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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.
1

An investigation into the usage and learning of discretionary computer users

Maskery, Helen S. January 1987 (has links)
A new and fast-growing group of computer users is appearing. These are professionals, managers and such like, who want to use computers in the course of their work. They have choice over their use of the computers unlike 'traditional' naive users. This discretion means that they can decide not to use a computer and this difference means that the research conducted into, and the design guidelines for, non-discretionary naive users may not be appropriate for the discretionary users.
2

Estudo de utilização de psicofármacos em Ribeirão Preto - SP / A psychotropicdrugs use studyat Ribeirão Preto - Stateof São Paulo

Ferreira, Iahel Manon de Lima 13 May 2016 (has links)
Os estudos da utilização de medicamentos refletem o que acontece com os medicamentos num ambiente com variáveis não-controladas, ao contrário do que acontece nos ensaios clínicos. Dessa forma, este estudo visa determinar o consumo de psicofármacos, contextualizando-o com o crescimento populacional no município de Ribeirão Preto - SP no período de 2008 a 2012, bem como descrever o principal grupo consumidor. Para isto, este estudo observacional analítico transversal foi conduzido por meio do levantamento do uso de psicofármacos por meio dos bancos de dados Hygia (banco de dados da Secretaria Municipal de Saúde de Ribeirão Preto). Os medicamentos utilizados foram classificados de acordo com a classificação Anatômica Terapêutico Química (ATC) e suas quantidades foram expressas em Doses Diárias Definidas (DDD) a cada 1.000 habitantes por dia (DHD) e em Dose Diária Prescrita (DDP). Exceto para a faixa etária de 0 a 9 anos, em que o consumo tanto de medicamentos no geral quanto de psicofármacos foi maior ou igual para os homens; nas demais faixas etárias observa-se o consumo igual ou maior para todos os medicamentos, sendo o aumento no consumo correlacionado com o aumento da idade das mulheres. Para a maioria dos psicofármacos nota-se uma diferença significativa quando o valor da DDP foi comparado ao da DDD. Quando a taxa de aumento no consumo dos psicofármacos foi comparada a taxa do crescimento populacional, apenas o crescimento no consumo do clonazepam e da sertralina superam o crescimento populacional. Dessa forma, nota-se a importância de estabelecer comparações dos resultados encontrados dos trabalhos que avaliem a utilização de medicamentos com outras variáveis, como no caso, a taxa de crescimento populacional, para se ter uma real dimensão do seu aumento. / The drug utilization studies reflect what happens to the drug in an environment with non-controlled variables, unlike what happens in clinical trials. Thus, this study aims to determine the consumption of psychotropic drugs, contextualizing it with the population growth in RibeirãoPreto - SP from 2008 to 2012, as well as describing the main consumer group. Therefore, this cross-sectional analytical observational study was conducted through survey of the use of psychotropic drugs through databases Hygia (the RibeirãoPreto\'s Municipal database). The drugs used were classified according to the Anatomical Therapeutic Chemical classification (ATC) and their amount were expressed in Defined Daily Dose (DDD) per 1000 inhabitants per day (DHD) and Prescribed Daily Dose (PDD). Except for the age group 0-9 years, when the demand for both drugs in general and of psychotropic drugs was higher than or equal to men; in other age groups was observed a consumption equal to or greater for all medicines, the increase in consumption related with the increasing of women\' age. For most psychotropic drugs a significant difference was noticed when the value of PDD was compared to DDD. When increase rate in the consumption of psychotropic drugs was compared the rate of population growth, only the growth in consumption of clonazepam and sertraline exceed population growth.In this way, the importance of comparisons of the founded results of studies were highlighted; assessing the use of medications with other variables, as in the case, the rate of population growth, to have a real size of its increase.
3

Estudo de utilização de psicofármacos em Ribeirão Preto - SP / A psychotropicdrugs use studyat Ribeirão Preto - Stateof São Paulo

