893 resultados para Lipid monolayers self-assembled on mercury


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C16-YEALRVANEVTLN, a peptide amphiphile (PA) incorporating a biologically active amino acid sequence found in lumican, has been examined for its influence upon collagen synthesis by human corneal fibroblasts in vitro, and the roles of supra-molecular assembly and activin receptor-like kinase ALK receptor signaling in this effect were assessed. Cell viability was monitored using the Alamar blue assay, and collagen synthesis was assessed using Sirius red. The role of ALK signaling was studied by receptor inhibition. Cultured human corneal fibroblasts synthesized significantly greater amounts of collagen in the presence of the PA over both 7-day and 21-day periods. The aggregation of the PA to form nanotapes resulted in a notable enhancement in this activity, with an approximately two-fold increase in collagen production per cell. This increase was reduced by the addition of an ALK inhibitor. The data presented reveal a stimulatory effect upon collagen synthesis by the primary cells of the corneal stroma, and demonstrate a direct influence of supra-molecular assembly of the PA upon the cellular response observed. The effects of PA upon fibroblasts were dependent upon ALK receptor function. These findings elucidate the role of self-assembled nanostructures in the biological activity of peptide amphiphiles, and support the potential use of a self-assembling lumican derived PA as a novel biomaterial, intended to promote collagen deposition for wound repair and tissue engineering purposes

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Högskolan Dalarna har i samarbete med Naturbränsle i Mellansverige AB genomfört studier på ett nytt fordon för transport av skogsflis. Fordonet är försett med egen lastningsutrustning (kran och skopa), vilket innebär att flisskördaren kan tippa flisen direkt på marken eller på en i förväg utlagd duk (minskar risken för föroreningar i samband med lastning). Studier har också genomförts på transport av flis med lastväxlarfordon och container (traditionell metod) för att jämförelser skall kunna göras mellan de olika fordonstyperna. Studierna har finansie¬rats via anslag från Statens Energimyndighet och via ”naturabidrag” från deltagande företag.Studierna visar att det nya transportfordonet är ett bättre alternativ än de traditionella last¬växlarfordonen på större objekt med långa transportavstånd. Dessutom pekar studien på att det är sannolikt är bättre även på små objekt under förutsättning att flisningskostnaden kan hållas på en rimlig nivå. Studierna visar också att det bör finnas en viss utvecklingspotential på det nya fordonet (teknik- och metodutveckling), varför det bedöms kunna konkurrera med lastväxlarfordonen även på andra typer av objekt.Jämfört med de traditionella lastväxlarfordonen har det nya fordonet bl.a. följande fördelar:•Transportarbetet blir lättare att planera i och med att beroendeförhållandet mellan in¬blandade maskiner och fordon för flisproduktion och transport upphör.••Risken för störningar i transportflödet minskar.•Miljövinsterna blir större jämfört med lastväxlarfordon som måste ställa ut tomma con¬tainrar innan flisningen kan påbörjas.•Det finns inget behov av lastmaskiner på terminalerna.•Flis kan mellanlagras i skogen.Till nackdelarna med det nya fordonet hör bl.a. följande:•Framkomligheten är något sämre än för lastväxlarfordon på mycket smala och kurviga skogsbilvägar.•Det finns en viss risk för att föroreningar följer med vid lastning av fordonet. Studies were carried out on a new vehicle for transport of fuel chips from the forest. The vehicle was equipped with a crane and a bucket meaning that the chipper may tip the fuel chips right on the ground or on a mat (vira from wood processing industry) to prevent from dirt such as sand and stones when loading. Studies were also carried out on traditional main hauling with transport bins. Transport speed was the same for all vehicles except for the new self-loader on forest roads with lower quality.The studies show that the new system probably is a better alternative on large sites with long transport distances and on sites with only little parking place for transport bins. It is also likely that the new vehicle may be used on very small sites if they are close to each other and if moving cost for the chipper is low.The studies show that the new vehicle has the following advantages:•Transport and other work may be planned in a better way leading to that stress de¬creases.•Dependence between chipper operators and truck drivers decreases.•The risk for disturbances in transport flow decreases.•Environment benefits compared to traditional system with higher traffic intensity (less exhaust gases and lower stress on roads and bridges).•No need for loading machines on terminals.•Easier to store fuel chips on landing.

