Provide Safety Measures Research Articles

Flexible Seasonal Timing and Migratory Behavior: Results from Stonechat Breeding Programs

Rigid schedules of long-distance migrants could be among candidate traits for adaptive migratory syndromes. This prediction was tested on stonechats, passerines that differ widely in migratory behavior and seasonal schedules. Stonechats in Europe are short-distance migrants and multiclutched, whereas African residents and Siberian long-distance migrants usually raise single broods. In captivity, all subspecies displayed endogenous cycles of reproductive development and molt. The subspecies differed in time afforded to life cycle stages. Under conducive aviary conditions, African stonechats were multibrooded, whereas Siberian stonechats did not add clutches. This difference in flexibility was exclusively related to the length of breeding windows. Stonechats also differed in premigratory preparations. Postjuvenile molt started early in Siberian stonechats, but in European and African stonechats, depended strongly on hatching date. In contrast, all subspecies shortened molt duration at the same rate when hatched from late broods. Plasticity of Zugunruhe timing was identical in Siberian and European subspecies and nearly compensated for hatching late. The stonechat data suggest a refined understanding of temporal plasticity in long-distance migrants. Overall, plasticity was not reduced, but was differently organized. Apparently rigid migrant schedules were related to short breeding cycles and inflexible molt onset. Short windows for breeding and juvenile development could provide safety measures for timely departure. Once molt was initiated, temporal plasticity of long-distance migrants matched that of less migratory conspecifics. In addition to adjusting endogenous programs, stonechats differed in implementing them in the field. Modifying the conditions under which programs are expressed may be an efficient way to enhance seasonal plasticity.

GRADUAL DAM BREACH FLOW ROUTING

ABSTRACT A large number of impounding reservoirs are constructed to meet the demand for domestic water supply, municipal and industrial water needs, irrigation, power generation etc. It is envisaged that the construction of large impounding reservoirs also involves the preparation of emergency action plan due to the collapse (masonry)/breaching (earth) of the dam, in the form of providing safety measures and relief to the affected. Large volumes of water will be released into the downstream river gorge due to failure of the dam and the extent of relief measures depend on the propagational characteristics of the flood wave. Such problems have been studied by mathematical models involving numerical solutions. These models, however, require extensive data relating to the river gorge cross-section (including roughness parameter) and the reservoir bathymetry. This analysis is further sensitive to the unknown and uncertain characteristics of the breach geometry and the time of breach development. A brief and critical review of the art of dam breach flow routing analysis presented followed by illustration of a simple numerical model for the routing of the dam breach flows to suit to the readily available data of dam and river cross-sections.

Noise problem in a polyester fiber plant in Pakistan.

Noise study has been undertaken in the three units of a polyester fiber plant. The level and frequency characteristics of the prevailing noise have been studied and speech interference levels evaluated. The results are discussed with reference to the maximum permissible occupational noise exposure limits as allowed by the ISO and other national standards. Some recommendations have also been made to provide safety measures to the workers against high level noise in these units.