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2023

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Vegetation Dynamics And Sea-Level Changes In The Upper Gulf Of Thailand, Dissaya Sukaudom Jan 2023

Vegetation Dynamics And Sea-Level Changes In The Upper Gulf Of Thailand, Dissaya Sukaudom

Chulalongkorn University Theses and Dissertations (Chula ETD)

Climate change plays a role in sea level fluctuation, either transgression or regression leads to coastline evolution. Samut Sakhon province is located on the coast in the upper Gulf of Thailand therefore past sea-level studies in this area can contribute information to a better understanding of sediment dynamics and assess future coastline development. The study site provides sedimentary sequences consisting of 9 sediment units from 25.5-7.2 m. DBS, results of LOI, Ti/Ca, and Zr/Rb ratio, grain size, and pollen analysis were interpreted together with radiocarbon dating to reconstruct past environments in the study site. The past environment in Samut Sakhon …

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The Use Of Diatoms (Amphora Sp.) As Immunostimulant In Pacific White Shrimp (Litopenaeus Vannamei) Diet, Ekthida Thongdet Jan 2023

The Use Of Diatoms (Amphora Sp.) As Immunostimulant In Pacific White Shrimp (Litopenaeus Vannamei) Diet, Ekthida Thongdet

Chulalongkorn University Theses and Dissertations (Chula ETD)

Amphora sp. is one of the interesting microalgae due to its rapid growth, high lipid content, ranging from 40-60% of dry biomass, suitability as live food for commercial aquatic animal larvae such as shrimp and abalone. The objective of this study is to evaluate the potential of Amphora sp. isolated from four different locations in the Gulf of Thailand: Sichang Island (ASC), Samae Sarn Island (ASS), Pranburi (APB), and Laem Yai (ALY) as immunostimulant in Pacific white shrimp (Litopenaeus vannamei) diet. Four Amphora sp. isolations were cultured and compared productivity. The results showed that ASC and ALY had higher productivity, …

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Chitosan Blending With Water-Soluble Polymers As Dissolving Microneedles For Controlled Drug Release, Fuad Abdullah Farhan Saleh Jan 2023

Chitosan Blending With Water-Soluble Polymers As Dissolving Microneedles For Controlled Drug Release, Fuad Abdullah Farhan Saleh

Chulalongkorn University Theses and Dissertations (Chula ETD)

Chitosan has gained significant interest due to its ability to film-forming, biodegradability, and biocompatibility, making it suitable for topical and transdermal drug delivery such as fabricating microneedles. In this study, chitosan microneedles were prepared by incorporating polyvinylpyrrolidone (PVP) and polyvinyl alcohol (PVA) in three different ratios (1:1, 2:1, and 3:1 chitosan: polymers) to control drug release. The microneedles were fabricated using a molding method, their mechanical properties were tested using the universal testing machine (UTM), and their skin penetration ability was tested using pig skin (ex vivo). The results indicated that the microneedles exhibited sufficient strength to penetrate the outer …

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Health Risk And Ecological Risk Assessment From Microplastic Contamination In Sea Salt : Case Study In Ban Laem Salt Field, Phetchaburi, Thailand, Kusuman Promdontree Jan 2023

Health Risk And Ecological Risk Assessment From Microplastic Contamination In Sea Salt : Case Study In Ban Laem Salt Field, Phetchaburi, Thailand, Kusuman Promdontree

Chulalongkorn University Theses and Dissertations (Chula ETD)

Microplastics are ubiquitous in all terrestrial and aquatic environments. In this research, microplastic contamination in sea salt produced from traditional and plastic salt fields was studied. Including seawater used as a raw material for producing sea salt in Ban Leam salt fields, Phetchaburi, Thailand. Random samples were collected 3 replicates per point, for a total of 42 samples. 5M NaCl solution was used to separate the density and digest the organic substances using 0.05 M Fe (II) and 30% H2O2. The shape and color of the microplastics were characterized using a 30x magnification microscope. The amount, size, and polymer type …

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Evaluation Of Recreational Surface Water Quality According To Water Quality Index And Quantitative Microbial Risk Assessment Of Noroviruses And Sars-Cov-2, Parichart Soisoongnern Jan 2023

Evaluation Of Recreational Surface Water Quality According To Water Quality Index And Quantitative Microbial Risk Assessment Of Noroviruses And Sars-Cov-2, Parichart Soisoongnern

Chulalongkorn University Theses and Dissertations (Chula ETD)

Outbreak of waterborne virus are the major concern worldwide. The Water Quality Index (WQI) is a tool used to assess water quality for related activities. However, its suitability for assessing risks associated with waterborne pathogens remains questionable. This study aims to identify potential limitations and gaps in the WQI, especially in the context of risks from waterborne pathogens. The WQI of Maha Sawat Canal (MSC), Thailand was evaluated during both wet and dry seasons. The results were then integrated with the quantitative microbial risk assessment (QMRA) methodology for norovirus GI (NoV GI) and SARS-CoV-2. The results have shown that NoV …

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Forecasting Air Quality Index In Thailand Using Ensemble Method, Saksiri Lertnilkarn Jan 2023

Forecasting Air Quality Index In Thailand Using Ensemble Method, Saksiri Lertnilkarn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Air pollution is one of the most important problems that needs to be urgently solved around the world. Inevitably, Thailand has had to fight against it as well, particularly in the Northern Thailand. This region also has faced high air contamination for several years. In this thesis, the proposed model based on ensemble method was presented to predict the extent of air quality index (AQI) in the region from the majority vote of outputs from three classification algorithms, namely, support vector machine, random forest, and k-nearest neighbors. This proposed method made a comparison between the voted classification accuracy and the …

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Information Security Awareness Lesson Using Gamification, Thanawat Rintanalert Jan 2023

Information Security Awareness Lesson Using Gamification, Thanawat Rintanalert

Chulalongkorn University Theses and Dissertations (Chula ETD)

In the landscape of education, where engagement and retention are pivotal, gamification emerges as a dynamic strategy. This research delves into the realm of gamification, a process that infuses the captivating allure of videogame mechanics into educational contexts. Embarking on an experimental journey, this study orchestrates an intricate interplay between two distinct groups of undergraduate students – Group A, the "Gamified Group," and Group B, the "Traditional Group." Within this dynamic framework, Group A immerses itself in the immersive realm of educational videogames to grasp the nuances of information security awareness. In parallel, Group B embraces a more traditional approach, …

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Correlation Between Virus Reduction And Trihalomethanes Risk After Chlorine Disinfection, Waraporn Khantong Jan 2023

Correlation Between Virus Reduction And Trihalomethanes Risk After Chlorine Disinfection, Waraporn Khantong

Chulalongkorn University Theses and Dissertations (Chula ETD)

While wastewater disinfection is essential to mitigate the threats from waterborne pathogens, there arises a potential risk from disinfection byproducts. Striking a balance between achieving microbial reduction and managing the occurrence of disinfection byproducts is crucial for maintaining both microbial and chemical risks at acceptable levels. The cancer risk assessment was based on THMs through of oral ingestions, inhalation absorptions, and dermal absorptions exposure. This study aims to investigate the relationship between virus reduction and THMs formation, and to assess their respective cancer risk levels post-chlorination, and determined treatment process was used to decreased cancer risk post-chlorination. Effluent wastewater was …

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Prevalence And Genetic Characterization Of Porcine Circoviruses In Thai Swine Farms During 2019-2020, Chaitawat Sirisereewan Jan 2023

Prevalence And Genetic Characterization Of Porcine Circoviruses In Thai Swine Farms During 2019-2020, Chaitawat Sirisereewan

Chulalongkorn University Theses and Dissertations (Chula ETD)

To date, porcine circoviruses (PCVs), particularly PCV2 and PCV3, have been identified globally, while PCV4 is mainly found in Asia. This study aimed to investigate the prevalence and genetic characterization of PCVs in Thai swine farms during 2019-2020. Results showed PCV2 is the predominant species, followed by PCV3 and PCV4. For genetic analysis, the dominant novel PCV2d cluster with amino acid mutation (133HDAM136) in ORF2 was found in Thai swine farms that had not been detected in Thailand before. Moreover, inter-genotypic recombinant PCV2b/d was first identified in Thailand. The genetic analysis of PCV3 showed that PCV3 was grouped into PCV3a …

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Study Of Genetic Determinants To Explain Antimicrobial Resistance In Escherichia Coli And Salmonella Isolated From Food Animals, Meat And Humans In Thailand, Jiratchaya Puangseree Jan 2023

Study Of Genetic Determinants To Explain Antimicrobial Resistance In Escherichia Coli And Salmonella Isolated From Food Animals, Meat And Humans In Thailand, Jiratchaya Puangseree

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study comprised 4 parts. Different bacterial strains with different genotypes were used, depending on the experimental design and objectives. Part 1 - Plasmid profile analysis of E. coli and Salmonella enterica isolated from pigs, pork, and humans. This part aimed to characterize the profile of R plasmids in E. coli (n=1,047) and Salmonella (n=816). Sixteen and 11 Inc groups were identified in E. coli (85.3%) and Salmonella (25.7%), of which IncK-F (23.7%) and IncF (46.2%) were predominant. Plasmid replicon was significantly different among sources of isolates and sampling periods but significantly correlated with resistance phenotype (p<0.05). In conclusion, various plasmids are present in E. coli and Salmonella. The findings in this part form a basis for future studies to explore the possible methodology to counteract horizontal transfer of plasmids. Part 2 - Genomic analysis of Salmonella carrying class 1 integrons with dfrA12-aadA2 gene cassette array isolated from food animals, meat and human in Thailand. This part aimed to investigate the genetic characteristics of transferable plasmid carrying class 1 integrons with dfrA12aadA2 cassette array in 15 Salmonella isolates using Oxford Nanopore Sequencing technologies and Illumina platform. Seven MLST types and 6 clades of phylogenetic trees were identified. IncFIB(K), ColpVC, IncFIB, IncHI2, IncHI2A, IncX1, IncY and IncR plasmids were found. All had 28 AMR genes with the prediction to be resistant to various antibiotic groups. All isolates except B82 which was isolated from human, carried class 1 integrons with dfrA12-DUF1010-aadA2 and qacE-sul1 in conserved region. In conclusion, transferable R plasmids play an important role in the wide distribution of class 1 integrons with dfrA12-aadA2 gene array. Part 3 - Molecular basis of the persistence of chloramphenicol (CHP) resistance among E. coli and Salmonella spp. from food animals, meat and human in Thailand. This study aimed to explore the potential mechanisms associated with the persistence of CHP resistance in E. coli (n=106) and Salmonella (n=57). Most E. coli (67.9%) and Salmonella (64.9%) had ≥4-fold CHP MIC decrease in the presence of PAβN. Ampicillin, tetracycline, and streptomycin selective pressure yielded cmlA-carrying Salmonella and E. coli-transconjugants resistant to CHP (MIC 32-512 µg/mL). IncF plasmids were common in cmlA-carrying Salmonella and E. coli transconjugants. The WGS analysis revealed cmlA1-class1 integrons flanked by IS26 and TnAs1 in IncX1 plasmid, IncFIA(HI1)/HI1B plasmids and IncFII/FIB plasmids, and catA flanked by IS1B and TnAs3 in IncFIA(HI1)/HI1B/Q1. In conclusion, the persistence of CHP-resistance was potentially mediated by cross resistance via multidrug efflux systems using proton motif force (pmf) and co-selection of CHP-resistance genes by other antimicrobials. Part 4 - Resistance to widely-used disinfectants and heavy metals and cross resistance to antibiotics in E. coli isolated from pigs, pork and pig carcass. This study aimed to determine the possible cross resistance between disinfectants/heavy metals and antibiotics in E. coli from pigs (n=643), pork (n=111) and pig carcasses (n=110) in Thailand. Exposure to triclosan (TCS), benzalkonium chloride (BKC) and chlorhexidine (CHX) selected for spontaneousresistant mutants exhibited cross resistance to at least one antibiotic. The presence of PAβN restored MICs of CHP and trimethoprim in BKC- and TCS-spontaneous resistant mutants but PAβN, CCCP and reserpine could not restore ciprofloxacin MIC in ciprofloxacin-resistant mutants with no gyrA and parC mutation. In conclusion, the widely used disinfectants and heavy metals serve as non-antibiotic selective pressure for emergence and spread of AMR via cross-resistance involved in pmf-dependent and/or independent mechanisms. Susceptibilities to disinfectants/heavy metals should be routinely monitored. For the overall conclusion, the objectives of this project were successfully achieved. Further studies are suggested for better understanding of AMR and implementing the strategic actions to contain AMR.

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Mycobacterial Infection In Siamese Fighting Fish (Betta Splendens) : Pathogen Characteristics, Pathogenicity, Pathogenesis, And Control Strategies, Nguyen Dinh Hung Jan 2023

Mycobacterial Infection In Siamese Fighting Fish (Betta Splendens) : Pathogen Characteristics, Pathogenicity, Pathogenesis, And Control Strategies, Nguyen Dinh Hung

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study conducted a comprehensive investigation into mycobacteriosis in Siamese fighting fish (Betta splendens), a disease that poses major challenges to the sustainability of the sector. In the first phase, five different Mycobacterium species (i.e., M. chelonae, M. cosmeticum, M. farcinogenes, M. mucogenicum, and M. senegalense) were meticulously characterized. Bacterial speciation was determined through phenotypic and biochemical characteristics. Concurrently, antibiotic resistance of the bacteria with MAR indices ranging from 0.22 to 0.61, indicated potential challenges in treatment strategies. Furthermore, disinfectant susceptibility revealed that ethanol, formalin, chlorine, and povidone-iodine were effective in killing the bacteria, while potassium permanganate was less effective. …

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Prevalence And Risk Factor Analysis Of Feline Blood-Borne Pathogens In Thailand, Nonsee Rodmanee Jan 2023

Prevalence And Risk Factor Analysis Of Feline Blood-Borne Pathogens In Thailand, Nonsee Rodmanee

Chulalongkorn University Theses and Dissertations (Chula ETD)

Feline blood-borne pathogens are infectious agents which knowledge of prevalence and risk factors for infection is important to recognize pathogens that should be screened in blood. A total of 298 samples (GROUP A) and 112 archived samples (GROUP B) were collected from client-owned cats attending the veterinary hospital of Chulalongkorn University, and private veterinary hospitals in Bangkok and vicinity. A total of 55 and 12 samples were positive for hemoplasmas in GROUP A and B, respectively. The species were ‘Candidatus Mycoplasma haemominutum’ and Mycoplasma haemofelis. DNA of Bartonella were detected in 10 and 12 samples from GROUP A and B, …

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Effect Of Cannabis Sativa Byproduct Supplementation During Transition Period On Maternal Behavior, Feed Intake, Colostrum Yield And Piglet Survival Rate In Hyperprolific Sows, Rafa Boonprakob Jan 2023

Effect Of Cannabis Sativa Byproduct Supplementation During Transition Period On Maternal Behavior, Feed Intake, Colostrum Yield And Piglet Survival Rate In Hyperprolific Sows, Rafa Boonprakob

Chulalongkorn University Theses and Dissertations (Chula ETD)

In the modern swine industry, addressing inflammation and pain in sows after farrowing is a crucial animal welfare concern. Cannabis sativa, a medicinal plant, possesses properties that serve as an analgesic, anti-inflammatory, and antipyretic, while also being abundant in fiber. The objective of this study is to examine the impact of supplementing sows with Cannabis sativa byproducts during transition periods on various aspects including postpartum behavior, feed intake, constipation, farrowing duration, colostrum yield, and piglet performance. The experiment involved a total of 100 Landrace × Yorkshire sows. The sows were distributed according to parity numbers into 2 groups, i.e., control …

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Surveillance And Genetic Characterization Of Severe Acute Respiratory Coronavirus Type 2 (Sars-Cov-2) Infections In Domestic Animals And Wildlife In Thailand, Waleemas Jairak Jan 2023

Surveillance And Genetic Characterization Of Severe Acute Respiratory Coronavirus Type 2 (Sars-Cov-2) Infections In Domestic Animals And Wildlife In Thailand, Waleemas Jairak

Chulalongkorn University Theses and Dissertations (Chula ETD)

SARS-CoV-2 caused a pandemic outbreak since December 2019 with global implications for public health, economy, and society. This dissertation entitled “Surveillance and genetic characterization of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) infections in domestic animals and wildlife in Thailand” investigates the transmission incidence and characterization of the virus between humans and animals. This thesis comprises 4 studies of the surveillance of SARS-CoV-2 in animals and wildlife species in Thailand from 2017 to 2023. The first investigation (Chapter 2) involved a survey of SARS-CoV-2 in domestic dogs and cats in Samut Sakhon province during the second wave of the …

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Food Tourism As A Means Of Promoting Food Sustainability: A Case Study Of Street Food In Bangkok, Marissa Soltoff Jan 2023

Food Tourism As A Means Of Promoting Food Sustainability: A Case Study Of Street Food In Bangkok, Marissa Soltoff

Chulalongkorn University Theses and Dissertations (Chula ETD)

In 2002, the Thai government lauched two gastrodiplomacy initiatives to promote cultural awareness, increase export revenue, and boost tourism by increasing the number and quality of Thai restaurants abroad. These iniatives have been vastly successful and have since been emulated by other countries. This paper builds on the gastrodiplomacy initiatives' success by exploring the possibility of the same methods being applied to promotion of food sustainability. This research addresses the questions surrounding the factors that both enable and risk food sustainability, the sustainability projects currently being pursued in Thailand, any possible link between food sustainability and gastrodiplomacy with regards to …

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Bad Genius: An Analysis Of Filmic Representations Of Thailand’S Social Issues And Chinese Viewers’ Perspectives, Shuwen Sun Jan 2023

Bad Genius: An Analysis Of Filmic Representations Of Thailand’S Social Issues And Chinese Viewers’ Perspectives, Shuwen Sun

Chulalongkorn University Theses and Dissertations (Chula ETD)

Bad Genius is a thought-provoking Thai movie that profoundly reflects the modern side of society by telling the story of examination malpractice and social class issues. The purpose of this article is to analyze the social issues involved in the film and explore the criticism of the education system and social injustice. At the same time, the article will introduce the Chinese audience's evaluation of the movie in order to analyze the reasons for its high box office in the Chinese market. By comparing the educational background and social values of Thailand and China, we can better understand why Bad …

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Analysis Of K-Food Franchises In Thai Market Focusing On The Consumption Behavior Of Thai Generation Y And Generation Z In Bangkok Metropolitan Region, Vajirawit Siripiyaphat Jan 2023

Analysis Of K-Food Franchises In Thai Market Focusing On The Consumption Behavior Of Thai Generation Y And Generation Z In Bangkok Metropolitan Region, Vajirawit Siripiyaphat

Chulalongkorn University Theses and Dissertations (Chula ETD)

These days, fans everywhere are enamored with the Korean Wave (Hallyu). South Korean administrations have highlighted Korean cuisine (K-food) as one of their exported cultural products. Localizing K-food abroad might cause misunderstandings among foreigners. Accordingly, franchising has the potential to maintain food authenticity. Thus, the purpose of this thesis was to examine the consumption behavior of Thai Generation Y and Z in relation to Korean franchise businesses in the Bangkok Metropolitan Region (BMR). The first analysis used the theory of planned behavior (TPB) together with a new variable regarding the food consumption behaviors of Koreans and Thais. Then, the examination …

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The Popularity Of Thai Y Series In Japan, Taiki Yamamoto Jan 2023

The Popularity Of Thai Y Series In Japan, Taiki Yamamoto

Chulalongkorn University Theses and Dissertations (Chula ETD)

The burgeoning popularity of the Thai Y series within Japan presents a captivating case study of cultural diffusion and media influence in the contemporary era. This paper explores the underlying dynamics behind this phenomenon, focusing on the interplay between social media's role in content propagation, the narrative appeal of the series to Japanese audiences, and the unique charm of Thai actors that captivates the same demographic. The research employs a multifaceted approach which incorporates examination of key media platforms, storytelling analysis, interview, and analysis of actors’ appeal. The findings reveal insights into the cultural, and social impact of the Thai …

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Assessing The Impacts Of Household Contacts In Covid-19 Transmission Dynamic Modeling Through Small-World Network, Thanagun Dheravijaranayankul Jan 2023

Assessing The Impacts Of Household Contacts In Covid-19 Transmission Dynamic Modeling Through Small-World Network, Thanagun Dheravijaranayankul

Chulalongkorn University Theses and Dissertations (Chula ETD)

In the context of the ongoing COVID-19 pandemic, understanding household transmission has become crucial for formulating effective intervention strategies. This research investigated the impact of considering heterogeneous contact patterns in household settings by leveraging the small-world network (SWN) concept, characterized by high local clustering and short average path length. The methodology involved developing an agent-based simulation model with a two-layer contact network, distinguishing between household and non-household contacts. This simulation aimed to explore the impact of contact patterns on transmission dynamics as well as provide insights into tailored intervention strategies. We evaluate seven Non-Pharmaceutical Intervention (NPI) scenarios focusing on reducing …

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Classification Of Android Malware From Binary Code Using Ensemble Method With Recursive Feature Elimination, Nawa Tippayasem Jan 2023

Classification Of Android Malware From Binary Code Using Ensemble Method With Recursive Feature Elimination, Nawa Tippayasem

Chulalongkorn University Theses and Dissertations (Chula ETD)

In response to the burgeoning Android market and the concurrent proliferation of both applications and malware, we propose a direct analysis approach to classify Android malware by examining bytecode extracted from DEX files. The prevalent use of obfuscation techniques by malicious actors underscores the need for robust methods to detect and analyze malware. Leveraging the frequency of bi-gram and tri-gram patterns within the bytecode, we employ recursive feature elimination with TF-IDF, alongside XGB, RF, and voting classifiers, to enhance detection capabilities. Our study, conducted using the CICAndMal2017 dataset, highlights the effectiveness of this approach, with XGB classifier utilizing the top …

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Development Of Environmentally Friendly Dental Waste Transportation Method In Myanmar, Phyo Thiri Kyaw Jan 2023

Development Of Environmentally Friendly Dental Waste Transportation Method In Myanmar, Phyo Thiri Kyaw

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study delves into dental waste management practices in Yangon City, Myanmar, with a primary focus on optimizing waste transportation routes for environmental sustainability. Through a comprehensive survey of 13 dental clinics in each of the 13 townships in the Western Yangon District, the research employs a blend of quantitative and qualitative methods, including survey, GIS analysis and observational studies. The optimization cases explore diverse strategies for waste transportation routes, revealing that Cases 2 and 3 surpass the baseline scenario in terms of travel distance. These tailored optimization strategies showcase the effectiveness of creating environmentally friendly waste collection routes for …

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Ph Modulation Of Arsenic Phytoextraction And Nutrient Uptake In Water Hyacinth (Eichhornia Crassipes (Mart.)), Hein Htet Aung Jan 2023

Ph Modulation Of Arsenic Phytoextraction And Nutrient Uptake In Water Hyacinth (Eichhornia Crassipes (Mart.)), Hein Htet Aung

Chulalongkorn University Theses and Dissertations (Chula ETD)

Arsenic contamination in water area poses significant threats to ecosystems as well as human health around the world. For reducing the rate of arsenic pollution, phytoremediation, which applies plant-based systems, could provide a long-term solution. A hyper-accumulating plant, water hyacinth (Eichhornia crassipes), which is known for its rapid growth and efficient nutrient uptake, has emerged as an attractive candidate for arsenic phytoextraction. However, the efficiency of arsenic removal by water hyacinth could be affected by a variety of environmental factors, including various ranges of pH in aquatic environments. This study investigates the effect of pH modulation on arsenic phytoextraction efficiency …

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Integrated Data Analysis, Neural Network Modeling, And Model-Based Control System For Biomass Gasification Processes, Kritsana Suwanamad Jan 2023

Integrated Data Analysis, Neural Network Modeling, And Model-Based Control System For Biomass Gasification Processes, Kritsana Suwanamad

Chulalongkorn University Theses and Dissertations (Chula ETD)

In the face of a global crisis including the problem of global warming and air pollution (PM 2.5). Renewable energy sources are gaining much attention, especially the biomass gasification process because in agricultural countries there is a lot of biomass waste incorrect management of waste biomass results in increased environmental problems. In addition, the gasification process from biomass has a low cost, the operation is simple and it can also synthesize syngas which can be used for many applications such as being a precursor to producing chemicals, fuels, electricity, and many more. Therefore, this research focuses on developing the gasification …

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โครงเนื้อเยื่อกินได้ไร้ผลิตภัณฑ์จากสัตว์สำหรับเพาะเลี้ยงเนื้อเทียม : อัลจิเนต/อะกาโรส/คาร์บอกซีเมทิลเซลลูโลส, เกรียงไกร เจษฎางกูร Jan 2023

โครงเนื้อเยื่อกินได้ไร้ผลิตภัณฑ์จากสัตว์สำหรับเพาะเลี้ยงเนื้อเทียม : อัลจิเนต/อะกาโรส/คาร์บอกซีเมทิลเซลลูโลส, เกรียงไกร เจษฎางกูร

Chulalongkorn University Theses and Dissertations (Chula ETD)

การเพาะเลี้ยงเนื้อสัตว์เป็นแนวทางในการลดทรัพยากรที่ใช้ในการผลิตเนื้อสัตว์แบบดั้งเดิม ซึ่งไม่ต้องฆ่าสัตว์และลดผลิตภัณฑ์ที่ไม่ต้องการ วิธีกระบวนการนี้ต้องการโครงเนื้อเยื่อ 3 มิติ เพื่อให้เซลล์สามารถยึดติดบนโครงสร้างและขึ้นรูปเป็นก้อนเนื้อได้ นอกจากนั้น วัสดุของโครงเนื้อเยื่อต้องไม่ทำจากสัตว์อีกด้วย วัตถุประสงค์ของการศึกษานี้เพื่อตรวจสอบสมบัติเชิงกล รีโอโลยี ความเข้ากันได้ทางชีวภาพ และการปรับปรุงพื้นผิวสำหรับการยึดเกาะของเซลล์ของไฮโดรเจล 2% w/v อัลจิเนต, 0.8% w/v อะกาโรส และ 1.5% w/v คาร์บอกซีเมทิลเซลลูโลส โครงสร้าง 3 มิติถูกพิมพ์ด้วยเงื่อนไขการพิมพ์ที่เหมาะสม การทดสอบทางรีโอโลยีและความสามารถการพิมพ์แสดงถึงไฮโดรเจลมีพฤติกรรมของของไหลที่ไม่ใช่แบบนิวโทเนียน ซึ่งเหมาะสำหรับวิธีการพิมพ์แบบอัดรีดสำหรับขึ้นรูปสามมิติ ผลการทดลองแสดงว่าไฮโดรเจลมีค่าความสามารถการพิมพ์สูงสำหรับระยะห่างระหว่างเส้นภายในโครงสร้างที่แตกต่างกัน การทดสอบรับแรงกดของชิ้นงานแสดงถึงเนื้อสัมผัสของไฮโดรเจลว่ามีความคล้ายคลึงกับความนุ่มของเนื้อหมูและเนื้อวัว ไฮโดรเจลมีอัตราการละลายต่ำในสภาวะการเพาะเลี้ยงเซลล์ การทดสอบความเป็นพิษต่อเซลล์บ่งชี้ว่าไฮโดรเจลไม่แสดงความเป็นพิษต่อเซลล์และไม่ส่งผลต่อการเพิ่มจำนวนเซลล์ ไฮโดรเจลต้องการการปรับเปลี่ยนพื้นผิวสำหรับการยึดเกาะของเซลล์เนื่องจากวัสดุไม่สนับสนุนการเจริญเติบโตและการยึดเกาะของเซลล์ ผลการทดลองแสดงว่าอัลจิเนตปรับปรุงเปปไทด์ RGD มีการยึดเกาะของเซลล์ต่ำกับทั้ง L929 และเซลล์ต้นกำเนิดกล้ามเนื้อหมู ในส่วนของการเคลือบสารละลาย Poly-L-ornithine แสดงผลลัพธ์การยึดเกาะของเซลล์ที่ดีกับ L929 แต่มีผลที่ไม่ดีสำหรับเซลล์ต้นกำเนิดกล้ามเนื้อหมู

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Modified Indion 225 H Ion-Exchange Resin For Acetylation From Glycerol With Acetic Acid, Pakin Sopolapikul Jan 2023

Modified Indion 225 H Ion-Exchange Resin For Acetylation From Glycerol With Acetic Acid, Pakin Sopolapikul

Chulalongkorn University Theses and Dissertations (Chula ETD)

Acetin is a high-value product derived from the esterification of glycerol and acetic acid. The global demand of acetin is increasing as it is a useful chemical for various industries. However, current catalysts are quite expensive and require complicated production steps. Therefore, exploring alternative catalysts for more efficient and cheaper production is essential. One such alternative catalyst is Indion 225 H resin, which is suitable for acetin production. This research studies the efficiency of this catalyst at different temperatures and various catalyst amounts (1-7%) in both a batch system and an azeotropic distillation system to enhance reaction efficiency. Additionally, it …

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Design And Fabrication Of An Anthropomorphic Robotic Finger With Dual Tendon Drives And Passive Stretch-Driven Elastic Members, Worathris Chungsangsatiporn Jan 2023

Design And Fabrication Of An Anthropomorphic Robotic Finger With Dual Tendon Drives And Passive Stretch-Driven Elastic Members, Worathris Chungsangsatiporn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Human hands are unparalleled in their dexterity, precision, and versatility, making them ideal models for robotic systems. Conventional robotic hands with standard joints cannot fully replicate human hand biomechanics, often resulting in increased weight, cost, and complexity. The primary objective is to develop a robotic finger that closely mimics anthropomorphic characteristics using computer-aided design (CAD) and rapid prototyping technology and to analyze its force and motion behaviors. The underactuated hybrid design combined soft and rigid elements and emphasizes passive adaptability to achieve dexterity. Rolling contact joints were applied to replicate varied rotational axis biomechanics. Springs and tendon routes were integrated …

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Effects Of Preparation Method For Titania On Silica Support On Catalyst Stability For Methyl Oleate Epoxidation, Warinya Sukkaew Jan 2023

Effects Of Preparation Method For Titania On Silica Support On Catalyst Stability For Methyl Oleate Epoxidation, Warinya Sukkaew

Chulalongkorn University Theses and Dissertations (Chula ETD)

Biomass is an outstanding raw material instead of fossil fuel because of its renewable and eco-friendly nature. In Southeast Asia in particular, there is an oversupply of palm oil. Converting palm oil into high-value products presents a promising solution. The major composition derived from palm oil is methyl oleate. Methyl oleate can be converted to epoxide product that is used in a broad application in the chemical industry through epoxidation. Ti-based catalyst is a promising candidate catalysts for epoxidation reactions. This work focuses on the epoxidation reaction of methyl oleate with hydrogen peroxide. For Ti-based catalysts, support is essential. The …

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Effect Of Brønsted And Lewis Acid On Ni-Based Bifunction Catalyst On Hydroprocessing Of Palm Oil To Biojet Fuel, Settapong Kantangkul Jan 2023

Effect Of Brønsted And Lewis Acid On Ni-Based Bifunction Catalyst On Hydroprocessing Of Palm Oil To Biojet Fuel, Settapong Kantangkul

Chulalongkorn University Theses and Dissertations (Chula ETD)

Jet fuels are mainly generated by refining petroleum feedstock, resulting in the emission of greenhouse gases. Therefore, biojet fuel is proposed as an alternative solution for solving this issue. Hydroprocessing of vegetable oils is an efficient pathway for producing biojet fuel. This process includes three reaction which are hydrodeoxygenation, hydrocracking and hydroisomerization over metal-acid catalyst. Biojet fuel series ranging from C8 to C16 must have a freezing point around -47 °C or lower, requiring the use of iso-paraffins which have low freezing points. There are challenges in improving the quantity and quality of biojet fuel production. This study aims to …

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Effect Of Co-Existing Parameters On The Adsorption Of Perfluorooctanoic Acid (Pfoa) On Powdered Activated Charcoal, Aung Thit Htun Jan 2023

Effect Of Co-Existing Parameters On The Adsorption Of Perfluorooctanoic Acid (Pfoa) On Powdered Activated Charcoal, Aung Thit Htun

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this study the adsorption of PFOA on three different commercial Powdered Activated Charcoal (PACs), wood-based, bamboo-based and coconut-shell-based activated charcoals, was explored. The influence of PACs characteristics on adsorption has been evaluated and the presence of oxygen containing functional groups significantly affect the adsorption mechanism. The adsorption equilibrium of PFOA, the initial concentration of 1 mg/L was achieved in 2 hours by the doses of 1.2 g/L of PACs. The effect of pH, adsorbent types, hardness ions and temperature in adsorption efficiency of PAC was investigated by batch experiments. The results of adsorption kinetic showed that PFOA adsorption on …

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Characterizing Particle Number Size Distributions And Source Contribution For Public Elementary School Classrooms In Bangkok, Hnin Phyu Phyu Aung Jan 2023

Characterizing Particle Number Size Distributions And Source Contribution For Public Elementary School Classrooms In Bangkok, Hnin Phyu Phyu Aung

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study characterizes particle number size distributions (PNSD) and source contributions for public elementary school classrooms in Bangkok. Using Scanning Mobility Particle Sizers (SMPS) and Optical Particle Sizers (OPS), measurements covered particle sizes from 10 nm to 10 µm during regular school hours on weekdays and under various experimental conditions on weekends. The particle number concentrations (PNC) showed significant fluctuations for all four schools with peak levels observed during morning rush hours coinciding with students' arrival and indoor activities. The findings revealed predominant Aitken mode particles both indoors and outdoors. During weekdays, the PNSD was significantly unimodal, with sigma (σ) …

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