Probe Branes Thermalization in External Electric and Magnetic Fields

We study thermalization on rotating probe branes in AdS_5 x S^5 background in the presence of constant external electric and magnetic fields. In the AdS/CFT framework this corresponds to thermalization in the flavour sector in field theory. The horizon appears on the worldvolume of the probe brane due to its rotation in one of the sphere directions. For both electric and magnetic fields the behaviour of the temperature is independent of the probe brane dimension. We also study the open string metric and the fluctuations of the probe brane in such a set-up. We show that the temperatures obtained from open string metric and observed by the fluctuations are larger than the one calculated from the induced metric.Comment: 27 pages, 7 figure

Sodium benzoate and potassium sorbate preservatives in food stuffs in Iran

A high-performance liquid chromatography method was applied for the determination of the levels of benzoate and sorbate in 400 food samples, including pickled cucumbers, canned tomato pastes, sour cherry jams, soft drinks, fruit juices and dairy products (UF-Feta cheeses, Lighvan cheeses, lactic cheeses, yogurts and doogh). The results showed that 270 (67.5%) of all samples contained benzoate ranging from 11.9 to 288.5 mg kg⁻¹ in lactic cheese and fruit juice, respectively. The levels of sorbate in 98 (24.5%) of the samples were 20.1 to 284.3 mg kg⁻¹ in doogh and fruit juice, respectively. Moreover, benzoate was detected in all dairy products ranging from 11.9 mg kg⁻¹ in lactic cheese to 91.2 mg kg⁻¹ in UF-Feta cheese. A low concentration of benzoate could originate naturally, due to specific biochemical mechanisms during cheese, yogurt and doogh maturation. In conclusion, a minimum level for benzoate in dairy products should be defined in the legislation. © 2015 Taylor & Francis

Global limits on kinetic Alfv\'{e}non speed in quasineutral plasmas

Large amplitude kinetic Alfv\'{e}non (exact Alfv\'{e}n soliton) matching condition is investigated in quasineutral electron-ion and electron-positron-ion plasmas immersed in a uniform magnetic field. Using the standard pseudopotential method, the magnetohydrodynamics (MHD) equations are exactly solved and a global allowed matching condition for propagation of kinetic solitary waves is derived. It is remarked that, depending on the plasma parameters, the kinetic solitons can be sub- or super-Alfv\'{e}nic, in general. It is further revealed that, either upper or lower soliton speed-limit is independent of fractional plasma parameters. Furthermore, the soliton propagation angle with respect to that of the uniform magnetic field is found to play a fundamental role in controlling the soliton matching speed-range.Comment: To be published in Physics of Plasma

Causes of the failure of the state in Syria (2010-2019)

What broke out as the Arab Spring in Tunisia in 2010 stroke Egypt and shed its light on the Middle East, including Syria. During the first few days of demonstrations in Syria, the spring turned into a bloody fall and a full-scale civil war. Political-security crises and economic and social problems that had dominated the country during Assad's family rule left the state in deep defeat. Meanwhile, the arena of war turned into the scene of conflict between different political forces and their regional and international supporters, caused Syria to encounter immense foreign intervention. In this regard, this article attempts to figure out the answer to this question, "What are the causes for the Syrian state of failing during 2010-19?" The authors hypothesize that "the state in Syria has failed since the beginning of the protests due to persistent social, economic and political-security crises that led to the militarization of the country by the opposition and insurgent groups." The findings also indicate that the Syrian state faced historical crises after 2010 in economic imbalance and decline, demographic and environmental pressures, political-administrative corruption, and weak public services, which deepened after 2011, and it spread to other areas such as ethnic-religious violence

A generalization of heterochromatic graphs

In 2006, Suzuki, and Akbari & Alipour independently presented a necessary and sufficient condition for edge-colored graphs to have a heterochromatic spanning tree, where a heterochromatic spanning tree is a spanning tree whose edges have distinct colors. In this paper, we propose $f$-chromatic graphs as a generalization of heterochromatic graphs. An edge-colored graph is $f$-chromatic if each color $c$ appears on at most $f(c)$ edges. We also present a necessary and sufficient condition for edge-colored graphs to have an $f$-chromatic spanning forest with exactly $m$ components. Moreover, using this criterion, we show that a $g$-chromatic graph $G$ of order $n$ with $|E(G)|>\binom{n-m}{2}$ has an $f$-chromatic spanning forest with exactly $m$ ($1 \le m \le n-1$) components if $g(c) \le \frac{|E(G)|}{n-m}f(c)$ for any color $c$.Comment: 14 pages, 4 figure

Mindfulness Training and Quality of Life Among Pregnant Women: A Randomized Clinical Trial

quality of life (QOL). Objectives: The current study aimed to examine the effect of mindfulness training on QOL among pregnant females. Methods: In this clinical trial, 80 pregnant females eligible for inclusion were selected by convenience sampling method from Akramian, Taleghani and Ketabchi health centers in Kashan, Iran. The participants were randomly allocated into experimental and control groups (n = 40, each group) by block randomization method. Females in the experimental group received eight sessions of 90-minute mindfulness training, while females in the control group only received routine prenatal care services. Data were collected using a demographic questionnaire and a short-form 36 (SF-36) health survey questionnaire to measure the QOL. Chi-square, independent samples T-test and repeated measures analysis of variance were used to analyze the data. Results: The results showed that the totalQOLscore and subscales of emotional role functioning, vitality, mental health, social functioning and general health in the experimental group had significant changes compared to those of the control group. However, there was no significant difference between other subscales. The mean total QOL score before intervention was 44.84 � 4.44 and after intervention and follow-up was 50.42�3.71 and 49.42�5.24, respectively (P < 0.05). Conclusions: Mindfulness training can be used as a psychological prenatal care to moderate negative emotions, improve social functioning and cope with psychological and physical changes