124 research outputs found

    Impedance Sensing of Cancer Cells Directly on Sensory Bioscaffolds of Bioceramics Nanofibers

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    Cancer cell research has been growing for decades. In the field of cancer pathology, there is an increasing and long-unmet need to develop a new technology for low-cost, rapid, sensitive, selective, label-free (i.e. direct), simple and reliable screening, diagnosis, and monitoring of live cancer and normal cells in same shape and size from the same anatomic region. For the first time on using an impedance signal, the breast cancer and normal cells have been thus screened, diagnosed and monitored on a smart bioscaffold of entangled nanowires of bioceramics titanate grown directly on the surface of implantable Ti-metal and characterized by SEM, XRD, etc. following a technology patented by Tian-lab. In experiment in the aqueous solution of phosphate buffer saline (PBS), human breast benign (MCF7) and aggressive (MDA-MB231) cancer cells, normal (MCF10A) cells, and colon cancer cells (HCT116) showed characteristic impedance spectrum highly different than that of the blank sensor (i.e. no cells on the bioscaffold surface). For two sets of mixtures each containing the normal and cancer cells over a wide range of mixing ratios, the shift of impedance signals has been linearly correlated with the mixing ratios which supports the biosensor’s selectivity and reliability. After being treated with pure glucose and chemotherapeutic drug (i.e. doxorubicin of DOX) and with one after the other, the breast cancer cells showed different impedance signals corresponding to their difference in glucose metabolisms (i.e. Warburg Effect) and resistances to the Dox, thus-fingerprinting the cells easily. Based on the nanostructure chemistry, impedance equivalent circuitry and cancer cell biology, it’s the different cells surface binding on the nanowires, and different cancer cells metabolic wastes from the different treatments on the nanowires that changed the charge density on the scaffolding nanowire surface and in turn changed the impedance signals. This new method is believed expandable to quantifying and characterizing live cells and even biological tissues of different types in general

    Effects of Graphical Weather Information versus Textual Weather Information on Situation Awareness in Meteorology

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    Prior to a flight, pilots gather meteorological information to assess the weather conditions pertaining to their flight and to make decisions based on it. This information can come in various formats, such as text and graphical weather information. Research has shown that people have varying learning preferences and that most people prefer visual learning to verbal learning (i.e., graphical over text). It is hypothesized that this difference in learning preference can affect the way pilots interpret and apply the information they obtain prior to their flight. The researcher hypothesizes that graphical weather information has a greater, more positive impact on a pilot’s situation awareness in meteorology than textual weather information. For this study, 20 participants were recruited and presented with two sets of weather information and were then asked to fly two different cross-country flights using the weather information provided. While flying, participants were asked SPAM questions to assess their situation awareness in meteorology. The results showed graphical weather information to be better than textual weather information for the participants’ situation awareness in meteorology. Additional correlations showed evidence that people with both a high preference for visual learning and verbal learning can benefit from graphical weather information over textual weather information. Finally, the data collected indicated that the lack of meteorology training could be a factor in the misinterpretation of weather information. The implications for the findings of this study as well as opportunities for future research are discussed

    Does Postponing Minimum Retirement Age Improve Healthy Behaviours Before Retirement? Evidence from Middle-Aged Italian Workers.

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    By increasing the residual working horizon of employed individuals, pension reforms that rise minimum retirement age can affect individual investment in health-promoting behaviors before retirement. Using the expected increase in minimum retirement age induced by a 2004 Italian pension reform and a difference-in-differences research design, we show that middle-aged Italian males affected by the reform reacted to the longer working horizon by increasing regular exercise, with positive consequences for obesity and self-reported satisfaction with health

    Estimating class sizes by adjusting fallible classifier results

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    AbstractIn discriminant analysis, class sizes are usually estimated by the proportion of a random sample which falls into each class. The accuracy of this method is limited by the low practicability of applying the ideal classification rule to large numbers of objects. How this basic estimator may be improved by taking advantage of the relative feasibility of applying the derived classification rule to large numbers of objects is discussed. Two methods are outlined and comparisons between them are made, resulting in a recommendation that one of the methods should be preferred

    Critical Features in the Microstructural Analysis of AISI 316L Produced By Metal Additive Manufacturing

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    Directed energy deposition (DED) process is recognized as an alternative technology to produce the complex-shape AISI 316L components. The critical production step in this technology is the optimization of process parameters that can directly affect the final properties of the components. To optimize the process parameters, the residual defects of specimens produced with different combinations of process parameters are evaluated, and the optimum condition is chosen. Therefore, the residual defects assessment is a vital step in finding the optimum process parameters; therefore, this evaluation should be carried out carefully. One of the main issues in the production of AISI 316L by DED process is oxidation during the process that should be considered besides the other defects such as porosity and cracks. However, the identification between the oxides and porosities is not an easy task, and so this study aims to provide more clear insight into the evaluation of pores and oxides in DED 316L samples. The outcomes of this work show that at the best process parameters suitable for a porosity-free sample, there are some oxides that can be misinterpreted as porosity and consequently deteriorate the mechanical properties of the dense sample
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