469 resultados para Abstinence Survivorship


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Research carried out in several Anglo-Saxon countries shows that many undergraduates identify oral sex and anal sex as examples of abstinent behaviour, while many others consider kissing and masturbation as examples of having sex. The objective of this research was to investigate whether a sample of Spanish students gave similar replies. Seven hundred and fifty undergraduates (92% aged under 26, 67.6% women) produced examples or definitions of the term ‘abstinence’. Spanish students made similar errors to those observed in the Anglo-Saxon samples, in that behaviours that were abstinent from a preventive point of view (masturbating and sex without penetration) were not considered as such, while a number of students reported oral sex as abstinent behaviour. The results suggest that the information on risky and preventive sexual behaviour should cease to use ambiguous or euphemistic expressions and use vocabulary that is clear and comprehensible to everyone

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Long-distance migrants wintering in tropical regions face a number of critical conservation threats throughout their lives, but seasonal estimates of key demographic parameters such as winter survival are rare. Using mist-netting-based mark-recapture data collected in coastal Costa Rica over a six-year period, we examined variation in within- and between-winter survivorship of the Prothonotary Warbler (Protonotaria citrea; 753 young and 376 adults banded), a declining neotropical habitat specialist that depends on threatened mangrove forests during the nonbreeding season. We derived parallel seasonal survivorship estimates for the Northern Waterthrush (Seiurus noveboracensis; 564 young and 93 adults banded), a cohabitant mangrove specialist that has not shown the same population decline in North America, to assess whether contrasting survivorship might contribute to the observed differences in the species’ population trajectories. Although average annual survival probability was relatively similar between the two species for both young and adult birds, monthly estimates indicated that relative to Northern Waterthrush, Prothonotary Warblers exhibited: greater interannual variation in survivorship, especially within winters; greater variation in survivorship among the three study sites; lower average between-winter survivorship, particularly among females, and; a sharp decline in between-winter survivorship from 2003 to 2009 for both age groups and both sexes. Rather than identifying one seasonal vital rate as a causal factor of Prothonotary Warbler population declines, our species comparison suggests that the combination of variable within-winter survival with decreasing between-winter survival demands a multi-seasonal approach to the conservation of this and other tropical-wintering migrants.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Os tubarões enfrentam muitos obstáculos para sobreviver nos primeiros anos de vida e muitas espécies ocupam áreas de berçário. Embora estimativas de sobrevivência, particularmente para jovens, sejam essenciais para acessar, monitorar e manejar efetivamente populações animais, existem poucos cálculos destas estimativas para populações de tubarões e poucas estimativas baseadas em métodos diretos para estes animais em suas áreas de berçário. Métodos de marcação e recaptura foram utilizados no presente estudo para estimar o tamanho populacional e a sobrevivência de jovens tubarões-limão (Negaprion brevirostris) em uma área de berçário na Reserva Biológica do Atol das Rocas, Brasil. Os indivíduos foram amostrados entre 1999 e 2003 e as estimativas de tamanho populacional variaram entre 12 a 100 indivíduos jovens e a taxa de sobrevivência entre 24 e 54%, com média de 44,6% durante o período de amostragem mais robusto. A população destes tubarões jovens diminuiu ao longo de nosso estudo, ainda que as taxas de sobrevivência tenham aumentado durante o mesmo período. Mesmo um nível moderado de pesca e a remoção de fêmeas maduras em áreas adjacentes podem afetar dramaticamente pequenas populações de tubarões num berçário pequeno e isolado como o Atol das Rocas. As taxas de sobrevivência e tamanho populacional relativamente mais baixos em Rocas podem ser resultado das diferenças nas características físicas deste berçário, comparadas a outros utilizados pela espécie no Atlântico norte-ocidental. Tais parâmetros comparativamente mais baixos no Atol das Rocas sugerem a fragilidade da população jovem de tubarões-limão neste berçário.

