994 research outputs found

    A Review of Clustering Algorithms for Clustering Uncertain Data

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    Clustering is an important task in the Data Mining. Clustering on uncertain data is a challenging in both modeling similarity between objects of uncertain data and developing efficient computational method. The most of the previous method for clustering uncertain data extends partitioning clustering methods and Density based clustering methods, which are based on geometrical distance between two objects. Such method cannot handle uncertain objects that are cannot distinguishable by using geometric properties and Distribution regarding to object itself is not considered. Probability distribution is an important characteristic is not considered during measuring similarity between two uncertain objects. The well known technique Kullbak-Leibler divergence used to measures the similarity between two uncertain objects. The goal of this paper is to provide detailed review about clustering uncertain data by using different methods & showing effectiveness of each algorithm

    Estrogen as therapy for breast cancer

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    High-dose estrogen was generally considered the endocrine therapy of choice for postmenopausal women with breast cancer prior to the introduction of tamoxifen. Subsequently, the use of estrogen was largely abandoned. Recent clinical trial data have shown clinically meaningful efficacy for high-dose estrogen even in patients with extensive prior endocrine therapy. Preclinical research has demonstrated that the estrogen dose-response curve for breast cancer cells can be shifted by modification of the estrogen environment. Clinical and laboratory data together provide the basis for developing testable hypotheses of management strategies, with the potential of increasing the value of endocrine therapy in women with breast cancer

    Soil biological properties as influenced by long-term manuring and fertilization under sorghum (Sorghum bicolor) -wheat (Triticum aestivum) sequence in Vertisols

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    The effect of long-term manuring and fertilization on soil biological properties was studied under the long term fertilizer experiment on sorghum [Sorghum bicolor (L.) Moench] -wheat (Triticum aestivum L.) sequence conducted on Vertisols. The treatments comprised 50% RDF, 100% RDF, 150% RDF,100% RDF (-S), 100% RDF + 2.5 kg Zn/ ha to wheat crop only, 100% RD of NP, 100% RD of N, 100% RDF + FYM @ 10 tonnes/ha, 100% RDF + S @ 37.5 kg/ ha, FYM @ 10 tonnes/ha, 75% RDF and control. The assessment of soil biological properties at 40 and 70 days after sowing revealed that, significantly highest CO2 evolution was recorded at 70 DAS of sorghum under 100% RDF + FYM @ 10 tonnes/ ha ( 66.82 mg/ 100 kg). Soil microbial biomass carbon was also influenced significantly with the combined application of NPK+FYM (278.9 mg/ kg). The soil enzyme activity, viz. dehydrogenase (55.01 ”g TPF/g/24 hr), urease (47.9 mg NH4/kg/ 24 hr) and cellulase (52.23 ”g glucose/g/24 hr) were significantly influenced with the application of 100% RDF + FYM @ 10 tonnes/ha. Similarly, the application of 100% RDF + FYM @ 10 tonnes/ha recorded significantly higher grain yield of sorghum

    Application of the Beer–Lambert Model to Attenuation of Photosynthetically Active Radiation in a Shallow, Eutrophic Lake

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    Models of primary production in aquatic systems must include a means to estimate subsurface light. Such models often use the Beer–Lambert law, assuming exponential attenuation of light with depth. It is further assumed that the diffuse attenuation coefficient may be estimated as a summation of scattering/absorbing constituent concentrations multiplied by their respective specific attenuation coefficients. While theoretical deviations from these assumptions have been documented, it is useful to consider the empirical performance of this common approach. Photosynthetically active radiation (PAR) levels and water quality conditions were recorded weekly from six to eight monitoring stations in western Lake Erie between 2012 and 2016. Exponential PAR extinction models yielded a mean attenuation coefficient of 1.55 m (interquartile range = 0.74–1.90 m). While more complex light attenuation models are available, analysis of residuals indicated that the simple Beer–Lambert model is adequate for shallow, eutrophic waters similar to western Lake Erie (R2 > 0.9 for 96% of samples). Three groups of water quality variables were predictive of PAR attenuation: total and nonvolatile suspended particles, dissolved organic substances (dissolved organic carbon and chromophoric dissolved organic matter), and organic solids (volatile suspended solids and chlorophyll). Multiple regression models using these variables predicted 3–90% of the variability in PAR attenuation, with a median adjusted R2 = 0.86. Explanatory variables within these groups may substitute for each other while maintaining similar model performance, indicating that various combinations of water quality variables may be useful to predict PAR attenuation, depending on availability within a model framework or monitoring program.Key PointsThe Beer–Lambert law effectively models photosynthetically active radiation in western Lake Erie, despite some systematic deviationsField‐obtained water quality parameters can predict photosynthetically active radiation attenuation with a high degree of confidenceSuspended particle concentration is most predictive of photosynthetically active radiation attenuation in this turbid, eutrophic basinPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/147097/1/wrcr23654_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/147097/2/wrcr23654-sup-0001-2018WR023024-SI.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/147097/3/wrcr23654.pd

