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Co-firing of biomass with coal combines the environmental benefits of renewable biomass with the high energy content of coal. Although the common numerical simulation treats the biomass and coal particles with ideal morphology, real particles often demonstrate nonsmoothed surface and irregular shape. To understand the impact of particle morphology in a group of biomass and coal particles co-firing together and to inform simple models appropriate, this study investigated the interparticle effects among particles using realistic particle morphology, focusing on fluid dynamics such as temperature distribution, flow patterns and drag coefficients. Particle-scale computational fluid dynamics (CFD) simulations using micro-CT imaging showed that realistic particle shapes resulted in nonuniform flow fields and temperature distributions with different reaction intensities due to the species transportation. It is in contrast to traditional ideal shape models, which often rely on simplified spherical representations of particles and cannot capture the intricacies of real particle shapes. Realistic models revealed more complex surfaces, highly irregular particle structures, and varied reaction zones that affected the overall dynamics. In addition, changing the orientation of one particle affects the combustion characteristics of neighboring particles. This effect is also not captured while using the spherical structure. These differences underscore the critical impact of particle morphology on drag and heat transfer, thereby challenging conventional spherical models. The findings of this study advocate for a paradigm shift in CFD modeling approaches, emphasizing the importance of realistic particle representation to improve the accuracy of predictions and enhance the co-firing system efficiency.

Group identity is important in moral judgments and decisions. People generally favor others who belong to their own group and are more reluctant to report their group members' wrongdoings to authorities. The current research extends this idea to examine the impact of intergroup relationship on moral judgments in the context of human-robot interaction (HRI). Our results showed that although neither group identity (ingroup or outgroup) nor agent type (human or robot) of the wrongdoers influenced the likelihood to report the wrongdoings, attitudes towards the wrongdoer depended on their group identity. The wrongdoers were evaluated more negatively when they were an ingroup instead of an outgroup member, be it human or robot. Moreover, human wrongdoers were ascribed lesser mental capacities than other humans. The current work highlights the interplay of intergroup dynamics and HRI in the moral domain, providing practical implications for building more cooperative human-robot teams. [ABSTRACT FROM AUTHOR]

Social facilitation is a phenomenon in which individuals from a group show behavioral changes due to the presence of other organisms of the same species. This happens through group interaction between these individuals, later increasing in frequency or intensity. Social facilitation studies began with humans but later extended to other species, including insects. The concepts of social facilitation in insects developed over the last 30 years are reviewed here. To that end, bibliographic searches were carried out to determine when the term social facilitation first emerged, how it was described in the research, where and when it was applied, and how the concept is currently employed. There has been, however, a steady decrease in the number of published texts conceptualizing the term social facilitation during the last three decades. Nevertheless, the terms emergent behavior, collective behavior, and information exchange enabled expansion of the survey on social facilitation, indicating that study in the area remains broad. The orders Blattodea (cockroaches and termites) and Hymenoptera (ants, wasps, and bees) were the most represented among the surveyed publications, indicating the occurrence of social facilitation due to eusociality. Eusocial organisms demonstrate unique social interactions, which makes them likely objects of future social facilitation studies.

Component‐based mechanical models compliant with Eurocode 3 becomes a popular alternative to complex Finite Element (FE) analyses for characterising the behaviour of steel joints. However, several key aspects are not accommodated by the existing spring models, i.e., group mechanisms, component interactions, and the variation of the shear force on the height of the column web panel. This paper introduces an innovative mechanical model suitable for the characterisation of structural joints under generalised loading. The model relies on the principles of the Component Method and incorporates the features systematically disregarded in the classical spring models. This guarantees code‐compliant predictions, and by virtue of its universality, the model can be used for any loading protocol (bending moment ‐ sagging or hogging, axial force, bending moment + axial force). Conclusive evidence given by comparisons with experimental data and analytical results shows the compliance of the proposed model with the Eurocode 3 and proves its accuracy in predicting the actual behaviour of steel joints. The proposed modelling methodology allows integrating the model as a macro‐element in dedicated software, thus presenting promising perspectives for reliable and time efficient structural analyses. [ABSTRACT FROM AUTHOR]

