980 resultados para clustering, free-form, ottimizzazione, remeshing


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Post-processing a finite element solution is a well-known technique, which consists in a recalculation of the originally obtained quantities such that the rate of convergence increases without the need for expensive remeshing techniques. Postprocessing is especially effective in problems where better accuracy is required for derivatives of nodal variables in regions where Dirichlet essential boundary condition is imposed strongly. Consequently such an approach can be exceptionally good in modelling of resin infiltration under quasi steady-state assumption by remeshing techniques and with explicit time integration, because only the free-front normal velocities are necessary to advance the resin front to the next position. The new contribution is the post-processing analysis and implementation of the freeboundary velocities of mesolevel infiltration analysis. Such implementation ensures better accuracy on even coarser meshes, which in consequence reduces the computational time also by the possibility of employing larger time steps.

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Usually, data warehousing populating processes are data-oriented workflows composed by dozens of granular tasks that are responsible for the integration of data coming from different data sources. Specific subset of these tasks can be grouped on a collection together with their relationships in order to form higher- level constructs. Increasing task granularity allows for the generalization of processes, simplifying their views and providing methods to carry out expertise to new applications. Well-proven practices can be used to describe general solutions that use basic skeletons configured and instantiated according to a set of specific integration requirements. Patterns can be applied to ETL processes aiming to simplify not only a possible conceptual representation but also to reduce the gap that often exists between two design perspectives. In this paper, we demonstrate the feasibility and effectiveness of an ETL pattern-based approach using task clustering, analyzing a real world ETL scenario through the definitions of two commonly used clusters of tasks: a data lookup cluster and a data conciliation and integration cluster.

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Dissertação de mestrado em Ciências da Comunicação (área de especialização em Publicidade e Relações Públicas)

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We consider a population of agents distributed on the unit interval. Agents form jurisdictions in order to provide a public facility and share its costs equally. This creates an incentive to form large entities. Individuals also incur a transportation cost depending on their location and that of the facility which makes small jurisdictions advantageous. We consider a fairly general class of distributions of agents and generalize previous versions of this model by allowing for non-linear transportation costs. We show that, in general, jurisdictions are not necessarily homogeneous. However, they are if facilities are always intraterritory and transportation costs are superadditive. Superadditivity can be weakened to strictly increasing and strictly concave when agents are uniformly distributed. Keywords: Consecutiveness, stratification, local public goods, coalition formation, country formation. JEL Classification: C71 (Cooperative Games), D71 (Social Choice; Clubs; Committees; Associations), H73 (Interjurisdictional Differentials and Their Effects).

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Specific properties emerge from the structure of large networks, such as that of worldwide air traffic, including a highly hierarchical node structure and multi-level small world sub-groups that strongly influence future dynamics. We have developed clustering methods to understand the form of these structures, to identify structural properties, and to evaluate the effects of these properties. Graph clustering methods are often constructed from different components: a metric, a clustering index, and a modularity measure to assess the quality of a clustering method. To understand the impact of each of these components on the clustering method, we explore and compare different combinations. These different combinations are used to compare multilevel clustering methods to delineate the effects of geographical distance, hubs, network densities, and bridges on worldwide air passenger traffic. The ultimate goal of this methodological research is to demonstrate evidence of combined effects in the development of an air traffic network. In fact, the network can be divided into different levels of âeurooecohesionâeuro, which can be qualified and measured by comparative studies (Newman, 2002; Guimera et al., 2005; Sales-Pardo et al., 2007).

