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Herein, orderly arranged bamboo-like mesoporous silica materials were prepared using cetyltrimethylammonium bromide (CTAB) as the template and n-hexanol as the long-chain alcohol cosurfactant. The ordered meso-structure was characterized by XRD analysis, field emission scanning electron microscopy (FE-SEM, Hitachi S4800), transmission electron microscopy, BET and IR spectroscopy analysis. The effects of the CTAB/n-hexanol molar ratio(R), length of the hydrophobic chain with a terminating hydroxyl group on the long-chain alcohol cosurfactant, parity of the hydrophobic carbon atoms on the surface topography, specific surface area, and pore size of the powder were investigated. The results showed that when the molar ratio = 1, the mesoporous silica presented neatly arranged bamboo segment lengths of 19.6–23.9 μm, platycodon grandiflorum widths of 2.13–3.32 μm, pore size of 3.04 nm, and surface area of 820.034 m2/g. Increasing or decreasing the amount of n-hexanol directing led to denser or looser lateral molecular interactions between CTAB and the co-structure-directing agents that respectively reduced or increased the pore size, with the latter resulting in the formation of spherical particles. When n-hexanol was replaced by n-heptanol or n-octanol, the pore size and surface area of the mesoporous silica decreased significantly with the increase in the hydrophobic chain length. [ABSTRACT FROM AUTHOR]

Architects should consider the aesthetic experience of potential users when designing architectures. Previous studies have shown that subjective aesthetic judgment of architectures is influenced by structure features, and Western observers prefer structures that have curvilinear contours, high ceilings, and open space. The building styles, however, vary across cultures, and it remains unclear whether the preference for contours, ceiling height, and openness exist across cultures. To investigate this issue, this study analyzes the aesthetic judgment of Chinese observers, and the results demonstrate that Chinese observers also prefer high ceilings and open space. Preference for curvilinear contours, however, interacts with ceiling height and openness. Simple effect analysis reveals that Chinese observers prefer curvilinear contours only when the ceiling is low and the space is closed. In sum, these results suggest that preference for high ceilings and open space is robust for Chinese observers, but the preference for curvilinear contours is less reliable. [ABSTRACT FROM AUTHOR]

Understanding the factors influencing the aesthetic experience of architectures is an important topic in empirical aesthetics. In this study, we examined the effect of three architectural factors, i.e., ceiling height, openness, and contour, on viewers' aesthetic appreciation through a series of experiments. In previous studies on architectural aesthetics, participants were usually asked to view an image of an architectural space for a few seconds. The long viewing time allows them to focus on different parts of the architecture and then make an aesthetic judgment. The long viewing time, however, also makes it difficult to obtain viewers' aesthetic scores for a large number of architectural spaces in a short period. In this study, we shortened the visual presentation time to 200 ms, which allowed the viewers to have only one fixation on the image, and asked the viewers to make an aesthetic judgment. It was found that the experiment with a 200-ms viewing time could establish how the three architectural factors influenced aesthetic judgment as well as previous experiments with a 3,000-ms viewing time, suggesting that aesthetic judgment could be made within one fixation. Additionally, we investigated the impact of color on architectural aesthetic judgment by presenting grayscale images. We found that the three architectural factors influenced aesthetic judgment in similar ways for both color and grayscale images. In summary, we found that color was not a main factor modulating viewers' architectural aesthetic judgments, and we also presented a way to quickly obtain aesthetic scores for architectural spaces. [ABSTRACT FROM AUTHOR]

Due to their excellent properties, polymides (PIs) result promising as high-performance materials in different technological fields. In this research, both micron-sized tubular mesoporous silica (mSiO2) and double-tube tubular diatomite particles with cadmium sulfide quantum dots are prepared by chemical deposition method. A cluster of type fluorescent particles is prepared by self-assembling carbon quantum dots (CDs) on the inner surface of the above materials. Then, a fluorescent polyimide film is prepared by uniform dispersion of fluorescent particles. The study of different properties of the film becomes then mandatory to evaluate possible application perspectives. Therefore, after synthesizes, all samples were investigated in term of chemical structure, microstructure and fluorescence properties by infrared spectroscopy, X-ray diffraction, scanning electron microscopy and fluorescence spectrophotometry. Fluorescence performance of diatomite-based fluorescent particles (diatomite@CdS@CDs) results not as good as the mSiO2-based fluorescent particles (mSiO2@CdS@CDs) ones; the mechanical properties of the composite film deteriorate as the content of the inorganic component increases. The performance of PI/mSiO2@CdS@CDs is 7.6 times the PI/diatomite@CdS@CDs ones. [ABSTRACT FROM AUTHOR]

Ultrasonic is one of the well-known methods for surface roughness measurement, but small roughness will only lead to a subtle variation of transmission or reflection. To explore sensitive techniques for surfaces with small roughness, nonlinear ultrasonic measurement in through-transmission and pulse-echo modes was proposed and studied based on an effective unit-cell finite element (FE) model. Higher harmonic generation in solids was realized by applying the Murnaghan hyperelastic material model. This FE model was verified by comparing the absolute value of the nonlinearity parameter with the analytical solution. Then, random surfaces with different roughness values ranging from 0 μm to 200 μm were repeatedly generated and studied in the two modes. The through-transmission mode is very suitable to measure the surfaces with roughness as small as 3% of the wavelength. The pulse-echo mode is sensitive and effective to measure the surface roughness ranging from 0.78% to 5.47% of the wavelength. This study offers a potential nondestructive testing and monitoring method for the interfaces or inner surfaces of the in-service structures. [ABSTRACT FROM AUTHOR]

WHAMM, a member of the Wiskott-Aldrich syndrome protein (WASP) family, is an actin nucleation promoting factor (NPF) that also associates with membranes and microtubules. Here we report that WHAMM is required for autophagic lysosome reformation (ALR). WHAMM knockout causes impairment of autolysosome tubulation, which results in accumulation of enlarged autolysosomes during prolonged starvation. Mechanistically, WHAMM is recruited to the autolysosome membrane through its specific interaction with PI(4,5)P2. WHAMM then works as an NPF which promotes assembly of an actin scaffold on the surface of the autolysosome to promote autolysosome tubulation. Our study demonstrates an unexpected role of the actin scaffold in regulating autophagic lysosome reformation. After autophagic cargo degradation, autolysosomes undergo a reformation process to recycle lysosomal membrane components. Here, Dai et al. demonstrate that the actin nucleation promoting factor WHAMM is required for autolysosome reformation by providing an actin scaffold to drive tubulation. [ABSTRACT FROM AUTHOR]