Traditionally, the main focus of the least squares regression is to study the effects of individual predictor variables, but strongly correlated variables generate multicollinearity which makes it difficult to study their effects. To resolve the multicollinearity issue without abandoning the least squares regression, for situations where predictor variables are in groups with strong within-group correlations but weak between-group correlations, we propose to study the effects of the groups with a group approach to the least squares regression. Using an all positive correlations arrangement of the strongly correlated variables, we first characterize group effects that are meaningful and can be accurately estimated. We then discuss the group approach to the least squares regression through a simulation study and demonstrate that it is an effective method for handling multicollinearity. We also address a common misconception about prediction accuracy of the least squares estimated model. [ABSTRACT FROM AUTHOR]

Many researchers have documented how AI and data driven technologies have the potential to have profound effects on our lives—in ways that make these technologies stand out from those that went before. Around the world, we are seeing a significant growth in interest and investment in AI in healthcare. This has been coupled with rising concerns about the ethical implications of these technologies and an array of ethical guidelines for the use of AI and data in healthcare has arisen. Nevertheless, the question of if and how AI and data technologies can be ethical remains open to debate. This paper aims to contribute to this debate by considering the wide range of implications that have been attributed to these technologies and asking whether current ethical guidelines take these factors into account. In particular, the paper argues that while current ethics guidelines for AI in healthcare effectively account for the four key issues identified in the ethics literature (transparency; fairness; responsibility and privacy), they have largely neglected wider issues relating to the way in which these technologies shape institutional and social arrangements. This, I argue, has given current ethics guidelines a strong focus on evaluating the impact of these technologies on the individual, while not accounting for the powerful social shaping effects of these technologies. To address this, the paper proposes a Multiscale Ethics Framework, which aims to help technology developers and ethical evaluations to consider the wider implications of these technologies. [ABSTRACT FROM AUTHOR]

The dominant approach in investigating the individual reliability for event-related potentials (ERPs) is to extract peak-related features at electrodes showing the strongest group effects. Such a peak-based approach implicitly assumes ERP components showing a stronger group effect are also more reliable, but this assumption has not been substantially validated and few studies have investigated the reliability of ERPs beyond peaks. In this study, we performed a rigorous evaluation of the test-retest reliability of ERPs collected in a multisensory and cognitive experiment from 82 healthy adolescents, each having two sessions. By comparing group effects and individual reliability, we found that a stronger group-level response in ERPs did not guarantee higher reliability. A perspective of neural oscillation should be adopted for the analysis of reliability. Further, by simulating ERPs with an oscillation-based computational model, we found that the consistency between group-level ERP responses and individual reliability was modulated by inter-subject latency jitter and inter-trial variability. The current findings suggest that the conventional peak-based approach may underestimate the individual reliability in ERPs and a neural oscillation perspective on ERP reliability should be considered. Hence, a comprehensive evaluation of the reliability of ERP measurements should be considered in individual-level neurophysiological trait evaluation and psychiatric disorder diagnosis.

Pile foundations supporting tall structures, such as wind turbines, chimneys, silos, elevated water tanks or bridge piers, are subjected during their life span to remarkably eccentric loads. These may lead to significant rotations which, however, cannot exceed the limiting values corresponding to the safe operation of the structure. A physically motivated mathematical framework aimed at the prediction of the serviceability performance of such kind of structures is herein presented and discussed. Piles are idealized as uniaxial nonlinear elements characterized by two yielding loads, one in compression and one in uplift, while pile-to-pile interaction effects are modeled by means of superposition, through an approximate solution. The axial load–moment capacity of the pile group is preliminary determined from a recent closed form, exact solution based on upper and lower bound theorems, allowing the analysis to be performed under load control. The model is capable of accounting for the dependence of the moment–rotation response from the dead load of the structure and the 'coupling effect' between generalized loads and displacements. The prediction performance of the proposed calculation method is validated against both numerical and experimental benchmarks. Finally, a parametric study allowed to assess the importance of pile-to-pile interaction on the foundation response under eccentric loads. [ABSTRACT FROM AUTHOR]

