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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.
171

Montuhotep III and his role in the cultural landscape of Thebes

Sunneborn Gudnadottir, Anna January 2016 (has links)
This thesis concerns the cultural landscape in the Theban area during the Middle Kingdom, under the reign of Montuhotep III. What part he played in the connection of the Theban landscape was studied. The outlook point was the only temple that Montuhotep III founded in the Theban area, looking out over contemporary sites. The visibility in the Theban area during the early Middle Kingdom were studied by using Geographic Information System and interpreted by using phenome-nology. The viewshed analysis showed that three out of six contempo-rary sites were visible from Thoth Hill. This information was then used to interpret the choice of location.
172

Deoxygenation-dependent self-association of avian hemoglobins

Rana, Mitra S. J. B. 08 October 2010 (has links)
Cooperative oxygen binding by vertebrate tetrameric hemoglobins (Hbs) has been extensively studied and is relatively well understood. Nonetheless, Hill coefficients greater than four have been reported for adult avian, amphibian, and reptilian red blood cells. Such reports also exist for embryonic red cells from various animals. These results are controversial and not yet convincingly established. Oxygen binding studies on avian Hb D, which is known to undergo deoxygenation-dependent self-association, were carried out to answer this question. The goal was to determine unequivocally whether Hill coefficients greater than four occur. Such high Hill coefficients were observed but only at very high Hb D concentrations. Moreover, the early model of avian deoxy Hb D self-association was found to be incomplete. The model has now been expanded to describe better the observed sedimentation data at high Hb concentrations. The possibility that embryonic deoxy Hbs self-associate was also assessed by sedimentation studies of deoxygenated Hb solutions from a marsupial, the tammar wallaby. The results obtained show unambiguously that these embryonic Hbs self-associate upon deoxygenation. Recent phylogenetic analyses suggest that the avian [alpha superscript D]-globin originated from embryonic [alpha]-globins. This finding suggests that the propensity to self-associate upon deoxygenation is an intrinsic property of tetrameric Hbs with embryonic [alpha]-globins. Furthermore the residues mediating the inter-tetramer interactions in adult avian deoxy Hb D and embryonic deoxy Hbs are likely to be the same. Recombinant globins were expressed in bacteria and protocols for the assembly of avian recombinant tetrameric Hb D developed. Initial measurements by sedimentation were carried out to verify the role of a conserved glutamate residue previously speculated to be involved in inter-tetramer interactions. The present studies provide a framework for future investigations of deoxygenation-dependent Hb self-association. In particular the need to carry out oxygen equilibrium measurements at high Hb concentrations as well as sedimentation studies of the deoxygenated Hb solutions is stressed. / text
173

Analyse du fonctionnement de quelques aménagements de conservation des eaux et du sol : Cas des banquettes en Tunisie Centrale et des lacs collinaires dans la Haute Vallée de Medjerda Analysis of some water and soil conservation measures: contour bench ridge in Central Tunisia and small hill dams in the Medjerda upper stream

Khlifi, Slaheddine 06 July 2007 (has links)
L’objectif du présent travail est l’analyse du fonctionnement des aménagements antiérosifs les plus répandus en Tunisie, les banquettes et les lacs collinaires. L’évaluation des banquettes a été basée sur leur caractérisation, le diagnostic de leur état, leur incidence sur le développement et la croissance de la culture de l’orge et leur impact sur certains paramètres physico-chimiques du sol. La reconstitution des apports hydriques, l’estimation des prélèvements pour l’irrigation et la détermination des apports solides moyens et exceptionnels ont été utilisés comme indicateurs pour l’évaluation des lacs collinaires. L’analyse diachronique a mis en évidence l’importance des cultures annuelles du périmètre aménagé en banquettes et la régression des espaces réservés aux terrains de parcours au cours du temps. Les résultats montrent que certaines banquettes ont été surdimensionnées tel que pour les écartements, les superficies des inter-ouvrages et leur longueur. Le diagnostic de l’état des ouvrages montre qu’une forte proportion des banquettes a été affectée par diverses formes de dégradation qui semblent être en rapport avec l’événement pluvieux exceptionnel de l’hiver 2003. L’évaluation des effets de l’aménagement en banquettes sur la production des céréales montre que la croissance, le développement végétatif et la production de matière sèche de la culture d’orge ont été significativement améliorés pour la zone située à proximité de l’ouvrage en comparaison avec la zone non aménagée. Après plus de trois décennies de la réalisation de l’aménagement, l’accroissement du rendement attribué à la mise en œuvre des banquettes a été évalué à 33% à proximité du bourrelet et à près de 10% en intégrant la superficie de l’ensemble de l’inter-banquette. Par ailleurs, l’aménagement en banquettes permet d’accroître la profondeur du sol, la teneur en matière organique, la capacité de rétention de l’eau, la fraction fine du sol et de réduire le taux de cailloux dans la zone limitrophe des ouvrages. Le taux de carbonates, le pH et la conductivité électrique semblent être non affectés par la mise en œuvre des banquettes. L’évaluation des prélèvements annuels, pour les besoins en eau d’irrigation, en moyenne durant la période de suivi, au niveau des lacs collinaires sur l’oued Fathiza I, l’oued Ras Rmal et l’oued Sned sont plus faibles que les apports effectifs indiquant une sous-utilisation de l’eau. Les apports moyens effectifs représentent entre 36% et 195% des apports estimés selon les ouvrages. Les apports solides moyens initialement estimés pour chacun des trois ouvrages ont été sous évalués se traduisant ainsi par une sédimentation prématurée. Les taux élevés de sédimentation risquent de compromettre la durée de vie des réservoirs. Les pertes de capacité, à la suite des précipitations exceptionnelles de l’hiver 2003, varient de 3,5% à 7,3% de la capacité initiale. Ces taux de sédimentation montrent l’impact des évènements paroxysmiques sur l’érosion au niveau des bassins versants de ces lacs collinaires. La spatialisation de la sédimentation à travers les cuvettes montre que l'essentiel du dépôt solide a lieu à l'amont des cuvettes.
174

