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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.
61

Springback Calibration of Sheet Metal Components Using Impulse Forming Methods

Woodward, Steven T. 27 July 2011 (has links)
No description available.
62

Hur påverkas svenskhushållskonsumtion av olikabindningstider på bolån vidstyrränteförändringar?

Wejdenmark, Martin, Rasooli, Alireza January 2024 (has links)
In Sweden variable-rate mortgages are relatively common. Furthermore, householdindebtedness is high in relation to other nations within the European Union. Therefore,monetary policy has a stronger effect on the economy due to the household sensitivityregarding interest rates. During times of changes in the policy rate, the expectation is that theimpact on consumption is greater, because of a stronger effect due to higher sensitivity of theinterest rates. Moreover, consumption expenditures make up a large part of the Swedisheconomy, with approximately half of the gross domestic product consisting of householdconsumption. Because of the mentioned reasons it is important and compelling to examinethe relationship between the structure of the mortgage market, monetary policy andhousehold consumption. Thus, we investigate how the mortgage term affects householdconsumption during times the policy rate is changed. To answer the question an empirical method is utilized. The data used is quantitativesecondary data gathered from different sources and coordinated. The data material spans aperiod of roughly 17 years which contains three periods when the Swedish central bankchanged the policy rate and the observations are on a monthly basis, from january 2006 untilseptember 2023. To perform the analysis the statistical software IBM SPSS is used. Theregression analysis is implemented through the “General linear model”. The dependentvariable is household consumption. The explanatory variables include the proportion ofvariable-rate mortgages, disposable income, the policy rate as well as inflation. The policyrate and inflation are also lagged backward in time by one year respectively. The result of the regression analysis implicates that the effects of all the explanatory variablesin the study are statistically significant. As regards the policy rate though, only the laggedversion of the variable is statistically significant. The share of variable-rate mortgages, whichis a measurement of the mortgage term, has a negative effect on household consumption. Theeffect of disposable income is positive. Furthermore, both the policy rate and its laggedversion have negative effects on household consumption. In contrast, inflation has a positiveeffect while the lagged version of inflation has a negative effect on household consumptionwhich is larger in magnitude.
63

Desenvolvimento de polímeros de impressão molecular para microextração em ponteiras de bisfenol A em amostras de urina e análise por GC-MS / Development of molecularly imprinted polymer for disposable pipette extraction of bisphenol A in biological samples and analysis by GC-MS

