Emergence of Ni-Based Chalcogenides (S and Se) for Clean Energy Conversion and Storage.

Nickel chalcogenide (S and Se) based nanostructures intrigued scientists for some time as materials for energy conversion and storage systems. Interest in these materials is due to their good electrochemical stability, eco-friendly nature, and low cost. The present review compiles recent progress in the area of nickel-(S and Se)-based materials by providing a comprehensive summary of their structural and chemical features and performance. Improving properties of the materials, such as electrical conductivity and surface characteristics (surface area and morphology), through strategies like nano-structuring and hybridization, are systematically discussed. The interaction of the materials with electrolytes, other electro-active materials, and inactive components are analyzed to understand their effects on the performance of energy conversion and storage devices. Finally, outstanding challenges and possible solutions are briefly presented with some perspectives toward the future development of these materials for energy-oriented devices with high performance.

Extrinsic Pseudocapacitive NiSe/rGO/g-C3N4 Nanocomposite for High-Performance Hybrid Supercapacitors.

Battery-type materials with ultrahigh energy density show great potential for hybrid supercapacitors (HSCs). In this work, we have developed a nickel selenide (NiSe)/reduced graphene oxide (rGO)/graphitic carbon nitride (g-C3N4) ternary composite as a promising positive electrode for hybrid supercapacitors (HSCs). The extended π-conjugated planar layers of g-C3N4 promote strong interconnectivity with rGO, which further enhances surface area, surface free energy, and efficient electron/ionic path. Additionally, it establishes clear ion diffusion pathways, serving as ion reservoirs during charge and discharge and facilitating efficient redox reactions. As a result, the NiSe/g-C3N4/rGO nanocomposite electrode displayed a specific capacity of 412.6 mA h g-1 at 1 A g-1. Later, the HSC device was assembled using the nanocomposite as the positive electrode and activated carbon as the negative electrode, which delivered an energy density of 65.2 Wh kg-1 at a power density of 750 W kg-1. Notably, the HSC device maintained excellent cyclic stability, preserving 93.3% of its initial performance and Coulombic efficiency of 86.6% for 10,000 charge-discharge cycles at 5 A g-1. These findings underscore the potential utility of NiSe/g-C3N4/rGO as a versatile and effective electrode material for the strategic development of HSC devices.

Pulsed plasma polymerization for controlling shrinkage and surface composition of nanopores.

Solid-state nanopores have emerged as sensors for single molecules and these have been employed to examine the biophysical properties of an increasingly large variety of biomolecules. Herein we describe a novel and facile approach to precisely adjust the pore size, while simultaneously controlling the surface chemical composition of the solid-state nanopores. Specifically, nanopores fabricated using standard ion beam technology are shrunk to the requisite molecular dimensions via the deposition of highly conformal pulsed plasma generated thin polymeric films. The plasma treatment process provides accurate control of the pore size as the conformal film deposition depends linearly on the deposition time. Simultaneously, the pore and channel chemical compositions are controlled by appropriate selection of the gaseous monomer and plasma conditions employed in the deposition of the polymer films. The controlled pore shrinkage is characterized with high resolution AFM, and the film chemistry of the plasma generated polymers is analyzed with FTIR and XPS. The stability and practical utility of this new approach is demonstrated by successful single molecule sensing of double-stranded DNA. The process offers a viable new advance in the fabrication of tailored nanopores, in terms of both the pore size and surface composition, for usage in a wide range of emerging applications.

Non-thermal Technologies for Food Processing.

Food is subjected to various thermal treatments during processes to enhance its shelf-life. But these thermal treatments may result in deterioration of the nutritional and sensory qualities of food. With the change in the lifestyle of people around the globe, their food needs have changed as well. Today's consumer demand is for clean and safe food without compromising the nutritional and sensory qualities of food. This directed the attention of food professionals toward the development of non-thermal technologies that are green, safe, and environment-friendly. In non-thermal processing, food is processed at near room temperature, so there is no damage to food because heat-sensitive nutritious materials are intact in the food, contrary to thermal processing of food. These non-thermal technologies can be utilized for treating all kinds of food like fruits, vegetables, pulses, spices, meat, fish, etc. Non-thermal technologies have emerged largely in the last few decades in food sector.

Pulsed plasma surface functionalized nanosilver for gene delivery.

