867 resultados para Relationship quality


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The assessment of water quality has changed markedly worldwide over the last years, especially in Europe due to the implementation of the Water Framework Directive. Fish was considered a key-element in this context and several fish-based multi-metric indices have been proposed. In this study, we propose a multi-metric index, the Estuarine Fish Assessment Index (EFAI), developed for Portuguese estuaries, designed for the overall assessment of transitional waters, which could also be applied at the water body level within an estuary. The EFAI integrates seven metrics: species richness, percentage of marine migrants, number of species and abundance of estuarine resident species, number of species and abundance of piscivorous species, status of diadromous species, status of introduced species and status of disturbance sensitive species. Fish sampling surveys were conducted in 2006, 2009 and 2010, using beam trawl, in 13 estuarine systems along the Portuguese coast. Most of the metrics presented a high variability among the transitional systems surveyed. According to the EFAI values, Portuguese estuaries presented a "Good" water quality status (except the Douro in a particular year). The assessments in different years were generally concordant, with a few exceptions. The relationship between the EFAI and the Anthropogenic Pressure Index (API) was not significant, but a negative and significant correlation was registered between the EFAI and the expert judgement pressure index, at both estuary and water body level. The ordination analysis performed to evaluate similarities among North-East Atlantic Geographical Intercalibration Group (NEAGIG) fish-based indices put in evidence four main groups: the French index, since it is substantially different from all the other indices (uses only four metrics based on densities); indices from Ireland, United Kingdom and Spain (Asturias and Cantabria); the Dutch and German indices; and the indices of Belgium. Portugal and Spain (Basque country). The need for detailed studies, including comparative approaches, on several aspects of these assessment tools, especially in what regards their response to anthropogenic pressures was stressed. (C) 2011 Elsevier Ltd. All rights reserved.

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In most agroecosystems, nitrogen (N) is the most important nutrient limiting plant growth. One management strategy that affects N cycling and N use efficiency (NUE) is conservation agriculture (CA), an agricultural system based on a combination of minimum tillage, crop residue retention and crop rotation. Available results on the optimization of NUE in CA are inconsistent and studies that cover all three components of CA are scarce. Presently, CA is promoted in the Yaqui Valley in Northern Mexico, the country´s major wheat-producing area in which from 1968 to 1995, fertilizer application rates for the cultivation of irrigated durum wheat (Triticum durum L.) at 6 t ha-1 increased from 80 to 250 kg ha-1, demonstrating the high intensification potential in this region. Given major knowledge gaps on N availability in CA this thesis summarizes the current knowledge of N management in CA and provides insights in the effects of tillage practice, residue management and crop rotation on wheat grain quality and N cycling. Major aims of the study were to identify N fertilizer application strategies that improve N use efficiency and reduce N immobilization in CA with the ultimate goal to stabilize cereal yields, maintain grain quality, minimize N losses into the environment and reduce farmers’ input costs. Soil physical and chemical properties in CA were measured and compared with those in conventional systems and permanent beds with residue burning focusing on their relationship to plant N uptake and N cycling in the soil and how they are affected by tillage and N fertilizer timing, method and doses. For N fertilizer management, we analyzed how placement, time and amount of N fertilizer influenced yield and quality parameters of durum and bread wheat in CA systems. Overall, grain quality parameters, in particular grain protein concentration decreased with zero-tillage and increasing amount of residues left on the field compared with conventional systems. The second part of the dissertation provides an overview of applied methodologies to measure NUE and its components. We evaluated the methodology of ion exchange resin cartridges under irrigated, intensive agricultural cropping systems on Vertisols to measure nitrate leaching losses which through drainage channels ultimately end up in the Sea of Cortez where they lead to algae blooming. A throughout analysis of N inputs and outputs was conducted to calculate N balances in three different tillage-straw systems. As fertilizer inputs are high, N balances were positive in all treatments indicating the risk of N leaching or volatilization during or in subsequent cropping seasons and during heavy rain fall in summer. Contrary to common belief, we did not find negative effects of residue burning on soil nutrient status, yield or N uptake. A labeled fertilizer experiment with urea 15N was implemented in micro-plots to measure N fertilizer recovery and the effects of residual fertilizer N in the soil from summer maize on the following winter crop wheat. Obtained N fertilizer recovery rates for maize grain were with an average of 11% very low for all treatments.

