Group consensus in social influence: Type of consensus information as a moderator of majority and minority influence

Three experiments investigated the effect of consensus information on majority and minority influence. Experiment 1 examined the effect of consensus expressed by descriptive adjectives (large vs. small) on social influence. A large source resulted in more influence than a small source, irrespective of source status (majority vs. minority). Experiment 2 showed that large sources affected attitudes heuristically, whereas only a small minority instigated systematic processing of the message. Experiment 3 manipulated the type of consensus information, either in terms of descriptive adjectives (large, small) or percentages (82%, 18%, 52%, 48%). When, consensus was expressed in terms of descriptive adjectives, the findings of Experiments 1 and 2 were replicated (large, sources were more influential than small sources), but when. consensus was expressed, in terms of percentages, the majority was more influential than the minority, irrespective of group consensus.

Talking to children: The within-classroom nature of everyday adult language in the early childhood educational environment

Group-size effects, as changes in the adult language when speaking to individual or multiple children in two- and three-year-olds' Australian childcare centre classrooms were investigated. The language addressed to children by 21 staff members was coded for social (e.g., non-verbal, inferential and pragmatic), and linguistic (e.g., morphological, lexical, syntactic and referential) features. In the two-year-olds' classrooms, minimal differences were found between the language used in dyads (addressed to a single child) and polyads (addressed to more than one child). More extensive group-size effects, particularly in syntactic complexity, were found in the three-year-olds' classrooms. Explanations for the constancy of the adult language input in the younger classrooms, and the changes noted in the older rooms will be discussed in terms of plurality (i.e., more than one listener), methodology, and group-size effects that may be specific to the early childhood educational setting.

Factors affecting the vigilance and flight behaviour of impalas

This study investigated the influences of various natural and anthropogenic factors on the vigilance and flight behaviour of impalas in the Save Valley Conservancy, Zimbabwe, using multivariate statistical techniques. The factor that most significantly affected the proportions of time that individuals spent being vigilant and their rates of vigilance was the position of a focal animal in the group; impalas on the periphery of a group were more vigilant than central impalas. Both measures of vigilance were also negatively related to group size. Males spent more total time being vigilant but females raised their heads more often. Impalas spent more time being vigilant in the late afternoon than in the early morning, when greater than ten metres from cover, and when predators had been nearby within the previous six hours. Impalas spent more time vigilant at the property where more impalas were hunted, possibly reflecting the differences in the intensity of hunting by humans on the two properties. Flight distances at the approach of humans were significantly greater at one property than the other, and were also greater for small groups. Further research into the effects of hunting by humans on animals' antipredator behaviours would provide valuable insights for wildlife managers.

Transmission mode and distribution of parasites among groups of the social lizard Egernia stokesii

We explored patterns of infection of three apicomplexan blood parasites with different transmission mechanisms in 46 social groups across seven populations of the Australian lizard, Egernia stokesii. There was higher aggregation of infections within social groups for Hemolivia, transmitted by ticks, and Schellackia, either tick-transmitted or directly transmitted from mother to offspring, than for Plasmodium, with more mobile dipteran vectors. Prevalence was not related to group size, proximity to other groups or spatial overlap with adjacent groups for any of the parasites. However, for Hemolivia, groups with higher levels of relatedness among adults had higher parasite prevalence. Living in social groups leads to higher risk of infection for parasites with low transmission mobility. An unanswered question is why so few lizard species tolerate these risks to form stable social aggregations.

Not being what you claim to be: impostors as sources of group threat

We examine the notion of impostors within groups, defined in this paper as people who make public claims to an identity while disguising their failure to fulfil key criteria for group membership. In Experiment 1, vegetarians showed heightened levels of negative affect toward vegetarians who ate meat occasionally compared to an authentic vegetarian. In contrast, non-vegetarians saw the impostor to be marginally more likeable than the authentic vegetarian. In Experiments 2 and 3, participants evaluated only a vegetarian who ate meat. Evaluations of the target were influenced by group attachment, such that participants who identified strongly as vegetarians downgraded the target more strongly and experienced more negative affect than did moderate identifiers and non-vegetarians. Participants were also sensitive to the size of the gulf between the target's claims for identity and their behaviour. Thus, targets who made public claims to being a vegetarian but ate meat were evaluated more negatively than were people who kept their claims for identity private (Experiment 2). Similarly, targets who tried to keep their deviant behaviour secret were evaluated more negatively than were people who openly admitted their deviant behaviour (Experiment 3). The reasons why impostors might threaten the integrity of group identities are discussed. Copyright (C) 2003 John Wiley Sons, Ltd.

