bluuebunny/crossref_metadata_2025 huggingface dataset:
Influential factors of water conservation behaviors in household: a case study of condominiums in Bangkok, Thailand
Authors:   , Sirimungkla Sutida
Published: September 2023

This study aims to investigate water use and water conservation behaviors of people in condominiums in Bangkok, Thailand, and to determine the most influential factor to the behavioral intention, among attitude, social norm, perceived behavioral control (PBC), and information effect. A questionnaire survey of 210 respondents was conducted in Bangkok Metropolitan area between January – April, 2018. Data was analyzed by descriptive statistic to investigate water conservation behaviors and Structural Equation Model (SEM) to examine the determinants of intention to perform the everyday water conservation behaviors and to install water saving devices. The results indicate that two top practices rate related to everyday water conservation behaviors are (1) making sure that the tap not drip and (2) cleaning food scrapes before dish washing. Most of residents have installed dual-flush toilet in their household. Essentially, the SEM result reveal PBC affects significantly on intention to everyday water conservation behaviors. And attitude and information effect have influence to install water saving devices. The results from this study increase an understanding about key factors affecting the motivation of water conservation behaviors. This is helpful to develop effective water demand management strategy and future policy.​
System Dynamics Analysis On Municipal Solid Waste Management Under Flooding : Case Study Bangkok, Thailand
Authors:   , Phonphoton Nuchcha
Published: September 2023

The municipal solid waste management service system has been one of the key service provisions to indicate the sustainability of the city as defined in Sustainable Development Goals - SDGs #11. Complex linkages of stock and flow within the system are impacted by waste quantities and spatial characteristics. The complex characteristics make it difficult to design a sustainable management system, particularly in case of a disaster. Flooding is a major natural disaster in many regions of the world and poses a challenge as an external disturbance that can affect any part of the waste management system. Flood mitigation plans are gravely important for mitigating the impact during crisis situation for communities to face no disruption of the waste management service. 

The present research has applied the concept of system dynamics (SD) to understand and evaluate flood impacts on waste management system. The SD modelling approach has been designed to investigate management patterns of the system and evaluate the impacts of flooding on the waste management service in Bangkok, Thailand. The model illustrates waste generation trends and collection and transfer network patterns to predict potential flood-affected areas. The research analyzed different flooding scenarios and evaluated their potential impact. There are 11 flooding scenarios represented by 11 flood-prone locations. The vulnerable flood-prone area in Bangkae district is the most affected area with the highest accumulated waste amount. The flooding impacts have affected services within and outside the flooded areas to various degrees. The results have been applied to provide the mitigation impact approaches with the multi-criteria decision analysis (MCDA) technique. The flood impacts on municipal solid waste management are classified into 3 situations including: (1) cannot collect wastes from generating sources, (2) cannot transfer wastes to final disposal and 3) cannot collect from sources and transfer wastes to final disposal. The decision support system based on the principles of sustainable development considers the impacting criteria, namely, environment, society, and economic factors.  The truck modification is the first alternative practicable to mitigate impact for all scenarios. Health risk of community and waste separated management are the significant influential criteria to decide the most appropriate approach.

The findings can help to develop an appropriate mitigation management plan for waste management systems during floods to increase the capacity and preparedness toward sustainable cities.
Suppressive effect of crepidatin on stemness of lung cancer cells
Authors:   , Bhummaphan Narumol
Published: September 2023

Cancer stem cells (CSCs) have been perceived as rare populations driving cancer progression, metastasis, and drug resistance in leading cancers. The discovery of new compounds that attenuates CSCs’ properties is crucial for enabling advances in novel therapeutics to limit recurrence. We have reported the CSC-suppressing activity of chrysotoxine and crepidatin, two bibenzyl compounds isolated from Dendrobium pulchellum. Both chrysotoxine and crepidatin displayed suppression in CSC-like phenotypes, as determined in CSC-rich populations and primary CSCs in 3D culture and extreme limiting dilution assay. Individual treatment of chrysotoxine and crepidatin also affected the expression of CSC markers and associated proteins concomitantly decreased known CSCs markers. Importantly, chrysotoxine was shown to suppress active Src/Akt signal and intern depleted Sox2-mediated CSC. Our findings indicate a novel CSC-targeted role of chrysotoxine and its regulation by Src/Akt and Sox2, which may be exploited for the cancer treatment. At the same time, crepidatin showed the highest potency to kill human lung cancer cells. Crepidatin was accomplished as a drug targeting model for lung cancer stem cells. Crepidatin also suppressed CSC-like phenotypes, as determined by CSC-rich populations in 3D culture, clonogenic assay and extreme limiting dilution assay, when compared to cisplatin. The treatment of crepidatin showed dramatic suppression in the CSCs in lung cancer cells, as verified by several CSC phenotype assessments and CSC markers. In addition, crepidatin also suppressed epithelial to mesenchymal transition (EMT) markers and inhibited migratory behavior of CSCs. Importantly, we confirmed the CSC-targeted activity of crepidatin in CSC-rich primary lung cancer cells. The compound dramatically inhibited the formation of tumor spheres of primary lung cancer cells. Finally, we confirmed the effect of crepidatin on the aggressive stem‐like and invasive phenotype in lung cancer cells, where in vivo growth and aggressiveness of crepidatin and cisplatin treated cells were analyzed using the chorioallantoic membrane (CAM) assay. The results revealed that crepidatin significantly reduced tumor growth in lung cancer cells, when compared to nontreated cells, whereas the tumor sizes have been significantly increased in cisplatin treatment. These findings document a novel pharmacological action and establishes the underlying mechanism of chrysotoxine and crepidatin in negatively regulating CSC-like phenotypes and sensitizing resistant cancer cells. Therefore, the findings from this study would provide important insights that facilitate the further investigation and development of the two natural compounds, chrysotoxine and crepidatin, for CSC-targeted approaches.
Comparison of microtensile bond strength of universal adhesives utilizing various application methods: an in vitro study
Authors:   , Jeansuwannagorn Suthatta
Published: September 2023

