Modeling Thin Layers in Material Response Solvers

Thermal Protection Systems (TPS) are a necessary component for atmospheric entry. Most TPS contain thin layers of various materials such as ceramic coatings, pore sealers and bonding agents. When modeling TPS, these thin layers are often neglected due to the difference in scale between the TPS (centimeters) and the thin layers (micrometers). In this study, a volume-averaging flux-conservation method is implemented in the governing equations of a finite volume material response code. The model proposes the addition of a volume and area fraction coefficient which utilizes a weighted-averaging between the amount of thin layer and heat shield material in a given cell. A verification case shows that the new model is capable of capturing physics of a thin layers of materials without additional computational costs. The model is also applied to heat conduction and porous flow to show that the volume-averaging flux-conservation model is effective at capturing the physics without adding additional computational cost

A Green Chemistry Experiment: Magnetic Citrate Alginate Hydrogels Remove Methylene Blue from Water

The objective of this research was to design a green chemistry experiment that synthesizes magnetic citrate alginate hydrogels and test their effectiveness for the removal of methylene blue (MB) dye. Methylene blue dye is a common water pollutant that is toxic, carcinogenic, and nonbiodegradable; thus, can cause a severe threat to human health and environmental safety. Hence, there is a need to develop an environmentally friendly, efficient technology for removing MB from wastewater.https://scholarworks.moreheadstate.edu/celebration_posters_2023/1035/thumbnail.jp

Watching Aggressive, Attractive, Female Protagonists Shapes Gender Roles for Women Among Male and Female Undergraduate Viewers

The impact of exposure to media representations of aggressive, attractive, female protagonists on audiences’ gender role expectations for women was explored through a laboratory experiment with 122 undergraduates from a large university on the west coast of the United States. Participants viewed a segment of a major Hollywood motion picture that featured a female protagonist who was either highly attractive or less attractive and either highly aggressive or not aggressive. Viewing clips featuring a female protagonist who was both aggressive and stereotypically attractive led to greater endorsement of stereotypically feminine and stereotypically masculine gender role expectations for women. The effect on endorsement of stereotypically masculine expectations was partially mediated by the perception that the protagonist was a good role model for women. Although women endorsed both feminine and masculine gender role expectations for women more strongly than men, the effects of exposure to aggressive, attractive, female protagonists were similar for both male and female participants. Results are discussed in terms of gender stereotype activation and superwoman expectations for women

Usability of myfood24 Healthcare and Mathematical Diet Optimisation in Clinical Populations: A Pilot Feasibility Randomised Controlled Trial

Monitoring nutritional intake is of clinical value, but few existing tools offer electronic dietary recording, instant nutritional analysis, and a platform connecting healthcare teams with patients that provides timely, personalised support. This feasibility randomised controlled trial tests the usability of ‘myfood24 Healthcare’, a dietary assessment app and healthcare professional website, in two clinical populations. Patients were recruited from a weight management programme (n21) and from a group of gastroenterology surgery outpatients (n = 27). They were randomised into three groups: standard care, myfood24, or myfood24 + diet optimisation (automated suggestions for dietary improvement). The participants were asked to record their diet at least four times over eight weeks. During the study, healthcare professionals viewed recorded dietary information to facilitate discussions about diet and nutritional targets. The participants provided feedback on usability and acceptability. A total of 48 patients were recruited, and 16 were randomised to each of the three groups. Compliance among app users (n = 32) was reasonable, with 25 (78%) using it at least once and 16 (50%) recording intake for four days or more. Among users, the mean (standard deviation) number of days used was 14.0 (17.5), and the median (interquartile range) was six (2.5–17.0) over 2 months. Feedback questionnaires were completed by only 23 of 46 participants (50%). The mean System Usability Score (n = 16) was 59 (95% confidence interval, 48–70). Patient and healthcare professional feedback indicates a need for more user training and the improvement of some key app features such as the food search function. This feasibility study shows that myfood24 Healthcare is acceptable for patients and healthcare professionals. These data will inform app refinements and its application in a larger clinical effectiveness trial

