Associação entre medidas antropométricas e fatores de risco cardiovascular em crianças e adolescentes

FUNDAMENTO: A obesidade tem sido identificada como importante fator de risco no desenvolvimento de doenças cardiovasculares, porém outros fatores exercem influência, combinados ou não à obesidade, e devem ser considerados na estratificação de risco cardiovascular em pediatria. OBJETIVO: Analisar a associação entre medidas antropométricas e fatores de risco cardiovascular, investigar os determinantes para as mudanças da pressão arterial (PA) e propor uma equação de predição para circunferência de cintura (CC) em crianças e adolescentes. MÉTODOS: Foram avaliadas 1.950 crianças e adolescentes, com idade entre 7-18 anos. Foi investigada a gordura visceral pela CC e a relação cintura-quadril, PA e índice de massa corporal (IMC). Em uma subamostra selecionada aleatoriamente desses voluntários (n = 578), foram medidos o colesterol total, a glicemia e os triglicerídeos. RESULTADOS: A CC se correlacionou positivamente com o IMC (r = 0,85; p < 0,001) e a PA (PAS r = 0,45 e PAD = 0,37; p < 0,001). A glicemia e os triglicerídeos apresentaram correlação fraca com a CC (r = 0,110; p = 0,008 e r = 0,201; p < 0,001, respectivamente). O colesterol total não se correlacionou com nenhuma variável. Idade, IMC e CC foram preditores significativos nos modelos de regressão para PA (p < 0,001). Propõe-se uma equação de predição da CC para crianças e adolescentes: meninos: y = 17,243 + 0,316 (altura em cm); meninas: y = 25,197 + 0,256 (altura em cm). CONCLUSÃO: A CC está associada com fatores de risco cardiovascular e apresenta-se como fator preditor de risco para hipertensão em crianças e adolescentes. A equação de predição para CC proposta em nosso estudo deve ser testada em futuros trabalhos.

Excesso de Peso, Variáveis Antropométricas e Pressão Arterial em Escolares de 10 a 18 Anos

Fundamento: Estima-se que a prevalência de hipertensão em crianças e adolescentes varie entre 1-13%. O excesso de peso e a obesidade central estão relacionados aos níveis pressóricos em adultos e podem ser importantes na patogênese precoce da HAS quando presentes na infância. Objetivos: Identificar a associação entre variáveis antropométricas e níveis pressóricos em escolares de 5.ª a 8.ª séries e avaliar qual medida obteve maior correlação com a medida dos níveis pressóricos. Métodos: Estudo transversal contemporâneo com amostra de base populacional probabilística por conglomerados em escolas públicas do ensino fundamental de Porto Alegre, de alunos matriculados entre a 5.ª e a 8.ª série. Foram coletados dados sobre fatores de risco familiares e antropometria. A análise estatística incluiu correlações e ajuste dos intervalos de confiança para conglomerados. Resultados: A média de idade dos participantes foi de 12,57 (± 1,64) anos, dos quais 55,2% eram do sexo feminino. Encontraram-se 11,3% da amostra com níveis pressóricos alterados e 16,2% com valores limítrofes. Das variáveis antropométricas analisadas, a que demonstrou maior correlação com valores pressóricos aumentados foi o diâmetro do quadril (r = 0,462, p < 0,001) seguido de circunferência abdominal menor (r = 0,404, p < 0,001) e prega cutânea abdominal (r = 0,291, p < 0,001). Conclusão: Foi observada associação entre as circunferências da cintura e dobras cutâneas e níveis pressóricos aumentados nos escolares da amostra. Portanto, é de fundamental importância que a aferição da pressão arterial e as medidas de cintura e quadril sejam rotina nos serviços de saúde de forma precoce a fim de prevenir essa condição patológica.

