963 resultados para Computer-assisted instruction.


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Em 2016 o inquérito ECOS foi implementado, através de entrevista telefónica assistida por computador, à semelhança de vagas anteriores, e ainda por via eletrónica. O questionário foi respondido por um elemento com 18 ou mais anos residente na unidade de alojamento, que prestou informação sobre a sua saúde e dos restantes elementos do agregado (por proxy). No total obtiveram-se 803 entrevistas concluídas e uma taxa de participação global de 79,9%. Considerando os contactos realizados via telefónica, a taxa de participação foi de 77,4% e de 26,5% por via web. Em ambas as vias, a maioria dos respondentes era do sexo feminino, encontrando-se a maior frequência de respondentes por telefone no grupo etário 60-69 e via web no grupo 40-49. As taxas de resposta obtidas em 2016 foram semelhantes às obtidas em outras vagas do ECOS por via telefónica (aproximadamente 80% vs 79 a 86%), e na via web foi superior às obtidas em estudos similares. O perfil dos respondentes em cada uma das vias foi consistente com o observado em estudos que utilizaram estas metodologias, nomeadamente, uma maior frequência de respondentes do sexo feminino e uma maior adesão à via web dos grupos etários mais novos.

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Introduction Prediction of soft tissue changes following orthognathic surgery has been frequently attempted in the past decades. It has gradually progressed from the classic “cut and paste” of photographs to the computer assisted 2D surgical prediction planning; and finally, comprehensive 3D surgical planning was introduced to help surgeons and patients to decide on the magnitude and direction of surgical movements as well as the type of surgery to be considered for the correction of facial dysmorphology. A wealth of experience was gained and numerous published literature is available which has augmented the knowledge of facial soft tissue behaviour and helped to improve the ability to closely simulate facial changes following orthognathic surgery. This was particularly noticed following the introduction of the three dimensional imaging into the medical research and clinical applications. Several approaches have been considered to mathematically predict soft tissue changes in three dimensions, following orthognathic surgery. The most common are the Finite element model and Mass tensor Model. These were developed into software packages which are currently used in clinical practice. In general, these methods produce an acceptable level of prediction accuracy of soft tissue changes following orthognathic surgery. Studies, however, have shown a limited prediction accuracy at specific regions of the face, in particular the areas around the lips. Aims The aim of this project is to conduct a comprehensive assessment of hard and soft tissue changes following orthognathic surgery and introduce a new method for prediction of facial soft tissue changes.   Methodology The study was carried out on the pre- and post-operative CBCT images of 100 patients who received their orthognathic surgery treatment at Glasgow dental hospital and school, Glasgow, UK. Three groups of patients were included in the analysis; patients who underwent Le Fort I maxillary advancement surgery; bilateral sagittal split mandibular advancement surgery or bimaxillary advancement surgery. A generic facial mesh was used to standardise the information obtained from individual patient’s facial image and Principal component analysis (PCA) was applied to interpolate the correlations between the skeletal surgical displacement and the resultant soft tissue changes. The identified relationship between hard tissue and soft tissue was then applied on a new set of preoperative 3D facial images and the predicted results were compared to the actual surgical changes measured from their post-operative 3D facial images. A set of validation studies was conducted. To include: • Comparison between voxel based registration and surface registration to analyse changes following orthognathic surgery. The results showed there was no statistically significant difference between the two methods. Voxel based registration, however, showed more reliability as it preserved the link between the soft tissue and skeletal structures of the face during the image registration process. Accordingly, voxel based registration was the method of choice for superimposition of the pre- and post-operative images. The result of this study was published in a refereed journal. • Direct DICOM slice landmarking; a novel technique to quantify the direction and magnitude of skeletal surgical movements. This method represents a new approach to quantify maxillary and mandibular surgical displacement in three dimensions. The technique includes measuring the distance of corresponding landmarks digitized directly on DICOM image slices in relation to three dimensional reference planes. The accuracy of the measurements was assessed against a set of “gold standard” measurements extracted from simulated model surgery. The results confirmed the accuracy of the method within 0.34mm. Therefore, the method was applied in this study. The results of this validation were published in a peer refereed journal. • The use of a generic mesh to assess soft tissue changes using stereophotogrammetry. The generic facial mesh played a major role in the soft tissue dense correspondence analysis. The conformed generic mesh represented the geometrical information of the individual’s facial mesh on which it was conformed (elastically deformed). Therefore, the accuracy of generic mesh conformation is essential to guarantee an accurate replica of the individual facial characteristics. The results showed an acceptable overall mean error of the conformation of generic mesh 1 mm. The results of this study were accepted for publication in peer refereed scientific journal. Skeletal tissue analysis was performed using the validated “Direct DICOM slices landmarking method” while soft tissue analysis was performed using Dense correspondence analysis. The analysis of soft tissue was novel and produced a comprehensive description of facial changes in response to orthognathic surgery. The results were accepted for publication in a refereed scientific Journal. The main soft tissue changes associated with Le Fort I were advancement at the midface region combined with widening of the paranasal, upper lip and nostrils. Minor changes were noticed at the tip of the nose and oral commissures. The main soft tissue changes associated with mandibular advancement surgery were advancement and downward displacement of the chin and lower lip regions, limited widening of the lower lip and slight reversion of the lower lip vermilion combined with minimal backward displacement of the upper lip were recorded. Minimal changes were observed on the oral commissures. The main soft tissue changes associated with bimaxillary advancement surgery were generalized advancement of the middle and lower thirds of the face combined with widening of the paranasal, upper lip and nostrils regions. In Le Fort I cases, the correlation between the changes of the facial soft tissue and the skeletal surgical movements was assessed using PCA. A statistical method known as ’Leave one out cross validation’ was applied on the 30 cases which had Le Fort I osteotomy surgical procedure to effectively utilize the data for the prediction algorithm. The prediction accuracy of soft tissue changes showed a mean error ranging between (0.0006mm±0.582) at the nose region to (-0.0316mm±2.1996) at the various facial regions.

