Influence of implant positioning in extraction sockets on osseointegration: Histomorphometric analyses in dogs

Aim: To evaluate the influence of implant positioning into extraction sockets on osseointegration. Material and methods: Implants were installed immediately into extraction sockets in the mandibles of six Labrador dogs. In the control sites, the implants were positioned in the center of the alveolus, while in the test sites, the implants were positioned 0.8 mm deeper and more lingually. After 4 months of healing, the resorptive patterns of the alveolar crest were evaluated histomorphometrically. Results: All implants were integrated in mineralized bone, mainly composed of mature lamellar bone. The alveolar crest underwent resorption at the control as well as at the test sites. After 4 months of healing, at the buccal aspects of the control and test sites, the location of the implant rough/smooth limit to the alveolar crest was 2±0.9 mm and 0.6±0.9 mm, respectively (P<0.05). At the lingual aspect, the bony crest was located 0.4 mm apically and 0.2 mm coronally to the implant rough/smooth limit at the control and test sites, respectively (NS). Conclusions: From a clinical point of view, implants installed into extraction sockets should be positioned approximately 1 mm deeper than the level of the buccal alveolar crest and in a lingual position in relation to the center of the alveolus in order to reduce or eliminate the exposure above the alveolar crest of the endosseous (rough) portion of the implant. © 2009 John Wiley & Sons A/S.

The contribution of biofuels to the sustainability of development in Latin America and the Caribbean

Includes bibliography

Quality management and competitiveness: the diffusion of the ISO 9000 standards in Latin America and recommendations for government strategies

Includes bibliography

Quantitative assessment of a free trade agreement between MERCOSUR and the European Union

Incluye Bibliografía

Fractional order and dynamic simulation of a system involving an elastic wide plate

Numerous researchers have studied about nonlinear dynamics in several areas of science and engineering. However, in most cases, these concepts have been explored mainly from the standpoint of analytical and computational methods involving integer order calculus (IOC). In this paper we have examined the dynamic behavior of an elastic wide plate induced by two electromagnets of a point of view of the fractional order calculus (FOC). The primary focus of this study is on to help gain a better understanding of nonlinear dynamic in fractional order systems. © 2011 American Institute of Physics.

Relevance of lovebirds (Agapornis roseicollis Selby, 1836) in experimental epidemiology of Newcastle disease

Studies were made to clarify the role that was played by the lovebirds (Agapornis roseicollis) in the epidemiological plan, under the perspective of its being a potential source of infection of Newcastle Disease Virus (NDV). The study used Specific-Pathogen-Free chicks (SPF) that were housed with lovebirds inoculated with a pathogenic strain (velogenic viscerotropic) of NDV pathogenic to chickens, by the ocular-nasal via. Each group was composed of six SPF chicks and four lovebirds. After five days of the inoculation of the lovebirds with NDV, SPF chicks were put together with each group of lovebirds. Cloacae swabs were collected after 9, 14 and 21 days post-challenge in both species (lovebirds and SPF chicks) for genome viral excretion by Reverse Transcription Polymerase Chain Reaction (RT-PCR). Lovebirds did not demonstrate any clinical signs of NDV. They were refractory to the clinical disease with the NDV. However, NDV genome was detected 9 and 21 days after challenge. This study shows that lovebirds can be carriers NDV. Moreover, 100% of SPF chicks allocated with the infected lovebirds demonstrated clinical signs and lesions suggestive of NDV. In these birds, NDV genome was detected 9, 14 and 21 days after challenge. Thus, the transmission of the pathogenic virus from the lovebirds to SPF chicks that were housed together was evident until 21 days of the experimental infection. This study reveals the importance of lovebirds from the epidemiological point of view as potential source of infection of the NDV to other avian species that could be raised near this species. © Asian Network for Scientific Information, 2012.

Efficiency analysis of an isolated high voltage gain converter operating in resonant and non-resonant mode

This paper presents an efficiency investigation of an isolated high step-up ratio dc-dc converter aimed to be used for energy processing from low-voltage high-current energy sources, like batteries, photovoltaic modules or fuel-cells. The considered converter consists of an interleaved active clamp flyback topology combined with a voltage multiplier at the transformer secondary side capable of two different operating modes, i.e. resonant and non-resonant according to the design of the output capacitors. The main goal of this paper is to compare these two operating modes from the component losses point of view with the aim of maximize the overall converter efficiency. The approach is based on losses prediction using steady-state theoretical models (designed in Mathcad environment), taking into account both conduction and switching losses. The models are compared with steady-state simulations and experimental results considering different operating modes to validate the approach. © 2012 IEEE.

The challenge of industrial competitiveness

Includes bibliography

Some lessons of the Argentine privatization process

Includes bibliography

The renewed currency of Raúl Prebisch

Includes bibliography

Experimental results and thermodynamic analysis of a natural gas small scale cogeneration plant for power and refrigeration purposes

In this work, experimental results are reported for a small scale cogeneration plant for power and refrigeration purposes. The plant includes a natural gas microturbine and an ammonia/water absorption chiller fired by steam. The system was tested under different turbine loads, steam pressures and chiller outlet temperatures. An evaluation based on the 1st and 2nd Laws of Thermodynamics was also performed. For the ambient temperature around 24°C and microturbine at full load, the plant is able to provide 19 kW of saturated steam at 5.3 bar (161 °C), corresponding to 9.2 kW of refrigeration at -5 °C (COP = 0.44). From a 2nd law point-of-view, it was found that there is an optimal chiller outlet temperature that maximizes the chiller exergetic efficiency. As expected, the microturbine presented the highest irreversibilities, followed by the absorption chiller and the HRSG. In order to reduce the plant exergy destruction, it is recommended a new design for the HRSG and a new insulation for the exhaust pipe. © 2013 Elsevier Ltd. All rights reserved.

Sustainable production of biologically active molecules of marine based origin

The marine environment offers both economic and scientific potential which are relatively untapped from a biotechnological point of view. These environments whilst harsh are ironically fragile and dependent on a harmonious life form balance. Exploitation of natural resources by exhaustive wild harvesting has obvious negative environmental consequences. From a European industry perspective marine organisms are a largely underutilised resource. This is not due to lack of interest but due to a lack of choice the industry faces for cost competitive, sustainable and environmentally conscientious product alternatives. Knowledge of the biotechnological potential of marine organisms together with the development of sustainable systems for their cultivation, processing and utilisation are essential. In 2010, the European Commission recognised this need and funded a collaborative RTD/SME project under the Framework 7-Knowledge Based Bio-Economy (KBBE) Theme 2 Programme 'Sustainable culture of marine microorganisms, algae and/or invertebrates for high value added products'. The scope of that project entitled 'Sustainable Production of Biologically Active Molecules of Marine Based Origin' (BAMMBO) is outlined. Although the Union is a global leader in many technologies, it faces increasing competition from traditional rivals and emerging economies alike and must therefore improve its innovation performance. For this reason innovation is placed at the heart of a European Horizon 2020 Strategy wherein the challenge is to connect economic performance to eco performance. This article provides a synopsis of the research activities of the BAMMBO project as they fit within the wider scope of sustainable environmentally conscientious marine resource exploitation for high-value biomolecules. © 2013 Elsevier B.V.

Algoritmos busca tabu paralelos aplicados ao planejamento da expansão da transmissão de energia elétrica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Produção e caracterização da protease coagulante obtida por fermentação submersa a partir do fungo termofílico Thermomucor indicae-seudaticae N31

Pós-graduação em Engenharia e Ciência de Alimentos - IBILCE