WorldWideScience

Sample records for policy screening models

  1. Melanoma screening: Informing public health policy with quantitative modelling.

    Directory of Open Access Journals (Sweden)

    Stephen Gilmore

    1982 has resulted in greater diagnostic incidence and reduced mortality, but the reduced mortality carried a significant cost per life saved. I implement the model out to 2028 and demonstrate that the enhanced secondary prevention that began in 1982 becomes increasingly cost-effective over the period 2013-2028. On the other hand, I show that reductions in mortality achieved by significantly enhancing secondary prevention beyond 2013 levels are comparable with those achieved by only modest improvements in late-stage disease survival. Given the ballooning costs of increased melanoma surveillance, I suggest the process of public health policy decision-making-particularly with respect to the public funding of melanoma screening and discretionary mole removal-would be better served by incorporating the results of quantitative modelling.

  2. A Model Strategy and Policy for Screening Firefighter Candidates

    National Research Council Canada - National Science Library

    Pope, Christopher M

    2006-01-01

    ... and motivated by the desire to serve their community and country. Reasons for and evidence of the need for a new firefighter candidate screening strategy to support this new mission are addressed in this thesis...

  3. A Markov Decision Process Model for Cervical Cancer Screening Policies in Colombia.

    Science.gov (United States)

    Akhavan-Tabatabaei, Raha; Sánchez, Diana Marcela; Yeung, Thomas G

    2017-02-01

    Cervical cancer is the second most common cancer in women around the world, and the human papillomavirus (HPV) is universally known as the necessary agent for developing this disease. Through early detection of abnormal cells and HPV virus types, cervical cancer incidents can be reduced and disease progression prevented. We propose a finite-horizon Markov decision process model to determine the optimal screening policies for cervical cancer prevention. The optimal decision is given in terms of when and what type of screening test to be performed on a patient based on her current diagnosis, age, HPV contraction risk, and screening test results. The cost function considers the tradeoff between the cost of prevention and treatment procedures and the risk of taking no action while taking into account a cost assigned to loss of life quality in each state. We apply the model to data collected from a representative sample of 1141 affiliates at a health care provider located in Bogotá, Colombia. To track the disease incidence more effectively and avoid higher cancer rates and future costs, the optimal policies recommend more frequent colposcopies and Pap tests for women with riskier profiles.

  4. An evaluation of screening policies for cervical cancer in England and Wales using a computer simulation model.

    OpenAIRE

    Parkin, D M; Moss, S M

    1986-01-01

    Several screening policies have been recommended for implementation in England and Wales in the last 20 years, although no evidence as to their relative effectiveness or efficiency has been provided. Using a computer simulation model, the outcomes expected from those policies had they been implemented over a 30 year period (1961-90) have been examined. The original policies based on five-yearly testing of women aged over 35 appear to be the most cost-effective, and extension of screening to y...

  5. Cost-effectiveness of breast cancer screening policies using simulation.

    Science.gov (United States)

    Gocgun, Y; Banjevic, D; Taghipour, S; Montgomery, N; Harvey, B J; Jardine, A K S; Miller, A B

    2015-08-01

    In this paper, we study breast cancer screening policies using computer simulation. We developed a multi-state Markov model for breast cancer progression, considering both the screening and treatment stages of breast cancer. The parameters of our model were estimated through data from the Canadian National Breast Cancer Screening Study as well as data in the relevant literature. Using computer simulation, we evaluated various screening policies to study the impact of mammography screening for age-based subpopulations in Canada. We also performed sensitivity analysis to examine the impact of certain parameters on number of deaths and total costs. The analysis comparing screening policies reveals that a policy in which women belonging to the 40-49 age group are not screened, whereas those belonging to the 50-59 and 60-69 age groups are screened once every 5 years, outperforms others with respect to cost per life saved. Our analysis also indicates that increasing the screening frequencies for the 50-59 and 60-69 age groups decrease mortality, and that the average number of deaths generally decreases with an increase in screening frequency. We found that screening annually for all age groups is associated with the highest costs per life saved. Our analysis thus reveals that cost per life saved increases with an increase in screening frequency. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Using Collaborative Simulation Modeling to Develop a Web-Based Tool to Support Policy-Level Decision Making About Breast Cancer Screening Initiation Age

    Directory of Open Access Journals (Sweden)

    Elizabeth S. Burnside MD, MPH, MS

    2017-07-01

    Full Text Available Background: There are no publicly available tools designed specifically to assist policy makers to make informed decisions about the optimal ages of breast cancer screening initiation for different populations of US women. Objective: To use three established simulation models to develop a web-based tool called Mammo OUTPuT. Methods: The simulation models use the 1970 US birth cohort and common parameters for incidence, digital screening performance, and treatment effects. Outcomes include breast cancers diagnosed, breast cancer deaths averted, breast cancer mortality reduction, false-positive mammograms, benign biopsies, and overdiagnosis. The Mammo OUTPuT tool displays these outcomes for combinations of age at screening initiation (every year from 40 to 49, annual versus biennial interval, lifetime versus 10-year horizon, and breast density, compared to waiting to start biennial screening at age 50 and continuing to 74. The tool was piloted by decision makers (n = 16 who completed surveys. Results: The tool demonstrates that benefits in the 40s increase linearly with earlier initiation age, without a specific threshold age. Likewise, the harms of screening increase monotonically with earlier ages of initiation in the 40s. The tool also shows users how the balance of benefits and harms varies with breast density. Surveys revealed that 100% of users (16/16 liked the appearance of the site; 94% (15/16 found the tool helpful; and 94% (15/16 would recommend the tool to a colleague. Conclusions: This tool synthesizes a representative subset of the most current CISNET (Cancer Intervention and Surveillance Modeling Network simulation model outcomes to provide policy makers with quantitative data on the benefits and harms of screening women in the 40s. Ultimate decisions will depend on program goals, the population served, and informed judgments about the weight of benefits and harms.

  7. Evidence for the credibility of health economic models for health policy decision-making: a systematic literature review of screening for abdominal aortic aneurysms

    DEFF Research Database (Denmark)

    Søgaard, Rikke; Lindholt, Jes S.

    2012-01-01

    OBJECTIVE: To investigate whether the credibility of health economic models of screening for abdominal aortic aneurysms for health policy decision-making has improved since 2005 when a systematic review by Campbell et al. concluded that reporting standards were poor and there was divergence between...... benefited from general advances in health economic modelling and some improvements in reporting were noted. However, the low level of agreement between studies in model structures and assumptions, and difficulty in justifying these (convergent validity), remain a threat to the credibility of health economic...

  8. Public Preferences for Lung Cancer Screening Policies.

    Science.gov (United States)

    Broekhuizen, Henk; Groothuis-Oudshoorn, Catharina G M; Vliegenthart, Rozemarijn; Groen, Harry; IJzerman, Maarten J

    Because early detection of lung cancer can substantially improve survival, there is increasing attention for lung cancer screening. To estimate public preferences for lung cancer screening and to identify subgroups in preferences. Seven important attributes were selected using the literature, interviews, and a panel session. Preferences were elicited using a swing weighting questionnaire. The resulting attribute weights indicate the relative importance of swings from the worst to the best level between attributes. Hierarchical clustering was used to identify subgroups with different attribute weights. One thousand thirty-four respondents from a representative Dutch panel aged between 40 and 80 years were included. The identified attributes were location of screening (weight = 0.18 ± 0.16), mode of screening (weight = 0.17 ± 0.14), sensitivity (weight = 0.16 ± 0.13) and specificity (weight = 0.13 ± 0.12) of the screening modality, waiting time until results (weight = 0.13 ± 0.12), radiation burden (weight = 0.13 ± 0.12), and duration of screening procedure (weight = 0.10 ± 0.09). Most respondents preferred breath analysis (45%) to giving blood samples (31%) or going through a scanner (24%) as screening modality; 59% preferred screening at the general practitioner's office instead of at the hospital. There was a significant difference in education between the five identified preference subgroups (P screening. Different screening policies and implementation strategies may be appropriate for particular preference subgroups. Our results indicate that people prefer breath analysis and that they are more likely to attend screening modalities that can be used at a primary care facility. Copyright © 2017 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  9. Newborn bloodspot screening policy framework for Australia

    Directory of Open Access Journals (Sweden)

    Peter O'Leary

    2015-09-01

    Full Text Available Background The aim of newborn bloodspot screening (NBS is to identify rare genetic and non-genetic conditions in children soon after birth in order to commence therapies that prevent the development of progressive, serious, and irreversible disabilities. Universal NBS programmes have been implemented in most countries, with minor adaptations to target conditions most relevant to the local healthcare environment. Aims In this article, we describe the initiatives of international and Australian governments to develop policies to address the expansion of NBS in their healthcare systems. Methods We have reviewed published public policies and literature to formulate recommendations based on clinical, social, legal, and ethical principles to inform a national governance and policy framework for Australia. Results Australian policy makers have been slow to develop a coordinated plan. While the experience from other governments can guide our national policy, there are specific areas that require further consideration by Australian health experts. Key reforms involve the separation of policy and operational activities, multidisciplinary decision-making and oversight by the Australian Health Ministers’ Advisory Council for policy direction. Conclusion A formal national policy framework will guide the coordination of NBS services that can adapt to the needs of Australian children and families.

  10. Cost-effectiveness of cervical cancer screening: comparison of screening policies

    NARCIS (Netherlands)

    M.E. van den Akker-van Marle (Elske); M. van Ballegooijen (Marjolein); G.J. van Oortmarssen (Gerrit); R. Boer (Rob); J.D.F. Habbema (Dik)

    2002-01-01

    textabstractBACKGROUND: Recommended screening policies for cervical cancer differ widely among countries with respect to targeted age range, screening interval, and total number of scheduled screening examinations (i.e., Pap smears). We compared the efficiency of cervical

  11. Modeling environmental policy

    International Nuclear Information System (INIS)

    Martin, W.E.; McDonald, L.A.

    1997-01-01

    The eight book chapters demonstrate the link between the physical models of the environment and the policy analysis in support of policy making. Each chapter addresses an environmental policy issue using a quantitative modeling approach. The volume addresses three general areas of environmental policy - non-point source pollution in the agricultural sector, pollution generated in the extractive industries, and transboundary pollutants from burning fossil fuels. The book concludes by discussing the modeling efforts and the use of mathematical models in general. Chapters are entitled: modeling environmental policy: an introduction; modeling nonpoint source pollution in an integrated system (agri-ecological); modeling environmental and trade policy linkages: the case of EU and US agriculture; modeling ecosystem constraints in the Clean Water Act: a case study in Clearwater National Forest (subject to discharge from metal mining waste); costs and benefits of coke oven emission controls; modeling equilibria and risk under global environmental constraints (discussing energy and environmental interrelations); relative contribution of the enhanced greenhouse effect on the coastal changes in Louisiana; and the use of mathematical models in policy evaluations: comments. The paper on coke area emission controls has been abstracted separately for the IEA Coal Research CD-ROM

  12. Breast screening policy: Are we heading in the right direction?

    Energy Technology Data Exchange (ETDEWEB)

    Evans, A., E-mail: a.z.evans@dundee.ac.uk [Dundee Cancer Centre, Ninewells Hospital and Medical School, University of Dundee, Dundee (United Kingdom); Whelehan, P. [Dundee Cancer Centre, Ninewells Hospital and Medical School, University of Dundee, Dundee (United Kingdom)

    2011-10-15

    There is a large body of evidence supporting 2-yearly screening of women aged 50-69 years. There is good evidence for a mortality reduction from mammographic screening in women aged 40 to 49 years but a 1-year interval is required. The lack of specificity of screening in young women does remain a problem. There is no evidence to suggest that a single screen between the ages of 47 and 50 years within a programme screening at 3-year intervals will reduce mortality; the trials showing a mortality benefit in women in their 40s included multiple screening episodes and shorter screening intervals. There is no randomized, controlled trial evidence to support screening in women aged above 70 years and screening this age group will cause greater harm than in younger women through higher rates of over-diagnosis and consequent over-treatment. The randomized phase of the screening age extension, which at the moment is planned to last only 6 years, should not be immediately followed by general implementation of the policy. Only if and when additional mortality reductions and an acceptable balance between benefit and harms are shown to be achieved by the extra screens should the 2007 Cancer Reform Strategy policy on age extension be implemented. Resources saved by delaying or abandoning the roll-out of the age extension could potentially be redirected towards reducing the current 3 year screening interval to 2 years in women aged 50-69 years. However, reducing the screening interval to 2 years for women aged 50-69 years would require significantly more screening invitations and resources than the proposed age extension.

  13. Breast screening policy: Are we heading in the right direction?

    International Nuclear Information System (INIS)

    Evans, A.; Whelehan, P.

    2011-01-01

    There is a large body of evidence supporting 2-yearly screening of women aged 50-69 years. There is good evidence for a mortality reduction from mammographic screening in women aged 40 to 49 years but a 1-year interval is required. The lack of specificity of screening in young women does remain a problem. There is no evidence to suggest that a single screen between the ages of 47 and 50 years within a programme screening at 3-year intervals will reduce mortality; the trials showing a mortality benefit in women in their 40s included multiple screening episodes and shorter screening intervals. There is no randomized, controlled trial evidence to support screening in women aged above 70 years and screening this age group will cause greater harm than in younger women through higher rates of over-diagnosis and consequent over-treatment. The randomized phase of the screening age extension, which at the moment is planned to last only 6 years, should not be immediately followed by general implementation of the policy. Only if and when additional mortality reductions and an acceptable balance between benefit and harms are shown to be achieved by the extra screens should the 2007 Cancer Reform Strategy policy on age extension be implemented. Resources saved by delaying or abandoning the roll-out of the age extension could potentially be redirected towards reducing the current 3 year screening interval to 2 years in women aged 50-69 years. However, reducing the screening interval to 2 years for women aged 50-69 years would require significantly more screening invitations and resources than the proposed age extension.

  14. Cervical cancer screening policies and coverage in Europe

    DEFF Research Database (Denmark)

    Anttila, Ahti; von Karsa, Lawrence; Aasmaa, Auni

    2009-01-01

    The aim of the study was to compare current policy, organisation and coverage of cervical cancer screening programmes in the European Union (EU) member states with European and other international recommendations. According to the questionnaire-based survey, there are large variations in cervical...... cancer screening policies and inadequacies in the key organisational elements of the programme such as registration and monitoring required for quality-assurance and fail-safe mechanisms. Based on data from available screening registers, coverage of the screening test taken within the population...... with education, training and communication among women, medical professionals and authorities are required, accordingly. The study indicates that, despite substantial efforts, the recommendations of the Council of the EU on organised population-based screening for cervical cancer are not yet fulfilled. Decision...

  15. Systematic review of model-based cervical screening evaluations.

    Science.gov (United States)

    Mendes, Diana; Bains, Iren; Vanni, Tazio; Jit, Mark

    2015-05-01

    Optimising population-based cervical screening policies is becoming more complex due to the expanding range of screening technologies available and the interplay with vaccine-induced changes in epidemiology. Mathematical models are increasingly being applied to assess the impact of cervical cancer screening strategies. We systematically reviewed MEDLINE®, Embase, Web of Science®, EconLit, Health Economic Evaluation Database, and The Cochrane Library databases in order to identify the mathematical models of human papillomavirus (HPV) infection and cervical cancer progression used to assess the effectiveness and/or cost-effectiveness of cervical cancer screening strategies. Key model features and conclusions relevant to decision-making were extracted. We found 153 articles meeting our eligibility criteria published up to May 2013. Most studies (72/153) evaluated the introduction of a new screening technology, with particular focus on the comparison of HPV DNA testing and cytology (n = 58). Twenty-eight in forty of these analyses supported HPV DNA primary screening implementation. A few studies analysed more recent technologies - rapid HPV DNA testing (n = 3), HPV DNA self-sampling (n = 4), and genotyping (n = 1) - and were also supportive of their introduction. However, no study was found on emerging molecular markers and their potential utility in future screening programmes. Most evaluations (113/153) were based on models simulating aggregate groups of women at risk of cervical cancer over time without accounting for HPV infection transmission. Calibration to country-specific outcome data is becoming more common, but has not yet become standard practice. Models of cervical screening are increasingly used, and allow extrapolation of trial data to project the population-level health and economic impact of different screening policy. However, post-vaccination analyses have rarely incorporated transmission dynamics. Model calibration to country

  16. Optimization of PSA screening policies: a comparison of the patient and societal perspectives.

    Science.gov (United States)

    Zhang, Jingyu; Denton, Brian T; Balasubramanian, Hari; Shah, Nilay D; Inman, Brant A

    2012-01-01

    To estimate the benefit of PSA-based screening for prostate cancer from the patient and societal perspectives. A partially observable Markov decision process model was used to optimize PSA screening decisions. Age-specific prostate cancer incidence rates and the mortality rates from prostate cancer and competing causes were considered. The model trades off the potential benefit of early detection with the cost of screening and loss of patient quality of life due to screening and treatment. PSA testing and biopsy decisions are made based on the patient's probability of having prostate cancer. Probabilities are inferred based on the patient's complete PSA history using Bayesian updating. The results of all PSA tests and biopsies done in Olmsted County, Minnesota, from 1993 to 2005 (11,872 men and 50,589 PSA test results). Patients' perspective: to maximize expected quality-adjusted life years (QALYs); societal perspective: to maximize the expected monetary value based on societal willingness to pay for QALYs and the cost of PSA testing, prostate biopsies, and treatment. From the patient perspective, the optimal policy recommends stopping PSA testing and biopsy at age 76. From the societal perspective, the stopping age is 71. The expected incremental benefit of optimal screening over the traditional guideline of annual PSA screening with threshold 4.0 ng/mL for biopsy is estimated to be 0.165 QALYs per person from the patient perspective and 0.161 QALYs per person from the societal perspective. PSA screening based on traditional guidelines is found to be worse than no screening at all. PSA testing done with traditional guidelines underperforms and therefore underestimates the potential benefit of screening. Optimal screening guidelines differ significantly depending on the perspective of the decision maker.

  17. From Predictive Models to Instructional Policies

    Science.gov (United States)

    Rollinson, Joseph; Brunskill, Emma

    2015-01-01

    At their core, Intelligent Tutoring Systems consist of a student model and a policy. The student model captures the state of the student and the policy uses the student model to individualize instruction. Policies require different properties from the student model. For example, a mastery threshold policy requires the student model to have a way…

  18. Drug screening using model systems: some basics

    Directory of Open Access Journals (Sweden)

    Ross Cagan

    2016-11-01

    Full Text Available An increasing number of laboratories that focus on model systems are considering drug screening. Executing a drug screen is complicated enough. But the path for moving initial hits towards the clinic requires a different knowledge base and even a different mindset. In this Editorial I discuss the importance of doing some homework before you start screening. 'Lead hits', 'patentable chemical space' and 'druggability' are all concepts worth exploring when deciding which screening path to take. I discuss some of the lessons I learned that may be useful as you navigate the screening matrix.

  19. A computer simulation model for the practical planning of cervical cancer screening programmes.

    OpenAIRE

    Parkin, D. M.

    1985-01-01

    There is ample evidence of the efficacy of cytological screening in the prevention of cervical cancer but disagreement on the form which screening programmes should take. Simulation models have been used as a convenient and rapid method of exploring the outcome of different screening policies and of demonstrating the importance and interrelationships of the variables concerned. However, most such models are either too abstract or too simplistic to be of practical value in planning screening p...

  20. Driving licences and medical screening in old age: Review of literature and European licensing policies

    OpenAIRE

    Siren, Anu Kristiina; Haustein, Sonja

    2015-01-01

    Chronological age, per se, seems to be, in the case of mature drivers, only a weak predictor of safe driving performance. However, screening policies based on chronological age are widely used. Nevertheless, lately, more evidence-based policies have been called for. In this paper we first, investigate the evidence for and against having an age-based driver screening policy in place; second, we map and compare the current driving licensing policies in European Union (EU) member states in order...

  1. [Cost-effectiveness of breast cancer screening policies in Mexico].

    Science.gov (United States)

    Valencia-Mendoza, Atanacio; Sánchez-González, Gilberto; Bautista-Arredondo, Sergio; Torres-Mejía, Gabriela; Bertozzi, Stefano M

    2009-01-01

    Generate cost-effectiveness information to allow policy makers optimize breast cancer (BC) policy in Mexico. We constructed a Markov model that incorporates four interrelated processes of the disease: the natural history; detection using mammography; treatment; and other competing-causes mortality, according to which 13 different strategies were modeled. Strategies (starting age, % of coverage, frequency in years)= (48, 25, 2), (40, 50, 2) and (40, 50, 1) constituted the optimal method for expanding the BC program, yielding 75.3, 116.4 and 171.1 thousand pesos per life-year saved, respectively. The strategies included in the optimal method for expanding the program produce a cost per life-year saved of less than two times the GNP per capita and hence are cost-effective according to WHO Commission on Macroeconomics and Health criteria.

  2. Screening for Prediabetes Using Machine Learning Models

    Directory of Open Access Journals (Sweden)

    Soo Beom Choi

    2014-01-01

    Full Text Available The global prevalence of diabetes is rapidly increasing. Studies support the necessity of screening and interventions for prediabetes, which could result in serious complications and diabetes. This study aimed at developing an intelligence-based screening model for prediabetes. Data from the Korean National Health and Nutrition Examination Survey (KNHANES were used, excluding subjects with diabetes. The KNHANES 2010 data (n=4685 were used for training and internal validation, while data from KNHANES 2011 (n=4566 were used for external validation. We developed two models to screen for prediabetes using an artificial neural network (ANN and support vector machine (SVM and performed a systematic evaluation of the models using internal and external validation. We compared the performance of our models with that of a screening score model based on logistic regression analysis for prediabetes that had been developed previously. The SVM model showed the areas under the curve of 0.731 in the external datasets, which is higher than those of the ANN model (0.729 and the screening score model (0.712, respectively. The prescreening methods developed in this study performed better than the screening score model that had been developed previously and may be more effective method for prediabetes screening.

  3. Energy-economic policy modeling

    Science.gov (United States)

    Sanstad, Alan H.

    2018-01-01

    Computational models based on economic principles and methods are powerful tools for understanding and analyzing problems in energy and the environment and for designing policies to address them. Among their other features, some current models of this type incorporate information on sustainable energy technologies and can be used to examine their potential role in addressing the problem of global climate change. The underlying principles and the characteristics of the models are summarized, and examples of this class of model and their applications are presented. Modeling epistemology and related issues are discussed, as well as critiques of the models. The paper concludes with remarks on the evolution of the models and possibilities for their continued development.

  4. Modeling of global biomass policies

    International Nuclear Information System (INIS)

    Gielen, D.; Fujino, Junichi; Hashimoto, Seiji; Moriguchi, Yuichi

    2003-01-01

    This paper discusses the BEAP model and its use for the analysis of biomass policies for CO 2 emission reduction. The model considers competing land use, trade and leakage effects, and competing emission reduction strategies. Two policy scenarios are presented. In case of a 2040 time horizon the results suggest that a combination of afforestation and limited use of biomass for energy and materials constitutes the most attractive set of strategies. In case of a 'continued Kyoto' scenario including afforestation permit trade, the results suggest 5.1 Gt emission reduction based on land use change in 2020, two thirds of the total emission reduction by then. In case of global emission reduction, land use, land use change and forestry (LULUCF) accounts for one quarter of the emission reduction. However these results depend on the modeling time horizon. In case of a broader time horizon, maximized biomass production is more attractive than LULUCF. This result can be interpreted as a warning against a market based trading scheme for LULUCF credits. The model results suggest that the bioenergy market is dominated by transportation fuels and heating, and to a lesser extent feedstocks. Bioelectricity does not gain a significant market share in case competing CO 2 -free electricity options such as CO 2 capture and sequestration and nuclear are considered. To some extent trade in agricultural food products such as beef and cereals will be affected by CO 2 policies. (Author)

  5. Modeling of global biomass policies

    International Nuclear Information System (INIS)

    Gielen, Dolf; Fujino, Junichi; Hashimoto, Seiji; Moriguchi, Yuichi

    2003-01-01

    This paper discusses the BEAP model and its use for the analysis of biomass policies for CO 2 emission reduction. The model considers competing land use, trade and leakage effects, and competing emission reduction strategies. Two policy scenarios are presented. In case of a 2040 time horizon the results suggest that a combination of afforestation and limited use of biomass for energy and materials constitutes the most attractive set of strategies. In case of a 'continued Kyoto' scenario including afforestation permit trade, the results suggest 5.1 Gt emission reduction based on land use change in 2020, two thirds of the total emission reduction by then. In case of global emission reduction, land use, land use change and forestry (LULUCF) accounts for one quarter of the emission reduction. However these results depend on the modeling time horizon. In case of a broader time horizon, maximized biomass production is more attractive than LULUCF. This result can be interpreted as a warning against a market based trading scheme for LULUCF credits. The model results suggest that the bioenergy market is dominated by transportation fuels and heating, and to a lesser extent feedstocks. Bioelectricity does not gain a significant market share in case competing CO 2 -free electricity options such as CO 2 capture and sequestration and nuclear are considered. To some extent trade in agricultural food products such as beef and cereals will be affected by CO 2 policies

  6. Policy advice derived from simulation models

    NARCIS (Netherlands)

    Brenner, T.; Werker, C.

    2009-01-01

    When advising policy we face the fundamental problem that economic processes are connected with uncertainty and thus policy can err. In this paper we show how the use of simulation models can reduce policy errors. We suggest that policy is best based on socalled abductive simulation models, which

  7. Driving licences and medical screening in old age: Review of literature and European licensing policies

    DEFF Research Database (Denmark)

    Siren, Anu Kristiina; Haustein, Sonja

    2015-01-01

    , investigate the evidence for and against having an age-based driver screening policy in place; second, we map and compare the current driving licensing policies in European Union (EU) member states in order to examine the variation; and third, we draw conclusions based on the literature and the policy mapping......Chronological age, per se, seems to be, in the case of mature drivers, only a weak predictor of safe driving performance. However, screening policies based on chronological age are widely used. Nevertheless, lately, more evidence-based policies have been called for. In this paper we first...... and provide policy recommendations. We find no evidence from the literature demonstrating that the benefits from age-based driver screening would outweigh the disadvantages, and we find the European policies, to a large extent, coercive and not evidence based. Based on research evidence, the policies...

  8. Introduction: mass screening, health technology assessment, and health policy in some European countries.

    NARCIS (Netherlands)

    Oortwijn, W.J.; Banta, H.D.; Cranovsky, R.

    2001-01-01

    OBJECTIVE: The series of papers in this issue was developed to examine the use of health technology assessment in policies toward prevention-specifically toward mass screening-in European countries. The papers actually examined three screening strategies: mammography screening for breast cancer,

  9. Screening Mental Health Problems in Schools. A Center Policy Issues Analysis Brief

    Science.gov (United States)

    Center for Mental Health in Schools at UCLA, 2007

    2007-01-01

    Long-standing policy controversies have heated up as a result of increasing proposals for using schools to screen for mental health problems (e.g., depression screening). This brief highlights the following issues: (1) How appropriate is large-scale screening for mental health problems? (2) Will the costs of large-scale mental health screening…

  10. Driving licences and medical screening in old age: Review of literature and European licensing policies

    DEFF Research Database (Denmark)

    Siren, Anu Kristiina; Haustein, Sonja

    2015-01-01

    , investigate the evidence for and against having an age-based driver screening policy in place; second, we map and compare the current driving licensing policies in European Union (EU) member states in order to examine the variation; and third, we draw conclusions based on the literature and the policy mapping...

  11. Economic Models as Devices of Policy Change

    DEFF Research Database (Denmark)

    Henriksen, Lasse Folke

    2013-01-01

    Can the emergence of a new policy model be a catalyst for a paradigm shift in the overall interpretative framework of how economic policy is conducted within a society? This paper claims that models are understudied as devices used by actors to induce policy change. This paper explores the role...... the extent to which the performativity approach can help identify macroscopic changes in policy from seemingly microscopic changes in policy models. The concept of performativity is explored as a means of thinking about the constitution of agency directed at policy change. The paper brings this concept...

  12. Breast cancer screening policies in developing countries: a cost-effectiveness analysis for India.

    Science.gov (United States)

    Okonkwo, Quirine Lamberts; Draisma, Gerrit; der Kinderen, Arno; Brown, Martin L; de Koning, Harry J

    2008-09-17

    India, the largest developing country, has a steadily rising incidence of breast cancer. Estimates and comparisons of the cost-effectiveness of feasible breast cancer screening policies in developing countries and identification of the determinants of cost and efficacy are needed. A Microsimulation Screening Analysis model of breast cancer was calibrated to available data on breast cancer incidence, stage distribution, and mortality in India. The model was used to estimate the costs of screening for breast cancer in India, its effects on mortality, and its cost-effectiveness (ie, costs of screening per life-year gained or life saved). Screening using clinical breast examination (CBE) or mammography among different age groups and at various frequencies was analyzed. Costs were expressed in international dollars (Int.$), the currency used by the World Health Organization, which has the same purchasing power in India as the US dollar has in the United States. To determine which factors influenced cost-effectiveness, sensitivity analyses were performed. The estimated mortality reduction was the greatest for programs targeting women between age 40 and 60 years. Using a 3% discount rate, a single CBE at age 50 had an estimated cost-effectiveness ratio of Int.$793 per life year gained and a breast cancer mortality reduction of 2%. The cost-effectiveness ratio increased to Int.$1135 per life year gained for every-5-year CBE (age 40-60 years) and to Int.$1341 for biennial CBE (age 40-60 years); the corresponding reductions in breast cancer mortality were 8.2% and 16.3%, respectively. CBE performed annually from ages 40 to 60 was predicted to be nearly as efficacious as biennial mammography screening for reducing breast cancer mortality while incurring only half the net costs. The main factors affecting cost-effectiveness were breast cancer incidence, stage distribution, and cost savings on prevented palliative care. The estimated cost-effectiveness of CBE screening for

  13. An endogenous policy model of hierarchical government

    NARCIS (Netherlands)

    Mazza, I.; van Winden, F.

    2008-01-01

    Endogenous policy models usually neglect that government policies are frequently the result of decisions taken at different tiers by different agents, each enjoying some degree of autonomy. In this paper, policies are the outcome of the choices made by two agents within a hierarchy. A legislator

  14. Towards increased policy relevance in energy modeling

    Energy Technology Data Exchange (ETDEWEB)

    Worrell, Ernst; Ramesohl, Stephan; Boyd, Gale

    2003-07-29

    Historically, most energy models were reasonably equipped to assess the impact of a subsidy or change in taxation, but are often insufficient to assess the impact of more innovative policy instruments. We evaluate the models used to assess future energy use, focusing on industrial energy use. We explore approaches to engineering-economic analysis that could help improve the realism and policy relevance of engineering-economic modeling frameworks. We also explore solutions to strengthen the policy usefulness of engineering-economic analysis that can be built from a framework of multi-disciplinary cooperation. We focus on the so-called ''engineering-economic'' (or ''bottom-up'') models, as they include the amount of detail that is commonly needed to model policy scenarios. We identify research priorities for the modeling framework, technology representation in models, policy evaluation and modeling of decision-making behavior.

  15. Stochastic modeling for environmental stress screening

    OpenAIRE

    Cha, Ji Hwan; Finkelstein, Maxim

    2014-01-01

    Environmental stress screening (ESS) of manufactured items is used to reduce the occurrence of future failures that are caused by latent defects by eliminating the items with these defects. Some practical descriptions of the relevant ESS procedures can be found in the literature; however, the appropriate stochastic modeling and the corresponding thorough analysis have not been reported. In this paper we develop a stochastic model for the ESS, analyze the effect of this operation o...

  16. How does early detection by screening affect disease progression?: Modeling estimated benefits in prostate cancer screening

    NARCIS (Netherlands)

    E.M. Wever (Elisabeth); G. Draisma (Gerrit); E.A.M. Heijnsdijk (Eveline); H.J. de Koning (Harry)

    2011-01-01

    textabstractBackground. Simulation models are essential tools for estimating benefits of cancer screening programs. Such models include a screening-effect model that represents how early detection by screening followed by treatment affects disease-specific survival. Two commonly used

  17. Policy Forum Improving the screening and treatment of hypertension ...

    African Journals Online (AJOL)

    2008-12-27

    Dec 27, 2008 ... of these patients are unaware and therefore untreated.3. In a small HIV-infected cohort in Blantyre, 46% of patients were found to have elevated blood pressure.4. The lack of a well organised and funded national hypertension screening and treatment programme leaves hypertension in patients poorly ...

  18. Resilience of a FIT screening programme against screening fatigue: a modelling study

    Directory of Open Access Journals (Sweden)

    Marjolein J. E. Greuter

    2016-09-01

    Full Text Available Abstract Background Repeated participation is important in faecal immunochemical testing (FIT screening for colorectal cancer (CRC. However, a large number of screening invitations over time may lead to screening fatigue and consequently, decreased participation rates. We evaluated the impact of screening fatigue on overall screening programme effectiveness. Methods Using the ASCCA model, we simulated the Dutch CRC screening programme consisting of biennial FIT screening in individuals aged 55–75. We studied the resilience of the programme against heterogeneity in screening attendance and decrease in participation rate due to screening fatigue. Outcomes were reductions in CRC incidence and mortality compared to no screening. Results Assuming a homogenous 63 % participation, i.e., each round each individual was equally likely to attend screening, 30 years of screening reduced CRC incidence and mortality by 39 and 53 %, respectively, compared to no screening. When assuming clustered participation, i.e., three subgroups of individuals with a high (95 %, moderate (65 % and low (5 % participation rate, screening was less effective; reductions were 33 % for CRC incidence and 43 % for CRC mortality. Screening fatigue considerably reduced screening effectiveness; if individuals refrained from screening after three negative screens, model-predicted incidence reductions decreased to 25 and 18 % under homogenous and clustered participation, respectively. Figures were 34 and 25 % for mortality reduction. Conclusions Screening will substantially decrease CRC incidence and mortality. However, screening effectiveness can be seriously compromised if screening fatigue occurs. This warrants careful monitoring of individual screening behaviour and consideration of targeted invitation systems in individuals who have (repeatedly missed screening rounds.

  19. Screening for a Chronic Disease: A Multiple Stage Duration Model with Partial Observability.

    Science.gov (United States)

    Mroz, Thomas A; Picone, Gabriel; Sloan, Frank; Yashkin, Arseniy P

    2016-08-01

    We estimate a dynamic multi-stage duration model to investigate how early detection of diabetes can delay the onset of lower extremity complications and death. We allow for partial observability of the disease stage, unmeasured heterogeneity, and endogenous timing of diabetes screening. Timely diagnosis appears important. We evaluate the effectiveness of two potential policies to reduce the monetary costs of frequent screening in terms of lost longevity. Compared to the status quo, the more restrictive policy yields an implicit value for an additional year of life of about $50,000, while the less restrictive policy implies a value of about $120,000.

  20. Modelling the Effects and Costs of Colorectal Cancer Screening

    NARCIS (Netherlands)

    S.L. Goede (Luuk)

    2015-01-01

    markdownabstract__Abstract__ The thesis focused on the potential effects and costs of population-based colorectal cancer (CRC) screening by considering two overarching questions. In the first part of the thesis the potential impact of current screening policies on the CRC disease burden and costs

  1. Screening design for model sensitivity studies

    Science.gov (United States)

    Welsh, James P.; Koenig, George G.; Bruce, Dorothy

    1997-07-01

    This paper describes a different approach to sensitivity studies for environmental, including atmospheric, physics models. The sensitivity studies were performed on a multispectral environmental data and scene generation capability. The capability includes environmental physics models that are used to generate data and scenes for simulation of environmental materials, features, and conditions, such as trees, clouds, soils, and snow. These studies were performed because it is difficult to obtain input data for many of the environmental variables. The problem to solve is to determine which of the 100 or so input variables, used by the generation capability, are the most important. These sensitivity studies focused on the generation capabilities needed to predict and evaluate the performance of sensor systems operating in the infrared portions of the electromagnetic spectrum. The sensitivity study approach described uses a screening design. Screening designs are analytical techniques that use a fraction of all of the combinations of the potential input variables and conditions to determine which are the most important. Specifically a 20-run Plackett-Burman screening design was used to study the sensitivity of eight data and scene generation capability computed response variables to 11 selected input variables. This is a two-level design, meaning that the range of conditions is represented by two different values for each of the 11 selected variables. The eight response variables used were maximum, minimum, range, and mode of the model-generated temperature and radiance values. The result is that six of the 11 input variables (soil moisture, solar loading, roughness length, relative humidity, surface albedo, and surface emissivity) had a statistically significant effect on the response variables.

  2. Modeling screening, prevention, and delaying of Alzheimer's disease: an early-stage decision analytic model

    Directory of Open Access Journals (Sweden)

    Siemers Eric R

    2010-04-01

    Full Text Available Abstract Background Alzheimer's Disease (AD affects a growing proportion of the population each year. Novel therapies on the horizon may slow the progress of AD symptoms and avoid cases altogether. Initiating treatment for the underlying pathology of AD would ideally be based on biomarker screening tools identifying pre-symptomatic individuals. Early-stage modeling provides estimates of potential outcomes and informs policy development. Methods A time-to-event (TTE simulation provided estimates of screening asymptomatic patients in the general population age ≥55 and treatment impact on the number of patients reaching AD. Patients were followed from AD screen until all-cause death. Baseline sensitivity and specificity were 0.87 and 0.78, with treatment on positive screen. Treatment slowed progression by 50%. Events were scheduled using literature-based age-dependent incidences of AD and death. Results The base case results indicated increased AD free years (AD-FYs through delays in onset and a reduction of 20 AD cases per 1000 screened individuals. Patients completely avoiding AD accounted for 61% of the incremental AD-FYs gained. Total years of treatment per 1000 screened patients was 2,611. The number-needed-to-screen was 51 and the number-needed-to-treat was 12 to avoid one case of AD. One-way sensitivity analysis indicated that duration of screening sensitivity and rescreen interval impact AD-FYs the most. A two-way sensitivity analysis found that for a test with an extended duration of sensitivity (15 years the number of AD cases avoided was 6,000-7,000 cases for a test with higher sensitivity and specificity (0.90,0.90. Conclusions This study yielded valuable parameter range estimates at an early stage in the study of screening for AD. Analysis identified duration of screening sensitivity as a key variable that may be unavailable from clinical trials.

  3. How does early detection by screening affect disease progression? Modeling estimated benefits in prostate cancer screening.

    Science.gov (United States)

    Wever, Elisabeth M; Draisma, Gerrit; Heijnsdijk, Eveline A M; de Koning, Harry J

    2011-01-01

    Simulation models are essential tools for estimating benefits of cancer screening programs. Such models include a screening-effect model that represents how early detection by screening followed by treatment affects disease-specific survival. Two commonly used screening-effect models are the stage-shift model, where mortality benefits are explained by the shift to more favorable stages, and the cure model, where early detection enhances the chances of cure from disease. This article describes commonly used screening-effect models and analyses their predicted mortality benefit in a model for prostate cancer screening. The MISCAN simulation model was used to predict the reduction of prostate cancer mortality in the European Randomized Study of Screening for Prostate Cancer (ERSPC) Rotterdam. The screening-effect models were included in the model. For each model the predictions of prostate cancer mortality reduction were calculated. The study compared 4 screening-effect models, which are versions of the stage-shift model or the cure model. The stage-shift models predicted, after a follow-up of 9 years, reductions in prostate cancer mortality varying from 38% to 63% for ERSPC-Rotterdam compared with a 27% reduction observed in the ERSPC. The cure models predicted reductions in prostate cancer mortality varying from 21% to 27%. The differences in predicted mortality reductions show the importance of validating models to observed trial mortality data. The stage-shift models considerably overestimated the mortality reduction. Therefore, the stage-shift models should be used with care, especially when modeling the effect of screening for cancers with long lead times, such as prostate cancer.

  4. Policy modeling for industrial energy use

    Energy Technology Data Exchange (ETDEWEB)

    Worrell, Ernst; Park, Hi-Chun; Lee, Sang-Gon; Jung, Yonghun; Kato, Hiroyuki; Ramesohl, Stephan; Boyd, Gale; Eichhammer, Wolfgang; Nyboer, John; Jaccard, Mark; Nordqvist, Joakim; Boyd, Christopher; Klee, Howard; Anglani, Norma; Biermans, Gijs

    2003-03-01

    The international workshop on Policy Modeling for Industrial Energy Use was jointly organized by EETA (Professional Network for Engineering Economic Technology Analysis) and INEDIS (International Network for Energy Demand Analysis in the Industrial Sector). The workshop has helped to layout the needs and challenges to include policy more explicitly in energy-efficiency modeling. The current state-of-the-art models have a proven track record in forecasting future trends under conditions similar to those faced in the recent past. However, the future of energy policy in a climate-restrained world is likely to demand different and additional services to be provided by energy modelers. In this workshop some of the international models used to make energy consumption forecasts have been discussed as well as innovations to enable the modeling of policy scenarios. This was followed by the discussion of future challenges, new insights in the data needed to determine the inputs into energy model s, and methods to incorporate decision making and policy in the models. Based on the discussion the workshop participants came to the following conclusions and recommendations: Current energy models are already complex, and it is already difficult to collect the model inputs. Hence, new approaches should be transparent and not lead to extremely complex models that try to ''do everything''. The model structure will be determined by the questions that need to be answered. A good understanding of the decision making framework of policy makers and clear communication on the needs are essential to make any future energy modeling effort successful. There is a need to better understand the effects of policy on future energy use, emissions and the economy. To allow the inclusion of policy instruments in models, evaluation of programs and instruments is essential, and need to be included in the policy instrument design. Increased efforts are needed to better understand the

  5. Hepatitis B prevalence in the Turkish population of Arnhem: implications for national screening policy?

    NARCIS (Netherlands)

    Richter, C.; Beest, G.T.; Sancak, I.; Aydinly, R.; Bulbul, K.; Laetemia-Tomata, F.; De Leeuw, M.; Waegemaekers, T.; Swanink, C.; Roovers, E.

    2012-01-01

    Despite the increased prevalence of hepatitis B and C in most migrant groups in The Netherlands, a national screening policy for these infections is not available. In order to estimate the prevalence of hepatitis B and C in the largest group of first-generation migrants (FGM) in The Netherlands, we

  6. Policy and Evidence: A Critical Analysis of the Year 1 Phonics Screening Check in England

    Science.gov (United States)

    Grundin, Hans U.

    2018-01-01

    This paper aims to present a critical analysis of the Year 1 Phonics Screening Check (PSC), with special focus on the relationship between the UK Department for Education's policy-making and the evidence considered in the process of developing and evaluating the PSC. The reports from the in-house Standards and Testing Agency and from commissioned…

  7. Screening Mammography: Science, Policy and Politics–The Good, the Bad and the Ugly

    Science.gov (United States)

    Diana Petitti, MD, MPH, FACPM, an epidemiologic expert on women's health and evidence based medicine, with posts as vice chair and spokesperson for the U.S. Preventive Service Task Force, presented "Screening Mammography: Science, Policy and Politics–The Good, the Bad and the Ugly." 

  8. Prostate cancer screening using risk stratification based on a multi-state model of genetic variants.

    Science.gov (United States)

    Yen, Amy Ming-Fang; Auvinen, Anssi; Schleutker, Johanna; Wu, Yi-Ying; Fann, Jean Ching-Yuan; Tammela, Teuvo; Chen, Sam Li-Sheng; Chiu, Sherry Yueh-Hsia; Chen, Hsiu-Hsi

    2015-06-01

    Risk-stratified screening for prostate cancer (PCa) with prostate-specific antigen (PSA) testing incorporating genetic variants has received some attention but has been scarcely investigated. We developed a model to stratify the Finnish population by different risk profiles related to genetic variants to optimize the screening policy. Data from the Finnish randomized controlled trial on screening for PCa with PSA testing were used to estimate a six-state Markov model of disease progression. Blood samples from Finnish men were used to assess the risk of PCa related to three genetic variants (rs4242382, rs138213197, and rs200331695). A risk score-based approach combined with a series of computer simulation models was applied to optimize individual screening policies. The 10-year risk of having progressive prostate cancer detected ranged from 43% in the top 5% risk group to approximately 11% in the bottom half of the population. Using the median group, with screening every four years beginning at 55 years-old, as the reference group, the recommended age beginning screening was approximately 47 years-old for the top 5% risk group and 55 years-old for those in the lower 60% risk group. The recommended interscreening interval has been shortened for individuals in the high risk group. The increased availability of genomic information allows the proposed multistate model to be more discriminating with respect to risk stratification and the suggested screening policy, particularly for the lowest risk groups-. -- A multi-state genetic variant-based model was developed for further application to population risk stratification to optimize the interscreening interval and the age at which to begin screening for PSA. A small sub-group of the population is likely to benefit from more intensive screening with early start and short interval, while half of the population is unlikely to benefit from such protocol (compared with four-year interval after age 55 years). © 2015 Wiley

  9. [Factors associated with gastric cancer screening of Koreans based on a socio-ecological model].

    Science.gov (United States)

    Bae, Sang Soo; Jo, Heui Sug; Kim, Dong-Hyun; Choi, Yong-Jun; Lee, Hun Jae; Lee, Tae Jin; Lee, Hye Jean

    2008-03-01

    We measured behavioral factors associated with Koreans receiving gastric cancer screening based on a socio-ecological model, in part to develop strategies to improve cancer screening rates. A telephone survey was conducted with 2,576 people chosen through stratified random sampling from April 1--May 31, 2004. Collected information included gastric cancer screening, socio-demographic factors, and socio-ecological factors at intrapersonal, interpersonal, community, and public policy levels. Among 985 survey respondents (380 men and 605 women), 402 had received gastric cancer screening. Logistic analysis was performed to compare those screened and unscreened. 'Age' was the only demographic factor that showed a statistically significant association with getting screening. People in their fifties (OR=1.731, 95% CI=1.190-2.520) and sixties (OR=2.098, 95% CI=1.301-3.385) showed a higher likelihood of getting screened, compared to those in the forties. 'Accessibility to a medical institution' was a significant factor related to having gastric cancer screening at the intrapersonal level. At the interpersonal level, recommendations by family members to be screened and a family practice of routine cancer screening were significantly related. People with frequent education about cancer screening or with stronger social feelings that cancer screening is necessary also demonstrated significantly higher tendencies to be screened. In conclusion, a socio-ecological model seems appropriate for explaining gastric cancer screening behavior and associated factors. Health planners should develop integrated strategies to improve cancer screening rates based on socio-ecological factors, especially at the interpersonal and community levels.

  10. Screening for prostatic cancer. Investigational models

    DEFF Research Database (Denmark)

    Iversen, P; Torp-Pedersen, S T

    1991-01-01

    features of the disease, which make the possible gain from screening programs questionable. Thus, before embarking on expensive community or national screening programs, the beneficial effect of such an effort on morbidity and mortality must be demonstrated in large-scale trials comparing a screened...

  11. Modeling Hepatitis C treatment policy.

    Energy Technology Data Exchange (ETDEWEB)

    Kuypers, Marshall A.; Lambert, Gregory Joseph; Moore, Thomas W.; Glass, Robert John,; Finley, Patrick D.; Ross, David; Chartier, Maggie

    2013-09-01

    Chronic infection with Hepatitis C virus (HCV) results in cirrhosis, liver cancer and death. As the nations largest provider of care for HCV, US Veterans Health Administration (VHA) invests extensive resources in the diagnosis and treatment of the disease. This report documents modeling and analysis of HCV treatment dynamics performed for the VHA aimed at improving service delivery efficiency. System dynamics modeling of disease treatment demonstrated the benefits of early detection and the role of comorbidities in disease progress and patient mortality. Preliminary modeling showed that adherence to rigorous treatment protocols is a primary determinant of treatment success. In depth meta-analysis revealed correlations of adherence and various psycho-social factors. This initial meta-analysis indicates areas where substantial improvement in patient outcomes can potentially result from VA programs which incorporate these factors into their design.

  12. Towards modelling cost and risks of infrequent events in the cargo screening process

    OpenAIRE

    Sherman, Galina; Menachof, David; Siebers, Peer-Olaf; Aickelin, Uwe

    2013-01-01

    We introduce a simulation model of the port of Calais with a focus on the operation of immigration controls. Our aim is to compare the cost and benefits of different screening policies. Methodologically, we are trying to understand the limits of discrete event simulation of rare events. When will they become 'too rare' for simulation to give meaningful results?

  13. Genetic screens in Caenorhabditis elegans models for neurodegenerative diseases

    NARCIS (Netherlands)

    Alvarenga Fernandes Sin, Olga; Michels, Helen; Nollen, Ellen A. A.

    2014-01-01

    Caenorhabditis elegans comprises unique features that make it an attractive model organism in diverse fields of biology. Genetic screens are powerful to identify genes and C. elegans can be customized to forward or reverse genetic screens and to establish gene function. These genetic screens can be

  14. A Drosophila Model for Screening Antiobesity Agents

    Directory of Open Access Journals (Sweden)

    Tran Thanh Men

    2016-01-01

    Full Text Available Although triacylglycerol, the major component for lipid storage, is essential for normal physiology, its excessive accumulation causes obesity in adipose tissue and is associated with organ dysfunction in nonadipose tissue. Here, we focused on the Drosophila model to develop therapeutics for preventing obesity. The brummer (bmm gene in Drosophila melanogaster is known to be homologous with human adipocyte triglyceride lipase, which is related to the regulation of lipid storage. We established a Drosophila model for monitoring bmm expression by introducing the green fluorescent protein (GFP gene as a downstream reporter of the bmm promoter. The third-instar larvae of Drosophila showed the GFP signal in all tissues observed and specifically in the salivary gland nucleus. To confirm the relationship between bmm expression and obesity, the effect of oral administration of glucose diets on bmm promoter activity was analyzed. The Drosophila flies given high-glucose diets showed higher lipid contents, indicating the obesity phenotype; this was suggested by a weaker intensity of the GFP signal as well as reduced bmm mRNA expression. These results demonstrated that the transgenic Drosophila model established in this study is useful for screening antiobesity agents. We also report the effects of oral administration of histone deacetylase inhibitors and some vegetables on the bmm promoter activity.

  15. Modelling mobility aspects of security policies

    NARCIS (Netherlands)

    Hartel, Pieter H.; van Eck, Pascal; Etalle, Sandro; Wieringa, Roelf J.

    Security policies are rules that constrain the behaviour of a system. Different, largely unrelated sets of rules typically govern the physical and logical worlds. However, increased hardware and software mobility forces us to consider those rules in an integrated fashion. We present SPIN models of

  16. Cancer risk models and preselection for screening

    NARCIS (Netherlands)

    Stegeman, Inge; Bossuyt, Patrick M.

    2012-01-01

    Objective: The invitation to population screening is based on age criteria in many countries. Screening is not offered to younger or older participants, because the benefits in these age groups do not outweigh the harms. One could argue that it is not so much age that determines the benefits but the

  17. European Cohesion Policy: A Proposed Evaluation Model

    Directory of Open Access Journals (Sweden)

    Alina Bouroşu (Costăchescu

    2012-06-01

    Full Text Available The current approach of European Cohesion Policy (ECP is intended to be a bridge between different fields of study, emphasizing the intersection between "the public policy cycle, theories of new institutionalism and the new public management”. ECP can be viewed as a focal point between putting into practice the principles of the new governance theory, theories of economic convergence and divergence and the governance of common goods. After a short introduction of defining the concepts used, the author discussed on the created image of ECP by applying three different theories, focusing on the structural funds implementation system (SFIS, directing the discussion on the evaluation part of this policy, by proposing a model of performance evaluation of the system, in order to outline key principles for creating effective management mechanisms of ECP.

  18. Impact of Policies on Physical Activity and Screen Time Practices in 50 Child-Care Centers in North Carolina.

    Science.gov (United States)

    Erinosho, Temitope; Hales, Derek; Vaughn, Amber; Mazzucca, Stephanie; Ward, Dianne S

    2016-01-01

    This study assessed physical activity and screen time policies in child-care centers and their associations with physical activity and screen time practices and preschool children's (3-5 years old) physical activity. Data were from 50 child-care centers in North Carolina. Center directors reported on the presence/absence of written policies. Trained research assistants observed physical activity and screen time practices in at least 1 preschool classroom across 3 to 4 days. Children (N = 544) wore accelerometers to provide an objective measure of physical activity. Physical activity and screen time policies varied across centers. Observational data showed 82.7 min/d of active play opportunities were provided to children. Screen time provided did not exceed 30 min/d/child at 98% of centers. Accelerometer data showed children spent 38 min/d in moderate-to-vigorous physical activity and 206 min/d in sedentary activity. Policies about staff supervision of media use were negatively associated with screen time (P < .05). Contrary to expectation, policies about physical activity were associated with less time in physical activity. Clear strategies are needed for translating physical activity policies to practice. Further research is needed to evaluate the quality of physical activity policies, their impact on practice, and ease of operationalization.

  19. Dynamic energy models and carbon mitigation policies

    Science.gov (United States)

    Tilley, Luke A.

    In this dissertation I examine a specific class of energy models and their implications for carbon mitigation policies. The class of models includes a production function capable of reproducing the empirically observed phenomenon of short run rigidity of energy use in response to energy price changes and long run exibility of energy use in response to energy price changes. I use a theoretical model, parameterized using empirical data, to simulate economic performance under several tax regimes where taxes are levied on capital income, investment, and energy. I also investigate transitions from one tax regime to another. I find that energy taxes intended to reduce energy use can successfully achieve those goals with minimal or even positive impacts on macroeconomic performance. But the transition paths to new steady states are lengthy, making political commitment to such policies very challenging.

  20. State-Mandated Nutrition, Physical Activity, and Screen Time Policies in Child Care Centers.

    Science.gov (United States)

    Chang-Martinez, Catherina; Ahmed, Nasar U; Natale, Ruby A; Messiah, Sarah E

    2017-09-01

    The child care center (CCC) environment presents opportunities for healthy weight promotion in preschoolers. Our study examined the current state of CCC adherence to nutrition, physical activity, and screen time legislative regulations and the differences in their adherence by center socioeconomic position (SEP: low, middle, high) in Miami-Dade County. In 34 CCC, we used the Environment and Policy Assessment and Observation tool to evaluate nutrition, physical activity, and screen time practices during 1-school day. Twenty-five of the centers (73.5%) were participants of the Child and Adult Care Food Program. Almost 80% of the centers adhered to serving low-fat/fat-free milk to children older than 2 years. Only 34.5% served vegetables and 75.9% served whole fruits during meals/snacks. Ninety-four percent of the centers had quiet and active play incorporated into their daily routines. All centers adhered to the 2-hour screen time limit for children older than 2 years. Low- and middle-SEP centers fared better in the serving of fruits, vegetables, and low-fat/fat-free milk. The centers averaged 1 hour in outdoor play regardless of SEP. High-SEP centers had no TV or screen time during day of observation. CCC practices highlight opportunities for improvement in nutrition, physical activity, and screen time practices in the prevention of overweight in early childhood.

  1. A Systematic Review of the Factors Influencing Ethnic Minority Women's Cervical Cancer Screening Behavior: From Intrapersonal to Policy Level.

    Science.gov (United States)

    Chan, Dorothy N S; So, Winnie K W

    Cervical cancer can be prevented by effective screening using Papanicolaou tests, but the utilization rate is lower among ethnic minorities than in the general population. Understanding the factors influencing minorities' use of such screening can aid the design of an appropriate intervention to increase their uptake rate. The aims of this study were to examine the factors that influence ethnic minority women in using cervical cancer screening and the similarities and differences in associated factors across different groups and to explore the interrelationships between the factors identified. A literature search was conducted using Ovid MEDLINE, Cumulative Index to Nursing and Allied Health Literature Plus, Scopus, PsycINFO, and PubMed. Furthermore, 1390 articles were retrieved, of which 24 met the inclusion criteria. Critical appraisal was performed by means of a quality assessment tool. The findings were summarized in tabular and narrative forms. The findings showed that certain factors commonly affected ethnic minority women's screening behavior, including knowledge, attitude and perceptions, physician's recommendation, quality of care and service, language, and acculturation. Culture-related factors, religion, and acculturation exhibited close interrelationships with the attitude and perceptions factor, resulting in behavioral change. The review sheds light on how common or unique are the factors across ethnic minorities and how these factors interact to influence behavior. Further studies are warranted to develop and test empirically a comprehensive model leading to a better understanding of the interrelationships between multiple factors. The model should be useful in informing policy makers about appropriate resource allocation and in guiding the development of culturally relevant programs to increase screening uptake.

  2. [Economic impact of lung cancer screening in France: A modeling study].

    Science.gov (United States)

    Gendarme, S; Perrot, É; Reskot, F; Bhoowabul, V; Fourre, G; Souquet, P-J; Milleron, B; Couraud, S

    2017-09-01

    The National Lung Screening Trial found that, in a selected population with a high risk of lung cancer, an annual low-dose CT-scan decreased lung cancer mortality by 20% and overall mortality by 7% compared to annual chest X-Ray. In France, a work group stated that individual screening should be considered in this setting. However, the economic impact of an organized and generalized (to all eligible individuals) screening in France was never reported. This is a modeling study using French population demographic data and published data from randomized screening trials. We used the same selection criteria as NLST: 55-74-year-old smokers for at least 30 pack-years, current smoker or quit less than 15 years. We computed a second model including also 50-54-year-old individuals. Then, we used different participation rates: 65%, 45%, and 32%. According to the considered model, there would be 1,650,588 to 2,283,993 subjects eligible to screening in France. According to the model and participation rate, lung cancer screening would diagnose 3600 to 10,118 stages 1/2 lung cancer each year. There would be 5991 to 16,839 false-positives, of whom 1416 to 3981 would undergo unnecessary surgery. Screening policy would cost 105 to 215 € million per year. However, increasing the price of a cigarette pack by 0.05 to 0.10 € would fully cover the screening costs. Participation rate is a key point for screening impact. Screening could be easily funded by a small increase in cigarette prices. Copyright © 2015 SPLF. Published by Elsevier Masson SAS. All rights reserved.

  3. Comparing the outcomes of two strategies for colorectal tumor detection: Policy-promoted screening program versus health promotion service

    Directory of Open Access Journals (Sweden)

    Ping-Hsiu Wu

    2013-06-01

    Conclusion: In comparison with the outcomes of the HPS database, the screening efficacy of the PPS database is even for detecting colorectal carcinoma but is limited in detecting advanced adenoma. HPS may provide comprehensive validity indicators and will be helpful in adjusting current policies for improving screening performance.

  4. A Multiscale Model Evaluates Screening for Neoplasia in Barrett's Esophagus.

    Directory of Open Access Journals (Sweden)

    Kit Curtius

    2015-05-01

    Full Text Available Barrett's esophagus (BE patients are routinely screened for high grade dysplasia (HGD and esophageal adenocarcinoma (EAC through endoscopic screening, during which multiple esophageal tissue samples are removed for histological analysis. We propose a computational method called the multistage clonal expansion for EAC (MSCE-EAC screening model that is used for screening BE patients in silico to evaluate the effects of biopsy sampling, diagnostic sensitivity, and treatment on disease burden. Our framework seamlessly integrates relevant cell-level processes during EAC development with a spatial screening process to provide a clinically relevant model for detecting dysplastic and malignant clones within the crypt-structured BE tissue. With this computational approach, we retain spatio-temporal information about small, unobserved tissue lesions in BE that may remain undetected during biopsy-based screening but could be detected with high-resolution imaging. This allows evaluation of the efficacy and sensitivity of current screening protocols to detect neoplasia (dysplasia and early preclinical EAC in the esophageal lining. We demonstrate the clinical utility of this model by predicting three important clinical outcomes: (1 the probability that small cancers are missed during biopsy-based screening, (2 the potential gains in neoplasia detection probabilities if screening occurred via high-resolution tomographic imaging, and (3 the efficacy of ablative treatments that result in the curative depletion of metaplastic and neoplastic cell populations in BE in terms of the long-term impact on reducing EAC incidence.

  5. Intimate Partner Violence Screening and Response: Policies and Procedures Across Health Care Facilities.

    Science.gov (United States)

    Williams, Jessica R; Halstead, Valerie; Salani, Deborah; Koermer, Natasha

    2016-01-01

    This study examines policies and procedures for identifying and responding to intimate partner violence (IPV) among different types of health care settings. This epidemiologic, cross-sectional, observational study design collected data from June 2014 to January 2015 through a telephone questionnaire from a stratified random sample of 288 health care facilities in Miami-Dade County, Florida. An overall response rate of 76.2% was achieved from 72 primary care clinics, 93 obstetrics/gynecology clinics, 106 pediatric clinics, and 17 emergency departments (EDs). There is a general awareness of the importance of IPV screening with 78.1% of facilities (95% CI, 73.9%-82.3%) reporting some type of IPV screening procedures. Wide variation exists, however, in how practices are implemented, with only 35.3% of facilities (95% CI, 29.5%-41.1%) implementing multicomponent, comprehensive IPV screening and response programs. Differences were also observed by setting with EDs reporting the most comprehensive programs. This study yields important empirical information regarding the extent to which IPV screening and response procedures are currently being implemented in both clinic and acute health care settings along with areas where improvements are needed. Copyright © 2016 Jacobs Institute of Women's Health. Published by Elsevier Inc. All rights reserved.

  6. Screening for prostatic cancer. Investigational models

    DEFF Research Database (Denmark)

    Iversen, P; Torp-Pedersen, S T

    1991-01-01

    Prostatic cancer has a long natural history and a significant preclinical period, during which the disease is detectable. Thus, this common malignancy in males fulfills some of the most important criteria for initiating screening programs. However, the still enigmatic epidemiology also includes...

  7. A System Dynamics Model of Serum Prostate-Specific Antigen Screening for Prostate Cancer.

    Science.gov (United States)

    Palma, Anton; Lounsbury, David W; Schlecht, Nicolas F; Agalliu, Ilir

    2016-02-01

    Since 2012, US guidelines have recommended against prostate-specific antigen (PSA) screening for prostate cancer. However, evidence of screening benefit from the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening trial and the European Randomized Study of Screening for Prostate Cancer has been inconsistent, due partly to differences in noncompliance and contamination. Using system dynamics modeling, we replicated the PLCO trial and extrapolated follow-up to 20 years. We then simulated 3 scenarios correcting for contamination in the PLCO control arm using Surveillance, Epidemiology, and End Results (SEER) incidence and survival data collected prior to the PSA screening era (scenario 1), SEER data collected during the PLCO trial period (1993-2001) (scenario 2), and data from the European trial's control arm (1991-2005) (scenario 3). In all scenarios, noncompliance was corrected using incidence and survival rates for men with screen-detected cancer in the PLCO screening arm. Scenarios 1 and 3 showed a benefit of PSA screening, with relative risks of 0.62 (95% confidence interval: 0.53, 0.72) and 0.70 (95% confidence interval: 0.59, 0.83) for cancer-specific mortality after 20 years, respectively. In scenario 2, however, there was no benefit of screening. This simulation showed that after correcting for noncompliance and contamination, there is potential benefit of PSA screening in reducing prostate cancer mortality. It also demonstrates the utility of system dynamics modeling for synthesizing epidemiologic evidence to inform public policy. © The Author 2015. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  8. Do school physical activity policies and programs have a role in decreasing multiple screen time behaviours among youth?

