamarind fruit pulp extract. II. Study of cumulative irritation effects in human. (United States)

    Maenthaisong, Ratree; Viyoch, Jarupa; Chaiyakunapruk, Nathorn; Warnnissorn, Prateep


    Cleansing lotion containing extract of tamarind fruit pulp was developed to provide skin a lighter effect. Skin irritation may occur due to keratolytic effect of alpha-hydroxyl acids (AHA) in the tamarind fruit pulp extract. To assess the cumulative irritation effect of cleansing lotion containing tamarind fruit extract with 2% (w/w) tartaric acid on human skin compared with placebo product and de-ionized water. The study design was a single-blinded, randomized side of arm, and controlled study. Three samples, including test product, placebo product, and de-ionized water, were repeatedly applied on the inner forearm of 15 healthy females (aged 28.3 +/- 3.1 years) for 30 min daily for 5 days under semi-occlusive patch. Skin irritation was measured by using visual scoring and instruments such as Tewameter and Mexameter. All measurements were done before application of samples every day from day 1 until day 5. Final measurements were done after the last application for 3 days (day 8). The results obtained from the visual scoring scale indicated no irritation signs and symptoms of test product. Mean differences of transepidermal water loss and erythema values between test product and de-ionized water and between test and placebo products were not statistically significant (P > 0.05). These findings indicate a preliminary safety evidence of our developed cleansing lotion containing the natural AHAs and can be used as cumulative evidence for supporting the future home use study of this product in human.

  6. A Practical Probabilistic Graphical Modeling Tool for Weighing Ecological Risk-Based Evidence (United States)

    Past weight-of-evidence frameworks for adverse ecological effects have provided soft-scoring procedures for judgments based on the quality and measured attributes of evidence. Here, we provide a flexible probabilistic structure for weighing and integrating lines of evidence for e...

  7. Regulators as agents: Modelling personality and power as evidence is brokered to support decisions on environmental risk

    Energy Technology Data Exchange (ETDEWEB)

    Davies, G.J. [Cranfield University, Centre for Environmental Risks and Futures, School of Applied Sciences, Cranfield MK43 0AL (United Kingdom); Kendall, G. [University of Nottingham, School of Computer Science, Nottingham NG8 1BB (United Kingdom); University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor Darul Ehsan (Malaysia); Soane, E. [London School of Economics and Political Science, Department of Management, London WC2A 2AE (United Kingdom); Li, J. [University of Nottingham, School of Computer Science, Nottingham NG8 1BB (United Kingdom); Rocks, S.A.; Jude, S.R. [Cranfield University, Centre for Environmental Risks and Futures, School of Applied Sciences, Cranfield MK43 0AL (United Kingdom); Pollard, S.J.T., E-mail: [Cranfield University, Centre for Environmental Risks and Futures, School of Applied Sciences, Cranfield MK43 0AL (United Kingdom)


    Complex regulatory decisions about risk rely on the brokering of evidence between providers and recipients, and involve personality and power relationships that influence the confidence that recipients may place in the sufficiency of evidence and, therefore, the decision outcome. We explore these relationships in an agent-based model; drawing on concepts from environmental risk science, decision psychology and computer simulation. A two-agent model that accounts for the sufficiency of evidence is applied to decisions about salt intake, animal carcass disposal and radioactive waste. A dynamic version of the model assigned personality traits to agents, to explore their receptivity to evidence. Agents with ‘aggressor’ personality sets were most able to imbue fellow agents with enhanced receptivity (with ‘avoider’ personality sets less so) and clear confidence in the sufficiency of evidence. In a dynamic version of the model, when both recipient and provider were assigned the ‘aggressor’ personality set, this resulted in 10 successful evidence submissions in 71 days, compared with 96 days when both agents were assigned the ‘avoider’ personality set. These insights suggest implications for improving the efficiency and quality of regulatory decision making by understanding the role of personality and power. - Highlights: •The role of personality and power in regulatory decision-making is poorly represented. •We built a rudimentary two-agent model to explore environmental risk decisions. •Our two agent model accounted for decisions about the sufficiency of evidence. •We examined the influence personality and power has on confidence gained. •By giving agents personality we might predict the time taken to reach consensus.

  8. The ASM-NSF Biology Scholars Program: An Evidence-Based Model for Faculty Development

    Directory of Open Access Journals (Sweden)

    Amy L. Chang


    Full Text Available The American Society for Microbiology (ASM established its ASM-NSF (National Science Foundation Biology Scholars Program (BSP to promote undergraduate education reform by 1 supporting biologists to implement evidence-based teaching practices, 2 engaging life science professional societies to facilitate biologists’ leadership in scholarly teaching within the discipline, and 3 participating in a teaching community that fosters disciplinary-level science, technology, engineering, and mathematics (STEM reform. Since 2005, the program has utilized year-long residency training to provide a continuum of learning and practice centered on principles from the scholarship of teaching and learning (SoTL to more than 270 participants (“scholars” from biology and multiple other disciplines. Additionally, the program has recruited 11 life science professional societies to support faculty development in SoTL and discipline-based education research (DBER. To identify the BSP’s long-term outcomes and impacts, ASM engaged an external evaluator to conduct a study of the program’s 2010­–2014 scholars (n = 127 and society partners. The study methods included online surveys, focus groups, participant observation, and analysis of various documents. Study participants indicate that the program achieved its proposed goals relative to scholarship, professional society impact, leadership, community, and faculty professional development. Although participants also identified barriers that hindered elements of their BSP participation, findings suggest that the program was essential to their development as faculty and provides evidence of the BSP as a model for other societies seeking to advance undergraduate science education reform. The BSP is the longest-standing faculty development program sponsored by a collective group of life science societies. This collaboration promotes success across a fragmented system of more than 80 societies representing the life

  9. The ASM-NSF Biology Scholars Program: An Evidence-Based Model for Faculty Development. (United States)

    Chang, Amy L; Pribbenow, Christine M


    The American Society for Microbiology (ASM) established its ASM-NSF (National Science Foundation) Biology Scholars Program (BSP) to promote undergraduate education reform by 1) supporting biologists to implement evidence-based teaching practices, 2) engaging life science professional societies to facilitate biologists' leadership in scholarly teaching within the discipline, and 3) participating in a teaching community that fosters disciplinary-level science, technology, engineering, and mathematics (STEM) reform. Since 2005, the program has utilized year-long residency training to provide a continuum of learning and practice centered on principles from the scholarship of teaching and learning (SoTL) to more than 270 participants ("scholars") from biology and multiple other disciplines. Additionally, the program has recruited 11 life science professional societies to support faculty development in SoTL and discipline-based education research (DBER). To identify the BSP's long-term outcomes and impacts, ASM engaged an external evaluator to conduct a study of the program's 2010-2014 scholars (n = 127) and society partners. The study methods included online surveys, focus groups, participant observation, and analysis of various documents. Study participants indicate that the program achieved its proposed goals relative to scholarship, professional society impact, leadership, community, and faculty professional development. Although participants also identified barriers that hindered elements of their BSP participation, findings suggest that the program was essential to their development as faculty and provides evidence of the BSP as a model for other societies seeking to advance undergraduate science education reform. The BSP is the longest-standing faculty development program sponsored by a collective group of life science societies. This collaboration promotes success across a fragmented system of more than 80 societies representing the life sciences and helps

  10. Framing Climate Goals in Terms of Cumulative CO2-Forcing-Equivalent Emissions (United States)

    Jenkins, S.; Millar, R. J.; Leach, N.; Allen, M. R.


    The relationship between cumulative CO2 emissions and CO2-induced warming is determined by the Transient Climate Response to Emissions (TCRE), but total anthropogenic warming also depends on non-CO2 forcing, complicating the interpretation of emissions budgets based on CO2 alone. An alternative is to frame emissions budgets in terms of CO2-forcing-equivalent (CO2-fe) emissions—the CO2 emissions that would yield a given total anthropogenic radiative forcing pathway. Unlike conventional "CO2-equivalent" emissions, these are directly related to warming by the TCRE and need to fall to zero to stabilize warming: hence, CO2-fe emissions generalize the concept of a cumulative carbon budget to multigas scenarios. Cumulative CO2-fe emissions from 1870 to 2015 inclusive are found to be 2,900 ± 600 GtCO2-fe, increasing at a rate of 67 ± 9.5 GtCO2-fe/yr. A TCRE range of 0.8-2.5°C per 1,000 GtC implies a total budget for 0.6°C of additional warming above the present decade of 880-2,750 GtCO2-fe, with 1,290 GtCO2-fe implied by the Coupled Model Intercomparison Project Phase 5 median response, corresponding to 19 years' CO2-fe emissions at the current rate.

  11. Childhood cumulative risk and obesity: the mediating role of self-regulatory ability. (United States)

    Evans, Gary W; Fuller-Rowell, Thomas E; Doan, Stacey N


    We tested whether early childhood risk exposures are related to weight gain in adolescence and evaluate an underlying mechanism, self-regulatory behavior, for the risk-obesity link. Cumulative risk exposure to 9 sociodemographic (eg, poverty), physical (eg, substandard housing), and psychosocial (eg, family turmoil) stressors was assessed in 244 nine-year-old children. BMI was calculated at age 9 and then 4 years later. At age 9, children's ability to delay gratification as an index of self-regulatory behavior was assessed. Path analyses were then estimated to evaluate our mediational model (Cumulative risk → Self-regulation → BMI) over a 4-year period in a prospective, longitudinal design. Nine-year-old children exposed to a greater accumulation of multiple risk factors show larger gains in adiposity over the next four year period, net of their initial BMI. These gains in BMI during early adolescence are largely accounted for by deteriorated self-regulatory abilities among children facing more cumulative risks. Early childhood risk exposure leads to larger gains in BMI in adolescence. Given the importance of childhood adiposity to the development of obesity later in life, understanding the underlying mechanisms that link early experience to weight gain is an essential task. Deficiencies in self-regulation in response to chronic stress appears to be an important agent in the obesity epidemic.

  12. The joint structure of normal and pathological personality: further evidence for a dimensional model. (United States)

    Hengartner, Michael P; Ajdacic-Gross, Vladeta; Rodgers, Stephanie; Müller, Mario; Rössler, Wulf


    The literature proposes a joint structure of normal and pathological personality with higher-order factors mainly based on the five-factor model of personality (FFM). The purpose of the present study was to examine the joint structure of the FFM and the DSM-IV personality disorders (PDs) and to discuss this structure with regard to higher-order domains commonly reported in the literature. We applied a canonical correlation analysis, a series of principal component analyses with oblique Promax rotation and a bi-factor analysis with Geomin rotation on 511 subjects of the general population of Zurich, Switzerland, using data from the ZInEP Epidemiology Survey. The 5 FFM traits and the 10 DSM-IV PD dimensions shared 77% of total variance. Component extraction tests pointed towards a two- and three-component solution. The two-component solution comprised a first component with strong positive loadings on neuroticism and all 10 PD dimensions and a second component with strong negative loadings on extraversion and openness and positive loadings on schizoid and avoidant PDs. The three-component solution added a third component with strong positive loadings on conscientiousness and agreeableness and a negative loading on antisocial PD. The bi-factor model provided evidence for 1 general personality dysfunction factor related to neuroticism and 5 group factors, although the interpretability of the latter was limited. Normal and pathological personality domains are not isomorphic or superposable, although they share a substantial proportion of variance. The two and three higher-order domains extracted in the present study correspond well to equivalent factor-solutions reported in the literature. Moreover, these superordinate factors can consistently be integrated within a hierarchical structure of alternative four- and five-factor models. The top of the hierarchy presumably constitutes a general personality dysfunction factor which is closely related to neuroticism. © 2014.

