950 resultados para Analysis in tablets


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This paper analyzes the role of the energy transformation index and of final energy consumption per GDP unit in the disparities in energy intensity across countries. In that vein, we use a Theil decomposition approach to analyze global primary energy intensity inequality as well as inequality across different regions of the world and inequality within these regions. The paper first demonstrates the pre-eminence of divergence in final energy consumption per GDP unit in explaining global primary energy intensity inequality and its evolution during the 1971-2006 period. Secondly, it shows the lower (albeit non negligible) impact of the transformation index in global primary energy inequality. Thirdly, the relevance of regions as unit of analysis in studying crosscountry energy intensity inequality and their explanatory factors is highlighted. And finally, how regions around the world differ as to the relevance of the energy transformation index in explaining primary energy intensity inequality.

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Integrative and conjugative elements (ICE) are in some ways parasitic mobile DNA that propagate vertically through replication with the bacterial host chromosome but at low frequencies can excise and invade new recipient cells through conjugation and reintegration (horizontal propagation). The factors that contribute to successful horizontal propagation are not very well understood. Here, we study the influence of host cell life history on the initiation of transfer of a model ICE named ICEclc in bacteria of the genus Pseudomonas. We use time-lapse microscopy of growing and stationary-phase microcolonies of ICEclc bearing cells in combination with physiological staining and gene reporter analysis in stationary-phase suspended cells. We provide evidence that cell age and cell lineage are unlikely to play a role in the decision to initiate the ICEclc transfer program. In contrast, cells activating ICEclc show more often increased levels of reactive oxygen species and membrane damage than nonactivating cells, suggesting that some form of biochemical damage may make cells more prone to ICEclc induction. Finally, we find that ICEclc active cells appear spatially at random in a microcolony, which may have been a selective advantage for maximizing ICEclc horizontal transmission to new recipient species.

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Background: Hirschsprung disease is characterized by the absence of intramural ganglion cells in the enteric plexuses, due to a fail during enteric nervous system formation. Hirschsprung has a complex genetic aetiology and mutations in several genes have been related to the disease. There is a clear predominance of missense/nonsense mutations in these genes whereas copy number variations (CNVs) have been seldom described, probably due to the limitations of conventional techniques usually employed for mutational analysis. In this study, we have looked for CNVs in some of the genes related to Hirschsprung (EDNRB, GFRA1, NRTN and PHOX2B) using the Multiple Ligation-dependent Probe Amplification (MLPA) approach. Methods: CNVs screening was performed in 208 HSCR patients using a self-designed set of MLPA probes, covering the coding region of those genes. Results: A deletion comprising the first 4 exons in GFRA1 gene was detected in 2 sporadic HSCR patients and in silico approaches have shown that the critical translation initiation signal in the mutant gene was abolished. In this study, we have been able to validate the reliability of this technique for CNVs screening in HSCR. Conclusions: The implemented MLPA based technique presented here allows CNV analysis of genes involved in HSCR that have not been not previously evaluated. Our results indicate that CNVs could be implicated in the pathogenesis of HSCR, although they seem to be an uncommon molecular cause of HSCR.

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Black-box optimization problems (BBOP) are de ned as those optimization problems in which the objective function does not have an algebraic expression, but it is the output of a system (usually a computer program). This paper is focussed on BBOPs that arise in the eld of insurance, and more speci cally in reinsurance problems. In this area, the complexity of the models and assumptions considered to de ne the reinsurance rules and conditions produces hard black-box optimization problems, that must be solved in order to obtain the optimal output of the reinsurance. The application of traditional optimization approaches is not possible in BBOP, so new computational paradigms must be applied to solve these problems. In this paper we show the performance of two evolutionary-based techniques (Evolutionary Programming and Particle Swarm Optimization). We provide an analysis in three BBOP in reinsurance, where the evolutionary-based approaches exhibit an excellent behaviour, nding the optimal solution within a fraction of the computational cost used by inspection or enumeration methods.

