974 resultados para Tests de non corrélation


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1. Essential hypertension occurs in people with an underlying genetic predisposition who subject themselves to adverse environmental influences. The number of genes involved is unknown, as is the extent to which each contributes to final blood pressure and the severity of the disease. 2. In the past, studies of potential candidate genes have been performed by association (case-control) analysis of unrelated individuals or linkage (pedigree or sibpair) analysis of families. These studies have resulted in several positive findings but, as one may expect, also an enormous number of negative results. 3. In order to uncover the major genetic loci for essential hypertension, it is proposed that scanning the genome systematically in 100- 200 affected sibships should prove successful. 4. This involves genotyping sets of hypertensive sibships to determine their complement of several hundred microsatellite polymorphisms. Those that are highly informative, by having a high heterozygosity, are most suitable. Also, the markers need to be spaced sufficiently evenly across the genome so as to ensure adequate coverage. 5. Tests are performed to determine increased segregation of alleles of each marker with hypertension. The analytical tools involve specialized statistical programs that can detect such differences. Non- parametric multipoint analysis is an appropriate approach. 6. In this way, loci for essential hypertension are beginning to emerge.

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A new bioluminescent creatine kinase (CK) assay using purified luciferase was used to analyse CK activity in serum samples dried on filter paper. Enzyme activity was preserved for over 1 wk on paper stored at room temperature. At 60°C, CK activity in liquid serum samples was rapidly inactivated, but the activity of enzyme stored on paper was preserved for at least 2 days.

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Results of 3 tests, intravenous edrophonium chloride, EMG, and acetylcholine receptor antibody testing, were compared in patients with generalised and ocular myasthenia gravis. None of the 3 tests was positive in any patient with a diagnosis other than myasthenia. However, equivocal results were obtained with edrophonium and EMG testing in some patients with myasthenia gravis and in patients with other diseases. It is concluded from this survey that antibody and edrophonium testing were equally efficient in detecting generalised myasthenia gravis. Edrophonium testing was superior in ocular myasthenia gravis. Although the yields from each test varied, all 3 tests were needed for the evaluation of some myasthenia gravis patients as each test may provide additional information.

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A recent cross-sectional study has demonstrated a significant association of the R1 RsaI restriction fragment length polymorphism of the insulin receptor gene (INSR) with human essential hypertension. In the present study, an alternative approach, involving linkage analysis, was carried out using 8 hypertensive families with 5 or more affected members. Five of the families were found to be informative and in one of these pedigrees a conclusion of non-linkage of INSR and hypertension could be made on the basis of an obligate recombinant in one generation which yielded a Lod score of - ∞ at a recombination fraction (θ) of zero. In another family, the largest studied, a positive Lod score was obtained at θ = 0, but this was below the level required for a conclusion of linkage. Lod score at θ = 0 for a marker at the insulin locus in this family was negative. The present study has thus demonstrated one pedigree in which hypertension is not linked to the insulin receptor locus.

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Crashes that occur on motorways contribute to a significant proportion (40-50%) of non-recurrent motorway congestions. Hence, reducing the frequency of crashes assists in addressing congestion issues (Meyer, 2008). Crash likelihood estimation studies commonly focus on traffic conditions in a short time window around the time of a crash while longer-term pre-crash traffic flow trends are neglected. In this paper we will show, through data mining techniques that a relationship between pre-crash traffic flow patterns and crash occurrence on motorways exists. We will compare them with normal traffic trends and show this knowledge has the potential to improve the accuracy of existing models and opens the path for new development approaches. The data for the analysis was extracted from records collected between 2007 and 2009 on the Shibuya and Shinjuku lines of the Tokyo Metropolitan Expressway in Japan. The dataset includes a total of 824 rear-end and sideswipe crashes that have been matched with crashes corresponding to traffic flow data using an incident detection algorithm. Traffic trends (traffic speed time series) revealed that crashes can be clustered with regards to the dominant traffic patterns prior to the crash. Using the K-Means clustering method with Euclidean distance function allowed the crashes to be clustered. Then, normal situation data was extracted based on the time distribution of crashes and were clustered to compare with the “high risk” clusters. Five major trends have been found in the clustering results for both high risk and normal conditions. The study discovered traffic regimes had differences in the speed trends. Based on these findings, crash likelihood estimation models can be fine-tuned based on the monitored traffic conditions with a sliding window of 30 minutes to increase accuracy of the results and minimize false alarms.

