TTU Published Journals @ Volpe Library
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Determination of the Radius of Fibrin Fibers for Wound Healing Applications Via the Carr-Hermans Method
Get PDFThe quantitative description of the structure of the biopolymer fibrin has implications in wound healing. As for any protein, the structure and morphology of fibrin is essential to its function and is conjectured to control specific aspects of the wound healing process. The wound healing process is comprised of four phases. During the initial stages of wound healing, fibrinogen and thrombin are introduced to the wound site to interactively produce fibrin fibers that provide a scaffolded structure for the wound environment [N. Laurens et al.]. As the wound healing process progresses, the fibrin fibers are enzymatically degraded and collagen fibers take the place of fibrin, ultimately resulting in the healed tissue after continued remodeling of the structure [JC Chaplin, KA Hajjar]. This enzymatic degradation of the fibrin fibers is termed fibrinolysis, a process which affects the breakdown of fibrin clots at a wound site and henceforth the healing of the skin and scarring of the tissue surrounding the wound site. The rate of breakdown of fibrin strands is affected by their structure, the thickness of the fibers being one factor affecting this process [DA Gabriel et al.]. This reveals the need for a procedure to determine the radius of the fibrin strands. This contribution will communicate a flowchart that guides one through the steps of acquiring and analyzing data to apply the Carr-Hermans Method, which leads to an estimate of the radius of the fibrin strands
General Overview of Wastewater Treatment Process with Special Focus on Secondary Treatment Method
Get PDFWastewater is used water that comes down the drains from buildings such as household, factory, school, or offices and includes sources like showers, sinks, dishwasher, toilet, etc. It contains substances from various sources including organics, medicine, and several other substances like toilet paper, cleaning & personal products that are harmful to the environment. It also contains diverse trophic level of microorganisms such as protozoans, fungi, and varieties of bacteria (aerobic, anaerobic, and facultative). Therefore, a treatment facility needs to be equipped with several processes and unit operations so that a complete decontamination can take place before water is released to the natural environment. Each unit operation in a wastewater treatment plant (WWTP) is associated with mechanical, physical, biological, and chemical aspects of cleaning.This contribution is focused on reviewing these general cleaning processes and operations and identifying connections with fundamental principles in engineering. Thus, we are looking for appropriateness of employing more effective and efficient variations associated with the biological processes (activated sludge). The aim is to develop an environment to mimic the naturally occurring microbiology and biochemistry in the human system during the metabolic breakdown of these chemicals and biopharmaceuticals. The secondary treatment is identical to a metabolic type of biological reactor that can be modelled and optimized. The targeted outcome is to identify the key factors controlling the metabolic degradation and make potential observations helpful to increase the degradation efficiency. Our study could be potentially useful for the design of a more efficient and better maintained treatment
*WINNER* Electrotherapeutic Assisted Wound Healing: Modelling of the Electrostatic Field in a Porous Gel or Healing Media
No full textAmong the many advances in the biomedical sciences in the last decade, the bio-mathematical foundation to homeostatic wound healing deserves further attention in the scientific community. Recent new contributions (Jorgensen, 2017) have made progress experimentally in understanding transport of biomedicines in hydrogels of potential use as an effective scaffolding material to facilitate wound healing. In addition, work has been done (Oyanader et al, 2020) to increase the understanding of the electro-convective-diffusive transport of biomolecules in wound healing in electrotherapeutic assisted wound healing applications, theoretically. This contribution will focus on the modeling of the electrostatic electrical field effects in the wound microenvironment of the scaffolding material by using idealized pore domains to describe pore morphology. The driving interest of our study is to understand the effects of the electrokinetic forces on the diffusion and migration of thrombin to induce the conversion of fibrinogen to fibrin, as this would be one of the initial steps in the early-phases of the wound healing process. Specifically, the electrostatic Laplace equation, in a pore domain of cylindrical geometry, will be solved via the use of area-averaging methods and its solution will be parametrically illustrated for a set of values of the applied voltages. The role of material, scale, and electro-migration on the transport of bio nutrients and medicines via the use of the molar species continuity equation will be discussed. Future steps in the research project will be highlighted