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One of the methods used for controlling cattle rabies in Brazil consists of vaccination. Sometimes, however, rabies occurs in cattle supposedly protected. Since rabies vaccine batches are officially controlled by tests performed on laboratory animals, it is questionable whether the minimal mandatory requirements really correspond to immunogenicity in the target species. We have analyzed the association among potencies of rabies vaccines tested by the NIH test, the contents and form (free-soluble or virus-attached) of rabies glycoprotein (G) in the vaccine batches, and the virus-neutralizing antibodies (VNA) titers elicited in cattle. No correlation was found between G contents in the vaccine batches and the NIH values, whatever the presentation of G. There was no correlation either between NIH values and VNA titers elicited in cattle. There was, however, a positive correlation (r = 0.8681; p = 0.0001) between the amounts of virion-attached G present in the vaccine batches and VNA elicited in cattle. This was not observed when the same analysis was performed with total-glycoprotein or free-soluble glycoprotein. The study demonstrated that NIH values can not predict the effect of the immunogen in cattle. On the other hand, the quantification of virus-attached rabies glycoprotein has a strong correlation with VNA elicited in cattle.

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Thank you Chairman I would like to extend a warm welcome to our keynote speakers, David Byrne of the European Commission, Derek Yach from the World Health Organisation, and Paul Quinn representing Congressman Marty Meehan who sends his apologies. When we include the speakers who will address later sessions, this is, undoubtedly, one of the strongest teams that have been assembled on tobacco control in Europe. The very strength of the team underlines what I see as a shift – a very necessary shift – in the way we perceive the tobacco issue. For the last twenty years, we have lived out a paradox. It isn´t a social side issue. I make no apology for the bluntness of what I´m saying, and will come back, a little later, to the radicalism I believe we need to bring – nationally – to this issue. For starters, though, I want to lay it on the line that what we´re talking about is an epidemic as deadly as any suffered by human kind throughout the centuries. Slower than some of those epidemics in its lethal action, perhaps. But an epidemic, nonetheless. According to the World Health Organisation tobacco accounted for just over 3 million annual deaths in 1990, rising to 4.023 million annual deaths in 1998. The numbers of deaths due to tobacco will rise to 8.4 million in 2020 and reach roughly 10 million annually by 2030. This is quite simply ghastly. Tobacco kills. It kills in many different ways. It kills increasing numbers of women. It does its damage directly and indirectly. For children, much of the damage comes from smoking by adults where children live, study, play and work. The very least we should be able to offer every child is breathable air. Air that doesn´t do them damage. We´re now seeing a global public health response to the tobacco epidemic. The Tobacco Free Initiative launched by the World Health Organisation was matched by significant tobacco control initiatives throughout the world. During this conference we will hear about the experiences our speakers had in driving these initiatives. This Tobacco Free Initiative poses unique challenges to our legal frameworks at both national and international levels; in particular it raises challenges about the legal context in which tobacco products are traded and asks questions about the impact of commercial speech especially on children, and the extent of the limitations that should be imposed on it. Politicians, supported by economists and lawyers as well as the medical profession, must continue to explore and develop this context to find innovative ways to wrap public health considerations around the trade in tobacco products – very tightly. We also have the right to demand a totally new paradigm from the tobacco industry. Bluntly, the tobacco industry plays the PR game at its cynical worst. The industry sells its products without regard to the harm these products cause. At the same time, to gain social acceptance, it gives donations, endowments and patronage to high profile events and people. Not good enough. This model of behaviour is no longer acceptable in a modern society. We need one where the industry integrates social responsibility and accountability into its day-to-day activities. We have waited for this change in behaviour from the tobacco industry for many decades. Unfortunately the documents disclosed during litigation in the USA and from other sources make very depressing reading; it is clear from them that any trust society placed in the tobacco industry in the past to address the health problems associated with its products was misplaced. This industry appears to lack the necessary leadership to guide it towards just and responsible action. Instead, it chooses evasion, deception and at times illegal activity to protect its profits at any price and to avoid its responsibilities to society and its customers. It has engaged in elaborate ´spin´ to generate political tolerance, scientific uncertainty and public acceptance of its products. Legislators must act now. I see no reason why the global community should continue to wait. Effective legal controls must be laid on this errant industry. We should also keep these controls under review at regular intervals and if they are failing to achieve the desired outcomes we should be prepared to amend them. In Ireland, as Minister for Health and Children, I launched a comprehensive tobacco control policy entitled “Towards a Tobacco Free Society“. OTT?Excessive?Unrealistic? On the contrary – I believe it to be imperative and inevitable. I honestly hold that, given the range of fatal diseases caused by tobacco use we have little alternative but to pursue the clear objective of creating a tobacco free society. Aiming at a tobacco free society means