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O complexo de rutênio doador de óxido nítrico trans-[ru(NO)Cl(cyclam)](PF6)2 inibe a proliferação e migração de células musculares lisas vasculares induzida pelo fator de crescimento derivado de plaquetas / The ruthenium complex nitric oxide donor trans -[ru(NO)Cl(cyclam)](PF6)2 inhibits vascular smooth muscle cell proliferation and migration induced by platelet derived growth factorOliveira, Mariana Gonçalves de, 1987- 08 May 2013 (has links)
Orientador: Marta Helena Krieger / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-23T15:25:30Z (GMT). No. of bitstreams: 1
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Previous issue date: 2013 / Resumo: O óxido nítrico (NO) é um multifuncional agente biológico que nas últimas décadas tem sido alvo de uma infinidade de estudos e constitui hoje um dos mais importantes mediadores de processos intra e extracelulares. Diversos estudos demonstram sua capacidade de prevenção da ativação e adesão plaquetária ou leucocitária e inibição da proliferação e migração de células musculares lisas vasculares (VSMCs), entretanto, em condições de baixa disponibilidade do NO esses processos são prejudicados. Atualmente há o grande interesse no desenvolvimento de compostos capazes de liberar NO de forma modulada e estável, e, nesse sentido, os complexos nitrosilos de rutênio têm se destacado por suas características excepcionais. É amplamente reconhecido que a modulação fenotípica de VSMCs tem papel crítico na progressão de diversas doenças vasculares proeminentes. Sabe-se que o fator de crescimento derivado de plaquetas (PDGF-BB) é um dos principais estimulantes desse processo. Este estudo se propôs a caracterizar os efeitos inibitórios do complexo de rutênio trans-[Ru(NO)Cl(cyclam)](PF6)2, nomeado Ru(cyclam)NO, na modulação fenotípica, resposta proliferativa e migratória de VSMCs induzidas por PDGF-BB. VSMCs foram obtidas por técnica de cultura primária. A citotoxicidade do complexo, na faixa de concentração de 100 ?M a 1500 ?M, foi determinada em ensaios de redução do MTT e incorporação neutral red (NR), e comparadas a do nitroprussiato de sódio (SNP). A concentração 100 ?M foi definida para os demais protocolos experimentais. Western blotting, ensaios transwell e wound healing, e incorporação de timidina triciada foram utilizados para determinação da modulação fenotípica, migração e proliferação celular, respectivamente, e níveis de nitrato no meio foram determinados por quimiluminescência para avaliação do perfil de liberação de NO. O complexo demonstrou baixa citotoxicidade, mesmo na maior concentração e após 48 horas de exposição, reduzindo ao máximo em 30% a porcentagem de células viáveis em ambos os ensaios, demonstrando ser menos tóxico que o SNP. Níveis de nitrato no meio atigiram a concentração máxima após 30 minutos (11 ?M ± 4,8), de maneira mais lenta em relação ao SNP, cuja concentração máxima foi após 5 minutos (13 ?M ± 3,7). A proliferação das VSMCs induzida por PDGF-BB foi inibida, reduzindo à metade a radioatividade incorporada, bem como a expressão do marcador de proliferação PCNA. Observou-se redução de 45% na migração induzida por PDGF-BB nos ensaios transwell, e no wound-healing, embora qualitativo, a redução é notável. A modulação fenotípica da VSMC foi observada pela redução em 60% da expressão da proteína alfa-actina, característica do fenótipo maduro, e foi quase totalmente prevenida pelo tratamento com o complexo. Tal prevenção pode ser mediada pelo fator de transcrição ELK-1, que favorece a expressão de genes de diferenciação, e cuja fosforilação foi estimulada pelo PDGF-BB, porém inibida em quase 50% pelo pré-tratamento com Ru(cyclam)NO. As respostas observadas nos tratamentos com Ru(cyclam)NO foram promissoras, e, embora seu mecanismo de ação x ainda não esteja completamente esclarecido, este complexo demonstrou atividade biológica singular, e sua aplicação em condições clínicas onde há descontrole de processos de proliferação e migração de VSMCs, como a reestenose, apresenta-se como uma proposta interessante / Abstract: Nitric oxide (NO) is a multifuctional biological agent that in the recent decades has been the subject of a plethora of studies and today is one of the most important intracellular and extracellular processes mediators. Several studies have demonstrated its ability to prevent leukocyte or platelet adhesion and activation, and inhibition of vascular smooth muscle cells (VSMCs) proliferation and