Volume 20 Issue 1

The extracts of Schotia brachypetala were tested against the molecularly identified fungi Alternaria alternata, Botrytis cinerea, and Fusarium oxysporum, which cause early blight of tomatoes, gray mold of cucumber immature fruits, and Fusarium wilt, respectively. Leaves and branches of S. brachypetala were extracted using acetone and bio-assayed for their antifungal activity at 2%, 4%, and 6% when applied to white mulberry wood samples. Using high-performance liquid chromatography analysis, the most abundant compounds in leaf extract were kaempferol (37900 µg/g extract) and gallic acid (7480 µg/g extract), and in branch extract were gallic acid (3120 µg/g extract) and chlorogenic acid (1320 µg/g extract). By increasing the extract concentration to 6%, the percentage inhibition of fungal mycelial was significantly increased compared to the positive (Cure-M) and negative control samples. This study indicates that extracts from leaves and branches of S. brachypetala can be effective as bio-based agents in wood protection and that they can prevent the growth of pathogenic fungi.

This study was conducted in a kindergarten classroom in the Ayancik district of Sinop province, Türkiye, and examined indoor air quality under five scenarios. The measured parameters included formaldehyde, TVOC (total volatile organic compounds), PM10 and PM2.5 (particulates), humidity, temperature, airflow velocity, and illumination level. The study found that using wood and plastic materials, such as toys, tables, and chairs, significantly influenced the indoor air quality in the kindergarten environment. Wood materials reduced formaldehyde, TVOC, and particulate matter (PM) levels. Formaldehyde levels ranged from 0.03 to 0.22 ppm, TVOC values from 0.001 to 0.003 mg/m³, PM10 levels from 16 to 52 µg/m³, and PM2.5 levels from 15 to 46 µg/m³. In Scenario 5, the lowest levels of formaldehyde and TVOC were recorded. These findings offer important insights for improving air quality in kindergartens and provide a foundation for future research. Careful selection of toys, design elements, and materials in kindergarten classrooms is critical for protecting children’s health and promoting development. Prioritizing high-quality indoor air in these environments is essential for enhancing children’s learning, health, and overall well-being.

The hasapi of the Batak Toba from Sumatra, Indonesia is a plucked bowl-lute chordophone. Hasapi is a fretless chordophone with two strings. The tuning for the hasapi used in this study is based on the transcription of the song ‘Horbo Paung’ played in F major by Sam Sitio. The tuning used for the 2^nd string is C4 (Do for open string) followed by D4, E4, and F4 for 1^st, 2^nd, and 3^rd finger, respectively. The 1^st string was tuned to G4 (So for open string), followed by A4, B4, and C5 for 1^st, 2^nd, and 3^rd finger, respectively. At higher notes (1^st string) the spectra did not display many harmonics, i.e., less partials compared to the lower note (2^nd string). Both strings showed a regular signal, whereas the highest note C5 (the highest fundamental frequency from the 1^st string) showed an irregular pattern with no significant overtone frequency. The intensity of the partials in both strings displayed the reduction in amplitudes i.e. not proportional to increasing harmonic frequency. The timbre from Adobe Audition showed that the time frequency analysis (TFA) was in accordance with the Picoscope spectra. Only TFA from C5 showed irregular pattern with respect to the Picoscope output.

Even though making thin sheets of cellulose nanofiber by a papermaking-like process is straightforward, obtaining thicker papers or plates is extremely time consuming. Dewatering is exceedingly slow as the nanocellulose is deposited on the filter paper during filtration, hindering water flow. This study proposes a simple device that speeds up dewatering through the application of air pressure on the aqueous suspension being filtered. A relative pressure of 0.5 MPa reduced the dewatering time of 72 h for a conventional vacuum filtration to 16 h without compromising the mechanical properties of the final molded material.