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Determination of Fibrin Fiber Diameter Using Scanning Electron Microscopy and Image Processing Software
Get PDFInjectable, biodegradable scaffolds that mimic local tissue properties have great potential for aiding and accelerating the natural wound healing process. Ideally, scaffolds will have physical properties e.g., stiffness and microstructures, that are comparable to the tissue in which they will be applied. Fibrin is an insoluble protein that is formed in vivo during hemostasis via action of the enzyme thrombin on the soluble protein fibrinogen. It acts as a glue that holds together a loose platelet plug - a blood clot - that is degraded as wound healing progresses. The stiffness of this material can be easily tuned by adjusting its composition, as has been previously shown. These combined factors make fibrin a suitable scaffolding candidate for promoting cell delivery to wound sites, cell growth, and proliferation which are important parameters influencing the healing process. Scanning electron microscopy as well as other techniques are currently being leveraged in order to better understand fibrin's microstructure. Fibrin hydrogels are prepared in vitro by mixing fibrinogen, thrombin, and CaCl2 at various compositions. After additional processing, samples are then dried using either critical point drying or freeze-drying techniques to retain structure, and are subsequently sputter coated with gold/palladium, and imaged using a Hitachi SU7000. A MATLAB script was created that allows for the random selection and analysis of fibers. The resulting image is transferred into ImageJ where fiber sizes are measured. Average fiber diameter for fibrin gels prepared using fibrinogen at 6mg/ml and thrombin at 1U/ml is estimated to be 77nm
*WINNER* Modeling the Removal of Cosmetic Dyes by Using Hydrogel Materials in a CSTR
No full textDyes, or their degradation products in water, can cause various human health disorders including but not limited to hemorrhage, ulceration of skin and mucous membranes, and severe damage to the kidney. Even trace amounts of dye in effluent is highly undesirable due to its pollutive effects. Treatment methods for wastewater that are currently pursued include biological treatments, coagulation, ion exchange, and membrane filtration. While there is a considerable amount of research for textile dye effluent wastewater treatment, toxic dyes produced by cosmetic and personal care industries remain yet to be investigated.
The current state of knowledge about treatment of wastewater from the cosmetics industry is poor, which is evidenced by the number of publications on the subject. A number of adverse health effects from cosmetic dyes have been reported, such as birth defects, brain damage, and environmental pollution. Therefore, it is important to address this growing concern within the cosmetic industry. It has been widely hypothesized that adsorption is an efficient method for dye removal in wastewater, and hydrogel beads are efficient adsorbents for this purpose. In this research project, a liquid-solid phase, continuous-stirring tank reactor (CSTR) is modeled via volumetric and area-averaging approaches to derive the up-scaled reactor equation. The model applies for the case of treating wastewater with cosmetic dyes, where adsorption takes place on the surface of the hydrogel beads, extracting these toxic dyes. Key aspects of the upscaling process with illustrative results will be presented and future work outlined
Solid Oxide Fuel Cell Combustor Gas Turbine Hybrid Power System for Commercial Electric Aircraft
Get PDFCommercial aviation is a vital part of modern society. In 2018, commercial aviation was responsible for 2.4 percent of the total global carbon dioxide emissions and these numbers are expected to triple by 2050. This percentage seems relatively low, but if the commercial aviation industry was considered a country in the national carbon dioxide emission standings, it would rank sixth in the world. The addition of carbon neutral aviation provides a method to lower the carbon dioxide and greenhouse gas emissions caused by current methods of air travel. The proposed solution is to create an electrically powered aircraft that has a net zero carbon emission, and can match the performance of current commercial aviation. A solid oxide fuel cell combustor gas turbine hybrid system (SOFCC-GT) is a viable option to provide an aircraft with enough power for full operation. SOFCs utilize an onboard hydrocarbon fuel and ambient air to produce electricity through electrochemical reactions and typically operate between 650oC – 850oC. The proposed SOFCC-GT will be capable of generating 24 MW of electrical power for the aircraft. The electrical power will be utilized by the propulsion, avionics, and all other electrical systems used in modern commercial aircraft. To validate the SOFCC-GT system, steady state and transient modeling will be used to simulate the system operation under various flight conditions. Pressurized testing of an SOFCC system will be completed and studied to evaluate the power densities generated by the SOFCs and to increase the fidelity of the system models
Misconceptions of Sustainability within the Luxury Fashion Industry
Get PDFThere is an extreme contrast between fast fashion and designer fashion, but ironically they are both leaders in the fashion industry. This research is an examination of how fast fashion brands and designer brands are integrating sustainable and ethical practices into their designs within the industry. Fast fashion is the reinvention of slow fashion that encourages disposability and thrives on fast cycles constantly bringing in the newest trends, where luxury fashion is a much slower form of design, centered around three main themes: dreams, exclusivity, and beauty/art (Joy, Sherry, Venkatesh, Wang, & Chan, 2012). One of the biggest differences between fast fashion and slow fashion is that creating luxury products takes time, limiting availability, and not mass-producing. In return, this actually slows the fashion cycle, reducing the amount of waste associated with creating fashion products. However, without a clear understanding of what consumers should look for when shopping for more sustainable fashion brands, this all can become overwhelming. This research will explore the disconnect in consumers’ knowledge regarding the sustainability within the luxury fashion industry
Is there a relationship between child abuse and child development?
