Reinforcement theory of pesonality and social system: dominance and position in a group power structure.
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Affect↗
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From subgenome analysis to protein structure.
Groups of related genes abound in large eukaryotic genomes. In such 'subgenomes', homology modeling carried out for a few genes will probably have relevance to the entire group. Subgenomes also afford unique ways of determining protein structural information. In addition to analyses based on the quantification of residue variability in paralogs, two-way comparisons, both within and among species, help to disclose functional amino acids. Comparative studies of gene families throughout the mammalian genome will also help elucidate the functional significance of single nucleotide polymorphisms in coding regions.
Animals↗
Effects of project versus parallel groups on social interaction and affective responses in senior citizens.
Using activity analysis, occupational therapists structure group activities to meet the needs and goals of group members. This study compared the effects of project group structure (subjects participate together on a common task) with parallel group structure (subjects each have a task) in a sample of healthy seniors (32 women and 9 men). Subjects randomly assigned to either experimental condition made creative and imitative collages in a counter-balanced order. Time-sampled observations revealed that project group subjects talked and looked at others significantly more than parallel group subjects. On-task and laughing behaviors were also measured, but results were inconclusive. Project group subjects rated their activities higher on the action factor of the Osgood semantic differential (OSD) than did parallel group subjects, but there were no other differences on the OSD or on MacKenzie's Group Climate Questionnaire. Nor were there significant main effects between the creative collage and the imitative collage. Results are discussed both in terms of group task structure as an occupational therapy tool and in terms of methodologies for future activity analysis research.
Affect↗
[High mobility group proteins: structure, localization, function].
High motility group proteins (HMG) are extracted by 5% HCIO4 and 0.35 M NaCl and are characterized by low molecular mass and a high content of acidic and basic amino acids. There is evidence that HMG are involved in the formation of transcriptionally active chromatin.
Amino Acids↗
Effects of concentration, head group, and structure of surfactants on the degradation of phenanthrene.
The effects of concentration, polar/ionic head group, and structure of surfactants on the biodegradation of polycyclic aromatic hydrocarbons (PAHs) in the aqueous phase, as well as their effects on the bacterial activity were investigated. The toxicity ranking of studied surfactants is: non-ionic surfactants (Tween 80, Brij30, 10LE and Brij35)<anionic surfactants (LAS)<cationic surfactants (TDTMA). For the same head group and similar molecular structure, the toxicity to the bacteria is due to the chain length, in which the toxicity becomes lower as the chain length increases. The bacterial growth increased slightly when phenanthrene and LAS (<or=10 mgL(-1)) served the sole carbon and energy resource. However, the degradation of (14)C-phenanthrene showed either a decrease or no obvious change with the surfactants present at all tested concentrations (5-40 mgL(-1)). Thus, the surfactant addition is not beneficial to the removal of phenanthrene or other PAH contaminants due presumably to the preferential utilization of surfactants at low levels as the non-toxic nutrient resource and to the high toxicity of the surfactants at high levels to the microorganism activity. Biodegradation of phenanthrene was also influenced by the surfactant concentration, head group type, and structure. Much more research has yet to be completed on the use of surfactants for soil remediation due to the surfactant toxicity or biodegradation effect.
Biodegradation, Environmental↗
Mixing behavior of binary insoluble phospholipid monolayers. Analysis of the mixing properties of binary lecithin and cephalin systems by application of several surface and spreading techniques.
