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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.
111

La construction d'une métropole dominante - Le problème de l'étalement urbain dans la région Damascène (Syrie) / The construction of a dominant metropolis The problem of urban sprawl in the region of Damascus (Syria

Fadel, Tamman 29 November 2016 (has links)
De nos jours, l’étalement urbain est devenu une préoccupation grandissante tant pour les institutions concernées (surtout les collectivités territoriales) que pour les chercheurs qui sont en quête d’analyser les facteurs favorisants ce type d’urbanisation, ainsi que les effets qui en découlent. Ce travail de doctorat s’intéresse à l’étalement urbain dans la région Damascène (en Syrie), un phénomène qui s’accélère au fil des années en menaçant les espaces agricoles de la Ghouta (l’osais de Damas). En tenant compte de la situation de Damas et le rôle qu’elle joue au niveau de la Syrie (comme la capitale d’un pays très centralisé), notre travail vise à comprendre : comment les espaces agricoles de son oasis (la Ghouta) se trouvent menacés par l’étalement urbain, alors que l’Etat semble prendre en considération l’importance vitale de ces espaces ? En s’appuyant sur plusieurs études réalisées en Syrie et en France, des données récoltées à partir des institutions syriennes, ce travail repose sur l’hypothèse suivante : la région damascène, comme le reste des métropoles nationales, est soumise aux conditions générales de l’étalement urbain, ce phénomène s'explique aussi et principalement par d'autres éléments, qualifiés de « spécificités Damascènes ». Donc, au delà d’une simple approche qui s’appuie sur les deux facteurs (démographique et économique), la particularité de cette étude se réside dans d’autres facteurs importants liés au contexte politico-administratif, mais aussi au contexte socioculturel (confessionnel). / Nowdays, Urban sprawl is gaining larger attentions by institutions and researchers who are seeking to analyze its effects and the corresponding contributing factors. This PhD thesis focuses on the urban sprawl phenomenon in the region of Damascus (Syria) that is accelerating with time, and threatening the agricultural spaces of Ghouta (the oasis of Damascus). Taking into account the fact of Damascus being the capital of Syria, a very centralized country, we show in this work how the Ghouta agricultural spaces (that are of great importance as declared by the state) are threatened by this urban sprawl. Based on several studies and on data collected from Syrian local institutions, we show that the Damascus region, like the other national metropolis, is subject to the urban spreading general conditions. Finally, this phenomenon can be also mainly explained by other factors termed "specific Damascenes". Therefore, rather considering a simple approach based only on two factors (demographic and economic), the peculiarity of this PhD lies in considering some additional important factors into consideration when analyzing the urban sprawl phenomenon. Those important factors are those related to the political, administrative and sociocultural context (confessional).
112

Análise química e efeitos letais e sub-letais do óleo essencial de patchouli e sua nanoemulsão em populações de Sithopilus zeamais (Coleoptera: Curculionidae) / Chemical analysis and lethal and sub-lethal patchouli essential oil and its nanoemulsion in populations Sithopilus zeamais (Coleoptera: Curculionidae)

