Asia-Pacific Journal of Science and Technology

Investigation of nanofluid molten salts in a thermocline tank as a thermal energy storage system

2023-09-08T13:44:49+07:00

Nanoparticles were prepared and incorporated into molten salts to form a nanofluid system for use in a concentrated solar powerplant (CSP). Particle sizes of both the nanoparticles and incorporated molten salts were analyzed from images captured by scanning electron microscopy using image processing software. The heat transfer fluid was prepared via a two-step method by blending four molten salts (KNO₃, NaNO₃, LiNO₃, and Ca(NO₃)₂.4H₂O) and anodic aluminum oxide (AAO) at 180°C for 360 minutes. Results showed that after the anodization process, aluminum A5052 transformed the film surface into metal oxide (anodic aluminum oxide) with particle size smaller than 56.3 nm. Incorporation of aluminum nanoparticles into the molten salt matrix increased particle size to 100 nm due to the chemisorption of molten salt by hydroxide functional groups on the AAO surface during the heat transfer process. Addition of AAO improved the discharge power provided by the upright thermocline tank.

Survival of probiotics Lactobacillus acidophilus TISTR1338 in a synbiotic-supplemented plant-based protein powder under various pH and temperatures

2023-08-18T10:49:45+07:00

The demand of plant-based protein has been remarkably increased, leading to the development of various plant-based protein products. Supplementation of synbiotic is an effective approach to improve food function. This study aimed to develop the formulation of plant-based protein product supplemented with synbiotic which provides high survivability of probiotic through various harsh conditions. Pea protein isolate (PPI), inulin, and glycerol at ratio 2:1:1 was supplemented with probiotic strain (Lactobacillus acidophilus TISTR1388) to develop as encapsulated synbiotic plant-based protein powder (SPBP). The developed formulation provided probiotic survival rate after freeze-drying and gastro-intestinal (GI) tract conditions at 95.0±2.1% and 62.4±6.1%, respectively. Whereas, probiotic as free-cells showed survival rate after freeze-drying at 78.9±0.4% and no survival cell was observed after GI tract digestion. Scanning Electron Microscope (SEM) analysis demonstrated SPBP's remarkable capacity to perfectly entrap probiotic cells with no visible cell damage. Herein, the stability of the SPBP was tested through various pH levels (3, 5, 7, and 9) and temperature levels (6±2°C, 26±2°C, and 55±2°C) in order to investigate the possibility of applying this product to various food categories. Results showed that developed SPBP survived through all tested pH and temperature levels for 3 h at least 88.9±6.6%. Shelf-life evaluation showed that SPBP provided survival rate of probiotic cells up to 96.2±2.4% an a_w of 0.09±0.01 after 12 weeks of refrigerated storage. Overall, results revealed that SPBP had a strong possibility of being employed as a probiotic stabilizer that may be further developed for a functional food product.

National yield reference for sugarcane management: Thailand case study

2023-12-19T16:47:08+07:00

In this study, a tool is proposed to assist small-scale sugarcane farmers in Thailand in justifying their field management practices. The tool is a master chart derived from the relationship between annual average rainfall and national sugarcane yield and consists of three curves: the mean, the upper bound, and the lower bound. The chart allows farmers to assess the condition of their fields by plotting the coordinates of annual rainfall and yield to observe the position in relation to the three curves. The ratio of actual yield to the upper bound yield also helps in the justification process. This proposed method offers an alternative to the traditional yield gap technique, which is difficult to obtain, unreliable, and not standardized for the whole country. The relationship equation of the annual rainfall and detrended yield has been formulated from the hypothesis that their derivative follows an exponential decay. After obtaining the trend (mean), the upper and lower bounds can be derived for the 95^th and 5^th percentiles, respectively. The master chart, along with the yield-ratio concept, has been tested against three field observations and four field experiments.

Community of endophytic bacteria colonized in Jerusalem artichoke observed under molecular technique

2023-10-03T10:37:10+07:00

Plant associated bacteria, named endophytic bacteria, colonize inside plant organs and mostly interact via plant growth promotion. The location of bacteria inside plants is different depending on bacterial species; likely, the bacterial diversity is different depending on plant species and stress environments. The bacterial community was determined in parts of Jerusalem artichoke which grew under well watering and deficient water conditions with inoculation of endophytic bacteria, Rossellomorea aquimaris 3.13, Micrococcus luteus 4.43 and Bacillus velezensis 5.18. The techniques used to determine community and colonization were denaturing gradient gel electrophoresis and transmission electron microscopy, respectively. The root showed the highest bacterial diversity, particularly under drought condition. The endophytic bacteria inoculated in the plants had negative effect on bacterial community. In contrast, the drought stress did have an effect on bacterial community. The majority of endophytic bacteria were members of gamma-Proteobacteria and Firmicutes (Bacillus spp.). The colonization of three endophytic bacteria was observed in the xylem vessel of stem and root of Jerusalem artichoke. Results showed that the endophytic bacteria were localized where they were isolated, leading to an understand of the relationship between endophytic bacteria and plant host.

