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PubMed2005

The efficacy of a structured group therapy intervention in improving communication and coping skills for adult cochlear implant recipients.

This paper reports on an evaluation of a structured group therapy intervention for adult cochlear implant (CI) recipients designed to improve overall communication and coping skills. 33 adult CI recipients (14 males, 19 females; mean age 61; 1-14 years since Cl) participated in a 2-day structured group therapy intervention with a follow-up session 4 weeks later. Measures were: communication behaviors (CPHI), assertiveness (Rathus), depression (DASS), and behavior during conversation (Dyalog). TCI personality traits were utilized as predictors of change. Repeated measures analyses showed that participants demonstrated significant improvements on measures of assertiveness, emotional well-being, and coping behaviors at 3 months post-intervention that persisted at a 12-month follow-up. Several personality traits predicted change. Although subjects had presumably adapted to their cochlear implants and had learned communication strategies in hearing rehabilitation programs, the improvements on several measures suggest that a structured group therapy intervention can enhance outcome following cochlear implantation.

Adaptation, Psychological↗
PubMedDate not supplied

Group-structured genetic models in analyses of the population and behavioral ecology of poikilothermic vertebrates.

Estimates of gene correlations among individuals within and among populations are frequently derived from statistical analyses of genetic data (e.g., F statistics). These measures can be important tools in molecular ecology and conservation, and offer important insights into population breeding structure. Using recently derived theory developed for group-structured populations, we show that fixation indices, when combined with basic population ecological and demographic data can be used to investigate population mating systems and to predict dispersal rates, trajectories and asymptotic levels of fixation indices, and effective population size. Four case studies of poikilothermic vertebrates are used to demonstrate the broad utility of evolutionary and ecological inferences afforded by group-structured models.

Animals↗
PubMed2006

A systematic review of structured group interventions with mentally disordered offenders.

BACKGROUND: Over the last 15 years, rehabilitation of offenders has been rigorously researched, resulting in new knowledge and understanding about factors decreasing recidivism amongst them. Typically, such interventions have been based on cognitive behavioural therapy. However, until recently, little research had been carried out on the rehabilitation of offenders with mental disorder. The authors present the first systematic review of the efficacy of structured group interventions with mentally disordered offenders. AIM: To evaluate structured group interventions with mentally disordered offenders through systematic review of the evidence for their efficacy and effectiveness. METHODS: A standardized search strategy, with complementary methods of data retrieval to ensure a high degree of recall, was employed. Meta-analysis was not undertaken due to sample heterogeneity and lack of comparable data. Instead, effect sizes were calculated on all papers with sufficient data. Pooled effect sizes were calculated for groups of interventions with a similar focus. RESULTS: Twenty studies were retrieved that fitted the inclusion criteria. It was possible to categorize these, predominantly British, studies into four main themes: problem-solving; anger/aggression management; self-harm; and other. The mean pooled effect sizes for the first two groups were suggestive of a moderate to high effect, but methodological variation means that these findings should still be treated as preliminary. DISCUSSION AND CONCLUSIONS: Calculated effect sizes give optimism for the efficacy of structured group interventions with mentally disordered offenders. It is important now that more rigorous and consistent research methods be applied, even in secure hospital environments. Some suggestions towards achieving this are offered, drawing from the work to date, inclusive of the need for agreement on common outcome measures and development of networks to improve sample sizes.

Aggression↗
PubMed2005

Effects of information and group structure on evolution of altruism: analysis of two-score model by covariance and contextual analyses.

An altruistic individual has to gamble on cooperation to a stranger because it does not know whether the stranger is trustworthy before direct interaction. Nowak and Sigmund (Nature 393 (1998a) 573; J. Theor. Biol. 194 (1998b) 561) presented a new theoretical framework of indirect reciprocal altruism by image scoring game where all individuals are informed about a partner's behavior from its image score without direct interaction. Interestingly, in a simplified version of the image scoring game, the evolutionarily stability condition for altruism became a similar form of Hamilton's rule, i.e. inequality that the probability of getting correct information is more than the ratio of cost to benefit. Since the Hamilton's rule was derived by evolutionarily stable analysis, the evolutionary meaning of the probability of getting correct information has not been clearly examined in terms of kin and group selection. In this study, we applied covariance analysis to the two-score model for deriving the Hamilton's rule. We confirmed that the probability of getting correct information was proportional to the bias of altruistic interactions caused by using information about a partner's image score. The Hamilton's rule was dependent on the number of game bouts even though the information reduced the risk of cooperation to selfish one at the first encounter. In addition, we incorporated group structure to the two-score model to examine whether the probability of getting correct information affect selection for altruism by group selection. We calculated a Hamilton's rule of group selection by contextual analysis. Group selection is very effective when either the probability of getting correct information or that of future interaction, or both are low. The two Hamilton's rules derived by covariance and contextual analyses demonstrated the effects of information and group structure on the evolution of altruism. We inferred that information about a partner's behavior and group structure can produce flexible pathways for the evolution of altruism.

