247 research outputs found

    The Effects of Cell Clustering on Cell Differentiation in Human Pancreatic Ductal Epithelial Cancer Cells

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    The thesis was funded by the College of Engineering by the Undergraduate Research Scholarship, when the project proposal was approved in April 2011.For diabetes mellitus type I, regular insulin therapy is not enough to completely control the disease. Ineffective control of blood glucose levels can lead to complications in other parts of the body, including kidney failure, neuropathy, cardiovascular disease, blindness, and acute hypoglycemic attacks. Although pancreatic transplants are one possible solution to reduce the effects of diabetes, it is not the best option. The proposed work of this research project is new and innovative with respect to hypothesis and methodology. It follows the goal to identify the role of cell clustering for differentiation of β cells so that the option of pancreatic islet transplantation can be substituted completely. Work by Boretti and Gooch in their paper “Induced Cell Clustering Enhances Islet β Cell Formation from Human Cultures Enriched for Pancreatic Ductal Epithelial Cells” was relevant to this project as it established the importance of clustering for differentiation of precursors cells into β cells. I used this work as a motivation to further research the amount of clustering required for the expression of insulin. My project speculates that the number of cells per cluster is essential for differentiated β cells to form. Further, there also must be a certain number of cells per cluster in order for proper insulin expression to take place. Upon experimentation, the results showed that cluster sizes of at least 4 cells per cluster were successful in expressing insulin as differentiated β cells. Whereas, small cluster sizes with only 1-2 cells per cluster were not able to express insulin. Further an area-to-perimeter analysis showed that ratios greater than 4.5 were common among insulin-expressing large cluster sizes. Although the results are quite preliminary, the investigation of the role that cluster size has on differentiation of β cells has a lot of potential for further research.The Ohio State University, College of Engineering, Undergraduate Research Scholarship (URS)No embarg

    Intelligent Search in eBook Repository

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    Nowadays a lot of systems are available for searching e-books, but the ways to retrieve relevant and meaningful information are difficult. To cope with this problem of retrieving relevant information efficiently we proposed a system, which allows user to search e-books using semantically enriched queries. Our approach not only facilitates users for intelligent e-book search but it also facilitates user in locating their desired information inside the e-book

    FedDefender: Backdoor Attack Defense in Federated Learning

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    Federated Learning (FL) is a privacy-preserving distributed machine learning technique that enables individual clients (e.g., user participants, edge devices, or organizations) to train a model on their local data in a secure environment and then share the trained model with an aggregator to build a global model collaboratively. In this work, we propose FedDefender, a defense mechanism against targeted poisoning attacks in FL by leveraging differential testing. Our proposed method fingerprints the neuron activations of clients' models on the same input and uses differential testing to identify a potentially malicious client containing a backdoor. We evaluate FedDefender using MNIST and FashionMNIST datasets with 20 and 30 clients, and our results demonstrate that FedDefender effectively mitigates such attacks, reducing the attack success rate (ASR) to 10\% without deteriorating the global model performance.Comment: Published in SE4SafeML 2023 (co-located with FSE 2023). See https://dl.acm.org/doi/abs/10.1145/3617574.361785

