883 resultados para Nonlinear correlation coefficients


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Purpose: This study was conducted to examine the test-retest reliability of a measure of prediagnosis physical activity participation administered to colorecial cancer survivors recruited from a population-based state cancer registry. Methods: A total of 112 participants completed two telephone interviews. I month apart, reporting usual weekly physical activity in the year before their cancer diagnosis. Intraclass correlation coefficients (ICC) and standard en-or of measurement (SEM) were used to describe the test-retest reliability of the measure across the sample: the Bland-Altman approach was used to describe reliability at the individual level. The test-retest reliability for categorized total physical activity (active, insufficiently active, sedentary) was assessed using the kappa statistic. Results: When the complete sample was considered, the ICC ranged from 0.40 (95% Cl: 0.24, 0.55) for vigorous gardening to 0.77 (95% Cl: 0.68, 0.84) for moderate physical activity. The SEM, however, were large. indicating high measurement error. The Bland-Altman plots indicated that the reproducibility of data decreases as the aniount of physical activity reported each week increases The kappa coefficient for the categorized data was 0.62 (95% Cl: 0.48, 0.76). Conclusion: Overall. the results indicated low levels of repeatability for this measure of historical physical activity. Categorizing participants as active, insufficiently active, or sedentary provides a higher level of test-retest reliability.

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Objective: To establish concurrent validity, interrater and test-retest reliability of the Modified Elderly Mobility Scale (MEMS). Methods: Ninety elderly patients were scored on the MEMS. To establish concurrent validity, 75 patients MEMS scores were compared to Functional Independence Measure (FIM) scores using Spearman's correlation. Videotaped patient performances were used to establish interrater and test-retest reliability using percentage absolute agreement and intraclass correlation coefficients (ICCs). Results: The total MEMS score demonstrated a significant association with the motor (r = 0.725) and total FIM scores (r = 0.718). Absolute agreement for interrater reliability was greater than 93% for all test items, with 97 and 98% for the two new measures, respectively. Test-retest reliability demonstrated similar high levels of absolute agreement and had ICCs ranging from 0.870 to 1.0. Conclusions: The MEMS is a quick, valid and reliable test of motor function of elderly patients with a spread of functional levels.

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The Rapid Screen of Concussion (RSC) is a brief psychometric test battery, designed to provide a functional criterion to aid clinical diagnosis of mild traumatic brain injury (mTBI). The present research aimed to examine the utility of this instrument for assessing recovery after mTBI. Three studies were conducted. In Study 1, Discriminant Function Analysis was performed to determine how well the RSC differentiated uninjured controls (N¼16), from mTBI patients (N¼22) and moderate to severe TBI patients (N¼14), several months post-injury. As predicted, moderate to severe TBI patients achieved lower scores than the mTBI and control groups. The RSC also successfully differentiated between each of the diagnostic groups, yielding an overall correct classification rate of 75%. Study 2 examined the predictive utility of the RSC in the mTBI sample (N¼22). Acute injury performance on the RSC was correlated with post-injury scores at an average of 5.5 months post-injury. Statistically significant partial correlation coefficients (r¼0.53r¼0.80) were found for each of the subtests, showing that low acute RSC scores were predictive of poor recovery scores on the RSC after mTBI. In the third study, Reliable Change Indices were calculated on the RSC subtests to examine individual patterns of recovery from mTBI. While 17 of the 23 participants made a significant improvement on their acute injury DSST scores (74%), only 13 of 25 made a significant improvement on the Rapid Sentence Judgement Test (52%), highlighting differential recovery of function, and challenging the notion of full recovery from mTBI within 3 months. These overall results offer support for the construct and predictive validity of the RSC and demonstrate that inexpensive tests of brain function may be useful for managing mTBI acutely for prognosis.

