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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Vivre la révolution de 2011 à distance : sociologie des migrations égyptiennes en France / Living the 2011 revolution from abroad : sociology of Egyptian migrations in France

Lamblin, Célia 27 November 2018 (has links)
Cette thèse initiée en octobre 2013 s’attache à comprendre en quoi les événements politiques survenus en Égypte entre 2011 et 2016 ont pu peser sur les trajectoires individuelles et les registres de l'action collective des Égyptiens installés en France. À partir d'une sociologie des migrations égyptiennes en France, ce travail ambitionne plus largement de comprendre comment un événement peut influencer les trajectoires individuelles de ceux qui n'en sont pas directement témoins. Inscrit à la croisée d'une sociologie des migrations et d'une sociologie de l'action collective, ce travail interroge le poids et les rôles des mobilisations à distance. L'enquête de terrain multisituée (durant laquelle des entretiens et des observations ont été menés dans les villes de Paris, de Marseille, mais aussi dans plusieurs localités égyptiennes), inscrit ce travail dans la lignée des travaux portant sur les formes de politisation par l'événement et contribue aux études sur la participation politique à distance. / Initiated in October 2013, this thesis aims at understanding how the 2011 and 2016 political events that occurred in Egypt may have weighed on both individual trajectories and collective action registers of the Egyptians living in France, more specifically in Paris and Marseilles. Starting from a sociology of Egyptian migrations in France, this work more broadly aims at understanding how an event can influence the individual trajectories of those who are not first-hand witnesses. At the crossroads of a sociology of migration and a sociology of collective action, this work questions the weight and roles of remote mobilizations. The multi-site field survey (during which interviews and observations were conducted in Paris, Marseilles, and several Egyptian localities), inscribes this work in line with works on forms of politicization by the event and contributes to studies on long distance political participation.
152

Seed mobility and connectivity in changing rural landscapes

Auffret, Alistair G. January 2013 (has links)
The success or failure of many organisms to respond to the challenges of habitat destruction and a warming climate lies in the ability of plant species to disperse between isolated habitats or to migrate to new ranges. European semi-natural grasslands represent one of the world's most species-rich habitats at small scales, but agricultural intensification during the 20th century has meant that many plant species are left only on small fragments of former habitat. It is important that these plants can disperse, both for the maintenance of existing populations, and for the colonisation of target species to restored grasslands. This thesis investigates the ecological, geographical and historical influences on seed dispersal and connectivity in semi-natural grasslands, and the mobility of plants through time and space. Seed dispersal by human activity has played a large role in the build-up of plant communities in rural landscapes, but patterns have shifted. Livestock are the most traditional, and probably the most capable seed dispersal vector in the landscape, but other dispersal methods may also be effective. Motor vehicles disperse seeds with similar traits to those dispersed by livestock, while 39% of valuable grasslands in southern Sweden are connected by the road network. Humans are found to disperse around one-third of available grassland species, including several protected and red-listed species, indicating that humans may have been valuable seed dispersers in the past when rural populations were larger. Past activities can also affect seed mobility in time through the seed bank, as seeds of grassland plant species are shown to remain in the soil even after the grassland had been abandoned. Today however, low seed rain in intensively grazed semi-natural grasslands indicates that seed production may be a limiting factor in allowing seeds to be dispersed in space through the landscape. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Accepted. Paper 4: In press. Paper 5: Manuscript.</p>
153

A Discrete-Continuous Modeling Framework for Long-Distance, Leisure Travel Demand Analysis

