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31.
The purpose of this study is to explore the conflict between use and preservation in national parks policy as seen through the mission statement of the National Parks Service. The histories of the national parks were qualitatively coded in order to further explore this controversy, or what we have termed “mission rivalry”.  相似文献   
32.
BackgroundSevere perineal tears sustained during childbirth cause significant distress and morbidity amongst women. The objective of this study was to compare the use of straight scissors for cutting an episiotomy with the use of curved scissors, which are designed to curve away from the anal sphincter.MethodsWe used a single-centre, randomised feasibility trial. The intervention was the use of curved scissors. Women were recruited during a prenatal visit and randomised in the delivery suite, when it became clear that an episiotomy was required. The feasibility outcomes were the proportion of women able to be recruited, randomised and followed up. We also calculated the incidence of obstetric anal sphincter injury when either straight or curved scissors were used to cut an episiotomy. Other outcomes assessed were pain, length of hospital stay, perineal infection and perineal dehiscence.ResultsOf the 155 patients recruited in the prenatal period, only 20 (12.9%) were eventually randomised at birth. The main reasons for the high loss were that women either did not have a vaginal delivery (38, 24.5%), or they did not need an episiotomy (72, 46.5%). Rates of obstetric anal sphincter injury and other outcomes were similar between groups.DiscussionAnal sphincter injury during childbirth remains an important problem. Although the use of curved scissors provides a theoretical solution, we found that the high attrition rate made feasibility of conducting a suitably powered, randomised trial using the current design untenable. Alternative strategies have been suggested to make any future study more viable.  相似文献   
33.
This is a story of two people with different philosophies concerning use of land and attitudes towards animals. What makes their situation unique is that they share abutting property and live on the same road in a small village in Maine. Phil owns the house and land on which he grew up and has always hunted the surrounding land, including the property more recently acquired by Marie. Marie emigrated from Massachusetts with the intention to create a sanctuary for animals. Their polarized views have resulted in strife between them and illustrate the conflict between hunters and non-hunters in Maine.  相似文献   
34.
While all children may be the victims of abuse, disabled children are particularly vulnerable. This paper explores the views of professionals working with children using alternative/augmented communication systems on the issues relating to communication about abuse. Interviews were carried out with 20 staff from eight establishments for disabled children across Scotland. It describes the range of alternative/augmented communication systems used and the barriers to communication about abuse. Staff generally accepted the importance of providing the appropriate vocabulary in augmented communication systems, but systems that provide such vocabulary were not widely used. Staff considered that a major difficulty concerned the level of understanding disabled children might have about concepts of abuse. They were unsure how the appropriate vocabulary could be introduced in a natural way and how links could be made between the signs and their meanings. Staff saw themselves as those most able to protect the children, but it was felt that discovery of abuse was more likely to come from them noticing physical signs, behaviour or mood changes than from the child communicating explicitly about abuse. The need for appropriate training and increased coordination between social work, health and education is highlighted. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
35.
ABSTRACT

This paper explores the challenges of outsidership faced by multinational companies (MNCs) accessing emerging economies. The paper departs from popular conceptualisations of culture drawing instead on social identity theory as part of an institutions-based view, to explain how employing a singularities approach can allow the identification of commonalities of Indianness and Australianness that can be leveraged to ameliorate negative socially embedded business norms that pose a challenge to MNC success in emerging economies. This study shows that despite recognised formal (regulatory) and informal (cultural) differences, managers of Australian MNCs operating in India were able to innovatively identify and exploit cultural commonalties/singularities to ease cultural adjustment and mitigate intergroup conflict, allowing them to achieve an innovative institutional fit. The paper discusses how, using this approach, sole-venture MNCs can access many of the benefits provided by collaborative entry modes while preserving MNC identity. We further propose that the singularities approach can provide a valuable starting point to develop culturally appropriate competence training initiatives.  相似文献   
36.
Tree algorithms are a well-known class of random access algorithms with a provable maximum stable throughput under the infinite population model (as opposed to ALOHA or the binary exponential backoff algorithm). In this article, we propose a tree algorithm for opportunistic spectrum usage in cognitive radio networks. A channel in such a network is shared among so-called primary and secondary users, where the secondary users are allowed to use the channel only if there is no primary user activity. The tree algorithm designed in this article can be used by the secondary users to share the channel capacity left by the primary users.

We analyze the maximum stable throughput and mean packet delay of the secondary users by developing a tree structured Quasi-Birth Death Markov chain under the assumption that the primary user activity can be modeled by means of a finite state Markov chain and that packets lengths follow a discrete phase-type distribution.

Numerical experiments provide insight on the effect of various system parameters and indicate that the proposed algorithm is able to make good use of the bandwidth left by the primary users.  相似文献   

37.
We examined whether adolescent sexual abstinence predicts better adult mental health. 1,917 adolescents, recruited from middle schools at age 13, were surveyed at ages 13, 18, 23, and 29. In bivariate analyses, adolescent sexual abstinence was associated with better mental health at age 29 for females, but not males; three adolescent factors, educational prospects, family bonding, and unconventionality were investigated as explanatory variables of this relationship. The abstinence-mental health relationship was nonsignificant when educational prospects was included in multivariate models, and marginally significant when family bonding and unconventionality were included; all three explanatory factors accounted for significant proportions of the variance in adult mental health. Girls who are uninvolved in school, have weak family backgrounds, and exhibit unconventionality may have poor adult mental health, whether or not they abstain from sex in adolescence. Interventions that strengthen adolescents' connections to families and schools may reduce risk for long-term mental health problems.  相似文献   
38.
As canons for trustworthiness developed explicitly in the discourse of qualitative inquiry, the emphasis was on procedural matters rather than fundamentally relational ones. A nod was made to the relational in such strategies as “member checks” but the issues of how the evaluator actually relates to participants and to the larger communities of practice and discourse—matters subsumed under moral principles and ethical standards—were often marginalized. This chapter posits that the first consideration in designing and conducting rigorous evaluation inquiry, and in critiquing the results of any research, should be the study's trustworthiness. Judging a study's trustworthiness, however, should focus on much more than procedural matters; it should also rely on moral principles and ethical standards which specifically address how we relate to an evaluation's participants. Central to these considerations are cross-cultural sensibilities about the nuanced meanings associated with any principles and standards. The chapter provides a theoretical framework for this position and offers two illustrative examples in the form of dialogues.  相似文献   
39.
University research administrators have been generally ignored in basic studies of research integrity. Hensley noted that research administrators are "essential... to the achievement of the specific missions of postsecondary institutions... and to science and the academic infrastructure". The following study sought to extend the scope of research on research integrity to research administrative structures with a new instrument called the Research Environment Norm Inventory or RENI. University research administrators and their professional association were targeted for data collection. Evidence suggested that research administration in the United States supports integrity in the research environment through: (1) respect for community; (2) respect for institutional boundaries; (3) professionalism; (4) respect for authority structures; (5) sensitivity to system conflicts. The study suggested that integrity structures are dictated largely by the institutional settings and environments.  相似文献   
40.
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