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A field study in three vineyards in southern Queensland (Australia) was carried out to develop predictive models for individual leaf area and shoot leaf area of two cultivars (Cabernet Sauvignon and Shiraz) of grapevines (Vitis Vinifera L.). Digital image analysis was used to measure leaf vein length and leaf area. Stepwise regressions of untransformed and transformed models consisting of up to six predictor variables for leaf area and three predictor variables for shoot leaf area were carried out to obtain the most efficient models. High correlation coefficients were found for log10 transformed individual leaf and shoot leaf area models. The significance of predictor variables in the models varied across vineyards and cultivars, demonstrating the discontinuous and heterogeneous nature of vineyards. The application of this work in a grapevine modeling environment and in a dynamic vineyard management context are discussed. Sample sizes for quantification of individual leaf areas and areas of leaves on shoots are proposed based on target margins of errors of sampled data.

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Esta dissertação tem por objetivo geral analisar as relações entre percepção de sucesso na carreira, bem-estar no trabalho e desempenho de professores de ensino a distância (EaD). Para tanto, realizamos uma pesquisa por meio de um questionário de autopreenchimento para a coleta de dados com 128 professores da EaD de uma instituição superior particular situada no estado do Rio de Janeiro. Para a discussão e busca dos resultados das análises dos dados foi utilizado o software estatístico SPSS Statistical Package for the Social Science, versão 18.0 para Windows. Foram calculadas médias; desvios padrão; índices de correlação (r de Pearson); e diferenças entre médias (t de student). Os resultados indicam, por meio das respostas aos instrumentos aplicados, que os professores de EaD tiveram sucesso na carreira docente tão proporcional às demais variáveis e que é possível constatar que os professores de EaD pesquisados apresentam níveis elevados de bem-estar no trabalho em suas dimensões (satisfação no trabalho, envolvimento no trabalho e comprometimento organizacional afetivo) pois, estão satisfeitos em seus trabalhos e muito comprometidos afetivamente com a instituição de ensino e por fim, confirmam a tendência na ocorrência de níveis consideráveis de desempenho. Portanto, conclui-se que em relação à percepção de sucesso na carreira, ao bem estar no trabalho, e ao desempenho, os professores estudados estão satisfeitos com sua atuação profissional da educação a distância, sendo que as dimensões de bem-estar são as preferidas dos pesquisadores, pois apresentam variáveis positivas e significativas sobre os demais constructos desta pesquisa.

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O conflito trabalho-família é um fenômeno freqüente nas sociedades atuais em que homens e mulheres dividem responsabilidades familiares e profissionais. A sua direção pode ser unidirecional ou bidirecional, ou seja, da família para o trabalho, do trabalho para a família ou simultaneamente de uma esfera para outra, afetando sensivelmente as relações familiares e as relações nas organizações, sendo possível afetar diretamente o bem-estar dos indivíduos. Este é um estudo de natureza quantitativa e com desenho transversal. O critério para a escolha de participantes foi o de conveniência. O objetivo geral desta pesquisa foi analisar as relações entre conflito trabalho-família (CTF), bem-estar subjetivo (BES) e bem-estar no trabalho (BET). O estudo contou com a participação de 174 trabalhadores em uma amostra diversificada de profissionais do segmento privado, público e de ONG, sendo 52,9% do sexo feminino, com idade média de 38,29 anos (DP=11,22). Para a obtenção dos dados optou-se por um questionário abrangendo as três variáveis do estudo contendo duas escalas para aferir as dimensões de BES, uma escala para aferir BET e uma escala para aferir CTF/CFT. Para a análise dos dados foi usado o SPSS, versão 20. Foram calculadas frequências, percentuais, médias, desvios-padrão, e índices de correlação, bem como índices de precisão das medidas usadas (Alpha de Cronbach). Os resultados apontaram para uma maior interferência do trabalho na família do que da família no trabalho. Essa interferência foi significativa tanto para o bem-estar no trabalho, quanto para o bem-estar subjetivo, alterando o envolvimento com o trabalho e gerando sentimentos de infelicidade, desânimo e angústia em relação as suas realizações pessoais, e ao futuro. Quanto maior o conflito trabalho-família, menor é o bem-estar no trabalho e menor é o bem-estar subjetivo desses participantes.

