WorldWideScience

Sample records for models demographic consequences

  1. Demographic Consequences of Defeating Aging

    OpenAIRE

    Gavrilov, Leonid A.; Gavrilova, Natalia S.

    2010-01-01

    A common objection against starting a large-scale biomedical war on aging is the fear of catastrophic population consequences (overpopulation). This fear is only exacerbated by the fact that no detailed demographic projections for radical life extension scenario have been conducted so far. This study explores different demographic scenarios and population projections, in order to clarify what could be the demographic consequences of a successful biomedical war on aging. A general conclusion o...

  2. CONSEQUENCES OF THE DEMOGRAPHIC CRISIS

    Directory of Open Access Journals (Sweden)

    LIVIU RADU

    2014-11-01

    Full Text Available Major dysfunctionalities can arise from the demographic decline, both on a social level and from the perspective of the economic-financial evolution of the world’s states. The obvious aging of the industrialized states’ population overlapping the import of cheap workforce in the developing countries can start mutations whose consequences are somewhat predictable but discouraging. An accelerated urbanization of the states is foreseen, as well as the decrease of birthrates, negative external migration, increase of mortality and its stagnation in a larger value than that of the birthrate, and not least the population’s aging will hinder a part of the developing countries to sustain a high rhythm of long-term economical increase. The socialeconomic consequences will be reflected in the labor market, the householders’ amount of income as well as in the education’s level. All of these aspects call for a rethinking of the public politics, especially of the social insurance’s system and of the education, a reorientation of the economy based on the increase of specializing in production and productivity, as well as a financial stability unburdened by the politics’ interference in the business environment.

  3. Ecological and demographic consequences of a nuclear war

    International Nuclear Information System (INIS)

    Svirezhev, Y.M.

    1987-01-01

    The impact of a nuclear war upon ecological and demographic processes is estimated. The direct effect of nuclear detonations, the radioactive contamination of territories, the pollution by heavy metals and acid rain, as well as the effect of the sharp decline in temperature of the atmosphere ('nuclear winter') are taken into consideration. Estimated is the extent of destruction for the ecosystems of different types. The recovery of ecosystems is shown to be extremely slow or impossible. Demographic and genetic predictions for the nuclear war consequences are presented for various regions of the world. (author)

  4. [The demographic consequences of austerity in Latin America: methodological aspects].

    Science.gov (United States)

    Hakkert, R

    1991-01-01

    This work reviews evidence in the literature of possible demographic effects of the austerity programs imposed on Latin American countries in the 1980s. The work focuses on methodological problems involved in assessing demographic changes and ascertaining that they were indeed attributable to the economic crisis. An introductory section describes the recession of the 1980s in Latin America, the declines in employment and living standards, and the health and social consequences of the deepening poverty. But the author argues that evaluation of health conditions, levels of nutrition, and especially factors such as infant mortality, fertility, marriage patterns, and migration as indicators of the impact of the economic depression is full of pitfalls that are not always obvious. Few Latin American countries have civil registration systems capable of providing accurate and up-to-date mortality and fertility data. Indirect methods currently in use were intended to analyze longterm levels and trends and are of little use for short-term fluctuations. Data on internal migration are scarce even in developed countries. Even when recent data are available it is often difficult or impossible to obtain data for comparison. Infant mortality and malnutrition levels, for example, are serious problems in many parts of Latin America, but series of data capable of demonstrating that they are truly consequences of the economic crisis are lacking. Another challenge is to separate the demographic effects of the debt crisis from longterm structural processes. The possibility of time lags and of different time frames may increase confusion. Almost a year must pass before effects on birth rates can be expected, for example. Neutralizing mechanisms may obscure the effects sought. Thus, the most impoverished urban sectors may return to the countryside to seek refuge in subsistence agriculture; their departure would in some measure diminish the consequences of recession in the urban economy

  5. Demographic Modelling in Weed Biocontrol

    Science.gov (United States)

    Demographic matrix modeling of plant populations can be a powerful tool to identify key life stage transitions that contribute the most to population growth of an invasive plant and hence should be targeted for disruption. Therefore, this approach has the potential to guide the pre-release selection...

  6. Responsive survey design, demographic data collection, and models of demographic behavior.

    Science.gov (United States)

    Axinn, William G; Link, Cynthia F; Groves, Robert M

    2011-08-01

    To address declining response rates and rising data-collection costs, survey methodologists have devised new techniques for using process data ("paradata") to address nonresponse by altering the survey design dynamically during data collection. We investigate the substantive consequences of responsive survey design-tools that use paradata to improve the representative qualities of surveys and control costs. By improving representation of reluctant respondents, responsive design can change our understanding of the topic being studied. Using the National Survey of Family Growth Cycle 6, we illustrate how responsive survey design can shape both demographic estimates and models of demographic behaviors based on survey data. By juxtaposing measures from regular and responsive data collection phases, we document how special efforts to interview reluctant respondents may affect demographic estimates. Results demonstrate the potential of responsive survey design to change the quality of demographic research based on survey data.

  7. The demographic consequences of mutualism: ants increase host-plant fruit production but not population growth.

    Science.gov (United States)

    Ford, Kevin R; Ness, Joshua H; Bronstein, Judith L; Morris, William F

    2015-10-01

    The impact of mutualists on a partner's demography depends on how they affect the partner's multiple vital rates and how those vital rates, in turn, affect population growth. However, mutualism studies rarely measure effects on multiple vital rates or integrate them to assess the ultimate impact on population growth. We used vital rate data, population models and simulations of long-term population dynamics to quantify the demographic impact of a guild of ant species on the plant Ferocactus wislizeni. The ants feed at the plant's extrafloral nectaries and attack herbivores attempting to consume reproductive organs. Ant-guarded plants produced significantly more fruit, but ants had no significant effect on individual growth or survival. After integrating ant effects across these vital rates, we found that projected population growth was not significantly different between unguarded and ant-guarded plants because population growth was only weakly influenced by differences in fruit production (though strongly influenced by differences in individual growth and survival). However, simulations showed that ants could positively affect long-term plant population dynamics through services provided during rare but important events (herbivore outbreaks that reduce survival or years of high seedling recruitment associated with abundant precipitation). Thus, in this seemingly clear example of mutualism, the interaction may actually yield no clear benefit to plant population growth, or if it does, may only do so through the actions of the ants during rare events. These insights demonstrate the value of taking a demographic approach to studying the consequences of mutualism.

  8. Demographic Modeling Via 3-dimensional Markov Chains

    OpenAIRE

    Viquez, Juan Jose; Campos, Alexander; Loria, Jorge; Mendoza, Luis Alfredo; Viquez, Jorge Aurelio

    2017-01-01

    This article presents a new model for demographic simulation which can be used to forecast and estimate the number of people in pension funds (contributors and retirees) as well as workers in a public institution. Furthermore, the model introduces opportunities to quantify the financial ows coming from future populations such as salaries, contributions, salary supplements, employer contribution to savings/pensions, among others. The implementation of this probabilistic model will be of great ...

  9. Demographic consequences of nest box use for Red-footed Falcons Falco vespertinus in Central Asia

    Science.gov (United States)

    Bragin, Evgeny A.; Bragin, Alexander E.; Katzner, Todd

    2017-01-01

    Nest box programs are frequently implemented for the conservation of cavity-nesting birds, but their effectiveness is rarely evaluated in comparison to birds not using nest boxes. In the European Palearctic, Red-footed Falcon Falco vespertinus populations are both of high conservation concern and are strongly associated with nest box programs in heavily managed landscapes. We used a 21-year monitoring dataset collected on 753 nesting attempts by Red-footed Falcons in unmanaged natural or semi-natural habitats to provide basic information on this poorly known species; to evaluate long-term demographic trends; and to evaluate response of demographic parameters of Red-footed Falcons to environmental factors including use of nest boxes. We observed significant differences among years in laying date, offspring loss, and numbers of fledglings produced, but not in egg production. Of these four parameters, offspring loss and, to a lesser extent, number of fledglings exhibited directional trends over time. Variation in laying date and in numbers of eggs were not well explained by any one model, but instead by combinations of models, each with informative terms for nest type. Nevertheless, laying in nest boxes occurred 2.10 ± 0.70 days earlier than in natural nests. In contrast, variation in both offspring loss and numbers of fledglings produced were fairly well explained by a single model including terms for nest type, nest location, and an interaction between the two parameters (65% and 81% model weights respectively), with highest offspring loss in nest boxes on forest edges. Because, for other species, earlier laying dates are associated with more fit individuals, this interaction highlighted a possible ecological trap, whereby birds using nest boxes on forest edges lay eggs earlier but suffer greater offspring loss and produce lower numbers of fledglings than do those in other nesting settings. If nest boxes increase offspring loss for Red-footed Falcons in heavily

  10. Do Demographic Variables Moderate the Relationship Between Job Burnout and its Consequences?

    Directory of Open Access Journals (Sweden)

    Hasan Zarei Matin

    2012-01-01

    Full Text Available Many studies have already been conducted to understand the various dimensions of the burnout. The purpose of the present research is to investigate the moderating effect of demographic variables on the relationship between job burnout and its consequences among the staff of an Iranian public sector company. In this research, job burnout is considered as independent variable; organizational commitment, intention to leave and the employees‟ job satisfaction are dependent variables; and the age, gender, marital status and educational level are moderating variables. The results of this study show that firstly, the job burnout of employees in organizations leads to the decrease of organizational commitment and job satisfaction, and the increase of intention to leave; secondly, the demographic variables in this research don't affect on the relationship of job burnout with its consequences.

  11. Demographic consequences of poison-related mortality in a threatened bird of prey.

    Directory of Open Access Journals (Sweden)

    Simone Tenan

    Full Text Available Evidence for decline or threat of wild populations typically comes from multiple sources and methods that allow optimal integration of the available information, representing a major advance in planning management actions. We used integrated population modelling and perturbation analyses to assess the demographic consequences of the illegal use of poison for an insular population of Red Kites, Milvus milvus. We first pooled into a single statistical framework the annual census of breeding pairs, the available individual-based data, the average productivity and the number of birds admitted annually to the local rehabilitation centre. By combining these four types of information we were able to increase estimate precision and to obtain an estimate of the proportion of breeding adults, an important parameter that was not directly measured in the field and that is often difficult to assess. Subsequently, we used perturbation analyses to measure the expected change in the population growth rate due to a change in poison-related mortality. We found that poison accounted for 0.43 to 0.76 of the total mortality, for yearlings and older birds, respectively. Results from the deterministic population model indicated that this mortality suppressed the population growth rate by 20%. Despite this, the population was estimated to increase, albeit slowly. This positive trend was likely maintained by a very high productivity (1.83 fledglings per breeding pair possibly promoted by supplementary feeding, a situation which is likely to be common to many large obligate or facultative European scavengers. Under this hypothetical scenario of double societal costs (poisoning of a threatened species and feeding programs, increasing poison control would help to lower the public cost of maintaining supplementary feeding stations.

  12. Nutrition pathways in consequence modeling

    International Nuclear Information System (INIS)

    Tveten, U.

    1982-01-01

    During 1979-1980 calculations of risk from waste transportation by truck (fire following collision) and fire in temporary storage for waste were performed. A modified version of the consequence model of WASH-1400 (CRAC) was used. Two exposure pathways dominated the results: external exposure from material on the ground and exposure via nutrition. Many of the parameters entering into the nutrition calculations will depend upon local conditions, like soil composition, crop yield, etc. It was decided to collect detailed comments upon the CRAC nutritions model and parameter values from radioecologists in the four Nordic countries. Four alternate sets of parameter values were derived from these comments, and new risk calculations were performed

  13. Medico-demographic criteria in estimating the consequences of the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Linge, I I; Melikhova, I A; Pavlovski, O [Nuclear Safety Inst., Academy of Sciences, Moscow (Russian Federation)

    1997-09-01

    Correct comparison of population statistics in affected and unaffected areas prior to and after the accident allows to detect any noticeable deviations in basic medico-demographic parameters in contaminated territories from common trends. In view of that when in 1990 in Nuclear Safety Institute a start has been made on construction of an information support system for government and regional executives to overcome the consequences of the Chernobyl disaster a specialized data bank on demography and medical statistics (MDBD) was created. 12 refs, 7 figs, 8 tabs.

  14. Medico-demographic criteria in estimating the consequences of the Chernobyl accident

    International Nuclear Information System (INIS)

    Linge, I.I.; Melikhova, I.A.; Pavlovski, O.

    1997-01-01

    Correct comparison of population statistics in affected and unaffected areas prior to and after the accident allows to detect any noticeable deviations in basic medico-demographic parameters in contaminated territories from common trends. In view of that when in 1990 in Nuclear Safety Institute a start has been made on construction of an information support system for government and regional executives to overcome the consequences of the Chernobyl disaster a specialized data bank on demography and medical statistics (MDBD) was created. 12 refs, 7 figs, 8 tabs

  15. Genetic demographic networks: Mathematical model and applications.

    Science.gov (United States)

    Kimmel, Marek; Wojdyła, Tomasz

    2016-10-01

    Recent improvement in the quality of genetic data obtained from extinct human populations and their ancestors encourages searching for answers to basic questions regarding human population history. The most common and successful are model-based approaches, in which genetic data are compared to the data obtained from the assumed demography model. Using such approach, it is possible to either validate or adjust assumed demography. Model fit to data can be obtained based on reverse-time coalescent simulations or forward-time simulations. In this paper we introduce a computational method based on mathematical equation that allows obtaining joint distributions of pairs of individuals under a specified demography model, each of them characterized by a genetic variant at a chosen locus. The two individuals are randomly sampled from either the same or two different populations. The model assumes three types of demographic events (split, merge and migration). Populations evolve according to the time-continuous Moran model with drift and Markov-process mutation. This latter process is described by the Lyapunov-type equation introduced by O'Brien and generalized in our previous works. Application of this equation constitutes an original contribution. In the result section of the paper we present sample applications of our model to both simulated and literature-based demographies. Among other we include a study of the Slavs-Balts-Finns genetic relationship, in which we model split and migrations between the Balts and Slavs. We also include another example that involves the migration rates between farmers and hunters-gatherers, based on modern and ancient DNA samples. This latter process was previously studied using coalescent simulations. Our results are in general agreement with the previous method, which provides validation of our approach. Although our model is not an alternative to simulation methods in the practical sense, it provides an algorithm to compute pairwise

  16. Demographic consequences of invasion by a native, controphic competitor to an insular bird population.

    Science.gov (United States)

    Johnson, K M; Germain, R R; Tarwater, C E; Reid, J M; Arcese, P

    2018-05-01

    Species invasions and range shifts can lead to novel competitive interactions between historically resident and colonizing species, but the demographic consequences of such interactions remain controversial. We present results from field experiments and 45 years of demographic monitoring to test the hypothesis that the colonization of Mandarte Is., BC, Canada, by fox sparrows (Passerella iliaca) caused the long-term decline of the resident population of song sparrows (Melospiza melodia). Several lines of evidence indicate that competition with fox sparrows for winter food reduced over-winter survival in juvenile song sparrows by 48% from 1960 to 2015, enforcing population decline despite an increase in annual reproductive rate in song sparrows over the same period. Preference for locally abundant seeds presented at experimental arenas suggested complete overlap in diet in song and fox sparrows, and observations at arenas baited with commercial seed showed that fox sparrows displaced song sparrows in 91-100% of interactions in two periods during winter. In contrast, we found no evidence of interspecific competition for resources during the breeding season. Our results indicate that in the absence of marked shifts in niche dimension, range expansions by dominant competitors have the potential to cause the extirpation of historically resident species when competitive interactions between them are strong and resources not equitably partitioned.

  17. Demographic Consequences of Gender Discrimination in China: Simulation Analysis of Policy Options

    OpenAIRE

    Quanbao, Jiang; Shuzhuo, Li; Marcus W., Feldman

    2011-01-01

    The large number of missing females in China, a consequence of gender discrimination, is having and will continue to have a profound effect on the country's population development. In this paper, we analyze the causes of this gender discrimination in terms of institutions, culture and, economy, and suggest public policies that might help eliminate gender discrimination. Using a population simulation model, we study the effect of public policies on the sex ratio at birth and excess female chil...

  18. Education, labour, and the demographic consequences of birth postponement in Europe

    Directory of Open Access Journals (Sweden)

    Hippolyte d'Albis

    2017-02-01

    Full Text Available Background: This article questions the demographic consequences of birth postponement in Europe. Objective: Starting from the fact that there is no obvious link between the timing of first births and fertility levels in Europe, we find that under certain circumstances, birth postponement potentially facilitates rather than impedes starting a family. Methods: We apply a synthetic cohort approach and distinguish between different socioeconomic determinants of the timing of first births by using the European Union Statistics on Income and Living Conditions (EU-SILC. Data is compiled specifically to reduce endogeneity and to eliminate structure effects. Results: We find that the probability of becoming a mother is higher for women who postpone first childbirth due to education and career investment than for women who postpone due to unrealized labour market integration. Conclusions: Educated and economically active women certainly postpone first childbirth in comparison to women who are less educated and who are not working, but they end up with a higher probability of starting a family. Contribution: The article contributes to the academic discussion of circumstances that may lead to birth postponement resulting in higher fertility for younger cohorts in European countries.

  19. Demographic consequences of inbreeding and outbreeding in Arnica montana: A field experiment

    Science.gov (United States)

    Luijten, S.H.; Kery, M.; Oostermeijer, J.G.B.; Den, Nijs H.J.C.M.

    2002-01-01

    1. The genetic constitution of populations may significantly affect demography. Founder populations or isolated remnants may show inbreeding depression, while established populations can be strongly adapted to the local environment. Gene exchange between populations can lead to better performance if heterozygosity levels are restored (heterosis), or to reduced performance if coadapted gene complexes are disrupted (outbreeding depression). 2. Five populations of the self-incompatible perennial Arnica montana (Asteraceae) were analysed for the demographic consequences of inbreeding and of intra- and interpopulation outcrossing, using both small and large populations as donors for the latter. We analysed seed production and seed weight and monitored growth, survival and flowering of offspring introduced as seeds and as 4-week-old seedlings in a 4-year field experiment. 3. Reduced seed set after selfing was probably due to the self-incompatibility system rather than to inbreeding depression. There was a significant increase for seed set after interpopulation crosses, which resulted from the alleviation of low mate availability in one of the small populations. 4. Significant inbreeding depression was observed for growth rates of plants introduced as seedlings. We found significant heterosis for flowering probability of plants introduced as seeds, but for plants introduced as seedlings, heterosis for seedling size and flowering probability was only marginally significant. Outbreeding depression was not observed. 5. The results of this study are important for reinforcement measures in small, remnant populations. Significant differences among populations for all measured fitness components suggest that reinforcement is best achieved using material from several populations. 6. The observed higher survival of seedlings as compared with seeds suggests that it is better to plant individuals than to sow. Sowing, however, is easier and cheaper, and was more likely to eliminate

  20. Computational Modeling of Culture's Consequences

    NARCIS (Netherlands)

    Hofstede, G.J.; Jonker, C.M.; Verwaart, T.

    2010-01-01

    This paper presents an approach to formalize the influence of culture on the decision functions of agents in social simulations. The key components are (a) a definition of the domain of study in the form of a decision model, (b) knowledge acquisition based on a dimensional theory of culture,

  1. Demographic Consequences of Gender Discrimination in China: Simulation Analysis of Policy Options

    Science.gov (United States)

    Quanbao, Jiang; Marcus W., Feldman

    2013-01-01

    The large number of missing females in China, a consequence of gender discrimination, is having and will continue to have a profound effect on the country's population development. In this paper, we analyze the causes of this gender discrimination in terms of institutions, culture and, economy, and suggest public policies that might help eliminate gender discrimination. Using a population simulation model, we study the effect of public policies on the sex ratio at birth and excess female child mortality, and the effect of gender discrimination on China's population development. We find that gender discrimination will decrease China's population size, number of births, and working age population, accelerate population aging and exacerbate the male marriage squeeze. These results provide theoretical support for suggesting that the government enact and implement public policies aimed at eliminating gender discrimination. PMID:24363477

  2. Demographic Consequences of Gender Discrimination in China: Simulation Analysis of Policy Options.

    Science.gov (United States)

    Quanbao, Jiang; Shuzhuo, Li; Marcus W, Feldman

    2011-08-01

    The large number of missing females in China, a consequence of gender discrimination, is having and will continue to have a profound effect on the country's population development. In this paper, we analyze the causes of this gender discrimination in terms of institutions, culture and, economy, and suggest public policies that might help eliminate gender discrimination. Using a population simulation model, we study the effect of public policies on the sex ratio at birth and excess female child mortality, and the effect of gender discrimination on China's population development. We find that gender discrimination will decrease China's population size, number of births, and working age population, accelerate population aging and exacerbate the male marriage squeeze. These results provide theoretical support for suggesting that the government enact and implement public policies aimed at eliminating gender discrimination.

  3. Consequences of Enduring Low Fertility – A German Case StudyDemographic Projections and Implications for Different Policy Fields

    Directory of Open Access Journals (Sweden)

    Martin Bujard

    2015-06-01

    Full Text Available Der Originalbeitrag in deutscher Sprache ist verfügbar unter: Bd. 40 (2015: Ausgewählte deutsche Beiträge.Compared to all other countries in the world, Germany has been a “low-fertility country” for a longer period: the total fertility rate has been below 1.5 for four decades. Being the first to experience this development, a case study of Germany allows analysing the consequences of an enduring birth decline. In Germany, low fertility is also an increasingly big issue in politics as well as science, especially due to its extensive consequences on several policy fields that already become visible. However, the assessment of the consequences differs tremendously when it comes either to its intensity or to the question whether ageing or rather population decline is the more severe problem. Differentiated by these two processes, this article combines demographic analysis with the assessment of the consequences for different policy fields such as pensions, health, the economy, the labour market, culture, the EU, international relations and the party system.For all these policy fields, the consequences are serious, and partly ambivalent but overall negative. The occurrence of the consequences and the different policy options how to deal with these consequences differ considerably between the policy fields. Ageing is a more severe problem than shrinking, because the severe changes in the age structure in the social security system that will take place until 2040 apply to most Germans and are inevitable. On the other hand, the population decline can still be avoided demographically and does not affect all inhabitants negatively. Regarding the consequences of a declining population, one has to differentiate between an individual and a national perspective. National consequences are rather negative due to a decline of international influence and power, especially within the European Union. The study also demonstrates that the long

  4. Demographic consequences of greater clonal than sexual reproduction in Dicentra canadensis.

    Science.gov (United States)

    Lin, Chia-Hua; Miriti, Maria N; Goodell, Karen

    2016-06-01

    Clonality is a widespread life history trait in flowering plants that may be essential for population persistence, especially in environments where sexual reproduction is unpredictable. Frequent clonal reproduction, however, could hinder sexual reproduction by spatially aggregating ramets that compete with seedlings and reduce inter-genet pollination. Nevertheless, the role of clonality in relation to variable sexual reproduction in population dynamics is often overlooked. We combined population matrix models and pollination experiments to compare the demographic contributions of clonal and sexual reproduction in three Dicentra canadensis populations, one in a well-forested landscape and two in isolated forest remnants. We constructed stage-based transition matrices from 3 years of census data to evaluate annual population growth rates, λ. We used loop analysis to evaluate the relative contribution of different reproductive pathways to λ. Despite strong temporal and spatial variation in seed set, populations generally showed stable growth rates. Although we detected some pollen limitation of seed set, manipulative pollination treatments did not affect population growth rates. Clonal reproduction contributed significantly more than sexual reproduction to population growth in the forest remnants. Only at the well-forested site did sexual reproduction contribute as much as clonal reproduction to population growth. Flowering plants were more likely to transition to a smaller size class with reduced reproductive potential in the following year than similarly sized nonflowering plants, suggesting energy trade-offs between sexual and clonal reproduction at the individual level. Seed production had negligible effects on growth and tuber production of individual plants. Our results demonstrate that clonal reproduction is vital for population persistence in a system where sexual reproduction is unpredictable. The bias toward clonality may be driven by low fitness returns

  5. Consequence Reasoning in Multilevel Flow Modelling

    DEFF Research Database (Denmark)

    Zhang, Xinxin; Lind, Morten; Ravn, Ole

    2013-01-01

    Consequence reasoning is a major element for operation support system to assess the plant situations. The purpose of this paper is to elaborate how Multilevel Flow Models can be used to reason about consequences of disturbances in complex engineering systems. MFM is a modelling methodology...... for representing process knowledge for complex systems. It represents the system by using means-end and part-whole decompositions, and describes not only the purposes and functions of the system but also the causal relations between them. Thus MFM is a tool for causal reasoning. The paper introduces MFM modelling...... syntax and gives detailed reasoning formulas for consequence reasoning. The reasoning formulas offers basis for developing rule-based system to perform consequence reasoning based on MFM, which can be used for alarm design, risk monitoring, and supervision and operation support system design....

  6. China’s “One-child family” demographic policy - Analyzing the consequences of the measures taken to confine the demographic growth of China

    Directory of Open Access Journals (Sweden)

    Pascu, M.L.

    2011-01-01

    Full Text Available The so called “one-child policy” has brought economic benefits in China for the three decades since it was enforced, but it has also brought a series of disadvantages with consequences in the near future: increase of the dependency ratio in China with the accentuation of the population ageing phenomenon and the occurrence of disparities in the sex ratio that will lead to special social problems. Some experts believe that the simplistic reasoning behind the “one-child policy” might be responsible for the next demographic crisis. On one hand, the number of Chinese citizens is still growing. On the other hand China faces a very rapid aging of the population.

  7. Three demographic consequences of gender-specific behavior pattern: The case of Serbia

    Directory of Open Access Journals (Sweden)

    Šobot Ankica

    2012-01-01

    Full Text Available The focus point in this paper referes to three issues of demographic development in Serbia presented from the gender perspective. Feminization, mortality in men and low reproductive norms are analyzed as effects of relevant behavior of both sexes. This choice is the result of earlier analyses of gender socio-demographic characteristics as well as the researches of demographic phenomena from the perspective of gender roles and gender relations. The gender aspect, as a cognitive concept, implies the importance of the female and male behavior pattern in understanding demographic structures, processes and phenomena. The theoretical foundation was found in the anthropological character of contemporary demography which focuses on the individual’s behavior in the context of interactive relations with the concrete environment. In the context of a complex deterministic basis and interactive connection of various factors, gender roles and gender relations represent a relative segment of social dimension of various demographic issues. Feminization of the middle-aged and older population emphasizes the importance of female perspective, taking into consideration space diversity. Feminization is most intensive in Belgrade. Among the middle-aged women there is a higher proportion of tertiary educated and divorced, and less share of the economically independent, in relation to the remaining region of Central Serbia. As regards older women, irrespective of spatial distribution, widowhood, unfavorable education characteristics, lower economic activity and greater economic dependency are important matters. The issue of retirement has specific importance, and should be solved in the context of educated and socio-professional characteristics of women, in order to promote their social position and gender equality. A shorter life span of the male population requires recognizing specific mortality factors of the middle-aged and older males, in order to eliminate the

  8. Modeling the Temporal Nature of Human Behavior for Demographics Prediction

    DEFF Research Database (Denmark)

    Felbo, Bjarke; Sundsøy, Pål; Pentland, Alex

    2017-01-01

    Mobile phone metadata is increasingly used for humanitarian purposes in developing countries as traditional data is scarce. Basic demographic information is however often absent from mobile phone datasets, limiting the operational impact of the datasets. For these reasons, there has been a growing...... interest in predicting demographic information from mobile phone metadata. Previous work focused on creating increasingly advanced features to be modeled with standard machine learning algorithms. We here instead model the raw mobile phone metadata directly using deep learning, exploiting the temporal...... on both age and gender prediction using only the temporal modality in mobile metadata. We finally validate our method on low activity users and evaluate the modeling assumptions....

  9. Hyperstate matrix models : extending demographic state spaces to higher dimensions

    NARCIS (Netherlands)

    Roth, G.; Caswell, H.

    2016-01-01

    1. Demographic models describe population dynamics in terms of the movement of individuals among states (e.g. size, age, developmental stage, parity, frailty, physiological condition). Matrix population models originally classified individuals by a single characteristic. This was enlarged to two

  10. A Computational Model of Selection by Consequences

    Science.gov (United States)

    McDowell, J. J.

    2004-01-01

    Darwinian selection by consequences was instantiated in a computational model that consisted of a repertoire of behaviors undergoing selection, reproduction, and mutation over many generations. The model in effect created a digital organism that emitted behavior continuously. The behavior of this digital organism was studied in three series of…

  11. Demographic Changes and Their Spatial-Settlement Consequences: Lessons from East Germany and Hungary

    Directory of Open Access Journals (Sweden)

    Tibor Kovács

    2016-12-01

    Full Text Available Demographic shrinkage has created ‘new’ challenges in the spatial and urban development of the developed world and its semi periphery for nearly three and a half decades and it requires a different way of thinking and different solutions as well compared to previous development practices. Theoretical research and development activities in practice are further aggravated by the mono-minded mentality of society, economy and politics fallen a victim to charms of ‘growth’; the slow recognition of the fact of spatial-urban shrinkage and the reluctance to deal with the problem (especially on the semi periphery. In this paper I would like to outline the settlement and spatial problems of demographic shrinkage and suggest certain theoretical solutions being aware of the fact that there is no universal solution for shrinkage; each and every settlement has to find and carry out their own solution – emphasising the mobilisation of the endogenous resources of the given region or settlement.

  12. Demographic model of the Neolithic transition in Central Europe

    Directory of Open Access Journals (Sweden)

    Patrik Galeta

    2009-12-01

    Full Text Available Several recent lines of evidence indicate more intensive contact between LBK farmers and indigenous foragers in Central Europe (5600–5400 calBC. Strong continuity has been identified between Mesolithic and Neolithic material cultures; faunal assemblages, and isotopic analyses of diet have revealed a greater role of hunting in LBK communities; genetic analyses have suggested that the modern Central European gene pool is mainly of Palaeolithic origin. Surprisingly little attention has been paid to demographic aspects of the Neolithic transition. In our study, demographic simulations were performed to assess the demographic conditions that would allow LBK farmers to spread across central Europe without any admixture with Mesolithic foragers. We constructed a stochastic demographic model of changes in farming population size. Model parameters were constrained by data from human demography, archaeology, and human ecology. Our results indicate that the establishment of farming communities in Central Europe without an admixture with foragers was highly improbable. The demographic conditions necessary for colonization were beyond the potential of the Neolithic population. Our study supports the integrationists’ view of the Neolithic transition in Central Europe.

  13. A computational model of selection by consequences.

    OpenAIRE

    McDowell, J J

    2004-01-01

    Darwinian selection by consequences was instantiated in a computational model that consisted of a repertoire of behaviors undergoing selection, reproduction, and mutation over many generations. The model in effect created a digital organism that emitted behavior continuously. The behavior of this digital organism was studied in three series of computational experiments that arranged reinforcement according to random-interval (RI) schedules. The quantitative features of the model were varied o...

  14. Updates to the Demographic and Spatial Allocation Models to ...

    Science.gov (United States)

    EPA announced the availability of the draft report, Updates to the Demographic and Spatial Allocation Models to Produce Integrated Climate and Land Use Scenarios (ICLUS) for a 30-day public comment period. The ICLUS version 2 (v2) modeling tool furthered land change modeling by providing nationwide housing development scenarios up to 2100. ICLUS V2 includes updated population and land use data sets and addressing limitations identified in ICLUS v1 in both the migration and spatial allocation models. The companion user guide describes the development of ICLUS v2 and the updates that were made to the original data sets and the demographic and spatial allocation models. [2017 UPDATE] Get the latest version of ICLUS and stay up-to-date by signing up to the ICLUS mailing list. The GIS tool enables users to run SERGoM with the population projections developed for the ICLUS project and allows users to modify the spatial allocation housing density across the landscape.

  15. [The consequences of the demographic revolution and of the aging of society: restructuring the age groups and modifying intergenerational relations].

    Science.gov (United States)

    Loriaux, M

    1995-01-01

    The consequences of demographic aging in developed societies are examined. The author notes that "demographic aging has intensified over the last decades, bringing with it a significant modification in relationships between age groups and the sexes.... These changes in demographic structures bring with them the reorganization in intergenerational relations, the most spectacular instance of which...[is] the coexistence at the same time and in the same place of four or five generations of direct descendants." The author develops the hypothesis that a new attitude toward old age is needed in which "the social status of the elderly must be reinstated, and everything must be brought into play to encourage the integration of different age groups and intergenerational solidarity, so as to arrive in the best possible conditions at what [can be termed] the 'era of old age'...which will accompany the coming of the post-industrial society with its orientation toward the mass production of leisure and of services." (SUMMARY IN ENG AND SPA) excerpt

  16. The modelling of economic consequences in COSYMA

    International Nuclear Information System (INIS)

    Faude, D.

    1991-01-01

    A new model for assessing the economic consequences of accidents, called COCO-1 (Cost of Consequences Off-site) has been developed jointly by NRPB and KfK under the CEC MARIA programme. This paper describes the way in which this model, together with other options, has been implemented in the ECONOMICS module of COSYMA. For consistency with the other parts of COSYMA, the coding of the ECONOMICS module is flexible: in several areas, alternative calculational methods are available and the user may select the method by which a particular cost is calculated. To some extent, economic models other than the COCO-1 model may be applied. There are two types of input data in the ECONOMICS module. These are (1) data from preceding COSYMA modules which quantify the magnitude and distribution of health effects and the impact of countermeasures, and (2) economic data, in terms of costs per unit quantity, to convert the preceding data into monetary values. The structure of the module has been determined by the form and availability of the input data, and the general structure of COSYMA. Details of the method of calculation, and the necessary input data, are discussed, for calculation of the economic consequences of the countermeasures considered in COSYMA (evacuation, relocation, sheltering, decontamination and food bans) and for early and late health effects

  17. The demographic consequences of mutualism: ants increase host-plant fruit production but not population growth

    Science.gov (United States)

    Kevin Ford; Joshua H. Ness; Judith L. Bronstein; William F. Morris

    2015-01-01

    The impact of mutualists on a partner’s demography depends on how they affect the partner’s multiple vital rates and how those vital rates, in turn, affect population growth. However, mutualism studies rarely measure effects on multiple vital rates or integrate them to assess the ultimate impact on population growth. We used vital rate data, population models and...

  18. CHANGES IN LAND USE AS CONSEQUENCE OF DEMOGRAPHIC TRANSFORMATIONS OF RURAL TERRITORIES OF THE VOLGOGRAD REGION

    Directory of Open Access Journals (Sweden)

    N. V. Vishnyakov

    2016-01-01

    Full Text Available Aim. Analysis of the population dynamics and changes in the share of arable land in the structure of land use separate territory for several historical periods, and to determine the causes of these changes. Methods. Studies have used forwarding, statistical methods, and the method of cartographic modeling and retrospective analysis. Results. Analysis of the results of the population census allows speaking about the general negative dynamics in the rural population of the Volgograd region in general and river basin Bolshaya Golubaya in particular. Historical and cartographic analysis has shown the dependence of the arable lands of the number of residents on the territory residents. In addition, the population of the territory is significantly affected by soil fertility. Main conclusions. The population of the river basin Bolshaya Golubaya over the past hundred years have steadily decreased, as due to various socio-economic reasons, such as consolidation of rural settlements, the planned destruction of farm system, moving people into the city, and due to the difficult climatic conditions for farming: poor soil fertility, high degree of erosion areas, poor soil conditions of the territory.

  19. Analytical properties of a three-compartmental dynamical demographic model

    Science.gov (United States)

    Postnikov, E. B.

    2015-07-01

    The three-compartmental demographic model by Korotaeyv-Malkov-Khaltourina, connecting population size, economic surplus, and education level, is considered from the point of view of dynamical systems theory. It is shown that there exist two integrals of motion, which enables the system to be reduced to one nonlinear ordinary differential equation. The study of its structure provides analytical criteria for the dominance ranges of the dynamics of Malthus and Kremer. Additionally, the particular ranges of parameters enable the derived general ordinary differential equations to be reduced to the models of Gompertz and Thoularis-Wallace.

  20. PopPlanner: Visually constructing demographic models for simulation

    Directory of Open Access Journals (Sweden)

    Gregory Bruce Ewing

    2015-04-01

    Full Text Available Currently there are a number of coalescent simulation programs that support a wide range of features, such as arbitrary demographic models, migration, and sub structure. Defining the model is done typically with either text files or command line switches. Although this has proven to be a powerful method of defining models of high complexity, it is often error prone and difficult to read without familiarity both with command lines and the program in question. A intuitive GUI based population structure program that can both read and write applicable command lines would dramatically simplify the construction, modification, and error checking of such models by a wider user base.Results: PopPlanner is a tool to both construct and inspect complicated demographic models visually with a GUI where the user’s primary interaction is through mouse gestures. Because of their popularity, we focus on ms and by extension msms, command line coalescent simulation programs. Our program can be used to find errors with existing command lines, or to build original command lines. Furthermore the graphical output supports a number of editing and output features including export of publication quality figures.

  1. Toward linking demographic and economic models for impact assessment

    International Nuclear Information System (INIS)

    Williams, C.A.; Meenan, C.D.

    1991-01-01

    One of the objectives of the Yucca Mountain Project, in Southern Nevada, is to evaluate the effects of the development of a high-level nuclear waste repository. As described in the Section 175 Report to the Congress of the US, the temporal scope of this repository project encompasses approximately 70 years and includes four phases: Site characterization and licensing, construction, operation, and closure and decommissioning. If retrieval of the waste were to be required, the temporal scope of the repository project could be extended to approximately 100 years. The study of the potential socioeconomic effects of this project is the foundation for this paper. This paper focuses on the economic and demographic aspects and a possible method to interface the two. First, the authors briefly discuss general socioeconomic modeling theory from a county level view point, as well as methods for the apportionment of county level data to sub-county areas. Next, the authors describe the unique economic and demographic conditions which exist in Nevada at both the state and county levels. Finally, the authors evaluate a possible procedure for analyzing repository effects at a sub-county level; this involves discussion of an interface linking the economic and demographic aspects, which is based on the reconciliation of supply and demand for labor. The authors conclude that the basis for further model development may rely on the interaction of supply and demand to produce change in wage rates. These changes in expected wages should be a justification for allocating economic migrants (who may respond to Yucca Mountain Project development) into various communities

  2. Modeling the economic consequences of LWR accidents

    International Nuclear Information System (INIS)

    Burke, R.P.; Aldrich, D.C.; Rasmussen, N.C.

    1984-01-01

    Models to be used for analyses of economic risks from events which may occur during LWR plant operation are developed in this study. The models include capabilities to estimate both onsite and offsite costs of LWR events ranging from routine plant outages to severe core-melt accidents resulting in large releases of radioactive material to the environment. The models can be used by both the nuclear power industry and regulatory agencies in cost-benefit analyses for decisionmaking purposes. The newly developed economic consequence models are applied in an example to estimate the economic risks from operation of the Surry Unit 2 plant. The analyses indicate that economic risks from US LWR operation, in contrast to public health risks, are dominated by relatively high-frequency forced outage events. Even for severe (e.g., core-melt) accidents, expected offsite costs are less than expected onsite costs for the Surry site. The implications of these conclusions for nuclear power plant operation and regulation are discussed

  3. Environmental versus demographic variability in stochastic predator–prey models

    International Nuclear Information System (INIS)

    Dobramysl, U; Täuber, U C

    2013-01-01

    In contrast to the neutral population cycles of the deterministic mean-field Lotka–Volterra rate equations, including spatial structure and stochastic noise in models for predator–prey interactions yields complex spatio-temporal structures associated with long-lived erratic population oscillations. Environmental variability in the form of quenched spatial randomness in the predation rates results in more localized activity patches. Our previous study showed that population fluctuations in rare favorable regions in turn cause a remarkable increase in the asymptotic densities of both predators and prey. Very intriguing features are found when variable interaction rates are affixed to individual particles rather than lattice sites. Stochastic dynamics with demographic variability in conjunction with inheritable predation efficiencies generate non-trivial time evolution for the predation rate distributions, yet with overall essentially neutral optimization. (paper)

  4. Putting the "ecology" into environmental flows: ecological dynamics and demographic modelling.

    Science.gov (United States)

    Shenton, Will; Bond, Nicholas R; Yen, Jian D L; Mac Nally, Ralph

    2012-07-01

    There have been significant diversions of water from rivers and streams around the world; natural flow regimes have been perturbed by dams, barriers and excessive extractions. Many aspects of the ecological 'health' of riverine systems have declined due to changes in water flows, which has stimulated the development of thinking about the maintenance and restoration of these systems, which we refer to as environmental flow methodologies (EFMs). Most existing EFMs cannot deliver information on the population viability of species because they: (1) use habitat suitability as a proxy for population status; (2) use historical time series (usually of short duration) to forecast future conditions and flow sequences; (3) cannot, or do not, handle extreme flow events associated with climate variability; and (4) assume process stationarity for flow sequences, which means the past sequences are treated as good indicators of the future. These assumptions undermine the capacity of EFMs to properly represent risks associated with different flow management options; assumption (4) is untenable given most climate-change predictions. We discuss these concerns and advocate the use of demographic modelling as a more appropriate tool for linking population dynamics to flow regime change. A 'meta-species' approach to demographic modelling is discussed as a useful step from habitat based models towards modelling strategies grounded in ecological theory when limited data are available on flow-demographic relationships. Data requirements of demographic models will undoubtedly expose gaps in existing knowledge, but, in so doing, will strengthen future efforts to link changes in river flows with their ecological consequences.

  5. Putting the "Ecology" into Environmental Flows: Ecological Dynamics and Demographic Modelling

    Science.gov (United States)

    Shenton, Will; Bond, Nicholas R.; Yen, Jian D. L.; Mac Nally, Ralph

    2012-07-01

    There have been significant diversions of water from rivers and streams around the world; natural flow regimes have been perturbed by dams, barriers and excessive extractions. Many aspects of the ecological `health' of riverine systems have declined due to changes in water flows, which has stimulated the development of thinking about the maintenance and restoration of these systems, which we refer to as environmental flow methodologies (EFMs). Most existing EFMs cannot deliver information on the population viability of species because they: (1) use habitat suitability as a proxy for population status; (2) use historical time series (usually of short duration) to forecast future conditions and flow sequences; (3) cannot, or do not, handle extreme flow events associated with climate variability; and (4) assume process stationarity for flow sequences, which means the past sequences are treated as good indicators of the future. These assumptions undermine the capacity of EFMs to properly represent risks associated with different flow management options; assumption (4) is untenable given most climate-change predictions. We discuss these concerns and advocate the use of demographic modelling as a more appropriate tool for linking population dynamics to flow regime change. A `meta-species' approach to demographic modelling is discussed as a useful step from habitat based models towards modelling strategies grounded in ecological theory when limited data are available on flow-demographic relationships. Data requirements of demographic models will undoubtedly expose gaps in existing knowledge, but, in so doing, will strengthen future efforts to link changes in river flows with their ecological consequences.

  6. Influence of demographic changes on the impact of vaccination against varicella and herpes zoster in Germany - a mathematical modelling study.

    Science.gov (United States)

    Horn, Johannes; Damm, Oliver; Greiner, Wolfgang; Hengel, Hartmut; Kretzschmar, Mirjam E; Siedler, Anette; Ultsch, Bernhard; Weidemann, Felix; Wichmann, Ole; Karch, André; Mikolajczyk, Rafael T

    2018-01-09

    Epidemiological studies suggest that reduced exposure to varicella might lead to an increased risk for herpes zoster (HZ). Reduction of exposure to varicella is a consequence of varicella vaccination but also of demographic changes. We analyzed how the combination of vaccination programs and demographic dynamics will affect the epidemiology of varicella and HZ in Germany over the next 50 years. We used a deterministic dynamic compartmental model to assess the impact of different varicella and HZ vaccination strategies on varicella and HZ epidemiology in three demographic scenarios, namely the projected population for Germany, the projected population additionally accounting for increased immigration as observed in 2015/2016, and a stationary population. Projected demographic changes alone result in an increase of annual HZ cases by 18.3% and a decrease of varicella cases by 45.7% between 1990 and 2060. Independently of the demographic scenario, varicella vaccination reduces the cumulative number of varicella cases until 2060 by approximately 70%, but also increases HZ cases by 10%. Unlike the currently licensed live attenuated HZ vaccine, the new subunit vaccine candidate might completely counteract this effect. Relative vaccine effects were consistent across all demographic scenarios. Demographic dynamics will be a major determinant of HZ epidemiology in the next 50 years. While stationary population models are appropriate for assessing vaccination impact, models incorporating realistic population structures allow a direct comparison to surveillance data and can thus provide additional input for immunization decision-making and resource planning.

  7. Modeling atmospheric dispersion for reactor accident consequence evaluation

    International Nuclear Information System (INIS)

    Alpert, D.J.; Gudiksen, P.H.; Woodard, K.

    1982-01-01

    Atmospheric dispersion models are a central part of computer codes for the evaluation of potential reactor accident consequences. A variety of ways of treating to varying degrees the many physical processes that can have an impact on the predicted consequences exists. The currently available models are reviewed and their capabilities and limitations, as applied to reactor accident consequence analyses, are discussed

  8. Empirical Succession Mapping and Data Assimilation to Constrain Demographic Processes in an Ecosystem Model

    Science.gov (United States)

    Kelly, R.; Andrews, T.; Dietze, M.

    2015-12-01

    Shifts in ecological communities in response to environmental change have implications for biodiversity, ecosystem function, and feedbacks to global climate change. Community composition is fundamentally the product of demography, but demographic processes are simplified or missing altogether in many ecosystem, Earth system, and species distribution models. This limitation arises in part because demographic data are noisy and difficult to synthesize. As a consequence, demographic processes are challenging to formulate in models in the first place, and to verify and constrain with data thereafter. Here, we used a novel analysis of the USFS Forest Inventory Analysis to improve the representation of demography in an ecosystem model. First, we created an Empirical Succession Mapping (ESM) based on ~1 million individual tree observations from the eastern U.S. to identify broad demographic patterns related to forest succession and disturbance. We used results from this analysis to guide reformulation of the Ecosystem Demography model (ED), an existing forest simulator with explicit tree demography. Results from the ESM reveal a coherent, cyclic pattern of change in temperate forest tree size and density over the eastern U.S. The ESM captures key ecological processes including succession, self-thinning, and gap-filling, and quantifies the typical trajectory of these processes as a function of tree size and stand density. Recruitment is most rapid in early-successional stands with low density and mean diameter, but slows as stand density increases; mean diameter increases until thinning promotes recruitment of small-diameter trees. Strikingly, the upper bound of size-density space that emerges in the ESM conforms closely to the self-thinning power law often observed in ecology. The ED model obeys this same overall size-density boundary, but overestimates plot-level growth, mortality, and fecundity rates, leading to unrealistic emergent demographic patterns. In particular

  9. Costs of fear: Behavioral and life-history responses to risk and their demographic consequences vary across species

    Science.gov (United States)

    LaManna, Joseph A.; Martin, Thomas E.

    2016-01-01

    Behavioural responses to reduce predation risk might cause demographic ‘costs of fear’. Costs differ among species, but a conceptual framework to understand this variation is lacking. We use a life-history framework to tie together diverse traits and life stages to better understand interspecific variation in responses and costs. We used natural and experimental variation in predation risk to test phenotypic responses and associated demographic costs for 10 songbird species. Responses such as increased parental attentiveness yielded reduced development time and created benefits such as reduced predation probability. Yet, responses to increased risk also created demographic costs by reducing offspring production in the absence of direct predation. This cost of fear varied widely across species, but predictably with the probability of repeat breeding. Use of a life-history framework can aid our understanding of potential demographic costs from predation, both from responses to perceived risk and from direct predation mortality.

  10. Satisfaction with life in adults with Marfan syndrome (MFS): associations with health-related consequences of MFS, pain, fatigue, and demographic factors.

    Science.gov (United States)

    Velvin, Gry; Bathen, Trine; Rand-Hendriksen, Svend; Geirdal, Amy Østertun

    2016-07-01

    The objective with this study was to explore satisfaction with life (SWL) among adults with Marfan syndrome (MFS) compared to the general Norwegian population and other patient groups and further to examine the associations between SWL and demographic factors, contact with social and health services, MFS-related health problems, chronic pain, and fatigue. This is a cross-sectional study with postal questionnaire, including the Satisfaction with Life Scale (SWLS), questions on demographic factors, health-related aspects of MFS, and validated instruments measuring chronic pain (Standardized Nordic Questionnaire) and fatigue (Fatigue Severity Scale). One hundred and seventeen adults with MFS were invited to participate, and 73 (62 %) participated. The SWLS mean score in adults with MFS was significantly lower than that reported for the general Norwegian population, but similar to or higher than that reported for other patient groups. Only fatigue, aortic dissection, and having regular contact with psychologist showed significant unique contribution to the SWLS score in the hierarchical multiple linear analyses. The total variance explained by the model was 45.2 % p ≤ 0.000, confirming that the combination of independent variables significantly predicted SWLS. The results reflect that MFS influences people's SWL and that particularly severe fatigue, aortic dissection, and psychological aspects are associated with lower SWL. This is important to take into account in the clinical work with people with MFS. Further investigation is needed, especially on larger sample groups. Studies with combination of qualitative and quantitative approaches are recommended to obtain more comprehensive and accurate knowledge about the consequences of MFS on satisfaction with life.

  11. Demographic consequences of climate change and land cover help explain a history of extirpations and range contraction in a declining snake species.

    Science.gov (United States)

    Pomara, Lars Y; LeDee, Olivia E; Martin, Karl J; Zuckerberg, Benjamin

    2014-07-01

    Developing conservation strategies for threatened species increasingly requires understanding vulnerabilities to climate change, in terms of both demographic sensitivities to climatic and other environmental factors, and exposure to variability in those factors over time and space. We conducted a range-wide, spatially explicit climate change vulnerability assessment for Eastern Massasauga (Sistrurus catenatus), a declining endemic species in a region showing strong environmental change. Using active season and winter adult survival estimates derived from 17 data sets throughout the species' range, we identified demographic sensitivities to winter drought, maximum precipitation during the summer, and the proportion of the surrounding landscape dominated by agricultural and urban land cover. Each of these factors was negatively associated with active season adult survival rates in binomial generalized linear models. We then used these relationships to back-cast adult survival with dynamic climate variables from 1950 to 2008 using spatially explicit demographic models. Demographic models for 189 population locations predicted known extant and extirpated populations well (AUC = 0.75), and models based on climate and land cover variables were superior to models incorporating either of those effects independently. These results suggest that increasing frequencies and severities of extreme events, including drought and flooding, have been important drivers of the long-term spatiotemporal variation in a demographic rate. We provide evidence that this variation reflects nonadaptive sensitivity to climatic stressors, which are contributing to long-term demographic decline and range contraction for a species of high-conservation concern. Range-wide demographic modeling facilitated an understanding of spatial shifts in climatic suitability and exposure, allowing the identification of important climate refugia for a dispersal-limited species. Climate change vulnerability

  12. Models of quark bags and their consequences

    International Nuclear Information System (INIS)

    Bogolubov, P.N.

    1977-01-01

    The development of the first Dubna Quark Bag and the results obtained in this way are considered. The idea of the first Dubna Quark Bag is as follows: baryons are constructed of three quarks measons are constructed of two quarks, and each quark is interpreted as the Dirac particle which moves in a scalar square well. The so-called quasiindependent quark model is considered too. It is a simple quark model based on an analogy with the shell model for nuclei. The quarks are considered as moving in an arbitrary radially-symmetric field, and their one-particle wave function satisfies the usual Dirac equation. Such quark model can give at least the same results as the relativistic bag model. A possibility exists to improve the results of the relativistic quark model with the oscillator interaction between quarks. The results of the MIT-Bag model and the quasiindependent quark model coincide

  13. Modeling evolutionary games in populations with demographic structure

    DEFF Research Database (Denmark)

    Li, Xiang-Yi; Giaimo, Stefano; Baudisch, Annette

    2015-01-01

    interactions, but usually omits life history and the demographic structure of the population. Here we show how an integration of both aspects can substantially alter the underlying evolutionary dynamics. We study the replicator dynamics of strategy interactions in life stage structured populations. Individuals...

  14. Modelling fog in probabilistic consequence assessment

    International Nuclear Information System (INIS)

    Underwood, B.Y.

    1993-02-01

    Earlier work examined the potential influence of foggy weather conditions on the probabilistic assessment of the consequences of accidental releases of radioactive material to the atmosphere (PCA), in particular the impact of a fraction of the released aerosol becoming incorporated into droplets. A major uncertainty emerging from the initial scoping study concerned estimation of the fraction of the released material that would be taken up into droplets. An objective is to construct a method for handling in a PCA context the effect of fog on deposition, basing the method on the experience gained from prior investigations. There are two aspects to explicitly including the effect of fog in PCA: estimating the probability of occurrence of various types of foggy condition and calculating the impact on the conventional end-points of consequence assessment. For the first, a brief outline is given of the use of meteorological data by PCA computer codes, followed by a discussion of some routinely-recorded meteorological parameters that are pertinent to fog, such as the presentweather code and horizontal visibility. Four stylized scenarios are defined to cover a wide range of situations in which particle growth by uptake of water may have an important impact on deposition. A description is then given of the way in which routine meteorological data could be used to flag the presence of each of these conditions in the meteorological data file used by the PCA code. The approach developed to calculate the impact on deposition is pitched at a level of complexity appropriate to the PCA context and reflects the physical constraints of the system and accounts for the specific characteristics of the released aerosol. (Author)

  15. Antecedents and Consequences of Business Model Innovation

    DEFF Research Database (Denmark)

    Waldner, Florian; Poetz, Marion; Grimpe, Christoph

    2015-01-01

    evidence seems to be confined to firm-level antecedents and pays little attention to the impact of industry structure. This study investigates how different stages of an industry’s life cycle and levels of industry competition affect firms’ business model innovation, and how such innovation translates...... into innovation performance. Based on a cross-industry sample of 1,242 Austrian firms, we introduce a unique measure for the degree of innovation in a firm’s business model. The results indicate that the degree of business model innovation is highest toward the beginning of an industry life cycle, that is......What makes firms innovate their business models? Why do they engage in innovating how they create, deliver, and capture value? And how does such innovation translate into innovation performance? Despite the importance of business model innovation for achieving competitive advantage, existing...

  16. Demographic situation in the Kaluga region for 1976-1992. Possible consequences of the Chernobyl NPP accident

    International Nuclear Information System (INIS)

    Omel'chenko, V.N.; Kurochkina, O.I.; Kostina, M.A.; Sidenko, L.G.

    1993-01-01

    The paper studies the demographic situation in different areas of the Kaluga region contaminated as a result of the Chernobyl accident, during 1976-1992. The following indices received the particular attention: the composition of population, size of population, birth rate, mortality, child mortality. It is shown that during the investigated period no variations of the size of population, of the mortality and of the increment of population resulted from the Chernobyl accident were detected

  17. Spatial demographic models to inform conservation planning of golden eagles in renewable energy landscapes

    Science.gov (United States)

    Wiens, J. David; Schumaker, Nathan H.; Inman, Richard D.; Esque, Todd C.; Longshore, Kathleen M.; Nussear, Kenneth E

    2017-01-01

    Spatial demographic models can help guide monitoring and management activities targeting at-risk species, even in cases where baseline data are lacking. Here, we provide an example of how site-specific changes in land use and anthropogenic stressors can be incorporated into a spatial demographic model to investigate effects on population dynamics of Golden Eagles (Aquila chrysaetos). Our study focused on a population of Golden Eagles exposed to risks associated with rapid increases in renewable energy development in southern California, U.S.A. We developed a spatially explicit, individual-based simulation model that integrated empirical data on demography of Golden Eagles with spatial data on the arrangement of nesting habitats, prey resources, and planned renewable energy development sites. Our model permitted simulated eagles of different stage-classes to disperse, establish home ranges, acquire prey resources, prospect for breeding sites, and reproduce. The distribution of nesting habitats, prey resources, and threats within each individual's home range influenced movement, reproduction, and survival. We used our model to explore potential effects of alternative disturbance scenarios, and proposed conservation strategies, on the future distribution and abundance of Golden Eagles in the study region. Results from our simulations suggest that probable increases in mortality associated with renewable energy infrastructure (e.g., collisions with wind turbines and vehicles, electrocution on power poles) could have negative consequences for population trajectories, but that site-specific conservation actions could reduce the magnitude of negative effects. Our study demonstrates the use of a flexible and expandable modeling framework to incorporate spatially dependent processes when determining relative effects of proposed management options to Golden Eagles and their habitats.

  18. Evaluation of habitat suitability models for forest passerines using demographic data

    Science.gov (United States)

    Chadwick D. Rittenhouse; Frank R., III Thompson; William D. Dijak; Joshua J. Millspaugh; Richard L. Clawson

    2010-01-01

    Habitat suitability is often used as a surrogate for demographic responses (i.e., abundance, survival, fecundity, or population viability) in the application of habitat suitability index (HSI) models. Whether habitat suitability actually relates to demographics, however, has rarely been evaluated. We validated HSI models of breeding habitat suitability for wood thrush...

  19. RadCon: A Radiological Consequences Model

    International Nuclear Information System (INIS)

    Crawford, J.; Domel, R.U.

    2000-05-01

    RadCon estimates the dose received by user selected groups in the population from an accidental release of radionuclides to the environment. The exposure pathways considered are external exposure from the cloud and ground and internal exposure from inhalation and ingestion of contaminated food. Atmospheric dispersion modelling is carried out externally to RadCon.Given a two dimensional time varying air and ground concentration of radioactive elements, RadCon allows the user to: view the air and ground concentration over the affected area, select optional parameters and calculate the dose to people,display the results to the user, and change the parameter values. RadCon offers two user interfaces: 1) the standard graphical user interface which is started using Java DoseApp at the command line, or by setting up a shortcut to this command (particularly when RadCon is installed on a PC) and 2) the text based interface used to generate information for the model inter-comparison exercise . This is initiated using Java BIOMASS at the command line, or an equivalent shortcut. The text based interface was developed for research purposes and is not generally available. Appendices A, B and C provide a summary of instructions on setting up RadCon. This will generally be carried out by the computer support personnel

  20. Socio-demographic characteristics and psychosocial consequences of sickle cell disease: the case of patients in a public hospital in Ghana.

    Science.gov (United States)

    Adzika, Vincent A; Glozah, Franklin N; Ayim-Aboagye, Desmond; Ahorlu, Collins S K

    2017-01-31

    Sickle cell disease (SCD) is of major public health concern globally, with majority of patients living in Africa. Despite its relevance, there is a dearth of research to determine the socio-demographic distribution and psychosocial impact of SCD in Ghana. The objective of this study was to examine the socio-demographic distribution and psychosocial consequences of SCD among patients in Ghana and to assess their quality of life and coping mechanisms. A cross-sectional research design was used that involved the completion of questionnaires on socio-demographic characteristics, quality of life, coping mechanisms, anxiety and depression. Participants were 387 male and female patients attending a sickle cell clinic in a public hospital. Results showed that majority of the patients were single, female, less than 39 years old and had attained secondary school level of education or less. Also, patients were more satisfied by the presence of love, friends and relatives as well as home, community and neighbourhood environment. While pains of varied nature and severity were the major reasons for attending hospital in SCD condition, going to the hospital as well as having faith in God was the most frequently reported mechanisms for coping with an unbearable SCD attacks. Results of multiple regression analysis showed that some socio-demographic and quality of life indicators had strong associations with anxiety and/or depression. It is recommended that a holistic intervention strategy incorporating psychosocial dimensions should be considered in the treatment and management of SCD.

  1. Apply Functional Modelling to Consequence Analysis in Supervision Systems

    DEFF Research Database (Denmark)

    Zhang, Xinxin; Lind, Morten; Gola, Giulio

    2013-01-01

    This paper will first present the purpose and goals of applying functional modelling approach to consequence analysis by adopting Multilevel Flow Modelling (MFM). MFM Models describe a complex system in multiple abstraction levels in both means-end dimension and whole-part dimension. It contains...... consequence analysis to practical or online applications in supervision systems. It will also suggest a multiagent solution as the integration architecture for developing tools to facilitate the utilization results of functional consequence analysis. Finally a prototype of the multiagent reasoning system...... causal relations between functions and goals. A rule base system can be developed to trace the causal relations and perform consequence propagations. This paper will illustrate how to use MFM for consequence reasoning by using rule base technology and describe the challenges for integrating functional...

  2. Evaluation of atmospheric dispersion/consequence models supporting safety analysis

    International Nuclear Information System (INIS)

    O'Kula, K.R.; Lazaro, M.A.; Woodard, K.

    1996-01-01

    Two DOE Working Groups have completed evaluation of accident phenomenology and consequence methodologies used to support DOE facility safety documentation. The independent evaluations each concluded that no one computer model adequately addresses all accident and atmospheric release conditions. MACCS2, MATHEW/ADPIC, TRAC RA/HA, and COSYMA are adequate for most radiological dispersion and consequence needs. ALOHA, DEGADIS, HGSYSTEM, TSCREEN, and SLAB are recommended for chemical dispersion and consequence applications. Additional work is suggested, principally in evaluation of new models, targeting certain models for continued development, training, and establishing a Web page for guidance to safety analysts

  3. Exploring Demographic Shifts : Aging and Migration Exploratory Group Model Specification & Simulation

    NARCIS (Netherlands)

    Pruyt, E.; Logtens, T.; Gijsbers, G.

    2011-01-01

    Plausible dynamics of a major demographic shift –(societal) aging– is studied in this paper, both from a global perspective and from a national perspective. Several economic, political and social implications of aging and aging-related demographic shifts are explored using System Dynamics models as

  4. Consequences of a demographic bottleneck on genetic structure and variation in the Scandinavian brown bear.

    Science.gov (United States)

    Xenikoudakis, G; Ersmark, E; Tison, J-L; Waits, L; Kindberg, J; Swenson, J E; Dalén, L

    2015-07-01

    The Scandinavian brown bear went through a major decline in population size approximately 100 years ago, due to intense hunting. After being protected, the population subsequently recovered and today numbers in the thousands. The genetic diversity in the contemporary population has been investigated in considerable detail, and it has been shown that the population consists of several subpopulations that display relatively high levels of genetic variation. However, previous studies have been unable to resolve the degree to which the demographic bottleneck impacted the contemporary genetic structure and diversity. In this study, we used mitochondrial and microsatellite DNA markers from pre- and postbottleneck Scandinavian brown bear samples to investigate the effect of the bottleneck. Simulation and multivariate analysis suggested the same genetic structure for the historical and modern samples, which are clustered into three subpopulations in southern, central and northern Scandinavia. However, the southern subpopulation appears to have gone through a marked change in allele frequencies. When comparing the mitochondrial DNA diversity in the whole population, we found a major decline in haplotype numbers across the bottleneck. However, the loss of autosomal genetic diversity was less pronounced, although a significant decline in allelic richness was observed in the southern subpopulation. Approximate Bayesian computations provided clear support for a decline in effective population size during the bottleneck, in both the southern and northern subpopulations. These results have implications for the future management of the Scandinavian brown bear because they indicate a recent loss in genetic diversity and also that the current genetic structure may have been caused by historical ecological processes rather than recent anthropogenic persecution. © 2015 John Wiley & Sons Ltd.

  5. WeedML: a Tool for Collaborative Weed Demographic Modeling

    OpenAIRE

    Holst, Niels

    2010-01-01

    WeedML is a proposed standard to formulate models of weed demography, or maybe even complex models in general, that are both transparent and straightforward to re-use as building blocks for new models. The paper describes the design and thoughts behind WeedML which relies on XML and object-oriented systems development. Proof-of-concept software is provided as open-source C++ code and executables that can be downloaded freely.

  6. A methodology for overall consequence modeling in chemical industry

    International Nuclear Information System (INIS)

    Arunraj, N.S.; Maiti, J.

    2009-01-01

    Risk assessment in chemical process industry is a very important issue for safeguarding human and the ecosystem from damages caused to them. Consequence assessment is an integral part of risk assessment. However, the commonly used consequence estimation methods involve time-consuming complex mathematical models and simple assimilation of losses without considering all the consequence factors. This lead to the deterioration of quality of estimated risk value. So, the consequence modeling has to be performed in detail considering all major losses with optimal time to improve the decisive value of risk. The losses can be broadly categorized into production loss, assets loss, human health and safety loss, and environment loss. In this paper, a conceptual framework is developed to assess the overall consequence considering all the important components of major losses. Secondly, a methodology is developed for the calculation of all the major losses, which are normalized to yield the overall consequence. Finally, as an illustration, the proposed methodology is applied to a case study plant involving benzene extraction. The case study result using the proposed consequence assessment scheme is compared with that from the existing methodologies.

  7. Low concentrations, potential ecological consequences: Synthetic estrogens alter life-history and demographic structures of aquatic invertebrates

    International Nuclear Information System (INIS)

    Souza, María Sol; Hallgren, Per; Balseiro, Esteban; Hansson, Lars-Anders

    2013-01-01

    Contraceptive drugs are nowadays found in aquatic environments around the globe. Particularly, 17α-ethinylestradiol (EE 2 ) may act even at low concentrations, such as those recorded in natural ecosystems. We evaluated the physiological effects of EE 2 on cyclopoids and calanoids, common copepods in both marine and freshwater communities. We used three EE 2 concentrations and assessed its impact on activity of different physiological endpoints: Acetylcholinesterase (neurotransmission), Glutathione S-transferase (detoxifying system), and Caspase-3 (apoptosis). While EE 2 exerts, distinctive effect on detoxifying and apoptotic systems, no effect on AChE was observed at environmental doses. Our results show that EE 2 exposure affects differently copepod physiology endpoints, altering moulting process, adult recruitment in calanoids and calanoid to cyclopoid ratio. The ecological consequences of this underlying physiological process may affect since life history to population and community structures, and this represent a new aspects of this xenobiotic in natural systems. Highlights: •We evaluated physiological effects of 17α-ethinylestradiol (EE 2 ) on copepods. •We measured the EE 2 effect on neurotransmission, detoxifying system and apoptosis. •EE 2 exert distinctive effect on detoxifying and apoptotic systems. •EE 2 affects differently calanoids and cyclopoids moulting and adult recruitment. •Physiological impact in invertebrates' communities is a novel aspect of EE 2 effects. -- Anthropogenic estrogens modify the physiological functioning of aquatic invertebrates

  8. Accessibility to Nodes of Interest: Demographic Weighting the Logistic Model

    Directory of Open Access Journals (Sweden)

    Gioacchino DE CANDIA

    2015-11-01

    Full Text Available This research fits into the genre of spatial analysis, aimed at better understanding of population dynamics in relation to the presence and distribution of infrastructure and related services. Specifically, the analysis uses a model of the gravitational type, based on the assumption of the impedance (attractiveness territorial, based on a curve of type logistics to determine the accessibility of the same, to which to add a system of weights. In this sense, the model was weighted according to the population, to determine the level of “population served” in terms of infrastructure and related services included in the model.

