Banaras Hindu University

About: Banaras Hindu University is a education organization based out in Varanasi, Uttar Pradesh, India. It is known for research contribution in the topics: Population & Dielectric. The organization has 11858 authors who have published 23917 publications receiving 464677 citations. The organization is also known as: Kashi Hindu Vishvavidyalay & Benares Hindu University.

Microwave Assisted Extraction-An Innovative and Promising Extraction Tool for Medicinal Plant Research

Abstract: In recent years, the use of microwave for extraction of constituents from plant material has shown tremendous research interest and potential. Conventional techniques for the extraction of active constituents are time and solvent consuming, thermally unsafe and the analysis of numerous constituents in plant material is limited by the extraction step. This review highlights the importance of extraction step in setting up respectable standards for herbal medicine worldwide. High and fast extraction performance ability with less solvent consumption and protection offered to thermolabile constituents are some of the attractive features of this new promising microwave assisted extraction (MAE) technique. A brief theoretical background of microwave heating and the basic principles of using microwave energy for extraction have been presented for better understanding. Discussions on the main parameters influencing the extraction efficiency (namely solvent nature and volume, extraction time, microwave power, matrix characteristics and temperature) and different statistical optimization strategies are also highlighted. Finally the potential applications of this new method with comparison of its performance to that of classical techniques are also elucidated.

Carbon nanotube filters.

Abstract: Over the past decade of nanotube research, a variety of organized nanotube architectures have been fabricated using chemical vapour deposition. The idea of using nanotube structures in separation technology has been proposed, but building macroscopic structures that have controlled geometric shapes, density and dimensions for specific applications still remains a challenge. Here we report the fabrication of freestanding monolithic uniform macroscopic hollow cylinders having radially aligned carbon nanotube walls, with diameters and lengths up to several centimetres. These cylindrical membranes are used as filters to demonstrate their utility in two important settings: the elimination of multiple components of heavy hydrocarbons from petroleum-a crucial step in post-distillation of crude oil-with a single-step filtering process, and the filtration of bacterial contaminants such as Escherichia coli or the nanometre-sized poliovirus ( approximately 25 nm) from water. These macro filters can be cleaned for repeated filtration through ultrasonication and autoclaving. The exceptional thermal and mechanical stability of nanotubes, and the high surface area, ease and cost-effective fabrication of the nanotube membranes may allow them to compete with ceramic- and polymer-based separation membranes used commercially.

Elliptic flow of identified hadrons in [formula presented] collisions at [formula presented]

Abstract: The anisotropy parameter (v(2)), the second harmonic of the azimuthal particle distribution, has been measured with the PHENIX detector in Au+Au collisions at roots(NN)=200 GeV for identified and inclusive charged particle production at central rapidities (eta 2 GeV/c, in marked contrast to the predictions of a hydrodynamical model. A quark-coalescence model is also investigated.

Drug resistance in Indian visceral leishmaniasis.

Abstract: Throughout the world, pentavalent antimonial compounds (Sb(v)) have been the mainstay of antileishmanial therapy for more than 50 years. Sb(v) has been highly effective in the treatment of Indian visceral leishmaniasis (VL: kala-azar) at a low dose (10 mg/kg) for short durations (6-10 days). But in the early 1980s reports of its ineffectiveness emerged, and the dose of Sb(v) was eventually raised to 20 mg/kg for 30-40 days. This regimen cures most patients with VL except in India, where the proportion of patients unresponsive to Sb(v) has steadily increased. In hyperendemic districts of north Bihar, 50-65% patients fail treatment with Sb(v). Important reasons are rampant use of subtherapeutic doses, incomplete duration of treatment and substandard drugs. In vitro experiments have established emergence of Sb(v) resistant strains of Leishmania donovani, as isolates from unresponsive patients require 3-5 times more Sb(v) to reach similarly effectiveness against the parasite as in Sb(v) responders. Anthroponotic transmission in India has been an important factor in rapid increase in the Sb(v) refractoriness. Pentamidine was the first drug to be used and cured 99% of these refractory patients, but over time even with double the amount of initial doses, it cures only 69-78% patients now and its use has largely been abandoned in India. Despite several disadvantages, amphotericin B is the only drug available for use in these areas and should be used as first-line drug instead of Sb(v). The new oral antileishmanial drug miltefosine is likely to be the first-line drug in future. Unfortunately, development of newer antileishmanial drugs is rare; two promising drugs, aminosidine and sitamaquine, may be developed for use in the treatment of VL. Lipid associated amphotericin B has an excellent safety and efficacy profile, but remains out of reach for most patients because of its high cost.