bluuebunny/crossref_metadata_2025 huggingface dataset:
Investor’s hindsight effect and true timing ability of tax saving mutual funds
Authors:   , Chaleoykitti Krittapon
Published: September 2023

This paper analyze the cash flow timing ability of mutual fund investors both non-tax-saving and tax-saving funds which have constraints such as lock-up period to block investor’s ability to make cash flow timing, after controlling for the hindsight effect. We analyze the sample of Thai mutual funds in the period of 2006-2017.

We find that investors have bad timing ability and make return underperformance. The tax-saving funds that have investment constraints to block investor’s timing ability have better timing ability and tends to have smart money effect and make return over performance. In addition, volatility affect investors to increase the return under or over performance based on investors have smart or dump money effects. Lastly, large asset under management affects investors are hard to make cash flow timing.
Development of value added unripe papaya flour from waste product of fruit industry
Authors:   , Joymak Waralee
Published: September 2023

Papaya fruit (Carica papaya L.) belonging to Caricaceae family is recognized as a good source of dietary fiber and antioxidants. The objective of this study was to develop the unripe papaya flour (UPF) from waste fruit product. The study was also investigated physicochemical, functional properties of UPF and its addition of pancake. First, the small pieces of unripe papaya were heated by hot air oven, then ground by using a high-speed universal grinder and sieved through a 100-mesh sieve. The particle size of UPF was 140.8±2.1 µm with randomly irregular shape. The hydration properties of UPF was higher than wheat flour, whereas bulk density was not significant differences. Total polyphenol and ᵦ-carotene contents of UPF were 85.7±1.6 mg gallic acid equivalent/100 g dry weight and 39±3.3 µg/100 g dry weight, respectively. In addition, UPF had the ferric reducing antioxidant power (411.6±38 µmol FeSO4 per 100 g DW) and DPPH free radical scavenging activity (37.87±3.69 mg vitamin C equivalent per 100 g DW) higher than that of wheat flour. Moreover, UPF had the ability on bind bile acid and interfere the cholesterol micellization. Thereafter, the replacement of wheat flour with UPF into pancake (0%, 5%, 10%, and 20%) presented the darker shade of brown color on their surface. Hardness and cohesiveness of pancake were increased in a higher level of replacement. However, pancake with UPF (20%) could attenuate the glucose release under simulated digestion. Moreover, pancake with UPF had significantly lower predicted glycemic index when compared to the control pancake. Undigestible starch in pancake was also increased when the replacement of UPF was increased. Furthermore, pancake with UPF significantly increased total polyphenol content and antioxidant activity. In sensory evaluation, the taste and aftertaste parameters were significantly decreased in pancake with 20% UPF. However, the overall acceptance showed no significant difference among all groups. The results suggest that the unripe papaya flour can be regarded as a good ingredient for natural antioxidants for development of healthy products.
Antioxidant and antimutagenic activity of extracts from pericarp and seed of zanthoxylum limonella alston
Authors:   , Wipoosanapan Patamawan
Published: September 2023

This study was conducted to investigate the antioxidant and antimutagenic activity of Zanthoxylum limonella seed extract and that of Z. limonella pericarp extract. The total phenolic contents and antioxidant activity assay including DPPH assay and FRAP assay were performed. The results showed that the antioxidant activity of pericarp extract was higher than that of the seed extract. The direct mutagenicity assay was determined, with and without nitrite treatment using the Ames test towards Salmonella typhimurium strains TA98 and TA100. The mutagenic modification assay was performed by measuring the interfering effect of the pericarp extract and the seed extract on the formation of standard mutagens during the reaction between 1-aminopyrene and sodium nitrite (antiformation) and on the standard mutagen produced from the same reaction (antimutagen). For the seed extract, there was not direct mutagenic either with or without nitrite treatment on both tester strains, and it could interfere the formation of mutagen by decreasing the mutagenic activity. On the other hand, it was found that the seed extract slightly enhance the mutagenic activity of the standard mutagen. In addition, pericarp extract exhibited direct mutagenic activity after being treated with nitrite and increased the mutagenic activity on the formation of standard mutagen. However, the antimutagenic activity of the pericarp extract on the standard mutagen obtained from 1-aminopyrene reacted with sodium nitrite on S. typhimurium strains TA98 and TA100 was observed. The present study revealed the different inhibitory mechanisms of Z. limonella seed extract and that of Z. limonella pericarp extract on mutagenic activity of standard mutagen. However, the consumption of fruits from Z. limonella with nitrite or nitrite containing food products should be avoided to prevent the formation of mutagen.
Preparation and antimicrobial activity of caprylic acid emulsion for food coating
Authors:   , Bunyovimonnat Raweewan
Published: September 2023