  13. Cumulative risk assessment of the exposure to pyrethroids through fruits consumption in China - Based on a 3-year investigation. (United States)

    Li, Zhixia; Nie, Jiyun; Lu, Zeqi; Xie, Hanzhong; Kang, Lu; Chen, Qiusheng; Li, An; Zhao, Xubo; Xu, Guofeng; Yan, Zhen


    In the present study, the long-term and short-term cumulative risks of pyrethroids exposured for the Chinese general population and children through fruits consumption were evaluated. A total of 1450 fruit samples and seven pyrethroids were included based on the pesticide residues monitoring programme of China from 2013 to 2015. The exposure was estimated using both deterministic approach and semi-probabilistic model for comparison. The hazard index approach was used to assess cumulative risk. 26% of samples contained pyrethroid residues with concentrations ranged from 0.0050 mg/kg to 1.2 mg/kg, of which 30% simultaneously with 2-4 mixture residues. Results demonstrated that the cumulative health risks were extremely low for both general population and children (1-6 years old) of China in the long term. Acute risk estimations calculated by deterministic method were several or many times overestimated than the results based on semi-probabilistic method. Acute cumulative exposure of children to pyrethroid compounds in 0.76% samples were exceeded 1 in worst case scenario. More detailed assessments with adequate data in the future use probabilistic method is expected to reduce the uncertainties of cumulative dietary exposure. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Cumulative organic anion transporter-mediated drug-drug interaction potential of multiple components in salvia miltiorrhiza (danshen) preparations. (United States)

    Wang, Li; Venitz, Jürgen; Sweet, Douglas H


    To evaluate organic anion transporter-mediated drug-drug interaction (DDI) potential for individual active components of Danshen (Salvia miltiorrhiza) vs. combinations using in vitro and in silico approaches. Inhibition profiles for single Danshen components and combinations were generated in stably-expressing human (h)OAT1 and hOAT3 cells. Plasma concentration-time profiles for compounds were estimated from in vivo human data using an i.v. two-compartment model (with first-order elimination). The cumulative DDI index was proposed as an indicator of DDI potential for combination products. This index was used to evaluate the DDI potential for Danshen injectables from 16 different manufacturers and 14 different lots from a single manufacturer. The cumulative DDI index predicted in vivo inhibition potentials, 82% (hOAT1) and 74% (hOAT3), comparable with those observed in vitro, 72 ± 7% (hOAT1) and 81 ± 10% (hOAT3), for Danshen component combinations. Using simulated unbound Cmax values, a wide range in cumulative DDI index between manufacturers, and between lots, was predicted. Many products exhibited a cumulative DDI index > 1 (50% inhibition). Danshen injectables will likely exhibit strong potential to inhibit hOAT1 and hOAT3 function in vivo. The proposed cumulative DDI index might improve prediction of DDI potential of herbal medicines or pharmaceutical preparations containing multiple components.

  15. Estimation of 305 Day Milk Yield from Cumulative Monthly and Bimonthly Test Day Records in Indonesian Holstein Cattle (United States)

    Rahayu, A. P.; Hartatik, T.; Purnomoadi, A.; Kurnianto, E.


    The aims of this study were to estimate 305 day first lactation milk yield of Indonesian Holstein cattle from cumulative monthly and bimonthly test day records and to analyze its accuracy.The first lactation records of 258 dairy cows from 2006 to 2014 consisted of 2571 monthly (MTDY) and 1281 bimonthly test day yield (BTDY) records were used. Milk yields were estimated by regression method. Correlation coefficients between actual and estimated milk yield by cumulative MTDY were 0.70, 0.78, 0.83, 0.86, 0.89, 0.92, 0.94 and 0.96 for 2-9 months, respectively, meanwhile by cumulative BTDY were 0.69, 0.81, 0.87 and 0.92 for 2, 4, 6 and 8 months, respectively. The accuracy of fitting regression models (R2) increased with the increasing in the number of cumulative test day used. The used of 5 cumulative MTDY was considered sufficient for estimating 305 day first lactation milk yield with 80.6% accuracy and 7% error percentage of estimation. The estimated milk yield from MTDY was more accurate than BTDY by 1.1 to 2% less error percentage in the same time.

  16. An Ensemble Deep Convolutional Neural Network Model with Improved D-S Evidence Fusion for Bearing Fault Diagnosis. (United States)

    Li, Shaobo; Liu, Guokai; Tang, Xianghong; Lu, Jianguang; Hu, Jianjun


    Intelligent machine health monitoring and fault diagnosis are becoming increasingly important for modern manufacturing industries. Current fault diagnosis approaches mostly depend on expert-designed features for building prediction models. In this paper, we proposed IDSCNN, a novel bearing fault diagnosis algorithm based on ensemble deep convolutional neural networks and an improved Dempster-Shafer theory based evidence fusion. The convolutional neural networks take the root mean square (RMS) maps from the FFT (Fast Fourier Transformation) features of the vibration signals from two sensors as inputs. The improved D-S evidence theory is implemented via distance matrix from evidences and modified Gini Index. Extensive evaluations of the IDSCNN on the Case Western Reserve Dataset showed that our IDSCNN algorithm can achieve better fault diagnosis performance than existing machine learning methods by fusing complementary or conflicting evidences from different models and sensors and adapting to different load conditions.

  17. Evaluation of cumulative PCB exposure estimated by a job exposure matrix versus PCB serum concentrations (United States)

    Ruder, Avima M.; Succop, Paul; Waters, Martha A.


    Although polychlorinated biphenyls (PCBs) have been banned in many countries for more than three decades, exposures to PCBs continue to be of concern due to their long half-lives and carcinogenic effects. In National Institute for Occupational Safety and Health studies, we are using semiquantitative plant-specific job exposure matrices (JEMs) to estimate historical PCB exposures for workers (n=24,865) exposed to PCBs from 1938 to 1978 at three capacitor manufacturing plants. A subcohort of these workers (n=410) employed in two of these plants had serum PCB concentrations measured at up to four times between 1976 and 1989. Our objectives were to evaluate the strength of association between an individual worker’s measured serum PCB levels and the same worker’s cumulative exposure estimated through 1977 with the (1) JEM and (2) duration of employment, and to calculate the explained variance the JEM provides for serum PCB levels using (3) simple linear regression. Consistent strong and statistically significant associations were observed between the cumulative exposures estimated with the JEM and serum PCB concentrations for all years. The strength of association between duration of employment and serum PCBs was good for highly chlorinated (Aroclor 1254/HPCB) but not less chlorinated (Aroclor 1242/LPCB) PCBs. In the simple regression models, cumulative occupational exposure estimated using the JEMs explained 14–24 % of the variance of the Aroclor 1242/LPCB and 22–39 % for Aroclor 1254/HPCB serum concentrations. We regard the cumulative exposure estimated with the JEM as a better estimate of PCB body burdens than serum concentrations quantified as Aroclor 1242/LPCB and Aroclor 1254/HPCB. PMID:23475397

  18. An approach for deriving growth equations for quantities exhibiting cumulative growth based on stochastic interpretation (United States)

    Moriguchi, Kai


    Existing growth equations have been derived by hypothesizing the growth rate as self-referencing. Although that hypothesis is appropriate for quantities with growth directly restricted to themselves, it requires the solution of differential equations that are difficult to be derived. However, for quantities of growth that are indirectly related to themselves, and for quantities that exhibit cumulative growth, such as growth of diameter or volume of trees with lignification, ordinary growth models with assumptions that include self-referencing or implied catabolism terms might not be appropriate. For such quantities, the author proposes an approach for derivation of growth models based on stochastic and microscopic interpretation. Results show that ordinary growth models can be interpreted from the perspective. The approach enables one to derive growth functions without solving differential equations. Based on that approach, growth functions are derived by integrating cumulative distribution functions. Three growth functions are generated using reasonable probability distributions. The fitness of the generated growth functions for real diameter growth data was compared with that of generalized ordinary growth models. Results show that the presented approach has high ability to generate growth models that fit data much better than ordinary growth models for a given number of parameters.

  19. Cumulative Risks of Foster Care Placement for Danish Children

    DEFF Research Database (Denmark)

    Fallesen, Peter; Emanuel, Natalia; Wildeman, Christopher


    foster care placement is salient in other contexts. In this article, we provide companion estimates to those provided in recent work on the US by using Danish registry data and synthetic cohort life tables to show how high and unequally distributed the cumulative risk of foster care placement...... is for Danish children. Results suggest that at the beginning of the study period (in 1998) the cumulative risk of foster care placement for Danish children was roughly in line with the risk for American children. Yet, by the end of the study period (2010), the risk had declined to half the risk for American...... (especially at the beginning of the study period), the age-specific risk profiles are markedly different, with higher risks for older Danish children than for older American children....

  20. Spin effects at fragmentation of polarized deuterons into cumulative pions

    International Nuclear Information System (INIS)

    Afanasiev, S.; Arkhipov, V.; Bondarev, V.; Isupov, A.; Khrenov, A.; Kirillov, D.; Ladygin, V.; Litvinenko, A.; Malakhov, A.; Pilipenko, Yu.; Reznikov, S.; Rukoyatkin, P.; Zolin, L.; Daito, I.; Horikawa, N.; Wakai, A.; Doushita, N.; Fukui, S.; Iwata, T.; Kondo, K.


    Tensor analyzing power T 20 of the reaction d-vectorA→π(0 deg.)X was measured in the fragmentation of 9 GeV deuterons into points with the momenta from 3.5 to 5.3 GeV/c at hydrogen, beryllium and carbon targets. This momentum range corresponds to region of cumulative pion production The values of T 20 are found to be small and consistent with positive values in contradiction with the Impulse Approximation calculations based on assuming a direct mechanism of pion production (NN→NNπ). New data on tensor Ayy analyzing power for pion production at the non-zero angle (θ π =135,180mr) with pion transverse momenta up to P t =0.8 GeV/c are presented. Ayy increases with rise of P t in the cumulative region

  1. Experience of cumulative effects assessment in the UK

    Directory of Open Access Journals (Sweden)

    Piper Jake


    Full Text Available Cumulative effects assessment (CEA is a development of environmental impact assessment which attempts to take into account the wider picture of what impacts may affect the environment as a result of either multiple or linear projects, or development plans. CEA is seen as a further valuable tool in promoting sustainable development. The broader canvas upon which the assessment is made leads to a suite of issues such as complexity in methods and assessment of significance, the desirability of co-operation between developers and other parties, new ways of addressing mitigation and monitoring. After outlining the legislative position and the process of CEA, this paper looks at three cases studies in the UK where cumulative assessment has been carried out - the cases concern wind farms, major infrastructure and off-shore developments.

