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51.
Cuticular hydrocarbons of the eastern subterranean termite,Reticulitermes flavipes (Kollar) (Isoptera: Rhinotermitidae) 总被引:2,自引:2,他引:0
Major cuticular hydrocarbon components in several castes ofReticulitermes flavipes (Kollar) have been identified and quantitated. Types of hydrocarbons present includen-alkanes, 2-methylalkanes, 3-methylalkanes, 5-methylalkanes, an alkene, and an alkadiene, with a range in carbon numbers from C21 to C26, This is the first report on insect cuticular hydrocarbons in which both 2- and 3-methylalkanes are present, as well as the first report of an insect with a conjugated alkadiene. 相似文献
52.
53.
Waddill Paula J.; McDaniel Mark A.; Einstein Gilles O. 《Canadian Metallurgical Quarterly》1988,80(4):457
Examined the possibility that effects of illustrations on memory for text will vary as a function of the nature of the text (narrative vs expository) and as a function of the type of information depicted in the illustrations (details conveyed in a particular proposition vs information conveyed by the interrelationship of several propositions). In Exp 1, 72 college subjects read a fairy tale or an expository text accompanied by no pictures (control condition), by pictures illustrating details from the text, or by pictures illustrating relations among propositions in the text. Pictures effectively increased recall only when they depicted the type of information for which the text type presumably invited processing (i.e., details for the expository passage, relations for the fairy tale). In Exp 2, 72 college subjects were instructed to attend to the type of information not normally encoded from each text type. With the addition of these special processing instructions, illustrations enhanced memory for not normally encoded information in the fairy tale; a tendency toward the same trend occurred in the expository passage. Recall of information for which the text type encouraged processing continued to be enhanced. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
54.
McDaniel Michael A.; Whetzel Deborah L.; Schmidt Frank L.; Maurer Steven D. 《Canadian Metallurgical Quarterly》1994,79(4):599
Presents the findings of a project investigating the validity of the employment interview. Analyses are based on 245 coefficients derived from 86,311 individuals. Results show that interview validity depends on the content of the interview (situational, job related, or psychological), how the interview is conducted (structured vs unstructured; board vs individual), and the nature of the criterion (job performance, training performance, and tenure; research or administrative ratings). Situational interviews had higher validity than did job-related interviews, which, in turn, had higher validity than did psychologically based interviews. Structured interviews were found to have higher validity than unstructured interviews. Interviews showed similar validity for job performance and training performance criteria, but validity for the tenure criteria was lower. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
Terrestrial raptors which feed on upland hunted game species may increase their risk to lead exposure and lead poisoning by ingesting lead shot found in the tissues of prey. Lead exposure in 225 individuals of nineteen species of terrestrial raptors, collected as carcasses in southern Ontario from 1995-2001, was examined through the analysis of bone, liver and kidney tissues. In this study, one red-tailed hawk contained liver lead concentrations and exhibited signs consistent with lead poisoning. Liver and kidney concentrations of one turkey vulture were also significantly higher than that associated with subclinical effects. This same bird, plus another turkey vulture and a northern harrier, had elevated bone lead concentrations (>10 microg/g dw) associated with possible toxicity. Turkey vultures had the highest mean concentrations of lead in bone and kidney compared to other raptor species. While it appeared only a single bird suffered acute lead poisoning, lead levels exceeded threshold concentrations associated with subclinical or acute toxicity in 4 of 225, almost 2%, of terrestrial raptors assessed. Given the association between lead exposure in raptors and hunting of game species reported in other studies, the continued use of lead shot for upland hunting in Ontario likely remains as one of the primary sources of lead and a continued risk to these birds of prey. 相似文献
56.
Cawthorne W.R. Famouri P. Jingdong Chen Clark N.N. McDaniel T.I. Atkinson R.J. Nandkumar S. Atkinson C.M. Petreanu S. 《Vehicular Technology, IEEE Transactions on》1999,48(6):1797-1802
This paper examines the design and operation of a generation system that utilizes a linear crankless internal combustion engine in conjunction with a linear alternator. This system directly utilizes the linear motion of the piston to drive the alternator rather than first converting to rotary motion. The result is a more compact, reliable, and efficient unit as the system has only one moving part, making the system ideal for use in series hybrid electric vehicles. This paper describes the overall system design as well as the subsystems including the engine and alternator. A dynamic simulation is then presented which utilizes the model developed to determine the output characteristics of the system. The prototype system was successfully tested, and experimental results are also included 相似文献
57.