    Science.gov (United States)

    Katapally, Tarun R; Laxer, Rachel E; Qian, Wei; Leatherdale, Scott T

    2018-05-01

    Screen time in youth has been associated with a wide range of poor health outcomes. Evidence indicates the need to develop physical activity (PA) school policies and programs that are aimed at decreasing youth screen time behaviours. This study aims to understand the association between PA policies and programs embedded into the functioning of 89 schools across two provinces in Canada and multiple screen time behaviours. As part of the COMPASS Study, a total of 44,861 youth aged between 13 and 18years and belonging to 89 schools in two Canadian provinces completed a validated questionnaire for health behaviours and outcomes data. PA policies and programs were measured using the School Policies and Practices Questionnaire, completed by the relevant school administrator. Participation in before-school, noon hour, or after-school intramural programs, participation in varsity sports, and access to indoor areas of PA during non-instructional time, was associated with significantly lower multiple screen time behaviours across both provinces. With exposure to multiple electronic and digital devices only predicted to increase among youth in the future, there is a need to conceptualize and integrate school-based screen time reducing PA policies and programs into the regular functioning of the schools. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Screening fifth forces in k-essence and DBI models

    Energy Technology Data Exchange (ETDEWEB)

    Brax, Philippe [Institut de Physique Théorique, CEA, IPhT, CNRS, URA2306, F-91191 Gif-sur-Yvette cédex (France); Burrage, Clare [School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD (United Kingdom); Davis, Anne-Christine, E-mail: Philippe.Brax@cea.fr, E-mail: Clare.Burrage@nottingham.ac.uk, E-mail: A.C.Davis@damtp.cam.ac.uk [Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, Cambridge CB3 0WA (United Kingdom)

    2013-01-01

    New fifth forces have not yet been detected in the laboratory or in the solar system, hence it is typically difficult to introduce new light scalar fields that would mediate such forces. In recent years it has been shown that a number of non-linear scalar field theories allow for a dynamical mechanism, such as the Vainshtein and chameleon ones, that suppresses the strength of the scalar fifth force in experimental environments. This is known as screening, however it is unclear how common screening is within non-linear scalar field theories. k-essence models are commonly studied examples of non-linear models, with DBI as the best motivated example, and so we ask whether these non-linearities are able to screen a scalar fifth force. We find that a Vainshtein-like screening mechanism exists for such models although with limited applicability. For instance, we cannot find a screening mechanism for DBI models. On the other hand, we construct a large class of k-essence models which lead to the acceleration of the Universe in the recent past for which the fifth force mediated by the scalar can be screened.

  10. Simulation models in population breast cancer screening : A systematic review

    NARCIS (Netherlands)

    Koleva-Kolarova, Rositsa G; Zhan, Zhuozhao; Greuter, Marcel J W; Feenstra, Talitha L; De Bock, Geertruida H

    The aim of this review was to critically evaluate published simulation models for breast cancer screening of the general population and provide a direction for future modeling. A systematic literature search was performed to identify simulation models with more than one application. A framework for

  11. HYDROCARBON SPILL SCREENING MODEL (HSSM) VOLUME 1: USER'S GUIDE

    Science.gov (United States)

    This users guide describes the Hydrocarbon Spill Screening Model (HSSM). The model is intended for simulation of subsurface releases of light nonaqueous phase liquids (LNAPLs). The model consists of separate modules for LNAPL flow through the vadose zone, spreading in the capil...

  12. Information Security Policy Modeling for Network Security Systems

    Directory of Open Access Journals (Sweden)

    Dmitry Sergeevich Chernyavskiy

    2014-12-01

    Full Text Available Policy management for network security systems (NSSs is one of the most topical issues of network security management. Incorrect configurations of NSSs lead to system outages and appearance of vulnerabilities. Moreover, policy management process is a time-consuming task, which includes significant amount of manual work. These factors reduce efficiency of NSSs’ utilization. The paper discusses peculiarities of policy management process and existing approaches to policy modeling, presents a model aimed to formalize policies for NSSs independently on NSSs’ platforms and select the most effective NSSs for implementation of the policies.

  13. Item Screening in Graphical Loglinear Rasch Models

    DEFF Research Database (Denmark)

    Kreiner, Svend; Christensen, Karl Bang

    2011-01-01

    In behavioural sciences, local dependence and DIF are common, and purification procedures that eliminate items with these weaknesses often result in short scales with poor reliability. Graphical loglinear Rasch models (Kreiner & Christensen, in Statistical Methods for Quality of Life Studies, ed....... by M. Mesbah, F.C. Cole & M.T. Lee, Kluwer Academic, pp. 187–203, 2002) where uniform DIF and uniform local dependence are permitted solve this dilemma by modelling the local dependence and DIF. Identifying loglinear Rasch models by a stepwise model search is often very time consuming, since...... the initial item analysis may disclose a great deal of spurious and misleading evidence of DIF and local dependence that has to disposed of during the modelling procedure. Like graphical models, graphical loglinear Rasch models possess Markov properties that are useful during the statistical analysis...

  14. The cost-effectiveness of neonatal screening for Cystic Fibrosis: an analysis of alternative scenarios using a decision model

    Directory of Open Access Journals (Sweden)

    Tu Karen

    2005-08-01

    Full Text Available Abstract Background The use of neonatal screening for cystic fibrosis is widely debated in the United Kingdom and elsewhere, but the evidence available to inform policy is limited. This paper explores the cost-effectiveness of adding screening for cystic fibrosis to an existing routine neonatal screening programme for congenital hypothyroidism and phenylketonuria, under alternative scenarios and assumptions. Methods The study is based on a decision model comparing screening to no screening in terms of a number of outcome measures, including diagnosis of cystic fibrosis, life-time treatment costs, life years and QALYs gained. The setting is a hypothetical UK health region without an existing neonatal screening programme for cystic fibrosis. Results Under initial assumptions, neonatal screening (using an immunoreactive trypsin/DNA two stage screening protocol costs £5,387 per infant diagnosed, or £1.83 per infant screened (1998 costs. Neonatal screening for cystic fibrosis produces an incremental cost-effectiveness of £6,864 per QALY gained, in our base case scenario (an assumed benefit of a 6 month delay in the emergence of symptoms. A difference of 11 months or more in the emergence of symptoms (and mean survival means neonatal screening is both less costly and produces better outcomes than no screening. Conclusion Neonatal screening is expensive as a method of diagnosis. Neonatal screening may be a cost-effective intervention if the hypothesised delays in the onset of symptoms are confirmed. Implementing both antenatal and neonatal screening would undermine potential economic benefits, since a reduction in the birth incidence of cystic fibrosis would reduce the cost-effectiveness of neonatal screening.

  15. Affective Policy Performance Evaluation Model: A Case of an International Trade Policy Implementation

    Directory of Open Access Journals (Sweden)

    Inwon Kang

    2018-01-01

    Full Text Available Firms often superficially adopt policies because of governmental rules and regulations, so as to avoid penalties or to gain benefits. However, the evaluation and characterization of those kinds of adoptions as policy performance distorts the true level of policy performance: social sustainability. This study proposes an affective policy performance evaluation model. The attitudes of employees toward adopting a policy are characterized into genuine and superficial compliance. Their behaviors are explained through voluntary and opportunistic adoptions. In order to validate the proposed model, a survey was conducted on an international trade policy target group (n = 216 for the Strategic Trade Control System (STCS, in order to understand their attitudes toward adopting the policy. The survey data was analyzed by a structural equation modeling method. The measures of the factors in the proposed model are adopted and modified from existing studies. The most effective resources of policy implementation on the firms’ genuine and superficial compliance and ultimately on the firms’ voluntary policy adoption are revealed through the analysis. Based on the results, this study presents a strategy for allocating and managing policy implementation resources to exclusively encourage firms’ trade policy adoptions.

  16. Policy Analysis Screening System (PASS) demonstration: sample queries and terminal instructions

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-10-16

    This document contains the input and output for the Policy Analysis Screening System (PASS) demonstration. This demonstration is stored on a portable disk at the Environmental Impacts Division. Sample queries presented here include: (1) how to use PASS; (2) estimated 1995 energy consumption from Mid-Range Energy-Forecasting System (MEFS) data base; (3) pollution projections from Strategic Environmental Assessment System (SEAS) data base; (4) diesel auto regulations; (5) diesel auto health effects; (6) oil shale health and safety measures; (7) water pollution effects of SRC; (8) acid rainfall from Energy Environmental Statistics (EES) data base; 1990 EIA electric generation by fuel type; sulfate concentrations by Federal region; forecast of 1995 SO/sub 2/ emissions in Region III; and estimated electrical generating capacity in California to 1990. The file name for each query is included.

  17. In Vivo RNAi-Based Screens: Studies in Model Organisms

    Directory of Open Access Journals (Sweden)

    Miki Yamamoto-Hino

    2013-11-01

    Full Text Available RNA interference (RNAi is a technique widely used for gene silencing in organisms and cultured cells, and depends on sequence homology between double-stranded RNA (dsRNA and target mRNA molecules. Numerous cell-based genome-wide screens have successfully identified novel genes involved in various biological processes, including signal transduction, cell viability/death, and cell morphology. However, cell-based screens cannot address cellular processes such as development, behavior, and immunity. Drosophila and Caenorhabditis elegans are two model organisms whose whole bodies and individual body parts have been subjected to RNAi-based genome-wide screening. Moreover, Drosophila RNAi allows the manipulation of gene function in a spatiotemporal manner when it is implemented using the Gal4/UAS system. Using this inducible RNAi technique, various large-scale screens have been performed in Drosophila, demonstrating that the method is straightforward and valuable. However, accumulated results reveal that the results of RNAi-based screens have relatively high levels of error, such as false positives and negatives. Here, we review in vivo RNAi screens in Drosophila and the methods that could be used to remove ambiguity from screening results.

  18. Simulation Model Development for Mail Screening Process

    National Research Council Canada - National Science Library

    Vargo, Trish; Marvin, Freeman; Kooistra, Scott

    2005-01-01

    STUDY OBJECTIVE: Provide decision analysis support to the Homeland Defense Business Unit, Special Projects Team, in developing a simulation model to help determine the most effective way to eliminate backlog...

  19. Effects of changes in prenatal aneuploidy screening policies in an integrated health care system.

    Science.gov (United States)

    Norton, Mary E; Nakagawa, Sanae; Norem, Carol; Gregorich, Steven E; Kuppermann, Miriam

    2013-02-01

    To estimate changes in rates of prenatal testing for aneuploidy over a 5-year period in a large integrated health care system. Data from the Kaiser Permanente Northern California cytogenetics laboratory and Regional Prenatal Screening Program were used to estimate rates of prenatal aneuploidy screening and diagnostic testing in females of all ages during 2006-2010. We estimated the number of chromosome abnormalities detected and the proportion of abnormal cytogenetic results. Dichotomous variables were compared using χ tests. Rates of use and aneuploidy detection rates were compared for trend using a linear repeated-measures model. Annual deliveries decreased during this period, from 36,276 to 34,314, whereas births to women aged 35 years or older increased from 21.8% to 22.7% (P=.004). The rate of aneuploidy screening decreased minimally from 76.1% to 75.4% (P=.04). Among women 35 years or older, the rate of screening increased from 53.1% in 2006 to 63.7% in 2010 (P<.001), whereas the percentage having diagnostic testing decreased from 40.9% to 26.8% (P<.001). Among women younger than 35 years old, the rate of screening decreased from 82.5% in 2006 to 78.9% in 2010 and the rate of diagnostic testing decreased from 4.1% to 2.8% (P<.001). Abnormal diagnostic test results increased from 5.9% to 8.2% (P<.001); the number of chromosome abnormalities identified overall was 7.2 per 1,000 births in 2006 and 6.7 per 1,000 births in 2010 (P=.43). Offering comprehensive aneuploidy testing options to all pregnant women in an integrated health care system resulted in lower use and higher yield of diagnostic testing. II.

  20. Evaluating Energy Efficiency Policies with Energy-Economy Models

    Energy Technology Data Exchange (ETDEWEB)

    Mundaca, Luis; Neij, Lena; Worrell, Ernst; McNeil, Michael A.

    2010-08-01

    The growing complexities of energy systems, environmental problems and technology markets are driving and testing most energy-economy models to their limits. To further advance bottom-up models from a multidisciplinary energy efficiency policy evaluation perspective, we review and critically analyse bottom-up energy-economy models and corresponding evaluation studies on energy efficiency policies to induce technological change. We use the household sector as a case study. Our analysis focuses on decision frameworks for technology choice, type of evaluation being carried out, treatment of market and behavioural failures, evaluated policy instruments, and key determinants used to mimic policy instruments. Although the review confirms criticism related to energy-economy models (e.g. unrealistic representation of decision-making by consumers when choosing technologies), they provide valuable guidance for policy evaluation related to energy efficiency. Different areas to further advance models remain open, particularly related to modelling issues, techno-economic and environmental aspects, behavioural determinants, and policy considerations.

  1. A QSAR Model for Thyroperoxidase Inhibition and Screening ...

    Science.gov (United States)

    Thyroid hormones (THs) are critical modulators of a wide range of biological processes from neurodevelopment to metabolism. Well regulated levels of THs are critical during development and even moderate changes in maternal or fetal TH levels produce irreversible neurological deficits in children. The enzyme thyroperoxidase (TPO) plays a key role in the synthesis of THs. Inhibition of TPO by xenobiotics leads to decreased TH synthesis and, depending on the degree of synthesis inhibition, may result in adverse developmental outcomes. Recently, a high-throughput screening assay for TPO inhibition (AUR-TPO) was developed and used to screen the ToxCast Phase I and II chemicals. In the present study, we used the results from the AUR-TPO screening to develop a Quantitative Structure-Activity Relationship (QSAR) model for TPO inhibition in Leadscope®. The training set consisted of 898 discrete organic chemicals: 134 positive and 764 negative for TPO inhibition. A 10 times two-fold 50% cross-validation of the model was performed, yielding a balanced accuracy of 78.7% within its defined applicability domain. More recently, an additional ~800 chemicals from the US EPA Endocrine Disruption Screening Program (EDSP21) were screened using the AUR-TPO assay. This data was used for external validation of the QSAR model, demonstrating a balanced accuracy of 85.7% within its applicability domain. Overall, the cross- and external validations indicate a model with a high predictiv

  2. Simulation models in population breast cancer screening: A systematic review.

    Science.gov (United States)

    Koleva-Kolarova, Rositsa G; Zhan, Zhuozhao; Greuter, Marcel J W; Feenstra, Talitha L; De Bock, Geertruida H

    2015-08-01

    The aim of this review was to critically evaluate published simulation models for breast cancer screening of the general population and provide a direction for future modeling. A systematic literature search was performed to identify simulation models with more than one application. A framework for qualitative assessment which incorporated model type; input parameters; modeling approach, transparency of input data sources/assumptions, sensitivity analyses and risk of bias; validation, and outcomes was developed. Predicted mortality reduction (MR) and cost-effectiveness (CE) were compared to estimates from meta-analyses of randomized control trials (RCTs) and acceptability thresholds. Seven original simulation models were distinguished, all sharing common input parameters. The modeling approach was based on tumor progression (except one model) with internal and cross validation of the resulting models, but without any external validation. Differences in lead times for invasive or non-invasive tumors, and the option for cancers not to progress were not explicitly modeled. The models tended to overestimate the MR (11-24%) due to screening as compared to optimal RCTs 10% (95% CI - 2-21%) MR. Only recently, potential harms due to regular breast cancer screening were reported. Most scenarios resulted in acceptable cost-effectiveness estimates given current thresholds. The selected models have been repeatedly applied in various settings to inform decision making and the critical analysis revealed high risk of bias in their outcomes. Given the importance of the models, there is a need for externally validated models which use systematical evidence for input data to allow for more critical evaluation of breast cancer screening. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Association of US State Implementation of Newborn Screening Policies for Critical Congenital Heart Disease With Early Infant Cardiac Deaths.

    Science.gov (United States)

    Abouk, Rahi; Grosse, Scott D; Ailes, Elizabeth C; Oster, Matthew E

    2017-12-05

    In 2011, critical congenital heart disease was added to the US Recommended Uniform Screening Panel for newborns, but whether state implementation of screening policies has been associated with infant death rates is unknown. To assess whether there was an association between implementation of state newborn screening policies for critical congenital heart disease and infant death rates. Observational study with group-level analyses. A difference-in-differences analysis was conducted using the National Center for Health Statistics' period linked birth/infant death data set files for 2007-2013 for 26 546 503 US births through June 30, 2013, aggregated by month and state of birth. State policies were classified as mandatory or nonmandatory (including voluntary policies and mandates that were not yet implemented). As of June 1, 2013, 8 states had implemented mandatory screening policies, 5 states had voluntary screening policies, and 9 states had adopted but not yet implemented mandates. Numbers of early infant deaths (between 24 hours and 6 months of age) coded for critical congenital heart disease or other/unspecified congenital cardiac causes for each state-month birth cohort. Between 2007 and 2013, there were 2734 deaths due to critical congenital heart disease and 3967 deaths due to other/unspecified causes. Critical congenital heart disease death rates in states with mandatory screening policies were 8.0 (95% CI, 5.4-10.6) per 100 000 births (n = 37) in 2007 and 6.4 (95% CI, 2.9-9.9) per 100 000 births (n = 13) in 2013 (for births by the end of July); for other/unspecified cardiac causes, death rates were 11.7 (95% CI, 8.6-14.8) per 100 000 births in 2007 (n = 54) and 10.3 (95% CI, 5.9-14.8) per 100 000 births (n = 21) in 2013. Early infant deaths from critical congenital heart disease through December 31, 2013, decreased by 33.4% (95% CI, 10.6%-50.3%), with an absolute decline of 3.9 (95% CI, 3.6-4.1) deaths per 100 000 births after

  4. Including values in evidence-based policy making for breast screening: An empirically grounded tool to assist expert decision makers.

    Science.gov (United States)

    Parker, Lisa

    2017-07-01

    Values are an important part of evidence-based decision making for health policy: they guide the type of evidence that is collected, how it is interpreted, and how important the conclusions are considered to be. Experts in breast screening (including clinicians, researchers, consumer advocates and senior administrators) hold differing values in relation to what is important in breast screening policy and practice, and committees may find it difficult to incorporate the complexity and variety of values into policy decisions. The decision making tool provided here is intended to assist with this process. The tool is modified from more general frameworks that are intended to assist with ethical decision making in public health, and informed by data drawn from previous empirical studies on values amongst Australian breast screening experts. It provides a structured format for breast screening committees to consider and discuss the values of themselves and others, suggests relevant topics for further inquiry and highlights areas of need for future research into the values of the public. It enables committees to publicly explain and justify their decisions with reference to values, improving transparency and accountability. It is intended to act alongside practices that seek to accommodate the values of individual women in the informed decision making process for personal decision making about participation in breast screening. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Model-based inflation forecasts and monetary policy rules

    OpenAIRE

    Wouters, Raf; Dombrecht, Michel

    2000-01-01

    In this paper, the interaction between inflation and monetary policy rules is analysed within the framework of a dynamic general equilibrium model derived from optimising behaviour and rational expectations. Using model simulations, it is illustrated that the control of monetary policy over the inflation process is strongly dependent on the role of forward looking expectations in the price and wage setting process and on the credibility of monetary policy in the expectation formation process ...

  6. Maryland's Model Policy to Address Bullying, Harassment, or Intimidation

    Science.gov (United States)

    Maryland State Department of Education, 2016

    2016-01-01

    In accordance with the provisions of Section 7-424.1 of the Education Article of the Annotated Code of Maryland, the Maryland State Board of Education has developed and adopted a Model Policy to address bullying, harassment, or intimidation. This report presents the Model Policy, which is organized into the following eight points: (1) Prohibition…

  7. The role of public policies in reducing smoking: the Minnesota SimSmoke tobacco policy model.

    Science.gov (United States)

    Levy, David T; Boyle, Raymond G; Abrams, David B

    2012-11-01

    Following the landmark lawsuit and settlement with the tobacco industry, Minnesota pursued the implementation of stricter tobacco control policies, including tax increases, mass media campaigns, smokefree air laws, and cessation treatment policies. Modeling is used to examine policy effects on smoking prevalence and smoking-attributable deaths. To estimate the effect of tobacco control policies in Minnesota on smoking prevalence and smoking-attributable deaths using the SimSmoke simulation model. Minnesota data starting in 1993 are applied to SimSmoke, a simulation model used to examine the effect of tobacco control policies over time on smoking initiation and cessation. Upon validating the model against smoking prevalence, SimSmoke is used to distinguish the effect of policies implemented since 1993 on smoking prevalence. Using standard attribution methods, SimSmoke also estimates deaths averted as a result of the policies. SimSmoke predicts smoking prevalence accurately between 1993 and 2011. Since 1993, a relative reduction in smoking rates of 29% by 2011 and of 41% by 2041 can be attributed to tobacco control policies, mainly tax increases, smokefree air laws, media campaigns, and cessation treatment programs. Moreover, 48,000 smoking-attributable deaths will be averted by 2041. Minnesota SimSmoke demonstrates that tobacco control policies, especially taxes, have substantially reduced smoking prevalence and smoking-attributable deaths. Taxes, smokefree air laws, mass media, cessation treatment policies, and youth-access enforcement contributed to the decline in prevalence and deaths averted, with the strongest component being taxes. With stronger policies, for example, increasing cigarette taxes to $4.00 per pack, Minnesota's smoking rate could be reduced by another 13%, and 7200 deaths could be averted by 2041. Copyright © 2012 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  8. Modelling inspection policies for building maintenance.

    Science.gov (United States)

    Christer, A H

    1982-08-01

    A method of assessing the potential of an inspection maintenance policy as opposed to an existing breakdown maintenance policy for a building complex is developed. The method is based upon information likely to be available and specific subjective assessments which could be made available. Estimates of the expected number of defects identified at an inspection and the consequential cost saving are presented as functions of the inspection frequency.

  9. Multi-Tasking vs. Screening: A Model of Academic Tenure

    OpenAIRE

    Kou, Zonglai; Zhou, Min

    2009-01-01

    The paper develops a model of academic tenure based on multi-tasking and screening. A professor has two tasks, researching and teaching. We assume that researching performance is easy to measure but teaching performance is immeasurable. Then Holmtrom and Milgrom's (1991) classical muli-task principal-agent model implies that the only way for the the university to "incentivize" teaching activity is decreasing the incentive power to researching activity. This justifies the low-powered contract ...

  10. Cost Effective Community Based Dementia Screening: A Markov Model Simulation

    Directory of Open Access Journals (Sweden)

    Erin Saito

    2014-01-01

    Full Text Available Background. Given the dementia epidemic and the increasing cost of healthcare, there is a need to assess the economic benefit of community based dementia screening programs. Materials and Methods. Markov model simulations were generated using data obtained from a community based dementia screening program over a one-year period. The models simulated yearly costs of caring for patients based on clinical transitions beginning in pre dementia and extending for 10 years. Results. A total of 93 individuals (74 female, 19 male were screened for dementia and 12 meeting clinical criteria for either mild cognitive impairment (n=7 or dementia (n=5 were identified. Assuming early therapeutic intervention beginning during the year of dementia detection, Markov model simulations demonstrated 9.8% reduction in cost of dementia care over a ten-year simulation period, primarily through increased duration in mild stages and reduced time in more costly moderate and severe stages. Discussion. Community based dementia screening can reduce healthcare costs associated with caring for demented individuals through earlier detection and treatment, resulting in proportionately reduced time in more costly advanced stages.

  11. Moving communities toward policy change: APPEAL's 4-prong policy change model.

    Science.gov (United States)

    Tong, Elisa K; Lew, Rod

    2013-09-01

    Policy change is recognized for underlying much of the success of tobacco control. However, there is little evidence and attention on how Asian American and Native Hawaiian and Pacific Islander (AA and NHPI) communities may engage in policy change. Challenges for AA and NHPI communities include the racial/ethnic and geographic diversity, and tobacco data accurately representing the communities. Over the past decade, the Asian Pacific Partners for Empowerment, Advocacy and Leadership (APPEAL) has worked to develop and implement policy change for AA and NHPI communities. This article describes APPEAL's 4-prong policy change model, in the context of its overall strategic framework for policy change with communities that accounts for varying levels of readiness and leadership capacity, and targets four different levels of policy change (community, mainstream institution, legislative, and corporate). The health promotion implication of this framework for tobacco control policy engagement is for improving understanding of effective pathways to policy change, promoting innovative methods for policy analysis, and translating them into effective implementation and sustainability of policy initiatives. The APPEAL strategic framework can transcend into other communities and health topics that ultimately may contribute to the elimination of health disparities.

  12. Moving Communities Toward Policy Change: APPEAL’s 4-Prong Policy Change Model

    Science.gov (United States)

    Tong, Elisa K.; Lew, Rod

    2014-01-01

    Policy change is recognized for underlying much of the success of tobacco control. However, there is little evidence and attention on how Asian American and Native Hawaiian and Pacific Islander (AA and NHPI) communities may engage in policy change. Challenges for AA and NHPI communities include the racial/ethnic and geographic diversity, and tobacco data accurately representing the communities. Over the past decade, the Asian Pacific Partners for Empowerment, Advocacy and Leadership (APPEAL) has worked to develop and implement policy change for AA and NHPI communities. This article describes APPEAL’s 4-prong policy change model, in the context of its overall strategic framework for policy change with communities that accounts for varying levels of readiness and leadership capacity, and targets four different levels of policy change (community, mainstream institution, legislative, and corporate). The health promotion implication of this framework for tobacco control policy engagement is for improving understanding of effective pathways to policy change, promoting innovative methods for policy analysis, and translating them into effective implementation and sustainability of policy initiatives. The APPEAL strategic framework can transcend into other communities and health topics that ultimately may contribute to the elimination of health disparities. PMID:23707962

  13. Towards policy relevant environmental modeling: contextual validity and pragmatic models

    Science.gov (United States)

    Miles, Scott B.

    2000-01-01

    "What makes for a good model?" In various forms, this question is a question that, undoubtedly, many people, businesses, and institutions ponder with regards to their particular domain of modeling. One particular domain that is wrestling with this question is the multidisciplinary field of environmental modeling. Examples of environmental models range from models of contaminated ground water flow to the economic impact of natural disasters, such as earthquakes. One of the distinguishing claims of the field is the relevancy of environmental modeling to policy and environment-related decision-making in general. A pervasive view by both scientists and decision-makers is that a "good" model is one that is an accurate predictor. Thus, determining whether a model is "accurate" or "correct" is done by comparing model output to empirical observations. The expected outcome of this process, usually referred to as "validation" or "ground truthing," is a stamp on the model in question of "valid" or "not valid" that serves to indicate whether or not the model will be reliable before it is put into service in a decision-making context. In this paper, I begin by elaborating on the prevailing view of model validation and why this view must change. Drawing from concepts coming out of the studies of science and technology, I go on to propose a contextual view of validity that can overcome the problems associated with "ground truthing" models as an indicator of model goodness. The problem of how we talk about and determine model validity has much to do about how we perceive the utility of environmental models. In the remainder of the paper, I argue that we should adopt ideas of pragmatism in judging what makes for a good model and, in turn, developing good models. From such a perspective of model goodness, good environmental models should facilitate communication, convey—not bury or "eliminate"—uncertainties, and, thus, afford the active building of consensus decisions, instead

  14. Policy modeling for energy efficiency improvement in US industry

    International Nuclear Information System (INIS)

    Worrell, Ernst; Price, Lynn; Ruth, Michael

    2001-01-01

    We are at the beginning of a process of evaluating and modeling the contribution of policies to improve energy efficiency. Three recent policy studies trying to assess the impact of energy efficiency policies in the United States are reviewed. The studies represent an important step in the analysis of climate change mitigation strategies. All studies model the estimated policy impact, rather than the policy itself. Often the policy impacts are based on assumptions, as the effects of a policy are not certain. Most models only incorporate economic (or price) tools, which recent studies have proven to be insufficient to estimate the impacts, costs and benefits of mitigation strategies. The reviewed studies are a first effort to capture the effects of non-price policies. The studies contribute to a better understanding of the role of policies in improving energy efficiency and mitigating climate change. All policy scenarios results in substantial energy savings compared to the baseline scenario used, as well as substantial net benefits to the U.S. economy

  15. Modeling human papillomavirus and cervical cancer in the United States for analyses of screening and vaccination

    Directory of Open Access Journals (Sweden)

    Ortendahl Jesse

    2007-10-01

    Full Text Available Abstract Background To provide quantitative insight into current U.S. policy choices for cervical cancer prevention, we developed a model of human papillomavirus (HPV and cervical cancer, explicitly incorporating uncertainty about the natural history of disease. Methods We developed a stochastic microsimulation of cervical cancer that distinguishes different HPV types by their incidence, clearance, persistence, and progression. Input parameter sets were sampled randomly from uniform distributions, and simulations undertaken with each set. Through systematic reviews and formal data synthesis, we established multiple epidemiologic targets for model calibration, including age-specific prevalence of HPV by type, age-specific prevalence of cervical intraepithelial neoplasia (CIN, HPV type distribution within CIN and cancer, and age-specific cancer incidence. For each set of sampled input parameters, likelihood-based goodness-of-fit (GOF scores were computed based on comparisons between model-predicted outcomes and calibration targets. Using 50 randomly resampled, good-fitting parameter sets, we assessed the external consistency and face validity of the model, comparing predicted screening outcomes to independent data. To illustrate the advantage of this approach in reflecting parameter uncertainty, we used the 50 sets to project the distribution of health outcomes in U.S. women under different cervical cancer prevention strategies. Results Approximately 200 good-fitting parameter sets were identified from 1,000,000 simulated sets. Modeled screening outcomes were externally consistent with results from multiple independent data sources. Based on 50 good-fitting parameter sets, the expected reductions in lifetime risk of cancer with annual or biennial screening were 76% (range across 50 sets: 69–82% and 69% (60–77%, respectively. The reduction from vaccination alone was 75%, although it ranged from 60% to 88%, reflecting considerable parameter

  16. Unifying screening processes within the PROSPR consortium: a conceptual model for breast, cervical, and colorectal cancer screening.

    Science.gov (United States)

    Beaber, Elisabeth F; Kim, Jane J; Schapira, Marilyn M; Tosteson, Anna N A; Zauber, Ann G; Geiger, Ann M; Kamineni, Aruna; Weaver, Donald L; Tiro, Jasmin A

    2015-06-01

    General frameworks of the cancer screening process are available, but none directly compare the process in detail across different organ sites. This limits the ability of medical and public health professionals to develop and evaluate coordinated screening programs that apply resources and population management strategies available for one cancer site to other sites. We present a trans-organ conceptual model that incorporates a single screening episode for breast, cervical, and colorectal cancers into a unified framework based on clinical guidelines and protocols; the model concepts could be expanded to other organ sites. The model covers four types of care in the screening process: risk assessment, detection, diagnosis, and treatment. Interfaces between different provider teams (eg, primary care and specialty care), including communication and transfer of responsibility, may occur when transitioning between types of care. Our model highlights across each organ site similarities and differences in steps, interfaces, and transitions in the screening process and documents the conclusion of a screening episode. This model was developed within the National Cancer Institute-funded consortium Population-based Research Optimizing Screening through Personalized Regimens (PROSPR). PROSPR aims to optimize the screening process for breast, cervical, and colorectal cancer and includes seven research centers and a statistical coordinating center. Given current health care reform initiatives in the United States, this conceptual model can facilitate the development of comprehensive quality metrics for cancer screening and promote trans-organ comparative cancer screening research. PROSPR findings will support the design of interventions that improve screening outcomes across multiple cancer sites. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  17. Resilience of a FIT screening programme against screening fatigue: a modelling study

    NARCIS (Netherlands)

    Greuter, Marjolein J. E.; Berkhof, Johannes; Canfell, Karen; Lew, Jie-Bin; Dekker, Evelien; Coupé, Veerle M. H.

    2016-01-01

    Repeated participation is important in faecal immunochemical testing (FIT) screening for colorectal cancer (CRC). However, a large number of screening invitations over time may lead to screening fatigue and consequently, decreased participation rates. We evaluated the impact of screening fatigue on

  18. An evaluation model for low carbon island policy: The case of Taiwan's green transportation policy

    International Nuclear Information System (INIS)

    Trappey, Amy J.C.; Trappey, Charles; Hsiao, C.T.; Ou, Jerry J.R.; Li, S.J.; Chen, Kevin W.P.

    2012-01-01

    Conserving energy and reducing carbon emissions have become the common responsibility of the international community. During the year 2010, the Taiwan government planned a four-year project budgeted at 300 million US dollars, called “The Penghu Low Carbon Island Development Project.” The policy objective is to use Penghu Island (population 85,000) as a test platform to evaluate new ways to conserve energy and reduce carbon emissions before attempting to replicate the policies on Taiwan Island. For Taiwan, a zero carbon island green transportation policy will regulate the total number of electric scooters, the total number of gasoline motorcycles, influence government subsidy incentives, and create the need for new motorcycle license issuing and control. These factors interact with each other to form a complex and dynamic system that impacts policy as well as the current way of life. In this study, a system dynamics approach is designed to construct a model for evaluating the green transportation policy on Penghu Island. Simulations are conducted to model green transportation system behavior and related policy effects in a smaller, controlled environment before creating policies for Taiwan Island that will impact the lives of over 23 million people. - Highlights: ► Provides an overview of Taiwan's Penghu Low Carbon Island Development Project. ► Develops a systems dynamics approach for green transportation policy assessment. ► Provides causal analysis of social, economic, and environmental factors. ► Demonstrates that the proposed policy cannot meet the CO 2 reduction goals. ► Alternative policies can be evaluated using the proposed approach.

  19. Policy harmonized approach for the EU agricultural sector modelling

    Directory of Open Access Journals (Sweden)

    G. SALPUTRA

    2008-12-01

    Full Text Available Policy harmonized (PH approach allows for the quantitative assessment of the impact of various elements of EU CAP direct support schemes, where the production effects of direct payments are accounted through reaction prices formed by producer price and policy price add-ons. Using the AGMEMOD model the impacts of two possible EU agricultural policy scenarios upon beef production have been analysed – full decoupling with a switch from historical to regional Single Payment scheme or alternatively with re-distribution of country direct payment envelopes via introduction of EU-wide flat area payment. The PH approach, by systematizing and harmonizing the management and use of policy data, ensures that projected differential policy impacts arising from changes in common EU policies reflect the likely actual differential impact as opposed to differences in how “common” policies are implemented within analytical models. In the second section of the paper the AGMEMOD model’s structure is explained. The policy harmonized evaluation method is presented in the third section. Results from an application of the PH approach are presented and discussed in the paper’s penultimate section, while section 5 concludes.;

  20. Adolescent idiopathic scoliosis screening for school, community, and clinical health promotion practice utilizing the PRECEDE-PROCEED model

    Directory of Open Access Journals (Sweden)

    Wyatt Lawrence A

    2005-11-01

    Full Text Available Abstract Background Screening for adolescent idiopathic scoliosis (AIS is a commonly performed procedure for school children during the high risk years. The PRECEDE-PROCEDE (PP model is a health promotion planning model that has not been utilized for the clinical diagnosis of AIS. The purpose of this research is to study AIS in the school age population using the PP model and its relevance for community, school, and clinical health promotion. Methods MEDLINE was utilized to locate AIS data. Studies were screened for relevance and applicability under the auspices of the PP model. Where data was unavailable, expert opinion was utilized based on consensus. Results The social assessment of quality of life is limited with few studies approaching the long-term effects of AIS. Epidemiologically, AIS is the most common form of scoliosis and leading orthopedic problem in children. Behavioral/environmental studies focus on discovering etiologic relationships yet this data is confounded because AIS is not a behavioral. Illness and parenting health behaviors can be appreciated. The educational diagnosis is confounded because AIS is an orthopedic disorder and not behavioral. The administration/policy diagnosis is hindered in that scoliosis screening programs are not considered cost-effective. Policies are determined in some schools because 26 states mandate school scoliosis screening. There exists potential error with the Adam's test. The most widely used measure in the PP model, the Health Belief Model, has not been utilized in any AIS research. Conclusion The PP model is a useful tool for a comprehensive study of a particular health concern. This research showed where gaps in AIS research exist suggesting that there may be problems to the implementation of school screening. Until research disparities are filled, implementation of AIS screening by school, community, and clinical health promotion will be compromised. Lack of data and perceived importance by

  1. A simultaneous equations model of fiscal policy interactions

    NARCIS (Netherlands)

    Allers, Maarten A.; Elhorst, J. Paul

    Existing studies of fiscal policy interactions are based on single equation (SE) models of either taxation or expenditures, without specifying the underlying social welfare function, without taking account of budget constraints and without allowing for cost differences between jurisdictions. Taking

  2. Scoring Models of Bank Credit Policy Management

    OpenAIRE

    Aida Hanic; Emina Zunic; Adnan Dzelihodzic

    2013-01-01

    The aim of this paper is to present how credit scoring models can be used in financial institutions, in this case in banks, in order to simplify credit lending. Unlike traditional models of credit analysis, scoring models provides valuation based on numerical score who represent clients’ possibility to fulfil their obligation. Using credit scoring models, bank can create a numerical snapshot of consumers risk profile. One of the most important characteristic of scoring models is objectivity w...

  3. Global climate change policies. An analysis of CDM policies with an adapted GTAP model

    International Nuclear Information System (INIS)

    Wang, Shunli

    2004-01-01

    In the context of the relationships between spatial-economic interaction and global warming just discussed, this study aims to analyze the Clean Development Mechanisms (CDM) policies from an economic point of view. The research question of this study is formulated as follows: What will be the impacts of clirnate change policies, in particular CDM policies, on the economic performance of (groups of) countries in our global economic system, taking spatial interaction and general equilibrium effects into account? The purpose of addressing the issue of economic performance for (groups of) countries in the economic system is not just to identify winners and losers from international treaties. Rather, winning or losing may even determine the implementation and willingness of individual countries to participate in international environmental treaties, as illustrated by the recent withdrawal of the US from the Kyoto Protocol. By analyzing the economic impacts of an international environmental treaty for individual (groups of) countries, the framework that will be used to analyze this research question may be useful to determine the attractiveness of some global environmental policies, both for the world as a whole and for individual (groups of) countries. The research question will be answered by dividing it into six subquestions: (1) What is the position of CDM policies in the broad context of climate policy regimes?; (2) How should the relationship between human behavior and the physical environment be ideally modeled from an economic perspective? (3) How should the spatial dimension be incorporated in this framework of interaction between the economic and ecological system?; (4) How can climate change issues be incorporated in general equilibrium models in general, and in GTAP-E (extension of the Global Trade Analysis Project) in particular?; (5) How can CDM policies be implemented in the GTAP-E model?; and (6) What are the impacts of these climate change policies on

  4. The French nuclear policy. A model for security policy in North-East Asia

    International Nuclear Information System (INIS)

    Choe, K.

    1998-01-01

    Between the end of the second world war and the collapse of the Berlin wall, the French diplomacy was based on the nuclear policy in a solid and coherent way. This nuclear policy was an 'incarnation' of the national security conception, allowing France to recover its political, military and economical rank on the international scene. The most important characteristic of the French nuclear policy concerns the commercialization of the nuclear energy which aims to ensuring the national security through the building up of a financial, technological and political 'reserve'. In front of the domination of the USA and USSR during the cold war era, NE Asia had a similar geostrategic configuration as Western Europe. It concerns in particular the massive application of nuclear energy for both military and industrial purposes. The bases of the security policy in this region refers to the real use of the nuclear weapon by the USA against Japan in 1945. The French nuclear policy may be considered as a model for the building of the security policy of NE Asia, in particular through the commercialization of the nuclear technology between the countries in concern. This nuclear approach would allow the countries of these region to change their present day national defense policy into an economical and military cooperation. (J.S.)

  5. Cardiff sciSCREEN: A model for using film screenings to engage publics in University research

    OpenAIRE

    Lewis, Jamie Thornton; Bisson, Susan; Swaden Lewis, Katie; Reyes-Galindo, Luis; Baldwin, Amy Joy

    2017-01-01

    Cardiff sciSCREEN is a public engagement programme that brings together local experts and publics to discuss issues raised by contemporary cinema. Since 2010, Cardiff sciSCREEN (short for science on screen) has exhibited more than 50 films alongside short talks and discussions that draw on a range of disciplinary perspectives to explore the broad repertoire of themes found within different film genres. The aim of Cardiff sciSCREEN is to increase the local community's access to university rese...

  6. Cervical cancer screening in Australia: modelled evaluation of the impact of changing the recommended interval from two to three years

    Directory of Open Access Journals (Sweden)

    Howard Kirsten

    2010-11-01

    Full Text Available Abstract Background The National Cervical Screening Program in Australia currently recommends that sexually active women between the ages of 18-70 years attend routine screening every 2 years. The publically funded National HPV Vaccination Program commenced in 2007, with catch-up in females aged 12-26 years conducted until 2009; and this may prompt consideration of whether the screening interval and other aspects of the organized screening program could be reviewed. The aim of the current evaluation was to assess the epidemiologic outcomes and cost implications of changing the recommended screening interval in Australia to 3 years. Methods We used a modelling approach to evaluate the effects of moving to a 3-yearly recommended screening interval. We used data from the Victorian Cervical Cytology Registry over the period 1997-2007 to model compliance with routine screening under current practice, and registry data from other countries with 3-yearly recommendations to inform assumptions about future screening behaviour under two alternative systems for screening organisation - retention of a reminder-based system (as in New Zealand, or a move to a call-and-recall system (as in England. Results A 3-yearly recommendation is predicted to be of similar effectiveness to the current 2-yearly recommendation, resulting in no substantial change to the total number of incident cervical cancer cases or cancer deaths, or to the estimated 0.68% average cumulative lifetime risk of cervical cancer in unvaccinated Australian women. However, a 3-yearly screening policy would be associated with decreases in the annual number of colposcopy and biopsy procedures performed (by 4-10% and decreases in the number of treatments for pre-invasive lesions (by 2-4%. The magnitude of the decrease in the number of diagnostic procedures and treatments would depend on the method of screening organization, with call-and-recall screening associated with the highest reductions. The

  7. Developing policy analytics for public health strategy and decisions-the Sheffield alcohol policy model framework.

    Science.gov (United States)

    Brennan, Alan; Meier, Petra; Purshouse, Robin; Rafia, Rachid; Meng, Yang; Hill-Macmanus, Daniel

    This paper sets out the development of a methodological framework for detailed evaluation of public health strategies for alcohol harm reduction to meet UK policy-makers needs. Alcohol is known to cause substantial harms, and controlling its affordability and availability are effective policy options. Analysis and synthesis of a variety of public and commercial data sources is needed to evaluate impact on consumers, health services, crime, employers and industry, so a sound evaluation of impact is important. We discuss the iterative process to engage with stakeholders, identify evidence/data and develop analytic approaches and produce a final model structure. We set out a series of steps in modelling impact including: classification and definition of population subgroups of interest, identification and definition of harms and outcomes for inclusion, classification of modifiable components of risk and their baseline values, specification of the baseline position on policy variables especially prices, estimating effects of changing policy variables on risk factors including price elasticities, quantifying risk functions relating risk factors to harms including 47 health conditions, crimes, absenteeism and unemployment, and monetary valuation. The most difficult model structuring decisions are described, as well as the final results framework used to provide decision support to national level policymakers in the UK. In the discussion we explore issues around the relationship between modelling and policy debates, valuation and scope, limitations of evidence/data, how the framework can be adapted to other countries and decisions. We reflect on the approach taken and outline ongoing plans for further development.

  8. Assessing The Policy Relevance of Regional Air Quality Models

    Science.gov (United States)

    Holloway, T.

    This work presents a framework for discussing the policy relevance of models, and regional air quality models in particular. We define four criteria: 1) The scientific status of the model; 2) Its ability to address primary environmental concerns; 3) The position of modeled environmental issues on the political agenda; and 4) The role of scientific input into the policy process. This framework is applied to current work simulating the transport of nitric acid in Asia with the ATMOS-N model, to past studies on air pollution transport in Europe with the EMEP model, and to future applications of the United States Environmental Protection Agency (US EPA) Models-3. The Lagrangian EMEP model provided critical input to the development of the 1994 Oslo and 1999 Gothenburg Protocols to the Convention on Long-Range Transbound- ary Air Pollution, as well as to the development of EU directives, via its role as a component of the RAINS integrated assessment model. Our work simulating reactive nitrogen in Asia follows the European example in part, with the choice of ATMOS-N, a regional Lagrangian model to calculate source-receptor relationships for the RAINS- Asia integrated assessment model. However, given differences between ATMOS-N and the EMEP model, as well as differences between the scientific and political cli- mates facing Europe ten years ago and Asia today, the role of these two models in the policy process is very different. We characterize the different aspects of policy relevance between these models using our framework, and consider how the current generation US EPA air quality model compares, in light of its Eulerian structure, dif- ferent objectives, and the policy context of the US.

  9. Applications of system dynamics modelling to support health policy.

    Science.gov (United States)

    Atkinson, Jo-An M; Wells, Robert; Page, Andrew; Dominello, Amanda; Haines, Mary; Wilson, Andrew

    2015-07-09

    The value of systems science modelling methods in the health sector is increasingly being recognised. Of particular promise is the potential of these methods to improve operational aspects of healthcare capacity and delivery, analyse policy options for health system reform and guide investments to address complex public health problems. Because it lends itself to a participatory approach, system dynamics modelling has been a particularly appealing method that aims to align stakeholder understanding of the underlying causes of a problem and achieve consensus for action. The aim of this review is to determine the effectiveness of system dynamics modelling for health policy, and explore the range and nature of its application. A systematic search was conducted to identify articles published up to April 2015 from the PubMed, Web of Knowledge, Embase, ScienceDirect and Google Scholar databases. The grey literature was also searched. Papers eligible for inclusion were those that described applications of system dynamics modelling to support health policy at any level of government. Six papers were identified, comprising eight case studies of the application of system dynamics modelling to support health policy. No analytic studies were found that examined the effectiveness of this type of modelling. Only three examples engaged multidisciplinary stakeholders in collective model building. Stakeholder participation in model building reportedly facilitated development of a common 'mental map' of the health problem, resulting in consensus about optimal policy strategy and garnering support for collaborative action. The paucity of relevant papers indicates that, although the volume of descriptive literature advocating the value of system dynamics modelling is considerable, its practical application to inform health policy making is yet to be routinely applied and rigorously evaluated. Advances in software are allowing the participatory model building approach to be extended to

  10. [Biomarker screening of rat pulmonary hypertension model by transcriptome sequencing].

    Science.gov (United States)

    Hu, F; Xie, L; Yu, L; Chen, J; Liu, H M

    2016-04-01

    To screen relative gene and pathway of rat severe pulmonary hypertension by transcriptome sequencing. Pulmonary hypertension animal model of SD rats was established by left lung resection and hypodermic injection of monocrotaline.Monocrotaline was injected subcutaneously one week after left lung resection.Eight rats at 1, 3, 5 weeks after the injection of monocrotaline respectively were named group M1, group M2 and group M3.Eight normal rats were assigned into control group (group C). The right lung tissue was used for transcriptome sequencing to screen the differentially expressed genes.KEGG pathway analysis was performed to screen the pathways with enriched differentially expressed genes. The animal model was established successfully.The pulmonary artery pressure was as follows: group C (28.6±3.0) mmHg(1 mmHg=0.133 kPa), group M1 (38.9±3.3) mmHg, group M2 (50.8±3.9) mmHg, group M3 (51.5±3.5) mmHg.The pressure elevated in group M1 compared with group C (P=0.007). The pressure in M2 and M3 elevated compared with M1(P=0.002 and Ppulmonary hypertension were epithelial specific receptor tyrosine kinase(Tie2) and thrombospondin-1(TSP-1). Tie2 was down-regulated (qpulmonary hypertension and up-regulated (qpulmonary hypertension.TSP-1 was up-regulated (qpulmonary hypertension and down-regulated (qpulmonary hypertension.In the stage of severe pulmonary hypertension, the differentially expressed genes were enriched mainly in the pathways of phosphatidylinostitol 3-kinase, focal adhesion kinase and extracellular matrix receptor interaction. The study provides transcriptome information of rat pulmonary hypertension model and normal rat.Possible mechanisms of pulmonary hypertension are found.These genes and pathways might be new precursor for the diagnosis and treatment of pulmonary hypertension.

  11. Development and weighting of a life cycle assessment screening model

    Science.gov (United States)

    Bates, Wayne E.; O'Shaughnessy, James; Johnson, Sharon A.; Sisson, Richard

    2004-02-01

    Nearly all life cycle assessment tools available today are high priced, comprehensive and quantitative models requiring a significant amount of data collection and data input. In addition, most of the available software packages require a great deal of training time to learn how to operate the model software. Even after this time investment, results are not guaranteed because of the number of estimations and assumptions often necessary to run the model. As a result, product development, design teams and environmental specialists need a simplified tool that will allow for the qualitative evaluation and "screening" of various design options. This paper presents the development and design of a generic, qualitative life cycle screening model and demonstrates its applicability and ease of use. The model uses qualitative environmental, health and safety factors, based on site or product-specific issues, to sensitize the overall results for a given set of conditions. The paper also evaluates the impact of different population input ranking values on model output. The final analysis is based on site or product-specific variables. The user can then evaluate various design changes and the apparent impact or improvement on the environment, health and safety, compliance cost and overall corporate liability. Major input parameters can be varied, and factors such as materials use, pollution prevention, waste minimization, worker safety, product life, environmental impacts, return of investment, and recycle are evaluated. The flexibility of the model format will be discussed in order to demonstrate the applicability and usefulness within nearly any industry sector. Finally, an example using audience input value scores will be compared to other population input results.

  12. Perspectives and Practices of Athletic Trainers and Team Physicians Implementing the 2010 NCAA Sickle Cell Trait Screening Policy.

    Science.gov (United States)

    McDonald, Mary Anne; Creary, Melissa S; Powell, Jill; Daley, Lori-Ann; Baker, Charlotte; Royal, Charmaine Dm

    2017-12-01

    Sickle cell trait (SCT) is usually benign. However, there are some conditions that may lead to SCT-related problems and put athletes with the trait at particular risk. In 2010 the National Collegiate Athletic Association (NCAA) issued a policy that required all Division I (DI) student-athletes to confirm their SCT status or sign a liability waiver to opt out of testing. Athletic trainers and team physicians play key roles in the policy implementation and we examined their perceptions and practices. Between December 2013 and March 2014 we interviewed 13 head athletic trainers and team physicians at NCAA Division I colleges and universities in North Carolina. We used an interview guide with open-ended questions covering knowledge of SCT, historical screening and education practices, current implementation, and policy benefits and challenges. Participants were knowledgeable about SCT and thought the policy was beneficial in providing SCT health information to and for student-athletes. Schools varied in provision of genetic counseling, offering the waiver, SCT tests administered, and other aspects. Challenges included: insufficient guidance from the NCAA; financial considerations; and misunderstanding of the relationships of race and ancestry to SCT risk. Athletic staff found the policy valuable, but felt it needs clarity and standardization.

  13. An oral multispecies biofilm model for high content screening applications.

    Directory of Open Access Journals (Sweden)

    Nadine Kommerein

    Full Text Available Peri-implantitis caused by multispecies biofilms is a major complication in dental implant treatment. The bacterial infection surrounding dental implants can lead to bone loss and, in turn, to implant failure. A promising strategy to prevent these common complications is the development of implant surfaces that inhibit biofilm development. A reproducible and easy-to-use biofilm model as a test system for large scale screening of new implant surfaces with putative antibacterial potency is therefore of major importance. In the present study, we developed a highly reproducible in vitro four-species biofilm model consisting of the highly relevant oral bacterial species Streptococcus oralis, Actinomyces naeslundii, Veillonella dispar and Porphyromonas gingivalis. The application of live/dead staining, quantitative real time PCR (qRT-PCR, scanning electron microscopy (SEM and urea-NaCl fluorescence in situ hybridization (urea-NaCl-FISH revealed that the four-species biofilm community is robust in terms of biovolume, live/dead distribution and individual species distribution over time. The biofilm community is dominated by S. oralis, followed by V. dispar, A. naeslundii and P. gingivalis. The percentage distribution in this model closely reflects the situation in early native plaques and is therefore well suited as an in vitro model test system. Furthermore, despite its nearly native composition, the multispecies model does not depend on nutrient additives, such as native human saliva or serum, and is an inexpensive, easy to handle and highly reproducible alternative to the available model systems. The 96-well plate format enables high content screening for optimized implant surfaces impeding biofilm formation or the testing of multiple antimicrobial treatment strategies to fight multispecies biofilm infections, both exemplary proven in the manuscript.

  14. Evaluating business models for microgrids: Interactions of technology and policy

    International Nuclear Information System (INIS)

    Hanna, Ryan; Ghonima, Mohamed; Kleissl, Jan; Tynan, George; Victor, David G.

    2017-01-01

    Policy makers are increasingly focused on strategies to decentralize the electricity grid. We analyze the business model for one mode of decentralization—microgrids—and quantify the economics for self-supply of electricity and thermal energy and explicitly resolve technological as well as policy variables. We offer a tool, based on the Distributed Energy Resources Customer Adoption Model (DER-CAM) modeling framework, that determines the cost-minimal capacity and operation of distributed energy resources in a microgrid, and apply it in southern California to three “iconic” microgrid types which represent typical commercial adopters: a large commercial building, critical infrastructure, and campus. We find that optimal investment leads to some deployment of renewables but that natural gas technologies underpin the most robust business cases—due in part to relatively cheap gas and high electricity rates. This finding contrasts sharply with most policy advocacy, which has focused on the potentials for decentralization of the grid to encourage deployment of renewables. Decentralization could radically reduce customer energy costs, but without the right policy framework it could create large numbers of small decentralized sources of gas-based carbon emissions that will be difficult to control if policy makers want to achieve deep cuts in greenhouse gas emissions. - Highlights: • We offer a modeling tool to study technology and policy variables for microgrids. • We construct comprehensive load profiles for three likely adopters of microgrids. • Investment in natural gas generators is key to enabling business models. • Solar PV and storage are optimal but as supplements to gas generation. • Business models are highly robust to sensitivity in technology and policy variables.

  15. A Screening-Level Hydroeconomic Model of South Florida Water Resources System

    Science.gov (United States)

    Mirchi, A.; Watkins, D. W., Jr.; Flaxman, M.; Wiesmann, D.

    2014-12-01

    South Florida's water resources management is characterized by system-wide tradeoffs associated with maintaining the ecological integrity of natural environments such as the Everglades while meeting the water demands of the agricultural sector and growing urban areas. As these tradeoffs become more pronounced due to pressures from climate change, sea level rise, and population growth, it will be increasingly challenging for policy makers and stakeholders to reach consensus on water resources management objectives and planning horizons. A hydroeconomic optimization model of south Florida's water resources system is developed to incorporate the value of water for preserving ecosystem services alongside water supplies to the Everglades Agricultural Area and urban areas. Results of this screening-level network flow model facilitate quantitative analysis and provide insights for long-term adaptive management strategies for the region's water resources.

  16. [Model concept of the health economic evaluation of low-dose CT lung cancer screening in Hungary].

    Science.gov (United States)

    Vokó, Zoltán; Barra, Magdolna; Molnár, Anett; Kerpel-Fronius, Anna; Bajzik, Gábor; Horváth, Ildikó; Moizs, Mariann; Nagy, Balázs

    2017-06-01

    Lung cancer is a rapidly progressing, often life-threatening disease that constitutes a huge societal burden. Because of the scarce resources of the Hungarian health care system, the cost-effectiveness of introducing low-dose computed tomography screening is a relevant health policy matter. The aim of this study is to design a model concept for assessing the cost-effectiveness of low-dose computed tomography lung cancer screening in Hungary, and to define the required steps for performing the analysis. A targeted literature review was conducted to identify and synthesize the evidence on efficacy and effectiveness of screening, and results were evaluated based on adaptability to Hungarian settings. We also summarized the available Hungarian scientific evidence and reconstructed the potential patient pathways. In accordance with these findings, we recommend to perform the full health-economic evaluation of low-dose computed tomography lung cancer screening using a complex model structure that consists of several sub-models and is capable to follow the population at risk on life-time horizon. The proposed cost-effectiveness model will be suitable to provide data for further analyses that support decision-making on introducing low-dose computed tomography lung cancer screening as public health program. Orv Hetil. 2017; 158(25): 963-975.

  17. THEORIES AND MODELS OF FISCAL POLICY

    OpenAIRE

    Alina Georgiana SOLOMON

    2013-01-01

    Within the paper “Theories and models of fiscal policy” we made a presentation of the main fiscal theories elaborated by the renowned representatives of the Physiocratic School, of the classic English School and last, but not least, the neoclassic approach of the aforementioned in the vision of Frank Ramsey and Arthur Laffer. The purpose of the paper is to highlight which was the contribution of the fiscal theories and models formulated by scholars and to what extent they contributed to devel...

  18. THE SHEFFIELD ALCOHOL POLICY MODEL - A MATHEMATICAL DESCRIPTION.

    Science.gov (United States)

    Brennan, Alan; Meier, Petra; Purshouse, Robin; Rafia, Rachid; Meng, Yang; Hill-Macmanus, Daniel; Angus, Colin; Holmes, John

    2014-09-30

    This methodology paper sets out a mathematical description of the Sheffield Alcohol Policy Model version 2.0, a model to evaluate public health strategies for alcohol harm reduction in the UK. Policies that can be appraised include a minimum price per unit of alcohol, restrictions on price discounting, and broader public health measures. The model estimates the impact on consumers, health services, crime, employers, retailers and government tax revenues. The synthesis of public and commercial data sources to inform the model structure is described. A detailed algebraic description of the model is provided. This involves quantifying baseline levels of alcohol purchasing and consumption by age and gender subgroups, estimating the impact of policies on consumption, for example, using evidence on price elasticities of demand for alcohol, quantification of risk functions relating alcohol consumption to harms including 47 health conditions, crimes, absenteeism and unemployment, and finally monetary valuation of the consequences. The results framework, shown for a minimum price per unit of alcohol, has been used to provide policy appraisals for the UK government policy-makers. In discussion and online appendix, we explore issues around valuation and scope, limitations of evidence/data, how the framework can be adapted to other countries and decisions, and ongoing plans for further development. © 2014 The Authors. Health Economics published by John Wiley & Sons Ltd. © 2014 The Authors. Health Economics published by John Wiley & Sons Ltd.

  19. Prioritizing Congenital Syphilis Control in South China: A Decision Analytic Model to Inform Policy Implementation

    Science.gov (United States)

    Tan, Nicholas X.; Rydzak, Chara; Yang, Li-Gang; Vickerman, Peter; Yang, Bin; Peeling, Rosanna W.; Hawkes, Sarah; Chen, Xiang-Sheng; Tucker, Joseph D.

    2013-01-01

    Background Syphilis is a major public health problem in many regions of China, with increases in congenital syphilis (CS) cases causing concern. The Chinese Ministry of Health recently announced a comprehensive 10-y national syphilis control plan focusing on averting CS. The decision analytic model presented here quantifies the impact of the planned strategies to determine whether they are likely to meet the goals laid out in the control plan. Methods and Findings Our model incorporated data on age-stratified fertility, female adult syphilis cases, and empirical syphilis transmission rates to estimate the number of CS cases associated with prenatal syphilis infection on a yearly basis. Guangdong Province was the focus of this analysis because of the availability of high-quality demographic and public health data. Each model outcome was simulated 1,000 times to incorporate uncertainty in model inputs. The model was validated using data from a CS intervention program among 477,656 women in China. Sensitivity analyses were performed to identify which variables are likely to be most influential in achieving Chinese and international policy goals. Increasing prenatal screening coverage was the single most effective strategy for reducing CS cases. An incremental increase in prenatal screening from the base case of 57% coverage to 95% coverage was associated with 106 (95% CI: 101, 111) CS cases averted per 100,000 live births (58% decrease). The policy strategies laid out in the national plan led to an outcome that fell short of the target, while a four-pronged comprehensive syphilis control strategy consisting of increased prenatal screening coverage, increased treatment completion, earlier prenatal screening, and improved syphilis test characteristics was associated with 157 (95% CI: 154, 160) CS cases averted per 100,000 live births (85% decrease). Conclusions The Chinese national plan provides a strong foundation for syphilis control, but more comprehensive measures

  20. Mathematical modelling informs HIV prevention policy in China ...

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

    2016-04-27

    Apr 27, 2016 ... IDRC-funded research is using mathematical modelling to influence local and national policies in China to reduce HIV transmission. Treatment as prevention Earlier research conducted under Modelling and controlling infectious diseases project showed that providing antiretroviral therapy (ART) to ...

  1. Risk prediction models for selection of lung cancer screening candidates: A retrospective validation study.

    Directory of Open Access Journals (Sweden)

    Kevin Ten Haaf

    2017-04-01

    slightly higher specificity for some models. The PLCOm2012, Bach, and Two-Stage Clonal Expansion incidence models had the best overall performance, with AUCs >0.68 in the NLST and >0.77 in the PLCO. These three models had the highest sensitivity and specificity for predicting 6-y lung cancer incidence in the PLCO chest radiography arm, with sensitivities >79.8% and specificities >62.3%. In contrast, the NLST eligibility criteria yielded a sensitivity of 71.4% and a specificity of 62.2%. Limitations of this study include the lack of identification of optimal risk thresholds, as this requires additional information on the long-term benefits (e.g., life-years gained and mortality reduction and harms (e.g., overdiagnosis of risk-based screening strategies using these models. In addition, information on some predictor variables included in the risk prediction models was not available.Selection of individuals for lung cancer screening using individual risk is superior to selection criteria based on age and pack-years alone. The benefits, harms, and feasibility of implementing lung cancer screening policies based on risk prediction models should be assessed and compared with those of current recommendations.

  2. Risk prediction models for selection of lung cancer screening candidates: A retrospective validation study.

    Science.gov (United States)

    Ten Haaf, Kevin; Jeon, Jihyoun; Tammemägi, Martin C; Han, Summer S; Kong, Chung Yin; Plevritis, Sylvia K; Feuer, Eric J; de Koning, Harry J; Steyerberg, Ewout W; Meza, Rafael

    2017-04-01

    higher specificity for some models. The PLCOm2012, Bach, and Two-Stage Clonal Expansion incidence models had the best overall performance, with AUCs >0.68 in the NLST and >0.77 in the PLCO. These three models had the highest sensitivity and specificity for predicting 6-y lung cancer incidence in the PLCO chest radiography arm, with sensitivities >79.8% and specificities >62.3%. In contrast, the NLST eligibility criteria yielded a sensitivity of 71.4% and a specificity of 62.2%. Limitations of this study include the lack of identification of optimal risk thresholds, as this requires additional information on the long-term benefits (e.g., life-years gained and mortality reduction) and harms (e.g., overdiagnosis) of risk-based screening strategies using these models. In addition, information on some predictor variables included in the risk prediction models was not available. Selection of individuals for lung cancer screening using individual risk is superior to selection criteria based on age and pack-years alone. The benefits, harms, and feasibility of implementing lung cancer screening policies based on risk prediction models should be assessed and compared with those of current recommendations.

  3. Data driven mathematical models for policy making

    OpenAIRE

    Nannyonga, Betty

    2011-01-01

    This thesis consists of two papers. 1. Betty Nannyonga, D.J.T. Sumpter, J.Y.T. Mugisha and L.S. Luboobi: The Dynamics,causes and possible prevention of Hepaititis E outbreaks. 2. Betty Nannyonga, D.J.T. Sumpter, andStam Nicolis: A dynamical systems approach tosocial and economic development. The first paper deals with a deterministic approach of modelling a Hepatitis E outbreak whenmalaria is endemic in a population. We design three models based on the epidemiology ofHepatitis E, malaria, and...

  4. Considering Planetary Constraints and Dynamic Screening in Solar Evolution Modeling

    Science.gov (United States)

    Wood, Suzannah R.; Mussack, Katie; Guzik, Joyce A.

    2018-01-01

    The ‘faint early sun problem’ remains unsolved. This problem consists of the apparent contradiction between the standard solar model prediction of lower luminosity (70% of current luminosity) and the observations of liquid water on early Earth and Mars. The presence of liquid water on early Earth and Mars should not be neglected and should be used as a constraint for solar evolution modeling. In addition, modifications to standard solar models are needed to address the discrepancy with solar structure inferred from helioseismology given the latest solar abundance determinations. Here, we will utilize the three different solar abundances: GN93 (Grevesse & Noels, 1993), AGS05 (Asplund et al., 2005), AGSS09 (Asplund et al., 2009). Here, we propose an early mass loss model with an initial solar mass between 1.07 and 1.15 solar masses and an exponentially decreasing mass-loss rate to meet conditions in the early solar system (Wood et al, submitted). Additionally, we investigate the effects of dynamic screening and the new OPLIB opacities from Los Alamos (Colgan et al., 2016). We show the effects of these modifications to the standard solar evolution models on the interior structure, neutrino fluxes, sound speed, p-mode frequencies, convection zone depth, and envelope helium and element abundance of the model sun at the present day.

