ABSTRACT
An isopiestic experimental facility for the measurement of vapor pressures has been designed, fabricated, and commissioned. Using the vapor pressure data as a function of temperature, useful thermodynamic properties of alloys and compounds of interest can be derived. The isopiestic facility comprises a pair of furnaces, temperature controllers, thermocouple movement mechanism, user interface, and data collection. Four such experimental setups have been commissioned. This experimental facility is useful to determine the vapor pressures of a volatile component over the condensed phases as a function of temperature and composition. Using the vapor pressure data, the thermodynamic properties of various systems can be determined. The experimental setup was validated by a Pr-Cd isopiestic run, and the results are compared with the data reported in the literature.
ABSTRACT
Osteochondromas are common benign bone tumours. They usually occur in the patients who are below thirty years of age. They probably are developmental malformations rather than true neoplasms. They are believed to originate within the periosteum as small cartilaginous nodules. The foot is rarely a common site of presentation for these tumours. The calcaneum is one of the most unusual regions for the occurrence of osteochondromas 1. The osteochondromas which arise from the calcaneum, especially those which project onto the plantar surface, pose considerable problem to the ambulation. Malignant transformations are seen in less than 1% to 2% of the patients with solitary osteochondromas 2. We herewith present a case of osteochondroma which arose from the calcaneum, which was surgically excised to improve the patient's daily functioning. The patient was followed up for a period of one year. She is now able to walk comfortably.
ABSTRACT
OBJECTIVE: To describe a previously unreported syndrome of recurrent syncopal attacks provoked by light stimulation of the external auditory canal. CASE REPORT: A 13-year-old girl had been receiving treatment for presumed absence seizures, with inadequate treatment response. Imaging was normal. Careful history taking indicated that the recurrent syncopal attacks were precipitated by external auditory canal stimulation. Targeted autonomic function tests confirmed a hyperactive vagal response, with documented significant bradycardia and lightheadedness, provoked by mild stimulation of the posterior wall of the left external auditory canal. Abstinence from ear scratching led to complete alleviation of symptoms without any pharmacological treatment. CONCLUSIONS: Reflex syncope consequent to stimulation of the auricular branch of the vagus nerve is proposed as the pathophysiological mechanism for this previously undocumented syndrome.
