26 resultados para 1995_01191321 TM-33 4301502
em Universidade Federal do Rio Grande do Norte(UFRN)
Resumo:
Enfoca a educação continuada e a sua relação com a formação profissional do bibliotecário. Seu objetivo é refletir como integrar a capacitação contínua à formação desse profissional no contexto brasileiro. Pois, aspectos de ordem teórico-práticos apontam para a necessidade de maior incorporação de procedimentos metodológicos no fazer bibliotecário. Isto se dá em função de que as operações empíricas têm se tornado insuficientes para garantir a qualidade da informação gerada no âmbito de sistemas de informação. Assim, com base em ações-reflexões a partir desse contexto, identificou-se que necessário se faz adotar programas que possibilitem a capacitação desse profissional na formação-em-serviço, para melhor qualificar o processo de geração, transferência e uso da informação________________________________________________________________________________ABSTRACT Focus the continuous education and its relation with the professional formation of the librarian. Its objective is to reflect as to integrate the continuous qualification to the formation of this professional in the Brazilian context. Therefore, theoretician-practical aspects of order point with respect to the necessity of bigger incorporation of research procedures in making librarian. This if of the one in function of that the empirical operations if have become insufficient to guarantee the quality of the information generated in the scope of information systems. Thus, on the basis of action-reflections from this context, it was identified that necessary if it makes to adopt programs that make possible the qualification of this professional in the formation-in-service, better to characterize the generation process, transference and use of the information
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Several pharmacological properties have been attributed to isolated compounds from mushroom. Recently, have these compounds, especially the polysaccharides derived from mushrooms, modulate the immune system, and its antitumor, antiviral, antibiotic and antiinflammatory activities. This study assesses the possible pharmacological properties of the polysaccharides from Scleroderma nitidum mushroom. The centesimal composition of the tissue showed that this fungus is composed mainly of fibers (35.61%), ash (33.69%) and carbohydrates (25.31%). The chemical analysis of the polysaccharide fraction showed high levels of carbohydrates (94.71%) and low content of protein (5.29%). These polysaccharides are composed of glucose, galactose, mannose and fucose in the following molar ratios 0.156, 0.044, 0.025, 0.066 and the infrared analysis showed a possible polysaccharide-protein complex. The polysaccharides from Scleroderma nitidum showed antioxidant potential with concentration-dependent antioxidant activity compared to ascorbic acid. The analysis scavenging of superoxide radical and inhibition of lipid peroxidation showed that the polysaccharides from S. nitidum have an IC50 of 12.70 mg/ml and EC50 10.4 μg/ml, respectively. The antioxidant activity was confirmed by the presence of reducing potential of these polysaccharides. The effect of these polymers on the inflammatory process was tested using the carrageenan or histamine-induced paw edema model and the sodium thioglycolate or zymosan-induced model. The polysaccharides were effective in reducing edema (73% at 50 mg/kg) and cell infiltrate (37% at 10 mg/kg) in both inflammation models tested. Nitric oxide, a mediator in the inflammatory process, showed a reduction of around 26% at 10 mg/kg of body weight. Analysis of pro- and anti-inflammatory cytokines showed that in the groups treated with polysaccharides from S. nitidum there was an increase in cytokines such as IL-1ra, IL-10, and MIP-1β concomitant with the decrease in INF-γ (75%) and IL-2 (22%). We observed the influence of polysaccharides on the modulation of the expression of nuclear factor κB. Thus, polysaccharides from S. nitidum reduced the expression of NF-κB by up to 64%. The results obtained suggest that NF-κB modulation is one of the possible mechanisms that explain the anti-inflammatory effect of polysaccharides from the fungus S. nitidum.