Antimicrobial food coating is the interesting method for food preservation, especially in fruits and vegetables. Previous studies have been reported that the caprylic acid had the antimicrobial activity against a variety of microorganisms. However, little research has been conducted on the use of caprylic acid in the form of food coatings. Therefore, this study aims to determine the optimum conditions for the caprylic acid emulsion preparation and to evaluate the antimicrobial activity of the emulsion, including the effect of food coatings with caprylic acid emulsion on physical properties and microbial growth inhibition. Emulsions containing 4% w/v caprylic acid (oil) and various concentration of surfactant mixture (polysorbate 80: monocaprylin at 1: 1 weight ratio) were prepared. The response surface methodology, Box-Behnken design, was used to optimize the factors for emulsion preparation which were surfactant concentration, sonication time and amplitude. The study showed that the optimized formula, which had small particle size, high values of zeta potential and low polydispersity index, could be prepared using 3.6% w/v surfactant mixture, sonication time of 120 sec and 30% sonication amplitude. The emulsion had the minimum bactericidal/fungicidal concentration at 0.25% w/v caprylic acid and was stable after storage at 30 ± 2 °C and 40 ± 2 °C, relative humidity (RH) 75 ± 5% for 28 days. Food coating formula contained caprylic acid (0.25% w/v) emulsion using 2% w/v alginate as a film-forming compound with 1.5% w/v glycerol and 2% w/v calcium chloride. Food sample (pitahaya pieces) coated with caprylic acid emulsion stored in the refrigerator for 12 days had statistically insignificant (p>0.05) change in color, weight loss and firmness compared with the uncoated food, whereas the growth of bacteria and fungi of coated samples was significantly reduced (p<0.0001). In conclusion, the caprylic acid emulsion could be used as antimicrobial food coating. Ongoing research should be conducted on sensory evaluation for further development in food preservation.
Carbohydrate content of the medications for epileptic children treated with ketogenic diet at King Chulalongkorn memorial hospital
Authors:   , Sawangrit Thanarat
Published: September 2023

The purposes of this study were to establish a database of the carbohydrate content of medications and investigate carbohydrate content of medications in epileptic children treated with ketogenic diet (KD) at King Chulalongkorn Memorial Hospital. One hundred sixty-nine KD order forms in 3 events (KD initiation, follow-up visit, and hospital re-admission) for epileptic children whose aged younger than 18 years old during 2009-2017 were selected. Clinical and nutritional data were obtained from medical records and KD order forms from the pediatric nutrition unit. The study showed that oral liquid dosage forms had the highest carbohydrate content in the formulations as 0.52 (0.13-1.78) g/dosage unit. In the event of hospital re-admission, children were at risk of excessively received carbohydrate content of medications because of the increased number of medications for treating illnesses. However, there was no significant difference between carbohydrate content in the prescribed diet and carbohydrate content in the prescribed diet plus carbohydrates from medications in 3 events (p>0.05). Likewise, the difference between fat: non-fat gram ratio in the prescribed diet and fat: non-fat gram ratio in the prescribed diet plus carbohydrates from medications in 3 events were not significant (p>0.05). The result showed that seizure frequency was positively correlated with number of anti-epileptic drugs (r=0.365, p=0.021). However, no significant correlation was found between seizure frequency and carbohydrate content in the diet as prescribed plus carbohydrates from medications (p=0.462). This study demonstrated that medications in oral liquid dosage forms contained high carbohydrate content which may impact ketosis status; therefore, such dosage forms should be avoided in epileptic children treated with KD. Children should be closely monitored urine ketone, serum ketone level, and seizure frequency.
Étude de l’espace dans les contes de fées de madame d’aulnoy : de l’enfermement à l’émancipation
Authors:   , Kanchanobhas Vanichcha
Published: September 2023

Dans les contes de fées de Mme d’Aulnoy, l’espace est étroitement lié à la sexualité. L’Éros constitue un mobile capital qui pousse un personnage à en enfermer un autre. La prison affecte la sexualité du prisonnier. L’évasion de la prison relève de la question de la vie et de la mort. Une tentative ratée est punie : le châtiment va de la déshumanisation au trépas. Le Thanatos constitue le seul moyen qui permet l’émancipation. S’évader du clos et se retrouver dans l’ouvert permettent une libération sexuelle, et aussi une maturité pleinement développée. Néanmoins, certains désirs sexuels tendent plutôt à s’épanouir dans l’espace fermé. Les personnages de Mme d’Aulnoy sont ainsi complexes et contradictoires, ayant des aspirations le plus souvent opposées. Ni le clos ni l’ouvert ne les comblent : enfermés, ils cherchent la liberté dans l’espace ouvert ; libres, ils aspirent à la protection dans l’espace fermé. Une telle complexité et une telle contradiction sont en fin de compte le reflet de tous les temps, ce qui souligne l’universalité de l’œuvre de notre conteuse.
Seismic Characteristics Of Paleo-Pockmarks At Great South Basin, New Zealand
Authors:   , Karaket Arunee
Published: September 2023

