20 resultados para Seca severa

em Universidade Federal do Rio Grande do Norte(UFRN)


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The artifi cial eutrophication is one of the biggest t h reat for the quality of aquatic ecosystems in the whole world. The expectations for the future climatic scenarios in arid and semi - arid regions are intense and frequent droughts enhancing the risk of eutrophicati on and cyanobacterial blooms. Restoration techniques of eutrophic lakes were proposed to reduce nutrient loading and improve the water quality. A successful technique used in temperate regions is the biomanipulation by benthivorous fish removal . Our hypoth esis is that the benthivorous fish removal reduces phytoplankton total biomass and change the composition of phytoplankton functional groups, improving water quality. The aim of the study was evaluate the impact of biomanipulation on phytoplankton function al groups and in the water quality. We applied the technique of biomanipulation in the artificial lake ESEC, in a semi - arid region of Brazil and analyzed the physical and chemical variables and the dynamic of phytoplankton functional groups monthly during November 2012 to August 2013. With the removal of benthivorous fish we observed a significant increase of the euphotic depth, phytoplankton richness and the recruitment of green algae (groups F and J ), indicators of good water quality. However, we did not observe significant differences on total phosphorous concentration and on phytoplankton biomass and diversity. The drought effect in the region during the study was evident , promoting a drastic reduction on water level which influenced the availability of resource and affected phytoplankton community before the biomanipulation. To evaluate the effect of severe drought on the dynamic of phytoplankton functional groups and test if the drought periods are favorable to dominance of cyanobacterial groups, we stu died two artificial neighbors lakes (ESEC and Pocinhos) in a semi - arid tropical region during May 2012 to February 2013. We observed a temporal differentiation of biotic and abiotic variables caused by drought. Both lakes presented reduction of 2 meters of water level and increase on conductivity, turbidity, nutrients concentration and a reduction on water transparency, during the severe drought. The deeper lake (Pocinhos) increased phytoplankton total biomass and presented cyanobacterial functional group d ominance (group S N ) and the shallower lake (ESEC) reduced phytoplankton total biomass and presented dominance of mixotrophic and flagellate functional groups (groups W 1 e W 2 ). Summarizing, the knowledge of the effects of benthivorous fish removal in semi - a rid tropical lakes still unknown and this study had limitations caused by the impact of drought. Thus, it is necessary a long term monitoring to investigate the real effects of biomanipulation on the functioning of the studied ecosystems. Otherwise, period s of drought could have opposite effects (increase or reduction) on total biomass and composition of phytoplankton functional groups. Drought not always leads to dominance of cyanobacterial groups.

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Reservoirs are the main sources of surface water in Brazil´s semiarid region. The majority of these water supplies, however, are compromised by eutrophication. A severe drought in 2012 contributed to significant losses in water volume, influencing the availability of resources (nutrients and light) for phytoplankton. The aim of this study is to understand the dynamics of the functional groups of phytoplankton and the factors that affect them during a severe drought in the semiarid reservoirs of the northeast. We therefore studied the Dourado, Gargalheiras and Passagem das Traíras reservoirs in Rio Grande do Norte from January 2012 to January 2013. The effect of drought favoured homogeneity within the reservoir, in relation to biotic and abiotic variables, notably the absence of water supply given the lack of flow from its tributaries (intermittent river). The phytoplankton functional groups of bloomforming cyanobacteria (SN, S1 and M) dominated throughout the year 2012, in both the shallow and deep areas of the three reservoirs studied. The groups were related to high concentrations of volatile solids, total phosphorus and ammonia, and high turbidity. Cylindrospermopsis raciborskii (SN group) was the species with the greatest biomass in the three reservoirs. M group (Sphaerocavum brasiliense) performed better in shallow waters with more available phosphorus. Our data showed that high concentrations of nutrients and low availability of light, besides the stability of the water column due to lack of flow and the system´s high residence time, favoured the dominance of bloom-forming cyanobacteria groups, especially those tolerant to shadow

