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The work assessed the use of shear viscosity at 0.1 s-1 ( [Formula: see text] ) as a parameter to detect changes in the conditioning and dewatering of digestates. Total and soluble fractions of organic matter of digestate samples before and after storage were also assessed in regards to their conditioning and dewatering performance. Digestate from a conventional mesophilic anaerobic digestion (CMAD) and advanced anaerobic digestion (AAD) plants were used. Linear regression and correlation analysis of 29 different parameters showed that soluble and total fractions of organic matter (Norg, Sc, Sp, Tp, TKN/COD, tCOD and sCOD) during plant operation and storage conditions correlated (r between 0.80 and 0.99) with the variation in polymer dose, floc strength and CST of conditioned digestate samples. The variations occurred within the content of soluble and total fractions of organic matter, and showed to correlate with both conditioning requirements and the variation in [Formula: see text] . The work concluded that [Formula: see text] measurements of unconditioned digestate samples have the potential to be used as a parameter to monitor conditioning requirements during digestate storage or during process changes. It was found important to analyse soluble and total fractions of organic matter in order to understand the changes in [Formula: see text] within specific process conditions.

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This study investigates the use of Fourier transform near infrared (FT-NIR) spectroscopy combined with principle components analysis (PCA) and partial least squares regression (PLS-R) as part of a possible process monitoring system for sewage sludge anaerobic digesters. The ability of FT-NIR with PCA to distinguish between different stages of the AD process was investigated, it was found that waste activated sludge (WAS), primary, feed (Primary:WAS 70:30) and digested sludge were distinguishable from each other using this technique. PLS-R was used successfully to track differing proportions of primary:WAS in feedstocks of 5% total solids (Coefficient of Efficiency (CE) = 0.93). The study also looked at the ability of reflectance mode NIR spectroscopy to track process parameters important for stability. Temperature and organic loading rate variations were employed to stress the digesters. Predictive models were produced for volatile fatty acids (VFA), bicarbonate alkalinity (BA) and total and volatile solids (TS and VS) and independently validated for each digester. The models were able to track the relevant process parameters: TS (CE = 0.75), VS (CE = 0.75), BA (CE = 0.71), and VFA (CE = 0.69). This technique could be used to improve the performance of sewage sludge anaerobic digesters.

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In 1997 and 1998, Cry9C susceptibility baselines were established for field-collected populations of European corn borer, Osrinia nubilalis (Hubner), and southwestern corn borer, Diatraea grandiosella Dyar. Bioassay of neonate European corn borer larvae of 16 colonies collected from the midwestern United States indicated LC50 values ranging from 13.2 to 65.1 ng of Cry9C protein per square centimeter. Neonate European corn borer LC50 values ranged from 46.5 to 214 ng/cm2. Neonate larvae of three colonies of southwestern corn borer collected from the southern and southwestern United States exhibited LC50 values from 16.9 to 39.9 ng of Cry9C protein per square centimeter. Southwestern corn borer neonate LC90 confidence limit values ranged from 40.3 to 157 ng of Cry9C protein per centimeter. The most sensitive southwestern corn borer colony was collected from the Mississippi delta exhibiting an LC50 value of 22.6 ng of Cry9C per cm2 and also displayed the widest LC0 confidence limits of 40.3-94.8 ng of Cry9C per cm2. Geographic baseline susceptibility data establishes the natural genetic variation and provides the foundation for future testing of insect populations exposed to increased use of Bacillus thuringiensis-based crops. Insect resistance management and stewardship of Cry9C will rely upon baseline data for the validation of discriminating dose assays for European corn borer and southwestern corn borer.

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OBJECTIVE: To search for cosegregation of a change in specific blood cells with either the hypertension or the hyperactivity phenotype in spontaneously hypertensive rats (SHR), Wistar-Kyoto (WKY) rats and two new inbred strains. DESIGN AND METHODS: Standard hematological procedures were used to examine erythrocytes, leukocytes and platelets in blood drawn from adult SHR, WKY rats and the two new inbred strains of rats. RESULTS: The hypertensive strains exhibited significant erythrocytosis, microcytosis, lymphocytosis and monocytosis relative to the normotensive strains. The hyperactive strains exhibited significant neutrophilia and increased platelet count relative to the non-hyperactive strains. CONCLUSION: Not all of the differences in blood cells described originally in SHR versus WKY rats were associated with the inheritance of hypertension. The changes in the lymphocytes and in the erythrocytes should be examined as possible factors in the pathophysiology of hypertension.

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The medical technology program at the University of Vermont was modified in 1972 to create a 2 + 2 integrated curriculum with specialty options progressing that associate degree to baccalaureate degree. This design allows the fundamentals acquired in the associate degree curriculum of the medical laboratory technician (MLT) to serve as a practical and theoretical foundation that can be expanded upon in the baccalaureate degree curriculum of the medical technologist (MT). Options in the baccalaureate degree curriculum are generalist, specialist in clinical chemistry, in hematology, and in clinical microbiology. The design of this program provides a response to the changing role of the clinical laboratory practitioner.

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Seventeen temperature-sensitive mutants of bacteriophage SH-133 have been isolated following mutagenesis with UV-light, nitrosoguanidine, and ethyl methanesulfonate. The mutants were classified into 15 complementation groups according to their ability to complement each other at 32 degrees C, the nonpermissive temperature. Each mutant was studied with regard to the relationship between its ability to multiply in heterotrophically (H-) and autotrophically (A-) grown Pseudomonas facilis cells. At 27 degrees C, the permissive temperature, the plaque-forming ability of the 17 mutants and wild-type phage was reduced 10-fold in A-grown cells. At 32 degrees C, mutants belonging to 10 groups exhibited identical levels of multiplicity-dependent leak under both modes of growth. However, the infection of A-grown cells by mutants belonging to the remaining five groups resulted in as much as 500-fold inhibition of multiplicity-dependent leak when contrasted with the infection of cells grown heterotrophically. These observations indicate that the expression of five SH-133 phage cistrons is defective when multiplication proceeds under autotrophic metabolism. Seven mutants were found to differ from the wild-type phage with regard to thermal stability at 56 degrees C which suggests that they possess altered structural proteins. Four of the seven thermosensitive mutants exhibited reduced levels of multiplicity-dependent leak in A-grown cells. The data suggest that the reduction in plaque-forming ability of SH-133 in A-grown cells is caused by a defect in the expression of specific phage structural components.

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