Can we avoid high coupling?

It is considered good software design practice to organize source code into modules and to favour within-module connections (cohesion) over between-module connections (coupling), leading to the oft-repeated maxim "low coupling/high cohesion". Prior research into network theory and its application to software systems has found evidence that many important properties in real software systems exhibit approximately scale-free structure, including coupling; researchers have claimed that such scale-free structures are ubiquitous. This implies that high coupling must be unavoidable, statistically speaking, apparently contradicting standard ideas about software structure. We present a model that leads to the simple predictions that approximately scale-free structures ought to arise both for between-module connectivity and overall connectivity, and not as the result of poor design or optimization shortcuts. These predictions are borne out by our large-scale empirical study. Hence we conclude that high coupling is not avoidable--and that this is in fact quite reasonable

MASTER: The Mobile Astronomical System of Telescope-Robots

We present the first russian robot-telescope designed to make prompt observations of gamma-ray bursts (http://observ.pereplet.ru). The telescopes are near Moscow. The system of telescopes with prompt pointing rates connects to the internet. The main parameters are the following: Richter-Slefogt system telescope (355 mm, f/d=2.4); Richter-Slefogt system telescope (200mm, f/d=2.4); Flugge system telescope (280mm, f/d=2.5); TV-camera with 20x40 degree objective; Two CCD cameras (Pictor 416); One CCD Apogee Camera AP16E. The type of mount is German with 8 grad/sec slew rate. MASTER images stars down to 19 magnitude in a 1 min exposure covering 6 square degrees.Comment: 3 pages, 2 figure

Risk assessment of men, underwented myocardial infarction in young age

A retrospective analysis of 96 patient’s cards with myocardial infarction in age younger then 40 years showed, that in this sampling such risk factors as smoking, overweight, arterial hypertension and dyslipidemia are of maximum value.Ретроспективный анализ 96 историй болезни пациентов, перенесших инфаркт миокарда в возрасте до 40 лет, показал, что в этой возрастной группе наибольшее значение в развитии заболевания имеют такие факторы риска, как курение, избыточная масса тела, артериальная гипертония и дислипидемия

Sindarin: A Versatile Scripting API for the Pharo Debugger

International audienceDebugging is one of the most important and time consuming activities in software maintenance, yet mainstream debuggers are not well-adapted to several debugging scenarios. This has led to the research of new techniques covering specific families of complex bugs. Notably, recent research proposes to empower developers with scripting DSLs, plugin-based and moldable debuggers. However, these solutions are tailored to specific use-cases, or too costly for one-time-use scenarios. In this paper we argue that exposing a debugging scripting interface in mainstream debuggers helps in solving many challenging debugging scenarios. For this purpose, we present Sindarin, a scripting API that eases the expression and automation of different strategies developers pursue during their debugging sessions. Sindarin provides a GDB-like API, augmented with AST-bytecode-source code mappings and object-centric capabilities. To demonstrate the versatility of Sindarin, we reproduce several advanced breakpoints and non-trivial debugging mechanisms from the literature

Restructuring of colloidal aggregates in shear flow: Coupling interparticle contact models with Stokesian dynamics

A method to couple interparticle contact models with Stokesian dynamics (SD) is introduced to simulate colloidal aggregates under flow conditions. The contact model mimics both the elastic and plastic behavior of the cohesive connections between particles within clusters. Owing to this, clusters can maintain their structures under low stress while restructuring or even breakage may occur under sufficiently high stress conditions. SD is an efficient method to deal with the long-ranged and many-body nature of hydrodynamic interactions for low Reynolds number flows. By using such a coupled model, the restructuring of colloidal aggregates under stepwise increasing shear flows was studied. Irreversible compaction occurs due to the increase of hydrodynamic stress on clusters. Results show that the greater part of the fractal clusters are compacted to rod-shaped packed structures, while the others show isotropic compaction.Comment: A simulation movie be found at http://www-levich.engr.ccny.cuny.edu/~seto/sites/colloidal_aggregates_shearflow.htm