  5. The role of public policies in reducing smoking prevalence: results from the Michigan SimSmoke tobacco policy simulation model.

    Science.gov (United States)

    Levy, David T; Huang, An-Tsun; Havumaki, Joshua S; Meza, Rafael

    2016-05-01

    Michigan has implemented several of the tobacco control policies recommended by the World Health Organization MPOWER goals. We consider the effect of those policies and additional policies consistent with MPOWER goals on smoking prevalence and smoking-attributable deaths (SADs). The SimSmoke tobacco control policy simulation model is used to examine the effect of past policies and a set of additional policies to meet the MPOWER goals. The model is adapted to Michigan using state population, smoking, and policy data starting in 1993. SADs are estimated using standard attribution methods. Upon validating the model, SimSmoke is used to distinguish the effect of policies implemented since 1993 against a counterfactual with policies kept at their 1993 levels. The model is then used to project the effect of implementing stronger policies beginning in 2014. SimSmoke predicts smoking prevalence accurately between 1993 and 2010. Since 1993, a relative reduction in smoking rates of 22 % by 2013 and of 30 % by 2054 can be attributed to tobacco control policies. Of the 22 % reduction, 44 % is due to taxes, 28 % to smoke-free air laws, 26 % to cessation treatment policies, and 2 % to youth access. Moreover, 234,000 SADs are projected to be averted by 2054. With additional policies consistent with MPOWER goals, the model projects that, by 2054, smoking prevalence can be further reduced by 17 % with 80,000 deaths averted relative to the absence of those policies. Michigan SimSmoke shows that tobacco control policies, including cigarette taxes, smoke-free air laws, and cessation treatment policies, have substantially reduced smoking and SADs. Higher taxes, strong mass media campaigns, and cessation treatment policies would further reduce smoking prevalence and SADs.

  6. Stochastic modelling for financial bubbles and policy

    OpenAIRE

    Fry, John

    2015-01-01

    In this paper, we draw upon the close relationship between statistical physics and mathematical finance to develop a suite of models for financial bubbles and crashes. By modifying previous approaches, we are able to derive novel analytical formulae for evaluation problems and for the expected timing of future change points. In particular, we help to explain why previous approaches have systematically overstated the timing of changes in market regime. The list of potential empirical applicati...

  7. Survey of prenatal screening policies in Europe for structural malformations and chromosome anomalies, and their impact on detection and termination rates for neural tube defects and Down's syndrome

    DEFF Research Database (Denmark)

    Boyd, P A; Devigan, C; Khoshnood, B

    2008-01-01

    tube defects (NTDs) using the EUROCAT database. MAIN OUTCOME MEASURES: Existence of national prenatal screening policies, legal gestation limit for TOPFA, prenatal detection and termination rates for Down's syndrome and NTD. RESULTS: Ten of the 18 countries had a national country-wide policy for Down...... cases. Six of the 18 countries had a legal gestational age limit for TOPFA, and in two countries, termination of pregnancy was illegal at any gestation. CONCLUSIONS: There are large differences in screening policies between countries in Europe. These, as well as organisational and cultural factors...

  8. Modeling policy issues in a world of imperfect competition

    DEFF Research Database (Denmark)

    Dierker, Egbert; Grodal, Birgit

    1998-01-01

    General equilibrium theory constitutes a sound basis for the discussion of policy issues if firms do not have market power. However, if firms influence prices strategically, the concept of profits loses its meaning due to the price normalization problem. Hence, it is unclear how to model the beha......General equilibrium theory constitutes a sound basis for the discussion of policy issues if firms do not have market power. However, if firms influence prices strategically, the concept of profits loses its meaning due to the price normalization problem. Hence, it is unclear how to model...... as well as on shareholders' aggregate demand...

  9. Stochastic modelling for financial bubbles and policy

    Directory of Open Access Journals (Sweden)

    John Fry

    2015-12-01

    Full Text Available In this paper, we draw upon the close relationship between statistical physics and mathematical finance to develop a suite of models for financial bubbles and crashes. By modifying previous approaches, we are able to derive novel analytical formulae for evaluation problems and for the expected timing of future change points. In particular, we help to explain why previous approaches have systematically overstated the timing of changes in market regime. The list of potential empirical applications is deep and wide ranging, and includes contemporary housing bubbles, the Eurozone crisis and the Crash of 2008.

  10. Awareness of cervical cancer and willingness to participate in screening program: Public health policy implications.

    Science.gov (United States)

    Patra, Somdatta; Upadhyay, Madhu; Chhabra, Pragti

    2017-01-01

    Cervical cancer is one of the most common malignancies among women in India. There is a high mortality as patients usually present at an advanced stage because of lack of awareness and nonexistent screening programs. This study was planned to find out awareness about cervical cancer among women and their willingness to utilize screening services in an urban resettlement colony of Delhi, India. A community-based, cross-sectional study was carried out in a resettlement colony of North-West Delhi. Semi-structured interview schedule was used to collect information regarding different aspects of cervical cancer. Analysis was done using SPSS package (SPSS version 16 (UCMS and GTBH, Delhi, India)). A total of 373 women were included in the study. Mean age of study participants was 39.14 years. Two-third of the study population were illiterate. Half of the study population was aware of cervical cancer, and only one-fourth of population were willing to participate in a screening test. Willingness was higher among educated, ever user of family planning method and having knowledge about at least one risk factor, signs or symptoms, or possibility of early diagnosis of cancer cervix. The country's national program advocates for opportunistic and targeted screening of women. An understanding of the factors that influences womens' willingness to participate in screening program is essential for the success of such programs. Hence, this study emphasizes the need for dissemination of knowledge about various aspects of cancer cervix which is critical for uptake of any screening program in a developing country.

  11. Modeling sequential context effects in diagnostic interpretation of screening mammograms.

    Science.gov (United States)

    Alamudun, Folami; Paulus, Paige; Yoon, Hong-Jun; Tourassi, Georgia

    2018-07-01

    Prior research has shown that physicians' medical decisions can be influenced by sequential context, particularly in cases where successive stimuli exhibit similar characteristics when analyzing medical images. This type of systematic error is known to psychophysicists as sequential context effect as it indicates that judgments are influenced by features of and decisions about the preceding case in the sequence of examined cases, rather than being based solely on the peculiarities unique to the present case. We determine if radiologists experience some form of context bias, using screening mammography as the use case. To this end, we explore correlations between previous perceptual behavior and diagnostic decisions and current decisions. We hypothesize that a radiologist's visual search pattern and diagnostic decisions in previous cases are predictive of the radiologist's current diagnostic decisions. To test our hypothesis, we tasked 10 radiologists of varied experience to conduct blind reviews of 100 four-view screening mammograms. Eye-tracking data and diagnostic decisions were collected from each radiologist under conditions mimicking clinical practice. Perceptual behavior was quantified using the fractal dimension of gaze scanpath, which was computed using the Minkowski-Bouligand box-counting method. To test the effect of previous behavior and decisions, we conducted a multifactor fixed-effects ANOVA. Further, to examine the predictive value of previous perceptual behavior and decisions, we trained and evaluated a predictive model for radiologists' current diagnostic decisions. ANOVA tests showed that previous visual behavior, characterized by fractal analysis, previous diagnostic decisions, and image characteristics of previous cases are significant predictors of current diagnostic decisions. Additionally, predictive modeling of diagnostic decisions showed an overall improvement in prediction error when the model is trained on additional information about

  12. An Integrative Behavioral Model of Information Security Policy Compliance

    Directory of Open Access Journals (Sweden)

    Sang Hoon Kim

    2014-01-01

    Full Text Available The authors found the behavioral factors that influence the organization members’ compliance with the information security policy in organizations on the basis of neutralization theory, Theory of planned behavior, and protection motivation theory. Depending on the theory of planned behavior, members’ attitudes towards compliance, as well as normative belief and self-efficacy, were believed to determine the intention to comply with the information security policy. Neutralization theory, a prominent theory in criminology, could be expected to provide the explanation for information system security policy violations. Based on the protection motivation theory, it was inferred that the expected efficacy could have an impact on intentions of compliance. By the above logical reasoning, the integrative behavioral model and eight hypotheses could be derived. Data were collected by conducting a survey; 194 out of 207 questionnaires were available. The test of the causal model was conducted by PLS. The reliability, validity, and model fit were found to be statistically significant. The results of the hypotheses tests showed that seven of the eight hypotheses were acceptable. The theoretical implications of this study are as follows: (1 the study is expected to play a role of the baseline for future research about organization members’ compliance with the information security policy, (2 the study attempted an interdisciplinary approach by combining psychology and information system security research, and (3 the study suggested concrete operational definitions of influencing factors for information security policy compliance through a comprehensive theoretical review. Also, the study has some practical implications. First, it can provide the guideline to support the successful execution of the strategic establishment for the implement of information system security policies in organizations. Second, it proves that the need of education and training

  13. An integrative behavioral model of information security policy compliance.

    Science.gov (United States)

    Kim, Sang Hoon; Yang, Kyung Hoon; Park, Sunyoung

    2014-01-01

    The authors found the behavioral factors that influence the organization members' compliance with the information security policy in organizations on the basis of neutralization theory, Theory of planned behavior, and protection motivation theory. Depending on the theory of planned behavior, members' attitudes towards compliance, as well as normative belief and self-efficacy, were believed to determine the intention to comply with the information security policy. Neutralization theory, a prominent theory in criminology, could be expected to provide the explanation for information system security policy violations. Based on the protection motivation theory, it was inferred that the expected efficacy could have an impact on intentions of compliance. By the above logical reasoning, the integrative behavioral model and eight hypotheses could be derived. Data were collected by conducting a survey; 194 out of 207 questionnaires were available. The test of the causal model was conducted by PLS. The reliability, validity, and model fit were found to be statistically significant. The results of the hypotheses tests showed that seven of the eight hypotheses were acceptable. The theoretical implications of this study are as follows: (1) the study is expected to play a role of the baseline for future research about organization members' compliance with the information security policy, (2) the study attempted an interdisciplinary approach by combining psychology and information system security research, and (3) the study suggested concrete operational definitions of influencing factors for information security policy compliance through a comprehensive theoretical review. Also, the study has some practical implications. First, it can provide the guideline to support the successful execution of the strategic establishment for the implement of information system security policies in organizations. Second, it proves that the need of education and training programs suppressing

  14. Production functions for climate policy modeling. An empirical analysis

    International Nuclear Information System (INIS)

    Van der Werf, Edwin

    2008-01-01

    Quantitative models for climate policy modeling differ in the production structure used and in the sizes of the elasticities of substitution. The empirical foundation for both is generally lacking. This paper estimates the parameters of 2-level CES production functions with capital, labour and energy as inputs, and is the first to systematically compare all nesting structures. Using industry-level data from 12 OECD countries, we find that the nesting structure where capital and labour are combined first, fits the data best, but for most countries and industries we cannot reject that all three inputs can be put into one single nest. These two nesting structures are used by most climate models. However, while several climate policy models use a Cobb-Douglas function for (part of the) production function, we reject elasticities equal to one, in favour of considerably smaller values. Finally we find evidence for factor-specific technological change. With lower elasticities and with factor-specific technological change, some climate policy models may find a bigger effect of endogenous technological change on mitigating the costs of climate policy. (author)

  15. A screening-level modeling approach to estimate nitrogen ...

    Science.gov (United States)

    This paper presents a screening-level modeling approach that can be used to rapidly estimate nutrient loading and assess numerical nutrient standard exceedance risk of surface waters leading to potential classification as impaired for designated use. It can also be used to explore best management practice (BMP) implementation to reduce loading. The modeling framework uses a hybrid statistical and process based approach to estimate source of pollutants, their transport and decay in the terrestrial and aquatic parts of watersheds. The framework is developed in the ArcGIS environment and is based on the total maximum daily load (TMDL) balance model. Nitrogen (N) is currently addressed in the framework, referred to as WQM-TMDL-N. Loading for each catchment includes non-point sources (NPS) and point sources (PS). NPS loading is estimated using export coefficient or event mean concentration methods depending on the temporal scales, i.e., annual or daily. Loading from atmospheric deposition is also included. The probability of a nutrient load to exceed a target load is evaluated using probabilistic risk assessment, by including the uncertainty associated with export coefficients of various land uses. The computed risk data can be visualized as spatial maps which show the load exceedance probability for all stream segments. In an application of this modeling approach to the Tippecanoe River watershed in Indiana, USA, total nitrogen (TN) loading and risk of standard exce

  16. Mapping and modelling ecosystem services for science, policy and practice

    NARCIS (Netherlands)

    Burkhard, B.; Crossman, N.; Nedkov, S.; Petz, K.; Alkemade, R.

    2013-01-01

    Ecosystem services are a significant research and policy topic and there are many modelling and mapping approaches aimed at understanding the stocks, demands and flows of ecosystem services on different spatial and temporal scales. The integration of geo-biophysical processes and structure

  17. An applied general equilibrium model for Dutch agribusiness policy analysis

    NARCIS (Netherlands)

    Peerlings, J.

    1993-01-01

    The purpose of this thesis was to develop a basic static applied general equilibrium (AGE) model to analyse the effects of agricultural policy changes on Dutch agribusiness. In particular the effects on inter-industry transactions, factor demand, income, and trade are of

  18. Using an Ocean of Data, Researchers Model Real-Life Benefits of Cancer Screening

    Science.gov (United States)

    Using the results of screening trials, the NCI Cancer Intervention and Surveillance Modeling Network is trying to estimate the true benefit of cancer screening in the general population and identify the optimal way to implement screening within the health care system.

  19. Breast cancer risk prediction model: a nomogram based on common mammographic screening findings

    NARCIS (Netherlands)

    Timmers, J.M.H.; Verbeek, A.L.M.; Hout, J. in't; Pijnappel, R.M.; Broeders, M.J.M.; Heeten, G.J. den

    2013-01-01

    OBJECTIVES: To develop a prediction model for breast cancer based on common mammographic findings on screening mammograms aiming to reduce reader variability in assigning BI-RADS. METHODS: We retrospectively reviewed 352 positive screening mammograms of women participating in the Dutch screening

  20. Breast cancer risk prediction model: a nomogram based on common mammographic screening findings

    NARCIS (Netherlands)

    Timmers, J. M. H.; Verbeek, A. L. M.; Inthout, J.; Pijnappel, R. M.; Broeders, M. J. M.; den Heeten, G. J.

    2013-01-01

    To develop a prediction model for breast cancer based on common mammographic findings on screening mammograms aiming to reduce reader variability in assigning BI-RADS. We retrospectively reviewed 352 positive screening mammograms of women participating in the Dutch screening programme (Nijmegen

  1. Quantification model of the consequences of monetary policy shocks

    Directory of Open Access Journals (Sweden)

    Coralia Emilia POPA

    2017-11-01

    Full Text Available The monetary analysis based on the BVAR (Bayesian Vector Autoregression model is extremely important in the monetary policy implementation strategy, the information provided is important not only for the Central Bank, but also for the economic agents and the population. Therefore, conducting this analysis at the level of Romania helps to understand better the mechanism by which monetary policy is transmitted in order to achieve the set target, namely inflation targeting, but it also provides us with important information regarding the accession to the euro area. The model we are trying to test helps us understand through the correlations between the interest rate, GDP and the inflation rate how monetary policy responds to shocks. The model follows the methodology presented by Sims and Zha (1998 in the paper "Bayesian Methods for Dynamic Multivariate Models and Using the Bayesian Autoregressive Vector". In the analysis of this model, quarterly data for a minimum of three years, three variables are used to make the results relevant. The data needed to model the model are used in logarithmic form, except for the interest rate, and the outcome is applied to a differentiated premium operator. Of the variables used, the interest rate is the only one that does not allow seasonal adjustment.

  2. What Can Policy Analysis Add to Evaluation Research?: Predictive Modeling and Policy Optimization.

    Science.gov (United States)

    Nagel, Stuart S.

    Policy analysis, or policy study, is defined as the study of the nature, causes, and effects of alternative public policies; sometimes policy analysis refers to specific methods used. Two new developments associated with policy analysis are discussed. One is the concern for deducing the effects of alternative policies before they are adopted, as…

  3. Validation of a model to estimate personalised screening frequency to monitor diabetic retinopathy.

    Science.gov (United States)

    van der Heijden, Amber A W A; Walraven, Iris; van 't Riet, Esther; Aspelund, Thor; Lund, Sigrún H; Elders, Petra; Polak, Bettine C P; Moll, Annette C; Keunen, Jan E E; Dekker, Jacqueline M; Nijpels, Giel

    2014-07-01

    Our study aimed to validate a model to determine a personalised screening frequency for diabetic retinopathy. A model calculating a personalised screening interval for monitoring retinopathy based on patients' risk profile was validated using the data of 3,319 type 2 diabetic patients in the Diabetes Care System West-Friesland, the Netherlands. Two-field fundus photographs were graded according to the EURODIAB coding system. Sight-threatening retinopathy (STR) was considered to be grades 3-5. Validity of the model was assessed using calibration and discrimination measures. We compared model-based time of screening with time of STR diagnosis and calculated the differences in the number of fundus photographs using the model compared with those in annual or biennial screening. During a mean of 53 months of follow-up, 76 patients (2.3%) developed STR. Using the model, the mean screening interval was 31 months, leading to a reduced screening frequency of 61% compared with annual screening and 23% compared with biennial screening. STR incidence occurred after a mean of 26 months after the model-based time of screening in 67 patients (88.2%). In nine patients (11.8%), STR had developed before the model-based time of screening. The discriminatory ability of the model was good (C-statistic 0.83; 95% CI 0.74, 0.92). Calibration showed that the model overestimated STR risk. A large reduction in retinopathy screening was achieved using the model in this population of patients with a very low incidence of retinopathy. Considering the number of potentially missed cases of STR, there is room for improvement in the model. Use of the model for personalised screening may eventually help to reduce healthcare use and costs of diabetes care.

  4. A Computational model for compressed sensing RNAi cellular screening

    Directory of Open Access Journals (Sweden)

    Tan Hua

    2012-12-01

    Full Text Available Abstract Background RNA interference (RNAi becomes an increasingly important and effective genetic tool to study the function of target genes by suppressing specific genes of interest. This system approach helps identify signaling pathways and cellular phase types by tracking intensity and/or morphological changes of cells. The traditional RNAi screening scheme, in which one siRNA is designed to knockdown one specific mRNA target, needs a large library of siRNAs and turns out to be time-consuming and expensive. Results In this paper, we propose a conceptual model, called compressed sensing RNAi (csRNAi, which employs a unique combination of group of small interfering RNAs (siRNAs to knockdown a much larger size of genes. This strategy is based on the fact that one gene can be partially bound with several small interfering RNAs (siRNAs and conversely, one siRNA can bind to a few genes with distinct binding affinity. This model constructs a multi-to-multi correspondence between siRNAs and their targets, with siRNAs much fewer than mRNA targets, compared with the conventional scheme. Mathematically this problem involves an underdetermined system of equations (linear or nonlinear, which is ill-posed in general. However, the recently developed compressed sensing (CS theory can solve this problem. We present a mathematical model to describe the csRNAi system based on both CS theory and biological concerns. To build this model, we first search nucleotide motifs in a target gene set. Then we propose a machine learning based method to find the effective siRNAs with novel features, such as image features and speech features to describe an siRNA sequence. Numerical simulations show that we can reduce the siRNA library to one third of that in the conventional scheme. In addition, the features to describe siRNAs outperform the existing ones substantially. Conclusions This csRNAi system is very promising in saving both time and cost for large-scale RNAi

  5. A Computable OLG Model for Gender and Growth Policy Analysis

    OpenAIRE

    Pierre-Richard Agénor

    2012-01-01

    This paper develops a computable Overlapping Generations (OLG) model for gender and growth policy analysis. The model accounts for human and physical capital accumulation (both public and private), intra- and inter-generational health persistence, fertility choices, and women's time allocation between market work, child rearing, and home production. Bargaining between spouses and gender bias, in the form of discrimination in the work place and mothers' time allocation between daughters and so...

  6. Generating WS-SecurityPolicy documents via security model transformation

    DEFF Research Database (Denmark)

    Jensen, Meiko

    2009-01-01

    When SOA-based business processes are to be enhanced with security properties, the model-driven business process development approach enables an easier and more reliable security definition compared to manually crafting the security realizations afterwards. In this paper, we outline an appropriate...... security model definition and transformation approach, targeting the WS-SecurityPolicy and WS-BPEL specifications, in order to enable a Web-Service-based secure business process development....

  7. Japan Turns Pro-Life: Recent Change in Reproductive Health Policy and Controversies over Prenatal Screening

    Directory of Open Access Journals (Sweden)

    Etsuji Okamoto

    2014-02-01

    Full Text Available Japan, known as a pro-choice country in terms of abortion, is currently facing the increase of “selective abortions” thanks to new prenatal screening. Efforts to restrict proliferation of new technology has not been successful and it is likely that Japan will turn pro-life by strictly enforcing the Maternity Protection Act (MPA, which prohibits abortions due to “fetal cause”.

  8. Replenishment policy for an inventory model under inflation

    Science.gov (United States)

    Singh, Vikramjeet; Saxena, Seema; Singh, Pushpinder; Mishra, Nitin Kumar

    2017-07-01

    The purpose of replenishment is to keep the flow of inventory in the system. To determine an optimal replenishment policy is a great challenge in developing an inventory model. Inflation is defined as the rate at which the prices of goods and services are rising over a time period. The cost parameters are affected by the rate of inflation. High rate of inflation affects the organizations financial conditions. Based on the above backdrop the present paper proposes the retailers replenishment policy for deteriorating items with different cycle lengths under inflation. The shortages are partially backlogged. At last numerical examples validate the results.

  9. Advancing LGBT Elder Policy and Support Services: The Massachusetts Model.

    Science.gov (United States)

    Krinsky, Lisa; Cahill, Sean R

    2017-12-01

    The Massachusetts-based LGBT Aging Project has trained elder service providers in affirming and culturally competent care for LGBT older adults, supported development of LGBT-friendly meal programs, and advanced LGBT equality under aging policy. Working across sectors, this innovative model launched the country's first statewide Legislative Commission on Lesbian, Gay, Bisexual, and Transgender Aging. Advocates are working with policymakers to implement key recommendations, including cultural competency training and data collection in statewide networks of elder services. The LGBT Aging Project's success provides a template for improving services and policy for LGBT older adults throughout the country.

  10. Sources of change in foreign policy. A review of foreign policy models for developing countries

    Directory of Open Access Journals (Sweden)

    Alba E. Gámez

    2005-05-01

    Full Text Available The study of what could be called the reorientation of State foreign policy is not a new phenomenon. Changes in alliances, economic partners and attitudes in the face of international issues have been reflected in myriad texts. Nevertheless, few theoretical frameworksdeal with this issue as an area of study in and of itself. Overcoming this situation would contribute to identifying and comparing the changes in attitude and discourse in the relations between countries, especially in the case of developing countries, and, by extension, thesources of these changes. This article reviews the different models for the analysis of foreign policy, using the conceptual framework of Hermann (1990 as its starting point. This framework suggests the existence of four graded levels of change which allow for studying forms of change which are subtle but important in foreign policy; it also offers a reasoned analysis for testing the relative importance of their sources. This conceptual framework can be situated in the traditional division of levels of analysis: the characteristics of the leader, bureaucratic proposer, internal adjustment, and external impact; and, while it does not provide a conclusive answer, it may be a useful tool in clarifying the ways of using empirical evidence and establishing the relative importance of the sources of change in foreign policy orientation.

  11. What model of science? Towards a sociologically oriented science policy

    Directory of Open Access Journals (Sweden)

    Dorota Jedlikowska

    2015-09-01

    Full Text Available In the contemporary global world the various models of making and distributing science are cultivated. The particular model of institutionalized science can significantly determine the quality of working both as a scientist and as a student. Research upon science environment in the meaning of investigation the framework of science influences for example the system of communication between different actors engaged in science, good practices, possibilities offered by particular context of science and facilities of acquiring the scientific knowledge etc. It this view the presented paper finds its justification directing analysis towards the quality of making science. Hence the paradigm of sociological science policy is strongly needed. The paper is going to reconstruct the key models which recognize contexts of making science and its numerous dimensions. The research is based on the set of literature founded through the digital key words searching process. The chosen literature recalls the most significant research based on science policy. Consequently the described models tend towards the most globalized and open models of making science to show the path of required changes into still founded coercive science structures mostly institutionalized by long-lasting tradition. The final conclusion states that more concrete steps in reformulating the science policy are required to obtain the desirable model of open science and at the same time to develop the high standing scientific priorities.

  12. Dynamic and adaptive policy models for coalition operations

    Science.gov (United States)

    Verma, Dinesh; Calo, Seraphin; Chakraborty, Supriyo; Bertino, Elisa; Williams, Chris; Tucker, Jeremy; Rivera, Brian; de Mel, Geeth R.

    2017-05-01

    It is envisioned that the success of future military operations depends on the better integration, organizationally and operationally, among allies, coalition members, inter-agency partners, and so forth. However, this leads to a challenging and complex environment where the heterogeneity and dynamism in the operating environment intertwines with the evolving situational factors that affect the decision-making life cycle of the war fighter. Therefore, the users in such environments need secure, accessible, and resilient information infrastructures where policy-based mechanisms adopt the behaviours of the systems to meet end user goals. By specifying and enforcing a policy based model and framework for operations and security which accommodates heterogeneous coalitions, high levels of agility can be enabled to allow rapid assembly and restructuring of system and information resources. However, current prevalent policy models (e.g., rule based event-condition-action model and its variants) are not sufficient to deal with the highly dynamic and plausibly non-deterministic nature of these environments. Therefore, to address the above challenges, in this paper, we present a new approach for policies which enables managed systems to take more autonomic decisions regarding their operations.

  13. Coronary heart disease policy models: a systematic review

    Directory of Open Access Journals (Sweden)

    Capewell Simon

    2006-08-01

    Full Text Available Abstract Background The prevention and treatment of coronary heart disease (CHD is complex. A variety of models have therefore been developed to try and explain past trends and predict future possibilities. The aim of this systematic review was to evaluate the strengths and limitations of existing CHD policy models. Methods A search strategy was developed, piloted and run in MEDLINE and EMBASE electronic databases, supplemented by manually searching reference lists of relevant articles and reviews. Two reviewers independently checked the papers for inclusion and appraisal. All CHD modelling studies were included which addressed a defined population and reported on one or more key outcomes (deaths prevented, life years gained, mortality, incidence, prevalence, disability or cost of treatment. Results In total, 75 articles describing 42 models were included; 12 (29% of the 42 models were micro-simulation, 8 (19% cell-based, and 8 (19% life table analyses, while 14 (33% used other modelling methods. Outcomes most commonly reported were cost-effectiveness (36%, numbers of deaths prevented (33%, life-years gained (23% or CHD incidence (23%. Among the 42 models, 29 (69% included one or more risk factors for primary prevention, while 8 (19% just considered CHD treatments. Only 5 (12% were comprehensive, considering both risk factors and treatments. The six best-developed models are summarised in this paper, all are considered in detail in the appendices. Conclusion Existing CHD policy models vary widely in their depth, breadth, quality, utility and versatility. Few models have been calibrated against observed data, replicated in different settings or adequately validated. Before being accepted as a policy aid, any CHD model should provide an explicit statement of its aims, assumptions, outputs, strengths and limitations.

  14. A Model of Climate Policy Using Board Game Mechanics

    Directory of Open Access Journals (Sweden)

    Edward Castronova

    2015-09-01

    Full Text Available This paper provides a case study of how a board game can be modified to generate a serious game. We argue that board games are an interesting medium for serious games, especially when the goal is to teach players about particularly complex systems. In that case, the transparency of a board game makes it possible for players to “see the whole boards” – to see all of the various moving parts at work. That transparency also makes it very easy to modify board games. To demonstrate these claims, we present a modification to the board game CO2 that accurately models different policy options with regard to global warming. We show how a few major changes to the original game’s point systems, as well as removal of certain extraneous features, can significantly improve the game, adding an instructional value. The game allows players to experiment with several policy options, including carbon taxes, carbon emissions permit sales, and clean energy research support, and lets players see how these policies interact. We discuss ways that teachers, advocates, journalists, and others can the Climate Policy mod to more easily explain the incredibly complex interactions of power markets, carbon dioxide emissions, and public policy.

  15. Energy modelling platforms for policy and strategy support

    International Nuclear Information System (INIS)

    Dyner, I.

    2000-01-01

    The energy field has been dominated by 'hard' modelling approaches by researchers from engineering and economics discipline. The recent trend towards a more liberalised environment moves away from central planning to market-based resource allocation, leading to the creation and use of strategic tools, with much 'softer' specifications, in the 'system-thinking' tradition. This paper presents the use of system dynamics in a generalised way, to provide a platform for integrated energy analysis. Issues of modularity and policy evolution are important in the design of the modelling platform to facilitate its use, and reuse. Hence the concepts of a platform, rather than a model, has to be implemented in a coherent way if it is to provide sustained value for ongoing support to both government policy and corporate strategy. (author)

  16. Bridging Research, Practice, and Policy: The "Evidence Academy" Conference Model.

    Science.gov (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

    2016-01-01

    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.

  17. Health behavior change models and their socio-cultural relevance for breast cancer screening in African American women.

    Science.gov (United States)

    Ashing-Giwa, K

    1999-01-01

    Models of health behavior provide the conceptual bases for most of the breast cancer screening intervention studies. These models were not designed for and have not been adequately tested with African American women. The models discussed in this paper are: The Health Belief Model, the Theory of Reasoned Action/Theory of Planned Behavior, and the Transtheoretical Model. This paper will examine the socio-cultural relevance of these health behavior models, and discuss specific socio-cultural dimensions that are not accounted for by these paradigms. It is critical that researchers include socio-cultural dimensions, such as interconnectedness, health socialization, ecological factors and health care system factors into their intervention models with African American women. Comprehensive and socio-culturally based investigations are necessary to guide the scientific and policy challenge for reducing breast cancer mortality in African American women.

  18. Seeing through the public health smoke-screen in drug policy.

    Science.gov (United States)

    Csete, Joanne; Wolfe, Daniel

    2017-05-01

    In deliberations on drug policy in United Nations fora, a consensus has emerged that drug use and drug dependence should be treated primarily as public health concerns rather than as crimes. But what some member states mean by "public health approach" merits scrutiny. Some governments that espouse treating people who use drugs as "patients, not criminals" still subject them to prison-like detention in the name of drug-dependence treatment or otherwise do not take measures to provide scientifically sound treatment and humane social support to those who need them. Even drug treatment courts, which the U.S. and other countries hold up as examples of a public health approach to drug dependence, can serve rather to tighten the hold of the criminal justice sector on concerns that should be addressed in the health sector. The political popularity of demonisation of drugs and visibly repressive approaches is an obvious challenge to leadership for truly health-oriented drug control. This commentary offers some thoughts for judging whether a public health approach is worthy of the name and cautions drug policy reformers not to rely on facile commitments to health approaches that are largely rhetorical or that mask policies and activities not in keeping with good public health practise. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Screening model for nanowire surface-charge sensors in liquid

    DEFF Research Database (Denmark)

    Sørensen, Martin Hedegård; Mortensen, Asger; Brandbyge, Mads

    2007-01-01

    The conductance change of nanowire field-effect transistors is considered a highly sensitive probe for surface charge. However, Debye screening of relevant physiological liquid environments challenge device performance due to competing screening from the ionic liquid and nanowire charge carriers....

  20. Pharmaceutical expenditure forecast model to support health policy decision making

    Science.gov (United States)

    Rémuzat, Cécile; Urbinati, Duccio; Kornfeld, Åsa; Vataire, Anne-Lise; Cetinsoy, Laurent; Aballéa, Samuel; Mzoughi, Olfa; Toumi, Mondher

    2014-01-01

    Background and objective With constant incentives for healthcare payers to contain their pharmaceutical budgets, modelling policy decision impact became critical. The objective of this project was to test the impact of various policy decisions on pharmaceutical budget (developed for the European Commission for the project ‘European Union (EU) Pharmaceutical expenditure forecast’ – http://ec.europa.eu/health/healthcare/key_documents/index_en.htm). Methods A model was built to assess policy scenarios’ impact on the pharmaceutical budgets of seven member states of the EU, namely France, Germany, Greece, Hungary, Poland, Portugal, and the United Kingdom. The following scenarios were tested: expanding the UK policies to EU, changing time to market access, modifying generic price and penetration, shifting the distribution chain of biosimilars (retail/hospital). Results Applying the UK policy resulted in dramatic savings for Germany (10 times the base case forecast) and substantial additional savings for France and Portugal (2 and 4 times the base case forecast, respectively). Delaying time to market was found be to a very powerful tool to reduce pharmaceutical expenditure. Applying the EU transparency directive (6-month process for pricing and reimbursement) increased pharmaceutical expenditure for all countries (from 1.1 to 4 times the base case forecast), except in Germany (additional savings). Decreasing the price of generics and boosting the penetration rate, as well as shifting distribution of biosimilars through hospital chain were also key methods to reduce pharmaceutical expenditure. Change in the level of reimbursement rate to 100% in all countries led to an important increase in the pharmaceutical budget. Conclusions Forecasting pharmaceutical expenditure is a critical exercise to inform policy decision makers. The most important leverages identified by the model on pharmaceutical budget were driven by generic and biosimilar prices, penetration rate

  1. Useful models for simulating policies to induce technological change

    International Nuclear Information System (INIS)

    Rivers, Nic; Jaccard, Mark

    2006-01-01

    Conventional top-down and bottom-up energy-economy models have limitations that affect their usefulness to policy-makers. Efforts to develop hybrid models, that incorporate valuable aspects of these two frameworks, may be more useful by representing technologies in the energy-economy explicitly while also representing more realistically the way in which businesses and consumers choose between those technologies. This representation allows for the realistic simulation of a wide range of technology-specific regulations and fiscal incentives alongside economy-wide fiscal incentives and disincentives. These policies can be assessed based on the costs required to reach a goal in the medium term, as well as on the degree to which they induce technological change that affects costs over long time periods

  2. ND and NB systems in quark delocalization color screening model

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Lifang [Nanjing College of Information Technology, Department of Quality-Oriented Education, Nanjing (China); Huang, Hongxia; Ping, Jialun [Nanjing Normal University, Department of Physics, Nanjing (China)

    2017-02-15

    The ND and NB systems with I = 0 and 1, J{sup P} = (1)/(2){sup ±}, (3)/(2){sup ±}, and (5)/(2){sup ±} are investigated within the framework of the quark delocalization color screening model. The results show that all the positive-parity states are unbound. By coupling to the ND* channel, the state ND with I = 0, J{sup P} = (1)/(2){sup -} can form a bound state, which can be invoked to explain the observed Σ(2800) state. The mass of the ND* with I = 0, J{sup P} = (3)/(2){sup -} is close to that of the reported Λ{sub c}(2940){sup +}, which indicates that Λ{sub c}(2940){sup +} can be explained as a ND* molecular state in QDCSM. Besides, the ΔD* with I = 1, J{sup P} = (5)/(2){sup -} is also a possible resonance state. The results of the bottom case of the NB system are similar to those of the ND system. Searching for these states will be a challenging subject of experiments. (orig.)

  3. Modelling climate change policies : an application of ENERGY2020

    International Nuclear Information System (INIS)

    Timilsina, G.; Bhargava, A.; Backus, G.

    2005-01-01

    Researches and policy-makers are increasingly analyzing the economic impacts of the Kyoto Protocol at national, regional and global levels. The analyses are generally based on numerical models integrating energy, environment and the economy. Most models range from partial equilibrium types to complex multi-sector general equilibrium models, and typically represent the energy sector at an aggregate level, which limits their ability to reflect details of different sectors. In Canada, a model called ENERGY2020 has been widely used by the federal and provincial governments to analyze the sectoral and provincial impacts of implementing the Kyoto Protocol. ENERGY2020 uses stocks and flows simulation that captures the physical aspects of the processes utilizing energy, as well as the qualitative choice theory which captures human behavioural aspects. The model also has a database containing 20 years of time-series on all economic, environmental and energy variables, enabling the model to derive most parameters endogenously through econometric estimations. It has the capacity to analyze consumer and business responses over a wide range of policy initiatives such as energy environment taxes, regulatory standards for buildings, equipment and motor vehicles, grants, rebates and subsidy initiatives, consumer awareness initiatives, technology improvements, moratoriums and mandated cut-backs. It is also capable of producing long-term energy market forecasts as well as analyzing the impacts of policies in the markets. It was concluded that the model's application will serve as a useful analytical tool for a range of issues, and may be useful to developing countries and economies in transition. 6 refs., 5 figs

  4. THE MODEL FOR DIEGETIC ANALYSIS OF SOUNDS IN SCREEN MEDIA

    Directory of Open Access Journals (Sweden)

    Denikin Anton A.

    2013-12-01

    Full Text Available This article includes the analysis of the relationship between representational visual spaces and sounds in screen media. The methodology presented in this paper can be used for the accurate classification and differentiation for screen sounds, as well as for the general analysis of the specific sound of screen media. For this, the concept of «diegesis» is used. It allows us to analyze the spatial specificity of audiovisual images in cinematographic works and the spatial-functional interactive action in video games and others multimedia.

  5. Customizing G Protein-coupled receptor models for structure-based virtual screening

    NARCIS (Netherlands)

    de Graaf, C.; Rognan, D.

    2009-01-01

    This review will focus on the construction, refinement, and validation of G Protein-coupled receptor models for the purpose of structure-based virtual screening. Practical tips and tricks derived from concrete modeling and virtual screening exercises to overcome the problems and pitfalls associated

  6. Cross-Cultural Validation of the Preventive Health Model for Colorectal Cancer Screening: An Australian Study

    Science.gov (United States)

    Flight, Ingrid H.; Wilson, Carlene J.; McGillivray, Jane; Myers, Ronald E.

    2010-01-01

    We investigated whether the five-factor structure of the Preventive Health Model for colorectal cancer screening, developed in the United States, has validity in Australia. We also tested extending the model with the addition of the factor Self-Efficacy to Screen using Fecal Occult Blood Test (SESFOBT). Randomly selected men and women aged between…

  7. Validation of a model to estimate personalised screening frequency to monitor diabetic retinopathy

    NARCIS (Netherlands)

    Heijden, A.A. van der; Walraven, I.; Riet, E. van 't; Aspelund, T.; Lund, S.H.; Elders, P.; Polak, B.C.P.; Moll, A.C.; Keunen, J.E.E.; Dekker, J.M.; Nijpels, G.

    2014-01-01

    AIMS/HYPOTHESIS: Our study aimed to validate a model to determine a personalised screening frequency for diabetic retinopathy. METHODS: A model calculating a personalised screening interval for monitoring retinopathy based on patients' risk profile was validated using the data of 3,319 type 2

  8. Validation of a model to estimate personalised screening frequency to monitor diabetic retinopathy

    NARCIS (Netherlands)

    van der Heijden, A.A.W.A.; Walraven, I.; van 't Riet, E.; Aspelund, T.; Lund, S.H.; Elders, P.J.M.; Polak, B.C.P.; Moll, A.C.; Keunen, J.E.E.; Dekker, J.M.; Nijpels, G.

    2014-01-01

    Aims/hypothesis: Our study aimed to validate a model to determine a personalised screening frequency for diabetic retinopathy. Methods: A model calculating a personalised screening interval for monitoring retinopathy based on patients' risk profile was validated using the data of 3,319 type 2

  9. Screening for gestational diabetes mellitus by a model based on risk indicators: a prospective study

    DEFF Research Database (Denmark)

    Jensen, Dorte; Mølsted-Pedersen, Lars; Beck-Nielsen, Henning

    2003-01-01

    This study was performed to prospectively evaluate a screening model for gestational diabetes mellitus on the basis of clinical risk indicators.......This study was performed to prospectively evaluate a screening model for gestational diabetes mellitus on the basis of clinical risk indicators....

  10. The Role of Decision Models in Health Care Policy: A Case Study.

    Science.gov (United States)

    John-Baptiste, Ava; Schapira, Marilyn M; Cravens, Catherine; Chambers, James D; Neumann, Peter J; Siegel, Joanna; Lawrence, William

    2016-07-01

    In 2009, the Centers for Medicare and Medicaid Services (CMS) underwent a National Coverage Determination on computed tomography colonography (CTC) to screen for colorectal cancer. The Cancer Intervention & Surveillance Network developed decision models to inform this decision. The purpose of our study was to investigate the role of models in this decision. We performed a descriptive case study. We conducted semistructured telephone interviews with members of the CMS coverage and analysis group (CAG) and Medicare Coverage and Analysis Advisory Committee (MEDCAC) panelists. Informed by previously published literature, we developed a coding scheme to analyze interview transcripts, MEDCAC meeting transcripts, and the final CMS decision memo. Four members of the CAG and 8 MEDCAC panelists were interviewed. The total number of codes across all study documents was 772. We found evidence that decision makers believed in the adequacy of models to inform decision making. In interview transcripts, the code Models Are Adequate to Inform was more frequent than the code Models Are Inadequate to Inform (47 times v. 5). Discussion of model conceptualization dominated the MEDCAC meeting (Model Conceptualization assigned 113 times) and was frequently discussed during interviews (Model Conceptualization assigned 84 times). We also found evidence that the models helped to focus the policy discussion. Across study documents, the codes Focus on Cost, Focus on Clinical-Health Impact, and Focus on Inadequacy of Evidence Base were assigned 99, 98, and 97 times, respectively. Decision makers involved in the CTC decision believed in the adequacy of models to inform coverage decisions. The model played a role in focusing the CTC coverage policy discussion. © The Authors 2016.

  11. Population health outcome models in suicide prevention policy.

    Science.gov (United States)

    Lynch, Frances L

    2014-09-01

    Suicide is a leading cause of death in the U.S. and results in immense suffering and significant cost. Effective suicide prevention interventions could reduce this burden, but policy makers need estimates of health outcomes achieved by alternative interventions to focus implementation efforts. To illustrate the utility of health outcome models to help in achieving goals defined by the National Action Alliance for Suicide Prevention's Research Prioritization Task Force. The approach is illustrated specifically with psychotherapeutic interventions to prevent suicide reattempt in emergency department settings. A health outcome model using decision analysis with secondary data was applied to estimate suicide attempts and deaths averted from evidence-based interventions. Under optimal conditions, the model estimated that over 1 year, implementing evidence-based psychotherapeutic interventions in emergency departments could decrease the number of suicide attempts by 18,737, and if offered over 5 years, it could avert 109,306 attempts. Over 1 year, the model estimated 2,498 fewer deaths from suicide, and over 5 years, about 13,928 fewer suicide deaths. Health outcome models could aid in suicide prevention policy by helping focus implementation efforts. Further research developing more sophisticated models of the impact of suicide prevention interventions that include a more complex understanding of suicidal behavior, longer time frames, and inclusion of additional outcomes that capture the full benefits and costs of interventions would be helpful next steps. Copyright © 2014 American Journal of Preventive Medicine. All rights reserved.

  12. Anticipating the uncertain: economic modeling and climate change policy

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Svenn

    2012-11-01

    With this thesis I wish to contribute to the understanding of how uncertainty and the anticipation of future events by economic actors affect climate policies. The thesis consists of four papers. Two papers are analytical models which explicitly consider that emissions are caused by extracting scarce fossil fuels which in the future must be replaced by clean technologies. The other two are so called numerical integrated assessment models. Such models represent the world economy, the climate system and the interactions between those two quantitatively, complementing more abstract theoretical work. Should policy makers discriminate between subsidizing renewable energy sources such as wind or solar power, and technologies such as carbon capture and storage (CCS)? Focusing only on the dynamic supply of fossil fuels and hence Co{sub 2}, we find here that cheaper future renewables cause extraction to speed up, lower costs of CCS may delay it. CCS hence may dampen the dynamic inefficiency caused by the absence of comprehensive climate policies today. Does it matter whether uncertainty about future damage assessment is due to scientific complexities or stems from the political process? In paper two, I find that political and scientific uncertainties have opposing effects on the incentives to investment in renewables and the extraction of fossil fuels: The prospect of scientific learning about the climate system increases investment incentives and, ceteris paribus, slows extraction down; uncertainty about future political constellations does the opposite. The optimal carbon tax under scientific uncertainty equals expected marginal damages, whereas political uncertainty demands a tax below marginal damages that decreases over time. Does uncertainty about economic growth impact optimal climate policy today? Here we are the first to consistently analyze how uncertainty about future economic growth affects optimal emission reductions and the optimal social cost of carbon. We

  13. Imparting carrier status results detected by universal newborn screening for sickle cell and cystic fibrosis in England: a qualitative study of current practice and policy challenges

    Directory of Open Access Journals (Sweden)

    Ulph Fiona

    2007-12-01

    Full Text Available Abstract Background Universal newborn screening for early detection of children affected by sickle cell disorders and cystic fibrosis is currently being implemented across England. Parents of infants identified as carriers of these disorders must also be informed of their baby's result. However there is a lack of evidence for most effective practice internationally when doing so. This study describes current or proposed models for imparting this information in practice and explores associated challenges for policy. Methods Thematic analysis of semi-structured interviews with Child Health Coordinators from all English Health Regions. Results Diverse methods for imparting carrier results, both within and between regions, and within and between conditions, were being implemented or planned. Models ranged from result by letter to in-person communication during a home visit. Non-specialists were considered the best placed professionals to give results and a similar approach for both conditions was emphasised. While national guidance has influenced choice of models, other factors contributed such as existing service structures and lack of funding. Challenges included uncertainty about guidance specifying face to face notification; how best to balance allaying parental anxiety by using familiar non-specialist health professionals with concerns about practitioner competence; and extent of information parents should be given. Inadequate consideration of resource and service workload was seen as the main policy obstacle. Clarification of existing guidance; more specific protocols to ensure consistent countrywide practice; integration of the two programmes; and 'normalising' carrier status were suggested as improvements. Conclusion Differing models for communicating carrier results raise concerns about equity and clinical governance. However, this variation provides opportunity for evaluation. Timely and more detailed guidance on protocols with

  14. A Nuclear Waste Management Cost Model for Policy Analysis

    Science.gov (United States)

    Barron, R. W.; Hill, M. C.

    2017-12-01

    Although integrated assessments of climate change policy have frequently identified nuclear energy as a promising alternative to fossil fuels, these studies have often treated nuclear waste disposal very simply. Simple assumptions about nuclear waste are problematic because they may not be adequate to capture relevant costs and uncertainties, which could result in suboptimal policy choices. Modeling nuclear waste management costs is a cross-disciplinary, multi-scale problem that involves economic, geologic and environmental processes that operate at vastly different temporal scales. Similarly, the climate-related costs and benefits of nuclear energy are dependent on environmental sensitivity to CO2 emissions and radiation, nuclear energy's ability to offset carbon emissions, and the risk of nuclear accidents, factors which are all deeply uncertain. Alternative value systems further complicate the problem by suggesting different approaches to valuing intergenerational impacts. Effective policy assessment of nuclear energy requires an integrated approach to modeling nuclear waste management that (1) bridges disciplinary and temporal gaps, (2) supports an iterative, adaptive process that responds to evolving understandings of uncertainties, and (3) supports a broad range of value systems. This work develops the Nuclear Waste Management Cost Model (NWMCM). NWMCM provides a flexible framework for evaluating the cost of nuclear waste management across a range of technology pathways and value systems. We illustrate how NWMCM can support policy analysis by estimating how different nuclear waste disposal scenarios developed using the NWMCM framework affect the results of a recent integrated assessment study of alternative energy futures and their effects on the cost of achieving carbon abatement targets. Results suggest that the optimism reflected in previous works is fragile: Plausible nuclear waste management costs and discount rates appropriate for intergenerational cost

  15. MODELING MONETARY POLICY RULES IN THE MENACOUNTRIES: ISSUES AND EVIDENCE

    Directory of Open Access Journals (Sweden)

    Mohamad Husam Helmi

    2011-07-01

    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.

  16. Performance of third-trimester ultrasound for prediction of small-for-gestational-age neonates and evaluation of contingency screening policies.

    Science.gov (United States)

    Souka, A P; Papastefanou, I; Pilalis, A; Michalitsi, V; Kassanos, D

    2012-05-01

    third trimester according to the risk estimated by a first-trimester prediction model yielded a detection rate of 79% for a 25% screen-positive rate. Third-trimester ultrasound is effective in screening for SGA in uncomplicated pregnancies. The use of a contingency screening policy can reduce the need for unnecessary examinations. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.

  17. Modeling expectations in agent-based models: an application to central bank's communication and monetary policy

    NARCIS (Netherlands)

    Salle, I.L.

    2015-01-01

    Expectations play a major role in macroeconomic dynamics, especially regarding the conduct of monetary policy. Yet, modeling the interplay between communication, expectations and aggregate outcomes remains a challenging task, mainly because this requires deviation from the paradigm of rational

  18. National Environmental Policy Act guidance: A model process

    International Nuclear Information System (INIS)

    Angle, B.M.; Lockhart, V.A.T.; Sema, B.; Tuott, L.C.; Irving, J.S.

    1995-04-01

    The ''Model National Environmental Policy Act (NEPA) Process'' includes: References to regulations, guidance documents, and plans; training programs; procedures; and computer databases. Legislative Acts and reference documents from Congress, US Department of Energy, and Lockheed Idaho Technologies Company provide the bases for conducting NEPA at the Idaho National Engineering Laboratory (INEL). Lockheed Idaho Technologies Company (LITCO) NEPA / Permitting Department, the Contractor Environmental Organization (CEO) is responsible for developing and maintaining LITCO NEPA and permitting policies, guidance, and procedures. The CEO develops procedures to conduct environmental evaluations based on NEPA, Council on Environmental Quality (CEQ) regulations, and DOE guidance. This procedure includes preparation or support of environmental checklists, categorical exclusion determinations, environmental assessment determinations, environmental assessments, and environmental impact statements. In addition, the CEO uses this information to train personnel conducting environmental evaluations at the INEL. Streamlining these procedures fosters efficient use of resources, quality documents, and better decisions on proposed actions

  19. Performance of first-trimester combined test for Down syndrome in different maternal age groups: reason for adjustments in screening policy?

    NARCIS (Netherlands)

    Engels, Melanie A. J.; Heijboer, A. C.; Blankenstein, Marinus A.; van Vugt, John M. G.

    2011-01-01

    To evaluate the performance of the first-trimester combined test (FCT) in different maternal age groups and to discuss whether adjustments in screening policies should be made. In this retrospective study data (n = 26 274) from a fetal medicine center on FCT (maternal age, fetal NT, free β-human

  20. Physical activity and screen use policy and practices in childcare: results from a survey of early childhood education services in New Zealand.

    Science.gov (United States)

    Gerritsen, Sarah; Morton, Susan M B; Wall, Clare R

    2016-08-01

    To investigate written policies, equipment, strategies and barriers to children's activity in early childhood education settings, including participation in health promotion programs and reported time children spend in active play and using screens while in care. Cross-sectional online survey of licensed childcare services in Auckland and Waikato. Policies were scored using a validated tool (WellCCAT-NZ). Results were analysed using descriptive statistics and multivariate regression. Managers, head teachers or similar from 237 services completed the survey (28% of invited services). Of these, 35% had a written activity policy; most policies scored low on the WellCCAT-NZ. Comprehensive and strongly worded policies were associated with a lower adult-to-child ratio (p=0.03, adjusted for ECE characteristics). No policies addressed screen use. Children were reported to have teacher-led activity 80 minutes/day, and child-led activity five hours/day (indoor and outdoor). Children watched television daily in 2% and weekly in 11% the services; and used computers daily in 11% and weekly in 22% of services. Fewer than half of services participated in health promotion programs with a physical activity component. Childcare services reported having adequate equipment, space and time for physical activity of children; however, there are low participation rates in activity programs and a notable absence of written policy. © 2016 Public Health Association of Australia.

  1. Termination of the leprosy isolation policy in the US and Japan : Science, policy changes, and the garbage can model

    Science.gov (United States)

    Sato, Hajime; Frantz, Janet E

    2005-01-01

    Background In both the US and Japan, the patient isolation policy for leprosy /Hansen's disease (HD) was preserved along with the isolation facilities, long after it had been proven to be scientifically unnecessary. This delayed policy termination caused a deprivation of civil liberties of the involuntarily confined patients, the fostering of social stigmas attached to the disease, and an inefficient use of health resources. This article seeks to elucidate the political process which hindered timely policy changes congruent with scientific advances. Methods Examination of historical materials, supplemented by personal interviews. The role that science played in the process of policy making was scrutinized with particular reference to the Garbage Can model. Results From the vantage of history, science remained instrumental in all period in the sense that it was not the primary objective for which policy change was discussed or intended, nor was it the principal driving force for policy change. When the argument arose, scientific arguments were employed to justify the patient isolation policy. However, in the early post-WWII period, issues were foregrounded and agendas were set as the inadvertent result of administrative reforms. Subsequently, scientific developments were more or less ignored due to concern about adverse policy outcomes. Finally, in the 1980s and 1990s, scientific arguments were used instrumentally to argue against isolation and for the termination of residential care. Conclusion Contrary to public expectations, health policy is not always rational and scientifically justified. In the process of policy making, the role of science can be limited and instrumental. Policy change may require the opening of policy windows, as a result of convergence of the problem, policy, and political streams, by effective exercise of leadership. Scientists and policymakers should be attentive enough to the political context of policies. PMID:15771781

  2. Termination of the leprosy isolation policy in the US and Japan : Science, policy changes, and the garbage can model

    Directory of Open Access Journals (Sweden)

    Frantz Janet E

    2005-03-01

    Full Text Available Abstract Background In both the US and Japan, the patient isolation policy for leprosy /Hansen's disease (HD was preserved along with the isolation facilities, long after it had been proven to be scientifically unnecessary. This delayed policy termination caused a deprivation of civil liberties of the involuntarily confined patients, the fostering of social stigmas attached to the disease, and an inefficient use of health resources. This article seeks to elucidate the political process which hindered timely policy changes congruent with scientific advances. Methods Examination of historical materials, supplemented by personal interviews. The role that science played in the process of policy making was scrutinized with particular reference to the Garbage Can model. Results From the vantage of history, science remained instrumental in all period in the sense that it was not the primary objective for which policy change was discussed or intended, nor was it the principal driving force for policy change. When the argument arose, scientific arguments were employed to justify the patient isolation policy. However, in the early post-WWII period, issues were foregrounded and agendas were set as the inadvertent result of administrative reforms. Subsequently, scientific developments were more or less ignored due to concern about adverse policy outcomes. Finally, in the 1980s and 1990s, scientific arguments were used instrumentally to argue against isolation and for the termination of residential care. Conclusion Contrary to public expectations, health policy is not always rational and scientifically justified. In the process of policy making, the role of science can be limited and instrumental. Policy change may require the opening of policy windows, as a result of convergence of the problem, policy, and political streams, by effective exercise of leadership. Scientists and policymakers should be attentive enough to the political context of policies.

  3. Tobacco Policies in Louisiana: Recommendations for Future Tobacco Control Investment from SimSmoke, a Policy Simulation Model.

    Science.gov (United States)

    Levy, David; Fergus, Cristin; Rudov, Lindsey; McCormick-Ricket, Iben; Carton, Thomas

    2016-02-01

    Despite the presence of tobacco control policies, Louisiana continues to experience a high smoking burden and elevated smoking-attributable deaths. The SimSmoke model provides projections of these health outcomes in the face of existing and expanded (simulated) tobacco control polices. The SimSmoke model utilizes population data, smoking rates, and various tobacco control policy measures from Louisiana to predict smoking prevalence and smoking-attributable deaths. The model begins in 1993 and estimates are projected through 2054. The model is validated against existing Louisiana smoking prevalence data. The most powerful individual policy measure for reducing smoking prevalence is cigarette excise tax. However, a comprehensive cessation treatment policy is predicted to save the most lives. A combination of tobacco control policies provides the greatest reduction in smoking prevalence and smoking-attributable deaths. The existing Louisiana excise tax ranks as one of the lowest in the country and the legislature is against further increases. Alternative policy measures aimed at lowering prevalence and attributable deaths are: cessation treatments, comprehensive smoke-free policies, and limiting youth access. These three policies have a substantial effect on smoking prevalence and attributable deaths and are likely to encounter more favor in the Louisiana legislature than increasing the state excise tax.

  4. Socio-psychological factors in the Expanded Health Belief Model and subsequent colorectal cancer screening.

    Science.gov (United States)

    Sohler, Nancy L; Jerant, Anthony; Franks, Peter

    2015-07-01

    CRC screening interventions tailored to the Expanded Health Belief Model (EHBM) socio-psychological factors have been developed, but the contributions of individual factors to screening outcomes are unclear. In observational analyses of data from a randomized intervention trial, we examined the independent associations of five EHBM factors - CRC screening knowledge, self-efficacy, stage of readiness, barriers, and discussion with a provider - with objectively measured CRC screening after one year. When all five factors were added simultaneously to a base model including other patient and visit characteristics, three of the factors were associated with CRC screening: self-efficacy (OR=1.32, p=0.001), readiness (OR=2.72, pmodel improved prediction of CRC screening (area under the curve) by 7.7%. Patient CRC screening self-efficacy, readiness, and discussion with a provider each independently predicted subsequent screening. Self-efficacy and readiness measures might be helpful in parsimoniously predicting which patients are most likely to engage in CRC screening. The importance of screening discussion with a provider suggests the potential value of augmenting patient-focused EHBM-tailored interventions with provider-focused elements. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  5. Prenatal maternal plasma DNA screening for cystic fibrosis: A computer modelling study of screening performance [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Robert W. Old

    2017-10-01

    Full Text Available Background: Prenatal cystic fibrosis (CF screening is currently based on determining the carrier status of both parents. We propose a new method based only on the analysis of DNA in maternal plasma. Methods: The method relies on the quantitative amplification of the CF gene to determine the percentage of DNA fragments in maternal plasma at targeted CF mutation sites that carry a CF mutation. Computer modelling was carried out to estimate the distributions of these percentages in pregnancies with and without a fetus affected with CF. This was done according to the number of DNA fragments counted and fetal fraction, using the 23 CF mutations recommended by the American College of Medical Genetics for parental carrier testing. Results: The estimated detection rate (sensitivity is 70% (100% of those detected using the 23 mutations, the false-positive rate 0.002%, and the odds of being affected given a positive screening result 14:1, compared with 70%, 0.12%, and 1:3, respectively, with current prenatal screening based on parental carrier testing. Conclusions: Compared with current screening practice based on parental carrier testing, the proposed method would substantially reduce the number of invasive diagnostic procedures (amniocentesis or chorionic villus sampling without reducing the CF detection rate. The expected advantages of the proposed method justify carrying out the necessary test development for use in a clinical validation study.

  6. Modeling and Recognizing Policy Conflicts with Resource Access Requests on Protected Health Information

    Directory of Open Access Journals (Sweden)

    Raik Kuhlisch

    2017-07-01

    Full Text Available This article discusses potential clashes between different types of security policies that regulate resource access requests on clinical patient data in hospitals by employees. Attribute-based Access Control (ABAC is proposed as a proper means for such regulation. A proper representation of ABAC policies must include a handling of policy attributes among different policy types. In this article, we propose a semantic policy model with predefined policy conflict categories. A conformance verification function detects erroneous, clashing or mutually susceptible rules early during the policy planning phase. The model and conflicts are used in a conceptual application environment and evaluated in a technical experiment during an interoperability test event.

  7. Transboundary air pollution in Asia: Model development and policy implications

    Science.gov (United States)

    Holloway, Tracey

    2001-12-01

    This work investigates transboundary air pollution in Asia through atmospheric modeling and public policy analysis. As an example of models actively shaping environmental policy, the Convention on Long-Range Transboundary Air Pollution in Europe (LRTAP) is selected as a case study. The LRTAP Convention is the only mulit- lateral air pollution agreement to date, and results from the RAINS integrated assessment model were heavily used to calculate nationally differentiated emission ceilings. Atmospheric chemistry and transport are included in RAINS through the use of transfer coefficients (or ``source-receptor relationships'') relating pollutant transfer among European nations. Following past work with ATMOS to simulate sulfur species in Asia, here ATMOS is developed to include odd-nitrogen. Fitting with the linear structure of ATMOS and the emphasis on computational efficiency, a simplified chemical scheme developed for use in the NOAA Geophysical Fluid Dynamics Laboratory Global Chemical Transport Model (GFDL GCTM) is adopted. The method solves for the interconversions between NOx, HNO3, and PAN based on five reaction rates stored in look-up tables. ATMOS is used to calculate source-receptor relationships for Asia. Significant exchange of NOy occurs among China, North and South Korea, and Japan. On an annual average basis, China contributes 18% to Japan's total nitrate deposition, 46% to North Korea, and 26% to South Korea. Nitrate deposition is an important component of acidification (along with sulfate deposition), contributing 30-50% to the acid burden over most of Japan, and more than 50% to acid deposition in southeast Asia, where biomass burning emits high levels of NOx. In evaluating the policy-relevance of results from the ATMOS model, four factors are taken into account: the uncertainty and limitations of ATMOS, the environmental concerns facing Asia, the current status of the scientific community in relation to regional air pollution in the region, and

  8. The sociocultural health behavioral model and disparities in colorectal cancer screening among Chinese Americans.

    Science.gov (United States)

    Ma, Grace X; Wang, Min Qi; Ma, Xiang S; Kim, Giyeon; Toubbeh, Jamil; Shive, Steven

    2013-01-01

    The purpose of this study was to validate a Sociocultural Health Behavior Model using a structural equation analysis to determine the direction and magnitude of the interdependence of model components in relation to health behavior associated with colorectal cancer (CRC) screening among Chinese Americans. A cross-sectional design included a sample of 311 Chinese American men and women age 50 and older. The initial step involved use of confirmatory factor analysis which included the following variables: access/satisfaction with health care, enabling, predisposing, cultural, and health belief factors. Structural equation modeling analyses were conducted on factors for CRC screening. Education and health insurance status were significantly related to CRC screening. Those with less than a high school education and without health insurance were more likely to be "never screened" for CRC than those having more education and health insurance. The path analysis findings also lend support for components of the Sociocultural Health Belief Model and indicated that there was a positive and significant relationship between CRC screening and the enabling factors, between cultural factors and predisposing, enabling, and access/satisfaction with health care factors and between enabling factors and access/satisfaction with health care. The model highlights the significance that sociocultural factors play in relation to CRC screening and reinforced the need to assist Chinese with poor English proficiency in translation and awareness of the importance of CRC screening. The use of community organizations may play a role in assisting Chinese to enhance colorectal cancer screening rates.

  9. Effects of screening and partner notification on Chlamydia positivity in the United States: a modeling study.

    Science.gov (United States)

    Kretzschmar, Mirjam; Satterwhite, Catherine; Leichliter, Jami; Berman, Stuart

    2012-05-01

    Model impact of increasing screening and partner notification (PN) on chlamydia positivity. We used a stochastic simulation model describing pair formation and dissolution in an age-structured heterosexual population. The model accounts for steady, casual, and concurrent partnerships and a highly sexually active core group. The model used existing sexual behavior data from the United States and was validated using chlamydia positivity data from Region X (Alaska, Idaho, Oregon, Washington). A screening program with a coverage rate of 20% was implemented among women aged 15 to 24 years. After 10 years, we increased screening coverage to 35%, 50%, and 65% and partner treatment rates from 20% to 40% and 55%. Finally, we included male screening (aged 15-24, screening coverage: 20% and 35%, partner treatment: 25% and 40%). We analyzed the effects on chlamydia positivity in women and the frequency of reinfection 6 months after treatment. The model described the decline in positivity observed from 1988 to 1997 in Region X, given screening coverage of 20% and a 25% partner treatment rate. Increasing screening coverage from 35% to 65% resulted in incremental decreases in positivity as did increasing the PN rate; a 23% reduction in positivity was achieved by either increasing screening by 3-fold or PN by 2-fold. Adding male screening to the program had less impact than increasing screening coverage or PN among women. Increased PN and treatment reduced reinfection rates considerably. Increasing efforts in PN may contribute at least as much to control of chlamydia infection as increasing screening coverage rates.

