88 resultados para Educational success


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Objectives: The aim of this study was to assess the concomitant perioperative procedures, the causes of nasolacrimal duct obstruction, the success rate, and the complications associated with endonasal dacryocystorhinostomy (ENDCR).Methods: In this single-center retrospective study, 98 patients underwent 104 ENDCRs between January 1994 and February 2006. There were 78 patients with 84 nasolacrimal duct obstructions who were included in this study.Results: The overall functional success rate with improvement in symptoms was 94.9% for primary surgery (59 of 84 obstructions) and 63.6% for salvage surgery after failure of primary surgery performed in another hospital (25 of 84 obstructions). The mean follow-up time was 36.8 +/- 17.11 months. Primary surgery showed better results, with a complete success rate of 93.2%, than did salvage surgery, with a success rate of only 68%. Persistent symptoms, despite an open rhinostomy, were found in 1.7% of patients with primary surgery and in 12% of those with salvage surgery. Failure of ENDCR was observed in 3.4% of patients after primary surgery and in 20% after salvage surgery. We encountered only minimal perioperative complications, and these were essentially related to lacrimal intubation.Conclusions: Because of the possibility of treating concomitant sinonasal disorders, the cosmetic advantages, and the excellent results, ENDCR represents the procedure of choice for treating nasolacrimal duct obstructions. The main challenge lies in the exact preoperative assessment, as well as postoperative evaluation in case of failure.

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In order to investigate the determinants of effective population size in the socially monogamous Crocidura russula, the reproductive output of 44 individuals was estimated through genetic assignment methods. The individual variance in breeding success turned out to be surprisingly high, mostly because the males were markedly less monogamous than expected from previous behavioural data. Males paired simultaneously with up to four females and polygynous males had significantly more offspring than monogamous ones. The variance in female reproductive success also exceeded that of a Poisson distribution (though to a lesser extent), partly because females paired with multiply mated males weaned significantly more offspring. Polyandry also occurred occasionally, but only sequentially (i.e. without multiple paternity of litters). Estimates of the effective to census size ratio were ca. 0.60, which excluded the mating system as a potential explanation for the high genetic variance found in this shrew's populations. Our data suggest that gene flow from the neighbourhood (up to one-third of the total recruitment) is the most likely cause of the high levels of genetic diversity observed in this shrew's subpopulations.

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We investigated how territory quality, settlement date and morphometry affected several components of yearly breeding success of a Swiss population of Savi's Warblers Locustella luscinioides. Territories occupied by males differed from unoccupied sites of similar size and location by having higher and denser reeds, a more extensive straw litter, and a thicker cover of dead sedge leaves. Territories with these characteristics were the ones first chosen by males upon spring arrival. These males, however, did not differ in morphometry from those that arrived later. Availability of suitable nesting sites; rather than food availability, appears to be an important choice criterion for territories. Early arriving males had higher breeding success than late males because of a higher mating success and more successful clutches. The positive correlation between male breeding success and territory quality was thus mediated through their common dependence on occupancy date. Female breeding success decreased with the date of first-clutch laying, mainly because late-nesting females fledged fewer broods. Breeding success in either sex did not correlate with morphometry. Our results provide clear support for territory choice by males, but not for mate or territory choice by females, and show the crucial role played by individual settlement date on many aspects of the breeding cycle of both sexes. We propose a lottery model of mate choice. arriving females obtain the best available territories even without choosing mates or territories; since males occupy territories sequentially and in order of decreasing quality, the few unpaired males available at any moment also occupy the best available territories.

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We studied for the first time the occurrence of multiple paternity, male reproductive success, and neonate survival in wild, low-density adder (Vipera berus) populations using 13 microsatellite loci. Paternity was assigned for 15 clutches, collected during 3 years. Our data demonstrated that multiple paternity can occur at a high level (69%) in natural populations of V. berus, even if the density of adults is low. The high proportion of multiple sired clutches was comparable to the proportion observed in captive populations. Male reproductive success significantly increased with body length, and only the largest males successfully sired entire clutches. Finally, no relationship was detected between the number of fathers per clutch and neonate survival. These results suggest that multiple matings could be beneficial in populations with high level of inbreeding or low male fecundity.