Iahel Manon de Lima Ferreira 13 May 2016 (has links)
Os estudos da utilização de medicamentos refletem o que acontece com os medicamentos num ambiente com variáveis não-controladas, ao contrário do que acontece nos ensaios clínicos. Dessa forma, este estudo visa determinar o consumo de psicofármacos, contextualizando-o com o crescimento populacional no município de Ribeirão Preto - SP no período de 2008 a 2012, bem como descrever o principal grupo consumidor. Para isto, este estudo observacional analítico transversal foi conduzido por meio do levantamento do uso de psicofármacos por meio dos bancos de dados Hygia (banco de dados da Secretaria Municipal de Saúde de Ribeirão Preto). Os medicamentos utilizados foram classificados de acordo com a classificação Anatômica Terapêutico Química (ATC) e suas quantidades foram expressas em Doses Diárias Definidas (DDD) a cada 1.000 habitantes por dia (DHD) e em Dose Diária Prescrita (DDP). Exceto para a faixa etária de 0 a 9 anos, em que o consumo tanto de medicamentos no geral quanto de psicofármacos foi maior ou igual para os homens; nas demais faixas etárias observa-se o consumo igual ou maior para todos os medicamentos, sendo o aumento no consumo correlacionado com o aumento da idade das mulheres. Para a maioria dos psicofármacos nota-se uma diferença significativa quando o valor da DDP foi comparado ao da DDD. Quando a taxa de aumento no consumo dos psicofármacos foi comparada a taxa do crescimento populacional, apenas o crescimento no consumo do clonazepam e da sertralina superam o crescimento populacional. Dessa forma, nota-se a importância de estabelecer comparações dos resultados encontrados dos trabalhos que avaliem a utilização de medicamentos com outras variáveis, como no caso, a taxa de crescimento populacional, para se ter uma real dimensão do seu aumento. / The drug utilization studies reflect what happens to the drug in an environment with non-controlled variables, unlike what happens in clinical trials. Thus, this study aims to determine the consumption of psychotropic drugs, contextualizing it with the population growth in RibeirãoPreto - SP from 2008 to 2012, as well as describing the main consumer group. Therefore, this cross-sectional analytical observational study was conducted through survey of the use of psychotropic drugs through databases Hygia (the RibeirãoPreto\'s Municipal database). The drugs used were classified according to the Anatomical Therapeutic Chemical classification (ATC) and their amount were expressed in Defined Daily Dose (DDD) per 1000 inhabitants per day (DHD) and Prescribed Daily Dose (PDD). Except for the age group 0-9 years, when the demand for both drugs in general and of psychotropic drugs was higher than or equal to men; in other age groups was observed a consumption equal to or greater for all medicines, the increase in consumption related with the increasing of women\' age. For most psychotropic drugs a significant difference was noticed when the value of PDD was compared to DDD. When increase rate in the consumption of psychotropic drugs was compared the rate of population growth, only the growth in consumption of clonazepam and sertraline exceed population growth.In this way, the importance of comparisons of the founded results of studies were highlighted; assessing the use of medications with other variables, as in the case, the rate of population growth, to have a real size of its increase.
4

The role of education in shaping the attitudes of Saulspoort region communities towards the utilisation of water as an environmental resource

Sefike, Lillian Disebo 15 June 2004 (has links)
South Africa is a water - scarce country and will be facing a serious water shortage by approximately 2020. The study, that aims to establish attitudes towards the use of water and to examine the role of education in ensuring responsible use of water, focuses on Moruleng village which was selected as representational of the 28 villages of Saulspoort region. The outcomes of the literature review which examined water consumption patterns in rural areas prompted the conducting of focus group interview with four categories of villagers from the Moruleng village. Personal observations supported by photographs and follow-up interviews with individuals featured in the photographs supplemented the interview data. The study evidenced that water consumption patterns in rural communities are indicative of attitudes. Villagers' attitudes towards water and its use are ambiguous. The study purposes to examine the possible options to inculcate positive attitudes towards water and its use through the recommendations contained in the study. / Educational Studies / M.Ed.(Environmental Education))
5

