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. Demographic consequences of defeating aging.

    Science.gov (United States)

    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 of this study is that population changes are surprisingly slow in their response to a dramatic life extension. For example, we applied the cohort-component method of population projections to 2005 Swedish population for several scenarios of life extension and a fertility schedule observed in 2005. Even for very long 100-year projection horizon, with the most radical life extension scenario (assuming no aging at all after age 60), the total population increases by 22% only (from 9.1 to 11.0 million). Moreover, if some members of society reject to use new anti-aging technologies for some religious or any other reasons (inconvenience, non-compliance, fear of side effects, costs, etc.), then the total population size may even decrease over time. Thus, even in the case of the most radical life extension scenario, population growth could be relatively slow and may not necessarily lead to overpopulation. Therefore, the real concerns should be placed not on the threat of catastrophic population consequences (overpopulation), but rather on such potential obstacles to a success of biomedical war on aging, as scientific, organizational, and financial limitations.

  3. 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.

  4. Demographic Consequences of the Stalingrad Battle

    Directory of Open Access Journals (Sweden)

    Evgeniy F. Krinko

    2018-02-01

    Full Text Available The first information about the losses of the Red Army and the Wehrmacht in the Battle of Stalingrad, the deaths of the civilian population of the Stalingrad region during the Nazi occupation were published back in the years of the Great Patriotic War. Later many authors investigated these questions. In the early 1990s, Soviet losses were calculated by a group of specialists of the General Staff under the leadership of Colonel General G. F. Krivosheev. However, there are alternative points of view on this issue. In general, the demographic consequences of the Battle of Stalingrad as a complex scientific problem have not been sufficiently studied. The authors of the article consider different types of losses, mention major military associations and units that took part in the fights for Stalingrad, as well as the number of soldiers in military units. The special attention is paid to the losses of civilian population. According to the most conservative estimates, the military losses of both parties in the Stalingrad battle amounted to at least 2–2.5 million people. The population of the Stalingrad region declined as a result of evacuation, hostilities and occupation by more than 0.5 million people, or nearly by a quarter. Mass losses led to significant deformations in the demographic structure of the population of the Stalingrad and neighboring regions. The number of working age men suffere the especially sharp decline. These deformations had determined the unfavorable trends in the demographic development of the region for many decades. In the introductory part of the paper E.F. Krinko describes the main types of losses and correlation of military forces by the beginning of the Stalingrad Battle. The conclusions made by the author summarize the overall research results. M. V. Medvedev reveals specific types of military and civilian losses suffered as a result of the Stalingrad Battle.

  5. Demographic and medical consequences of the postponement of parenthood

    DEFF Research Database (Denmark)

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

    2012-01-01

    BACKGROUND Across the developed world couples are postponing parenthood. This review assesses the consequences of delayed family formation from a demographic and medical perspective. One main focus is on the quantitative importance of pregnancy postponement. METHODS Medical and social science...

  6. 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)

  7. [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

  8. 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...

  9. 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.

  10. 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.

  11. 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

  12. 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 ...

  13. 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.

  14. Causes and consequences of demographic development in the territory of Velebit Nature Park, 1857–2001

    OpenAIRE

    PEJNOVIĆ, DANE; HUSANOVIĆ-PEJNOVIĆ, DRAGICA

    2008-01-01

    Abstract Background and Purpose: The focus of this paper is the population and level of human habitation in Velebit Nature Park. The objective is to show the causes underlying demographic development, including population figures from 1857 to 2001 and overall population trends from 1961 to 2001 (population dynamics, natural trends and migrations) and their consequences in the contemporary habitation structure (settlements based on size and age composition of their populations). Resear...

  15. 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

  16. 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

  17. The double edged sword: The demographic consequences of the evolution of self-fertilization.

    Science.gov (United States)

    Abu Awad, Diala; Billiard, Sylvain

    2017-05-01

    Phylogenies indicate that the transition from outcrossing to selfing is frequent, with selfing populations being more prone to extinction. The rates of transition to selfing and extinction, acting on different timescales, could explain the observed distributions of extant selfing species among taxa. However, phylogenetic and theoretical studies consider these mechanisms independently, that is transitions do not cause extinction. Here, we theoretically explore the demographic consequences of the evolution of self-fertilization. Deleterious mutations and mutations modifying the selfing rate are recurrently introduced and the number of offspring depends on individual fitness, allowing for a demographic feedback. We show that mutational meltdowns can be triggered in populations evolving near strict selfing. Populations having survived a demographic crash are more stable than ancestral outcrossing populations once deleterious mutations are purged. The relatively rapid time-scales at which extinctions occur indicate that during evolutionary transitions the accumulation of deleterious mutations may not be the cause of extinctions observed on longer time scales, but could lead to the underestimation of transition rates from outcrossing to selfing. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  18. Community-level demographic consequences of urbanization: an ecological network approach.

    Science.gov (United States)

    Rodewald, Amanda D; Rohr, Rudolf P; Fortuna, Miguel A; Bascompte, Jordi

    2014-11-01

    Ecological networks are known to influence ecosystem attributes, but we poorly understand how interspecific network structure affect population demography of multiple species, particularly for vertebrates. Establishing the link between network structure and demography is at the crux of being able to use networks to understand population dynamics and to inform conservation. We addressed the critical but unanswered question, does network structure explain demographic consequences of urbanization? We studied 141 ecological networks representing interactions between plants and nesting birds in forests across an urbanization gradient in Ohio, USA, from 2001 to 2011. Nest predators were identified by video-recording nests and surveyed from 2004 to 2011. As landscapes urbanized, bird-plant networks were more nested, less compartmentalized and dominated by strong interactions between a few species (i.e. low evenness). Evenness of interaction strengths promoted avian nest survival, and evenness explained demography better than urbanization, level of invasion, numbers of predators or other qualitative network metrics. Highly uneven networks had approximately half the nesting success as the most even networks. Thus, nest survival reflected how urbanization altered species interactions, particularly with respect to how nest placement affected search efficiency of predators. The demographic effects of urbanization were not direct, but were filtered through bird-plant networks. This study illustrates how network structure can influence demography at the community level and further, that knowledge of species interactions and a network approach may be requisite to understanding demographic responses to environmental change. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

  19. The consequences of not accounting for background selection in demographic inference.

    Science.gov (United States)

    Ewing, Gregory B; Jensen, Jeffrey D

    2016-01-01

    Recently, there has been increased awareness of the role of background selection (BGS) in both data analysis and modelling advances. However, BGS is still difficult to take into account because of tractability issues with simulations and difficulty with nonequilibrium demographic models. Often, simple rescaling adjustments of effective population size are used. However, there has been neither a proper characterization of how BGS could bias or shift inference when not properly taken into account, nor a thorough analysis of whether rescaling is a sufficient solution. Here, we carry out extensive simulations with BGS to determine biases and behaviour of demographic inference using an approximate Bayesian approach. We find that results can be positively misleading with significant bias, and describe the parameter space in which BGS models replicate observed neutral nonequilibrium expectations. © 2015 John Wiley & Sons Ltd.

  20. [Human resources planning: the use of demographic-economic models].

    Science.gov (United States)

    Daubon, R E

    1980-01-01

    This article provides an overview of the evolution of employment at different stages of economic development and describes the employment situation in developing countries, suggesting future trends and means of improvement. The lack of authentic development is reflected in the problem of employment of both natural and human resources in Third World countries. Their occupational structures may be examined in 2 periods, 1 in which a certain pretransitional equilibrium was still observed, and the other following the beginning of industrialization. With increased population growth and the application of development strategies favoring urban areas and manufacturing, a series of imbalances were introduced which had as 1 consequence an ever widening income gap between rural areas, cities, and developed countries. Rural stagnation and population pressure ultimately led to massive urban migration in many areas, swelling the cities and creating an "informal sector" of underemployed persons in marginal activities of low productivity. By 2050, the world labor force will have increased from its present 1.7 billion workers to 3.8 billion, of which only 660 million will be in presently developed countries. Each country must plan the best use of its human resources, and must include employment planning in overall development planning. The development of economic-demographic models, adapted to the context of each country, can be a valuable tool in planning. Various types of economic-demographic models and their uses are described and differentiated. Economic-demographic models of employment have 3 main parts, demography, economy, and training. Their use in the analysis of the impact of specific variables on employment, of policies, and of general strategies is described. Finally, the characteristics and uses of MODEMP, an economic-demographic model created for analysis of labor force and employment problems in Peru, are described.

  1. 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

  2. Drivers and demographic consequences of seasonal mass changes in an alpine ungulate.

    Science.gov (United States)

    Douhard, Mathieu; Guillemette, Simon; Festa-Bianchet, Marco; Pelletier, Fanie

    2018-03-01

    We know little about the determinants and demographic consequences of the marked seasonal mass changes exhibited by many northern and alpine mammals. We analysed 43 years of data on individual winter mass loss (the difference between mass in early June and mass in mid-September the previous year) and summer mass gain (the difference between mass in mid-September and in early June of the same year) in adult bighorn sheep (Ovis canadensis). We calculated relative seasonal mass change as a proportion of individual body mass at the start of each season. We first examined the effects of weather and population density on relative changes in body mass. We then assessed the consequences of relative seasonal mass changes on reproduction. Mean April-May temperature was the main driver of relative seasonal mass changes: warm springs reduced both relative winter mass loss and summer mass gain of both sexes, likely partially due to a trade-off between growth rate of plants and duration of access to high-quality forage. Because these effects cancelled each other, spring temperature did not influence mass in mid-September. Mothers that lost relatively more mass during the winter had lambs that gained less mass during summer, likely because these females allocated fewer resources to lactation. Winter survival of lambs increased with their summer mass gain. In males, relative mass loss during winter, which includes the rut, did not influence the probability of siring at least one lamb, possibly indicating that greater mating effort did not necessarily translate into greater reproductive success. Our findings improve our understanding of how weather influences recruitment and underline the importance of cryptic mechanisms behind the effects of climate change on demographic traits. © 2018 by the Ecological Society of America.

  3. [Economic adjustment and its demographic consequences in Latin America: an overview].

    Science.gov (United States)

    Bajraj, R F; Bravo, J H

    1994-06-01

    This work reviews the available literature on short and medium term demographic responses to the economic adjustment processes occurring in Latin America during the 1980s. The first section describes the immediate causes and scope of the economic crisis of the 1980s in Latin America and the measures taken to correct imbalances. An external crisis rendered the current accounts deficit of the early 1980s no longer sustainable, interest rates and commercial conditions deteriorated, and a recessive adjustment of enormous magnitude occurred. The term "adjustment" covers a wide and varied array of economic changes, fiscal and social policy reforms, and changes in international commerce. The structural adjustment measures caused deterioration in investment and in equity. Real purchasing power declined more than per capita product in most Latin American countries between 1980 and 1990. Primary income distribution underwent regressive changes. In most cases the deterioration was not compensated by social spending. As a result of the fiscal adjustment and reduced public sector spending, per capita investment in health and education was less in 1990 than in 1980 in almost all countries. The demographic consequences of the adjustment processes are difficult to gauge precisely because the experiences of individual countries were heterogeneous and because no single definition of adjustment exists that would serve as a point of reference for comparison of situations without adjustment or with different types of adjustment. Nevertheless, some studies have attempted to specify terms of comparison. Some have compared conditions before the crisis or adjustments with conditions later, and others have analyzed short term fluctuations in demographic variables from their medium or long term trends. Such works suggest that nuptiality is the variable responding most intensely, systematically, and immediately to short term economic fluctuations. Fertility also appears to have responded

  4. 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...

  5. [Political impact of demographic change in Germany. A summary view of the causes and consequences of demographic change in Germany and Europe].

    Science.gov (United States)

    Birg, Herwig

    2009-01-01

    In Germany, the increase of life expectancy and the rapid decline of fertility started in the 19th century. The decline of the total fertility rate accelerated since the last decade of the 19th century when the social security system was established in the framework of the social reforms introduced by Bismarck. The process of population change is still going on. Its main demographic dimensions are demographic ageing, population decline, and the internationalisation of the population process by in-migration. The societal consequences are conflicts between the old and young generations as well as conflicts within each generation between the population groups with and without children. The economic impact of demographic change is a reduction of wealth, caused by a lower growth rate of the national product and by a reduction of the growth rate of the per capita income. Copyright 2009 S. Karger AG, Basel.

  6. Demographic consequences of heavy metals and persistent organic pollutants in a vulnerable long-lived bird, the wandering albatross.

    Science.gov (United States)

    Goutte, Aurélie; Barbraud, Christophe; Meillère, Alizée; Carravieri, Alice; Bustamante, Paco; Labadie, Pierre; Budzinski, Hélène; Delord, Karine; Cherel, Yves; Weimerskirch, Henri; Chastel, Olivier

    2014-07-22

    Seabirds are top predators of the marine environment that accumulate contaminants over a long life-span. Chronic exposure to pollutants is thought to compromise survival rate and long-term reproductive outputs in these long-lived organisms, thus inducing population decline. However, the demographic consequences of contaminant exposure are largely theoretical because of the dearth of long-term datasets. This study aims to test whether adult survival rate, return to the colony and long-term breeding performance were related to blood mercury (Hg), cadmium (Cd) and persistent organic pollutants (POPs), by using a capture-mark-recapture dataset on the vulnerable wandering albatross Diomedea exulans. We did not find evidence for any effect of contaminants on adult survival probability. However, blood Hg and POPs negatively impacted long-term breeding probability, hatching and fledging probabilities. The proximate mechanisms underlying these deleterious effects are likely multifaceted, through physiological perturbations and interactions with reproductive costs. Using matrix population models, we projected a demographic decline in response to an increase in Hg or POPs concentrations. This decline in population growth rate could be exacerbated by other anthropogenic perturbations, such as climate change, disease and fishery bycatch. This study gives a new dimension to the overall picture of environmental threats to wildlife populations. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  7. Demographic consequences of heavy metals and persistent organic pollutants in a vulnerable long-lived bird, the wandering albatross

    Science.gov (United States)

    Goutte, Aurélie; Barbraud, Christophe; Meillère, Alizée; Carravieri, Alice; Bustamante, Paco; Labadie, Pierre; Budzinski, Hélène; Delord, Karine; Cherel, Yves; Weimerskirch, Henri; Chastel, Olivier

    2014-01-01

    Seabirds are top predators of the marine environment that accumulate contaminants over a long life-span. Chronic exposure to pollutants is thought to compromise survival rate and long-term reproductive outputs in these long-lived organisms, thus inducing population decline. However, the demographic consequences of contaminant exposure are largely theoretical because of the dearth of long-term datasets. This study aims to test whether adult survival rate, return to the colony and long-term breeding performance were related to blood mercury (Hg), cadmium (Cd) and persistent organic pollutants (POPs), by using a capture–mark–recapture dataset on the vulnerable wandering albatross Diomedea exulans. We did not find evidence for any effect of contaminants on adult survival probability. However, blood Hg and POPs negatively impacted long-term breeding probability, hatching and fledging probabilities. The proximate mechanisms underlying these deleterious effects are likely multifaceted, through physiological perturbations and interactions with reproductive costs. Using matrix population models, we projected a demographic decline in response to an increase in Hg or POPs concentrations. This decline in population growth rate could be exacerbated by other anthropogenic perturbations, such as climate change, disease and fishery bycatch. This study gives a new dimension to the overall picture of environmental threats to wildlife populations. PMID:24920477

  8. 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,

  9. 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

  10. 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.

  11. 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

  12. 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....

  13. Long-term demographic consequences of habitat fragmentation to a tropical understory bird community

    Science.gov (United States)

    Korfanta, N.M.; Newmark, W.D.; Kauffman, M.J.

    2012-01-01

    Tropical deforestation continues to cause population declines and local extinctions in centers of avian diversity and endemism. Although local species extinctions stem from reductions in demographic rates, little is known about how habitat fragmentation influences survival of tropical bird populations or the relative importance of survival and fecundity in ultimately shaping communities. We analyzed 22 years of mark-recapture data to assess how fragmentation influenced apparent survival, recruitment, and realized population growth rate within 22 forest understory bird species in the Usambara Mountains, Tanzania. This represents the first such effort, in either tropical or temperate systems, to characterize the effect of deforestation on avian survival across such a broad suite of species. Long-term demographic analysis of this suite of species experiencing the same fragmented environment revealed considerable variability in species' responses to fragmentation, in addition to general patterns that emerged from comparison among species. Across the understory bird community as a whole, we found significantly lower apparent survival and realized population growth rate in small fragments relative to large, demonstrating fragmentation effects to demographic rates long after habitat loss. Demographic rates were depressed across five feeding guilds, suggesting that fragmentation sensitivity was not limited to insectivores. Seniority analyses, together with a positive effect of fragmentation on recruitment, indicated that depressed apparent survival was the primary driver of population declines and observed extinctions. We also found a landscape effect, with lower vital rates in one mountain range relative to another, suggesting that fragmentation effects may add to other large-scale drivers of population decline. Overall, realized population growth rate (λ) estimates were < 1 for most species, suggesting that future population persistence even within large forest

  14. Long-term demographic consequences of habitat fragmentation to a tropical understory bird community.

    Science.gov (United States)

    Korfanta, Nicole M; Newmark, William D; Kauffman, Matthew J

    2012-12-01

    Tropical deforestation continues to cause population declines and local extinctions in centers of avian diversity and endemism. Although local species extinctions stem from reductions in demographic rates, little is known about how habitat fragmentation influences survival of tropical bird populations or the relative importance of survival and fecundity in ultimately shaping communities. We analyzed 22 years of mark-recapture data to assess how fragmentation influenced apparent survival, recruitment, and realized population growth rate within 22 forest understory bird species in the Usambara Mountains, Tanzania. This represents the first such effort, in either tropical or temperate systems, to characterize the effect of deforestation on avian survival across such a broad suite of species. Long-term demographic analysis of this suite of species experiencing the same fragmented environment revealed considerable variability in species' responses to fragmentation, in addition to general patterns that emerged from comparison among species. Across the understory bird community as a whole, we found significantly lower apparent survival and realized population growth rate in small fragments relative to large, demonstrating fragmentation effects to demographic rates long after habitat loss, Demographic rates were depressed across five feeding guilds, suggesting that fragmentation sensitivity was not limited to insectivores. Seniority analyses, together with a positive effect of fragmentation on recruitment, indicated that depressed apparent survival was the primary driver of population declines and observed extinctions. We also found a landscape effect, with lower vital rates in one mountain range relative to another, suggesting that fragmentation effects may add to other large-scale drivers of population decline. Overall, realized population growth rate (lambda) estimates were fragments, is uncertain in this biodiversity hotspot.

  15. 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.

  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. 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.

  18. 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.

  19. Demographic consequences of migratory stopover: linking red knot survival to horseshoe crab spawning abundance

    Science.gov (United States)

    McGowan, Conor P.; Hines, James E.; Nichols, James D.; Lyons, James E.; Smith, David; Kalasz, Kevin S.; Niles, Lawrence J.; Dey, Amanda D.; Clark, Nigel A.; Atkinson, Philip W.; Minton, Clive D.T.; Kendall, William

    2011-01-01

    Understanding how events during one period of the annual cycle carry over to affect survival and other fitness components in other periods is essential to understanding migratory bird demography and conservation needs. Previous research has suggested that western Atlantic red knot (Calidris canutus rufa) populations are greatly affected by horseshoe crab (Limulus polyphemus) egg availability at Delaware Bay stopover sites during their spring northward migration. We present a mass-based multistate, capturerecapture/resighting model linking (1) red knot stopover mass gain to horseshoe crab spawning abundance and (2) subsequent apparent annual survival to mass state at the time of departure from the Delaware Bay stopover area. The model and analysis use capture-recapture/resighting data with over 16,000 individual captures and 13,000 resightings collected in Delaware Bay over a 12 year period from 1997–2008, and the results are used to evaluate the central management hypothesis that red knot populations can be influenced by horseshoe crab harvest regulations as part of a larger adaptive management effort. Model selection statistics showed support for a positive relationship between horseshoe crab spawning abundance during the stopover and the probability of red knots gaining mass (parameter coefficient from the top model b = 1.71, SE = 0.46). Our analyses also supported the link between red knot mass and apparent annual survival, although average estimates for the two mass classes differed only slightly. The addition of arctic snow depth as a covariate influencing apparent survival improved the fit of the data to the models (parameter coefficient from the top model b = 0.50, SE = 0.08). Our results indicate that managing horseshoe crab resources in the Delaware Bay has the potential to improve red knot population status.

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

    OpenAIRE

    N. V. Vishnyakov; D. A. Semenova

    2016-01-01

    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 g...

  1. 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...

  2. 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.

  3. 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.

  4. 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

  5. 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.

  6. 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.

  7. 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)

  8. Antecedents and Consequences of Business Model Innovation

    DEFF Research Database (Denmark)

    Waldner, Florian; Poetz, Marion; Grimpe, Christoph

    2015-01-01

    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...... 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......, in the emergent stage. Competitive industry pressures turn out to be negatively related to the degree of business model innovation. Moreover, we find that the degree of a firm’s business model innovation, conditional on it having introduced a new product or process recently, positively influences innovation...

  9. 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.

  10. 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

  11. Observational consequences of a dark interaction model

    Energy Technology Data Exchange (ETDEWEB)

    Campos, M. de, E-mail: campos@if.uff.b [Roraima Federal University (UFRR), Paricarana, Boa Vista, RO (Brazil). Physics Dept.

    2010-12-15

    We study a model with decay of dark energy and creation of the dark matter particles. We integrate the field equations and find the transition redshift where the evolution process of the universe change the accelerated expansion, and discuss the luminosity distance, acoustic oscillations and the state finder parameters. (author)

  12. 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

  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. 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

  15. 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.

  16. 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...

  17. Demographic and Predeparture Factors Associated with Drinking and Alcohol-Related Consequences for College Students Completing Study Abroad Experiences

    Science.gov (United States)

    Pedersen, Eric R.; Skidmore, Jessica R.; Aresi, Giovanni

    2014-01-01

    Objective: Study abroad students are at risk for increased and problematic drinking behavior. As few efforts have been made to examine this at-risk population, the authors predicted drinking and alcohol-related consequences abroad from predeparture and site-specific factors. Participants: The sample consisted of 339 students completing study…

  18. 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.

  19. 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.

  20. 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

  1. Demographic consequences of disease in a habitat-forming seaweed and impacts on interactions between natural enemies.

    Science.gov (United States)

    Campbell, Alexandra H; Vergés, Adriana; Steinberg, Peter D

    2014-01-01

    Diseases affecting natural ecosystems are increasing in frequency and severity, but unless obviously catastrophic, the consequences of disease outbreaks are often overlooked, relative to other ecological processes (e.g., predation, competition). Disease can have profound effects on individuals and can also strongly influence interactions between infected hosts and their natural enemies. We investigated whether a novel bleaching disease affected the survival or performance of a habitat-forming red seaweed, Delisea pulchra. In addition, we investigated bidirectional, multipartite interactions between this seaweed host, its pathogens, and consumers. Although we found no negative impacts of disease on survival of D. pulchra, bleaching had substantial, negative consequences for affected individuals, including a dramatic drop in fecundity and a significant decrease in size. In the first direct demonstration of bacterial disease-mediated herbivory of seaweeds, herbivores generally preferred to consume bleached tissue in feeding trials, and we also found higher densities of herbivores on bleached than co-occurring, healthy algae at sites where herbivores were abundant. In a conceptually reciprocal test of the effects of herbivores on infection, we showed that simulated herbivory increased susceptibility to bleaching when algae were also exposed to cultures of a bacterial pathogen. Given the high proportions of D. pulchra affected by bleaching during peak periods, the impacts of this disease are likely to have important implications at the population level. This work highlights complex interactions between habitat-forming organisms and their natural enemies and further emphasizes the need to consider disease in ecological research.

  2. 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.

  3. 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.

  4. 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.

  5. 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

  6. Demographics of reintroduced populations: estimation, modeling, and decision analysis

    Science.gov (United States)

    Converse, Sarah J.; Moore, Clinton T.; Armstrong, Doug P.

    2013-01-01

    Reintroduction can be necessary for recovering populations of threatened species. However, the success of reintroduction efforts has been poorer than many biologists and managers would hope. To increase the benefits gained from reintroduction, management decision making should be couched within formal decision-analytic frameworks. Decision analysis is a structured process for informing decision making that recognizes that all decisions have a set of components—objectives, alternative management actions, predictive models, and optimization methods—that can be decomposed, analyzed, and recomposed to facilitate optimal, transparent decisions. Because the outcome of interest in reintroduction efforts is typically population viability or related metrics, models used in decision analysis efforts for reintroductions will need to include population models. In this special section of the Journal of Wildlife Management, we highlight examples of the construction and use of models for informing management decisions in reintroduced populations. In this introductory contribution, we review concepts in decision analysis, population modeling for analysis of decisions in reintroduction settings, and future directions. Increased use of formal decision analysis, including adaptive management, has great potential to inform reintroduction efforts. Adopting these practices will require close collaboration among managers, decision analysts, population modelers, and field biologists.

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

    DEFF Research Database (Denmark)

    Felbo, Bjarke; Sundsøy, Pål; Pentland, Alex

    2017-01-01

    nature of the patterns in the data. From high-level assumptions we design a data representation and convolutional network architecture for modeling patterns within a week. We then examine three strategies for aggregating patterns across weeks and show that our method reaches state-of-the-art accuracy...

  8. How best to collect demographic data for PVA models

    Czech Academy of Sciences Publication Activity Database

    Münzbergová, Zuzana; Ehrlén, J.

    2005-01-01

    Roč. 42, - (2005), s. 1115-1120 ISSN 0021-8901 R&D Projects: GA ČR GA206/02/0590; GA AV ČR KSK6005114 Institutional research plan: CEZ:AV0Z60050516 Keywords : PVA * demography * model Subject RIV: EF - Botanics Impact factor: 4.594, year: 2005

  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. DEMOGRAPHIC CHALLENGES AND STAFF MOVEMENTS MODELING IN BUSINESS ORGANIZATIONS

    Directory of Open Access Journals (Sweden)

    Vladimir I. Kuznetsov

    2013-01-01

    Full Text Available In recent years a special attention is given to various aspects and problems of development of business and steady social and economic growth of modern Russia. In this context, a big scientific and practical interest is the all-round analysis of various barriers arising on a way of this process. A significant role belongs to specific threats of formation and modeling movement of the personnel in enterprises.

  11. 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

  12. 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

  13. Demographic Changes and Real Estate Values. A Quantitative Model for Analyzing the Urban-Rural Linkages

    Directory of Open Access Journals (Sweden)

    Massimiliano Bencardino

    2017-03-01

    Full Text Available Vast metropolitan areas include both urban areas and rural outskirts. Between these areas, there are strong links to the point which they cannot be examined separately. There is a contemporary presence of residential function and working activity in the rural outskirts, as well as in the typical sector of agriculture. Therefore, the production of goods and services for the city requires a combined analysis, due to the large territory which it has to consider. The evolution of the population of such a large territory can be studied in great detail, with reference to the single census area and with the use of Geographic Information Systems (GIS. This means that such a demographic development produces an effect on the values of the urban real estate. This work demonstrates the existing interconnections between urban areas and rural outskirts. Data collection on trends of the population living in the Naples metropolitan area and the house prices associated with this area, and the post spatial processing of such data, allows for the establishment of thematic maps according to which a model capable of interpreting the population development is defined. A study of the statistical correlations shows the consequences that the population dynamics produce for property prices. In addition, the diachronic analysis of the sales prices of residential buildings demonstrates that economic functions, exclusive of certain urban or rural territories, end up distributing and integrating.