Social conditions can alter the allocation of resources to reproductive traits. For example, an increase in social density during development is frequently associated with an increase in the testes mass of males. Sperm competition theory assumes that increased investment in testes should come at the expense of investing into precopulatory traits, such as sexually selected weaponry. However, much remains unknown about the role of the social context on the concurrent, relative investment in both testes and weapons. We found that the leaf‐footed cactus bug, Narnia femorata (Hemiptera: Coreidae), grew nearly 20% larger testes when raised in high social densities. In addition to manipulating social density, we used autotomy (limb loss) to limit investment in their hindlimb weapon during development. At low densities, we found that those that lost a weapon during development grew larger testes by adulthood, supporting previous work demonstrating a weapons–testes trade‐off. However, at high social densities, males that dropped a hindlimb did not grow larger testes, though testes were already large at this density. These results underscore the importance of the social context to resource allocation patterns within the individual. [ABSTRACT FROM AUTHOR]

Past research indicates that people favor, and behave more morally toward, human ingroup than outgroup members. People showed a similar pattern for responses toward robots. However, participants favored ingroup humans more than ingroup robots. In this study, I examine if robot anthropomorphism can decrease differences between humans and robots on ingroup favoritism. This paper presents a 2 × 2 × 2 mixed-design experimental study with participants (N = 81) competing on teams of humans and robots. I examined how people morally behaved toward and perceived players depending on players’ Group Membership (ingroup, outgroup), Agent Type (human, robot), and Robot Anthropomorphism (anthropomorphic, mechanomorphic). Results replicated prior findings that participants favored the ingroup over the outgroup and humans over robots—to the extent that they favored ingroup robots over outgroup humans. This paper also includes novel results indicating that patterns of responses toward humans were more closely mirrored by anthropomorphic than mechanomorphic robots.

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How do people treat robot teammates compared to human opponents? Past research indicates that people favor, and behave more morally toward, ingroup than outgroup members. People also perceive that they have more moral responsibilities toward humans than nonhumans. This paper presents a 2×2×3 experimental study that placed participants (N = 102) into competing teams of humans and robots. We examined how people morally behave toward and perceive players depending on players' Group Membership (ingroup, outgroup), Agent Type (human, robot), and participant group Team Composition (humans as minority, equal, or majority within the ingroup compared to robots). Results indicated that participants favored the ingroup over the outgroup and humans over robots – to the extent that they favored ingroup robots over outgroup humans. Interestingly, people differentiated more between ingroup than outgroup humans and robots. These effects generalized across Team Composition. [ABSTRACT FROM AUTHOR]

Past research indicates that people favor, and behave more morally toward, human ingroup than outgroup members. People showed a similar pattern for responses toward robots. However, participants favored ingroup humans more than ingroup robots. In this study, I examine if robot anthropomorphism can decrease differences between humans and robots on ingroup favoritism. This paper presents a 2 × 2 × 2 mixed-design experimental study with participants (N = 81) competing on teams of humans and robots. I examined how people morally behaved toward and perceived players depending on players' Group Membership (ingroup, outgroup), Agent Type (human, robot), and Robot Anthropomorphism (anthropomorphic, mechanomorphic). Results replicated prior findings that participants favored the ingroup over the outgroup and humans over robots—to the extent that they favored ingroup robots over outgroup humans. This paper also includes novel results indicating that patterns of responses toward humans were more closely mirrored by anthropomorphic than mechanomorphic robots. [ABSTRACT FROM AUTHOR]