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Human activities alter soil features, causing the deterioration of its quality. Land use and occupation in drainage basins of water supply reservoirs can change the environmental soil quality and, thus, lead to the expansion of the soil potential of being a diffuse pollution source. In the Brazilian semiarid region, the soils are generally shallow with high susceptibility to erosion, favoring the sediment and nutrients input into the superficial waterbodies, contributing to the eutrophication process. Moreover, this region has high temperatures and high evapotranspiration rates, that are generally higher than the precipitation rates, causing a negative hydric balance and big volume losses by evaporation. The water volume reduction increases the nutrients’ concentration and, therefore, exacerbates the eutrophication process, deteriorating the water quality. Thereby, we hypothesized that the eutrophication process of semiarid reservoirs is intensified both by the extreme climatic events of prolonged drought, and by the diffuse pollution due to the basin land use and occupation. The study aimed to test whether the land use and occupation activities of the basin and the severe drought events intensify the eutrophication process of a semiarid tropical reservoir. To verify the influence of human activities carried out in the water supply of drainage basin on the soil quality and the eutrophication process, we conducted the mapping of the kind of use and occupation, as well the calculation of erosion for each activity and the soil quality evaluation of the riparian zone and water quality of the water supply. For the water analyses, the samplings were carried out monthly in the deeper point, near dam. For the soil, deformed composite samples were taken for the physical and chemical attributes analysis, according to the identified land use and occupation classes. The results showed that extreme droughts drastically reduces the water volume and elevates the nutrients concentration, contributing, thus, to a bigger degradation of water quality. Furthermore, we verified that human activities in the drainage basin promote the diffuse pollution, by increasing the soil susceptibility to erosion and nutrients contents. Summarizing, our results support the investigated hypothesis that activities of land use and occupation and extreme drought generate a combined effect that provide the intensification of eutrophication process of semiarid reservoirs.

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The main consequence of eutrophication is an increase in algal biomass, mainly cyanobacterial blooms. The high evaporation and low precipitation, characteristics of semiarid regions, contribute to the nutrients availability increase in drought periods and consequent aggravation of eutrophic condition in reservoirs. Climate changes tend to intensify eutrophication symptoms, mostly in a semiarid region. Therefore, the aim of this study was to evaluate the impact of an extended drought in algal biomass in Parelhas’s Boqueirão, a mesotrophic reservoir located in a semiarid tropical region. The low volume was associated to water quality degradation and to the high nutrients concentrations and low water transparency. The increase in nutrients availability in the water column, consequence of reduced precipitation and low reservoir’s volume, provided the necessary resources for algal growth and allowed a change in trophic state in Boqueirão reservoir. This study showed how an extended drought decreases water quality. The effect of drought in Boqueirão was late detected due to the reservoir´s low initial nutrients concentration. The reservoir´s volume reduction increased the nutrient availability along with the algal biomass increase and the reservoir´s trophic state change of mesotrophic to eutrophic.

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The potentially toxic cyanobacterial blooms in water bodies are spread across the globe, resulting in the loss of water quality and adverse effects on human health. In arid and semiarid regions, the hydrologic regime characterized by an annual cycle of drought and rain, change the volume and the retention time of the reservoir. Such changes affect the limnological characteristics and causing changes in composition and biomass community of cyanobacteria. The reservoir Cruzeta (Zmax = 8.7 m) is a eutrophic water supply source located in the semiarid tropical (Northeast Brazil). Raised the hypothesis that the hydrological regime of semi-arid tropical is a determining factor in the availability of resources in eutrophic water sources, which influences the composition of dominant species of cyanobacteria. The aim of this study was to analyze the changes in biomass and species composition of cyanobacteria for two annual hydrological cycles and evaluate factors drivers. The study was divided into five distinct periods (dry 2010, rain 2011, dry 2011, rain 2012, dry 2012). The dominant group found in all periods was Cyanobacteria (99% of total biomass), which contributed to the low diversity. The filamentous species Cylindrospermopsis raciborskii was present at both points in almost every study. The colonial species Microcystis panniformis and Sphaerocavum brasiliensis dominated only in periods with lower volumes of water. The diatoms contribute more to the biomass during the period of severe drought. The point near the dam (P1) had phytoplankton biomass larger than the point near the tributary (P2). The dominant species of colonial cyanobacteria lasted until the overflow in P1, and P2 this dominance was until the first rains. The redundancy analysis indicated that physical factors such as light availability and water level were the main factors driving the seasonal succession of phytoplankton. The composition of phytoplankton in spring was alternated by species of filamentous cyanobacteria in conditions of poor stability of the water column, such as Cylindrospermopsis raciborskii, and colonial species under conditions of high stability of the water column, such as Microcystis panniformis and Sphaerocavum brasiliensis. The extremes of torrential rains and severe droughts, governed by the hydrological regime of the semi-arid region led to the availability of resources in the watershed, directing the spatial and temporal dynamics of phytoplankton in the reservoir Cruzeta

