38 research outputs found

    Applying Bootstrap Robust Regression Method on Data with Outliers

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    Identification and assessment of outliers have a key role in Ordinary Least Squares (OLS) regression analysis. This paper presents a robust two-stage procedure to identify outlying observations in regression analysis. The exploratory stage identifies leverage points and vertical outliers through a robust distance estimator based on Minimum Covariance Determinant (MCD). After deletion of these points, the confirmatory stage carries out an OLS analysis on the remaining subset of data and investigates the effect of adding back in the previously deleted observations. Cut-off points pertinent to different diagnostics are generated by bootstrapping and the cases are definitely labeled as good-leverage, bad leverage, vertical outliers and typical cases. This procedure is applied to four examples taken from the literature and it is effective in rightly pinpointing outlying observations, even in the presence of substantial masking. This procedure is able to identify and correctly classify vertical outliers, good and bad leverage points, through the use of jackknife-after-bootstrap robust cut-off points. Moreover its two stage structure makes it interactive and this enables the user to reach a deeper understanding of the dataset main features than resorting to an automatic procedure

    Aeroprofili za male Rejnoldsove brojeve.

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    In this thesis, the flow around airfoils at low Reynolds numbers has been modeled. The model utilizes inviscid-viscous interaction method. The inviscid-viscous interaction method supplemented by an adequate laminar separation bubble modeling has been proven to be efficient design tool when numerical optimization, by systematic shape modification, is anticipated...У овој тези је моделирано струјање око аеропрофила са ниским Рејнолдсовим бројем. Вискозно невискозна интеракција комбинована са моделирањем ламинарног мехура је ефикасан метод за конструисање нових аеропрофила систематским модификовањем облика аеропрофила. Невискозно решење је засновано на конформном пресликавању. Вискозна формулација је заснована на решавању интегралних једначина за количину кретања и енергије. Када нема одцепљења струјања примењен је Еплеров модел за предвиђање транзиције из ламинарног у турбулентно струјање. Ламинарни мехур, који узрокује отцепљење је моделиран из три сегмента: ламинарни део, турбулентни део и област прилепљења струјања. Овиме је омогућено одређивање доприноса укупном отпору аеропрофила, такође је омогућено и праћење карактеристика граничног слоја..

    A Surface Plasmon Resonance Bio-Sensor based on Dual Core D-Shaped Photonic Crystal Fibre Embedded with Silver Nanowires for Multi-Sensing

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    K. Senthilnathan and K. Nakkeeran acknowledge the ASEM-DUO for support in the form of an International Joint Project Grant (2020 DUO-India-Scotland Professor Fellowship Award).Peer reviewedPostprin

    Design and Analysis of Surface-Plasmon-Resonance-Based Photonic Quasi-Crystal Fiber Biosensor for High-Refractive-Index Liquid Analytes

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    The work of S. Chu was supported by Elphinestone Scholarship and Thomas and Margaret Roddan Trust Bursary.Peer reviewedPostprin

    Generation of Few-Cycle Laser Pulses Using A Photonic Quasi-crystal Fiber

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    KSN wishes to thank CSIR [No: 03(1264)/12/EMR-11] for the financial support through the project.Postprin

    Neuroprotective activities of Boophone haemanthoides (amaryllidaceae) extract and its chemical constituents

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    Parkinson’s disease (PD) is a neurodegenerative condition that progresses as age increases, and some of its major symptoms include tremor and postural and movement-related difficulties. To date, the treatment of PD remains a challenge because available drugs only treat the symptoms of the disease or possess serious side effects. In light of this, new treatment options are needed; hence, this study investigates the neuroprotective effects of an organic Boophone haemanthoides extract (BHE) and its bioactive compounds using an in vitro model of PD involving the toxin 1-methyl-4-phenylpyridinium (MPP+) and SH-SY5Y neuroblastoma cells

    Dietary Crocin is Protective in Pancreatic Cancer while Reducing Radiation-Induced Hepatic Oxidative Damage.