Get PDFChild abuse is a problem that is still going on in society. Many children suffer from child abuse which has consequences that can be drastic to their development. Is there a relationship between child abuse and child development? In this project I will explore the types of child abuse. This should give an understanding of the consequences that it can have on child’s mental, emotional, and social development. There is need to raise awareness about it. Since some parents might not know the difference between a punishment and when it becomes abuse. The aim is to bring awareness to the effects of child abuse on a child’s development. One group uses logistic regression to find the relationship of child abuse and adult health risk behaviors. The other group compares eighty-seven abused children to eighty-seven non-maltreated classmates. One study collected saliva samples from school age maltreated and non-maltreated children. Some of the research was also conducted in classrooms. In other instances, children and mothers were interviewed. The information gathered in the classroom was to investigate behavioral problems witnessed by teachers. Research shows that family violence can have an effect on social development for children especially when it comes to peers. Also, that child abuse can have an effect on a child’s behavior and mental health. The awareness of child abuse to parents and the community can help in reducing the risks that it has on a child’s development. This can improve the health of many children in the long term
The Effects of Corn Ear Declination on Waterfowl Forage Availability in Unharvested Flooded Corn Fields
Get PDFManaging for non-breeding waterfowl throughout the winter requires managers to provide enough forage resources to meet the energetic demands of waterfowl recovering from autumn migration, maintaining body condition during winter, and preparing for spring migration. During the winter months (November to March), waterfowl species, such as the mallard (Anas Platyhrynchos), rely on calorie-dense food sources to meet their energetic demands. Many waterfowl species readily consume agricultural seeds, such as corn (Zea mays), grain sorghum (Sorghum bicolor), millet (Echinochloa spp), soybeans (Glycine max), and rice (Oryza spp), to fulfill their energetic requirements. In western Tennessee, public and private land managers often flood unharvested corn fields to provide forage for wintering waterfowl. The availability of forage within unharvested flooded corn fields is affected by several factors including distance of corn ear to water and ear declination. We measure foraging intensity, ear distance to water and ear declination by repeatedly surveying 30 unharvested, flooded corn fields in western Tennessee at two-week intervals throughout the winter (October-March). The analysis is ongoing and will be done before poster presentations. We hope that by determining the factors influencing forage availability we will allow wetland managers to improve forage availability for wintering waterfowl
Exploring Goodwill Impairment in Relation to Covid-19 and Critical Audit Matters
Get PDFIn 2019, Auditing Standard 3101 began requiring Critical Audit Matters (CAM) to be included in Auditors Reports. A CAM is any matter arising from the audit of the financial statements that has been communicated or is required to be communicated to the audit committee, and that relates to accounts or disclosures that are material to the financial statements, and that involves especially challenging, subjective, or complex auditor judgments. Goodwill impairment was identified as a CAM for many companies in 2019 and 2020. I examined the auditor's reports for 36 public companies that reported goodwill impairment for the period impacted by the Covid-19 pandemic, from March 2020 to December 2020. Within this sample, Auditors issued 45 CAMs total, including 19 CAMs for goodwill. I examined the footnotes to determine whether restrictions and/or lockdowns imposed due to the pandemic were mentioned as causes of the impairment. A majority of them cited a decline in demand for their products/services and/or a decline in market capitalization as factors that led to testing goodwill for impairment. I examined the determining factors for inclusion in the Auditor's Report as a CAM. My analysis suggests that a CAM for goodwill impairment is more likely when the size of the impairment relative to goodwill is large and when the company is audited by a Big 4 accounting firm. Regression analysis indicates that CAMs are less likely for companies with international segments
