907 resultados para Mixed model under selection


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Introduction: Kinesio Taping (KT) has been used in healthy people to improve neuromuscular performance, however, few studies have evaluated its chronic effects, despite being suggested. Objective: To analyze the chronic effects of KT on neuromuscular performance of the quadriceps, the oscillation of the center of pressure and lower limb function in healthy women. Methods: blinded, randomized, controlled trial, composed of 60 women (mean age 21.9 ± 3.3 years and BMI 22.3 ± 2.2 kg / m2) submitted to the evaluation of oscillation of the center of pressure through the baropodometry, the lower limb function by the hop test, isokinetic knee performance, the electromyographic activity of the vastus lateralis (VL) and joint position sense of the knee (JPS). Then, participants were randomly divided into three groups of twenty: control - did not apply the KT; placebo - application of KT without tension on the quadriceps; Kinesio Taping - application of KT with tension in the same muscle group. The evaluations were conducted in five moments: prior to application of KT, immediately after the application, 24h, 48h after application and 24 hours after its removal (72h). SPSS 20.0 was used for statistical analysis. The KS test was used to verify the data normality, the Levene test for homogeneity of variances and a mixed-model ANOVA 3x5 to check intra and inter-group differences. Results: there was no difference in peak torque, the power, nor the electromyographic activity or SPA (p> 0.05) between groups. The displacement speed of center of pressure reduced immediately after the application on kinesio taping group (p <0.001), but with no differences between the groups (p = 0.28). There was a reduction in the time of peak torque among the three groups in the evaluations after KT application (p <0.001) and an increase in single hop in all groups (p <0.001), but with no differences between them. Conclusion: KT can not change, in a chronic way, the lower limb function, the oscillation of the center of pressure, the isokinetic performance, the JPS of the knee and the electromyographic activity of VL muscle in healthy women.

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This work consists basically in the elaboration of an Artificial Neural Network (ANN) in order to model the composites materials’ behavior when submitted to fatigue loadings. The proposal is to develop and present a mixed model, which associate an analytical equation (Adam Equation) to the structure of the ANN. Given that the composites often shows a similar behavior when subject to float loadings, this equation aims to establish a pre-defined comparison pattern for a generic material, so that the ANN fit the behavior of another composite material to that pattern. In this way, the ANN did not need to fully learn the behavior of a determined material, because the Adam Equation would do the big part of the job. This model was used in two different network architectures, modular and perceptron, with the aim of analyze it efficiency in distinct structures. Beyond the different architectures, it was analyzed the answers generated from two sets of different data – with three and two SN curves. This model was also compared to the specialized literature results, which use a conventional structure of ANN. The results consist in analyze and compare some characteristics like generalization capacity, robustness and the Goodman Diagrams, developed by the networks.

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Objective: analyze the effect of Kinesio Taping (KT) on the indirect clinical markers of muscle damage induced by eccentric exercises in the elbow flexors in healthy individuals. Materials and methods: It is a randomized controlled trial involving sixty volunteers at age group between 18 and 28 years randomly selected. The sample into three groups with twenty participants: control group (CG) – eccentric protocol without KT, KT group – eccentric with tensioned KT, placebo group – eccentric protocol KT with no tension. The evaluations took place at four moments; the first one was the basis line (AV1), after the second protocol (AV2) and the following two groups 24 (AV3) and 48 hours (AV4) after the intervention protocol. The muscle damage was induced by sixteen maximum eccentric contractions of the elbow flexors from the non-dominant limb, divided in two sets of eight repetitions, at 60º/s, with two minutes interval. The variables analyzed were: the joint amplitude in rest, the level of pain, the joint position sense (JPS) followed of isokinetic checking with electromyographic sign capitation. These data were analyzed in software SPSS 20.0. The normality was identified by Kolmogorov-Smimov examination and then, being used the ANOVA mixed model with significance of 5%. Outcomes: a decrease was observed at joint amplitude moreover, an immediate increase of pain wich increased after 24 and remained until 48 hours at all groups searched. There was not difference at the JPS. The variables peak torque, average peak torque, total work and mean power mean reduced until 48 hours after muscle lesion in all groups. Among the groups, there was no difference in EMG values and for any of the variables. Conclusion: The KT did not influence at the indirect clinical markers of muscle lesion induced by eccentric exercises in the elbow flexors in healthy people.

