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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

Síntese de nanopartículas de ouro para amplificação do espalhamento Raman (SERS) e da fluorescência (SEF) visando aplicações sensoriais / Synthesis of gold nanoparticles for enhancement of Raman scattering (SERS) and fluorescence (SEF) targeting sensory applications

Camacho, Sabrina Aléssio 24 January 2018 (has links)
Submitted by Sabrina Alessio Camacho null (sabrina.alessio@gmail.com) on 2018-02-28T15:16:28Z No. of bitstreams: 1 Tese_Sabrina Alessio Camacho.pdf: 5079527 bytes, checksum: 10f4f3ced26424a88ddd35b29e074c25 (MD5) / Approved for entry into archive by Maria Marlene Zaniboni null (zaniboni@bauru.unesp.br) on 2018-02-28T18:45:55Z (GMT) No. of bitstreams: 1 camacho_sa_dr_bauru.pdf: 5079527 bytes, checksum: 10f4f3ced26424a88ddd35b29e074c25 (MD5) / Made available in DSpace on 2018-02-28T18:45:56Z (GMT). No. of bitstreams: 1 camacho_sa_dr_bauru.pdf: 5079527 bytes, checksum: 10f4f3ced26424a88ddd35b29e074c25 (MD5) Previous issue date: 2018-01-24 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O presente trabalho abrange a síntese de nanopartículas metálicas com propriedades plasmônicas específicas incorporadas a filmes finos nanoestruturados de moléculas de interesse, como metaloporfirinas e outras. Nanopartículas de ouro (AuNPs 16 nm) foram incorporadas a filmes Langmuir-Blodgett (LB) de metaloporfirina visando o efeito SERS (espalhamento Raman amplificado em superfície). A incorporação das AuNPs se deu por codeposição, a partir das interações entre as AuNPs (presentes na subfase do filme de Langmuir) e as moléculas de metaloporfirina (espalhadas na interface ar/água). Nanopartículas de ouro recobertas com sílica (Au-SHINs), com tamanhos diferentes (40 e 100 nm) e mesma espessura de recobrimento (10 nm), também foram incorporadas em filmes LB e em solução aquosa visando o efeito SEF (fluorescência amplificada em superfície). Três variáveis foram aplicadas para aumentar a fluorescência: tamanho de nanopartícula, agregação e temperatura da amostra. Resultados teóricos e experimentais mostraram que as Au-SHINs 100 nm apresentam uma intensidade de amplificação cerca de 3 vezes maior e um espalhamento 2 ordens de grandeza maior que as Au-SHINs 40 nm, levando a maiores fatores de amplificação (EF). Além disso, a agregação das Au-SHINs com eletrólito e a diminuição da temperatura da amostra também resultou em maiores EF. Visando uma aplicação ambiental, AuNPs 100 nm e Au-SHINs 100 nm recobertas com 4 nm de sílica foram aplicadas na detecção do herbicida ametrina. Soluções etanólicas com concentração de 10-5 mol/L em coloides de AuNPs e Au-SHINs foram detectadas via SERS. Já em cana-de-açúcar, a detecção foi possível somente com AuNPs, porém, com concentrações no intervalo de 10-4 a 10-8 mol/L, sendo 5,3 x 10-8 mol/L o limite máximo de resíduos de ametrina permitido em produtos agrícolas. Visando uma aplicação biológica, Au-SHINs 100 nm recobertas com 10 e 4 nm de sílica foram utilizadas na fabricação de SEF e SERS tags, respectivamente, para detecção dos antígenos IgM e do vírus da Zika em plataformas de imunoensaio. Os limites de detecção alcançados foram de 5,0 e 12,5 ng/mL para os antígenos IgM e Zika, respectivamente. Neste último caso foi possível a distinção com antígenos da Dengue, evitando a reatividade cruzada, um entrave freqüentemente encontrado em ensaios de diagnóstico da Zika. / The present work covers the synthesis of metallic nanoparticles with specific plasmonic properties incorporated into nanostructured thin films of target molecules, as metalloporphyrins and others. Gold nanoparticles (AuNPs 16 nm) were incorporated into Langmuir-Blodgett (LB) films of metalloporphyrin aiming the SERS effect (surface-enhanced Raman spectroscopy). AuNPs were incorporated by co-deposition, taking advantage of the interaction between the AuNPs (in the Langmuir film subphase) and the metalloporphyrin molecules (sprayed at the air/water interface). Gold shell-isolated nanoparticles (Au-SHINs), with different sizes (40 and 100 nm) and same silica shell thickness (10 nm), were also incorporated into LB films and in aqueous solution targeting the SEF effect (surface-enhanced fluorescence). Three variables were applied to increase the fluorescence: size of nanoparticle, aggregation and sample temperature. Theoretical and experimental results showed that the Au-SHINs 100 nm have an enhancement intensity about 3 times higher and a scattering 2 orders of magnitude higher than the Au-SHINs 40 nm, leading to higher enhancement factors (EF). Besides, the aggregation of Au-SHINs with electrolyte and the sample temperature decreased also resulted to higher EF. Aiming an environmental application, AuNPs 100 nm and Au-SHINs 100 nm coated with 4 nm of silica were applied to detect the herbicide ametryn. Ethanolic solution with concentration of 10-5 mol/L in AuNPs and Au-SHINs colloids were detected via SERS. While in sugar cane, the detection was only possible with AuNPs, however, with concentrations at the range from 10-4 to 10-8 mol/L, being 5.3 x 10-8 mol/L the maximum residual limit of ametryn allowed in agricultural products. Aiming a biological application, Au-SHINs 100 nm coated with 10 and 4 nm of silica were used in the development of SEF and SERS tags, respectively, for detecting IgM and Zika virus antigens on immunoassay platforms. The limits of detection were 5.0 and 12.5 ng/mL for IgM and Zika antigens, respectively. In the latter, it was possible the distinction with Dengue antigens, preventing the cross-reactivity, an obstacle frequently found in diagnostic assays of Zika. / 2013/01897-4
2