Santos, Álvaro Marcio de Oliveira 27 February 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The maize weevil (Sitophilus zeamais) is one of the stored grain pests of major importance in the world. The indiscriminate use of conventional insecticides has led to the selection of populations of resistant S. zeamais. Although the essential oils (EO) of plants are considered an alternative to conventional insecticides, their range of use due to insect populations with different capacities resistance has not been determined. We examined the toxicity of the EO of Pogostemon cablin and its nanoemulsion on nine populations of S. zeamais from different regions of Brazil. For that were performed bioassays topical application, contact, fumigation, and repellency effects on population growth. Fifteen compounds were identified the EO of P. cablin, and patchoulol was major component (55.04%). The EO of P. cablin showed average activity against the nine populations of S. zeamais when applied topically. The time required to cause 50% mortality of the population was 33.4 hours. The nine populations of S. zeamais responded similarly to EO of P. cablin. The lethal dose to kill 50% of the population resulted in low toxicity index (<2). The population of Viçosa-MG was more susceptible the EO of P. cablin, with LD50 of 9.17 and 8.01 μg mg-1 after 48 and 72 hours exposure respectively. The greater tolerance of EO P. cablin was detected in the population of Sete Lagoas, Minas Gerais, which increased the LD50 of 1.77 and 1.53 times. The concentration the EO of P. cablin required to cause 50% mortality of the population by contact and fumigation ranged from 0.34 to 0.43 μl ml-1 and from 28.6 to 33.5 μl l-1, respectively. Already the nanoemulsion P. cablin showed LC50 ranging from 1.28 to 8.84 μl ml-1 and from 32.7 to 39.5 μl l-1. There was an increase in toxicity by contact and fumigation (LC50) of the nanoemulsion of P. cablin from 48 to 72 hours of exposure. Toxicity (LC50) for contact and fumigation on populations of Viçosa-MG and Sete Lagoas-MG after 48 and 72 hours of exposure to EO P. cablin was in most cases greater than the toxicity caused by nanoemulsion of P. cablin. The EO and the nanoemulsion of P. cablin were LC50 and LC70 repellents in at all times of exposure for the population of Viçosa-MG. The same occurred with the population of Sete Lagoas, Minas Gerais, except for LC50 after 4, 6 and 8 hours of exposure and the LC70 after 24 hours of exposure to nanoemulsion of P. cablin. For the population of Viçosa-MG, there was no difference in repellency caused by EO and nanoemulsion of P. cablin. As for the population of Sete Lagoas, Minas Gerais, EO P. cablin caused greater repellency to this population compared to this oil nanoemulsion. Increasing concentrations of nanoemulsion of P. cablin resulted in reduction and consumption of grains of the two populations. Populations of Viçosa-MG and Sete Lagoas-MG entered decline (ri <0) using concentrations of 50.15 and 67.29 μl kg-1, respectively. / O