Parboiling of rice. Part I: Effect of hot soaking time on quality of milled rice

This study investigated the effect of soaking time on the quality of parboiled rice. The paddy was soaked in water at 25 and 80 °C for 15, 30, 45, 60 and 120 min. The soaked paddy was steamed, dried, stored and milled. With increasing soaking time a significant increase in water absorption and milling and head rice yield (hence reduction in broken rice) was observed. A significant difference in milling yield, at the 1% level, was obtained between the raw rice control and the hot soaked parboiled samples. A large reduction in fissured grain was observed after soaking. It is suggested that parboiling fills the void spaces and cements the cracks inside the endosperm, making the grain harder and minimizing internal fissuring and thereby breakage during milling.     

Assessment of asbestos burden in the placenta and tissue digests of stillborn infants in South Texas

Between June 1986 and May 1997, chronic wasting disease (CWD) was the only natural cause of adult mortality among captive Rocky Mountain elk (Cervus elaphus nelsoni) held at a wildlife research facility near Fort Collins, Colorado (USA). Of 23 elk that remained in this herd > 15 mo, four (17%) developed CWD. All affected elk were unrelated females from the founding cohort, captured as neonates and raised in 1986. The index case was diagnosed in 1989; time intervals between subsequent cases ranged from 13 to 32 mo. Initial age at onset of clinical signs ranged from about 2.9 to 8.1 yr; duration of clinical disease ranged from 5 to 12 mo (mean = 7.5 mo) prior to death. Intraspecific lateral transmission of CWD seemed the most plausible explanation for the epidemic pattern observed; neither periparturient nor maternal transmission appeared necessary to sustain this outbreak. Early detection and elimination of incubating or clinical individuals may have aided in reducing exposure or infection rates as compared to a previous outbreak in the same facility. Transmission routes and rates, pathogenesis, antemortem diagnostic tools, and the potential role of reservoirs or environmental contamination in perpetuating CWD epidemics warrant further investigation.     

Photogenerated base as catalyst for imidization reactions

The photogeneration of free amines or diamines from soluble organic precursors such as photoactive 2-nitrobenzyl carbamates is useful for the imidization of polymers containing amic acid or amic ester moieties. The base-catalyzed reaction occurs at lower temperatures than the non-catalyzed thermal process and is applicable to the patterning of polymer coatings or thin films.     

Amplification refractory mutation system linear extension: a novel, gel-free, enzyme-linked immunoassay method for DNA genotyping

A single synthesis cycle of the amplification refractory mutation system (ARMS) was applied to the analysis of K-ras alleles amplified by polymerase chain reaction and immobilized in streptavidin-coated microtiter plates. The ARMS cycle provided the specificity and molecular switch characteristics of a conventional ARMS assay. This allowed linear extension from an allele-specific primer and the incorporation of digoxigenin-labeled deoxyuridine monophosphate from digoxigenin-11-deoxyuridine triphosphate in the presence of the appropriate K-ras allele. Any digoxigenin-labeled deoxyuridine monophosphate substitution was then demonstrated by enzyme-linked immunoassay with colorimetric endpoint. This method is capable of detecting underrepresented acquired mutations, and this has been shown by the unambiguous detection of specific K-ras mutations in cell line DNA/normal human genomic DNA admixtures. The characterization of K-ras mutations in frozen colorectal tumor samples and histologic material is also described.     

The effect of water sorption on the dynamic modulus of elasticity of desiccated concrete materials

The effects of desorption and water sorption on the dynamic modulus of concrete, mortars and hardened Portland cement paste are investigated. Desiccation of the latter results in a significant reduction in the dynamic modulus. Cyclic drying and wetting of the concrete system further decreases the modulus value. Shrinkage induced microcracking is proposed as the major mechanism of the modulus variation. It is concluded that the first drying of the concrete system results in some irreversible changes in the structure of the hardened cement paste.

     

Heparin improves oxygenation and minimizes barotrauma after severe smoke inhalation in an ovine model

Inhalation injury is one of the main causes of mortality in burn victims. The tracheobronchial epithelium sloughs and combines with a protein rich exudate to form casts of the airways that can lead to obstruction. We studied the effects of a continuous infusion of heparin on the acute pulmonary injury that occurs after smoke inhalation injury in sheep. Twelve ewes with vascular catheters received a standardized smoke inhalation injury and mechanical ventilation according to protocol for 72 hours. The heparin group (n = 6) received a 400 unit per kilogram bolus of heparin followed by a continuous infusion to maintain the activated clotting time between 250 to 300 seconds. The control group (n = 6) received a saline solution vehicle. Hemodynamics, blood gases and plasma samples for conjugated dienes were taken every six hours. At necropsy, pulmonary tissue was collected for histologic findings, polymorphonuclear neutrophil leukosequestration, wet-to-dry weight ratios and conjugated dienes. PaO2 to FIO2 ratios were improved in the heparin group compared with the control group at 12 to 72 hours after injury, and peak airway pressures were higher in the control group compared with the heparin group. Positive end expiratory pressure requirements were higher in the control group compared with the heparin group. There were significantly fewer airway tracheobronchial casts as determined by our tracheobronchial casts scoring system (2.4 +/- 0.4 versus 0.67 +/- 0.21) and confirmed by histologic examination. Pulmonary blood-free wet-to-dry weight ratios were higher in the control group compared with the heparin group (6.4 +/- 0.5 versus 5.2 +/- 0.1; p < 0.05). There were no differences in pulmonary tissue or plasma conjugated dienes; likewise, pulmonary leukosequestration was unaffected by heparin. Heparin decreases tracheobronchial cast formation, improves oxygenation, minimizes barotrauma and reduces pulmonary edema in an ovine model of severe smoke inhalation injury. Heparin does not reduce oxygen free radical activity after smoke inhalation injury.     

No-slump concrete with fine sand and clay

The paper briefly reviews the effects of some deleterions materials on the strength of roller compacted and no slump concrete. The effects of fine sand and differing quantities of kaolinitic clay on the strength of no-slump concrete are reported. It is concluded that the use of fine sand caused a strength reduction in the no-slump concrete of about 22%. Further, the addition of 1% kaolinite resulted in a marked reduction in strength of the no-slump concrete. This reduction in strength is attributed, predominantly, to the interference of cement hydration due to the presence of the clay. However, further loss in strength of no-slump concrete due to the addition of kaolinite up to 10% of the total weight of the aggregate inclusive of clay seems to be a function of the overall increase in the surface area of the aggregate and a consequent increase in the water-cement ratio of the concrete. It is recommended that water curing of no-slump concrete containing silt and clay is very important for the proper strength development.