The detailed miscibility analysis of binary phospholipid monolayers requires the application of a variety of spreading and surface techniques which often yield complementary results. Testing the equilibrium state of the binary monolayer by long-time experiments is also of great importance. Studies of the compression and spreading behavior of binary monomolecular systems form a basis for the determination of binary monomolecular phase diagrams. Within these plots different phase regions occur which permit clear statements regarding the miscibility state. Additional knowledge of the miscibility properties (phase diagrams) of the binary bulk systems is required. From the analogy of the properties of the bulk systems, the miscibility state of the monolayers is also determined by the temperature, and we can classify the monolayers of binary lecithin and cephalin systems into systems of complete miscibility, partial miscibility and complete immiscibility. In addition to the differences in the chemical structure of the mixing components, the film states in the monolayer and the miscibility behavior of the bulk systems are also influencing factors. If one of the components does not produce a spreading pressure, miscibility gaps occur in the phase diagram of the phospholipid monolayer. The miscibility gap, expressed by a constant spreading pressure, indicates complete immiscibility within this concentration range. If both components produce spreading pressures, and condensed and liquid-expanded film states within the considered temperature range, partial miscibility of the components becomes probable. The most effective parameter is then the difference in the chemical structure of the components. When both components produce spreading pressures and condensed films, the chemical structure of the mixing phospholipid compounds within their hydrophilic and hydrophobic parts is of essential importance. Depending on the differences in the chemical structures of their chains and their head groups in the case of binary phospholipid monolayers, the following possibilities result: complete miscibility, partial miscibility and complete immiscibility of the lecithins and the cephalins. Complete miscibility within the binary phospholipid monolayer takes place in the case of identical head-group structure and where there are only small differences in the chain length of the fatty acid groups. With increasing hydrocarbon chain length differences, partial miscibility or even complete immiscibility can occur within the monolayer. Chemical differences in the head-group structure of the mixing components have a similar influence. In the case of binary lecithin/cephalin mixtures, the differences in the head-group structure affect the miscibility behavior more than the chain length differences do in the case of lecithin/lecithin and cephalin/cephalin mixtures.(ABSTRACT TRUNCATED AT 400 WORDS)
Liposomes↗
Detection of N-acetylgalactosaminyltransferase mRNA which determines expression of Sda blood group carbohydrate structure in human gastrointestinal mucosa and cancer.
The Sda blood group carbohydrate structure, GalNAcbeta1-4[NeuAcalpha2-3]Galbeta1-4GlcNAc-R, is expressed on glycolipid and glycoprotein in human gastrointestinal mucosa. The expression of the Sda determinant dramatically decreases in cancer tissue. The activity of the beta1,4N-acetylgalactosaminyltransferase (Sda-GalNAcT), which transfers GalNAc to NeuAcalpha2-3Galbeta1-4Glc(NAc)-R, correlates with the expression of the Sda immuno-epitope. From the total RNA fraction of human gastric mucosa, we have amplified a cDNA segment by reverse-transcription-polymerase-chain reaction (RT-PCR), using primers designed according to the cDNA sequence of a murine beta1,4GalNAcT which synthesizes the Sda determinant. An RT-PCR product of 390 bp shared 85% nucleotide identity with the murine Sda-related beta1,4GalNAcT. This RT-PCR product hybridized to a transcript in mRNA prepared from human gastric mucosa. In RT-PCR using specific primers to this PCR product, Sda-GalNAcT mRNA was detected in all samples of normal stomach and small intestine examined and the majority of normal colonic specimens. Six out of nine cases of gastric cancer, and 9 out of 13 cases of colonic cancer failed to produce the target DNA. These results correlate with the beta1,4GalNAcT activity measured in the same samples. In conclusion, a segment of the cDNA for betal,4GalNAcT which determines expression of the Sda carbohydrate structure was obtained, and reduced transcription of this beta 1,4GalNAcT resulted in the disappearance of the Sda epitope in gastrointestinal cancer.
Animals↗
Defining functional groups, core structural features and inter-domain tertiary contacts essential for group II intron self-splicing: a NAIM analysis.
Group II introns are self-splicing RNA molecules that are of considerable interest as ribozymes, mobile genetic elements and examples of folded RNA. Although these introns are among the most common ribozymes, little is known about the chemical and structural determinants for their reactivity. By using nucleotide analog interference mapping (NAIM), it has been possible to identify the nucleotide functional groups (Rp phosphoryls, 2'-hydroxyls, guanosine exocyclic amines, adenosine N7 and N6) that are most important for composing the catalytic core of the intron. The majority of interference effects occur in clusters located within the two catalytically essential Domains 1 and 5 (D1 and D5). Collectively, the NAIM results indicate that key tetraloop-receptor interactions display a specific chemical signature, that the epsilon-epsilon' interaction includes an elaborate array of additional features and that one of the most important core structures is an uncharacterized three-way junction in D1. By combining NAIM with site-directed mutagenesis, a new tertiary interaction, kappa-kappa', was identified between this region and the most catalytically important section of D5, adjacent to the AGC triad in stem 1. Together with the known zeta-zeta' interaction, kappa-kappa' anchors D5 firmly into the D1 scaffold, thereby presenting chemically essential D5 functionalities for participation in catalysis.
Base Sequence↗
Cloning of four cyclins from maize indicates that higher plants have three structurally distinct groups of mitotic cyclins.
