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Hidden Layer Reshaping on Convolutional Neural Network
No full textArtificial Intelligence (AI) technologies have become really popular in recent years. From ChatGPT to Tesla cars, many applications can benefit from these type of technologies. Automotive, healthcare, biomedical, cybersecurity, finances, and retail are some of the fields that take advantage of it. It has been seen that AI can solve complex problems, but there is still work to be done to optimize it. A deep learning neural network (DLNN) tries to simulate how a human brain operates. These DLNNs are made up of artificial neurons which are connected by weight that are modified when the network is trained. These networks are used to create AI technologies like the ones mentioned before. Computer vision is another of those areas that benefits greatly and it is the focus of this research. Computer vision tries to mimic human vision by enabling computers, devices or machines to understand, interpret or manipulate what is being seen. DLNNs help with tasks such as classification, object detection, tracking, and image manipulation which are all part of computer vision. The research focuses on optimizing a Convolutional Neural Network (CNN). These types of networks are commonly used when the input data for the neural network are images. The network filters the images and down samples them to make it more manageable when handling the large amount of data incoming from them. The specific layer of interest to improve is the hidden layer. There is not a set number of neurons to be used for this layer, so different approaches will be used to compare accuracy and training time of the network
Early non-psychotic deviant behavior in schizophrenia: a possible endophenotypic marker for genetic studies
No full textHow to Share a Success, How to Share a Crisis, and How All This Is Related to Fuzzy
No full textIn many practical situations, a group of people needs to share a success. What is the fair way to share this success? Nobelist John Nash showed that under reasonable conditions, the group should select the alternative for which the product of utility gains is the largest possible. This solution makes perfect sense from the fuzzy-formalized commonsense viewpoint: it maximizes the degree of confidence that all participants are happy. A natural question is: can we extend this result to a different class of situations, when a group of people needs to share sacrifices caused by a crisis? In this paper, we prove that in this case, no solution satisfies the same set of conditions. We also explain how to actually fairly distribute needed sacrifices in the case of a crisis
Thermal Inkjet Bioprinting Of Human Fibroblasts Into Stem Cell Environment Leads To Stem-Like Gene And Protein Expression And Changes In Hippo Pathway Effectors Yap/taz
No full textThermal inkjet bioprinting (TIB) has emerged as a powerful tool with many potential applications, such as organ regeneration, drug testing, and cell differentiation, among others. Despite the forces and stress that cells are subjected to during the printing process, there is little research that investigates in detail the combined effects of the TIB process and the surrounding environment on cells. Furthermore, a cell\u27s biological environment greatly influences its behavior. Therefore, understanding the effects of bioprinting on cells in a particular environment at a genetic level can provide clues regarding changes in cell characteristics. Bioprinting could potentially be used as a tool for reprogramming or differentiation into different cell types. We hypothesize that using a thermal inkjet bioprinter to bioprint human fibroblasts into induced pluripotent stem cell (iPSC) media will stress the cells, induce disruption of their membranes, and encourage them to upregulate stem-cell-related genes and proteins in response to their environment. Apart from assessing TIB-related changes in gene and protein expression, this work also assesses changes seen in the Hippo pathway effectors YAP/TAZ, as nuclear localization of these has been shown to have positive effects in reprogramming to pluripotency.In this study, we investigated changes in thermal inkjet bioprinted human dermal fibroblasts printed into a stem cell environment using different techniques. We performed immunocytochemistry to assess changes in stem related proteins, lamin A/C, and Hippo pathway effectors. RNA sequencing analyses were conducted at different time points to assess changes in gene expression dynamics at different time points. Finally, DNA methylation studies and analyses on DNA integrity were conducted to examine the impacts of TIB on DNA. Results from RNA sequencing experiments showed differential expression of genes involved in pluripotency-relevant pathways and upregulation of some genes associated with stemness. Immunocytochemistry experiments revealed increases in stem cell markers, particularly for the earlier stem cell marker Lin28b in bioprinted cells, which was particularly prominent at the 24-hour time point post-printing. Analysis of YAP and TAZ localization behavior revealed increased nuclear expression of both YAP and TAZ in TIB cells compared to control cells. Further analyses on YAP dynamics as a result of TIB revealed that stresses on the cell during the TIB process could be influencing YAP phosphorylation at serine 128 and allowing it to enter the nucleus. Finally, DNA methylation analysis revealed decreases in DNA methylation right after printing. The results of this study reveal fundamental changes in gene and protein expression that should be taken into account when using TIB cells in other experiments and that could be used to our benefit to develop new methods of cell engineering and cell reprogramming
The Feast And The Furious? The Effects Of Diet On Opioid Tolerance, Withdrawal, And Stress