Metabolic Syndrome and Importance of Associated Variables in Children and Adolescents in Guabiruba - SC, Brazil

Background:The risk factors that characterize metabolic syndrome (MetS) may be present in childhood and adolescence, increasing the risk of cardiovascular disease in adulthood.Objective:Evaluate the prevalence of MetS and the importance of its associated variables, including insulin resistance (IR), in children and adolescents in the city of Guabiruba-SC, Brazil.Methods:Cross-sectional study with 1011 students (6–14 years, 52.4% girls, 58.5% children). Blood samples were collected for measurement of biochemical parameters by routine laboratory methods. IR was estimated by the HOMA-IR index, and weight, height, waist circumference and blood pressure were determined. Multivariate logistic regression models were used to examine the associations between risk variables and MetS.Results:The prevalence of MetS, IR, overweight and obesity in the cohort were 14%, 8.5%, 21% and 13%, respectively. Among students with MetS, 27% had IR, 33% were overweight, 45.5% were obese and 22% were eutrophic. IR was more common in overweight (48%) and obese (41%) students when compared with eutrophic individuals (11%; p = 0.034). The variables with greatest influence on the development of MetS were obesity (OR = 32.7), overweight (OR = 6.1), IR (OR = 4.4; p ≤ 0.0001 for all) and age (OR = 1.15; p = 0.014).Conclusion:There was a high prevalence of MetS in children and adolescents evaluated in this study. Students who were obese, overweight or insulin resistant had higher chances of developing the syndrome.

Association between Functional Variables and Heart Failure after Myocardial Infarction in Rats

Background: Heart failure prediction after acute myocardial infarction may have important clinical implications. Objective: To analyze the functional echocardiographic variables associated with heart failure in an infarction model in rats. Methods: The animals were divided into two groups: control and infarction. Subsequently, the infarcted animals were divided into groups: with and without heart failure. The predictive values were assessed by logistic regression. The cutoff values predictive of heart failure were determined using ROC curves. Results: Six months after surgery, 88 infarcted animals and 43 control animals were included in the study. Myocardial infarction increased left cavity diameters and the mass and wall thickness of the left ventricle. Additionally, myocardial infarction resulted in systolic and diastolic dysfunction, characterized by lower area variation fraction values, posterior wall shortening velocity, E-wave deceleration time, associated with higher values of E / A ratio and isovolumic relaxation time adjusted by heart rate. Among the infarcted animals, 54 (61%) developed heart failure. Rats with heart failure have higher left cavity mass index and diameter, associated with worsening of functional variables. The area variation fraction, the E/A ratio, E-wave deceleration time and isovolumic relaxation time adjusted by heart rate were functional variables predictors of heart failure. The cutoff values of functional variables associated with heart failure were: area variation fraction < 31.18%; E / A > 3.077; E-wave deceleration time < 42.11 and isovolumic relaxation time adjusted by heart rate < 69.08. Conclusion: In rats followed for 6 months after myocardial infarction, the area variation fraction, E/A ratio, E-wave deceleration time and isovolumic relaxation time adjusted by heart rate are predictors of heart failure onset.

Variables Nanodatenmanagement für eingebettete Systeme

Magdeburg, Univ., Fak. für Informatik, Diss., 2012

Application of Fuzzy Variables for Systems of Management Decision Support

The following article describes an approach covering the variety of opinions and uncertainties of estimates within the chosen technique of decision support. Mathematical operations used for assessment of options are traced to operations of working with functions that are used for assessment of possible options of decision-making. Approach proposed could be used within any technique of decision support based on elementary mathematical operations. In this article the above-mentioned approach is described under analytical hierarchy process.

Approximations and asymptotic expansions for sums of heavy-tailed random variables

Magdeburg, Univ., Fak. für Mathematik, Diss., 2015

Spatial and temporal distribution of Pseudis minuta (Anura, Hylidae, Hylinae) and environmental variables related to its reproductive activity in Reserva Biológica do Lami, southern Brazil

We studied the reproductive biology of a population of Pseudis minuta Günther, 1858 from Reserva Biológica do Lami (30º 15' S; 51º 05' W), Porto Alegre, southern Brazil. We assessed the spatial and temporal distribution of individuals (males, females, juveniles) and explored potential relationships with environmental variables. Field activities encompassed bimonthly surveys in three semi-permanent ponds, each one during approximately two days and two nights, from August 2004 to July 2005. We recorded differences in the sites used by males, females and juveniles, with males occupying deeper and more distant places from the border. The temporal distributions of individuals, calling sites and amplectant pairs indicated that the reproductive activity of P. minuta is related to some of the studied abiotic factors. Calling males presented statistical differences in relation to non-calling males for all daily abiotic variables analyzed (air temperature, water temperature, relative humidity and rainfall), as well as to monthly temperature and rainfall. The number of active males, females and juveniles was influenced by at least one of the daily or monthly environmental variables analyzed. We conclude that the reproduction in this species is seasonal and may be partially determined by abiotic factors.