Objective: Over the last 3 decades, group treatment researchers have become increasingly knowledgeable of the impact of within-group dependency on analyses of group treatment data and of mutual influence processes that occur within therapy groups. Despite these advancements, there remains a lack of consensus on the magnitude of mutual influence, or group effects, in group treatment research. As such, this study sought to estimate the size of group effects on members' posttreatment outcomes by meta-analyzing the intraclass correlation coefficients (ICCs) in group treatment research. In addition, we tested several moderators of the ICC, including outcome type, outcome reactivity, outcome specificity, group format, treatment length, and group size. Method: Using robust variance estimations, we meta-analyzed 169 effect sizes from 37 group treatment studies. Results: Findings indicated an average ICC of 0.06. Group size, group format, treatment length, outcome specificity, and outcome type did not significantly moderate the ICC; however, we did find evidence to suggest that the ICC varies as a function of outcome reactivity, with observer-rated outcome measures resulting in the largest ICC. Conclusion: These findings suggest that interdependence in group treatment research is an important concept both theoretically and statistically. What is the public health significance of this article?: This study found that therapy groups account for 6% of the variability in group treatment outcomes. Outcome reactivity significantly moderated the intraclass correlation coefficient (ICC) in group treatment research, such that the largest ICCs were associated with observer-rated outcome measures. Interdependence in group treatment research is important both theoretically and statistically. [ABSTRACT FROM AUTHOR]

Prior to this study, the long-term thermally-induced mechanical interactions of cyclic nonsymmetrical thermally loaded energy pile groups in soft clay have not been systematically elucidated, particularly with a limited understanding of the interactions among operating and non-operating energy piles, soil, and caps. Observing such a challenge, this paper presents a three-dimensional (3D) thermomechanical finite-element model (FEM), which considers the thermal-dependent behavior at the pile-soil interface and is validated using typical centrifuge tests reported in the literature. Special attention is given to the influence of soil-pile thermal expansion coefficient ratio, pile-soil stiffness ratio, and slab-soil stiffness ratio on the abovementioned interaction. The results indicate that a larger soil-pile thermal expansion coefficient ratio intensifies the interaction between energy piles and the surrounding soil, causing cyclic variations in thermally mobilized friction. With increasing pile-soil stiffness ratios, the differential thermomechanical responses among different piles within a group are enhanced because the toe and shaft resistances mobilized by the cap through nonoperating energy piles are weakened in the interaction process among energy piles, nonoperating energy piles, and the cap. Moreover, the increase in the slab-soil stiffness ratio exacerbates this interaction, strengthening the integrity of the pile groups. [ABSTRACT FROM AUTHOR]

Group aggression influences communication and defense strategies in many social insect communities. Such aggression plays a particularly significant role in the lives of stingless bees, important native Neotropical pollinators, in which the battle for food resources can be deadly and critical to colony survival. However, the effects of group size on individual aggression levels and the spatio-temporal aggression strategy of communal aggressors have not been fully explored. We therefore investigated how group size affects the aggression levels and the spatio-temporal attack strategy (which body parts, and the amount of time spent in attacking each part) in close combats between Trigona spinipes foragers and a natural competitor, Melipona rufiventris. In all trials, T. spinipes foragers competitively excluded M. rufiventris foragers from nearby feeders, exhibiting four levels of aggressive behavior ranging from threat displays to prolonged grappling and decapitation. Surprisingly, aggression levels and spatial strategy corresponded to the size of group attacks. Larger groups of attackers used individually lower aggression levels than small groups of attackers. Smaller groups also attacked appendages linked to escape (legs and wings) with greater frequency than larger groups, which focused on vital central body areas (abdomen, thorax, and head). Increased aggression corresponded to increased risks for attackers and the attacked. All combatants engaging at the highest level of aggression died (100% mortality). Thus the dominance style of T. spinipes may minimize attack risk and maximize victim harm with finely tuned hostility. © Birkhäuser Verlag, 2005.