  9. Modeling Neolithic dispersal in Central Europe: demographic implications

    Czech Academy of Sciences Publication Activity Database

    Galeta, P.; Sládek, Vladimír; Sosna, D.; Brůžek, J.

    2011-01-01

    Roč. 146, č. 1 (2011), s. 104-115 ISSN 0002-9483 R&D Projects: GA ČR GA206/09/0589 Institutional research plan: CEZ:AV0Z60930519 Keywords : population projections * stochastic modeling * total fertility rate * growth rate Subject RIV: AC - Archeology, Anthropology, Ethnology Impact factor: 2.824, year: 2011

  10. Modelling of Consequences of Biogas Leakage from Gasholder

    Directory of Open Access Journals (Sweden)

    Petr Trávníček

    2017-03-01

    Full Text Available This paper describes modelling of consequences of biogas leakage from a gasholder on agricultural biogas station. Four scenarios were selected for the purpose of this work. A rupture of gasholders membrane and instantaneous explosion of gas cloud, blast of gas with delay, emptying of whole volume of gas (without initiation and initiation of gas with Jet-Fire. Leakage of gas is modelled by special software and consequences are determined on the basis of results. The first scenario was modelled with help of equations because used software does not include an appropriate model. A farm with high building density was chosen as a model case. Biogas is replaced by methane because used software does not support modelling of dispersion of mixtures. From this viewpoint, a conservative approach is applied because biogas contains “only” approximately 60% of methane (in dependence on technology and processed material.

  11. Modelling the evolution and consequences of mate choice

    OpenAIRE

    Tazzyman, S. J.

    2010-01-01

    This thesis considers the evolution and the consequences of mate choice across a variety of taxa, using game theoretic, population genetic, and quantitative genetic modelling techniques. Part I is about the evolution of mate choice. In chapter 2, a population genetic model shows that mate choice is even beneficial in self-fertilising species such as Saccharomyces yeast. In chapter 3, a game theoretic model shows that female choice will be strongly dependent upon whether the benefi...

  12. Modeling of budgetary funding influence on socio-demographic processes of a region

    Directory of Open Access Journals (Sweden)

    Aleksandra Vladimirovna Vasil'eva

    2012-06-01

    Full Text Available This paper describes a method of modeling socio-demographic processes in a region based on the minimax approach. In this method, the simulated socio-demographic processes reflect the performance of a population fertility age model, reproductive systems and the structure of mortality, as management impact tools of fiscal spending on socially significant budget items (health, physical culture and sport, social policy, education, environmental protection are considered. Testing methodology on the examples of the Russian Federation subjects included in the Ural Federal District is presented. Peculiarities of influence of funding of each socially important item on the social and demographic processes in the regions of the Ural Federal District are shown. Priorities of distribution of funds based on the level of budgetary provision in the region to ensure optimization of socio-demographic development of the region are shaped.

  13. Demographic consequences of increased winter births in a large aseasonally breeding mammal (Bos taurus) in response to climate change.

    Science.gov (United States)

    Burthe, Sarah; Butler, Adam; Searle, Kate R; Hall, Stephen J G; Thackeray, Stephen J; Wanless, Sarah

    2011-11-01

    1. Studies examining changes in the scheduling of breeding in response to climate change have focused on species with well-defined breeding seasons. Species exhibiting year-round breeding have received little attention and the magnitudes of any responses are unknown. 2. We investigated phenological data for an enclosed feral population of cattle (Bos taurus L.) in northern England exhibiting year-round breeding. This population is relatively free of human interference. 3. We assessed whether the timing of births had changed over the last 60 years, in response to increasing winter and spring temperatures, changes in herd density, and a regime of lime fertilisation. 4. Median birth date became earlier by 1·0 days per year. Analyses of the seasonal distribution of calving dates showed that significantly fewer calves were born in summer (decline from 44% of total births to 20%) and significantly more in winter (increase from 12% to 30%) over the study period. The most pronounced changes occurred in winter, with significant increases in both the proportion and number of births. Winter births arise from conceptions in the previous spring, and we considered models that investigated climate and weather variables associated with the winter preceding and the spring of conceptions. 5. The proportion of winter births was higher when the onset of the plant growing season was earlier during the spring of conceptions. This relationship was much weaker during years when the site had been fertilised with lime, suggesting that increased forage biomass was over-riding the impacts of changing plant phenology. When the onset of the growing season was late, winter births increased with female density. 6. Recruitment estimates from a stage-structured state-space population model were significantly negatively correlated with the proportion of births in the preceding winter, suggesting that calves born in winter are less likely to survive than those born in other seasons. 7.

  14. Consequence model of the German reactor safety study

    International Nuclear Information System (INIS)

    Bayer, A.; Aldrich, D.; Burkart, K.; Horsch, F.; Hubschmann, W.; Schueckler, M.; Vogt, S.

    1979-01-01

    The consequency model developed for phase A of the German Reactor Safety Study (RSS) is similar in many respects to its counterpart in WASH-1400. As in that previous study, the model describes the atmosphere dispersion and transport of radioactive material released from the containment during a postulated reactor accident, and predicts its interaction with and influence on man. Differences do exist between the two models however, for the following reasons: (1) to more adequately reflect central European conditions, (2) to include improved submodels, and (3) to apply additional data and knowledge that have become available since publication of WASH-1400. The consequence model as used in phase A of the German RSS is described, highlighting differences between it and the U.S. model

  15. Integrative demographic modeling reveals population level impacts of PCB toxicity to juvenile snapping turtles

    International Nuclear Information System (INIS)

    Salice, Christopher J.; Rowe, Christopher L.; Eisenreich, Karen M.

    2014-01-01

    A significant challenge in ecotoxicology and risk assessment lies in placing observed contaminant effects in a meaningful ecological context. Polychlorinated biphenyls (PCBs) have been shown to affect juvenile snapping turtle survival and growth but the ecological significance of these effects is difficult to discern without a formal, population-level assessment. We used a demographic matrix model to explore the potential population-level effects of PCBs on turtles. Our model showed that effects of PCBs on juvenile survival, growth and size at hatching could translate to negative effects at the population level despite the fact that these life cycle components do not typically contribute strongly to population level processes. This research points to the utility of using integrative demographic modeling approaches to better understand contaminant effects in wildlife. The results indicate that population-level effects are only evident after several years, suggesting that for long-lived species, detecting adverse contaminant effects could prove challenging. -- Highlights: • Previous studies have shown the PCBs can impact juvenile snapping turtles. • We used a demographic model of turtles to evaluate population-level PCB effects. • PCB effects on turtles may translate to negative population responses. • Long-term monitoring is needed to detect contaminant effects on natural turtle populations. • Demographic models can improve our understanding contaminant ecotoxicity. -- A demographic model was used to show that PCB induced effects on young snapping turtles can result in adverse effects at the population level

  16. Developments in consequence modelling of accidental releases of hazardous materials

    NARCIS (Netherlands)

    Boot, H.

    2012-01-01

    The modelling of consequences of releases of hazardous materials in the Netherlands has mainly been based on the “Yellow Book”. Although there is no updated version of this official publication, new insights have been developed during the last decades. This article will give an overview of new

  17. Accident consequence assessments with different atmospheric dispersion models

    International Nuclear Information System (INIS)

    Panitz, H.J.

    1989-11-01

    An essential aim of the improvements of the new program system UFOMOD for Accident Consequence Assessments (ACAs) was to substitute the straight-line Gaussian plume model conventionally used in ACA models by more realistic atmospheric dispersion models. To identify improved models which can be applied in ACA codes and to quantify the implications of different dispersion models on the results of an ACA, probabilistic comparative calculations with different atmospheric dispersion models have been performed. The study showed that there are trajectory models available which can be applied in ACAs and that they provide more realistic results of ACAs than straight-line Gaussian models. This led to a completely novel concept of atmospheric dispersion modelling in which two different distance ranges of validity are distinguished: the near range of some ten kilometres distance and the adjacent far range which are assigned to respective trajectory models. (orig.) [de

  18. Particle size - An important factor in environmental consequence modeling

    International Nuclear Information System (INIS)

    Yuan, Y.C.; MacFarlane, D.

    1991-01-01

    Most available environmental transport and dosimetry codes for radiological consequence analysis are designed primarily for estimating dose and health consequences to specific off-site individuals as well as the population as a whole from nuclear facilities operating under either normal or accident conditions. Models developed for these types of analyses are generally based on assumptions that the receptors are at great distances (several kilometers), and the releases are prolonged and filtered. This allows the use of simplified approaches such as averaged meteorological conditions and the use of a single (small) particle size for atmospheric transport and dosimetry analysis. Source depletion from particle settling, settle-out, and deposition is often ignored. This paper estimates the effects of large particles on the resulting dose consequences from an atmospheric release. The computer program AI-RISK has been developed to perform multiparticle-sized atmospheric transport, dose, and pathway analyses for estimating potential human health consequences from the accidental release of radioactive materials. The program was originally developed to facilitate comprehensive analyses of health consequences, ground contamination, and cleanup associated with possible energetic chemical reactions in high-level radioactive waste (HLW) tanks at a US Department of Energy site

  19. [The theory of the demographic transition as a reference for demo-economic models].

    Science.gov (United States)

    Genne, M

    1981-01-01

    The aim of the theory of demographic transition (TTD) is to better understand the behavior and interrelationship of economic and demographic variables. There are 2 types of demo-economic models: 1) the malthusian models, which consider demographic variables as pure exogenous variables, and 2) the neoclassical models, which consider demographic variables as strictly endogenous. If TTD can explore the behavior of exogenous and endogenous demographic variables, it cannot demonstrate neither the relation nor the order of causality among the various demographic and economic variables, but it is simply the theoretical framework of a complex social and economic phenomenon which started in Europe in the 19th Century, and which today can be extended to developing countries. There are 4 stages in the TTD; the 1st stage is characterized by high levels of fecundity and mortality; the 2nd stage is characterized by high fecundity levels and declining mortality levels; the 3rd stage is characterized by declining fecundity levels and low mortality levels; the 4th stage is characterized by low fertility and mortality levels. The impact of economic variables over mortality and birth rates is evident for mortality rates, which decline earlier and at a greater speed than birth rates. According to reliable mathematical predictions, around the year 1987 mortality rates in developing countries will have reached the low level of European countries, and growth rate will be only 1.5%. If the validity of demo-economic models has not yet been established, TTD has clearly shown that social and economic development is the factor which influences demographic expansion.

  20. Health effects models for nuclear power plant accident consequence analysis

    International Nuclear Information System (INIS)

    Abrahamson, S.; Bender, M.A.; Boecker, B.B.; Scott, B.R.

    1993-05-01

    The Nuclear Regulatory Commission (NRC) has sponsored several studies to identify and quantify, through the use of models, the potential health effects of accidental releases of radionuclides from nuclear power plants. The Reactor Safety Study provided the basis for most of the earlier estimates related to these health effects. Subsequent efforts by NRC-supported groups resulted in improved health effects models that were published in the report entitled open-quotes Health Effects Models for Nuclear Power Plant Consequence Analysisclose quotes, NUREG/CR-4214, 1985 and revised further in the 1989 report NUREG/CR-4214, Rev. 1, Part 2. The health effects models presented in the 1989 NUREG/CR-4214 report were developed for exposure to low-linear energy transfer (LET) (beta and gamma) radiation based on the best scientific information available at that time. Since the 1989 report was published, two addenda to that report have been prepared to (1) incorporate other scientific information related to low-LET health effects models and (2) extend the models to consider the possible health consequences of the addition of alpha-emitting radionuclides to the exposure source term. The first addendum report, entitled open-quotes Health Effects Models for Nuclear Power Plant Accident Consequence Analysis, Modifications of Models Resulting from Recent Reports on Health Effects of Ionizing Radiation, Low LET Radiation, Part 2: Scientific Bases for Health Effects Models,close quotes was published in 1991 as NUREG/CR-4214, Rev. 1, Part 2, Addendum 1. This second addendum addresses the possibility that some fraction of the accident source term from an operating nuclear power plant comprises alpha-emitting radionuclides. Consideration of chronic high-LET exposure from alpha radiation as well as acute and chronic exposure to low-LET beta and gamma radiations is a reasonable extension of the health effects model

  1. Domestic policy consequences of new implementation models. Consequences for industrial niches; Industripolitiske konsekvenser av nye gjennomfoeringsmodeller. Konsekvenser for nisjebedriftene

    Energy Technology Data Exchange (ETDEWEB)

    Johannessen, T.

    1995-12-31

    The paper relates to the consequences of domestic policy with the focus on new implementation models used for cost reduction of offshore development projects in Norway. The paper puts the attention to the consequences from implementation models on industrial niches (subcontractors)

  2. Consequences of models for monojet events from Z boson decay

    International Nuclear Information System (INIS)

    Baer, H.; Komamiya, S.; Hagiwara, K.

    1985-02-01

    Three models for monojet events with large missing transverse momentum observed at the CERN panti p collider are studied: i) Z decay into a neutral lepton pair where one of the pair decays within the detecter while the other escapes, ii) Z decay into two distinct neutral scalars where the lighter one is long lived, and iii) Z decay into two distinct higgsinos where the lighter one is long lived. The first model necessarily gives observable decay in flight signals. Consequences of the latter two models are investigated in both panti p collisions at CERN and e + e - annihilation at PETRA/PEP energies. (orig.)

  3. The concept of validation of numerical models for consequence analysis

    International Nuclear Information System (INIS)

    Borg, Audun; Paulsen Husted, Bjarne; Njå, Ove

    2014-01-01

    Numerical models such as computational fluid dynamics (CFD) models are increasingly used in life safety studies and other types of analyses to calculate the effects of fire and explosions. The validity of these models is usually established by benchmark testing. This is done to quantitatively measure the agreement between the predictions provided by the model and the real world represented by observations in experiments. This approach assumes that all variables in the real world relevant for the specific study are adequately measured in the experiments and in the predictions made by the model. In this paper the various definitions of validation for CFD models used for hazard prediction are investigated to assess their implication for consequence analysis in a design phase. In other words, how is uncertainty in the prediction of future events reflected in the validation process? The sources of uncertainty are viewed from the perspective of the safety engineer. An example of the use of a CFD model is included to illustrate the assumptions the analyst must make and how these affect the prediction made by the model. The assessments presented in this paper are based on a review of standards and best practice guides for CFD modeling and the documentation from two existing CFD programs. Our main thrust has been to assess how validation work is performed and communicated in practice. We conclude that the concept of validation adopted for numerical models is adequate in terms of model performance. However, it does not address the main sources of uncertainty from the perspective of the safety engineer. Uncertainty in the input quantities describing future events, which are determined by the model user, outweighs the inaccuracies in the model as reported in validation studies. - Highlights: • Examine the basic concept of validation applied to models for consequence analysis. • Review standards and guides for validation of numerical models. • Comparison of the validation

  4. Overview of the reactor safety study consequence model

    International Nuclear Information System (INIS)

    Wall, I.B.; Yaniv, S.S.; Blond, R.M.; McGrath, P.E.; Church, H.W.; Wayland, J.R.

    1977-01-01

    The Reactor Safety Study (WASH-1400) is a comprehensive assessment of the potential risk to the public from accidents in light water power reactors. The engineering analysis of the plants is described in detail in the Reactor Safety Study: it provides an estimate of the probability versus magnitude of the release of radioactive material. The consequence model, which is the subject of this paper, describes the progression of the postulated accident after the release of the radioactive material from the containment. A brief discussion of the manner in which the consequence calculations are performed is presented. The emphasis in the description is on the models and data that differ significantly from those previously used for these types of assessments. The results of the risk calculations for 100 light water power reactors are summarized

  5. Modeling Relationships Between Flight Crew Demographics and Perceptions of Interval Management

    Science.gov (United States)

    Remy, Benjamin; Wilson, Sara R.

    2016-01-01

    The Interval Management Alternative Clearances (IMAC) human-in-the-loop simulation experiment was conducted to assess interval management system performance and participants' acceptability and workload while performing three interval management clearance types. Twenty-four subject pilots and eight subject controllers flew ten high-density arrival scenarios into Denver International Airport during two weeks of data collection. This analysis examined the possible relationships between subject pilot demographics on reported perceptions of interval management in IMAC. Multiple linear regression models were created with a new software tool to predict subject pilot questionnaire item responses from demographic information. General patterns were noted across models that may indicate flight crew demographics influence perceptions of interval management.

  6. The accident consequence model of the German safety study

    International Nuclear Information System (INIS)

    Huebschmann, W.

    1977-01-01

    The accident consequence model essentially describes a) the diffusion in the atmosphere and deposition on the soil of radioactive material released from the reactor into the atmosphere; b) the irradiation exposure and health consequences of persons affected. It is used to calculate c) the number of persons suffering from acute or late damage, taking into account possible counteractions such as relocation or evacuation, and d) the total risk to the population from the various types of accident. The model, the underlying parameters and assumptions are described. The bone marrow dose distribution is shown for the case of late overpressure containment failure, which is discussed in the paper of Heuser/Kotthoff, combined with four typical weather conditions. The probability distribution functions for acute mortality, late incidence of cancer and genetic damage are evaluated, assuming a characteristic population distribution. The aim of these calculations is first the presentation of some results of the consequence model as an example, in second the identification of problems, which need possibly in a second phase of study to be evaluated in more detail. (orig.) [de

  7. Consequence and Resilience Modeling for Chemical Supply Chains

    Science.gov (United States)

    Stamber, Kevin L.; Vugrin, Eric D.; Ehlen, Mark A.; Sun, Amy C.; Warren, Drake E.; Welk, Margaret E.

    2011-01-01

    The U.S. chemical sector produces more than 70,000 chemicals that are essential material inputs to critical infrastructure systems, such as the energy, public health, and food and agriculture sectors. Disruptions to the chemical sector can potentially cascade to other dependent sectors, resulting in serious national consequences. To address this concern, the U.S. Department of Homeland Security (DHS) tasked Sandia National Laboratories to develop a predictive consequence modeling and simulation capability for global chemical supply chains. This paper describes that capability , which includes a dynamic supply chain simulation platform called N_ABLE(tm). The paper also presents results from a case study that simulates the consequences of a Gulf Coast hurricane on selected segments of the U.S. chemical sector. The case study identified consequences that include impacted chemical facilities, cascading impacts to other parts of the chemical sector. and estimates of the lengths of chemical shortages and recovery . Overall. these simulation results can DHS prepare for and respond to actual disruptions.

  8. Socio-demographic characteristics affecting sport tourism choices: A structural model

    Directory of Open Access Journals (Sweden)

    Nataša Slak Valek

    2014-03-01

    Full Text Available Background: Effective tourism management in the field of sports tourism requires an understanding of differences in socioeconomic characteristics both within and between different market segments. Objective: In the broad tourism market demographic characteristics have been extensively analyzed for differences in destination choices, however little is known about demographic factors affecting sport tourists' decisions. Methods: A sample of Slovenian sports tourists was analyzed using data from a comprehensive survey of local and outbound tourist activity conducted by the Statistical Office of the Republic of Slovenia in 2008. After data weighting the information for 353,783 sports related trips were available for analysis. The research model adopted suggests that four socio-demographic characteristics (gender, age, level of education and income significantly affect a tourist's choice of sports related travel either locally within Slovenia or to a foreign country. Furthermore the destination (local or foreign has an influence on the choice of the type of accommodation selected and the tourist's total expenditure for the trip. For testing the first part of our model (the socio-demographic characteristics effects a linear regression was used, and for the final part of the model (the selection of accommodation type and travel expenditure t-test were applied. Results: The result shows the standardized β regression coefficients are all statistically significant at the .001 level for the tested socio-demographic characteristics and also the overall regression model was statistically significant at .001 level. Conclusions: With these results the study confirmed that all the selected socio-demographic characteristics have a significant influence on the sport-active tourist when choosing between a domestic and foreign tourism destination which in turn affect the type of accommodation chosen and the level of expenditure while travelling.

  9. A demographic model to predict future growth of the Addo elephant population

    OpenAIRE

    A.M. Woodd

    1999-01-01

    An age-structured demographic model of the growth of the Addo elephant population was developed using parameters calculated from long-term data on the population. The model was used to provide estimates of future population growth. Expansion of the Addo Elephant National Park is currently underway, and the proposed target population size for elephant within the enlarged park is 2700. The model predicts that this population size will be reached during the year 2043, so that the Addo elephant p...

  10. Spatial demographic models to inform conservation planning of golden eagles in renewable energy landscapes.

    Science.gov (United States)

    Spatial demographic models can help guide monitoring and management activities targeting at-risk species, even in cases where baseline data are lacking. Here, we provide an example of how site-specific changes in land-use and other anthropogenic stressors can be incorporated int...

  11. Demographic Accounting and Model-Building. Education and Development Technical Reports.

    Science.gov (United States)

    Stone, Richard

    This report describes and develops a model for coordinating a variety of demographic and social statistics within a single framework. The framework proposed, together with its associated methods of analysis, serves both general and specific functions. The general aim of these functions is to give numerical definition to the pattern of society and…

  12. Modeling of criticality accidents and their environmental consequences

    International Nuclear Information System (INIS)

    Thomas, W.; Gmal, B.

    1987-01-01

    In the Federal Republic of Germany, potential radiological consequences of accidental nuclear criticality have to be evaluated in the licensing procedure for fuel cycle facilities. A prerequisite to this evaluation is to establish conceivable accident scenarios. First, possibilities for a criticality exceeding the generally applied double contingency principle of safety are identified by screening the equipment and operation of the facility. Identification of undetected accumulations of fissile material or incorrect transfer of fissile solution to unfavorable geometry normally are most important. Second, relevant and credible scenarios causing the most severe consequences are derived from these possibilities. For the identified relevant scenarios, time-dependent fission rates and reasonable numbers for peak power and total fissions must be determined. Experience from real accidents and experiments (KEWB, SPERT, CRAC, SILENE) has been evaluated using empirical formulas. To model the time-dependent behavior of criticality excursions in fissile solutions, a computer program FELIX has been developed

  13. Hierarchial mark-recapture models: a framework for inference about demographic processes

    Science.gov (United States)

    Link, W.A.; Barker, R.J.

    2004-01-01

    The development of sophisticated mark-recapture models over the last four decades has provided fundamental tools for the study of wildlife populations, allowing reliable inference about population sizes and demographic rates based on clearly formulated models for the sampling processes. Mark-recapture models are now routinely described by large numbers of parameters. These large models provide the next challenge to wildlife modelers: the extraction of signal from noise in large collections of parameters. Pattern among parameters can be described by strong, deterministic relations (as in ultrastructural models) but is more flexibly and credibly modeled using weaker, stochastic relations. Trend in survival rates is not likely to be manifest by a sequence of values falling precisely on a given parametric curve; rather, if we could somehow know the true values, we might anticipate a regression relation between parameters and explanatory variables, in which true value equals signal plus noise. Hierarchical models provide a useful framework for inference about collections of related parameters. Instead of regarding parameters as fixed but unknown quantities, we regard them as realizations of stochastic processes governed by hyperparameters. Inference about demographic processes is based on investigation of these hyperparameters. We advocate the Bayesian paradigm as a natural, mathematically and scientifically sound basis for inference about hierarchical models. We describe analysis of capture-recapture data from an open population based on hierarchical extensions of the Cormack-Jolly-Seber model. In addition to recaptures of marked animals, we model first captures of animals and losses on capture, and are thus able to estimate survival probabilities w (i.e., the complement of death or permanent emigration) and per capita growth rates f (i.e., the sum of recruitment and immigration rates). Covariation in these rates, a feature of demographic interest, is explicitly

  14. High feather mercury concentrations in the wandering albatross are related to sex, breeding status and trophic ecology with no demographic consequences

    Energy Technology Data Exchange (ETDEWEB)

    Bustamante, Paco, E-mail: pbustama@univ-lr.fr [Littoral Environnement et Sociétés (LIENSs), UMR 7266 CNRS-Université de la Rochelle, 2 rue Olympe de Gouges, 17000 La Rochelle (France); Carravieri, Alice [Littoral Environnement et Sociétés (LIENSs), UMR 7266 CNRS-Université de la Rochelle, 2 rue Olympe de Gouges, 17000 La Rochelle (France); Centre d’Etudes Biologiques de Chizé (CEBC), UMR 7372 du Centre National de la Recherche Scientifique-Université de La Rochelle, 79360 Villiers-en-Bois (France); Goutte, Aurélie [Centre d’Etudes Biologiques de Chizé (CEBC), UMR 7372 du Centre National de la Recherche Scientifique-Université de La Rochelle, 79360 Villiers-en-Bois (France); École Pratique des Hautes Études (EPHE), SPL, UPMC Université Paris 06, UMR 7619 METIS, F-75005, 4 place Jussieu, Paris (France); Barbraud, Christophe; Delord, Karine; Chastel, Olivier; Weimerskirch, Henri; Cherel, Yves [Centre d’Etudes Biologiques de Chizé (CEBC), UMR 7372 du Centre National de la Recherche Scientifique-Université de La Rochelle, 79360 Villiers-en-Bois (France)

    2016-01-15

    Hg can affect physiology of seabirds and ultimately their demography, particularly if they are top consumers. In the present study, body feathers of >200 wandering albatrosses from Possession Island in the Crozet archipelago were used to explore the potential demographic effects of the long-term exposure to Hg on an apex predator. Variations of Hg with sex, age class, foraging habitat (inferred from δ{sup 13}C values), and feeding habits (inferred from δ{sup 15}N values) were examined as well as the influence of Hg on current breeding output, long-term fecundity and survival. Wandering albatrosses displayed among the highest Hg feather concentrations reported for seabirds, ranging from 5.9 to 95 µg g{sup −1}, as a consequence of their high trophic position (δ{sup 15}N values). These concentrations fall within the same range of those of other wandering albatross populations from subantarctic sites, suggesting that this species has similar exposure to Hg all around the Southern Ocean. In both immature and adult albatrosses, females had higher Hg concentrations than males (28 vs. 20 µg g{sup −1} dw on average, respectively), probably as a consequence of females foraging at lower latitudes than males (δ{sup 13}C values). Hg concentrations were higher in immature than in adult birds, and they remained fairly constant across a wide range of ages in adults. Such high levels in immature individuals question (i) the frequency of moult in young birds, (ii) the efficiency of Hg detoxification processes in immatures compared to adults, and (iii) importantly the potential detrimental effects of Hg in early life. Despite very high Hg concentrations in their feathers, neither effects on adults' breeding probability, hatching failure and fledgling failure, nor on adults' survival rate were detected, suggesting that long-term bioaccumulated Hg was not under a chemical form leading to deleterious effects on reproductive parameters in adult individuals

  15. High feather mercury concentrations in the wandering albatross are related to sex, breeding status and trophic ecology with no demographic consequences

    International Nuclear Information System (INIS)

    Bustamante, Paco; Carravieri, Alice; Goutte, Aurélie; Barbraud, Christophe; Delord, Karine; Chastel, Olivier; Weimerskirch, Henri; Cherel, Yves

    2016-01-01

    Hg can affect physiology of seabirds and ultimately their demography, particularly if they are top consumers. In the present study, body feathers of >200 wandering albatrosses from Possession Island in the Crozet archipelago were used to explore the potential demographic effects of the long-term exposure to Hg on an apex predator. Variations of Hg with sex, age class, foraging habitat (inferred from δ 13 C values), and feeding habits (inferred from δ 15 N values) were examined as well as the influence of Hg on current breeding output, long-term fecundity and survival. Wandering albatrosses displayed among the highest Hg feather concentrations reported for seabirds, ranging from 5.9 to 95 µg g −1 , as a consequence of their high trophic position (δ 15 N values). These concentrations fall within the same range of those of other wandering albatross populations from subantarctic sites, suggesting that this species has similar exposure to Hg all around the Southern Ocean. In both immature and adult albatrosses, females had higher Hg concentrations than males (28 vs. 20 µg g −1 dw on average, respectively), probably as a consequence of females foraging at lower latitudes than males (δ 13 C values). Hg concentrations were higher in immature than in adult birds, and they remained fairly constant across a wide range of ages in adults. Such high levels in immature individuals question (i) the frequency of moult in young birds, (ii) the efficiency of Hg detoxification processes in immatures compared to adults, and (iii) importantly the potential detrimental effects of Hg in early life. Despite very high Hg concentrations in their feathers, neither effects on adults' breeding probability, hatching failure and fledgling failure, nor on adults' survival rate were detected, suggesting that long-term bioaccumulated Hg was not under a chemical form leading to deleterious effects on reproductive parameters in adult individuals. - Highlights: • Immature

  16. Ensemble atmospheric dispersion modeling for emergency response consequence assessments

    International Nuclear Information System (INIS)

    Addis, R.P.; Buckley, R.L.

    2003-01-01

    Full text: Prognostic atmospheric dispersion models are used to generate consequence assessments, which assist decision-makers in the event of a release from a nuclear facility. Differences in the forecast wind fields generated by various meteorological agencies, differences in the transport and diffusion models themselves, as well as differences in the way these models treat the release source term, all may result in differences in the simulated plumes. This talk will address the U.S. participation in the European ENSEMBLE project, and present a perspective an how ensemble techniques may be used to enable atmospheric modelers to provide decision-makers with a more realistic understanding of how both the atmosphere and the models behave. Meteorological forecasts generated by numerical models from national and multinational meteorological agencies provide individual realizations of three-dimensional, time dependent atmospheric wind fields. These wind fields may be used to drive atmospheric dispersion (transport and diffusion) models, or they may be used to initiate other, finer resolution meteorological models, which in turn drive dispersion models. Many modeling agencies now utilize ensemble-modeling techniques to determine how sensitive the prognostic fields are to minor perturbations in the model parameters. However, the European Union programs RTMOD and ENSEMBLE are the first projects to utilize a WEB based ensemble approach to interpret the output from atmospheric dispersion models. The ensembles produced are different from those generated by meteorological forecasting centers in that they are ensembles of dispersion model outputs from many different atmospheric transport and diffusion models utilizing prognostic atmospheric fields from several different forecast centers. As such, they enable a decision-maker to consider the uncertainty in the plume transport and growth as a result of the differences in the forecast wind fields as well as the differences in the

  17. Conservation biology for suites of species: Demographic modeling for Pacific island kingfishers

    Science.gov (United States)

    Kesler, D.C.; Haig, S.M.

    2007-01-01

    Conservation practitioners frequently extrapolate data from single-species investigations when managing critically endangered populations. However, few researchers initiate work with the intent of making findings useful to conservation efforts for other species. We presented and explored the concept of conducting conservation-oriented research for suites of geographically separated populations with similar natural histories, resource needs, and extinction threats. An example was provided in the form of an investigation into the population demography of endangered Micronesian kingfishers (Todiramphus cinnamominus). We provided the first demographic parameter estimates for any of the 12 endangered Pacific Todiramphus species, and used results to develop a population projection matrix model for management throughout the insular Pacific. Further, we used the model for elasticity and simulation analyses with demographic values that randomly varied across ranges that might characterize congener populations. Results from elasticity and simulation analyses indicated that changes in breeding adult survival exerted the greatest magnitude of influence on population dynamics. However, changes in nestling survival were more consistently correlated with population dynamics as demographic rates were randomly altered. We concluded that conservation practitioners working with endangered Pacific kingfishers should primarily focus efforts on factors affecting nestling and breeder survival, and secondarily address fledgling juveniles and helpers. Further, we described how the generalized base model might be changed to focus on individual populations and discussed the potential application of multi-species models to other conservation situations. ?? 2007 Elsevier Ltd. All rights reserved.

  18. Health effects models for nuclear power plant accident consequence analysis

    International Nuclear Information System (INIS)

    Evans, J.S.; Abrahmson, S.; Bender, M.A.; Boecker, B.B.; Scott, B.R.; Gilbert, E.S.

    1993-10-01

    This report is a revision of NUREG/CR-4214, Rev. 1, Part 1 (1990), Health Effects Models for Nuclear Power Plant Accident Consequence Analysis. This revision has been made to incorporate changes to the Health Effects Models recommended in two addenda to the NUREG/CR-4214, Rev. 1, Part 11, 1989 report. The first of these addenda provided recommended changes to the health effects models for low-LET radiations based on recent reports from UNSCEAR, ICRP and NAS/NRC (BEIR V). The second addendum presented changes needed to incorporate alpha-emitting radionuclides into the accident exposure source term. As in the earlier version of this report, models are provided for early and continuing effects, cancers and thyroid nodules, and genetic effects. Weibull dose-response functions are recommended for evaluating the risks of early and continuing health effects. Three potentially lethal early effects -- the hematopoietic, pulmonary, and gastrointestinal syndromes are considered. Linear and linear-quadratic models are recommended for estimating the risks of seven types of cancer in adults - leukemia, bone, lung, breast, gastrointestinal, thyroid, and ''other''. For most cancers, both incidence and mortality are addressed. Five classes of genetic diseases -- dominant, x-linked, aneuploidy, unbalanced translocations, and multifactorial diseases are also considered. Data are provided that should enable analysts to consider the timing and severity of each type of health risk

  19. Testing of an accident consequence assessment model using field data

    International Nuclear Information System (INIS)

    Homma, Toshimitsu; Matsubara, Takeshi; Tomita, Kenichi

    2007-01-01

    This paper presents the results obtained from the application of an accident consequence assessment model, OSCAAR to the Iput dose reconstruction scenario of BIOMASS and also to the Chernobyl 131 I fallout scenario of EMRAS, both organized by International Atomic Energy Agency. The Iput Scenario deals with 137 Cs contamination of the catchment basin and agricultural area in the Bryansk Region of Russia, which was heavily contaminated after the Chernobyl accident. This exercise was used to test the chronic exposure pathway models in OSCAAR with actual measurements and to identify the most important sources of uncertainty with respect to each part of the assessment. The OSCAAR chronic exposure pathway models had some limitations but the refined model, COLINA almost successfully reconstructed the whole 10-year time course of 137 Cs activity concentrations in most requested types of agricultural products and natural foodstuffs. The Plavsk scenario provides a good opportunity to test not only the food chain transfer model of 131 I but also the method of assessing 131 I thyroid burden. OSCAAR showed in general good capabilities for assessing the important 131 I exposure pathways. (author)

  20. Igneous Consequence Modeling for the TSPA-SR

    International Nuclear Information System (INIS)

    McCord, John

    2001-01-01

    The purpose of this technical report is to develop credible, defendable, substantiated models for the consequences of igneous activity for the TSPA-SR Model. The effort will build on the TSPA-VA and improve the quality of scenarios and depth of the technical basis underlying disruptive events modeling. Computational models for both volcanic eruptive releases (this is an event that results in ash containing waste being ejected from Yucca Mountain) and igneous intrusion groundwater releases (this is an event that reaches the repository level, impacts the waste packages, and produces releases from waste packages damaged by igneous activity) will be included directly in the TSPA calculations as part of the TSPA-SR Model. This Analysis Model Report (AMR) is limited to development of the conceptual models for these two scenarios. The mathematical implementation of these conceptual models will be done within the TSPA-SR Model. Thus, this AMR will not include any model results or sensitivity analyses. Calculation of any doses resulting from igneous releases will also be done within the TSPA-SR model, as will the probabilistic weighting of these doses. Calculation and analysis of the TSPA-SR Model results for igneous disruption are, therefore, outside the scope of this activity. The reason for not running the mathematical models as part of this AMR is that the models are integrated within the TSPA-SR model and, thus, any model simulations and the corresponding results are out of the scope of this AMR. The scope of this work as defined in the development plan (CRWMS M and O 2000j) involves using data that has been extracted from existing sources to design and support the TSPA-SR models for the transport of radionuclides following igneous disruption of the repository. The development plan states ''applications of the code in this analysis will be limited to testing of the code and sensitivity analyses during analysis design.'' In contrast to the development plan, the ASHPLUME

  1. A demographic model to predict future growth of the Addo elephant population

    Directory of Open Access Journals (Sweden)

    A.M. Woodd

    1999-07-01

    Full Text Available An age-structured demographic model of the growth of the Addo elephant population was developed using parameters calculated from long-term data on the population. The model was used to provide estimates of future population growth. Expansion of the Addo Elephant National Park is currently underway, and the proposed target population size for elephant within the enlarged park is 2700. The model predicts that this population size will be reached during the year 2043, so that the Addo elephant population can continue to increase for a further 44 years before its target size within the enlarged park is attained.

  2. Mapping populations at risk: improving spatial demographic data for infectious disease modeling and metric derivation

    Directory of Open Access Journals (Sweden)

    Tatem Andrew J

    2012-05-01

    Full Text Available Abstract The use of Global Positioning Systems (GPS and Geographical Information Systems (GIS in disease surveys and reporting is becoming increasingly routine, enabling a better understanding of spatial epidemiology and the improvement of surveillance and control strategies. In turn, the greater availability of spatially referenced epidemiological data is driving the rapid expansion of disease mapping and spatial modeling methods, which are becoming increasingly detailed and sophisticated, with rigorous handling of uncertainties. This expansion has, however, not been matched by advancements in the development of spatial datasets of human population distribution that accompany disease maps or spatial models. Where risks are heterogeneous across population groups or space or dependent on transmission between individuals, spatial data on human population distributions and demographic structures are required to estimate infectious disease risks, burdens, and dynamics. The disease impact in terms of morbidity, mortality, and speed of spread varies substantially with demographic profiles, so that identifying the most exposed or affected populations becomes a key aspect of planning and targeting interventions. Subnational breakdowns of population counts by age and sex are routinely collected during national censuses and maintained in finer detail within microcensus data. Moreover, demographic and health surveys continue to collect representative and contemporary samples from clusters of communities in low-income countries where census data may be less detailed and not collected regularly. Together, these freely available datasets form a rich resource for quantifying and understanding the spatial variations in the sizes and distributions of those most at risk of disease in low income regions, yet at present, they remain unconnected data scattered across national statistical offices and websites. In this paper we discuss the deficiencies of existing

  3. Estimating demographic parameters using a combination of known-fate and open N-mixture models.

    Science.gov (United States)

    Schmidt, Joshua H; Johnson, Devin S; Lindberg, Mark S; Adams, Layne G

    2015-10-01

    Accurate estimates of demographic parameters are required to infer appropriate ecological relationships and inform management actions. Known-fate data from marked individuals are commonly used to estimate survival rates, whereas N-mixture models use count data from unmarked individuals to estimate multiple demographic parameters. However, a joint approach combining the strengths of both analytical tools has not been developed. Here we develop an integrated model combining known-fate and open N-mixture models, allowing the estimation of detection probability, recruitment, and the joint estimation of survival. We demonstrate our approach through both simulations and an applied example using four years of known-fate and pack count data for wolves (Canis lupus). Simulation results indicated that the integrated model reliably recovered parameters with no evidence of bias, and survival estimates were more precise under the joint model. Results from the applied example indicated that the marked sample of wolves was biased toward individuals with higher apparent survival rates than the unmarked pack mates, suggesting that joint estimates may be more representative of the overall population. Our integrated model is a practical approach for reducing bias while increasing precision and the amount of information gained from mark-resight data sets. We provide implementations in both the BUGS language and an R package.

  4. Using a generalised identity reference model with archetypes to support interoperability of demographics information in electronic health record systems.

    Science.gov (United States)

    Xu Chen; Berry, Damon; Stephens, Gaye

    2015-01-01

    Computerised identity management is in general encountered as a low-level mechanism that enables users in a particular system or region to securely access resources. In the Electronic Health Record (EHR), the identifying information of both the healthcare professionals who access the EHR and the patients whose EHR is accessed, are subject to change. Demographics services have been developed to manage federated patient and healthcare professional identities and to support challenging healthcare-specific use cases in the presence of diverse and sometimes conflicting demographic identities. Demographics services are not the only use for identities in healthcare. Nevertheless, contemporary EHR specifications limit the types of entities that can be the actor or subject of a record to health professionals and patients, thus limiting the use of two level models in other healthcare information systems. Demographics are ubiquitous in healthcare, so for a general identity model to be usable, it should be capable of managing demographic information. In this paper, we introduce a generalised identity reference model (GIRM) based on key characteristics of five surveyed demographic models. We evaluate the GIRM by using it to express the EN13606 demographics model in an extensible way at the metadata level and show how two-level modelling can support the exchange of instances of demographic identities. This use of the GIRM to express demographics information shows its application for standards-compliant two-level modelling alongside heterogeneous demographics models. We advocate this approach to facilitate the interoperability of identities between two-level model-based EHR systems and show the validity and the extensibility of using GIRM for the expression of other health-related identities.

  5. Vertebrates population response to the climatic change - pertinence of the environmental indicators and influence of the demographic strategies and consequences for the biodiversity dynamic

    International Nuclear Information System (INIS)

    Weimerskirch, H.

    2007-01-01

    There is a growing interest and major challenge to understand the way environmental variability and climatic change have affected and will affect ecosystems and populations. Long-term records of population parameters of vertebrates are rare, but invaluable to address this challenge. The network CLIMPOP brings together French researchers working with long term data collected on individually marked animals to study the effects of climate change on a range of vertebrate populations (reptiles, birds and mammals) and standardised methods to link climatic factors and demographic parameters. The funding from GICC-IFB has allowed the CLIMPOP group to hire a post doc bridging methodologists and ecologists, organize a workshop and support field studies. Several analyses on a series of vertebrates have been carried out on the link between large-scale and small-scale climatic factors and population dynamics. In addition the CLIMPOP group has carried out a major methodological paper reviewing statistical models and procedures to study the influence of climate on vital rates based on the analysis of individual monitoring data, to identify potential pitfalls in the utilization of these models and procedures, to review published papers in which the influence of climatic variation on survival probability in vertebrate populations has been addressed, to evaluate whether the results from these studies are relevant and to draw practical recommendations to efficiently address effects of climate effects on vital rates in natural vertebrate populations. This evaluation raised six potential methodological issues and indicates that so far most of the studies found in the ecological literature can be considered as being useful for the purpose of generating hypothesis rather than for that of obtaining solid evidence for the impact of climatic factors on vital rates. (author)

  6. DESCARTES' RULE OF SIGNS AND THE IDENTIFIABILITY OF POPULATION DEMOGRAPHIC MODELS FROM GENOMIC VARIATION DATA.

    Science.gov (United States)

    Bhaskar, Anand; Song, Yun S

    2014-01-01

    The sample frequency spectrum (SFS) is a widely-used summary statistic of genomic variation in a sample of homologous DNA sequences. It provides a highly efficient dimensional reduction of large-scale population genomic data and its mathematical dependence on the underlying population demography is well understood, thus enabling the development of efficient inference algorithms. However, it has been recently shown that very different population demographies can actually generate the same SFS for arbitrarily large sample sizes. Although in principle this nonidentifiability issue poses a thorny challenge to statistical inference, the population size functions involved in the counterexamples are arguably not so biologically realistic. Here, we revisit this problem and examine the identifiability of demographic models under the restriction that the population sizes are piecewise-defined where each piece belongs to some family of biologically-motivated functions. Under this assumption, we prove that the expected SFS of a sample uniquely determines the underlying demographic model, provided that the sample is sufficiently large. We obtain a general bound on the sample size sufficient for identifiability; the bound depends on the number of pieces in the demographic model and also on the type of population size function in each piece. In the cases of piecewise-constant, piecewise-exponential and piecewise-generalized-exponential models, which are often assumed in population genomic inferences, we provide explicit formulas for the bounds as simple functions of the number of pieces. Lastly, we obtain analogous results for the "folded" SFS, which is often used when there is ambiguity as to which allelic type is ancestral. Our results are proved using a generalization of Descartes' rule of signs for polynomials to the Laplace transform of piecewise continuous functions.

  7. DESCARTES’ RULE OF SIGNS AND THE IDENTIFIABILITY OF POPULATION DEMOGRAPHIC MODELS FROM GENOMIC VARIATION DATA1

    Science.gov (United States)

    Bhaskar, Anand; Song, Yun S.

    2016-01-01

    The sample frequency spectrum (SFS) is a widely-used summary statistic of genomic variation in a sample of homologous DNA sequences. It provides a highly efficient dimensional reduction of large-scale population genomic data and its mathematical dependence on the underlying population demography is well understood, thus enabling the development of efficient inference algorithms. However, it has been recently shown that very different population demographies can actually generate the same SFS for arbitrarily large sample sizes. Although in principle this nonidentifiability issue poses a thorny challenge to statistical inference, the population size functions involved in the counterexamples are arguably not so biologically realistic. Here, we revisit this problem and examine the identifiability of demographic models under the restriction that the population sizes are piecewise-defined where each piece belongs to some family of biologically-motivated functions. Under this assumption, we prove that the expected SFS of a sample uniquely determines the underlying demographic model, provided that the sample is sufficiently large. We obtain a general bound on the sample size sufficient for identifiability; the bound depends on the number of pieces in the demographic model and also on the type of population size function in each piece. In the cases of piecewise-constant, piecewise-exponential and piecewise-generalized-exponential models, which are often assumed in population genomic inferences, we provide explicit formulas for the bounds as simple functions of the number of pieces. Lastly, we obtain analogous results for the “folded” SFS, which is often used when there is ambiguity as to which allelic type is ancestral. Our results are proved using a generalization of Descartes’ rule of signs for polynomials to the Laplace transform of piecewise continuous functions. PMID:28018011

  8. Structured Modeling and Analysis of Stochastic Epidemics with Immigration and Demographic Effects.

    Science.gov (United States)

    Baumann, Hendrik; Sandmann, Werner

    2016-01-01

    Stochastic epidemics with open populations of variable population sizes are considered where due to immigration and demographic effects the epidemic does not eventually die out forever. The underlying stochastic processes are ergodic multi-dimensional continuous-time Markov chains that possess unique equilibrium probability distributions. Modeling these epidemics as level-dependent quasi-birth-and-death processes enables efficient computations of the equilibrium distributions by matrix-analytic methods. Numerical examples for specific parameter sets are provided, which demonstrates that this approach is particularly well-suited for studying the impact of varying rates for immigration, births, deaths, infection, recovery from infection, and loss of immunity.

  9. Structured Modeling and Analysis of Stochastic Epidemics with Immigration and Demographic Effects.

    Directory of Open Access Journals (Sweden)

    Hendrik Baumann

    Full Text Available Stochastic epidemics with open populations of variable population sizes are considered where due to immigration and demographic effects the epidemic does not eventually die out forever. The underlying stochastic processes are ergodic multi-dimensional continuous-time Markov chains that possess unique equilibrium probability distributions. Modeling these epidemics as level-dependent quasi-birth-and-death processes enables efficient computations of the equilibrium distributions by matrix-analytic methods. Numerical examples for specific parameter sets are provided, which demonstrates that this approach is particularly well-suited for studying the impact of varying rates for immigration, births, deaths, infection, recovery from infection, and loss of immunity.

  10. Consequences of the genetic threshold model for observing partial migration under climate change scenarios.

    Science.gov (United States)

    Cobben, Marleen M P; van Noordwijk, Arie J

    2017-10-01

    Migration is a widespread phenomenon across the animal kingdom as a response to seasonality in environmental conditions. Partially migratory populations are populations that consist of both migratory and residential individuals. Such populations are very common, yet their stability has long been debated. The inheritance of migratory activity is currently best described by the threshold model of quantitative genetics. The inclusion of such a genetic threshold model for migratory behavior leads to a stable zone in time and space of partially migratory populations under a wide range of demographic parameter values, when assuming stable environmental conditions and unlimited genetic diversity. Migratory species are expected to be particularly sensitive to global warming, as arrival at the breeding grounds might be increasingly mistimed as a result of the uncoupling of long-used cues and actual environmental conditions, with decreasing reproduction as a consequence. Here, we investigate the consequences for migratory behavior and the stability of partially migratory populations under five climate change scenarios and the assumption of a genetic threshold value for migratory behavior in an individual-based model. The results show a spatially and temporally stable zone of partially migratory populations after different lengths of time in all scenarios. In the scenarios in which the species expands its range from a particular set of starting populations, the genetic diversity and location at initialization determine the species' colonization speed across the zone of partial migration and therefore across the entire landscape. Abruptly changing environmental conditions after model initialization never caused a qualitative change in phenotype distributions, or complete extinction. This suggests that climate change-induced shifts in species' ranges as well as changes in survival probabilities and reproductive success can be met with flexibility in migratory behavior at the

  11. Using Patient Demographics and Statistical Modeling to Predict Knee Tibia Component Sizing in Total Knee Arthroplasty.

    Science.gov (United States)

    Ren, Anna N; Neher, Robert E; Bell, Tyler; Grimm, James

    2018-06-01

    Preoperative planning is important to achieve successful implantation in primary total knee arthroplasty (TKA). However, traditional TKA templating techniques are not accurate enough to predict the component size to a very close range. With the goal of developing a general predictive statistical model using patient demographic information, ordinal logistic regression was applied to build a proportional odds model to predict the tibia component size. The study retrospectively collected the data of 1992 primary Persona Knee System TKA procedures. Of them, 199 procedures were randomly selected as testing data and the rest of the data were randomly partitioned between model training data and model evaluation data with a ratio of 7:3. Different models were trained and evaluated on the training and validation data sets after data exploration. The final model had patient gender, age, weight, and height as independent variables and predicted the tibia size within 1 size difference 96% of the time on the validation data, 94% of the time on the testing data, and 92% on a prospective cadaver data set. The study results indicated the statistical model built by ordinal logistic regression can increase the accuracy of tibia sizing information for Persona Knee preoperative templating. This research shows statistical modeling may be used with radiographs to dramatically enhance the templating accuracy, efficiency, and quality. In general, this methodology can be applied to other TKA products when the data are applicable. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. Fear of crime in Belgrade: Testing a socio-demographic and social-psychological factors model

    Directory of Open Access Journals (Sweden)

    Popović-Ćitić Branislava

    2014-01-01

    Full Text Available Despite a wealth of research practice, the conceptualization of fear of crime and the ways in which this fear is measured remain the subject of intense theoretical debate in criminological and sociological disciplines. Taking as a starting point the need for a theoretical explanation of fear of crime and the existing research which has confirmed the relevance of the model which integrates socio-demographic and social-psychological factors, a study was conducted in order to examine the predictive capabilities of these factors and compare the results with those of similar studies in the region. The analysis was based on the data obtained in the course of the regional research project 'Fear of Crime in Large Cities', carried out in 2009 in the capital cities of former Yugoslav republics on a multistage random sample using the method of in-home interview. A hierarchical multiple regression analysis was applied on a sample of 397 adult respondents residing in urban parts of Belgrade in order to draw conclusions on how the variables of the integrated model can help explain the differences in the level of fear of crime. Fear of crime, as a dependent variable, was measured using six vignettes after the reliability and unidimensionality of the construct was confirmed. The results of the regression analysis showed that the proposed model was able to account for 42% of the differences in fear of crime. With regard to the socio-demographic variables (introduced in the first step and accounting for 31% of the variance, it was determined that women express the greatest fear of crime as they avoid being alone in their neighbourhoods at night, visit nearby friends less frequently and believe that the streets, shops, and woods in their immediate surroundings are not safe. Regarding the social-psychological variables (which accounted for the additional 11% of the variance, a higher level of fear was found in persons who believe that other people pose a threat to

  13. Predictive model for functional consequences of oral cavity tumour resections

    NARCIS (Netherlands)

    van Alphen, M.J.A.; Hageman, T.A.G.; Hageman, Tijmen Antoon Geert; Smeele, L.E.; Balm, Alfonsus Jacobus Maria; Balm, A.J.M.; van der Heijden, Ferdinand; Lemke, H.U.

    2013-01-01

    The prediction of functional consequences after treatment of large oral cavity tumours is mainly based on the size and location of the tumour. However, patient specific factors play an important role in the functional outcome, making the current predictions unreliable and subjective. An objective

  14. Global economic consequences of selected surgical diseases: a modelling study.

    Science.gov (United States)

    Alkire, Blake C; Shrime, Mark G; Dare, Anna J; Vincent, Jeffrey R; Meara, John G

    2015-04-27

    The surgical burden of disease is substantial, but little is known about the associated economic consequences. We estimate the global macroeconomic impact of the surgical burden of disease due to injury, neoplasm, digestive diseases, and maternal and neonatal disorders from two distinct economic perspectives. We obtained mortality rate estimates for each disease for the years 2000 and 2010 from the Institute of Health Metrics and Evaluation Global Burden of Disease 2010 study, and estimates of the proportion of the burden of the selected diseases that is surgical from a paper by Shrime and colleagues. We first used the value of lost output (VLO) approach, based on the WHO's Projecting the Economic Cost of Ill-Health (EPIC) model, to project annual market economy losses due to these surgical diseases during 2015-30. EPIC attempts to model how disease affects a country's projected labour force and capital stock, which in turn are related to losses in economic output, or gross domestic product (GDP). We then used the value of lost welfare (VLW) approach, which is conceptually based on the value of a statistical life and is inclusive of non-market losses, to estimate the present value of long-run welfare losses resulting from mortality and short-run welfare losses resulting from morbidity incurred during 2010. Sensitivity analyses were performed for both approaches. During 2015-30, the VLO approach projected that surgical conditions would result in losses of 1·25% of potential GDP, or $20·7 trillion (2010 US$, purchasing power parity) in the 128 countries with data available. When expressed as a proportion of potential GDP, annual GDP losses were greatest in low-income and middle-income countries, with up to a 2·5% loss in output by 2030. When total welfare losses are assessed (VLW), the present value of economic losses is estimated to be equivalent to 17% of 2010 GDP, or $14·5 trillion in the 175 countries assessed with this approach. Neoplasm and injury account

  15. Evaluating mechanisms of diversification in a Guineo-Congolian tropical forest frog using demographic model selection.

    Science.gov (United States)

    Portik, Daniel M; Leaché, Adam D; Rivera, Danielle; Barej, Michael F; Burger, Marius; Hirschfeld, Mareike; Rödel, Mark-Oliver; Blackburn, David C; Fujita, Matthew K

    2017-10-01

    The accumulation of biodiversity in tropical forests can occur through multiple allopatric and parapatric models of diversification, including forest refugia, riverine barriers and ecological gradients. Considerable debate surrounds the major diversification process, particularly in the West African Lower Guinea forests, which contain a complex geographic arrangement of topographic features and historical refugia. We used genomic data to investigate alternative mechanisms of diversification in the Gaboon forest frog, Scotobleps gabonicus, by first identifying population structure and then performing demographic model selection and spatially explicit analyses. We found that a majority of population divergences are best explained by allopatric models consistent with the forest refugia hypothesis and involve divergence in isolation with subsequent expansion and gene flow. These population divergences occurred simultaneously and conform to predictions based on climatically stable regions inferred through ecological niche modelling. Although forest refugia played a prominent role in the intraspecific diversification of S. gabonicus, we also find evidence for potential interactions between landscape features and historical refugia, including major rivers and elevational barriers such as the Cameroonian Volcanic Line. We outline the advantages of using genomewide variation in a model-testing framework to distinguish between alternative allopatric hypotheses, and the pitfalls of limited geographic and molecular sampling. Although phylogeographic patterns are often species-specific and related to life-history traits, additional comparative studies incorporating genomic data are necessary for separating shared historical processes from idiosyncratic responses to environmental, climatic and geological influences on diversification. © 2017 John Wiley & Sons Ltd.

  16. Modeling demographic performance of northern spotted owls relative to forest habitat in Oregon

    Science.gov (United States)

    Olson, Gail S.; Glenn, Elizabeth M.; Anthony, Robert G.; Forsman, Eric D.; Reid, Janice A.; Loschl, Peter J.; Ripple, William J.

    2004-01-01

    Northern spotted owls (Strix occidentalis caurina) are known to be associated with late-successional forests in the Pacific Northwest of the United States, but the effects of habitat on their demographic performance are relatively unknown. We developed statistical models relating owl survival and productivity to forest cover types within the Roseburg Study Area in the Oregon Coast Range of Oregon, USA. We further combined these demographic parameters using a Leslie-type matrix to obtain an estimate of habitat fitness potential for each owl territory (n = 94). We used mark–recapture methods to develop models for survival and linear mixed models for productivity. We measured forest composition and landscape patterns at 3 landscape scales centered on nest and activity sites within owl territories using an aerial photo-based map and a Geographic Information System (GIS). We also considered additional covariates such as age, sex, and presence of barred owls (Strix varia), and seasonal climate variables (temperature and precipitation) in our models. We used Akaike's Information Criterion (AIC) to rank and compare models. Survival had a quadratic relationship with the amount of late- and mid-seral forests within 1,500 m of nesting centers. Survival also was influenced by the amount of precipitation during the nesting season. Only 16% of the variability in survival was accounted for by our best model, but 85% of this was due to the habitat variable. Reproductive rates fluctuated biennially and were positively related to the amount of edge between late- and mid-seral forests and other habitat classes. Reproductive rates also were influenced by parent age, amount of precipitation during nesting season, and presence of barred owls. Our best model accounted for 84% of the variability in productivity, but only 3% of that was due to the habitat variable. Estimates of habitat fitness potential (which may range from 0 to infinity) for the 94 territories ranged from 0.74 to 1

  17. Demographic origins of skewed operational and adult sex ratios: perturbation analyses of two-sex models.

    Science.gov (United States)

    Veran, Sophie; Beissinger, Steven R

    2009-02-01

    Skewed sex ratios - operational (OSR) and Adult (ASR) - arise from sexual differences in reproductive behaviours and adult survival rates due to the cost of reproduction. However, skewed sex-ratio at birth, sex-biased dispersal and immigration, and sexual differences in juvenile mortality may also contribute. We present a framework to decompose the roles of demographic traits on sex ratios using perturbation analyses of two-sex matrix population models. Metrics of sensitivity are derived from analyses of sensitivity, elasticity, life-table response experiments and life stage simulation analyses, and applied to the stable stage distribution instead of lambda. We use these approaches to examine causes of male-biased sex ratios in two populations of green-rumped parrotlets (Forpus passerinus) in Venezuela. Female local juvenile survival contributed the most to the unbalanced OSR and ASR due to a female-biased dispersal rate, suggesting sexual differences in philopatry can influence sex ratios more strongly than the cost of reproduction.

  18. Processing Expert Judgements in Accident Consequence Modelling (invited paper)

    International Nuclear Information System (INIS)

    Kraan, B.C.P.; Cooke, R.M.

    2000-01-01

    In performing uncertainty analysis a distribution on the code input parameters is required. The construction of the distribution on the code input parameters for the joint CEC/USNRC Accident Consequence Code Uncertainty Analysis using Expert Judgement is discussed. An example from the food chain module is used to illustrate the construction. Different mathematical techniques have been developed to transform the expert judgements into the required format. Finally, the effect of taking account of correlations in performing uncertainty analysis is investigated. (author)

  19. Ex-plant consequence assessment for NUREG-1150: models, typical results, uncertainties

    International Nuclear Information System (INIS)

    Sprung, J.L.

    1988-01-01

    The assessment of ex-plant consequences for NUREG-1150 source terms was performed using the MELCOR Accident Consequence Code System (MACCS). This paper briefly discusses the following elements of MACCS consequence calculations: input data, phenomena modeled, computational framework, typical results, controlling phenomena, and uncertainties. Wherever possible, NUREG-1150 results will be used to illustrate the discussion. 28 references

  20. Effects of wind shear on the consequence model of the reactor safety study

    International Nuclear Information System (INIS)

    Sprung, J.L.; Church, H.W.

    1977-01-01

    The effects of explicit incorporation of wind shear into the consequence model of the Reactor Safety study have been investigated. The integral of exposure (X/Q) over area is unchanged by directional shear and decreased by speed shear. Consequence model predictions of early fatalities are always decreased by wind shear. Where early fatalities are decreased, survivors are subject to latent effects and, therefore, latent effects increase. However, aggregate early fatalities and latent effects always are decreased. Because the magnitude of these changes is within the present uncertainties of the consequence model, explicit incorporation of wind shear in the consequence model is not now warranted

  1. The importance of trajectory modelling in accident consequence assessments

    International Nuclear Information System (INIS)

    Jones, J.A.; Williams, J.A.; Hill, M.D.

    1988-01-01

    Most atmospheric dispersion models used at present or probabilistic risk assessment (PRA) are linear: they take account of the wind speed but not the direction after the first hour. Therefore, the trajectory model is a more realistic description of the cloud's behaviour. However, the extra complexity means that the computing costs increase. This is an important factor for the MARIA code which is intended to be run on computers of varying power. The numbers of early effects predicted by a linear model and a trajectory model in a probabilistic risk assessment were compared to see which model should be preferred. The trajectory model predicted about 25% fewer expected early deaths and 30% more people evacuated than the linear model. However, the trajectory model took about ten times longer to calculate its results. The choice between the two models may depend on the speed of the computer available

  2. Aspects of uncertainty analysis in accident consequence modeling

    International Nuclear Information System (INIS)

    Travis, C.C.; Hoffman, F.O.

    1981-01-01

    Mathematical models are frequently used to determine probable dose to man from an accidental release of radionuclides by a nuclear facility. With increased emphasis on the accuracy of these models, the incorporation of uncertainty analysis has become one of the most crucial and sensitive components in evaluating the significance of model predictions. In the present paper, we address three aspects of uncertainty in models used to assess the radiological impact to humans: uncertainties resulting from the natural variability in human biological parameters; the propagation of parameter variability by mathematical models; and comparison of model predictions to observational data

  3. Decision model on the demographic profile for tuberculosis control using fuzzy logic

    Directory of Open Access Journals (Sweden)

    Laisa Ribeiro de Sá

    2015-06-01

    Full Text Available This study aimed to describe the relationship between demographic factors and the involvement of tuberculosis by applying a decision support model based on fuzzy logic to classify the regions as priority and non-priority in the city of João Pessoa, state of Paraíba (PB. As data source, we used the Notifiable Diseases Information System between 2009 and 2011. We chose the descriptive analysis, relative risk (RR, spatial distribution and fuzzy logic. The total of 1,245 cases remained in the study, accounting for 37.02% of cases in 2009. High and low risk clusters were identified, and the RR was higher among men (8.47, with 12 clusters, and among those uneducated (11.65, with 13 clusters. To demonstrate the functionality of the model was elected the year with highest number of cases, and the municipality district with highest population. The methodology identified priority areas, guiding managers to make decisions that respect the local particularities.

  4. Demographic models and IPCC climate projections predict the decline of an emperor penguin population

    Science.gov (United States)

    Jenouvrier, Stéphanie; Caswell, Hal; Barbraud, Christophe; Holland, Marika; Strœve, Julienne; Weimerskirch, Henri

    2009-01-01

    Studies have reported important effects of recent climate change on Antarctic species, but there has been to our knowledge no attempt to explicitly link those results to forecasted population responses to climate change. Antarctic sea ice extent (SIE) is projected to shrink as concentrations of atmospheric greenhouse gases (GHGs) increase, and emperor penguins (Aptenodytes forsteri) are extremely sensitive to these changes because they use sea ice as a breeding, foraging and molting habitat. We project emperor penguin population responses to future sea ice changes, using a stochastic population model that combines a unique long-term demographic dataset (1962–2005) from a colony in Terre Adélie, Antarctica and projections of SIE from General Circulation Models (GCM) of Earth's climate included in the most recent Intergovernmental Panel on Climate Change (IPCC) assessment report. We show that the increased frequency of warm events associated with projected decreases in SIE will reduce the population viability. The probability of quasi-extinction (a decline of 95% or more) is at least 36% by 2100. The median population size is projected to decline from ≈6,000 to ≈400 breeding pairs over this period. To avoid extinction, emperor penguins will have to adapt, migrate or change the timing of their growth stages. However, given the future projected increases in GHGs and its effect on Antarctic climate, evolution or migration seem unlikely for such long lived species at the remote southern end of the Earth. PMID:19171908

  5. Pseudoplastic dynamical model of the asthenosphere and its tectonic consequences

    International Nuclear Information System (INIS)

    Reju, S.A.

    1990-11-01

    Recent geophysical investigations show that the asthenosphere is more of a plastic continuum of the earth's interior. Thus Newtonian models are far from depicting the characteristics of motion within the earth's mantle. This paper in particular formulates and analyses pseudoplastic models, especially for a rather vital region of the asthenosphere, namely, the polymorphic region between the lithosphere and the real asthenosphere. (author). 5 refs

  6. Use of nonlinear dose-effect models to predict consequences

    International Nuclear Information System (INIS)

    Seiler, F.A.; Alvarez, J.L.

    1996-01-01

    The linear dose-effect relationship was introduced as a model for the induction of cancer from exposure to nuclear radiation. Subsequently, it has been used by analogy to assess the risk of chemical carcinogens also. Recently, however, the model for radiation carcinogenesis has come increasingly under attack because its calculations contradict the epidemiological data, such as cancer in atomic bomb survivors. Even so, its proponents vigorously defend it, often using arguments that are not so much scientific as a mix of scientific, societal, and often political arguments. At least in part, the resilience of the linear model is due to two convenient properties that are exclusive to linearity: First, the risk of an event is determined solely by the event dose; second, the total risk of a population group depends only on the total population dose. In reality, the linear model has been conclusively falsified; i.e., it has been shown to make wrong predictions, and once this fact is generally realized, the scientific method calls for a new paradigm model. As all alternative models are by necessity nonlinear, all the convenient properties of the linear model are invalid, and calculational procedures have to be used that are appropriate for nonlinear models

  7. Consequences of population models on the dynamics of food chains.

    NARCIS (Netherlands)

    Kooi, B.W.; Boer, M.P.; Kooijman, S.A.L.M.

    1998-01-01

    A class of bioenergetic ecological models is studied for the dynamics of food chains with a nutrient at the base. A constant influx rate of the nutrient and a constant efflux rate for all trophic levels is assumed. Starting point is a simple model where prey is converted into predator with a fixed

  8. Consequences of Work-Family Conflict: Testing a New Model of Work-Related, Non-Work-Related and Sress-Related Outcomes

    OpenAIRE

    Esson, Patrice L.

    2004-01-01

    With the demographic layout of the workplace changing constantly, as more women enter the workforce, and as new organizational hiring practices lead to more diversity in the work environment, both researchers and employers have become increasingly interested in understanding the consequences of work-family conflict. Work-family conflict affects the individuals suffering from it, their families, and their employers. Thus, it is important to have a robust and comprehensive causal model that exp...