South Sudan's secession in contemporary Africa

Nicholson, Marietjie Johanna 22 October 2013 (has links)
The Republic of South Sudan’s independence on 9 July 2011 revived the possibility of secession as means of self-determination. The purpose of this exploratory study was to analyse and assess the implication of secession on the African environment, with reference to South Sudan. The qualitative research approach enabled the researcher to draw parallels between literature and opinions of experts involved in South Sudan’s secession. Driving the secessionist approach are ideologies and greed of elites and peoples in power, religious differences and the unequal distribution of wealth and resources that exacerbate tensions between the fortunate peoples enjoying opportunities to develop and the excluded, utterly poor peoples just surviving. National and international attitudes sanction or veto the possibility to secede. Although secession could terminate continued disarray, it should only be considered if both states, as parties to the secession, could ensure the delivery of statehood responsibilities to their citizens and neighbouring communities.
3

Characterization of PVA hydrogels with regards to vascular graft development

Elshazly, Tarek Hassan 12 April 2004 (has links)
PVA hydrogels are potential biomaterials for various tissue-engineering applications. PVA hydrogels are relevant to vascular graft development due to their excellent biocompatibility and the capability to possess a wide range of mechanical properties based on compositional and processing parameters. This thesis aims to characterize some PVA hydrogels mechanically, biologically, and physically. A constitutive formulation is used for mechanical characterization, which allows for analysis of any possible stress-strain configuration applied to the material. A bovine aortic endothelial cell adhesion study under physiologic blood flow conditions comprises the biologic characterization, which gives insight into how human endothelial cells might interact with PVA hydrogels in a vascular graft application. A high-resolution SEM study is used to physically characterize the material, which furthers the understanding of the reactions of this material in vivo. These characterizations of PVA hydrogels will aid in the development of tissue-engineered products, in particular, the potential use as a vascular grafting biomaterial.
4

The study of the ERP system implemented by the major steel mill in Mainland China ¡VA case study on Wuhan Iron & steel Co.

