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31.
Microstructural changes due to kinetic demixing within sintered BSCF ceramics (Ba0.5Sr0.5CoxFe1?xO3?δ, x = 0.2 and 0.8: BSCF5528 and BSCF5582, respectively) have been investigated. When the specimens were subjected to 2 A/cm2 at 1000 °C and pO2 = 10?5 atm, there was a significant enhancement of grain growth as well as 2nd phase formation observed in BSCF5528. At the anode, cobalt deficient aggregates within the grains; and, at the cathode, cobalt rich 2nd phase particles were observed on the grain surfaces of the microstructure. Such phenomena were not observed in BSCF5582, even under higher current density (7 A/cm2) and longer delay time. These results were explained by the kinetic demixing/decomposition. 相似文献
32.
Zhang QH Schneidmiller RG Hoover DR Young K Welshons DO Margaryan A Aldrich JR Chauhan KR 《Journal of chemical ecology》2006,32(10):2163-2176
Gas chromatographic–electroantennographic detection (GC–EAD) analysis showed that male antennae of the green lacewing, Chrysopa nigricornis Burmeister, the most common lacewing species in the U.S. Pacific Northwest, consistently responded to two compounds in thoracic extracts of conspecific males: 1-tridecene and (1R,2S,5R,8R)-iridodial. These compounds were not detected in extracts of the abdominal cuticle, and no other antennally active compounds were found in the abdominal samples. In field-trapping experiments, traps baited with iridodial significantly attracted large numbers of C. nigricornis males (both western and eastern forms) during summer and early fall, plus a few individuals of conspecific females only in early fall. Iridodial also attracted males of the goldeneyed lacewing, C. oculata Say, and, to a lesser extent, C. coloradensis Banks males. Methyl salicylate (MS), reported as an attractant for both sexes of C. nigricornis and C. oculata, was inactive by itself at the concentration tested in our study, but in a few instances slightly enhanced the responses of Chrysopa spp. to iridodial. However, MS alone and its binary blend with iridodial seemed to attract the hoverfly, Metasyrphus americanus (Weidemann). 2-Phenylethanol, a reported attractant for another lacewing, Chrysoperla plorabunda (Fitch) [=carnea (Say)], did not capture any lacewings. Our assays indicated that the lacewing pheromone, iridodial, loaded onto either rubber septa or as a binary blend with MS in polyethylene bags could last at least 5 wk in the field during the summer season. Based on this study, a new attractant system for green lacewings is being developed for both domestic and international markets. 相似文献
33.
Alessandra Bordoni Francesca Danesi Dominique Dardevet Didier Dupont Aida S. Fernandez Doreen Gille 《Critical reviews in food science and nutrition》2017,57(12):2497-2525
Inflammation is a major biological process regulating the interaction between organisms and the environment, including the diet. Because of the increase in chronic inflammatory diseases, and in light of the immune-regulatory properties of breastfeeding, the ability of dairy products to modulate inflammatory processes in humans is an important but unresolved issue. Here, we report a systematic review of 52 clinical trials investigating inflammatory markers in relation to the consumption of dairy products. An inflammatory score (IS) was defined to quantitatively evaluate this interaction. The IS was significantly positive for the entire data set, indicating an anti-inflammatory activity in humans. When the subjects were stratified according to their health status, the IS was strongly indicative of an anti-inflammatory activity in subjects with metabolic disorders and of a pro-inflammatory activity in subjects allergic to bovine milk. Stratifying the data by product categories associated both low-fat and high-fat products, as well as fermented products, with an anti-inflammatory activity. Remarkably, the literature is characterized by a large gap in knowledge on bioavailability of bioactive nutrients. Future research should thus better combine food and nutritional sciences to adequately follow the fate of these nutrients along the gastrointestinal and metabolic axes. 相似文献
34.