Purpose: To investigate microtensile bond strength (μTBS) of a conventional three-step etch and rinse, and universal adhesive systems with etch and rinse mode utilizing various application methods at 24 hour and after 6 month water-­storage.

Material and methods: Seventy-­two extracted human third molars were cut to expose a flat dentin surface. Optibond FL (OFL; Kerr, USA), Single Bond Universal (SU; 3M ESPE, USA), Clearfil Universal Bond Quick (CU; Kuraray Noritake Dental Inc., Japan), G-­Premio BOND (GP; GC Corporation, Japan), Prime&Bond Universal (PB; Dentsply, Germany) were used in etch and rinse mode following the manufacturers’ instruction and double application method. Subsequently, composite resins were constructed on prepared dentin and then sectioned into 1x1x8 mm3 stick to be tested after 24 hours and 6 months of water-­storage by microtensile bond strength (μTBS) testing. The data of universal adhesives were analyzed with two-­way ANOVA (p = 0.05). Additionally, the μTBS values were obtained and analyzed with one-­way ANOVA followed by a Tukey Post Hoc test and a Pair T-­test.

Results: The µTBS of universal adhesives were not significantly increased when using double application method compared to manufactures’ instruction at 24 hr (p = 0.652) and after 6 month water storage (p = 0.173). In contrast, kind of adhesives had statistically significant influence on µTBS at 24 hr (p < 0.001) and after 6 month water storage (p < 0.001). Optibond FL, Single Bond Universal Adhesive when applied in double application methods, G-Premio BOND when following the manufacturer’s instruction, and appling in double application method had statistically significantly decreased µTBS after 6 month water-storage. 

Conclusions: Double application of universal adhesives did not improve the bond strength of tested universal adhesives at 24 hours and after 6 months of water storage. Single Bond Universal used following manufacturer’s instruction, Clearfil Universal Bond Quick and Prime&Bond Universal used both following manufacturer’s instruction and modified double application method, had stable dentin microtensile bond strength, while Optibond FL and G-Premio Bond used both techniques had deceased bond strength after 6 months of water storage.
The influence of geological structure on stratigraphic development during multiphase rifting in the Songkhla basin, Gulf of Thailand
Authors:   , Phoosongsee Jidapa
Published: September 2023

The Cenozoic N-S trending Songkhla rift basin, located in the southwest Gulf of Thailand, was developed as a predominantly orthogonal extended half graben structure. The half graben is controlled by a boundary fault zone on the western side of the basin, which forms a series of N-S to NNE-SSW, east-dipping normal faults. The rift spans two phases of rifting; the Eocene-Oligocene and the Oligocene-Miocene phases, the late syn-rift to post-rift transition occurred from the late Early Miocene to Middle Miocene. The main clastic hydrocarbon reservoirs in the basin are located in the Early Miocene to Middle Miocene section. These reservoirs are predominantly fluvial channels with complex lateral and vertical geometries and distributions particularly as point bars, overbank deposits, and sand- or mud-filled channels. This study characterizes the reservoir architecture and depositional environment of the Songkhla Basin from the late syn-rift to post-rift by integrating the seismic attributes (RMS, similarity, and spectral decomposition), well log interpretations, and well biostratigraphic data. Two distinctive channel characteristics and patterns were interpreted: (A) N-S oriented meandering channel complexes, aligned sub-parallel to the western boundary faults, developed during the late syn-rift (upper Early Miocene) and (B) NE-SW oriented long, narrow fluvial channels with tidal and marine influence, developed in the post-rift phase I (Middle Miocene). These channel orientations reflect changes in the basin architecture passing from the late syn-rift stage to the post-rift. Syn-rift channel orientation was controlled by topography created by motion on the western boundary fault system, while the post-rift the channel orientations were affected by mild inversion on the boundary fault system and thermal subsidence, which resulted in an eastwards shift in the basin depocentre towards the flexural margin.
Effects of Monovalent Ions on Low Salinity Waterflooding in Shaly-sandstone Reservoir
Authors:   , Yomchan Ativish
Published: September 2023

Multi-component Ion Exchange (MIE) was proved to be a major mechanism occurred during Low Salinity Waterflooding (LSWF). Reduction of both total salinity and concentration of divalent ions of injected water together with a presence of monovalent ion results in dissolution of divalent ions linking between rock surface and oil. As a consequence, oil is liberated from rock surface.