No full textIntroduction: Opioid drugs (e.g., morphine) are used medicinally for pain relief but can also lead to opioid use disorder (OUD). These medications are prescribed at a higher rate among individuals with obesity (who might consume high fat diets) than the general population. Further, previous work from our lab and others has demonstrated that eating a high fat diet enhances sensitivity of rats to other addictive substances, including stimulants. However, it is not known if dietary manipulations impact individual sensitivity to the effects of opioids. This dissertation systematically explored the effects of dietary manipulation on sensitivity to the effects of morphine. Aim 1 evaluated behavioral sensitivity to acute and chronic morphine among rats eating different diets and Aim 2 evaluated the effects of dietary manipulations and chronic morphine on metabolic factors, stress, and sex hormones using behavioral and physiological methods. It was hypothesized that eating a high fat/high carbohydrate diet would increase tolerance to morphine\u27s antinociceptive effects and that eating a ketogenic diet would reduce withdrawal severity. It was further hypothesized that food restriction would enhance tolerance and have no effect on withdrawal severity as compared with rats with free access to diets. Finally, we hypothesized that these expected diet-induced differences in opioid tolerance and withdrawal would be mediated by diet-induced alterations in metabolic markers, as well as sex and stress hormones. Methods: Male Sprague-Dawley rats (n=7-8 per dietary group used in both aims) were randomly assigned to either free or restricted access to a low fat chow, a high fat/high carbohydrate chow, or a high fat/low carbohydrate (ketogenic) chow. Rats were injected with saline or doses of morphine (0.32-56 mg/kg, IP) to assess nociception, antinociception, and tolerance over a 6-week period using the warm water tail withdrawal procedure. To assess hyperalgesia, paw biting was measured immediately after warm water tail withdrawal procedures during the bottle brush test. To assess withdrawal following chronic morphine administration, naltrexone (17.8 mg/kg, SC) was administered to precipitate withdrawal, and up to 14 withdrawal signs (i.e., wet dog shake, ptosis, teeth chattering, paw tremors, chromodacryorrhea, lacrimation, and diarrhea) and weight loss were observed. To assess reward, sensitization was measured from morphine-induced locomotor activity (0.32-10 mg/kg, IP). To assess constipation (using a separate group of rats; n=8/group), fecal boli were measured hourly for 6 hours following an injection of saline or morphine (1, 3.2, or 10 mg/kg, IP) in rats with free access to a low fat chow, a high fat/high carbohydrate chow, or a ketogenic chow. To assess affective pain, facial coding of grimace features was measured using the Rat Grimace Scale (RGS), and to assess stress, aggressive and defensive behaviors were measured using the bottle brush test. Testosterone, corticosterone, ketones, and leptin were measured from serum using ELISA kits. Results: There were no dietary group differences in the antinociceptive effects of acute morphine; however, rats with free access to high fat/high carbohydrate chow developed greater tolerance to the antinociceptive effects of morphine as compared to the other dietary groups. In contrast, morphine-induced hyperalgesia was increased among rats with restricted access to high fat/high carbohydrate chow or restricted access to ketogenic chow than rats with free access to low fat chow. Naltrexone precipitated withdrawal in all rats; however, rats with free or restricted access to ketogenic chow displayed fewer withdrawal signs and lost less withdrawal-related body weight than rats with free access to low fat chow. Further, rats with free access to a high fat/high carbohydrate or ketogenic chow regained weight at a faster rate than the other dietary groups. Further, there were no dietary group differences regarding morphine-induced locomotion, and sensitization was observed at only one test. Morphine induced constipation in all groups; however, rats with access to a high fat/high carbohydrate or ketogenic chow produced less feces than rats with access to a low fat chow following injections of saline or morphine. There were no meaningful dietary group differences in aggressive or defensive behaviors, RGS scores, or grooming behavior; however, defensive and RGS scores were greater for all rats during chronic morphine and withdrawal testing as compared to acute morphine testing. Rats with restricted access to chows had smaller concentrations of testosterone than rats with free access; however, corticosterone concentrations were comparable among rats eating different diets. Rats with free access to high fat/high carbohydrate chow or ketogenic chow had significantly greater leptin concentrations than the other dietary groups. Further, rats with free or restricted access to ketogenic chow had significantly greater concentrations of β-hydroxybutyrate than the other dietary groups. Conclusion: These results demonstrate that dietary factors can impact the effects of morphine, including tolerance, hyperalgesia, constipation, and withdrawal severity. Further, these data suggest that eating a high fat/high carbohydrate diet enhances opioid tolerance, whereas a ketogenic diet mitigates the severity of morphine withdrawal. These results have implications for considering nutritional factors when developing personalized pain management strategies to reduce risk factors associated with OUD
Optimal Accelerated Life-Testing Plans Under Progressive Type II First Failure Censoring Scheme
No full textDesigning optimal accelerated life testing (ALT) plans under progressive Type-II first failure censoring involves complex computational challenges, especially when trying to balance efficiency, precision, and practicality. This research introduces a novel optimization framework aimed at determining the best test configuration that minimizes estimation uncertainty within constrained experimental conditions. We developed a tailored meta-heuristic strategy based on an enhanced Variable Neighborhood Search (VNS) algorithm, which efficiently navigates the complex landscape of censoring schemes and stress allocations. Unlike conventional methods that typically focus on simpler censoring or stress-level structures, this approach simultaneously optimizes both the censoring points and sample allocations across various stress levels in an accelerated testing context. The proposed method prioritizes maximizing the determinant of the Fisher Information Matrix under D-optimality, ensuring minimal variance in parameter estimation. Extensive simulation studies demonstrate the robustness and computational efficiency of the algorithm, showing significant improvements over traditional techniques, particularly in large-scale ALT scenarios. Furthermore, the framework takes into account real-world constraints such as limited test durations and maximum allowable censoring, enhancing its practical applicability. This work advances the field by extending optimal test plan methodologies to more realistic censoring schemes, providing a powerful decision-support tool for reliability engineers and researchers in accelerated life testing environments
