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AbstractThe demand for structural logs in wooden construction is substantial. However, logs, due to their inherent structural characteristics, are prone to developing checks during drying process. Kerf treatment is a practical and effective pretreatment technology for drying that can significantly reduce checking. Nonetheless, the optimal location for the kerf treatment remains unexplored. This study was designed to position the kerf based on the location of the pith and assessed the effects of single kerf, double kerf, and kerf-center boring treatments on log drying quality. The check ratio of kerf logs decreased significantly (p < 0.05). As kerf depth increased, the check ratio slightly decreased, while the moisture content (MC) difference between the core layer and surface layer increased. Additionally, the inclusion of kerfs in counterpoint positions exhibited a profound effect on reducing the check ratio. Eccentricity influenced the later drying stages of the logs. The check ratio of non-eccentricity logs tended to stabilize during the later drying period, while that of eccentric logs continued to increase. For eccentric logs, this study employed the counterpoint double-kerf process, resulting in a surface check ratio of 0.42%. For non-eccentric logs, utilizing a single shallow kerf significantly improved the surface drying quality, with a surface check ratio of 1.00%. [ABSTRACT FROM AUTHOR]

Titania nanotube (NT) arrays have been widely used as cell‐supporting matrices. However, cells are always seeded on the porous surface of the NT array and have very limited interactions with each individual NT in the array. In this study, titania hollow microtubes (HMTs) were synthesized via a gelatin‐template sol‐gel route and then utilized as free‐standing cell‐supporting matrices for the first time. The resultant titania HMTs were studied by field emission scanning electron microscopy, energy‐dispersed spectroscopy, X‐ray diffraction, and Fourier‐transform infrared spectroscopy. Each HMT was composed of rutile‐type titania nanoparticles with diameters of 50–100 nm and a diameter of 50–100 µm. The results from a leaching liquor assay demonstrated good biocompatibility of titania HMTs. Each HMT has been demonstrated to independently support the adhesion and proliferation of osteoblast MC3T3‐E1 cells. For comparison, titania NT arrays, not independent titania NT, only supported the adhesion of cells on their porous surface. Thus, the resultant titania HMTs are applicable to free‐standing and biocompatible cell‐supporting matrices. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of growth ring width, height from the tree base, and loading direction on the transverse compressive strength of Japanese larch wood, which is commonly used in wood structures in China. Plantation wood is often used to replace natural forest woods for reconstruction purposes, despite significant differences in properties (e.g., growth rings, density, strength) between them. The ends of transversely compressed wood members in such structures are prone to damage by breaking or crushing. A transverse compressive test was conducted following Chinese national standards, which revealed the following key findings. (1) There was a significant difference in the transverse compressive strength of wood with different growth ring widths (p < 0.05). The radial and slant compressive strength of wood increases with growth ring width, while the tangential compressive strength decreases as growth ring width increases. (2) The transverse compressive strength of wood decreases as the height from the tree base increases. The radial, tangential, and slant compressive strength at a lower height were 18.39%, 22.58%, and 18% higher than those at a greater height in the stem, respectively, with significant differences at the 0.05 level. (3) The load–displacement curve of Japanese larch wood under radial and slant compression follows a "three-segment" form. In contrast, the load–displacement curve of tangential compression is a continuous curve that drops sharply upon reaching its highest point. (4) There is a significant difference in the transverse compressive strength of Japanese larch wood in different loading directions when growth ring width and height from the tree base are constant (p < 0.05), which fall into order as tangential > radial > slant. [ABSTRACT FROM AUTHOR]

Estimating 3D hand shape from a single-view RGB image is important for many applications. However, the diversity of hand shapes and postures, depth ambiguity, and occlusion may result in pose errors and noisy hand meshes. Making full use of 2D cues such as 2D pose can effectively improve the quality of 3D human hand shape estimation. In this paper, we use 2D joint heatmaps to obtain spatial details for robust pose estimation. We also introduce a depth-independent 2D mesh to avoid depth ambiguity in mesh regression for efficient hand-image alignment. Our method has four cascaded stages: 2D cue extraction, pose feature encoding, initial reconstruction, and reconstruction refinement. Specifically, we first encode the image to determine semantic features during 2D cue extraction; this is also used to predict hand joints and for segmentation. Then, during the pose feature encoding stage, we use a hand joints encoder to learn spatial information from the joint heatmaps. Next, a coarse 3D hand mesh and 2D mesh are obtained in the initial reconstruction step; a mesh squeeze-and-excitation block is used to fuse different hand features to enhance perception of 3D hand structures. Finally, a global mesh refinement stage learns non-local relations between vertices of the hand mesh from the predicted 2D mesh, to predict an offset hand mesh to fine-tune the reconstruction results. Quantitative and qualitative results on the FreiHAND benchmark dataset demonstrate that our approach achieves state-of-the-art performance. [ABSTRACT FROM AUTHOR]