Aleef Rahman

Osteoporosis in Female Athletes

Osteoporosis is a condition that affects almost 10 per-cent of the total female population worldwide and is especially prevalent among female athletes. This dis-ease is characterized by a decrease in bone mass and density and enlargement of bone spaces producing po-rosity and fragility. With the number of women of all ages participating in physical activity steadily increas-ing, the relationship between osteoporosis and female athletes is a growing concern [1-4]. It is estimated that more than 6 million women now compete in strenuous exercise, worldwide. Despite the benefits of exercise, excessive and strenuous physical activity can have neg-ative effects on the reproductive and skeletal systems, leading to osteoporosis [5,6]

A modularized battery charge equalizer in the application of electric vehicle

For traction of electric vehicles, the motor utilizes battery strings (cells) connected in series. These battery strings suffer from the problem of charge unbalancing due to charging and discharging, chemical degradation and ambient temperature. Contemporary research has reported many charge balancing circuit systems for equalizing the charge among the battery strings of cells. However, charge balancing remains a challenging task as the large number of cells used these days in conventional charge equalizer systems. In this paper, a modularized charge equalizer based on series resonant converter has been designed where the switching loss, conduction loss, balancing time are explored. In the proposed modularized system, the circuit size and cost is minimized and efficiency is increased. In addition, zero current switching have been achieved during turn off intervals of switches.

A Battery Charge Balancing system with reducing inrush high spike current for electric vehicle

A charge equalizer system is suggested for use in the future battery-packs employed in plug-in vehicles or house used in UPS-based supply systems deriving energy for supplementing the grid-connected main supply. Such applications are becoming common in Distributed Generation on spot from sources of solar (or wind), especially when grid connected power-supply is interrupted for some reason. The charge equalizer circuit is using resonant circuit, being operated by the switching frequency showing results the effect of when compared to the resonant frequency. The inrush current raises in the switching components of the resonant circuit due to inductor components. This inrush current may damage the switching component and increase the total system cost. In this work, flyback snubber circuit consisting of diode and capacitor has been used for reducing inrush high spike current. In addition, Zero current switching is achieved in this system for reducing the circuit losses.

Effect of lidocaine on bone matrix formation by osteoblasts

Local anesthetics are widely used as an intraosseous injection particularly in the field of dentistry. Occasionally, large doses of anesthetics are injected to elicit the desired effect during many surgical procedures. In this study we examined the effect of a local anesthetic, lidocaine, on osteoblasts as there are only a few reports on the effect of local anesthetics directly on bone cells. Our results showed that physiological as well as supra physiological concentrations of lidocaine cause cell death. At low concentrations, lidocaine was found to enhance both proliferation of osteoblasts and bone matrix production. In addition, low concentration of lidocaine increased the expression of osteocalcin, a key regulator in the signaling pathway of bone matrix production. Our results show that lidocaine has a biphasic effect on osteoblasts and low concentrations of this anesthetic may assist in bone matrix production. This preliminary study can lead to the therapeutic usage of intraosseous lidocaine as a bone strengthening agent.

An Unusual Case of Neurogenic Sexual Dysfunction Due to Lead Exposure

An unusual case of sexual dysfunction due to autonomic neuropathy, secondary to lead poisoning is reported in a radiator repair car mechanic. Pathophysiology of sexual dysfunction secondary to lead induced autonomic neuropathy is discussed. Neurologists who treat sexual dysfunction should be made aware of relationship of metal toxicity producing neurogenic sexual dysfunction.