Development Of Porous Separators For Lithium-Ion Batteries Via 3d Printing And Thermally Induced Phase Separation
No full textAdditive manufacturing processes allow the development of custom-shape rechargeable batteries, but research in custom filaments for fused deposition modeling (FDM) of battery separators has remained limited until now. This study discusses the development and optimization of a composite thermoplastic filament feedstock to 3D print separator membranes. A number of post-processing steps - leveraging the thermally induced phase separation (TIPS) of the composite filament - are introduced in tandem with FDM to promote microporosity formation through the removal of the sacrificial diluent phase within 3D printed samples. Three distinct compositions of varying polymer/diluent ratios were developed and thoroughly investigated through thermogravimetric analysis, differential scanning calorimetry, scanning electron microscopy, rate capability cycling testing, linear sweep voltammetry, potentiostatic electrochemical impedance spectroscopy, X-ray micro-computed tomography, and tensile testing to explore the need for a compromise between porosity, electrochemical performance, printability, and mechanical strength. Results revealed a trend where increasing polymer content led to improved tensile strength and printability, but electrochemical performance in coin cell batteries was compromised. These findings introduce a novel process to manufacture porous separator membranes without mechanical post-processing and highlight the promising electrochemical performance of 3D printed separators. Understanding the influence of printing parameters during TIPS enables better control over pore size and distribution, further improving electrochemical performance of 3D printed separators
Three Essays On Entrepreneurial Orientation And Competitive Repertoire
No full textWhile scholars confirm the positive relationship between entrepreneurial orientation (EO) and firm performance with meta-analyses, the mixed findings with widespread effect sizes imply that this critical relationship in entrepreneurship literature deserves further inspection. In this three-essay dissertation, I integrate the entrepreneurial orientation literature with the competitive repertoire literature. Specifically, in essay 1, I develop a theoretical framework of EO, competitive repertoire, and firm performance through the lens of capability theory. In the second essay, I examine the moderating role of competitive pressure on the EO-competitive repertoire relationship with a sample of all U.S.-listed firms. Finally, I articulate and examine how competitive repertoire mediates the relationship between EO and firm performance in the third essay. My dissertation contributes not only to EO literature but also to competitive repertoire literature in several ways
Navigating Spaces: Understanding LGBTQ+ Families Who Homeschool Amid Shifting Legislative And Societal Landscapes
No full textThis qualitative case study explored the motivations and lived experiences of caregivers of LGBTQ+ youth who chose homeschooling amid escalating anti-LGBTQ+ legislation in the United States. Guided by Self-Determination Theory (SDT) (Deci and Ryan, 1980) and Queer Theory (Chevrette, 2013), the study examined how caregivers navigated educational decisions to construct affirming, identity-conscious learning environments in response to exclusionary policies and systemic marginalization. Data was collected through semi-structured interviews with four caregivers residing in politically conservative states in the U.S.. The findings revealed that homeschooling functioned both as a protective measure against institutional harm and as a proactive strategy for fostering inclusive, community-based educational spaces. The study introduces the concept of Familial Queer Counterspaces to describe intentional learning environments centered on affirmation and belonging. Findings from this work highlights the need for further research focused on LGBTQ+ youth and caregivers in nontraditional educational settings
BIM Assessment for State Departments of Transportation
No full textBuilding Information Modeling (BIM) has been used by the Architecture, Engineering, and Construction (AEC) industry to enhance the efficiency and quality of work across various stages, including planning, design, construction, and operation and maintenance (OM) of projects. Despite widespread adoption in vertical construction, BIM implementation in infrastructure projects is still falling behind. This disparity can be attributed to several factors, including the complexity and scale of infrastructure projects and varying levels of BIM adoption and integration within organizations. Efforts to standardize BIM practices and enhance the digital capabilities of infrastructure projects are essential to bridge this gap and ensure the industry can benefit from the efficiencies and improvements that BIM offers. This study aims to assess BIM maturity at the organizational level for transportation agencies. The BIM Maturity Index (BMI) sub-elements were grouped based on existing literature and mapped to the National Strategic Roadmap published by the Federal Highway Administration (FHWA) to standardize the terms used in evaluating BIM maturity. A survey questionnaire and BIM maturity tool was developed and administered to several state departments of transportation to assess the current state of BIM implementation in those states. The results indicate that BIM use is still in the initial stages for many of the sub-elements of the BIM Maturity Index and that a lack of standardization of terms remains the most significant challenge among transportation agencies