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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.
131

Desafios para a implementação de compras públicas sustentáveis no Instituto Federal do Norte de Minas Gerais

Ferreira, Cláudio Márcio Dias 19 February 2018 (has links)
Submitted by Núcleo de Pós-Graduação Administração (npgadm@ufba.br) on 2018-04-24T19:35:12Z No. of bitstreams: 1 Dissertação de Mestrado-CLÁUDIO MÁRCIO DIAS FERREIRA.pdf: 4923823 bytes, checksum: 8e5fded360103458fc0be39a09837fd4 (MD5) / Approved for entry into archive by Maria Angela Dortas (dortas@ufba.br) on 2018-04-30T17:41:03Z (GMT) No. of bitstreams: 1 Dissertação de Mestrado-CLÁUDIO MÁRCIO DIAS FERREIRA.pdf: 4923823 bytes, checksum: 8e5fded360103458fc0be39a09837fd4 (MD5) / Made available in DSpace on 2018-04-30T17:41:03Z (GMT). No. of bitstreams: 1 Dissertação de Mestrado-CLÁUDIO MÁRCIO DIAS FERREIRA.pdf: 4923823 bytes, checksum: 8e5fded360103458fc0be39a09837fd4 (MD5) / Diante do iminente limite físico dos recursos naturais causado pela lógica da Economia Linear e o pujante poder de compra do setor público no Brasil, as Compras Públicas Sustentáveis (CPS) desempenham papel fundamental na implementação de políticas públicas voltadas a construção de um modelo de desenvolvimento sustentável. Entretanto, esse modelo não avançará, a menos que a economia sirva como incentivo para equilíbrio entre as dimensões da sustentabilidade no desenvolvimento das atividades humanas. Em oposição ao sistema de produção linear, emerge como proposta alternativa a Economia Circular que propõe que os materiais extraídos sejam mantidos em círculos fechados de produção, mantendo-os continuamente no máximo de seus valores, tomando os processos da natureza como modelo e mentora. Essa lógica atende ao interesse público que pauta-se em devolver para a sociedade o “melhor valor”, contínuo e sustentável das contratações públicas em longo prazo. Assim, dada a relevância do tema, enquanto instrumento da prática social incorporadora do compromisso com a perenizacão humana, somado à obrigatoriedade de incorporação pelo setor público de padrões sustentáveis nas suas compras, justifica-se o presente estudo, que tem como objetivo identificar os principais desafios enfrentados pelo Instituto Federal do Norte de Minas Gerais (IFNMG) para a implementação das CPS. Para tanto, analisou-se os aspectos da gestão e práticas organizacionais no âmbito das compras sustentáveis à luz dos dispositivos legais e normativos, os processos de auditorias e posicionamento jurisprudencial do Tribunal de Contas da União, enfatizando as evidências administrativas sobre sua evolução e obstáculos. Utilizou-se as abordagens da pesquisa bibliográfica, observação direta, análise documental, entrevistas semiestruturadas e questionários aplicados aos servidores gestores, executores, assessor jurídico e requisitantes de CPS. A análise do estudo de caso demonstra o estágio transitório, tendente a uma faixa de desempenho intermediária das CPS do IFNMG, indicando por um lado o seu avanço marcado pela inserção sistemática de critérios e práticas sustentáveis nos processos licitatórios e inciativas institucionais para conscientização ecológica. Por outro lado, os procedimentos operacionais e práticas administrativas que determinam a incorporação empírica da sustentabilidade nas compras públicas demonstram-se fragilizados e não padronizados pela ausência de normatizações socioambientais e mecanismos de informações, escassez de interação e articulação entre setores cruciais para o planejamento das CPS, ineficiência da fiscalização na execução contratual quanto ao cumprimento de práticas sustentáveis estabelecidas a ponto de comprometer a concretude das CPS. Por fim, as evidências do estudo indicam que os principais desafios das CPS no IFNMG, referem-se à deficiência institucional de capacitação e interação intersectorial afim, ausência de normatização socioambiental e planejamento das compras públicas, fragilização da fiscalização contratual, abordagem do TCU restritiva quanto a adoção de sistemas de rotulagem ambiental, sobrecarga de trabalho causada pela rigorosidade procedimental para fundamentação de tal política, coletivo legal e normativo complexo e extenso e a carência de dispositivos e marcos legais que fundamentem e proporcionem segurança jurídica para a adoção de critérios e práticas sustentáveis nas contratações públicas. / In the face of the imminent physical limit of natural resources caused by the logic of Linear Economy and the strong buying power of the public sector in Brazil, Sustainable Public Procurement (SPP) plays a fundamental role in the implementation of public policies aimed at the construction of a model of sustainable development. However, this model will not advance unless the economy serves as an incentive to balance the dimensions of sustainability in the development of human activities. Oppositional to the linear production system, the Circular Economy proposes that the extracted materials be kept in closed production circles, keeping them continuously at their maximum values, taking the processes of nature as model and mentor. This logic responds to the public interest that is aimed at giving back to society the "best value", continuous and sustainable of public procurements in the long term. Given the relevance of the theme, as an instrument of social practice incorporating the commitment to human perennialism, added to the obligation of incorporation by the public sector of sustainable patterns in its purchases, the present study is justified and whose objective is to identify the main challenges faced by the Federal Institute of North of Minas Gerais (IFNMG) for the implementation of SPP. For this purpose, we analyzed management aspects and organizational practices in the field of sustainable procurement in the light of the legal and regulatory provisions, the audit processes and jurisprudential positioning of the Federal Audit Court, emphasizing the administrative evidences on its evolution and obstacles. It was used as approaches of bibliographic research, direct observation, documentary analysis, semi-structured interviews and questionnaires applied to managers, executors, legal advisers and SPP requesters. The analysis of the case study demonstrates the transient stage, tending to an intermediate performance range of the SPP of IFNMG. So, indicating on the one hand its progress marked by the systematic insertion of sustainable criteria and practices in the bidding processes and institutional initiatives for ecological awareness. On the other hand, the operational procedures and administrative practices that determine the empirical incorporation of sustainability in public procurements prove to be fragile and non-standardized due to the lack of socio-environmental norms and mechanisms of information, lack of interaction and articulation between sectors crucial to planning of SPP, inefficiency of inspection in the contractual execution regarding compliance with sustainable practices established to the point of compromising the concreteness of the SPP. Finally, the evidences of this study indicate that the main challenges of SPP in the IFNMG refer to the institutional deficiency of training and intersectorial interaction, lack of socio-environmental standardization and planning of public procurement, weakening of contractual inspection, restrictive FAC approach regarding adoption of environmental labeling systems, work overload caused by procedural rigor to justify such a policy, legal collective and complex and extensive normative, and the lack of legal frameworks and mechanisms that underlie and provide legal security for the adoption of sustainable criteria and practices in the public procurement
132