  2. Cumulative occupational lumbar load and lumbar disc disease – results of a German multi-center case-control study (EPILIFT

    Directory of Open Access Journals (Sweden)

    Michaelis Martina


    Full Text Available Abstract Background The to date evidence for a dose-response relationship between physical workload and the development of lumbar disc diseases is limited. We therefore investigated the possible etiologic relevance of cumulative occupational lumbar load to lumbar disc diseases in a multi-center case-control study. Methods In four study regions in Germany (Frankfurt/Main, Freiburg, Halle/Saale, Regensburg, patients seeking medical care for pain associated with clinically and radiologically verified lumbar disc herniation (286 males, 278 females or symptomatic lumbar disc narrowing (145 males, 206 females were prospectively recruited. Population control subjects (453 males and 448 females were drawn from the regional population registers. Cases and control subjects were between 25 and 70 years of age. In a structured personal interview, a complete occupational history was elicited to identify subjects with certain minimum workloads. On the basis of job task-specific supplementary surveys performed by technical experts, the situational lumbar load represented by the compressive force at the lumbosacral disc was determined via biomechanical model calculations for any working situation with object handling and load-intensive postures during the total working life. For this analysis, all manual handling of objects of about 5 kilograms or more and postures with trunk inclination of 20 degrees or more are included in the calculation of cumulative lumbar load. Confounder selection was based on biologic plausibility and on the change-in-estimate criterion. Odds ratios (OR and 95% confidence intervals (CI were calculated separately for men and women using unconditional logistic regression analysis, adjusted for age, region, and unemployment as major life event (in males or psychosocial strain at work (in females, respectively. To further elucidate the contribution of past physical workload to the development of lumbar disc diseases, we performed lag

  3. Cumulative prospect theory and mean variance analysis. A rigorous comparison


    Hens, Thorsten; Mayer, Janos


    We compare asset allocations derived for cumulative prospect theory(CPT) based on two different methods: Maximizing CPT along the mean–variance efficient frontier and maximizing it without that restriction. We find that with normally distributed returns the difference is negligible. However, using standard asset allocation data of pension funds the difference is considerable. Moreover, with derivatives like call options the restriction to the mean-variance efficient frontier results in a siza...

  4. Heavy metal cumulation in crops after the sewage sludge application

    Directory of Open Access Journals (Sweden)

    Gondová Andrea


    Full Text Available During 1995 - 1996 the crops samples after the sewage sludge application were collected. The heavy metals cumulation in investigated crops from Bardejov increased in order: Zn > Cu > Pb > Ni > Cr > Cd and Banská Bystrica : Zn > Cu > Cr > Ni > Pb > Cd. Heavy metals contents after the sewage sludge application were increased in comparison with the highest admissible concentration in eatable part of crops. The sewage sludge application were not recommended in soils for the growth of vegetables

  5. Cumulative incidence rates of the mucopolysaccharidoses in Germany. (United States)

    Baehner, F; Schmiedeskamp, C; Krummenauer, F; Miebach, E; Bajbouj, M; Whybra, C; Kohlschütter, A; Kampmann, C; Beck, M


    In order to estimate the cumulative incidence rates of the mucopolysaccharidoses (MPS) in Germany, a retrospective epidemiological survey covering the period between 1980 and 1995 was implemented. Multiple ascertainment sources were used to identify affected patients. A prevalence of approximately 0.69 cases per 100,000 births was obtained for MPS I (Hurler phenotype). Within the study period, 4 patients with Hurler/Scheie phenotype and 7 cases with Scheie disease were detected. The cumulative incidence for MPS II (Hunter syndrome) was estimated as 0.64 cases per 100,000 births (1.3 cases per 100,000 male live births); that for MPS III (Sanfilippo syndrome types A, B and C) as 1.57 cases in 100,000 births; that for MPS IV A (Morquio syndrome) as 0.38 cases in 100,000; and that for MPS VI (Maroteaux-Lamy syndrome) as 0.23 cases per 100,000 births. Two cases of MPS IVB (beta-galactosidase deficiency) have been identified, but no patients with MPS VII or MPS IX. A relatively high number of patients with MPS IIIB, MPS IVA and MPS VI were of Turkish origin. The crude rate for all types of mucopolysaccharidoses is approximately 3.53 cases in 100,000 live births. The cumulative incidence pattern of MPS in Germany was compared with the corresponding rates among other industrial nations obtained from recent literature: the crude cumulative rates for all types of mucopolysaccharidoses (3.4-4.5 in 100,000 live births) were similar among all published populations; however, different frequencies of the various forms of MPS were observed.

  6. Psoriasis: is the impairment to a patient's life cumulative? (United States)

    Kimball, A B; Gieler, U; Linder, D; Sampogna, F; Warren, R B; Augustin, M


    Psoriasis is associated with significant physical and psychological burden affecting all facets of a patient's life--relationships, social activities, work and emotional wellbeing. The cumulative effect of this disability may be self-perpetuating social disconnection and failure to achieve a 'full life potential' in some patients. Health-related quality of life studies have quantified the burden of psoriasis providing predominantly cross-sectional data and point-in-time images of patients' lives rather than assessing the possible cumulative disability over a patient's lifetime. However, social and economic outcomes indicate there are likely negative impacts that accumulate over time. To capture the cumulative effect of psoriasis and its associated co-morbidities and stigma over a patient's life course, we propose the concept of 'Cumulative Life Course Impairment' (CLCI). CLCI results from an interaction between (A) the burden of stigmatization, and physical and psychological co-morbidities and (B) coping strategies and external factors. Several key aspects of the CLCI concept are supported by data similar to that used in health-related quality of life assessments. Future research should focus on (i) establishing key components of CLCI and determining the mechanisms of impairment through longitudinal or retrospective case-control studies, and (ii) assessing factors that put patients at increased risk of developing CLCI. In the future, this concept may lead to a better understanding of the overall impact of psoriasis, help identify more vulnerable patients, and facilitate more appropriate treatment decisions or earlier referrals. To our knowledge, this is a first attempt to apply and develop concepts from 'Life Course Epidemiology' to psoriasis research.

  7. Cumulative culture can emerge from collective intelligence in animal groups


    Sasaki, Takao; Biro, Dora


    Studies of collective intelligence in animal groups typically overlook potential improvement through learning. Although knowledge accumulation is recognised as a major advantage of group living within the framework of Cumulative Cultural Evolution (CCE), the interplay between CCE and collective intelligence has remained unexplored. Here, we use homing pigeons to investigate whether the repeated removal and replacement of individuals in experimental groups (a key method in testing for CCE) alt...

  8. Cumulative Risk Assessment Toolbox: Methods and Approaches for the Practitioner

    Directory of Open Access Journals (Sweden)

    Margaret M. MacDonell


    Full Text Available The historical approach to assessing health risks of environmental chemicals has been to evaluate them one at a time. In fact, we are exposed every day to a wide variety of chemicals and are increasingly aware of potential health implications. Although considerable progress has been made in the science underlying risk assessments for real-world exposures, implementation has lagged because many practitioners are unaware of methods and tools available to support these analyses. To address this issue, the US Environmental Protection Agency developed a toolbox of cumulative risk resources for contaminated sites, as part of a resource document that was published in 2007. This paper highlights information for nearly 80 resources from the toolbox and provides selected updates, with practical notes for cumulative risk applications. Resources are organized according to the main elements of the assessment process: (1 planning, scoping, and problem formulation; (2 environmental fate and transport; (3 exposure analysis extending to human factors; (4 toxicity analysis; and (5 risk and uncertainty characterization, including presentation of results. In addition to providing online access, plans for the toolbox include addressing nonchemical stressors and applications beyond contaminated sites and further strengthening resource accessibility to support evolving analyses for cumulative risk and sustainable communities.

  9. Multiway Filtering Based on Fourth-Order Cumulants

    Directory of Open Access Journals (Sweden)

    Salah Bourennane


    Full Text Available We propose a new multiway filtering based on fourth-order cumulants for the denoising of noisy data tensor with correlated Gaussian noise. The classical multiway filtering is based on the TUCKALS3 algorithm that computes a lower-rank tensor approximation. The presented method relies on the statistics of the analyzed multicomponent signal. We first recall how the well-known lower rank-(K1,…,KN tensor approximation processed by TUCKALS3 alternating least square algorithm exploits second-order statistics. Then, we propose to introduce the fourth-order statistics in the TUCKALS3-based method. Indeed, the use of fourth-order cumulants enables to remove the Gaussian components of an additive noise. In the presented method the estimation of the n-mode projector on the n-mode signal subspace are built from the eigenvectors associated with the largest eigenvalues of a fourth-order cumulant slice matrix instead of a covariance matrix. Each projector is applied by means of the n-mode product operator on the n-mode of the data tensor. The qualitative results of the improved multiway TUCKALS3-based filterings are shown for the case of noise reduction in a color image and multicomponent seismic data.

  10. Cumulative trauma, PTSD and dissociation among Ethiopian refugees in Israel. (United States)

    Finklestein, Michal; Solomon, Zahava


    The aim of this study was to examine the exposure of Ethiopian refugees to pre-, peri- and post-migration stressful events and their implications for both posttraumatic stress disorder (PTSD) and dissociation. A random sample (N = 478) of three groups of refugees took part in the research ("Moses" immigrants, 1984, n = 165; "Solomon" immigrants, 1991, n = 169; "Family Reunification" immigrants, 1995, n = 144). Exposure to stressful events and posttraumatic symptoms were assessed via the Harvard Trauma Questionnaire (HTQ). Post-migration difficulties were assessed via the Post Migration Living Difficulties (PMLD) scale. Dissociation was evaluated using the Dissociation Experience Scale (DES). Significant differences were found among the groups in the rates of PTSD (27%, 15%, and 26%, respectively), but no differences were found in dissociation. A significant relationship was found between PTSD symptoms and cumulative trauma among the three groups, but no such relationship was found between dissociation and cumulative trauma. The differences among the groups were discussed in light of the unique characteristics of cumulative trauma, PTSD and dissociation among Ethiopian refugees.

  11. Autonomous Magneto-Cumulative Energy Source Based on Permanent Magnets (United States)

    Gurin, V. E.; Boriskin, A. S.; Vlasov, Yu. V.; Golosov, S. N.; Dimant, E. M.; Demidov, V. A.; Kazakov, S. A.; Kazakova, N. R.; Klimashov, M. V.; Korolev, P. V.; Kutumov, S. V.; Pikar, A. S.; Romanov, A. P.; Shapovalov, E. V.; Shibitov, Yu. M.; Shchetnikov, E. I.; Yanenko, V. A.


