Volume 20 Issue 2

This experiment aimed to test the effectiveness of four antifungal chemicals in controlling mold contamination in edible mushroom production. The antifungal chemicals were terbinafine hydrochloride, prochloraz, azoxystrobin, and sodium dichloroisocyanurate. The inhibitory effects of the chemicals were evaluated for inhibition on Cladosporium sp., Aspergillus niger, and Neurospora sp. The mycelia of the three molds and Morchella sextelata were cultured individually and co-cultured on plates with different concentrations of these chemicals, and then the mycelial growth was observed. By comparing the growth areas under the same conditions, the appropriate concentrations of each chemical were determined. The results indicated that terbinafine hydrochloride and prochloraz significantly inhibited the mycelial growth of all three mold species at certain concentrations, whereas their impact on the mycelial growth of M. sextelata was not significant. These results suggest that these two chemicals are effective in controlling the mycelial growth of the three molds, potentially increasing the yield and quality of M. sextelata and reducing mold contamination during storage and transportation.

The impact of UV-B (Ultraviolet-B) radiation is reviewed relative to the biosynthesis and regulation of secondary metabolites (SMs) in medicinal plants. Plants sense UV-B radiation through the photoreceptor UVR8, which is present as a dimer in the absence of UV-B and monomerizes upon UV-B exposure, interacting with proteins to regulate gene expression. In medicinal plants, UVR8-mediated signaling can regulate the activity of key enzymes, thereby affecting accumulation of secondary metabolites. For instance, in Arabidopsis thaliana, UVR8-mediated signaling regulates the expression of flavonoid biosynthesis genes. UV-B radiation influences the yield of SMs in medicinal plants, impacting the biosynthesis of phenolics, terpenoids, and alkaloids, though the effects vary under different UV-B conditions. Furthermore, UV-B radiation induces gene regulation in secondary metabolism, with most genes being upregulated. UV-B interacts with other stress factors, e.g. chromium, UV-A, water availability, and temperature, which affect the accumulation of secondary metabolites. However, these mechanisms are complex and require further investigation. Current research exhibits limitations, including uneven study coverage, a lack of standardized methodologies, and insufficient exploration of interactions between UV-B and other factors. Future studies should expand the research scope, adopt multifactorial approaches, and investigate molecular mechanisms, thereby advancing agricultural practices and the development of medicinal plants.

The catalytic role of desulfurization fly ash (DFA) was explored as a means to upgrade biomass-derived pyrolysis gas, with a focus on integrating waste valorization and renewable energy production. Soybean straw (SS) was pyrolyzed with DFA to assess the influence on pyrolytic product distribution. The results indicate that DFA notably influenced the yield and quality of pyrolysis gas, with optimal yields achieved at specific DFA concentrations. The study also demonstrated that DFA enhanced the production of methane (CH₄) and hydrogen (H₂) while reducing carbon monoxide (CO), thereby improving the lower heating value of pyrolysis gas. Fourier-transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM) were employed to characterize the char, showing increased surface area and pore volume due to DFA addition. The study concluded that DFA is an effective catalyst in biomass gasification, providing valuable insights into its catalytic mechanisms and potential for industrial application.

Wood panel surface defect detection is critical to product quality. Traditional detection methods are time-consuming and subjective, and they can lead to economic waste, while deep learning image recognition techniques offer a new approach. However, the accuracy and convergence speed of existing defect detection techniques still require improvement. In this paper, an improved algorithm based on YOLOv8n was designed for accurate detection of wood panel defects. The C-ADown method was designed to replace traditional downsampling, while preserving high-frequency features. The combination of the Dilation-wise Residual Module and multi-scale dilation attention was employed to enhance the multiscale robustness of defect detection. A hybrid encoder was added to improve localization accuracy. The loss function was optimized to improve detection accuracy and convergence speed. Compared to the base YOLOv8 version, the improved model achieved a 6.1% increase in mAP, an 8% increase in recall, and a 3.6% increase in precision, significantly enhancing the model’s detection capabilities. The GitHub link to the improved algorithm files is as follows: (https://github.com/humblefactos1/YOLOV8-CDC/tree/main.)

The production of biomethane (Bio-CH₄) from dairy wastewater was evaluated using two types of reactors: an upflow anaerobic sludge blanket (UASB) reactor and a batch reactor, using dairy wastewater, anaerobic sludge (as inoculum), and Opuntia imbricata (as biomass substrate). The latter is a cactus known as coyonoxtle and is considered an invasive plant in northern Mexico. The wastewater was characterized in accordance with NOM-001-SEMARNAT-2021. The UASB reactor having a capacity of 4.5 L, was charged with 350 mL of sludge, 24 g of Opuntia imbricata, and 3.5 L of dairy wastewater (20.1 g/L of O₂) at pH 7.0. Batch reactors with a volume of 120 mL, were charged with 72 mL of dairy wastewater (20.1 g/L of O₂), 8 mL of sludge, and 3 pieces of O. imbricata. The results of the UASB reactor: Total specific production was 21.2 mmol of Bio-CH₄ and an efficiency in the degradation of organic matter of 70.7%, with a hydraulic retention time of 4.8 h and a total duration of 720 h. For the batch reactors: Total specific production was 11.6 mmol of Bio-CH₄ and 97.95% efficiency in the removal of organic matter, with a total duration of 192 h. The results showed an economic, efficient and sustainable way of producing Bio-CH₄.

