O crédito à habitação : uma evidência empírica em Portugal

Mestrado em Contabilidade e Gestão de Instituições Financeiras

sMapReduce: a programming pattern for wireless sensor networks

Wireless Sensor Networks (WSNs) are increasingly used in various application domains like home-automation, agriculture, industries and infrastructure monitoring. As applications tend to leverage larger geographical deployments of sensor networks, the availability of an intuitive and user friendly programming abstraction becomes a crucial factor in enabling faster and more efficient development, and reprogramming of applications. We propose a programming pattern named sMapReduce, inspired by the Google MapReduce framework, for mapping application behaviors on to a sensor network and enabling complex data aggregation. The proposed pattern requires a user to create a network-level application in two functions: sMap and Reduce, in order to abstract away from the low-level details without sacrificing the control to develop complex logic. Such a two-fold division of programming logic is a natural-fit to typical sensor networking operation which makes sensing and topological modalities accessible to the user.

Enhancing Multimodal Silent Speech Interfaces With Feature Selection

In research on Silent Speech Interfaces (SSI), different sources of information (modalities) have been combined, aiming at obtaining better performance than the individual modalities. However, when combining these modalities, the dimensionality of the feature space rapidly increases, yielding the well-known "curse of dimensionality". As a consequence, in order to extract useful information from this data, one has to resort to feature selection (FS) techniques to lower the dimensionality of the learning space. In this paper, we assess the impact of FS techniques for silent speech data, in a dataset with 4 non-invasive and promising modalities, namely: video, depth, ultrasonic Doppler sensing, and surface electromyography. We consider two supervised (mutual information and Fisher's ratio) and two unsupervised (meanmedian and arithmetic mean geometric mean) FS filters. The evaluation was made by assessing the classification accuracy (word recognition error) of three well-known classifiers (knearest neighbors, support vector machines, and dynamic time warping). The key results of this study show that both unsupervised and supervised FS techniques improve on the classification accuracy on both individual and combined modalities. For instance, on the video component, we attain relative performance gains of 36.2% in error rates. FS is also useful as pre-processing for feature fusion. Copyright © 2014 ISCA.

Institutional and matrix support and its relationship with primary healthcare

OBJECTIVE To analyze whether the level of institutional and matrix support is associated with better certification of primary healthcare teams.METHODS In this cross-sectional study, we evaluated two kinds of primary healthcare support – 14,489 teams received institutional support and 14,306 teams received matrix support. Logistic regression models were applied. In the institutional support model, the independent variable was “level of support” (as calculated by the sum of supporting activities for both modalities). In the matrix support model, in turn, the independent variables were the supporting activities. The multivariate analysis has considered variables with p < 0.20. The model was adjusted by the Hosmer-Lemeshow test.RESULTS The teams had institutional and matrix supporting activities (84.0% and 85.0%), respectively, with 55.0% of them performing between six and eight activities. For the institutional support, we have observed 1.96 and 3.77 chances for teams who had medium and high levels of support to have very good or good certification, respectively. For the matrix support, the chances of their having very good or good certification were 1.79 and 3.29, respectively. Regarding to the association between institutional support activities and the certification, the very good or good certification was positively associated with self-assessment (OR = 1.95), permanent education (OR = 1.43), shared evaluation (OR = 1.40), and supervision and evaluation of indicators (OR = 1.37). In regards to the matrix support, the very good or good certification was positively associated with permanent education (OR = 1.50), interventions in the territory (OR = 1.30), and discussion in the work processes (OR = 1.23).CONCLUSIONS In Brazil, supporting activities are being incorporated in primary healthcare, and there is an association between the level of support, both matrix and institutional, and the certification result.