  10. Risk-Screening Environmental Indicators (RSEI)

    Data.gov (United States)

    U.S. Environmental Protection Agency — EPA’s Risk-Screening Environmental Indicators (RSEI) is a geographically-based model that helps policy makers and communities explore data on releases of toxic...

  11. Down Syndrome Health Screening--The Fife Model

    Science.gov (United States)

    Jones, Jill; Hathaway, Dorothy; Gilhooley, Mary; Leech, Amanda; MacLeod, Susan

    2010-01-01

    People with Down syndrome have a greater risk of developing a range of health problems, including cardiac problems, thyroid disorders, sensory impairments, reduced muscle tone (hypotonia) and Alzheimer's disease. Despite this increased risk, regular screening is not typically offered to individuals with Down syndrome. A multidisciplinary health…

  12. High-throughput screening, predictive modeling and computational embryology

    Science.gov (United States)

    High-throughput screening (HTS) studies are providing a rich source of data that can be applied to profile thousands of chemical compounds for biological activity and potential toxicity. EPA’s ToxCast™ project, and the broader Tox21 consortium, in addition to projects worldwide,...

  13. High-throughput screening, predictive modeling and computational embryology - Abstract

    Science.gov (United States)

    High-throughput screening (HTS) studies are providing a rich source of data that can be applied to chemical profiling to address sensitivity and specificity of molecular targets, biological pathways, cellular and developmental processes. EPA’s ToxCast project is testing 960 uniq...

  14. Steroidogenesis in vitro : towards relevant models for endocrine disruptor screening

    NARCIS (Netherlands)

    Roelofs, M.J.E.

    2016-01-01

    Starting our search for in vitro alternative methods to screen for steroidogenesis toxicity, we focused on the effects of (suggested) endocrine disrupting compounds (EDCs) on cytochrome P450 17 (CYP17) enzyme activity. CYP17 is responsible for conversion of progestagens to dehydroepiandrosterone

  15. Model for the brightness uniformity of fluorescence screen of image intensifier

    Science.gov (United States)

    Qiu, YaFeng; Chang, BenKang; Qian, YunSheng; Fu, RongGuo; Gao, Youtang; Si, Tian

    2007-01-01

    The three elements of photoelectrical cathode, microchannel plate and fluorescence screen are important parts to imaging quality of low light and ultraviolet Image intensifier. To do research and analysis work on the Fluorescence screen parameter testing have practical significance to the understanding of the performance of fluorescence screen and then can help to know where improvement should be made and then achieve a best performance entire tube, This article mainly introduce the testing theory of the brightness uniformity of fluorescence screen of Image Intensifier and how to build a mathematic model.

  16. Modeling the impact of population screening on breast cancer mortality in the United States.

    Science.gov (United States)

    Mandelblatt, Jeanne S; Cronin, Kathleen A; Berry, Donald A; Chang, Yaojen; de Koning, Harry J; Lee, Sandra J; Plevritis, Sylvia K; Schechter, Clyde B; Stout, Natasha K; van Ravesteyn, Nicolien T; Zelen, Marvin; Feuer, Eric J

    2011-10-01

    Optimal US screening strategies remain controversial. We use six simulation models to evaluate screening outcomes under varying strategies. The models incorporate common data on incidence, mammography characteristics, and treatment effects. We evaluate varying initiation and cessation ages applied annually or biennially and calculate mammograms, mortality reduction (vs. no screening), false-positives, unnecessary biopsies and over-diagnosis. The lifetime risk of breast cancer death starting at age 40 is 3% and is reduced by screening. Screening biennially maintains 81% (range 67% to 99%) of annual screening benefits with fewer false-positives. Biennial screening from 50-74 reduces the probability of breast cancer death from 3% to 2.3%. Screening annually from 40 to 84 only lowers mortality an additional one-half of one percent to 1.8% but requires substantially more mammograms and yields more false-positives and over-diagnosed cases. Decisions about screening strategy depend on preferences for benefits vs. potential harms and resource considerations. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Type and screen policy in the blood bank: Is AHG cross-match still required? A study at a multispecialty corporate hospital in India

    Directory of Open Access Journals (Sweden)

    Pathak Sangeeta

    2011-01-01

    Full Text Available Background: Antibodies against only about 25-28 blood group antigens are known to cause hemolytic reactions (HTRs, and red cell antibody screening should detect such clinically significant antibodies. An extension of the antibody screening test is the ′type and screen′ done to detect clinically significant antibodies, omiting the anti-human globulin (AHG cross-match. Aim: The aim of this study was to find out if the type and screen procedure is a safe method for pre-transfusion testing when compared to the AHG cross-match currently in use in India. Materials and Methods: We evaluated data from 45373 patients for whom a total of 61668 units of packed red blood cells (PRBC were cross-matched in the AHG phase using DiaMed; ID cards. An antibody screen was carried out in all the patients using the DiaMed; ID-DiaCell I+II+III. The AHG cross-match was also carried out for all recipients, irrespective of the result of the antibody screen. The results were compared to see if there were any cases where the antibody screening was negative but the AHG cross-match showed incompatibility. Results: Not a single case was found where the antibody screen was negative and AHG cross-match showed incompatibility. In 68 cases the antibody screening was positive. Out of the 68 cases, AHG cross-match was incompatible with at least one unit of PRBC in 41 cases. Conclusion: The screening cell panel adequately detected the clinically significant antibodies in the Indian population in our study. The type and screen policy can be safe, efficient, cost-effective, and beneficial to the transfusion service in India.

  18. Econometric Model of Rice Policy Based On Presidential Instruction

    Science.gov (United States)

    Abadi Sembiring, Surya; Hutauruk, Julia

    2018-01-01

    The objective of research is to build an econometric model based on Presidential Instruction rice policy. The data was monthly time series from March 2005 to September 2009. Rice policy model specification using simultaneous equation, consisting of 14 structural equations and four identity equation, which was estimated using Two Stages Least Squares (2SLS) method. The results show that: (1) an increase of government purchasing price of dried harvest paddy has a positive impact on to increase in total rice production and community rice stock, (2) an increase community rice stock lead to decrease the rice imports, (3) an increase of the realization of the distribution of subsidized ZA fertilizers and the realization of the distribution of subsidized NPK fertilizers has a positive impact on to increase in total rice production and community rice stock and to reduce rice imports, (4) the price of the dried harvest paddy is highly responsive to the water content of dried harvest paddy both the short run and long run, (5) the quantity of rice imported is highly responsive to the imported rice price, both short run and long run.

  19. Assessing policies towards sustainable transport in Europe: an integrated model

    International Nuclear Information System (INIS)

    Zachariadis, Theodoros

    2005-01-01

    A transport simulation and forecast model is presented, which is designed for the assessment of policy options aiming to achieve sustainability in transportation. Starting from a simulation of the economic behaviour of consumers and producers within a microeconomic optimisation framework and the resulting calculation of the modal split, the allocation of the vehicle stock into vintages and technological groups is modelled. In a third step, a technology-oriented algorithm, which incorporates the relevant state-of-the-art knowledge in Europe, calculates emissions of air pollutants and greenhouse gases as well as appropriate indicators for traffic congestion, noise and road accidents. The paper outlines the methodology and the basic data sources used in connection with work done so far in Europe, presents the outlook according to a 'reference case' run for the 15 current European Union Member States up to 2030, displays aggregate results from a number of alternative scenarios and outlines elements of future work

  20. Modelling issues on climate change policies. A discussion of the GTAP-E model

    International Nuclear Information System (INIS)

    Kremers, H.; Nijkamp, P.; Wang, Shunli

    2000-01-01

    Ater the Kyoto agreements the need has arisen to trace the implications of various international environmental strategies. In this paper, we discuss relevant modelling issues of incorporating important environmental policy measures in one of the popular applied general equilibrium models for international trade, the so-called GTAP model. Special attention is paid to an extended version, the GTAP-E (Global Trade Analysis Project - Energy) by addressing the question how to include the widely discussed instruments of International Emission Trading, Joint Implementation, and Clean Development Mechanisms. The paper will be concluded with some policy issues. 10 refs

  1. Independent screening for single-index hazard rate models with ultrahigh dimensional features

    DEFF Research Database (Denmark)

    Gorst-Rasmussen, Anders; Scheike, Thomas

    2013-01-01

    on performance. An iterative variant of the method is also described which combines screening with penalized regression to handle more complex feature covariance structures. The methodology is evaluated through simulation studies and through application to a real gene expression data set.......In data sets with many more features than observations, independent screening based on all univariate regression models leads to a computationally convenient variable selection method. Recent efforts have shown that, in the case of generalized linear models, independent screening may suffice...... to capture all relevant features with high probability, even in ultrahigh dimension. It is unclear whether this formal sure screening property is attainable when the response is a right-censored survival time. We propose a computationally very efficient independent screening method for survival data which...

  2. FOOTPRINT: A Screening Model for Estimating the Area of a Plume Produced From Gasoline Containing Ethanol

    Science.gov (United States)

    FOOTPRINT is a screening model used to estimate the length and surface area of benzene, toluene, ethylbenzene, and xylene (BTEX) plumes in groundwater, produced from a gasoline spill that contains ethanol.

  3. A globally applicable screening model for detecting individuals with undiagnosed diabetes

    DEFF Research Database (Denmark)

    Vistisen, Dorte; Lee, Crystal M Y; Colagiuri, Stephen

    2012-01-01

    Current risk scores for undiagnosed diabetes are additive in structure. We sought to derive a globally applicable screening model based on established non-invasive risk factors for diabetes but with a more flexible structure....

  4. Evaluating predictive modeling's potential to improve teleretinal screening participation in urban safety net clinics.

    Science.gov (United States)

    Ogunyemi, Omolola; Teklehaimanot, Senait; Patty, Lauren; Moran, Erin; George, Sheba

    2013-01-01

    Screening guidelines for diabetic patients recommend yearly eye examinations to detect diabetic retinopathy and other forms of diabetic eye disease. However, annual screening rates for retinopathy in US urban safety net settings remain low. Using data gathered from a study of teleretinal screening in six urban safety net clinics, we assessed whether predictive modeling could be of value in identifying patients at risk of developing retinopathy. We developed and examined the accuracy of two predictive modeling approaches for diabetic retinopathy in a sample of 513 diabetic individuals, using routinely available clinical variables from retrospective medical record reviews. Bayesian networks and radial basis function (neural) networks were learned using ten-fold cross-validation. The predictive models were modestly predictive with the best model having an AUC of 0.71. Using routinely available clinical variables to predict patients at risk of developing retinopathy and to target them for annual eye screenings may be of some usefulness to safety net clinics.

  5. Optimal healthcare decision making under multiple mathematical models: application in prostate cancer screening.

    Science.gov (United States)

    Bertsimas, Dimitris; Silberholz, John; Trikalinos, Thomas

    2018-03-01

    Important decisions related to human health, such as screening strategies for cancer, need to be made without a satisfactory understanding of the underlying biological and other processes. Rather, they are often informed by mathematical models that approximate reality. Often multiple models have been made to study the same phenomenon, which may lead to conflicting decisions. It is natural to seek a decision making process that identifies decisions that all models find to be effective, and we propose such a framework in this work. We apply the framework in prostate cancer screening to identify prostate-specific antigen (PSA)-based strategies that perform well under all considered models. We use heuristic search to identify strategies that trade off between optimizing the average across all models' assessments and being "conservative" by optimizing the most pessimistic model assessment. We identified three recently published mathematical models that can estimate quality-adjusted life expectancy (QALE) of PSA-based screening strategies and identified 64 strategies that trade off between maximizing the average and the most pessimistic model assessments. All prescribe PSA thresholds that increase with age, and 57 involve biennial screening. Strategies with higher assessments with the pessimistic model start screening later, stop screening earlier, and use higher PSA thresholds at earlier ages. The 64 strategies outperform 22 previously published expert-generated strategies. The 41 most "conservative" ones remained better than no screening with all models in extensive sensitivity analyses. We augment current comparative modeling approaches by identifying strategies that perform well under all models, for various degrees of decision makers' conservativeness.

  6. Development and Validation of Risk Models to Select Ever-Smokers for CT Lung Cancer Screening.

    Science.gov (United States)

    Katki, Hormuzd A; Kovalchik, Stephanie A; Berg, Christine D; Cheung, Li C; Chaturvedi, Anil K

    2016-06-07

    The US Preventive Services Task Force (USPSTF) recommends computed tomography (CT) lung cancer screening for ever-smokers aged 55 to 80 years who have smoked at least 30 pack-years with no more than 15 years since quitting. However, selecting ever-smokers for screening using individualized lung cancer risk calculations may be more effective and efficient than current USPSTF recommendations. Comparison of modeled outcomes from risk-based CT lung-screening strategies vs USPSTF recommendations. Empirical risk models for lung cancer incidence and death in the absence of CT screening using data on ever-smokers from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO; 1993-2009) control group. Covariates included age; education; sex; race; smoking intensity, duration, and quit-years; body mass index; family history of lung cancer; and self-reported emphysema. Model validation in the chest radiography groups of the PLCO and the National Lung Screening Trial (NLST; 2002-2009), with additional validation of the death model in the National Health Interview Survey (NHIS; 1997-2001), a representative sample of the United States. Models were applied to US ever-smokers aged 50 to 80 years (NHIS 2010-2012) to estimate outcomes of risk-based selection for CT lung screening, assuming screening for all ever-smokers, yield the percent changes in lung cancer detection and death observed in the NLST. Annual CT lung screening for 3 years beginning at age 50 years. For model validity: calibration (number of model-predicted cases divided by number of observed cases [estimated/observed]) and discrimination (area under curve [AUC]). For modeled screening outcomes: estimated number of screen-avertable lung cancer deaths and estimated screening effectiveness (number needed to screen [NNS] to prevent 1 lung cancer death). Lung cancer incidence and death risk models were well calibrated in PLCO and NLST. The lung cancer death model calibrated and discriminated well for US

  7. Evaluation of parameters of color profile models of LCD and LED screens

    Science.gov (United States)

    Zharinov, I. O.; Zharinov, O. O.

    2017-12-01

    The purpose of the research relates to the problem of parametric identification of the color profile model of LCD (liquid crystal display) and LED (light emitting diode) screens. The color profile model of a screen is based on the Grassmann’s Law of additive color mixture. Mathematically the problem is to evaluate unknown parameters (numerical coefficients) of the matrix transformation between different color spaces. Several methods of evaluation of these screen profile coefficients were developed. These methods are based either on processing of some colorimetric measurements or on processing of technical documentation data.

  8. Development and Application of Econometric Models for Forecasting and Analysis of Monetary Policy Scenarios

    OpenAIRE

    Malugin, Vladimir; Demidenko , Mikhail; Kalechits, Dmitry; Miksjuk , Alexei; Tsukarev , Taras

    2009-01-01

    A system of econometric models designed for forecasting target monetary indicators as well as conducting monetary policy scenarios analysis is presented. The econometric models integrated in the system are represented in the error correction form and are interlinked by means of monetary policy instruments variables, common exogenous variables characterizing external shocks, and monetary policy target endogenous variables. Forecast accuracy estimates and monetary policy analysis results are pr...

  9. A UK guide to intake fish-screening regulations, policy and best practice with particular reference to hydroelectric power schemes

    Energy Technology Data Exchange (ETDEWEB)

    Turnpenny, A.W.H.; Struthers, G.; Hanson, P.

    1998-07-01

    A review of fish screening regulations in England, Wales, Scotland, and Northern Ireland is presented, and a summary of findings on screening legislation is given. The views of hydroelectric scheme developers, owners and operators are considered, and recommendations including the development of a risk assessment procedure are discussed. Fish screening technology, bypasses and other escape routes, and common fault in screen design and operation are examined, and guidance to Best Practice is given. (UK)

  10. Application of system dynamics on nuclear policy model

    International Nuclear Information System (INIS)

    An, N. S.; Kim, J. C.; Kim, D. W.; Kang, S. C.

    2000-01-01

    A system dynamics model for a nuclear energy policy in Korea (SIMNEP) was developed to analyze the Korea nuclear system and to predict the influence of the nuclear energy policy in the future. Two cases were analyzed using SIMNEP. The first case is to see the effect of the occurrence of severe nuclear accident in foreign country on the Korean government support. In the beginning, the Korean government support drops but jump up to the higher value than normal support due to the intelligentsia support influenced by the delay time of perception. Then, the national government support converges to the normal support. This turns out that the intelligentsia support plays a major role in increasing the government support. The second case is to see the effect of prior efforts on the foreign factors and/or on domestic factors on the U.S. government support. In the short term, effort on the U.S. government is more effective to increase U.S. government support but in the long term (about after 5 years), efforts on the domestic factors influence on the U.S. government support more than efforts on the foreign factors. The Korean government counter reaction among the influencing factors on the U.S. government support plays a major role to explain this result

  11. A model for policy analysis of the greenhouse effect

    International Nuclear Information System (INIS)

    Hope, C.

    1992-01-01

    This paper describes the PAGE model (for Policy Analysis of the Greenhouse Effect), developed by Cambridge Decision Analysts for the Directorate general for Environment, Nuclear Safety and Civil Protection of the Commission of the European Communities. The rest of this section describes the motivation for developing PAGE; it is followed by sections outlining the features of PAGE, explaining its structure in more detail, and reporting some of the uses to which it is being put. The current consensus is that unchecked emissions of greenhouse gases will lead to a rise in global mean temperature. The causal chain from emissions to temperature is complex, and current estimates give a range of 2 - 5 deg C for the temperature rise by the year 2100 if no specific actions are taken to control emissions. The damage that a global temperature rise of a few degrees over a century would cause is also not well known. Some influential groups are sufficiently alarmed to have called for global agreements to stabilize or reduce the emissions of greenhouse gases. Others claim that the costs of doing so would not be justified, and that adapting to a changed climate would be the best policy. Negotiations are further complicated by the global nature of the problem; if a country, or even a major trading block such as the European Community, decided to control emissions of a greenhouse gas, some of the benefit would be gained in other parts of the world that have not shared in the cost of control. 12 refs., 6 figs

  12. Early detection of idiopathic scoliosis - analysis of three screening models.

    Science.gov (United States)

    Kowalski, Ireneusz M; Dwornik, Michał; Lewandowski, Roman; Pierożyński, Bogusław; Raistenskis, Juozas; J Krzych, Łukasz; Kiebzak, Wojciech

    2015-10-12

    The prevalence of lateral curvatures of the spine ranges from 0.3% to 15.3% in the general population. The aim of the study was to develop and compare three different screening tests for idiopathic scoliosis (IS) with respect to their effectiveness and costs. The Delphi method was used to assess the efficacy of each screening algorithm in detecting IS in the population. An economic analysis was also performed. Diagnostic Algorithm 1 for IS comprised a screening examination performed by nurses and a general practitioner (GP) with verification by specialists. The unit cost of carrying out diagnostic work-up for IS in Algorithm 1 was €94 per child. The second algorithm involved the use of the moiré computer method, followed by verification by a specialist. The lower unit cost of €86 per child of diagnostic work-up according to Algorithm 2 was due to fewer stages compared to Algorithm 1. The highest effectiveness with the highest costs were found for the third algorithm, with only one stage, a specialist's consultation (cost €153 per child). The number of stages in an algorithm does not correlate positively with its efficacy or cost. The recommended scheme is Algorithm 3, where children are examined by rehabilitation specialists or a physiotherapist using a scoliometer and an inclinometer. The use of the apparently most expensive scheme (Algorithm 3) should result in lowering the costs of treatment of established idiopathic scoliosis and, in the long term, prove to be the most cost-effective solution for the health care system.

  13. Six challenges in modelling for public health policy

    Directory of Open Access Journals (Sweden)

    C.J.E. Metcalf

    2015-03-01

    Full Text Available The World Health Organisation's definition of public health refers to all organized measures to prevent disease, promote health, and prolong life among the population as a whole (World Health Organization, 2014. Mathematical modelling plays an increasingly important role in helping to guide the most high impact and cost-effective means of achieving these goals. Public health programmes are usually implemented over a long period of time with broad benefits to many in the community. Clinical trials are seldom large enough to capture these effects. Observational data may be used to evaluate a programme after it is underway, but have limited value in helping to predict the future impact of a proposed policy. Furthermore, public health practitioners are often required to respond to new threats, for which there is little or no previous data on which to assess the threat. Computational and mathematical models can help to assess potential threats and impacts early in the process, and later aid in interpreting data from complex and multifactorial systems. As such, these models can be critical tools in guiding public health action. However, there are a number of challenges in achieving a successful interface between modelling and public health. Here, we discuss some of these challenges.

  14. Six challenges in modelling for public health policy.

    Science.gov (United States)

    Metcalf, C J E; Edmunds, W J; Lessler, J

    2015-03-01

    The World Health Organisation's definition of public health refers to all organized measures to prevent disease, promote health, and prolong life among the population as a whole (World Health Organization, 2014). Mathematical modelling plays an increasingly important role in helping to guide the most high impact and cost-effective means of achieving these goals. Public health programmes are usually implemented over a long period of time with broad benefits to many in the community. Clinical trials are seldom large enough to capture these effects. Observational data may be used to evaluate a programme after it is underway, but have limited value in helping to predict the future impact of a proposed policy. Furthermore, public health practitioners are often required to respond to new threats, for which there is little or no previous data on which to assess the threat. Computational and mathematical models can help to assess potential threats and impacts early in the process, and later aid in interpreting data from complex and multifactorial systems. As such, these models can be critical tools in guiding public health action. However, there are a number of challenges in achieving a successful interface between modelling and public health. Here, we discuss some of these challenges. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  15. The duopoly policy in the Brazilian model of telecommunications reform

    Directory of Open Access Journals (Sweden)

    César Mattos

    2004-09-01

    Full Text Available One of the important characteristics of the Brazilian Model of Telecommunications Reform (BMTR was the adoption of a duopoly policy, constraining the entry of new players in the wire segment in the transitional phase until free competition in 2002. This policy was also used in the reform experience of the United Kingdom in telecommunications in the 80's. The theoretical explanations behind this kind of policy are not strong enough to justify the duopoly policy in telecommunications. The most plausible idea rests on the prominent role conferred to privatization revenues in the design of the reform as a means of helping the efforts to consolidate price stabilization in the country. We introduce a model with the trade-offs between competition, duplication of fixed costs and privatization revenues. Despite the importance of fixed costs in the objective function of the regulator, we show that the privatization revenue target is the aspect, which justifies the imposition of entry constraints. The British experience shows that the sacrifice of this kind of policy regarding efficiency in the long run can be substantial.Uma das características mais importantes do Modelo Brasileiro de Reforma das Telecomunicações foi a adoção de uma política de duopólio, restringindo a entrada de novas empresas no segmento de telefonia fixa durante a fase de transição até a livre concorrência a ser adotada a partir de 2002. Essa política foi também utilizada na experiência de reforma das telecomunicações ocorrida no Reino Unido na década de 80. As explicações teóricas para justificar a adoção deste tipo de política não são satisfatórias o suficiente para justificar a política de duopólio como prescrição de política nas telecomunicações. A idéia mais plausível se baseia no papel proeminente conferido às receitas de privatização no desenho da reforma como forma de auxiliar os esforços de consolidação da estabilização de preços no

  16. The Dutch sustainable building policy: A model for developing countries?

    Energy Technology Data Exchange (ETDEWEB)

    Melchert, Luciana [Faculty of Architecture and Urbanism, University of Sao Paulo, Rua do Lago, 876, CEP 05508.900, Sao Paulo SP (Brazil)

    2007-02-15

    This article explores the institutionalization of environmental policies in the Dutch building sector and the applicability of the current model to developing countries. First, it analyzes the transition of sustainable building practices in the Netherlands from the 1970s until today, exploring how these were originally embedded in a discourse on 'de-modernization', which attempted to improve the environmental performance of building stocks by means of self-sufficient technologies, whereas nowadays they adopt a framework of 'ecological modernization', with integrative approaches seeking to improve the environmental performance of building stocks through more efficient-rather than self-sufficient-technologies. The study subsequently shows how the current Dutch sustainable building framework has thereby managed to achieve a pragmatic and widely accepted rationale, which can serve to orient the ecological restructuring of building stocks in developing countries. (author)

  17. Clearing the air. Air quality modelling for policy support

    NARCIS (Netherlands)

    Hendriks, C.

    2017-01-01

    The studies presented in this thesis were performed to provide policy makers with more accurate information about the sources of air pollution and the possible consequences of future developments on air quality. This enables policy makers to make better informed decisions when formulating policies

  18. A Dynamic Linear Modeling Approach to Public Policy Change

    DEFF Research Database (Denmark)

    Loftis, Matthew; Mortensen, Peter Bjerre

    2017-01-01

    policy. The paper offers a detailed exposition of the DLM approach and illustrates its usefulness with a time series analysis of U.S. defense policy from 1957-2010. The results point the way for a new attention to dynamics in the policy process and the paper concludes with a discussion of how...

  19. The effect of omitting an early population-based vision screen in the Netherlands: A micro-simulation model approach.

    Science.gov (United States)

    Sloot, F; Heijnsdijk, Eam; Groenewoud, J H; Goudsmit, F; Steyerberg, E W; de Koning, H J; Simonsz, H J

    2017-09-01

    Objective To estimate the effect of omitting an individual screen from a child vision screening programme on the detection of amblyopia in the Netherlands. A previous study (Rotterdam Amblyopia Screening Effectiveness Study) suggested that the three screens carried out between 6 and 24 months contributed little. Methods We developed a micro-simulation model that approximated the birth-cohort data from the previous study, in which 2964 children had completed follow-up at age 7, and 100 amblyopia cases were detected. Detailed data on screens, referrals, and orthoptic follow-up, including the cause of amblyopia, were available. The model predicted the number of amblyopia cases detected for each screen and for the entire screening programme, and the effect of omitting screens. Incidence curves for all types of amblyopia caused by strabismus, refractive anomalies or by both were estimated by approximation of the observational data, in conjunction with experts' estimations and the literature. Results We calculated mean actual sensitivity per screen per type of amblyopia, and the effect per screen. Screening at 24 months was found to be least effective. The impact on the screening programme, estimated by summing the effectiveness per screen, omitting the 24-month screen, was a reduction of 3.4% (57 vs. 59 cases) in the number of detected cases of amblyopia at age 5. Conclusion The effectiveness of the Dutch vision screening programme would hardly be affected by omission of the 24-month screening examination. A disinvestment study is warranted.

  20. Dissolving decision making? Models and their roles in decision-making processes and policy at large.

    Science.gov (United States)

    Zeiss, Ragna; van Egmond, Stans

    2014-12-01

    This article studies the roles three science-based models play in Dutch policy and decision making processes. Key is the interaction between model construction and environment. Their political and scientific environments form contexts that shape the roles of models in policy decision making. Attention is paid to three aspects of the wider context of the models: a) the history of the construction process; b) (changes in) the political and scientific environments; and c) the use in policy processes over longer periods of time. Models are more successfully used when they are constructed in a stable political and scientific environment. Stability and certainty within a scientific field seems to be a key predictor for the usefulness of models for policy making. The economic model is more disputed than the ecology-based model and the model that has its theoretical foundation in physics and chemistry. The roles models play in policy processes are too complex to be considered as straightforward technocratic powers.

  1. Cost-Effectiveness of a Community Pharmacist-Led Sleep Apnea Screening Program - A Markov Model.

    Directory of Open Access Journals (Sweden)

    Clémence Perraudin

    Full Text Available Despite the high prevalence and major public health ramifications, obstructive sleep apnea syndrome (OSAS remains underdiagnosed. In many developed countries, because community pharmacists (CP are easily accessible, they have been developing additional clinical services that integrate the services of and collaborate with other healthcare providers (general practitioners (GPs, nurses, etc.. Alternative strategies for primary care screening programs for OSAS involving the CP are discussed.To estimate the quality of life, costs, and cost-effectiveness of three screening strategies among patients who are at risk of having moderate to severe OSAS in primary care.Markov decision model.Published data.Hypothetical cohort of 50-year-old male patients with symptoms highly evocative of OSAS.The 5 years after initial evaluation for OSAS.Societal.Screening strategy with CP (CP-GP collaboration, screening strategy without CP (GP alone and no screening.Quality of life, survival and costs for each screening strategy.Under almost all modeled conditions, the involvement of CPs in OSAS screening was cost effective. The maximal incremental cost for "screening strategy with CP" was about 455€ per QALY gained.Our results were robust but primarily sensitive to the treatment costs by continuous positive airway pressure, and the costs of untreated OSAS. The probabilistic sensitivity analysis showed that the "screening strategy with CP" was dominant in 80% of cases. It was more effective and less costly in 47% of cases, and within the cost-effective range (maximum incremental cost effectiveness ratio at €6186.67/QALY in 33% of cases.CP involvement in OSAS screening is a cost-effective strategy. This proposal is consistent with the trend in Europe and the United States to extend the practices and responsibilities of the pharmacist in primary care.

  2. A comparison of scoring models for computerised mental health screening for federal prison inmates.

    Science.gov (United States)

    Martin, Michael S; Wamboldt, Ashley D; O'Connor, Shannon L; Fortier, Julie; Simpson, Alexander I F

    2013-02-01

    There are high rates of mental disorder in correctional environments, so effective mental health screening is needed. Implementation of the computerised mental health screen of the Correctional Service of Canada has led to improved identification of offenders with mental health needs but with high rates of false positives. The goal of this study is to evaluate the use of an iterative classification tree (ICT) approach to mental health screening compared with a simple binary approach using cut-off scores on screening tools. A total of 504 consecutive admissions to federal prison completed the screen and were also interviewed by a mental health professional. Relationships between screening results and more extended assessment and clinical team discussion were tested. The ICT was more parsimonious in identifying probable 'cases' than standard binary screening. ICT was also highly accurate at detecting mental health needs (AUC=0.87, 95% CI 0.84-0.90). The model identified 118 (23.4%) offenders as likely to need further assessment or treatment, 87% of whom were confirmed cases at clinical interview. Of the 244 (48.4%) offenders who were screened out, only 9% were clinically assessed as requiring further assessment or treatment. Standard binary screening was characterised by more false positives and a comparable false negative rate. The use of ICTs to interpret screening data on the mental health of prisoners needs further evaluation in independent samples in Canada and elsewhere. This first evaluation of the application of such an approach offers the prospect of more effective and efficient use of the scarce resource of mental health services in prisons. Although not required, the use of computers can increase the ease of implementing an ICT model. Copyright © 2013 John Wiley & Sons, Ltd.

  3. Quality assurance target for community-based breast cancer screening in China: a model simulation.

    Science.gov (United States)

    Yang, Lan; Wang, Jing; Cheng, Juan; Wang, Yuan; Lu, Wenli

    2018-03-07

    We aimed to clarify the feasibility of a community-based screening strategy for breast cancer in Tianjin, China; to identify the factors that most significantly influenced its feasibility; and to identify the reference range for quality control. A state-transition Markov model simulated a hypothetical cohort of 100,000 healthy women, the start aged was set at 35 years and the time horizon was set to 50 years. The primary outcome for the model was the incremental cost-utility ratio (ICUR), defined as the program's cost per quality-adjusted life year (QALY) gained. Three screening strategies providing by community health service for women aged 35 to 69 years was compared regarding to different intervals. The probability of the ICUR being below 20 272USD (i.e., triple the annual gross domestic product [3 GDPs]) per QALY saved was 100% for annual screening strategy and screening every three years. Only when the attendance rate was > 50%, the probability for annual screening would be cost effective > 95%. The probability for the annual screening strategy being cost effective could reach to 95% for a willingness-to-pay (WTP) of 2 GDPs when the compliance rate for transfer was > 80%. When 10% stage I tumors were detected by screening, the probability of the annual screening strategy being cost effective would be up to 95% for a WTP > 3 GDPs. Annual community-based breast cancer screening was cost effective for a WTP of 3 GDP based on the incidence of breast cancer in Tianjin, China. Measures are needed to ensure performance indicators to a desirable level for the cost-effectiveness of breast cancer screening.

  4. Modeling of the maintenance policy of an offshore wind farm

    International Nuclear Information System (INIS)

    Maddens, L.; Labeau, P.E.

    2004-01-01

    Wind energy has a key position in the market of renewable electricity production means. Offshore wind farms offer additional surfaces to exploit this form of energy, together with more favourable wind conditions. Yet offshore windmills ask for higher investment and maintenance costs. Optimising the latter costs should therefore turn out to be particularly beneficial for this technology. The present paper summarizes the main modelling aspects of the maintenance of a typical offshore wind farm, such as the accessibility of the wind turbines and the impact of weather conditions, the cost of the different transport resources, the number of maintenance teams, a tolerated unavailability of part of the windmills, the opportunity to combine corrective and preventive maintenance actions on one or several windmills. All these features were embedded in a Petri net model of the maintenance policy of the farm, allowing to estimate the maintenance costs entailed by several strategies. Advantages and drawbacks of using Petri nets for the modelling of such a maintenance strategy are finally discussed. (authors)

  5. Creation of a National, At-home Model for Ashkenazi Jewish Carrier Screening.

    Science.gov (United States)

    Grinzaid, Karen Arnovitz; Page, Patricia Zartman; Denton, Jessica Johnson; Ginsberg, Jessica

    2015-06-01

    Ethnicity-based carrier screening for the Ashkenazi Jewish population has been available and encouraged by advocacy and community groups since the early 1970's. Both the American College of Medical Genetics and the American Congress of Obstetricians and Gynecologists recommend carrier screening for this population (Obstetrics and Gynecology, 114(4), 950-953, 2009; Genetics in Medicine, 10(1), 55-56, 2008). While many physicians inquire about ethnic background and offer appropriate carrier screening, studies show that a gap remains in implementing recommendations (Genetic testing and molecular biomarkers, 2011). In addition, education and outreach efforts targeting Jewish communities have had limited success in reaching this at-risk population. Despite efforts by the medical and Jewish communities, many Jews of reproductive age are not aware of screening, and remain at risk for having children with preventable diseases. Reaching this population, preferably pre-conception, and facilitating access to screening is critically important. To address this need, genetic counselors at Emory University developed JScreen, a national Jewish genetic disease screening program. The program includes a national marketing and PR campaign, online education, at-home saliva-based screening, post-test genetic counseling via telephone or secure video conferencing, and referrals for face-to-face genetic counseling as needed. Our goals are to create a successful education and screening program for this population and to develop a model that could potentially be used for other at-risk populations.

  6. Modeling sustainable groundwater management: packaging and sequencing of policy interventions.

    Science.gov (United States)

    Esteban, Encarna; Dinar, Ariel

    2013-04-15

    Of the many studies estimating effectiveness of policy reforms most have been considering various types of policy reforms in isolation from each other. Such pattern has also been the case in water resource regulations. In the case of groundwater almost all policy interventions considered in the literature have been implemented individually, without taking into account the possible interactions and impacts among them. In this paper, we focus on two policy instruments: water quota and uniform water tax. The paper demonstrates how packaging and sequencing sets of policy interventions, with possible triggers to initiate their time of implementation, may be more effective in achieving a sustainable groundwater management than single policies when environmental externalities exist. The policy instruments are applied to the Western la Mancha aquifer in Southeast Spain, a major aquifer that is managed by a command and control approach. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Agri‐environmental Policies to Meet Consumer Preferences in Japan: An Economic‐Biophysical Model Approach

    Directory of Open Access Journals (Sweden)

    Tetsuya Uetake

    2014-08-01

    Full Text Available Promoting environmentally friendly farming products is crucial to meeting consumer demand. Although governments implement policy measures to improve the environmental performance of the agriculture sector, theirimpacts are difficult to assess. This study analyses the performance of agri‐environmental policies in Japan, by using the OECD’s policy impact model and reference level framework. In particular, it identifies the environmental impacts of three simulated agri‐environmental policies based on farms’ characteristics. The results suggest that a policy mix of regulation and an incentive payment would reduce environmental impacts, suggesting that targeted approaches could improve the cost‐effectiveness of agri‐environmental policies.

  8. Circuit models for Salisbury screens made from unidirectional carbon fiber composite sandwich structures

    Science.gov (United States)

    Riley, Elliot J.; Lenzing, Erik H.; Narayanan, Ram M.

    2016-05-01

    Carbon fiber composite materials have many useful structural material properties. The electromagnetic perfor- mance of these materials is of great interest for future applications. The work presented in this paper deals with the construction of Salisbury screen microwave absorbers made from unidirectional carbon fiber composite sand- wich structures. Specifically, absorbers centered at 7.25 GHz and 12.56 GHz are investigated. Circuit models are created to match the measured performance of the carbon fiber Salisbury screens using a genetic algorithm to extract lumped element circuit values. The screens presented in this paper utilize unidirectional carbon fiber sheets in place of the resistive sheet utilized in the classic Salisbury screen. The theory, models, prototypes, and measurements of these absorbers are discussed.

  9. The Timber Resource Inventory Model (TRIM): a projection model for timber supply and policy analysis.

    Science.gov (United States)

    P.L. Tedder; R.N. La Mont; J.C. Kincaid

    1987-01-01

    TRIM (Timber Resource Inventory Model) is a yield table projection system developed for timber supply projections and policy analysis. TRIM simulates timber growth, inventories, management and area changes, and removals over the projection period. Programs in the TRIM system, card-by-card descriptions of required inputs, table formats, and sample results are presented...

  10. Optimal Operational Monetary Policy Rules in an Endogenous Growth Model: a calibrated analysis

    OpenAIRE

    Arato, Hiroki

    2009-01-01

    This paper constructs an endogenous growth New Keynesian model and considers growth and welfare effect of Taylor-type (operational) monetary policy rules. The Ramsey equilibrium and optimal operational monetary policy rule is also computed. In the calibrated model, the Ramseyoptimal volatility of inflation rate is smaller than that in standard exogenous growth New Keynesian model with physical capital accumulation. Optimal operational monetary policy rule makes nominal interest rate respond s...

  11. A Model-Based Exploration and Policy Analysis Related to Prostitution and Human Trafficking

    OpenAIRE

    András Kővári; Erik Pruyt

    2014-01-01

    This paper presents a model-based exploration and policy analysis related to prostitution and prostitution-related human trafficking. After a brief introduction to prostitution and prostitution-related human trafficking, the paper zooms in on the Dutch situation. A System Dynamics simulation model related to the Dutch situation developed to explore and provide policy insights is subsequently presented. Using the simulation model, policies are first of all tested, and preliminary conclusions a...

  12. A Model for Assessing the Gender Aspect in Economic Policy

    Directory of Open Access Journals (Sweden)

    Ona Rakauskienė

    2015-06-01

    Full Text Available The purpose of research is to develop a conceptual model for assessing the impact of the gender aspect on economic policy at macro– and microeconomic levels. The research methodology is based on analysing scientific approaches to the gender aspect in economics and gender–responsive budgeting as well as determining the impact of the gender aspect on GDP, foreign trade, the state budget and the labour market. First, the major findings encompass the main idea of a conceptual model proposing that a socio–economic picture of society can be accepted as completed only when, alongside public and private sectors, includes the care/reproductive sector that is dominated by women and creating added value in the form of educated human resources; second, macroeconomics is not neutral in terms of gender equality. Gender asymmetry is manifested not only at the level of microeconomics (labour market and business but also at the level of macroeconomics (GDP, the state budget and foreign trade, which has a negative impact on economic growth and state budget revenues. In this regard, economic decisions, according to the principles of gender equality and in order to achieve gender equality in economics, must be made, as the gender aspect has to be also implemented at the macroeconomic level.

  13. A policy model to initiate environmental negotiations: Three hydropower workshops

    Science.gov (United States)

    Lamb, Berton Lee; Taylor, Jonathan G.; Burkardt, Nina; Ponds, Phadrea D.

    1998-01-01

    How do I get started in natural resource negotiations? Natural resource managers often face difficult negotiations when they implement laws and policies regulating such resources as water, wildlife, wetlands, endangered species, and recreation. As a result of these negotiations, managers must establish rules, grant permits, or create management plans. The Legal‐Institutional Analysis Model (LIAM) was designed to assist managers in systematically analyzing the parties in natural resource negotiations and using that analysis to prepare for bargaining. The LIAM relies on the theory that organizations consistently employ behavioral roles. The model uses those roles to predict likely negotiation behavior. One practical use of the LIAM is when all parties to a negotiation conduct a workshop as a way to open the bargaining on a note of trust and mutual understanding. The process and results of three LIAM workshops designed to guide hydroelectric power licensing negotiations are presented. Our experience with these workshops led us to conclude that the LIAM can be an effective tool to begin a negotiation and that trust built through the workshops can help create a successful result.

  14. Integrating agricultural research and policy analysis: analytical framework and policy applications for bio-economic modelling.

    NARCIS (Netherlands)

    Ruben, R.; Moll, H.; Kuyvenhoven, A.

    1998-01-01

    Interdisciplinary approaches to identify suitable incentives for enhancing sustainable natural resource use require an analytical framework that satisfies both practical purposes of policy support and disciplinary requirements regarding the specification of underlying technical and behavioural

  15. Optimization of Simple Monetary Policy Rules on the Base of Estimated DSGE-model

    OpenAIRE

    Shulgin, A.

    2015-01-01

    Optimization of coefficients in monetary policy rules is performed on the base of the DSGE-model with two independent monetary policy instruments estimated on the Russian data. It was found that welfare maximizing policy rules lead to inadequate result and pro-cyclical monetary policy. Optimal coefficients in Taylor rule and exchange rate rule allow to decrease volatility estimated on Russian data of 2001-2012 by about 20%. The degree of exchange rate flexibility parameter was found to be low...

  16. General and Partial Equilibrium Modeling of Sectoral Policies to Address Climate Change in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Pizer, William; Burtraw, Dallas; Harrington, Winston; Newell, Richard; Sanchirico, James; Toman, Michael

    2003-03-31

    This document provides technical documentation for work using detailed sectoral models to calibrate a general equilibrium analysis of market and non-market sectoral policies to address climate change. Results of this work can be found in the companion paper, "Modeling Costs of Economy-wide versus Sectoral Climate Policies Using Combined Aggregate-Sectoral Model".

  17. Dissolving decision making? : Models and their roles in decision-making processes and policy at large

    NARCIS (Netherlands)

    Zeiss, Ragna; van Egmond, S.

    2014-01-01

    This article studies the roles three science-based models play in Dutch policy and decision making processes. Key is the interaction between model construction and environment. Their political and scientific environments form contexts that shape the roles of models in policy decision making.

  18. Political economy models and agricultural policy formation : empirical applicability and relevance for the CAP

    NARCIS (Netherlands)

    Zee, van der F.A.

    1997-01-01

    This study explores the relevance and applicability of political economy models for the explanation of agricultural policies. Part I (chapters 4-7) takes a general perspective and evaluates the empirical applicability of voting models and interest group models to agricultural policy

  19. Modeling Accessibility of Screening and Treatment Facilities for Older Adults using Transportation Networks.

    Science.gov (United States)

    Zhang, Qiuyi; Northridge, Mary E; Jin, Zhu; Metcalf, Sara S

    2018-04-01

    Increased lifespans and population growth have resulted in an older U.S. society that must reckon with the complex oral health needs that arise as adults age. Understanding accessibility to screening and treatment facilities for older adults is necessary in order to provide them with preventive and restorative services. This study uses an agent-based model to examine the accessibility of screening and treatment facilities via transportation networks for older adults living in the neighborhoods of northern Manhattan, New York City. Older adults are simulated as socioeconomically distinct agents who move along a GIS-based transportation network using transportation modes that mediate their access to screening and treatment facilities. This simulation model includes four types of mobile agents as a simplifying assumption: walk, by car, by bus, or by van (i.e., a form of transportation assistance for older adults). These mobile agents follow particular routes: older adults who travel by car, bus, and van follow street roads, whereas pedestrians follow walkways. The model enables the user to focus on one neighborhood at a time for analysis. The spatial dimension of an older adult's accessibility to screening and treatment facilities is simulated through the travel costs (indicated by travel time or distance) incurred in the GIS-based model environment, where lower travel costs to screening and treatment facilities imply better access. This model provides a framework for representing health-seeking behavior that is contextualized by a transportation network in a GIS environment.

  20. Health care models guiding mental health policy in Kenya 1965 - 1997

    Directory of Open Access Journals (Sweden)

    Jenkins Rachel

    2010-04-01

    Full Text Available Abstract Background Mental health policy is needed to set the strategy and direction for the provision of mental health services in a country. Policy formulation does not occur in a vacuum, however, but is influenced by local and international factors in the health sector and other sectors. Methods This study was carried out in 1997 to examine the evolution of mental health policy in Kenya between 1965 and 1997 in the context of changing international concepts of health and development. Qualitative content analysis of policy documents was combined with interviews of key policy makers. Results The study showed that during the period 1965-1997 the generic health policy in Kenya changed from one based on the Medical Model in the 1960s and 1970s to one based on the Primary Health Care Model in the late 1970s and the 1980s and finally to one based on the Market Model of health care in the 1990s. The mental health policy, on the other hand, evolved from one based on the Medical Model in the 1960s to one based on the Primary Health Care Model in the 1990s, but did not embrace the Market Model of health care. This resulted in a situation in the 1990s where the mental health policy was rooted in a different conceptual model from that of the generic health policy under which it was supposed to be implemented. This "Model Muddlement" may have impeded the implementation of the mental health policy in Kenya. Conclusions Integration of the national mental health policy with the general health policy and other sector policies would be appropriate and is now underway.

  1. Modeling fiber motion in a pulp pressure screen: the effect of slot shape

    International Nuclear Information System (INIS)

    Dong, S.; Salcudean, M.; Gartshore, I.

    2003-01-01

    A pressure screen is a piece of equipment in the pulp and paper industry used either to remove contaminants from the pulp suspension or to separate fibers having different properties. Contaminants such as fiber bundles, bark and plastic specks are introduced when fibers are separated from the wood by mechanical or chemical pulping processes. Contaminants significantly affect the strength and smoothness of the paper and must be removed before the final paper is produced. The screen plate is a critical part of the pressure screen and its design is the key to screen performance. This paper uses a new and comprehensive CFD simulation tool to examine the flow and fiber behavior in a single slot screen having any reasonable slot shape. -This simulation tool includes three coupled models: first, the flow model solves the Reynolds Averaged Navier-Stokes (RANS) equation using the standard k - ε turbulence model to predict the flow field in the equipment. Second, a three-dimensional flexible fiber model is used to track the fiber trajectory in the screen. Third, a very general wall model is used to deal with the case when a fiber touches the equipment wall. The simulated results show that the slot shape has a critical influence on fiber behavior and screen performance. Three general slot shapes were investigated: the smooth slot, the step-step contour slot and slope-slope contour slot. Of these the slope-slope contour slot provides the best passage for the fibers with a length of 1mm and 3mm. (author)

  2. The sociocultural health behavioral model and disparities in colorectal cancer screening among Chinese Americans

    Science.gov (United States)

    Ma, Grace X; Wang, Min Qi; Ma, Xiang S; Kim, Giyeon; Toubbeh, Jamil; Shive, Steven

    2013-01-01

    Objective The purpose of this study was to validate a Sociocultural Health Behavior Model using a structural equation analysis to determine the direction and magnitude of the interdependence of model components in relation to health behavior associated with colorectal cancer (CRC) screening among Chinese Americans. Methods A cross-sectional design included a sample of 311 Chinese American men and women age 50 and older. The initial step involved use of confirmatory factor analysis which included the following variables: access/satisfaction with health care, enabling, predisposing, cultural, and health belief factors. Structural equation modeling analyses were conducted on factors for CRC screening. Results Education and health insurance status were significantly related to CRC screening. Those with less than a high school education and without health insurance were more likely to be “never screened” for CRC than those having more education and health insurance. The path analysis findings also lend support for components of the Sociocultural Health Belief Model and indicated that there was a positive and significant relationship between CRC screening and the enabling factors, between cultural factors and predisposing, enabling, and access/satisfaction with health care factors and between enabling factors and access/satisfaction with health care. Conclusions The model highlights the significance that sociocultural factors play in relation to CRC screening and reinforced the need to assist Chinese with poor English proficiency in translation and awareness of the importance of CRC screening. The use of community organizations may play a role in assisting Chinese to enhance colorectal cancer screening rates. PMID:25364475

  3. 'Inside-out', back-to-front: a model for clinical population genetic screening.

    Science.gov (United States)

    Shickle, D; Harvey, I

    1993-07-01

    Developments in DNA technology have resulted in a dramatic increase in the number of genes identified. With the localisation of a gene it is possible to devise procedures suitable for mass carrier screening programmes. Until recently mass carrier screening was only possible for a limited number of disorders, for example, Tay-Sachs disease and haemoglobinopathies. Counselling possible carriers was based on estimations of risk. The momentum towards mass carrier screening is likely to be increased by gene therapy. Carrier screening for cystic fibrosis alone will have dramatic implications for genetic service provision as 4 to 5% of the UK population carry the CF gene. The potential for genetic screening of multifactorial diseases, for example, cancers, should also be considered. The existing organisation of genetic services is likely to be inadequate. A new specialty of clinical population genetics is required. A model is proposed of clinical population genetic screening programmes, organised under a 'common umbrella' led by a public health physician, while screening and follow up will remain the responsibility of the appropriate clinician.

  4. How can land-use modelling tools inform bioenergy policies?

    Science.gov (United States)

    Davis, Sarah C.; House, Joanna I.; Diaz-Chavez, Rocio A.; Molnar, Andras; Valin, Hugo; DeLucia, Evan H.

    2011-01-01

    Targets for bioenergy have been set worldwide to mitigate climate change. Although feedstock sources are often ambiguous, pledges in European nations, the United States and Brazil amount to more than 100 Mtoe of biorenewable fuel production by 2020. As a consequence, the biofuel sector is developing rapidly, and it is increasingly important to distinguish bioenergy options that can address energy security and greenhouse gas mitigation from those that cannot. This paper evaluates how bioenergy production affects land-use change (LUC), and to what extent land-use modelling can inform sound decision-making. We identified local and global internalities and externalities of biofuel development scenarios, reviewed relevant data sources and modelling approaches, identified sources of controversy about indirect LUC (iLUC) and then suggested a framework for comprehensive assessments of bioenergy. Ultimately, plant biomass must be managed to produce energy in a way that is consistent with the management of food, feed, fibre, timber and environmental services. Bioenergy production provides opportunities for improved energy security, climate mitigation and rural development, but the environmental and social consequences depend on feedstock choices and geographical location. The most desirable solutions for bioenergy production will include policies that incentivize regionally integrated management of diverse resources with low inputs, high yields, co-products, multiple benefits and minimal risks of iLUC. Many integrated assessment models include energy resources, trade, technological development and regional environmental conditions, but do not account for biodiversity and lack detailed data on the location of degraded and underproductive lands that would be ideal for bioenergy production. Specific practices that would maximize the benefits of bioenergy production regionally need to be identified before a global analysis of bioenergy-related LUC can be accomplished. PMID

  5. Analytical model for screening potential CO2 repositories

    Science.gov (United States)

    Okwen, R.T.; Stewart, M.T.; Cunningham, J.A.

    2011-01-01

    Assessing potential repositories for geologic sequestration of carbon dioxide using numerical models can be complicated, costly, and time-consuming, especially when faced with the challenge of selecting a repository from a multitude of potential repositories. This paper presents a set of simple analytical equations (model), based on the work of previous researchers, that could be used to evaluate the suitability of candidate repositories for subsurface sequestration of carbon dioxide. We considered the injection of carbon dioxide at a constant rate into a confined saline aquifer via a fully perforated vertical injection well. The validity of the analytical model was assessed via comparison with the TOUGH2 numerical model. The metrics used in comparing the two models include (1) spatial variations in formation pressure and (2) vertically integrated brine saturation profile. The analytical model and TOUGH2 show excellent agreement in their results when similar input conditions and assumptions are applied in both. The analytical model neglects capillary pressure and the pressure dependence of fluid properties. However, simulations in TOUGH2 indicate that little error is introduced by these simplifications. Sensitivity studies indicate that the agreement between the analytical model and TOUGH2 depends strongly on (1) the residual brine saturation, (2) the difference in density between carbon dioxide and resident brine (buoyancy), and (3) the relationship between relative permeability and brine saturation. The results achieved suggest that the analytical model is valid when the relationship between relative permeability and brine saturation is linear or quasi-linear and when the irreducible saturation of brine is zero or very small. ?? 2011 Springer Science+Business Media B.V.

  6. THE HYDROCARBON SPILL SCREENING MODEL (HSSM), VOLUME 2: THEORETICAL BACKGROUND AND SOURCE CODES

    Science.gov (United States)

    A screening model for subsurface release of a nonaqueous phase liquid which is less dense than water (LNAPL) is presented. The model conceptualizes the release as consisting of 1) vertical transport from near the surface to the capillary fringe, 2) radial spreading of an LNAPL l...

  7. Analysis, Modeling, and Simulation (AMS) testbed initial screening report.

    Science.gov (United States)

    2013-11-01

    Analysis Modeling and Simulation (AMS) Testbeds can make significant contributions in identifying the benefits of more effective, more active systems management, resulting from integrating transformative applications enabled by new data from wireless...

  8. Dynamic Systems Modeling in Educational System Design & Policy

    Science.gov (United States)

    Groff, Jennifer Sterling

    2013-01-01

    Over the last several hundred years, local and national educational systems have evolved from relatively simple systems to incredibly complex, interdependent, policy-laden structures, to which many question their value, effectiveness, and direction they are headed. System Dynamics is a field of analysis used to guide policy and system design in…

  9. Agile: a problem-based model of regulatory policy making

    NARCIS (Netherlands)

    Boer, A.; van Engers, T.

    2013-01-01

    We understand regulatory policy problems against the backdrop of existing implementations of a regulatory framework. There are argument schemes for proposing a policy and for criticising a proposal, rooted in a shared understanding that there is an existing regulatory framework which is implemented

  10. METHOD FOR NUMERICAL MODELING OF UNSTEADY SEPARATED FLOW AROUND AIRFOILS MOVING CLOSE TO FLAT SCREEN

    Directory of Open Access Journals (Sweden)

    V. Pogrebnaya Tamara

    2017-01-01

    Full Text Available In this article an attempt is made to explain the nature of differences in measurements of forces and moments, which influence an aircraft at take-off and landing when testing on different types of stands. An algorithm for numerical simulation of unsteady separated flow around airfoil is given. The algorithm is based on the combination of discrete vortex method and turbulent boundary layer equations. An unsteady flow separation modeling has been used. At each interval vortex method was used to calculate the potential flow around airfoils located near a screen. Calculated pressures and velocities were then used in boundary layer calculations to determine flow separation points and separated vortex in- tensities. After that calculation were made to determine free vortex positions to next time step and the process was fulfilled for next time step. The proposed algorithm allows using numeric visualization to understand physical picture of flow around airfoil moving close to screen. Three different ways of flow modeling (mirror method, fixed or movable screens were tested. In each case the flow separation process, which determines pressure distribution over airfoil surface and influ- ences aerodynamic performance, was viewed. The results of the calculations showed that at low atitudes of airfoil over screen mirror method over predicts lift force compared with movable screen, while fixed screen under predicts it. The data obtained can be used when designing equipment for testing in wind tunnels.

  11. Por La Vida model intervention enhances use of cancer screening tests among Latinas.

    Science.gov (United States)

    Navarro, A M; Senn, K L; McNicholas, L J; Kaplan, R M; Roppé, B; Campo, M C

    1998-07-01

    To describe the short-term impact of the intervention known as Por La Vida (PLV) on cancer screening for Latinas in San Diego, California. Thirty-six lay community workers (consejeras) were recruited and trained to conduct educational group sessions. Each consejera recruited approximately 14 peers from the community to participate in the program. The consejeras were randomly assigned to either a twelve-week cancer screening intervention group or a control group in which they participated in an equally engaging program entitled "Community Living Skills." Pre- and post-intervention self-report information was obtained from project participants on the use of cancer screening examinations. Outcome measures were changes in the percentages of women who had breast and cervical cancer screening test within the past year before and after the intervention occurred. Experimental and control groups were compared using t-tests. Analyses were conducted using both consejeras and participants as the unit of analysis. The increase in the use of the cancer screening test was higher in the PLV cancer intervention group in comparison to women in the community living skills control group. Key to the PLV intervention model is the identification of natural helpers in the Latino community and their subsequent training in intervention based on social learning theory using culturally appropriate educational materials. The model is an effective and viable approach for increasing the use of cancer screening tests in Latinas of low socioeconomic level and low level of acculturation.

  12. Lead-Time Models Should Not Be Used to Estimate Overdiagnosis in Cancer Screening

    DEFF Research Database (Denmark)

    Zahl, Per-Henrik; Jørgensen, Karsten Juhl; Gøtzsche, Peter C

    2014-01-01

    . It is the average time at which the diagnosis is brought forward for both clinically relevant and overdiagnosed cancers. When screening for breast cancer, clinical lead-time is about 1 year, while model-based lead-time varies from 2 to 7 years. There are two different methods to calculate overdiagnosis in cancer...... screening--the excess-incidence approach and the lead-time approach--that rely on two different lead-time definitions. Overdiagnosis when screening with mammography has varied from 0 to 75 %. We have explained that these differences are mainly caused by using different definitions and methods...... and not by variations in data. High levels of overdiagnosis of cancer have usually been explained by detection of many slow-growing tumors with long lead-times. This theory can be tested by studying if slow-growing tumors accumulate in the absence of screening, which they don't. Thus, it is likely that the natural...

  13. OPTIMAL TRAINING POLICY FOR PROMOTION - STOCHASTIC MODELS OF MANPOWER SYSTEMS

    Directory of Open Access Journals (Sweden)

    V.S.S. Yadavalli

    2012-01-01

    Full Text Available In this paper, the optimal planning of manpower training programmes in a manpower system with two grades is discussed. The planning of manpower training within a given organization involves a trade-off between training costs and expected return. These planning problems are examined through models that reflect the random nature of manpower movement in two grades. To be specific, the system consists of two grades, grade 1 and grade 2. Any number of persons in grade 2 can be sent for training and after the completion of training, they will stay in grade 2 and will be given promotion as and when vacancies arise in grade 1. Vacancies arise in grade 1 only by wastage. A person in grade 1 can leave the system with probability p. Vacancies are filled with persons in grade 2 who have completed the training. It is assumed that there is a perfect passing rate and that the sizes of both grades are fixed. Assuming that the planning horizon is finite and is T, the underlying stochastic process is identified as a finite state Markov chain and using dynamic programming, a policy is evolved to determine how many persons should be sent for training at any time k so as to minimize the total expected cost for the entire planning period T.

  14. Screening model for assessing doses from radiological accidents

    International Nuclear Information System (INIS)

    Sjoreen, A.L.; Athey, G.F.; Sakenas, C.A.; McKenna, T.J.

    1988-01-01

    A new dose assessment model, called RASCAL, has been written for the US Nuclear Regulatory Commission (NRC) for use during response to emergencies. RASCAL is designed to provide rough estimates of the health effects from a radiological accident in progress and only limited information is available. RASCAL will be used by the NRC personnel who report to the site of a nuclear accident to conduct an independent evaluation of dose projections. It was written to correct the technical and operational problems in NRC's previous model and to be more appropriate to the personal computers presently in use by the NRC. The model has been constructed to be easy to modify, with separate modules for estimation of the quantity of radioactivity released, its transport through the atmosphere, and the resulting radiologic dose to man. RASCAL results can be displayed in graphical or ASCII form. 4 refs

  15. Maternal Serologic Screening to Prevent Congenital Toxoplasmosis: A Decision-Analytic Economic Model

    Science.gov (United States)

    Stillwaggon, Eileen; Carrier, Christopher S.; Sautter, Mari; McLeod, Rima

    2011-01-01

    Objective To determine a cost-minimizing option for congenital toxoplasmosis in the United States. Methodology/Principal Findings A decision-analytic and cost-minimization model was constructed to compare monthly maternal serological screening, prenatal treatment, and post-natal follow-up and treatment according to the current French (Paris) protocol, versus no systematic screening or perinatal treatment. Costs are based on published estimates of lifetime societal costs of developmental disabilities and current diagnostic and treatment costs. Probabilities are based on published results and clinical practice in the United States and France. One- and two-way sensitivity analyses are used to evaluate robustness of results. Universal monthly maternal screening for congenital toxoplasmosis with follow-up and treatment, following the French protocol, is found to be cost-saving, with savings of $620 per child screened. Results are robust to changes in test costs, value of statistical life, seroprevalence in women of childbearing age, fetal loss due to amniocentesis, and to bivariate analysis of test costs and incidence of primary T. gondii infection in pregnancy. Given the parameters in this model and a maternal screening test cost of $12, screening is cost-saving for rates of congenital infection above 1 per 10,000 live births. If universal testing generates economies of scale in diagnostic tools—lowering test costs to about $2 per test—universal screening is cost-saving at rates of congenital infection well below the lowest reported rates in the United States of 1 per 10,000 live births. Conclusion/Significance Universal screening according to the French protocol is cost saving for the US population within broad parameters for costs and probabilities. PMID:21980546

  16. Maternal serologic screening to prevent congenital toxoplasmosis: a decision-analytic economic model.

    Directory of Open Access Journals (Sweden)

    Eileen Stillwaggon

    2011-09-01

    Full Text Available To determine a cost-minimizing option for congenital toxoplasmosis in the United States.A decision-analytic and cost-minimization model was constructed to compare monthly maternal serological screening, prenatal treatment, and post-natal follow-up and treatment according to the current French (Paris protocol, versus no systematic screening or perinatal treatment. Costs are based on published estimates of lifetime societal costs of developmental disabilities and current diagnostic and treatment costs. Probabilities are based on published results and clinical practice in the United States and France. One- and two-way sensitivity analyses are used to evaluate robustness of results. Universal monthly maternal screening for congenital toxoplasmosis with follow-up and treatment, following the French protocol, is found to be cost-saving, with savings of $620 per child screened. Results are robust to changes in test costs, value of statistical life, seroprevalence in women of childbearing age, fetal loss due to amniocentesis, and to bivariate analysis of test costs and incidence of primary T. gondii infection in pregnancy. Given the parameters in this model and a maternal screening test cost of $12, screening is cost-saving for rates of congenital infection above 1 per 10,000 live births. If universal testing generates economies of scale in diagnostic tools-lowering test costs to about $2 per test-universal screening is cost-saving at rates of congenital infection well below the lowest reported rates in the United States of 1 per 10,000 live births.Universal screening according to the French protocol is cost saving for the US population within broad parameters for costs and probabilities.

  17. Foam Assisted WAG, Snorre Revisit with New Foam Screening Model

    DEFF Research Database (Denmark)

    Spirov, Pavel; Rudyk, Svetlana Nikolayevna; Khan, Arif

    2012-01-01

    This study deals with simulation model of Foam Assisted Water Alternating Gas (FAWAG) method that had been implemented to two Norwegian Reservoirs. Being studied on number of pilot projects, the method proved successful, but Field Scale simulation was never understood properly. New phenomenologic...

  18. Erythrocytes as a biological model for screening of xenobiotics toxicity.

    Science.gov (United States)

    Farag, Mayada Ragab; Alagawany, Mahmoud

    2018-01-05

    Erythrocytes are the main cells in circulation. They are devoid of internal membrane structures and easy to be isolated and handled providing a good model for different assays. Red blood cells (RBCs) plasma membrane is a multi-component structure that keeps the cell morphology, elasticity, flexibility and deformability. Alteration of membrane structure upon exposure to xenobiotics could induce various cellular abnormalities and releasing of intracellular components. Therefore the morphological changes and extracellular release of haemoglobin [hemolysis] and increased content of extracellular adenosine triphosphate (ATP) [as signs of membrane stability] could be used to evaluate the cytotoxic effects of various molecules. The nucleated RBCs from birds, fish and amphibians can be used to evaluate genotoxicity of different xenobiotics using comet, DNA fragmentation and micronucleus assays. The RBCs could undergo programmed cell death (eryptosis) in response to injury providing a useful model to analyze some mechanisms of toxicity that could be implicated in apoptosis of nucleated cells. Erythrocytes are vulnerable to peroxidation making it a good biological membrane model for analyzing the oxidative stress and lipid peroxidation of various xenobiotics. The RBCs contain a large number of enzymatic and non-enzymatic antioxidants. The changes of the RBCs antioxidant capacity could reflect the capability of xenobiotics to generate reactive oxygen species (ROS) resulting in oxidative damage of tissue. These criteria make RBCs a valuable in vitro model to evaluate the cytotoxicity of different natural or synthetic and organic or inorganic molecules by cellular damage measures. Copyright © 2017. Published by Elsevier B.V.

