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There is no doubt that computer architecture represents a core course in computer science curriculum. A computer architecture course involves mainly the microprocessor structure and operation which constitutes the heart of the whole system. Due to microprocessor complexity, a number of simulation software solutions have been developed for supporting the corresponding courses. On the other hand, simulators offer only a visual environment where the students cannot change operational or structural characteristics for studying the corresponding microprocessor behavior. Moreover and much more important is the fact that students cannot demystify the physical level where bit manipulation takes place. A novel and low cost approach for studying in depth microprocessor structure and operation at programming and hardware level is presented and finally proposed for the very first time in this paper. The student uses programmable hardware modules for developing the internal structure of a microprocessor. Finally, the developed microprocessor can be studied from programmer's or developer's view. [ABSTRACT FROM AUTHOR]

OBJECTIVE The European Forsteo Observational Study (EFOS) examined the long-term fractures, back pain (BP), health-related quality of life (HRQoL) and compliance with treatment in post-menopausal women with osteoporosis (OP) treated with teriparatide (TPTD) for the maximum approved period (18 months), with follow-up for a further 18 months. This paper describes the 18 month follow-up outcomes of Greek patients completing TPTD treatment. METHOD EFOS, a 3-year, multinational, observational study recorded the incidence of clinical vertebral and non-vertebral fractures, BP [using a 100 mm Visual Analogue Scale (VAS)], and HRQoL [using the EuroQol Standardized Questionnaire (EQ-5D)]. Changes from baseline in BP and EQ parameters were analyzed using a repeated measures model. Improvement over the baseline in frequency and severity of BP and limitations in activity due to BP were assessed using the sign test. RESULTS Of the 301 Greek women aged 69.5±8.5 years enrolled in the study, 83.7% reported previous OP treatment. A sustained decrease in BP and concurrent limitation of movement, a reduction of days in bed, improvement of mobility and increase in the scale on self-reported QoL were observed 18 months after completion of treatment with TPTD. These findings should be interpreted in the context of a noncontrolled observational study. CONCLUSIONS An 18-month course of TPTD appears to have a beneficial effect on BP, mobility and QoL that is sustained up to 18 months after completion of treatment. [ABSTRACT FROM AUTHOR]

This predefined analysis of the European Forsteo Observational Study (EFOS) aimed to describe clinical fracture incidence, back pain, and health-related quality of life (HRQoL) during 18 months of teriparatide treatment and 18 months post-teriparatide in the subgroup of 589 postmenopausal women with osteoporosis aged ≥75 years. Data on clinical fractures, back pain (visual analogue scale, VAS), and HRQoL (EQ-5D) were collected over 36 months. Fracture data were summarized in 6-month intervals and analyzed using logistic regression with repeated measures. A repeated-measures model analyzed changes from baseline in back pain VAS and EQ-VAS. During the 36-month observation period, 87 (14.8 %) women aged ≥75 years sustained a total of 111 new fractures: 37 (33.3 %) vertebral fractures and 74 (66.7 %) nonvertebral fractures. Adjusted odds of fracture was decreased by 80 % in the 30 to <36-month interval compared with the first 6-month interval (P < 0.009). Although the older subgroup had higher back pain scores and poorer HRQoL at baseline than the younger subgroup, both age groups showed significant reductions in back pain and improvements in HRQoL postbaseline. In conclusion, women aged ≥75 years with severe postmenopausal osteoporosis treated with teriparatide in normal clinical practice showed a reduced clinical fracture incidence by 30 months compared with baseline. An improvement in HRQoL and, possibly, an early and significant reduction in back pain were also observed, which lasted for at least 18 months after teriparatide discontinuation when patients were taking other osteoporosis medication. The results should be interpreted in the context of an uncontrolled observational study. [ABSTRACT FROM AUTHOR]

