This study concerns effects on water-borne lead from combinations of chlorine (CL) or chloramines (CA) with fluosilicic acid (FSA) or sodium fluoride (NaF). CL is known to corrode brass, releasing lead from plumbing devices. It is known that CA and CL in different ratios with ammonia (NH) mobilize copper from brass, which we have found also enhances elution of lead from leaded brass alloys. Pha...

Some years ago I visited M. F. Perutz, the Cambridge biochemist who deciphered the structure of the hemoglobin molecule. Professor Perutz showed me a series of artifacts from his 20-year struggle to unravel the twists and folds of the oxygen-carrying protein. There was an x-ray diffraction film whose symmetrical array of dots looked like a lace doily, a contour map of electron density drawn on ...

When a brass compensator is set in a treatment beam, beam hardening may take place. This variation of the energy spectrum may affect the accuracy of dose calculation by a treatment planning system and the results of dose measurement of brass compensator intensity modulated radiation therapy (IMRT). In addition, when X-rays pass the compensator, scattered photons are generated within the compens...

Brass metal work is one of the oldest cottage industries in West Bengal, India. Workers performing rigorous hand intensive jobs are likely to suffer from MSD affecting the upper limbs. The present investigation was intended to establish the prevalence of upper limb MSD among the brass metal workers and to identify the causative factors behind its development. In this study, 50 male brass metal ...

This study investigated whether trachea pressures during brass instrument play of laryngectomised patients are within the range of those measured during tracheoesophageal voicing, and whether application of an automatic speaking valve can 'free' both hands to play a brass instrument. Objective assessment of voicing and music playing parameters was carried out in 2 laryngectomised patients with ...

Presented is an experimental investigation of the machining characteristics and the effect of wire electrical discharge machine (WEDM) process parameters during machining of Al/ZrO2(p) particulate reinforced metal matrix composite (PRMMC). Experiments are carried out to investigate the effects of input parameters such as dielectric conductivity, pulse width, time between pulses, maximum feed ra...

The objective of this review is to report on the progress of the Brigham and Women's Hospital Rheumatoid Arthritis Sequential Study (BRASS) Registry data collection and summarize previous research in understanding therapeutic response to DMARDs using clinical and genetic data. The BRASS Registry, established in 2003, is a large, single-centre, prospective and observational cohort of 1100 RA pat...

This study compared fabr/cation of silver solder joints by dental students using an orthodontic blowpipe .or a Hydroflame ® soldering unit. Fifty-eight students attended a lecture and observed demonstrations of silver solder/ng. Thirty students used a Hydroflame ® to prepare one practice solder joint and two technique solder joints. These students then prepared one practice solder joint and two...

wear is a complicated phenomenon caused by the relative movement of two contacting surfaces compressed together by a normal force. prediction of the wear, in most cases, requires various experiments and microstructural characterization of the contacting surfaces. mathematical models based on physical concepts could provide considerable help in understanding the physical behavior and hence the p...