  9. 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.

  10. Demographic Models for Projecting Population and Migration: Methods for African Historical Analysis

    Directory of Open Access Journals (Sweden)

    Patrick Manning

    2015-08-01

    Full Text Available This study presents methods for projecting population and migration over time in cases were empirical data are missing or undependable. The methods are useful for cases in which the researcher has details of population size and structure for a limited period of time (most obviously, the end point, with scattered evidence on other times. It enables estimation of population size, including its structure in age, sex, and status, either forward or backward in time. The program keeps track of all the details. The calculated data can be reported or sampled and compared to empirical findings at various times and places to expected values based on other procedures of estimation. The application of these general methods that is developed here is the projection of African populations backwards in time from 1950, since 1950 is the first date for which consistently strong demographic estimates are available for national-level populations all over the African continent. The models give particular attention to migration through enslavement, which was highly important in Africa from 1650 to 1900. Details include a sensitivity analysis showing relative significance of input variables and techniques for calibrating various dimensions of the projection with each other. These same methods may be applicable to quite different historical situations, as long as the data conform in structure to those considered here.

  11. Demographic trade-offs in a neutral model explain death-rate--abundance-rank relationship.

    Science.gov (United States)

    Lin, Kui; Zhang, Da-Yong; He, Fangliang

    2009-01-01

    The neutral theory of biodiversity has been criticized for its neglect of species differences. Yet it is much less heeded that S. P. Hubbell's definition of neutrality allows species to differ in their birth and death rates as long as they have an equal per capita fitness. Using the lottery model of competition we find that fitness equalization through birth-death trade-offs can make species coexist longer than expected for demographically identical species, whereas the probability of monodominance for a species under zero-sum neutral dynamics is equal to its initial relative abundance. Furthermore, if newly arising species in a community survive preferentially they are more likely to slip through the quagmire of rareness, thus creating a strong selective bias favoring their community membership. On the other hand, high-mortality species, once having gained a footing in the community, are more likely to become abundant due to their compensatory high birth rates. This unexpected result explains why a positive association between species abundance and per capita death rate can be seen in tropical-forest communities. An explicit incorporation of interspecific trade-offs between birth and death into the neutral theory increases the theory's realism as well as its predictive power.

  12. Demographic factors and traffic crashes. Part 1, descriptive statistics and models

    Science.gov (United States)

    1998-08-01

    This research analyzes the Department of Highway Safety and Motor Vehicle's (DHSMV) 1993 to 1995 crash data. There are four demographic variables investigated throughout the research, which are age, gender, race, and residency. To show general trends...

  13. Das causas às conseqüências econômicas da transição demográfica no Brasil From the causes to the economic consequences of the demographic transition in Brazil

    Directory of Open Access Journals (Sweden)

    Paulo de Tarso Almeida Paiva

    2005-12-01

    Full Text Available As relações entre crescimento populacional e desenvolvimento desafiam estudiosos por muito tempo e referem-se tanto aos impactos do crescimento e estrutura da população sobre o crescimento e a distribuição da renda (crescimento econômico, quanto sobre os impactos do crescimento econômico sobre o crescimento e a estrutura da população. Há cerca de três décadas discutiam-se as causas e conseqüências do crescimento populacional. Hoje, discutem-se as causas e conseqüências da transição demográfica. Muita coisa mudou no mundo e, do ponto de vista demográfico, a maior mudança foi a universalização do processo de transição demográfica. Expressões como "bomba demográfica" foram substituídas por "bônus demográfico" ou "janela de oportunidades". Este artigo pretende examinar como essas relações entre população e economia foram interpretadas e discutidas e como influenciaram o pensamento, a pesquisa acadêmica e, eventualmente, algumas propostas de políticas públicas no Brasil. O artigo procura sumariar os avanços que estão em curso na pesquisa sobre população e economia e suas implicações para as políticas públicas e o desenvolvimento.Relationships between development and population growth have challenged scholars and researchers for many years, and refer to the impacts of population growth and distribution on economic growth, and to the impacts of economic growth on population. Three decades ago the major issue was the causes and consequences of population growth. The central issue today is about the causes and consequences of demographic transition on the economy. Many changes have taken place over the last thirty years. From the demographic point of view, the most important change has been the generalization of the so-called demographic transition. "Demographic bonus" and "window of opportunities" have become substitutes for "the demographic bomb." This article describes how the relations between population

  14. Consequences of spatial autocorrelation for niche-based models

    DEFF Research Database (Denmark)

    Segurado, P.; Araújo, Miguel B.; Kunin, W. E.

    2006-01-01

    1.  Spatial autocorrelation is an important source of bias in most spatial analyses. We explored the bias introduced by spatial autocorrelation on the explanatory and predictive power of species' distribution models, and make recommendations for dealing with the problem. 2.  Analyses were based o...

  15. Consequence of reputation in the Sznajd consensus model

    Science.gov (United States)

    Crokidakis, Nuno; Forgerini, Fabricio L.

    2010-07-01

    In this work we study a modified version of the Sznajd sociophysics model. In particular we introduce reputation, a mechanism that limits the capacity of persuasion of the agents. The reputation is introduced as a score which is time-dependent, and its introduction avoid dictatorship (all spins parallel) for a wide range of parameters. The relaxation time follows a log-normal-like distribution. In addition, we show that the usual phase transition also occurs, as in the standard model, and it depends on the initial concentration of individuals following an opinion, occurring at a initial density of up spins greater than 1/2. The transition point is determined by means of a finite-size scaling analysis.

  16. Consequence of reputation in the Sznajd consensus model

    International Nuclear Information System (INIS)

    Crokidakis, Nuno; Forgerini, Fabricio L.

    2010-01-01

    In this work we study a modified version of the Sznajd sociophysics model. In particular we introduce reputation, a mechanism that limits the capacity of persuasion of the agents. The reputation is introduced as a score which is time-dependent, and its introduction avoid dictatorship (all spins parallel) for a wide range of parameters. The relaxation time follows a log-normal-like distribution. In addition, we show that the usual phase transition also occurs, as in the standard model, and it depends on the initial concentration of individuals following an opinion, occurring at a initial density of up spins greater than 1/2. The transition point is determined by means of a finite-size scaling analysis.

  17. Consequence of reputation in the Sznajd consensus model

    Energy Technology Data Exchange (ETDEWEB)

    Crokidakis, Nuno [Instituto de Fisica, Universidade Federal Fluminense, Av. Litoranea s/n, 24210-340 Niteroi, RJ (Brazil); Departamento de Fisica, I3N - Universidade de Aveiro, 3810-193 Aveiro (Portugal); Forgerini, Fabricio L., E-mail: fabricio_forgerini@ufam.edu.b [Departamento de Fisica, I3N - Universidade de Aveiro, 3810-193 Aveiro (Portugal); ISB - Universidade Federal do Amazonas, 69460-000 Coari, AM (Brazil)

    2010-07-26

    In this work we study a modified version of the Sznajd sociophysics model. In particular we introduce reputation, a mechanism that limits the capacity of persuasion of the agents. The reputation is introduced as a score which is time-dependent, and its introduction avoid dictatorship (all spins parallel) for a wide range of parameters. The relaxation time follows a log-normal-like distribution. In addition, we show that the usual phase transition also occurs, as in the standard model, and it depends on the initial concentration of individuals following an opinion, occurring at a initial density of up spins greater than 1/2. The transition point is determined by means of a finite-size scaling analysis.

  18. Probabilistic consequence model of accidenal or intentional chemical releases.

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Y.-S.; Samsa, M. E.; Folga, S. M.; Hartmann, H. M.

    2008-06-02

    In this work, general methodologies for evaluating the impacts of large-scale toxic chemical releases are proposed. The potential numbers of injuries and fatalities, the numbers of hospital beds, and the geographical areas rendered unusable during and some time after the occurrence and passage of a toxic plume are estimated on a probabilistic basis. To arrive at these estimates, historical accidental release data, maximum stored volumes, and meteorological data were used as inputs into the SLAB accidental chemical release model. Toxic gas footprints from the model were overlaid onto detailed population and hospital distribution data for a given region to estimate potential impacts. Output results are in the form of a generic statistical distribution of injuries and fatalities associated with specific toxic chemicals and regions of the United States. In addition, indoor hazards were estimated, so the model can provide contingency plans for either shelter-in-place or evacuation when an accident occurs. The stochastic distributions of injuries and fatalities are being used in a U.S. Department of Homeland Security-sponsored decision support system as source terms for a Monte Carlo simulation that evaluates potential measures for mitigating terrorist threats. This information can also be used to support the formulation of evacuation plans and to estimate damage and cleanup costs.

  19. Gender consequences of a national performance-based funding model

    DEFF Research Database (Denmark)

    Nielsen, Mathias Wullum

    2017-01-01

    -regarded’ and highly selective journals and book publishers, and 1 and 5 points for equivalent scientific contributions via ‘normal level’ channels. On the basis of bibliometric data, the study shows that the BRI considerably widens the existing gender gap in researcher performance, since men on average receive more......This article investigates the extent to which the Danish Bibliometric Research Indicator (BRI) reflects the performance of men and women differently. The model is based on a differentiated counting of peer-reviewed publications, awarding three and eight points for contributions to ‘well...... privileges collaborative research, which disadvantages women due to gender differences in collaborative network relations....

  20. Identity of organizational conflict framework: Evaluating model factors based on demographic characteristics in Iran

    Directory of Open Access Journals (Sweden)

    Kaveh Hasani

    2014-10-01

    Full Text Available Normal 0 false false false EN-US X-NONE FA Purpose: The purpose of this study was to Identity of organizational conflict framework:  Evaluating model factors based on demographic characteristics in Iran. Design/methodology/approach: Research method is descriptive - applied. The statistical population includes all of the employees in Iran`s Azad Universites with 600 individuals at the time of the study and statistical sample included 234 individuals who were selected using Morgan table. Beside this study, descriptive and inferential statistics were used. Also, reliability approved through Cronbach alpha (0.87. Then, to detect the dimensions causes of organizational conflict, factor analysis in line with the main components was used. Through exploratory analysis, ten principal factors identified. Thereafter, confirmatory factor analysis reconfirmed these factors. Findings and originality/value: The results of study showed that there is no significant difference between the causes of organizational conflict based on the gender. Also, there are significant differences among the causes of organizational conflict based on the variables of age, education and work experience. Research limitations/implications: we adopt a cross sectional research design and as a result inferences regarding causality cannot be drawn. Future studies following a longitudinal design could provide a more dynamic perspective and contribute further to this stream of research. Originality/value: A lot of researches about the conflict management styles, organizational conflict's effects, etc. are conducted by different researchers, but a handful of researches have been conducted in the field of resources and causes of organizational conflict and this is one of the reasons that it is important for researchers to address this issue.

  1. Economic implications of Japan's aging population: a macro-economic demographic modeling approach.

    Science.gov (United States)

    Ogawa, N

    1982-01-01

    This paper utilizes a macroeconomic demographic model to analyze the probable impact of population aging on various public programs in Japan. Rapid fertility decline aided by mortality decline has caused the proportion of the Japanese population aged 65 and over to increase from 4.9% in 1950 to 9.0% in 1980. A population projection based on the 1975 population census assumes a recovery of fertility from a total fertility rate (TFR) of 1.9 in 1976 to 2.16 in 1980 and a gradual decline to 2.1 by 1987, while an alternative projection assumes a continuing fertility decline to a TFR of 1.65 in 2025. According to these assumptions, in 2025 18.12% to 21.29% of the total population would be aged 65 or over and 38.66% to 43.80% of the working age population would be aged 45-64. A macroeconomic neoclassical growth model with some Keynesian features was formulated to evaluate the future impact of population aging on social security programs. Population changes are transmitted to economic variables in the model through the supply of labor, level of savings, public health care plans, and old-age pension schemes. The simulation experiments included the 2 population projections and 2 alternative production functions, 1 with the quality of labor incorporated and 1 without. The results indicated that, regardless of the population projection and production function used, the growth of the economy is likely to slow to 1 or 0% in the beginning of the next century due to decreased growth of the labor force and a change in its quality due to age-compositional variations. Public health insurance schemes and pension plans will require increasing financial resources as a result of accelerated population aging; depending on the choice of benefit levels, the proportion of national income allocated to them is expected to range from 14%-40% in the year 2010. Per capita gross national product will continue to grow despite decreased economic growth, but savings might be adversely affected if the

  2. Modelling the economic consequences of Marine Protected Areas using the BEMCOM model

    DEFF Research Database (Denmark)

    Hoff, A.; Andersen, J.L.; Christensen, Asbjørn

    2013-01-01

    the question ‘what’s best?’, i.e. finds the overall optimal effort allocation, from an economic point of view, between multiple harvesting fleets fishing under a subset of restrictions on catches and effort levels. The BEMCOM model is described and applied to the case of the Danish sandeel fishery in the North......This paper introduces and describes in detail the bioeconomic optimization model BEMCOM (BioEconomic Model to evaluate the COnsequences of Marine protected areas) that has been developed to assess the economic effects of introducing Marine Protected Areas (MPA) for fisheries. BEMCOM answers...... Sea. It has several times been suggested to close parts of the sandeel fishery in the North Sea out of concern for other species feeding on sandeel and/or spawning in the sandeel habitats. The economic effects of such closures have been assessed using BEMCOM. The results indicate that the model yields...

  3. Postural Consequences of Cervical Sagittal Imbalance: A Novel Laboratory Model.

    Science.gov (United States)

    Patwardhan, Avinash G; Havey, Robert M; Khayatzadeh, Saeed; Muriuki, Muturi G; Voronov, Leonard I; Carandang, Gerard; Nguyen, Ngoc-Lam; Ghanayem, Alexander J; Schuit, Dale; Patel, Alpesh A; Smith, Zachary A; Sears, William

    2015-06-01

    A biomechanical study using human spine specimens. To study postural compensations in lordosis angles that are necessary to maintain horizontal gaze in the presence of forward head posture and increasing T1 sagittal tilt. Forward head posture relative to the shoulders, assessed radiographically using the horizontal offset distance between the C2 and C7 vertebral bodies (C2-C7 [sagittal vertical alignment] SVA), is a measure of global cervical imbalance. This may result from kyphotic alignment of cervical segments, muscle imbalance, as well as malalignment of thoracolumbar spine. Ten cadaveric cervical spines (occiput-T1) were tested. The T1 vertebra was anchored to a tilting and translating base. The occiput was free to move vertically but its angular orientation was constrained to ensure horizontal gaze regardless of sagittal imbalance. A 5-kg mass was attached to the occiput to mimic head weight. Forward head posture magnitude and T1 tilt were varied and motions of individual vertebrae were measured to calculate C2-C7 SVA and lordosis across C0-C2 and C2-C7. Increasing C2-C7 SVA caused flexion of lower cervical (C2-C7) segments and hyperextension of suboccipital (C0-C1-C2) segments to maintain horizontal gaze. Increasing kyphotic T1 tilt primarily increased lordosis across the C2-C7 segments. Regression models were developed to predict the compensatory C0-C2 and C2-C7 angulation needed to maintain horizontal gaze given values of C2-C7 SVA and T1 tilt. This study established predictive relationships between radiographical measures of forward head posture, T1 tilt, and postural compensations in the cervical lordosis angles needed to maintain horizontal gaze. The laboratory model predicted that normalization of C2-C7 SVA will reduce suboccipital (C0-C2) hyperextension, whereas T1 tilt reduction will reduce the hyperextension in the C2-C7 segments. The predictive relationships may help in planning corrective strategy in patients experiencing neck pain, which may be

  4. ITER transient consequences for material damage: modelling versus experiments

    International Nuclear Information System (INIS)

    Bazylev, B; Janeschitz, G; Landman, I; Pestchanyi, S; Loarte, A; Federici, G; Merola, M; Linke, J; Zhitlukhin, A; Podkovyrov, V; Klimov, N; Safronov, V

    2007-01-01

    Carbon-fibre composite (CFC) and tungsten macrobrush armours are foreseen as PFC for the ITER divertor. In ITER the main mechanisms of metallic armour damage remain surface melting and melt motion erosion. In the case of CFC armour, due to rather different heat conductivities of CFC fibres a noticeable erosion of the PAN bundles may occur at rather small heat loads. Experiments carried out in the plasma gun facilities QSPA-T for the ITER like edge localized mode (ELM) heat load also demonstrated significant erosion of the frontal and lateral brush edges. Numerical simulations of the CFC and tungsten (W) macrobrush target damage accounting for the heat loads at the face and lateral brush edges were carried out for QSPA-T conditions using the three-dimensional (3D) code PHEMOBRID. The modelling results of CFC damage are in a good qualitative and quantitative agreement with the experiments. Estimation of the droplet splashing caused by the Kelvin-Helmholtz (KH) instability was performed

  5. Statistical challenges in modelling the health consequences of social mobility: the need for diagonal reference models.

    Science.gov (United States)

    van der Waal, Jeroen; Daenekindt, Stijn; de Koster, Willem

    2017-12-01

    Various studies on the health consequences of socio-economic position address social mobility. They aim to uncover whether health outcomes are affected by: (1) social mobility, besides, (2) social origin, and (3) social destination. Conventional methods do not, however, estimate these three effects separately, which may produce invalid conclusions. We highlight that diagonal reference models (DRMs) overcome this problem, which we illustrate by focusing on overweight/obesity (OWOB). Using conventional methods (logistic-regression analyses with dummy variables) and DRMs, we examine the effects of intergenerational educational mobility on OWOB (BMI ≥ 25 kg/m 2 ) using survey data representative of the Dutch population aged 18-45 (1569 males, 1771 females). Conventional methods suggest that mobility effects on OWOB are present. Analyses with DRMs, however, indicate that no such effects exist. Conventional analyses of the health consequences of social mobility may produce invalid results. We, therefore, recommend the use of DRMs. DRMs also validly estimate the health consequences of other types of social mobility (e.g. intra- and intergenerational occupational and income mobility) and status inconsistency (e.g. in educational or occupational attainment between partners).

  6. The use of consequence modelling in assessing accidental releases of activity

    International Nuclear Information System (INIS)

    Clarke, R.H.; Hemming, C.R.; Kelly, G.N.

    1982-01-01

    The radiological consequences of an accidental release can be expressed as the number of health effects in the exposed population and its descendents, and the economic and social implications that may result from restrictions placed on the consumption of foodstuffs, or on the occupation of domestic and commercial premises. For any given release of activity there will be a probability distribution of consequences which will depend on the meteorological characteristics and demographic data particular to the release location. The characteristics of this distribution should be important in reaching judgements on the acceptability of a given site or design. The relative importance of the different endpoints is analysed and the influence of the release location on the resulting distribution is considered. (author)

  7. Impact of rainstorm and runoff modeling on predicted consequences of atmospheric releases from nuclear reactor accidents

    International Nuclear Information System (INIS)

    Ritchie, L.T.; Brown, W.D.; Wayland, J.R.

    1980-05-01

    A general temperate latitude cyclonic rainstorm model is presented which describes the effects of washout and runoff on consequences of atmospheric releases of radioactive material from potential nuclear reactor accidents. The model treats the temporal and spatial variability of precipitation processes. Predicted air and ground concentrations of radioactive material and resultant health consequences for the new model are compared to those of the original WASH-1400 model under invariant meteorological conditions and for realistic weather events using observed meteorological sequences. For a specific accident under a particular set of meteorological conditions, the new model can give significantly different results from those predicted by the WASH-1400 model, but the aggregate consequences produced for a large number of meteorological conditions are similar

  8. The geography of demography: long-term demographic studies and species distribution models reveal a species border limited by adaptation.

    Science.gov (United States)

    Eckhart, V M; Geber, M A; Morris, W F; Fabio, E S; Tiffin, P; Moeller, D A

    2011-10-01

    Potential causes of species' geographic distribution limits fall into two broad classes: (1) limited adaptation across spatially variable environments and (2) limited opportunities to colonize unoccupied areas. Combining demographic studies, analyses of demographic responses to environmental variation, and species distribution models, we investigated the causes of range limits in a model system, the eastern border of the California annual plant Clarkia xantiana ssp. xantiana. Vital rates of 20 populations varied with growing season temperature and precipitation: fruit number and overwinter survival of 1-year-old seeds declined steeply, while current-year seed germination increased modestly along west-to-east gradients in decreasing temperature, decreasing mean precipitation, and increasing variation in precipitation. Long-term stochastic finite rate of increase, λ(s), exhibited a fourfold range and varied among geologic surface materials as well as with temperature and precipitation. Growth rate declined significantly toward the eastern border, falling below 1 in three of the five easternmost populations. Distribution models employing demographically important environmental variables predicted low habitat favorability beyond the eastern border. Models that filtered or weighted population presences by λ(s) predicted steeper eastward declines in favorability and assigned greater roles in setting the distribution to among-year variation in precipitation and to geologic surface material. These analyses reveal a species border likely set by limited adaptation to declining environmental quality.

  9. An integrated modeling approach to estimating Gunnison Sage-Grouse population dynamics: combining index and demographic data.

    Science.gov (United States)

    Davis, Amy J.; Hooten, Mevin B.; Phillips, Michael L.; Doherty, Paul F.

    2014-01-01

    Evaluation of population dynamics for rare and declining species is often limited to data that are sparse and/or of poor quality. Frequently, the best data available for rare bird species are based on large-scale, population count data. These data are commonly based on sampling methods that lack consistent sampling effort, do not account for detectability, and are complicated by observer bias. For some species, short-term studies of demographic rates have been conducted as well, but the data from such studies are typically analyzed separately. To utilize the strengths and minimize the weaknesses of these two data types, we developed a novel Bayesian integrated model that links population count data and population demographic data through population growth rate (λ) for Gunnison sage-grouse (Centrocercus minimus). The long-term population index data available for Gunnison sage-grouse are annual (years 1953–2012) male lek counts. An intensive demographic study was also conducted from years 2005 to 2010. We were able to reduce the variability in expected population growth rates across time, while correcting for potential small sample size bias in the demographic data. We found the population of Gunnison sage-grouse to be variable and slightly declining over the past 16 years.

  10. Stochastic spatio-temporal model of coral cover as a function of herbivorous grazers, water quality, and coral demographics

    Science.gov (United States)

    Neuhausler, R.; Robinson, M.; Bruna, M.

    2017-12-01

    Over the last 60 years we have seen an increased amount of ecological regime shifts in tropical coastal zones, from coral reefs to macroalgae dominated states, as a result of natural and anthropogenic stresses. However, these shifts are not always immediate- macroalgae are generally present in coral reefs, with their distribution regulated by herbivorous fish. This is especially true in Moorea, French Polynesia, where macroalgae are shown to flourish in spaces that provide refuge from roaming herbivores. While there are currently modeling efforts in projecting ecological regime shifts in Moorea, temporal deterministic models have been utilized, which fail to capture metastability between multiple steady states and can have issues when dealing with very small populations. To address these concerns, we build on these models to account for spatial variations and individual organisms, as well as stochasticity. Our model can project the percent cover of coral, macroalgae, and algae turf as a function of herbivorous grazers, water quality, and coral demographics. Grazers, included as individual fish (particles), evolve according to a kinetic model and interact with neighbouring benthic assemblages, represented as nodes. Water quality and coral demographics are input parameters that can vary over time, allowing our model to be run for temporally changing scenarios and to be adjusted for different reefs. We plan to engage with previous Moorea Reef Resilience Models through a comparative analysis of our models' outcomes and existing Moorea data. Coupling projective models with available data is useful for informing environmental policy and advancing the modeling field.

  11. Improving Demographic Components of Integrated Assessment Models: The Effect of Changes in Population Composition by Household Characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Brian C. O' Neill

    2006-08-09

    This report describes results of the research project on "Improving Demographic Components of Integrated Assessment Models: The Effect of Changes in Population Composition by Household Characteristics". The overall objective of this project was to improve projections of energy demand and associated greenhouse gas emissions by taking into account demographic factors currently not incorporated in Integrated Assessment Models (IAMs) of global climate change. We proposed to examine the potential magnitude of effects on energy demand of changes in the composition of populations by household characteristics for three countries: the U.S., China, and Indonesia. For each country, we planned to analyze household energy use survey data to estimate relationships between household characteristics and energy use; develop a new set of detailed household projections for each country; and combine these analyses to produce new projections of energy demand illustrating the potential importance of consideration of households.

  12. The Risoe model for calculating the consequences of the release of radioactive material to the atmosphere

    International Nuclear Information System (INIS)

    Thykier-Nielsen, S.

    1980-07-01

    A brief description is given of the model used at Risoe for calculating the consequences of releases of radioactive material to the atmosphere. The model is based on the Gaussian plume model, and it provides possibilities for calculation of: doses to individuals, collective doses, contamination of the ground, probability distribution of doses, and the consequences of doses for give dose-risk relationships. The model is implemented as a computer program PLUCON2, written in ALGOL for the Burroughs B6700 computer at Risoe. A short description of PLUCON2 is given. (author)

  13. Changing demographics

    International Nuclear Information System (INIS)

    Vetter, B.M.

    1991-01-01

    This paper reports on changing population demographics, poor academic preparation for and a decreasing interest in engineering among college students which indicates possible shortages ahead, particularly among chemical and petroleum engineers. The talent pool for engineering must be enlarged to include women and minority men, if we are to ensure an adequate future supply for the U.S

  14. Model to predict the radiological consequences of transportation of radioactive material through an urban environment

    International Nuclear Information System (INIS)

    Taylor, J.M.; Daniel, S.L.; DuCharme, A.R.; Finley, N.N.

    1977-01-01

    A model has been developed which predicts the radiological consequences of the transportation of radioactive material in and around urban environments. This discussion of the model includes discussion of the following general topics: health effects from radiation exposure, urban area characterization, computation of dose resulting from normal transportation, computation of dose resulting from vehicular accidents or sabotage, and preliminary results and conclusions

  15. Updates to the Demographic and Spatial Allocation Models to Produce Integrated Climate and Land Use Scenarios (ICLUS) (Final Report, Version 2)

    Science.gov (United States)

    EPA's announced the availability of the final report, Updates to the Demographic and Spatial Allocation Models to Produce Integrated Climate and Land Use Scenarios (ICLUS) (Version 2). This update furthered land change modeling by providing nationwide housing developmen...

  16. Radiological Consequences Analysis for Abnormal Condition on NPPs 1000 MWe by Using Radcon Model

    International Nuclear Information System (INIS)

    Pande Mande Udiyani; Sri Kuntjoro

    2009-01-01

    The operation of NPPs (Nuclear Power Plants) in Indonesia to anticipates rare of energy will generate various challenges, especially about NPPs safety. So installation organizer of nuclear must provide scientific argument to safety NPPs, one of them is by providing document of safety analysis. Calculation of radiological consequences after abnormal condition applies on generic PWR-1000 power reactor. Calculation is done by using program package RadCon (Radiological Consequences Model), with postulate condition is based on DBA (Design Basis Accident). Calculation of dispersion of radionuclide concentration is using PC-COSYMA as input data for RadCon. Simulation for radiological consequences analysis uses by site data sample. Analysis result shows that maximum receiving of internal - externals radiological consequence for short term and long-term below 1 km radius area is below the limit acceptably effective dose for a member of the public as a result of an accident which should not exceed 5 mSv (ICRP 1990). (author)

  17. An Investigation into the Relationship among Psychiatric, Demographic and Socio-Economic Variables with Bayesian Network Modeling

    Directory of Open Access Journals (Sweden)

    Gunal Bilek

    2018-03-01

    Full Text Available The aim of this paper is to investigate the factors influencing the Beck Depression Inventory score, the Beck Hopelessness Scale score and the Rosenberg Self-Esteem score and the relationships among the psychiatric, demographic and socio-economic variables with Bayesian network modeling. The data of 823 university students consist of 21 continuous and discrete relevant psychiatric, demographic and socio-economic variables. After the discretization of the continuous variables by two approaches, two Bayesian networks models are constructed using the b n l e a r n package in R, and the results are presented via figures and probabilities. One of the most significant results is that in the first Bayesian network model, the gender of the students influences the level of depression, with female students being more depressive. In the second model, social activity directly influences the level of depression. In each model, depression influences both the level of hopelessness and self-esteem in students; additionally, as the level of depression increases, the level of hopelessness increases, but the level of self-esteem drops.

  18. Relationships among mental health status, social context, and demographic characteristics in Taiwanese aboriginal adolescents: a structural equation model.

    Science.gov (United States)

    Yen, Cheng-Fang; Hsu, Chia-Chuang; Liu, Shu-Chun; Huang, Chi-Fen; Ko, Chih-Hung; Yen, Ju-Yu; Cheng, Chung-Ping

    2006-10-01

    The purposes of this study were to examine the relationships among mental health status, demographic characteristics, and social contexts, including family conflict and support, connectedness to school, and affiliation with peers who exhibit delinquent behavior and who use substances, among Taiwanese aboriginal adolescents. A total of 251 aboriginal junior high school students in an isolated mountainous area of southern Taiwan were recruited, and the relationships among mental health status, demographic characteristics, and social contexts among them were examined using a structural equation model (SEM). The SEM revealed that family conflict and support had direct influences on mental health status and connectedness to school. Family conflict had a direct relationship with affiliation with peers who use substances, and family conflict and support were both indirectly linked with affiliation with peers who exhibit delinquent behavior and who used substances; these were mediated by a poor mental health status. Female and older age were directly linked with a poor mental health status and were indirectly linked with a greater number of peers who exhibit delinquent behavior and who use substances via the poor mental health status. Disruptive parenting was directly linked with affiliation with peers who use substances. The authors suggest that those who devise strategies to improve aboriginal adolescents' mental health and discourage substance use should take these relationships among mental health, demographic characteristics, and social contexts into account.

  19. Environmental Consequences of Wildlife Tourism: The Use of Formalised Qualitative Models

    Directory of Open Access Journals (Sweden)

    Veselý Štěpán

    2015-09-01

    Full Text Available The paper presents a simple qualitative model of environmental consequences of wildlife tourism. Qualitative models use just three values: Positive/Increasing, Zero/Constant and Negative/Decreasing. Such quantifiers of trends are the least information intensive. Qualitative models can be useful, since models of wildlife tourism include such variables as, for example, Biodiversity (BIO, Animals’ habituation to tourists (HAB or Plant composition change (PLA that are sometimes difficult or costly to quantify. Hence, a significant fraction of available information about wildlife tourism and its consequences is not of numerical nature, for example, if HAB is increasing then BIO is decreasing. Such equationless relations are studied in this paper. The model has 10 variables and 20 equationless pairwise interrelations among them. The model is solved and 15 solutions, that is, scenarios are obtained. All qualitative states, including the first and second qualitative derivatives with respect to time, of all variables are specified for each scenario.

  20. COCO-1: model for assessing the cost of offsite consequences of accidental releases of radioactivity

    International Nuclear Information System (INIS)

    Haywood, S.M.; Robinson, C.A.; Heady, C.

    1991-09-01

    This report describes a new model, called COCO-1 (Cost Of Consequences Offsite), for assessing the offsite economic consequences of an accident involving the release of radioactive material. The costs calculated are a measure of the benefit foregone as a result of the accident, and in addition to tangible monetary costs the model attempts to include costs arising from the effect of the accident on individuals, for instance the disruption caused by the loss of homes. The approach has limitations, which are discussed, but offers a broadly applicable and robust technique for estimating the economic impact of most accidents. (author)

  1. The Population Consequences of Disturbance Model Application to North Atlantic Right Whales (Eubalaena glacialis)

    Science.gov (United States)

    2015-09-30

    physiology, and the revised approach is called PCOD (Population Consequences Of Disturbance). In North Atlantic right whales (Eubalaena glacialis...acoustic disturbance and prey variability into the PCOD model. OBJECTIVES The objectives for this study are to: 1) develop a Hierarchical...the model to assessing the effects of acoustics on the population. We have refined and applied the PCOD model developed for right whales (Schick et

  2. Projection models for health-effects assessment in populations exposed to radioactive and nonradioactive pollutants. Volume I. Introduction to the SPAHR demographic model for health risk

    International Nuclear Information System (INIS)

    Collins, J.J.; Lundy, R.T.; Grahn, D.; Ginevan, M.E.

    1982-09-01

    The Simulation Package for the Analysis of Health Risk (SPAHR) is a computer software package based upon a demographic model for health risk projections. The model extends several health risk projection models by making realistic assumptions about the population at risk, and thus represents a distinct improvement over previous models. Complete documentation for use of SPAHR is contained in this five-volume publication. The demographic model in SPAHR estimates population response to environmental toxic exposures. Latency of response, changing dose level over time, competing risks from other causes of death, and population structure can be incorporated into SPAHR to project health risks. Risks are measured by morbid years, number of deaths, and loss of life expectancy. Comparisons of estimates of excess deaths demonstrate that previous health risk projection models may have underestimated excess deaths by a factor of from 2 to 10, depending on the pollutant and the exposure scenario. The software supporting the use of the demographic model is designed to be user oriented. Complex risk projections are made by responding to a series of prompts generated by the package. The flexibility and ease of use of SPAHR make it an important contribution to existing models and software packages. The first volume presents the theory behind the SPAHR health risk projection model and several applications of the model to actual pollution episodes. The elements required for an effective health risk projection model are specified, and the models that have been used to date in health risk projections are outlined. These are compared with the demographic model, whose formulation is described in detail. Examples of the application of air pollution and radiation dose-response functions are included in order to demonstrate the estimation of future mortality and morbidity levels and the range of variation in excess deaths that occurs when populations structure is changed

  3. Projection models for health-effects assessment in populations exposed to radioactive and nonradioactive pollutants. Volume I. Introduction to the SPAHR demographic model for health risk

    Energy Technology Data Exchange (ETDEWEB)

    Collins, J.J.; Lundy, R.T.; Grahn, D.; Ginevan, M.E.

    1982-09-01

    The Simulation Package for the Analysis of Health Risk (SPAHR) is a computer software package based upon a demographic model for health risk projections. The model extends several health risk projection models by making realistic assumptions about the population at risk, and thus represents a distinct improvement over previous models. Complete documentation for use of SPAHR is contained in this five-volume publication. The demographic model in SPAHR estimates population response to environmental toxic exposures. Latency of response, changing dose level over time, competing risks from other causes of death, and population structure can be incorporated into SPAHR to project health risks. Risks are measured by morbid years, number of deaths, and loss of life expectancy. Comparisons of estimates of excess deaths demonstrate that previous health risk projection models may have underestimated excess deaths by a factor of from 2 to 10, depending on the pollutant and the exposure scenario. The software supporting the use of the demographic model is designed to be user oriented. Complex risk projections are made by responding to a series of prompts generated by the package. The flexibility and ease of use of SPAHR make it an important contribution to existing models and software packages. The first volume presents the theory behind the SPAHR health risk projection model and several applications of the model to actual pollution episodes. The elements required for an effective health risk projection model are specified, and the models that have been used to date in health risk projections are outlined. These are compared with the demographic model, whose formulation is described in detail. Examples of the application of air pollution and radiation dose-response functions are included in order to demonstrate the estimation of future mortality and morbidity levels and the range of variation in excess deaths that occurs when populations structure is changed.

  4. Improved atmospheric dispersion modelling in the new program system UFOMOD for accident consequence assessments

    International Nuclear Information System (INIS)

    Panitz, H.J.

    1988-01-01

    An essential aim of the improvements of the new program system UFOMOD for Accident Consequence Assessments (ACAs) was to substitute the straightline Gaussian plume model conventionally used in ACA models by more realistic atmospheric dispersion models. To identify improved models which can be applied in ACA codes and to quantify the implications of different concepts of dispersion modelling on the results of an ACA, probabilistic comparative calculations with different atmospheric dispersion models have been carried out. The study showed that there are trajectory models available which can be applied in ACAs and that these trajectory models provide more realistic results of ACAs than straight-line Gaussian models. This led to a completly novel concept of atmospheric dispersion modelling which distinguish between two different distance ranges of validity: the near range ( 50 km). The two ranges are assigned to respective trajectory models

  5. Demographic models reveal the shape of density dependence for a specialist insect herbivore on variable host plants.

    Science.gov (United States)

    Miller, Tom E X

    2007-07-01

    1. It is widely accepted that density-dependent processes play an important role in most natural populations. However, persistent challenges in our understanding of density-dependent population dynamics include evaluating the shape of the relationship between density and demographic rates (linear, concave, convex), and identifying extrinsic factors that can mediate this relationship. 2. I studied the population dynamics of the cactus bug Narnia pallidicornis on host plants (Opuntia imbricata) that varied naturally in relative reproductive effort (RRE, the proportion of meristems allocated to reproduction), an important plant quality trait. I manipulated per-plant cactus bug densities, quantified subsequent dynamics, and fit stage-structured models to the experimental data to ask if and how density influences demographic parameters. 3. In the field experiment, I found that populations with variable starting densities quickly converged upon similar growth trajectories. In the model-fitting analyses, the data strongly supported a model that defined the juvenile cactus bug retention parameter (joint probability of surviving and not dispersing) as a nonlinear decreasing function of density. The estimated shape of this relationship shifted from concave to convex with increasing host-plant RRE. 4. The results demonstrate that host-plant traits are critical sources of variation in the strength and shape of density dependence in insects, and highlight the utility of integrated experimental-theoretical approaches for identifying processes underlying patterns of change in natural populations.

  6. Modelling the consequences of increasing bioenergy demand on land and feed use

    NARCIS (Netherlands)

    Banse, M.A.H.; Tabeau, A.A.; Meijl, van H.; Woltjer, G.B.

    2010-01-01

    The aim of this paper is to show the consequences of a model extension towards the presentation of by-product in the production of biofuels. By-products can be used as a substitute for feed grain use in livestock production. A boost in biofuel production will also show a strong increase in the

  7. Developments in modelling the economic impact of Off-site accident consequences

    International Nuclear Information System (INIS)

    Haywood, S.M.; Robinson, C.A.; Faude, D.

    1991-01-01

    Models for assessing the economic consequences of accidental releases of radioactivity have application both in accident consequence codes and in decision aiding computer systems for use in emergency response. Such models may be applied in emergency planning, and studies in connection with the siting, design and licensing of nuclear facilities. Several models for predicting economic impact have been developed, in Europe and the US, and these are reviewed. A new model, called COCO-1 (Cost of Consequences Off-site), has been developed under the CEC MARIA programme and the features of the model are summarised. The costs calculated are a measure of the benefit foregone as a result of the accident, and in addition to tangible monetary costs the model attempts to include costs arising from the effect of the accident on individuals, for instance the disruption caused by the loss of homes. COCO-1 includes the cost of countermeasures, namely evacuation, relocation, sheltering, food restrictions and decontamination, and also the cost of health effects in the exposed population. The primary quantity used in COCO-1 to measure the economic value of land subject to restrictions on usage is Gross Domestic Product (GDP). Examples of default data included in the model are presented, as are the results of an illustrative application. The limitations of COCO-1 are discussed, and areas where further data are needed are identified

  8. Protecting the larger fish: an ecological, economical and evolutionary analysis using a demographic model

    DEFF Research Database (Denmark)

    Verdiell, Nuria Calduch

    . Recently, there is increasing evidence that this size-selective fishing reduces the chances of maintaining populations at levels sufficient to produce maximum sustainable yields, the chances of recovery/rebuilding populations that have been depleted/collapsed and may causes rapid evolutionary changes...... and the consequent changes in yield. We attempt to evaluate the capability of the larger fish to mitigate the evolutionary change on life-history traits caused by fishing, while also maintaining a sustainable annual yield. This is achieved by calculating the expected selection response on three life-history traits......Many marine fish stocks are reported as overfished on a global scale. This overfishing not only removes fish biomass, but also causes dramatic changes in the age and size structure of fish stocks. In particular, targeting of the larger individuals truncates the age and size structure of stocks...

  9. The usefulness of time-dependent reactor accident consequence modelling for emergency response planning

    International Nuclear Information System (INIS)

    Paretzke, H.G.; Jacob, P.; Mueller, H.; Proehl, G.

    1989-01-01

    After major releases of radionuclides into the atmosphere fast reaction of authorities will be necessary to inform the public of potential consequences and to consider and optimize mitigating actions. These activities require availability of well designed computer models, adequate and fast measurements and prior training of responsible persons. The quantitative assessment models should be capable of taking into account of actual atmospheric dispersion conditions, actual deposition situation (dry, rain, snow, fog), seasonal status of the agriculture, food processing and distribution pathways, etc. In this paper the usefulness of such models will be discussed, their limitations, the relative importance of exposure pathways and a selection of important methods to decrease the activity in food products after an accident. Real-time reactor accident consequence models should be considered as a condition sine qua non for responsible use of nuclear power for electricity production

  10. Modelling the Antecedent and Consequence of Consumer Perceived Deception in Loan Services

    OpenAIRE

    Mbawuni Joseph; Simon Gyasi Nimako

    2015-01-01

    This paper assesses the antecedent and consequence of consumer perceived deception (CPD) on consumer trust, satisfaction, attitude recommendation and intentions to acquire future loans from financial service providers. The proposed research model was tested using data from a survey of 371 loan customers of leading financial service providers in Ghana. Data were analysed using SmartPLS 2.0 for Partial Least Squares Structural Equation Modelling. The results show high information quality could ...

  11. Consequences, norms, and generalized inaction in moral dilemmas: The CNI model of moral decision-making.

    Science.gov (United States)

    Gawronski, Bertram; Armstrong, Joel; Conway, Paul; Friesdorf, Rebecca; Hütter, Mandy

    2017-09-01

    Research on moral dilemma judgments has been fundamentally shaped by the distinction between utilitarianism and deontology. According to the principle of utilitarianism, the moral status of behavioral options depends on their consequences; the principle of deontology states that the moral status of behavioral options depends on their consistency with moral norms. To identify the processes underlying utilitarian and deontological judgments, researchers have investigated responses to moral dilemmas that pit one principle against the other (e.g., trolley problem). However, the conceptual meaning of responses in this paradigm is ambiguous, because the central aspects of utilitarianism and deontology-consequences and norms-are not manipulated. We illustrate how this shortcoming undermines theoretical interpretations of empirical findings and describe an alternative approach that resolves the ambiguities of the traditional paradigm. Expanding on this approach, we present a multinomial model that allows researchers to quantify sensitivity to consequences (C), sensitivity to moral norms (N), and general preference for inaction versus action irrespective of consequences and norms (I) in responses to moral dilemmas. We present 8 studies that used this model to investigate the effects of gender, cognitive load, question framing, and psychopathy on moral dilemma judgments. The findings obtained with the proposed CNI model offer more nuanced insights into the determinants of moral dilemma judgments, calling for a reassessment of dominant theoretical assumptions. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  12. Demonstration uncertainty/sensitivity analysis using the health and economic consequence model CRAC2

    International Nuclear Information System (INIS)

    Alpert, D.J.; Iman, R.L.; Johnson, J.D.; Helton, J.C.

    1985-01-01

    This paper summarizes a demonstration uncertainty/sensitivity analysis performed on the reactor accident consequence model CRAC2. The study was performed with uncertainty/sensitivity analysis techniques compiled as part of the MELCOR program. The principal objectives of the study were: 1) to demonstrate the use of the uncertainty/sensitivity analysis techniques on a health and economic consequence model, 2) to test the computer models which implement the techniques, 3) to identify possible difficulties in performing such an analysis, and 4) to explore alternative means of analyzing, displaying, and describing the results. Demonstration of the applicability of the techniques was the motivation for performing this study; thus, the results should not be taken as a definitive uncertainty analysis of health and economic consequences. Nevertheless, significant insights on health and economic consequence analysis can be drawn from the results of this type of study. Latin hypercube sampling (LHS), a modified Monte Carlo technique, was used in this study. LHS generates a multivariate input structure in which all the variables of interest are varied simultaneously and desired correlations between variables are preserved. LHS has been shown to produce estimates of output distribution functions that are comparable with results of larger random samples

  13. Dynamic N -occupancy models: estimating demographic rates and local abundance from detection-nondetection data

    Science.gov (United States)

    Sam Rossman; Charles B. Yackulic; Sarah P. Saunders; Janice Reid; Ray Davis; Elise F. Zipkin

    2016-01-01

    Occupancy modeling is a widely used analytical technique for assessing species distributions and range dynamics. However, occupancy analyses frequently ignore variation in abundance of occupied sites, even though site abundances affect many of the parameters being estimated (e.g., extinction, colonization, detection probability). We introduce a new model (“dynamic

  14. Measurement and Exploration of Individual Beliefs About the Consequences of Building Information Modelling Use

    DEFF Research Database (Denmark)

    Davies, Richard; Harty, Chris

    2013-01-01

    the consequences of BIM use were broadly favourable although there is a need for more data for comparisons. The structure of the responses showed that expectations that BIM would enhance job performance were strongly related to expectations that BIM use was compatible with preferred and existing ways of working...... of the consequences of ICT use predict subsequent usage. We describe the development of scales to measure beliefs about the consequences of building information modelling (BIM) and their use in a survey of employees of a large construction contracting organization in the United Kingdom. Scales for performance...... expectancy, effort expectancy, social influence, facilitating conditions, compatibility, and attitude toward using technology were adapted from existing measures. In an analysis of responses from 762 construction employees the scales showed acceptable measurement properties. Expectations about...

  15. Developing logistic regression models using purchase attributes and demographics to predict the probability of purchases of regular and specialty eggs.

    Science.gov (United States)

    Bejaei, M; Wiseman, K; Cheng, K M

    2015-01-01

    Consumers' interest in specialty eggs appears to be growing in Europe and North America. The objective of this research was to develop logistic regression models that utilise purchaser attributes and demographics to predict the probability of a consumer purchasing a specific type of table egg including regular (white and brown), non-caged (free-run, free-range and organic) or nutrient-enhanced eggs. These purchase prediction models, together with the purchasers' attributes, can be used to assess market opportunities of different egg types specifically in British Columbia (BC). An online survey was used to gather data for the models. A total of 702 completed questionnaires were submitted by BC residents. Selected independent variables included in the logistic regression to develop models for different egg types to predict the probability of a consumer purchasing a specific type of table egg. The variables used in the model accounted for 54% and 49% of variances in the purchase of regular and non-caged eggs, respectively. Research results indicate that consumers of different egg types exhibit a set of unique and statistically significant characteristics and/or demographics. For example, consumers of regular eggs were less educated, older, price sensitive, major chain store buyers, and store flyer users, and had lower awareness about different types of eggs and less concern regarding animal welfare issues. However, most of the non-caged egg consumers were less concerned about price, had higher awareness about different types of table eggs, purchased their eggs from local/organic grocery stores, farm gates or farmers markets, and they were more concerned about care and feeding of hens compared to consumers of other eggs types.

  16. Model description. NUDOS: A computer program for assessing the consequences of airborne releases of radionuclides

    International Nuclear Information System (INIS)

    Poley, A.D.

    1996-02-01

    NUDOS is a computer program that can be used to evaluate the consequences of airborne releases of radioactive material. The consequences which can be evaluated are individual dose and associated radiological risk, collective dose and the contamination of land. The code is capable of dealing with both continuous (routine) and accidental releases. For accidental releases both deterministic and probabilistic calculations can be performed, and the impact and effectiveness of emergency actions can be evaluated. This report contains a description of the models contained in NUDOS92 and the recommended values for the input parameters of these models. Additionally, a short overview is given of the future model improvement planned for the next NUDOS-version. (orig.)

  17. German offsite accident consequence model for nuclear facilities: further development and application

    International Nuclear Information System (INIS)

    Bayer, A.

    1985-01-01

    The German Offsite Accident Consequence Model - first applied in the German Risk Study for nuclear power plants with light water reactors - has been further developed with the improvement of several important submodels in the areas of atmospheric dispersion, shielding effects of houses, and the foodchains. To aid interpretation, the presentation of results has been extended with special emphasis on the presentation of the loss of life expectancy. The accident consequence model has been further developed for application to risk assessments for other nuclear facilities, e.g., the liquid metal fast breeder reactor (SNR-300) and the high temperature gas cooled reactor. Moreover the model have been further developed in the area of optimal countermeasure strategies (sheltering, evacuation, etc.) in the case of the Central European conditions. Preliminary considerations has been performed in connection with safety goals on the basis of doses

  18. Soils apart from equilibrium – consequences for soil carbon balance modelling

    Directory of Open Access Journals (Sweden)

    T. Wutzler

    2007-01-01

    Full Text Available Many projections of the soil carbon sink or source are based on kinetically defined carbon pool models. Para-meters of these models are often determined in a way that the steady state of the model matches observed carbon stocks. The underlying simplifying assumption is that observed carbon stocks are near equilibrium. This assumption is challenged by observations of very old soils that do still accumulate carbon. In this modelling study we explored the consequences of the case where soils are apart from equilibrium. Calculation of equilibrium states of soils that are currently accumulating small amounts of carbon were performed using the Yasso model. It was found that already very small current accumulation rates cause big changes in theoretical equilibrium stocks, which can virtually approach infinity. We conclude that soils that have been disturbed several centuries ago are not in equilibrium but in a transient state because of the slowly ongoing accumulation of the slowest pool. A first consequence is that model calibrations to current carbon stocks that assume equilibrium state, overestimate the decay rate of the slowest pool. A second consequence is that spin-up runs (simulations until equilibrium overestimate stocks of recently disturbed sites. In order to account for these consequences, we propose a transient correction. This correction prescribes a lower decay rate of the slowest pool and accounts for disturbances in the past by decreasing the spin-up-run predicted stocks to match an independent estimate of current soil carbon stocks. Application of this transient correction at a Central European beech forest site with a typical disturbance history resulted in an additional carbon fixation of 5.7±1.5 tC/ha within 100 years. Carbon storage capacity of disturbed forest soils is potentially much higher than currently assumed. Simulations that do not adequately account for the transient state of soil carbon stocks neglect a considerable

  19. Consequence Based Design. An approach for integrating computational collaborative models (Integrated Dynamic Models) in the building design phase

    DEFF Research Database (Denmark)

    Negendahl, Kristoffer

    relies on various advancements in the area of integrated dynamic models. It also relies on the application and test of the approach in practice to evaluate the Consequence based design and the use of integrated dynamic models. As a result, the Consequence based design approach has been applied in five...... and define new ways to implement integrated dynamic models for the following project. In parallel, seven different developments of new methods, tools and algorithms have been performed to support the application of the approach. The developments concern: Decision diagrams – to clarify goals and the ability...... affect the design process and collaboration between building designers and simulationists. Within the limits of applying the approach of Consequence based design to five case studies, followed by documentation based on interviews, surveys and project related documentations derived from internal reports...

  20. Modelling techniques for predicting the long term consequences of radiation on natural aquatic populations

    International Nuclear Information System (INIS)

    Wallis, I.G.

    1978-01-01

    The purpose of this working paper is to describe modelling techniques for predicting the long term consequences of radiation on natural aquatic populations. Ideally, it would be possible to use aquatic population models: (1) to predict changes in the health and well-being of all aquatic populations as a result of changing the composition, amount and location of radionuclide discharges; (2) to compare the effects of steady, fluctuating and accidental releases of radionuclides; and (3) to evaluate the combined impact of the discharge of radionuclides and other wastes, and natural environmental stresses on aquatic populations. At the onset it should be stated that there is no existing model which can achieve this ideal performance. However, modelling skills and techniques are available to develop useful aquatic population models. This paper discusses the considerations involved in developing these models and briefly describes the various types of population models which have been developed to date

  1. Towards thresholds of disaster management performance under demographic change: exploring functional relationships using agent-based modeling

    Directory of Open Access Journals (Sweden)

    G. Dressler

    2016-10-01

    Full Text Available Effective disaster management is a core feature for the protection of communities against natural disasters such as floods. Disaster management organizations (DMOs are expected to contribute to ensuring this protection. However, what happens when their resources to cope with a flood are at stake or the intensity and frequency of the event exceeds their capacities? Many cities in the Free State of Saxony, Germany, were strongly hit by several floods in the last years and are additionally challenged by demographic change, with an ageing society and out-migration leading to population shrinkage in many parts of Saxony. Disaster management, which is mostly volunteer-based in Germany, is particularly affected by this change, leading to a loss of members. We propose an agent-based simulation model that acts as a "virtual lab" to explore the impact of various changes on disaster management performance. Using different scenarios we examine the impact of changes in personal resources of DMOs, their access to operation relevant information, flood characteristics as well as differences between geographic regions. A loss of DMOs and associated manpower caused by demographic change has the most profound impact on the performance. Especially in rural, upstream regions population decline in combination with very short lead times can put disaster management performance at risk.

  2. Analysis of uncertainties caused by the atmospheric dispersion model in accident consequence assessments with UFOMOD

    International Nuclear Information System (INIS)

    Fischer, F.; Ehrhardt, J.

    1988-06-01

    Various techniques available for uncertainty analysis of large computer models are applied, described and selected as most appropriate for analyzing the uncertainty in the predictions of accident consequence assessments. The investigation refers to the atmospheric dispersion and deposition submodel (straight-line Gaussian plume model) of UFOMOD, whose most important input variables and parameters are linked with probability distributions derived from expert judgement. Uncertainty bands show how much variability exists, sensitivity measures determine what causes this variability in consequences. Results are presented as confidence bounds of complementary cumulative frequency distributions (CCFDs) of activity concentrations, organ doses and health effects, partially as a function of distance from the site. In addition the ranked influence of the uncertain parameters on the different consequence types is shown. For the estimation of confidence bounds it was sufficient to choose a model parameter sample size of n (n=59) equal to 1.5 times the number of uncertain model parameters. Different samples or an increase of sample size did not change the 5%-95% - confidence bands. To get statistically stable results of the sensitivity analysis, larger sample sizes are needed (n=100, 200). Random or Latin-hypercube sampling schemes as tools for uncertainty and sensitivity analyses led to comparable results. (orig.) [de

  3. Combining dendrochronology and matrix modelling in demographic studies: An evaluation for Juniperus procera in Ethiopia

    NARCIS (Netherlands)

    Couralet, C.; Sass, U.G.W.; Sterck, F.J.; Zuidema, P.A.

    2005-01-01

    Tree demography was analysed by applying dendrochronological techniques and matrix modelling on a static data set of Juniperus procera populations of Ethiopian dry highland forests. Six permanent sample plots were established for an inventory of diameters and 11 stem discs were collected for

  4. Assessment of Prevalence of Persons with Down Syndrome: A Theory-Based Demographic Model

    Science.gov (United States)

    de Graaf, Gert; Vis, Jeroen C.; Haveman, Meindert; van Hove, Geert; de Graaf, Erik A. B.; Tijssen, Jan G. P.; Mulder, Barbara J. M.

    2011-01-01

    Background: The Netherlands are lacking reliable empirical data in relation to the development of birth and population prevalence of Down syndrome. For the UK and Ireland there are more historical empirical data available. A theory-based model is developed for predicting Down syndrome prevalence in the Netherlands from the 1950s onwards. It is…

  5. Cost-effectiveness analysis of countermeasures using accident consequence assessment models

    International Nuclear Information System (INIS)

    Alonso, A.; Gallego, E.

    1987-01-01

    In the event of a large release of radionuclides from a nuclear power plant, protective actions for the population potentially affected must be implemented. Cost-effectiveness analysis will be useful to define the countermeasures and the criteria needed to implement them. This paper shows the application of Accident Consequence Assessment (ACA) models to cost-effectiveness analysis of emergency and long-term countermeasures, making use of the different relationships between dose, contamination levels, affected areas and population distribution, included in such a model. The procedure is illustrated with the new Melcor Accident Consequence Code System (MACCS 1.3), developed at Sandia National Laboratories (USA), for a fixed accident scenario. Different alternative actions are evaluated with regard to their radiological and economical impact, searching for an 'optimum' strategy. (author)

  6. Statistical surrogate models for prediction of high-consequence climate change.

    Energy Technology Data Exchange (ETDEWEB)

    Constantine, Paul; Field, Richard V., Jr.; Boslough, Mark Bruce Elrick

    2011-09-01

    In safety engineering, performance metrics are defined using probabilistic risk assessments focused on the low-probability, high-consequence tail of the distribution of possible events, as opposed to best estimates based on central tendencies. We frame the climate change problem and its associated risks in a similar manner. To properly explore the tails of the distribution requires extensive sampling, which is not possible with existing coupled atmospheric models due to the high computational cost of each simulation. We therefore propose the use of specialized statistical surrogate models (SSMs) for the purpose of exploring the probability law of various climate variables of interest. A SSM is different than a deterministic surrogate model in that it represents each climate variable of interest as a space/time random field. The SSM can be calibrated to available spatial and temporal data from existing climate databases, e.g., the Program for Climate Model Diagnosis and Intercomparison (PCMDI), or to a collection of outputs from a General Circulation Model (GCM), e.g., the Community Earth System Model (CESM) and its predecessors. Because of its reduced size and complexity, the realization of a large number of independent model outputs from a SSM becomes computationally straightforward, so that quantifying the risk associated with low-probability, high-consequence climate events becomes feasible. A Bayesian framework is developed to provide quantitative measures of confidence, via Bayesian credible intervals, in the use of the proposed approach to assess these risks.

  7. Formation of decontamination cost calculation model for severe accident consequence assessment

    International Nuclear Information System (INIS)

    Silva, Kampanart; Promping, Jiraporn; Okamoto, Koji; Ishiwatari, Yuki

    2014-01-01

    In previous studies, the authors developed an index “cost per severe accident” to perform a severe accident consequence assessment that can cover various kinds of accident consequences, namely health effects, economic, social and environmental impacts. Though decontamination cost was identified as a major component, it was taken into account using simple and conservative assumptions, which make it difficult to have further discussions. The decontamination cost calculation model was therefore reconsidered. 99 parameters were selected to take into account all decontamination-related issues, and the decontamination cost calculation model was formed. The distributions of all parameters were determined. A sensitivity analysis using the Morris method was performed in order to identify important parameters that have large influence on the cost per severe accident and large extent of interactions with other parameters. We identified 25 important parameters, and fixed most negligible parameters to the median of their distributions to form a simplified decontamination cost calculation model. Calculations of cost per severe accident with the full model (all parameters distributed), and with the simplified model were performed and compared. The differences of the cost per severe accident and its components were not significant, which ensure the validity of the simplified model. The simplified model is used to perform a full scope calculation of the cost per severe accident and compared with the previous study. The decontamination cost increased its importance significantly. (author)

  8. [Mobbing: a meta-analysis and integrative model of its antecedents and consequences].

    Science.gov (United States)

    Topa Cantisano, Gabriela; Depolo, Marco; Morales Domínguez, J Francisco

    2007-02-01

    Although mobbing has been extensively studied, empirical research has not led to firm conclusions regarding its antecedents and consequences, both at personal and organizational levels. An extensive literature search yielded 86 empirical studies with 93 samples. The matrix correlation obtained through meta-analytic techniques was used to test a structural equation model. Results supported hypotheses regarding organizational environmental factors as main predictors of mobbing.

  9. Synthesis of the models used in France for the evaluation of the consequences of accident

    International Nuclear Information System (INIS)

    Crabol, B.

    1992-01-01

    In order to evaluate the consequences of an atmospheric release in case of an accident on a nuclear installation, different predictive models have been developed by the organizations involved in the management of the crisis. These models are of different numerical complexity: precalculated graphs, gaussian puff models or 3D models. The harmonization of these models, the definition of their use, notably in the first phases of the accident (predictive and real-time phases) have been discussed in a working group including representants of the utility, the safety authorities and the Meteorological Office. The reflexions of the group, the models already operational, those still under discussion and their use in the different technical crisis centers are presented

  10. A model for radiological consequences of nuclear power plant operational atmospheric releases

    International Nuclear Information System (INIS)

    Kocar, Cemil; Soekmen, Cemal Niyazi

    2009-01-01

    A dynamic dose and risk assessment model is developed to estimate radiological consequences of atmospheric emissions from nuclear power plants. Internal exposure via inhalation and ingestion, external exposure from clouds and radioactivity deposited on the ground are included in the model. The model allows to simulate interregional moves of people and multi-location food supply in the computational domain. Any long-range atmospheric dispersion model which yields radionuclide concentrations in air and on the ground at predetermined time intervals can easily be integrated into the model. The software developed is validated against radionuclide concentrations measured in different environmental media and dose values estimated after the Chernobyl accident. Results obtained using the model compare well with dose estimates and activities measured in foodstuffs and feedstuffs

  11. Hidden consequences of political efficacy: Testing an efficacy-apathy model of political mobilization.

    Science.gov (United States)

    Osborne, Danny; Yogeeswaran, Kumar; Sibley, Chris G

    2015-10-01

    Political efficacy-the belief that one can influence politics-is a key predictor of people's involvement in social movements. Political institutions that are open to change should, however, be seen as just. Thus, political efficacy may ironically undermine minority group members' support for collective action by simultaneously increasing their belief in the fairness of the system. The current study aims to examine this possibility in a national sample of Māori-New Zealand's indigenous minority population. Participants (N = 399) were Māori (Mage = 44.22; SD = 13.30) women (n = 272) and men (n = 115; unreported = 12) who completed a survey assessing their levels of (a) political efficacy, (b) system justification, and (c) support for the political mobilization of their group, as well as relevant demographic covariates. Consistent with past research, political efficacy had a positive direct effect on participants' support for the political mobilization of Māori. Nevertheless, political efficacy also had a negative indirect effect on political mobilization support via increases in system justification. These results held after controlling for participants' ethnic identification, self-efficacy, and conservatism. Our findings uncover a hidden consequence of political efficacy and show that, while believing that the political system is receptive to change predicts political mobilization, it can also undermine minorities' support for the mobilization of their group. Thus, our results uncover a previously unknown process that maintains inequality between ethnic minority and majority group members. (c) 2015 APA, all rights reserved).

  12. Comparison of INTERA and WISAP consequence model application. Assessment of effectiveness of geologic isolation systems

    International Nuclear Information System (INIS)

    Cole, C.R.; Bond, F.W.

    1980-01-01

    The Waste Isolation Safety Assessment Program (WISAP) is being conducted to develop, for the Office of Nuclear Waste Isolation (ONWI), the methodology necessary to perform long-term safety assessments of deep geologic repositories. The Waste Isolation Pilot Plant (WIPP) program is developing a nuclear waste storage facility and is performing assessments of that site. WISAP and WIPP have similar, though independent, methodologies for assessing the consequences of a repository breach subsequent to closure. Intera Environmental Consultants are under contract to Sandia Laboratories to conduct the hydrologic and transport modeling for the WIPP Site Release Consequence Analysis (WIPP EIS/ER 1978). To provide a mutual benchmark check of the radionuclide and ground-water transport models of these two programs, ONWI has requested WISAP to perform a release consequence analysis based on the WIPP site, utilizing the same data and conceptual model which the WIPP program used for its environmental assessments. Therefore, only a portion of the WISAP methodology was used; specifically, only WISAP geotransport models were exercised. The other important parts of WISAP assessment methodology were not used, so that WISAP did not develop the scenario nor did WISAP interpret the field data to develop the conceptual model of the geohydrology of the WIPP site. The results of the comparative assessment are presented. Although the different models required slightly different input parameters, the results of the hydrologic simulations show a very close correspondence between the WISAP and WIPP predictions. This was as expected, since the various hydrologic codes available essentially utilize and solve the same basic flow equations. In addition, this report presents the results of the WISAP radionuclide transport model simulations. These results will provide the basis for comparison with WIPP results when these become available

  13. Demographic factors and cancer mortality. A mathematical model for cancer mortality in Denmark 1943-78

    DEFF Research Database (Denmark)

    Juel, K

    1983-01-01

    young adult life into old age. One-year age-specific mortality rates between 30 and 79 years of age were computed for 14 different cancer sites among both males and females, in five ten-year birth cohorts and for the capital and provinces. The number of deaths at a particular age were found to follow...... a Poisson distribution and the mortality rate could be expressed by the function lx = bxk, where lx is the mortality rate at age x, and b and k are parameters to be estimated. With this model a straight line is obtained, when mortality and age are plotted on a double logarithmic scale. The maximum...

  14. Using dynamic N-mixture models to test cavity limitation on northern flying squirrel demographic parameters using experimental nest box supplementation.

    Science.gov (United States)

    Priol, Pauline; Mazerolle, Marc J; Imbeau, Louis; Drapeau, Pierre; Trudeau, Caroline; Ramière, Jessica

    2014-06-01

    Dynamic N-mixture models have been recently developed to estimate demographic parameters of unmarked individuals while accounting for imperfect detection. We propose an application of the Dail and Madsen (2011: Biometrics, 67, 577-587) dynamic N-mixture model in a manipulative experiment using a before-after control-impact design (BACI). Specifically, we tested the hypothesis of cavity limitation of a cavity specialist species, the northern flying squirrel, using nest box supplementation on half of 56 trapping sites. Our main purpose was to evaluate the impact of an increase in cavity availability on flying squirrel population dynamics in deciduous stands in northwestern Québec with the dynamic N-mixture model. We compared abundance estimates from this recent approach with those from classic capture-mark-recapture models and generalized linear models. We compared apparent survival estimates with those from Cormack-Jolly-Seber (CJS) models. Average recruitment rate was 6 individuals per site after 4 years. Nevertheless, we found no effect of cavity supplementation on apparent survival and recruitment rates of flying squirrels. Contrary to our expectations, initial abundance was not affected by conifer basal area (food availability) and was negatively affected by snag basal area (cavity availability). Northern flying squirrel population dynamics are not influenced by cavity availability at our deciduous sites. Consequently, we suggest that this species should not be considered an indicator of old forest attributes in our study area, especially in view of apparent wide population fluctuations across years. Abundance estimates from N-mixture models were similar to those from capture-mark-recapture models, although the latter had greater precision. Generalized linear mixed models produced lower abundance estimates, but revealed the same relationship between abundance and snag basal area. Apparent survival estimates from N-mixture models were higher and less precise

  15. The design and application of a radiological consequence model for tropical and subtropical regions

    International Nuclear Information System (INIS)

    Domel, R.U.; Harris, F.F.; Crawford, J.