Wu, Tsung-Chi 31 July 2005 (has links)
The Study of the ERP system implemented by the major steel mills in mainland China - a case study on Wuhan Iron & Steel Co. Since 1990s, the radical change of customer demand, short life cycle of products, and accelerating innovation of technology have driven the enterprises to carry on reform of the management style and renewal of the management skill. The reform of the management style is focused on BPR (Business Process Re-engineering), and the renewal of management is to implement ERP (Enterprise Resources Planning) system. It is generally recognized that information technology can upgrade the enterprise competence. Applying information technology on BPR to facilitate ERP implementation is also proved to be successful. Both of them are important elements to improve business management. This research employs empirical studies about the implementation of ERP in large steel mills. Being different from the traditional manufacturing industries, the production type of large steel mills is a pyramid-shape model with higher difficulty, more financial and resource inputs. There are four different implementation modules based on the cases studied in this research: 1. Start from the rationalization of business administration, and self-develop a proper ERP system; 2. Look for assistance from the experienced intra-industry companies, and collaborative-develop a system required; 3. Look for assistance from the consultant companies to integrate the package software; and 4. Look for assistance from the software companies with domain knowledge in the early period, and start self-developing in the late period. All the implementing methodology, organization structure and principles of the four modules are described in this article. It is also our hope that the research result can help the enterprises to build up ERP.
5

Shame, Admiration, and Self-Esteem

Clearly@iprimus.com.au, Colin Earl January 2006 (has links)
This thesis is an exploration of the shame that inheres in not being able to self-admire. I call this incapacity to admire oneself ontological shame, and I argue that it is the source of the masquerades, concealments and negative emotions that surround the pursuit and defence of a self-esteem founded on an impoverished form of pride. I argue that there is a radical asymmetry between our admiration and esteem for others and how we evaluate our own sense of self-worth. Where admiration at its highest pitch is the wonderful agape experience of apprehending preciousness in others, our own sense of self-worth is limited to experiences of pride and other forms of self-affirmation; none of which allow us the joy of seeing ourselves as wonders in the world. Because we can admire and want to be admired, not being able to self-admire amounts to a limitation of a sort which carries with it a primordial resentment against life itself. It is largely how we respond to our ontological limitation and to our resentment that determines the positive or negative manner in which we interact with others, and whether or not we are likely to have an envious or humble disposition. In the first three chapters I lay the groundwork for the main argument of the thesis by highlighting the difficulties self-esteem theorists have in agreeing upon the value of ‘high’ self-esteem, introduce the relation between self-esteem and shame, argue for a distinction between self-esteem and public esteem, and provide an account of the gift-exchange nature of admiration which explains why we cannot self-admire. In the central chapters I focus on shame; on acts of concealment that can be either appropriate covering for, or deceitful denial of our ontological limitation; how self-worth is created through a reconciliation to shame, and why the ‘self-act dissociation’ theories of guilt fail to capture the shame attached to ‘being guilty’ of a wrongdoing. In Chapters Seven and Eight I examine envy, first in how it can be disguised as moral resentment; how it differs to admiration in its role in emulation, and finally how as a disposition it stands in stark contrast to humility. It is in humility that we grasp the benefits associated with our own incapacity to self-admire through our need to interact and exchange gifts with others.
6

Corporate Social Responsibility within Swedish elite football organizations : A qualitative study regarding the CSR work of organizations within Swedish elite football

Johansson, Alexander, Löfstedt, Jakob January 2020 (has links)
Corporate Social responsibility is a term that has received more attention in the world of business in past years. Today, an elite Swedish football organization can be compared to a small or medium sized business. This implies that CSR is becoming a more important term in the football line of business as well. Football engage people all over the world in a unique way that bring people together. It doesn't matter which part of the world you come from, your background, culture or language. Everyone speak the common language that is football. The CSR work of Swedish football organizations is therefore a very important part of society. This since these organization can affect individuals on a daily basis and help them to make good choices in life. The purpose of this Bachelor’s thesis in Business Administration was to investigate how Swedish elite football organizations work with CSR. Partly to demonstrate how important the function of football organizations in society is, but also to investigate and show that through CSR football organizations can achieve goals and values that the organizations are built upon and to investigate whether CSR can lead to competitive advantages that can benefit the organization as a whole. This research study was performed by case studies were four Swedish elite football organizations participated. The study was conducted with qualitative interviews with carefully selected respondents from the different organizations. The results of the study both changed our approach to CSR and gave us a greater understanding of how Swedish football clubs work and view CSR.
7

