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PubMed1991

Self-assessment and learning through GOSCE (group objective structured clinical examination).

The objective structured clinical examination (OSCE) was modified to serve as a means of self-assessment and learning, rather than as an examination. The main modifications were to adapt it for use by small groups instead of individuals, and to provide a correct answer or other feedback at each station. The resulting group OSCE (GOSCE) was used as an introductory session in two residential refresher courses for general practitioners. The 300 participants rated it highly as a method of self-assessment and as an enjoyable social event. Four potential applications of the GOSCE are suggested: as an assessment instrument for formative and informal summative assessment, as a resource for learning about interpersonal and interprofessional relationships, and as a framework for problem-based short courses.

Education, Medical, Graduate↗
PubMed1979

[Restoring the continuity of severed peripheral nerves. Indications and surgical technics].

The detailed literature is critically examined, especially with regard to the questions of the time of the operation, technique of the intervention, use of transplantation, suture under tension, etc. The author recommends the following operating tactics: (I) Smoothly separated nerves without any defects or larger side-injuries are subject to primary care. Mono- to oligofascicular nerves are loosely coapted by epineural sutures; the protruding contents are not excised. For polyfascicular nerves one uses endofascicular guiding sutures and coaptation by epineural sutures. In case of a clear group structure, interfascicular coaption is used. (2) Early secondary care according to plan gets to the stumps from the healthy material and uses interfascicular transplantation for every tension occurring. In case of polyfascicular nerves without group structure, the corresponding sectors are connected with each other. (3) The late secondary care follows the rules for the early secondary care. (4) Re-operations are carried out if regeneration does not set in, testing is mainly carried out by means of the Hoffmann-Tinel sign. Sometimes intraneural neurolysis will be sufficient in these cases; more often than not, parts of the whole cross-section must be resected or bridged again by transplantation.

Adult↗
PubMed2000

Persistence of the benefits of a structured psychiatric intervention for breast cancer patients with lymph node metastases.

The aim of this study was to investigate the persistence of clinical effectiveness of a 5 week structured group intervention program for Japanese breast cancer patients. A total of 47 patients with breast cancer completed the full program. The results of the Profile of Mood States (POMS) scores were compared before, immediately after, and 6 months after the intervention program. As analysed by POMS scores, the clinical effectiveness of a structured group intervention program persisted for 6 months for patients without nodal metastases. In contrast, the intervention program did not show a lasting effect for patients with nodal metastases. This study demonstrated the short-term effectiveness of structured interventions among Japanese cancer patients, but persistence of the effects of intervention was found only among patients without nodal metastases. For patients with nodal metastases, additional intervention would be needed.

Adult↗
PubMed2004

Photoelectron spectroscopy and density functional theory of puckered ring structures of Group 13 metal-ethylenediamine.

The ethylenediamine (en) complexes of Al, Ga, and In atoms were prepared in laser-vaporization supersonic molecular beams and studied with pulsed field ionization zero electron kinetic energy photoelectron spectroscopy and density functional theory. Several conformers of each metal complex are obtained by B3LYP calculations, and a five-membered cyclic structure is identified by combining the experimental measurements and theoretical calculations. Adiabatic ionization potentials, vibrational frequencies, and bond dissociation energies are determined for the ring structure. The ionization potentials of the Al, Ga, and In species are measured to be 32 784 (5), 33 324 (5), and 33 637 (7) cm(-1), respectively, and metal-ligand dissociation energies of the ionic and neutral complexes are calculated to be 60.2/16.2 (Al(+)/Al), 55.5/13.0 (Ga(+)/Ga), and 50.0/11.4 (In(+)/In) kcal mol(-1). Metal-ligand stretch and bend as well as a number of ligand-based vibrations are measured. Harmonic frequencies and anharmonicities of the M(+)-N (M=Al,Ga,In) stretch are determined for all three M(+)-en ions and the C-C-N bend of Ga(+)-en and In(+)-en. In comparison to monodentate methylamine, the bidentate binding of ethylenediamine leads to a significantly lower ionization potential and higher metal-ligand bond strength of the metal complexes.

Aluminum↗
PubMed2004

Group-theoretic structure in the sequential flow of sensory experiences.

The hypothesis presented here is that in a given person, the overall configuration of sensory variables at any given moment, i.e. everything that the person is seeing, hearing, etc., can be treated as belonging to an infinite sequence of such momentary configurations, with the sequence being generated by a particular mathematical group. The ideas behind this are as follows. If a person's various moment-to-moment sensory experiences can all be described within the same coordinate system, then they can be treated as objects that sequentially transform into one another. If they are also encoded by brain events, then the person's own encounters with this encoding, e.g. when participating in brain-stimulation experiments, amount to instances where a given sensory experience inevitably follows other sensory experiences occurring in a specific sequence. For example, a person's visual encounters with certain equipment-settings might always be followed by a particular visual hallucination. If there exist sequences like this for any given momentary sensory experience, then these collectively form the person's sensory code, as it would be encountered from the person's own perspective. The person's ongoing flow of sensory experiences may then be treated as part of the infinite sequence implied by the various code-conserving ways in which sensory experiences can flow from one to the next. If this sequence can be generated by a finite number of code-conserving segments that transform into each other and link together end to end, then a person's full range of sensory experiences can be defined in group-theoretic terms.