    1998-01-01

    The post Chernobyl era has seen the development of a plethora of radiological consequence models. The information used in these models pertains mostly to temperate and cold climate data, with these data mostly being hard-wired into the body of the model. At the Australian Nuclear Science and Technology Organisation (ANSTO), a model is being developed with a user-friendly interface which will assess the radiological consequences, after an incident, in tropical and sub-tropical climates. The model combines specific regional data (South East Asia) with transfer parameters (soil to plant, plant to animal) obtained for tropical and sub-tropical regions. Flexibility has been incorporated into the the design of the model to allow application in other regions. Where the relevant data are not available, default temperate data are used whilst specific research will be initiated to determine the information required. A Geographic Information System (GIS) is used for the display of input and output data allowing quick access to not only the results but also to the underlying assumptions

  16. Health effects models for off-site radiological consequence analysis on nuclear reactor accidents (II)

    Energy Technology Data Exchange (ETDEWEB)

    Homma, Toshimitsu [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Takahashi, Tomoyuki [Kyoto Univ., Kumatori, Osaka (Japan). Research Reactor Inst; Yonehara, Hidenori [National Inst. of Radiological Sciences, Chiba (Japan)] [eds.

    2000-12-01

    This report is a revision of JAERI-M 91-005, 'Health Effects Models for Off-Site Radiological Consequence Analysis of Nuclear Reactor Accidents'. This revision provides a review of two revisions of NUREG/CR-4214 reports by the U.S. Nuclear Regulatory Commission which is the basis of the JAERI health effects models and other several recent reports that may impact the health effects models by international organizations. The major changes to the first version of the JAERI health effects models and the recommended parameters in this report are for late somatic effects. These changes reflect recent changes in cancer risk factors that have come from longer followup and revised dosimetry in major studies on the Japanese A-bomb survivors. This report also provides suggestions about future revisions of computational aspects on health effects models. (author)

  17. Health effects models for off-site radiological consequence analysis on nuclear reactor accidents (II)

    International Nuclear Information System (INIS)

    Homma, Toshimitsu

    2000-12-01

    This report is a revision of JAERI-M 91-005, 'Health Effects Models for Off-Site Radiological Consequence Analysis of Nuclear Reactor Accidents'. This revision provides a review of two revisions of NUREG/CR-4214 reports by the U.S. Nuclear Regulatory Commission which is the basis of the JAERI health effects models and other several recent reports that may impact the health effects models by international organizations. The major changes to the first version of the JAERI health effects models and the recommended parameters in this report are for late somatic effects. These changes reflect recent changes in cancer risk factors that have come from longer followup and revised dosimetry in major studies on the Japanese A-bomb survivors. This report also provides suggestions about future revisions of computational aspects on health effects models. (author)

  18. Comparative study on demographic-economic model-building for three selected countries of the ESCAP region.

    Science.gov (United States)

    1980-01-01

    The research project involves building models for 3 selected ESCAP countries, Indonesia, Japan, and the Republic of Korea, which are at different stages of demographic transition. This project involves country level research workd esigned, implemented, and monitored with the assistance of ESCAP. Accordingly the 1st Study Directors' Meeting was held in Bangkok during November 16-30, 1979 in a series of informal interactive working sessions for Study Directors, modelling experts, and resource persons. The participants were Study Directors from the above mentioned countries and a few experts from Malaysia, Thailand, ILO, UNRISD, and IBRD. The main objective of the meeting was to help finance the basic model framework in order that National Study Directors will be able to commence their modelling work after the Meeting. As evidenced by the Report of the 1st Study Directors' Meeting, this objective was achieved. Following this meeting, the 3 case studies are being simultaneously undertaken in countries by national study teams with technical support provided by ESCAP.

  19. Conditions and consequences of medical futility--from a literature review to a clinical model.

    Science.gov (United States)

    Löfmark, R; Nilstun, T

    2002-04-01

    To present an analysis of "futility" that is useful in the clinical setting. Literature review. According to Medline more than 750 articles have been published about medical futility. Three criteria (language, time period, and the authors expressed their own opinions) singled out 43 of them. The authors' opinions about futility were analysed using the scheme: "If certain conditions are satisfied, then a particular measure is futile" and "If a particular measure is futile, then certain moral consequences are implied". Regarding conditions, most authors stated that judgments about futility should be made by physicians. The measure was usually some kind of medical treatment, and the goals related to quality of life, physiological improvement, or prolongation of life. The probability of success in reaching the goal was in most cases described in semiquantitative terms. Regarding consequences, the authors stated that health care professionals may (sometimes ought or should) withhold or withdraw a futile measure, most often after a dialogue with the patient (29 articles), but sometimes without informing the patient (nine articles), or with one-way information (four articles). Over time more and more articles recommend that the patient should be involved in joint decision making. Based on this literature review a clinical model was developed. The model, requiring that conditions and consequences should be made explicit, may, in "futility situations", facilitate both the collection of the necessary information and make the moral implications visible. It also makes communication about measures considered to be futile possible without using such ambiguous terms as "futile".

  20. Chronic subordinate colony housing paradigm: A mouse model to characterize the consequences of insufficient glucocorticoid signalling

    Directory of Open Access Journals (Sweden)

    Dominik eLanggartner

    2015-02-01

    Full Text Available Chronic, in particular chronic psychosocial, stress is a burden of modern societies and known to be a risk factor for numerous somatic and affective disorders (in detail referenced below. However, based on the limited existence of appropriate, and clinically-relevant, animal models for studying the effects of chronic stress, the detailed behavioural, physiological, neuronal, and immunological mechanisms linking stress and such disorders are insufficiently understood. To date, most chronic stress studies in animals employ intermittent exposure to the same (homotypic or to different (heterotypic stressors of varying duration and intensity. Such models are only of limited value, since they do not adequately reflect the chronic, and continuous, situation that humans typically experience. Furthermore, application of different physical or psychological stimuli renders comparisons to the mainly psychosocial stressors faced by humans, as well as between the different stress studies almost impossible. In contrast, rodent models of chronic psychosocial stress represent situations more akin to those faced by humans and consequently seem to hold more clinical relevance. Our laboratory has developed a model in which mice are exposed to social stress for 19 continuous days, namely the chronic subordinate colony housing (CSC paradigm, which bridges this gap. The main aim of the current review article is to provide a detailed summary of the behavioural, physiological, neuronal and immunological consequences of the CSC paradigm, and wherever possible relate the findings to other stress models and to those from human studies.

  1. Continuous spatial modelling to analyse planning and economic consequences of offshore wind energy

    International Nuclear Information System (INIS)

    Moeller, Bernd

    2011-01-01

    Offshore wind resources appear abundant, but technological, economic and planning issues significantly reduce the theoretical potential. While massive investments are anticipated and planners and developers are scouting for viable locations and consider risk and impact, few studies simultaneously address potentials and costs together with the consequences of proposed planning in an analytical and continuous manner and for larger areas at once. Consequences may be investments short of efficiency and equity, and failed planning routines. A spatial resource economic model for the Danish offshore waters is presented, used to analyse area constraints, technological risks, priorities for development and opportunity costs of maintaining competing area uses. The SCREAM-offshore wind model (Spatially Continuous Resource Economic Analysis Model) uses raster-based geographical information systems (GIS) and considers numerous geographical factors, technology and cost data as well as planning information. Novel elements are weighted visibility analysis and geographically recorded shipping movements as variable constraints. A number of scenarios have been described, which include restrictions of using offshore areas, as well as alternative uses such as conservation and tourism. The results comprise maps, tables and cost-supply curves for further resource economic assessment and policy analysis. A discussion of parameter variations exposes uncertainties of technology development, environmental protection as well as competing area uses and illustrates how such models might assist in ameliorating public planning, while procuring decision bases for the political process. The method can be adapted to different research questions, and is largely applicable in other parts of the world. - Research Highlights: → A model for the spatially continuous evaluation of offshore wind resources. → Assessment of spatial constraints, costs and resources for each location. → Planning tool for

  2. Long-term consequences of non-intentional flows of substances: Modelling non-intentional flows of lead in the Dutch economic system and evaluating their environmental consequences

    International Nuclear Information System (INIS)

    Elshkaki, Ayman; Voet, Ester van der; Holderbeke, Mirja van; Timmermans, Veerle

    2009-01-01

    Substances may enter the economy and the environment through both intentional and non-intentional flows. These non-intentional flows, including the occurrence of substances as pollutants in mixed primary resources (metal ores, phosphate ores and fossil fuels) and their presence in re-used waste streams from intentional use may have environmental and economic consequences in terms of pollution and resource availability. On the one hand, these non-intentional flows may cause pollution problems. On the other hand, these flows have the potential to be a secondary source of substances. This article aims to quantify and model the non-intentional flows of lead, to evaluate their long-term environmental consequences, and compare these consequences to those of the intentional flows of lead. To meet this goal, the model combines all the sources of non-intentional flows of lead within one model, which also includes the intentional flows. Application of the model shows that the non-intentional flows of lead related to waste streams associated with intentional use are decreasing over time, due to the increased attention given to waste management. However, as contaminants in mixed primary resources application, lead flows are increasing as demand for these applications is increasing.

  3. Environmental policy implications of working from home: Modelling the impacts of land-use, infrastructure and socio-demographics

    International Nuclear Information System (INIS)

    Fu Miao; Andrew Kelly, J.; Peter Clinch, J.; King, Fearghal

    2012-01-01

    Working from home is generally perceived as an effective means of reducing energy use and associated pollution from commuter transport. In order to consider the merits of mechanisms and policies to support a change in behaviour that results in greater take-up of home working, this paper applies energy consumption per commute calculations and a logit model using a case study of Ireland. In marked contrast with larger countries, the energy consumption per commute is relatively low in Ireland. Nonetheless, the analysis indicates that, on average, at least an average net saving of 9.33 kW h per day can be achieved where an individual converts to working from home, after deducting the home energy consumption associated with home working. We find that land use patterns, public transport networks, internet infrastructure, commute distances and socio-demographic characteristics can serve to influence rates of home working. Encouraging the higher and lower professional categories and those in the service sectors to work from home should be the highest priority in terms of energy and emissions reductions. Increased coverage of internet services and railway coverage will support higher rates of home working. Increased dispersion of residential, commercial and industrial areas serves to encourage greater home working. - Highlights: ► An average net energy saving of 9.33 kW h per day can be achieved by an individual changing to working from home. ► Land use patterns, public transport and internet infrastructure influence rates of home working. ► Commute distances and socio-demographic characteristics influence the take-up of home working. ► Encouraging home-working by higher and lower professionals and the service sectors is the priority.

  4. Demographical history and palaeodistribution modelling show range shift towards Amazon Basin for a Neotropical tree species in the LGM.

    Science.gov (United States)

    Vitorino, Luciana Cristina; Lima-Ribeiro, Matheus S; Terribile, Levi Carina; Collevatti, Rosane G

    2016-10-13

    We studied the phylogeography and demographical history of Tabebuia serratifolia (Bignoniaceae) to understand the disjunct geographical distribution of South American seasonally dry tropical forests (SDTFs). We specifically tested if the multiple and isolated patches of SDTFs are current climatic relicts of a widespread and continuously distributed dry forest during the last glacial maximum (LGM), the so called South American dry forest refugia hypothesis, using ecological niche modelling (ENM) and statistical phylogeography. We sampled 235 individuals of T. serratifolia in 17 populations in Brazil and analysed the polymorphisms at three intergenic chloroplast regions and ITS nuclear ribosomal DNA. Coalescent analyses showed a demographical expansion at the last c. 130 ka (thousand years before present). Simulations and ENM also showed that the current spatial pattern of genetic diversity is most likely due to a scenario of range expansion and range shift towards the Amazon Basin during the colder and arid climatic conditions associated with the LGM, matching the expected for the South American dry forest refugia hypothesis, although contrasting to the Pleistocene Arc hypothesis. Populations in more stable areas or with higher suitability through time showed higher genetic diversity. Postglacial range shift towards the Southeast and Atlantic coast may have led to spatial genome assortment due to leading edge colonization as the species tracks suitable environments, leading to lower genetic diversity in populations at higher distance from the distribution centroid at 21 ka. Haplotype sharing or common ancestry among populations from Caatinga in Northeast Brazil, Atlantic Forest in Southeast and Cerrado biome and ENM evince the past connection among these biomes.

  5. Antecedents and consequences of sexual harassment in organizations: a test of an integrated model.

    Science.gov (United States)

    Fitzgerald, L F; Drasgow, F; Hulin, C L; Gelfand, M J; Magley, V J

    1997-08-01

    Sexual harassment of women in organizational settings has recently become a topic of interest to researchers and the general public alike. Although numerous studies document its frequency, the development of conceptual models identifying antecedents and consequences of harassment has proceeded at a slower pace. In this article, an empirical test of a recently proposed conceptual model is described. According to the model, organizational climate for sexual harassment and job gender context are critical antecedents of sexual harassment; harassment, in turn, influences work-related variables (e.g., job satisfaction); psychological states (e.g., anxiety and depression); and physical health. On the basis of a sample of women employed at a large, regulated utility company, the model's predictions were generally supported.

  6. The design and application of a radiological consequence model for tropical and subtropical regions

    International Nuclear Information System (INIS)

    Domel, R.U.; Harris, F.F.; Crawford, J.

    1997-01-01

    The post Chernobyl era has seen the development of a plethora of radiological consequence models. At ANSTO, a model is being developed with a user-friendly interface which will assess the radiological consequences, after an incident, in tropical and sub-tropical climates. The model combines specific regional dispersion and deposition data to determine the dose to man via the major pathways of external and internal irradiation. The external irradiation data will need to include lifestyle information such as time spent L indoors/outdoors, the high/low activity times of the different groups of people (especially critical groups) and shielding factors for housing. The internal irradiation data requires food consumption values, effect of food processing and transfer parameters (soil to plant, plant to animal) to be obtained for tropical and sub-tropical regions. The model allows the user to specify the radionuclide of interest, the age of the person receiving l the dose, race, dietary components and lifestyle. The operator may use a number of default categories, but regional information may also be entered and incorporated into the radiological model allowing assessment of dose to critical groups using site specific data. Initially, the model will deal with the South East Asian region but flexibility has been incorporated into the design to allow application in other regions. A geographic information system is used for display of all input and output data allowing quick access to not only the results but also the underlying assumptions. The model also has portability across computer platforms. The model has been developed to provide a tool for directing future research, has application as a planing tool for emergency response operations but its priority lies in understanding the behaviour of radionuclides in the tropical and sub-tropical environments and their effect on humankind

  7. The modelling of off-site economic consequences of nuclear accidents

    International Nuclear Information System (INIS)

    Alonso, A.; Gallego, E.; Martin, J.E.

    1991-01-01

    The paper presents a computer model for the probabilistic assessment of the off-site economic risk derived from nuclear accidents. The model is called MECA (Model for Economic Consequence Assessment) and takes into consideration the direct costs caused, following an accident, by the different countermeasures adopted to prevent both the early and chronic exposure of the population to the radionuclides released, as well as the direct costs derived from health damage to the affected population. The model uses site-specific data that are organized in a socio-economic data base; detailed distributions of population, livestock census, agricultural production and farmland use, as well as of employment, salaries, and added value for different economic sectors are included. This data base has been completed for Spain, based on available official statistics. The new code, coupled to a general ACA code, provides capability to complete probabilistic risk assessments from the point of view of the off-site economic consequences, and also to perform cost-effectiveness analysis of the different countermeasures in the field of emergency preparedness

  8. Quantifying the predictive consequences of model error with linear subspace analysis

    Science.gov (United States)

    White, Jeremy T.; Doherty, John E.; Hughes, Joseph D.

    2014-01-01

    All computer models are simplified and imperfect simulators of complex natural systems. The discrepancy arising from simplification induces bias in model predictions, which may be amplified by the process of model calibration. This paper presents a new method to identify and quantify the predictive consequences of calibrating a simplified computer model. The method is based on linear theory, and it scales efficiently to the large numbers of parameters and observations characteristic of groundwater and petroleum reservoir models. The method is applied to a range of predictions made with a synthetic integrated surface-water/groundwater model with thousands of parameters. Several different observation processing strategies and parameterization/regularization approaches are examined in detail, including use of the Karhunen-Loève parameter transformation. Predictive bias arising from model error is shown to be prediction specific and often invisible to the modeler. The amount of calibration-induced bias is influenced by several factors, including how expert knowledge is applied in the design of parameterization schemes, the number of parameters adjusted during calibration, how observations and model-generated counterparts are processed, and the level of fit with observations achieved through calibration. Failure to properly implement any of these factors in a prediction-specific manner may increase the potential for predictive bias in ways that are not visible to the calibration and uncertainty analysis process.

  9. A Comparison of Grizzly Bear Demographic Parameters Estimated from Non-Spatial and Spatial Open Population Capture-Recapture Models.

    Science.gov (United States)

    Whittington, Jesse; Sawaya, Michael A

    2015-01-01

    Capture-recapture studies are frequently used to monitor the status and trends of wildlife populations. Detection histories from individual animals are used to estimate probability of detection and abundance or density. The accuracy of abundance and density estimates depends on the ability to model factors affecting detection probability. Non-spatial capture-recapture models have recently evolved into spatial capture-recapture models that directly include the effect of distances between an animal's home range centre and trap locations on detection probability. Most studies comparing non-spatial and spatial capture-recapture biases focussed on single year models and no studies have compared the accuracy of demographic parameter estimates from open population models. We applied open population non-spatial and spatial capture-recapture models to three years of grizzly bear DNA-based data from Banff National Park and simulated data sets. The two models produced similar estimates of grizzly bear apparent survival, per capita recruitment, and population growth rates but the spatial capture-recapture models had better fit. Simulations showed that spatial capture-recapture models produced more accurate parameter estimates with better credible interval coverage than non-spatial capture-recapture models. Non-spatial capture-recapture models produced negatively biased estimates of apparent survival and positively biased estimates of per capita recruitment. The spatial capture-recapture grizzly bear population growth rates and 95% highest posterior density averaged across the three years were 0.925 (0.786-1.071) for females, 0.844 (0.703-0.975) for males, and 0.882 (0.779-0.981) for females and males combined. The non-spatial capture-recapture population growth rates were 0.894 (0.758-1.024) for females, 0.825 (0.700-0.948) for males, and 0.863 (0.771-0.957) for both sexes. The combination of low densities, low reproductive rates, and predominantly negative population growth

  10. A Comparison of Grizzly Bear Demographic Parameters Estimated from Non-Spatial and Spatial Open Population Capture-Recapture Models.

    Directory of Open Access Journals (Sweden)

    Jesse Whittington

    Full Text Available Capture-recapture studies are frequently used to monitor the status and trends of wildlife populations. Detection histories from individual animals are used to estimate probability of detection and abundance or density. The accuracy of abundance and density estimates depends on the ability to model factors affecting detection probability. Non-spatial capture-recapture models have recently evolved into spatial capture-recapture models that directly include the effect of distances between an animal's home range centre and trap locations on detection probability. Most studies comparing non-spatial and spatial capture-recapture biases focussed on single year models and no studies have compared the accuracy of demographic parameter estimates from open population models. We applied open population non-spatial and spatial capture-recapture models to three years of grizzly bear DNA-based data from Banff National Park and simulated data sets. The two models produced similar estimates of grizzly bear apparent survival, per capita recruitment, and population growth rates but the spatial capture-recapture models had better fit. Simulations showed that spatial capture-recapture models produced more accurate parameter estimates with better credible interval coverage than non-spatial capture-recapture models. Non-spatial capture-recapture models produced negatively biased estimates of apparent survival and positively biased estimates of per capita recruitment. The spatial capture-recapture grizzly bear population growth rates and 95% highest posterior density averaged across the three years were 0.925 (0.786-1.071 for females, 0.844 (0.703-0.975 for males, and 0.882 (0.779-0.981 for females and males combined. The non-spatial capture-recapture population growth rates were 0.894 (0.758-1.024 for females, 0.825 (0.700-0.948 for males, and 0.863 (0.771-0.957 for both sexes. The combination of low densities, low reproductive rates, and predominantly negative

  11. MUSIDH, multiple use of simulated demographic histories, a novel method to reduce computation time in microsimulation models of infectious diseases.

    Science.gov (United States)

    Fischer, E A J; De Vlas, S J; Richardus, J H; Habbema, J D F

    2008-09-01

    Microsimulation of infectious diseases requires simulation of many life histories of interacting individuals. In particular, relatively rare infections such as leprosy need to be studied in very large populations. Computation time increases disproportionally with the size of the simulated population. We present a novel method, MUSIDH, an acronym for multiple use of simulated demographic histories, to reduce computation time. Demographic history refers to the processes of birth, death and all other demographic events that should be unrelated to the natural course of an infection, thus non-fatal infections. MUSIDH attaches a fixed number of infection histories to each demographic history, and these infection histories interact as if being the infection history of separate individuals. With two examples, mumps and leprosy, we show that the method can give a factor 50 reduction in computation time at the cost of a small loss in precision. The largest reductions are obtained for rare infections with complex demographic histories.

  12. Modeling a Civil Event Case Study for Consequence Management Using the IMPRINT Forces Module

    Science.gov (United States)

    Gacy, Marc; Gosakan, Mala; Eckdahl, Angela; Miller, Jeffrey R.

    2012-01-01

    A critical challenge in the Consequence Management (CM) domain is the appropriate allocation of necessary and skilled military and civilian personnel and materiel resources in unexpected emergencies. To aid this process we used the Forces module in the Improved Performance Research Integration Tool (IMPRINT). This module enables analysts to enter personnel and equipment capabilities, prioritized schedules and numbers available, along with unexpected emergency requirements in order to assess force response requirements. Using a suspected terrorist threat on a college campus, we developed a test case model which exercised the capabilities of the module, including the scope and scale of operations. The model incorporates data from multiple sources, including daily schedules and frequency of events such as fire calls. Our preliminary results indicate that the model can predict potential decreases in civilian emergency response coverage due to an involved unplanned incident requiring significant portions of police, fire and civil responses teams.

  13. A simplified model for calculating early offsite consequences from nuclear reactor accidents

    International Nuclear Information System (INIS)

    Madni, I.K.; Cazzoli, E.G.; Khatib-Rahbar, M.

    1988-07-01

    A personal computer-based model, SMART, has been developed that uses an integral approach for calculating early offsite consequences from nuclear reactor accidents. The solution procedure uses simplified meteorology and involves direct analytic integration of air concentration equations over time and position. This is different from the discretization approach currently used in the CRAC2 and MACCS codes. The SMART code is fast-running, thereby providing a valuable tool for sensitivity and uncertainty studies. The code was benchmarked against both MACCS version 1.4 and CRAC2. Results of benchmarking and detailed sensitivity/uncertainty analyses using SMART are presented. 34 refs., 21 figs., 24 tabs

  14. Escalation scenarios initiated by gas explosions on offshore installations. Probabilistic cause and consequence modelling

    Energy Technology Data Exchange (ETDEWEB)

    Eknes, Monika Loeland

    1996-12-31

    This Dr. ing. thesis deals with escalation scenarios initiated by gas explosions on offshore installations. Gas explosions is one of the major hazards to such installations. The objectives were to estimate the probability of ignition and frequency of gas explosions for gas leaks on top sides of offshore installations, and to estimate the response and resistance of components that could result in escalation if they failed. Main fields considered cover risk analysis methodology, gas explosions, simplified escalation models, evaluation of structural consequences, case studies, and guidelines. 107 refs., 33 figs., 33 tabs.

  15. Updates to the Demographic and Spatial Allocation Models to Produce Integrated Climate and Land Use Scenarios (ICLUS) (Version 2) (External Review Draft)

    Science.gov (United States)

    EPA announced the availability of the draft report, Updates to the Demographic and Spatial Allocation Models to Produce Integrated Climate and Land Use Scenarios (ICLUS) for a 30-day public comment period. The ICLUS version 2 (v2) modeling tool furthered land change mod...

  16. Demographic structure and macroeconomic trends

    OpenAIRE

    Aksoy, Yunus; Basso, H.S.; Smith, Ronald; Grasl, Tobias

    2018-01-01

    We estimate the effect of changes in demographic structure on long term\\ud trends of key macroeconomic variables using a Panel VAR for 21 OECD economies from 1970-2014. The panel data variation assists the identification of demographic effects, while the dynamic structure,\\ud incorporating multiple channels of influence, uncovers long-term effects.\\ud We propose a theoretical model, relating demographics, innovation and\\ud growth, whose simulations match our empirical findings. The current\\ud...

  17. Technology, Demographic Characteristics and E-Learning Acceptance: A Conceptual Model Based on Extended Technology Acceptance Model

    Science.gov (United States)

    Tarhini, Ali; Elyas, Tariq; Akour, Mohammad Ali; Al-Salti, Zahran

    2016-01-01

    The main aim of this paper is to develop an amalgamated conceptual model of technology acceptance that explains how individual, social, cultural and organizational factors affect the students' acceptance and usage behaviour of the Web-based learning systems. More specifically, the proposed model extends the Technology Acceptance Model (TAM) to…

  18. Comparison of the iPCoD and DEPONS models for modelling population consequences of noise on harbour porpoises

    DEFF Research Database (Denmark)

    Nabe-Nielsen, Jacob; Harwood, John

    Two different frameworks have been developed to assess the potential effects of noise associated with offshore renewable energy developments on harbour porpoise populations: The Interim Population Consequences of Disturbance (iPCoD) and Disturbance Effects of Noise on the Harbour Porpoise...... Population in the North Sea (DEPONS). Although both models simulate population dynamics based on the birth and survival rates of individual animals, they model survival in a different way. iPCoD uses average survival rates derived from data from North Sea animals. In the DEPONS model, survival emerges from...

  19. Review of models used for determining consequences of UF6 release: Model evaluation report. Volume 2

    International Nuclear Information System (INIS)

    Nair, S.K.; Chambers, D.B.; Park, S.H.; Radonjic, Z.R.; Coutts, P.T.; Lewis, C.J.; Hammonds, J.S.; Hoffman, F.O.

    1997-11-01

    Three uranium hexafluoride-(UF 6 -) specific models--HGSYSTEM/UF 6 , Science Application International Corporation, and RTM-96; three dense-gas models--DEGADIS, SLAB, and the Chlorine Institute methodology; and one toxic chemical model--AFTOX--are evaluated on their capabilities to simulate the chemical reactions, thermodynamics, and atmospheric dispersion of UF 6 released from accidents at nuclear fuel-cycle facilities, to support Integrated Safety Analysis, Emergency Response Planning, and Post-Accident Analysis. These models are also evaluated for user-friendliness and for quality assurance and quality control features, to ensure the validity and credibility of the results. Model performance evaluations are conducted for the three UF 6 -specific models, using field data on releases of UF 6 and other heavy gases. Predictions from the HGSYSTEM/UF 6 and SAIC models are within an order of magnitude of the field data, but the SAIC model overpredicts beyond an order of magnitude for a few UF 6 -specific data points. The RTM-96 model provides overpredictions within a factor of 3 for all data points beyond 400 m from the source. For one data set, however, the RTM-96 model severely underpredicts the observations within 200 m of the source. Outputs of the models are most sensitive to the meteorological parameters at large distances from the source and to certain source-specific and meteorological parameters at distances close to the source. Specific recommendations are being made to improve the applicability and usefulness of the three models and to choose a specific model to support the intended analyses. Guidance is also provided on the choice of input parameters for initial dilution, building wake effects, and distance to completion of UF 6 reaction with water

  20. Modelling Potential Consequences of Different Geo-Engineering Treatments for the Baltic Sea Ecosystem

    Science.gov (United States)

    Schrum, C.; Daewel, U.

    2017-12-01

    From 1950 onwards, the Baltic Sea ecosystem suffered increasingly from eutrophication. The most obvious reason for the eutrophication is the huge amount of nutrients (nitrogen and phosphorus) reaching the Baltic Sea from human activities. However, although nutrient loads have been decreasing since 1980, the hypoxic areas have not decreased accordingly. Thus, geo-engineering projects were discussed and evaluated to artificially ventilate the Baltic Sea deep water and suppress nutrient release from the sediments. Here, we aim at understanding the consequences of proposed geo-engineering projects in the Baltic Sea using long-term scenario modelling. For that purpose, we utilize a 3d coupled ecosystem model ECOSMO E2E, a novel NPZD-Fish model approach that resolves hydrodynamics, biogeochemical cycling and lower and higher trophic level dynamics. We performed scenario modelling that consider proposed geo-engineering projects such as artificial ventilation of Baltic Sea deep waters and phosphorus binding in sediments with polyaluminium chlorides. The model indicates that deep-water ventilation indeed suppresses phosphorus release in the first 1-4 years of treatment. Thereafter macrobenthos repopulates the formerly anoxic bottom regions and nutrients are increasingly recycled in the food web. Consequently, overall system productivity and fish biomass increases and toxic algae blooms decrease. However, deep-water ventilation has no long-lasting effect on the ecosystem: soon after completion of the ventilation process, the system turns back into its original state. Artificial phosphorus binding in sediments in contrast decreases overall ecosystem productivity through permanent removal of phosphorus. As expected it decreases bacterial production and toxic algae blooms, but it also decreases fish production substantially. Contrastingly to deep water ventilation, artificial phosphorus binding show a long-lasting effect over decades after termination of the treatment.

  1. [Antecedents and consequences of workplace bullying: a longitudinal analysis with a structural equation model].

    Science.gov (United States)

    Carretero Domínguez, Noelia; Gil-Monte, Pedro Rafael; Luciano Devis, Juan Vicente

    2011-11-01

    Most studies focusing on the antecedents and consequences of workplace bullying have used a cross-sectional design, which impedes determining the causality of the relationships. In the present work, we analyzed, by means of structural equation models, the relationship between workplace bullying and some variables that are considered antecedents (interpersonal conflicts, role ambiguity, role conflict, and workplace social support) or consequences (health complaints and inclination to absenteeism from work) of this phenomenon. Multicenter study with two phases. The sample consisted of 696 employees from 66 centers. Workplace bullying was assessed by means of the "Mobbing-UNIPSICO" questionnaire, and the other variables with frequency scales. The cross-sectional models indicated a significant association between role conflict, workplace social support, and workplace bullying in both study periods. Concerning the longitudinal relationships, only workplace social support was a significant predictor of workplace bullying, which, in turn, was a cross-sectional and longitudinal predictor of workers' health complaints. Our results show the mediating effect of workplace bullying between certain work conditions and health complaints, and it is recommendable to replicate these findings in a multi-occupational sample.

  2. Modelling the costs of care of hypertension in patients with metabolic syndrome and its consequences, in Germany, Spain and Italy.

    Science.gov (United States)

    Wille, Eberhard; Scholze, Jürgen; Alegria, Eduardo; Ferri, Claudio; Langham, Sue; Stevens, Warren; Jeffries, David; Uhl-Hochgraeber, Kerstin

    2011-06-01

    The presence of metabolic syndrome in patients with hypertension significantly increases the risk of cardiovascular disease, type 2 diabetes and mortality. Our aim is to estimate the economic burden to the health service of metabolic syndrome (MetS) in patients with hypertension and its consequences, in three European countries in 2008, and to forecast future economic burden in 2020 using projected demographic estimates and assumptions around the growth of MetS. An age-, sex- and risk group-structured prevalence-based cost of illness model was developed using the United States Adult Treatment Panel III of the National Cholesterol Education Program criteria to define MetS. Data sources included published information and public use databases on disease prevalence, incidence of cardiovascular events, prevalence of type 2 diabetes, treatment patterns and cost of management in Germany, Spain and Italy. The economic burden to the health service of MetS in patients with hypertension has been estimated at 24,427 euro, 1,900 euro and 4,877 euro million in Germany, Spain and Italy, and is forecast to rise by 59, 179 and 157%, respectively, by 2020. The largest components of costs included the management of prevalent type 2 diabetes and incident cardiovascular events. Mean annual costs per hypertensive patient were around three-fold higher in subjects with MetS compared to those without and rose incrementally with the additional number of MetS components present. In conclusion, the presence of MetS in patients with hypertension significantly inflates economic burden, and costs are likely to increase in the future due to an aging population and an increase in the prevalence of components of MetS.

  3. Modeling the Geographic Consequence and Pattern of Dengue Fever Transmission in Thailand.

    Science.gov (United States)

    Bekoe, Collins; Pansombut, Tatdow; Riyapan, Pakwan; Kakchapati, Sampurna; Phon-On, Aniruth

    2017-05-04

    Dengue fever is one of the infectious diseases that is still a public health problem in Thailand. This study considers in detail, the geographic consequence, seasonal and pattern of dengue fever transmission among the 76 provinces of Thailand from 2003 to 2015. A cross-sectional study. The data for the study was from the Department of Disease Control under the Bureau of Epidemiology, Thailand. The quarterly effects and location on the transmission of dengue was modeled using an alternative additive log-linear model. The model fitted well as illustrated by the residual plots and the  Again, the model showed that dengue fever is high in the second quarter of every year from May to August. There was an evidence of an increase in the trend of dengue annually from 2003 to 2015. There was a difference in the distribution of dengue fever within and between provinces. The areas of high risks were the central and southern regions of Thailand. The log-linear model provided a simple medium of modeling dengue fever transmission. The results are very important in the geographic distribution of dengue fever patterns.

  4. Accident consequence analysis models applied to licensing process of nuclear installations, radioactive and conventional industries

    International Nuclear Information System (INIS)

    Senne Junior, Murillo; Vasconcelos, Vanderley de; Jordao, Elizabete

    2002-01-01

    The industrial accidents happened in the last years, particularly in the eighty's decade, had contributed in a significant way to call the attention to government authorities, industry and society as a whole, demanding mechanisms for preventing episodes that could affect people's safety and environment quality. Techniques and methods already thoroughly used in the nuclear, aeronautic and war industries were then adapted for performing analysis and evaluation of the risks associated to other industrial activities, especially in the petroleum, chemistry and petrochemical areas. Some models for analyzing the consequences of accidents involving fire and explosion, used in the licensing processes of nuclear and radioactive facilities, are presented in this paper. These models have also application in the licensing of conventional industrial facilities. (author)

  5. Low-energy consequences of superstring-inspired models with intermediate-mass scales

    International Nuclear Information System (INIS)

    Gabbiani, F.

    1987-01-01

    The phenomenological consequences of implementing intermediate-mass scales in E 6 superstring-inspired models are discussed. Starting from a suitable Calabi-Yau compactification with b 1,1 >1, one gets, after Hosotani breaking, the rank r=5 gauge group SU(3) C x SU(2) L x U(1) Y x U(1) E , that is broken at an intermediate-mass scale down to the standard-model group. The analysis of both the intermediate and the electroweak breaking is performed in the two cases Λ c = M x and Λ c x , where Λ c is the scale at which the hidden sector gauginos condensate. It is performed quantitatively the minimization of the low-energy effective potential and the renormalization group analysis, yielding a viable set of mass spectra and confirming the reliability of the intermediate-breaking scheme

  6. Study of the hydroxyl radical: Experimental advances in microwave spectroscopy, theoretical model and astrophysical consequences

    International Nuclear Information System (INIS)

    Destombes, Jean-Luc

    1978-01-01

    This research thesis mainly addresses the experimental and theoretical study of the hydroxyl radical, and the consequences of the obtained results in astrophysics which are studied with a model of pumping by the far infrared. After a recall of notions related to microwave spectroscopy and to molecular radio-astronomy, the author more particularly discusses different aspects of microwave spectroscopy in the interstellar environment and in laboratory. He also reviews different types of spectrometers for unsteady molecules. In the second part, he addresses issues related to the hydroxyl radical (OH): presentation of spectrometers, study of the reaction environment, study of the radical microwave spectrum, identification of transitions by frequency measurements. In the last parts, the author addresses some aspects of interstellar OH masers, and reports the application of some results to simple models of pumping by the far infra red

  7. Bank of models for estimation of radioactive contamination consequences at the places where nuclear submarines are awaiting decommissioning

    International Nuclear Information System (INIS)

    Vorobiev, V.; Nosov, A.; Hitrikov, V.; Kiselev, V.; Korjov, M.; Krylov, A.; Kanevsky, M.; Petuhov, Y.

    1995-01-01

    The present paper presents a description of a computer bank of models for estimation of reactor accident consequences in harbors where Russian nuclear submarines are awaiting decommissioning. The computer bank is intended for an estimation of the consequences of a possible contamination of the surface water. It will also support the decision making in a tense situation. 2 figs., 1 tab

  8. Integrating data from multiple sources for insights into demographic processes: Simulation studies and proof of concept for hierarchical change-in-ratio models.

    Science.gov (United States)

    Nilsen, Erlend B; Strand, Olav

    2018-01-01

    We developed a model for estimating demographic rates and population abundance based on multiple data sets revealing information about population age- and sex structure. Such models have previously been described in the literature as change-in-ratio models, but we extend the applicability of the models by i) using time series data allowing the full temporal dynamics to be modelled, by ii) casting the model in an explicit hierarchical modelling framework, and by iii) estimating parameters based on Bayesian inference. Based on sensitivity analyses we conclude that the approach developed here is able to obtain estimates of demographic rate with high precision whenever unbiased data of population structure are available. Our simulations revealed that this was true also when data on population abundance are not available or not included in the modelling framework. Nevertheless, when data on population structure are biased due to different observability of different age- and sex categories this will affect estimates of all demographic rates. Estimates of population size is particularly sensitive to such biases, whereas demographic rates can be relatively precisely estimated even with biased observation data as long as the bias is not severe. We then use the models to estimate demographic rates and population abundance for two Norwegian reindeer (Rangifer tarandus) populations where age-sex data were available for all harvested animals, and where population structure surveys were carried out in early summer (after calving) and late fall (after hunting season), and population size is counted in winter. We found that demographic rates were similar regardless whether we include population count data in the modelling, but that the estimated population size is affected by this decision. This suggest that monitoring programs that focus on population age- and sex structure will benefit from collecting additional data that allow estimation of observability for different age- and

  9. Translating Institutional Templates: A Historical Account of the Consequences of Importing Policing Models into Argentina

    Directory of Open Access Journals (Sweden)

    Matías Dewey

    2017-01-01

    Full Text Available This article focuses on the translation of the French and English law enforcement models into Argentina and analyzes its consequences in terms of social order. Whereas in the former two models the judiciary and police institutions originated in large-scale processes of historical consolidation, in the latter these institutions were implanted without the antecedents present in their countries of origin. The empirical references are Argentine police institutions, particularly the police of the Buenos Aires Province, observed at two moments in which the institutional import was particularly intense: towards the end of the nineteenth and beginning of the twentieth centuries, and at the end of the twentieth century. By way of tracing these processes of police constitution and reform, we show how new models of law enforcement and policing interacted with indigenous political structures and cultural frames, as well as how this constellation produced a social order in which legality and illegality are closely interwoven. The article is an attempt to go beyond the common observations regarding how an imported model failed; instead, it dissects the effects the translation actually produced and how the translated models transform into resources that reshape the new social order. A crucial element, the article shows, is that these resources can be instrumentalized according to »idiosyncrasies«, interests, and quotas of power.

  10. Simple physics-based models of compensatory plant water uptake: concepts and eco-hydrological consequences

    Directory of Open Access Journals (Sweden)

    N. J. Jarvis

    2011-11-01

    Full Text Available Many land surface schemes and simulation models of plant growth designed for practical use employ simple empirical sub-models of root water uptake that cannot adequately reflect the critical role water uptake from sparsely rooted deep subsoil plays in meeting atmospheric transpiration demand in water-limited environments, especially in the presence of shallow groundwater. A failure to account for this so-called "compensatory" water uptake may have serious consequences for both local and global modeling of water and energy fluxes, carbon balances and climate. Some purely empirical compensatory root water uptake models have been proposed, but they are of limited use in global modeling exercises since their parameters cannot be related to measurable soil and vegetation properties. A parsimonious physics-based model of uptake compensation has been developed that requires no more parameters than empirical approaches. This model is described and some aspects of its behavior are illustrated with the help of example simulations. These analyses demonstrate that hydraulic lift can be considered as an extreme form of compensation and that the degree of compensation is principally a function of soil capillarity and the ratio of total effective root length to potential transpiration. Thus, uptake compensation increases as root to leaf area ratios increase, since potential transpiration depends on leaf area. Results of "scenario" simulations for two case studies, one at the local scale (riparian vegetation growing above shallow water tables in seasonally dry or arid climates and one at a global scale (water balances across an aridity gradient in the continental USA, are presented to illustrate biases in model predictions that arise when water uptake compensation is neglected. In the first case, it is shown that only a compensated model can match the strong relationships between water table depth and leaf area and transpiration observed in riparian forest

  11. Stressors, stress and stress consequences during long-duration manned space missions: a descriptive model

    Science.gov (United States)

    Geuna, Stefano; Brunelli, Francesco; Perino, Maria A.

    Keeping crew members in good health is a major factor in the success or failure of long-duration manned space missions. Among the many possible agents that can affect the crew's general well-being, stress is certainly one of the most critical because of its implications on human health and performance, both physical and mental. Nevertheless, very few studies have been performed on this fundamental issue and none of them has addressed it in its entirity, considering its diverse physical and psychological aspects. In this work, a descriptive model is proposed to expound the mechanism and sequence of events which mediate stress. A critical analysis of the information provided by past manned spaceflights and by dedicated research performed in analogous environments is presented, and an extrapolation of the available data on human stress in such extreme conditions is proposed. Both internal and external stressors have been identified, at physical and psychosocial levels, thus providing the basis for their early detection and preventive reduction. The possible negative consequences of stress that may lead to disease in crewmembers are described. Finally, the most effective instruments which may be of help in reducing space-related human stress and treating its negative consequences are suggested.

  12. Uncertainty and sensitivity analysis of early exposure results with the MACCS Reactor Accident Consequence Model

    International Nuclear Information System (INIS)

    Helton, J.C.; Johnson, J.D.; McKay, M.D.; Shiver, A.W.; Sprung, J.L.

    1995-01-01

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the early health effects associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 34 imprecisely known input variables on the following reactor accident consequences are studied: number of early fatalities, number of cases of prodromal vomiting, population dose within 10 mi of the reactor, population dose within 1000 mi of the reactor, individual early fatality probability within 1 mi of the reactor, and maximum early fatality distance. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: scaling factor for horizontal dispersion, dry deposition velocity, inhalation protection factor for nonevacuees, groundshine shielding factor for nonevacuees, early fatality hazard function alpha value for bone marrow exposure, and scaling factor for vertical dispersion

  13. Consequences of adolescent use of alcohol and other drugs: Studies using rodent models

    Science.gov (United States)

    Spear, Linda Patia

    2016-01-01

    Studies using animal models of adolescent exposure to alcohol, nicotine, cannabinoids, and the stimulants cocaine, 3,4-Methylenedioxymethampethamine and methamphetamine have revealed a variety of persisting neural and behavioral consequences. Affected brain regions often include mesolimbic and prefrontal regions undergoing notable ontogenetic change during adolescence, although it is unclear whether this represents areas of specific vulnerability or particular scrutiny to date. Persisting alterations in forebrain systems critical for modulating reward, socioemotional processing and cognition have emerged, including apparent induction of a hyper-dopaminergic state with some drugs and/or attenuations in neurons expressing cholinergic markers. Disruptions in cognitive functions such as working memory, alterations in affect including increases in social anxiety, and mixed evidence for increases in later drug self-administration have also been reported. When consequences of adolescent and adult exposure were compared, adolescents were generally found to be more vulnerable to alcohol, nicotine, and cannabinoids, but generally not to stimulants. More work is needed to determine how adolescent drug exposure influences sculpting of the adolescent brain, and provide approaches to prevent/reverse these effects. PMID:27484868

  14. Modeling T-cell proliferation: an investigation of the consequences of the Hayflick limit.

    Science.gov (United States)

    Pilyugin, S; Mittler, J; Antia, R

    1997-05-07

    Somatic cells, including immune cells such as T-cells have a limited capacity for proliferation and can only replicate for a finite number of generations (known as the Hayflick limit) before dying. In this paper we use mathematical models to investigate the consequences of introducing a Hayflick limit on the dynamics of T-cells stimulated with specific antigen. We show that while the Hayflick limit does not alter the dynamics of T-cell response to antigen over the short term, it may have a profound effect on the long-term immune response. In particular we show that over the long term the Hayflick limit may be important in determining whether an immune response can be maintained to a persistent antigen (or parasite). The eventual outcome is determined by the magnitude of the Hayflick limit, the extent to which antigen reduces the input of T-cells from the thymus, and the rate of antigen-induced proliferation of T-cells. Counter to what might be expected we show that the persistence of an immune response (immune memory) requires the density of persistent antigen to be less than a defined threshold value. If the amount of persistent antigen (or parasite) is greater than this threshold value then immune memory will be relatively short lived. The consequences of this threshold for persistent mycobacterial and HIV infections and for the generation of vaccines are discussed.

  15. Model to predict radiological consequences of transportation accidents involving dispersal of radioactive material in urban areas

    International Nuclear Information System (INIS)

    Taylor, J.M.; Daniel, S.L.

    1978-01-01

    The analysis of accidental releases of radioactive material which may result from transportation accidents in high-density urban areas is influenced by several urban characteristics which make computer simulation the calculational method of choice. These urban features fall into four categories. Each of these categories contains time- and location-dependent parameters which must be coupled to the actual time and location of the release in the calculation of the anticipated radiological consequences. Due to the large number of dependent parameters a computer model, METRAN, has been developed to quantify these radiological consequences. Rather than attempt to describe an urban area as a single entity, a specific urban area is subdivided into a set of cells of fixed size to permit more detailed characterization. Initially, the study area is subdivided into a set of 2-dimensional cells. A uniform set of time-dependent physical characteristics which describe the land use, population distribution, traffic density, etc., within that cell are then computed from various data sources. The METRAN code incorporates several details of urban areas. A principal limitation of the analysis is the limited availability of accurate information to use as input data. Although the code was originally developed to analyze dispersal of radioactive material, it is currently being evaluated for use in analyzing the effects of dispersal of other hazardous materials in both urban and rural areas

  16. A model for the calculation of the off-site economic consequences of nuclear reactor accidents

    International Nuclear Information System (INIS)

    Gallego, E.; Alonso, A.

    1988-01-01

    The off-site economic cost of nuclear reactor accidents will depend on the countermeasures adopted to reduce its radiological impact. The assessment of the direct costs of emergency countermeasures (evacuation, early relocation and food disposal) as well as those of long-term protective actions (food disposal, decontamination or interdiction) is the objective of a model under development, with the sponsorship of the CEC Radiation Protection Programme, called MECA (Model for assessing the Economic Consequences of Accidents). The meteorological and socio-economical peculiarities of each site studied will be taken into account, by means of a flexible meteorological sampling scheme, which considers the geographical distribution of population and economic centers, and a data-base, compatible with the existing European grid, that contains the population distribution and the economic characteristics of the environs of the site to be studied with more detail near the reactor. The paper summarizes the particular models which will be included in MECA and shows the importance of site-specific adaptable modelling for economic risk evaluation

  17. Using an ethical decision-making model to determine consequences for student plagiarism.

    Science.gov (United States)

    Kiehl, Ermalynn M

    2006-06-01

    The incidence of plagiarism, intentional or unintentional, in the professional nursing arena has increased in recent years, as has the occurrence of plagiarism among nursing students. Strategies for cheating have become very sophisticated with the use of aids such as personal digital assistants, camera phones, and instant messaging. Cheating on written papers has also increased. The Internet provides students with ready-made research and academic papers, and access to Web sites on a plethora of topics. In this article, I describe my experience with plagiarism of ethics papers during students' final semester before graduation. How I discovered the plagiarized work and used the A-B-C-D-E ethical decision-making model in determining the student consequences for the event are presented.

  18. SOFTWARE QUALITY ASSURANCE FOR EMERGENCY RESPONSE CONSEQUENCE ASSESSMENT MODELS AT DOE'S SAVANNAH RIVER SITE

    International Nuclear Information System (INIS)

    Hunter, C

    2007-01-01

    The Savannah River National Laboratory's (SRNL) Atmospheric Technologies Group develops, maintains, and operates computer-based software applications for use in emergency response consequence assessment at DOE's Savannah River Site. These applications range from straightforward, stand-alone Gaussian dispersion models run with simple meteorological input to complex computational software systems with supporting scripts that simulate highly dynamic atmospheric processes. A software quality assurance program has been developed to ensure appropriate lifecycle management of these software applications. This program was designed to meet fully the overall structure and intent of SRNL's institutional software QA programs, yet remain sufficiently practical to achieve the necessary level of control in a cost-effective manner. A general overview of this program is described

  19. Origins and consequences of technology acquirement by independent-living seniors: towards an integrative model.

    Science.gov (United States)

    Peek, S T M; Luijkx, K G; Vrijhoef, H J M; Nieboer, M E; Aarts, S; van der Voort, C S; Rijnaard, M D; Wouters, E J M

    2017-08-22

    Living independently can be challenging for seniors. Technologies are expected to help older adults age in place, yet little empirical research is available on how seniors develop a need for technologies, how they acquire these technologies, and how these subsequently affect their lives. Aging is complex, dynamic and personal. But how does this translate to seniors' adoption and acceptance of technology? To better understand origins and consequences of technology acquirement by independent-living seniors, an explorative longitudinal qualitative field study was set up. Home visits were made to 33 community-dwelling seniors living in the Netherlands, on three occasions (2012-2014). Semi-structured interviews were conducted on the timeline of acquirements, and people and factors involved in acquirements. Additionally, participants were interviewed on experiences in using technologies since acquirement. Thematic analysis was employed to analyze interview transcripts, using a realist approach to better understand the contexts, mechanisms and outcomes of technology acquirements. Findings were accumulated in a new conceptual model: The Cycle of Technology Acquirement by Independent-Living Seniors (C-TAILS), which provides an integrative perspective on why and how technologies are acquired, and why these may or may not prove to be appropriate and effective, considering an independent-living senior's needs and circumstances at a given point in time. We found that externally driven and purely desire-driven acquirements led to a higher risk of suboptimal use and low levels of need satisfaction. Technology acquirement by independent-living seniors may be best characterized as a heterogeneous process with many different origins, pathways and consequences. Furthermore, technologies that are acquired in ways that are not congruent with seniors' personal needs and circumstances run a higher risk of proving to be ineffective or inappropriate. Yet, these needs and circumstances are

  20. Demonstration uncertainty/sensitivity analysis using the health and economic consequence model CRAC2

    International Nuclear Information System (INIS)

    Alpert, D.J.; Iman, R.L.; Johnson, J.D.; Helton, J.C.

    1984-12-01

    The techniques for performing uncertainty/sensitivity analyses compiled as part of the MELCOR program appear to be well suited for use with a health and economic consequence model. Two replicate samples of size 50 gave essentially identical results, indicating that for this case, a Latin hypercube sample of size 50 seems adequate to represent the distribution of results. Though the intent of this study was a demonstration of uncertainty/sensitivity analysis techniques, a number of insights relevant to health and economic consequence modeling can be gleaned: uncertainties in early deaths are significantly greater than uncertainties in latent cancer deaths; though the magnitude of the source term is the largest source of variation in estimated distributions of early deaths, a number of additional parameters are also important; even with the release fractions for a full SST1, one quarter of the CRAC2 runs gave no early deaths; and comparison of the estimates of mean early deaths for a full SST1 release in this study with those of recent point estimates for similar conditions indicates that the recent estimates may be significant overestimations of early deaths. Estimates of latent cancer deaths, however, are roughly comparable. An analysis of the type described here can provide insights in a number of areas. First, the variability in the results gives an indication of the potential uncertainty associated with the calculations. Second, the sensitivity of the results to assumptions about the input variables can be determined. Research efforts can then be concentrated on reducing the uncertainty in the variables which are the largest contributors to uncertainty in results

  1. Investigating attribute non-attendance and its consequences in choice experiments with latent class models.

    Science.gov (United States)

    Lagarde, Mylene

    2013-05-01

    A growing literature, mainly from transport and environment economics, has started to explore whether respondents violate some of the axioms about individuals' preferences in Discrete Choice Experiments (DCEs) and use simple strategies to make their choices. One of these strategies, termed attribute non-attendance (ANA), consists in ignoring one or more attributes. Using data from a DCE administered to healthcare providers in Ghana to evaluate their potential resistance to changes in clinical guidelines, this study illustrates how latent class models can be used in a step-wise approach to account for all possible ANA strategies used by respondents and explore the consequences of such behaviours. Results show that less than 3% of respondents considered all attributes when choosing between the two hypothetical scenarios proposed, with a majority looking at only one or two attributes. Accounting for ANA strategies improved the goodness-of-fit of the model and affected the magnitude of some of the coefficient and willingness-to-pay estimates. However, there was no difference in the predicted probabilities of the model taking into account ANA and the standard approach. Although the latter result is reassuring about the ability of DCEs to produce unbiased policy guidance, it should be confirmed by other studies. Copyright © 2012 John Wiley & Sons, Ltd.

  2. RadCon: A radiological consequences model. Technical guide - Version 2.0

    International Nuclear Information System (INIS)

    Crawford, J; Domel, R.U.; Harris, F.F.; Twining, J.R.

    2000-05-01

    A Radiological Consequence model (RadCon) is being developed at ANSTO to assess the radiological consequences, after an incident, in any climate, using appropriate meteorological and radiological transfer parameters. The major areas of interest to the developers are tropical and subtropical climates. This is particularly so given that it is anticipated that nuclear energy will become a mainstay for economies in these regions within the foreseeable future. Therefore, data acquisition and use of parameter values have been concentrated primarily on these climate types. Atmospheric dispersion and deposition for Australia can be modelled and supplied by the Regional Specialised Meteorological Centre (RSMC, one of five in the world) which is part of the Bureau of Meteorology Research Centre (BMRC), Puri et al. (1992). RadCon combines these data (i.e. the time dependent air and ground concentration generated by the dispersion model or measured quantities in the case of an actual incident) with specific regional parameter values to determine the dose to people via the major pathways of external and internal irradiation. For the external irradiation calculations, data are needed on lifestyle information such as the time spent indoors/outdoors, the high/low physical activity rates for different groups of people (especially critical groups) and shielding factors for housing types. For the internal irradiation calculations, data are needed on food consumption, effect of food processing, transfer parameters (soil to plant, plant to animal) and interception values appropriate for the region under study. Where the relevant data are not available default temperate data are currently used. The results of a wide ranging literature search has highlighted where specific research will be initiated to determine the information required for tropical and sub-tropical regions. The user is able to initiate sensitivity analyses within RadCon. This allows the parameters to be ranked in

  3. Influencing Factors and Consequences of Workplace Bullying among Nurses: A Structural Equation Modeling

    Directory of Open Access Journals (Sweden)

    Seonyoung Yun, PhD, RN

    2018-03-01

    Full Text Available Purpose: The purpose of this study was to build and test a model outlining the factors related to workplace bullying among nurses. The hypothesized model included authentic leadership and a relationship-oriented organizational culture as influencing factors, symptom experience and turnover intention as consequences, and positive psychological capital as a mediator of workplace bullying among nurses. Methods: We obtained structured questionnaire data from 301 nurses working at hospitals in South Korea. Based on these data, the developed model was verified via a structural equation modeling analysis using SPSS and AMOS program. Results: The fit indices of the hypothesized model satisfied recommended levels; χ2 = 397.58 (p < .001, normed χ2 (χ2/df = 1.82, RMR = .05, TLI = .93, CFI = .94, RMSEA = .05. A relationship-oriented organizational culture had a direct effect on workplace bullying (β = −.48, p < .001. Furthermore, workplace bullying had a direct effect on symptom experience (β = .36, p < .001, and this relationship was mediated by positive psychological capital (β = .15, p = .003. Workplace bullying also had an indirect effect on turnover intention (β = .20, p = .007. Finally, symptom experience had a direct effect on turnover intention (β = .31, p = .002. Conclusion: These results suggest that workplace bullying among nurses may be prevented by constructing a relationship-oriented organizational culture, as long as employees have sufficient positive psychological capital. In this regard, workplace bullying among nurses should be addressed using a comprehensive strategy that considers both individual and organizational factors. Keywords: bullying, leadership, nurses, organizational culture, personnel turnover

  4. Comparison of the foodchain transport models of WASH-1400 and MARC using the accident consequence model UFOMOD

    International Nuclear Information System (INIS)

    Steinhauer, C.

    1985-04-01

    Within the frame of the contract with the European Community 'Methods for Assessing the Radiological Impact of Accidents' (CEC-MARIA) comparative accident consequence assessments were performed with the computer code UFOMOD, replacing the currently implemented foodchain transport model of the WASH-1400 study by the dynamic transport model of the MARC methodology. The calculations were based on the release category FK2 of the German Risk Study with meteorological data representing four different regions of the Federal Republic of Germany. The study of seasonal variations was carried out with the MARC data for four representative times of deposition with an agricultural practice adopted in the UK. In this report the differences are presented which are observed in the potential doses due to ingestion, the areas affected by food-bans and the late health effects when using both models and taking the influence of seasonal effects into account. (orig.) [de

  5. Mixed effects modeling of proliferation rates in cell-based models: consequence for pharmacogenomics and cancer.

    Directory of Open Access Journals (Sweden)

    Hae Kyung Im

    2012-02-01

    Full Text Available The International HapMap project has made publicly available extensive genotypic data on a number of lymphoblastoid cell lines (LCLs. Building on this resource, many research groups have generated a large amount of phenotypic data on these cell lines to facilitate genetic studies of disease risk or drug response. However, one problem that may reduce the usefulness of these resources is the biological noise inherent to cellular phenotypes. We developed a novel method, termed Mixed Effects Model Averaging (MEM, which pools data from multiple sources and generates an intrinsic cellular growth rate phenotype. This intrinsic growth rate was estimated for each of over 500 HapMap cell lines. We then examined the association of this intrinsic growth rate with gene expression levels and found that almost 30% (2,967 out of 10,748 of the genes tested were significant with FDR less than 10%. We probed further to demonstrate evidence of a genetic effect on intrinsic growth rate by determining a significant enrichment in growth-associated genes among genes targeted by top growth-associated SNPs (as eQTLs. The estimated intrinsic growth rate as well as the strength of the association with genetic variants and gene expression traits are made publicly available through a cell-based pharmacogenomics database, PACdb. This resource should enable researchers to explore the mediating effects of proliferation rate on other phenotypes.

  6. Uncertainty and sensitivity analysis of chronic exposure results with the MACCS reactor accident consequence model

    International Nuclear Information System (INIS)

    Helton, J.C.; Johnson, J.D.; Rollstin, J.A.; Shiver, A.W.; Sprung, J.L.

    1995-01-01

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the chronic exposure pathways associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 75 imprecisely known input variables on the following reactor accident consequences are studied: crop growing season dose, crop long-term dose, water ingestion dose, milk growing season dose, long-term groundshine dose, long-term inhalation dose, total food pathways dose, total ingestion pathways dose, total long-term pathways dose, total latent cancer fatalities, area-dependent cost, crop disposal cost, milk disposal cost, population-dependent cost, total economic cost, condemnation area, condemnation population, crop disposal area and milk disposal area. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: dry deposition velocity, transfer of cesium from animal feed to milk, transfer of cesium from animal feed to meat, ground concentration of Cs-134 at which the disposal of milk products will be initiated, transfer of Sr-90 from soil to legumes, maximum allowable ground concentration of Sr-90 for production of crops, fraction of cesium entering surface water that is consumed in drinking water, groundshine shielding factor, scale factor defining resuspension, dose reduction associated with decontamination, and ground concentration of 1-131 at which disposal of crops will be initiated due to accidents that occur during the growing season

  7. Uncertainty and sensitivity analysis of food pathway results with the MACCS Reactor Accident Consequence Model

    International Nuclear Information System (INIS)

    Helton, J.C.; Johnson, J.D.; Rollstin, J.A.; Shiver, A.W.; Sprung, J.L.

    1995-01-01

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the food pathways associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 87 imprecisely-known input variables on the following reactor accident consequences are studied: crop growing season dose, crop long-term dose, milk growing season dose, total food pathways dose, total ingestion pathways dose, total long-term pathways dose, area dependent cost, crop disposal cost, milk disposal cost, condemnation area, crop disposal area and milk disposal area. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: fraction of cesium deposition on grain fields that is retained on plant surfaces and transferred directly to grain, maximum allowable ground concentrations of Cs-137 and Sr-90 for production of crops, ground concentrations of Cs-134, Cs-137 and I-131 at which the disposal of milk will be initiated due to accidents that occur during the growing season, ground concentrations of Cs-134, I-131 and Sr-90 at which the disposal of crops will be initiated due to accidents that occur during the growing season, rate of depletion of Cs-137 and Sr-90 from the root zone, transfer of Sr-90 from soil to legumes, transfer of Cs-137 from soil to pasture, transfer of cesium from animal feed to meat, and the transfer of cesium, iodine and strontium from animal feed to milk

  8. Uncertainty and sensitivity analysis of food pathway results with the MACCS reactor accident consequence model

    International Nuclear Information System (INIS)

    Helton, J.C.; Johnson, J.D.; Rollstin, J.A.; Shiver, A.W.; Sprung, J.L.

    1995-01-01

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the food pathways associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 87 imprecisely-known input variables on the following reactor accident consequences are studied: crop growing-season dose, crop long-term dose, milk growing-season dose, total food pathways dose, total ingestion pathways dose, total long-term pathways dose, area dependent cost, crop disposal cost, milk disposal cost, condemnation area, crop disposal area and milk disposal area. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: fraction of cesium deposition on grain fields that is retained on plant surfaces and transferred directly to grain, maximum allowable ground concentrations of Cs-137 and Sr-90 for production of crops, ground concentrations of Cs-134, Cs-137 and I-131 at which the disposal of milk will be initiated due to accidents that occur during the growing season, ground concentrations of Cs-134, I-131 and Sr-90 at which the disposal of crops will be initiated due to accidents that occur during the growing season, rate of depletion of Cs-137 and Sr-90 from the root zone, transfer of Sr-90 from soil to legumes, transfer of Cs-137 from soil to pasture, transfer of cesium from animal feed to meat, and the transfer of cesium, iodine and strontium from animal feed to milk

  9. Uncertainty and sensitivity analysis of chronic exposure results with the MACCS reactor accident consequence model

    International Nuclear Information System (INIS)

    Helton, J.C; Johnson, J.D; Rollstin, J.A; Shiver, A.W; Sprung, J.L

    1995-01-01

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the chronic exposure pathways associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 75 imprecisely known input variables on the following reactor accident consequences are studied: crop growing-season dose, crop long-term dose, water ingestion dose, milk growing-season dose, long-term groundshine dose, long-term inhalation dose, total food pathways dose, total ingestion pathways dose, total long-term pathways dose, total latent cancer fatalities, area-dependent cost, crop disposal cost, milk disposal cost, population-dependent cost, total economic cost, condemnation area, condemnation population, crop disposal area and milk disposal area. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: dry deposition velocity, transfer of cesium from animal feed to milk, transfer of cesium from animal feed to meet, ground concentration of Cs-134 at which the disposal of milk products will be initiated, transfer of Sr-90 from soil to legumes, maximum allowable ground concentration of Sr-90 for production of crops, fraction of cesium entering surface water that is consumed in drinking water, groundshine shielding factor, scale factor defining resuspension, dose reduction associated with decontamination, and ground concentration of I-131 at which disposal of crops will be initiated due to accidents that occur during the growing season. Reducing the uncertainty in the preceding variables was found to substantially reduce the uncertainty in the

  10. A likely universal model of fracture scaling and its consequence for crustal hydromechanics

    Science.gov (United States)

    Davy, P.; Le Goc, R.; Darcel, C.; Bour, O.; de Dreuzy, J. R.; Munier, R.

    2010-10-01

    We argue that most fracture systems are spatially organized according to two main regimes: a "dilute" regime for the smallest fractures, where they can grow independently of each other, and a "dense" regime for which the density distribution is controlled by the mechanical interactions between fractures. We derive a density distribution for the dense regime by acknowledging that, statistically, fractures do not cross a larger one. This very crude rule, which expresses the inhibiting role of large fractures against smaller ones but not the reverse, actually appears be a very strong control on the eventual fracture density distribution since it results in a self-similar distribution whose exponents and density term are fully determined by the fractal dimension D and a dimensionless parameter γ that encompasses the details of fracture correlations and orientations. The range of values for D and γ appears to be extremely limited, which makes this model quite universal. This theory is supported by quantitative data on either fault or joint networks. The transition between the dilute and dense regimes occurs at about a few tenths of a kilometer for faults systems and a few meters for joints. This remarkable difference between both processes is likely due to a large-scale control (localization) of the fracture growth for faulting that does not exist for jointing. Finally, we discuss the consequences of this model on the flow properties and show that these networks are in a critical state, with a large number of nodes carrying a large amount of flow.

  11. New animal model of emotional stress: Behavioral, neuroendocrine and immunological consequences

    Institute of Scientific and Technical Information of China (English)

    LIN Wenjuan; WANG Weiwen; SHAO Feng

    2003-01-01

    This report describes a new model of emotional stress, which was induced by randomly giving an empty water bottle to rats during watering periods per day for 14 consecutive days. The behavioral, endocrinological and immunological consequences were investigated. The data showed that the emotional stress activated both the hypothalamic-pituitary-adrenal axis and the sympathetic nervous system, leading to the increased blood levels of corticosterone and catecholamine. It also elicited attacking and exploring behavior, suppressed the immune function of the rats, including leukocyte counts, weight of the spleen, and the level of specific anti-ovalbumin IgG antibody production. Presenting no water and no empty bottle to rats only evoked the exploring behavior, increased the corticosterone level and decreased the leukocyte counts. These findings demonstrate a role of psychological factors on behavioral, endocrinological and immunological functioning. The animal model described in the present study may serve as an analogue mimicking emotional stress experienced in humans (e.g. anger and/or anxiety), and may be useful for further studying the complex relationships among emotional stress, behavior, and immune function.

  12. A dynamic food-chain model and program for predicting the radiological consequences of nuclear accident

    International Nuclear Information System (INIS)

    Hu Erbang; Gao Zhanrong; Zhang Heyuan; Wei Weiqiang

    1996-12-01

    A dynamic food-chain model and program, DYFOM-95, for predicting the radiological consequences of nuclear accident has been developed, which is not only suitable to the West food-chain but also to Chinese food chain. The following processes, caused by accident release which will make an impact on radionuclide concentration in the edible parts of vegetable are considered: dry and wet deposition interception and initial retention, translocation, percolation, root uptake and tillage. Activity intake rate of animals, effects of processing and activity intake of human through ingestion pathway are also considered in calculations. The effects of leaf area index LAI of vegetable are considered in dry deposition model. A method for calculating the contribution of rain with different period and different intensity to total wet deposition is established. The program contains 1 main code and 5 sub-codes to calculate dry and wet deposition on surface of vegetable and soil, translocation of nuclides in vegetable, nuclide concentration in the edible parts of vegetable and in animal products and activity intake of human and so on. (24 refs., 9 figs., 11 tabs.)