gorgulho do milho (Sitophilus zeamais) e uma das pragas de graos armazenados de maior importancia no mundo. O uso indiscriminado de inseticidas convencionais tem levado a selecao de populacoes de S. zeamais resistentes. Apesar dos oleos essenciais (OE) de plantas serem considerados uma alternativa ao uso de inseticidas convencionais, sua amplitude de utilizacao frente as populacoes de insetos com capacidades distintas de resistencia ainda nao foi determinada. Neste trabalho analisamos a toxicidade do OE de Pogostemon cablin e da nanoemulsao a base desse OE sobre nove populacoes de S. zeamais provenientes de diferentes regioes do Brasil. Para isso foram realizados bioensaios de aplicacao topica, contato, fumigacao, repelencia e efeitos sobre o crescimento populacional. Foram identificados quinze compostos no OE de P. cablin, sendo o patchoulol o componente majoritario (55,04%). O OE de P. cablin demonstrou atividade inseticida sobre as nove populacoes de S. zeamais quando aplicado topicamente. O tempo necessario para causar 50% de mortalidade das populacoes foi em media 33,4 horas. As nove populacoes de S. zeamais responderam de modo semelhante ao OE de P. cablin. As doses letais para matar 50% das populacoes resultaram em baixas razoes de toxicidade (<2). A populacao de Vicosa-MG foi a mais susceptivel ao OE de P. cablin, com DL50 de 9,17 e 8,01 Êg mg-1 apos 48 e 72 horas de exposicao, respectivamente. A maior tolerancia ao OE de P. cablin foi detectada na populacao de Sete Lagoas-MG, que apresentou aumento na DL50 de 1,77 e 1,53 vezes. A concentracao do OE de P. cablin necessaria para causar 50% de mortalidade das populacoes por contato e fumigacao variou de 0,34 a 0,43 Êl ml-1 e 28,6 a 33,5 Êl l-1, respectivamente. Ja a nanoemulsao de P. cablin apresentou CL50 que variaram de 1,28 a 8,84 Êl ml-1 e 32,7 a 39,5 Êl l-1. Houve aumento da toxicidade por contato e fumigacao (CL50) da nanoemulsao de P. cablin de 48 para 72 horas de exposicao. A toxicidade (CL50) por contato e fumigacao sobre as populacoes de Vicosa-MG e Sete Lagoas-MG apos 48 e 72 horas de exposicao ao OE de P. cablin foi, na maioria das vezes, maior do que a toxicidade causada pela nanoemulsao de P. cablin. O OE e a nanoemulsao de P. cablin foram repelentes nas CL50 e CL70 em todos os tempos de exposicao para a populacao de Vicosa-MG. O mesmo ocorreu com a populacao de Sete Lagoas-MG, excecao para a CL50 apos 4, 6 e 8 horas de exposicao e para a CL70 apos 24 horas de exposicao a nanoemulsao de P. cablin. Para a populacao de Vicosa-MG, nao houve diferenca na repelencia causada pelo OE e nanoemulsao de P. cablin. Ja para a populacao de Sete Lagoas-MG, o OE de P. cablin causou maior repelencia a esta populacao se comparado a nanoemulsao deste OE. Concentracoes crescentes da nanoemulsao de P. cablin resultaram em reducao do ri e do consumo de graos das duas populacoes. As populacoes de Vicosa-MG e Sete Lagoas-MG entraram em declinio (ri<0) a partir das concentracoes de 50,15 e 67,29 Êl kg-1, respectivamente.
113

