Reduction of Oxidative Stress and Storage Lesions (RCSL) in Red Blood Cells: Analysis of Ascorbic Acid (AA), N-Acetylcysteine amide (AD4), and Serotonin (5-HT)

Oxidative stress is a common occurrence in red blood cell (RBC) storage in blood banks throughout the world. Typically RBC units stored under routine standard protocol (stored in SAGM-CPD additive solution) can only be kept up to forty-two days for transfusion usage before being discarded. I am studying the effects of Ascorbic Acid (AA), N-acetylcysteine amide (AD4), and Serotonin or 5-hydroxytryptamine (5- HT) as additives in blood bank storage to find out if these additives can reduce storageinduced oxidative stress on red blood cells (RBCs), as well as to understand how potential blood storage additives can affect the shelf life of blood and post-transfusion recovery in patients. I conducted a literature review by studying various journal articles that examined metabolism to proteomics and the synergy of the different additives. These various additives significantly alleviated a range of signs of oxidative stress on RBCs including but not limited to replenishing glutathione (GSH), decreasing percent hemolysis, inhibiting the phospholipid rearrangement, and encouraging ATP production. By reducing these symptoms of oxidative stress, RBCs are able to last longer without any significant changes biochemically, and decrease the chances of post-transfusion complications such as Graft vs Host Disease (GVHD). The new additive solution could potentially increase the patient’s post-transfusion recovery rates as well as increase the shelf life of RBC storage units past the standard forty-two days

The Extension of RBC Longevity and Functionality in the Prevention of Graft Versus Host Disease

Given today’s current scientific method of preservation, red blood cells (RBCs) donated or drawn from live humans have a storage life of approximately 42 days, after which the blood will be discarded due to of degradation of the RBCs. The mechanism that drives said degradation is known as oxidative stress, in which the cells’ inability to balance out the creation and excretion of free radicals causes a conformational change in the shape and efficacy of RBCs. In order to counteract the oxidative actions upon the cells, it has been thought that the addition of reducing agents, specifically ascorbic acid, the reduced form of Vitamin C, to the matrix in which the cells are stored can push back the adverse effects of oxidation, allowing the cells to be stored for at least 56 days. The method by which we quantify the efficacy of the said ascorbic acid treatment involves the measurement of blood redox potential using Nanoporous Gold Electrodes (NPGs). By using nanoporous electrodes in contrast to the more conventional planar electrodes, we can minimize the effects of biofouling on the electrochemical response, giving us more reproducible and consistent results. Through Open Circuit Potential (OCP) measurements, we have measured the redox potential of packed RBCs in both large volumes (milliliters) and in single drops (sub-microliters) over a 56-day period. The general statistical trend of the results of the OCPs over the past few months seems to suggest that the ascorbic acid treatment does indeed help stabilize the redox potential of RBCs.https://scholarscompass.vcu.edu/uresposters/1260/thumbnail.jp

Improving Entity Retrieval on Structured Data

The increasing amount of data on the Web, in particular of Linked Data, has led to a diverse landscape of datasets, which make entity retrieval a challenging task. Explicit cross-dataset links, for instance to indicate co-references or related entities can significantly improve entity retrieval. However, only a small fraction of entities are interlinked through explicit statements. In this paper, we propose a two-fold entity retrieval approach. In a first, offline preprocessing step, we cluster entities based on the \emph{x--means} and \emph{spectral} clustering algorithms. In the second step, we propose an optimized retrieval model which takes advantage of our precomputed clusters. For a given set of entities retrieved by the BM25F retrieval approach and a given user query, we further expand the result set with relevant entities by considering features of the queries, entities and the precomputed clusters. Finally, we re-rank the expanded result set with respect to the relevance to the query. We perform a thorough experimental evaluation on the Billions Triple Challenge (BTC12) dataset. The proposed approach shows significant improvements compared to the baseline and state of the art approaches

Reduction of Oxidative Stress and Storage Lesions (RCSL) in Red Blood Cells - Analysis of Ascorbic Acid (AA), N-Acetylcysteine amide (AD4), and Serotonin (5-HT)

Oxidative stress is a common occurrence in red blood cell (RBC) storage in blood banks throughout the world. Typically RBC units stored under routine standard protocol (stored in SAGM-CPD additive solution) can only be kept up to 42 days for transfusion usage before being discarded. I am studying the effects of Ascorbic Acid (AA), N-acetylcysteine amide (AD4), and Serotonin (5-HT) as additives in blood bank storage because I want to find out if these additives can reduce storage-induced oxidative stress on red blood cells (RBCs), in order to help my reader understand how potential blood storage additives can affect the shelf life of blood and post-transfusion recovery in patients. I conducted literature review by studying various journal articles that looked from metabolism to proteomics and the synergy of the different additives. These various additives significantly alleviated a range of signs of oxidative stress on RBCs including but not limited to replenishing GSH, decreasing percent hemolysis and lysis, inhibiting the phospholipid rearrangement, and encouraging ATP production. By reducing these symptoms of oxidative stress, RBCs are able to last longer without any significant changes biochemically, and decrease the chances of post-transfusion complications such as Graft vs Host disease (GVHD). The new additive solution could potentially increase the patient’s outage post-transfusion recovery rates as well as increase the shelf life of RBC storage units past the standard 42 days. Future research should be examined at other additives such as DHA, which RBCs actual transporters in the membrane.https://scholarscompass.vcu.edu/uresposters/1220/thumbnail.jp

