912 resultados para Design Build Project Delivery System
Resumo:
The aim of this study was to evaluate the effects of the photodynamic therapy (PDT) on the inflammatory infiltrate and on the collagen network organization in human advanced chronic periodontitis Two different drug delivery systems (DDS) were tested (liposomes and nanoemulsions) to determine if the effects of PDT could differ according to the DDS used Sixteen patients presenting two teeth with chronic advanced periodontitis and Important tooth mobility with clinical indication of extraction were included in the group liposomes (group L n = 8) or in the group nanoemulsions (group N n = 8) in order to compare the effects of each DDS Seven days before extractions one tooth of each patient was treated with PDT using phthalocyanine derivatives as photosensitizers and the contralateral tooth was taken as control In group L the density of gingival collagen fibers (66 +/- 19%) was significantly Increased (p < 0 02) when compared to controls (35 +/- 21%) Concerning the antigen-presenting cells PDT had differential effects depending on the drug delivery system the number of macrophages was significantly decreased (p < 0 05) in group L while the number of Langerhans cells was significantly decreased in group N (p < 0 02) These findings demonstrate that PDT presents an impact on gingival Inflammatory phenomenon during chronic periodontitis and leads to a specific decrease of antigen-presenting cells populations according to the drug delivery system used (C) 2010 Elsevier B V All rights reserved
Resumo:
This study reports on the development and characterization of bovine serum albumin (BSA) nanospheres containing Silicon(IV) phthalocyanine (NzPc) and/or maghemite nanoparticles (MNP), the latter introduced via ionic magnetic fluid (MF). The nanosized BSA-loaded samples were designed for synergic application while combining Photodynamic Therapy and Hyperthermia. Incorporation of MNP in the albumin-based template, allowing full control of the magnetic content, was accomplished by adding a highly-stable ionic magnetic fluid sample to the albumin suspension, following heat denaturing. The material`s evaluation was performed using Zeta potential measurements and scanning electron microscopy. The samples were characterized by steady-state techniques and time-resolved fluorescence. The in vitro assay, using human fibroblasts, revealed no cytotoxic effect in all samples investigated, demonstrating the potential of the tested system as a synergistic drug delivery system.
Resumo:
The cellular uptake and antimycobacterial activity of usnic acid (UA) and usnic acid-loaded liposomes (UA-LIPOs) were assessed on J774 macrophages. The minimal inhibitory concentration (MIC) and the minimal bactericidal concentration (MBC) of UA and UA-LIPO against Mycobacterium tuberculosis were determined. Concentrations required to inhibit 50% of cell proliferation (IC(50)) were 22.5 (+/- 0.60) and 12.5 (+/- 0.26) mu g/ml, for UA and UA-LIPO, respectively. The MICs of UA and UA-LIPO were 6.5 and 5.8 mu g/mL, respectively. The MBC of UA-LIPO was twice as low (16 mu g/mL) as that of UA (32 mu g/mL). An improvement in the intracellular uptake of UA-LIPO was found (21.6 x 10(4) +/- 28.3 x 10(2) c.p.s), in comparison with UA (9.5 x 10(4) +/- 11.4 x 10(2) c.p.s). In addition, UA-LIPO remains much longer inside macrophages (30 hours). All data obtained from the encapsulation of usnic acid into liposomes as a drug delivery system (DDS) indicate a strong interaction between UA-liposomes and J774 macrophages, thereby facilitating UA penetration into cells. Considering such a process as ruling the Mycobacterium-transfection by magrophages, we could state that associating UA with this DDS leads to an improvement in its antimycobacterial activity.
Resumo:
In this study, the photodynamic action of liposomes (LP) and nanocapsules (NC) containing Chloroaluminum phthalocyanine (CIAIPc), on the human melanoma cell (WM 1552C), was assessed. The light source was setup at 672 nm, which corresponds to the maximum absorption wavelength of the CIAIPc. Both colloidal carriers presented size in nanometric scale as well as negative zeta potential. The cellular damage was light dose dependent ranging from 30% of cell death at 70 mJ.cm(-2) to 90% of death at 700 mJ.cm(-2). However, the photocytotoxic effect of LP at 70 mJ.cm(-2) was slightly more efficient to induce cellular death than NC formulation. At 140 mJ.cm(-2), and 700 mJ.cm(-2) both nanocarriers were equally efficient to induce cellular damage. Therefore, in the present work, the maximum phototoxic effect was obtained with 700 mJ.cm(-2) of light dose, in combination with 0.29 mu g.mL(-1) of CIAIPc encapsulated into LP and NC. The cells were also positive to annexin V, after the PDT treatment with LP and NC, showing that one of the mechanisms of cellular death involved is apoptosis. In summary, the potential of LP and NC as a drug delivery system, in Photodynamic Therapy (PDT) against melanoma, has been confirmed using a lower concentration of the photosensitizer and lower light doses than that applied in current protocols. This is an innovative proposal to treat melanoma cell lines that until now have not received the benefit of the PDT protocol for treatment.