migration. However, low availability of NO conditions determines impairement of these processes. There is a keen interest in the development of compounds capable of releasing NO modulated so stable, and the nitrosyl ruthenium complexes have gained prominence for its exceptional features. It is widely recognized that the phenotypic modulation of VSMCs, and its uncontrolled proliferation and migration, plays a critical role in the progression of several prominent vascular diseases. It is known that the platelet-derived growth factor (PDGF) is a primary stimulant of the process. This study aimed to determine the inhibitory effects of the ruthenium complex NO donor trans-[Ru(NO)Cl(cyclam)](PF6)2, named Ru(cyclam)NO, in the phenotypic switching, on migratory and proliferative responses of VSMCs induced by PDGF-BB, and its biological response. VSMCs were obtained from primary culture methodology. The complex cytotoxicity were determined by MTT reduction and incorporation of neutral red (NR) assays, in the range of concentration from 100 ?M to 1500 ?M, and compared to sodium nitroprusside (SNP). For the following experimental protocols the concentration of the 100 ?M was set. Western blotting, transwell and wound healing assays, and incorporation of tritiated thymidine were used for determination of phenotypic switching, cell migration and proliferation, respectively. Evaluation of the NO profile release was determined as nitrate levels in the culture medium by chemiluminescence. The complex Ru(cyclam)NO showed low cytotoxicity even at the highest concentration evaluated and after 48 hours of exposition, reducing only 30% the percentage of viable cells in both trials, showing be less toxic than the SNP. Medium nitrate levels exibhited the highest concentration after 30 min (11 ?M ± 4.8), slower when compared to SNP, which reached the maximum concentration after 5 minutes (13 ?M ± 3.7). The proliferation of VSMCs induced by PDGF-BB was inhibited by half of the radioactivity incorporated counting, as well as the reduction on the expression of the proliferation marker PCNA. Observed a reduction by 45% in the migration induced by PDGF-BB determined in transwell assays, and on the wound-healing, although a qualitative result, the reduction of migration induced by PDGF-BB. The 60% reduction by PDGF-BB treatment of the contractile protein expression ?-SMA, characteristic of mature phenotype, revealed the modulation of VSMCs phenotype, and it was almost completely prevented by treatment with the complex. Such prevention was associated with inhibition by almost 50% of phosphorylation of the transcription factor ELK-1 stimulated by PDGF-BB. The responses determined with complex treatments revealed promising for future development of cardiovascular devices. Although its xii mechanism of action is not completely understood, this complex showed singular biological activity, and its application in some clinical conditions where there is uncontrolled proliferation and migration of VSMCs presents as a substancial proposal / Mestrado / Fisiologia / Mestra em Biologia Funcional e Molecular
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Bridging the gaps? : Practitioner’s attitudes and understanding of the temporal,institutional and funding gaps between humanitarian anddevelopment assistanceNilsson, Rakel January 2017 (has links)
Due to an increased humanitarian caseload the UN has called for the international community to work differently from delivering aid to ending needs, partly by enhancing the engagement between humanitarian and development actors. The thesis aims to describe and analyse the dynamics between humanitarian and development aid and by so doing provide an empirical contribution to the larger discussion on how to streamline international assistance by addressing the temporal, institutional and funding gaps between the two types of assistance. This is a qualitative comparative study based on nine interviews with development and humanitarian practitioners from five different organisations providing both types of assistance. Participants of the study were positive to the idea of collaboration across the sectors but that in order to accomplish this the international community, donors and each individual organisation need to overcome great institutional and financial constraints leading to the conclusion that international assistance will not be streamlined successfully until the institutional and funding gaps are properly addressed.