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Desde tempos remotos é notória a busca da humanidade para entender e conquistar a felicidade, qualidade de vida, bem-estar e saúde na sua plenitude bio-psico-social. Assim, o objetivo geral deste estudo foi analisar as relações entre percepções de suporte (social, social no trabalho e organizacional) e bem-estar no trabalho (satisfação no trabalho, envolvimento com o trabalho e comprometimento organizacional afetivo) em trabalhadores com deficiência, pois são poucas as pesquisas sobre pessoas com deficiência (PCD). O propósito em abordar o trabalho é por ser um importante elemento de integração social e por constituir um símbolo de reconhecimento social, valorizando a capacidade de estreitar contatos e de estabelecer relações sociais. Deste estudo, participaram 44 trabalhadores com algum tipo de deficiência que atuam em cargos operacionais, técnicos e administrativos. Todos foram escolhidos por conveniência, sendo 24 (54,5%) do sexo masculino e 20 (45,5%) do sexo feminino, com idade entre 18 e 65 anos. Foi possível classificar as deficiências dos participantes em quatro categorias: deficiência nos membros superiores: 9 (20,5%) trabalhadores; deficiência nos membros inferiores: 11 (25%) trabalhadores; deficiência auditiva: 21 (47,7%) trabalhadores; deficiência visual: 3 (6,8%) trabalhadores. Para a coleta de dados foi utilizado questionário de auto-preenchimento, composto de seis escalas que avaliam satisfação no trabalho, envolvimento com o trabalho e comprometimento organizacional, além de suporte social, suportes social no trabalho e organizacional. Foram realizadas análises estatísticas descritivas, testadas diferenças entre médias, bem como calculados coeficientes de correlação entre variáveis. Os resultados apontam que em termos de satisfação no trabalho, não revelam discrepâncias entre estudos realizados com trabalhadores sem deficiências (considerados normais ). Também foi possível observar que as PCD declaram ter orgulho da empresa em que trabalham, além de estarem contentes, entusiasmadas, interessadas e animadas com a organização empregadora. O estudo revelou que as PCD obtêm de sua rede social, ajuda emocional que lhes proporciona sentimento de apoio frente às dificuldades ou carências afetivas, pois provavelmente entendam que podem contar com essa rede para comemorar realizações e sucessos, da mesma forma que receber carinho e consolo quando se frustram ou passam por algum momento triste. É possível afirmar que as PCD percebem que essa mesma rede seria capaz de lhes prover algum apoio prático, como receber informações acerca de sua saúde, talvez reabilitação, também informações para atualização profissional ou até acompanhamento do seu desenvolvimento, inclusive busca de novas oportunidades e desafios para crescimento pessoal e profissional. Os resultados desta pesquisa indicam que as PCD tendem a manter uma forte convicção de que a empresa em que trabalham preocupa-se com seu bem-estar e está disposta a oferecer ajuda diante uma necessidade. Demais resultados sinalizam que as PCD tendem a aumentar o seu vínculo com o trabalho vivenciando mais satisfação na medida em que também aumentam os suportes ofertados pela organização, pela rede social no contexto do trabalho e fora dele. A análise de todo o conteúdo confeccionado é a grande contribuição deste estudo, por ser considerado pioneiro nesta discussão, mas futuros estudos podem vir a confirmar tais resultados e corroborar com mais informações.(AU)

