Efficiency of ETV diagrams as diagnostic tools for long-term period variations. II. Non-conservative mass transfer, and gravitational radiation

The credibility of an eclipse timing variation (ETV) diagram analysis is investigated for various manifestations of the mass transfer and gravitational radiation processes in binary systems. The monotonicity of the period variations and the morphology of the respective ETV diagrams are thoroughly explored in both the direct impact and the accretion disk mode of mass transfer, accompanied by different types of mass and angular momentum losses (through a hot-spot emission from the gainer and via the L2/L3 points). Mass transfer rates comparable to or greater than 10^{-8} M_sun/yr are measurable for typical noise levels of the ETV diagrams, regardless of whether the process is conservative. However, the presence of a transient disk around the more massive component defines a critical mass ratio q_cr ~ 0.83 above which the period turns out to decrease when still in the conservative regime, rendering the measurability of the anticipated variations a much more complicated task. The effects of gravitational radiation proved to be rather undetectable, except for systems with physical characteristics that only refer to cataclysmic variables. Unlike the hot-spot effects, the Lagrangian points L2 and L3 support very efficient routes of strong angular momentum loss. It is further shown that escape of mass via the L3 point - when the donor is the less massive component - safely provides critical mass ratios above which the period is expected to decrease, no matter how intense the process is.Comment: 13 pages, 6 figures, 10 tables, published in A&

THE ACCELEROMETRIC NETWORK OF THE INDES-MUSA PROJECT IN THE KALOCHORI AREA: CONFIGURATION, DOCUMENTATION AND PRELIMINARY DATA INTERPRETATION

Ένα δίκτυο επτά επιταχυνσιογράφων στην επιφάνεια του εδάφους και σε κατασκευές εγκαταστάθηκε πρόσφατα στην ευρύτερη περιοχή Καλοχωρίου, δυτικά της Θεσσαλονίκης, στο πλαίσιο του ερευνητικού έργου INDES-MUSA ως τμήμα πολυπαραμετρικού δικτύου καταγραφής της σεισμικής κίνησης και της εδαφικής υποχώρησης της περιοχής. Το δίκτυο περιλαμβάνει σταθμούς εγκατεστημένους στην επιφάνεια του εδάφους και στην κορυφή τυπικών κατασκευών εντός αστικών υποσυνόλων καθώς και ένα σταθμό ελευθέρου πεδίου. Όλοι οι σταθμοί έχουν τεκμηριωθεί καταλλήλως, λαμβάνοντας υπόψη τα ιδιαίτερα χαρακτηριστικά της κάθε εγκατάστασης καθώς και τα χαρακτηριστικά της εδαφικής δομής, όπως αυτά εκφράζονται από την κατανομή με το βάθος της ταχύτητας διάδοσης των διατμητικών κυμάτων σε κάθε θέση. Παρουσιάζονται καταγραφές του δικτύου επιταχυνσιογράφων από τριαντά εννιά σεισμούς και δίνεται η διαδικασία διόρθωσης που εφαρμόστηκε στις πρωτογενείς χρονοϊστορίες επιτάχυνσης κατά το στάδιο επεξεργασίας και αποθήκευσης των σημάτων. Τέλος, παρουσιάζονται προκαταρκτικές συγκρίσεις τιμών μέγιστης εδαφικής επιτάχυνσης μεταξύ σταθμών εντός οικιστικής ζώνης και ελευθέρου πεδίου καθώς και συγκρίσεις φασματικών λόγων οροφής κατασκευών και βάσης με σκοπό την προκαταρκτική εκτίμηση των θεμελιωδών δυναμικών χαρακτηριστικών των ενοργανωμένων κατασκευών. Τα παραπάνω δεδομένα καταγραφών και τεκμηρίωσης είναι διαθέσιμα μέσω της διαδικτυακής πλατφόρμας Web-GIS του έργου INDESMUSA. A network of seven accelerometric stations on both ground surface and structures has been recently installed, as part of a multi-sensor network for monitoring seismic motion and ground subsidence in the broader area of Kalochori, west of Thessaloniki in Northern Greece, within the INDES-MUSA project. This network includes ground installations within the urban area, structural stations on top of structures and a freefield station away from the building stock. The documentation of stations is presented including shear wave velocity profiles of the subsoil at each location. A set of thirtynine earthquakes recorded so far by the accelerometric network is reported, followed by data processing procedures performed in the acquired waveforms. Comparisons of the processed earthquake recordings are presented referring to (a) the urbanground and the free-field stations in terms of peak ground acceleration, indicating amplification trends of ground motion, and (b) the structural and the nearby urban ground stations by means of top-to-base ratios in the frequency domain, towards a preliminary identification of the fundamental vibrational characteristics of the instrumented structures. The processed acceleration data are available through the INDES-MUSA Web-GIS portal

A Search for Pulsating, Mass-Accreting Components in Algol-Type Eclipsing Binaries

We present a status report on the search for pulsations in primary componants of Algols systems (oEA stars). Analysis of 21 systems with A0-F2 spectral type primaries revealed pulsations in two systems suggesting that of the order of ten persent of Algols primaries in this range are actually pulsators