Development of a process simulator using object oriented programming: Information modeling and program structure

Object Oriented Programming Languages (OOPL) offer the flexibility of language extension to the specific application of interest. The development effort required for process simulators can be greatly reduced if we extend OOPL with process simulator specific objects and use them for simulation. Design of objects is the most important aspect of development in using OOPL. But OOPL do not provide a methodology to aid in object design. The objects to be designed should reflect the nature of the application at hand.;The objective of this work is to develop an object oriented process simulator to illustrate the benefit of using OOPL in process simulation. An object design criteria is established, an analysis of the object model is performed, and a steady state process simulator using sequential and simultaneous approaches is developed using C++ as the underlying implementation language.;It is found that the object model has to be extended with operational behavior to effectively represent the process simulation information, the development effort is greatly reduced by using the object oriented approach for the process simulator, OOPL can act as common platforms for integrating process engineering activities, and C++ can be effectively used as an implementation language for object oriented process simulation.;Further work is necessary to extend the simulator with dynamic simulation capabilities and to make the simulator interactive and user friendly by developing a graphic interface

It's getting crowded! : improving the effectiveness of microtask crowdsourcing

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A Study on Reduction of Harmonic Distortion caused by AC Arc Furnaces

In AC arc furnaces, arc ignition is stabilized by inductors which are connected across its supply lines. They cause power factor degradation in the system. When furnaces are modelled as linear RL load, the arc nonlinearity reduces the impact of this degradation to a significant extent. Furnace Power factor is improved by the DC voltage on the arc. In this research study, power factor of AC furnaces is estimated on the assumption that DC voltage on the arc is constant and furnace operates in steady state. Primary objective of this research was to determine the power factor of the furnace in steady state. However, other states of operation such as bidirectional arc and unidirectional arc ignition were also taken into consideration while computing the power factor of the furnace. Secondary objective of this research was to understand the effects of harmonics on arc furnace and design filter parameters to mitigate the impact of harmonics caused by the transient operation of the furnaces. Random extinction and ignition of individual arc furnaces help reduce current distortion of ultra-high-power ac arc furnaces using resonant harmonic filters. This operation can be conducted in condition of fast varying parameters of the furnace. On the other hand, this resonant harmonic filter can be built practically only as a constant-parameters device. Filters built on fixed parameters cannot be well coordinated to the furnace. This discrepancy can cause a decline in the filter’s efficacy of harmonics reduction. A reference model using MATLAB was developed to simulate different conditions on the circuit. Also, use of different resonant filters to reduce these harmonics was performed to find the most efficient filter that will increase the efficacy of this process. This efficiency was investigated, specifically, in a melting mode of an arc furnace operation. A reference arc furnace was used in this study which enabled to draw some qualitative and quantitative conclusions on possibilities of current harmonic reduction at a supply of ultra-high-power furnaces by resonant harmonic filters

Modified Selection Mechanisms Designed to Help Evolution Strategies Cope with Noisy Response Surfaces

With the rise in the application of evolution strategies for simulation optimization, a better understanding of how these algorithms are affected by the stochastic output produced by simulation models is needed. At very high levels of stochastic variance in the output, evolution strategies in their standard form experience difficulty locating the optimum. The degradation of the performance of evolution strategies in the presence of very high levels of variation can be attributed to the decrease in the proportion of correctly selected solutions as parents from which offspring solutions are generated. The proportion of solutions correctly selected as parents can be increased by conducting additional replications for each solution. However, experimental evaluation suggests that a very high proportion of correctly selected solutions as parents is not required. A proportion of correctly selected solutions of around 0.75 seems sufficient for evolution strategies to perform adequately. Integrating statistical techniques into the algorithm?s selection process does help evolution strategies cope with high levels of noise. There are four categories of techniques: statistical ranking and selection techniques, multiple comparison procedures, clustering techniques, and other techniques. Experimental comparison of indifference zone selection procedure by Dudewicz and Dalal (1975), sequential procedure by Kim and Nelson (2001), Tukey?s Procedure, clustering procedure by Calsinki and Corsten (1985), and Scheffe?s procedure (1985) under similar conditions suggests that the sequential ranking and selection procedure by Kim and Nelson (2001) helps evolution strategies cope with noise using the smallest number of replications. However, all of the techniques required a rather large number of replications, which suggests that better methods are needed. Experimental results also indicate that a statistical procedure is especially required during the later generations when solutions are spaced closely together in the search space (response surface)

