221,687 research outputs found
Bio-fuels, wait a minute
No full textThe ethical relevance of this topic is clear. Bio-fuels show great promise as a sustainable energy source, but there are also worries that its production will be at the expense of food security, especially for people in developing countries. The author defends the unconventional position that the first generation bio-fuels is not sustainable and that the Netherlands should focus exclusively on second generation bio-fuels, which are made from non-food crops. One could argue about this and the jury suspects that there are enough people to be found at TU Delft who would disagree. However, the jury applauds the fact that the author takes a clear moral standpoint and - even more important - tries to give a plausible argumentation to support it. Furthermore, the author shows himself to be technically well informed
Some investigations concerning the CTMC and the ODE model derived from Bio-PEPA
No full text<p>Bio-PEPA is a recently defined language for the modelling and analysis of biochemical networks. It supports an abstract style of modelling, in which discrete levels of concentration within a species are considered instead of individual molecules. A finer granularity for the system corresponds to a smaller concentration step size and therefore to a greater number of concentration levels. This style of model is amenable to a variety of different analysis techniques, including numerical analysis based on a CMTC with states reflecting the levels of concentration.</p>
<p>In this paper we present a formal definition of the CTMC with levels derived from a Bio-PEPA system. Furthermore we investigate the relationship between this CTMC and the system of ordinary differential equations (ODEs) derived from the same model. Using Kurtz's theorem, we show that the set of ODEs derived from the Bio-PEPA model is able to capture the limiting behaviour of the CTMC obtained from the same system. Finally, we define an empirical methodology to find the granularity of the Bio-PEPA system for which the ODE and the CTMC with levels are in a good agreement. The proposed definition is based on a notion of distance between the two models. We demonstrate our approach on a model of the Repressilator, a simple biochemical network with oscillating behaviour.</p>
Design and Development of Software Tools for Bio-PEPA
No full textThis paper surveys the design of software tools for the Bio-PEPA process algebra. Bio-PEPA is a high-level language for modelling biological systems such as metabolic pathways and other biochemical reaction networks. Through providing tools for this modelling language we hope to allow easier use of a range of simulators and model-checkers thereby freeing the modeller from the responsibility of developing a custom simulator for the problem of interest. Further, by providing mappings to a range of different analysis tools the Bio-PEPA language allows modellers to compare analysis results which have been computed using independent numerical analysers, which enhances the reliability and robustness of the results computed
Determinants of Chilean youth voter registration: Evidence for the Bio Bio region
No full textYouth voter registration is a worldwide phenomenon that exhibits a marked decline over the last two decades. On this basis, this article presents evidence regarding those factors that determine the voter registration of Chilean youth, in particular, the inhabitants of Bio Bio region. The methodology uses a linear model, proposed by Silberman and Durden (1975), which considers a relationship between voter registration and several social/economic variables. The model is estimated using a dynamic panel for the Bio Bio region, which includes its 54 communes and 10 planning territories for the years 2003 and 2009. The results indicate that, at commune level, the main determinants of youth voter registration are citizen participation and poverty rates, while ethnic aspects are also affecting female voter registration, and only citizen participation rate has some influence over male voter registration. Finally, at territory level, the results show that citizen participation rate is a cross determinant of youth voter registration in the Bio Bio region.citizen participation; panel data; unobserved effects model; voter registration
GeneFisher-P: variations of GeneFisher as processes in Bio-jETI
No full textLamprecht A-L, Margaria T, Steffen B, Sczyrba A, Hartmeier S, Giegerich R. GeneFisher-P: variations of GeneFisher as processes in Bio-jETI. BMC Bioinformatics. 2008;9(Suppl 4): S13.Background: PCR primer design is an everyday, but not trivial task requiring state-of-the-art software. We describe the popular tool GeneFisher and explain its recent restructuring using workflow techniques. We apply a service-oriented approach to model and implement GeneFisher-P, a process-based version of the GeneFisher web application, as a part of the Bio-jETI platform for service modeling and execution. We show how to introduce a flexible process layer to meet the growing demand for improved user-friendliness and flexibility. Results: Within Bio-jETI, we model the process using the jABC framework, a mature model-driven, service-oriented process definition platform. We encapsulate remote legacy tools and integrate web services using jETI, an extension of the jABC for seamless integration of remote resources as basic services, ready to be used in the process. Some of the basic services used by GeneFisher are in fact already provided as individual web services at BiBiServ and can be directly accessed. Others are legacy programs, and are made available to Bio-jETI via the jETI technology. The full power of service-based process orientation is required when more bioinformatics tools, available as web services or via jETI, lead to easy extensions or variations of the basic process. This concerns for instance variations of data retrieval or alignment tools as provided by the European Bioinformatics Institute (EBI). Conclusions: The resulting service- and process-oriented GeneFisher-P demonstrates how basic services from heterogeneous sources can be easily orchestrated in the Bio-jETI platform and lead to a flexible family of specialized processes tailored to specific tasks
Alkaline phosphatase immobilization onto Bio-Gide(R) and Bio-Oss(R) for periodontal and bone regeneration.