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    Pancreatic cancer is one of the fatal causes of global cancer-related deaths. Although surgery and chemotherapy are standard treatment options, post-treatment outcomes often end in a poor prognosis. In the present study, we investigated anti-pancreatic cancer and amelioration of radiation-induced oxidative damage by crocin. Crocin is a carotenoid isolated from the dietary herb saffron, a prospect for novel leads as an anti-cancer agent. Crocin significantly reduced cell viability of BXPC3 and Capan-2 by triggering caspase signaling via the downregulation of Bcl-2. It modulated the expression of cell cycle signaling proteins P53, P21, P27, CDK2, c-MYC, Cyt-c and P38. Concomitantly, crocin treatment-induced apoptosis by inducing the release of cytochrome c from mitochondria to cytosol. Microarray analysis of the expression signature of genes induced by crocin showed a substantial number of genes involved in cell signaling pathways and checkpoints (723) are significantly affected by crocin. In mice bearing pancreatic tumors, crocin significantly reduced tumor burden without a change in body weight. Additionally, it showed significant protection against radiation-induced hepatic oxidative damage, reduced the levels of hepatic toxicity and preserved liver morphology. These findings indicate that crocin has a potential role in the treatment, prevention and management of pancreatic cancer

    Dietary Crocin is Protective in Pancreatic Cancer while Reducing Radiation-Induced Hepatic Oxidative Damage

    Get PDF
    Pancreatic cancer is one of the fatal causes of global cancer-related deaths. Although surgery and chemotherapy are standard treatment options, post-treatment outcomes often end in a poor prognosis. In the present study, we investigated anti-pancreatic cancer and amelioration of radiation-induced oxidative damage by crocin. Crocin is a carotenoid isolated from the dietary herb saffron, a prospect for novel leads as an anti-cancer agent. Crocin significantly reduced cell viability of BXPC3 and Capan-2 by triggering caspase signaling via the downregulation of Bcl-2. It modulated the expression of cell cycle signaling proteins P53, P21, P27, CDK2, c-MYC, Cyt-c and P38. Concomitantly, crocin treatment-induced apoptosis by inducing the release of cytochrome c from mitochondria to cytosol. Microarray analysis of the expression signature of genes induced by crocin showed a substantial number of genes involved in cell signaling pathways and checkpoints (723) are significantly affected by crocin. In mice bearing pancreatic tumors, crocin significantly reduced tumor burden without a change in body weight. Additionally, it showed significant protection against radiation-induced hepatic oxidative damage, reduced the levels of hepatic toxicity and preserved liver morphology. These findings indicate that crocin has a potential role in the treatment, prevention and management of pancreatic cancer

    Albumin Nano-Encapsulation of Piceatannol Enhances Its Anticancer Potential in Colon Cancer Via Downregulation of Nuclear p65 and HIF-1 alpha

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    Piceatannol (PIC) is known to have anticancer activity, which has been attributed to its ability to block the proliferation of cancer cells via suppression of the NF-kB signaling pathway. However, its effect on hypoxia-inducible factor (HIF) is not well known in cancer. In this study, PIC was loaded into bovine serum albumin (BSA) by desolvation method as PIC-BSA nanoparticles (NPs). These PIC-BSA nanoparticles were assessed for in vitro cytotoxicity, migration, invasion, and colony formation studies and levels of p65 and HIF-1α. Our results indicate that PIC-BSA NPs were more effective in downregulating the expression of nuclear p65 and HIF-1α in colon cancer cells as compared to free PIC. We also observed a significant reduction in inflammation induced by chemical colitis in mice by PIC-BSA NPs. Furthermore, a significant reduction in tumor size and number of colon tumors was also observed in the murine model of colitis-associated colorectal cancer, when treated with PIC-BSA NPs as compared to free PIC. The overall results indicate that PIC, when formulated as PIC-BSA NPs, enhances its therpautice potential. Our work could prompt further research in using natural anticancer agents as nanoparticels with possiable human clinical trails. This could lead to the development of a new line of safe and effective therapeutics for cancer patients
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