  13. Motivation for Palatable Food Despite Consequences in an Animal Model of Binge-Eating

    Science.gov (United States)

    Oswald, Kimberly D.; Murdaugh, Donna L.; King, Vinetra L.; Boggiano, Mary M.

    2010-01-01

    Objective Binge-eating involves an abnormal motivation for highly palatable food in that these foods are repeatedly consumed despite their binge-triggering effects and life-affecting consequences associated with binge-eating. We determined if rats identified as binge-eating prone (BEP) similarly display abnormal motivation for palatable food. Method Food-sated BEP and binge-eating resistant (BER) rats were given voluntary access to palatable food paired with increasing intensity of footshock. Later, they were exposed to a period of cyclic caloric restriction-refeeding. Results BEPs consumed significantly more and tolerated higher levels of footshock for palatable food than BERs. Cyclic restriction-refeeding increased BERs' tolerance of shock for palatable food. Discussion Previously observed parallels of the rat BEP model to human binge-eating can now be extended to include an abnormal motivation for palatable food. This model should prove useful in identifying specific genes that interact with the nutritional environment to mediate binge-eating and may point to novel physiological targets to treat compulsive overeating. PMID:20186718

  14. Motivation for palatable food despite consequences in an animal model of binge eating.

    Science.gov (United States)

    Oswald, Kimberly D; Murdaugh, Donna L; King, Vinetra L; Boggiano, Mary M

    2011-04-01

    Binge eating involves an abnormal motivation for highly palatable food in that these foods are repeatedly consumed despite their binge-triggering effects and life-affecting consequences associated with binge eating. We determined if rats identified as binge-eating prone (BEP) similarly display abnormal motivation for palatable food. Food-sated BEP and binge-eating resistant (BER) rats were given voluntary access to palatable food paired with increasing intensity of footshock. Later, they were exposed to a period of cyclic caloric restriction-refeeding. BEPs consumed significantly more and tolerated higher levels of footshock for palatable food than BERs. Cyclic restriction-refeeding increased BERs' tolerance of shock for palatable food. Previously observed parallels of the rat BEP model to human binge eating can now be extended to include an abnormal motivation for palatable food. This model should prove useful in identifying specific genes that interact with the nutritional environment to mediate binge eating and may point to novel physiological targets to treat compulsive overeating. Copyright © 2010 Wiley Periodicals, Inc.

  15. Source-Term and building-Wake Consequence Modeling for the Godiva IV Reactor at Los Alamos National Laboratory

    International Nuclear Information System (INIS)

    Letellier, B.C.; McClure, P.; Restrepo, L.

    1999-01-01

    The objectives of this work were to evaluate the consequences of a postulated accident to onsite security personnel stationed near the facility during operations of the Godiva IV critical assembly and to identify controls needed to protect these personnel in case of an extreme criticality excursion equivalent to the design-basis accident (DBA). This paper presents the methodology and results of the source-term calculations, building ventilation rates, air concentrations, and consequence calculations that were performed using a multidisciplinary approach with several phenomenology models. Identification of controls needed to mitigate the consequences to near-field receptors is discussed

  16. Modelling the costs and consequences of treating paediatric faecal impaction in Australia.

    Science.gov (United States)

    Guest, Julian F; Clegg, John P

    2006-01-01

    To compare the costs and consequences of using oral macrogol 3350 plus electrolytes (macrogol 3350; Movicol) compared to enemas/suppositories, manual evacuation and naso-gastric administration of macrogol (NGA-PEG) lavage solution in treating paediatric faecal impaction in Australia. A decision model was constructed using published clinical outcomes, utilities and clinician-derived resource utilisation estimates. The model was used to determine the expected Commonwealth and parent costs associated with each treatment over the period of disimpaction and 12 weeks post-disimpaction, in Australian dollars at 2003/2004 prices. 92% of oral macrogol 3350-treated patients are expected to be disimpacted within 6 days following initial treatment, compared with 79% of patients treated with enemas and suppositories who are expected to be disimpacted within 8 days. All patients are expected to be disimpacted within 5 days following a manual evacuation and within 2 days following NGA-PEG. The level of health gain at 12 weeks post-disimpaction irrespective of treatment for disimpaction and subsequent maintenance is expected to be the same; the expected quality-adjusted life years (QALYs) being 0.20 (95% CI: 0.17; 0.23). Starting treatment with oral macrogol 3350 in an outpatient setting is expected to lead to a Commonwealth cost of $758, compared to $1838 with NGA-PEG, $2125 with enemas and suppositories, $3931 with oral macrogol 3350 in an inpatient setting and $4478 with manual evacuation. Resource use associated with maintenance following initial disimpaction is expected to be broadly similar, irrespective of initial laxative. Hence, the expected Commonwealth cost is primarily affected by the treatment used to initially disimpact a patient. Expected parents' costs are expected to be comparable irrespective of treatment ranging from $89 to $112 per patient. Within the limitations of our model, using oral macrogol 3350 in an outpatient setting for treating faecally impacted

  17. Physiological consequences of CPAP therapy withdrawal in patients with obstructive sleep apnoea—an opportunity for an efficient experimental model

    OpenAIRE

    Schwarz, Esther I.; Stradling, John R.; Kohler, Malcolm

    2018-01-01

    Randomised controlled trials (RCTs) of continuous positive airway pressure (CPAP) in obstructive sleep apnoea (OSA) are time consuming, and their findings often inconclusive or limited due to suboptimal CPAP adherence in CPAP-naïve patients with OSA. Short-term CPAP withdrawal in patients with prior optimal CPAP adherence results in recurrence of OSA and its consequences. Thus, this experimental model serves as an efficient tool to investigate both the consequences of untreated OSA, and poten...

  18. Vertebrates population response to the climatic change - pertinence of the environmental indicators and influence of the demographic strategies and consequences for the biodiversity dynamic; Reponses demographiques des vertebres aux changements climatiques - pertinence d'indicateurs environnementaux et influence des strategies demographiques et consequences pour la dynamique de la biodiversite

    Energy Technology Data Exchange (ETDEWEB)

    Weimerskirch, H

    2007-07-01

    There is a growing interest and major challenge to understand the way environmental variability and climatic change have affected and will affect ecosystems and populations. Long-term records of population parameters of vertebrates are rare, but invaluable to address this challenge. The network CLIMPOP brings together French researchers working with long term data collected on individually marked animals to study the effects of climate change on a range of vertebrate populations (reptiles, birds and mammals) and standardised methods to link climatic factors and demographic parameters. The funding from GICC-IFB has allowed the CLIMPOP group to hire a post doc bridging methodologists and ecologists, organize a workshop and support field studies. Several analyses on a series of vertebrates have been carried out on the link between large-scale and small-scale climatic factors and population dynamics. In addition the CLIMPOP group has carried out a major methodological paper reviewing statistical models and procedures to study the influence of climate on vital rates based on the analysis of individual monitoring data, to identify potential pitfalls in the utilization of these models and procedures, to review published papers in which the influence of climatic variation on survival probability in vertebrate populations has been addressed, to evaluate whether the results from these studies are relevant and to draw practical recommendations to efficiently address effects of climate effects on vital rates in natural vertebrate populations. This evaluation raised six potential methodological issues and indicates that so far most of the studies found in the ecological literature can be considered as being useful for the purpose of generating hypothesis rather than for that of obtaining solid evidence for the impact of climatic factors on vital rates. (author)

  19. Constrained consequence

    CSIR Research Space (South Africa)

    Britz, K

    2011-09-01

    Full Text Available their basic properties and relationship. In Section 3 we present a modal instance of these constructions which also illustrates with an example how to reason abductively with constrained entailment in a causal or action oriented context. In Section 4 we... of models with the former approach, whereas in Section 3.3 we give an example illustrating ways in which C can be de ned with both. Here we employ the following versions of local consequence: De nition 3.4. Given a model M = hW;R;Vi and formulas...

  20. Education Reform in Hong Kong: The ``Through-Road'' Model and its Societal Consequences

    Science.gov (United States)

    Poon, Anita Y. K.; Wong, Yiu-Chung

    2008-01-01

    Although Hong Kong's education system has long been criticized as lacking in creativity and over-emphasising rote learning, on the whole it has served Hong Kong well in the past years, breeding outstanding business, academic and political leaders who continue to maintain Hong Kong's competitive edge. The traditional elite schools have played a crucial role in the process. The education reform, which is still on-going, aims to overhaul the entire system by introducing the "through-road" model. To accomplish this, some mechanisms need to be changed. J.P. Farrell's concepts of equality and equity, C.W. Mills' concept of elitism, and P. Bourdieu and J. Coleman's concepts of cultural and social capital will be applied to analyse the consequences of the reform. The paper argues that the education reform may be well-intentioned in eliminating some elements of inequality and inequity in education, but that this comes at the expense of Hong Kong's cultural and social capital and leads to the development of new forms of inequality.

  1. The several faces of fear: ecological consequences of predation risk in a lagoon model system

    Directory of Open Access Journals (Sweden)

    Rafael Dettogni Guariento

    Full Text Available AIM: The aim of this study was to evaluate the role of predation risk on the occurrence of trophic cascades in a benthic food chain, and detect if the ecological consequences of predation risk can reverberate in patterns observed across different hierarchical scales, such as prey size, prey growth efficiency and nutrient recycling patterns. METHODS: The model system used in the present experiment consisted of a simple linear food chain comprising a predator, a consumer and periphyton as basal resources. For 2 weeks, we manipulated predation risk using caged predators, incapable of killing their prey, across twelve outdoor mesocosms, simulating natural lagoon conditions. RESULTS: Our results showed that predation risk can be responsible for the occurrence of a trophic cascade and the strength of the cascade is proportional to the intensity of risk. Predation risk can also negatively influence prey biomass and growth efficiency as well as affect nutrient recycling patterns by altering prey nutrient excretion rates. Through a simple mathematical formulation, we attempted to show that individual-level experimental results can be generalized to natural populations if evolutionary constraints to prey fitness can be reproduced in experimental conditions. CONCLUSIONS: Our results corroborate to integrate ecosystem dynamics with animal behavior, highlighting that not only bottom-up but also top-down mechanisms are responsible for determining ecosystem properties. We ultimately claim that prey adaptive foraging may serve to integrate ecosystem and evolutionary ecology, resulting in the development of a more robust and predictive theory of the functioning of aquatic ecosystems.

  2. Possible consequences of increasing life expectancy in Brazil: the perspective of a European historical demographer Possíveis conseqüências da crescente longevidade no Brasil: perspectiva de um demógrafo

    Directory of Open Access Journals (Sweden)

    Arthur E. Imhof

    1987-10-01

    Full Text Available Those over sixty years of age accounted for 6.6% of the total population of Brazil in 1985, in the Federal Republic of Germany this proportion was 20.3% in 1984. As early as 1950 it had been 14.5%. This proportion will not even be reached in Brazil in the year 2000 when persons aged sixty years and older are only projected to make up 8.8% of the total population. Similarly, in 1982/84 life expectancy at birth in the Federal Republic was 70.8 years for men and 77.5 for women; in Brazil the figures for 1980/85 were, by contrast, "only" 61.0 and 66.0. Against this background it is easy to understand why the discussion concerning an ageing society with its many related medical, economic, individual and social problems has been so slow in coming into its own in Brazil. As important as a more intensive consideration of these aspects may be in Brazil at present, they are, nevertheless, only one side of the story. For a European historical demographer with a long-term perspective of three of four hundred years, the other side of the story is just as important. The life expectancy which is almost ten years lower in Brazil is not a result of the fact that no one in Brazil lives to old age. In 1981 people sixty-five years and older accounted for 34.4% of all deaths! At the same time infants accounted for only 22.1% of total mortality. They are responsible, along with the "premature" deaths among youths and adults, for the low, "average" life expectancy figure. In Europe, by contrast, these "premature" deaths no longer play much of a role. In 1982/84 more than half of the women (52.8% in the Federal Republic of Germany lived to see their eightieth birthdays and almost half of the men (47.3% lived to see their seventy-fifth. Our biological existence is guaranteed to an extent today that would have been unthinkable a few generations ago. Then, the classic troika of "plague, hunger and war" threatened our forefathers all the time and everywhere. The radical

  3. Smoker-free workplace policies: developing a model of public health consequences of workplace policies barring employment to smokers.

    Science.gov (United States)

    Houle, B; Siegel, M

    2009-02-01

    A marked shift in tobacco-related workplace health promotion intervention involves the adoption of policies barring employment to smokers. We discuss the potential public health consequences of these policies on those affected-smokers, their families, the surrounding community and society at large. We find a lack of published evidence evaluating the effectiveness and consequences of these policies. By developing a model of policy effects, we outline possible unintended consequences. With such large gaps in the evidence base and the potential for deleterious consequences, we argue for increased discussion about the use of smoker-free employment policies as a public health intervention and for increased engagement of employers by the public health community in worksite health promotion.

  4. Increased Foraging in Outdoor Organic Pig Production—Modeling Environmental Consequences

    Directory of Open Access Journals (Sweden)

    Malene Jakobsen

    2015-11-01

    Full Text Available Consumers’ motivations for buying organic products include a wish of acquiring healthy, environmentally friendly products from production systems that also ensure a high level of animal welfare. However, the current Danish organic pig production faces important challenges regarding environmental impact of the system. High ammonia emissions arise from outdoor concrete areas with growing pigs and sows on pasture possess an increased risk of nitrogen (N leaching. Direct foraging in the range area is suggested as a way to improve the nutrient efficiency at farm level and to support a more natural behavior of the pig. Thus, by modeling, we investigated the environmental consequences of two alternative scenarios with growing pigs foraging in the range area and different levels of crops available for foraging—grass–clover or a combination of Jerusalem artichokes and lucerne. It was possible to have growing pigs on free-range without increasing N leaching compared to the current practice. The alternative system with Jerusalem artichokes and lucerne (high integration of forage showed the lowest carbon foot print with 3.12 CO2 eq kg−1 live weight pig compared to the current Danish pasture based system with 3.69 kg CO2 eq kg−1 live weight pig. Due to positive impact on soil carbon sequestration, the second alternative system based on grass-clover (low integration of forage showed a similar carbon foot print compared to current practice with 3.68 kg CO2 eq kg−1 live weight pig. It is concluded that in practice there is room for development of organic farming systems where direct foraging plays a central role.

  5. A sandpile model of grain blocking and consequences for sediment dynamics in step-pool streams

    Science.gov (United States)

    Molnar, P.

    2012-04-01

    variability in the system response by the processes of grain blocking and step collapse. The temporal correlation in input and output rates and the number of grains stored in the system at any given time are quantified by spectral analysis and statistics of long-range dependence. Although the model is only conceptually conceived to represent the real processes of step formation and collapse, connections will be made between the modelling results and some field and laboratory data on step-pool systems. The main focus in the discussion will be to demonstrate how even in such a simple model the processes of grain blocking and step collapse may impact the sediment transport rates to the point that certain changes in input are not visible anymore, along the lines of "shredding the signals" proposed by Jerolmack and Paola (2010). The consequences are that the notions of stability and equilibrium, the attribution of cause and effect, and the timescales of process and form in step-pool systems, and perhaps in many other fluvial systems, may have very limited applicability.

  6. Disease susceptibiliy in the zig-zag model of host-microbe Interactions: only a consequence of immune suppression?

    OpenAIRE

    Keller, Harald; Boyer, Laurent; Abad, Pierre

    2016-01-01

    For almost ten years, the Zig-Zag model has provided a convenient framework for explaining the molecular bases of compatibility and incompatibility in plant-microbe interactions (Jones and Dangl, 2006). According to the Zig-Zag model, disease susceptibility is a consequence of the suppression of host immunity during the evolutionary arms race between plants and pathogens. The Zig-Zag model thus fits well with biotrophic interactions, but is less applicable to interactions involving pathogens ...

  7. The impact of the demographic transition on dengue in Thailand: insights from a statistical analysis and mathematical modeling.

    Directory of Open Access Journals (Sweden)

    Derek A T Cummings

    2009-09-01

    Full Text Available An increase in the average age of dengue hemorrhagic fever (DHF cases has been reported in Thailand. The cause of this increase is not known. Possible explanations include a reduction in transmission due to declining mosquito populations, declining contact between human and mosquito, and changes in reporting. We propose that a demographic shift toward lower birth and death rates has reduced dengue transmission and lengthened the interval between large epidemics.Using data from each of the 72 provinces of Thailand, we looked for associations between force of infection (a measure of hazard, defined as the rate per capita at which susceptible individuals become infected and demographic and climactic variables. We estimated the force of infection from the age distribution of cases from 1985 to 2005. We find that the force of infection has declined by 2% each year since a peak in the late 1970s and early 1980s. Contrary to recent findings suggesting that the incidence of DHF has increased in Thailand, we find a small but statistically significant decline in DHF incidence since 1985 in a majority of provinces. The strongest predictor of the change in force of infection and the mean force of infection is the median age of the population. Using mathematical simulations of dengue transmission we show that a reduced birth rate and a shift in the population's age structure can explain the shift in the age distribution of cases, reduction of the force of infection, and increase in the periodicity of multiannual oscillations of DHF incidence in the absence of other changes.Lower birth and death rates decrease the flow of susceptible individuals into the population and increase the longevity of immune individuals. The increase in the proportion of the population that is immune increases the likelihood that an infectious mosquito will feed on an immune individual, reducing the force of infection. Though the force of infection has decreased by half, we find

  8. Modelling population-level consequences of chronic external gamma irradiation in aquatic invertebrates under laboratory conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lance, Emilie [Laboratoire de modelisation pour l' expertise environnementale (LM2E) Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-ENV, SERIS, Cadarache (France); Alonzo, Frederic, E-mail: frederic.alonzo@irsn.fr [Laboratoire d' ecotoxicologie des radionucleides (LECO) Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-ENV, SERIS, Cadarache (France); Garcia-Sanchez, Laurent [Laboratoire de biogeochimie, biodisponibilite et transferts des radionucleides (L2BT) Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-ENV, SERIS, Cadarache (France); Beaugelin-Seiller, Karine; Garnier-Laplace, Jacqueline [Laboratoire de modelisation pour l' expertise environnementale (LM2E) Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-ENV, SERIS, Cadarache (France)

    2012-07-01

    We modelled population-level consequences of chronic external gamma irradiation in aquatic invertebrates under laboratory conditions. We used Leslie matrices to combine life-history characteristics (duration of life stages, survival and fecundity rates) and dose rate-response curves for hatching, survival and reproduction fitted on effect data from the FREDERICA database. Changes in net reproductive rate R{sub 0} (offspring per individual) and asymptotic population growth rate {lambda} (dimensionless) were calculated over a range of dose rates in two marine polychaetes (Neanthes arenaceodentata and Ophryotrocha diadema) and a freshwater gastropod (Physa heterostropha). Sensitivities in R{sub 0} and {lambda} to changes in life-history traits were analysed in each species. Results showed that fecundity has the strongest influence on R{sub 0}. A delay in age at first reproduction is most critical for {lambda} independent of the species. Fast growing species were proportionally more sensitive to changes in individual endpoints than slow growing species. Reduction of 10% in population {lambda} were predicted at dose rates of 6918, 5012 and 74,131 {mu}Gy{center_dot}h{sup -1} in N. arenaceodentata, O. diadema and P. heterostropha respectively, resulting from a combination of strong effects on several individual endpoints in each species. These observations made 10%-reduction in {lambda} a poor criterion for population protection. The lowest significant changes in R{sub 0} and {lambda} were respectively predicted at a same dose rate of 1412 {mu}Gy h{sup -1} in N. arenaceodentata, at 760 and 716 {mu}Gy h{sup -1} in O. diadema and at 12,767 and 13,759 {mu}Gy h{sup -1} in P. heterostropha. These values resulted from a combination of slight but significant changes in several measured endpoints and were lower than effective dose rates calculated for the individual level in O. diadema and P. heterostropha. The relevance of the experimental dataset (external irradiation rather

  9. The application of the health effects models to the severe accident consequence analysis of nuclear power plants

    International Nuclear Information System (INIS)

    Yang Ling; Yeung, M.R.

    1998-01-01

    Health Effect Model (HEM) is an important model used in the analysis of severe accidents consequence of the Nuclear Power Plants (NPP). The accuracy of HEM affects the reliability of the assessment for the accidents consequences, and furthermore, the effectiveness of the emergency countermeasures taken for the health protection of the public around the NPPs. Based on the NUREG/CR4214 series reports, the paper sets appropriate parameters for HEM by studying both early and late HEMs used for domestic NPP accident consequence analysis. In the study, the Guangdong Daya Bay NPP is chosen as an example study to calculate the health risk of the Hong Kong population caused by Daya Bay NPP

  10. Forcing of global ocean models using an atmospheric boundary layer model: assessing consequences for the simulation of the AMOC

    Science.gov (United States)

    Abel, Rafael; Boening, Claus

    2015-04-01

    Current practice in the atmospheric forcing of ocean model simulations can lead to unphysical behaviours. The problem lies in the bulk formulation of the turbulent air-sea fluxes in conjunction with a prescribed, and unresponsive, atmospheric state as given, e.g., by reanalysis products. This forcing formulation corresponds to assuming an atmosphere with infinite heat capacity, and effectively damps SST anomalies even on basin scales. It thus curtails an important negative feedback between meridional ocean heat transport and SST in the North Atlantic, rendering simulations of the AMOC in such models excessively sensitive to details in the freshwater fluxes. As a consequence, such simulations are known for spurious drift behaviors which can only partially controlled by introducing some (and sometimes strong) unphysical restoring of sea surface salinity. There have been several suggestions during the last 20 years for at least partially alleviating the problem by including some simplified model of the atmospheric boundary layer (AML) which allows a feedback of SST anomalies on the near-surface air temperature and humidity needed to calculate the surface fluxes. We here present simulations with a simple, only thermally active AML formulation (based on the 'CheapAML' proposed by Deremble et al., 2013) implemented in a global model configuration based on NEMO (ORCA05). In a suite of experiments building on the CORE-bulk forcing methodology, we examine some general features of the AML-solutions (in which only the winds are prescribed) in comparison to solutions with a prescribed atmosperic state. The focus is on the North Atlantic, where we find that the adaptation of the atmospheric temperature the simulated ocean state can lead to strong local modifications in the surface heat fluxes in frontal regions (e.g., the 'Northwest Corner'). We particularly assess the potential of the AML-forcing concept for obtaining AMOC-simulations with reduced spurious drift, without

  11. Demographic faultlines: a meta-analysis of the literature.

    Science.gov (United States)

    Thatcher, Sherry M B; Patel, Pankaj C

    2011-11-01

    We propose and test a theoretical model focusing on antecedents and consequences of demographic faultlines. We also posit contingencies that affect overall team dynamics in the context of demographic faultlines, such as the study setting and performance measurement. Using meta-analysis structural equation modeling with a final data set consisting of 311 data points (i.e., k [predictor-criterion relationships]), from 39 studies that were obtained from 36 papers with a total sample size of 24,388 individuals in 4,366 teams, we found that sex and racial diversity increased demographic faultline strength more than did diversity on the attributes of functional background, educational background, age, and tenure. Demographic faultline strength was found to increase task and relationship conflict as well as decrease team cohesion. Furthermore, although demographic faultline strength decreased both team satisfaction and team performance, there was a stronger decrease in team performance than in team satisfaction. The strength of these relationships increased when the study was conducted in the lab rather than in the field. We describe the theoretical and practical implications of these findings for advancing the study of faultlines. (c) 2011 APA, all rights reserved.

  12. Antecedents and Consequences of Individual Performance Analysis of Turnover Intention Model (Empirical Study of Public Accountants in Indonesia)

    OpenAIRE

    Raza, Hendra; Maksum, Azhar; Erlina; Lumban Raja, Prihatin

    2014-01-01

    Azhar Maksum This study aims to examine empirically the antecedents of individual performance on its consequences of turnover intention in public accounting firms. There are eight variables measured which consists of auditors' empowerment, innovation professionalism, role ambiguity, role conflict, organizational commitment, individual performance and turnover intention. Data analysis is based on 163 public accountant using the Structural Equation Modeling assisted with an appli...

  13. International conference and workshop on modeling and mitigating the consequences of accidental releases of hazardous materials

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    This conference was held September 26--29, 1995 in New Orleans, Louisiana. The purpose of this conference was to provide a multidisciplinary forum for exchange of state-of-the-art information on the consequences of accidental releases of hazardous materials. Attention is focused on air dispersion of vapors. Individual papers have been processed separately for inclusion in the appropriate data bases

  14. Beyond the Situational Model: Bystander Action Consequences to Intervening in Situations Involving Sexual Violence.

    Science.gov (United States)

    Moschella, Elizabeth A; Bennett, Sidney; Banyard, Victoria L

    2016-03-02

    Sexual violence is a widely reported problem in college communities. To date, research has largely focused on bystander intervention as one way to help prevent this problem. Although perceived consequences of bystander intervention, such as the weighting of costs and benefits, have been examined, little research has explored what happens after a bystander intervenes. The current study investigated what bystanders report as perceived outcomes and actual consequences of their bystander actions in response to risk for sexual assault. Of the 545 surveyed, 150 reported having taking bystander action in the past month and qualitatively described their bystander behavior and the responses of those parties involved. A range of behavioral responses and intervention methods were identified. The most frequent responses reported by participants were victims conveying positive and perpetrators conveying negative responses. Different types of helping were associated with bystanders reporting different types of responses to their actions. Future research should incorporate additional measures of consequences of bystander intervention. Implications for policy and bystander intervention programs are discussed, stressing the need for bystander intervention programs to address a range of bystander behaviors and explain the potential consequences and risks of intervening. © The Author(s) 2016.

  15. Assessing the roles of impulsivity, food-related cognitions, BMI, and demographics in the dual pathway model of binge eating among men and women.

    Science.gov (United States)

    Mason, Tyler B; Lewis, Robin J

    2015-08-01

    The dual pathway model is a widely accepted model of binge eating that focuses on the role of sociocultural factors, negative affect, and dietary restraint. However, less is known about demographic (e.g., gender and ethnicity) differences in the model and the role of other variables in the model. To further our understanding of the dual pathway model of binge eating, the current study examined the role of demographics (i.e., gender, race, BMI, parental education and obesity), impulsivity, and food-related cognitions in the dual pathway model. A sample of college students completed a battery of measures. Multi-group structural equation modeling was used to evaluate the dual pathway model separately for men and women. Results supported the dual pathway model of binge eating among men and women, and also supported food-related cognitions as an important variable prior to binge eating. In other words, body shame was associated with more dietary restraint and negative affect, and in turn, dietary restraint and negative affect were associated with increased negative food-related cognitions. Then, food-related cognitions predicted binge eating. Additionally impulsivity was related to body shame, negative affect, and food-related cognitions, but was unrelated to binge eating after controlling for the other variables. Racial differences existed among women in BMI and body shame, but there were no racial differences among men. Our results suggest that the dual pathway model adequately explains binge eating among men and women, but that food-related cognitions may be an imporant anteceden to binge eating. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Physiological consequences of CPAP therapy withdrawal in patients with obstructive sleep apnoea-an opportunity for an efficient experimental model.

    Science.gov (United States)

    Schwarz, Esther I; Stradling, John R; Kohler, Malcolm

    2018-01-01

    Randomised controlled trials (RCTs) of continuous positive airway pressure (CPAP) in obstructive sleep apnoea (OSA) are time consuming, and their findings often inconclusive or limited due to suboptimal CPAP adherence in CPAP-naïve patients with OSA. Short-term CPAP withdrawal in patients with prior optimal CPAP adherence results in recurrence of OSA and its consequences. Thus, this experimental model serves as an efficient tool to investigate both the consequences of untreated OSA, and potential treatment alternatives to CPAP. The CPAP withdrawal protocol has been thoroughly validated, and applied in several RCTs focusing on cardiovascular and metabolic consequences of untreated OSA, as well as the assessment of treatment alternatives to CPAP.

  17. Physiological consequences of CPAP therapy withdrawal in patients with obstructive sleep apnoea—an opportunity for an efficient experimental model

    Science.gov (United States)

    Stradling, John R.; Kohler, Malcolm

    2018-01-01

    Randomised controlled trials (RCTs) of continuous positive airway pressure (CPAP) in obstructive sleep apnoea (OSA) are time consuming, and their findings often inconclusive or limited due to suboptimal CPAP adherence in CPAP-naïve patients with OSA. Short-term CPAP withdrawal in patients with prior optimal CPAP adherence results in recurrence of OSA and its consequences. Thus, this experimental model serves as an efficient tool to investigate both the consequences of untreated OSA, and potential treatment alternatives to CPAP. The CPAP withdrawal protocol has been thoroughly validated, and applied in several RCTs focusing on cardiovascular and metabolic consequences of untreated OSA, as well as the assessment of treatment alternatives to CPAP. PMID:29445525

  18. Research Note: The consequences of different methods for handling missing network data in Stochastic Actor Based Models.

    Science.gov (United States)

    Hipp, John R; Wang, Cheng; Butts, Carter T; Jose, Rupa; Lakon, Cynthia M

    2015-05-01

    Although stochastic actor based models (e.g., as implemented in the SIENA software program) are growing in popularity as a technique for estimating longitudinal network data, a relatively understudied issue is the consequence of missing network data for longitudinal analysis. We explore this issue in our research note by utilizing data from four schools in an existing dataset (the AddHealth dataset) over three time points, assessing the substantive consequences of using four different strategies for addressing missing network data. The results indicate that whereas some measures in such models are estimated relatively robustly regardless of the strategy chosen for addressing missing network data, some of the substantive conclusions will differ based on the missing data strategy chosen. These results have important implications for this burgeoning applied research area, implying that researchers should more carefully consider how they address missing data when estimating such models.

  19. System dynamics to model the unintended consequences of denying payment for venous thromboembolism after total knee arthroplasty.

    Science.gov (United States)

    Worni, Mathias; Pietrobon, Ricardo; Zammar, Guilherme Roberto; Shah, Jatin; Yoo, Bryan; Maldonato, Mauro; Takemoto, Steven; Vail, Thomas P

    2012-01-01

    The Hospital Acquired Condition Strategy (HACS) denies payment for venous thromboembolism (VTE) after total knee arthroplasty (TKA). The intention is to reduce complications and associated costs, while improving the quality of care by mandating VTE prophylaxis. We applied a system dynamics model to estimate the impact of HACS on VTE rates, and potential unintended consequences such as increased rates of bleeding and infection and decreased access for patients who might benefit from TKA. The system dynamics model uses a series of patient stocks including the number needing TKA, deemed ineligible, receiving TKA, and harmed due to surgical complication. The flow of patients between stocks is determined by a series of causal elements such as rates of exclusion, surgery and complications. The number of patients harmed due to VTE, bleeding or exclusion were modeled by year by comparing patient stocks that results in scenarios with and without HACS. The percentage of TKA patients experiencing VTE decreased approximately 3-fold with HACS. This decrease in VTE was offset by an increased rate of bleeding and infection. Moreover, results from the model suggest HACS could exclude 1.5% or half a million patients who might benefit from knee replacement through 2020. System dynamics modeling indicates HACS will have the intended consequence of reducing VTE rates. However, an unintended consequence of the policy might be increased potential harm resulting from over administration of prophylaxis, as well as exclusion of a large population of patients who might benefit from TKA.

  20. System Dynamics to Model the Unintended Consequences of Denying Payment for Venous Thromboembolism after Total Knee Arthroplasty

    Science.gov (United States)

    Worni, Mathias; Pietrobon, Ricardo; Zammar, Guilherme Roberto; Shah, Jatin; Yoo, Bryan; Maldonato, Mauro; Takemoto, Steven; Vail, Thomas P.

    2012-01-01

    Background The Hospital Acquired Condition Strategy (HACS) denies payment for venous thromboembolism (VTE) after total knee arthroplasty (TKA). The intention is to reduce complications and associated costs, while improving the quality of care by mandating VTE prophylaxis. We applied a system dynamics model to estimate the impact of HACS on VTE rates, and potential unintended consequences such as increased rates of bleeding and infection and decreased access for patients who might benefit from TKA. Methods and Findings The system dynamics model uses a series of patient stocks including the number needing TKA, deemed ineligible, receiving TKA, and harmed due to surgical complication. The flow of patients between stocks is determined by a series of causal elements such as rates of exclusion, surgery and complications. The number of patients harmed due to VTE, bleeding or exclusion were modeled by year by comparing patient stocks that results in scenarios with and without HACS. The percentage of TKA patients experiencing VTE decreased approximately 3-fold with HACS. This decrease in VTE was offset by an increased rate of bleeding and infection. Moreover, results from the model suggest HACS could exclude 1.5% or half a million patients who might benefit from knee replacement through 2020. Conclusion System dynamics modeling indicates HACS will have the intended consequence of reducing VTE rates. However, an unintended consequence of the policy might be increased potential harm resulting from over administration of prophylaxis, as well as exclusion of a large population of patients who might benefit from TKA. PMID:22536313

  1. Models and methods to evaluate consequences of the release of airborne radioactivity from NNPs

    International Nuclear Information System (INIS)

    Anh, T.H.

    1989-01-01

    To examine the radioactive contamination and possible consequences of a nuclear power plant on living organisms during its operation periodes, the computer programmes were elaborated for assessing its fluences on the environment. The authors have resolved the following problems: i) Calculation of fission product inventories in the reactor core; ii) Calculation of the atmospheric dispersion of the released radionuclides under the meteorological conditions as well as the deposition of the radioactive substances on the soil; iii) Calculation of the irradiation doses

  2. Using experiments and demographic models to assess rare plant vulnerability to utlity-scale solar energy development

    Science.gov (United States)

    Moore, K. A.

    2015-12-01

    Pressing challenges for the implementation of solar energy are the effects of construction and operation on protected animal and plant species. Siting and mitigation of solar energy often requires understanding of basic biology and distributions of rare species that are unknown. How can we rapidly collect the information necessary on species- and site-specific population dynamics to effectively design mitigation and conservation measures? We have developed an integrated approach to assessing the vulnerability of a suite of representative rare plant species in the region. We implemented a prioritized series of demographic and experimental studies over the past four years to identify the types of species, populations, and life stages most vulnerable to impact or prone to conservation efforts. We have found substantial variation in vegetative and sexual reproduction between study populations for several rare plants, including between populations that vary in putative impact by development and/or effects of experimental solar arrays. For a subset of species, we designed population viability analysis and applied them to identify sensitive vital rates and compare quasi-extinction probabilities under different climate and impact scenarios. By utilizing practical experiments to test for the effects of real or simulated impacts, we found differences in vital rates between natural and disturbed populations adjacent to and within solar installations. We draw conclusions from our work to guide the analysis of benefits, permitting, and design of utility-scale solar energy facilities.

  3. Risk adjustment models for interhospital comparison of CS rates using Robson's ten group classification system and other socio-demographic and clinical variables.

    Science.gov (United States)

    Colais, Paola; Fantini, Maria P; Fusco, Danilo; Carretta, Elisa; Stivanello, Elisa; Lenzi, Jacopo; Pieri, Giulia; Perucci, Carlo A

    2012-06-21

    Caesarean section (CS) rate is a quality of health care indicator frequently used at national and international level. The aim of this study was to assess whether adjustment for Robson's Ten Group Classification System (TGCS), and clinical and socio-demographic variables of the mother and the fetus is necessary for inter-hospital comparisons of CS rates. The study population includes 64,423 deliveries in Emilia-Romagna between January 1, 2003 and December 31, 2004, classified according to theTGCS. Poisson regression was used to estimate crude and adjusted hospital relative risks of CS compared to a reference category. Analyses were carried out in the overall population and separately according to the Robson groups (groups I, II, III, IV and V-X combined). Adjusted relative risks (RR) of CS were estimated using two risk-adjustment models; the first (M1) including the TGCS group as the only adjustment factor; the second (M2) including in addition demographic and clinical confounders identified using a stepwise selection procedure. Percentage variations between crude and adjusted RRs by hospital were calculated to evaluate the confounding effect of covariates. The percentage variations from crude to adjusted RR proved to be similar in M1 and M2 model. However, stratified analyses by Robson's classification groups showed that residual confounding for clinical and demographic variables was present in groups I (nulliparous, single, cephalic, ≥37 weeks, spontaneous labour) and III (multiparous, excluding previous CS, single, cephalic, ≥37 weeks, spontaneous labour) and IV (multiparous, excluding previous CS, single, cephalic, ≥37 weeks, induced or CS before labour) and to a minor extent in groups II (nulliparous, single, cephalic, ≥37 weeks, induced or CS before labour) and IV (multiparous, excluding previous CS, single, cephalic, ≥37 weeks, induced or CS before labour). The TGCS classification is useful for inter-hospital comparison of CS section rates, but

  4. Severe accident modeling and offsite dose consequence evaluations for nuclear power plant emergency planning

    Energy Technology Data Exchange (ETDEWEB)

    Chen, S.H.; Feng, T.S.; Huang, K.C. [National Tsing-Hua Univ., Hsinchu, Taiwan (China); Wang, J.R. [Inst. of Nuclear Energy Research, Longtan, Taiwan (China); Cheng, Y.H. [Industrial Tech. Res. Inst., Hsinchu, Taiwan (China); Shih, C., E-mail: ckshih@ess.nthu.edu.tw [National Tsing-Hua Univ., Hsinchu, Taiwan (China)

    2011-07-01

    We have investigated the roles of Firewater Addition System and Passive Flooder in ABWR severe accidents, such as LOCA and SBO. The results are apparent that Firewater System is vital in the highly unlikely situation where all AC are lost. Also in this paper, we present EPZDose, an effective and faster-than-real time code for offsite dose consequences predictions and evaluations. Illustrations with the release from our severe accident scenario show friendly and informative user's interface for supporting decision makings in nuclear emergency situations. (author)

  5. Modeling the consequences of hypothetical accidents for the Titan II system

    International Nuclear Information System (INIS)

    Greenly, G.D.; Sullivan, T.J.

    1981-11-01

    Calculations have been made with the Atmospheric Release Advisory Capability (ARAC) suite of three-dimensional transport and diffusion codes MATHEW/ADPIC to assess the consequences of severe, hypothetical accident scenarios. One set of calculations develops the integrated dose and surface deposition patterns for a non-nuclear, high explosive detonation and dispersal of material. A second set of calculations depicts the time integrated dose and instantaneous concentration patterns for a substantial, continuous leak of the missile fuel oxidizer converted to nitrogen dioxide (NO 2 ). The areas affected and some of the implications for emergency response management are discussed

  6. RASCAL [Radiological Assessment System for Consequence AnaLysis]: A screening model for estimating doses from radiological accidents

    International Nuclear Information System (INIS)

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

    1988-01-01

    The Radiological Assessment System for Consequence AnaLysis (RASCAL) is a new MS-DOS-based dose assessment model which has been written for the US Nuclear Regulatory Commission for use during response to radiological emergencies. RASCAL is designed to provide crude estimates of the effects of an accident while the accident is in progress and only limited information is available. It has been designed to be very simple to use and to run quickly. RASCAL is unique in that it estimates the source term based on fundamental plant conditions and does not rely solely on release rate estimation (e.g., Ci/sec of I-131). Therefore, it can estimate consequences of accidents involving unmonitored pathways or projected failures. RASCAL will replace the older model, IRDAM. 6 refs

  7. Use of principal components analysis and three-dimensional atmospheric-transport models for reactor-consequence evaluation

    International Nuclear Information System (INIS)

    Gudiksen, P.H.; Walton, J.J.; Alpert, D.J.; Johnson, J.D.

    1982-01-01

    This work explores the use of principal components analysis coupled to three-dimensional atmospheric transport and dispersion models for evaluating the environmental consequences of reactor accidents. This permits the inclusion of meteorological data from multiple sites and the effects of topography in the consequence evaluation; features not normally included in such analyses. The technique identifies prevailing regional wind patterns and their frequencies for use in the transport and dispersion calculations. Analysis of a hypothetical accident scenario involving a release of radioactivity from a reactor situated in a river valley indicated the technique is quite useful whenever recurring wind patterns exist, as is often the case in complex terrain situations. Considerable differences were revealed in a comparison with results obtained from a more conventional Gaussian plume model using only the reactor site meteorology and no topographic effects

  8. Modelling changes to electricity demand load duration curves as a consequence of predicted climate change for Australia

    International Nuclear Information System (INIS)

    Thatcher, Marcus J.

    2007-01-01

    In this paper, we describe a method for constructing regional electricity demand data sets at 30 min intervals, which are consistent with climate change scenarios. Specifically, we modify a commonly used linear regression model between regional electricity demand and climate to also describe intraday variability in demand so that regional load duration curves (LDCs) can be predicted. The model is evaluated for four different Australian states that are participants in the Australian National Electricity Market (NEM) and the resultant data sets are found to reproduce each state's LDCs with reasonable accuracy. We also apply the demand model to CSIRO's Mk 3 global climate model data sets that have been downscaled to 60 km resolution using CSIRO's conformal-cubic atmospheric model to estimate how LDCs change as a consequence of a 1 C increase in the average temperature of Australian state capital cities. These regional electricity demand data sets are then useful for economic modelling of electricity markets such as the NEM. (author)

  9. Parameterization of the driving time in the evacuation or fast relocation model of an accident consequence code

    International Nuclear Information System (INIS)

    Pfeffer, W.; Hofer, E.; Nowak, E.; Schnadt, H.

    1988-01-01

    The model of protective measures in the accident consequence code system UFOMOD of the German Risk Study, Phase B, requires the driving times of the population to be evacuated for the evaluation of the dose received during the evacuation. The parameter values are derived from evacuation simulations carried out with the code EVAS for 36 sectors from various sites. The simulations indicated that the driving time strongly depends on the population density, whereas other influences are less important. It was decided to use different driving times in the consequence code for each of four population density classes as well as for each of three or four fractions of the population in a sector. The variability between sectors of a class was estimated from the 36 sectors, in order to derive subjective probability distributions that are to model the uncertainty in the parameter value to be used for any of the fractions in a particular sector for which an EVAS simulation has not yet been performed. To this end also the impact of the uncertainties in the parameters and modelling assumptions of EVAS on the simulated times was quantified using expert judgement. The distributions permit the derivation of a set of driving times to be used as so-called ''best estimate'' or reference values in the accident consequence code. Additionally they are directly applicable in an uncertainty and sensitivity analysis

  10. Health effects models for off-site radiological consequence analysis of nuclear reactor accidents

    International Nuclear Information System (INIS)

    Togawa, Orihiko; Homma, Toshimitsu; Matsuzuru, Hideo; Kobayashi, Sadayoshi

    1991-02-01

    A first version of models has been developed for predicting the number of occurrences of health effects induced by radiation exposure in nuclear reactor accidents. The models are based on the health effects models developed originally by Harvard University (NUREG/CR-4214). These models are revised on the basis of the new information on risk estimates by the reassessment of the radiation dosimetry in Hiroshima and Nagasaki. The models deal with the following effects: (1) early effects models for bone marrow, lungs, gastrointestinal tract, central nervous system, thyroid, skin and reproductive organs, using the Weibull function, (2) late somatic effects models including leukemia and cancers of breast, lungs, thyroid, gastrointestinal tract and so forth, on the basis of the information derived from epidemiological studies on the atomic bomb survivors of Hiroshima and Nagasaki, (3) models for late and developmental effects due to exposure in utero. (author)

  11. Dancing with Demographers.

    Science.gov (United States)

    Robertson, Heather-Jane

    2000-01-01

    Demographic projections concerning the shortage of teachers in Canada, their pay scale, the feminization of teaching, the gender gap in salaries, and teacher autonomy have often been incorrect, or correct for the wrong reasons. Instead of relying on demographic predictions, teachers should contemplate who they really want to be professionally,…

  12. Fuels planning: science synthesis and integration; environmental consequences fact sheet 10: The Understory Response Model

    Science.gov (United States)

    Steve Sutherland; Melanie Miller

    2005-01-01

    The Understory Response Model is a species-specific computer model that qualitatively predicts change in total species biomass for grasses, forbs, and shrubs after thinning, prescribed fire, or wildfire. The model examines the effect of fuels management on plant survivorship and reproduction. This fact sheet identifies the intended users and uses, required inputs, what...

  13. Fuels planning: science synthesis and integration; environmental consequences fact sheet 11: Smoke Impact Spreadsheet (SIS) model

    Science.gov (United States)

    Trent Wickman; Ann Acheson

    2005-01-01

    The Smoke Impact Spreadsheet (SIS) is a simple-to-use planning model for calculating particulate matter (PM) emissions and concentrations downwind of wildland fires. This fact sheet identifies the intended users and uses, required inputs, what the model does and does not do, and tells the user how to obtain the model.

  14. Forecasting the consequences of accidental releases of radionuclides in the atmosphere from ensemble dispersion modelling

    International Nuclear Information System (INIS)

    Galmarini, S.; Bianconi, R.; Bellasio, R.; Graziani, G.

    2001-01-01

    The RTMOD system is presented as a tool for the intercomparison of long-range dispersion models as well as a system for support of decision making. RTMOD is an internet-based procedure that collects the results of more than 20 models used around the world to predict the transport and deposition of radioactive releases in the atmosphere. It allows the real-time acquisition of model results and their intercomparison. Taking advantage of the availability of several model results, the system can also be used as a tool to support decision making in case of emergency. The new concept of ensemble dispersion modelling is introduced which is the basis for the decision-making application of RTMOD. New statistical parameters are presented that allow gathering the results of several models to produce a single dispersion forecast. The devised parameters are presented and tested on the results of RTMOD exercises

  15. THE MODELING OF DRUG ADDICTION PREVALENCE AND ITS CONSEQUENCES IN RUSSIAN REGIONS

    Directory of Open Access Journals (Sweden)

    V.P. Sirotin

    2009-12-01

    Full Text Available The narcotization prevalence in Russia as whole and its regions is described. In order to provide the adequate models the clusters of regions on the level of their economic development are defined. For every group the regression model of drug addiction social distress is constructed. Modeling results allow to find the features of regions and the most significant factors determining the drug addiction prevalence.

  16. Long Wavelength SAR Backscatter Modelling Trends as a Consequence of the Emergent Properties of Tree Populations

    Directory of Open Access Journals (Sweden)

    Matthew Brolly

    2014-07-01

    Full Text Available This study describes the novel use of a macroecological plant and forest structure model in conjunction with a Radiative Transfer (RT model to better understand interactions between microwaves and forest canopies. Trends predicted by the RT model, resulting from interactions with mixed age, mono and multi species forests, are analysed in comparison to those predicted using a simplistic structure based scattering model. This model relates backscatter to scatterer cross sectional or volume specifications, dependent on the size. The Spatially Explicit Reiterative Algorithm (SERA model is used to provide a widely varied tree size distribution while maintaining allometric consistency to produce a natural-like forest representation. The RT model is parameterised using structural information from SERA and microwave backscatter simulations are used to analyse the impact of changes to the forest stand. Results show that the slope of the saturation curve observed in the Synthetic Aperture Radar (SAR backscatter-biomass relationship is sensitive to thinning and therefore forest basal area. Due to similarities displayed between the results of the RT and simplistic model, it is determined that forest SAR backscatter behaviour at long microwave wavelengths may be described generally using equations related to total stem volume and basal area. The nature of these equations is such that they describe saturating behaviour of forests in the absence of attenuation in comparable fashion to the trends exhibited using the RT model. Both modelled backscatter trends predict a   relationship to forest basal area from an early age when forest volume is increasing. When this is not the case, it is assumed to be a result of attenuation of the dominant stem-ground interaction due to the presence of excessive numbers of stems. This work shows how forest growth models can be successfully incorporated into existing independent scattering models and reveals, through the RT

  17. Demographic modelling reveals a history of divergence with gene flow for a glacially tied stonefly in a changing post-Pleistocene landscape

    Science.gov (United States)

    Hotaling, Scott; Muhlfeld, Clint C.; Giersch, J. Joseph; Ali, Omar; Jordan, Steve; Miller, Michael R.; Luikart, Gordon; Weisrock, David W.

    2018-01-01

    AimClimate warming is causing extensive loss of glaciers in mountainous regions, yet our understanding of how glacial recession influences evolutionary processes and genetic diversity is limited. Linking genetic structure with the influences shaping it can improve understanding of how species respond to environmental change. Here, we used genome-scale data and demographic modelling to resolve the evolutionary history of Lednia tumana, a rare, aquatic insect endemic to alpine streams. We also employed a range of widely used data filtering approaches to quantify how they influenced population structure results.LocationAlpine streams in the Rocky Mountains of Glacier National Park, Montana, USA.TaxonLednia tumana, a stonefly (Order Plecoptera) in the family Nemouridae.MethodsWe generated single nucleotide polymorphism data through restriction-site associated DNA sequencing to assess contemporary patterns of genetic structure for 11 L. tumana populations. Using identified clusters, we assessed demographic history through model selection and parameter estimation in a coalescent framework. During population structure analyses, we filtered our data to assess the influence of singletons, missing data and total number of markers on results.ResultsContemporary patterns of population structure indicate that L. tumana exhibits a pattern of isolation-by-distance among populations within three genetic clusters that align with geography. Mean pairwise genetic differentiation (FST) among populations was 0.033. Coalescent-based demographic modelling supported divergence with gene flow among genetic clusters since the end of the Pleistocene (~13-17 kya), likely reflecting the south-to-north recession of ice sheets that accumulated during the Wisconsin glaciation.Main conclusionsWe identified a link between glacial retreat, evolutionary history and patterns of genetic diversity for a range-restricted stonefly imperiled by climate change. This finding included a history of

  18. Do Insect Populations Die at Constant Rates as They Become Older? Contrasting Demographic Failure Kinetics with Respect to Temperature According to the Weibull Model.

    Directory of Open Access Journals (Sweden)

    Petros Damos

    Full Text Available Temperature implies contrasting biological causes of demographic aging in poikilotherms. In this work, we used the reliability theory to describe the consistency of mortality with age in moth populations and to show that differentiation in hazard rates is related to extrinsic environmental causes such as temperature. Moreover, experiments that manipulate extrinsic mortality were used to distinguish temperature-related death rates and the pertinence of the Weibull aging model. The Newton-Raphson optimization method was applied to calculate parameters for small samples of ages at death by estimating the maximum likelihoods surfaces using scored gradient vectors and the Hessian matrix. The study reveals for the first time that the Weibull function is able to describe contrasting biological causes of demographic aging for moth populations maintained at different temperature regimes. We demonstrate that at favourable conditions the insect death rate accelerates as age advances, in contrast to the extreme temperatures in which each individual drifts toward death in a linear fashion and has a constant chance of passing away. Moreover, slope of hazard rates shifts towards a constant initial rate which is a pattern demonstrated by systems which are not wearing out (e.g. non-aging since the failure, or death, is a random event independent of time. This finding may appear surprising, because, traditionally, it was mostly thought as rule that in aging population force of mortality increases exponentially until all individuals have died. Moreover, in relation to other studies, we have not observed any typical decelerating aging patterns at late life (mortality leveling-off, but rather, accelerated hazard rates at optimum temperatures and a stabilized increase at the extremes.In most cases, the increase in aging-related mortality was simulated reasonably well according to the Weibull survivorship model that is applied. Moreover, semi log- probability hazard

  19. A Population Consequence of Acoustic Disturbance Model for Cuviers beaked whale (Ziphius cavirostris) in Southern California

    Science.gov (United States)

    2015-09-30

    two sources. The energetics model that will underpin both PCoD models for Md and Zc has also been published (New et al 2013). The full PCoD model...to Zc on SCORE. We will also be able to use the simplified PCoD model for beaked whales currently being developed under the ONR-funded project...34Using an interim PCoD protocol to assess the effects of disturbance associated with US Navy exercises on marine mammal populations”. This project will

  20. Some consequences of a scale-breaking model in electron and neutrino deep inelastic scattering

    International Nuclear Information System (INIS)

    Fernandez Pacheco, A.; Grifols, J.A.; Schmidt, I.A.

    1978-01-01

    Electron and neutrino deep inelastic processes, extending a simple parton model explanation of the approach to scaling observed in electroproduction at large x are analyzed. The model is successful in fitting the present experimental data without any explicit effects from asymptotic freedom or new quarks. This model has a large q 2 behaviour which is quite different from that expected in asymptotic freedom (AF) theories and comparisons to data can be used to sharpen any experimental demonstration of AF effects. Of course, the model is consistent with AF and both effects could be present

  1. Practical examples of modeling choices and their consequences for risk assessment

    Science.gov (United States)

    Although benchmark dose (BMD) modeling has become the preferred approach to identifying a point of departure (POD) over the No Observed Adverse Effect Level, there remain challenges to its application in human health risk assessment. BMD modeling, as currently implemented by the...

  2. Radiological health effects models for nuclear power plant accident consequence analysis

    International Nuclear Information System (INIS)

    Evans, J.S.; Moeller, D.W.

    1989-01-01

    Improved health effects models have been developed for assessing the early effects, late somatic effects and genetic effects that might result from low-LET radiation exposures to populations following a major accident in a nuclear power plant. All the models have been developed in such a way that the dynamics of population risks can be analyzed. Estimates of life years lost and the duration of illnesses were generated and a framework recommended for summarizing health impacts. Uncertainty is addressed by providing models for upper, central and lower estimates of most effects. The models are believed to be a significant improvement over the models used in the U.S. Nuclear Regulatory Commission's Reactor Safety Study, and they can easily be modified to reflect advances in scientific understanding of the health effects of ionizing radiation

  3. Cost-effectiveness of embryo transfer strategies: a decision analytic model using long-term costs and consequences of singletons and multiples born as a consequence of IVF.

    Science.gov (United States)

    van Heesch, M M J; van Asselt, A D I; Evers, J L H; van der Hoeven, M A H B M; Dumoulin, J C M; van Beijsterveldt, C E M; Bonsel, G J; Dykgraaf, R H M; van Goudoever, J B; Koopman-Esseboom, C; Nelen, W L D M; Steiner, K; Tamminga, P; Tonch, N; Torrance, H L; Dirksen, C D

    2016-11-01

    What is the cost-effectiveness of elective single embryo transfer (eSET) versus double embryo transfer (DET) strategies from a societal perspective, when applying a time horizon of 1, 5 and 18 years? From a short-term perspective (1 year) it is cost-effective to replace DET with single embryo transfer; however when intermediate- (5 years) and long-term (18 years) costs and consequences are incorporated, DET becomes the most cost-effective strategy, given a ceiling ratio of €20 000 per quality-adjusted life years (QALY) gained. According to previous cost-effectiveness research into embryo transfer strategies, DET is considered cost-effective if society is willing to pay around €20 000 for an extra live birth. However, interpretation of those studies is complicated, as those studies fail to incorporate long-term costs and outcomes and used live birth as a measure of effectiveness instead of QALYs. With this outcome, both multiple and singletons were valued as one live birth, whereas costs of all children of a multiple were incorporated. A Markov model (cycle length: 1 year; time horizon: 1, 5 and 18 years) was developed comparing a maximum of: (i) three cycles of eSET in all patients; (ii) four cycles of eSET in all patients; (iii) five cycles of eSET in all patients; (iv) three cycles of standard treatment policy (STP), i.e. eSET in women costs were estimated for all comparators. Input parameters were derived from a retrospective cohort study, in which hospital resource data were collected (n=580) and a parental questionnaire was sent out (431 respondents). Probabilistic sensitivity analysis (5000 iterations) was performed. With a time horizon of 18 years, DETx3 is most effective (0.54 live births, 10.2 LYs and 9.8 QALYs) and expensive (€37 871) per couple starting IVF. Three cycles of eSET are least effective (0.43 live births, 7.1 LYs and 6.8 QALYs) and expensive (€25 563). We assumed that society is willing to pay €20 000 per QALY gained. With a time

  4. Age-specific distributions from coarse-count data: An epidemiological and demographic application of a penalized composite link model

    DEFF Research Database (Denmark)

    Rizzi, Silvia

    as realizations of a Poisson process. The latent unobserved distribution with higher resolution is assumed to be smooth and can be estimated from the composite data via maximum likelihood. In the second study the penalized composite link model for ungrouping is compared to alternative well known ungrouping...

  5. Indo-Pacific humpback dolphins (Sousa chinensis) in Hong Kong: Modelling demographic parameters with mark-recapture techniques.

    Science.gov (United States)

    Chan, Stephen C Y; Karczmarski, Leszek

    2017-01-01

    Indo-Pacific humpback dolphins (Sousa chinensis) inhabiting Hong Kong waters are thought to be among the world's most anthropogenically impacted coastal delphinids. We have conducted a 5-year (2010-2014) photo-ID study and performed the first in this region comprehensive mark-recapture analysis applying a suite of open population models and robust design models. Cormack-Jolly-Seber (CJS) models suggested a significant transient effect and seasonal variation in apparent survival probabilities as result of a fluid movement beyond the study area. Given the spatial restrictions of our study, limited by an administrative border, if emigration was to be considered negligible the estimated survival rate of adults was 0.980. Super-population estimates indicated that at least 368 dolphins used Hong Kong waters as part of their range. Closed robust design models suggested an influx of dolphins from winter to summer and increased site fidelity in summer; and outflux, although less prominent, during summer-winter intervals. Abundance estimates in summer (N = 144-231) were higher than that in winter (N = 87-111), corresponding to the availability of prey resources which in Hong Kong waters peaks during summer months. We point out that the current population monitoring strategy used by the Hong Kong authorities is ill-suited for a timely detection of a population change and should be revised.

  6. Indo-Pacific humpback dolphins (Sousa chinensis in Hong Kong: Modelling demographic parameters with mark-recapture techniques.

    Directory of Open Access Journals (Sweden)

    Stephen C Y Chan

    Full Text Available Indo-Pacific humpback dolphins (Sousa chinensis inhabiting Hong Kong waters are thought to be among the world's most anthropogenically impacted coastal delphinids. We have conducted a 5-year (2010-2014 photo-ID study and performed the first in this region comprehensive mark-recapture analysis applying a suite of open population models and robust design models. Cormack-Jolly-Seber (CJS models suggested a significant transient effect and seasonal variation in apparent survival probabilities as result of a fluid movement beyond the study area. Given the spatial restrictions of our study, limited by an administrative border, if emigration was to be considered negligible the estimated survival rate of adults was 0.980. Super-population estimates indicated that at least 368 dolphins used Hong Kong waters as part of their range. Closed robust design models suggested an influx of dolphins from winter to summer and increased site fidelity in summer; and outflux, although less prominent, during summer-winter intervals. Abundance estimates in summer (N = 144-231 were higher than that in winter (N = 87-111, corresponding to the availability of prey resources which in Hong Kong waters peaks during summer months. We point out that the current population monitoring strategy used by the Hong Kong authorities is ill-suited for a timely detection of a population change and should be revised.

  7. Demographic projection of high-elevation white pines infected with white pine blister rust: a nonlinear disease model

    Science.gov (United States)

    S. G. Field; A. W. Schoettle; J. G. Klutsch; S. J. Tavener; M. F. Antolin

    2012-01-01

    Matrix population models have long been used to examine and predict the fate of threatened populations. However, the majority of these efforts concentrate on long-term equilibrium dynamics of linear systems and their underlying assumptions and, therefore, omit the analysis of transience. Since management decisions are typically concerned with the short term (

  8. The macroeconomic consequences of renouncing to universal access to antiretroviral treatment for HIV in Africa: a micro-simulation model.

    Science.gov (United States)

    Ventelou, Bruno; Arrighi, Yves; Greener, Robert; Lamontagne, Erik; Carrieri, Patrizia; Moatti, Jean-Paul

    2012-01-01

    Previous economic literature on the cost-effectiveness of antiretroviral treatment (ART) programs has been mainly focused on the microeconomic consequences of alternative use of resources devoted to the fight against the HIV pandemic. We rather aim at forecasting the consequences of alternative scenarios for the macroeconomic performance of countries. We used a micro-simulation model based on individuals aged 15-49 selected from nationally representative surveys (DHS for Cameroon, Tanzania and Swaziland) to compare alternative scenarios : 1-freezing of ART programs to current levels of access, 2- universal access (scaling up to 100% coverage by 2015, with two variants defining ART eligibility according to previous or current WHO guidelines). We introduced an "artificial" ageing process by programming methods. Individuals could evolve through different health states: HIV negative, HIV positive (with different stages of the syndrome). Scenarios of ART procurement determine this dynamics. The macroeconomic impact is obtained using sample weights that take into account the resulting age-structure of the population in each scenario and modeling of the consequences on total growth of the economy. Increased levels of ART coverage result in decreasing HIV incidence and related mortality. Universal access to ART has a positive impact on workers' productivity; the evaluations performed for Swaziland and Cameroon show that universal access would imply net cost-savings at the scale of the society, when the full macroeconomic consequences are introduced in the calculations. In Tanzania, ART access programs imply a net cost for the economy, but 70% of costs are covered by GDP gains at the 2034 horizon, even in the extended coverage option promoted by WHO guidelines initiating ART at levels of 350 cc/mm(3) CD4 cell counts. Universal Access ART scaling-up strategies, which are more costly in the short term, remain the best economic choice in the long term. Renouncing or

  9. TU-C-12A-09: Modeling Pathologic Response of Locally Advanced Esophageal Cancer to Chemo-Radiotherapy Using Quantitative PET/CT Features, Clinical Parameters and Demographics

    International Nuclear Information System (INIS)

    Zhang, H; Chen, W; Kligerman, S; D’Souza, W; Suntharalingam, M; Lu, W; Tan, S; Kim, G

    2014-01-01

    Purpose: To develop predictive models using quantitative PET/CT features for the evaluation of tumor response to neoadjuvant chemo-radiotherapy (CRT) in patients with locally advanced esophageal cancer. Methods: This study included 20 patients who underwent tri-modality therapy (CRT + surgery) and had 18 F-FDG PET/CT scans before initiation of CRT and 4-6 weeks after completion of CRT but prior to surgery. Four groups of tumor features were examined: (1) conventional PET/CT response measures (SUVmax, tumor diameter, etc.); (2) clinical parameters (TNM stage, histology, etc.) and demographics; (3) spatial-temporal PET features, which characterize tumor SUV intensity distribution, spatial patterns, geometry, and associated changes resulting from CRT; and (4) all features combined. An optimal feature set was identified with recursive feature selection and cross-validations. Support vector machine (SVM) and logistic regression (LR) models were constructed for prediction of pathologic tumor response to CRT, using cross-validations to avoid model over-fitting. Prediction accuracy was assessed via area under the receiver operating characteristic curve (AUC), and precision was evaluated via confidence intervals (CIs) of AUC. Results: When applied to the 4 groups of tumor features, the LR model achieved AUCs (95% CI) of 0.57 (0.10), 0.73 (0.07), 0.90 (0.06), and 0.90 (0.06). The SVM model achieved AUCs (95% CI) of 0.56 (0.07), 0.60 (0.06), 0.94 (0.02), and 1.00 (no misclassifications). Using spatial-temporal PET features combined with conventional PET/CT measures and clinical parameters, the SVM model achieved very high accuracy (AUC 1.00) and precision (no misclassifications), significantly better than using conventional PET/CT measures or clinical parameters and demographics alone. For groups with a large number of tumor features (groups 3 and 4), the SVM model achieved significantly higher accuracy than the LR model. Conclusion: The SVM model using all features including

  10. Modeling Pathologic Response of Esophageal Cancer to Chemoradiation Therapy Using Spatial-Temporal 18F-FDG PET Features, Clinical Parameters, and Demographics

    International Nuclear Information System (INIS)

    Zhang, Hao; Tan, Shan; Chen, Wengen; Kligerman, Seth; Kim, Grace; D'Souza, Warren D.; Suntharalingam, Mohan; Lu, Wei

    2014-01-01

    Purpose: To construct predictive models using comprehensive tumor features for the evaluation of tumor response to neoadjuvant chemoradiation therapy (CRT) in patients with esophageal cancer. Methods and Materials: This study included 20 patients who underwent trimodality therapy (CRT + surgery) and underwent 18 F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) both before and after CRT. Four groups of tumor features were examined: (1) conventional PET/CT response measures (eg, standardized uptake value [SUV] max , tumor diameter); (2) clinical parameters (eg, TNM stage, histology) and demographics; (3) spatial-temporal PET features, which characterize tumor SUV intensity distribution, spatial patterns, geometry, and associated changes resulting from CRT; and (4) all features combined. An optimal feature set was identified with recursive feature selection and cross-validations. Support vector machine (SVM) and logistic regression (LR) models were constructed for prediction of pathologic tumor response to CRT, cross-validations being used to avoid model overfitting. Prediction accuracy was assessed by area under the receiver operating characteristic curve (AUC), and precision was evaluated by confidence intervals (CIs) of AUC. Results: When applied to the 4 groups of tumor features, the LR model achieved AUCs (95% CI) of 0.57 (0.10), 0.73 (0.07), 0.90 (0.06), and 0.90 (0.06). The SVM model achieved AUCs (95% CI) of 0.56 (0.07), 0.60 (0.06), 0.94 (0.02), and 1.00 (no misclassifications). With the use of spatial-temporal PET features combined with conventional PET/CT measures and clinical parameters, the SVM model achieved very high accuracy (AUC 1.00) and precision (no misclassifications)—results that were significantly better than when conventional PET/CT measures or clinical parameters and demographics alone were used. For groups with many tumor features (groups 3 and 4), the SVM model achieved significantly higher accuracy than

  11. Public Pension Reform, Demographics, and Inequality

    OpenAIRE

    von Weizsäcker, Robert K

    1994-01-01

    Starting from a simple, descriptive model of individual income, an explicit link between the age composition of a population and the personal distribution of incomes is established. Demographic effects on income inequality are derived. Next, a pay-as-you-go financed state pension system is introduced. The resulting government budget constraint entails interrelations between fiscal and demographic variables, causing an additional, indirect demographic impact on the distribution. This is shown ...

  12. A combined model to assess technical and economic consequences of changing conditions and management options for wastewater utilities.

    Science.gov (United States)

    Giessler, Mathias; Tränckner, Jens

    2018-02-01

    The paper presents a simplified model that quantifies economic and technical consequences of changing conditions in wastewater systems on utility level. It has been developed based on data from stakeholders and ministries, collected by a survey that determined resulting effects and adapted measures. The model comprises all substantial cost relevant assets and activities of a typical German wastewater utility. It consists of three modules: i) Sewer for describing the state development of sewer systems, ii) WWTP for process parameter consideration of waste water treatment plants (WWTP) and iii) Cost Accounting for calculation of expenses in the cost categories and resulting charges. Validity and accuracy of this model was verified by using historical data from an exemplary wastewater utility. Calculated process as well as economic parameters shows a high accuracy compared to measured parameters and given expenses. Thus, the model is proposed to support strategic, process oriented decision making on utility level. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Follower Jealousy at Work: A Test of Vecchio's Model of Antecedents and Consequences of Jealousy.