This study aims to study effects of monovalent ions in MIE mechanism. Stirring test is performed and results show that ion with less hydration radius tends to be more active in MIE; hence, potassium ion and cesium ion illustrate potential in oil recovery mechanism. Then, the best three water formulations can be selected to perform imbibition and coreflood tests and both tests show results in the same direction. Pure cesium ion is very fast in MIE mechanism while pure potassium ion with a few water molecules can also function well in oil recovery. However, its mobility is less than cesium ion. The combination of cesium-sodium-calcium at 20-40-40 tends to be similar results of pure potassium ion. In comparision, Pure cesium ion is the best water formulation enhacing recovery factor up to 0.26. However, complexometric titration result shows remarkable contrast to the stirring test that both cesium ion and potassium ion tend to displace magnesium ion better than calcium ion. In conslusion, this study has already proved the theory regarding the hydrate of monovalent ion.
PM10 and PM2.5 concentrations in Bangkok over 10 years and implications for air quality
Authors:   , Thongthammachart Tin
Published: September 2023

Atmospheric particulate matter particles with a diameter less than 10 micron (PM10) and less than 2.5 micron (PM2.5) have been adverse human health effect. Ambient air pollution data in Central Business District (CBD) of Bangkok monitored by Pollution Control Department and Bangkok Metropolitan Administration were collected over ten years in Bangkok from 2008 to 2017. Trend of the particulate matter concentrations data were investigated over ten year for implications of activities related to air pollution. Daily average air pollution data between year 2015 and year 2017 were used as the dependent variables to develop mathematic models with multiple linear regression (MLR) technique for forecasting PM2.5 concentrations in non-monitored areas. The predicted values of PM2.5 concentrations were validated by various statistical performance indicators. The Q-Q plots of the measured and predicted values of both selected ambient monitoring data and roadside monitoring data had significant correlations, with R2= 0.88 and 0.96, respectively. The non-carcinogenic health risk assessment of PM10 and PM2.5 was quantified as the hazard quotient (HQ) from both the measured and predicted data. The risk areas and HQ were compared using the Inverse Distance Weighting (IDW) interpolation technique and illustrated as GIS-based maps.  The highest HQ value was discovered in the southern area of the CBD. The risk area could be used for greater precaution propose of public health awareness.
Improving Raw Materials Warehouse Utilization and Efficiency in a Haircare Manufacturer
Authors:   , Paveenchana Chariya
Published: September 2023

This study aims to improve the capacity, efficiency, and utilization of raw materials warehouse in a case study of haircare manufacturer in Thailand. At the same time, it is our goal to save the storage cost of finished products at the external public warehouse by locating some of the finished products at this internal raw materials warehouse. The key methodologies used to improve the current raw materials warehouse are removing obsolete materials from the warehouse, regrouping materials according to types, sizes, and turnover rates, reallocating space for each group of materials, considering beam height adjustment, and reassigning the location for each group of materials. The results show that after these methodologies were applied, the capacity of the raw materials warehouse can be increased by 12.65%, picking distance can be reduced by 52% compared to the current situation and the utilization is more balanced throughout the warehouse. Furthermore, 324 locations are available for storing some finished products at the raw materials warehouse which can help to save cost at the external warehouse by 264,000 THB per year. In addition, implementation plans and analysis tools are created in order to navigate the case study company on how to turn improving plans as recommended in this research to actual implementation so that efficiency of warehouse can be increased.
Defect Reduction In Manufacturing Process Of In-Mold Decoration Of Injection Molded Components
Authors:   , Supapan Jintra
Published: September 2023

The purpose of this research is to reduce the defect rate from manufacturing process of in-mould decoration (IMD), a process combining PET film with decorative patterns are moulded together with ABS resins, which has been developed to reduce the secondary process of decorative screen printing. Recently, the case study company has produced components with a high defect rate average 11.43% in Feb-Jun 2018, which increased sharply to 22.3% in June 2018. The major causes of the defect resulting from PET film peeled off and difficult to assembly. In order to reduce the defect rate, the five steps of the DMAIC Six Sigma methodology are implemented. The detail of the IMD manufacturing process was studied to identify appropriate measurement methods and factors affecting PET film peeled off by using the cause and effect diagram and its scoring matrix. Then the prioritized factors were analyzed and selected from FMEA to conduct the design of experiment (DOE) to find significant factors and optimal parameter settings for improvement and control process to prevent reoccurrence. After improvement of PET film peeled off by setting appropriate parameter as well as implementing control plans and Standard Operation Procedure (SOP) to eliminate other defects from in-mould decoration process, the result shows that the defect rate of in-mould decoration process decreased from11.43% average in Feb-June 2018 to1.25% after improvement in July-Oct 2018. It is found that IMD peeled off defect is reduce 86.6% and warpage defect is reduce 97.8% of defect before improvement.
Forecasting Hotel Daily Occupancy for High-Frequency and Complex Seasonality Data
Authors:   , Ungtrakul Phoom
Published: September 2023