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PURPOSE: To provide a consistent standard for the evaluation of different types of presbyopic correction. SETTING: Eye Clinic, School of Life and Health Sciences, Aston University, Birmingham, United Kingdom. METHODS: Presbyopic corrections examined were accommodating intraocular lenses (IOLs), simultaneous multifocal and monovision contact lenses, and varifocal spectacles. Binocular near visual acuity measured with different optotypes (uppercase letters, lowercase letters, and words) and reading metrics assessed with the Minnesota Near Reading chart (reading acuity, critical print size [CPS], CPS reading speed) were intercorrelated (Pearson product moment correlations) and assessed for concordance (intraclass correlation coefficients [ICC]) and agreement (Bland-Altman analysis) for indication of clinical usefulness. RESULTS: Nineteen accommodating IOL cases, 40 simultaneous contact lens cases, and 38 varifocal spectacle cases were evaluated. Other than CPS reading speed, all near visual acuity and reading metrics correlated well with each other (r>0.70, P<.001). Near visual acuity measured with uppercase letters was highly concordant (ICC, 0.78) and in close agreement with lowercase letters (+/- 0.17 logMAR). Near word acuity agreed well with reading acuity (+/- 0.16 logMAR), which in turn agreed well with near visual acuity measured with uppercase letters 0.16 logMAR). Concordance (ICC, 0.18 to 0.46) and agreement (+/- 0.24 to 0.30 logMAR) of CPS with the other near metrics was moderate. CONCLUSION: Measurement of near visual ability in presbyopia should be standardized to include assessment of near visual acuity with logMAR uppercase-letter optotypes, smallest logMAR print size that maintains maximum reading speed (CPS), and reading speed. J Cataract Refract Surg 2009; 35:1401-1409 (C) 2009 ASCRS and ESCRS

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This thesis considers two basic aspects of impact damage in composite materials, namely damage severity discrimination and impact damage location by using Acoustic Emissions (AE) and Artificial Neural Networks (ANNs). The experimental work embodies a study of such factors as the application of AE as Non-destructive Damage Testing (NDT), and the evaluation of ANNs modelling. ANNs, however, played an important role in modelling implementation. In the first aspect of the study, different impact energies were used to produce different level of damage in two composite materials (T300/914 and T800/5245). The impacts were detected by their acoustic emissions (AE). The AE waveform signals were analysed and modelled using a Back Propagation (BP) neural network model. The Mean Square Error (MSE) from the output was then used as a damage indicator in the damage severity discrimination study. To evaluate the ANN model, a comparison was made of the correlation coefficients of different parameters, such as MSE, AE energy, AE counts, etc. MSE produced an outstanding result based on the best performance of correlation. In the second aspect, a new artificial neural network model was developed to provide impact damage location on a quasi-isotropic composite panel. It was successfully trained to locate impact sites by correlating the relationship between arriving time differences of AE signals at transducers located on the panel and the impact site coordinates. The performance of the ANN model, which was evaluated by calculating the distance deviation between model output and real location coordinates, supports the application of ANN as an impact damage location identifier. In the study, the accuracy of location prediction decreased when approaching the central area of the panel. Further investigation indicated that this is due to the small arrival time differences, which defect the performance of ANN prediction. This research suggested increasing the number of processing neurons in the ANNs as a practical solution.

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This exploratory study is concerned with the integrated appraisal of multi-storey dwelling blocks which incorporate large concrete panel systems (LPS). The first step was to look at U.K. multi-storey dwelling stock in general, and under the management of Birmingham City Council in particular. The information has been taken from the databases of three departments in the City of Birmingham, and rearranged in a new database using a suite of PC software called `PROXIMA' for clarity and analysis. One hundred of their stock were built large concrete panel system. Thirteen LPS blocks were chosen for the purpose of this study as case-studies depending mainly on the height and age factors of the block. A new integrated appraisal technique has been created for the LPS dwelling blocks, which takes into account the most physical and social factors affecting the condition and acceptability of these blocks. This appraisal technique is built up in a hierarchical form moving from the general approach to particular elements (a tree model). It comprises two main approaches; physical and social. In the physical approach, the building is viewed as a series of manageable elements and sub-elements to cover every single physical or environmental factor of the block, in which the condition of the block is analysed. A quality score system has been developed which depends mainly on the qualitative and quantitative conditions of each category in the appraisal tree model, and leads to physical ranking order of the study blocks. In the social appraisal approach, the residents' satisfaction and attitude toward their multi-storey dwelling block was analysed in relation to: a. biographical and housing related characteristics; and b. social, physical and environmental factors associated with this sort of dwelling, block and estate in general.The random sample consisted of 268 residents living in the 13 case study blocks. Data collected was analysed using frequency counts, percentages, means, standard deviations, Kendall's tue, r-correlation coefficients, t-test, analysis of variance (ANOVA) and multiple regression analysis. The analysis showed a marginally positive satisfaction and attitude towards living in the block. The five most significant factors associated with the residents' satisfaction and attitude in descending order were: the estate, in general; the service categories in the block, including heating system and lift services; vandalism; the neighbours; and the security system of the block. An important attribute of this method, is that it is relatively inexpensive to implement, especially when compared to alternatives adopted by some local authorities and the BRE. It is designed to save time, money and effort, to aid decision making, and to provide ranked priority to the multi-storey dwelling stock, in addition to many other advantages. A series of solution options to the problems of the block was sought for selection and testing before implementation. The traditional solutions have usually resulted in either demolition or costly physical maintenance and social improvement of the blocks. However, a new solution has now emerged, which is particularly suited to structurally sound units. The solution of `re-cycling' might incorporate the reuse of an entire block or part of it, by removing panels, slabs and so forth from the upper floors in order to reconstruct them as low-rise accommodations.