    In the paper we describe a design of autonomous source of electromagnetic energy with initial field, created by permanent barium oxide magnets and present results of its tests. The energy source consists of magnetic system with initial energy of 1 J, helical magneto-cumulative generator with helix diameter of 50 mm, amplifying the field energy in 130 times, and transforming unit for a load matching. At peak power on helical generator of 66 MW, the voltage of 16 kV was obtained at inductive load of 40 μH. Weight of the energy autonomous source is 5 kg, HE-charge mass is 100 g. Several variants of magnetic systems were tested. Comparison of the magneto-cumulative generator operation, powered from permanent magnets and powered from capacitor bank was carried out. Optimizing the magnetic system with numerical methods the authors managed to get almost identical distribution of the fields in the generators. Finally, the generator based on permanent magnets operates and provides similar output characteristics as the generator powered from the capacitor bank. In contrast to other magneto-cumulative energy sources powered, for example, from an accumulator or piezo-generator, this source, based on permanent magnets, has higher specific energy characteristics, does not require any switching elements and always ready for operation.

  12. On weighted cumulative residual Tsallis entropy and its dynamic version (United States)

    Khammar, A. H.; Jahanshahi, S. M. A.


    Recently, Sati and Gupta (2015) have introduced a generalized cumulative residual entropy based on the non-additive Tsallis entropy. The cumulative residual entropy, introduced by Rao et al. (2004) is a generalized measure of uncertainty which is applied in reliability and image alignment and non-additive measures of entropy. This entropy finds justifications in many physical, biological and chemical phenomena. In this paper, we derive the weighted form of this measure and call it Weighted Cumulative Residual Tsallis Entropy (WCRTE). Being a "length-biased" shift-dependent information measure, WCRTE is related to the differential information in which higher weight is assigned to large values of observed random variables. Based on the dynamic version of this new information measure, we propose ageing classes and it is shown that it can uniquely determine the survival function and Rayleigh distribution. Several properties, including linear transformations, bounds and related results to stochastic orders are obtained for these measures. Also, we identify classes of distributions in which some well-known distributions are maximum dynamic version of WCRTE. The empirical WCRTE is finally proposed to estimate the new information measure.

  13. Statistical Modeling of Extreme Values and Evidence of Presence of Dragon King (DK) in Solar Wind (United States)

    Gomes, T.; Ramos, F.; Rempel, E. L.; Silva, S.; C-L Chian, A.


    The solar wind constitutes a nonlinear dynamical system, presenting intermittent turbulence, multifractality and chaotic dynamics. One characteristic shared by many such complex systems is the presence of extreme events, that play an important role in several Geophysical phenomena and their statistical characterization is a problem of great practical relevance. This work investigates the presence of extreme events in time series of the modulus of the interplanetary magnetic field measured by Cluster spacecraft on February 2, 2002. One of the main results is that the solar wind near the Earth's bow shock can be modeled by the Generalized Pareto (GP) and Generalized Extreme Values (GEV) distributions. Both models present a statistically significant positive shape parameter which implyies a heavy tail in the probability distribution functions and an unbounded growth in return values as return periods become too long. There is evidence that current sheets are the main responsible for positive values of the shape parameter. It is also shown that magnetic reconnection at the interface between two interplanetary magnetic flux ropes in the solar wind can be considered as Dragon Kings (DK), a class of extreme events whose formation mechanisms are fundamentally different from others. As long as magnetic reconnection can be classified as a Dragon King, there is the possibility of its identification and even its prediction. Dragon kings had previously been identified in time series of financial crashes, nuclear power generation accidents, stock market and so on. It is believed that they are associated with the occurrence of extreme events in dynamical systems at phase transition, bifurcation, crises or tipping points.

  14. Evidence evaluation in fingerprint comparison and automated fingerprint identification systems--Modeling between finger variability. (United States)

    Egli Anthonioz, N M; Champod, C


    In the context of the investigation of the use of automated fingerprint identification systems (AFIS) for the evaluation of fingerprint evidence, the current study presents investigations into the variability of scores from an AFIS system when fingermarks from a known donor are compared to fingerprints that are not from the same source. The ultimate goal is to propose a model, based on likelihood ratios, which allows the evaluation of mark-to-print comparisons. In particular, this model, through its use of AFIS technology, benefits from the possibility of using a large amount of data, as well as from an already built-in proximity measure, the AFIS score. More precisely, the numerator of the LR is obtained from scores issued from comparisons between impressions from the same source and showing the same minutia configuration. The denominator of the LR is obtained by extracting scores from comparisons of the questioned mark with a database of non-matching sources. This paper focuses solely on the assignment of the denominator of the LR. We refer to it by the generic term of between-finger variability. The issues addressed in this paper in relation to between-finger variability are the required sample size, the influence of the finger number and general pattern, as well as that of the number of minutiae included and their configuration on a given finger. Results show that reliable estimation of between-finger variability is feasible with 10,000 scores. These scores should come from the appropriate finger number/general pattern combination as defined by the mark. Furthermore, strategies of obtaining between-finger variability when these elements cannot be conclusively seen on the mark (and its position with respect to other marks for finger number) have been presented. These results immediately allow case-by-case estimation of the between-finger variability in an operational setting. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  15. Modelling university human capital formation and measuring its efficiency: evidence from Florence University

    Directory of Open Access Journals (Sweden)

    Guido Ferrari


    Full Text Available In this paper, an analysis of the technical efficiency in the formation of 2,236 graduates in 1998 in the University of Florence, that is, in the university human capital formation, is performed, by modelling the production process as one in which the student produces himself as a graduate. The tool utilized is the DEA methodology, under the hypothesis of variable returns to scale. The production factors are represented by a set of human and capital resources provided by the faculties, along with individual factors represented by secondary school diploma score and by the length of university study. The analysis is conducted both for the overall graduates, and at a faculty level, in order to emphasize the contribution provided by the latter to efficiency. There is evidence that the students graduated with an average efficiency greater than 90% and therefore with an unexploited productive capacity lower than 10%. At a faculty level, Formation Science appears to be the most efficient, whereas Economics is the less efficient one. By and large, the contribution to efficiency provided by faculties is greater than that brought by students individual characteristics.

  16. Organizational transformation: a model for joint optimization of culture change and evidence-based design. (United States)

    Hamilton, D Kirk; Orr, Robin Diane; Raboin, W Ellen


    Healthcare organizations face continuous and accelerating external change and thus must be prepared to manage their own change initiatives proactively. Given that many believe that the U.S. healthcare system is broken and most healthcare organizations are dealing with pervasive problems, some organizations may choose to seek transformational change to achieve the six aims identified by the Institute of Medicine: healthcare that is safe, effective, patient-centered, timely, efficient, and equitable. Transformational change will almost certainly involve organizational culture. Culture change may be most effective when linked to other organizational change initiatives such as organizational strategy, structure, policies, procedures, and recruiting. Significant organizational change often requires accompanying facility change. There is an interdependent relationship between facility design and organizational culture. They affect each other and both impact organizational performance. Sociotechnical theory promotes joint optimization of the social (culture) and technical (facilities) aspects of an organization to achieve sustained positive change. To achieve organizational transformation and to sustain positive change, organizations must be prepared to adopt collaborative efforts in culture change and facility design. The authors propose a model for accomplishing joint optimization of culture change and evidence-based facility design.

  17. Maternal Obesity and Developmental Programming of Metabolic Disorders in Offspring: Evidence from Animal Models

    Directory of Open Access Journals (Sweden)

    M. Li


    Full Text Available The incidence of obesity and overweight has reached epidemic proportions in the developed world as well as in those countries transitioning to first world economies, and this represents a major global health problem. Concern is rising over the rapid increases in childhood obesity and metabolic disease that will translate into later adult obesity. Although an obesogenic nutritional environment and increasingly sedentary lifestyle contribute to our risk of developing obesity, a growing body of evidence links early life nutritional adversity to the development of long-term metabolic disorders. In particular, the increasing prevalence of maternal obesity and excess maternal weight gain has been associated with a heightened risk of obesity development in offspring in addition to an increased risk of pregnancy-related complications. The mechanisms that link maternal obesity to obesity in offspring and the level of gene-environment interactions are not well understood, but the early life environment may represent a critical window for which intervention strategies could be developed to curb the current obesity epidemic. This paper will discuss the various animal models of maternal overnutrition and their importance in our understanding of the mechanisms underlying altered obesity risk in offspring.

  18. Properties of Reduced Carbon Dioxide Fluid: Evidence from Experimental and Thermodynamic Modeling (United States)

    Simakin, A. G.; Devyatova, V. N.; Salova, T. P.; Zelensky, M. E.


    It is shown experimentally that fluid mostly consisting of CO2 and CO is a good solvent for many petrogenic and ore components under high P-T parameters. Siderite decomposed to oxides and a mixture of CO2 and CO was the source of the fluid in the experiment. It is demonstrated that an ultrapotassic alkaline melt was formed on the oxide matrix as a result of fluid transport of the components of the basaltic melt at 2-5 kbar and 900-1000°C. This melt is characterized by high concentrations of Rb, LREE, Sr, and Ba. The mechanism of solubility of metals in the carbon dioxide-reduced fluid includes the formation of volatile carbonyls. As is evident from thermodynamic modeling, the stability of Ni(CO)4 at high pressure reaches magmatic temperatures. The finding of native nickel in aerosols during eruption of the Tolbachik Volcano in 2012-2013 is explained by decomposition of carbonyl from fluid of a deep origin during magma ascent.

  19. Shexiang Baoxin Pills for Coronary Heart Disease in Animal Models: Preclinical Evidence and Promoting Angiogenesis Mechanism

    Directory of Open Access Journals (Sweden)

    Ke-Jian Zhang


    Full Text Available Shexiang Baoxin Pill (SBP originated from a classical TCM Fufang Suhexiang Pill for chest pain with dyspnea in the Southern Song Dynasty (1107–110 AD. Here, we aimed to evaluate preclinical evidence and possible mechanism of SBP for experimental coronary heart disease (CHD. Studies of SBP in animal models with CHD were identified from 6 databases until April 2016. Study quality for each included article was evaluated according to the CAMARADES 10-item checklist. Outcome measures were myocardial infarction area, vascular endothelial growth factor (VEGF and microvessel count (MVC. All the data were analyzed by using RevMan 5.1 software. As a consequence, 25 studies with 439 animals were identified. The quality score of studies ranged from 2 to 5, with the median of 3.6. Meta-analysis of seven studies showed more significant effects of SBP on the reduction of the myocardial infarction area than the control (P < 0.01. Meta-analysis of eight studies showed significant effects of SBP for increasing VEGF expression compared with the control (P < 0.01. Meta-analysis of 10 studies indicated that SBP significantly improved MVC compared with the control (P < 0.01. In conclusion, these findings preliminarily demonstrated that SBP can reduce myocardial infarction area, exerting cardioprotective function largely through promoting angiogenesis.

  20. 16 CFR 3.43 - Evidence. (United States)


    ... considerations of undue delay, waste of time, or needless presentation of cumulative evidence. Evidence that... so that its use is fair. Hearsay is a statement, other than one made by the declarant while... conducted activity as a regular practice. (d) Presentation of evidence. (1) A party is entitled to present...