Abstract Offshore Wind Turbine (OWT) support structures need to satisfy different Limit States (LS) such as Ultimate LS (ULS), Serviceability LS, Fatigue LS and Accidental LS. Furthermore, depending on the turbine rated power and the chosen design (all current designs are soft-stiff), target natural frequency requirements must also be met. Most of these calculations require the knowledge of the stiffnesses of the foundation which, especially in the case of large turbines in intermediate waters (30–60 m), might need to be configured using multiple foundation elements. For this reason, this paper studies, for a homogeneous elastic halfspace, the static stiffnesses of groups of polygonally arranged non-slender suction bucket foundations in soft soils modeled as rigid solid embedded foundations. A set of formulas for correcting the stiffnesses obtained from isolated foundation formulation are proposed. It is shown through the study of several multi-megawatt OWTs that, as expected, group effects becomes more relevant as spacing decreases. Also, group effects are sensitive mainly to shear modulus of soil, foundation shape ratio and diameter, and the number of foundations. The results obtained from the soil-structure system show that ignoring group effects may add significant errors to the estimation of OWT fundamental frequencies and leads to either overestimating or underestimating it by 5%. This highlights the importance of adequately modeling the interaction between elements of closely-separated multi-bucket foundations in soft soils, when current guidelines specify the target fundamental frequency to be at least 10% away from operational 1P and blade passing frequencies (2P/3P frequencies). Highlights • Polygonal multi-bucket foundations are considered for offshore wind turbines. • Closed-form foundation stiffnesses including group effects are proposed. • Group effects are relevant for closely-spaced configurations in soft soils. [ABSTRACT FROM AUTHOR]

The article discusses a study on learning outcomes in an introductory Sociology course in a higher education setting. A quantitative model similar to education production functions is hypothesized. Independent variables include socio-demographic and psychological ones, as well as others pertaining to the learning environment. Learning is measured with the binary categories of "deep" and "surface" outcomes, which are qualitatively different, and are based on the comparison of mind maps drawn by students at the beginning and end of their first semester. Questionnaire data was collected from 264 first-year students of a Social Science Faculty. Significant effects on learning outcome are found for family background, major area of study, and teacher's gender. [ABSTRACT FROM AUTHOR]

Students in Brazil are typically assigned to classes based on the age ranking in their cohort. I exploit this rule to estimate how fifth-grade students' achievement in mathematics is affected when they are in classes with older peers. I find that being assigned to the older class leads to a drop in maths scores of about 0.4 of a standard deviation for students at the cut-off. I provide evidence that heterogeneity in age is an important factor behind this effect. Information on teaching practices and student behaviour sheds light on how class heterogeneity harms learning. [ABSTRACT FROM AUTHOR]

The article discusses a study on learning outcomes in an introductory Sociology course in a higher education setting. A quantitative model similar to education production functions is hypothesized. Independent variables include socio-demographic and psychological ones, as well as others pertaining to the learning environment. Learning is measured with the binary categories of “deep” and “surface” outcomes, which are qualitatively different, and are based on the comparison of mind maps drawn by students at the beginning and end of their first semester. Questionnaire data was collected from 264 first-year students of a Social Science Faculty. Significant effects on learning outcome are found for family background, major area of study, and teacher’s gender.

• Mechanical modelling of structural joints is in line with Eurocode 3 and 4. • An innovative mechanical model overcomes the limitations of the existing spring models. • Group effects in steel plate components can be mechanically characterised. • Shear force variation in the panel zone affects the response of steel joints. • Implementing a mechanical model as a macro-element in FE software becomes feasible. An innovative mechanical model for the characterisation of structural steel joints is presented in this paper. The model relies on the so-called "component method" to simulate the joints through an assembly of extensional springs and rigid elements. The proposed approach solves the inconsistencies met in the existing spring models and allows bypassing the analytical assembly procedure prescribed by the current version of Eurocode 3 for the prediction of joints' behaviour. Key features systematically disregarded in classical spring models, i.e., the group effects and the variation of shear forces on the height of the column web panel, are incorporated in the proposed mechanical model. The latter allows predicting the behaviour of steel joints respecting the European normative provisions yet based on mechanical criteria only. Comparisons with experimental and analytical results show the model's code compliance and prove its accuracy in characterising the actual behaviour of structural joints. [ABSTRACT FROM AUTHOR]

