Case report: pneumomediastinum and pneumothorax complicating colonoscopy

Colonic perforation is potentially the most serious complication of colonoscopy. Both the clinical manifestation and rapidity of onset of symptoms can vary depending on whether the perforation occurs directly into the peritoneal cavity or into the retroperitoneal space. Colonic perforation is often associated with abdominal pain, although more uncommon presentations have been documented. A case report of a unilateral pneumothorax and pneumomediastinum complicating colonoscopy is described, which responded well to conservative measures without recourse to surgical intervention, antibiotic therapy or parenteral alimentation.     

Limb salvage with osteoarticular allografts after resection of proximal tibia bone tumors

A retrospective study was performed between 1980 and 1995 on 38 recipients of proximal tibial allografts after wide resection of benign and malignant tumors. Twenty-one (55%) patients experienced one or more complications. Of the 26 patients who received chemotherapy, 15 (58%) experienced one or more complications, whereas of the 12 patients who did not receive chemotherapy, six (50%) experienced one or more complications. In the chemotherapy group, there were 12 (46%) fractures, four (15%) infections, three (12%) nonunions, and four (15%) instabilities. In the nonchemotherapy group there were three (25%) infections, two (17%) fractures, one (8%) instability, and one (8%) nonunion. These complications were managed adequately with multiple subsequent surgical procedures. Three patients underwent amputations for deep wound infections. Twelve (32%) patients underwent removal of the allograft, and the limb was salvaged by reallografting or by total knee arthroplasty. The results of both groups were 66% (25 of 38 patients) satisfactory (good or excellent). The chemotherapy group had a significantly higher incidence of fractures. All other complication rates and functional outcomes were not significantly different between these groups.     

Signature murders: a report of several related cases

Three female patrons of singles bars were murdered in separate events in Bellevue, Washington in 1990 within sixty-seven days of each other. An evaluation of those murders revealed that all the murders were linked by a distinct personal "signature" or "calling card" left by the killer. As reported in the literature, the modus operandi of a killer frequently changes from one murder to the next and is different from the killer's signature, which is a permanent psychological imprint at each scene. The murder cases reported here demonstrate an elaborate signature of one killer who engaged in a rare personalization of his necrophilic fantasies by posing, openly displaying, and sexually inserting foreign objects into each one of three victims' bodies.     

The effect of addition of high-density polyethylene on the crystallization and mechanical properties of polypropylene and glass-fiber-reinforced polypropylene

High-density polyethylene up to about 30% by weight was melt-mixed with polypropylene and short-glass-fiber-reinforced polypropylene. The presence of high-density polyethylene and glass fibers in the polypropylene matrix affects its crystallization characteristics, which were studied with the help of differential scanning calorimetry. The blend and composite samples have a large number of polypropylene domains apparently due to an abundance of surface nuclei; as a result, the tensile strength, tensile modulus, and toughness are enhanced. The temperature dependence of shear modulus and logarithmic decrement indicate that high-density polyethylene can have plasticizing effect below the glass transition temperature of polypropylene. The scanning electron micrographs of fractured ends show the presence of dispersed domains in the composite samples.     

The effect of reduction potential on charge/discharge reactions on porous lead-bismuth electrodes (positives)

A series of discharge experiments were performed from the PbO₂/O₂ region to various reduction potentials using the potential step technique. Two distinct potential ranges were observed, one which occurs at potentials between 1050 and 1100 mV and the second, where there was a much larger output of capacity between 400 and 700 mV. Between these two regions there is a plateau where the relatively small output in capacity during discharge experiments enables almost complete recharging to be effected. The data presented here shows that once the electrode has entered the second reduction region it is virtually impossible to recharge the electrode using this experimental technique.     

Startup of a pipeline containing settled solid particles

Experimental studies have shown that, provided a threshold velocity is exceeded, bed of solid particles can be displaced from pipelines at low pressure gradients using fluid velocities near the limit-deposit velocity. The time scale of the process depends upon three factors: fluid acceleration, bed erosion and displacement. Results are reported for water slurries of a silica send of d₅₀ = 0.43 mm. A simple model for the transient response is proposed.