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We report the case of a 23-year-old woman with velocardiofacial syndrome (VCFS) and a history of psychosis and seizures. She had been treated with conventional antipsychotic and antiepileptic drugs for 10 and 3 years, respectively. However, she continued to experience occasional hallucinations and paroxysmal jerking of the extremities. L-alpha-methyldopa 500 mg b.i.d. (later reduced to 250 mg t.i.d.) was added to her regimen. Hallucinations and seizures stopped shortly. Over the course of approximately 1 year, the previous medications were discontinued without recurrence of psychotic and epileptic symptoms. Eventually, improved mental functions and behaviour enabled her transition from living in a licensed residential facility to sharing a private residence with a partner. VCFS is associated with haploinsufficiency of catecholamine-methyltransferase, leading to excessive extraneuronal catecholamine concentrations. Alpha-Methyldopa inhibits catecholamine neurotransmission in a variety of ways. It is possible that the drug compensated for genetically disturbed catecholamine transmission thus achieving beneficial effects in this case.

A modified steady-state laser theory that describes a continuous wave (cw) off-resonant Raman laser with asymmetric reflectivities for the cavity is presented. This theory takes into account different mirror reflectivities of the front and back mirrors of the Raman laser cavity for both the pump and the Stokes wavelengths. An off-resonant cw Raman laser pumped at 795 nm in diatomic hydrogen (H2) is modeled by use of the results of the steady-state theory. The predicted threshold for the cw Raman laser is 2.4 mW, and a maximum Stokes photon conversion efficiency of 83.0% is predicted for a pump power of 9.9 mW. The high Stokes photon conversion efficiency is obtained with mismatched pump-wavelength reflectivities of the front and the back mirrors of the laser cavity. By a judicious choice of mirror reflectivities, both the backreflected pump power and the transmitted pump power can be minimized, thus making a maximum amount of pump power available for nonlinear Stokes conversion.

The dynamics of erasure of holographic gratings formed by one-photon and two-photon photorefractive processes in iron-doped (150 ppm) LiNbO3 have been studied as a function of wavelength of the erasing light. For a given wavelength and intensity of this light, the time constant for erasure of holograms recorded at 0.61 μm by a two-photon process is similar to that for erasure of one-photon holograms of the same grating spacing recorded at 0.488 μm. Thus the same ultimate traps appear to be involved in both recording processes. The minimum photon energy required to empty these traps is not greater than 1.9 eV. Rapid erasure occurs when the photon energy is above 2.35 eV.

Holographic gratings with diffraction efficiencies ranging up to 25% can be formed by intersecting cw infrared beams of 1·06 μm wavelength light in single-mode titanium-indiffused LiNbO3 optical waveguides, provided that the guide has been sensitized by passing a broad beam of relatively high intensity red light through it prior to introducing the infrared beams. Such gratings are stable in the dark for at least 24 hours, but can be erased by exposure to a guided beam of visible light. Holograms of diffraction efficiencies of up to 25% can also be formed without the visible-light sensitization step if high-intensity pulses of 1·06 μm light are used. The sensitivity of these holographic recording phenomena appears to vary from wave-guide and from point to point within a given waveguide.

Oral mercumatilin (Cumertilin) satisfactorily controlled congestive heart failure in twenty-two of twenty-five patients without evidence of intolerance or toxicity. Three patients exhibiting unstable or rapidly progressive congestive failure were not benefited.

A pattern recognition system that uses incoherent spatial filtering to recognize images directly from a narrowband phosphor television monitor is described. Images of real objects are captured with a television camera. These images are then edge-enhanced electronically and displayed on the TV monitor. The monitor output is used directly as the input to a holographic correlator. An optical multichannel analyzer at the correlation plane is used to analyze the shape of the correlation function and to determine the position of its peak. Experimental results agree well with theory. Concepts for handling rotation, aspect angle, and scale variations of the input are discussed.

The dynamics of optical erasure of holographic gratings formed by one-photon and two-photon photorefractive processes in iron-doped (150 ppm) LiNbO3 have been studied as a function of wavelength of the erasing light. At a given erasing wavelength and intensity, the time constant for erasure of holograms recorded at 0.61 μm by a two-photon process is similar to that for erasure of one-photon holograms of the same grating spacing recorded at 0.488 μm; thus the same ultimate traps appear to be involved in both recording processes. The minimum photon energy required to empty these traps is not greater than 1.9 eV. Rapid erasure occurs when the photon energy is above 2.35 eV. These results will be compared with erasure dynamics in nominally undoped LiNbO3, and with the recording dynamics in the doped and undoped materials; and the implications for photorefractive recording mechanisms will be discussed.