This study assessed the drying behaviour of young and mature Bambusa vulgaris culms and evaluated their utilisation potential. Two and four-year old Bambusa vulgaris culms were harvested and prepared to the required length of 21 internodes. The first seven internodes were taken as the bottom, the second seven were taken as middle and the last seven internodes were taken as the top. The study used samples from the bottom and top. Physical properties, including basic density and moisture content, were determined in accordance with ISO 13061–2 (ISO 2014) and EN 13183–1 (EN 2002), respectively, while shrinkage properties (radial, tangential, longitudinal and volumetric) were determined following established procedures. For the bottom and top portions of the mature bamboo after 18 days of drying, radial shrinkage values were 3.31% and 5.01%, tangential values were 4.95% and 5.78%, and longitudinal values were 0.28% and 0.35%, respectively. For the bottom and top portion of two-year-old culms, the values were 15.0% and 18.6% for radial shrinkage, 20.5% and 25.8% for tangential shrinkage and 0.46% and 0.47% for longitudinal shrinkage, respectively. The tangential shrinkage values were higher than the radial and longitudinal shrinkage values. The moisture content of the bottom part of the mature bamboo culm after 3 and 18 days of drying were 31.4% and 12.2%, while the young culms had values of 53.5% and 27.8%, respectively. Mature bamboo culms had better drying behaviour than young culms. Consequently, mature bamboo culms are more suitable for use in engineered composite materials.

The strength behavior of Corn Husk Ash polymer concrete reinforced with coconut fibre was investigated in this study. The study assessed the suitability of using coconut fibre in concrete to improve its strength properties. The concrete was prepared and cured based on British Standard. Different proportions of the coconut fibre as well as the Corn Husk Ash (CHA) polymer were used in the concrete mixes, with a total of nineteen different mix proportions. The specimens were cured for 28, 90 and 180 days. Compressive strength, tensile splitting strength, torsion and toughness were determined using specimens from the various mixes. Tests were conducted on the 28^th, 90^th and 180^th days of curing, following (Compression) and (Tensile Splitting). Analysis of Variance (ANOVA) test was conducted to determine the differences in the behavior of the different mixes as well as the correlation between the different constructs. The addition of coconut fibre to the concrete improved the toughness, torsion and to some extent the tensile strength of the concrete at the standard curing age of 28 days. CHA as an additive to the concrete resulted in a positive relationship with the Torsion and Toughness properties of concrete at later curing age at 1% level of significance (r = 0.480 and r = 0.730, p < 0.01 respectively). Compressive strength of concrete correlated positively with tensile strength, torsion and toughness of concrete (r = 0.830, r = 0.721 and r = 0.452 respectively with p < 0.01).

1. Wood density is one single property that has wider application in evaluating mechanical, physical, and other wood qualities which subsequently affects wood product quality. According to Tsoumis ...

This study sought to assess the density and anatomical features of young and old Bambusa vulgaris Schrad. ex JC Wendl. culm heights and, therefore, evaluate their influence on the utilization potential of the culm as a sustainable structural material. Bambusa vulgaris culm of 2-year and 4-year-old were harvested and prepared to the required length of 6 meters for the study. Basic density and anatomical features were carried out. The results showed that the basic density of old bamboo ranges from 652.91kg/m³ to 729.06kg/m³, while the young bamboo ranges from 342.33kg/m³ to 509.52kg/m³. The vascular bundle arrangement was found to be in Type III and Type IV for the culm heights of both young and old bamboo. The average vascular bundle radial diameter ranged from 761.13μm to 890.78μm for the old culm and 727.16μm to 844.83μm for the young culm. The average vascular bundle tangential diameter ranged from 499.44μm to 533.49μm for the old culm and 425.56μm to 483.56μm for the young culm. The radial diameter of the metaxylem vessel of the old culm ranged from 216.81μm to 54.74μm, while 214.23μm to 73.86μm were for the young culm. Parenchyma tissues ranged from 35 to 70 for the old bamboo culm and 45 to 75 for the young bamboo culm. Vessel proportion ranged from 612 for the old culm while the young culm ranged from 511. Fiber proportion ranged from 22 to 54 for the old culm and 19 to 44 for the young culm. Old bamboo had better vascular bundle properties than that of young bamboo. The density is significantly correlated positively to the anatomical properties. Old bamboo is more suitable to be used as the engineered composite material due to its better anatomical features across the culm wall thickness.

¹²³I thyroid scintigraphy can be performed with either a low energy or medium energy collimator. The high-energy photon emissions from ¹²³I cause septal penetration with scattered photons, which deteriorate image quality. The aim of this study is to evaluate the impact of collimator choice on ¹²³I thyroid scintigraphy in clinical practice. Methods: Forty seven patients who received thyroid planar scintigraphy with both a low energy high resolution (LEHR) collimator and a medium energy (ME) collimator were prospectively recruited using the same imaging protocol. Image quality, collimator sensitivity, and estimation of thyroid size were assessed between LEHR and ME collimators, and were compared with thyroid ultrasonography as the gold standard. Results: Images acquired with the ME collimator demonstrate less scattered background noise, improved thyroid to background contrast, and increased sensitivity in the thyroid gland compared to images acquired by the LEHR collimator. Manual measurement of the thyroid length is more accurate by using the ME collimator. Automatic estimation of the thyroid area size by using the same thyroid cutoff threshold is larger in ME collimator images than in LEHR collimator images. Conclusion:¹²³I thyroid scintigraphy using the ME collimator generates cleaner images with less background noise and has higher collimator sensitivity for thyroid imaging compared to the LEHR collimator. Different thyroid cutoff threshold should be used to estimate the thyroid area size and volume between low and medium energy collimators.