4 research outputs found

    Precise Calculation of Single and Double Ionization of Hydrogen Molecule in Intense Laser Pulses

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    A new simulation box setup is introduced for the precise description of the wavepacket evolution of two electronic systems in intense laser pulses. In this box, the regions of the hydrogen molecule H2_{2} , and singly and doubly ionized species, H2+_{2}^+ and H2+2_{2}^{+2} , are well recognized and their time-dependent populations are calculated at different laser field intensities. In addition, some new regions are introduced and characterized as quasi-double ionization and their time-dependencies on the laser field intensity are calculated and analyzed. The adopted simulation box setup is special in that it assures proper evaluation of the second ionization. In this study, the dynamics of the electrons and nuclei of the hydrogen molecule are separated based on the adiabatic approximation. The time-dependent Schr\"{o}dinger and Newton equations are solved simultaneously for the electrons and the nuclei, respectively. Laser pulses of 390 nm wavelength at four different intensities (i.e. 1×1014 1\times10^{14} , 5×1014 5\times10^{14} , 1×1015 1\times10^{15} , and 5×1015 5\times10^{15} W cm2^{-2}) are used in these simulations. Details of the central H2_{2} region is also presented and discussed. This region is divided into four sub-regions related to the ionic state H+^+H^- and covalent (natural) state HH. The effect of the motion of nuclei on the enhanced ionization is discussed. Finally, some different time-dependent properties are calculated and their dependencies on the intensity of the laser pulse are studied, and their correlations with the populations of different regions are analyzed.Comment: 30 pages, 17 figure

    Ameliorative effects of aerobic training in girls with precocious puberty: role of leptin and ghrelin

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    Abstract This study was an attempt to examine the changes in serum levels of ghrelin and leptin after 12-weeks of aerobic training and gonadotropin releasing hormone agonist (GnRH) treatment in girls with central precocious puberty. Thirty girls (6–8 years old) with precocious puberty who had received Triptorelin were randomly divided in two groups (medication and medication + training). Fifteen age-matched healthy girls (without precocious puberty) were also included as the control group. The medication + training group submitted an aerobic training program for 3 days/week with 20–75 min per day and 45–75% of maximum heart rate for 12-weeks. Serum levels of leptin, ghrelin, cholesterol, triglycerides and body mass index (BMI) were determined at baseline and 48 h after the last training session. The results indicated that leptin significantly decreased (p = 0.001) and ghrelin significantly increased (p = 0.001) in the medication + training group but no significant difference was observed in the ghrelin (p = 1) and leptin (p = 0.78) in the medication group. Leptin to ghrelin ratio indicated a decrease in medicine + training group (p = 0.028). Ghrelin were negatively correlated with leptin and BMI. The data indicated that aerobic training increased ghrelin and reduced leptin and leptin to ghrelin ratio but GnRH agonist treatment had no effect on plasma leptin and ghrelin levels

    One-year prevalence and the association between SARS-CoV-2 cycle threshold, comorbidity and outcomes in population of Babol, North of Iran (2020-2021).

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    Background: The present study aimed to investigate the one-year prevalence of SARS-CoV-2, common comorbidities and demographic information among negative- and positive rRT-PCR in health care workers (HCW), hospitalized and outpatients. Also, the association between SARS-CoV-2 cycle threshold (Ct) and the outcomes of patients were analyzed in Babol, northern Iran. Methods: This large retrospective cross-sectional study was performed between March 2020 and March 2021. The records of 19232 hospitalized, outpatients and HCW suspected to COVID-19 were collected from teaching hospitals in the North of Iran. Results: Out of the 19232 suspected to COVID-19 patients, 7251 (37.7) had a positive rRT-PCR result; 652 (9), 4599 (63.4) and 2000 (27.6) of those were categorized as HCW, hospitalized and outpatients, respectively. Moreover, between the hospitalized and the outpatient group, 10.2 and 0.8 cases died, whereas no death cases were reported in the HCW. Furthermore, it seems that death rate was significantly different between the three groups of Ct value, the highest mortality in those with Ct between 21 and 30 (group B=7.6) and the lowest in the group with the highest Ct (between 31 and 40 = 5.5) (p<0.001). Conclusion: In summary, 37.7 of cases were positive for SARS-CoV-2; of which, 63.4, 27.6 and 9 were hospitalized, outpatients and HCW, respectively. With regard to the mortality rate in hospitalized patients and the significant association with Ct under 20 and 30, it seems that the early detection and the initial quantification of SARS-CoV-2 in the first week of the conflict and therapeutic considerations to reduce the relative load can reduce the mortality rate
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