869 resultados para Expectations hypothesis of term struscture of interest rates
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Background: With the emergence of strains resistant to conventional antibiotics, it is important to carry studies using alternative methods to control these microorganisms causing important infections, such as the use of products of plant origin that has demonstrated effective antimicrobial activity besides biocompatibility. Therefore, this study aimed to evaluate the antimicrobial activity of plant extracts of Equisetum arvense L., Glycyrrhiza glabra L., Punica granatum L. and Stryphnodendron barbatimam Mart. against Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus mutans, Candida albicans, Candida tropicalis, and Candida glabrata, and to analyze the cytotoxicity of these extracts in cultured murine macrophages (RAW 264.7).Methods: Antimicrobial activity of plant extracts was evaluated by microdilution method based on Clinical and Laboratory Standards Institute (CLSI), M7-A6 and M27-A2 standards. The cytotoxicity of concentrations that eliminated the microorganisms was evaluated by MTT colorimetric method and by quantification of proinflammatory cytokines (IL-1 and TNF-) using ELISA.Results: In determining the minimum microbicidal concentration, E. arvense L., P. granatum L., and S. barbatimam Mart. extracts at a concentration of 50 mg/mL and G. glabra L. extract at a concentration of 100 mg/mL, were effective against all microorganisms tested. Regarding cell viability, values were 48% for E. arvense L., 76% for P. granatum L, 86% for S. barbatimam Mart. and 79% for G. glabra L. at the same concentrations. About cytokine production after stimulation with the most effective concentrations of the extracts, there was a significant increase of IL-1 in macrophage cultures treated with S. barbatimam Mart. (3.98 pg/mL) and P. granatum L. (7.72 pg/mL) compared to control (2.20 pg/mL) and a significant decrease of TNF- was observed in cultures treated with G. glabra L. (4.92 pg/mL), S. barbatimam Mart. (0.85 pg/mL), E. arvense L. (0.83 pg/mL), and P. granatum L. (0.00 pg/mL) when compared to control (41.96 pg/mL).Conclusions: All plant extracts were effective against the microorganisms tested. The G. glabra L. extract exhibited least cytotoxicity and the E. arvense L. extract was the most cytotoxic. 2013 de Oliveira et al.; licensee BioMed Central Ltd.
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Includes bibliography
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The importance of science and technology (S&T) in Small Island Developing States (SIDS) is clearly articulated in Chapter XI, paragraphs 57, 58, 61 and 62 of the Mauritius Strategy for the Further Implementation of the Programme of Action for Sustainable Development of Small Island Developing States (MSI). At the regional level, the Heads of Government of the Caribbean Community (CARICOM) noted the challenge that CARICOM member States face in competing in this new international economic environment in which the impact of scientific and technological change has created a knowledge-based global economy. Given the importance of S&T to development of Caribbean SIDS, the Economic Commission for Latin America and the Caribbean (ECLAC) Subregional Headquarters for the Caribbean embarked on a study to determine the causes and consequences of low rates of specialisation in S&T with a view to making recommendations for development of strategies for addressing these challenges. Data on postgraduate (Master of Science, Master of Philosophy and Doctor of Philosophy) enrolment and graduation in agriculture, engineering and the sciences from the three campuses of the University of the West Indies (UWI) as well as from the University of Technology in Jamaica and the University of Trinidad and Tobago (UTT) were examined and analysed. Face-to-face interviews were also held with key personnel from these institutions and a questionnaire was also served to individuals in key institutions. Results of the study revealed that although the number of students enrolled in higher degree programmes has increased in absolute terms, they are decreasing in relative terms. However, enrolment in agriculture has indeed declined while enrolment rates in engineering, although increasing, were not significantly high. Market forces have proved to be a main reason for this trend while facilities for the conduct and supervision of cutting-edge research, the disconnect between science and industry and societal labelling of scientists as misfits are also contributing to the situation. This has resulted in a reduced desire by students at all levels of the school system and faculty to be involved in S&T; lack of innovation; a better staffed private, as compared with public, sector; and poor remuneration in science-based employment. There also appears to be a gender bias in enrolment with more males than females being enrolled in engineering while the opposite is apparent in agriculture and the sciences. Recommendations for remedying this situation range from increasing investment in S&T, creating linkages between science and industry as well as with the international community, raising awareness of the value of S&T at all levels of the education system to informing policy to stimulate the science innovation interface so as to promote intellectual property rights.
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Resolution 700(XXXVI) Mexico resolution on the establishment of the Forum of the Countries of Latin America and the Caribbean on Sustainable Development .-- Resolution of the Economic Commission for Latin America and the Caribbean on the establishment of the Forum of the Countries of Latin America and the Caribbean on Sustainable Development .-- Resolution 702(XXXVI) Statistical Conference of the Americas of the Economic Commission for Latin America and the Caribbean .-- Resolution 712(XXXVI) Regional integration of statistical and geospatial information.