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The Quality of life is currently a major topic discussed in our society. The World Health Organization (WHO) has been developing a unifying and transcultural definition of QOL. They considered it as 'the individual's perception of his or her position in life, within the cultural context and value system he or she lives in, and in relation to his or her goals, expectations, parameters and social relations. It is a broad ranging concept affected in a complex way by the person's physical health, psychological state, level of independence, social relationships and their relationship to salient features of their environment (WHOQOL, 1997, p. 1). Congenital heart disease is the most prevalent congenital disease in Portugal. Despite the advances in cardiac treatment and an early correct diagnosis that could increase the survival of children with congenital heart disease, this condition influences the quality of life of children, adolescents and their parents. Knowing the perception of quality of life could help healthcare professionals, nurses in particular, providing suited care to the needs of these families, establishing priorities in their interventions, sensing predictors of a poor quality of life, promoting adherence to treatment and boosting compliance with treatment, and fostering greater satisfaction for these children, adolescents and their parents. Purpose As part of broader research and with the awareness that the chronic conditions could impact the quality of life and considering that all advances on treating congenital cardiac diseases we have defined this main objective: To determine the quality of life in children and adolescents with congenital heart disease (CHD) and the perception of their parents, as well as factors that influence it. Methods It is a quantitative, descriptive and correlational research. The data collection tool was a questionnaire, which consisted of four parts: socio-demographic and educational characteristics, clinical characteristics, and quality of life, obtained using the Pediatric Cardiac Quality of Life Inventory - PCQLI - (Marino, Tomlinson, Wernovsky, Drotar , Newburger, Mahony et al., 2010) translated into Portuguese. Data collection took place between February and July 2014, in compliance with ethical research guidelines. The sample comprised 59 children, 59 parents of children, 80 adolescents and 80 parents of adolescents. Results The results indicated that children, adolescents, and their parents have high level of perceived health. The results are similar in all groups: children and parents and adolescents and parents. In the group of children, we observed the classification of "Good" in 66.10%, followed by the "Very Good" at 18.65% and "fair" in 15.25% of cases. The parents of the children responded in about half the cases that the health of their children was "good" (50.85%), "very good" in 30.51% "fair" in 11.86% and "Excellent "in 6.78%. In turn, the group of adolescents can be seen that 46.25% rate their health as "good", 32.50% as "very good", 16.25% as "Average" and 5% as "Excellent". Parents of teenagers classify the health of their children mostly as "good" in 42.50%, 31.25% as "very good", 20% as "fair" and 6.25% as "excellent". To point out that none of the respondents pointed out the option of a health status "Bad". About the quality of life, in general the results indicated that children, adolescents and their parents have high levels of quality of life, and that perceptions of parents and children are similar. Only in the children's group (8 to 12 years old), was no influence of socio-demographic, school or clinical variables on quality of life observed. For adolescents (13 to 18 years old), school, special education, school retention, the age of diagnosis of congenital heart disease, cardiac catheterization and surgical intervention influenced their quality of life. Perception of quality of life of parents of children and of adolescents was influenced by socio-demographic and clinical variables. The results partly agree with the literature in this field. About the influence of some variables: - The perception of quality of life expressed by children and adolescents with congenital heart disease and parents are related, with statistical significance. - There were no statistically significant relationships between the quality of life of children and adolescents and their age, gender or socioeconomic status. - Adolescents differ statistically significant between their quality of life and their education, the frequency of special education and the existence of grade retention. The severity of heart disease, the number of cardiac catheterizations or surgery and the presence of other health disorders are unrelated to the quality of life of children and adolescents. - Adolescents revealed that the level of quality of life is influenced by the age of diagnosis of CHD by cardiac catheterization and surgery. - For parents of children and adolescents gender and their education don´t influence their perception of quality of life. Only the socioeconomic status of parents of teens has statistically significant difference to quality of life. - Parents of children and adolescents do not show statistically significant relationship between the perceived level of quality of life and severity of disease, age at diagnosis, the number of surgical interventions and the existence of other health disorders. - There is a relationship of statistical significance between cardiac catheterization and the perceived quality of life by parents of adolescents; between the number of cardiac catheterizations and the perception of quality of life of parents of children; and between performing surgery and the perception of parents of children and adolescents. Conclusion To analyze the quality of life of children and adolescents with CHD must be a key focus of attention in caring for this population, allowing the identification of individual differences, interests, preferences, and prevent potential problems. The knowledge acquired along with clinical experience contributes to improve the quality of life of children and families, facilitating their growth, psycho-emotional development and social integration. Nevertheless, the reading and interpretation of these results must be prudent and cautious, there are limitations to this research, including: the use of a range of specific quality of life for the Congenital heart disease in children, adolescents, and parents but whose validation process could not be completed in this study; the low prevalence of severe conditions in our sample; the absence of national studies to enable comparison with the results obtained. We intend to continue the process of validation of instrument and enlarge the research to Lisbon and Oporto, other major centers where the cardiac conditions can be treated