  14. 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.

  15. 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.)

  16. Riser slugging - a mathematical model and the practical consequences

    Directory of Open Access Journals (Sweden)

    Svein I. Sagatun

    2005-04-01

    Full Text Available This article presents a novel approach to estimate severe riser slug build up time and consequently the slug period. The slug model is based on a simplified mechanical model. This information has subsequently been used to illustrate the effects of the traditional actions to prevent severe riser slugging. New field data from an offshore floating production platform and large scale experimental data are included. The experimental set up is described in detail. The estimate on the slug built up time provided by the simplified model matches data from the experiments, the full scale data and data in relevant references.

  17. 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)

  18. 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

  19. 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

  20. 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

  1. 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

  2. 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.

  3. Modeling Social Pressures Toward Political Instability in the United Kingdom after 1960: A Demographic Structural Analysis

    Directory of Open Access Journals (Sweden)

    Oscar Ortmans

    2017-12-01

    Full Text Available In the current paper, we investigate the predictive ability of Goldstone’s demographic structural model. In particular we seek to apply Turchin’s version of it to modeling the social pressures for political instability in the UK. It is then demonstrated that Turchin’s analysis of ‘demographic structural’ pressures in the US presents similar conditions that developed under neoliberalism during the same time periods in both countries. It is also demonstrated that the modeling of social pressures toward political instability in the UK and the USA performed by Peter Turchin and us can throw some light on the factors and patterns of the global sociopolitical destabilization wave of the 2010s. Thus, Goldstone’s demographic structural model might have some predictive potential not only at the national level, but also global scale.

  4. Reasoning about causes and consequences in Mulitlevel Flow Models

    DEFF Research Database (Denmark)

    Lind, Morten

    2012-01-01

    is the basis for implementation of automated model based reasoning functions whereas the more abstract specifica-tions provides generic process knowledge for formulation of reasoning strategies and for giving explanations. Reasoning strategies and explanations can be directly visualized in terms of the means......The purpose of the paper is to describe how multilevel flow models are used for reasoning about causes and consequences in complex dynamic processes. Reasoning in MFM models derives its power from representation of process knowledge on several levels of specification. The detailed specification......-end topology of the multilevel flow models and may be used for design of human machine interfaces supporting diagrammatic reasoning about spatial-temporal aspects of dynamic situations. The principles described in the paper have been used in the implementation of a model based reasoning system....

  5. Genomic Analysis of Demographic History and Ecological Niche Modeling in the Endangered Sumatran Rhinoceros Dicerorhinus sumatrensis.

    Science.gov (United States)

    Mays, Herman L; Hung, Chih-Ming; Shaner, Pei-Jen; Denvir, James; Justice, Megan; Yang, Shang-Fang; Roth, Terri L; Oehler, David A; Fan, Jun; Rekulapally, Swanthana; Primerano, Donald A

    2018-01-08

    The vertebrate extinction rate over the past century is approximately 22-100 times greater than background extinction rates [1], and large mammals are particularly at risk [2, 3]. Quaternary megafaunal extinctions have been attributed to climate change [4], overexploitation [5], or a combination of the two [6]. Rhinoceroses (Family: Rhinocerotidae) have a rich fossil history replete with iconic examples of climate-induced extinctions [7], but current pressures threaten to eliminate this group entirely. The Sumatran rhinoceros (Dicerorhinus sumatrensis) is among the most imperiled mammals on earth. The 2011 population was estimated at ≤216 wild individuals [8], and currently the species is extirpated, or nearly so, throughout the majority of its former range [8-12]. Understanding demographic history is important in placing current population status into a broader ecological and evolutionary context. Analysis of the Sumatran rhinoceros genome reveals extreme changes in effective population size throughout the Pleistocene. Population expansion during the early to middle Pleistocene was followed by decline. Ecological niche modeling indicated that changing climate most likely played a role in the decline of the Sumatran rhinoceros, as less suitable habitat on an emergent Sundaland corridor isolated Sumatran rhinoceros populations. By the end of the Pleistocene, the Sundaland corridor was submerged, and populations were fragmented and consequently reduced to low Holocene levels from which they would never recover. Past events denuded the Sumatran rhinoceros of genetic diversity through population decline, fragmentation, or some combination of the two and most likely made the species even more susceptible to later exploitation and habitat loss. VIDEO ABSTRACT. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  6. 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.

  7. Data-driven model for the assessment ofMycobacterium tuberculosistransmission in evolving demographic structures.

    Science.gov (United States)

    Arregui, Sergio; Iglesias, María José; Samper, Sofía; Marinova, Dessislava; Martin, Carlos; Sanz, Joaquín; Moreno, Yamir

    2018-03-21

    In the case of tuberculosis (TB), the capabilities of epidemic models to produce quantitatively robust forecasts are limited by multiple hindrances. Among these, understanding the complex relationship between disease epidemiology and populations' age structure has been highlighted as one of the most relevant. TB dynamics depends on age in multiple ways, some of which are traditionally simplified in the literature. That is the case of the heterogeneities in contact intensity among different age strata that are common to all airborne diseases, but still typically neglected in the TB case. Furthermore, while demographic structures of many countries are rapidly aging, demographic dynamics are pervasively ignored when modeling TB spreading. In this work, we present a TB transmission model that incorporates country-specific demographic prospects and empirical contact data around a data-driven description of TB dynamics. Using our model, we find that the inclusion of demographic dynamics is followed by an increase in the burden levels predicted for the next decades in the areas of the world that are most hit by the disease today. Similarly, we show that considering realistic patterns of contacts among individuals in different age strata reshapes the transmission patterns reproduced by the models, a result with potential implications for the design of age-focused epidemiological interventions. Copyright © 2018 the Author(s). Published by PNAS.

  8. Why do faultlines matter? A computational model of how strong demographic faultlines undermine team cohesion

    NARCIS (Netherlands)

    Flache, Andreas; Mas, Michael; Mäs, Michael

    Lau and Murnighan (LM) suggested that strong demographic faultlines threaten team cohesion and reduce consensus. However, it remains unclear which assumptions are exactly needed to derive faultline effects. We propose a formal computational model of the effects of faultlines that uses four

  9. 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...

  10. Experimental consequences of a horizontal gauge model for CP nonconservation

    International Nuclear Information System (INIS)

    Hou, W.; Soni, A.

    1985-01-01

    The experimental consequences of a model that links CP nonconservation with horizontal interactions and is based on the gauge group SU/sub l//sup W/(2) x SU/sub R//sup H/(2) x U/sup Y/ (1) are investigated. The magnitude of the observed CP nonconservation and that of the K/sub L/-K/sub S/ mass difference constrains the horizontal gauge boson masses (M/sub s/crR) such that 66 TeV> or approx. =M/sub s/crR>5 TeV. The model implies an extremely small value for Vertical Barepsilon'/epsilonVertical Bar. The branching ratio for K/sub L/→μe (K→πμe) could be greater than roughly-equal10 -10 (approx.10 -12 ). theta/sub QFD/ vanishes at the tree level. The contribution from the gauge sector, arising at two loops, is also discussed

  11. 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

  12. Modelling the lifetime economic consequences of glaucoma in France.

    Science.gov (United States)

    Philippe Nordmann, Jean; Lafuma, Antoine; Berdeaux, Gilles

    2009-03-01

    To estimate the lifetime economic consequences of glaucoma in France. A Markov model estimated the average discounted outcome and cost of glaucoma treatment over a patient's lifetime. Clinical states were defined as first- to fourth-line drugs, no treatment, laser therapy, surgery, blindness and death. After each failure (always after the fourth-line drug) patients could receive either laser treatment or surgery followed by no treatment, or a new treatment. A societal perspective was adopted. Sensitivity analyses were performed. Discounted medical costs were euro 7,322 for ocular hypertension treatment (OHT) and euro 8,488 for a glaucoma patient. Social costs of OHT and glaucoma patients exceeded medical costs. First-line use of the most effective drug would reduce medical and social costs. Societal willingness to pay for the vision benefit would equal the medical costs. Treatment initiated with the most effective drug is a cost saving strategy. Public health decisions in glaucoma treatment should take a broad economic view embracing the lifetime duration of the disease. There is still a place both within and outside the healthcare system for therapeutic innovations with important economic consequences that bring high added value to patients.

  13. Demographic model selection using random forests and the site frequency spectrum.

    Science.gov (United States)

    Smith, Megan L; Ruffley, Megan; Espíndola, Anahí; Tank, David C; Sullivan, Jack; Carstens, Bryan C

    2017-09-01

    Phylogeographic data sets have grown from tens to thousands of loci in recent years, but extant statistical methods do not take full advantage of these large data sets. For example, approximate Bayesian computation (ABC) is a commonly used method for the explicit comparison of alternate demographic histories, but it is limited by the "curse of dimensionality" and issues related to the simulation and summarization of data when applied to next-generation sequencing (NGS) data sets. We implement here several improvements to overcome these difficulties. We use a Random Forest (RF) classifier for model selection to circumvent the curse of dimensionality and apply a binned representation of the multidimensional site frequency spectrum (mSFS) to address issues related to the simulation and summarization of large SNP data sets. We evaluate the performance of these improvements using simulation and find low overall error rates (~7%). We then apply the approach to data from Haplotrema vancouverense, a land snail endemic to the Pacific Northwest of North America. Fifteen demographic models were compared, and our results support a model of recent dispersal from coastal to inland rainforests. Our results demonstrate that binning is an effective strategy for the construction of a mSFS and imply that the statistical power of RF when applied to demographic model selection is at least comparable to traditional ABC algorithms. Importantly, by combining these strategies, large sets of models with differing numbers of populations can be evaluated. © 2017 John Wiley & Sons Ltd.

  14. 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 albatrosses had

  15. Bayesian Analysis of Evolutionary Divergence with Genomic Data under Diverse Demographic Models.

    Science.gov (United States)

    Chung, Yujin; Hey, Jody

    2017-06-01

    We present a new Bayesian method for estimating demographic and phylogenetic history using population genomic data. Several key innovations are introduced that allow the study of diverse models within an Isolation-with-Migration framework. The new method implements a 2-step analysis, with an initial Markov chain Monte Carlo (MCMC) phase that samples simple coalescent trees, followed by the calculation of the joint posterior density for the parameters of a demographic model. In step 1, the MCMC sampling phase, the method uses a reduced state space, consisting of coalescent trees without migration paths, and a simple importance sampling distribution without the demography of interest. Once obtained, a single sample of trees can be used in step 2 to calculate the joint posterior density for model parameters under multiple diverse demographic models, without having to repeat MCMC runs. Because migration paths are not included in the state space of the MCMC phase, but rather are handled by analytic integration in step 2 of the analysis, the method is scalable to a large number of loci with excellent MCMC mixing properties. With an implementation of the new method in the computer program MIST, we demonstrate the method's accuracy, scalability, and other advantages using simulated data and DNA sequences of two common chimpanzee subspecies: Pan troglodytes (P. t.) troglodytes and P. t. verus. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. 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

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

    Science.gov (United States)

    Tatem, Andrew J; Adamo, Susana; Bharti, Nita; Burgert, Clara R; Castro, Marcia; Dorelien, Audrey; Fink, Gunter; Linard, Catherine; John, Mendelsohn; Montana, Livia; Montgomery, Mark R; Nelson, Andrew; Noor, Abdisalan M; Pindolia, Deepa; Yetman, Greg; Balk, Deborah

    2012-05-16

    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 spatial population datasets and

  18. How to get the timing right. A computational model of the effects of the timing of contacts on team cohesion in demographically diverse teams

    NARCIS (Netherlands)

    Flache, Andreas; Mäs, Michael

    Lau and Murnighan’s faultline theory explains negative effects of demographic diversity on team performance as consequence of strong demographic faultlines. If demographic differences between group members are correlated across various dimensions, the team is likely to show a “subgroup split” that

  19. 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.

  20. Using a multivariate model to assess the interactive effects of demographics and lifestyle on the hematological profile

    NARCIS (Netherlands)

    McArtor, Daniel B; Lin, Bochao D; Hottenga, Jouke-Jan; Boomsma, Dorret I; Willemsen, Gonneke; Lubke, Gitta H

    2017-01-01

    AIM: To assess the extent to which a multivariate approach to modeling interrelated hematological indices provides more informative results than the traditional approach of modeling each index separately. MATERIALS & METHODS: The effects of demographics and lifestyle on ten hematological indices

  1. Effects of climate change on an emperor penguin population: analysis of coupled demographic and climate models.

    Science.gov (United States)

    Jenouvrier, Stéphanie; Holland, Marika; Stroeve, Julienne; Barbraud, Christophe; Weimerskirch, Henri; Serreze, Mark; Caswell, Hal

    2012-09-01

    Sea ice conditions in the Antarctic affect the life cycle of the emperor penguin (Aptenodytes forsteri). We present a population projection for the emperor penguin population of Terre Adélie, Antarctica, by linking demographic models (stage-structured, seasonal, nonlinear, two-sex matrix population models) to sea ice forecasts from an ensemble of IPCC climate models. Based on maximum likelihood capture-mark-recapture analysis, we find that seasonal sea ice concentration anomalies (SICa ) affect adult survival and breeding success. Demographic models show that both deterministic and stochastic population growth rates are maximized at intermediate values of annual SICa , because neither the complete absence of sea ice, nor heavy and persistent sea ice, would provide satisfactory conditions for the emperor penguin. We show that under some conditions the stochastic growth rate is positively affected by the variance in SICa . We identify an ensemble of five general circulation climate models whose output closely matches the historical record of sea ice concentration in Terre Adélie. The output of this ensemble is used to produce stochastic forecasts of SICa , which in turn drive the population model. Uncertainty is included by incorporating multiple climate models and by a parametric bootstrap procedure that includes parameter uncertainty due to both model selection and estimation error. The median of these simulations predicts a decline of the Terre Adélie emperor penguin population of 81% by the year 2100. We find a 43% chance of an even greater decline, of 90% or more. The uncertainty in population projections reflects large differences among climate models in their forecasts of future sea ice conditions. One such model predicts population increases over much of the century, but overall, the ensemble of models predicts that population declines are far more likely than population increases. We conclude that climate change is a significant risk for the emperor

  2. 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)

  3. 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.

  4. 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

  5. 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.

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

    Science.gov (United States)

    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. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. 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)

  8. 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

  9. Global dynamics of a network-based SIQRS epidemic model with demographics and vaccination

    Science.gov (United States)

    Huang, Shouying; Chen, Fengde; Chen, Lijuan

    2017-02-01

    This paper investigates a new SIQRS epidemic model with demographics and vaccination on complex heterogeneous networks. We analytically derive the basic reproduction number R0, which determines not only the existence of endemic equilibrium but also the global dynamics of the model. The permanence of the disease and the globally asymptotical stability of disease-free equilibrium are proved in detail. By using a monotone iterative technique, we show that the unique endemic equilibrium is globally attractive under certain conditions. Our results really improve and enrich the results in Li et al (2014) [14]. Interestingly, the basic reproduction number R0 bears no relation to the degree-dependent birth, but our simulations indicate that the degree-dependent birth does affect the epidemic dynamics. Furthermore, we find that quarantine plays a more active role than vaccination in controlling the disease.

  10. Beyond R 0: Demographic Models for Variability of Lifetime Reproductive Output

    Science.gov (United States)

    Caswell, Hal

    2011-01-01

    The net reproductive rate measures the expected lifetime reproductive output of an individual, and plays an important role in demography, ecology, evolution, and epidemiology. Well-established methods exist to calculate it from age- or stage-classified demographic data. As an expectation, provides no information on variability; empirical measurements of lifetime reproduction universally show high levels of variability, and often positive skewness among individuals. This is often interpreted as evidence of heterogeneity, and thus of an opportunity for natural selection. However, variability provides evidence of heterogeneity only if it exceeds the level of variability to be expected in a cohort of identical individuals all experiencing the same vital rates. Such comparisons require a way to calculate the statistics of lifetime reproduction from demographic data. Here, a new approach is presented, using the theory of Markov chains with rewards, obtaining all the moments of the distribution of lifetime reproduction. The approach applies to age- or stage-classified models, to constant, periodic, or stochastic environments, and to any kind of reproductive schedule. As examples, I analyze data from six empirical studies, of a variety of animal and plant taxa (nematodes, polychaetes, humans, and several species of perennial plants). PMID:21738586

  11. 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

  12. 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

  13. 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

  14. 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.

  15. Improving the accuracy of demographic and molecular clock model comparison while accommodating phylogenetic uncertainty.

    Science.gov (United States)

    Baele, Guy; Lemey, Philippe; Bedford, Trevor; Rambaut, Andrew; Suchard, Marc A; Alekseyenko, Alexander V

    2012-09-01

    Recent developments in marginal likelihood estimation for model selection in the field of Bayesian phylogenetics and molecular evolution have emphasized the poor performance of the harmonic mean estimator (HME). Although these studies have shown the merits of new approaches applied to standard normally distributed examples and small real-world data sets, not much is currently known concerning the performance and computational issues of these methods when fitting complex evolutionary and population genetic models to empirical real-world data sets. Further, these approaches have not yet seen widespread application in the field due to the lack of implementations of these computationally demanding techniques in commonly used phylogenetic packages. We here investigate the performance of some of these new marginal likelihood estimators, specifically, path sampling (PS) and stepping-stone (SS) sampling for comparing models of demographic change and relaxed molecular clocks, using synthetic data and real-world examples for which unexpected inferences were made using the HME. Given the drastically increased computational demands of PS and SS sampling, we also investigate a posterior simulation-based analogue of Akaike's information criterion (AIC) through Markov chain Monte Carlo (MCMC), a model comparison approach that shares with the HME the appealing feature of having a low computational overhead over the original MCMC analysis. We confirm that the HME systematically overestimates the marginal likelihood and fails to yield reliable model classification and show that the AICM performs better and may be a useful initial evaluation of model choice but that it is also, to a lesser degree, unreliable. We show that PS and SS sampling substantially outperform these estimators and adjust the conclusions made concerning previous analyses for the three real-world data sets that we reanalyzed. The methods used in this article are now available in BEAST, a powerful user

  16. Positive consequences of intrinsically rewarding work: A model to ...

    African Journals Online (AJOL)

    This study sought to empirically test a theoretical model outlining the relationships between intrinsic rewards, intrinsic motivation, work engagement and intention to quit, in an attempt to empirically assess whether intrinsic rewards result in improved levels of motivation, engagement and retention. Using a sample of 587 ...

  17. 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.

  18. 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; Stroeve, Julienne; Weimerskirch, Henri

    2009-02-10

    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 approximately 6,000 to approximately 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.

  19. 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.

  20. 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.

  1. Consequence of reputation in the Sznajd consensus model

    Energy Technology Data Exchange (ETDEWEB)

    Crokidakis, Nuno, E-mail: nuno@if.uff.b [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.

  2. Modelling the process of falling behind and its psychophysiological consequences.

    Science.gov (United States)

    Venhorst, Andreas; Micklewright, Dominic; Noakes, Timothy D

    2017-10-19

    A preceding article investigated the psychophysiological responses to falling behind a performance matched opponent. The following temporally linked cause-effect relationships were hypothesised: falling behind precedes deterioration in valence, deterioration in valence precedes development of an action crisis, experience of an action crisis precedes psychoneuroendocrinological distress response and non-adaptive distress response reduces conduciveness to high performance, thereby preceding performance decrement. In this article, we applied structural equation modelling to test the extent to which the observed data fit the hypothesised cause-effect relationships. A five-step procedure was applied to model the interrelationships between the major study variables in the hypothesised temporal order. Significant linear relationships were found between all hypothesised predictor and outcome variable pairs (pchange in valence was a significant mediator (p=0.011) as it explained 35% of the relationship between falling behind and action crisis. All hypothesised cause-effect relationships continued to be significant after controlling for performance, descriptor, training and perceived strain variables. The observed data fitted the hypothesised structural model well with excellent model fit indices throughout. We applied, tested and confirmed the hypothesised debilitative psychophysiological processes that unfold in response to falling behind a performance matched opponent. The main findings were: deterioration in valence mediated the relationship between falling behind and action crisis, the mindset shift associated with an action crisis predicted increased blood cortisol concentrations and non-adaptive blood cortisol concentrations predicted performance decrement. The findings point towards the crucial role of affective and cognitive modifiers in centrally regulated and goal-directed exercise behaviour. © Article author(s) (or their employer(s) unless otherwise stated in

  3. 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.

  4. Complementarity and conflict among population and other policies: specifying an economic-demographic model for a developing country.

    Science.gov (United States)

    Mariano, R S

    1993-01-01

    The demographic and economic model illustrates the links between demographic and socioeconomic factors and government policy for developing countries. The operating model attempts to balance practical realities with manageability. The Philippines was used to show how the model operates. Demographic planners should be involved in the early development stages of policy development. The sociodemographic and economic framework by Orbeta has identified population outcomes affecting the economic system and the population system (fertility, mortality, and migration), both of which affect economic outcomes. The Economic system is comprised of consumption, investments, fiscal budgets, money supply, international trade and finance, labor use, and land use, which interact with private and public expenditures, employment, educational status, health status, housing, and environmental quality. A two way interrelationship exists between the demographic and socioeconomic variables. The model assumes that development outcomes affect the number, composition, and location of individuals. The application of the model to the Philippines used ordinary least squares and two stage least squares for estimation pertaining to the real sector, the fiscal sector, the financial sector, the external sector, and the price-wage-employment sector. The model combines classical, Keynesian, structuralist, and monetarist approaches. Domestic production is composed of agriculture, industry, and services in supply and demand equations. Expenditures are composed of personal consumption, gross domestic capital formation, exports, imports, and government expenditures. Further details of the model are described by Klein et al. and Mariano and Constantino.

  5. Niche variability and its consequences for species distribution modeling.

    Science.gov (United States)

    Michel, Matt J; Knouft, Jason H

    2012-01-01

    When species distribution models (SDMs) are used to predict how a species will respond to environmental change, an important assumption is that the environmental niche of the species is conserved over evolutionary time-scales. Empirical studies conducted at ecological time-scales, however, demonstrate that the niche of some species can vary in response to environmental change. We use habitat and locality data of five species of stream fishes collected across seasons to examine the effects of niche variability on the accuracy of projections from Maxent, a popular SDM. We then compare these predictions to those from an alternate method of creating SDM projections in which a transformation of the environmental data to similar scales is applied. The niche of each species varied to some degree in response to seasonal variation in environmental variables, with most species shifting habitat use in response to changes in canopy cover or flow rate. SDMs constructed from the original environmental data accurately predicted the occurrences of one species across all seasons and a subset of seasons for two other species. A similar result was found for SDMs constructed from the transformed environmental data. However, the transformed SDMs produced better models in ten of the 14 total SDMs, as judged by ratios of mean probability values at known presences to mean probability values at all other locations. Niche variability should be an important consideration when using SDMs to predict future distributions of species because of its prevalence among natural populations. The framework we present here may potentially improve these predictions by accounting for such variability.

  6. Niche variability and its consequences for species distribution modeling.

    Directory of Open Access Journals (Sweden)

    Matt J Michel

    Full Text Available When species distribution models (SDMs are used to predict how a species will respond to environmental change, an important assumption is that the environmental niche of the species is conserved over evolutionary time-scales. Empirical studies conducted at ecological time-scales, however, demonstrate that the niche of some species can vary in response to environmental change. We use habitat and locality data of five species of stream fishes collected across seasons to examine the effects of niche variability on the accuracy of projections from Maxent, a popular SDM. We then compare these predictions to those from an alternate method of creating SDM projections in which a transformation of the environmental data to similar scales is applied. The niche of each species varied to some degree in response to seasonal variation in environmental variables, with most species shifting habitat use in response to changes in canopy cover or flow rate. SDMs constructed from the original environmental data accurately predicted the occurrences of one species across all seasons and a subset of seasons for two other species. A similar result was found for SDMs constructed from the transformed environmental data. However, the transformed SDMs produced better models in ten of the 14 total SDMs, as judged by ratios of mean probability values at known presences to mean probability values at all other locations. Niche variability should be an important consideration when using SDMs to predict future distributions of species because of its prevalence among natural populations. The framework we present here may potentially improve these predictions by accounting for such variability.

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

    Science.gov (United States)

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

    2007-03-01

    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.

  8. 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

  9. Integrated modeling of communities: parasitism, competition, and demographic synchrony in sympatric ducks.

    Science.gov (United States)

    Péron, Guillaume; Koons, David N

    2012-11-01

    Functionally similar species often co-occur within an ecosystem, and they can compete for or facilitate each other's access to resources. The coupled dynamics of such species play an important role in shaping biodiversity and an ecosystem's resilience to perturbations. Here we study two congeneric North American ducks: Redhead Aythya americana and Canvasback A. vaselineria. Both are largely sympatric during the breeding season, and in addition to competition, facultative parasitic egg-laying can lead to interspecific density dependence. Using multi-population integrated models, we combined capture-recovery data, population surveys, and age ratio data in order to simultaneously estimate the mechanistic drivers of fecundity, survival, and population dynamics for both species. Canvasback numbers positively affected Redhead fecundity, whereas Redhead numbers negatively affected Canvasback fecundity, as expected due to parasitism. This interaction was modulated by wetland habitat availability in a way that matched the observation that Redhead hens parasitize Canvasback nests under all conditions but exhibit typical nesting behavior more frequently during years with numerous ponds. Once these effects of density and habitat were statistically controlled for, we found high levels of interspecific synchrony in both fecundity and survival (respectively, 75% and 49% of remaining variation). Thus, both neutral and non-neutral mechanisms affected the dynamics of these functionally similar species. In this and other systems, our method can be used to test hypotheses about species coexistence and to gain insights into the demographic drivers of community dynamics.

  10. 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

  11. 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).

  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. An agro-town bias? Re-examining the micro-demographic model for Southern Italy in the eighteenth century

    NARCIS (Netherlands)

    Curtis, Daniel

    2015-01-01

    Over the past 25 years, there has been an orthodox view established that 18thcentury Southern Italy had a distinctive micro-demographic model based around a number of facets, 3 key ones being a proliferation of neo-local small nuclear households, an exceptionally low average age of first marriage

  14. Uncovering patterns of spring migration in the monarch butterfly using stable isotopes and demographic models

    Science.gov (United States)

    Norris, R.; Miller, N.; Wassenaar, L.; Hobson, K.