Prior to this study, no simplified yet rational methods were available for estimating the vertical displacements of energy pile groups subjected to thermal loads. Observing such a challenge, the goal of this study has been threefold: (i) to extend the interaction factor concept from the framework of conventional pile groups to that of energy pile groups, (ii) to present charts for the analysis of the displacement interaction between two identical energy piles over a broad range of design conditions, and (iii) to propose, apply and validate the interaction factor method for the displacement analysis of energy pile groups. [ABSTRACT FROM AUTHOR]

A sizable body of research has examined BIRG, or Basking in Reflected Glory, as the psychological process of associating with the successes of others. A sample of 253,188 tweets related to the 2014 Scottish Independence Referendum were collected leading up to and following the vote. Results support BIRG processes on the part of anti-independence tweeters, and Cutting Off Reflected Failure (CORF) responses by those favoring independence. Evidence does not support the notion that CORF was attenuated by high involvement. [ABSTRACT FROM PUBLISHER]

Integrating ground heat exchanger elements into concrete piles is now considered as an efficient energy solution for heating/cooling of buildings. In addition to the static load of buildings, the concrete piles also undergo a cycle of thermal deformation. In the case of single energy pile, calculation methods already exist and permit to perform a proper geotechnical design. In the case of energy pile group, the thermo-mechanical interactions within the group are more complex. Very few experimental results on the energy pile group are available so that numerical analysis can be an interesting way to provide complementary results about their behavior. This paper deals with a numerical analysis including a comparison between a single energy pile and an energy pile group with different boundary conditions at the pile head. In order to take into account the stress reversal induced by the thermal expansions and contractions, a cyclic elastoplastic constitutive model is introduced at the soil-pile interface. The analysis aims to give some insights about the long-term cyclic interaction mechanisms in the energy pile group. Based on this qualitative study, some guidance can be brought for the design of energy piles in the case where group effects should be considered. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Oil storage tanks are usually arranged in groups in tank farms, and this configuration may affect their buckling and postbuckling strength under wind loads. The assessment of wind action on tank structures is performed in this work by means of wind tunnel experiments to evaluate the pattern of pressure distribution for a tank which is shielded by another tank under various configurations and separation between them. The experimental results show significant changes in pressures due to shielding effects. In a second stage the structural response under the pressures previously evaluated is performed by finite element analysis using both linear bifurcation and geometrically nonlinear analysis. Results of two-tank interaction are compared with those of an isolated tank. Based on the results, it is concluded that the changes in wind pressures due to group effects induce changes in buckling loads and in the associated deflected patterns. [ABSTRACT FROM AUTHOR]

We assess absolute magnitudes, relative importance, and intertemporal differences in firm, industry, and business group effects in explaining the variance of Indian manufacturing firms' profitability over the 26-year period between 1980- 1981 and 2005-2006. We stratify the data by institutional phases to place emphasis on the role of changing institutional factors in an emerging economy: first as a regime of command and control transits to partial liberalization (between 1985 and 1991) and then to an open competitive market economy (after 1991); thereafter, financial reforms occur, followed by legal reforms. We find that liberalization significantly affects and alters the relative importance of firm, industry, and group effects. Firm effects are always important, whether in a command and control regime, with benefits accruing from protectionism and political rent seeking, or in liberalized periods where firm-specific capabilities and dynamic efficiencies are valued. Industry effects are significant in the command and control regime, when mandatory sector placement benefits firms in industries with superior profits, and in the liberalized period, when the choice of the industry segment in which to operate is open to firms. Thereafter, industry effects dissipate. Business group effects matter in explaining profitability variances. Group effects' magnitudes, however, do not change significantly over time. [ABSTRACT FROM AUTHOR]