  19. Simple Screened Hydrogen Model of Excitons in Two-Dimensional Materials

    DEFF Research Database (Denmark)

    Olsen, Thomas; Latini, Simone; Rasmussen, Filip Anselm

    2016-01-01

    We present a generalized hydrogen model for the binding energies (EB) and radii of excitons in two-dimensional (2D) materials that sheds light on the fundamental differences between excitons in two and three dimensions. In contrast to the well-known hydrogen model of three-dimensional (3D) excitons......, the description of 2D excitons is complicated by the fact that the screening cannot be assumed to be local. We show that one can consistently define an effective 2D dielectric constant by averaging the screening over the extend of the exciton. For an ideal 2D semiconductor this leads to a simple expression for EB...

  20. Simulation modeling of policies directed at youth sugar-sweetened beverage consumption.

    Science.gov (United States)

    Levy, David T; Friend, Karen B

    2013-03-01

    Childhood obesity is a significant public health problem requiring innovative solutions. While recent reviews indicate that some policies show promise, there is a lack of information regarding which policies, and policy combinations, work best. Low-nutrition, energy-dense foods and beverages such as sugar-sweetened beverages (SSBs) have been identified as a major contributor to the problem. The purpose of this paper is to use simulation modeling to show how changes in three categories of SSB policies-school nutrition, school-based education, and taxes-impact SSB and other food consumption. The model shows that policies directed at SSBs, particularly tax hikes, could lead to substantial reductions in the number of calories consumed by youth. The estimates, however, are subject to a high degree of uncertainty. Estimates from school-based nutrition and school-based education policies, while also helping to reduce caloric intake, generally show smaller effects than tax policies and considerable variation around parameter estimates for individual and combined policies. We conclude with a discussion of the limits of the model, and suggest where additional information is needed. Limitations notwithstanding, simulation modeling is a promising methodology that can help advance our understanding of policy effects, thereby helping policymakers to better formulate effective policies to reduce obesity prevalence and the associated social harms.

  1. The Dynamics of an HIV/AIDS Model with Screened Disease Carriers

    Directory of Open Access Journals (Sweden)

    S. D. Hove-Musekwa

    2009-01-01

    Full Text Available The presence of carriers usually complicates the dynamics and prevention of a disease. They are not recognized as disease cases themselves unless they are screened and they usually spread the infection without them being aware. We argue that this has been one of the major causes of the spread of human immunodeficiency virus (HIV. We propose, in this paper, a model for the heterogeneous transmission of HIV/acquired immunodeficiency syndrome in the presence of disease carriers. The model allows us to assess the role of screening, as an intervention program that can slow the epidemic. A threshold value ψ*, for the screening rate is obtained. It is shown numerically that if 80% or more of the carrier population is screened, the epidemic can be contained. The qualitative analysis is done in terms of the model reproduction number R. The model has two equilibria, the disease free equilibrium and a unique endemic equilibrium. The disease free equilibrium is globally stable of R  1. A detailed discussion of the model reproduction number is given and numerical simulations are done to show the role of some of the important model parameters.

  2. Estimation of the applicability domain of kernel-based machine learning models for virtual screening

    Directory of Open Access Journals (Sweden)

    Fechner Nikolas

    2010-03-01

    Full Text Available Abstract Background The virtual screening of large compound databases is an important application of structural-activity relationship models. Due to the high structural diversity of these data sets, it is impossible for machine learning based QSAR models, which rely on a specific training set, to give reliable results for all compounds. Thus, it is important to consider the subset of the chemical space in which the model is applicable. The approaches to this problem that have been published so far mostly use vectorial descriptor representations to define this domain of applicability of the model. Unfortunately, these cannot be extended easily to structured kernel-based machine learning models. For this reason, we propose three approaches to estimate the domain of applicability of a kernel-based QSAR model. Results We evaluated three kernel-based applicability domain estimations using three different structured kernels on three virtual screening tasks. Each experiment consisted of the training of a kernel-based QSAR model using support vector regression and the ranking of a disjoint screening data set according to the predicted activity. For each prediction, the applicability of the model for the respective compound is quantitatively described using a score obtained by an applicability domain formulation. The suitability of the applicability domain estimation is evaluated by comparing the model performance on the subsets of the screening data sets obtained by different thresholds for the applicability scores. This comparison indicates that it is possible to separate the part of the chemspace, in which the model gives reliable predictions, from the part consisting of structures too dissimilar to the training set to apply the model successfully. A closer inspection reveals that the virtual screening performance of the model is considerably improved if half of the molecules, those with the lowest applicability scores, are omitted from the screening

  3. Estimation of the applicability domain of kernel-based machine learning models for virtual screening.

    Science.gov (United States)

    Fechner, Nikolas; Jahn, Andreas; Hinselmann, Georg; Zell, Andreas

    2010-03-11

    The virtual screening of large compound databases is an important application of structural-activity relationship models. Due to the high structural diversity of these data sets, it is impossible for machine learning based QSAR models, which rely on a specific training set, to give reliable results for all compounds. Thus, it is important to consider the subset of the chemical space in which the model is applicable. The approaches to this problem that have been published so far mostly use vectorial descriptor representations to define this domain of applicability of the model. Unfortunately, these cannot be extended easily to structured kernel-based machine learning models. For this reason, we propose three approaches to estimate the domain of applicability of a kernel-based QSAR model. We evaluated three kernel-based applicability domain estimations using three different structured kernels on three virtual screening tasks. Each experiment consisted of the training of a kernel-based QSAR model using support vector regression and the ranking of a disjoint screening data set according to the predicted activity. For each prediction, the applicability of the model for the respective compound is quantitatively described using a score obtained by an applicability domain formulation. The suitability of the applicability domain estimation is evaluated by comparing the model performance on the subsets of the screening data sets obtained by different thresholds for the applicability scores. This comparison indicates that it is possible to separate the part of the chemspace, in which the model gives reliable predictions, from the part consisting of structures too dissimilar to the training set to apply the model successfully. A closer inspection reveals that the virtual screening performance of the model is considerably improved if half of the molecules, those with the lowest applicability scores, are omitted from the screening. The proposed applicability domain formulations

  4. A Simple Forecasting Model Linking Macroeconomic Policy to Industrial Employment Demand.

    Science.gov (United States)

    Malley, James R.; Hady, Thomas F.

    A study detailed further a model linking monetary and fiscal policy to industrial employment in metropolitan and nonmetropolitan areas of four United States regions. The model was used to simulate the impacts on area and regional employment of three events in the economy: changing real gross national product (GNP) via monetary policy, holding the…

  5. A REGIONAL MODELING STRUCTURE FOR ASSESSING MANURE MANAGEMENT POLICIES: APPLICATION TO THE CHESAPEAKE BAY WATERSHED

    OpenAIRE

    Aillery, Marcel P.; Gollehon, Noel R.; Ribaudo, Marc; Breneman, Vincent E.

    2001-01-01

    A modeling framework addresses manure management policies within the Chesapeake Bay watershed. Policy focus is on manure-land application at agronomic rates, as proposed under the EPA/USDA Unified Strategy. Manure-nutrient flows are assessed subject to assimilative capacity of farmland. National data bases and GIS coverages facilitate model transferability to other watersheds.

  6. Foam Assisted WAG, Snorre Revisit with New Foam Screening Model

    DEFF Research Database (Denmark)

    Spirov, Pavel; Rudyk, Svetlana Nikolayevna; Khan, Arif

    2012-01-01

    of the simulation contributes to more precise planning of the schedule of water and gas injection, prediction of the injection results and evaluation of the method efficiency. The testing of the surfactant properties allows making grounded choice of surfactant to use. The analysis of the history match gives insight...... foam model was tested with sensitivity analysis on foam properties to provide a guideline for the history matching process (GOR alteration) of FAWAG Pilot of Snorre Field (Statoil). The aim was to check the authenticity of presented new foam model in commercial software whether it is implementable...... of the fluid flows control inside reservoir. The way; how specific properties control the time of gas arrival and values of GOR are described. The analyses of the improvements in the injection schedule are shown. With increasing number of CO2 and FAWAG methods in preparation worldwide, the use...

  7. Conceptual design of a regional water quality screening model

    International Nuclear Information System (INIS)

    Davis, M.J.

    1981-01-01

    This water quality assessment methodology is intended to predict concentrations at future times and to estimate the impacts on water quality of energy-related activities (including industrial boilers). Estimates of impacts on water quality at future times are based on incremental changes in pollutant inputs to the body water. Important features of the model are: use of measured concentrations to account for existing conditions; consideration of incremental changes in pollutant loads; emphasis on the energy sector and industrial boilers; analysis restricted to streams only; no attempt to fully account for pollutant behavior; and flexible design, so that future improvements can be incorporated. The basic approach is very similar to the one used by Argonne's ARQUAL model but will allow more complex pollutant behavior and more flexibility in use

  8. Modeling Security-Enhanced Linux Policy Specifications for Analysis (Preprint)

    National Research Council Canada - National Science Library

    Archer, Myla; Leonard, Elizabeth; Pradella, Matteo

    2003-01-01

    Security-Enhanced (SE) Linux is a modification of Linux initially released by NSA in January 2001 that provides a language for specifying Linux security policies and, as in the Flask architecture, a security server...

  9. Trade policy-making in a model of legislative bargaining

    Czech Academy of Sciences Publication Activity Database

    Celik, Levent; Karabay, B.; McLaren, J.

    2013-01-01

    Roč. 91, č. 2 (2013), s. 179-190 ISSN 0022-1996 Institutional support: RVO:67985998 Keywords : trade policy * multilateral legislative bargaining * political economy Subject RIV: AH - Economics Impact factor: 2.443, year: 2013

  10. Hydration of nail plate: a novel screening model for transungual drug permeation enhancers.

    Science.gov (United States)

    Chouhan, P; Saini, T R

    2012-10-15

    Drug delivery by topical route for the treatment of onychomycosis, a nail fungal infection, is challenging due to the unique barrier properties of the nail plate which imparts high resistance to the passage of antifungal drugs. Permeation enhancers are used in transungual formulations to improve the drug flux across the nail plate. Selection of the effective permeation enhancer among the available large pool of permeation enhancers is a difficult task. Screening the large number of permeation enhancers using conventional Franz diffusion cells is laborious and expensive. The objective of present study was to evolve a simple, accurate and rapid method for screening of transungual drug permeation enhancers based on the principle of hydration of nail plate. The permeation enhancer which affects the structural or physicochemical properties of nail plate would also affect their hydration capacity. Two screening procedures namely primary and secondary screenings were evolved wherein hydration and uptake of ciclopirox olamine by nail plates were measured. Hydration enhancement factor, HEF(24) and drug uptake enhancement factor, UEF(24) were determined for screening of 23 typical permeation enhancers. The Pearson's correlation coefficient between HEF(24) and UEF(24) was determined. A good agreement between the HEF(24) and UEF(24) data proved the validity of the proposed nail plate hydration model as a screening technique for permeation enhancers. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. A team care model of cervical 
screening in a general practice.

    Science.gov (United States)

    Rennie, Darryn; Boxsell, Jennifer; Pedretti, Kaye

    2015-07-01

    Cervical screening reduces the incidence and mortality rate of cervical cancer. General practices have opportunities to increase screening rates by modifying the model of service provided. We provide an example of team-based cervical screening in a general practice and report the effectiveness of invitation letters for women with no record of a Pap smear. The practice sent invitation letters to women with no record of a Pap smear (or reason for not requiring one) to attend a visit to a women's health clinic comprising a visit to a GP of choice and then a nurse to perform the smear. Practice cervical screening data were collected over 45 months to investigate the impact of invitation letters. The quality of Pap smears performed by nurses was recorded. The biennial cervical screening rate improved by 11%. The percentage of women with no Pap smear recorded was reduced from 41.71% to 27.99%. The quality of the smears taken by the nurses was above the nationwide average. The data show that invitation letters contributed to improved cervical screening and that nurses were highly effective team members in the collection of Pap smears.

  12. Cost Effectiveness of Screening Colonoscopy Depends on Adequate Bowel Preparation Rates - A Modeling Study.

    Directory of Open Access Journals (Sweden)

    James Kingsley

    Full Text Available Inadequate bowel preparation during screening colonoscopy necessitates repeating colonoscopy. Studies suggest inadequate bowel preparation rates of 20-60%. This increases the cost of colonoscopy for our society.The aim of this study is to determine the impact of inadequate bowel preparation rate on the cost effectiveness of colonoscopy compared to other screening strategies for colorectal cancer (CRC.A microsimulation model of CRC screening strategies for the general population at average risk for CRC. The strategies include fecal immunochemistry test (FIT every year, colonoscopy every ten years, sigmoidoscopy every five years, or stool DNA test every 3 years. The screening could be performed at private practice offices, outpatient hospitals, and ambulatory surgical centers.At the current assumed inadequate bowel preparation rate of 25%, the cost of colonoscopy as a screening strategy is above society's willingness to pay (<$50,000/QALY. Threshold analysis demonstrated that an inadequate bowel preparation rate of 13% or less is necessary before colonoscopy is considered more cost effective than FIT. At inadequate bowel preparation rates of 25%, colonoscopy is still more cost effective compared to sigmoidoscopy and stool DNA test. Sensitivity analysis of all inputs adjusted by ±10% showed incremental cost effectiveness ratio values were influenced most by the specificity, adherence, and sensitivity of FIT and colonoscopy.Screening colonoscopy is not a cost effective strategy when compared with fecal immunochemical test, as long as the inadequate bowel preparation rate is greater than 13%.

  13. Family Resilience in the Military: Definitions, Models, and Policies

    Science.gov (United States)

    2015-01-01

    Chartrand et al., 2008; Lester et al., 2010; Lincoln and Sweeten , 2011; Chandra et al., 2010; Chandra et al., 2011; Gibbs et al., 2008). Despite...for definitions of family resilience. Of these, 29 presented at least one definition with original content (i.e., a new definition or one building on...policies: (1) policies about programs that originally had different purposes, such as youth programs, which are then modified to address resilience or

  14. Utilizing high throughput screening data for predictive toxicology models: protocols and application to MLSCN assays

    Science.gov (United States)

    Guha, Rajarshi; Schürer, Stephan C.

    2008-06-01

    Computational toxicology is emerging as an encouraging alternative to experimental testing. The Molecular Libraries Screening Center Network (MLSCN) as part of the NIH Molecular Libraries Roadmap has recently started generating large and diverse screening datasets, which are publicly available in PubChem. In this report, we investigate various aspects of developing computational models to predict cell toxicity based on cell proliferation screening data generated in the MLSCN. By capturing feature-based information in those datasets, such predictive models would be useful in evaluating cell-based screening results in general (for example from reporter assays) and could be used as an aid to identify and eliminate potentially undesired compounds. Specifically we present the results of random forest ensemble models developed using different cell proliferation datasets and highlight protocols to take into account their extremely imbalanced nature. Depending on the nature of the datasets and the descriptors employed we were able to achieve percentage correct classification rates between 70% and 85% on the prediction set, though the accuracy rate dropped significantly when the models were applied to in vivo data. In this context we also compare the MLSCN cell proliferation results with animal acute toxicity data to investigate to what extent animal toxicity can be correlated and potentially predicted by proliferation results. Finally, we present a visualization technique that allows one to compare a new dataset to the training set of the models to decide whether the new dataset may be reliably predicted.

  15. Applying Statistical Models to Mammographic Screening Data to Understand Growth and Progression of Ductal Carcinoma in Situ

    National Research Council Canada - National Science Library

    Gertig, Dorota M; Erbas, Bircan; Bymes, Gram; Dowty, James

    2005-01-01

    ... IS. Similar results were found for histological grade. We have developed a computer simulation for mammographic screening data which models progression and detection of Ductal carcinoma in situ...

  16. A Three-groups Model for High Throughput Survival Screens

    Science.gov (United States)

    Shaby, Benjamin A.; Skibinski, Gaia; Ando, Michael; LaDow, Eva S.; Finkbeiner, Steven

    2016-01-01

    Summary Amyotrophic lateral sclerosis (ALS) is a neurodegenerative condition characterized by the progressive deterioration of motor neurons in the cortex and spinal cord. Using an automated robotic microscope platform that enables the longitudinal tracking of thousands of single neurons, we examine the effects a large library of compounds on modulating the survival of primary neurons expressing a mutation known to cause ALS. The goal of our analysis is to identify the few potentially beneficial compounds among the many assayed, the vast majority of which do not extend neuronal survival. This resembles the large-scale simultaneous inference scenario familiar from microarray analysis, but transferred to the survival analysis setting due to the novel experimental setup. We apply a three component mixture model to censored survival times of thousands of individual neurons subjected to hundreds of different compounds. The shrinkage induced by our model significantly improves performance in simulations relative to performing treatment-wise survival analysis and subsequent multiple testing adjustment. Our analysis identified compounds that provide insight into potential novel therapeutic strategies for ALS. PMID:26821783

  17. Suomi NPP VIIRS solar diffuser screen transmittance model and its applications.

    Science.gov (United States)

    Lei, Ning; Xiong, Xiaoxiong; Mcintire, Jeff

    2017-11-01

    The visible infrared imaging radiometer suite on the Suomi National Polar-orbiting Partnership satellite calibrates its reflective solar bands through observations of a sunlit solar diffuser (SD) panel. Sunlight passes through a perforated plate, referred to as the SD screen, before reaching the SD. It is critical to know whether the SD screen transmittance measured prelaunch is accurate. Several factors such as misalignments of the SD panel and the measurement apparatus could lead to errors in the measured transmittance and thus adversely impact on-orbit calibration quality through the SD. We develop a mathematical model to describe the transmittance as a function of the angles that incident light makes with the SD screen, and apply the model to fit the prelaunch measured transmittance. The results reveal that the model does not reproduce the measured transmittance unless the size of the apertures in the SD screen is quite different from the design value. We attribute the difference to the orientation alignment errors for the SD panel and the measurement apparatus. We model the alignment errors and apply our transmittance model to fit the prelaunch transmittance to retrieve the "true" transmittance. To use this model correctly, we also examine the finite source size effect on the transmittance. Furthermore, we compare the product of the retrieved "true" transmittance and the prelaunch SD bidirectional reflectance distribution function (BRDF) value to the value derived from on-orbit data to determine whether the prelaunch SD BRDF value is relatively accurate. The model is significant in that it can evaluate whether the SD screen transmittance measured prelaunch is accurate and help retrieve the true transmittance from the transmittance with measurement errors, consequently resulting in a more accurate sensor data product by the same amount.

  18. Turkish translation and adaptation of Champion's Health Belief Model Scales for breast cancer mammography screening.

    Science.gov (United States)

    Yilmaz, Meryem; Sayin, Yazile Yazici

    2014-07-01

    To examine the translation and adaptation process from English to Turkish and the validity and reliability of the Champion's Health Belief Model Scales for Mammography Screening. Its aim (1) is to provide data about and (2) to assess Turkish women's attitudes and behaviours towards mammography. The proportion of women who have mammography is lower in Turkey. The Champion's Health Belief Model Scales for Mammography Screening-Turkish version can be helpful to determine Turkish women's health beliefs, particularly about mammography. Cross-sectional design was used to collect survey data from Turkish women: classical measurement method. The Champion's Health Belief Model Scales for Mammography Screening was translated from English to Turkish. Again, it was back translated into English. Later, the meaning and clarity of the scale items were evaluated by a bilingual group representing the culture of the target population. Finally, the tool was evaluated by two bilingual professional researchers in terms of content validity, translation validity and psychometric estimates of the validity and reliability. The analysis included a total of 209 Turkish women. The validity of the scale was confirmed by confirmatory factor analysis and criterion-related validity testing. The Champion's Health Belief Model Scales for Mammography Screening aligned to four factors that were coherent and relatively independent of each other. There was a statistically significant relationship among all of the subscale items: the positive and high correlation of the total item test score and high Cronbach's α. The scale has a strong stability over time: the Champion's Health Belief Model Scales for Mammography Screening demonstrated acceptable preliminary values of reliability and validity. The Champion's Health Belief Model Scales for Mammography Screening is both a reliable and valid instrument that can be useful in measuring the health beliefs of Turkish women. It can be used to provide data

  19. Targeted screening of individuals at high risk for pancreatic cancer: results of a simulation model.

    Science.gov (United States)

    Pandharipande, Pari V; Heberle, Curtis; Dowling, Emily C; Kong, Chung Yin; Tramontano, Angela; Perzan, Katherine E; Brugge, William; Hur, Chin

    2015-04-01

    To identify when, from the standpoint of relative risk, magnetic resonance (MR) imaging-based screening may be effective in patients with a known or suspected genetic predisposition to pancreatic cancer. The authors developed a Markov model of pancreatic ductal adenocarcinoma (PDAC). The model was calibrated to National Cancer Institute Surveillance, Epidemiology, and End Results registry data and informed by the literature. A hypothetical screening strategy was evaluated in which all population individuals underwent one-time MR imaging screening at age 50 years. Screening outcomes for individuals with an average risk for PDAC ("base case") were compared with those for individuals at an increased risk to assess for differential benefits in populations with a known or suspected genetic predisposition. Effects of varying key inputs, including MR imaging performance, surgical mortality, and screening age, were evaluated with a sensitivity analysis. RESULTS In the base case, screening resulted in a small number of cancer deaths averted (39 of 100 000 men, 38 of 100 000 women) and a net decrease in life expectancy (-3 days for men, -4 days for women), which was driven by unnecessary pancreatic surgeries associated with false-positive results. Life expectancy gains were achieved if an individual's risk for PDAC exceeded 2.4 (men) or 2.7 (women) times that of the general population. When relative risk increased further, for example to 30 times that of the general population, averted cancer deaths and life expectancy gains increased substantially (1219 of 100 000 men, life expectancy gain: 65 days; 1204 of 100 000 women, life expectancy gain: 71 days). In addition, results were sensitive to MR imaging specificity and the surgical mortality rate. Although PDAC screening with MR imaging for the entire population is not effective, individuals with even modestly increased risk may benefit. © RSNA, 2014 Online supplemental material is available for this article.

  20. [Screening program for cervical cancer: public policies and experiences of actors who implement the program in the state of Veracruz, Mexico].

    Science.gov (United States)

    González, Zuanilda Mendoza

    2017-01-01

    The aim of this article is to analyze the way in which the Screening Program for Cervical Cancer is carried out in a dysplasia clinic and related health centers in the state of Veracruz, through the representations and practices of the social actors who implement the program. In order to do so, in-depth interviews and observations of the practices of health service providers were carried out during different periods over the course of three years, from 2009 to 2011. Through the information obtained, the article explores the difficulties, achievements and results of this program as part of a public policy. Although a priority of public health policy is to see the whole population benefit from preventive and curative health care services, evidence shows that marginalized populations are not benefitted by such programs; such information does not however seem to permeate popular and medical knowledge.

  1. Screening enterprising personality in youth: an empirical model.

    Science.gov (United States)

    Suárez-Álvarez, Javier; Pedrosa, Ignacio; García-Cueto, Eduardo; Muñiz, José

    2014-02-20

    Entrepreneurial attitudes of individuals are determined by different variables, some of them related to the cognitive and personality characteristics of the person, and others focused on contextual aspects. The aim of this study is to review the essential dimensions of enterprising personality and develop a test that will permit their thorough assessment. Nine dimensions were identified: achievement motivation, risk taking, innovativeness, autonomy, internal locus of control, external locus of control, stress tolerance, self-efficacy and optimism. For the assessment of these dimensions, 161 items were developed which were applied to a sample of 416 students, 54% male and 46% female (M = 17.89 years old, SD = 3.26). After conducting several qualitative and quantitative analyses, the final test was composed of 127 items with acceptable psychometric properties. Alpha coefficients for the subscales ranged from .81 to .98. The validity evidence relative to the content was provided by experts (V = .71, 95% CI = .56 - .85). Construct validity was assessed using different factorial analyses, obtaining a dimensional structure in accordance with the proposed model of nine interdependent dimensions as well as a global factor that groups these nine dimensions (explained variance = 49.07%; χ2/df = 1.78; GFI= .97; SRMR = .07). Nine out of the 127 items showed Differential Item Functioning as a function of gender (p .035). The results obtained are discussed and future lines of research analyzed.

  2. Physical environments, policies and practices for physical activity and screen-based sedentary behaviour among preschoolers within child care centres in Melbourne, Australia and Kingston, Canada.

    Science.gov (United States)

    Hinkley, T; Carson, V; Hesketh, K D

    2015-01-01

    Characteristics of preschool and child care centres have previously been shown to be associated with children's health behaviours such as physical activity and screen-based sedentary behaviour. This paper investigates differences in physical environments, policies and practices between child care centres in Melbourne, Australia and Kingston, Canada which may be associated with such behaviours. Audits of child care centres were undertaken by trained research assistants for the Healthy Active Preschool and Primary Years (Melbourne, Australia; n = 136) study and the Healthy Living Habits in Pre-School Children (Kingston, Canada; n = 46) study. Twenty-one of the audit items (nine physical environment; 12 policies and practices) were assessed in both samples. Example items included outdoor play and shaded areas, availability of equipment, physical activity instruction for children and staff, opportunities to use electronic media and staff/child interaction during physical activity time. Analyses were completed using SAS version 9.2. Compared with Australian centres, a higher per cent of Canadian centres had a formal physical activity policy, reported children sat more frequently for 30 min or more and allowed children to watch television. A higher per cent of Australian centres provided an indoor area for physical activity, shade outdoors and physical activity education to staff. Children in Australian centres had access to more fixed play equipment and spent more time outdoors than in Canadian centres. These findings may help inform the development of best practice and policy guidelines to enhance opportunities for healthy levels of physical activity and screen-based sedentary behaviour within child care centres in both countries. © 2014 John Wiley & Sons Ltd.

  3. Footprint (A Screening Model for Estimating the Area of a Plume Produced from Gasoline Containing Ethanol

    Science.gov (United States)

    FOOTPRINT is a simple and user-friendly screening model to estimate the length and surface area of BTEX plumes in ground water produced from a spill of gasoline that contains ethanol. Ethanol has a potential negative impact on the natural biodegradation of BTEX compounds in groun...

  4. Screening and vaccination as determined by the Social Ecological Model and the Theory of Triadic Influence

    NARCIS (Netherlands)

    Nyambe, Anayawa; Hal, Van Guido; Kampen, Jarl K.

    2016-01-01

    Background: Vaccination and screening are forms of primary and secondary prevention methods. These methods are recommended for controlling the spread of a vast number of diseases and conditions. To determine the most effective preventive methods to be used by a society, multi-level models have

  5. Risk prediction models for selection of lung cancer screening candidates: A retrospective validation study

    NARCIS (Netherlands)

    K. ten Haaf (Kevin); J. Jeon (Jihyoun); M.C. Tammemagi (Martin); S.S. Han (Summer); C.Y. Kong (Chung Yin); S.K. Plevritis (Sylvia); E. Feuer (Eric); H.J. de Koning (Harry); E.W. Steyerberg (Ewout W.); R. Meza (Rafael)

    2017-01-01

    textabstractBackground: Selection of candidates for lung cancer screening based on individual risk has been proposed as an alternative to criteria based on age and cumulative smoking exposure (pack-years). Nine previously established risk models were assessed for their ability to identify those most

  6. Life-Stage Physiologically-Based Pharmacokinetic (PBPK) Model Applications to Screen Environmental Hazards.

    Science.gov (United States)

    This presentation discusses methods used to extrapolate from in vitro high-throughput screening (HTS) toxicity data for an endocrine pathway to in vivo for early life stages in humans, and the use of a life stage PBPK model to address rapidly changing physiological parameters. A...

  7. Using the Cascade Model to Improve Antenatal Screening for the Hemoglobin Disorders

    Science.gov (United States)

    Gould, Dinah; Papadopoulos, Irena; Kelly, Daniel

    2012-01-01

    Introduction: The inherited hemoglobin disorders constitute a major public health problem. Facilitators (experienced hemoglobin counselors) were trained to deliver knowledge and skills to "frontline" practitioners to enable them to support parents during antenatal screening via a cascade (train-the-trainer) model. Objectives of…

  8. An oil demand and supply model incorporating monetary policy

    International Nuclear Information System (INIS)

    Askari, Hossein; Krichene, Noureddine

    2010-01-01

    Oil price inflation may have had a significant role in pushing the world economy into its worst post-war recession during 2008-2009. Reserve currency central banks pursued an overly expansionary monetary policy during 2001-2009, in the form of low or negative real interest rates and accompanied by a rapidly falling US dollar, while paying inadequate attention to the destabilizing effects on oil markets. In this paper, we show that monetary policy variables, namely key interest rates and the US dollar exchange rate, had a powerful effect on oil markets. World oil demand was significantly influenced by interest and dollar exchange rates, while oil supply was rigid. Oil demand and supply have very low price elasticity and this characteristic makes oil prices highly volatile and subject to wider fluctuations than the prices of other commodities. Aggressive monetary policy would stimulate oil demand, however, it would be met with rigid oil supply and would turn inflationary and disruptive to economic growth if there was little excess capacity in oil output. We argue that a measure of stability in oil markets cannot be achieved unless monetary policy is restrained and real interest rates become significantly positive. Monetary tightening during 1979-1982 might imply that monetary policy has to be restrained for a long period and with high interest rates in order to bring stability back to oil markets. (author)

  9. Knowledge brokering on emissions modelling in Strategic Environmental Assessment of Estonian energy policy with special reference to the LEAP model

    Energy Technology Data Exchange (ETDEWEB)

    Kuldna, Piret, E-mail: piret.kuldna@seit.ee [Stockholm Environment Institute Tallinn Centre, Lai 34, Tallinn 10133 (Estonia); Peterson, Kaja [Stockholm Environment Institute Tallinn Centre, Lai 34, Tallinn 10133 (Estonia); Kuhi-Thalfeldt, Reeli [Stockholm Environment Institute Tallinn Centre, Lai 34, Tallinn 10133 (Estonia); Tallinn University of Technology, Ehitajate tee 5, Tallinn 19086 (Estonia)

    2015-09-15

    Strategic Environmental Assessment (SEA) serves as a platform for bringing together researchers, policy developers and other stakeholders to evaluate and communicate significant environmental and socio-economic effects of policies, plans and programmes. Quantitative computer models can facilitate knowledge exchange between various parties that strive to use scientific findings to guide policy-making decisions. The process of facilitating knowledge generation and exchange, i.e. knowledge brokerage, has been increasingly explored, but there is not much evidence in the literature on how knowledge brokerage activities are used in full cycles of SEAs which employ quantitative models. We report on the SEA process of the national energy plan with reflections on where and how the Long-range Energy Alternatives Planning (LEAP) model was used for knowledge brokerage on emissions modelling between researchers and policy developers. Our main suggestion is that applying a quantitative model not only in ex ante, but also ex post scenario modelling and associated impact assessment can facilitate systematic and inspiring knowledge exchange process on a policy problem and capacity building of participating actors. - Highlights: • We examine the knowledge brokering on emissions modelling between researchers and policy developers in a full cycle of SEA. • Knowledge exchange process can evolve at any modelling stage within SEA. • Ex post scenario modelling enables systematic knowledge exchange and learning on a policy problem.

  10. Knowledge brokering on emissions modelling in Strategic Environmental Assessment of Estonian energy policy with special reference to the LEAP model

    International Nuclear Information System (INIS)

    Kuldna, Piret; Peterson, Kaja; Kuhi-Thalfeldt, Reeli

    2015-01-01

    Strategic Environmental Assessment (SEA) serves as a platform for bringing together researchers, policy developers and other stakeholders to evaluate and communicate significant environmental and socio-economic effects of policies, plans and programmes. Quantitative computer models can facilitate knowledge exchange between various parties that strive to use scientific findings to guide policy-making decisions. The process of facilitating knowledge generation and exchange, i.e. knowledge brokerage, has been increasingly explored, but there is not much evidence in the literature on how knowledge brokerage activities are used in full cycles of SEAs which employ quantitative models. We report on the SEA process of the national energy plan with reflections on where and how the Long-range Energy Alternatives Planning (LEAP) model was used for knowledge brokerage on emissions modelling between researchers and policy developers. Our main suggestion is that applying a quantitative model not only in ex ante, but also ex post scenario modelling and associated impact assessment can facilitate systematic and inspiring knowledge exchange process on a policy problem and capacity building of participating actors. - Highlights: • We examine the knowledge brokering on emissions modelling between researchers and policy developers in a full cycle of SEA. • Knowledge exchange process can evolve at any modelling stage within SEA. • Ex post scenario modelling enables systematic knowledge exchange and learning on a policy problem

  11. Current levels of gonorrhoea screening in MSM in Belgium may have little effect on prevalence: a modelling study.

    Science.gov (United States)

    Buyze, J; Vanden Berghe, W; Hens, N; Kenyon, C

    2018-02-01

    There is considerable uncertainty as to the effectiveness of Neisseria gonorrhoeae (NG) screening in men who have sex with men. It is important to ensure that screening has benefits that outweigh the risks of increased antibiotics resistance. We develop a mathematical model to estimate the effectiveness of screening on prevalence. Separable Temporal Exponential family Random Graph Models are used to model the sexual relationships network, both with main and casual partners. Next, the transmission of Gonorrhoea is simulated on this network. The models are implemented using the R package 'statnet', which we adapted among other things to incorporate infection status at the pharynx, urethra and rectum separately and to distinguish between anal sex, oral sex and rimming. The different screening programmes compared are no screening, 3.5% of the population screened, 32% screened and 50% screened. The model simulates day-by-day evolution for 10 years of a population of 10 000. If half of the population would be screened, the prevalence in the pharynx decreases from 11.9% to 10.2%. We conclude that the limited impact of screening on NG prevalence may not outweigh the increased risk of antibiotic resistance.

  12. Systems Thinking and Simulation Modeling to Inform Childhood Obesity Policy and Practice.

    Science.gov (United States)

    Powell, Kenneth E; Kibbe, Debra L; Ferencik, Rachel; Soderquist, Chris; Phillips, Mary Ann; Vall, Emily Anne; Minyard, Karen J

    In 2007, 31.7% of Georgia adolescents in grades 9-12 were overweight or obese. Understanding the impact of policies and interventions on obesity prevalence among young people can help determine statewide public health and policy strategies. This article describes a systems model, originally launched in 2008 and updated in 2014, that simulates the impact of policy interventions on the prevalence of childhood obesity in Georgia through 2034. In 2008, using information from peer-reviewed reports and quantitative estimates by experts in childhood obesity, physical activity, nutrition, and health economics and policy, a group of legislators, legislative staff members, and experts trained in systems thinking and system dynamics modeling constructed a model simulating the impact of policy interventions on the prevalence of childhood obesity in Georgia through 2034. Use of the 2008 model contributed to passage of a bill requiring annual fitness testing of schoolchildren and stricter enforcement of physical education requirements. We updated the model in 2014. With no policy change, the updated model projects that the prevalence of obesity among children and adolescents aged ≤18 in Georgia would hold at 18% from 2014 through 2034. Mandating daily school physical education (which would reduce prevalence to 12%) and integrating moderate to vigorous physical activity into elementary classrooms (which would reduce prevalence to 10%) would have the largest projected impact. Enacting all policies simultaneously would lower the prevalence of childhood obesity from 18% to 3%. Systems thinking, especially with simulation models, facilitates understanding of complex health policy problems. Using a simulation model to educate legislators, educators, and health experts about the policies that have the greatest short- and long-term impact should encourage strategic investment in low-cost, high-return policies.

  13. Validation of periodontitis screening model using sociodemographic, systemic, and molecular information in a Korean population.

    Science.gov (United States)

    Kim, Hyun-Duck; Sukhbaatar, Munkhzaya; Shin, Myungseop; Ahn, Yoo-Been; Yoo, Wook-Sung

    2014-12-01

    This study aims to evaluate and validate a periodontitis screening model that includes sociodemographic, metabolic syndrome (MetS), and molecular information, including gingival crevicular fluid (GCF), matrix metalloproteinase (MMP), and blood cytokines. The authors selected 506 participants from the Shiwha-Banwol cohort: 322 participants from the 2005 cohort for deriving the screening model and 184 participants from the 2007 cohort for its validation. Periodontitis was assessed by dentists using the community periodontal index. Interleukin (IL)-6, IL-8, and tumor necrosis factor-α in blood and MMP-8, -9, and -13 in GCF were assayed using enzyme-linked immunosorbent assay. MetS was assessed by physicians using physical examination and blood laboratory data. Information about age, sex, income, smoking, and drinking was obtained by interview. Logistic regression analysis was applied to finalize the best-fitting model and validate the model using sensitivity, specificity, and c-statistics. The derived model for periodontitis screening had a sensitivity of 0.73, specificity of 0.85, and c-statistic of 0.86 (P validated model were 0.64, 0.91, and 0.83 (P periodontitis. A future prospective study is indicated for evaluating this model's ability to predict the occurrence of periodontitis.

  14. Assimilation of tourism satellite accounts and applied general equilibrium models to inform tourism policy analysis

    OpenAIRE

    Rossouw, Riaan; Saayman, Melville

    2011-01-01

    Historically, tourism policy analysis in South Africa has posed challenges to accurate measurement. The primary reason for this is that tourism is not designated as an 'industry' in standard economic accounts. This paper therefore demonstrates the relevance and need for applied general equilibrium (AGE) models to be completed and extended through an integration with tourism satellite accounts (TSAs) as a tool for policy makers (especially tourism policy makers) in South Africa. The paper sets...

  15. Experiences with a dialogue process between policy makers and global modellers

    International Nuclear Information System (INIS)

    Van Daalen, C.E.; Thissen, W.A.H.; Berk, M.M.

    1998-01-01

    Between 1995 and 1997, a series of five workshops, henceforth called the Delft process, took place with the aim to explore and enhance use of the IMAGE 2 model to support international climate negotiations. The IMAGE 2 model is a multi-disciplinary, integrated model designed to simulate the dynamics of the global society-biosphere-climate system. The workshops facilitated a dialogue between policy makers and scientists involved in the development and applications of the IMAGE 2 model. In this way, policy makers would benefit from the policy makers on how to improve the policy relevance of the IMAGE 2 model. The evaluation at the end of the workshop series showed that participants have used information from the workshop at international negotiation conferences and in preparation of policy documents. The process shows that creating a forum for direct science-policy interactions can be very useful and productive, and has confirmed the importance of creating an open and constructive atmosphere between policy makers, and between policy makers and analysts, to enhance utilisation of scientific knowledge. The authors' analysis also suggests that many factors have to be 'in the right position at the right time and place' to achieve such a success, and that it is difficult to prevent the occurrence of biases in processes like this. 33 refs

  16. The application of system dynamics modelling to environmental health decision-making and policy - a scoping review.

    Science.gov (United States)

    Currie, Danielle J; Smith, Carl; Jagals, Paul

    2018-03-27

    Policy and decision-making processes are routinely challenged by the complex and dynamic nature of environmental health problems. System dynamics modelling has demonstrated considerable value across a number of different fields to help decision-makers understand and predict the dynamic behaviour of complex systems in support the development of effective policy actions. In this scoping review we investigate if, and in what contexts, system dynamics modelling is being used to inform policy or decision-making processes related to environmental health. Four electronic databases and the grey literature were systematically searched to identify studies that intersect the areas environmental health, system dynamics modelling, and decision-making. Studies identified in the initial screening were further screened for their contextual, methodological and application-related relevancy. Studies deemed 'relevant' or 'highly relevant' according to all three criteria were included in this review. Key themes related to the rationale, impact and limitation of using system dynamics in the context of environmental health decision-making and policy were analysed. We identified a limited number of relevant studies (n = 15), two-thirds of which were conducted between 2011 and 2016. The majority of applications occurred in non-health related sectors (n = 9) including transportation, public utilities, water, housing, food, agriculture, and urban and regional planning. Applications were primarily targeted at micro-level (local, community or grassroots) decision-making processes (n = 9), with macro-level (national or international) decision-making to a lesser degree. There was significant heterogeneity in the stated rationales for using system dynamics and the intended impact of the system dynamics model on decision-making processes. A series of user-related, technical and application-related limitations and challenges were identified. None of the reported limitations or challenges

  17. The Role Of Modeling Assumptions And Policy Instruments in Evaluating The Global Implications Of U.S. Biofuel Policies

    Energy Technology Data Exchange (ETDEWEB)

    Oladosu, Gbadebo A [ORNL; Kline, Keith L [ORNL

    2010-01-01

    The primary objective of current U.S. biofuel law the Energy Independence and Security Act of 2007 (EISA) is to reduce dependence on imported oil, but the law also requires biofuels to meet carbon emission reduction thresholds relative to petroleum fuels. EISA created a renewable fuel standard with annual targets for U.S. biofuel use that climb gradually from 9 billion gallons per year in 2008 to 36 billion gallons (or about 136 billion liters) of biofuels per year by 2022. The most controversial aspects of the biofuel policy have centered on the global social and environmental implications of its potential land use effects. In particular, there is an ongoing debate about whether indirect land use change (ILUC) make biofuels a net source, rather sink, of carbon emissions. However, estimates of ILUC induced by biofuel production and use can only be inferred through modeling. This paper evaluates how model structure, underlying assumptions, and the representation of policy instruments influence the results of U.S. biofuel policy simulations. The analysis shows that differences in these factors can lead to divergent model estimates of land use and economic effects. Estimates of the net conversion of forests and grasslands induced by U.S. biofuel policy range from 0.09 ha/1000 gallons described in this paper to 0.73 ha/1000 gallons from early studies in the ILUC change debate. We note that several important factors governing LUC change remain to be examined. Challenges that must be addressed to improve global land use change modeling are highlighted.

  18. An analysis of household waste management policy using system dynamics modelling.

    Science.gov (United States)

    Inghels, Dirk; Dullaert, Wout

    2011-04-01

    This paper analyses the Flemish household waste management policy. Based on historical data from the period 1991-2006, literature reviews and interviews, both mathematical and descriptive relationships are derived that describe Flemish waste collection, reuse, recycling and disposal behaviour. This provides insights into how gross domestic product (GDP), population and selective collection behaviour have influenced household waste production and collection over time. These relationships are used to model the dynamic relationships underlying household waste management in Flanders by using a system dynamics (SD) modelling approach. Where most SD models in literature are conceptual and descriptive, in the present study a real-life case with both correlational and descriptive relationships was modelled for Flanders, a European region with an outstanding waste management track record. This model was used to evaluate the current Flemish household waste management policy based on the principles of the waste hierarchy, also referred as the Lansink ranking. The results show that Flemish household waste targets up to 2015 can be achieved by the current waste policy measures. It also shows the sensitivity of some key policy parameters such as prevention and reuse. Given the general nature of the model and its limited data requirements, the authors believe that the approach implemented in this model can also assist waste policy makers in other regions or countries to meet their policy targets by simulating the effect of their current and potential household waste policy measures.

  19. A prediction model for advanced colorectal neoplasia in an asymptomatic screening population.

    Directory of Open Access Journals (Sweden)

    Sung Noh Hong

    Full Text Available An electronic medical record (EMR database of a large unselected population who received screening colonoscopies may minimize sampling error and represent real-world estimates of risk for screening target lesions of advanced colorectal neoplasia (CRN. Our aim was to develop and validate a prediction model for assessing the probability of advanced CRN using a clinical data warehouse.A total of 49,450 screenees underwent their first colonoscopy as part of a health check-up from 2002 to 2012 at Samsung Medical Center, and the dataset was constructed by means of natural language processing from the computerized EMR system. The screenees were randomized into training and validation sets. The prediction model was developed using logistic regression. The model performance was validated and compared with existing models using area under receiver operating curve (AUC analysis.In the training set, age, gender, smoking duration, drinking frequency, and aspirin use were identified as independent predictors for advanced CRN (adjusted P < .01. The developed model had good discrimination (AUC = 0.726 and was internally validated (AUC = 0.713. The high-risk group had a 3.7-fold increased risk of advanced CRN compared to the low-risk group (1.1% vs. 4.0%, P < .001. The discrimination performance of the present model for high-risk patients with advanced CRN was better than that of the Asia-Pacific Colorectal Screening score (AUC = 0.678, P < .001 and Schroy's CAN index (AUC = 0.672, P < .001.The present 5-item risk model can be calculated readily using a simple questionnaire and can identify the low- and high-risk groups of advanced CRN at the first screening colonoscopy. This model may increase colorectal cancer risk awareness and assist healthcare providers in encouraging the high-risk group to undergo a colonoscopy.

  20. Breast cancer screening behaviors among Korean American immigrant women: findings from the Health Belief Model.

    Science.gov (United States)

    Lee, Hee Yun; Stange, Mia Ju; Ahluwalia, Jasjit S

    2015-11-01

    This study examined the utilization of clinical breast examinations (CBEs) and mammograms among Korean American immigrant women and investigated how the six constructs of Health Belief Model (HBM) are associated with the receipt of breast cancer screening. Using a quota sampling strategy, 202 Korean American immigrant women were recruited in metropolitan areas in the northeastern United States. Approximately 64% of the participants reported having had at least one CBE in their lifetime, and about 81% of the sample had undergone at least one mammogram in their lifetime. Women who perceived themselves to be susceptible to breast cancer were more likely to have undergone a CBE, and women who had lower barriers to screening or demonstrated a higher level of confidence were more likely than their counterparts to undergo a mammogram. Findings suggest that HBM constructs such as susceptibility, barriers, and confidence should be considered when designing interventions aimed at promoting breast cancer screening. © The Author(s) 2014.

  1. Pharmacophore modeling improves virtual screening for novel peroxisome proliferator-activated receptor-gamma ligands

    Science.gov (United States)

    Lewis, Stephanie N.; Garcia, Zulma; Hontecillas, Raquel; Bassaganya-Riera, Josep; Bevan, David R.

    2015-05-01

    Peroxisome proliferator-activated receptor-gamma (PPARγ) is a nuclear hormone receptor involved in regulating various metabolic and immune processes. The PPAR family of receptors possesses a large binding cavity that imparts promiscuity of ligand binding not common to other nuclear receptors. This feature increases the challenge of using computational methods to identify PPAR ligands that will dock favorably into a structural model. Utilizing both ligand- and structure-based pharmacophore methods, we sought to improve agonist prediction by grouping ligands according to pharmacophore features, and pairing models derived from these features with receptor structures for docking. For 22 of the 33 receptor structures evaluated we observed an increase in true positive rate (TPR) when screening was restricted to compounds sharing molecular features found in rosiglitazone. A combination of structure models used for docking resulted in a higher TPR (40 %) when compared to docking with a single structure model (marketed drug database verified the predictive ability of the selected structure models. This study highlights the steps necessary to improve screening for PPARγ ligands using multiple structure models, ligand-based pharmacophore data, evaluation of protein-ligand interactions, and comparison of docking datasets. The unique combination of methods presented here holds potential for more efficient screening of compounds with unknown affinity for PPARγ that could serve as candidates for therapeutic development.

  2. Models for Determining the Efficiency of Student Loans Policies

    Science.gov (United States)

    Dente, Bruno; Piraino, Nadia

    2011-01-01

    For both efficiency and equity reasons, student loans schemes have been introduced by several countries. Empirical work has been carried out in order to measure the effectiveness of these policies, but, with few exceptions, their results are not comparable because of their concentration on specific aspects. The present work suggests a…

  3. Trade policy-making in a model of legislative bargaining

    Czech Academy of Sciences Publication Activity Database

    Celik, Levent; Karabay, Bilgehan; McLaren, J.

    2013-01-01

    Roč. 91, č. 2 (2013), s. 179-190 ISSN 0022-1996 R&D Projects: GA ČR(CZ) GAP402/12/0666 Grant - others:UK(CZ) UNCE 204005/2012 Institutional support: PRVOUK-P23 Keywords : trade policy * multilateral legislative bargaining * political economy Subject RIV: AH - Economics Impact factor: 2.443, year: 2013

  4. Integrated Climate Change Modelling and Policy Linkages for ...

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

    The project will consolidate the collective experience of CCW recipients from Africa, Asia, and Latin America and the Caribbean to develop and test a framework designed to overcome the mismatch between supply-driven climate research and demand-driven planning and policy. The project team will identify leading ...

  5. A problem solving model for regulatory policy making

    NARCIS (Netherlands)

    Boer, A.; van Engers, T.; Sileno, G.; Wyner, A.; Benn, N.

    2011-01-01

    In this paper we discuss how the interests and field theory promoted by public administration as a stakeholder in policy argumentation, directly arise from its problem solving activities, using the framework for public administration problem solving we proposed in [1,2]. We propose that calls for

  6. Palliative care policy analysis in Iran: A conceptual model

    Directory of Open Access Journals (Sweden)

    Mojgan Ansari

    2018-01-01

    Full Text Available Background: Palliative care programs are rapidly evolving for patients with life-threatening illnesses. Increased and earlier access for facilities is a subject of growing importance in health services, policy, and research. Aim: This study was conducted to explain stakeholders' perceptions of the factors affecting the design of such a palliative care system and its policy analysis. Methodology: Semi-structured in-depth interviews conducted following purposive sampling of the participants. Twenty-two participants were included in the study. The interviews were analyzed using qualitative-directed content analysis based on "policy analysis triangle" framework. Results: The findings showed the impact of four categories, namely context (political, social, and structural feasibility, content (target setting, process (attracting stakeholder participation, the standardization of care, and education management, and actors (the Ministry of Health and Medical Education, health-care providers, and volunteers in the analysis of the palliative care policies of Iran. Conclusion: In the past 6 years, attention to palliative care has increased significantly as a result of the National Cancer Research Network with the support of the Ministry of Health. The success of health system plan requires great attention to its aspects of social, political, and executive feasibility. Careful management by policymakers of different stakeholders is vital to ensure support for any national plan, but this is challenging to achieve.

  7. The Stress Check Program: a new national policy for monitoring and screening psychosocial stress in the workplace in Japan.

    Science.gov (United States)

    Kawakami, Norito; Tsutsumi, Akizumi

    2016-01-01

    The Japanese government launched a new occupational health policy called the Stress Check Program. This program mandates that all workplaces with 50 or more employees conduct the Stress Check Program for workers at least once a year. This article gives a brief overview and critical review of the program. We reviewed relevant laws, guidelines, and manuals, as well as the policy development process. The policy and the components of the program were compared using available scientific evidence and trends in the management of psychosocial factors at work according to the policies and guidelines of international bodies and European countries. The process of program policy development was based on a discussion among employer and employee representatives, occupational health professionals, and mental health experts. Scientific evidence shows that mandated components of the program (i.e., feedback of stress survey results and physician's interview) may be ineffective. However, additional components recommended to employers, such as stress management skill provision and work environment improvement, in conjunction with the program may be effective in improving psychosocial stress at work. The Stress Check Program is unique compared with the global trend for psychosocial risk management because it focuses on the assessment of stress among individual workers. The new program may be effective in improving worker mental health by facilitating the psychosocial risk management approach in Japan. Concerns regarding the program include mass leakage of collected information, and possible disadvantages for workers labeled as having high stress.

  8. Which strategies reduce breast cancer mortality most? Collaborative modeling of optimal screening, treatment, and obesity prevention.

    Science.gov (United States)

    Mandelblatt, Jeanne; van Ravesteyn, Nicolien; Schechter, Clyde; Chang, Yaojen; Huang, An-Tsun; Near, Aimee M; de Koning, Harry; Jemal, Ahmedin

    2013-07-15

    US breast cancer mortality is declining, but thousands of women still die each year. Two established simulation models examine 6 strategies that include increased screening and/or treatment or elimination of obesity versus continuation of current patterns. The models use common national data on incidence and obesity prevalence, competing causes of death, mammography characteristics, treatment effects, and survival/cure. Parameters are modified based on obesity (defined as BMI  ≥  30 kg/m(2) ). Outcomes are presented for the year 2025 among women aged 25+ and include numbers of cases, deaths, mammograms and false-positives; age-adjusted incidence and mortality; breast cancer mortality reduction and deaths averted; and probability of dying of breast cancer. If current patterns continue, the models project that there would be about 50,100-57,400 (range across models) annual breast cancer deaths in 2025. If 90% of women were screened annually from ages 40 to 54 and biennially from ages 55 to 99 (or death), then 5100-6100 fewer deaths would occur versus current patterns, but incidence, mammograms, and false-positives would increase. If all women received the indicated systemic treatment (with no screening change), then 11,400-14,500 more deaths would be averted versus current patterns, but increased toxicity could occur. If 100% received screening plus indicated therapy, there would be 18,100-20,400 fewer deaths. Eliminating obesity yields 3300-5700 fewer breast cancer deaths versus continuation of current obesity levels. Maximal reductions in breast cancer deaths could be achieved through optimizing treatment use, followed by increasing screening use and obesity prevention. © 2013 American Cancer Society.

  9. When Good Evidence Is Not Enough: The Role of Context in Bowel Cancer Screening Policy in New Zealand

    Science.gov (United States)

    Flitcroft, Kathy L.; Gillespie, James A.; Carter, Stacy M.; Trevena, Lyndal J.; Salkeld, Glenn P.

    2011-01-01

    Bowel cancer is a serious health problem in developed countries. Australia, the United Kingdom (UK) and New Zealand (NZ) reviewed the same randomised controlled trial evidence on the benefits and harms of population-based bowel cancer screening. Yet only NZ, with the highest age standardised rate of bowel cancer mortality, decided against…

  10. The Success of a Policy Model: Irrigation Management Transfer in Mexico

    NARCIS (Netherlands)

    Rap, E.R.

    2006-01-01

    The Mexican policy of Irrigation Management Transfer has been widely propagated as a success and has become a model for other countries seeking to improve the performance of their irrigation systems while also cutting public expenditures. This article analyses the process of policy-making that has

  11. The Rotation and Assignment of Imbalanced Air Force Specialties: A Policy Analysis Model.

    Science.gov (United States)

    1984-07-01

    OCS R = REMO )TE. REQRENM. RIQOS /\\ - _:/ ., --- -- ..70 ~~RI QODL !1 \\ """... . .........................................."- 0 r -~- (0 II ( rI 1 22...Corporate System Model of a Sports Club: Using Simulatiiin as an Aid Policies which alter tour lengths or make minor changes in to Policy Making in a

  12. Partial Atomic Charges and Screened Charge Models of the Electrostatic Potential.

    Science.gov (United States)

    Wang, Bo; Truhlar, Donald G

    2012-06-12

    We propose a new screened charge method for calculating partial atomic charges in molecules by electrostatic potential (ESP) fitting. The model, called full density screening (FDS), is used to approximate the screening effect of full charge densities of atoms in molecules. The results are compared to the conventional ESP fitting method based on point charges and to our previously proposed outer density screening (ODS) method, in which the parameters are reoptimized for the present purpose. In ODS, the charge density of an atom is represented by the sum of a point charge and a smeared negative charge distributed in a Slater-type orbital (STO). In FDS, the charge density of an atom is taken to be the sum of the charge density of the neutral atom and a partial atomic charge (of either sign) distributed in an STO. The ζ values of the STOs used in these two models are optimized in the present study to best reproduce the electrostatic potentials. The quality of the fit to the electrostatics is improved in the screened charge methods, especially for the regions that are within one van der Waals radius of the centers of atoms. It is also found that the charges derived by fitting electrostatic potentials with screened charges are less sensitive to the positions of the fitting points than are those derived with conventional electrostatic fitting. Moreover, we found that the electrostatic-potential-fitted (ESP) charges from the screened charge methods are similar to those from the point-charge method except for molecules containing the methyl group, where we have explored the use of restraints on nonpolar H atoms. We recommend the FDS model if the only goal is ESP fitting to obtain partial atomic charges or a fit to the ESP field. However, the ODS model is more accurate for electronic embedding in combined quantum mechanical and molecular mechanical (QM/MM) modeling and is more accurate than point-charge models for ESP fitting, and it is recommended for applications

  13. Cost savings from a teledentistry model for school dental screening: an Australian health system perspective.

    Science.gov (United States)

    Estai, Mohamed; Bunt, Stuart; Kanagasingam, Yogesan; Tennant, Marc

    2017-06-05

    Objective The aim of the present study was to compare the costs of teledentistry and traditional dental screening approaches in Australian school children. Methods A cost-minimisation analysis was performed from the perspective of the oral health system, comparing the cost of dental screening in school children using a traditional visual examination approach with the cost of mid-level dental practitioners (MLDPs), such as dental therapists, screening the same cohort of children remotely using teledentistry. A model was developed to simulate the costs (over a 12-month period) of the two models of dental screening for all school children (2.7million children) aged 5-14 years across all Australian states and territories. The fixed costs and the variable costs, including staff salary, travel and accommodation costs, and cost of supply were calculated. All costs are given in Australian dollars. Results The total estimated cost of the teledentistry model was $50million. The fixed cost of teledentistry was $1million and that of staff salaries (tele-assistants, charters and their supervisors, as well as information technology support was estimated to be $49million. The estimated staff salary saved with the teledentistry model was $56million, and the estimated travel allowance and supply expenses avoided were $16million and $14million respectively; an annual reduction of $85million in total. Conclusions The present study shows that the teledentistry model of dental screening can minimise costs. The estimated savings were due primarily to the low salaries of dental therapists and the avoidance of travel and accommodation costs. Such savings could be redistributed to improve infrastructure and oral health services in rural or other underserved areas. What is known about the topic? Caries is a preventable disease, which, if it remains untreated, can cause significant morbidity requiring costly treatment. Regular dental screening and oral health education have the great

  14. Interaction between fiscal and monetary policy in a dynamic nonlinear model.

    Science.gov (United States)

    Bertella, Mario A; Rego, Henio A; Neris, Celso; Silva, Jonathas N; Podobnik, Boris; Stanley, H Eugene

    2015-01-01

    The objective of this study is to verify the dynamics between fiscal policy, measured by public debt, and monetary policy, measured by a reaction function of a central bank. Changes in monetary policies due to deviations from their targets always generate fiscal impacts. We examine two policy reaction functions: the first related to inflation targets and the second related to economic growth targets. We find that the condition for stable equilibrium is more restrictive in the first case than in the second. We then apply our simulation model to Brazil and United Kingdom and find that the equilibrium is unstable in the Brazilian case but stable in the UK case.

  15. Inside 'Inside View': reflections on stimulating debate and engagement through a multimedia live theatre production on the dilemmas and issues of pre-natal screening policy and practice.

    Science.gov (United States)

    Hundt, Gillian Lewando; Bryanston, Claudette; Lowe, Pam; Cross, Saul; Sandall, Jane; Spencer, Kevin

    2011-03-01

    The role of applied theatre in engaging both lay and professional publics with debate on health policy and practice is an emergent field. This paper discusses the development, production performance and discussion of 'Inside View'. The objectives were to produce applied theatre from research findings of a completed study on genetic prenatal screening, exploring the dilemmas for women and health professionals of prenatal genetic screening, and to engage audiences in debate and reflection on the dilemmas of prenatal genetic screening. 'Inside View' was developed from a multidisciplinary research study through identification of emergent themes from qualitative interviews, and development of these by the writer, theatre producer and media technologist with input from the researchers. Inside View was performed in London and the Midlands to varied audiences with a panel discussion and evaluation post performance. The audiences were engaged in debate that was relevant to them professionally and personally. Knowledge translation through applied theatre is an effective tool for engaging the public but the impact subsequently is unclear. There are ethical issues of unexpected disclosure during discussion post performance and the process of transforming research findings into applied theatre requires time and trust within the multidisciplinary team as well as adequate resourcing. © 2010 The Authors. Health Expectations © 2010 Blackwell Publishing Ltd.

  16. Modeling of high-frequency wave propagation in the heterogenous Earth using screen method

    Science.gov (United States)

    Ding, Y.; Zheng, Y.

    2017-12-01

    High-frequency (1Hz) wave propagation modeling in the heterogenous Earth is difficult due to computation cost. We have developed one alternative method to do high-frequency wave propagation locally in the Earth. First, we divide the heterogeneous Earth model into two parts: the background gradient velocity model, and the velocity perturbation. Then we trace rays from the source to the Earth surface and make screens perpendicular to the rays. We propagate the wavefield in each screen by Kirchhoff surface integral and account for the velocity perturbations with a phase shift. Recursively, the algorithm will propagate the wavefield locally from the source to the surface. The result is compared with that from the finite difference method.

  17. CHAM: a fast algorithm of modelling non-linear matter power spectrum in the sCreened HAlo Model

    Science.gov (United States)

    Hu, Bin; Liu, Xue-Wen; Cai, Rong-Gen

    2018-02-01

    We present a fast numerical screened halo model algorithm (CHAM) for modeling non-linear power spectrum for the alternative models to ΛCDM. This method has three obvious advantages. First of all, it is not being restricted to a specific dark energy/modified gravity model. In principle, all of the screened scalar-tensor theories can be applied. Second, the least assumptions are made in the calculation. Hence, the physical picture is very easily understandable. Third, it is very predictable and does not rely on the calibration from N-body simulation. As an example, we show the case of Hu-Sawicki f(R) gravity. In this case, the typical CPU time with the current parallel Python script (8 threads) is roughly within 10 minutes. The resulting spectra are in a good agreement with N-body data within a few percentage accuracy up to k ˜ 1 h/Mpc.

  18. THREE MODELS OF NATIONAL CRIMINAL POLICY IN THE CONTEXT OF GLOBALIZATION

    Directory of Open Access Journals (Sweden)

    Ivan Kleymenov

    2017-01-01

    Full Text Available The author identifies three models of national criminal policy: the sovereign, reformist and experimental. The main criteria of such differentiation are the exposure to global influence, the criminological soundness and stability of criminal policy. Identification of the model of criminal policy in a particular state is a complex task that requires independent research.The subject. The article is devoted to modeling of the national criminal policy in modern conditions of globalization. The article discusses various models of criminal policy in the conditions of globalization.The purpose of the author is to describe the basic models of national criminal policy in modern conditions of globalization.The methodology. The author uses the method of analysis and synthesis, formal legal method as well as sociological methods (survey.The results, scope of application. The author identifies three models of national criminal policy: the sovereign, reformist and experimental. The main criteria of such differentiation are the exposure to global influence, the criminological soundness and stability of criminal policy. The sovereign model is based on doctrine of weak state and a strong combat criminal activity. It is distinguished by the pursuit of the realization of the equality of all before the law, criminal strategic and political planning system with a clear definition of goals and objectives; criminological security. The reform of criminal policy is characterized byuncertainty goals and objectives, utopianism and pretentiousness, dependence on standards of the international organization, the lower prestige of criminology, reduction of social programs, lobbying of group interests, permanent amendments to the criminal and criminal procedure legislation. Experimental model of criminal policy is connected with approbation of such technologies of management of society that are criminal and contrary to human experience in fighting crime.Conclusions. Criminal

  19. High-Throughput Screening and Prediction Model Building for Novel Hemozoin Inhibitors Using Physicochemical Properties.