Effect of corn starch on sensory quality, physical quality, and consumer acceptance of gelatin-free pudding products

2023-08-31T11:16:33+07:00

This research aimed to investigate sensory quality, physical quality (values of color and texture) and consumer acceptance of pudding products. The experimental factor was the use of corn starch in place of gelatin in different ratios of four formulations: gelatin pudding (control), 4% corn starch pudding, 6% corn starch pudding, and 8% corn starch pudding. According to a sensory evaluation, the 4% corn starch pudding received the highest accepted sensory test scores and was the best formulation for replacing gelatin with corn starch. Meanwhile, a physical quality analysis showed that the color and texture values of the pudding were the lowest, but it showed that the lightness value was high when compared with other formulations. A study on consumer acceptance of 4% corn starch pudding (final product acceptance) found that acceptance was at a high level. The average score of all attributes was 7.61. From analysis of consumer attitudes, it was found that 97% of consumers accepted the pudding products, 98% would decide to buy the pudding products when they were on the market, and 32% rated the products as a novelty. Additionally, when the price of gelatin pudding (control) was compared to the price of 4% corn starch pudding, it was found that corn starch pudding was cheaper.

A comparative study of the structure and morphology of graphene oxide films on glass and aluminum supports by using dip coating

2024-02-19T16:53:44+07:00

In this work, graphene oxide (GO) coating was deposited on glass and aluminum substrates via dip coating. The structural appearance of the coating layer deposited on glass and aluminum substrates was demonstrated using scanning electron microscopy and atomic force microscopy (AFM). Images of the coated substrates were analyzed using ImageJ software. Results show that the probability of distribution can be determined from a histogram of heights measured by AFM. The surface roughness rate of the coated glass and aluminum substrates were compared. In addition, the image software can be successfully used to evaluate starch granule size and shape. The thicknesses of the deposited film were about 0.09 and 0.07 µm for GO coating on aluminum and glass substrates, respectively. The weight loss of the substrates coated with different concentrations of sodium chloride solution under the influence of different times was examined. Results showed that the corrosion rates using the weight loss method for aluminum samples were less than the corrosion rates of coatings on glass substrates.

Andrographolide production in in vitro cultures of Andrographis paniculata (Burm.f.) Nees

2023-09-26T10:36:13+07:00

Fah Talai Jone, Andrographis paniculata (Burm.f.) Nees is a Thai medicinal plant that has been used for Covid-19 treatment as alternative medicine. Pharmacologically active diterpene lactones such as andrographolide accumulate in its leaves. This study investigated the combinatorial effects of 1-naphthaleneacetic acid (NAA) at 0, 0.5 and 1.0 mg/L and 6-benzyladenine (6-BA) (at 0, 5, and 10 mg/L) on the development and accumulation of andrographolide in A. paniculata in vitro using Murashige and Skoog, 1962 (MS) semi-solid medium. Results showed that lateral bud cultures had a survival rate of 33 to 73%, with good callus development when cultured on MS medium containing BA 10 mg/L and MS added with BA 10 mg/L and NAA 1.0 mg/L. Seeds germinated in vitro had a 100% survival rate and developed into mature plants with leaves and roots of 5-10 cm after 30 days of cultivation. Plantlets grown in vitro contained andrographolide at 1.14 % of dry weight, while plants grown in soil for 120 days had andrographolide content at 1.5% dry weight. However, andrographolide was not detected in the callus of treatments that contained BA, NAA alone or in combination. The in vitro plantlets had leaves and roots with lengths of 5-10 cm within the 30-day culture period and accumulated andrographolide at 1.14% dry weight.