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Objective: analyze the effect of Kinesio Taping (KT) on the indirect clinical markers of muscle damage induced by eccentric exercises in the elbow flexors in healthy individuals. Materials and methods: It is a randomized controlled trial involving sixty volunteers at age group between 18 and 28 years randomly selected. The sample into three groups with twenty participants: control group (CG) – eccentric protocol without KT, KT group – eccentric with tensioned KT, placebo group – eccentric protocol KT with no tension. The evaluations took place at four moments; the first one was the basis line (AV1), after the second protocol (AV2) and the following two groups 24 (AV3) and 48 hours (AV4) after the intervention protocol. The muscle damage was induced by sixteen maximum eccentric contractions of the elbow flexors from the non-dominant limb, divided in two sets of eight repetitions, at 60º/s, with two minutes interval. The variables analyzed were: the joint amplitude in rest, the level of pain, the joint position sense (JPS) followed of isokinetic checking with electromyographic sign capitation. These data were analyzed in software SPSS 20.0. The normality was identified by Kolmogorov-Smimov examination and then, being used the ANOVA mixed model with significance of 5%. Outcomes: a decrease was observed at joint amplitude moreover, an immediate increase of pain wich increased after 24 and remained until 48 hours at all groups searched. There was not difference at the JPS. The variables peak torque, average peak torque, total work and mean power mean reduced until 48 hours after muscle lesion in all groups. Among the groups, there was no difference in EMG values and for any of the variables. Conclusion: The KT did not influence at the indirect clinical markers of muscle lesion induced by eccentric exercises in the elbow flexors in healthy people.

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Objective: to investigate the immediate effect of the vibrating platform on the neuromuscular performance of the quadriceps femoris and on the postural oscillation of subjects submitted to Anterior Cruciate Ligament (ACL) reconstruction. Materials and methods: this study is a randomized and blind clinical trial. Forty-four male volunteers (average age of 27,4 ±6,2 IMC of 26,85± 3,8 Kg/m² and post surgery timeframe of 17± 1,4 weeks) were randomized into two groups: OFF platform (n=22, protocol of exercise over the vibrating platform off) and ON platform (n=22 protocol of exercise over the vibrating platform on, 50Hz frequency and 4mm of amplitude). All volunteers were submitted to assessment the isokinetic evaluation of the quadriceps femoris (isometric and isokinetic at 60°/s) and of the electromyography activity of the muscles Vasto Lateralis (VL) and Vasto Medialis (VM), besides the postural oscillation (baropodometry) in two distinct moments: before and immediately after the intervention protocol. The data was analyzed through the SPSS 20.0 software, with a 5% significance level. To verify the homogeneity of the groups it was used an ANOVA one way, and a ANOVA mixed model to compare the intra and inter groups. Results: it was observed differences between the pre and the post, to latero lateral velocity, isometric torque peak and total work in comparison with intragroup. However, it wasn’t verified any difference in comparing the intergroup in the preevaluation and in the post-evaluation protocol over the vibrating platform. Conclusion: the use of the vibrating platform doesn’t change as an immediate manner the isokinetic performance of the quadriceps femoris, the electromyography activity of the VL and the VM, also doesn’t interfere with the postural oscillation of individuals that were submitted to the ACL reconstruction.

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In this thesis, research for tsunami remote sensing using the Global Navigation Satellite System-Reflectometry (GNSS-R) delay-Doppler maps (DDMs) is presented. Firstly, a process for simulating GNSS-R DDMs of a tsunami-dominated sea sur- face is described. In this method, the bistatic scattering Zavorotny-Voronovich (Z-V) model, the sea surface mean square slope model of Cox and Munk, and the tsunami- induced wind perturbation model are employed. The feasibility of the Cox and Munk model under a tsunami scenario is examined by comparing the Cox and Munk model- based scattering coefficient with the Jason-1 measurement. A good consistency be- tween these two results is obtained with a correlation coefficient of 0.93. After con- firming the applicability of the Cox and Munk model for a tsunami-dominated sea, this work provides the simulations of the scattering coefficient distribution and the corresponding DDMs of a fixed region of interest before and during the tsunami. Fur- thermore, by subtracting the simulation results that are free of tsunami from those with presence of tsunami, the tsunami-induced variations in scattering coefficients and DDMs can be clearly observed. Secondly, a scheme to detect tsunamis and estimate tsunami parameters from such tsunami-dominant sea surface DDMs is developed. As a first step, a procedure to de- termine tsunami-induced sea surface height anomalies (SSHAs) from DDMs is demon- strated and a tsunami detection precept is proposed. Subsequently, the tsunami parameters (wave amplitude, direction and speed of propagation, wavelength, and the tsunami source location) are estimated based upon the detected tsunami-induced SSHAs. In application, the sea surface scattering coefficients are unambiguously re- trieved by employing the spatial integration approach (SIA) and the dual-antenna technique. Next, the effective wind speed distribution can be restored from the scat- tering coefficients. Assuming all DDMs are of a tsunami-dominated sea surface, the tsunami-induced SSHAs can be derived with the knowledge of background wind speed distribution. In addition, the SSHA distribution resulting from the tsunami-free DDM (which is supposed to be zero) is considered as an error map introduced during the overall retrieving stage and is utilized to mitigate such errors from influencing sub- sequent SSHA results. In particular, a tsunami detection procedure is conducted to judge the SSHAs to be truly tsunami-induced or not through a fitting process, which makes it possible to decrease the false alarm. After this step, tsunami parameter estimation is proceeded based upon the fitted results in the former tsunami detec- tion procedure. Moreover, an additional method is proposed for estimating tsunami propagation velocity and is believed to be more desirable in real-world scenarios. The above-mentioned tsunami-dominated sea surface DDM simulation, tsunami detection precept and parameter estimation have been tested with simulated data based on the 2004 Sumatra-Andaman tsunami event.

