Risk assessment in open source systems

Adopting Open Source Software (OSS) components offers many advantages to organizations but also introduces risks related to the intrinsic fluidity of the OSS development projects. Choosing the right components is a critical decision, as it could contribute to the success of any adoption process. Making the right decision requires to evaluate the technical capabilities of the components and also related strategic aspects, including possible impacts on high level objectives. This can be achieved through a portfolio of risk assessment and mitigation methods. In this briefing we introduce the basic concepts related to OSS ecosystems and to risk representation and reasoning. We illustrate how risk management activities in OSS can benefit from the large amount of data available from OSS repositories and how they can be connected to business goals for strategic decision-making. The concepts are illustrated with a software platform developed in the context of the EU FP7 project RISCOSS.Peer ReviewedPostprint (author's final draft

Riesgo cardiovascular y metabolismo de la glucosa: acuerdos y discrepancias entre las clasificaciones OMS-85 y ADA-97

ObjetivoConocer las diferencias entre el riesgo coronario de los sujetos con glucemia basal alterada (GBA), intolerancia oral a la glucosa (ITG) y diabetes mellitus tipo 2 según las clasificaciones diagnósticas de la OMS-85 y ADA-97 en una población adulta con un riesgo alto de presentar diabetes mellitus.DiseñoEstudio descriptivo, transversal, multicéntrico.EmplazamientoAtención primaria, 7 centros de salud.PacientesUn total de 970 sujetos considerados población de riesgo para diabetes mellitus tipo 2.MedicionesSe clasificaron los sujetos según los criterios OMS-85 (normales, ITG, diabetes) y según la ADA-97 (normales, GBA y diabetes). Se recogieron las siguientes variables: edad, sexo, consumo de tabaco, índice de masa corporal, tensión arterial sistólica, tensión arterial diastólica, glucemia basal, glucemia a las 2 horas de la PTOG, HbA1c, microalbuminuria, colesterol total, cHDL, cLDL, triglicéridos y se estimó el cálculo del riesgo coronario mediante la tabla de Wilson et al de 1998, basada en el estudio Framingham.ResultadosSe evaluó a 970 sujetos con una edad media de 58,6 ± 12,4 años, 453 varones (46,7%) y 517 mujeres (53,3%). En el análisis de la presencia de factores de riesgo cardiovascular se observa que éstos son menos frecuentes en los sujetos normales y que su prevalencia es más elevada en los diabéticos (OMS y ADA). No existen diferencias significativas entre el riesgo coronario y los diversos factores de riesgo cuando se analizan grupos homónimos OMS–ADA (normales, ITG-GBA o diabéticos). Según la clasificación de la OMS-85, el riesgo coronario en los distintos tipos de alteraciones del metabolismo de la glucosa fue un 11,3% en sujetos normales, un 14% en ITG y un 27,3% en diabéticos, y según la ADA-97 un 11,4% en sujetos normales, un 15,7% en GBA y un 29,5% en diabéticos.ConclusionesA mayor grado de patología hidrocarbonada, mayor coexistencia de factores de riesgo y mayor estimación del riesgo coronario. No hay diferencias importantes entre los estadios de las clasificaciones OMS y ADA ni en la presencia de factores de riesgo cardiovascular ni en relación al riesgo coronario.AimTo identify the differences between coronary heart disease risk in patients with altered basal glucemia (ABG), oral glucose intolerance (OGI) and type II diabetes mellitus according to the WHO-85 and ADA-97 diagnostic classifications, in an adult population at high risk for diabetes mellitus.DesignDescriptive, cross-sectional, multicenter study.SettingSeven primary health care centers in Spain.Patient970 persons considered the population at risk for type II diabetes mellitus.MeasuresParticipants were classified according to the criteria of the WHO-85 (normal, OGI, diabetes) and the ADA-97 system (normal, ABG, diabetes). The following variables were recorded: age, sex, smoking habit, body mass index, systolic blood pressure, diastolic blood pressure, basal glucemia, glucemia 2 h after an oral glucose tolerance test, HbA1c, microalbmuniuria, total cholesterol, HDL, LDL and triglycerides. Coronary heart disease risk was calculated with the 1998 table developed by Wilson et al. on the basis of the Framingham study.ResultsA total of 970 participants were studied. Mean age was 58.6 #+ 12.4 years; 453 were men (46.7%) and 517 were women (53.3%). Our analysis showed that cardiovascular disease risk factors were less frequent in normal subjects, and that their prevalence was higher in persons with diabetes (according to both WHO and ADA classifications). There were no significant differences in coronary heart disease risk or different risk factors between analogous groups in the two classification systems (normal, OGI/ABG or diabetes). Coronary heart disease risk in persons with different types of alterations in glucose metabolism was 11.3% in normal subjects, 14% in persons with OGI and 27.3% in persons with diabetes according to the WHO-85 system, and 11.4% in normal subjects, 15.7% in persons with ABG and 29.5% in persons with diabetes according to the ADA-97 system.ConclusionsThe greater the alteration in carbohydrate metabolism, the greater the coexistence of risk factors and the estimated risk of coronary heart disease. There were no significant differences in the presence of cardiovascular risk factors, or in the relationship between carbohydrate metabolism and coronary heart disease risk, between analogous stages identified with one classification system or the other

