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991.
Lubell S 《Architectural record》2008,(8):120-123
HOK adds seamlessly to a 1962 Edward Durell Stone hospital on the Pacific coast, enhancing the original buildings's connection to nature. 相似文献
992.
Rapid pivot feeding in pipefish: flow effects on prey and evaluation of simple dynamic modelling via computational fluid dynamics 下载免费PDF全文
Most theoretical models of unsteady aquatic movement in organisms assume that including steady-state drag force and added mass approximates the hydrodynamic force exerted on an organism''s body. However, animals often perform explosively quick movements where high accelerations are realized in a few milliseconds and are followed closely by rapid decelerations. For such highly unsteady movements, the accuracy of this modelling approach may be limited. This type of movement can be found during pivot feeding in pipefish that abruptly rotate their head and snout towards prey. We used computational fluid dynamics (CFD) to validate a simple analytical model of cranial rotation in pipefish. CFD simulations also allowed us to assess prey displacement by head rotation. CFD showed that the analytical model accurately calculates the forces exerted on the pipefish. Although the initial phase of acceleration changes the flow patterns during the subsequent deceleration phase, the accuracy of the analytical model was not reduced during this deceleration phase. Our analysis also showed that prey are left approximately stationary despite the quickly approaching pipefish snout. This suggests that pivot-feeding fish need little or no suction to compensate for the effects of the flow induced by cranial rotation. 相似文献
993.
Jonas Eva; Martens Andy; Niesta Kayser Daniela; Fritsche Immo; Sullivan Daniel; Greenberg Jeff 《Canadian Metallurgical Quarterly》2008,95(6):1239
Research on terror-management theory has shown that after mortality salience (MS) people attempt to live up to cultural values. But cultures often value very different and sometimes even contradictory standards, leading to difficulties in predicting behavior as a consequence of terror-management needs. The authors report 4 studies to demonstrate that the effect of MS on people's social judgments depends on the salience of norms. In Study 1, making salient opposite norms (prosocial vs. proself) led to reactions consistent with the activated norms following MS compared with the control condition. Study 2 showed that, in combination with a pacifism prime, MS increased pacifistic attitudes. In Study 3, making salient a conservatism/security prime led people to recommend harsher bonds for an illegal prostitute when they were reminded of death, whereas a benevolence prime counteracted this effect. In Study 4 a help prime, combined with MS, increased people's helpfulness. Discussion focuses briefly on how these findings inform both terror-management theory and the focus theory of normative conduct. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
Cox Cathy R.; Arndt Jamie; Pyszczynski Tom; Greenberg Jeff; Abdollahi Abdolhossein; Solomon Sheldon 《Canadian Metallurgical Quarterly》2008,94(4):696
Six studies examined the role of young adults' parental attachment in terror management. Studies 1-3 revealed that activating thoughts of one's parent in response to mortality salience (MS) reduced death-thought accessibility and worldview defense and increased feelings of self-worth. Studies 4-5 demonstrated that MS led to greater ease of recalling positive maternal interactions and greater difficulty recalling negative interactions, and increased attraction to a stranger who was described as being similar to one's parent. If reliance on parents for terror management purposes reflects the operation of attachment mechanisms, then such effects should vary on the basis of an individual's attachment style. Study 6 demonstrated that, after MS, insecure individuals were more likely to rely on relationships with their parents, whereas secure individuals were more likely to rely on relationships with romantic partners. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Nanocomposites of titanium dioxide (TiO(2)) and multi-walled carbon nanotubes (MWNTs) were prepared and deposited by sol-gel spin coating on borosilicate substrates and sintered in air at 300?°C for 15?min. Further irradiation of the films with different CO(2) laser intensities (4.3-17?W?m(-2)) was carried out in order to crystallize TiO(2) in the anatase form while preserving the MWNT's structure. The laser irradiation changed the crystal structure of the coatings and also affected the wettability and photocatalytic activity of the films. The anatase phase was only observed when a minimum laser intensity of 12.5?W?m(-2) was used. The contact angle decreased with the enhancement of the laser intensity. The photocatalytic activity of the films was determined from the degradation of a stearic acid layer deposited on the films. It was observed that the addition of carbon nanotubes themselves increases the photocatalytic activity of TiO(2) films. This efficiency is even improved when high CO(2) laser intensities are used during the sintering of the coatings. 相似文献
996.