Linking demography with dispersal and habitat selection for species conservation

Pakanen, V.-M. (Veli-Matti) 29 November 2011 (has links)
Abstract In conservation biology, informed and sound management decisions depend on target specific information about the life history and demography of the endangered populations. I used long-term, individual-based life history data (breeding and capture-recapture data) to examine life-history and demography in order to assess population viability and management. My study systems consist of metapopulations of two endangered, long-distance migratory wader species breeding on Baltic coastal meadows, the Temminck’s stint (Calidris temminckii) and the Southern Dunlin (Calidris alpina schinzii), whose breeding habitats are mainly managed by livestock grazing. Demographic models indicated that both study populations were sinks, which persist through immigration due to low local recruitment insufficient to compensate for adult mortality or emigration. Philopatric Temminck’s stints had higher nest and apparent adult survival compared to immigrants. Consideration of dispersal status in population models resulted in the most realistic estimates of population growth and revealed a low demographic impact of immigrants. Immigrants had low return rates after reproductive failure, suggesting that the difference in apparent survival was partly caused by different breeding dispersal strategies. Thus, management actions improving reproduction, and thus site fidelity, should also influence viability. An artificial nest experiment indicated high trampling rates under recommended stocking rates on managed meadows. This was attributed to similar space use of nesting Dunlin and cattle. Cattle presence did not affect nest predation. Young Dunlin preferred intensively grazed low sward habitat over high sward habitat. Reproductive success was also higher in low sward habitat. However, nests in the preferred habitat had the highest risk of being trampled if not artificially protected. Thus, low sward habitat was found to work as an ecological trap if grazing was started too early in the breeding season. Due to the sink nature of the Dunlin population even small reductions in reproductive success caused by trampling were detrimental to long term viability. The results encourage continuation of the use of cattle grazing as a management tool, but also highlight the need for more detailed consideration of local grazing practices, especially when sketching management plans for endangered species. / Tiivistelmä Uhanalaisten lajien suojelussa tehokkaiden suojelutoimien suunnittelu edellyttää tietoa hoitokohteen elinkierron eri vaiheista ja niiden demografisesta merkityksestä. Käytän tutkimuksessani pitkäaikaisaineistoja (pesintä ja merkintä-takaisinpyynti) kuvatakseni tutkimuslajien demografiaa ja arvioidessani populaatioiden elinkykyä sekä hoitotoimia. Tutkimuskohteinani ovat lapinsirrin ja etelänsuosirrin, kahden uhanalaisen kahlaajan, Perämeren rantaniityillä pesivät metapopulaatiot. Näiden lajien elinympäristöjä hoidetaan pääosin laiduntamalla. Demografinen mallinnus osoitti molempien populaatioiden olevan nielupopulaatioita, joiden säilyminen on tulomuuton varassa sillä poikastuotto ei kompensoi aikuisten kuolleisuutta ja poismuuttoa. Tutkimusalueella syntyneiden ja sinne rekrytoituneiden lapinsirrien pesä- ja aikuissäilyvyydet olivat paremmat kuin tulomuuttajilla. Tämän huomioiminen populaatiomalleissa tuotti realistisimman kasvukertoimen arvion ja osoitti paikallisten rekryyttien olevan tulomuuttajia merkittävämpiä populaation kasvun kannalta. Pesinnässään onnistuneet tulomuuttajat palasivat seuraavina pesimäkausina epäonnistuneita todennäköisemmin. Paikallisilla rekryyteillä vastaavaa eroa ei havaittu. Ilmiö heijastellee tulomuuttajien muuttoalttiutta myöhemminkin ja voi kertoa erilaisista pesimädispersaalistrategioista. Lisääntymismenestyksen parantaminen voisi parantaa elinkykyä myös pienentämällä poismuuttoa. Tekopesäkokeen perusteella pesien tallausriski oli laidunnetuissa ympäristöissä korkea vaikka laidunnuspaine noudatteli hoitosuosituksia. Tämä johtunee ainakin osin laskennallista korkeammasta todellisesta laidunpaineesta, mikä puolestaan johtui lintujen ja karjan yhtäläisestä tilankäytöstä. Rekrytoituvat suosirrit suosivat voimakkaasti laidunnettuja matalakasvuisia niittyjä, joissa poikastuotto oli parempi kuin, laiduntamattomilla niityillä. Toisaalta, tallausriski on voimakkaasti laidunnetuilla niityillä suuri ja jo pienetkin pesätappiot uhkaavat suosirripopulaation elinkykyä. Täten laitumet voivat toimia ns. ekologisina loukkuina, jos laidunnus aloitetaan liian aikaisin suhteessa pesintään. Laidunnus on kuitenkin suositeltava hoitomuoto, sillä se näyttää tuottavan parhaita pesimäympäristöjä etelänsuosirrille. Tulosten mukaan laidunnuksen ajoitusta, laajuutta ja laidunnuspainetta on muokattava kohdekohtaisesti, jotta saavutetaan paras tulos uhanalaisten lajien suojelun kannalta.
114

Bariéry rozvoje v Etiopii: strukturální podmínky a strategie adaptace / Barriers of Development in Ethiopia: Structural Conditions and Strategies for Adaptation

Kuzmič, Michal January 2012 (has links)
The diploma thesis titled Barriers of Development in Ethiopia: Structural Conditions and Strategies for Adaptation is focused on analysis of environmental risk factors and their impact on economic development of Ethiopia. It further evaluates the effectiveness of concrete adaptation measures on both official policy level and community level. The thesis departs from refined version of Jared Diamond's five point framework for analysis of collapse of complex societies. Contemporary scholarly discourse of rapid population growth, deforestation & land degradation and climate variability is formalized into causal schemes and supported by current statistical data. The thesis concludes that adopted measures have had only limited effect on elimination of the respective risk factors. Thus, Ethiopia remains a long-term recipient of foreign humanitarian assistance, without which it would fall into state of economic collapse. To overcome this situation Ethiopia needs to transform its subsistence agricultural production system.
115

Socioeconomic Development In The Southeast Region Of The United States From 1995 - 2000: A Structural Equation Modeling And A Gis Modeling Approach