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Lung cancer is the most frequently fatal cancer, with poor survival once the disease is advanced. Annual low-dose computed tomography has shown a survival benefit in screening individuals at high risk for lung cancer. Based on the available evidence, the European Society of Radiology and the European Respiratory Society recommend lung cancer screening in comprehensive, quality-assured, longitudinal programmes within a clinical trial or in routine clinical practice at certified multidisciplinary medical centres. Minimum requirements include: standardised operating procedures for low-dose image acquisition, computer-assisted nodule evaluation, and positive screening results and their management; inclusion/exclusion criteria; expectation management; and smoking cessation programmes. Further refinements are recommended to increase quality, outcome and cost-effectiveness of lung cancer screening: inclusion of risk models, reduction of effective radiation dose, computer-assisted volumetric measurements and assessment of comorbidities (chronic obstructive pulmonary disease and vascular calcification). All these requirements should be adjusted to the regional infrastructure and healthcare system, in order to exactly define eligibility using a risk model, nodule management and a quality assurance plan. The establishment of a central registry, including a biobank and an image bank, and preferably on a European level, is strongly encouraged. Key points: • Lung cancer screening using low dose computed tomography reduces mortality. • Leading US medical societies recommend large scale screening for high-risk individuals. • There are no lung cancer screening recommendations or reimbursed screening programmes in Europe as of yet. • The European Society of Radiology and the European Respiratory Society recommend lung cancer screening within a clinical trial or in routine clinical practice at certified multidisciplinary medical centres. • High risk, eligible individuals should be enrolled in comprehensive, quality-controlled longitudinal programmes.