  1. Bridging the gap between evidence and policy for infectious diseases: How models can aid public health decision-making

    Directory of Open Access Journals (Sweden)

    Gwenan M. Knight


    Full Text Available The dominant approach to decision-making in public health policy for infectious diseases relies heavily on expert opinion, which often applies empirical evidence to policy questions in a manner that is neither systematic nor transparent. Although systematic reviews are frequently commissioned to inform specific components of policy (such as efficacy, the same process is rarely applied to the full decision-making process. Mathematical models provide a mechanism through which empirical evidence can be methodically and transparently integrated to address such questions. However, such models are often considered difficult to interpret. In addition, models provide estimates that need to be iteratively re-evaluated as new data or considerations arise. Using the case study of a novel diagnostic for tuberculosis, a framework for improved collaboration between public health decision-makers and mathematical modellers that could lead to more transparent and evidence-driven policy decisions for infectious diseases in the future is proposed. The framework proposes that policymakers should establish long-term collaborations with modellers to address key questions, and that modellers should strive to provide clear explanations of the uncertainty of model structure and outputs. Doing so will improve the applicability of models and clarify their limitations when used to inform real-world public health policy decisions.

  2. Bridging the gap between evidence and policy for infectious diseases: How models can aid public health decision-making. (United States)

    Knight, Gwenan M; Dharan, Nila J; Fox, Gregory J; Stennis, Natalie; Zwerling, Alice; Khurana, Renuka; Dowdy, David W


    The dominant approach to decision-making in public health policy for infectious diseases relies heavily on expert opinion, which often applies empirical evidence to policy questions in a manner that is neither systematic nor transparent. Although systematic reviews are frequently commissioned to inform specific components of policy (such as efficacy), the same process is rarely applied to the full decision-making process. Mathematical models provide a mechanism through which empirical evidence can be methodically and transparently integrated to address such questions. However, such models are often considered difficult to interpret. In addition, models provide estimates that need to be iteratively re-evaluated as new data or considerations arise. Using the case study of a novel diagnostic for tuberculosis, a framework for improved collaboration between public health decision-makers and mathematical modellers that could lead to more transparent and evidence-driven policy decisions for infectious diseases in the future is proposed. The framework proposes that policymakers should establish long-term collaborations with modellers to address key questions, and that modellers should strive to provide clear explanations of the uncertainty of model structure and outputs. Doing so will improve the applicability of models and clarify their limitations when used to inform real-world public health policy decisions. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  3. El Carreto o Cumulá - Aspidosperma Dugandii Standl El Carreto o Cumulá - Aspidosperma Dugandii Standl

    Directory of Open Access Journals (Sweden)

    Dugand Armando


    Full Text Available Nombres vulgares: Carreto (Atlántico, Bolívar, Magdalena; Cumulá, Cumulá (Cundinamarca, ToIima. Según el Dr. Emilio Robledo (Lecciones de Bot. ed. 3, 2: 544. 1939 el nombre Carreto también es empleado en Puerto Berrío (Antioquia. El mismo autor (loc. cit. da el nombre Comulá para una especie indeterminada de Viburnum en Mariquita (Tolima y J. M. Duque, refiriendose a la misma planta y localidad (en Bot. Gen. Colomb. 340, 356. 1943 atribuye este nombre vulgar al Aspidosperma ellipticum Rusby.  Sin embargo, las muestras de madera de Cumulá o Comulá que yo he examinado, procedentes de la región de Mariquita -una de las cuales me fue recientemente enviada por el distinguido ictiólogo Sr. Cecil Miles- pertenecen sin duda alguna al A. Dugandii StandI. Por otra parte, Santiago Cortés (FI. Colomb. 206. 1898; ed, 2: 239. 1912 cita el Cumulá "de Anapoima y otros lugares del (rio Magdalena" diciendo que pertenece a las Leguminosas, pero la brevísima descripción que este autor hace de la madera "naranjada y notable por densidad, dureza y resistencia a la humedad", me induce a creer que se trata del mismo Cumula coleccionado recientemente en Tocaima, ya que esta población esta situada a pocos kilómetros de Anapoima. Nombres vulgares: Carreto (Atlántico, Bolívar, Magdalena; Cumulá, Cumulá (Cundinamarca, ToIima. Según el Dr. Emilio Robledo (Lecciones de Bot. ed. 3, 2: 544. 1939 el nombre Carreto también es empleado en Puerto Berrío (Antioquia. El mismo autor (loc. cit. da el nombre Comulá para una especie indeterminada de Viburnum en Mariquita (Tolima y J. M. Duque, refiriendose a la misma planta y localidad (en Bot. Gen. Colomb. 340, 356. 1943 atribuye este nombre vulgar al Aspidosperma ellipticum Rusby.  Sin embargo, las muestras de madera de Cumulá o Comulá que yo he examinado, procedentes de la región de Mariquita -una de las cuales me fue recientemente enviada por el distinguido ictiólogo Sr. Cecil Miles- pertenecen sin

  4. Determining source cumulants in femtoscopy with Gram-Charlier and Edgeworth series

    DEFF Research Database (Denmark)

    Eggers, H. C.; De Kock, M. B.; Schmiegel, Jürgen


    Lowest-order cumulants provide important information on the shape of the emission source in femtoscopy. For the simple case of noninteracting identical particles, we show how the fourth-order source cumulant can be determined from measured cumulants in momentum space. The textbook Gram–Charlier s......Lowest-order cumulants provide important information on the shape of the emission source in femtoscopy. For the simple case of noninteracting identical particles, we show how the fourth-order source cumulant can be determined from measured cumulants in momentum space. The textbook Gram...

  5. Determining source cumulants in femtoscopy with Gram-Charlier and Edgeworth series

    DEFF Research Database (Denmark)

    Schmiegel, Jürgen; Eggers, Hans C.; de Kock, Michiel B

    Lowest-order cumulants provide important information on the shape of the emission source in femtoscopy. For the simple case of noninteracting identical particles, we show how the fourth-order source cumulant can be determined from measured cumulants in momentum space. The textbook Gram-Charlier s......Lowest-order cumulants provide important information on the shape of the emission source in femtoscopy. For the simple case of noninteracting identical particles, we show how the fourth-order source cumulant can be determined from measured cumulants in momentum space. The textbook Gram...

  6. Evaluating Cumulative Ecosystem Response to Restoration Projects in the Columbia River Estuary, Annual Report 2004

    Energy Technology Data Exchange (ETDEWEB)

    Diefenderfer, Heida L.; Roegner, Curtis; Thom, Ronald M.; Dawley, Earl M.; Whiting, Allan H.; Johnson, Gary E.; Sobocinski, Kathryn L.; Anderson, Michael G.; Ebberts, Blaine


    The restoration of wetland salmon habitat in the tidal portion of the Columbia River is occurring at an accelerating pace and is anticipated to improve habitat quality and effect hydrological reconnection between existing and restored habitats. Currently multiple groups are applying a variety of restoration strategies in an attempt to emulate historic estuarine processes. However, the region lacks both a standardized means of evaluating the effectiveness of individual projects as well as methods for determining the cumulative effects of all restoration projects on a regional scale. This project is working to establish a framework to evaluate individual and cumulative ecosystem responses to restoration activities in order to validate the effectiveness of habitat restoration activities designed to benefit salmon through improvements to habitat quality and habitat opportunity (i.e. access) in the Columbia River from Bonneville Dam to the ocean. The review and synthesis of approaches to measure the cumulative effects of multiple restoration projects focused on defining methods and metrics of relevance to the CRE, and, in particular, juvenile salmon use of this system. An extensive literature review found no previous study assessing the cumulative effects of multiple restoration projects on the fundamental processes and functions of a large estuarine system, although studies are underway in other large land-margin ecosystems including the Florida Everglades and the Louisiana coastal wetlands. Literature from a variety of scientific disciplines was consulted to identify the ways that effects can accumulate (e.g., delayed effects, cross-boundary effects, compounding effects, indirect effects, triggers and thresholds) as well as standard and innovative tools and methods utilized in cumulative effects analyses: conceptual models, matrices, checklists, modeling, trends analysis, geographic information systems, carrying capacity analysis, and ecosystem analysis. Potential

  7. Evaluation of the HF-Radar network system around Taiwan using normalized cumulative Lagrangian separation. (United States)

    Fredj, Erick; Kohut, Josh; Roarty, Hugh; Lai, Jian-Wu


    The Lagrangian separation distance between the endpoints of simulated and observed drifter trajectories is often used to assess the performance of numerical particle trajectory models. However, the separation distance fails to indicate relative model performance in weak and strong current regions, such as over continental shelves and the adjacent deep ocean. A skill score described in detail by (Lui 2011) was applied to estimate the cumulative Lagrangian separation distances normalized by the associated cumulative trajectory lengths. In contrast, the Lagrangian separation distance alone gives a misleading result. The proposed dimensionless skill score is particularly useful when the number of drifter trajectories is limited and neither a conventional Eulerian-based velocity nor a Lagrangian based probability density function may be estimated. The skill score assesses The Taiwan Ocean Radar Observing System (TOROS) performance. TOROS consists of 17 SeaSonde type radars around the Taiwan Island. The currents off Taiwan are significantly influenced by the nearby Kuroshio current. The main stream of the Kuroshio flows along the east coast of Taiwan to the north throughout the year. Sometimes its branch current also bypasses the south end of Taiwan and goes north along the west coast of Taiwan. The Kuroshio is also prone to seasonal change in its speed of flow, current capacity, distribution width, and depth. The evaluations of HF-Radar National Taiwanese network performance using Lagrangian drifter records demonstrated the high quality and robustness of TOROS HF-Radar data using a purely trajectory-based non-dimensional index. Yonggang Liu and Robert H. Weisberg, "Evaluation of trajectory modeling in different dynamic regions using normalized cumulative Lagrangian separation", Journal of Geophysical Research, Vol. 116, C09013, doi:10.1029/2010JC006837, 2011

  8. Cumulative biological impacts framework for solar energy projects in the California Desert (United States)

    Davis, Frank W.; Kreitler, Jason R.; Soong, Oliver; Stoms, David M.; Dashiell, Stephanie; Hannah, Lee; Wilkinson, Whitney; Dingman, John


    This project developed analytical approaches, tools and geospatial data to support conservation planning for renewable energy development in the California deserts. Research focused on geographical analysis to avoid, minimize and mitigate the cumulative biological effects of utility-scale solar energy development. A hierarchical logic model was created to map the compatibility of new solar energy projects with current biological conservation values. The research indicated that the extent of compatible areas is much greater than the estimated land area required to achieve 2040 greenhouse gas reduction goals. Species distribution models were produced for 65 animal and plant species that were of potential conservation significance to the Desert Renewable Energy Conservation Plan process. These models mapped historical and projected future habitat suitability using 270 meter resolution climate grids. The results were integrated into analytical frameworks to locate potential sites for offsetting project impacts and evaluating the cumulative effects of multiple solar energy projects. Examples applying these frameworks in the Western Mojave Desert ecoregion show the potential of these publicly-available tools to assist regional planning efforts. Results also highlight the necessity to explicitly consider projected land use change and climate change when prioritizing areas for conservation and mitigation offsets. Project data, software and model results are all available online.