Eldev-Ochir, Erdenechimeg 15 December 2007 (has links)
This research presented in this study demonstrates that county level population growth, economic growth, and localized social structure are interrelated. An analysis of the spatial distribution of these factors in the Southeast Region of the United States during the period of 1995-2000 also indicates the importance of differences in rural versus urban and coastal versus non-coastal areas as well as the importance of such factors as highways, large cities, and universities in economic, population, and social structure interrelationships. An extensive dataset is used in the analysis as a number of analysis tools including statistical analysis, econometric models, spatial econometric models, structural equation models, and GIS mapping.
116

Demographic trends in the European Union: political and strategic implications

Rasco, Clark Joseph 06 1900 (has links)
Approved for public release, distribution is unlimited / This thesis analyzes adverse demographic trends in the European Union, including sub-replacement birthrates and increasing median ages. It investigates the implications of these trends for the EU's prospects for becoming a stronger and more influential actor in international affairs. Pressures arising from population trends in and near the EU could ultimately affect national and EU cohesion, governmental effectiveness, and social stability. Absent remedial measures, social programs in some EU countries will be unsustainable due to the mounting financial burden of pensions and health care for growing elderly populations. Such financial obligations hinder funding other national programs, including modernized military capabilities. Nationalism and national identity are at issue in immigrant integration and assimilation efforts. The role of population trends with regard to the growing threat of radical Islamic fundamentalism is explored. The thesis concludes with policy recommendations that might be considered to avert the looming economic, social, and security crises that may result from these demographic trends. In short, the security and financial consequences foreshadowed by the current demographic trends of an aging, economically weaker, and socially conflicted European Union could present dramatic implications for the vital national interests of the United States. / Lieutenant, United States Navy
117

A Guideline for Environmental Games (GEG) and a randomized controlled evaluation of a game to increase environmental knowledge related to human population growth

Pisinthpunth, C. January 2015 (has links)
People often have very little knowledge about the impact of unsustainable human population growth on the environment and social well-being especially in developing countries. Therefore, an efficient method should be explored in order to educate, and if possible, to convince the members of the public to realize the environmental and social problems caused by the unsustainable population growth. Digital Game-Based Learning (DGBL) has been highlighted by some studies as an innovative tool for learning enhancement. While only a handful of studies have scientifically evaluated the impact of DGBL on knowledge outcomes, the approach is an attractive tool to increase knowledge and motivate engagement with environmental issues surrounding population growth because of its potential to improve learners’ motivation and engagement thereby compared to traditional learning approaches. Therefore, the three primary research questions for this study are: 1) "Can a single-player digital game be an appropriate and attractive learning application for the players to gain insight about the relationship between the growing human population and the environmental issues?" 2) "How can we design environmental games for the players to gain insights about the relationship between the growing human population and the environmental issues via playing a game?" and 3) "What are the obstacles preventing the players from adapting environmental knowledge obtained from the learning mediums into the real-life?" To inform the development of an efficacious DGBL game to impact learning outcomes, critical reviews of environmental issues related to population growth as well as critical reviews of commercial and serious environmental games in terms of their educational and motivational values were undertaken in this study. The results of these critical reviews informed the development of a Guideline for Environmental Games (or GEG). The GEG was developed by combining the engaging game technology with environmental learning and persuasion theories. The GEG was then used to inform the development of a prototype game called THE GROWTH; a single-player, quiz-based, city-management game targeting young adolescents and adults. Multiple evaluation methods of the game were used to answer the three key research questions mentioned earlier. These methods included: 1) The Randomized Controlled Trial approach (RCT) where the participants were systematically divided into the experimental and the control group respectively and their knowledge scores (quantitative data) compared and analyzed, 2) The participants’ abilities to recall and describe the environmental and well-being issues were collected and analyzed qualitatively using The Content Analysis method (CA) and, 3) The participants’ overall feedback on the learning mediums was collected and analyzed to evaluate the motivational values of THE GROWTH itself. To this end, THE GROWTH was evaluated with 82 Thai-nationality participants (70 males and 12 females). The results showed that participants assigned to play THE GROWTH demonstrated greater environmental and social-well-being knowledge related to population growth (F(1,40) = 43.86, p = .006) compared to the control group participants assigned to a non-interactive reading activity (consistent with material presented in THE GROWTH). Furthermore, participants who played THE GROWTH recalled on average more content presented in the game when compared to participants who were presented with similar content in the reading material (t (59) = 3.35, p = .001). In terms of level of engagement, the study suggested that participants assigned to the game were more engaging with their learning medium on average when compared to participants assigned to the non-interactive reading activity. This is evidenced by the longer time participants spent on the task, the activity observed from participants’ recorded gameplay, and their positive responses in the survey. The semi-structured interviews used in this study highlighted the participants’ attitudes towards the environmental, social, and technological issues. Although the participants’ perceived behavioural intention towards the environmental commitments were not statistically differed between the two study group, their responses still provide some evidences that leaps may occur from the learning mediums to the real-world context. Furthermore, these responses can be valuable evidences for the policy makers and for the future development of environmental serious games. Overall, the results suggested that digital environmental games such as THE GROWTH might be an effective and motivational tool in promote the learning about sustainable population size, the environment, and the social well-being. The game’s ability to convince the participants to change towards sustainable lifestyles, however, might be subjected to the future research and other real-world circumstances such as the governmental and public supports. In summary, the research in this thesis makes the following contributions to knowledge: • The Guideline for Environmental Games (GEG) contributes to knowledge about making theoretically-based environmental games. It has particular significance because the guideline was validated by demonstrating learning improvements in a systematic randomized controlled trial. • The use of Multi-Strategy Study Design where multiple systematic evaluation methods were used in conjunction to provide conclusive findings about the efficacy of DGBL to impact outcomes. • THE GROWTH itself is a contribution to applied research as an example of an effective DGBL learning tool.
118

