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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.
531

A Valuation of U.S. Not-For-Profit Summer Camps with a Comparison of Two Members of the Association of Hole in the Wall Camps

Staley, Kristine N. 01 January 2010 (has links)
Despite their prevalence throughout the United States, summer camps are rarely considered as businesses or high-functioning not-for-profit entities. This paper explores the camping industry with a focus on not-for-profit camps. It adapts typical not-for-profit efficiency metrics to camps in order to demonstrate that powerful missions are not always enough to keep not-for-profits in operation. The paper examines two members of the Association of Hole in the Wall Camps which serve children with serious and life-threatening illnesses. Ultimately, this paper is a tool for donors to observe how organizational performance is a crucial factor when donating to organizations with similar mission.
532

Estudi de l'estabilització dels llits fluïditzats sòlios-gas mitjançant l'aplicació d'un camp magnètic

Arnaldos Viger, Josep 03 June 1986 (has links)
La tesi s’inicia fent una presentació del comportament dels llits estabilitzats magnèticament i de les seves aplicacions, així com de les limitacions que tenen degut a les pèrdues de les propietats magnètiques en certes condicions.A continuació, es proposa un model matemàtic dels llits fluïditzats estabilitzats magnèticament, basat en la distribució que segueixen les partícules amb les línies del camp. L’estabilització magnètica també s’ha aplicat a llits fluïditzats amb barreges de partícules magnètiques i no magnètiques. S’ha estudiat el comportament d’aquests sistemes, així com la influència de la fracció màssica de material magnètic en el retard en l’aparició del bombolleig. Els resultats obtinguts mostren que l’estabilització magnètica pot aplicar-se no solament a la fluïdització de partícules magnetitzables sinó també a partícules no magnetitzables, si una certa fracció de material magnètic és present en el llit. Es proposen diferents correlacions per al càlcul de la velocitat de transició en funció de les propietats del sistema gas-sòlid i les condicions d’operació.També s’estudia l’efecte del camp magnètic sobre el comportament tèrmic dels llits fluïditzats de partícules magnètiques escalfats amb una superfície calefactora introduïda dins el llit. S’ha determinat la distribució axial i radial de temperatures en el llit. A partir dels resultats experimentals, s’ha desenvolupat un model que permet el càlcul de la conductivitat tèrmica efectiva del llit. A més, mitjançant l’aplicació de l’analogia de Chilton i Colburn a les dades experimentals obtingudes, s’han proposat diferents correlacions per a l’estimació del coeficient de transferència de calor en llits estabilitzats i semi estabilitzats.Finalment, s’ha estudiat experimentalment, mitjançant l’assecament d’aire humit en llits formats per barreges d’alúmina-acer, la transferència de matèria en llits estabilitzats i semi estabilitzats. S’han emprat dos paràmetres, eficiència del llit i factor de eficiència, per comparar el comportament dels diferents tipus de llits. La precisió del model teòric desenvolupat s’ha provat amb els resultats experimentals obtinguts. Els models corresponents als llits fluïditzats clàssics no presenten un bon ajust amb les dades experimentals; ara bé, quan aquests models són modificats tenint en compte l’efecte del camp magnètic, l’ajust amb les dades és molt millor. / First, in this thesis, the behaviour of the magnetically stabilized fluidized bed is presented, as well as its applications; the limitations due to the loss of magnetic properties in certain conditions are also considered.Later, a mathematical model of the magnetically stabilized fluidized bed, based on the arrangement of particles following field lines is proposed. Magnetic stabilization has also been applied to fluidized beds with mixture of magnetisable and non-magnetisable particles. The behaviour of these systems is studied, as well as the influence of the magnetic material mass fraction on the delay of bubbling. The results obtained show that the magnetic stabilization can be applied not only to the fluidization of magnetisable materials but also to non-magnetisable particles, if a certain fraction of magnetisable material is present. Correlations are proposed to calculate the transition velocity as a function of gas-solid properties and operating conditions.Also, the effect of the magnetic field on the thermal behaviour of a fluidized bed of magnetisable particles with an immersed heating surface has been studied. The temperature distribution inside the bed has been determined, both in the radial and axial directions. A model has been developed which allows calculation of the effective thermal conductivity of the bed from experimental data. In addition, by means of the application of the Chilton and Colburn analogy to the experimental data obtained, different correlations for the estimation of the heat transfer coefficient in stabilized and semi-stabilized beds have been proposed.Finally, the mass transfer in magnetically stabilized and semi-stabilized beds has been studied experimentally using the drying of moist air in beds of alumina-steel mixtures. Two parameters, bed efficiency and efficiency factor have been used to compare the behaviour of the different beds. The accuracy of the theoretical model developed has been tested using the results obtained. The models corresponding to the classical fluidized bed do not agree with experimental data; however, when these models are modified to take into account the effect of magnetic stabilization, the accuracy is much better.
533