A framework to design reverse logistics operations based on circular economy values

Ripanti, Eva Faja January 2016 (has links)
Reverse Logistics (RL) is complex to be managed due to the uncertainty involved e.g. the quality range of products, timing of product returns, and volume of returns. A robust RL design can contribute to increase the effectiveness of RL operations. Therefore, an RL design framework needs to be formalised. Circular economy (CE) focuses on supporting the separation of treatments between technical and biological materials in maximising the design for reuse to return to the biosphere and retain value through innovations across fields. The aim of the research is to develop a new framework to design RL operations based on CE values that can increase the effectiveness and efficiency of RL operations. This research has been conducted through the qualitative research involving cases in product recovery (PR) options that are analysed in-depth. Literature review and interview are the main methods of this research. A test was conducted by interviewing expert and respondents to obtain the expert view and test the research result which is a developed framework to design RL based on CE values. The testing engaged five criteria (usability, feasibility, consistency, effectiveness, and utility). The formal RL design framework, 15 CE values, framework to design RL based on CE values specifically PR options (repair, refurbishment, remanufacturing, and cannibalisation) are main research findings. The research contributes academically to the development of a formal RL design framework and to the identification, reformulation, redefinition, and implementation of CE values. The research can be used as a basis for an effective design of RL that takes into account the economic, environmental, and social impacts. The research can be used as a guideline or an appraisal tool in designing/modifying RL based on CE values that can support the implementation of a single RL operation and also RL based on CE.
133

Projeto de antena de microfita com polarização circular para aplicação em veículos aéreos não tripulados / Design of microstrip antenna with circular polarization for application in unmanned aerial vehicle