    FedDebug: Systematic Debugging for Federated Learning Applications

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    In Federated Learning (FL), clients independently train local models and share them with a central aggregator to build a global model. Impermissibility to access clients' data and collaborative training make FL appealing for applications with data-privacy concerns, such as medical imaging. However, these FL characteristics pose unprecedented challenges for debugging. When a global model's performance deteriorates, identifying the responsible rounds and clients is a major pain point. Developers resort to trial-and-error debugging with subsets of clients, hoping to increase the global model's accuracy or let future FL rounds retune the model, which are time-consuming and costly. We design a systematic fault localization framework, FedDebug, that advances the FL debugging on two novel fronts. First, FedDebug enables interactive debugging of realtime collaborative training in FL by leveraging record and replay techniques to construct a simulation that mirrors live FL. FedDebug's breakpoint can help inspect an FL state (round, client, and global model) and move between rounds and clients' models seamlessly, enabling a fine-grained step-by-step inspection. Second, FedDebug automatically identifies the client(s) responsible for lowering the global model's performance without any testing data and labels--both are essential for existing debugging techniques. FedDebug's strengths come from adapting differential testing in conjunction with neuron activations to determine the client(s) deviating from normal behavior. FedDebug achieves 100% accuracy in finding a single faulty client and 90.3% accuracy in finding multiple faulty clients. FedDebug's interactive debugging incurs 1.2% overhead during training, while it localizes a faulty client in only 2.1% of a round's training time.Comment: Published at ICSE 2023. Link https://ieeexplore.ieee.org/document/1017283

    Allelopathic Effect of Methanol and Water Extracts of \u3cem\u3eCamellia sinensis\u3c/em\u3e L. on Seed Germination and Growth of \u3cem\u3eTriticum aestivum\u3c/em\u3e L. and \u3cem\u3eZea mays\u3c/em\u3e L.

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    This study describes the possible effects of tea residues on crop production. To investigate the negative effects of tea on two cereal crops, i.e. wheat and maize, laboratory experiments were conducted during May 2014 and repeated in June 2014 to study the effect of black tea extract on wheat and maize seeds’ germination and growth. The experiment was conducted in petri dishes and laid out in completely randomized designs, replicated thrice. The petri dishes were kept in a growth chamber, with the temperature set at 25°C. 50 g of each dried fresh and used black tea was separately soaked in 500 ml of hot and cold distilled water. The same amount of tea residue was soaked in 500 ml of methanol. Ten seeds of each wheat variety (Siran) and maize variety (Azam) were placed in each petri dish. 10 ml of each extract was applied to each petri dish according to the requirement. A control (distilled water) was used for comparison. Analysis of the data revealed that tea extract significantly suppressed seed germination and the growth of wheat and maize. Methanol extracts, on the other hand, completely inhibited seed germination. The negative effects of tea extracts on seed germination of crops warns that apart from polluting the soil, the crop production could be greatly affected by dumping tea waste in agricultural fields. However, used cautiously, the application of tea extract can be used to suppress the growth of weeds in agriculture

    THE APPLICATION OF EARNED VALUE MANAGEMENT FOR TIME AND COST MONITORING WITHIN THE MALAYSIAN CONSTRUCTION INDUSTRY

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    The management of construction projects are becoming more challenging for civil engineers in the 21st century due to increasingly competitive performance expectations from the project stakeholders. However, among the financial and non-financial performance indicators, time and cost monitoring of construction projects are the critical issues for an effective project management. The traditional approach of project time and cost performance measurement is generally based on direct monitoring in which there is a split-up between them. Both of these parameters are measured and reported in isolation with each other by comparing their planned and actual values. Therefore, the traditional monitoring approach does not truly relate the time versus cost performance of the project. Furthermore, this approach is not so much efficient to provide early warning indicators and forecast future performance trends. As a remedy of these limitations in traditional monitoring practices, Earned Value Management (EVM) methodology integrates the work scope, cost and schedule to enable effective project performance measurement. EVM is based on three data sources and is able to compare the budgeted value of work scheduled (PV) with the Earned Value (EV) of physical work completed and the Actual Cost (AC) of work completed. Hence, performance data achieved by using EVM is an objective measure of actual work performed and can be used for the future performance analysis and forecasting. Due to these advantages, this study has proposed EVM method and extends its knowledge and applications for the Malaysian construction industry. The proposed study is based on a mixed methodology that incorporates both quantitative and qualitative methods and is designed into three phases. The first phase is based on a quantitative survey that aims to obtain a perception, understanding, barriers and enablers of EVM method for the local construction industry. The second and third phases will subsequently employ qualitative data collection and analysis of EVM applications through case studies and semi structured interviews. The questionnaire feedbacks were analyzed by using statistical tools such as frequency analysis, cross-tabulation, average index analysis, spearman’s correlation and Kendall’s coefficient of concordance to establish findings. This survey reveals that although the EVM methodology is recognized by the practitioners of local construction industry, nevertheless it is not very much in use. As 80% of the respondents are not practicing EVM method in their working environment. The survey has identified the “lack of EVM knowledge, expertise and experience” as the most important barriers. The study has found that there is a good degree of agreement among the respondents regarding the potential enablers of EVM method. The analysis of descriptive case studies explores the applications of EVM in different project scenarios. The study has also determined from the perspective of construction experts that EVM methodology would facilitate the clients and contractors in terms of integrated cost, schedule, and technical performance measures. The overall findings of this study support the application of EVM as a standardized project control method for the Malaysian construction industry

