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Aplicação da escala de qualidade de vida em crianças de 07 a 12 anos praticantes de atividade fisica em academia e suas relações com a aptidão fisica; Implementation of the quality of life scale for children between 07 and 12 years of age practicing physical activity in the gym

Evandro Murer
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 22/02/2008 PT
Relevância na Pesquisa
35.81%
O objetivo deste estudo foi avaliar a qualidade de vida de crianças praticantes de atividade física em academia através da Escala de Qualidade de Vida ? AUQEI ? (AUTOQUESTIONNAIRE QUALITÉ DE VIE ENFANT IMAGE), específica para crianças de 04 a 12 anos, e verificar a existência de correlação dos resultados obtidos com a aptidão física. Foram estudadas 50 crianças, sendo 30 meninas e 20 meninos, nas faixas etárias dos 07 aos 12 anos de idade, que freqüentavam a academia de 02 a 05 vezes por semana. O escore para as médias da escala foi calculado e o resultado padronizado em um valor de 0 a 100. A consistência da escala AUQEI assim como seus domínios foram medidas através do Alpha de Cronbach. Foram avaliados também os domínios do AUQEI em relação a variável gênero, índice de massa corporal (IMC), flexibilidade, porcentagem de gordura no corpo e freqüência que utiliza a academia. Para tal, foram mensuradas as variáveis antropométricas de peso, estatura e a as de composição corporal através do protocolo de Deurenberg (04 dobras) e a flexibilidade através do teste de sentar e alcançar (TSA - Banco de Wells). Foi verificado também o estado nutricional através do índice de massa corporal - IMC (peso/estatura2). Para classificação dos dados...

Rendas vitalícias sobre casais

Serrano, Ana Sofia Alves
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Dissertação de Mestrado
Publicado em //2013 POR
Relevância na Pesquisa
35.8%
Dissertação de mestrado em Economia Monetária, Bancária e Financeira; A duração da vida humana é cada vez mais longa. O aumento sistemático da longevidade é um risco enfrentado pela Segurança Social, mas também pelas seguradoras do Ramo Vida. As seguradoras oferecem proteção contra o risco de longevidade através da oferta de rendas sobre a vida humana ou outros produtos em que estas sejam parte integrante. Nesta dissertação efetua-se um estudo, sob o ponto de vista atuarial, das rendas sobre a vida humana, dando-se especial relevo às rendas sobre casais. Verifica-se que, em geral, existe pouca informação sobre as rendas para casais na literatura atuarial. Numa primeira fase, demonstra-se a relevância e atualidade deste estudo, introduzem-se alguns conceitos e funções associadas ao comportamento da mortalidade humana, identificam-se os principais tipos de rendas sobre a vida humana individuais e para casais e derivam-se fórmulas para o cálculo dos seus valores atuariais. Por fim, realiza-se um estudo empírico dos valores atuariais de vários tipos de rendas vitalícias individuais e para casais, com base em tábuas de mortalidade portuguesas, para o cálculo de prémios de rendas vitalícias, propostas pela Swiss Re. Este estudo permite dar respostas a algumas questões relevantes relacionadas com as diferentes rendas vitalícias consideradas.; The duration of human life is constantly increasing. The systematic increase in longevity is a risk faced by Social Security...

Estimating life expectancy in small population areas

Bravo, Jorge; Malta, Joana
Fonte: EUROSTAT - European Commission Publicador: EUROSTAT - European Commission
Tipo: Parte de Livro
ENG
Relevância na Pesquisa
45.85%
In recent years we have seen an increasing demand for indicators of mortality for smaller (sub-national, sub-regional) areas, either to examine geographic inequalities in mortality, to monitor the effects of Public Health policies, to inform local strategies or to prepare long-term sub-national population projections. The usual way to obtain life expectancy indicators involves the construction of complete or abridged life tables. Attempts to calculate mortality rates directly from small numbers of counts and deaths often results in highly erratic schedules that are very difficult to interpret. In this paper we give an in-depth overview of the method adopted by Statistics Portugal for estimating life expectancy in small population (sub-national) areas (NUTS II and NUTS III). The method uses parametric graduation techniques to smooth crude age-specific mortality rates in order to construct a survival model presented in the form of a life table. We give an overview of parametric and nonparametric graduation methods and revisit the graduation methodology developed by the Continuous Mortality Investigation Bureau (CMIB) and its extension to generalized linear models, recently adopted by Statistics Portugal. The method uses a family of parametric (generalised Gompertz-Makeham) functions estimated by means of generalized linear models in order to graduate crude mortality estimates. We discuss the statistical tests and procedures used to evaluate the goodness-of-fit of the models. The methodology is empirically tested using data for the Portuguese sub-national region of Lisbon and for the period 2006-2008. We conclude that the Gompertz-Makeham functions estimated by means of generalized linear models offer a good alternative for estimating life expectancy in small population areas. The method is flexible and applicable to mortality data for a wide range of ages from any geographical conditions.

