Distribution and identification of the fatty acids from the coho salmon,Oncorhynchus kisutch (Walbaum)

To study the fatty acids of the coho salmon, entire fish were homogenized and the total lipids extracted with methanol-chloroform. The fish ranged in size from 75 to 85 mm total length and contained from 2.1%–6.9% lipid in the tissues. Methyl esters of the fatty acids were produced with anhydrous methanol and HCl. Qualitative identification of the fatty acid methyl esters was accomplished by gas-liquid chromatography. Thin layer silver nitrate-silicic acid plates were used to separate the component methyl esters according to the number of double bonds. Location of the ethylenic groups of the unsaturated fatty acid methyl esters was established by reductive ozonolysis and identification of the aldehydes and aldehyde-esters produced. The number of carbons in the unsaturated fatty acid methyl esters was determined by hydrogenation of each of the fractions. Fatty acids found in the highest concentrations were: 16∶0, 16∶1, 18∶0, 18∶1, 18∶4, and 22∶6. Fatty acids 16∶0, 18∶1, 18∶2, 20∶5, and 22∶6, differed markedly from concentrations found in tubificid worms, the exclusive diet of the fish during the experiment. Technical Paper No. 2059, Oregon Agricultural Experiment Station Work supported in part by research Grant No. EF105, U.S.P.H.S.     

Minimizing Total Tardiness: A Case Study in an Autoparts Factory

The application of heuristic procedures for solving a real scheduling problem that arises in an autoparts factory is reported in this paper. Due to the characteristics of the environment, the measure of performance considered is the minimization of the total tardiness of the jobs. The original problem is reduced to the single machine scheduling problem, and the dispatching rules EDD (earliest due date), SPT (shortest processing time), and the PSK algorithm are used to obtain approximate solutions. Computational tests and a comparison with the usual schedule are presented.     

Drug effects on cerebral blood flow in the baboon model--acetazolamide and nimodipine

The sensitivity of the baboon model under anaesthesia for single photon emission computed tomography (SPECT) of the brain with 99mTc-HMPAO, as recently developed by us to study cerebral blood flow patterns, was investigated using drugs that are known to increase cerebral blood flow, e.g. acetazolamide, the carbonic anhydrase inhibitor and nimodipine, the calcium channel blocker. Increases in cerebral blood flow for both acetazolamide and nimodipine were observed that correspond well with other studies. Statistically significant regional specificity was noted for acetazolamide and nimodipine. Interestingly a combination of these drugs did not enhance cerebral blood flow but rather decreased it in comparison with the individual drug responses. The results were correlated with arterial blood pressure, heart rate, pCO2 and pO2. A blood pressure decrease was noted for both drugs, while acetazolamide had a marked influence on pO2. The results indicate that the baboon model is sensitive for evaluation of drug effects on cerebral blood flow.     

Structure and mechanical properties of unidirectionally solidified Fe-Cr-C and Fe-Cr-X-C alloys

In this work four different microstructures were obtained by unidirectional solidification of Fe-Cr-C eutectic alloys. Conditions for zone coupled growth were determined in alloys containing approximately 30 wt pct chromium. Furthermore, mechanical testing indicated that the maximum strength was exhibited by Fe-30Cr-C alloys with cerium or titanium additions. These alloys had the largest volume fraction of eutectic fibers and their ultimate tensile strength was of the order of 3250 MPa. Correlations between the rate of crystal growth(u) and fiber spacing (λ) or tensile strength(Rm) were found and an expression of the typeRm = Aλ^-b2 was obtained whereb ₂ varied between 0.283 and 0.685. Finally, manganese or chromium (35 wt pct Cr) additions did not lead to appreciable improvements in composite strength for this alloy system.     

Effect of a rice bran fiber diet on serum glucose levels of diabetic patients in Brazil

Eleven diabetic patients: 5, type 1 and 6, type 2 received a low-fiber diet (I) during 1 week and during the next 7 days the same diet, enriched with 40 g of fiber (30.6% insoluble and 11.7% soluble components) from rice bran (II) per day. Results showed that mean fasting and postprandial serum glucose levels were reduced, but values of high fiber diet were significantly lower (p < 0.001) than that of the lower fiber diet. For all patients, the high-fiber diet increased fecal weight. This increase was due to the fiber excreted, rather than water retained. There was no relationship between the increase in fiber intake and its fecal excretion. Sucrose and raffinose were found in the bran, but not in the feces. Lactose was present in the stools of the patients receiving enriched diet.