Three-dimensional model for multi-component reactive transport with variable density groundwater flow

PHWAT is a new model that couples a geochemical reaction model (PHREEQC-2) with a density-dependent groundwater flow and solute transport model (SEAWAT) using the split-operator approach. PHWAT was developed to simulate multi-component reactive transport in variable density groundwater flow. Fluid density in PHWAT depends not on only the concentration of a single species as in SEAWAT, but also the concentrations of other dissolved chemicals that can be subject to reactive processes. Simulation results of PHWAT and PHREEQC-2 were compared in their predictions of effluent concentration from a column experiment. Both models produced identical results, showing that PHWAT has correctly coupled the sub-packages. PHWAT was then applied to the simulation of a tank experiment in which seawater intrusion was accompanied by cation exchange. The density dependence of the intrusion and the snow-plough effect in the breakthrough curves were reflected in the model simulations, which were in good agreement with the measured breakthrough data. Comparison simulations that, in turn, excluded density effects and reactions allowed us to quantify the marked effect of ignoring these processes. Next, we explored numerical issues involved in the practical application of PHWAT using the example of a dense plume flowing into a tank containing fresh water. It was shown that PHWAT could model physically unstable flow and that numerical instabilities were suppressed. Physical instability developed in the model in accordance with the increase of the modified Rayleigh number for density-dependent flow, in agreement with previous research. (c) 2004 Elsevier Ltd. All rights reserved.

Allergic asthma in patients with common variable immunodeficiency

P>Background: Many patients with common variable immunodeficiency (CVID) have a clinical history suggestive of allergic respiratory disease. However, in such individuals, the prevalence of asthma and the role of atopy have not been well established. The objective of this study was to evaluate pulmonary function and identify asthma in patients with CVID. We also investigated the role of IgE as a trigger of asthma in these patients. Methods: Sixty-two patients diagnosed with CVID underwent spirometry, as well as skin prick testing and in vitro determination of serum-specific IgE levels for aeroallergens, together with bronchial provocation with histamine and allergen. Results: The most common alteration identified through spirometry was obstructive lung disease, which was observed in 29 (47.5%) of the 62 patients evaluated. Eighteen (29.0%) of the 62 patients had a clinical history suggestive of allergic asthma. By the end of the study, asthma had been diagnosed in nine (14.5%) patients and atopy had been identified in six (9.7%). In addition, allergic asthma had been diagnosed in four patients (6.5% of the sample as a whole; 22.2% of the 18 patients with a clinical history suggestive of the diagnosis). Conclusion: In this study, CVID patients testing negative for specific IgE antibodies and suspected of having allergic asthma presented a positive response to bronchial provocation tests with allergens. To our knowledge, this is the first such study. When CVID patients with a history suggestive of allergic asthma test negative on traditional tests, additional tests designed to identify allergic asthma might be conducted.

Impact of Atypical Retardation Patterns on Detection of Glaucoma Progression using the GDx with Variable Corneal Compensation

PURPOSE: To evaluate the impact of atypical retardation patterns (ARP) on detection of progressive retinal nerve fiber layer (RNFL) loss using scanning laser polarimetry with variable corneal compensation (VCC). DESIGN: Observational cohort study. METHODS: The study included 377 eyes of 221 patients with a median follow-up of 4.0 years. Images were obtained annually with the GDx VCC (Carl Zeiss Med, itec Inc, Dublin, California, USA), along with optic disc stereophotographs and standard automated perimetry (SAP) visual fields. Progression was determined by the Guided Progression Analysis software for SAP and by masked assessment of stereophotographs by expert graders. The typical scan score (TSS) was used to quantify the presence of ARPs on GDx VCC images. Random coefficients models were used to evaluate the relationship between ARP and RNFL thickness measurements over time. RESULTS: Thirty-eight eyes (10%) showed progression over time on visual fields, stereophotographs, or both. Changes in TSS scores from baseline were significantly associated with changes in RNFL thickness measurements in both progressing and nonprogressing eyes. Each I unit increase in TSS score was associated with a 0.19-mu m decrease in RNFL thickness measurement (P < .001) over time. CONCLUSIONS: ARPs had a significant effect on detection of progressive RNFL loss with the GDx VCC. Eyes with large amounts of atypical patterns, great fluctuations on these patterns over time, or both may show changes in measurements that can appear falsely as glaucomatous progression or can mask true changes in the RNFL. (Am J Ophthalmol 2009;148:155-163. (C) 2009 by Elsevier Inc. All rights reserved.)

