Cortical function in 107 patients with supratentorial expanding mass. Pre- and postoperative study

A clinical study on functions of the cerebral cortex is reported. In this regard, 107 patients with a supratentorial expanding mass have been investigated before and after surgical removal of the lesion. The results obtained are discussed in the light of what is available in the literature.     

Intracranial epidermoid and dermoid cysts. Results of microneurosurgery

A number of radon-related properties have been surveyed in underground shopping centers in Hong Kong. These parameters include the radon concentration, the total potential alpha energy concentration of radon progeny, the equilibrium factor and the unattached fraction of radon progeny. The mean values recorded for these were 29.2 +/- 7.8 Bq/m3, 3.60 +/- 1.53 mWL, 0.46 +/- 0.16 and 0.05 +/- 0.03, respectively. Based on these figures, we have calculated the average radon dose received by employees in an underground shopping center in Hong Kong to be 0.22 mSv/yr, which represents an approximate increase of 8% over the total dose of about 2.7 mSv/yr received by the average person in Hong Kong.     

Solitary capillary hemangioblastoma, cellular variant. Clinical, radiological, and anatomo-pathological study of 2 cases

Two cases of the rare cellular variant of the solitary capillary haemangioblastoma are reported. On MR study both tumors appeared as cerebellar contrast-enhancing masses, without evidence of intra- or perilesional blood vessels. Histologically, they showed compact groups of polygonal or rectangular cells separated by compressed small capillaries. There were no reticulin fibres among cell clusters. The stromal cells were found to be immunopositive for neuron-specific enolase (NSE), factor VIII-related antigen (von Wille-brand factor), Ulex europaeus lectin, and glial frillary acidic protein (GFAP). The findings are discussed in light of the pertinent literature.     

Posttraumatic syringomyelia. A report of an atypical case

Isolated congenital lymphoedema of the external genitalia in boys is extremely rare. It can have major physical and emotional consequences for the children. Three male patients with primary lymphoedema of the penis and scrotum are described. The first case presented with lymphoedema of the prepuce and the phallic skin that persisted after the age of 1 year. Circumcision and excision of the subcutaneous tissues of the phallic skin were successful in producing the appearance of a normal circumcised penis. The second case presented with oedema of both phallic and scrotal skin. At age 1 year only a pastous thickening of the prepuce remained, scrotal and phallic skin normalised spontaneously. Routine circumcision was successful with a 5-year follow up. The third case presented with persistent oedema of both the scrotum and the phallus. He suffered leakage of lymph requiring incontinence pads, with complicating skin infections recurring every 4-6 weeks at age 8 years. After complete peeling of the scrotal and phallic skin from subcutaneous tissue some leakage persisted, infections subsided. The cause of this disorder remains unknown, although hypoplasia of the lymphatic vessels is reported in most cases. In the literature, several congenital malformations have been associated with primary lymphoedema. These were not noted in our patients. Rarely, the lymphoedema regresses spontaneously. The treatment of persistent lymphoedema is surgical and consists of meticulous excision of all subcutaneous layers of the affected skin, combined with reconstruction of the penis and/or scrotum. CONCLUSION: Primary lymphoedema of the male external genitalia is an extremely rare malformation of the lymphatic vessels of unknown origin. If persistent, surgical treatment is necessary.     

SCMP: A Single-Chip Message-Passing Parallel Computer

As technology improves and transistor feature sizes continue to shrink, the effects of on-chip interconnect wire latencies on processor clock speeds will become more important. In addition, as we reach the limits of instruction-level parallelism that can be extracted from application programs, there will be an increased emphasis on thread-level parallelism. To continue to improve performance, computer architects will need to focus on architectures that can efficiently support thread-level parallelism while minimizing the length of on-chip interconnect wires. The SCMP (Single-Chip Message-Passing) parallel computer system is one such architecture. The SCMP system includes up to 64 processors on a single chip, connected in a 2-D mesh with nearest neighbor connections. Memory is included on-chip with the processors and the architecture includes hardware support for communication and the execution of parallel threads. Since there are no global signals or shared resources between the processors, the length of the interconnect wires will be determined by the size of the individual processors, not the size of the entire chip. Avoiding long interconnect wires will allow the use of very high clock frequencies, which, when coupled with the use of multiple processors, will offer tremendous computational power.