The dominant approach in investigating the individual reliability for event-related potentials (ERPs) is to extract peak-related features at electrodes showing the strongest group effects. Such a peak-based approach implicitly assumes ERP components showing a stronger group effect are also more reliable, but this assumption has not been substantially validated and few studies have investigated the reliability of ERPs beyond peaks. In this study, we performed a rigorous evaluation of the test-retest reliability of ERPs collected in a multisensory and cognitive experiment from 82 healthy adolescents, each having two sessions. By comparing group effects and individual reliability, we found that a stronger group-level response in ERPs did not guarantee higher reliability. A perspective of neural oscillation should be adopted for the analysis of reliability. Further, by simulating ERPs with an oscillation-based computational model, we found that the consistency between group-level ERP responses and individual reliability was modulated by inter-subject latency jitter and inter-trial variability. The current findings suggest that the conventional peak-based approach may underestimate the individual reliability in ERPs and a neural oscillation perspective on ERP reliability should be considered. Hence, a comprehensive evaluation of the reliability of ERP measurements should be considered in individual-level neurophysiological trait evaluation and psychiatric disorder diagnosis. [ABSTRACT FROM AUTHOR]

The author shares some lessons learned from a lifetime of working with and thinking about groups. Three types of groups are described, including the impact they have on the development of the members living within them. Transactional analysis is considered in terms of its contributions to understanding the processes involved in all of our groups. [ABSTRACT FROM AUTHOR]

Social interactions in animal groups can buffer environmental stress and may enhance survival under unfavourable conditions. In the present study, the impact on starvation endurance of social group, access to larvae and cold shock is studied in the ant Temnothorax nylanderi Förster. Resource sharing is expected to lead to grouped workers surviving longer than isolated ones. Access to larvae may increase longevity if larvae serve as food, or may interfere with survival if they induce caring behaviour in workers. Cold shock serves as a stress factor and a negative influence on survival is expected. The results show that isolated workers have a shorter lifespan than grouped workers, which in turn live for a shorter period than grouped workers with larvae. Beneficial 'group effects' contribute to group survival and the presence of larvae increases worker survival because the workers presumably feed on the larvae. Thus, improved starvation endurance may reflect an additional benefit of a social lifestyle. Moreover, variance in survival is lower for grouped workers than for isolated workers: group members not only demonstrate improved survival, but also smaller within-group differences. Although a negative influence on survival is the expected outcome, this type of thermal stress is found to have no direct impact on starvation endurance other than moderating the differences between isolated and grouped workers. [ABSTRACT FROM AUTHOR]

We consider the economic and non-economic determinants of well-being across Europe and ask what level of geographical aggregation (for example, individual, regional or national) matters for individual well-being and whether the drivers of well-being differ within and between these different levels. Our results show a more heterogenous set of drivers for individual well-being across regions in Europe than previously described. Not only are individual-level effects significant, but so too are regional factors. In particular, absolute regional factors dominate the effect of an individual's position relative to their region for certain non-economic variables. The significance of these non-economic factors changes depending on the sample of countries considered, but in each case the regional effects dominate for those variables that are significant. [ABSTRACT FROM PUBLISHER]

The Social Facilitation Effect shows performance on many simple tasks is enhanced by crowds of onlookers or co-actors (others performing the same activity). Previous experimental research has shown that Electronic Gaming Machine (EGM) betting behavior is intensified by the belief that others are gambling along with the subject (Rockloff and Dyer, J Gambl Stud 23(1):1-12, 2007). The present study extends these findings by simulating crowds of differing sizes using a fake video-conference along with a live confederate who gambles concurrently with the subjects. Fifty-four male and 81 female subjects aged 18-82 ( M = 46.9, SD = 16.7) played a laptop simulated 3-reel EGM using a $20 stake in 3 conditions: (1) alone, (2) in a simulated group of 5 persons plus 1 live confederate, or (3) in a simulated group of 25 persons plus 1 live confederate. The EGM outcomes were rigged with a fixed 20 trial winning sequence followed by an indefinite losing sequence. As hypothesised, gambling intensity, as measured by trials played, speed of betting and final payouts, was progressively greater with larger crowd sizes ( P < .05). In contrast, bet-size was slightly lower with larger crowds. The results suggest that gambling venues with more players tend to increase gambling persistence and contribute to greater long term monetary losses. [ABSTRACT FROM AUTHOR]