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The development of the rural water supply and sanitation sector in Zimbabwe between 1974 and 1987 : the design and impact of donor supported projectsBoydell, Robert Arthur January 1990 (has links)
Although the International Drinking Water Supply and Sanitation Decade has generated great interest from foreign aid donors, its impact. in terms of increased service levels has been poor. These disappointing results have been explained by the UN and other donors in terms of inadequate funding and lack of cost recovery, poor operations and maintenance, lack of personnel, unacceptable technology, poor logistics and non involvement of the beneficiaries. However, an alternative explanation revolves around factors contributing to poor project design. These include the lack of understanding of the development process, donor bias and self interest, and poor coordination and commitment by the recipient government. A review of the development and trends of contemporary aid philosophy and its translation in to rural development and water and sanitation projects, which led to the launch of the IDWSSD, provides a number of lessons that can be used to formulate a hybrid model for project design and the sector development process, that defines the relative roles of donors, recipient governments and people themselves. The model is based on coordinated development, community participation, and sector growth from pilot projects to large scale programmes. The developments in the rural water and sanitation sector that took place in Zimbabwe from 1974 to 1987, provide a unique opportunity to test this model using a systems analysis approach. After gaining Independence in 1980, Zimbabwe's development assistance funding grew tenfold with the influx of foreign donors, and major commitments were made by the new Government to rural development and the goals of the IDWSSD. However, the large investments in water and sanitation which included the preparation of a national master plan with external technical assistance, had both positive and negative impacts on the continuing development of the sector, the start of which can be traced back, well before Independence, to small pilot projects sponsored by non government organizations that used appropriate technology developed by the Rhodesian Government. This development process and the changing approach to project design is illustrated by a series of case studies of projects supported by multilateral and bilateral donors, and non government organizations, that were milestones during this period. Finally the project and sector development model is modified based on the practical lessons from Zimbabwe and recommendations for future practice are made together with suggestions for areas of further research.
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Factors determining the composition of a public cord blood stem cell bank including HLA diversityMellet, Juanita January 2013 (has links)
The human leukocyte antigen (HLA) is the most polymorphic region in the human genome and accounts for more than 10% of human diversity. This region plays an important role in matching donors and recipients for transplantation. The South African Bone Marrow Registry (SABMR) does not reflect the demographics of the South African population. The large number of polymorphisms resulting from HLA diversity in the Black South African population and their limited representation in the SABMR reduce the chances of finding adequate matches between donors and recipients in this group. Umbilical cord blood is an alternative to bone marrow for the treatment of fatal diseases. Less strict HLA matching is required due to the naive nature of the T cells in cord blood. A public umbilical cord blood bank is a necessity in trying to cater for the diverse population in South Africa. However, the ethnic diversity of the South African population poses a great challenge in constituting a public umbilical cord blood bank that is representative of the entire population. The Roche designed next generation sequencing (NGS) high resolution (HR) HLA typing kit enables sequencing of additional HLA exons and could improve the degree of matching between individuals to ultimately decrease adverse reactions. An extensive study of the literature was performed to establish the demographics, linguistics, and HLA diversity of the South African population to determine how a public cord blood bank should be constituted. In addition, HLA genotyping was performed by 454 NGS on 20 samples that had previously been HLA typed by conventional methods. The 454 NGS technique made use of a Roche designed medium and high resolution HLA typing kit to genotype the samples. It was possible to assign accurate genotypes to 95.5% of the loci of interest for the total number of 20 samples using the MR kit, compared with 98.5% using the HR kit. In conclusion, the present study indicates the extreme HLA diversity in the South African population, and therefore, recommends constituting the first public umbilical cord blood bank in Gauteng on the basis of race or major ethnic groupings. A minimum number of 10 000 cord blood units is needed to initiate the bank. Furthermore, the 454 NGS platform together with the HR HLA typing kit display potential as an alternative method to be used in a public cord blood bank, as well as routine clinical and diagnostic laboratories, to ultimately improve HLA matching between donors and recipients. / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / Immunology / unrestricted