從電子期刊使用探討圖書館期刊館藏發展--以政治大學傳播學院為例 / A Study on Serials Collection Development from the Viewpoint of Electronic Journals Use: A Case Study of Communication Library at National Cheng-Chi University

陳巧倫 Unknown Date (has links)
著電子期刊發展日益成熟,圖書館引進電子期刊館藏蔚為風尚,對圖書館紙本期刊的發展與學術傳播都帶來了巨大的影響。圖書館期刊館藏的改變,也連帶對於使用者的期刊使用造成影響。本研究旨在了解傳播學門教師電子期刊的使用行為,並從使用者的角度探討電子期刊對圖書館館藏發展之影響進而研訂以使用者角度為導向的電子期刊館藏發展政策,以做為未來圖書館館藏發展之參考。 本研究利用問卷調查與深度訪談以了解政大傳播學院教師的資訊行為與電子期刊的使用情形,以及政大傳傳播學院圖書館館藏發展現況、所面臨的問題與困難與對未來館藏發展之看法。最後獲致研究結論如下:(1)傳播學院教師平時的主要任務以教學與研究為主,而資訊需求也多因教學與研究而產生;(2)學術期刊是教師教學與研究的最重要資源;(3)傳播學院教師使用電子期刊甚於紙本期刊;(4)教師對傳播學院圖書分館期刊館藏與服務感到滿意;(5)傳播學院圖書分館重視發展學術期刊館藏,並以西文期刊為館藏重要特色;(6)傳播學院圖書分館期刊館藏發展以電子期刊與紙本期刊並重;(7)傳播學院圖書期刊選購由教師決定,主要考慮期刊內容學術性與教師需求;(8)獲得政大傳播學院圖書分館電子期刊館藏發展要件與程序;(9)傳播學院圖書分館經費有限與典藏空間不足促使電子期刊館藏發展的需求;(10)獲得政大傳播學院圖書館紙本期刊刪訂決策因素;(11)政大傳播學院圖書分館缺乏館藏發展政策訂定;(12)多數教師同意政大傳播學院圖書分館有發展電子期刊之需求;(13)多數教師對於全面發展電子期刊的看法仍有疑慮。 本研究最後針對圖書館電子期刊館藏發展與服務提出以下建議:(1)依據教師使用行為加強電子期刊館藏服務;(2)傳播學院三系所建立期刊選購合作機制;(3)訂定傳播學院圖書分館電子期刊館藏發展政策;(4)加強使用者電子期刊使用教育訓練;(5)強化傳播學院圖書分館館員的功能與價值。 / With the great developments of electronic journals, it becomes a trend for academic libraries to purchase a large amount of electronic resources. Electronic journals bring a lot of impacts on the academic libraries and scholarly communication. The changes on library serials collection also affect the way that faculty use scholarly journals. This research investigated the use of electronic journals among the faculty of Communication at the Cheng-Chi University, and tried to use user-oriented approach to formulate the serials collection development policy. The research conducted at the Cheng-Chi University in 2008 by questionnaire and interviews to exam the use of electronic journals by the faculty of Communication, investigate the status of serials collection in Communication Library, and obtain the faculty and librarians’ viewpoints about the future of serials collection development. The research findings are as follow: (1) The information needs of faculty of communication most came from research and teaching. (2) Scholarly journals are essential resources in the field of communication. (3) Faculty of communication rely on electronic journals than print journals. (4) Faculty are satisfied with the serials collection and services provided by communication library. (5) Communication library set great store by developing academic journals collections and foreign languages journals are features of communication library. (6) Emphasizing electronic journals and print journals equally is the main collection development strategy of communication library. (7) The purchases of journals are decided by faculty, and the technicality and needs of teachers are the two major factors that have great impact on serials selection. (8) Formulate procedures and components of serials collection development for communication library. (9) Shortage of budget and shelving space made communication library has need to develop electronic serials collection. (10) Formulate factors of serials cancellation for communication library. (11) Communication library need to establish collection development policy. (12) A majority of faculty agree that communication library need to develop electronic serials collection. (13) The mostly concerned issue when the library develops the whole electronic journal collection is the electronic archiving. Based on the final results of this research, several suggestions are proposed for improving communication library serials collection development and services are as follow:(1) Strengthen electronic journals collection services based on patterns of journal use by faculty. (2) The college of communication should build cooperation mechanisms for purchasing journals. (3) Communication library should establish electronic serials collection development policy. (4) Enhance training in e-resource use to faculty and students. (5) Strengthen the function and value of librarians in communication library to become the intermedium between main library and faculty.
6