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Alcoholism is rampant in modern society and some antioxidant compound could perhaps be useful to reduce the damage done by alcohol consumption and abstinence. The present study was undertaken to investigate the association of N-acetylcysteine (NAC) intake, alcoholism, and alcohol abstinence on lipid profile, in vivo low-density lipoprotein (LDL) oxidation, oxidative stress, and antioxidant status in serum and liver of rats. Initially, male Wistar 30 rats were divided into two groups: (C, N = 6) given standard chow and water; (E, N = 24) receiving standard chow and aqueous ethanol solution in semi-voluntary research. After 30 days of ethanol exposure, (E) group was divided into four subgroups (N = 6/group): (E-E) continued drinking 30% ethanol solution; (E-NAC) drinking ethanol solution containing 2 g/L NAC (AB) changed ethanol solution to water; (AB-NAC) changed ethanol to aqueous solution 2 g/L NAC. After 15 days of the E-group division, E-E rats had higher serum alanine transaminase, lower body weight, and surface area, despite higher energy intake than C. E-E rats had also lower feed efficiency, dyslipidemia with enhanced triacyl glycerol, very low-density lipoprotein (VLDL), lipid hydroperoxide (LH) and in vivo oxidized-LDL (ox-LDL). AB, E-NAC, and AB-NAC rats ameliorated serum oxidative stress markers and normalized serum lipids. E-E rats had higher hepatic LH and lower reduced glutathione (GSH)/oxidized glutathione (GSSG) ratio than C, indicating hepatic oxidative stress. AB and E-NAC rats normalized hepatic LH, GSSG, and the GSH/GSSG ratio, compared to E-E. AB-NAC rats had the lowest serum ox-LDL, hepatic LH levels, and the highest GSH reductase activity in hepatic tissue. In conclusion, the present study brought new insights into alcohol consumption, because ethanol exposure enhanced serum in vivo ox-LDL, as well as serum and hepatic oxidative stress. N-acetylcysteine offers promising therapeutic value to inhibit ethanol-induced adverse effects. Ethanol withdrawal had beneficial effects on serum lipids, but was more effective when coupled with NAC supplementation. Ethanol abstinence and NAC intake interact synergistically, improving serum lipids and hepatic antioxidant defenses. (c) 2009 Elsevier B.V. All rights reserved.

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Transplants of incipient colonies of the fire ant, Solenopsis invicta into areas in which mature colonies had been eliminated did not result in higher rates of success than in areas in which mature colonies were present. However for both types of sites, Pogonomyrmex (Ephebomyrmex) nagelli colonies were found in cleared sites used for transplants, with the number of translocated P. nagelli nests higher in areas which had not been treated with Mirex for S. invicta colony reduction. These results suggest that small colonies may be displaced by larger colonies of other species.

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In this study, known-age workers of Agelaia pallipes (Olivier) were introduced into a colony maintained in the laboratory and the effects of age polyethism on the worker life span were observed. As in other Neotropical swarm-founding wasps, the results showed that younger workers remained on different places inside the nest performing activities related to the brood and nest maintenance, while risky tasks such as foraging were performed by older workers. Furthermore, the start of foraging activities had a significant effect on worker mortality.

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Adolescence has been linked to greater risk-taking and novelty-seeking behavior and a higher prevalence of drug abuse and risk of relapse. Decreases in cyclic adenosine monophosphate response element binding protein (CREB) and phosphorylated CREB (pCREB) have been reported after repeated cocaine administration in animal models. We compared the behavioral effects of cocaine and abstinence in adolescent and adult mice and investigated possible age-related differences in CREB and pCREB levels. Adolescent and adult male Swiss mice received one daily injection of saline or cocaine (10 mg/kg, i.p.) for 8 days. On day 9, the mice received a saline injection to evaluate possible environmental conditioning. After 9 days of withdrawal, the mice were tested in the elevated plus maze to evaluate anxiety-like behavior. Twelve days after the last saline/cocaine injection, the mice received a challenge injection of either cocaine or saline, and locomotor activity was assessed. One hour after the last injection, the brains were extracted, and CREB and pCREB levels were evaluated using Western blot in the prefrontal cortex (PFC) and hippocampus. The cocaine-pretreated mice during adolescence exhibited a greater magnitude of the expression of behavioral sensitization and greater cocaine withdrawal-induced anxiety-like behavior compared with the control group. Significant increases in CREB levels in the PFC and hippocampus and pCREB in the hippocampus were observed in cocaine-abstinent animals compared with the animals treated with cocaine in adulthood. Interestingly, significant negative correlations were observed between cocaine sensitization and CREB levels in both regions. These results suggest that the behavioral and neurochemical consequences of psychoactive substances in a still-developing nervous system can be more severe than in an already mature nervous system