Electromagnetic camouflage through a multi-layer metamaterial structure
No full textStealth technology plays an important role in the security of our country. In order to gain information on an enemy we must be able to conduct surveillance without being detected. This means that we need to continue to develop stealth technology in order to keep up with the modern devices in object detection and tracking. There are two main methods used for object detection and tracking, which are IR and Radar detection. The IR method detects infrared band frequencies produced by the object and the Radar method relies on microwave band frequencies reflecting off of the object. In order to create stealth against the IR detectors we need to decrease the amount of IR radiation that is emitted from the object. This requires materials that have very low emissivity and therefore high reflectivity. This creates a problem for radar stealth though. For radar stealth the object needs low reflectivity and high absorptivity so that the radar wave is not reflected back. This makes it difficult to create a stealth material that is effective for both IR and Radar detection systems. The solution may be found in the creation of engineered metamaterials, which have a unique property of negative refractive index, unlike materials that are found in nature. My research is related to creating a multi-layer structure comprised of different metamaterials. These meta-structures will act like filters for different frequencies and aid in the creation of IR and Radar stealth structures that are extremely important for electromagnetic camouflage
Development of three directional three-dimensional composite dentures with short glass fiber reinforced methyl methacrylate using fused filament fabrication process
Get PDFFiber reinforced additive manufacturing (FRAM) is becoming a subject of great interest in dentistry as it offers opportunities that could be explored in the dental field concerned with the “design and manufacture” of devices. Herein, we evaluated the practicality of FRAM for constructing patient specific and affordable composite denture bases with improved mechanical and clinical properties: polymethylmethacrylate (PMMA) as matrix was reinforced with short glass fibers (SGFs) using the fused filament fabrication (FFF) process. Representative parts for this study, were built with different layer heights (0.2, 0.1, 0.05 mm) and volume fractions (0%, 2.5%, 5%) in three mutually perpendicular directions (0˚ in X-Y plane, 90˚ in X-Y plane, and 90˚ in Z axis), and analyzed for surface roughness (resolution) and mechanical properties (tensile, flexural, compressive properties). Mechanical properties were influenced significantly by printing direction, layer height, and volume fractions; in general, parts with lower layer heights and higher SGFs reinforcement constructed in 0˚ in X-Y plane showed improved mechanical properties and good surface finish. Additional scanning electron microscopy was performed to study the effect of fiber distribution, fiber breakage, fiber accumulation and the adhesion at the interface of the PMMA/SGFs composite materials. The practical implications of the study at a “proof of concept stage” are low-cost manufacturing of highly accurate, lightweight and affordable medical devices with enhanced patient comfort in the long term and improved clinical properties particularly for geriatric use.
Keywords: Fiber reinforced additive manufacturing, Fused filament fabrication, Denture base, Composite, layer height, surface roughnes
The Aerodynamic Effects of a Battle-Damaged Wing
No full textThe aerodynamic effects of battle-damaged wings were investigated using a six-axis torque sensor in a wind tunnel at low Reynolds numbers. Two 3D printed NACA-4409 wings were used for this study. Both wings had a chord length of 8 inches, with the span of the first wing being six times the chord length and the span of the second wing being three times the chord length. The holes used for the study were 16.67 percent (1.34 inches) and 25 percent (2 inches) of the chord length, respectively. The holes were placed along both the leading and trailing edges to investigate the sensitivity of the wing’s aerodynamic performance to the chordwise location of the damage
Force Analysis of Leg Muscles in Genus Panthera
No full textMimicking biology in mechanical systems, while no longer a new solution to design problems, does indeed allow for innovation compared with traditional design. Biological systems are often highly efficient and can offer engineers a blueprint to create from. For example, members of the genus Panthera, (lions, tigers, leopards, jaguars, and snow leopards), defined here as “big cats”, are naturally optimized for speed and power in killing prey. They are apex predators yet still maintain balance and stealth as they hunt. The goal of this project is to analyze the muscular structure of the legs in big cats from a mechanical force analysis. The five big cats will be compared graphically based on average size, food consumption, muscle mass, muscle distribution, relative speed, and strength. Computational algorithms describing the mathematical model of motion of each component of the muscle system will be developed. Variables of interest will be identified and tested, hypothesizing to see what combination of graphed characteristics creates the strongest/fastest/lightest/most fuel-efficient system. This information can then be applied to the design of a machine as a mechanical system prototype inspired by the given characteristics and the basic structure of a big cat’s leg