Altruism↗
PubMed2000

New ways of determining structural groups in brown coals and their bioconversion products by FT IR spectroscopy.

New methods of determining the structural groups -COOH and -CH2- have been developed. The investigation of carboxyl groups is possible both after derivatization with p-fluorophenacylbromide and by quantitative interpretation of the Fourier transform infrared (FT IR) spectra. There exists a linear relationship between the results of these two methods that is generally valid for the analysis of all brown coal components. The maximum extinction coefficient of the symmetric stretching vibration band of the CH2 groups has been determined using model substances. This allows quantification of this structural group directly from the FT IR spectrum. The results agree with the contents of methylene groups as determined by 13C-cross polarization-magic angle spinning nuclear magnetic resonance (13C CPMAS NMR) spectroscopy. Using these methods, the COOH and CH2 groups contained in brown coals of the North Rhine region and in their bioconversion products have been quantified.

Biodegradation, Environmental↗
PubMed2005

Democracy justifies the means: political group structure moderates the perceived legitimacy of intergroup aggression.

The present research tested the hypothesis that the political structure of conflicting groups moderates perceived legitimacy of intergroup aggression. In two experiments, participants read scenarios of fictitious summer camps in which members of one group aggressed members of another group. The political structure of both the perpetrator and the victim groups was described as either egalitarian (defined with democratic decision-making procedures) or hierarchical (authoritarian decision-making procedures). Results of both experiments showed that aggressions perpetrated by members of egalitarian groups at the expense of members of hierarchical groups were evaluated as less illegitimate than aggressions committed in the three remaining conditions. This effect is discussed as a function of the higher social value attributed to democratic groups.

Adolescent↗
PubMed2005

Growing network model for community with group structure.

We propose a growing network model for a community with a group structure. The community consists of individual members and groups, gatherings of members. The community grows as a new member is introduced by an existing member at each time step. The new member then creates a new group or joins one of the groups of the introducer. We investigate the emerging community structure analytically and numerically. The group size distribution shows a power-law distribution for a variety of growth rules, while the activity distribution follows an exponential or a power law depending on the details of the growth rule. We also present an analysis of empirical data from online communities the "Groups" in http://www.yahoo.com and the "Cafe" in http://www.daum.net, which show a power-law distribution for a wide range of group sizes.

Journal Article↗
PubMed1989

Structured group intervention model for AIDS patients.

We have gathered and analyzed data on 50 gay men with AIDS before and after a ten-week structured group intervention aimed at reducing psychological distress and improving coping skills. Among the major findings have been information relating coping strategies to depression and anxiety, information about the support networks of people with AIDS, and the relationships between coping strategies, support networks and psychological mood states. We have also found that structured group interventions comprised of problem solving techniques, health education, relaxation training and emotional support are helpful in reducing anxiety and depression and in teaching people more positive ways of coping with their illness.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Role of head group structure in the phase behavior of amino phospholipids. 1. Hydrated and dehydrated lamellar phases of saturated phosphatidylethanolamine analogues.

Analogues of dimyristoylphosphatidylethanolamine (DMPE) have been prepared with head groups modified by N-alkylation, alkylation of carbon 2 of the ethanolamine group, or interposition of extra methylene segments between the phosphoryl and amino groups. The phases formed by these lipids in aqueous dispersions have been examined by high-sensitivity differential scanning calorimetry and Raman spectroscopy. All of the DMPE analogues examined, excepting N-methyl-DMPE but including N-ethyl-DMPE, form hydrated gel phases that are metastable with respect to a dehydrated "high-melting" solid phase that has been observed previously for DMPE itself. The properties and the conditions of formation of this high-melting phase are qualitatively distinct from those of the "subgel" phase, which is observed for dipalmitoylphosphatidylcholine and for some of the DMPE analogues examined in this study. The high-melting phases of different DMPE analogues all exhibit similarly tight packing of the acyl chains, which however do not pack according to a single type of subcell that can be universally and specifically associated with this phase. Increasing the size of the PE head group invariably decreases the melting temperature of the hydrated gel phase, even when the normal hydrogen-bonding capability of the head group is preserved. By contrast, addition of larger alkyl substituents to either the amino group or carbon 2 of the ethanolamine moiety substantially increases the transition temperature of the high-melting solid phase, indicating that the contributions of the head group to the energies of the hydrated gel and the high-melting phases are fundamentally different. Our results suggest that the head group structural requirements for a neutral phospholipid to form stable hydrated bilayers are rather stringent, a fact that may explain the overwhelming predominance of only a few such head group structures in most natural membranes.