Nanoscale materials have increasingly become subject to intense investigation for use in cancer diagnosis and therapy. However, there is a fundamental dearth in cellular-level understanding of how nanoparticles interact within the tumor environment in living subjects. Adopting quantum dots (qdots) for their excellent brightness, photostability, monodispersity, and fluorescent yield, we link arginine-glycine-aspartic acid (RGD) peptides to target qdots specifically to newly formed/forming blood vessels expressing alpha vbeta 3 integrins. Using this model nanoparticle system, we exploit intravital microscopy with subcellular ( approximately 0.5 microm) resolution to directly observe and record, for the first time, the binding of nanoparticle conjugates to tumor blood vessels in living subjects. This generalizable method enabled us to show that in this model qdots do not extravasate and, unexpectedly, that they only bind as aggregates rather than individually. This level of understanding is critical on the path toward ensuring regulatory approval of nanoparticles in humans for disease diagnostics and therapeutics. Equally vital, the work provides a platform by which to design and optimize molecularly targeted nanoparticles including quantum dots for applications in living subjects. 相似文献
997.
Germain M Fraundorf P Lin S Guliants EA Bunker CE Buckner SW 《Journal of nanoscience and nanotechnology》2008,8(3):1481-1488
We describe the synthesis and characterization of srilankite (Ti2ZrO6) nanowires. The nanowires are produced via hydrothermal synthesis with a TiO2/ZrO2 mixture under alkaline conditions. The zirconium titanate nanowires have median diameters of 60 nm and median lengths of 800 nm with the (022) axis along the length of the nanowire. Electron microscopy, energy dispersive X-ray spectroscopy, powder X-ray diffraction, and electron diffraction are used to characterize the phases and compare nanowires produced with varying molar ratios of Ti and Zr. Electron diffraction patterns produced from single nanowires show highly crystalline nanowires displaying a compositional-ordering superlattice structure with Zr concentrated in bands within the crystal structure. This is in contrast to naturally occurring bulk srilankite where Zr and Ti are randomly substituted within the crystal lattice. Streaking is observed in the electron diffraction patterns suggesting short-range ordering within the superlattice structure. 相似文献
998.
Li Y Zhang S Sritharan T Li X Liu Y Chen TP 《Journal of nanoscience and nanotechnology》2008,8(5):2618-2622
SrBi2Ta2O9 (SBT) is a bismuth layered perovskite with attractive ferroelectric properties for random access memory applications. Our previous studies showed that Nd-doped SBT (SNBT) thin films exhibited an improved remnant polarization and reduced coercivity. This paper concentrates on the effect of Ta nanobarrier in between the SNBT and the Pt layers. Without the nanobarrier, severe bismuth diffusion is revealed by the secondary ion mass spectroscopy. However, with a nano layer (up to 2 nm) of Ta metal, the interfacial diffusion is effectively suppressed even at 800 degrees C. Details of the composition profiling, film crystallinity and remnant polarization are discussed in view of the nanobarrier thickness. 相似文献
999.
Kevin Greenberg Robert Zheng Michael Gardner Matthew Orr 《Journal of Computer Assisted Learning》2021,37(3):735-744
The cognitive theory of multimedia learning postulates learning information in a dual-modality design is more effective than in a single modality, which is known as the modality effect. Research has found that the modality effect supports problem-solving learning, but not retention-based learning. This divergence in findings can be explained by the mediating effects of individual differences in visuospatial working memory. The current study confirmed the modality effect, showing superiority of dual-modality over single modality. Results revealed a significant interaction between visuospatial working memory and modality by retention, but no such interaction was obtained for problem solving. It was found that learners with low visuospatial working memory scored higher on retention in dual modality than these in single modality. Interestingly, no differences were found for learners with high visuospatial working memory on retention in both single- and dual-modality conditions. The findings may explain for whom the modality effect works in relation to retention. Finally, the analysis showed no association between modality conditions and subtypes of cognitive load, that is, extraneous and germane cognitive load. 相似文献
1000.