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This preliminary exploration was limited by a number of factors. The format of the study has necessarily induced some form of selection bias of the panelists, because of the complexity of some questions, and the time required to complete the questionnaires. Several issues have not been addressed. One example could be the response to HIV infection occurring in a vaccinee. The study also did not address the difficulties related to the licensing of the vaccine. Indeed, the proposed scenario assumed that the vaccine had been registered as a starting point for the analysis. Finally, it has not been possible to conduct a sensitivity analysis, in order to evaluate how the responses would have been modified if some important characteristics of the vaccine had been modified.Very diverse evaluations were given in response to questions related with attitudes and perception of AIDS and AIDS vaccine. The possibility that vaccine availability or usage can be associated with an increased frequency in risky behaviors was spontaneously mentioned by half of the panelists. The estimation of the proportion of persons at highest risk who would choose to use this vaccine also indicated a high degree of uncertainty. This study offers important lessons. According to a broad and diverse panel of individuals, an incompletely effective AIDS vaccine would result in an additional level of complexity for the AIDS prevention strategy, rather than a simplification. The use of such a vaccine would have to be coupled with counselling. This implies a sustained emphasis on the recommendations which have been central to the STOP AIDS campaigns until now. In addition, consensual issues, as well as other issues more likely to be controversial have been identified. This should greatly help focusing the work of any committee designated to develop and implement a vaccination policy if an AIDS vaccine became available. Finally, our experience with the Policy Delphi indicates that this mode of structured communication could be usefully applied to other public health issues presenting a high visibility as well as a complex relationship with public perception.

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The aim of this study was to assess whether Neisseria meningitidis, Listeria monocytogenes, Streptococcus pneumoniae and Haemophilus influenzae can be identified using the polymerase chain reaction technique in the cerebrospinal fluid of severely decomposed bodies with known, noninfectious causes of death or whether postmortem changes can lead to false positive results and thus erroneous diagnostic information. Biochemical investigations, postmortem bacteriology and real-time polymerase chain reaction analysis in cerebrospinal fluid were performed in a series of medico-legal autopsies that included noninfectious causes of death with decomposition, bacterial meningitis without decomposition, bacterial meningitis with decomposition, low respiratory tract infections with decomposition and abdominal infections with decomposition. In noninfectious causes of death with decomposition, postmortem investigations failed to reveal results consistent with generalized inflammation or bacterial infections at the time of death. Real-time polymerase chain reaction analysis in cerebrospinal fluid did not identify the studied bacteria in any of these cases. The results of this study highlight the usefulness of molecular approaches in bacteriology as well as the use of alternative biological samples in postmortem biochemistry in order to obtain suitable information even in corpses with severe decompositional changes.

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A citation analysis was carried out on the most important research journals in the field of Catalan literature between 1974 and 2003. The indicators and qualitative parameters obtained show the value of performing citation analysis in cultural and linguistic areas that are poorly covered by the A&HCI. Catalan literature shows a similar pattern to that of humanities in general, but it could still be in a stage of consolidation because too little work has as yet been published.

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The objective of this study was to evaluate the efficiency of spatial statistical analysis in the selection of genotypes in a plant breeding program and, particularly, to demonstrate the benefits of the approach when experimental observations are not spatially independent. The basic material of this study was a yield trial of soybean lines, with five check varieties (of fixed effect) and 110 test lines (of random effects), in an augmented block design. The spatial analysis used a random field linear model (RFML), with a covariance function estimated from the residuals of the analysis considering independent errors. Results showed a residual autocorrelation of significant magnitude and extension (range), which allowed a better discrimination among genotypes (increase of the power of statistical tests, reduction in the standard errors of estimates and predictors, and a greater amplitude of predictor values) when the spatial analysis was applied. Furthermore, the spatial analysis led to a different ranking of the genetic materials, in comparison with the non-spatial analysis, and a selection less influenced by local variation effects was obtained.

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Using Swiss data from the 2003 International Social Survey Programme (N = 902), this multilevel study combined individual and municipality levels of analysis in the explanation of nationalism, patriotism and exclusionary immigration attitudes. On the individual level, the results show that in line with previous research nationalism (uncritical and blind attachment to the nation) increased exclusionary immigration attitudes, while patriotism (pride in national democratic institutions) was related to greater tolerance towards immigration. On the municipality level, urbanization, socioeconomic status and immigrant proportion (and their interaction effects) were found to affect nationalism, patriotism and immigration attitudes. Nationalist and patriotic forms of national attachment were stronger in German-speaking municipalities than in the French-speaking municipalities. Path analyses further revealed that living in a Swiss-German municipality indirectly led to more negative immigration attitudes through an increase in nationalism. The research is discussed in light of social psychological and political science literature on political attitudes.