Resumo:
Background Distraction osteogenesis (DO) is a method of producing new bone directly from the osteotomy site by gradual traction of the divided bone fragments. Aim The purpose of the present study was to evaluate histomorphometrically whether acute DO would constitute a viable alternative to the conventional continuous distraction treatment and also to verify the capacity of a recombinant human BMP (rhBMP-2) associated with monoolein gel to stimulate bone formation in the acute distraction process. Materials and methods Forty-eight Wistar rats were assigned to three groups: Group 1, treated at a conventional continuous distraction rate (0.5 mm/day), Group 2, treated with acute distraction of 2.5 mm at the time of the surgical procedure, and Group 3, subjected to acute distraction associated with rhBMP-2. The animals from each experimental group were killed at the end of the second or fourth post-operative weeks and the volume fraction of newly formed bone trabeculae was estimated in histological images by a differential point-counting method. Results The results showed that after 2 and 4 weeks, bone volumes in the rhBMP-2 group were significantly higher than in the other groups (P < 0.05), but no significant difference was observed in the volume fraction of newly formed bone between the continuous and acute DO groups. Conclusion In conclusion, the study indicates that rhBMP-2 can enhance the bone formation at acute DO, which may potentially reduce the treatment period and complications related to the distraction procedure. To cite this article:Issa JPM, do Nascimento C, Lamano T, Iyomasa MM, Sebald W, de Albuquerque Jr RF. Effect of recombinant human bone morphogenetic protein-2 on bone formation in the acute distraction osteogenesis of rat mandibles.Clin. Oral Impl. Res. 20, 2009; 1286-1292.doi: 10.1111/j.1600-0501.2009.01799.x.
Resumo:
Este trabalho final de mestrado baseou-se no acompanhamento da construção do hotel SANA Amoreiras, situado na Avenida Duarte Pacheco nº 12. O empreiteiro geral foi a empresa FDO Construções. Existindo também uma equipa de fiscalização, LMSA, contratada pelo Dono de Obra de forma a efectuar todo o controlo de qualidade. O TFM baseou-se no estágio efectuado para o Dono de obra do hotel onde fui devidamente acompanhada por uma engenheira, orientadora de estágio, que acompanhou de perto o desempenho da minha actividade. Esta função teve como objectivos a gestão de projecto de hotel, interligação entre projectistas e empreiteiro geral, bem prestar o devido acompanhamento de todos trabalhos a realizar. Acompanhei a realização de dois quartos modelo onde o objectivo do Dono de Obra foi testar as diversas soluções ao nível de revestimentos, sanitários, iluminação, mobiliário, decoração e outras soluções de arquitectura, soluções estas a implementar no hotel. Acompanhei também a realização de reuniões de compatibilização e coordenação de todos os projectos de especialidades com o projecto de arquitectura, nomeadamente Avac, Instalações eléctricas, Comunicações, Segurança, Águas, Esgotos, Gás, Incêndio, Cozinhas de forma a ser possível efectuar consultas aos empreiteiros e adjudicar todas estas empreitadas. Foi efectuada uma abordagem à descrição do hotel, suas características, indicação das razões que levaram à sua construção e descrição das várias empreitadas de construção realizadas até então, tal como, demolição, escavação, estrutura, acabamentos e especialidades.