    Science.gov (United States)

    Huy, Nguyen Tien; Chi, Pham Lan; Nagai, Jun; Dang, Tran Ngoc; Mbanefo, Evaristus Chibunna; Ahmed, Ali Mahmoud; Long, Nguyen Phuoc; Thoa, Le Thi Bich; Hung, Le Phi; Titouna, Afaf; Kamei, Kaeko; Ueda, Hiroshi; Hirayama, Kenji

    2017-02-01

    It is essential to continue the search for novel antimalarial drugs due to the current spread of resistance against artemisinin by Plasmodium falciparum parasites. In this study, we developed in silico models to predict hemozoin inhibitors as a potential first-step screening for novel antimalarials. An in vitro colorimetric high-throughput screening assay of hemozoin formation was used to identify hemozoin inhibitors from 9,600 structurally diverse compounds. The physicochemical properties of positive hits and randomly selected compounds were extracted from the ChemSpider database; they were used for developing prediction models to predict hemozoin inhibitors using two different approaches, i.e., traditional multivariate logistic regression and Bayesian model averaging. Our results showed that a total of 224 positive-hit compounds exhibited the ability to inhibit hemozoin formation, with 50% inhibitory concentrations (IC 50 s) ranging from 3.1 μM to 199.5 μM. The best model according to traditional multivariate logistic regression included the three variables octanol-water partition coefficient, number of hydrogen bond donors, and number of atoms of hydrogen, while the best model according to Bayesian model averaging included the three variables octanol-water partition coefficient, number of hydrogen bond donors, and index of refraction. Both models had a good discriminatory power, with area under the curve values of 0.736 and 0.781 for the traditional multivariate model and Bayesian model averaging, respectively. In conclusion, the prediction models can be a new, useful, and cost-effective approach for the first screen of hemozoin inhibition-based antimalarial drug discovery. Copyright © 2017 American Society for Microbiology.

  20. Cultural Explanations of Electoral Reform: A Policy Cycle Model

    OpenAIRE

    Norris, Pippa

    2010-01-01

    The standard explanation of electoral reform is offered by rational choice accounts. These regard the choice of rules as an elite-level issue, dominated by partisan interests bargaining within the legislature, where citizens are usually marginalized and powerless. Such accounts may help to explain what specific reforms are enacted but they lack the capacity to account satisfactorily for the logically prior questions: when and why are any successful reforms raised on the policy agenda? Part I ...

  1. Consignment Stock Inventory Policy: Methodological Framework and Model

    OpenAIRE

    Battini, Daria; Grassi, Andrea; Persona, Alessandro; Sgarbossa, Fabio

    2010-01-01

    Abstract Consignment Stock (CS) is an innovative approach to supply and stock management, based on a strong and continuous collaboration between vendor and buyer to create a ?win-win? situation, where both partners have equal gains. An analytic formulation of CS policy with obsolescence has been proposed in Persona et al. (2005). This article considers new critical factors (present in several industrial environments) providing a logical extension of the above mentioned study. T...

  2. Assessing Stop-Loss Policy Options through Personnel Flow Modeling

    Science.gov (United States)

    2014-01-01

    respond to iso - lated policy changes for stop-loss in a manner fundamentally similar to any alternative system change that, too, would have to reconcile...All Units - Scale: 5 Pct of Force FY07 Accession Pattern 0 5000 10000 15000 20000 25000 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Year

  3. Macroprudential Policy in a Fisherian Model of Financial Innovation

    OpenAIRE

    Javier Bianchi; Emine Boz; Enrique Gabriel Mendoza

    2012-01-01

    The interaction between credit frictions, financial innovation, and a switch from optimistic to pessimistic beliefs played a central role in the 2008 financial crisis. This paper develops a quantitative general equilibrium framework in which this interaction drives the financial amplification mechanism to study the effects of macroprudential policy. Financial innovation enhances the ability of agents to collateralize assets into debt, but the riskiness of this new regime can only be learned o...

  4. Strategic environmental assessment policy integration model for solid waste management in Malaysia

    International Nuclear Information System (INIS)

    Victor, Dennis; Agamuthu, P.

    2013-01-01

    Highlights: • We identified policy drivers of SEA in solid waste policy planning. • The SEA primary policy drivers are benefits, barriers and enablers need. • The SEA sub-drivers are environmental attitude and environmental awareness. • Optimal SEA policy integration requires public participation and capacity building. • SEA integration should be a long-term sustainable policy strategy for SWM. -- Abstract: This paper examines the strategic environmental assessment (SEA) systemic policy drivers for solid waste management (SWM) policies, plans and programmes (PPP) in Malaysia. Solid waste generation in Malaysia has been increasing drastically from 9.0 million tonnes in 2000 to an expected 15.6 million tonnes in 2020. This projected rate of solid waste generation is expected to burden the country's environmental and water quality resources. The key problem the study frames is the lack of environmental integration in the SWM process which is only conducted during the environmental impact assessments (EIA) stage of SWM facilities. The purpose of this study is to expand the SEA subject knowledge by validating a behaviour based theoretical framework and identifying key policy drivers that influence the integration of SEA in SWM policy planning. The study methodology utilized a confirmatory covariance based structural equation modelling approach to validate the proposed theoretical model based on the policy makers/implementers interview questionnaire data collection. The study findings indicate five latent SEA policy drivers which were named policy knowledge, environmental attitude, perceived benefits, perceived barriers and perceived enablers. The study has conceptualized and tested a SEA policy model which indicates that SEA integration behaviour is influenced directly by three main drivers (perception of benefits, perception of barriers and perception of enablers) and influenced indirectly by two sub-drivers environmental attitude and environmental knowledge

  5. Screening, Brief Intervention and Referral to Treatment: implications of SAMHSA's SBIRT initiative for substance abuse policy and practice.

    Science.gov (United States)

    Babor, Thomas F; Del Boca, Frances; Bray, Jeremy W

    2017-02-01

    This paper describes the major findings and public health implications of a cross-site evaluation of a national Screening, Brief Intervention and Referral to Treatment (SBIRT) demonstration program funded by the US Substance Abuse and Mental Health Services Administration (SAMHSA). Eleven multi-site programs in two cohorts of SAMHSA grant recipients were each funded for 5 years to promote the adoption and sustained implementation of SBIRT. The SBIRT cross-site evaluation used a multi-method evaluation design to provide comprehensive information on the processes, outcomes and costs of SBIRT as implemented in a variety of medical and community settings. SBIRT programs in the two evaluated SAMHSA cohorts screened more than 1 million patients/clients. SBIRT implementation was facilitated by committed leadership and the use of substance use specialists, rather than medical generalists, to deliver services. Although the quasi-experimental nature of the outcome evaluation does not permit causal inferences, pre-post differences were clinically meaningful and statistically significant for almost every measure of substance use. Greater intervention intensity was associated with larger decreases in substance use. Both brief intervention and brief treatment were associated with positive outcomes, but brief intervention was more cost-effective for most substances. Sixty-nine (67%) of the original performance sites adapted and redesigned SBIRT service delivery after initial grant funding ended. Four factors influenced SBIRT sustainability: presence of program champions, availability of funding, systemic change and effective management of SBIRT provider challenges. The US Substance Abuse and Mental Health Services Administration's Screening, Brief Intervention and Referral to Treatment (SBIRT) demonstration program was adapted successfully to the needs of early identification efforts for hazardous use of alcohol and illicit drugs. SBIRT is an innovative way to integrate the

  6. LOCAL INDEPENDENCE FEATURE SCREENING FOR NONPARAMETRIC AND SEMIPARAMETRIC MODELS BY MARGINAL EMPIRICAL LIKELIHOOD

    Science.gov (United States)

    Chang, Jinyuan; Tang, Cheng Yong; Wu, Yichao

    2015-01-01

    We consider an independence feature screening technique for identifying explanatory variables that locally contribute to the response variable in high-dimensional regression analysis. Without requiring a specific parametric form of the underlying data model, our approach accommodates a wide spectrum of nonparametric and semiparametric model families. To detect the local contributions of explanatory variables, our approach constructs empirical likelihood locally in conjunction with marginal nonparametric regressions. Since our approach actually requires no estimation, it is advantageous in scenarios such as the single-index models where even specification and identification of a marginal model is an issue. By automatically incorporating the level of variation of the nonparametric regression and directly assessing the strength of data evidence supporting local contribution from each explanatory variable, our approach provides a unique perspective for solving feature screening problems. Theoretical analysis shows that our approach can handle data dimensionality growing exponentially with the sample size. With extensive theoretical illustrations and numerical examples, we show that the local independence screening approach performs promisingly. PMID:27242388

  7. PBT assessment and prioritization by PBT Index and consensus modeling: comparison of screening results from structural models.

    Science.gov (United States)

    Gramatica, Paola; Cassani, Stefano; Sangion, Alessandro

    2015-04-01

    The limited availability of comprehensive data for Persistence, Bioaccumulation and Toxicity (PBT) of chemicals is a serious hindrance to the assignment of compounds to the categories of PBT and vPvB; REACH regulation requires authorization for the use of such chemicals, and additionally plans for safer alternatives. In the context of screening and priority-setting tools for PBT-assessment, the cumulative PBT Index model, implemented in QSARINS (QSAR-INSUBRIA), new software tool for the development and validation of multiple linear regression QSAR models, offers a new holistic approach for the identification of chemicals with cumulative PBT properties directly from their molecular structure. In this study the Insubria PBT Index in QSARINS is applied to the screening and prioritization of various data sets, containing a large variety of chemicals of heterogeneous molecular structure, previously screened by various authors by different methods, for their potential PBT behavior. Particular attention is devoted to the model Applicability Domain, using different approaches such as Descriptor Range, Leverage, and Principal Component Analysis (PCA) of the modeling molecular descriptors, in order to discriminate between interpolated and extrapolated predictions. The results of this screening, which is based only on the molecular structure features and is not dependent on single threshold values for P, B and T, are compared with those obtained by the on-line US-EPA PBT Profiler. Good agreement between the various approaches is found, supporting the utility of a consensus approach in priority-setting studies. The main discrepancies are highlighted and commented on. Moreover, a priority list containing the most hazardous compounds identified in agreement between the two tools is drafted. The PBT Index, implemented in QSARINS, which was demonstrated to be a practical, precautionary and reliable screening tool for PBT-behavior directly from the molecular structure, can be

  8. Comparative analysis of 5 lung cancer natural history and screening models that reproduce outcomes of the NLST and PLCO trials.

    Science.gov (United States)

    Meza, Rafael; ten Haaf, Kevin; Kong, Chung Yin; Erdogan, Ayca; Black, William C; Tammemagi, Martin C; Choi, Sung Eun; Jeon, Jihyoun; Han, Summer S; Munshi, Vidit; van Rosmalen, Joost; Pinsky, Paul; McMahon, Pamela M; de Koning, Harry J; Feuer, Eric J; Hazelton, William D; Plevritis, Sylvia K

    2014-06-01

    The National Lung Screening Trial (NLST) demonstrated that low-dose computed tomography screening is an effective way of reducing lung cancer (LC) mortality. However, optimal screening strategies have not been determined to date and it is uncertain whether lighter smokers than those examined in the NLST may also benefit from screening. To address these questions, it is necessary to first develop LC natural history models that can reproduce NLST outcomes and simulate screening programs at the population level. Five independent LC screening models were developed using common inputs and calibration targets derived from the NLST and the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial (PLCO). Imputation of missing information regarding smoking, histology, and stage of disease for a small percentage of individuals and diagnosed LCs in both trials was performed. Models were calibrated to LC incidence, mortality, or both outcomes simultaneously. Initially, all models were calibrated to the NLST and validated against PLCO. Models were found to validate well against individuals in PLCO who would have been eligible for the NLST. However, all models required further calibration to PLCO to adequately capture LC outcomes in PLCO never-smokers and light smokers. Final versions of all models produced incidence and mortality outcomes in the presence and absence of screening that were consistent with both trials. The authors developed 5 distinct LC screening simulation models based on the evidence in the NLST and PLCO. The results of their analyses demonstrated that the NLST and PLCO have produced consistent results. The resulting models can be important tools to generate additional evidence to determine the effectiveness of lung cancer screening strategies using low-dose computed tomography. © 2014 American Cancer Society.

  9. Screening for gestational diabetes mellitus by a model based on risk indicators

    DEFF Research Database (Denmark)

    Jensen, Dorte Møller; Mølsted-Pedersen, Lars; Beck-Nielsen, Henning

    2003-01-01

    OBJECTIVE: This study was performed to prospectively evaluate a screening model for gestational diabetes mellitus on the basis of clinical risk indicators. STUDY DESIGN: In a prospective multicenter study with 5235 consecutive pregnant women, diagnostic testing with a 2-hour 75-g oral glucose...... of the results from tested women to the whole group in question, a 2.4% prevalence of gestational diabetes mellitus was calculated. Sensitivity and specificity of the model was 80.6 (73.7-87.6) and 64.8 (63.5-66.1), respectively (95% CIs). CONCLUSION: Under ideal conditions, sensitivity of the model...

  10. Examining Policies to Reduce Homelessness Using a General Equilibrium Model of the Housing Market

    OpenAIRE

    Mansur, Erin; Quigley, John M.; Raphael, Steven; Smolensky, Eugene

    2003-01-01

    In this paper, we use a general equilibrium simulation model to assess the potential impacts on homelessness of various housing-market policy interventions. We calibrate the model to the four largest metropolitan areas in California. We explore the welfare con- sequences and the effects on homelessness of three housing-market policy interventions: extending housing vouchers to all low-income households, subsidizing all landlords, and subsidizing those landlords who supply low-income housing. ...

  11. Impact of template choice on homology model efficiency in virtual screening.

    Science.gov (United States)

    Rataj, Krzysztof; Witek, Jagna; Mordalski, Stefan; Kosciolek, Tomasz; Bojarski, Andrzej J

    2014-06-23

    Homology modeling is a reliable method of predicting the three-dimensional structures of proteins that lack NMR or X-ray crystallographic data. It employs the assumption that a structural resemblance exists between closely related proteins. Despite the availability of many crystal structures of possible templates, only the closest ones are chosen for homology modeling purposes. To validate the aforementioned approach, we performed homology modeling of four serotonin receptors (5-HT1AR, 5-HT2AR, 5-HT6R, 5-HT7R) for virtual screening purposes, using 10 available G-Protein Coupled Receptors (GPCR) templates with diverse evolutionary distances to the targets, with various approaches to alignment construction and model building. The resulting models were further validated in two steps by means of ligand docking and enrichment calculation, using Glide software. The final quality of the models was determined in virtual screening-like experiments by the AUROC score of the resulting ROC curves. The outcome of this research showed that no correlation between sequence identity and model quality was found, leading to the conclusion that the closest phylogenetic relative is not always the best template for homology modeling.

  12. An Affinity-to-Commons Model of Public Support For Environmental Energy Policy

    International Nuclear Information System (INIS)

    Merrill, Ryan; Sintov, Nicole

    2016-01-01

    As atmospheric CO 2 continues to rise above 450 PPM, policymakers struggle with uncertainty concerning predictors of citizen support for environmental energy policies (EEPs) and preferences for their design, topics which have received limited attention in empirical literature. We present an original model of policy support based on citizens’ affinity-to-commons: pathways by which individuals enjoy natural public goods that in turn shape preferences between alternative policy mechanisms. We evaluate this model using a survey of southern California electricity customers, with results indicating the model's utility in predicting public support of EEP. Stronger community ties are associated with preferences for “pull”-type subsidies, whereas stronger connections to natural commons are linked to support for both “pull” and “push”-type sanctions. Findings have implications for coalition building as advocates may engender support for green energy policy by framing sanctions as protecting natural commons, and framing subsidies either in this same way and/or as producing benefits for communities. - Highlights: • A commons-oriented model of citizen support for environmental energy policy is proposed (Thaler (2012)). • A factor analysis identifies local tax shifts, green subsidies, and energy taxes (Schultz et al. (1995)). • Community connections predict support for policies with employing subsidies (Sabatier (2006)). • Connection to nature predicts support for policies using both sanctions and subsidies. (Stern et al. (1999)).

  13. Parameter uncertainty in CGE Modeling of the environmental impacts of economic policies

    Energy Technology Data Exchange (ETDEWEB)

    Abler, D.G.; Shortle, J.S. [Agricultural Economics, Pennsylvania State University, University Park, PA (United States); Rodriguez, A.G. [University of Costa Rica, San Jose (Costa Rica)

    1999-07-01

    This study explores the role of parameter uncertainty in Computable General Equilibrium (CGE) modeling of the environmental impacts of macroeconomic and sectoral policies, using Costa Rica as a case for study. A CGE model is constructed which includes eight environmental indicators covering deforestation, pesticides, overfishing, hazardous wastes, inorganic wastes, organic wastes, greenhouse gases, and air pollution. The parameters are treated as random variables drawn from prespecified distributions. Evaluation of each policy option consists of a Monte Carlo experiment. The impacts of the policy options on the environmental indicators are relatively robust to different parameter values, in spite of the wide range of parameter values employed. 33 refs.

  14. Parameter uncertainty in CGE Modeling of the environmental impacts of economic policies

    International Nuclear Information System (INIS)

    Abler, D.G.; Shortle, J.S.; Rodriguez, A.G.

    1999-01-01

    This study explores the role of parameter uncertainty in Computable General Equilibrium (CGE) modeling of the environmental impacts of macroeconomic and sectoral policies, using Costa Rica as a case for study. A CGE model is constructed which includes eight environmental indicators covering deforestation, pesticides, overfishing, hazardous wastes, inorganic wastes, organic wastes, greenhouse gases, and air pollution. The parameters are treated as random variables drawn from prespecified distributions. Evaluation of each policy option consists of a Monte Carlo experiment. The impacts of the policy options on the environmental indicators are relatively robust to different parameter values, in spite of the wide range of parameter values employed. 33 refs

  15. Measurement and Monte Carlo modeling of the spatial response of scintillation screens

    Energy Technology Data Exchange (ETDEWEB)

    Pistrui-Maximean, S.A. [CNDRI (NDT using Ionizing Radiation) Laboratory, INSA-Lyon, 69621 Villeurbanne (France)], E-mail: spistrui@gmail.com; Letang, J.M. [CNDRI (NDT using Ionizing Radiation) Laboratory, INSA-Lyon, 69621 Villeurbanne (France)], E-mail: jean-michel.letang@insa-lyon.fr; Freud, N. [CNDRI (NDT using Ionizing Radiation) Laboratory, INSA-Lyon, 69621 Villeurbanne (France); Koch, A. [Thales Electron Devices, 38430 Moirans (France); Walenta, A.H. [Detectors and Electronics Department, FB Physik, Siegen University, 57068 Siegen (Germany); Montarou, G. [Corpuscular Physics Laboratory, Blaise Pascal University, 63177 Aubiere (France); Babot, D. [CNDRI (NDT using Ionizing Radiation) Laboratory, INSA-Lyon, 69621 Villeurbanne (France)

    2007-11-01

    In this article, we propose a detailed protocol to carry out measurements of the spatial response of scintillation screens and to assess the agreement with simulated results. The experimental measurements have been carried out using a practical implementation of the slit method. A Monte Carlo simulation model of scintillator screens, implemented with the toolkit Geant4, has been used to study the influence of the acquisition setup parameters and to compare with the experimental results. An algorithm of global stochastic optimization based on a localized random search method has been implemented to adjust the optical parameters (optical scattering and absorption coefficients). The algorithm has been tested for different X-ray tube voltages (40, 70 and 100 kV). A satisfactory convergence between the results simulated with the optimized model and the experimental measurements is obtained.

  16. Virtual Screening Models for Prediction of HIV-1 RT Associated RNase H Inhibition

    DEFF Research Database (Denmark)

    Poongavanam, Vasanthanathan; Kongsted, Jacob

    2013-01-01

    of choice in terms of best retrieval of active from inactive compounds and efficiency and efficacy schemes. Moreover, shape similarity, machine learning and FLAP models could also be used for further validation or filtration in virtual screening processes. The best models could potentially be use...... reverse transcriptase associated ribonuclease H (RNase H) function provides a novel target for anti-HIV chemotherapy. Here we report on the applicability of conceptually different in silico approaches as virtual screening (VS) tools in order to efficiently identify RNase H inhibitors from large chemical...... databases. The methods used here include machine-learning algorithms (e.g. support vector machine, random forest and kappa nearest neighbor), shape similarity (rapid overlay of chemical structures), pharmacophore, molecular interaction fields-based fingerprints for ligands and protein (FLAP) and flexible...

  17. Legislative and Policy Developments and Imperatives for Advancing the Primary Care Behavioral Health (PCBH) Model.

    Science.gov (United States)

    Freeman, Dennis S; Hudgins, Cathy; Hornberger, Joel

    2018-03-05

    The Primary Care Behavioral Health (PCBH) practice model continues to gain converts among primary care and behavioral health professionals as the evidence supporting its effectiveness continues to accumulate. Despite a growing number of practices and organizations using the model effectively, widespread implementation has been hampered by outmoded policies and regulatory barriers. As policymakers and legislators begin to recognize the contributions that PCBH model services make to the care of complex patients and the expansion of access to those in need of behavioral health interventions, some encouraging policy initiatives are emerging and the policy environment is becoming more favorable to implementation of the PCBH model. This article outlines the necessity for policy change, exposing the policy issues and barriers that serve to limit the practice of the PCBH model; highlights innovative approaches some states are taking to foster integrated practice; and discusses the compatibility of the PCBH model with the nation's health care reform agenda. Psychologists have emerged as leaders in the design and implementation of PCBH model integration and are encouraged to continue to advance the model through the demonstration of efficient and effective clinical practice, participation in the expansion of an appropriately trained workforce, and advocacy for the inclusion of this practice model in emerging healthcare systems and value-based payment methodologies.

  18. Diagnostic performance and costs of contingent screening models for trisomy 21 incorporating non-invasive prenatal testing.

    Science.gov (United States)

    Maxwell, Susannah; O'Leary, Peter; Dickinson, Jan E; Suthers, Graeme K

    2017-08-01

    Contingent screening for trisomy 21 using non-invasive prenatal testing has the potential to reduce invasive diagnostic testing and increase the detection of trisomy 21. To describe the diagnostic and economic performance of prenatal screening models for trisomy 21 that use non-invasive prenatal testing as a contingent screen across a range of combined first trimester screening risk cut-offs from a public health system perspective. Using a hypothetical cohort of 300 000 pregnancies, we modelled the outcomes of 25 contingent non-invasive prenatal testing screening models and compared these to conventional screening, offering women with a high-risk (1 > 300) combined first trimester screening result an invasive test. The 25 models used a range of risk cut-offs. High-risk women were offered invasive testing. Intermediate-risk women were offered non-invasive prenatal testing. We report the cost of each model, detection rate, costs per diagnosis, invasive tests per diagnosis and the number of fetal losses per diagnosis. The cost per prenatal diagnosis of trisomy 21 using the conventional model was $51 876 compared to the contingent models which varied from $49 309-66 686. The number of diagnoses and cost per diagnosis increased as the intermediate-risk threshold was lowered. Results were sensitive to trisomy 21 incidence, uptake of testing and cost of non-invasive prenatal testing. Contingent non-invasive prenatal testing models using more sensitive combined first trimester screening risk cut-offs than conventional screening improved the detection rate of trisomy 21, reduced procedure-related fetal loss and could potentially be provided at a lower cost per diagnosis than conventional screening. © 2017 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

  19. Screening of Industrial Development Policies, Plans and Programs of Strategic Environmental Assessment in the Industrial Sector of Iran

    OpenAIRE

    J. Nouri; B. Maghsoudlou Kamali

    2005-01-01

    The present investigation deals with the quality of capacity building and institutional strengthening of Strategic Environmental Assessment (SEA) in the industrial sector as well as determining the environmental strategies for industrial sustainable development in Iran. The leading aim of this paper has been to systematize the environmental considerations in industrial development strategies, policies, plans and programs in the highest strategic decision making processes and to ensure environ...

  20. Homology model-based virtual screening for GPCR ligands using docking and target-biased scoring.

    Science.gov (United States)

    Radestock, Sebastian; Weil, Tanja; Renner, Steffen

    2008-05-01

    The current study investigates the combination of two recently reported techniques for the improvement of homology model-based virtual screening for G-protein coupled receptor (GPCR) ligands. First, ligand-supported homology modeling was used to generate receptor models that were in agreement with mutagenesis data and structure-activity relationship information of the ligands. Second, interaction patterns from known ligands to the receptor were applied for scoring and rank ordering compounds from a virtual library using ligand-receptor interaction fingerprint-based similarity (IFS). Our approach was evaluated in retrospective virtual screening experiments for antagonists of the metabotropic glutamate receptor (mGluR) subtype 5. The results of our approach were compared to the results obtained by conventional scoring functions (Dock-Score, PMF-Score, Gold-Score, ChemScore, and FlexX-Score). The IFS lead to significantly higher enrichment rates, relative to the competing scoring functions. Though using a target-biased scoring approach, the results were not biased toward the chemical classes of the reference structures. Our results indicate that the presented approach has the potential to serve as a general setup for successful structure-based GPCR virtual screening.

  1. Health Beliefs and Breast Cancer Screening in Rural Appalachia: An Evaluation of the Health Belief Model.

    Science.gov (United States)

    VanDyke, Santana D; Shell, Madelynn D

    2017-09-01

    This study explored the role of the Health Belief Model in predicting breast cancer screening among women in rural Appalachia. Health beliefs (perceived susceptibility to breast cancer, severity of breast cancer, and benefits and barriers to screening) were used to predict health behavior (mammogram frequency). A total of 170 women aged 18-78 were recruited at a free health clinic in central Appalachia. Women completed surveys that assessed demographic characteristics, mammogram frequency, and perceived susceptibility, severity, and benefits and barriers to mammography. Consistent with expectations, women with objectively elevated risks for breast cancer (history of abnormal mammograms or family history of breast cancer) perceived themselves to be at higher risk for breast cancer, and those with a history of abnormal mammograms were more likely to receive mammograms regularly. In addition, older women expected their prognosis to be marginally poorer following a diagnosis, perceived greater benefits and fewer barriers to mammography, and were significantly more likely to receive mammograms regularly. Consistent with the Health Belief Model, fewer perceived barriers to mammography predicted greater mammogram frequency. However, the model was not fully supported because perceived susceptibility, severity, and benefits to mammography did not predict mammogram frequency. Results highlight the importance of reducing real and perceived barriers to screening in order to improve mammography rates among rural populations. © 2016 National Rural Health Association.

  2. Evaluation of Cannabidiol in Animal Seizure Models by the Epilepsy Therapy Screening Program (ETSP).

    Science.gov (United States)

    Klein, Brian D; Jacobson, Catherine A; Metcalf, Cameron S; Smith, Misty D; Wilcox, Karen S; Hampson, Aidan J; Kehne, John H

    2017-07-01

    Cannabidiol (CBD) is a cannabinoid component of marijuana that has no significant activity at cannabinoid receptors or psychoactive effects. There is considerable interest in CBD as a therapy for epilepsy. Almost a third of epilepsy patients are not adequately controlled by clinically available anti-seizure drugs (ASDs). Initial studies appear to demonstrate that CBD preparations may be a useful treatment for pharmacoresistant epilepsy. The National Institute of Neurological Disorders and Stroke (NINDS) funded Epilepsy Therapy Screening Program (ETSP) investigated CBD in a battery of seizure models using a refocused screening protocol aimed at identifying pharmacotherapies to address the unmet need in pharmacoresistant epilepsy. Applying this new screening workflow, CBD was investigated in mouse 6 Hz 44 mA, maximal electroshock (MES), corneal kindling models and rat MES and lamotrigine-resistant amygdala kindling models. Following intraperitoneal (i.p.) pretreatment, CBD produced dose-dependent protection in the acute seizure models; mouse 6 Hz 44 mA (ED 50 164 mg/kg), mouse MES (ED 50 83.5 mg/kg) and rat MES (ED 50 88.9 mg/kg). In chronic models, CBD produced dose-dependent protection in the corneal kindled mouse (ED 50 119 mg/kg) but CBD (up to 300 mg/kg) was not protective in the lamotrigine-resistant amygdala kindled rat. Motor impairment assessed in conjunction with the acute seizure models showed that CBD exerted seizure protection at non-impairing doses. The ETSP investigation demonstrates that CBD exhibits anti-seizure properties in acute seizure models and the corneal kindled mouse. However, further preclinical and clinical studies are needed to determine the potential for CBD to address the unmet needs in pharmacoresistant epilepsy.

  3. Factors affecting breast cancer screening behavior in Japan--assessment using the health belief model and conjoint analysis.

    Science.gov (United States)

    Tsunematsu, Miwako; Kawasaki, Hiromi; Masuoka, Yuko; Kakehashi, Masayuki

    2013-01-01

    Japanese women in their 40s or older have been encouraged to attend breast cancer screening. However, the breast cancer screening rate in Japan is not as high as in Europe and the United States. The aim of this study was to identify psychological and personal characteristics of women concerning their participation in breast cancer screening using the Health Belief Model (HBM). In addition, the attributes of screening more easily accepted by participants were analyzed by conjoint analysis. In this cross sectional study of 3,200 age 20-69 women, data were collected by an anonymous questionnaire. Questions were based on HBM and personal characteristics, and included attitudes on hypothetical screening attributes. Data of women aged 40-69 were analyzed by logistic regression and conjoint analysis to clarify the factors affecting their participation in breast cancer screening. Among responses collected from 1,280 women of age 20-69, the replies of 993 women of age 40-69 were used in the analysis. Regarding the psychological characteristics based on HBM, the odds ratios were significantly higher in "importance of cancer screening" (95%CI: 1.21-2.47) and "benefits of cancer screening" (95%CI: 1.09-2.49), whereas the odds ratio was significantly lower in "barriers to participation before cancer screening" (95%CI: 0.27-0.51). Conjoint analysis revealed that the respondents, overall, preferred screening to be low cost and by female staff members. Furthermore, it was also clarified that attributes of screening dominant in decision-making were influenced by the employment status and the type of medical insurance of the women. In order to increase participation in breast cancer screening, it is necessary to disseminate accurate knowledge on cancer screening and to reduce barriers to participation. In addition, the attributes of screening more easily accepted were inexpensive, provided by female staff, executed in a hospital and finished in a short time.

  4. IMPACT: a generic tool for modelling and simulating public health policy.

    Science.gov (United States)

    Ainsworth, J D; Carruthers, E; Couch, P; Green, N; O'Flaherty, M; Sperrin, M; Williams, R; Asghar, Z; Capewell, S; Buchan, I E

    2011-01-01

    Populations are under-served by local health policies and management of resources. This partly reflects a lack of realistically complex models to enable appraisal of a wide range of potential options. Rising computing power coupled with advances in machine learning and healthcare information now enables such models to be constructed and executed. However, such models are not generally accessible to public health practitioners who often lack the requisite technical knowledge or skills. To design and develop a system for creating, executing and analysing the results of simulated public health and healthcare policy interventions, in ways that are accessible and usable by modellers and policy-makers. The system requirements were captured and analysed in parallel with the statistical method development for the simulation engine. From the resulting software requirement specification the system architecture was designed, implemented and tested. A model for Coronary Heart Disease (CHD) was created and validated against empirical data. The system was successfully used to create and validate the CHD model. The initial validation results show concordance between the simulation results and the empirical data. We have demonstrated the ability to connect health policy-modellers and policy-makers in a unified system, thereby making population health models easier to share, maintain, reuse and deploy.

  5. Computational and Statistical Models: A Comparison for Policy Modeling of Childhood Obesity

    Science.gov (United States)

    Mabry, Patricia L.; Hammond, Ross; Ip, Edward Hak-Sing; Huang, Terry T.-K.

    As systems science methodologies have begun to emerge as a set of innovative approaches to address complex problems in behavioral, social science, and public health research, some apparent conflicts with traditional statistical methodologies for public health have arisen. Computational modeling is an approach set in context that integrates diverse sources of data to test the plausibility of working hypotheses and to elicit novel ones. Statistical models are reductionist approaches geared towards proving the null hypothesis. While these two approaches may seem contrary to each other, we propose that they are in fact complementary and can be used jointly to advance solutions to complex problems. Outputs from statistical models can be fed into computational models, and outputs from computational models can lead to further empirical data collection and statistical models. Together, this presents an iterative process that refines the models and contributes to a greater understanding of the problem and its potential solutions. The purpose of this panel is to foster communication and understanding between statistical and computational modelers. Our goal is to shed light on the differences between the approaches and convey what kinds of research inquiries each one is best for addressing and how they can serve complementary (and synergistic) roles in the research process, to mutual benefit. For each approach the panel will cover the relevant "assumptions" and how the differences in what is assumed can foster misunderstandings. The interpretations of the results from each approach will be compared and contrasted and the limitations for each approach will be delineated. We will use illustrative examples from CompMod, the Comparative Modeling Network for Childhood Obesity Policy. The panel will also incorporate interactive discussions with the audience on the issues raised here.

  6. Economic modeling and energy policy planning. [technology transfer, market research

    Science.gov (United States)

    Thompson, R. G.; Schwartz, A., Jr.; Lievano, R. J.; Stone, J. C.

    1974-01-01

    A structural economic model is presented for estimating the demand functions for natural gas and crude oil in industry and in steam electric power generation. Extensions of the model to other commodities are indicated.

  7. The Impact of State Legislation and Model Policies on Bullying in Schools.

    Science.gov (United States)

    Terry, Amanda

    2018-04-01

    The purpose of this study was to determine the impact of the coverage of state legislation and the expansiveness ratings of state model policies on the state-level prevalence of bullying in schools. The state-level prevalence of bullying in schools was based on cross-sectional data from the 2013 High School Youth Risk Behavior Survey. Multiple regression was conducted to determine whether the coverage of state legislation and the expansiveness rating of a state model policy affected the state-level prevalence of bullying in schools. The purpose and definition category of components in state legislation and the expansiveness rating of a state model policy were statistically significant predictors of the state-level prevalence of bullying in schools. The other 3 categories of components in state legislation-District Policy Development and Review, District Policy Components, and Additional Components-were not statistically significant predictors in the model. Extensive coverage in the purpose and definition category of components in state legislation and a high expansiveness rating of a state model policy may be important in efforts to reduce bullying in schools. Improving these areas may reduce the state-level prevalence of bullying in schools. © 2018, American School Health Association.

  8. Risk modeling and screening for BRCA1 mutations among Filipino breast cancer patients

    International Nuclear Information System (INIS)

    Nato, Alejandro Q. Jr.

    2003-03-01

    Breast cancer susceptibility gene, type 1(BRCA1) has been thought to be responsible for ∼45% of families with multiple breast carcinomas and for ∼80% of breast and ovarian cancer families. In this study, we investigated 34 familial Filipino breast cancer (BC) patients to: (a) estimate breast cancer risks and BRCA1/2 mutation carrier probabilities using risk assessment and prior probability models, respectively; (b) screen for putative polymorphisms at selected smaller exons of BRCA1 by single-strand conformation polymorphism (SSCP) analysis; (c) screen for truncated mutations at BRCA1 exon 11 by radioactive protein truncation test (PTT); and (d) estimate posterior probabilities upon incorporation of screening results. SSCP analysis revealed 8 unique putative polymorphisms. Low prevalence of unique putative polymorphisms at exon 2, 5, 17, and 22 may indicate probable mutations. Contrastingly, high prevalence of unique putative polymorphisms at exons 13, 15, and 16 may suggest true polymorphisms which are biologically insignificant. PTT, DHPLC, and sequence analyses revealed a novel mutation in exon 11 involving GT insertion that resulted to a stop codon which generated a 29.7 kDa truncated protein product. This is the second documented mutation in BRCA1 exon 11 in a Filipino BC patient since 1998. Initial genotype-phenotype correlations in Filipino BC patients may be elucidated based on screening tests performed. Our results corroborate the findings of a study on unselected incident Filipino BC cases where the reported prevalence of BRCA1 mutation is low. The higher prevalence of putative polypmorphisms may be attributed to the increased stringency in patient prospecting. The Gail, Claus, and BRCAPRO models can be utilized to estimate BC risk in unaffected high-risk individuals but validation is needed. Most of the BRCAPRO and Myriad.com prior probability estimates coincide with the presence of BRCA1 mutation and/or putative polymorphisms. This pioneering

  9. A linear programming model to optimize diets in environmental policy scenarios.

    Science.gov (United States)

    Moraes, L E; Wilen, J E; Robinson, P H; Fadel, J G

    2012-03-01

    The objective was to develop a linear programming model to formulate diets for dairy cattle when environmental policies are present and to examine effects of these policies on diet formulation and dairy cattle nitrogen and mineral excretions as well as methane emissions. The model was developed as a minimum cost diet model. Two types of environmental policies were examined: a tax and a constraint on methane emissions. A tax was incorporated to simulate a greenhouse gas emissions tax policy, and prices of carbon credits in the current carbon markets were attributed to the methane production variable. Three independent runs were made, using carbon dioxide equivalent prices of $5, $17, and $250/t. A constraint was incorporated into the model to simulate the second type of environmental policy, reducing methane emissions by predetermined amounts. The linear programming formulation of this second alternative enabled the calculation of marginal costs of reducing methane emissions. Methane emission and manure production by dairy cows were calculated according to published equations, and nitrogen and mineral excretions were calculated by mass conservation laws. Results were compared with respect to the values generated by a base least-cost model. Current prices of the carbon credit market did not appear onerous enough to have a substantive incentive effect in reducing methane emissions and altering diet costs of our hypothetical dairy herd. However, when emissions of methane were assumed to be reduced by 5, 10, and 13.5% from the base model, total diet costs increased by 5, 19.1, and 48.5%, respectively. Either these increased costs would be passed onto the consumer or dairy producers would go out of business. Nitrogen and potassium excretions were increased by 16.5 and 16.7% with a 13.5% reduction in methane emissions from the base model. Imposing methane restrictions would further increase the demand for grains and other human-edible crops, which is not a progressive

  10. Inside ‘Inside view’ : reflections on stimulating debate and engagement through a multimedia live theatre production on the dilemmas and issues of pre-natal screening policy and practice

    OpenAIRE

    Lewando Hundt, Gillian; Bryanston, Claudette; Lowe, Pam; Cross, Saul; Sandall, Jane; Spencer, Kevin

    2011-01-01

    Background The role of applied theatre in engaging both lay and professional publics with debate on health policy and practice is an emergent field. This paper discusses the development, production performance and discussion of ‘Inside View’.\\ud \\ud Objectives The objectives were to produce applied theatre from research findings of a completed study on genetic prenatal screening, exploring the dilemmas for women and health professionals of prenatal genetic screening, and to engage audiences i...

  11. Modeling policy mix to improve the competitiveness of Indonesian palm oil industry

    Directory of Open Access Journals (Sweden)

    Roland Y H Silitonga

    2016-04-01

    Full Text Available Purpose: The purpose of this research is to develop a model that will explain the impact of government policies to the competitiveness of palm oil industry. The model involves two commodities in this industry, namely crude palm oil (CPO and refined palm oil (RPO, each has different added value. Design/methodology/approach: The model built will define the behavior of government in controlling palm oil industry, and their interactions with macro-environment, in order to improve the competitiveness of the industry. Therefore the first step was to map the main activities in this industry using value chain analysis. After that a conceptual model was built, where the output of the model is competitiveness of the industry based on market share. The third step was model formulation. The model is then utilized to simulate the policy mix given by government in improving the competitiveness of Palm Oil Industry. Research limitations/implications: The model was developed using only some policies which give direct impact to the competitiveness of the industry. For macro environment input, only price is considered in this model. Practical implications: The model can simulate the output of the industry for various government policies mix given to the industry. Originality/value: This research develops a model that can represent the structure and relationship between industry, government and macro environment, using value chain analysis and hierarchical multilevel system approach.

  12. Modeling policy mix to improve the competitiveness of Indonesian palm oil industry

    Energy Technology Data Exchange (ETDEWEB)

    Silitonga, R. Y.H.; Siswanto, J.; Simatupang, T.; Bahagia, S.N.

    2016-07-01

    The purpose of this research is to develop a model that will explain the impact of government policies to the competitiveness of palm oil industry. The model involves two commodities in this industry, namely crude palm oil (CPO) and refined palm oil (RPO), each has different added value. The model built will define the behavior of government in controlling palm oil industry, and their interactions with macro-environment, in order to improve the competitiveness of the industry. Therefore the first step was to map the main activities in this industry using value chain analysis. After that a conceptual model was built, where the output of the model is competitiveness of the industry based on market share. The third step was model formulation. The model is then utilized to simulate the policy mix given by government in improving the competitiveness of Palm Oil Industry. The model was developed using only some policies which give direct impact to the competitiveness of the industry. For macro environment input, only price is considered in this model. The model can simulate the output of the industry for various government policies mix given to the industry. This research develops a model that can represent the structure and relationship between industry, government and macro environment, using value chain analysis and hierarchical multilevel system approach. (Author)

  13. Influence of Screen-Based Peer Modeling on Preschool Children's Vegetable Consumption and Preferences.

    Science.gov (United States)

    Staiano, Amanda E; Marker, Arwen M; Frelier, Johannah M; Hsia, Daniel S; Martin, Corby K

    2016-05-01

    To determine the influence of screen-based peer modeling on children's vegetable consumption and preference. A total of 42 children aged 3-5 years were randomly assigned to view individually a video segment of peers consuming a modeled vegetable (bell pepper), vs a nonfood video segment or no video. Analysis of covariance models examined bell pepper preference and consumption during initial video exposure (day 1) and without video exposure (days 2 and 7), adjusted for age, sex, body mass index, and initial bell pepper consumption. Children in the vegetable condition ate more bell peppers (15.5 g) than did those in the control condition (5.9 g; P = .04; model η(2) = 0.85) on day 7, with no differences on days 1 or 2. Among children who ate the modeled vegetable, those in the vegetable DVD condition reported greater preference for eating the vegetable again (P = .01). Screen-based peer modeling is a promising tool to influence children's vegetable consumption. Copyright © 2016 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

  14. Gene expression profiling in a mouse model identifies fetal liver- and placenta-derived potential biomarkers for Down syndrome screening

    NARCIS (Netherlands)

    Pennings, J.L.A.; Rodenburg, W.; Imholz, S.; Koster, M.P.H.; van Oostrom, C.T.M.; Breit, T.M.; Schielen, P.C.J.I.; de Vries, A.

    2011-01-01

    Background: As a first step to identify novel potential biomarkers for prenatal Down Syndrome screening, we analyzed gene expression in embryos of wild type mice and the Down Syndrome model Ts1Cje. Since current Down Syndrome screening markers are derived from placenta and fetal liver, these tissues

  15. Uncertainty Quantification in High Throughput Screening: Applications to Models of Endocrine Disruption, Cytotoxicity, and Zebrafish Development (GRC Drug Safety)

    Science.gov (United States)

    Using uncertainty quantification, we aim to improve the quality of modeling data from high throughput screening assays for use in risk assessment. ToxCast is a large-scale screening program that analyzes thousands of chemicals using over 800 assays representing hundreds of bioche...

  16. FOSSIL2 energy policy model documentation: FOSSIL2 documentation

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-10-01

    This report discusses the structure, derivations, assumptions, and mathematical formulation of the FOSSIL2 model. Each major facet of the model - supply/demand interactions, industry financing, and production - has been designed to parallel closely the actual cause/effect relationships determining the behavior of the United States energy system. The data base for the FOSSIL2 program is large, as is appropriate for a system dynamics simulation model. When possible, all data were obtained from sources well known to experts in the energy field. Cost and resource estimates are based on DOE data whenever possible. This report presents the FOSSIL2 model at several levels. Volumes II and III of this report list the equations that comprise the FOSSIL2 model, along with variable definitions and a cross-reference list of the model variables. Volume III lists the model equations and a one line definition for equations, in a short, readable format.

  17. Conceptual design of an integrated technology model for carbon policy assessment.

    Energy Technology Data Exchange (ETDEWEB)

    Backus, George A.; Dimotakes, Paul E. (NASA Jet Propulsion Laboratory, Pasadena, CA)

    2011-01-01

    This report describes the conceptual design of a technology choice model for understanding strategies to reduce carbon intensity in the electricity sector. The report considers the major modeling issues affecting technology policy assessment and defines an implementable model construct. Further, the report delineates the basis causal structure of such a model and attempts to establish the technical/algorithmic viability of pursuing model development along with the associated analyses.

  18. Retailer’s optimal ordering policies for EOQ model with imperfective items under a temporary discount

    Directory of Open Access Journals (Sweden)

    Lin Wen Feng

    2016-01-01

    Full Text Available In this article, we study inventory models to determine the optimal special order and maximum saving cost of imperfective items when the supplier offers a temporary discount. The received items are not all perfect and the defectives can be screened out by the end of 100% screening process. Three models are considered according to the special order occurs at regular replenishment time, non-regular replenishment time, and screening time of economic order quantity cycle. Each model has two sub-cases to be discussed. In temporary discount problems, in general, there are integer operators in objective functions. We suggest theorems to find the closed-form solutions to these kinds of problems. Furthermore, numerical examples and sensitivity analysis are given to illustrate the results of the proposed properties and theorems.

  19. Curating and Preparing High-Throughput Screening Data for Quantitative Structure-Activity Relationship Modeling.

    Science.gov (United States)

    Kim, Marlene T; Wang, Wenyi; Sedykh, Alexander; Zhu, Hao

    2016-01-01

    Publicly available bioassay data often contains errors. Curating massive bioassay data, especially high-throughput screening (HTS) data, for Quantitative Structure-Activity Relationship (QSAR) modeling requires the assistance of automated data curation tools. Using automated data curation tools are beneficial to users, especially ones without prior computer skills, because many platforms have been developed and optimized based on standardized requirements. As a result, the users do not need to extensively configure the curation tool prior to the application procedure. In this chapter, a freely available automatic tool to curate and prepare HTS data for QSAR modeling purposes will be described.

  20. Novel use of zebrafish as a vertebrate model to screen radiation protectors and sensitizers

    International Nuclear Information System (INIS)

    Purpose: Zebrafish (Danio rerio) embryos provide a unique vertebrate model to screen therapeutic agents easily and rapidly because of their relatively close genetic relationship to humans, ready abundance and accessibility, short embryonal development, and optical clarity. To validate zebrafish embryos as a screen for radiation modifiers, we evaluated the effects of ionizing radiation in combination with a known radioprotector (free radical scavenger Amifostine) or radiosensitizing agent (tyrosine kinase inhibitor AG1478). Methods and materials: Viable zebrafish embryos were exposed to 0-10 Gy single-fraction 250 kVp X-rays with or without either Amifostine (0-4 mM) or AG1478 (0-10 μM) at defined developmental stages from 1-24 h postfertilization (hpf). Embryos were examined for morphologic abnormalities and viability until 144 hpf. Results: Radiation alone produced a time- and dose-dependent perturbation of normal embryonic development and survival with maximal sensitivity at doses ≥4 Gy delivered before 4 hpf. Amifostine markedly attenuated this effect, whereas AG1478 enhanced teratogenicity and lethality, particularly at therapeutically relevant (2-6 Gy) radiation doses. Conclusions: Collectively, these data validate the use of zebrafish as a vertebrate model to assess the effect of radiation alone or with radiation response modulators. Zebrafish embryos may thus provide a rapid, facile system to screen novel agents ultimately intended for human use in the context of therapeutic or accidental radiation exposure

  1. Addressing the Global Zika Epidemic Locally: An Interprofessional Model of Universal Screening at One Center.

    Science.gov (United States)

    Forman, Rosha N; Mehta, Pooja K; Louis, Kettie R; Finneseth, Molly K; Yarrington, Christina D

    Escalating evidence for the fetal impact of Zika virus infection required a change in care by all prenatal providers. This article describes an effective model of rapid implementation of universal prenatal screening at one hospital and its network of community health centers for a large and diverse immigrant population exploring the challenges, experiences, and lessons learned. Implementation of national recommendations required a workflow change, challenging a system with a heterogeneity of settings and providers. Using a physician clinical champion and advanced practice nurses in the roles of logistical coordinator and liaison to the network, Zika screening was embedded into prenatal intake visits at both the hospital and community health centers. Challenges addressed include varied medical record systems, acceptance by patients, providers, and community health center leadership, as well as culturally appropriate outreach to diverse ethnic and linguistic communities. In 6 months, the prenatal screening rates increased from 20% to 88%, which resulted in the identification of more than 300 pregnant patients at risk of exposure to Zika virus. This model offers key lessons for emergency preparedness in heterogeneous, safety net hospital settings.

  2. The Reserve Force Policy Screening Models (POSM): A User’s Manual

    Science.gov (United States)

    1989-06-01

    to Youth Unemployment for DECISIONS MODULE Example ............................ 70 4. Dependent and Independent Variables Used in Calculations...enlisted part-timer force to meet a growth in strength of 2 percent per year for the next five years under two youth unemployment scenarios: (1...1. The independent variables will appear (see Fig. 21). Currently the table contains only youth unemployment (UNY) and a dummy for each fiscal year

  3. Simulation of reactive geochemical transport in groundwater using a semi-analytical screening model

    Science.gov (United States)

    McNab, Walt W.

    1997-10-01

    A reactive geochemical transport model, based on a semi-analytical solution to the advective-dispersive transport equation in two dimensions, is developed as a screening tool for evaluating the impact of reactive contaminants on aquifer hydrogeochemistry. Because the model utilizes an analytical solution to the transport equation, it is less computationally intensive than models based on numerical transport schemes, is faster, and it is not subject to numerical dispersion effects. Although the assumptions used to construct the model preclude consideration of reactions between the aqueous and solid phases, thermodynamic mineral saturation indices are calculated to provide qualitative insight into such reactions. Test problems involving acid mine drainage and hydrocarbon biodegradation signatures illustrate the utility of the model in simulating essential hydrogeochemical phenomena.

  4. To support growth, to limit emissions: is China a model in terms of climate policy?

    International Nuclear Information System (INIS)

    Voita, Thibault

    2012-05-01

    The objective of this paper is to discuss how China has been able to adapt its economic policy to the challenges of climate change without forgetting its final objective of economic growth for the country. The author first describes some characteristics of the Chinese decision political system in the field of industrial and energy policy towards a low carbon economy: articulation between central power and local authorities, and complexity of decision processes at the central level. The author then shows how this system has changed to integrate policies of struggle against climate change, used them as an opportunity towards a low carbon economy, and put them at the service of the national industrial policy. Then, based on several case studies of actual projects (electric vehicles, gas liquefaction, local energy policies), the author proposes an assessment of the system efficiency, and tries to see whether one can talk of a Chinese political model regarding the policy of struggle against climate change. He notably discusses the efficiency of these policies in terms of relationship between industrial independence and climate policy

  5. What are the implications for policy makers? A systematic review of the cost-effectiveness of screening and brief interventions for alcohol misuse in primary care.

    Directory of Open Access Journals (Sweden)

    Colin eAngus

    2014-09-01

    Full Text Available IntroductionThe efficacy of screening and brief interventions (SBI for excessive alcohol use in primary care is well established; however evidence on their cost-effectiveness is limited. A small number of previous reviews have concluded that SBI programmes are likely to be cost-effective, but these results are equivocal and important questions around the cost-effectiveness implications of key policy decisions such as staffing choices for delivery of SBIs and the intervention duration remain unanswered. MethodsStudies reporting both the costs and a measure of health outcomes of programmes combining screening and brief interventions in primary care were identified by searching MEDLINE, EMBASE, Econlit, the Cochrane Library Database (including NHS EED, CINAHL, PsycINFO, Assia and the Social Science Citation Index and Science Citation Index via Web of Knowledge. Included studies have been stratified both by delivery staff and intervention duration and assessed for quality using the Drummond checklist for economic evaluations.ResultsThe search yielded a total of 23 papers reporting the results of 22 distinct studies. There was significant heterogeneity in methods and outcome measures between studies; however almost all studies reported SBI programmes to be cost-effective. There was no clear evidence that either the duration of the intervention or the delivery staff used had a substantial impact on this result.ConclusionThis review provides strong evidence that SBI programmes in primary care are a cost-effective option for tackling alcohol misuse.

  6. Environmental modelling as an interface between policy and science

    International Nuclear Information System (INIS)

    Blaauboer, R.O.

    1991-01-01

    In this paper some recent developments in environmental modelling in the Netherlands are reviewed from a radiological background. An example is the growing interest in the integration of risk-analysis for exposures to ionizing radiation with that for chemicals and other environmental pollutants. Also since the Chernobyl accident the need of interdisciplinary cooperation, in order to obtain on-line predictive models is more strongly felt. For example atmospheric transport models for chemical pollutants are used for the modelling of the dispersion of radioactive material and vice versa models that were primarily meant for radiation protection purposes are used for other environmental pollutants such as dioxins. At the same time this tendency to integrate and/or couple compartmental models requires harmonization and has its own specific problems. Examples are the difficulties in handling uncertainties, validation, handling of large data bases, correlations between processes in various models and the differing methods and applications of the constituent models (deterministic, probabilistic, for normal or emergency situations etc.). It is thought that the radiological expertise can play an important role in some if not most of these trends in environmental modelling. (9 refs., 1 fig.)

  7. The vortex free energy in the screening phase of the Z(2) Higgs model

    International Nuclear Information System (INIS)

    Meyer, H.

    1983-06-01

    The vortex free energy was proposed to distinguish between the confinement - and the Higgs phase (in the sense of 't Hooft) in lattice gauge theory, when matter fields are present that transform according to an arbitrary representation of the gauge group. In this paper I consider the Z(2) Higgs model and calculate the vortex free energy in the screening part of the confining/screening phase of Fradkin and Shenker. The result does not agree with the expected behavior that corresponds to the structure of the phase diagram. Therefore the vortex free energy is no longer a good indicator for confinement when matter fields transform nontrivially under the center of the gauge group (such as Z(2) Higgs scalars). (orig.)

  8. Identifiability in N-mixture models: a large-scale screening test with bird data.

    Science.gov (United States)

    Kéry, Marc

    2018-02-01

    Binomial N-mixture models have proven very useful in ecology, conservation, and monitoring: they allow estimation and modeling of abundance separately from detection probability using simple counts. Recently, doubts about parameter identifiability have been voiced. I conducted a large-scale screening test with 137 bird data sets from 2,037 sites. I found virtually no identifiability problems for Poisson and zero-inflated Poisson (ZIP) binomial N-mixture models, but negative-binomial (NB) models had problems in 25% of all data sets. The corresponding multinomial N-mixture models had no problems. Parameter estimates under Poisson and ZIP binomial and multinomial N-mixture models were extremely similar. Identifiability problems became a little more frequent with smaller sample sizes (267 and 50 sites), but were unaffected by whether the models did or did not include covariates. Hence, binomial N-mixture model parameters with Poisson and ZIP mixtures typically appeared identifiable. In contrast, NB mixtures were often unidentifiable, which is worrying since these were often selected by Akaike's information criterion. Identifiability of binomial N-mixture models should always be checked. If problems are found, simpler models, integrated models that combine different observation models or the use of external information via informative priors or penalized likelihoods, may help. © 2017 by the Ecological Society of America.

  9. Refugee Policy Implications of U.S. Immigration Medical Screenings: A New Era of Inadmissibility on Health-Related Grounds

    Science.gov (United States)

    Hong, Mi-Kyung; Varghese, Reshma E.; Jindal, Charulata; Efird, Jimmy T.

    2017-01-01

    Refugees frequently face extended delays in their efforts to enter the United States (U.S.) and those who are successful, in many cases, encounter overwhelming obstacles, inadequate resources, and a complex system of legal barriers. Travel restrictions based on equivocal health concerns and a drop in refugee admittance ceilings have complicated the situation. The authors retrieved and analyzed peer-reviewed journal articles, government agency press releases, media postings, epidemiologic factsheets, and relevant lay publications to critically assess U.S. policy regarding refugee resettlement based on health-related grounds. While refugees arguably exhibit an increased incidence of measles and tuberculosis compared with the U.S. population, the legitimacy of the medical examination will be undermined if other diseases that are endemic to refugee populations, yet currently deemed admissible, are used to restrict refugees from entering the U.S. This paper addressees the historic refugee policy of the U.S. and its consequent effect on the health of this vulnerable population. The needs of refugees should be carefully considered in the context of increased disease burden and the associated health care challenges of the country as a whole. PMID:28946650

  10. Refugee Policy Implications of U.S. Immigration Medical Screenings: A New Era of Inadmissibility on Health-Related Grounds.

    Science.gov (United States)

    Hong, Mi-Kyung; Varghese, Reshma E; Jindal, Charulata; Efird, Jimmy T

    2017-09-24

    Refugees frequently face extended delays in their efforts to enter the United States (U.S.) and those who are successful, in many cases, encounter overwhelming obstacles, inadequate resources, and a complex system of legal barriers. Travel restrictions based on equivocal health concerns and a drop in refugee admittance ceilings have complicated the situation. The authors retrieved and analyzed peer-reviewed journal articles, government agency press releases, media postings, epidemiologic factsheets, and relevant lay publications to critically assess U.S. policy regarding refugee resettlement based on health-related grounds. While refugees arguably exhibit an increased incidence of measles and tuberculosis compared with the U.S. population, the legitimacy of the medical examination will be undermined if other diseases that are endemic to refugee populations, yet currently deemed admissible, are used to restrict refugees from entering the U.S. This paper addressees the historic refugee policy of the U.S. and its consequent effect on the health of this vulnerable population. The needs of refugees should be carefully considered in the context of increased disease burden and the associated health care challenges of the country as a whole.

  11. Competing risks model in screening for preeclampsia by maternal characteristics and medical history.

    Science.gov (United States)

    Wright, David; Syngelaki, Argyro; Akolekar, Ranjit; Poon, Leona C; Nicolaides, Kypros H

    2015-07-01

    The purpose of this study was to develop a model for preeclampsia based on maternal demographic characteristics and medical history. This was a screening study of 120,492 singleton pregnancies at 11-13 weeks' gestation, including 2704 pregnancies (2.2%) that experienced preeclampsia. A survival-time model for the gestational age at delivery with preeclampsia was developed from variables of maternal characteristics and history. This approach assumes that, if the pregnancy was to continue indefinitely, all women would experience preeclampsia and that whether they do so or not before a specified gestational age depends on competition between delivery before or after development of preeclampsia. A 5-fold cross validation study was conducted to compare the performance of the new model with the National Institute for Health and Clinical Excellence (NICE) guidelines. In the new model, increased risk for preeclampsia, with a consequent shift in the Gaussian distribution of the gestational age at delivery with preeclampsia to the left, is provided by advancing maternal age, increasing weight, Afro-Caribbean and South Asian racial origin, medical history of chronic hypertension, diabetes mellitus and systemic lupus erythematosus or antiphospholipid syndrome, family history and personal history of preeclampsia, and conception by in vitro fertilization. The risk for preeclampsia decreases with increasing maternal height and in parous women with no previous preeclampsia; in the latter, the protective effect, which is related inversely to the interpregnancy interval, persists beyond 15 years. At a screen-positive rate of 11%, as defined by NICE, the new model predicted 40%, 48%, and 54% of cases of total preeclampsia and preeclampsia requiring delivery at preeclampsia. Such estimation of the a priori risk for preeclampsia is an essential first step in the use of Bayes theorem to combine maternal factors with biomarkers for the continuing development of more effective methods of

  12. Development of small scale cell culture models for screening poloxamer 188 lot-to-lot variation.

    Science.gov (United States)

    Peng, Haofan; Hall, Kaitlyn M; Clayton, Blake; Wiltberger, Kelly; Hu, Weiwei; Hughes, Erik; Kane, John; Ney, Rachel; Ryll, Thomas

    2014-01-01

    Shear protectants such as poloxamer 188 play a critical role in protecting cells during cell culture bioprocessing. Lot-to-lot variation of poloxamer 188 was experienced during a routine technology transfer across sites of similar scale and equipment. Cell culture medium containing a specific poloxamer 188 lot resulted in an unusual drop in cell growth, viability, and titer during manufacturing runs. After switching poloxamer lots, culture performance returned to the expected level. In order to control the quality of poloxamer 188 and thus maintain better consistency in manufacturing, multiple small scale screening models were developed. Initially, a 5L bioreactor model was established to evaluate cell damage by high sparge rates with different poloxamer 188 lots. Subsequently, a more robust, simple, and efficient baffled shake flask model was developed. The baffled shake flask model can be performed in a high throughput manner to investigate the cell damage in a bubbling environment. The main cause of the poor performance was the loss of protection, rather than toxicity. It was also suggested that suspicious lots can be identified using different cell line and media. The screening methods provide easy, yet remarkable models for understanding and controlling cell damage due to raw material lot variation as well as studying the interaction between poloxamer 188 and cells. © 2014 American Institute of Chemical Engineers.

  13. A sparse QSRR model for predicting retention indices of essential oils based on robust screening approach.

    Science.gov (United States)

    Al-Fakih, A M; Algamal, Z Y; Lee, M H; Aziz, M

    2017-08-01

    A robust screening approach and a sparse quantitative structure-retention relationship (QSRR) model for predicting retention indices (RIs) of 169 constituents of essential oils is proposed. The proposed approach is represented in two steps. First, dimension reduction was performed using the proposed modified robust sure independence screening (MR-SIS) method. Second, prediction of RIs was made using the proposed robust sparse QSRR with smoothly clipped absolute deviation (SCAD) penalty (RSQSRR). The RSQSRR model was internally and externally validated based on [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], Y-randomization test, [Formula: see text], [Formula: see text], and the applicability domain. The validation results indicate that the model is robust and not due to chance correlation. The descriptor selection and prediction performance of the RSQSRR for training dataset outperform the other two used modelling methods. The RSQSRR shows the highest [Formula: see text], [Formula: see text], and [Formula: see text], and the lowest [Formula: see text]. For the test dataset, the RSQSRR shows a high external validation value ([Formula: see text]), and a low value of [Formula: see text] compared with the other methods, indicating its higher predictive ability. In conclusion, the results reveal that the proposed RSQSRR is an efficient approach for modelling high dimensional QSRRs and the method is useful for the estimation of RIs of essential oils that have not been experimentally tested.

  14. Development of a receptor model for efficient in silico screening of HIV-1 integrase inhibitors.

    Science.gov (United States)

    Quevedo, Mario A; Ribone, Sergio R; Briñón, Margarita C; Dehaen, Wim

    2014-07-01

    Integrase (IN) is a key viral enzyme for the replication of the type-1 human immunodeficiency virus (HIV-1), and as such constitutes a relevant therapeutic target for the development of anti-HIV agents. However, the lack of crystallographic data of HIV IN complexed with the corresponding viral DNA has historically hindered the application of modern structure-based drug design techniques to the discovery of new potent IN inhibitors (INIs). Consequently, the development and validation of reliable HIV IN structural models that may be useful for the screening of large databases of chemical compounds is of particular interest. In this study, four HIV-1 IN homology models were evaluated respect to their capability to predict the inhibition potency of a training set comprising 36 previously reported INIs with IC50 values in the low nanomolar to the high micromolar range. Also, 9 inactive structurally related compounds were included in this training set. In addition, a crystallographic structure of the IN-DNA complex corresponding to the prototype foamy virus (PFV) was also evaluated as structural model for the screening of inhibitors. The applicability of high throughput screening techniques, such as blind and ligand-guided exhaustive rigid docking was assessed. The receptor models were also refined by molecular dynamics and clustering techniques to assess protein sidechain flexibility and solvent effect on inhibitor binding. Among the studied models, we conclude that the one derived from the X-ray structure of the PFV integrase exhibited the best performance to rank the potencies of the compounds in the training set, with the predictive power being further improved by explicitly modeling five water molecules within the catalytic side of IN. Also, accounting for protein sidechain flexibility enhanced the prediction of inhibition potencies among the studied compounds. Finally, an interaction fingerprint pattern was established for the fast identification of potent IN

  15. Policy insights from the nutritional food market transformation model: the case of obesity prevention.

    Science.gov (United States)

    Struben, Jeroen; Chan, Derek; Dubé, Laurette

    2014-12-01

    This paper presents a system dynamics policy model of nutritional food market transformation, tracing over-time interactions between the nutritional quality of supply, consumer food choice, population health, and governmental policy. Applied to the Canadian context and with body mass index as the primary outcome, we examine policy portfolios for obesity prevention, including (1) industry self-regulation efforts, (2) health- and nutrition-sensitive governmental policy, and (3) efforts to foster health- and nutrition-sensitive innovation. This work provides novel theoretical and practical insights on drivers of nutritional market transformations, highlighting the importance of integrative policy portfolios to simultaneously shift food demand and supply for successful and self-sustaining nutrition and health sensitivity. We discuss model extensions for deeper and more comprehensive linkages of nutritional food market transformation with supply, demand, and policy in agrifood and health/health care. These aim toward system design and policy that can proactively, and with greater impact, scale, and resilience, address single as well as double malnutrition in varying country settings. © 2014 New York Academy of Sciences.

