119 resultados para econd language acquisition, identity, tensi on, investment, motivation, community of practice
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A critical analysis of the type collections of 39 species names of Paspalum L. (Poaceae: Paniceae) from Brazil described by Swallen is presented along with comments based on more recent gatherings of the species. Eighteen new synonyms are proposed.
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The effects of food concentration and temperature on embryonic and postem-bryonic duration of three tropical species, Daphnia gessneri(1.5mm), Diaphanosoma sarsi(1.2mm) and Moina reticulata(0.8mm), were investigated as part of life cycle studies which included growth, body size and reproduction. These are the very first experimental studies undertaken on these species. The long-term growth experiments were performed under controlled laboratory conditions at all combinations of temperature (22"C, 27"C and 32"C) and constant food concentration (0.03, 0.05, 0.10, 0.25, 0.50 and 1.00 mgC/L) of the unicellular green alga Scenedesmus acutus.Animals were examined twice daily throughout their life cycle from the neonate to third adult instar. In all three species, temperature exerted the most powerful influence on embryonic duration but there was also a smaller food effect. In D. gessneri,postembry-onic durations remained more or less the same at food levels 0.25 mgC/L but were influenced by temperature. At food concentrations of 0.1 mgC/L or lower, postembryonic durations became increasingly prolonged, particularly at high temperatures. This threshold concentration is affected by temperature: in D. gessneri,it was 0.1 mgC/L at 22oC and 27oC but higher at 32oC (between 0.25 and 0.50 mgC/L). At the same temperature of 27oC, the food threshold level varied between species: it was higher (0.25 mgC/L) for D. sarsiand lower (0.05 mgC/L) for M. reticulatacompared with D. gessneri(0.1 mgC/L). In both embryonic and postembryonic durations there is a body size effect as the absolute durations were longest in the largest species and shortest in the smallest species In all three species, prolongation of postembryonic duration at combinations of high temperature and lowered food levels was accompanied by increased number of juvenile instars.
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Fish transport is one of the most stressful procedures in aquaculture facilities. The present work evaluated the stress response of matrinxã to transportation procedures, and the use of clove oil as an alternative to reduce the stress response to transport in matrinxã (Brycon cephalus). Clove oil solutions were tested in concentrations of 0, 1, 5 and 10 mg/L during matrinxã transportation in plastic bags, supplied with water and oxygen as the usual field procedures in Brazil. Clove oil reduced some of the physiological stress responses (plasma cortisol, glucose and ions) that we measured. The high energetic cost to matrinxã cope with the transport stress was clear by the decrease of liver glycogen after transport. Our results suggest that clove oil (5 mg/l) can mitigate the stress response in matrinxã subjected to transport.
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This article aims to describe important points in the history of panic disorder concept, as well as to highlight the importance of its diagnosis for clinical and research developments. Panic disorder has been described in several literary reports and folklore. One of the oldest examples lies in Greek mythology - the god Pan, responsible for the term panic. The first half of the 19th century witnessed the culmination of medical approach. During the second half of the 19th century came the psychological approach of anxiety. The 20th century associated panic disorder to hereditary, organic and psychological factors, dividing anxiety into simple and phobic anxious states. Therapeutic development was also observed in psychopharmacological and psychotherapeutic fields. Official classifications began to include panic disorder as a category since the third edition of the American Classification Manual (1980). Some biological theories dealing with etiology were widely discussed during the last decades of the 20th century. They were based on laboratory studies of physiological, cognitive and biochemical tests, as the false suffocation alarm theory and the fear network. Such theories were important in creating new diagnostic paradigms to modern psychiatry. That suggests the need to consider a wide range of historical variables to understand how particular features for panic disorder diagnosis have been developed and how treatment has emerged.