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This master thesis presents a new technological combination of two environmentally friendly sources of energy in order to provide DHW, and space heating. Solar energy is used for space heating, and DHW production using PV modules which supply direct current directly to electrical heating elements inside a water storage tank. On the other hand a GSHP system as another source of renewable energy provides heat in the water storage tank of the system in order to provide DHW and space heating. These two sources of renewable energy have been combined in this case-study in order to obtain a more efficient system, which will reduce the amount of electricity consumed by the GSHP system.The key aim of this study is to make simulations, and calculations of the amount ofelectrical energy that can be expected to be produced by a certain amount of PV modules that are already assembled on a house in Vantaa, southern Finland. This energy is then intended to be used as a complement to produce hot water in the heating system of the house beside the original GSHP system. Thus the amount of electrical energy purchased from the grid should be reduced and the compressor in the GSHP would need fewer starts which would reduce the heating cost of the GSHP system for space heating and providing hot water.The produced energy by the PV arrays in three different circuits will be charged directly to three electrical heating elements in the water storage tank of the existing system to satisfy the demand of the heating elements. The excess energy can be used to heat the water in the water storage tank to some extent which leads to a reduction of electricity consumption by the different components of the GSHP system.To increase the efficiency of the existing hybrid system, optimization of different PV configurations have been accomplished, and the results are compared. Optimization of the arrays in southern and western walls shows a DC power increase of 298 kWh/year compared with the existing PV configurations. Comparing the results from the optimization of the arrays on the western roof if the intention is to feed AC power to the components of the GSHP system shows a yearly AC power production of 1,646 kWh.This is with the consideration of no overproduction by the PV modules during the summer months. This means the optimized PV systems will be able to cover a larger part of summer demand compared with the existing system.

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Buscar desempenho superior do capital humano é fator chave para as organizações exercerem maior competitividade e atingir níveis superiores ao da concorrência. Para este intento, conquistar o maior comprometimento dos trabalhadores é fundamental para aumentar o desempenho individual e, se destaca como a principal via para construção de vantagem competitiva duradoura nas organizações onde, ao líder, é delegado o papel de motivador. Estudos recentes desvendam uma nova abordagem para compreender o impacto da liderança sobre os subordinados. A autenticidade. O líder autêntico tem por mérito gerar auto-eficiência em seus liderados, é através do respeito com que trata seus subordinados, demonstra elevada consistência em seus atos, avalia os pontos de vista de seus comandados, provê retorno sobre desempenho e possue valores que o levam a ser justo, tendo ainda, a capacidade de extrair de seus liderados esforço adicional. Portanto, quanto mais “autêntica como pessoa”, mais poderá impactar diretamente na eficácia de seus seguidores. Mas, este estudo revelou que há um componente de mediação entre o líder autêntico e o maior comprometimento organizacional. O contrato psicológico. Em sua dimensão relacional, principalmente, que trata de lealdade e estabilidade, o contrato psicológico se destacou por mediar a relação entre a autenticidade do líder e o maior comprometimento da equipe, ou seja, a autenticidade do líder molda a forma como o indivíduo se vincula à organização, sendo assim uma descoberta relevante a qual nos auxilia a compreender quais são os verdadeiros fatores que influenciam no maior comprometimento e, conseqüente, aumento no desempenho dos trabalhadores.