Van Nostrand, Caleb 01 January 2011 (has links)
This study contributes to the literature on national long-distance travel demand modeling by providing an analysis of households' annual destination choices and time allocation patterns for long-distance leisure travel purposes. An annual vacation destination choice and time allocation model is formulated to simultaneously predict the different destinations that a household visits and the time it spends on each of these visited destinations, in a year. The model takes the form of a Multiple Discrete-Continuous Extreme Value (MDCEV) structure (Bhat, 2005; Bhat, 2008). The model assumes that households allocate their annual vacation time to visit one or more destinations in a year to maximize the utility derived from their choices. The model framework accommodates variety-seeking in households' vacation destination choices in that households can potentially visit a variety of destinations rather than spending all of their annual vacation time for visiting a single destination. At the same time, the model accommodates corner solutions to recognize that households may not necessarily visit all available destinations. An annual vacation time budget is also considered to recognize that households may operate under time budget constraints. Further, the paper proposes a variant of the MDCEV model that avoids the prediction of unrealistically small amounts of time allocation to the chosen alternatives. To do so, the continuously non-linear utility functional form in the MDCEV framework is replaced with a combination of a linear and non-linear form. The empirical data for this analysis comes from the 1995 American Travel Survey Data, with the U.S. divided into 210 alternative destinations. The empirical analysis provides important insights into the determinants of households' leisure destination choice and time allocation patterns. An appealing feature of the proposed model is its applicability in a national, long-distance leisure travel demand model system. The annual destination choices and time allocations predicted by this model can be used for subsequent analysis of the number of trips made (in a year) to each destination and the travel choices for each trip. The outputs from such a national travel modeling framework can be used to obtain national-level Origin-Destination demand tables for long-distance leisure travel.
154

THE IMPACT OF VIDEO CHATTING ON IDEALIZATION AND DISILLUSIONMENT FOR LONG DISTANCE DATING COUPLES

Kusisto, Laura 01 January 2015 (has links)
Previous research indicates a high rate of long distance relationships, especially among young adults. Yet, research in this area is lacking, particularly regarding the role of video chatting. Through the lens of the media richness theory and the hyperpersonal model, this qualitative study explores how video chatting impacts idealization and disillusionment in young adults’ long distance dating relationships. Data was collected through semi-structured interviews with both partners of six heterosexual couples. Data was analyzed using the constant comparative approach and following the basic framework of open, axial, and selective coding used in grounded theory research. Results indicate that video chatting helps partners feel close to one another, though partners must still manage the differences between feeling close and actually being close. Couples use idealization and uncertainty management to reduce disillusionment, and couples who anticipate changes manage those changes more successfully. These findings suggest that video chatting mimics in-person communication more accurately than any other technology, though it cannot replace true geographic proximity. Nonetheless, video chatting appears to help minimize disillusionment by promoting healthy idealization for couples who use it throughout their long distance dating relationship.
155

The effect of ultradistance running on premenopausal women of different ethnic groups.

McGregor, Avril. January 2005 (has links)
No abstract available. / Thesis (M.Med.Sc.)-University of KwaZulu-Natal, Durban, 2005.
156

Långdistanslöpning och artros : En systematisk litteraturstudie / Long distance running and osteoarthritis : A systematic review

