53 resultados para Variabilidade genómica


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The food chain theory predict that presence of omnivory prevent the trophic cascade and could be a strong stabilizing factor over resource and consumer community dynamics, and that the nutrient enrichment destabilize populations dynamics. Most of the freshwater tropical reservoirs are eutrophic, and strategies that seek improve the water quality through the control of phytoplankton biomass and nutrient input, become essential for the improvement and preservation of water quality. The aim of this study was test the zooplanktivory (when larvae) and omnivory (when young and adult) effects of Nile Tilapia over the structure and dynamics of plankton communities, in addition or absence of nutrients enrichment. For this, one field experiment was performed with a factorial design 2x3 resulting in six treatments: control, without fish and nutrient (C); with omnivorous fish (O); with zooplanktivorous fish (Z); without fish and with enrichment of nutrients (NP); with omnivorous fish and nutrients (ONP); and, with zooplanktivorous fish and nutrients (ZNP). The two planktivory types reduced the zooplankton biomass and increased the phytoplankton biomass, but the omnivory of filter-feeding fish attenuated the trophic cascade magnitude. The fertilization by nutrients increases the nutrient concentrations in water and the phytoplankton biomass, but the effect on zooplankton is dependent of the trophic structure. In a general way, the effects of the fish and nutrient addition were addictive, but significant interactions among those factors were observed in the answer of some zooplankton groups. The effects of omnivorous fish over the temporal variability of phytoplankton and zooplankton biomass were very variable, the increase or reduce in variability of the plankton depending of the level of nutrients and of the analyzed variable. With base in this study, we conclude that the planktivory type exercised by the fish and the concentrations of nutrients in the water affects the force of pelagic trophic cascades and probably the success of biomanipulation programs for the handling of water quality in lakes and tropical reservoirs

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Given the great diversity of fishes, the Order Tetraodontiformes stands to show genetic and morphological characteristics enough singular. The fishes of this order have a compact DNA which favors molecular studies, as well as comparisons with more basal species. Model of genome evolution, there are still many gaps in knowledge about their chromosomal patterns and how evolutionary rearrangements influence the marked variation in DNA content of this order. In view of this, we present cytogenetic analyzes of the species Acanthostracion quadricornis (Ostraciidae), A. polygonius (Ostraciidae) Melichthys niger (Balistidae) Cantherhines macrocerus (Monacanthidae) and C. pullus (Monacanthidae), Lagocephalus laevigatus, Colomesus psittacus and Canthigaster figueiredoi (Tetraodontidae), to contribute with cytogenetic data for this group. The analysis was performed by C-banding, Ag-RONs, coloring with base-specific fluorochromes DAPI-CMA3, restriction enzymes AluI, EcoRI, TaqI, PstI and HinfI and in situ hybridization with probes for ribosomal DNA 18S and 5S. The heterochromatic ultrastructure of A. quadricornis and A. polygonius revealed a outstanding heterochromatin content, which may indicate that the accumulation or loss of extensive heterochromatin content could be responsible for large variations in genomic content displayed in different Tetraodontiformes families. The species Cantherhines macrocerus, C. pullus (Monacanthidae) and Melichthys niger (Balistidae) shows a huge karyotypic similarity both numerically and structural. L. laevigatus showed similar cytogenetic features (2n = 44 and single RONs) to the species of the genus Takifugu, which reinforces the idea of their phylogenetic relationships. C. psittacus presented the highest diploid number described for the family (2n = 56) and large amount of HC, features that related with its sister family Diodontidae. Cytogenetic analysis in C. figueiredoi revealed heterochromatic polymorphisms, RONs multiple and Bs chromosomes. These events are rare in marine fishes, and are possibly associated with the strong restructuring and genomic reduction that this family has been suffered. These features, plus the morphological and molecular data suggests that these species share the same ancestral branch, with a possible monophyletic origin. In this study, new contributions to the knowledge of evolutionary patterns facing by Tetraodontiformes are provided and discussed under cytotaxonomyc, genomic and evolutionary perspectives.