ensuring public and political opinion are properly informed. It requires help to be given to smokers to break the addiction. It demands that people are protected against environmental tobacco smoke and children are protected from any inducement to experiment with this product. Over the past year we have implemented a number of measures which will support these objectives; we have established an independent Office of Tobacco Control, we have introduced free nicotine replacement therapy for low-income earners, we have extended our existing prohibitions on tobacco advertising to the print media with some minor derogations for international publications. We have raised the legal age at which a person can be sold tobacco products to eighteen years. We have invested substantially more funds in health promotion activities and we have mounted sustained information campaigns. We have engaged in sponsorship arrangements, which are new and innovative for public bodies. I have provided health boards with additional resources to let them mount a sustained inspection and enforcement service. Health boards will engage new Directors of Tobacco Control responsible for coordinating each health board´s response and for liasing with the Tobacco Control Agency I set up earlier this year. Most recently, I have published a comprehensive Bill – The Public Health (Tobacco) Bill, 2001. This Bill will, among other things, end all forms of product display and in-store advertising and will require all retailers to register with the new Tobacco Control Agency. Ten packs of cigarettes will be banned and transparent and independent testing procedures of tobacco products will be introduced. Enforcement officers will be given all the necessary powers to ensure there is full compliance with the law. On smoking in public places we will extend the existing areas covered and it is proposed that I, as Minister for Health and Children, will have the powers to introduce further prohibitions in public places such as pubs and the work place. I will also provide for the establishment of a Tobacco Free Council to advise and assist on an ongoing basis. I believe the measures already introduced and those additional ones proposed in the Bill have widespread community support. In fact, you´re going to hear a detailed presentation from the MRBI which will amply illustrate the extent of this support. The great thing is that the support comes from smokers and non-smokers alike. Bottom line, Ladies and Gentlemen, is that we are at a watershed. As a society (if you´ll allow me to play with a popular phrase) we´ve realised it´s time to ´wake up and smell the cigarettes.´ Smell them. See them for what they are. And get real about destroying their hold on our people. The MRBI survey makes it clear that the single strongest weapon we have when it comes to preventing the habit among young people is price. Simple as that. Price. Up to now, the fear of inflation has been a real impediment to increasing taxes on tobacco. It sounds a serious, logical argument. Until you take it out and look at it a little more closely. Weigh it, as it were, in two hands. I believe – and I believe this with a great passion – that we must take cigarettes out of the equation we use when awarding wage increases. I am calling on IBEC and ICTU, on employers and trade unions alike, to move away from any kind of tolerance of a trade that is killing our citizens. At one point in industrial history, cigarettes were a staple of the workingman´s life. So it was legitimate to include them in the ´basket´ of goods that goes to make up the Consumer Price Index. It isn´t legitimate to include them any more. Today, I´m saying that society collectively must take the step to remove cigarettes from the basket of normality, from the list of elements which constitute necessary consumer spending. I´m saying: “We can no longer delude ourselves. We must exclude cigarettes from the considerations we address in central wage bargaining. We must price cigarettes out of the reach of the children those cigarettes will kill.” Right now, in the monthly Central Statistics Office reports on consumer spending, the figures include cigarettes. But – right down at the bottom of the page – there´s another figure. Calculated without including cigarettes. I believe that if we continue to use the first figure as our constant measure, it will be an indictment of us as legislators, as advocates for working people, as public health professionals. If, on the other hand, we move to the use of the second figure, we will be sending out a message of startling clarity to the nation. We will be saying “We don´t count an addictive, killer drug as part of normal consumer spending.” Taking cigarettes out of the basket used to determine the Consumer Price Index will take away the inflation argument. It will not be easy, in its implications for the social partners. But it is morally inescapable. We must do it. Because it will help us stop the killer that is tobacco. If we can do it, we will give so much extra strength to health educators and the new Tobacco Control Association. This new organisation of young people who already have branches in over fifteen counties, is represented here today. The young adults who make up its membership are well placed to advise children of the dangers of tobacco addiction in a way that older generations cannot. It would strengthen their hand if cigarettes move – in price terms – out of the easy reach of our children Finally, I would like to commend so many public health advocates who have shown professional and indeed personal courage in their commitment to this critical public health issue down through the years. We need you to continue to challenge and confront this grave public health problem and to repudiate the questionable science of the tobacco industry. The Research Institute for a Tobacco Free Society represents a new and dynamic form of partnership between government and civil society. It will provide an effective platform to engage and mobilise the many different professional and academic skills necessary to guide and challenge us. I wish the conference every success.

