Showing papers by "Manoj Kumar published in 2023"

Post-traumatic stress and depression following a landslide linked to the 2018 floods in Kerala, India: Relevance of screening.

Abstract: There is scant information on early manifestation of trauma due to catastrophic natural events and its relation with stress-related disorders. The specific objective of this study was to estimate and compare the prevalence of post-traumatic stress and depression on day 3 (D3) and week 6 (W6) following the 2018 flood in Kerala, India. In a cross-sectional study, symptoms of post-traumatic stress and depression were studied at D3 using primary care Post-Traumatic Stress Disorder screen for Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) (PC-PTSD-5), and then at W6 using PC-PTSD-5, Screening Questionnaire for Disaster Mental Health, PTSD Checklist for DSM-5 (PCL-5), and Becks Depression Inventory. Majority (70 percent) were screen positive at D3 (n = 20) compared with 30 percent at W6 (n = 50), with a decreased frequency of all symptoms. Being PC-PTSD-5 screen positive at W6 was significantly associated with the presence of threat to life, physical injury, and death of relatives or neighbors. According to PCL-5, at W6, 46 percent had possible PTSD. Except damage to property, other disaster related or sociodemographic variables were not associated with the risk of having PTSD. Positive predictive value of PC-PTSD-5 (D3) for PTSD (PCL-5) at W6 was 64.3 percent. Depression and possibility of PTSD were significantly associated. A considerable proportion of victims continued to have post-traumatic stress and depression although the -frequency decreased over time. A simple screening measure may help to identify victims with possible PTSD.

In-depth insight of thermodynamic and kinetic barrier for computation of nucleation rate and interfacial energy of ultra-small Gd2O3 nanoclusters utilizing non-isothermal thermogravimetric models

Abstract: Determination of temperature-dependent nucleation rate is a crucial parameter to accessing the kinetic and thermodynamic barrier linked with developing subatomic-sized nuclei, which tend to restrain the nucleation process. In this study, we exclusively compute the nucleation rate, thermodynamic parameters, and interfacial energy of ultra-small gadolinium oxide nanoclusters at high temperatures. Here, the apparent value of activation energy (Ea.) and pre-exponential kinetic factor (Aa) was precisely computed by utilizing the most accurate Vyazovkin advanced and KAS iso-conversional method, which was further exploited to estimate the thermodynamic parameters, nucleation rate, and interfacial energy of ∼1 nm-sized gadolinium nanoclusters, in the temperature ranging from 555 to 780 K by appraising thermogravimetric data. The obtained Z (α) master plot suggested the existence of random nucleation within the BSA matrix of Gd2O3 nanoclusters at high temperatures over a specified conversion value. Additionally, four mathematical models were proposed using the above finding to interpret the nucleation rate and interfacial energy concerning high temperature and specified conversion points for the first time.

A New Technique for Calculating Kinetic and Thermodynamic Barriers for Nucleation Rates and Interfacial Energy of CaCO3 Prenucleation Nanoclusters at High Temperature Using TGA Models and In Situ Crystallization

Abstract: Nucleation at different temperature levels can provide quantitative insights into the energy barrier associated with sub‐molecular nuclei. The accurate calculation of nucleation rates, thermodynamics, and interfacial energy for extremely small nanoclusters (1−2 nm) remains a challenge at high temperatures. Here, Eα${E}_{\alpha}$ , ΔG,ΔH,ΔSandAα$\Delta G,\Delta H,\Delta S\ \mathrm{and}\ {A}_{\alpha}$ are computed to estimate the nucleation rate of ultra‐small CaCO3 pre‐nucleation clusters (0.85 nm) from thermogravimetric analysis (TGA) experimental values in the temperature range from 555 to 795 K, by adopting the most accurate iterative iso‐conversional method and random nucleation dependent differential function f(α)$f(\alpha )$ , respectively. On the basis of these analyses, four mathematical models are presented for computing nucleation rates (nucleiμm−2min−1)$(\mathrm{nuclei}\ \umu{\mathrm{m}}^{-2}\,{\min}^{-1})$ and interfacial energy (mJ m−2 variation with temperature and conversion for CaCO3 prenucleation clusters. Furthermore, experimental validation is also carried out in order to assess the existence of nucleation in CaCO3 pre‐nucleation clusters at high temperatures (500 °C) using X‐ray diffraction and experimental z(α) master plots. The TGA can be used to predict and understand nucleation rates for various nano systems.