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11.
Rice Catherine; Koinis Daphne; Sullivan Kate; Tager-Flusberg Helen; Winner Ellen 《Canadian Metallurgical Quarterly》1997,33(1):54
68 3-yr-olds received a standard appearance–reality task along with either a trick task, in which the appearance question was placed in the context of a deceptive game, or a reduced information processing task, in which a dual object (e.g., a sponge-rock) was presented along with an object that matched the dual object's identity (a sponge) and one that matched the dual object's appearance (a rock). Children were more likely to pass either the trick or reduced information processing task and fail the standard than the reverse. Thus, 3-yr-olds can grasp the distinction between appearance and reality (a) when their goal is to trick someone, which may prime them to think about the other's mental state, and (b) when they do not need to hold conflicting object identities in mind at the same time. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
12.
The hippocampus, objects, and their contexts. 总被引:1,自引:0,他引:1
Rats with hippocampal aspiration lesions and controls were trained on delayed nonmatching to sample with small complex goal boxes, presented trial uniquely. A series of experiments then used pairs of large or small boxes, presented repeatedly. The lesions impaired choice accuracy when the rats were tested with large empty boxes but not when small boxes containing 3-dimensional objects were used. There was a comparable impairment when the rats were tested with pairs of large complex boxes, which contained arrays of objects, identical to those used in the smaller boxes but necessarily spaced further apart. Subsequent experiments revealed that the lesion deficit with large boxes was reduced by insertion of a continuous line of distinctive objects and eliminated by trial-unique presentation of large boxes. The results are discussed in terms of (non) spatial accounts of hippocampal function and the compensatory effects of novel object cues. We conclude that, for hippocampal rats, spatial cues, although useless, can nonetheless be profoundly disruptive. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
13.
According to J. F. Dovidio and S. L. Gaertner's (1998) integrated model of racism, politically liberal European Americans tend to express racism differently than conservative European Americans, with liberals demonstrating aversive racism and conservatives, symbolic or modern racism. In support of the model, in Experiment 1 liberals showed bias in favor of a twice-prosecuted African American relative to a European American in their judgment of double jeopardy, whereas conservatives did the reverse. Experiment 2 replicated these effects while eliminating a confound in the design of Experiment 1. Experiment 3 found evidence for the intrapsychic conflict hypothesized to underlie aversive racism. Specifically, only liberals displayed greater physiological arousal to the touch of an African American versus a European American experimenter. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
14.
Charles A. Bateman Lijie Zhang Helen M. Chan Martin P. Harmer 《Journal of the American Ceramic Society》1992,75(5):1281-1283
It is experimentally observed that the peritectic reaction, 211 + liquid → 123, can be driven essentially to completion in 1 h at an undercooling of only ∽30°C. The kinetic data, together with the observed microstructures, are inconsistent with the normal mechanism of the peritectic reaction. It is proposed that the mechanism of the reaction involves dissolution of 211 particles into the liquid and precipitation of solid 123. The aligned grain structure is explained through sympathetic nucleation of new 123 grains on existing grains. 相似文献
15.
David A. J. Moran Helen McLelland Khaled Elgaid Griogair Whyte Colin R. Stanley Iain Thayne 《Electron Devices, IEEE Transactions on》2006,53(12):2920-2925
Continued research into the development of III-V high-electron mobility transistors (HEMTs), specifically the minimization of the device gate length, has yielded the fastest performance reported for any three terminal devices to date. In addition, more recent research has begun to focus on reducing the parasitic device elements such as access resistance and gate fringing capacitance, which become crucial for short gate length device performance maximization. Adopting a self-aligned T-gate architecture is one method used to reduce parasitic device access resistance, but at the cost of increasing parasitic gate fringing capacitances. As the device gate length is then reduced, the benefits of the self-aligned gate process come into question, as at these ultrashort-gate dimensions, the magnitude of the static fringing capacitances will have a greater impact on performance. To better understand the influence of these issues on the dc and RF performance of short gate length InP pHEMTs, the authors present a comparison between In0.7Ga0.3As channel 50-nm self-aligned and "standard" T-gate devices. Figures of merit for these devices include transconductance greater than 1.9 S/mm, drive current in the range 1.4 A/mm, and fT up to 490 GHz. Simulation of the parasitic capacitances associated with the self-aligned gate structure then leads a discussion concerning the realistic benefits of incorporating the self-aligned gate process into a sub-50-nm HEMT system 相似文献
16.
Narendra B. Dahotre T. Dwayne McCay Mary Helen McCay 《Materials and Manufacturing Processes》1994,9(3):447-466
A Laser Induced Liquid Phase Reaction Synthesis Assisted Joining technique is employed for SiC-particulate/Al-alloy composite to produce joints. Joints in SiC/Al-alloy composite are produced by synthesis of suitable material product as a result of interaction between composite and Ti (or Ti-alloy) reactive filler material induced by laser energy in the joint region. Such reaction product minimizes or eliminates the formation of deleterious aluminum carbide phase in the joint region depending upon the type and nature of die interfacial reactive filler material and also the laser processing parameters. A laser beam is utilized to both synthesize the interfacial reactant mixture and to heat the base material adjacent to the joint region to minimize the thermal stresses. The technique along with suitable filler material, further can be extended to a variety of metal matrix composite systems including combinations of Gr/Al, B/Al, B4C/Mg, Steel/Al, W/Al, Al2 O3 and Gr/Cu which are excellent for use in various automotive, aerospace and electronic applications. Preliminary observations describing the proof of concept of laser induced reaction joining of metal matrix composites are reported 相似文献
17.