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Purpose: The Quality of life is currently a major topic discussed in our society. The World Health Organization (WHO) has been developing a unifying and transcultural definition of QOL. They considered it as 'the individual's perception of his or her position in life, within the cultural context and value system he or she lives in, and in relation to his or her goals, expectations, parameters and social relations. It is a broad ranging concept affected in a complex way by the person's physical health, psychological state, level of independence, social relationships and their relationship to salient features of their environment (WHOQOL, 1997, p. 1). Congenital heart disease is the most prevalent congenital disease in Portugal. Despite the advances in cardiac treatment and an early correct diagnosis that could increase the survival of children with congenital heart disease, this condition influences the quality of life of children, adolescents and their parents. Knowing the perception of quality of life could help healthcare professionals, nurses in particular, providing suited care to the needs of these families, establishing priorities in their interventions, sensing predictors of a poor quality of life, promoting adherence to treatment and boosting compliance with treatment, and fostering greater satisfaction for these children, adolescents and their parents. 'As part of broader research and with the awareness that the chronic conditions could impact the quality of life and considering that all advances on treating congenital cardiac diseases we have defined this main objective: To determine the quality of life in children and adolescents with congenital heart disease (CHD) and the perception of their parents, as well as factors that influence it. Methods: It is a quantitative, descriptive and correlational research. The data collection tool was a questionnaire, which consisted of four parts: socio-demographic and educational characteristics, clinical characteristics, and quality of life, obtained using the Pediatric Cardiac Quality of Life Inventory ? PCQLI - (Marino, Tomlinson, Wernovsky, Drotar , Newburger, Mahony et al., 2010) translated into Portuguese. Data collection took place between February and July 2014, in compliance with ethical research guidelines. The sample comprised 59 children, 59 parents of children, 80 adolescents and 80 parents of adolescents. Results: The results indicated that children, adolescents, and their parents have high level of perceived health. The results are similar in all groups: children and parents and adolescents and parents. In the group of children, we observed the classification of "Good" in 66.10%, followed by the "Very Good" at 18.65% and "fair" in 15.25% of cases. The parents of the children responded in about half the cases that the health of their children was "good" (50.85%), "very good" in 30.51% "fair" in 11.86% and "Excellent "in 6.78%. In turn, the group of adolescents can be seen that 46.25% rate their health as "good", 32.50% as "very good", 16.25% as "Average" and 5% as "Excellent". Parents of teenagers classify the health of their children mostly as "good" in 42.50%, 31.25% as "very good", 20% as "fair" and 6.25% as "excellent". To point out that none of the respondents pointed out the option of a health status "Bad". About the quality of life, in general the results indicated that children, adolescents and their parents have high levels of quality of life, and that perceptions of parents and children are similar. Only in the children?s group (8 to 12 years old), was no influence of socio-demographic, school or clinical variables on quality of life observed. For adolescents (13 to 18 years old), school, special education, school retention, the age of diagnosis of congenital heart disease, cardiac catheterization and surgical intervention influenced their quality of life. Perception of quality of life of parents of children and of adolescents was influenced by socio-demographic and clinical variables. The results partly agree with the literature in this field. About the influence of some variables: The perception of quality of life expressed by children and adolescents with congenital heart disease and parents are related, with statistical significance. There were no statistically significant relationships between the quality of life of children and adolescents and their age, gender or socioeconomic status. Adolescents differ statistically significant between their quality of life and their education, the frequency of special education and the existence of grade retention. The severity of heart disease, the number of cardiac catheterizations or surgery and the presence of other health disorders are unrelated to the quality of life of children and adolescents. Adolescents revealed that the level of quality of life is influenced by the age of diagnosis of CHD by cardiac catheterization and surgery. For parents of children and adolescents gender and their education don?t influence their perception of quality of life. Only the socioeconomic status of parents of teens has statistically significant difference to quality of life. Parents of children and adolescents do not show statistically significant relationship between the perceived level of quality of life and severity of disease, age at diagnosis, the number of surgical interventions and the existence of other health disorders. There is a relationship of statistical significance between cardiac catheterization and the perceived quality of life by parents of adolescents; between the number of cardiac catheterizations and the perception of quality of life of parents of children; and between performing surgery and the perception of parents of children and adolescents. Conclusion: To analyze the quality of life of children and adolescents with CHD must be a key focus of attention in caring for this population, allowing the identification of individual differences, interests, preferences, and prevent potential problems. The knowledge acquired along with clinical experience contributes to improve the quality of life of children and families, facilitating their growth, psycho-emotional development and social integration. Nevertheless, the reading and interpretation of these results must be prudent and cautious, there are limitations to this research, including: the use of a range of specific quality of life for the Congenital heart disease in children, adolescents, and parents but whose validation process could not be completed in this study; the low prevalence of severe conditions in our sample; the absence of national studies to enable comparison with the results obtained. We intend to continue the process of validation of instrument and enlarge the research to Lisbon and Oporto, other major centers where the cardiac conditions can be treated.