    2010-12-01

    Each spring, millions of monarch butterflies (Danaus plexippus) migrate up to 3000 km from central Mexico to re-colonize eastern North America. However, despite centuries of research, the patterns of re-colonization are not well understood. We combined stable-hydrogen (δD) and -carbon (δ13C) isotope measurements with demographic models to test (1) whether individuals sampled in the northern part of the breeding range in the Great Lakes originate directly from Mexico or are second generation individuals born in the southern US and (2) to estimate whether populations on the eastern seaboard migrate longitudinally over the Appalachians or originate directly from the Gulf Coast. In the Great Lakes, we found that the majority of individuals were second-generation monarchs born in the Gulf Coast and Central regions of the US. However, 25% individuals originated directly from Mexico and we estimated that these individuals produced the majority of offspring born in the Great Lakes region during June. On the eastern seaboard, we found the majority of monarchs (88%) originated in the mid-west and Great Lakes regions, providing the first direct evidence that second generation monarchs born in June complete a (trans-) longitudinal migration across the Appalachian mountains. The remaining individuals (12%) originated from parents that migrated directly from the Gulf coast during early spring. Our results demonstrate how stable isotopes, when combined with ecological data, can provide insights into patterns of connectivity in migratory insects that have been impossible to test using conventional techniques. The migration patterns presented here have important implications for predicting future changes in population size and for developing effective conservation plans for this species.

  15. 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.

  16. 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

  17. Population growth and income growth during the demographic transition: does a Malthusian model help explain their relationship?

    Science.gov (United States)

    Blanchet, D

    1990-01-01

    This paper examines the potential links between growth of income/head and population growth during demographic transition. In so doing, both malthusian and neo-Boserupian views are considered with a view to determining which of the 2 paradigms is most useful in explaining the current situation in developing countries. The relationship between demographic and economic progress in the Malthusian system when it is initiated by an exogenous technical progress is discussed. Attention is also called to the recent disappearance of a negative correlation between economic and demographic growth. Finally, the neo-Boseupian model is compared to the Malthusian view, and implications of the analysis as they relate to the desirability of population policies are presented.

  18. 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)

  19. Spatially explicit models of dynamic histories: examination of the genetic consequences of Pleistocene glaciation and recent climate change on the American Pika.

    Science.gov (United States)

    Brown, Jason L; Knowles, L Lacey

    2012-08-01

    A central goal of phylogeography is to identify and characterize the processes underlying divergence. One of the biggest impediments currently faced is how to capture the spatiotemporal dynamic under which a species evolved. Here, we described an approach that couples species distribution models (SDMs), demographic and genetic models in a spatiotemporally explicit manner. Analyses of American Pika (Ochotona princeps) from the sky islands of the central Rocky Mountains of North America are used to provide insights into key questions about integrative approaches in landscape genetics, population genetics and phylogeography. This includes (i) general issues surrounding the conversion of time-specific SDMs into simple continuous, dynamic landscapes from past to current, (ii) the utility of SDMs to inform demographic models with deme-specific carrying capacities and migration potentials as well as (iii) the contribution of the temporal dynamic of colonization history in shaping genetic patterns of contemporary populations. Our results support that the inclusion of a spatiotemporal dynamic is an important factor when studying the impact of distributional shifts on patterns of genetic data. Our results also demonstrate the utility of SDMs to generate species-specific predictions about patterns of genetic variation that account for varying degrees of habitat specialization and life history characteristics of taxa. Nevertheless, the results highlight some key issues when converting SDMs for use in demographic models. Because the transformations have direct effects on the genetic consequence of population expansion by prescribing how habitat heterogeneity and spatiotemporal variation is related to the species-specific demographic model, it is important to consider alternative transformations when studying the genetic consequences of distributional shifts. © 2012 Blackwell Publishing Ltd.

  20. 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.

  1. 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.

  2. 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.

  3. Consequence modeling of fire on Methane storage tanks in a gas refinery

    Directory of Open Access Journals (Sweden)

    Sara Shahedi ali abadi

    2016-06-01

    Full Text Available Introduction: using fossil fuels, some hazards such as explosion and fire are probable. This study was aimed to consequence modeling of fire on Methane storage tanks in a gas refinery using analyzing the risk, and modeling and evaluating the related consequences. Method: Hazard analysis by PHA was used to choosing the worst-case scenario. Then, causes of the scenario were determined by FTA. After that, consequence modeling by the PHAST software was applied for the consequence analysis. Results: Based on some criteria, the fire of methane gas tank (V-100 was selected as the worst-case scenario at the refinery. The qualitative fault tree showed three factors including mechanical, process, and human failures contribute in gas leakage. The leakage size and weather conditions were effective on the distance of radiation. Using consequence modeling, thermal radiation was considered as the major outcome of the incident. Finally, for outcome evaluating, probit equations were used to quantify losses and the percentage of fatalities due to the methane gas leakage and fire occurrence. The maximum number of fatalities caused by fire was obtained 23 persons. Conclusions: In conclusion, the methane gas vessel in the refinery can be considered as the main center of hazard, therefore the implementation of the safety rules, eliminating mechanical failures, personal protection and education, and Effective measures to prevent and fighting of fire are proposed for decreasing the probable losses and fatalities.

  4. 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)

  5. 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.

  6. The IWG (Interagency Working Group) model for the heterosexual spread of HIV and the demographic impact of the AIDS epidemic

    Energy Technology Data Exchange (ETDEWEB)

    Stanley, E.A. (Los Alamos National Lab., NM (USA)); Seitz, S.T. (Illinois Univ., Urbana, IL (USA)); Way, P.O.; Johnson, P.D. (Bureau of the Census, Washington, DC (USA)); Curry, T.F. (Air Force Academy, CO (USA))

    1990-01-01

    This paper presents the State Department's Interagency Working Group (IWG) model for the spread of HIV. The model is fully operational for Pattern 2 (heterosexual blood transmission) and Pattern 3 (heterosexual, homosexual, and IV drug transmission) countries. This model was developed for various uses, including technical research, policy analysis, and support for decision making. Research uses include studying patterns of HIV spread, assessing the relative effect of different processes on the spread of HIV, examining the demographic impact of HIV infections, and comparing the potential impact of behavioral versus medical intervention strategies. The model will be used in workshops where policy makers and health officials can do hands-on scenario analyses, gain qualitative insights into the possible long-term-epidemiological and demographic impact of HIV, gauge the uncertainties in predictions for the future, and study the impact of HIV, gauge the uncertainties in predictions for the future, and study the impact that intervention strategies are likely to have. The computational model uses a deterministic system of differential equations and runs on a 286- or a 386-based IBM-compatible machine under Microsoft Windows. The program requires an input ASCII (text) file to run; all parameters used by the model are input through this file and, therefore, are user-accessible. The software is user-friendly, mouse-driven, and allows for interactive manipulation of input data and visualization and processing of model outputs. 15 refs., 13 figs., 1 tab.

  7. 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......Deaths from cancer in Denmark from 1943-1978 were extracted from the Danish National Death Register at the Danish Institute for Clinical Epidemiology. This paper illustrates the relationship between demographic factors and mortality from a large group of cancers, which increases progressively from...

  8. Associations of demographic variables and the Health Belief Model constructs with Pap smear screening among urban women in Botswana

    Directory of Open Access Journals (Sweden)

    McFarl

    2013-10-01

    Full Text Available Ditsapelo M McFarland College of Nursing and Public Health, Adelphi University, Garden City, NY, USA Purpose: Papanicolaou (Pap smear services are available in most urban areas in Botswana. Yet most women in such areas do not screen regularly for cancer of the cervix. The purpose of this article is to present findings on the associations of demographic variables and Health Belief Model constructs with Pap smear screening among urban women in Botswana. Sample and methods: The study included a convenience sample of 353 asymptomatic women aged 30 years and older who were living in Gaborone, Botswana. Data were collected using a demographic questionnaire and items of the Health Belief Model. Data analysis included descriptive statistics for demographic variables and bivariate and ordinal (logit regression to determine the associations of demographic variables. Results: Having health insurance and having a regular health care provider were significant predictors of whether or not women had a Pap smear. Women with health insurance were more likely to have had a Pap smear test than women without health insurance (91% vs 36%. Similarly, women who had a regular health care provider were more likely to have had a Pap smear test than women without a regular health care provider (94% vs 42%. Major barriers to screening included what was described as "laziness" for women who had ever had a Pap smear (57% and limited information about Pap smear screening for women who had never had a Pap smear (44%. Conclusion: There is a need for more information about the importance of the Pap smear test and for increased access to screening services in Botswana. Keywords: cervical, screening, barriers, access, beliefs

  9. Socio-demographics, spirituality, and quality of life among community-dwelling and institutionalized older adults: A structural equation model.

    Science.gov (United States)

    Soriano, Christian Albert F; Sarmiento, Winona D; Songco, Francis Justin G; Macindo, John Rey B; Conde, Alita R

    2016-01-01

    The increasing life expectancy of the population prompts an array of health conditions that impair an older adults' quality of life (QoL). Although demographics and spirituality have been associated with QoL, limited literature elucidated the exact mechanisms of their interactions, especially in a culturally-diverse country like Philippines. Hence, this study determined the relationship among socio-demographics, spirituality, and QoL of Filipino older adults in a community and institutional setting. A predictive-correlational study among 200 randomly-selected community-dwelling and institutionalized older adults was conducted, with a 99% power and a medium effect size. Data were collected using a three-part questionnaire from September to November 2015. The questionnaire was composed of the robotfoto, Spirituality Assessment Scale, and modified Older People's Quality of Life which assessed socio-demographics, spirituality, and QoL. Analysis showed that institutionalization in a nursing home positively and negatively affected spirituality and QoL, generating an acceptable model (χ(2)/df=2.12, RMSEA=0.08, and CFI=0.95). The negative direct effect of institutionalization on social relationship, leisure, & social activities QoL (β=-0.42, pspirituality and QoL dimensions. The development of a structural model illustrating the interrelationship of socio-demographics, spirituality, and QoL helps healthcare professionals in predicting facets of spirituality and QoL that can be compromised by living in a nursing home. This understanding provides impetus in evaluating and refining geriatric healthcare programs, policies, and protocols to render individualized, holistic care in a socially-cohesive environment among older adults. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  10. Associations of demographic variables and the Health Belief Model constructs with Pap smear screening among urban women in Botswana

    Science.gov (United States)

    McFarland, Ditsapelo M

    2013-01-01

    Purpose Papanicolaou (Pap) smear services are available in most urban areas in Botswana. Yet most women in such areas do not screen regularly for cancer of the cervix. The purpose of this article is to present findings on the associations of demographic variables and Health Belief Model constructs with Pap smear screening among urban women in Botswana. Sample and methods The study included a convenience sample of 353 asymptomatic women aged 30 years and older who were living in Gaborone, Botswana. Data were collected using a demographic questionnaire and items of the Health Belief Model. Data analysis included descriptive statistics for demographic variables and bivariate and ordinal (logit) regression to determine the associations of demographic variables. Results Having health insurance and having a regular health care provider were significant predictors of whether or not women had a Pap smear. Women with health insurance were more likely to have had a Pap smear test than women without health insurance (91% vs 36%). Similarly, women who had a regular health care provider were more likely to have had a Pap smear test than women without a regular health care provider (94% vs 42%). Major barriers to screening included what was described as “laziness” for women who had ever had a Pap smear (57%) and limited information about Pap smear screening for women who had never had a Pap smear (44%). Conclusion There is a need for more information about the importance of the Pap smear test and for increased access to screening services in Botswana. PMID:24179380

  11. 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...

  12. 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

  13. 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

  14. 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

  15. 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.

  16. 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.

  17. 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

  18. 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).

  19. Demographic model of the Swiss cattle population for the years 2009-2011 stratified by gender, age and production type.

    Directory of Open Access Journals (Sweden)

    Sara Schärrer

    Full Text Available Demographic composition and dynamics of animal and human populations are important determinants for the transmission dynamics of infectious disease and for the effect of infectious disease or environmental disasters on productivity. In many circumstances, demographic data are not available or of poor quality. Since 1999 Switzerland has been recording cattle movements, births, deaths and slaughter in an animal movement database (AMD. The data present in the AMD offers the opportunity for analysing and understanding the dynamic of the Swiss cattle population. A dynamic population model can serve as a building block for future disease transmission models and help policy makers in developing strategies regarding animal health, animal welfare, livestock management and productivity. The Swiss cattle population was therefore modelled using a system of ordinary differential equations. The model was stratified by production type (dairy or beef, age and gender (male and female calves: 0-1 year, heifers and young bulls: 1-2 years, cows and bulls: older than 2 years. The simulation of the Swiss cattle population reflects the observed pattern accurately. Parameters were optimized on the basis of the goodness-of-fit (using the Powell algorithm. The fitted rates were compared with calculated rates from the AMD and differed only marginally. This gives confidence in the fitted rates of parameters that are not directly deductible from the AMD (e.g. the proportion of calves that are moved from the dairy system to fattening plants.

  20. Overview of the arthritis Cost Consequence Evaluation System (ACCES): a pharmacoeconomic model for celecoxib.

    Science.gov (United States)

    Pettitt, D; Goldstein, J L; McGuire, A; Schwartz, J S; Burke, T; Maniadakis, N

    2000-12-01

    Pharmacoeconomic analyses have become useful and essential tools for health care decision makers who increasingly require such analyses prior to placing a drug on a national, regional or hospital formulary. Previous health economic models of non-steroidal anti-inflammatory drugs (NSAIDs) have been restricted to evaluating a narrow range of agents within specific health care delivery systems using medical information derived from homogeneous clinical trial data. This paper summarizes the Arthritis Cost Consequence Evaluation System (ACCES)--a pharmacoeconomic model that has been developed to predict and evaluate the costs and consequences associated with the use of celecoxib in patients with arthritis, compared with other NSAIDs and NSAIDs plus gastroprotective agents. The advantage of this model is that it can be customized to reflect local practice patterns, resource utilization and costs, as well as provide context-specific health economic information to a variety of providers and/or decision makers.

  1. 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.)

  2. 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

  3. Geo-Demographic Risks in the Apuseni Mountains. Demographic Ageing

    OpenAIRE

    GABRIELA-ALINA MUREŞAN; CRISTIAN-NICOLAE BOŢAN

    2014-01-01

    The territorial system of the Apuseni Mountains can be considered a critical region from a geo-demographic viewpoint. This is due to two major geo-demographic risks that affect it at present, namely the massive migration, mainly of the young and adult population, and the severe decrease in birth rate, also as a consequence of migration. These two processes determine the main two geo-demographic risks within the Apuseni Mountains: on the one hand, depopulation and the geo-demographic decline o...

  4. demogR: A Package for the Construction and Analysis of Age-structured Demographic Models in R

    Directory of Open Access Journals (Sweden)

    James Holland Jones

    2007-08-01

    Full Text Available The analysis of matrix population models has become a fundamental tool in ecology, conservation biology, and life history theory. In this paper, I present demogR, a package for analyzing age-structured population models in R. The package includes tools for the construction and analysis of matrix population models. In addition to the standard analyses commonly used in evolutionary demography and conservation biology, demogR contains a variety of tools from classical demography. This includes the construction of period life tables, and the generation of model mortality and fertility schedules for human populations. The tools in demogR are generally applicable to age-structured populations but are particularly useful for analyzing problems in human ecology. I illustrate some of the capabilities of the package by doing an evolutionary demographic analysis of several human populations.

  5. 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

  6. Advances in global sensitivity analyses of demographic-based species distribution models to address uncertainties in dynamic landscapes

    Directory of Open Access Journals (Sweden)

    Ilona Naujokaitis-Lewis

    2016-07-01

    Full Text Available Developing a rigorous understanding of multiple global threats to species persistence requires the use of integrated modeling methods that capture processes which influence species distributions. Species distribution models (SDMs coupled with population dynamics models can incorporate relationships between changing environments and demographics and are increasingly used to quantify relative extinction risks associated with climate and land-use changes. Despite their appeal, uncertainties associated with complex models can undermine their usefulness for advancing predictive ecology and informing conservation management decisions. We developed a computationally-efficient and freely available tool (GRIP 2.0 that implements and automates a global sensitivity analysis of coupled SDM-population dynamics models for comparing the relative influence of demographic parameters and habitat attributes on predicted extinction risk. Advances over previous global sensitivity analyses include the ability to vary habitat suitability across gradients, as well as habitat amount and configuration of spatially-explicit suitability maps of real and simulated landscapes. Using GRIP 2.0, we carried out a multi-model global sensitivity analysis of a coupled SDM-population dynamics model of whitebark pine (Pinus albicaulis in Mount Rainier National Park as a case study and quantified the relative influence of input parameters and their interactions on model predictions. Our results differed from the one-at-time analyses used in the original study, and we found that the most influential parameters included the total amount of suitable habitat within the landscape, survival rates, and effects of a prevalent disease, white pine blister rust. Strong interactions between habitat amount and survival rates of older trees suggests the importance of habitat in mediating the negative influences of white pine blister rust. Our results underscore the importance of considering habitat

  7. 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.

  8. 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)

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

    NARCIS (Netherlands)

    J. van der Waal (Jeroen); S.B.L. Daenekindt (Stijn); W. de Koster (Willem)

    2017-01-01

    textabstractObjectives: 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,

  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. 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

  12. Systematic iteration between model and methodology: A proposed approach to evaluating unintended consequences.

    Science.gov (United States)

    Morell, Jonathan A

    2017-09-18

    This article argues that evaluators could better deal with unintended consequences if they improved their methods of systematically and methodically combining empirical data collection and model building over the life cycle of an evaluation. This process would be helpful because it can increase the timespan from when the need for a change in methodology is first suspected to the time when the new element of the methodology is operational. The article begins with an explanation of why logic models are so important in evaluation, and why the utility of models is limited if they are not continually revised based on empirical evaluation data. It sets the argument within the larger context of the value and limitations of models in the scientific enterprise. Following will be a discussion of various issues that are relevant to model development and revision. What is the relevance of complex system behavior for understanding predictable and unpredictable unintended consequences, and the methods needed to deal with them? How might understanding of unintended consequences be improved with an appreciation of generic patterns of change that are independent of any particular program or change effort? What are the social and organizational dynamics that make it rational and adaptive to design programs around single-outcome solutions to multi-dimensional problems? How does cognitive bias affect our ability to identify likely program outcomes? Why is it hard to discern change as a result of programs being embedded in multi-component, continually fluctuating, settings? The last part of the paper outlines a process for actualizing systematic iteration between model and methodology, and concludes with a set of research questions that speak to how the model/data process can be made efficient and effective. Copyright © 2017. Published by Elsevier Ltd.

  13. 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

  14. Investigating patient safety culture across a health system: multilevel modelling of differences associated with service types and staff demographics.

    Science.gov (United States)

    Gallego, Blanca; Westbrook, Mary T; Dunn, Adam G; Braithwaite, Jeffrey

    2012-08-01

    To use multilevel modelling to compare the patient safety cultures of types of services across a health system and to determine whether differences found can be accounted for by staffs' professions, organizational roles, ages and type of patient care provided. Application of a hierarchical two-level regression model. All services in the South Australian public health system. Approximately half of the health staff (n = 14 054) in the 46 organizations, classified into 18 types of service, which made up the South Australian public health system. Staff completed the Safety Attitudes Questionnaire. Attitudes regarding Teamwork Climate, Safety Climate, Job Satisfaction, Stress Recognition, Perception of Management and Working Conditions in participants' workplaces. All SAQ indices showed statistically significant although modest variations according to service type. However, most of these differences were not accounted for by the differences in the demographic composition of services' staff. Most favourable safety attitudes were found in the breast screening, primary/community health services, community nursing and metropolitan non-teaching hospitals. Poorer cultures were reported in the psychiatric hospital, mental health, metropolitan ambulance services and top-level teaching hospitals. Demographic differences in safety attitudes were observed; particularly, clinical, senior managerial, aged care and older staff held more favourable attitudes. Differences in staff attitudes have been demonstrated at a macro-level across the type of health services but for the most part, differences could not be explained by staffing composition.

  15. 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

  16. 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).

  17. 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

  18. 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)

  19. 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)

  20. The importance of multiphase and multicomponent modeling in consequence and risk analysis

    International Nuclear Information System (INIS)

    Johnson, David W.; Marx, Jeffrey D.

    2003-01-01

    The ability to accurately predict the consequences of a hazardous fluid release is dependent on three things: the knowledge of the modeler, the quality of the model that is used, and the quality of the input parameters. One of the most difficult problems in consequence modeling is the prediction of post-release multiphase behavior, especially when a multicomponent mixture is involved. Releases from gas/oil wells often fit this description. The wellstream will produce a light crude oil and a gas stream when flashed into a separator. If accidentally released to the atmosphere, the gas, aerosol, and liquid fractions rarely match the phase separations in the separator, or the expectations of the modeler. And, since the wellstream has a wide range of hydrocarbon components, the need to accurately predict the multicomponent behavior becomes more important. Over the years, modelers have used several 'rules of thumb' to provide the source term input parameters for modeling multiphase/multicomponent releases and subsequent dispersion. These modeling assumptions can lead to hazard predictions that are very different from reality. The biggest problem with rules of thumb is their inability to account for thermodynamics; thus, they cannot approximate the phase splits and composition changes that do occur. The aim of this paper is to improve the knowledge of the modeler by providing some insight into the selection of the proper input parameters for multiphase releases of multicomponent fluids. The application of a multiphase release model with multicomponent thermodynamics to a wellstream release is used to illustrate the importance of good modeling techniques

  1. 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".

  2. 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

  3. 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.

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

    NARCIS (Netherlands)

    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

  5. Toward a Common Structure in Demographic Educational Modeling and Simulation: A Complex Systems Approach

    Science.gov (United States)

    Guevara, Porfirio

    2014-01-01

    This article identifies elements and connections that seem to be relevant to explain persistent aggregate behavioral patterns in educational systems when using complex dynamical systems modeling and simulation approaches. Several studies have shown what factors are at play in educational fields, but confusion still remains about the underlying…

  6. 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…

  7. Demographic modelling of the HIV/AIDS epidemic on the Soweto ...

    African Journals Online (AJOL)

    28 - 52% of all deaths. The total popUlation will continue to increase in size, even in the high AIDS scenario, with the population growth rate ranging from 1.8% Oow AIDS scenario) to 1% (high AIDS scenario) by the year 2010. This modelling exercise has demonstrated the enonnous potential impact of timeous and effective ...

  8. 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.

  9. 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

  10. Estimating the possible transfrontier consequences of accidental releases: the MESOS model for long range atmospheric dispersal

    International Nuclear Information System (INIS)

    Apsimon, H.M.; Goddard, A.; Wrigley, J.

    1980-01-01

    In the framework of a contract with the CEA/EURATOM Association and with added support from the Commission of the European Communities, the MESOS model has been developed to treat the problems more realistically, using a database giving meteorological data across Europe at 3 hour intervals. By tracing the histories and dispersal of a large number of sequential short period releases through a wide variety of synoptic situations, and by considering a few selected nuclides, it is possible to derive statistics on the possible consequences of a variety of hypothetical accidental releases of different durations. In accordance with the aims of the METEO group of experts these statistics are produced in the form of probability distributions at various selected exposure points, giving the probability that the time integrated atmospheric concentration, dry deposition or wet deposition at the exposure point for a given release, exceeds a series of different values. In this paper the MESOS model is described briefly, and predictions of the model when applied to the WINDSCALE incident of 1957 compared with measurements of I-131 made at the time. Finally application of the model to a few selected sites in Europe is illustrated by the statistics derived for unit releases of different nuclides, for use in estimating accident consequences

  11. Comments on "Complementarity and Conflict among Population and Other Policies: Specifying an Economic-Demographic Model for a Developing Country".

    Science.gov (United States)

    Khan, A H

    1993-01-01

    The critique of Mariano's economic-demographic model of population and other policies for developing countries cites the value of such a detailed model for developing a family planning policy within the context of macroeconomic government policies. The model points out the impact on fertility of effective family planning policies and increased educational expenditures. Work force participation and reduced fertility is also affected by increased female educational levels, which in combination with increasing health expenditures for children reduces infant mortality as a means of further reducing fertility. Savings and investment increase with reduced fertility and reduce population growth. Per capital income increases with higher investment and lower population growth; the effect is to increase resource availability for improvements in health and education. Rural-urban migration must be balanced by policies in urban areas supporting industrial investment and policies in rural areas for increased educational and health expenditures. Changes in the structure of demand affect the structure of the economy, which in turn affects exports. The paper contributes to a model of simultaneous equations for estimating the linkages between demography and economics factors already known. The model combines the Chicago-Columbia model and the Pennsylvania model but ignores biological variables such as those identified by Behrman and Wolfe as women's health status, breast feeding, and nutritional level. International migration may be important for some countries such as the Philippines and Thailand. Extended families may be an important variable excluded from the model. Criticism is directed to the measure of rural-urban migration which does not separate out by age those migrating between countries. The assumption is that international migrants only come from urban areas. In Bangladesh the man-land ratio was found to be important. Changing definitions of literacy may impact on the

  12. Demographic and regional economic modeling using stochastic allocation in the City of Johannesburg

    CSIR Research Space (South Africa)

    Lamprecht, TJ

    2005-11-01

    Full Text Available (mostly qualitative) characteristics of an area that affect its desirability for real estate development, but on which data may not exist. This criterion would be stronger for office than for industrial development, for instance, as office development...). These variables are included in UrbanSim’s real estate development model. The role of accessibility in the real estate development decision is widely accepted, even though recent evidence suggests that accessibility plays a somewhat smaller role...

  13. Modeling consumers’ intention to continue buying online when controlled for socio-demographic variables

    OpenAIRE

    Claudia ICONARU

    2012-01-01

    For studying consumers’ intention to buy online, ECM-IT framework was employed. Consumers’ behavioral intention is a function of both consumers’ satisfaction with their decision to buy online goods and services and perceived usefulness of using the Internet in the buying process, while consumers’ confirmation of initial expectations has a direct effect on both satisfaction and perceived usefulness. While ECM-IT was validated in various online consumer behavior models, the effect of control va...

  14. Planning, demographics and Slovenia

    Directory of Open Access Journals (Sweden)

    Aleksander Jakoš

    2009-01-01

    Full Text Available In this article, the issue of demographics is presented as one of the most important factors in regard to the future development of Slovenia. We are still not fully aware of the consequences of the demographic development in the past, which has caused the current situation. The balance between the active and retired population is disturbed, as the percentage of retired persons is on the increase. This process will continue, because the number of retirements will increase in the future, mainly due to the demographic reasons. In regard to the current age the structure of the population in Slovenia, we can expect a huge and absolute increase in the number of elderly people and an even faster increase in the percentage of elderly people in the entire population. The number of retired persons will indirectly increase due to the longer life expectancy. In a demographic sense, the increase of elderly people means a significantly higher annual number of deaths and therefore a strong negative natural growth. This will be even more evident due to the significant decrease of the number of births in the last 30 years. This problem arises not only from low birth rates, but also due to the fact that the generations of women in their fertility period are less numerous.

  15. 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.

  16. Consequence modeling for nuclear weapons probabilistic cost/benefit analyses of safety retrofits

    Energy Technology Data Exchange (ETDEWEB)

    Harvey, T.F.; Peters, L.; Serduke, F.J.D.; Hall, C.; Stephens, D.R.

    1998-01-01

    The consequence models used in former studies of costs and benefits of enhanced safety retrofits are considered for (1) fuel fires; (2) non-nuclear detonations; and, (3) unintended nuclear detonations. Estimates of consequences were made using a representative accident location, i.e., an assumed mixed suburban-rural site. We have explicitly quantified land- use impacts and human-health effects (e.g. , prompt fatalities, prompt injuries, latent cancer fatalities, low- levels of radiation exposure, and clean-up areas). Uncertainty in the wind direction is quantified and used in a Monte Carlo calculation to estimate a range of results for a fuel fire with uncertain respirable amounts of released Pu. We define a nuclear source term and discuss damage levels of concern. Ranges of damages are estimated by quantifying health impacts and property damages. We discuss our dispersal and prompt effects models in some detail. The models used to loft the Pu and fission products and their particle sizes are emphasized.

