PubMed Health⌕ Search

Biomedical subjects

J B Speyer

Publications and source records attributed to J B Speyer.

4 recordsLinked to original sources

The impact of formalization, role conflict, role ambiguity, and communication quality on perceived organizational innovativeness in the Cancer Information Service.

Organizational members' levels of perceived innovativeness represent an insider's viewpoint of the organization's overall approach to innovation. This study tested a model of the impact of formalization, role ambiguity, role conflict, and communication quality on perceived organizational innovativeness in the Cancer Information Service. Data were gathered from self-report questionnaires completed by organizational members (n = 86) within the Cancer Information Service, a geographically dispersed federal government health information program that was implementing innovative intervention strategies related to disseminating health information to the public. Results indicated that although the predicted model provided a good overall fit to the data, there were some problematic paths. A revised model is offered to reconceptualize the relationships among role conflict, role ambiguity, and communication quality. These results are discussed in terms of their implications for managers and scholars who hope to understand the factors that contribute to perceptions of innovativeness in the new organizational forms emerging in the health service arena. These data suggest that formalization makes an important contribution to innovation in the highly uncertain world of new organizational forms.

Attitude of Health Personnel↗

Anisotropic 2H NMR spin-lattice relaxation in L alpha-phase cerebroside bilayers.

A series of 2H NMR inversion recovery experiments in the L alpha phase of the cerebroside N-palmitoylgalactosylsphingosine (NPGS) have been performed. In these liquid crystalline lipid bilayers we have observed substantial anisotropy in the spin-lattice relaxation of the CD2 groups in the acyl chains. The form and magnitude of the anisotropy varies with position in the chain, being positive in the upper region, decreasing to zero at the 4-position, and reversing sign at the lower chain positions. It is also shown that addition of cholesterol to the bilayer results in profound changes in the anisotropy. These observations are accounted for by a simple motional model of discrete hops among nine sites, which result from the coupling of two modes of motion--long-axis rotational diffusion and gauche-trans isomerization. This model is employed in quantitative simulations of the spectral line shapes and permits determination of site populations and motional rates. These results, plus preliminary results in sphingomyelin and lecithin bilayers, illustrate the utility of T1 anisotropy measurements as a probe of dynamics in L alpha-phase bilayers.

Cerebrosides↗

Magnetic orientation of sphingomyelin-lecithin bilayers.

Phospholipid bilayers consisting of a 60:40 mixture of N-palmitoylsphingomyelin and dimyristoylphosphatidylcholine orient in a strong magnetic field. The orientation is easily observed in 31P- and 2H-nuclear magnetic resonance spectra where the intensity of the perpendicular edges of the powder lineshapes are enhanced. The lineshapes indicate that the long axis of the molecule is perpendicular to the magnetic field.

Dimyristoylphosphatidylcholine↗