Objectives: To describe fracture rates, back pain, and health-related quality of life (HRQoL) in postmenopausal women with osteoporosis and prior bisphosphonate therapy, treated with teriparatide for up to 18 months and followed up for a further 18 months. Design: Prospective, multinational, and observational study. Methods: Data on prior bisphosphonate use, clinical fractures, back pain visual analog scale (VAS), and HRQoL (EQ-5D) were collected over 36 months. Fracture data were summarized in 6-month intervals and analyzed using logistic regression with repeated measures. Changes from baseline in back pain VAS and EQ-VAS were analyzed using a repeated measures model. Results: Of the 1581 enrolled patients with follow-up data, 1161 (73.4%) had a history of prior bisphosphonate use (median duration: 36 months). Of them, 169 (14.6%) sustained ≥1 fracture during 36-month follow-up. Adjusted odds of fracture were significantly decreased at each 6-month interval compared with the first 6 months of teriparatide treatment: 37% decrease in the 12 to <18 months period during teriparatide treatment (P=0.03) and a 76% decrease in the 12- to 18-month period after teriparatide was discontinued (P<0.001). Significant reductions in back pain and improvement in HRQoL were observed. Conclusions: Postmenopausal women with severe osteoporosis previously treated with bisphosphonates had a significant reduction in the incidence of fractures compared with the first 6 months of therapy, a reduction in back pain and an improvement in HRQoL during up to 18 months of teriparatide treatment. These outcomes were still evident for at least 18 months after teriparatide was discontinued. The results should be interpreted in the context of an uncontrolled, observational study in a routine clinical setting. [ABSTRACT FROM AUTHOR]

Objective. To evaluate fracture incidence, effects on health-related quality of life(QoL), back pain (BP) occurrence and treatment compliance in Greek post-menopausal osteoporotic women treated with teriparatide (TPTD) for up to 18 months, in a naturalistic setting. Methods. 301 patients provided baseline information on demographic characteristics, fracture history, osteoporosis-related medication and risk factors. During treatment, QoL and BP severity were evaluated. Results. Mean (SD) age was 69.5 (±8.5) years. Fracture history was reported by 92.5% of patients. Incidence of fractures (per 10,000 patients/years) ranged from 402 during 0-6 months of treatment, to 346 during 12-18 months. All 5 dimensions of QoL showed improvement. At baseline and 18 months, BP was reported by 93.2% and 64.2% of patients, respectively. BP and limitation of activities were quantified as moderate or severe by 89.9% and 62.3% of patients at baseline versus 32.4% and 14.8% at 18 months. Patients on treatment at 6, 12, 17, and 18 months were 92.6%, 88.3%, 79.6%, and 36.5%, respectively. Conclusions. In the Greek EFOS study cohort, patients prescribed TPTD were severely osteoporotic, with considerable health-related problems. Significant improvements in QoL and BP together with low fracture rates and high compliance have been recorded during treatment. [ABSTRACT FROM AUTHOR]

An efficient modification of singular value decomposition (SVD) is proposed in this paper aiming at denoising and more importantly at quantifying more accurately the statistically independent spectra of metabolite sources in magnetic resonance spectroscopy (MRS). Although SVD is known in MRS applications and several efficient algorithms exist for estimating SVD summation terms in which the raw MRS data are analyzed, however, it would be more beneficial for such an analysis if techniques with the ability to estimate statistically independent spectra could be employed. SVD is known to separate signal and noise subspaces but it assumes orthogonal properties for the components comprising signal subspace, which is not always the case, and might impose heavy constraints for the MRS case. A much more relaxing constraint would be to assume statistically independent components. Therefore, a modification of the main methodology incorporating techniques for calculating the assumed statistically independent spectra is proposed by applying SVD on the MRS spectrogram through application of the short time Fourier transform (STFT). This approach is based on combining SVD on STFT spectrogram followed by an iterative application of independent component analysis (ICA). Moreover, it is shown that the proposed methodology combined with a regression analysis would lead to improved quantification of the MRS signals. An experimental study based on synthetic MRS signals has been conducted to evaluate the herein proposed methodologies. The results obtained have been discussed and it is shown to be quite promising. [ABSTRACT FROM AUTHOR]

A novel approach is presented in this paper for improving anisotropic diffusion PDE models, based on the Perona-Malik equation. A solution is proposed from an engineering perspective to adaptively estimate the parameters of the regularizing function in this equation. The goal of such a new adaptive diffusion scheme is to better preserve edges when the anisotropic diffusion PDE models are applied to image enhancement tasks. The proposed adaptive parameter estimation in the anisotropic diffusion PDE model involves self-organizing maps and Bayesian inference to define edge probabilities accurately. The proposed modifications attempt to capture not only simple edges but also difficult textural edges and incorporate their probability in the anisotropic diffusion model. In the context of the application of PDE models to image processing such adaptive schemes are closely related to the discrete image representation problem and the investigation of more suitable discretization algorithms using constraints derived from image processing theory. The proposed adaptive anisotropic diffusion model illustrates these concepts when it is numerically approximated by various discretization schemes in a database of magnetic resonance images (MRI), where it is shown to be efficient in image filtering and restoration applications. [ABSTRACT FROM AUTHOR]