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Reservoirs are artificial ecosystems, intermediate between rivers and lakes, with diferent morphological and hydrological characteristics that can provide many important benefits to society. However, the use of this water for human consumption, watering livestock, leisure, irrigated agricultural production and pisciculture development, directly influence the increase loading of nutrients to aquatic environments and contribute to acceleration of eutrophication. Furthermore, global climate models are predicting a higher occurrence of extreme events such as floods and severe droughts, which will create hydrological stresses in lakes. In the semiarid northeast we can see the occurrence of these events, the drought of the years 2012, 2013 and 2014 was the worst drought in 60 years, according to the National Water Agency (ANA). Thus, this study aimed to evaluate the quality of the semiarid tropical water sources, identifying temporal patterns in periods with extreme hydrological events (floods and severe droughts). The study results showed that Gargalheiras and Cruzeta reservoirs presented significative changes in the limnological variables between rain and severe drought periods, with better appearance and in the most of the water quality variables in the rainy season and higher nutrientes concentrations and high electrical conductivity values in severe season, indicating decay of its quality. However, we found diferent behaviors between the reservoirs in severe drought. While Gargalheiras showed a typical behavior of the region, with high concentrations of algal biomass, indicating the worsening eutrophication, Cruzeta demonstrated a colapse in the total phytoplankton biomass, evidenced by the decrease in chla concentrations. This fact occurred because the low depth and proximity with the sediment facilited the inorganic solids resuspension and, consequently, resulted in turbid water column and light by limitation. In addition, the different behaviors between the reservoirs indicate that the responses of these environments problems such as extreme events must take into account factors such the region climate, size, depth of the reservoir and the basin characteristics.

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FREIRE, Isa Maria, et al. Ampliando o acesso livre a informaçao: a digitalizaçao do acervo do Nucleo Tematico da Seca. Pesquisa Brasileira em Ciência da Informação e Biblioteconomia, v.3, n.2, p. 137-142, 2008.Disponivel em: . Acesso em: 04 nov. 2010.

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CARVALHO, Monica Marques; CARVALHO, Luciana Moreira; FREIRE, I.M. A digitalizaçao do acervo do nucleo tematico da seca da UFRN como possibilidade de socializaçao da informaçao. Interface, v.1, n.1, 2004.Disponivel em: http://www.ccsa.ufrn.br/interface/1-1/artigos.htm. Acesso em: 04 nov.2010.

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CARVALHO, R.P.F. Núcleo Temático da SECA/UFRN: uso do acervo informacional. 1998. Dissertação (Mestrado)- Programa de Pós-Graduação em Ciência da Informação, Centro de Ciências Sociais e Aplicadas, Universidade Federal da Paraíba, João Pessoa, 1998.

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To determine whether there is familiar aggregation of severe preeclampsia in a Brazilian population from Rio Grande do Norte and to characterize the maternal and perinatal outcomes in the studied population. Methods: A case control study was performed with 412 participants who were admitted at Maternidade Escola Januário Cicco (MEJC) for medical care. Of these, 264 subjects presented normal blood pressure and 148 were cases. Cases were composed of eclampsia (n=47), HELLP Syndrome (n=85) and Eclampsia associated with HELLP syndrome (n=16). The diagnosis of these illness were based on the citeria developed by National High Blood Pressure Education Program Working (2000). An interview was performed with each subject and questions related to personal and familiar history of hypertension, preeclampsia, HELLP syndrome and eclampsia. Statistical analysis was performed and comparison of median and mean between cases and controls were performed, with the level of significance of 5%. The Odds-Ratio was determined to estimate the risk of preeclampsia within the families. Results: There were no difference in the demographic data between cases and controls. Previous history of chronic hypertension and preeclampsia was more frequent in the case group. Headaches were more frequent in eclampsia and epigastric pain in the HELLP syndrome cases. Bleeding and oliguria were more frequently found in the eclampsia associated with HELLP syndrome cases. Acute Renal insufficiency was a common complication in the case group, but these cases did not evolve to chronic renal insufficiency. The maternal mortality was 0.4% and the perinatal mortality was high, 223 per 1,000 live births. The 111 risk of a woman to develop preeclampsia whose mother has hypertension or had preeclampsia was respectively 2.5 and 3.5. This risk was increased 5 times, when a sibling has hypertension and 6 times when both sibling and mother had previous history of preeclampsia. Conclusions: This study confirms that there is familiar aggregation of preeclampsia in this Brazilian population. The potential for cardiovascular complications due to development of chronic hypertension indicates the need of closely follow up of women who develop preeclampsia

