A big data MapReduce framework for fault diagnosis in cloud-based manufacturing

This research develops a MapReduce framework for automatic pattern recognition based on fault diagnosis by solving data imbalance problem in a cloud-based manufacturing (CBM). Fault diagnosis in a CBM system significantly contributes to reduce the product testing cost and enhances manufacturing quality. One of the major challenges facing the big data analytics in cloud-based manufacturing is handling of datasets, which are highly imbalanced in nature due to poor classification result when machine learning techniques are applied on such datasets. The framework proposed in this research uses a hybrid approach to deal with big dataset for smarter decisions. Furthermore, we compare the performance of radial basis function based Support Vector Machine classifier with standard techniques. Our findings suggest that the most important task in cloud-based manufacturing, is to predict the effect of data errors on quality due to highly imbalance unstructured dataset. The proposed framework is an original contribution to the body of literature, where our proposed MapReduce framework has been used for fault detection by managing data imbalance problem appropriately and relating it to firm’s profit function. The experimental results are validated using a case study of steel plate manufacturing fault diagnosis, with crucial performance matrices such as accuracy, specificity and sensitivity. A comparative study shows that the methods used in the proposed framework outperform the traditional ones

Histological assessment of the impact of <i>S</i>. <i>aureus</i> virulence factors on retinal tissue damage.

<p>Histological analysis was performed on eyes challenged with <i>S</i>. <i>aureus</i> virulence factors as indicated in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0128423#pone.0128423.g002" target="_blank">Fig 2</a> legend. Representative images of eyes of inoculated challenged with <i>S</i>. <i>aureus</i> and α-toxin (0.1μg/eye) showed retinal damage. Original magnifications 20X. VC, Vitreous Chamber; R, Retina; OD, Optic Disk.</p

Expressions of MMPs and S100As in eye challenged with <i>S</i>. <i>aureus</i> and its virulence factors.

<p>Eyes of C57BL/6 mice (4–6 per group) were inoculated intravitreally with live <i>S</i>. <i>aureus</i> (5000 CFU/eye), HKSA (5X10⁵ CFU/eye), LTA (0.1μg/eye), PGN (0.1μg/eye), TSST1 (0.1μg/eye), α-toxin (0.1μg/eye), SPA (0.1μg/eye), and PBS (2μl) for 24h. The mRNA expression of MMP2, MMP9, MMP13, S100A7, and S100A9 was determined by Real-time RT-PCR. Statistical analysis was performed by using one way ANOVA with Dunnett’s multi-comparison test. <i>*p</i> <0.05, <i>**p</i> <0.005.</p

Role of <i>Staphylococcus aureus</i> Virulence Factors in Inducing Inflammation and Vascular Permeability in a Mouse Model of Bacterial Endophthalmitis

<div><p><i>Staphylococcus (S</i>.<i>) aureus</i> is a common causative agent of bacterial endophthalmitis, a vision threatening complication of eye surgeries. The relative contribution of <i>S</i>. <i>aureus </i>virulence factors in the pathogenesis of endophthalmitis remains unclear. Here, we comprehensively analyzed the development of intraocular inflammation, vascular permeability, and the loss of retinal function in C57BL/6 mouse eyes, challenged with live <i>S</i>. <i>aureus</i>, heat-killed <i>S</i>. <i>aureus </i>(HKSA), peptidoglycan (PGN), lipoteichoic acid (LTA), staphylococcal protein A (SPA), α-toxin, and Toxic-shock syndrome toxin 1 (TSST1). Our data showed a dose-dependent (range 0.01 μg/eye to 1.0 μg/eye) increase in the levels of inflammatory mediators by all virulence factors. The cell wall components, particularly PGN and LTA, seem to induce higher levels of TNF-α, IL-6, KC, and MIP2, whereas the toxins induced IL-1β. Similarly, among the virulence factors, PGN induced higher PMN infiltration. The vascular permeability assay revealed significant leakage in eyes challenged with live SA (12-fold) and HKSA (7.3-fold), in comparison to other virulence factors (~2-fold) and controls. These changes coincided with retinal tissue damage, as evidenced by histological analysis. The electroretinogram (ERG) analysis revealed a significant decline in retinal function in eyes inoculated with live SA, followed by HKSA, SPA, and α-toxin. Together, these findings demonstrate the differential innate responses of the retina to <i>S</i>. <i>aureus</i> virulence factors, which contribute to intraocular inflammation and retinal function loss in endophthalmitis.</p></div

Fundus imaging of eyes challenged with <i>S</i>. <i>aureus</i> virulence factors.

<p>Eyes of C57BL/6 mice (4–6 per group) were inoculated intravitreally with <i>S</i>. <i>aureus</i> (5000 CFU/eye), HKSA (5x10⁵ CFU), or and the indicated virulence factors (0.1μg /eye). At 24h post infection, eyes were examined by fundus microscope and images were captured using Micron III. Angiography was performed by intraperitoneal injections of 2% fluorescent dye.</p

Effect of <i>S</i>. <i>aureus</i> virulence factors on inflammatory responses.

