Spatially resolved moisture content (MC) measurement is important for understanding moisture migration and improving drying control in wood. This study developed a CT-referenced end-to-end near-infrared hyperspectral imaging (NIR-HSI) framework for moisture content mapping in Japanese cypress (Chamaecyparis obtusa) during drying. X-ray CT images acquired at different moisture states were calibrated to density values and registered to corresponding oven-dry CT images. A latewood mask-based deformable registration method was introduced to compensate for drying-induced deformation, enabling voxel-wise MC calculation. The resulting CT-derived moisture maps were averaged along the thickness direction and screened for reliability, yielding 163 valid paired datasets for partial least squares (PLS) baseline and U-Net model development and evaluation. A conventional PLS regression model was established as a baseline, and a U-Net model was trained to directly predict MC maps from NIR-HSI data. The proposed CT registration method substantially improved image correspondence, increasing the mean Dice similarity coefficient of latewood masks from 0.536 to 0.964. The CT-derived mean MC showed excellent agreement with gravimetric measurements, with an R2 of 0.9958 and a root mean square error (RMSE) of 3.8729
Wood identification is an important aspect for understanding the historical and geographical background of ancient wooden materials. One of the major methods for wood identification is the anatomical inspection of its morphological data from a micrograph of the thin section or volumetric X-ray CT data, while another effective method is DNA (deoxyribonucleic acid) barcode analysis. This study aimed to establish a DNA barcode analysis protocol for aged softwoods. For this purpose, we performed a DNA barcode analysis using “authentic” samples deposited in xylarium. Two measures were implemented in this study: (i) polymerase chain reaction (PCR) amplification of a shorter marker region and (ii) physical separation of the rooms for DNA extraction and PCR amplification. Notably, the latter addressed the issue of inconsistent identification results across analyses. However, incorrect identification is sometimes obtained, indicating that further improvements to the protocol are still required. Nonetheless, this study advances the DNA barcode analysis protocol for wood identification by highlighting the need to eliminate external DNA contamination. In summary, our findings clarify the requirements for a reliable wood-identification protocol based on DNA barcodes and lay the foundation for a more robust procedure.
This study estimated the carbon stocks in Japan’s building stock till 2050, categorizing buildings according to use and number of stories and examining scenarios that promote wooden construction including non-residential and medium- to high-rise buildings. Previous projections have largely focused on residential buildings, and the influence of increased wooden construction in other building types has not been sufficiently evaluated. To address this, multiple future scenarios were developed based on projected floor area stock, including a conventional construction scenario and alternative scenarios that progressively expanded the range of buildings suitable for wooden construction. Carbon stocks were then estimated for each scenario. The results indicate that carbon stocks in 2050 declined compared to 2018 levels under conventional construction trends, whereas those increased under expanded wooden construction scenarios, reaching approximately 260 million t-C (about 1.3 times the 2018 level). This amount is equivalent to the carbon stock of approximately 2.17 million ha of Japan’s planted forests, or approximately 22
This study examined the climatic sensitivity of annual-ring characteristics in plantation-grown Picea glehnii from eight sites in Hokkaido, Japan, with particular emphasis on earlywood density. Earlywood density, earlywood width, latewood density, latewood width, ring density and ring width were measured using soft X-ray densitometry and analyzed using linear mixed-effects models that accounted for site- and tree-level variation. Earlywood density was negatively related to total precipitation during April-June and positively related to sunshine duration, whereas spring temperature had no significant effect. By contrast, earlywood width increased with spring temperature but showed no significant response to precipitation or sunshine duration. Latewood density was positively related to summer temperature and sunshine duration and negatively related to summer precipitation, indicating that warm, sunny, and relatively dry summer conditions promote higher latewood density. Latewood width was positively related only to summer sunshine duration. These findings suggest that trees exposed to particularly high precipitation during the early growing season may produce wood with lower earlywood density, potentially increasing the susceptibility of logs to cracking.
Middle-aged women face various stressors ranging from work-related to personal problems that brings out the sleep disturbance. In this study, we proposed essential oil prepared from the roots of Hinoki trees (Chamaecyparis obtusa) cultivated in Kagawa Prefecture as an alternative solution to sleep disturbance and proposed a home experiment to obtain realistic information compared with experiments in a laboratory environment. A single-blind cross over experiment has been conducted for 2 weeks with 12 women aged between 35 and 60 years (46 ± 6.72, mean ± SD) in each condition under Kagawa Hinoki’s root essential oil (KHREO) comparing with no scent situation (squalane oil) as a control. Physiological activity was measured by electroencephalography (EEG), and smartwatch, while psychological information was measured by the OSA sleep inventory MA. Volatile organic compounds in essential oils were analyzed using solid-phase microextraction–gas chromatography–mass spectrometry (SPME–GC–MS). This study revealed that the most abundant volatile compounds emitted from the essential oil were α-pinene, δ-cadinene, γ-cadinene, limonene, and α-muurolene. Results under visual analogue scale (VAS) show that KHREO was rated higher than the control condition in the categories of "scent strength", "scent liking", "bitterness", "relaxation", "comfort," "elegance", "nostalgia" and "woody scent". OSA sleep inventory MA also showed that participants under KHREO condition had better sleep quality especially in factor 1 (sleepiness at awakening) and factor 4 (fatigue recovery) after 13th day exposure. The EEG signal also showed increased slow-wave activity under KHREO which indicates the inducement of deep sleep from 7th day exposure. After using KHREO for 13 days, it was found that the frequency of awakenings during sleep, as detected by a smartwatch, decreased. This concluded that KHREO may play an important role in improving sleep quality by inducing deep sleep, reducing alertness during sleep and improvement from fatigue especially after 2 weeks of use.