Brigante, Tamires Amabile Valim 26 October 2015 (has links)
O Bisfenol A (BPA, acrônimo da língua inglesa - bisphenol A) é uma substância utilizada na fabricação de embalagens alimentícias e resinas odontológicas. Sua toxicidade deve-se ao fato de que, como disruptor endócrino, afeta o sistema reprodutor, cardiovascular, neuro-endócrino e pode apresentar potencial carcinogênico. Em métodos bioanalíticos, o preparo da amostra tem sido requerido para aumentar a seletividade e sensibilidade analítica, através da remoção dos interferentes da amostra biológica e concentração dos analitos, quase sempre presentes em níveis de traços. A microextração em ponteiras (DPX, acrônimo das iniciais em língua inglesa - Disposable Pipette Extraction), baseada no equilíbrio de sorção do soluto com a fase extratora, consiste em uma ponteira padrão de micropipeta modificada, na qual o sorvente está contido livremente entre dois filtros, permitindo rápida extração do analito em diferentes matrizes complexas. Os polímeros de impressão molecular (MIP acrônimo das iniciais em língua inglesa - Molecularly Imprinted Polymer) consistem em uma rede polimérica tridimensional que possui cavidades seletivas para o reconhecimento molecular do analito ou de substâncias de estrutura análoga. Essa rede polimérica é sintetizada ao redor da substância molde (analito), e a cavidade seletiva é formada após a remoção do molde. As vantagens do processo sol-gel para a síntese do MIP são o controle do tamanho e forma das partículas, ajuste da hidrofobicidade e alta estabilidade térmica. No presente trabalho, o MIP foi sintetizado e utilizado como sorvente para a técnica DPX para a determinação de bisfenol A em amostras de urina por cromatografia em fase gasosa acoplada à espectrometria de massas (GC-MS, acrônimo das iniciais em língua inglesa - Gas Chromatography coupled to Mass Spectrometry). O MIP foi sintetizado pela via sol-gel utilizando aminopropiltrietoxisilano (APTES) como mônomero funcional e tetraetil-orto-silicato (TEOS) como reagente de ligação cruzada. Como molde foram avaliados o BPA para o MIP, e o tetrabromobisfenol A (TBBPA) para o polímero molecularmente impresso com molécula análoga ao analito (DMIP, acrônimo das iniciais em língua inglesa - Dummy Molecularly Imprinted Polymer). Para avaliar a seletividade do MIP, o polímero não impresso (NIP, acrônimo das iniciais em língua inglesa - Non-imprinted Polymer) foi sintetizado seguindo o mesmo procedimento de síntese do MIP com exceção da adição da molécula molde. Apesar de a capacidade de sorção do MIP ser ligeiramente maior, o DMIP foi selecionado como sorvente para minimizar o efeito de memória. O DMIP foi caracterizado por microscopia eletrônica de varredura (MEV) e por espectroscopia vibracional na região do infravermelho por transformada de Fourier (FTIR, acrônico das inicias em língua inglesa - Fourier Transform Infrared). Os parâmetros da técnica DPX, tais como, o tempo de equilíbrio de sorção entre a amostra e o sorvente e condições de dessorção foram otimizadas por técnicas quimiométricas. A robustez do DMIP sintetizado via sol-gel foi comprovada pela reutilização deste sorvente por mais de 100 vezes, sem perda da eficiência da extração. O método desenvolvido DPX/GC-MS apresentou linearidade na faixa de 50 a 500 ng mL-1, precisão com CV (coeficientes de variação) entre 4 e 14% e de exatidão com valores de erro padrão relativo (EPR) de -13,6 a 12,3%. O método de referência utilizando a extração líquido-líquido e GC-MS (LLE/GC-MS), faixa de linearidade de 5 a 50 ng mL-1, foi desenvolvido e validado. Embora o método DPX/GC-MS inovador, quando comparado ao LLE/GC-MS, tenha apresentado maior limite de quantificação, apresentou as seguintes vantagens: simplicidade, rapidez e utilização de menores volumes de amostra e de solventes orgânicos na etapa do preparo da amostra / Bisphenol A (BPA) is widely used in food package and dental resins manufacturing. Its toxicity is due to its endocrine disruptor activity that affects the reproductive, cardiovascular, neurological system and may have carcinogenic potential. In bioanalytical methods the sample preparation has been required to increase the selectivity and analytical sensibility by removing the interfering from the biological matrix and concentration of the analytes that are in trace levels most of the times. The disposable pipette extraction (DPX) is based on sorption equilibrium of the analyte between the sample and the extraction phase. It consists in a pipette that contais the sorbent phase freely between two filters. Then, the extraction of the solute from the complex sample occurs quickly. Molecularly imprinted polymer is a tridimensional polimeric network that has selectivity cavities that can recognize an analyte or a substance with a similar structure. The polimeric network is synthesized around to a template molecule and after removing this template, a selective cavity is formed. The advantages of the sol-gel process for the synthesis of MIP are the control of the size and shape of the particles, hydrophobicity adjustment and high thermal stability. In the present study MIP was synthesized and used as sorbent to DPX method for determination of BPA in urine samples by gas chromatography coupled to mass spectrometry (GC-MS). Sol-gel methodoly was used to synthesize the polymers. Aminopropyltriethoxysilane (APTES) was used as a functional monomer and tetraethyl orthosilicate (TEOS) as crosslinking reagent. BPA and tetrabromobisphenol A (TBBPA) were evaluated as template to the synthesis of MIP and dummy molecularly imprinted polymer (DMIP) which is a molecularly imprinted polymer that uses a template structurally similar to the analyte. The non-imprinted polymer (NIP) was synthesized following the same procedure that MIP, except for the addition of template. It was made to verify the improvement of selectivity and sensibility of molecularly imprinted polymers. Although the sorption capacity of the MIP is slightly larger, DMIP has been selected as a sorbent in order to minimize the memory effect. The DMIP was characterized by Scanning Electron Microscopy (SEM) and Fourier Transform Infrared spectroscopy (FTIR). The parameters of DPX, such as time sorption equilibrium between the sample and the sorbent and desorption conditions were optimized by chemometrics. Robustness of DMIP sinthesized by sol-gel process was evidenciated for the reuse of DMIP for more than a 100 times. The developed method DPX/GC-MS showed linearity on the range from 50 to 500 ng ml-1, precision values with coefficient of variation (CV) betweeen 4 and 14% and accuracy with relative standard deviation values (RSD) from -13.6 to 12.3%. The reference method using liquid- liquid extraction and GC-MS (LLE/GC-MS) was developed and validated, showing linearity from 0.5 to 50 ng mL-1. Althout the innovative method DPX/GC-MS has showed limit of quantification larger than LLE/GC-MS, it presents the following advantages: simplicity, rapidy and utilization of smaller volumes of organic solvents on the sample preparation step
64

Vad händer med hållbarhet i en akut situation? : En kvalitativ intervjustudie på akutmottagningen och akutvårdsavdelningen vid Vrinnevisjukhuset I Norrköping / What happens to sustainability in an emergency situation? : A qualitative interview study at the emergency department and the emergency care department at Vrinnevi Hospital in Norrköping