Resumo:
Nos dias que correm questões ambientais e considerações energéticas obrigam a uma inovação constante na procura de soluções de baixo consumo energético e de impacto ambiental baixo, nomeadamente no que diz respeito aos sistemas de climatização e refrigeração. Têm vindo a ser criadas medidas, tanto a nível internacional como nacional, no sentido de reduzir as emissões nocivas para a atmosfera, consequência do excessivo consumo de combustíveis fósseis, e do aumento da rentabilidade da energia e maior utilização de energias renováveis. O presente estudo de dimensionamento de um sistema de absorção, a brometo de lítio/água, com coletores solares, tem por base o sistema de compressão existente num edifício de serviços no centro de Lisboa. Foi efetuada uma analise simplificada dos seus dados de consumo energético, de maneira a verificar a viabilidade económica da substituição do equipamento existente e instalação de um sistema de coletores solares. Concluiu-se que a substituição do equipamento e a instalação de coletores solar, não é atrativa do ponto de vista económico, nesta solução em particular. Contudo, verifica-se uma considerável redução do impacto ambiental do consumo energético do edifício.
Resumo:
In this work it is proposed the design of a mobile system to assist car drivers in a smart city environment oriented to the upcoming reality of Electric Vehicles (EV). Taking into account the new reality of smart cites, EV introduction, Smart Grids (SG), Electrical Markets (EM), with deregulation of electricity production and use, drivers will need more information for decision and mobility purposes. A mobile application to recommend useful related information will help drivers to deal with this new reality, giving guidance towards traffic, batteries charging process, and city mobility infrastructures (e. g. public transportation information, parking places availability and car & bike sharing systems). Since this is an upcoming reality with possible process changes, development must be based on agile process approaches (Web services).
Resumo:
Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia Mecânica
Resumo:
Trabalho Final de Mestrado para a obtenção do grau de Mestre em Engenharia Civil na Área de Especialização de Estruturas
Resumo:
This paper presents a fractional calculus perspective in the study of signals captured during the movement of a mechanical manipulator carrying a liquid container. In order to study the signals an experimental setup is implemented. The system acquires data from the sensors, in real time, and, in a second phase, processes them through an analysis package. The analysis package runs off-line and handles the recorded data. The results show that the Fourier spectrum of several signals presents a fractional behavior. The experimental study provides useful information that can assist in the design of a control system and the trajectory planning to be used in reducing or eliminating the effect of vibrations.
Resumo:
The interest in the development of climbing robots has grown rapidly in the last years. Climbing robots are useful devices that can be adopted in a variety of applications, such as maintenance and inspection in the process and construction industries. These systems are mainly adopted in places where direct access by a human operator is very expensive, because of the need for scaffolding, or very dangerous, due to the presence of an hostile environment. The main motivations are to increase the operation efficiency, by eliminating the costly assembly of scaffolding, or to protect human health and safety in hazardous tasks. Several climbing robots have already been developed, and other are under development, for applications ranging from cleaning to inspection of difficult to reach constructions. A wall climbing robot should not only be light, but also have large payload, so that it may reduce excessive adhesion forces and carry instrumentations during navigation. These machines should be capable of travelling over different types of surfaces, with different inclinations, such as floors, walls, or ceilings, and to walk between such surfaces (Elliot et al. (2006); Sattar et al. (2002)). Furthermore, they should be able of adapting and reconfiguring for various environment conditions and to be self-contained. Up to now, considerable research was devoted to these machines and various types of experimental models were already proposed (according to Chen et al. (2006), over 200 prototypes aimed at such applications had been developed in the world by the year 2006). However, we have to notice that the application of climbing robots is still limited. Apart from a couple successful industrialized products, most are only prototypes and few of them can be found in common use due to unsatisfactory performance in on-site tests (regarding aspects such as their speed, cost and reliability). Chen et al. (2006) present the main design problems affecting the system performance of climbing robots and also suggest solutions to these problems. The major two issues in the design of wall climbing robots are their locomotion and adhesion methods. With respect to the locomotion type, four types are often considered: the crawler, the wheeled, the legged and the propulsion robots. Although the crawler type is able to move relatively faster, it is not adequate to be applied in rough environments. On the other hand, the legged type easily copes with obstacles found in the environment, whereas generally its speed is lower and requires complex control systems. Regarding the adhesion to the surface, the robots should be able to produce a secure gripping force using a light-weight mechanism. The adhesion method is generally classified into four groups: suction force, magnetic, gripping to the surface and thrust force type. Nevertheless, recently new methods for assuring the adhesion, based in biological findings, were proposed. The vacuum type principle is light and easy to control though it presents the problem of supplying compressed air. An alternative, with costs in terms of weight, is the adoption of a vacuum pump. The magnetic type principle implies heavy actuators and is used only for ferromagnetic surfaces. The thrust force type robots make use of the forces developed by thrusters to adhere to the surfaces, but are used in very restricted and specific applications. Bearing these facts in mind, this chapter presents a survey of different applications and technologies adopted for the implementation of climbing robots locomotion and adhesion to surfaces, focusing on the new technologies that are recently being developed to fulfill these objectives. The chapter is organized as follows. Section two presents several applications of climbing robots. Sections three and four present the main locomotion principles, and the main "conventional" technologies for adhering to surfaces, respectively. Section five describes recent biological inspired technologies for robot adhesion to surfaces. Section six introduces several new architectures for climbing robots. Finally, section seven outlines the main conclusions.