Adaptation, Physiological↗
PubMed1990

Structure-activity relationship of yohimbine and its related analogs in blocking alpha-1 and alpha-2 adrenoceptors: a comparative study of cardiovascular activities.

We investigated the selectivities and structure requirements for alpha-1 and alpha-2 adrenoceptor blocking activities of yohimbine (YO) and its 12 related analogs, such as beta-yohimbine (beta-YO), dihydrocorynantheine (DHC) and (-)indoloquinolizidine ((-)IQ). The affinity of YO analogs to alpha-adrenoceptor was assessed by measuring their blockade of pressor responses to epinephrine in pithed rats. Among YO structure groups, the potency order was YO greater than DHC = beta-YO greater than geissoschizine methylether greater than 14 beta-hydroxy YO greater than 14 beta-benzoyloxy YO (inactive). (-)IQ was slightly less potent than YO, but much stronger than (+)IQ. Among (+/-)IQ structure groups, the potency order was (+/-)IQ greater than (+/-)1,12b-trans-1-hydroxy IQ much greater than (+/-)1,12b-cis-1-hydroxy IQ (inactive). (+/-)Borrerine was active, but (+/-)desmethylborrerine was inactive. The alpha-1 blocking activities of the four compounds YO, beta-YO, DHC and (-)IQ, were assessed in experiments of pressor responses to methoxamine in pithed rats and contractile responses to methoxamine in the rat vas deferens. The potency order was (-)IQ greater than YO greater than DHC greater than beta-YO. Furthermore, the alpha-2 blocking activities of the four analogs were assessed in experiments of pressor responses to clonidine and inhibition of electrically driven cardioacceleration by clonidine, in pithed rats. The potency order was YO greater than beta-YO greater than (-)IQ greater than DHC. Based on the potency ratio between alpha-1 and alpha-2 blocking activities, DHC or YO was most selective for alpha-1 or alpha-2 subtype, respectively, among the four YO analogs.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic alpha-Antagonists↗
PubMed1999

Mode of physical activity and self-efficacy in older adults: a latent growth curve analysis.

A randomized controlled trial examined the effect of two physical activity modes on changes in self-efficacy over the course of a 12-month period in older, formerly sedentary adults (N = 174, M age = 65.5 years). Participants were randomized into either an aerobic activity group or a stretching and toning group. Structural equation modeling was employed to conduct multiple sample latent growth curve analyses of individual growth in exercise and physical self-efficacy over time. Results revealed a curvilinear growth pattern for both types of efficacy with increases occurring over the first 6 months followed by declines at the 6-month follow-up. There was a significant treatment by mean level growth interaction for exercise efficacy with both groups increasing over time, but the aerobic group evidenced a twofold increase in growth over the stretching group. Structural analyses indicated that frequency of exercise participation was a significant predictor of overall growth in efficacy, and improvements in fitness were only related to exercise efficacy growth in the stretching group. Findings are discussed in terms of social cognitive theory and further application of latent growth curve modeling to studies of physical activity effects in older adults.

Activities of Daily Living↗
PubMed1994

Platelet secretory phospholipase A2 fails to induce rabbit platelet activation and to release arachidonic acid in contrast with venom phospholipases A2.

The ability of platelet secretory phospholipase A2 (sPLA2) to induce platelet activation was investigated. sPLA2 (group II) contained in an activated platelet supernatant, as well as high concentrations of purified recombinant platelet sPLA2, failed to induce platelet activation. Furthermore, sPLA2 did not modify platelet activation induced by various agonists. The possible relationship between the failure of this enzyme to induce platelet activation and its origin (mammalian) or its structural group (group II) was then investigated, using pancreatic PLA2s (group I) and venom PLA2s from groups I, II and III. All venom PLA2s induced platelet activation that was accompanied by the liberation of arachidonic acid and was abolished by aspirin. In contrast, as observed for platelet sPLA2, enzymes from hog or bovine pancreas were unable to induce platelet activation even when used at high concentrations. Interestingly, PLA2 able to induce platelet activation efficiently hydrolyse phosphatidylcholine, while those inactive on platelets did not. Taken together, these results suggest that the catalytic activity of added PLA2 is necessary but not sufficient to induce platelet activation. Moreover, the ability of PLA2 to induce platelet activation is not related to its structural group (I, II, III) but rather to its origin (venom vs. mammalian) and capacity to hydrolyse phosphatidylcholine, the major phospholipid of the outer leaflet of the plasma membrane.