No full textItem does not contain fulltextAIM: To evaluate the effect of alkaline phosphatase (ALP) immobilization onto Bio-Gide((R)) in vitro, and to study the in vivo performance of ALP-enriched Bio-Gide((R)) and/or Bio-Oss((R)) with the purpose to enhance periodontal regeneration. MATERIALS AND METHODS: Alkaline phosphatase ALP was immobilized onto Bio-Gide((R)) and Bio-Oss((R)) . Forty-eight rats received periodontal defects, which were treated according to one of the following strategies: Bio-Gide((R)), Bio-Gide((R)) -ALP, Bio-Gide((R)) -ALP/Bio-Oss((R)), Bio-Gide((R)) /Bio-Oss((R)) -ALP, Bio-Gide((R)) -ALP/Bio-Oss((R)) -ALP, or empty. Micro-CT and histological analysis were performed. RESULTS: A 30 min ALP-deposition time was determined as optimal from mineralization capacity assessment and consequently used as Bio-Gide((R)) -ALP membranes in the animal experiment. In vivo results showed that after 2 weeks, the defect and implanted materials were still visible, an inflammatory response was present, and membrane degradation was ongoing. Bone formation, although limited, was observed in the majority of Bio-Gide((R)) -ALP specimens and all of the Bio-Gide((R)) /Bio-Oss((R)) -ALP specimens, and was significantly higher compared with Bio-Gide((R)) and empty controls. After 6 weeks, the defects and particles were still visible, whereas membranes were completely degraded. The inflammatory response was decreased and bone formation appeared superior for Bio-Gide((R)) -ALP treated defects. CONCLUSION: Immobilization of ALP onto guided tissue regeneration (GTR)/ guided bone regeneration (GBR)-materials (Bio-Gide((R)) and Bio-Oss((R))) can enhance the performance of these materials in GTR/GBR procedures.01 juni 201
The Bio-Economy Concept and Knowledge Base in a Public Goods and Farmer Perspective
No full textCurrently an industrial perspective dominates the EU policy framework for a European bio-economy. The Commission’s proposal on the bio-economy emphasises greater resource-efficiency, largely within an industrial perspective on global economic competitiveness, benefiting capital-intensive industries at higher levels of the value chain. However a responsible bio-economy must initially address the sustainable use of resources. Many farmers are not only commodity producers but also providers of quality food and managers of the eco-system. A public goods-oriented bio-economy emphasises agro-ecological methods, organic and low (external) input farming systems, ecosystem services, social innovation in multi-stakeholder collective practices
and joint production of knowledge. The potential of farmers and SMEs to contribute to innovation must be fully recognised. This approach recognises the importance of
local knowledge enhancing local capabilities, while also accommodating diversity and complexity. Therefore the bio-economy concept should have a much broader scope
than the dominant one in European Commission innovation policy. Socio-economic research is needed to inform strategies, pathways and stakeholder cooperation towards
sustainability goals
Investigation of engine performance and exhaust gas emissions by using bio-diesel in compression ignition engine and optimisation of bio-diesel production from feedstock by using response surface methodology
No full textBio-diesel, derived from the transesterification of vegetable oils or animal fats with simple alcohols, has attracted more and more attention recently. As a cleaner burning diesel alternative, bio-diesel claims to have many attractive features including: biodegradability,
nontoxicity, renewability and low emission profiles. Free fatty acid (FFA) esterification and
triglyceride (TG) transesterification with low alcohols molar ratio are the central reactions for
the bio-diesel production. This study presents an experimental investigation into the effects of
running biodiesel fuel and its blends on conventional diesel engines. Bio-fuels provide a way to produce fuels without redesigning any of the engine technology present today, yet allowing
for green house emissions to decrease.