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The Vitamin E consists of eight chemically homologous forms, designated alpha, beta, gamma and delta tocopherols and tocotrienols. Biologically, the alpha-tocopherol (α-TOH) is the most important. Commercially, are found two types of α-TOH a natural (RRR-alpha-tocopherol) and another synthetic (all-rac-alpha-tocopherol). Both forms are absorbed in the intestine, the liver is a preference in favor of forms 2R, due to transfer protein α-TOH. It has higher affinity to these stereoisomers. Newborns are considered high risk for vitamin E deficiency, mainly premature, these have breast milk as a food source for maintenance of serum α-TOH. Clinical signs such as thrombocytosis, hemolytic anemia, retrolental fibroplasia, intraventricular hemorrhage, bronchopulmonary dysplasia and spinocerebellar degeneration can be found in case of a low intake of α-TOH. Thus, maternal supplementation on postpartum with α-TOH can be an efficient way to increase levels of vitamin E in breast milk and thus the consequently increase the supply of micronutrient for the newborn. However, most studies with vitamin E supplementation have been conducted in animals and little is known about the effect of maternal supplementation in humans, as well as on its efficiency to increase levels of α-TOH in human milk, depending on the shape natural or synthetic. The study included 109 women, divided into three groups: control without supplementation (GC) (n=36), supplemented with natural capsule (GNAT) (n=40) and the synthetic capsule (GSINT) (n=33). Blood samples were collected for determination of maternal nutritional status, and colostrums at initial contact and after 24 hours post-supplementation. Analyses were performed by High Performance Liquid Chromatography. Values of α-TOH in serum below 499.6mg/dL were considered deficient. We used the Kruskal-Wallis test and Tukey test to confirm the increase of alpha-tocopherol in milk and efficiency of administered capsules. Daily consumption of α-TOH was based on daily intake of 500 mL of colostrum by the newborn and compared with the nutritional requirement for children from 0 to 6 months of age, 4 mg / day. The mothers had mean concentration of serum α-TOH in 1016 ± 52, 1236 ± 51 and 1083 ± 61 mg / dL, in CG, GNAT and GSINT respectively. There were no women with deficiiency. The GC did not change the concentrations of α-TOH in colostrum. While women supplemented with natural and synthetic forms increased concentrations of α-TOH colostrum in 57.6% and 39%, respectively. By comparing supplemented groups, it was observed a significant difference (p=0.04), the natural capsule more efficient than the synthetic, approximately 49.6%. Individually, 21.1% of the women provided below 4mg/day of α-TOH, after supplementation for this index declined4.1%. Thus, maternal supplementation postpartum raised the levels of alpha-tocopherol in colostrum, and increased efficiency was observed with the natural form
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The Iota, Kappa and Lambda commercial carrageenans are rarely pure and normally contain varying amounts of the other types of carrageenans. The exact amount of impurity depends on the seaweed source and extraction procedure. Then, different analysis methods have been applied for determination of the main constituents of carrageenans because these three carrageenans are extensively used in food, cosmetic and pharmaceutical industry. The electrophoresis of these compounds proved that the carrageenans are constituted by sulfated polysaccharides. These compounds were characterized by colorimetric methods and was observed that the Lambda carrageenan shown the greater value (33.38%) of sulfate. These polymers were examined by means of 13C NMR spectroscopy and infrared spectra. The polysaccharides consisted mainly of units alternating of sulfated galactoses and anhydrogalactoses. The aim of the study was also to test the inflammatory action of these different polysaccharides. A suitable model of inflammation is acute sterile inflammation of the rat hind limb induced by carrageenan. Paw edema was induced by injecting carrageenans (κ, ι and λ) in saline into the hind paw of a male Wistar rats (175–200 g). The pathway to acute inflammation by carrageenan (kappa, iota and lambda) were expressed as time-edema dependence and measured by paw edema volume. For this purpose, was used an apparatus (pakymeter), which makes it possible to measure the inflammation (swelling of the rat foot) with sufficient accuracy. The results showed that κ-carrageenan (1%) have an edema of 3.7 mm and the paw edema increase was time and dose dependent; the ι-carrageenan (0.2%) caused an edema of 4 mm and the λ-carrageenan (1%) caused an edema of 3.6 mm. Other model was used in this study based in the inflammation of pleura for comparatives studies. Injection of carrageenans into the pleural cavity of rat induced an acute inflammatory response characterized by fluid accumulation in the pleural cavity, a large number of neutrophils and raised NO production. The levels of NO were measured by Griess reactive. The ι-carrageenan caused the greater inflammation, because it has high concentration of nitrite/nitrate (63.478 nmoles/rat), exudato volume (1.52 ml) and PMNs (4902 x 103 cells). Quantitative evaluation of inflammations of rats is a useful and important parameter for the evaluation of the efficacy of anti-inflammatory drugs