Araújo, Alexandre de Moraes 28 February 2018 (has links)
Submitted by Lara Oliveira (lara@ufersa.edu.br) on 2018-06-11T17:51:51Z No. of bitstreams: 1 AlexandreMA_DISSERT.pdf: 21200920 bytes, checksum: 988dc3f3c5290a8f67225c05b46914a0 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2018-06-18T16:52:15Z (GMT) No. of bitstreams: 1 AlexandreMA_DISSERT.pdf: 21200920 bytes, checksum: 988dc3f3c5290a8f67225c05b46914a0 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2018-06-18T16:53:10Z (GMT) No. of bitstreams: 1 AlexandreMA_DISSERT.pdf: 21200920 bytes, checksum: 988dc3f3c5290a8f67225c05b46914a0 (MD5) / Made available in DSpace on 2018-06-18T16:53:22Z (GMT). No. of bitstreams: 1 AlexandreMA_DISSERT.pdf: 21200920 bytes, checksum: 988dc3f3c5290a8f67225c05b46914a0 (MD5) Previous issue date: 2018-02-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Demand in wireless networks has increased considerably in recent years. Consequently, the study of system components has also increased. Within this context, antennas are fundamental elements in the physical layer in radiofrequency communications, and their study has become a research area with great advances. The need in certain systems for smaller antennas and more adaptability in the space makes the microstrip antennas in potential substitutes of the traditional antennas. This work aims to find prototypes of microfite antennas that have physical and electrical characteristics, such as gain and polarization, superior to the commercial antennas of a FPV communication system (First Person View) operating at 5.8 GHz. The methodology used in this research consists of a theoretical survey about circular polarization antennas, design, simulate and construct these antennas using different substrates in order to verify their performance and to ship them in an FPV system. The results obtained through the simulation are compared with the experimental results in order to attest to the model in question based on the literature used in this work. Preliminarily, the simulated and measured results show that the Triangular Patch Antennas have all the desirable characteristics for operation in the FPV system, being possible to board them for the obtaining of images and analysis of the performance of the system / A demanda em redes de comunicação sem fio tem aumentado consideravelmente nos últimos anos. Consequentemente, o estudo dos componentes dos sistemas também aumentou. Dentro desse contexto, as antenas são elementos fundamentais na camada física em comunicações via radiofrequência, e o seu estudo tornou-se uma área de pesquisa com grandes avanços. A necessidade em determinados sistemas por antenas de menor porte e mais adaptabilidade no espaço tornam as antenas de microfita em potenciais substitutos das antenas tradicionais. Diante disso, esse trabalho objetiva encontrar protótipos de antenas de microfita que possuam características físicas e elétricas, como ganho e polarização, superiores às antenas comerciais de um sistema de comunicação em FPV (First Person View), operando em 5.8 GHz. A metodologia utilizada nessa pesquisa consiste em um levantamento teórico acerca das antenas de polarização circular, projetar, simular e construir estas antenas utilizando diferentes substratos a fim de verificar seu desempenho e embarcá-las em um sistema FPV. Os resultados obtidos através da simulação são comparados com os resultados experimentais a fim de atestar o modelo em questão com base na literatura empregada neste trabalho. Preliminarmente, os resultados simulados e medidos mostram que as Antenas Patch Triangular possuem todas as características desejáveis para operação no sistema FPV, sendo possível embarcá-las para a obtenção de imagens e análise de desempenho do sistema com as mesmas / 2018-06-11
134

Influência dos parâmetros do processo de serramento no corte de capacitores de filme metalizado ultrafino

