the paper is based on a study conducted in three different industries on 84.4 on their employees to determine the effect of over all noise intensity, length of employment and rest periods among them. it was found that the mentioned factors have direct effect on the induced hearing loss among the exposed workers. high noise level and long period of employment adversely affect the hearing ability...

Pipe systems are often used to transfer moderate to medium water volumes between reservoirs or from well fields to consumers. Such systems consisting of an arbitrary number of reservoirs or other types of sources and sinks are considered here. The Lagrangean optimization principle is used for the determination of all pipe diameters giving minimum total cost of the system, when the individual di...

background: administration of albumin for burn patients and its effects on mortality and morbidity has been debated for along time. the aim of this study was to evaluate the effects of albumin administration on wound healing, length of hospital stay, weight change, and mortality of burn patients.   methods: two matched groups of patients from shiraz burn care center were randomly selected. the ...

In this work, we use Drude-Lorents model description to study the radiation of a charged particles moving in a homogeneous dispersive medium. A suitable quantized electromagnetic field for such medium is utilized to obtain proper equations for energy loss of the particle per unit length. The energy loss is separately calculated for transverse and longitudinal components of the filed operators. ...

BACKGROUND Alteration in menstrual cycle function is suggested among rhesus monkeys and humans exposed to polybrominated biphenyls (PBBs) and structurally similar polychlorinated biphenyls (PCBs). The feedback system for menstrual cycle function potentially allows multiple pathways for disruption directly through the hypothalamic-pituitary-ovarian axis and indirectly through alternative neuroen...

conclusions hs in total thyroidectomy, reduces operating time, blood loss, postoperative pain, drainage volume, voice changes, and postoperative hypocalcemia, compared to conventional techniques. background traditional haemostatic techniques in total thyroidectomy may cause some damages to surrounding tissues. it is believed that these damages can be reduced using ultrasonic dissector devices l...

The light propagation in optical waveguide must be able to maintain low loss, coupling loss and scattering condition, especially the junction. In this research, a spot size converter is proposed preserve lowest loss. This composed of single mode fiber (SiO2) including inversed taper. input signal from launched into photonic integrated circuits then coupled Si-Slab waveguide. Furthermore, linear...

the rate of soil erosion and sediment yield estimation in the catchment areas is considered as an important factor for soil and water conservation practices. due to difficulties and restrictions in common soil erosion methods, applying a high accuracy method with lowest cost and time consuming would be necessary. assessment of soil loss in hilly areas with capacity of rang land that has changed...