840 resultados para Computer-assisted instruction--Evaluation.


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AIMS: We report the outcomes of a large lung stereotactic ablative body radiotherapy (SABR) programme for primary non-small cell lung cancer (NSCLC) and pulmonary metastases. The primary study aim was to identify factors predictive for local control.

MATERIALS AND METHODS: In total, 311 pulmonary tumours in 254 patients were treated between 2008 and 2011 with SABR using 48-60 Gy in four to five fractions. Local, regional and distant failure data were collected prospectively, whereas other end points were collected retrospectively. Potential clinical and dosimetric predictors of local control were evaluated using univariate and multivariate analyses.

RESULTS: Of the 311 tumours, 240 were NSCLC and 71 were other histologies. The 2 year local control rate was 96% in stage I NSCLC, 76% in colorectal cancer (CRC) metastases and 91% in non-lung/non-CRC metastases. Predictors of better local control on multivariate analysis were non-CRC tumours and a larger proportion of the planning target volume (PTV) receiving ≥100% of the prescribed dose (higher PTV V100). Among the 45 CRC metastases, a higher PTV V100 and previous chemotherapy predicted for better local control.

CONCLUSIONS: Lung SABR of 48-60 Gy/four to five fractions resulted in high local control rates for all tumours except CRC metastases. Covering more of the PTV with the prescription dose (a higher PTV V100) also resulted in superior local control.

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PURPOSE: This systematic review aimed to report and explore the survival of dental veneers constructed from non-feldspathic porcelain over 5 and 10 years.

MATERIALS AND METHODS: A total of 4,294 articles were identified through a systematic search involving all databases in the Cochrane Library, MEDLINE (OVID), EMBASE, Web of Knowledge, specific journals (hand-search), conference proceedings, clinical trials registers, and collegiate contacts. Articles, abstracts, and gray literature were sought by two independent researchers. There were no language limitations. One hundred sixteen studies were identified for full-text assessment, with 10 included in the analysis (5 qualitative, 5 quantitative). Study characteristics and survival (Kaplan-Meier estimated cumulative survival and 95% confidence interval [CI]) were extracted or recalculated. A failed veneer was one which required an intervention that disrupted the original marginal integrity, had been partially or completely lost, or had lost retention more than twice. A meta-analysis and sensitivity analysis of Empress veneers was completed, with an assessment of statistical heterogeneity and publication bias. Clinical heterogeneity was explored for results of all veneering materials from included studies.

RESULTS: Within the 10 studies, veneers were fabricated with IPS Empress, IPS Empress 2, Cerinate, and Cerec computer-aided design/computer-assisted manufacture (CAD/CAM) materials VITA Mark I, VITA Mark II, Ivoclar ProCad. The meta-analysis showed the pooled estimate for Empress veneers to be 92.4% (95% CI: 89.8% to 95.0%) for 5-year survival and 66% to 94% (95% CI: 55% to 99%) for 10 years. Data regarding other non-feldspathic porcelain materials were lacking, with only a single study each reporting outcomes for Empress 2, Cerinate, and various Cerec porcelains over 5 years. The sensitivity analysis showed data from one study had an influencing and stabilizing effect on the 5-year pooled estimate.

CONCLUSION: The long-term outcome (> 5 years) of non-feldspathic porcelain veneers is sparsely reported in the literature. This systematic review indicates that the 5-year cumulative estimated survival for etchable non-feldspathic porcelain veneers is over 90%. Outcomes may prove clinically acceptable with time, but evidence remains lacking and the use of these materials for veneers remains experimental.

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Poverty means more than having a low income and includes exclusion from a minimally accepted way of life. It is now common practice in Europe to measure progress against poverty in terms of low income, material deprivation rates and some combination of both. This makes material deprivation indicators, and their selection, highly significant in its own right. The ‘consensual poverty’ approach is to identify deprivation items which a majority of the population agree constitute life’s basic necessities, accepting that these items will need revised over time to reflect social change. Traditionally, this has been carried out in the UK through specialised poverty surveys using a Sort Card (SC) technique.