Aplikace matematických znalostí při výuce biologie

STUDENÁ, Lucie January 2018 (has links)
The Theses deals with applications of mathematical knowledge in teaching biology and it is divided into four chapters. Each chapter is dedicated to another application: 1. Application of conditional probability in medical diagnostics, 2. Application of exponential function in population ecology, 3. Application of logic functions in mathematical modelation of neuron and 4. Aplication of binomial theorem and binomial distribution in genetics. Each application contains solved problems, a worksheet for students and a solution for each worksheet. Two application (1. and 2.) have been tested in teaching and as an assessment of my lessons students filled questionnaires. Results of these questionnaires are processed in the end of these chapters. This Thesis can be used in teaching or self-studying.
119

Livable Communities

Vice President Research, Office of the January 2009 (has links)
What makes a community sustainable? Is it the effective management of local environmental resources? Or meeting the social, economic and health needs of its population? For the five UBC researchers in the following pages, the answer is unequivocally both. From tackling water scarcity to environmental health and planning, these researchers are individually working to ensure local communities are equipped with the necessary knowledge to remain sustainable for generations to come.
120

Dopady regulace porodnosti na růst čínské ekonomiky / The Implications of Family Planning Policies on the Growth of Chinese Economy

Skořepová, Kateřina January 2013 (has links)
Apart from rapid economic growth, China has also experienced significant demographic changes over the past few decades. The People's Republic of China's family planning policies led to a sharp drop in the fertility rate. This MS Thesis aims to assess the possible consequences of the family planning policies on future growth of Chinese economy. The theoretical part defines population policy, assess the connections between population growth and economic growth and deals with the development of population theory over the years. The analytical part describes the family planning policy in China, its principles and instruments. Next it identifies the possible consequences of the demographic changes caused by the drop in fertility rate. The last part of the thesis focuses on two economically most severe consequences - population ageing and shrinking working age population - and evaluates its implications on future growth of Chinese economy.

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