No abstract

The in vitro alterations and in vivo fate of erythrocytes treated with N-ethylmaleimide or subjected to prolonged incubation were studied in normal and splenectomized rats. Minimal injury (20 µM NEM/ml. RBC) resulted in red cells with decreased osmotic fragility and increased plasticity; however, mechanical fragility was significantly increased. These cells were removed with a half-time of 78 minutes, mainly by splenic sequestration, and splenectomy prolonged their life span. Incubation at 37 C. for 21 hours produced erythrocytes with increased osmotic and mechanical fragility and decreased plasticity. Erythrocyte clearance was more rapid (T½ = 59 minutes), with spleen and liver removing approximately an equal number of cells and splenectomy having little effect on red cell life span. With severe injury (40 µM NEM/ml. RBC), all three in vitro measurements showed marked alterations, red cell removal was rapid (T½ = 35 minutes), mainly by hepatic sequestration, and clearance was unaffected by splenectomy. The present studies have shown that chemical injury or prolonged incubation lead to profound changes in in vitro tests of red cell integrity, the mechanical fragility predicting most closely the subsequent in vivo events. Although the entire reticuloendothelial system appears to participate in red cell removal, the spleen and liver are the major sites of sequestration in the rat. The splenic removal predominates with minimally injured cells, hepatic removal with moderately and severely altered cells. The type of injury appears to be of less significance than the degree of injury of the red cells.

The purpose of this study was to assess the ability of the rat to reduce metabolic rate when exposed to deep-penetrating radio-frequency (RF) radiation. Male Sprague-Dawley rats were maintained at an ambient temperature (Ta) of 10 degrees C and exposed to 600-MHz radiation while metabolic rate (MR) was measured by indirect calorimetry. RF radiation exposures were made in a waveguide-type system that permitted the continuous control of specific absorption rate (SAR). SAR's of 2-5 W/kg led to significant reductions in MR when averaged from 30 to 60 min after the initiation of RF radiation exposure. The total decrease in MR during RF radiation exposure accounted for approximately 37% of the total RF heat load. Exposure of another group of rats to the same SAR's at a Ta of 10 degrees C resulted in a significant elevation in colonic temperature. Thus, despite the decrease in MR, heat gain still exceeded heat loss during RF radiation exposure, with a resultant elevation in deep body temperature. In conclusion, in a cold environment the rat exposed to RF radiation decreases its MR. However, the response time and efficiency of the response is not adequate to prevent an increase in body temperature.

This study explores the potential of using deep semantic features to improve binary sentiment classification of paragraphlength movie reviews from the IMBD website. Using a Naive Bayes classifier as a baseline, we show that features extracted from Minimal Recursion Semantics representations in conjunction with back-off replacement of sentiment terms is effective in obtaining moderate increases in accuracy over the baseline's n-gram features. Although our results are mixed, our most successful feature combination achieves an accuracy of 89.09%, which represents an increase of 0.76% over the baseline performance and a 6.48% reduction in error.