Transport Mechanisms in Electrochemical Immunoassay Biosensors with Applications to SARSCOV-2 Neutralizing Antibody Detection

Biosensors are used in diverse applications spanning from clinical diagnosis and drug discovery to environmental and safety monitoring. Among different types of biosensors, electrochemical ones have demonstrated high sensitivity, short detection time, and selectivity with a low cost, and have been widely used to detect various diseases. In this thesis, we have introduced an inexpensive, rapid, sensitive, and quantifiable impedance-based immunosensors to evaluate SARS-CoV-2 neutralizing antibody (NAb), which shows the real protective immunity against COVID-19. We demonstrated that our device enabled assessment of NAb in a physiological buffer with conductivity equivalent to that of blood plasma. This technique can be used to evaluate NAb in people\u27s blood serum from 50 ng/ml to 190 ng/ml before receiving further COVID vaccine doses. We further analyzed Joule heating induced transport phenomena as a potential method to increase detection in electrochemical biosensors. Buoyancy-driven and AC electrothermal (ACET) flows are the main transport mechanisms that induce two competing flows. Using a scaling analysis, we introduced a new non-dimensional parameter, which enabled the construction of a phase-diagram that can predict the dominance of ACET and buoyancy driven flows as functions of the channel size and electric field

Microstructural evolution during hot deformation of duplex stainless steel

The microstructure evolution during hot deformation of a 23Cr-5Ni-3Mo duplex stainless steel was investigated in torsion. The presence of a soft &delta; ferrite phase in the vicinity of austenite caused strain partitioning, with accommodation of more strain in the &delta; ferrite. Furthermore, owing to the limited number of austenite/austenite grain boundaries, the kinetics of dynamic recrystallisation (DRX) in austenite was very slow. The first DRX grains in the austenite phase formed at a strain beyond the peak and proceeded to &lt;15% of the microstructure at the rupture strain of the sample. On the other hand, the microstructure evolution in &delta; ferrite started by formation of low angle grain boundaries at low strains and the density of these boundaries increased with increasing strain. There was clear evidence of continuous dynamic recrystallisation in this phase at strains beyond the peak. However, in the &delta; ferrite phase at high strains, most grains consisted of &delta;/&delta; and &delta;/&gamma; boundaries.<br /

Biaxial Wrinkling of Thin-Walled GFRP Webs in Cell-Core Sandwiches

Fiber-reinforced polymer (FRP) sandwich structures offer several advantages compared to structures made of traditional materials, such as high specific strength, good corrosion resistance, low thermal conductivity and rapid component installation. In this context, glass fiber-reinforced polymer (GFRP) cell-core sandwiches composed of outer GFRP face sheets, a foam core and a grid of GFRP webs integrated into the core to reinforce shear load capacity are well suited for load-bearing applications in civil engineering i.e. in bridge deck and roof construction. Despite the great potential of these structural concepts, the use of heterogeneous materials in FRP sandwiches results in more complex failure mechanisms compared to conventional structural components and lack of knowledge regarding the prediction of failure modes makes the design of structural components difficult. This is one of the major disadvantages limiting the acceptance of cell-core sandwiches in civil engineering applications. One of the critical failure modes of cell-core sandwich structures is wrinkling in the webs. A great deal of information exists concerning the phenomenon of skin wrinkling failure of sandwich laminates loaded in compression but comparatively little on wrinkling in the webs of sandwich structures where the pure compression loading is complicated by supplementary transverse tension. The purpose of this research is to develop an appropriate model for the prediction of wrinkling in the webs of cell-core sandwich structures. Two new approaches were developed to predict the wrinkling loads of webs. The first approach examines the wrinkling behavior in webs as an in-plane biaxial compression-tension buckling problem according to the rotated stress field theory. In this regard, extensive experimental, numerical and analytical studies were performed to investigate the interaction between the compression and tension stress tensors during the buckling/wrinkling instability phase of GFRP plates and sandwich panels subjected to biaxial compression-tension loading. The investigations demonstrated that the transverse tension in the biaxial compression-tension set-up induced two simultaneous counteracting effects: a stabilizing and a lateral contraction effect. The stabilizing effect tends to push the plate back to the median plane and thereby delays the onset of buckling/wrinkling instability. In contrast, lateral contraction accelerates the bending of the plate, which leads to a significant decrease in buckling/wrinkling loads. In composite plates, the first effect predominates and increases the buckling loads while in sandwich panels the second effect is dominant and decreases the wrinkling loads. Using the second approach, the wrinkling behavior of foam-filled web-core panels was modeled by applying an improved mixed-mode interaction formula in which two approximate models are developed based on the energy method in order to determine the critical loads when the pure shear and bending stresses act independently on the web. The application of both approaches to a real case study, the GFRP cell-core sandwich roof of the Novartis Campus Main Gate Building proved that they are sufficiently accurate to be used as valid tools assisting the optimum design of sandwich structures whereas existing models result in too conservative predictions

A case report of hearing loss post use of hydroxychloroquine in a HIV-infected patient

