Ultrafast dynamics of excitons in semiconductor quantum dots on a plasmonically active nano-structured silver film

The excited state dynamics of core-shell type semiconductor quantum dots (QDs) of various sizes in close contact with a plasmonically active silver thin film has been demonstrated by using picosecond resolved fluorescence spectroscopy. The non-radiative energy transfer from the QDs to the metal surface is found to be of Föster resonance energy transfer (FRET) type rather than the widely expected nano-surface energy transfer (NSET) type. The slower rate of energy transfer processes compared to that of the electron transfer from the excited QDs to an organic molecule benzoquinone reveals an insignificant possibility of charge migration from the QDs to the metallic film

ANATOMY AND MICROSCOPICAL STUDIES ON THYMUS OF A LARVIVOROUS FISH [APLOCHEILUS PANCHAX (HAMILTON, 1822)]

ABSTRACT The macro and microanatomy of thymus gland in Aplocheilus panchax (Hamilton, 1822) [a larvivorous fish] belonging to the Order: Cyprinidontiformes has been studied under light microscope (LM), scanning and transmission electron microscope (SEM + TEM) respectively. A. panchax possess apparently triangular shaped thymus gland which is located within the branchial cavity at the base of third and fourth gill arches. The surface structure of thymus gland shows numerous pores of varying diameter (0.75μm. to 1.5μm.) under scanning electron microscope (SEM). Microanatomically, the thymus is not well demarcated into cortex and medulla. This gland is composed of different types of lymphoid and non-lymphoid cellular components. The thymic epithelial cells and thymic trabeculae are also identified. The heterogeneity of thymic cells is need to further study for exploring the multifunctional aspects of this concerned lymphoid organ as a whole

A study on association between non alcoholic fatty liver disease and ischemic heart disease in a tertiary care hospital

Background: Non-alcoholic fatty liver disease (NAFLD) is often an incidental finding in a large subset of Indian population, who because of their sedentary life style are more prone to ischaemic heart disease (IHD). This study was aimed at determining the association between NAFLD and IHD, with and without traditional risk factors for ischemic heart disease and to determine the relationship between the ischemic heart disease and severity of NAFLD. Materials and methods: It was a prospective comparative study among patients who got admitted in General Medicine ward or visited OPD of our institute from February 2020 to September 2021. Patients selected were divided into two groups- Study arm included patients with clinical features and investigations suggestive of ischemic heart disease. Control arm patients were age (+/-5years) matched people coming to hospital with infections/ illness not affecting liver, and without any history of ischaemic heart disease. We did check for NAFLD in these patients and tried to determine the association with IHD. Results: Significant number of patients (68.5%) had NAFLD in the study arm patients who were admitted for IHD in comparison to only 33.3% (p value-<0.001). Study arm had 31% patients with grade 2 or more NAFLD in comparison to 17% of control arm patients. There was significant association present between IHD and Severity of NAFLD (p value<0.05). Conclusion: NAFLD should be considered a risk factor of IHD, and should prompt clinicians to search for other cardiovascular risk factors and intervene at earliest

Design and Analysis of an AC Coupled Photovoltaic System for an Off-grid Community in Chittagong Hill Tracts

This paper presents the design of an AC-coupled off-grid photovoltaic (PV) system for a remote village in the Chittagong Hill Tracts of Bangladesh which has no access to national utility grid. A field survey was conducted to collect load demand data of the population for designing an optimal PV system architecture to serve that community. The proposed system consists of 18 kW PV arrays, two 6 kW grid-tied inverters, a 6 kW battery inverter and a 19.2 kWh nominal capacity battery bank. Further, the technical feasibility of the system was evaluated using HOMER (Hybrid Optimization Model for Electric Renewable) Pro software. The analytical results indicate that the proposed AC-coupled stand-alone solar system can meet a load demand of 46.58 kWh at daytime and 7.02 kWh at night in that village. Currently, the infrastructure of proposed PV plant as well as the transmission and distribution network are being developed at the selected site. Moreover, insights into the benefits of AC-coupling over DC-coupling for large off-grid systems in remote hilly areas are provided in the paper