Group treatment data are nested by design, that is, clients nested in groups. Dependence associated with the nesting of group intervention data can inflate Type I error rates, which poses unique challenges to group treatment researchers. This article evaluates the extent and variability of dependence in data taken from 3 previously published randomized clinical trials of group psychotherapy. Three methods of assessing dependence by calculating intraclass correlation coefficients (p) were examined. Results showed great variability in ps across studies, across methods of calculating p, and across outcome variables. The distribution of ps suggested that the amount of dependence in the data was moderate. Two methods of addressing dependence in grouped treatment data through multilevel modeling were used. These methods resulted in minimally compromised statistical power compared with results from uncorrected data. These 2 methods may allow researchers to reliably assess their group treatments. Group intervention researchers are encouraged to consider their assumptions and conceptualizations of treatment change, and to choose corresponding methods of assessing for and addressing p. [ABSTRACT FROM AUTHOR]

We report the results of three randomized experiments designed to assess whether participants' political attitudes are affected by the prediscussion opinions of their discussion mates. The experiments took place during three multisite Deliberative Polls in 2004 and 2005. Participants discussed current political issues within 330 groups of approximately 10 people each. Because the composition of the groups was determined randomly within each location, the demographic and ideological complexion of the discussion groups varied randomly. This paper examines the effects of randomly varying group composition on political opinions expressed after daylong discussion. We find only sporadic evidence of group composition effects. These results run counter to—or at least qualify—a substantial body of theory and laboratory evidence on the influence of group discussion. [ABSTRACT FROM AUTHOR]

[Display omitted] • Overwintering lady beetle aggregations reduce per capita metabolic rates. • Aggregations during winter show a hypometric metabolic-mass scaling relationship. • Locomotor activity partly explains metabolic savings, but only at low temperatures. Energy conservation is linked to survival and fitness of overwintering ectotherms, and is particularly critical in winter. Although many insects overwinter individually, some form aggregations with conspecifics. Aggregations cause metabolic suppression in some insects, but the effect of aggregations on metabolic rates and energy use in overwintering aggregations remains underexplored. The convergent ladybeetle (Hippodamia convergens) overwinters in massive aggregations, making it an ideal system for testing the effect of aggregation size on metabolic rates in overwintering insects. We measured metabolic rates of beetle aggregations of 1, 10, 25, and 50 individuals using stop-flow respirometry across two ecologically relevant temperatures, and measured locomotor activity as one possible driver of group effects on metabolic rate. Metabolic rates per beetle decreased with increasing aggregation size at both temperatures, but was more pronounced at low temperatures. Metabolic rates scaled hypometrically with mass, with deeper response at cool temperatures. Activity decreased with aggregation size, but only at low temperatures. These results suggest that individuals within aggregations enter a deeper metabolically inactive state that single individual beetles cannot achieve, which is partly but not completely explained by a reduction in locomotor activity. This group strategy for energy conservation may provide an additional selective advantage for the evolution of large overwintering aggregations. [ABSTRACT FROM AUTHOR]

The authors explored the group as a source of change in mindfulness-based stress reduction (MBSR). Participants consisted of 606 adults in 59 groups who completed an 8-week MBSR program. The authors examined change in the General Symptom Index (GSI) of the Symptom Checklist-90-Revised and the Medical Symptom Checklist (MSC) from pre- to postintervention. Multilevel models were used to examine the extent to which groups differed in the amount of change reported by the participants. After controlling for pretreatment severity, group accounted for 7% of the variability in the GSI and 0% in the MSC. The authors discuss the implications of these findings for the practice of MBSR as well as for research investigating the effects of MBSR and other programs or psychotherapies. [ABSTRACT FROM AUTHOR]