Impact of social media in sports marketing

JEL: M1 - Business Administration; M31 – Marketing; M37 - AdvertisingThe purpose of this research is to evaluate the impact of social media in the field of sports marketing. This is carried out through an in-depth analysis on sports marketing and the rising popularity of social media marketing for sports brands in the world. One such brand is Nike, Inc. This company has shifted its focus to digital marketing. As social media marketing started to explode, the traditional marketing methods such as print, radio and television have begun to slowly fade off into the sunset. The research revolves around the evolution of marketing from traditional to digital techniques over the years. After a significant literature review, a questionnaire regarding the viewing and engagement habits of consumers in Portugal regarding the advertisements of sports brands on traditional and social media was distributed on the internet and 505 responses were collected from people living in Portugal. The results of the questionnaires and the findings obtained lean towards the conclusion that traditional media still holds good value in the market place; at least in Portugal. Social media marketing can be an effective extension of traditional marketing for sports brands. This study demonstrates that sports brands do not need to eliminate traditional marketing methods altogether but must use social media as a supporting factor to their traditional media marketing techniques.O objetivo da presente pesquisa é avaliar o impacto dos media no campo do marketing desportivo. Este trabalho foi concebido através de uma profunda análise do marketing desportivo e da crescente popularidade do marketing dentro dos meios de comunicação para marcas desportivas. Uma dessas marcas é a Nike, Inc.,que recentemente mudou o seu foco para o marketing digital. Com a popularização do marketing nos media, os meios tradicionais, como a imprensa escrita, rádio e televisão, começaram a cair em desuso. Esta pesquisa aborda a evolução do marketing desde os meios tradicionais às técnicas digitais e a sua utilização no sector do desporto ao longo dos anos. Após uma vasta revisão de literatura e uma pesquisa aprofundada sobre o tema em questão, foi preparado um questionário, seguidamente distribuído através da internet. Foram obtidas 505 respostas no território português, com o objetivo de investigar o envolvimento dos participantes e dos seus hábitos com campanhas promocionais e conteúdos de marcas desportivas em meios de comunicação tradicional e social. A conclusão alcançada através da análise dos resultados dos questionários é de que os media tradicionais ainda têm uma importância relativa no mercado. As campanhas de marketing dos sociais são uma extensão eficaz dos media tradicionais para as marcas desportivas. Este estudo revela que marcas desportivas não devem excluir totalmente o uso de meios tradicionais de marketing, mas sim utilizá-los como um suporte para as suas técnicas tradicionais de comunicação

Laminated chemical and physical micro-jet actuators based on conductive media

This dissertation presents the development of electrically-powered, lamination-based microactuators for the realization of large arrays of high impulse and short duration micro-jets with potential applications in the field of micro-electro-mechanical systems (MEMS). Microactuators offer unique control opportunities by converting the input electrical or chemical energy stored in a propellant into useful mechanical energy. This small and precise control obtained can potentially be applied towards aerodynamic control and transdermal drug delivery applications. This thesis discusses the development of both chemical and physical microactuators and characterizes their performance with focus towards the feasibility of using them for a specific application. The development of electrically powered microactuators starts by fabricating an array of radially firing microactuators using lamination-based micro fabrication techniques that potentially enable batch fabrication at low cost. The microactuators developed in this thesis consist of three main parts: a micro chamber in which the propellant is stored; two electrode structures through which electrical energy is supplied to the propellant; and a micro nozzle through which the propellant or released gases from the propellant are expanded as a jet. The fabricated actuators are then integrated with MEMS-process-compatible propellants and optimized to produce rapid ignition of the propellant and generate a fluidic jet. This rapid ignition is achieved either by making the propellant itself conductive, thus, passing an electric current directly through the propellant; or by discharging an arc across the propellant by placing it between two closely spaced electrodes. The first concept is demonstrated with chemical microactuators for the application of projectile maneuvering and the second concept is demonstrated with physical microactuators for transdermal drug delivery application. For both the actuators, the propellant integrated microactuators are characterized for performance in terms of impulse delivered, thrust generated and duration of the jet. The experimentally achieved results are validated by comparing with results from theoretical modeling. Finally, the feasibility of using chemical microactuators for maneuvering the path of a 25 mm projectile spinning at 500 Hz is discussed and the feasibility of applying the physical microactuators for increasing skin's permeability to drug analog molecules is studied.Ph.D.Committee Chair: Allen, Mark; Committee Member: Allen, Sue; Committee Member: Glezer, Ari; Committee Member: Koros, Williams; Committee Member: Prausnitz, Mar