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For a long time, electronic data analysis has been associated with quantitative methods. However, Computer Assisted Qualitative Data Analysis Software (CAQDAS) are increasingly being developed. Although the CAQDAS has been there for decades, very few qualitative health researchers report using it. This may be due to the difficulties that one has to go through to master the software and the misconceptions that are associated with using CAQDAS. While the issue of mastering CAQDAS has received ample attention, little has been done to address the misconceptions associated with CAQDAS. In this paper, the author reflects on his experience of interacting with one of the popular CAQDAS (NVivo) in order to provide evidence-based implications of using the software. The key message is that unlike statistical software, the main function of CAQDAS is not to analyse data but rather to aid the analysis process, which the researcher must always remain in control of. In other words, researchers must equally know that no software can analyse qualitative data. CAQDAS are basically data management packages, which support the researcher during analysis.

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Introducción: El objetivo de este trabajo es hacer una revisión y actualización de la literatura sobre la aportación de la planificación quirúrgica y de la navegación en el manejo de la enfermedad oncológica de cabeza y cuello, para valorar y determinar sus aplicaciones actuales. Material y métodos: Se realiza una búsqueda electrónica empleando los términos craniomaxillofacial tumors, head and neck cancer, navigation system, computer-assisted surgery y oral cancer. Resultados: El número de artículos encontrados en la revisión de la literatura ha sido de 16, publicados entre los años 1991 y 2014. Entre ellos no hay ninguna revisión sistemática, hay 5 artículos de revisión, 6 series de casos y 5 casos clínicos. Solo 10 artículos aportan información completa en relación con la enfermedad oncológica manejada con tecnología de navegación quirúrgica. Actualmente las aplicaciones de la navegación en oncología de cabeza y cuello pueden enumerarse en las siguientes áreas: biopsia guiada, resección y reconstrucción de tumores, monitorización del volumen del tumor, control de márgenes de resección quirúrgica basados en TC, RMN o PET y sistema de comunicación interdisciplinar. Conclusiones: Actualmente hay un número escaso de publicaciones sobre las aplicaciones de la navegación quirúrgica en el novedoso ámbito de la oncología de cabeza y cuello. A pesar de la ausencia de revisiones sistemáticas, parece tener un futuro prometedor por la valiosa aportación que hace para el manejo de tumores de cabeza y cuello, como proporcionar precisión anatómica, precisión diagnóstica y seguridad quirúrgica, siendo de gran utilidad en el tratamiento oncológico multidisciplinar.

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Inter-subject parcellation of functional Magnetic Resonance Imaging (fMRI) data based on a standard General Linear Model (GLM) and spectral clustering was recently proposed as a means to alleviate the issues associated with spatial normalization in fMRI. However, for all its appeal, a GLM-based parcellation approach introduces its own biases, in the form of a priori knowledge about the shape of Hemodynamic Response Function (HRF) and task-related signal changes, or about the subject behaviour during the task. In this paper, we introduce a data-driven version of the spectral clustering parcellation, based on Independent Component Analysis (ICA) and Partial Least Squares (PLS) instead of the GLM. First, a number of independent components are automatically selected. Seed voxels are then obtained from the associated ICA maps and we compute the PLS latent variables between the fMRI signal of the seed voxels (which covers regional variations of the HRF) and the principal components of the signal across all voxels. Finally, we parcellate all subjects data with a spectral clustering of the PLS latent variables. We present results of the application of the proposed method on both single-subject and multi-subject fMRI datasets. Preliminary experimental results, evaluated with intra-parcel variance of GLM t-values and PLS derived t-values, indicate that this data-driven approach offers improvement in terms of parcellation accuracy over GLM based techniques.