A variable stepsize implementation for stochastic differential equations

Stochastic differential equations (SDEs) arise from physical systems where the parameters describing the system can only be estimated or are subject to noise. Much work has been done recently on developing higher order Runge-Kutta methods for solving SDEs numerically. Fixed stepsize implementations of numerical methods have limitations when, for example, the SDE being solved is stiff as this forces the stepsize to be very small. This paper presents a completely general variable stepsize implementation of an embedded Runge Kutta pair for solving SDEs numerically; in this implementation, there is no restriction on the value used for the stepsize, and it is demonstrated that the integration remains on the correct Brownian path.

Control of Aedes vectors of dengue in three provinces of Vietnam by use of Mesocyclops (Copepoda) and community-based methods validated by entomologic, clinical, and serological surveillance

We describe remarkable success in controlling dengue vectors, Aedes aegypti (L.) and Aedes albopictus (Skuse), in 6 communes with 11,675 households and 49,647 people in the northern provinces of Haiphong, Hung Yen, and Nam Dinh in Vietnam. The communes were selected for high-frequency use of large outdoor concrete tanks and wells. These were found to be the source of 49.6-98.4% of Ae. aegypti larvae, which were amenable to treatment with local Mesocyclops, mainly M. woutersi Van der Velde, M. aspericornis (Daday) and M. thermocyclopoides Harada. Knowledge, attitude, and practice surveys were performed to determine whether the communities viewed dengue and dengue hemorrhagic fever as a serious health threat; to determine their knowledge of the etiology, attitudes, and practices regarding control methods including Mesocyclops; and to determine their receptivity to various information methods. On the basis of the knowledge, attitude, and practice data, the community-based dengue control program comprised a system of local leaders, health volunteer teachers, and schoolchildren, supported by health professionals. Recycling of discards for economic gain was enhanced, where appropriate, and this, plus 37 clean-up campaigns, removed small containers unsuitable for Mesocyclops treatment. A previously successful eradication at Phan Boi village (Hung Yen province) was extended to 7 other villages forming Di Su commune (1,750 households) in the current study. Complete control was also achieved in Nghia Hiep (Hung Yen province) and in Xuan Phong (Nam Dinh province); control efficacy was greater than or equal to 99.7% in the other 3 communes (Lac Vien in Haiphong, Nghia Dong, and Xuan Kien in Nam Dinh). Although tanks and wells were the key container types of Ae. aegypti productivity, discarded materials were the source of 51% of the standing crop of Ae. albopictus. Aedes albopictus larvae were eliminated from the 3 Nam Dinh communes, and 86-98% control was achieved in the other 3 communes. Variable dengue attack rates made the clinical and serological comparison of control and untreated communes problematic, but these data indicate that clinical surveillance by itself is inadequate to monitor dengue transmission.

A comparison of two methods for the calculation of accumulated oxygen deficit

The aim of this study was to compare accumulated oxygen deficit data derived using two different exercise protocols with the aim of producing a less time-consuming test specifically for use with athletes. Six road and four track male endurance cyclists performed two series of cycle ergometer tests. The first series involved five 10 min sub-maximal cycle exercise bouts, a (V) over dotO(2peak) test and a 115% (V) over dotO(2peak) test. Data from these tests were used to estimate the accumulated oxygen deficit according to the calculations of Medbo et al. (1988). In the second series of tests, participants performed a 15 min incremental cycle ergometer test followed, 2 min later, by a 2 min variable resistance test in which they completed as much work as possible while pedalling at a constant rate. Analysis revealed that the accumulated oxygen deficit calculated from the first series of tests was higher (P< 0.02) than that calculated from the second series: 52.3 +/- 11.7 and 43.9 +/- 6.4 ml . kg(-1), respectively (mean +/- s). Other significant differences between the two protocols were observed for (V) over dot O-2peak, total work and maximal heart rate; all were higher during the modified protocol (P

Preparação para a performance instrumental: problemáticas e estratégias: relatório de estágio