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Can coeliac consumers enjoy risk-free dining? This project was designed to assess awareness of coeliac condition and to highlight the importance of providing gluten-free food. The survey was conducted in two parts: first, our samplers purchased gluten-free meals from restaurants, and then they completed a questionnaire. This asked questions relating to their purchasing experience and the level of knowledge displayed by restaurant staff. Their whole meal was then dispatched to the laboratory for analysis of the gluten content. Our samplers found that they were able to identify and purchase a gluten-free meal from the restaurants that they visited. While some were supplied with meals that actually contained gluten, the level of gluten in those meals varied considerably. Our samplers ordered 260 meals. Sixteen per cent of these contained gluten, and six and a half per cent were deemed unsatisfactory (containing more than 200mg/kg of gluten). Some of these samples could produce acute illness in coeliac customers. It is likely that the samples with low levels of gluten had been cross-contaminated, while those containing higher levels are more likely to contain some form of gluten in the ingredients. Food service staff rely on advice and input from the chef or manager to recommend and serve a glutenfree meal. Confident staff and well-signposted menu choices do not guarantee risk-free dining for coeliac customers. The survey result supports our view that robust training is required to improve the knowledge of chefs, managers and staff, and help them to manage this hazard. To enable coeliacs to eat out safely and enjoyably, we make the following recommendations

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The number of physical activity measures and indexes used in the human literature is large and may result in some difficulty for the average investigator to choose the most appropriate measure. Accordingly, this review is intended to provide information on the utility and limitations of the various measures. Its primary focus is the objective assessment of free-living physical activity in humans based on physiological and biomechanical methods. The physical activity measures have been classified into three categories: Measures based on energy expenditure or oxygen uptake, such as activity energy expenditure, activity-related time equivalent, physical activity level, physical activity ratio, metabolic equivalent, and a new index of potential interest, daytime physical activity level. Measures based on heart rate monitoring, such as net heart rate, physical activity ratio heart rate, physical activity level heart rate, activity-related time equivalent, and daytime physical activity level heart rate. Measures based on whole-body accelerometry (counts/U time). Quantification of the velocity and duration of displacement in outdoor conditions by satellites using the Differential Global Positioning System may constitute a surrogate for physical activity, because walking is the primary activity of man in free-living conditions. A general outline of the measures and indexes described above is presented in tabular form, along with their respective definition, usual applications, advantages, and shortcomings. A practical example is given with typical values in obese and non-obese subjects. The various factors to be considered in the selection of physical activity methods include experimental goals, sample size, budget, cultural and social/environmental factors, physical burden for the subject, and statistical factors, such as accuracy and precision. It is concluded that no single current technique is able to quantify all aspects of physical activity under free-living conditions, requiring the use of complementary methods. In the future, physical activity sensors, which are of low-cost, small-sized, and convenient for subjects, investigators, and clinicians, are needed to reliably monitor, during extended periods in free-living situations, small changes in movements and grade as well as duration and intensity of typical physical activities.