    Reflection of Regulatory Announcement in Equity Market: Fresh Insight from Oil & Gas Sector of Pakistan

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    This study is based on the problem that how regulations made by oil and gas regulatory authority influences the companies in oil and gas sector of Pakistan. We identify 13 regulatory changes in oil and sector of Pakistan which broadly includes the announcement related to the formulation, functions and responsibilities of oil and gas authority, deregulation and changes in the prices of oil and gas products, interference of apex court into the oil and gas sector and privatization of oil refineries in emerging market of Pakistan. Well-liked event study methodology is used to uncover the impact of regulation announcement on equity prices in Pakistan. Beside this, we also capture the effect of regulation announcement on the firm performance by introducing the dummy variable in ordinary least framework. In line with the financial and econometric theory criteria, we use the sales growth, leverage, liquidity and tangibility as control variables. Study reveal that regulatory announcements have statistically significant aggregate effect on the oil and gas sector of Pakistan stock exchange. We recommend to the policy makers, managers and regulators that the stock prices of oil and gas companies are more sensitive toward the regulatory announcements related to interference of Supreme Court and regulations concerning to the formulation, functions and responsibilities of oil and gas regulatory authority in Pakistan

    Individual, structural, and institutional factors are involved to boost the informal entrepreneurial activities. A literature review of developing nations

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    The study reviews the literature of determinants of informal entrepreneurship in developed and developing nations and finds the major causes that fabricate the informal culture, which is individuallevel, structural level and institutional level. The objective of this paper is to explore the important determinants of informal entrepreneurship in developing nations. Few factors have commonalities with other factors that have been discussed in the literature. Few determinants have explored as additional determinants that have not been discussed by Colin’s Model that was based on developed nations. This study has explored these factors as some additional factors in Colin’s model. Additional factors are entrepreneurial spawning, availability of resources, family tradition, and support of family members. No single factor is yet able to detect the difficulties of this sector, the nature of the informal entrepreneurship is always clarified by a “cocktail” of factors

    Afghan Migration and its Impacts on Community of Afghanistan

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    The history of migration is by far one of the very harshest and difficult topics in this new era of modernization. This article is going to define a particular part of the migration history and its aspects, which will be focusing mainly on a far-distant and barely remembered land called Afghanistan. Here we take you to the times of despair and hopelessness of a nation which has had war over war, conflict over conflict and which has seen empires come and go for over 3 centuries. This article talks about the poor condition of those people who had no other option but to leave their lands, harvests and sometimes even families because they were harmed by the war. What happens when one flees their country? Why would someone be this desperate? How does one deal with this inconvenience? What are the impacts of this immigration on a country? Do they ever return? The role of the neighboring countries has always been a very important issue in this topic like these. They have since been receiving our desperate and turmoil people who were in need of a shelter and asking for help for their survival’s sake. It will be unprofessional to just talk about their help and not their benefits from this vast immigration. They have also availed from our immigration. Pakistan and Iran have had very faithful and scared people working for them for a very less expensive wages which in other case would never have been the same
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