de Flon, Peter January 2014 (has links)
Sammanfattning   Syfte och frågeställningar Syftet med denna studie var att sammanställa kvalitet på och resultat av studier som undersökt om långdistanslöpning ger artros i höft-, knä- eller fotleder. Finns det vetenskaplig evidens för att långdistanslöpning ger artros i höft-, knä- eller fotleder? Vilka styrkor och svagheter har de studier som försökt utröna om samband finns mellan långdistanslöpning och artros i höft-, knä- eller fotleder?   Metod Sökning av litteratur utfördes i PubMed, CINAHL, Cochrane Library och PEDro. Detta resulterade i att tio artiklar inkluderades för närmare granskning och sammanställning. Utifrån artiklarnas sammantagna bevisvärde poängsattes och graderades artiklarna efter evidensnivå enligt Statens Beredning för medicinsk Utvärderings (SBU) granskningsmallar för kohortstudier med kontrollgrupper.   Resultat Endast en av tio studier visar ett positivt samband mellan långdistanslöpning och artros i höft-, knä- eller fotleder, i detta fall höftledsartros. Studierna har ingen tydlig och gemensam definition över vad långdistanslöpning är. De granskade studierna använder sig av olika mätmetoder för att bedöma leddegenerationen, både av självrapportering och av olika diagnostiska kriterier för artros. Alla studier har inslag av selektionsbias.   Slutsats En indikation på att det inte finns ett vetenskapligt stöd för att långdistanslöpning ger höft-, knä- eller fotledsartros hos människor. Studierna har brister i hantering av confounders och selektionsbias och bedöms vara av låg eller medelhög kvalitet. / Abstract   Aim The purpose of this study was to compile the quality and results of studies that examined if long-distance running gives osteoarthritis of the hip, knee or ankle joints. Is there scientific evidence that long-distance running gives osteoarthritis of the hip, knee or ankle? What strengths and weaknesses of the studies attempted to determine if the link between long-distance running and osteoarthritis of the hip, knee or ankle joints.   Method Search of the literature was performed in PubMed, CINAHL, Cochrane Library, and PEDro. This resulted in ten articles that were included for further review and compilation. Based on the articles combined probative value was scored and graded articles for level of evidence according to the National Council on Technology Evaluation (SBU) examination templates for cohort studies with control groups.   Results Only one of the ten studies showed a positive association between long distance running and osteoarthritis of the hip, knee or ankle joints, in this case hip joint. The studies have not a clear and common definition of what long-distance running is. The studies reviewed use different metrics to assess joint degeneration, both by self-report and of different diagnostic criteria for osteoarthritis. All studies have an element of selection bias.   Conclusion An indication that there is no scientific evidence that long-distance running gives hip, knee or ankle osteoarthritis in humans. The studies were inadequate handling of confounders and selection bias and judged to be of low or medium quality.
157

Dispersal of bryophytes across landscapes

Lönnell, Niklas January 2014 (has links)
Dispersal, especially long-distance dispersal, is an important component in many disciplines within biology. Many species are passively dispersed by wind, not least spore-dispersed organisms. In this thesis I investigated the dispersal capacity of bryophytes by studying the colonization patterns from local scales (100 m) to landscape scales (20 km). The dispersal distances were measured from a known source (up to 600 m away) or inferred from a connectivity measure (1–20 km). I introduced acidic clay to measure the colonization rates over one season of a pioneer moss, Discelium nudum (I–III). I also investigated which vascular plants and bryophytes that had colonized limed mires approximately 20–30 years after the first disturbance (IV). Discelium effectively colonized new disturbed substrates over one season. Most spores were deposited up to 50 meters from a source but the relationship between local colonization rates and connectivity increased with distance up to 20 km (I–III). Also calcicolous wetland bryophyte species were good colonizers over similar distances, while vascular plants in the same environment colonized less frequently. Common bryophytes that produce spores frequently were more effective colonizers, while no effect of spore size was detected (IV). A mechanistic model that take into account meteorological parameters to simulate the trajectories for spores of Discelium nudum fitted rather well to the observed colonization pattern, especially if spore release thresholds in wind variation and humidity were accounted for (III). This thesis conclude that bryophytes in open habitats can disperse effectively across landscapes given that the regional spore source is large enough (i.e. are common in the region and produce spores abundantly). For spore-dispersed organisms in open landscapes I suggest that it is often the colonization phase and not the transport that is the main bottle-neck for maintaining populations across landscapes. / <p>At the time of the doctoral defence the following papesr were unpublished and had  a status as follows: Paper 2: Epubl ahead of print; Paper 3: Manuscript; Paper 4: Manuscript</p>
158

On the road : Social aspects of commuting long distances to work / På väg : Sociala aspekter av långväga pendling