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In order to raise public awareness of the importance of early detection of airway obstruction and to enable many people who had not been tested previously to have their lung function measured, the European Lung Foundation and the European Respiratory Society (ERS) organised a spirometry testing tent during the annual ERS Congresses in 2004-2009. Spirometry was performed during the ERS Congresses in volunteers; all participants answered a simple, brief questionnaire on their descriptive characteristics, smoking and asthma. Portable spirometers were freely provided by the manufacturer. Nurses and doctors from pulmonary departments of local hospitals/universities gave their service for free. Lower limit of normal (LLN) and Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria for diagnosing and grading airway obstruction were used. Of 12,448 participants in six congress cities, 10,395 (83.5%) performed acceptable spirometry (mean age 51.0 ± 18.4 yrs; 25.5% smokers; 5.5% asthmatic). Airway obstruction was present in 12.4% of investigated subjects according to LLN criteria and 20.3% according to GOLD criteria. Through multinomial logistic regression analysis, age, smoking habits and asthma were significant risk factors for airway obstruction. Relative risk ratio and 95% confidence interval for LLN stage I, for example, was 2.9 (2.0-4.1) for the youngest age (≤ 19 yrs), 1.9 (1.2-3.0) for the oldest age (≥ 80 yrs), 2.4 (2.0-2.9) for current smokers and 2.8 (2.2-3.6) for reported asthma diagnosis. In addition to being a useful advocacy tool, the spirometry tent represents an unusual occasion for early detection of airway obstruction in large numbers of city residents with an important public health perspective.

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AIMS/HYPOTHESIS: The metabolic syndrome comprises a clustering of cardiovascular risk factors but the underlying mechanism is not known. Mice with targeted disruption of endothelial nitric oxide synthase (eNOS) are hypertensive and insulin resistant. We wondered, whether eNOS deficiency in mice is associated with a phenotype mimicking the human metabolic syndrome. METHODS AND RESULTS: In addition to arterial pressure and insulin sensitivity (euglycaemic hyperinsulinaemic clamp), we measured the plasma concentration of leptin, insulin, cholesterol, triglycerides, free fatty acids, fibrinogen and uric acid in 10 to 12 week old eNOS-/- and wild type mice. We also assessed glucose tolerance under basal conditions and following a metabolic stress with a high fat diet. As expected eNOS-/- mice were hypertensive and insulin resistant, as evidenced by fasting hyperinsulinaemia and a roughly 30 percent lower steady state glucose infusion rate during the clamp. eNOS-/- mice had a 1.5 to 2-fold elevation of the cholesterol, triglyceride and free fatty acid plasma concentration. Even though body weight was comparable, the leptin plasma level was 30% higher in eNOS-/- than in wild type mice. Finally, uric acid and fibrinogen were elevated in the eNOS-/- mice. Whereas under basal conditions, glucose tolerance was comparable in knock out and control mice, on a high fat diet, knock out mice became significantly more glucose intolerant than control mice. CONCLUSIONS: A single gene defect, eNOS deficiency, causes a clustering of cardiovascular risk factors in young mice. We speculate that defective nitric oxide synthesis could trigger many of the abnormalities making up the metabolic syndrome in humans.

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Membrane proteins are notoriously difficult to express in a soluble form. Here, we use wheat germ cell-free expression in the presence of various detergents to produce the non-structural membrane proteins 2, 4B and 5A of the hepatitis C virus (HCV). We show that lauryl maltose neopentyl glycol (MNG-3) and dodecyl octaethylene glycol ether (C12E8) detergents can yield essentially soluble membrane proteins at detergent concentrations that do not inhibit the cell-free reaction. This finding can be explained by the low critical micelle concentration (CMC) of these detergents, which keeps the monomer concentrations low while at the same time providing the necessary excess of detergent concentration above CMC required for full target protein solubilization. We estimate that a tenfold excess of detergent micelles with respect to the protein concentration is sufficient for solubilization, a number that we propose as a guideline for detergent screening assays.