Björkman, Mathias, Fridh, Emma January 2019 (has links)
Sverige är världsledande när det kommer till sjukvård och när det kommer till sopsortering men vad händer när dessa styrkor kombineras? Kan det skilja sig i uppfattningar bland vårdpersonal på ett svenskt sjukhus, samt hur ser uppfattningarna ut avdelningarna emellan. Denna studie syftar till att granska barriärer och möjliggörare för miljöarbetet på akutmottagningen och akutvårdsavdelningen på Vrinnevisjukhuset i Norrköping, med fokus på engångsartiklar. Uppsatsen bygger på kvalitativ intervjumetodik och intervjuerna har genomförts med fem intervjupersoner på akutmottagningen och akutvårdsavdelningen på Vrinnevisjukhuset i Norrköping. Resultatet av studien visar att anledningen till att engångsartiklar används på avdelningarna är till stor del på grund av hygieniska skäl samt svårigheter med återvinning på grund av smittorisk. Respondenterna tar även upp att sterila instrument och patientsäkerhet är viktigare än miljöarbete. Studien visar även att det finns skillnader mellan avdelningarna när det kommer till motivationen för miljöarbetet. Andra barriärer som upplevdes som problematiska på de båda avdelningarna var bristande kommunikation, okunskap och administration när det kommer till att kommunicera och implementera miljöåtgärder. Ekonomi spelar en central roll inom miljöarbetet när det kommer till Närsjukvården i östra Östergötland (NSÖ).  Det som respondenterna såg som möjliggörare var mer utbildning, bättre kommunikation, att skapa hållbara administrativa mål, tekniska lösningar, budget för miljöarbete och ett starkt stöd på lednings- och chefsnivå. / Sweden is one of the leading countries in the world when it comes to both health care and recycling, but what happens when these two are combined? Can it differ among health professionals in a typical Swedish hospital and can it differ in-between departments? This study aims to examine the barriers and enablers for environmental work in the emergency department and the emergency care unit at Vrinnevi hospital in Norrköping, with focus on disposable health care items. We have conducted qualitative interviews with five respondents at the emergency department and emergency care at Vrinnevi hospital. The interviews were designed with the aim to make respondents share their own perceptions and experiences about environmental work from a long career in healthcare. Our results suggest that the reason why disposable items are used in the departments is largely due to hygienic factors. It is also difficult to recycle in case of infection risk. The respondents stated that sterile instruments and patient safety are more important than environmental work. The study also shows that there are differences between the departments when it comes to the motivation for environmental work. Other barriers that were perceived as problematic in both departments were lack of attitude towards recycling, administration and communication. When it came to communication and implementation of environmental actions, the attitudes between the respondents differed. Financial resources also play a central role in the lack of environmental work within “Närsjukvården I östra Östergötland” (NSÖ) (the local health care in eastern Östergötland). The enablers that the respondents saw were more education, better communication, creating sustainable administrative goals, technical solutions, higher budget for environmental work and strong support at a management level.
65

Jämförande kostnadsanalys av retur- och engångsemaballage / Comparative cost analysis of reuse- and disposable packaging