  17. 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.

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

    DEFF Research Database (Denmark)

    Juel, K

    1983-01-01

    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...... of the female cancers, k was found to be independent of cohort and in the last 6 cases k was found to be a linear function of cohort. For 12 out of 14 cancer sites among males the ratio of mortality in the capital to mortality in the provinces was significantly greater than one.(ABSTRACT TRUNCATED AT 250 WORDS)...

  19. 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.

  20. Genet longevity and populatiln age structure of the clonal pioneer species Geum reptans based on demographic field data and projection matrix modelling

    OpenAIRE

    de Witte, Lucienne C.; Scherrer, Daniel; Stöcklin, Jürg

    2011-01-01

    Genet life span is a key demographic trait for understanding life history of plants. However, the longevity of clonal plants is hard to determine, especially when inter-ramet connections are short-lived and plants subsequently move independently of one another in space by means of an expansive growth strategy. In this study we estimated genet life span in the clonal pioneer species Geumreptans, living on glacier forelands, by using a projection matrix model based on demographic field data of ...

  1. 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

  2. Impact of demographic characteristics in pet ownership: modeling animal count according to owners income and age.

    Science.gov (United States)

    Martins, Camila Marinelli; Mohamed, Ahmed; Guimarães, Ana Marcia Sá; de Barros, Cristiane da Conceição; Pampuch, Raquel Dos Santos; Svoboda, Walfrido; Garcia, Rita de Cassia Maria; Ferreira, Fernando; Biondo, Alexander Welker

    2013-05-01

    Pet owner characteristics such as age, gender, income/social class, marital status, rural/urban residence and household type have been shown to be associated with the number of owned pets. However, few studies to date have attempted to evaluate these associations in Brazil. Accordingly, the aim of this study was to evaluate the association between age and income of owners and the number of owned dogs and cats in a Brazilian urban center. Pinhais, metropolitan area of Curitiba, Southern Brazil, the seventh largest city in Brazil, was chosen for this study. Questionnaires were administered door-to-door between January and February 2007 and data were analyzed by zero-inflated negative binomial (ZINB) models. A total of 13,555 of 30,380 (44.62%) households were interviewed. The majority (62.43%) of households reported having one or more dogs, with one or two dogs being the most common (29.97% and 19.71%, respectively). Cat ownership per household was much lower (P=0.001) than dog ownership, with 90% of the households reported having no owned cats. ZINB analyses indicated that income is not associated with the number of both dogs and cats among households that have pets. However, households from higher income categories were more likely to have dogs (but not cats) when compared to the lowest income category (Ppets. Certain age categories were significantly associated with the number of dogs or cats in households that have pets. In addition, most age categories were significantly associated with having dogs and/or cats (Ppets; higher income households were more likely to have dogs when compared to low-income households. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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)

  8. 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

  9. Misspecification in Latent Change Score Models: Consequences for Parameter Estimation, Model Evaluation, and Predicting Change.

    Science.gov (United States)

    Clark, D Angus; Nuttall, Amy K; Bowles, Ryan P

    2018-01-01

    Latent change score models (LCS) are conceptually powerful tools for analyzing longitudinal data (McArdle & Hamagami, 2001). However, applications of these models typically include constraints on key parameters over time. Although practically useful, strict invariance over time in these parameters is unlikely in real data. This study investigates the robustness of LCS when invariance over time is incorrectly imposed on key change-related parameters. Monte Carlo simulation methods were used to explore the impact of misspecification on parameter estimation, predicted trajectories of change, and model fit in the dual change score model, the foundational LCS. When constraints were incorrectly applied, several parameters, most notably the slope (i.e., constant change) factor mean and autoproportion coefficient, were severely and consistently biased, as were regression paths to the slope factor when external predictors of change were included. Standard fit indices indicated that the misspecified models fit well, partly because mean level trajectories over time were accurately captured. Loosening constraint improved the accuracy of parameter estimates, but estimates were more unstable, and models frequently failed to converge. Results suggest that potentially common sources of misspecification in LCS can produce distorted impressions of developmental processes, and that identifying and rectifying the situation is a challenge.

  10. 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

  11. 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

  12. DEMOGRAPHIC TRANSITION AND DEMOGRAPHIC PROBLEM IN BULGARIA

    Directory of Open Access Journals (Sweden)

    Krasimir Levkov

    2017-12-01

    Full Text Available The demographic problem is a topical issue for the Bulgarian society. It is the result of a long socio-economic process that began in the 1920s. The author agrees that the solution of the demographic problem depends both on the correct demographic policy of the state and on the conscious demographic behavior of each of its citizens.

  13. 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...

  14. 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

  15. 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

  16. Risk factors and a predictive model for under-five mortality in Nigeria: evidence from Nigeria demographic and health survey

    Directory of Open Access Journals (Sweden)

    Kayode Gbenga A

    2012-02-01

    Full Text Available Abstract Background Under-5 mortality is a major public health challenge in developing countries. It is essential to identify determinants of under-five mortality (U5M childhood mortality because these will assist in formulating appropriate health programmes and policies in order to meet the United Nations MDG goal. The objective of this study was to develop a predictive model and identify maternal, child, family and other risk factors associated U5M in Nigeria. Methods Population-based cross-sectional study which explored 2008 demographic and health survey of Nigeria (NDHS with multivariable logistic regression. Likelihood Ratio Test, Hosmer-Lemeshow Goodness-of-Fit and Variance Inflation Factor were used to check the fit of the model and the predictive power of the model was assessed with Receiver Operating Curve (ROC curve. Results This study yielded an excellent predictive model which revealed that the likelihood of U5M among the children of mothers that had their first marriage at age 20-24 years and ≥ 25 years declined by 20% and 30% respectively compared to children of those that married before the age of 15 years. Also, the following factors reduced odds of U5M: health seeking behaviour, breastfeeding children for > 18 months, use of contraception, small family size, having one wife, low birth order, normal birth weight, child spacing, living in urban areas, and good sanitation. Conclusions This study has revealed that maternal, child, family and other factors were important risk factors of U5M in Nigeria. This study has identified important risk factors that will assist in formulating policies that will improve child survival.

  17. 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...... reliable estimates of the effect of MPAs, and can thus be a valuable tool when deciding where to locate MPA...

  18. 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

  19. Some interesting consequences from Newton's modified expression of gravitational force in the vector model for gravitational field

    International Nuclear Information System (INIS)

    Vo Van On

    2009-01-01

    In this paper, based on the Vector model for gravitational field we show some interesting consequence from Newton's modified expression of gravitational force: dividing the space into regions around galaxies, maximal sire of stable galaxies. (author)

  20. 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.

  1. 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

  2. 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...

  3. 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

  4. 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

  5. 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

  6. 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.

  7. Demographic modelling with whole-genome data reveals parallel origin of similar Pundamilia cichlid species after hybridization.

    Science.gov (United States)

    Meier, Joana I; Sousa, Vitor C; Marques, David A; Selz, Oliver M; Wagner, Catherine E; Excoffier, Laurent; Seehausen, Ole

    2017-01-01

    Modes and mechanisms of speciation are best studied in young species pairs. In older taxa, it is increasingly difficult to distinguish what happened during speciation from what happened after speciation. Lake Victoria cichlids in the genus Pundamilia encompass a complex of young species and polymorphic populations. One Pundamilia species pair, P. pundamilia and P. nyererei, is particularly well suited to study speciation because sympatric population pairs occur with different levels of phenotypic differentiation and reproductive isolation at different rocky islands within the lake. Genetic distances between allopatric island populations of the same nominal species often exceed those between the sympatric species. It thus remained unresolved whether speciation into P. nyererei and P. pundamilia occurred once, followed by geographical range expansion and interspecific gene flow in local sympatry, or if the species pair arose repeatedly by parallel speciation. Here, we use genomic data and demographic modelling to test these alternative evolutionary scenarios. We demonstrate that gene flow plays a strong role in shaping the observed patterns of genetic similarity, including both gene flow between sympatric species and gene flow between allopatric populations, as well as recent and early gene flow. The best supported model for the origin of P. pundamilia and P. nyererei population pairs at two different islands is one where speciation happened twice, whereby the second speciation event follows shortly after introgression from an allopatric P. nyererei population that arose earlier. Our findings support the hypothesis that very similar species may arise repeatedly, potentially facilitated by introgressed genetic variation. © 2016 John Wiley & Sons Ltd.

  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 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

  10. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Helton, J.C. [Arizona State Univ., Tempe, AZ (United States); Johnson, J.D.; Rollstin, J.A. [GRAM, Inc., Albuquerque, NM (United States); Shiver, A.W.; Sprung, J.L. [Sandia National Labs., Albuquerque, NM (United States)

    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.

  12. 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

  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. College Students' Drinking and Posting About Alcohol: Forwarding a Model of Motivations, Behaviors, and Consequences.

    Science.gov (United States)

    Thompson, Charee M; Romo, Lynsey K

    2016-06-01

    College drinking continues to remain a public health problem that has been exacerbated by alcohol-related posts on social networking sites (SNSs). Although existing research has linked alcohol consumption, alcohol posts, and adverse consequences to one another, comprehensive explanations for these associations have been largely unexplored. Thus, we reasoned that students' personal motivations (i.e., espousing an alcohol identity, needing entertainment, and adhering to social norms) influence their behaviors (i.e., alcohol consumption and alcohol-related posting on SNSs), which can lead to alcohol problems. Using structural equation modeling, we analyzed data from 364 undergraduate students and found general support for our model. In particular, espousing an alcohol identity predicted alcohol consumption and alcohol-related SNS posting, needing entertainment predicted alcohol consumption but not alcohol-related SNS posting, and adhering to social norms predicted alcohol-related SNS posting but not alcohol consumption. In turn, alcohol consumption and alcohol-related SNS posting predicted alcohol problems. It is surprising that alcohol-related SNS posting was a stronger predictor of alcohol problems than alcohol consumption. We discuss the findings within their applied applications for college student health.

  15. 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.

  16. Quaternary range and demographic expansion of Liolaemus darwinii (Squamata: Liolaemidae) in the Monte Desert of Central Argentina using Bayesian phylogeography and ecological niche modelling.

    Science.gov (United States)

    Camargo, Arley; Werneck, Fernanda P; Morando, Mariana; Sites, Jack W; Avila, Luciano J

    2013-08-01

    Until recently, most phylogeographic approaches have been unable to distinguish between demographic and range expansion processes, making it difficult to test for the possibility of range expansion without population growth and vice versa. In this study, we applied a Bayesian phylogeographic approach to reconstruct both demographic and range expansion in the lizard Liolaemus darwinii of the Monte Desert in Central Argentina, during the Late Quaternary. Based on analysis of 14 anonymous nuclear loci and the cytochrome b mitochondrial DNA gene, we detected signals of demographic expansion starting at ~55 ka based on Bayesian Skyline and Skyride Plots. In contrast, Bayesian relaxed models of spatial diffusion suggested that range expansion occurred only between ~95 and 55 ka, and more recently, diffusion rates were very low during demographic expansion. The possibility of population growth without substantial range expansion could account for the shared patterns of demographic expansion during the Last Glacial Maxima (OIS 2 and 4) in fish, small mammals and other lizards of the Monte Desert. We found substantial variation in diffusion rates over time, and very high rates during the range expansion phase, consistent with a rapidly advancing expansion front towards the southeast shown by palaeo-distribution models. Furthermore, the estimated diffusion rates are congruent with observed dispersal rates of lizards in field conditions and therefore provide additional confidence to the temporal scale of inferred phylogeographic patterns. Our study highlights how the integration of phylogeography with palaeo-distribution models can shed light on both demographic and range expansion processes and their potential causes. © 2013 John Wiley & Sons Ltd.

  17. 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

  18. Consequences of introducing bryophytes and Arctic-shrubs in a land surface model with dynamical vegetation.

    Science.gov (United States)

    Druel, A.; Peylin, P.; Krinner, G.; Ciais, P.; Viovy, N.

    2016-12-01

    Recent developments of boreal vegetation in land surface models show the importance of new plant functional types for a better representation of physical and carbon cycle related processes in northern latitudes. In past climate transitions, shifts in northern vegetation played a crucial role, for example in the inception of the Last Glacial Maximum. With the current high-latitude warming, a greening of vegetation is observed, associated with increased shrub cover. It has thus become essential to include shifts in vegetation in models. In the ORCHIDEE land surface model with a dynamic vegetation, we introduced new parameterizations and processes associated to Arctic-shrubs, bryophytes (mosses and lichens) and boreal C3 grasses to simulate their effect on biomass, albedo, snow cover and soil thermal dynamic (including frozen soils). Specific competition and survival conditions are defined for these three plant functional types. Competition between herbaceous vegetation, shrubs and trees is based on available light. Survival conditions of shrubs include their protection from cold temperatures by snow, and the competition between C3 grasses and bryophytes depends especially on soil water-saturation conditions. The equilibrium fractional coverage of the three competing plant functional types is based on the net primary production. We compare the results from simulations with different configurations: 1) vegetation being either fixed prescribed from a satellite land cover map or dynamic and 2) plant functional types used being either the default settings of ORCHIDEE which include three different boreal tree types and one grassland type, or the latter plus the new boreal vegetation types. The simulations are run for the historical period and with an additional run of 100 years according to the RCP 4.5 and 8.5 climate scenarios. We evaluate the effect of new plant functional types on the vegetation distribution, and their consequences for energy, water and carbon fluxes

  19. 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.

  20. Risk assessment of vapor cloud explosions in a hydrogen production facility with consequence modeling.

    Science.gov (United States)

    Zarei, Esameil; Jafari, Mohammad Javad; Badri, Naser

    2013-09-17

    New technologies using hazardous materials usually have certain risks. It is more serious when the technology is supposed to be applied in a large scale and become widely used by many people. The objective of this paper was to evaluate the risk of vapor cloud explosion in a hydrogen production process. Potential hazards were identified using the conventional hazard identification method (HAZID). The frequency of the proposed scenarios was estimated from statistical data and existing records. The PHAST professional software was applied for consequence modeling. Both individual and societal risks were evaluated. This cross-sectional study was conducted from June 2010 to December 2011 in a Hydrogen Production Plant in Tehran. The full bore rupture in heat exchanger had the highest harm effect distance. The full bore rupture in desulphurization reactor had the highest (57% of total) individual risk. Full bore rupture in heat exchanger was the highest contributor to social risk. It carried 64% & 66.7% of total risk in day and night respectively. For the sake of safety, mitigation measures should be implemented on heat exchanger, reformer and hydrogen purification absorbers. The main proposed risk reductive measures included; the increasing of installed equipment elevation, the application of smaller vessels and pipes.

  1. 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)

  2. 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 ...

  3. 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...... modelling principle. The validation problem in relation to the model was discussed. A comparison between real and simulated data using data from a published case report was shown to illustrate how user acceptance can be obtained....

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

    Science.gov (United States)

    Jakobsen, Malene; Preda, Teodora; Kongsted, Anne Grete; Hermansen, John Erik

    2015-11-02

    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. 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.

  6. Practical Consequences of Item Response Theory Model Misfit in the Context of Test Equating with Mixed-Format Test Data.

    Science.gov (United States)

    Zhao, Yue; Hambleton, Ronald K

    2017-01-01

    In item response theory (IRT) models, assessing model-data fit is an essential step in IRT calibration. While no general agreement has ever been reached on the best methods or approaches to use for detecting misfit, perhaps the more important comment based upon the research findings is that rarely does the research evaluate IRT misfit by focusing on the practical consequences of misfit. The study investigated the practical consequences of IRT model misfit in examining the equating performance and the classification of examinees into performance categories in a simulation study that mimics a typical large-scale statewide assessment program with mixed-format test data. The simulation study was implemented by varying three factors, including choice of IRT model, amount of growth/change of examinees' abilities between two adjacent administration years, and choice of IRT scaling methods. Findings indicated that the extent of significant consequences of model misfit varied over the choice of model and IRT scaling methods. In comparison with mean/sigma (MS) and Stocking and Lord characteristic curve (SL) methods, separate calibration with linking and fixed common item parameter (FCIP) procedure was more sensitive to model misfit and more robust against various amounts of ability shifts between two adjacent administrations regardless of model fit. SL was generally the least sensitive to model misfit in recovering equating conversion and MS was the least robust against ability shifts in recovering the equating conversion when a substantial degree of misfit was present. The key messages from the study are that practical ways are available to study model fit, and, model fit or misfit can have consequences that should be considered when choosing an IRT model. Not only does the study address the consequences of IRT model misfit, but also it is our hope to help researchers and practitioners find practical ways to study model fit and to investigate the validity of particular IRT

  7. 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

  8. Some Demographic Changes in the Population of Montenegro with the Projection of Future Demographic Development

    Directory of Open Access Journals (Sweden)

    Goran Rajović

    2016-04-01

    Full Text Available Dramatic demographic changes through which in recent decade’s passes Montenegrin society, the consequences arising from the new realities require a serious socio-political engagement. Process of population aging, that began the seventies of the 20th century, represents a significant problem. The process of demographic change was accompanied by an internal migration to major urban centers, primarily Podgorica and Montenegrin coast, leading to emptying the interior of Montenegro. Unfortunately, this development of the population structure of Montenegro opens a series of questions and challenges that would the creators of the future you should put high on the scale of its priorities. In this text we will point out on change of total number of citizens of Montenegro according to the base and chain indexes of 1921-2011 and population in Montenegro 2016–2091 (cohort model projections.

  9. Consequences of increasing bioenergy demand on wood and forests: an application of the global forest products model

    Science.gov (United States)

    Joseph Buongiorno; Ronald Raunikar; Shushuai Zhu

    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...

  10. Modelling food safety and economic consequences of surveillance and control stratigegies for Salmonella in pigs and pork

    DEFF Research Database (Denmark)

    Baptista, Filipa M.; Hisham Beshara Halasa, Tariq; Alban, Liza R.

    2011-01-01

    Targets for maximum acceptable levels of Salmonella in pigs and pork are to be decided. A stochastic simulation model accounting for herd and abattoir information was used to evaluate food safety and economic consequences of different surveillance and control strategies, based among others...

  11. Geo-Demographic Risks in the Apuseni Mountains. Demographic Ageing

    Directory of Open Access Journals (Sweden)

    GABRIELA-ALINA MUREŞAN

    2014-12-01

    Full Text Available The territorial system of the Apuseni Mountains can be considered a critical region from a geo-demographic viewpoint. This is due to two major geo-demographic risks that affect it at present, namely the massive migration, mainly of the young and adult population, and the severe decrease in birth rate, also as a consequence of migration. These two processes determine the main two geo-demographic risks within the Apuseni Mountains: on the one hand, depopulation and the geo-demographic decline of the settlements and, on the other hand, population ageing. The present study aims to analyse the latter by focussing on the Land of the Moţi. Conclusions emphasise a rather severe process of demographic ageing. The rate of the old age group increased from 17.9% in 1992 to 25.2% in 2011. All the 16 administrative-territorial units under analysis recorded an increase in the rate of the old age group. In 2011, the ratio of the extreme age groups (young population/old age group is above the unit (1 both in the region as a whole and in the majority of its administrative units.

  12. Procedures Guide for Structural Expert Judgement in Accident Consequence Modelling (invited paper)

    International Nuclear Information System (INIS)

    Cooke, R.M.; Goossens, L.H.J.

    2000-01-01

    A protocol is outlined for using structured expert judgement to generate uncertainty data for uncertainty analyses. The use of performance based weighting as an instrument to enable optimisation of the aggregated experts' assessments is emphasised. Examples are shown from the EC/USNRC joint study on Probabilistic Accident Consequence Uncertainty Analysis. (author)

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

    Science.gov (United States)

    2015-09-30

    Application to North Atlantic Right Whales (Eubalaena glacialis) Scott D. Kraus Vice President of Research New England Aquarium Central Wharf, Boston...physiology, and the revised approach is called PCOD (Population Consequences Of Disturbance). In North Atlantic right whales (Eubalaena glacialis...visual observations of health, human impacts (including entanglements and ship strikes), and whale locations to provide estimates of true underlying

  14. Consequences of Symmetries on the Analysis and Construction of Turbulence Models

    Directory of Open Access Journals (Sweden)

    Dina Razafindralandy

    2006-05-01

    Full Text Available Since they represent fundamental physical properties in turbulence (conservation laws, wall laws, Kolmogorov energy spectrum, ..., symmetries are used to analyse common turbulence models. A class of symmetry preserving turbulence models is proposed. This class is refined such that the models respect the second law of thermodynamics. Finally, an example of model belonging to the class is numerically tested.

  15. 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

  16. The Bottlenose Dolphin (Tursiops truncatus) as a Model to Understand Variation in Stress and Reproductive Hormone Measures in Relation to Sampling Matrix, Demographics, and Environmental Factors

    Science.gov (United States)

    2015-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. FINAL REPORT The Bottlenose Dolphin (Tursiops truncatus...indicators and methods to quantify chronic stress in bottlenose dolphins . Much research had focused on the stimuli which induce stress in marine mammals, as...mammals was essential for understanding risks and long- term consequences for populations. OBJECTIVES Using the bottlenose dolphin as a model

  17. 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)

  18. 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...

  19. 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.

  20. 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...... 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...

  1. 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

  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. 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.

  4. 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

  5. Consequences of gas flux model choice on the interpretation of metabolic balance across 15 lakes

    Science.gov (United States)

    Dugan, Hilary; Woolway, R. Iestyn; Santoso, Arianto; Corman, Jessica; Jaimes, Aline; Nodine, Emily; Patil, Vijay; Zwart, Jacob A.; Brentrup, Jennifer A.; Hetherington, Amy; Oliver, Samantha K.; Read, Jordan S.; Winters, Kirsten; Hanson, Paul; Read, Emily; Winslow, Luke; Weathers, Kathleen

    2016-01-01

    Ecosystem metabolism and the contribution of carbon dioxide from lakes to the atmosphere can be estimated from free-water gas measurements through the use of mass balance models, which rely on a gas transfer coefficient (k) to model gas exchange with the atmosphere. Theoretical and empirically based models of krange in complexity from wind-driven power functions to complex surface renewal models; however, model choice is rarely considered in most studies of lake metabolism. This study used high-frequency data from 15 lakes provided by the Global Lake Ecological Observatory Network (GLEON) to study how model choice of kinfluenced estimates of lake metabolism and gas exchange with the atmosphere. We tested 6 models of k on lakes chosen to span broad gradients in surface area and trophic states; a metabolism model was then fit to all 6 outputs of k data. We found that hourly values for k were substantially different between models and, at an annual scale, resulted in significantly different estimates of lake metabolism and gas exchange with the atmosphere.

  6. Levofloxacin Population Pharmacokinetics and Creation of a Demographic Model for Prediction of Individual Drug Clearance in Patients with Serious Community-Acquired Infection

    Science.gov (United States)

    Preston, Sandra L.; Drusano, George L.; Berman, Adam L.; Fowler, Cynthia L.; Chow, Andrew T.; Dornseif, Bruce; Reichl, Veronica; Natarajan, Jaya; Wong, Frankie A.; Corrado, Michael

    1998-01-01

    Population pharmacokinetic modeling is a useful approach to obtaining estimates of both population and individual pharmacokinetic parameter values. The potential for relating pharmacokinetic parameters to pharmacodynamic outcome variables, such as efficacy and toxicity, exists. A logistic regression relationship between the probability of a successful clinical and microbiological outcome and the peak concentration-to-MIC ratio (and also the area under the plasma concentration-time curve [AUC]/MIC ratio) has previously been developed for levofloxacin; however, levofloxacin assays for determination of the concentration in plasma are not readily available. We attempted to derive and validate demographic variable models to allow prediction of the peak concentration in plasma and clearance (CL) from plasma for levofloxacin. Two hundred seventy-two patients received levofloxacin intravenously for the treatment of community-acquired infection of the respiratory tract, skin or soft tissue, or urinary tract, and concentrations in plasma, guided by optimal sampling theory, were obtained. Patient data were analyzed by the Non-Parametric Expectation Maximization approach. Maximum a posteriori probability Bayesian estimation was used to generate individual parameter values, including CL. Peak concentrations were simulated from these estimates. The first 172 patients were used to produce demographic models for the prediction of CL and the peak concentration. The remaining 100 patients served as the validation group for the model. A median bias and median precision were calculated. A two-compartment model was used for the population pharmacokinetic analysis. The mean CL and the mean volume of distribution of the central compartment (V1) were 9.27 liters/h and 0.836 liter/kg, respectively. The mean values for the intercompartmental rate constants, the rate constant from the central compartment to the peripheral compartment (Kcp) and the rate constant from the peripheral

  7. The Potential Consequence of Using Value-Added Models to Evaluate Teachers

    Science.gov (United States)

    Shen, Zuchao; Simon, Carlee Escue; Kelcey, Ben

    2016-01-01

    Value-added models try to separate the contribution of individual teachers or schools to students' learning growth measured by standardized test scores. There is a policy trend to use value-added modeling to evaluate teachers because of its face validity and superficial objectiveness. This article investigates the potential long term consequences…

  8. 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

  9. 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

  10. 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

  11. 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.

  12. 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

  13. Potential long-term consequences of fad diets on health, cancer, and longevity: lessons learned from model organism studies.

    Science.gov (United States)

    Ruden, Douglas M; Rasouli, Parsa; Lu, Xiangyi

    2007-06-01

    While much of the third world starves, many in the first world are undergoing an obesity epidemic, and the related epidemics of type II diabetes, heart disease, and other diseases associated with obesity. The amount of economic wealth being directly related to a decline in health by obesity is ironic because rich countries contribute billions of dollars to improve the health of their citizens. Nevertheless, nutritional experiments in model organisms such as yeast, C. elegans, Drosophila, and mice confirm that "caloric restriction" (CR), which is defined generally as a 30-40% decrease in caloric intake, a famine-like condition for humans seen only in the poorest of countries, promotes good health and increases longevity in model organisms. Because caloric restriction, and dieting in general, requires a great deal of will power to deal with the feelings of deprivation, many fad diets, such as the Atkins, South Beach, and Protein Power, have been developed which allow people to lose weight purportedly without the severe feelings of deprivation. However, the long-term effects of such fad diets are not known and few experiments have been performed in the laboratory to investigate possible side affects and adverse consequences. In this paper, we review studies with fad-like dietary conditions in humans and model organisms, and we propose a "Dietary Ames Test" to rapidly screen fad diets, dietary supplements, and drugs for potential long-term health consequences in model organisms.

  14. 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.)

  15. 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.

  16. 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

  17. 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.

  18. Modelling the cracking of pressurised water reactor fuel pellets and its consequences on the mechanical behaviour of the fuel rod

    International Nuclear Information System (INIS)

    Helfer, Th.

