Este estudo é parte de um projeto mais amplo que investiga as diferenças individuais no processo de adaptação de trabalhadores aos esquemas temporais de trabalho a que estão submetidos. As diferentes estratégias dos trabalhadores para se adaptar ao trabalho noturno têm sido amplamente investigadas com o objetivo de se conhecer modos de lidar melhor com a organização temporal do trabalho. Neste trabalho foi realizado um estudo de uma possível estratégia de adaptação ao débito de sono provocado pelo trabalho noturno em uma população de mulheres: a fragmentação do sono, ou seja, a realização de mais de um episódio de sono ao longo das 24 horas. A princípio, foram identificadas trabalhadoras que se auto-avaliaram como bem adaptadas ao esquema de trabalho. A avaliação da adaptação foi realizada através de um formulário construído a partir dos depoimentos das próprias trabalhadoras acerca do impacto do trabalho noturno. O acompanhamento do ciclo vigília-sono das trabalhadoras, por dez semanas consecutivas, através de protocolos de atividades preenchidos por elas, permitiu identificar aquelas que fragmentavam o sono e posteriormente confrontar esse resultado com a autoavaliação da adaptação das trabalhadoras. Nessa última etapa, a amostra desse estudo consistia de 24 mulheres que trabalhavam em uma indústria farmacêutica de segunda a sexta-feira das 22:00 às 06:00. Na ocasião da pesquisa elas tinham entre 20 e 40 anos de idade. Para verificar a influência da fragmentação regular do sono foi realizado um segundo estudo, em laboratório, onde foi possível controlar a fragmentação do sono. Neste estudo foram avaliados sujeitos submetidos a um regime simulado de emergência de trabalho, envolvendo drástica redução do sono. Esta avaliação foi realizada com voluntários submetidos a uma fragmentação forçada de sono. Os resultados do estudo em laboratório mostraram que a fragmentação regular do sono não causa sonolência maior do que um único episódio de sono. O estudo no campo revelou que para a maioria das trabalhadoras que dormem mais de um episódio de sono ao longo das 24 horas e que se auto-avaliaram como bem-adaptadas, a fragmentação do sono pode ser interpretada como uma estratégia de adaptação. Entretanto, há trabalhadoras que apesar de se auto-avaliarem como bem-adaptadas não fragmentam o sono. Conclue-se, portanto, que não há um único padrão de sono adequado para todos os trabalhadores e a variabilidade individual deve ser levada em consideração antes de propor uma específica estratégia de sono como estratégias de adaptação ao trabalho. / This work is part of a larger project designed to search for individual differences relevant to adaptation of workers submitted to unusual work schedules. The different strategies of adaptation have been investigated in order to improve coping with nightwork. In this present study we report an investigation about sleep fragmentation (more than one sleep episode a day) as a strategy of adaptation to the sleep deficit caused by work schedule in female nightworkers. First of all, female nightworkers who evaluated themselves as well adapted were identified. This evaluation was made through a form based on interviews. The follow-up of workers\' sleep-wake cycle with sleep logs filled out by themselves for ten consecutive weeks permitted the identification of workers who showed sleep fragmentation. This result was compared with the adaptation\' scores obtained from the forms. In this last part of the study the sample was composed by 24 females who worked at a pharmaceutical plant from Monday to Friday from 22:00 to 06:00. They were between 20 and 40 years old. To verify the influence of regular sleep fragmentation on work adaptation a lab study was carried out. In this study we analyzed subjects submitted to a simulation of an emergency work condition with sleep reduction. This evaluation was done with volunteers submitted to a forced sleep fragmentation. The results from this lab study showed that the sleepiness caused by regular sleep fragmentation is not greater than when it is caused by a single sleep episode. The field study showed that sleep fragmentation can be understood as an adaptation strategy for women who both fragmented their sleep and identified themselves as well adapted. However, there were women who in spite of considering themselves well adapted, did not show sleep fragmentation. It can be concluded that there is not an ideal sleep pattern for all of the subjects and that individual variability should be taken in to account before proposing a specific sleep strategy as recommendation to cope with nightwork.