Sundberg, Martin, Selin, Johan January 2013 (has links)
This report analyzes disposable packaging and returnable packaging with the methods life cycle analysis and life cycle costs analysis. These two different packaging are analyzed through the company Clas Ohlson’s packaging-flow. To get a picture of how the flow works, a visit at the company and email contact have been done with Clas Ohlson to get relevant information Today Clas Ohlson has a big flow of articles to the stores without larger variations in the demand, with the exception of autumn, which is when customers start shopping for Christmas. Clas Ohlson’s articles are placed on a pallet and are wrapped into plastic-film for protection and to make sure that nothing will be stolen. In this report Plastic-film is compared to the company Nycopac AB’s product Nyco Sleeve. In Sweden Posten takes care of Clas Ohlson’s transports and is the company’s third party-logistics provider. Nyco Sleeve is a type of pallet box, which is placed on a pallet with the possibility to place three units upon each other. The pallet box is possible to fold, which makes it doable to place pallet boxes upon each other in reverse transportation. Our Life cycle costs analysis shows that Nyco Sleeve is profitable compared to continue using plastic-film as secondary packaging. Nyco Sleeve demands a larger investment, almost seven times larger than the price for plastic-film but the expenses will be recovered relatively fast because of decreasing transportation costs. Posten’s pricing depends on each pallet place that is used which means that Nyco Sleeve’s higher weight does not affect the price. The total costs decreases because Nyco Sleeve increases the fill ratio on each pallet place, which results that less pallet places need to be used in the transport. If Nyco Sleeve is used the total pallet places decrease from about 116 000 to about 93 000 pallets considering 2012s flow. Due to decreasing costs each year, the pay-off-method shows that the investment reaches break even in about 0.7 years The life cycle analysis that examines the environmental impact of the packaging shows the same trend as the life cycle cost analysis, it is the transport that has the decisive influence on the environment. Important to note is that the transportations from Clas Ohlson’s warehouse to stores and the reverse transports stand for the largest carbon dioxide emissions and not the transportations from production or to waste disposal. The production phase’s emission is also important especially for Nyco Sleeve, which causes large amounts of emission compared to the plastic film. Decreasing transportations and that it is possible to reuse Nyco Sleeve even out the differences between the two packaging types when it comes to emission in production. The life cycle analysis’ scenario analysis shows that Nyco Sleeve environmental impact reaches break even after about two years compared to break even for the economic costs in 0.7 years. If only one loop is investigated the calculations show that Nyco Sleeve has larger environmental impact then plastic film but over time and when several loops are considered Nyco Sleeves carbon dioxide emission is economized. / Rapporten analyserar engångs- och returemballage genom de två analysmetoderna, livscykelkostnads- och livscykelanalys. Emballagen analyseras utifrån företaget Clas Ohlsons emballageflöde där studiebesök gjorts för att se hur flödet fungerar. Mailkontakt har också förekommit för annan viktig information kring företagets flöde av artiklar och emballage. Clas Ohlson har idag ett stort och jämnt flöde av produkter till deras butiker med säsongstoppar på hösten inför julhandeln. Deras produkter paketeras idag på lastpallar som sedan sveps in i plastfilm för att skydda och säkerställa att ingen stöld har skett. Det är detta engångsemballage, plastfilm, som jämförs emot returemballaget, Nyco Sleeve. Clas Ohlsons transporter sker idag med en tredjepartslogistiker där Posten är deras distributör inom Sveriges gränser, som är det system som undersöks. Nyco Sleeve är en form av pallbox som ställs på en lastpall och det går lasta tre stycken i höjd, ovan på varandra. Pallboxen går att fälla ihop vid returer och lastas även då ovan på varandra. Livscykelkostnadsanalysen visar att Nyco Sleeve är en ekonomisk lönsam investering i relation till att behålla plastfilmen som sekundärförpackning. Kostnaden att investera i Nyco Sleeve är ca sju gånger högre i jämförelse med inköpskostnaden för plastfilmen, men investeringen blir lönsam relativt snabbt eftersom Nyco Sleeve sänker transportkostnaderna. Posten tar idag betalt per pallplats och därmed gör inte tyngden på en Nyco Sleeve någon påverkan på den ekonomiska kostnaden. Kostnaden minskar genom användning av Nyco Sleeve eftersom fyllnadsgraden ökar och därmed minskar antalet levererade pallplatser. Skulle Nyco Sleeve användas minskas antalet från 116 100 stycken till ca 93 000 pallplatser utifrån Clas Ohlsons flöde under 2012. Genom den stora transportbesparingen per år visar pay-off-metoden att investeringen når break-even efter omkring 0,7 år. Livscykelanalysen som undersöker emballagens koldioxidutsläpp visar på samma tendens som livscykelkostnadsanalysen, att det är transporten som är den stora miljöboven. Viktigt att poängtera är att det är transporterna från Clas Ohlsons centrallager ut till butikerna och returtransporterna för samma sträcka som ger störst miljöpåverkan och inte transporterna från emballagens produktionsanläggningar till centrallagret eller till avfallshanteringen. Produktionen är även den en stor aktivitet som ger stor miljöpåverkan där Nyco Sleeve bidrar till betydligt större utsläpp än plastfilmen. Den stora skillnaden i miljöpåverkan från produktionen kompenseras genom de minskade transporterna och att Nyco Sleeve återanvänds. Livscykelanalysens scenarioanalys visar att Nyco Sleeves miljöpåverkan når break even efter ca två år. Undersöks bara en loop visar beräkningarna att Nyco Sleeve har större miljöpåverkan än om plastfilm används men detta inbesparas genom de minskade transporterna.
66

Desenvolvimento e caracterização de filmes poliméricos biodegradáveis para aplicação em sacolas descartáveis e sua análise de ecoeficiência