    2006-03-01

    This thesis aims to model the cracking of pressurised water reactor fuel pellets and its consequences on the mechanical behaviour of the fuel rod. Fuel cracking has two main consequences. It relieves the stress in the pellet, upon which the majority of the mechanical and physico-chemical phenomena are dependent. It also leads to pellet fragmentation. Taking fuel cracking into account is therefore necessary to adequately predict the mechanical loading of the cladding during the course of an irradiation. The local approach to fracture was chosen to describe fuel pellet cracking. Practical considerations brought us to favour a quasi-static description of fuel cracking by means of a local damage models. These models describe the appearance of cracks by a local loss of rigidity of the material. Such a description leads to numerical difficulties, such as mesh dependency of the results and abrupt changes in the equilibrium state of the mechanical structure during unstable crack propagations. A particular attention was paid to these difficulties because they condition the use of such models in engineering studies. This work was performed within the framework of the ALCYONE fuel performance package developed at CEA/DEC/SESC which relies on the PLEIADES software platform. ALCYONE provides users with various approaches for modelling nuclear fuel behaviour, which differ in terms of the type geometry considered for the fuel rod. A specific model was developed and implemented to describe fuel cracking for each of these approaches. The 2D axisymmetric fuel rod model is the most innovative and was particularly studied. We show that it is able to assess, thanks to an appropriate description of fuel cracking, the main geometrical changes of the fuel rod occurring under normal and off-normal operating conditions. (author)

  19. 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.

  20. 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...

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

    Energy Technology Data Exchange (ETDEWEB)

    Suolanen, V.; Ilvonen, M. [VTT Energy, Espoo (Finland). Nuclear Energy

    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{sup 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

  2. 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.

  3. 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.

  4. 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

  5. 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)

  6. 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...... 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...... 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...

  7. 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...

  8. 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...

  9. 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…

  10. Detecting Differential Item Discrimination (DID) and the Consequences of Ignoring DID in Multilevel Item Response Models

    Science.gov (United States)

    Lee, Woo-yeol; Cho, Sun-Joo

    2017-01-01

    Cross-level invariance in a multilevel item response model can be investigated by testing whether the within-level item discriminations are equal to the between-level item discriminations. Testing the cross-level invariance assumption is important to understand constructs in multilevel data. However, in most multilevel item response model…

  11. The Consequences of Ignoring Measurement Invariance for Path Coefficients in Structural Equation Models

    Directory of Open Access Journals (Sweden)

    Nigel eGuenole

    2014-09-01

    Full Text Available We report a Monte Carlo study examining the effects of 2 strategies for handling measurement non-invariance - modeling and ignoring non-invariant items - on structural regression coefficients between latent variables measured with Item Response Theory models for categorical indicators. These strategies were examined across 4 levels and 3 types of non-invariance – non-invariant loadings, non-invariant thresholds, and combined non-invariance on loadings and thresholds - in simple, partial, mediated and moderated regression models where the non-invariant latent variable occupied predictor, mediator, and criterion positions in the structural regression models. When non-invariance is ignored in the latent predictor, the focal group regression parameters are biased in the opposite direction to the difference in loadings and thresholds relative to the referent group (i.e. lower loadings and thresholds for the focal group lead to overestimated regression parameters. With criterion non-invariance, the focal group regression parameters are biased in the same direction as the difference in loadings and thresholds relative to the referent group. While unacceptable levels of parameter bias were confined to the focal group, bias occurred at considerably lower levels of ignored non-invariance than was previously recognized in referent and focal groups.

  12. Review on intrauterine programming: Consequences in rodent models of mild diabetes and mild fat overfeeding are not mild.

    Science.gov (United States)

    Jawerbaum, A; White, V

    2017-04-01

    An adverse intrauterine programming occurs in diabetes and obesity as the consequence of an adverse maternal environment that affects the appropriate fetoplacental development and growth. Experimental models of diabetes and fat overfeeding have provided relevant tools to address putative mechanisms of the adverse intrauterine programming. The current knowledge far extends from the original thoughts of the resulting intrauterine programming of metabolic and cardiovascular diseases to a full range of alterations that affect multiple tissues, organs, and systems that will compromise the long-life health of the offspring. This review examines the postnatal effects of rodent models of mild diabetes and fat overfeeding, identifying the multiple organ derangements in the offspring resulting from mild maternal adverse conditions. In addition, the comparison of experimental models of severe diabetes and fat overfeeding and the crucial role of the placenta are discussed, providing an update of the actual scenario of the putative mechanisms and adverse consequences of maternal metabolic derangements. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. 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.

  14. [The demographer's point of view].

    Science.gov (United States)

    Arias De Blois, J

    1993-03-01

    Although the predictable consequence of the acceleration of world population growth were foreseen 40 years ago, the need for population education did not become obvious until much later. Only in the 1960s did a number of countries become aware of changes in population dynamics and their implications for the quality of life and for socioeconomic development goals. Population phenomena and their implications are almost as poorly understood by most persons today as they were when the first population policies were announced. Population education has been viewed as a means of achieving a better understanding of population phenomena. It is believed that acquiring knowledge of population phenomena will promote responsible decision making on questions related to population problems. The early preoccupation in population education with fertility and family planning aroused considerable resistance. There is still strong resistance to including population dynamics and their implications in educational programs. But the most exclusive interest in family planning as a means of reducing the population explosion has broadened in response to a number of events including recognition of family planning as a human right, studies of the effects of high fertility on maternal-child health and education, the mortality decline in developing countries, and the strong increase in migratory movements resulting from urbanization and other causes. The university teaching of demography has become important only recently, and population education at the elementary and secondary level is more recent still. Each educational system must decide for itself the best bode of integrating demographic themes into the different disciplines. The principal demographic themes that should be incorporated will generally fit into existing programs of study. Because of the dynamic nature of demographic phenomena, the content of population education should be reviewed periodically with the assistance of a

  15. Cancer Stem Cells of Differentiated B-Cell Malignancies: Models and Consequences

    Energy Technology Data Exchange (ETDEWEB)

    Gross, Emilie; Quillet-Mary, Anne [INSERM, UMR1037-Cancer Research Center of Toulouse, 31300 Toulouse (France); ERL 5294 CNRS, BP3028 CHU Purpan, 31300 Toulouse (France); Université Toulouse III Paul-Sabatier, 31300 Toulouse (France); Ysebaert, Loic; Laurent, Guy [INSERM, UMR1037-Cancer Research Center of Toulouse, 31300 Toulouse (France); ERL 5294 CNRS, BP3028 CHU Purpan, 31300 Toulouse (France); Université Toulouse III Paul-Sabatier, 31300 Toulouse (France); Service d' Hématologie, CHU Purpan, 31300 Toulouse (France); Fournie, Jean-Jacques, E-mail: jean-jacques.fournie@inserm.fr [INSERM, UMR1037-Cancer Research Center of Toulouse, 31300 Toulouse (France); ERL 5294 CNRS, BP3028 CHU Purpan, 31300 Toulouse (France); Université Toulouse III Paul-Sabatier, 31300 Toulouse (France)

    2011-03-25

    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.

  16. 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

  17. 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.

  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. 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

  20. 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.

  1. 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.

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

    DEFF Research Database (Denmark)

    Rizzi, Silvia

    Vital statistics are often available to health researchers on a low resolution. In mortality analysis the distribution of deaths by age is often aggregated in groups of 5 years of age with a wide open-ended interval that sums a total for persons above age 85. The data that the researcher observes...... are therefore only an aggregate of true latent values. Grouping vital statistics in relatively wide bins before making them available is due to several reasons: Protect the privacy of patients; enable a compact presentation of the data; assemble scares observations; make them comparable with other databases...... a non-parametric method is developed to efficiently estimate age-at-death distributions and mortality rates from coarsely grouped data. The approach is based on a yet unexplored statistical model, the penalized composite link model, which extends generalized linear models. Observations are treated...

  3. Evaluation of demographic factors that influence acute radiation response.

    Science.gov (United States)

    Stricklin, Daniela; Millage, Kyle

    2012-08-01

    Casualty estimation tools are critical in planning for nuclear event scenarios. Current consequence assessment models based on healthy adult males may not adequately represent the population. To develop an understanding of the impact of demographic variables on casualty estimates, human data was surveyed to identify key demographic factors that affect acute radiation response. Information on in utero exposures, gender, age, and comorbidity status was collected from atomic bomb survivors, radiation accidents, and clinical oncology. Burn and trauma studies were also examined to gain insight into the impact of demographic variables on acute injury outcomes. Fetal radiation sensitivity is well documented; increased mortality or malformations are observed depending on gestational age. A greater incidence of radiation syndrome was observed among male atomic bomb survivors. Trauma data show increased mortality in males, apparently due to immunological differences between genders. Limited data suggest vulnerability in the very young and old due to immunological status and comorbidities, respectively. Certain genetically susceptible subpopulations demonstrate marked increased sensitivity to radiation exposure. Interaction of radiation and comorbid conditions has not been well studied; however, burn and trauma data indicate that comorbidities negatively impact response to acute injury. Key factors evaluated together with their prevalence indicate the importance of modeling demographic variability in casualty estimations. Also they can help identify vulnerable subpopulations and provide insight on treatment requirements.

  4. 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,…

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

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, H; Chen, W; Kligerman, S; D’Souza, W; Suntharalingam, M; Lu, W [University of Maryland School of Medicine, Baltimore, MD (United States); Tan, S [Huazhong University of Science and Technology, Wuhan (China); Kim, G [Duke University, High Point, NC (United States)

    2014-06-15

    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 {sup 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

  6. 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

  7. 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

  8. 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.

  9. Modeling consequences of prolonged strong unpredictable stress in zebrafish: Complex effects on behavior and physiology.

    Science.gov (United States)

    Song, Cai; Liu, Bai-Ping; Zhang, Yong-Ping; Peng, Zhilan; Wang, JiaJia; Collier, Adam D; Echevarria, David J; Savelieva, Katerina V; Lawrence, Robert F; Rex, Christopher S; Meshalkina, Darya A; Kalueff, Allan V

    2018-02-02

    Chronic stress is the major pathogenetic factor of human anxiety and depression. Zebrafish (Danio rerio) have become a novel popular model species for neuroscience research and CNS drug discovery. The utility of zebrafish for mimicking human affective disorders is also rapidly growing. Here, we present a new zebrafish model of clinically relevant, prolonged unpredictable strong chronic stress (PUCS). The 5-week PUCS induced overt anxiety-like and motor retardation-like behaviors in adult zebrafish, also elevating whole-body cortisol and proinflammatory cytokines - interleukins IL-1β and IL-6. PUCS also elevated whole-body levels of the anti-inflammatory cytokine IL-10 and increased the density of dendritic spines in zebrafish telencephalic neurons. Chronic treatment of fish with an antidepressant fluoxetine (0.1mg/L for 8days) normalized their behavioral and endocrine phenotypes, as well as corrected stress-elevated IL-1β and IL-6 levels, similar to clinical and rodent data. The CNS expression of the bdnf gene, the two genes of its receptors (trkB, p75), and the gfap gene of glia biomarker, the glial fibrillary acidic protein, was unaltered in all three groups. However, PUCS elevated whole-body BDNF levels and the telencephalic dendritic spine density (which were corrected by fluoxetine), thereby somewhat differing from the effects of chronic stress in rodents. Together, these findings support zebrafish as a useful in-vivo model of chronic stress, also calling for further cross-species studies of both shared/overlapping and distinct neurobiological responses to chronic stress. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. 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

  11. 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.

  12. 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.

  13. 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.

  14. 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 (

  15. 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...

  16. 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

  17. 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.)

  18. Social and economic antecedents and consequences of adolescent aggressive personality: Predictions from the interactionist model.

    Science.gov (United States)

    Conger, Rand D; Martin, Monica J; Masarik, April S; Widaman, Keith F; Donnellan, M Brent

    2015-11-01

    The present study examined the development of a cohort of 279 early adolescents (52% female) from 1990 to 2005. Guided by the interactionist model of socioeconomic status and human development, we proposed that parent aggressive personality, economic circumstances, interparental conflict, and parenting characteristics would affect the development of adolescent aggressive personality traits. In turn, we hypothesized that adolescent aggressiveness would have a negative influence on adolescent functioning as an adult in terms of economic success, personality development, and close relationships 11 years later. Findings were generally supportive of the interactionist model proposition that social and economic difficulties in the family of origin intensify risk for adolescent aggressive personality (the social causation hypothesis) and that this personality trait impairs successful transition to adult roles (the social selection hypothesis) in a transactional process over time and generations. These results underscore how early development leads to child influences that appear to directly hamper the successful transition to adult roles (statistical main effects) and also amplify the negative impact of dysfunctional family systems on the transition to adulthood (statistical interaction effects). The findings suggest several possible points of intervention that might help to disrupt this negative developmental sequence of events.

  19. 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.

  20. Modeling the Mechanical Consequences of Age-Related Trabecular Bone Loss by XFEM Simulation.

    Science.gov (United States)

    Fan, Ruoxun; Gong, He; Zhang, Xianbin; Liu, Jun; Jia, Zhengbin; Zhu, Dong

    2016-01-01

    The elderly are more likely to suffer from fracture because of age-related trabecular bone loss. Different bone loss locations and patterns have different effects on bone mechanical properties. Extended finite element method (XFEM) can simulate fracture process and was suited to investigate the effects of bone loss on trabecular bone. Age-related bone loss is indicated by trabecular thinning and loss and may occur at low-strain locations or other random sites. Accordingly, several ideal normal and aged trabecular bone models were created based on different bone loss locations and patterns; then, fracture processes from crack initiation to complete failure of these models were observed by XFEM; finally, the effects of different locations and patterns on trabecular bone were compared. Results indicated that bone loss occurring at low-strain locations was more detrimental to trabecular bone than that occurring at other random sites; meanwhile, the decrease in bone strength caused by trabecular loss was higher than that caused by trabecular thinning, and the effects of vertical trabecular loss on mechanical properties were more severe than horizontal trabecular loss. This study provided a numerical method to simulate trabecular bone fracture and distinguished different effects of the possible occurrence of bone loss locations and patterns on trabecular bone.

  1. Modeling the Mechanical Consequences of Age-Related Trabecular Bone Loss by XFEM Simulation

    Directory of Open Access Journals (Sweden)

    Ruoxun Fan

    2016-01-01

    Full Text Available The elderly are more likely to suffer from fracture because of age-related trabecular bone loss. Different bone loss locations and patterns have different effects on bone mechanical properties. Extended finite element method (XFEM can simulate fracture process and was suited to investigate the effects of bone loss on trabecular bone. Age-related bone loss is indicated by trabecular thinning and loss and may occur at low-strain locations or other random sites. Accordingly, several ideal normal and aged trabecular bone models were created based on different bone loss locations and patterns; then, fracture processes from crack initiation to complete failure of these models were observed by XFEM; finally, the effects of different locations and patterns on trabecular bone were compared. Results indicated that bone loss occurring at low-strain locations was more detrimental to trabecular bone than that occurring at other random sites; meanwhile, the decrease in bone strength caused by trabecular loss was higher than that caused by trabecular thinning, and the effects of vertical trabecular loss on mechanical properties were more severe than horizontal trabecular loss. This study provided a numerical method to simulate trabecular bone fracture and distinguished different effects of the possible occurrence of bone loss locations and patterns on trabecular bone.

  2. The business of demographics.

    Science.gov (United States)

    Russell, C

    1984-06-01

    The emergence of "demographics" in the past 15 years is a vital tool for American business research and planning. Tracing demographic trends became important for businesses when traditional consumer markets splintered with the enormous changes since the 1960s in US population growth, age structure, geographic distribution, income, education, living arrangements, and life-styles. The mass of reliable, small-area demographic data needed for market estimates and projections became available with the electronic census--public release of Census Bureau census and survey data on computer tape, beginning with the 1970 census. Census Bureau tapes as well as printed reports and microfiche are now widely accessible at low cost through summary tape processing centers designated by the bureau and its 12 regional offices and State Data Center Program. Data accessibility, plummeting computer costs, and businessess' unfamiliarity with demographics spawned the private data industry. By 1984, 70 private companies were offering demographic services to business clients--customized information repackaged from public data or drawn from proprietary data bases created from such data. Critics protest the for-profit use of public data by companies able to afford expensive mainframe computer technology. Business people defend their rights to public data as taxpaying ceitzens, but they must ensure that the data are indeed used for the public good. They must also question the quality of demographic data generated by private companies. Business' demographic expertise will improve when business schools offer training in demography, as few now do, though 40 of 88 graduate-level demographic programs now include business-oriented courses. Lower cost, easier access to business demographics is growing as more census data become available on microcomputer diskettes and through on-line linkages with large data bases--from private data companies and the Census Bureau itself. A directory of private and

  3. 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

  4. Review of models used for determining consequences of UF{sub 6} release: Development of model evaluation criteria. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Nair, S.K.; Chambers, D.B.; Park, S.H.; Hoffman, F.O. [Senes Oak Ridge, Inc., TN (United States). Center for Risk Analysis

    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{sub 6}-handling facilities, subsequent reactions of UF{sub 6} with atmospheric moisture, and the dispersion of UF{sub 6} and reaction products in the atmosphere. The study evaluates screening-level and detailed public-domain models that were specifically developed for UF{sub 6} and models that were originally developed for the treatment of dense gases but are applicable to UF{sub 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.

  5. 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

  6. 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.

  7. Modelling the ecological consequences of whole tree harvest for bioenergy production

    Science.gov (United States)

    Skår, Silje; Lange, Holger; Sogn, Trine

    2013-04-01

    There is an increasing demand for energy from biomass as a substitute to fossil fuels worldwide, and the Norwegian government plans to double the production of bioenergy to 9% of the national energy production or to 28 TWh per year by 2020. A large part of this increase may come from forests, which have a great potential with respect to biomass supply as forest growth increasingly has exceeded harvest in the last decades. One feasible option is the utilization of forest residues (needles, twigs and branches) in addition to stems, known as Whole Tree Harvest (WTH). As opposed to WTH, the residues are traditionally left in the forest with Conventional Timber Harvesting (CH). However, the residues contain a large share of the treés nutrients, indicating that WTH may possibly alter the supply of nutrients and organic matter to the soil and the forest ecosystem. This may potentially lead to reduced tree growth. Other implications can be nutrient imbalance, loss of carbon from the soil and changes in species composition and diversity. This study aims to identify key factors and appropriate strategies for ecologically sustainable WTH in Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) forest stands in Norway. We focus on identifying key factors driving soil organic matter, nutrients, biomass, biodiversity etc. Simulations of the effect on the carbon and nitrogen budget with the two harvesting methods will also be conducted. Data from field trials and long-term manipulation experiments are used to obtain a first overview of key variables. The relationships between the variables are hitherto unknown, but it is by no means obvious that they could be assumed as linear; thus, an ordinary multiple linear regression approach is expected to be insufficient. Here we apply two advanced and highly flexible modelling frameworks which hardly have been used in the context of tree growth, nutrient balances and biomass removal so far: Generalized Additive Models (GAMs) and

  8. 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

  9. 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.

  10. 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.

  11. 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

  12. Consequences of a future climatic scenario for the anchovy fishery in the Alboran Sea (SW Mediterranean): A modeling study

    Science.gov (United States)

    Macías, D.; Castilla-Espino, D.; García-del-Hoyo, J. J.; Navarro, G.; Catalán, I. A.; Renault, L.; Ruiz, J.

    2014-07-01

    The Alboran basin is one of the most productive areas of the Mediterranean Sea and supports an anchovy fishery with a history of remarkably variable landings. Past and present anchovy recruitment levels are highly sensitive to changes in the strength and direction of the incoming jet of Atlantic waters, which modulate the hydrographic features of the basin. Here, we analyze plausible consequences for the anchovy fisheries in the region based on a projected physical scenario for the end of the century obtained using a coupled hydrological-biogeochemical model. Our model predicts a substantial increase in horizontal water velocity and a negligible change in the associated biological production, which likely indicates reductions in anchovy stock, catches and revenues. Alternative policies are analyzed here for the economic scenario that is expected to emerge under future conditions of oceanographic features, pelagic ecosystem dynamics and anchovy landings in the Alboran Sea.

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

    Directory of Open Access Journals (Sweden)

    Bruno Ventelou

    Full Text Available AIM: 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. METHODS: 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. RESULTS: 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. CONCLUSION: Universal Access ART scaling-up strategies, which are more costly in the short term, remain the best economic

  14. The demographic consequences of U.S. Jewish population trends.

    Science.gov (United States)

    Schmelz, U O; Dellapergola, S

    1983-01-01

    This study is concerned with the population dynamics of the U.S. Jewish population. It is an extension of a previous study by Sidney Goldstein and develops the themes elaborated in that study in two directions: further investigation of nuptiality, fertility, and mixed marriage; and quantitative assessments of alternative projections of future population. The data are primarily taken from the National Jewish Population Study of 1970-1971. The authors conclude that the balance of internal population dynamics of U.S. Jewry is probably negative and, despite immigration, will become progressively more negative in the future.

  15. Demographic consequences of climate Change in the Uinta Ground Squirrel

    OpenAIRE

    Norman, Kari

    2016-01-01

    One important impact of climate change is shifts in the timing of life events such as reproduction and flowering. Hibernators like the Uinta Ground Squirrel are especially sensitive to potential shifts because they depend on food at essential times.

  16. 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.

  17. Structural updates of alignment of protein domains and consequences on evolutionary models of domain superfamilies.

    Science.gov (United States)

    Mutt, Eshita; Rani, Sudha Sane; Sowdhamini, Ramanathan

    2013-11-15

    Influx of newly determined crystal structures into primary structural databases is increasing at a rapid pace. This leads to updation of primary and their dependent secondary databases which makes large scale analysis of structures even more challenging. Hence, it becomes essential to compare and appreciate replacement of data and inclusion of new data that is critical between two updates. PASS2 is a database that retains structure-based sequence alignments of protein domain superfamilies and relies on SCOP database for its hierarchy and definition of superfamily members. Since, accurate alignments of distantly related proteins are useful evolutionary models for depicting variations within protein superfamilies, this study aims to trace the changes in data in between PASS2 updates. In this study, differences in superfamily compositions, family constituents and length variations between different versions of PASS2 have been tracked. Studying length variations in protein domains, which have been introduced by indels (insertions/deletions), are important because theses indels act as evolutionary signatures in introducing variations in substrate specificity, domain interactions and sometimes even regulating protein stability. With this objective of classifying the nature and source of variations in the superfamilies during transitions (between the different versions of PASS2), increasing length-rigidity of the superfamilies in the recent version is observed. In order to study such length-variant superfamilies in detail, an improved classification approach is also presented, which divides the superfamilies into distinct groups based on their extent of length variation. An objective study in terms of transition between the database updates, detailed investigation of the new/old members and examination of their structural alignments is non-trivial and will help researchers in designing experiments on specific superfamilies, in various modelling studies, in linking

  18. 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.

  19. Neurospora and the dead-end hypothesis: genomic consequences of selfing in the model genus.

    Science.gov (United States)

    Gioti, Anastasia; Stajich, Jason E; Johannesson, Hanna

    2013-12-01

    It is becoming increasingly evident that adoption of different reproductive strategies, such as sexual selfing and asexuality, greatly impacts genome evolution. In this study, we test theoretical predictions on genomic maladaptation of selfing lineages using empirical data from the model fungus Neurospora. We sequenced the genomes of four species representing distinct transitions to selfing within the history of the genus, as well as the transcriptome of one of these, and compared with available data from three outcrossing species. Our results provide evidence for a relaxation of purifying selection in protein-coding genes and for a reduced efficiency of transposable element silencing by Repeat Induced Point mutation. A reduction in adaptive evolution was also identified in the form of reduced codon usage bias in highly expressed genes of selfing Neurospora, but this result may be confounded by mutational bias. Potentially counteracting these negative effects, the nucleotide substitution rate and the spread of transposons is reduced in selfing species. We suggest that differences in substitution rate relate to the absence, in selfing Neurospora, of the asexual pathway producing conidia. Our results support the dead-end theory and show that Neurospora genomes bear signatures of both sexual and asexual reproductive mode. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  20. 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

  1. 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.

  2. 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

  3. 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.

  4. 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.

  5. 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

  6. 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

  7. 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

  8. 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.

  9. 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...

  10. Constrained consequence

    CSIR Research Space (South Africa)

    Britz, K

    2011-09-01

    Full Text Available and explicate one formal framework for a whole spectrum of consequence relations, flexible enough to be tailored for choices from a variety of contexts. They do so by investigating semantic constraints on classical entailment which give rise to a family of infra...

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

    DEFF Research Database (Denmark)

    Negendahl, Kristoffer

    to visualize any relevant building performance. AHP – the use of Analytic Hierarchy Process to clarify differences between solutions on both qualitative and quantitative evaluations. Termite – the implementation of the BPS tool solver Be10 as a plugin for Grasshopper that enables live feedback of entire...... building energy consumption. HQSS – a quasi-steady-state BPS tool solver dedicated for fast thermal analyses in Grasshopper. Moth – an agent-based optimization algorithm implemented in Grasshopper that attempts to combine qualitative and quantitative evaluations during optimization. Sentient models...... – a method to listen to user behaviour in Grasshopper and decrease the space of solutions. Surrogate models – a test of machine learning methods to speed up any BPS feedback through surrogate models with Grasshopper. This thesis demonstrates how integrated dynamic models may include building performance...

  12. 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

  13. 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

  14. 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.

  15. 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.

  16. The welfare state and demographic dividends

    Directory of Open Access Journals (Sweden)

    Gemma Abío

    2017-05-01

    Full Text Available Background: The demographic transition experienced by developed countries produces initial positive effects on economic growth ‒ the first demographic dividend ‒ which can be extended into a second demographic dividend if baby boomers' savings increase capital accumulation. Nevertheless, aging might reverse this process if dissaving of elderly baby boomers and the pressure on the pay-as-you-go financed welfare state reduce savings and capital. Objective: The aim of this paper is to evaluate the extent to which demographic dividends in Spain provide an opportunity for the reform of the welfare state system for an aging population. Methods: We decompose demographic dividends using a general equilibrium overlapping generations model with realistic demography and public transfers from the National Transfer Accounts database. This allows us to capture the endogenous evolution of savings and capital accumulation and, hence, the second demographic dividend. Results: When baby boomers enter the labor market, the purely demographic support ratio increases and this positive effect is extended by composition changes in the age structure of workers. When they start saving, the second demographic dividend arises, while its total net effect depends both on the strength of the aging process and on transfer size. Conclusions: The derived decomposition shows that the second demographic dividend might also disappear. Sharp population aging in Spain implies that capital will shrink drastically after 2040. Before this, there seems to be margin for reforms; however, an extension of the welfare state toward the Nordic model would considerably reduce capital. Contribution: This paper contributes to the debate on the effects of demographics on economic growth by decomposing demographic dividends and investigating the impact of different welfare state transfer systems on the second demographic dividend.

