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21.
The effect of a prior gist-based versus item-specific retrieval orientation on recognition of objects and words was examined. Prior item-specific retrieval increased item-specific recognition of episodically related but not previously tested objects relative to both conceptual- and perceptual-gist retrieval. An item-specific retrieval advantage also was found when the stimuli were words (synonyms) rather than objects but not when participants overtly named objects during gist-based recognition testing, which suggests that they did not always label objects under general gist-retrieval instructions. Unlike verbal overshadowing, labeling objects during recognition attenuated (but did not eliminate) test- and interference-related forgetting. A full understanding of how retrieval affects subsequent memory, even for events or facts that are not themselves retrieved, must take into account the specificity with which that retrieval occurs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
22.
A quasi-optical reflection cavity intended to be used as the resonant load of a submillimeter wavelength oscillator has been designed, constructed, and tested. The resonator consists of three elements in cascade: a high Q, high finesse folded Fabry-Perot resonator, a lower Q, low finesse Fabry-Perot resonator, and a Littrow mounted diffraction grating. The resonator exhibits a Q of 6600 and 2.5 dB of loss at 63 GHz. The design can be scaled to 1 THz, where waveguide structures become impractical, to serve as the resonator for high frequency quantum well resonant tunneling device oscillators.  相似文献   
23.
As widely acknowledged, 40–50% of all melanoma patients harbour an activating BRAF mutation (mostly BRAF V600E). The identification of the RAS–RAF–MEK–ERK (MAP kinase) signalling pathway and its targeting has represented a valuable milestone for the advanced and, more recently, for the completely resected stage III and IV melanoma therapy management. However, despite progress in BRAF-mutant melanoma treatment, the two different approaches approved so far for metastatic disease, immunotherapy and BRAF+MEK inhibitors, allow a 5-year survival of no more than 60%, and most patients relapse during treatment due to acquired mechanisms of resistance. Deep insight into BRAF gene biology is fundamental to describe the acquired resistance mechanisms (primary and secondary) and to understand the molecular pathways that are now being investigated in preclinical and clinical studies with the aim of improving outcomes in BRAF-mutant patients.  相似文献   
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The effect of trap design, trap color, and a mixture of isothiocyanates on the capture of Ceutorhynchus assimilis (Paykull) was studied in a series of field experiments. Unbaited yellow water traps, a yellow sticky box trap, and a yellow sticky card trap, mounted vertically, or at 45° to the vertical with the yellow card facing upwards were effective for capturing seed weevils, but a horizontal yellow sticky card trap caught few. White, green, and black traps were unattractive. During migratory periods, trap catch could be enhanced two to four times with a lure consisting of a mixture of allyl, 3-butenyl, 4-pentenyl, and 2-phenylethyl isothiocyanates, but this bait did not attract in a trap with ineffective design. The sticky card trap, mounted at 45° to the vertical and baited with the isothiocyanate mixture, may be useful for monitoring movement of C. assimilis during migratory periods. However, during the colonization phase, lures of either a mixture of isothiocyanates or of allyl isothiocyanate alone were not attractive.  相似文献   
26.
Mobil Zeolite Catalysts for Monomers   总被引:1,自引:0,他引:1  
It has been about 20 years since Plank, Rosinski, and Hawthorne reported their spectacular results with metal-modified zeolite cracking catalysts for more efficient production of gasoline [1]. This discovery has saved an estimated 200 million barrels of crude oil each year in the United States alone [2]. In 1972, a patent by Argauer and Landolt described the preparation of a member of a generation of new synthetic zeolites, called ZSM- 5. It was unique because of its high silica/alumina ratio and greatly reduced coking rates for reactions with hydrocarbons by comparison with known low silica zeolites [3]. This material was an early member of a series of over 50 synthetic zeolitic substances prepared in Mobil laboratories.  相似文献   
27.
During germination of seeds of the gymnosperm,Pinus pinea, radioactivity from [2-14C]-mevalonate proceeded principally through the anaerobic reactions leading to squalene in the first 24 hr in both the haploid endosperm and the diploid embryo, and only with succeeding time (3–9 days) in both cases was label transferred to sterols in oxygen-requiring steps. The rates of turnover must be real and independent in the two tissues, since no consequential interchange of labelled lipids occurred between the endosperm and the embryo. Similar delayed conversion of squalene to sterols has been observed previously during germination of seeds of the angiosperm,Pisum sativum.  相似文献   
28.
Virtual Reality - This research report describes the development of a virtual reality (VR) laboratory stressor to study the effects of exposure to stressful events. The aim of the research was to...  相似文献   
29.
The process of distributed engineering design calls for a methodology making use of the most recent advances in optimization-based design including multidisciplinary and multiobjective optimization. In distributed design, the participating teams do not have access to the design problems of other teams but may exchange limited information about their own current designs, making negotiation among themselves a key mechanism to reach a desired compromise which, nevertheless, is also a Pareto design to the original problem. A mathematical model of this distributed but decomposable design process is posed and solved using Lagrangian relaxation, while Pareto optimality is equivalently converted to single-objective optimality by means of multicriteria decision making strategies. The proposed coordination algorithm allows negotiation among the teams (subproblems) by sharing only limited information that is restricted to values of optimization quantities. The proposed modeling and solution scheme is applied to a numerical example representing the design of vehicle subsystems and components.  相似文献   
30.
Web-scale discovery systems, such as Serial Solutions’ Summon? Service, are replacing older federated search technologies as the tool for users to access library resources quickly and easily. The impact of Web-scale discovery systems on instruction is not known. This study of instruction librarian perceptions of Summon's impact on instruction and student information literacy skills is based on a survey. The survey reveals librarians’ ambivalence toward Summon. While some librarians agree that Summon has the potential to change the way librarians teach information literacy skills, it has not been fully integrated into the classroom.  相似文献   
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