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The efficiency of sources used for soil acidity correction depends on reactivity rate (RR) and neutralization power (NP), indicated by effective calcium carbonate (ECC). Few studies establish relative efficiency of reactivity (RER) for silicate particle-size fractions, therefore, the RER applied for lime are used. This study aimed to evaluate the reactivity of silicate materials affected by particle size throughout incubation periods in comparison to lime, and to calculate the RER for silicate particle-size fractions. Six correction sources were evaluated: three slags from distinct origins, dolomitic and calcitic lime separated into four particle-size fractions (2, 0.84, 0.30 and <0.30-mm sieves), and wollastonite, as an additional treatment. The treatments were applied to three soils with different texture classes. The dose of neutralizing material (calcium and magnesium oxides) was applied at equal quantities, and the only variation was the particle-size material. After a 90-day incubation period, the RER was calculated for each particle-size fraction, as well as the RR and ECC of each source. The neutralization of soil acidity of the same particle-size fraction for different sources showed distinct solubility and a distinct reaction between silicates and lime. The RER for slag were higher than the limits established by Brazilian legislation, indicating that the method used for limes should not be used for the slags studied here.
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Potassium fertilization is very important to alfalfa crop in terms of yield, quality and persistence of forage, especially on soils naturally poor K. Thus, to assess the effects of K fertilization in alfalfa production and nutritional status, was carried out an experiment in a greenhouse using samples of a Dystrophic Oxisol medium texture (LV) (0.6 mmol(c) dm(-3) K) and a Dystrophic Ultisol sandy/medium texture (PVA) (2.2 mmol(c) dm(-3) K). A completely randomized design in a factorial arrangement 6 x 2 (six K rates and two soils) was used, with four replications. The K rates used were: 0, 25, 50, 100, 150 and 200 mg kg(-1) K. Potassium fertilization increased K content in soil and shoots. Dry matter production was increased with the K addition. However, in the PVA, this occurred only in the second cut. In LV, potassium fertilization increased N concentration in alfalfa shoots in both cuts. Plants with K concentration around 10 g kg(-1) had typical symptoms of this nutrient deficiency. The K critical levels of K in soil and shoots were 1.8 mmolc dm(-3) and 16.7 g kg(-1), respectively.
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The use of legumes intercropped with forage in the Brazilian savannah (Cerrado) region is an alternative to reverse the process of pasture degradation. The natural phosphorus deficiency in this region and the high retention capacity of this nutrient in the soil are factors that directly affect the sustainability of the production system. The objective of this study was to evaluate the effect of a phosphate with medium solubility (Arad) compared to more soluble sources such as triple superphosphate and mono-ammonium phosphate, on the formation and maintenance of pastures of Andropogon gayanus with or without the introduction of Stylosantes guianensis in pasture already established in the Brazilian savannah. Two experiments were carried out under field conditions in an Oxisol using a randomized block design with split plots, plots with two sources of phosphorus (Arad and super-triple or MAP) and subplots with different levels of phosphorus. The study showed that andropogon grass, even though characterised as forage requiring low fertilization, responded to increased fertilization, especially with the use of more soluble sources of P at planting. From the second year on, with the introduction of Stylosantes guianensis, verified effects were seen on legumes in their efficiency of utilization of residual fertilization from the first year; however, this didn't affect legume dry matter production resulting from the P sources used for the andropogon grass. The mixed stands of andropogon grass and Stylosantes guianensis made it more advantageous to increase the P sources using phosphate fertilizer with lower solubility (Arad), when compared to MAP.
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The purpose of this study was to review the literature regarding the action of the cytokines interleukin 10 (IL-10) and tumor necrosis factor-alpha (TNF-) in pregnancy and to emphasize the factors that are of interest to clinical obstetrics. The literature highlights several actions of IL-10 and TNF- during pregnancy. The actions of these cytokines seem to be antagonistic and dependent on the balance between them, which is orchestrated by the specific immunosuppressive action of IL-10. TNF- has a characteristic inflammatory action, and it is an additional diabetogenic factor in pregnancy. The loss of the control of the production of these cytokines, with increase of TNF-, is related to the risk for developing obstetric complications, particularly recurrent fetal loss, gestational diabetes mellitus, hypertensive syndromes, and fetal growth restriction. However, study results are controversial and are not clearly defined. These issues are attributed to the heterogeneity of the studies, particularly regarding their sample sizes and sources, the evaluation methods, and the multiplicity of factors and conditions that influence cytokine production. These questions are fundamental and should be addressed in future investigations to obtain more consistent results that can be applied to obstetric practice.
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The tribe Pogonieae of Vanilloideae (Orchidaceae) consists of six genera, including Pogoniopsis, a mycoheterotrophic taxon with morphological characteristics distinct from the remaining of the tribe. A hypothesis about the phylogeny of the tribe was inferred, involving all currently recognized genera, based on isolated and combined sequence data of 5.8S, 18S and 26S (nrDNA) regions using parsimony and Bayesian analyses. Phylogenetic analyses show that inclusion of Pogoniopsis turns the tribe Pogonieae paraphyletic. All analyses reveal that Pogoniopsis is closely related to members of Epidendroideae. The pantropical Vanilla is monophyletic if Dictyophyllaria is assumed as synonym of Vanilla. Members of Pogonieae are pollinated by several groups of solitary and social bees, two pollination systems being recognized: reward-producing and deceptive. The molecular phylogeny suggests that ancestrals related to Pogonieae gave rise to two evolutionary lines: a tropical one with reward production of flowers, and a predominantly temperate regions invading line with deceptive flowers. Reward-producing flowers characterize the South and Central American clade (=Cleistes), while deceptive pollination is prominent in the clade that includes North American-Asiatic taxa plus the Amazonian genus Duckeella. (C) 2012 Elsevier GmbH. All rights reserved.
