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Little Scope (little + scope)
Selected AbstractsInbreeding depression and genetic load of sexually selected traits: how the guppy lost its spotsJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 2 2003C. Van Oosterhout Abstract To date, few studies have investigated the effects of inbreeding on sexually selected traits, although inbreeding depression on such traits can play an important role in the evolution and ecology of wild populations. Sexually selected traits such as ornamentation and courtship behaviour may not be primary fitness characters, but selection and dominance coefficients of their mutations will resemble those of traits under natural selection. Strong directional selection, for instance, through female mate-choice, purges all but the most recessive deleterious mutations, and the remaining dominance variation will result in inbreeding depression once populations undergo bottlenecks. We analysed the effects of inbreeding on sexually selected traits (colour pattern and courtship behaviour) in the male guppy, Poecilia reticulata, from Trinidad, and found a significant decline in the frequency of mating behaviour and colour spots. Such effects occurred although the genetic basis of these traits, many of which are Y-linked and hemizygous, would be expected to leave relatively little scope for inbreeding depression. Findings suggest that these sexually selected traits could reflect the genetic condition or health of males, and thus may be informative mate-cue characters for female choice as suggested by the ,good genes' model. [source] Sex, Breastfeeding, and Marital Fertility in Pretransition ChinaPOPULATION AND DEVELOPMENT REVIEW, Issue 2 2007William Lavely Coital frequency is at the heart of the debate over low marital fertility in pretransition China. This study argues that coital frequency in contemporary China is indicative of sexual behavior in an earlier era. Frequency of intercourse is low in China relative to Europe, a natural outgrowth of a traditional family system and related sexual culture only partially transformed by a century of family revolution. Customary sexual behaviors and breastfeeding practices together shaped the Chinese historical fertility regime as they did the European. As explanations for China's low marital fertility, these proximate determinants leave little scope for the operation of fecundity-reducing malnutrition on the one hand, or deliberate fertility control on the other. The fertility regimes of other pretransition agrarian societies more closely resemble China's than Europe's, seeming to confirm a pattern of European demographic exceptionalism. [source] Maintaining a distinctive public administration: the Isle of Man civil service since 1962PUBLIC ADMINISTRATION, Issue 2 2002Paul Carmichael Emphasis on ,globalization' within academic literature is reflected in the contention within public administration that the prescriptions of the New Public Management are an inescapable fact of life from which states have little scope for resisting. However, variation persists both between and within countries. Since 1997, devolution within the UK and novel intergovernmental structures occasioned by the Belfast Agreement for Northern Ireland have transformed the territorial governance of the UK and the wider British Isles, providing further evidence of the differential impact of NPM. In seeking a better understanding of these differences, examination of the administrative arrangements of small communities or micro states can offer fascinating comparative insights into the workings of larger states, especially those with whom they enjoy a direct relationship. Frequently, however, small communities are overlooked in favour of studies of countries with more political weight. The micro states of the British Isles (namely, the Isle of Man and the Channel Islands) illustrate the point. However, with a few notable exceptions, relatively little is published. To correct this deficiency, this article seeks to explore developments in the Isle of Man, specifically its civil service. In so doing, the article aims to broaden our understanding of the changing governance not only of the Isle of Man, but also of the UK and beyond. [source] Corporate discourse and environmental performance in ArgentinaBUSINESS STRATEGY AND THE ENVIRONMENT, Issue 3 2008Diego A. Vazquez Abstract There is substantial research and policy interest in the relationship between firms and the natural environment, including how this relationship is influenced by regulators, international pressures, rival firms and stakeholder demands. With some exceptions, the ,softer' dimensions of environmental aspect management , how attitudes, beliefs and perceptions and the human factors drive corporate behaviour , have been understudied. The work that exists tends to be informal, and allows little scope for the statistical validation that is required for robust inference. This paper examines whether corporate values towards the environment affect a firm's environmental performance. It uses survey methods as well as content and discourse analyses of interview text and corporate reports and web sites to explore the links between managerial ,mindsets' and the environmental performance of the firms of which they are a part. Though the application is Argentina, the lessons learned can be generalized to other developing and industrialized countries. Copyright © 2006 John Wiley & Sons, Ltd and ERP Environment. [source] 4424: Visual acuity loss with healthy ageing: can it be reversed by wavefront laser?ACTA OPHTHALMOLOGICA, Issue 2010D ELLIOTT Purpose To consider what levels of "super acuity" might be achieved by the correction of ocular aberrations in older patients by wavefront corrected ophthalmic surgery. Note that when comparing visual acuity (VA) of older patients with VA in the young, the average optimal monocular visual acuity of a young subject is about 6/4 (decimal VA 1.50) and not the often quoted ,normal' figure of 20/20 (6/6 or 1.0 decimal). Methods Studies that attempted to isolate the cause(s) of deterioration in visual function with age in normal, healthy eyes were reviewed. Results The majority of studies suggest that the deterioration in visual function with age is primarily due to changes within the neural system rather than optical factors. In addition, several studies have shown increases in ocular aberrations with age, but this is only found when comparisons are made across age groups with fixed pupil sizes. When natural pupil sizes are considered, there is no change in aberrations with age because of age-related pupillary miosis Conclusion There appears to be little scope for ocular aberration correction to be used to counteract the loss of vision with age. Reduced vision in patients with cataract is primarily due to increased forward light scatter, and aberrations play a minor role in reducing vision. Intra-ocular lenses (IOLs) should be designed to keep ocular aberrations at a minimum after cataract surgery, but given that vision loss with age appears to be primarily due to neural changes, there seems little scope for IOLs to improve on the vision of phakic subjects under natural pupil conditions. [source] | ||||||||||