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An Interactive electronic Atlas (IeA) was developed to assist first-year nursing students with interpretation of laboratory-based prosected cadaveric material. It was designed, using pedagogically sound principles, as a student-centered resource accessible to students from a wide range of learning backgrounds. It consisted of a highly simplified interactive interface limited to essential anatomical structures and was intended for use in a blended learning situation. The IeA's nine modules mirrored the body systems covered in a Nursing Biosciences course, with each module comprising a maximum of 10 pages using the same template: an image displaying a cadaveric specimen and, in most cases, a corresponding anatomical model with navigation panes (menus) on one side. Cursor movement over the image or clicking the menu highlighted the structure with a transparent overlay and revealed a succinct functional description. The atlas was complemented by a multiple-choice database of nearly 1,000 questions using IeA images. Students' perceptions of usability and utility were measured by survey (n = 115; 57% of the class) revealing mean access of 2.3 times per week during the 12-week semester and a median time of three hours of use. Ratings for usability and utility were high, with means ranging between 4.24 and 4.54 (five-point Likert scale; 5 = strongly agree). Written responses told a similar story for both usability and utility. The role of providing basic computer-assisted learning support for a large first-year class is discussed in the context of current research into student-centered resources and blended learning in human anatomy.

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Background/Aims: Individuals who reach end-stage kidney disease (CKD5) have a high risk of vascular events that persists even after renal transplantation. This study compared the prevalence and severity of microvascular disease in transplant recipients and patients with CKD5. Methods: Individuals with a renal transplant or CKD5 were recruited consecutively from renal clinics, and underwent bilateral retinal photography (Canon CR5-45, Canon). Their retinal images were deidentified and reviewed for hypertensive/microvascular signs by an ophthalmologist and a trained grader (Wong and Mitchell classification), and for vessel caliber at a grading centre using a computer-assisted method and Knudtson’s modification of the Parr-Hubbard formula. Results: Ninety-two transplant recipients (median duration 6.4 years, range 0.8 to 28.8) and 70 subjects with CKD5 were studied. Transplant recipients were younger (p<0.001), with a higher eGFR (p< 0.001), but were just as likely to have a moderate-severe hypertensive/microvascular retinopathy (46/92, 50%) as subjects with CKD5 (38/70, 54%; OR 0.84, CI 0.45 to 1.57, p=0.64), and had similar mean arteriole and venular calibres (135.1 ± 7.5 μm and 137.9 ± 14.9 μm, p=0.12; and 199.1 ± 17.8 μm and 202.4 ± 27.8 μm, p=0.36, respectively). Arteriole and venular caliber were not different in nine patients examined before and after transplantation (p=0.62 and p=0.11, respectively). Conclusions: Hypertensive/microvascular disease occurred just as often and was generally as severe in transplant recipients and subjects with CKD5. Microvascular disease potentially contributes to increased cardiac events post- transplantation.

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BACKGROUND, AIMS AND DESIGN: The increase in mobile telephone-only households may be a source of bias for traditional landline gambling prevalence surveys. Aims were to: (1) identify Australian gambling participation and problem gambling prevalence using a dual-frame (50% landline and 50% mobile telephone) computer-assisted telephone interviewing methodology; (2) explore the predictors of sample frame and telephone status; and (3) explore the degree to which sample frame and telephone status moderate the relationships between respondent characteristics and problem gambling. SETTING AND PARTICIPANTS: A total of 2000 adult respondents residing in Australia were interviewed from March to April 2013. MEASUREMENTS: Participation in multiple gambling activities and Problem Gambling Severity Index (PGSI). FINDINGS: Estimates were: gambling participation [63.9%, 95% confidence interval (CI) = 61.4-66.3], problem gambling (0.4%, 95% CI = 0.2-0.8), moderate-risk gambling (1.9%, 95% CI = 1.3-2.6) and low-risk gambling (3.0%, 95% CI = 2.2-4.0). Relative to the landline frame, the mobile frame was more likely to gamble on horse/greyhound races [odds ratio (OR) = 1.4], casino table games (OR = 5.0), sporting events (OR = 2.2), private games (OR = 1.9) and the internet (OR = 6.5); less likely to gamble on lotteries (OR = 0.6); and more likely to gamble on five or more activities (OR = 2.4), display problem gambling (OR = 6.4) and endorse PGSI items (OR = 2.4-6.1). Only casino table gambling (OR = 2.9) and internet gambling (OR = 3.5) independently predicted mobile frame membership. Telephone status (landline frame versus mobile dual users and mobile-only users) displayed similar findings. Finally, sample frame and/or telephone status moderated the relationship between gender, relationship status, health and problem gambling (OR = 2.9-7.6). CONCLUSION: Given expected future increases in the mobile telephone-only population, best practice in population gambling research should use dual frame sampling methodologies (at least 50% landline and 50% mobile telephone) for telephone interviewing.

