171 research outputs found

    Comparison of Hybrid PSO-SA Algorithm and Genetic Algorithm for Classification

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    In this work, we propose and present a Hybrid particle swarm optimization-Simulated annealing algorithm and compare it with a Genetic algorithm for training respectively neural networks of identical architectures. These neural networks were then tested on a classification task. In particle swarm optimization, behavior of a particle is influenced by the experiential knowledge of the particle as well as socially exchanged information. Particle swarm optimization follows a parallel search strategy. In simulated annealing uphill moves are made in the search space in a stochastic fashion in addition to the downhill moves. Simulated annealing therefore has better scope of escaping local minima and reach a global minimum in the search space. Thus simulated annealing gives a selective randomness to the search. Genetic algorithm performs parallel and randomized search. The goal of training the neural network is to minimize the sum of the squares of the error between the target and observed output values for all the training samples and to deliver good test performance on the test inputs. We compared the performance of the neural networks of identical architectures trained by the  Hybrid particle swarm optimization-simulated annealing and Genetic algorithm respectively on a classification task and noted the results obtained. Neural network trained by Hybrid particle swarm optimization-simulated annealing has given better results compared to the neural network trained by the Genetic algorithm in the tests conducted by us. Keywords: Classification, Hybrid particle swarm optimization-Simulated annealing, Simulated Annealing, Genetic algorithm, Neural Network etc

    Water resource analysis of Minjur Block Thiruvallur district in Tamil Nadu using GIS and remotesensing

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    The study attempts to analyses the water resource availability and its condition in Minjur block. It studies about the water level and its quality of the study area, and examine the condition of water resource and its impact on local community. The region is facing problems related to water level and quality due to industrial pollution, Water scarcity in part of the district due to unfavorable hydro geological set up (Minjur Block). The area faces an alarming situation related to ground water and its level of availability. The study attempts to explore the need of water resources for agriculture and industrial of the region. The base map of Minjur block prepared from survey of India Toposheet on 1:250,000 scale. Temporal variation of water quality analysis will be using SPSS software. Rainfall data will be converted to spatially for annual rainfall using GIS Tool. Satellite imagery has been used for land use and land cover using remote sensing

    Optimal Drug Regimen and Combined Drug Therapy and its Efficacy in the Treatment of COVID-19 : An Within-Host Modeling Study

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    The COVID-19 pandemic has resulted in more than 30.35 million infections and 9, 50, 625 deaths in 212 countries over the last few months. Different drug intervention acting at multiple stages of pathogenesis of COVID-19 can substantially reduce the infection induced mortality. The current within-host mathematical modeling studies deals with the optimal drug regimen and the efficacy of combined therapy in treatment of COVID-19. The drugs/interventions considered include Arbidol, Remdesivir, Inteferon (INF) and Lopinavir/Ritonavir. It is concluded that these drug interventions when administered individually or in combination reduce the infected cells and viral load. Four scenarios involving administration of single drug intervention, two drug interventions, three drug interventions and all the four have been discussed. In all these scenarios the optimal drug regimen is proposed based on two methods. In the first method these medical interventions are modeled as control interventions and a corresponding objective function and optimal control problem is formulated. In this setting the optimal drug regimen is proposed. Later using the the comparative effectiveness method the optimal drug regimen is proposed based on basic reproduction number and viral load. The average infected cell count and viral load decreased the most when all the four interventions were applied together. On the other hand the average susceptible cell count decreased the best when Arbidol alone was administered. The basic reproduction number and viral count decreased the best when all the four interventions were applied together reinstating the fact obtained earlier in the optimal control setting. These findings may help physicians with decision making in treatment of life-threatening COVID-19 pneumonia.Comment: 16 pages, 13 figure

    Системный анализ процесса затвердевания литых заготовок разной массы и назначения