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
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Recent studies are investigating a new class of inorganic materials which arise as a promising option for high performance applications in the field of photoluminescence. Highlight for rare earth (TR +3 ) doped, which have a high luminous efficiency, long decay time and being able to emit radiation in the visible range, specific to each element. In this study, we synthesized ZrO2: Tb +3 , Eu +3 , Tm +3 nanoparticles complex polymerization method (CPM). We investigated the influences caused by the heat treatment temperature and the content of dopants in zirconia photoluminescent behavior. The particles were calcined at temperature of 400, 500 and 600 ° C for two hours and ranged in concentration of dopants 1, 2, 4 and 8 mol% TR +3 . The samples were characterized by thermal analysis, X-ray diffraction, photoluminescence of measurements and uv-visible of spectroscopies. The results of X-ray diffraction confirmed the formation of the tetragonal and cubic phases in accordance with the content of dopants. The photoluminescence spectra show emission in the region corresponding simultaneous to blue (450 nm), green (550 nm) and red (615 nm). According to the results, ZrO2 particles co-doped with rare earth ions is a promising material white emission with a potential application in the field of photoluminescence
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The program PROBIODIESEL from the Ministry of Science and Technology has substantially increased glycerine, obtained as a sub-product of biodiesel production process, making it necessary to seek alternatives for the use of this co-product. On the other hand, herbicides although play a role of fundamental importance in the agricultural production system in force, have been under growing concern among the various segments of society because of their potential environmental risk. In this work, we used glycerin in microemulsion systems for application of herbicides, to improve efficiency and lower environmental pollution caused by the loss of those products to the environment. To obtain the systems of microemulsinados were used Unitol L90 NP and Renex 40 as surfactants, butanol as co-surfactant, coconut oil as oil phase and aqueous phase as we used solutions of glycerin + water. Through the determination of phase diagrams, the microemulsion region was found in the system E (L90 Unitol, coconut oil and glycerin + water 1:1). Three points were chosen to the aqueous phase rich in characterization and application in the solubilization of glyphosate and atrazine. Three experiments were performed in Horta, Department of Plant Sciences, Plant Science Sector, UFERSA, Mossoró-RN. The first experiment was conducted in randomized complete blocks with 20 treatments and four replications. The treatments consisted of five doses of the herbicide glyphosate (0.0, 0.45, 0.9, 1.35 and 1.8 L ha-1) diluted with four sauces: C1, C2, C3 (microemulsions) and C4 (water). The phytotoxicity of Brachiaria brizantha was measured at 7, 14, 28 and 60 DAA (days after application). At 60 DAA, we evaluated the biomass of plants. The second experiment was developed in randomized complete blocks with 20 treatments and four repetitions. The treatments consisted of five doses of the herbicide atrazine (0.0, 0.4, 0.8, 1.6 and 2.4 L ha-1) diluted with four sauces: C1, C2, C3 (microemulsions) and C4 (water). The phytotoxicity on Zea mays and Talinum paniculatum was evaluated at 2, 7, 20 DAA. The experiment III was developed in randomized complete blocks with 16 treatments and three repetitions. The treatments consisted of 16 combinations among the constituents of the microemulsion: Unitol L90 surfactant (0.0, 1.66, 5.0, 15 %) and glycerin (0.0, 4.44, 13.33 and 40.0 %). The phytotoxicity on Zea mays was evaluated at 1, 7 and 14 DAA. At 14 DAA, we evaluated the biomass of plants. The control plants using the microemulsions was lower than in the water due to the poisoning caused by the initial microemulsions in the leaves of the plants, a fact that hinders the absorption and translocation of the herbicide. There was no toxicity in Zea mays plants caused by the herbicide, however, were highly intoxicated by microemulsions. T. paniculatum was better controlled in spraying with the microemulsions, regardless of the dose of the herbicide. The glycerine did not cause plant damage. Higher poisoning the plants are caused by tensoactive Unitol L90 and higher rates occur with the use of higher concentrations of surfactant and glycerin, or microemulsion. The microemulsions used hampered the action of glyphosate in controlling B. brizantha and caused severe poisoning in corn, and these poisonings attributed mainly to the action of surfactant