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The research presented in this thesis investigates the nature of the relationship between the development of the Knowledge-Based Economy (KBE) and Structural Funds (SF) in European regions. A particular focus is placed on the West Midlands (UK) and Silesia (Poland). The time-frame taken into account in this research is the years 1999 to 2009. This is methodologically addressed by firstly establishing a new way of calculating the General Index of the KBE for all of the EU regions; secondly, applying a number of statistical methods to measure the influence of the Funds on the changes in the regional KBE over time; and finally, by conducting a series of semi-structured stakeholder interviews in the two key case study regions: the West Midlands and Silesia. The three main findings of the thesis are: first, over the examined time-frame, the values of the KBE General Index increased in over 66% of the EU regions; furthermore, the number of the “new” EU regions in which the KBE increased over time is far higher than in the “old” EU. Second, any impact of Structural Funds on the regional KBE occurs only in the minority of the European regions and any form of functional dependency between the two can be observed only in 30% of the regions. Third, although the pattern of development of the regional KBE and the correlation coefficients differ in the cases of Silesia and the West Midlands, the analysis of variance carried out yields identical results for both regions. Furthermore, the qualitative analysis’ results show similarities in the approach towards the Structural Funds in the two key case-study regions.

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Evidence of the relationship between altered cognitive function and depleted Fe status is accumulating in women of reproductive age but the degree of Fe deficiency associated with negative neuropsychological outcomes needs to be delineated. Data are limited regarding this relationship in university women in whom optimal cognitive function is critical to academic success. The aim of the present study was to examine the relationship between body Fe, in the absence of Fe-deficiency anaemia, and neuropsychological function in young college women. Healthy, non-Anaemic undergraduate women (n 42) provided a blood sample and completed a standardised cognitive test battery consisting of one manual (Tower of London (TOL), a measure of central executive function) and five computerised (Bakan vigilance task, mental rotation, simple reaction time, immediate word recall and two-finger tapping) tasks. Women's body Fe ranged from - 4·2 to 8·1 mg/kg. General linear model ANOVA revealed a significant effect of body Fe on TOL planning time (P= 0.002). Spearman's correlation coefficients showed a significant inverse relationship between body Fe and TOL planning time for move categories 4 (r - 0.39, P= 0.01) and 5 (r - 0.47, P= 0.002). Performance on the computerised cognitive tasks was not affected by body Fe level. These findings suggest that Fe status in the absence of anaemia is positively associated with central executive function in otherwise healthy college women. Copyright © The Authors 2012.