Paleo-pockmarks and present-day pockmarks are founded in several varieties both onshore and offshore worldwide. These features can be used as an indicator of fluid flow process which expulses through an unconsolidated sediment within the basin. The Great South Basin, New Zealand is one of the basins that paleo-pockmarks are observed covering the southeast offshore of South Island at around 1.5 s (TWT) depth beneath the surface. This study aims to identify seismic characteristics of paleo-pockmarks in the Great South Basin and predict the possible fluid origins and their mechanism. The numerous paleo-pockmarks are identified and imaged by using 3D seismic interpretation. Paleo-pockmarks in the study area are observed on the fine-grained sedimentary succession of middle Eocene as known Laing formation. The paleo-pockmark distribution is aligned from the southwest toward northeast direction coincident with fan shaped geometry. Paleo-pockmark area are divided within 3 major zones to study morphology and density of paleo-pockmarks. There are zone 1 located in the proximal fan, zone 2 located in the middle fan, and zone 3 located in the distal fan. The 94 paleo-pockmark samples are randomly chosen from 3 zones for size measurement. Paleo-pockmarks in the study area are identified as “normal pockmark” with sub-round to round on the top view, V-shape and U-shape in profile view. Their size ranges from 131 to 481 m in diameter and 15 to 45 ms (TWT) in depth. Paleo-pockmarks are observed to have high density around 13.4 paleo-pockmarks per a square kilometer at the central part of the study area (zone B). Furthermore, location distribution of paleo-pockmarks is interpreted to be caused by two possible fluid origins. Microbial methane is the main fluid origins which generate more widespread middle Eocene paleo-pockmarks in low temperature condition. While pore water in compacted fine-grained sedimentary layers, including late Cretaceous to early Paleocene Wickcliffe formation and early to middle Eocene Laing formation, are possible to be one of the fluid sources of paleo-pockmarks in the study area as well.
Aftershock analysis in the mainland Southeast Asia
Authors:   , Traitangwong Premwadee
Published: September 2023

In this study, the characteristics of the aftershock in the mainland Southeast Asia (MSEA) were investigated using the several seismological techniques, i.e., i) the Gutenberg-Richter relationship (G-R relationship) ii) the modified Omori’s law iii) the Bath’s law and iv) the fractal dimension. After declustering, 1,697 clusters during 1985-2017, which represent the aftershocks occurring after mainshock were investigated in 13 seismic source zones recognized in the MSEA. According to the Bath’s law, the maximum magnitude of the aftershock depends on the magnitude of the mainshock, with the difference value between 0.4-2.5. In the intraplate zone, it is less than in the interplate zone, especially in Western Thailand and Southern Thailand zones (0.4-0.7). Next, the decay rate of the aftershock and the number of aftershocks based on the modified Omori’s law are positive relation with the magnitude of mainshock. After that the fractal dimension (Dc) for 13 zones are approximately 2.0, which means the distribution of the aftershocks in the MSEA are distributed into two-dimensional fault plane.

In addition, for the spatial investigation, the b values of aftershock from the G-R relationship are in range of 0.8-1.8 that different from the mainshock. While for the temporal investigation, it is confirmed that the beginning of the mainshock is high stress, and then gradually release the accumulated stress. Finally, the relationship of the Dc and b values is positive correction as well as the relationship of the Dc values and a-b ratios.
Effectiveness of Ammonium Ion in Low salinity Waterflooding in Shaly-sandstone Reservoir
Authors:   , Quoc Hung
Published: September 2023

Low Salinity Waterflooding (LSWF) has been intensively studied worldwide as it is a low-cost technique. By injecting water with very low salinity compared to formation water in the reservoir, the method changes equilibrium between rock surface, oil and surrounding water, causing wettability alteration through Multi-component Ion Exchange (MIE) mechanism. In this study, ammonium ion is added into low salinity water to facilitate the MIE mechanism in shaly-sandstones reservoir. Experiments are performed with shaly-sandstone rock as it contains both calcium and magnesium ions as part of clays and ammonium ion can express its potential by triggering MIE mechanism. Stirring test, spontaneous imbibition test and coreflooding test are performed to research the effects of ammonium ion in low salinity water that could generate positive results in oil recovery mechanism.

From the experiments, it can be observed that ammonium ion is a foreign ion that can be easily adsorbed onto rock surface to displace divalent ions. Nevertheless, the ammonium ion itself tends to displace more calcium ion than magnesium ion on clay surface. Adding potassium ion into ammonium ion solution results in shifting from favorability of calcium ion dissolution toward magnesium ion dissolution. Since magnesium ion creates stronger bond compared to calcium ion, ammonium ion is therefore considered to be superior to potassium ion in oil recovery mechanism. The results from imbibition and coreflood test confirms that low salinity waterflooding in shaly-sandstone can be accomplished by the used on ammonium ion. However, ammonium ion should be prepared to favor the dissolution of calcium ion since oil that is attached through calcium ion is easier to be recovered compared to that of the dissolution of magnesium ion.

In this study, the solution of pure ammonium chloride and mixture of ammonium-calcium-sodium ion at the ratio of 40-20-40 show good potential in enhancing oil recovery. Nevertheless, the case of ammonium-calcium-sodium ion at the ratio of 40-20-40 might be suitable for the existing oilfield since sodium can be mixed with the water formulation at high portion and fresh water demand can be minimized. From the conditions tested in this experiment, oil recovery factor from the use of ammonium ion can be increased up to 26 percent.
Pre-feasibility study of silica sand processing plant in Sihanoukville province, Cambodia
Authors:   , Ros Sochea
Published: September 2023

In this study was presented the pre-feasibility study of silica sand processing plant in Sihanoukville province. The resources approximately 8,750,000 tons, would be a high potential deposit for the glass industry. In this study focuses on the characteristics of the silica sand, methodology to remove the impurities which contained high Fe2O3, Al2O3 and another major oxide element, and economic evaluation technique. To identification of silica sand which used sieve analysis, Frantz isodynamic magnetic separator following by electrical microscope, XRD, and XRF. 