    Science.gov (United States)

    Thompson, Geir; Buch, Robert; Glasø, Lars

    2018-01-02

    The present study tests the validity of Robert P. Vecchio's seminal work on antecedents and consequences of jealousy. Specifically, we examine whether antecedents such as in-group status, supervisory considerateness, and supervisory differentiation of subordinates are associated with jealousy. In addition, we examine whether jealousy is associated with the outcome variable of social loafing. Leaders (n = 73) and their followers (n = 303) working in business organizations in Norway contributed data. Multilevel analyses showed that a high-quality working relationship with one's supervisor was inversely related to reports of jealousy. In addition, supervisors who displayed high levels of considerateness, for example, by providing followers with positive emotional support, were better able to reduce subordinate jealousy. This is a novel observation since previous research failed to demonstrate such a relationship. Finally, jealousy was positively associated with social loafing, suggesting that jealous followers engaged in an active counterproductive resistance response. The present study contributes to the extant literature by identifying unexamined antecedents of jealousy and a dysfunctional behavioral response to jealousy in the form of social loafing in the workplace.

  14. Evaluating Outdoor Water Use Demand under Changing Climatic and Demographic Conditions: An Agent-based Modeling Approach

    Science.gov (United States)

    Kanta, L.; Berglund, E. Z.; Soh, M. H.

    2017-12-01

    Outdoor water-use for landscape and irrigation constitutes a significant end-use in total residential water demand. In periods of water shortages, utilities may reduce garden demands by implementing irrigation system audits, rebate programs, local ordinances, and voluntary or mandatory water-use restrictions. Because utilities do not typically record outdoor and indoor water-uses separately, the effects of policies for reducing garden demands cannot be readily calculated. The volume of water required to meet garden demands depends on the housing density, lawn size, type of vegetation, climatic conditions, efficiency of garden irrigation systems, and consumer water-use behaviors. Many existing outdoor demand estimation methods are deterministic and do not include consumer responses to conservation campaigns. In addition, mandatory restrictions may have a substantial impact on reducing outdoor demands, but the effectiveness of mandatory restrictions depends on the timing and the frequency of restrictions, in addition to the distribution of housing density and consumer types within a community. This research investigates a garden end-use model by coupling an agent-based modeling approach and a mechanistic-stochastic water demand model to create a methodology for estimating garden demand and evaluating demand reduction policies. The garden demand model is developed for two water utilities, using a diverse data sets, including residential customer billing records, outdoor conservation programs, frequency and type of mandatory water-use restrictions, lot size distribution, population growth, and climatic data. A set of garden irrigation parameter values, which are based on the efficiency of irrigation systems and irrigation habits of consumers, are determined for a set of conservation ordinances and restrictions. The model parameters are then validated using customer water usage data from the participating water utilities. A sensitivity analysis is conducted for garden

  15. Forecasting consequences of accidental release: how reliable are current assessment models

    International Nuclear Information System (INIS)

    Rohwer, P.S.; Hoffman, F.O.; Miller, C.W.

    1983-01-01

    This paper focuses on uncertainties in model output used to assess accidents. We begin by reviewing the historical development of assessment models and the associated interest in uncertainties as these evolutionary processes occurred in the United States. This is followed by a description of the sources of uncertainties in assessment calculations. Types of models appropriate for assessment of accidents are identified. A summary of results from our analysis of uncertainty is provided in results obtained with current methodology for assessing routine and accidental radionuclide releases to the environment. We conclude with discussion of preferred procedures and suggested future directions to improve the state-of-the-art of radiological assessments

  16. Demographic population model for American shad: will access to additional habitat upstream of dams increase population sizes?

    Science.gov (United States)

    Harris, Julianne E.; Hightower, Joseph E.

    2012-01-01

    American shad Alosa sapidissima are in decline in their native range, and modeling possible management scenarios could help guide their restoration. We developed a density-dependent, deterministic, stage-based matrix model to predict the population-level results of transporting American shad to suitable spawning habitat upstream of dams on the Roanoke River, North Carolina and Virginia. We used data on sonic-tagged adult American shad and oxytetracycline-marked American shad fry both above and below dams on the Roanoke River with information from other systems to estimate a starting population size and vital rates. We modeled the adult female population over 30 years under plausible scenarios of adult transport, effective fecundity (egg production), and survival of adults (i.e., to return to spawn the next year) and juveniles (from spawned egg to age 1). We also evaluated the potential effects of increased survival for adults and juveniles. The adult female population size in the Roanoke River was estimated to be 5,224. With no transport, the model predicted a slow population increase over the next 30 years. Predicted population increases were highest when survival was improved during the first year of life. Transport was predicted to benefit the population only if high rates of effective fecundity and juvenile survival could be achieved. Currently, transported adults and young are less likely to successfully out-migrate than individuals below the dams, and the estimated adult population size is much smaller than either of two assumed values of carrying capacity for the lower river; therefore, transport is not predicted to help restore the stock under present conditions. Research on survival rates, density-dependent processes, and the impacts of structures to increase out-migration success would improve evaluation of the potential benefits of access to additional spawning habitat for American shad.

  17. Clinical, laboratory, and demographic determinants of hospitalization due to dengue in 7613 patients: A retrospective study based on hierarchical models.

    Science.gov (United States)

    da Silva, Natal Santos; Undurraga, Eduardo A; da Silva Ferreira, Elis Regina; Estofolete, Cássia Fernanda; Nogueira, Maurício Lacerda

    2018-01-01

    In Brazil, the incidence of hospitalization due to dengue, as an indicator of severity, has drastically increased since 1998. The objective of our study was to identify risk factors associated with subsequent hospitalization related to dengue. We analyzed 7613 dengue confirmed via serology (ELISA), non-structural protein 1, or polymerase chain reaction amplification. We used a hierarchical framework to generate a multivariate logistic regression based on a variety of risk variables. This was followed by multiple statistical analyses to assess hierarchical model accuracy, variance, goodness of fit, and whether or not this model reliably represented the population. The final model, which included age, sex, ethnicity, previous dengue infection, hemorrhagic manifestations, plasma leakage, and organ failure, showed that all measured parameters, with the exception of previous dengue, were statistically significant. The presence of organ failure was associated with the highest risk of subsequent dengue hospitalization (OR=5·75; CI=3·53-9·37). Therefore, plasma leakage and organ failure were the main indicators of hospitalization due to dengue, although other variables of minor importance should also be considered to refer dengue patients to hospital treatment, which may lead to a reduction in avoidable deaths as well as costs related to dengue. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Evaluation of dose calculation models for inhabited areas applicable in nuclear accident consequence assessment codes

    International Nuclear Information System (INIS)

    Katalin Eged; Zoltan Kis; Natalia Semioschkina; Gabriele Voigt

    2004-01-01

    One of the objectives of the EC project EVANET-TERRA is to provide suitable inputs to the RODOS system. This study gives an overview on urban dose calculation models with special emphasis on the RECLAIM-EDEM2M and TEMAS-urban codes. The TEMAS-urban code is more complex compared to the RECLAIM-EDEM2M code although both models use similar and some times even same model parameters. The database and the way of its data collection as used in RECLAIM-EDEM2M is recommended as a preferred option because it contains many data from local and regional measurements. However in a decision situation the outputs of the TEMASurban model may better help stake holders by providing a ranking of the surfaces to be decontaminated. (author)

  19. Consequences of observed Bd-anti Bd mixing in standard and nonstandard models

    International Nuclear Information System (INIS)

    Datta, A.; Paschos, E.A.; Tuerke, U.

    1987-01-01

    Implications of the B d -anti B d mixing report by the ARGUS group are investigated. We show that in order for the standard model to accomodate the result, the B → anti B hadronic matrix element must satisfy lower bounds as a function of top quark mass. In this case B S -anti B S mixing is necessarily large (r S > or approx. 0.74) irrespective of m t . This conclusion remains valid in several popular extensions of the standard model with three generations. In contrast to these models, four generation models can accomodate simultaneously the observed B d -anti B d mixing and a relatively small B S -anti B S mixing. (orig.)

  20. The Total Cross Section at the LHC: Models and Experimental Consequences

    CERN Document Server

    Cudell, J R

    2010-01-01

    I review the predictions of the total cross section for many models, and point out that some of them lead to the conclusion that the standard experimental analysis may lead to systematic errors much larger than expected.

  1. Increasing biological diversity in a dynamic vegetation model and consequences for simulated response to climate change

    Science.gov (United States)

    Keribin, R. M.; Friend, A. D.; Purves, D.; Smith, M. J.

    2013-12-01

    Vegetation, from tropical rainforests to the tundra, is the basis of the world food chain but is also a key component of the Earth system, with biophysical and biogeochemical impacts on the global climate, and Dynamic Global Vegetation Models (DGVMs) are an important integrative tool for understanding its responses to climate change. DGVMs up to now have treated only a small number of plant types representing broad divisions in vegetation worldwide (e.g. trees and grasses, broadleaf and needleleaf, deciduousness), but these categories ignore most of the variation that exists between plant species and between individuals within a species. Research in community ecology makes it clear however that these variations can affect large-scale ecosystem properties such as productivity and resilience to environmental changes. The current challenge is for DGVMs to account for fine-grained variations between plants and a few such models are being developed using newly-available plant trait databases such as the TRY database and insights from community ecology such as habitat filtering. Hybrid is an individual-based DGVM, first published in 1993, that models plant physiology in a mechanistic way. We modified Hybrid 8, the latest version of the model which uses surface physics taken from the GISS ModelE GCM, to include a mechanistic gap-model component with individual-based variation in tree wood density. This key plant trait is known to be strongly correlated with a trade-off between growth and mortality in the majority of forests worldwide, which allows for otherwise-similar individuals to have different life-history strategies. We investigate how the inclusion of continuous variation in wood density into the model affects the ecosystem's transient dynamics under climate change.

  2. A Propagative Model of Simultaneous Impact: Existence, Uniqueness, and Design Consequences

    OpenAIRE

    Seghete, Vlad; Murphey, Todd

    2017-01-01

    This paper presents existence and uniqueness results for a propagative model of simultaneous impacts that is guaranteed to conserve energy and momentum in the case of elastic impacts with extensions to perfectly plastic and inelastic impacts. A corresponding time-stepping algorithm that guarantees conservation of continuous energy and discrete momentum is developed, also with extensions to plastic and inelastic impacts. The model is illustrated in simulation using billiard balls and a two-dim...

  3. Health effects models for nuclear power plant accident consequence analysis: Low LET radiation

    International Nuclear Information System (INIS)

    Evans, J.S.

    1990-01-01

    This report describes dose-response models intended to be used in estimating the radiological health effects of nuclear power plant accidents. Models of early and continuing effects, cancers and thyroid nodules, and genetic effects are provided. Weibull dose-response functions are recommended for evaluating the risks of early and continuing health effects. Three potentially lethal early effects -- the hematopoietic, pulmonary, and gastrointestinal syndromes -- are considered. In addition, models are included for assessing the risks of several nonlethal early and continuing effects -- including prodromal vomiting and diarrhea, hypothyroidism and radiation thyroiditis, skin burns, reproductive effects, and pregnancy losses. Linear and linear-quadratic models are recommended for estimating cancer risks. Parameters are given for analyzing the risks of seven types of cancer in adults -- leukemia, bone, lung, breast, gastrointestinal, thyroid, and ''other.'' The category, ''other'' cancers, is intended to reflect the combined risks of multiple myeloma, lymphoma, and cancers of the bladder, kidney, brain, ovary, uterus and cervix. Models of childhood cancers due to in utero exposure are also developed. For most cancers, both incidence and mortality are addressed. The models of cancer risk are derived largely from information summarized in BEIR III -- with some adjustment to reflect more recent studies. 64 refs., 18 figs., 46 tabs

  4. Health effects models for nuclear power plant accident consequence analysis: Low LET radiation

    Energy Technology Data Exchange (ETDEWEB)

    Evans, J.S. (Harvard Univ., Boston, MA (USA). School of Public Health)

    1990-01-01

    This report describes dose-response models intended to be used in estimating the radiological health effects of nuclear power plant accidents. Models of early and continuing effects, cancers and thyroid nodules, and genetic effects are provided. Weibull dose-response functions are recommended for evaluating the risks of early and continuing health effects. Three potentially lethal early effects -- the hematopoietic, pulmonary, and gastrointestinal syndromes -- are considered. In addition, models are included for assessing the risks of several nonlethal early and continuing effects -- including prodromal vomiting and diarrhea, hypothyroidism and radiation thyroiditis, skin burns, reproductive effects, and pregnancy losses. Linear and linear-quadratic models are recommended for estimating cancer risks. Parameters are given for analyzing the risks of seven types of cancer in adults -- leukemia, bone, lung, breast, gastrointestinal, thyroid, and other.'' The category, other'' cancers, is intended to reflect the combined risks of multiple myeloma, lymphoma, and cancers of the bladder, kidney, brain, ovary, uterus and cervix. Models of childhood cancers due to in utero exposure are also developed. For most cancers, both incidence and mortality are addressed. The models of cancer risk are derived largely from information summarized in BEIR III -- with some adjustment to reflect more recent studies. 64 refs., 18 figs., 46 tabs.

  5. Complexity and demographic explanations of cumulative culture

    NARCIS (Netherlands)

    Querbes, A.; Vaesen, K.; Houkes, W.N.

    2014-01-01

    Formal models have linked prehistoric and historical instances of technological change (e.g., the Upper Paleolithic transition, cultural loss in Holocene Tasmania, scientific progress since the late nineteenth century) to demographic change. According to these models, cumulation of technological

  6. Hmong demographic changes in Laos: causes and ecological consequences.

    Science.gov (United States)

    Ireson, W R

    1995-10-01

    This study of the Hmong in Laos is based on ethnographic research conducted during a three week stay in the Nong Het district of Xieng Khouang province. Information was collected on the household agricultural economy, village and household movement, family composition and change, cropping and animal husbandry, and environmental resources. The study area east of the Mekong River and near the Vietnamese border is an infrequently studied area. Findings differ from the ethnographic literature that portrays the Hmong as migrating frequently as swidden fields are exhausted, as living in large extended families, and as polygynous. The Hmong are the second largest minority in Laos (231,000), but are only 0.1% of Thailand's total population (90,000). There are 558,000 Hmong in Vietnam, but 5 million in China. Most rural Hmong in Laos produce opium as a necessary crop for sustaining their household farming economy. Although areas near the study area were involved in major military action during 1960-73, the study area received minimal disruption. Four studies of the Hmong in Laos and Thailand indicated that the Hmong stayed at one residence about 7 years, that residence varied from 6-16 years, and that settlements were short-lived. Household size ranged from 4 to 47 households. The Hmong in this study were more sedentary. In 1990, the villages averaged about 45 households. The population ranged in age from 19 years to 87 years. The Hmong had a high birth rate and a high mortality rate due to poor diet and lack of adequate medical care. 45% of the Nong Het population were aged under 14 years, which suggests a baby boom after the war. The dependency ratio was very high. Polygyny was uncommon. Of the 154 households, the average size was small at 7.40 persons. 71% were nuclear families. Patrilocal residence after marriage was still practiced, but the time spent in the father's home was reduced. The findings suggest that the Hmong are likely to become sedentary due to limits on expansion of swidden farming and government controls. It is unlikely that the Hmong will become landless and depend upon wage labor.

  7. Demographic and medical consequences of the postponement of parenthood

    DEFF Research Database (Denmark)

    Schmidt, Lone; Sobotka, Tomas; Bentzen, Janne Gasseholm

    2012-01-01

    pronounced effects >35 years, whereas the increasing risk of preterm births and stillbirths starts at around 35 years with a more pronounced effect >40 years. Advanced male age has an important but less pronounced effect on infertility and adverse outcomes. MAR treatment cannot overcome the age...... databases were searched for publications on relevant subjects such as delayed parenthood, female and male age, fertility, infertility, time to pregnancy (TTP), fetal death, outcome of medically assisted reproduction (MAR) and mental well-being. RESULTS Postponement of parenthood is linked to a higher rate...... of involuntary childlessness and smaller families than desired due to increased infertility and fetal death with higher female and male age. For women, the increased risk of prolonged TTP, infertility, spontaneous abortions, ectopic pregnancies and trisomy 21 starts at around 30 years of age with a more...

  8. Laboratory Demographics Lookup Tool

    Data.gov (United States)

    U.S. Department of Health & Human Services — This website provides demographic information about laboratories, including CLIA number, facility name and address, where the laboratory testing is performed, the...

  9. Endothelial Dysfunction in Experimental Models of Arterial Hypertension: Cause or Consequence?

    Directory of Open Access Journals (Sweden)

    Iveta Bernatova

    2014-01-01

    Full Text Available Hypertension is a risk factor for other cardiovascular diseases and endothelial dysfunction was found in humans as well as in various commonly employed animal experimental models of arterial hypertension. Data from the literature indicate that, in general, endothelial dysfunction would not be the cause of experimental hypertension and may rather be secondary, that is, resulting from high blood pressure (BP. The initial mechanism of endothelial dysfunction itself may be associated with a lack of endothelium-derived relaxing factors (mainly nitric oxide and/or accentuation of various endothelium-derived constricting factors. The involvement and role of endothelium-derived factors in the development of endothelial dysfunction in individual experimental models of hypertension may vary, depending on the triggering stimulus, strain, age, and vascular bed investigated. This brief review was focused on the participation of endothelial dysfunction, individual endothelium-derived factors, and their mechanisms of action in the development of high BP in the most frequently used rodent experimental models of arterial hypertension, including nitric oxide deficient models, spontaneous (prehypertension, stress-induced hypertension, and selected pharmacological and diet-induced models.

  10. MODELLING OF THE POSSIBLE INTEGRATION CONSEQUENCES OF THE ECONOMY OF UKRAINE INTO THE ECONOMIES OF THE EUROPEAN UNION OR RUSSIA

    Directory of Open Access Journals (Sweden)

    Lesya Buyak

    2016-11-01

    Full Text Available The purpose of the paper is to mathematically reproduce the process of economic partnership between the two countries and its qualitative analysis, which include the following goals: to identify feasible outcomes, to formulate requirements for the selection of control parameters and coefficients, to give economic reasoning of the results of modelling and to provide alternative scenario of economic cooperation. Methodology. A method of mathematical modelling has been applied to investigate the possible socio-economic impact of integration of Ukraine into the EU economy. We are describing the basic mathematical model of the economy of Ukraine and two mathematical models of the possible convergence with the economies of the European Union or Russia. The results of modelling are reflected by the capacity of relevant dynamic systems and the quantitative distribution of savings. Results. On the basis of economic analysis of mathematical dependence, the conclusions on the possible economic consequences of integration of Ukraine into the economy of the European Union or Russia have been established. Practical implications. It has been found that a step towards the European Union (EU requires the alteration of principles of economic management, timely government control. This should be done in the process of restructuring of social standards and commercial activity in terms of traditional forms of management of enterprises with low financial capacities. The process of convergence with the economy of Russia leads to conservation of the modern type of economy with many disadvantages of commercial management and government control as well as limitation of economic and political freedoms and growth of political instability in the country. Value/originality. The got results extend modern economic and mathematical tool for research of integration processes and acceptance of the proper economic decisions. Formalization of models of economy taking into account

  11. Modeling chiral criticality and its consequences for heavy-ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Almási, Gábor András, E-mail: g.almasi@gsi.de [Gesellschaft für Schwerionenforschung, GSI, D-64291 Darmstadt (Germany); Friman, Bengt, E-mail: b.friman@gsi.de [Gesellschaft für Schwerionenforschung, GSI, D-64291 Darmstadt (Germany); ExtreMe Matter Institute (EMMI), D-64291 Darmstadt (Germany); Redlich, Krzysztof, E-mail: krzysztof.redlich@ift.uni.wroc.pl [ExtreMe Matter Institute (EMMI), D-64291 Darmstadt (Germany); University of Wrocław - Faculty of Physics and Astronomy, PL-50-204 Wrocław (Poland); Department of Physics, Duke University, Durham, NC 27708 (United States)

    2016-12-15

    We explore the critical fluctuations near the chiral critical endpoint (CEP) in a chiral effective model and discuss possible signals of the CEP, recently explored experimentally in nuclear collision. Particular attention is paid to the dependence of such signals on the location of the phase boundary and the CEP relative to the chemical freeze-out conditions in nuclear collisions. We argue that in effective models, standard freeze-out fits to heavy-ion data should not be used directly. Instead, the relevant quantities should be examined on lines in the phase diagram that are defined self-consistently, within the framework of the model. We discuss possible choices for such an approach.

  12. Modelling shelf-ocean exchange and its biogeochemical consequences in coastal upwelling systems

    DEFF Research Database (Denmark)

    Muchamad, Al Azhar

    margin bathymetry, and 3) what processes determine the observed variability of total organic carbon (TOC) content in shelf sediments underlying the upwelling system, with implications for the formation of petroleum source rocks. Here, a numerical ocean modeling approach is used in this thesis to explore...... processes and the development of anoxia/euxinia under the present day or past geological conditions. Thirdly and last, processes controlling distribution of total organic carbon (TOC) content in sediments across the continental margin is evaluated by application of the model to the Benguela upwelling system....... In the model, biological primary production and shelf bottom-water anoxia result in enhanced sedimentary TOC concentrations on the mid shelf and upper slope. The simulated TOCs implicate that bottom lateral transport only has a significant effect on increasing the deposition of the organic carbon on the mid...

  13. Modeling chiral criticality and its consequences for heavy-ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Almasi, Gabor [Gesellschaft fuer Schwerionenforschung, GSI, Darmstadt (Germany); Friman, Bengt [Gesellschaft fuer Schwerionenforschung, GSI, Darmstadt (Germany); ExtreMe Matter Institute (EMMI), Darmstadt (Germany); Redlich, Krzysztof [ExtreMe Matter Institute (EMMI), Darmstadt (Germany); University of Wroclaw, Faculty of Physics and Astronomy, Wroclaw (Poland); Department of Physics, Duke University, Durham, NC (United States)

    2016-07-01

    We explore the critical fluctuations near the chiral critical endpoint (CEP), which belongs to the Z(2) universality class, in a chiral effective model and discuss possible signals of the CEP, recently explored in nuclear collision experiments. Particular attention is attributed to the dependence of such signals on the location of the phase boundary and the CEP relative to the hypothetical freeze-out conditions in nuclear collisions. We argue that in effective models freeze-out fits to heavy-ion results should not be used directly, and relevant quantities should be investigated on lines of the phase diagram, that are defined self-consistently in the framework of the model. We discuss possible choices for such an approach. Additionally we discuss the effect of the repulsive vector interaction of quarks on the location of the CEP and on the structure of the baryon number cumulant ratios.

  14. Exploring geological and socio-demographic factors associated with under-five mortality in the Wenchuan earthquake using neural network model.

    Science.gov (United States)

    Hu, Yi; Wang, Jinfeng; Li, Xiaohong; Ren, Dan; Driskell, Luke; Zhu, Jun

    2012-01-01

    On 12 May 2008, a devastating earthquake occurred in Sichuan Province, China, taking tens of thousands of lives and destroying the homes of millions of people. Among the large number of dead or missing were children, particularly children aged less than five years old, a fact which drew significant media attention. To obtain relevant information specifically to aid further studies and future preventative measures, a neural network model was proposed to explore some geological and socio-demographic factors associated with earthquake-related child mortality. Sensitivity analysis showed that topographic slope (mean 35.76%), geomorphology (mean 24.18%), earthquake intensity (mean 13.68%), and average income (mean 11%) had great contributions to child mortality. These findings could provide some clues to researchers for further studies and to policy makers in deciding how and where preventive measures and corresponding policies should be implemented in the reconstruction of communities.

  15. Generic uncertainty model for DETRA for environmental consequence analyses. Application and sample outputs

    International Nuclear Information System (INIS)

    Suolanen, V.; Ilvonen, M.

    1998-10-01

    Computer model DETRA applies a dynamic compartment modelling approach. The compartment structure of each considered application can be tailored individually. This flexible modelling method makes it possible that the transfer of radionuclides can be considered in various cases: aquatic environment and related food chains, terrestrial environment, food chains in general and food stuffs, body burden analyses of humans, etc. In the former study on this subject, modernization of the user interface of DETRA code was carried out. This new interface works in Windows environment and the usability of the code has been improved. The objective of this study has been to further develop and diversify the user interface so that also probabilistic uncertainty analyses can be performed by DETRA. The most common probability distributions are available: uniform, truncated Gaussian and triangular. The corresponding logarithmic distributions are also available. All input data related to a considered case can be varied, although this option is seldomly needed. The calculated output values can be selected as monitored values at certain simulation time points defined by the user. The results of a sensitivity run are immediately available after simulation as graphical presentations. These outcomes are distributions generated for varied parameters, density functions of monitored parameters and complementary cumulative density functions (CCDF). An application considered in connection with this work was the estimation of contamination of milk caused by radioactive deposition of Cs (10 kBq(Cs-137)/m 2 ). The multi-sequence calculation model applied consisted of a pasture modelling part and a dormant season modelling part. These two sequences were linked periodically simulating the realistic practice of care taking of domestic animals in Finland. The most important parameters were varied in this exercise. The performed diversifying of the user interface of DETRA code seems to provide an easily

  16. Consequences of the partial restoration of chiral symmetry in an AdS/QCD model

    International Nuclear Information System (INIS)

    Kim, Youngman; Lee, Hyun Kyu

    2008-01-01

    Chiral symmetry is an essential concept in understanding QCD at low energy. We treat the chiral condensate, which measures the spontaneous breaking of chiral symmetry, as a free parameter to investigate the effect of partially restored chiral symmetry on the physical quantities in the framework of an AdS/QCD model. We observe an interesting scaling behavior among the nucleon mass, pion decay constant, and chiral condensate. We propose a phenomenological way to introduce the temperature dependence of a physical quantity in the AdS/QCD model with the thermal AdS metric.

  17. Evaluating environmental and economic consequences of alternative pest management strategies: results of modeling workshops

    Science.gov (United States)

    Johnson, Richard L.; Andrews, Austin K.; Auble, Gregor T.L.; Ellison, Richard A.; Hamilton, David B.; Roelle, James E.; McNamee, Peter J.

    1983-01-01

    The U.S. Environmental Protection Agency (EPA) needs a comprehensive method to evaluate the human health and environmental effects of alternative agricultural pest management strategies. This project explored the utility of Adaptive Environmental Assessment (AEA) techniques for meeting this need. The project objectives were to produce models for environmental impact analysis, improve communications, identify research needs and data requirements, and demonstrate a process for resolving conflicts. The project was structured around the construction (in an initial 2 1/2-day workshop) and examination (in a second 2 1/2-day workshop) of a simulation model of a corn agroecosystem.

  18. Experimental consequences of SU(3) symmetry in an sdg boson model

    International Nuclear Information System (INIS)

    Akiyama, Y.; Brentano, P. von; Gelberg, A.

    1987-01-01

    Energies of collective levels in 178 Hf and 234 U are compared wth predictions of the SU(3) limiz of the sdg interacting boson model. All known positive parity states of 178 Hf below 1.8 MeV (with the expection of a 0 + band) have been satisfactorily reproduced. Most of the bands in 234 U are also described by the model. However, a few predicted states have no experimental counterpart. The introduction of the g-basons strongly reduces the previously observed discrepancies between experimental B(E2)'s in 238 U and the sd-IBM calculation. (orig.)

  19. Experimental consequences of SU(3) symmetry in an sdg boson model

    Energy Technology Data Exchange (ETDEWEB)

    Akiyama, Y.; Brentano, P. von; Gelberg, A.

    1987-05-01

    Energies of collective levels in /sup 178/Hf and /sup 234/U are compared wth predictions of the SU(3) limiz of the sdg interacting boson model. All known positive parity states of /sup 178/Hf below 1.8 MeV (with the expection of a 0/sup +/ band) have been satisfactorily reproduced. Most of the bands in /sup 234/U are also described by the model. However, a few predicted states have no experimental counterpart. The introduction of the g-basons strongly reduces the previously observed discrepancies between experimental B(E2)'s in /sup 238/U and the sd-IBM calculation.

  20. Modeling activities in air traffic control systems: antecedents and consequences of a mid-air collision.

    Science.gov (United States)

    de Carvalho, Paulo Victor R; Ferreira, Bemildo

    2012-01-01

    In this article we present a model of some functions and activities of the Brazilian Air traffic Control System (ATS) in the period in which occurred a mid-air collision between flight GLO1907, a commercial aircraft Boeing 737-800, and flight N600XL, an executive jet EMBRAER E-145, to investigate key resilience characteristics of the ATM. Modeling in some detail activities during the collision and related them to overall behavior and antecedents that stress the organization uncover some drift into failure mechanisms that erode safety defenses provided by the Air Navigation Service Provider (ANSP), enabling a mid-air collision to be happen.

  1. Development of hydrogeological modelling approaches for assessment of consequences of hazardous accidents at nuclear power plants

    International Nuclear Information System (INIS)

    Rumynin, V.G.; Mironenko, V.A.; Konosavsky, P.K.; Pereverzeva, S.A.

    1994-07-01

    This paper introduces some modeling approaches for predicting the influence of hazardous accidents at nuclear reactors on groundwater quality. Possible pathways for radioactive releases from nuclear power plants were considered to conceptualize boundary conditions for solving the subsurface radionuclides transport problems. Some approaches to incorporate physical-and-chemical interactions into transport simulators have been developed. The hydrogeological forecasts were based on numerical and semi-analytical scale-dependent models. They have been applied to assess the possible impact of the nuclear power plants designed in Russia on groundwater reservoirs

  2. An Integrative Model for Understanding Team Organizational Citizenship Behavior: Its Antecedents and Consequences for Educational Teams

    Science.gov (United States)

    Somech, Anit; Khotaba, Soha

    2017-01-01

    Purpose: The purpose of this paper is to use a model to broaden the understanding of the organizational citizenship behavior (OCB) phenomenon in educational teams and examines team OCB's mediating role in the relation of the contextual variables of team justice climate (distributive justice, procedural justice, interpersonal justice) to team…

  3. Sensitivity Analysis of an Agent-Based Model of Culture's Consequences for Trade

    NARCIS (Netherlands)

    Burgers, S.L.G.E.; Jonker, C.M.; Hofstede, G.J.; Verwaart, D.

    2010-01-01

    This paper describes the analysis of an agent-based model’s sensitivity to changes in parameters that describe the agents’ cultural background, relational parameters, and parameters of the decision functions. As agent-based models may be very sensitive to small changes in parameter values, it is of

  4. Gender Consequences of a National Performance-Based Funding Model: New Pieces in an Old Puzzle

    Science.gov (United States)

    Nielsen, Mathias Wullum

    2017-01-01

    This article investigates the extent to which the Danish "Bibliometric Research Indicator" (BRI) reflects the performance of men and women differently. The model is based on a differentiated counting of peer-reviewed publications, awarding three and eight points for contributions to "well-regarded" and highly selective journals…

  5. Fuels planning: science synthesis and integration; environmental consequences fact sheet 15: The Wildlife Habitat Response Model

    Science.gov (United States)

    David Pilliod

    2005-01-01

    The Wildlife Habitat Response Model (WHRM) is a Web-based computer tool for evaluating the potential effects of fuel-reduction projects on terrestrial wildlife habitats. It uses species-habitat associations in ponderosa pine (Pinus ponderosa), dry-type Douglas-fir (Pseudotsuga menziesii), lodgepole pine (Pinus...

  6. Modelling Pre-eruptive Progressive Damage in Basaltic Volcanoes: Consequences for the Pre-eruptive Process

    Science.gov (United States)

    Got, J. L.; Amitrano, D.; Carrier, A.; Marsan, D.; Jouanne, F.; Vogfjord, K. S.

    2017-12-01

    At Grimsvötn volcano, high-quality earthquake and continuous GPS data were recorded by the Icelandic Meteorological Office during its 2004-2011 inter-eruptive period and exhibited remarkable patterns : acceleration of the cumulated earthquake number, and a 2-year exponential decrease in displacement rate followed by a 4-year constant inflation rate. We proposed a model with one magma reservoir in a non-linear elastic damaging edifice, with incompressible magma and a constant pressure at the base of the magma conduit. We first modelled seismicity rate and damage as a function of time, and show that Kachanov's elastic brittle damage law may be used to express the decrease of the effective shear modulus with time. We then derived simple analytical expressions for the magma reservoir overpressure and the surface displacement as a function of time. We got a very good fit of the seismicity and surface displacement data by adjusting only three phenomenological parameters and computed magma reservoir overpressure, magma flow and strain power as a function of time. Overpressure decrease is controlled by damage and shear modulus decrease. Displacement increases, although overpressure is decreasing, because shear modulus decreases more than overpressure. Normalized strain power reaches a maximum 0.25 value. This maximum is a physical limit, after which the elasticity laws are no longer valid, earthquakes cluster, cumulative number of earthquakes departs from the model. State variable extrema provide four reference times that may be used to assess the mechanical state and dynamics of the volcanic edifice. We also performed the spatial modelling of the progressive damage and strain localization around a pressurized magma reservoir. We used Kachanov's damage law and finite element modelling of an initially elastic volcanic edifice pressurized by a spherical magma reservoir, with a constant pressure in the reservoir and various external boundary conditions. At each node of the

  7. Testing a model of antecedents and consequences of defensive pessimism and self-handicapping in school physical education.

    Science.gov (United States)

    Ntoumanis, Nikos; Taylor, Ian M; Standage, Martyn

    2010-12-01

    There has been very limited research on the use of self-worth protection strategies in the achievement context of school physical education (PE). Thus the aim of the present study was to examine some antecedents and consequences of defensive pessimism and self-handicapping. The sample comprised 534 British pupils (275 females, 259 males) recruited from two schools who responded to established questionnaires. Results of structural equation modelling analysis indicated that self-handicapping and defensive pessimism were positively predicted by fear of failure and negatively predicted by competence valuation. In addition, defensive pessimism was negatively predicted by physical self-concept. In turn, defensive pessimism negatively predicted enjoyment in PE and intentions to participate in future optional PE programmes. Self-handicapping did not predict enjoyment or intentions. Results from multi-sample structural equation modelling showed the specified model to be largely invariant across males and females. The findings indicate that although both strategies aim to protect one's self-worth, some of their antecedents and consequences in PE may differ.

  8. Model development of SAS4A and investigation on the initiating phase consequences in LMFRs related with material motion

    International Nuclear Information System (INIS)

    Niwa, H.

    1994-01-01

    This paper focuses on an analytical aspect of the initiating phase scenario and consequences of postulated core disruptive accident in liquid-metal-cooled fast breeder reactors. An analytical code, SAS4A, has been developed at Argonne National Laboratory, and introduced to PNC. Improvement and validation effort have been performed for the mixed-oxide version of SAS4A at PNC. This paper describes firstly recent development of SAS4A's material motion related models briefly. A fission gas mass transfer model and solid fuel chunk jamming model are developed and introduced to SAS4A, and validated using CABRI-2 E13 experimental data. Secondly, an investigation of the mechanism of energetics in the initiating phase of an unprotected loss-of-flow accident has identified major control parameters which are intimately related to core design parameters and material motion phenomena. (author)

  9. A stochastic model for simulation of the economic consequences of bovine virus diarrhoea virus infection in a dairy herd

    DEFF Research Database (Denmark)

    Sørensen, J.T.; Enevoldsen, Carsten; Houe, H.

    1995-01-01

    A dynamic, stochastic model simulating the technical and economic consequences of bovine virus diarrhoea virus (BVDV) infections for a dairy cattle herd for use on a personal computer was developed. The production and state changes of the herd were simulated by state changes of the individual cows...... and heifers. All discrete events at the cow level were triggered stochastically. Each cow and heifer was characterized by state variables such as stage of lactation, parity, oestrous status, decision for culling, milk production potential, and immune status for BVDV. The model was controlled by 170 decision...... variables describing biologic and management variables including 21 decision variables describing the effect of BVDV infection on the production of the individual animal. Two markedly different scenarios were simulated to demonstrate the behaviour of the developed model and the potentials of the applied...

  10. Do we need demographic data to forecast plant population dynamics?

    Science.gov (United States)

    Tredennick, Andrew T.; Hooten, Mevin B.; Adler, Peter B.

    2017-01-01

    Rapid environmental change has generated growing interest in forecasts of future population trajectories. Traditional population models built with detailed demographic observations from one study site can address the impacts of environmental change at particular locations, but are difficult to scale up to the landscape and regional scales relevant to management decisions. An alternative is to build models using population-level data that are much easier to collect over broad spatial scales than individual-level data. However, it is unknown whether models built using population-level data adequately capture the effects of density-dependence and environmental forcing that are necessary to generate skillful forecasts.Here, we test the consequences of aggregating individual responses when forecasting the population states (percent cover) and trajectories of four perennial grass species in a semi-arid grassland in Montana, USA. We parameterized two population models for each species, one based on individual-level data (survival, growth and recruitment) and one on population-level data (percent cover), and compared their forecasting accuracy and forecast horizons with and without the inclusion of climate covariates. For both models, we used Bayesian ridge regression to weight the influence of climate covariates for optimal prediction.In the absence of climate effects, we found no significant difference between the forecast accuracy of models based on individual-level data and models based on population-level data. Climate effects were weak, but increased forecast accuracy for two species. Increases in accuracy with climate covariates were similar between model types.In our case study, percent cover models generated forecasts as accurate as those from a demographic model. For the goal of forecasting, models based on aggregated individual-level data may offer a practical alternative to data-intensive demographic models. Long time series of percent cover data already exist

  11. Prediction model for prevalence and incidence of advanced age-related macular degeneration based on genetic, demographic, and environmental variables.

    Science.gov (United States)

    Seddon, Johanna M; Reynolds, Robyn; Maller, Julian; Fagerness, Jesen A; Daly, Mark J; Rosner, Bernard

    2009-05-01

    The joint effects of genetic, ocular, and environmental variables were evaluated and predictive models for prevalence and incidence of AMD were assessed. Participants in the multicenter Age-Related Eye Disease Study (AREDS) were included in a prospective evaluation of 1446 individuals, of which 279 progressed to advanced AMD (geographic atrophy or neovascular disease) and 1167 did not progress during 6.3 years of follow-up. For prevalent AMD, 509 advanced cases were compared with 222 controls. Covariates for the incidence analysis included age, sex, education, smoking, body mass index (BMI), baseline AMD grade, and the AREDS vitamin-mineral treatment assignment. DNA specimens were evaluated for six variants in five genes related to AMD. Unconditional logistic regression analyses were performed for prevalent and incident advanced AMD. An algorithm was developed and receiver operating characteristic curves and C statistics were calculated to assess the predictive ability of risk scores to discriminate progressors from nonprogressors. All genetic polymorphisms were independently related to prevalence of advanced AMD, controlling for genetic factors, smoking, BMI, and AREDS treatment. Multivariate odds ratios (ORs) were 3.5 (95% confidence interval [CI], 1.7-7.1) for CFH Y402H; 3.7 (95% CI, 1.6-8.4) for CFH rs1410996; 25.4 (95% CI, 8.6-75.1) for LOC387715 A69S (ARMS2); 0.3 (95% CI, 0.1-0.7) for C2 E318D; 0.3 (95% CI, 0.1-0.5) for CFB; and 3.6 (95% CI, 1.4-9.4) for C3 R102G, comparing the homozygous risk/protective genotypes to the referent genotypes. For incident AMD, all these variants except CFB were significantly related to progression to advanced AMD, after controlling for baseline AMD grade and other factors, with ORs from 1.8 to 4.0 for presence of two risk alleles and 0.4 for the protective allele. An interaction was seen between CFH402H and treatment, after controlling for all genotypes. Smoking was independently related to AMD, with a multiplicative joint

  12. Cancer Stem Cells of Differentiated B-Cell Malignancies: Models and Consequences

    International Nuclear Information System (INIS)

    Gross, Emilie; Quillet-Mary, Anne; Ysebaert, Loic; Laurent, Guy; Fournie, Jean-Jacques

    2011-01-01

    The concept of cancer stem cells has revolutionized our current vision of cancer development and was validated in solid tumors and cancers of the primitive hematopoietic compartment. Proof of the principle is still lacking, however, in malignancies of differentiated B-cells. We review here the current literature, which nevertheless suggests hierarchical organizations of the tumor clone for mostly incurable B-cell cancers such as multiple myeloma, lymphomas and B-chronic lymphocytic leukemia. We propose two models accounting for cancer stem cells in these contexts: a “top-to-bottom” clonal hierarchy from memory B-cells and a “bottom-to-top” model of clonal reprogramming. Selection pressure on the growing tumor can drive such reprogramming and increase its genetic diversity

  13. Cancer Stem Cells of Differentiated B-Cell Malignancies: Models and Consequences

    Directory of Open Access Journals (Sweden)

    Jean-Jacques Fournie

    2011-03-01

    Full Text Available The concept of cancer stem cells has revolutionized our current vision of cancer development and was validated in solid tumors and cancers of the primitive hematopoietic compartment. Proof of the principle is still lacking, however, in malignancies of differentiated B-cells. We review here the current literature, which nevertheless suggests hierarchical organizations of the tumor clone for mostly incurable B-cell cancers such as multiple myeloma, lymphomas and B-chronic lymphocytic leukemia. We propose two models accounting for cancer stem cells in these contexts: a “top-to-bottom” clonal hierarchy from memory B-cells and a “bottom-to-top” model of clonal reprogramming. Selection pressure on the growing tumor can drive such reprogramming and increase its genetic diversity.

  14. Placebo Response is Driven by UCS Revaluation: Evidence, Neurophysiological Consequences and a Quantitative Model

    OpenAIRE

    Luca Puviani; Sidita Rama

    2016-01-01

    Despite growing scientific interest in the placebo effect and increasing understanding of neurobiological mechanisms, theoretical modeling of the placebo response remains poorly developed. The most extensively accepted theories are expectation and conditioning, involving both conscious and unconscious information processing. However, it is not completely understood how these mechanisms can shape the placebo response. We focus here on neural processes which can account for key properties of th...

  15. Modelling the potential consequences of future worldwide biomass energy demand for the french forests and timber

    International Nuclear Information System (INIS)

    Buongiorno, Joseph; Raunikar, Ronald; Zhu, Shushuai

    2011-01-01

    This article describes an investigation conducted, using a world model for the forestry and forest-based industries, on the effects of the current unpredictable changes in worldwide demand for biomass energy on this sector in France. Two contrasting scenarios are tested. The results are commented and the potential conflict between various would uses - workable timber, industrial timber and dendro-energy - is underscored. (authors)

  16. Predicting the Consequences of Workload Management Strategies with Human Performance Modeling

    Science.gov (United States)

    Mitchell, Diane Kuhl; Samma, Charneta

    2011-01-01

    Human performance modelers at the US Army Research Laboratory have developed an approach for establishing Soldier high workload that can be used for analyses of proposed system designs. Their technique includes three key components. To implement the approach in an experiment, the researcher would create two experimental conditions: a baseline and a design alternative. Next they would identify a scenario in which the test participants perform all their representative concurrent interactions with the system. This scenario should include any events that would trigger a different set of goals for the human operators. They would collect workload values during both the control and alternative design condition to see if the alternative increased workload and decreased performance. They have successfully implemented this approach for military vehicle. designs using the human performance modeling tool, IMPRINT. Although ARL researches use IMPRINT to implement their approach, it can be applied to any workload analysis. Researchers using other modeling and simulations tools or conducting experiments or field tests can use the same approach.

  17. Long-term consequences of a prolonged febrile seizure in a dual pathology model.

    Science.gov (United States)

    Gibbs, Steve; Chattopadhyaya, Bidisha; Desgent, Sébastien; Awad, Patricia N; Clerk-Lamalice, Olivier; Levesque, Maxime; Vianna, Rose-Mari; Rébillard, Rose-Marie; Delsemme, Andrée-Anne; Hébert, David; Tremblay, Luc; Lepage, Martin; Descarries, Laurent; Di Cristo, Graziella; Carmant, Lionel

    2011-08-01

    Clinical evidence suggests that febrile status epilepticus (SE) in children can lead to acute hippocampal injury and subsequent temporal lobe epilepsy. The contribution of febrile SE to the mechanisms underlying temporal lobe epilepsy are however poorly understood. A rat model of temporal lobe epilepsy following hyperthermic SE was previously established in our laboratory, wherein a focal cortical lesion induced at postnatal day 1 (P1), followed by a hyperthermic SE (more than 30 min) at P10, leads to hippocampal atrophy at P22 (dual pathology model) and spontaneous recurrent seizures (SRS) with mild visuospatial memory deficits in adult rats. The goal of this study was to identify the long term electrophysiological, anatomical and molecular changes in this model. Following hyperthermic SE, all cortically lesioned pups developed progressive SRS as adults, characterized by the onset of highly rhythmic activity in the hippocampus. A reduction of hippocampal volume on the side of the lesion preceded the SRS and was associated with a loss of hippocampal neurons, a marked decrease in pyramidal cell spine density, an increase in the hippocampal levels of NMDA receptor NR2A subunit, but no significant change in GABA receptors. These findings suggest that febrile SE in the abnormal brain leads to hippocampal injury that is followed by progressive network reorganization and molecular changes that contribute to the epileptogenesis as well as the observed memory deficits. Copyright © 2011 Elsevier Inc. All rights reserved.

  18. Animal models of extinction-induced depression: loss of reward and its consequences.

    Science.gov (United States)

    Huston, Joseph P; Silva, Maria A de Souza; Komorowski, Mara; Schulz, Daniela; Topic, Bianca

    2013-11-01

    The absence or loss of rewards or reinforcers holds a major role in the development of depression in humans. In spite of the prevalence of extinction-induced depression (EID) in humans, few attempts have been made to establish animal models thereof. Here we present the concept of extinction-related depression and summarize the results of two sets of studies in our attempt to create animal models of EID, one set based on extinction after positive reinforcement in the Skinner-box, the other on extinction after negative reinforcement - escape from water. We found various behaviors emitted during the extinction trials that responded to treatment with antidepressant drugs: Accordingly, the important behavioral marker for EID during extinction of escape from the water was immobility. During extinction after positive reinforcement the important indices for extinction-induced depression are the withdrawal from the former site of reward, biting behavior and rearing up on the hind legs. Avoidance behavior and biting may model aspects of human depressive behavior, which may include withdrawal or avoidance as well as aggressive-like behaviors. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Gap models and their individual-based relatives in the assessment of the consequences of global change

    Science.gov (United States)

    Shugart, Herman H.; Wang, Bin; Fischer, Rico; Ma, Jianyong; Fang, Jing; Yan, Xiaodong; Huth, Andreas; Armstrong, Amanda H.

    2018-03-01

    Individual-based models (IBMs) of complex systems emerged in the 1960s and early 1970s, across diverse disciplines from astronomy to zoology. Ecological IBMs arose with seemingly independent origins out of the tradition of understanding the ecosystems dynamics of ecosystems from a ‘bottom-up’ accounting of the interactions of the parts. Individual trees are principal among the parts of forests. Because these models are computationally demanding, they have prospered as the power of digital computers has increased exponentially over the decades following the 1970s. This review will focus on a class of forest IBMs called gap models. Gap models simulate the changes in forests by simulating the birth, growth and death of each individual tree on a small plot of land. The summation of these plots comprise a forest (or set of sample plots on a forested landscape or region). Other, more aggregated forest IBMs have been used in global applications including cohort-based models, ecosystem demography models, etc. Gap models have been used to provide the parameters for these bulk models. Currently, gap models have grown from local-scale to continental-scale and even global-scale applications to assess the potential consequences of climate change on natural forests. Modifications to the models have enabled simulation of disturbances including fire, insect outbreak and harvest. Our objective in this review is to provide the reader with an overview of the history, motivation and applications, including theoretical applications, of these models. In a time of concern over global changes, gap models are essential tools to understand forest responses to climate change, modified disturbance regimes and other change agents. Development of forest surveys to provide the starting points for simulations and better estimates of the behavior of the diversity of tree species in response to the environment are continuing needs for improvement for these and other IBMs.

  20. Dynamic modelling of costs and health consequences of school closure during an influenza pandemic

    Directory of Open Access Journals (Sweden)

    Xue Yiting

    2012-11-01

    Full Text Available Abstract Background The purpose of this article is to evaluate the cost-effectiveness of school closure during a potential influenza pandemic and to examine the trade-off between costs and health benefits for school closure involving different target groups and different closure durations. Methods We developed two models: a dynamic disease model capturing the spread of influenza and an economic model capturing the costs and benefits of school closure. Decisions were based on quality-adjusted life years gained using incremental cost-effectiveness ratios. The disease model is an age-structured SEIR compartmental model based on the population of Oslo. We studied the costs and benefits of school closure by varying the age targets (kindergarten, primary school, secondary school and closure durations (1–10 weeks, given pandemics with basic reproductive number of 1.5, 2.0 or 2.5. Results The cost-effectiveness of school closure varies depending on the target group, duration and whether indirect costs are considered. Using a case fatality rate (CFR of 0.1-0.2% and with current cost-effectiveness threshold for Norway, closing secondary school is the only cost-effective strategy, when indirect costs are included. The most cost-effective strategies would be closing secondary schools for 8 weeks if R0=1.5, 6 weeks if R0=2.0, and 4 weeks if R0= 2.5. For severe pandemics with case fatality rates of 1-2%, similar to the Spanish flu, or when indirect costs are disregarded, the optimal strategy is closing kindergarten, primary and secondary school for extended periods of time. For a pandemic with 2009 H1N1 characteristics (mild severity and low transmissibility, closing schools would not be cost-effective, regardless of the age target of school children. Conclusions School closure has moderate impact on the epidemic’s scope, but the resulting disruption to society imposes a potentially great cost in terms of lost productivity from parents’ work absenteeism.

  1. Socio-demographic and economics factors associated with suicide mortality in Iran, 2001-2010: application of a decomposition model.

    Science.gov (United States)

    Haghparast-Bidgoli, Hassan; Rinaldi, Giulia; Shahnavazi, Hossein; Bouraghi, Hamid; Kiadaliri, Aliasghar A

    2018-06-14

    Suicide is a major global health problem, especially among youth. Suicide is known to be associated with a variety of social, economic, political and religious factors, vary across geographical and cultural regions. The current study aimed to investigate the effects of socioeconomic factors on suicide mortality rate across different regions in Iran. The data on distribution of population and socio-economic factors (such as unemployment rate, divorce rate, urbanization rate, average household expenditure etc.) at province level were obtained from the Statistical Centre of Iran and the National Organization for Civil Registration. The data on the annual number of deaths caused by suicide in each province was extracted from the published reports of the Iranian Forensic Medicine Organization. We used a decomposition model to distinguish between spatial and temporal variation in suicide mortality. The average rate of suicide mortality was 5.5 per 100,000 population over the study period. Across the provinces (spatial variation), suicide mortality rate was positively associated with household expenditure and the proportion of people aged 15-24 and older than 65 years and was negatively associated with the proportion of literate people. Within the provinces (temporal variation), higher divorce rate was associated with higher suicide mortality. By excluding the outlier provinces, the results showed that in addition to the proportion of people aged 15-24 and older than 65, divorce and unemployment rates were also significant predictors of spatial variation in suicide mortality while divorce rate was associated with higher suicide mortality within provinces. The findings indicate that both spatial and temporal variations in suicide mortality rates across the provinces and over time are determined by a number of socio-economic factors. The study provides information that can be of importance in developing preventive strategies.

  2. Risk assessment and consequence modeling of BLEVE explosion wave phenomenon of LPG spherical tank in a refinery

    Directory of Open Access Journals (Sweden)

    Mohammad Kamaei

    2016-06-01

    Full Text Available Introduction: Although human industrial activities are as a part of efforts to achieve greater prosperity, the risks related to these activities are also expanding. Hazard identification and risk assessment in the oil and gas industries are essential to reduce the frequency and severity of accidents and minimize damage to people and property before their occurrence. The aim of this study was to evaluate the liquefied and pressurized petroleum gas spherical tanks in a refinery and assessing the risks of Boiling Liquid Expanding Vapor Explosion (BLEVE phenomenon. Material and Method: In this study, the risks of BLEVE phenomenon were assessed, using the Bowtie method. The consequences of explosion wave phenomenon and the resulting wave quantity and its impacts on the neighboring machineries and equipment were analyzed. PHAST software version 6.54 has been used for modeling the BLEVE phenomenon. Result: In this evaluation, generally five causes and two consequences were identified for BLEVE phenomenon. In order to reduce its consequences, forty-three controlling measures were introduced to prevent the BLEVE phenomenon and the impacts of 31 control measures were identified. According to the conducted analysis, it was found that the spherical tank blast wave caused by LPG can lead to explosion of close located tanks which can create a chain of explosions. Conclusion: The results of modeling and risk assessment can be used to identify the BLEVE phenomenon causes and its effects on nearby people and equipment. Based on these results, preventive controlling measures can be implemented and also be determined by adopting proper design and layout, margin of safety for personnel, equipment and accessories.

  3. Modelling for radiological and radioecological consequences of an accidental radionuclide release at Sea

    International Nuclear Information System (INIS)

    Paschoa, A.S.

    1997-01-01

    Full text: Scenarios concerning accidental releases of radionuclides into water bodies can be found in the open literature, mostly in connection with nuclear power plants located either onshore or inland. However, meager attention has been given to nuclear reactors used as energy sources for propulsion at sea, which are also subject to accidents. Such potential accidents may involve the loss of part of the reactor core to the surrounding water body. In addition of the initial instantaneous releases, one can estimate delayed source terms based on the rate at which radionuclides are dissolved or leached from the solidified material, like part of the core or structural materials in contact with water. Most of such solidified material might be a mixture of uranium, zirconium, iron, calcium, silica, fission and activation products, and transuranium elements as oxides, forming a glassy type solid. Transport models were used to calculate radionuclide concentrations in water resulting from short and delayed source terms. Oceanographic data used in the calculations were taken either from the open literature or from unclassified reports of the Brazilian Navy, being, however, as generic as possible. Time-dependent concentration functions for radionuclides in aquatic food following an accidental release reflect the net result of intake and elimination processes. However, to avoid the complexities of multiple parameters involved in such processes, the model accounts only for trophic transfer of radionuclides, and yet avoids the necessity of analyzing the details of each transfer step used to determine fish, crustacea, molluscs and seaweed accumulation. Swimming and other aquatic sports are not included in the model used for dose calculations because of theirs relatively low importance in comparison with the pathways concerning ingestion of aquatic food

  4. The consequences of neural degeneration regarding optimal cochlear implant position in scala tympani: a model approach.

    Science.gov (United States)

    Briaire, Jeroen J; Frijns, Johan H M

    2006-04-01

    Cochlear implant research endeavors to optimize the spatial selectivity, threshold and dynamic range with the objective of improving the speech perception performance of the implant user. One of the ways to achieve some of these goals is by electrode design. New cochlear implant electrode designs strive to bring the electrode contacts into close proximity to the nerve fibers in the modiolus: this is done by placing the contacts on the medial side of the array and positioning the implant against the medial wall of scala tympani. The question remains whether this is the optimal position for a cochlea with intact neural fibers and, if so, whether it is also true for a cochlea with degenerated neural fibers. In this study a computational model of the implanted human cochlea is used to investigate the optimal position of the array with respect to threshold, dynamic range and spatial selectivity for a cochlea with intact nerve fibers and for degenerated nerve fibers. In addition, the model is used to evaluate the predictive value of eCAP measurements for obtaining peri-operative information on the neural status. The model predicts improved threshold, dynamic range and spatial selectivity for the peri-modiolar position at the basal end of the cochlea, with minimal influence of neural degeneration. At the apical end of the array (1.5 cochlear turns), the dynamic range and the spatial selectivity are limited due to the occurrence of cross-turn stimulation, with the exception of the condition without neural degeneration and with the electrode array along the lateral wall of scala tympani. The eCAP simulations indicate that a large P(0) peak occurs before the N(1)P(1) complex when the fibers are not degenerated. The absence of this peak might be used as an indicator for neural degeneration.

  5. Modeling Population-Level Consequences of Polychlorinated Biphenyl Exposure in East Greenland Polar Bears.

    Science.gov (United States)

    Pavlova, Viola; Grimm, Volker; Dietz, Rune; Sonne, Christian; Vorkamp, Katrin; Rigét, Frank F; Letcher, Robert J; Gustavson, Kim; Desforges, Jean-Pierre; Nabe-Nielsen, Jacob

    2016-01-01

    Polychlorinated biphenyls (PCBs) can cause endocrine disruption, cancer, immunosuppression, or reproductive failure in animals. We used an individual-based model to explore whether and how PCB-associated reproductive failure could affect the dynamics of a hypothetical polar bear (Ursus maritimus) population exposed to PCBs to the same degree as the East Greenland subpopulation. Dose-response data from experimental studies on a surrogate species, the mink (Mustela vision), were used in the absence of similar data for polar bears. Two alternative types of reproductive failure in relation to maternal sum-PCB concentrations were considered: increased abortion rate and increased cub mortality. We found that the quantitative impact of PCB-induced reproductive failure on population growth rate depended largely on the actual type of reproductive failure involved. Critical potencies of the dose-response relationship for decreasing the population growth rate were established for both modeled types of reproductive failure. Comparing the model predictions of the age-dependent trend of sum-PCBs concentrations in females with actual field measurements from East Greenland indicated that it was unlikely that PCB exposure caused a high incidence of abortions in the subpopulation. However, on the basis of this analysis, it could not be excluded that PCB exposure contributes to higher cub mortality. Our results highlight the necessity for further research on the possible influence of PCBs on polar bear reproduction regarding their physiological pathway. This includes determining the exact cause of reproductive failure, i.e., in utero exposure versus lactational exposure of offspring; the timing of offspring death; and establishing the most relevant reference metrics for the dose-response relationship.

  6. Consequences of intramolecular dityrosine formation on a DNA-protein complex: a molecular modeling study

    International Nuclear Information System (INIS)

    Gras, Julien; Sy, Denise; Eon, Severine; Charlier, Michel; Spotheim-Maurizot, Melanie

    2005-01-01

    Irradiation of the free lac repressor with γ-rays abolishes protein's ability to specifically bind operator DNA. A possible radiation-induced protein damage is a dityrosine (DTyr) formed by two spatially close radiation-induced tyrosyl radicals. We performed the molecular modeling of complexes between operator DNA and DTyr-bearing parts (headpieces) of the repressor. The presence of DTyr affects the structure and the interactions between partners. A detailed analysis allows to conclude this damage can partially account for the loss of repressor ability to bind DNA

  7. Consequences of the Chernobyl accident as the basis for development of ecological and dosimetric models

    International Nuclear Information System (INIS)

    Balonov, M.I.

    1993-01-01

    The paper presents the materials of six year dynamic investigation of Cs and Sr radionuclides content in food products and body of inhabitants of contaminated regions of Russia, and of individual external doses of gamma radiation measured within thermoluminescent method. The models of formation of the dose of external gamma radiation and intake of Cs-134, -137 in body of inhabitants of contaminated locality are formed. The transfer factor from soil to vegetation and to food ration of man for Cs-134, 137 decreases with the half-period of 1 to 1.5 years and depends on soil type and agrochemical characteristics. (orig.)

  8. Consequences of shoaling of the Central American Seaway determined from modeling Nd isotopes

    Science.gov (United States)

    Sepulchre, P.; Arsouze, T.; Donnadieu, Y.; Dutay, J.-C.; Jaramillo, C.; Le Bras, J.; Martin, E.; Montes, C.; Waite, A. J.

    2014-03-01

    The Central American Seaway played a pivotal role in shaping global climate throughout the late Cenozoic. Recent geological surveys have provided new constraints on timing of the seaway shoaling, while neodymium isotopic (ɛNd) data measured on fossil teeth, debris, and ferromanganese crusts have helped define the history of water masses in the region. Here we provide the first 3-D simulations of ɛNd responses to the shoaling seaway. Our model suggests that a narrow and shallow seaway is sufficient to affect interoceanic circulation, that inflow/outflow balance between the Caribbean and the Antilles responds nonlinearly to sill depth, and that a seaway narrower than 400 km is consistent with an active Atlantic meridional overturning circulation during the late Miocene. Simulated ɛNd values in the Caribbean confirm that inputs from radiogenic Pacific waters in the Caribbean decrease as the seaway shoals. Despite model limitations, a comparison between our results and ɛNd values recorded in the Caribbean helps constrain the depth of the Central American Seaway through time, and we infer that a depth between 50 and 200 m could have been reached 10 Ma ago.

  9. Application of different failure criteria in fuel pin modelling and consequences for overpower transients in LMFBRs

    International Nuclear Information System (INIS)

    Kuczera, B.; Royl, P.

    1975-01-01

    The CAPRI-2 code system for analysis of hypothetical core disruptive accidents in LMFBRs has recently been coupled with the transient deformation model BREDA-2. The new code system determines thermal and mechanical loads under transient conditions for both, fresh and irradiated fuel and cladding, taking into account fuel restructuring as well as effects from fission gas and fuel and clad swelling. The system has been used for analysis of mild uncontrolled overpower transients in the SNR-300 to predict failure, and to initialize and calculate subsequent fuel coolant interaction (FCI). Thirteen channels have been coupled by point kinetics for the whole core analysis. Three different failure mechanisms and their influence on accident sequence have been investigated: clad melt-through; clad burst caused by internal pressure build-up; clad straining due to differential thermal expansion between fuel and clad cylinders. The results of these analyses show that each failure mechanism will lead to rather different failure and accident sequences. There is still a lack of experimental data from which failure thresholds can be derived. To get better predictions from the applied models an improved understanding of fission release and its relation to fuel porosity also some better experimental data on fluence and temperature dependent rupture strains of the cladding material should be available

  10. Analysis and modeling of a hail event consequences on a building portfolio

    Science.gov (United States)

    Nicolet, Pierrick; Voumard, Jérémie; Choffet, Marc; Demierre, Jonathan; Imhof, Markus; Jaboyedoff, Michel

    2014-05-01

    North-West Switzerland has been affected by a severe Hail Storm in July 2011, which was especially intense in the Canton of Aargau. The damage cost of this event is around EUR 105 Million only for the Canton of Aargau, which corresponds to half of the mean annual consolidated damage cost of the last 20 years for the 19 Cantons (over 26) with a public insurance. The aim of this project is to benefit from the collected insurance data to better understand and estimate the risk of such event. In a first step, a simple hail event simulator, which has been developed for a previous hail episode, is modified. The geometric properties of the storm is derived from the maximum intensity radar image by means of a set of 2D Gaussians instead of using 1D Gaussians on profiles, as it was the case in the previous version. The tool is then tested on this new event in order to establish its ability to give a fast damage estimation based on the radar image and buildings value and location. The geometrical properties are used in a further step to generate random outcomes with similar characteristics, which are combined with a vulnerability curve and an event frequency to estimate the risk. The vulnerability curve comes from a 2009 event and is improved with data from this event, whereas the frequency for the Canton is estimated from insurance records. In addition to this regional risk analysis, this contribution aims at studying the relation of the buildings orientation with the damage rate. Indeed, it is expected that the orientation of the roof influences the aging of the material by controlling the frequency and amplitude of thaw-freeze cycles, changing then the vulnerability over time. This part is established by calculating the hours of sunshine, which are used to derive the material temperatures. This information is then compared with insurance claims. A last part proposes a model to study the hail impact on a building, by modeling the different equipment on each facade of the

  11. The gauge properties of the dual model pomeron-reggeon vertex their derivation and their consequences

    CERN Document Server

    Brink, L; Scherk, J

    1973-01-01

    Study of the non-planar orientable single dual loop diagrams in 26 space-time dimensions has revealed an infinite positive-definite spectrum of 'pomeron' intermediate states which couple to reggeons via a bilinear pomeron-reggeon vertex operator. General algebraic techniques are developed to derive the behaviour of this vertex with respect to the Visasoro gauge operators. A reflection and transmission behaviour is found, reminiscent of the behaviour of a wave incident at the interface between two different media (in this case reggeonic and pomeronic). These gauge properties are such as to guarantee the desired 'good properties', namely completeness of the transverse reggeon states when coupled between physical reggeon states on one side, and on the other side, either physical pomeron states or else physical reggeon states created via an intermediate pomeron. This is yet another example of the amazing and gratifying self-consistency of the dual model with respect to duality, transversality and unitarity. (13 r...

  12. Mental models at work: cognitive causes and consequences of conflict in organizations.

    Science.gov (United States)

    Halevy, Nir; Cohen, Taya R; Chou, Eileen Y; Katz, James J; Panter, A T

    2014-01-01

    This research investigated the reciprocal relationship between mental models of conflict and various forms of dysfunctional social relations in organizations, including experiences of task and relationship conflicts, interpersonal hostility, workplace ostracism, and abusive supervision. We conceptualize individual differences in conflict construals as reflecting variation in people's belief structures about conflict and explore how different elements in people's associative networks-in particular, their beliefs about their best and worst strategy in conflict-relate to their personality, shape their experiences of workplace conflict, and influence others' behavioral intentions toward them. Five studies using a variety of methods (including cross-sectional surveys, a 12-week longitudinal diary study, and an experiment) show that the best strategy beliefs relate in theoretically meaningful ways to individuals' personality, shape social interactions and relationships significantly more than the worst strategy beliefs, and are updated over time as a result of individuals' ongoing experiences of conflict.

  13. The mechanical consequence of failure of ossified union in attempted posterior spinal fusion. A canine model.

    Science.gov (United States)

    Stonecipher, T K; Vanderby, R; Sciammarella, C A; Lei, S S; Fisk, J R

    1983-01-01

    The mechanical behavior of pseudarthrosis in posterior spinal fusion was investigated. A canine model was developed in which an incompletely ossified posterior fusion mass was consistently produced. The spines were excised, and the motion segments were mechanically tested using a specially developed loading apparatus. Tests were performed to evaluate stiffness of the segments to loading with compression, torsion, and anterioposterior and lateral bending shear stiffness. Changes in other modes of loading were less consistent. The motion characteristics of the pseudarthrosis could not be predicted from the extent of the osseous defect noted on roentgenograms. These findings correlate clinically with the progression of curvature seen with pseudarthrosis in scoliosis surgery and the unpredictable results of pseudarthrosis in posterior fusion performed in treatment of degenerative disc disease.

  14. Calculating the consequences of recovery, a European model for inhabited areas

    DEFF Research Database (Denmark)

    Charnock, T.W.; Jones, J.A.; Singer, L.N.