Vegetation Assessment to Understand the Effect of Feral Goat Populations on Native Flora Composition

Adkins, Nicholas January 2012 (has links)
A vegetation assessment was conducted to understand the effect of feral goats (Capra hircus) on the vegetation of Isolated Hill Scenic Reserve located in Southern Marlborough. New Zealand forests evolved without the pressure of mammalian herbivores but following human settlement they became subject to intensive browsing following the introduction of exotic mammals. This study focuses on the presence of feral goats. Interest arises from the settlement of other countries and the subsequent liberations of feral goats which are now considered to be responsible for the significant removal of native vegetation as well as playing a dominant role in erosion. Changes in plant communities have occurred with the pressure of goat browsing as well as secondary effects such as habitat degradation The purpose of this research was to investigate the changes in plant species composition since the initial and subsequent research conducted in 1985 and 1994. An analysis of previous work on the diet of multiple introduced ungulate species was also conducted. Previous studies were not limited to only feral goat studies and included other introduced herbivores to provide a broad overview of diets. The New Zealand Forest Service implemented a programme for monitoring the seral forest in Isolated Hill Scenic Reserve using standard Forest Service vegetation quadrants. 32 quadrants were established, including three exclosures, in various locations around the Reserve to allow assessment of feral goat impacts on seral forests (forest whose constituents are of varied age classes). Nine forest service plots, including three exclosures were re-measured and an additional nine plots were measured. Given the progression of vegetation change that has been observed during the course of this study, both analytically and observationally, Isolated Hill Scenic Reserve in its current state, involving the notable presence of feral goats and the vegetation types will continue to diminish in diversity.
175

非齊質變異下尾端風險的衡量

陳俊宏 Unknown Date (has links)
論文名稱:非齊質變異下尾端風險的衡量 校所組別:國立政治大學國際貿易學研究所 指導教授:饒秀華博士 研究生:陳俊宏 關鍵字:風險值、極值理論、厚尾、GPD、GEV、HILL、GARCH模型 論文摘要 台灣加入世界貿易組織(WT0)之後,也相對宣示了國內企業邁向國際化與自由化的向前邁進一步,對於銀行、進、出口商在匯率使用上將會更加的頻繁,因此面對匯率的風險將是無法避免,本研究的目標為每一塊美元兌換台幣的即期匯率資料,以基本的歷史模擬法、變異數-共變異數法,比較極值理論所使用的方法是否有差異存在,而平常使用的非條件模型與條件的GARCH模型比較,條件模型是否能夠比非條件的模型更能正確地估計風險值;另外,條件模型在多日風險值的估計時是否還保有其適用性。 實證結果顯示:整體上而言,在1日風險值估計的模型上,條件模型上的假設確實比非條件的模型較好。在1日的風險值估計下,條件極值理論的使用上比條件變異數-共變異數法或歷史模擬法所估計出來的風險值表現的結果好。在多日的風險值估計下,1日風險值估計模型表現最佳的條件極值理論的模型,卻沒有依然表現的很好,原因是GARCH模型可能無法在時間拉長時,依然做到最好的估計,此時,或許使用非條件的Hill模型以λ<sub>t</sub>的方法來估計風險值,就可以達到不錯的結果。
176

Terminal Pleistocene to early Holocene volcanic eruptions at Zuni Salt Lake, west-central New Mexico, USA