Otimização e caracterização de nanoestruturas de ouro e prata recobertas com uma camada ultrafina de MnO2, SiO2 ou TiO2: uma alternativa para aplicações das técnicas espectroscópicas intensificadas por superfície

Marques, Flávia Campos 26 July 2018 (has links)
Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-09-20T12:04:51Z No. of bitstreams: 1 flaviacamposmarques.pdf: 5444687 bytes, checksum: ee4ddf83c1895a69c8df07fd21fede21 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-10-01T19:24:51Z (GMT) No. of bitstreams: 1 flaviacamposmarques.pdf: 5444687 bytes, checksum: ee4ddf83c1895a69c8df07fd21fede21 (MD5) / Made available in DSpace on 2018-10-01T19:24:51Z (GMT). No. of bitstreams: 1 flaviacamposmarques.pdf: 5444687 bytes, checksum: ee4ddf83c1895a69c8df07fd21fede21 (MD5) Previous issue date: 2018-07-26 / O presente trabalho abrange as sínteses e caracterizações nanobastões de ouro (AuNB) e nanopartículas esféricas de ouro e prata (AuNE e AgNE) recobertos por uma camada ultrafina de óxido de manganês, silício ou titânio. Utilizaram-se para caracterização das camadas dielétricas as técnicas UV-VIS, espectroscopia de absorção no infravermelho, difração raio X (XRD), voltametria cíclica (CV) e microscopia eletrônica de transmissão (TEM). As nanoestruturas plasmônicas (NP) utilizadas como substratos nas aplicações espectroscópicas são instável na presença de muitos analitos, o que pode levar à agregação e posteriormente à precipitação do material, inviabilizando a caracterização do adsorbato. O recobrimento das NP por camadas dielétricas aumenta fortemente a sua estabilidade estrutural, conservando suas propriedades plasmônicas. Nesse intuito, o escopo desse trabalho visou recobrir os AuNB por MnO2, SiO2 ou TiO2 e AuNE ou AgNE por TiO2 e verificar a sua aplicabilidade nas técnicas espectroscópicas de superfície. Por meio do deslocamento da banda de ressonância de plasmon de superfície localizado foi possível acompanhar a formação e o aumento da espessura da camada dielétrica adsorvida na interface do metal quando comparados às NP sem recobrimento, que são resultados das mudanças no índice de refração local às NP. A técnica de XRD foi utilizada para confirmar a formação dos materiais híbridos; por essa técnica foram observados halo não-cristalinos atribuídos aos óxidos e picos de difração característicos de nanoestruturas metálicas de Au. Além disso, foi possível caracterizar as NP de Au e Ag com os óxidos por meio da análise por TEM, em que foram observados recobrimentos uniformes das camadas de MnO2, SiO2 ou TiO2 envolvendo o núcleo metálico com espessuras inferiores a 6 nm. O uso da técnica de CV permitiu verificar que as cascas de óxidos não apresentaram orifícios. Os materiais híbridos otimizados foram utilizados como substratos espalhamento Raman intensificado por superfície (SERS) e fluorescência intensificada por superfície (SEF) para análise de adsorção da molécula IR-820. As medidas SERS utilizando as radiações incidentes 633 e 1064 nm mostraram um aumento significativo nas intensidades relativas de alguns modos vibracionais comparado ao espectro Raman da molécula livre, através dos quais foram realizadas as atribuições dos modos vibracionais. Já as medidas SEF obtidas com a radiação incidente 785 nm, observou-se um aumento da intensidade SEF para espessuras maiores de óxido, atribuídas ao aumento da distância entre adsorbato e a superfície condutora do metal. Além disso, foi estudada por SERS a adsorção de ácido 3-mercaptopropiônico (HMP) e ácido 4-mercaptobenzoico (HMB) nessas NP recobertas, e através dos resultados foram