Life table of Hypothenemus hampei (Ferrari) in relation to coffee berry phenology under Colombian field conditions

Ruiz-Cárdenas,Ramiro; Baker,Peter
Fonte: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz" Publicador: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz"
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2010 EN
Relevância na Pesquisa
35.72%
The overlap of generations of coffee berry borer (CBB), Hypothenemus hampei (Ferrari) under field conditions in countries like Colombia hinders the construction of life tables by the sampling of natural populations. In this paper, a field methodology to carry out regular measurements of CBB cohorts inside coffee berries of different ages until harvest, both in coffee trees and in infested berries placed on the ground, is developed and used to compare the life history parameters of CBB. Populations with berries at six ages in three experimental stations (without CBB control) and in a commercial farm in Colombia (with chemical CBB control regularly carried out) were used. The duration of the pre-oviposition period as well as the mortality and survival rates of founder females and the proportion of founders leaving infested berries were strongly influenced by the consistency of berries, with optimum conditions for CBB reproduction as from 120-150 days after flowering. No differences were found between stations for the number of CBB developmental stages; but they had larger values than the commercial farm. The latter also had more than twice the average rate of founders leaving infested berries recorded in the stations. Survival functions (cumulative probabilities of survival) for the pest differed among treatments and between the plant and ground micro-environments. Age of berries at infestation was positively related to the intrinsic rate of increase of borer population; whilst generation time and doubling time were inversely related. No differences were found between sites for the main demographic parameters of the pest.

Covariate-dependent age-at-onset distributions for Huntington disease.

Krawczak, M; Bockel, B; Sandkuijl, L; Thies, U; Fenton, I; Harper, P S
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1991 EN
Relevância na Pesquisa
25.68%
A combined logistic regression and life-table analysis is presented on age-at-onset data for Huntington disease. Covariates included in the analysis were sex of the at-risk individual, parental age at onset, and sex of transmitting parent. Parental age at onset and parental sex were found to be significant covariates for age at onset in the offspring, and the appropriate logistic regression functions are calculated by maximum likelihood methods. These regression functions permit a more precise evaluation of carrier risks and likelihoods than hitherto was possible by simple computational means. We further introduce a novel method to account for sibship correlations in the significance assessment, using log-likelihood differences between different models.

Estimation of multi-state life table functions and their variability from complex survey data using the SPACE Program1

Cai, Liming; Hayward, Mark D.; Saito, Yasuhiko; Lubitz, James; Hagedorn, Aaron; Crimmins, Eileen
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 26/01/2010 EN
Relevância na Pesquisa
55.94%
The multistate life table (MSLT) model is an important demographic method to document life cycle processes. In this paper, we present the SPACE (Stochastic Population Analysis for Complex Events) program to estimate MSLT functions and their sampling variability. It has several advantages over other programs, including the use of micro-simulation and the bootstrap method to estimate the variance of MSLT functions. Simulation enables researchers to analyze a broader array of statistics than the deterministic approach, and may be especially advantageous in investigating distributions of MSLT functions. The bootstrap method takes sample design into account to correct the potential bias in variance estimates.

Lifespan extension of rotifers by treatment with red algal extracts

Snare, David J.; Fields, Allison M.; Snell, Terry W.; Kubanek, Julia
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
25.76%
Aging results from an accumulation of damage to macromolecules inhibiting cellular replication, repair, and other necessary functions. Damage may be due to environmental stressors such as metal toxicity, oxidative stress caused by imperfections in electron transfer reactions, or other metabolic processes. In an effort to discover medical treatments that counteract this damage, we initiated a search for small molecule drugs from natural sources using life table experiments which, through their unbiased approach, present the opportunity to discover first-in-class molecules. We have identified marine red algae as a source of natural products that slow aging of the invertebrate rotifer Brachionus manjavacas. Rotifers are a promising model organism for life extension studies as they maintain a short, measurable lifespan while also having an extensive literature related to aging. Rotifer lifespan was increased 9–14% by exposure to three of a total of 200 screened red algal extracts. Bioassay guided fractionation led to semi-purified extracts composed primarily of lipids responsible for rotifer life extension. The life extending mixture from the red alga Acanthophora spicifera contained eicosanoic, octadecanoic, and hexadecanoic acids as well as several unidentified unsaturated fatty acids. The life extending effects of these small molecule mixtures are not a result of their direct antioxidant capacity; other unknown mechanisms of action are likely involved. An understanding of how these natural products interact with their molecular targets could lead to selective and effective treatments for slowing aging and reducing age related diseases.