Resumo I (Prática Pedagógica) - Nesta seção do relatório de estágio pretende-se caraterizar e apresentar todos os elementos referentes à prática pedagógica, que fizeram parte do estágio do ensino especializado da música, realizado na Escola de Música do Orfeão de Leiria no ano letivo de 2013/2014. De uma forma geral, o relatório de estágio pretende colocar em evidência aspetos pedagógicos como metodologias de ensino, questões motivacionais, estilos de aprendizagem, entre outros. Durante um ano letivo completo foram analisados, com especial atenção, três alunos que foram envolvidos no estágio, construindo e modelando os seus processos de aprendizagem. Para cada um deles foi realizado, ao longo do ano letivo, 30 planos de aula, uma planificação anual e três gravações vídeo/áudio em contexto de aula. Não foi uma tarefa nada fácil de realizar, mas que trouxe inúmeros conhecimentos não só de caráter pedagógico mas também de caráter pessoal. A parte inicial desta seção será dedicada à descrição e caraterização da escola onde foi realizado o estágio, a Escola de Música do Orfeão de Leiria/Conservatório de Artes. Será feita uma pequena abordagem histórica da instituição, bem como do seu projeto educativo, dacomunidade escolar, do seu contexto sociocultural e da classe de saxofone. Será apresentada também uma caraterização dos alunos, segundo vários parâmetros. Posteriormente, serão descritas algumas das práticas educativas desenvolvidas, com os alunos, em contexto de estágio. Para tal, serão utilizados como instrumentos, não só a experiência ativa do docente/estagiário, mas também todas as gravações, planos de aulas e planificações anuais, realizados em contexto de estágio do ensino especializado. Por fim, será realizada uma reflexão crítica do desempenho como docente de saxofone no âmbito do estágio e uma conclusão de toda a seção da prática pedagógica.

Disability in instrumental activities of daily living among older adults: gender differences

OBJECTIVE To analyze gender differences in the incidence and determinants of disability regarding instrumental activities of daily living among older adults. METHODS The data were extracted from the Saúde, Bem-Estar e Envelhecimento (SABE – Health, Wellbeing and Ageing) study. In 2000, 1,034 older adults without difficulty in regarding instrumental activities of daily living were selected. The following characteristics were evaluated at the baseline: sociodemographic and behavioral variables, health status, falls, fractures, hospitalizations, depressive symptoms, cognition, strength, mobility, balance and perception of vision and hearing. Instrumental activities of daily living such as shopping and managing own money and medication, using transportation and using the telephone were reassessed in 2006, with incident cases of disability considered as the outcome. RESULTS The incidence density of disability in instrumental activities of daily living was 44.7/1,000 person/years for women and 25.2/1,000 person/years for men. The incidence rate ratio between women and men was 1.77 (95%CI 1.75;1.80). After controlling for socioeconomic status and clinical conditions, the incidence rate ratio was 1.81 (95%CI 1.77;1.84), demonstrating that women with chronic disease and greater social vulnerability have a greater incidence density of disability in instrumental activities of daily living. The following were determinants of the incidence of disability: age ≥ 80 and worse perception of hearing in both genders; stroke in men; and being aged 70 to 79 in women. Better cognitive performance was a protective factor in both genders and better balance was a protective factor in women. CONCLUSIONS The higher incidence density of disability in older women remained even after controlling for adverse social and clinical conditions. In addition to age, poorer cognitive performance and conditions that adversely affect communication disable both genders. Acute events, such as a stroke, disables elderly men more, whereas early deficits regarding balance disable women more.

EVALUATION OF FOUR DIFFERENT DNA EXTRACTION METHODS IN COAGULASE-NEGATIVE STAPHYLOCOCCI CLINICAL ISOLATES

Currently there are several methods to extract bacterial DNA based on different principles. However, the amount and the quality of the DNA obtained by each one of those methods is highly variable and microorganism dependent, as illustrated by coagulase-negative staphylococci (CoNS) which have a thick cell wall that is difficult to lyse. This study was designed to compare the quality and the amount of CoNS DNA, extracted by four different techniques: two in-house protocols and two commercial kits. DNA amount and quality determination was performed through spectrophotometry. The extracted DNA was also analyzed using agarose gel electrophoresis and by PCR. 267 isolates of CoNS were used in this study. The column method and thermal lyses showed better results with regard to DNA quality (mean ratio of A260/280 = 1.95) and average concentration of DNA (), respectively. All four methods tested provided appropriate DNA for PCR amplification, but with different yields. DNA quality is important since it allows the application of a large number of molecular biology techniques, and also it's storage for a longer period of time. In this sense the extraction method based on an extraction column presented the best results for CoNS.