Sandow, Erika January 2011 (has links)
With its point of departure of increasing numbers of people being engaged in commuting, the aim of this thesis is to reveal prerequisites for and consequences of long-distance commuting in Sweden for the individual and his or her partner. Special attention has been given to prerequisites for long-distance commuting in sparsely populated areas, and to social consequences related to long-distance commuting in terms of gender differences in commuting patterns, earnings and separation. The thesis is based on four empirical studies, presented in different papers. Two studies draw on individual longitudinal register data on all Swedish long-distance commuters living with a partner. The other two focus on commuting behaviour in sparsely populated areas, one based on individual register data and the other on a survey. Long-distance commuting (&gt;30 kilometres) has become an increasingly common mobility strategy among Swedish workers and their households. Results from the thesis show that 11 percent of Swedish workers are long-distance commuters and about half of them live in a relationship. Among these couples many are families with children, indicating the importance of social ties in households’ decisions on where to work and live. Most long-distance commuters are men, and it is also likely that long-distance commuters have a high education level and are employed in the private sector. For the majority, long-distance commuting gives higher earnings; however, men benefit economically more than women do. As long-distance commuting reduces available family time, the non-commuting spouse often takes on a larger share of household commitments. The thesis shows that men’s long-distance commuting may therefore serve to reproduce and reinforce traditional gender roles on the labour market and within households. On the other hand, women’s long-distance commuting can lead to more equalitarian relationships on the labour market and within households. For the majority of couples it seems as if long-distance commuting becomes more than a temporary mobility strategy, while for some couples it does not work out very well. Separation rates are found to be higher among long-distance commuters compared to other couples; especially the first years of commuting seem to be the most challenging. It is suggested that coping strategies are important to make the consequences of long-distance commuting easier to handle and adjust to in the daily life puzzle. For those unable to handle these consequences, long-distance commuting is not a sustainable mobility strategy and can even end a relationship. The extent of long-distance commuting is low in sparsely populated areas, and those who do long-distance commute are mainly men. Most people work and live within the same locality and do not accept longer commuting times than do those in densely populated areas. In this thesis it is argued that facilitating car commuting in the more sparsely populated areas of Sweden can be more economically and socially sustainable, for the individual commuters as well as for society, than encouraging commuting by public transportation.
159

Heads and adjuncts : an experimental study of subextraction from participials and coordination in English, German and Norwegian

Brown, Jessica M. M. January 2017 (has links)
In recent years, attempts to simplify the grammatical mechanisms used in syntax have led to proposals to reduce the relationships between elements in a sentence to relations between heads and complements, doing away with free adjunction. For the analysis of modifying relations one consequence has been the rise of analyses that use the properties of selecting heads to stipulate unexpected syntactic behaviour, such as the use of light verbs to derive transparency in complex verb constructions. This thesis shows that such accounts are empirically inadequate and argues that the relationship between heads and adjuncts provides a more empirically-satisfactory model of modifying relations, such as complex verb constructions, than one restricted to the selection relation between heads and complements in the syntax. In support of the adjunct relation, I show how a modular approach to adjuncts in which the position of adjunction is licensed in the semantics and long-distance dependencies are licensed in the syntax can provide a more unified account of subextraction from two separate types of island configurations, viz. asymmetric subextraction from coordination and subextraction from participial adjuncts, either than analyses involving complementation in the syntax (Borgonovo and Neeleman, 2000; Fabregas and Jiménez-Fernández, 2016; Wiklund, 2007), or hybrid analyses mixing processing filters with syntactic licensing of long-distance dependencies (Truswell, 2009, 2011). The first part of the thesis shows that Chomsky’s (2000; 2001) phase theory gives rise to blackholes in the specifier positions of phases from which movement cannot take place. I provide a theoretical account in terms of feature-licensing, where blackholes are formed by the impossibility of licensing at least one unlicensed feature on a phase head, and show how this account derives the distinction between canonical adjuncts from which subextraction is not permitted and subextraction from single event constructions in which subextraction is permitted. The section speculatively concludes with a demonstration of how blackholes might provide a unified analysis of islandhood in general. The second part of the thesis concentrates on the empirical phenomenon of subextraction from coordination and participial adjuncts. I report the results of a series of judgement experiments run in parallel across two sets of constructions, coordination and participial adjuncts, in three languages, English, German and Norwegian. The aim was to test whether acceptability of subextraction from within coordination and participial adjuncts varied depending on the aspectual or grammatical type of matrix predicate. The results show that acceptability of subextraction does depend on the type of matrix predicate. The crucial factor is intransitivity, partially confirming the bias towards unaccusatives in subextraction from participial adjuncts observed informally in Borgonovo and Neeleman (2000); Fabregas and Jiménez-Fernández (2016); Truswell (2011) whilst providing evidence against theoretical accounts that rely primarily on unaccusativity (Borgonovo and Neeleman, 2000; Fabregas and Jiménez-Fernández, 2016), primarily on aspectual distinctions (Truswell, 2007b) or primarily on agentivity (Truswell, 2009, 2011). Interestingly, the hierarchy in acceptability between the four types of matrix predicates stays constant across all three languages, despite both pseudocoordination and subextraction from within participials being ungrammatical in German.
160