A flare in the optical spotted in the changing-look Seyfert NGC 3516

We present observations from the short-term intensive optical campaign (from Sep2019 to Jan2020) of the changing-look Seyfert NGC 3516. This active galactic nucleus is known to have strong optical variability and has changed its type in the past. It has been in the low-activity state in the optical since 2013, with some rebrightening from the end of 2015 to the beginning of 2016, after which it remained dormant. We aim to study the photometric and spectral variability of NGC 3516 from the new observations in U- and B-bands and examine the profiles of the optical broad emission lines in order to demonstrate that this object may be entering a new state of activity. NGC 3516 has been monitored intensively for the past 4 months with an automated telescope in U and B filters, enabling accurate photometry of 0.01 precision. Spectral observations were triggered when an increase in brightness was spotted. We support our analysis of past-episodes of violent variability with the UV and X-ray long-term light curves constructed from the archival Swift data. An increase of the photometric magnitude is seen in both U and B filters to a maximum amplitude of 0.25mag and 0.1 mag, respectively. During the flare, we observe stronger forbidden high-ionization iron lines than reported before, as well as the complex broad Ha and Hb lines. This is especially seen in Ha which appears to be double-peaked. It seems that a very broad component of ~10,000 km/s in width in the Balmer lines is appearing. The trends in the optical, UV, and X-ray light curves are similar, with the amplitudes of variability being significantly larger in the case of UV and X-ray bands. The increase of the continuum emission, the variability of the coronal lines, and the very broad component in the Balmer lines may indicate that the AGN of NGC 3516 is finally leaving the low-activity state in which it has been for the last ~3 years.Comment: 7 pages, 6 figures, accepted in A&A (corrected after receiving comments from the language editor

Efficacy of a Relaxation Scenario in Virtual Reality for the Comorbid Symptoms of Anxiety and Asthenia in a General Hospital Setting: A Pilot Comparative Randomized Open-Label Study

BACKGROUND: Patients in general hospitals often display concomitant signs of mental maladjustment: low mood, anxiety, apathy, asthenia, all of which can have a negative impact on the course of the underlying disease and the recovery process. One of the non-pharmacological approaches that has gained wider acceptance in medical practice in recent years is the use of procedures based on virtual reality. AIM: Assess the efficacy of the new domestic, virtual reality application Flow as relates to symptoms of anxiety and asthenia in patients undergoing inpatient treatment. METHODS: The study was open-label and had a comparison group; the patients were assigned to the experimental or control group using a randomization table. The patients were assessed using the Spielberger State Anxiety Inventory; the Fatigue Symptom Rating Scale; the Well-being, Activity, Mood questionnaire; the Depression Anxiety Stress Scale; and the Clinical Global Impression Scale. Physical parameters were measured before and after each virtual reality session. The obtained data were statistically processed. RESULTS: The study involved 60 patients. In 40 patients, the treatment program included a course of five daily relaxation sessions in virtual reality; the control group consisted of 20 patients, who were treated in accordance with the usual practice of the institution. The addition of virtual reality sessions to the standard treatment course yielded significant advantage in terms of affective symptoms reduction in patients both after a single session and as a result of undergoing the full course, and several days after its completion. The patients in the experimental group also showed a significant decrease in blood pressure after the sessions, and this was most pronounced in individuals who initially had elevated and high blood pressure. CONCLUSION: The use of relaxation program courses in the virtual reality application Flow is an effective and promising means of non-pharmacological care for non-psychiatric inpatients showing symptoms of anxiety, apathy, depressive mood, as well as hypertension

Assesment of the student’s knowledge on medical and organizational aspects of HIV prevention

The article is devoted to a comparative analysis of data of sociological study to assess the level of awareness and special knowledge of medical University students on the main medical and organizational issues of HIV prevention. A questionnaire survey of 1-6 courses students, 752 respondents was conducted. Respondents demonstrated high level of awareness of the main routes of HIV transmission, which indicates the effectiveness of regional information campaigns. At the same time, there is insufficient knowledge of modern legal issues and clinical and diagnostic characteristics of HIV infection. The rates of correct answers are significantly higher for senior students. It is necessary to update educational modules in clinical and medical-preventive disciplines in order to achieve higher level of knowledge of future doctors on modern requirements for preventing the spread of HIV infectionСтатья посвящена сравнительному анализу данных социологического исследования по оценке уровня информированности и специальных знаний по основным медико-организационным вопросам профилактики ВИЧ-инфекции у студентов медицинского университета. Проведено анкетирование студентов 1-6 курсов, всего опрошено 752 чел. Респонденты демонстрируют высокий уровень информированности об основных путях передачи ВИЧ-инфекции, что указывает на результативность проводимых в регионе информационных кампаний. Наряду с этим, установлен недостаточный уровень специальных знаний по современным правовым вопросам профилактики и клинико-диагностическим характеристикам ВИЧ-инфекции. Показатели правильных ответов достоверно выше у студентов старших курсов. Необходимо актуализировать образовательные модули в преподавании клинических и медико-профилактических дисциплин для достижения более высокого уровня знаний будущих врачей по современным требованиям профилактики и противодействия распространению ВИЧ-инфекци