    2009-01-01

    The European Model for Inhabited Areas (ERMIN) was developed to allow a user to explore different recovery options following the contamination of an urban environment with radioactive material and to refine an appropriate strategy for the whole region affected. The input data include a description......, the contamination on urban surfaces, the activity concentration in air from resuspension, the doses to workers undertaking the recovery work, the quantity and activity of waste generated and the cost and work required to implement the countermeasure. ERMIN has been designed to be implemented as a tool that supports...... the approach of decision-makers and allows the area to be broken down into smaller regions where different conditions prevail and different countermeasure packages are enacted....

  15. Demographics and remote locations

    Energy Technology Data Exchange (ETDEWEB)

    Coppus, G. [Dynawise Inc., Calgary, AB (Canada)

    2005-07-01

    Within the next decade, the number of people leaving the workforce will exceed the number of new entrants. The demand for workers is expected to increase in Alberta due to oil sands industry growth. Sixty-four per cent of all responding federal, provincial, and municipal government organizations have reported shortages in their work environments, and almost 8 in 10 organizations predict they will continue to be understaffed in the next 3 to 5 years. Tightness in the general labour market will have an impact on employers in remote locations, and planning is essential to avoid the creation of a mercenary culture and a reliance on compensation. Challenges found in remote locations include high turnover rates among recent hires; critical gaps in service length; aggressive retirement; and the fact that the local population is often seen as unqualified for many industrial jobs. This Power Point presentation suggested that although decisions to join or quit a company are often based on considerations such as the organizational environment and amount of compensation, the relationship between employees and management is the most important attribute in many career decisions. Rigorous quantitative analysis of current demographics combined with forecasting analysis may help to forestall recruitment difficulties for many companies. Productivity analyses, and the effects of work overload on absenteeism, attrition and quality of workmanship must also be examined. Many companies are now focusing on retention and development strategies on mid-career staff to address depletion, as well as redesigning procedures to operate with less skilled staff. It was concluded that extra efforts are now being made to attract non-traditional employees, and non-traditional employment models are being considered by some companies. refs., tabs., figs.

  16. Modeling techniques for predicting long-term consequences of the effects of radiation on natural aquatic populations and ecosystems

    International Nuclear Information System (INIS)

    Van Winkle, W.

    1977-01-01

    Appropriate modeling techniques already exist for investigating some long-term consequences of the effects of radiation on natural aquatic populations and ecosystems, even if to date these techniques have not been used for this purpose. At the low levels of irradiation estimated to occur in natural aquatic systems, effects are difficult to detect at even the individual level much less the population or ecosystem level where the subtle effects of radiation are likely to be completely overshadowed by the effects of other environmental factors and stresses and the natural variability of the system. The claim that population and ecosystem models can be accurate and reliable predictive tools in assessing any stress has been oversold. Nonetheless, the use of these tools can be useful for learning more about the effects of radioactive releases on aquatic populations and ecosystems

  17. Health effects model for nuclear power plant accident consequence analysis. Part I. Introduction, integration, and summary. Part II. Scientific basis for health effects models

    Energy Technology Data Exchange (ETDEWEB)

    Evans, J.S.; Moeller, D.W.; Cooper, D.W.

    1985-07-01

    Analysis of the radiological health effects of nuclear power plant accidents requires models for predicting early health effects, cancers and benign thyroid nodules, and genetic effects. Since the publication of the Reactor Safety Study, additional information on radiological health effects has become available. This report summarizes the efforts of a program designed to provide revised health effects models for nuclear power plant accident consequence modeling. The new models for early effects address four causes of mortality and nine categories of morbidity. The models for early effects are based upon two parameter Weibull functions. They permit evaluation of the influence of dose protraction and address the issue of variation in radiosensitivity among the population. The piecewise-linear dose-response models used in the Reactor Safety Study to predict cancers and thyroid nodules have been replaced by linear and linear-quadratic models. The new models reflect the most recently reported results of the follow-up of the survivors of the bombings of Hiroshima and Nagasaki and permit analysis of both morbidity and mortality. The new models for genetic effects allow prediction of genetic risks in each of the first five generations after an accident and include information on the relative severity of various classes of genetic effects. The uncertainty in modeloling radiological health risks is addressed by providing central, upper, and lower estimates of risks. An approach is outlined for summarizing the health consequences of nuclear power plant accidents. 298 refs., 9 figs., 49 tabs.

  18. Health effects model for nuclear power plant accident consequence analysis. Part I. Introduction, integration, and summary. Part II. Scientific basis for health effects models

    International Nuclear Information System (INIS)

    Evans, J.S.; Moeller, D.W.; Cooper, D.W.

    1985-07-01

    Analysis of the radiological health effects of nuclear power plant accidents requires models for predicting early health effects, cancers and benign thyroid nodules, and genetic effects. Since the publication of the Reactor Safety Study, additional information on radiological health effects has become available. This report summarizes the efforts of a program designed to provide revised health effects models for nuclear power plant accident consequence modeling. The new models for early effects address four causes of mortality and nine categories of morbidity. The models for early effects are based upon two parameter Weibull functions. They permit evaluation of the influence of dose protraction and address the issue of variation in radiosensitivity among the population. The piecewise-linear dose-response models used in the Reactor Safety Study to predict cancers and thyroid nodules have been replaced by linear and linear-quadratic models. The new models reflect the most recently reported results of the follow-up of the survivors of the bombings of Hiroshima and Nagasaki and permit analysis of both morbidity and mortality. The new models for genetic effects allow prediction of genetic risks in each of the first five generations after an accident and include information on the relative severity of various classes of genetic effects. The uncertainty in modeloling radiological health risks is addressed by providing central, upper, and lower estimates of risks. An approach is outlined for summarizing the health consequences of nuclear power plant accidents. 298 refs., 9 figs., 49 tabs

  19. Placebo Response is Driven by UCS Revaluation: Evidence, Neurophysiological Consequences and a Quantitative Model.

    Science.gov (United States)

    Puviani, Luca; Rama, Sidita

    2016-07-20

    Despite growing scientific interest in the placebo effect and increasing understanding of neurobiological mechanisms, theoretical modeling of the placebo response remains poorly developed. The most extensively accepted theories are expectation and conditioning, involving both conscious and unconscious information processing. However, it is not completely understood how these mechanisms can shape the placebo response. We focus here on neural processes which can account for key properties of the response to substance intake. It is shown that placebo response can be conceptualized as a reaction of a distributed neural system within the central nervous system. Such a reaction represents an integrated component of the response to open substance administration (or to substance intake) and is updated through "unconditioned stimulus (UCS) revaluation learning". The analysis leads to a theorem, which proves the existence of two distinct quantities coded within the brain, these are the expected or prediction outcome and the reactive response. We show that the reactive response is updated automatically by implicit revaluation learning, while the expected outcome can also be modulated through conscious information processing. Conceptualizing the response to substance intake in terms of UCS revaluation learning leads to the theoretical formulation of a potential neuropharmacological treatment for increasing unlimitedly the effectiveness of a given drug.

  20. Consequences of a unified, anarchical model of fermion masses and mixings

    International Nuclear Information System (INIS)

    Calibbi, L.; Ferretti, L.; Romanino, A.; Ziegler, R.

    2009-01-01

    We show that most features of the mass and mixing pattern of the second and third SM fermion families can be accounted for without making use of flavour symmetries or other types of flavour dynamics. We discuss the implications for flavour phenomenology, in particular for the τ → μγ decay rate, and comment on LFV effects at colliders. We show that the model can be embedded in a full SO(10) supersymmetric GUT in 5 dimensions that preserves the successful MSSM gauge coupling unification prediction for α s . Interesting features of this embedding are i) the connection of one of the hierarchy parameters with the strong coupling assumption, ii) the absence of KK threshold effects on the α s prediction at one loop, and iii) the shift of the GUT scale up to about 10 17 GeV. Proton decay is under control, also due to the larger GUT scale. A large atmospheric angle for normal hierarchical neutrinos is obtained in an unusual way.

  1. Collapsing Factors in Multitrait-Multimethod Models: Examining Consequences of a Mismatch Between Measurement Design and Model

    Directory of Open Access Journals (Sweden)

    Christian eGeiser

    2015-08-01

    Full Text Available Models of confirmatory factor analysis (CFA are frequently applied to examine the convergent validity of scores obtained from multiple raters or methods in so-called multitrait-multimethod (MTMM investigations. Many applications of CFA-MTMM and similarly structured models result in solutions in which at least one method (or specific factor shows non-significant loading or variance estimates. Eid et al. (2008 distinguished between MTMM measurement designs with interchangeable (randomly selected versus structurally different (fixed methods and showed that each type of measurement design implies specific CFA-MTMM measurement models. In the current study, we hypothesized that some of the problems that are commonly seen in applications of CFA-MTMM models may be due to a mismatch between the underlying measurement design and fitted models. Using simulations, we found that models with M method factors (where M is the total number of methods and unconstrained loadings led to a higher proportion of solutions in which at least one method factor became empirically unstable when these models were fit to data generated from structurally different methods. The simulations also revealed that commonly used model goodness-of-fit criteria frequently failed to identify incorrectly specified CFA-MTMM models. We discuss implications of these findings for other complex CFA models in which similar issues occur, including nested (bifactor and latent state-trait models.

  2. A review of {sup 137}Cs transfer to fungi and consequences for modelling environmental transfer

    Energy Technology Data Exchange (ETDEWEB)

    Gillett, A.G. E-mail: andy.gillett@nottingham.ac.uk; Crout, N.M.J

    2000-03-01

    A review of the published literature describing {sup 137}Cs transfer to fungi was carried out, summarising the collated data to determine factors controlling transfer and identify an appropriate modelling approach to predict future contamination. {sup 137}Cs transfer ratios (TR) are derived for fungi species collected within Europe and the CIS. Considerable variability in TRs is demonstrated, with TRs varying between <0.001 and >10 m{sup 2} kg{sup -1} across all species and over three orders of magnitude for individual species (e.g. Boletus badius). Generally, meta-information (such as habitat and soil attributes) is poorly reported in the literature so that classification of the TR is limited to the effect of nutritional type (P<0.025) in the order mycorrhizal>saprophytic{approx}parasitic. Analysis of the literature data set (a heterogeneous source) suggests that there is no statistical evidence to indicate a decrease in TRs for 10 years after the Chernobyl accident. Spatial analysis of a data set for Belgium indicates variability in {sup 137}Cs transfer within a sampling location, such that fruitbodies collected over a scale of approximately 5 km would show activities as variable as those collected over a much larger scale ({approx} or>50 km). Therefore, it is proposed that the collated data sets for individual species can be used to derive 'best estimates' for the parameters describing the distribution of TRs. These can then be used to estimate an 'effective' TR, which, when combined with local soil deposition level and frequency and effect of culinary practices, can give an estimate of the activity of fungi consumed by the general population.

  3. Sex hormones affect acute and chronic stress responses in sexually dimorphic patterns: Consequences for depression models.

    Science.gov (United States)

    Guo, Lei; Chen, Yi-Xi; Hu, Yu-Ting; Wu, Xue-Yan; He, Yang; Wu, Juan-Li; Huang, Man-Li; Mason, Matthew; Bao, Ai-Min

    2018-05-21

    Alterations in peripheral sex hormones may play an important role in sex differences in terms of stress responses and mood disorders. It is not yet known whether and how stress-related brain systems and brain sex steroid levels fluctuate in relation to changes in peripheral sex hormone levels, or whether the different sexes show different patterns. We aimed to investigate systematically, in male and female rats, the effect of decreased circulating sex hormone levels following gonadectomy on acute and chronic stress responses, manifested as changes in plasma and hypothalamic sex steroids and hypothalamic stress-related molecules. Experiment (Exp)-1: Rats (14 males, 14 females) were gonadectomized or sham-operated (intact); Exp-2: gonadectomized and intact rats (28 males, 28 females) were exposed to acute foot shock or no stressor; and Exp-3: gonadectomized and intact rats (32 males, 32 females) were exposed to chronic unpredictable mild stress (CUMS) or no stressor. For all rats, plasma and hypothalamic testosterone (T), estradiol (E2), and the expression of stress-related molecules were determined, including corticotropin-releasing hormone, vasopressin, oxytocin, aromatase, and the receptors for estrogens, androgens, glucocorticoids, and mineralocorticoids. Surprisingly, no significant correlation was observed in terms of plasma sex hormones, brain sex steroids, and hypothalamic stress-related molecule mRNAs (p > 0.113) in intact or gonadectomized, male or female, rats. Male and female rats, either intact or gonadectomized and exposed to acute or chronic stress, showed different patterns of stress-related molecule changes. Diminished peripheral sex hormone levels lead to different peripheral and central patterns of change in the stress response systems in male and female rats. This has implications for the choice of models for the study of the different types of mood disorders which also show sex differences. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Economic consequences of paratuberculosis control in dairy cattle: A stochastic modeling study.

    Science.gov (United States)

    Smith, R L; Al-Mamun, M A; Gröhn, Y T

    2017-03-01

    The cost of paratuberculosis to dairy herds, through decreased milk production, early culling, and poor reproductive performance, has been well-studied. The benefit of control programs, however, has been debated. A recent stochastic compartmental model for paratuberculosis transmission in US dairy herds was modified to predict herd net present value (NPV) over 25 years in herds of 100 and 1000 dairy cattle with endemic paratuberculosis at initial prevalence of 10% and 20%. Control programs were designed by combining 5 tests (none, fecal culture, ELISA, PCR, or calf testing), 3 test-related culling strategies (all test-positive, high-positive, or repeated positive), 2 test frequencies (annual and biannual), 3 hygiene levels (standard, moderate, or improved), and 2 cessation decisions (testing ceased after 5 negative whole-herd tests or testing continued). Stochastic dominance was determined for each herd scenario; no control program was fully dominant for maximizing herd NPV in any scenario. Use of the ELISA test was generally preferred in all scenarios, but no paratuberculosis control was highly preferred for the small herd with 10% initial prevalence and was frequently preferred in other herd scenarios. Based on their effect on paratuberculosis alone, hygiene improvements were not found to be as cost-effective as test-and-cull strategies in most circumstances. Global sensitivity analysis found that economic parameters, such as the price of milk, had more influence on NPV than control program-related parameters. We conclude that paratuberculosis control can be cost effective, and multiple control programs can be applied for equivalent economic results. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. A review of 137Cs transfer to fungi and consequences for modelling environmental transfer

    International Nuclear Information System (INIS)

    Gillett, A.G.; Crout, N.M.J.

    2000-01-01

    A review of the published literature describing 137 Cs transfer to fungi was carried out, summarising the collated data to determine factors controlling transfer and identify an appropriate modelling approach to predict future contamination. 137 Cs transfer ratios (TR) are derived for fungi species collected within Europe and the CIS. Considerable variability in TRs is demonstrated, with TRs varying between 10 m 2 kg -1 across all species and over three orders of magnitude for individual species (e.g. Boletus badius). Generally, meta-information (such as habitat and soil attributes) is poorly reported in the literature so that classification of the TR is limited to the effect of nutritional type (P saprophytic∼parasitic. Analysis of the literature data set (a heterogeneous source) suggests that there is no statistical evidence to indicate a decrease in TRs for 10 years after the Chernobyl accident. Spatial analysis of a data set for Belgium indicates variability in 137 Cs transfer within a sampling location, such that fruitbodies collected over a scale of approximately 5 km would show activities as variable as those collected over a much larger scale (∼ or>50 km). Therefore, it is proposed that the collated data sets for individual species can be used to derive 'best estimates' for the parameters describing the distribution of TRs. These can then be used to estimate an 'effective' TR, which, when combined with local soil deposition level and frequency and effect of culinary practices, can give an estimate of the activity of fungi consumed by the general population

  6. School District Personnel Selection Practices: Exploring the Effects of Demographic Factors on Rural Values within a Person-Organization Fit Model.

    Science.gov (United States)

    Little, Paula S.; Miller, Stephen K.

    A study examined the extent to which demographic factors predict rural values in Kentucky public school district hiring officials. Among the demographic factors considered were school district metropolitan classification, school district size, community racial composition, decision makers' position in the organizational hierarchy, and decision…

  7. Health effects models for nuclear power plant accident consequence analysis. Part 1, Introduction, integration, and summary: Revision 2

    Energy Technology Data Exchange (ETDEWEB)

    Evans, J.S. [Harvard School of Public Health, Boston, MA (United States); Abrahmson, S. [Wisconsin Univ., Madison, WI (United States); Bender, M.A. [Brookhaven National Lab., Upton, NY (United States); Boecker, B.B.; Scott, B.R. [Inhalation Toxicology Research Inst., Albuquerque, NM (United States); Gilbert, E.S. [Battelle Pacific Northwest Lab., Richland, WA (United States)

    1993-10-01

    This report is a revision of NUREG/CR-4214, Rev. 1, Part 1 (1990), Health Effects Models for Nuclear Power Plant Accident Consequence Analysis. This revision has been made to incorporate changes to the Health Effects Models recommended in two addenda to the NUREG/CR-4214, Rev. 1, Part 11, 1989 report. The first of these addenda provided recommended changes to the health effects models for low-LET radiations based on recent reports from UNSCEAR, ICRP and NAS/NRC (BEIR V). The second addendum presented changes needed to incorporate alpha-emitting radionuclides into the accident exposure source term. As in the earlier version of this report, models are provided for early and continuing effects, cancers and thyroid nodules, and genetic effects. Weibull dose-response functions are recommended for evaluating the risks of early and continuing health effects. Three potentially lethal early effects -- the hematopoietic, pulmonary, and gastrointestinal syndromes are considered. Linear and linear-quadratic models are recommended for estimating the risks of seven types of cancer in adults - leukemia, bone, lung, breast, gastrointestinal, thyroid, and ``other``. For most cancers, both incidence and mortality are addressed. Five classes of genetic diseases -- dominant, x-linked, aneuploidy, unbalanced translocations, and multifactorial diseases are also considered. Data are provided that should enable analysts to consider the timing and severity of each type of health risk.

  8. Review of models used for determining consequences of UF6 release: Development of model evaluation criteria. Volume 1

    International Nuclear Information System (INIS)

    Nair, S.K.; Chambers, D.B.; Park, S.H.; Hoffman, F.O.

    1997-11-01

    The objective of this study is to examine the usefulness and effectiveness of currently existing models that simulate the release of uranium hexafluoride from UF 6 -handling facilities, subsequent reactions of UF 6 with atmospheric moisture, and the dispersion of UF 6 and reaction products in the atmosphere. The study evaluates screening-level and detailed public-domain models that were specifically developed for UF 6 and models that were originally developed for the treatment of dense gases but are applicable to UF 6 release, reaction, and dispersion. The model evaluation process is divided into three specific tasks: model-component evaluation; applicability evaluation; and user interface and quality assurance and quality control (QA/QC) evaluation. Within the model-component evaluation process, a model's treatment of source term, thermodynamics, and atmospheric dispersion are considered and model predictions are compared with actual observations. Within the applicability evaluation process, a model's applicability to Integrated Safety Analysis, Emergency Response Planning, and Post-Accident Analysis, and to site-specific considerations are assessed. Finally, within the user interface and QA/QC evaluation process, a model's user-friendliness, presence and clarity of documentation, ease of use, etc. are assessed, along with its handling of QA/QC. This document presents the complete methodology used in the evaluation process

  9. Review of models used for determining consequences of UF{sub 6} release: Model evaluation report. Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Nair, S.K.; Chambers, D.B.; Park, S.H.; Radonjic, Z.R.; Coutts, P.T.; Lewis, C.J.; Hammonds, J.S.; Hoffman, F.O. [Senes Oak Ridge, Inc., TN (United States). Center for Risk Analysis

    1997-11-01

    Three uranium hexafluoride-(UF{sub 6}-) specific models--HGSYSTEM/UF{sub 6}, Science Application International Corporation, and RTM-96; three dense-gas models--DEGADIS, SLAB, and the Chlorine Institute methodology; and one toxic chemical model--AFTOX--are evaluated on their capabilities to simulate the chemical reactions, thermodynamics, and atmospheric dispersion of UF{sub 6} released from accidents at nuclear fuel-cycle facilities, to support Integrated Safety Analysis, Emergency Response Planning, and Post-Accident Analysis. These models are also evaluated for user-friendliness and for quality assurance and quality control features, to ensure the validity and credibility of the results. Model performance evaluations are conducted for the three UF{sub 6}-specific models, using field data on releases of UF{sub 6} and other heavy gases. Predictions from the HGSYSTEM/UF{sub 6} and SAIC models are within an order of magnitude of the field data, but the SAIC model overpredicts beyond an order of magnitude for a few UF{sub 6}-specific data points. The RTM-96 model provides overpredictions within a factor of 3 for all data points beyond 400 m from the source. For one data set, however, the RTM-96 model severely underpredicts the observations within 200 m of the source. Outputs of the models are most sensitive to the meteorological parameters at large distances from the source and to certain source-specific and meteorological parameters at distances close to the source. Specific recommendations are being made to improve the applicability and usefulness of the three models and to choose a specific model to support the intended analyses. Guidance is also provided on the choice of input parameters for initial dilution, building wake effects, and distance to completion of UF{sub 6} reaction with water.

  10. Ion irradiation to simulate neutron irradiation in model graphites: Consequences for nuclear graphite

    Science.gov (United States)

    Galy, N.; Toulhoat, N.; Moncoffre, N.; Pipon, Y.; Bérerd, N.; Ammar, M. R.; Simon, P.; Deldicque, D.; Sainsot, P.

    2017-10-01

    Due to its excellent moderator and reflector qualities, graphite was used in CO2-cooled nuclear reactors such as UNGG (Uranium Naturel-Graphite-Gaz). Neutron irradiation of graphite resulted in the production of 14C which is a key issue radionuclide for the management of the irradiated graphite waste. In order to elucidate the impact of neutron irradiation on 14C behavior, we carried out a systematic investigation of irradiation and its synergistic effects with temperature in Highly Oriented Pyrolitic Graphite (HOPG) model graphite used to simulate the coke grains of nuclear graphite. We used 13C implantation in order to simulate 14C displaced from its original structural site through recoil. The collision of the impinging neutrons with the graphite matrix carbon atoms induces mainly ballistic damage. However, a part of the recoil carbon atom energy is also transferred to the graphite lattice through electronic excitation. The effects of the different irradiation regimes in synergy with temperature were simulated using ion irradiation by varying Sn(nuclear)/Se(electronic) stopping power. Thus, the samples were irradiated with different ions of different energies. The structure modifications were followed by High Resolution Transmission Electron Microscopy (HRTEM) and Raman microspectrometry. The results show that temperature generally counteracts the disordering effects of irradiation but the achieved reordering level strongly depends on the initial structural state of the graphite matrix. Thus, extrapolating to reactor conditions, for an initially highly disordered structure, irradiation at reactor temperatures (200 - 500 °C) should induce almost no change of the initial structure. On the contrary, when the structure is initially less disordered, there should be a "zoning" of the reordering: In "cold" high flux irradiated zones where the ballistic damage is important, the structure should be poorly reordered; In "hot" low flux irradiated zones where the ballistic

  11. Serbian demographers on demography

    Directory of Open Access Journals (Sweden)

    Rašević Mirjana

    2013-01-01

    Full Text Available Introduction: The objective of this paper is to collect the opinions of the leading demographers in Serbia on four significant matters. The matters are: development, state and future of demography, the successfulness of researchers in this scientific discipline, improvement of the Stanovništvo journal, as well as the population priority of our society and range of population policies. Method: A qualitative interview was chosen as the instrument for data collection. Namely, a structured interview, based on nine questions was sent by e-mail to eleven addresses of relevant demographers in the second half of October 2013. The basic reason for sending questions by e-mail was the aspiration to obtain authentic replies which require time for contemplation. Ten completed questionnaires were returned within two weeks. On the one hand, an integral picture on the chosen themes for research was attempted to be obtained in the analysis of received opinions to certain groups of questions and on the other hand to portray the spectrum of different observations. The responses of our prominent demographers were analyzed and compared to clearly pronounced standpoints of eminent demographers published in world journals on similar themes and with findings of internet researches among members of the International Union for the Scientific Study of Population. Results: The results show that there is a high level of consent among demographers in Serbia regarding the well positioning of demography in relation to other social studies and its good perspectives. The interviewed experts see the future of demography in its integration with a wide circle of sciences, the application of demography and/or greater engagement of researchers in carrying out public policies. However, the estimations of the interviewed demographers as regards the development and state of demography in Serbia are divided. Although a large number of topics had been listed, migrations and population

  12. Find the weakest link. A comparison between demographic, genetic and demo-genetic metapopulation extinction times

    Directory of Open Access Journals (Sweden)

    Robert Alexandre

    2011-09-01

    Full Text Available Abstract Background While the ultimate causes of most species extinctions are environmental, environmental constraints have various secondary consequences on evolutionary and ecological processes. The roles of demographic, genetic mechanisms and their interactions in limiting the viabilities of species or populations have stirred much debate and remain difficult to evaluate in the absence of demography-genetics conceptual and technical framework. Here, I computed projected times to metapopulation extinction using (1 a model focusing on the effects of species properties, habitat quality, quantity and temporal variability on the time to demographic extinction; (2 a genetic model focusing on the dynamics of the drift and inbreeding loads under the same species and habitat constraints; (3 a demo-genetic model accounting for demographic-genetic processes and feedbacks. Results Results indicate that a given population may have a high demographic, but low genetic viability or vice versa; and whether genetic or demographic aspects will be the most limiting to overall viability depends on the constraints faced by the species (e.g., reduction of habitat quantity or quality. As a consequence, depending on metapopulation or species characteristics, incorporating genetic considerations to demographically-based viability assessments may either moderately or severely reduce the persistence time. On the other hand, purely genetically-based estimates of species viability may either underestimate (by neglecting demo-genetic interactions or overestimate (by neglecting the demographic resilience true viability. Conclusion Unbiased assessments of the viabilities of species may only be obtained by identifying and considering the most limiting processes (i.e., demography or genetics, or, preferentially, by integrating them.

  13. Consequence analysis

    International Nuclear Information System (INIS)

    Woodard, K.

    1985-01-01

    The objectives of this paper are to: Provide a realistic assessment of consequences; Account for plant and site-specific characteristics; Adjust accident release characteristics to account for results of plant-containment analysis; Produce conditional risk curves for each of five health effects; and Estimate uncertainties

  14. A Development of Domestic Food Chain Model Data for Chronic Effect Estimation of Off-site Consequence Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Han, Seok-Jung; KEUM, Dong-Kwon; Jang, Seung-Cheol [KAERI, Daejeon (Korea, Republic of)

    2015-05-15

    The FCM includes complex transport phenomena of radiation materials on a biokinetic system of contaminated environments. An estimation of chronic health effects is a key part of the level 3 PSA (Probabilistic Safety Assessment), which depends on the FCM estimation from contaminated foods ingestion. A cultural ingestion habit of a local region and agricultural productions are different to the general features over worldwide scale or case by case. This is a reason to develop a domestic FCM data for the level 3 PSA. However, a generation of the specific FCM data is a complex process and under a large degree of uncertainty due to inherent biokinetic models. As a preliminary study, the present study focuses on an infrastructure development to generation of a specific FCM data. During this process, the features of FCM data to generate a domestic FCM data were investigated. Based on the insights obtained from this process, a specific domestic FCM data was developed. The present study was developed a domestic FCM data to estimate the chronic health effects of off-site consequence analysis. From this study, an insight was obtained, that a domestic FCM data is roughly 20 times higher than the MACCS2 defaults data. Based on this observation, it is clear that the specific chronic health effects of a domestic plant site should be considered in the off-site consequence analysis.

  15. A Development of Domestic Food Chain Model Data for Chronic Effect Estimation of Off-site Consequence Analysis

    International Nuclear Information System (INIS)

    Han, Seok-Jung; KEUM, Dong-Kwon; Jang, Seung-Cheol

    2015-01-01

    The FCM includes complex transport phenomena of radiation materials on a biokinetic system of contaminated environments. An estimation of chronic health effects is a key part of the level 3 PSA (Probabilistic Safety Assessment), which depends on the FCM estimation from contaminated foods ingestion. A cultural ingestion habit of a local region and agricultural productions are different to the general features over worldwide scale or case by case. This is a reason to develop a domestic FCM data for the level 3 PSA. However, a generation of the specific FCM data is a complex process and under a large degree of uncertainty due to inherent biokinetic models. As a preliminary study, the present study focuses on an infrastructure development to generation of a specific FCM data. During this process, the features of FCM data to generate a domestic FCM data were investigated. Based on the insights obtained from this process, a specific domestic FCM data was developed. The present study was developed a domestic FCM data to estimate the chronic health effects of off-site consequence analysis. From this study, an insight was obtained, that a domestic FCM data is roughly 20 times higher than the MACCS2 defaults data. Based on this observation, it is clear that the specific chronic health effects of a domestic plant site should be considered in the off-site consequence analysis

  16. Population Ageing and the Theory of Demographic Transition: The ...

    African Journals Online (AJOL)

    Population Ageing and the Theory of Demographic Transition: The Case of Mauritius. ... the life expectancy of the population and consequently, the society is ageing. ... Originality/Value – Although some studies have been done on ageing yet ...

  17. Demographic Change and Transport

    DEFF Research Database (Denmark)

    Haustein, Sonja; Siren, Anu Kristiina; Framke, Elisabeth

    This report is the literature review on demographic changes and transport of Work Package 1 of the EU project CONSOL, “CONcerns and SOLutions – Road Safety in the Ageing Societies” (contract period: 2011-2013). The report is a state-of-the art report that combines current knowledge with new...

  18. Country Demographic Profiles: Thailand.

    Science.gov (United States)

    Bureau of the Census (DOC), Suitland, MD. Population Div.

    This profile of the population of Thailand contains 35 tables of selected demographic information, including size of population and estimates of fertility and mortality, beginning in 1950. An adjusted distribution of the population by age and sex is given for the latest census year, as well as for 1976. Projections of the number of women of…

  19. Assessment of off-site consequences of nuclear accidents (MARIA)

    International Nuclear Information System (INIS)

    Haywood, S.M.

    1985-01-01

    A brief report is given of a workshop held in Luxembourg in 1985 on methods for assessing the off-site radiological consequences of nuclear accidents (MARIA). The sessions included topics such as atmospheric dispersion; foodchain transfer; urban contamination; demographic and land use data; dosimetry, health effects, economic and countermeasures models; uncertainty analysis; and application of probabilistic risk assessment results as input to decision aids. (U.K.)

  20. Optimum modellings of atmospheric diffusion of radioactive effluents and exposure doses in the accident consequence assessment (Level 3 PSA)

    International Nuclear Information System (INIS)

    Kim, Byung Woo; Lee, Young Bok; Han, Moon Hee; Kim, Eun Han; Suh, Kyung Suk; Hwang, Won Tae

    1992-12-01

    Atmospheric diffusion and exposure strongly dependent on the environment were firstly considered in the full spectrum of accident consequence assessment to establish based on Korean conditions. An optimum weather category based on Korean climate and site-specific meteorology of Kori region was established by statistical analysis of measured data for 10 years. And a trajectory model was selected as the optimal one in the ACA by reviewing several existing diffusion models. Following aspects were considered in this selection as availability of meteorological data, ability to treat the change to wind direction, easy applicability of the model, and restriction of CPU time and core memory in current computers. Numerical integration method of our own was selected as the optimal dose assessment tool of external exposure. Unit dose rate was firstly computed with this method as the function of energy level of radionuclide, size of lattice, and distance between source and receptor, and then the results were rearranged as the data library for the rapid access to the ACA run. Dynamic ecosystem modelling has been done in order to estimate the seasonal variation of radioactivity for the assessment of ingestion exposure, considering Korean ingestion behavior, agricultural practice and the transportation. There is a lot of uncertainty in a countermeasure model due to the assumed values of parameters such as fraction of population with different shielding factor and driving speed. A new countermeasure model was developed using the concept of fuzzy set theory, since it provided the mathematical tools which could characterize the uncertainty involved in countermeasure modelling. (Author)

  1. Economic consequences of the Swiss 'Strom ohne Atom' and 'Moratorium Plus' popular initiatives - Analysis using a balanced model

    International Nuclear Information System (INIS)

    Mueller, A.; Wickart, M.; Van Nieuwkoop, R.

    2001-01-01

    This article is a short version of the ENET number 210359. This report for the Swiss Federal Office of Energy (SFOE) presents the results of a study made to assess the economic consequences of two models for the opting out of nuclear energy in Switzerland, as proposed in two popular initiatives. The 'Strom ohne Atom' (electricity without atomic power) initiative calls for the shutting down of the existing nuclear power stations and the 'Moratorium Plus' initiative calls for a stop on the building of new atomic power stations for 10 years. The method used for assessing the costs and benefits resulting if the initiatives were accepted in a public vote is described. Basic assumptions made on further factors concerning the electricity and energy markets are discussed. Results of analyses made for various scenarios with respect to CO 2 emissions are presented and include discussions on risk costs, effects on employment and welfare aspects

  2. Economic consequences of the Swiss 'Strom ohne Atom' and 'Moratorium Plus' popular initiatives - Analysis using a balanced model

    International Nuclear Information System (INIS)

    Mueller, A.; Wickart, M.; Van Nieuwkoop, R.

    2001-01-01

    This report for the Swiss Federal Office of Energy (SFOE) presents the results of a study made to assess the economic consequences of two models for the opting out of nuclear energy in Switzerland, as proposed in two popular initiatives. The 'Strom ohne Atom' (electricity without atomic power) initiative calls for the shutting down of the existing nuclear power stations and the 'Moratorium Plus' initiative calls for a stop on the building of new atomic power stations for 10 years. The method used for assessing the costs and benefits resulting if the initiatives were accepted in a public vote is described. Basic assumptions made on further factors concerning the electricity and energy markets are discussed. Results of analyses made for various scenarios with respect to CO 2 emissions are presented and include discussions on risk costs, effects on employment and welfare aspects

  3. User's guide to MARINRAD: model for assessing the consequences of release of radioactive material into the oceans

    International Nuclear Information System (INIS)

    Koplik, C.M.; Kaplan, M.F.; Nalbandian, J.Y.; Simonson, J.H.; Clark, P.G.

    1984-05-01

    Marine Radionuclide Transport and Dose (MARINRAD) is a system of the computer programs designed to evaluate the consequences from release of radioactive waste into the ocean. The FORTRAN program MARRAD, which is part of the MARINRAD software, computes nuclide concentration caused by ocean transport and generates food chain concentration factors. The FORTRAN program MAROUT, which is also part of MARINRAD, evaluates a pathways-to-man dose model, generates print reports, and produces graphic plots. MARINRAD's top-down modular design provides flexible software that can be easily modified for a user's specific problem. MARINRAD was developed under contract with the Sandia National Laboratories in Albuquerque, New Mexico. 18 references, 23 figures, 42 tables

  4. Economic consequences of the Swiss 'Sortir du nucleaire' and 'Moratoire-plus' popular initiatives - Analysis using a balanced model

    International Nuclear Information System (INIS)

    Mueller, A.; Wickart, M.; Van Nieuwkoop, R.

    2001-01-01

    This article is a short version of the ENET number 210359. This report for the Swiss Federal Office of Energy (SFOE) presents the results of a study made to assess the economic consequences of two models for the opting out of nuclear energy in Switzerland, as proposed in two popular initiatives. The 'Sortir du nucleaire' (electricity without atomic power) initiative calls for the shutting down of the existing nuclear power stations and the 'Moratoire-plus' initiative calls for a stop on the building of new atomic power stations for 10 years. The method used for assessing the costs and benefits resulting if the initiatives were accepted in a public vote is described. Basic assumptions made on further factors concerning the electricity and energy markets are discussed. Results of analyses made for various scenarios with respect to CO 2 emissions are presented and include discussions on risk costs, effects on employment and welfare aspects

  5. Consequences of increasing bioenergy demand on wood and forests: An application of the Global Forest Products Model

    Science.gov (United States)

    Buongiorno, J.; Raunikar, R.; Zhu, S.

    2011-01-01

    The Global Forest Products Model (GFPM) was applied to project the consequences for the global forest sector of doubling the rate of growth of bioenergy demand relative to a base scenario, other drivers being maintained constant. The results showed that this would lead to the convergence of the price of fuelwood and industrial roundwood, raising the price of industrial roundwood by nearly 30% in 2030. The price of sawnwood and panels would be 15% higher. The price of paper would be 3% higher. Concurrently, the demand for all manufactured wood products would be lower in all countries, but the production would rise in countries with competitive advantage. The global value added in wood processing industries would be 1% lower in 2030. The forest stock would be 2% lower for the world and 4% lower for Asia. These effects varied substantially by country. ?? 2011 Department of Forest Economics, SLU Ume??, Sweden.

  6. Consequences of Windscale accident (October 1957) and study of the validity of the Sutton's mathematical model of atmospheric diffusion (1960)

    International Nuclear Information System (INIS)

    Doury, A.

    1960-01-01

    The reactor accident that happens at the number 1 pile of Windscale in 1957 was followed by a discharge of radioactive products into the atmosphere from the 1.X.1957 at 4.30 PM to the 12.X.1957 at 3.10 PM. On october the 11 th it was possible to say that there was no more risk either of external irradiation or inhalation. But in adopting a M.A.C. of 0,1 μcurie of iodine 131 per litre of milk, the Authority had to control the milk delivery till november 23 rd on a 500 km 2 area. On the other hand, this exceptional accident permit to verify that Sutton's atmospheric diffusion model could give an easy means to foresee, with a sufficient approximation, the consequences of a dispersion of radioactive products into the atmosphere. (author) [fr

  7. Modelling the consequences of targeted selective treatment strategies on performance and emergence of anthelmintic resistance amongst grazing calves

    Directory of Open Access Journals (Sweden)

    Zoe Berk

    2016-12-01

    Full Text Available The development of anthelmintic resistance by helminths can be slowed by maintaining refugia on pasture or in untreated hosts. Targeted selective treatments (TST may achieve this through the treatment only of individuals that would benefit most from anthelmintic, according to certain criteria. However TST consequences on cattle are uncertain, mainly due to difficulties of comparison between alternative strategies. We developed a mathematical model to compare: 1 the most ‘beneficial’ indicator for treatment selection and 2 the method of selection of calves exposed to Ostertagia ostertagi, i.e. treating a fixed percentage of the population with the lowest (or highest indicator values versus treating individuals who exceed (or are below a given indicator threshold. The indicators evaluated were average daily gain (ADG, faecal egg counts (FEC, plasma pepsinogen, combined FEC and plasma pepsinogen, versus random selection of individuals. Treatment success was assessed in terms of benefit per R (BPR, the ratio of average benefit in weight gain to change in frequency of resistance alleles R (relative to an untreated population. The optimal indicator in terms of BPR for fixed percentages of calves treated was plasma pepsinogen and the worst ADG; in the latter case treatment was applied to some individuals who were not in need of treatment. The reverse was found when calves were treated according to threshold criteria, with ADG being the best target indicator for treatment. This was also the most beneficial strategy overall, with a significantly higher BPR value than any other strategy, but its degree of success depended on the chosen threshold of the indicator. The study shows strong support for TST, with all strategies showing improvements on calves treated selectively, compared with whole-herd treatment at 3, 8, 13 weeks post-turnout. The developed model appeared capable of assessing the consequences of other TST strategies on calf populations.

  8. Cause of death during 2009–2012, using a probabilistic model (InterVA-4: an experience from Ballabgarh Health and Demographic Surveillance System in India

    Directory of Open Access Journals (Sweden)

    Sanjay K. Rai

    2014-10-01

    Full Text Available Objectives: The present study aimed to estimate the age and cause-specific mortality in Ballabgarh Health and Demographic Surveillance System (HDSS site for the years 2009 to 2012, using a probabilistic model (InterVA-4. Methods: All Deaths in Ballabgarh HDSS from January 1, 2009, to December 31, 2012, were included in the study. InterVA-4 model (version 4.02 was used for assigning cause of death (COD. Data from the verbal autopsy (VA tool were extracted and processed with the InterVA-4 model. Cause-specific mortality rate (CSMR per 1,000 person-years was calculated. Results: A total of 2,459 deaths occurred in the HDSS during the year 2009 to 2012. Among them, 2,174 (88.4% valid VA interviews were conducted. Crude death rate ranged from 7.1 (2009 to 6.4 (2012 per 1,000 population. The CSMR per 1,000 person-years over the years (2009–2012 for non-communicable diseases, communicable diseases, trauma, neoplasm, and maternal and neonatal diseases were 1.78, 1.68, 0.68, 0.49, and 0.48, respectively. The most common causes of death among children, adults, and the elderly were infectious diseases, trauma, and non-communicable diseases, respectively. Conclusions: Overall, non-communicable diseases constituted the largest proportion of mortality, whereas trauma was the most common COD among adults at Ballabgarh HDSS. Policy-makers ought to focus on prevention of premature CODs, especially prevention of infectious diseases in children, and intentional self-harm and road traffic accidents in the adult population.

  9. Experts Networks and the European Commission on Demographic Change

    DEFF Research Database (Denmark)

    Seabrooke, Leonard; Tsingou, Eleni; Willers, Johann Ole

    experts on demographic change. Our findings suggest that on demographic change issues at the EU level, DG EMPL has taken the lead, while DG ECFIN is the secondary actor. Still, internal European Commission dynamics mean that the lead actor on demographic issues has less autonomy in articulating a funded......This paper examines who populates the expert and policy network around demographic change issues in Europe. We examine how competing policy departments in the European Commission Directorates-General (DGs) deal with the issue of Europe’s changing demography, as well as discuss the role of external...... and clear policy position on how to address them. As a consequence, there is little institutional memory and hardly a depository of activity on demographic change. While outside expertise comes primarily from demographers, and other scholars concerned with demographic change, they are primarily an academic...

  10. EJSCREEN Demographic Indicators 2015 Public

    Science.gov (United States)

    EJSCREEN uses demographic factors as very general indicators of a community's potential susceptibility to the types of environmental factors included in this screening tool. There are six demographic indicators: Demographic Index, Supplementary Demographic Index, Individuals under Age 5, Individuals over Age 64, Percent Low-Income, Linguistic Isolation, Percent Minority, and Less than High School Education.

  11. Model review and evaluation for application in DOE safety basis documentation of chemical accidents - modeling guidance for atmospheric dispersion and consequence assessment

    Energy Technology Data Exchange (ETDEWEB)

    Lazaro, M. A. [Argonne National Lab. (ANL), Argonne, IL (United States); Woodarad, K. [Argonne National Lab. (ANL), Argonne, IL (United States); Hanna, S. R. [Argonne National Lab. (ANL), Argonne, IL (United States); Hesse, D. J. [Argonne National Lab. (ANL), Argonne, IL (United States); Huang, J. -C. [Argonne National Lab. (ANL), Argonne, IL (United States); Lewis, J. [Argonne National Lab. (ANL), Argonne, IL (United States); Mazzola, C. A. [Argonne National Lab. (ANL), Argonne, IL (United States)

    1997-09-01

    The U.S. Department of Energy (DOE), through its Defense Programs (DP), Office of Engineering and Operations Suppon, established the Accident Phenomenology and Consequence (AP AC) Methodology Evaluation Program to identify and evaluate methodologies and computer codes to support accident phenomenological and consequence calculations for both radiological and nonradiological materials at DOE facilities and to identify development needs. The program is also intended to define and recommend "best or good engineering/safety analysis practices" to be followed in preparing ''design or beyond design basis" assessments to be included in DOE nuclear and nonnuclear facility safety documents. The AP AC effort is intended to provide scientifically sound and more consistent analytical approaches, by identifying model selection procedures and application methodologies, in order to enhance safety analysis activities throughout the DOE complex.

  12. [Recent demographic trends].

    Science.gov (United States)

    1983-01-01

    A review of demographic trends in Luxembourg in 1982 is presented. A decline in fertility, the first since 1977, is noted, together with an increase in divorce, as well as a negative migration balance for the first time since 1967. Topics covered include natural increase and migration, fertility, marriage and divorce, mortality, adoption, and legislation affecting the family. Special consideration is given to the mortality experience of those who were subjected to compulsory labor during World War II.

  13. Radiological consequences of zinc-rich filter cake at Hoogovens Steel industry in IJmuiden, Netherlands (a modelled study)

    International Nuclear Information System (INIS)

    Laheij, G.M.H.; Eggink, G.J.

    1996-08-01

    In accordance with the revised Euratom 'basic safety standards', the Member States have to fill in the details of their own radiation protection policy on radionuclides from natural sources. In this framework the radiological consequences of zinc-rich filter cake at a storage facility of the steelplant Hoogovens Staal, in IJmuiden, Netherlands, were investigated in a model study. Also investigated were the consequences of possible transport of the filter cake to a storage facility in the country. The radiation dose was calculated for Hoogovens workers and for members of the population. For workers, the relevant exposure pathways are inhalation of resuspended filter cake, direct ingestion of filter cake and external radiation. Relevant exposure pathways for members of the population are inhalation of resuspended filter cake, ingestion of green vegetables on which resuspended filter cake is deposited and external radiation, which for workers at the storage facility the radiation dose is 7 mSv/a. The radiation dose for drivers during transport and for workers at a C3-storage facility depends strongly on whether the material is immobilized or not. The maximum radiation dose for both the transport and storage is expected to be almost equal to the radiation dose for workers at the storage facility at Hoogovens. For members of the population living around the storage facility at Hoogovens, the radiation dose is 3.6 mSv/a. Here too, the radiation dose at the storage facility depends strongly on whether the material is immobilized or not. During transport no radiation dose above the secondary level of 0.4 mSv/a is expected due to the short exposure times. 23 refs

  14. Review of the chronic exposure pathways models in MACCS [MELCOR Accident Consequence Code System] and several other well-known probabilistic risk assessment models

    International Nuclear Information System (INIS)

    Tveten, U.

    1990-06-01

    The purpose of this report is to document the results of the work performed by the author in connection with the following task, performed for US Nuclear Regulatory Commission, (USNRC) Office of Nuclear Regulatory Research, Division of Systems Research: MACCS Chronic Exposure Pathway Models: Review the chronic exposure pathway models implemented in the MELCOR Accident Consequence Code System (MACCS) and compare those models to the chronic exposure pathway models implemented in similar codes developed in countries that are members of the OECD. The chronic exposures concerned are via: the terrestrial food pathways, the water pathways, the long-term groundshine pathway, and the inhalation of resuspended radionuclides pathway. The USNRC has indicated during discussions of the task that the major effort should be spent on the terrestrial food pathways. There is one chapter for each of the categories of chronic exposure pathways listed above

  15. SOME CONSIDERATIONS ON THE DEMOGRAPHIC STRUCTURE OF MIGRANTS FROM BOTOSANI COUNTY

    Directory of Open Access Journals (Sweden)

    Petru BUNDUC

    2016-09-01

    Full Text Available This study aims to analyse the structural particularities of migrants in Botosani County, concerning the presentation model of the structure by age and sex. This is perhaps one of the most important elements in finding explanations and motivations of population leaving from county. However, demographic changes of this structure clearly present visible consequences such as increasing proportion of elderly people and reducing youth people, but also by reducing the active workforce.

  16. Radionuclide release, transport, and consequence modeling for WIPP: a report of a workshop held on September 16-17, 1981

    International Nuclear Information System (INIS)

    1982-02-01

    The purpose of this workshop was to discuss potential mechanisms for release of radionuclides from the WIPP repository years after waste emplacement and termination of institutional controls, and the resultant radiological consequences. Opportunity was also provided for the exchange of information on meaningful release and transport models, and the availability, reliability and significance of data for the parameters applicable to those models. Other than those scenarios provided in draft by the Environmental Evaluation Group (EEG) (Appendix II), there were no new breach scenarios postulated. Also there were no major objections posed to the EEG proposals or the approaches taken in these drafts. Although there were no formal conclusions highlighted by the Conference, the EEG has concluded that the statements below provide a summary of EEG's views concerning the topics covered. These views are based upon the discussions at the Conference, the subsequent comments of the conferees, the information provided in the preceding EEG sponsored geological meeting and field trip, and the information contained in the EEG draft reports

  17. Modelling lifetime cost consequences of toric compared with standard IOLs in cataract surgery of astigmatic patients in four European countries.

    Science.gov (United States)

    Laurendeau, C; Lafuma, A; Berdeaux, G

    2009-09-01

    To compare the lifetime costs of freeing astigmatic patients from spectacles after bilateral cataract surgery implanting toric intraocular lenses (IOLs: i.e., Acrysof Toric) versus monofocal IOLs, in France, Italy, Germany and Spain. A Markov model followed patient cohorts from cataract surgery until death. Prevalence rates of patients not needing spectacles and the types of spectacles prescribed for those requiring them were obtained from clinical trials and national surveys. The economic perspective was societal. Mortality rates were incorporated into the model. Discount rates were applied. A sensitivity analysis was performed on non-discounted costs. Fewer patients with toric IOLs needed spectacles for distance vision than patients with monofocal IOLs. With monofocal IOLs more than 66% of patients needed complex spectacles compared to less than 25% implanted with toric IOLs. In France and Italy, toric IOLs reduced overall costs relative to otherwise high spectacle costs after cataract surgery. Savings were 897.0 euros (France), 822.5 euros (Germany), 895.8 euros (Italy) and 391.6 euros (Spain), without discounting. On applying a 3% discount rate the costs became 691.7 euros, 646.4 euros, 693.9 euros and 308.2 euros, respectively. Bilateral toric IOL implants in astigmatic patients decreased spectacle dependence for distance vision and the need for complex spectacles. The economic consequences for patients depended on the national spectacle costs usually incurred after cataract surgery.

  18. Automated service quality and its behavioural consequences in CRM Environment: A structural equation modeling and causal loop diagramming approach

    Directory of Open Access Journals (Sweden)

    Arup Kumar Baksi

    2012-08-01

    Full Text Available Information technology induced communications (ICTs have revolutionized the operational aspects of service sector and have triggered a perceptual shift in service quality as rapid dis-intermediation has changed the access-mode of services on part of the consumers. ICT-enabled services further stimulated the perception of automated service quality with renewed dimensions and there subsequent significance to influence the behavioural outcomes of the consumers. Customer Relationship Management (CRM has emerged as an offshoot to technological breakthrough as it ensured service-encapsulation by integrating people, process and technology. This paper attempts to explore the relationship between automated service quality and its behavioural consequences in a relatively novel business-philosophy – CRM. The study has been conducted on the largest public sector bank of India - State bank of India (SBI at Kolkata which has successfully completed its decade-long operational automation in the year 2008. The study used structural equation modeling (SEM to justify the proposed model construct and causal loop diagramming (CLD to depict the negative and positive linkages between the variables.

  19. Choice & Consequence

    DEFF Research Database (Denmark)

    Khan, Azam

    to support hypothesis generation, hypothesis testing, and decision making. In addition to sensors in buildings, infrastructure, or the environment, we also propose the instrumentation of user interfaces to help measure performance in decision making applications. We show the benefits of applying principles...... between cause and effect in complex systems complicates decision making. To address this issue, we examine the central role that data-driven decision making could play in critical domains such as sustainability or medical treatment. We developed systems for exploratory data analysis and data visualization...... of data analysis and instructional interface design, to both simulation systems and decision support interfaces. We hope that projects such as these will help people to understand the link between their choices and the consequences of their decisions....

  20. The relative contributions of disease and insects in the decline of a long-lived tree: a stochastic demographic model of whitebark pine (Pinus albicaulis)

    Science.gov (United States)

    Jules, Erik S; Jackson, Jenell I.; van Mantgem, Phillip J.; Beck, Jennifer S.; Murray, Michael P.; Sahara, E. April

    2016-01-01

    Pathogens and insect pests have become increasingly important drivers of tree mortality in forested ecosystems. Unfortunately, understanding the relative contributions of multiple mortality agents to the population decline of trees is difficult, because it requires frequent measures of tree survival, growth, and recruitment, as well as the incidence of mortality agents. We present a population model of whitebark pine (Pinus albicaulis), a high-elevation tree undergoing rapid decline in western North America. The loss of whitebark pine is thought to be primarily due to an invasive pathogen (white pine blister rust; Cronartium ribicola) and a native insect (mountain pine beetle; Dendroctonus ponderosae). We utilized seven plots in Crater Lake National Park (Oregon, USA) where 1220 trees were surveyed for health and the presence of blister rust and beetle activity annually from 2003–2014, except 2008. We constructed size-based projection matrices for nine years and calculated the deterministic growth rate (λ) using an average matrix and the stochastic growth rate (λs) by simulation for whitebark pine in our study population. We then assessed the roles of blister rust and beetles by calculating λ and λsusing matrices in which we removed trees with blister rust and, separately, trees with beetles. We also conducted life-table response experiments (LTRE) to determine which demographic changes contributed most to differences in λ between ambient conditions and the two other scenarios. The model suggests that whitebark pine in our plots are currently declining 1.1% per year (λ = 0.9888, λs = 0.9899). Removing blister rust from the models resulted in almost no increase in growth (λ = 0.9916, λs = 0.9930), while removing beetles resulted in a larger increase in growth (λ = 1.0028, λs = 1.0045). The LTRE demonstrated that reductions in stasis of the three largest size classes due to beetles contributed most to the smaller λ in the ambient condition

  1. Global burden of sickle cell anaemia in children under five, 2010-2050: modelling based on demographics, excess mortality, and interventions.

    Directory of Open Access Journals (Sweden)

    Frédéric B Piel

    Full Text Available The global burden of sickle cell anaemia (SCA is set to rise as a consequence of improved survival in high-prevalence low- and middle-income countries and population migration to higher-income countries. The host of quantitative evidence documenting these changes has not been assembled at the global level. The purpose of this study is to estimate trends in the future number of newborns with SCA and the number of lives that could be saved in under-five children with SCA by the implementation of different levels of health interventions.First, we calculated projected numbers of newborns with SCA for each 5-y interval between 2010 and 2050 by combining estimates of national SCA frequencies with projected demographic data. We then accounted for under-five mortality (U5m projections and tested different levels of excess mortality for children with SCA, reflecting the benefits of implementing specific health interventions for under-five patients in 2015, to assess the number of lives that could be saved with appropriate health care services. The estimated number of newborns with SCA globally will increase from 305,800 (confidence interval [CI]: 238,400-398,800 in 2010 to 404,200 (CI: 242,500-657,600 in 2050. It is likely that Nigeria (2010: 91,000 newborns with SCA [CI: 77,900-106,100]; 2050: 140,800 [CI: 95,500-200,600] and the Democratic Republic of the Congo (2010: 39,700 [CI: 32,600-48,800]; 2050: 44,700 [CI: 27,100-70,500] will remain the countries most in need of policies for the prevention and management of SCA. We predict a decrease in the annual number of newborns with SCA in India (2010: 44,400 [CI: 33,700-59,100]; 2050: 33,900 [CI: 15,900-64,700]. The implementation of basic health interventions (e.g., prenatal diagnosis, penicillin prophylaxis, and vaccination for SCA in 2015, leading to significant reductions in excess mortality among under-five children with SCA, could, by 2050, prolong the lives of 5,302,900 [CI: 3

  2. Global burden of sickle cell anaemia in children under five, 2010-2050: modelling based on demographics, excess mortality, and interventions.

    Science.gov (United States)

    Piel, Frédéric B; Hay, Simon I; Gupta, Sunetra; Weatherall, David J; Williams, Thomas N

    2013-01-01

    The global burden of sickle cell anaemia (SCA) is set to rise as a consequence of improved survival in high-prevalence low- and middle-income countries and population migration to higher-income countries. The host of quantitative evidence documenting these changes has not been assembled at the global level. The purpose of this study is to estimate trends in the future number of newborns with SCA and the number of lives that could be saved in under-five children with SCA by the implementation of different levels of health interventions. First, we calculated projected numbers of newborns with SCA for each 5-y interval between 2010 and 2050 by combining estimates of national SCA frequencies with projected demographic data. We then accounted for under-five mortality (U5m) projections and tested different levels of excess mortality for children with SCA, reflecting the benefits of implementing specific health interventions for under-five patients in 2015, to assess the number of lives that could be saved with appropriate health care services. The estimated number of newborns with SCA globally will increase from 305,800 (confidence interval [CI]: 238,400-398,800) in 2010 to 404,200 (CI: 242,500-657,600) in 2050. It is likely that Nigeria (2010: 91,000 newborns with SCA [CI: 77,900-106,100]; 2050: 140,800 [CI: 95,500-200,600]) and the Democratic Republic of the Congo (2010: 39,700 [CI: 32,600-48,800]; 2050: 44,700 [CI: 27,100-70,500]) will remain the countries most in need of policies for the prevention and management of SCA. We predict a decrease in the annual number of newborns with SCA in India (2010: 44,400 [CI: 33,700-59,100]; 2050: 33,900 [CI: 15,900-64,700]). The implementation of basic health interventions (e.g., prenatal diagnosis, penicillin prophylaxis, and vaccination) for SCA in 2015, leading to significant reductions in excess mortality among under-five children with SCA, could, by 2050, prolong the lives of 5,302,900 [CI: 3,174,800-6,699,100] newborns with

  3. Theory Creation, Modification, and Testing: An Information-Processing Model and Theory of the Anticipated and Unanticipated Consequences of Research and Development

    Science.gov (United States)

    Perla, Rocco J.; Carifio, James

    2011-01-01

    Background: Extending Merton's (1936) work on the consequences of purposive social action, the model, theory and taxonomy outlined here incorporates and formalizes both anticipated and unanticipated research findings in a unified theoretical framework. The model of anticipated research findings was developed initially by Carifio (1975, 1977) and…

  4. Application of the accident consequences model of the German risk study to assessments of accident risks in different types of nuclear power plants

    International Nuclear Information System (INIS)

    Ehrhardt, J.; Bayer, A.

    1982-01-01

    Within the scope of the 'German Risk Study for Nuclear Power Plants' (Phase A) the accident consequence model UFOMOD was developed in the Karlsruhe Nuclear Research Center. This model originally developed for pressurized water reactors has now been extended in order to obtain results about accidental releases of activity from fast breeder and high-temperature reactors, too. (RW) [de

  5. The confounding effect of population structure on bayesian skyline plot inferences of demographic history

    DEFF Research Database (Denmark)

    Heller, Rasmus; Chikhi, Lounes; Siegismund, Hans

    2013-01-01

    Many coalescent-based methods aiming to infer the demographic history of populations assume a single, isolated and panmictic population (i.e. a Wright-Fisher model). While this assumption may be reasonable under many conditions, several recent studies have shown that the results can be misleading...... when it is violated. Among the most widely applied demographic inference methods are Bayesian skyline plots (BSPs), which are used across a range of biological fields. Violations of the panmixia assumption are to be expected in many biological systems, but the consequences for skyline plot inferences...... the best scheme for inferring demographic change over a typical time scale. Analyses of data from a structured African buffalo population demonstrate how BSP results can be strengthened by simulations. We recommend that sample selection should be carefully considered in relation to population structure...

  6. EJSCREEN Version 1, Demographic Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — This map service displays demographic data used in EJSCREEN. All demographic data were derived from American Community Survey 2006-2010 estimates. EJSCREEN is an...

  7. Demographic Risks of the Pension Reform in the Russian Federation

    Directory of Open Access Journals (Sweden)

    Arkady Konstantinovich Solovyev

    2016-03-01

    Full Text Available The purpose of the study is to analyze the impact of the demographic crisis in the country’s fiscal system. In the article, the pension system for the first time is considered as a multifactorial model, which during the different historical periods corrects the degree of its dependence on the interdependent complex of macroeconomic and demographic factors. The economically sound and socially correct accounting of the interference of retirement age and the specified development factors of pension system requires a fundamental change in the methodological approaches to the problem of raising the retirement age by using the actuarial methods of forecasting. The actuarial analysis of the problem of retirement age shows that the perception of the linear dependence on demographic parameters of the age when the national pension is awarded cannot be considered as a tool for regulating the efficiency of the pension system. For the science-based solution to the problem of rising the retirement age, along with the dynamics of demographic parameters, it is necessary to take into account the whole range of macroeconomic conditions for the state development as well as the long-term socio-economic consequences. Another significant result of the study are the specific parameters of the actuarial assessments of the impact of demographic and macroeconomic conditions of increasing the retirement age in Russia, conducted using the state statistical data. The practical proposals to mitigate the negative economic consequences are formulated. The key conclusion reached is that the raising of the retirement age should be aimed exclusively at the economic stimulation of the formation of the pension rights of the insured in the long term, rather than to the short-term savings of the state budget. The methodological approaches grounded in the work, and the quantitative results of the actuarial calculations may be applied in the shaping the public pension policy when

  8. The consequences of "Culture's consequences"

    DEFF Research Database (Denmark)

    Knudsen, Fabienne; Froholdt, Lisa Loloma

    2009-01-01

      In this article, it is claimed that research on cross-cultural crews is dominated by one specific understanding of the concept of culture, which is static, evenly distributed and context-independent. Such a conception of culture may bring some basic order while facing an unknown culture...... review of the theory of Geert Hofstede, the most renowned representative of this theoretical approach. The practical consequences of using such a concept of culture is then analysed by means of a critical review of an article applying Hofstede to cross-cultural crews in seafaring. Finally, alternative...... views on culture are presented. The aim of the article is, rather than to promote any specific theory, to reflect about diverse perspectives of cultural sense-making in cross-cultural encounters. Udgivelsesdato: Oktober...

  9. Demographic Differences in Organizational Commitment to the University of College of Business Administration Students: An Application of the Allen and Meyer Model

    Science.gov (United States)

    Love, Kevin G.

    2013-01-01

    Organizational commitment of undergraduate college students to the university was measured by modifying an established measure and demographic differences were examined. Affective, continuance, and normative commitment facets were assessed. No differences based upon gender, race, and GPA were found. Length of time at the university and transfer…

  10. Population-level consequences of spatially heterogeneous exposure to heavy metals in soil: An individual-based model of springtails

    DEFF Research Database (Denmark)

    Meli, Mattia; Auclerc, Apolline; Palmqvist, Annemette

    2013-01-01

    Contamination of soil with toxic heavy metals poses a major threat to the environment and human health. Anthropogenic sources include smelting of ores, municipal wastes, fertilizers, and pesticides. In assessing soil quality and the environmental and ecological risk of contamination with heavy...... metals, often homogeneous contamination of the soil is assumed. However, soils are very heterogeneous environments. Consequently, both contamination and the response of soil organisms can be assumed to be heterogeneous. This might have consequences for the exposure of soil organisms...

  11. Experimental modelling of the consequences of brief late gestation asphyxia on newborn lamb behaviour and brain structure.

    Directory of Open Access Journals (Sweden)

    Margie Castillo-Melendez

    Full Text Available Brief but severe asphyxia in late gestation or at the time of birth may lead to neonatal hypoxic ischemic encephalopathy and is associated with long-term neurodevelopmental impairment. We undertook this study to examine the consequences of transient in utero asphyxia in late gestation fetal sheep, on the newborn lamb after birth. Surgery was undertaken at 125 days gestation for implantation of fetal catheters and placement of a silastic cuff around the umbilical cord. At 132 days gestation (0.89 term, the cuff was inflated to induce umbilical cord occlusion (UCO, or sham (control. Fetal arterial blood samples were collected for assessment of fetal wellbeing and the pregnancy continued until birth. At birth, behavioral milestones for newborn lambs were recorded over 24 h, after which the lambs were euthanased for brain collection and histopathology assessments. After birth, UCO lambs displayed significant latencies to (i use all four legs, (ii attain a standing position, (iii find the udder, and (iv successfully suckle--compared to control lambs. Brains of UCO lambs showed widespread pathologies including cell death, white matter disruption, intra-parenchymal hemorrhage and inflammation, which were not observed in full term control brains. UCO resulted in some preterm births, but comparison with age-matched preterm non-UCO control lambs showed that prematurity per se was not responsible for the behavioral delays and brain structural abnormalities resulting from the in utero asphyxia. These results demonstrate that a single, brief fetal asphyxic episode in late gestation results in significant grey and white matter disruption in the developing brain, and causes significant behavioral delay in newborn lambs. These data are consistent with clinical observations that antenatal asphyxia is causal in the development of neonatal encephalopathy and provide an experimental model to advance our understanding of neuroprotective therapies.

  12. The consequences of chromosomal aneuploidy on gene expression profiles in a cell line model for prostate carcinogenesis.

    Science.gov (United States)

    Phillips, J L; Hayward, S W; Wang, Y; Vasselli, J; Pavlovich, C; Padilla-Nash, H; Pezullo, J R; Ghadimi, B M; Grossfeld, G D; Rivera, A; Linehan, W M; Cunha, G R; Ried, T

    2001-11-15

    Here we report the genetic characterization of immortalized prostate epithelial cells before and after conversion to tumorigenicity using molecular cytogenetics and microarray technology. We were particularly interested to analyze the consequences of acquired chromosomal aneuploidies with respect to modifications of gene expression profiles. Compared with nontumorigenic but immortalized prostate epithelium, prostate tumor cell lines showed high levels of chromosomal rearrangements that led to gains of 1p, 5, 11q, 12p, 16q, and 20q and losses of 1pter, 11p, 17, 20p, 21, 22, and Y. Of 5700 unique targets on a 6.5K cDNA microarray, approximately 3% were subject to modification in expression levels; these included GRO-1, -2, IAP-1,- 2, MMP-9, and cyclin D1, which showed increased expression, and TRAIL, BRCA1, and CTNNA, which showed decreased expression. Thirty % of expression changes occurred in regions the genomic copy number of which remained balanced. Of the remainder, 42% of down-regulated and 51% of up-regulated genes mapped to regions present in decreased or increased genomic copy numbers, respectively. A relative gain or loss of a chromosome or chromosomal arm usually resulted in a statistically significant increase or decrease, respectively, in the average expression level of all of the genes on the chromosome. However, of these genes, very few (e.g., 5 of 101 genes on chromosome 11q), and in some instances only two genes (MMP-9 and PROCR on chromosome 20q), were overexpressed by > or =1.7-fold when scored individually. Cluster analysis by gene function suggests that prostate tumorigenesis in these cell line models involves alterations in gene expression that may favor invasion, prevent apoptosis, and promote growth.

  13. Abortion — facts and consequences

    OpenAIRE

    Perinčić, Robert

    1990-01-01

    The author sets forth some of the most recent demographic data, important directions of legal documents as regards abortion, tackling medical and ethical problems of abortion. Some essentials particulars are also given as to the embryonic and foetal development. The whole paper concerns the problems of legal abortion during the first three months of pregnancy. The second part of the paper relates to the consequences of abortion affecting the physical and mental health of a woman as show...