While a large number of cyclins have been described in animals and yeasts, very limited information is available regarding cyclins in plants. We describe here the isolation of cDNA clones encoding four putative mitotic cyclins from maize. All four cyclins were able to induce maturation of Xenopus oocytes, demonstrating that they can act as mitotic cyclins in this system. Northern analysis showed that all four cyclins were expressed only in actively dividing tissues and organs, with a stronger correlation between expression and mitotic activity than is observed with cdc2. The deduced protein sequences suggest that the four maize cyclins belong to the cyclin A and B families identified from animal and yeast studies but that they cannot be described easily as either A-type or B-type cyclins. However, comparison with previously cloned plant cyclins shows that cyclins in higher plants form three distinct structural groups that have been conserved in both monocotyledonous and dicotyledonous species and that cyclins from all three groups are present within a single plant species.
Amino Acid Sequence↗
Violent coalitionary attack by female mandrills against an injured alpha male.
Female contact aggression against males is relatively rare in species in which the adult males are larger than the females, but it has the potential to influence group structure, male group membership, tenure, and dominance rank. We report an incident in which female mandrills living in a semi-free-ranging group in Franceville, Gabon, attacked a male that was apparently incapacitated after a fight with another male and was unable to escape. The attack involved the alpha male and did not occur in a sexual or infanticidal context. Other adult and adolescent males observed the attack, but when one adult male attempted to participate he was chased away by the females. This observation adds to reports of female coalitions excluding unwanted males from primate groups, or even killing them. The fact that this can also occur in mandrills suggests that females have a degree of control over male group membership, despite the large degree of sexual dimorphism in this species, and highlights the importance of coalitions in primate social organization.
Aggression↗
Immunochemical studies on blood groups. XXXIV. Structures of some oligosaccharides produced by alkaline degradation of blood group A, B, and H substances.
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ABO Blood-Group System↗
Endorsement of formal leaders: an integrative model.
This experiment develops an integrative, path-analytic model for the endorsement accorded formal leaders. The model contains four independent variables reflecting aspects of group structure (i.e., group success-failure, the payoff distribution, the degree of support by others members for the leader, and the vulnerability of the leader). Also included are two intervening variables reflecting perceptual processes (attributed competence and attributed fairness), and one dependent variable endorsement). The results indicate that endorsement is greater when the group's success is high, when the payoff distribution is flat rather than hierarchial, and when the leader is not vulnerable to removal from office. Other support had no significant impact on endorsement. Analyses further demonstrate that the effect of success-failure on endorsement is mediated by attributed competence, while the effect of the payoff distributed is mediated by attributed fairness. These results suggest that moral and task evaluations are distinct bases of endorsement.
Achievement↗
Determining sociability, social space, and social presence in (a)synchronous collaborative groups.
The effectiveness of group learning in asynchronous distributed learning groups depends on the social interaction that takes place. This social interaction affects both cognitive and socioemotional processes that take place during learning, group forming, establishment of group structures, and group dynamics. Though now known to be important, this aspect is often ignored, denied or forgotten by educators and researchers who tend to concentrate on cognitive processes and on-task contexts. This "one-sided" educational focus largely determines the set of requirements in the design of computer-supported collaborative learning (CSCL) environments resulting in functional CSCL environments. In contrast, our research is aimed at the design and implementation of sociable CSCL environments which may increase the likelihood that a sound social space will emerge. We use a theoretical framework that is based upon an ecological approach to social interaction, centering on the concept of social affordances, the concept of the sociability of CSCL environments, and social presence theory. The hypothesis is that the higher the sociability, the more likely that social interaction will take place or will increase, and the more likely that this will result in an emerging sound social space. In the present research, the variables of interest are sociability, social space, and social presence. This study deals with the construction and validation of three instruments to determine sociability, social space, and social presence in (a)synchronous collaborating groups. The findings suggest that the instruments have potential to be useful as measures for the respective variables. However, it must be realized that these measures are "first steps."
Adult↗
Neuropeptide function: the invertebrate contribution.