Sobrecarga e qualidade de vida em cuidadores informais de pessoas com demência

RESUMO: Introdução: A sobrecarga do cuidador informal de pessoas com demência está associada à sua qualidade de vida. Objetivo: Analisar as associações entre qualidade de vida e sobrecarga familiar nestes cuidadores informais, assim como as relações entre estas variáveis e outros fatores. Materiais e métodos: Trata-se de um estudo transversal (descritivo e analítico). A amostra de conveniência foi composta de 33 cuidadores. O estudo foi realizado nos serviços de consultas externas de dois centros do Instituto das Irmãs Hospitaleiras do Sagrado Coração de Jesus. Os dados foram obtidos através da aplicação das escalas: Entrevista de Sobrecarga de Zarit, WHOQOL-Bref, Escala de Atividades Instrumentais de Vida Diária de Lawton e Brody e Índice de Barthel. Na análise dos dados foram empregues estatísticas descritivas e testes não paramétricos. Os testes empregues consistiram no teste de Mann-Whitney e teste de Kruskal-Wallis. O nível de significância considerado em todas as análises foi de 5%. Todos os dados obtidos foram analisados com recurso ao programa estatístico SPSS 21.0. Resultados: Os cuidadores com menores índices de sobrecarga evidenciaram uma correlação negativa com todos os domínios da qualidade de vida (p≤0.002). Os cuidadores homens revelaram-se menos sobrecarregados enquanto cuidadores principais (p=0.023). A existência de um cuidador secundário foi indicador de uma melhor qualidade de vida dos cuidadores, nos domínios das relações sociais (p=0.034) e do meio ambiente (p=0.034). Quanto mais prolongado o tempo de cuidados para os cuidadores avaliados, menor a sua qualidade de vida, ao nível físico (p=0.003) e do meio ambiente (p=0.000). A situação de sobrecarga foi tanto maior quanto menor a idade do cuidador (p=0.003). A independência da pessoa com demência ao nível instrumental também se traduziu numa melhor qualidade de vida dos cuidadores, em todos os domínios desta variável e, numa menor situação de sobrecarga dos cuidadores (p=0.017). Conclusões: Uma maior sobrecarga dos cuidadores informais de pessoas com demência está associada a indicadores mais baixos de qualidade de vida, em todos domínios desta variável. No presente estudo, os principais fatores a ter em conta na avaliação dos cuidadores de pessoas com demência foram: o género, a existência de um cuidador secundário e a independência da pessoa cuidada nas atividades instrumentais da vida diária. Foi também possível analisar que as variáveis sobrecarga e qualidade de vida não se relacionam apenas entre si mas, concomitantemente, com diferentes situações da vida do cuidador. Uma intervenção mais atenta às características de cada cuidador poderia vir a repercutir-se numa menor sobrecarga e numa melhor qualidade de vida, quer do cuidador como, eventualmente, da pessoa cuidada.------------ ABSTRACT: Introduction and objectives: The overload of informal caregivers of people with dementia tends to be inversely associated with their life quality. This study aims to analyze the associations between the family overload and the life quality of these informal caregivers, as well as the relationships between these variables and other sociodemographic and functional factors. Population and methods: It’s a cross-sectional study (descriptive and analytical). The convenience sample was composed of 33 informal caregivers. The study was carried out in the external services consultations of two centers of the Institute of the Hospitable Sisters of the Sacred Heart of Jesus. The data were obtained by applying the following scales: Overload Interview of Zarit, WHOQOL-Bref, Scale of Instrumental Activities of Daily Living of Lawton and Brody, and Barthel Index. Results: We found a negative correlation between the family overload and every domains of life quality (p ≤ 0.002). The men caregivers proved to be less burdened than the main caregivers (p = 0.023). The existence of a secondary caregiver was an indicator of a better life quality in the fields of social relations (p = 0.034) and in the environment (p = 0.034). The evaluated caregivers, more prolonged time occupy to care, lower was their life quality on the physical level (p = 0.003) and on the environment (p = 0.000). The overload levels were bigger whereas the lower age of the caregiver (p = 0.003). The independence of the person with dementia on the instrumental level rendered a better life quality for caregivers in all domains of this variable and also provided a minor burden for the caregivers (p = 0.017). Conclusions: In this small sample, the higher burden to the informal caregivers of people with dementia is associated with lower indicators of life quality, in every domains of this variable. In this study, the main factors to keep in count in the evaluation to the caregivers of people with dementia were: the gender, the existence of a secondary caregiver and the independence of the person to be cared in his instrumental activities of daily living. We also observed that the overload and life quality variables do not relate only to each other but at the same time with different situations of the life of the caregiver. A closer intervention to the characteristics of each caregiver could reflect a lower overload and a better life quality of the caregiver and eventually as well as the person to be cared of.