Onken, Jill, Forman, Steven 04 January 2017 (has links)
Zuni Salt Lake (ZSL) is a large maar in the Red Hill-Quemado volcanic field located in west-central New Mexico in the southwestern USA. Stratigraphic analysis of sections in and around the maar, coupled with optically stimulated luminescence (OSL) and accelerator mass spectrometry (AMS) C-14 dating, indicate that ZSL volcanic activity occurred between similar to 13.4 and 9.9 ka and was most likely confined to a <= 500-year interval sometime between similar to 12.3 and 11.0 ka. The basal volcanic unit consists of locally widespread basaltic ash fallout interpreted to represent a violent or wind-aided strombolian eruption tentatively attributed to Cerro Pomo, a scoria cone similar to 10 km south of ZSL. Subsequent eruptions emanated from vents near or within the present-day ZSL maar crater. Strombolian eruptions of multiple spatter and scoria cones produced basaltic lava and scoria lapilli fallout. Next, a phreatomagmatic eruption created the maar crater and surrounding tephra rim and apron. ZSL eruptions ended with strombolian eruptions that formed three scoria cones on the crater floor. The revised age range of ZSL is younger and more precise than the 190-24 ka 2-sigma age range derived from previous argon dating. This implies that other morphologically youthful, argon-dated volcanoes on the southern margin of the Colorado Plateau might be substantially younger than previously reported.
177

A Plantation Family Wardrobe, 1825 - 1835

Lappas, Jennifer 13 December 2010 (has links)
An examination of the Shirley Plantation Collection, Hill Carter, Mary B. Carter, their children, the plantation workers and their wardrobe between 1825 and 1835.
178

Expansion and Exclusion: A Case Study of Gentrification in Church Hill

Parkhurst, Kathryn S 01 January 2016 (has links)
This thesis explores the gentrification process in Church Hill, one of the oldest neighborhoods in Richmond, Virginia. After World War II, Richmond residents knew Church Hill mostly for its crime rate and dilapidated housing. The white, middle-class flight to the suburbs left the remaining residents, mostly African American, to experience decades of disinvestment. Church Hill was considered a neighborhood to avoid for much of the late twentieth century. Yet, Church Hill is currently one of the most desired neighborhoods in Richmond, particularly for young professionals. This thesis seeks to explain the reasons why there has been such a dramatic change in the perception of Church Hill and whether revitalization can occur without causing gentrification. Chapter 1 explores the top-down efforts of the Historic Richmond Foundation, a non-profit organization, and the Model Neighborhood Program, a federal program. Chapter 2 explores revitalization efforts by various non-profits organizations as each tried to work with community members. Chapter 3 explores the reasons why young professionals are moving into Church Hill and the impact of gentrification on the neighborhood.
179

Fighting for Place: The Rhetoric of Preservation in a Gentrifying Urban Neighborhood

Libby, Kelley 01 January 2010 (has links)
This paper looks at how preservationists in Oregon Hill, a gentrifying neighborhood in Richmond, Virginia, appropriated the identity of its working class residents, particularly through claims on a particular cluster of houses. By reframing the meaning of the houses, from homes to sites of historic significance, the preservationists began to “write” themselves into their environment. That is, by engaging the site of the houses both temporally (through narrative) and spatially (by establishing political boundaries), preservationists carved out a space for themselves in the neighborhood. This paper addresses the problems with this process, including the preservationists’ apparent lack of regard for a viable community as anything more than artifact, but also their masking of racial tensions in the neighborhood. Ultimately, though, it shows that preservation is a progressive act, and further, that place, rather than a representation of either progress or preservation, is actually the scene of the dialectic between both.
180

NPR Borečský vrch jako exkurzní cíl výuky botaniky na SŠ / NPR Borečský vrch as a Excursion Destination

Barcalová, Milada January 2013 (has links)
The aim of the present paper is to analyze the curricula for secondary schools in terms of mosses and subsequently prepare a botanical excursion to the NNL Borečský Hill with appropriate didactic materials. Textbooks were compared according to several criteria - the frequency of species of mosses, visual aid, information on the ecology and significance of mosses to ecosystem and human well-being, ideas on field trips and work activities. Topics relating to the planned excursion were selected from the Framework Education Programme. At first, the paper summarizes information about the selected location NNL Borečský Hill which I visited in August 2012 and February 2013. Then an exploration and evaluation of botanical sites follow. There are eight designated sites where the students would perform set tasks. The Chapter: Excursion Proposal contains educational materials created for the excursion - characteristics of selected plant species, characteristic species of bryophytes listed in the field guide, the field guide to bryophytes used on location as well as during laboratory work, route guide for teachers, student worksheets. The materials were tested by students in laboratory work in March 2013 and during the postponed excursion (due to bad weather) in April 2013. The results of the verification are...

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