Big data refers to datasets that we cannot manage with standard tools and within which lie valuable information previously hidden. New data mining techniques are needed to deal with the increasing size of such data, their complex structure as well as their veracity which is on covering questions of data imperfection and uncertainty. Even though big data veracity is often overlooked, it is very challenging and important for an accurate and reliable mining and knowledge discovery. This paper proposes MapReduce-based belief decision trees for big data as classifiers of uncertain large-scale datasets. The proposed averaging and conjunctive classification approaches are experimented for intrusion detection on KDD’99 massive intrusion dataset. Several granularity attacks’ levels have been considered depending on whether dealing with whole kind of attacks, or grouping them in categories or focusing on distinguishing normal and abnormal connections. 相似文献
In this brief note, we present an approach that combines the three classical techniques in structural optimization, i.e. the
boundary variation and the topological and the homogenization methods. As a first test of this method, we apply it to the
compliance opti-mization in . 相似文献
We measured the ultrasonic velocity, U, density, ρ, and viscosity, η in Isobutyric acid - water binary liquid mixtures over the entire composition range at temperatures ranging from 300.15 to 313.15 K under atmospheric pressure. The experimental data values were analyzed to determine, various acoustical parameters: adiabatic compressibility, β, acoustic impedance, Z, free length, Lf, free volume, Vf, molar volume, Vm, relaxation time, τ, absorption coefficient, α/f2, internal pressure, πi, Gibb’s free energy, ΔG, cohesive energy, CE, Wada’s constant, W, Rao’s constant, Rm and relative association, RA. The variation of these parameters versus the mixture composition was explained on the basis of the intermolecular interactions between the components of the mixture. 相似文献
Liquid chromatographic method was presented for the determination of flavoxate hydrochloride (FX) and its hydrolysis product. The method was based on high-performance liquid chromatographic (HPLC) separation of FX from its hydrolysis product on CN column using a mobile phase consisting of acetonitrile-12 mM ammonium acetate (45:55, vol/vol, pH 4.0) with UV detection at 220 nm and flow rate of 1.5 mL min(-1). The proposed HPLC method for the determination of FX was utilized to investigate the kinetics of acidic hydrolytic process at different temperatures and to calculate its activation energy. In addition, the proposed HPLC method was used for pH-rate profile study of hydrolysis of FX in Britton-Robinson buffer solutions. The 3-methylflavone-8-carboxylic acid ethyl ester, as impurity of flavoxate hydrochloride, can be separated by the proposed HPLC method. 相似文献
The molecular basis for the voltage and pH dependence of the Escherichia coli OmpF porin activity remains unknown. The L3 loop was previously shown not be involved in voltage dependence. Here we used seven OmpF mutants where single extracellular loops, except L3, were deleted one at a time. The proteins are expressed at levels comparable to wild-type and purified as trimers. Wild-type and mutant proteins were inserted into planar lipid bilayers for electrophysiological measurement of their activity. Current-voltage relationships show the typical porin channel closure at voltages greater than the critical voltage. Measurements of critical voltages for the seven deletion mutants showed no significant differences relative to wild-type, hence eliminating the role of single loops in voltage sensitivity. However, deletions of loops L1, L7 or L8 affected the tendency of channels to close at acidic pH. Wild-type channels close more readily at acidic pH and their open probability is decreased by approximately 60% at pH 4.0 relative to pH 7.0. For mutants lacking loop L1, L7 or L8, the channel open probability was found not to be significantly different at pH 4.0 than at pH 7.0. The other deletion mutants retained a pH sensitivity similar to the wild-type channel. Possible mechanistic scenarios for the voltage- and pH dependence of E.coli OmpF porin are discussed based on these results. 相似文献
The TopoTomo bending magnet beamline at the ANKA synchrotron facility in Karlsruhe (Germany) operates in the hard X-ray regime (above 6 keV). Recently, an X-ray micro-imaging station has been installed at TopoTomo. For typical imaging applications, a filtered white beam or from 2009 on a double-multilayer monochromator is used. In order to optimize the field of view and the resolution of the available indirect pixel detectors, different optical systems have been installed, adapted, respectively, to a large field of view (macroscope) and to high spatial resolution (microscope). They can be combined with different camera systems, ranging from 14-bit dynamic range CCDs to fast CMOS cameras. The spatial resolution can be brought substantially beyond the micrometer limit by using a Bragg magnifier. Due to the moderate flux of the beamline compared to insertion-device beamlines on third generation light sources, special emphasis has been put on the efficiency of the detectors via a dedicated scintillator concept. The layout of the beamline optics makes optimal use of the coherence properties. Thus, absorption contrast, phase-contrast and analyzer-based imaging can be applied. Additionally, white beam synchrotron topography is performed, using digital indirect X-ray pixel detectors as well as X-ray film. 相似文献