Tłı̨chǫ women and the environmental assessment of the NICO Project proposed by Fortune Minerals Limited

Kuntz, Janelle 31 August 2016 (has links)
This thesis reviews the participation of Tłı̨chǫ women in the environmental assessment (EA) of the NICO project proposed by Fortune Minerals Limited. Undertaken in 2012 in the Northwest Territories, this particular EA saw a precedential engagement between traditional knowledge and western science. Although this EA did not take a gendered approach, Tłı̨chǫ women’s stories and participation in the EA supported the Tłı̨chǫ Government’s interests throughout the review process and in the final mitigation measures. Predominate scholarship does not typically cast Indigenous women as participants in or beneficiaries of EAs and resource extraction projects. Results from this thesis support more recent scholarship that urges for an ethnographic and contextual analysis of each scenario. Ethnographic methods helped me to reveal the culturally specific, diverse and complex ways Tłı̨chǫ women participated and shared their stories in the Fortune Minerals EA. Tłı̨chǫ women’s stories, I found, were important and relevant to the Mackenzie Valley Environmental Impact Review Board’s assessment of the potential social and ecological impacts of the NICO project. I conclude that this EA is exemplary of Indigenous women’s agency within a regulatory process and offer suggestions for how to incorporate a gender-based analysis into future EA processes. / Graduate / 0733 / 0326 / janellek@uvic.ca
7

The role of education in shaping the attitudes of Saulspoort region communities towards the utilisation of water as an environmental resource

Sefike, Lillian Disebo 15 June 2004 (has links)
South Africa is a water - scarce country and will be facing a serious water shortage by approximately 2020. The study, that aims to establish attitudes towards the use of water and to examine the role of education in ensuring responsible use of water, focuses on Moruleng village which was selected as representational of the 28 villages of Saulspoort region. The outcomes of the literature review which examined water consumption patterns in rural areas prompted the conducting of focus group interview with four categories of villagers from the Moruleng village. Personal observations supported by photographs and follow-up interviews with individuals featured in the photographs supplemented the interview data. The study evidenced that water consumption patterns in rural communities are indicative of attitudes. Villagers' attitudes towards water and its use are ambiguous. The study purposes to examine the possible options to inculcate positive attitudes towards water and its use through the recommendations contained in the study. / Educational Studies / M.Ed.(Environmental Education))
8

A psycho-educational programme using audio-visual media for the prevention of adolescent substance abuse

Calder, Bruce Donovan 08 1900 (has links)
South Africa has been witnessing an escalation in drug use amongst adolescents in high school. Thus, the main question that motivated this research was: How can a psycho-educational programme, using a selected audio-visual media resource, assist teachers and parents in an effort to prevent adolescent students’ substance abuse problem behaviour? Social cognitive theory (SCT) and self-efficacy theory (SET) were used as a conceptual framework. The study explained these theories in-depth. Adolescent substance abuse was also studied as well as programmes to address this problem. This was followed by a perusal of numerous audio-visual resources for their possible incorporation into prevention programmes. The ‘Above The Influence’ (ATI) resource was selected for the psycho-educational programme which was designed for the study. The programme was put into action during seven sessions over a period of about two months, and implemented with a group of 26 Grade 10 and Grade 11 students in Pietermaritzburg, South Africa, to evaluate its relevance for adolescent substance abuse prevention. To evaluate the programme, a qualitative approach was used. The data were gathered during the programme implementation by means of in-person and online focus groups, individual interviews, written open-ended questions, observation notes and follow-up interviews some time after the programme had ended. Eleven principles were identified from the literature to evaluate the potential of the programme to be effective in preventing adolescent substance abuse. In particular the programme needed to increase adolescents’ skills related to studying, communication, peer relationships, self-efficacy, assertiveness, and drug resistance. The programme also had to employ interactive techniques and needed to address the type of drug abuse problem in the local community, for example, the ‘gateway’ substances of marijuana, alcohol and tobacco. In addition, the programme potential was evaluated in the light of SCT and SET. The findings indicated that the psycho-educational programme, using ATI as audiovisual medium, can be used very effectively by teachers to raise students’ awareness and develop particular skills that could contribute towards the prevention of adolescent substance abuse. It is recommended that the programme should be used in the long-term with repeated reinforcing sessions over time. / Psychology of Education / D. Ed. (Psychology of Education)
9