  9. Cumulative Effects of Coastal Habitat Alterations on Fishery Resources: toward Prediction at Regional Scales

    Directory of Open Access Journals (Sweden)

    Stephen J. Jordan


    Full Text Available Coastal habitat alterations such as the loss of submersed aquatic vegetation (SAV and hardening of shorelines could have cumulative effects on valuable fishery resources. To investigate this effect, we developed a multiscale modeling framework for blue crab (Callinectes sapidus in the northern Gulf of Mexico. Areal coverage of shoreline land cover and SAV for Mobile Bay, Alabama, were combined with information from small-scale biological studies and long-term, large-scale commercial fishery data to model the potential effects of marginal habitat losses on the blue crab fishery. We applied stochastic variation in annual recruitment to the fishery to estimate probabilities for sustainable harvests under scenarios of habitat loss. The simulations suggested that, accumulated over large areas, relatively small local losses of estuarine marsh edge and SAV habitats could have long-term negative effects on the sustainability of the fishery. Spatially extensive models are required to investigate the cumulative ecological effects of many local environmental changes. The requisite scaling adds uncertainty and reduces precision, but if model parameters are accurate at each scale, accurate predictions of long-term outcomes and probabilities are possible.

  10. Social organization and the evolution of cumulative technology in apes and hominins. (United States)

    Pradhan, Gauri R; Tennie, Claudio; van Schaik, Carel P


    Culturally supported accumulation (or ratcheting) of technological complexity is widely seen as characterizing hominin technology relative to that of the extant great apes, and thus as representing a threshold in cultural evolution. To explain this divide, we modeled the process of cultural accumulation of technology, which we defined as adding new actions to existing ones to create new functional combinations, based on a model for great ape tool use. The model shows that intraspecific and interspecific variation in the presence of simple and cumulative technology among extant orangutans and chimpanzees is largely due to variation in sociability, and hence opportunities for social learning. The model also suggests that the adoption of extensive allomaternal care (cooperative breeding) in early Pleistocene Homo, which led to an increase in sociability and to teaching, and hence increased efficiency of social learning, was enough to facilitate technological ratcheting. Hence, socioecological changes, rather than advances in cognitive abilities, can account for the cumulative cultural changes seen until the origin of the Acheulean. The consequent increase in the reliance on technology could have served as the pacemaker for increased cognitive abilities. Our results also suggest that a more important watershed in cultural evolution was the rise of donated culture (technology or concepts), in which technology or concepts was transferred to naïve individuals, allowing them to skip many learning steps, and specialization arose, which allowed individuals to learn only a subset of the population's skills. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Cumulative Contextual Risk and Behavior Problems among Children with Substance Using Mothers: The Mediating Role of Mothers? and Children?s Coping Strategies


    Zhang, Jing; Slesnick, Natasha


    Substance using mothers vary in their exposure to an accumulation of contextual risks associated with their drug-using life styles, likely leading to variability in their children?s behavioral outcomes. The present study examined a mediation model interrelating mothers? cumulative risk exposure, children?s behavior problems, and coping strategies of both mothers and children. Findings showed that mothers? greater exposure to cumulative risk was associated with lower utilization of task-orient...


    Directory of Open Access Journals (Sweden)

    Trenca Ioan


    Full Text Available One of the positive effects of the financial crises is the increasing concern of the supervisors regarding the financial system’s stability. There is a need to strengthen the links between different financial components of the financial system and the macroeconomic environment. Banking systems that have an adequate capitalization and liquidity level may face easier economic and financial shocks. The purpose of this empirical study is to identify the main determinants of the banking system’s stability and soundness in the Central and Eastern Europe countries. We asses the impact of different macroeconomic variables on the quality of capital and liquidity conditions and examine the behaviour of these financial stability indicators, by analyzing a sample of 10 banking systems during 2000-2011. The availability of banking capital signals the banking system’s resiliency to shocks. Capital adequacy ratio is the main indicator used to assess the banking fragility. One of the causes of the 2008-2009 financial crisis was the lack of liquidity in the banking system which led to the collapse of several banking institutions and macroeconomic imbalances. Given the importance of liquidity for the banking system, we propose several models in order to determine the macroeconomic variables that have a significant influence on the liquid reserves to total assets ratio. We found evidence that GDP growth, inflation, domestic credit to private sector, as well as the money and quasi money aggregate indicator have significant impact on the banking stability. The empirical regression confirms the high level of interdependence of the real sector with the financial-banking sector. Also, they prove the necessity for an effective macro prudential supervision at country level which enables the supervisory authorities to have an adequate control over the macro prudential indicators and to take appropriate decisions at the right time.

  13. Evidence that non-dreamers do dream: a REM sleep behaviour disorder model. (United States)

    Herlin, Bastien; Leu-Semenescu, Smaranda; Chaumereuil, Charlotte; Arnulf, Isabelle


    To determine whether non-dreamers do not produce dreams or do not recall them, subjects were identified with no dream recall with dreamlike behaviours during rapid eye movement sleep behaviour disorder, which is typically characterised by dream-enacting behaviours congruent with sleep mentation. All consecutive patients with idiopathic rapid eye movement sleep behaviour disorder or rapid eye movement sleep behaviour disorder associated with Parkinson's disease who underwent a video-polysomnography were interviewed regarding the presence or absence of dream recall, retrospectively or upon spontaneous arousals. The patients with no dream recall for at least 10 years, and never-ever recallers were compared with dream recallers with rapid eye movement sleep behaviour disorder regarding their clinical, cognitive and sleep features. Of the 289 patients with rapid eye movement sleep behaviour disorder, eight (2.8%) patients had no dream recall, including four (1.4%) patients who had never ever recalled dreams, and four patients who had no dream recall for 10-56 years. All non-recallers exhibited, daily or almost nightly, several complex, scenic and dreamlike behaviours and speeches, which were also observed during rapid eye movement sleep on video-polysomnography (arguing, fighting and speaking). They did not recall a dream following sudden awakenings from rapid eye movement sleep. These eight non-recallers with rapid eye movement sleep behaviour disorder did not differ in terms of cognition, clinical, treatment or sleep measures from the 17 dreamers with rapid eye movement sleep behaviour disorder matched for age, sex and disease. The scenic dreamlike behaviours reported and observed during rapid eye movement sleep in the rare non-recallers with rapid eye movement sleep behaviour disorder (even in the never-ever recallers) provide strong evidence that non-recallers produce dreams, but do not recall them. Rapid eye movement sleep behaviour disorder provides a new model to

  14. Evidence for the Magnetic Breakout Model in AN Equatorial Coronal-Hole Jet (United States)

    Kumar, P.; Karpen, J.; Antiochos, S. K.; Wyper, P. F.; DeVore, C. R.; DeForest, C. E.


    We analyzed an equatorial coronal-hole jet observed by Solar Dynamic Observatory (SDO)/AtmosphericImaging Assembly (AIA). The source-region magnetic field structure is consistent withthe embedded-bipole topology that we identified and modeled previously as a source of coronal jets. Theinitial brightening was observed below a sigmoid structure about 25 min before the onset of an untwisting jet.A circular magnetic flux rope with a mini-filament rose slowly at the speed of ˜15 km/s , then accelerated(˜126 km/s) during the onset of explosive breakout reconnection. Multiple plasmoids, propagating upward(˜135 km/s) and downward (˜55 km/s ), were detected behind the rising flux rope shortly before andduring explosive breakout reconnection. The jet was triggered when the rising flux rope interacted with theoverlying magnetic structures near the outer spine. This event shows a clear evidence of reconnection not onlybelow the flux rope but also a breakout reconnection above the flux rope. During the breakout reconnection,we observed heating of the flux rope, deflection of loops near the spine, and formation of multiple ribbons.The explosive breakout reconnection destroyed the flux rope that produced an untwisting jet with a speed of˜380 km/s . HMI magnetograms reveal the shear motion at theeruption site, but do not show any significant flux emergence or cancellation during or 2 hours before theeruption. Therefore, the free energy powering this jet most likely originated in magnetic shear concentratedat the polarity inversion line within the embedded bipole-a mini-filament channel-possibly created by helicitycondensation. The result of of a statistical study of multiple jets will also be discussed.

  15. An application of a modified experiential learning model for a higher education course: Evidence of increased outcomes


    Roark, Mark F.; Norling, Jonathan C.


    This case study applied a modified Experiential Learning Theory (ELT) model in an undergraduate outdoor recreation management course. The Kolb (1984) ELT model was modified to accommodate the higher education learning processes suggested by L. B. Sharp (1943), Sugarman (1985) and Greenaway (1995). Results indicate evidence of increased student learning. Quantitative results from a retrospective pre/posttest evaluation of change score means in learning outcomes supported the study hypotheses t...

  16. Informed design of educational technology for teaching and learning? Towards an evidence-informed model of good practice


    Price, Linda; Kirkwood, Adrian


    The aim of this paper is to model evidence-informed design based on a selective critical analysis of research articles. We draw upon findings from an investigation into practitioners’ use of educational technologies to synthesise and model what informs their designs. We found that practitioners’ designs were often driven by implicit assumptions about learning. These shaped both the design of interventions and the methods sought to derive evaluations and interpret the findings. We argue that i...

  17. Chlorine gas inhalation: human clinical evidence of toxicity and experience in animal models. (United States)

    White, Carl W; Martin, James G


    inhalation have demonstrated evidence of oxidative injury and inflammation. Early epithelial injury, airways hyperresponsiveness, and airway remodeling, likely diminishing over time, have been shown. As in humans, ALI/ARDS can occur, becoming more likely when the upper airways are bypassed. Inhalation models of chlorine toxicity provide unique opportunities for testing potential pharmacologic rescue agents.

  18. Using the Dynamic Model to develop an evidence-based and theory-driven approach to school improvement

    NARCIS (Netherlands)

    Creemers, B.P.M.; Kyriakides, L.


    This paper refers to a dynamic perspective of educational effectiveness and improvement stressing the importance of using an evidence-based and theory-driven approach. Specifically, an approach to school improvement based on the dynamic model of educational effectiveness is offered. The recommended

  19. Translating Evidence-Based Practice into a Comprehensive Educational Model within an Autism-Specific Special School (United States)

    Lambert-Lee, Katy A.; Jones, Rebecca; O'Sullivan, Julie; Hastings, Richard P.; Douglas-Cobane, Emma; Thomas J., Esther; Hughes, Carl; Griffith, Gemma


    Research evaluations of Applied Behaviour Analysis (ABA)-based interventions for children with autism demonstrate positive outcomes. However, little research has focused on the translation of these evidence-based interventions into service delivery models within existing education systems. In the present article, we provide a description of the…

  20. Measurement of multi-particle azimuthal correlations with the subevent cumulant method with the ATLAS detector

    CERN Document Server

    Zhou, Mingliang; The ATLAS collaboration


    The measurement of four-particle cumulant and anisotropic elliptic flow coefficient for the second harmonic, $c_{2}\\{4\\}$ and $v_{2}\\{4\\}$, are presented using $pp$ data at $\\sqrt{s}=5.02$ and $\\sqrt{s}=13$ TeV, and $p+$Pb data at $\\sqrt{s_{\\text{NN}}}=5.02$ TeV. These measurements aim to assess collective nature of multi-particle production. While collectivity is well established in $p$+Pb and Pb+Pb collisions, because of larger non-flow contributions, its evidence in $pp$ collisions is contested. The values of $c_{2}\\{4\\}$ are calculated using the standard cumulant method and recently proposed two and three subevent methods, which can further suppress the non-flow contributions in small systems. In these collisions systems, the three subevent method gives a negative $c_{2}\\{4\\}$, and thus a well-defined $v_{2}\\{4\\}$. The magnitude of $c_{2}\\{4\\}$ is found to be nearly independent of $\\langle N_{\\text{ch}} \\rangle$ and third harmonic $c_{3}\\{4\\}$ is consistent with 0. $v_{2}\\{4\\}$ is found to be smaller than...

