A flexible gate array architecture for high-speed and high-densityapplications

A scaleable gate array has been designed in half-micron CMOS for a wide range of high-speed and high-density applications. Transistor size and position within the basecell provide an efficient implementation of flip-flops, combinational gates, and memory. Design benchmarks have demonstrated 2700 gates/mm² routed density in a 0.5 μm TLM CMOS gate array. Compared to previous 5 V 0.7 μm gate arrays, the new basecell provides improvements of 2.5x in density and 30% in speed, at 70% lower power, NAND-2 delays are 170 ps (FO=2, 3.3 V). Metal-programmable two-port SRAM's feature 3.9 ns typical access times. The new architecture has been implemented in a CMOS gate array family which offers up to 1.15 million available gates and 700 I/O positions     

Soy allergy is not common in atopic children: a multicenter study

This paper describes a release program developed in 1995 for year I hospital based GP registrars in the Rural Training Stream of the Royal Australian College of General Practitioners Training Program in South Australia. Background, objectives, content and organisation, and evaluation are described. The 1996 program that developed from this pilot is also described.     

Retinoblastoma-related protein pRb2/p130 and suppression of tumor growth in vivo

BACKGROUND: The RB/p105 and p107 genes of the retinoblastoma family are tumor suppressor genes whose proteins are inactivated by interaction with T-antigen proteins encoded by polyomaviruses (e.g., simian virus 40 and human JC virus), which have been found to be highly tumorigenic in animals. A variety of indirect evidence suggests that another member of the retinoblastoma gene family, RB2/p130, is also a tumor suppressor gene. To investigate the putative tumor suppressor activity of RB2/p130 more directly, we utilized a tetracycline-regulated gene expression system to control expression of the encoded protein pRb2/p130 in JC virus-induced hamster brain tumor cells and to study the effects of pRb2/p130 on the growth of such tumor cells in nude mice. The ability of pRb2/p130 to interact with JC virus T antigen was also studied. METHODS: Northern blot hybridization analyses were performed on samples of total cellular RNA to measure RB2/p130 and beta-actin messenger RNA levels. Immunoprecipitation and western blot analyses were used to determine T-antigen and pRb2/p130 protein levels and to assess the phosphorylation status of these proteins. Tumor cells were injected subcutaneously into nude mice, and tumor growth, with or without induced expression of pRb2/p130, was monitored. RESULTS: Induction of pRb2/p130 expression brought about a 3.2-fold, or 69% (95% confidence interval = 64%-73%), reduction in final tumor mass in nude mice. We also demonstrated that JC virus T antigen binds hypophosphorylated pRb2/p130 and that stimulation of pRb2/p130 expression overcomes cellular transformation mediated by this antigen. CONCLUSION: Our findings support the hypothesis that RB2/p130 is a tumor suppressor gene.     

Review: JC virus infection of lymphocytes--revisited

JC virus (JCV), the causative agent of the fatal human demyelinating disease progressive multifocal leukoencephalopathy (PML), is an opportunistic papovavirus that infects and destroys oligodendrocytes, the myelin-producing cells of the central nervous system. Since its isolation from the brain of a PML patient, JCV has long been classed as a neurotropic virus. Many studies, however, have demonstrated that JCV can infect various other cell types, including immune system cells. Moreover, several recent studies have focused specifically on lymphocytes as a target of JCV. This review chronicles the association of JCV with lymphocytes, including cell type localization, molecular regulation, and viral sequences, and discusses clinical implications of these findings.     

A system for video-based navigation for endoscopic endonasal skull base surgery

Surgeries of the skull base require accuracy to safely navigate the critical anatomy. This is particularly the case for endoscopic endonasal skull base surgery (ESBS) where the surgeons work within millimeters of neurovascular structures at the skull base. Today's navigation systems provide approximately 2 mm accuracy. Accuracy is limited by the indirect relationship of the navigation system, the image and the patient. We propose a method to directly track the position of the endoscope using video data acquired from the endoscope camera. Our method first tracks image feature points in the video and reconstructs the image feature points to produce 3D points, and then registers the reconstructed point cloud to a surface segmented from preoperative computed tomography (CT) data. After the initial registration, the system tracks image features and maintains the 2D-3D correspondence of image features and 3D locations. These data are then used to update the current camera pose. We present a method for validation of our system, which achieves submillimeter (0.70 mm mean) target registration error (TRE) results.     

High-performance BiCMOS 100 K-gate array

A BiCMOS gate array in 0.8-μm technology with CMOS intrinsic gate delays of 100 ps plus 60 ps/fan-out and BiCMOS intrinsic delays of 200 ps with a 17-ps/fan-out drive factor is discussed. A compact base cell (750 μm²/gate) has been designed with full bipolar drive capability for the efficient layout of both primitive gates and large-arrayed macros, such as register files and multipliers. A 106 K-gate array has been built on a 1.14-cm² chip with ECL I/O capability. The place and route in three levels of metal provide array utilization greater than 90%. The gate array was used to implement a 74 K-gate filter design with testability features such as JTAG and two-phase scan     

Biomimetic poly(glycerol sebacate) (PGS) membranes for cardiac patch application

In this study biomimetic poly(glycerol sebacate) PGS matrix was developed for cardiac patch application. The rationale was that such matrices would provide conducive environment for the seeded cells at the interphase with PGS. From the microstructural standpoint, PGS was fabricated into dense films and porous PGS scaffolds. From the biological aspect, biomimetic PGS membranes were developed via covalently binding peptides Tyr-Ile-Gly-Ser-Arg (YIGSR) and Gly-Arg-Gly-Asp-Ser-Pro (GRGDSP), corresponding to the epitope sequences of laminin and fibronectin, respectively onto the surface. To improve and enhance homogenous binding of peptides onto the PGS surface, chemical modification of its surface was carried out. A sequential regime of alkaline hydrolysis with 0.01 M NaOH for 5 min and acidification with 0.01 M HCl for 25 s was optimal. More COOH chemical group was exposed without causing deleterious effect on the bulk properties of the polymer as revealed by the physicochemical analysis carried out. HPLC analysis, chemical imaging and ToF-SIMS were able to establish the successful homogenous functionalization of PGS membranes with the peptides. Finally, the developed biomimetic membranes supported the adhesion and growth of rat and human cardiac progenitor cells.