A Logic and tool for local reasoning about security protocols

Trabalho apresentado no âmbito do Mestrado em Engenharia Informática, como requisito parcial para obtenção do grau de Mestre em Engenharia Informática

The impact of Sinogram-Affirmed Iterative Reconstruction on patient dose and image quality compared to filtered back projection: a narrative review

Objective: Summarize all relevant findings in published literature regarding the potential dose reduction related to image quality using Sinogram-Affirmed Iterative Reconstruction (SAFIRE) compared to Filtered Back Projection (FBP). Background: Computed Tomography (CT) is one of the most used radiographic modalities in clinical practice providing high spatial and contrast resolution. However it also delivers a relatively high radiation dose to the patient. Reconstructing raw-data using Iterative Reconstruction (IR) algorithms has the potential to iteratively reduce image noise while maintaining or improving image quality of low dose standard FBP reconstructions. Nevertheless, long reconstruction times made IR unpractical for clinical use until recently. Siemens Medical developed a new IR algorithm called SAFIRE, which uses up to 5 different strength levels, and poses an alternative to the conventional IR with a significant reconstruction time reduction. Methods: MEDLINE, ScienceDirect and CINAHL databases were used for gathering literature. Eleven articles were included in this review (from 2012 to July 2014). Discussion: This narrative review summarizes the results of eleven articles (using studies on both patients and phantoms) and describes SAFIRE strengths for noise reduction in low dose acquisitions while providing acceptable image quality. Conclusion: Even though the results differ slightly, the literature gathered for this review suggests that the dose in current CT protocols can be reduced at least 50% while maintaining or improving image quality. There is however a lack of literature concerning paediatric population (with increased radiation sensitivity). Further studies should also assess the impact of SAFIRE on diagnostic accuracy.

A comparison of Sinogram Affirmed Iterative Reconstruction and filtered back projection on image quality and dose reduction in paediatric head CT: a phantom study

Background: Computed tomography (CT) is one of the most used modalities for diagnostics in paediatric populations, which is a concern as it also delivers a high patient dose. Research has focused on developing computer algorithms that provide better image quality at lower dose. The iterative reconstruction algorithm Sinogram-Affirmed Iterative Reconstruction (SAFIRE) was introduced as a new technique that reduces noise to increase image quality. Purpose: The aim of this study is to compare SAFIRE with the current gold standard, Filtered Back Projection (FBP), and assess whether SAFIRE alone permits a reduction in dose while maintaining image quality in paediatric head CT. Methods: Images were collected using a paediatric head phantom using a SIEMENS SOMATOM PERSPECTIVE 128 modulated acquisition. 54 images were reconstructed using FBP and 5 different strengths of SAFIRE. Objective measures of image quality were determined by measuring SNR and CNR. Visual measures of image quality were determined by 17 observers with different radiographic experiences. Images were randomized and displayed using 2AFC; observers scored the images answering 5 questions using a Likert scale. Results: At different dose levels, SAFIRE significantly increased SNR (up to 54%) in the acquired images compared to FBP at 80kVp (5.2-8.4), 110kVp (8.2-12.3), 130kVp (8.8-13.1). Visual image quality was higher with increasing SAFIRE strength. The highest image quality was scored with SAFIRE level 3 and higher. Conclusion: The SAFIRE algorithm is suitable for image noise reduction in paediatric head CT. Our data demonstrates that SAFIRE enhances SNR while reducing noise with a possible reduction of dose of 68%.

ECG-based biometrics: A real time classification approach

Behavioral biometrics is one of the areas with growing interest within the biosignal research community. A recent trend in the field is ECG-based biometrics, where electrocardiographic (ECG) signals are used as input to the biometric system. Previous work has shown this to be a promising trait, with the potential to serve as a good complement to other existing, and already more established modalities, due to its intrinsic characteristics. In this paper, we propose a system for ECG biometrics centered on signals acquired at the subject's hand. Our work is based on a previously developed custom, non-intrusive sensing apparatus for data acquisition at the hands, and involved the pre-processing of the ECG signals, and evaluation of two classification approaches targeted at real-time or near real-time applications. Preliminary results show that this system leads to competitive results both for authentication and identification, and further validate the potential of ECG signals as a complementary modality in the toolbox of the biometric system designer.