  1. Framework tool for a rapid cumulative effects assessment: case of a prominent wetland in Myanmar. (United States)

    Pradhan, N; Habib, H; Venkatappa, M; Ebbers, T; Duboz, R; Shipin, O


    The wetland of focus, Inle Lake, located in central Myanmar, is well known for its unique biodiversity and culture, as well as for ingenious floating garden agriculture. During the last decades, the lake area has seen extensive degradation in terms of water quality, erosion, deforestation, and biodiversity concomitant with a major shift to unsustainable land use. The study was conducted, with an emphasis on water quality, to analyze environmental impacts (effects) changing the ecosystem and to comprehensively evaluate the environmental state of the ecosystem through an innovative Rapid Cumulative Effects Assessment framework tool. The assessment started with a framework-forming Participatory Rural Appraisal (PRA), which quantified and prioritized impacts over space and time. Critically important impacts were assessed for "intra-inter interactions" using the loop analysis simulation. Water samples were analyzed while geographic information system (GIS) and remote sensing were used to identify water pollution hotspots. It was concluded that out of a plethora of impacts, pollution from municipal sources, sedimentation, and effects exerted by floating gardens had the most detrimental impacts, which cumulatively affected the entire ecosystem. The framework tool was designed in a broad sense with a reference to highly needed assessments of poorly studied wetlands where degradation is evident, but scarcely quantified, and where long-term field studies are fraught with security issues and resource unavailability (post-conflict, poor and remote regions, e.g., Afghanistan, Laos, Sudan, etc.).

  2. Evidence for Ancestral Programming of Resilience in a Two-Hit Stress Model

    Directory of Open Access Journals (Sweden)

    Jamshid Faraji


    Full Text Available In a continuously stressful environment, the effects of recurrent prenatal stress (PS may accumulate across generations and alter stress vulnerability and resilience. Here, we report in female rats that a family history of recurrent ancestral PS facilitates certain aspects of movement performance, and that these benefits are abolished by the experience of a second hit, induced by a silent ischemia during adulthood. Female F4-generation rats with and without a family history of cumulative multigenerational PS (MPS were tested for skilled motor function before and after the induction of a minor ischemic insult by endothelin-1 infusion into the primary motor cortex. MPS resulted in improved skilled motor abilities and blunted hypothalamic-pituitary-adrenal (HPA axis function compared to non-stressed rats. Deep sequencing revealed downregulation of miR-708 in MPS rats along with upregulation of its predicted target genes Mapk10 and Rasd2. Through miR-708 stress may regulate mitogen-activated protein kinase (MAPK pathway activity. Hair trace elemental analysis revealed an increased Na/K ratio, which suggests a chronic shift in adrenal gland function. The ischemic lesion activated the HPA axis in MPS rats only; the lesion, however, abolished the advantage of MPS in skilled reaching. The findings indicate that MPS generates adaptive flexibility in movement, which is challenged by a second stressor, such as a neuropathological condition. Thus, a second “hit” by a stressor may limit behavioral flexibility and neural plasticity associated with ancestral stress.

  3. Role of sulfite additives in wine induced asthma: single dose and cumulative dose studies. (United States)

    Vally, H; Thompson, P J


    Wine appears to be a significant trigger for asthma. Although sulfite additives have been implicated as a major cause of wine induced asthma, direct evidence is limited. Two studies were undertaken to assess sulfite reactivity in wine sensitive asthmatics. The first study assessed sensitivity to sulfites in wine using a single dose sulfited wine challenge protocol followed by a double blind, placebo controlled challenge. In the second study a cumulative dose sulfited wine challenge protocol was employed to establish if wine sensitive asthmatics as a group have an increased sensitivity to sulfites. In study 1, 24 asthmatic patients with a strong history of wine induced asthma were screened. Subjects showing positive responses to single blind high sulfite (300 ppm) wine challenge were rechallenged on separate days in a double blind, placebo controlled fashion with wines of varying sulfite levels to characterise their responses to these drinks. In study 2, wine sensitive asthmatic patients (n=12) and control asthmatics (n=6) were challenged cumulatively with wine containing increasing concentrations of sulfite in order to characterise further their sensitivity to sulfites in wine. Four of the 24 self-reporting wine sensitive asthmatic patients were found to respond to sulfite additives in wine when challenged in a single dose fashion (study 1). In the double blind dose-response study all four had a significant fall in forced expiratory volume in one second (FEV(1)) (>15% from baseline) following exposure to wine containing 300 ppm sulfite, but did not respond to wines containing 20, 75 or 150 ppm sulfite. Responses were maximal at 5 minutes (mean (SD) maximal decline in FEV(1) 28.7 (13)%) and took 15-60 minutes to return to baseline levels. In the cumulative dose-response study (study 2) no significant difference was observed in any of the lung function parameters measured (FEV(1), peak expiratory flow (PEF), mid phase forced expiratory flow (FEF(25-75))) between wine

  4. Formulaic language in cortical and subcortical disease: Evidence of the dual process model.

    Directory of Open Access Journals (Sweden)

    Kelly Bridges


    Full Text Available Introduction: It is known that an intact cortical left hemisphere is crucial for language production. Recently, more credit is given to the right hemisphere and subcortical areas in the production of non-novel language, including formulaic language. John Hughlings Jackson (1874/1958, first described how propositional and non-propositional speech are differentially affected by neural impairment. Non-propositional language is often preserved following left hemisphere stroke even when aphasia is present (Code, 1982; Sidtis et al., 2009; Van Lancker Sidtis & Postman, 2006. With right hemisphere and subcortical stroke, formulaic language is reduced (Sidtis et al., 2009; Van Lancker Sidtis & Postman, 2006; Speedie et al., 1993. The dual process model of language competence states that propositional and non-propositional speech are processed differently in the brain, with novel speech controlled by the left hemisphere, and a right hemisphere/subcortical circuit modulating formulaic language (Van Lancker Sidtis, 2004; 2012. Two studies of formulaic language will be presented as further evidence of the dual process model: a study of formulaic language in Alzheimer’s disease, and a study of recited speech in Parkinson’s disease. Formulaic language includes overlearned words, phrases or longer linguistic units that are known to the native speaker, occur naturally in discourse, and are important for normal social interaction (Fillmore, 1979; Pawley & Syder, 1983; Van Lancker, 1988; Van Lancker Sidtis, 2004; Wray, 2002. Formulaic expressions include conversational speech formulas, idioms, proverbs, expletives, pause fillers, discourse elements, and sentence stems (stereotyped sentence-initials. Longer units of linguistic material, such as prayers, rhymes, and poems, termed recited speech, is another subtype of formulaic language that is learned in childhood and recited periodically throughout life. Cortical disease: Alzheimer’s disease and formulaic

  5. Cumulative risk hypothesis: Predicting and preventing child maltreatment recidivism. (United States)

    Solomon, David; Åsberg, Kia; Peer, Samuel; Prince, Gwendolyn


    Although Child Protective Services (CPS) and other child welfare agencies aim to prevent further maltreatment in cases of child abuse and neglect, recidivism is common. Having a better understanding of recidivism predictors could aid in preventing additional instances of maltreatment. A previous study identified two CPS interventions that predicted recidivism: psychotherapy for the parent, which was related to a reduced risk of recidivism, and temporary removal of the child from the parent's custody, which was related to an increased recidivism risk. However, counter to expectations, this previous study did not identify any other specific risk factors related to maltreatment recidivism. For the current study, it was hypothesized that (a) cumulative risk (i.e., the total number of risk factors) would significantly predict maltreatment recidivism above and beyond intervention variables in a sample of CPS case files and that (b) therapy for the parent would be related to a reduced likelihood of recidivism. Because it was believed that the relation between temporary removal of a child from the parent's custody and maltreatment recidivism is explained by cumulative risk, the study also hypothesized that that the relation between temporary removal of the child from the parent's custody and recidivism would be mediated by cumulative risk. After performing a hierarchical logistic regression analysis, the first two hypotheses were supported, and an additional predictor, psychotherapy for the child, also was related to reduced chances of recidivism. However, Hypothesis 3 was not supported, as risk did not significantly mediate the relation between temporary removal and recidivism. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Science and societal partnerships to address cumulative impacts

    Directory of Open Access Journals (Sweden)

    Carolyn J Lundquist


    Full Text Available Funding and priorities for ocean research are not separate from the underlying sociological, economic, and political landscapes that determine values attributed to ecological systems. Here we present a variation on science prioritisation exercises, focussing on inter-disciplinary research questions with the objective of shifting broad scale management practices to better address cumulative impacts and multiple users. Marine scientists in New Zealand from a broad range of scientific and social-scientific backgrounds ranked 48 statements of research priorities. At a follow up workshop, participants discussed five over-arching themes based on survey results. These themes were used to develop mechanisms to increase the relevance and efficiency of scientific research while acknowledging socio-economic and political drivers of research agendas in New Zealand’s ocean ecosystems. Overarching messages included the need to: 1 determine the conditions under which ‘surprises’ (sudden and substantive undesirable changes are likely to occur and the socio-ecological implications of such changes; 2 develop methodologies to reveal the complex and cumulative effects of change in marine systems, and their implications for resource use, stewardship, and restoration; 3 assess potential solutions to management issues that balance long-term and short-term benefits and encompass societal engagement in decision-making; 4 establish effective and appropriately resourced institutional networks to foster collaborative, solution-focused marine science; and 5 establish cross-disciplinary dialogues to translate diverse scientific and social-scientific knowledge into innovative regulatory, social and economic practice. In the face of multiple uses and cumulative stressors, ocean management frameworks must be adapted to build a collaborative framework across science, governance and society that can help stakeholders navigate uncertainties and socio-ecological surprises.

  7. Uncertainty analysis technique of dynamic response and cumulative damage properties of piping system

    International Nuclear Information System (INIS)

    Suzuki, Kohei; Aoki, Shigeru; Hara, Fumio; Hanaoka, Masaaki; Yamashita, Tadashi.