Walking distance improvements in chronic obstructive pulmonary disease patients after home-based daily respiratory muscle training: A pilot study

2023-07-16T21:22:31+07:00

This study investigated the effects of home-based daily inspiratory muscle training (IMT) on inspiratory muscle strength and exercise capacity among chronic obstructive pulmonary disease (COPD) patients. The participants comprised 14 elderly men with moderate to severe COPD, who were randomly divided into two groups, the IMT group (n = 7) and the control group (n = 7). In the IMT group, participants followed a daily home-based IMT exercise program at moderate resisted load for 6 weeks, while the control group had no intervention. Maximal inspiratory pressure (MIP, an index of inspiratory muscle strength), 6-minute walk distance (6MWD) and cardiovascular responses following the 6-minute walk test (6MWT) were examined at baseline and after the program. The results showed that, after the training period, the inspiratory muscle strength and 6MWD values in the IMT group were significant increased compared with control group (p = 0.010 and 0.038 respectively). Greater improvement in cardiorespiratory responses following 6MWT was observed in the IMT group, as exhibit by a significant decrease in dyspnea and heart rate compared with the control group. Additionally, inspiratory muscle strength was significantly positively associated with 6MWD (r = 0.735, p = 0.003). In conclusion, a 6-week home-based IMT exercise program is an effective intervention for increased respiratory muscle strength, increased exercise capacity, and attenuated dyspnea among COPD patients. Such, a program might be a feasible alternative for COPD patients, especially those who are unable to adhere to the aerobic exercise recommendations, to enhance their exercise.

Quantitative phase analysis of electron beam weldments of copper and stainless steel 304 using XRD and SEM-EDX

2024-01-17T13:39:25+07:00

Electron beam welding is performed to join Copper and Stainless steel 304 dissimilar metals for Aerospace applications which demand high-quality defect-free welds. This is a complex process as both the metals possess different material properties. During melting both metals melt and a transition region is formed where both the copper and stainless steel crystals merge together and form weldment. Since both materials possess different properties there are chances for defects or lattice distortion in the interference region. Therefore, the formation of the sigma phase in the weldment is an area of research for material researchers to analyse the crystal structure. In this paper, a quantitative phase analysis is carried out using X-Ray diffraction in the weldment and the crystallographic structure of the weldment grains is found and the behaviour of weldment is analysed towards weld quality.

The relationship between soil fertility, phosphorus uptake, and crop yields of paddy (Oryza sativa l.) under different farming systems of rice field

2024-02-28T16:40:38+07:00

This study aims to determine the influence of the differences in rice field farming systems on soil fertility index (SFI), phosphorus uptake, and crop yields of paddy, as well as provide appropriate and sustainable land management to ensure crop yields. To achieve these objectives, a descriptive-exploratory method through a survey conducted with purposive sampling in Girimarto District, Wonogiri Regency, Indonesia, was adopted. The sampling points were determined on a working map consisting of 6 land map unit (LMU), with 4 points per LMU. Parameters observed included C-microbial biomass, earthworm population, soil pH, N-total, P-available, K-available, P-total, Organic-C, soil oxidation-reduction, Cation Exchange Capacity (CEC), and Base Saturation (BS). Soil and plant sampling was conducted during the maximum vegetative phase. SFI was determined through Principal Component Analysis (PCA) and data scoring. Furthermore, data were analyzed using One-way Analysis of Variance (ANOVA), DMRT, and Pearson’s correlation test. The results showed that organic farming system had a higher SFI (0.78) and P plant uptake (2.21%) compared to semi-organic and conventional methods. Soil management options suitable for the prevailing conditions include adding compost into non-organic system, maintaining organic rice field management, expanding organic cultivation area, and adding biofertilizers.

Enhancing the performance of ECC through chemically treated Jute fibre reinforcement

2024-03-12T13:53:50+07:00

In this comprehensive study, the potential of chemically treated jute fibres as a reinforcement in Engineered Cementitious Composite (ECC) is thoroughly investigated. The alkali treatment process significantly enhances the interaction between these fibres and the cement matrix, resulting in substantial improvements in the mechanical properties of the concrete. Various parameters, such as direct tensile strength of the fibre, compressive strength, flexural strength, direct tensile strength of ECC, modulus of rupture, modulus of elasticity, bond strength between ECC and concrete, and bond strength between ECC and steel, are meticulously evaluated for both treated and untreated jute fibres integrated into the concrete. The research underscores the critical importance of maintaining an optimal fibre content, typically around 1.5%, to achieve a well-balanced mix design that ensures optimal composite performance. The study places strong emphasis on the adoption of sustainable and eco-friendly construction practices by incorporating biodegradable materials. Furthermore, it highlights the pivotal roles played by aspect ratio and interfacial bonding in influencing the stiffness, strength, and overall durability of the concrete. Ultimately, this research contributes valuable insights that advance the field of composite materials and encourage the adoption of sustainable construction approaches.