  17. Examination of the Two Models of Subjective Well-Being and Correlations between Satisfaction with Life, Demographic Variables and Personality Traits

    Directory of Open Access Journals (Sweden)

    Ivana Lučev

    2010-12-01

    Full Text Available The goal of this study was to further the understanding of complex processes that are the base for feelings and satisfaction judgments by examining two models of subjective well-being. 1048 participants rated satisfaction with life and filled out IPIP-50 questionnaire that measures personality traits of the Big five model and demographic data questionnaire. Satisfaction with life in general was statistically significantly positively correlated with satisfaction of relationships with other people, satisfaction with health as well as with specific aspects of these domains. As was expected according to judgment model, correlations were higher for global domains than for specific aspects of satisfaction except for satisfaction with mood. Hypothesis of general positivity model and judgment model were tested in a series of hierarchical regression analyses. General life satisfaction explained variance of both global domains above and beyond satisfaction with corresponding specific domains. Contribution of global life satisfaction was significant even after effect of big five personality traits was controlled. Personality traits of the Big five model were statistically significantly associated with general life satisfaction. Correlation coefficients were -0.41 for Neuroticism, 0.30 for Extraversion, 0.14 for Agreeableness, 0.13 for Conscientiousness and 0.22 for Intellect. Age, education and being in a relationship were positively correlated with general life satisfaction. In this connection younger, better educated persons and those being in relationship were more satisfied with life in general. Women had higher levels of satisfaction for relationship with parents, while men had higher levels of satisfaction with partner, mobility, energy level, immunity and absence of pain.

  18. Bet Hedging against Demographic Fluctuations

    Science.gov (United States)

    Xue, BingKan; Leibler, Stanislas

    2017-09-01

    Biological organisms have to cope with stochastic variations in both the external environment and the internal population dynamics. Theoretical studies and laboratory experiments suggest that population diversification could be an effective bet-hedging strategy for adaptation to varying environments. Here we show that bet hedging can also be effective against demographic fluctuations that pose a trade-off between growth and survival for populations even in a constant environment. A species can maximize its overall abundance in the long term by diversifying into coexisting subpopulations of both "fast-growing" and "better-surviving" individuals. Our model generalizes statistical physics models of birth-death processes to incorporate dispersal, during which new populations are founded, and can further incorporate variations of local environments. In this way, we unify different bet-hedging strategies against demographic and environmental variations as a general means of adaptation to both types of uncertainties in population growth.

  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. Consequences of recurrent gene flow from crops to wild relatives.

    OpenAIRE

    Haygood, Ralph; Ives, Anthony R; Andow, David A

    2003-01-01

    Concern about gene flow from crops to wild relatives has become widespread with the increasing cultivation of transgenic crops. Possible consequences of such gene flow include genetic assimilation, wherein crop genes replace wild ones, and demographic swamping, wherein hybrids are less fertile than their wild parents, and wild populations shrink. Using mathematical models of a wild population recurrently receiving pollen from a genetically fixed crop, we find that the conditions for genetic a...

  1. Incorporating environmental attitudes in discrete choice models: an exploration of the utility of the awareness of consequences scale.

    Science.gov (United States)

    Hoyos, David; Mariel, Petr; Hess, Stephane

    2015-02-01

    Environmental economists are increasingly interested in better understanding how people cognitively organise their beliefs and attitudes towards environmental change in order to identify key motives and barriers that stimulate or prevent action. In this paper, we explore the utility of a commonly used psychometric scale, the awareness of consequences (AC) scale, in order to better understand stated choices. The main contribution of the paper is that it provides a novel approach to incorporate attitudinal information into discrete choice models for environmental valuation: firstly, environmental attitudes are incorporated using a reinterpretation of the classical AC scale recently proposed by Ryan and Spash (2012); and, secondly, attitudinal data is incorporated as latent variables under a hybrid choice modelling framework. This novel approach is applied to data from a survey conducted in the Basque Country (Spain) in 2008 aimed at valuing land-use policies in a Natura 2000 Network site. The results are relevant to policy-making because choice models that are able to accommodate underlying environmental attitudes may help in designing more effective environmental policies. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Accident consequence analysis

    International Nuclear Information System (INIS)

    Nixon, W.; Cooper, P.J.; Underwood, B.Y.; Peckover, R.S.

    1985-01-01

    The essential elements of an analysis of the radiological consequences of accidental atmospheric releases from nuclear plant are identified and the modelling approaches currently used briefly outlined. For the model description attention is focused on the techniques used within the context of a probabilistic risk assessment. This is followed by a brief outline of current research and development work in the field, allowing an indication of the nature of the next generation of consequence assessment methods. (author)

  3. Demographic modelling approach for assessment of environmental conditions which control the population of the invasive Ctenophore Mnemiopsis leidyi in the Mediterranean Seas.

    Science.gov (United States)

    Shiganova, Tamara; Nival, Paul; Carlotti, Francois; Alekseenko, Elena

    2017-04-01

    At the beginning of the 1980s predatory ctenophore Mnemiopsis leidyi (M.l.) invaded into the Black Sea, successfully established and gave huge blooms. As a result biodiversity of the representative of all levels of ecosystem greatly dropped as well as fishery stocks. In the following years, M.leidyi penetrated in all the seas of the Mediterranean basin with currents and with ballast water in the Caspian Sea. According to genetic analyses performed by Ghabooli et al. (2013) the distribution of genetic diversity and pattern of genetic differentiation determined the initial colonization of the Mediterranean, Azov, Caspian seas from the Black Sea. Ten years later, another ctenophore Beroe ovata (B.o.), a predator of M.l., spontaneously arrived in the Black Sea and the ecosystem started to recover its previous biodiversity (Shiganova et al., 2014). However, in recent years M.l. blooms are more and more observed in the other coastal areas of the Mediterranean basin. Therefore, the drivers (environmental conditions) of these blooms are still questioned and should be further studied in details. The main objective is to understand the environmental conditions which favors blooms of the ctenophore Mnemiopsis leidyi and its dispersal in the Mediterranean basin, which is characterized by a strong anthropogenic impact and even in some areas the degradation of coastal ecosystems. Modeling based on long-term field and experimental data of demographical and physiological parameters of M.l. help us to understand the conditions facilitated blooms in the Mediterranean basin based on the responses of underlying processes (growth and reproduction, predation) to environmental factors. The demographic model (MBd) used for this purpose include the main developmental stages of both ctenophores, their duration in function of temperature and zooplankton concentration. It was considered that the timing of growth of both species M.l. and B.o. is crucial in their interaction. At first

  4. 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.

  5. Review of the chronic exposure pathways models in MACCS (MELCOR Accident Consequence Code System) and several other well-known probabilistic risk assessment models

    Energy Technology Data Exchange (ETDEWEB)

    Tveten, U. (Institutt for Energiteknikk, Kjeller (Norway))

    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.

  6. 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

  7. 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.

  8. Shifting towards a model of mGluR5 dysregulation in schizophrenia: Consequences for future schizophrenia treatment.

    Science.gov (United States)

    Matosin, Natalie; Fernandez-Enright, Francesca; Lum, Jeremy S; Newell, Kelly A

    2017-03-15

    Metabotropic glutamate receptor subtype 5 (mGluR5), encoded by the GRM5 gene, represents a compelling novel drug target for the treatment of schizophrenia. mGluR5 is a postsynaptic G-protein coupled glutamate receptor strongly linked with several critical cellular processes that are reported to be disrupted in schizophrenia. Accordingly, mGluR5 positive allosteric modulators show encouraging therapeutic potential in preclinical schizophrenia models, particularly for the treatment of cognitive dysfunctions against which currently available therapeutics are largely ineffective. More work is required to support the progression of mGluR5-targeting drugs into the clinic for schizophrenia treatment, although some obstacles may be overcome by comprehensively understanding how mGluR5 itself is involved in the neurobiology of the disorder. Several processes that are necessary for the regulation of mGluR5 activity have been identified, but not examined, in the context of schizophrenia. These processes include protein-protein interactions, dimerisation, subcellular trafficking, the impact of genetic variability or mutations on protein function, as well as epigenetic, post-transcriptional and post-translational processes. It is essential to understand these aspects of mGluR5 to determine whether they are affected in schizophrenia pathology, and to assess the consequences of mGluR5 dysfunction for the future use of mGluR5-based drugs. Here, we summarise the known processes that regulate mGluR5 and those that have already been studied in schizophrenia, and discuss the consequences of this dysregulation for current mGluR5 pharmacological strategies. This article is part of the Special Issue entitled 'Metabotropic Glutamate Receptors, 5 years on'. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Toward the Multilevel Older Person's Transportation and Road Safety Model: A New Perspective on the Role of Demographic, Functional, and Psychosocial Factors.

    Science.gov (United States)

    Wong, Ides Y; Smith, Simon S; Sullivan, Karen A; Allan, Alicia C

    2016-01-01

    Self-regulation refers to the practice of using self-imposed restrictions to protect oneself from situations that are, or are perceived to be, unsafe. Within the driving context, self-regulation refers the compensatory practices that some older adults adopt to restrict their driving to situations in which they feel safe. However, the way in which demographic, functional, and psychosocial factors, and the interactions between these factors, influence older adults' driving self-regulation is not well understood. Improving this understanding could lead to new ways of considering the mobility concerns faced by older drivers. A systematic review of the current literature was conducted to explore this issue. Twenty-nine empirical studies investigating the factors associated with older adults' self-regulatory driving behaviors were examined. The review findings were used to construct the Multilevel Older Persons Transportation and Road Safety (MOTRS) model. The MOTRS model proposes that individual and environmental factors such as age, gender, and the availability of alternative transportation predict older adults' practice of driving-related self-regulation. However, these variables influence self-regulation through psychosocial variables such as driving confidence, affective attitude, and instrumental attitude toward driving. The MOTRS model extends previous attempts to model older adults' driving by focusing on a novel target, driving self-regulation, and by including a wider range of predictors identified on the basis of the systematic literature review. This focus enables consideration of broader mobility issues and may inform new strategies to support the mobility of older adults. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. 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.

  11. 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

  12. DEMOGRAPHIC SECURITY: THEORY, METHODOLOGY, EVALUATION

    Directory of Open Access Journals (Sweden)

    Mikhail V. Karmanov

    2015-01-01

    Full Text Available The paper analyzes the theoretical aspects of demographic security. Reviewed and analyzed the point of view of various scholars to the definition of demographic security. The main directions of statistical analysis of demographic security.

  13. Repeated Demographic-Structural Crises Propel the Spread of Large-scale Agrarian States Throughout the Old World

    Directory of Open Access Journals (Sweden)

    James Bennett

    2016-06-01

    Full Text Available I investigate the geographical consequences of demographic-structural dynamics using a spatially resolved agent-based model of agrarian empires in several Old World regions between 1500 BCE and 1500 CE. I estimate and bound key model parameters from two historical datasets. Although several very large-scale polities (e.g., Roman, Persian, Tang empires do not arise and certain geographical expansions occur at different times, overall the model suggests that factional civil wars, the result of repeated internal demographic-structural crises, can substantially account for the spread of large-scale agriculture throughout the Old World after the Bronze Age.

  14. HISTOPATHOLOGIC AND DEMOGRAPHIC

    African Journals Online (AJOL)

    Esem

    ABSTRACT. Background: Thyroid gland disease is a common disorder of the endocrine system worldwide.This disease varies according to the environment. The aim of this study is to determine demographic and histopathologic patterns of thyroid disease at the University Teaching Hospital,. Lusaka, Zambia. Methods: This ...

  15. 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...

  16. 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…

  17. Modeling the Impacts of Two Bark Beetle Species Under a Warming Climate in the Southwestern USA: Ecological and Economic Consequences

    Science.gov (United States)

    Waring, Kristen M.; Reboletti, Danielle M.; Mork, Lauren A.; Huang, Ching-Hsun; Hofstetter, Richard W.; Garcia, Amanda M.; Fulé, Peter Z.; Davis, T. Seth

    2009-10-01

    Predicted climate warming is expected to have profound effects on bark beetle population dynamics in the southwestern United States. Temperature-mediated effects may include increases in developmental rates, generations per year, and changes in habitat suitability. As a result, the impacts of Dendroctonus frontalis and Dendroctonus mexicanus on forest resources are likely subject to amplification. To assess the implications of such change, we evaluated the generations per year of these species under three climate scenarios using a degree-day development model. We also assessed economic impacts of increased beetle outbreaks in terms of the costs of application of preventative silvicultural treatments and potential economic revenues forgone. Across the southwestern USA, the potential number of beetle generations per year ranged from 1-3+ under historical climate, an increase of 2-4+ under the minimal warming scenario and 3-5+ under the greatest warming scenario. Economic benefits of applying basal area reduction treatments to reduce forest susceptibility to beetle outbreaks ranged from 7.75/ha (NM) to 95.69/ha (AZ) under historical conditions, and 47.96/ha (NM) to 174.58/ha (AZ) under simulated severe drought conditions. Basal area reduction treatments that reduce forest susceptibility to beetle outbreak result in higher net present values than no action scenarios. Coupled with other deleterious consequences associated with beetle outbreaks, such as increased wildfires, the results suggest that forest thinning treatments play a useful role in a period of climate warming.

  18. 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.

  19. 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.

  20. Demographic Growth and the Distribution of Language Sizes

    Science.gov (United States)

    Zanette, Damián H.

    It is argued that the present log-normal distribution of language sizes is, to a large extent, a consequence of demographic dynamics within the population of speakers of each language. A two-parameter stochastic multiplicative process is proposed as a model for the population dynamics of individual languages, and applied over a period spanning the last ten centuries. The model disregards language birth and death. A straightforward fitting of the two parameters, which statistically characterize the population growth rate, predicts a distribution of language sizes in excellent agreement with empirical data. Numerical simulations, and the study of the size distribution within language families, validate the assumptions at the basis of the model.

  1. Consequences of nocturnal water loss: a synthesis of regulating factors and implications for capacitance, embolism and use in models.

    Science.gov (United States)

    Zeppel, M J B; Lewis, J D; Phillips, N G; Tissue, D T

    2014-10-01

    Total daily water use is a key factor influencing the growth of many terrestrial plants, and reflects both day-time and nocturnal water fluxes. However, while nocturnal sap flow (En) and stomatal conductance (gs,n) have been reported across a range of species, ecosystems and microclimatic conditions, the regulation of these fluxes remains poorly understood. Here, we present a framework describing the role of abiotic and biotic factors in regulating En and gs,n highlighting recent developments in this field. Across ecosystems, En and gs,n generally increased with increasing soil water content and vapor pressure deficit, but the interactive effects of these factors and the potential roles of wind speed and other abiotic factors remain unclear. On average, gs,n and En are higher in broad-leaved compared with needle-leaved plants, in C3 compared with C4 plants, and in tropical compared with temperate species. We discuss the impacts of leaf age, elevated [CO2] and refilling of capacitance on night-time water loss, and how nocturnal gs,n may be included in vegetation models. Younger leaves may have higher gs,n than older leaves. Embolism refilling and recharge of capacitance may affect sap flow such that total plant water loss at night may be less than estimated solely from En measurements. Our estimates of gs,n for typical plant functional types, based on the published literature, suggest that nocturnal water loss may be a significant fraction (10-25%) of total daily water loss. Counter-intuitively, elevated [CO2] may increase nocturnal water loss. Assumptions in process-based ecophysiological models and dynamic global vegetation models that gs is zero when solar radiation is zero are likely to be incorrect. Consequently, failure to adequately consider nocturnal water loss may lead to substantial under-estimation of total plant water use and inaccurate estimation of ecosystem level water balance. © The Author 2014. Published by Oxford University Press. All rights

  2. Phenotypic consequences of copy number variation: insights from Smith-Magenis and Potocki-Lupski syndrome mouse models.

    Directory of Open Access Journals (Sweden)

    Guénola Ricard

    2010-11-01

    Full Text Available A large fraction of genome variation between individuals is comprised of submicroscopic copy number variation of genomic DNA segments. We assessed the relative contribution of structural changes and gene dosage alterations on phenotypic outcomes with mouse models of Smith-Magenis and Potocki-Lupski syndromes. We phenotyped mice with 1n (Deletion/+, 2n (+/+, 3n (Duplication/+, and balanced 2n compound heterozygous (Deletion/Duplication copies of the same region. Parallel to the observations made in humans, such variation in gene copy number was sufficient to generate phenotypic consequences: in a number of cases diametrically opposing phenotypes were associated with gain versus loss of gene content. Surprisingly, some neurobehavioral traits were not rescued by restoration of the normal gene copy number. Transcriptome profiling showed that a highly significant propensity of transcriptional changes map to the engineered interval in the five assessed tissues. A statistically significant overrepresentation of the genes mapping to the entire length of the engineered chromosome was also found in the top-ranked differentially expressed genes in the mice containing rearranged chromosomes, regardless of the nature of the rearrangement, an observation robust across different cell lineages of the central nervous system. Our data indicate that a structural change at a given position of the human genome may affect not only locus and adjacent gene expression but also "genome regulation." Furthermore, structural change can cause the same perturbation in particular pathways regardless of gene dosage. Thus, the presence of a genomic structural change, as well as gene dosage imbalance, contributes to the ultimate phenotype.

  3. 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.

  4. Experimental Modelling of the Consequences of Brief Late Gestation Asphyxia on Newborn Lamb Behaviour and Brain Structure

    Science.gov (United States)

    Yawno, Tamara; Witjaksono, Anissa; Miller, Suzie L.; Walker, David W.

    2013-01-01

    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. PMID:24223120

  5. Phenotypic consequences of copy number variation: insights from Smith-Magenis and Potocki-Lupski syndrome mouse models.

    Science.gov (United States)

    Ricard, Guénola; Molina, Jessica; Chrast, Jacqueline; Gu, Wenli; Gheldof, Nele; Pradervand, Sylvain; Schütz, Frédéric; Young, Juan I; Lupski, James R; Reymond, Alexandre; Walz, Katherina

    2010-11-23

    A large fraction of genome variation between individuals is comprised of submicroscopic copy number variation of genomic DNA segments. We assessed the relative contribution of structural changes and gene dosage alterations on phenotypic outcomes with mouse models of Smith-Magenis and Potocki-Lupski syndromes. We phenotyped mice with 1n (Deletion/+), 2n (+/+), 3n (Duplication/+), and balanced 2n compound heterozygous (Deletion/Duplication) copies of the same region. Parallel to the observations made in humans, such variation in gene copy number was sufficient to generate phenotypic consequences: in a number of cases diametrically opposing phenotypes were associated with gain versus loss of gene content. Surprisingly, some neurobehavioral traits were not rescued by restoration of the normal gene copy number. Transcriptome profiling showed that a highly significant propensity of transcriptional changes map to the engineered interval in the five assessed tissues. A statistically significant overrepresentation of the genes mapping to the entire length of the engineered chromosome was also found in the top-ranked differentially expressed genes in the mice containing rearranged chromosomes, regardless of the nature of the rearrangement, an observation robust across different cell lineages of the central nervous system. Our data indicate that a structural change at a given position of the human genome may affect not only locus and adjacent gene expression but also "genome regulation." Furthermore, structural change can cause the same perturbation in particular pathways regardless of gene dosage. Thus, the presence of a genomic structural change, as well as gene dosage imbalance, contributes to the ultimate phenotype.

  6. 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.

  7. 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

  8. Consequence analysis of depressurization accidents

    International Nuclear Information System (INIS)

    Foley, J.E.

    1976-01-01

    The consequences of the depressurization accidents for the High-Temperature Gas-Cooled Reactor are investigated. A consequence model is developed that is used to delineate the parameters that are important to the consequence calculations. A numerical example of the calculational technique is given

  9. THE EVOLUTION OF THE MAIN DEMOGRAPHIC PHENOMENA IN ROMANIA

    Directory of Open Access Journals (Sweden)

    MANUELA-DORA ORBOI

    2008-05-01

    Full Text Available The trends of the main demographic phenomena provide useful information about the future evolution of the number and age structure of Romania’s population. The mutations in the social-economic structure of the country have led to a dynamic territorial mobility of the population; at the same time, they have direct consequences upon the socio-demographic structure of the population. In the past years, demographic migration has become a common fact. The young and mature population migrates from the rural to the urban environment, motivated by the living and working conditions in the urban centers. Consequently, the remaining rural inhabitants are mostly old-aged. The aging of the rural population is also caused by a series of demographic and social-economic factors. The economic effects of the demographic evolution will be seen in time and will bring about changes in the various subpopulations (school children, fertile population, inhabitants able to work.

  10. 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

  11. 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

  12. The demographic effects of technological change and capitalist transformation--a re-interpretation of the demographic transition theory.

    Science.gov (United States)

    Maitra, P

    1992-06-01

    The interrelationship between demographic transition, capitalist transformation, and technological change in the 2 contrasting cases of the UK and India is explored. In the UK, technological change evolved from the extensive to the intensive phase, while technological change was introduced in India from the UK and other developed economies. The Demographic Transition Model is re-examined for these cases while the extensive and intensive phases of technological change with their effects on labor demand and consequent effects on fertility rate are analyzed. Changes in economic structure, demography, and factor pricing systems are presented as indicators of capitalist transformation of an economy. At the onset of capitalist transformation, population growth tends to decline as a result of increasing demand for labor in productive activities. Accordingly, the pattern of population growth depends upon the growth of demand for labor in productive activities which in turn depends upon the nature of the source of technological change; Demographic Transition theory ignores this point. Debate remains over whether imported technology, once reaching maturity, may effect capitalist transformation of economies toward true integrated development.

  13. Stock vs. Bond Yields, and Demographic Fluctuations

    DEFF Research Database (Denmark)

    Gozluklu, Arie; Morin, Annaïg

    that the slow-evolving time-series covariation due to changing population age structure accounts for the equilibrium relation between stock and bond markets. As a result, by exploiting the demographic information into distant future, the forecasting performance of evaluation models improves. Finally, using...... a cross-country panel, we document the cross-sectional variation of the demographic effect and explain the cross-country differences in comovement between stock and bond markets....

  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. 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...

  16. 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...

  17. 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.

  18. 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.

  19. A West Virginia case study: does erosion differ between streambanks clustered by the bank assessment of nonpoint source consequences of sediment (BANCS) model parameters?

    Science.gov (United States)

    Abby L. McQueen; Nicolas P. Zegre; Danny L. Welsch

    2013-01-01

    The integration of factors and processes responsible for streambank erosion is complex. To explore the influence of physical variables on streambank erosion, parameters for the bank assessment of nonpoint source consequences of sediment (BANCS) model were collected on a 1-km reach of Horseshoe Run in Tucker County, West Virginia. Cluster analysis was used to establish...

  20. Modeling Relationships between Two Categorical Variables When Data Are Missing: Examining Consequences of the Missing Data Mechanism in an HIV Data Set.

    Science.gov (United States)

    Strauss, Shiela M.; Rindskopf, David M.; Falkin, Gregory P.

    2001-01-01

    Used empirical data about HIV risk behaviors from 330 female participants in a drug treatment program to explore the implications and consequences of using various statistical models to describe the association of one ordinal and one dichotomous variable in which data are incomplete for the dichotomous variable. Examined the statistical fit and…

  1. China's Demographic Dilemmas.

    Science.gov (United States)

    Tien, H. Yuan; And Others

    1992-01-01

    China's herculean efforts to slow the increase of its giant population appear to have worked: the annual birth rate fell from about 35 births per 1,000 in the 1950s to 20 per 1,000 in the 1990s. This bulletin examines the development and consequences of the strict population planning control measures introduced in the 1970s, and strengthened in…

  2. A tree of impact model. Evaluation of consequences of repeal of the abortion law on teenage pregnancy.

    Science.gov (United States)

    Horner, S D; Hilde, E

    1991-01-01

    Teenage pregnancy is a complex issue in the current sociopolitical milieu. The enactment of abortion laws adds to the complexity of the problem, involving moral and ethical issues, as well as social, economic, and health status consequences that should be considered in the development of legislation surrounding this issue. The tree of impact diagram is a mechanism for forecasting possible consequences of abortion laws. Historical, social, developmental, economic, and legal forces are considered in creating the tree of impact in relation to the health and well-being of teenage mothers and their children.

  3. 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

  4. 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…

  5. 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.

  6. 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

  7. 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...

  8. 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

  9. Using Ontologies to Support Model-based Exploration of the Dependencies between Causes and Consequences of Hazards

    OpenAIRE

    Bloomfield, R. E.; Parisaca-Vargas, A.

    2015-01-01

    Hazard identification and hazard analysis are difficult and essential parts of safety engineering. These activities are very demanding and mostly manual. There is an increasing need for improved analysis tools and techniques. In this paper we report research that focuses on supporting the early stages of hazard identification. A state-based hazard analysis process is presented to explore dependencies between causes and consequences of hazards. The process can be used to automate the analysis ...

  10. 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.

  11. 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.

  12. 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

    is equipped with an MFM Model Editing Interface to facilitate the modelling process and MFM model analysis modules to run diag nosis and prognosis analyses based on developed models. New features of the MFM Suite also include making corresponding process diagram for the plant being modelled with MFM...... 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......Multilevel Flow Modelling (MFM) is a functional modelling methodology which applies means - end and parts - whole decomposition and aggregation techniques to handle the complexity of engineering systems. It has been adopted in several case studies to model the process goal and functions of PWR...

  13. 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 t...

  14. Improving public health training and research capacity in Africa: a replicable model for linking training to health and socio-demographic surveillance data.

    Science.gov (United States)

    Williams, Jill R; Schatz, Enid J; Clark, Benjamin D; Collinson, Mark A; Clark, Samuel J; Menken, Jane; Kahn, Kathleen; Tollman, Stephen M

    2010-08-31

    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. To increase research training capacity in public health programs by providing targeted training to students and increasing the accessibility of existing data. 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. 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.

  15. 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.

  16. 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.

  17. 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

  18. Contemporary demographic changes of the Rasina district

    OpenAIRE

    Stričević, Ljiljana; Radivojević, Aleksandar; Golubović, Ninoslav; Miletić, Jelena; Milić, Jana

    2016-01-01

    Rasina District is faced with serious demographic problems at the beginning of the twenty-first century which are the consequence of long-term economic and social changes both in this area and the country as a whole. The basic problem is insufficient population regeneration, which further leads to other negative processes. One of the most important problems of Rasina District is the ageing of population, i.e., a drop in young population and a significant rise in old population. Therefore, the...

  19. Single Large Impacts and their Consequences on the Evolution of a Coupled Atmosphere-Interior Venus Model

    Science.gov (United States)

    Gillmann, C.; Golabek, G.; Tackley, P.

    2015-12-01

    We investigate the effect of a single large impact during the Late Veneer and Late Heavy Bombardment on the evolution of the mantle and atmosphere of Venus. We use a coupled interior/exterior numerical code based on StagYY and developed in Gillmann and Tackley [2014]. Single vertical impacts are simulated as instantaneous events affecting both the atmosphere and mantle of the planet by (i) eroding the atmosphere, causing atmospheric escape, and (ii) depositing energy in the crust and mantle of the planet. Main impactor parameters include timing, size/mass, velocity and efficiency of energy deposition. We observe that volatile delivery by the impactor and impact erosion of the atmosphere are both minor effects compared to melting and degassing triggered by the energy deposited in the mantle and crust. Small collisions (under 100 km radius) have only local and time-limited effects. Medium-sized impactors (100-300 km) will not have much more consequences unless the energy deposition is enhanced, for example by a fast collision. In that case, it will have comparable effects to the larger category of impacts (400-800 km): a strong thermal anomaly affecting both crust and mantle and triggering melting and a change in mantle dynamics patterns. Such an impact is a global event and can be responsible for volcanic events focused at the impact location and near the antipode. Depending on the timing of the impact, it can also have major consequences on the long-term evolution of the planet and its surface conditions by either (i) efficiently depleting the upper mantle of the planet, leading to the early loss of its water or (ii) imposing a volatile rich and hot atmosphere for billions of years. Due to the coupled nature of the evolution, both cases can affect the evolution of the whole planet (atmosphere and interior) on the long term.