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Carotenoid-based sexual ornaments are hypothesized to be reliable signals of male quality, based on an allocation trade-off between the use of carotenoids as pigments and their use in antioxidant defence against reactive oxygen species. Carotenoids appear to be poor antioxidants in vivo, however, and it is not clear whether variation in ornament expression is correlated with measures of oxidative stress (OXS) under natural conditions. We used single-cell gel electrophoresis to assay oxidative damage to erythrocyte DNA in the common yellowthroat (Geothlypis trichas), a sexually dichromatic warbler in which sexual selection favours components of the males’ yellow ‘bib’. We found that the level of DNA damage sustained by males predicted their overwinter survivorship and was reflected in the quality of their plumage. Males with brighter yellow bibs showed lower levels of DNA damage, both during the year the plumage was sampled (such that yellow brightness signalled current OXS) and during the previous year (such that yellow brightness signalled past OXS). We suggest that carotenoid-based ornaments can convey information about OXS to prospective mates and that further work exploring the proximate mechanism(s) linking OXS to coloration is warranted.

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The aims of the study were (1) to determine the cumulative two to twenty-year survivorship of the hip after open reduction and internal fixation of displaced acetabular fractures, (2) to identify factors predicting conversion to total hip arthroplasty or hip arthrodesis, and (3) to create a predictive model that calculates an individual's probability of early need for total hip arthroplasty or hip arthrodesis.

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Effects of the dihydropyridine, nimodipine, an antagonist at L-type calcium channels, on the memory loss in rats caused by long term alcohol consumption were examined. Either a single dose of nimodipine or 2 weeks of repeated administration was given prior to withdrawal from 8 months of alcohol consumption. Memory was measured by the object recognition test and the T maze. Both nimodipine treatments prevented the memory deficits when these were measured between 1 and 2 months after alcohol withdrawal. At the end of the memory testing, 2 months after cessation of chronic alcohol consumption, glucocorticoid concentrations were increased in specific regions of rat brain without changes in plasma concentrations. Both nimodipine treatment schedules substantially reduced these rises in brain glucocorticoid. The data indicate that blockade of L-type calcium channels prior to alcohol withdrawal protects against the memory deficits caused by prolonged alcohol intake. This shows that specific drug treatments, such as nimodipine, given over the acute withdrawal phase, can prevented the neuronal changes responsible for subsequent adverse effects of long term consumption of alcohol. The results also suggest the possibility that regional brain glucocorticoid increases may be involved in the adverse effects of long term alcohol intake on memory. Such local changes in brain glucocorticoid levels would have major effects on neuronal function. The studies indicate that L-type calcium channels and brain glucocorticoid levels could form new targets for the treatment of cognitive deficits in alcoholics.

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BACKGROUND Although periacetabular osteotomy (PAO) for developmental dysplasia of the hip (DDH) provides conceptual advantages compared with other osteotomies and reportedly is associated with joint survivorship of 60% at 20 years, the beneficial effect of proper acetabular reorientation with concomitant arthrotomy and creation of femoral head-neck offset on 10-year hip survivorship remains unclear. QUESTIONS/PURPOSES We asked the following questions: (1) Does the 10-year survivorship of the hip after PAO improve with proper acetabular reorientation and a spherical femoral head; (2) does the Merle d'Aubigné-Postel score improve; (3) can the progression of osteoarthritis (OA) be slowed; and (4) what factors predict conversion to THA, progression of OA, or a Merle d'Aubigné-Postel score less than 15 points? METHODS We retrospectively reviewed 147 patients who underwent 165 PAOs for DDH with two matched groups: Group I (proper reorientation and spherical femoral head) and Group II (improper reorientation and aspherical femoral head). We compared the Kaplan-Meier survivorship, Merle d'Aubigné-Postel scores, and progression of OA in both groups. A Cox regression analysis (end points: THA, OA progression, or Merle d'Aubigné-Postel score less than 15) was performed to detect factors predicting failure. The minimum followup was 10 years (median, 11 years; range, 10-14 years). RESULTS An increased survivorship was found in Group I. The Merle d'Aubigné-Postel score did not differ. Progression of OA in Group I was slower than in Group II. Factors predicting failure included greater age, lower preoperative Merle d'Aubigné-Postel score, and the presence of a Trendelenburg sign, aspherical head, OA, subluxation, postoperative acetabular retroversion, excessive acetabular anteversion, and undercoverage. CONCLUSIONS Proper acetabular reorientation and the creation of a spherical femoral head improve long-term survivorship and decelerate OA progression in patients with DDH.