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Considerando os avanços da pesquisa e teoria da psicologia do risco e, em particular, da perspectiva do risco como sentimentos, ressaltando a interação entre cognição e emoção na análise de ameaças, esta tese propõe e testa um modelo conceitual sobre o efeito da vulnerabilidade (risco como sentimento) em intenções comportamentais de serviços relacionados a automóveis. Este estudo teve como hipótese que a autoeficácia percebida pelo consumidor diminui ou elimina o efeito da vulnerabilidade nas intenções comportamentais de perpetuidade de relacionamento com a empresa de serviço. Estimularam o interesse de pesquisa tanto a carência de pesquisas sobre o papel da vulnerabilidade no consumo de serviços não relacionados à área da saúde ou ao corpo do consumidor, quanto a carência de pesquisas sobre a relação entre a vulnerabilidade e as intenções comportamentais. Testou-se em um único modelo, o impacto previsto pelos processos cognitivos e afetivos que envolvem a análise de ameaça (sentimentos de vulnerabilidade, risco e severidade das falhas) e de capacidade de enfrentamento (autoeficácia) na intenção comportamental, no contexto específico de consumo de serviços relativos a automóveis. O modelo de mensuração proposto foi avaliado quanto à dimensionalidade, validade e confiabilidade pelo uso de análise fatorial confirmatória; posteriormente, avaliou-se a relação causal proposta nas hipóteses pelo modelo completo de equações estruturais. O modelo de mensuração proposto foi avaliado quanto à dimensionalidade, validade e confiabilidade pelo uso de análise fatorial confirmatória; posteriormente, avaliou-se a relação proposta nas hipóteses pelo modelo completo de equações estruturais, usando-se o software Amos e a estimativa por máxima verossimilhança. O modelo foi estimado em uma amostra de 202 respondentes. Os dados foram coletados por meio de um levantamento eletrônico transversal e os achados da pesquisa apontam para a confirmação das hipóteses de que (1) o risco percebido cognitivamente, sentimentos de vulnerabilidade e a autoeficácia influenciam as intenções comportamentais. Não foi possível suportar a hipótese de que (2) a severidade das possíveis falhas de serviço tem relação com risco ou com sentimentos de vulnerabilidade. Esses achados ajudam a compreender a relação entre intenções comportamentais e sentimentos de vulnerabilidade. Implicações para o desenvolvimento teórico da pesquisa na área e implicações gerenciais são discutidas. Os resultados auxiliam a compreensão dos resultados de estudos realizados nos EUA nas últimas décadas. Os achados oferecem uma contribuição teórica ao entendimento do fenômeno da vulnerabilidade, a adaptação de uma escala de medida para o fenômeno no contexto brasileiro e aplicado a serviços que não sejam de saúde e cuidados com o corpo. Do ponto de vista gerencial, o estudo alerta para o fato de a vulnerabilidade exercer influência no desempenho comercial de empresas de serviços automotivos, visto que ela influência negativamente a recomendação positiva e a manutenção de relacionamentos de negócios. Os achados sugerem que os gestores de empresas de serviços devem empreender esforços para reduzir a vulnerabilidade do consumidor por meio de informações que o auxiliem na negociação e avaliação do serviço ao minimizar incertezas.

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This research aims to acknowledge the virtual dating phenomenon. The research deals with this phenomenon in Orkut, a social networking website. Thus, it considers debates and forums that were present in a Brazilian Orkut online community called Conheci meu amor pela internet (I met my love through the Internet). As a staring point the research dealt with issues such as: what are the debates about? How can we deal with practices that question their own dating process? According to the initial hypothesis, these debates reveal different contemporary social aspects: 1) they emerge as a response to demands on behalf of a society that is rather reflexive. This reflexive element is fundamental for the constitution of the self 2) these debates work as support elements in social relations that are built upon this sphere. In this context, individuals write about themselves and constitute themselves as real individuals that acquire a sense as subjects; and 3) people discuss online dating as form reconstructing former experiences. Empirical analysis demonstrates that these forums and polls present themselves as a social phenomenon that allows a particular form of self presentation on the internet. In order for these subjects to present themselves they built their own self narratives. What is possible to acknowledge considering these narratives is that there is a predominance of the element of intrigue that is further solved and demonstrate a satisfactory result. These narrators then choose online dating situation that present happy endings and happiness that are associated to romantic ideals that are worthwhile being shown. The contents present in these narratives are dealt with by the research. Thus, this work defends the thesis that the online dating narratives are a mixture of facts and fiction once all experiences deal with romantic imaginary as well as personal dating experience. Thus, the research is an attempt to understand what goes on the forums and debates that deal with the fictionalized and dramatized daily experiences in the performances that are similar to games. This is possible due to the fact that there is use of romantic fables and concrete experiences realized by online dating