Assessing the knowledge of bronchial asthma among primary health care physicians in Crete: A pre- and post-test following an educational course

AIM: To assess the level of knowledge for bronchial asthma of the primary healthcare physicians serving a rural population on the island of Crete, both before and immediately after a one-day educational course. METHODS: Twenty-one primary health care physicians, randomly selected from a list of 14 Health Care Centres on the island of Crete were invited to participate in the study and attended an educational course. Nine of the 21 physicians were fully qualified general practitioners, while the remainder were non-specialized (NSs) physicians who had recently graduated from the University of Crete, Medical School. A questionnaire of 20 items based on current bronchial asthma clinical guidelines was used. Three scores, the mean total, knowledge subscore and attitudes subscore, were calculated for each group of physicians, both before and after the course. RESULTS: At baseline mean total score and knowledge and attitudes subscores were higher for non-specialized physicians than for the general practitioners, but the differences were not statistically significant (p > 0.05). The knowledge subscore was improved in both groups, however the difference was statistically significant only for the non-specialized physicians (t = 2.628, d.f. = 11, p < 0.05). The mean total score after the course was significantly higher for the non-specialized physicians in comparison to that of the general practitioners (t=-2.688, d.f. = 19, p < 0.05). CONCLUSIONS: This study adds to the information about the success of continuing medical education, and also demonstrates that the recent graduates in the studied population, could be educated with more positive results than the fully qualified practitioner

Automated office blood pressure measurements in primary care are misleading in more than one third of treated hypertensives: The VALENTINE-Greece Home Blood Pressure Monitoring study

Abstract Background This study assessed the diagnostic reliability of automated office blood pressure (OBP) measurements in treated hypertensive patients in primary care by evaluating the prevalence of white coat hypertension (WCH) and masked uncontrolled hypertension (MUCH) phenomena. Methods Primary care physicians, nationwide in Greece, assessed consecutive hypertensive patients on stable treatment using OBP (1 visit, triplicate measurements) and home blood pressure (HBP) measurements (7 days, duplicate morning and evening measurements). All measurements were performed using validated automated devices with bluetooth capacity (Omron M7 Intelli-IT). Uncontrolled OBP was defined as ≥140/90 mmHg, and uncontrolled HBP was defined as ≥135/85 mmHg. Results A total of 790 patients recruited by 135 doctors were analyzed (age: 64.5 ± 14.4 years, diabetics: 21.4%, smokers: 20.6%, and average number of antihypertensive drugs: 1.6 ± 0.8). OBP (137.5 ± 9.4/84.3 ± 7.7 mmHg, systolic/diastolic) was higher than HBP (130.6 ± 11.2/79.9 ± 8 mmHg; difference 6.9 ± 11.6/4.4 ± 7.6 mmHg, p Conclusions In primary care, automated OBP measurements are misleading in approximately 40% of treated hypertensive patients. HBP monitoring is mandatory to avoid overtreatment of subjects with WCH phenomenon and prevent undertreatment and subsequent excess cardiovascular disease in MUCH

UV Leo: The binary with the two suns

BV light curves of the eclipsing binary UV Leo obtained at the Kryonerion Astronomical Station of the National Observatory of Athens, Greece, are analyzed. The analysis is based on a Roche configuration with two spots on the secondary surface. The elements of the two components of the system are calculated and the spot characteristics are given

A study of the binary GR Tauri from optical and infrared observations

Visual and infrared light curves of the noncontact, short period, close binary system GR Tauri were obtained in 1992 November. A new ephemeris of the binary is given using the times of minima inferred from all the observations of the system to date. New light and photometric data from the analysis of the B, V and J, K light curves via the Wilson-Devinney code are also given, resulting in a &quot;near-contact&quot; binary model for the system. The analysis of the colors of GR Tauri shows that the primary component&apos;s spectral type must be about A9 V, instead of A5 V according to a recent spectroscopic classification. © 1995 American Astronomical Society

Study of the contact binary AK Herculis: Light-curve analysis and orbital period investigation

AK Her is a very interesting contact binary exhibiting variable light curves and an obvious O&apos;Connell effect, with max I greater than max II. In the present work an extensive study of this system is made covering not only its light curve analysis, but also its orbital period changes in an attempt to give a definite answer regarding the apsidal motion of AK Her. Photoelectric observations of AK Her, obtained between 1985-1987 at the National Observatory of Athens Greece, are presented, analysed and discussed. The light curve analysis was made with the W-D code and the geometric and photometric elements of the system were derived. The O&apos;Connell effect was faced with a two dark spot model. Moreover, the orbital period of the system was examined and two periodicities were detected. Since the first one corresponds to the time interval for which observational data exist and the second was found to be half of the first, it turns out that none of them is true. Two other significant results that came from the present analysis are that the orbital period of AK Her does not follow a sinusoidal variation and that, from the times of minimum light at primary and secondary eclipses, it seems that there is no apsidal motion