Carvalho, Jéssika Souza de January 2017 (has links)
Orientador: Prof. Dr. Derval dos Santos Rosa / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Ciência e Tecnologia Ambiental, 2017. / Nos dias de hoje, tem sido crescente a preocupação com os impactos ambientais provocados pelo descarte inadequado de sacolas plásticas após seu uso. Em busca de uma solução parcial para o descarte dessas, nos últimos anos vem aumentando o interesse em incrementar e desenvolver materiais biodegradáveis com características que permitam a sua utilização em embalagens e utensílios descartáveis e que contribuam com a sustentabilidade. Esse trabalho teve como objetivo desenvolver filmes poliméricos biodegradáveis, para uso em sacolas descartáveis de supermercado. Os filmes foram preparados utilizando PBAT, PLA e CaCO3, em diferentes composições. Os filmes das composições foram caracterizados por ensaios mecânicos e avaliação da biodegradação. Foram analisados também os desempenhos ambiental e econômico, ao longo do ciclo de vida dos filmes preparados, em comparação com sacolas usuais disponibilizadas nos supermercados (kraft e PEAD). Essa Análise de Ecoeficiência foi realizada segundo as normas ABNT NBR da série ISO 14040, com base em ferramentas de cálculo e bancos de dados de Avaliação de Ciclo de Vida internacionalmente reconhecidos. Os resultados do ensaio mecânico demonstraram que a incorporação de CaCO3 nos filmes diminuiu o alongamento na ruptura e a resistência máxima à tração e aumentou o módulo de Young dos materiais. Todas amostras apresentaram caráter hidrofílico, com ângulos de contato menores que 90º. As amostras com CaCO3 não apresentaram nítidas separação de fases, diferentemente da amostra sem carga, demonstrando que a incorporação do material favoreceu a dispersão e interação de PBAT/PLA. O CaCO3 reduziu e temperatura máxima de degradação das amostras. Com exceção da amostra de papel, todas apresentaram pequenos percentuais de massa sorvida. Após 360 dias do ensaio de biodegradação, os resultados mostraram que não houve uma perda de massa expressiva, no entanto, as amostras já apresentaram uma modificações superficiais, indicando ação de micro-organismos. Na Análise de Ecoeficiência foi possível observar que a incorporação de CaCO3 diminuiu significantemente os impactos econômicos das alternativas em estudo e favoreceu a ecoeficiência dos polímeros biodegradáveis. / Nowadays, there has been growing concern about the environmental impacts caused by the improper disposal of disposable plastic bags after use. In search of a partial solution for their disposal, the interest in improving and developing biodegradable materials of low cost with characteristics that allow its use in disposable containers and utensils that contribute to the sustainability have increased in recent years. This work aimed to develop polymeric biodegradable films for use in disposable supermarket bags. The films were prepared using PBAT, PLA and CaCO3, in different compositions. These films were characterized by mechanical tests and evaluation of biodegradation. There were also analyzed the environmental and economic performance over the life cycle of the films prepared in comparison with the usual alternatives available in supermarkets (paper and PEAD). This Eco-efficiency Analysis was performed according to NBR ISO 14040 standards series, based on calculation internationally recognized tools and databases of Life Cycle Assessment. The results of the mechanical tests demonstrated that the incorporation of CaCO3 in the films decreased the elongation at break and the maximum tensile strength at break of the materials, but increased the Young's modulus. All samples presented a hydrophilic character, with contact angles smaller than 90º. The samples with CaCO3 did not present a clear phase separation, unlike the sample with no load, demonstrating that the incorporation of the material favors the interaction of PBAT with PLA. The CaCO3 reduced the maximum degradation temperature of the samples. With the exception of the paper sample, all presented small percentage of sorbed mass. After 360 days of biodegradation test, the results showed that there was no significant mass loss, however, the samples already presented a superficial modifications, indicating action of microorganisms. In the Eco-efficiency Analysis it was possible to observe that the incorporation of CaCO3 significantly decreased the economic impacts of the alternatives under study and favored the eco-efficiency of the biodegradable polymers.
67