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OBJECTIVE: A double-blind, placebo-controlled multicenter study involving 34 centers from different Brazilian regions was performed to evaluate the antihypertensive efficacy and tolerability of trandolapril, an angiotensin I converting enzyme inhibitor, in the treatment of mild-to-moderate systemic arterial hypertension. METHODS: Of 262 patients enrolled in this study, 127 were treated with trandolapril 2 mg/day for 8 consecutive weeks, and the remaining 135 patients received placebo for the same period of time. Reduction in blood pressure (BP) and the occurrence of adverse events during this period were evaluated in both groups. RESULTS: Significant reductions in both systolic and diastolic pressures were observed in patients treated with trandolapril when compared with those on placebo. Antihypertensive efficacy was achieved in 57.5% of the patients on trandolapril and in 42% of these normal values of BP were obtained. The efficacy of trandolapril was similar in all centers, regardless of the area of the country. In a subset of 30 patients who underwent ABPM, responders showed a significant hypotensive effect to trandolapril throughout the 24 hour day. The adverse event profile was similar in both trandolapril and placebo groups. CONCLUSION: Our results demonstrate, for the first time in a large group of hypertensive patients from different regions in Brazil, good efficacy and tolerability of trandolapril during treatment of mild-to-moderate essential systemic hypertension.
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OBJECTIVE: To assess the effect of a new feed soy product fermented by Enterococcus faecium and Lactobacillus jugurti on the serum lipid levels of rabbits with induced hypercholesterolemia. METHODS: Thirty-two rabbits were divided into 4 groups as follows: 1) control (C); 2) hypercholesterolemic (H); 3) hypercholesterolemic + fermented product (HPF); and 4) control + fermented product (CPF). The H and HPF groups were fed with a diet with 0.15% (p/p) cholesterol in the first 15 days. C and CPF groups received regular food preparation. The HPF and CPF groups received 10 mL daily of the fermented 30 days. Blood samples were drawn at the beginning of the study and at the 15th and 30th days. Concentrations of total cholesterol, HDL-cholesterol, and triglycerides were analyzed. RESULTS: After 15 days, the HPF group showed a total cholesterol concentration lower (18.4%) than that of the H group (p=0.05), but this difference disappeared after 30 days. No change was observed in total cholesterol levels of C and CPF groups. After 15 days, the HDL-cholesterol was higher (17.8%) in the HPF group, but the triglyceride levels remained unchanged in all groups during the same period of time. CONCLUSION: The soy fermented product caused an 18.4% reduction in total cholesterol and a 17.8% increase in the HDL-fraction. It may, therefore, be a possible coadjutor in the treatment of hypercholesterolemia.
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OBJECTIVE: To study the effect of propafenone on the contractile function of latissimus dorsi muscle isolated from rats in an organ chamber. METHODS: We studied 20 latissimus dorsi muscles of Wistar rats and divided them into 2 groups: group I (n=10), or control group - we studied the feasibility of muscle contractility; group II (n=10), in which the contralateral muscles were grouped - we analyzed the effect of propafenone on muscle contractility. After building a muscle ring, 8 periods of sequential 2-minute baths were performed, with intervals of preprogrammed electrical stimulation using a pacemaker of 50 stimuli/min. In group II, propafenone, at the concentration of 9.8 µg/mL, was added to the bath in period 2 and withdrawn in period 4. RESULTS: In group I, no significant depression in muscle contraction occurred up to period 5 (p>0.05). In group II, a significant depression occurred in all periods, except between the last 2 periods (p<0.05). Comparing groups I and II only in period 1, which was a standard period for both groups, we found no significant difference (p>0.05). CONCLUSION: Propafenone had a depressing effect on the contractile function of latissimus dorsi muscle isolated from rats and studied in an organ chamber.