Peels from Citrus sinensis and C. limon were used for the preparation of essential oils. The hydrodistilled citrus peels presented various compounds, including cyclohexene, 1-methyl-4-(1-methylethenyl)-, (S)- (91.8%) and 7-methyl-3-methylene-1,6-octadiene(3.40%). Compared with the essential oils isolated from C. limon, the C. sinensis essential oil showed maximum radical scavenging activity, with an IC₅₀ value of 4.31 µg/mL. Bacillus subtilis growth was generally inhibited by essential oils, and the zone of inhibition was 21 ± 1 mm, while the zone of inhibition was 20 ± 2 mm against Escherichia coli. The minimum inhibitory concentration ranged from 12 ± 1 to 128 ± 2.6 µg/mL. Similarly, essential oils presented lower minimum bactericidal concentrations against Bacillus subtilis, followed by Escherichia coli. The antimicrobial activity was tested using packed samples of fresh-cut guava fruit stored under refrigeration. The essential oil-treated guava fruit presented a decreased viable cell count. After 2 days of C. sinensis and C. limon essential oil treatment, the reduction in B. subtilis was approximately 1.7 log CFU/g compared with that of the control. In cut fruits treated with L. monocytogenes, the essential oils significantly reduced the bacterial population, and a 7 log CFU/g reduction was achieved after 8 days of treatment (p<0.05).

The modulus of elasticity (MOE) of structurally graded one-inch-thick red oak (Quercus rubra) and red maple (Acer rubrum) lumber was measured in this work. The center-point, third-point static loading tests, and the stress wave timer methods were used. The objective was to determine if there are statistical differences between three structural lumber grades based on their MOE values. The study considered both the within separated grades and the across combined grades. For red oak and red maple, significant differences in MOE values from center-point static loading tests were observed solely between Select Structural and Below-grade lumber. With the dynamic method, no significant differences were found between any visual grades, including Below-grade lumber. Regardless of the MOE determination method used, the MOE value was not useful for distinguishing the structural, No. 2, and No. 3 visual grades. The strongest correlation existed between the global MOE and the dynamic MOE, which was even higher when the analyses were conducted on separated visual grades. In the case of red maple, stronger correlations between the dynamic MOE, local MOE, and global MOE were observed when separated by visual classes, compared to the analysis conducted on the combined grades. The global MOE was found to be a better predictor of the local MOE than the dynamic MOE.

The global bamboo market reached USD 70 billion in 2022, and moso bamboo (Phyllostachys edulis) is the species with the greatest international impact. Guadua (Guadua angustifolia Kunth) is a promising species, that has been traditionally used for the construction and manufacture of handcrafts in several countries in Central and South America. In this research, progress was made in the morphological and anatomical characterization of mature guadua culms. On average the culms are 21 m in total length and there are 53.2 kg of dry biomass. The culm morphology was characterized throughout its length; the average diameter, wall thickness, and density at breast height are 14.8 cm, 21.5 mm, and 0.595 g/cm³, respectively. The fibers of the vascular bundles of internode number 7 have an average length of 2146 µm, a diameter of 20.4 µm, and a diameter of 8.7 µm wall thickness. The morphological and anatomical characteristics of guadua offer productive and comparative advantages and could be competitive in the bamboo market. The research, technological development, and innovation processes related to this material should be encouraged to promote the guadua industry.

‘Nirai’ instrument combined the ‘sanshin’ and guitar. It is a mix of the ‘sanshin’ and the guitar. Instead of using the guitar’s tuning, ‘nirai’ is tune like a ‘sanshin’. The ‘nirai’ sound were digitally captured using a PicoScope oscilloscope. The outcomes were subsequently examined utilizing PicoScope software (version 6), emphasizing Fast Fourier Transform FFT. The standard ‘sanshin’ tuning is a fifth, a root, and a fifth, so in the key of C, that would be G, C, G (GCG). When a low C (C) is added in ‘nirai’ it makes the tuning a root, fifth, root, fifth. In this work, the ‘nirai’ is being tune into the key of G, the 4^th string of ‘nirai’ can be identified as G2 (100Hz), 3^rd string as D3 (147 Hz), 2^nd string as G3 (197Hz), and 1^st string as D4 (296Hz). String 3 and 4 displayed 25 partials frequencies. String 1 and 2 displayed only 12 and 19 partials frequencies respectively. The partials of the overtones confirmed the typical sound quality of ‘nirai’ guitar. The thin string had less partials compared to the thick string. The partials are all integer number of harmonics with 24^th, 17^th and 13^th harmonics missing in string 4, 3 and 2. All harmonics appear in string 1. Even though the numbers of partials are different, with the sensation of a wooden guitar-like sound, the ‘nirai’ guitar displayed similar timbre from every string.

The oil palm frond (OPF) particleboard can be manufactured using bio-adhesive-based molasses and citric acid (MOCA) at different ratios. Before particleboard manufacture, each bio-adhesive was diluted in distilled water with a solid content of 59 wt% at three different mixture ratios of MO and CA (100:0, 75:25, and 50:50). Subsequently, the OPF particles were mixed with MOCA adhesives, oven-dried at 80 °C for 12 h, and then hot pressed at 200 °C for 10 min. In general, the basic properties and thermal behaviour of the MO adhesive changed with the increasing amount of CA. The MOCA adhesives had a lower gelation time, viscosity, pH, and a comparable solids content to that of the pure MO adhesive. The thermal behaviour of the MOCA adhesive showed an alteration in the melting point with slightly lower weight loss during thermal degradation. Applying MOCA adhesive in OPF particleboard manufacturing significantly increased its physical properties, including dimensional stabilization and mechanical properties. The OPF particleboard bonded with the MOCA adhesive at a 50:50 mixture ratio generated a product with higher dimensional stabilization and the best mechanical properties. The latter product fulfilled the JIS A 5908:2003 standard, except for the MOR and SHS parameters.