Biorreator wave como alternativa para expansão de células estromais mesenquimais

Silva, Juliana de Sá da 05 March 2015 (has links)
Made available in DSpace on 2016-06-02T19:56:57Z (GMT). No. of bitstreams: 1 6615.pdf: 4694610 bytes, checksum: 288df2441cd04d5e5e4c36da49c66cb9 (MD5) Previous issue date: 2015-03-05 / Financiadora de Estudos e Projetos / Mesenchymal stromal cells (MSCs) are required by the scientific community in the development and enhancement of therapeutic techniques in different fields of medicine. The MSCs are present in small concentrations in tissues, which makes necessary the expansion in vitro for enable studies and therapeutic applicability. These are cells with high sensitivity to environmental conditions of cultivation. So, for increase productivity in vitro is used the technology of bioreactors in the development of processes in order to produce high cell densities in less time, with reduce use of resources and maintaining a safe operation. The new concepts of "disposable bioreactors", as the wave-induced motion bioreactor or Wave bioreactor, with possibility operating in a closed system, controlled and automated, reduced investment cost and operation, less risk of contamination, higher level biosecurity, added to the fact of being a underexplored technology and already approved by the FDA (Food and Drugs Administration) becomes a highly attractive alternative bioprocessing for cultivation of animal cells in large scale. In this context, the present work aims to develop a protocol for cultivation of MSCs in the Wave Bioreactor System 2/10. Experiments were performed to characterize the CEMs's culture behavior in the Wave bioreactor to obtain high cell productivity while maintaining the therapeutic potential of the CEMs. The experiments were carried out with 2 L Cellbag and Cultispher-S microcarrier with 300 ml of α-MEM medium culture supplemented with glucose, glutamine, and arginine and 15% v/v fetal bovine serum at 37 ° C and pH between 6,9-7,4. In the preliminary experiments it was verified that most of the inoculated cells did not adhere to the microcarriers. It was shown that such behavior is due to low relation between adhesion area (AMC = total projected area of the microcarriers) and wet surface area of Cellbag (ASMCellbag), which in the normal condition of operation results an adhesion between 25,7 and 61,7% of the inoculated cells. To solve the problem were performed experiments reducing ACellbag which enabled improvements in cell adhesion by up to 100%. It was also found low performance of the cell expansion phase, presumably linked to operational problems like: microcarriers segregation in certain regions of the bioreactor causing depletion of nutrients, formation of aggregates of MCs colonized with cells and adhesion of MCs to Cellbag. In addition, it was observed that reducing CEM/MC ratio at the start of the culture, the cell expansion factor could be increased to values equal to or greater than 10. These results show that the Wave bioreactor has good potential for expansion of MSCs and that the same can be improved. / As células estromais mesenquimais (CEMs) estão sendo visadas pela comunidade científica no desenvolvimento e aprimoramento de técnicas terapêuticas em diferentes ramos da medicina. As CEMs estão presentes em pequenas concentrações nos tecidos, o que torna necessário a sua expansão in vitro para viabilizar pesquisas e a aplicabilidade terapêutica. Tratam-se de células com elevada sensibilidade em relação às condições do ambiente de cult ivo. Assim, para o aumento da produtividade in vitro utiliza-se a tecnologia de biorreatores no desenvolvimento de processos com objetivo de produzir altas densidades celulares em curto tempo, de forma econômica e respeitando as normas impostas pelos órgãos reguladores. O novo conceito de biorreator descartável, como o do biorreator com movimento induzido em forma de ondas, ou biorreator Wave, apresenta possibilidade de operação em sistema fechado segundo as boas práticas de fabricação (BPF), controlado e automatizado. O custo de investimento e operação reduzido, com menor risco de contaminação, maior nível de biossegurança, somado ao fato de utilizar uma tecnologia pouco explorada e já aprovada pelo FDA (Food and Drugs Administration) se transforma numa alternativa de bioprocessamento altamente atrativa para cultivo de células animais em larga escala. Nesse contexto, o presente trabalho tem por meta avaliar o desempenho do biorreator Wave 2/10 na expansão das CEMs. Para tal, foram realizados experimentos visando caracterizar o comportamento do cultivo nesse biorreator a fim de obter alta produtividade celular mantendo a potencialidade terapêutica das CEMs. Os experimentos foram realizados com saco plástico (doravante Cellbag) de 2 L e microcarregador (MC) Cultispher-S com 300 mL me io de cultivo α-MEM suplementado com glicose, glutamina e arginina e 15% v/v de soro fetal bovino a 37°C e pH entre 6,9-7,4. Nos experimentos preliminares constatou-se que grande parte das células inoculadas não aderiam aos microcarregadores. Comprovou-se que tal comportamento se devia à baixa relação entre área de adesão (AMC = área total projetada dos microcarregadores) e área de superfície molhada da Cellbag (ASMCellbag) que na condição normal de operação resultava numa adesão entre 25,7 e 61,7% das células inoculadas. Para melhorar a adesão foram realizados experimentos reduzindo a ASMCellbag, o que possibilitou melhoria na adesão celular em até 100%. Na etapa de expansão celular verificou-se baixo desempenho, presumivelmente vinculado a problemas de operação como: segregação de microcarregadores em determinadas regiões do biorreator provocando o esgotamento de nutrientes, formação de agregados de MCs colonizados com células e adesão dos MCs à Cellbag. Em adição, notou-se que diminuindo a relação CEM/MC no início do cultivo a expansão celular podia ser aumentada para valores iguais ou maiores que 10. Ao todo, os resultados mostraram que o biorreator Wave possui bom potencial para a expansão de CEMs e que o mesmo ainda pode ser melhorado.
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Specifika ošetřovatelské péče u pacienta s MRSA na operačním sále z pohledu anesteziologické sestry / Specifics of nurse care at the patient with MRSA on surgery from nurses' point of view.