Flavona e análogos como radioligantes para imageamento cerebral. Síntese, marcação com radioiodo e estudos in vivo frente a sítios receptores benzodiazepínicos / Flavone and analogs as radioligands for brain imaging synthesis, radioiodine labeling and in vivo studies against benzodiazepine receptor sites

Grallert, Sibila Roberta Marques 12 December 2006 (has links)
O desenvolvimento de radioligantes para o sistema nervoso central (SNC) com características radiotraçadoras que justifiquem seu uso em diagnóstico por geração de imagens é esperado pela comunidade médica nuclear. Os benzodiazepínicos flumazenil-11C e iomazenil-123I são utilizados, com limitações, para investigações clínicas de densidade de sítios receptores benzodiazepínicos no cérebro em patologias como Alzheimer, epilepsia e depressão, entre outras. No Brasil, entretanto, estes traçadores ainda não estão disponíveis para uso clínico. Neste sentido, os flavonóides têm despertado interesses como perspectiva de nova classe de compostos com atividade no SNC podendo originar radiotraçadores com perspectivas para aplicação em imageamento cerebral. Baseado no exposto, a proposta deste estudo envolve o planejamento, a síntese e a marcação com radioiodo (131I e 123I) de flavona e análogos, o controle de qualidade radioquímico, os estudos de biodistribuição e o imageamento, para a avaliação do perfil de captação desses compostos e potencial aplicação em estudos cerebrais, frente a sítios receptores benzodiazepínicos. Os compostos estudados neste trabalho foram obtidos empregando-se a transformação de Baker-Venkataraman. A flavona e análogos foram identificados através de espectros de RMN-1H, RMN-13C e IV. O grau de pureza das substâncias obtidas foi confirmado através da medição da faixa de fusão. Os compostos radiomarcados foram obtidos com alta pureza radioquímica por substituição eletrofílica aromática direta. Esta marcação propiciou estabilidade in vitro após 24 horas e, para a flavona radiomarcada estabilidade in vivo, uma vez que a tireóide não apresentou captação significativa em tempos menores que 1 hora e excreção favorável no tempo de 24 horas. Os estudos de biodistribuição foram realizados em camundongos Swiss, verificando-se alta concentração de flavona-iodo-131 no cérebro, principalmente até 30 minutos após a injeção intravenosa e eliminação favorável após 24 horas de estudo. As imagens cerebrais foram realizadas em coelho New Zeland e em ratos Wistar adquiridas em gama câmara analógica sugerindo que a captação desse ligante no cérebro em tempos curtos, até 30 minutos, viabiliza a aquisição de imagens cintilográficas. Adicionalmente, foram desenvolvidos estudos de modelagem molecular da flavona e da flavona radiomarcada, utilizando-se mecânica quântica AM1 semi-empírico, corroborando a reatividade química desse composto frente à marcação com radioiodo por substituição eletrofílica, processo controlado predominantemente por interações eletrostáticas. Foram calculados os valores individuais de cargas para cada carbono da estrutura