Peculiar Glitch of PSR J1119-6127 and Extension of the Vortex Creep Model

Glitches are sudden changes in rotation frequency and spin-down rate, observed from pulsars of all ages. Standard glitches are characterized by a positive step in angular velocity ($\Delta\Omega$ $>$ $0$) and a negative step in the spin-down rate ($\Delta \dot \Omega$ $<$ $0$) of the pulsar. There are no glitch-associated changes in the electromagnetic signature of rotation-powered pulsars in all cases so far. For the first time, in the last glitch of PSR J1119-6127, there is clear evidence for changing emission properties coincident with the glitch. This glitch is also unusual in its signature. Further, the absolute value of the spin-down rate actually decreases in the long term. This is in contrast to usual glitch behaviour. In this paper we extend the vortex creep model in order to take into account these peculiarities. We propose that a starquake with crustal plate movement towards the rotational poles of the star induces inward vortex motion which causes the unusual glitch signature. The component of the magnetic field perpendicular to the rotation axis will decrease, giving rise to a permanent change in the pulsar external torque.Comment: accepted by MNRAS, 10 pages, 2 figure

Non-detection in a Fermi/LAT observation of AXP 4U 0142+61: magnetars?

Significant research in compact stars is currently focused on two kinds of enigmatic sources: anomalous X-ray pulsars (AXPs) and soft gamma-ray repeaters (SGRs). Although AXPs and SGRs are popularly thought to be magnetars, other models (e.g. the accretion model) to understand the observations can still not be ruled out. It is worth noting that a non-detection in a Fermi/LAT observation of AXP 4U 0142+61 has been reported recently by Sasmaz Mus & Gogus. We propose here that Fermi/LAT observations may distinguish between the magnetar model and the accretion model for AXPs and SGRs. We explain how this null observation of AXP 4U 0142+61 favors the accretion model. Future Fermi/LAT observations of AXP 1E 1547.0-5408 and AXP 1E 1048.1-5937 are highly recommended.Comment: 10 pages, 3 figures, Accepted for publication in ApJ(Letters

Burst Tails from SGR J1550-5418 Observed with Rossi X-ray Timing Explorer

We present the results of our extensive search using the Bayesian block method for long tails following short bursts from a magnetar, SGR J1550-5418, over all RXTE observations of the source. We identified four bursts with extended tails, most of which occurred during its 2009 burst active episode. The durations of tails range between ~13 s and over 3 ks, which are much longer than the typical duration of bursts. We performed detailed spectral and temporal analysis of the burst tails. We find that the spectra of three tails show a thermal nature with a trend of cooling throughout the tail. We compare the results of our investigations with the properties of four other extended tails detected from SGR 1900+14 and SGR 1806-20 and suggest a scenario for the origin of the tail in the framework of the magnetar model.Comment: 10 pages, 7 figures, 4 tables, accepted for publication in Ap

Determination of depression risk factors in children and adolescents by regression tree methodology.

We used a regression tree method (RTM) to determine risks of depression in children/adolescents. The survey records of 4,143 children/adolescents in a study based in Mersin, Turkey served as data in this study, and multi-step, stratified, and cluster sampling were used. Effects of 24 variables (sex, smoking, parental problems, etc.) were evaluated on depression scores. The Child Beck Depression Inventory (CBDI) was used to determine the level of depression. Subjects were into 12 different groups based on magnitudes of mean depression scores. The interactions among 7 variables determined to be risk factors are shown on a schema. The STATISTICA (ver.6.0) package program was used for all computations. Although traditional statistical methods have often been used for analysis in this field, such approaches are associated with certain disadvantages such as missing values, ignorance of interaction effects, or restriction of the shape of the distribution. To avoid such disadvantages, we therefore suggest the use of the RTM in studies involving numerical-based outcome variables and for the investigation of a large number of variables and it may be more effective than traditional statistical methods in epidemiological studies which determine risk factors.</p

SELF, PEER AND TEACHER ASSESSMENTS: WHAT IS THE LEVEL OF RELATIONSHIP BETWEEN THEM?

In this research, self, peer and teacher assessment applications were carried out in a science education course included in the teacher education programme. The purpose of this study was to determine the level of relationship between self, peer and teacher assessment. Another aim of the study was to analyze whether there was reciprocity bias in these assessments. In the research, the pre-service science teachers (203 participants in total) assessed themselves and their peers in terms of presentation skills in higher education. The research is a quantitative research that employs descriptive and inferential statistical methods. Self-assessment and peer assessment scores showed moderately high correlations with teacher scores but both were higher than teacher scores. The analyses of reciprocity bias level demonstrated that the scores received or assigned by peers were almost unaffected by bias. On the basis of all these results, it could be argued that self-assessment and peer assessment applications can be used to evaluate presentation skills in teacher education programmes or different tasks in other areas in higher education.  Article visualizations

Laboratory as an Instrument in Improving the Scientific Reasoning Skills of Pre-Service Science Teachers with Different Cognitive Styles

In this study, it was aimed to investigate the effects of guided inquiry learning approach-based laboratory applications on the scientific reasoning skills of pre-service science teachers with different cognitive styles. Additionally, the opinions of pre-service science teachers with different cognitive styles about the effects of the application carried out in the study on the improvement of their scientific reasoning skills were also examined. The sample consisted of five pre-service science teachers studying at a state university in the west of Turkey. In the study, the partially mixed sequential dominant status design, which is a mixed-method research design, was used. The scientific reasoning skills of the participants were determined by using the Classroom Test of Formal Reasoning, and their cognitive styles were identified with the Group Embedded Figures Test. The opinions of the participants were taken through focus group interviews held after the application. As a result of the analysis, it was observed that the participants with field-dependent and field-intermediate cognitive styles achieved more targeted outcomes compared to those with field-independent cognitive styles. The potential relationship of this finding to the use of the guided inquiry learning approach and the hypothetico-deductive reasoning cycle during the applications was analyzed in terms of the concept of information processing, and recommendations were made for researchers

Oxidative Stress in Patients With Nongenital Warts

Comparison of oxidative stress status between subjects with or without warts is absent in the literature. In this study, we evaluated 31 consecutive patients with warts (15 female, 16 male) and 36 control cases with no evidence of disease to determine the effects of oxidative stress in patients with warts. The patients were classified according to the wart type, duration, number, and location of lesions. We measured the indicators of oxidative stress such as catalase (CAT), glucose-6-phosphate dehydrogenase (G6PD), superoxide dismutase (SOD), and malondialdehyde (MDA) in the venous blood by spectrophotometry. There was a statistically significant increase in levels of CAT, G6PD, SOD activities and MDA in the patients with warts compared to the control group (P < .05). However, we could not define a statistically significant correlation between these increased enzyme activities and MDA levels and the type, the duration, the number, and the location of lesions. We determined possible suppression of T cells during oxidative stress that might have a negative effect on the prognosis of the disease. Therefore, we propose an argument for the appropriateness to give priority to immunomodulatory treatment alternatives instead of destructive methods in patients with demonstrated oxidative stress