The Republic of Ireland, like many other countries is trying to diversify energy sources to counteract environmental, political and social concerns. Bioethanol from domestically grown agricultural crops is an indigenously produced alternative fuel that can potentially go towards meeting the goal of diversified energy supply. The Republic of Ireland’s distribution of existing soils and agricultural land-uses limit arable crop land to around 10% of total agricultural area. Demand for land to produce arable crops is expected to decrease, which could open the opportunity for bioethanol production. Bioethanol production plants are required to be of a sufficient scale in order to compete economically with other fuel sources, it is important therefore to determine if enough land exists around potential ethanol plant locations to meet the potential demands for feedstock. This study determines, through the use of a developed GIS based model, the potential quantities of feedstock that is available in the hinterlands of nine locations in the Republic of Ireland. The results indicate that three locations can meet all its feedstock demands using indigenously grown sugarbeet, while only one location can meet its demands using a combination of indigenous wheat and straw as the two locally sourced feedstocks.Department of Agriculture, Fisheries and Food Research Stimulus Fun

Simulation of dynamic recrystallization using irregular cellular automata

Computer simulation is a powerful tool to predict microstructure and its evolution during dynamic recrystallization. Cellular Automata (CA), as one of the most efficient methods proposed to simulate recrystallization and grain growth. In this work, recrystallization and grain growth phenomena were modelled by using a two dimensional irregular CA method. Initial grain size, nuclei density and orientation of each grain were variables which have been used as entering data to the CA model. Final grain size, orientation of each grain, dislocation density and stress-strain curve were the results which have been resulted to validate the current model. Considering the model assumptions, it is shown that the CA can successfully simulate dynamic recrystallization

Effect of microstructural morphology on the mechanical properties of titanium alloys

Different morphologies of α+β microstructures were obtained in a commercial Ti-6Al-4V alloy by cooling at different rates from the single β-phase region into the two phase region. The effect of such morphologies on mechanical properties was studied using hot compression tests in a Gleeble thermomechanical simulator. A variety of complex morphologies could be obtained since the cooling rate has a significant influence on the β to α phase transformation and the resulting morphological development. While most of the β phase transformed to colonies of α at high cooling rates, it was possible to obtain a complex mixture of a colonies, grain boundary a and lamellar structure by decreasing the cooling rate. These complex morphologies each exhibited distinctive mechanical properties and characteristic dynamic phase transformation behaviour during deformation as a function of strain rate

Postural and Musculoskeletal Disorders in Women with Urinary Incontinence: A Research Report

Introduction: To investigate and compare the prevalence of some postural and musculoskeletal disorders in women with and without Urinary Incontinence (UI). Urinary Incontinence (UI) is one of the most important social and health problems in women. Limited studies have shown that UI prevalence is around 35%-55% in Iran. Nevertheless, to the best of our knowledge, there is no exact and reliable data reported in the literature on the prevalence of musculoskeletal, postural, or other related disorders in UI patients in Iran. Methods and Materials: The current study was conducted based on the data obtained from 166 incontinent and 90 continent women attending Vali-e-Asr University Hospital between 2010 and 2012. After collecting participants’ demographic information, postural status was assessed. In addition, we measured values for pelvic inclination and lumbar lordosis angles. Finally, vaginal tone and pelvic floor muscle strength and endurance were evaluated. Kolmogorov-Smirnov (K-S) goodness-of-fit, Independent t, X2, and Pearson correlation tests were used for the purposes of data analysis. Results: The prevalence of low back pain, chronic pelvic pain, and pelvic asymmetry were significantly higher in incontinent women compared with that in continent women (p&lt;0.05). It was found that lumbar lordosis was significantly different between the two groups (P=0.021); however, no significant difference was observed regarding pelvic inclination (P=0.20). Conclusion: The present study confirms the hypothesis that incontinent women have higher prevalence of low back and pelvic pain and pelvic asymmetry. It is recommented that further epidemiologic and comprehensive etiologic investigations be conducted on these findings.Keywords: Urinary Incontinence, Posture, Musculoskeletal Disorders, Wome

Comparative analysis of machine learning and numerical modeling for combined heat transfer in Polymethylmethacrylate

This study compares different methods to predict the simultaneous effects of conductive and radiative heat transfer in a Polymethylmethacrylate (PMMA) sample. PMMA is a kind of polymer utilized in various sensors and actuator devices. One-dimensional combined heat transfer is considered in numerical analysis. Computer implementation was obtained for the numerical solution of governing equation with the implicit finite difference method in the case of discretization. Kirchhoff transformation was used to get data from a non-linear equation of conductive heat transfer by considering monochromatic radiation intensity and temperature conditions applied to the PMMA sample boundaries. For Deep Neural Network (DNN) method, the novel Long Short Term Memory (LSTM) method was introduced to find accurate results in the least processing time than the numerical method. A recent study derived the combined heat transfers and their temperature profiles for the PMMA sample. Furthermore, the transient temperature profile is validated by another study. A comparison proves a perfect agreement. It shows the temperature gradient in the primary positions that makes a spectral amount of conductive heat transfer from a PMMA sample. It is more straightforward when they are compared with the novel DNN method. Results demonstrate that this artificial intelligence method is accurate and fast in predicting problems. By analyzing the results from the numerical solution it can be understood that the conductive and radiative heat flux is similar in the case of gradient behavior, but it is also twice in its amount approximately. Hence, total heat flux has a constant value in an approximated steady state condition. In addition to analyzing their composition, ROC curve and confusion matrix were implemented to evaluate the algorithm performance.Comment: 15 pages, 11 figure