High-Risk Merkel Cell Carcinoma of the Skin Treated With Synchronous Carboplatin/Etoposide and Radiation: A Trans-Tasman Radiation Oncology Group Study-TROG 96:07

Purpose: The effectiveness of synchronous carboplatin, etoposide, and radiation therapy was prospectively assessed in a group of patients with high-risk Merkel cell carcinoma (MCC) of the skin. Patients and Methods: Patients were eligible if they had disease localized to the primary site and nodes, and were required to have at least one of the following high risk features: recurrence after initial therapy, involved nodes, primary tumor size greater than 1 cm, gross residual disease after surgery, or occult primary with nodes. Radiation was delivered to the primary site and nodes to a dose of 50 Gy in 25 fractions over 5 weeks and synchronous carboplatin (area under the curve, 4.5) and intravenous etoposide 80 mg/m(2) days 1 to 3 was given in weeks 1, 4, 7, and 10. The median age of the group was 67 (range, 43-86) years, and there were 39 males and 14 females. Involved nodes (stage II) were present in 33 cases (62%). The sites involved were head and neck (22 patients), occult primary (13 patients), upper limb (eight patients), lower limb (eight patients), and trunk (two patients). Results: Fifty-three patients were entered between 1996 and 2001. The median potential follow-up was 48 months. There were no treatment related deaths. The 3-year overall survival, locoregional control, and distant control were 76%, 75%, and 76%, respectively. Tumor site and the presence of nodes were factors that were predictive for local control and survival. Multivariate analysis indicated that the major factor influencing survival was the presence of nodes; however, this was not a significant factor in locoregional control. Conclusion: High levels of locoregional control and survival have been achieved with the addition of chemotherapy to radiation treatment for high-risk MCC of the skin. The role of chemoradiotherapy for high-risk MCC warrants further investigation. (C) 2003 by American Society of Clinical Oncology.

Using the effect size to model change in preference values from descriptive health status

Objectives: This pilot study describes a modelling approach to translate group-level changes in health status into changes in preference values, by using the effect size (ES) to summarize group-level improvement. Methods: ESs are the standardized mean difference between treatment groups in standard deviation (SD) units. Vignettes depicting varying severity in SD decrements on the SF-12 mental health summary scale, with corresponding symptom severity profiles, were valued by a convenience sample of general practitioners (n = 42) using the rating scale (RS) and time trade-off methods. Translation factors between ES differences and change in preference value were developed for five mental disorders, such that ES from published meta-analyses could be transformed into predicted changes in preference values. Results: An ES difference in health status was associated with an average 0.171-0.204 difference in preference value using the RS, and 0.104-0.158 using the time trade off. Conclusions: This observed relationship may be particular to the specific versions of the measures employed in the present study. With further development using different raters and preference measures, this approach may expand the evidence base available for modelling preference change for economic analyses from existing data.

Adjusting Body Cell Mass for Size in Women of Differing Nutritional Status

Background: Body cell mass (BCM) may be estimated in clinical practice to assess functional nutritional status, eg, in patients with anorexia nervosa. Interpretation of the data, especially in younger patients who are still growing, requires appropriate adjustment for size. Previous investigations of this general issue have addressed chemical rather than functional components of body composition and have not considered patients at the extremes of nutritional status, in whom the ability to make longitudinal comparisons is of particular importance. Objective: Our objective was to determine the power by which height should be raised to adjust BCM for height in women of differing nutritional status. Design: BCM was estimated by K-40 counting in 58 healthy women, 33 healthy female adolescents, and 75 female adolescents with anorexia nervosa. The relation between BCM and height was explored in each group by using log-log regression analysis. Results: The powers by which height should be raised to adjust BCM,A,ere 1.73. 1.73, and 2.07 in the women, healthy female adolescents, and anorexic female adolescents, respectively. A simplified version of the index, BCM/height(2), was appropriate for all 3 categories and was negligibly correlated with height. Conclusions: In normal-weight women, the relation between height and BCM is consistent with that reported previously between height and fat-free mass. Although the consistency of the relation between BCM and fat-free mass decreases with increasing weight loss, the relation between height and BCM is not significantly different between normal-weight and underweight women. The index BCM/height(2) is easy to calculate and applicable to both healthy and underweight women. This information may be helpful in interpreting body-composition data in clinical practice.

Randomized trial of 8 Gy in 1 versus 20 Gy in 5 fractions of radiotherapy for neuropathic pain due to bone metastases (Trans-Tasman Radiation Oncology Group, TROG 96.05)

Background and purpose: Despite numerous randomized trials investigating radiotherapy (RT) fractionation schedules for painful bone metastases, there are very few data on RT for bone metastases causing pain with a neuropathic component. The Trans-Tasman Radiation Oncology Group undertook a randomized trial comparing the efficacy of a single 8 Gy (8/1) with 20 Gy in 5 fractions (20/5) for this type of pain. Materials and methods: Eligible patients had radiological evidence of bone metastases from a known malignancy with no change in systemic therapy within 6 weeks before or anticipated within 4 weeks after RT, no other metastases along the distribution of the neuropathic pain and no clinical or radiological evidence of cord/cauda equina compression. All patients gave written informed consent. Primary endpoints were pain response within 2 months of commencement of RT and time to treatment failure (TTF). The hypothesis was that 8/1 is at least as effective as 20/5 and the planned sample size was 270 patients. Results: Between February 1996 and December 2002, 272 patients were randomized (8/1:20/5 = 137:135) from 15 centres (Australia 11, New Zealand 3, UK 1). The commonest primary cancers were lung (31%), prostate (29%) and breast (8%); index sites were spine (89%), rib (9%), other (2%); 72% of patients were males and the median age was 67 (range 2989). The median overall survival (95% CI) for all randomized patients was 4.8 mo (4.2-5.7 mo). The intention-to-treat overall response rates (95% Cl) for 8/1 vs 20/5 were 53% (45-62%) vs 61% (53-70%), P = 0.18. Corresponding figures for complete response were 26% (18-34%) vs 27% (19-35%), P = 0.89. The estimated median TTFs (95% CI) were 2.4 mo (2.0-3.3 mo) vs 3.7 mo (3.1-5.9 mo) respectively. The hazard ratio (95% Cl) for the comparison of TTF curves was 1.35 (0.99-1.85), log-rank P = 0.056. There were no statistically significant differences in the rates of re-treatment, cord compression or pathological fracture by arm. Conclusions: 8/1 was not shown to be as effective as 20/5, nor was it statistically significantly worse. Outcomes were generally poorer for 8/1, although the quantitative differences were relatively small. (c) 2004 Elsevier Ireland Ltd. All rights reserved.