Based on analysis of a 2012 omnibus survey, and discussions with three interviewers, this article examines how perception of necessities is affected by mode of administration – SC and Computer Assisted Personal Interviewing (CAPI). More CAPI respondents scored deprivation items necessary. Greatest disparities are in material items where 25 out of 32 items were significantly higher via CAPI. Closer agreement is found in social participation with 3 out of 14 activities significantly different. Consensus is higher on children’s material deprivation.
We consider influencing variables which could account for the disparities and believe that the SC method produces a more considered response. However, in light of technological advances, we question how long the SC method will remain socially acceptable. This paper concludes that the CAPI method can be easily modified without compromising the benefits of the SC method in capturing thoughtful responses.

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Purpose - The purpose is to unearth managerial representations of achieving competitive advantage in relation to architectural firms operating within the United Kingdom (UK).
Design/Methodology/Approach - A sequential qualitative methodology is applied, underpinned by nine managerial interviews in five architectural practices; all of which are analysed using computer assisted qualitative data analysis software.
Findings - 108 representations are identified with highly rated concepts discussed in detail. Subsequently, the leading concepts include reputation, client satisfaction, fees and staff resources, among others.
Research Limitations/Implications - There are numerous studies conducted on this subject; however, there has been no research done to date documenting managerial representations within the UK on achieving competitive advantage in the context of architectural firms.
Practical Implications – The need for architectural firms to develop a competitive advantage within their market sector is ever more apparent, particularly during times of increased competitiveness.
Originality/Value – This paper fulfils a gap in knowledge by contributing to underlying research on the subject of competitive advantage, but focusing on the managerial representations, specifically within UK practices. The findings are of relevance to architects in both the UK and beyond, as well as perhaps forming the basis of identifying further research with the area.

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Wavelet entropy assesses the degree of order or disorder in signals and presents this complex information in a simple metric. Relative wavelet entropy assesses the similarity between the spectral distributions of two signals, again in a simple metric. Wavelet entropy is therefore potentially a very attractive tool for waveform analysis. The ability of this method to track the effects of pharmacologic modulation of vascular function on Doppler blood velocity waveforms was assessed. Waveforms were captured from ophthalmic arteries of 10 healthy subjects at baseline, after the administration of glyceryl trinitrate (GTN) and after two doses of N(G)-nitro-L-arginine-methyl ester (L-NAME) to produce vasodilation and vasoconstriction, respectively. Wavelet entropy had a tendency to decrease from baseline in response to GTN, but significantly increased after the administration of L-NAME (mean: 1.60 ± 0.07 after 0.25 mg/kg and 1.72 ± 0.13 after 0.5 mg/kg vs. 1.50 ± 0.10 at baseline, p < 0.05). Relative wavelet entropy had a spectral distribution from increasing doses of L-NAME comparable to baseline, 0.07 ± 0.04 and 0.08 ± 0.03, respectively, whereas GTN had the most dissimilar spectral distribution compared with baseline (0.17 ± 0.08, p = 0.002). Wavelet entropy can detect subtle changes in Doppler blood velocity waveform structure in response to nitric-oxide-mediated changes in arteriolar smooth muscle tone.

