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61.
In laboratory experiments conducted to compare the kairomonal activity forMicroplitis croceipes (Cresson) of frass fromHeliothis zea (Boddie) larvae fed on different host plants,M. croceipes females responded to extracts of frass from larvae reared on cotton or soybeans but not on corn. The lack of response to frass from larvae reared on corn was shown to be a result of a lack of some appropriate chemical(s) in the corn.Lepidoptera: Noctuidae.Hymenoptera: Braconidae.In cooperation with the University of Georgia College of Agriculture Experiment Stations, Coastal Plain Station, Tifton, Georgia 31793. Accepted for publication February 9, 1981.Mention of a proprietary product in this paper does not constitute an endorsement by this product by the USDA.  相似文献   
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Centrifugal fans are often integrated into thermal management solutions for a range of applications. Consequently, centrifugal fan designs can be subjected to varying environmental conditions, many of which can alter fan performance characteristics and ultimately influence the heat transfer performance of the cooling solution. Global cross flows are a commonly encountered practical operating condition, particularly in the cooling of electronics. Air-cooled electronic enclosures often incorporate miniature centrifugal fans to maintain reliable component operating temperatures at a local level, while larger system level fans are used to simultaneously control the ambient temperature within the enclosure. This type of operating condition has been investigated by introducing a uniform crossing air flow above a centrifugal fan inlet. Two scaled miniature centrifugal fan designs were selected to fundamentally assess the influence on local velocity field and heat transfer performance. This was achieved experimentally using Particle Image Velocimetry, and a combined infrared and heated-thin-foil technique developed for the accurate measurement of local heat transfer coefficients. the introduction of a crossing air flow above the fan inlet indirectly reduced both the local and global thermal performance of the centrifugal fan, and the resultant distorted inflow shifted the surface heat transfer distribution at the fan outlet from an axisymmetric to asymmetric profile. However, strategic positioning of components relative to a centrifugal fan can maintain the average component heat transfer coefficient at a similar level to a case without any cross flow. Results also indicate issues associated with the implementation of miniature centrifugal fan designs into crossing air flow environments, with reductions in thermal performance of over 30% observed.  相似文献   
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The authors examined cultural and individual differences in the relation between daily events and daily satisfaction. In a preliminary study, they established cross-cultural equivalence of 50 daily events. In the main study, participants in the United States, Korea, and Japan completed daily surveys on the 50 events and daily satisfaction for 21 days. The multilevel random coefficient model analyses showed that (a) the within-person association between positive events and daily satisfaction was significantly stronger among Asian American, Korean, and Japanese participants than among European American participants and (b) the within-person association between positive events and daily satisfaction was significantly weaker among individuals high in global life satisfaction than among those low in global life satisfaction. The findings demonstrate a weaker effect of positive events on daily well-being among individuals and cultures high in global well-being. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Comprehending and debugging computer programs are inherently difficult tasks. The current approach to building program execution and debugging environments is to use exclusively visual stimuli on programming languages whose syntax and semantics has often been designed without empirical guidance. We present an alternative: Sodbeans, an open-source integrated development environment designed to output carefully chosen spoken auditory cues to supplement empirically evaluated visual stimuli. Originally designed for the blind, earlier work suggested that Sodbeans may benefit sighted programmers as well. We evaluate Sodbeans in two experiments. First, we report on a formal debugging experiment comparing (1) a visual debugger, (2) an auditory debugger, and (3) a multimedia debugger, which includes both visual and auditory stimuli. The results from this study indicate that while auditory debuggers on their own are significantly less effective for sighted users when compared with visual and multimedia debuggers, multimedia debuggers might benefit sighted programmers under certain circumstances. Specifically, we found that while multimedia debuggers do not provide instant usability, once programmers have some practice, their performance in answering comprehension questions improves. Second, we created and evaluated a pilot survey analyzing individual elements in a custom programming language (called HOP) to garner empirical metrics on their comprehensibility. Results showed that some of the most widely used syntax and semantics choices in commercial programming languages are extraordinarily unintuitive for novices. For example, at an aggregate level, the word for , as in a for loop, was rated reliably worse than repeat by more than 673% by novices. After completing our studies, we implemented the HOP programming language and integrated it into Sodbeans.  相似文献   
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It looks like 2000 could be a big year for public key infrastructure (PKI). Five leading vendors this week announced the formation of the PKI Forum with the intention of moving the technology forward as an E-commerce enabler.  相似文献   
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