Dynamical evolution of active detached binaries on log Jo - log M diagram and contact binary formation

Orbital angular momentum (Jo), systemic mass (M) and orbital period (P) distributions of chromospherically active binaries (CAB) and W Ursae Majoris (W UMa) systems were investigated. The diagrams of log Jo - log P, log M - log P and log Jo-log M were formed from 119 CAB and 102 W UMa stars. The log Jo-log M diagram is found to be most meaningful in demonstrating dynamical evolution of binary star orbits. A slightly curved borderline (contact border) separating the detached and the contact systems was discovered on the log Jo - log M diagram. Since orbital size (a) and period (P) of binaries are determined by their current Jo, M and mass ratio q, the rates of orbital angular momentum loss (dlog Jo/dt) and mass loss (dlog M/dt) are primary parameters to determine the direction and the speed of the dynamical evolution. A detached system becomes a contact system if its own dynamical evolution enables it to pass the contact border on the log Jo - log M diagram. Evolution of q for a mass loosing detached system is unknown unless mass loss rate for each component is known. Assuming q is constant in the first approximation and using the mean decreasing rates of Jo and M from the kinematical ages of CAB stars, it has been predicted that 11, 23 and 39 cent of current CAB stars would transform to W UMa systems if their nuclear evolution permits them to live 2, 4 and 6 Gyrs respectively.Comment: 28 pages, including 6 figures and 2 tables, accepted for publication in MNRA

Impact of clinicopathological variables on laparoscopic hysterectomy complications, a tertiary center experience

Objectives: To analyze intraoperative and postoperative complications according to Clavian-Dindo Classification (CDC) and evaluate the influence of clinicopathological features on the feasibility and safety of total laparoscopic hysterectomy (TLH) in patients that underwent surgery in a tertiary center. Material and methods: We retrospectively reviewed the database of 469 patients that underwent surgery for patients who underwent extra facial TLH from 2013 to 2020. Results: A total of 86 (18.3%) peri-postoperative complications were observed. The incidence of intraoperative complications was 2% (n = 10). The overall conversion rate to open surgery was 1.9% (n = 9). A total of 76 postoperative complications were observed in 61 patients (14.3%). The incidence of minor (Grade I [n = 16, 3.4%] and II [n = 42, 8.9%]) and major complications (Grade III [n = 15, 3.2%], IV [n = 2, 0.4%] and V [n = 1, 0.2 %]) were 12.3% and 3.8%, respectively. A higher BMI and performing surgery at the first step of learning are found to be associated with intraoperative and postoperative complications (p < 0.05). Postoperative complications related to having a history of the cesarean section, additional comorbidities, and uterine weight ≥ 300 g (p < 0.05). Conclusions: The implementation of TLH by experienced surgeons appears to have remarkable advantages over open surgery. However, the risk factor for complications should be taken into account by surgeons in the learning curve in selecting the appropriate patient for surgery.

Ultracool dwarf benchmarks with \emph{Gaia} primaries

This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society. © 2017 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.We explore the potential of \emph{Gaia} for the field of benchmark ultracool/brown dwarf companions, and present the results of an initial search for metal-rich/metal-poor systems. A simulated population of resolved ultracool dwarf companions to \emph{Gaia} primary stars is generated and assessed. Of order $\sim$24,000 companions should be identifiable outside of the Galactic plane ($|b| > 10\,$deg) with large-scale ground- and space-based surveys including late M, L, T, and Y types. Our simulated companion parameter space covers $0.02 \le M/M_{\odot} \le 0.1$, $0.1 \le {\rm age/Gyr} \le 14$, and $-2.5 \le {\rm [Fe/H]} \le 0.5$, with systems required to have a false alarm probability $$0.6\, kau}\,Peer reviewedFinal Accepted Versio

SiC polytypes and doping nature effects on electrical properties of ZnO-SiC Schottky diodes