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Numerically investigation of free convection heat transfer in a differentially heated trapezoidal cavity filled with non-Newtonian Power-law fluid has been performed in this study. The left inclined surface is uniformly heated whereas the right inclined surface is maintained as uniformly cooled. The top and bottom surfaces are kept adiabatic with initially quiescent fluid inside the enclosure. Finite volume based commercial software FLUENT 14.5 is used to solve the governing equations. Dependency of various flow parameters of fluid flow and heat transfer is analyzed including Rayleigh number, Ra ranging from 10^5 to 10^7, Prandtl number, Pr of 100 to 10,000 and power index, n of 0.6 to 1.4. Outcomes have been reported in terms of isotherms, streamline, and local Nusselt number for various Ra, Pr, n and inclined angles. Grid sensitivity analysis is performed and numerically obtained results have been compared with those results available in the literature and found good agreement.

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This paper aims to address the knowledge gap in regards to the potential intermediary role tertiary institutions can play in developing generic design thinking/design led innovation capabilities in non-designers. Specifically, it investigates the value derived from the contribution of postgraduate design students as facilitators/educators for undergraduate non-design student cohorts. It examines a design immersion workshop designed to encourage the use of design thinking capabilities for project brief development for undergraduate multi-disciplinary student teams involved in a community service learning project for a social enterprise. The workshop was facilitated by design led innovation masters students embedded in industry organisations to research the integration of design led innovation capabilities in business. Data was collected from participating non-design students and postgraduate facilitators’ in the form of reflective journals and semi-structured interviews. The thematic analysis provided insight into the value of design thinking/design led innovation immersion programs for both the postgraduate facilitators and the undergraduate non-design students. The research results will inform a tentative foundation prototype framework to allow for ongoing program developments and research in design thinking/design led innovation integration in higher education, facilitating the development of generic capabilities required to empower future generations for business innovation and active citizenship in the 21st century knowledge economy.

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Highly sensitive infrared cameras can produce high-resolution diagnostic images of the temperature and vascular changes of breasts. Wavelet transform based features are suitable in extracting the texture difference information of these images due to their scale-space decomposition. The objective of this study is to investigate the potential of extracted features in differentiating between breast lesions by comparing the two corresponding pectoral regions of two breast thermograms. The pectoral regions of breastsare important because near 50% of all breast cancer is located in this region. In this study, the pectoral region of the left breast is selected. Then the corresponding pectoral region of the right breast is identified. Texture features based on the first and the second sets of statistics are extracted from wavelet decomposed images of the pectoral regions of two breast thermograms. Principal component analysis is used to reduce dimension and an Adaboost classifier to evaluate classification performance. A number of different wavelet features are compared and it is shown that complex non-separable 2D discrete wavelet transform features perform better than their real separable counterparts.

