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1.
The frequent evocative comparisons between music and architecture in the text of the Modulor may explain why Le Corbusier, in this constant search for ordering principles, considered his proportional sequence to be equivalent to a musical scale. Yet, since the dimensional ratios of Le Corbusier’s ‘scale’ are much larger than the pitch ratios of the latter, the Modulor comes much closer to another structural element of music, that of harmony. By adjusting the Modulor ratios to the corresponding ratios of musical chords, three variants of a “musical” Modulor can be generated – Chromatic, Major and Minor. If, in addition, the two sets of the malebased Modulor dimensions are replaced with a universal female-male set, the inherently complex Modulor numbers become simpler and clear. The Master’s intention of producing a rational and practical system of proportions, which is related to both the scale of the human being, and to the order inherent in the physical nature of sound, can thus be realized.  相似文献   
2.
We adapt the technology acceptance model (TAM) to examine the factors influencing mobile gaming adoption among “global youth.” Our model replaces usefulness with convenience, incorporating visual appeal and escapism as antecedents of fun, and perceived novelty and economic value as antecedents of convenience. Questionnaire surveys were conducted in the U.S., Spain, and the Czech Republic, producing 432 usable responses. In the structural model assessment with the pooled sample, convenience exercises greater effects on attitude toward mobile games than fun, suggesting that the most important driver is probably the capability of being used flexibly at any time and in any place, rather than mere enjoyment. Tests of latent means suggest that most dimensions are perceived more strongly in the Czech Republic.  相似文献   
3.

Thermal stability, mechanism, and kinetics of thermally induced microstructural transformations and their effects on magnetic permeability of Fe72Si15B8V4Cu1 alloy with combined amorphous/nanocrystalline structure were studied. DTA curves revealed two separated thermally activated exothermic events in the temperature ranges from 740 K to 820 K (467 °C to 547 °C) and 870 K to 930 K (597 °C to 657 °C). Crystalline phases present in the as-prepared and thermally treated alloy samples were identified, and their microstructural parameters were determined using XRD, while, to gain further insight into the mechanism of microstructural transformations, AFM and SEM–EDS analyses were performed. Deconvolution of the complex DTA peak into individual steps was conducted, and, in correlation with the results of microstructural analysis, kinetic triplets corresponding to individual transformation steps were determined, allowing for the estimation of the lifetimes of the alloy at different temperatures. Magnetic permeability measurements showed that, in spite of the influence of microstructural transformations on magnetic properties of the alloy, the favorable magnetic properties are retained over relatively a wide temperature range.

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5.
Remarkably, a number of definitive epithelia, such as that of the anterior lens, give rise when suspended within 3D gels of type I collagen, to elongate, bipolar shaped cells that exhibit the ultrastructure, polarity, and migratory ability of mesenchymal cells. They begin producing type I collagen and stop producing crystallins, type IV collagen, and laminin. Here, we investigated changes in beta 1 integrins and their extracellular matrix (ECM) ligands during this transdifferentiation. The former free surface of the lens epithelium that is now in contact with collagen begins within a day to stain intensely for beta 1 and it is this surface rather than the surface facing the basement membrane that gives rise to mesenchymal cells. Immunoprecipitation experiments reveal a large increase in the beta 1 integrin subunit on mesenchymal cells as compared to the epithelium of origin. The alpha 5 integrin subunit, which is barely detectable in the lens, increases in the mesenchymal cells and alpha 3 continues to be expressed at about the same level as in the epithelium. alpha 6, the epithelial integrin subunit, and laminin, its ECM ligand, are not detected immunohistochemically or biochemically in the mesenchyme. Rather, the mesenchymal cells secrete abundant fibronectin, the major ECM ligand for alpha 5 beta 1. RGD peptides do not inhibit the transformation but antibodies to beta 1 do perturb the emigration of mesenchymal cells from the lens apical surface. We conclude that the beta 1 integrins newly expressed on the apical epithelial surface interact with the surrounding 3D collagen gel to help bring about this unusual epithelial-mesenchymal transition.  相似文献   
6.
