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Pyoderma gangrenosum (PG) is a rare skin disorder of unknown etiology that is believed to be part of the spectrum of neutrophilic dermatoses. Although 25% to 50% of cases are idiopathic, PG is associated with systemic disease in up to 70% of patients, most notably inflammatory bowel disease, rheumatoid arthritis, and paraproteinemia. Although a multitude of PG cases after breast reduction have been reported, only recently has an association of PG with breast reconstruction been acknowledged. In the present article, the case of postsurgical PG (PSPG) after autologous breast reconstruction is presented along with a review of the literature. The importance of early diagnosis and initiation of appropriate treatment is discussed. The authors discuss the possibility that the increased number of breast reconstructions being performed may increase the incidence of PSPG cases seen by plastic surgeons. As such, it is critical to remove PSPG from the list of "exotic" diseases and place it higher on the list of differential diagnoses as delays in treatment can result in debilitating complications with substantial patient morbidity.

Smart-looking clothes have been designed for wheelchair users. These clothes make dressing faster and easier, and the clothes fit better than the standard garments. The special features for new adaptive clothing for wheelchair users include easy handling fastenings, quick-access garment openings, conveniently placed pockets, custom-curved trousers, slacks, and jackets, custom-shaped dresses and skirts, ponchos or custom-made coats, easy-fit undergarments, and durable styled fabrics. These clothing adaptations are attractive and give the wearer and the observer the feeling that the person with the disability is not set apart by the clothing he or she wears.

The growth of optical radiation, scattered transverse to the pump axis by stimulated Brillouin scattering (SBS) in optical windows, is considered. Basic equations are presented, and an analytic expression that determines the parasitic buildup time is derived for a transverse SBS geometry. Losses suffered by the scattered optical radiation are included in a bulk-loss term. Calculations are performed for fused-silica windows and compared with a numerical model. This parasitic process may affect the design of laser systems that will generate multinanosecond, multikilojoule, narrow-band pulses in the ultraviolet region.

Two different types of KrF lasers currently being analyzed as potential laser-fusion drivers: large electron-beam (e-beam)- pumped amplifiers using pure optical multiplexing for pulse compression and small e-beam sustained discharge lasers using a hybrid pulse compression technique. Both types of KrF lasers appear able to satisfy all of the requirements for commercial-applications ICF drivers, including cost, efficiency, pulse shaping, energy scaling, repetition rate, reliability, and target coupling. The KrF driver can effectively operate at efficiencies > 10% and can contribute < 10 mill/kWh to the cost of electric power production, with the total estimated cost of electricity from either KrF laser system being comparable (25 to 50 mill/kWh, 1985 dollars) with the cost from other methods of electric power production. The Aurora facility is described.

Ti:sapphire oscillators longitudinally pumped by doubled Nd:YAG laser radiation are a useful source of tunable near-IR radiation. Unfortunately the design and modeling of these oscillators involve considerations which are different from standard flashlamp pumped storage laser systems. We present the resonator design considerations to avoid resonator optics damage at low fluences and the material/optical kinetics required to achieve a detailed fit between experimental and numerical results. Modeling parameters include Ti:sapphire kinetics, gain switch optical kinetics, bandwidth, and a comparison of 1-D, 2-D, and 3-D physical optics modeling of the optical mode.

We observed a reduction in the absorption of 532-nm laser radiation by Ti:sapphire with increased laser fluence up to 3.5 J/cm2. This effect was observed for all Ti:sapphire samples studied, six crystals as of now, and is attributed to saturation of the optical transition of the Ti3+ ions. Since 532-nm radiation is used to pump Ti:sapphire lasers, it is important to know its absorption characteristics to understand completely the laser performance. However, this saturation effect is more important as an accurate method of measuring dopant ion density and absorption cross section independently. The transmittances of Ti:sapphire at 532-nm were measured with respect to incident laser fluence and fitted to a numerical saturation model using a nonsteady-state rate equation analysis based on the Franz-Nodvick approach. Upper-state fluorescence was ignored since absorption occurred on a time scale (≈10 ns) short compared to the fluorescence lifetime (≈3.2 μs). The fitted parameters were the weak-signal transmittance T0 and the saturation flux Esat (hν/σ) from which the absorption cross section and dopant ion density can be determined. For example, using a 2.1-cm Ti:sapphire sample having a weak-signal absorption coefficient of 1.58 cm−1 at 532 ran, the Esat was 7.7 J/cm2 which gave a cross section of 4.8 × 10−20 cm2 and a Ti3+ density of 3.3 × 1019 cm−3, consistent with estimates of the total Ti density.