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Studies were conducted in 1994 and 1995 to examine the effects of a range of action thresholds for managing Bemisia tabaci (Gennadius) Biotype B (= B. argentifolii BellowsPerring) with insecticides in cotton on populations of arthropod predators in Imperial Valley, CA, and Maricopa, AZ. Application of insecticides significantly reduced population densities of spiders, Geocoris punctipes (Say), G. pallens (Stål), Orius tristicolor (White), Nabis alternatus Parshley, Zelus renardii Kolenati, Hippodamia convergens Guerin-Méneville, Spanogonicus albofasciatus (Reuter), Drapetis sp., and Chrysoperla carnea Stephens in one or both years and sites compared with untreated controls. Use of higher B. tabaci thresholds conserved some species and groups relative to lower thresholds. Stepwise regression analyses indicated that reductions in predator populations were generally influenced more strongly by the timing of the first insecticide application than by the total number of sprays necessary to maintain suppression of the pest below any given action threshold. A predation index, which weights the importance of each predator species based on their known frequency of predation on B. tabaci and another key pest, Pectinophora gossypiella (Saunders), was developed and analyzed. Patterns were similar to results based on changes in abundance alone, but the index generally revealed less severe effects of insecticides on overall predator function. The current action threshold for conventional insecticidal control of B. tabaci in Arizona and southern California is five adults per leaf. Results here suggest that predator conservation may be enhanced by raising the initial threshold to delay the first application or initially using more selective materials such as insect growth regulators. more...

The authors argue that individuals regulate perceptions of their relationships in a self-protective way, finding virtue in their partners only when they feel confident that their partners also see virtues in them. In 4 experiments, the authors posed an acute threat to low and high self-esteem individuals' feelings of self-worth (e.g., guilt about a transgression, fears of being inconsiderate or intellectually inept). They then collected measures of confidence in the partner's positive regard and acceptance (i.e., reflected appraisals) and perceptions of the partner. The results revealed that low self-esteem individuals reacted to self-doubt with heightened doubts about their partners' regard, which then tarnished impressions of their partners. In contrast, high self-esteem individuals reacted to self-doubts by becoming more convinced of their partners' continued acceptance, using their relationships as a resource for self-affirmation. more...

There has long been interest in describing emotional experience in terms of underlying dimensions, but traditionally only two dimensions, pleasantness and arousal, have been reliably found. The reasons for these findings are reviewed, and integrating this review with two recent theories of emotions (Roseman, 1984; Scherer, 1982), we propose eight cognitive appraisal dimensions to differentiate emotional experience. In an investigation of this model, subjects recalled past experiences associated with each of 15 emotions, and rated them along the proposed dimensions. Six orthogonal dimensions, pleasantness, anticipated effort, certainty, attentional activity, self-other responsibility/control, and situational control, were recovered, and the emotions varied systematically along each of these dimensions, indicating a strong relation between the appraisal of one's circumstances and one's emotional state. The patterns of appraisal for the different emotions, and the role of each of the dimensions in differentiating emotional experience are discussed. more...

Recent research has suggested strong relations between characteristic patterns of appraisal along emotionally relevant dimensions and the experience of specific emotions. However, this work has relied primarily upon ratings of remembered or imagined past events associated with the experience of relatively pure emotions. The present investigation is an attempt to examine cognitive appraisals and emotions during an emotional event in which subjects experience complex emotional blends. Subjects described both their cognitive appraisals and their emotional states just before taking a college midterm examination and, again, immediately after receiving their grades on the exam. Analysis of the ratings revealed that at both times the majority of subjects who felt emotion experienced complex blends of two or more emotions. Correlation and regression analyses indicated that even in the context of these blends, patterns of appraisal, highly similar to those discovered in our earlier research on remembered emotions (SmithEllsworth, 1985), characterized the experience of emotions as they were actually felt. more...

Facial expression and emotional stimuli were varied orthogonally in a 3 x 4 factorial design in order to test whether facial expression is necessary or sufficient to influence emotional experience. Subjects watched a film eliciting fear, sadness, or no emotion, while holding their facial muscles in the position characteristic of fear or sadness, or in an effortful but nonemotional grimace; those in a fourth group received no facial instructions. The subjects believed that the study concerned subliminal perception and that the facial positions were necessary to prevent physiological recording artifacts. The films had powerful effects on reported emotions, the facial expressions none. Correlations between facial expression and reported emotion were zero. Sad and fearful subjects showed distinctive patterns of physiological arousal. Facial expression also tended to affect physiological responses in a manner consistent with an effort hypothesis. more...