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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.
61

Properties of BL Lac objects from the 2dF QSO Redshift Survey

Londish, Diana. January 2003 (has links)
Thesis (Ph. D.)--University of Sydney, 2004. / Title from title screen (viewed 14 May 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the School of Physics, Faculty of Science. Degree awarded 2004; thesis submitted 2003. Includes bibliographical references. Also available in print form.
62

Crew rostering problem a random key genetic algorithm with local search /

Rachakonda, Ravi Kanth, January 2008 (has links)
Thesis (M.S.)--Ohio State University, 2008. / Title from first page of PDF file. Includes bibliographical references (p. 47-48).
63

A competitividade das exportações de castanha de caju e melão no Nordeste brasileiro: 1997-2013 / The competitiveness of exports of cashew nuts and melons in northeast Brazil: 1997-2013

Barbosa, Janaina Araujo January 2016 (has links)
BARBOSA, Janaina Araújo. A competitividade das exportações de castanha de caju e melão no Nordeste brasileiro: 1997-2013. 2016. 63 f. :Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrarias, Departamento de Economia Agrícola, Programa de Pós-Graduação em Economia Rural. Fortaleza-CE, 2016 / Submitted by Mário LIMA (mariolima333@gmail.com) on 2016-09-01T18:07:58Z No. of bitstreams: 1 2016_dis_jabarbosa.pdf: 1031310 bytes, checksum: f42f02eb294f5fecdc0487bd2d5b98b4 (MD5) / Approved for entry into archive by Margareth Mesquita (margaret@ufc.br) on 2016-09-02T19:31:25Z (GMT) No. of bitstreams: 1 2016_dis_jabarbosa.pdf: 1031310 bytes, checksum: f42f02eb294f5fecdc0487bd2d5b98b4 (MD5) / Made available in DSpace on 2016-09-02T19:31:25Z (GMT). No. of bitstreams: 1 2016_dis_jabarbosa.pdf: 1031310 bytes, checksum: f42f02eb294f5fecdc0487bd2d5b98b4 (MD5) Previous issue date: 2016 / The development of fruit production in Northeast Brazil faced some challenges and limits in recent years. However, due to the advancement of new technologies and research, managed to advance in some respects, making favorable growth in production of certain crops, which are benefited by the growing international demand for commodities and the attractive price, providing income and employment for exporters, farmers and workers involved in the activity. Thus, this study is essential to analyze the behavior and the main sources of progress or decline in exports of cashew nuts and melon in the Northeast, through commonly known variables as influencers for exports of these products, which are: price of the product in international currency exchange rates, harvested area, average yield in production and the quantity produced by international competitors. The information used in the research were taken from AliceWeb the Ministry of Development System, Industry and Foreign Trade (MDIC), the Municipal Agricultural Production of the Brazilian Institute of Geography and Statistics (IBGE) and IpeaData. To evaluate these influencing factors was made using the Shift Share methodology, using time series covering the period 1997-2013. The methodology that is used in paper proposes innovative in this type of analysis and is the decomposition of the value of exports of both commodities in the effects that hypnotize be definers of progress or setbacks in the value of Northeastern exports of both products. The results in the survey show that the Northeast is losing competitiveness relative to its main competitors (Vietnam and India) in the production and export of cashew nuts, both as regards the expansion area harvested as mainly relative yields, an evidence that the Northeastern production of cashew nuts advances in technological gap in relation to its two main competitors in the international market. Considering the production and export of melon by region, the evidence found in the survey suggest advances Northeastern participation in international melon market, demonstrating greater competitiveness compared to the production of this item in the main international competitors are Spain, Guatemala and the United States of America. / O desenvolvimento da fruticultura no Nordeste brasileiro enfrentou alguns desafios e limites nos últimos anos. Contudo, devido ao avanço de novas tecnologias e pesquisas, conseguiu avançar em alguns aspectos, tornando favorável o crescimento da produção de determinadas culturas, as quais são beneficiadas pela crescente demanda internacional de commodities e pelo preço atrativo, proporcionando renda e emprego para os exportadores, produtores e trabalhadores envolvidos na atividade. Diante disso, este estudo tem como objetivo fundamental analisar o comportamento e as principais fontes de avanço ou retração das exportações da castanha de caju e do melão na região Nordeste, por meio de variáveis comumente conhecidas como influenciadoras para as exportações desses produtos, as quais são: preço do produto em moeda internacional, taxa de câmbio, área colhida, rendimento médio da produção e quantidade produzida pelos concorrentes internacionais. As informações utilizadas na pesquisa foram retiradas do Sistema AliceWeb do Ministério do Desenvolvimento, Indústria e Comércio Exterior (MDIC), da Produção Agrícola Municipal do Instituto Brasileiro de Geografia e Estatística (IBGE) e do IpeaData. Para avaliar esses fatores influenciadores fez-se uso da metodologia Shift Share, com o uso de séries temporais cobrindo o período compreendido entre 1997 e 2013. A metodologia utilizada no trabalho é inovadora neste tipo de análise e consiste na decomposição do valor das exportações destas duas commodities nos efeitos tidos como definidores dos avanços ou retrocessos do valor das exportações nordestinas dos dois produtos. Os resultados encontrados na pesquisa mostraram que a região Nordeste está perdendo competitividade em relação aos seus principais concorrentes (Vietnã e Índia) na produção e exportação de castanha de caju, tanto no que concerne à expansão de área colhida como, principalmente, de rendimento relativo, numa evidência de que a produção nordestina de castanha de caju avança em descompasso tecnológico em relação aos seus dois principais concorrentes no mercado internacional. Considerando a produção e exportação de melão pela região, as evidências encontradas na pesquisa sugerem avanços da participação nordestina no mercado internacional de melão, demonstrando uma maior competitividade frente à produção deste item nos principais concorrentes internacionais, que são Espanha, Guatemala e Estados Unidos da América.
64