The biogeographic affinities of the Sri Lankan flora

Kumarage, Lakmini Darshika January 2017 (has links)
The island of Sri Lanka’s exceptional biodiversity and enigmatic biogeography begs investigation, as the island is key in understanding the evolution of the Asian tropical flora. Since the Jurassic, Sri Lanka has been subjected to remarkable tectonic changes, thus its flora could have been influenced by that of a number of nearby landmasses, as well giving Sri Lanka the potential to have played a wider role in the assemblage of floras elsewhere. Firstly, as Sri Lanka originated as a fragment of the supercontinent Gondwana, part of its flora may contain Gondwanan relict lineages. There is also the potential for immigration from Laurasia after the Deccan Plate collided with it 45-50 Mya. Further, Sri Lanka may harbour floristic elements from nearby land masses such as Africa and Southeast Asia as a result of long distance dispersals, and in situ speciation has the potential to have played an important role in enhancing the endemic Sri Lankan flora. I tested the relative contributions of the above hypotheses for the possible origins of the Sri Lankan flora using three representative families, Begoniaceae, Sapotaceae and Zingiberaceae. These families represent both herbaceous and woody elements, and have high diversity across the tropics. Dated molecular phylogenies were constructed for each family. I used recent analytical developments in geographic range evolution modelling and ancestral area reconstruction, incorporating a parameter J to test for founder event speciation. A fine scale area coding was used in order to obtain a better picture of the biogeography of continental Asia. Amongst all the models compared, a dispersal-extinction cladogenesis model incorporating founder event speciation proved to be the best fit for the data for all three families. The dates of origin for Sri Lankan lineages considerably post-date the Gondwanan break up, instead suggesting a geologically more recent entry followed by diversification of endemics within the island. The majority of Sri Lankan lineages have an origin in the Sunda Shelf (53%). Persistence of warm temperate and perhumid climate conditions in southwestern Sri Lanka resembling those of Peninsular Malaysia and Sumatra could have facilitated suitable habitats for these massive dispersals from the Sunda Shelf region. Some trans-oceanic long distance dispersals from Africa (11%) are also evidenced, again these are too young to accept a hypothesis of dispersal during the Deccan Plate’s migration close to the African coast during the late Cretaceous, but occurred later during the Miocene. Further, some lineages of Laurasian origin (20%) are evidenced in the Zingiberaceae with ancestral areas of China and Indochina, which is congruent with a post collision invasion. Among the families tested, dispersals have occurred stochastically, one during the Eocene, six during the Oligocene, seven during the Miocene, two during the Pliocene and one during the Pleistocene. The highest number of dispersals occurred during the Miocene when a warm climate was prevailing during the Miocene thermal maximum. My results confirm that in situ speciation is an important contributor to the Sri Lankan flora. More rapid radiation of endemics has occurred during Pliocene-Pleistocene; two endemics in Begoniaceae, ten endemics in Sapotaceae and ten endemics in Zingiberaceae have evolved in situ during this period. Sri Lanka will have been subjected to expansion and contraction of climatic and vegetation zones within the island during glacial and interglacial periods, potentially resulting in allopatric speciation. As a conclusion, long distance dispersals have played a prominent role in the evolution of the Sri Lankan flora. The young ages challenge the vicariant paradigm for the origin and current disjunct distributions of the world’s tropical lineages and provide strong evidence for a youthful tropics at the species level. The thesis contains six chapters; first two are introductory chapters, then there are three analytical chapters, one for each family, and finally a summary chapter is provided. Each analytical chapter is written as a stand-alone scientific publication, thus there is some repetition of relevant content in each.

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