The following is a list of generalizations that arise from considering the present state of knowledge concerning the functions of invertebrate peptides. Some of these clearly also apply to vertebrates. Invertebrate peptides can be classified into structurally related groups. Structural similarity of peptides may represent true evolutionary homology by selection acting on an original gene. Alternatively, independent evolution of similar genes may have occurred because certain amino acid sequences represent optimal solutions to complex functional problems. Invertebrate neuropeptides have multiple functions. Thus, proctolin is a cardioactive peptide, a skeletal neuromuscular transmitter, a hindgut neuropeptide, a peptide of CNS interneurons (Keshishian & O'Shea 1984) and may have humoral roles. Invertebrate peptides act through a variety of molecular mechanisms. Generalizations about the mechanism cannot yet be made. Thus, proctolin's action on crustacean skeletal muscle is not associated with stimulation of cyclic-AMP or protein phosphorylation, but the action of SCPB on molluscan skeletal muscle involves elevation of cAMP. Invertebrate peptide inactivation can be caused by proteolysis that can also function to enhance peptide bioactivity. Proctolin is made virtually biologically inactive by any proteolysis, but alpha-BCP bioactivity is enhanced by two steps of carboxy peptidase digestion before being functionally inactivated. Protease action on released peptides is not necessarily a "simple" form of transmitter inactivation. Protease action also involves functional processing whereby the temporal and spatial parameters of a peptide's action may be shaped. Invertebrate neuropeptides are frequently co-localized with other neuroeffectors. Peptides may be co-localized and released with other active peptides as in the bag-cell example, or may be coactive with more conventional transmitters, as in the Ds motoneuron example. In such circumstances there is no reason to view either transmitter as primary or secondary. Invertebrate neuropeptides are widely involved in the control of muscle contraction. These effects may be locally and directly mediated as in the Ds motoneuron example or may be humoral. The peptide may act directly on the muscle contractile system or function to modulate the muscles' response to other motor input. Muscle contraction may be induced by a neuropeptide without depolarization of the muscle cells, for example see proctolin. Invertebrate neuropeptides are frequently involved in the control of oscillatory functions. In several examples peptides activate rhythmic myogenic contractions of cardiac and skeletal muscle.(ABSTRACT TRUNCATED AT 400 WORDS)
Amino Acid Sequence↗
Socialization groups: using The Book of Questions as a catalyst for interaction.
This article describes the use of The Book of Questions (Stock, 1987) as a tool for assessment and as a catalyst for social interaction in an acute short-term inpatient psychiatric unit. Examples of questions and how they can be used to provide information for the evaluation of personality style and social and interpersonal skills are provided. Group objectives, membership criteria and format, and leadership techniques are discussed. Analysis of the group activity and patients' responses to the group indicates that a group structured around The Book of Questions facilitates social interaction and is easily transferable to social activities outside of the structured therapeutic group setting and hospital environment.
Communication↗
Use of a group objective structured clinical examination with first-year medical students.
PURPOSE: To evaluate the implementation of a quarterly group objective structured clinical examination (GOSCE) to assess the patient-evaluation abilities of a medical school class. METHOD: The study subjects were 94 first-year students participating in the Principles of Clinical Medicine course at the Oregon Health Sciences University School of Medicine in 1992-93. To create the GOSCE, the authors modified the format of the quarterly objective structured clinical examination by making each standardized-patient station the site of an interaction between a standardized patient and a group of four or five students. The GOSCE's reliability, content and face validity, and expense were evaluated. Student feedback was obtained using a structured questionnaire. RESULTS: Performances varied both among the five stations of the GOSCE and among the 23 student groups: the mean percentage of items performed correctly per station was 83%, with a range of 73-97%. The reliability of the GOSCE's stations was low, with intraclass correlations during the three consecutive quarters of .29, .05, and .12. Despite no prior experience with this type of testing, the students' mean rating of the GOSCE's appropriateness was 3.8 (on a Likert scale of 1, poor, to 5, excellent), compared with 2.5 for the appropriateness of the written examination also used for quarterly assessment. The expense of the GOSCE was much less than the costs reported for the OSCE format. CONCLUSION: The use of the quarterly GOSCE favorably influenced the students, faculty, and curriculum. The GOSCE format made possible the assessment of a large number of students' abilities, without the time and expense needed to evaluate students individually.
Attitude↗
[New pathways in the treatment of psychologically drug dependent adolescents].
Based on a one-and-half year experience in a small group setting with drug dependent adolescents the change of group structure, the functioning of the group for its members, the leader's position within the group and the therapeutic relationship are analysed. In its beginning the group develops what can be called a "symbiotic group structure". Its transformation into that of a "working group" is the main task of therapy. The underlying processes can be compared with those of the beginning individuation in early childhood. Ego development begins, as M. Mahler and other modern investigators have shown, with the perception of one's own body and its representation in early ego formation. Using self awareness techniques, as we have done, is in this context a theoretical as well as practical well founded approach to the problems of psychic dependence.
Adolescent↗
Group performance as a function of task difficulty and size and structure of group. II.
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Adolescent↗