KALÁBOVÁ, Miroslava January 2010 (has links)
Title of the thesis: Specifics of the nursing care of patients with MRSA in the operating room from an anesthesiology nurse perspective. The aim of this thesis was to identify the specifics of nursing care of a patient with the MRSA in the operating room from the perspective of nurses working in the operating room. In the theoretical part focus is given to nursing care and its specifics for a patient with MRSA. Chapters relating to the regime measures, barrier nursing procedures and the use of specific aids, instruments and tools are treated in detail. The nursing care provided by anesthesia nurses and perioperative nurses in the operating room is defined. To reach the goals the quantitative research through questionnaires was chosen. The research sample consisted of anesthesia nurses and perioperative care nurses. Two types of standardized questionnaires were used, consisted of closed questions where respondents chose an appropriate answer, and from semi-open questions where respondents could specify their answers, and in one case open questions. Both questionnaires were completed by 12 test questions, where respondents had the choice of three possible answers, where one answer was correct. The results of the investigation are summarized in two types of graphs. Bar charts were used in questions where more answers were possible to mark, and for a better clarity the results were supplemented by tables. Results to other questions, where options were limited by one answer, are shown in percentages in pie graphs. Our thesis is very narrowly focused, because we concentrated on specifics of nursing care in a patient with MRSA in the operating room. We have determined the specifics of barrier nursing, nursing problems in a patient with MRSA in the operating room. We have discovered barrier nursing procedures in a patient with MRSA in the operating room. We have also succeeded in assessing the knowledge of nurses working in the operating room. The goal was met. An interesting finding was that most of anesthetic nurses and perioperative nurses had responded that the structural and technical arrangement in the operating room was not satisfactory in terms of barrier nursing of a patient with MRSA. This problem was expected, owing to the author´s experience in operating theaters. Thus Hypothesis 1 is confirmed. In total five hypotheses were stated, four of which were confirmed and one was disproved. The aim of the thesis was to draw attention to problems in the operating room during nursing a patient with MRSA. In the course of the research work there were no problems, however, it is necessary to mention the lack of literature on MRSA with regard to nursing care in operating theaters. The theoretical section of this thesis could be recommended as a resource for the education plan created on the basis of information collected and the results of this research. The results of the research survey may serve for general public, anesthesia and perioperative nurses who could benefit from the educational plan in practice while providing nursing care for a patient with MRSA.
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Desenvolvimento de polímeros de impressão molecular para microextração em ponteiras de bisfenol A em amostras de urina e análise por GC-MS / Development of molecularly imprinted polymer for disposable pipette extraction of bisphenol A in biological samples and analysis by GC-MS

