An image processing IC for backprojection and spatial histogrammingin a pipelined array

The first VLSI digital signal processor that performs both high-precision image backprojection and spatial histogram calculations at raster-scan rates as high as 30 MHz is described. Realized in 1 μm CMOS technology, this 13.3 mm×13.3 mm chip is designed to handle images as large as 1024×1024 12 b pixels. Loadable coefficients and a unified architecture allow this IC to be used with a variety of computed-tomography scanners for image reconstructions, including fan- and parallel-beam reconstruction. This chip also computes the forward Radon transform, which is a spatial histogram, permitting it to be used for iterative reconstruction algorithms. The bit lengths in the fixed-point architecture assure 12 b reconstruction accuracy     

Simple method for determination of dietary fiber in frozen foods

A simple method was developed for the determination of dietary fiber in multicomponent foods. The method involves dispersing the sample into pH 7.4 phosphate buffer and adding bile and pancreatic enzyme as described. Results were comparable to AOAC methods with correlation coefficients of 86% for multicomponent dinners and 89% for breakfast foods. Coefficients of variation ranged from 7.4 to 20.0% for multicomponent foods and 1.0 to 3.6% for single component foods. In addition, blind duplicate samples had a correlation of 0.99. The described method required less time, labor, and manipulation than AOAC methods.     

Comparative influence of a single allergen exposure on the different components of airway response to methacholine

We compared the effects of an allergen challenge on airway responsiveness to methacholine, the slope of the dose-response curve (DRC) and post-methacholine fall in forced vital capacity (FVC) or forced expiratory volume in 1 s (FEV1)/FVC, and determined whether any changes in these parameters were related to the presence and magnitude of the late asthmatic response (LAR) in mild stable asthma. Twenty-three allergic asthmatic subjects had an allergen challenge, preceded and followed 24 (n = 12) and/or 48 (n = 22) h later by a methacholine challenge. Sixteen subjects had a dual asthmatic response to the allergen. On the post-allergen methacholine challenge, as compared with the pre-allergen test, differences in mean fall in FVC or FEV1/FVC at 20% fall in FEV1 and the slope of the DRC did not achieve statistical significance, even in the group with LAR, which showed a significant increase in airway responsiveness at 24 h. There was, however, a correlation between allergen-induced changes in PC20 and (1) the change in post-methacholine FVC fall in the LAR group at 48 h, and (2) the change in the slope of the DRC in the early-asthmatic-response group at 24 h. In conclusion, allergen-challenge-induced changes in airway response to methacholine are heterogeneous among asthmatic subjects and although it may increase airway responsiveness (PC20), particularly in late responders, it minimally affects the other aspects of airway response to methacholine, suggesting that a more powerful or sustained allergic stimulus is required to modify the latter.     

Spatio-temporal firing patterns in the frontal cortex of behaving monkeys

Recording the activity of several neurons in parallel in the frontal cortex of behaving monkeys reveals that firing times of neurons can maintain +/- 1 ms accuracy even after delays of over 400 ms. The accurate firing structures were associated with behavior. Neural networks that can sustain such accuracy can learn 'learn' to bind with each other and thus may serve as building blocks for cognitive processes.     

Polymerase chain reaction versus culture for detection of Ureaplasma urealyticum and Mycoplasma hominis in the urogenital tract of adults and the respiratory tract of newborns

The efficiency of the polymerase chain reaction (PCR) was compared with that of culture for detection of Ureaplasma urealyticum and Mycoplasma hominis in 726 clinical specimens comprising 189 gynecological samples, 362 urological samples, and 175 samples from newborn infants. The sensitivity of PCR versus culture was 95% for both organisms, while the sensitivity of culture versus PCR was 91% for Ureaplasma urealyticum and 84% for Mycoplasma hominis. Furthermore, PCR tests were faster than culture tests, allowing the time to diagnosis to be reduced from two to five days to 24 h.     

Gentamicin treatment in peripheral vestibular disorders other than Ménière''s disease

Two cases of congenital trabecular hypoplasia of the right ventricle are reported. In the first, the neonatal diagnosis was missed and the child did well until the 13th month of life when a modified Blalock-Taussig shunt was done because of increasing cyanosis. Outcome was good until the 4th year of life when symptomatic atrioventricular block was detected in an emergency situation. A bidirectional Glenn anastomosis and pacemaker implantation were successfully carried out after clinical establization and the child is doing well up to now. The second case presents the disease with its worst features: severe cyanosis and acidosis in the first day of life. A modified Blalock-Taussig shunt was performed and death occurred soon after the operation.