The influence of the C+N+O abundances on the determination of the relative ages of Globular Clusters: the case of NGC 1851 and NGC 6121 (M4)

The color magnitude diagram (CMD) of NGC 1851 presents two subgiant branches (SGB), probably due the presence of two populations differing in total CNO content. We test the idea that a difference in total CNO may simulate an age difference when comparing the CMD of clusters to derive relative ages. We compare NGC 1851 with NGC 6121 (M4), a cluster of very similar [Fe/H]. We find that, with a suitable shift of the CMDs that brings the two red horizontal branches at the same magnitude level, the unevolved main sequence and red giant branch match, but the SGB of NGC 6121 and its red giant branch "bump" are fainter than in NGC 1851. In particular, the SGB of NGC 6121 is even slightly fainter than the the faint SGB in NGC 1851. Both these features can be explained if the total CNO in NGC 6121 is larger than that in NGC 1851, even if the two clusters are coeval. We conclude by warning that different initial C+N+O abundances between two clusters, otherwise similar in metallicity and age, may lead to differences in the turnoff morphology that can be easily attributed to an age difference.Comment: accepted for publication in MNRA

Data-driven elicitation of quality requirements in agile companies

Quality Requirements (QRs) are a key artifact to ensure the quality and success of a software system. Despite its importance, QRs have not reached the same degree of attention as its functional counterparts, especially in the context of trending software development methodologies like Agile Software Development (ASD). Moreover, crucial information that can be obtained from data sources of a project under development (e.g. JIRA, github,…) are not fully exploited, or even neglected, in QR elicitation activities. In this work, we present a data-driven approach to semi-automatically generate and document QRs in the context of ASD. We define an architecture focusing on the process and the artefacts involved. We validate and iterate on such architecture by conducting workshops in four companies of different size and profile. Finally, we present the implementation of such architecture, considering the feedback and outcomes of the conducted workshops.Peer ReviewedPostprint (author's final draft

Quantification of Mitral Regurgitation With MR Phase-Velocity Mapping Using a Control Volume Method

Reliable diagnosis and quantification of mitral regurgitation are important for patient management and for optimizing the time for surgery. Previous methods have often provided suboptimal results. The aim of this in vitro study was to evaluate MR phase-velocity mapping in quantifying the mitral regurgitant volume (MRV) using a control volume (CV) method. A number of contiguous slices were acquired with all three velocity components measured. A CV was then selected, encompassing the regurgitant orifice. Mass conservation dictates that the net inflow into the CV should be equal to the regurgitant flow. Results showed that a CV, the boundary voxels of which excluded the region of flow acceleration and aliasing at the orifice, provided accurate measurements of the regurgitant flow. A smaller CV provided erroneous results because of flow acceleration and velocity aliasing close to the orifice. A large CV generally provided inaccurate results because of reduced velocity sensitivity far from the orifice. Aortic outflow, orifice shape, and valve geometry did not affect the accuracy of the CV measurements. The CV method is a promising approach to the problem of quantification of the MRV

