ARTICLE | doi:10.20944/preprints201709.0046.v2
Subject: Physical Sciences, Condensed Matter Physics Keywords: InGaN green LEDs; active region non-uniformity; temperature-dependent electroluminescence; internal quantum efficiency; light extraction efficiency; extended defects; modeling
Online: 12 September 2017 (10:06:36 CEST)
External quantum efficiency of industrial-grade green InGaN light-emitting diodes (LEDs) has been measured in a wide range of operating currents at various temperatures from 13 K to 300 K. Unlike blue LEDs, the efficiency as a function of current is found to have a multi-peak character, which could not be fitted by a simple ABC-model. This observation correlated with splitting of LED emission spectra into two peaks at certain currents. The characterization data are interpreted in terms of non-uniformity of the LED active region, which is tentatively attributed to extended defects like V-pits. We suggest a new approach to evaluation of temperature-dependent light extraction and internal quantum efficiencies taking into account the active region non-uniformity. As a result, the temperature dependence of light extraction and internal quantum efficiencies have been evaluated in the temperature range mentioned above and compared with those of blue LEDs.
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: CD4- CD8 counts; immunity; inflammation; oxidative stress; peak expiratory flow rate
Online: 14 September 2021 (14:43:16 CEST)
Immunity has become an important aspect of concern, as the spread of corona virus, is on the rise. The strategies to boost and modulate the immunity have therefore become need of the hour. The present study was carried out to evaluate the effect of Charak immunity Tablets (CIT) on innate and adaptive immune response in healthy individuals. It was a single-blind, randomized, placebo-controlled, exploratory study. After obtaining Ethics Committee permission, 36 healthy individuals of either sex aged 18-35 years with prior consent were recruited in the study. They were randomly divided into 2 groups to receive either CIT or Placebo in 2:1 ratio. Both the interventions were given in a dose of 1 tab (500 mg) twice daily. The assessment variables were vitals [temperature, pulse, and blood pressure], respiratory health [respiratory rate, oxygen saturation and peak expiratory flow rate], questionnaire based assessment of immune status, perceived stress and quality of life along with objective assessment of immunity [CD4+, CD8+ counts, Interferon gamma (IFN γ), Tumor necrosis factor alpha (TNF-α) and Interleukin 10 (IL-10)] as well as oxidative stress; [Malondialdehyde (MDA) and Glutathione peroxidase], which were assessed at fixed time points. Of 36 recruited participants, only 18 participants completed the study. CIT treated individuals showed a statistically significant improvement in respiratory health, quality of life, perceived stress and subjective immune status. There was a decrease in the levels of serum IFN γ on day 60 compared to baseline. TNF-α and IL-10, both estimated from supernatant of Peripheral Blood Mononuclear Cells (PBMCs) stimulated with lipopolysaccharide (LPS), showed a decrease and a significant increase respectively on day 60 compared to baseline in CIT group. Further, CIT significantly decreased MDA levels.The present study indicates that CIT is an effective and safe drug to boost immunity. However, our findings need to be confirmed in larger sample size using more specific immune parameters.