Therefore, to upgrade the quality of silica sand, which is using Shaking Table, Wet High-Intensity Magnetic Separator, and Reverse Flotation. The result of original sample (SiO2 = 94.61 Wt.%), Fe2O3 = 0.18 Wt.%, Al2O3 = 2.50 Wt.% on an average. In the Shaking table, WHIMS, and Reverse flotation SiO2 = 96.68 Wt.% with 0.10 Wt.% of iron oxides, 98.80 Wt.% with 0.057 Wt.% of Fe­2O3, and 99.14 Wt.% with 0.021 Wt.% of Fe2O3 respectively. Moreover, the financial analysis result which including NPV = 754,615,135.13 baht, WACC = 13.64%, Discounted rate = 13%, IRR = 69.64%, and MIRR = 33.47% within Discounted payback period 1.44 years.
Ore reserves estimation of the Nam Nga coal deposit, Lao PDR, using geostatistical method
Authors:   , Bliachongvang Tongvang
Published: September 2023

This research study focuses on estimating the coal deposit quantity and qualities as CV and AC at Nam Nga coal deposit, Lao PDR using OK and SGS geostatistical methods. A total of 295 assays data from 51 exploration drill holes collected from LID Company were used. The results reveal that OK produces geological resource of 2.2 MT with an average CV of 3,733 kcal/kg and an average AC of 48.68 %. The mineable reserve computed from OK’s ultimate pit design and pit adjustment are 0.55 MT. The OK method produces 9.32 MT of wastes, yielding a stripping ratio of 10.4:1. The SGS method produces 2.2 MT of geological resource with an average CV of 3,769 kcal/kg, and an average AC of 46 %. The SGS’s ultimate pit design and pit adjustment generate 0.54 MT of mineable reserve. The SGS generates wastes 9.5 MT, yielding a stripping ratio of 10.1:1.

In comparison, the OK and SGS produce the very similar results for coal grades estimation, mineable reserve, and stripping ratio calculation. However, OK generates smoother maps when most of the estimated values moving toward the mean value. SGS method is better in preserving a local variation, as can be seen in the overall simulated variance closed to the original data variance. And SGS also provides a multiple realization maps which bring a benefit for accessing the risk involved.
The dislodgement of the sponge head of novel Thai-produced sponge brushes
Authors:   , Meechumna Nawachat
Published: September 2023

Objective. To perform an in vitro investigation on the dislodgement of sponge head of different manufactured sponge brushes (Sakura shape, Sunstar BUTLER, Japan, and 4 novel Thai-produced sponge brushes; combination of two shapes (round and Leelawadee) and two textures (soft and hard), King Dental Innovation Foundation; KDIF , Thailand. Methods. In order to evaluate the dislodgement of sponge head, strength test measurement was performed according to ISO 20126:2012(E). Five types of polyurethane foam were characterized using Fourier transform infrared spectroscopy (FTIR). The density of the foam was evaluated as the weight of foam in the air per unit volume of a specimen. Specimens were weighed. The volume was analyzed by Micro-CT. Finally, the mean “Force (N)/Density (kg/m3)” data of each group was calculated and investigated. Results. The density of Thai-produced yellow foam, Thai-produced white foam and Japan-produced are as followings; 28.56, 16.17 and 48.53 kg m-3 respectively. The “Force/Density” value of each group were calculated. The comparative analysis revealed that the five types of sponge-foam have different densities. Sakura shape sponge head exhibited significantly more difficult to be dislodged, comparing to other four sponge heads. With the same density, round shape exhibited significantly more difficult to be dislodged, comparing to the Leelawadee shape. Conclusion. The yellow sponge head in the cross-section round shape had the most resistance to dislodgement, compared to four novel Thai-produced sponge brushes because of the higher density of foam results in the higher strength. By the way, fatigue resistance and handle impact test should be conducted for assessing the physical properties of handles. Biological hazards should be the greatest concern to assessing possible biological hazards.
Establishment of an in vitro system to screen for substances to improve osteogenesis imperfecta osteoblasts’ functions
Authors:   , Udomchaiprasertkul Wandee
Published: September 2023

