No abstract

On the basis of the connectionist model of leadership, we examined perceptions of leadership as a function of the contextual factors of race (Asian American, Caucasian American) and occupation (engineering, sales) in 3 experiments (1 student sample and 2 industry samples). Race and occupation exhibited differential effects for within- and between-race comparisons. With regard to within-race comparisons, leadership perceptions of Asian Americans were higher when race-occupation was a good fit (engineer position) than when race-occupation was a poor fit (sales position) for the two industry samples. With regard to between-race comparisons, leadership perceptions of Asian Americans were low relative to those of Caucasian Americans. Additionally, when race-occupation was a good fit for Asian Americans, such individuals were evaluated higher on perceptions of technical competence than were Caucasian Americans, whereas they were evaluated lower when race-occupation was a poor fit. Furthermore, our results demonstrated that race affects leadership perceptions through the activation of prototypic leadership attributes (i.e., implicit leadership theories). Implications for the findings are discussed in terms of the connectionist model of leadership and leadership opportunities for Asian Americans.

The authors examined the validity of observer ratings (supervisor, coworker, and customer) and selfratings of personality measures. Results based on a sample of 105 sales representatives supported the 2 hypotheses tested. First, supervisor, coworker, and customer ratings of the 2 job-relevant personality dimensions-conscientiousness and extraversion-were valid predictors of performance ratings, and the magnitude of the validities were at least as large as for self-ratings. Second, supervisor, coworker, and customer ratings accounted for significant variance in the criterion measure beyond self-ratings alone for the relevant dimensions. Overall, the results suggest that validities of personality measures based on self-assessments alone may underestimate the true validity of personality constructs.

We examined the eVect of similarity on performance ratings in two data sets (peers and supervisors). Surprisingly, there was minimal support for a relationship between relational personality (i.e. actual similarity on dimensions of the Five-Factor Model of personality relevant for sales positions-extraversion, conscientiousness, and emotional stability) and performance ratings in either data set. However, perceived similarity in these same dimensions related strongly to performance ratings. Furthermore, the results indicated no support for interpersonal familiarity as a moderator of the relationship between relational personality and perceived personality similarity. Finally, results provided moderate support for liking as a mediator of the perceived personality similarity-performance rating relationship. Implications of the results for future research and practice are discussed.

Late-onset fragility fractures are a common complication following radiotherapy for metastatic disease and soft tissue sarcomas. Using a murine hindlimb focal irradiation model (RTx), we quantified time-dependent changes in osteoclasts and mineral apposition rate (MAR). Mice received either a single, unilateral 5 Gy exposure or four fractionated doses (4x5 Gy). Osteoclast numbers and MAR were evaluated histologically at 1, 2, 4, 8, 12, and 26 weeks post-RTx. Radiation induced an early, transient increase in osteoclasts followed by long-term depletion. Increased osteoclast numbers correlated temporally with trabecular resorption; the resorbed trabeculae were not later restored. Radiotherapy did not attenuate MAR at any time point. A transient, early increase in MAR was noted in both RTx groups, however, the 4x5 Gy group exhibited an unexpected spike in MAR eight weeks. Persistent depletion of osteoclasts permitted anabolic activity to continue unopposed, resulting in cortical thickening. These biological responses likely contribute to post-radiotherapy bone fragility via microdamage accumulation and matrix embrittlement in the absence of osteoclastic remodeling, and trabecular resorption-induced decrease in bone strength. The temporal distribution of osteoclast numbers suggests that anti-resorptive therapies may be of clinical benefit only if started prior to radiotherapy and continued through the following period of increased osteoclastic remodeling.