Mathematical model of COREX melter gasifier: Part II. Dynamic model

A dynamic model of the COREX melter gasifier is developed to study the transient behavior of the furnace. The effect of pulse disturbance and step disturbance on the process performance has been studied. This study shows that the effect of pulse disturbance decays asymptotically. The step change brings the system to a new steady state after a delay of about 5 hours. The dynamic behavior of the melter gasifier with respect to a shutdown/blow-on condition and the effect of tapping are also studied. The results show that the time response of the melter gasifier is much less than that of a blast furnace

A Study on Heart Failure with Preserved Ejection Fraction among Patients of Type 2 Diabetes Mellitus in a Tertiary Care Hospital, India

Introduction: Diabetes is associated with several diabetic-related abnormalities and increased retention of sodium (up regulation of sodium-glucose co transporters) which increases the risk of onset or worsening of heart failure. With this background, the current study was planned to study the prevalence of type 2 diabetes mellitus among patients presenting with heart failure with preserved ejection fraction. Materials and Methods: It was a prospective observational study among patients visiting outpatient department and IPD of Nil Ratan Sircar Medical College &amp; Hospital, India from October 2016 to September 2017. The study was pre-approved by Institutional Ethics Committee and the study was conducted after obtaining permission accordingly. Sample size was 100 patients between 30 and 90 years both male and female. The patients who satisfied inclusion and exclusion criteria have been identified and included in this study. Quantitative data thus obtained have been analyzed and exported to statistical software SPSS ver. 20.0. The continuous variables have been presented as mean ± standard deviation. Results: A total of 100 patients between 30 and 90 years, both male and female who met the inclusion criteria were selected for the study. Majority belonged to the age group of 61–70 years with mean age 63.5 ±7.2 years. 53 were men and 47 were female. Diabetes was present in 51 patients. Majority had ejection fraction between 55 and 60% and mean was 57.3± 6.7%; mostly with normal or near normal systolic function. The elevated mean LVMI indicated LV hypertrophy and decreased mean E/A indicated LV diastolic dysfunction, often produced by diabetes. Mean E/E’ was 9.2 ± 5.4. Grade-2 (DD2) diastolic dysfunction patients were maximum in number comprising 47% followed by Grade-1 (DD1) diastolic dysfunction among 44%, and only 9% had Grade-3 (DD3) diastolic dysfunction. Conclusion: Etiology and treatment approach of HFpEF differs from that of HFrEF. Moreover, diabetes mellitus is the modern day epidemics. Hence, if further studied by multicenter, prospective, longitudinal studies, this association may be used to identify the population at risk

Inhibition of catalase by tea catechins in free and cellular state: a biophysical approach.

Tea flavonoids bind to variety of enzymes and inhibit their activities. In the present study, binding and inhibition of catalase activity by catechins with respect to their structure-affinity relationship has been elucidated. Fluorimetrically determined binding constants for (-)-epigallocatechin gallate (EGCG) and (-)-epicatechin gallate (ECG) with catalase were observed to be 2.27×106 M(-1) and 1.66×106 M(-1), respectively. Thermodynamic parameters evidence exothermic and spontaneous interaction between catechins and catalase. Major forces of interaction are suggested to be through hydrogen bonding along with electrostatic contributions and conformational changes. Distinct loss of α-helical structure of catalase by interaction with EGCG was captured in circular dichroism (CD) spectra. Gallated catechins demonstrated higher binding constants and inhibition efficacy than non-gallated catechins. EGCG exhibited maximum inhibition of pure catalase. It also inhibited cellular catalase in K562 cancer cells with significant increase in cellular ROS and suppression of cell viability (IC50 54.5 µM). These results decipher the molecular mechanism by which tea catechins interact with catalase and highlight the potential of gallated catechin like EGCG as an anticancer drug. EGCG may have other non-specific targets in the cell, but its anticancer property is mainly defined by ROS accumulation due to catalase inhibition