Utilisation de splines monotones afin de condenser des tables de mortalité dans un contexte bayésien

Patenaude, Valérie
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
FR
Relevância na Pesquisa
36.08%
Dans ce mémoire, nous cherchons à modéliser des tables à deux entrées monotones en lignes et/ou en colonnes, pour une éventuelle application sur les tables de mortalité. Nous adoptons une approche bayésienne non paramétrique et représentons la forme fonctionnelle des données par splines bidimensionnelles. L’objectif consiste à condenser une table de mortalité, c’est-à-dire de réduire l’espace d’entreposage de la table en minimisant la perte d’information. De même, nous désirons étudier le temps nécessaire pour reconstituer la table. L’approximation doit conserver les mêmes propriétés que la table de référence, en particulier la monotonie des données. Nous travaillons avec une base de fonctions splines monotones afin d’imposer plus facilement la monotonie au modèle. En effet, la structure flexible des splines et leurs dérivées faciles à manipuler favorisent l’imposition de contraintes sur le modèle désiré. Après un rappel sur la modélisation unidimensionnelle de fonctions monotones, nous généralisons l’approche au cas bidimensionnel. Nous décrivons l’intégration des contraintes de monotonie dans le modèle a priori sous l’approche hiérarchique bayésienne. Ensuite, nous indiquons comment obtenir un estimateur a posteriori à l’aide des méthodes de Monte Carlo par chaînes de Markov. Finalement...

Comparison of Belowground Biomass in C3- and C4-Dominated Mixed Communities in a Chesapeake Bay Brackish Marsh

Saunders, Colin J.; Megonigam, J. Patrick; Reynolds, James F.
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
25.72%
Belowground biomass is a critical factor regulating ecosystem functions of coastal marshes, including soil organic matter (SOM) accumulation and the ability of these systems to keep pace with sea-level rise. Nevertheless, belowground biomass responses to environmental and vegetation changes have been given little emphasis marsh studies. Here we present a method using stable carbon isotopes and color to identify root and rhizomes of Schoenoplectus americanus (Pers.) Volk. ex Schinz and R. Keller (C3) and Spartina patens (Ait.) Muhl. (C4) occurring in C3− and C4-dominated communities in a Chesapeake Bay brackish marsh. The functional significance of the biomass classes we identified is underscored by differences in their chemistry, depth profiles, and variation in biomass and profiles relative to abiotic and biotic factors. C3 rhizomes had the lowest concentrations of cellulose (29.19%) and lignin (14.43%) and the lowest C:N (46.97) and lignin:N (0.16) ratios. We distinguished two types of C3 roots, and of these, the dark red C3 roots had anomalously high C:N (195.35) and lignin:N (1.14) ratios, compared with other root and rhizome classes examined here and with previously published values. The C4-dominated community had significantly greater belowground biomass (4119.1 g m−2) than the C3-dominated community (3256.9 g m−2)...

Using reinforcement learning to control advanced life support systems

Klein, Theresa J.
Fonte: Universidade Rice Publicador: Universidade Rice
ENG
Relevância na Pesquisa
25.69%
This thesis deals with the application of reinforcement learning techniques to the control of a closed life support system simulator, such as could be used on a long duration space mission. We apply reinforcement learning to two different aspects of the simulator, control of recycling subsystems, and control of crop planting schedules. Comparisons are made between distributed and centralized controllers, generalized and non-generalized RL, and between different approaches to the construction of the state table and the design of reward functions. Distributed controllers prove to be superior to centralized controllers both in terms of speed and performance of the controller. Generalization helps to speed convergence, but the performance of the policy derived is dependent on the shape of the reward function.