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The relationship between the themes of Total Quality Management (TQM) and Social Responsibility (CSR) through the concepts, approaches and models of excellence is a reality of sustainable and stable companies. Being organizations, people, act correctly and rightly do in society go through a quality management and social responsibility thereof. It is based on these two philosophies (Total Quality Management and Corporate Social Responsibility), which developed this literature review work, essentially based on a relational analysis in two papers, namely: "TQM and CSR Nexus" by Ghobadian et al. (2007) and "The Corporate Social Responsibility Audit Within the Quality Management Framework," de Kok et al. (2001) and applied to an organizational situation in concrete: the Nabeiro Delta Cafés Group - SGPS, SA.

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The purpose of this study was to identify the quality of life profile, overweight-obesity and sedentary behavior in a group of elementary and high school children of Guanacaste. 635 students participated in the study. The participants completed a protocol by which they were anthropometrically evaluated, and also filled up a questionnaire related to sedentary behavior and quality of life. In general, the findings reflected a prevalence of overweight and obesity of 13, 9%. The most important sedentary activities were, in descending order, the small screen (watching TV, video games, computer), and certain social and cultural activities. The self-reported quality of life index was within acceptable limits but not exceeding 80 points on a scale of 1-100. There was no significant relationship between the rate of the overall quality of life, overweight, obesity and some sedentary behaviors, although some anthropometric parameters like percentage of body fat and body weight showed significant correlation with sedentary behavior and specific aspects belonging to quality of life. The study provides valuable information to health authorities, directors of educational institutions and parents about key issues related to child development.

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The aim of this thesis is to explore the possible influence of the food matrix on food quality attributes. Using nuclear magnetic resonance techniques, the matrix-dependent properties of different foods were studied and some useful indices were defined to classify food products based on the matrix behaviour when responding to processing phenomena. Correlations were found between fish freshness indices, assessed by certain geometric parameters linked to the morphology of the animal, i.e. a macroscopic structure, and the degradation of the product structure. The same foodomics approach was also applied to explore the protective effect of modified atmospheres on the stability of fish fillets, which are typically susceptible to oxidation of the polyunsaturated fatty acids incorporated in the meat matrix. Here, freshness is assessed by evaluating the time-dependent change in the fish metabolome, providing an established freshness index, and its relationship to lipid oxidation. In vitro digestion studies, focusing on food products with different matrixes, alone and in combination with other meal components (e.g. seasoning), were conducted to investigate possible interactions between enzymes and food, modulated by matrix structure, which influence digestibility. The interaction between water and the gelatinous matrix of the food, consisting of a network of protein gels incorporating fat droplets, was also studied by means of nuclear magnetic relaxometry, in order to create a prediction tool for the correct classification of authentic and counterfeit food products protected by a quality label. This is one of the first applications of an NMR method focusing on the supramolecular structure of the matrix, rather than the chemical composition, to assess food authenticity. The effect of innovative processing technologies, such as PEF applied to fruit products, has been assessed by magnetic resonance imaging, exploiting information associated with the rehydration kinetics exerted by a modified food structure.