atribuídos os modos vibracionais mais significativos. Através dessas atribuições foi possível verificar o sitio de adsorção e a orientação das moléculas HMP e HMB. Os resultados obtidos confirmaram a formação da camada de óxido envolvendo o núcleo metálico. Além disso, as aplicações dos efeitos SERS e SEF mostraram-se bastante promissoras para os substratos sintetizados. / The present work covers the syntheses and characterizations of gold nanorods (AuNR) and gold and silver spherical nanoparticles (AuSN and AgSN) coated with ultrathin layers of manganese, silicon or titanium oxide. Dielectric layers were characterized by UV-Vis, infrared absorption spectroscopy, X ray diffraction (XRD), cyclic voltammetry (CV) and transmission electron microscopy (TEM) techniques. Plasmonic nanostructures (PN) which are used as substrates in spectroscopic applications are unstable in the presence of many analytes, thus leading to aggregation and subsequent precipitation. This instability makes the characterization of the adsorbate much more challenging. Coating PN with dielectric layers strongly increases its structural stability, while retaining their plasmonic properties. To this end, the scope of this work was to cover AuNR by ultrathin layers of MnO2, SiO2 or TiO2 and AuNS or AgNS by TiO2 and verify its applicability in surface spectroscopic techniques. By means of displacement of the localized surface plasmon resonance band, it was possible to follow the formation and increase of the thickness of the dielectric layer adsorbed at the interface of the metal when compared to PN without coating, which are results of the changes in the local refractive index to PN. The XRD technique was used to confirm the formation of the hybrid materials. It was observed non-crystalline haloes attributed to the oxides and diffraction peaks characteristic of Au metallic nanostructures. Moreover, it was possible to characterize the Ag and Au PN with oxides by means of analysis by TEM, wherein was possible to confirm the presence of uniform layer coatings of MnO2, SiO2 or TiO2 surrounding the metallic core with a thickness below 6 nm. The use of the CV technique allowed verifying that the oxide shells did not have pinholes. The optimized hybrid materials were used as surface enhanced Raman scattering (SERS) and surface enhanced fluorescence (SEF) substrates for adsorption analysis of the IR-820 molecule. The SERS measurements using incident radiations at 633 and 1064 nm showed a significant increase in the relative intensities of some vibrational modes compared to the Raman spectrum of the free molecule, through which the assignments of the vibrational modes were performed. The SEF measurements obtained with the incident radiation 785 nm showed an increase in the SEF intensity for higher oxide thicknesses, which was attributed to the increase in the distance between adsorbate and the conductive surface of the metal. Moreover, adsorption of the 3-mercaptopropionic acid (MPA) and 4-mercaptobenzoic acid (MBA) molecules in these NP coated was studied using SERS. It was possible to identify and assign the most significant vibrational modes and confirm the adsorption site of MPA and MBA molecules. The results confirmed the successful formation of the oxide layers surrounding the metallic cores. Finally, the applications of the SERS and SEF effect have shown to be very promising for the synthesized substrates.
8

Síntese e caracterizações estruturais e espectroscópicas de vidros e vitrocerâmicas contendo partículas metálicas usando óxido de antimônio (III) como agente redutor