  14. and consequences

    Directory of Open Access Journals (Sweden)

    P. Athanasopoulou

    2011-01-01

    Full Text Available (a Purpose: The purpose of this research is to identify the types of CSR initiatives employed by sports organisations; their antecedents, and their consequences for the company and society. (b Design/methodology/approach: This study is exploratory in nature. Two detailed case studies were conducted involving the football team and the basketball team of one professional, premier league club in Greece and their CSR initiatives. Both teams have the same name, they belong to one of the most popular teams in Greece with a large fan population; have both competed in International Competitions (UEFA’s Champion League; Final Four of the European Tournament and have realised many CSR initiatives in the past. The case studies involved in depth, personal interviews of managers responsible for CSR in each team. Case study data was triangulated with documentation and search of published material concerning CSR actions. Data was analysed with content analysis. (c Findings: Both teams investigated have undertaken various CSR activities the last 5 years, the football team significantly more than the basketball team. Major factors that affect CSR activity include pressure from leagues; sponsors; local community, and global organisations; orientation towards fulfilling their duty to society, and team CSR strategy. Major benefits from CSR include relief of vulnerable groups and philanthropy as well as a better reputation for the firm; increase in fan base; and finding sponsors more easily due to the social profile of the team. However, those benefits are not measured in any way although both teams observe increase in tickets sold; web site traffic and TV viewing statistics after CSR activities. Finally, promotion of CSR is mainly done through web sites; press releases; newspapers, and word-of-mouth communications. (d Research limitations/implications: This study involves only two case studies and has limited generalisability. Future research can extend the

  15. Renal Aging: Causes and Consequences.

    Science.gov (United States)

    O'Sullivan, Eoin D; Hughes, Jeremy; Ferenbach, David A

    2017-02-01

    Individuals age >65 years old are the fastest expanding population demographic throughout the developed world. Consequently, more aged patients than before are receiving diagnoses of impaired renal function and nephrosclerosis-age-associated histologic changes in the kidneys. Recent studies have shown that the aged kidney undergoes a range of structural changes and has altered transcriptomic, hemodynamic, and physiologic behavior at rest and in response to renal insults. These changes impair the ability of the kidney to withstand and recover from injury, contributing to the high susceptibility of the aged population to AKI and their increased propensity to develop subsequent progressive CKD. In this review, we examine these features of the aged kidney and explore the various validated and putative pathways contributing to the changes observed with aging in both experimental animal models and humans. We also discuss the potential for additional study to increase understanding of the aged kidney and lead to novel therapeutic strategies. Copyright © 2017 by the American Society of Nephrology.

  16. Comparative study of an HIV risk scorecard and regression models to rank effects of demographic characteristics on risk of aquiring an HIV infection

    OpenAIRE

    Wilbert Sibanda; Philip Pretorius

    2013-01-01

    This research paper covers the development of an HIV risk scorecard using SAS Enterprise MinerTM. The HIV risk scorecard was developed using the 2007 South African annual antenatal HIV and syphilis seroprevalence data. Limited comparisons are made with a more recent 2010 antenatal database. Antenatal data contains various demographic characteristics for each pregnant woman, such as pregnant woman’s age, male sexual partner’s age, population group, level of education, gravidity, parity, HIV an...

  17. Reactor safety study. An assessment of accident risks in U. S. commercial nuclear power plants. Appendix VI. Calculation of reactor accident consequences. [PWR and BWR

    Energy Technology Data Exchange (ETDEWEB)

    1975-10-01

    Information is presented concerning the radioactive releases from the containment following accidents; radioactive inventory of the reactor core; atmospheric dispersion; reactor sites and meteorological data; radioactive decay and deposition from plumes; finite distance of plume travel; dosimetric models; health effects; demographic data; mitigation of radiation exposure; economic model; and calculated results with consequence model.

  18. Reactor safety study. An assessment of accident risks in U.S. commercial nuclear power plants. Appendix VI. Calculation of reactor accident consequences

    International Nuclear Information System (INIS)

    1975-10-01

    Information is presented concerning the radioactive releases from the containment following accidents; radioactive inventory of the reactor core; atmospheric dispersion; reactor sites and meteorological data; radioactive decay and deposition from plumes; finite distance of plume travel; dosimetric models; health effects; demographic data; mitigation of radiation exposure; economic model; and calculated results with consequence model

  19. The 7-factor hybrid model of DSM-5 PTSD symptoms and alcohol consumption and consequences in a national sample of trauma-exposed veterans.

    Science.gov (United States)

    Claycomb Erwin, Meredith; Charak, Ruby; Durham, Tory A; Armour, Cherie; Lv, Xin; Southwick, Steven M; Elhai, Jon D; Pietrzak, Robert H

    2017-10-01

    The purpose of the present study was to investigate associations between the 7-factor hybrid model of DSM-5 posttraumatic stress disorder (PTSD) symptoms, which includes intrusions, avoidance, negative affect, anhedonia, externalizing behaviors, anxious arousal, and dysphoric arousal symptoms, and alcohol consumption and consequences. A nationally representative sample of 916 trauma-exposed U.S. military veterans were administered the Trauma History Screen, PTSD Checklist-5, and Alcohol Use Disorders Identification Test. Confirmatory factor analyses were conducted to determine associations between the 7-factor hybrid model of PTSD symptoms, and alcohol consumption and consequences. Results revealed that lifetime dysphoric arousal (r=0.31), negative affect (r=0.30), and anhedonia (r=0.29) symptom clusters were most strongly associated with past-year alcohol consequences. No significant associations were observed for alcohol consumption. While the cross-sectional study design does not allow one to ascertain causative associations between PTSD factors and alcohol consumption and consequences, results generally align with the self-medication hypothesis, as PTSD factors reflecting internalizing were most strongly related to alcohol-related consequences. These results underscore the importance of assessing for alcohol use problems in veterans who score highly on PTSD symptoms reflecting internalizing symptomatology. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Modelling the consequences of crop-wild relative gene flow: A sensitivity analysis of the effects of outcrossing rates and hybrid vigour breakdown in Lactuca

    NARCIS (Netherlands)

    Hooftman, D.A.P.; Oostermeijer, J.G.B.; Marquard, E.; den Nijs, J.C.M.

    2008-01-01

    1. Hybridization between crops and their wild relatives may enhance invasiveness and change their niche dynamics. This is regarded as a major biosafety problem in terms of the development of noxious, invasive weeds and the loss of the genetic identity of native species. Modelling the consequences of

  1. Hepatic steatosis : metabolic consequences

    NARCIS (Netherlands)

    Boer, Adriana Maria den

    2006-01-01

    In this thesis we focused on the causes and consequences of hepatic steatosis. Epidemiological studies in humans, as well as experimental studies in animal models, have shown an association between visceral obesity and dyslipidemia, insulin resistance and type 2 diabetes mellitus. The mechanism

  2. Reanalysis of the consequences of a beyond-design based brine intrusion in the Schachtanlage Asse II. Further development of the radio-ecological modeling

    International Nuclear Information System (INIS)

    Kueppers, Christian; Ustohalova, Veronika; Steinhoff, Mathias

    2011-01-01

    The reanalysis of the consequences of a beyond-design based brine intrusion in the Schachtanlage Asse includes the following chapters: (1) Scope and introduction. (2) Overview on the methodology. (3) Modeling of the transport in the overlying rock and radiation exposure: Modeling of the radionuclide migration in the overlying rock considering the solubility limits and different retention and retarding effects; description of the used model for the radiation exposure calculations, quality assurance of the model and the calculations. (4) Results and reanalysis for the scenario I (GRS scenario). (5) Radiation exposure considering the solubility limits and transport calculations (scenario II). (6) Possibilities of monitoring in the Asse environment. (7) Estimation of collective doses as a consequence of contaminated water release into the biosphere and use as drinking water. (8) Discussion of the radiation exposure calculations in the former study of GRS (2009).

  3. Use of HGSYSTEM/UF6 and MACCS2 for the Building 9204-2E safety analysis report consequence analysis: General overview and comparison of models

    International Nuclear Information System (INIS)

    Lombardi, D.A.; Brock, W.R.

    1998-01-01

    Building 9204-2E is used for assembly, disassembly, and storage of weapons components, and quality operations. The building, built in 1971, is a three story structure approximately 101 m long, 51 m wide, and 21 m high located in the western exclusion area of the Y-12 Plant, Oak Ridge, Tennessee. For these activities, several types of hazardous and radioactive materials are used and stored in Building 9204-2E. During a fire, criticality event, or other accident, the potential exists for the release of uranium and other hazardous materials from the building to the atmosphere. A Safety Analysis Report (SAR) is being prepared for Building 9204-2E, in which the consequences of such releases to on-site workers and the off-site public are being analyzed. Consequence estimates from accidental airborne releases are generally calculated using computer models that simulate dispersion and transport of the plume as it travels downwind. For the Building 9204-2E SAR, two candidate atmospheric dispersion candidate models have bene identified for use: (1) the Heavy Gas System-Uranium Hexafluoride (HGSYSTEM/UF 6 ) Model Suite, and (2) the MELCOR Accident Consequence Code System-2 (MACCS2). The purpose of this paper is to provide a general description of the two model suites and compared model results for generic release cases, representative of those that will be analyzed in the Building 9204-2E SAR. Recommendations for use of the model suites in the SAR are also discussed

  4. Phenomenological consequences of supersymmetry

    International Nuclear Information System (INIS)

    Hinchliffe, I.; Littenberg, L.

    1982-01-01

    This paper deals with the phenomenological consequences of supersymmetric theories, and with the implications of such theories for future high energy machines. The paper represents the work of a subgroup at the meeting. The authors are concerned only with high energy predictions of supersymmetry; low energy consequences (for example in the K/sub o/K-bar/sub o/ system) are discussed in the context of future experiments by another group, and will be mentioned briefly only in the context of constraining existing models. However a brief section is included on the implication for proton decay, although detailed experimental questions are not discussed

  5. Risk-oriented analysis of the German prototype fast breeder reactor SNR-300: off-site accident consequence model and results of the study

    International Nuclear Information System (INIS)

    Bayer, A.; Ehrhardt, J.

    1984-01-01

    Accident off-site consequence calculations and risk assessments performed for the ''risk oriented analysis'' of the German prototype fast breeder reactor SNR-300 were performed with a modified version of the off-site accident consequence model UFOMOD. The modifications mainly relate to the deposition and resuspension processes, the ingestion model, and the dose factors. Consequence calculations at the site of Kalkar on the Rhine River were performed for 115 weather sequences in 36 wind directions. They were based on seven release categories evaluated for the SNR-300 with two different fueling strategies: plutonium from Magnox reactors only and plutonium from light water reactors and Magnox reactors. In parallel, the corresponding frequencies of occurrence are determined. The following results are generated: 1. complementary cumulative frequency distribution functions for collective fatalities and collective doses 2. expected values of the collective fatalities and collective doses as well as distance-dependent expected values of individual fatality 3. contributions of the different exposure pathways to fatalities with respect to the various organs. For comparison with the risk of a PWR-1300, calculations for the PWR-1300 of the ''German Risk Study'' were repeated with the same modified consequence model. Comparison shows that smaller risks result for the SNR-300. However, the confidence interval bandwidths obtained for the frequencies of the release categories for the SNR-300 are larger than those of the PWR-1300

  6. Consequences of team charter quality: Teamwork mental model similarity and team viability in engineering design student teams

    Science.gov (United States)

    Conway Hughston, Veronica

    Since 1996 ABET has mandated that undergraduate engineering degree granting institutions focus on learning outcomes such as professional skills (i.e. solving unstructured problems and working in teams). As a result, engineering curricula were restructured to include team based learning---including team charters. Team charters were diffused into engineering education as one of many instructional activities to meet the ABET accreditation mandates. However, the implementation and execution of team charters into engineering team based classes has been inconsistent and accepted without empirical evidence of the consequences. The purpose of the current study was to investigate team effectiveness, operationalized as team viability, as an outcome of team charter implementation in an undergraduate engineering team based design course. Two research questions were the focus of the study: a) What is the relationship between team charter quality and viability in engineering student teams, and b) What is the relationship among team charter quality, teamwork mental model similarity, and viability in engineering student teams? Thirty-eight intact teams, 23 treatment and 15 comparison, participated in the investigation. Treatment teams attended a team charter lecture, and completed a team charter homework assignment. Each team charter was assessed and assigned a quality score. Comparison teams did not join the lecture, and were not asked to create a team charter. All teams completed each data collection phase: a) similarity rating pretest; b) similarity posttest; and c) team viability survey. Findings indicate that team viability was higher in teams that attended the lecture and completed the charter assignment. Teams with higher quality team charter scores reported higher levels of team viability than teams with lower quality charter scores. Lastly, no evidence was found to support teamwork mental model similarity as a partial mediator of the team charter quality on team viability

  7. Gender inequalities and demographic behavior.

    Science.gov (United States)

    1995-01-01

    A summary was provided of the central findings about gender inequalities in Egypt, India, Ghana, and Kenya published by the Population Council in 1994. These countries exhibited gender inequalities in different ways: the legal, economic, and educational systems; family planning and reproductive health services; and the health care system. All countries had in common a high incidence of widowhood. Widowhood was linked with high levels of insecurity, which were linked with high fertility. Children thus became insurance in old age. In Ghana, women's insecurity was threatened through high levels of marital instability and polygyny. In Egypt, insecurity was translated into economic vulnerability because of legal discrimination against women when family systems were disrupted. In India and all four countries, insecurity was reflective of limited access to education, an impediment to economic autonomy. In all four countries, women's status was inferior due to limited control over reproductive decision making about childbearing limits and contraception. In India, the cultural devaluation of girls contributed to higher fertility to satisfy the desire for sons. In India and Egypt, family planning programs were dominated by male-run organizations that were more concerned about demographic objectives than reproductive health. The universal inequality was the burden women carry for contraception. Family planning programs have ignored the local realities of reproductive behavior, family structures, and gender relations. The assumption that husbands and wives have similar fertility goals or that fathers fully share the costs of children is mistaken in countries such as Ghana. Consequently, fertility has declined less than 13% in Ghana, but fertility has declined by over 30% in Kenya. Family planning programs must be aware of gender issues.

  8. Accident consequence assessment code development

    International Nuclear Information System (INIS)

    Homma, T.; Togawa, O.

    1991-01-01

    This paper describes the new computer code system, OSCAAR developed for off-site consequence assessment of a potential nuclear accident. OSCAAR consists of several modules which have modeling capabilities in atmospheric transport, foodchain transport, dosimetry, emergency response and radiological health effects. The major modules of the consequence assessment code are described, highlighting the validation and verification of the models. (author)

  9. Improving public health training and research capacity in Africa: a replicable model for linking training to health and socio-demographic surveillance data

    Directory of Open Access Journals (Sweden)

    Jill R. Williams

    2010-08-01

    Full Text Available Background: Research training for public health professionals is key to the future of public health and policy in Africa. A growing number of schools of public health are connected to health and socio-demographic surveillance system field sites in developing countries, in Africa and Asia in particular. Linking training programs with these sites provides important opportunities to improve training, build local research capacity, foreground local health priorities, and increase the relevance of research to local health policy. Objective: To increase research training capacity in public health programs by providing targeted training to students and increasing the accessibility of existing data. Design: This report is a case study of an approach to linking public health research and training at the University of the Witwatersrand. We discuss the development of a sample training database from the Agincourt Health and Socio-demographic Surveillance System in South Africa and outline a concordant transnational intensive short course on longitudinal data analysis offered by the University of the Witwatersrand and the University of Colorado-Boulder. This case study highlights ways common barriers to linking research and training can be overcome. Results and Conclusions: This collaborative effort demonstrates that linking training to ongoing data collection can improve student research, accelerate student training, and connect students to an international network of scholars. Importantly, the approach can be adapted to other partnerships between schools of public health and longitudinal research sites.

  10. Global demographic change and climate policies

    NARCIS (Netherlands)

    Gerlagh, Reyer; Jaimes, Richard; Motavasseli, Ali

    2017-01-01

    Between 1950 and 2017, world average life expectancy increased from below-50 to above-70, while the fertility rate dropped from 5 to about 2.5. We develop and calibrate an analytic climate-economy model with overlapping generations to study the effect of such demographic change on capital markets

  11. Modelling hydrological changes in surface in relation with anthropogenic drivers and consequences on human health and local economic

    Science.gov (United States)

    Sandoz, Alain; Leblond, Agnès; Boutron, Olivier

    2016-04-01

    of the watershed. The modeling also performed to simulate a change in rainfall locally to measure hydrological and environmental consequences. According to these scenarios, it was possible to map the potential areas of mosquitoes breeding sites (presence / absence of mosquitoes) and their impact on urban populations in terms of health risks and nuisance. This territory represents many interests for decision-makers interested in issues of governance and renaturation. To improve the inclusion of better water governance and territories, as well as facilitate dynamic annealing, it might be necessary to help decision-makers having a better knowledge of the impact of human drivers on water management on the territory. This increased knowledge would also enable local decision-makers to improve their awareness of the heritage and biodiversity of wetlands. This project was funded by the French Ministry of Ecology, Sustainable Development and Energy as part of the projects Water and Territories.

  12. Demographics, political power and economic growth.

    Science.gov (United States)

    Holtz-eakin, D

    1993-01-01

    "Growth theory may be used to predict the response of saving, capital formation, and output growth to large demographic shifts. Such large shifts would also be expected to alter the demand for government services and the desired levels of taxation in the population. This paper extends the overlapping-generations model of economic growth to predict the evolution of government tax and spending policy through the course of a major demographic shift. Simulations suggest that this approach may yield valuable insights into the evolution of policy in the United States and other industrialized economies." excerpt

  13. Differential contribution of demographic rate synchrony to population synchrony in barn swallows.

    Science.gov (United States)

    Schaub, Michael; von Hirschheydt, Johann; Grüebler, Martin U

    2015-11-01

    Populations of many species show temporally synchronous dynamics over some range, mostly caused by spatial autocorrelation of the environment that affects demographic rates. Synchronous fluctuation of a demographic rate is a necessary, but not sufficient condition for population synchrony because population growth is differentially sensitive to variation in demographic rates. Little is known about the relative effects of demographic rates to population synchrony, because it is rare that all demographic rates from several populations are known. We develop a hierarchical integrated population model with which all relevant demographic rates from all study populations can be estimated and apply it to demographic data of barn swallows Hirundo rustica from nine sites that were between 19 and 224 km apart from each other. We decompose the variation of the population growth and of the demographic rates (apparent survival, components of productivity, immigration) into global and local temporal components using random effects which allowed the estimation of synchrony of these rates. The barn swallow populations fluctuated synchronously, but less so than most demographic rates. The highest synchrony showed the probability of double brooding, while fledging success was highly asynchronous. Apparent survival, immigration and total productivity achieved intermediate levels of synchrony. The growth of all populations was most sensitive to changes in immigration and adult apparent survival, and both of them contributed to the observed temporal variation of population growth rates. Using a simulation model, we show that immigration and apparent survival of juveniles and adults were able to induce population synchrony, but not components of local productivity due to their low population growth rate sensitivity. Immigrants are mostly first-time breeders, and consequently, their number depends on the productivity of neighbouring populations. Since total productivity was synchronized

  14. A Community Patient Demographic System

    OpenAIRE

    Gabler, James M.; Simborg, Donald W.

    1985-01-01

    A Community Patient Demographic System is described. Its purpose is to link patient identification, demographic and insurance information among multiple organizations in a community or among multiple registration systems within the same organization. This function requires that there be a competent patient identification methodology and clear definition of local responsibilities for number assignment and database editing.

  15. Demographic Trends: Impact on Schools

    Science.gov (United States)

    Chong, Sylvia N. Y.; Cheah, Horn Mun

    2010-01-01

    Background: Singapore is experiencing great demographic change. These demographic trends show fewer young people and declining birth rates, greater longevity for ageing generations and an increase in the number of non-Singaporean residents. Statistics also show that more than half of the total population increase in the last decades was…

  16. Epidemiological and demographic HIV/AIDS projections: South Africa

    African Journals Online (AJOL)

    Epidemiological and demographic HIV/AIDS projections: South Africa. ... African Journal of AIDS Research ... Projections and the Spectrum model program developed by the Futures Group were used to model the South African HIV epidemic, project future trends in HIV/AIDS and estimate the demographic impact of AIDS.

  17. Health effects models for nuclear power plant accident consequence analysis. Modification of models resulting from addition of effects of exposure to alpha-emitting radionuclides: Revision 1, Part 2, Scientific bases for health effects models, Addendum 2

    Energy Technology Data Exchange (ETDEWEB)

    Abrahamson, S. [Wisconsin Univ., Madison, WI (United States); Bender, M.A. [Brookhaven National Lab., Upton, NY (United States); Boecker, B.B.; Scott, B.R. [Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (United States). Inhalation Toxicology Research Inst.; Gilbert, E.S. [Pacific Northwest Lab., Richland, WA (United States)

    1993-05-01

    The Nuclear Regulatory Commission (NRC) has sponsored several studies to identify and quantify, through the use of models, the potential health effects of accidental releases of radionuclides from nuclear power plants. The Reactor Safety Study provided the basis for most of the earlier estimates related to these health effects. Subsequent efforts by NRC-supported groups resulted in improved health effects models that were published in the report entitled {open_quotes}Health Effects Models for Nuclear Power Plant Consequence Analysis{close_quotes}, NUREG/CR-4214, 1985 and revised further in the 1989 report NUREG/CR-4214, Rev. 1, Part 2. The health effects models presented in the 1989 NUREG/CR-4214 report were developed for exposure to low-linear energy transfer (LET) (beta and gamma) radiation based on the best scientific information available at that time. Since the 1989 report was published, two addenda to that report have been prepared to (1) incorporate other scientific information related to low-LET health effects models and (2) extend the models to consider the possible health consequences of the addition of alpha-emitting radionuclides to the exposure source term. The first addendum report, entitled {open_quotes}Health Effects Models for Nuclear Power Plant Accident Consequence Analysis, Modifications of Models Resulting from Recent Reports on Health Effects of Ionizing Radiation, Low LET Radiation, Part 2: Scientific Bases for Health Effects Models,{close_quotes} was published in 1991 as NUREG/CR-4214, Rev. 1, Part 2, Addendum 1. This second addendum addresses the possibility that some fraction of the accident source term from an operating nuclear power plant comprises alpha-emitting radionuclides. Consideration of chronic high-LET exposure from alpha radiation as well as acute and chronic exposure to low-LET beta and gamma radiations is a reasonable extension of the health effects model.

  18. Implications of research staff demographics for psychological science.

    Science.gov (United States)

    Does, Serena; Ellemers, Naomi; Dovidio, John F; Norman, Jasmine B; Mentovich, Avital; van der Lee, Romy; Goff, Phillip Atiba

    2018-03-01

    Long-standing research traditions in psychology have established the fundamental impact of social categories, such as race and gender, on people's perceptions of themselves and others, as well as on the general human cognition and behavior. However, there is a general tendency to ignore research staff demographics (e.g., researchers' race and gender) in research development and research reports. Variation in research staff demographics can exert systematic and scientifically informative influences on results from psychological research. Consequently, research staff demographics need to be considered, studied, and/or reported, along with how these demographics were allowed to vary across participants or conditions (e.g., random assignment, matched with participant demographics, or included as a factor in the experimental design). In addition to providing an overview of multidisciplinary evidence of research staff demographics effects, we discuss how research staff demographics might influence research findings through (a) ingroup versus outgroup effects, (b) stereotype and (implicit) bias effects, and (c) priming and social tuning effects. Finally, an overview of recommended considerations is included (see the Appendix) to help illustrate how to systematically incorporate relevant research staff demographics in psychological science. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  19. [The demographic potential of Russia].

    Science.gov (United States)

    Vishnevskii, A

    1998-05-01

    This is a general review of current demographic trends in Russia. The author analyzes the decline in population size that is taking place at the end of the twentieth century, and traces its origins as far back as the disturbances associated with World War I, the Communist revolution, and the civil war that followed it. Political repression during the Stalinist period and the tribulations experienced during World War II also contributed to the current demographic crisis. The author discusses the changes in migration patterns and the declining fertility and increasing mortality rates. The decline in life expectancy is also addressed. Some comparisons are made with the demographic situation in other European countries.

  20. Phenomenological consequences of supersymmetry

    International Nuclear Information System (INIS)

    Hinchliffe, I.; Littenberg, L.

    1982-01-01

    This report deals with the phenomenological consequences of supersymmetric theories, and with the implications of such theories for future high energy machines. It is concerned only with high energy predictions of supersymmetry; low energy consequences (for example in the K/sub o/anti K/sub o/ system) are discussed in the context of future experiments by another group, and will be mentioned briefly only in the context of constraining existing models. However a brief section is included on the implication for proton decay, although detailed experimental questions are not discussed. The report is organized as follows. Section I consists of a brief review of supersymmetry and the salient features of existing supersymmetric models; this section can be ignored by those familiar with such models since it contains nothing new. Section 2 deals with the consequences for nucleon decay of SUSY. The remaining sections then discuss the physics possibilities of various machines; e anti e in Section 3, ep in Section 4, pp (or anti pp) colliders in Section 5 and fixed target hadron machines in Section 6

  1. Practical Application of the MFM Suite on a PWR System: Modelling and Reasoning on Causes and Consequences of Process Anomalies

    DEFF Research Database (Denmark)

    Zhang, Xinxin; Thunem, Harald P - J; Lind, Morten

    2014-01-01

    and linking the MFM model to its process components. The purpose of this report is to make a comprehensive demonstration of how to use the MFM Suite to develop MFM models and run causal reasoning for abnormal situations. This report will explain the capability of representing process and operational knowledge...... by using the MFM methodolog y, and demonstrate how the model combined with the MFM reasoning can be used to evaluate the plant state, identify the current situation and support operational decisions. The report will provide a detailed explanation of MFM concepts by modelling the prim ary side system...... systems. Two of the modelling examples can be found in HWR - 990 and HWR - 1059. The inherent causal reasoning capability enabled the developed MFM models to be used for diagnostic and prognostic analysis. These MFM models h ave been used to develop the basis for implementing operator support tools...

  2. Inhibition of galectin-3 ameliorates the consequences of cardiac lipotoxicity in a rat model of diet-induced obesity

    Directory of Open Access Journals (Sweden)

    Gema Marín-Royo

    2018-02-01

    Full Text Available Obesity is accompanied by metabolic alterations characterized by insulin resistance and cardiac lipotoxicity. Galectin-3 (Gal-3 induces cardiac inflammation and fibrosis in the context of obesity; however, its role in the metabolic consequences of obesity is not totally established. We have investigated the potential role of Gal-3 in the cardiac metabolic disturbances associated with obesity. In addition, we have explored whether this participation is, at least partially, acting on mitochondrial damage. Gal-3 inhibition in rats that were fed a high-fat diet (HFD for 6 weeks with modified citrus pectin (MCP; 100 mg/kg/day attenuated the increase in cardiac levels of total triglyceride (TG. MCP treatment also prevented the increase in cardiac protein levels of carnitine palmitoyl transferase IA, mitofusin 1, and mitochondrial complexes I and II, reactive oxygen species accumulation and decrease in those of complex V but did not affect the reduction in 18F-fluorodeoxyglucose uptake observed in HFD rats. The exposure of cardiac myoblasts (H9c2 to palmitic acid increased the rate of respiration, mainly due to an increase in the proton leak, glycolysis, oxidative stress, β-oxidation and reduced mitochondrial membrane potential. Inhibition of Gal-3 activity was unable to affect these changes. Our findings indicate that Gal-3 inhibition attenuates some of the consequences of cardiac lipotoxicity induced by a HFD since it reduced TG and lysophosphatidyl choline (LPC levels. These reductions were accompanied by amelioration of the mitochondrial damage observed in HFD rats, although no improvement was observed regarding insulin resistance. These findings increase the interest for Gal-3 as a potential new target for therapeutic intervention to prevent obesity-associated cardiac lipotoxicity and subsequent mitochondrial dysfunction.

  3. Complexity and demographic explanations of cumulative culture.

    Science.gov (United States)

    Querbes, Adrien; Vaesen, Krist; Houkes, Wybo

    2014-01-01

    Formal models have linked prehistoric and historical instances of technological change (e.g., the Upper Paleolithic transition, cultural loss in Holocene Tasmania, scientific progress since the late nineteenth century) to demographic change. According to these models, cumulation of technological complexity is inhibited by decreasing--while favoured by increasing--population levels. Here we show that these findings are contingent on how complexity is defined: demography plays a much more limited role in sustaining cumulative culture in case formal models deploy Herbert Simon's definition of complexity rather than the particular definitions of complexity hitherto assumed. Given that currently available empirical evidence doesn't afford discriminating proper from improper definitions of complexity, our robustness analyses put into question the force of recent demographic explanations of particular episodes of cultural change.

  4. Complexity and demographic explanations of cumulative culture.

    Directory of Open Access Journals (Sweden)

    Adrien Querbes

    Full Text Available Formal models have linked prehistoric and historical instances of technological change (e.g., the Upper Paleolithic transition, cultural loss in Holocene Tasmania, scientific progress since the late nineteenth century to demographic change. According to these models, cumulation of technological complexity is inhibited by decreasing--while favoured by increasing--population levels. Here we show that these findings are contingent on how complexity is defined: demography plays a much more limited role in sustaining cumulative culture in case formal models deploy Herbert Simon's definition of complexity rather than the particular definitions of complexity hitherto assumed. Given that currently available empirical evidence doesn't afford discriminating proper from improper definitions of complexity, our robustness analyses put into question the force of recent demographic explanations of particular episodes of cultural change.

  5. EJSCREEN Demographic Indicators 2015 Public

    Data.gov (United States)

    U.S. Environmental Protection Agency — EJSCREEN uses demographic factors as very general indicators of a community's potential susceptibility to the types of environmental factors included in this...

  6. EJSCREEN Demographic Indicators 2016 Public

    Data.gov (United States)

    U.S. Environmental Protection Agency — EJSCREEN uses demographic factors as very general indicators of a community's potential susceptibility to the types of environmental factors included in this...

  7. The Russian Market of University Services: Social and Demographic Aspects

    Science.gov (United States)

    Bydanova, Elizaveta; Mushketova, Natalia; Rouet, Gilles

    2015-01-01

    Purpose: The purpose of this paper is to analyze the impact of demographic, social, economic and international aspects on the market of university services in Russia. It also reminds readers briefly of the evolution of the Russian higher education system during the last 20 years and considers some consequences of the current public policy and…

  8. Cross-site comparison of land-use decision-making and its consequences across land systems with a generalized agent-based model.

    Science.gov (United States)

    Magliocca, Nicholas R; Brown, Daniel G; Ellis, Erle C

    2014-01-01

    Local changes in land use result from the decisions and actions of land-users within land systems, which are structured by local and global environmental, economic, political, and cultural contexts. Such cross-scale causation presents a major challenge for developing a general understanding of how local decision-making shapes land-use changes at the global scale. This paper implements a generalized agent-based model (ABM) as a virtual laboratory to explore how global and local processes influence the land-use and livelihood decisions of local land-users, operationalized as settlement-level agents, across the landscapes of six real-world test sites. Test sites were chosen in USA, Laos, and China to capture globally-significant variation in population density, market influence, and environmental conditions, with land systems ranging from swidden to commercial agriculture. Publicly available global data were integrated into the ABM to model cross-scale effects of economic globalization on local land-use decisions. A suite of statistics was developed to assess the accuracy of model-predicted land-use outcomes relative to observed and random (i.e. null model) landscapes. At four of six sites, where environmental and demographic forces were important constraints on land-use choices, modeled land-use outcomes were more similar to those observed across sites than the null model. At the two sites in which market forces significantly influenced land-use and livelihood decisions, the model was a poorer predictor of land-use outcomes than the null model. Model successes and failures in simulating real-world land-use patterns enabled the testing of hypotheses on land-use decision-making and yielded insights on the importance of missing mechanisms. The virtual laboratory approach provides a practical framework for systematic improvement of both theory and predictive skill in land change science based on a continual process of experimentation and model enhancement.

  9. Cross-site comparison of land-use decision-making and its consequences across land systems with a generalized agent-based model.

    Directory of Open Access Journals (Sweden)

    Nicholas R Magliocca

    Full Text Available Local changes in land use result from the decisions and actions of land-users within land systems, which are structured by local and global environmental, economic, political, and cultural contexts. Such cross-scale causation presents a major challenge for developing a general understanding of how local decision-making shapes land-use changes at the global scale. This paper implements a generalized agent-based model (ABM as a virtual laboratory to explore how global and local processes influence the land-use and livelihood decisions of local land-users, operationalized as settlement-level agents, across the landscapes of six real-world test sites. Test sites were chosen in USA, Laos, and China to capture globally-significant variation in population density, market influence, and environmental conditions, with land systems ranging from swidden to commercial agriculture. Publicly available global data were integrated into the ABM to model cross-scale effects of economic globalization on local land-use decisions. A suite of statistics was developed to assess the accuracy of model-predicted land-use outcomes relative to observed and random (i.e. null model landscapes. At four of six sites, where environmental and demographic forces were important constraints on land-use choices, modeled land-use outcomes were more similar to those observed across sites than the null model. At the two sites in which market forces significantly influenced land-use and livelihood decisions, the model was a poorer predictor of land-use outcomes than the null model. Model successes and failures in simulating real-world land-use patterns enabled the testing of hypotheses on land-use decision-making and yielded insights on the importance of missing mechanisms. The virtual laboratory approach provides a practical framework for systematic improvement of both theory and predictive skill in land change science based on a continual process of experimentation and model

  10. Insights from the design and implementation of a single-entry model of referral for total joint replacement surgery: Critical success factors and unanticipated consequences.

    Science.gov (United States)

    Damani, Zaheed; MacKean, Gail; Bohm, Eric; Noseworthy, Tom; Wang, Jenney Meng Han; DeMone, Brie; Wright, Brock; Marshall, Deborah A

    2018-02-01

    Single-entry models (SEMs) in healthcare allow patients to see the next-available provider and have been shown to improve waiting times, access and patient flow for preference-sensitive, scheduled services. The Winnipeg Central Intake Service (WCIS) for hip and knee replacement surgery was implemented to improve access in the Winnipeg Regional Health Authority. This paper describes the system's design/implementation; successes, challenges, and unanticipated consequences. On two occasions, during and following implementation, we interviewed all members of the WCIS project team, including processing engineers, waiting list coordinators, administrators and policy-makers regarding their experiences. We used semi-structured telephone interviews to collect data and qualitative thematic analysis to analyze and interpret the findings. Respondents indicated that the overarching objectives of the WCIS were being met. Benefits included streamlined processes, greater patient access, improved measurement and monitoring of outcomes. Challenges included low awareness, change readiness, and initial participation among stakeholders. Unanticipated consequences included workload increases, confusion around stakeholder expectations and under-reporting of data by surgeons' offices. Critical success factors for implementation included a requirement for clear communication, robust data collection, physician leadership and patience by all, especially implementation teams. Although successfully implemented, key lessons and critical success factors were learned related to change management, which if considered and applied, can reduce unanticipated consequences, improve uptake and benefit new models of care. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Modeling the Severity of Drinking Consequences in First-Year College Women: An Item Response Theory Analysis of the Rutgers Alcohol Problem Index*

    Science.gov (United States)

    Cohn, Amy M.; Hagman, Brett T.; Graff, Fiona S.; Noel, Nora E.

    2011-01-01

    Objective: The present study examined the latent continuum of alcohol-related negative consequences among first-year college women using methods from item response theory and classical test theory. Method: Participants (N = 315) were college women in their freshman year who reported consuming any alcohol in the past 90 days and who completed assessments of alcohol consumption and alcohol-related negative consequences using the Rutgers Alcohol Problem Index. Results: Item response theory analyses showed poor model fit for five items identified in the Rutgers Alcohol Problem Index. Two-parameter item response theory logistic models were applied to the remaining 18 items to examine estimates of item difficulty (i.e., severity) and discrimination parameters. The item difficulty parameters ranged from 0.591 to 2.031, and the discrimination parameters ranged from 0.321 to 2.371. Classical test theory analyses indicated that the omission of the five misfit items did not significantly alter the psychometric properties of the construct. Conclusions: Findings suggest that those consequences that had greater severity and discrimination parameters may be used as screening items to identify female problem drinkers at risk for an alcohol use disorder. PMID:22051212

  12. Some consequences of assuming simple patterns for the treatment effect over time in a linear mixed model.

    Science.gov (United States)

    Bamia, Christina; White, Ian R; Kenward, Michael G

    2013-07-10

    Linear mixed models are often used for the analysis of data from clinical trials with repeated quantitative outcomes. This paper considers linear mixed models where a particular form is assumed for the treatment effect, in particular constant over time or proportional to time. For simplicity, we assume no baseline covariates and complete post-baseline measures, and we model arbitrary mean responses for the control group at each time. For the variance-covariance matrix, we consider an unstructured model, a random intercepts model and a random intercepts and slopes model. We show that the treatment effect estimator can be expressed as a weighted average of the observed time-specific treatment effects, with weights depending on the covariance structure and the magnitude of the estimated variance components. For an assumed constant treatment effect, under the random intercepts model, all weights are equal, but in the random intercepts and slopes and the unstructured models, we show that some weights can be negative: thus, the estimated treatment effect can be negative, even if all time-specific treatment effects are positive. Our results suggest that particular models for the treatment effect combined with particular covariance structures may result in estimated treatment effects of unexpected magnitude and/or direction. Methods are illustrated using a Parkinson's disease trial. Copyright © 2012 John Wiley & Sons, Ltd.

  13. Economic consequences of population size, structure and growth.

    Science.gov (United States)

    Lee, R

    1983-01-01

    There seems to be 4 major approaches to conceptualizing and modeling demographic influences on economic and social welfare. These approaches are combined in various ways to construct richer and more comprehensive models. The basic approaches are: demographic influences on household or family behavior; population growth and reproducible capital; population size and fixed factors; and population and advantages of scale. These 4 models emphasize the supply side effects of population. A few of the ways in which these theories have been combined are sketched. Neoclassical growth models often have been combined with age distributed populations of individuals (or households), assumed to pursue optimal life cycle consumption and saving. In some well known development models, neoclassical growth models for the modern sector are linked by labor markets and migration to fixed factor (land) models of the traditional (agricultural) sector. A whole series of macro simulation models for developed and developing countries was based on single sector neoclassical growth models with age distributed populations. Yet, typically the household level foundations of assumed age distribution effects were not worked out. Simon's (1977) simulation models are in a class by themselves, for they are the only models that attempt to incorporate all the kinds of effects discussed. The economic demography of the individual and family cycle, as it is affected by regimes of fertility, mortality, and nuptiality, taken as given, are considered. The examination touches on many of the purported consequences of aggregate population growth and age composition, since so many of these are based implicitly or explicitly on assertions about micro level behavior. Demographic influences on saving and consumption, on general labor supply and female labor supply, and on problems of youth and old age dependency frequently fall in this category. Finally, attention is focused specifically on macro economic issues in

  14. Multiregional demographic projections in practice: a metropolitan example.

    Science.gov (United States)

    Congdon, P

    1992-01-01

    "This paper examines options for local and regional projections which reflect both demographic interdependencies with jobs and housing at this area scale, and the inapplicability of traditional demographic projection methods to population or areal subdivisions. This context for local demographic projections requires constraints (for example, to job and housing forecasts or to higher area totals), the use of proxy or explanatory indicators to predict demographic rates or totals, and parameterization of demographic schedules, to facilitate comparison across numerous localities and to set future assumptions about demographic components. The traditional framework of self-contained projection by deterministic cohort survival is therefore widened to include regio-scientific and stochastic modelling concepts. The framework for empirical analysis is London [England] and its boroughs." (SUMMARY IN FRE AND GER) excerpt

  15. Modelling the long-term consequences of a hypothetical dispersal of radioactivity in an urban area including remediation alternatives

    DEFF Research Database (Denmark)

    Thiessen, K.M.; Andersson, Kasper Grann; Batandjieva, B.

    2009-01-01

    The Urban Remediation Working Group of the International Atomic Energy Agency's EMRAS (Environmental Modelling for Radiation Safety) program was organized to address issues of remediation assessment modelling for urban areas contaminated with dispersed radionuclides. The present paper describes...... the second of two modelling exercises. This exercise was based on a hypothetical dispersal of radioactivity in an urban area from a radiological dispersal device, with reference surface contamination at selected sites used as the primary input information. Modelling endpoints for the exercise included...... radionuclide concentrations and external dose rates at specified locations, contributions to the dose rates from individual surfaces, and annual and cumulative external doses to specified reference individuals. Model predictions were performed for a "no action" situation (with no remedial measures...

  16. Comparing Absolute Error with Squared Error for Evaluating Empirical Models of Continuous Variables: Compositions, Implications, and Consequences

    Science.gov (United States)

    Gao, J.

    2014-12-01

    Reducing modeling error is often a major concern of empirical geophysical models. However, modeling errors can be defined in different ways: When the response variable is continuous, the most commonly used metrics are squared (SQ) and absolute (ABS) errors. For most applications, ABS error is the more natural, but SQ error is mathematically more tractable, so is often used as a substitute with little scientific justification. Existing literature has not thoroughly investigated the implications of using SQ error in place of ABS error, especially not geospatially. This study compares the two metrics through the lens of bias-variance decomposition (BVD). BVD breaks down the expected modeling error of each model evaluation point into bias (systematic error), variance (model sensitivity), and noise (observation instability). It offers a way to probe the composition of various error metrics. I analytically derived the BVD of ABS error and compared it with the well-known SQ error BVD, and found that not only the two metrics measure the characteristics of the probability distributions of modeling errors differently, but also the effects of these characteristics on the overall expected error are different. Most notably, under SQ error all bias, variance, and noise increase expected error, while under ABS error certain parts of the error components reduce expected error. Since manipulating these subtractive terms is a legitimate way to reduce expected modeling error, SQ error can never capture the complete story embedded in ABS error. I then empirically compared the two metrics with a supervised remote sensing model for mapping surface imperviousness. Pair-wise spatially-explicit comparison for each error component showed that SQ error overstates all error components in comparison to ABS error, especially variance-related terms. Hence, substituting ABS error with SQ error makes model performance appear worse than it actually is, and the analyst would more likely accept a

  17. Mathematical model of the heat transfer process taking into account the consequences of nonlocality in structurally sensitive materials

    Science.gov (United States)

    Kuvyrkin, G. N.; Savelyeva, I. Y.; Kuvshynnikova, D. A.

    2018-04-01

    Creation of new materials based on nanotechnology is an important direction of modern materials science development. Materials obtained using nanotechnology can possess unique physical-mechanical and thermophysical properties, allowing their effective use in structures exposed to high-intensity thermomechanical effects. An important step in creation and use of new materials is the construction of mathematical models to describe the behavior of these materials in a wide range of changes under external effects. The model of heat conduction of structural-sensitive materials is considered with regard to the medium nonlocality effects. The relations of the mathematical model include an integral term describing the spatial nonlocality of the medium. A difference scheme, which makes it possible to obtain a numerical solution of the problem of nonstationary heat conduction with regard to the influence of the medium nonlocality on space, has been developed. The influence of the model parameters on the temperature distributions is analyzed.

  18. Testing relationships from the hierarchical model of intrinsic and extrinsic motivation using flow as a motivational consequence.

    Science.gov (United States)

    Kowal, J; Fortier, M S

    2000-06-01

    The purpose of this study was to test a motivational model based on Vallerand's (1997) Hierarchical Model of Intrinsic and Extrinsic Motivation. This model incorporates situational and contextual motivational variables, and was tested using a time-lagged design. Master's level swimmers (N = 104) completed a questionnaire on two separate occasions. At Time 1, situational social factors (perceptions of success and perceptions of the motivational climate), situational motivational mediators (perceptions of autonomy, competence, and relatedness), situational motivation, and flow were assessed immediately following a swim practice. Contextual measures of these same variables were assessed at Time 2, 1 week later, with the exception of flow. Results of a path analysis supported numerous links in the hypothesized model. Findings are discussed in light of research and theory on motivation and flow.

  19. Evaluation of Current Computer Models Applied in the DOE Complex for SAR Analysis of Radiological Dispersion & Consequences

    Energy Technology Data Exchange (ETDEWEB)

    O' Kula, K. R. [Savannah River Site (SRS), Aiken, SC (United States); East, J. M. [Savannah River Site (SRS), Aiken, SC (United States); Weber, A. H. [Savannah River Site (SRS), Aiken, SC (United States); Savino, A. V. [Savannah River Site (SRS), Aiken, SC (United States); Mazzola, C. A. [Savannah River Site (SRS), Aiken, SC (United States)

    2003-01-01

    The evaluation of atmospheric dispersion/ radiological dose analysis codes included fifteen models identified in authorization basis safety analysis at DOE facilities, or from regulatory and research agencies where past or current work warranted inclusion of a computer model. All computer codes examined were reviewed using general and specific evaluation criteria developed by the Working Group. The criteria were based on DOE Orders and other regulatory standards and guidance for performing bounding and conservative dose calculations. Included were three categories of criteria: (1) Software Quality/User Interface; (2) Technical Model Adequacy; and (3) Application/Source Term Environment. A consensus-based limited quantitative ranking process was used to base an order of model preference as both an overall conclusion, and under specific conditions.

  20. Parametrization consequences of constraining soil organic matter models by total carbon and radiocarbon using long-term field data

    Science.gov (United States)

    Menichetti, Lorenzo; Kätterer, Thomas; Leifeld, Jens

    2016-05-01

    Soil organic carbon (SOC) dynamics result from different interacting processes and controls on spatial scales from sub-aggregate to pedon to the whole ecosystem. These complex dynamics are translated into models as abundant degrees of freedom. This high number of not directly measurable variables and, on the other hand, very limited data at disposal result in equifinality and parameter uncertainty. Carbon radioisotope measurements are a proxy for SOC age both at annual to decadal (bomb peak based) and centennial to millennial timescales (radio decay based), and thus can be used in addition to total organic C for constraining SOC models. By considering this additional information, uncertainties in model structure and parameters may be reduced. To test this hypothesis we studied SOC dynamics and their defining kinetic parameters in the Zürich Organic Fertilization Experiment (ZOFE) experiment, a > 60-year-old controlled cropland experiment in Switzerland, by utilizing SOC and SO14C time series. To represent different processes we applied five model structures, all stemming from a simple mother model (Introductory Carbon Balance Model - ICBM): (I) two decomposing pools, (II) an inert pool added, (III) three decomposing pools, (IV) two decomposing pools with a substrate control feedback on decomposition, (V) as IV but with also an inert pool. These structures were extended to explicitly represent total SOC and 14C pools. The use of different model structures allowed us to explore model structural uncertainty and the impact of 14C on kinetic parameters. We considered parameter uncertainty by calibrating in a formal Bayesian framework. By varying the relative importance of total SOC and SO14C data in the calibration, we could quantify the effect of the information from these two data streams on estimated model parameters. The weighing of the two data streams was crucial for determining model outcomes, and we suggest including it in future modeling efforts whenever SO14C

  1. A Review of Consequences of Poverty on Economic Decision-Making: A Hypothesized Model of a Cognitive Mechanism

    OpenAIRE

    Adamkovič, Matúš; Martončik, Marcel

    2017-01-01

    This review focuses on the issue of poverty affecting economic decision-making. By critically evaluating existing studies, the authors propose a structural model detailing the cognitive mechanism involved in how poverty negatively impacts economic decision-making, and explores evidence supporting the basis for the formation of this model. The suggested mechanism consists of a relationship between poverty and four other factors: (1) cognitive load (e.g., experiencing negative affect and stress...

  2. Modelling the long-term consequences of a hypothetical dispersal of radioactivity in an urban area including remediation alternatives

    International Nuclear Information System (INIS)

    Thiessen, K.M.; Andersson, K.G.; Batandjieva, B.; Cheng, J.-J.; Hwang, W.T.; Kaiser, J.C.; Kamboj, S.; Steiner, M.; Tomas, J.; Trifunovic, D.; Yu, C.

    2009-01-01

    The Urban Remediation Working Group of the International Atomic Energy Agency's EMRAS (Environmental Modelling for Radiation Safety) program was organized to address issues of remediation assessment modelling for urban areas contaminated with dispersed radionuclides. The present paper describes the second of two modelling exercises. This exercise was based on a hypothetical dispersal of radioactivity in an urban area from a radiological dispersal device, with reference surface contamination at selected sites used as the primary input information. Modelling endpoints for the exercise included radionuclide concentrations and external dose rates at specified locations, contributions to the dose rates from individual surfaces, and annual and cumulative external doses to specified reference individuals. Model predictions were performed for a 'no action' situation (with no remedial measures) and for selected countermeasures. The exercise provided an opportunity for comparison of three modelling approaches, as well as a comparison of the predicted effectiveness of various countermeasures in terms of their short-term and long-term effects on predicted doses to humans.

  3. Fitness consequences of maternal and embryonic responses to environmental variation: using reptiles as models for studies of developmental plasticity.

    Science.gov (United States)

    Warner, Daniel A

    2014-11-01

    Environmental factors strongly influence phenotypic variation within populations. The environment contributes to this variation in two ways: (1) by acting as a determinant of phenotypic variation (i.e., plastic responses) and (2) as an agent of selection that "chooses" among existing phenotypes. Understanding how these two environmental forces contribute to phenotypic variation is a major goal in the field of evolutionary biology and a primary objective of my research program. The objective of this article is to provide a framework to guide studies of environmental sources of phenotypic variation (specifically, developmental plasticity and maternal effects, and their adaptive significance). Two case studies from my research on reptiles are used to illustrate the general approaches I have taken to address these conceptual topics. Some key points for advancing our understanding of environmental influences on phenotypic variation include (1) merging laboratory-based research that identifies specific environmental effects with field studies to validate ecological relevance; (2) using controlled experimental approaches that mimic complex environments found in nature; (3) integrating data across biological fields (e.g., genetics, morphology, physiology, behavior, and ecology) under an evolutionary framework to provide novel insights into the underlying mechanisms that generate phenotypic variation; (4) assessing fitness consequences using measurements of survival and/or reproductive success across ontogeny (from embryos to adults) and under multiple ecologically-meaningful contexts; and (5) quantifying the strength and form of natural selection in multiple populations over multiple periods of time to understand the spatial and temporal consistency of phenotypic selection. Research programs that focus on organisms that are amenable to these approaches will provide the most promise for advancing our understanding of the environmental factors that generate the remarkable

  4. Assessment of the consequences of the radioactive contamination of aquatic media and biota. Model testing using Chernobyl data

    International Nuclear Information System (INIS)

    Kryshev, I.; Sazykina, T.; Hoffman, O.; Thiessen, K.

    1996-09-01

    The 'Cooling Pond' scenario was designed to test models for radioactive contamination of aquatic ecosystems, based on data for contamination of different aquatic media and biota due to fallout of radionuclides into the cooling pond of the Chernobyl Nuclear Power Plant. Input data included characteristics of the cooling pond ecosystem (hydrological, hydrochemical, and hydro biological conditions) and estimates of the amounts of 137 Cs in the cooling pond. Predictions were requested in two stages: (1) Calculations of 137 Cs concentrations for comparison against actual measurements, including activities of 137 Cs in the cooling pond water, in layers of sediment, and in fish; (2) Calculations for which actual measurements are not available, including dose and risk estimates for aquatic biota and for humans following hypothetical consumption of contaminated biota. Calculations were performed with the following models: LAKECO (Netherlands), POSOD (USA), LAKEPOND (Romania), WATER (Russia), GIDRO (Russia), and ECOMOD-W (Russia). The total number of scenario calculations was 18. In general, the models tended to overestimate the total doses to fish (as compared to to independent dose estimates made from measured concentrations by the scenario authors) for internal and external exposure, while a number of predictions with different models for the effective dose and risk to humans from fish consumption were in good agreement with independent test estimates. The differences among model predictions were somewhat smaller for the total doses to fish than for the environmental concentrations used in the model testing. The differences among model predictions were very great for the effective doses and risk to humans from fish consumption. This is related to distinct errors in assessments of 137 Cs concentrations in fish. Very few participants obtained good agreement with respect to all criteria of the model testing, i.e., 137 Cs concentrations in the aquatic ecosystem components and

  5. Assessment of the consequences of the radioactive contamination of aquatic media and biota. Model testing using Chernobyl data

    Energy Technology Data Exchange (ETDEWEB)

    Kryshev, I.; Sazykina, T. [SPA Typhoon, Obninsk (Russian Federation); Hoffman, O.; Thiessen, K. [SENES, Oak Ridge, TN (United States)] [and others

    1996-09-01

    The 'Cooling Pond' scenario was designed to test models for radioactive contamination of aquatic ecosystems, based on data for contamination of different aquatic media and biota due to fallout of radionuclides into the cooling pond of the Chernobyl Nuclear Power Plant. Input data included characteristics of the cooling pond ecosystem (hydrological, hydrochemical, and hydro biological conditions) and estimates of the amounts of 137 Cs in the cooling pond. Predictions were requested in two stages: (1) Calculations of 137 Cs concentrations for comparison against actual measurements, including activities of 137 Cs in the cooling pond water, in layers of sediment, and in fish; (2) Calculations for which actual measurements are not available, including dose and risk estimates for aquatic biota and for humans following hypothetical consumption of contaminated biota. Calculations were performed with the following models: LAKECO (Netherlands), POSOD (USA), LAKEPOND (Romania), WATER (Russia), GIDRO (Russia), and ECOMOD-W (Russia). The total number of scenario calculations was 18. In general, the models tended to overestimate the total doses to fish (as compared to to independent dose estimates made from measured concentrations by the scenario authors) for internal and external exposure, while a number of predictions with different models for the effective dose and risk to humans from fish consumption were in good agreement with independent test estimates. The differences among model predictions were somewhat smaller for the total doses to fish than for the environmental concentrations used in the model testing. The differences among model predictions were very great for the effective doses and risk to humans from fish consumption. This is related to distinct errors in assessments of 137 Cs concentrations in fish. Very few participants obtained good agreement with respect to all criteria of the model testing, i.e., 137 Cs concentrations in the aquatic ecosystem

  6. Modeling of the consequences of an air ingress in the vessel on the source term calculation in a severe accident

    International Nuclear Information System (INIS)

    Beuzet, E.

    2010-01-01

    This work deals with severe accidents in nuclear power plants with an air ingress in the vessel. Air, which is very oxidizing, enhances noticeably ruthenium release, due to a high fuel oxidation. Oxygen affinity is decreasing between zircaloy cladding, fuel and ruthenium which is released from fuel as volatile and radio-toxic oxides. The main objective was to develop models for cladding and fuel oxidation and ruthenium release and implement them in the severe accident code MAAP. For each phenomenon, the literature study contributes to establish numerical models, validated against specific experiments. Cladding oxidation by air leads to a dense zirconia layer and, after cracking, a porous zirconia. Its modelling was validated against QUENCH-10 (KIT) and PARAMETER-SF4 (LUCH) experiments and 'NUREG' oxide mass gain law was selected as the best current compromise. Ruthenium release is modelled as an instantaneous oxide volatilisation at the fuel surface, controlled by fuel oxidation, which is itself based on a surface reaction assumption. These models were validated against a selected set of VERCORS (CEA) experiments. Ruthenium release is well-reproduced, particularly for air and steam atmospheres. To finish, an accidental scenario with air ingress in the vessel was simulated: a first value was given for the time needed to completely release ruthenium still present in core and was compared to the other studies. This simulation underlines the high ruthenium release under air conditions. (author)

  7. Demographic and transportation parameters in RADTRAN

    International Nuclear Information System (INIS)

    Brogan, J.D.; Cashwell, J.W.; Neuhauser, K.S.

    1989-01-01

    Recent efforts at Sandia National Laboratories have focused not only on modification of the RADTRAN transportation risk analysis code but also on updating the default parameters for population, land use, and roadway characteristics used by the code. Changes to the code have been discussed earlier in this Conference. This paper summarizes the results of a review of transportation and demographic parameters, performed to complement recent model modifications

  8. Consequence of nanofluid on peristaltic transport of a hyperbolic tangent fluid model in the occurrence of apt (tending) magnetic field

    International Nuclear Information System (INIS)

    Akram, Safia; Nadeem, S.

    2014-01-01

    In the current study, sway of nanofluid on peristaltic transport of a hyperbolic tangent fluid model in the incidence of tending magnetic field has been argued. The governing equations of a nanofluid are first modeled and then simplified under lubrication approach. The coupled nonlinear equations of temperature and nano particle volume fraction are solved analytically using a homotopy perturbation technique. The analytical solution of the stream function and pressure gradient are carried out using perturbation technique. The graphical results of the problem under discussion are also being brought under consideration to see the behavior of various physical parameters. - Highlights: • The main motivation of this work is that we want to see the behavior of nanofluids in peristaltic flows. • In literature few articles are available on this, but no article is available in asymmetric channel on the new fluid model hyperbolic tangent fluid. • So we want to fill the gap in literature studying this

  9. A Review of Consequences of Poverty on Economic Decision-Making: A Hypothesized Model of a Cognitive Mechanism

    Directory of Open Access Journals (Sweden)

    Matúš Adamkovič

    2017-10-01

    Full Text Available This review focuses on the issue of poverty affecting economic decision-making. By critically evaluating existing studies, the authors propose a structural model detailing the cognitive mechanism involved in how poverty negatively impacts economic decision-making, and explores evidence supporting the basis for the formation of this model. The suggested mechanism consists of a relationship between poverty and four other factors: (1 cognitive load (e.g., experiencing negative affect and stress; (2 executive functions (e.g., attention, working memory, and self-control; (3 intuition/deliberation in decision-making; and (4 economic decision-making (e.g., time-discounting and risk preference, with a final addition of financial literacy as a covariate. This paper focuses on shortfalls in published research, and delves further into the proposed model.

  10. Consequence of nanofluid on peristaltic transport of a hyperbolic tangent fluid model in the occurrence of apt (tending) magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Akram, Safia, E-mail: safia_akram@yahoo.com [Department of Basic Sciences, MCS, National University of Sciences and Technology, Rawalpindi 46000 (Pakistan); Nadeem, S. [Department of Mathematics, Quaid-i-Azam University 45320, Islamabad 44000 (Pakistan)

    2014-05-01

    In the current study, sway of nanofluid on peristaltic transport of a hyperbolic tangent fluid model in the incidence of tending magnetic field has been argued. The governing equations of a nanofluid are first modeled and then simplified under lubrication approach. The coupled nonlinear equations of temperature and nano particle volume fraction are solved analytically using a homotopy perturbation technique. The analytical solution of the stream function and pressure gradient are carried out using perturbation technique. The graphical results of the problem under discussion are also being brought under consideration to see the behavior of various physical parameters. - Highlights: • The main motivation of this work is that we want to see the behavior of nanofluids in peristaltic flows. • In literature few articles are available on this, but no article is available in asymmetric channel on the new fluid model hyperbolic tangent fluid. • So we want to fill the gap in literature studying this.

  11. A Review of Consequences of Poverty on Economic Decision-Making: A Hypothesized Model of a Cognitive Mechanism.

    Science.gov (United States)

    Adamkovič, Matúš; Martončik, Marcel

    2017-01-01

    This review focuses on the issue of poverty affecting economic decision-making. By critically evaluating existing studies, the authors propose a structural model detailing the cognitive mechanism involved in how poverty negatively impacts economic decision-making, and explores evidence supporting the basis for the formation of this model. The suggested mechanism consists of a relationship between poverty and four other factors: (1) cognitive load (e.g., experiencing negative affect and stress); (2) executive functions (e.g., attention, working memory, and self-control); (3) intuition/deliberation in decision-making; and (4) economic decision-making (e.g., time-discounting and risk preference), with a final addition of financial literacy as a covariate. This paper focuses on shortfalls in published research, and delves further into the proposed model.

  12. An Online Process Model of Second-Order Cultivation Effects: How Television Cultivates Materialism and Its Consequences for Life Satisfaction

    Science.gov (United States)

    Shrum, L. J.; Lee, Jaehoon; Burroughs, James E.; Rindfleisch, Aric

    2011-01-01

    Two studies investigated the interrelations among television viewing, materialism, and life satisfaction, and their underlying processes. Study 1 tested an online process model for television's cultivation of materialism by manipulating level of materialistic content. Viewing level influenced materialism, but only among participants who reported…

  13. Demographics.

    Science.gov (United States)

    Gillis, Artha J; Bath, Eraka

    2016-01-01

    There is a large proportion of minority youth involved in the juvenile justice system. Disproportionate minority contact (DMC) occurs when the proportion of any ethnic group is higher at any given stage in the juvenile justice process than the proportion of this group in the general population. There are several theories explaining the presence and persistence of DMC. This article reviews the history of DMC and the theories and implications of this problem. It discusses several targets for interventions designed to reduce DMC and offer resources in this area. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Modeling the Effects of Duration and Size of the Control Zones on the Consequences of a Hypothetical African Swine Fever Epidemic in Denmark

    DEFF Research Database (Denmark)

    Halasa, Tariq; Bøtner, Anette; Mortensen, Sten

    2018-01-01

    control an epidemic of ASF. A previously published and well documented simulation model for ASF virus spread between herds was used to examine the epidemiologic and economic impacts of the duration and size of the control zones around affected herds. In the current study, scenarios were run, where......African swine fever (ASF) is a notifiable infectious disease. The disease is endemic in certain regions in Eastern Europe constituting a risk of ASF spread toward Western Europe. Therefore, as part of contingency planning, it is important to continuously explore strategies that can effectively...... or clinical and serological surveillance of herds within the zones. Sensitivity analysis was conducted on influential input parameters in the model. The model predicts that reducing the duration of the protection and surveillance zones has no impact on the epidemiological consequences of the epidemics, while...

  15. Inverse modelling for real-time estimation of radiological consequences in the early stage of an accidental radioactivity release.

    Science.gov (United States)

    Pecha, Petr; Šmídl, Václav

    2016-11-01

    A stepwise sequential assimilation algorithm is proposed based on an optimisation approach for recursive parameter estimation and tracking of radioactive plume propagation in the early stage of a radiation accident. Predictions of the radiological situation in each time step of the plume propagation are driven by an existing short-term meteorological forecast and the assimilation procedure manipulates the model parameters to match the observations incoming concurrently from the terrain. Mathematically, the task is a typical ill-posed inverse problem of estimating the parameters of the release. The proposed method is designated as a stepwise re-estimation of the source term release dynamics and an improvement of several input model parameters. It results in a more precise determination of the adversely affected areas in the terrain. The nonlinear least-squares regression methodology is applied for estimation of the unknowns. The fast and adequately accurate segmented Gaussian plume model (SGPM) is used in the first stage of direct (forward) modelling. The subsequent inverse procedure infers (re-estimates) the values of important model parameters from the actual observations. Accuracy and sensitivity of the proposed method for real-time forecasting of the accident propagation is studied. First, a twin experiment generating noiseless simulated "artificial" observations is studied to verify the minimisation algorithm. Second, the impact of the measurement noise on the re-estimated source release rate is examined. In addition, the presented method can be used as a proposal for more advanced statistical techniques using, e.g., importance sampling. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Demographics in Astronomy and Astrophysics

    Science.gov (United States)

    Ulvestad, James S.

    2011-05-01

    Astronomy has been undergoing a significant demographic shift over the last several decades, as shown by data presented in the 2000 National Research Council (NRC) report "Federal Funding of Astronomical Research," and the 2010 NRC report, "New Worlds, New Horizons in Astronomy and Astrophysics." For example, the number of advertised postdoctoral positions in astronomy has increased much more rapldly than the number of faculty positions, contributing to a holding pattern of early-career astronomers in multiple postdoctoral positions. This talk will summarize some of the current demographic trends in astronomy, including information about gender and ethnic diversity, and describe some of the possible implications for the future. I thank the members of the Astro2010 Demographics Study Group, as well as numerous white-paper contributors to Astro2010, for providing data and analyses.

  17. Social demographic change and autism.

    Science.gov (United States)

    Liu, Kayuet; Zerubavel, Noam; Bearman, Peter

    2010-05-01

    Parental age at child's birth--which has increased for U.S. children in the 1992-2000 birth cohorts--is strongly associated with an increased risk of autism. By turning a social demographic lens on the historical patterning of concordance among twin pairs, we identify a central mechanism for this association: de novo mutations, which are deletions, insertions, and duplications of DNA in the germ cells that are not present in the parents' DNA. Along the way, we show that a demographic eye on the rising prevalence of autism leads to three major discoveries. First, the estimated heritability of autism has been dramatically overstated. Second, heritability estimates can change over remarkably short periods of time because of increases in germ cell mutations. Third, social demographic change can yield genetic changes that, at the population level, combine to contribute to the increased prevalence of autism.

  18. Inverse modelling for real-time estimation of radiological consequences in the early stage of an accidental radioactivity release

    Czech Academy of Sciences Publication Activity Database

    Pecha, Petr; Šmídl, Václav

    2016-01-01

    Roč. 164, č. 1 (2016), s. 377-394 ISSN 0265-931X R&D Projects: GA MŠk(CZ) 7F14287; GA MV VG20102013018 Institutional support: RVO:67985556 Keywords : Inverse modelling * recursive radioactive plume tracking * Improvement of population protection * monitoring network capability Subject RIV: AQ - Safety, Health Protection, Human - Machine Impact factor: 2.310, year: 2016 http://library.utia.cas.cz/separaty/2016/AS/pecha-0460631.pdf

  19. Land use and demographic grids in Cosyma

    International Nuclear Information System (INIS)

    Robinson, C.A.; Hasemann, I.

    1991-01-01

    The spatial distribution of the population, agricultural production, economic activity, and the position of land and sea, are important elements of accident consequence codes. These data are necessary in evaluating the health effects within the population arising from the external dose, inhalation and ingestion pathways. These distributions are also essential in calculating the economic impact of implementing countermeasures, such as relocation and food bans. This paper includes a discussion of the agricultural production and population distribution information available for EC countries, their resolution, availability and sources. The gridded data included in the COSYMA system are described. Particular aspects, such as the difficulties involved with using economic land use information, are also explained. Future developments, and their effect on the requirements for land use and demographic grids, are outlined

  20. CEC workshop on methods for assessing the offsite radiological consequences of nuclear accidents

    International Nuclear Information System (INIS)

    Luykx, F.; Sinnaeve, J.

    1986-01-01

    On Apr 15-19, 1985, in Luxembourg, the Commission of the European Communities (CEC), in collaboration with the Kernforschungszentrum Karlsruhe (KfK), Federal Republic of Germany, and