Scalar mesons in radiative \phi\to K^0\bar{K}^0\gamma decay

We study the radiative $\phi\to K^0\bar{K}^0\gamma$ decay within a phenomenological framework by considering the contributions of the $f_{0}(980)$ and $a_{0}(980)$ scalar resonances. We calculate the branching ratio $B(\phi\to K^0\bar{K}^0\gamma)$ by employing the coupling constants $g_{f_0K^{+}K^{-}}$ and $g_{a_0K^{+}K^{-}}$ as determined by different experimental groups.Comment: 10 pages, 3 figure

A Real Time Image Processing Subsystem: GEZGIN

In this study, a real-time image processing subsystem, GEZGIN, which is currently being developed for BILSAT-1, a 100kg class micro-satellite, is presented. BILSAT-1 is being constructed in accordance with a technology transfer agreement between TÜBITAK-BILTEN (Turkey) and SSTL (UK) and planned to be placed into a 650 km sunsynchronous orbit in Summer 2003. GEZGIN is one of the two Turkish R&D payloads to be hosted on BILSAT-1. One of the missions of BILSAT-1 is constructing a Digital Elevation Model of Turkey using both multi-spectral and panchromatic imagers. Due to limited down-link bandwidth and on-board storage capacity, employment of a realtime image compression scheme is highly advantageous for the mission. GEZGIN has evolved as an implementation to achieve image compression tasks that would lead to an efficient utilization of both the down-link and on-board storage. The image processing on GEZGIN includes capturing of 4-band multi-spectral images of size 2048x2048 8- bit pixels, compressing them simultaneously with the new industry standard JPEG2000 algorithm and forwarding the compressed multi-spectral image to Solid State Data Recorders (SSDR) of BILSAT-1 for storage and down-link transmission. The mission definition together with orbital parameters impose a 6.5 seconds constraint on real-time image compression. GEZGIN meets this constraint by exploiting the parallelism among image processing units and assigning compute intensive tasks to dedicated hardware. The proposed hardware also allows for full reconfigurability of all processing units

Fear of COVID-19 lead to procrastination among Turkish university students: the mediating role of intolerance of uncertainty

Background: The COVID-19 outbreak has not only increased mortality but has also negatively affected mental health among populations across the world. Furthermore, individuals are experiencing uncertainty about their current and future situation because of the pandemic. Therefore, the present study investigated the mediating role of intolerance of uncertainty in the relationship between fear of COVID-19 and procrastination among a sample of Turkish university students. Methods: Between October and November 2020, 450 university students (291 females and 159 males aged 17 to 24 years) from three state universities in Turkey completed an online survey. Correlation analysis and structural equation modeling methods were employed to examine a model for understanding the general procrastination during COVID-19 pandemic. Results: The results of the correlation analysis indicated that the fear of COVID-19 was positively correlated with both intolerance of uncertainty (r = .26, p < .001) and procrastination (r = .23, p < .001). The mediation analysis also showed that intolerance of uncertainty had a significant mediating role in the relationship between fear of COVID-19 and procrastination (β = .11, p < .001). Conclusion: Reducing the fear of COVID-19 and intolerance of uncertainty is likely to contribute to reducing individuals’ procrastination behaviors during the pandemic

Radiative pion capture by a nucleon

The differential cross sections for $\pi^- p \to \gamma n$ and $\pi^+ n \to \gamma p$ are computed up to $O(p^3)$ in heavy baryon chiral perturbation theory (HBChPT). The expressions at $O(p)$ and $O(p^2)$ have no free parameters. There are three unknown parameters at $O(p^3)$, low energy constants of the HBChPT Lagrangian, which are determined by fitting to experimental data. Two acceptable fits are obtained, which can be separated by comparing with earlier dispersion relation calculations of the inverse process. Expressions for the multipoles, with emphasis on the p-wave multipoles, are obtained and evaluated at threshold. Generally the results obtained from the best of the two fits are in good agreement with the dispersion relation predictions.Comment: 24 pages, Latex, using RevTe

Plasma scale length effects on protons generated in ultra-intense laser–plasmas

The energy spectra of protons generated by ultra-intense (1020 W cm−2) laser interactions with a preformed plasma of scale length measured by shadowgraphy are presented. The effects of the preformed plasma on the proton beam temperature and the number of protons are evaluated. Two-dimensional EPOCH particle-in-cell code simulations of the proton spectra are found to be in agreement with measurements over a range of experimental parameter

Investigation of overall and melamine migration from melamine bowls

Overall and melamine migration have been determined for 60 samples of melamine resin bowls, which were purchased in various local markets in the area of Bursa, Turkey. The samples were exposed to food simulants 3% acetic acid, 10% ethanol aqueous solutions, and rectified (refined) olive oil at 100 °C for 30 min, and 50% ethanol aqueous solutions at 60 °C for 30 min. The LOQ value was calculated as 3.3 mg dm−2 for overall migration and 0.126 mg kg-1 for melamine migration. Research findings did not exceed the limit of overall migration level (10 mg dm−2). Also, melamine levels of all tested items found in the third assays were below the specific migration limit (SML) of 2.5 mg kg−1 set out in the EU 10/2011 (EU, 2011) and Turkish Food Codex 2013/34 (TFC, 2013a). Some expensive as well as cheap products showed close migration levels. The increased cost of the item did not indicate a higher quality regarding health in this study