Dispersion-free fiber transmission for femtosecond pulses by use of a dispersion-compensating fiber and a programmable pulse shaper.

We demonstrate nearly distortionless 2.5-km fiber transmission of sub-500-fs pulses, using a combination of standard single-mode fiber, dispersion-compensating fiber, and a programmable pulse shaper for simultaneous quadratic and cubic dispersion compensation. The dispersion-compensating fiber corrects the bulk of the quadratic and the cubic phases for the single-mode fiber, and the fiber-pigtailed programmable pulse shaper exactly compensates the residual dispersion terms.

Interferometric determination of the quadratic electro-optic coefficient of nitrobenzene.

An interferometric method that was used to measure the electro-optic s(11) coefficient of nitrobenzene is presented. The method uses a Mach-Zehnder interferometer arrangement that produces a finite fringe interferogram. A nitrobenzene Kerr cell is placed in one arm of the interferometer and a pulsed high voltage is applied to the two rectangular electrodes.

Cerebellar ataxia in enteric fever.

In a study of enteric fever, cerebellar ataxia was found to be the commonest neurological manifestation, second only to toxic delirium. Excluding toxic delirium (found in 25-30% of cases) neurologic deficit was noted in 5.0% of a series of 718 consecutive cases; 2.

An unusual family of benign "X" linked muscular dystrophy with cardiac involvement.

A family of benign X-linked muscular dystrophy is described. Two of the 3 affected members appear quite representative of Becker's dystrophy. A third shows no pseudohypertrophy, only gross atrophy, affecting proximal and distal muscles and also shows early onset contractures and electrocardiographic abnormalities and is in these ways much more representative of the variety described by Emery and Dreifuss (1966).

Comparative trial of Co-trimoxazole and Chloramphenicol in Typhoid Fever.

A comparative trial of co-trimoxazole and chloramphenicol was conducted in two groups of 50 patients each to try to resolve conflicting opinions on the relative merits of the two drugs in the treatment of typhoid fever. We conclude that in our part of India co-trimoxazole is superior to chloramphenicol and that differences in our findings to those of others may perhaps be accounted for by differences in strains of Salmonella typhi, ethnic differences, and possibly differences in herd immunity to typhoid.