Some theorems on stability of discrete circulatory systems

Stability theorems established for static and dynamic losses in discrete, linear, elastic system

Destabilizing effect of velocity-dependent forces in nonconservative continuous systems Technical report no. 65-4

Velocity dependent force destabilizing effect in cantilevered continuous pipe conveying fluid at constant velocit

A Study on Impact Resistance of Glass Fibre Reinforced Vinylester Composites against ballistic Projectiles

Glass fibre reinforced vinylester laminates show very high impact resistance, the charpy impact strength measuring upto 576 kJ/m'. Void-free laminates prepared from E-glass fibre-reinforcement and vinylester resin. matrix combined with resin bonded alumina sheets as facing have been subjected to high velocity impact of 7.62 mm bullets fired from a distance of 10 meters. Glass fibre and Kevlar-29 fibre reinforced vinylester laminates with a thickness less than 10 mm (areal density - 14.24 kg/ 111'.) have been tested against 1.1 g fragment simulated projectiles (FSP) in the form of steel balls and 9 mm carbine fire. The laminates thus tested withstood the bullets without any bulge at the back. The possible mechanism of the hyper velocity impact resistance of the FRP laminates has been discussed

What have two decades of laboratory life-history evolution studies on Drosophila melanogaster taught us?

A series of laboratory selection experiments on Drosophila melanogaster over the past two decades has provided insights into the specifics of life-history tradeoffs in the species and greatly refined our understanding of how ecology and genetics interact in life-history evolution. Much of what has been learnt from these studies about the subtlety of the microevolutionary process also has significant implications for experimental design and inference in organismal biology beyond life-history evolution, as well as for studies of evolution in the wild. Here we review work on the ecology and evolution of life-histories in laboratory populations of D. melanogaster, emphasizing how environmental effects on life-history-related traits can influence evolutionary change. We discuss life-history tradeoffs-many unexpected-revealed by selection experiments, and also highlight recent work that underscores the importance to life-history evolution of cross-generation and cross-life-stage effects and interactions, sexual antagonism and sexual dimorphism, population dynamics, and the possible role of biological clocks in timing life-history events. Finally, we discuss some of the limitations of typical selection experiments, and how these limitations might be transcended in the future by a combination of more elaborate and realistic selection experiments, developmental evolutionary biology, and the emerging discipline of phenomics

Efficacy of bipolar hemiarthroplasty in the elderly people: a study in a tertiary care centre

Background: Intertrochanteric fractures are associated with severe displacement and comminution are very common among the elderly patients especially women. Hemiarthroplasty is a procedure, where the head of the femur is replaced with a prosthetic implant. This study was performed to evaluate the efficacy of the bipolar hemiarthroplasty among the elderly patients with intra capsular fractures.Methods: Bipolar hemiarthroplasty with or without cement was performed on 77 patients above the age of 60 years with femoral neck fractures.Results: Out of the 77 patients, 79.2% were females and 20.8% were males. The mean age of all the patients was 68.4 years. Type IV was found to be most common among the elderly. The outcome of the surgery was excellent in more than 75% of the cases. Only one patient had a poor outcome. The most common complication of the surgery was limb shortening in 5.2% patients followed by superficial infections in 2.6%. Conclusions: Bipolar hemiarthroplasty for the unstable hip fractures in the elderly has good results with early mobilizations and minimal complications. This ultimately affects the general health of the patients and reduces morbidity and mortality

Treatment of open tibial shaft fractures using intra medullary interlocking

Background: It has been estimated that annual incidence of open fractures of long bones is 11.5 per 100 000 personswith 40% occurring in the lower limb and commonest site is the tibial diaphysis. This study was performed to evaluate clinical outcome of patients with open fracture of shaft of tibia.Methods: It was a hospital based observational prospective study was performed on a total of 30 study participants were enrolled and out of them 2 were lost to follow up. After discharge follow up was done every four weeks for clinical, radiological progress of bony union and soft tissue healing.Results: Majority of the study participants were in the age group of 31-40 years (37%). Males were the main study participant (63.3%). The process of healing took for about 13-16 weeks in 57.1% of the study participants were as in 18% of them it healed within 12 weeks. In 25% of the study participants the healing was completed in more than 16 weeks. Conclusions: It has been observed from the study that interlocked intramedullary nailing is a very effective and safe and technique for the management of open tibial fractures