Effects of polyhydroxy compounds on the properties of starch-protein composites modified by high-pressure processing

2023-09-26T12:29:17+07:00

Biopolymer composites based on starch-protein blends are responsible for a variety of food properties. The aim of this research was to study the effects of high pressure processing (HPP) and polyhydroxy compounds on the properties of starch-protein composites as determined by the degree of starch gelatinization (DG), surface hydrophobicity (H₀), exposed and total free sulfhydryl (SH) groups, and morphology as they relate to their pasting properties. Tapioca starch (TS) and whey protein isolate (WPI) were chosen to form composites. The impacts of pressure ranging from 300-600 MPa on tapioca starch-whey protein isolate composites (mTS-WPI) with and without polyhydroxy compounds were investigated. Increased pressure up to 500 MPa significantly increased the DG, H₀, and exposed free SH groups of the composites, with dramatic increases observed at 600 MPa. HPP also altered the microstructure of the composites, especially at 500 and 600 MPa of HPP. Addition of polyhydroxy compounds decreased the DG, H₀, exposed free SH group content of the composites in a concentration and compound type dependent manner. Addition of glucose had more effect on the mTS-WPI than that of fructose and glycerol at the same concentration. Polyhydroxy compounds also had an impact on the pasting properties of the composites, exhibiting higher pasting viscosity and temperature than composites to which no polyhydroxy compounds were added. This research indicates that different types and concentrations of polyhydroxy compounds could be used to stabilize and prevent starch gelatinization and protein denaturation in starch-protein based foods that are treated by HPP.

Evaluation of transdermal patches made from Garcinia mangostana Linn. peel extract and natural rubber

2023-11-09T16:08:54+07:00

Transdermal drug delivery systems (TDDS) are a popular research focus in pharmaceutical technology and a commonly produced pharmaceutical product worldwide. Utilizing these systems helps mitigate the disadvantages of other administration methods, such oral and parenteral. The aim of this study was to evaluate the properties of transdermal patches containing Garcinia mangostana Linn. peel extract with natural rubber content. Formula 1-4 (F1-4) transdermal patches with natural rubber were produced with hydroxypropyl methylcellulose (HPMC) and low protein rubber (LPR). The patches were examined to evaluate physicochemical properties and drug release characteristics. The casting evaporation method was utilized to produce transdermal patches that are smooth, dry, and white in color. pH values ranged between 5.8-6.2, and tensile strength values were 2.35 – 3.75 N/mm. The patches exhibited a thickness range of 0.47-0.55 mm. The weight values were in the range of 2.2-2.5g. and percent moisture and protein content ranged between 4.01-6.74 and 1.32-3.25 respectively. F-2 patches exhibited the highest drug entrapment capacity (71.02 %) and release efficiency (26.96% over 360 minutes). Therefore, the findings of the study suggest that F-2 patches can be developed as commercial alternative pharmaceutical products.

Short-term impact of mini-marathon running on alteration of blood lipoproteins

2024-04-17T14:35:04+07:00

Individuals are increasingly aware of their health and often engage in various exercises to improve it. Mini-marathon running has become particularly popular due to its minimal equipment needs and its benefits for both physical and mental well-being. Lipoproteins, different forms of adipose tissue, are crucial indicators of general health. However, studies on how mini-marathon running affects lipoprotein levels are limited. Therefore, this study involved ten healthy volunteers who participated in a mini-marathon to investigate potential changes in their lipoprotein levels. Blood samples were collected before and after the test to measure any changes. The results indicated that participating in a single mini-marathon significantly reduced weight, body fat percentage, body mass, cholesterol, high-density lipoprotein (HDL), and low-density lipoproteins (LDL) levels (Z= -1.972, -2.002, -2.275,
-3.05, -2.468, -2.200 with p-values of 0.049, 0.045, 0.023, 0.002, 0.014, and 0.028, respectively). However, the effects on lipoprotein patterns varied among individuals, likely due to the unique physiological responses triggered by the run. Consequently, the researchers recommend further studies to explore the long-term effects of physical activity on lipoprotein fluctuations.