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El 5º Informe del IPCC (Panel Intergubernamental de Cambio Climático, 2014) señala que el turismo será una de las actividades económicas que mayores efectos negativos experimentará en las próximas décadas debido al calentamiento térmico del planeta. En España, el turismo es una fuente principal de ingresos y de creación de puestos de trabajo en su economía. De ahí que sea necesaria la puesta en marcha de medidas de adaptación a la nueva realidad climática que, en nuestro país, va a suponer cambios en el confort climático de los destinos e incremento de extremos atmosféricos. Frente a los planes de adaptación al cambio climático en la actividad turística, elaborados por los gobiernos estatal y regional, que apenas se han desarrollado en España, la escala local muestra interesantes ejemplos de acciones de adaptación al cambio climático, desarrolladas tanto por los municipios (energía, transporte, vivienda, planificación urbanística) como por la propia empresa turística (hoteles, campings, apartamentos). Medidas de ahorro de agua y luz, fomento del transporte público y de las energías limpias, creación de zonas verdes urbanas y adaptación a los extremos atmosféricos destacan como acciones de mitigación del cambio climático en los destinos turísticos principales de nuestro país.

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We hypothesize that at least some of the recently discovered class of calcium-rich gap transients are tidal detonation events of white dwarfs (WDs) by black holes (BHs) or possibly neutron stars. We show that the properties of the calcium-rich gap transients agree well with the predictions of the tidal detonation model. Under the predictions of this model, we use a follow-up X-ray observation of one of these transients, SN 2012hn, to place weak upper limits on the detonator mass of this system that include all intermediate-mass BHs (IMBHs). As these transients are preferentially in the stellar haloes of galaxies, we discuss the possibility that these transients are tidal detonations of WDs caused by random flyby encounters with IMBHs in dwarf galaxies or globular clusters. This possibility has been already suggested in the literature but without connection to the calcium-rich gap transients. In order for the random flyby cross-section to be high enough, these events would have to be occurring inside these dense stellar associations. However, there is a lack of evidence for IMBHs in these systems, and recent observations have ruled out all but the very faintest dwarf galaxies and globular clusters for a few of these transients. Another possibility is that these are tidal detonations caused by three-body interactions, where a WD is perturbed towards the detonator in isolated multiple star systems. We highlight a number of ways this could occur, even in lower mass systems with stellar-mass BHs or neutron stars. Finally, we outline several new observational tests of this scenario, which are feasible with current instrumentation.

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Robust joint modelling is an emerging field of research. Through the advancements in electronic patient healthcare records, the popularly of joint modelling approaches has grown rapidly in recent years providing simultaneous analysis of longitudinal and survival data. This research advances previous work through the development of a novel robust joint modelling methodology for one of the most common types of standard joint models, that which links a linear mixed model with a Cox proportional hazards model. Through t-distributional assumptions, longitudinal outliers are accommodated with their detrimental impact being down weighed and thus providing more efficient and reliable estimates. The robust joint modelling technique and its major benefits are showcased through the analysis of Northern Irish end stage renal disease patients. With an ageing population and growing prevalence of chronic kidney disease within the United Kingdom, there is a pressing demand to investigate the detrimental relationship between the changing haemoglobin levels of haemodialysis patients and their survival. As outliers within the NI renal data were found to have significantly worse survival, identification of outlying individuals through robust joint modelling may aid nephrologists to improve patient's survival. A simulation study was also undertaken to explore the difference between robust and standard joint models in the presence of increasing proportions and extremity of longitudinal outliers. More efficient and reliable estimates were obtained by robust joint models with increasing contrast between the robust and standard joint models when a greater proportion of more extreme outliers are present. Through illustration of the gains in efficiency and reliability of parameters when outliers exist, the potential of robust joint modelling is evident. The research presented in this thesis highlights the benefits and stresses the need to utilise a more robust approach to joint modelling in the presence of longitudinal outliers.