    It is a technologically important subject to establish the method of uncertainty analysis statistically examining the variation of the earthquake response and damage properties of equipment and piping system due to the change of input load and the parameters of structural system, for evaluating the aseismatic capability and dynamic structural reliability of these systems. The uncertainty in the response and damage properties when equipment and piping system are subjected to excessive vibration load is mainly dependent on the irregularity of acting input load such as the unsteady vibration of earthquakes, and structural uncertainty in forms and dimensions. This study is the basic one to establish the method for evaluating the uncertainty in the cumulative damage property at the time of resonant vibration of piping system due to the disperse of structural parameters with a simple model. First, the piping models with simple form were broken by resonant vibration, and the uncertainty in the cumulative damage property was evaluated. Next, the response analysis using an elasto-plastic mechanics model was performed by numerical simulation. Finally, the method of uncertainty analysis for response and damage properties by the perturbation method utilizing equivalent linearization was proposed, and its propriety was proved. (Kako, I.)

  8. Cumulative Radiative Forcing Implications of Deployment Strategies for Carbon Capture and Storage (United States)

    Sathre, R. C.; Masanet, E.


    Carbon capture and storage (CCS) is increasingly discussed as a potential means of mitigating the climate disruption associated with fossil fuel use. Some technologies for capturing, transporting, and sequestering carbon dioxide (CO2) are already mature, while others technologies under development may lead to more cost- and energy-efficient CCS systems. Various elements of CCS systems are currently in operation at relatively small scale, but will need to be scaled up very substantially in order to make a significant contribution to climate change mitigation. Because the rate of fossil fuel CO2 emission is continuing to increase and the emitted CO2 will remain in the atmosphere for long time periods, the speed at which CCS is deployed will strongly affect the cumulative CO2 emission and the climate impacts. To better understand these issues, in this analysis we integrate scenario forecasting of energy supply systems, life cycle emission modeling, and time-dependent calculations of cumulative radiative forcing. We develop a series of CCS deployment scenarios that describe plausible future trajectories for CCS implementation in the US electric power plant fleet. The scenarios incorporate dimensions such as speed of deployment build-out, year of initiating deployment, efficiency of capture technology, and installation in new power plants vs. retrofitting existing plants. We conduct life cycle greenhouse gas (GHG) emissions analyses of each scenario to estimate annual emission profiles of CO2, CH4, and N2O over a 90-year time horizon, from 2010 to 2100. We then model the atmospheric dynamics of the emitted GHGs including atmospheric decay and instantaneous radiative forcing patterns over time. Finally, we determine the cumulative radiative forcing of each scenario, which we use as a proxy for surface temperature change and resulting disruption to physical, ecological and social systems. The results show strong climate mitigation benefits of early, aggressive

  9. Cumulative effects of repeated subthreshold doses of ultraviolet radiation

    International Nuclear Information System (INIS)

    Parrish, J.A.; Zaynoun, S.; Anderson, R.R.


    For fair Caucasian skin, the minimal delayed erythema dose (MED) 24 hr after exposure to broadband UVA is about 1200 times greater than the MED of broadband UVB, for both single and multiple daily exposures. Repeated daily exposure to doses less than MED results in cumulative effects manifest by gradual lowering of the daily dose threshold for delayed erythema and pigmentation induced by UVA or UVB. At threshold doses, UVB is more erythemogenic than melanogenic; the opposite is true for UVA. Repeated daily UVA exposure greatly enhances melanogenesis such that markedly suberythemogenic exposure doses of UVA result in true melanogenesis

  10. Exact probability distribution function for the volatility of cumulative production (United States)

    Zadourian, Rubina; Klümper, Andreas


    In this paper we study the volatility and its probability distribution function for the cumulative production based on the experience curve hypothesis. This work presents a generalization of the study of volatility in Lafond et al. (2017), which addressed the effects of normally distributed noise in the production process. Due to its wide applicability in industrial and technological activities we present here the mathematical foundation for an arbitrary distribution function of the process, which we expect will pave the future research on forecasting of the production process.

  11. Computation of current cumulants for small nonequilibrium systems

    Czech Academy of Sciences Publication Activity Database

    Baiesi, M.; Maes, C.; Netočný, Karel


    Roč. 135, č. 1 (2009), s. 57-75 ISSN 0022-4715 R&D Projects: GA ČR GC202/07/J051 Institutional research plan: CEZ:AV0Z10100520 Keywords : fluctuations * nonequilibrium * cumulant expansion Subject RIV: BE - Theoretical Physics Impact factor: 1.390, year: 2009π=2

  12. Confidence bounds on an empirical cumulative distribution function

    International Nuclear Information System (INIS)

    Andres, T.H.


    Methods are developed for using data from an empirical cumulative distribution function (CDF) to generate, at each point in the range of the data an upper confidence bound on the estimated value of the underlying CDF. Applications are demonstrated where a confidence bound is applied to the empirical distribution of maximum effective annual dose equivalent obtained from a set of Monte Carlo simulations in an environmental assessment of nuclear fuel waste disposal. This bound can then be used to compare the empirical dose CDF with possible regulatory guidelines for dose from a disposal facility. Methods presented in the report can be used to select the number of simulations needed to meet such guidelines

  13. The Influence of Weight-of-Evidence Messages on (Vaccine) Attitudes: A Sequential Mediation Model. (United States)

    Clarke, Christopher E; Weberling McKeever, Brooke; Holton, Avery; Dixon, Graham N


    Media coverage of contentious risk issues often features competing claims about whether a risk exists and what scientific evidence shows, and journalists often cover these issues by presenting both sides. However, for topics defined by scientific agreement, balanced coverage erroneously heightens uncertainty about scientific information and the issue itself. In this article, we extend research on combating so-called information and issue uncertainty using weight of evidence, drawing on the discredited autism-vaccine link as a case study. We examine whether people's perceptions of issue uncertainty (about whether a link exists) change before and after they encounter a news message with weight-of-evidence information. We also explore whether message exposure is associated with broader issue judgments, specifically vaccine attitudes. Participants (n = 181) read news articles that included or omitted weight-of-evidence content stating that scientific studies have found no link and that scientists agree that none exists. Postexposure issue uncertainty decreased-in other words, issue certainty increased-from preexposure levels across all conditions. Moreover, weight-of-evidence messages were associated with positive vaccine attitudes indirectly via reduced information uncertainty (i.e., one's belief that scientific opinion and evidence concerning a potential link is unclear) as well as issue uncertainty. We discuss implications for risk communication.

  14. Cumulative Repetition Effects across Multiple Readings of a Word: Evidence from Eye Movements (United States)

    Kamienkowski, Juan E.; Carbajal, M. Julia; Bianchi, Bruno; Sigman, Mariano; Shalom, Diego E.


    When a word is read more than once, reading time generally decreases in the successive occurrences. This Repetition Effect has been used to study word encoding and memory processes in a variety of experimental measures. We studied naturally occurring repetitions of words within normal texts (stories of around 3,000 words). Using linear mixed…

  15. No evidence for cumulative effects in a Dnmt3b hypomorph across multiple generations

    Czech Academy of Sciences Publication Activity Database

    Youngson, N.A.; Epp, Trevor; Roberts, A.R.; Daxinger, L.; Ashe, A.; Huang, E.; Lester, K.L.; Harten, S.K.; Kay, G.F.; Cox, T.; Matthews, J.M.; Chong, S.; Whitelaw, E.


    Roč. 24, 5-6 (2013), s. 206-217 ISSN 0938-8990 Institutional support: RVO:68378050 Keywords : epigenetic inheritance * mammalian development * transgenerational Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.883, year: 2013

  16. Cumulative Risk, Teacher Well-Being and Instructional Quality: Evidence from the DRC and Ghana (United States)

    Wolf, Sharon


    There is growing concern that teachers in low-income countries are increasingly demotivated, which may partially explain deteriorating teaching performance and student learning outcomes, high rates of turnover and absenteeism, and misconduct. At the same time, remarkably little systematic research has examined the living and working conditions for…

  17. The functional origin of dinosaur bipedalism: Cumulative evidence from bipedally inclined reptiles and disinclined mammals. (United States)

    Persons, W Scott; Currie, Philip J


    Bipedalism is a trait basal to, and widespread among, dinosaurs. It has been previously argued that bipedalism arose in the ancestors of dinosaurs for the function of freeing the forelimbs to serve as predatory weapons. However, this argument does not explain why bipedalism was retained among numerous herbivorous groups of dinosaurs. We argue that bipedalism arose in the dinosaur line for the purpose of enhanced cursoriality. Modern facultatively bipedal lizards offer an analog for the first stages in the evolution of dinosaurian bipedalism. Many extant lizards assume a bipedal stance while attempting to flee predators at maximum speed. Bipedalism, when combined with a caudofemoralis musculature, has cursorial advantages because the caudofemoralis provides a greater source of propulsion to the hindlimbs than is generally available to the forelimbs. That cursorial advantage explains the relative abundance of cursorial facultative bipeds and obligate bipeds among fossil diapsids and the relative scarcity of either among mammals. Having lost their caudofemoralis in the Permian, perhaps in the context of adapting to a fossorial lifestyle, the mammalian line has been disinclined towards bipedalism, but, having never lost the caudofemoralis of their ancestors, cursorial avemetatarsalians (bird-line archosaurs) were naturally inclined towards bipedalism. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. The more you play, the more aggressive you become: A long-term experimental study of cumulative violent video game effects on hostile expectations and aggressive behavior

    NARCIS (Netherlands)

    Hasan, Y.; Bègue, L.; Scharkow, M.; Bushman, B.J.


    It is well established that violent video games increase aggression. There is a stronger evidence of short-term violent video game effects than of long-term effects. The present experiment tests the cumulative long-term effects of violent video games on hostile expectations and aggressive behavior

  19. Whither nursing models? The value of nursing theory in the context of evidence-based practice and multidisciplinary health care. (United States)

    McCrae, Niall


    This paper presents a discussion of the role of nursing models and theory in the modern clinical environment. Models of nursing have had limited success in bridging the gap between theory and practice. Literature on nursing models and theory since the 1950s, from health and social care databases. Arguments against nursing theory are challenged. In the current context of multidisciplinary services and the doctrine of evidence-based practice, a unique theoretical standpoint comprising the art and science of nursing is more relevant than ever. A theoretical framework should reflect the eclectic, pragmatic practice of nursing. Nurse educators and practitioners should embrace theory-based practice as well as evidence-based practice. © 2011 The Author. Journal of Advanced Nursing © 2011 Blackwell Publishing Ltd.

  20. The parasitic model of L2 and L3 vocabulary acquisition: evidence from naturalistic and experimental studies

    Directory of Open Access Journals (Sweden)

    Peter Ecke


    Full Text Available This paper reviews evidence for the Parasitic Model of Vocabulary Acquisition for second and third language learners/developing multilinguals. It first describes the model’s predictions about default processes based on the detection and use of similarity at the three stages involved in the development of individual lexical items: (1 the establishing of a form representation, (2 the building of connections to syntactic frame and concept representations, and (3 the strengthening and automatization of representations and access routes. The paper then summarizes both naturalistic and experimental evidence for processes involved at these three stages. Finally it discusses open issues and potential areas for future investigation.