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The characterization of bulk as-grown and annealed ZnO by the Hall effectKassier, Gunter Horst 25 July 2007 (has links)
A fully automated Temperature Dependent Hall (TDH) measurement setup has been assembled for the purposes of this study. This TDH setup is capable of measuring samples in the 20 K to 370 K temperature range. Sample sizes of up to 20 mm × 20 mm can be accommodated by the custom designed and manufactured sample holder. Samples with a resistance in the 1Ω to 250 MΩ range can be measured with this setup provided that the mobility of the sample is greater than 1 cm²/Vs. The computer program controlling the automated measurement processwas written in LabView™ version 6.1. Single crystal Zinc Oxide (ZnO) was the material under investigation in this study. Bulk ZnO samples grown by three different methods, namely pressurized melt growth, seeded chemical vapor transport (SCVT) growth and hydrothermal growth, were measured in the 20 K to 370 K range. The effect of annealing in argon atmosphere in the 550 ºC to 930 ºC range was investigated on all three ZnO types. In addition, hydrogen-implanted layers on semi-insulating hydrothermally grown ZnO were studied. These samples were annealed in the 200 ºC to 400 ºC range and Hall measurements in the 20 K to 330 K range were performed. Programs were written to fit, wherever possible, the obtained temperature dependent carrier concentration and mobility profiles to suitable theoretical models. The carrier concentration data was fitted to a multi-donor single acceptor charge balance equation for the purpose of extracting donor concentrations and activation energies. Before fitting, the data was corrected for the Hall scattering factor and, where necessary, for two-layer effects particularly a degenerate surface conduction channel that developed through annealing on the SCVT-grown and hydrothermally grown samples. The acceptor concentrations of the samples were obtained by fitting the mobility data to a model based on D.L. Rode’s method of solving the Boltzmann transport equation. Scattering mechanisms included in the model were piezoelectric and deformation potential acoustic modes, polar optic modes and ionized impurity scattering. It was found that the mobility data did not fit the model very well without assigning questionable values to other parameters, in this case the deformation potential. Plausible values for the acceptor concentration were however obtained. The carrier concentration data fitted the model well, but due to the large number of parameters to be extracted (up to six parameters in the case of three donors) there was often not much certainty in the extracted values This study shows that TDH analysis is a valuable tool to assess the quality of semiconductors. Bulk and degenerate surface (or interfacial) conduction are separated with relative ease, and shallow defect concentrations as well as compensation level concentrations could be extracted. The generally observed uncertainty in values obtained in the multi-parameter regression of carrier concentration data indicates that supplementary techniques such as photoluminescence are needed to support results obtained by the TDH technique. / Dissertation (MSc (Physics))--University of Pretoria, 2007. / Physics / MSc / unrestricted
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Captação de órgãos em Sergipe e fatores associados à efetivação de potenciais doadoresNogueira, Emília Cervino 07 January 2009 (has links)
A disproportion exists between the number of patients in wait list for transplant and the organ procurement, that it can be related to possible flaws in the potential donors identification. To estimate the number of potential organ donors in Sergipe; to characterize the potential donors; to determine the frequency of donation and to know the factors associated to the no donation. Quantitative, descriptive and retrospective study using data collected from the medical records of patients up to 65 years old dead for traumatic brain injury,
cerebrovascular stroke and primary brain tumor in the years 2005 to 2007 in three hospitals of Aracaju. Of 766 medical records analyzed, 257 had suggestive registration of brain death, being 148 with the Term of Declaration filled out. Eighty
