76 research outputs found
A possible optical counterpart of the X-ray source NuSTARJ053449+2126.0
In this work, we report the observation of a possible optical counterpart to
the recently discovered X-ray source NuSTAR J053449+2126.0. To search for an
optical counterpart of NuSTAR J053449+2126.0 (J0534 in short), we observed the
source with the 1.5-m Telescope (RTT150). Using the B, V, R, and I images of
J0534, we detected the possible optical counterpart of J0534 and determined,
based on our spectral analysis, the source distance for the first time. J0534
could be a high-redshift member of an Active Galactic Nucleus (AGN) sub-group
identified as a quasar. Our analysis favours an accreting black hole of mass
as a power supply for the quasar in J0534.
Further observations in optical and other wavelengths are needed to confirm its
nature.Comment: 7 pages, 4 figure
The first optical light from the supernova remnant G182.4+4.3 located in the Galactic anti-centre region
We report the discovery of optical filamentary and diffuse emission from
G182.4+4.3 using 1.5-m Russian-Turkish telescope. We present the optical CCD
images obtained with Halpha filter revealing the presence of mainly filamentary
structure at the northwest, filamentary and diffuse structure at the centre,
south and north regions of the remnant. The bright optical filaments located in
northwest and south regions are well correlated with the prominent radio shell
of the remnant strongly suggesting their association. From the flux-calibrated
CCD imaging, the average [SII]/Halpha ratio is found to be ~0.9 and ~1.1 for
south and northwest regions, which clearly indicates that the emission
originates from the shock heated gas. We also present the results of X-ray data
obtained from XMM-Newton that show diffuse emission with a very low luminosity
of ~7.3x10^31 erg s^-1 at a distance of 3 kpc in 0.3-10 keV energy band.
Furthermore, we find a surprisingly young age of ~4400 yr for this remnant with
such a large radius of ~22 pc.Comment: 9 pages, 6 figures and 1 table, Accepted for publication in MNRA
Finite-size scaling above the upper critical dimension in Ising models with long-range interactions
The correlation length plays a pivotal role in finite-size scaling and
hyperscaling at continuous phase transitions. Below the upper critical
dimension, where the correlation length is proportional to the system length,
both finite-size scaling and hyperscaling take conventional forms. Above the
upper critical dimension these forms break down and a new scaling scenario
appears. Here we investigate this scaling behaviour in one-dimensional Ising
ferromagnets with long-range interactions. We show that the correlation length
scales as a non-trivial power of the linear system size and investigate the
scaling forms. For interactions of sufficiently long range, the disparity
between the correlation length and the system length can be made arbitrarily
large, while maintaining the new scaling scenarios. We also investigate the
behavior of the correlation function above the upper critical dimension and the
modifications imposed by the new scaling scenario onto the associated Fisher
relation.Comment: 16 pages, 5 figure
Optical Imaging and Spectroscopic Observation of the Galactic Supernova Remnant G85.9-0.6
Optical CCD imaging with H and [SII] filters and spectroscopic
observations of the galactic supernova remnant G85.9-0.6 have been performed
for the first time. The CCD image data are taken with the 1.5m Russian-Turkish
Telescope (RTT150) at TUBITAK National Observatory (TUG) and spectral data are
taken with the Bok 2.3 m telescope on Kitt Peak, AZ.
The images are taken with narrow-band interference filters H, [SII]
and their continuum. [SII]/H ratio image is performed. The ratio
obtained from [SII]/H is found to be 0.42, indicating that the
remnant interacts with HII regions. G85.9-0.6 shows diffuse-shell morphology.
[SII] average flux ratio is calculated from the
spectra, and the electron density is obtained to be 395 . From
[OIII]/H ratio, shock velocity has been estimated, pre-shock density of
, explosion energy of ergs,
interstellar extinction of , and neutral hydrogen column density
of are reported.Comment: 20 pages, 4 tables, 4 figures. Accepted for publication in
Astrophysics & Space Scienc
The incidence of smoking and risk factors for smoking initiation in medical faculty students: cohort study
BACKGROUND: Medical education requires detailed investigation because it is a period during which the attitudes and behaviors of physicians develop. The purpose of this study was to calculate the yearly smoking prevalence and incidence rates of medical faculty students and to identify the risk factors for adopting smoking behaviour. METHODS: This is a cohort study in which every student was asked about their smoking habits at the time of first registration to the medical faculty, and was monitored every year. Smoking prevalence, yearly incidence of initiation of smoking and average years of smoking were calculated in analysis. RESULTS: At the time of registration, 21.8% of the students smoked. At the end of six years, males had smoked for an average of 2.6 ± 3.0 years and females for 1.0 ± 1.8 years (p < 0.05). Of the 93 medical students who were not smokers at the time of registration, 30 (32.3%) were smokers at the end of the 6 years of the course. CONCLUSION: The first 3 years of medical education are the most risky period for initiation of smoking. We found that factors such as being male, having a smoking friend in the same environment and having a high trait anxiety score were related to the initiation of smoking. Targeted smoking training should be mandatory for students in the Medical Faculty
Optical identification and follow-up observations of SRGA J213151.5+491400 -- a new magnetic cataclysmic variable discovered with SRG Observatory
We report results of optical identification and multi-wavelength study of a
new polar-type magnetic cataclysmic variable (MCV), SRGA J213151.5+491400,
discovered by Spectrum Roentgen-Gamma () observatory in the course of the
all-sky survey. We present optical data from telescopes in Turkey (RTT-150 and
T100 at the T\"UBITAK National Observatory), and in Russia (6-m and 1-m at SAO
RAS), together with the X-ray data obtained with and
telescopes aboard and the observatory. We detect SRGA
J213151.5+491400 in a high state in 2020 (17.9 mag) that decreases about 3 mag
into a low state (21 mag) in 2021. We find only one significant period using
optical photometric time series analysis which reveals the white dwarf
spin/orbital period to be 0.059710(1) days (85.982 min). The long slit
spectroscopy in the high state yields a power law continuum increasing towards
the blue with a prominent He II line along with the Balmer line emissions with
no cyclotron humps; consistent with MCV nature. Doppler Tomography confirms the
polar nature revealing ballistic stream accretion along with magnetic stream
during the high state. These characteristics show that the new source is a
polar-type MCV. detections yield an X-ray flux of
(4.0-7.0)10 erg cm s in the high state.