  20. 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

  1. International trade with pensions and demographic shock

    NARCIS (Netherlands)

    Fedotenkov, I.; van Groezen, Bas; Meijdam, Lex

    The central question of this paper is how international trade and specialization are affected by different designs of pension schemes and asymmetric demographic changes. In a model with two goods, two countries and two production factors, we find that countries with a relatively large unfunded

  2. Demographic change, international trade and capital flows

    NARCIS (Netherlands)

    Fedotenkov, I.; van Groezen, B.J.A.M.; Meijdam, A.C.

    2014-01-01

    Trade in goods that are not perfect substitutes can considerably change the predictions of standard neoclassical models about the effects of demographic developments. This paper considers a relative decrease in the population size of one country, when countries specialize in the production of

  3. 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.

  4. 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.

  5. 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.

  6. Psychosocial work conditions and work stress in an innovating addiction treatment centre. Consequences for the EFQM Excellence Model

    NARCIS (Netherlands)

    Nabitz, Udo; Jansen, Paul; van der Voet, Sandra; van den Brink, Wim

    2009-01-01

    In the Job Demand Control Model (JDCM) and the EFQM Excellence Model, psychosocial work conditions are regarded as critical factors for the functioning of the personnel and the organisation. In order to gain insight into the role of work conditions for the development of work strain and well-being,

  7. 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.

  8. 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).

  9. 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

  10. 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

  11. 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)

  12. Demographic Transitions and Economic Miracles in Emerging Asia

    OpenAIRE

    David E. Bloom; Jeffrey G. Williamson

    1997-01-01

    The demographic transition a change from high to low rates of mortality and fertility has been more dramatic in East Asia during this century than in any other region or historical period. By introducing demographic variables into an empirical model of economic growth, this essay shows that this transition has contributed substantially to East Asia's so-called economic miracle. The 'miracle' occurred in part because East Asia's demographic transition resulted in its working-age population gro...

  13. A psycho-economic model of ecstasy consumption and related consequences: a multi-site study with community samples.

    Science.gov (United States)

    Abdallah, Arbi Ben; Scheier, Lawrence M; Inciardi, James A; Copeland, Jan; Cottler, Linda B

    2007-01-01

    Becker and Murphy's (1988) theory of rational behavior suggests that economic factors play an influential role in the decision leading to drug consumption and possibly dependence. Psychological models, on the other hand, emphasize internal regulatory cues that motivate drug use and play a contributory role in dependence. Until now, the confluence of both economic and psychological models has not been tested empirically. The present study used latent-variable structural equation modeling (SEM) to examine the influence of both economic (social anomie, unit price, and time spent acquiring drugs) and psychological risk factors (motivation, depression, and sexual risk behaviors) on self-reported ecstasy use. Data were obtained from 612 recreational ecstasy users in the United States and Australia participating in a NIDA-funded epidemiological study examining trends in ecstasy use. The sample was mainly white (61%), male (58%), and young (mean age = 23 yrs [5.25]). All of the hypothesized latent constructs were statistically reliable and correlated in the expected direction. A saturated SEM indicated that monetary and opportunity cost, but not income, significantly predicted ecstasy use. Among the psychological measures, motivational cues were the strongest predictor of both use and dependence. Inclusion of gender, age, race, education, and site variables did not appreciably alter the final model parameters. The implications of incorporating the role of economic factors in shaping a more refined understanding of addiction are discussed. Suggestions for future research and study limitations are also noted.

  14. 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…

  15. Phantom Effects in School Composition Research: Consequences of Failure to Control Biases Due to Measurement Error in Traditional Multilevel Models

    Science.gov (United States)

    Televantou, Ioulia; Marsh, Herbert W.; Kyriakides, Leonidas; Nagengast, Benjamin; Fletcher, John; Malmberg, Lars-Erik

    2015-01-01

    The main objective of this study was to quantify the impact of failing to account for measurement error on school compositional effects. Multilevel structural equation models were incorporated to control for measurement error and/or sampling error. Study 1, a large sample of English primary students in Years 1 and 4, revealed a significantly…

  16. [The demographic doctrines of Plato].

    Science.gov (United States)

    Vilquin, E

    1982-01-01

    Plato has been invoked so often in discussions of population and so many different and contradictory attitudes toward population and demography have been attributed to him that it is necessary to examine his own works and their context in order to understand his true views of the subject. This article briefly examines Plato's demographic thought and its relation to the sociopolitical conditions and intellectual currents of his time and place. The major themes of his demographic work are viewed as outgrowths of the fundamental principles of platonic philosophy and ethics: perfect love, biological and spiritual fertility, procreation as a duty, eugenics, moderation and static equilibrium, the need for demographic legislation, and the justification for and methods of demographic policy. The demographic doctrines espoused in Plato's "Laws" and "The Republic" are then examined. Analysis of Plato's global demographic thought demonstrates how the implementation of perfectly logical means of improving the collective good through measures affecting social organization, legislation, and education resulted in the most totalitarian demographic doctrine ever enunciated. Thus for example, the necessity of harmonizing the ideal of platonic love with the biologic renewal of society led Plato to grant rulers absolute and exclusive power over the family, marriage, sexuality, procreation, and the life and death of infants.

  17. 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.

  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. The association of demographic variables and dietary habits on ...

    African Journals Online (AJOL)

    As the foreign-born populations continue to grow, they experience dietary pattern changes. Dietary changes of immigrants are often associated with weight increase and consequently the risk of non-communicable diseases such as diabetes. This study examined the association of demographic variables and dietary habits ...

  20. Socio-demographic correlates of alcohol consumption among ...

    African Journals Online (AJOL)

    It was hypothesized that the reasons and consequences of alcohol consumption are sport- related and mediated by selected demographic factors and ... of alcohol consumption reported were mainly behaviour offensive to others (42; 32.6%), damaged friendships (40; 29.6%), and poor academic performance (34; 26%).

  1. 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…

  2. Genetic population structuring and demographic history of red ...

    African Journals Online (AJOL)

    Climatic oscillations during the Pleistocene ice ages in the Northwestern Pacific produced great changes in species' geographical distribution and abundance, which could be expected to have genetic consequences in marine fishes. In order to estimate the demographic history and genetic structure of Epinephelus akaara ...

  3. A large 3D physical model: a tool to investigate the consequences of ground movements on the surface structures

    Directory of Open Access Journals (Sweden)

    Hor B.

    2010-06-01

    Full Text Available Soil subsidence of various extend and amplitude can result from the failure of underground cavities, whether natural (for example caused by the dissolution of rocks by underground water flow or man-made (such as mines. The impact of the ground movements on existing structures (houses, buildings, bridges, etc… is generally dramatic. A large small-scale physical model is developed in order to improve our understanding of the behaviour of the building subjected to ground subsidence or the collapse of cavities. We focus on the soil-structure interaction and on the mitigation techniques allowing reducing the vulnerability of the buildings (structures.

  4. Model for transfer of cesium and strontium to domestic animal products as a consequence of accidental deposition on ground

    International Nuclear Information System (INIS)

    Suolanen, V.

    1994-02-01

    In the study the contamination of domestic animal products (milk, beef, pork) and grain is predicted applying a compartment model approach to simulate the dynamic behaviour of radionuclides in the biosphere after an accidental atmospheric deposition. Further, the radionuclide intakes into human body by consumption of the contaminated domestic animal products and the arising internal doses, are studied. The contamination of domestic animal products and grain are predicted by considering three representative deposition cases. The considered deposition timepoints are: spring (1st of May), summer (1st of July) and autumn (1st of September). The nuclides considered are 137 Cs, 134 Cs and 90 Sr. (18 refs., 14 figs., 8 tabs.)

  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. Larval Dispersal of Spodoptera frugiperda Strains on Bt Cotton: A Model for Understanding Resistance Evolution and Consequences for its Management.

    Science.gov (United States)

    Malaquias, José B; Godoy, Wesley A C; Garcia, Adriano G; Ramalho, Francisco de S; Omoto, Celso

    2017-11-23

    High dispersal of Lepidoptera larvae between non-Bt and Bt cotton plants can favour the evolution of insect resistance; however, information on host acceptance of neonates in tropical transgenic crops is scarce. Therefore, the purposes of this study were as follows: (i) to investigate the feeding behaviour of susceptible and Cry1F-resistant strains of Spodoptera frugiperda (J.E. Smith) on Bt and non-Bt cotton (Gossypium hirsutum L.) varieties and (ii) to understand the possible effects of cotton field contamination on the dispersal and infestation capacity of S. frugiperda larvae by using an individual-based model. The main results of this paper are as follows: (1) the highest post-feeding larval dispersal of the Cry1F-resistant strain occurred at an exposure time of 18-24 h; (2) via video tracking assays, we found that the least distance moved was by larvae resistant to Cry1F on non-Bt cotton; and (3) the model indicated differences in mobility capacity between Bt and non-Bt cotton. We conclude that resistant neonates exhibit sedentary behaviour. Our report represents the first findings concerning the fitness cost of larval behaviour traits of S. frugiperda associated with Cry1F resistance in Brazilian populations.

  8. Environmental consequences of a power plant shut-down: a three-dimensional water quality model of Dublin Bay.

    Science.gov (United States)

    Bedri, Zeinab; Bruen, Michael; Dowley, Aodh; Masterson, Bartholomew

    2013-06-15

    A hydro-environmental model is used to investigate the effect of cessation of thermal discharges from a power plant on the bathing water quality of Dublin Bay. Before closing down, cooling water from the plant was mixed with sewage effluent prior to its discharge, creating a warmer, less-saline buoyant pollutant plume that adversely affects the water quality of Dublin Bay. The model, calibrated to data from the period prior to the power-plant shut-down (Scenario1), assessed the water quality following its shut-down under two scenarios; (i) Scenario2: continued abstraction of water to dilute sewage effluents before discharge, and (ii) Scnenario3: sewage effluents are discharged directly into the Estuary. Comparison between scenarios was based on distribution of Escherichia coli (E. coli), a main bathing quality indicator. Scenarios1 and 2, showed almost similar E. coli distribution patterns while Scenario3 displayed significantly higher E. coli concentrations due to the increased stratification caused by the lack of prior dilution. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. 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

  10. Large cities in Poland in face of demographic changes

    Directory of Open Access Journals (Sweden)

    Gołata Elżbieta

    2016-12-01

    Full Text Available The growth of rural population, to the detriment of cities in Poland is caused mainly by agglomeration processes, including suburbanisation. Consequently, intense and sudden changes in demographic structure of large cities and surrounding regions are observed. The paper presents demographic changes in the largest Polish cities. The aim of the study was to verify whether the phenomenon of population aging was more distinct in large cities than in surrounding municipalities. We also aimed to answer the question of how changes in demographic processes should shape the social policy pursued by authorities in large cities. Discussion covers activities rising out of demographic challenges to meet the needs in the field of “services” for children and increasing demand for ventures related to care for the elderly. The analysis includes selected areas of the education, health care and social assistance fields.

  11. Demographic Future of Gorski Kotar

    Directory of Open Access Journals (Sweden)

    Ivan Lajić

    2010-08-01

    Full Text Available Demographic development of Gorski Kotar has largely been a reflection of unfavourable natural-geographic and socio-economic circumstances, which had impelled emigration of the population from this region already by the end of the 19th century, and this process has not stopped till nowadays. The decrease in the total number of inhabitants has been strongly influenced by decades of emigration. Since the 1960s, negative natural movements have significantly contributed to total depopulation. Based on the analysis of negative demographic processes in the Gorski Kotar region, several kinds of demographic projections have been made for the period until 2021. According to these projections, further negative demographic tendencies and additional diminution of the Gorski Kotar population, as well as a negative birth-rate and the erosion of all demographic and economic structures are expected. Population ageing will be a fundamental determinant of future demographic development of the observed area, because every third inhabitant will be more than 60 years old and this points to potential problems in the social and economic development of the region.

  12. Demographic estimation methods for plants with unobservable life-states

    Science.gov (United States)

    Kery, M.; Gregg, K.B.; Schaub, M.

    2005-01-01

    Demographic estimation of vital parameters in plants with an unobservable dormant state is complicated, because time of death is not known. Conventional methods assume that death occurs at a particular time after a plant has last been seen aboveground but the consequences of assuming a particular duration of dormancy have never been tested. Capture-recapture methods do not make assumptions about time of death; however, problems with parameter estimability have not yet been resolved. To date, a critical comparative assessment of these methods is lacking. We analysed data from a 10 year study of Cleistes bifaria, a terrestrial orchid with frequent dormancy, and compared demographic estimates obtained by five varieties of the conventional methods, and two capture-recapture methods. All conventional methods produced spurious unity survival estimates for some years or for some states, and estimates of demographic rates sensitive to the time of death assumption. In contrast, capture-recapture methods are more parsimonious in terms of assumptions, are based on well founded theory and did not produce spurious estimates. In Cleistes, dormant episodes lasted for 1-4 years (mean 1.4, SD 0.74). The capture-recapture models estimated ramet survival rate at 0.86 (SE~ 0.01), ranging from 0.77-0.94 (SEs # 0.1) in anyone year. The average fraction dormant was estimated at 30% (SE 1.5), ranging 16 -47% (SEs # 5.1) in anyone year. Multistate capture-recapture models showed that survival rates were positively related to precipitation in the current year, but transition rates were more strongly related to precipitation in the previous than in the current year, with more ramets going dormant following dry years. Not all capture-recapture models of interest have estimable parameters; for instance, without excavating plants in years when they do not appear aboveground, it is not possible to obtain independent timespecific survival estimates for dormant plants. We introduce rigorous

  13. 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 the National Radiological Protection Board (NRPB), United Kingdom, presented a workshop on methods for assessing the offsite radiological consequences of nuclear accidents. The program consisted of eight sessions. The main conclusions, which were presented in the Round Table Session by the individual Session Chairmen, are summarized. Session topics are as follows: Session I: international developments in the field of accident consequence assessment (ACA); Session II: atmospheric dispersion; Session III: food chain models; Session IV: urban contamination; Session V: demographic and land use data; Session VI: dosimetry, health effects, economic and counter measure models; Session VII: uncertainty analysis; and Session VIII: application of probabilistic consequence models as decision aids

  14. Robustness of an 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 were used in an investigation with the MACCS model of the early health effects associated with a severe accident at a nuclear power station. The following results were obtained in tests to check the robustness of the analysis techniques: two independent Latin hypercube samples produced similar uncertainty and sensitivity analysis results; setting important variables to best-estimate values produced substantial reductions in uncertainty, while setting the less important variables to best-estimate values had little effect on uncertainty; similar sensitivity analysis results were obtained when the original uniform and loguniform distributions assigned to the 34 imprecisely known input variables were changed to left-triangular distributions and then to right-triangular distributions; and analyses with rank-transformed and logarithmically-transformed data produced similar results and substantially outperformed analyses with raw (i.e., untransformed) data

  15. 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...... species for ecotoxicological risk assessment. In the model, individuals were assumed to sense and avoid contaminated habitat with a certain probability that depends on contamination level. Avoidance of contaminated areas thus influenced the individuals’ movement and feeding, their exposure, and in turn...... thus be used as a tool for extrapolating from short-term effects at the individual level to long-term effects at the population level under more realistic conditions. It can thus be used to develop and extrapolate from standard ecotoxicological tests in the laboratory to ecological risk assessments....

  16. Molecular Consequences of the SERPINH1/HSP47 Mutation in the Dachshund Natural Model of Osteogenesis Imperfecta.

    Science.gov (United States)

    Lindert, Uschi; Weis, Mary Ann; Rai, Jyoti; Seeliger, Frank; Hausser, Ingrid; Leeb, Tosso; Eyre, David; Rohrbach, Marianne; Giunta, Cecilia

    2015-07-17

    Osteogenesis imperfecta (OI) is a heritable connective tissue disease characterized by bone fragility and increased risk of fractures. Up to now, mutations in at least 18 genes have been associated with dominant and recessive forms of OI that affect the production or post-translational processing of procollagen or alter bone homeostasis. Among those, SERPINH1 encoding heat shock protein 47 (HSP47), a chaperone exclusive for collagen folding in the ER, was identified to cause a severe form of OI in dachshunds (L326P) as well as in humans (one single case with a L78P mutation). To elucidate the disease mechanism underlying OI in the dog model, we applied a range of biochemical assays to mutant and control skin fibroblasts as well as on bone samples. These experiments revealed that type I collagen synthesized by mutant cells had decreased electrophoretic mobility. Procollagen was retained intracellularly with concomitant dilation of ER cisternae and activation of the ER stress response markers GRP78 and phospho-eIF2α, thus suggesting a defect in procollagen processing. In line with the migration shift detected on SDS-PAGE of cell culture collagen, extracts of bone collagen from the OI dog showed a similar mobility shift, and on tandem mass spectrometry, the chains were post-translationally overmodified. The bone collagen had a higher content of pyridinoline than control dog bone. We conclude that the SERPINH1 mutation in this naturally occurring model of OI impairs how HSP47 acts as a chaperone in the ER. This results in abnormal post-translational modification and cross-linking of the bone collagen. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  17. Measuring the effects of topically applied skin optical clearing agents and modeling the effects and consequences for laser therapies

    Science.gov (United States)

    Verkruysse, Wim; Khan, Misbah; Choi, Bernard; Svaasand, Lars O.; Nelson, J. Stuart

    2005-04-01

    Human skin prepared with an optical clearing agent manifests reduced scattering as a result of de-hydration and refractive index matching. This has potentially large effects for laser therapies of several skin lesions such as port wine stain, hair removal and tattoo removal. With most topically applied clearing agents the clearing effect is limited because they penetrate poorly through the intact superficial skin layer (stratum corneum). Agent application modi other than topical are impractical and have limited the success of optical clearing in laser dermatology. In recent reports, however, a mixture of lipofylic and hydrofylic agents was shown to successfully penetrate through the intact stratum corneum layer which has raised new interest in this field. Immediately after application, the optical clearing effect is superficial and, as the agent diffuses through the skin, reduced scattering is manifested in deeper skin layers. For practical purposes as well as to maximize therapeutic success, it is important to quantify the reduced scattering as well as the trans-cutaneous transport dynamics of the agent. We determined the time and tissue depth resolved effects of optically cleared skin by inserting a microscopic reflector array in the skin. Depth dependent light intensity was measured by quantifying the signal of the reflector array with optical coherence tomography. A 1-dimensional mass diffusion model was used to estimate a trans-cutaneous transport diffusion constant for the clearing agent mixture. The results are used in Monte Carlo modeling to determine the optimal time of laser treatment after topical application of the optical clearing agent.

  18. Daily and 3-hourly variability in global fire emissions and consequences for atmospheric model predictions of carbon monoxide

    Science.gov (United States)

    Mu, M.; Randerson, J. T.; van der Werf, G. R.; Giglio, L.; Kasibhatla, P.; Morton, D.; Collatz, G. J.; Defries, R. S.; Hyer, E. J.; Prins, E. M.; Griffith, D. W. T.; Wunch, D.; Toon, G. C.; Sherlock, V.; Wennberg, P. O.

    2011-12-01

    Attribution of the causes of atmospheric trace gas and aerosol variability often requires the use of high resolution time series of anthropogenic and natural emissions inventories. Here we developed an approach for representing synoptic- and diurnal-scale temporal variability in fire emissions for the Global Fire Emissions Database version 3 (GFED3). We disaggregated monthly GFED3 emissions during 2003-2009 to a daily time step using Moderate Resolution Imaging Spectroradiometer (MODIS)-derived measurements of active fires from Terra and Aqua satellites. In parallel, mean diurnal cycles were constructed from Geostationary Operational Environmental Satellite (GOES) Wildfire Automated Biomass Burning Algorithm (WF_ABBA) active fire observations. Daily variability in fires varied considerably across different biomes, with short but intense periods of daily emissions in boreal ecosystems and lower intensity (but more continuous) periods of burning in savannas. These patterns were consistent with earlier field and modeling work characterizing fire behavior dynamics in different ecosystems. On diurnal timescales, our analysis of the GOES WF_ABBA active fires indicated that fires in savannas, grasslands, and croplands occurred earlier in the day as compared to fires in nearby forests. Comparison with Total Carbon Column Observing Network (TCCON) and Measurements of Pollution in the Troposphere (MOPITT) column CO observations provided evidence that including daily variability in emissions moderately improved atmospheric model simulations, particularly during the fire season and near regions with high levels of biomass burning. The high temporal resolution estimates of fire emissions developed here may ultimately reduce uncertainties related to fire contributions to atmospheric trace gases and aerosols. Important future directions include reconciling top-down and bottom up estimates of fire radiative power and integrating burned area and active fire time series from

  19. Daily and 3-hourly Variability in Global Fire Emissions and Consequences for Atmospheric Model Predictions of Carbon Monoxide

    Science.gov (United States)

    Mu, M.; Randerson, J. T.; vanderWerf, G. R.; Giglio, L.; Kasibhatla, P.; Morton, D.; Collatz, G. J.; DeFries, R. S.; Hyer, E. J.; Prins, E. M.; hide

    2011-01-01

    Attribution of the causes of atmospheric trace gas and aerosol variability often requires the use of high resolution time series of anthropogenic and natural emissions inventories. Here we developed an approach for representing synoptic- and diurnal-scale temporal variability in fire emissions for the Global Fire Emissions Database version 3 (GFED3). We disaggregated monthly GFED3 emissions during 2003.2009 to a daily time step using Moderate Resolution Imaging Spectroradiometer (MODIS) ]derived measurements of active fires from Terra and Aqua satellites. In parallel, mean diurnal cycles were constructed from Geostationary Operational Environmental Satellite (GOES) Wildfire Automated Biomass Burning Algorithm (WF_ABBA) active fire observations. Daily variability in fires varied considerably across different biomes, with short but intense periods of daily emissions in boreal ecosystems and lower intensity (but more continuous) periods of burning in savannas. These patterns were consistent with earlier field and modeling work characterizing fire behavior dynamics in different ecosystems. On diurnal timescales, our analysis of the GOES WF_ABBA active fires indicated that fires in savannas, grasslands, and croplands occurred earlier in the day as compared to fires in nearby forests. Comparison with Total Carbon Column Observing Network (TCCON) and Measurements of Pollution in the Troposphere (MOPITT) column CO observations provided evidence that including daily variability in emissions moderately improved atmospheric model simulations, particularly during the fire season and near regions with high levels of biomass burning. The high temporal resolution estimates of fire emissions developed here may ultimately reduce uncertainties related to fire contributions to atmospheric trace gases and aerosols. Important future directions include reconciling top ]down and bottom up estimates of fire radiative power and integrating burned area and active fire time series from

  20. The conditioned place preference test for assessing welfare consequences and potential refinements in a mouse bladder cancer model.

    Directory of Open Access Journals (Sweden)

    John V Roughan

    Full Text Available Most pre-clinical analgesic efficacy assays still involve nociceptive testing in rodents. This is despite concerns as to the relevance of these tests for evaluating the pain-preventative properties of drugs. More appropriate methods would target pain rather than nociception, but these are currently not available, so it remains unknown whether animal pain equates to the negatively affective and subjective/emotional state it causes in humans. Mouse cancer models are common despite the likelihood of substantial pain. We used Conditioned Place Preference (CPP testing, assessments of thermal hyperalgesia and behaviour to determine the likelihood that MBT-2 bladder cancer impacts negatively on mouse welfare, such as by causing pain. There was no CPP to saline, but morphine preference in tumour bearing mice exceeded that seen in tumour-free controls. This occurred up to 10 days before the study end-point alongside reduced body weight, development of hyperalgesia and behaviour changes. These effects indicated mice experienced a negative welfare state caused by malaise (if not pain before euthanasia. Due to the complexity of the assessments needed to demonstrate this, it is unlikely that this approach could be used for routine welfare assessment on a study-by-study basis. However, our results show mice in sufficiently similar studies are likely to benefit from more intensive severity assessment and re-evaluation of end-points with a view to implementing appropriate refinements. In this particular case, a refinement would have been to have euthanased mice at least 7 days earlier or possibly by provision of end-stage pain relief. CPP testing was found to be a helpful method to investigate the responses of mice to analgesics, possibly on a subjective level. These findings and those of other recent studies show it could be a valuable method of screening candidate analgesics for efficacy against cancer pain and possibly other pain or disease models.

  1. Critical analysis of accident scenario and consequences modelling applied to light-water reactor power plants for accident categories beyond the design basis accident (DBA)

    International Nuclear Information System (INIS)

    Brofferio, C.; Cagnetti, P.; Ferrara, V.; Manilia, E.; Pietrangeli, G.; Sennis, C.

    1985-01-01

    A critical analysis and sensitivity study of the modelling of accident scenarios and environmental consequences are presented, for light-water reactor accident categories beyond the standard design-basis-accident category. The first chapter, on ''source term'' deals with the release of fission products from a damaged core inventory and their migration within the primary circuit and the reactor containment. Particular attention is given to the influence of engineering safeguards intervention and of the chemical forms of the released fission products. The second chapter deals with their release to the atmosphere, transport and wet or dry deposition, outlining relevant partial effects and confronting short-duration or prolonged releases. The third chapter presents a variability analysis, for environmental contamination levels, for two extreme hypothetical scenarios, evidencing the importance of plume rise. A numerical plume rise model is outlined

  2. The Impact of Extrinsic Demographic Factors on Cantonese Speech Acquisition

    Science.gov (United States)

    To, Carol K. S.; Cheung, Pamela S. P.; McLeod, Sharynne

    2013-01-01

    This study modeled the associations between extrinsic demographic factors and children's speech acquisition in Hong Kong Cantonese. The speech of 937 Cantonese-speaking children aged 2;4 to 6;7 in Hong Kong was assessed using a standardized speech test. Demographic information regarding household income, paternal education, maternal education,…

  3. Economic consequences of biological variation

    DEFF Research Database (Denmark)

    Otto, Lars

    2005-01-01

    We present an economic decision support model, based on a Bayesian network, for Mycoplasma infection in slaughter swine production. The model describes the various risk factors for Mycoplasma infection and their interactions. This leads to a stochastic determination of the consequences of product......We present an economic decision support model, based on a Bayesian network, for Mycoplasma infection in slaughter swine production. The model describes the various risk factors for Mycoplasma infection and their interactions. This leads to a stochastic determination of the consequences...... of productivity factors, and this again results in stochastic economic consequences when changing the risk factors or engaging in control arrangements. We use the model to calculate how estimated prevalence and level of Mycoplasma changes when we gather evidence from various veterinarian examinations, and we show...

  4. Heterogeneity of demand responses in modelling the distributional consequences of tradable carbon permits in the road transport sector

    International Nuclear Information System (INIS)

    Wadud, Zia; Noland, Robert B.; Graham, Daniel J.

