Abstract
This work presents a fiber cavity ring down (CRD) configuration for the measurement of strain. An optical time-domain reflectometer (OTDR) was used to send impulses down into the fiber loop cavity, inside of which a chirped fiber Bragg grating was placed to act as a strain sensing element. This technique could provide strain results with both conventional CRD-based configuration and the OTDR. The CRD configuration provided a linear response to strain applied in the range 0-2000 epsilon, and a sensitivity of 1.34 ns/epsilon was obtained. For the same operation range, the OTDR interrogation allowed obtaining a periodic behavior due to fiber Bragg grating scanning of the wavelength peaks of the multimode laser source while increasing strain. It is shown that the OTDR interrogation method provide a ring-down time response of about 8 s which is a great improvement when compared to the conventional CRD configuration (23 s). (c) 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1442-1444, 2015

Abstract
This article estimates the efficiency of the 40 retail stores of a prestigious clothing company that operates in the Portuguese fast-fashion retailing market. The study compares the performance among the stores and provides insights into ways of improving performance in the retail clothing industry. A two-stage approach is used in this article. In a first stage, Data Envelopment Analysis (DEA) techniques are used to evaluate the performance of each store and to rank the stores. The input-oriented model was used to assess the summer and winter collections between 2010 and 2013. The results show that the total technical efficiency of the company decreases over time Except for the year 2013, over 90% of the stores show increasing returns to scale during 88% of the period analyzed. The company faces a clear problem of productivity in its retailing operations. This deficiency seems to be intrinsic to the firm as it involves more than 60% of the stores. In a second stage, a quantile regression technique was used. This showed primarily that for the lowest quantiles of the efficiency score conditional distribution the coefficients on experience are very low, even close to zero, which suggests that the efforts taken by the stores in terms of experience are barely recognized by consumers in this fast-fashion retailing chain.

Abstract
Objective. To investigate the role of endothelial dysfunction and angiogenesis vascular biomarkers as risk factors and their predictive value for digital ulcers in systemic sclerosis patients. Methods. Endothelin-1 (ET-1), asymmetric dimethylarginine (ADMA), vascular endothelial growth factor (VEGF), endostatin and endoglin were measured in an observational prospective cohort of 77 SSc patients. The primary outcome was the occurrence of one or more new ischaemic digital ulcers during a planned 3-year follow-up. Results. After the 3-year follow-up, 40 patients developed new digital ulcers. Logistic regression confirmed VEGF (HR 1.128,95% CI 1.010-1.260, p=0.033) and ADMA(HR 0.995, 95% CI 0.991-0.998, p=0.006) as independent predictors of new digital ulcers. Patients with serum levels of ET-1>11.9pmol/ml (p<0.001) and VEGF<422.47 pg/ml (p=0.028) had significantly more DU in the 3-year follow-up. Although not significant, a trend towards increased serum levels of endoglin>4.215ng/ml (p=0.053) was associated to a new DU episode. No predictive serum value was found for ADMA (p=0.075) and endostatin (p=0.130). Conclusions. Endothelial dysfunction and angiogenic vascular biomarkers have an important role in the underlying and in the progression of microvascular disease in systemic sclerosis. Increased serum levels of ET-1, ADMA and VEGF are strong predictors of severe microangiopathy complications, namely ischaemic digital ulcers.

Abstract
Rehabilitation processes follow, as a rule, intensive training programs, composed of repetitive and monotonous tasks for patients. The introduction of serious games in these processes can help in motivating patients, increasing their interest in the exercises to perform. These games should be set taking into account characteristics that are able to stimulate and train cognitive functions as well as features that require some kind of motor activity in order to stimulate and attract patients' attention. This article presents a literature review on serious games for cognitive rehabilitation and a set of characteristics that are considered important for serious game development in this area which include the use of natural and multimodal interfaces and a social dimension such as collaboration, competition and the concept of handicap.

Abstract
Data stream classification algorithms for nonstationary environments frequently assume the availability of class labels, instantly or with some lag after the classification. However, certain applications, mainly those related to sensors and robotics, involve high costs to obtain new labels during the classification phase. Such a scenario in which the actual labels of processed data are never available is called extreme verification latency. Extreme verification latency requires new classification methods capable of adapting to possible changes over time without external supervision. This paper presents a fast, simple, intuitive and accurate algorithm to classify nonstationary data streams in an extreme verification latency scenario, namely Stream Classification Algorithm Guided by Clustering - SCARGC. Our method consists of a clustering followed by a classification step applied repeatedly in a closed loop fashion. We show in several classification tasks evaluated in synthetic and real data that our method is faster and more accurate than the state-of-the-art.

Abstract
A domain-specific language (DSL) aims to support software development by offering abstractions to a particular domain. It is expected that DSLs improve the maintainability of artifacts otherwise produced with general-purpose languages. However, the maintainability of the DSL artifacts and, hence, their adoption in mainstream development, is largely dependent on the usability of the language itself. Unfortunately, it is often hard to identify their usability strengths and weaknesses early, as there is no guidance on how to objectively reveal them. Usability is a multi-faceted quality characteristic, which is challenging to quantify beforehand by DSL stakeholders. There is even less support on how to quantitatively evaluate the usability of DSLs used in maintenance tasks. In this context, this paper reports a study to compare the usability of textual DSLs under the perspective of software maintenance. A usability measurement framework was developed based on the cognitive dimensions of notations. The framework was evaluated both qualitatively and quantitatively using two DSLs in the context of two evolving object-oriented systems. The results suggested that the proposed metrics were useful: (1) to early identify DSL usability limitations, (2) to reveal specific DSL features favoring maintenance tasks, and (3) to successfully analyze eight critical DSL usability dimensions.