Objective: The European Forsteo Observational Study (EFOS) study was primarily designed to assess fracture incidence, degree of pain, health-related quality of life (HRQoL) and compliance in women prescribed teriparatide in a community setting. This report describes the design of the study and characteristics of the patients at entry.Methods: At entry, 1645 postmenopausal women with a diagnosis of osteoporosis and about to initiate teriparatide treatment were enrolled in eight European countries. Baseline data were collected on demographic characteristics, medical and osteoporosis history, disease status, prior use of medications and HRQoL.Results: The mean (standard deviation [SD]) age of patients was 71.5 (8.4) years, lumbar spine bone mineral density (BMD) T-score was -3.3 (1.2), the mean number of previous fractures reported after 40 years of age was 2.9 (2.0), 70% had two or more vertebral deformities and 91.7% were pre-treated with bisphosphonates. HRQoL, evaluated by the health state value (HSV) (median: 0.59, Q1; Q3: 0.08; 0.71) and visual analogue scale (VAS) (median 50.0, Q1; Q3: 35.0; 69.0) status of the European quality of life questionnaire (EQ-5D) was poor. Extreme problems were reported by 31% of patients for the pain/discomfort dimension, mobility was limited in 69% and anxiety/depression was reported by 57% of patients. Chronic or intermittent back pain was reported by 91% of patients, which occurred every day or almost every day within the last month in 66% of patients.Conclusions: The post-menopausal women prescribed teriparatide were severely osteoporotic, with a high fracture risk and poor HRQoL, despite previous therapy for osteoporosis. Moderate to severe back pain was very common. [ABSTRACT FROM AUTHOR]

An efficient algorithm for the computation of the orthogonal Fourier–Mellin moments (OFMMs) is presented. The proposed method computes the fractional parts of the orthogonal polynomials, which consist of fractional terms, recursively, by eliminating the number of factorial calculations. The recursive computation of the fractional terms makes the overall computation of the OFMMs a very fast procedure in comparison with the conventional direct method. Actually, the computational complexity of the proposed method is linear O(p) in multiplications, with p being the moment order, while the corresponding complexity of the direct method is O(p2). Moreover, this recursive algorithm has better numerical behaviour, as it arrives at an overflow situation much later than the original one and does not introduce any finite precision errors. These are the two major advantages of the algorithm introduced in the current work, establishing the computation of the OFMMs to a very high order as a quite easy and achievable task. Appropriate simulations on images of different sizes justify the superiority of the proposed algorithm over the conventional algorithm currently used. [ABSTRACT FROM AUTHOR]

A novel approach for spam e-mail filtering is herein considered based on information theoretic extraction of higher order features and the committee machines neural network models. An extensive experimental study is organized, the most extensive so far in the literature, based on widely accepted benchmarking e-mail data sets, comparing the proposed methodology with the Naïve Bayes spam filter as well as with the Boosting tree methodology, the linear models-based classification (classification via regression) and the nonlinear models-based classification using simple neural network models, including Multilayer Perceptrons. Moreover, several feature extraction approaches based on information theory are evaluated, comparing mainly the proposed higher order feature extraction methodology with information theoretic extraction of single features. It is shown that the former outperforms the latter and, moreover, that the proposed information theoretic Boolean features present a remarkably high spam categorization performance compared to that of their analog counterparts. Finally, it is shown that the committee machines mail categorization performance compares very favorably to the other rival methods' performance, including the Bayes spam filter which is the most widely used approach in the e-mail services market. [ABSTRACT FROM AUTHOR]

While cloud computing infrastructures proliferates in nowadays computing and communications technology there are few reports investigating models for their security. In this paper, new efficient models are developed and evaluated for analyzing the security-related behavior of cloud computing architectures and networks comprising complex interconnected communication systems adapted towards a generalized analysis. These cloud related models, based on Markov processes, allow calculation of critical security factors for the cloud infrastructure, related to intrusion detection, of such interconnected and distributed systems components and the evaluation of the associated security mechanisms. Although, at this step an architecture of at least three interconnected systems is analyzed, the systematic model introduced allows for a generalized model of N interconnected systems in a cloud architecture under reasonable assumptions. We herein show the principles of such an analysis. Security parameters calculation and Security mechanisms evaluation may support the risk analysis and the decision making process in resolving the trade-offs between security and quality of service characteristics corresponding to the complex interconnected computing and communication systems.