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OBJECTIVE: To assess the acute effects of high glucose concentrations on vascular reactivity in the isolated non diabetic rabbit kidney. METHODS: Rabbits were anaesthetized for isolation of the kidneys. Renal arteries and veins were cannulated for perfusion with Krebs-Henselleit solution and measurement of perfusion pressure. After 3 hours of perfusion with glucose 5,5 mM (control ) and 15 mM, the circulation was submitted to sub maximal precontraction (80% of maximal response) trough continuous infusion of noradrenaline 10 mM. Vascular reactivity was then assessed trough dose-responses curves with endothelium-dependent (acetylcholine) and independent (sodium nitroprusside) vasodilators. The influence of hyperosmolarity was analyzed with perfusion with mannitol 15mM. RESULTS: A significant reduction in the endothelium-dependent vasodilation in glucose 15mM group was observed compared to that in control, but there was no difference in endothelium-independent vasodilation. After perfusion with mannitol 15 mM, a less expressive reduction in endothelium-dependent vasodilation was observed, only reaching significance in regard to the greatest dose of acetylcholine. CONCLUSION: High levels of glucose similar to those found in diabetic patients in the postprandial period can cause significant acute changes in renal vascular reactivity rabbits. In diabetic patients these effects may also occur and contribute to diabetes vascular disease.
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Introductions: In the care of hypertension, it is important that health professionals possess available tools that allow evaluating the impairment of the health-related quality of life, according to the severity of hypertension and the risk for cardiovascular events. Among the instruments developed for the assessment of health-related quality of life, there is the Mini-Cuestionario of Calidad de Vida en la Hipertensión Arterial (MINICHAL) recently adapted to the Brazilian culture. Objective: To estimate the validity of known groups of the Brazilian version of the MINICHAL regarding the classification of risk for cardiovascular events, symptoms, severity of dyspnea and target-organ damage. Methods: Data of 200 hypertensive outpatients concerning sociodemographic and clinical information and health-related quality of life were gathered by consulting the medical charts and the application of the Brazilian version of MINICHAL. The Mann-Whitney test was used to compare health-related quality of life in relation to symptoms and target-organ damage. The Kruskal-Wallis test and ANOVA with ranks transformation were used to compare health-related quality of life in relation to the classification of risk for cardiovascular events and intensity of dyspnea, respectively. Results: The MINICHAL was able to discriminate health-related quality of life in relation to symptoms and kidney damage, but did not discriminate health-related quality of life in relation to the classification of risk for cardiovascular events. Conclusion: The Brazilian version of the MINICHAL is a questionnaire capable of discriminating differences on the health‑related quality of life regarding dyspnea, chest pain, palpitation, lipothymy, cephalea and renal damage.
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AbstractBackground:Hypertension is a public health problem and increases the incidence of cardiovascular diseases.Objective:To evaluate the effects of a resistance exercise session on the contractile and relaxing mechanisms of vascular smooth muscle in mesenteric arteries of NG-nitro L-arginine methyl ester (L-NAME)-induced hypertensive rats.Methods:Wistar rats were divided into three groups: control (C), hypertensive (H), and exercised hypertensive (EH). Hypertension was induced by administration of 20 mg/kg of L-NAME for 7 days prior to experimental protocols. The resistance exercise protocol consisted of 10 sets of 10 repetitions and intensity of 40% of one repetition maximum. The reactivity of vascular smooth muscle was evaluated by concentration‑response curves to phenylephrine (PHEN), potassium chloride (KCl) and sodium nitroprusside (SNP).Results:Rats treated with L-NAME showed an increase (p < 0.001) in systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP) compared to the initial period of induction. No difference in PHEN sensitivity was observed between groups H and EH. Acute resistance exercise reduced (p < 0.001) the contractile response induced by KCl at concentrations of 40 and 60 mM in group EH. Greater (p < 0.01) smooth muscle sensitivity to NPS was observed in group EH as compared to group H.Conclusion:One resistance exercise session reduces the contractile response induced by KCl in addition to increasing the sensitivity of smooth muscle to NO in mesenteric arteries of hypertensive rats.