Assemblages of algae are altered by both bottom - up ( e.g. nutrient availability ) and top - down ( e.g. herbivory ) processes. As a result of the increasing human population in coastal areas, massive changes are forecast to benthic habitats in response to increasing coastal nutrient concentrations and a reduction in consumers. To identify the scales over which nutrients may have an effect, abundance of turf - forming algae growing as epiphytes on kelp ( Ecklonia radiata ) were related to water nutrient concentration across temperate Australia. In general, the percentage cover of epiphytes was greatest at sites with the greatest nutrient concentrations. By experimentally elevating mean nitrate concentration from the low 0.064 ± 0.01 µmol L [superscript - 1 ] to 0.121 ± 0.04 µmol L [superscript - 1 ], which was still only ~ 5 % of that measured on a more eutrophic coast, I was able to increase the percentage cover of epiphytes to match those seen on nutrient rich coasts, despite not matching the nutrient concentrations on those coasts. Hence, it appears that the effects of elevated nutrients will be disproportionately large on relatively oligotrophic coasts. Nutrient concentrations were also experimentally elevated to test whether the presence of an algal canopy or molluscan grazers were able to counter the effects of nutrient enrichment on algal assemblages. The loss of canopy - forming algae is likely to be a key precursor to nutrient driven changes of benthic habitats, because nutrients had no direct effect on algal assemblages in the presence of canopy - forming algae. In the absence of canopy - forming algae, space was quickly monopolised by turf - forming algae, but in the presence of elevated nutrients grazers were able to reduce the monopoly of turf - forming algae in favour of foliose algae. This switch in relative abundance of habitat may reflect greater consumption of nutrient rich turf - forming algae by grazers, possibly creating more space for other algae to colonise. Importantly, greater consumption of turf - forming algae in the presence of elevated nutrients may act as a mechanism to absorb the disproportionate effect of nutrients on oligotrophic coasts. In southern Australia, canopy - forming algae have a negative impact on the abundance of turf - forming algae. To assess the mechanisms by which an algal canopy may suppress turf - forming algae, abrasion by the canopy and water flow were experimentally reduced. Abrasion by the canopy reduced the percentage cover and biomass of turf - forming algae. In contrast to predictions, biomass and percentage cover of turf - forming algae were also reduced when water flow was reduced. Light intensity was substantially reduced when there was less water flow ( because of reduced movement in algal canopy ). However, the reduction in available light ( shading ) did not account for all of the observed reduction in biomass and percentage cover of turf - forming algae, suggesting that other factors are modified by water flow and may contribute to the loss of turf - forming algae. Habitat loss and fragmentation are well known to affect the diversity and abundance of fauna in habitat patches. I used experimental habitats to assess how fragmentation of turf habitats affects the diversity and abundance of two taxa of macroinvertebrates with different dispersal abilities. I established that increased isolation of habitats reduced the species richness and abundance of invertebrates with slow rates of dispersal, while the species richness and abundance of invertebrates with fast rates of dispersal were greatest in habitats that were far apart. In summary, this thesis provides an insight into some of the impacts associated with human populations in coastal areas, namely increased nutrient inputs, loss of grazers ( e.g. harvesting ), and loss of canopy algae and fragmentation of habitats. I show that increased nutrient concentrations in coastal waters can alter the relative abundance of algal species, and that some effects of elevated nutrients can be absorbed by the presence of grazers. I also show that elevated nutrients have no effect on algal assemblage in the presence of canopy - forming algae, and that canopies can suppress the colonisation of turf - forming algae. Finally, I show that the fragmentation of turf habitats affects taxa of invertebrates with different dispersal abilities in different ways. Whilst the contemporary ecology of much of the temperate Australian subtidal coast is considered to be relatively unaffected by human activity, this thesis shows that changes to top - down and bottom - up processes could have large consequences for habitats and their inhabitants. / Thesis (Ph.D.)--School of Earth and Environmental Sciences, 2005.

This dissertation is a qualitative examination of how the anti-dam movements, with so many disadvantages, are able to pursue their goals in a hybrid democratic political system in Thailand. This dissertation tries to prove that the extra-bureaucratic influence, which emerges from the anti-dam movements are gaining their foothold in the dam politics of Thailand and become a major cause in increase in pluralism in the fragmented authoritarian regime of Thailand. There are two major arguments in the dissertation: Firstly, FA framework, which has already been proved applicable to China by Lieberthal and Oksenberg in 1988 and by Metha in 2008 is also applicable to Thailand. Second argument is that the success of anti-dam movement should not be judged simply by the ability to cancel the project. If we only consider the ability to cancel the project, we may either overestimate or underestimate the ability of anti-dam movement. However, it does not mean that the ability to cancel the dam project does not count at all or should be excluded completely because it still proves the short-term success, which means that the project is cancelled as that moment. In sum, the ¡§success¡¨ of the anti-dam movement mentioned in this dissertation is the ability to transform the state¡¦s decision-making process for the dam project into the direction of more pluralism and less of authoritarianism so that individuals and groups both inside and outside the traditional arenas of policymaking have increasing role in the policy process. Thus the ability to cancel the dam project is an additional indicator not the main one. This view is illustrated through the four case studies: Bhumibol Dam, Nam Choan Dam, Pak Mun Dam, and Kaeng Sua Ten Dam.

Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.

Despite increasing publicity, habitat loss and fragmentation remain a serious threat to biodiversity. The main objectives of this research were (i) to study the effects of forest fragmentation on the distribution and abundance of resident birds in the fragmented littoral forests of southeastern Madagascar and temperate woodlands of southeastern Australia at three spatial scales (patch, landscape and regional) and (ii) to place the results of these case studies within the realms of the equilibrium theory of island biogeography and its descendent theories, to ascertain whether it is appropriate to use these theories to derive conservation scenarios within these threatened regions. Deforestation of Madagascar's remaining forests is considered a global concern due to both its current high intensity and the small amount of forest claimed to be remaining on the island. Surprisingly, very few studies have considered the impacts of forest fragmentation on bird diversity in Madagascar. A multi-scale study on the effects of littoral forest fragmentation and degradation on birds is therefore a major step forward for bird conservation on the island. Furthermore, prior to this study no known work has been conducted on the avifauna within the threatened littoral forests of eastern Madagascar. My results indicated that (i) the littoral forests contained bird species assemblages that were unique when compared to neighbouring forest habitats, (ii) many forest-dependent bird species were significantly affected by habitat structure and especially proximity to forest edge and (iii) many forest-dependent species were affected by landscape factors such as remnant shape and remnant size. No relationship was found between measures of landscape composition, remnant 'isolation' and bird distribution within littoral forest remnants.

Despite intense publicity, habitat loss still remains a serious threat to biodiversity. Forest destruction is its frontrunner, both in terms of physical habitat under threat and potential for biodiversity loss. In the fragmented landscape of the Taita Hills, SE Kenya, several bird species are facing the threat of extinction from forest loss. They are absent from many of the remnant forest patches and/or are showing negative effects with increasing disturbance. Using a relatively common forest-dependent bird species - the whitestarred robin Pogonocichla stellata - as a model, the current status of this ecosystem was examined, and future patterns predicted in view of the unrelenting destruction. As expected, the robin population in the largest and most intact fragment (c35 ha) was the healthiest, suggesting that this was indeed the best quality habitat patch: it had the highest population density, highest productivity (low nest predation and high juvenile to adult ratio) and lowest turnover rates. Effects of forest deterioration were evident from the fact that the medium-sized patch (c95 ha), which is undergoing severe degradation, was a worse habitat for the robin than the tiny patches (c2-8 ha): it had the lowest population density, lowest productivity (highest nest predation rates and lowest juvenile to adult ratio), and highest turnover rates. The explanation for this is twofold. Besides the smallest patches facing lower levels of habitat loss recently, they also had high levels of dispersal between them. They occasionally operated as a finegrained system with individuals moving between them in the space of a few days. In general, the robin metapopulation is demographically (rate of change, λ = 0.996) and genetically (at migration- and mutation-drift equilibrium) stable at present. The populations in the largest and smallest patches were potential sources providing emigrants that were possibly crucial in sustaining the population in the medium-sized patch (given its low productivity and high turnover rates). Overall, these findings underscore the importance of within-patch processes, both for ensuring persistence of subpopulations and providing dispersers, as well as between-patch processes (chiefly dispersal) for ensuring metapopulation persistence. Thus, by furnishing ample sample sizes that enabled work to be carried out in all fragments throughout this landscape, the model species approach was useful for identifying the need for a two-pronged conservation strategy. First, a need to focus within fragments to reduce habitat loss and degradation, and second, to address among fragment issues relating to land-use and maintaining a forested landscape, in order to enhance connectivity between patches. Finally, based on the mechanisms by which disturbance and fragmentation are affecting bird populations e.g. predator influxes from the surrounding matrix, conservation recommendations for the Taita Hills are offered.

国立情報学研究所で電子化したコンテンツを使用している。

Thesis (Ph.D.)--Tufts University, 2001. / Adviser: J. Michael Reed. Submitted to the Dept. of Biology. Includes bibliographical references (leaves 115-144). Access restricted to members of the Tufts University community. Also available via the World Wide Web;

Thesis (M.S.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on November 1, 2007) Includes bibliographical references.