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    Выявлены особенности пространственно-временной эволюции температурных полей в процессе затвердевания разных заготовок (слитков и отливок) для повышения их качества.Виявлено особливості просторово-часової еволюції температурних полів в процесі тверднення різних заготовок (зливків та виливків) для підвищення їх якості.It is revealed the peculiarities of distance-time evolution of the temperature fields in solidification process different billets (ingots and casts) for raise them quality

    The antiapoptotic gene survivin is highly expressed in human chondrosarcoma and promotes drug resistance in chondrosarcoma cells in vitro

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    Background Chondrosarcoma is virtually resistant to chemotherapy and radiation therapy. Survivin, the smallest member of the inhibitor of apoptosis protein family, is a critical factor for tumor progression and resistance to conventional therapeutic approaches in a wide range of malignancies. However, the role of survivin in chondrosarcoma has not been well studied. We examined the importance of survivin gene expression in chondrosarcoma and analysed its influences on proliferation, apoptosis and resistance to chemotherapy in vitro. Methods Resected chondrosarcoma specimens from which paraffin-embedded tissues could be extracted were available from 12 patients. In vitro experiments were performed in human chondrosarcoma cell lines SW1353 and Hs819.T. Immunohistochemistry, immunoblot, quantitative PCR, RNA interference, gene-overexpression and analyses of cell proliferation and apoptosis were performed. Results Expression of survivin protein was detected in all chondrosarcoma specimens analyzed, while undetectable in adult human cartilage. RNA interference targeting survivin resulted in a G2/M-arrest of the cell cycle and led to increased rates of apoptosis in chondrosarcoma cells in vitro. Overexpression of survivin resulted in pronounced resistance to doxorubicin treatment. Conclusions These findings indicate that survivin plays a role in the pathogenesis and pronounced chemoresistance of high grade chondrosarcoma. Survivin antagonizing therapeutic strategies may lead to new treatment options in unresectable and metastasized chondrosarcoma

    Natural history of SLC11 genes in vertebrates: tales from the fish world

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    <p>Abstract</p> <p>Background</p> <p>The <it>SLC11A1/Nramp1 </it>and <it>SLC11A2/Nramp2 </it>genes belong to the <it>SLC11/Nramp </it>family of transmembrane divalent metal transporters, with <it>SLC11A1 </it>being associated with resistance to pathogens and <it>SLC11A2 </it>involved in intestinal iron uptake and transferrin-bound iron transport. Both members of the <it>SLC11 </it>gene family have been clearly identified in tetrapods; however <it>SLC11A1 </it>has never been documented in teleost fish and is believed to have been lost in this lineage during early vertebrate evolution. In the present work we characterized the <it>SLC11 </it>genes in teleosts and evaluated if the roles attributed to mammalian <it>SLC11 </it>genes are assured by other fish specific <it>SLC11 </it>gene members.</p> <p>Results</p> <p>Two different <it>SLC11 </it>genes were isolated in the European sea bass (<it>Dicentrarchus. labrax</it>), and named <it>slc11a2-α </it>and <it>slc11a2-β</it>, since both were found to be evolutionary closer to tetrapods <it>SLC11A2</it>, through phylogenetic analysis and comparative genomics. Induction of <it>slc11a2-α </it>and <it>slc11a2-β </it>in sea bass, upon iron modulation or exposure to <it>Photobacterium damselae </it>spp. <it>piscicida</it>, was evaluated in <it>in vivo </it>or <it>in vitro </it>experimental models. Overall, <it>slc11a2-α </it>was found to respond only to iron deficiency in the intestine, whereas <it>slc11a2-β </it>was found to respond to iron overload and bacterial infection in several tissues and also in the leukocytes.</p> <p>Conclusions</p> <p>Our data suggests that despite the absence of <it>slc11a1</it>, its functions have been undertaken by one of the <it>slc11a2 </it>duplicated paralogs in teleost fish in a case of synfunctionalization, being involved in both iron metabolism and response to bacterial infection. This study provides, to our knowledge, the first example of this type of sub-functionalization in iron metabolism genes, illustrating how conserving the various functions of the SLC11 gene family is of crucial evolutionary importance.</p
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