five percent of the potential donors were at the Public Hospital A. The median age was 33 years; prevailing the male (71,6%), the victims of traumatic brain injury (59,5%), and that in Urgency Unit (35,8%) and Intensive Therapy Unit (34,5%). Half of them presented signs of brain death in the first two days of hospitalization. Sixteen (10,8%) potential donors completed all the exams of the protocol of brain death and 12 (8,1%) became effective donors, being the absence of the diagnosis of brain death the principal cause of no donation. The time between the first registration and the
removal of the organs was inferior at 40 hours in 50% of the donors. The number of potential organ donors in Sergipe has been underestimated due to flaws in the diagnosis and in the notification, resulting in a low donation index. The rates of family refuse and irreversible cardiac arrest suggest the need of educational actions driven to the health professionals and the society in general. / Existe uma desproporção entre o número de pacientes em lista de espera para transplante e a obtenção de órgãos, que pode estar relacionada a possíveis falhas na identificação dos potenciais doadores. Estimar o número de potenciais doadores de órgãos em Sergipe; caracterizar os potenciais
doadores; determinar a freqüência de efetivação de doação e conhecer os fatores associados à não doação. Estudo quantitativo, descritivo e retrospectivo utilizando dados dos prontuários de pacientes até 65 anos de idade que faleceram por traumatismo crânio-encefálico, acidente vascular encefálico e neoplasia primária do sistema nervoso central nos anos 2005 a 2007 em três hospitais de Aracaju. Dos 766 prontuários analisados, 257 tiveram registro sugestivo de morte encefálica, sendo 148 com o Termo de Declaração preenchido. Oitenta e cinco por cento dos potenciais doadores se encontravam no Hospital Público A. A mediana da
idade foi de 33 anos, com predomínio do sexo masculino (71,6%). A causa de óbito mais freqüente foi o traumatismo crânio encefálico (59,5%). A maioria encontrava-se internada nas unidades de Urgência (35,8%) e de Terapia Intensiva (34,5%). Metade deles apresentou sinais de morte encefálica nos dois primeiros dias de hospitalização. Dezesseis (10,8%) potenciais doadores completaram todos os exames do protocolo de morte encefálica e 12 (8,1%) se tornaram doadores efetivos, sendo a ausência do diagnóstico da morte encefálica a principal causa da não efetivação da doação. O tempo entre o primeiro registro e a remoção dos órgãos foi inferior a 40 horas em 50% dos doadores. O número de potenciais doadores de órgãos em Sergipe tem sido subestimado devido a falhas no diagnóstico e na notificação, resultando em um baixo índice de doação. As taxas de recusa da família e parada cardíaca irreversível sugerem a necessidade de ações educativas dirigidas aos profissionais de saúde e à sociedade em geral.
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G-CSF in Healthy Allogeneic Stem Cell DonorsHölig, Kristina 05 August 2020 (has links)
Mobilization of peripheral blood stem cells (PBSC) in healthy volunteers with granulocyte colony-stimulating factor (G-CSF) is currently carried out at many institutions worldwide. This report presents the experience of the Dresden center regarding donor evaluation and mobilization schedule. Data regarding efficacy, short- and long-term safety of G-CSF treatment gained from 8290 PBSC collections in healthy donors are outlined. These results are discussed against the background of the available evidence from the literature. Although established as a standard procedure, G-CSF application to allogeneic donors will always be a very delicate procedure and requires the utmost commitment of all staff involved to ensure maximum donor safety. (PBSC) donation does not require hospitalization and is generally assumed to be less physically demanding for the donor. However, application of mobilizing agents is stringently required for successful HSC mobilization. The standard substance, which is almost exclusively used in healthy donors worldwide, is recombinant human granulocyte colony-stimulating factor (rhG-CSF). Two preparations – filgrastim and lenograstim – are available and have been approved for PBSC mobilization for about 15 years in Germany. Currently, more than 20,000 healthy donors worldwide receive rhG-CSF for PBSC mobilization every year [7]. At the Dresden University Hospital, PBSC collections have been performed since 1996. In the two collection facilities associated with the university hospital, 8,290 allogeneic PBSC collections from 8,005 donors (i.e. 285 second collections) have been documented in a database up until May 2012. This paper presents the data of our own group, and summarizes the current knowledge regarding the short- and long-term effects of G-CSF treatment in healthy stem cell donors.