Background: Osteogenesis imperfecta (OI) is a heritable bone disorder caused mainly by dominant mutations in genes encoding collagen-related proteins which are COL1A1 and COL1A2. Genotype-phenotype correlation has some discrepancies which lead to the difficult prediction of the clinical outcome of OI patients. We identified a child with dentinogenesis imperfecta (DI) and OI who was homozygous for c.1009G>A (p.G337S) mutation in COL1A2. Her parents were heterozygous for the mutation and had only DI. This family provides the opportunity to explore the biochemical changes which are different between the homozygous with DI and OI and the heterozygous with DI only. Methods: We established patients-specific induced pluripotent stem cells (iPSCs) from the trio to use as an in vitro system to screen for biochemical substances. They were used to study the expression of the osteogenic marker genes (COL1A1, COL1A2, SPP1, OCN, ALP) and their products along the time course of osteoblast differentiation. Results: We successfully generated patient-specific iPSCs from the trio. They all showed the characteristic features of iPSCs. We then differentiated them to mesenchymal stem cells (MSCs) and osteoblasts. Their osteoblasts showed various defective expression of the osteogenic markers and calcium mineralization. Interestingly, osteopontin was absent in iPSCs-derived osteoblasts of patients with OI, while it was significantly lower in those with DI-only compared to an unaffected control. In addition, osteocalcin was significantly lower in those with OI compared to DI-only and an unaffected control. Conclusion: Levels of osteopontin and osteocalcin in iPSCs-derived MSC of patients with OI were significantly low during osteoblasts differentiation. These cells could be used to screen for substances which can increase osteopontin and osteocalcin.
Decolorization of Reactive Black 5 using Soil Bacterial Consortium under a Combined Dynamic and Static Condition
Authors:   , Sari Dita
Published: September 2023

Decolorization of Reactive Black 5 (RB-5) dye by isolated soil bacterial consortium had been conducted in this research. This study aims to determine the effect of operating conditions and kinetics of RB-5 decolorization by single strains and the consortium. Bacterial strains capable of RB-5 decolorization were isolated and identified as Micrococcus sp., Janibacter sp. and Rhodococcus sp. The RB-5 synthetic wastewater was used in the experiments with five days of incubation time. The studied conditions include combinations of shaking (dynamic) and static period of incubation, bacterial concentration, initial pH, temperature, and initial dye concentration. The results showed that the combined dynamic and static condition was important to RB-5 decolorization by the isolated bacteria. The decolorization with highest efficiency for all cultures was obtained at pH 7 with 2-day shaking period continued with 3-day static period for single strains and 1-day continued with 4-day for the consortium. The highest efficiency was given by Janibacter sp. (94.8% at 100 mg/L), which exhibited a good performance up to pH 11. All the decolorizations of RB-5 by single strains followed the first-order kinetics (4/-5 concentrations of 200 to 1,000 mg/L) but this was not observed with the consortium. Even though the decolorization efficiency of the consortium (88%) was not as high as the standalone Janibacter sp., the shaking period could be reduced from 2 days to 1 day without losing high ability to decolorize at pH 11. This suggests that working with consortium could give a benefit of reducing the aeration period compared to working with single strain, which will be useful for wastewater treatment application.
Diesel removal efficiency in soil washing process by mixed solution of nonionic surfactant and biosurfactant
Authors:   , Boonyathai Pajaree
Published: September 2023

In this study, Tween 80 and three biosurfactant (Rhamnolipid, Saponin and Lipopeptide) were mixed to formulate the appropriate surfactant solution for diesel removal from contaminated soil by washing process. The mixed surfactant system was fixed at 5% w/v of active surfactants concentration in total with different mass ratio of Tween 80 to biosurfactant at 9:1, 8:2 and 7:3 of total concentration. The critical micelle concentration (CMC) of various ratio surfactant mixtures and their interfacial tension (IFT) with diesel were determined and compared with their individual surfactant. The results illustrate that mixed Tween and Lipopeptide at 9:1 mass ratio had the lowest IFT with 10 times lower than its individual surfactants. All mixed surfactant formulations showed the lower CMC than the individual biosurfactant, but still higher than that of Tween 80. The selected mixture of Tween 80 and Lipopeptide was investigated the influence of surfactant on TW sorption and diesel removal efficiency on various of soil texture. The mixed surfactant decreased the sorption of Tween 80 on soil compared to the system of individual TW because of the effect of charge repulsive between negative charge on mixed micelle and soil surface. The diesel removal by mixed Tween 80 and Lipopeptide was slightly lower than that of the individual TW. This might be due to the DI rinsing step, which increased the total diesel removal efficiency of single Tween 80. Moreover, the results displayed that the concentration of mixed Tween 80 and Lipopeptide could be decreased to 3% w/v (2.7% w/v of Tween 80 and 0.3% of Lipopeptide) with negligible loss of diesel removal efficiency. Besides the concentration of mixed surfactant, liquid-solid ratio (L-S ratio) and centrifuge speed were evaluated the optimal level in diesel removal efficiency by central composite rotatable design (CCRD). The results showed that surfactant concentration and L-S ratio significantly influenced on diesel removal efficiency. The highest diesel removal efficiency was 79.90 %. The predicted optimal level of surfactant concentration was approximately 3% w/v. For L-S ratio and centrifuge speed, the model suggests that these two factors could be increased for improving the diesel removal efficiency in the further study.
Application of reduced graphene oxide/ natural rubber composite for petroleum removal in sea water
Authors:   , Songsaeng Siripak
Published: September 2023