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The ecosystem services provided by bees are very important. Factors as habitat fragmentation, intensive agriculture and climate change are contributing to the decline of bee populations. The use of remote sensing could be a useful tool for the recognition of sites with a high diversity, before performing a more expensive survey in the field. In this study the ability of Unmanned Aerial Vehicles (UAV) images to estimate biodiversity at local scale has been analysed testing the concept of the Height Variation Hypothesis (HVH). This approach states that, the higher the vegetation height heterogeneity (HH) measured by remote sensing information, the higher the vertical complexity and the higher vegetation species diversity. In this thesis the concept has been brought to a higher level, in order to understand if the vegetation HH can be considered a proxy also of bee species diversity and abundance. We tested this approach collecting field data on bees/flowers and RGB images through an UAV campaign in 30 grasslands in the South of the Netherlands. The Canopy Height Model (CHM) were derived through the photogrammetry technique "Structure from Motion" (SfM) with resolutions of 10cm, 25cm, 50cm. Successively, the HH assessed on the CHM using the Rao's Q heterogeneity index was correlated to the field data (bee abundance, diversity and bee/flower species richness). The correlations were all positive and significant. The highest R2 values were found when the HH was calculated at 10cm and correlated to bee species richness (R2 = 0.41) and Shannon’s H index (R2 = 0.38). Using a lower spatial resolution the goodness of fit slightly decreases. For flower species richness the R2 ranged between 0.36 to 0.39. Our results suggest that methods based on the concept behind the HVH, in this case deriving information of HH from UAV data, can be developed into valuable tools for large-scale, standardized and cost-effective monitoring of flower diversity and of the habitat quality for bees.

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The aim was to evaluate the relationship between orofacial function, dentofacial morphology, and bite force in young subjects. Three hundred and sixteen subjects were divided according to dentition stage (early, intermediate, and late mixed and permanent dentition). Orofacial function was screened using the Nordic Orofacial Test-Screening (NOT-S). Orthodontic treatment need, bite force, lateral and frontal craniofacial dimensions and presence of sleep bruxism were also assessed. The results were submitted to descriptive statistics, normality and correlation tests, analysis of variance, and multiple linear regression to test the relationship between NOT-S scores and the studied independent variables. The variance of NOT-S scores between groups was not significant. The evaluation of the variables that significantly contributed to NOT-S scores variation showed that age and presence of bruxism related to higher NOT-S total scores, while the increase in overbite measurement and presence of closed lip posture related to lower scores. Bite force did not show a significant relationship with scores of orofacial dysfunction. No significant correlations between craniofacial dimensions and NOT-S scores were observed. Age and sleep bruxism were related to higher NOT-S scores, while the increase in overbite measurement and closed lip posture contributed to lower scores of orofacial dysfunction.

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Muscle strength and functional independence are considered to be determinants of frailty levels among elderly people. The aim here was to compare lower-limb muscle strength (LLMS) with functional independence in relation to sex, age and number of frailty criteria, and to ascertain the influence of these variables on elderly outpatients' independence. Quantitative cross-sectional study, in a tertiary hospital. The study was conducted on 150 elderly outpatients of both sexes who were in a cognitive condition allowing oral communication, between October 2005 and October 2007. The following instruments were used: five-times sit-to-stand test (FTSST), Functional Independence Measurement (FIM) and Lawton's Instrumental Activities of Daily Living Scale (IADL). Descriptive, comparative, multivariate, univariate and Cronbach alpha analyses were performed. The mean time taken in the FTSST was 21.7 seconds; the mean score for FIM was 82.2 and for IADL was 21.2; 44.7% of the subjects presented 1-2 frailty criteria and 55.3% > 3 criteria. There was a significant association between LLMS and functional independence in relation to the number of frailty criteria, without homogeneity regarding sex and age. Functional independence showed significant influence from sex and LLMS. Elderly individuals with 1 or 2 frailty criteria presented greater independence in all FTSST scores. The subjects with higher LLMS presented better functional independence.

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This study sought to evaluate the association between the impact of oral disorders in terms of physical/psychosocial dimensions and quality of life among the elderly. It involved a cross-sectional study conducted among the elderly (65-74 years) in 2008/2009. The social impact was assessed using the Oral Health Impact Profile (OHIP 14) and the quality of life using the SF 12 Short-Form Health Survey. Descriptive, univariate and multivariate (logistic regression) analysis was conducted with correction for the design effect, using SPSS(r)18.0 software. Of the 800 individuals approached, 736 elderly individuals participated (TR = 92%), with a mean age of 67.77 years, the majority of whom showed no impact based on the measurement of the prevalence of OHIP. The functional limitation dimension of the OHIP was associated with the physical domain of the SF12, irrespective of the other variables investigated. However, the seriousness of OHIP and its psychological discomfort and disability dimensions was associated with the mental domain of the SF12. The conclusion reached is that some impacts of oral disorders were associated with unsatisfactory quality of life in the physical and mental domains.