Franco, Douglas Faza 30 August 2015 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-01-04T10:48:31Z No. of bitstreams: 1 douglasfazafranco.pdf: 6741495 bytes, checksum: 49d756dd3eff71da15e32191ca4e5a08 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-01-25T15:36:09Z (GMT) No. of bitstreams: 1 douglasfazafranco.pdf: 6741495 bytes, checksum: 49d756dd3eff71da15e32191ca4e5a08 (MD5) / Made available in DSpace on 2016-01-25T15:36:09Z (GMT). No. of bitstreams: 1 douglasfazafranco.pdf: 6741495 bytes, checksum: 49d756dd3eff71da15e32191ca4e5a08 (MD5) Previous issue date: 2015-08-30 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O presente trabalho trata da preparação de vidros baseados em polifosfatos de sódio (NaPO3)n contendo óxidos de antimônio (III) e cobre (II), onde a presença do agente redutor α-Sb2O3 foi responsável pelos processos de oxi-redução: Cu2+→ Cu+→Cu0 durante a síntese dos vidros a 1000°C. Os resultados de medidas de absorção de Raios X próxima a borda K do Cu (XANES) e de espectroscopia Eletrônica forneceram informações valiosas sobre a existência de partículas metálicas nos vidros com dimensões nanométricas. Este resultado mostra a possibilidade de se obter nanopartículas metálicas de Cu0 durante a etapa de fusão dos vidros sem a necessidade de tratamentos térmicos dos materiais em temperaturas próximas a transição vítrea. A síntese de diferentes fases cristalinas do óxido de antimônio (III): α-Sb2O3, α-Sb2O4, β-Sb2O4 e β-Sb2O3, por meio de diferentes tratamentos isotérmicos possibilitou o estudo via espectroscopia Raman e Difração de Raios X por policristais destes compostos. O diagrama de composição ternário para os vidros (0,9-x)NaPO3-xSb2O3-0,1CuO mostra as diferentes regiões de domínio vítreo de formação de vidros estáveis. O estudo espectroscópico dos vidros (0,9-x)NaPO3-xSb2O3-0,1CuO contendo nanopartículas metálicas de Cu0 dopados com 0,5 mol% de Er2O3 foi realizado via espectroscopia de Fluorescência usando diferentes radiações excitantes: 532, 633 e 785 nm. O mapeamento Raman dos vidros mostrou a intensificação da fluorescência dos íons Er3+, tanto pelo efeito da mudança do ambiente químico ao redor do íon Er3+ (cristalização) quanto pela transferência de energia dos plasmons de superfície excitados para os níveis de energia do íon terra-rara (SEF – Surface-Enhanced Fluorescence). Além disso, vidros contendo nanopartículas metálicas de Cu0 apresentaram resultados satisfatórios quando a possibilidade de utilização como substratos SERS (Surface-Enhanced Resonance Spectroscopy), sendo observada a intensificação do sinal Raman dos modos vibracionais da o-fenilenodiamina usando o vidro x = 0,6 como substrato. / This Thesis deals with the preparation of glasses based on sodium polyphosphate, containing antimony (III) and copper (II) oxides. The presence of α-Sb2O3 reducing agent was responsible for redox processes: Cu 2+→ Cu+→ Cu0 during synthesis of the glasses at 1000°C. The results of X-ray absorption measurements near the K edge of Cu (XANES) and electronic spectroscopy provided valuable information on the presence of metallic particles in glasses with nanometric dimensions. This result shows the possibility of obtaining metallic Cu nanoparticles during the melting step of glass preparation, without the need for posterior treatments. The synthesis of the different crystal phases of antimony (III) oxide, i.e., α-Sb2O3, α-Sb2O4, β-Sb2O4 and β-Sb2O3, through different isothermal treatments enabled the study through Raman spectroscopy and X-ray Diffraction. The ternary composition diagram for glass NaPO3-Sb2O3-CuO shows the different regions of vitreous domain. The spectroscopic study of glasses (0.9-x)NaPO3- xSb2O3-0,1CuO, containing Cu nanoparticles doped with 0.5 mol% of Er2O3 was realized by fluorescence spectroscopy using different exciting radiation: 532, 633 and 785 nm. The Raman mapping of these glasses showed the intensification of fluorescence of Er3+ ions, both the effect of changing the chemical environment around the Er3+ ion (crystallization) as the energy transfer from the excited surface plasmons for energy rare-earth ion levels (SEF - Surface-Enhanced Fluorescence). Additionally, glasses containing Cu nanoparticles showed satisfactory results of use as SERS substrates (Surface-Enhanced Resonance Spectroscopy), with the observed enhancement of the Raman signal of the vibrational modes of using phenylenediamine and the glass with x = 0.6 as substrate.
9