In this study, the natural rubber (NR) composite foam was prepared to enhance oil adsorption performance of NR foam. The reduced graphene oxide (rGO) was synthesized from graphite waste by oxidation and reduction processes. In the oxidation step, different oxidation conditions (thermal-sonication and stirring-sonication) were studied in order to achieve the highest interlayer spacing in graphite structure. Then, the reduction was carried out using L-ascorbic acid (L-AA) as a reducing agent. Furthermore, morphology and surface properties of the synthesized rGO were investigated. To prepare the NR composite foams, NR latex was mixed with various contents of rGO (0.25, 0.5, 1.0 and 1.5 parts by weight per hundred part of rubber: phr). The results showed that the amount of rGO affected the morphology and the oil adsorption capacity of  NR composite foams. The optimum amount of rGO in the NR composites foam which exhibited the highest oil adsorption performance was 0.5 phr. The oil adsorption capacity of NG-0.5 for gasohol, kerosene, crude oil, diesel and fuel was 21.50, 19.31, 17.04, 16.53 and 10.09 g g-1, respectively. In addition, the effect of temperature and turbulence on the oil adsorption capacity of the NR composite foams was determined. Three kinetic models, i.e. pseudo-first-order, pseudo-second-order and Elovich equation, were examined. The pseudo-second-order presented the better fit with the experimental data. The Langmuir isotherm was an appropriated model to predict the oil adsorption behavior of the NR composite foams. Finally, reusability feature of the NR composite foams was also studied through fifteen oil adsorption-desorption cycles. The result showed that the NR composite foams could be reused in many times.
Caring for patients with drug use disorders in Yangon region, Myanmar : Socioeconomic and psychological burden and coping strategies
Authors:   , Thein Khin
Published: September 2023

Drug use disorders are considered chronic illnesses, like other severe mental disorders, and caregivers of drug users face a large impact on various aspects of their life. However, there is shortage of research in Myanmar about caregivers’ experiences with caring for patients with drug use disorders. This mixed method study, therefore, aims at exploring the socioeconomic and psychological burden caregivers carry, the coping strategies they employ, as well as the barriers to coping they face. The results of the framework analysis revealed that financial loss, productivity loss, social limitation and negative impact on family members are important dimensions of socioeconomic burden. Sadness, anger, worry, fear and guilt were main psychological distress factors encountered by caregivers of patients with drug use disorders. The strong positive correlation between caregiver stress level and the addiction severity of patients reinforced the qualitative findings. Religious coping, financial coping, acceptance and planning were commonly used coping strategies by the caregivers.  Moreover, perceived stigma towards patients and caregivers was very high and the caregivers received hardly any social and financial support from the government or any other organization in Myanmar. The results of this study show that caring for patients with drug use disorders has devastating effects on caregivers and their families. Therefore, reforming existing drug policy, and strengthening drug abuse prevention and treatment programs and campaigns should be considered a priority.
System dynamics analysis of sugar-sweetened beverage taxing effect on sugar consumption, dental health service utilization and oral health for Thai adults and elderly
Authors:   , Urwannachotima Nipaporn
Published: September 2023

Dental caries is a major oral health problem, particularly among developing countries. Almost half of Thai adults and elderly have at least one untreated dental caries. Dental caries can result in debilitating pain that affects work productivity and even the performance of daily activities. The objectives of this study are to develop system dynamics model addressing the relationship of dental caries, sugar consumption and dental health service utilization of Thai population aged 15 and older; and to estimate the changes of dental caries prevalence when the sugar-sweetened beverage tax is implemented. A multi-sector system dynamics model was developed to consolidate the relationship between the progression of dental caries experience and oral health related behaviors. Four hypothetical policy scenarios were simulated to investigate potential points of intervention to improve dental caries status in the population. The main scenario was the implementation of sugar-sweetened beverage tax.  The study shows that the sugar-sweetened beverage tax can produce the reduction of sugar consumption compared to the base-case scenario without the policy for both short-run (3.2% for poverty population, and 5.4% for non-poverty population) and long-run (5.2% for poverty population, and 7.5% for non-poverty population). However, the impact of the sugar-sweetened beverage tax on reduction of dental caries prevalence is not pronounced.  The model also shows that the combined tax policy with other non-tariff intervention such as health promotion program and the encouragement of reformulation in sugar-sweetened beverages could provide the most benefit on reduction of sugar consumption and dental caries prevalence.  In addition, changes in oral health are evident in populations at high risk for dental caries. This study is an example of system dynamics model use for providing policy makers with additional insights to support their oral health policy planning for Thai population.
Periodic-review order policy for a two-echelon inventory problem with seasonal demand
Authors:   , Sakulsom Noppadon
Published: September 2023