Mello, Tiago Chaves January 2015 (has links)
Visando determinar os valores ótimos para o processo de serramento de anéis bobinados de filme metalizado ultrafino de alumínio com dielétrico de poliéster a partir das condições atuais do processo de fabricação de capacitores pela empresa Epcos do Brasil, realizou-se a avaliação de diferentes tipos de serras circulares variando-se a velocidade de rotação (n) e o tempo de corte (tc). Desenvolvido projeto de experimento desses três fatores a fim de obter o resultado das interações entre eles quanto à resistência de isolamento (Riso) das peças cortadas. A serra de 160 dentes de metal-duro com revestimento de filme de carbono tipo diamante (DLC) apresentou os melhores resultados quanto à “Riso” acima de 0,378 G e quanto ao número de peças com valor abaixo deste. Constatou-se que “n” não influencia significativamente para a distribuição de “Riso”; porém, gera menos peças abaixo do especificado. Já “tc” não influencia significativamente o processo. Quanto ao tipo de dente, o perfil reto obteve melhor resultado para lâminas de serra com 80 dentes e perfil curvo para lâminas com 160 dentes. Já a espessura da lâmina não influenciou de forma expressiva o processo. A lâmina de aço-rápido apresentou adesão de alumínio na lateral do corpo da serra e, consequentemente, adesão de material na superfície de corte. As lâminas de metal-duro sem revestimento apresentaram falhas no filme metalizado por causa do atrito gerado entre a superfície de corte e a lateral da lâmina; esse inconveniente é eliminado quando ela é revestida com filme DLC apresentando melhorias quanto à “Riso” das peças para “n” menores. Também houve adesão de alumínio na parte inferior do dente devido a uma delaminação da camada de filme DLC. / In order to determine the optimal values for the sawing process of wound rings of metalized ultra-thin film with dielectric of polyester from current conditions of capacitor manufacturing process by Epcos company in Brazil, it was performed the evaluation of different types of circular saws varying the rotational speed (n) and the cutting time (tc). Developed experiment design methodology for these three factors in order to get the result of the interactions between them regarding to the insulation resistance (Riso) of cut parts. Through the analysis of the main effects, the cemented carbide saw with 160 teeth and diamond-like carbon (DLC) film coating showed the best results in terms of "Riso" above 0,378 G and regarding to the number of parts with value below the specified. It was found that "n" does not influence significantly the distribution of "Riso"; however, generates fewer parts below the specified. Now "tc" does not significantly influence the process. Regarding the tooth type, straight profile obtained better results for saw blades with 80 teeth and curved profile for blades with 160 teeth. However the thickness of the blade did not influence significantly the process. The high speed steel blade presented adhesion of aluminum on the side of the saw body and, consequently, adhesion of material on the cutting surface. The cemented carbide blades uncoated presented failures on metalized film because of the friction generated between the cutting surface and the side of the blade; this drawback is eliminated when it is coated with DLC film presenting improvements to the parts "Riso" for lower "n". There was also aluminum adhesion on the bottom of the tooth due to a delamination of the DLC film layer.
135

Relação Estrutura-Atividade de Fragmentos da Leptina / Structure-Activity Relationship of Leptin Fragments

