Parathyroid arteriography

Parathyroid arteriography and venous sampling for parathormone are the best techniques presently available for preoperative localization of hyperplastic and neoplastic parathyroid tissue. Inaccuracy of the technique, risk of complications, and relatively high cost make the routine use of arteriography and venous sampling inappropriate. They are, however, a useful preoperative adjunct in the patient who has undergone a previously unsuccessful neck exploration.     

MyoD and Myf-5 differentially regulate the development of limb versus trunk skeletal muscle

The myogenic progenitors of epaxial (paraspinal and intercostal) and hypaxial (limb and abdominal wall) musculature are believed to originate in dorsal-medial and ventral-lateral domains, respectively, of the developing somite. To investigate the hypothesis that Myf-5 and MyoD have different roles in the development of epaxial and hypaxial musculature, we further characterized myogenesis in Myf-5- and MyoD-deficient embryos by several approaches. We examined expression of a MyoD-lacZ transgene in Myf-5 and MyoD mutant embryos to characterize the temporal-spatial patterns of myogenesis in mutant embryos. In addition, we performed immunohistochemistry on sectioned Myf-5 and MyoD mutant embryos with antibodies reactive with desmin, nestin, myosin heavy chain, sarcomeric actin, Myf-5, MyoD and myogenin. While MyoD(-/-) embryos displayed normal development of paraspinal and intercostal muscles in the body proper, muscle development in limb buds and brachial arches was delayed by about 2.5 days. By contrast, Myf-5(-/-) embryos displayed normal muscle development in limb buds and brachial arches, and markedly delayed development of paraspinal and intercostal muscles. Although MyoD mutant embryos exhibited delayed development of limb musculature, normal migration of Pax-3-expressing cells into the limb buds and normal subsequent induction of Myf-5 in myogenic precursors was observed. These results suggest that Myf-5 expression in the limb is insufficient for the normal progression of myogenic development. Taken together, these observations strongly support the hypothesis that Myf-5 and MyoD play unique roles in the development of epaxial and hypaxial muscle, respectively.     

Rowlinson's concept of an effective hard sphere diameter

Attention is drawn to John Rowlinson's idea that the repulsive portion of the intermolecular interaction may be replaced by a temperature-dependent hard sphere diameter. It is this approximation that made the development of perturbation theory possible for realistic fluids whose intermolecular interactions have a steep, but finite, repulsion at short separations.     

Assessment of conformational parameters as predictors of limited proteolytic sites in native protein structures

Despite the importance of limited proteolysis in biological systems it isoften difficult to rationalize why a proteinase hydrolyses a particularbond, given a simple sequence specificity alone. Understanding of thestructural properties limiting the proteolysis represents a first step onthe pathway to control and manipulation of this phenomena. An expanded setof nick-sites in proteins of known tertiary structure, cut by both narrowand broad specificity proteinases, has been generated yielding a robustdata set of strictly limited sites. A critical evaluation of an expandedset of conformational parameters revealed a strong correlation with limitedproteolytic sites, although they are only modest predictors in isolation.The overall predictive power is significantly improved when theconformational parameters are combined in a weighted predictive scheme thatpermits their relative importance to be compared via a Metropolis searchprotocol. A subset of the parameters performs equally well demonstratingthe key determinants of susceptibility. The derived predictive algorithmhas been made available via the internet. Its utility for predicting othersurface-correlated features is also discussed.     

All-source bidding: Extending integrated competition to utility resource procurement

When facing a resource need, utilities should use all-source bidding to help identify the highest value resources to procure. By soliciting proposals from suppliers across all resource options, the utility applies to procurement the same important principles that guide integrated resource planning. All-source bidding is not new, but many utilities have not used it. This article explains how all-source bidding works, describes the benefits, and offers practical recommendations for utilities and utility regulators.     

Relationship between self-report and log data estimates of information system usage

Self-report estimates of frequency and duration of computer use are used extensively in research related to computer and information systems acceptance. Despite concerns that self-report estimates are inferior to computer log data there is a paucity of research investigating the relationship between self-report and log data measures of computer use. The present study compared self-report estimates and six months of electronic log data for 62 health care workers using a new Community Services Information System. There were moderate to strong correlations between the self-report and electronic log estimates of frequency and duration of system use. Self-report estimates were relatively accurate in that they were quite similar in magnitude to log data values. The merits of combinations of frequency and duration data (composites) were also assessed.     

Intellectual styles: A comparison of factor structures in gifted and average children and adolescents.

Describes and compares structures of intellectual activity in gifted and average children, as found in 2 studies. In Study 1, 307 gifted and 192 average children in Grades 5–10 gave self-reports about their curiosity and about their frequency of and attitudes toward daydreaming. Demographic information and IQ scores were obtained from school records. The intercorrelations of these variables were factor analyzed for the gifted and average groups separately. Results indicated the presence of independent intellectual power (general intelligence) and intellectual style (daydreaming and curiosity) factors in each group. Comparisons of the analyses indicate considerable similarity in the structures of intellectual style in the gifted and average groups. These results were cross-validated in Study 2, dealing with self-reported daydreaming in 98 gifted and 105 average children in Grades 9–12. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)