Resumo:
This paper analyzes the signals captured during impacts and vibrations of a mechanical manipulator. In order to acquire and study the signals an experimental setup is implemented. The signals are treated through signal processing tools such as the fast Fourier transform and the short time Fourier transform. The results show that the Fourier spectrum of several signals presents a non integer behavior. The experimental study provides valuable results that can assist in the design of a control system to deal with the unwanted effects of vibrations.
Resumo:
O objetivo deste trabalho consistiu em projetar, construir e testar um protótipo em laboratório de uma fonte de alimentação de alta tensão que permita descargas elétricas {estáveis e de dimensões reduzidas}, de modo a que possa ser utilizada, dada a sua essencialidade, na fabricação de redes de período longo (LPG) em fibra ótica nos chamados turning points. Estes são pontos de elevada sensibilidade, fundamentais no desenvolvimento tecnológico de sensores em fibra ótica, em particular, de sensores refractométricos. O protótipo da fonte de alimentação é composto por um regulador do tipo BUCK, um inversor para alimentação do transformador de alta tensão, o circuito de realimentação e controlo PWM e um microcontrolador para o comando da fonte. Posteriormente procedeu-se à otimização dos parâmetros de descarga, o que conduziu a fabricação de redes de período longo com períodos inferiores a 150 micrómetros. Este é um resultado sem paralelo a nível internacional no que concerne ao uso da técnica do arco elétrico.
Resumo:
RESUMO - Este estudo teve como objectivo contribuir para o conhecimento sobre a equidade no sector do medicamento, com uma análise empírica aplicada ao sistema de saúde português. Para o efeito avaliou-se se indivíduos com as mesmas necessidades em saúde, mas com diferentes níveis de rendimento, tiveram idêntica prestação no que diz respeito ao medicamento. Adicionalmente, aprofundou-se esta análise através da identificação de factores associados ao sistema de prestação ou ao utente que contribuíram para gerar iniquidades, com particular destaque para os comportamentos de não aquisição de medicamentos – não adesão primária. A avaliação da equidade foi efectuada através de duas abordagens distintas, mas complementares: uma sob a perspectiva da utilização e outra sob a perspectiva da distribuição da despesa pública com medicamentos. Para estas análises aplicaram-se métodos baseados nos índices de concentração, utilizando dados do Inquérito Nacional de Saúde 2005/06 e dados relativos aos encargos do Serviço Nacional de Saúde com medicamentos. Os resultados revelaram que, perante as mesmas necessidades, o sistema de prestação tende a favorecer os indivíduos de nível socioeconómico superior, quer na utilização quer na distribuição de recursos do Estado com medicamentos. Adicionalmente, a aplicação do método da decomposição do índice de concentração revelou que tanto o rendimento como o nível educacional são atributos individuais que estão associados à iniquidade na utilização de medicamentos. A iniquidade observada neste estudo pode resultar de barreiras em diferentes fases do processo terapêutico, entre as quais se destacam o não acesso à prescrição médica ou a não aquisição dos medicamentos prescritos. Foi este comportamento - designado de não adesão primária - que se analisou na segunda parte da tese. Para tal cruzaram-se os dados de prescrição electrónica com os dados de dispensa no Serviço Nacional de Saúde. Os resultados revelaram que a taxa de não adesão primária foi cerca de 20% e que este comportamento está associado ao sexo feminino ou ser jovem, assim como a características do sistema de prestação como o valor dos copagamentos. Estes dados indiciam que as barreiras na aquisição podem ser indutoras de iniquidades na utilização de medicamentos. A identificação de iniquidade na utilização de medicamentos e dos factores que contribuem para esta situação constituem o primeiro passo para uma estratégia de redução da iniquidade que, de acordo com os resultados desta tese, deve abranger não só o sistema de saúde mas também outras áreas das políticas públicas em Portugal.