Martins, Marta Natividade Crizol [UNIFESP] 26 March 2008 (has links) (PDF)
Made available in DSpace on 2015-07-22T20:50:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-03-26. Added 1 bitstream(s) on 2015-08-11T03:25:45Z : No. of bitstreams: 1 Publico-10806.pdf: 1743333 bytes, checksum: 379793d92e9d86096d10c579b33c757e (MD5) / A hormônio protéico produzido pelo gene-ob e denominado leptina, é um produto originário do tecido adiposo, circula pelo plasma e afeta o balanço energético interagindo em receptores presentes no hipotálamo. A leptina desempenha um papel importante na regulação de uma variedade de funções fisiológicas, incluindo controle de ingestão alimentar, temperatura corporal e manutenção do peso corporal. A ausência ou resistência a leptina pelo organismo causa obesidade mórbida, diabetes e hipogonadismo. A estrutura terciária da molécula da leptina revela a presença de quatro hélices, cujo padrão é típico das citocinas. Com o objetivo de identificar a região da molécula responsável pela expressão de sua atividade biológica foram sintetizados seis fragmentos peptídicos cujas estruturas foram escolhidas de acordo com a estrutura tridimensional da leptina. Em estudos anteriores do nosso grupo, dois peptídeos, AchLEP92- 115-NH2 (IV) e Ac-[Ser117]-hLEP116-140-NH2 (V), foram reconhecidos pelo receptor da leptina presentes em células HP-75, confirmando outros trabalhos da literatura que também apontavam que é nesta região da molécula que deve estar presente o epitopo funcional da leptina. Neste trabalho, uma nova série de fragmentos, cujas estruturas primárias estão contidas na região dos fragmentos IV e V, foram sintetizados e os efeitos dos mesmos na variação do peso corporal e no consumo de alimento quando administrados no ventrículo cerebral de ratos normais foram avaliados. Os peptídeos foram sintetizados pelo método da fase sólida manual pela estratégia t-Boc. Os mesmos foram purificados por cromatografia liquida de alta eficiência e foram caracterizados por análise de aminoácidos e cromatografia liquida acoplada a um espectrômetro de massas. Estudos conformacionais dos peptídeos também foram realizados por Dicroísmo Circular com o objetivo de correlacionar a estrutura com a atividade biológica dos fragmentos. Dentre os compostos estudados, o melhor resultado foi obtido com o fragmento AchLEP110- 119-NH2 (VI) que se mostrou ser mais ativo que a própia leptina e foi equipotente com o [D-Leu4]-OB3, que até então era o fragmento mais ativo descrito na literatura. Embora haja a necessidade de refinamentos, esse tipo de abordagem pode oferecer uma interessante base para o desenvolvimento de compostos correlacionados com a leptina com potencial de aplicação em estudos de obesidade humana ou na medicina veterinária. / The protein hormone produced by the ob-gene and denominated leptin, a product originating from adipose tissue, circulates in the plasma and affects the energy balance by interacting with the hypothalamus. Leptin plays an important role in the regulation of a variety of physiological functions, including food intake, body temperature and body weight maintenance. Total absence or resistance to leptin causes morbid obesity, diabetes and hypogonadism. The tertiary structure of the leptin molecule reveals the existence of a fourhelix bundle that is characteristic of the short-helix cytokines. To identify regions of the leptin molecule responsible for its bioactivity, we have synthesized six peptides based on the protein three-dimensional structure. Our results indicated that the fragments AchLEP92- 115-NH2 (IV) and Ac-[Ser117]-hLEP116-140-NH2 (V) were recognized by leptin receptor present in hp-75 cells, in agreement with the obtained by other authors, validating that this region of the molecule contain the functional epitope of the leptin molecule. In the present study, a new series of peptides encompassing the region of fragments IV and V of leptin were synthesized, and their effects on body weight and food intake were assessed when administered into the lateral cerebroventricle of normal rats. Peptides were synthesized by the solid phase methodology, purified by RP-HPLC and characterized by LC/ESI-MS. We also performed a conformational study of the peptides by circular dichroism in order to correlate the biological activity and secondary structure of the leptin fragments. Out off the new series of compounds, the best results were obtained with the fragment Ac-hLEP110-119-NH2 (VI) which showed to be more active than leptin and equipotent to [D-Leu4]-OB3 the most active leptin fragment described in the literature so far. Although the peptide fragments design needs refinement, this kind of approach may offer the basis for the development of leptin-related compounds with potential application in human obesity or veterinary medicine. / TEDE / BV UNIFESP: Teses e dissertações
136

Determinação de enantiômeros em extratos vegetais por cromatografia quiral e dicroísmo circular