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This dissertation work is an effort to understand how the ideology and the power interferes in the signification of the speeches immersed in the context of the printed media concerning the drought in the Northeast of Brazil, weather occurrence that punishes 23 million of Brazilians, with all sort of problems. It also has specific concern about the everyday usage of the language and with the routines of the information production, without losing of sight the role of History in the formation of the identity of individuals and people. The research work is also developed in an interdisciplinary environment, applying to the formed corpus five articles from Folha de São Paulo , collected from January to July of 2005, the French Analysis method of the Speech and the theory of the polyphony of Bakhtin, in the Applied Linguistics area, accomplished with Communication beddings as the agenda-setting. The results ended to a good understanding about the ideology and power´s influence and chaining in the speeches formations as well as to comprehend peoples concept in an environment of almost-mediated interaction, bringing a media look about polyphony in the bakhtinian mold, besides showing how all these questions interferes with the half-barren the Northeast media´s vision on the subject

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The great droughts re- produced spaces in the city of Mossoró / RN in the end of the nineteenth century to the beginning of the twentieth century. Its dimension exceeds the climatic effects becoming social locus when advances over the political and economic sectors, social and cultural of the North / Northeast Brazilian societies during that period. This way, analyzing the re-production of social space in episodes of Mossoró‟s droughts is our toil. So try to reveal each segment, route and aspect of production of space in its size and interface between the perceived, conceived and lived, and subjects related to it - refugees, population and authorities - during the droughts of 1877, 1903 and 1915 within Mossoró city. Therefore, issues such as the constitution and representation of the city and social space in the terrifying experience of the drought of 1877, the production of fixed objects and flows of the urban web through of migrant labor, attempts to control, discipline and spatial planning and ways to resistance to these charges in daily sphere are key issues addressed in this work. For this we use diverse sources as minutes of the city council, reports from provincial presidents, media, memory books and others that sustain us in building our narrative and problematic. This way, the spatial production of Mossoró‟s droughts reveals itself in the field of relations and political-economic transformations and sociocultural, inextricably, that shapes and mobilizes your own social space

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INTRODUCTION: The high sensitivity C-reactive protein (hsCRP) constitutes an inflammatory mediator used as predictor of cardiovascular risk that comes being researched as indicative relation factor between cardiovascular and periodontal diseases. PROPOSITION: To compare serumals levels of C-reactive protein between patients with and without generalized severe chronic periodontitis. METHODOLOGY: A seccional study was realized using a sample with 62 patients, being 31 participants carriers of periodontal diseases (Group I) and 31 without periodontal diseases (Group II), grouped to the pairs by age and sex. As inclusion criterio were selected patients with diagnosis of generalized severe chronic periodontitis, being preculeds, individuals which presented systemic disease, recent infection history, historical of CVA or stroke, smokers, pregnants and lactants. The research consisted of two stages, a clinc and other biochemist. The clinical stage is constituted of periodontal examination and the biochemist stage, of the peripheral blood collection for determination hsCRP levels and a hemogram to inquire any panel which could suggest infectious and/or inflammatory process. RESULTS: Periodontal disease group presented a average of 0,36mg/dL, while the group without disease presented 0,17 mg/dL, do not existing significant difference statistically between the averages (p = 0,061). The cardiovascular risk for the group I was classified high for 27,6% of participants and low for 72,4% of them. In the group II, 6,45% presented high risk e 93,5% low risk, being this significant relation statistically gotten for Fisher s Test (p = 0,042) presenting OR = 5,33; IC = 95% (1,02 27,4). The independets variables reseacred do not presented significant association statistically with the levels of hsCRP. CONCLUSION: The study indicated that despite of carriers patients of periodontal diseases do not present differents serumals levels of hsCRP from the other group, the periodontal disease was considered as risk factor for hsCRP plasmatic levels elevation