Alan Messer Anugeetha Kunjithapatham Phuong Nguyen Priyang Rathod Mithun Sheshagiri Doreen Cheng Simon Gibbs 《Pervasive and Mobile Computing》2008,4(6):871-888
The Internet has become an extremely popular source of entertainment and information. But, despite its growing popularity, most websites today are accessed by keyword search via web browsers, making it difficult for home consumers to locate Internet content of interest on their TVs or other devices that lack keyboards. In this paper, we present assistive technologies, enabling users to easily locate Internet content related to the TV program they are watching. Access is enabled via an intuitive user interface on the TV screen or by using a secondary personal device, and thus avoiding disrupting the viewing experience of the other TV users. 相似文献
35.
Qiquan Feng Caspar J. McConville Doreen D. Edwards Daniel E. McCauley Mike Chu 《Journal of the American Ceramic Society》2006,89(3):894-901
The dielectric properties, dopant distributions, and microstructures of BaTiO3 -based multilayer ceramic capacitors (MLCCs) sintered in H2 –N2 –H2 O atmospheres with =10−7.5 Pa (BMX-7.5) and =10−9.5 Pa (BMX-9.5) were studied, and the effects of oxygen partial pressures were analyzed. Dielectric measurements showed that BMX-7.5 had a lower dielectric constant at temperatures above 20°C, but a higher dielectric constant at temperatures below 10°C when compared with BMX-9.5. The coexistence of core–shell and core grains was observed in bright field (BF) transmission electron microscopy images in both types of capacitors. Triple-point and grain boundary phases were observed more frequently in BMX-9.5 than in BMX-7.5, and energy-dispersive X-ray spectrometer point-by-point analysis revealed that these second phases contained high concentrations of dopants such as Si, Y, and Ca. The dopant concentration in the shell regions in BMX-7.5 was higher than that in similar regions in BMX-9.5. Smeared and twisted grain boundaries with fringes observed in both types of MLCCs indicated that the shell regions in both samples were formed either by diffusion of foreign ions into BaTiO3 or by crystallization of grain boundary and triple-point liquid phases. It was deduced that the partial pressure of oxygen in the sintering atmosphere influenced the microstructures, dopant distributions, and core–shell ratios of the grains in these materials. 相似文献
36.
This study examined the roles of speech perception and phonological processing in reading and spelling acquisition for native and nonnative speakers of English in the 1st grade. The performance of 50 children (23 native English speakers and 27 native Korean speakers) was examined on tasks assessing reading and spelling, phonological processing, speech perception, and receptive vocabulary at the start and end of the school year. Korean-speaking children outperformed native English speakers on each of the literacy measures at the start and end of 1st grade, despite differences in their initial phonological representations and processing skills. Furthermore, speech perception and phonological processing were important contributors to early literacy skills, independent of oral language skills, for children from both language groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
37.
Henkel Linda A.; Johnson Marcia K.; De Leonardis Doreen M. 《Canadian Metallurgical Quarterly》1998,127(3):251
This study shows that relative to younger adults, older adults are more adversely influenced by similar items when judging a memory's source, and the phenomenal features of their correctly and incorrectly attributed memories have greater overlap. The authors argue in accordance with the source monitoring framework that this age-related impairment in source accuracy is related to processes involved in binding features into complex memories and those involved in accessing and evaluating contextual features of memories. These processes are linked to medial temporal and frontal brain regions, respectively, as evidenced by correlations in older adults between source accuracy and neuropsychological tests often used to assess medial temporal and frontal function. The results suggest that adequate feature binding is particularly important when items from different sources share similar features and access-evaluation processes are particularly important after a delay. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
38.
Tested the hypothesis that certain personality styles may function as vulnerability factors leading to depression in the face of specific life event types. 10 dependent remitted depressed patients (aged 28–70 yrs) and 16 self-critical remitted depressed patients (aged 22–53 yrs) were followed for 6 mo and assessed for the occurrence of category-specific life events and level of depression, including clinical relapse. For dependent Ss only, congruency with life event content was associated both with self-reported levels of depression and with clinical relapse. Relapse for self-critical Ss was not differentially affected by the number of interpersonal or achievement life events experienced; however, dependent Ss relapsed more often after the experience of interpersonal rather than achievement events. No differences were reported between the total number of achievement stressors experienced by each subtype group, ruling out selective exposure as a possible explanation for these findings. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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