Animals↗
PubMed1982

Arylhydroxamic acid bioactivation via acyl group transfer. Structural requirements for transacylating and electrophile-generating activity of N-(2-fluorenyl)hydroxamic acids and related compounds.

The synthesis of a series of 12 N-(2-fluorenyl)hydroxamic acids, N-(2-fluorenyl)-N-hydroxyureas, and N-(2-fluorenyl)-N-hydroxycarbamates is reported. The compounds were evaluated for their ability to serve as substrates for a partially purified hamster hepatic arylhydroxamic acid N,O-acyltransferase preparation. Transacylating activity was measured spectrophotometrically with 4-aminoazobenzene as the acyl group acceptor, and electrophile-generating activity was quantified by the N-acetylmethionine trapping assay. Only the N-acetyl, N-propionyl, and N-methoxyacetyl derivatives exhibited relatively high levels of activity as measured by either of the assay methods. These results are generally consistent with previously reported conclusions regarding the steric and electronic characteristics of acyl groups that are required for activation by this enzyme system. N,O-Acyltransferase inactivation by N-hydroxy-2-acetamidofluorene depressed the bioactivation of the N-acetyl compound to a greater extent than either the N-propionyl or N-methyloxyacetyl derivative.

Acetyltransferases↗
PubMed2005

ERVK9, transposons and the evolution of MHC class I duplicons within the alpha-block of the human and chimpanzee.

The genomic sequences within the alpha-block (approximately 288-310 kb) of the human and chimpanzee MHC class I region contains ten MHC class I genes and three MIC gene fragments grouped together within alternating duplicated genomic segments or duplicons. In this study, the chimpanzee and human genomic sequences were analyzed in order to determine whether the remnants of the ERVK9 and other retrotransposon sequences are useful genomic markers for reconstructing the evolutionary history of the duplicated MHC gene families within the alpha-block. A variety of genes, pseudogenes, autologous DNA transposons and retrotransposons such as Alu and ERVK9 were used to categorize the ten duplicons into four distinct structural groups. The phylogenetic relationship of the ten duplicons was examined by using the neighbour joining method to analyze transposon sequence topologies of selected Alu members, LTR16B and Charlie9. On the basis of these structural groups and the phylogeny of the duplicated transposon sequences, a duplication model was reconstructed involving four multipartite tandem duplication steps to explain the organization and evolution of the ten duplicons within the alpha-block of the chimpanzee and human. The phylogenetic analysis and inferred duplication history suggests that the Patr/HLA-F was the first MHC class I gene to have been fixed and not required as a precursor for further duplication within the alpha-block of the ancestral species.

Animals↗
PubMed1981

The A.D.A. role delineation for the field of clinical dietetics: 2. Methodology and summary of results.

Drawing upon the experience of previous contractors with the Division of Associated Health Professions, A.D.A. project staff and consultants designed and implemented a study methodology suited to the unique characteristics of the profession. To delineate the "actual" entry role of clinical dietetics and develop an informational base for further research, project staff compiled qualitative data which were subsequently analyzed by the Working Committee, using structured group decision-making processes. Next, a survey was administered to dietetic and other health professionals to form a data base of opinion on the degree to which clinical dietetic personnel should be accountable for the performance of specific responsibilities. Using group decision-making processes, the "appropriate" entry role responsibilities and supporting skills and knowledge for clinical dietetics were delineated by filtering data through the professional judgment and expertise of the Working Committee. Practice levels were identified, and skill and knowledge statements were weighted for degree of importance, again using structured group decision-making techniques. Two practice levels of the entry role were delineated: clinical dietitian and clinical dietetic technician. Through a process involving the Advisory and the Working Committees, project documents were refined for implementation by the profession.

Clinical Competence↗
PubMed2004

Stability-based validation of clustering solutions.

Data clustering describes a set of frequently employed techniques in exploratory data analysis to extract "natural" group structure in data. Such groupings need to be validated to separate the signal in the data from spurious structure. In this context, finding an appropriate number of clusters is a particularly important model selection question. We introduce a measure of cluster stability to assess the validity of a cluster model. This stability measure quantifies the reproducibility of clustering solutions on a second sample, and it can be interpreted as a classification risk with regard to class labels produced by a clustering algorithm. The preferred number of clusters is determined by minimizing this classification risk as a function of the number of clusters. Convincing results are achieved on simulated as well as gene expression data sets. Comparisons to other methods demonstrate the competitive performance of our method and its suitability as a general validation tool for clustering solutions in real-world problems.