Calorimetry, Differential Scanning↗
PubMed2025

Meta-analysis models with group structure for pleiotropy detection at gene and variant level using summary statistics from multiple datasets.

Genome-wide association studies (GWASs) have highlighted the importance of pleiotropy in human diseases, where one gene can impact 2 or more unrelated traits. Examining shared genetic risk factors across multiple diseases can enhance our understanding of these conditions by pinpointing new genes and biological pathways involved. Furthermore, with an increasing wealth of GWAS summary statistics available to the scientific community, leveraging these findings across multiple phenotypes could unveil novel pleiotropic associations. Existing selection methods examine pleiotropic associations one by one at a scale of either the genetic variant or the gene, and thus cannot consider all the genetic information at the same time. To address this limitation, we propose a new approach called MPSG (Meta-analysis model adapted for Pleiotropy Selection with Group structure). This method performs a penalized multivariate meta-analysis method adapted for pleiotropy and takes into account the group structure information nested in the data to select relevant variants and genes (or pathways) from all the genetic information. To do so, we implemented an alternating direction method of multipliers algorithm. We compared the performance of the method with other benchmark meta-analysis approaches such as GCPBayes, PLACO, and ASSET by considering as inputs different kinds of summary statistics. We provide an application of our method to the identification of potential pleiotropic genes between breast and thyroid cancers.

Humans↗
PubMed2006

Restricted mating dispersal and strong breeding group structure in a mid-sized marsupial mammal (Petrogale penicillata).

Ecological genetic studies have demonstrated that spatial patterns of mating dispersal, the dispersal of gametes through mating behaviour, can facilitate inbreeding avoidance and strongly influence the structure of populations, particularly in highly philopatric species. Elements of breeding group dynamics, such as strong structuring and sex-biased dispersal among groups, can also minimize inbreeding and positively influence levels of genetic diversity within populations. Rock-wallabies are highly philopatric mid-sized mammals whose strong dependence on rocky terrain has resulted in series of discreet, small colonies in the landscape. Populations show no signs of inbreeding and maintain high levels of genetic diversity despite strong patterns of limited gene flow within and among colonies. We used this species to investigate the importance of mating dispersal and breeding group structure to inbreeding avoidance within a 'small' population. We examined the spatial patterns of mating dispersal, the extent of kinship within breeding groups, and the degree of relatedness among brush-tailed rock-wallaby breeding pairs within a colony in southeast Queensland. Parentage data revealed remarkably restricted mating dispersal and strong breeding group structuring for a mid-sized mammal. Breeding groups showed significant levels of female kinship with evidence of male dispersal among groups. We found no evidence for inbreeding avoidance through mate choice; however, anecdotal data suggest the importance of life history traits to inbreeding avoidance between first-degree relatives. We suggest that the restricted pattern of mating dispersal and strong breeding group structuring facilitates inbreeding avoidance within colonies. These results provide insight into the population structure and maintenance of genetic diversity within colonies of the threatened brush-tailed rock-wallaby.

Animals↗
PubMed1980

Structured group treatment of couples experiencing sexual dysfunctions.

This paper describes a structured, time-limited method for treating couples in which both people are experiencing sexual dysfunctions. In our previous research, we found that group treatment was as effective as single-couple treatment for treating men experiencing premature ejaculation and women experiencing secondary orgasmic dysfunction. In this article we have described our procedures for evaluating and selecting group participants, our 12-week structured group treatment format, the group process, common problems and resistances, and our methods for assessing treatment outcome. Our structured group treatment approach is a cost efficient and effective method for treating the many couples experiencing sexual dysfunctions.

Female↗
PubMed1993

Peer group structure and adolescent cigarette smoking: a social network analysis.