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The Brazilian Northeast is the most vulnerable region to climatic variability risks. For the Brazilian semi-arid is expected a reduction in the overall rates of precipitation and an increase in the number of dry days. These changes predicted by the IPCC (2007) will intensify the rainfall and droughts period that could promote the dominance of cyanobacteria, thus affecting the water quality of reservoirs, that are most used for water supply, in the semi-arid. The aim of this study was to evaluate the effects of increasing temperature combined with nutrient enrichment on the functional structure of the phytoplankton community of a mesotrophic reservoir in the semi-arid, in the worst case scenario of climate change predicted by the IPCC (2007). Two experiments were performed, one in a rainy season and another in the dry season. In the water sampled, nutrients (nitrate and orthophosphate) were added in different concentrations. The microcosms were submitted to two different temperatures, five-year average of air temperature in the reservoir (control) and 4°C above the control temperature (warming). The results of this study showed that warming and nutrient enrichment benefited mainly the functional groups of cyanobacteria. During the rainy season it was verified the increasing biomass of small functional groups of unicellular and opportunists algae such as F (colonial green algae with mucilage) and X1 (nanoplanktonic algae of eutrophic lake systems). It was also observed an increasing in total biomass, in the richness and diversity of the community. In the dry season experiment there was a greater contribution in the relative biomass of filamentous algae, with a replacement of the group S1 (non-filamentous cyanobacteria with heterocytes) for H1 (filamentous cyanobacteria with heterocytes) in nutrient- enriched treatments. Moreover, there was also loss in total biomass, species richness and diversity of the community. The effects of temperature and nutrients manipulation on phytoplankton community of reservoir Ministro João Alves provoked changes in species richness, the diversity of the community and its functional composition, being the dry period which showed the highest susceptibility to the increase in the contribution of potentially toxic cyanobacteria with heterocytes

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Conselho Nacional de Desenvolvimento Científico e Tecnológico

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The complex human behavior related to exercise involves cognitive, physical and emotional processing. The recent theories about exercise s intensity regulation have highlighted the role played by psychophysics aspects in controlling exercise s intensity. In this regard, recent evidences have shown that there is variability in human capacity in perceiving interoceptives clues. Thus, subjects more sensitive show higher physiological arousal to physical and/or emotional stress, and sensations with higher intensity. In fact, studies have evidenced that interoceptive feedback modifies behavior in exercise with free load. However, exercise recommendations are based in a constant load standard. Therefore, we aimed to analyze the influence of interoceptive sensibility on psychophysics responses during dynamic exercise performed with constant load. Twenty-four adult males were allocated into two groups accordingly with their interoceptive sensibility: high sensibility (n=11) and low sensibility (13). They underwent to an incremental test (IT) and then randomly to two sections of moderate and severe exercise intensity for 20 minutes. Heart rate (HR), rating of perceived exertion (RPE), affective feelings (AF), alert state (AS), and percentage of associative thoughts were collect during exercise. A two-way ANOVA with repeated measures was used to assess differences between psychophysics responses. There were differences between group in RPE, AF, and AS in moderate intensity. There was no difference in any measure in severe intensity. We conclude that subjects with high interoceptive sensibility feel dynamic moderate exercise more intense than the subjecs with low interoceptive sensibility

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Introduction: The emergence of High Active Antiretroviral Therapy (HAART) increase the life expectancy of the persons living with HIV/AIDS (PLHIV), therefore the prolonged use cause metabolic implications and influences on body fat distribution and increase the cardiovascular diseases prevalence. Aims: Evaluate the effect of resistance training on heart rate variability, biochemical parameters and somatotype on PLHIV. Methods: Participated this study seven sedentary men, with age above 25 years old, living with HIV/AIDS, under HAART use. Were submitted a 16 week intervention with resistance training. Evaluated the heart rate variability, biochemical parameters and somatotype, before, after 8 weeks and 16 weeks, all in paired form. It was found the data normality by Shapiro-Wilk test and conducted the Anova one way combined with Tukey post hoc to samples in each evaluate moment, adopting significance level p<0,05. Also were calculated percentage change deltas. For somatotype was used the somatotype spatial distance (DES), obeying the significance value DES≥1. Results: Was found significance differences only in variable final heart rate delta 60s (p=0,01), however, is not showed changes on heart rate variability, biochemical parameters and somatotype components. Conclusion: 16 weeks of resistance training showed improvement on heart rate recovery after submaximal effort and, despite is not enough to produce significance differences on biochemical parameters and somatotype components, could be realize improvement on average value of fasting glucose and lipid profile, as well as reducing the endomorphic component