Variables efectives de l'empowerment

Aquest treball que porta per títol variables efectives de l’empowerment es el treball investigació del programa de doctorat Interuniversitari en Organització i Administració d’Empreses. El treball està composat per tres parts diferenciades. La primera part del treball consisteix amb el comentari de vint articles relacionats amb la motivació, el downsizing i l’empowerment. Els resums exposats han servit per establir els fonaments teòrics previs al model proposat de variables efectives d’empowerment. La segona part consisteix amb l’elaboració d’un article que resumeix les principals fonts consultades i proposa un model de classificació de les variables que poden contribuir a aconseguir amb èxit un procés d’empowerment. Les variables efectives es poden dividir en variables recíproques, variables unidireccionals, variables compartides i variables reflexives. La tercera part i amb l’objectiu de comprovar la validesa de model s’ha desenvolupat un qüestionari per mesurar l’estat de les variables anomenades efectives d’empowerment i la seva contribució amb l’èxit del procés. Es descriu l’eina desenvolupada, el tractament i la representació de les dades obtingudes. Finalment es pot trobar els primers resultats de la prova pilot realitzada per provar el model conceptual proposat.

Efficient knowledge retrieval to calibrate input variables in forest fire prediction

Forest fires are a serious threat to humans and nature from an ecological, social and economic point of view. Predicting their behaviour by simulation still delivers unreliable results and remains a challenging task. Latest approaches try to calibrate input variables, often tainted with imprecision, using optimisation techniques like Genetic Algorithms. To converge faster towards fitter solutions, the GA is guided with knowledge obtained from historical or synthetical fires. We developed a robust and efficient knowledge storage and retrieval method. Nearest neighbour search is applied to find the fire configuration from knowledge base most similar to the current configuration. Therefore, a distance measure was elaborated and implemented in several ways. Experiments show the performance of the different implementations regarding occupied storage and retrieval time with overly satisfactory results.

Identificació de variables d'estat del sistema costaner sensibles a la càrrega de nutrients

Projecte de recerca elaborat a partir d’una estada a la Napier University, Gran Bretanya, des d’octubre del 2006 a febrer del 2007. Els ecosistemes marins costaners són sistemes complexos, tant pel que fa a l’estructura de les comunitats que hi viuen com per la seva dinàmica, amb processos que impliquen múltiples escales d’espai i de temps. Aquesta complexitat natural s’ha incrementat al llarg de les darreres dècades com a conseqüència directa del creixement urbà al litoral. L’augment de població a les zones costaneres ha comportat no només un augment generalitzat en l’aport de nutrients inorgànics al mar, sinó també una forta intervenció sobre la línia de costa –construcció de ports, dics- i canvis en el moviment de les masses d’aigua. En aquest context, la interacció entre els factors turbulència-nutrients a la zona costanera pot ser clau per a millorar la nostra comprensió sobre el funcionament dels sistemes planctònics i, en darrer terme, per a derivar-ne mesures de gestió. A diferència de treballs experimentals previs, que adrecen els efectes de la turbulència i/o els nutrients sobre grups específics de plàncton, per avaluar la resposta conjunta de la comunitat necessitem paràmetres integradors, que relacionin diversos processos i donin una idea general de l’estat i funcionament de l’ecosistema. Durant l’estada de recerca alguns dels algoritmes que es fan servir per la costa escocesa van reformular-se i recalcular-se amb dades de la Mediterrània (dades procedents de la badia de Blanes i de la costa de Barcelona). Els resultats mostren una capacitat de resposta molt ràpida del plàncton als increments de nutrients, una variabilitat anual marcada (quant a diversitat d’organismes planctònics) i apunten el fòsfor com a principal limitant del creixement dels organismes en aquesta zona de la Mediterrània.

Official Central Bank Interventions in the Foreign Exchange Markets: A DCC Approach with Exogenous Variables

This paper assesses the impact of official central bank interventions (CBIs) on exchange rate returns, their volatility and bilateral correlations. By exploiting the recent publication of intervention data by the Bank of England, this study is able to investigate fficial interventions by a total number of four central banks, while the previous studies have been limited to three (the Federal Reserve, Bundesbank and Bank of Japan). The results of the existing literature are reappraised and refined. In particular, unilateral CBI is found to be more successful than coordinated CBI. The likely implications of these findings are then discussed.