    2007-01-01

    Personal road transport sector is one of the largest and fastest growing sources of CO 2 emissions. This paper investigates a tradable permit policy for mitigating carbon emissions from personal road transport and discusses various issues of permit allocation. As tradable permits will effectively raise the price of fuel, the policy has important distributional implications. The distribution of burden depends on permit allocation strategies and on the consumer response to an increase in price. The behavioural response may vary among different segments of the population depending on their travel needs, which in turn are contingent upon their income, location of residence and other factors. Consumer Expenditure Survey micro dataset from 1997 to 2002 has been used to econometrically model the possible variation of price elasticity for different socio-economic groups in the USA. Results indicate that the response of gasoline demand to a change in price does depend on income level or location of the household. Distributional impacts of the tradable permit policy are then evaluated using the micro dataset for year 2002. In this regard, different permit allocation schemes are considered in the analysis. Impacts on households owning a vehicle and households with no vehicles have been evaluated as well

  5. Daily and Hourly Variability in Global Fire Emissions and Consequences for Atmospheric Model Predictions of Carbon Monoxide

    Science.gov (United States)

    Mu, M.; Randerson, J. T.; van der Werf, G. R.; Giglio, L.; Kasibhatla, P.; Morton, D.; Collatz, G. J.; DeFries, R. S.; Hyer, E. J.; Prins, E. M.; hide

    2011-01-01

    Attribution of the causes of atmospheric trace gas and aerosol variability often requires the use of high resolution time series of anthropogenic and natural emissions inventories. Here we developed an approach for representing synoptic- and diurnal-scale temporal variability in fire emissions for the Global Fire Emissions Database version 3 (GFED3). We distributed monthly GFED3 emissions during 2003-2009 on a daily time step using Moderate Resolution Imaging Spectroradiometer (MODIS)-derived measurements of active fires from Terra and Aqua satellites. In parallel, mean diurnal cycles were constructed from Geostationary Operational Environmental Satellite (GOES) active fire observations. We found that patterns of daily variability in fires varied considerably across different biomes, with short but intense periods of daily emissions in boreal ecosystems and lower intensity (but more continuous) periods of bunting in savannas. On diurnal timescales, our analysis of the GOES active fires indicated that fires in savannas, grasslands, and croplands occurred earlier in the day as compared to fires in nearby forests. Comparison with Total Carbon Column Observing Network (TCCON) and Measurements of Pollution in the Troposphere (MOPITT) column CO observations provided evidence that including daily variability in emissions moderately improved atmospheric model simulations, particularly during the fire season and near regions with high levels of biomass burning. The high temporal resolution estimates of fire emissions developed here may ultimately reduce uncertainties related to fire contributions to atmospheric trace gases and aerosols. Important future directions include reconciling top-down and bottom up estimates of fire radiative power and integrating burned area and active fire time series from multiple satellite sensors to improve daily emissions estimates.

  6. SU-E-T-547: Modeling Biological Response to Proton Irradiation and Evaluating Its Potential Clinical Consequences

    Energy Technology Data Exchange (ETDEWEB)

    Taleei, R; Peeler, C; Guan, F; Patel, D; Titt, U; Mirkovic, D; Grosshans, D; Mohan, R [Departments of Radiation Physics and Radiation Oncology, The University of Texas, MD Anderson Cancer Center, Houston, TX (United States)

    2015-06-15

    Purpose: In addition to physical uncertainties, proton therapy may also be associated with biologic uncertainties. Currently a generic RBE value of 1.1 is used for treatment planning. In this work the effects of variable RBE, in comparison to a fixed RBE, were evaluated by calculating the effective dose for proton treatments. Methods: The repair misrepair fixation (RMF) model was used to calculate variable proton RBEs. The RBE weighted spread-out Bragg peak (SOBP) dose in water phantom was calculated using Monte Carlo simulation and compared to 1.1 weighted SOBP dose. A head and neck proton treatment was used to evaluate the potential effects, by comparing the head and neck treatment plan computed with a commercial treatment planning system that incorporates fixed RBE of 1.1 and a Monte Carlo treatment planning system that incorporates variable RBE. Results: RBE calculations along the depth of SOBP showed that the RBE at the entrance is approximately 1 and reaches 1.1 near the center of the SOBP. However, in distal regions the RBE rises to higher values (up to 3.5 depending on the cell type). Comparison of commercial treatment plans using a fixed RBE of 1.1 and Monte Carlo using variable RBE showed noticeable differences in the effective dose distributions. Conclusion: The comparison of the treatment planning with fixed and variable RBE shows that using commercial treatment planning systems that incorporate fixed RBE (1.1) could Result in overestimation of the effective dose to part of head and neck target volumes, while underestimating the effective dose to the normal tissue beyond the tumor. The accurate variable RBE as a function of proton beam energy in patient should be incorporated in treatment planning to improve the accuracy of effective dose calculation.

  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. The Importance of Considering the Temporal Distribution of Climate Variables for Ecological-Economic Modeling to Calculate the Consequences of Climate Change for Agriculture

    Science.gov (United States)

    Plegnière, Sabrina; Casper, Markus; Hecker, Benjamin; Müller-Fürstenberger, Georg

    2014-05-01

    The basis of many models to calculate and assess climate change and its consequences are annual means of temperature and precipitation. This method leads to many uncertainties especially at the regional or local level: the results are not realistic or too coarse. Particularly in agriculture, single events and the distribution of precipitation and temperature during the growing season have enormous influences on plant growth. Therefore, the temporal distribution of climate variables should not be ignored. To reach this goal, a high-resolution ecological-economic model was developed which combines a complex plant growth model (STICS) and an economic model. In this context, input data of the plant growth model are daily climate values for a specific climate station calculated by the statistical climate model (WETTREG). The economic model is deduced from the results of the plant growth model STICS. The chosen plant is corn because corn is often cultivated and used in many different ways. First of all, a sensitivity analysis showed that the plant growth model STICS is suitable to calculate the influences of different cultivation methods and climate on plant growth or yield as well as on soil fertility, e.g. by nitrate leaching, in a realistic way. Additional simulations helped to assess a production function that is the key element of the economic model. Thereby the problems when using mean values of temperature and precipitation in order to compute a production function by linear regression are pointed out. Several examples show why a linear regression to assess a production function based on mean climate values or smoothed natural distribution leads to imperfect results and why it is not possible to deduce a unique climate factor in the production function. One solution for this problem is the additional consideration of stress indices that show the impairment of plants by water or nitrate shortage. Thus, the resulting model takes into account not only the ecological

  9. [Demographic research in Togo. Evaluation of change and prospects].

    Science.gov (United States)

    Nomenyo, A

    1986-01-01

    It is only since the independance of Togo, in 1958, and after 3 General Census, (1958-59, 1970, 1981), followed immediately by post-census surveys, that a solid basis of statistical data has been available for demographic research. But it is only after 1970, with the creation of the Benin University, and its Demographic Research Unit, the arrival of researchers at the ORSTOM Center of Lome, and of the demographers trained at the IFORD and IDP, that real demographic research has existed. Since then, the ORSTOM has conducted a study on the dynamics of population (fertility, migration, nuptiality, mortality) and its socioeconomic consequences on the agricultural economy of the Plateau Region (1975-1979). It is currently conducting a study in North Togo, comparing demographic data (nuptiality, fertility, infant mortality, family structure) with socioeconomic data (system of land property, women's activity, wives' status in polygamic families), for a better understanding of the influence of demographic reproduction on global social reproduction. The Demographic Research Unit led several studies on fertility in Southeast Togo and Lome. Several other surveys by the department of statistics and the IFORD, by the INRS, as well as student these from diverse schools of Benin University, are studying demo-geography, demo-economy, and demo-sociology. Still, the main problems are the bad quality of the data on fertility and mortality, and the inconsistancy of civil registration. But the interest of the present administration for demographic information may lead to the creation of a "Population Unit" assisting the government, to the definition of a status for researchers, and to the participation of Togo in the new program of Demographic and Health Surveys planned for 35 countries by the Westinghouse Institute for Resource Development.

  10. 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.

  11. 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.

  12. 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

  13. Alcohol use and alcohol-related consequences: associations with emotion regulation difficulties.

    Science.gov (United States)

    Dvorak, Robert D; Sargent, Emily M; Kilwein, Tess M; Stevenson, Brittany L; Kuvaas, Nicholas J; Williams, Thomas J

    2014-03-01

    Understanding factors associated with alcohol-related consequences is an important area of research. Emotional functioning has been associated with alcohol-related consequences but there is less research examining a comprehensive underlying model of emotional regulation. The Difficulties in Emotion Regulation Scale (DERS) is a recent measure developed to assess six facets of emotion regulation difficulties that contribute to overall emotional functioning. The current study examines associations between these six facets of emotion regulation difficulties and problematic alcohol use. Participants (n = 1758 college students) were recruited as part of a larger study and were asked to complete online questionnaires assessing demographics, alcohol use and problems, and emotion regulation difficulties. Negative binomial hurdle models for alcohol use and alcohol-related consequences were estimated. Impulse control difficulties were positively related to the number of drinks consumed during the week among active drinkers. Non-acceptance of emotional responses, impulse control difficulties, lack of emotional clarity, and difficulties engaging in goal-directed behavior were all positively associated with number of consequences endorsed. Difficulty engaging in goal-directed behavior was also positively associated with the likelihood of experiencing any alcohol-related consequences. The findings support previous research indicating that emotion-regulation difficulties are broadly associated with alcohol-related consequences. Results suggest exposure and/or mindfulness based prevention/interventions with emotion focused psychoeducation may offer one path to reducing alcohol-related consequences among college students.

  14. Contemporary demographic changes of the Rasina district

    Directory of Open Access Journals (Sweden)

    Stričević Ljiljana

    2016-01-01

    Full Text Available Rasina District is faced with serious demographic problems at the beginning of the twenty-first century which are the consequence of long-term economic and social changes both in this area and the country as a whole. The basic problem is insufficient population regeneration, which further leads to other negative processes. One of the most important problems of Rasina District is the ageing of population, i.e., a drop in young population and a significant rise in old population. Therefore, the population of Rasina District is already in the critical phase of demographic aging. Such age structure influences further economic development of this area at large. The decrease in young population, which is the carrier of future reproduction and regeneration of the population of this area, is evident. So as to stop or decelerate these processes, it is necessary to improve life conditions and ensure certain economic standard. Otherwise, these processes will not be stopped; they will be all the more intensified.

  15. Spanish flu, Asian flu, Hong Kong flu, and seasonal influenza in Japan under social and demographic influence: review and analysis using the two-population model.

    Science.gov (United States)

    Yoshikura, Hiroshi

    2014-01-01

    When cumulative numbers of patients (X) and deaths (Y) associated with an influenza epidemic are plotted using the log-log scale, the plots fall on an ascending straight line generally expressed as logY = k(logX - logN0). For the 2009 H1N1 influenza pandemic, the slope k was ~0.6 for Mexico and ~2 for other countries. The two-population model was proposed to explain this phenomenon (Yoshikura H. Jpn J Infect Dis. 2012;65:279-88; Yoshikura H. Jpn J Infect Dis. 2009;62:411-2; and Yoshikura H. Jpn J Infect Dis. 2009;62:482-4). The current article reviews and analyzes previous influenza epidemics in Japan to examine whether the two-population model is applicable to them. The slope k was found to be ~2 for the Spanish flu during 1918-1920 and the Asian flu during 1957-1958, and ~1 for the Hong Kong flu and seasonal influenza prior to 1960-1961; however, k was ~0.6 for seasonal influenza after 1960-1961. This transition of the slope k of seasonal influenza plots from ~1 to ~0.6 corresponded to the shift in influenza mortality toward the older age groups and a drastic reduction in infant mortality rates due to improvements in the standard of living during the 1950s and 1960s. All the above observations could be well explained by reconstitution of the influenza epidemic based on the two-population model.

  16. Population Composition, Migration and Inequality: The Influence of Demographic Changes on Disaster Risk and Vulnerability

    Science.gov (United States)

    Donner, William; Rodriguez, Havidan

    2008-01-01

    The changing demographic landscape of the United States calls for a reassessment of the societal impacts and consequences of so called "natural" and technological disasters. An increasing trend towards greater demographic and socio-economic diversity (in part due to high rates of international immigration), combined with mounting…

  17. Logistics Dynamics and Demographic Change

    NARCIS (Netherlands)

    Klumpp, Matthias; Abidi, Hella; Bioly, Sascha; Buchkremer, Rüdiger; Ebener, Stefan; Sandhaus, Gregor; Freitag, Michael; Kotzab, Herbert; Pannek, Jürgen

    2016-01-01

    Change and dynamics in logistics are interestingly driven at the same time by external as well as internal forces. This contribution outlines a big data literature review methodology to overview recognizable external changes and analyzes the interaction of one major trend—demographic change—further

  18. Changing Demographics: Challenges for Educators.

    Science.gov (United States)

    Williams, Betty Fry

    1992-01-01

    This paper identifies demographic changes in the areas of poverty, single-parent families, teenage pregnancy, and educational achievement, with emphasis on increased vulnerability of minority populations. It also notes related challenges to the educational system in personnel recruitment and preparation, effective delivery of educational services…

  19. The demographic situation in Cambodia.

    Science.gov (United States)

    Huguet, J W

    1991-12-01

    The demographic situation in Cambodia is described. Various estimates made by official bodies are used, since very little statistical data exists for the country. Estimates are provided for age and sex distribution, spatial distribution, the disabled population, widowed and separated women, numbers of displaced persons by province, and number of returnees expected from camps in neighboring Thailand.

  20. Are Demographics the Nation's Destiny?

    Science.gov (United States)

    Glass, Gene V.

    2008-01-01

    In this article, the author discusses the demographic trends affecting America's public schools. As an expert on empirical evaluation of education, the author believes the major debates over vouchers, charter schools, bilingual education, and other issues are not really about preparing the next generation to compete with China or India, or about…

  1. Seismic Consequence Abstraction

    International Nuclear Information System (INIS)

    Gross, M.

    2004-01-01

    The primary purpose of this model report is to develop abstractions for the response of engineered barrier system (EBS) components to seismic hazards at a geologic repository at Yucca Mountain, Nevada, and to define the methodology for using these abstractions in a seismic scenario class for the Total System Performance Assessment - License Application (TSPA-LA). A secondary purpose of this model report is to provide information for criticality studies related to seismic hazards. The seismic hazards addressed herein are vibratory ground motion, fault displacement, and rockfall due to ground motion. The EBS components are the drip shield, the waste package, and the fuel cladding. The requirements for development of the abstractions and the associated algorithms for the seismic scenario class are defined in ''Technical Work Plan For: Regulatory Integration Modeling of Drift Degradation, Waste Package and Drip Shield Vibratory Motion and Seismic Consequences'' (BSC 2004 [DIRS 171520]). The development of these abstractions will provide a more complete representation of flow into and transport from the EBS under disruptive events. The results from this development will also address portions of integrated subissue ENG2, Mechanical Disruption of Engineered Barriers, including the acceptance criteria for this subissue defined in Section 2.2.1.3.2.3 of the ''Yucca Mountain Review Plan, Final Report'' (NRC 2003 [DIRS 163274])

  2. Seismic Consequence Abstraction

    Energy Technology Data Exchange (ETDEWEB)

    M. Gross

    2004-10-25

    The primary purpose of this model report is to develop abstractions for the response of engineered barrier system (EBS) components to seismic hazards at a geologic repository at Yucca Mountain, Nevada, and to define the methodology for using these abstractions in a seismic scenario class for the Total System Performance Assessment - License Application (TSPA-LA). A secondary purpose of this model report is to provide information for criticality studies related to seismic hazards. The seismic hazards addressed herein are vibratory ground motion, fault displacement, and rockfall due to ground motion. The EBS components are the drip shield, the waste package, and the fuel cladding. The requirements for development of the abstractions and the associated algorithms for the seismic scenario class are defined in ''Technical Work Plan For: Regulatory Integration Modeling of Drift Degradation, Waste Package and Drip Shield Vibratory Motion and Seismic Consequences'' (BSC 2004 [DIRS 171520]). The development of these abstractions will provide a more complete representation of flow into and transport from the EBS under disruptive events. The results from this development will also address portions of integrated subissue ENG2, Mechanical Disruption of Engineered Barriers, including the acceptance criteria for this subissue defined in Section 2.2.1.3.2.3 of the ''Yucca Mountain Review Plan, Final Report'' (NRC 2003 [DIRS 163274]).

  3. Health effects models for nuclear power plant accident consequence analysis: Low LET radiation: Part 2, Scientific bases for health effects models

    Energy Technology Data Exchange (ETDEWEB)

    Abrahamson, S.; Bender, M.; Book, S.; Buncher, C.; Denniston, C.; Gilbert, E.; Hahn, F.; Hertzberg, V.; Maxon, H.; Scott, B.

    1989-05-01

    This report provides 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. Two-parameter Weibull hazard functions are recommended for estimating 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 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 provided. For most cancers, both incidence and mortality are addressed. Linear and linear-quadratic models are also recommended for assessing genetic risks. Five classes of genetic disease -- dominant, x-linked, aneuploidy, unbalanced translocation and multifactorial diseases --are considered. In addition, the impact of radiation-induced genetic damage on the incidence of peri-implantation embryo losses is discussed. The uncertainty in modeling radiological health risks is addressed by providing central, upper, and lower estimates of all model parameters. Data are provided which should enable analysts to consider the timing and severity of each type of health risk. 22 refs., 14 figs., 51 tabs.

  4. Health effects models for nuclear power plant accident consequence analysis: Low LET radiation: Part 2, Scientific bases for health effects models

    International Nuclear Information System (INIS)

    Abrahamson, S.; Bender, M.; Book, S.

    1989-05-01

    This report provides 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. Two-parameter Weibull hazard functions are recommended for estimating 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 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 provided. For most cancers, both incidence and mortality are addressed. Linear and linear-quadratic models are also recommended for assessing genetic risks. Five classes of genetic disease -- dominant, x-linked, aneuploidy, unbalanced translocation and multifactorial diseases --are considered. In addition, the impact of radiation-induced genetic damage on the incidence of peri-implantation embryo losses is discussed. The uncertainty in modeling radiological health risks is addressed by providing central, upper, and lower estimates of all model parameters. Data are provided which should enable analysts to consider the timing and severity of each type of health risk. 22 refs., 14 figs., 51 tabs

  5. Modeling the Effects of Duration and Size of the Control Zones on the Consequences of a Hypothetical African Swine Fever Epidemic in Denmark.

    Science.gov (United States)

    Halasa, Tariq; Bøtner, Anette; Mortensen, Sten; Christensen, Hanne; Wulff, Sisse Birk; Boklund, Anette

    2018-01-01

    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 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 the duration of the protection and surveillance zones were reduced from 50 and 45 days to 35 and 25 days or to 35 and 25 days, respectively. These scenarios were run with or without enlargement of the surveillance zone around detected herds from 10 to 15 km. The scenarios were also run with only clinical 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 it may result in a substantial reduction in the total economic losses. In addition, the model predicts that increasing the size of the surveillance zone from 10 to 15 km may reduce both the epidemic duration and the total economic losses, in case of large epidemics. The ranking of the control strategies by the total costs of the epidemics was not influenced by changes of input parameters in the sensitivity analyses.

  6. Ecological and Socio-Economic Modeling of Consequences of Biological Management Scenarios Implementation in Integrated Watershed Management (Case Study: Simindasht Catchment

    Directory of Open Access Journals (Sweden)

    A. R. Keshtkar

    2016-09-01

    Full Text Available Integrated watershed management is considered as a new principle for development planning and management of water and soil resources emphasizing on socio-economic characteristics of the region to sustainable livelihoods without vulnerability for plants and the residents of an area. This research, in line with the objectives of integrated management, has been carried out for modelling and evaluating the effects of ecological, socio-economic consequences resulting from the implementation of the proposed management plans on the vegetation changes with a focus on the problems in Simindasht catchment, located in Semnan and Tehran Provinces. After standardization of indices by distance method and weighing them, the scenarios were prioritized using multi-criteria decision-making technique. Trade-off analysis of the results indicates that in the integrated management of Simindasht catchment more than one single management solution, covering all aspects of the system can be recommended in different weighting approaches. The approach used herein, considering the results of different models and comparing the results, is an efficient tool to represent the watershed system as a whole and to facilitate decision making for integrated watershed management.

  7. The applicability of CFD to simulate and study the mixing process and the thermo-hydraulic consequences of a main steam line break in PWR model

    Directory of Open Access Journals (Sweden)

    Farkas Istvan

    2017-01-01

    Full Text Available This paper focuses on the validation and applicability of CFD to simulate and analyze the thermo-hydraulic consequences of a main steam line break. Extensive validation data come from experiments performed using the Rossendorf coolant mixing model facility. For the calculation, the range of 9 to 12 million hexahe¬dral cells was constructed to capture all details in the interrogation domain in the system. The analysis was performed by running a time-dependent calculation, Detailed analyses were made at different cross-sections in the system to evaluate not only the value of the maximum and minimum temperature, but also the loca¬tion and the time at which it occurs during the transient which is considered to be indicator for the quality of mixing in the system. CFD and experimental results were qualitatively compared; mixing in the cold legs with emergency core cooling systems was overestimated. This could be explained by the sensitivity to the bound¬ary conditions. In the downcomer, the experiments displayed higher mixing: by our assumption this related to the dense measurement grid (they were not modelled. The temperature distribution in the core inlet plane agreed with the measurement results. Minor deviations were seen in the quantitative comparisons: the maximum temperature difference was 2ºC.

  8. Assessment of the phenology impact on SVAT modelling through a crop growth model over a Mediterranean crop site : Consequences on the water balance under climate change conditions.

    Science.gov (United States)

    Moulin, S.; Garrigues, S.; Olioso, A.; Ruget, F.; Desfonds, V.; Bertrand, N.; Lecharpentier, P.; Ripoche, D.; Launay, M.; Brisson, N.

    2012-04-01

    In the coming years, water resources and vegetation production of Mediterranean areas will be drastically affected by climate changes as well as intense and rapid changes in the land use. The impact of climate and land-use changes on water balance and vegetation production can be analysed and predicted through land surface models, provided that the uncertainties associated to these models and to the data used to run them are evaluated. Vegetation phenology is generally poorly taken into account in land surface models and may be a substantial source of uncertainties for global change scenario studies. In this paper, we discuss the improvement obtained in Soil Vegetation Atmosphere Transfer (SVAT) modelling by taking into account the phenology using a crop growth model, focusing on the water budget, over a Mediterranean crop site. The STICS model (Brisson et al, 1998) is used to simulate crop processes (growth and development, taking into account water and nitrogen exchanges between the environment and the crop). STICS describes the vegetation phenology very accurately and was validated for many types of crop and various pedoclimatic conditions. The SVAT model being analyzed is the a-gs version (Calvet et al., 1998) of the ISBA model (Noilhan et al, 1989), which simulates the photosynthesis and calculates the plant biomass and the Leaf Area Index (LAI) using a simple growth model. In STICS, the phenology is driven by the sum of daily air temperatures, which is quite realistic, while in ISBA, the phenology is driven by the plant carbon assimilation. Measurements (vegetation characteristics, soil properties, agricultural practises, energy and water balance) performed in the lower Rhone valley experimental area (Avignon, France) are used as well as long series of climatic data (past records and future simulations). In a first step, by running STICS and ISBA for maize and wheat crops with long series of climatic data, including future scenarios of climate (CLIMATOR

  9. Cassini Spacecraft Uncertainty Analysis Data and Methodology Review and Update/Volume 1: Updated Parameter Uncertainty Models for the Consequence Analysis

    Energy Technology Data Exchange (ETDEWEB)

    WHEELER, TIMOTHY A.; WYSS, GREGORY D.; HARPER, FREDERICK T.

    2000-11-01

    Uncertainty distributions for specific parameters of the Cassini General Purpose Heat Source Radioisotope Thermoelectric Generator (GPHS-RTG) Final Safety Analysis Report consequence risk analysis were revised and updated. The revisions and updates were done for all consequence parameters for which relevant information exists from the joint project on Probabilistic Accident Consequence Uncertainty Analysis by the United States Nuclear Regulatory Commission and the Commission of European Communities.

  10. Using Twitter data for demographic research

    Directory of Open Access Journals (Sweden)

    Dilek Yildiz

    2017-11-01

    Full Text Available Background: Social media data is a promising source of social science data. However, deriving the demographic characteristics of users and dealing with the nonrandom, nonrepresentative populations from which they are drawn represent challenges for social scientists. Objective: Given the growing use of social media data in social science research, this paper asks two questions: 1 To what extent are findings obtained with social media data generalizable to broader populations, and 2 what is the best practice for estimating demographic information from Twitter data? Methods: Our analyses use information gathered from 979,992 geo-located Tweets sent by 22,356 unique users in South East England between 23 June and 4 July 2014. We estimate demographic characteristics of the Twitter users with the crowd-sourcing platform CrowdFlower and the image-recognition software Face++. To evaluate bias in the data, we run a series of log-linear models with offsets and calibrate the nonrepresentative sample of Twitter users with mid-year population estimates for South East England. Results: CrowdFlower proves to be more accurate than Face++ for the measurement of age, whereas both tools are highly reliable for measuring the sex of Twitter users. The calibration exercise allows bias correction in the age-, sex-, and location-specific population counts obtained from the Twitter population by augmenting Twitter data with mid-year population estimates. Contribution: The paper proposes best practices for estimating Twitter users' basic demographic characteristics and a calibration method to address the selection bias in the Twitter population, allowing researchers to generalize findings based on Twitter to the general population.

  11. Consequences of cell-to-cell P-glycoprotein transfer on acquired multidrug resistance in breast cancer: a cell population dynamics model

    Directory of Open Access Journals (Sweden)

    Webb Glenn

    2011-01-01

    Full Text Available Abstract Background Cancer is a proliferation disease affecting a genetically unstable cell population, in which molecular alterations can be somatically inherited by genetic, epigenetic or extragenetic transmission processes, leading to a cooperation of neoplastic cells within tumoural tissue. The efflux protein P-glycoprotein (P-gp is overexpressed in many cancer cells and has known capacity to confer multidrug resistance to cytotoxic therapies. Recently, cell-to-cell P-gp transfers have been shown. Herein, we combine experimental evidence and a mathematical model to examine the consequences of an intercellular P-gp trafficking in the extragenetic transfer of multidrug resistance from resistant to sensitive cell subpopulations. Methodology and Principal Findings We report cell-to-cell transfers of functional P-gp in co-cultures of a P-gp overexpressing human breast cancer MCF-7 cell variant, selected for its resistance towards doxorubicin, with the parental sensitive cell line. We found that P-gp as well as efflux activity distribution are progressively reorganized over time in co-cultures analyzed by flow cytometry. A mathematical model based on a Boltzmann type integro-partial differential equation structured by a continuum variable corresponding to P-gp activity describes the cell populations in co-culture. The mathematical model elucidates the population elements in the experimental data, specifically, the initial proportions, the proliferative growth rates, and the transfer rates of P-gp in the sensitive and resistant subpopulations. Conclusions We confirmed cell-to-cell transfer of functional P-gp. The transfer process depends on the gradient of P-gp expression in the donor-recipient cell interactions, as they evolve over time. Extragenetically acquired drug resistance is an additional aptitude of neoplastic cells which has implications in the diagnostic value of P-gp expression and in the design of chemotherapy regimens. Reviewers This

  12. Introduction to the Special Collection on Finding Work-Life Balance: History, Determinants, and Consequences of New Bread-Winning Models in the Industrialized World

    Directory of Open Access Journals (Sweden)

    Trude Lappegård

    2017-09-01

    Full Text Available Background: A wide range of new models for breadwinning and caregiving is emerging in the industrialized world. The massive increase in women's labor force participation is bringing many women into the public sphere of men and many men into greater engagement with the private sphere. These are the two halves o