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The present work concerns an auto-ethnographic study based on life experiences and reflections of an educator at Escola Viva Preschool and Elementary-Middle School, located in the city center of Natal, Rio Grande do Norte. As a cognitive model of operation, we use the metaphor of the Circle Dance. The objective of this study is to identify, interpret and describe the ludopoetics that are achieved through a Musical Education program, which we denominate, Humanescent. The data of this investigation was derived from the music making by Preschool and Elementary-Middle School students at Escola Viva during 2007, 2008 and 2009, from which 20 learners were selected to form the corpus, along with the description and interpretation of photos of their experiences and sand tray scenes. We justify the methodological systemization of the research based on our own pedagogical practice, which supports Musical Education in the schools based on the principals of Embodiment, Autopoesis and Flow. The methodological systemization was developed through an Action Research model and on the concepts of Systemic Development, with the goal of re-reading the context investigated through the structuring of categories of Ludopoesis: Self-esteem, Self-territory, Self-connectivity, Self-realization and Selfworth. We used an observant-participant research approach with regard to the perception of emergent knowledge, the surroundings, the experience lived and the contextual and vibration of the circumstances. Besides this, we used projection to interpret the experiences lived, in the form of drawings, short poems, letters or sand tray scenes as symbolic interpretations of experience. In the unfolding of the Ludopoetic Process (Selfesteem, Self-territory, Self-connectivity, Self-realization and Selfworth) we draw conclusions about the relevance of the ludic musical experience, which foments the formation of the self based on music learning, and which is demonstrated in the Embodiment of the learners. In the auto-formative process (of learners and educators) we observe the importance of pedagogical work based on Musical Humanescent Education that gives value to the music making path to the construction of music and performance in play, creativity, and sensibility. The experience of making music in a playful way allows for organization of the self and its autonomous production in the joy of living within a ludopoetic process. These findings highlight the educator as in a permanent state of selfformation, which generates moments of flow. However, in Musical Humanescent Education, music is learned collectively, doing a circle dance, experiencing love, fostering an expansion of the creative spirit, and giving recognition to playfulness as a necessary condition for education and to the value of music made with the true nature and sensibilities of the educators

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This work presents a spray-dryer designed to oxalate-niobate precursors and suitable for the production of Niobium Carbide. The dryer was intended to produce powders of controlled particle size. First, the precursor is dissolved in water to produce a solution of known concentration and then it is atomized on the spray-dryer to produce the powder. This equipment consists of a 304 stainless steel chamber, 0.48 m x 1.9 m (diameter x length), with a conical shape at the lower portion, which is assembled on a vertical platform. The chamber is heated by three 4 kW electrical resistances. In this process, drying air is heated as it flows inside a serpentine surrounding the chamber, in contrary to more traditional processes in which the hot drying air is used to heat the component. The air enters the chamber at the same temperature of the chamber, thus avoiding adherence of particles on the internal surface. The low speed flow is concurrent, directed from the top to the bottom portion of the chamber. Powders are deposited on a 0.4 m diameter tray, which separates the cylindrical portion from the conical portion of the chamber. The humid air is discharged though a plug placed underneath the collecting tray. A factorial experimental planning was prepared to study the influence of five parameters (concentration, input flow, operation temperature, drying air flow and spray air flow) on the characteristics of the powders produced. Particle size distribution and shape were measured by laser granulometry and scanning electronic microscopy. Then, the powders are submitted to reaction in a CH4 / H2 atmosphere to compare the characteristics of spray-dried powders with powders synthetizided by conventional methods