Bio-diesel is one of these types of emerging bio-fuels, which has an immediate alternative fuel, while providing a decrease in green house gas emissions, as well as a solution to recycling used Waste Vegetable Oils which are otherwise disposed. This study shows how by blending bio-diesel with petroleum diesel at intervals of B5, B10, B15, and B20 decrease green house gas emissions significantly while maintaining similar performance output and efficiency with respect to 100% petroleum diesel.
The focus of this research is to optimize the biodiesel production from crude sunflower
oil. The effect of variables including methanol/oil molar ratio, NaOH catalyst concentration, reaction time, reaction temperature, and rate of mixing on the bio-diesel yield was examined and optimized by response surface methodology (RSM). Besides, a second-order model was deduced to predict the biodiesel yield. Confirmation experiment was further conducted, validating the efficacy of the model.
Transesterification of sunflower oil was carried out using low molecular weight alcohols and sodium hydroxide. For sunflower oil, a central composite design with eight factorial, six center and six axial points was used to study the effect of catalyst concentration, molar ratio of methanol to sunflower oil and reaction temperature on percentage yield of the biodiesel. Catalyst concentration and molar ratio of methanol to sunflower oil were the most influential variables affecting percentage conversion and percentage initial absorbance.
Maximum percentage yield of 95 % is predicted at a catalyst concentration of 1.1 % (wt/wt) and methanol to sunflower oil molar ratio of 6.8:1 at reaction time of 66 min and temperature of 35°C. In general, the sunflower oil biodiesel exhibited friendly environmental benefits and acceptable stability, demonstrating its feasibility as an alternative fuel
Bio-remediation of a sludge containing hydrocarbons
No full textBio-augmentation has been used as a bio-remediation option for hydrocarbon-contaminated, oily-sludge restoration. This sludge was obtained from the Bonny-Terminal Improvement Project (BTIP) for Bonny Island, near Port Harcourt, Nigeria. Its total hydrocarbon-content (THC) was 69,372 mg/kg of sludge. Three treatment reactors (X, Y and Z) and one control reactor (A) were charged with 1500 g of oily sludge and 250 g of agricultural soil (i.e. an oily sludge to soil ratio of 6:1), the mixture homogenized and allowed to settle for seven days before various CFUs were added to reactors X, Y and Z. Reactor A did not receive any bio-preparation. The agricultural soil served both as a nutrient and a microbe carrier. With regularly scheduled mixing and watering, the THC reduction in the oily sludge varied between 40.7% and 53.2% within two weeks as well as between 63.7% and 84.5% within six weeks of applying the bio-remediation. The CFU counts of the added bio-preparation varied between 1.2 × 1212 and 3.0 × 1012 CFU/g of sludge and decreased to 7.0 × 1011 CFU/g of sludge by the end of the sixth week. The pH of the degrading sludge fluctuated between 6.5 and 7.8 during the same period. When compared with the performance of the indigenous microbes in the control sample, the added bio-preparation evidently increased the THC reduction rate in the oily sludge
Tecniche per rendere il bio più competitivo in pianura
No full textTecniche per rendere il bio più competitivo in pianur
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