This dissertation presents methodologies to determine ordering policies for a 2-echelon inventory system with multiple replenishing modes under seasonal demand.  The system operates on periodic review basis using reorder point and order-up-to point or (R,s,S).  An Echelon stock concept is applied where each location makes decisions on its own inventory information and the information of all locations downstream.  We decompose a problem into two phases and propose a methodology based on mixed-integer programming models to determine ordering policies for a system with one replenishing mode.  Then, another methodology based on the genetic algorithm and binary search is developed to solve the problem with shorter computational time.  The later methodology can solve problem with 97.49% on average less computational time in the first phase and 95.99% on average less time in the second phase.  Afterwards, a problem is extended to a system with a regular replenishing mode as a main replenishing mode and two special modes to prevent stockouts.  Under seasonal demand, special modes could have either a static policy which applies one policy on every period or a dynamic policy which applies a different policy for each period in the demand cycle.  Special replenishing modes can eliminate the periods with unsatisfied service level with slightly higher holding cost.  A dynamic policy tends to give smaller number of special orders.  However, in case of high deviation demand and short demand cycle, for ease of use, the static policy can substitute the dynamic policy.
Effects of 4,5,4'-trihydroxy-3,3'-dimethoxybibenzyl from Dendrobium ellipsophyllum on induction of apoptosis and inhibition of cancer stem-like cells in human lung cancer H460 cells
Authors:   , Hlosrichok Anirut
Published: September 2023

Failure of current chemotherapeutic drugs leads to the recurrence of tumors and increased mortality in lung cancer patients. This study investigated 4,5,4'-trihydroxy-3,3'-dimethoxybibenzyl (TDB), a bibenzyl extracted from Dendrobium ellipsophyllum Tang and Wang as a novel anticancer agent for lung cancer. Selective anticancer activity of TDB against human lung cancer cells was demonstrated with a high half maximal inhibitory concentration (IC50) approximately > 300 µM in dermal papilla cells, while IC50 in human lung cancer H460 cells was approximately 100 ± 5.18 µM.  Flow cytometry confirmed that TDB (50 µM) treatment for 24 h, caused significant early and late apoptosis but not necrosis in H460 cells. The up-regulation of p53, a tumor-suppressor protein, was observed in human lung cancer cells treated with 10-50 µM of TDB. The mechanism for apoptosis was attributed to p53 activation, which was related to up-regulation of pro-apoptotic Bax, reduction of anti-apoptosis Bcl-2 and Mcl-1 proteins and suppression on protein kinase B (Akt) survival pathway. Another possible mechanism involved in TDB-induced apoptosis in H460 cells was the modulation of reactive oxygen species (ROS), as intracellular ROS level was decreased by TDB (50 µM) treatment for 3-6 h as detected by 2',7'-dichlorofluorescein diacetate (DCFH2-DA) fluorescent probe. Moreover, Hoechst33342 staining showed that apoptosis was significantly decreased in H460 cells incubated with 100 µM of hydrogen peroxide (H2O2) for 30 min prior exposure to TDB (50 µM) compared with the cells only treated with TDB. Additionally, TDB inhibited cancer stem cell (CSC)-like characteristics in H460 cells as evidenced in spheroid assay and flow cytometry analysis, whereby CSCs, CD133-positive cells markedly decreased after TDB treatment. TDB caused a decrease in protein levels of the stemness-related transcription factors; Nanog and Sox2 while there was no alteration of Oct4. There was the reduction of related regulator proteins, β-catenin. In conclusion, TDB extracted from D. ellipsophyllum demonstrated stemness suppression and selective apoptosis induction via intracellular ROS reduction in human lung cancer cells. The results obtained from this study strengthen the potential development of TDB as an anticancer compound with a favorable safety profile.
Thai civil partnership is the new marriage inequality : queer critiques on the discourses in the civil partnership bill of state activism towards marriage ‘equality’
Authors:   , Wongprasert Thanita
Published: September 2023

With an equal access to legal registration becoming the international mainstream development agenda and movement of 21st century, Thailand proposed a civil partnership bill developed by the Rights and Liberties Protection Department in 2018. Although the initiative seems promisingly progressive, the drafting, legal product and outcomes that the bill promises to bring lay vigorous ground of criticisms. This thesis is the first English-language academic work that uniquely integrates theoretical outlook and arguments of queer theory where Foucauldian discourse analysis is the key concept applied to critique the discourses codified in the bill. This thesis aims to analyze how Thai discourse of marriage affects state activism of marriage equality through the proposal of controversial civil partnership and argue how it is a new marriage inequality. This thesis presents key findings derived from secondary sources, content analysis of the bill, interviews with key actors, participation in relevant activities and events and insights from the author as an activist. The discourse of marriage in Thailand is more social and cultural than legal where witnessed ceremony without registration with state is regarded as recognition. Interacting with foreign influences, the civil partnership as a new registration system was proposed to make marriage more gender-inclusive and arguably equal, however the criticisms prove otherwise. Thai movement of marriage equality faces internal complexity among the civil society and state authorities. This paper concludes that beyond the limitation of rights, the civil partnership bill is a new marriage inequality. The oppressive institution of marriage whose discourse is monopolized by state is used as a tool to control and discipline Thai LGBTI couples. The discriminative civil partnership act normalizes and compromises the needs of the community with statist interest of state, enabling the reproduction and idealization of state-approved norms and expectations.
Ulaanbaatar's Ger District Residents: An analysis of development challenges and structural violence
Authors:   , Jenkins Timothy
Published: September 2023

This study investigates and researches the impact of the Government’s policy of putting the ‘economy first’ by analyzing the situation through the lens of Johan Galtung’s concept of Structural Violence. The research answers the question: How does structural violence occur in the ger districts of Ulaanbaatar under the current development challenges?

