Chiang Mai Journal of Science

     High infant mortality rate is still a worldwide problem and the situation is even worse in some developing countries or regions with political instability, low economic levels and epidemic diseases. In addition, some studies have shown that infant mortality rate affects fertility rate, so it is important to reduce the infant mortality rate when China's population has already started to grow negatively in 2022. Infant mortality rate is a discrete count data. This kind of data usually does not follow the basic assumption of normality, so the use of ordinary linear regression models on it may produce inconsistent or biased estimates. Double hierarchical generalized linear model (DHGLM) are a class of models that exist specifically for count data. They can model the mean and proportion parameters hierarchically and specify random effects for the mean and dispersion which is a good solution to the problem of underestimating standard errors due to overdispersion of the data. This paper proposes a double hierarchical generalized linear model combined with the integrated nested laplace approximation within markov chain monte carlo (MCMCINLA) to analyze the data of infant mortality rate in China. At the same time, a spatial lag term is added to the model to analyze the spatial correlation of the data. Finally, the influence of economic or medical factors on infant mortality rate is analyzed and some policy suggestions are given to reduce infant mortality rate according to the analysis results.

     A large amount of spent coffee grounds has been generated from the coffee industry; therefore, much research has been conducted to investigate their applications. For textiles, nowadays an eco-trend has been receiving a greater attention, especially in the textile chemical processing, i.e. dyeing. Natural dye is an option for safer textiles but their performance is still under concerns. In this study, the utilization of a food waste, spent coffee grounds, as a raw material for natural dyeing was investigated. The dye extracted from spent coffee grounds (SCG dye) was analyzed for their chemical composition. The dyeing properties of SCG dye were conducted on cotton, silk, and nylon fabrics. Optimized dyeing performance of SCG dye on the fabrics was investigated at various dyebath pHs. An appropriate dyebath pH for dyeing SCG dye was pH 4 for all the fabric types. SCG dye showed superior dyeing on silk followed by nylon, while it dyed cotton poorly. Non-metal, bio-mordant-enhanced dyeing performance of SCG dye was achieved by post-mordanting the fabrics with tannin from cassava leaves (CL tannin). CL tannin apparently improved the color strength of the dye on silk fabric. The color fastness to washing, crocking, and light of the dyed fabrics in the absence and presence of CL tannin was also reported. SCG dye could enhance the antibacterial properties against S. Aureus for cotton, silk, and nylon, whereas it could not help prevent the growth of E. Coli at the color depth studied. It is evident that CL tannin present on the dyed fabrics improved the antibacterial properties of the dyed fabrics. All of the SCG dyed fabrics displayed excellent UV protection (UPF 50+). From this research, it points out that the SCG dye is a preferable natural dye for further development of eco-textiles with an almost entirely eco-friendly dyeing process.

     Porang is an underutilized Indonesian tuber plant that exhibits potential as an ingredient in extrusion-based snacks. This study aims to develop brown rice snacks incorporating porang flour at various die temperatures using a collet extruder to enhance their physicochemical properties. The collet extruder used in this study is a cost-effective method for installation, maintenance, and operation. The effect of die temperature (90, 100, and 110 °C) and porang (0, 5, 15, and 25 %) as independent variables were studied on the physicochemical properties, nutritional value, and sensory evaluation of extrudates. According to the experimental results, higher die temperatures significantly (p < 0.05) increased ash content (1.33 - 2.11 %), crude fat (0.91 - 2.05 %), a* value (0.96 - 4.98), water absorption index (WAI) (5.84 - 9.27 g/g),water solubility index (WSI) (6.64 - 16.05 %), DPPH free radical scavenging ability (8.14 - 18.53 %), total phenolic content (TPC) (200.61 - 426.93 mg GAE/100g d.m.), and total flavonoid content (TFC) (407.20 - 1661.11 mg RE/100 g d.m.); decreased crude protein (9.85 – 7.11%), and L* value (82.37 - 69.25). The extrudate produced at 100 °C had the highest radial expansion ratio (1.57 – 2.79 mm/mm); lowest bulk density (0.21 - 0.14 g/cm3) and hardness (2.39 - 1.30 kgf). The increased addition of porang flour significantly increased (p < 0.05) moisture content (2.01 – 2.62 %), ash content, total carbohydrate (84.83 – 86.83 %), a* value, b* value (11.80 – 16.65), bulk density, hardness, WAI, WSI, DPPH free radical scavenging ability, TPC, and TFC, whereas decreased the crude protein, crude fat, L* value, radial expansion ratio. According to the sensory evaluation results, consumers preferred the extrudates with 5 % porang flour processed at a die temperature of 110 °C over the other extrudates. Incorporating porang flour into puffed snacks could serve as a potential component in developing snacks that meet consumer demand for nutritionally beneficial products because of its low glycemic index (40.604 - 44.789). Snacks made with porang flour could provide beneficial effects for both healthy individuals and those with health concerns, making them suitable for a wide range of consumers.