Objective
To analyse the implications of Philip Morris USA''s (PM''s) overtures toward tobacco control and other public health organisations, 1995–2006.Data sources
Internal PM documents made available through multi‐state US attorneys general lawsuits and other cases, and newspaper sources.Methods
Documents were retrieved from several industry documents websites and analysed using a case study approach.Results
PM''s Project Sunrise, initiated in 1995 and proposed to continue through 2006, was a long‐term plan to address tobacco industry delegitimisation and ensure the social acceptability of smoking and of the company itself. Project Sunrise laid out an explicit divide‐and‐conquer strategy against the tobacco control movement, proposing the establishment of relationships with PM‐identified “moderate” tobacco control individuals and organisations and the marginalisation of others. PM planned to use “carefully orchestrated efforts” to exploit existing differences of opinion within tobacco control, weakening its opponents by working with them. PM also planned to thwart tobacco industry delegitimisation by repositioning itself as “responsible”. We present evidence that these plans were implemented.Conclusion
Sunrise exposes differences within the tobacco control movement that should be further discussed. The goal should not be consensus, but a better understanding of tensions within the movement. As the successes of the last 25 years embolden advocates to think beyond passage of the next clean indoor air policy or funding of the next cessation programme, movement philosophical differences may become more important. If tobacco control advocates are not ready to address them, Project Sunrise suggests that Philip Morris is ready to exploit them. 相似文献58.
Rose Nathan S.; Rendell Peter G.; McDaniel Mark A.; Aberle Ingo; Kliegel Matthias 《Canadian Metallurgical Quarterly》2010,25(3):595
Young (ages 18–22 years) and older (ages 61–87 years) adults (N = 106) played the Virtual Week board game, which involves simulating common prospective memory (PM) tasks of everyday life (e.g., taking medication), and performed working memory (WM) and vigilance tasks. The Virtual Week game includes regular (repeated) and irregular (nonrepeated) PM tasks with cues that are either more or less focal to other ongoing activities. Age differences in PM were reduced for repeated tasks, and performance improved over the course of the week, suggesting retrieval was more spontaneous or habitual. Correlations with WM within each age group were reduced for PM tasks that had more regular or focal cues. WM (but not vigilance) ability was a strong predictor of irregular PM tasks with less focal cues. Taken together, these results support the hypothesis that habitual and focally cued PM tasks are less demanding of attentional resources (specifically, WM), whereas tasks that are more demanding of controlled attentional processes produce larger age differences, which may be attributable to individual differences in WM. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
59.
Kumar Ankit Abhik Choudhury Cheng Qin Sebastian Schulz Malte McDaniel Britta Nestler 《Acta Materialia》2013,61(11):4245-4253
We investigate the lamellar growth of pearlite at the expense of austenite during the eutectoid transformation in steel. To begin with, we extend the Jackson–Hunt-type calculation (previously used to analyze eutectic transformation) to eutectoid transformation by accounting for diffusion in all the phases. Our principal finding is that the growth rates in the presence of diffusion in all the phases are different compared to the case when diffusion in growing phases is absent. The difference in the dynamics is described by a factor ’ρ’ which comprises the ratio of the diffusivities of the bulk and the growing phases, along with the ratios of the slopes of the phase coexistence lines. Thereafter, we perform phase-field simulations, the results of which are in agreement with analytical predictions. The phase-field simulations also reveal that diffusion in austenite as well as ferrite leads to the formation of tapered cementite along with an overall increase in the transformation kinetics as compared to diffusion in austenite (only). Finally, it is worth noting that the aim of present work is not to consider the pearlitic transformation in totality; rather it is to isolate and thereby investigate the influence of diffusivity in the growing phases on the front velocity. 相似文献
60.
Annual losses by mastitis are estimated to be in excess of two billion dollars in the United States. Udder and teat morphologies have been associated with incidences of mastitis without clear conclusion on the closeness. Streak canal diameter was correlated with udder health, but it is difficult to measure. Udder depth and teat-end shape have been associated with udder health. Selection to reduce frequencies of cows with deep udders and flat, disk, or inverted teat ends may reduce mastitis incidence. Heritabilities of udder morphology are moderate to high, and a single score during the lifetime of a cow may be adequate for selection. There is no concensus in the literature on relationships between mastitis and teat size, general teat shape, teat-end lesions, teat pigmentation, or milk flow rate. Different breeds, milking procedures, measures of mastitis, and statistical procedures may account for different conclusions. Genetic approaches to improve mastitis resistance of dairy cattle seem warranted. This paper attempts to summarize evidence dealing with possible physical bases for genetic variation associated with mastitis in dairy cattle. 相似文献