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Abstract Background Depressive symptoms and chronic disease have adverse effects on patients' health-related quality of life (H-RQOL). However, little is known about this effect on H-RQOL when only the two core depressive symptoms - loss of interest and depressed mood - are considered. The objective of this study is to investigate H-RQOL in the presence of loss of interest and depressed mood at a general medical outpatient unit. Methods We evaluated 553 patients at their first attendance at a general medical outpatient unit of a teaching hospital. H-RQOL was assessed with the Medical Outcomes Study 36-item Short-Form Health Survey (SF-36). Depressed mood and loss of interest were assessed by the Primary Care Evaluation of Mental Disorders (PRIME-MD)-Patient Questionnaire. A physician performed the diagnosis of chronic diseases by clinical judgment and classified them in 13 possible pre-defined categories. We used multiple linear regression to investigate associations between each domain of H-RQOL and our two core depression symptoms. The presence of chronic diseases and demographic variables were included in the models as covariates. Results Among the 553 patients, 70.5% were women with a mean age of 41.0 years (range 18-85, SD 15.4). Loss of interest was reported by 54.6%, and depressed mood by 59.7% of the patients. At least one chronic disease was diagnosed in 59.5% of patients; cardiovascular disease was the most prevalent, affecting 20.6% of our patients. Loss of interest and depressed mood was significantly associated with decreased scores in all domains of H-RQOL after adjustment for possible confounders. The presence of any chronic disease was associated with a decrease in the domain of vitality. The analysis of each individual chronic disease category revealed that no category was associated with a decrease in more than one domain of H-RQOL. Conclusion Loss of interest and depressed mood were associated with significant decreases in H-RQOL. We recommend these simple tests for screening in general practice.
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This thesis is based on the integration of traditional and innovative approaches aimed at improving the normal faults seimogenic identification and characterization, focusing mainly on slip-rate estimate as a measure of the fault activity. The LAquila Mw 6.3 April 6, 2009 earthquake causative fault, namely the Paganica - San Demetrio fault system (PSDFS), was used as a test site. We developed a multidisciplinary and scalebased strategy consisting of paleoseismological investigations, detailed geomorphological and geological field studies, as well as shallow geophysical imaging and an innovative application of physical properties measurements. We produced a detailed geomorphological and geological map of the PSDFS, defining its tectonic style, arrangement, kinematics, extent, geometry and internal complexities. The PSDFS is a 19 km-long tectonic structure, characterized by a complex structural setting and arranged in two main sectors: the Paganica sector to the NW, characterized by a narrow deformation zone, and the San Demetrio sector to SE, where the strain is accommodated by several tectonic structures, exhuming and dissecting a wide Quaternary basin, suggesting the occurrence of strain migration through time. The integration of all the fault displacement data and age constraints (radiocarbon dating, optically stimulated luminescence (OSL) and tephrochronology) helped in calculating an average Quaternary slip-rate representative for the PSDFS of 0.27 - 0.48 mm/yr. On the basis of its length (ca. 20 km) and slip per event (up to 0.8 m) we also estimated a max expected Magnitude of 6.3-6.8 for this fault. All these topics have a significant implication in terms of surface faulting hazard in the area and may contribute also to the understanding of the PSDFS seismic behavior and of the local seismic hazard.
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This dissertation is about collective action issues in common property resources. Its focus is the threshold hypothesis, which posits the existence of a threshold in group size that drives the process of institutional change. This hypothesis is tested using a six-century dataset concerning the management of the commons by hundreds of communities in the Italian Alps. The analysis seeks to determine the group size threshold and the institutional changes that occur when groups cross this threshold. There are five main findings. First, the number of individuals in villages remained stable for six centuries, despite the population in the region tripling in the same period. Second, the longitudinal analysis of face-to-face assemblies and community size led to the empirical identification of a threshold size that triggered the transition from informal to more formal regimes to manage common property resources. Third, when groups increased in size, gradual organizational changes took place: large groups split into independent subgroups or structured interactions into multiple layers while maintaining a single formal organization. Fourth, resource heterogeneity seemed to have had no significant impact on various institutional characteristics. Fifth, social heterogeneity showed statistically significant impacts, especially on institutional complexity, consensus, and the relative importance of governance rules versus resource management rules. Overall, the empirical evidence from this research supports the threshold hypothesis. These findings shed light on the rationale of institutional change in common property regimes, and clarify the mechanisms of collective action in traditional societies. Further research may generalize these conclusions to other domains of collective action and to present-day applications.