Gravitational waves generated from the cosmological QCD phase transition within AdS/QCD

We study the gravitational waves produced by the collision of the bubbles as a probe for the cosmological first order QCD phase transition, considering heavy static quarks. Using AdS/QCD and the correspondence between a first order Hawking-Page phase transition and confinement-deconfinement phase transition, we find the spectrum and the strain amplitude of the gravitational wave within the hard and soft wall models. We postulate the duration of the phase transition corresponds to the evaporation time of the black hole in the five dimensional dual gravity space, and thereby obtain a bound on the string length in the space and correspondingly on the duration of the QCD phase transition. We also show that IPTA and SKA detectors will be able to detect these gravitational waves, which can be an evidence for the first order deconfinement transition.Comment: v2: The effects of sound waves and the magnetohydrodynamic turbulence on the GW spectrum have been studied. Version published in PL

The cosmic QCD phase transition with dense matter and its gravitational waves from holography

Consistent with cosmological constraints, there are scenarios with the large lepton asymmetry which can lead to the finite baryochemical potential at the cosmic QCD phase transition scale. In this paper, we investigate this possibility in the holographic models. Using the holographic renormalization method, we find the first order Hawking-Page phase transition, between Reissner-Nordstr$\rm\ddot{o}$m AdS black hole and thermal charged AdS space, corresponding to the de/confinement phase transition. We obtain the gravitational wave spectra generated during the evolution of bubbles for a range of the bubble wall velocity and examine the reliability of the scenarios and consequent calculations by gravitational wave experiments.Comment: 18 pages , 4 figures, references and new discussions added, accepted to be published in Phys. Lett.

Electroweak phase transition in the presence of hypermagnetic field and the generation of gravitational waves

We investigate the effects of a large-scale background hypermagnetic field on the electroweak phase transition. We propose an effective weak angle which varies during the electroweak phase transition and upon its use, show that for a strong enough hypermagnetic field the phase transition occurs in two steps and becomes first-order. We obtain all of the important quantities characterizing the details of the phase transition, including the latent heat, transition temperature and duration. We then explore one of the consequences of this model which is the generation of gravitational waves. We calculate the gravitational wave energy spectrum generated during the first-order electroweak phase transition and find that, for strong enough background hypermagnetic fields, these signals can be detected by the Ultimate-DECIGO interferometer.Comment: 19 pages, 7 figures; v3: more discussions adde

Matter and dark matter asymmetry from a composite Higgs model

We propose a low scale leptogenesis scenario in the framework of composite Higgs models supplemented with singlet heavy neutrinos. One of the neutrinos can also be considered as a dark matter candidate whose stability is guaranteed by a discrete $\mathbb{Z}_2$ symmetry of the model. In the spectrum of the strongly coupled system, bound states heavier than the pseudo Nambu-Goldstone Higgs boson can exist. Due to the decay of these states to heavy right-handed neutrinos, an asymmetry in the visible and dark sector is simultaneously generated. The resulting asymmetry is transferred to the standard model leptons which interact with visible right-handed neutrinos. We show that the sphaleron-induced baryon asymmetry can be provided at the TeV scale for resonant bound states. Furthermore, depending on the coupling strength of dark neutrino interaction, a viable range of the dark matter mass is allowed in the model.Comment: 12 pages, 2 figures,v2: new comments on composite setup adde

Electroweak baryogenesis via chiral gravitational waves

We propose a new mechanism for electroweak baryogenesis based on gravitational waves generated by helical magnetic fields that are present during a first order electroweak phase transition. We generate a net lepton number through the gravitational chiral anomaly which appears due to the chiral gravitational waves produced by these magnetic fields. The observed value of baryon asymmetry can be obtained in our mechanism within parameter space of scenarios with an inverse cascade evolution for magnetic fields which can also be candidates for large-scale magnetic fields.Comment: 10 pages, Published versio

Effect of melatonin in reducing second-generation antipsychotic metabolic effects: A double blind controlled clinical trial

Introduction The use of second-generation atypical antipsychotics has an increasing role in the development of metabolic syndrome. However, these medications due to metabolic disorders can lead to an increased risk of cardiovascular disease and subsequently mortality as well as reduced adherence to treatment. The main objective of current study was to determine the ability of melatonin to reduce the metabolic effects of second-generation antipsychotics. Methods This double blind controlled clinical trial was conducted on 100 patients aged 18–64 years old were treated with the second-generation antipsychotics for the first time. The patients were divided randomly into two groups of 50. The case group received slow-release melatonin at a dose of 3 mg and the control group was given oral placebo at 8 p.m. Results The findings in melatonin group indicated significantly increase of HDL and decreased fasting blood sugar and systolic blood pressure, as well as had statistically significant increase in waist circumference, weight and BMI compared with placebo group. Conclusion According to the findings, it can be claimed that the addition of melatonin to atypical antipsychotics has led to a reduction in some of the metabolic effects of these drugs. In this study, HDL level was increased, and the mean systolic blood pressure and FBS were decreased in the melatonin group. Considering that these factors are contributing to cardiovascular disease as a leading cause of mortality in psychiatric patients, so the use of melatonin can reduce some of the medical effects of long-term treatment of atypical antipsychotics. © 2017 Diabetes Indi

Psychological Violence in the Health Care Settings in Iran: A Cross-Sectional Study

Background: Psychological violence is the most common form of workplace violence that can affect professional performance and job satisfaction of health care workers. Although several studies have been conducted in Iran, but there is no consensus regarding current status of such violence. Objectives: This study aimed to investigate the prevalence of psychological violence among healthcare workers employed at teaching hospitals in Iran. Patients and Methods: In this cross-sectional study, 5874 health professionals were selected using multistage random sampling. Data were collected using a self-administered questionnaire developed by the International Labor Organization, International Council of Nurses, World Health Organization, and Public Services International. Descriptive statistics were used to analyze the data. Results: It was found that 74.7% of the participants were subjected to psychological violence during the past 12 months. Totally, 64.5% of psychological violence was committed by patients’ families, but 50.9% of participants had not reported the violence, and 69.9% of them believed that reporting was useless. Conclusions: The results are indicative of high prevalence of psychological violence against healthcare workers. Considering non-reporting of violence in more than half of participants, use of an appropriate reporting system and providing training programs for health professionals in order to prevent and manage workplace violence are essential