Why should a deformed, anaesthetic, functionless hand be wanted?

A 58-year-old woman presented at a disability assessment tribunal with a severely deformed left forearm. She had broken the arm 25 years previously and the infected open fracture had not healed. There were no sensory or motor functions in the hand, which the patient kept constantly hidden in her garments. The question of an amputation was raised and the advantages of modern prosthetics with respect to cosmesis and function failed to convince the patient that she might benefit from such surgery. One questions why a patient should want to retain this cumbersome, obviously embarrassing, burden and whether the question of surgery should have been raised.     

Design and analysis of double-fused 1.55-μm vertical-cavitylasers

Detailed design and experimental characterization of three generations of double-fused vertical-cavity lasers are described. The result of this design evolution is the first above-room-temperature continuous-wave operation of long-wavelength vertical-cavity lasers. Threshold currents of 2.3 mA and yields greater than 90% have been obtained     

Multimode effects on the evolution and long-term stability of apassively mode-locked laser under pulsed injection locking

A multidimensional extension of the injection locking of CW lasers has been recently presented and experimentally verified when both a passively and an actively mode-locked laser were locked to injected coherent pulse trains. Harmonic injection locking of a passively mode-locked laser, where a subset of the laser cavity modes were locked to the injected signal, was also recently realized in a fiber laser to yield trains of 6-ps pulses at rates of up to 40 GHz. In this paper, the multimode injection-locking process is addressed with an emphasis on the long-term dynamics of the laser, pulse buildup under injection locking, memory effects, noise mechanism as well as potential applications, e.g., optical signal regeneration. Using a recently introduced formalism for describing passively mode-locked lasers, the experimental results are compared to numerical simulations     

Noise in pulsed injection locking of a passively modelocked laser

In this paper, noise effects related to pulsed injection locking of a passively modelocked laser (PML) are analyzed. A set of nonlinear equations, derived from a soliton perturbation method, is used to describe the modelocked laser pulse evolution, under injection locking. The equations are linearized, and the stability of the injection locked solution is studied. Subsequently, the linear equations are employed to describe the coupling of both the injected signal noise and the internal noise, to the locked pulses. Noise reduction due to the injection process is demonstrated, with important implications for all optical signal regeneration and synchronization     

On spontaneous emission into guided modes with curved wavefronts

The problem of spontaneous emission into guided modes with curved wavefronts is examined quantum mechanically. A classical result due to Petermann, which shows an increased emission rate relative to modes with planar phase fronts, is corroborated.     

Lexicons

The three lexicons used by KBMT-89 are described: A concept lexicon constitutes the sublanguage domain model for specifying semantic information; it is maintained by Ontos, a knowledge-acquisition and maintenance system. An analysis lexicon is a dictionary containing syntactic information and mapping rules required for semantic parsing. And a generation lexicon, similar to the analysis lexicon, is employed in the generation phase.     

Recommended guidelines for optimal design of a plastic surgery service during mass casualty events

OBJECTIVE: The objectives of the study were to evaluate the pattern of plastic surgery (PS) team intervention during the first 12 hours after a mass casualty blast. METHODS: The records of 272 civilians injured from 1994 to 1997 in Tel Aviv were reviewed. Patients' injuries were classified according to the nature of their PS injury and the type of PS intervention. The procedure time and number of plastic surgeons involved were recorded in 20-minute intervals. The average and standard deviation of the peak demand (PD) timing for PS intervention were calculated. Linear correlation between the PD and the total number of wounded transferred to the Tel Aviv Sourasky Medical Center was evaluated by the correlation coefficient. RESULTS: A distinct "double-peak" and five phases pattern of PS team intervention were observed. A linear correlation and a 1:5 ratio were found between the total number of wounded transferred to the Tel Aviv Sourasky Medical Center and the PD for PS intervention. CONCLUSIONS: PS involvement has a predicted pattern related to the patient volume. Guidelines based on the conclusions drawn from this study can ensure an ordered, efficacious level of PS care during these events. A triple team plan is suggested, and adjustments in medical resources according to the specific nature of the event are described.     

Changes of mobility along a depletion type MOS transistor channel

The characteristics of a depletion type N-channel MOS transistor, with a built-in inversion layer, show considerable deviation from the behaviour expected of a device with a constant effective mobility along its channel. Experiment indicates reduction of the mobility in the direction of the drain due to the action of the drain induced field. A functional dependence of mobility on this field leading to a constant velocity is assumed and a set of equations describing this method is derived for various ranges of drain voltage. A special device, with voltage probes situated along its channel, was constructed and the drain characteristics, saturation point and potential distribution along the channel for the drain-field dependent mobility model and the constant mobility model were compared with experimental results obtained from it. The variable mobility model was shown to be in much better agreement with experiment.     

n-channel enhancement m.o.s. transistor built in germanium-doped silicon

Shallow diffusion of germanium into silicon, performed in a vacuum or an open-tube furnace and followed by dry oxidation, results in a C/V curve positively shifted by about 1 V for a 1000 ? thick oxide layer. The shift is due to negative charges in the oxide, which make possible the manufacture of n-channel enhancement metal?oxide?semiconductor transistors with an inversion-layer mobility of 770 cm2/Vs and a threshold voltage of +0.8 V.     

Harmonic mode-locking using regenerative phase modulation

In this letter, we report stable operation of a 1-GHz passively modelocked fiber laser synchronized by regenerative phase modulation. The minimum pulsewidth obtained was 600 fs and the laser amplitude noise was typical of low-noise passively mode-locked fiber lasers