da flavona, incluindo cargas de Mulliken, Natural e Eletrostática, e foram gerados os mapas topográficos de distribuição de cargas de ambas as moléculas, evidenciando que as posições 6 e 8, na molécula de flavona, são as mais prováveis para a substituição por radioiodo. / The development of radioligands for the Central Nervous System (CNS) with adequate radiotracer characteristics for the use in imaging diagnostic has been long expected by the medical community. Benzodiazepines flumazenil-11C and iomazenil-123I are employed with limitations in clinical investigations of the density of receptor sites in the brain in pathologies such as Alzheimer, epilepsy, and depression. Nevertheless, in Brazil these radiotracers are not available in market, yet. In this respect, flavonoids has drawing attention as a perspective of a new class of compounds wit CNS activity and potential of originating radiotracers to be employed in brain imaging. Therefore, the goal of this work consisted in the planning, synthesis, and labeling with radioiodine (131I and 123I) of flavone and analogs, as well as to perform radiochemical quality control, biodistribuction, and imaging studies of the radiotracers obtained in order to evaluate the uptake profile and potential for use in cerebral studies of benzodiazepinic receptors sites. To obtain the compounds, we utilized the Baker-Venkataraman transformation, and NMR-1H, NMR-13C, and IR spectroscopy were employed for identification of the molecules. The purity of the compounds obtained was assessed by means of melting point determinations. The radiolabeled compounds were obtained by aromatic electrophilic substitution with a high degree of radiochemical purity. The labeling allowed in vitro stability after 24 hours and in vivo stability of the radiolabeled flavone, provided that the thyroid did not presented significant uptake in less than one hour and favorable excretion in 24 hours. Biodistribution studies were carried out employing Swiss mice. The results indicated high concentrations of flavone-I131 in the brain, especially in the first 30 minutes after intravenous injection, as well as favorable elimination after 24 hours. Brain images were obtained from New Zeland rabbit and Wistar rats in analogical gamma camera, suggesting that short-time brain uptake of the radioligand (up to 30 minutes) allows the acquisition of cynthilographic images. Additionally, molecular modeling studies of the flavone were performed employing the semi-empiric method of AM1. The results corroborate the chemical reactivity of the compound for labeling with radioiodine by aromatic electrophilic substitution, process that is governed mainly by electrostatic interactions. The individual values of Mulliken, Natural, and Electrostatic charges of each carbon atom in flavone structure were calculated and topographic maps of charge distribution were then generated. The analysis of the maps indicates that positions 6 and 8 in the flavone molecule are most likely to present the radioiodine substitution.
10