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Fytoestrogeenit ovat kasvimateriaalista peräisin olevia yhdisteitä, joilla on ihmisen estrogeeni-hormonin kaltaista aktiivisuutta. Fytoestrogeenit voidaan jakaa kolmeen pääryhmään, joista yksi merkittävä ryhmä on lignaanit. Lignaaneilla on todettu olevan antioxidatiivisia, antiviraalisia ja antibakteriaalisia ominaisuuksia. Niillä on todettu olevan myös positiivisia vaikutuksia hormoniperäisten syöpien ehkäisyssä. Näiden ominaisuuksien vuoksi lignaaneja pyritään hyödyntämään esimerkiksi aktiivisina ainesosina funktionaalisissa elintarvikkeissa. Tässä työssä tutkittiin lignaanin, hydroksimatairesinolin (HMRlignanTM) kemiallisia ominaisuuksia ja soveltuvuutta eri ruoka-aineisiin. Työn tarkoituksena oli selvittää ruoka-aineisiin lisätyn hydroksimatairesinolin kemiallista pysyvyyttä erilaisissa säilytys- ja prosessointioloissa sekä tutkia lignaanin liukoisuutta erilaisiin liuottimiin. Hydroksimatairesinolin analysoimiseksi ruoka-aineista käytettiin korkean erotuskyvyn omaavaa nestekromatografista menetelmää. Menetelmä validoitiin ennen varsinaista analysointia ICH-ohjeiston mukaisesti. Validoinnissa tutkittiin kromatografiamenetelmän spesifisyys, lineaarisuus, tarkkuus, oikeellisuus sekä detektointi- ja määritysrajat tutkittavalle lignaanille. Käytetty menetelmä soveltui hyvin lignaanin analysoimiseen ruoka-aineista. Hydroksimatairesinolin vesiliukoisuuden todettiin olevan noin 1 mg/ml. Tutkimukset osoittivat hydroksimatairesinolin olevan stabiili alle 50ºC:en lämpötiloissa. Korkeammissa lämpötiloissa hydroksimatairesinoli oli stabiili jauhemuodossa lisättynä.

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Genome-wide association studies (GWASs) have identified many genetic variants underlying complex traits. Many detected genetic loci harbor variants that associate with multiple-even distinct-traits. Most current analysis approaches focus on single traits, even though the final results from multiple traits are evaluated together. Such approaches miss the opportunity to systemically integrate the phenome-wide data available for genetic association analysis. In this study, we propose a general approach that can integrate association evidence from summary statistics of multiple traits, either correlated, independent, continuous, or binary traits, which might come from the same or different studies. We allow for trait heterogeneity effects. Population structure and cryptic relatedness can also be controlled. Our simulations suggest that the proposed method has improved statistical power over single-trait analysis in most of the cases we studied. We applied our method to the Continental Origins and Genetic Epidemiology Network (COGENT) African ancestry samples for three blood pressure traits and identified four loci (CHIC2, HOXA-EVX1, IGFBP1/IGFBP3, and CDH17; p < 5.0 × 10(-8)) associated with hypertension-related traits that were missed by a single-trait analysis in the original report. Six additional loci with suggestive association evidence (p < 5.0 × 10(-7)) were also observed, including CACNA1D and WNT3. Our study strongly suggests that analyzing multiple phenotypes can improve statistical power and that such analysis can be executed with the summary statistics from GWASs. Our method also provides a way to study a cross phenotype (CP) association by using summary statistics from GWASs of multiple phenotypes.

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Needle trap devices (NTDs) are a relatively new and promising tool for headspace (HS) analysis. In this study, a dynamic HS sampling procedure is evaluated for the determination of volatile organic compounds (VOCs) in whole blood samples. A full factorial design was used to evaluate the influence of the number of cycles and incubation time and it is demonstrated that the controlling factor in the process is the number of cycles. A mathematical model can be used to determine the most appropriate number of cycles required to adsorb a prefixed amount of VOCs present in the HS phase whenever quantitative adsorption is reached in each cycle. Matrix effect is of great importance when complex biological samples, such as blood, are analyzed. The evaluation of the salting out effect showed a significant improvement in the volatilization of VOCs to the HS in this type of matrices. Moreover, a 1:4 (blood:water) dilution is required to obtain quantitative recoveries of the target analytes when external calibration is used. The method developed gives detection limits in the 0.020–0.080 μg L−1 range (0.1–0.4 μg L−1 range for undiluted blood samples) with appropriate repeatability values (RSD < 15% at high level and <23% at LOQ level). Figure of merits of the method can be improved by using a smaller phase ratio (i.e., an increase in the blood volume and a decrease in the HS volume), which lead to lower detection limits, better repeatability values and greater sensibility. Twenty-eight blood samples have been evaluated with the proposed method and the results agree with those indicated in other studies. Benzene was the only target compound that gave significant differences between blood levels detected in volunteer non-smokers and smokers

