Neuronal Migration: How Do You Build a Brain?

Senior biology major Alex Burkard is working in the Walsh Neurodevelopment Laboratory at VCU to help answer the question, ‘How do you build a brain?’ Burkard is researching neuronal migration in Zebrafish and how cellular polarity affects hindbrain development

Lead Exposure in Children through Water and Soil

Lead is a metal which has the ability to spread in the earth’s crust and has corrosive property. It is a naturally occurring metal which is soft in nature. Lead exposure in children is through various pathways and the major concentrated sources are the soil and drinking water. Children are most susceptible to lead exposure is due to their growing/developing bodies which are very sensitive to lead. Lead poisoning in children is a preventable environmental disease affecting many children around the world. This paper discusses how soil and water plays a major role in lead exposure to children’s routine life. The adverse effects of lead poisoning range widely from delayed to severe health outcomes. According to the Center for Disease Control and Prevention (CDC) the blood lead levels should be no higher than 5µg/dl, which is considered as the new reference value. The epidemiological studies in the article details some statistical evidence that how children are affected by lead exposure through soil and water. Animal behavioral studies are mentioned in order to compare the toxic levels to humans. Even though there has been decline in the blood lead levels in children from 1970’s, very small amounts of blood lead can also result in various health outcomes. These blood lead levels in children are due to the lead based paints in old houses and the service lines made by lead and lead solder. Due to some regulatory interventions by the state and federal agencies the developed countries have reduced the lead exposure to an extent, but the developing countries are still at greatest concern in childhood lead poisoning

Organophosphates in Chlorpyrifos Insecticide: Neurobehavioral Development of Children in Agricultural Communities

The chemicals found in fertilizers and pesticides are known to adversely affect the human nervous system even at low levels of exposure. Neither the agricultural industry nor the EPA can deny scientific findings regarding the toxic qualities of organophosphates in the insecticide chlorpyrifos, but that does not deter pesticide manufacturers from selling harmful products. In fact, Dow AgroSciences, a pesticide company, states on its website that, “Insecticides, such as chlorpyrifos, provide important protection for our food supply and thus safeguard farm and consumer economy.” To understand the health risks associated with pesticide exposure, I studied the influence of organophosphates in the insecticide chlorpyrifos on children living in agricultural communities, primarily in Salinas Valley, California. I performed the review by analyzing a variety of articles and academic sources that focused on organophosphate exposure and child neurobehavioral functioning. The findings indicate that organophosphates found in the insecticide chlorpyrifos block the enzyme acetylcholinesterase and initiate the accumulation of the neurotransmitter acetylcholine, leading to impairments in attention and cognition. Farm children exposed to the chemicals via the mother during gestation period or who are exposed through inhalation or physical contact may be at higher risks for ADHD and autism than reference children who are typically only exposed to organophosphates through diet. Further study is needed to understand gender-based effects following organophosphate exposure. It is only through understanding the damaging effects of chemicals in pesticides that policies can be constructed to effectively reduce pesticide application and encourage alternatives of crop rotation, intercropping, crop diversity, and the use of pests to fight pests in the agricultural society.https://scholarscompass.vcu.edu/uresposters/1162/thumbnail.jp

Anxiety Reactivity in Monozygotic Twins Discordant for Major Depression

Transient anxiety is a healthy response to stress. However, constant anxiety elicits negative responses and threatens an individual’s day-to-day living. The onset of anxiety disorders excluding specific phobias is often childhood to late adolescence or early adulthood. Though depression is characterized as a low-energy state unlike anxiety, there is a high concordance between anxiety and depression. “Nearly one-half of those diagnosed with depression are also diagnosed with an anxiety disorder” (“Facts and Statistics”). There are two goals of the study: 1. To compare the individual response levels between monozygotic (MZ) twins discordant for major depressive disorder (MDD) during an anxiety-provoking task. 2. To evaluate the relationship between self-report measures and physiological responses in adolescent MZ twins discordant for MDD. To identify how physiological responses vary between MZ twins discordant for major depression during a resting baseline and the 7.5% carbon dioxide (CO2) breathing challenge task. The data was analyzed using multiple statistical methods including paired samples t-test and correlational models. We expected that MDD affected twins would self-report greater distress in response to an anxiety-provoking laboratory challenge and exhibit reduced physiological arousal. MDD affected twins demonstrated a somewhat reduced skin conductance response during the anxiety provoking task, suggesting blunted physiological response, which is consistent with other biological markers such as cortisol. There was a significant increase in sympathetic-vagal heart variability rate during the physiological baseline for the MDD affected twins. Although we did not observe any statistically significant differences for SUDS ratings assessed during baseline or inhalation of 7.5% CO2 enriched air, MDD affected twins reported higher levels of distress during the recovery period compared to their MDD unaffected co-twin. The results will shed light on the lasting impact of major depression on physiologic and subjective measures during rest and the biological challenge.https://scholarscompass.vcu.edu/uresposters/1160/thumbnail.jp

Optimization of the Single Point Active Alignment Method (SPAAM) with a Random Forest for accurate Visual Registration