Strong Optical Field Ionization of Solids

Ben Taher, Azza January 2018 (has links)
Population transfer from the valence to conduction band in the presence of an intense laser field is explored theoretically in semiconductors and dielectrics. Experiments on intense laser driven dielectrics have revealed population transfer to the conduction band that differs from that seen in semiconductors. Our research explores two aspects of ionization in solids. (i) Current ionization theories neglect coupling between valence and conduction band and therewith the dynamic Stark shift. Our single-particle analysis identifies this as a potential reason for the different ionization behaviour. The dynamic Stark shift increases the bandgap with increasing laser intensities thus suppressing ionization to an extent where virtual population oscillation become dominant. The dynamic Stark shift plays a role dominantly in dielectrics which due to the large bandgap can be exposed to significantly higher laser intensities. (ii) In the presence of laser dressed virtual population of the conduction band, elastic collisions potentially transmute virtual into real population resulting in ionization. This process is explored in context of relaxation time approximation.
65

Synthesis of Homo A-CD Estrogens for Potential Use in Hormone Replacement Therapy

Talbi, Oussama January 2015 (has links)
Hormone replacement therapy (HRT) has been subject to much debate due to concerns that long term use of such treatment of menopause increases the risk of breast and uterine cancer. This is thought to be caused by estradiol (1) binding to the estrogen receptor α (ERα) resulting in increased cell proliferation. Another possible mechanism relates to toxicity of the estrodiol metabolites, which are thought to be genotoxic ortho-quinones. In a previous project, a series of A-CD estrogens (2) were synthesised as non-carcinogenic estradiol agonists where the cis CD ring junction was thought to be the cause of the desirable selectivity for ERβ. In this thesis, homo A-CDs were synthesised (3) with expansion of the D ring thought to increase the selecitivty for ERβ. Relative Binding Affinities (RBA) were determined with selectivity to ERα and ERβ. Most ligands showed decreased selectivity when compared to the original A-CD series. However, compounds carrying the CF3 moiety continued to show very high potency. In addition, novel synthetic routes were employed in the preparation of certain compounds.
66

Patient-specific biomechanical simulation for deep brain stimulation / Simulation biomécanique pour la stimulation cérébrale profonde

Bilger, Alexandre 16 December 2014 (has links)
La stimulation cérébrale profonde est un traitement chirurgical impliquant l'implantation permanante d'électrodes dans le cerveau, afin de stimuler une zone spécifique. La stimulation électrique continue de certaines structures cérébrales traite des symptomes de troubles neurologiques moteurs ou affectifs. Le succès de l'opération repose sur la précision du placement de l'électrode dont le but est de maximiser les bénéfices thérapeutiques, et de minimiser les effets secondaires. Pour cela, une phase de plannification pre-opératoire détermine les coordonnées de la cible à stimuler, ainsi que la trajectoire de l'électrode pour y arriver, à l'aide d'une combinaison d'images médicales du patient et d'outils numériques. Cependant, la déformation intra-opératoire du cerveau, appelée brain shift, peut rendre la plannification invalide. Les contributions de cette thèse s'appuient sur un modèle biomécanique du brain shift qui comprend un modèle de déformation mécanique, ainsi qu'une modélisation de la fuite de liquide cérébro-spinal. Nous présentons un outil pré-opératoire, basé sur notre modèle, afin de fournir au chirurgien une information sur les risques de déformation, qu'il utilise pour sélectionner une trajectoire sécurisée pour le patient, même en cas de brain shift. Dans un deuxième temps, nous proposons une méthode de recalage intra-opératoire basée sur notre modèle biomécanique, afin de calculer la nouvelle position des structures anatomiques. Enfin, grâce à un modèle d'insertion de l'électrode et de son interaction avec les tissus cérébraux, nous reproduisons le protocole opératoire afin de calculer la déflexion de l'électrode due au brain shift. / Deep brain stimulation is a neurosurgical treatment involving the permanent implantation of electrodes in the brain, to stimulate a specific deep structure. Electrical stimulation of some brain structures treat symptoms of motor or affective neurological disorders. The success of the operation relies on the electrode placement precision, which the goal is to maximize the therapeutic outcomes, and minimize the adverse effects. To do that, a pre-operative planning step determine the target coordinates to stimulate, as well as the electrode trajectory to reach it, thanks to a combination of medical images of the patient and numerical tools. However, intra-operative brain deformation, called brain shift, might invalidate the planning. The contributions of this thesis rely on a biomechanical model of brain shift which comprises a mechanical model for deformation, as well as a model of cephalo-spinal fluid leak. We present a pre-operative tool, based on our model, in order to provide to the surgeon an information on the deformation risks, that he could use to select a safe trajectory for the patient, even in the case of brain shift. Moreover, we propose a intra-operative registration method based on our biomechanical model, in order to compute the new location of anatomical structures. Finally, thanks to a model of insertion of the electrode and its interaction with brain tissue, we reproduce the operating protocol in order to compute the electrode curvature due to brain shift.
67

