Graduação Byesiana e projeção de taxas de mortalidade aplicadas à populações de fundos de pensão do setor elétrico

Resumo: O processo de envelhecimento populacional que vem afetando a população mundial - o qual é caracterizado por quedas significativas nas taxas de mortalidade e fecundidade - tem afetado os sistemas de previdência e seguridade em todo o mundo, alertando-os a adotarem hipóteses biométricas cada vez mais conservadoras, impactando os cálculos atuariais. Essas tendências já começam a ser contempladas nos cálculos de provisões matemáticas e de benefícios através do uso de algumas ferramentas de construção de tábuas de mortalidade e projeções de taxas de mortalidade futuras. Diante disso, considerando a população de expostos ao risco de seis Entidades de Previdência Complementar Fechadas do sul do país – especificamente do setor elétrico – o objetivo deste estudo é graduar e projetar as taxas de mortalidade desta população, obtendo informações sobre seus níveis de mortalidade atuais e futuros, auxiliando na adoção da hipótese de mortalidade geral que melhor reflita a mortalidade do grupo. Para isto, aplicouse a técnica de Graduação Bayesiana de Taxas de Mortalidade utilizando simulação estocástica de Monte Carlo via Cadeias de Markov (MCMC) na população de assistidos das referidas Fundações, considerando os anos de estudo de 2000 a 2008, obtendo-se uma tábua de mortalidade para as idades entre 42 e 90 anos. Também foi utilizado o modelo demográfico de Lee-Carter para projeção das taxas de mortalidade raduadas, obtendo os respectivos fatores de melhoria a serem aplicados às mesmas, projetando-as para o futuro, tornando a tábua na forma geracional e obtendo o comportamento futuro dos níveis de mortalidade. A componente kt do modelo de Lee-Carter, que corresponde a uma série temporal que descreve a mudança na mortalidade ao longo do tempo, foi modelada por um processo ARIMA, o qual foi imulado estocasticamente utilizando bootstrap paramétrico, obtendo-se intervalos de confiança empíricos para as taxas de mortalidade observadas

Erratum to: Large-scale mitochondrial phylogeography in the halophilic fairy shrimp Phallocryptus spinosa (Milne-Edwards, 1840) (Branchiopoda: Anostraca)

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Proton Irradiation of CVD Diamond Detectors for High Luminosity Experiments at the LHC

CVD diamond shows promising properties for use as a position sensitive detector for experiments in the highest radiation areas at the Large Hadron Collider. In order to study the radiation hardn ess of diamond we exposed CVD diamond detector samples to 24~GeV/$c$ and 500~MeV protons up to a fluence of $5\times 10^{15}~p/{\rm cm^2}$. We measured the charge collection distance, the ave rage distance electron hole pairs move apart in an external electric field, and leakage currents before, during, and after irradiation. The charge collection distance remains unchanged up to $1\ times 10^{15}~p/{\rm cm^2}$ and decreases by $\approx$40~\% at $5\times 10^{15}~p/{\rm cm^2}$. Leakage currents of diamond samples were below 1~pA before and after irradiation. The particle indu ced currents during irradiation correlate well with the proton flux. In contrast to diamond, a silicon diode, which was irradiated for comparison, shows the known large increase in leakage curren t. We conclude that CVD diamond detectors are radiation hard to 24~GeV/$c$ and 500~MeV protons up to at least $1\times 10^{15}~p/{\rm cm^2}$ without signal loss

Micro-strip sensors based on CVD Diamond

In this article we present the performance of recent chemical vapour deposition (CVD) diamond micro-strip sensors in beam tests. In addition we present the first comparison of a CVD diamond micro-strip sensor before and after proton irradiation

Performance of irradiated CVD diamond micro-strip sensors

CVD diamond detectors are of interest for charged particle detection and tracking due to their high radiation tolerance. In this article we present, for the first time, beam test results from recently manufactured CVD diamond strip detectors and their behavior under low doses of electrons from a $\beta$-source and the performance before and after intense ($>10^{15}/{\rm cm^2}$) proton- and pion-irradiations. We find that low dose irradiations increase the signal-to-noise ratio (pumping of the signal) and slightly deteriorate the spatial resolution. Intense irradiations with protons ($2.2\times 10^{15}~p/{\rm cm^2}$) lowers the signal-to-noise ratio slightly. Intense irradiation with pions ($2.9\times 10^{15}~\pi/{\rm cm^2}$) lowers the signal-to-noise ratio more. The spatial resolution of the diamond sensors improves after irradiations

Transferrin-Liposome-Mediated Systemic p53 Gene Therapy in Combination with Radiation Results in Regression of Human Head and Neck Cancer Xenografts

This is the published version, also available here: http://dx.doi.org/10.1089/10430349950016357.The use of cationic liposomes as nonviral vehicles for the delivery of therapeutic molecules is becoming increasingly prevalent in the field of gene therapy. We have previously demonstrated that the use of the transferrin ligand (Tf) to target a cationic liposome delivery system resulted in a significant increase in the transfection efficiency of the complex [Xu, L., Pirollo, K.F., and Chang, E.H. (1997). Hum. Gene Ther. 8, 467-475]. Delivery of wild-type (wt) p53 to a radiation-resistant squamous cell carcinoma of the head and neck (SCCHN) cell line via this ligand-targeted, liposome complex was also able to revert the radiation resistant phenotype of these cells in vitro. Here we optimized the Tf/liposome/DNA ratio of the complex (LipT) for maximum tumor cell targeting, even in the presence of serum. The efficient reestablishment of wtp53 function in these SCCHN tumor cells in vitro, via the LipT complex, restored the apoptotic pathway, resulting in a significant increase in radiation-induced apoptosis that was directly proportional to the level of exogenous wtp53 in the tumor cells. More significantly, intravenous administration of LipT-p53 markedly sensitized established SCCHN nude mouse xenograft tumors to radiotherapy. The combination of systemic LipT-p53 gene therapy and radiation resulted in complete tumor regression and inhibition of their recurrence even 6 months after the end of all treatment. These results indicate that this tumor-specific, ligand-liposome delivery system for p53 gene therapy, when used in concert with conventional radiotherapy, can provide a new and more effective means of cancer treatment

Food Selectivity in Children with Autism: Guidelines for Assessment and Clinical Interventions

Autisms Spectrum Disorders (ASD) are characterized by core symptoms (social communication and restricted and repetitive behaviors) and related comorbidities, including sensory anomalies, feeding issues, and challenging behaviors. Children with ASD experience significantly more feeding problems than their peers. In fact, parents and clinicians have to manage daily the burden of various dysfunctional behaviors of children at mealtimes (food refusal, limited variety of food, single food intake, or liquid diet). These dysfunctional behaviors at mealtime depend on different factors that are either medical/sensorial or behavioral. Consequently, a correct assessment is necessary in order to program an effective clinical intervention. The aim of this study is to provide clinicians with a guideline regarding food selectivity concerning possible explanations of the phenomenon, along with a direct/indirect assessment gathering detailed and useful information about target feeding behaviors. Finally, a description of evidence-based sensorial and behavioral strategies useful also for parent-mediated intervention is reported addressing food selectivity in children with ASD