The effects of ion implantation and subsequent annealing on the surface morphology of thin amorphous chalcogenide films of the As-Se system have been studied. Ion implantation of nitrogen (N+) with an energy E=100 keV and high doses (typically D=1.1016 cm−2) has been carried out at room temperature. Subsequent thermal annealing treatments near the melting temperature (Tg∼160°C) have been performed leading to changes in the thin-film morphology, which are dependent on the As content and are best expressed for the As3Se2 films. Optical microscope photographs reveal details of the rippled surface exhibiting quasi-regular domain-like structure. The parameter λ, describing it, is dependent on the film thickness and grows with its increase. Thermal annealing near Tg also influences the diffuse optical reflectivity—it increases considerably while the interference features tend to disappear with the appearance of the rippled film surface structure and the effect is again greater for the thicker films.  相似文献   
7.
WC–Co cemented carbide has been investigated using instrumented indentation with maximum applied loads from 0.1 to 10 mN. The hardness and indentation modulus of individual phases and the influence of crystallographic orientation of WC on the hardness and indentation modulus have been studied. The hardness of the Co binder was approximately 10 GPa and that of WC grains up to 50 GPa with relatively large scatter under the indentation load of 1 mN. Investigation of the role of crystallographic orientation of WC grains on hardness at 10 mN load revealed average values of HITbasal = 40.4 GPa (EITbasal = 674 GPa) and HITprismatic = 32.8 GPa (EItprismatic = 542 GPa), respectively. The scatter in the measured values at low indentation loads is caused by the effects of surface and sub-surface characteristics (residual stress, damaged region) and at higher loads by “mix-phase” volume below the indenter.  相似文献   
8.
Sex differences in parasite infections: patterns and processes   总被引:1,自引:0,他引:1  
Sex differences in parasite infection rates, intensities, or population patterns are common in a wide range of taxa. These differences are usually attributed to 1 of 2 causes: (1) ecological (sociological in humans); and (2) physiological, usually hormonal in origin. Examples of the first cause include differential exposure to pathogens because of sex-specific behavior or morphology. The second cause may stem from the well-documented association between testosterone and the immune system; sexually mature male vertebrates are often more susceptible to infection and carry higher parasite burdens in the field. Although many researchers favor one explanation over the other, the requisite controlled experiments to rule out confounding variables are often neglected. We suggest that sex differences in disease have evolved just as sex differences in morphology and behavior, and are the result of selection acting differently on males and females. Research has often focused on proximate mechanistic explanations for the sex difference in infection rates, but it is equally important to understand the generality of the patterns in an evolutionary context. Because males potentially gain more than females by taking risks and engaging in competition, sexual selection pressure has shaped male behavior and appearance to maximize competitive ability and attractiveness. Many of the classic male attributes such as antlers on deer are testosterone-dependent, putting males in what appears to be a cruel bind: become vulnerable to disease by developing an attractive secondary sexual ornament, or risk lowered mating success by reducing it. A variety of hypotheses have been put forward to explain why males have not circumvented this dilemma. The mating system of the host species will influence the likelihood of sex differences in parasite infection, because males in monogamous species are subject to weaker sexual selection than males in polygynous species. Whether these evolutionary generalizations apply to invertebrates, which lack testosterone, remains to be seen.  相似文献   
9.
Pulsating potential electrolysis has been applied to one typical electrocatalytic reaction ie, the oxidation of formic acid on platinum and platinum partially covered by lead adatoms electrodes. It has been found that much higher average cds can be obtained with such regimes than in constant potential electrolysis. The effect can be of considerable interest for the application in electrochemical power sources. An analysis of the mechanism of effects of pulsating potentials has been given. A calculated frequency dependence of the average current density is in agreement with experimental one for both electrodes.  相似文献   
10.
This note discusses the effects of the electrode position scaling on the realistic Laplacian (RL) computation. It is shown that when the RL is estimated with the help of Tikhonov regularization and the generalized cross-validation (GCV) criterion, improper electrode position scaling may influence the GCV criterion, which results in the decrease of RL precision. We identify what the proper scaling should be, and we provide a closer examination of how the GCV criterion is affected by the electrode position scaling.   相似文献   
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