Síntese e caracterização de nanobastões e nanobipirâmides de Au para aplicação em biossensores plasmônicos

Peixoto, Linus Pauling de Faria 21 August 2015 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-01-04T11:25:56Z No. of bitstreams: 1 linuspaulingdefariapeixoto.pdf: 3833578 bytes, checksum: 7044b2daa711546991179b32265a99dc (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-01-25T15:38:14Z (GMT) No. of bitstreams: 1 linuspaulingdefariapeixoto.pdf: 3833578 bytes, checksum: 7044b2daa711546991179b32265a99dc (MD5) / Made available in DSpace on 2016-01-25T15:38:14Z (GMT). No. of bitstreams: 1 linuspaulingdefariapeixoto.pdf: 3833578 bytes, checksum: 7044b2daa711546991179b32265a99dc (MD5) Previous issue date: 2015-08-21 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O presente trabalho visou a síntese e caracterização de nanopartículas de ouro (AuNPs) e sua aplicação na construção de biossensores plasmônicos utilizando para a detecção as técnicas de LSPR (ressonância de plasmon de superfície localizado) e SERS/SEF (espalhamento Raman intensificado por superfície / fluorescência intensificada por superfície). As AuNPs foram sintetizadas na forma de nanobastões (AuNRs) e nanobipirâmides (AuNBs) utilizando o método de crescimento por partículas precursoras (seed) e utilizando surfactantes para direcionamento do crescimento das mesmas. Devido ao melhor rendimento obtido para AuNRs, avaliou-se apenas sua sensibilidade em suspensão ou imobilizadas em lâminas de vidro. Para a imobilização em vidro, o 3-mercaptopropiltrimetoxisilano foi utilizado como molécula ligante entre o vidro e as AuNPs e posteriormente os substratos modificados foram caracterizados por espectroscopia UV-VIS, microscopia eletrônica de varredura e voltametria cíclica. A superfície dos AuNRs foi modificada para a detecção de duas biomoléculas-prova: (1) estreptavidina, realizada pelo mecanismo de interação por bioafinidade com a biotina, utilizando cisteamina como ligante entre as AuNPs e a biotina; (2) anti-BSA, através do mecanismo de interação antígeno-anticorpo, ativando a superfície das AuNPs (previamente modificada com ácido mercaptoundecanóico) com N-(3-dimetilaminopropil)-N′-etilcarbodiimida e N-hidroxisuccinimida. A sensibilidade LSPR foi monitorada pelo deslocamento do máximo da banda do plasmon longitudinal dos AuNRs frente ao aumento do índice de refração local devido às modificações na superfície dos AuNRs, alcançando 297 nm RIU-1. A detecção por SERS foi realizada através do modo extrínseco, utilizando um corante (IR-820) como molécula marcadora sobre a superfície dos AuNRs. Os biossensores construídos tiveram desempenho satisfatório na detecção de moléculas provas, além de boa sensibilidade frente a modificações no índice de refração do meio; isso foi observado tanto para AuNPs em suspensão ou imobilizadas em lâminas de vidro. Os procedimentos reportados são simples, rápidos e eficientes para a aplicação em biossensores. Adicionalmente, a integração das AuNPs em suspensão (modificadas com moléculas marcadoras) com as AuNPs imobilizadas nas lâminas de vidro, se mostrou um método interessante para a detecção de biomoléculas utilizando SERS/SEF. / This work was focused on the synthesis and characterization of gold nanoparticles (AuNPs) for applying as LSPR (localized surface plasmon resonance) and SERS/SEF (surface enhanced Raman spectroscopy / surface enhanced fluorescence) based biosensors. AuNPs were synthesized in two different forms, nanorods (AuNRs) and nanobipyramids (AuNBs), controlling the growth of seeds by using surfactants. A better yield was obtained to AuNRs and therefore, only the sensitivity of these nanoparticles was evaluated either using the AuNRs in suspension or immobilized on glass slides. A monolayer of 3-mercaptopropylmetoxisilane was used as a linker between AuNPs and glass surface, and after the modified glass slides were characterized with UV-VIS spectroscopy, scanning electronic microscopy and cyclic voltammetry. AuNRs surface was modified aiming the detection of two probe molecules: (1) streptavidin allowed by the bioafinity for biotin, using cysteamine as monolayer between AuNPs and biotin; (2) anti-BSA allowed by an antigen-antibody interaction activating the surface (previously modified with mercaptoundecanoic acid) with N-(3-dimetilaminopropil)-N′-etilcarbodiimide and N-hidroxisuccinimide. The LSPR sensitivity was evaluated by monitoring shifts in the longitudinal plasmon mode of AuNRs with changes in local refractive index due to surface binding events, reaching 297 nm RIU-1. SERS sensitivity was carried out in an extrinsic mode using a dye (IR-820) as SERS label on AuNRs surface. The biosensors developed in this work (AuNPs in suspension and adsorbed on glass slides) are efficient as biosensor as they presented good sensitivity for change in refractive index and for surface binding with probe molecules. The main advantages of these biosensors is the simple methodology summed to the short time of analysis. In addition, coupling the labeled AuNPs in suspension with the AuNPs adsorbed on glass slides is an interesting methodology for SERS/SEF detection of biomolecules.
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Svenska herrelitfotbollsspelares karriärupplevelser och resor till elitfotbollen efter att de blivit bortselekterade från seniorkontrakt som juniorer / Football players in swedish mens elite club’s career experiencesand journeys to elite football after being de-selected from senior contract as junior academyplayers