Multi-Temporal InSAR analysis for monitoring the ground deformation of Mount Sinabung

2023-12-21T09:27:14+07:00

Deformation of a volcano’s surface is a geohazard caused by volcanic activities and seismicity. Monitoring the deformations serves as a part of an early warning system that can mitigate disasters. Between 2017-2022, Mount Sinabung volcano’s ground deformation was monitored and analyzed using Multi-Temporal Interferometry Synthetic Aperture Radar (InSAR) and spatial statistics. The results showed substantial changes in surface elevation. The maximum monthly inflation was 4.7 cm in 2020, while the maximum monthly deflation was -4.7 cm in 2018. The correlation between the number of monthly eruptions and deformation patterns was very weak at 0.09 to -0.09, which indicated that the volcano’s eruptions did not lead to ground deformation around Mount Sinabung and vice versa. Moreover, the ground deformation at Mount Sinabung did not indicate a consistent or periodic pattern. Some areas experienced higher deformation rates than others, depending on the land cover and underground magmatic activities. The volcano surface has been inflating over the past six years with an average rate of 0.14 cm/year. Data from sample observation points recorded the highest rate of 1.74 cm/year at the mid-slope, and the lowest rate of 0.62 cm/year at the foot of the mountain. The mountain caldera showed a ground surface inflation rate of 1.53 cm/year. The data showed that, despite the absence of an explosive or magmatic eruption since Mount Sinabung returned to activity, its caldera and surface continue to undergo deformations at higher velocities. Future explosive eruptions are expected, and preemptive preparations for potential disasters should be planned.

Study on kinship among kepok banana cultivars using resistance gene analogue (RGA) based single nucleotide polymorphism (SNP) markers

2023-11-28T13:54:31+07:00

The primary goal of the research is to implement Resistance Gene Analog (RGA) markers to determine the kinship of three kepok banana cultivars from Bandarlampung: kepok abu (AAB genome), kepok batu (ABB genome), and kepok kuning (BBB genome). The banana RGA genome sequence from GenBank (ID: KF034945 to KF034953) was used to examine the sequencing data for parallels. Phylogenetic trees were constructed with 1000 bootstrap replicates of neighbor-joining using MEGA X. It was determined that the primer SNP2-MNBS-Ref. may identify Single Nucleotide Polymorphism (SNP) sites at the 327th nucleotide base pair, which is the cytosine nucleotide base, in the RGA of the three banana cultivars that have been validated in GenBank. The phylogenetic tree showed that the three banana cultivars have a common ancestor, which is Musa balbisiana cv. Klutuk Wulung. With a genetic distance of 29%, the progenitor created a branch where Kepok Batu and Kepok Kuning are in the same clade as Musa acuminata subsp. burmannica cv. Calcuta4. Kepok Abu is in the same clade as Musa acuminata cv. Rejang and Musa acuminata subsp. Malaccensis, with a genetic distance of 28%. This indicates that Kepok Batu and Kepok Kuning are one cultivar but distinct variations. Consequently, it may be said that each of the three banana cultivars studied has an SNP location in the R gene. Kepok Abu's reduced genetic distance indicates that it may be a good source of R gene material for the Musa improvement program, which aims to produce a cultivar with increased pathogen resistance.

The development of Thai monosyllable word lists for word recognition scores testing in pre-school age children

2024-02-02T09:27:50+07:00

The study aimed at developing a Thai version of monosyllable word lists and picture lists to provide clinical hearing evaluations for pre-school children and to validate the reliability of the Thai version of the monosyllable word lists for two different age groups (2-3 years vs. 4-5 years). The monosyllable word lists and picture lists were developed in accordance with the following steps: 1) the familiarity of 100 words was chosen; 2) the pictures that represented the meanings of the matched 80 words were developed; 3) both the receptive and expressive vocabulary were evaluated in 62 children 2-3 years of age (Group 1) and in 62 children 4-5 years of age (Group 2); 4) monosyllable words were analyzed using a computerized speech lab and were arranged into sets of word lists (Khon Kaen University (KKU) kid word lists-A for Group 1 and KKU kid word lists-B for Group 2) with phonetically balanced fundamental frequency, the Thai five tones, and the initial consonants; 5) the word lists were recorded; and 6) The KKU kid word lists-A & B were validated with 31 children from each group, respectively. KKU kid word lists-A had word recognition scores (WRS) with a mean of above 90% for each list in passing and referring to the hearing screening ears. KKU kid word lists-B had a WRS of over 92% for each list. The development of the Thai monosyllable word lists was determined to be appropriate for assessing the WRS of pre-school children for conducting clinical hearing evaluations.