Towards an MDA-based development methodology for distributed applications

This paper proposes a development methodology for distributed applications based on the principles and concepts of the Model-Driven Architecture (MDA). The paper identifies phases and activities of an MDA-based development trajectory, and defines the roles and products of each activity in accordance with the Software Process Engineering Metamodel (SPEM). The development methodology presented in this paper is being developed and applied in the European 5th Framework project MODA-TEL, which aims at assessing the applicability and potential of MDA in the context of telecom services and applications. This paper also discusses the application of the proposed methodology on a typical telecom service case study. The paper claims that the proposed methodology is general enough to be applicable to distributed applications in other domains as well

The massive star population of the Virgo Cluster galaxy NGC 4535

We analyzed the massive star population of the Virgo Cluster galaxy NGC 4535 using archival Hubble Space Telescope Wide Field Planetary Camera 2 images in filters F555W and F814W, equivalent to Johnson V and Kron-Cousins I. We performed high precision point spread function fitting photometry of 24353 sources including 3762 candidate blue supergiants, 841 candidate yellow supergiants and 370 candidate red supergiants. We estimated the ratio of blue to red supergiants as a decreasing function of galactocentric radius. Using Modules for Experiments in Stellar Astrophysics isochrones at solar metallicity, we defined the luminosity function and estimated the star formation history of the galaxy over the last 60 Myrs. We conducted a variability search in the V and I filters using three variability indexes: the median absolute deviation, the interquartile range and the inverse von-Neumann ratio. This analysis yielded 120 new variable candidates with absolute magnitudes ranging from M$_{V}$ = $-$4 to $-$11 mag. We used the MESA evolutionary tracks at solar metallicity, to classify the variables based on their absolute magnitude and their position on the color-magnitude diagram. Among the new candidate variable sources are eight candidate variable red supergiants, three candidate variable yellow supergiants and one candidate luminous blue variable, which we suggest for follow-up observations.Comment: Accepted by A&A, 7 pages, 7 Tables, 53 figure

Comparative performance of selected variability detection techniques in photometric time series

Photometric measurements are prone to systematic errors presenting a challenge to low-amplitude variability detection. In search for a general-purpose variability detection technique able to recover a broad range of variability types including currently unknown ones, we test 18 statistical characteristics quantifying scatter and/or correlation between brightness measurements. We compare their performance in identifying variable objects in seven time series data sets obtained with telescopes ranging in size from a telephoto lens to 1m-class and probing variability on time-scales from minutes to decades. The test data sets together include lightcurves of 127539 objects, among them 1251 variable stars of various types and represent a range of observing conditions often found in ground-based variability surveys. The real data are complemented by simulations. We propose a combination of two indices that together recover a broad range of variability types from photometric data characterized by a wide variety of sampling patterns, photometric accuracies, and percentages of outlier measurements. The first index is the interquartile range (IQR) of magnitude measurements, sensitive to variability irrespective of a time-scale and resistant to outliers. It can be complemented by the ratio of the lightcurve variance to the mean square successive difference, 1/h, which is efficient in detecting variability on time-scales longer than the typical time interval between observations. Variable objects have larger 1/h and/or IQR values than non-variable objects of similar brightness. Another approach to variability detection is to combine many variability indices using principal component analysis. We present 124 previously unknown variable stars found in the test data.Comment: 29 pages, 8 figures, 7 tables; accepted to MNRAS; for additional plots, see http://scan.sai.msu.ru/~kirx/var_idx_paper

Influence of physician empathy on the outcome of botulinum toxin treatment for upper limb spasticity in patients with chronic stroke: A cohort study.

To examine the relationship between patient-rated physician empathy and outcome of botulinum toxin treatment for post-stroke upper limb spasticity.Cohort study.Twenty chronic stroke patients with upper limb spasticity.All patients received incobotulinumtoxinA injection in at least one muscle for each of the following patterns: flexed elbow, flexed wrist and clenched fist. Each treatment was performed by 1 of 5 physiatrists with equivalent clinical experience. Patient-rated physician empathy was quantified with the Consultation and Relational Empathy Measure immediately after botulinum toxin treatment. Patients were evaluated before and at 4 weeks after botulinum toxin treatment by means of the following outcome measures: Modified Ashworth Scale; Wolf Motor Function Test; Disability Assessment Scale; Goal Attainment Scaling.Ordinal regression analysis showed a significant influence of patient-rated physician empathy (independent variable) on the outcome (dependent variables) of botulinum toxin treatment at 4 weeks after injection, as measured by Goal Attainment Scaling (p<0.001).These findings support the hypothesis that patient-rated physician empathy may influence the outcome of botulinum toxin treatment in chronic stroke patients with upper limb spasticity as measured by Goal Attainment Scaling