A series of experiments introduced interruptions to the execution phase of simple Tower of London problems and found that the opportunity for preparation before the break in task reduced the time cost at resumption. Retrieval of the suspended goal was facilitated when participants were given the opportunity to encode retrieval cues during an "interruption lag" (the brief time before engaging in the interrupting task) but was impeded when these visual cues were subsequently altered following interruption. The results provide useful support for the goal-activation model (E. M. Altmann & G. J. Trafton, 2002), which assumes that context--at the points of both goal suspension and goal retrieval--is critical to efficient interruption recovery. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
18.
Lisa Goedtke Heike Sprenger Ute Hofmann Felix F. Schmidt Helen S. Hammer Ulrich M. Zanger Oliver Poetz Albrecht Seidel Albert Braeuning Stefanie Hessel-Pras 《International journal of molecular sciences》2021,22(1)
Polycyclic aromatic hydrocarbons (PAHs) are environmental pollutants produced by incomplete combustion of organic matter. They induce their own metabolism by upregulating xenobiotic-metabolizing enzymes such as cytochrome P450 monooxygenase 1A1 (CYP1A1) by activating the aryl hydrocarbon receptor (AHR). However, previous studies showed that individual PAHs may also interact with the constitutive androstane receptor (CAR). Here, we studied ten PAHs, different in carcinogenicity classification, for their potential to activate AHR- and CAR-dependent luciferase reporter genes in human liver cells. The majority of investigated PAHs activated AHR, while non-carcinogenic PAHs tended to activate CAR. We further characterized gene expression, protein abundancies and activities of the AHR targets CYP1A1 and 1A2, and the CAR target CYP2B6 in human HepaRG hepatoma cells. Enzyme induction patterns strongly resembled the profiles obtained at the receptor level, with AHR-activating PAHs inducing CYP1A1/1A2 and CAR-activating PAHs inducing CYP2B6. In summary, this study provides evidence that beside well-known activation of AHR, some PAHs also activate CAR, followed by subsequent expression of respective target genes. Furthermore, we found that an increased PAH ring number is associated with AHR activation as well as the induction of DNA double-strand breaks, whereas smaller PAHs activated CAR but showed no DNA-damaging potential. 相似文献
19.
Helen L. Ngo Alberto Nuñez Wenbin Lin Thomas A. Foglia 《European Journal of Lipid Science and Technology》2007,109(3):214-224
Branched‐chain (bc) saturated fatty acids (SFA) have potential as oleochemical intermediates since they have better oxidative stability than linear unsaturated fatty acids (UFA) and have better low‐temperature properties than linear SFA. Previous studies in converting UFA to bc‐FA using clay catalysts have resulted in only modest yields and conversions. Recent reports, however, have suggested that certain zeolites can be effective catalysts for converting UFA to bc‐FA in higher yields and conversions. In this work, we examined the scope and potential of the zeolite‐catalyzed synthesis of bc‐FA starting from readily available monounsaturated linear FA. Our results show that common UFA such as oleic acid can be converted to bc‐isomers using modified Ferrierite zeolite catalysts with high conversions (98%) and high selectivity (85%) and that the zeolite catalysts are reusable for at least three cycles. The positions of branching (methyl) on the FA chain were determined from the GC‐MS spectra of the picolinyl esters of the bc‐FA. 相似文献
20.
Fanbo Meng Zhiyong Wu Jia Jia Helen Meng Lianhong Cai 《Multimedia Tools and Applications》2014,73(1):463-489
Emphasis plays an important role in expressive speech synthesis in highlighting the focus of an utterance to draw the attention of the listener. We present a hidden Markov model (HMM)-based emphatic speech synthesis model. The ultimate objective is to synthesize corrective feedback in a computer-aided pronunciation training (CAPT) system. We first analyze contrastive (neutral versus emphatic) speech recording. The changes of the acoustic features of emphasis at different prosody locations and the local prominences of emphasis are analyzed. Based on the analysis, we develop a perturbation model that predicts the changes of the acoustic features from neutral to emphatic speech with high accuracy. Further based on the perturbation model we develop an HMM-based emphatic speech synthesis model. Different from the previous work, the HMM model is trained with neutral corpus, but the context features and additional acoustic-feature-related features are used during the growing of the decision tree. Then the output of the perturbation model can be used to supervise the HMM model to synthesize emphatic speeches instead of applying the perturbation model at the backend of a neutral speech synthesis model directly. In this way, the demand of emphasis corpus is reduced and the speech quality decreased by speech modification algorithm is avoided. The experiments indicate that the proposed emphatic speech synthesis model improves the emphasis quality of synthesized speech while keeping a high degree of the naturalness. 相似文献