Tamires Amabile Valim Brigante 26 October 2015 (has links)
O Bisfenol A (BPA, acrônimo da língua inglesa - bisphenol A) é uma substância utilizada na fabricação de embalagens alimentícias e resinas odontológicas. Sua toxicidade deve-se ao fato de que, como disruptor endócrino, afeta o sistema reprodutor, cardiovascular, neuro-endócrino e pode apresentar potencial carcinogênico. Em métodos bioanalíticos, o preparo da amostra tem sido requerido para aumentar a seletividade e sensibilidade analítica, através da remoção dos interferentes da amostra biológica e concentração dos analitos, quase sempre presentes em níveis de traços. A microextração em ponteiras (DPX, acrônimo das iniciais em língua inglesa - Disposable Pipette Extraction), baseada no equilíbrio de sorção do soluto com a fase extratora, consiste em uma ponteira padrão de micropipeta modificada, na qual o sorvente está contido livremente entre dois filtros, permitindo rápida extração do analito em diferentes matrizes complexas. Os polímeros de impressão molecular (MIP acrônimo das iniciais em língua inglesa - Molecularly Imprinted Polymer) consistem em uma rede polimérica tridimensional que possui cavidades seletivas para o reconhecimento molecular do analito ou de substâncias de estrutura análoga. Essa rede polimérica é sintetizada ao redor da substância molde (analito), e a cavidade seletiva é formada após a remoção do molde. As vantagens do processo sol-gel para a síntese do MIP são o controle do tamanho e forma das partículas, ajuste da hidrofobicidade e alta estabilidade térmica. No presente trabalho, o MIP foi sintetizado e utilizado como sorvente para a técnica DPX para a determinação de bisfenol A em amostras de urina por cromatografia em fase gasosa acoplada à espectrometria de massas (GC-MS, acrônimo das iniciais em língua inglesa - Gas Chromatography coupled to Mass Spectrometry). O MIP foi sintetizado pela via sol-gel utilizando aminopropiltrietoxisilano (APTES) como mônomero funcional e tetraetil-orto-silicato (TEOS) como reagente de ligação cruzada. Como molde foram avaliados o BPA para o MIP, e o tetrabromobisfenol A (TBBPA) para o polímero molecularmente impresso com molécula análoga ao analito (DMIP, acrônimo das iniciais em língua inglesa - Dummy Molecularly Imprinted Polymer). Para avaliar a seletividade do MIP, o polímero não impresso (NIP, acrônimo das iniciais em língua inglesa - Non-imprinted Polymer) foi sintetizado seguindo o mesmo procedimento de síntese do MIP com exceção da adição da molécula molde. Apesar de a capacidade de sorção do MIP ser ligeiramente maior, o DMIP foi selecionado como sorvente para minimizar o efeito de memória. O DMIP foi caracterizado por microscopia eletrônica de varredura (MEV) e por espectroscopia vibracional na região do infravermelho por transformada de Fourier (FTIR, acrônico das inicias em língua inglesa - Fourier Transform Infrared). Os parâmetros da técnica DPX, tais como, o tempo de equilíbrio de sorção entre a amostra e o sorvente e condições de dessorção foram otimizadas por técnicas quimiométricas. A robustez do DMIP sintetizado via sol-gel foi comprovada pela reutilização deste sorvente por mais de 100 vezes, sem perda da eficiência da extração. O método desenvolvido DPX/GC-MS apresentou linearidade na faixa de 50 a 500 ng mL-1, precisão com CV (coeficientes de variação) entre 4 e 14% e de exatidão com valores de erro padrão relativo (EPR) de -13,6 a 12,3%. O método de referência utilizando a extração líquido-líquido e GC-MS (LLE/GC-MS), faixa de linearidade de 5 a 50 ng mL-1, foi desenvolvido e validado. Embora o método DPX/GC-MS inovador, quando comparado ao LLE/GC-MS, tenha apresentado maior limite de quantificação, apresentou as seguintes vantagens: simplicidade, rapidez e utilização de menores volumes de amostra e de solventes orgânicos na etapa do preparo da amostra / Bisphenol A (BPA) is widely used in food package and dental resins manufacturing. Its toxicity is due to its endocrine disruptor activity that affects the reproductive, cardiovascular, neurological system and may have carcinogenic potential. In bioanalytical methods the sample preparation has been required to increase the selectivity and analytical sensibility by removing the interfering from the biological matrix and concentration of the analytes that are in trace levels most of the times. The disposable pipette extraction (DPX) is based on sorption equilibrium of the analyte between the sample and the extraction phase. It consists in a pipette that contais the sorbent phase freely between two filters. Then, the extraction of the solute from the complex sample occurs quickly. Molecularly imprinted polymer is a tridimensional polimeric network that has selectivity cavities that can recognize an analyte or a substance with a similar structure. The polimeric network is synthesized around to a template molecule and after removing this template, a selective cavity is formed. The advantages of the sol-gel process for the synthesis of MIP are the control of the size and shape of the particles, hydrophobicity adjustment and high thermal stability. In the present study MIP was synthesized and used as sorbent to DPX method for determination of BPA in urine samples by gas chromatography coupled to mass spectrometry (GC-MS). Sol-gel methodoly was used to synthesize the polymers. Aminopropyltriethoxysilane (APTES) was used as a functional monomer and tetraethyl orthosilicate (TEOS) as crosslinking reagent. BPA and tetrabromobisphenol A (TBBPA) were evaluated as template to the synthesis of MIP and dummy molecularly imprinted polymer (DMIP) which is a molecularly imprinted polymer that uses a template structurally similar to the analyte. The non-imprinted polymer (NIP) was synthesized following the same procedure that MIP, except for the addition of template. It was made to verify the improvement of selectivity and sensibility of molecularly imprinted polymers. Although the sorption capacity of the MIP is slightly larger, DMIP has been selected as a sorbent in order to minimize the memory effect. The DMIP was characterized by Scanning Electron Microscopy (SEM) and Fourier Transform Infrared spectroscopy (FTIR). The parameters of DPX, such as time sorption equilibrium between the sample and the sorbent and desorption conditions were optimized by chemometrics. Robustness of DMIP sinthesized by sol-gel process was evidenciated for the reuse of DMIP for more than a 100 times. The developed method DPX/GC-MS showed linearity on the range from 50 to 500 ng ml-1, precision values with coefficient of variation (CV) betweeen 4 and 14% and accuracy with relative standard deviation values (RSD) from -13.6 to 12.3%. The reference method using liquid- liquid extraction and GC-MS (LLE/GC-MS) was developed and validated, showing linearity from 0.5 to 50 ng mL-1. Althout the innovative method DPX/GC-MS has showed limit of quantification larger than LLE/GC-MS, it presents the following advantages: simplicity, rapidy and utilization of smaller volumes of organic solvents on the sample preparation step
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Effects of minimum wages: do regional data tell a different story? / Effect of minimum wages: do regional data tell a different story?

Májková, Tereza January 2017 (has links)
This thesis examines the effects of an increase of minimum wage level on unemployment, employment, disposable income and risk of poverty. We contribute to the existing literature by directly comparing results resulting from two similar datasets, one working with national, one with regional data. We use different sets of explanatory variables to see whether they affect the results of the estimation. On national level, our results confirm positive effect of minimum wages on employment of adults and on disposable income - but these findings were not confirmed on regional level. With respect to the regional perspective, the results are however subject to substantial uncertainty and are prone to substantial sensitivity to empirical specification. We attribute this uncertainty mainly to the quality of the data - small number of observations together with large heterogeneity. JEL Classification E02, E24, J08, J30 Keywords minimum wages, employment effect, disposable income, risk of poverty, panel data, NUTS 2 regions, comparison Author's e-mail majkovat@gmail.com Supervisor's e-mail jaromir.baxa@fsv.cuni.cz

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