Mechanisms controlling the cell body response to axon injury in dorsal root ganglion neurons

Bani Hammad, Rasheed Ahmed 22 June 2010 (has links)
Successful axon regeneration appears to depend on the development of an injury response. Dorsal root ganglion neurons exemplify the necessity of this injury response in a unique way. Peripheral nerve transection leads to development of an injury response and successful regeneration whereas central root transection does neither. The injury response may involve extracellular and intracellular pathways. To investigate the extraneuronal influences, we performed nerve transection of either the central or peripheral axon branches and studied the expression of GAP-43, a key growth associated protein, and the transcription factors ATF3, c-Jun, and STAT3. Our results show that the responses to peripheral versus central nerve transection are fundamentally different. Peripheral but not central nerve transection increases GAP-43, ATF3, and c-Jun expression. STAT3, however, is upregulated as a result of central but not peripheral nerve transection. To investigate potential intracellular signalling pathways, we applied FGF-2, an extracellular mitogen, or an analog of cAMP, an intracellular second messenger to the cut end of the peripheral axon. Our results indicate that FGF-2 and cAMP act as activators of GAP-43 expression. On the other hand, FGF-2 and cAMP act to downregulate the expression of ATF3. FGF-2 upregulates c-Jun and the activated form of STAT3. Paradoxically, the regulation of GAP-43 expression by cAMP or by FGF-2 in vivo shows opposing results from the previously reported in vitro studies. Our present results suggest that the peripheral nerve injury response may be governed by at least three different signalling pathways.
534

L'habitat fortifié pré- et protohistorique en Côte-d'Or : les camps de Myard à Vitteaux et du Châtelet d'Étaules dans le contexte archéologique régional : du Ve millénaire au IVe siècle avant J.-C. /

Nicolardot, Jean-Pierre, Poulain, Thérèse. Putelat, Olivier. January 2003 (has links)
Texte remanié de: Th. doct.--Hist.--Besançon--Université de Franche-Comté, 1993. Titre de soutenance : Les camps de Myard à Vitteaux et du Châtelet d'Étaules, premiers habitats fortifiés de pierre, de bois et de terre en Côte-d'Or, dans leur contexte archéologique : du IVe millénaire au Ve siècle avant J.-C. / En appendice, choix de documents. Bibliogr. p. 240-274. Notes bibliogr. SAE = Société archéologique de l'Est de la France. L'ouvrage porte par erreur : ISSN 0035-0745.
535

Reinhold Heinen (1894-1969) : ein christlicher Politiker, Journalist und Verleger /

Moltmann, Rainer, January 1900 (has links)
Texte légèrement remanié de: Dissertation--Freie Universität Berlin, 2004. Titre de soutenance : Reinhold Heinen : Zentrumpolitiker und Christdemokrat : die politische Biographie eines Verfolgten des nationalsozialismus. / Bibliogr. p. 349-368.
536

Geology of the Campo Bonito area, Oracle, Arizona

Ludden, Raymond Woodbury, 1919- January 1950 (has links)
No description available.
537

Perspectives of northern researchers, residents and educators on science education and outreach in Yukon, Canada

Ross, Frances K P 09 March 2012 (has links)
International Polar Year 2007-2008 renewed interest in and funding for circumpolar research. One unique element of this International Polar Year was the focus on education and outreach initiatives. This study explores outreach stakeholders’ perspectives on conducting science outreach with northern Canadian schools. A total of sixty semi-structured interviews were conducted with northern researchers, residents and educators to determine culturally appropriate and pedagogically suitable methods for educational outreach initiatives in the Canadian north. I examined northern resident and educator experiences with integrating Indigenous and Western ways of knowing, identified factors supporting educational outreach initiatives, and provided recommendations on how to strengthen educational outreach partnerships. Results show that institutional barriers discourage researchers from participating in educational outreach. Northern residents and educators viewed integrative science as an effective method to engage students in Indigenous and Western science, and to encourage collaborative educational outreach partnerships amongst outreach stakeholders.
538