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To assess quality of care of women with severe maternal morbidity and to identify associated factors. This is a national multicenter cross-sectional study performing surveillance for severe maternal morbidity, using the World Health Organization criteria. The expected number of maternal deaths was calculated with the maternal severity index (MSI) based on the severity of complication, and the standardized mortality ratio (SMR) for each center was estimated. Analyses on the adequacy of care were performed. 17 hospitals were classified as providing adequate and 10 as nonadequate care. Besides almost twofold increase in maternal mortality ratio, the main factors associated with nonadequate performance were geographic difficulty in accessing health services (P < 0.001), delays related to quality of medical care (P = 0.012), absence of blood derivatives (P = 0.013), difficulties of communication between health services (P = 0.004), and any delay during the whole process (P = 0.039). This is an example of how evaluation of the performance of health services is possible, using a benchmarking tool specific to Obstetrics. In this study the MSI was a useful tool for identifying differences in maternal mortality ratios and factors associated with nonadequate performance of care.

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The aim of this study was to assess the quality of diet among the elderly and associations with socio-demographic variables, health-related behaviors, and diseases. A population-based cross-sectional study was conducted in a representative sample of 1,509 elderly participants in a health survey in Campinas, São Paulo State, Brazil. Food quality was assessed using the Revised Diet Quality Index (DQI-R). Mean index scores were estimated and a multiple regression model was employed for the adjusted analyses. The highest diet quality scores were associated with age 80 years or older, Evangelical religion, diabetes mellitus, and physical activity, while the lowest scores were associated with home environments shared with three or more people, smoking, and consumption of soft drinks and alcoholic beverages. The findings emphasize a general need for diet quality improvements in the elderly, specifically in subgroups with unhealthy behaviors, who should be targeted with comprehensive strategies.

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This paper examines the spatial pattern of ill-defined causes of death across Brazilian regions, and its relationship with the evolution of completeness of the deaths registry and changes in the mortality age profile. We make use of the Brazilian Health Informatics Department mortality database and population censuses from 1980 to 2010. We applied demographic methods to evaluate the quality of mortality data for 137 small areas and correct for under-registration of death counts when necessary. The second part of the analysis uses linear regression models to investigate the relationship between, on the one hand, changes in death counts coverage and age profile of mortality, and on the other, changes in the reporting of ill-defined causes of death. The completeness of death counts coverage increases from about 80% in 1980-1991 to over 95% in 2000-2010 at the same time the percentage of ill-defined causes of deaths reduced about 53% in the country. The analysis suggests that the government's efforts to improve data quality are proving successful, and they will allow for a better understanding of the dynamics of health and the mortality transition.

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Ant foraging on foliage can substantially affect how phytophagous insects use host plants and represents a high predation risk for caterpillars, which are important folivores. Ant-plant-herbivore interactions are especially pervasive in cerrado savanna due to continuous ant visitation to liquid food sources on foliage (extrafloral nectaries, insect honeydew). While searching for liquid rewards on plants, aggressive ants frequently attack or kill insect herbivores, decreasing their numbers. Because ants vary in diet and aggressiveness, their effect on herbivores also varies. Additionally, the differential occurrence of ant attractants (plant and insect exudates) on foliage produces variable levels of ant foraging within local floras and among localities. Here, we investigate how variation of ant communities and of traits among host plant species (presence or absence of ant attractants) can change the effect of carnivores (predatory ants) on herbivore communities (caterpillars) in a cerrado savanna landscape. We sampled caterpillars and foliage-foraging ants in four cerrado localities (70-460 km apart). We found that: (i) caterpillar infestation was negatively related with ant visitation to plants; (ii) this relationship depended on local ant abundance and species composition, and on local preference by ants for plants with liquid attractants; (iii) this was not related to local plant richness or plant size; (iv) the relationship between the presence of ant attractants and caterpillar abundance varied among sites from negative to neutral; and (v) caterpillars feeding on plants with ant attractants are more resistant to ant predation than those feeding on plants lacking attractants. Liquid food on foliage mediates host plant quality for lepidopterans by promoting generalized ant-caterpillar antagonism. Our study in cerrado shows that the negative effects of generalist predatory ants on herbivores are detectable at a community level, affecting patterns of abundance and host plant use by lepidopterans. The magnitude of ant-induced effects on caterpillar occurrence across the cerrado landscape may depend on how ants use plants locally and how they respond to liquid food on plants at different habitats. This study enhances the relevance of plant-ant and ant-herbivore interactions in cerrado and highlights the importance of a tritrophic perspective in this ant-rich environment.