Accurate hotel daily occupancy forecasting is an important input for hotel revenue management. This research presents forecasting models both time series and causal methods for a case study 4-star hotel in Phuket, Thailand. Holt-Winters, Box-Jenkins, Box-Cox transformation, ARMA errors, trend and multiple seasonal patterns (BATS), Trigonometric BATS (TBATS), back-propagation Neural Network (BPNN), and Support Vector Regression (SVR) are explored in this work, where Same Day Last Year is considered as benchmark forecast. For causal method, independent variables used as regressor inputs are transformed data observed in the past periods, the number of tourist arrivals from main countries to Phuket, Oil prices, exchange rate, etc. Accuracy for Aggregated data are tested using Mean Absolute Percentage Error (MAPE) and Mean Absolute Error (MAE). Findings suggested that back-propagation Neural Network (BPNN) outperforms other models with the lowest MAPE of 8.96%. However, SVR which gives second least error of 12.30% are not statistically different compared to BPNN, while all others are significantly different. It shows that Machine Learning techniques studied in this research outperform the sophisticated time series methods designed for complex seasonality data like BATS and TBATS. The results obtained can be applied to the case study hotel’s future planning about the forecasted number of left-over rooms so that they effectively allocate to their discounted online travel agent (OTA) more effectively.
Designing Modular Fixture for Automotive Condenser Inspection
Authors:   , Lertkajornkitti Tanest
Published: September 2023

In the automotive component manufacturing industry, the automotive parts must be produced with high precision according to the standard. And, to achieve such a goal, inspection fixtures are typically used as final inspection tools. These fixtures are highly specialized that often match only one stock-keeping unit of the condenser (SKU) each. Based on such a fact, as the number of SKUs rises, the number of fixtures produced would be inevitably increased, along with the resources required for fixture production, storage space, and maintenance. In order to address such issues, we explore and develop a new fixture design that turns specialized fixture into a more flexible one consuming less resources. This new fixture design is based on a modular fixture concept, where various fixture designs are proposed; but, the 3-level one is selected as it provides the best results compared to the rest and the original design. We find that this new design could potentially reduce the production cost by 240,000 Baht per year and save up to 29 cubic meters.
Thin Cloud Removal Using Local Minimization And Image Transformation In HSI Color Space
Authors:   , Markchom Thanet
Published: September 2023

In the use of satellite images, clouds can be an obstacle due to their opacity property that can block the visibility of ground objects in case of thick clouds and can also be blended with the underlying details in case of thin clouds. In this research, we propose a novel method to remove thin clouds and retrieve the actual information by taking the advantage of HSI color space instead of RGB color space. The proposed method aims to estimate the cloud appearance called the scattering light, remove thin clouds from intensity channel to avoid an effect to the original color, adjust the intensity with gamma correction to recover some information accidentally removed from the previous step, and restore obscure details by using contrast limited adaptive histogram equalization to enhance the intensity result. Furthermore, since thin clouds also affect saturation channel, we propose to increase saturation reduced as the result from thin clouds by using logarithm image transformation as well. From the results, the proposed method can remove clouds that are not extremely opaque and preserve the actual information such as color and texture according to the lowest mean squared error values between the outputs and their cloud-free images in the same position taken at the closest time, and the output images and their contrast gained values when compared to those obtained from other single-image methods.
Role of E-commerce on Trading Sector in China
Authors:   , Li Jinyi
Published: September 2023

E-commerce is rapidly developing along with the development of information technology in China. This paper is aimed at analyzing the contribution of E-commerce on the trading sector in China and estimating the macroeconomic and sectoral impact of E-commerce respectively by using fixed effect panel data based on the data from seven selected regions in China over the period of 2008-2016. The study found that E-commerce plays a significant and positive role in the economic growth at either macroeconomic level or sectoral level. Every 1 percent increase in E-commerce's sale leads to an increase of 0.54 percent in the output in the trading sector. E-commerce has a great influence on trade sector, and it has become one of the main driving forces for economic development in China.
The Relationship between FDI and Employment in China's Manufacturing Industry
Authors:   , Wang Ruoheng
Published: September 2023

China has achieved rapid economic growth after reforming and opening up, becoming the second largest economy after the United States. At the same time, China began to attract foreign direct investment, and the scale of foreign direct investment has been becoming larger and larger. It’s obvious that FDI has played a crucial role in promoting China's economic growth. But China is a country with a big population, the employment problem is the most direct and realistic problem. Although overall employment is increasing in China, the speed of employment growth in the manufacturing industry is very low. After all, the manufacturing industry is the main industry in China. So, there has been an expectation that foreign investors would bring not only new technology and capital, which would accelerate structural changes, but would also maintain employment. The topic of this paper is to analyze the relationship between FDI and employment in China’s manufacturing industry. In particular, this study explores the role differential effect of FDI in low-tech and high-tech manufacturing industries. This analysis was conducted using OLS regression models estimated for panel data between 1999 to 2015. And this paper also explores the real relationship between FDI and employment in the manufacturing industry of China through four company cases. The result shows that there is a significant positive relationship between FDI and employment for the entire manufacturing industry of China, and FDI has a greater effect on high-tech manufacturing industries than low-tech manufacturing industries. But in the company cases, the effect of FDI on employment in high-tech and low-tech manufacturing industry are not much different.
An empirical study of human capital on economic growth: An investigation using three indices of human capital
Authors:   , Fu Shan
Published: September 2023