Algorithms↗
PubMed1992

Diversity and commonality in music performance: an analysis of timing microstructure in Schumann's "Träumerei".

This study attempts to characterize the temporal commonalities and differences among distinguished pianists' interpretations of a well-known piece, Robert Schumann's "Träumerei." Intertone onset intervals (IOIs) were measured in 28 recorded performances. These data were subjected to a variety of statistical analyses, including principal components analysis of longer stretches of music and curve fitting to series of IOIs within brief melodic gestures. Global timing patterns reflected the hierarchical grouping structure of the composition, with pronounced ritardandi at the ends of major sections and frequent expressive lengthening of accented tones within melodic gestures. Analysis of local timing patterns, particularly of within-gesture ritardandi, revealed that they often followed a parabolic timing function. The major variation in these patterns can be modeled by families of parabolas with a single degree of freedom. The grouping structure, which prescribes the location of major tempo changes, and the parabolic timing function, which represents a natural manner of executing such changes, seem to be the two major constraints under which pianists are operating. Within these constraints, there is room for much individual variation, and there are always exceptions to the rules. The striking individuality of two legendary pianists, Alfred Cortot and Vladimir Horowitz, is objectively demonstrated here, as is the relative eccentricity of several other artists.

Female↗
PubMed1995

Detection of internal cavities in globular proteins.

We have undertaken a study of internal cavities in five protein structure groups, each containing different crystallographic structure determinations of the same protein, to understand better the nature of packing defects in protein tertiary architectures. Our results show that cavity detection and consistency of detection are highly dependent on probe and cavity size, cavity position within the globular protein and the local "quality' (r.m.s. deviation) of structural consistency within the group. The consistency of solvent placement within cavities has also been examined. We provide guidelines for estimating the likelihood of a given cavity to be an actual packing defect or to be a result of experimental error.

Animals↗
PubMed1986

[Changes in the structure of group behavior in callosotomized rhesus monkeys].

The studies were performed on 4 intact and 3 callosotomized adult male rhesus monkeys that comprised one social group. Group behaviour of all the monkeys was investigated by the frequency method of social contacts registration. Both aggressive and friendly contacts were registered. The results obtained have shown a considerable decrease in social contacts of callosotomized rhesus monkeys, as compared to normal animals. The aggressive contacts prevailed in the behaviour of the operated monkeys. The data suggest that callosotomy does not only significantly decrease the frequency, but also alters the structure of social contacts in the rhesus monkeys.

Aggression↗
PubMed1978

Binding of aggregated human beta2-microglobulin to surface protein structure in group A, C, and G streptococci.

A novel mammalian-microbial "short circuit" has been demonstrated between aggregated human beta2-microglobulin and group A, C, and G streptococci. Bacteria belonging to nine gram-positive and three gram-negative species were tested for binding of radiolabeled beta2-microglobulin. All 10 individual strains of group A streptococci showed a high degree of reactivity with aggregated human beta2-microglobulin. Among 27 group C and 28 group G streptococci, 9 and 6 strains, respectively, were highly reactive, whereas the remaining strains showed a lower, but definite level of beta2-microglobulin binding. Of 11 group B streptococci, 4 were slightly positive. All strains among the other eight species were completely negative. Simultaneous testing of A, C, and G streptococci for immunoglobulin binding showed a lack of correlation between type II and III Fc reactivity and beta2-microglobulin binding. There was no inhibition of uptake of aggregated beta2-microglobulin to reactive strains when excess amounts of human immunoglobulin were added. The beta2-microglobulin-binding surface structure was found to be markedly sensitive to trypsin digestion. The relative trypsin resistance of the immunoglobulin-binding protein in the digestion experiments further demonstrated the dissociation between these two reactivities.

Bacterial Proteins↗
PubMed2005

A branching process, its application in biology: influence of demographic parameters on the social structure in mammal groups.

Branching processes are widely used in biology. This theoretical tool is used in cell dynamics, epidemics and population dynamics. In population dynamics, branching processes are mainly used to access extinction probabilities of populations, groups or families, with the Galton-Watson branching process. Many mammal species live in socially-structured groups, and the smallest units of these groups are lineages (or families) of kin-related individuals. In many primate species, these lineages are matrilines, as females remain in their natal groups most of the time, whereas males generally disperse. Lineage parameters, such as numbers of matrilines, size of each matriline and average degree of relatedness, could strongly influence the genetic composition of groups. Evidence indicates that division along matrilines could induce substantial differentiation among fission groups. Here, we develop a novel mathematical model based on the branching process theory describing demographic dynamics of groups. The main result of this model is an explicit analytical expression of the joint distribution of numbers of lineages and sizes of socially-structured groups. We investigated the influence of parameters such as natality and mortality on the outcome of the process, including extinction probability. Finally, we discuss this theoretical result with respect to biological significance.

Animals↗