  16. A Model-Driven Architecture Approach for Modeling, Specifying and Deploying Policies in Autonomous and Autonomic Systems

    Science.gov (United States)

    Pena, Joaquin; Hinchey, Michael G.; Sterritt, Roy; Ruiz-Cortes, Antonio; Resinas, Manuel

    2006-01-01

    Autonomic Computing (AC), self-management based on high level guidance from humans, is increasingly gaining momentum as the way forward in designing reliable systems that hide complexity and conquer IT management costs. Effectively, AC may be viewed as Policy-Based Self-Management. The Model Driven Architecture (MDA) approach focuses on building models that can be transformed into code in an automatic manner. In this paper, we look at ways to implement Policy-Based Self-Management by means of models that can be converted to code using transformations that follow the MDA philosophy. We propose a set of UML-based models to specify autonomic and autonomous features along with the necessary procedures, based on modification and composition of models, to deploy a policy as an executing system.

  17. Modelling and Analysing Access Control Policies in XACML 3.0

    DEFF Research Database (Denmark)

    Ramli, Carroline Dewi Puspa Kencana

    and verification of properties of XACML policies. Overall, we focus into two different area. The first part focuses on the access control language. More specifically our focus is on the understanding XACML 3.0. The second part focuses on how we use Logic Programming (LP) to model access control policies. We show...... semantics is described normatively using natural language. The use of English text in standardisation leads to the risk of misinterpretation and ambiguity. In order to avoid this drawback, we define an abstract syntax of XACML 3.0 and a formal XACML semantics. Second, we propose a logic-based XACML analysis...... framework using Answer Set Programming (ASP). With ASP we model an XACML PDP that loads XACML policies and evaluates XACML requests against these policies. The expressivity of ASP and the existence of efficient implementations of the answer set semantics provide the means for declarative specification...

  18. Clearing the air : Air quality modelling for policy support

    NARCIS (Netherlands)

    Hendriks, C.

    2018-01-01

    The origin of particulate matter (PM) concentrations in the Netherlands is established using the LOTOS-EUROS model with a source attribution module. Emissions from the ten main economic sectors (SNAP1) were tracked, separating Dutch and foreign sources. Of the modelled PM10 in the Netherlands, about

  19. Prenatal screening and genetics

    DEFF Research Database (Denmark)

    Alderson, P; Aro, A R; Dragonas, T

    2001-01-01

    Although the term 'genetic screening' has been used for decades, this paper discusses how, in its most precise meaning, genetic screening has not yet been widely introduced. 'Prenatal screening' is often confused with 'genetic screening'. As we show, these terms have different meanings, and we...... examine definitions of the relevant concepts in order to illustrate this point. The concepts are i) prenatal, ii) genetic screening, iii) screening, scanning and testing, iv) maternal and foetal tests, v) test techniques and vi) genetic conditions. So far, prenatal screening has little connection...... with precisely defined genetics. There are benefits but also disadvantages in overstating current links between them in the term genetic screening. Policy making and professional and public understandings about screening could be clarified if the distinct meanings of prenatal screening and genetic screening were...

  20. An endogenous Taylor condition in an endogenous growth monetary policy model

    OpenAIRE

    Le, Mai Vo; Gillman, Max; Minford, Patrick

    2007-01-01

    The paper derives a Taylor condition as part of the agent's equilibrium behavior in an endogenous growth monetary economy. It shows the assumptions necessary to make it almost identical to the original Taylor rule, and that it can interchangably take a money supply growth rate form. From the money supply form, simple policy experiments are conducted. A full central bank policy model is derived that includes the Taylor condition along with equations comparable to the standard aggregate-demand/...

  1. A simulation model for reliability-based appraisal of an energy policy: The case of Lebanon

    International Nuclear Information System (INIS)

    Hamdan, H.A.; Ghajar, R.F.; Chedid, R.B.

    2012-01-01

    The Lebanese Electric Power System (LEPS) has been suffering from technical and financial deficiencies for decades and mirrors the problems encountered in many developing countries suffering from inadequate or no power systems planning resulting in incomplete and ill-operating infrastructure, and suffering from effects of political instability, huge debts, unavailability of financing desired projects and inefficiency in operation. The upgrade and development of the system necessitate the adoption of a comprehensive energy policy that introduces solutions to a diversity of problems addressing the technical, financial, administrative and governance aspects of the system. In this paper, an energy policy for Lebanon is proposed and evaluated based on integration between energy modeling and financial modeling. The paper utilizes the Load Modification Technique (LMT) as a probabilistic tool to assess the impact of policy implementation on energy production, overall cost, technical/commercial losses and reliability. Scenarios reflecting implementation of policy projects are assessed and their impacts are compared with business-as-usual scenarios which assume no new investment is to take place in the sector. Conclusions are drawn on the usefulness of the proposed evaluation methodology and the effectiveness of the adopted energy policy for Lebanon and other developing countries suffering from similar power system problems. - Highlights: ► Evaluation methodology based on a probabilistic simulation tool is proposed. ► A business-as-usual scenario for a given study period of the LEPS was modeled. ► Mitigation scenarios reflecting implementation of the energy policy are modeled. ► Policy simulated and compared with business-as-usual scenarios of the LEPS. ► Results reflect usefulness of proposed methodology and the adopted energy policy.

  2. Transport energy demand: techno-economic modelling and scenarios for Irish climate policy

    OpenAIRE

    Daly, Hannah E.

    2012-01-01

    The case for energy policy modelling is strong in Ireland, where stringent EU climate targets are projected to be overshot by 2015. Policy targets aiming to deliver greenhouse gas and renewable energy targets have been made, but it is unclear what savings are to be achieved and from which sectors. Concurrently, the growth of personal mobility has caused an astonishing increase in CO2 emissions from private cars in Ireland, a 37% rise between 2000 and 2008, and while there have been improvemen...

  3. Discharge Fee Policy Analysis: A Computable General Equilibrium (CGE) Model of Water Resources and Water Environments

    OpenAIRE

    Guohua Fang; Ting Wang; Xinyi Si; Xin Wen; Yu Liu

    2016-01-01

    To alleviate increasingly serious water pollution and shortages in developing countries, various kinds of policies have been implemented by local governments. It is vital to quantify and evaluate the performance and potential economic impacts of these policies. This study develops a Computable General Equilibrium (CGE) model to simulate the regional economic and environmental effects of discharge fees. Firstly, water resources and water environment factors are separated from the input and out...

  4. Policy Subsystem Portfolio Management: A Neural Network Model of the Gulf of Mexico Program

    OpenAIRE

    Larkin, George Richard

    1999-01-01

    This study provides insights into the behavior of an environmental policy subsystem. The study uses neural network theory to model the Gulf of Mexico Program's allocation of implementation funds. The Gulf of Mexico Program is a prototype effort to institutionalize a policy subsystem. A project implementation fund is at the core of the Gulf of Mexico Program. The United States Environmental Protection Agency provides the implementation fund and the Mexico Program Office (GMPO) administers it. ...

  5. FOSSIL2 energy policy model documentation: FOSSIL2 documentation

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-10-01

    This report discusses the structure, derivations, assumptions, and mathematical formulation of the FOSSIL2 model. Each major facet of the model - supply/demand interactions, industry financing, and production - has been designed to parallel closely the actual cause/effect relationships determining the behavior of the United States energy system. The data base for the FOSSIL2 program is large, as is appropriate for a system dynamics simulation model. When possible, all data were obtained from sources well known to experts in the energy field. Cost and resource estimates are based on DOE data whenever possible. This report presents the FOSSIL2 model at several levels. Volumes II and III of this report list the equations that comprise the FOSSIL2 model, along with variable definitions and a cross-reference list of the model variables. Volume II provides the model equations with each of their variables defined, while Volume III lists the equations, and a one line definition for equations, in a shorter, more readable format.

  6. An alternative screening model for the estimation of outdoor air concentration at large contaminated sites

    Science.gov (United States)

    Verginelli, Iason; Nocentini, Massimo; Baciocchi, Renato

    2017-09-01

    Simplified analytical solutions of fate and transport models are often used to carry out risk assessment on contaminated sites, to evaluate the long-term air quality in relation to volatile organic compounds in either soil or groundwater. Among the different assumptions employed to develop these solutions, in this work we focus on those used in the ASTM-RBCA ;box model; for the evaluation of contaminant dispersion in the atmosphere. In this simple model, it is assumed that the contaminant volatilized from the subsurface is dispersed in the atmosphere within a mixing height equal to two meters, i.e. the height of the breathing zone. In certain cases, this simplification could lead to an overestimation of the outdoor air concentration at the point of exposure. In this paper we first discuss the maximum source lengths (in the wind direction) for which the application of the ;box model; can be considered acceptable. Specifically, by comparing the results of ;box model; with the SCREEN3 model of U.S.EPA we found that under very stable atmospheric conditions (class F) the ASTM-RBCA approach provides acceptable results for source lengths up to 200 m while for very unstable atmospheric conditions (class A and B) the overestimation of the concentrations at the point of the exposure can be already observed for source lengths of only 10 m. In the latter case, the overestimation of the ;box model; can be of more than one order of magnitude for source lengths above 500 m. To overcome this limitation, in this paper we introduce a simple analytical solution that can be used for the calculation of the concentration at the point of exposure for large contaminated sites. The method consists in the introduction of an equivalent mixing zone height that allows to account for the dispersion of the contaminants along the source length while keeping the simplistic ;box model; approach that is implemented in most of risk assessment tools that are based on the ASTM-RBCA standard (e.g. RBCA

  7. Tobacco Town: Computational Modeling of Policy Options to Reduce Tobacco Retailer Density.

    Science.gov (United States)

    Luke, Douglas A; Hammond, Ross A; Combs, Todd; Sorg, Amy; Kasman, Matt; Mack-Crane, Austen; Ribisl, Kurt M; Henriksen, Lisa

    2017-05-01

    To identify the behavioral mechanisms and effects of tobacco control policies designed to reduce tobacco retailer density. We developed the Tobacco Town agent-based simulation model to examine 4 types of retailer reduction policies: (1) random retailer reduction, (2) restriction by type of retailer, (3) limiting proximity of retailers to schools, and (4) limiting proximity of retailers to each other. The model examined the effects of these policies alone and in combination across 4 different types of towns, defined by 2 levels of population density (urban vs suburban) and 2 levels of income (higher vs lower). Model results indicated that reduction of retailer density has the potential to decrease accessibility of tobacco products by driving up search and purchase costs. Policy effects varied by town type: proximity policies worked better in dense, urban towns whereas retailer type and random retailer reduction worked better in less-dense, suburban settings. Comprehensive retailer density reduction policies have excellent potential to reduce the public health burden of tobacco use in communities.

  8. Combining agent-based modeling and life cycle assessment for the evaluation of mobility policies.

    Science.gov (United States)

    Florent, Querini; Enrico, Benetto

    2015-02-03

    This article presents agent-based modeling (ABM) as a novel approach for consequential life cycle assessment (C-LCA) of large scale policies, more specifically mobility-related policies. The approach is validated at the Luxembourgish level (as a first case study). The agent-based model simulates the car market (sales, use, and dismantling) of the population of users in the period 2013-2020, following the implementation of different mobility policies and available electric vehicles. The resulting changes in the car fleet composition as well as the hourly uses of the vehicles are then used to derive consistent LCA results, representing the consequences of the policies. Policies will have significant environmental consequences: when using ReCiPe2008, we observe a decrease of global warming, fossil depletion, acidification, ozone depletion, and photochemical ozone formation and an increase of metal depletion, ionizing radiations, marine eutrophication, and particulate matter formation. The study clearly shows that the extrapolation of LCA results for the circulating fleet at national scale following the introduction of the policies from the LCAs of single vehicles by simple up-scaling (using hypothetical deployment scenarios) would be flawed. The inventory has to be directly conducted at full scale and to this aim, ABM is indeed a promising approach, as it allows identifying and quantifying emerging effects while modeling the Life Cycle Inventory of vehicles at microscale through the concept of agents.

  9. Determining the privacy policy deficiencies of health ICT applications through semi-formal modelling.

    Science.gov (United States)

    Croll, Peter R

    2011-02-01

    To ensure that patient confidentiality is securely maintained, health ICT applications that contain sensitive personal information demand comprehensive privacy policies. Determining the adequacy of these policies to meet legal conformity together with clinical users and patient expectation is demanding in practice. Organisations and agencies looking to analyse their Privacy and Security policies can benefit from guidance provided by outside entities such as the Privacy Office of their State or Government together with law firms and ICT specialists. The advice given is not uniform and often open to different interpretations. Of greater concern is the possibility of overlooking any important aspects that later result in a data breach. Based on three case studies, this paper considers whether a more formal approach to privacy analysis could be taken that would help identify the full coverage of a Privacy Impact Analysis and determine the deficiencies with an organisation's current policies and approach. A diagrammatic model showing the relationships between Confidentiality, Privacy, Trust, Security and Safety is introduced. First the validity of this model is determined by mapping it against the real-world case studies taken from three healthcare services that depend on ICT. Then, by using software engineering methods, a formal mapping of the relationships is undertaken to identify a full set of policies needed to satisfy the model. How effective this approach may prove as a generic method for deriving a comprehensive set of policies in health ICT applications is finally discussed. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  10. Asbestos Model Accreditation Plan (MAP) Enforcement Response Policy

    Science.gov (United States)

    The Asbestos Model Accreditation Plan (MAP) (40 CFR 763 Subpart E Appendix C) mandates safety training for those who do asbestos removal work, and implements the additional training requirements mandated by Congress

  11. The SSI TOOLBOX Source Term Model SOSIM - Screening for important radionuclides and parameter sensitivity analysis

    International Nuclear Information System (INIS)

    Avila Moreno, R.; Barrdahl, R.; Haegg, C.

    1995-05-01

    The main objective of the present study was to carry out a screening and a sensitivity analysis of the SSI TOOLBOX source term model SOSIM. This model is a part of the SSI TOOLBOX for radiological impact assessment of the Swedish disposal concept for high-level waste KBS-3. The outputs of interest for this purpose were: the total released fraction, the time of total release, the time and value of maximum release rate, the dose rates after direct releases of the biosphere. The source term equations were derived and simple equations and methods were proposed for calculation of these. A literature survey has been performed in order to determine a characteristic variation range and a nominal value for each model parameter. In order to reduce the model uncertainties the authors recommend a change in the initial boundary condition for solution of the diffusion equation for highly soluble nuclides. 13 refs

  12. Ligand Based Pharmacophore Modeling and Virtual Screening Studies to Design Novel HDAC2 Inhibitors

    Directory of Open Access Journals (Sweden)

    Naresh Kandakatla

    2014-01-01

    Full Text Available Histone deacetylases 2 (HDAC2, Class I histone deacetylase (HDAC family, emerged as an important therapeutic target for the treatment of various cancers. A total of 48 inhibitors of two different chemotypes were used to generate pharmacophore model using 3D QSAR pharmacophore generation (HypoGen algorithm module in Discovery Studio. The best HypoGen model consists of four pharmacophore features namely, one hydrogen bond acceptor (HBA, and one hydrogen donor (HBD, one hydrophobic (HYP and one aromatic centres, (RA. This model was validated against 20 test set compounds and this model was utilized as a 3D query for virtual screening to validate against NCI and Maybridge database and the hits further screened by Lipinski’s rule of 5, and a total of 382 hit compounds from NCI and 243 hit compounds from Maybridge were found and were subjected to molecular docking in the active site of HDAC2 (PDB: 3MAX. Finally eight hit compounds, NSC108392, NSC127064, NSC110782, and NSC748337 from NCI database and MFCD01935795, MFCD00830779, MFCD00661790, and MFCD00124221 from Maybridge database, were considered as novel potential HDAC2 inhibitors.

  13. A role for low-order system dynamics models in urban health policy making.

    Science.gov (United States)

    Newell, Barry; Siri, José

    2016-10-01

    Cities are complex adaptive systems whose responses to policy initiatives emerge from feedback interactions between their parts. Urban policy makers must routinely deal with both detail and dynamic complexity, coupled with high levels of diversity, uncertainty and contingency. In such circumstances, it is difficult to generate reliable predictions of health-policy outcomes. In this paper we explore the potential for low-order system dynamics (LOSD) models to make a contribution towards meeting this challenge. By definition, LOSD models have few state variables (≤5), illustrate the non-linear effects caused by feedback and accumulation, and focus on endogenous dynamics generated within well-defined boundaries. We suggest that experience with LOSD models can help practitioners to develop an understanding of basic principles of system dynamics, giving them the ability to 'see with new eyes'. Because efforts to build a set of LOSD models can help a transdisciplinary group to develop a shared, coherent view of the problems that they seek to tackle, such models can also become the foundations of 'powerful ideas'. Powerful ideas are conceptual metaphors that provide the members of a policy-making group with the a priori shared context required for effective communication, the co-production of knowledge, and the collaborative development of effective public health policies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. An Object-Oriented Information Model for Policy-based Management of Distributed Applications

    NARCIS (Netherlands)

    Diaz, G.; Gay, V.C.J.; Horlait, E.; Hamza, M.H.

    2002-01-01

    This paper presents an object-oriented information model to support a policy-based management for distributed multimedia applications. The information base contains application-level information about the users, the applications, and their profile. Our Information model is described in details and

  15. Model Proposition for the Fiscal Policies Analysis Applied in Economic Field

    Directory of Open Access Journals (Sweden)

    Larisa Preda

    2007-05-01

    Full Text Available This paper presents a study about fiscal policy applied in economic development. Correlations between macroeconomics and fiscal indicators signify the first steep in our analysis. Next step is a new model proposal for the fiscal and budgetary choices. This model is applied on the date of the Romanian case.

  16. Integration of Generic Multi-dimensional Model and Operational Policies for Batch Cooling Crystallization

    DEFF Research Database (Denmark)

    Abdul Samad, Noor Asma Fazli; Singh, Ravendra; Sin, Gürkan

    2011-01-01

    A generic multi-dimensional modeling framework for studying batch cooling crystallization processes under generated operational policies is presented. The generic nature of the modeling allows the study of a wide range of chemical systems under different operational scenarios, enabling thereby, t...

  17. HIV prevention policy and programme planning: What can mathematical modelling contribute?

    NARCIS (Netherlands)

    Hankins, C.A.

    2014-01-01

    This thesis explores the potential contribution of mathematical modelling to informed decision-making on policy and programme planning for novel HIV prevention tools. Its hypothesis is that, under certain conditions, modelling results can be a useful addition to the evidence and other factors that

  18. Improving virtual screening predictive accuracy of Human kallikrein 5 inhibitors using machine learning models.

    Science.gov (United States)

    Fang, Xingang; Bagui, Sikha; Bagui, Subhash

    2017-08-01

    The readily available high throughput screening (HTS) data from the PubChem database provides an opportunity for mining of small molecules in a variety of biological systems using machine learning techniques. From the thousands of available molecular descriptors developed to encode useful chemical information representing the characteristics of molecules, descriptor selection is an essential step in building an optimal quantitative structural-activity relationship (QSAR) model. For the development of a systematic descriptor selection strategy, we need the understanding of the relationship between: (i) the descriptor selection; (ii) the choice of the machine learning model; and (iii) the characteristics of the target bio-molecule. In this work, we employed the Signature descriptor to generate a dataset on the Human kallikrein 5 (hK 5) inhibition confirmatory assay data and compared multiple classification models including logistic regression, support vector machine, random forest and k-nearest neighbor. Under optimal conditions, the logistic regression model provided extremely high overall accuracy (98%) and precision (90%), with good sensitivity (65%) in the cross validation test. In testing the primary HTS screening data with more than 200K molecular structures, the logistic regression model exhibited the capability of eliminating more than 99.9% of the inactive structures. As part of our exploration of the descriptor-model-target relationship, the excellent predictive performance of the combination of the Signature descriptor and the logistic regression model on the assay data of the Human kallikrein 5 (hK 5) target suggested a feasible descriptor/model selection strategy on similar targets. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Alternative policy impacts on US GHG emissions and energy security: A hybrid modeling approach

    International Nuclear Information System (INIS)

    Sarica, Kemal; Tyner, Wallace E.

    2013-01-01

    This study addresses the possible impacts of energy and climate policies, namely corporate average fleet efficiency (CAFE) standard, renewable fuel standard (RFS) and clean energy standard (CES), and an economy wide equivalent carbon tax on GHG emissions in the US to the year 2045. Bottom–up and top–down modeling approaches find widespread use in energy economic modeling and policy analysis, in which they differ mainly with respect to the emphasis placed on technology of the energy system and/or the comprehensiveness of endogenous market adjustments. For this study, we use a hybrid energy modeling approach, MARKAL–Macro, that combines the characteristics of two divergent approaches, in order to investigate and quantify the cost of climate policies for the US and an equivalent carbon tax. The approach incorporates Macro-economic feedbacks through a single sector neoclassical growth model while maintaining sectoral and technological detail of the bottom–up optimization framework with endogenous aggregated energy demand. Our analysis is done for two important objectives of the US energy policy: GHG reduction and increased energy security. Our results suggest that the emission tax achieves results quite similar to the CES policy but very different results in the transportation sector. The CAFE standard and RFS are more expensive than a carbon tax for emission reductions. However, the CAFE standard and RFS are much more efficient at achieving crude oil import reductions. The GDP losses are 2.0% and 1.2% relative to the base case for the policy case and carbon tax. That difference may be perceived as being small given the increased energy security gained from the CAFE and RFS policy measures and the uncertainty inherent in this type of analysis. - Highlights: • Evaluates US impacts of three energy/climate policies and a carbon tax (CT) • Analysis done with bottom–up MARKAL model coupled with a macro model • Electricity clean energy standard very close to

  20. The transtheoretical model, health belief model, and breast cancer screening among Iranian women with a family history of breast cancer.

    Science.gov (United States)

    Farajzadegan, Ziba; Fathollahi-Dehkordi, Fariba; Hematti, Simin; Sirous, Reza; Tavakoli, Neda; Rouzbahani, Reza

    2016-01-01

    Participation of Iranian women with a family history of breast cancer in breast cancer screening programs is low. This study evaluates the compliance of women having a family history of breast cancer with clinical breast exam (CBE) according to the stage of transtheoretical model (TTM) and health belief model (HBM). In this cross-sectional study, we used Persian version of champion's HBM scale to collect factors associated with TTM stages applied to screening from women over 20 years and older. The obtained data were analyzed by SPSS, using descriptive statistics, Chi-square test, independent t -test, and analysis of covariance. Final sample size was 162 women. Thirty-three percent were in action/maintenance stage. Older women, family history of breast cancer in first-degree relatives, personal history of breast disease, insurance coverage, and a history of breast self-examination were associated with action/maintenance stage. Furthermore, women in action/maintenance stages had significantly fewer perceived barriers in terms of CBE in comparison to women in other stages ( P 0.05). The finding indicates that the rate of women in action/maintenance stage of CBE is low. Moreover, results show a strong association between perceived barriers and having a regular CBE. These clarify the necessity of promoting national target programs for breast cancer screening, which should be considered as the first preference for reducing CBE barriers.

  1. Dual Binding Site and Selective Acetylcholinesterase Inhibitors Derived from Integrated Pharmacophore Models and Sequential Virtual Screening

    Directory of Open Access Journals (Sweden)

    Shikhar Gupta

    2014-01-01

    Full Text Available In this study, we have employed in silico methodology combining double pharmacophore based screening, molecular docking, and ADME/T filtering to identify dual binding site acetylcholinesterase inhibitors that can preferentially inhibit acetylcholinesterase and simultaneously inhibit the butyrylcholinesterase also but in the lesser extent than acetylcholinesterase. 3D-pharmacophore models of AChE and BuChE enzyme inhibitors have been developed from xanthostigmine derivatives through HypoGen and validated using test set, Fischer’s randomization technique. The best acetylcholinesterase and butyrylcholinesterase inhibitors pharmacophore hypotheses Hypo1_A and Hypo1_B, with high correlation coefficient of 0.96 and 0.94, respectively, were used as 3D query for screening the Zinc database. The screened hits were then subjected to the ADME/T and molecular docking study to prioritise the compounds. Finally, 18 compounds were identified as potential leads against AChE enzyme, showing good predicted activities and promising ADME/T properties.

  2. Microglia-Based Phenotypic Screening Identifies a Novel Inhibitor of Neuroinflammation Effective in Alzheimer's Disease Models.

    Science.gov (United States)

    Zhou, Wei; Zhong, Guifa; Fu, Sihai; Xie, Hui; Chi, Tianyan; Li, Luyi; Rao, Xiurong; Zeng, Shaogao; Xu, Dengfeng; Wang, Hao; Sheng, Guoqing; Ji, Xing; Liu, Xiaorong; Ji, Xuefei; Wu, Donghai; Zou, Libo; Tortorella, Micky; Zhang, Kejian; Hu, Wenhui

    2016-11-16

    Currently, anti-AD drug discovery using target-based approaches is extremely challenging due to unclear etiology of AD and absence of validated therapeutic protein targets. Neuronal death, regardless of causes, plays a key role in AD progression, and it is directly linked to neuroinflammation. Meanwhile, phenotypic screening is making a resurgence in drug discovery process as an alternative to target-focused approaches. Herein, we employed microglia-based phenotypic screenings to search for small molecules that modulate the release of detrimental proinflammatory cytokines. The identified novel pharmacological inhibitor of neuroinflammation (named GIBH-130) was validated to alter phenotypes of neuroinflammation in AD brains. Notably, this molecule exhibited comparable in vivo efficacy of cognitive impairment relief to donepezil and memantine respectively in both β amyloid-induced and APP/PS1 double transgenic Alzheimer's murine models at a substantially lower dose (0.25 mg/kg). Therefore, GIBH-130 constitutes a unique chemical probe for pathogenesis research and drug development of AD, and it also suggests microglia-based phenotypic screenings that target neuroinflammation as an effective and feasible strategy to identify novel anti-AD agents.

  3. High Throughput Screen for Novel Antimicrobials using a Whole Animal Infection Model

    Science.gov (United States)

    Moy, Terence I.; Conery, Annie L.; Larkins-Ford, Jonah; Wu, Gang; Mazitschek, Ralph; Casadei, Gabriele; Lewis, Kim; Carpenter, Anne E.; Ausubel, Frederick M.

    2009-01-01

    The nematode Caenorhabditis elegans is a unique whole animal model system for identifying small molecules with in vivo anti-infective properties. C. elegans can be infected with a broad range of human pathogens, including Enterococcus faecalis, an important human nosocomial pathogen with a mortality rate of up to 37% that is increasingly acquiring resistance to antibiotics. Here, we describe an automated, high throughput screen of 37,200 compounds and natural product extracts for those that enhance survival of C. elegans infected with E. faecalis. The screen uses a robot to accurately dispense live, infected animals into 384-well plates, and automated microscopy and image analysis to generate quantitative, high content data. We identified 28 compounds and extracts that were not previously reported to have antimicrobial properties, including 6 structural classes that cure infected C. elegans animals but do not affect the growth of the pathogen in vitro, thus acting by a mechanism of action distinct from antibiotics currently in clinical use. Our versatile and robust screening system can be easily adapted for other whole animal assays to probe a broad range of biological processes. PMID:19572548

  4. Survey of breast cancer mammography screening behaviors in Eastern Taiwan based on a health belief model

    Directory of Open Access Journals (Sweden)

    Wen-Li Wang

    2014-08-01

    Full Text Available Breast cancer is the main form of cancer affecting women and the fourth most common cause of cancer mortality in women. The aim of this study was to explore regular mammography screening in Hualien women and to identify the factors that influence its uptake based on a health belief model. This cross-sectional study was performed between July 2012 and December 2012. A total of 776 women aged 45–69 years were enrolled in the study. The results of crude and adjusted analyses showed that there were significant differences in the prevalence of regular mammography screening, which were related to different age groups, residence areas, educational levels, hormone replacement therapy status, and history of breast cancer. Women in the older age groups, with a higher educational level, in receipt of hormone replacement therapy, and with a personal history of breast cancer had significantly higher odds ratios for regular mammography screening (2.75, 1.68, 1.75, and 1.98, respectively; all p < 0.05.

  5. A multiple perspective modeling and simulation approach for renewable energy policy evaluation

    Science.gov (United States)

    Alyamani, Talal M.

    Environmental issues and reliance on fossil fuel sources, including coal, oil, and natural gas, are the two most common energy issues that are currently faced by the United States (U.S.). Incorporation of renewable energy sources, a non-economical option in electricity generation compared to conventional sources that burn fossil fuels, single handedly promises a viable solution for both of these issues. Several energy policies have concordantly been suggested to reduce the financial burden of adopting renewable energy technologies and make such technologies competitive with conventional sources throughout the U.S. This study presents a modeling and analysis approach for comprehensive evaluation of renewable energy policies with respect to their benefits to various related stakeholders--customers, utilities, governmental and environmental agencies--where the debilitating impacts, advantages, and disadvantages of such policies can be assessed and quantified at the state level. In this work, a novel simulation framework is presented to help policymakers promptly assess and evaluate policies from different perspectives of its stakeholders. The proposed framework is composed of four modules: 1) a database that collates the economic, operational, and environmental data; 2) elucidation of policy, which devises the policy for the simulation model; 3) a preliminary analysis, which makes predictions for consumption, supply, and prices; and 4) a simulation model. After the validity of the proposed framework is demonstrated, a series of planned Florida and Texas renewable energy policies are implemented into the presented framework as case studies. Two solar and one energy efficiency programs are selected as part of the Florida case study. A utility rebate and federal tax credit programs are selected as part of the Texas case study. The results obtained from the simulation and conclusions drawn on the assessment of current energy policies are presented with respect to the

  6. Screening, brief intervention and referral to treatment (SBIRT): implementation barriers, facilitators and model migration.

    Science.gov (United States)

    Vendetti, Janice; Gmyrek, Amanda; Damon, Donna; Singh, Manu; McRee, Bonnie; Del Boca, Frances

    2017-02-01

    To identify barriers and facilitators associated with initial implementation of a US alcohol and other substance use Screening, Brief Intervention, and Referral to Treatment (SBIRT) grant program, and to identify modifications in program design that addressed implementation challenges. A mixed-method approach used quantitative and qualitative data, including SBIRT provider ratings of implementation barriers and facilitators, staff interview responses and program documentation. Multiple sites within the first seven programs funded in a national demonstration program in the United States. One hundred and two SBIRT providers were surveyed; 221 SBIRT stakeholders and staff were interviewed. Mean ratings of barriers and facilitators were calculated using provider survey responses. An inductive content analysis of interview responses identified factors perceived to support and challenge implementation; program modifications that occurred over time were recorded. Providers rated pre-selected implementation facilitators higher than barriers. Content analysis of interview responses revealed six themes: committed leaders; intra- and inter-organizational communication/collaboration; provider buy-in and model acceptance; contextual factors; quality assurance; and grant requirements. Over time, programs tended to: adopt more efficient 'pre-screen' item sets; screen for risk factors in addition to alcohol/substance use; use contracted specialists to deliver SBIRT services; conduct services in high-volume emergency department and trauma center settings; and implement on-site and telephonic treatment delivery. Screening, Brief Intervention and Referral to Treatment program implementation in the United States is facilitated by committed leadership and the use of substance use specialists, rather than medical generalists, to deliver services. Many implementation challenges can be addressed by an adequate start-up phase focused on comprehensive education and training, and on the

  7. Transportation network policy modeling for congestion and pollution control: A variational inequality approach

    Science.gov (United States)

    Ramanujam, Padma

    1999-08-01

    Public concern over the state of the environment has grown over the past decade. All indications are that this concern will continue to influence policy making into the foreseeable future. Road transport is seen as the major contributor to environmental degradation. Transportation planners around the world face the question: cleaner air and/or faster commutes? While individual vehicles can be made more environmentally friendly, the sheer scale of growth in world-wide vehicle numbers is projected to cause significant environmental degradation in the longer run, and in the absence of newer and stricter polices. It is a challenge for governments to find policies that ensure congestion-free metropolitan areas while guaranteeing both critical environmental quality levels and a sufficient infrastructure access to all groups involved. The objective of the dissertation is to provide a mathematical framework to study transportation policy models for the purpose of controlling congestion and pollution. Towards this objective. a series of transportation policy models are developed to study travel behavior and to quantity the reductions in congestion and automobile emissions. The dissertation begins with a brief historical overview of some of the pioneering works in urban transportation economics and later presents the theoretical foundation for the transportation policy models developed. The dissertation introduces single modal and multimodal transportation network policy models that accomplish road pricing with the imposition of goal targets on link loads. as well as, integrated traffic equilibrium models with marketable mobile emission permits. Furthermore, equilibrium conditions are derived for each model, and both qualitative analysis and computational procedures are studied. Finally, the dissertation concludes with a comparative study of the relationship between regulatory pricing models and marketable emission permit transportation models and a discussion on key factors

  8. Ionic screening of charged impurities in electrolytically gated graphene: A partially linearized Poisson-Boltzmann model.

    Science.gov (United States)

    Sharma, P; Mišković, Z L

    2015-10-07

    We present a model describing the electrostatic interactions across a structure that consists of a single layer of graphene with large area, lying above an oxide substrate of finite thickness, with its surface exposed to a thick layer of liquid electrolyte containing salt ions. Our goal is to analyze the co-operative screening of the potential fluctuation in a doped graphene due to randomness in the positions of fixed charged impurities in the oxide by the charge carriers in graphene and by the mobile ions in the diffuse layer of the electrolyte. In order to account for a possibly large potential drop in the diffuse later that may arise in an electrolytically gated graphene, we use a partially linearized Poisson-Boltzmann (PB) model of the electrolyte, in which we solve a fully nonlinear PB equation for the surface average of the potential in one dimension, whereas the lateral fluctuations of the potential in graphene are tackled by linearizing the PB equation about the average potential. In this way, we are able to describe the regime of equilibrium doping of graphene to large densities for arbitrary values of the ion concentration without restrictions to the potential drop in the electrolyte. We evaluate the electrostatic Green's function for the partially linearized PB model, which is used to express the screening contributions of the graphene layer and the nearby electrolyte by means of an effective dielectric function. We find that, while the screened potential of a single charged impurity at large in-graphene distances exhibits a strong dependence on the ion concentration in the electrolyte and on the doping density in graphene, in the case of a spatially correlated two-dimensional ensemble of impurities, this dependence is largely suppressed in the autocovariance of the fluctuating potential.

  9. A model for screening and prioritizing consumer nanoproduct risks: A case study from South Africa.

    Science.gov (United States)

    Musee, Ndeke

    2017-03-01

    The potential risks of the increasing variety and volume of engineered nanomaterials (ENMs) entering into the ecosystem remain poorly quantified. In recent years, information essential to evaluate the ecological risks of ENMs has increased. However, the data are highly fragmented, limited, or severely lacking. This limits the usefulness of the information to support holistic screening and prioritization of potentially harmful ENMs. To screen and prioritize ENMs risks, we adopted a two-phased approach. First, a holistic framework model was developed to integrate a diverse set of factors aimed to assess the potential hazard, exposure, and in turn, risk to the ecosystem of ENMs from a given consumer nanoproduct. Secondly, using published literature we created a database of consumer nanoproduct categories, and types based on embedded ENMs type. The database consisted of eight consumer product categories, eleven different types of ENMs, and twenty-three nanoproduct types. The model results indicates the largest quantities of ENMs were released from sunscreens, textiles, cosmetics and paints with dominant ENMs quantities in descending order (based on quantity) as nTiO 2 >nZnO>nSiO 2 >nAg, and nFe 2 O 3 . In addition, according to the results from this study, nAg from washing machine were found to likely the highest risk to the environment. Overall, our model-derived results based on the case study illustrated: (i) the holistic framework's ability to screen, prioritize, rank, and compare ENMs potential exposure and risks among different nanoproducts categories and types, (ii) the derived risk estimations could support nanowastes classification with likelihood of non-uniformity of nanowastes classes even from the same nanoproduct category (e.g. cosmetics), and (iii) the lack of a mass-based criteria specific for EMNs impedes realistic exposure and risk evaluation in the ecological systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. On Regional Modeling to Support Air Quality Policies (book chapter)

    Science.gov (United States)

    We examine the use of the Community Multiscale Air Quality (CMAQ) model in simulating the changes in the extreme values of air quality that are of interest to the regulatory agencies. Year-to-year changes in ozone air quality are attributable to variations in the prevailing meteo...

  11. Models of economic geography : dynamics, estimation and policy evaluation

    NARCIS (Netherlands)

    Knaap, Thijs

    2004-01-01

    In this thesis we look at economic geography models from a number of angles. We started by placing the theory in a context of preceding theories, both earlier work on spatial economics and other children of the monopolistic competition ‘revolution.’ Next, we looked at the theoretical properties of

  12. Fiscal and Monetary Policy in a General Equilibrium Model,

    Science.gov (United States)

    1984-01-27

    Costs in Financial Assets It would be desirable from the point of view of realism to include transactions costs in security trades. Doing so would...November), pp. 545-566. Diamond, Peter (1965), "National Debt in a Neoclassical Growth Model," American Economic Review, 55 (December), pp. 1126-1150

  13. General equilibrium basic needs policy model, (updating part).

    OpenAIRE

    Kouwenaar A

    1985-01-01

    ILO pub-WEP pub-PREALC pub. Working paper, econometric model for the assessment of structural change affecting development planning for basic needs satisfaction in Ecuador - considers population growth, family size (households), labour force participation, labour supply, wages, income distribution, profit rates, capital ownership, etc.; examines nutrition, education and health as factors influencing productivity. Diagram, graph, references, statistical tables.

  14. Effect of HPV vaccination and cervical cancer screening in England by ethnicity: a modelling study.

    Science.gov (United States)

    Johnson, Helen C; Lafferty, Erin I; Eggo, Rosalind M; Louie, Karly; Soldan, Kate; Waller, Jo; Edmunds, W John

    2018-01-01

    Health equality is increasingly being considered alongside overall health gain when assessing public health interventions. However, the trade-off between the direct effects of vaccination and herd immunity could lead to unintuitive consequences for the distribution of disease burden within a population. We used a transmission dynamic model of human papillomavirus (HPV) to investigate the effect of ethnic disparities in vaccine and cervical screening uptake on inequality in disease incidence in England. We developed an individual-based model of HPV transmission and disease, parameterising it with the latest data for sexual behaviour (from National Survey of Sexual Attitudes and Lifestyles [Natsal-3]) and vaccine and screening uptake by ethnicity (from Public Health England [PHE]) and fitting it to data for HPV prevalence (from ARTISTIC, PHE, Natsal-3) and HPV-related disease incidence (from National Cancer Registry [ONS]). The outcome of interest was the age-adjusted incidence of HPV-related cancer (both cervical and non-cervical) in all women in England in view of differences and changes in vaccination and screening uptake by ethnicity in England, over time. We also studied three potential public health interventions aimed at reducing inequality in HPV-related disease incidence: increasing uptake in black and Asian females to match that in whites for vaccination; cervical screening in women who turn 25 in 2018 or later; and cervical screening in all ages. In the pre-vaccination era, before 2008, women from ethnic minorities in England reported a disproportionate share of cervical disease. Our model suggests that Asian women were 1·7 times (95% credibility interval [CI] 1·1-2·7) more likely to be diagnosed with cervical cancer than white women (22·8 vs 13·4 cases per 100 000 women). Because HPV vaccination uptake is lower in ethnic minorities, we predict an initial widening of this gap, with cervical cancer incidence in Asian women up to 2·5 times higher (95

  15. Introduction of Energy and Climate Mitigation Policy Issues in Energy - Environment Model of Latvia

    Science.gov (United States)

    Klavs, G.; Rekis, J.

    2016-12-01

    The present research is aimed at contributing to the Latvian national climate policy development by projecting total GHG emissions up to 2030, by evaluating the GHG emission reduction path in the non-ETS sector at different targets set for emissions reduction and by evaluating the obtained results within the context of the obligations defined by the EU 2030 policy framework for climate and energy. The method used in the research was bottom-up, linear programming optimisation model MARKAL code adapted as the MARKAL-Latvia model with improvements for perfecting the integrated assessment of climate policy. The modelling results in the baseline scenario, reflecting national economic development forecasts and comprising the existing GHG emissions reduction policies and measures, show that in 2030 emissions will increase by 19.1 % compared to 2005. GHG emissions stabilisation and reduction in 2030, compared to 2005, were researched in respective alternative scenarios. Detailed modelling and analysis of the Latvian situation according to the scenario of non-ETS sector GHG emissions stabilisation and reduction in 2030 compared to 2005 have revealed that to implement a cost effective strategy of GHG emissions reduction first of all a policy should be developed that ensures effective absorption of the available energy efficiency potential in all consumer sectors. The next group of emissions reduction measures includes all non-ETS sectors (industry, services, agriculture, transport, and waste management).

  16. Freshwater Ecosystem Services in Mining Regions: Modelling Options for Policy Development Support

    Directory of Open Access Journals (Sweden)

    Daniel Mercado-Garcia

    2018-04-01

    Full Text Available The ecosystem services (ES approach offers an integrated perspective of social-ecological systems, suitable for holistic assessments of mining impacts. Yet for ES models to be policy-relevant, methodological consensus in mining contexts is needed. We review articles assessing ES in mining areas focusing on freshwater components and policy support potential. Twenty-six articles were analysed concerning (i methodological complexity (data types, number of parameters, processes and ecosystem–human integration level and (ii potential applicability for policy development (communication of uncertainties, scenario simulation, stakeholder participation and management recommendations. Articles illustrate mining impacts on ES through valuation exercises mostly. However, the lack of ground- and surface-water measurements, as well as insufficient representation of the connectivity among soil, water and humans, leave room for improvements. Inclusion of mining-specific environmental stressors models, increasing resolution of topographies, determination of baseline ES patterns and inclusion of multi-stakeholder perspectives are advantageous for policy support. We argue that achieving more holistic assessments exhorts practitioners to aim for high social-ecological connectivity using mechanistic models where possible and using inductive methods only where necessary. Due to data constraints, cause–effect networks might be the most feasible and best solution. Thus, a policy-oriented framework is proposed, in which data science is directed to environmental modelling for analysis of mining impacts on water ES.

  17. Policy Model of Sustainable Infrastructure Development (Case Study : Bandarlampung City, Indonesia)

    Science.gov (United States)

    Persada, C.; Sitorus, S. R. P.; Marimin; Djakapermana, R. D.

    2018-03-01

    Infrastructure development does not only affect the economic aspect, but also social and environmental, those are the main dimensions of sustainable development. Many aspects and actors involved in urban infrastructure development requires a comprehensive and integrated policy towards sustainability. Therefore, it is necessary to formulate an infrastructure development policy that considers various dimensions of sustainable development. The main objective of this research is to formulate policy of sustainable infrastructure development. In this research, urban infrastructure covers transportation, water systems (drinking water, storm water, wastewater), green open spaces and solid waste. This research was conducted in Bandarlampung City. This study use a comprehensive modeling, namely the Multi Dimensional Scaling (MDS) with Rapid Appraisal of Infrastructure (Rapinfra), it uses of Analytic Network Process (ANP) and it uses system dynamics model. The findings of the MDS analysis showed that the status of Bandarlampung City infrastructure sustainability is less sustainable. The ANP analysis produces 8 main indicators of the most influential in the development of sustainable infrastructure. The system dynamics model offered 4 scenarios of sustainable urban infrastructure policy model. The best scenario was implemented into 3 policies consist of: the integrated infrastructure management, the population control, and the local economy development.

  18. Computer-Aided Evaluation of Screening Mammograms Based on Local Texture Models

    Czech Academy of Sciences Publication Activity Database

    Grim, Jiří; Somol, Petr; Haindl, Michal; Daneš, J.

    2009-01-01

    Roč. 18, č. 4 (2009), s. 765-773 ISSN 1057-7149 R&D Projects: GA ČR GA102/07/1594; GA ČR GA102/08/0593; GA MŠk 1M0572 Grant - others:GA MŠk(CZ) 2C06019 Institutional research plan: CEZ:AV0Z10750506 Keywords : Screening mammography * texture information * local statistical model * Gaussian mixture Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 2.848, year: 2009

  19. Uncle Tony's computer: order-of-magnitude modelling as a screening tool in environmental analysis

    CSIR Research Space (South Africa)

    Scholes, RJ

    2002-09-01

    Full Text Available : order-of-magnitude modelling as a screening tool in environmental analysis R.J. Scholes Introduction When Tony Starfield took up his position at the University of Minnesota, he wanted to stay in contact with his young nephews in South Africa... study. The method assumes a good, but not highly quantitative, knowledge of the system, and does not apply to cumulative effects. *CSIR Environmentek, P.O. Box 395, Pretoria 0001, South Africa. E-mail: bscholes@csir.co.za. production sources or loss...

  20. Experimental validation of a phase screen propagation model for nanosecond laser pulses travelling through turbulent atmospheres

    Science.gov (United States)

    Burgess, Christopher; Westgate, Christopher

    2017-10-01

    Applications involving the outdoor use of pulsed lasers systems can be affected by atmospheric turbulence and scintillation. In particular, deterministic prediction of the risk of injury or damage due to pulsed laser radiation can be difficult due to uncertainty over the focal plane fluence of radiation that has traversed through a turbulent medium. In this study, focussed beam profiles of nanosecond laser pulses are recorded for visible laser pulses that have traversed 1400m paths through turbulent atmospheres. Beam profiles are also taken under laboratory conditions. These pulses are characterised in terms of their peak focal plane fluence, total collected energy and Strehl ratio. Measured pulses are then compared statistically to pulse profiles generated by a two-dimensional phase screen propagation model based on the Von Karman power spectrum distribution. The model takes into account the refractive index structure constant (𝐶𝑛2), the wavelength, the path geometry and macroscopic beam steering. Analysis shows good correlation between the measured and simulated data, inferring that the Von Karman phase screen model can be used to predict focal plane fluence distributions for outdoor applications.

  1. QSAR Models for Thyroperoxidase Inhibition and Screening of U.S. and EU Chemical Inventories

    DEFF Research Database (Denmark)

    Abildgaard Rosenberg, Sine; D. Watt, Eric; Judson, Richard S.

    2017-01-01

    of QSAR2 identified the ten most discriminating structural features for TPO inhibition and non-inhibition, respectively. Both models were used to screen 72,524 REACH substances and 32,197 U.S. EPA substances, and QSAR2 with the expanded training set had an approximately 10% larger coverages compared...... developed two global quantitative structure-activity relationship (QSAR) models for TPO inhibition in vitro. Rigorous cross- and blinded external validations demonstrated that the first model, QSAR1, built from a training set of 877 chemicals, was robust and highly predictive with balanced accuracies of 80......Thyroperoxidase (TPO) is the enzyme that synthesizes thyroid hormones (THs). TPO inhibition by chemicals can result in decreased TH levels and developmental neurotoxicity, and therefore identification of TPO inhibition is of high relevance in safety evaluation of chemicals. In the present study, we...

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

    International Nuclear Information System (INIS)

    Zhao, Xufeng; Qian, Cunhua; Nakagawa, Toshio

    2013-01-01

    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.

  3. Credible baseline analysis for multi-model public policy studies

    Energy Technology Data Exchange (ETDEWEB)

    Parikh, S.C.; Gass, S.I.

    1981-01-01

    The nature of public decision-making and resource allocation is such that many complex interactions can best be examined and understood by quantitative analysis. Most organizations do not possess the totality of models and needed analytical skills to perform detailed and systematic quantitative analysis. Hence, the need for coordinated, multi-organization studies that support public decision-making has grown in recent years. This trend is expected not only to continue, but to increase. This paper describes the authors' views on the process of multi-model analysis based on their participation in an analytical exercise, the ORNL/MITRE Study. One of the authors was the exercise coordinator. During the study, the authors were concerned with the issue of measuring and conveying credibility of the analysis. This work led them to identify several key determinants, described in this paper, that could be used to develop a rating of credibility.

  4. Biofuel market and carbon modeling to evaluate French biofuel policy

    International Nuclear Information System (INIS)

    Bernard, F.; Prieur, A.

    2006-10-01

    In order to comply with European objectives, France has set up an ambitious biofuel plan. This plan is evaluated considering two criteria: tax exemption need and GHG emission savings. An economic marginal analysis and a life cycle assessment (LCA) are provided using a coupling procedure between a partial agro-industrial equilibrium model and a refining optimization model. Thus, we are able to determine the minimum tax exemption needed to place on the market a targeted quantity of biofuel by deducing the agro-industrial marginal cost of biofuel production to the biofuel refining long-run marginal revenue. In parallel, a biofuels LCA is carried out using model outputs. Such a method avoid common allocation problems between joint products. The French biofuel plan is evaluated for 2008, 2010 and 2012 using prospective scenarios. Results suggest that biofuel competitiveness depends on crude oil prices and petroleum products demands. Consequently, biofuel tax exemption does not always appear to be necessary. LCA results show that biofuels production and use, from 'seed to wheel', would facilitate the French Government's to compliance with its 'Plan Climat' objectives by reducing up to 5% GHG emissions in the French road transport sector by 2010. (authors)

  5. Effect of the one-child policy on influenza transmission in China: a stochastic transmission model.

    Directory of Open Access Journals (Sweden)

    Fengchen Liu

    Full Text Available BACKGROUND: China's one-child-per-couple policy, introduced in 1979, led to profound demographic changes for nearly a quarter of the world's population. Several decades later, the consequences include decreased fertility rates, population aging, decreased household sizes, changes in family structure, and imbalanced sex ratios. The epidemiology of communicable diseases may have been affected by these changes since the transmission dynamics of infectious diseases depend on demographic characteristics of the population. Of particular interest is influenza because China and Southeast Asia lie at the center of a global transmission network of influenza. Moreover, changes in household structure may affect influenza transmission. Is it possible that the pronounced demographic changes that have occurred in China have affected influenza transmission? METHODS AND FINDINGS: To address this question, we developed a continuous-time, stochastic, individual-based simulation model for influenza transmission. With this model, we simulated 30 years of influenza transmission and compared influenza transmission rates in populations with and without the one-child policy control. We found that the average annual attack rate is reduced by 6.08% (SD 2.21% in the presence of the one-child policy compared to a population in which no demographic changes occurred. There was no discernible difference in the secondary attack rate, -0.15% (SD 1.85%, between the populations with and without a one-child policy. We also forecasted influenza transmission over a ten-year time period in a population with a two-child policy under a hypothesis that a two-child-per-couple policy will be carried out in 2015, and found a negligible difference in the average annual attack rate compared to the population with the one-child policy. CONCLUSIONS: This study found that the average annual attack rate is slightly lowered in a population with a one-child policy, which may have resulted from a

  6. Effect of the one-child policy on influenza transmission in China: a stochastic transmission model.

    Science.gov (United States)

    Liu, Fengchen; Enanoria, Wayne T A; Ray, Kathryn J; Coffee, Megan P; Gordon, Aubree; Aragón, Tomás J; Yu, Guowei; Cowling, Benjamin J; Porco, Travis C

    2014-01-01

    China's one-child-per-couple policy, introduced in 1979, led to profound demographic changes for nearly a quarter of the world's population. Several decades later, the consequences include decreased fertility rates, population aging, decreased household sizes, changes in family structure, and imbalanced sex ratios. The epidemiology of communicable diseases may have been affected by these changes since the transmission dynamics of infectious diseases depend on demographic characteristics of the population. Of particular interest is influenza because China and Southeast Asia lie at the center of a global transmission network of influenza. Moreover, changes in household structure may affect influenza transmission. Is it possible that the pronounced demographic changes that have occurred in China have affected influenza transmission? To address this question, we developed a continuous-time, stochastic, individual-based simulation model for influenza transmission. With this model, we simulated 30 years of influenza transmission and compared influenza transmission rates in populations with and without the one-child policy control. We found that the average annual attack rate is reduced by 6.08% (SD 2.21%) in the presence of the one-child policy compared to a population in which no demographic changes occurred. There was no discernible difference in the secondary attack rate, -0.15% (SD 1.85%), between the populations with and without a one-child policy. We also forecasted influenza transmission over a ten-year time period in a population with a two-child policy under a hypothesis that a two-child-per-couple policy will be carried out in 2015, and found a negligible difference in the average annual attack rate compared to the population with the one-child policy. This study found that the average annual attack rate is slightly lowered in a population with a one-child policy, which may have resulted from a decrease in household size and the proportion of children in the

  7. Long term modelling in a second rank world: application to climate policies

    International Nuclear Information System (INIS)

    Crassous, R.

    2008-11-01

    This research aims at the identification of the dissatisfaction reasons with respect to the existing climate models, at the design of an innovating modelling architecture which would respond to these dissatisfactions, and at proposing climate policy assessment pathways. The authors gives a critique assessment of the modelling activity within the field of climate policies, outlines the fact that the large number and the scattering of existing long term scenarios hides a weak control of uncertainties and of the inner consistency of the produced paths, as well as the very low number of modelling paradigms. After a deepened analysis of modelling practices, the author presents the IMACLIM-R modelling architecture which is presented on a world scale and includes 12 areas and 12 sectors, and allows the simulation of evolutions by 2050, and even 2100, with a one-year time step. The author describes a scenario without any climate policy, highlights reassessment possibilities for economical trajectories which would allow greenhouse gas concentration stabilisation on a long term basis through the application of IMACLIM-R innovations. He outlines adjustment and refinement possibilities for climate policies which would robustly limit the transition cost risks

  8. A structural dynamic factor model for the effects of monetary policy estimated by the EM algorithm

    DEFF Research Database (Denmark)

    Bork, Lasse

    This paper applies the maximum likelihood based EM algorithm to a large-dimensional factor analysis of US monetary policy. Specifically, economy-wide effects of shocks to the US federal funds rate are estimated in a structural dynamic factor model in which 100+ US macroeconomic and financial time...... as opposed to the orthogonal factors resulting from the popular principal component approach to structural factor models. Correlated factors are economically more sensible and important for a richer monetary policy transmission mechanism. Secondly, I consider both static factor loadings as well as dynamic...

  9. Application of Imprecise Decision Modeling for Regional Development Policies in Indonesia

    Directory of Open Access Journals (Sweden)

    Novita Erlinda

    2016-06-01

    Full Text Available Regional Development encompasses many aspect of economic, social, and environmental attributes. In the context of developing country, the decision to fulfill these attributes are often hindered by lack of clear development scenarios and constraints. This study is an attempt to capture the complexity of decision makers for regional development scenarios using imprecise decision modeling (IDM by incorporating imprecise information and uncertainties. A series of social, economic and environmental criteria based on agreement from multi stakeholders dialogues were developed along with four policy development scenarios. Results from such a modeling provides variety of decision alternatives based on probabilities and risk assessment associated with achieving policy objectives.

  10. Managing misaligned paternity findings in research including sickle cell disease screening in Kenya: 'consulting communities' to inform policy.

    Science.gov (United States)

    Marsh, Vicki; Kombe, Francis; Fitzpatrick, Ray; Molyneux, Sassy; Parker, Michael

    2013-11-01

    The management of misaligned paternity findings raises important controversy worldwide. It has mainly, however, been discussed in the context of high-income countries. Genetic and genomics research, with the potential to show misaligned paternity, are becoming increasingly common in Africa. During a genomics study in Kenya, a dilemma arose over testing and sharing information on paternal sickle cell disease status. This dilemma may be paradigmatic of challenges in sharing misaligned paternity findings in many research and health care settings. Using a deliberative approach to community consultation to inform research practice, we explored residents' views on paternal testing and sharing misaligned paternity information. Between December 2009 and November 2010, 63 residents in Kilifi County were engaged in informed deliberative small group discussions, structured to support normative reflection within the groups, with purposive selection to explore diversity. Analysis was based on a modified framework analysis approach, drawing on relevant social science and bioethics literature. The methods generated in-depth individual and group reflection on morally important issues and uncovered wide diversity in views and values. Fundamental and conflicting values emerged around the importance of family interests and openness, underpinned by disagreement on the moral implications of marital infidelity and withholding truth. Wider consideration of ethical issues emerging in these debates supports locally-held reasoning that paternal sickle cell testing should not be undertaken in this context, in contrast to views that testing should be done with or without the disclosure of misaligned paternity information. The findings highlight the importance of facilitating wider testing of family members of affected children, contingent on the development and implementation of national policies for the management of this inherited disorder. Their richness also illustrates the potential for

  11. Reducing US cardiovascular disease burden and disparities through national and targeted dietary policies: A modelling study.

    Directory of Open Access Journals (Sweden)

    Jonathan Pearson-Stuttard

    2017-06-01

    Full Text Available Large socio-economic disparities exist in US dietary habits and cardiovascular disease (CVD mortality. While economic incentives have demonstrated success in improving dietary choices, the quantitative impact of different dietary policies on CVD disparities is not well established. We aimed to quantify and compare the potential effects on total CVD mortality and disparities of specific dietary policies to increase fruit and vegetable (F&V consumption and reduce sugar-sweetened beverage (SSB consumption in the US.Using the US IMPACT Food Policy Model and probabilistic sensitivity analyses, we estimated and compared the reductions in CVD mortality and socio-economic disparities in the US population potentially achievable from 2015 to 2030 with specific dietary policy scenarios: (a a national mass media campaign (MMC aimed to increase consumption of F&Vs and reduce consumption of SSBs, (b a national fiscal policy to tax SSBs to increase prices by 10%, (c a national fiscal policy to subsidise F&Vs to reduce prices by 10%, and (d a targeted policy to subsidise F&Vs to reduce prices by 30% among Supplemental Nutrition Assistance Program (SNAP participants only. We also evaluated a combined policy approach, combining all of the above policies. Data sources included the Surveillance, Epidemiology, and End Results Program, National Vital Statistics System, National Health and Nutrition Examination Survey, and published meta-analyses. Among the individual policy scenarios, a national 10% F&V subsidy was projected to be most beneficial, potentially resulting in approximately 150,500 (95% uncertainty interval [UI] 141,400-158,500 CVD deaths prevented or postponed (DPPs by 2030 in the US. This far exceeds the approximately 35,100 (95% UI 31,700-37,500 DPPs potentially attributable to a 30% F&V subsidy targeting SNAP participants, the approximately 25,800 (95% UI 24,300-28,500 DPPs for a 1-y MMC, or the approximately 31,000 (95% UI 26,800-35,300 DPPs for a 10

  12. The Effect of Treatment Advances on the Mortality Results of Breast Cancer Screening Trials: A Microsimulation Model.

    Science.gov (United States)

    Birnbaum, Jeanette; Gadi, Vijayakrishna K; Markowitz, Elan; Etzioni, Ruth

    2016-02-16

    Mammography trials, which are the primary sources of evidence for screening benefit, were conducted decades ago. Whether advances in systemic therapies have rendered previously observed benefits of screening less significant is unknown. To compare the outcomes of breast cancer screening trials had they been conducted using contemporary systemic treatments with outcomes of trials conducted with previously used treatments. Computer simulation model of 3 virtual screening trials with similar reductions in advanced-stage cancer cases but reflecting treatment patterns in 1975 (prechemotherapy era), 1999, or 2015 (treatment according to receptor status). Meta-analyses of screening and treatment trials; study of dissemination of primary systemic treatments; SEER (Surveillance, Epidemiology, and End Results) registry. U.S. women aged 50 to 74 years. 10 and 25 years. Population. Mammography, chemotherapy, tamoxifen, aromatase inhibitors, and trastuzumab. Breast cancer mortality rate ratio (MRR) and absolute risk reduction (ARR) obtained by the difference in cumulative breast cancer mortality between control and screening groups. At 10 years, screening in a 1975 trial yielded an MRR of 90% and an ARR of 5 deaths per 10,000 women. A 2015 screening trial yielded a 10-year MRR of 90% and an ARR of 3 deaths per 10,000 women. Greater reductions in advanced-stage disease yielded a greater screening effect, but MRRs remained similar across trials. However, ARRs were consistently lower under contemporary treatments. When contemporary treatments were available only for early-stage cases, the MRR was 88%. Disease models simplify reality and cannot capture all breast cancer subtypes. Advances in systemic therapies for breast cancer have not substantively reduced the relative benefits of screening but have likely reduced the absolute benefits because of their positive effect on breast cancer survival. University of Washington and National Cancer Institute.

  13. Dynamic formulation of a top-down and bottom-up merging energy policy model

    International Nuclear Information System (INIS)

    Frei, Christoph W.; Haldi, P.-A.; Sarlos, G.Gerard

    2003-01-01

    The impact of energy policy measures is not restricted to the energy system and should therefore be analysed within an economy-wide framework, while keeping the essential details of the energy sector. The aim of this paper is to present new developments in the field of the consistent evaluation of indicators for the sustainability assessment of energy policy measures. Starting from the static concept of Boehringer (Energy Econ. 20 (1998) 233), this paper shows how the complementarity format can be used in computable general equilibrium (CGE) modelling for a dynamic formulation of bottom-up and top-down approach merging models. While a hybrid approach increases the credibility of CGE models in energy policy analysis by replacing the energy sector generic functional forms with a bottom-up activity analysis based on specific technologies, the endogenous formulation of investment decisions makes an explicit description of evolving specific capital stocks and technology mixes possible. Both features are essential when assessing effects of policy measures that may be affected by structural change--which is typically the case in the long-term assessment of energy policy measures

  14. Debates—Perspectives on socio-hydrology: Modeling flood risk as a public policy problem

    Science.gov (United States)

    Gober, Patricia; Wheater, Howard S.

    2015-06-01

    Socio-hydrology views human activities as endogenous to water system dynamics; it is the interaction between human and biophysical processes that threatens the viability of current water systems through positive feedbacks and unintended consequences. Di Baldassarre et al. implement socio-hydrology as a flood risk problem using the concept of social memory as a vehicle to link human perceptions to flood damage. Their mathematical model has heuristic value in comparing potential flood damages in green versus technological societies. It can also support communities in exploring the potential consequences of policy decisions and evaluating critical policy tradeoffs, for example, between flood protection and economic development. The concept of social memory does not, however, adequately capture the social processes whereby public perceptions are translated into policy action, including the pivotal role played by the media in intensifying or attenuating perceived flood risk, the success of policy entrepreneurs in keeping flood hazard on the public agenda during short windows of opportunity for policy action, and different societal approaches to managing flood risk that derive from cultural values and economic interests. We endorse the value of seeking to capture these dynamics in a simplified conceptual framework, but favor a broader conceptualization of socio-hydrology that includes a knowledge exchange component, including the way modeling insights and scientific results are communicated to floodplain managers. The social processes used to disseminate the products of socio-hydrological research are as important as the research results themselves in determining whether modeling is used for real-world decision making.