The effect of manganese on the grain size of commercial AZ31 alloy

The effect of manganese on gain refinement of a commercial AZ31 alloy has been investigated using an Al-60%Mn master alloy splatter as an alloying additive at 730 degrees C in aluminium titanite crucibles. It is shown that grain refinement by manganese is readily achievable in AZ31. Electron microprobe analyses reveal that prior to the addition of extra manganese the majority of the intermetallic particles found in AZ31 are of the AL(8)Mn(5) type. However, after the addition of extra manganese in the range from 0.1% to 0.8%, the predominant group of intermetallic particles changes to the metastable AlMn type. This leads to a hypothesis that the metastable AlMn intermetallic particles are more effective than Al8Mn5 as nucleation sites for magnesium grains. The hypothesis is supported by the observation that a long period of holding at 730 degrees C leads to an increase in grain size, due probably to the transformation of the metastable AlMn to the stable Al8Mn5. The hypothesis has also been used to understand the mechanism of grain refinement by superheating.

Reduced nephron number and glomerulomegaly in Australian Aborigines: A group at high risk for renal disease and hypertension

Aborigines in remote areas of Australia have much higher rates of renal disease, as well as hypertension and cardiovascular disease, than non-Aboriginal Australians. We compared kidney findings in Aboriginal and non-Aboriginal people in one remote region. Glomerular number and mean glomerular volume were estimated with the disector/fractionator combination in the right kidney of 19 Aborigines and 24 non-Aboriginal people undergoing forensic autopsy for sudden or unexpected death in the Top End of the Northern Territory. Aborigines had 30% fewer glomeruli than non-Aborigines-202000 fewer glomeruli per kidney, or an estimated 404000 fewer per person (P=0.036). Their mean glomerular volume was 27% larger (P=0.016). Glomerular number was significantly correlated with adult height, inferring a relationship with birthweight, which, on average, is much lower in Aboriginal than non-Aboriginal people. Aboriginal people with a history of hypertension had 30% fewer glomeruli than those without-250000 fewer per kidney (P=0.03), or 500000 fewer per person, and their mean glomerular volume was about 25% larger. The lower nephron number in Aboriginal people is compatible with their susceptibility to renal failure. The additional nephron deficit associated with hypertension is compatible with other reports. Lower nephron numbers are probably due in part to reduced nephron endowment, which is related to a suboptimal intrauterine environment. Compensatory glomerular hypertrophy in people with fewer nephrons, while minimizing loss of total filtering surface area, might be exacerbating nephron loss. Optimization of fetal growth should ultimately reduce the florid epidemic of renal disease, hypertension, and cardiovascular disease.

Stage is not a reliable indicator of tumor volume in non-small cell lung cancer: a preliminary analysis of the trans-tasman radiation oncology group 99-05 database

Background: Tumor volume has been shown to be a prognostic factor for the response of some tumors to radiotherapy. TNM stage has prognostic value for patients treated surgically for non-small cell lung cancer (NSCLC), but its value is less clear for patients treated by nonsurgical means. This may be because tumor size is not a consistent determinant of T stage or stage group. As part of the preliminary analyses for the Trans-Tasman Radiation Oncology Group 99-05 study, the authors performed this analysis to determine to what extent stage reflects tumor volume. Methods: In this prospective multicenter observational study, patients had to have histologically proven NSCLC, no evidence of disease beyond the primary site or thoracic lymph nodes, and been planned for radical radiotherapy with or without chemotherapy. Tumor volume measurements were based on computed tomography-based treatment planning images. Results: Four hundred four patients were available for analysis. There was a strong correlation between (log) maximum tumor diameter and (log) tumor volume (r = 0.93, p < 0.001). Although there was a highly significant trend of increasing volume with increasing T stage and stage group, when tumors were categorized into four groups according to increasing volume, there was only 55% concordance with T stage and 67% concordance with stage group. Conclusions: There is limited correlation between tumor size and disease stage in patients with NSCLC. This justifies documentation and investigation of size as a potential prognostic factor independent of stage. Maximum tumor diameter may be an adequate substitute for volume as a measurement of size.