Neuroartropatia de Charcot do pé diabético: identificação, tratamento conservador e prevenção das suas complicações

Mestrado em Gestão e Avaliação de Tecnologias em Saúde

Radioimunoterapia: uma abordagem terapêutica promissora no tratamento do carcinoma do ovário

O cancro do ovário é a neoplasia ginecológica com maior índice de mortalidade entre a população do sexo feminino apesar dos consideráveis progressos verificados no seu tratamento. Caso o diagnóstico seja precoce, a taxa de sobrevida é bastante elevada, mas o cancro do ovário primário é assintomático e na maioria das vezes só é diagnosticado numa fase avançada da doença, resultando num prognóstico pouco favorável. A falta de especificidade das modalidades terapêuticas associada à heterogeneidade das células oncológicas tem limitado a terapia do cancro do ovário. Alguns dos avanços clínicos mais promissores no tratamento do cancro são as terapêuticas dirigidas a alvos específicos, especialmente proteínas sobre expressas em vários tipos de células epiteliais. Neste contexto, a radioimunoterapia com anticorpos monoclonais tem sido explorada nos carcinomas epiteliais que constituem cerca de 90% das neoplasias do ovário. Esta estratégia terapêutica, que tira partido da ação combinada da radiotoxicidade associada aos radionuclídeos para terapia e dos efeitos citotóxicos do anticorpo, pode constituir uma alternativa às terapias convencionais, potenciando a eficácia do tratamento. Neste artigo são abordados aspetos relacionados com o cancro do ovário, nomeadamente o seu diagnóstico e terapia. São ainda revistos, de forma breve, alguns estudos clínicos em que a eficácia de anticorpos monoclonais marcados com radionuclídeos para terapêutica foi avaliada no cancro do ovário.

TERT Promoter Mutations Are a Major Indicator of Poor Outcome in Differentiated Thyroid Carcinomas

Context: Telomerase promoter mutations (TERT) were recently described in follicular cell-derived thyroid carcinomas (FCDTC) and seem to be more prevalent in aggressive cancers. Objectives: We aimed to evaluate the frequency of TERT promoter mutations in thyroid lesions and to investigate the prognostic significance of such mutations in a large cohort of patients with differentiated thyroid carcinomas (DTCs). Design: This was a retrospective observational study. Setting and Patients: We studied 647 tumors and tumor-like lesions. A total of 469 patients with FCDTC treated and followed in five university hospitals were included. Mean follow-up (±SD) was 7.8 ± 5.8 years. Main Outcome Measures: Predictive value of TERT promoter mutations for distant metastasization, disease persistence at the end of follow-up, and disease-specific mortality. Results: TERT promoter mutations were found in 7.5% of papillary carcinomas (PTCs), 17.1% of follicular carcinomas, 29.0% of poorly differentiated carcinomas, and 33.3% of anaplastic thyroid carcinomas. Patients with TERT-mutated tumors were older (P < .001) and had larger tumors (P = .002). In DTCs, TERT promoter mutations were significantly associated with distant metastases (P < .001) and higher stage (P < .001). Patients with DTC harboring TERT promoter mutations were submitted to more radioiodine treatments (P = .009) with higher cumulative dose (P = .004) and to more treatment modalities (P = .001). At the end of follow-up, patients with TERT-mutated DTCs were more prone to have persistent disease (P = .001). TERT promoter mutations were significantly associated with disease-specific mortality [in the whole FCDTC (P < .001)] in DTCs (P < .001), PTCs (P = .001), and follicular carcinomas (P < .001). After adjusting for age at diagnosis and gender, the hazard ratio was 10.35 (95% confidence interval 2.01–53.24; P = .005) in DTC and 23.81 (95% confidence interval 1.36–415.76; P = .03) in PTCs. Conclusions: TERT promoter mutations are an indicator of clinically aggressive tumors, being correlated with worse outcome and disease-specific mortality in DTC. TERT promoter mutations have an independent prognostic value in DTC and, notably, in PTC.