Demographic window to aging in the wild: constructing life tables and estimating survival functions from marked individuals of unknown age

Müller, Hans-Georg; Wang, Jane-Ling; Carey, James R.; Caswell-Chen, Edward P.; Chen, Carl; Papadopoulos, Nikos; Yao, Fang
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /06/2004 EN
Relevância na Pesquisa
35.75%
We address the problem of establishing a survival schedule for wild populations. A demographic key identity is established, leading to a method whereby age-specific survival and mortality can be deduced from a marked cohort life table established for individuals that are randomly sampled at unknown age and marked, with subsequent recording of time-to-death. This identity permits the construction of life tables from data where the birth date of subjects is unknown. An analogous key identity is established for the continuous case in which the survival schedule of the wild population is related to the density of the survival distribution in the marked cohort. These identities are explored for both life tables and continuous lifetime data. For the continuous case, they are implemented with statistical methods using non-parametric density estimation methods to obtain flexible estimates for the unknown survival distribution of the wild population. The analytical model provided here serves as a starting point to develop more complex models for residual demography, i.e. models for estimating survival of wild populations in which age-at-entry is unknown and using remaining information in randomly encountered individuals. This is a first step towards a broad new concept of 'expressed demographic information content of marked or captured individuals'.

Estimação de curvas de sobrevivência para estudos de custo-efetividade

Herrmann, Letícia
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Trabalho de Conclusão de Curso Formato: application/pdf
POR
Relevância na Pesquisa
25.62%
Esta monografia tem como objetivo principal produzir um material prático e claro sobre análise de dados de sobrevivência, que possa vir a auxiliar aos que desejarem utilizar essas técnicas, especialmente quando aplicadas a estudos de custo-efetividade. Entende-se por dados de sobrevivência dados provenientes de estudos longitudinais em que indivíduos são acompanhados até a ocorrência do evento de interesse. A análise de sobrevivência modela o tempo até a ocorrência do evento de interesse e incorpora a informação das censuras, ou seja, utiliza o tempo até a censura daqueles indivíduos que participaram do estudo e não falharam. Neste trabalho, são introduzidos os principais conceitos e funções da análise de sobrevivência, como também são apresentadas diferentes maneiras de executá-la. Além da descrição dos modelos mais conhecidos da análise de sobrevivência, como os modelos não-paramétricos de Kaplan-Meier e a tábua de vida, são apresentados também os modelos paramétricos e modelos de regressão paramétricos, que são amplamente utilizados em análise de custo-efetividade por permitirem a extrapolação da função de sobrevivência. Para estas técnicas, foi desenvolvido um exemplo passo a passo no software STATA...

Properties of a Stochastic Model for Life Table Data: Exploring Life Expectancy Limits

Skiadas, Christos H; Skiadas, Charilaos
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 10/01/2011
Relevância na Pesquisa
45.86%
In this paper we explore the life expectancy limits by based on the stochastic modeling of mortality and applying the first exit or hitting time theory of a stochastic process. The main assumption is that the health state or the "vitality", according to Strehler and Mildvan, of an individual is a stochastic variable and thus it was introduced and applied a first exit time density function to mortality data. The model is used to estimate the development of mortality rates in the late stages of the human life span, to make better fitting to population mortality data including the infant mortality, to compare it with the classical Gompertz curve, and to make comparisons between the Carey med-fly data and the population mortality data estimating the health state or "vitality" functions. Furthermore, we apply the model to the life table data of Italy, France, USA, Canada, Sweden, Norway and Japan, and we analyze the characteristic parameters of the model and make forecasts.; Comment: 9 pages, 2 figures

Implementing generating functions to obtain power indices with coalition configuration

Veiga, Jorge Rodríguez; Flores, Guido I. Novoa; Méndez, Balbina V. Casas
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 01/07/2015
Relevância na Pesquisa
25.68%
We consider the Banzhaf-Coleman and Owen power indices for weighted majority games modified by a coalition configuration. We present calculation algorithms of them that make use of the method of generating functions. We programmed the procedure in the open language R and it is illustrated by a real life example taken from social sciences.; Comment: 14 pages, 1 Table

On some claims in Ramanujan's `unpublished' manuscript on the partition and tau functions