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A análise da mobilidade seminal é uma ferramenta importante para reprodução em aquacultura. Esta é uma técnica in vitro que auxilia a estabulação, manutenção e selecção de lotes de reprodutores. A análise de mobilidade seminal pode tornar-se potencialmente uma ferramenta para o melhoramento das condições do ambiente de fertilização. A utilização do software CASA (Computer Assisted Sperm Analysis) revolucionou a descrição e quantificação específica da mobilidade seminal. A maioria da informação recolhida sobre mobilidade de sémen de peixes baseia-se em espécies de água doce, pelo que é crucial conhecer as condições óptimas de activação da mobilidade de espermatozóides para novas espécies de de água salgada de interesse em aquacultura tal como Solea senegalensis. A optimização das condições de fertilização desta espécie é particularmente importante já que os lotes de reprodutores em cativeiro podem desenvolver disfunções reprodutoras. Este trabalho teve como objectivo realizar a avaliação das condições óptimas de activação da mobilidade do sémen em S. senegalensis em termos de temperatura, salinidade e pH. O segundo objectivo foi realizar a avaliação da influência de fluido ovárico homólogo (S. senegalensis) e heterólogo (Epinephelus marginatus) na mobilidade seminal de S. senegalensis. Deste modo foram realizados dois conjuntos de experiências: 1) mobilidade de sémen de 7 machos analisado através do CASA em diferentes temperaturas, salinidades e pH, 2) mobilidade de sémen de 8 machos activados na presença de diferentes concentrações de fluido ovárico. Os parâmetros do CASA foram registados e posteriormente analisados através de médias e cluster analysis. Concluiu-se que temperaturas mais elevadas (20 ºC) e baixas salinidades (25 ‰ e 30 ‰) da solução de activação ocorre um melhoramento das características de mobilidade seminal, tal como a velocidade. A presença de fluido ovárico em baixas concentrações melhora as características da mobilidade seminal assim como a longevidade dos espermatozóides. O fluido ovárico é consequentemente um factor que estimula a mobilidade seminal que tem sido negligenciado em estudos anteriores. Este estudo demonstrou que durante a época de reprodução a temperatura da água (20 ºC) e a salinidade (25 ‰ e 30 ‰) no tanque são os principais factores que melhoram a activação da mobilidade do sémen, sendo consequentemente uma contribuição importante para compreender a dinâmica do processo de fertilização em S. senegalensis.

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Dissertação de mestrado, Aquacultura, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2015

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A previous paper showed that young children performed better when working as individuals rather than in pairs on a drill and practice program. This paper reports an analysis of behaviour and talk for individuals and single sex pairs using a computer-based drill and practice activity to explain differences in performance. Results indicated that individuals were more likely to be task-focused and to complete tasks successfully than children working in pairs. Differences were found in off-task activity, behaviours and type of talk. Grouping and verbal interaction are discussed in relation to the type of task/program that children are asked to undertake, and how both task and peer presence may constrain the child's task focus and performance when reinforcing pre-existing knowledge.

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Multi-parametric magnetic resonance imaging (mp-MRI) has become an increasingly important method for detecting and treating prostate cancer. Transrectal ultrasound (TRUS) is the most commonly used method for guiding prostate needle biopsy and remains the gold standard for diagnosis of prostate cancer. MRI-to-TRUS image reg- istration is an important technology for enabling computer-assisted targeting of the majority of prostate lesions that are visible in MRI but not independently distinguishable in TRUS images. The aim of this study was to estimate the needle placement accuracy of an image guidance system (SmartTargetÒ), developed by our research group, using a surgical training phantom.

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The use of Laptops and the Internet has produced the technological conditions for instructors and students can take advantage from the diversity of online information, communication, collaboration and sharing with others. The integration of Internet services in the teaching practices can be responsible for thematic, social and digital improvement for the agents involved. There are many benefits when we use a Learning Management Systems (LMS) such as Moodle, to support the lectures in higher education. We also will consider its implications for student support and online interaction, leading educational agents to a collaborating of different learning environments, where they can combine face-to-face instruction with computer-mediated instruction, blended-learning, and increases the possibilities for better quality and quantity of human communication in a learning background. In general components of learning management systems contain synchronous and asynchronous communication tools, management features, and assessment utilities. These assessment utilities allow lecturers to systematize basic assessment tasks. Assessments can be straightaway delivered to the student, and upon conclusion, immediately returned with grades and detailed feedback. Therefore learning management systems can also be used for assessment purposes in Higher Education.

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The aim of this study was to evaluate the combination of abdominoplasty with liposuction of both flanks with regards to length of scar, complications, and patient's satisfaction. A retrospective analysis of 35 patients who underwent esthetic abdominoplasty at our institution between 2002 and 2004 was performed. Thirteen patients underwent abdominoplasty with liposuction of both flanks, 22 patients underwent conventional abdominoplasty. Liposuction of the flanks did not increase the rate of complications of the abdominoplasty procedures. We found a tendency toward shorter scars in patients who underwent abdominoplasty combined with liposuction of the flanks. Implementation of 3-dimensional laser surface scanning to objectify the postoperative outcomes, documented a comparable degree of flatness of the achieved body contouring in both procedures. 3-dimensional laser surface scanning can be a valuable tool to objectify assessment of postoperative results.

