Using Bulk Built-in Current Sensors to Detect Soft Errors

Connecting a built-in current sensor in the design bulk of a digital system increases sensitivity for detecting transient upsets in combinational and sequential logic. SPICE simulations validate this approach and show only minor penalties in terms of area, performance, and power consumption     

High-efficiency resonant-cavity LEDs emitting at 650 nm

We fabricated resonant-cavity light-emitting diodes (LEDs) emitting at 650 nm. Compressively strained GaInP quantum wells were used as an active layer embedded between AlGaAs-AlAs Bragg mirrors. The Bragg mirrors formed a one-wavelength optical resonator. Two devices with different light-emitting areas were compared: 1) a large area chip (300 μm×300 μm) with a conventional LED contact and 2) a small area chip with an 80-μm light opening with an annular contact. Large devices are more suitable for high output power whereas the smaller devices might be useful for data transmission e.g., via plastic optical fibers. For epoxy-encapsulated large area devices, we achieved a maximum wall-plug efficiency of 10.2% and maximum output power of 12.2 mW at 100 mA. The small area LEDs yielded 2.9 mW at 20 mA and a maximum wall-plug efficiency of 9.5%     

Mapping of the spinal muscular atrophy (SMA) gene to a 750-kb interval flanked by two new microsatellites

The gene for autosomal recessive proximal spinal muscular atrophy (SMA) has recently been mapped between D5S629 and D5S557. We report here a new single-locus microsatellite A31 (D5S823) and two multicopy microsatellites 97T-CA and 95/23-CA. The marker A31 maps to the region of overlap between YACs y116, y55 and y122, distal to D5S629; 97T-CA originates from a cosmid corresponding to the STS 97T, localized distally to A31, while 95/23-CA derives from a cosmid corresponding to the STS 97U, localized proximally to D5S557. We tested all our key recombinant families with these markers. In one type I/II SMA family, a recombinant was found that placed the SMA locus distal to D5S823. Homozygosity mapping in a consanguineous type I SMA family indicates that the SMA gene lies proximal to 95/23-CA. Thus, the two new markers, A31 and 95/23-CA further refine the SMA gene to an approximately 750-kb interval.     

A positive systems model of TCP-like congestion control: asymptotic results

We study communication networks that employ drop-tail queueing and Additive-Increase Multiplicative-Decrease (AIMD) congestion control algorithms. It is shown that the theory of nonnegative matrices may be employed to model such networks. In particular, important network properties, such as: 1) fairness; 2) rate of convergence; and 3) throughput, can be characterized by certain nonnegative matrices. We demonstrate that these results can be used to develop tools for analyzing the behavior of AIMD communication networks. The accuracy of the models is demonstrated by several NS studies.     

Primary extranodal lymphogranulomatosis of the flexura dodenal-jejunalis

A primary extranodal lymphogranuloma of Hodgkin was found in the small bowel (PS II AE) of a 34-year-old man. Two years after radical surgery followed by local telecobalt therapy, the patient is in good health. The symptomatology, therapy and prognosis of this rare form of Hodgkin's lymphogranuloma are briefly reviewed.