<p>Eyes of C57BL/6 mice (4–6 per group) were inoculated with indicated dose of heat-killed <i>S</i>. <i>aureus</i> (HKSA) (5X10⁵ CFU/eye), its cell wall components (PGN and LTA; 0.1μg each), and cell surface and secreted proteins (SPA, TSST, and α-toxin; 0.1μg each). After 24h, eyes (n = 6) were enucleated and subjected to ELISA, eyes injected with PBS served as controls. Statistical analysis was performed by using one way ANOVA with Dunnett’s multi-comparison test. *p <0.05, **p <0.005, ***p<0.0005.</p

Determination of vascular leakage in infected retina.

<p>To determine the vascular permeability, infected eyes were embedded in OCT at 24h and the cryosections were subjected to IHC analysis. Fluorescent densities for CD31 (Green, biomarker for blood vessels) and Fibrinogen (Red, released from blood into the retinal tissue) were measured. Fluorescent intensities were scanned in three different regions of the retina in each slide and an average of 3 to 4 retina in each treatment group. Fold change was calculated by calculating the ratio between CD31 (Vascular marker) and Fibrinogen (Leakage marker) and presented as mean ± SD. Statistical significance was determined by One way ANOVA with Dunnett’s multi-comparison test. ***<i>p</i><0.0005, **p<0.005, n = 6). Original magnification 20x.</p

Retinal function analysis in <i>S</i>. <i>aureus</i> virulence factors challenged eyes.

<p>Eyes of C57BL/6 mice (4–6 per group) were inoculated intravitreally with <i>S</i>. <i>aureus</i> (5000CFU), HKSA (5x10⁵ CFU), LTA (0.1μg), PGN (0.1μg), SPA (0.1μg), TSST1 (0.1μg), α-toxin (0.1μg), and PBS (2μl). ERG was performed after overnight dark adaptation. Electroretinogram responses to a 6-dB flash were recorded and the percentage amplitude of a- and b-wave retained in infected eyes was compared to that of uninjected mice control and presented as mean ± SD. ERG amplitudes Statistical analysis was performed using one-way ANOVA with Dunnett’s multi-comparison test. <i>*p</i> <0.05, <i>**p</i> <0.005, <i>***p</i> <0.001 (n = 6 mice were used per treatment). UN,uninjected.</p

Imidazo[1,2-<i>a</i>]pyridine-substituted coumarin as a selective ratiometric sensor for Cu²⁺ ion

<p>A novel fluorescent chemosensor, (<i>E</i>)-7-(diethylamino)-3-((2-phenylimidazo[1,2-<i>a</i>]pyridin-3-ylimino)methyl)-2<i>H</i>-chromen-2-one <b>1a</b>, has been synthesised and characterised. This chemosensor displayed an extreme selective fluorescence emission only with Cu²⁺ ion over all other metal ions examined. The Job’s plot experiment analysis suggested the binding ratio of the chemosensor <b>1a</b> with Cu²⁺ was 1:1 metal-to-ligand ratio. The association constant for Cu²⁺ towards receptor <b>1a</b> obtained from Benesi–Hildebrand plot was found to be 4.859 × 10³ M⁻¹ with a detection limit 4.6 × 10⁻⁸ M. Fluorescence enhancement caused by Cu²⁺ binding with chemosensor <b>1a</b> attributed to combinational effect of intramolecular charge transfer and chelation-enhanced fluorescence occurred at pH 8.0.</p

Synthesis of MoS₂ Nanoflowers for Photocatalytic Degradation of Organic Dyes

The MoS2 nanostructures have been synthesized with the variation of Mo/S molar ratios of 1:2, 1:3, 1:4, 1:5, and 1:6 using a simple hydrothermal method. The (002) peak at 2θ ∼ 14° in the X-ray diffraction (XRD) pattern confirms the hexagonal phase of the synthesized MoS2 nanostructures, which agrees well with Raman and high-resolution transmission electron microscopy study. Furthermore, field emission scanning electron microscopy analysis reveals that the synthesized MoS2 with Mo/S molar ratios of 1:5 and 1:6 exhibits a nanoflower-like structure, significantly enhancing the photocatalytic activity. The methylene blue (MB) and phenolphthalein dye degradation efficiencies and rate constants of MoS2 are enhanced with the rise of Mo/S molar ratio under sunlight illumination. Specifically, MoS2 nanoflowers with a 1:5 molar ratio showed the maximum MB dye degradation efficiency of 98% and a rate constant of 0.132 cm–1 in 25 min of sunlight illumination. In addition, a maximum photocurrent density of 22 mA/cm2 has been achieved at −0.6 V vs Ag/AgCl for a 1:5 molar ratio sample. Moreover, the lowest charge-transfer resistance, highest carrier density, and carrier mobility enhance the photocatalytic activity of the 1:5 molar ratio sample with better separation of charge carriers and reduced carrier recombination rate. Hence, the synthesized MoS2 nanostructures with a 1:5 molar ratio of Mo/S are the optimized sample with enhanced photocatalytic and photoelectrochemical performances. The electronic and photocatalytic properties of MoS2 have been investigated theoretically with the variation of the layer number