Role of Extracellular-signal Regulated Kinase (ERK) and cAMP Response Element Binding Protein (CREB) in the Incubation of Nicotine Craving

Chang, Shunzhi 21 November 2013 (has links)
Nicotine Addiction is a chronic relapsing disorder. Relapse risk persists despite years of abstinence. Drug-associated cues have been demonstrated to induce craving and provoke relapse. Surprisingly, in human smokers, craving for nicotine increases or “incubates” with longer abstinence durations, a phenomenon that may explain persistent relapse liability. This incubation phenomenon also presents in animals trained to intravenously self-administer nicotine though the underlying mechanisms are unclear. Two proteins, ERK (Extra-cellular signal Regulated Kinase) and CREB (cAMP Response Element Binding protein) play important roles in learning, memory, and numerous aspects of drug addiction. We therefore examined whether changes in these proteins are associated with incubation of craving for nicotine in rats. We found increased nicotine-seeking behaviour after 14 days of abstinence (compared to 1 day) along with elevated ERK and CREB activity in the Accumbens brain region suggesting that these proteins may be involved in the incubation phenomenon.
539

Role of Extracellular-signal Regulated Kinase (ERK) and cAMP Response Element Binding Protein (CREB) in the Incubation of Nicotine Craving

Chang, Shunzhi 21 November 2013 (has links)
Nicotine Addiction is a chronic relapsing disorder. Relapse risk persists despite years of abstinence. Drug-associated cues have been demonstrated to induce craving and provoke relapse. Surprisingly, in human smokers, craving for nicotine increases or “incubates” with longer abstinence durations, a phenomenon that may explain persistent relapse liability. This incubation phenomenon also presents in animals trained to intravenously self-administer nicotine though the underlying mechanisms are unclear. Two proteins, ERK (Extra-cellular signal Regulated Kinase) and CREB (cAMP Response Element Binding protein) play important roles in learning, memory, and numerous aspects of drug addiction. We therefore examined whether changes in these proteins are associated with incubation of craving for nicotine in rats. We found increased nicotine-seeking behaviour after 14 days of abstinence (compared to 1 day) along with elevated ERK and CREB activity in the Accumbens brain region suggesting that these proteins may be involved in the incubation phenomenon.
540

DARPP-32 expression in acquired resistance of breast cancer cells to trastuzumab

Hamel, Sophie. January 2007 (has links)
Amplification of the receptor tyrosine kinase ErbB-2 has been linked to the proliferation of breast cancer cells.1,2 Trastuzumab targets the extracellular domain of ErbB-2, leading to growth inhibition of approximately 15% of the breast cancers with genomic amplification of the ERBB2 gene.3 Clinical studies have demonstrated its efficacy in both early4 and metastatic breast cancers. 5,6 However, many tumors with ERBB2 amplification are not responsive to treatment.7 Moreover, the ones that initially respond, eventually progress and acquire drug resistance.8 An in vitro model for this acquired resistance was established by Chan & al.9 The breast cancer cell line, BT474, containing amplified ERBB2, was grown in the presence of trastuzumab for several months until subclones outgrew. Gene expression profiling was performed on these clones to determine differentially expressed genes between the parental and resistant cells. DARPP-32 (Dopamine and cAMP regulated phosphoprotein of 32kDa) was, by far, the most overexpressed transcript. DARPP-32 is coamplified with ERBB2 on the same amplicon of chromosome 17.10 This protein has been mostly described in neurobiology, but DARPP-32 overexpression was recently reported in gastrointestinal, esophageal, prostate and breast cancer.11 Therefore, we suggest that overexpression of DARPP-32 can cause acquired resistance of breast cancer cells to trastuzumab. The in vitro knockout of DARPP-32, using stable shRNA transfection, abolishes the resistance to trastuzumab in the clones, while overexpression of DARPP-32 in the parental cells results in de novo resistance. Overall, our results suggest that DARPP-32 may be a potential therapeutic target in breast cancer patients who develop acquired trastuzumab resistance.

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