Perem, Filip January 2023 (has links)
Majoriteten av alla akademifotbollsspelare i Sverige idag blir nekade ett seniorkontraktoch får därmed söka sig till ett nytt lag. Ett sådant besked är tufft att få, men behöver inte betydaatt eliten inte kan nås genom alternativa vägar utanför eliten. Därav är syftet med denna studie attundersöka svenska herrelitfotbollsspelares karriärupplevelser och resor till elitfotbollen efter attde blivit bortselekterade från seniorkontrakt som juniorer. Denna studie undersökerupplevelserna hos sju manliga fotbollsspelare som idag spelar i Superettan eller Allsvenskan.Genom arbete som bestått av intervjuer och reflexiv tematisk analys har två tematiska kartorutifrån respektive frågeställning tagits fram. Den första kartan hänvisar till tiden från attinformanterna blivit bortselekterade till att de fått sin första kontakt med elitfotbollen ochinnefattar två huvudteman, medan den andra kartan berör tiden från den första kontakten medelitfotbollen och framåt vilket innefattar tre huvudteman. Samtliga övergripande teman följer enkronologisk ordning och redogör bland annat för erfarenheter såsom utmaningar, resurser ochstrategier. Vidare anses fortsatt forskning inom området i form av att studera idrottaresupplevelser av en bortselektering vara av värde. / Today, the majority of all academy football players in Sweden become rejected to receivea senior contract and are thus forced to find a new team. Such a message is tough to receive butdoes not have to mean that the elite is not reachable through alternative paths outside of the elite.Therefore, the aim of this study is to examine Football players in swedish mens elite club’scareer experiences and journeys to elite football after being de-selected from senior contract asjunior academy players. Present study reviewed the experiences from seven male football playerswho are currently playing in Superettan or Allsvenskan. Through the process containing ofinterviews two reflexive thematic analyzes were created grounded in each of two main researchquestions. three overall themes are created: The first thematic analysis aimed touched the periodfrom when the informants were deselected from their junior academy clubs to when the firstcontact with senior elite football took place. The second one aimed towards the period fromwhen the first contact took place and forward. These overall themes are presented inchronological order and cover experiences as, for example, challenges, resources, and strategies.Lastly, further investigations in the area in terms of studying athletes’ experiences of beingrejected to receive a senior contract, is claimed to of value.

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