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The increasing use of fossil fuels in line with cities demographic explosion carries out to huge environmental impact in society. For mitigate these social impacts, regulatory requirements have positively influenced the environmental consciousness of society, as well as, the strategic behavior of businesses. Along with this environmental awareness, the regulatory organs have conquered and formulated new laws to control potentially polluting activities, mostly in the gas stations sector. Seeking for increasing market competitiveness, this sector needs to quickly respond to internal and external pressures, adapting to the new standards required in a strategic way to get the Green Badge . Gas stations have incorporated new strategies to attract and retain new customers whom present increasingly social demand. In the social dimension, these projects help the local economy by generating jobs and income distribution. In this survey, the present research aims to align the social, economic and environmental dimensions to set the sustainable performance indicators at Gas Stations sector in the city of Natal/RN. The Sustainable Balanced Scorecard (SBSC) framework was create with a set of indicators for mapping the production process of gas stations. This mapping aimed at identifying operational inefficiencies through multidimensional indicators. To carry out this research, was developed a system for evaluating the sustainability performance with application of Data Envelopment Analysis (DEA) through a quantitative method approach to detect system s efficiency level. In order to understand the systemic complexity, sub organizational processes were analyzed by the technique Network Data Envelopment Analysis (NDEA) figuring their micro activities to identify and diagnose the real causes of overall inefficiency. The sample size comprised 33 Gas stations and the conceptual model included 15 indicators distributed in the three dimensions of sustainability: social, environmental and economic. These three dimensions were measured by means of classical models DEA-CCR input oriented. To unify performance score of individual dimensions, was designed a unique grouping index based upon two means: arithmetic and weighted. After this, another analysis was performed to measure the four perspectives of SBSC: learning and growth, internal processes, customers, and financial, unifying, by averaging the performance scores. NDEA results showed that no company was assessed with excellence in sustainability performance. Some NDEA higher efficiency Gas Stations proved to be inefficient under certain perspectives of SBSC. In the sequence, a comparative sustainable performance and assessment analyzes among the gas station was done, enabling entrepreneurs evaluate their performance in the market competitors. Diagnoses were also obtained to support the decision making of entrepreneurs in improving the management of organizational resources and promote guidelines the regulators. Finally, the average index of sustainable performance was 69.42%, representing the efforts of the environmental suitability of the Gas station. This results point out a significant awareness of this segment, but it still needs further action to enhance sustainability in the long term
Resumo:
The dyslipidemia and excess weight in adolescents, when combined, suggest a progression of risk factors for cardiovascular disease (CVD). Besides these, the dietary habits and lifestyle have also been considered unsuitable impacting the development of chronic diseases. The study objectives were: (1) estimate the prevalence of lipid profile and correlate with body mass index (BMI), waist circumference (WC) and waist / height ratio (WHR) in adolescents, considering the maturation sexual, (2) know the sources of variance in the diet and the number of days needed to estimate the usual diet of adolescents and (3) describe the dietary patterns and lifestyle of adolescents, family history of CVD and age correlates them with the patterns of risk for CVD, adjusted for sexual maturation. A cross-sectional study was performed with 432 adolescents, aged 10-19 years from public schools of the Natal city, Brazil. The dyslipidemias were evaluated considering the lipid profile, the index of I Castelli (TC / HDL) and II (LDL / HDL) and non-HDL cholesterol. Anthropometric indicators were BMI, WC and WHR. The intake of energy, nutrients including fiber, fatty acids and cholesterol was estimated from two 24-hour recalls (24HR). The variables of lipid profile, anthropometric and clinical data were used in the models of Pearson correlation and linear regression, considering the sexual maturation. The variance ratio of the diet was calculated from the component-person variance, determined by analysis