Modelling Breaks and Clusters in the Steady States of Macroeconomic Variables

Macroeconomists working with multivariate models typically face uncertainty over which (if any) of their variables have long run steady states which are subject to breaks. Furthermore, the nature of the break process is often unknown. In this paper, we draw on methods from the Bayesian clustering literature to develop an econometric methodology which: i) finds groups of variables which have the same number of breaks; and ii) determines the nature of the break process within each group. We present an application involving a five-variate steady-state VAR.

Hàbits alimentaris en nens de 8 a 12 anys de la comarca d'Osona

Introducció: La dieta mediterrània és considerada un dels patrons alimentaris més saludables ja que diversos estudis epidemiològics mostren que protegeix front diverses malalties cròniques com ara les malalties cardiovasculars, la diabetis i alguns càncers. Malauradament al nostre país els patrons alimentaris estan canviant a conseqüència de la modernització de la societat i estan portant a l’allunyament del patró de dieta mediterrània. Això és especialment crític entre la població infantil i juvenil, fet que predisposa a que en un futur augmenti la prevalença de malalties cròniques entre la població adulta. Objectiu: avaluar els hàbits alimentaris i l’estat nutricional d’escolars de 8 a 12 anys de la comarca d’Osona. Mètodes: estudi de disseny observacional i transversal. La mostra estava constituïda per 191 escolars de 4rt i 5è d’ensenyança primària d’escoles de la comarca d’Osona. La informació sobre la dieta es va recollir a través d’una enquesta alimentària, un recordatori de 24 hores, un qüestionari de freqüència de consum alimentari i el test KIDMED. Les determinacions antropomètriques que es van realitzar van ser talla, pes, IMC (Índex de Massa Corporal), plec tricipital, perímetre braquial i perímetre abdominal. L’anàlisi estadística de totes les dades es va portar a terme mitjançant el programa estadístic SPSS per Windows versió 12.0. Resultats: quan es valora la qualitat de l’esmorzar, s’observa que només en el 16.8% dels casos la qualitat era bona, en el 68.6% dels casos la qualitat havia de millorar i en el 12.6% era de qualitat insuficient i en el 2.1% era de mala qualitat. També s’observa que la dieta que segueixen és desequilibrada quantitativament, concretament és baixa en hidrats de carboni, rica en greixos i lleugerament elevada en proteïnes. L’anàlisi qualitativa mostra que hi ha un molt baix consum de verdures i hortalisses i de fruita, mentre que s’arriba a les racions recomanades de carnis i d’olis i greixos. El test KIDMED mostra una puntuació mitjana de 7.21±1.96 punts, el que indica que la dieta de la població és de qualitat millorable. Pel que fa a l’estat nutricional s’observa que un 24,6% presenta valors de baix pes i un 17,8% sobrepès o obesitat, el que indica que un 42,4% de la població estudiada presenta un estat nutricional incorrecte. Conclusions: La dieta del col·lectiu estudiat s’allunya de les recomanacions de la SENC (Sociedad Española de Nutrición Comunitaria). Els resultats del test KIDMED indiquen que només un 44% de la població segueix un patró òptim de Dieta mediterrània i l’anàlisi de l’estat nutricional mostra que un 42,4% presenta un estat nutricional incorrecte, sigui per excés o per defecte de pes. Per tant, es fa necessari dissenyar estratègies d’educació alimentària adequades per millorar els hàbits alimentaris dels escolars i aconseguir en un futur un estat òptim de salut.

Using VARs and TVP-VARs with Many Macroeconomic Variables

This paper discusses the challenges faced by the empirical macroeconomist and methods for surmounting them. These challenges arise due to the fact that macroeconometric models potentially include a large number of variables and allow for time variation in parameters. These considerations lead to models which have a large number of parameters to estimate relative to the number of observations. A wide range of approaches are surveyed which aim to overcome the resulting problems. We stress the related themes of prior shrinkage, model averaging and model selection. Subsequently, we consider a particular modelling approach in detail. This involves the use of dynamic model selection methods with large TVP-VARs. A forecasting exercise involving a large US macroeconomic data set illustrates the practicality and empirical success of our approach.