Social network theory and analysis are applied to examine whether adolescents who fill various social positions that characterize peer group structure differ in prevalence of current smoking. One thousand and ninety-two (1,092) ninth graders in one school system named their three best friends, allowing the identification of each adolescent as clique member, clique liaison, or isolate. At four of five schools, the odds of being a current smoker were significantly higher for isolates than for clique members and liaisons. The relationship was not explained by demographic variables or by the number of friends who smoke.

Adolescent↗
PubMed1997

Absence due to illness among toddlers in day-care centres in relation to child group structure.

The present work demonstrates a close association between illness-associated absence among children below 4 y of age in day-care, and the age-related composition of the child groups. The study, which spanned a 4 y period and is based on illness-related absence from day-care in a Stockholm suburb, shows that morbidity decreases significantly among young children as age-integration in the groups is intensified. Absence due to illness was most common in toddler groups of infants up to 3 y of age. Among sibling groups of children in the age range 0-6 y, illness-related absence was lower among toddlers compared to toddlers in age-separated groups, and significantly lower in extended sibling groups in the age range 0-12 y. Morbidity among children older than 3 y was not affected in the same way by group structure.

Absenteeism↗
PubMed1987

The dependence of glyceroglycolipid orientation and dynamics on head-group structure.

The head-group orientations and molecular dynamics of three glyceroglycolipids in aqueous dispersions, as determined by 2H-NMR, are compared. 1,2-Di-O-tetradecyl-3-O-(alpha-D-glucopyranosyl)-sn-glycerol (alpha-DTGL) and 1,2-di-O-tetradecyl-3-O-(alpha-D-mannopyranosyl)-sn-glycerol (alpha-DTML), selectively 2H-labelled on the pyranose ring, at the exocyclic hydroxymethyl group, and at C3 of glycerol, have been studied by 2H-NMR and the results compared with those reported earlier for 1,2-di-O-tetradecyl-3-O-(beta-D-glucopyranosyl)-sn-glycerol (beta-DTGL). The alpha-glucolipid exhibits a gel-to-liquid crystal phase transition and a lamellar to hexagonal mesophase transition at temperatures which are similar to those of the beta-anomer, beta-DTGL. However, alpha-DTGL exhibits head group orientations and molecular ordering in the lamellar and hexagonal phases which differ strikingly with those reported for the corresponding beta-glucolipid. Whereas the head group of beta-DTGL is extended away from the bilayer surface into the aqueous phase, that of alpha-DTGL is almost parallel to the bilayer surface. alpha-DTGL exhibits a molecular order parameter of 0.56 which is substantially greater than that of its anomer, beta-DTGL, 0.45. The latter indicates that the head group region of the alpha-glyceroglucolipid is characterized by smaller angular fluctuations than that of beta-DTGL. On entering the hexagonal mesophase the pyranose ring of the beta-glucolipid undergoes a large reorientation relative to the motional axis of the head group, whereas the alpha-anomer exhibits only a small orientational change. 1,2-Di-O-tetradecyl-3-O-(alpha-D-mannopyranosyl)-sn-glycerol (alpha-DTML) undergoes a phase transition at 47 degrees C, attributed to the unusual lamellar gel to hexagonal phase transition. The pyranose ring of alpha-DTML, in a mixture with dimyristoylphosphatidylcholine (1:9 mol ratio) to give a lamellar liquid crystalline phase, is oriented away from the bilayer surface into the aqueous environment and has an Smol of 0.75. The results for alpha-DTML, 2H-labelled at the C3 position of glycerol, suggest that this segment also has high molecular ordering. alpha-DTML in a lamellar environment has the least flexible membrane surface of the glyceroglycolipids investigated to date. 2H-NMR spin lattice relaxation times have been used to probe the head group motions of the glycolipids. The results indicate that the rate of head group motion increases in the order alpha-DTML less than alpha-DTGL less than beta-DTGL.(ABSTRACT TRUNCATED AT 400 WORDS)

Chemical Phenomena↗
PubMed1997

Group structure and its development in an isolated and confined environment.

An Antarctic winter-over has been regarded as one of the analogue situations in long-term space flight, especially from the aspect of prolonged isolation and a confined environment. Thus, Antarctic winter-overs at research stations offer us a unique opportunity to observe the dynamics of group and individual behavior. This research examines group structure and its development during long-term isolation and confinement in an Antarctic research station using direct, quantitative observations.

Adaptation, Psychological↗