In the 1990’s, after the fall of communism, the IMF and the World Bank, along with some leading political figures within the Government of Mongolia, pushed forward with their plans to bring the free market to Mongolia. The World Bank and the IMF introduced the shock-therapy approach with the aim of quickly integrating Mongolia into the global supply chain. Massive layoffs were instituted within the government and nearly all of the state-owned industries were privatized. This resulted in mass inflation, job loss, and increases in poverty. The consequences of shock therapy reverberated throughout the social landscape for decades. Today, the Government continues to heed the advice of the IMF and the World Bank by focusing on the economy and gaining the trust of foreign investors and other key partners. As a result, the economy continues to be put ahead of social issues and services, with limited consultation with those most effected: the herding populous. What this means is that a pattern of injustice has been solidified within some structures so much so that the lowest-ranking actors, in this case the rural migrants now living in the ger districts of Ulaanbaatar, were deprived not only of their respective potential, but undeniably below subsistence minimum. These policies were compounded in 2017 when the Government received a bailout from the IMF. As a result, basic social services were again slashed, and taxes rose across the country to meet the demands for the loans.

This paper is particularly focused on extracting data via interviews of internal migrants originally from rural communities now living in Ulaanbaatar, Mongolia. To support these findings, an analysis of civil society, UN reports and in-depth interviews have been conducted, as well as a review of public statements by government officials. The research has found evidence of the structural violence against migrants that have settled in the capital city who were forced to abandon their livelihoods in the countryside and retreat to the ger districts of Ulaanbaatar.

This paper concludes that citizens living in the ger districts are the victims of structural violence, and that this violence takes the form of higher morbidity and mortality rates as a direct result of air pollution, limited access to basic social services, and unreasonable distances to healthcare facilities. The circumstances for this inequality are the direct result of the World Bank’s and the IMF’s “shock therapy” strategy and is further perpetuated by poor governance and the exclusion of poor communities from meaningful civic participation.
Impact of Trade and FDI Openness on Wages in the Manufacturing Sector in China
Authors:   , Chen Qianyi
Published: September 2023

The purpose of this study is to examine the impact of trade openness and foreign direct investment (FDI) on wages in China using a panel data set of 27 manufacturing sectors over the period of 2001 to 2016. The effects are separated into three groups: total industries, capital-intensive industries and labor-intensive industries.

First, by comparing the determinants of three groups of industries, it shows that the impact of trade openness on wages only significant and positive in labor-intensive industries while the impact of FDI on wages is significantly positive in both capital-intensive industries and labor-intensive industries. Second, in the case of total industries, trade openness and FDI are insignificant to wages. Labor productivity, research and development (R&D) expenditure, the proportion of skilled workers to total skilled and unskilled worker are significantly positive to wages. In contrast, the proportion of female workers to total employment and the proportion of state-owned enterprises to total enterprises are significantly negative to wages. Third, for capital-intensive industries, the impact of trade openness on wages is insignificant while the impact of FDI is significantly positive on wages. Moreover, labor productivity, R&D expenditure and the proportion of skilled workers to total skilled and unskilled workers are significantly positive to wages. Finally, for labor-intensive industries, the impact of trade openness and FDI are both significantly positive to wages. Furthermore, labor productivity, R&D expenditure and the proportion of skilled workers to total skilled and unskilled workers are significantly positive to wages. However, the proportion of female workers to total employment and the proportion of state-owned enterprises to total enterprises are significantly negative to wages.

Last but not least, the results imply that the benefits of trade and investment policies of China on industrial wages should be made more inclusive to all types of industries, either capital or labor-intensive industries.
Assessing Impacts of FTA in Thailand with Special Emphasis on Trade Creation and Trade Diversion
Authors:   , Charoenchang Sawasdee
Published: September 2023

This paper uses ex-post gravity analysis to examine whether Thailand’s 12 effective free trade agreements cause trade creation or trade diversion effect. The sample of the study covers 43 countries over the period of 1991-2016.

The model is specified with the aim to obtain unbiased estimates of three FTA dummy variables, representing trades within and outside the trade blocs. This study is able to analyze only 7 out of 12 total FTAs due to multicollinearity problem.

The results of this study show that AFTA has trade creation effects on international trade of Thailand with little diversion effects on exports. We found pure trade creation in exports and mild import diversion from ACFTA and AJCEP. In general, ASEAN-plus-one agreements have caused trade creation effects to Thailand's exports and some or little import diversion. On the other hand, the results suggest that bilateral free trade agreements have different trade effects. TPCEP causes pure trade creation effects on Thailand's overall trade. Results obtained from ITFTA indicate that the higher trade level from the agreement come from trade diversion effects. Regressions on JTEPA and TCFTA indicate trade contraction effects.

Therefore, this study supports the notion of trade liberalization for Thailand. The policy recommendation to Thai policy maker is that negotiations on further FTAs should be focusing on ASEAN plurilateral agreements, which tend to provide benefits to intra-bloc and extra-bloc countries.