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A presente investigação examina o papel da inteligêncial emocional (IE) no desempenho académico, numa amostra de 111 estudantes em frequência do ensino universitário português. No presente trabalho faz-se uma revisão bibliográfica do tema da IE e dos factores contributivos para o desempenho académico, bem como uma breve visita a outros trabalhos desenvolvidos nesta área de investigação. Para medição da IE assumiu-se o modelo misto, tendo-se avaliado as seguintes seis dimensões: 1) auto-encorajamento (uso das emoções); 2) compreensão das emoções próprias; 3) autocontrolo perante as críticas; 4)compreensão das emoções dos outros; 5) empatia e contágio emocional; 6) autocontrolo emocional (regulação das emoções). O desempenho académico foi calculado a partir das médias das classificações obtidas pelos estudantes no final do primeiro semestre do ano lectivo 2009/2010. Os resultados evidenciam que os alunos com melhores desempenhos académicos denotam níveis superiores de inteligência emocional, se bem que não foram encontradas associações significativas entre a IE e o desempenho académico, sugerindo a necessidade de mais estudos com vista ao aprofundamento desta jovem e controversa área de pesquisa. / The research investigates the role of emotional intelligence (EI)in academic achivement in a sample of 111 students that attend Portuguese universities. In this work we review the issue of EI and the factors that contibute to academic achievement, at the same time making a brief visit to other works done on this area. In order to measure EI, the mixed model was used, evaluating through the following six dimensions: 1) self-encouragement (use of emotions); 2) understanding of self emotions; 3) self-control in response to criticism; 4) understanding of emotions in others; 5) empathy and emotional contagion; 6) emotional self-control (regulation of emotions). Academic achievement was evaluated by the average of the grades obtained by the students at the end of the first semester of the academic year 2009/2010. The results show that students with better academic outcomes demonstrate higher emotional intelligence, though there were no significative associations between EI and academic achievement, suggesting the need for further studies in order to deepen this young and controversial area of research.

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1. Genomewide association studies (GWAS) enable detailed dissections of the genetic basis for organisms' ability to adapt to a changing environment. In long-term studies of natural populations, individuals are often marked at one point in their life and then repeatedly recaptured. It is therefore essential that a method for GWAS includes the process of repeated sampling. In a GWAS, the effects of thousands of single-nucleotide polymorphisms (SNPs) need to be fitted and any model development is constrained by the computational requirements. A method is therefore required that can fit a highly hierarchical model and at the same time is computationally fast enough to be useful. 2. Our method fits fixed SNP effects in a linear mixed model that can include both random polygenic effects and permanent environmental effects. In this way, the model can correct for population structure and model repeated measures. The covariance structure of the linear mixed model is first estimated and subsequently used in a generalized least squares setting to fit the SNP effects. The method was evaluated in a simulation study based on observed genotypes from a long-term study of collared flycatchers in Sweden. 3. The method we present here was successful in estimating permanent environmental effects from simulated repeated measures data. Additionally, we found that especially for variable phenotypes having large variation between years, the repeated measurements model has a substantial increase in power compared to a model using average phenotypes as a response. 4. The method is available in the R package RepeatABEL. It increases the power in GWAS having repeated measures, especially for long-term studies of natural populations, and the R implementation is expected to facilitate modelling of longitudinal data for studies of both animal and human populations.

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The discussions wherein develop proposals for university reform in Brazil include, among other things, the conception of the university titled "New University", whose structural origin comes from the bill of higher education reform and unification of the foundations of education European upper (Bologna process). At its core, the Bologna process has imposed a series of transformations, among which, the promotion of mobility, as a stimulus to interinstitutional cooperation to enable an better and bigger qualification of the students. Nevertheless, what we see is that this point is one of the main points made flawed by Brazilian institutions that have adopted this model of higher education. An example is the Bachelor of Science and Technology - BC&T, Federal University of Rio Grande do Norte - UFRN, where there are problems of the internal order, represented by the problem of the reusing of the disciplines, such also of external order, in cases of transfers interinstitutional. Because of this, and knowing that this is a typical problem in which multiple criteria are involved, the aim of this study is to propose a multicriteria model for selection of interciclo of the BC&T of the UFRN which addresses the issue of mobility. For this, this study was of exploratory and study case nature, use as tools of data collection, the bibliographic and documentary research, as well as semi-structured interviews. For the elaboration of the model, were used the five phases most commonly used in the modeling of problems in operational research in a sample of 91 students of BC&T. As a result, we obtained a model that addresses the issue of internal and external mobility of the school and that, moreover, was also more robust and fair than the current model of BC&T and also what is used in other courses of the UFRN, taking into consideration the expected results by the decision makers

