A GaAs-GaAlAs injection laser has been tested that confines light in the lateral dimension (normal to junction plane) by a multilayer Bragg reflector. In the past, light has been confined as a result of the higher-index guiding region and resulting evanescent fields.

The optimal treatment for endometrial carcinoma is radical hysterectomy and hemivaginectomy with pre-operative caesium sources in the uterus and vaginal vault. Block pelvic lymphadenectomy is unsatisfactory, and gland extension is best treated by radiotherapy to the lateral pelvic and para-aortic fields. Surgery has a definite place in the treatment of advanced cases.

A recent study of cat visual cortex reported abrupt changes in the positions of the receptive fields of adjacent neurons whose preferred orientations strongly differed (Das & Gilbert, 1997). Using a simple cortical model, we show that this covariation of discontinuities in maps of orientation preference and local distortions in maps of visual space reflects collective effects of the lateral cor...

Lateral inhibition between near-neighbor neurons has long been thought to be important for narrowing the receptive fields of neurons in many sensory systems. A new study by Poo and Isaacson in this issue of Neuron examining olfactory processing finds that "global" inhibition within the primary olfactory cortex might accomplish a similar end.

Recent theoretical results on magnetotransport of electrons in a 2D system in the range of moderately strong transverse magnetic fields are reviewed. The phenomena discussed include: quasiclassical memory effects in systems with various types of disorder, transport in lateral superlattices, interaction-induced quantum magnetoresistance, quantum magnetooscillations in dc and ac transport, and os...

Digital interference holography (DIH) is being developed as a novel method of microscopic 3-D imaging. A number of holographic fields are numerically calculated from optically recorded holograms using a range of wavelengths. Numerical superposition of these fields results in a tomographic representation of the object with narrow axial resolution. We demonstrate the practicality of DIH in micros...

Rotor dynamics plays an important role in many engineering fields such as gas turbine, steam turbine, reciprocating and centrifugal compressors, the spindle of machine tools, and so on. Owing to the growing demands for high power, high speed, and light weight of the rotor-bearing system, computations of critical speeds and steady-state response at synchronous and sub critical resonances become ...

The electrosense of sharks and rays is used to detect weak dipole-like bioelectric fields of prey, mates and predators, and several models propose a use for the detection of streaming ocean currents and swimming-induced fields for geomagnetic orientation. We assessed pore distributions, canal vectors, complementarity and possible evolutionary divergent functions for ampullary clusters in two sh...