Lack of suitable surface properties in biomaterials is an acute challenge for their utilization in nucleic acid delivery, since surface plays a vital role in cell adhesion/uptake and immunity. Low pressure cold plasma is a promising technology for functionalization and surface modification of materials, in an effective, environment friendly and economical way. In this investigation we have modified the surface of silver nanoparticles (AgNPs) with chitosan biopolymer, using plasma treatment, to extend their application scope in intracellular DNA delivery. The plasma functionalized; chitosan modified AgNPs (MetaloPolymeric Nanocarriers; MPNCs) possessed superior biocompatibility compared to unmodified AgNPs. Carboxylic groups were incorporated on the surface of nanosilver using 3600 rotating pulsed plasma reactor and acrylic acid vapors were used as precursor gas. Pulsed plasma polymerization process was optimized with respect to working pressure of the system, duty cycle for pulsing, time of treatment and flow rate. Biocompatibility of the plasma functionalized nanosilver was enhanced by coupling it with Chitosan Oligosaccharide (COS), using EDC (1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide) to form amide linkages. The resulting MPNCs showed high cell viability and bio-stability, which was attributed to plasma processing of nanosilver and its association with COS. In vitro cellular studies illustrated significant uptake of nanoplexes. The study suggested the potential of plasma functionalization for manipulating surfaces of metallic nanoparticles to enhance their application in intracellular gene delivery.

Influence of intrinsic myocardial conduction on paced QRS morphology during cardiac resynchronization therapy follow up.

We report two cases of patients of cardiac resynchronization therapy (CRT) whose ECGs, during follow up, showed different paced QRS morphology as compared to those of immediate post-device implantation. Parameters of leads, including sensitivity and capture thresholds, were unchanged. There was no lead dislodgement confirmed on fluoroscopy. The ECGs obtained in device off mode showed different intrinsic QRS morphology as compared to those of pre-implant morphology. These changes were attributable to electrolyte imbalance in one patient and progressive intraventricular conduction defect in the other. These cases demonstrate that intrinsic myocardial conduction pattern influences paced QRS morphology. Irreversible change in paced QRS morphology may indicate poor prognosis.

Risk scoring system to predict contrast induced nephropathy following percutaneous coronary intervention.

BACKGROUND: Contrast induced nephropathy (CIN) is associated with significant morbidity and mortality after percutaneous coronary intervention (PCI). The aim of this study is to evaluate the collective probability of CIN in Indian population by developing a scoring system of several identified risk factors in patients undergoing PCI. METHODS: This is a prospective single center study of 1200 consecutive patients who underwent PCI from 2008 to 2011. Patients were randomized in 3:1 ratio into development (n = 900) and validation (n = 300) groups. CIN was defined as an increase of ≥25% and/or ≥0.5 mg/dl in serum creatinine at 48 hours after PCI when compared to baseline value. Seven independent predictors of CIN were identified using logistic regression analysis - amount of contrast, diabetes with microangiopathy, hypotension, peripheral vascular disease, albuminuria, glomerular filtration rate (GFR) and anemia. A formula was then developed to identify the probability of CIN using the logistic regression equation. RESULTS: The mean (±SD) age was 57.3 (±10.2) years. 83.6% were males. The total incidence of CIN was 9.7% in the development group. The total risk of renal replacement therapy in the study group is 1.1%. Mortality is 0.5%. The risk scoring model correlated well in the validation group (incidence of CIN was 8.7%, sensitivity 92.3%, specificity 82.1%, c statistic 0.95). CONCLUSION: A simple risk scoring equation can be employed to predict the probability of CIN following PCI, applying it to each individual. More vigilant preventive measures can be applied to the high risk candidates.

Surface chemistry and polymer film thickness effects on endothelial cell adhesion and proliferation.

Adherence and growth rates of human aortic endothelial cells (HAEC) on plasma polymerized poly(vinylacetic acid) films were measured as functions of the surface density of --COOH groups and plasma deposited film thickness. Pulsed plasma polymerization was employed to produce films containing 3.6 to 9% --COOH groups, expressed as a percent of total carbon content. Endothelial cells exhibited increased cell adherence and proliferation with increasing --COOH surface densities. Additionally, and unexpectedly, cell growth was also dependent on the film thicknesses, which ranged from 25 to 200 nm. The results indicate that optimization of the functional group surface density and film thickness could produce significant enhancements in initial adhesion and subsequent growth of the HAEC cells.