A strident public impatience drives true change. Interview by Carolyn Dunbar

Sunquest's president and chief executive officer, Sidney Goldblatt, M.D., says the inefficient way information is shared in healthcare is "stupid" and wouldn't be tolerated in other industries. Until the public becomes impatient and strident about flagrant waste and begins to demand most cost-effective methods in healthcare, true change will take a lot longer.     

The preparation and properties of some urethane foams from castor oil and elaidinized castor oil

Summary The preparation and properties of two series of castor oil urethane foams, one from castor oil and the other from elaidinized castor oil, were investigated. The first series of foams was made from prepolymers containing 60% of castor oil prepared at increasing temperature levels to vary the degree of crosslinking in the final foams. These foams had lower tensile strengths than observed for a previously prepared foam of 60% castor oil and did not show significant differences in water resistance as crosslinking varied. They were increased nearly 100% in compressive strength with increased crosslinking and had very good shrinkage characteristics as values of only 1 to 2% were obtained. A second series of foams was prepared from 50, 60, 70, and 80% of elaidinized castor oil to compare with foams from a similar series from castor oil. This series of foams of 50 to 80% elaidinized castor oil contents was similar in density (1.7 to 6.7 lbs./cu. ft.), had improved shrinkage characteristics (11, 1, 3, and 4%, respectively), showed increased compressive and tensile strengths (up to 12.1 p.s.i. at 50% compression modulus and 34.7 p.s.i. ultimate tensile for the 60% foam formulation), and had better water-resistance properties (411 to 155%vs. 515 to 170% water absorption) than the analogous foams from castor oil. In general, humid aging only slightly affected the values obtained for the foams and was significant in only a few instances,e.g., decreased tensile in the elaidinized castor oil series. Thus increasing crosslinks in the foam apparently did not improve water resistance but did improve shrinkage characteristics in addition to some increased strength properties, as would be anticipated. Foams from elaidinized castor oil, while similar in density and foaming characteristics to analogous foams from castor oil, exhibited less shrinkage and improved water-resistance. Presented at the 50th Annual Meeting of the American Oil Chemists' Society, New Orleans, La., April 20–22, 1959. Ono of the laboratories of the Southern Utilization Research and Development Division, Agricultural Research Service, U. S. Department of Agriculture.     

Assay of aflatoxin in peanuts and peanut products using acetone-hexane-water for extraction

A quantitative method is described for the assay of aflatoxin in peanut products. The procedure involves extraction of aflatoxin from the sample with a homogeneous acetone-hexane-water solvent mixture followed by purification of the extract by phasic extraction of the aflatoxin with aqueous sodium chloride and then with chloroform. The purified chloroform extract is analyzed by thin-layer chromatography by comparison of the intensity of fluorescence of any aflatoxin with the intensity of a known standard. The aflatoxin analyses of peanuts were found to be very variable due to sampling, and this variability has been greatly reduced by finely grinding and thoroughly mixing 2 kg of the sample before removal of an aliquot for assay. The method is sensitive to approximately 2 parts per billion. Honorable mention, Bond Award competition. Presented at AOCS Meeting, Chicago, Illinois, October, 1964. So. Reg. Res. Lab., New Orleans, Louisiana, one of the laboratories of the So. Utiliz. Res. and Dev. Div., ARS, USDA.     

A modal proof theory for final polynomial coalgebras

An infinitary proof theory is developed for modal logics whose models are coalgebras of polynomial functors on the category of sets. The canonical model method from modal logic is adapted to construct a final coalgebra for any polynomial functor. The states of this final coalgebra are certain “maximal” sets of formulas that have natural syntactic closure properties.

The syntax of these logics extends that of previously developed modal languages for polynomial coalgebras by adding formulas that express the “termination” of certain functions induced by transition paths. A completeness theorem is proven for the logic of functors which have the Lindenbaum property that every consistent set of formulas has a maximal extension. This property is shown to hold if the deducibility relation is generated by countably many inference rules.