of variance (ANOVA). The definition of the number of days to estimate the usual intake of each nutrient was obtained by taking the hypothetical correlation (r) ≥ 0.9, between nutrient intake and the true observed. We used the principal component analysis as a method of extracting factors that 129 accounted for the dependent variables and known cardiovascular risk obtained from the lipid profile, the index for Castelli I and II, non-HDL cholesterol, BMI, and WC the WHR. Dietary patterns and lifestyle were obtained from the independent variables, based on nutrients consumed and physical activity weekly. In the study of principal component analysis (PCA) was investigated associations between the patterns of cardiovascular risk factors in dietary patterns and lifestyle, age and positive family history of CVD, through bivariate and multiple logistic regression adjusted for sexual maturation. The low HDL-C dyslipidemia was most prevalent (50.5%) for adolescents. Significant correlations were observed between hypercholesterolemia and positive family history of CVD (r = 0.19, p <0.01) and hypertriglyceridemia with BMI (r = 0.30, p <0.01), with the CC (r = 0.32, p <0.01) and WHR (r = 0.33, p <0.01). The linear model constructed with sexual maturation, age and BMI explained about 1 to 10.4% of the variation in the lipid profile. The sources of variance between individuals were greater for all nutrients in both sexes. The reasons for variances were 1 for all nutrients were higher in females. The results suggest that to assess the diet of adolescents with greater precision, 2 days would be enough to R24h consumption of energy, carbohydrates, fiber, saturated and monounsaturated fatty acids. In contrast, 3 days would be recommended for protein, lipid, polyunsaturated fatty acids and cholesterol. Two cardiovascular risk factors as have been extracted in the ACP, referring to the dependent variables: the standard lipid profile (HDL-C and non-HDL cholesterol) and "standard anthropometric index (BMI, WC, WHR) with a power explaining 75% of the variance of the original data. The factors are representative of two independent variables led to dietary patterns, "pattern 130 western diet" and "pattern protein diet", and one on the lifestyle, "pattern energy balance". Together, these patterns provide an explanation power of 67%. Made adjustment for sexual maturation in males remained significant variables: the associations between puberty and be pattern anthropometric indicator (OR = 3.32, CI 1.34 to 8.17%), and between family history of CVD and the pattern lipid profile (OR = 2.62, CI 1.20 to 5.72%). In females adolescents, associations were identified between age after the first stage of puberty with anthropometric pattern (OR = 3.59, CI 1.58 to 8.17%) and lipid profile (OR = 0.33, CI 0.15 to 0.75%). Conclusions: The low HDL-C was the most prevalent dyslipidemia independent of sex and nutritional status of adolescents. Hypercholesterolemia was influenced by family history of CVD and sexual maturation, in turn, hypertriglyceridemia was closely associated with anthropometric indicators. The variance between the diets was greater for all nutrients. This fact reflected in a variance ratio less than 1 and consequently in a lower number of days requerid to estimate the usual diet of adolescents considering gender. The two dietary patterns were extracted and the pattern considered unhealthy lifestyle as healthy. The associations were found between the patterns of CVD risk with age and family history of CVD in the studied adolescents
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Extensive studies using molecular markers on butterflies have shown how a highly fragmented landscape may result in the reduction of gene flow among patches of habitat and, consequently, increase genetic differentiation among populations. However, little is known about Heliconius geographical structure and the effects of fragmentation on the connectivity of populations. Furthermore, findings on the effects of the population structure on the dynamics of mimicry evolution in Heliconius butterflies need to be tested in H. erato and H. melpomene specimens found in other locations other than Central and northern South Americas. For the present study, we had two motivations: (1) compare the population structure of H. erato and H. melpomene given the highly fragmented Brazil s Atlantic Forest habitat; and (2) studying population structure of co-mimics could give us insights into the dynamics of mimicry evolution. For this, we analysed the spatial structure and connectivity of eight populations of Heliconius butterflies, in a total of 137 H. erato specimens and 145 H. melpomene specimens, using nine microsatellites loci, 1144 AFLPs markers and 282 mitochondrial DNA sequences. In general, both species exhibited evidence of population subdivision but no isolation by distance indicating some extent of genetic differentiation among populations. Contrary to Kronforst & Gilbert s (2008) Costa Rican Heliconius, H. melpomene exhibited more genetic differentiation than H. erato based on nuclear markers. However, for mitochondrial DNA, H. erato populations showed more genetic differentiation than H. melpomene. Our results corroborate to other studies on Heliconius butterflies concerning the pronounced population subdivision and local genetic drift found in this genus. Nevertheless, the pattern of this differentiation varies significantly from the pattern found in studies conducted in Central America, where H. erato is generally more differentiated and structured than H. melpomene, based on nuclear markers. This different pattern may reflect different evolutionary histories of Heliconius species in Northeastern Brazil s Atlantic Forest