  15. Combination of Biological Screening in a Cellular Model of Viral Latency and Virtual Screening Identifies Novel Compounds That Reactivate HIV-1

    Science.gov (United States)

    Gallastegui, Edurne; Marshall, Brett; Vidal, David; Sanchez-Duffhues, Gonzalo; Collado, Juan A.; Alvarez-Fernández, Carmen; Luque, Neus; Terme, Jean-Michel; Gatell, Josep M.; Sánchez-Palomino, Sonsoles; Muñoz, Eduardo; Mestres, Jordi; Verdin, Eric

    2012-01-01

    Although highly active antiretroviral therapy (HAART) has converted HIV into a chronic disease, a reservoir of HIV latently infected resting T cells prevents the eradication of the virus from patients. To achieve eradication, HAART must be combined with drugs that reactivate the dormant viruses. We examined this problem in an established model of HIV postintegration latency by screening a library of small molecules. Initially, we identified eight molecules that reactivated latent HIV. Using them as templates, additional hits were identified by means of similarity-based virtual screening. One of those hits, 8-methoxy-6-methylquinolin-4-ol (MMQO), proved to be useful to reactivate HIV-1 in different cellular models, especially in combination with other known reactivating agents, without causing T-cell activation and with lower toxicity than that of the initial hits. Interestingly, we have established that MMQO produces Jun N-terminal protein kinase (JNK) activation and enhances the T-cell receptor (TCR)/CD3 stimulation of HIV-1 reactivation from latency but inhibits CD3-induced interleukin-2 (IL-2) and tumor necrosis factor alpha (TNF-α) gene transcription. Moreover, MMQO prevents TCR-induced cell cycle progression and proliferation in primary T cells. The present study documents that the combination of biological screening in a cellular model of viral latency with virtual screening is useful for the identification of novel agents able to reactivate HIV-1. Moreover, we set the bases for a hypothetical therapy to reactivate latent HIV by combining MMQO with physiological or pharmacological TCR/CD3 stimulation. PMID:22258251

  16. Empowerment model for nurse leaders' participation in health policy development: an east African perspective.

    Science.gov (United States)

    Shariff, Nilufa Jivraj

    2015-01-01

    Nurses comprise the largest portion of the health care workforce in most countries; they interact closely with patients and communities, they work throughout the day and within all sectors of health care. Their breath of practice gives them a broad understanding of requirements of the health care system, of how factors in the environment affect the health outcomes of clients and communities. Nurses' involvement in health policy development ensures that health services are: safe, effective, available and inexpensive. A Delphi survey was utilized and included the following criteria: expert panelists, three iterative rounds, qualitative and quantitative analysis, and building consensus. The overall aim of the study was to develop "An Empowerment Model for Nurse Leaders' participation in Health Policy Development". The study included purposively selected sample of national nurse leaders from the three East African countries of Kenya, Tanzania and Uganda. The study was conducted in three iterative rounds. Data collection tools were questionnaires. Data analysis was done by examining the data for the most commonly occurring concepts in the first round and descriptive statistics in the second and third rounds. The findings of the study support the development of the "Empowerment Model for Nurse Leaders' Participation in Health Policy Development". Further the study identified that there was a significant gap in and barriers to participation in health policy activity and that an opportunity seems to exist to enable and develop nurse leaders' role and involvement in this respect. There was consensus on factors considered to be facilitators and barriers to nurse leaders' involvement in health policy development. Furthermore, consensus was achieved on essential leadership attributes that enhance nurse leaders' participation in health policy development. The model was validated a small sample of the nurse leaders' who participated in the study. The model provides a framework

  17. A goal programming model for environmental policy analysis: Application to Spain

    International Nuclear Information System (INIS)

    San Cristóbal, José Ramón

    2012-01-01

    Sustainable development has become an important part of international and national approaches to integrate economic, environmental, social and ethical considerations so that a good quality of life can be enjoyed by current and future generations for as long as possible. However, nowadays sustainable development is threatened by industrial pollution emissions which cause serious environmental problems. Due to a lack of adequate quantitative models for environmental policy analysis, there is a strong need for analytical models in order to know the effects of environmental policies. In the present paper, a goal programming model, based on an environmental/input–output linear programming model, is developed and applied to the Spanish economy. The model combines relations between economic, energy, social and environmental effects, providing valuable information for policy-makers in order to define and examine the different goals that must be implemented to reach sustainability. - Highlights: ► In this paper a goal programming model is developed. ► The model considers environmental, energy, social and economic goals. ► The model shows the effects of a reduction in greenhouse gasses emission and energy requirements. ► The model is applied to the Spanish economy.

  18. 12 CFR Appendix C to Part 229 - Model Availability Policy Disclosures, Clauses, and Notices; Model Substitute Check Policy...

    Science.gov (United States)

    2010-01-01

    ... OF FUNDS AND COLLECTION OF CHECKS (REGULATION CC) Pt. 229, App. C Appendix C to Part 229—Model... Checks and Your Rights— Substitute Checks and Your Rights What Is a Substitute Check? To make check... rights under other law with respect to those transactions. What Are My Rights Regarding Substitute Checks...

  19. Let's Talk About Water: Using Film Screenings to Engage Students and the Public in Water Science and Policy

    Science.gov (United States)

    Saleem Arrigo, J. A.; Berry, K.; Hooper, R. P.; Lilienfeld, L.

    2013-12-01

    "Let's Talk about Water" is a film symposium designed to bring together experts and the public to talk about the complex water issues facing society. The format of the event is quite simple: a panel of experts and the audience view a water documentary (such as "FLOW", "Liquid Assets", or "Gasland") together and there is an extended moderated discussion period following the film between the panel and the audience. Over the course of several events, we have developed best practices that make this simple format very effective. A film creates a context of subject and language for the discussion--it gets the audience and the panel on the same page. The moderators must actively manage the discussion, both challenging the panelists with follow up questions, asking questions to simplify the language the expert is using, and passing a question among panelists to bring out different points of view. The panelists are provided with the film in advance to view and, most importantly, meet the day before the event to discuss the film. This makes for a much more convivial discussion at the event. We have found that these discussions can easily be sustained for 90 to 120 minutes with active audience participation. We have found key element of the event is local relevance. Films should be carefully chosen to resonate with the audience, and the local host is critical in defining the audience, goals and identified panel members. Having local experts from universities and representatives from local water authorities and environmental groups bring a sense of community and a confidence in the audience that the panel members have local knowledge that is important for sustaining discussion. The discussion begins with points raised by the movie (are these issues real? Do they apply here? What are the scientific, engineering, and policy solutions to these problems?) and then segues into a discussion about career opportunities in the water sector, volunteer opportunities in the community or

  20. The social and political lives of zoonotic disease models: narratives, science and policy.

    Science.gov (United States)

    Leach, Melissa; Scoones, Ian

    2013-07-01

    Zoonotic diseases currently pose both major health threats and complex scientific and policy challenges, to which modelling is increasingly called to respond. In this article we argue that the challenges are best met by combining multiple models and modelling approaches that elucidate the various epidemiological, ecological and social processes at work. These models should not be understood as neutral science informing policy in a linear manner, but as having social and political lives: social, cultural and political norms and values that shape their development and which they carry and project. We develop and illustrate this argument in relation to the cases of H5N1 avian influenza and Ebola, exploring for each the range of modelling approaches deployed and the ways they have been co-constructed with a particular politics of policy. Addressing the complex, uncertain dynamics of zoonotic disease requires such social and political lives to be made explicit in approaches that aim at triangulation rather than integration, and plural and conditional rather than singular forms of policy advice. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Urban adaptation to mega-drought: Anticipatory water modeling, policy, and planning in Phoenix

    Science.gov (United States)

    Gober, P.; Sampson, D. A.; Quay, R.; White, D. D.; Chow, W.

    2016-12-01

    There is increasing interest in using the results of water models for long-term planning and policy analysis. Achieving this goal requires more effective integration of human dimensions into water modeling and a paradigm shift in the way models are developed and used. A user-defined focus argues in favor of models that are designed to foster public debate and engagement about the difficult trade-offs that are inevitable in managing complex water systems. These models also emphasize decision making under uncertainty and anticipatory planning, and are developed through a collaborative and iterative process. This paper demonstrates the use of anticipatory modeling for long-term drought planning in Phoenix, one of the largest and fastest growing urban areas in the southwestern USA. WaterSim 5, an anticipatory water policy and planning model, was used to explore groundwater sustainability outcomes for mega-drought conditions across a range of policies, including population growth management, water conservation, water banking, direct reuse of RO reclaimed water, and water augmentation. Results revealed that business-as-usual population growth, per capita use trends, and management strategies may not be sustainable over the long term, even without mega-drought conditions as years of available groundwater supply decline over the simulation period from 2000 to 2060. Adding mega-drought increases the decline in aquifer levels and increases the variability in flows and uncertainty about future groundwater supplies. Simulations that combine drought management policies can return the region to sustainable. Results demonstrate the value of long-term planning and policy analysis for anticipating and adapting to environmental change.

  2. Digital terrain modelling development and applications in a policy support environment

    CERN Document Server

    Peckham, Robert Joseph

    2007-01-01

    This publication is the first book on the development and application of digital terrain modelling for regional planning and policy support. It is a compilation of research results by international research groups at the European Commission's Joint Research Centre providing scientific support to the development and implementation of EU environmental policy. Applications include the pan-European River and Catchment Database, European Flood Alert System, European Digital Soil Database and alternative solar energy resources, all discussed in a GIS framework in the context of the INfrastructure for SPatial InfoRmation in Europe (INSPIRE). This practice-oriented book is recommended to practicing environmental modellers and GIS experts working on regional planning and policy support applications.

  3. A model rights and ownership of educational materials policy for institutions.

    Science.gov (United States)

    Audette, L G

    1980-03-01

    This paper reports a survey taken of 79 college and university medical schools seeking the status of policy formation regarding in-house created educational materials at each location. About 65% (51) of the institutions had no definitive policies, but over half of those were aware of the need. Twenty-six provided either written documents or a narrative describing how they approach the problem. Only two recognized the special area of media production. A model policy was synthesized from the aggregate. The model provides for support and recognition of creative service units and a philosophical framework upon which the entire group, including content experts, production staff, and parent institution, can share income and recognition equitably.

  4. The Brazil SimSmoke policy simulation model: the effect of strong tobacco control policies on smoking prevalence and smoking-attributable deaths in a middle income nation.

    Directory of Open Access Journals (Sweden)

    David Levy

    Full Text Available Brazil has reduced its smoking rate by about 50% in the last 20 y. During that time period, strong tobacco control policies were implemented. This paper estimates the effect of these stricter policies on smoking prevalence and associated premature mortality, and the effect that additional policies may have.The model was developed using the SimSmoke tobacco control policy model. Using policy, population, and smoking data for Brazil, the model assesses the effect on premature deaths of cigarette taxes, smoke-free air laws, mass media campaigns, marketing restrictions, packaging requirements, cessation treatment programs, and youth access restrictions. We estimate the effect of past policies relative to a counterfactual of policies kept to 1989 levels, and the effect of stricter future policies. Male and female smoking prevalence in Brazil have fallen by about half since 1989, which represents a 46% (lower and upper bounds: 28%-66% relative reduction compared to the 2010 prevalence under the counterfactual scenario of policies held to 1989 levels. Almost half of that 46% reduction is explained by price increases, 14% by smoke-free air laws, 14% by marketing restrictions, 8% by health warnings, 6% by mass media campaigns, and 10% by cessation treatment programs. As a result of the past policies, a total of almost 420,000 (260,000-715,000 deaths had been averted by 2010, increasing to almost 7 million (4.5 million-10.3 million deaths projected by 2050. Comparing future implementation of a set of stricter policies to a scenario with 2010 policies held constant, smoking prevalence by 2050 could be reduced by another 39% (29%-54%, and 1.3 million (0.9 million-2.0 million out of 9 million future premature deaths could be averted.Brazil provides one of the outstanding public health success stories in reducing deaths due to smoking, and serves as a model for other low and middle income nations. However, a set of stricter policies could further reduce

  5. Cost-effectiveness of HIV and syphilis antenatal screening: a modelling study.

    Science.gov (United States)

    Bristow, Claire C; Larson, Elysia; Anderson, Laura J; Klausner, Jeffrey D

    2016-08-01

    The WHO called for the elimination of maternal-to-child transmission (MTCT) of HIV and syphilis, a harmonised approach for the improvement of health outcomes for mothers and children. Testing early in pregnancy, treating seropositive pregnant women and preventing syphilis reinfection can prevent MTCT of HIV and syphilis. We assessed the health and economic outcomes of a dual testing strategy in a simulated cohort of 100 000 antenatal care patients in Malawi. We compared four screening algorithms: (1) HIV rapid test only, (2) dual HIV and syphilis rapid tests, (3) single rapid tests for HIV and syphilis and (4) HIV rapid and syphilis laboratory tests. We calculated the expected number of adverse pregnancy outcomes, the expected costs and the expected newborn disability-adjusted life years (DALYs) for each screening algorithm. The estimated costs and DALYs for each screening algorithm were assessed from a societal perspective using Markov progression models. Additionally, we conducted a Monte Carlo multiway sensitivity analysis, allowing for ranges of inputs. Our cohort decision model predicted the lowest number of adverse pregnancy outcomes in the dual HIV and syphilis rapid test strategy. Additionally, from the societal perspective, the costs of prevention and care using a dual HIV and syphilis rapid testing strategy was both the least costly ($226.92 per pregnancy) and resulted in the fewest DALYs (116 639) per 100 000 pregnancies. In the Monte Carlo simulation the dual HIV and syphilis algorithm was always cost saving and almost always reduced DALYs compared with HIV testing alone. The results of the cost-effectiveness analysis showed that a dual HIV and syphilis test was cost saving compared with all other screening strategies. Updating existing prevention of mother-to-child HIV transmission programmes in Malawi and similar countries to include dual rapid testing for HIV and syphilis is likely to be advantageous. Published by the BMJ Publishing Group

  6. Consumers’ evaluation of national new energy vehicle policy in China: An analysis based on a four paradigm model

    International Nuclear Information System (INIS)

    Li, Wenbo; Long, Ruyin; Chen, Hong

    2016-01-01

    The Chinese government has issued numerous policies to promote the development and adoption of new energy vehicles (NEVs) to address the problem of excessive energy consumption and environmental pollution. In this study we divided these policies into seven categories: macroscopic, demonstration, subsidization, preferential tax, technical support, industry management, and infrastructure. Since consumers’ opinions affect the policy choices of government, based on questionnaire data we use a four paradigm model to analyze the consumers’ evaluation of each policy in terms of perceptions of importance and satisfaction. The results show that macroscopic policies are perceived to be of high importance and satisfaction, whereas for industry management policies they are perceived to be of low importance and satisfaction. The importance perceptions of preferential tax and demonstration policies are low, whereas perceptions of their satisfaction are high. Perceptions of the importance of subsidization, technical support, and infrastructure policies are high, whereas perceptions of their satisfaction are low. We find that the subsidization, technical support, and infrastructure policies need urgent improvement. Finally, we put forward several suggestions to improve the current policies and increase the consumers’ intention to adopt NEVs. - Highlights: • This study divided Chinese NEV-related policies into seven types. • This study analyzed consumers’ evaluation of NEV-related policies. • Consumers’ evaluations about NEV-related policies were diverse. • Subsidization, technical support, and infrastructure policies need improvement.

  7. A Screening Model to Predict Microalgae Biomass Growth in Photobioreactors and Raceway Ponds

    Energy Technology Data Exchange (ETDEWEB)

    Huesemann, Michael H.; Van Wagenen, Jonathan M.; Miller, Tyler W.; Chavis, Aaron R.; Hobbs, Watts B.; Crowe, Braden J.

    2013-06-01

    A microalgae biomass growth model was developed for screening novel strains for their potential to exhibit high biomass productivities under nutrient-replete conditions in photobioreactors or outdoor ponds. Growth is modeled by first estimating the light attenuation by biomass according to Beer-Lambert’s law, and then calculating the specific growth rate in discretized culture volume slices that receive declining light intensities due to attenuation. The model requires only two physical and two species-specific biological input parameters, all of which are relatively easy to determine: incident light intensity, culture depth, as well as the biomass light absorption coefficient and the specific growth rate as a function of light intensity. Roux bottle culture experiments were performed with Nannochloropsis salina at constant temperature (23 °C) at six different incident light intensities (5, 10, 25, 50, 100, 250, and 850 μmol/m2∙ sec) to determine both the specific growth rate under non-shading conditions and the biomass light absorption coefficient as a function of light intensity. The model was successful in predicting the biomass growth rate in these Roux bottle cultures during the light-limited linear phase at different incident light intensities. Model predictions were moderately sensitive to minor variations in the values of input parameters. The model was also successful in predicting the growth performance of Chlorella sp. cultured in LED-lighted 800 L raceway ponds operated at constant temperature (30 °C) and constant light intensity (1650 μmol/m2∙ sec). Measurements of oxygen concentrations as a function of time demonstrated that following exposure to darkness, it takes at least 5 seconds for cells to initiate dark respiration. As a result, biomass loss due to dark respiration in the aphotic zone of a culture is unlikely to occur in highly mixed small-scale photobioreactors where cells move rapidly in and out of the light. By contrast, as

  8. A screening model to predict microalgae biomass growth in photobioreactors and raceway ponds.

    Science.gov (United States)

    Huesemann, M H; Van Wagenen, J; Miller, T; Chavis, A; Hobbs, S; Crowe, B

    2013-06-01

    A microalgae biomass growth model was developed for screening novel strains for their potential to exhibit high biomass productivities under nutrient-replete conditions in photobioreactors or outdoor ponds. Growth is modeled by first estimating the light attenuation by biomass according to Beer-Lambert's Law, and then calculating the specific growth rate in discretized culture volume slices that receive declining light intensities due to attenuation. The model uses only two physical and two species-specific biological input parameters, all of which are relatively easy to determine: incident light intensity, culture depth, as well as the biomass light absorption coefficient and the specific growth rate as a function of light intensity. Roux bottle culture experiments were performed with Nannochloropsis salina at constant temperature (23°C) at six different incident light intensities (10, 25, 50, 100, 250, and 850 µmol/m(2)  s) to determine both the specific growth rate under non-shading conditions and the biomass light absorption coefficient as a function of light intensity. The model was successful in predicting the biomass growth rate in these Roux bottle batch cultures during the light-limited linear phase at different incident light intensities. Model predictions were moderately sensitive to minor variations in the values of input parameters. The model was also successful in predicting the growth performance of Chlorella sp. cultured in LED-lighted 800 L raceway ponds operated in batch mode at constant temperature (30°C) and constant light intensity (1,650 µmol/m(2)  s). Measurements of oxygen concentrations as a function of time demonstrated that following exposure to darkness, it takes at least 5 s for cells to initiate dark respiration. As a result, biomass loss due to dark respiration in the aphotic zone of a culture is unlikely to occur in highly mixed small-scale photobioreactors where cells move rapidly in and out of the light. By contrast

  9. Semantic policy and adversarial modeling for cyber threat identification and avoidance

    Science.gov (United States)

    DeFrancesco, Anton; McQueary, Bruce

    2009-05-01

    Today's enterprise networks undergo a relentless barrage of attacks from foreign and domestic adversaries. These attacks may be perpetrated with little to no funding, but may wreck incalculable damage upon the enterprises security, network infrastructure, and services. As more services come online, systems that were once in isolation now provide information that may be combined dynamically with information from other systems to create new meaning on the fly. Security issues are compounded by the potential to aggregate individual pieces of information and infer knowledge at a higher classification than any of its constituent parts. To help alleviate these challenges, in this paper we introduce the notion of semantic policy and discuss how it's use is evolving from a robust approach to access control to preempting and combating attacks in the cyber domain, The introduction of semantic policy and adversarial modeling to network security aims to ask 'where is the network most vulnerable', 'how is the network being attacked', and 'why is the network being attacked'. The first aspect of our approach is integration of semantic policy into enterprise security to augment traditional network security with an overall awareness of policy access and violations. This awareness allows the semantic policy to look at the big picture - analyzing trends and identifying critical relations in system wide data access. The second aspect of our approach is to couple adversarial modeling with semantic policy to move beyond reactive security measures and into a proactive identification of system weaknesses and areas of vulnerability. By utilizing Bayesian-based methodologies, the enterprise wide meaning of data and semantic policy is applied to probability and high-level risk identification. This risk identification will help mitigate potential harm to enterprise networks by enabling resources to proactively isolate, lock-down, and secure systems that are most vulnerable.

  10. Including policy and management in socio-hydrology models: initial conceptualizations

    Science.gov (United States)

    Hermans, Leon; Korbee, Dorien

    2017-04-01

    Socio-hydrology studies the interactions in coupled human-water systems. So far, the use of dynamic models that capture the direct feedback between societal and hydrological systems has been dominant. What has not yet been included with any particular emphasis, is the policy or management layer, which is a central element in for instance integrated water resources management (IWRM) or adaptive delta management (ADM). Studying the direct interactions between human-water systems generates knowledges that eventually helps influence these interactions in ways that may ensure better outcomes - for society and for the health and sustainability of water systems. This influence sometimes occurs through spontaneous emergence, uncoordinated by societal agents - private sector, citizens, consumers, water users. However, the term 'management' in IWRM and ADM also implies an additional coordinated attempt through various public actors. This contribution is a call to include the policy and management dimension more prominently into the research focus of the socio-hydrology field, and offers first conceptual variables that should be considered in attempts to include this policy or management layer in socio-hydrology models. This is done by drawing on existing frameworks to study policy processes throughout both planning and implementation phases. These include frameworks such as the advocacy coalition framework, collective learning and policy arrangements, which all emphasis longer-term dynamics and feedbacks between actor coalitions in strategic planning and implementation processes. A case about longter-term dynamics in the management of the Haringvliet in the Netherlands is used to illustrate the paper.

  11. Prostitution and Human Trafficking : A model-based exploration and policy analysis

    NARCIS (Netherlands)

    Kovari, A.; Pruyt, E.

    2012-01-01

    The meeting of the oldest profession with modern slavery is the topic of this paper. After a brief introduction to prostitution and prostitution-related human trafficking, this paper focuses on the Dutch policy debate. A System Dynamics simulation model related to the Dutch situation developed to

  12. An Economic Model of Brazil’s Ethanol-Sugar Markets and Impacts of Fuel Policies

    NARCIS (Netherlands)

    Drabik, D.; Gorter, de H.; Just, D.R.; Timilsina, G.R.

    2014-01-01

    We develop an economic model of flex plants, export demands and two domestic fuel demand curves: E25, a 25 percent blend of ethanol with gasoline consumed by conventional cars, and E100, ethanol consumed only by flex cars. This allows us to analyze the market impacts of specific policies, namely the

  13. The Impact of State Legislation and Model Policies on Bullying in Schools

    Science.gov (United States)

    Terry, Amanda

    2018-01-01

    Background: The purpose of this study was to determine the impact of the coverage of state legislation and the expansiveness ratings of state model policies on the state-level prevalence of bullying in schools. Methods: The state-level prevalence of bullying in schools was based on cross-sectional data from the 2013 High School Youth Risk Behavior…

  14. International Monetary Policy Coordination in a New Keynesian Model with NICE Features

    Science.gov (United States)

    Poutineau, Jean-Christophe; Vermandel, Gauthier

    2018-01-01

    The authors provide a static two-country new Keynesian model to teach two related questions in international macroeconomics: the international transmission of unilateral monetary policy decisions and the gains coming from the coordination monetary rules. They concentrate on "normal times" and use a thoroughly graphical approach to…

  15. An Exploration of the System Dynamics Field : A Model-Based Policy Analysis

    NARCIS (Netherlands)

    Rose, A.C.

    2014-01-01

    This report presents a first look study at the field of System Dynamics. The objective of the study is to perform a model-based policy analysis in order to investigate the future advancement of the System Dynamics field. The aim of this investigation is to determine what this advancement should look

  16. Firm Size and Monetary Policy Transmission: A Theoretical Model on the Role of Capital Investment Expenditures

    NARCIS (Netherlands)

    Raabe, K.; Arnold, I.; Kool, C.J.M.

    This paper presents a dynamic investment model that explains differences in the sensitivity of small- and large-sized firms to changes in the money market interest rate. In contrast to existing studies on the firm size effects of monetary policy, the importance of firms as monetary transmission

  17. Why do we need to integrate farmer decision making and wildlife models for policy evaluation?

    DEFF Research Database (Denmark)

    Malawska, Anna Katarzyna; Topping, Christopher John; Nielsen, Helle Ørsted

    2014-01-01

    and technical limitations, traditional agricultural economic and ecological models fall short in terms of predictions of impacts of agri-environmental measures. The feedback situation between policy, human behaviour and ecological systems behaviour can confound these approaches, which do not take systems...

  18. Forces for Failure and Genocide: The Plantation Model of Urban Educational Policy Making in St. Louis

    Science.gov (United States)

    Jones, Bruce Anthony

    2005-01-01

    This article is about policy decision making and racial politics in the St. Louis, Missouri, school district. From a research standpoint, traditional policymaking models are inadequate for explaining the evolution of school reform events in St. Louis over the past year. Teachers, principals, school staff, and parents perceive themselves to be…

  19. Costs and cost effectiveness of different strategies for chlamydia screening and partner notification: an economic and mathematical modelling study.

    Science.gov (United States)

    Turner, Katy; Adams, Elisabeth; Grant, Arabella; Macleod, John; Bell, Gill; Clarke, Jan; Horner, Paddy

    2011-01-04

    To compare the cost, cost effectiveness, and sex equity of different intervention strategies within the English National Chlamydia Screening Programme. To develop a tool for calculating cost effectiveness of chlamydia control programmes at a local, national, or international level. An economic and mathematical modelling study with cost effectiveness analysis. Costs were restricted to those of screening and partner notification from the perspective of the NHS and excluded patient costs, the costs of reinfection, and costs of complications arising from initial infection. England. Population Individuals eligible for the National Chlamydia Screening Programme. Cost effectiveness of National Chlamydia Screening Programme in 2008-9 (as cost per individual tested, cost per positive diagnosis, total cost of screening, number screened, number infected, sex ratio of those tested and treated). Comparison of baseline programme with two different interventions-(i) increased coverage of primary screening in men and (ii) increased efficacy of partner notification. In 2008-9 screening was estimated to cost about £46.3m in total and £506 per infection treated. Provision for partner notification within the screening programme cost between £9 and £27 per index case, excluding treatment and testing. The model results suggest that increasing male screening coverage from 8% (baseline value) to 24% (to match female coverage) would cost an extra £22.9m and increase the cost per infection treated to £528. In contrast, increasing partner notification efficacy from 0.4 (baseline value) to 0.8 partners per index case would cost an extra £3.3m and would reduce the cost per infection diagnosed to £449. Increasing screening coverage to 24% in men would cost over six times as much as increasing partner notification to 0.8 but only treat twice as many additional infections. In the English National Chlamydia Screening Programme increasing the effectiveness of partner notification is likely

  20. Cost-Effectiveness of Enhanced Syphilis Screening among HIV-Positive Men Who Have Sex with Men: A Microsimulation Model

    Science.gov (United States)

    Tuite, Ashleigh R.; Burchell, Ann N.; Fisman, David N.

    2014-01-01

    Background Syphilis co-infection risk has increased substantially among HIV-infected men who have sex with men (MSM). Frequent screening for syphilis and treatment of men who test positive might be a practical means of controlling the risk of infection and disease sequelae in this population. Purpose We evaluated the cost-effectiveness of strategies that increased the frequency and population coverage of syphilis screening in HIV-infected MSM receiving HIV care, relative to current standard of care. Methods We developed a state-transition microsimulation model of syphilis natural history and medical care in HIV-infected MSM receiving care for HIV. We performed Monte Carlo simulations using input data derived from a large observational cohort in Ontario, Canada, and from published biomedical literature. Simulations compared usual care (57% of the population screened annually) to different combinations of more frequent (3- or 6-monthly) screening and higher coverage (100% screened). We estimated expected disease-specific outcomes, quality-adjusted survival, costs, and cost-effectiveness associated with each strategy from the perspective of a public health care payer. Results Usual care was more costly and less effective than strategies with more frequent or higher coverage screening. Higher coverage strategies (with screening frequency of 3 or 6 months) were expected to be cost-effective based on usually cited willingness-to-pay thresholds. These findings were robust in the face of probabilistic sensitivity analyses, alternate cost-effectiveness thresholds, and alternate assumptions about duration of risk, program characteristics, and management of underlying HIV. Conclusions We project that higher coverage and more frequent syphilis screening of HIV-infected MSM would be a highly cost-effective health intervention, with many potentially viable screening strategies projected to both save costs and improve health when compared to usual care. The baseline requirement

  1. Cost-effectiveness of enhanced syphilis screening among HIV-positive men who have sex with men: a microsimulation model.

    Directory of Open Access Journals (Sweden)

    Ashleigh R Tuite

    Full Text Available Syphilis co-infection risk has increased substantially among HIV-infected men who have sex with men (MSM. Frequent screening for syphilis and treatment of men who test positive might be a practical means of controlling the risk of infection and disease sequelae in this population.We evaluated the cost-effectiveness of strategies that increased the frequency and population coverage of syphilis screening in HIV-infected MSM receiving HIV care, relative to current standard of care.We developed a state-transition microsimulation model of syphilis natural history and medical care in HIV-infected MSM receiving care for HIV. We performed Monte Carlo simulations using input data derived from a large observational cohort in Ontario, Canada, and from published biomedical literature. Simulations compared usual care (57% of the population screened annually to different combinations of more frequent (3- or 6-monthly screening and higher coverage (100% screened. We estimated expected disease-specific outcomes, quality-adjusted survival, costs, and cost-effectiveness associated with each strategy from the perspective of a public health care payer.Usual care was more costly and less effective than strategies with more frequent or higher coverage screening. Higher coverage strategies (with screening frequency of 3 or 6 months were expected to be cost-effective based on usually cited willingness-to-pay thresholds. These findings were robust in the face of probabilistic sensitivity analyses, alternate cost-effectiveness thresholds, and alternate assumptions about duration of risk, program characteristics, and management of underlying HIV.We project that higher coverage and more frequent syphilis screening of HIV-infected MSM would be a highly cost-effective health intervention, with many potentially viable screening strategies projected to both save costs and improve health when compared to usual care. The baseline requirement for regular blood testing in this

  2. In silico screening of estrogen-like chemicals based on different nonlinear classification models.

    Science.gov (United States)

    Liu, Huanxiang; Papa, Ester; Walker, John D; Gramatica, Paola

    2007-07-01

    Increasing concern is being shown by the scientific community, government regulators, and the public about endocrine-disrupting chemicals that are adversely affecting human and wildlife health through a variety of mechanisms. There is a great need for an effective means of rapidly assessing endocrine-disrupting activity, especially estrogen-simulating activity, because of the large number of such chemicals in the environment. In this study, quantitative structure activity relationship (QSAR) models were developed to quickly and effectively identify possible estrogen-like chemicals based on 232 structurally-diverse chemicals (training set) by using several nonlinear classification methodologies (least-square support vector machine (LS-SVM), counter-propagation artificial neural network (CP-ANN), and k nearest neighbour (kNN)) based on molecular structural descriptors. The models were externally validated by 87 chemicals (prediction set) not included in the training set. All three methods can give satisfactory prediction results both for training and prediction sets, and the most accurate model was obtained by the LS-SVM approach through the comparison of performance. In addition, our model was also applied to about 58,000 discrete organic chemicals; about 76% were predicted not to bind to Estrogen Receptor. The obtained results indicate that the proposed QSAR models are robust, widely applicable and could provide a feasible and practical tool for the rapid screening of potential estrogens.

  3. Construction of protein profile classification model and screening of proteomic signature of acute leukemia.

    Science.gov (United States)

    Xu, Yun; Zhuo, Jiacai; Duan, Yonggang; Shi, Benhang; Chen, Xuhong; Zhang, Xiaoli; Xiao, Liang; Lou, Jin; Huang, Ruihong; Zhang, Qiongli; Du, Xin; Li, Ming; Wang, Daping; Shi, Dunyun

    2014-01-01

    The French-American-British (FAB) and WHO classifications provide important guidelines for the diagnosis, treatment, and prognostic prediction of acute leukemia, but are incapable of accurately differentiating all subtypes, and not well correlated with the clinical outcomes. In this study, we performed the protein profiling of the bone marrow mononuclear cells from the patients with acute leukemia and the health volunteers (control) by surface enhanced laser desorption/ionization-time of flight mass spectrometry (SELDI_TOF_MS). The patients with acute leukemia were analyzed as unitary by the profiling that were grouped into acute promyelocytic leukemia (APL), acute myeloid leukemia-granulocytic (AML-Gran), acute myeloid leukemia-monocytic (AML-Mon) acute lymphocytic leukemia (ALL), and control. Based on 109 proteomic signatures, the classification models of acute leukemia were constructed to screen the predictors by the improvement of the proteomic signatures and to detect their expression characteristics. According to the improvement and the expression characteristics of the predictors, the proteomic signatures (M3829, M1593, M2121, M2536, M1016) characterized successively each group (CON, APL, AML-Gra, AML-Mon, ALL) were screened as target molecules for identification. Meanwhile, the proteomic-based class of determinant samples could be made by the classification models. The credibility of the proteomic-based classification passed the evaluation of Biomarker Patterns Software 5.0 (BPS 5.0) scoring and validated application in clinical practice. The results suggested that the proteomic signatures characterized by different blasts were potential for developing new treatment and monitoring approaches of leukemia blasts. Moreover, the classification model was potential in serving as new diagnose approach of leukemia.

  4. Role of charge screening and delocalization for lipophilic cation permeability of model and mitochondrial membranes.

    Science.gov (United States)

    Trendeleva, Tatiana A; Sukhanova, Evgenia I; Rogov, Anton G; Zvyagilskaya, Renata A; Seveina, Inna I; Ilyasova, Tatiana M; Cherepanov, Dmitry A; Skulachev, Vladimir P

    2013-09-01

    The effects of the mitochondria-targeted lipophilic cation dodecyltriphenylphosphonium (C12TPP, the charge is delocalized and screened by bulky hydrophobic residues) and those of lipophilic cations decyltriethylammonium bromide and cetyltrimethylammonium bromide (C10TEA and C16TMA, the charges are localized and screened by less bulky residues) on bilayer planar phospholipid membranes and tightly-coupled mitochondria from the yeast Yarrowia lipolytica have been compared. In planar membranes, C12TPP was found to generate a diffusion potential as if it easily penetrates these membranes. In the presence of palmitate, C12TPP induced H(+) permeability like plastoquinonyl decyltriphenilphosphonium that facilitates transfer of fatty acid anions (Severin et al., PNAS, 2010, 107, 663-668). C12TPP was shown to stimulate State 4 respiration of mitochondria and caused a mitochondrial membrane depolarization with a half-maximal effect at 6μM. Besides, C12TPP profoundly potentiated the uncoupling effect of endogenous or added fatty acids. C10TEA and C16TMA inhibited State 4 respiration and decreased the membrane potential, though at much higher concentrations than C12TPP, and they did not promote the uncoupling action of fatty acids. These relationships were modeled by molecular dynamics. They can be explained by different membrane permeabilities for studied cations, which in turn are due to different availabilities of the positive charge in these cations to water dipoles. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Revisiting EOR Projects in Indonesia through Integrated Study: EOR Screening, Predictive Model, and Optimisation

    KAUST Repository

    Hartono, A. D.

    2017-10-17

    EOR preliminary analysis is pivotal to be performed at early stage of assessment in order to elucidate EOR feasibility. This study proposes an in-depth analysis toolkit for EOR preliminary evaluation. The toolkit incorporates EOR screening, predictive, economic, risk analysis and optimisation modules. The screening module introduces algorithms which assimilates statistical and engineering notions into consideration. The United States Department of Energy (U.S. DOE) predictive models were implemented in the predictive module. The economic module is available to assess project attractiveness, while Monte Carlo Simulation is applied to quantify risk and uncertainty of the evaluated project. Optimization scenario of EOR practice can be evaluated using the optimisation module, in which stochastic methods of Genetic Algorithms (GA), Particle Swarm Optimization (PSO) and Evolutionary Strategy (ES) were applied in the algorithms. The modules were combined into an integrated package of EOR preliminary assessment. Finally, we utilised the toolkit to evaluate several Indonesian oil fields for EOR evaluation (past projects) and feasibility (future projects). The attempt was able to update the previous consideration regarding EOR attractiveness and open new opportunity for EOR implementation in Indonesia.

  6. The geography of innovation: A new model of technology and innovation policies in a decentralised country

    OpenAIRE

    José Ignacio Pradas Poveda

    2002-01-01

    A new model of technology and innovation policies in a decentralised country is offered on the basis of the geography of innovation. This consists of an analysis combining the study of the nature of innovation and its close interrelationship with the space where innovation activities take place. The structure of the proposal incorporates the cyclical model of innovation and defines a role for every agent of the national innovation system (NIS) depending on specialisation, contribution and pot...

  7. Policy Model for the Livestock and Poultry Sectors of Mexico, A

    OpenAIRE

    Chad Barrett; Jacinto F. Fabiosa

    1998-01-01

    Many economic and demographic trends along with increased free trade agreements are projected to increase Mexico's prominence in the world markets for meat products in the next decade. This report documents the development by the Food and Agricultural Policy Research Institute (FAPRI) of a new model of Mexico's livestock and poultry sectors, including beef and cattle, swine and pork, and broilers. Improvements in the new model include functional form equations, more equations for each commodi...

  8. Screening California Current fishery management scenarios using the Atlantis end-to-end ecosystem model

    Science.gov (United States)

    Kaplan, Isaac C.; Horne, Peter J.; Levin, Phillip S.

    2012-09-01

    End-to-end marine ecosystem models link climate and oceanography to the food web and human activities. These models can be used as forecasting tools, to strategically evaluate management options and to support ecosystem-based management. Here we report the results of such forecasts in the California Current, using an Atlantis end-to-end model. We worked collaboratively with fishery managers at NOAA’s regional offices and staff at the National Marine Sanctuaries (NMS) to explore the impact of fishery policies on management objectives at different spatial scales, from single Marine Sanctuaries to the entire Northern California Current. In addition to examining Status Quo management, we explored the consequences of several gear switching and spatial management scenarios. Of the scenarios that involved large scale management changes, no single scenario maximized all performance metrics. Any policy choice would involve trade-offs between stakeholder groups and policy goals. For example, a coast-wide 25% gear shift from trawl to pot or longline appeared to be one possible compromise between an increase in spatial management (which sacrificed revenue) and scenarios such as the one consolidating bottom impacts to deeper areas (which did not perform substantially differently from Status Quo). Judged on a coast-wide scale, most of the scenarios that involved minor or local management changes (e.g. within Monterey Bay NMS only) yielded results similar to Status Quo. When impacts did occur in these cases, they often involved local interactions that were difficult to predict a priori based solely on fishing patterns. However, judged on the local scale, deviation from Status Quo did emerge, particularly for metrics related to stationary species or variables (i.e. habitat and local metrics of landed value or bycatch). We also found that isolated management actions within Monterey Bay NMS would cause local fishers to pay a cost for conservation, in terms of reductions in landed

  9. Public policy for children in Brazil – the process of implementation of a new model

    Directory of Open Access Journals (Sweden)

    Rodrigo Stumpf González

    2015-06-01

    Full Text Available Recently happened the 25th anniversary of the approval of the Child and Adolescent Statute. Which goals are achieved? What changed? This work analyses the Brazilian case in implementation of a new paradigm of children rights and his impact in the definition of aconcrete agenda of public policies, doing an evaluation of the new model and the changes, with focus of the development of a agenda of policies in four subjects: creation of councils, attention for the young lawbreakers, exploitation of child labour and sexual violence against children. At the end are discussed motivation for partial success in implementation of the agenda and responsibilities of the institutional actors involved.

  10. Democratic Model of Public Policy Accountability. Case Study on Implementation of Street Vendors Empowerment Policy in Makassar City

    Directory of Open Access Journals (Sweden)

    Rulinawaty Kasmadsi

    2015-08-01

    Full Text Available Policy accountability is a form of manifestation of public officials responsible to the people. One form of policy accountability that is discussed here is street vendors policy accountability, because they are a group of citizens who have the economic activities in public spaces. The existence of this policy how-ever, the number of street vendors from year to year increase in Makassar City. Therefore, this study seeks to uncover and explain the democratic policy ac-countability through the street vendors’ responses and expectations to the implementation of street ven-dors empowerment policy in Makassar City; and to uncover and explain the democratic policy account-ability through the stakeholders’ responses and ex-pectations to the implementation of street vendors empowerment policy in Makassar City. To achieve these objectives, the study uses democracy theory, in which this theory focuses on togetherness in dis-cussing solutions to the various problems of street vendors and in the policy implementation as well.This study used a qualitative design and case studies strat-egy. Data collection techniques used was observa-tion, interview, and documentation. Data were ana-lyzed with case description its settings. The results of this study pointed out that the interests and needs of the street vendors are not met through the empow-erment policies vendors. This is caused by the ab-sence of accountability forum as a place of togeth-erness all of street vendors empowerment stakehold-ers’. Street vendors empowerment policy in Makassar City are designed base on a top-down approach, so they are considered as objects, which must accept all government programs aimed at them.

  11. Predictive Models and Tools for Screening Chemicals under TSCA: Consumer Exposure Models 1.5

    Science.gov (United States)

    CEM contains a combination of models and default parameters which are used to estimate inhalation, dermal, and oral exposures to consumer products and articles for a wide variety of product and article use categories.

  12. Geographic Modeling to Quantify the Impact of Primary and Comprehensive Stroke Center Destination Policies.

    Science.gov (United States)

    Mullen, Michael T; Pajerowski, William; Messé, Steven R; Mechem, C Crawford; Jia, Judy; Abboud, Michael; David, Guy; Carr, Brendan G; Band, Roger

    2018-02-28

    We evaluated the impact of a primary stroke center (PSC) destination policy in a major metropolitan city and used geographic modeling to evaluate expected changes for a comprehensive stroke center policy. We identified suspected stroke emergency medical services encounters from 1/1/2004 to 12/31/2013 in Philadelphia, PA. Transport times were compared before and after initiation of a PSC destination policy on 10/3/2011. Geographic modeling estimated the impact of bypassing the closest hospital for the closest PSC and for the closest comprehensive stroke center. There were 2 326 943 emergency medical services runs during the study period, of which 15 099 had a provider diagnosis of stroke. Bypassing the closest hospital for a PSC was common before the official policy and increased steadily over time. Geographic modeling suggested that bypassing the closest hospital in favor of the closest PSC adds a median of 3.1 minutes to transport time. Bypassing to the closest comprehensive stroke center would add a median of 8.3 minutes. Within a large metropolitan area, the time cost of routing patients preferentially to PSCs and comprehensive stroke centers is low. © 2018 American Heart Association, Inc.

  13. Leaning against the Wind Policies on Vietnam’s Economy with DSGE Model

    Directory of Open Access Journals (Sweden)

    Phuc Huynh

    2017-01-01

    Full Text Available The global financial crisis of 2007–2008 had a negative impact on many countries, including Vietnam. Many policies have been applied to stabilize the macro-economic indicators. However, most of them are based on old qualitative models, which do not help policy makers understand deeply how each one affects the economy. In this paper, we investigate a quantitative macro-economic approach and use leaning against the wind policies with the Dynamic Stochastic General Equilibrium model (DSGE to find a better way to understand how policies stabilize the Vietnamese economy. Based on the framework of Gerali et al., we calibrate the hyper-parameter for Vietnam financial data and do the comparison between the standard Taylor rule and the cases in which we add asset price and credit elements. The results show that the credit-augmented Taylor rule is better than the asset-price-augmented one under the technology shock and contrary to the cost-push shock. Moreover, the extended simulation result shows that combining both asset-price and credit rules on the model is not useful for Vietnam’s economy in both types of shock.

  14. Does brain slices from pentylenetetrazole-kindled mice provide a more predictive screening model for antiepileptic drugs?

    DEFF Research Database (Denmark)

    Hansen, Suzanne L.; Sterjev, Zoran; Werngreen, Marie

    2012-01-01

    screening model for AEDs. To this end, we compared the in vitro and in vivo pharmacological profile of several selected AEDs (phenobarbital, phenytoin, tiagabine, fosphenytoin, valproate, and carbamazepine) along with citalopram using the PTZ-kindled model and brain slices from naïve, saline...

  15. Evolution of International Research Cooperation models in the Contemporary Foreign Policy Environment

    Directory of Open Access Journals (Sweden)

    Zhukovsky I.

    2015-08-01

    Full Text Available This article focuses on the principle models of international research and academic cooperation. The author divides international academic cooperation into periods and analyses the evolution of the connection between foreign policy and international cooperation in education and research aimed at raising the prestige and improving the position of a state in the international arena. The author focuses on the non-linear nature of periods stemming from the fact that different states are characterized by different (non-linear time cycles resulting from the differences in cultural and historical backgrounds and dissimilar foreign policy contents and formats. Through comparing a variety of foreign policy approaches (including that of the Russian Federation, the author answers the question about the contribution of universities to the development of mechanisms of cooperation and mutual understanding in the modern world — a world increasingly influenced by information and communication technologies.

  16. Social policies and activation in the Scandinavian welfare model: the case of Denmark

    DEFF Research Database (Denmark)

    Andersen, Torben M.

    Scandinavian countries are characterized by a generous tax-financed social safety net which provides insurance and performs a redistributive role. While contributing to lower inequality it may imply that incentives to work are low, and yet employment rates are high. How have the Scandinavian...... countries been able to reconcile social objectives with a high employment level? It is argued that the Scandinavian welfare model has a strong employment focus both because it is an important element in social policy based on social inclusion, but also because a collective welfare arrangement is only...... financially viable if (private) employment is sufficiently high. To ensure this, the social safety net includes a number of employment conditionalities (active labour market policies/workfare) to balance income protection with an employment focus. These policies are discussed using Denmark as an example...

  17. Health Policy in Physician Assistant Education: Teaching Considerations and a Model Curriculum.

    Science.gov (United States)

    Kidd, Vasco Deon; Cawley, James F; Kayingo, Gerald

    2016-03-01

    Recognition is growing within the medical academic community that future clinicians will need the tools to understand and influence health policy decisions. With the passage of the Patient Protection and Affordable Care Act of 2010, future clinicians will need not only clinical competence for successful practice but also an understanding of how health systems function. Although the fourth edition of the Accreditation Standards for Physician Assistant Education contains provisions and stipulations for the teaching of health topics in general and health policy specifically, physician assistant (PA) educators retain little consensus regarding either learning objectives or specific rubrics for teaching these important concepts. In this article, we discuss approaches for teaching health policy, delineate useful educational resources for PA faculty, and propose a model curriculum.

  18. Local health departments implement a theory-based model to increase breast and cervical cancer screening.

    Science.gov (United States)

    Suarez, L; Nichols, D C; Pulley, L; Brady, C A; McAlister, A

    1993-01-01

    Su Vida, Su Salud/Your Life, Your Health is a community program to increase participation in breast and cervical cancer screening. This program illustrates the diffusion of an innovative outreach strategy from a research environment to two local health departments. The program uses A Su Salud, the communication model in which positive role models are featured in the media, and community volunteers who give positive social reinforcement. Local health departments in Galveston and Corpus Christi, TX, were selected to implement the model because of excessive mortality rates in the region and the departments' adequate level of resources and commitment. Over an 18-month period, 54 stories of role models appeared in the media in Corpus Christi, and 60 appeared in Galveston. There were 490 volunteers active in Corpus Christi and 279 in Galveston. Of 365 inquiries to the Corpus Christi program, 35 percent were from the Mexican American target group of women ages 40-70. Of 1,457 women who contacted the Galveston program, 9 percent were from the African American target group ages 40-70. Local health departments are well-suited to participation in cancer control research applications because they have direct access to high-risk populations and have the authority to institutionalize effective interventions.

  19. Screening of persistent organic pollutants by QSPR classification models: a comparative study.

    Science.gov (United States)

    Papa, Ester; Gramatica, Paola

    2008-08-01

    A Quantitative Structure-Property Relationships (QSPRs) study for the prediction of the environmental persistence of a set of 250 heterogeneous organic compounds is here presented. Three a priori defined classes of environmental persistence were generated, by Hierarchical Cluster Analysis, from the combination of half-life data in air, water, soil and sediment available for all the studied compounds. QSPR classification models were successfully developed using different techniques (k-NN, CART and CP-ANN) and three interpretable theoretical molecular descriptors. Robust external validation was provided by statistical splitting and also on completely new data. The good performances of all these models were compared and their structural domains were analyzed. The analysis of the errors highlights a slight tendency of persistence overestimation, misclassifying chemicals from a lower to a higher class of persistence, in line with the precautionary principle. Finally, the reliability of the proposed QSPR models was verified further with new data from the literature. The structure-based classification models, applicable for the prediction of potential persistence of heterogeneous organic compounds, could be useful as preliminary support tools for the identification and prioritization of new potential POPs among already existing chemicals as well as "screening prior to synthesis" procedures to avoid the production, and consequent release into the environment, of new POPs.

  20. QSAR classification models for the screening of the endocrine-disrupting activity of perfluorinated compounds.

    Science.gov (United States)

    Kovarich, S; Papa, E; Li, J; Gramatica, P

    2012-01-01

    Perfluorinated compounds (PFCs) are a class of emerging pollutants still widely used in different materials as non-adhesives, waterproof fabrics, fire-fighting foams, etc. Their toxic effects include potential for endocrine-disrupting activity, but the amount of experimental data available for these pollutants is limited. The use of predictive strategies such as quantitative structure-activity relationships (QSARs) is recommended under the REACH regulation, to fill data gaps and to screen and prioritize chemicals for further experimentation, with a consequent reduction of costs and number of tested animals. In this study, local classification models for PFCs were developed to predict their T4-TTR (thyroxin-transthyretin) competing potency. The best models were selected by maximizing the sensitivity and external predictive ability. These models, characterized by robustness, good predictive power and a defined applicability domain, were applied to predict the activity of 33 other PFCs of environmental concern. Finally, classification models recently published by our research group for T4-TTR binding of brominated flame retardants and for estrogenic and anti-androgenic activity were applied to the studied perfluorinated chemicals to compare results and to further evaluate the potential for these PFCs to cause endocrine disruption.

  1. High-throughput screen for novel antimicrobials using a whole animal infection model.

    Science.gov (United States)

    Moy, Terence I; Conery, Annie L; Larkins-Ford, Jonah; Wu, Gang; Mazitschek, Ralph; Casadei, Gabriele; Lewis, Kim; Carpenter, Anne E; Ausubel, Frederick M

    2009-07-17

    The nematode Caenorhabditis elegans is a unique whole animal model system for identifying small molecules with in vivo anti-infective properties. C. elegans can be infected with a broad range of human pathogens, including Enterococcus faecalis, an important human nosocomial pathogen. Here, we describe an automated, high-throughput screen of 37,200 compounds and natural product extracts for those that enhance survival of C. elegans infected with E. faecalis. Using a robot to dispense live, infected animals into 384-well plates and automated microscopy and image analysis, we identified 28 compounds and extracts not previously reported to have antimicrobial properties, including six structural classes that cure infected C. elegans animals but do not affect the growth of the pathogen in vitro, thus acting by a mechanism of action distinct from antibiotics currently in clinical use.

  2. Robust ridge regression estimators for nonlinear models with applications to high throughput screening assay data.

    Science.gov (United States)

    Lim, Changwon

    2015-03-30

    Nonlinear regression is often used to evaluate the toxicity of a chemical or a drug by fitting data from a dose-response study. Toxicologists and pharmacologists may draw a conclusion about whether a chemical is toxic by testing the significance of the estimated parameters. However, sometimes the null hypothesis cannot be rejected even though the fit is quite good. One possible reason for such cases is that the estimated standard errors of the parameter estimates are extremely large. In this paper, we propose robust ridge regression estimation procedures for nonlinear models to solve this problem. The asymptotic properties of the proposed estimators are investigated; in particular, their mean squared errors are derived. The performances of the proposed estimators are compared with several standard estimators using simulation studies. The proposed methodology is also illustrated using high throughput screening assay data obtained from the National Toxicology Program. Copyright © 2014 John Wiley & Sons, Ltd.

  3. Global perspectives on nursing and its contribution to healthcare and health policy: thoughts on an emerging policy model.

    Science.gov (United States)

    Shamian, Judith

    2014-12-01

    We know from rigorous evidence that nurses can exert an incredible impact on the everyday lives of people and their health. Nurses can also contribute in much wider spheres of influence by applying their knowledge and skills to address broader issues affecting population health across communities, nations and globally. Despite the prevalence of so many vexing health and social issues, nurses often fail to think globally, or even regionally, when they are lobbying for change. And while much political influence is local, some issues are simply too complex to rely on local influence alone. Importantly in all this, we must acknowledge the ways these complex health issues are shaped by economic and political agendas and not necessarily by healthcare agendas. As such, the nursing community has to act globally and locally, both within and outside of the nursing arena. This paper explores early thinking about an evolving model of spheres--or "bubbles"--of policy influence in which nurses can and must operate to more effectively impact key global health and healthcare challenges.

  4. Target discovery screens using pooled shRNA libraries and next-generation sequencing: A model workflow and analytical algorithm.

    Directory of Open Access Journals (Sweden)

    Christiane Schaefer

    Full Text Available In the search for novel therapeutic targets, RNA interference screening has become a valuable tool. High-throughput technologies are now broadly accessible but their assay development from baseline remains resource-intensive and challenging. Focusing on this assay development process, we here describe a target discovery screen using pooled shRNA libraries and next-generation sequencing (NGS deconvolution in a cell line model of Ewing sarcoma. In a strategy designed for comparative and synthetic lethal studies, we screened for targets specific to the A673 Ewing sarcoma cell line. Methods, results and pitfalls are described for the entire multi-step screening procedure, from lentiviral shRNA delivery to bioinformatics analysis, illustrating a complete model workflow. We demonstrate that successful studies are feasible from the first assay performance and independent of specialized screening units. Furthermore, we show that a resource-saving screen depth of 100-fold average shRNA representation can suffice to generate reproducible target hits despite heterogeneity in the derived datasets. Because statistical analysis methods are debatable for such datasets, we created ProFED, an analysis package designed to facilitate descriptive data analysis and hit calling using an aim-oriented profile filtering approach. In its versatile design, this open-source online tool provides fast and easy analysis of shRNA and other count-based datasets to complement other analytical algorithms.

  5. Indigeneity-Grounded Analysis (IGA as Policy(-Making Lens: New Zealand Models, Canadian Realities

    Directory of Open Access Journals (Sweden)

    Roger Maaka

    2010-05-01

    Full Text Available Engaging politically with the principles of indigeneity is neither an option nor a cop out. The emergence of Indigenous peoples as prime-time players on the world’s political stage attests to the timeliness and relevance of indigeneity in advancing a new postcolonial contract for living together differently. Insofar as the principles of indigeneity are inextricably linked with challenge, resistance, and transformation, this paper argues that reference to indigeneity as policy(- making paradigm is both necessary and overdue. To put this argument to the test, the politics of Maori indigeneity in Aotearoa New Zealand are analyzed and assessed in constructing an indigeneity agenda model. The political implications of an indigeneity-policy nexus are then applied to the realities of Canada’s Indigenous/Aboriginal peoples. The paper contends that, just as the Government is committed to a gender based analysis (GBA for improving policy outcomes along gender lines, so too should the principles of indigeneity (or aboriginality secure an indigeneity grounded analysis (IGA framework for minimizing systemic policy bias while maximizing Indigenous peoples inputs. The paper concludes by theorizing those provisional first principles that inform an IGA framework as a policy (-making lens.

  6. Upending the social ecological model to guide health promotion efforts toward policy and environmental change.

    Science.gov (United States)

    Golden, Shelley D; McLeroy, Kenneth R; Green, Lawrence W; Earp, Jo Anne L; Lieberman, Lisa D

    2015-04-01

    Efforts to change policies and the environments in which people live, work, and play have gained increasing attention over the past several decades. Yet health promotion frameworks that illustrate the complex processes that produce health-enhancing structural changes are limited. Building on the experiences of health educators, community activists, and community-based researchers described in this supplement and elsewhere, as well as several political, social, and behavioral science theories, we propose a new framework to organize our thinking about producing policy, environmental, and other structural changes. We build on the social ecological model, a framework widely employed in public health research and practice, by turning it inside out, placing health-related and other social policies and environments at the center, and conceptualizing the ways in which individuals, their social networks, and organized groups produce a community context that fosters healthy policy and environmental development. We conclude by describing how health promotion practitioners and researchers can foster structural change by (1) conveying the health and social relevance of policy and environmental change initiatives, (2) building partnerships to support them, and (3) promoting more equitable distributions of the resources necessary for people to meet their daily needs, control their lives, and freely participate in the public sphere. © 2015 Society for Public Health Education.

  7. An inventory model with a new credit drift: Flexible trade credit policy

    Directory of Open Access Journals (Sweden)

    Ankit Prakash Tyagi

    2016-01-01

    Full Text Available In most of the published articles dealing with optimal order quantity model under permissible delay in payments, it is assumed that the supplier only put forwards fully permissible delay in payments if retailer ordered a bulky sufficient quantity otherwise permissible delay in payments would not be permitted. Practically, in competitive market environments and recession phases of business, every supplier wants to attract more retailers by the help of providing good facilities for trading. Necessity of order quantity may put a negative pressure on supplier’s demand. So, within the economic order quantity (EOQ framework the main purpose of this paper is to broaden this extreme case by introducing a new credit policy, Flexible Trade Credit Policy (FTCP, for supplier which can help him provide more free space of trading to retailers. This policy, after adopting by suppliers, not only provides attractive trading environments for retailers but also enhances the demand of supplier due to the large number of new retailers. Here in, under this policy, an inventory system is investigated as a cost minimization problem to establish the retailer’s optimal inventory cycle time and optimal order quantity. Three theorems are established to describe and to lighten optimal replenishment policies for the retailer. Finally, numerical examples are considered to illustrate all these theorems and managerial insights are given based on considered numerical examples.

  8. Monetary Policy and Industrial Output in the BRICS Countries: A Markov-Switching Model

    Directory of Open Access Journals (Sweden)

    Kutu Adebayo Augustine

    2017-12-01

    Full Text Available This paper examines whether the five BRICS countries share similar business cycles and determines the probability of any of the countries moving from a contractionary regime to an expansionary regime. The study further examines the extent to which changes in monetary policy affect industrial output in expansions relative to contractions. Employing the Peersman and Smets (2001 Markov-Switching Model (MSM and monthly data from 1994.01–2013.12, the study reveals that the five BRICS countries have similar business cycles. The results further demonstrate that the BRICS countries’ business cycles are characterized by two distinct growth rate phases: a contractionary regime and an expansionary regime. It can also be observed that the area-wide monetary policy has significantly large effects on industrial output in recessions as well as in booms. It has also been established that there is a high probability of moving from state one (recession to state two (expansion and that on average, the probabilities of staying in state 2 (expansion are high for each of the five countries. It is, therefore, recommended that the BRICS countries should sustain uniform policy consistency (monetary policy, especially as they formulate and implement economic policies to stimulate industrial output.

  9. Policy Debate | Learning to Grow Beyond the Middle-Income Trap - Singapore as an Export Model?

    Directory of Open Access Journals (Sweden)

    Raymond Saner

    2014-12-01

    Full Text Available Editor’s note: These papers are a contribution to the ‘Policy Debate’ section of International Development Policy. In this section, academics, policy-makers and practioners engage in a dialogue on global development challenges. Papers are copy-edited but not peer-reviewed. Instead, the initial thematic contribution is followed by critical comments and reactions from scholars and/or policy-makers. This debate can be pursued on the Journal’s blog http://devpol.hypotheses.org/528 where you are invited to share your reflections under your name.In the initial paper ‘Learning to Grow’, the authors argue that a key challenge for middle-income countries is to avoid ‘the middle-income trap’. In this situation, economic growth has come to a halt and a country is unable to transition to the next level in part due to inadequacies in high-level human capital. Taking the example of Singapore as a country that has avoided the middle-income trap, the authors call for ‘a much closer alignment of policies for human capital and economic development’ and a ‘human capital focussed development strategy’. In his answer, Professor Gopinathan, from the National University of Singapore, analyses some key conditions that were crucial for Singapore’s success and questions whether the model could be exported to other contexts.

  10. Neuronal models for evaluation of proliferation in vitro using high content screening

    International Nuclear Information System (INIS)

    Mundy, William R.; Radio, Nicholas M.; Freudenrich, Theresa M.

    2010-01-01

    In vitro test methods can provide a rapid approach for the screening of large numbers of chemicals for their potential to produce toxicity (hazard identification). In order to identify potential developmental neurotoxicants, a battery of in vitro tests for neurodevelopmental processes such as cell proliferation, differentiation, growth, and synaptogenesis has been proposed. The development of in vitro approaches for toxicity testing will require choosing a model system that is appropriate to the endpoint of concern. This study compared several cell lines as models for neuronal proliferation. The sensitivities of neuronal cell lines derived from three species (PC12, rat; N1E-115, mouse; SH-SY5Y, human) to chemicals known to affect cell proliferation were assessed using a high content screening system. After optimizing conditions for cell growth in 96-well plates, proliferation was measured as the incorporation of 5-bromo-2'-deoxyuridine (BrdU) into replicating DNA during S phase. BrdU-labeled cells were detected by immunocytochemistry and cell counts were obtained using automated image acquisition and analysis. The three cell lines showed approximately 30-40% of the population in S phase after a 4 h pulse of BrdU. Exposure to the DNA polymerase inhibitor aphidicolin for 20 h prior to the 4 h pulse of BrdU significantly decreased proliferation in all three cell lines. The sensitivities of the cell lines were compared by exposure to eight chemicals known to affect proliferation (positive controls) and determination of the concentration inhibiting proliferation by 50% of control (I 50 ). PC12 cells were the most sensitive to chemicals; 6 out of 8 chemicals (aphidicolin, cadmium, cytosine arabinoside, dexamethasone, 5-fluorouracil, and methylmercury) inhibited proliferation at the concentrations tested. SH-SY5Y cells were somewhat less sensitive to chemical effects, with five out of eight chemicals inhibiting proliferation; dexamethasone had no effect, and cadmium

  11. Prospective identification of adolescent suicide ideation using classification tree analysis: Models for community-based screening.

    Science.gov (United States)

    Hill, Ryan M; Oosterhoff, Benjamin; Kaplow, Julie B

    2017-07-01

    Although a large number of risk markers for suicide ideation have been identified, little guidance has been provided to prospectively identify adolescents at risk for suicide ideation within community settings. The current study addressed this gap in the literature by utilizing classification tree analysis (CTA) to provide a decision-making model for screening adolescents at risk for suicide ideation. Participants were N = 4,799 youth (Mage = 16.15 years, SD = 1.63) who completed both Waves 1 and 2 of the National Longitudinal Study of Adolescent to Adult Health. CTA was used to generate a series of decision rules for identifying adolescents at risk for reporting suicide ideation at Wave 2. Findings revealed 3 distinct solutions with varying sensitivity and specificity for identifying adolescents who reported suicide ideation. Sensitivity of the classification trees ranged from 44.6% to 77.6%. The tree with greatest specificity and lowest sensitivity was based on a history of suicide ideation. The tree with moderate sensitivity and high specificity was based on depressive symptoms, suicide attempts or suicide among family and friends, and social support. The most sensitive but least specific tree utilized these factors and gender, ethnicity, hours of sleep, school-related factors, and future orientation. These classification trees offer community organizations options for instituting large-scale screenings for suicide ideation risk depending on the available resources and modality of services to be provided. This study provides a theoretically and empirically driven model for prospectively identifying adolescents at risk for suicide ideation and has implications for preventive interventions among at-risk youth. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  12. Phenotypic Screening Identifies Modulators of Amyloid Precursor Protein Processing in Human Stem Cell Models of Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Philip W. Brownjohn

    2017-04-01

    Full Text Available Summary: Human stem cell models have the potential to provide platforms for phenotypic screens to identify candidate treatments and cellular pathways involved in the pathogenesis of neurodegenerative disorders. Amyloid precursor protein (APP processing and the accumulation of APP-derived amyloid β (Aβ peptides are key processes in Alzheimer's disease (AD. We designed a phenotypic small-molecule screen to identify modulators of APP processing in trisomy 21/Down syndrome neurons, a complex genetic model of AD. We identified the avermectins, commonly used as anthelmintics, as compounds that increase the relative production of short Aβ peptides at the expense of longer, potentially more toxic peptides. Further studies demonstrated that this effect is not due to an interaction with the core γ-secretase responsible for Aβ production. This study demonstrates the feasibility of phenotypic drug screening in human stem cell models of Alzheimer-type dementia, and points to possibilities for indirectly modulating APP processing, independently of γ-secretase modulation. : In this article, Livesey and colleagues perform a phenotypic drug screen in a human stem cell model of Alzheimer's disease. The anthelminthic avermectins are identified as a family of compounds that increase the production of short Aβ peptides over longer more toxic Aβ forms. The effect is analogous to existing γ-secretase modulators, but is independent of the core γ-secretase complex. Keywords: neural stem cells, Alzheimer's disease, phenotypic screening, iPSCs, human neurons, dementia, Down syndrome, amyloid beta, ivermectin, selamectin

  13. A modelling study to evaluate the costs and effects of lowering the starting age of population breast cancer screening.

    Science.gov (United States)

    Koleva-Kolarova, Rositsa G; Daszczuck, Alicja M; de Jonge, Chris; Abu Hantash, Mohd Kahlil; Zhan, Zhuozhao Z; Postema, Erik Jan; Feenstra, Talitha L; Pijnappel, Ruud M; Greuter, Marcel J W; de Bock, Geertruida H

    2018-03-01

    Because the incidence of brea