The present work describes the implementation of the multiple scattering formalism for charged particle transport based on the Goudsmit–Saunderson angular distribution and satisfying the Lewis spatial displacement theories. Furthermore, the most realistic total cross sections and transport cross sections for single elastic scattering of electrons and positrons by neutral atoms were carried out using the ELSEPA code. The extended model has been incorporated in the Geant4 Monte Carlo code system (currently used in many fields of application for transport of particles and covering a large range of energies from 0.1 keV to 100 TeV). Additionally, techniques are developed that allow the distributions to be scaled to account for energy loss. This new representation allows on-the-fly sampling of Goudsmit–Saunderson angular distributions in a screened Rutherford approximation suitable for Class II condensed history Monte Carlo codes. The reliability of the model is demonstrated through a comparison of simulation results with experimental data. Good agreement is found for electrons with kinetic energies down to a few keV. 相似文献
The Hedgehog (HH) signaling pathway plays an essential role in mouse lung development. We hypothesize that the HH pathway is necessary for branching during human lung development and is impaired in pulmonary hypoplasia. Single-cell, bulk RNA-sequencing data, and human fetal lung tissues were analyzed to determine the spatiotemporal localization of HH pathway actors. Distal human lung segments were cultured in an air-liquid interface and treated with an SHH inhibitor (5E1) to determine the effect of HH inhibition on human lung branching, epithelial-mesenchymal markers, and associated signaling pathways in vitro. Our results showed an early and regulated expression of HH pathway components during human lung development. Inhibiting HH signaling caused a reduction in branching during development and dysregulated epithelial (SOX2, SOX9) and mesenchymal (ACTA2) progenitor markers. FGF and Wnt pathways were also disrupted upon HH inhibition. Finally, we demonstrated that HH signaling elements were downregulated in lung tissues of patients with a congenital diaphragmatic hernia (CDH). In this study, we show for the first time that HH signaling inhibition alters important genes and proteins required for proper branching of the human developing lung. Understanding the role of the HH pathway on human lung development could lead to the identification of novel therapeutic targets for childhood pulmonary diseases. 相似文献
Objectives: This study was aimed to develop dual-purpose natamycin (NAT)-loaded niosomes in ketorolac tromethamine (KT) gels topical ocular drug delivery system to improve the clinical efficacy of natamycin through enhancing its penetration through corneal tissue and reducing inflammation associated with Fungal keratitis (FK).
Significance: Nanosized carrier systems, as niosomes would provide great potential for improving NAT ocular bioavailability.NAT niosomal dispersion formulae were prepared and then incorporated in 0.5%KT gels using different mucoadhesive viscosifying polymers.
Methods: Niosomes were prepared using the reverse-phase evaporation technique. In vitro experimental, and in vivo clinical evaluations for these formulations were done for assessment of their safety and efficacy for treatment of Candida Keratitis in Rabbits. In vitro release study was carried out by the dialysis method. In vivo and histopathological studies were performed on albino rabbits.
Results: NAT niosomes exhibited high entrapment efficiency percentage (E.E%) up to96.43% and particle size diameter ranging from 181.75?±?0.64 to 498.95?±?0.64?nm, with negatively charged zeta potential (ZP). NAT niosomal dispersion exhibited prolonged in vitro drug release (40.96–77.49% over 24h). NAT-loaded niosomes/0.5%KT gel formulae revealed retardation in vitro release, compared to marketed-product (NATACYN®) and NAT-loaded niosomes up to57.32% (F8). In vivo experimental studies showed the superiority for F8 in treatment of candida keratitis and better results on corneal infiltration and hypopyon level. These results were consistent with histopathological examination in comparison with F5 and combined marketed products (NATACYN® and Ketoroline®).
Conclusions: This study showed that F8 has the best results from all pharmaceutical in vitro evaluations and a better cure percent in experimental application and enhancing the prolonged delivery of NAT and penetrating the cornea tissues. 相似文献