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Os cavalos-marinhos têm cativado a imaginação e a curiosidade dos seres humanos por centenas de anos. No entanto, nos dias de hoje, esses animais correm um sério risco de extinção por fatores como a pesca desordenada para suprir os mercados de peixes ornamentais e da medicina tradicional chinesa e principalmente, a destruição do seu habitat. Nesse contexto, é crescente o número de estudos sobre a ecologia, a biologia (reprodutiva, especialmente) e o cultivo de várias espécies do gênero Hippocampus, inclusive para fins conservacionistas e de recomposição de estoques. Duas espécies de cavalos-marinhos são encontradas no Brasil: Hippocampus reidi Ginsburg 1933 e Hippocampus erectus Perry. No entanto, as informações sobre essas espécies estão basicamente restritas ao seu grau de ocorrência ou a sua área de ocupação. No presente estudo, foi avaliado o desempenho reprodutivo de Hippocampus reidi do estuário do rio Potengi (05° 47' 42'' S; 35° 12' 34'' W), em Natal, Rio Grande do Norte. Para tanto, cavalos-marinhos grávidos (n = 38) foram coletados no referido estuário nos meses de setembro, outubro e novembro de 2008 e julho, agosto, setembro e outubro de 2009 e mantidos em laboratório até que liberassem os filhotes. O comprimento padrão (CPA), altura (ATA), volume da bolsa (VB) e peso úmido (PuA) dos adultos, bem como o comprimento padrão (CPF), altura (ATF), peso úmido (PuF) e peso seco (PsF) dos filhotes foram determinados. Os resultados obtidos mostraram que houve correlações significativas entre o CPA e a ATA (r²=0,171), CPA e PuA (r²=0,624), CPA e VB (r²=0,256), ATA e PuA (r²=0,788), PuA e VB (r²=0,211), CPF e ATF (r²=0,903) e CPF e PsF (r²=0,163). A análise de correspondência (AC) que associou as classes do comprimento padrão dos adultos (CPA) e o volume da bolsa de H. reidi ao número de filhotes mostrou que animais entre 19 cm e 21 cm e com volume de bolsa entre 3 mL e 4 mL foram os que liberaram o maior número de filhotes. Os resultados do presente estudo também indicam que o tamanho mínimo de captura recomendado pela CITES (10 cm de altura) para H. reidi deve ser revisto, uma vez que não foram encontrados animais menores que 13,5 cm que estivessem grávidos. Finalmente, o número médio de filhotes por desova obtido no presente estudo (n = 775 ± 398 filhotes) realçou o potencial reprodutivo de H. reidi e a necessidade de estudos adicionais com esta espécie
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High levels of local, regional, and global extinctions has progressively simplified communities in terms of both species and ecosystem functioning. Theoretical models demonstrated that the degree of functional redundancy determines the rates of functional group loss in response to species extinctions. Here, we improve the theoretical predictions by incorporating in the model interactions between species and between functional groups. In this study, we tested the effect of different scenarios of interspecific interactions and effects between functional groups on the resistance to loss of community functional groups. Virtual communities have been built with different distribution patterns of species in functional groups, both with high and low evenness. A matrix A was created to represent the net effect of interspecific interactions among all species, representing nesting patterns, modularity, sensitive species, and dominant species. Moreover, a second matrix B was created to represent the interactions between functional groups, also exhibiting different patterns. The extinction probability of each species was calculated based on community species richness and by the intensity of the interspecific interactions that act upon it and group to which it belongs. In the model, successive extinctions decrease the community species richness, the degree of functional redundancy and, consequently, the number of functional groups that remain in the system. For each scenario of functional redundancy, A, and B, we ran 1000 simulations to generate an average functional extinction curve. Different model assumptions were able to generate remarkable variation on functional extinction curves. More extreme variations occurred when the matrix A and B caused a higher heterogeneity in the species extinction