Power nap: Designing for the 24-hour cycle

January 2018 (has links)
One in three Americans, an estimated 83.6 million adults, suffers from sleep deprivation getting less than the recommended seven hours of minimum nightly sleep. Sleep deprivation can lead to increased risk for obesity, diabetes, high blood pressure, stroke, mental distress, coronary heart disease and early death. 1 A prescribed work day and pressure to meet deadlines lead to impaired sleep quality and duration. As the rate of sleep deprivation increases sleep patterns should be reconsidered. Before the 20th century, the light-dark cycle of the earth's rotation dictated daily activity patterns. Modern technology increased the availability of electricity. Light-dark cycles became individually controlled and people gained the ability to stay awake through the night. Social pressures and the rise of technology further contribute to an overall decrease in sleep. The pressure to meet deadlines, participate in social activities and more have led people to impair sleep quality and duration. Operation on individual schedules often results in people cutting back on sleep if they lack flexibility. Innovations in technology advance workplace trends that promote remote communications and flexible schedules, increasing productivity and employee well-being. These trends require an architectural response centered on the needs of the occupants. Through the use of technology and design the everyday work-live environment adjusts to incorporate and encourage sleep based on internal rhythms. This thesis explores how an office building can transform to enable fluidity of activities according to individual 24 hour cycles to create a productive workplace. / 0 / SPK / specialcollections@tulane.edu
68

Measuring gentrification

January 2016 (has links)
0 / SPK / specialcollections@tulane.edu
69

The Effects of the Night Shift on Nursing Staff of an Inpatient Hospice Facility

Horton, Carolyn Dopson 01 January 2015 (has links)
The night shift environment in an inpatient hospice facility is unique in care and relegates challenging situations for the nursing staff. Using the Parse methodology, the purpose of this project was to explore the challenges faced by inpatient hospice facility night shift nursing staff in providing a continuum of care for dying patients and their families. Nine night shift hospice nurses participated in 45-60 minute interviews. The interviews were conducted in a hospice quiet room or a designated place of comfort for the participant, which allowed for dialogical engagement. The interviews were unstructured with open-ended questions about lived experiences. The interpretive phenomenological approach was used to understand positive outcomes and management involvement and developing positive morale. Descriptive coding was used to collect and analyze data. According to study findings, hospice night shift nursing staff were exposed to the stressors of dying patients, their families, a dissatisfied work environment, and their personal life. The core concepts addressed by the participants were feeling isolated and disrespected, staff development, and using coping strategies. Strong relationships through coping mechanisms were developed on the night shift, but the unmet issues of the staff were poorly regarded. The study perpetuates the need for further research in understanding the experiences of hospice night shift nursing staff and the changes needed to eliminate imminent night shift turnover.
70

An automated attentional set-shifting task in HAP, LAP, and alcohol-exposed cHAP mice

Millie, Lauren A. January 2018 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Alcoholics often experience difficulties ceasing drinking, potentially related to excessive behavioral inflexibility that either precedes or results from high alcohol consumption. Components of the Wisconsin Card-Sorting Task (WCST) a type of Attentional Set-Shifting (AttSS) task measuring impairments in behavioral flexibility have been modified to measure similar constructs within animals. Previous work has shown impaired AttSS in abstinent alcoholics and nonalcoholic individuals with a family history of alcoholism, as well as in mice exposed to chronic-intermittent alcohol vapor (Gierski et al., 2013; Hu et al., 2015; Oscar-Berman et al., 2009). The aim of the current study was to assess whether selectively-bred High- vs. Low- Alcohol Preferring (HAP vs LAP) mice display behavioral inflexibility as measured by an operant AttSS task, and furthermore, whether a history of voluntary drinking in cross-bred HAP (cHAP) mice further increases inflexibility. Impairments in the AttSS task are assessed by evaluating the number of trials to reach criterion, as well as the number and types of errors committed during the second experimental phase. In Experiment 1, male and female HAP and LAP mice first learned to press one of two levers signaled by a visual cue, but random with respect to spatial orientation, for a 0.1% saccharin solution reward. The following experimental phase consisted of an egocentric discrimination, such that side (left or right) now signaled correct reinforcement and the location of the visual cue was irrelevant. In Experiment 2, prior to identical operant procedures as Experiment 1, male and female cHAP mice were given free-choice access to 10% alcohol or water for seven weeks. Ethanol-exposed animals drank an average of 29.6 g/kg/day.

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