Integration methods in dynamic analysis

"Series title: Springerbriefs in applied sciences and technology, ISSN 2191-530X"

Estimation of dynamic latent variable models using simulated nonparametric moments

Given a model that can be simulated, conditional moments at a trial parameter value can be calculated with high accuracy by applying kernel smoothing methods to a long simulation. With such conditional moments in hand, standard method of moments techniques can be used to estimate the parameter. Since conditional moments are calculated using kernel smoothing rather than simple averaging, it is not necessary that the model be simulable subject to the conditioning information that is used to define the moment conditions. For this reason, the proposed estimator is applicable to general dynamic latent variable models. Monte Carlo results show that the estimator performs well in comparison to other estimators that have been proposed for estimation of general DLV models.

Stochastic Search Variable Selection in Vector Error Correction Models with an Application to a Model of the UK Macroeconomy

This paper develops methods for Stochastic Search Variable Selection (currently popular with regression and Vector Autoregressive models) for Vector Error Correction models where there are many possible restrictions on the cointegration space. We show how this allows the researcher to begin with a single unrestricted model and either do model selection or model averaging in an automatic and computationally efficient manner. We apply our methods to a large UK macroeconomic model.

Variable viral clearance despite adequate ganciclovir plasma levels during valganciclovir treatment for cytomegalovirus disease in D+/R- transplant recipients.

ABSTRACT: BACKGROUND: Valganciclovir, the oral prodrug of ganciclovir, has been demonstrated equivalent to iv ganciclovir for CMV disease treatment in solid organ transplant recipients. Variability in ganciclovir exposure achieved with valganciclovir could be implicated as a contributing factor for explaining variations in the therapeutic response. This prospective observational study aimed to correlate clinical and cytomegalovirus (CMV) viral load response (DNAemia) with ganciclovir plasma concentrations in patients treated with valganciclovir for CMV infection/disease. METHODS: Seven CMV D+/R- transplant recipients (4 kidney, 2 liver and 1 heart) were treated with valganciclovir (initial dose was 900-1800 mg/day for 3-6.5 weeks, followed by 450-900 mg/day for 2-9 weeks). DNAemia was monitored by real time quantitative PCR and ganciclovir plasma concentration was measured at trough (Ctrough) and 3 h after drug administration (C3h) by HPLC. RESULTS: Four patients presented with CMV syndrome, two had CMV tissue-invasive disease after prophylaxis discontinuation, and one liver recipient was treated pre-emptively for asymptomatic rising CMV viral load 5 weeks post-transplantation in the absence of prophylaxis. CMV DNAemia decreased during the first week of treatment in all recipients except in one patient (median decrease: -1.2 log copies/mL, range: -1.8 to 0) despite satisfactory ganciclovir exposure (AUC0-12 = 48 mg.h/L, range for the 7 patients: 40-118 mg.h/L). Viral clearance was obtained in five patients after a median of time of 34 days (range: 28-82 days). Two patients had recurrent CMV disease despite adequate ganciclovir exposure (65 mg.h/L, range: 44-118 mg.h/L). CONCLUSIONS: Valganciclovir treatment for CMV infection/disease in D+/R- transplant recipients can thus result in variable viral clearance despite adequate ganciclovir plasma concentrations, probably correlating inversely with anti-CMV immune responses after primary infection.

Estimation of dynamic latent variable models using simulated nonparametric moments

Abstract. Given a model that can be simulated, conditional moments at a trial parameter value can be calculated with high accuracy by applying kernel smoothing methods to a long simulation. With such conditional moments in hand, standard method of moments techniques can be used to estimate the parameter. Because conditional moments are calculated using kernel smoothing rather than simple averaging, it is not necessary that the model be simulable subject to the conditioning information that is used to define the moment conditions. For this reason, the proposed estimator is applicable to general dynamic latent variable models. It is shown that as the number of simulations diverges, the estimator is consistent and a higher-order expansion reveals the stochastic difference between the infeasible GMM estimator based on the same moment conditions and the simulated version. In particular, we show how to adjust standard errors to account for the simulations. Monte Carlo results show how the estimator may be applied to a range of dynamic latent variable (DLV) models, and that it performs well in comparison to several other estimators that have been proposed for DLV models.