Localizing gravitational wave sources with optical telescopes and combining electromagnetic and gravitational wave data

Neutron star binaries, which are among the most promising sources for the direct detection of gravitational waves (GW) by ground based detectors, are also potential electromagnetic (EM) emitters. Gravitational waves will provide a new window to observe these events and hopefully give us glimpses of new astrophysics. In this paper, we discuss how EM information of these events can considerably improve GW parameter estimation both in terms of accuracy and computational power requirement. And then in return how GW sky localization can help EM astronomers in follow-up studies of sources which did not yield any prompt emission. We discuss how both EM source information and GW source localization can be used in a framework of multi-messenger astronomy. We illustrate how the large error regions in GW sky localizations can be handled in conducting optical astronomy in the advance detector era. We show some preliminary results in the context of an array of optical telescopes called BlackGEM, dedicated for optical follow-up of GW triggers, that is being constructed in La Silla, Chile and is expected to operate concurrent to the advanced GW detectors.Comment: 8 pages, 8 figures, Proceeding for Sant Cugat Forum for Astrophysic

Особливості та умови формування властивостей техногенних ґрунтів

This work utilises general numerical magnetic resonance imaging MRI simulations to predict the spatial specificity of the blood oxygenation level-dependent (BOLD) functional MRI (fMRI) signal. A Monte Carlo simulation approach was utilized on a microvascular structure consisting of randomly oriented cylinders representing blood vessels. This framework was employed to numerically investigate the spatial specificity, defined as ratio of pial vessel to microvascular signal, of the spin echo BOLD fMRI signal as a function of field strength, echo time and tissue types [grey matter (GM) and cerebrospinal fluid (CSF), respectively]. Spatial specificity of spin echo BOLD fMRI signal was determined to increase with field strength up to 16 T and with maximal specificity for echo time shorter than tissue T(2). In addition, it was found that, for large pial vessels, the extravascular signal decay could not be described using the oversimplified but nevertheless commonly employed mono-exponential signal decay approximation (MEA). Consequently, a recently proposed model relying on the MEA deviates substantially from our results on the spatial specificity. A refinement of this model is proposed based on an available, more detailed signal description. Finally, the effect of CSF on the spatial specificity was investigated. While a large spatial specificity of the spin echo BOLD fMRI signal is observed if a pial vessel is surrounded by grey matter, this is greatly reduced for a pial vessel situated on a GM/CSF interface, rendering the suppression of pial vessels on the cortex surface unlikely

A Feasibility Study of On-Line Excitation System Parameter Estimation

This paper details a feasibility study of estimating excitation system parameters during online operation using time-domain system identification. This study concentrates on identifying the appropriate exciter model, developing an input signal that would provide a proper level of perturbation such that the dynamics of the system can be captured, analyzing the effects of both systematic and random noise, developing algorithms to perform the parameter estimation, testing and validating the obtained system parameters. This study established a strong basis for estimating the system parameters during online operation

Feto-maternal outcome in pregnancy beyond 40 weeks

Background: Fetal, Neonatal and Maternal complications associated with pregnancy beyond 40 weeks have always been underestimated. However emerging evidence demonstrates that the incidence of complications increases after 40 weeks of gestation. The present study conducted to find out the fetomaternal outcome of such prolonged pregnancy.Methods: A prospective cross sectional study of 84 patients with uncomplicated prolonged pregnancy fulfilling the inclusion and exclusion criteria and admitted in department of obstetrics and gynecology at a tertiary care hospital. The aim of the study was to know fetomaternal outcome in pregnancy beyond 40 weeks in consideration of spontaneous and induced labour.Results: Out of 84 patients, 58 (69.05%) were in the age group of 20-30 years, 44 (52.38%) were between 41-42 weeks of gestation according to their LMP and 38(45.24%) were between 40-41 weeks of gestation. In 27 (32.14%) patients mode of delivery was caesarean section, in whom most common indication being fetal distress in 48.15% followed by failure to progress in 22.22%. In present study perinatal morbidity like IUFD, neonatal asphyxia, MAS, RDS were 4.76%, 9.52%, 7.14% and 3.57% respectively. Maternal morbidity like prolonged labor, PPH, fever, wound infection were 10.71%, 5.95%, 3.57% and 3.57% respectively.Conclusions: With Regular antenatal check-up, incidence of postdate pregnancy can be decreased and it is important because of definite risk to fetus as pregnancy continuing beyond 40 weeks of gestation is associated with increased perinatal morbidity and mortality especially those who do not come for regular antenatal check-up. Confirmation of diagnosis of exact term of pregnancy is very important as many patients don’t have regular menstrual history and LMP. Diagnosis can be confirmed by first trimester ultrasound which is most important non-invasive method and readily available

An unusual presentation of primary renal lymphoma: A case report

Lymphomatous involvement of the kidney is often seen as a part of the disseminated disease but primary renal lymphoma is very rare. It is essential to differentiate between renal cell carcinoma and renal lymphoma in patients presenting with renal masses. The prognosis is usually poor with a median survival less than a year. We present the case of a 81-year-old male who presented with type B symptoms and was diagnosed to have primary lymphoma of the kidney and discuss briefly about the primary renal lymphoma

An examination of the effects of self-regulatory focus on the perception of the media richness: the case of email

Communication is a key element in organizations’ business success. The media richness theory and the channel expansion theory are two of the most influential theories regarding the selection and use of communication media in organizations; however, literature has focused little on the effects of self-regulation by managers and employees in these theories. To analyze these topics, this study develops an empirical investigation by gathering data from 600 managers and employees using a questionnaire. The results suggest that the perception of media richness is positively affected when the individual shows a promotion focus or strategy.Peer ReviewedPostprint (author’s final draft