Moree, Pieter
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
25.68%
Towards the end of his life Ramanujan wrote a manuscript on properties of the partition and tau functions, some parts of which remained unpublished until very recently. Nevertheless, this manuscript gave rise to a lot of subsequent work. In it Ramanujan considers congruences for $\tau(n)$ modulo some special primes q. He proves for example that $\tau(n)\equiv \sum_{d|n}d^{11}({\rm mod}691)$. He defines $t_n=1$ if $\tau(n)$ is not divisible by q and $t_n=0$ otherwise. He then typically writes: "It can be shown by transcendental methods that $$ \sum_{k=1}^n t_k=C\int_1^n {dx\over (\log x)^{\delta}}+O({n\over (\log n)^r}). $$ where r is any positive number" (after stating some weaker estimates for the above sum). The number $\delta$ is a positve rational number depending on q and for the positive number C Ramanujan usually wrote down an Euler product. In this paper it is shown that Ramanujan's claim for every $r>1+\delta$ and each of the special primes q is false. Furthermore, we correct a 1928 paper of Geraldine Stanley who claimed to have disproved Ramanujan's claim in case q=5.; Comment: 14 pages, 1 table. Slightly revised version that will appear in The Ramanujan Journal

Consistency Techniques for Flow-Based Projection-Safe Global Cost Functions in Weighted Constraint Satisfaction

Lee, J. H. M.; Leung, Ka Lun
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 18/01/2014
Relevância na Pesquisa
25.79%
Many combinatorial problems deal with preferences and violations, the goal of which is to find solutions with the minimum cost. Weighted constraint satisfaction is a framework for modeling such problems, which consists of a set of cost functions to measure the degree of violation or preferences of different combinations of variable assignments. Typical solution methods for weighted constraint satisfaction problems (WCSPs) are based on branch-and-bound search, which are made practical through the use of powerful consistency techniques such as AC*, FDAC*, EDAC* to deduce hidden cost information and value pruning during search. These techniques, however, are designed to be efficient only on binary and ternary cost functions which are represented in table form. In tackling many real-life problems, high arity (or global) cost functions are required. We investigate efficient representation scheme and algorithms to bring the benefits of the consistency techniques to also high arity cost functions, which are often derived from hard global constraints from classical constraint satisfaction. The literature suggests some global cost functions can be represented as flow networks, and the minimum cost flow algorithm can be used to compute the minimum costs of such networks in polynomial time. We show that naive adoption of this flow-based algorithmic method for global cost functions can result in a stronger form of null-inverse consistency. We further show how the method can be modified to handle cost projections and extensions to maintain generalized versions of AC* and FDAC* for cost functions with more than two variables. Similar generalization for the stronger EDAC* is less straightforward. We reveal the oscillation problem when enforcing EDAC* on cost functions sharing more than one variable. To avoid oscillation...

Universal Scaling in the Branching of the Tree of Life

Herrada, E. Alejandro; Tessone, Claudio J.; Klemm, Konstantin; Eguíluz, Víctor M.; Hernández-García, Emilio; Duarte, Carlos M.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artículo Formato: 275474 bytes; 64512 bytes; 29184 bytes; 1217698 bytes; 2657462 bytes; 2581150 bytes; application/pdf; application/msword; application/msword; image/tiff; image/tiff; image/tiff
ENG
Relevância na Pesquisa
25.76%
6 pages.-- Supplementary material attached: Text S1. Scaling of branch size and cumulative branch size: TreeBASE vs. manually selected data sets.- Table S1. Break-down of the number of analyzed inter- and intra-species trees with respect to taxa.- Fig. S1. Cumulative complementary distribution functions (CCDFs) for branch size (F(A), panel A) and cumulative branch size (F(C), panel B).- Fig. S2. A: An example of an intraspecific phylogenetic tree, B: The allometric scaling plot showing the relationship of cumulative branch size (C) to branch size (A) from each node of that tree.- Fig. S3: Another example of an interspecific phylogenetic tree.; Understanding the patterns and processes of diversification of life in the planet is a key challenge of science. The Tree of Life represents such diversification processes through the evolutionary relationships among the different taxa, and can be extended down to intra-specific relationships. Here we examine the topological properties of a large set of interspecific and intraspecific phylogenies and show that the branching patterns follow allometric rules conserved across the different levels in the Tree of Life, all significantly departing from those expected from the standard null models. The finding of non-random universal patterns of phylogenetic differentiation suggests that similar evolutionary forces drive diversification across the broad range of scales...