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In recent decades, the search for quality care has been widely discussed by the institutions and health professionals. In this context, it is the nurse coordinator of the process of providing nursing staff, reflecting the commitment to quality of care. In this process, it is the appearance of Infections Related to health care and its potential association with the workload in nursing as a valuable indicator of quality of care. Thus, this research contributes to studies to characterize the demand of nursing work to promote a safe healthcare practice. This study aimed to identify the association of nursing workload with the number of cases of Ventilator-Associated Pneumonia, urinary tract infection and central venous catheter infection in the intensive care unit. This is a quantitative research approach, descriptive, cross-sectional and prospective, held at Unimed Hospital in Natal-RN. The study population consisted of all patients treated in the Intensive Care Unit, Hospital for a period of 90 consecutive days in 2011. The convenience sample was compostapelos patients admitted to the ICU during the period of data collection, a total sample of 286 patients. To perform the data analysis software were used: Statistica 6.0, SPPS (Statistical Package for Social Sciences) version 17.0 (2004) and Excel 2007. In the descriptive analysis, we used Measures of Central Tendency and Measures of Dispersion or Variability and the use of nonparametric tests. Of the 286 patients, 88 were from the ICU and 198 ICU II II. Males predominated in the ICU I (51.1%) and female ICU II (57.6%) patients in the ICU I were aged 61-80 years (39.8%) followed by greater than 80 years (39.8%). In the ICU II, most of the patients were aged 61-80 years (38.9%) and then from 41 to 60 years (24.2%). In relation to the class of TISS inlet predominant class II in the two ICUs (59.1%), followed by Class III also in the two units (34.6%). Most patients (70.6%) out of the ICUs belonging to class II TISS. In the ICU I, the average number of forms of the TISS 28 was 6, has in ICU II this value drops to 3.2 forms. The overall mean was 19.9 TISS points in ICU patients I and ICU II.the 17 points in the average hours required to provide adequate nursing care to patients in the ICU I found that is 10 , 7 hours, and the ICU II 9.2 hours. It was found that the time provided by the nursing staff were higher in ICU II, with an average of 19 hours available for nurses in this sector. In the ICU I, which showed higher need of available hours, it was found that the mean value of 12.7 available hours. It was found that only 2.4% of patients had these units Ventilator-Associated Pneumonia, 1.0% were infected central venous catheter and 1.4% of patients had urinary tract infection. Infection associated with health care occurs, on average, on the tenth day of hospitalization. In the ICU II, this average value extends to the twelfth day with an excess of 2.7 hours of nursing care while in ICU I value decays to the ninth day of hospitalization with a deficiency of 12-hour assistance. It is concluded that patients generally showed a need for classification of semi-intensive care and has been assisted in their need to load. As for his association with the Related Infections Health will assist this analysis could not be performed due to the small number of notifications in this period. It is suggested further study how other factors related to infections me a longer period of analysis

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The attention with safety of the patients is important in the quality of the nursing and health care. In the pre-hospital care, such care is essential on site with the purpose of avoiding possible consequences to the individual, ensuring a fast and appropriate care, with improvement of the morbidity and reduction of the mortality. This medical attention is equally associated with the significant risks of adverse events and serious mistakes, which can be reduced with the awareness of the professionals, organization and quality management. It is a descriptive, transversal research, of quantitative approach, with the objective of identifying the risks for the safety of the patient during the mobile pre-hospital care under the view of the nurses, in a city of the Brazilian Northeast. The sample was formed by 23 nurses. The inclusion criteria: to have at least two years of experience and accept to participate on the research. The data collection was done in two steps, first photo collection, through the adapted method of photographic analysis, and the second with the application of questionnaire, divide in two parts: socio-professional data and digital photo punctuation instrument of the patient s safety. The majority of the nurses had an average working time in the mobile pre-hospital care of six years and six months, in the age group of 38 to 53 years old (69,56%) and with Lato sensu specialization (73,91%), being (29,41%) emergency and (29,41%) in intensive care. The (74%) have the Advance Cardiac Life Support (ACLS) and (100%) have the Pre-Hospital Trauma Life Support (PHTLS); (91, 30%) know the thematic safety of the patient. On the pictures it was observed a bigger variability of the categories (risks) where 44% of variance emerged on the first picture of the research. The pictures 4 and 9 with the average below 5 were classified as very insecure, while pictures 7 and 3 with an average above 7, very secure. On the results of risks observed for the patient s safety in the mobile pre-hospital care five categories emerged: organization and packaging of the equipment and materials, routines and specificities in the mobile pre-hospital care, risks on the management of medications, for traumas and infections. Starting from the analysis of these risks, it was proposed ten steps for the safety in the mobile pre-hospital care: 1- Identify the patient; 2- Safety related to prevention of infection; 3- Safety in the management of medications; 4- Safety and standardization of the packaging of equipment and materials; 5- Attention to the specificities of the mobile pre-hospital care; 6- Incentive and value the participation of the patient and family; 7- Promote the communication with the central of regulation; 8- Prevention of traumas and falls; 9- Protect the skin from additional injuries; 10- Understand the benefit of all the equipment in the ambulance. The multiple risks and their emerged combinations on the research indicate a variety of actions to be developed and stimulated, like the use of steps for the patient s safety in the mobile pre-hospital care which contributes with the aid and management of risks, reduction of mistakes, disabilities and death