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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In this work calibration models were constructed to determine the content of total lipids and moisture in powdered milk samples. For this, used the near-infrared spectroscopy by diffuse reflectance, combined with multivariate calibration. Initially, the spectral data were submitted to correction of multiplicative light scattering (MSC) and Savitzsky-Golay smoothing. Then, the samples were divided into subgroups by application of hierarchical clustering analysis of the classes (HCA) and Ward Linkage criterion. Thus, it became possible to build regression models by partial least squares (PLS) that allowed the calibration and prediction of the content total lipid and moisture, based on the values obtained by the reference methods of Soxhlet and 105 ° C, respectively . Therefore, conclude that the NIR had a good performance for the quantification of samples of powdered milk, mainly by minimizing the analysis time, not destruction of the samples and not waste. Prediction models for determination of total lipids correlated (R) of 0.9955, RMSEP of 0.8952, therefore the average error between the Soxhlet and NIR was ± 0.70%, while the model prediction to content moisture correlated (R) of 0.9184, RMSEP, 0.3778 and error of ± 0.76%

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Aim: To assess orthodontic intrusion effects on periodontal tissues in dogs' pre-molars with class III furcations treated with open flap debridement (OFD) or with guided tissue regeneration (GTR) associated to bone autograft (BA).Material and Methods: Class III furcations were created in the pre-molars of seven mongrel dogs. After 75 days, teeth were randomly treated with OFD or GTR/BA. After 1 month, metallic crowns were assembled on pre-molars and connected apically to mini-implants by nickel-titanium springs. Teeth were randomly assigned to orthodontic intrusion (OFD+I and GTR/BA+I) groups or no movement (OFD and GTR/BA) groups. Dogs were sacrificed after 3 months of movement and 1 month retention.Results: All class III furcations were closed or reduced to class II or I in the intrusion groups, while 50% of the lesions in non-moved teeth remained unchanged. Intruded teeth presented higher probing depth and lower gingival marginal level than non-moved teeth (p < 0.01). Clinical attachment gain was reduced in the intrusion groups by the end of retention (p < 0.05). OFD+I presented smaller soft tissue area and larger bone tissue area than other groups (p < 0.05).Conclusion: Orthodontic intrusion with anchorage via mini-implants improved the healing of class III furcation defects after OFD in dogs. GTR/BA impaired those results.

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The behaviour of dc longitudinal and transverse conductivity in self-assembled plastdoped films of polyaniline has been studied over the range of 9 K to 320 K, under different applied mechanical pressures. We observe a progressive evolution of the conductivity picture as the applied pressure is increased, especially in the transverse direction, where the conductivity tends to lower as the pressure is increased. (C) 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

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Micro-cube-shaped lead zirconate titanate was synthesized using the microwave-assisted hydrothermal method. Photoluminescence and field emission scanning electron microscopy were used for monitoring the formation of mesocrystals. Based on these results, a growth mechanism was then proposed which involved nanoparticle aggregation, nanoplate self-assembly on specific architecture and the final formation of mesoscopic micro-cube-shaped lead zirconate titanate. (C) 2011 Elsevier B. V. All rights reserved.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Two cis-related palladium(II) complexes [PdCl(2)(PPh(3))(tu)] (1) and [PdCl(2)(tmen)] (2) {PPh(3) = triphenylphosphine, tu = thiourea, tmen = N,N,N,N-tetramethylethylenediamine} have been synthesized and characterized by elemental analysis, IR and NMR spectroscopies, and single crystal X-ray diffraction. In 1, N-H center dot center dot center dot Cl hydrogen bonds are responsible for the formation of a dimer which connects to an adjacent one through weak C-H center dot center dot center dot Cl interactions, yielding 1D tapes. The crystal packing of compound 2 consists of zigzag ribbons of [PdCl(2)(tmen)] self-assembled by C-H center dot center dot center dot Cl hydrogen bonds which also holds the chains together, giving rise to a 2D layered structure. (C) 2006 Elsevier B.V. All rights reserved.