Multilingual Toxic Comment Classification
No full textWith the growth of the Internet and data collection in the last twenty years, we have seen a rise with Internet Relay Chats (IRC) as well, especially in 2020 due to COVID. Now more than ever, it is important that we stay connected despite being physically separated and to make sure communications systems are as inclusive as ever. Our goal in this project is to categorize toxic comments used in IRC chat rooms and forum pages via a machine learning model in order to keep communications safe and welcoming to the public. We define toxicity as any message that is rude, disrespectful, or otherwise likely to make someone leave a discussion. If these toxic contributions can be identified, we could have a safer, more collaborative internet. As a result of our models, we will be able to identify a dataset of toxic comments with at least a 70% success rate. Additionally, we want to be able to successfully identify both new and previously existing comments as toxic or non-toxic in multiple languages that others have previously label incorrectly. Using a dataset provided by Kaggle, we demonstrate how we are able to detect if a Wikipedia talk page comment is toxic (scored as a 1) or non-toxic (scored as a 0) by using statistical methods, data analysis, and various data science approaches
Predicting Damage Based on Gorkha Earthquake Dataset
No full textEarthquakes like the 2015 Gorkha earthquake in Nepal can cause massive damage to buildings in immediate and surrounding areas. It is important to people in those areas to be prepared for the possibility of such destruction to their structures. One way for those people to be prepared is to be able to predict the degree that buildings will be affected. We set out to predict the variable damage_grade in the dataset, which represents a level of damage to the building that was hit by the earthquake – low, medium, or complete destruction. Based on aspects of building location and construction, we developed a predictive model based on an initial exploratory analysis using descriptive statistics. We utilized R Studio, Python, and other software to construct our predictive model, create visuals, and compile a report of our findings
Synthesis of TiO2-CdS Photocatalyst for Photocatalytic Degradation of Carbamazepine and Photocatalytic Water Splitting for Hydrogen Production in Waste Water Using Solar and Artificial -UV Radiation
No full textAdvanced oxidation processes, in particular, semiconductor photocatalysis, are useful methods for contaminants’ removal from wastewater including pharmaceuticals, organic chemicals, and microbial disinfection. Furthermore, the technique is beneficial for hydrogen production by photocatalytic splitting of water. The optimization of this technology for simultaneous degradation of carbamazepine, hydrogen production and upscaling for its large-scale implementation is still a big challenge for environmental engineers. This research is focused on fostering understanding and new knowledge of novel photocatalytic materials for the simultaneous elimination of water contaminants and hydrogen production. It is well known that titanium dioxide semiconductor photocatalyst is readily available, environmentally safe, and possesses significant photocatalytic activity for water decontamination. However, it is photo-responsive only in the ultraviolet region (Eg 3.2 eV) that comprises only 4% of the solar spectrum falling on Earth. Therefore, there is a need for the synthesis of a new photocatalyst or, alternatively, the modification of the TiO2 for a cost-efficient visible light responsive photocatalytic material that is suitable for the dual purpose indicated above. This research focuses on developing a general technique to synthesize three different types of photocatalysts such as titanium dioxide (TiO2), cadmium sulfide (CdS), and cadmium sulfide doped titanium dioxide (TiO2/CdS) for the preliminary testing of the degradation of carbamazepine (CBZ) under visible and UV radiation. For the characterization of the catalyst materials, scanning electron microscopy and X-ray diffraction (XRD) instrumentation will be used. Comparisons with current literature values for results’ validation will be included and the steps for future research will be highlighted