*WINNER* Impedance-based NDE through Instrumented Fixtures; Effects of Clamping Force on Defect-detection Capabilities
No full textElectromechanical impedance measurements allow for a rapid assessment of structural integrity by providing insights into its dynamic response. Several studies have shown that electromechanical impedance signatures obtained via directly bonded piezoelectric transducers can be used for non-destructive evaluation of manufactured parts. Indirect electromechanical impedance measurements, through an instrumented testbed, have also been introduced as a promising solution for a rapid evaluation of manufactured parts. While such indirect impedance measurements alleviate the need for individual parts to be instrumented, they increase the complexity of the measurement system. Factors such as fixture design, part-fixture interface, and clamping force are found to impact measurement sensitivity to manufacturing defects and anomalies.
In this study, the effect of clamping force between the instrumented fixture and the part under test on indirect electromechanical impedance measurements is investigated. A steel fixture is instrumented with macro-fiber composite piezoelectric transducers for electromechanical impedance measurement. Clamping force is measured using calibrated strain gauges. Defect-free machined steel blocks (controls) and blocks featuring manufacturing defects are selected as the test specimens. Electromechanical impedance signatures of the specimens are measured using Zurich Instruments MFIA impedance analyzer and then compared with the signature of the control specimens. Finally, the sensitivity of impedance signatures to manufacturing defects is evaluated at various clamping force levels, and recommendations are presented
*WINNER* Communicating Corona: How Science Can Harness New Media during a Pandemic
No full textThe COVID-19 pandemic has presented a major challenge to public health and the field of technical communication across the globe: how can medical experts quickly and effectively convey their highly specialized knowledge in ways that instruct, inform, and persuade non-specialists when infection rates are rising? In Germany, two instances of new media—a podcast series titled “Das Coronavirus-Update” and the YouTube channel “maiLab”—demonstrate how scientists can quickly engage audiences and thereby have a major impact on public health. Informed by central principles of technical communication, such as purpose, audience, and situation, this project investigates the ways in which this podcast and YouTube channel successfully build trust and rapport while still managing to impart scientific knowledge in a professional, impactful, yet accessible manner. Although each genre features scientists sharing their hyper-specialized knowledge, these modern forms of communication manage to effectively instruct and inform their audience by considering the audience’s needs and the special circumstances surrounding the production of the medium. This project was created for a Directed Studies in German course with a focus on Technical Communication in the age of COVID, where I use my Technical and Professional Communication skills to explore how Germany handled the pandemic
The correlation between homelessness and child development
No full textAlthough the United States is a first world country, there is still a concern about homelessness among today’s youth and the consequences that may come from it. The most prevalent group of those that are homeless continues to be families with children, and it is still growing. Is there a correlation between child development and child homelessness? This adverse experience affects all areas of children’s development including physical, cognitive, and psychosocial, and those consequences are likely to follow them through life. The goal of this research is to explore the different developmental delays a child who is homeless may have and the different adverse experiences that might be a risk factor for it. Using keywords like child development and homelessness in different databases, a literature search was conducted to identify the research already available about child development and homelessness. Research has shown that children who are homeless are more likely to have a physical disability of some kind, as well as test academically below their peers who are not homeless. Some research has focused on the psychosocial domain which has shown children who are homeless may lack that social connection because of instability, and in turn alienates them from the rest of their peers. This has been a trend amongst most research with some not acknowledging the room for resilience which is prevalent in children. However, children who experience homelessness are more likely to have a delay in one or more developmental domains