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A recurring task in the analysis of mass genome annotation data from high-throughput technologies is the identification of peaks or clusters in a noisy signal profile. Examples of such applications are the definition of promoters on the basis of transcription start site profiles, the mapping of transcription factor binding sites based on ChIP-chip data and the identification of quantitative trait loci (QTL) from whole genome SNP profiles. Input to such an analysis is a set of genome coordinates associated with counts or intensities. The output consists of a discrete number of peaks with respective volumes, extensions and center positions. We have developed for this purpose a flexible one-dimensional clustering tool, called MADAP, which we make available as a web server and as standalone program. A set of parameters enables the user to customize the procedure to a specific problem. The web server, which returns results in textual and graphical form, is useful for small to medium-scale applications, as well as for evaluation and parameter tuning in view of large-scale applications, requiring a local installation. The program written in C++ can be freely downloaded from ftp://ftp.epd.unil.ch/pub/software/unix/madap. The MADAP web server can be accessed at http://www.isrec.isb-sib.ch/madap/.

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A systematic assessment of global neural network connectivity through direct electrophysiological assays has remained technically infeasible, even in simpler systems like dissociated neuronal cultures. We introduce an improved algorithmic approach based on Transfer Entropy to reconstruct structural connectivity from network activity monitored through calcium imaging. We focus in this study on the inference of excitatory synaptic links. Based on information theory, our method requires no prior assumptions on the statistics of neuronal firing and neuronal connections. The performance of our algorithm is benchmarked on surrogate time series of calcium fluorescence generated by the simulated dynamics of a network with known ground-truth topology. We find that the functional network topology revealed by Transfer Entropy depends qualitatively on the time-dependent dynamic state of the network (bursting or non-bursting). Thus by conditioning with respect to the global mean activity, we improve the performance of our method. This allows us to focus the analysis to specific dynamical regimes of the network in which the inferred functional connectivity is shaped by monosynaptic excitatory connections, rather than by collective synchrony. Our method can discriminate between actual causal influences between neurons and spurious non-causal correlations due to light scattering artifacts, which inherently affect the quality of fluorescence imaging. Compared to other reconstruction strategies such as cross-correlation or Granger Causality methods, our method based on improved Transfer Entropy is remarkably more accurate. In particular, it provides a good estimation of the excitatory network clustering coefficient, allowing for discrimination between weakly and strongly clustered topologies. Finally, we demonstrate the applicability of our method to analyses of real recordings of in vitro disinhibited cortical cultures where we suggest that excitatory connections are characterized by an elevated level of clustering compared to a random graph (although not extreme) and can be markedly non-local.

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A laser-based technique for printing transparent and weakly absorbing liquids is developed. Its principle of operation relies in the tight focusing of short laser pulses inside the liquid and close to its free surface, in such a way that the laser radiation is absorbed in a tiny volume around the beam waist, with practically no absorption in any other location along the beam path. If the absorbed energy overcomes the optical breakdown threshold, a cavitation bubble is generated, and its expansion results in the propulsion of a small fraction of liquid which can be collected on a substrate, leading to the printing of a microdroplet for each laser pulse. The technique does not require the preparation of the liquid in thin film form, and its forward mode of operation imposes no restriction concerning the optical properties of the substrate. These characteristics make it well suited for printing a wide variety of materials of interest in diverse applications. We demonstrate that the film-free laser forward printing technique is capable of printing microdroplets with good resolution, reproducibility and control, and analyze the influence of the main process parameter, laser pulse energy. The mechanisms of liquid printing are also investigated: time-resolved imaging provides a clear picture of the dynamics of liquid transfer which allows understanding the main features observed in the printed droplets.