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This study was undertaken to examine the influence that a set of Professional Development (PD) initiatives had on faculty use of Moodle, a well known Course Management System. The context of the study was a private language university just outside Tokyo, Japan. Specifically, it aimed to identify the way in which the PD initiatives adhered to professional development best practice criteria; how faculty members perceived the PD initiatives; what impact the PD initiatives had on faculty use of Moodle; and other variables that may have influenced faculty in their use of Moodle. The study utilised a mixed methods approach. Participants in the study were 42 teachers who worked at the university in the academic year 2008/9. The online survey consisted of 115 items, factored into 10 constructs. Data was collected through an online survey, semi-structured face-to-face interviews, post-workshop surveys, and a collection of textual artefacts. The quantitative data were analysed in SPSS, using descriptive statistics, Spearman's Rank Order correlation tests and a Kruskal-Wallis means test. The qualitative data was used to develop and expand findings and ideas. The results indicated that the PD initiatives adhered closely to criteria posited in technology-related professional development best practice criteria. Further, results from the online survey, post workshop surveys, and follow up face-to-face interviews indicated that while the PD initiatives that were implemented were positively perceived by faculty, they did not have the anticipated impact on Moodle use among faculty. Further results indicated that other variables, such as perceptions of Moodle, and institutional issues, had a considerable influence on Moodle use. The findings of the study further strengthened the idea that the five variables Everett Rogers lists in his Diffusion of Innovations model, including perceived attributes of an innovation; type of innovation decision; communication channels; nature of the social system; extent of change agents' promotion efforts, most influence the adoption of an innovation. However, the results also indicated that some of the variables in Rogers' DOI seem to have more of an influence than others, particularly the perceived attributes of an innovation variable. In addition, the findings of the study could serve to inform universities that have Course Management Systems (CMS), such as Moodle, about how to utilise them most efficiently and effectively. The findings could also help to inform universities about how to help faculty members acquire the skills necessary to incorporate CMSs into curricula and teaching practice. A limitation of this study was the use of a non-randomised sample, which could appear to have limited the generalisations of the findings to this particular Japanese context.

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Most large cities around the world are undergoing rapid transport sector development to cater for increased urbanization. Subsequently the issues of mobility, access equity, congestion, operational safety and above all environmental sustainability are becoming increasingly crucial in transport planning and policy making. The popular response in addressing these issues has been demand management, through improvement of motorised public transport (MPT) modes (bus, train, tram) and non-motorized transport (NMT) modes (walk, bicycle); improved fuel technology. Relatively little attention has however been given to another readily available and highly sustainable component of the urban transport system, non-motorized public transport (NMPT) such as the pedicab that operates on a commercial basis and serves as an NMT taxi; and has long standing history in many Asian cities; relatively stable in existence in Latin America; and reemerging and expanding in Europe, North America and Australia. Consensus at policy level on the apparent benefits, costs and management approach for NMPT integration has often been a major transport planning problem. Within this context, this research attempts to provide a more complete analysis of the current existence rationale and possible future, or otherwise, of NMPT as a regular public transport system. The analytical process is divided into three major stages. Stage 1 reviews the status and role condition of NMPT as regular public transport on a global scale- in developing cities and developed cities. The review establishes the strong ongoing and future potential role of NMPT in major developing cities. Stage 2 narrows down the status review to a case study city of a developing country in order to facilitate deeper role review and status analysis of the mode. Dhaka, capital city of Bangladesh, has been chosen due to its magnitude of NMPT presence. The review and analysis reveals the multisectoral and dominant role of NMPT in catering for the travel need of Dhaka transport users. The review also indicates ad-hoc, disintegrated policy planning in management of NMPT and the need for a planning framework to facilitate balanced integration between NMPT and MT in future. Stage 3 develops an integrated, multimodal planning framework (IMPF), based on a four-step planning process. This includes defining the purpose and scope of the planning exercise, determining current deficiencies and preferred characteristics for the proposed IMPF, selection of suitable techniques to address the deficiencies and needs of the transport network while laying out the IMPF and finally, development of a delivery plan for the IMPF based on a selected layout technique and integration approach. The output of the exercise is a planning instrument (decision tool) that can be used to assign a road hierarchy in order to allocate appropriate traffic to appropriate network type, particularly to facilitate the operational balance between MT and NMT. The instrument is based on a partial restriction approach of motorised transport (MT) and NMT, structured on the notion of functional hierarchy approach, and distributes/prioritises MT and NMT such that functional needs of the network category is best complemented. The planning instrument based on these processes and principles offers a six-level road hierarchy with a different composition of network-governing attributes and modal priority, for the current Dhaka transport network, in order to facilitate efficient integration of NMT with MT. A case study application of the instrument on a small transport network of Dhaka also demonstrates the utility, flexibility and adoptability of the instrument in logically allocating corridors with particular positions in the road hierarchy paradigm. Although the tool is useful in enabling balanced distribution of NMPT with MT at different network levels, further investigation is required with reference to detailed modal variations, scales and locations of a network to further generalise the framework application.