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The cytokine hormone leptin is a key signalling molecule in many pathways that control physiological functions. Although leptin demonstrates structural conservation in mammals, there is evidence of positive selection in primates, lagomorphs and chiropterans. We previously reported that the leptin genes of the grey and harbour seals (phocids) have significantly diverged from other mammals. Therefore we further investigated the diversification of leptin in phocids, other marine mammals and terrestrial taxa by sequencing the leptin genes of representative species. Phylogenetic reconstruction revealed that leptin diversification was pronounced within the phocid seals with a high dN/dS ratio of 2.8, indicating positive selection. We found significant evidence of positive selection along the branch leading to the phocids, within the phocid clade, but not over the dataset as a whole. Structural predictions indicate that the individual residues under selection are away from the leptin receptor (LEPR) binding site. Predictions of the surface electrostatic potential indicate that phocid seal leptin is notably different to other mammalian leptins, including the otariids. Cloning the grey seal leptin binding domain of LEPR confirmed that this was structurally conserved. These data, viewed in toto, support a hypothesis that phocid leptin divergence is unlikely to have arisen by random mutation. Based upon these phylogenetic and structural assessments, and considering the comparative physiology and varying life histories among species, we postulate that the unique phocid diving behaviour has produced this selection pressure. The Phocidae includes some of the deepest diving species, yet have the least modified lung structure to cope with pressure and volume changes experienced at depth. Therefore, greater surfactant production is required to facilitate rapid lung re-inflation upon surfacing, while maintaining patent airways. We suggest that this additional surfactant requirement is met by the leptin pulmonary surfactant production pathway which normally appears only to function in the mammalian foetus.

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Modern automobiles are no longer just mechanical tools. The electronics and computing services they are shipping with are making them not less than a computer. They are massive kinetic devices with sophisticated computing power. Most of the modern vehicles are made with the added connectivity in mind which may be vulnerable to outside attack. Researchers have shown that it is possible to infiltrate into a vehicle’s internal system remotely and control the physical entities such as steering and brakes. It is quite possible to experience such attacks on a moving vehicle and unable to use the controls. These massive connected computers can be life threatening as they are related to everyday lifestyle. First part of this research studied the attack surfaces in the automotive cybersecurity domain. It also illustrated the attack methods and capabilities of the damages. Online survey has been deployed as data collection tool to learn about the consumers’ usage of such vulnerable automotive services. The second part of the research portrayed the consumers’ privacy in automotive world. It has been found that almost hundred percent of modern vehicles has the capabilities to send vehicle diagnostic data as well as user generated data to their manufacturers, and almost thirty five percent automotive companies are collecting them already. Internet privacy has been studies before in many related domain but no privacy scale were matched for automotive consumers. It created the research gap and motivation for this thesis. A study has been performed to use well established consumers privacy scale – IUIPC to match with the automotive consumers’ privacy situation. Hypotheses were developed based on the IUIPC model for internet consumers’ privacy and they were studied by the finding from the data collection methods. Based on the key findings of the research, all the hypotheses were accepted and hence it is found that automotive consumers’ privacy did follow the IUIPC model under certain conditions. It is also found that a majority of automotive consumers use the services and devices that are vulnerable and prone to cyber-attacks. It is also established that there is a market for automotive cybersecurity services and consumers are willing to pay certain fees to avail that.

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Microbial symbionts can modulate host interactions with biotic and abiotic factors. Such interactions may affect the evolutionary trajectories of both host and symbiont. Wolbachia protects Drosophila melanogaster against several viral infections and the strength of the protection varies between variants of this endosymbiont. Since Wolbachia is maternally transmitted, its fitness depends on the fitness of its host. Therefore, Wolbachia populations may be under selection when Drosophila is subjected to viral infection. Here we show that in D. melanogaster populations selected for increased survival upon infection with Drosophila C virus there is a strong selection coefficient for specific Wolbachia variants, leading to their fixation. Flies carrying these selected Wolbachia variants have higher survival and fertility upon viral infection when compared to flies with the other variants. These findings demonstrate how the interaction of a host with pathogens shapes the genetic composition of symbiont populations. Furthermore, host adaptation can result from the evolution of its symbionts, with host and symbiont functioning as a single evolutionary unit.