Room-temperature response of MOF-derived Pd@PdO core shell/γ-Fe2O3 microcubes decorated graphitic carbon based ultrasensitive and highly selective H2 gas sensor.

With the current upsurge in hydrogen economies all over the world, an increased demand for improved chemiresistive H2 sensors that are highly responsive and fast acting when exposed to gases is expected. Owing to safety concerns about explosive and highly flammable H2 gas, it is important to develop resistive sensors that can detect the leakage of H2 gas swiftly and selectively. Currently, interest in metal-organic frameworks (MOFs) for gas-sensor applications is increasing due to their open-metal sites, large surface area, and unique surface morphologies. In this research, a highly selective and sensitive H2-sensor was established based on graphitic carbon (GC) anchored spherical Pd@PdO core-shells over γ-Fe2O3 microcube (Pd@PdO/γ-Fe2O3@GC which is termed as S3) heterostructure materials. The combined solvothermal followed by controlled calcination-assisted S3 exhibited a specific morphology with the highest surface area of 79.12 m2 g-1, resulting in fast response and recovery times (21 and 29 s, respectively), and excellent sensing performance (ΔR/R0∼ 96.2 ± 1.5), outstanding long-term stability, and a 100 ppb detection limit when detecting H2-gas at room temperature (mainly in very humid surroundings). This result proves that adsorption sites provided by S3 can promote surface reactions (adsorption and desorption) for ultrasensitive and selective H2gas sensors.

Ternary Zn1-xNixSe nanostructures as efficient photocatalysts for detoxification of hazardous Congo red, methyl orange, and chrome yellow dyes in wastewater sources.

Water contamination by hazardous organic pollutants poses an extreme threat to the environment and globally endangers aquatic life and human health. Hence, the removal of toxic organic effluents from water sources is necessary to ensure a healthy green environment. To this end, a new class of emerging, visible-light-driven Zn- and Ni-based ternary metal-selenide (Zn1-xNixSe) nanophotocatalysts, with tunable nanostructures via regulation of the stoichiometric ratios of Zn and Ni, were synthesized for efficient water purification by a facile one-pot hydrothermal process. These catalysts exhibit outstanding porous properties, with large surface areas and average particle sizes of around 80 ± 10 nm. The as-prepared ternary Zn1-xNixSe catalysts enable improved optical properties, intrinsic conductivity, bandgap reductions, and large numbers of active sites compared with pristine materials, thereby exhibiting outstanding degradation properties against various dye molecules, including Congo red, methyl orange, and chrome-IV upon visible light irradiation. The improved photodegradation capabilities of the Zn1-xNixSe catalysts may be attributed to the synergistic combinations of Zn and Ni selenides, which in turn minimize the recombination rates of the photogenerated carriers compared to their individual constituents. These findings clearly demonstrate that the proposed ternary Zn1-xNixSe catalysts could be potentially used to remove toxic organic contaminants from industrial wastewater.

Evaluation of Leptin as a Marker of Insulin Resistance in Type 2 Diabetes Mellitus.

BACKGROUND: Type 2 diabetes mellitus (T2DM) is a leading cause of mortality and morbidity worldwide, whose incidence is rapidly increasing in India. T2DM is caused by varying degrees of insulin resistance (IR) and relative insulin deficiency. Leptin, an adipokine with the primary function of regulating energy balance, is found to mediate insulin secretion and sensitivity in peripheral tissues. Hence, we aimed to determine the role of leptin in the development of IR in newly diagnosed T2DM patients. AIM: This study aims to compare the leptin levels and homeostatic model assessment-IR (HOMA-IR) levels in the study population. MATERIAL AND METHODS: The study included a total of sixty patients newly diagnosed with T2DM. Their fasting blood samples were collected to estimate the glucose, insulin, and leptin levels. IR was calculated using HOMA-IR formula. Statistical analysis was done by Pearson's correlation, Spearman's correlation, and One-sample Wilcoxon Signed Rank test. RESULTS: Leptin and HOMA-IR levels were significantly high in T2DM patients (P < 0.001) when compared with reference values. Body mass index showed a significant positive correlations with insulin (r = 0.40, P < 0.01), HOMA-IR (r = 0.37, P < 0.01), and leptin levels (r = 0.90, P < 0.01). Leptin levels showed significant positive correlations with plasma insulin (r = 0.35, P < 0.01) and HOMA-IR levels (r = 0.31, P < 0.05). The correlation between leptin and HOMA-IR levels was more pronounced and significant among the obese T2DM subjects (r = 0.82, P = 0.01). CONCLUSION: Hyperleptinemia reflecting leptin resistance plays an important role in the development of IR in obeseT2DM patients, making leptin a possible biomarker for the same.