The role of molecular imaging in modern drug development

Drug development represents a highly complex, inefficient and costly process. Over the past decade, the widespread use of nuclear imaging, owing to its functional and molecular nature, has proven to be a determinant in improving the efficiency in selecting the candidate drugs that should either be abandoned or moved forward into clinical trials. This helps not only with the development of safer and effective drugs but also with the shortening of time-to-market. The modern concept and future trends concerning molecular imaging will assumedly be hybrid or multimodality imaging, including combinations between high sensitivity and functional (molecular) modalities with high spatial resolution and morphological techniques.

Protocolo de fisioterapia, com auxílio de biofeedback electromiográfico, em utentes com disfunções do ombro: efeitos na dor, funcionalidade e estabilidade dinâmica

RESUMO: Introdução: A dor e disfunções do movimento no complexo articular do ombro (CAO) são comuns e debilitantes. O uso de exercícios segundo os pressupostos de estabilidade dinâmica (ED), com auxílio de Biofeedback electromiográfico (BEMG) tem vindo a ser referido, como uma forma de aumentar a efectividade da intervenção nas disfunções do complexo articular do ombro (DCAO)Objectivo Principal: Estudar os efeitos de um protocolo de intervenção, com BEMG, cujas finalidades foram abolir a dor, aumentar a funcionalidade e a ED da omoplata, em utentes com DCAO. Objectivos secundários: Comparar os subgrupos e quanto às características, resultados, tempos de intervenção total e até atingir critérios de alta; Comparar os resultados nos momentos inicial e final. Métodos: Foi realizado um coorte clínico, longitudinal, retrospectivo, observacional, analítico. A amostra foi constituída por 82 sujeitos, divididos em dois subgrupos (n=53 SCSA e n=29 IGU). Os instrumentos de medida utilizados foram a EVA, o DASH, o SPADI e o BEMG. Foi seguido o protocolo de ED proposto por Santos e Matias (2007), de acordo com as 3 fases de intervenção por eles descritas, realizando uma sessão semanal, monitorizando exercícios que seguem estes princípios, com BEMG. Foram avaliadas as variáveis dor, postura, padrão de recrutamento, controlo motor, posição inicial da omoplata (PIO), amplitudes articulares (AA’s), força muscular (FM) e postura. Para analisar os dados, recorreu-se a estatística descritiva e inferencial. Resultados: A intervenção foi efectiva na abolição da dor no momento (0,43 para 0,00/10EVA no subgrupo SCSA e 0,66 para 0,00/10EVA no subgrupo IGU) na pior dor (5,47/10EVA para 0,06/10EVA no subgrupo SCSA e 5,28/10 para 0,14/10 no subgrupo IGU), no aumento da função (28,57 para 0,66/100DASH e 39,00 para 0,63/100SAPDI no subgrupo SCSA e 25,80 para 0,38/100DASH e 28,19 para 0,39/100 no subgrupo IGU) e no aumento da ED da omoplata com normalização do padrão de recrutamento, controlo motor, PIO dentro do espectro de normalidade e boa capacidade de controlar a sua posição, ao longo do movimento do membro superior (MS). A intervenção proporcionou, ainda a normalização das AA’s, FM e autocorrecção postural. O tempo médio de intervenção foi de 6,45semanas no subgrupo SCSA e 5,83sem no subgrupo IGU. Estes resultados são semelhantes comparativamente a estudos que utilizaram uma intervenção baseada nos mesmos princípios (Matias e Cruz, 2004; Cunha e Matias, 2006; Santos e Matias, 2007; Rodrigues e Matias, 2009). Conclusão: O protocolo de intervenção aplicado, com uso de exercícios baseados nos princípios da ED e uso de BEMG, permitiu o alcance dos objectivos, junto de utentes com DCAO (SCSA e IGU). Verificou-se que, independentemente da condição, os resultados foram idênticos em ambos subgrupos, não apresentando diferenças significativas entre as variáveis de medida final, o tempo total de intervenção e os tempos até atingir os critérios de alta, expecto para a Dor, sendo este superior no subgrupo SCSA.