The research addresses the visual calibration of head-mounted displays such as the HoloLens. The HoloLens is an optical see-through viewing device that allows a user to experience the real world populated with virtual objects. These virtual objects need to be correctly aligned with physical objects in the environment to experience a visually appropriate scene. However, several factors, such as an outside-in tracking system, tracking errors, the user\u27s eye position, and others degrade the alignment between the virtual and physical object. A popular calibration method to correct this misalignment is the so-called Single Point Active Alignment Method (SPAAM) [1]. It allows one to improve the alignment by measuring and correcting the alignment error. Nonetheless, one encounters alignment errors since, SPAAM assumes a constant error between the physical object, the display, and the user\u27s eye. Modern low-cost tracking systems such as based on RGB-D cameras (e.g., Kinect) come with dynamic errors. Consequently, SPAAM cannot yield the required accuracy; theoretically, dynamic errors require a dynamic calibration. The objective of this research is to study the improvement a dynamic error calibration can yield regarding alignment and registration accuracy. To improve the visual experience for a user, a random forest method will be adopted for this purpose. The hypothesis is that the random forest can dynamically select the best SPAAM calibration matrix with respect to the relative position of the user and a physical object. Experimental results demonstrate improvement by a factor of four; thus, indicate that random forest is an appropriate method to mitigate object misalignment due to dynamic tracking errors

Design Decisions Under Risk and Uncertainty

In the contemporary world of engineering, engineers strive towards designing reliable and robust artifacts while considering and attempting to control manufacturing costs. In due course they have to deal with some sort of uncertainty. Many aspects of the design are the result of properties that are defined within some tolerances, of measurements that are appropriate, and of circumstances and environmental conditions that are out of their control. This uncertainty was typically handled by using factors of safety, and resulted in designs that may have been overly conservative. Therefore, understanding and handling the uncertainties is critical in improving the design, controlling costs and optimizing the product. Since the engineers are typically trained to approach problems systematically, a stepwise procedure which handles uncertainties efficiently should be of significant benefit. This thesis revises the literature, defines some terms, then describes such a stepwise procedure, starting from identifying the sources of uncertainty, to classifying them, handling these uncertainties, and finally to decision making under uncertainties and risk. The document elucidates the methodology introduced by Departments of Mathematical Science and Mechanical Engineering, which considers the after effects of violation of a constraint as a criterion along with the reliability percentage of a design. The approach distinguishes between aleatory and epistemic uncertainties, those that can be assumed to have a certain distribution and those that can only be assumed to be within some bounds. It also attempts to deal with the computational cost issue by approximating the risk surface as a function of the epistemic uncertain variables. The validity of this hypothesis, for this particular problem, is tested by approximating risk surfaces using various numbers of scenarios

Registration (Management) System for an Academic Conference

In every college or university, people will conduct different academic conferences so that students will know what is going on in the world related to the latest technological updates. The conference information should be distributed globally to reach a larger number of people. For many people, physical communication is insufficient, and it won\u27t help people clear their doubts. We propose an online registration management system for the conduct of academic conferences in any college or university to overcome all of the limitations of a physical system in conducting the conference. This new web application will reach every nook and cranny of the globe. People can view the information, they can register with this application, can communicate with the conference people, can get suggestions or recommendations from experts in the same field, etc. To achieve these things, the user needs to sign up with the application, which he should be logged into for doing the different operations in the application. If any of the users want to change their personal information, they will be given the edit option, and they can search for people who are experts in the related field. If needed, they can communicate with them by using this application. Based on the information provided by the user, experts will recommend the related research field so that he or she can opt for it. To create the above application, we will use.Net to create the GUI and implement the application\u27s various operations. We will be using HTML, CSS, BOOTSTRAP, JavaScript, and jQuery in coding, and to store the data, we will be using SQL Server management studio. The framework we are going to use isASP.Net Framework 4.5. According to the schedule, the project will be completed by December 10, 2022

Purification and Analysis of Folate-Dye Conjugate

Folate receptor has achieved great importance for use in targeted drug delivery and in vitro and in vivo diagnostic assays. Folate receptor (FR) is over expressed on several cancer cell types and activated macrophages, but exists in relatively low abundance on the surface of non-cancerous tissue and non-inflammatory cells. This unique attribute is the hallmark of folate – targeted methodologies allowing the diagnostic agent and/or drug to be ferried to the specific disease sites while preventing “off target” effects in normal tissues. Although several folate-based dyes have been reported, simple and detailed synthetic and purification methods for these conjugates have not been reported. Our objective is to develop a new folate-based dye and the corresponding HPLC methods for the purification and analysis of this conjugate. Folate- DylightTM 800 was successfully synthesized by very simple, inexpensive and safe method. The whole synthesis method can be performed in small laboratories with minimum resources and small quantity of reagents required. The synthesis of Folate-DylightTM 800 conjugate was successfully purified by HPLC. The purified Folate-DylightTM 800 conjugate was evaluated by microplate reader, UV-Vis and HPLC

Complex Interactions between Multiple Goal Operations in Agent Goal Management

A significant issue in cognitive systems research is to make an agent formulate and manage its own goals. Some cognitive scientists have implemented several goal operations to support this issue, but no one has implemented more than a couple of goal operations within a single agent. One of the reasons for this limitation is the lack of knowledge about how various goals operations interact with one another. This thesis addresses this knowledge gap by implementing multiple-goal operations, including goal formulation, goal change, goal selection, and designing an algorithm to manage any positive or negative interaction between them. These are integrated with a cognitive architecture called MIDCA and applied in five different test domains. We will compare and contrast the architecture\u27s performance with intelligent interaction management with a randomized linearization of goal operations