     The primary purpose of the current research was to study the influence of entrapment on E. faecalis HZNU S1 under simulated gastrointestinal and different storage conditions. To achieve this, the cell was entrapped by sodium alginate (ALG) and rice bran protein (RBP) as wall materials. Probiotic survival under storage and simulated gastrointestinal conditions were explored, as well as entrapment yield (EY) and the size of microbeads. EY was around 98.5 %, while the diameter was 1.75 ± 0.15 mm. In simulated gastrointestinal tests, entrapment provided significant protection against viability loss compared to the control. Entrapped cells could be completely released within 2 h in simulated intestinal juice (SIJ) approximately. In the storage stability tests, entrapment also promoted greater protection for probiotics in relation to the free cells. The viable cells of entrapped cells retained more than 7.0 Log CFU/g after one month of storage (4 °C), and higher than 6.0 Log CFU/g at 25 °C when being stored for 8 days, respectively. Entrapped E. faecalis HZNU S1 exhibited increased tolerance to external conditions, making it a suitable candidate for delivering probiotics to enhance the related product value.

     In this study, p-tert-butylcalix[6]arene has been successfully synthesized using tert-butylphenol, formaldehyde, and KOH base catalyst. The synthesis process was carried out using a solvent-free grinding technique to minimize waste formation. The grinding technique was selected because the synthesis process was easy and environmentally friendly. With the synthesis yield of 62.58%, the product obtained was a yellow-brownish solid with a melting point >300°C, insoluble in water but soluble in methanol. The product was characterized using FTIR spectrophotometer, and resulted in spectra showing absorption band for methylene bridge (-CH2-) vibration at the wave number of 1473.62 cm-1. The results of the LC-MS chromatogram analysis showed that the molecular weight of the compound was 974.77 g/mol. The product was then tested for its ability to adsorb Cr(III) metal ions by batch method at pH 5 with variations in contact time and different initial concentrations of metal ions. Calix[6]arene was tested as a Cr(III) metal ion adsorbent because the size of the cavity diameter of calix[6]arene matches to the size of the lower period heavy metal cation. The results showed that the amount of adsorbed metal increased with the increasing of the contact time and reaches stability within 120 min. The adsorption capacity value was 7.414 μmol/g with a Gibbs adsorption energy value of -26.198 kJ/mol.

     Low-cost natural materials-mediated adsorbents for the removal of dye pollutants from water are gaining popularity over chemical adsorbents due to their eco-friendliness, widespread availability, and ease of manufacture. A CaO-derived from eggshell was used to alter the surface of zinc-manganese-ferrite (Zn_0.6Mn_0.4Fe₂O₄) nanoparticles by the post-precipitation method. The CaO/Zn_0.6Mn0.4Fe₂O₄ nanocomposite was studied using FT-IR , XRD and SEM, and utilized for the removal of Rhodamine B dye. The adsorption efficiency of 10 mg L^-1 RhB reached 75% at pH 4.0, 60 min of shaking, and 2.0 g L^-1 of adsorbent. The intra-particle diffusion process was a rate-limiting phase, and the results matched the pseudo-second-order kinetics model. Adsorption data were well-fitting by the Langmuir isotherm model, with R2=0.989, KL =0.232, and maximal monolayer capacity (qmax) of 30.7mg.g^-1.The Tempkin isotherm revealed that the lateral repulsive forces are non-significant. The D-R model revealed positive adsorption-free energy confirming an endothermic chemical adsorption process. The Fenton-like catalytic degradation showed a removal of 98% at 80 min and increased by increasing the TDS of the medium.

     Bacterial cellulose (BC), synthesized by acetic acid bacteria, provides a versatile biofilm with promising potential for probiotic delivery. This study investigates the encapsulation of the probiotic yeast Saccharomyces boulardii within BC to improve its resilience against harsh digestive conditions. By co-culturing Komagataeibacter rhaeticus JYCB292, a BC-producing bacterium, with S. boulardii, we developed BC beads that encapsulate the yeast, forming a structure similar to coconut jelly. To demonstrate the protection provided by bacterial cellulose encapsulation, we used YFP-labelled S. cerevisiae W303, a species closely related to S. boulardii. The results showed that encapsulated yeast retained fluorescence, indicating high survival rates after exposure to simulated digestion and cold storage, while non-encapsulated yeast lost fluorescence. This highlights the potential protective capability of bacterial cellulose for S. boulardii. Scanning electron microscopy further confirmed the successful encapsulation of S. boulardii within bacterial cellulose. Additionally, co-culturing in a tea medium at 28°C for one week produced a fermented beverage with polyphenol (0.05 ± 0.01 gallic acid mg/mL) and flavonoid content (0.13 ± 0.03 quercetin mg/mL), as well as antioxidant activity (0.06 ± 0.005 FeSO₄ mg/mL in FRAP analysis, and 88.56 ± 1.42 % in DPPH scavenging assay), comparable to that of tea fermented by commercial kombucha starters. This encapsulation technique not only enhances probiotic stability in the digestive tract but also provides a novel approach to creating functional beverages with potential health benefits. These findings suggest that BC-encapsulated probiotics in a tea-based medium could serve as a stable, health-promoting alternative to traditional kombucha products.