A Survey on Personalized Recommendation Techniques

No Abstrac

A Novel Ant based Clustering of Gene Expression Data using MapReduce Framework

Genes which exhibit similar patterns are often functionally related. Microarray technology provides a unique tool to examine how a cells gene expression pattern chang es under various conditions. Analyzing and interpreting these gene expression data is a challenging task. Clustering is one of the useful and popular methods to extract useful patterns from these gene expression data. In this paper multi colony ant based clustering approach is proposed. The whole processing procedure is divided into two parts: The first is the construction of Minimum spanning tree from the gene expression data using MapReduce version of ant colony optimization techniques. The second part is clustering, which is done by cutting the costlier edges from the minimum spanning tree, followed by one step k - means clustering procedure. Applied to different file sizes of gene expression data over different number of processors, the proposed approach exhibits good scalability and accuracy

Exxon, Chevron and Conocophillips: 25 Years of Rejecting Shareholder Concerns on Climate Change

The resolutions included in this list are focused on climate change, including carbon reductions, climate expertise on boards, related market shifts that could hurt companies' stock value and lobbying/political efforts that work against climate solutions. We excluded several kinds of proposals that were not explicitly climate related, even though they were relevant to climate change. Among the exclusions: resolutions on hydraulic fracturing, drilling in the Arctic election contributions, and the ability of shareholders to nominate board members

Characterization of silver-kaolinite (AgK): an adsorbent for long-lived 129I species

Bentonite is a preferred buffer and backfill material for deep geological disposal of high-level nuclear waste (HLW). Bentonite does not retain anions by virtue of its negatively charged basal surface. Imparting anion retention ability to bentonite is important to enable the expansive clay to retain long-lived I-129 (iodine-129; half-life = 16 million years) species that may escape from the HLW geological repository. Silver-kaolinite (AgK) material is prepared as an additive to improve the iodide retention capacity of bentonite. The AgK is prepared by heating kaolinite-silver nitrate mix at 400 degrees C to study the kaolinite influence on the transition metal ion when reacting at its dehydroxylation temperature. Thermo gravimetric-Evolved Gas Detection analysis, X-ray diffraction analysis, X-ray photo electron spectroscopy and electron probe micro analysis indicated that silver occurs as AgO/Ag2O surface coating on thermally reacting kaolinite with silver nitrate at 400 degrees C

X-RAY DOSE DEPENDENCE OF DARK CURRENT IN AMORPHOUS SELENIUM-ALLOY X-RAY PHOTOCONDUCTORS

The dark current is an important characteristic of a photoconductive X-ray detector, and can impact the dynamic range of the detector and its detective quantum efficiency. It is therefore essential that the dark current and its behavior with time and x-ray irradiation are well characterized and understood in amorphous selenium (a-Se) X-ray detectors for the future enhancement of these detectors. Throughout the course of this work, the dark current in practical a-Se multilayer photoconductors were studied as function of time and x-ray dose delivered to the detector material. The dark current in these multilayer structures has been measured as a function of different rest time periods, sample structure, single X-ray irradiation on the sample and multiple irradiation on the sample. Experiments were performed by resting the sample in dark for a period of time (24 hours) and then samples were exposed to X-ray radiation. It has been observed that most of the trapped charge carriers in the bulk of the material are discharged after resting the sample in dark for 24 hours. It was observed that multilayer sample structures p-i-n and n-i-p exhibit much less dark current compared to other samples with single layer and double layer structures, that is, i-layer only, n-i and p-i structures. The experiments support that the dark current is controlled by injection of charge carriers from contacts. Single X-ray irradiation and multiple irradiation experiments were performed on multilayer a-Se photoconductors at a dose rate of 0.51 Gy s-1 with an exposure duration of 3 s. Samples were exposed to single irradiation at 100 s and 400 s. The dark current following the photocurrent was recorded. Multiple irradiation experiments were also performed on these multilayer samples. With different reverse bias voltages, samples were irradiated 10 times from 200s to 2000s. It was found that the dark current tends to increase with repeated X-ray irradiation but the increase depends on the applied reverse bias; the increase is negligible at a field of 10 V μm-1. After the cessation of the irradiation, the dark current decays and tends to reach a steady state value at t = 4000s. After 24 hr of resting in the dark, the dark current was nearly as low as the original dark current before the X-ray irradiatio

Biosynthesis and characterization of silver nanoparticles using ginger spent and their antibacterial activity

Ginger spent is the byproduct of spice industries that remove the essential oils of ginger (Zingiber officinale) for food industry and medicinal purposes. Ginger is a well known spice used often for seasoning in Indian cuisine. The de-oiled ginger has no specific use mostly goes to waste. Hence, we utilized this industrial waste product in the efficient synthesis of silver nanoparticles with the aid of UV irradiation from a solution of 1mM silver nitrate and spent extract in the ratio 9:1. Immediate colour change from pale yellow to dark brown was noted indicating the rapid synthesis of silver nanoparticles. These nanoparticles were centrifuged, dried and well characterized. UV Vis Spectroscopy, XRD analysis, Zeta potential and SEM analysis was carried out. It was commendable that the size of the nanoparticles fell well within the upper limit of 100nm. Agar well diffusion method was used to screen the antimicrobial activity of the well characterized silver nanoparticles. They were tested against seven pathogenic strains of three gram negative bacteria (Escherichia coli, Klebsiella pneumonia and Pseudomonas aeruginosa) three gram positive bacteria(Bacillus subtilis, Staphylococcus aureus and Streptococcus faecalis) and a fungus (Candida  albicans). It was seen that the zone of inhibition(ZOI) in well plate method  increased on increasing the concentration of silver nanoparticles. Further studies could lead to the application of these silver nanoparticles in medicine