Flash X Ray: A Diagnostic Tool for Shaped Charge Studies

At present many antitank weapon systems are employing shaped charge warheads. It is, therefore, extremely important for a designer to avail of the methods capable of predicting performance of shaped charges, mainly to achieve maximum penetration. For this purpose, it is necessary to study the behaviour of the shaped charge during actual firing tests. These tests are difficult because of high speed of events that take place, production of intense light, smoke, debris, etc, and the large scale destruction caused. To overcome these difficulties, flash x-ray system during the jet studies on 30, 60 and 90 mm shaped charges and the evaluation of jet characteristics parameters

Network Planning Tool for Ka-Band Terrestrial Wireless and Broadband LEO Networks

Technologies capable of providing high data rates have a lot of business potential. Comprehensive planning goes behind setting up networks for service provision. It is necessary to consider alternative techniques of service provision and market characteristics before designing the network. We prepare an optimization tool to aid business analysts in designing networks for selected markets. It compares the performance expected of LMDS, Broadband LEO and Fiber Optic networks.Characteristics of each technology make it suitable for markets with certain characteristics, and unsuitable for some. A Geographical Information System and a mathematical programming package are integrated to form a tool which writes algorithms for selected regions for each technology. They are optimized to predict performance of each technology in the form of cost versus performance tradeoffs. Using these results, the analyst can design an optimum network

Modelling of a Regenerative Liquid Propellant Gun

In the development of liquid propellant guns (LPG), there are numerous interdependent parameters which affect the performance of the gun. There are some difficulties in arriving at the dimensions of its various components. To help in this task, computer simulation was undertaken to predict the performance of a conceptual gun. This is a sensitivity study aimed at exploring the relationship between the interdependent parameters. The parameters which have a direct bearing on the performance of the gun, like areas of cross-section of vents, differential piston dimensions liquid propellant mass, and the combustion and reservoir chamber dimensions have been studied. The expected pressures and other parameters could be studied with the help of this model is thus helpful in the optimization of the design of LPGs

Prospect of nanomaterials as antimicrobial and antiviral regimen

In recent years studies of nanomaterials have been explored in the field of microbiology due to the increasing evidence of antibiotic resistance. Nanomaterials could be inorganic or organic, and they may be synthesized from natural products from plant or animal origin. The therapeutic applications of nano-materials are wide, from diagnosis of disease to targeted delivery of drugs. Broad-spectrum antiviral and antimicrobial activities of nanoparticles are also well evident. The ratio of nanoparticles surface area to their volume is high and that allows them to be an advantageous vehicle of drugs in many respects. Effective uses of various materials for the synthesis of nanoparticles impart much specificity in them to meet the requirements of specific therapeutic strategies. The potential therapeutic use of nanoparticles and their mechanisms of action against infections from bacteria, fungi and viruses were the focus of this review. Further, their potential advantages, drawbacks, limitations and side effects are also included here. Researchers are characterizing the exposure pathways of nano-medicines that may cause serious toxicity to the subjects or the environment. Indeed, societal ethical issues in using nano-medicines pose a serious question to scientists beyond anything

Modelling and Simulation of a Railgun powered by a Capacitor Bank

A railgun powered by a capacitor bank was developed to launch hypervelocity projectiles. The efficiency of the gun to a large extent will determine its feasibility for weapon applications. A simulation code was developed to predict the performance of the railgun. The railgun has been modelled as a time-varying impedance to determine the currents and the voltages from the power source. In the railgun circuit the currents and the voltages are of the order of hundreds of kiloamperes. Even very low impedances of the order of milli-ohm and micro-henry are substantial sources of energy losses. The measured and simulation currents at peak values agree with in 10%, validating the model. The simulation code accurately predicts the energy distribution in the system. Maximization of the projectile energy leads to improved and efficient designs. The simulation also leads to the optimized launcher pressure and payload velocity

Low-Cost Production of Proinsulin in Tobacco and Lettuce Chloroplasts for Injectable or Oral Delivery of Functional Insulin and C-Peptide

Current treatment for type I diabetes includes delivery of insulin via injection or pump, which is highly invasive and expensive. The production of chloroplast-derived proinsulin should reduce cost and facilitate oral delivery. Therefore, tobacco and lettuce chloroplasts were transformed with the cholera toxin B subunit fused with human proinsulin (A, B, C peptides) containing three furin cleavage sites (CTB-PFx3). Transplastomic lines were confirmed for site-specific integration of transgene and homoplasmy. Old tobacco leaves accumulated proinsulin up to 47% of total leaf protein (TLP). Old lettuce leaves accumulated proinsulin up to 53% TLP. Accumulation was so stable that up to ~40% proinsulin in TLP was observed even in senescent and dried lettuce leaves, facilitating their processing and storage in the field. Based on the yield of only monomers and dimers of proinsulin (3 mg/g leaf, a significant underestimation), with a 50% loss of protein during the purification process, one acre of tobacco could yield up to 20 million daily doses of insulin per year. Proinsulin from tobacco leaves was purified up to 98% using metal affinity chromatography without any His-tag. Furin protease cleaved insulin peptides in vitro. Oral delivery of unprocessed proinsulin bioencapsulated in plant cells or injectable delivery into mice showed reduction in blood glucose levels similar to processed commercial insulin. C-peptide should aid in long-term treatment of diabetic complications including stimulation of nerve and renal functions. Hyper-expression of functional proinsulin and exceptional stability in dehydrated leaves offer a low-cost platform for oral and injectable delivery of cleavable proinsulin

The role of ERK5 in endothelial cell function

Extracellular-signal-regulated kinase 5 (ERK5), also termed big MAPK1 (BMK1), is the most recently discovered member of the mitogen-activated protein kinase (MAPK) family. It is expressed in a variety of tissues and is activated by a range of growth factors, cytokines and cellular stresses. Targeted deletion of Erk5 in mice has revealed that the ERK5 signalling cascade is critical for normal cardiovascular development and vascular integrity. In vitro studies have revealed that, in endothelial cells, ERK5 is required for preventing apoptosis, mediating shear-stress signalling and regulating tumour angiogenesis. The present review focuses on our current understanding of the role of ERK5 in regulating endothelial cell function