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La « pensée mixte » est une approche de la composition caractérisée par l’interaction de trois pensées: la pensée instrumentale, la pensée électroacoustique et la pensée informatique. Elle prend la forme d’un réseau où le compositeur fait des aller-retours entre les trois pensées et réalise des équivalences paramétriques. La pensée instrumentale se rattache à la tradition de l’écriture occidentale, la pensée électroacoustique fait allusion aux pratiques du studio analogique et de la musique acousmatique, et la pensée informatique fait référence aux pratiques numériques de la programmation visuelle et de l’analyse spectrale. Des lieux communs existent où s’opèrent l’interaction des trois pensées: la notion du studio instrumental de Ivo Malec, la notion de musique concrète instrumentale de Helmut Lachenmann, la composition assistée par ordinateur, la musique spectrale, l’approche instrumentale par montage, la musique acousmatique s’inspirant de la tradition musicale écrite et les musiques mixtes. Ces domaines constituent les influences autour desquelles j’ai composé un corpus de deux cycles d’œuvres: Les Larmes du Scaphandre et le Nano-Cosmos. L’analyse des œuvres met en évidence la notion de « pensée mixte » en abordant la pensée électroacoustique dans ma pratique instrumentale, la pensée informatique dans ma pratique musicale, et la pensée instrumentale dans ma pratique électroacoustique.

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The evaluation of changes in Intervertebral Discs (IVDs) with 3D Magnetic Resonance (MR) Imaging (MRI) can be of interest for many clinical applications. This paper presents the evaluation of both IVD localization and IVD segmentation methods submitted to the Automatic 3D MRI IVD Localization and Segmentation challenge, held at the 2015 International Conference on Medical Image Computing and Computer Assisted Intervention (MICCAI2015) with an on-site competition. With the construction of a manually annotated reference data set composed of 25 3D T2-weighted MR images acquired from two different studies and the establishment of a standard validation framework, quantitative evaluation was performed to compare the results of methods submitted to the challenge. Experimental results show that overall the best localization method achieves a mean localization distance of 0.8 mm and the best segmentation method achieves a mean Dice of 91.8%, a mean average absolute distance of 1.1 mm and a mean Hausdorff distance of 4.3 mm, respectively. The strengths and drawbacks of each method are discussed, which provides insights into the performance of different IVD localization and segmentation methods.

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La « pensée mixte » est une approche de la composition caractérisée par l’interaction de trois pensées: la pensée instrumentale, la pensée électroacoustique et la pensée informatique. Elle prend la forme d’un réseau où le compositeur fait des aller-retours entre les trois pensées et réalise des équivalences paramétriques. La pensée instrumentale se rattache à la tradition de l’écriture occidentale, la pensée électroacoustique fait allusion aux pratiques du studio analogique et de la musique acousmatique, et la pensée informatique fait référence aux pratiques numériques de la programmation visuelle et de l’analyse spectrale. Des lieux communs existent où s’opèrent l’interaction des trois pensées: la notion du studio instrumental de Ivo Malec, la notion de musique concrète instrumentale de Helmut Lachenmann, la composition assistée par ordinateur, la musique spectrale, l’approche instrumentale par montage, la musique acousmatique s’inspirant de la tradition musicale écrite et les musiques mixtes. Ces domaines constituent les influences autour desquelles j’ai composé un corpus de deux cycles d’œuvres: Les Larmes du Scaphandre et le Nano-Cosmos. L’analyse des œuvres met en évidence la notion de « pensée mixte » en abordant la pensée électroacoustique dans ma pratique instrumentale, la pensée informatique dans ma pratique musicale, et la pensée instrumentale dans ma pratique électroacoustique.