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Česká republika jako nastupující dárcovská země a změna politiky směrem k účinnosti pomoci / The Czech Republic as an Emerging Donor Country and the Policy Change towards Aid EffectivenessTrousil, Pavel January 2012 (has links)
In an analysis of the development of the Czech foreign aid policy, I use the advocacy coalition framework (ACF) to examine what policy change towards aid effectiveness has occurred from the mid-1990's to the present. Using this explanatory framework, I suggest that the changes towards aid effectiveness, which have occurred during this period, are minor rather than major ones. I argue that during this time the Czech foreign aid policy has been dominated by a belief system of the majority coalition that represents a realistic approach to foreign aid policy based on self-interested interests such as mutual interests, commercial motives or political and strategic interests. By the application of the ACF, I attempt to explain the policy process and the reasons why a major policy change has not occurred. In this analysis, I argue that in spite of the processes external to the policy subsystem (e.g. the occurrence of aid effectiveness movement), the minority coalition, whose belief system is mainly represented by altruistic motives and the support for increasing aid effectiveness, has not had enough policy-relevant resources to press for a major policy change. I argue that the conflict between the coalitions is driven by normative beliefs and that it is more likely that there will be incremental policy...
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N-type doping of organic thin films using a novel class of dopantsWerner, Ansgar 17 June 2003 (has links)
I present a new approach to stable n-type doping of organic matrices using organic dopants. In order to circumvent stability limitations of strong organic donors, I produce the donor from a stable precursor compound in situ. As an example, the cationic dye pyronin B chloride is studied as a dopant in an 1,4,5,8-naphthalene tetracarboxylic dianhydride (NTCDA) matrix. A field effect and conductivity study of a series of doped NTCDA samples is carried out. It proves the increase of the electron density with the doping concentration. Conductivities up to 1.9*10^-4 S/cm are obtained for doped NTCDA, which is two orders of magnitude higher than the conductivity of NTCDA doped with (bis(ethylenedithio)-tetrathiafulvalene (BEDT- TTF) as investigated previously [A. Nollau, M. Pfeiffer, T. Fritz, K. Leo, J. Appl. Phys. 87, 4340 (2000)], and four orders of magnitude higher than nominally undoped NTCDA films. The experimental trends in the field effect study are interpreted in terms of transport in disordered solids. Detailed mass spectroscopic investigation are carried out to investigate the sublimation behaviour of the organic salt pyronin B chloride. We conclude that mainly HCl and the leuco base of pyronin B is present in the gas phase. Optical absorption spectroscopy shows that the leuco base is transformed to the pyronin B cation in air. A similar reaction is observed for mixed thin films of pyronin B and tetracyano quinodimethane. This supports the image of the doping process being due to an electron transfer from the pyronin to the matrix molecules. The formation of the leuco base and subsequent oxidation to the pyronin B cation is supported by Fourier transform infrared (FTIR) absorption spectroscopy. Doping experiments with other matrices reveal that the doping effect is universal for all materials of moderate acceptor strength. Matrices such as perylene-3,4,9,10-tetracarboxylic dimethyl diimide (Me-PTCDI) and fullerene C60 can be successfully doped. These compounds are frequently employed electron transport materials in organic solar cells. Therefore, such devices can be improved by this new doping approach. / In dieser Arbeit wird ein neuer Ansatz zur n-Dotierung organischer Dünnschichten mit organischen Dotanden vorgestellt. Die bisher zur n-Dotierung benötigten starken Donormoleküle zeigen eine hohe Reaktivität. Dies erschwert die Synthese und weiterhin die Verwendung solcher Verbindungen als Dotanden. Zur Vermeidung dieser Stabilitätsprobleme wird in dieser Arbeit der reaktive Dotand in situ aus einer stabilen Vorläüuferverbindung erzeugt. Beispielhaft wird der kationische Farbstoff Pyronin B