Electrical properties of ZnO/SiC Schottky diodes with two SiC polytypes and N and P doping are investigated. Characterization was performed through I–V and C–V–f measurements. Schottky barrier height (Φb), ideality factor (n), and series resistance (Rs) were extracted from forward I–V characteristics. (Φb), carrier’s concentrations (Nd-Na) and (Rs) frequency dependence were extracted from C–V–f characteristics. The extracted n values suggest that current transport is dominated by interface generation-recombination and/or barrier tunneling mechanisms. When changing SiC polytypes, the rectifying ratio of ZnO/n-4HSiC is found to be twice that of ZnO/n-6HSiC. A change in doping nature gave a leakage current ratio of 40 between ZnO/p-4HSiC and ZnO/n- 4HSiC. These results indicate that ZnO/p-4HSiC diodes have a complex current transport compared to diodes on n-type SiC. From I-V measurements, barrier height values are 0.63eV, 0.65eV and 0.71 eV for heterojunction grown on n-6HSiC, n-4HSiC and p-4HSiC, respectively. C-V measurements gave higher values indicating the importance of interface density of states. Nss values at 1MHz frequency are 4.54×1011 eV-1 cm-2, 3×1012 eV-1 cm-2 and 8.13×1010 eV-1 cm-2 for ZnO/n-6HSiC, ZnO/n-4HSiC and ZnO/p-4HSiC, respectively. Results indicate the importance of SiC polytypes and its doping natur

A catalog of chromospherically active binary stars (third edition)

Chromospherically Active Binaries (CAB) catalogue have been revised and updated. With 203 new identifications, the number of CAB stars is increased to 409. Catalogue is available in electronic format where each system has various number of lines (sub-orders) with a unique order number. Columns contain data of limited number of selected cross references, comments to explain peculiarities and position of the binarity in case it belongs to a multiple system, classical identifications (RS CVn, BY Dra), brightness and colours, photometric and spectroscopic data, description of emission features (Ca II H&K, $H_{\alpha}$, UV, IR), X-Ray luminosity, radio flux, physical quantities and orbital information, where each basic entry are referenced so users can go original sources.Comment: 5 pages, including 2 figures and 3 tables, accepted for publication in MNRA

Discovery of the benchmark metal poor T8 dwarf BD+01 2920B

We have searched the WISE first data release for widely separated (<10,000AU) late T dwarf companions to Hipparcos and Gliese stars. We have discovered a new binary system containing a K-band suppressed T8p dwarf WISEP J1423+0116 and the mildly metal poor ([Fe/H]=-0.38+-0.06) primary BD+01 2920 (Hip 70319), a G1 dwarf at a distance of 17.2pc. This new benchmark has Teff=680+-55K and a mass of 20-50 Mjup. Its spectral properties are well modelled except for known discrepancies in the Y and K bands. Based on the well determined metallicity of its companion, the properties of BD+01 2920B imply that the currently known T dwarfs are dominated by young low-mass objects. We also present an accurate proper motion for the T8.5 dwarf WISEP J075003.84+272544.8.Comment: MNRAS, accepted 2012 January 1

Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

The power of language tests in Turkish context: A critical study

High-stakes tests are often introduced to bring about change on educational practices and thus lead to pedagogical reform. The Field Knowledge Test (FKT) for teacher candidates of English in Turkey is an example of such an attempt. This study aims to giving voice to English language teacher educators and student teachers to view the FKT critically to investigate if it has brought about the intended changes and its impact on its main stakeholders. The study, first, presents Critical Language Testing (CLT). Then, it gives information on the context of the study. Data collection for the study involved 153 test takers and 23 teacher educators working at ELT Departments in Turkey. Two open-ended questionnaires were used to survey participants’ perceptions of the FKT in terms of its impact on the nature of education they receive, their attitudes and feelings and also on their academic and personal lives. Analysis of data paved the way for further studies on how high stakes tests might or might not be efficient agents of change in various educational contexts. © 2019 JLLS and the Authors - Published by JLLS