LCC resonant converter with power factor correction for power supply units

This article presents a power supply using an LCC resonant converter having power factor correction with burst mode operation. In order to improve the performance from no load to full load, a microcontroller with an active control has been introduced. The light load efficiency is increased using burst mode operation. The proposed controller provides zero voltage switching. Mathematical analysis is done, and steady state characteristics are drawn. A simple design example is given based on the equations. The proposed converter has good efficiency with good power factor at all loading conditions. This is shown by the simulation and experimental results obtained through testing the prototype.     

Standalone PV-fed LED Street Lighting Using Resonant Converter

This paper proposes a single-stage, single-switch, non-isolated step-up converter with resonant inverter for a standalone photovoltaic battery-powered light-emitting diode (LED) street light. The LED driver presented in this paper integrates a high step-up DC–DC converter with coupled inductors and LCC resonant converter into a single-stage conversion circuit topology. The proposed converter is a compact cost-effective driver for powering a 60 W LED Street light with a battery backup charged from PV array of 12 V. The modes of operation and analysis of the proposed converter are explained. The design of the circuit elements is done based on the theoretical analysis. The proposed circuit has been simulated, and prototype has been developed to demonstrate its feasibility.     

Apolipoprotein E in Cardiometabolic and Neurological Health and Diseases

A preponderance of evidence obtained from genetically modified mice and human population studies reveals the association of apolipoprotein E (apoE) deficiency and polymorphisms with pathogenesis of numerous chronic diseases, including atherosclerosis, obesity/diabetes, and Alzheimer’s disease. The human APOE gene is polymorphic with three major alleles, ε2, ε3 and ε4, encoding apoE2, apoE3, and apoE4, respectively. The APOE gene is expressed in many cell types, including hepatocytes, adipocytes, immune cells of the myeloid lineage, vascular smooth muscle cells, and in the brain. ApoE is present in subclasses of plasma lipoproteins, and it mediates the clearance of atherogenic lipoproteins from plasma circulation via its interaction with LDL receptor family proteins and heparan sulfate proteoglycans. Extracellular apoE also interacts with cell surface receptors and confers signaling events for cell regulation, while apoE expressed endogenously in various cell types regulates cell functions via autocrine and paracrine mechanisms. This review article focuses on lipoprotein transport-dependent and -independent mechanisms by which apoE deficiency or polymorphisms contribute to cardiovascular disease, metabolic disease, and neurological disorders.     

Seaweed sap: a sustainable way to improve productivity of maize in North-East India

The average productivity of Maize in the north-east hill region of India is very low (1.50 t/ha) mainly owing to cultivation under nutrient-starved conditions. Practical technologies have been developed to cultivate two commercially important seaweeds, viz. Kappaphycus alvarezii and Gracilaria edulis in tropical waters. The sap of these seaweeds has turned out to be a low-cost potent plant biostimulant when applied as foliar spray. A field experiment was conducted using different concentrations of both the seaweed saps in a research farm at Umiam, Meghalaya to study their impact on growth, yield and quality of maize. Results indicated that both the seaweed saps significantly improved the grain yield (10.5–13.1%), carbohydrate (12.3–17.4%) and protein content (4.8%) of maize over and above the control which received the recommended dose of fertilizers only. Thus, these seaweed saps are proved to be an eco-friendly means for enhancing maize productivity and quality in this economically backward region.