Chlorid als Dotand in einer 1,4,5,8-Naphthalen Tetracarbonsäure Dianhydrid (NTCDA)-Matrix untersucht. Feldeffekt- und Leitfähigkeitsuntersuchungen an einer Serie von dotierten Dünnschichten werden durchgeführt. Eine Erhöhung der Elektronendichte mit der Dotierkonzentration wird gefunden. Dies führt zu Leitfähigkeiten von bis zu 1.9*10^-4 S/cm, d.h. vier Größenordnungen höher als undotiertes NTCDA und zwei Größenordnungen höher als das früher untersuchte NTCDA, dotiert mit Bis(Ethylendithio)-Tetrathiafulvalen (BEDT- TTF) [A. Nollau, M. Pfeiffer, T. Fritz, K. Leo, J. Appl. Phys. 87, 4340 (2000)]. Die Abhängigkeiten der elektrischen Kenngrößen Leitfähigkeit, Beweglichkeit und Ladungsträgerdichte werden anhand eine Modells erklärt, das den Transport in ungeordneten Systemen beschreibt. Massenspektrometrische Untersuchungen werden zur Untersuchung des Verdampfungsverhaltens des organischen Salzes Pyronin B Chlorid eingesetzt. Es wird gefunden, daß Pyronin B Chlorid durch Bildung von HCl und der Leukobase des Pyronins in die Gassphase übergeht. In der optische Absorptionsspektroskopie ist die Transformation der Leukobase unter Lufteinfluß in das Pyronin B-Kation zu beobachten. Das gleiche Verhalten wird für Mischschichten aus Pyronin B und Tetracyano Chinodimethan gefunden. Dies bestätigt die Vorstellung des Dotierprozesses als Elektronentransfer vom Pyronin B zum Matrixmolekül. Die Bildung der Leukobase und die anschlie\ss ende Oxidierung zum Pyronin B-Kation ist auch in der Infrarotspektroskopie sichtbar. Der Dotiereffekt ist nicht auf NTCDA beschränkt, sondern wird auch für andere Matrizen mit genügend hoher Elektronenaffinität gefunden. Matrixmaterialien wie z.B. Perylen-3,4,9,10-Tetracarbonsäure Dimethyldiimid (Me-PTCDI) und Fulleren C60 werden erfolgreich dotiert. Sie werden üblicherweise in organischen Solarzellen eingesetzt. Durch den hier demonstrierten Ansatz können folglich solche Bauelemente verbessert werden.
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An analysis of the factors that motivate undergraduate alumni donors at University of the Pacific based on social exchange theoryDial, Janet Schellhase 01 January 2010 (has links) (PDF)
Institutions of higher education rely upon the support of their alumni to provide financial stability. This outward show of confidence by alumni is also an important indication for external constituents who rank colleges and universities based on funding sources such as corporations and foundations. Private universities, in particular, have been cultivating their alumni to support their alma maters through annual and endowed gifts to provide the financial support to continue educating future generations of students. This study surveyed undergraduate alumni from the University of the Pacific through a voluntary questionnaire that was made available to alumni through the alumni e-news letter, "What's Up, Pacific?" The purpose of the study was to analyze the factors that motivate undergraduate alumni at the University of the Pacific to make gifts to their alma mater and to examine if social exchange theory can be applied to the giving behaviors of these alumni. The research questions that were addressed were 1) to what extent were Pacific alumni satisfied with their University of the Pacific experiences as a student and as alumni, 2) what internal and external factors motivate these alumni to make a gift, regardless, of the amount to the university, and, 3) how does social exchange theory serve to explain, at least in part, the behavior underlying alumni giving patterns at the University of the Pacific? Descriptive statistics and cross-tabulations were developed to analyze the data which showed that the vast majority of alumni were overall satisfied with their experiences as students (95%) and as alumni (76%). The motivators that alumni sited as the most likely to compel them to make a gift included satisfaction with their Pacific experience, commitment to support future generations of Pacific students, wanting to further the cause of the university, the importance of giving back, and the fact that giving to their alma mater makes them feel good. There were many open ended comments that support the social exchange theory as it serves to explain donor behavior. Recommendations for further research were included in the dissertation.
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