A counter-example to completeness is also given. This is a polynomial functor that is not Lindenbaum: it has an uncountable set of formulas that is deductively consistent but has no maximal extension and is unsatisfiable, even though all of its countable subsets are satisfiable.     

Chromatostrip analysis of fatty acid derivatives

Chromatostrips provide a rapid and convenient method of examination of samples by spot tests and by ascending or descending chromatography. Ascending chromatography for the examination of mixtures is carried out on 12×140-mm. glass strips coated with 5% starch-bonded silicic acid, while descending chromatography is done on 12×200-mm. strips. The 5% starch-bonded silicic acid coatings are resistant to normal handling, may be marked with a soft lead pencil, and may be stored indefinitely for reference. Three detection systems are employed: fluorescent minerals for conjugated unsaturates, fluorescein-bromine for unsaturates, and 2′,7′-dichlorofluorescein for all types of compounds. Positive tests result in characteristic spots when observed under normal or ultraviolet illumination. This permits the classification of components, after separation on the chromatostrips, into the groupings of conjugated unsaturated, unsaturated (or easily brominated), and saturated compounds.     

Efficacy of gene testing for von Hippel-Lindau disease

OBJECTIVE: To determine the efficacy of genetic testing of individuals presenting with features possibly indicative of von Hippel-Lindau (VHL) disease, regardless of other relevant family and clinical details. SETTING AND PARTICIPANTS: Between September 1994 and December 1997, 16 unrelated individuals were referred to Genetic Services of Western Australia by local clinicians and by similar genetic services in other States, for VHL gene mutation analysis because of clinical manifestations suggestive of the diagnosis. METHODS: The subjects were investigated by screening for mutations in the polymerase chain reaction products of the three VHL gene exons using single-stranded conformational polymorphism analysis (SSCP). If no mutations were detected the exons were sequenced, and if no variations were found DNA was examined by Southern analysis for germinal rearrangements. RESULTS: Mutations in the VHL gene were detected in eight of 16 individuals (50%), including 3 individuals with no family history suggestive of VHL disease. Five mutations were detected by SSCP, two by gene sequencing and one by Southern analysis. Each mutation occurred only in a single family and three had not been previously reported. CONCLUSION: Genetic screening of individuals presenting with clinical features suggestive of VHL facilitates confirmation of the diagnosis, accurate genetic counselling and surveillance of at-risk family members. The necessity for costly and time-consuming screening programs can be reduced and screening directed at those carrying the mutation. Our low stringency criteria are justified for screening for VHL mutations.     

The reaction of mercaptoacetic acid with methyl linoleate and linoleic acid

The reaction of mercaptoacetic acid with methyl linoleate and with linoleic acid was investigated. The reaction proceeded at low and erratic rates, with and without catalysts, such as peroxides at various temperatures, but could be accelerated by use of a large excess of mercaptoacetic acid. Addition of 1 mole of mercaptoacetic acid to 1 mole of methyl linoleate resulted in a product containing about 40% of mono-adduct. Ozonolysis of the purified mono-adduct yielded approximately equimolar quantities of caproic and azelaic acids, indicating that addition occurred about equally at the 9,10- and 12,13-ethylenic bonds. The dicarboxylic acid and the dimethyl ester of the mono-adduct and the tricarboxylic acid and trimethyl ester of the di-adduct of linoleic acid and mercaptoacetic acid were prepared, and the infrared spectra and some physical and chemical characteristics of these products were determined. The infrared spectra of the reaction products were obtained and correlated with functional groups which give rise to them. Bands at about 7.8 and 8.8 μ, commonly observed in long chain acids and esters and ascribed to C−O vibrations, are intensified in the sulfur-containing reaction products, suggesting characteristic absorption of C−S compounds at almost identical wavelengths. The formation of adducts was accompanied by a high degree of isomerization of the unreacted ethylenic bonds from thecis to thetrans form both in the mono-adduct and in unreacted methyl linoleate. The methyl linoleate recovered contained about 12% diene conjugation, but catalytic quantities of mercaptoacetic acid were not effective in inducing conjugation.