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Biomedical subjects

J Norris

Publications and source records attributed to J Norris.

At least 73 records · Page 4Linked to original sources
PubMed1986

Structure of Rhodopseudomonas sphaeroides R-26 reaction center.

The molecular replacement method has been successfully used to provide a structure for the photosynthetic reaction center of Rhodopseudomonas sphaeroides at 3.7 A resolution. Atomic coordinates derived from the R. viridis reaction center were used in the search structure. The crystallographic R-factor is 0.39 for reflections between 8 and 3.7 A. Validity of the resulting model is further suggested by the visualization of amino acid side chains not included in the R. viridis search structure, and by the arrangements of the reaction centers in the unit cell. In the initial calculations quinones or pigments were not included; nevertheless, in the resulting electron density map, electron density for both quinones QA and QB appears along with the bacteriochlorophylls and bacteriopheophytins. Kinetic analysis of the charge recombination shows that the secondary quinone is fully functional in the R. sphaeroides crystal.

Bacterial Proteins↗
PubMed1986

Teaching communication skills: effects of two methods of instruction and selected learner characteristics.

Performance outcomes were compared for groups of students (N = 147) randomly assigned to role play or lecture instruction for learning basic communication skills. These students also differed on the attributes of learning style and traditional-nontraditional status. Analysis of variance with age as a covariant was used in a factorial design to compare performance of the various subgroups on objective tests at two time intervals and on instructor ratings of students' skills on four dimensions of communication in process recordings of actual nurse-patient interactions. Significant (p = less than .05) differences were demonstrated as follows: the field-independent learning style group had higher mean scores on objective tests than did the field-dependent group, and the nontraditional group (older with prior academic degrees and life experience) had higher mean scores on the initial objective test and on instructor rated process recordings for the dimensions of caring, concreteness and empathy than did the traditional BSN student group in the sample. Differences in student evaluation ratings of the instructional method which were significant (chi 2 p = less than .05) included: role-play students indicated greater interest, active involvement and preference for the method, and lecture students indicated greater confidence that the method met the objectives and that they understood the material although no differences in overall mean performances were demonstrated. Interactive effects and the implications of the study findings are discussed.

Adult↗
PubMed1985

Characterization of bacterial photosynthetic reaction center crystals from Rhodopseudomonas sphaeroides R-26 by X-ray diffraction.

An orthorhombic crystal form (P2(1)2(1)2(1)) of the reaction center from the photosynthetic bacterium Rhodopseudomonas sphaeroides R-26 has been characterized. The crystals were grown from polyethylene glycol; the unit cell dimensions are a = 142.2 A, b = 139.6 A, and c = 78.7 A; and they contain one reaction center in each crystallographic asymmetric unit. The crystals diffract to at least 3.0 A resolution, and are suitable for detailed structural studies.

Bacterial Proteins↗
PubMed1985

Self-esteem disturbance.

Defining characteristics for self-esteem disturbance are examined for inter-rater reliability based on clinical observations and interviews by two clinical specialists. A tentative conceptual model and three distinct types of self-esteem disturbance are proposed for further research based on review of the literature and the clinical data.

Adolescent↗
PubMed1977

Sex differences in Necturus urinary bladders.

We describe morphological sex differences in urinary bladders of the urodele amphibian Necturus maculosus. The mucosal epithelial cells of bladders from males were tall and contained considerable PAS-positive material. In scanning electron micrographs of the mucosal surface, epithelial cells from male bladders were well demarcated and were capped with microplicae or with long cilia. The mucosal epithelial cells of bladders from females were low and contained only a small amount of PAS-positive material; in scanning electron micrographs cell boundaries could not be distinguished and no cilia or microplicae were present. Bladders from males had higher transepithelial potential difference and lower water content than bladders from females. Urine analyses were not significantly different in the two sexes. It is suggested that response to androgens in the male accounts for the observed differences.

Animals↗