Investigation of age related changes in porcine cortical bone with a focus on reference point indentation

This thesis focuses on reference point indentation (RPI) as a method to determine age related changes in porcine cortical bone. RPI uses a reference probe that sets the zero position for a test probe, which indents samples over a number of cycles. Various polymers and porcine cortical bone have been utilized to further understanding of the RPI technique. The goal of this research is to use this novel equipment to determine differences in mechanical properties of bones, specifically young porcine bones. While RPI is the main technique used in this study, it has been supplemented by techniques such as scanning electron microscopy (SEM), three-point bend tests, nanoindentation, computed tomography (CT) scans, and bone material strength (BMS) measurements made using the Osteoprobe, a clinical indentation device. This thesis is comprised of three separate studies. The first study in this thesis analyzes the RPI testing procedure using six month porcine cortical bone with the intent of developing a standard test procedure. The RPI outputs were analyzed as a function of force magnitude, preconditioning, variation within a sample and between samples, number of cycles, indentation surface (transverse versus longitudinal, polished versus unpolished), and micro-computed tomography radiation exposure. SEM was used as support for the choice of force magnitude. The next study in this thesis is an investigation into the connection between RPI measurements, Osteoprobe measurements and known material properties of nine polymers. Eight 3D printed polymers and a standard polymer included with the RPI test machine were tested using both RPI and the Osteoprobe. These results were then compared to each other as well as the polymers’ known material properties. The final part is the main study of this thesis. In this study, age related changes in porcine cortical bone were analyzed using RPI as well as several other experimental techniques. This study used porcine bones obtained from animals of 0 to 20 weeks of age at four week intervals, resulting in six separate age groups evenly spaced throughout the animal’s early developmental stages. Tests used to determine the age related changes were three-point bend tests, nanoindentation, CT scans, RPI measurements and BMS measurements

Assessment of Newborn Resemblance by Parents and Newborn Recognition Abilities of Unrelated Individuals

Men are unsure of paternity because fertilization is internal. Because there is a lack of paternal assurance, mothers may be selected to increase paternity in order to assure that the father will invest in the child. One way that the mother could increase this assurance is to declare, at the birth of the child, that the baby resembles the father. Over a period of six months, 187 mothers were interviewed and were asked whom their babies most resembled. It was found that mothers remarked resemblance to the father more often than expected by chance. It was also found that fathers do not ascribe resemblance to one parent more than the other. Selected pictures of these same mothers, fathers, and babies were also analyzed by unrelated volunteers in the form of a survey. These volunteers were asked to match a baby to its correct mother and father. The results of this study indicated that males and females are equally able to match babies to the correct parents. It was shown that babies can be matched to parents more often than due to chance. It was also shown that babies are not matched with fathers more easily than with mothers. Considering both the interview and survey results, it was shown that resemblance assessment of mothers is not associated with actual resemblance. I suggest that mothers do ascribe resemblance to fathers more often than due to chance in order to increase paternal assurance

Correlation of Multi-scale Modeling and Experimental Results for the Elastic Modulus of Trabecular Bone

Trabecular bone is a porous nanocomposite material with a hierarchical structure. In this study, a multi-scale modeling approach, addressing scales spanning from the nanometer (collagen-mineral) to mesoscale (trabecular bone) levels, was developed to determine the elastic moduli of trabecular bone. Then, the predicted modeling results were compared with experimental data obtained by compression testing of bovine femur trabecular bone samples loaded in two different directions; parallel to the femur neck axis and perpendicular to that. Optical microscopy, scanning electron microscopy and micro-computed tomography techniques were employed to characterize the structure and composition of the samples at different length scales and provide the inputs needed for the modeling. To obtain more insights on the structure of bone, especially on the interaction of its main constituents (collagen and mineral phases), trabecular bone samples were deproteinized or demineralized and, afterwards, tested mechanically in compression. The experimental observations were used, in turn, to fine-tune the multi-scale model of bone as an interpenetrating composite material. Good agreement was found between the theoretical and experimental results for elastic moduli of untreated, deproteinized, and demineralized trabecular bones