This research reexamines the augmented Solow’s growth model to find the relationship between human capital and economic growth by using three different proxies for human capital. The first proxy of human capital is the proportion of labor force with secondary education that has been widely used in many studies. PISA score is the second proxy to human capital. It is regarded as being quality of education because this standardized test score could directly reflect the cognitive ability of individuals. The third proxy is the human capital index constructed by Penn’s World Table 9.0 that included both quantitative and qualitative aspects of human capital. The study also includes physical capital into the estimation of economic growth. The equilibrium growth model was firstly estimated based on the cross-section data of 21 middle-income countries and 36 high-income countries from 2010 to 2016. An alternative approach of estimation is the panel fixed effects model of 46 countries from 2010 to 2013 to allow different country-specific effects. Consistently with most studies, our result indicated that both physical capital and human capital are crucial factors to drive economic growth. The study found that human capital has played a positive role in economic growth in all proxies. However, it has been found that the most significant proxy is an index from Penn’s. An important implication of the findings is to confirm that human capital indicator should not only deal with a number of highly educated workers but it should also cover features in labor productivity improvement in an economy.
Influence of South Korea's Soft Power on The Extension of Korean Language in Thailand
Authors:   , Onnom Kunathai
Published: September 2023

The research named “Influence of South Korea’s Soft Power on the Extension of Korean Language in Thailand”, has aimed to understand and explain the background of South Korea’s soft power in a globalization context. The research will emphasize on the extension of Korean soft power to Thailand by using the Korean language as a key instrument. About the methodology, this research firstly collected the document information from reviewing previous researches, books, articles and other online sources. As being the qualitative research, the in-depth interview has proceeded discreetly with 25 key informants from many related-fields such as undergraduate students, employees, businessman and educational personnel. About the result, the literature review has fully provided the background and progression of soft power and globalization in South Korea. Furthermore, it has explained the way South Korea’s soft power has landed in Thailand. The in-depth interview has examined the correction from document information, indicated the competitive advantages of soft power’s resources and clearly presented the maintenance of Korean Wave trend in Thailand. Regarding the research findings, the rapid upsurge in Korean language learners in Thailand has resulted from the influence of South Korea’s soft power in various patterns including, an entertainment media; music, dramas, movies, TV programs and celebrities, the newfangled technology, food, goods, games and so on. These resources aroused the perceptive demand in Thai people, then lead to the demand for learning the Korean language and producing skilled workers to sustain a supply chain. Finally, those workers will return to support resources manufacturing and the extension of the market that are now maintaining the power of Korean Wave in Thailand.
The socio-cultural impacts of professional football clubs on local residents in the socialist republic of Vietnam
Authors:   , Huynh Tri
Published: September 2023

Objectives. The purpose of study is to explore the socio-cultural impacts of professional football clubs on local residents in the Socialist Republic of Vietnam; then, to find out the differences on the socio-cultural impacts of professional football clubs on local residents amongst the three regions such as Northern, Central and Southern Vietnam. Methods. Data were collected from 1,500 local residents were based on a convenience sample from six cities representative for three regions in Vietnam. After collecting the data, the entire data set was randomly split into two parts for exploratory factor analysis by IBM SPSS version 22.0 and confirmatory factor analysis by LISREL 9.30 in order to confirm the factor structure of the scale of socio-cultural impacts. Then, the research applied frequency, descriptive statistics and one-way ANOVA to satisfy the purposes of this study. Results. Results of the EFA and CFA identified the four impact factors including three positive impacts and one negative impact with a 37-item model provided a good fit to data. In the socio-cultural impact, Community Enhancement & Consolidation had the highest mean score and Socio-cultural & Environment Concerns had the lowest mean score. ANOVA tests determined that two factors exhibited significantly differences amongst the regions were Socio-cultural & Environment Concerns and Health & Socio-cultural Opportunities with p-value < .01. Conclusion. It is concluded that local residents have positive perceptions on socio-cultural impacts from professional football clubs in their communities. Last but not least, as comparing these socio-cultural impacts amongst three regions, the local residents in the Northern region responded their perceptions on both positive and negative were statistical significantly higher than residents in other regions in the Socialist Republic of Vietnam.
Critical exponent for nonlinear nonlocal equations
Authors:   , Manui Auttawich
Published: September 2023

In this thesis, we study the nonlinear nonlocal equation ∂t u=J*u-u+u¹+p where p>0 and J is nonnegative, bounded, and radially symmetric with unit integral. The Fourier transform of J satisfies J ̂(ξ)=1-A|ξ|^β (ln1/|ξ| 〗 )^μ+o(〖|ξ|〗^β (ln〖1/(|ξ|)〗 )^μ ) as ξ→0, for 0<β≤2, μ∈R, and A>0. In this study, we establish the local existence, uniqueness, and the comparison principle of solutions. Furthermore, we show that the Fujita critical exponent for this equation is β/n when μ<0. For the case μ>1, we discover that the critical exponent is β/n , and the solutions belong to the global to the small initial data regime.
Streaming data classification method using scalable hyper-ellipsoids with linear discriminant projection distance ratio
Authors:   , Rungcharassang Perasut
Published: September 2023

Learning streaming data with limited size of memory storage becomes an interesting problem. Although there have been several learning methods recently proposed, based on the interesting concept of discard-after-learn, the performance of these issues: the learning speed, number of redundant neurons, and classification accuracy of these methods can be further improved in terms of faster speed, less number of neurons, and higher accuracy. The following new four concepts and approaches were proposed in this dissertation: (1) a more generic structure of hyper-ellipsoidal function called Scalable Hyper-Ellipsoidal Function (SHEF) capable of handling the problem of curse of dimensionality by introducing a regularization parameter into the covariance matrix of SHEF; (2) a new recursive function to update the covariance matrix of SHEF based on only the incoming data chunk; (3) a fast and easy conditions to test the states of being overlapped, inside, or touch of two SHEFs; (4) a new distance measure for determining the class of a queried datum based on the projected distance on LDA discriminant vector. The experimental results show the significant improvement when compared with other methods.
Variant of D'alembert functional equation on compact homogeneous space
Authors:   , Viwanthananut Sorawit
Published: September 2023

In this work, we introduce a new functional equation on compact homogeneous spaces based on the d’Alembert functional equation on compact groups. We solve the functional equation by using tools from harmonic analysis.
The role of histone methylation of H3K4 in polarization of macrophages stimulated by immune complex and lipopolysaccharide and its therapeutic potential in sepsis
Authors:   , Ruenjaiman Vichaya
Published: September 2023

Macrophage plasticity is a process that allows macrophages to switch between two opposing phenotypes based on differential stimuli. Functional plasticity of macrophages contributes to disease pathogenesis such as cancer, metabolic diseases, autoimmune diseases and systemic infections. Epigenetics plays an important role in regulating this process. Macrophages stimulated with lipopolysaccharide (LPS) (M(LPS)) produce high level of pro-inflammatory cytokines such as IL-12, TNFα and IL-6 and low level of anti-inflammatory cytokine IL-10, while macrophages stimulated with LPS in the presence of immune complex (IC) (M(IC)) produce high level of IL-10 and low level of IL-12. In this study, we investigated the plasticity of M(LPS) to become M(IC) in vitro and compared the active histone mark (trimethylation on lysine 4 of histone 3 (H3K4me3)) between M(LPS) and M(IC) using murine bone marrow-derived macrophages. We found that macrophages exhibited functional plasticity from M(LPS) to M(IC) upon re-polarization after two days of resting in vitro. Phosphorylation of p38, p44/42, p65 and Akt in M(IC) re-polarized from M(LPS) was similar to M(IC) stimulated from resting macrophages. To obtain the epigenetic profiles of M(LPS) and M(IC), global H3K4me3 enrichments in both activated macrophages were compared. M(LPS) and M(IC) displayed marked differences in genome-wide enrichment of H3K4me3.  M(IC) showed increased global enrichment of H3K4me3 whereas M(LPS) decreased enrichment when compared to unstimulated macrophages. Furthermore, M(IC) exhibited high H3K4me3 enrichment in all cis-regulatory elements. At individual gene, increased H3K4me3 enrichments were observed in the promoters of known genes associated with M(IC) including Il10, Cxcl1, Csf3 and Il33 when compared with M(LPS). Finally, to evaluate the therapeutic application of M(IC), we investigated the impact of M(IC) on systemic immune response by adoptive transfer of M(IC) in LPS-induced endotoxemia model. Cytokine profiles revealed that mice receiving an adoptive transfer of M(IC) acutely reduced the serum inflammatory cytokines IL-1β and IL-p12p70. This study highlighted the importance of epigenetics in regulating macrophages activation and functions of M(IC) that may influence macrophage plasticity and the potential therapeutic use of macrophage in vivo.
HSV-1 induces filopodia formation in activated T lymphocytes
Authors:   , Sasivimolrattana Thanayod
Published: September 2023

Herpes simplex virus type 1 (HSV-1) is a widespread pathogen, which has diverse clinical manifestations from mild localized infection to severe systemic infection. The tissue tropism of HSV-1 is mainly epithelial and mucosal cells. However, it can also multiply in T lymphocytes suggesting a cause of viremia. In this study, CD3+CD4-CD8- Jurkat T lymphocytes were used. Under activation, up-regulation of CD69 molecules on cell surface was observed. Increase yield of HSV-1 production in activated T lymphocytes was demonstrated. In addition, most of HSV-1 virion progenies from infected T lymphocytes were released extracellularly, suggesting the cause of dissemination. The mechanism which supports HSV-1 infection in activated T lymphocytes is unclear. In epithelial cells, HSV-1 induce filopodia formation which constructed by actin polymerization to support their infectivity. Moreover, in those type of cell, filopodia formation are regulated by Cdc42, a member of Rho GTPase protein. In this study, the trend of β-actin mRNA expression was increased after HSV-1 infection in both activated and non-activated cell while the statistically different was found at protein level. β-actin expression was overexpressed after HSV-1 infection in activated T lymphocytes and decreased in cytochalasin D (cyto D), an inhibitor of actin polymerization and depolymerization of actin filaments formed, treated cells. This result indicated that actin plays role during HSV-1 entry in activated T cells. Moreover, Cdc42 was induced by HSV-1 whereas the expression of other Rho GTPase proteins was not changed. During viral entry, filopodia formation was observed in HSV-1-infected activated T lymphocytes suggesting filopodia formation might play role in HSV-1 entry in T-lymphocytes similar to epithelial cells. Observation under electron microscope suggested that HSV-1 entered into activated T lymphocytes via fusion and endocytosis pathway. In addition, HSV-1 titer in cyto D treated activated T lymphocytes was decreased indicating that actin polymerization plays role in HSV-1 infection of activated T lymphocytes. In conclusion, in activated T lymphocytes, filopodia formation, induced by HSV-1 infection was constructed by actin polymerization through Cdc42 which then resulted in increased yield of HSV-1 production.
Extraction of spent green tea leaves as bioactive-compound source
Authors:   , Yannarat Monsichar
Published: September 2023