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Studies evaluating the mechanical behavior of the trabecular microstructure play an important role in our understanding of pathologies such as osteoporosis, and in increasing our understanding of bone fracture and bone adaptation. Understanding of such behavior in bone is important for predicting and providing early treatment of fractures. The objective of this study is to present a numerical model for studying the initiation and accumulation of trabecular bone microdamage in both the pre- and post-yield regions. A sub-region of human vertebral trabecular bone was analyzed using a uniformly loaded anatomically accurate microstructural three-dimensional finite element model. The evolution of trabecular bone microdamage was governed using a non-linear, modulus reduction, perfect damage approach derived from a generalized plasticity stress-strain law. The model introduced in this paper establishes a history of microdamage evolution in both the pre- and post-yield regions

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Red blood cell (RBC) parameters such as morphology, volume, refractive index, and hemoglobin content are of great importance for diagnostic purposes. Existing approaches require complicated calibration procedures and robust cell perturbation. As a result, reference values for normal RBC differ depending on the method used. We present a way for measuring parameters of intact individual RBCs by using digital holographic microscopy (DHM), a new interferometric and label-free technique with nanometric axial sensitivity. The results are compared with values achieved by conventional techniques for RBC of the same donor and previously published figures. A DHM equipped with a laser diode (lambda = 663 nm) was used to record holograms in an off-axis geometry. Measurements of both RBC refractive indices and volumes were achieved via monitoring the quantitative phase map of RBC by means of a sequential perfusion of two isotonic solutions with different refractive indices obtained by the use of Nycodenz (decoupling procedure). Volume of RBCs labeled by membrane dye Dil was analyzed by confocal microscopy. The mean cell volume (MCV), red blood cell distribution width (RDW), and mean cell hemoglobin concentration (MCHC) were also measured with an impedance volume analyzer. DHM yielded RBC refractive index n = 1.418 +/- 0.012, volume 83 +/- 14 fl, MCH = 29.9 pg, and MCHC 362 +/- 40 g/l. Erythrocyte MCV, MCH, and MCHC achieved by an impedance volume analyzer were 82 fl, 28.6 pg, and 349 g/l, respectively. Confocal microscopy yielded 91 +/- 17 fl for RBC volume. In conclusion, DHM in combination with a decoupling procedure allows measuring noninvasively volume, refractive index, and hemoglobin content of single-living RBCs with a high accuracy.

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Digital holographic microscopy (DHM) allows optical-path-difference (OPD) measurements with nanometric accuracy. OPD induced by transparent cells depends on both the refractive index (RI) of cells and their morphology. This Letter presents a dual-wavelength DHM that allows us to separately measure both the RI and the cellular thickness by exploiting an enhanced dispersion of the perfusion medium achieved by the utilization of an extracellular dye. The two wavelengths are chosen in the vicinity of the absorption peak of the dye, where the absorption is accompanied by a significant variation of the RI as a function of the wavelength.

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We investigated the neural basis for spontaneous chemo-stimulated increases in ventilation in awake, healthy humans. Blood oxygen level dependent (BOLD) functional MRI was performed in nine healthy subjects using T2 weighted echo planar imaging. Brain volumes (52 transverse slices, cortex to high spinal cord) were acquired every 3.9 s. The 30 min paradigm consisted of six, 5-min cycles, each cycle comprising 45 s of hypoxic-isocapnia, 45 s of isooxic-hypercapnia and 45 s of hypoxic-hypercapnia, with 55 s of non-stimulatory hyperoxic-isocapnia (control) separating each stimulus period. Ventilation was significantly (p<0.001) increased during hypoxic-isocapnia, isooxic-hypercapnia and hypoxic-hypercapnia (17.0, 13.8, 24.9 L/min respectively) vs. control (8.4 L/min) and was associated with significant (p<0.05, corrected for multiple comparisons) signal increases within a bilateral network that included the basal ganglia, thalamus, red nucleus, cerebellum, parietal cortex, cingulate and superior mid pons. The neuroanatomical structures identified provide evidence for the spontaneous control of breathing to be mediated by higher brain centres, as well as respiratory nuclei in the brainstem.