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Collagen crosslinking (CXL) has shown promising results in the prevention of the progression of keratoconus and corneal ectasia. However, techniques for in vivo and in situ assessment of the treatment are limited. In this study, ex vivo porcine eyes were treated with a chemical CXL agent (glutaraldehyde), during which polarization sensitive optical coherence tomography (PS-OCT) recordings were acquired simultaneously to assess the sensitivity of the technique to assess changes in the cornea. The results obtained in this study suggest that PS-OCT may be a suitable technique to measure CXL changes in situ and to assess the local changes in the treated region of the cornea.

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Claims that violence is gender-neutral are increasingly becoming “common sense” in Canada. Antifeminist groups assert that the high rates of woman abuse uncovered by major Canadian national surveys conducted in the early 1990s are greatly exaggerated and that women are as violent as men. The production of degendered rhetoric about “intimate partner violence” contributes to claims that women’s and men’s violence is symmetrical and mutual. This article critically evaluates common claims about Canadian women’s use of nonlethal force in heterosexual intimate relationships in the context of the political struggle over the hegemonic frame for violence and abuse. The extant Canadian research documenting significant sex differences in violence and abuse against adult intimate partners is reviewed.

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Boron nitride nanotubes were functionalized by microperoxidase-11 in aqueous media, showing improved catalytic performance due to a strong electron coupling 10 between the active centre of microperoxidase-11 and boron nitride nanotubes. One main application challenge of enzymes as biocatalysts is molecular aggregation in the aqueous solution. This issue is addressed by immobilization of enzymes on solid supports which 15 can enhance enzyme stability and facilitate separation, and recovery for reuse while maintaining catalytic activity and selectivity. The protein-nanoparticle interactions play a key role in bio-nanotechnology and emerge with the development of nanoparticle-protein “corona”. Bio-molecular coronas provide a 20 unique biological identity of nanosized materials.1, 2 As a structural analogue to carbon nanotubes (CNTs), Boron nitride nanotubes have boron and nitrogen atoms distributed equally in hexagonal rings and exhibit excellent mechanical strength, unique physical properties, and chemical stability at high-temperatures. 25 The chemical inertness of BN materials suits to work in hazardous environments, making them an optimal candidate in practical applications in biological and medical field.3, 4

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Non-periodic structural variation has been found in the high Tc cuprates, YBa2Cu3O7-x and Hg0.67Pb0.33Ba2Ca2Cu 3O8+δ, by image analysis of high resolution transmission electron microscope (HRTEM) images. We use two methods for analysis of the HRTEM images. The first method is a means for measuring the bending of lattice fringes at twin planes. The second method is a low-pass filter technique which enhances information contained by diffuse-scattered electrons and reveals what appears to be an interference effect between domains of differing lattice parameter in the top and bottom of the thin foil. We believe that these methods of image analysis could be usefully applied to the many thousands of HRTEM images that have been collected by other workers in the high temperature superconductor field. This work provides direct structural evidence for phase separation in high Tc cuprates, and gives support to recent stripes models that have been proposed to explain various angle resolved photoelectron spectroscopy and nuclear magnetic resonance data. We believe that the structural variation is a response to an opening of an electronic solubility gap where holes are not uniformly distributed in the material but are confined to metallic stripes. Optimum doping may occur as a consequence of the diffuse boundaries between stripes which arise from spinodal decomposition. Theoretical ideas about the high Tc cuprates which treat the cuprates as homogeneous may need to be modified in order to take account of this type of structural variation.