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Statistical mechanics of two coupled vector fields is studied in the tight-binding model that describes propagation of polarized light in discrete waveguides in the presence of the four-wave mixing. The energy and power conservation laws enable the formulation of the equilibrium properties of the polarization state in terms of the Gibbs measure with positive temperature. The transition line T=∞ is established beyond which the discrete vector solitons are created. Also in the limit of the large nonlinearity an analytical expression for the distribution of Stokes parameters is obtained, which is found to be dependent only on the statistical properties of the initial polarization state and not on the strength of nonlinearity. The evolution of the system to the final equilibrium state is shown to pass through the intermediate stage when the energy exchange between the waveguides is still negligible. The distribution of the Stokes parameters in this regime has a complex multimodal structure strongly dependent on the nonlinear coupling coefficients and the initial conditions.

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During the 2004 growing season, five raspberry cultivars were evaluated in terms of their susceptibility to the raspberry cane midge (Resseliella theobaldi Barnes). The trial was carried out at Berkenye, Nógrád County, Hungary. The cultivars evaluated were ‘Rubaca’ from Germany, ‘Fertődi Zamatos’ from Hungary, ‘Tulameen’ from Canada, and ‘Autumn Bliss’ and ‘Golden Bliss’ from the United Kingdom. Every other week, twenty-five split primocanes of each cultivar were randomly collected for laboratory examination. Data recorded for each cultivar included the mean number of larvae, the mean split length, and the mean extent of bark peeling per primocane. Pearson’s linear correlation coefficients were calculated for the correlations between the annual mean number of larvae per primocane on the one hand, and the annual cumulative mean split length per primocane and annual mean extent of bark peeling per primocane on the other hand. There was a weak correlation between annual mean number of larvae and annual cumulative mean split length, and a stronger correlation between annual mean number of larvae and annual mean extent of bark peeling. Annual mean number of larvae per primocane and annual mean extent of bark peeling per primocane were both highest in ‘Rubaca’, which means that the number of larvae per cane largely depends on the extent of stem peeling, although longitudinal splitting may also play a role. Therefore, cultivars with hardly any bark peeling and few and small longitudinal splits can be presumed to be less susceptible to infestation by the raspberry cane midge. Using these criteria, the least susceptible of the five cultivars evaluated would be ‘Tulameen’ and ‘Fertődi Zamatos’. Further research is needed to confirm this conclusion and to gather data on other factors which affect cultivar choice for new plantations, including winter hardiness, and susceptibility to cane diseases.

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There is currently a crisis in science education in the United States. This statement is based on the National Science Foundation's report stating that the nation's students, on average, still rank near the bottom in science and math achievement internationally. ^ This crisis is the background of the problem for this study. This investigation studied learner variables that were thought to play a role in teaching chemistry at the secondary school level, and related them to achievement in the chemistry classroom. Among these, cognitive style (field dependence/independence), attitudes toward science, and self-concept had been given considerable attention by researchers in recent years. These variables were related to different competencies that could be used to measure the various types of achievement in the chemistry classroom at the secondary school level. These different competencies were called academic, laboratory, and problem solving achievement. Each of these chemistry achievement components may be related to a different set of learner variables, and the main purpose of this study was to investigate the nature of these relationships. ^ Three instruments to determine attitudes toward science, cognitive style, and self-concept were used for data collection. Teacher grades were used to determine chemistry achievement for each student. ^ Research questions were analyzed using Pearson Product Moment Correlation Coefficients and t-tests. Results indicated that field independence was significantly correlated with problem solving, academic, and laboratory achievement. Educational researchers should therefore investigate how to teach students to be more field independent so they can achieve at higher levels in chemistry. ^ It was also true that better attitudes toward the social benefits and problems that accompany scientific progress were significantly correlated with higher achievement on all three academic measures in chemistry. This suggests that educational researchers should investigate how students might be guided to manifest more favorable attitudes toward science so they will achieve at higher levels in chemistry. ^ An overall theme that emerged from this study was that findings refuted the idea that female students believed that science was for males only and was an inappropriate and unfeminine activity. This was true because when the means of males and females were compared on the three measures of chemistry achievement, there was no statistically significant difference between them on problem solving or academic achievement. However, females were significantly better in laboratory achievement. ^