Rinaldo, Daniel [UNESP] 19 March 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-03-19Bitstream added on 2014-06-13T19:05:20Z : No. of bitstreams: 1 rinaldo_d_dr_araiq.pdf: 1188120 bytes, checksum: 1e4f3603501a8b454e918390b4c81bce (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Este trabalho abordou a determinação quali e quantitativa de enantiômeros de catequinas em extratos e infusões das folhas de espécies do gênero Byrsonima (Malpighiaceae), tais como: B.basiloba, B. cocolobifolia, B. crassa, B. intermedia e B. verbascifolia. O trabalho descreve a determinação rápida e eficiente de catequina, ent- catequina, epicatequina e ent-epicatequina por cromatografia líquida de alta eficiência acoplada a detector de arranjo de fotodiodos e dicrísmo circular, usando coluna de fase estaconária quiral. O método possui alta seletividade e permite identificar inequivocadamente diastereômeros de catequinas em matrizes complexas como extratos vegetais, com limites de detecção (0,42 a 0,77 μg mL-1 ) e quantificação (1,27 a 2,32 μg mL-1 ) satisfatórios para as condições analisadas, e valores de precisão (0,3 to 4,8%) e exatidão (70,0 a 110,2%) recomendados pela ANVISA. Com exceção da espécie B. intermedia, quatro espécies do gênero apresentaram em seus extratos e infusões os diastereômeros catequina, epicatequina e ent-epicatequina. Experimentos para avaliar a epimerização da catequina indicaram que a incomum ent-epicatequina não é um artefato, podendo ser um produto do metabolismo de espécies do gênero Byrsonima. Enantiômeros da catequina apresentam diferentes atividades farmacológicas, o que pode causar a ocorrência de efeitos colaterais diversos, danosos à saúde humana. Portanto, esses resultados podem alertar quanto ao consumo indiscriminado de plantas medicinais pela população e contribuir para criação de políticas mais rigorosas no controle de qualidade de fitoterápicos no Brasil / This work deals with the qualitative and quantitative determination of catechin and epicatechin enantiomers both in extracts and infusions from the leaves of the Byrsonima (Malpighiaceae) species (B.basiloba, B. cocolobifolia, B. crassa, B. intermedia and B. verbascifolia). This work describes a simple and reliable analytical high performance liquid chromatographic (HPLC) method coupled with photodiode array detector and circular dichroism for simultaneous determination of catechin, ent-catechin, epicatechin and ent-epicatechin. The direct separation was obtained in normal phase by HPLC using chiral stationary phase. The method has high selectivity. Regardless of variations in retention time, it was possible to identify unequivocally the enantiomers of catechin and epicatechin in complex matrices like plant extracts with satisfactory limit of detection (0.42 to 0.77 μg mL-1 ) and limite of quantification (1.27 to 2.32 μg mL-1 ). Under the conditions used, precision values were 0.3 to 4.8%, whereas accuracy values were 75.0 to 110.2%, recommended by ANVISA. Aside from B. intermedia specie, the other four Byrsonima species presented catechin, epicatechin and ent-epicatechin diastereomers both in methanolic extract and infusions. Experiments were carried out for verification the possibility of catechin epimerization. It was observed that the unusual ent- epicatechin was not an artifact, but product of Byrsonima species metabolism. Enantiomers of catechin present dissimilar pharmacological activities, which may cause the occurrence of various side effects, harmful to human health. Therefore, these results may warn about the indiscriminate use of medicinal plants by the population and contribute to the quality control of Brazilian herbal medicines
137

Dicroísmo circular vibracional e eletrônico na determinação da configuração absoluta de benzopiranos de Peperomia obtusifolia e Piper gaudichaudianum (Piperaceae): implicações biológicas e biossintéticas