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Ectoparasites are common in most bird species, but experimental evidence of their effects on life-history traits is scarce. We investigated experimentally the effects of the hematophagous hen flea (Ceratophyllus gallinae) on timing of reproduction, nest-site choice, nest desertion, clutch size, and hatching success in the great tit (Parus major). When great tits were offered a choice on their territory between an infested and a parasite-free nest-box, they chose the one without parasites. When there was no choice, the great tits in a territory containing an infested nest-box delayed laying the clutch by 11 days as compared with the birds that were offered a parasite-free nesting opportunity. The finding that there was no difference in phenotypic traits related to dominance between the birds nesting in infested boxes and birds nesting in parasite-free boxes suggests that the delay is not imposed by social dominance. Nest desertion between laying and shortly after hatching was significandy higher in infested nests. There was no difference between infested and parasite-free nests in clutch size, but hatching success and hence brood size at hatching were significantly smaller in infested nests. Nest-box studies of great tits have been seminal in the development of evolutionary, ecological, and behavioral theory, but recently a polemic has arisen in the literature about the validity of the conclusions drawn from nest-box studies where the naturally occurring, detrimental ectoparasites are eliminated by the routine removal of old nests between breeding seasons. Our study suggests that this criticism is valid and that the evaluation of the effects of ectoparasites may improve our understanding of behavioral traits, life-history traits, or population dynamics

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I present an optimisation model that links paternal investment, male display and female choice. Although deviced for sticklebacks, it readily applies to other fish with male guarding behaviour. It relies on a few basic assumptions on the ways hatching success depends on paternal investment and clutch size, and male survival on paternal investment and signaling. Paternal investment is here a state-dependent decision, and signal a condition-dependent handicap by which males inform females of how much they are willing to invest. Series of predictions are derived on female and male breeding strategies, including optimal levels of signaling and paternal investment as functions of clutch size, own condition, and residual reproductive value, as well as alternative strategies such as egg kleptoparasitism. Some predictions already have empirical support, for which the present model provides new interpretations. Other might readily be tested, e.g. by simple clutch-size manipulations.

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Contemporary thoracic and cardiovascular surgery uses extensive equipment and devices to enable its performance. As the specialties develop and new frontiers are crossed, the technology needs to advance in a parallel fashion. Strokes of genius or problem-solving brain-storming may generate great ideas, but the metamorphosis of an idea into a physical functioning tool requires a lot more than just a thinking process. A modern surgical device is the end-point of a sophisticated, complicated and potentially treacherous route, which incorporates new skills and knowledge acquisition. Processes including technology transfer, commercialisation, corporate and product development, intellectual property and regulatory routes all play pivotal roles in this voyage. Many good ideas may fall by the wayside for a multitude of reasons as they may not be marketable or may be badly marketed. In this article, we attempt to illuminate the components required in the process of surgical innovation, which we believe must remain in the remit of the modern-day thoracic and cardiovascular surgeon.

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The student´s screening made by schools corresponds to a regulatory mechanism for school inclusion and exclusion that normally overlaps the parental expectations of school choice. Based in "Parents survey 2006" data (n=188.073) generated by the Chilean Educational Ministry, this paper describe the parents reasons for choosing their children's school, and school´s criteria for screening students. It concludes that the catholic schools are the most selective institutions and usually exceed the capacity of parental choice. One of the reasons to select students would be the direct relationship between this practice and increasing the average score on the test of the Chilean Educational Quality Measurement System (SIMCE).

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Only a few studies, and mostly in temperate climates in Europe, have examined the breeding and diet of long-eared owls (Asia otus) compared to studies of cavity-breeding owls, possibly because of the difficulties in reaching the nests of the former. Here we studied a population of long-eared owls, monitoring the diet of breeding owls and that of owls at a communal roost, every two to three months during 2006 -2009, in a semi-arid region in Israel. It was found that the studied owls produced more young than in most countries in Europe. Diet was not associated with breeding parameters of the owls, whereas laying date was negatively correlated with both clutch size and number of nestlings. We found that more social voles (Microtus socialis) and fewer birds and house mice (Mus musculus) made up the diet at nests than that of adults at the roosts. The diet and breeding of long-eared owls in Israel differ from that in Europe, with birds and mice comprising an important part of the diet, in addition to voles.

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The human behavior is giving the entire picture of a person. The behavior is based on a complex combination of personal innate factors, experience and education and the social network within which the individual is integrated. Each moment the complex individual factors face external and internal environmental aspects which in turn, generate proactive and retroactive reactions. The adoption process is an important and challenging social experiment, bringing to the adopted child a new affiliation, social network, experiences and educational standards. This comes in his/her life after the trauma of losing his biological affiliation and social and emotional support. Which are the significant characteristics of the adopted child's behavior? Which are the behavioral characteristics of the adoptive child that guarantee the success of the domestic adoptions in Romania? These are the questions we are going to answer here based on the research done within FISAN(6) project. The 32 children, 11-16 years old, adopted by Romanian families, during the early ages (0-4 years), were evaluated with complex evaluation tools for children and parents. The adoptive families participating in the research live in the Western counties of Romania.Successful adoption is defined as secure attachment of the adopted child. The conclusions emphasize the importance of: the pro-social behavior, the loving behavior showed to the parents, the assertive behavior, the differentiations between parents and people outside the family, and between the two parents, and the humor. These behaviors displayed by the adopted children are the ingredients of a successful integration within the adoptive family.