probability. Scenarios with sensitive species, positive or negative, showed a greater variation than the scenarios with dominant species. Nested interactions showed greater variation than scenarios where the interactions were in modules. Communities with maximal functional evenness can only be destabilized by the interactions between species and functional groups. In contrast, communities with low functional evenness can have its resistance either increased or decreased by the interactions. The concentration of positive interactions in low redundancy groups or negative interactions in high redundancy groups was able to decrease the functional extinction rates. In contrast, the concentration of negative interactions in low redundancy groups or positive interactions in high redundancy groups was able to increase the functional extinction rates. This model shows results that are relevant for species priorization in ecosystem conservation and restoration
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Octopus insularis, target species in this study, is the dominant benthic octopus of the North and Northeast Brazil. Studies on behavior and ecology of the species have been conducted primarily on oceanic islands, with little information on the continental populations. In this study, two regions of the coast of RN, Rio do Fogo and Pirangi, were chosen for the characterization of the niche by O. insularis populations. The dietary niche, habitat and distribution of O. insularis of oceanic islands and the mainland, were compared. In addition, individual characteristics of feeding behavior in a population at Atol das Rocas was studied, taking into account the size of individuals, the proximity of the dens and characteristics of their "personality". The diet of the Rio do Fogo population was composed mainly of bivalve molluscs (82%), unlike Pirangi population that has a diet consisting mainly of crustaceans Decapoda (68%), similar to that described for the populations of the islands. Consequently, the feeding niches of the island populations were more similar, with greater overlap, but the niche breadth of the continent was larger. The habitats of occurrence on the coast includes reefs, rocks, gravel and an environment called Restinga, a plateau composed of biogenic gravel, sand, sponges and algae, showed a high density of animals. Similarly to that found in the islands, O. insularis in the continent, had a clumped distribution, and a bathymetric segregation between small and large individuals. The differences in diet composition among populations were explained by differences in habitat and coverage of the substrate, which may be directly influencing the diversity and prey availability in these environments. The individual analyzes of the population at Atol das Rocas, showed no relationship between the degree of individual specialization and the different personalities, or the distance between dens. The results suggest that the foraging strategy with greater availability of prey in the environment has an influence on diet octopuses over preferences or personalities
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Studies on the effects of changes in biodiversity and ecosystem functioning have been a central theme in ecology over the past two decades. Several studies have showed that the diversity of plant debris differently affects the decomposition process in aquatic and terrestrial environments, but we know very about the effects of detritus diversity on decomposition under fluctuating environmental conditions. We tested whether and how the environmental contexts, as well as the dynamic of their alternation, influence the effects of detritus diversity on the decomposition process. We performed a field experiment where we manipulate the litter diversity of 8 species of terrestrial plants decomposing (litterbags) in single and in mixture containing the eight species together in three different environmental contexts: the terrestrial environment (T), aquatic (A) and interface (I) - experimental treatment that simulates variation in flooding regime. We measured the rate of decomposition through the loss of mass of the community and each individual detritus in monocultures and mixtures. Species richness and environmental variability had no effects on the magnitude and stability of the decomposition process. However, there were significant diversity effects on the decomposition of an individual alien species, F. benjamina. Environmental context had significant effects on the magnitude and variability of decomposition. Detritus decomposition was faster and more variable on aquatic, interface and terrestrial conditions, respectively. Our results demonstrate that the diversity of plant detritus has minor effects to the decomposition across disparate environmental conditions and suggest that it is necessary to consider the potential of other abiotic factors in affect the magnitude and variability of the decomposition processes
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior