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For People And Planet: Teachers’ Evaluation Of An Educational Mobile Game And Resource Pack, Ma. Mercedes T. Rodrigo, Johanna Marion R. Torres, Janina Carla M. Castro, Abigail Marie T. Favis, Ingrid Yvonne Herras, Francesco U. Amante, Hakeem Jimenez, Juan Carlo F. Mallari, Kevin Arnel C. Mora, Walfrido David A. Diy, Jaclyn Ting Ting M. Lim, Ma. Assunta C. Cuyegkeng Jan 2021

For People And Planet: Teachers’ Evaluation Of An Educational Mobile Game And Resource Pack, Ma. Mercedes T. Rodrigo, Johanna Marion R. Torres, Janina Carla M. Castro, Abigail Marie T. Favis, Ingrid Yvonne Herras, Francesco U. Amante, Hakeem Jimenez, Juan Carlo F. Mallari, Kevin Arnel C. Mora, Walfrido David A. Diy, Jaclyn Ting Ting M. Lim, Ma. Assunta C. Cuyegkeng

Department of Information Systems & Computer Science Faculty Publications

For People and Planet: An SDG Adventure refers to a freely available Android-based narrative adventure game and teacher resource pack that helps learners see the United Nations Sustainable Development Goals (SDGs) in their day-to-day lives. In this paper, we describe the results of an evaluation of both the game and the resource pack by eight (8) middle school teachers. After playing the game and reading the resource pack, teachers gave their feedback about what they liked best and least about the materials, how they could use these resources for their classes, and how these resources could be improved further. Overall, …


Factors Influencing Survival Rates Of Pronghorn Fawns In Idaho, Brett R. Panting, Eric M. Gese, Mary M. Conner, Scott Bergen Jan 2021

Factors Influencing Survival Rates Of Pronghorn Fawns In Idaho, Brett R. Panting, Eric M. Gese, Mary M. Conner, Scott Bergen

United States Department of Agriculture Wildlife Services: Staff Publications

Pronghorn (Antilocapra americana) occur throughout western North America. In Idaho, USA, following intensive hunting to reduce crop depredations in the late 1980s, pronghorn populations have not rebounded to desired levels. Because neonatal survival in ungulates is one factor limiting population growth, we evaluated cause‐specific mortality and the influence of intrinsic and extrinsic factors on survival rates of 217 radio‐collared pronghorn fawns across 3 study areas in Idaho during 2015–2016. For intrinsic variables, we determined the sex and body mass index (BMI) for each fawn. For extrinsic variables, we determined the abundance of predators and alternate prey, estimated the …


Powassan Virus Experimental Infections In Three Wild Mammal Species, Nicole M. Nemeth, J. Jeffrey Root, Airn E. Hartwig, Richard A. Bowen, Angela M. Bosco-Lauth Jan 2021

Powassan Virus Experimental Infections In Three Wild Mammal Species, Nicole M. Nemeth, J. Jeffrey Root, Airn E. Hartwig, Richard A. Bowen, Angela M. Bosco-Lauth

United States Department of Agriculture Wildlife Services: Staff Publications

Powassan virus (POWV) is a tick-borne virus maintained in sylvatic cycles between mammalian wildlife hosts and ticks (primarily Ixodes spp.). There are two currently recognized lineages, POWV-lineage 1 (POWV-L1) and deer tick virus (DTV; lineage 2), both of which can cause fatal neurologic disease in humans. Increased numbers of human case reports in the northeastern and north central United States in recent years have fueled questions into POWV epidemiology. We inoculated three candidate wildlife POWV reservoir hosts, groundhogs (Marmota monax), striped skunks (Mephitis mephitis), and fox squirrels (Sciurus niger), with either POWV-L1 or DTV. …


Measuring Adrenal And Reproductive Hormones In Hair From Southern Beaufort Sea Polar Bears (Ursus Maritimus), Marilize Van Der Walt, Lorin A. Neuman-Lee, Patricia A. Terletzky, Todd C. Atwood, Eric M. Gese, Susannah S. French Jan 2021

Measuring Adrenal And Reproductive Hormones In Hair From Southern Beaufort Sea Polar Bears (Ursus Maritimus), Marilize Van Der Walt, Lorin A. Neuman-Lee, Patricia A. Terletzky, Todd C. Atwood, Eric M. Gese, Susannah S. French

United States Department of Agriculture Wildlife Services: Staff Publications

Polar bears (Ursus maritimus) use sea ice to access marine mammal prey. In Alaska’s Southern Beaufort Sea, the declining availability of sea ice habitat in summer and fall has reduced opportunities for polar bears to routinely hunt on the ice for seals, their primary prey. This reduced access to prey may result in physiological stress with subsequent potential consequences to reproductive function (physiological changes that accompany reproduction), which can be measured via reproductive hormones. Hormone concentrations in hair can be used as a minimally invasive alternative to serum concentrations, which must come from animal captures. Hair samples also …


Dietary Flexibility Of Wood Storks In Response To Human-Induced Rapid Environmental Change, Betsy A. Evans, Jessica A. Klassen, Dale E. Gawlik Jan 2021

Dietary Flexibility Of Wood Storks In Response To Human-Induced Rapid Environmental Change, Betsy A. Evans, Jessica A. Klassen, Dale E. Gawlik

United States Department of Agriculture Wildlife Services: Staff Publications

Human-induced rapid environmental change (HIREC) has altered landscape processes and negatively impacted many species globally. Some of the most dramatic changes have been in wetlands where flows have been disrupted, and new wetlands have been created to retain runoff. In response to disrupted natural wetland conditions, Wood Stork (Mycteria americana) populations in South Florida have significantly declined over the past several decades. Despite the well-documented sensitivity of Wood Storks to natural wetland conditions, Wood Storks are often observed foraging in roadside created wetlands; however, the availability of prey in created wetlands is currently unknown. We sampled natural and created wetlands …


Transmission Routes Of The Microbiome And Resistome From Manure To Soil And Lettuce, Yuepeng Sun, Daniel D. Snow, Harkamal Walia, Xu Li Jan 2021

Transmission Routes Of The Microbiome And Resistome From Manure To Soil And Lettuce, Yuepeng Sun, Daniel D. Snow, Harkamal Walia, Xu Li

Daugherty Water for Food Global Institute: Faculty Publications

The land application of animal manure can introduce manure microbiome and resistome to croplands where food crops are grown. The objective of this study was to characterize the microbiome and resistome on and in the leaves of lettuce grown in manured soil and identify the main transmission routes of microbes and antibiotic resistance genes (ARGs) from soil to the episphere and endosphere of lettuce. Shotgun metagenomic results show that manure application significantly altered the composition of the microbiome and resistome of surface soil. SourceTracker analyses indicate that manure and original soil were the main source of the microbiome and resistome …


Nutritional Approach For Increasing Public Health During Pandemic Of Covid-19: A Comprehensive Review Of Antiviral Nutrients And Nutraceuticals, Vahideh Ebrahimzadeh-Attari, Ghodratollah Panahi, James R. Hébert Scd, Alireza Ostadrahimi, Maryam Saghafi-Asl, Neda Lotfi-Yaghin, Behzad Baradaran Jan 2021

Nutritional Approach For Increasing Public Health During Pandemic Of Covid-19: A Comprehensive Review Of Antiviral Nutrients And Nutraceuticals, Vahideh Ebrahimzadeh-Attari, Ghodratollah Panahi, James R. Hébert Scd, Alireza Ostadrahimi, Maryam Saghafi-Asl, Neda Lotfi-Yaghin, Behzad Baradaran

Faculty Publications

Background: The novel coronavirus (COVID-19) is considered as the most life-threatening pandemic disease during the last decade. The individual nutritional status, though usually ignored in the management of COVID-19, plays a critical role in the immune function and pathogenesis of infection. Accordingly, the present review article aimed to report the effects of nutrients and nutraceuticals on respiratory viral infections including COVID-19, with a focus on their mechanisms of action.

Methods: Studies were identified via systematic searches of the databases including PubMed/ MEDLINE, ScienceDirect, Scopus, and Google Scholar from 2000 until April 2020, using keywords. All relevant clinical and experimental studies …


Female Pacific Walruses (Odobenus Rosmarus Divergens) Show Greater Partitioning Of Sea Ice Organic Carbon Than Males: Evidence From Ice Algae Trophic Markers, Chelsea W. Koch, Lee W. Cooper, Ryan J. Woodland, Jacqueline M. Grebmeier, Karen E. Frey, Raphaela Stimmelmayr, Cédric Magen, Thomas A. Brown Jan 2021

Female Pacific Walruses (Odobenus Rosmarus Divergens) Show Greater Partitioning Of Sea Ice Organic Carbon Than Males: Evidence From Ice Algae Trophic Markers, Chelsea W. Koch, Lee W. Cooper, Ryan J. Woodland, Jacqueline M. Grebmeier, Karen E. Frey, Raphaela Stimmelmayr, Cédric Magen, Thomas A. Brown

Geography

The expected reduction of ice algae with declining sea ice may prove to be detrimental to the Pacific Arctic ecosystem. Benthic organisms that rely on sea ice organic carbon (iPOC) sustain benthic predators such as the Pacific walrus (Odobenus rosmarus divergens). The ability to track the trophic transfer of iPOC is critical to understanding its value in the food web, but prior methods have lacked the required source specificity. We analyzed the H-Print index, based on biomarkers of ice algae versus phytoplankton contributions to organic carbon in marine predators, in Pacific walrus livers collected in 2012, 2014 and 2016 from …


Food/Non-Food Classification Of Real-Life Egocentric Images In Low- And Middle-Income Countries Based On Image Tagging Features, Guangzong Chen, Wenyan Jia, Yifan Zhao, Zhi-Hong Mao, Benny Lo, Alex K Anderson, Gary Frost, Modou L Jobarteh, Megan A Mccrory, Edward Sazonov, Matilda Steiner-Asiedu, Richard S Ansong, Thomas Baranowski, Lora Burke, Mingui Sun Jan 2021

Food/Non-Food Classification Of Real-Life Egocentric Images In Low- And Middle-Income Countries Based On Image Tagging Features, Guangzong Chen, Wenyan Jia, Yifan Zhao, Zhi-Hong Mao, Benny Lo, Alex K Anderson, Gary Frost, Modou L Jobarteh, Megan A Mccrory, Edward Sazonov, Matilda Steiner-Asiedu, Richard S Ansong, Thomas Baranowski, Lora Burke, Mingui Sun

Children’s Nutrition Research Center Staff Publications

Malnutrition, including both undernutrition and obesity, is a significant problem in low- and middle-income countries (LMICs). In order to study malnutrition and develop effective intervention strategies, it is crucial to evaluate nutritional status in LMICs at the individual, household, and community levels. In a multinational research project supported by the Bill & Melinda Gates Foundation, we have been using a wearable technology to conduct objective dietary assessment in sub-Saharan Africa. Our assessment includes multiple diet-related activities in urban and rural families, including food sources (e.g., shopping, harvesting, and gathering), preservation/storage, preparation, cooking, and consumption (e.g., portion size and nutrition analysis). …


Can The Circular Economy Concretize Sustainability? A Construal Level Approach To Encourage Sustainable Consumption., Jolie Gutentag Jan 2021

Can The Circular Economy Concretize Sustainability? A Construal Level Approach To Encourage Sustainable Consumption., Jolie Gutentag

Theses and Dissertations

Despite a growing awareness and understanding of the impact our lifestyles have on the environment, most people have not adequately changed their consumption patterns. One possibility for the disconnect is the perceived abstractness of sustainability. Drawing on construal level theory, this research proposes that framing environmental sustainability as circularity, using the principles of the circular economy, reduces the perceived abstractness of sustainability. Four studies investigate the effects of circular framing on sustainable consumption behavior, including the moderating role of consumers’ chronic level of construal, an innate mindset reflecting a tendency to view information more concretely or abstractly. Findings provide initial …


Streptococcus Sanguinis: The Good, The Bad, And The Metal-Binding Lipoprotein, Cody Murgas Jan 2021

Streptococcus Sanguinis: The Good, The Bad, And The Metal-Binding Lipoprotein, Cody Murgas

Theses and Dissertations

Streptococcus sanguinis is an opportunistic bacterium living beneficially in the human mouth. When S. sanguinis gains access to the bloodstream, it can result in colonization on damaged tissue and generate heart valve vegetations that can develop into infective endocarditis. It has been suggested that Mn and Fe are cofactors in the pathogenic capacity of this bacterium, and that these redox active metals are imported by the metal binding lipoprotein S. sanguinis adhesin B (SsaB). The SsaB lipoprotein is an integral part of SsaACB, an ATP-binding cassette (ABC) transport system in S. sanguinis. When SsaB is deleted, the resulting strain displays …


Diversity And Taxonomy Of Malagasy Pygmy Hippopotamuses, Allison Shackelton Jan 2021

Diversity And Taxonomy Of Malagasy Pygmy Hippopotamuses, Allison Shackelton

Graduate Research Theses & Dissertations

Madagascar has many species of extinct megafauna, including up to three species of extinct hippopotamus. Subfossil hippo specimens have been found at sites across Madagascar, yet the number of species and taxonomic relationships of the extinct Malagasy pygmy hippopotamus are poorly understood. This thesis will analyze cranial and postcranial bones to improve our understanding of the diversity and taxonomy of Malagasy subfossil hippos, focusing on adults from Ampasambazimba and Tsaramody and juveniles from Ampasambazimba and Anjohibe. Measurements of the tibia and femur of adult specimens, which are used as diagnostic features in other studies, may not be accurate diagnostic features, …


Evaluating And Predicting The Risk Of Algal Blooms In A Freshwater Lake Through A 4-Dimensional Approach: A Case Study On Lake Mitchell, Sumit Kumar Ghosh Jan 2021

Evaluating And Predicting The Risk Of Algal Blooms In A Freshwater Lake Through A 4-Dimensional Approach: A Case Study On Lake Mitchell, Sumit Kumar Ghosh

Electronic Theses and Dissertations

Excessive algal growth in freshwater lakes can negatively impact ecosystems, recreation, and human health. Though algae are a natural part of freshwater ecosystems, elevated nutrient loading from anthropogenic and natural sources can lead to algal blooms. Both algae and blue-green algae (BGA) are responsible for algal blooms; however, BGA (cyanobacteria) is more dangerous. The first objective of this research was to prepare a conceptual model to understand how various environmental variables affect algae. This conceptual model was used to choose the environmental variables that help increase or decrease algae in the water environment. The second objective was to develop empirical …


Quantifying Avoidable Food Waste And Identifying Its Underlying Causes: A Case Study Of A University Dormitory In Thailand, Shimpei Iwasaki, Suphat Prasopsin, Thamarat Phutthai Jan 2021

Quantifying Avoidable Food Waste And Identifying Its Underlying Causes: A Case Study Of A University Dormitory In Thailand, Shimpei Iwasaki, Suphat Prasopsin, Thamarat Phutthai

Applied Environmental Research

To develop well-planned and effective policies and programs for reducing avoidable food waste, it is important to quantify the actual food waste level in particular settings and assess relationships among consumers’ awareness, attitudes, and behaviors. Recognizing these considerations, this paper measured avoidable food waste generated by university students living in dormitory buildings and identified its underlying causes in the case of Kanchanaburi campus, Mahidol University, Thailand. The study applied a food waste composition survey 18 times between January and May 2019 while administering questionnaires in October 2019 to the dormitory students. Based on these measures, the study identified 1,417 instances …


Human Centeredness: The Foundation For Leadership-As-Practice In Complex Local/Regional Food Networks, Maryann Martinez Jan 2021

Human Centeredness: The Foundation For Leadership-As-Practice In Complex Local/Regional Food Networks, Maryann Martinez

Antioch University Dissertations & Theses

Our local and regional food systems are predominately modeled on a failed capitalist market-based economy. In the absence of corporate accountability, and/or support on the federal policy level, local and regional leadership and self-organized networks are critical to the scaling across and evolution of a moral and equitable food system. Networked food systems leaders are developing the capacity to solve wicked problems, and spark change. Understanding the values and practices of local food systems leadership that initiate, influence, and support activities is essential to understanding how to foster conditions for local and regional food network growth. My dissertation research is …


The Development Of A Procedure For The Pxrf Analysis Of Soil Cation Exchange Capacity In Collaboration With Colorado Farmers, Claire E. Wineman Jan 2021

The Development Of A Procedure For The Pxrf Analysis Of Soil Cation Exchange Capacity In Collaboration With Colorado Farmers, Claire E. Wineman

Senior Independent Study Theses

Discrepancies between farmers’ and scientists’ knowledge systems and experiences have long prevented the success and mutual beneficiality of collaborative research efforts between these two groups. The development of agricultural technologies, such as portable X-ray fluorescence (PXRF) for the analysis of soil cation exchange capacity in the field, creates a promising overlap point for farmers and scientists to cooperatively study issues within their sociocultural context and with access to institutional resources. In this study, the generation of an in-field PXRF method in collaboration with Colorado farmers helps to provide a prospective model for scientists and farmers looking to use collaborative research …


Health Risk Assessment Of Burmese Related To Consumption Of Heavy Metals Contaminated Fish From Local Market In Bangkok, Thailand, Myat Myitzu Jan 2021

Health Risk Assessment Of Burmese Related To Consumption Of Heavy Metals Contaminated Fish From Local Market In Bangkok, Thailand, Myat Myitzu

Chulalongkorn University Theses and Dissertations (Chula ETD)

Heavy metals contamination in human through the ingestion of contaminated fish may lead to serious health problems. This study was a cross sectional study conducted during February and March 2022 in Bangkok, Thailand. The objectives of this study were 1) to find the concentration of heavy metals contaminated in fish from local market in Thailand 2) to find the cancer risk and non-cancer risk of heavy metals from fish consumption. Face-to-face interview and online questionnaire were used to collect the personal information of 400 Burmese living in Bangkok. As, Cd, Cr, Pb, and Hg were analyzed by ICP-MS from four …


Safety Behaviour In Pesticide Use And Disposal Among Nigerian Cocoa Farmers, Oluseye Olalekan Oludoye Jan 2021

Safety Behaviour In Pesticide Use And Disposal Among Nigerian Cocoa Farmers, Oluseye Olalekan Oludoye

Chulalongkorn University Theses and Dissertations (Chula ETD)

Nigerian cocoa farmers are indiscriminately using and disposing pesticides in a manner that poses danger to their health and the environment. Thus, sequential explanatory mixed methods design was used to explore personal and environmental determinants of pesticide safety and disposal behaviours among the farmers. Using face-to-face interviews, 391 cocoa farmers were interviewed based on a reliable and valid questionnaire consisted of the health belief model (HBM), disposal practices and sociodemographic questions. In the qualitative phase, in-depth interviews were conducted among 23 cocoa farmers and 34 relevant stakeholders to further explore the factors influencing safe pesticide use and disposal using the …


Chemical Constituents Of Fan-Si Abutilon Indicum Stems, Arum Restu Widyasti Jan 2021

Chemical Constituents Of Fan-Si Abutilon Indicum Stems, Arum Restu Widyasti

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study aimed to isolate secondary metabolites from the stems of Abutilon indicum and to evaluate their α-glucosidase, pancreatic lipase, α-chymotrypsin inhibitory activity. Chromatographic fractionation of the n-hexane crude extracts led to the isolation of three known metabolite (1-3). The crude extract from all parts of the plant were evaluated for inhibitory activity on the alpha-glucosidase enzyme. The DCM-soluble roots were active with 10.2% at 25 μg/mL. The hexane and MeOH-soluble stems were active with 11.0% at 25 μg/mL and 8.0% at 0.25 μg/mL. The hexane, DCM, and MeOH-soluble leaves are active with 20.2% at 0.025 μg/mL; 20.0% at 0.025 …


Thin-Layer Chromatography For Determination Of Phenolic Compound Profile And Antioxidant Activity Of Thai Honey, Pattraporn Chobpradit Jan 2021

Thin-Layer Chromatography For Determination Of Phenolic Compound Profile And Antioxidant Activity Of Thai Honey, Pattraporn Chobpradit

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this study, a small-scale method using thin-layer chromatography (TLC) was developed to determine profile and antioxidant activity value of Thai honey samples obtained from different flora sources. Prior to TLC analysis, the samples were prepared by solvent extraction with dichloromethane. Using 2, 2-diphenyl-1-picrylhydrazy radical (DPPH•) reacted with the samples extract prior to TLC spot and color detection with imageJ, half-maximal inhibitory concentration (IC50) values of seven honey samples was obtained in a range of 9 to 22 mg/mL in comparison with IC50 values of 0.13 mg/mL for L-ascorbic acid (LA), along with limit of detection (LOD) and limit of …


Discrimination Of Weedy Rice By Using Near-Infrared Spectroscopy Combined With Chemometrics, Sureerat Makmuang Jan 2021

Discrimination Of Weedy Rice By Using Near-Infrared Spectroscopy Combined With Chemometrics, Sureerat Makmuang

Chulalongkorn University Theses and Dissertations (Chula ETD)

Weedy rice is one of the most notorious weeds occurring in rice-growing areas, especially in South-East Asia. Weedy rice especially in form of paddy seed is difficult to manage and separate as they provide common features (morphological resemblance) to cultivated rice. This work presents a modification of self-organizing map (SOMs) for the classification of weedy rice from cultivated rice via in situ direct sample analysis from paddy seed using near-infrared (NIR) spectroscopy and hyperspectral NIR camera. The sample pretreatment was carried out by a cyclone vacuum machine to remove the contaminated particles and other impurities. The physical characteristics and the …


Developing A System Of Community-Based Agritourism For Sustainable Local Food Systems: A Multi-Case Study Of Rural Livelihood Diversification And Sustainable Urban Consumption In City-Regional Bangkok, Sofia Anna Enrica Cavalleri Jan 2021

Developing A System Of Community-Based Agritourism For Sustainable Local Food Systems: A Multi-Case Study Of Rural Livelihood Diversification And Sustainable Urban Consumption In City-Regional Bangkok, Sofia Anna Enrica Cavalleri

Chulalongkorn University Theses and Dissertations (Chula ETD)

Current food systems fail to directly link rural producers and urban consumers. This research explores and categorizes emerging community-based agritourism practices as strategies to reconnect rural food producers with urban consumers. The main research question of this study is: how can community-based agritourism link rural food producers and urban consumers as a rural livelihood diversification strategy? Mixed methods for data collection were selected to answer this question and analyzed with a deductive and inductive approach. These include the review of secondary grey and academic literature, shadow observation in three rural provinces, content validity index calculation performed by experts (n = …


Changes In Surface Water And Sediment Quality At A Complex Tidal-Influenced River: A Case Study Of Ganh Hao River, Mekong Delta, Vietnam, Muoi Le Van Jan 2021

Changes In Surface Water And Sediment Quality At A Complex Tidal-Influenced River: A Case Study Of Ganh Hao River, Mekong Delta, Vietnam, Muoi Le Van

Chulalongkorn University Theses and Dissertations (Chula ETD)

The research was carried out to determine the extent of surface water and sediment pollution using the physicochemical parameters and heavy metal concentrations. The surface water and sediment samples were obtained from 25 sites along the river on March 22 and September 5, 2019 at the main river influenced by the complex tidal regime and aquaculture practices in Ca Mau peninsular in the Vietnamese Mekong Delta. The water quality was compared with international and national standards, while the sediment quality was compared with Vietnamese standards and pollution indices (geo-accumulation index, contamination factor, and pollution load index). Principal component analysis (PCA) …


Health Risk Assessment Of Toxic Metals In Commonly Consumed Salad Leafy Vegetables In Bangkok, Zin Htoo Hlyan Jan 2021

Health Risk Assessment Of Toxic Metals In Commonly Consumed Salad Leafy Vegetables In Bangkok, Zin Htoo Hlyan

Chulalongkorn University Theses and Dissertations (Chula ETD)

The objectives of this study were 1) to investigate concentrations of toxic metals including As, Cd, and Pb in the commonly consumed salad leafy vegetables which were sold in Bangkok, and 2) to assess potential human health risks of As, Cd, and Pb exposure via salad leafy vegetables consumption. A total of 120 samples were randomly collected from local fresh markets in Bangkok. The total concentrations of toxic metals were determined by an inductively coupled plasma mass spectroscopy (ICP-MS). Total concentrations of As, Cd and Pb in coral lettuce (CL), red coral (RC) and green oak (GO) for soil cultivation …


Production Of Bio-Olefins From Oleic Acidvia Oxidative Dehydrogenation Using Vanadium Oxides/Sba-15 Catalysts, Nattaporn Chaidherasuwet Jan 2021

Production Of Bio-Olefins From Oleic Acidvia Oxidative Dehydrogenation Using Vanadium Oxides/Sba-15 Catalysts, Nattaporn Chaidherasuwet

Chulalongkorn University Theses and Dissertations (Chula ETD)

Long-chain olefins (≥C10) are important commodity chemicals, which are primarily used to manufacture everyday products such as plastic packaging, surfactants and detergents in cleaning products, and lubricant oil additives. However, the long-chain olefins are currently synthesized from the petroleum refining process via ethylene oligomerization or thermal cracking of long-chain paraffins. To support the Bio-Circular-Green Economy (BCG) model, the direct synthesis of olefins from renewable feedstocks has become an attractive route to promote overall sustainability. The objective of this research was to study the possibility to transform oleic acid (OA), one of the unsaturated fatty acids in palm oil, to produce …


การศึกษาเชิงเปรียบเทียบของวิธีการสกัดน้ำมันจากเมล็ดเทียนดำโดยการอัดสกรูและคาร์บอนไดออกไซด์ภาวะเหนือวิกฤต, บัณฑิตา สกุลกิตติยุต Jan 2021

การศึกษาเชิงเปรียบเทียบของวิธีการสกัดน้ำมันจากเมล็ดเทียนดำโดยการอัดสกรูและคาร์บอนไดออกไซด์ภาวะเหนือวิกฤต, บัณฑิตา สกุลกิตติยุต

Chulalongkorn University Theses and Dissertations (Chula ETD)

นํ้ามันเมล็ดเทียนดำเป็นนํ้ามันหอมระเหยซึ่งถูกนำมาประยุกต์ได้อย่างกว้างขวางโดยเฉพาะด้านการแพทย์แผนโบราณ ในช่วงไม่กี่ปีที่ผ่านมาเทคโนโลยีการสกัดสะอาด (green extraction technology) ได้รับความสนใจใช้เป็นวิธีเลือกในการสกัดสารจากธรรมชาติ การสกัดด้วยคาร์บอนไดออกไซด์ภาวะเหนือวิกฤต (supercritical carbon dioxide) เป็นหนึ่งในทางเลือกที่น่าสนใจสำหรับการสกัดสารจากธรรมชาติ อีกทั้งแก๊สคาร์บอนไดออกไซด์ไม่เป็นพิษ ไม่ติดไฟ ไม่มีกลิ่น ไม่มีรส เฉื่อย และมีราคาถูก ในงานวิจัยนี้เป็นการศึกษาเชิงเปรียบเทียบของวิธีการสกัดนํ้ามันจากเมล็ดเทียนดำโดยการอัดสกรูและคาร์บอนไดออกไซด์ภาวะเหนือวิกฤตที่ภาวะต่าง ๆ ในช่วงความดัน 200 -300 บาร์และช่วงอุณหภูมิ 40 – 60 องศาเซลเซียส ที่อัตราการไหลของคาร์บอนไดออกไซด์คงที่ 10 กรัมต่อนาที นํ้ามันที่สกัดจากเมล็ดเทียนดำบดโดยใช้เฮกเซนเป็นตัวทำละลายมีปริมาณร้อยละ 40.20±1.41 โดยนํ้าหนัก นํ้ามันที่สกัดจากเมล็ดเทียนดำโดยการอัดสกรูมีปริมาณร้อยละ 25.41±1.20 โดยนํ้าหนัก ในขณะที่ยังมีนํ้ามันคงค้างเหลืออยู่ในกากเมล็ดเทียนดำถึงร้อยละ 20.88±0.51 โดยนํ้าหนัก นํ้ามันที่สกัดจากเมล็ดเทียนดำบดโดยคาร์บอนไดออกไซด์ภาวะเหนือวิกฤตพบว่าที่ความดัน 300 บาร์ อุณหภูมิ 50 องศาเซลเซียสเป็นภาวะเหมาะสมที่สุดที่สามารถสกัดเมล็ดเทียนดำบดได้ปริมาณนํ้ามันสะสมสูงสุดถึงร้อยละ 36.28 โดยนํ้าหนัก องค์ประกอบกรดไขมันที่พบในนํ้ามันเทียนดำบดส่วนใหญ่ประกอบด้วยกรดไขมันลิโนเลอิก กรดโอเลอิกและกรดปาล์มมิติก องค์ประกอบหลักทางเคมีที่พบในนํ้ามันหอมระเหยคือ เอ็ม-ไซมีน ไทโมควิโนน และลองกิโฟลีน


พอลิเมอร์ดูดซึมน้ำมากฐานพอลิอะคริลิกแอซิด/ไมโครคริสตัลลีนเซลลูโลสจากเส้นใยยางพารา, ทิพาพรรณ ดำเกาะ Jan 2021

พอลิเมอร์ดูดซึมน้ำมากฐานพอลิอะคริลิกแอซิด/ไมโครคริสตัลลีนเซลลูโลสจากเส้นใยยางพารา, ทิพาพรรณ ดำเกาะ

Chulalongkorn University Theses and Dissertations (Chula ETD)

พอลิเมอร์ดูดซึมน้ำมากถูกสังเคราะห์จากไมโครคริสตัลลีนเซลลูโลสและพอลิอะคริลิกแอซิดเป็นมอนอเมอร์ แอมโมเนียมเพอร์ซัลเฟตเป็นตัวริเริ่มปฏิกิริยา และเอ็น, เอ็น’-เมทิลีนบิสอะคริลาไมด์เป็นสารเชื่อมขวางเพื่อใช้เป็นตัวดูดซึมน้ำและน้ำปัสสาวะสังเคราะห์ ในงานวิจัยนี้ ไมโครคริสตัลลีนเซลลูโลสได้จากเส้นใยยางพาราที่ได้จากใบยางพาราสดและใบยางพาราแห้ง ผ่านกระบวนการเชิงกลและสารเคมี ศึกษาองค์ประกอบชีวมวลพืชด้วยวิธี Goering and Van Soest ลักษณะทางสัณฐานวิทยาด้วยกล้องจุลทรรศน์อิเล็กตรอนแบบส่องกราด หมู่ฟังก์ชันด้วยเทคนิคฟูเรียร์ทรานส์ฟอร์มอินฟราเรดสเปกโตรสโกปี ความเป็นผลึกด้วยด้วยการเลี้ยวเบนของ รังสีเอกซ์ และพฤติกรรมการสลายตัวเชิงความร้อนด้วยการเปลี่ยนแปลงน้ำหนักอาศัยสมบัติทางความร้อนของไมโครคริสตัลลีนเซลลูโลส ผลการทดลองพบว่าไมโครคริสตัลลีนเซลลูโลสที่ได้จากเส้นใยยางพาราสดและเส้นใยยางพาราแห้งมีลักษณะและสมบัติคล้ายกัน ดังนั้นไมโครคริสตัลลีนเซลลูโลสที่ได้จากเส้นใยยางพาราแห้งถูกนำมาเตรียมพอลิเมอร์ดูดซึมน้ำมากผ่านกระบวนการ พอลิเมอไรเซชัน ศึกษาผลของปริมาณของไมโครคริสตัลลีนเซลลูโลสและสารเชื่องขวางในการสังเคราะห์พอลิเมอร์ดูดซึมน้ำมากที่มีผลต่อการดูดซึมน้ำและน้ำปัสสาวะสังเคราะห์ นอกจากนี้ตรวจสอบหมู่ฟังก์ชัน เปอร์เซ็นต์การกราฟต์ และสมบัติเชิงความร้อนของพอลิเมอร์ดูดซึมน้ำมาก พอลิเมอร์ดูดซึมน้ำมากที่เตรียมจากไมโครคริสตัลลีนเซลลูโลสร้อยละ 25 ของกรดอะคริลิกแอซิดที่สารเชื่อมขวางร้อยละ 0.05 ของกรดอะคริลิกแอซิด ให้ค่าดูดซึมน้ำและน้ำปัสสาวะสังเคราะห์สูงถึง 203 ± 0.67 g/g และ 53 ± 0.75 g/g ตามลำดับ แสดงให้เห็นว่าพอลิเมอร์ดูดซึมน้ำมากที่สามารถดูดซึมน้ำและน้ำปัสสาวะสังเคราะห์ สามารถเตรียมได้จากใบยางพาราซึ่งเป็นวัตถุดิบจากธรรมชาติ


ฟิล์มคอมพอสิตของสโคบีเซลลูโลส/ไฮโดรไลซ์คอลลาเจนเคลือบด้วยไคโตซานสำหรับประยุกต์เป็นแผ่นปิดแผล, พันธิตรา ยาแก้ว Jan 2021