Spent green tea leaves (SGTL) are a major contributor to the high cost of commercial tea products because of the large amount of leftover and the cost of disposal. This research investigates on the solvent and time for the extraction of SGTL that provides good yield of potential compound and to separate bioactive compounds as enrich-fractions and pure compounds. The obtained fractions were evaluated for antioxidant, antityrosinase, anticholinesterase and plant growth regulator activities. Caffeine was found in all samples. Among five extracts, the dichloromethane extract revealed high caffeine content (92.8 %peak area), while the methanol extract showed the highest five-catechin content (64.5 %peak area). Further separation of the latter by liquid-liquid extraction, the aqueous phase was extracted with ethyl acetate to gain high catechin family content (EGC, C, EC, EGCG, ECG) fraction with low caffeine. Four subfractions were separated from enrich-catechin family fraction. The enrich-caffeine and enrich-catechin family fractions displayed remarkable biological effects. Caffeine, gallic acid and ECG were bioactive compounds responsible for the biological activity in SGTL. Bioactive compound were isolated from SGTL showed bilogical activity including antioxidant, antityrosinase, anticholinesterase and plant growth regulation. SGTL was proved to be an excellent source of bioactive compounds. The enrich fractions served as prospective materials for the exploration of new multi-functional food and drug formulations.
Metabolic engineering of synechococcus elongatus pcc 7942 for mycosporine-2-glycine production under salt stress condition
Authors:   , Pingkhanont Panwad
Published: September 2023

ไมโครสปอรีน-ไลก์ อะมิโน แอซิด (MAAs) เป็นกลุ่มของสารเมแทบอไลต์ทุติยภูมิ สังเคราะห์โดยจุลินทรีย์และสาหร่ายหลายชนิด สารกลุ่มนี้มีหน้าที่สำคัญในการคัดกรองรังสียูวี และยังมีหน้าที่อื่นๆ ได้แก่ การต้านอนุมูลอิสระ ปกป้องเซลล์จากภาวะเครียด และควบคุมการออสโมซิส โดยไมโครสปอรีน-2-ไกลซีน (M2G) เป็นหนึ่งในสารกลุ่ม MAAs ที่มีความสามารถในการต้านอนุมูลอิสระมากกว่าสารอื่นๆ ในกลุ่มเดียวกัน ดังนั้นจึงเป็นที่สนใจที่จะเพิ่มการผลิต M2G เพื่อนำไปประยุกต์ใช้ในอุตสาหกรรมความงาม และเวชสำอาง ในการศึกษานี้ประสบความสำเร็จในการแสดงออกของยีนในชีวสังเคราะห์ M2G (Ap3858-3855) จาก Aphanothece halophytica ในไซยาโนแบคทีเรียน้ำจืด Synechococcus elongatus PCC 7942 จากการวิเคราะห์การถอดรหัสของยีน Ap3858-3855 พบว่า ยีนทั้ง 4 ยีนนี้เป็น monocistronic mRNA  heterologous expression ของยีน Ap3858-3855 ใน S. elongatus พบว่าทุกยีนมีการแสดงออกมากขึ้นภาวะเครียดจากเกลือ NaCl ยีน Ap3857 แสดงออกเพิ่มมากที่สุด 2.39 ± 0.25 เท่า และภายใต้ภาวะเครียดจากเกลือ KCl ยีน Ap3856 แสดงออกเพิ่มมากที่สุด 3.70 ± 0.35 เท่า ระดับการแสดงออกของยีนที่เกี่ยวข้องกับภาวะเครียดออกซิเดชั่น (sodB, cat และ tpxA) ในเซลล์แสดงออก พบว่าภายใต้ภาวะเครียดจากเกลือ NaCl มีเพียงยีน tpxA แสดงออกมากขึ้น 4.58 ± 0.58 เท่า ขณะที่ภาวะเครียดจากเกลือ KCl กระตุ้นการแสดงออกของ sodB และ tpxA 4.09 ± 0.86 และ 11.81 ± 1.02 เท่า ตามลำดับ ส่วนการแสดงออกของยีนที่เกี่ยวข้องกับสารออสโมไลท์ ได้แก่ Synpcc7942_0808 และ Synpcc7942_2522 พบว่าในเซลล์แสดงออกที่เจริญภายใต้ภาวะเครียดจากเกลือ NaCl มีเพียงยีน Synpcc7942_0808  มีการแสดงออกมากขึ้น 3.89 ± 0.30 เท่า และภายใต้ภาวะเครียดจากเกลือ KCl พบว่า Synpcc7942_0808 และ Synpcc7942_2522 แสดงออกมากขึ้น 9.40 ± 0.88 และ 3.52 ± 0.29  เท่า ตามลำดับ จากตรวจสอบการแสดงออกของโปรตีน โดยวิธีเวสเทิร์น บลอท พบแบนจำเพาะของโปรตีนเป้าหมาย คือ DDG-synthase (ถอดรหัสจากยีน Ap3858) โดยในเซลล์แสดงออกที่เจริญภายใต้ภาวะเครียดจากเกลือ NaCl มีการแปลรหัสได้โปรตีนมากขึ้นถึง 7.20 เท่า ส่วนการวิเคราะห์สารเมแทบอไลต์ พบว่ามีการสะสมของ M2G เพิ่มขึ้นภายใต้ภาวะเครียดจากเกลือทั้งสองชนิด โดยมีการสะสมของ M2G เพิ่มมากที่สุดภายใต้ภาวะเครียดจากเกลือ NaCl เมื่อเติมเซอรีน 7.35 ng/mgFW
Production of 1, 12- dodecanedioic acid by recombinant microbial cytochrome P450 in pichia pastoris and saccharomyces cerevisiae
Authors:   , Buathong Phawadee
Published: September 2023