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The low quality of tropical pastures in the dry season justifies the use of dietary supplements to meet the nutritional needs of sheep to meat production. Therefore, the objective of this experiment was to evaluate the agronomic characteristics of massaigrass in the dry season and the effect of protein supplements in the performance and productivity of sheep to meat production grazing. The protein supplements evaluated were: soybean meal, Leucena hay, Gliricidia hay and multiple mixture. The animals were managed in massaigrass pastures under rotational stocking and supplemented daily. Were used 24 sheep ½ Santa Inês x ½ SPRD (without defined breed), males uncastrated, mean age 90 days in a completely randomized design. Performance of sheep was evaluated for average daily gain of live weight gain per area and stocking rate (animals of 25 kg/ha). The pasture was evaluated for forage mass of pre and post-grazing, the percentages of participation of morphological constituents and their nutritional values and rates of herbage accumulation. The total herbage mass decreased throughout the dry season. Crude protein and in vitro digestibility of organic matter of the leaf were higher in the upper 15 cm of the canopy stratum. The average daily weight gain of the animals supplemented with legume hay was similar to that gained by animals supplemented with soybean meal in the four grazing cycles. The total live weight gain of animals supplemented with legume hay was higher than the animals supplemented only with multiple mixing the first two grazing cycles. Hays of Leucena and Gliricidia can be given for supplementation of sheep maintained on pasture

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Early childhood caries, especially in its severe form, which is characterized by an acute and aggressive nature, can have negative impacts on thequality of life of a child, due to effects such as difficulty in chewing, decreased appetite, weight loss, insomnia, changes in behavior and a decreased performance in school, among others. Moreover, the quality of life of the child`s family can also be affected, as the pain and discomfort caused by this type of caries result in loss of working days of parents, spending on dental treatments, changes in sleep patterns and stress. The aim of this study was to evaluate the impact of severe early childhood caries in the Oral Health-Related Quality of Life (OHRQoL) of public daycares`s preschool children through the Escala de Impacto da Saúde Bucal na Primeira Infância, a Brazilian version of the Early Childhood Oral Health Impact Scale (ECOHIS). A single calibrated examiner (kappa=1.0) evaluated, through the dmfs index, the oral health of 116 children aged between 3 and 5, which were included in one of three study groups: "caries-free", "not-severe early childhood caries" and "severe early childhood caries". The parents responded to ECOHIS, to assess their perception regarding the OHRQoL of their children, and a questionnaire on socioeconomic conditions. The OHRQoL was measured through the total scores and domains of ECOHIS. Descriptive analysis, Mann-Whitney test, Kruskal-Wallis test, chi-square test and Poisson multiple regression with robust variance were used. Among the children observed, 38.8% were caries-free, 27.6% showed not-severe early childhood caries and 33.6% showed severe early childhood caries. Regarding the total score of ECOHIS, severe early childhood caries had a greater negative impact on OHRQoL, compared to caries-free and not-severe early childhood caries groups (p <0.001). Regarding the child subscale, there was significant difference between the "severe early childhood caries" group and the other groups in all domains, except for theone of self-image / social interaction. In the family subscale domains, there was statistical significance between the severe early childhood caries and the caries-free groups in all domains (p <0.001), whereas between the "severe early childhood caries and not-severe early childhood caries groups there was a statistically significant difference only in the domain of parental anguish (p <0.001). Multivariate analysis showed that early childhood caries and the parent`s age were significantly associated to OHRQoL (p <0.05), independently of the other variables in the model. The presence of severe early childhood caries resulted in greater negative impact on OHRQoL (AdjPR= 6.016; 95%CI = 3.12 11.56; p<0.001), while older parents reported better OHRQoL (AdjPR = 0.603; 95%CI = 0.428 - 0.850; p = 0.004). The presence of severe early childhood caries had a negative impact on OHRQoL of preschool children and their families.