Flavona e análogos como radioligantes para imageamento cerebral. Síntese, marcação com radioiodo e estudos in vivo frente a sítios receptores benzodiazepínicos / Flavone and analogs as radioligands for brain imaging synthesis, radioiodine labeling and in vivo studies against benzodiazepine receptor sites

Sibila Roberta Marques Grallert 12 December 2006 (has links)
O desenvolvimento de radioligantes para o sistema nervoso central (SNC) com características radiotraçadoras que justifiquem seu uso em diagnóstico por geração de imagens é esperado pela comunidade médica nuclear. Os benzodiazepínicos flumazenil-11C e iomazenil-123I são utilizados, com limitações, para investigações clínicas de densidade de sítios receptores benzodiazepínicos no cérebro em patologias como Alzheimer, epilepsia e depressão, entre outras. No Brasil, entretanto, estes traçadores ainda não estão disponíveis para uso clínico. Neste sentido, os flavonóides têm despertado interesses como perspectiva de nova classe de compostos com atividade no SNC podendo originar radiotraçadores com perspectivas para aplicação em imageamento cerebral. Baseado no exposto, a proposta deste estudo envolve o planejamento, a síntese e a marcação com radioiodo (131I e 123I) de flavona e análogos, o controle de qualidade radioquímico, os estudos de biodistribuição e o imageamento, para a avaliação do perfil de captação desses compostos e potencial aplicação em estudos cerebrais, frente a sítios receptores benzodiazepínicos. Os compostos estudados neste trabalho foram obtidos empregando-se a transformação de Baker-Venkataraman. A flavona e análogos foram identificados através de espectros de RMN-1H, RMN-13C e IV. O grau de pureza das substâncias obtidas foi confirmado através da medição da faixa de fusão. Os compostos radiomarcados foram obtidos com alta pureza radioquímica por substituição eletrofílica aromática direta. Esta marcação propiciou estabilidade in vitro após 24 horas e, para a flavona radiomarcada estabilidade in vivo, uma vez que a tireóide não apresentou captação significativa em tempos menores que 1 hora e excreção favorável no tempo de 24 horas. Os estudos de biodistribuição foram realizados em camundongos Swiss, verificando-se alta concentração de flavona-iodo-131 no cérebro, principalmente até 30 minutos após a injeção intravenosa e eliminação favorável após 24 horas de estudo. As imagens cerebrais foram realizadas em coelho New Zeland e em ratos Wistar adquiridas em gama câmara analógica sugerindo que a captação desse ligante no cérebro em tempos curtos, até 30 minutos, viabiliza a aquisição de imagens cintilográficas. Adicionalmente, foram desenvolvidos estudos de modelagem molecular da flavona e da flavona radiomarcada, utilizando-se mecânica quântica AM1 semi-empírico, corroborando a reatividade química desse composto frente à marcação com radioiodo por substituição eletrofílica, processo controlado predominantemente por interações eletrostáticas. Foram calculados os valores individuais de cargas para cada carbono da estrutura da flavona, incluindo cargas de Mulliken, Natural e Eletrostática, e foram gerados os mapas topográficos de distribuição de cargas de ambas as moléculas, evidenciando que as posições 6 e 8, na molécula de flavona, são as mais prováveis para a substituição por radioiodo. / The development of radioligands for the Central Nervous System (CNS) with adequate radiotracer characteristics for the use in imaging diagnostic has been long expected by the medical community. Benzodiazepines flumazenil-11C and iomazenil-123I are employed with limitations in clinical investigations of the density of receptor sites in the brain in pathologies such as Alzheimer, epilepsy, and depression. Nevertheless, in Brazil these radiotracers are not available in market, yet. In this respect, flavonoids has drawing attention as a perspective of a new class of compounds wit CNS activity and potential of originating radiotracers to be employed in brain imaging. Therefore, the goal of this work consisted in the planning, synthesis, and labeling with radioiodine (131I and 123I) of flavone and analogs, as well as to perform radiochemical quality control, biodistribuction, and imaging studies of the radiotracers obtained in order to evaluate the uptake profile and potential for use in cerebral studies of benzodiazepinic receptors sites. To obtain the compounds, we utilized the Baker-Venkataraman transformation, and NMR-1H, NMR-13C, and IR spectroscopy were employed for identification of the molecules. The purity of the compounds obtained was assessed by means of melting point determinations. The radiolabeled compounds were obtained by aromatic electrophilic substitution with a high degree of radiochemical purity. The labeling allowed in vitro stability after 24 hours and in vivo stability of the radiolabeled flavone, provided that the thyroid did not presented significant uptake in less than one hour and favorable excretion in 24 hours. Biodistribution studies were carried out employing Swiss mice. The results indicated high concentrations of flavone-I131 in the brain, especially in the first 30 minutes after intravenous injection, as well as favorable elimination after 24 hours. Brain images were obtained from New Zeland rabbit and Wistar rats in analogical gamma camera, suggesting that short-time brain uptake of the radioligand (up to 30 minutes) allows the acquisition of cynthilographic images. Additionally, molecular modeling studies of the flavone were performed employing the semi-empiric method of AM1. The results corroborate the chemical reactivity of the compound for labeling with radioiodine by aromatic electrophilic substitution, process that is governed mainly by electrostatic interactions. The individual values of Mulliken, Natural, and Electrostatic charges of each carbon atom in flavone structure were calculated and topographic maps of charge distribution were then generated. The analysis of the maps indicates that positions 6 and 8 in the flavone molecule are most likely to present the radioiodine substitution.

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