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There is an increasing interest in the use of breath analysis for monitoring human physiology and exposure to toxic substances or environmental pollutants. This review focuses on the current status of the sampling procedures, collection devices and sample-enrichment methodologies used for exhaled breath-vapor analysis. We discuss the different parameters affecting each of the above steps, taking into account the requirements for breath analysis in exposure assessments and the need to analyze target compounds at sub-ppbv levels. Finally, we summarize the practical applications of exposure analysis in the past two decades

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Hip fractures are associated with significant morbidity and mortality. Cervical and trochanteric fractures have a different morphometry, surgical treatment, and outcome. Polypharmacy, common in older people, is associated with increased mortality. The risk factors for mortality can be identified based on cause-of-death analysis. In this population-based study, 461 older, surgically in 1999-2000 treated hip fracture patients were enrolled. Incidence, morphometry, medication, mortality, and cause-of-death were analysed. Hip fractures were most commonly sustained by women, occurred mostly indoors, and often in institutions. One in four patients had sustained a previous fracture. Routine clinical radiographs revealed no differences in the hip geometry between hip fracture types. Age-adjusted mortality was higher in men than in women during the follow-up. Chronic lung disease and male sex were predictors of mortality after cervical fracture. In men, potent anticholinergics were associated with excess age-adjusted mortality. Men were more likely to die from circulatory disease and dementia after hip fracture than women. Mortality after hip fracture was 3-fold higher than that of the general population, including every cause-of-death class. Fracture prevention in institutions and homes, indoor safety measures, and treatment of chronic lung diseases should be encouraged. Hip morphometry analyses require more accurate measures than that provided by routine radiographs. Careful use of potent anticholinergics may reduce mortality. Compared to the general population, excess mortality after hip fracture was evident up to 9 years after hip fracture. Cause-of-death analysis indicates that all major comorbidities require optimal treatment after hip fracture surgery.

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The amount of installed wind power has been growing exponentially during the past ten years. As wind turbines have become a significant source of electrical energy, the interactions between the turbines and the electric power network need to be studied more thoroughly than before. Especially, the behavior of the turbines in fault situations is of prime importance; simply disconnecting all wind turbines from the network during a voltage drop is no longer acceptable, since this would contribute to a total network collapse. These requirements have been a contributor to the increased role of simulations in the study and design of the electric drive train of a wind turbine. When planning a wind power investment, the selection of the site and the turbine are crucial for the economic feasibility of the installation. Economic feasibility, on the other hand, is the factor that determines whether or not investment in wind power will continue, contributing to green electricity production and reduction of emissions. In the selection of the installation site and the turbine (siting and site matching), the properties of the electric drive train of the planned turbine have so far been generally not been taken into account. Additionally, although the loss minimization of some of the individual components of the drive train has been studied, the drive train as a whole has received less attention. Furthermore, as a wind turbine will typically operate at a power level lower than the nominal most of the time, efficiency analysis in the nominal operating point is not sufficient. This doctoral dissertation attempts to combine the two aforementioned areas of interest by studying the applicability of time domain simulations in the analysis of the economicfeasibility of a wind turbine. The utilization of a general-purpose time domain simulator, otherwise applied to the study of network interactions and control systems, in the economic analysis of the wind energy conversion system is studied. The main benefits of the simulation-based method over traditional methods based on analytic calculation of losses include the ability to reuse and recombine existing models, the ability to analyze interactions between the components and subsystems in the electric drive train (something which is impossible when considering different subsystems as independent blocks, as is commonly done in theanalytical calculation of efficiencies), the ability to analyze in a rather straightforward manner the effect of selections other than physical components, for example control algorithms, and the ability to verify assumptions of the effects of a particular design change on the efficiency of the whole system. Based on the work, it can be concluded that differences between two configurations can be seen in the economic performance with only minor modifications to the simulation models used in the network interaction and control method study. This eliminates the need ofdeveloping analytic expressions for losses and enables the study of the system as a whole instead of modeling it as series connection of independent blocks with no lossinterdependencies. Three example cases (site matching, component selection, control principle selection) are provided to illustrate the usage of the approach and analyze its performance.