The GALANTE Photometric System

This paper describes the characterization of the GALANTE photometric system, a seven intermediate- and narrow-band filter system with a wavelength coverage from 3000 $\r{A}$ to 9000 $\r{A}$ . We describe the photometric system presenting the full sensitivity curve as a product of the filter sensitivity, CCD, telescope mirror, and atmospheric transmission curves, as well as some first- and second-order moments of this sensitivity function. The GALANTE photometric system is composed of four filters from the J-PLUS photometric system, a twelve broad-to-narrow filter system, and three exclusive filters, specifically designed to measure the physical parameters of stars such as effective temperature $T_{\rm eff}$, $\log(g)$, metallicity, colour excess $E(4405-5495)$, and extinction type $R_{5495}$. Two libraries, the Next Generation Spectral Library (NGSL) and the one presented in Ma\'iz Apell\'aniz & Weiler (2018), have been used to determine the transformation equations between the Sloan Digital Sky Survey ($\textit{SDSS}$) $\textit{ugriz}$ photometry and the GALANTE photometric system. We will use this transformation to calibrate the zero points of GALANTE images. To this end, a preliminary photometric calibration of GALANTE has been made based on two different $\textit{griz}$ libraries ($\textit{SDSS}$ DR12 and ATLAS All-Sky Stellar Reference Catalog, hereinafter $\textit{RefCat2}$). A comparison between both zero points is performed leading us to the choice of $\textit{RefCat2}$ as the base catalogue for this calibration, and applied to a field in the Cyg OB2 association.Comment: Accepted in MNRA

Slice Location Dependence of Aortic Regurgitation Measurements with MR Phase Velocity Mapping

Although several methods have been used clinically to assess aortic regurgitation (AR), there is no “gold standard” for regurgitant volume measurement. Magnetic resonance phase velocity mapping (PVM) can be used for noninvasive blood flow measurements. To evaluate the accuracy of PVM in quantifying AR with a single imaging slice in the ascending aorta, in vitro experiments were performed by using a compliant aortic model. Attention was focused on determining the slice location that provided the best results. The most accurate measurements were taken between the aortic valve annulus and the coronary ostia where the measured (Y) and actual (X) flow rate had close agreement (Y = 0.954 × + 0.126, r2 = 0.995, standard deviation of error = 0.139 L/min). Beyond the coronary ostia, coronary flow and aortic compliance negatively affected the accuracy of the measurements. In vivo measurements taken on patients with AR showed the same tendency with the in vitro results. In making decisions regarding patient treatment, diagnostic accuracy is very important. The results from this study suggest that higher accuracy is achieved by placing the slice between the aortic valve and the coronary ostia and that this is the region where attention should be focused for further clinical investigation

Evaluation of the Precision of Magnetic Resonance Phase Velocity Mapping for Blood Flow Measurements

Evaluating the in vivo accuracy of magnetic resonance phase velocity mapping (PVM) is not straightforward because of the absence of a validated clinical flow quantification technique. The aim of this study was to evaluate PVM by investigating its precision, both in vitro and in vivo, in a 1.5 Tesla scanner. In the former case, steady and pulsatile flow experiments were conducted using an aortic model under a variety of flow conditions (steady: 0.1–5.5 L/min; pulsatile: 10–75 mL/cycle). In the latter case, PVM measurements were taken in the ascending aorta of ten subjects, seven of which had aortic regurgitation. Each velocity measurement was taken twice, with the slice perpendicular to the long axis of the aorta. Comparison between the measured and true flow rates and volumes confirmed the high accuracy of PVM in measuring flow in vitro (p \u3e 0.85). The in vitro precision of PVM was found to be very high (steady: y = 1.00x + 0.02, r = 0.999; pulsatile: y = 0.98x + 0.72, r = 0.997; x: measurement #1, y: measurement #2) and this was confirmed by Bland-Altman analysis. Of great clinical significance was the high level of the in vivo precision (y = 1.01x − 0.04, r = 0.993), confirmed statistically (p = 1.00). In conclusion, PVM provides repeatable blood flow measurements. The high in vitro accuracy and precision, combined with the high in vivo precision, are key factors for the establishment of PVM as the “gold-standard” to quantify blood flow