A comparison of parametric models for mortality graduation. Application to mortality data of the Valencia Region (Spain)

Ana M. Debón, Francisco Montes, Ramon Sala
Fonte: Universidade Autônoma de Barcelona Publicador: Universidade Autônoma de Barcelona
Tipo: Artigo de Revista Científica Formato: application/pdf
Publicado em //2005 ENG
Relevância na Pesquisa
35.68%
The parametric graduation of mortality data has as its objective the satisfactory estimation of the death rates based on mortality data but using an age-dependent function whose parameters are adjusted from the crude rates obtainable directly from the data. This paper proposes a revision of the most commonly used parametric methods and compares the results obtained with each of them when they are applied to the mortality data for the Valencia Region. As a result of the comparison, we conclude that the Gompertz-Makeham functions estimated by means of generalized linear models lead to the best results. Our working method is of additional interest for being applicable to mortality data for a wide range of ages from any geographical conditions, allowing us to select the most appropriate life table for the case in hand.; La gradualització paramètrica de dades de mortalitat té com a objectiu l’estimació correcta de taxes de mort a partir de les dades de mortalitat mitjançant una funció que depèn de l’edat, els paràmetres de la qual s’ajusten a partir de les taxes ”brutes” de mortalitat obtingudes directament de les dades. Aquest article presenta una revisió dels models paramètrics més habituals i la seua aplicació a les dades de mortalitat del País Valencià. Com a conseqüència de la comparació dels resultats obtinguts amb els diferents models...

Application of stochastic models on the portuguese population and distortion to workers conpensation pensioners experience

Nkwenti, Mbelli Njah
Fonte: Instituto Superior de Economia e Gestão Publicador: Instituto Superior de Economia e Gestão
Tipo: Dissertação de Mestrado
Publicado em //2015 ENG
Relevância na Pesquisa
65.94%
Mestrado em Ciências Actuariais; Este estudo resulta de um estágio na AXA, e visa contribuir para a correta determinação das reservas que cobrem os encargos futuros com as indemnizações no Ramo de Acidentes de Trabalho (AT). A questão é muito relevante para as pensões ditas "não obrigatoriamente remíveis", pois a autoridade supervisora (ASF) deixa em parte ao critério das companhias qual o modelo de mortalidade a aplicar. O objetivo do estágio foi assim o desenvolvimento de um modelo estocástico para a mortalidade dos pensionistas em análise, para o que foi necessário considerar inicialmente toda a população portuguesa, passando-se depois para a população constituída pelos trabalhadores cobertos por apólices de AT e, finalmente, para os segurados na AXA. O modelo global é composto por um modelo estocástico para a mortalidade da população e um modelo de mortalidade para o portfólio, obtido a partir de três modelos relacionais (Cox Proportional, Brass Linear and Workgroup PLT). As probabilidades de morte a um ano para as idades 0-110 (período 2013-2113), foram calculadas para a população em geral e para as duas carteiras e utilizadas na construção das correspondentes tábuas de mortalidade e funções associadas. Pôde então determinar-se o montante das reservas relativas aos pensionistas...

Tabela de vida de Hypothenemus hampei (Ferrari) em relação à fenologia do fruto de café, sob condições de campo, na Colômbia; Life table of Hypothenemus hampei (Ferrari) in relation to coffee berry phenology under Colombian field conditions

Ruiz-Cárdenas, Ramiro; Baker, Peter
Fonte: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz Publicador: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; Formato: application/pdf
Publicado em 01/12/2010 ENG
Relevância na Pesquisa
35.72%
The overlap of generations of coffee berry borer (CBB), Hypothenemus hampei (Ferrari) under field conditions in countries like Colombia hinders the construction of life tables by the sampling of natural populations. In this paper, a field methodology to carry out regular measurements of CBB cohorts inside coffee berries of different ages until harvest, both in coffee trees and in infested berries placed on the ground, is developed and used to compare the life history parameters of CBB. Populations with berries at six ages in three experimental stations (without CBB control) and in a commercial farm in Colombia (with chemical CBB control regularly carried out) were used. The duration of the pre-oviposition period as well as the mortality and survival rates of founder females and the proportion of founders leaving infested berries were strongly influenced by the consistency of berries, with optimum conditions for CBB reproduction as from 120-150 days after flowering. No differences were found between stations for the number of CBB developmental stages; but they had larger values than the commercial farm. The latter also had more than twice the average rate of founders leaving infested berries recorded in the stations. Survival functions (cumulative probabilities of survival) for the pest differed among treatments and between the plant and ground micro-environments. Age of berries at infestation was positively related to the intrinsic rate of increase of borer population; whilst generation time and doubling time were inversely related. No differences were found between sites for the main demographic parameters of the pest.; A superposição de gerações da broca do café...