Batista Junior, João Marcos [UNESP] 15 February 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-02-15Bitstream added on 2014-06-13T20:26:06Z : No. of bitstreams: 1 batistajunior_jm_dr_araiq.pdf: 3011383 bytes, checksum: fd591b605558cb4d50f706b29ede19f2 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Estudos fitoquímicos visando o isolamento de benzopiranos quirais foram realizados em Peperomia obtusifolia e Piper gaudichaudianum (Piperaceae). Da espécie P. obtusifolia foram isolados dois cromanos racêmicos, a peperobtusina A e o ácido 3,4-diidro-5-hidróxi-2,7-dimetil-8-(3-metil-2-butenil)-2-(4-metil-1,3-pentadienil)-2H-1- benzopirano carboxílico, bem como oito ésteres isoméricos deste último com os monoterpenos borneol e fenchol, inéditos na literatura. P. gaudichaudianum forneceu o cromeno ácido gaudichaudiânico, também como racemato. As misturas estereoisoméricas foram resolvidas por meio de cromatografia líquida de alta eficiência quiral e os estereoisômeros purificados tiveram sua configuração absoluta determinada por comparação dos espectros experimentais de dicroísmo circular vibracional e eletrônico com aqueles preditos por cálculos mecânico-quânticos ab initio. Peperobtusina A e o ácido 3,4-diidro-5-hidróxi-2,7-dimetil-8-(3-metil-2-butenil)- 2-(4-metil-1,3-pentadienil)-2H-1-benzopirano carboxílico foram assinalados como (+)-R, enquanto o ácido gaudichaudiânico foi assinalado como (+)-S. Os ésteres de cromano com borneol foram assinalados como (−)-2S,1′′′S,2′′′R,4′′′S e (+)- 2R,1′′′S,2′′′R,4′′′S, enquanto os ésteres com fenchol foram assinalados como (−)- 2S,1′′′R,2′′′R,4′′′S e (+)-2R,1′′′R,2′′′R,4′′′S. Com a configuração absoluta assegurada, foi possível a verificação do potencial tripanocida seletivo e sinérgico para os enantiômeros do ácido gaudichaudiânico e inibidor de HIV-1 protease seletivo para o (−)-(S)-ácido 3,4-diidro-5-hidróxi-2,7-dimetil-8-(3-metil-2-butenil)-2-(4- metil-1,3-pentadienil)... / Phytochemical investigations focused on chiral benzopyrans were carried out on Peperomia obtusifolia and Piper gaudichaudianum (Piperaceae). Two racemic chromanes, peperobtusin A and 3,4-dihydro-5-hydroxy-2,7-dimethyl-8-(3-methyl-2- butenyl)-2-(4-methyl-1,3-pentadienyl)-2H-1-benzopyran carboxylic acid, as well as eight novel isomeric esters of the latter with the monoterpenes borneol and fenchol, were isolated from P. obtusifolia. P. gaudichaudianum afforded the racemic chromene gaudichaudianic acid. All stereoisomeric mixtures were resolved using chiral high performance liquid chromatography and the purified compounds had their absolute configuration determined by comparison of experimental vibrational and electronic circular dichroism spectra with those calculated using ab initio quantummechanical methods. Peperobtusin A and 3,4-dihydro-5-hydroxy-2,7-dimethyl-8-(3- methyl-2-butenyl)-2-(4-methyl-1,3-pentadienyl)-2H-1-benzopyran carboxylic acid were assigned as (+)-R, whereas gaudichaudianic acid was assigned as (+)-S. The borneol chromane esters were assigned as (−)-2S,1′′′S,2′′′R,4′′′S and (+)- 2R,1′′′S,2′′′R,4′′′S, while the fenchol esters were assigned as (−)-2S,1′′′R,2′′′R,4′′′S e (+)-2R,1′′′R,2′′′R,4′′′S. Once the absolute configuration had been established it was possible to identify a selective and synergistic trypanocidal activity for the enantiomers of gaudichaudianic acid as well as a selective HIV-1 protease inhibitory potential for (−)-(S)-3,4-dihydro-5-hydroxy-2,7-dimethyl-8-(3-methyl-2-butenyl)-2-(4- methyl-1,3-pentadienyl)... (Complete abstract click electronic access below)
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CIRCULAR ECONOMY NOW00 : How can a tool stimulate Circular Economy whereby the product development stage will be guided towards less waste generation?

Leroy, Luisa January 2018 (has links)
The government has made a choice to call a halt to climate change and has defined concrete milestones that everyone can use in practical terms, but the practical and knowledge side is still lacking within society. There is still no unambiguous approach for circular economy. Unfortunately, no manual is ready yet to take the steps towards 2050. The best advice to give is to start with awareness: making known to the general public. This step is a first step towards 100% circular economy. The greatest effect of circularity of a product must be realized in the design phase. Aspects such as maintenance, flexibility in use and adaptability, disassembly possibilities and the usability at end of life is determined by the design. The choice of materials what a product consists of is also important here. For this, the researcher sought a solution that supports these two important pillars. Circularity is a complex subject and there is a need to convert this complex language whereby this language becomes more intelligible to the daily users, architects, designers and product developers. Making circularity measurable, on the basis of product information from the supplier, the tool calculates the degree of circularity. The focus of the tool lies in the calculation of the impact of its materials and the amount of waste generated during the entire journey of the product. The results of the tool is named PICI© and can be compared with the certification techniques of today, except this one is circular-proof, while almost all of the certifications has been developed within a linear economy. Today's certificates will have to make room for the circularity certificates of the future. In addition, this study will also provide a direction for a circular methodology that will fully support the transition towards a circular service or product development. This research has the aim to make manufacturers, designers, architects or product developers aware what the impact of their product is, whereby the material-decision-making process will be striving for a fully circular  products and the re-use of the those materials.  This tool can motivate and make this impact of waste more visible. On top of that, this tool has a special focus on urban and architectural lighting, due to the collaboration with Spectrum advice and Design, in the Netherlands. Therefore, a case study is included within this study from Hydro Aluminum who supported this research with real-end data.
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Exploring a Web of Carriers Promoting the Travel of an Idea : the Case of a Circular Fashion System