detects a dominating hot plasma component (kT 21 keV in the
high state) declining to (4.0-6.0)10 erg cm s in
2021 (low state). The data obtained in the low state reveal a two-pole
accretor showing a soft X-ray component at (6-7) significance with a
blackbody temperature of 15-18 eV. A soft X-ray component has never been
detected for a polar in the low state before.Comment: 16 pages, 4 Tables and 15 Figures. Accepted for publication in A&A as
it stand
Burnout and psychiatric morbidity among medical students entering clinical training: a three year prospective questionnaire and interview-based study
BACKGROUND: Mental distress among medical students is often reported. Burnout has not been studied frequently and studies using interviewer-rated diagnoses as outcomes are rarely employed. The objective of this prospective study of medical students was to examine clinically significant psychiatric morbidity and burnout at 3(rd )year of medical school, considering personality and study conditions measured at 1(st )year. METHODS: Questionnaires were sent to 127 first year medical students who were then followed-up at 3(rd )year of medical school. Eighty-one of 3(rd )year respondents participated in a diagnostic interview. Personality (HP5-i) and Performance-based self-esteem (PBSE-scale) were assessed at first year, Study conditions (HESI), Burnout (OLBI), Depression (MDI) at 1(st )and 3(rd )years. Diagnostic interviews (MINI) were used at 3(rd )year to assess psychiatric morbidity. High and low burnout at 3(rd )year was defined by cluster analysis. Logistic regressions were used to identify predictors of high burnout and psychiatric morbidity, controlling for gender. RESULTS: 98 (77%) responded on both occasions, 80 (63%) of these were interviewed. High burnout was predicted by Impulsivity trait, Depressive symptoms at 1(st )year and Financial concerns at 1(st )year. When controlling for 3(rd )year study conditions, Impulsivity and concurrent Workload remained. Of the interviewed sample 21 (27%) had a psychiatric diagnosis, 6 of whom had sought help. Unadjusted analyses showed that psychiatric morbidity was predicted by high Performance-based self-esteem, Disengagement and Depression at 1(st )year, only the later remained significant in the adjusted analysis. CONCLUSION: Psychiatric morbidity is common in medical students but few seek help. Burnout has individual as well as environmental explanations and to avoid it, organisational as well as individual interventions may be needed. Early signs of depressive symptoms in medical students may be important to address. Students should be encouraged to seek help and adequate facilities should be available
Mental distress, alcohol use and help-seeking among medical and business students: a cross-sectional comparative study
<p>Abstract</p> <p>Background</p> <p>Stress and distress among medical students are thoroughly studied and presumed to be particularly high, but comparative studies including other student groups are rare.</p> <p>Methods</p> <p>A web-based survey was distributed to 500 medical students and 500 business students. We compared levels of study stress (HESI), burnout (OLBI), alcohol habits (AUDIT) and depression (MDI), and analysed their relationship with self-assessed mental health problems by logistic regression, with respect to gender.</p> <p>Results</p> <p>Medical students' response rate was 81.6% and that of business students 69.4%. Business students scored higher on several study stress factors and on disengagement. Depression (OR 0.61, CI<sub>95 </sub>0.37;0.98) and harmful alcohol use (OR 0.55, CI<sub>95 </sub>0.37; 0.75) were both less common among medical students. However, harmful alcohol use was highly prevalent among male students in both groups (medical students 28.0%, business students 35.4%), and among female business students (25.0%). Mental health problems in need of treatment were equally common in both groups; 22.1% and 19.3%, respectively, and was associated with female sex (OR 2.01, CI<sub>95 </sub>1.32;3.04), exhaustion (OR 2.56, CI<sub>95 </sub>1.60;4.10), lower commitment to studies (OR 1.95, CI<sub>95 </sub>1.09;3.51) and financial concerns (OR 1.81 CI<sub>95 </sub>1.18;2.80)</p> <p>Conclusions</p> <p>Medical students may not be more stressed than other high achieving student populations. The more cohesive structure of medical school and a higher awareness of a healthy lifestyle may be beneficial factors.</p
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