    Emergence and divergence of major lineages of shiga-toxin-producing escherichia coli in Australia

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    Shiga-toxin-producing Escherichia coli (STEC) infection is an important global cause of foodborne disease. To date however, genomics-based studies of STEC have been predominately focused upon STEC collected in the Northern Hemisphere. Here, we demonstrate the population structure of 485 STEC isolates in Australia, and show that several clonal groups (CGs) common to Australia were infrequently detected in a representative selection of contemporary STEC genomes from around the globe. Further, phylogenetic analysis demonstrated that lineage II of the global O157:H7 STEC was most prevalent in Australia, and was characterized by a frameshift mutation in flgF, resulting in the H-non-motile phenotype. Strong concordance between in silico and phenotypic serotyping was observed, along with concordance between in silico and conventional detection of stx genes. These data represent the most comprehensive STEC analysis from the Southern Hemisphere, and provide a framework for future national genomics-based surveillance of STEC in Australia.Danielle J. Ingle, Anders Gonçalves da Silva, Mary Valcanis, Susan A. Ballard, Torsten Seemann, Amy V. Jennison, Ivan Bastian, Rolf Wise, Martyn D. Kirk, Benjamin P. Howden, Deborah A. Williamso

    Tracking the ultraviolet-induced photochemistry of thiophenone during and after ultrafast ring opening

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    Photoinduced isomerization reactions lie at the heart of many chemical processes in nature. The mechanisms of such reactions are determined by a delicate interplay of coupled electronic and nuclear dynamics occurring on the femtosecond scale, followed by the slower redistribution of energy into different vibrational degrees of freedom. Here we apply time-resolved photoelectron spectroscopy with a seeded extreme ultraviolet free-electron laser to trace the ultrafast ring opening of gas-phase thiophenone molecules following ultraviolet photoexcitation. When combined with ab initio electronic structure and molecular dynamics calculations of the excited- and ground-state molecules, the results provide insights into both the electronic and nuclear dynamics of this fundamental class of reactions. The initial ring opening and non-adiabatic coupling to the electronic ground state are shown to be driven by ballistic S–C bond extension and to be complete within 350 fs. Theory and experiment also enable visualization of the rich ground-state dynamics that involve the formation of, and interconversion between, ring-opened isomers and the cyclic structure, as well as fragmentation over much longer timescales

    Ethics and ‘fracking’: A review of (the limited) moral thought on shale gas development

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    Whilst claims about the ethicality of shale gas development via hydraulic fracturing (‘fracking’) are commonplace in everyday discourse, little scholarly attention has been afforded explicitly to this aspect of unconventional fossil fuel extraction. The limited research that speaks to ethical considerations largely describes ethical concerns associated with development – extremely few claims in research literature make an ethical case for development. The most common ethical concerns cited in research stem from issues of distributive justice, with procedural justice, the precautionary principle, exposure to involuntary risks, rights-based arguments, and changes in community character and way of life as next most common. Additional research hints implicitly at ethical dilemmas associated with shale gas development, but does not openly identify these issues as having moral implications. Many ethical considerations relate closely to concerns about water quality and the volume/supply of water available for other purposes. The limited scholarship in this area reveals the import of understanding the ways in which ethics permeate thoughts about shale gas development for designing policy that responds to constituent needs and concerns. Even more limited than research on ethical claims in association with shale gas development is well-reasoned scholarship that analyses the extent to which ethical claims about development are well justified and philosophically justifiable. A comprehensive and systematic analysis of the range of ethical claims potentially relevant to shale gas development and their usefulness for informing policy on this topic would contribute greatly to informed decision-making on this controversial issue – something that science alone cannot achieve
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