the aims of surgical treatment for cholesteatoma include complete removal of disease and formation of a dry, self cleaning ear in addition to hearing reconstruction. this presentation concentrates on techniques of open mastoid surgery or modified radical mastoidectomy to achieve a well-constructed cavity. this study analyzes both primary and revision mastoid surgery referred to the author. all ...

This work is the first extensive study on the removal of carbon monoxide from polluted air in biofilters. It compares the performance of two packing materials, namely lava rock alone and a mixture of peat and lava rock. The results show that the biofilter packed with the mixture of peat and lava rock performed much better than the other one. The effect of operating conditions as, among others, ...

a mixed solar dryer with a specific mechanism to vary the tilted angle of collector, is utilized to fulfill all tests. the efficiency of the dryers is low because of various reasons such as heat loss of air in an open flow circuit. getting air back toward the air inlet of dryer can increase the efficiency of dryer and decrease drying process period. a new mechanism considered for dryer which co...

There is currently scarce information on the occurrence and distributions of Polycyclic Aromatic Hydrocarbons (PAHs) in the air from industrial estates in Nigeria. Hence, the present study aims to evaluate the extent and sources of pollution of polycyclic aromatic hydrocarbons in the air from some industrial estates in Lagos and Ogun States, Nigeria. Ten air samples have been collected from the...

Nuclear Waste Management Organization of Japan (NUMO) has proceeded with repository siting, since 2002, based on an “open solicitation procedure”. While waiting for volunteer municipalities and having no specific site geological information, NUMO has been preparing for expected assessments and designs at the investigation stage. One of the efforts for preparation is the dry run using hypothetic...

the main rock mass classification systems make use of similar rock mass parameters. due to lack of comprehensive estimation systems, determining the real specifications of jointed rocks faces some difficulties. a vast number of parameters with various degrees of impact are involved in such definitions. combination impact of all the effective parameters is to be figured out in order to come up w...

Rock, air and service water samples were collected for microbial analyses from 3.2 kilometres depth in a working Au mine in the Witwatersrand basin, South Africa. The approximately metre-wide mined zone was comprised of a carbonaceous, quartz, sulphide, uraninite and Au bearing layer, called the Carbon Leader, sandwiched by quartzite and conglomerate. The microbial community in the service wate...

sustainable and energy efficient design issues are key to the way good buildings are designed in the 21st century. no building designer today should be without the basic skills offered by the unique multidisciplinary studies of architectural design, based on energy use in buildings. however, this paper is focusing of effect of air movement on human comfort, as a key element of building design. ...