Rudberg, Isabel, Ottow, Frida January 2018 (has links)
In previous research, attention is given to the travel and translation of ideas in order to capture how ideas flow and by whom. External actors, so called carriers, promote certain ideas and discard others, further playing a significant part in the institutionalization of ideas. The multitude of different carriers, their different promotion techniques and interconnectedness call for the need to study them in relation and differentiation to one another. Through a qualitative content analysis of documents, interviews and videos, we present a case study on carriers promoting the current idea of a circular fashion system. The investigated carriers are consultants, media, academia, NGO/NPOs and gurus. Alongside the previously identified sequential and parallel modes of translation, we find carriers promoting the travel of an idea jointly. Among the carriers studied, the findings reveal evidence of (1) linkages through cross-referencing, and (2) collaboration through funding, assignment and co-writing. Coupling the notion of blurred boundaries between carriers with ecologies of translation, the study finds carriers situating in different contexts and constellations, forming hybrids and hierarchies. Providing such evidence of a more complex scenery, we argue that the landscape in which carriers promote an idea is best understood as constituting webs.
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Amplia??o de movimentos na dan?a circular com pessoas com defici?ncia visual

Romao, Telma Sampaio 09 September 2011 (has links)
Made available in DSpace on 2014-12-17T14:00:15Z (GMT). No. of bitstreams: 1 TelmaSR_DISSERT.pdf: 1038202 bytes, checksum: bdf7d86bb7d4772e1a0285aaac29d84a (MD5) Previous issue date: 2011-09-09 / This paper aims at studying how circular dance can afford to sight-disabled peoples movement and how they can learn to cope with the deep movement of relation, consciousness, appropriation and communion with the world. Inside circular dance, a cosmic metaphor, is inscribed the movement of the world, which tells and changes amorously the human history. In the works of Paulo Freire and Maurice Merleau-Ponty one can find the necessary support to discuss, as long as possible, movement and existence. Research-action is used as a methodological approach whose empirical center is placed on the Institute of Education and Rehabilitation of Blind, in Natal, which shelters eight sightdisabled adults. The research s data reveal that the practice of circular dance concurs to enlarge the movement of the research s subjects, to develop a more accurate perception of their selves and of their own capacities, as well as improve the relations Me/Others, Me/World, which require a context of differences. The study has revealed that the practice of dance develops a better perception of the limits and surpasses as a human condition and, in consequence, the discovery of one s own body and the other s body as a resource of lessons and representations of the self and of the world. It lets out the development of a new way of thinking and coping with discrimination surrounding the disabled persons. In movement, in circular dance, the barrier between sight disablement and vision loses force. / O referido estudo tem como objetivo investigar de que maneira a dan?a circular contribui para amplia??o do movimento de pessoas com defici?ncia visual no contexto em que se inserem e, portanto, aprendem a lidar com o movimento intenso de rela??o, de consci?ncia, de apropria??o e comunh?o com o mundo. Na dan?a circular, met?fora c?smica, est? presente o movimento do mundo que conta e transforma, de forma amorosa, a hist?ria da humanidade. Em Paulo Freire e Maurice Merleau-Ponty encontra-se o suporte necess?rio para discutir, tanto quanto poss?vel, movimento e exist?ncia. A pesquisa-a??o ? assumida como enfoque metodol?gico, tendo como campo emp?rico o Instituto de Educa??o e Reabilita??o de Cegos de Natal, envolvendo, diretamente, oito pessoas com defici?ncia visual. Os resultados da pesquisa mostram que a pr?tica da dan?a circular tem influ?ncia na amplia??o do movimento dos sujeitos da pesquisa, no desenvolvimento de uma melhor percep??o de si, e das suas capacidades, nas rela??es Eu/Outro, Eu/Mundo, as quais se d?o num contexto de diferen?as. A pesquisa tamb?m constata que a pr?tica da dan?a ? fomentadora do encontro que possibilita a compreens?o das limita??es e supera??es como uma quest?o humana e, neste encontro da dan?a, a descoberta do pr?prio corpo e do corpo do outro, como fonte de ensinamentos e representa??o de si mesmo e do mundo. Demonstra tamb?m desenvolvimento de um novo modo de pensar e agir sobre o quadro discriminat?rio que a pessoa com defici?ncia visual vive. No movimento, na dan?a circular, o divisor existente entre a defici?ncia visual e vid?ncia perde a for?a.

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