---------------------------------------- ABSTRACT:Introduction: Movement disorders and pain in the shoulder joint complex (SJC) are common and debilitating. The use of exercises under the premises of dynamic stability (DS), with the aid of electromyographic biofeedback (EMGBF) has been mentioned as a way to increase the effectiveness of the intervention in disorders of the shoulder joint complex (DSJC) Main Objective: To evaluate the results of an intervention protocol, with EMGBF whose aims were to abolish the pain, increase functionality and DS of the scapula in patients with DSJC. Objectives: To compare the subgroups and the characteristics, outcomes, and total intervention times to reach discharge criteria; to compare the results at the beginning and at the end. Methods: We conducted a clinical cohort, longitudinal, retrospective, observational analysis. The sample consisted of 82 subjects, divided into two subgroups (n = 53 shoulder impingement syndrome SIS n = 29 shoulder joint instability SJI). The measurement instruments used were the VAS, DASH, SPADI, and EMGBF. It was followed the DS protocol proposed by Santos and Matias (2007), according to the three phases of intervention, described by performing a weekly session, monitoring exercises that follow these principles, with EMGBF. The variables were pain, posture, recruitment pattern, motor control, the initial position of the scapula (IPS), range of motion (ROM), muscular strength (MS) and posture. To analyze the data, we used the descriptive and inferential statistics. Results: The intervention was effective in abolishing the pain at the time (0.43 to 0.00/10 VAS in the SIS subgroup and 0.66 to 0.00/10 VAS in the SJI subgroup) in worst pain (5.47 to 0,06/10 VAS in the SIS subgroup and 5.28/ to 0.14/10 VAS in the SJI subgroup), increasing the function (28,57 to 0,66/100 DASH and 39,00 to 0,63/100 SAPDI in the SIS subgroup and 25,80 to 0,38/100 DASH and 28,19 to 0,39/100 SPADI in the SJI subgroup) and the increase in DS of the scapula with normalization of the pattern recruitment, motor control, IPS within the spectrum of normalcy and good ability to control its position along the movement of the upper limb (UL). The intervention provided, although the normalization of ROM, MS and self-correcting posture. The average length of intervention was 6.45 weeks in the SIS subgroup and 5.83 in the IS subgroup. These results are comparable with similar studies that used an intervention based on the same principles (Matias e Cruz, 2004; Cunha e Matias, 2006; Santos e Matias, 2007; Rodrigues e Matias, 2009). Conclusion: The intervention protocol implemented with the use of exercises based on the principles of DS and the use of EMGBF was effective, allowing the accomplishment of goals, in patients with DSJC (SIS and SJI). It was found that, regardless of condition, the results were identical in both groups, showing no significant differences between the variables of the final measure, the total time of intervention and the times to reach discharge criteria, except for pain, which was higher in the SIS subgroup.

Combining sparse and dense methods in 6D Visual Odometry

13th International Conference on Autonomous Robot Systems (Robotica), 2013, Lisboa

Derrame Pericárdico Recidivante. Um Caso de Angiosarcoma Cardíaco

A case of angiosarcoma of the right atrium in a 59-year-old woman is reported, presenting as a recurrent hematic pericardial effusion. The usefulness of echocardiography in making the diagnosis is emphasized. The tumor was already disseminated at the time of the diagnosis. The patient was on palliative therapy, dying a few months later. The histological examination was done at autopsy. This case highlights the difficulty in diagnosis and the various modalities available for an accurate diagnosis of a rare clinical entity. It has a rapid and aggressive course with a very poor prognosis.