1,12-Dodecanedioic acid (DDA) is a primary compound which is used as an intermediate precursor for production of valuable chemical products. Biosynthesis of 1,12-DDA by recombinant (r) microorganisms can be used as an alternative method to compensate several disadvantages from chemical synthesis. The purpose of this study was to clone a CYP52A17 from Candida tropicalis to produce cytochrome P450 which can terminally oxidize fatty acids to hydroxy-fatty acids and further to dicarboxylic acids (ω-oxidation). The wild type rCYP52A17 and its engineered L261S/L490S (leucine changed to encode for serine) form (rCYP52A17mut) were expressed in Pichia pastoris and Saccharomyces cerevisiae which coexpressing the yeast NADPH cytochrome P450 reductase in order to produce 12-hydroxydodecanoic acid (HDDA) and, potentially, 1,12-DDA from lauric acid. The P450 contents of microsomes from P. pastoris/pPICZA-CYP52A17 and P. pastoris/pPICZA-CYP52A17mut were 0.2 nmol/mg of protein. P. pastoris/pPICZA-CYP52A17 and CYP52A17mut presented a few the oxidation ability. The recombinant P. pastoris/pPICZA-CYP52A17mut accumulated the highest level of 12-HDDA (0.8 µM) within 24 h. The recombinant S. cerevisiae expressing rCYP52A17 showed higher P450 contents than the others. The P450 content of microsomes from S. cerevisiae BY(2R)/pYeDP60-CYP52A17 and S. cerevisiae BY(2R)/pYeDP60-CYP52A17mut were 0.13 and 0.28 nmol/mg of protein, where lauric acid was oxidized to provide approximately 4 and 12 µM of 12-HDDA, respectively. Moreover, biotransformation of lauric acid by S. cerevisiae BY(2R)/pYeDP60-CYP52A17mut showed the highest level of HDDA (45.8 µM) at 24 h, which was oxidized to yield 20.8 µM 1,12-DDA at 72 h. The optimal lauric concentration of biotransformation was 500 µM, while the levels of HDDA and 1,12-DDA production in bioreactor were almost similar to the shake flask cultivation. The recombinant yeast cells which initially cultured in YPGE can be able to produce the highest 1,12- DDA from coconut milk wastewater in 24 h. From this study, S. cerevisiae BY(2R)/pYeDP60-CYP52A17mut demonstrated as a promising source to produce potential 1,12-DDA and can be applied for industrial applications.
Perceptions, expectations, and satisfaction of patients undergoing dental implant therapy in the Faculty of Dentistry, Chulalongkorn University
Authors:   , Sermsiripoca Khunsiri
Published: September 2023

The aims of this study were to evaluate patient’s perception before and after receiving dental implant therapy and to investigate patient’s perception, expectation, and satisfaction of dental implant treated by postgraduate dental students and faculty members. This study was designed with a quantitative cross-sectional technique. The data were collected by 3 questionnaires, from patients who intended to receive dental implant treatment during September 2017 to February 2019. Two hundred and fifty participants participated in this study. Most of them were female, aged 55-64 years, graduated bachelor’s degree, and facial and teeth appearance did not affect their career. The proportion of monthly income was quite equally between groups. Most of participants were treated by faculty members and most likely to receive only 1 dental implant placement without bone augmentation. Most common site for implanting was posterior region. The perceptions after dental implant insertion were generally more accurate than prior treatment perceptions, except the higher level of agreement with statement “Dental implant therapy is appropriate for all patients.” after the treatment. In addition, the expertise of dentist significantly affected patient’s perceptions toward dental implant therapy. In conclusion, there were statistically significant differences between pre- and post-treatment perception of patients in almost all statements. Most participants improved their realistic perception after dental implant treatment. However, some patients still had improper perception and unrealistic expectation. Therefore, the appropriate information about dental implant including surgical procedure, post-operative difficulties, and preparation for maintenance program should be more intense provided to prevent the wrong conception, which might affect their satisfaction to the treatment outcome.