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The effect of intraspecific competition for food on larvae and of food deprivation for 24 h on 2nd and 4th instars of Ascia monuste orseis (Godart, 1819) was investigated. Intraspecific competition for food during the immature phase leads to long pupation time, high larval mortality, reduced adult weight, and reduced number of eggs per female. In food deprivation experiments, the major differences in A. monuste orseis performance were long pupation time in the group that was deprived during the 2nd instar; and a negative effect on reproduction in the group that was deprived during the 4th instar, with reduced adult weight. Both food deprived periods tested are critical, and deprivation during the 2nd instar seems to have an effect as drastic as during the 4th instar because it directly affects larvae survival. Immatures can resist food deprivation for 24 h during the 2nd and 4th instars (low mortality), have a compensatory behaviour (high ingestion and biomass gain) during the 5th instar, and do not demonstrate cannibalistic behaviour during food deprivation.
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Differences in the phoresy of the mites Macrocheles muscaedomesticae (Scopoli, 1972) (Macrochelidae) and Uroseius sp. (Polyaspidae) on the house fly, Musca domestica (Linnaeus, 1758) and the similarities in their phoretic dispersal and parasitism are discussed, altogether with the effects on predator-prey interactions. The prevalence and intensity of phoresy in the mite species were significantly related to the attachment site on the hosts. The phoresy of Uroseius sp. was correlated with temperature but not with rainfall and relative humidity. Selective pressure in the environment resulted in displacement and the emergence of local and regional populations. These results suggest that in each habitat the populations will use different resources and will show several relationships with other species, as well as a selection for morphological and behavioral types.
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The goal of this study was to evaluate the effect of a high-carbohydrate diet (HC) and a high-protein diet (HP) on the metabolism of the crayfish Parastacus brasiliensis (Von Martens, 1869), collected in different seasons and maintained in the laboratory for 15 days. Crayfish were collected monthly from January 2002 to January 2004 at São Francisco de Paula, Southern Brazil, in Guarapirá stream. In the laboratory, the animals were kept submerged in aquariums under controlled conditions. They were fed ad libitum, for 15 days with either a HC or HP diet. At the end of this period, haemolymph samples were collected, as were hepatopancreas, gills, and abdominal muscle that were removed for determination of glycogen, free glucose, lipids, and triglycerides. The haemolymph samples were used for determination of glucose, proteins, lipids, and triglycerides. Statistical analysis (ANOVA) revealed significant seasonal differences in biochemical composition in crayfish maintained on HC or HP diets. Independent of the diets offered to the animals and the controlled conditions for 15 days, the indications of seasonality were unchanged. The observed changes seemed to be related to the reproductive period. Moreover, the HC diet increased all energy reserves in adult parastacids, which may aid in reproduction.
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I report on the occurrence of 16 species of birds in Rio Grande do Sul, southern Brazil, of which seven are new for the state - Accipiter superciliosus (Linnaeus, 1766), Brotogeris tirica (Gmelin, 1788), Hemitriccus margaritaceiventer (d'Orbigny & Lafresnaye, 1837), Phyllomyias griseocapilla Sclater, 1862, Saltator coerulescens Vieillot, 1817, Orthogonys chloricterus (Vieillot, 1819), and Sporophila lineola (Linnaeus, 1758) - and seven were previously known from unsubstantiated or poorly documented records - Ixobrychus exilis (Gmelin, 1789), Brotogeris chiriri (Vieillot, 1818), Coccyzus euleri Cabanis, 1873, Pulsatrix koeniswaldiana (Bertoni & Bertoni, 1901), Psilorhamphus guttatus (Ménétriès, 1835), Serpophaga griseicapilla Straneck, 2007, and Hemithraupis ruficapilla (Vieillot, 1818). Descriptive and natural history notes are presented for some of these species. The records of B. tirica, P. guttatus, P. griseocapilla, Myiozetetes similis (Spix, 1825), O. chloricterus, H. ruficapilla, and S. lineola represent significant southward range extensions of up to 300 km. Also, a new confirmed record of Myiarchus ferox (Statius Muller, 1776) is divulged. Finally, I argue that the Atlantic forests of north-eastern Rio Grande do Sul should be included in the Serra do Mar area of endemism (sensu SILVA et al., 2004) because of the presence of Orthogonys chloricterus, and comment on the possible range expansion of Myiozetetes similis, Sporophila lineola and other primarily tropical species in southern Brazil.