ฟิล์มคอมพอสิตของสโคบีเซลลูโลส/ไฮโดรไลซ์คอลลาเจนเคลือบด้วยไคโตซานสำหรับประยุกต์เป็นแผ่นปิดแผล, พันธิตรา ยาแก้ว

Chulalongkorn University Theses and Dissertations (Chula ETD)

สโคบีแบคทีเรียลเซลลูโลสเป็นพอลิเมอร์ที่มีความเข้ากันได้ดีทางชีวภาพเนื่องจากมีสมบัติที่หลากหลาย ได้แก่ มีความบริสุทธิ์สูง สมบัติเชิงกลที่ดี การดูดซึมน้ำที่ดี และความไม่เป็นพิษซึ่งทำให้เหมาะสมสำหรับการประยุกต์ใช้เป็นวัสดุปิดแผล ในงานวิจัยนี้ทำการเตรียมฟิล์มจากการผสมสโคบีเซลลูโลส/ไฮโดรไลซ์คอลลาเจนที่อัตราส่วน 90:10, 80:20 และ 70:30 โดยน้ำหนัก โดยเติมกลีเซอรอลร้อยละ 5 โดยน้ำหนักลงไปเพื่อเป็นพลาสติไซเซอร์ หล่อแบบจนแห้งหลังจากนั้นเคลือบด้วยละลายไคโตซานร้อยละ 1 โดยน้ำหนักต่อปริมาตร วิเคราะห์และทดสอบความเข้ากันได้ของฟิล์มด้วยเทคนิค FTIR, SEM และ TGA จากผลการทดสอบยืนยันว่าชั้นไคโตซานเคลือบทับสโคบีแบคทีเรียลเซลลูโลสจากการเกิดอันตรกิริยาระหว่างกันด้วยพันธะไฮโดรเจน การทดสอบสมบัติต้านแบคทีเรียทดสอบกับเชื้อ S.aureus บ่งชี้ให้เห็นว่า บริเวณยับยั้งการเจริญของเชื้อบริเวณฟิล์มที่เคลือบไคโดซานมีสมบัติต้านแบคทีเรียได้ดีกว่า นอกจากนี้ทำการบรรจุแอสคอร์บิคแอซิดลงในฟิล์มคอมพอสิตโดยทำการแช่ลงในสารละลายแอสคอร์บิคแอซิดในสารละลายฟอสเฟตบัฟเฟอร์ pH 7.4 เป็นเวลา 12 ชั่วโมง โดยวิเคราะห์ปริมาณยาสะสมที่ถูกปลดปล่อยออกมาโดยเทคนิค UV-Vis spectroscopy บ่งชี้ให้เห็นว่าฟิล์มคอมพอสิตไม่เพียงแต่กักเก็บรูปออกฤทธิ์ของแอสคอร์บิคแอซิดแต่ยังสามารถควบคุมการปลดปล่อยของแอสคอร์บิคได้อีกด้วย ดังนั้นฟิล์มคอมพอสิตที่วิจัยขึ้นนี้สามารถนำมาประยุกต์ใช้เป็นวัสดุปิดแผลที่เติมสารออกฤทธิ์ลงไปได้


Investigating Predation Risk Experienced By Wintering Birds At A Supplied-Food Garden, Madison Smart Jan 2021

Investigating Predation Risk Experienced By Wintering Birds At A Supplied-Food Garden, Madison Smart

Department of Environmental Studies: Undergraduate Student Theses

Wintering birds are particularly susceptible to predation while foraging at feeders. The ‘starvation vs. predation’ survival trade-off is felt most acutely in winter because energy demands are higher compared to milder seasons. This study investigated sense of predation risk experienced by members of a wintering mixed-species flock. The objective was to determine which species take on increased predation risk in order to forage at feeders, and if there was bias for one species over another. A raptor (experimental) and non-raptor (control) model were presented to a mixed-flock at feeders within Pioneers Park Nature Center. The first species to return to …


Live Cell Biomass Tracking For Basic, Translational, And Clinical Research, Graeme Murray Jan 2021

Live Cell Biomass Tracking For Basic, Translational, And Clinical Research, Graeme Murray

Theses and Dissertations

Single cell mass is tightly regulated throughout generations and the cell cycle, making it an important marker of cell health. Abnormal changes in cell size can be the first indication of dysfunction in response to environmental stimuli such as cytotoxic drugs. Described here is the further development of high-speed live cell interferometry (HSLCI) to concurrently measure the changes in single cell mass of thousands of cells over time. Critically, the high-throughput nature of HSLCI provides realistic pictures of tumor heterogeneity. This throughput enabled HSLCI to correctly predict in vivo carboplatin sensitivity of three triple negative breast cancer patient derived xenografts, …