Life Gallery: event detection in a personal media collection

Multimedia Tools and Applications - Usage of camera-equipped mobile devices raises the need for automatically organizing large personal media collections. Event detection algorithms have been...     

Jet Mixing in Direct-Chill Casting of Aluminum: Crater Effects and its Consequence on Centerline Segregation

Recent reports have demonstrated the possibility of mitigating macrosegregation during the Direct-Chill casting of rolling slab ingots using an impinging jet. Herein, an analytical model is presented to predict the shape of the crater formed due to the impact of the jet on the slurry region. The model takes into account alloy composition, physical dimension, and casting speed on the distribution of forces and crater shape. The calculated shape of the crater profile is used to explain the centerline depletion in the impingement region previously reported.     

Influence of Yttrium on the Oxidation of Pure Iron at 973 K; Comparison Between Ion Implantation and Sol-Gel Coatings

The influence of yttrium introduced by ionimplantation or by sol-gel coatings on the oxidation ofpure iron has been studied at 973 K underp(O₂) = 0.04 Pa. The oxide scales wereexamined using a wide range of analytical techniques. The addition ofyttrium by ion implantation or by sol-gel coatingssignificantly improved the oxidation resistance of pureiron. This effect depends upon the introduction mode of yttrium on the surface.     

Effects of fasting and irradiation on the free amino acid content of Tribolium confusum J. Du Val. (Coleoptera: Tenebrionidae)

The aim of this study was to determine whether or not the change of the free amino acid (FAA) contents in irradiated Tribolium confusum male adults could be assigned to a lack of nutrition. The concentration of the amino acid pool (FAA) in Tribolium confusum males irradiated at 63, 315 and 504 Gy changed with time in nearly the same way as in insects deprived of food. This result confirms the inhibitory effect of irradiation on digestive functions. The time-course of FAA changes was dose independent from 63 to 504 Gy. No specific effect on intermediary metabolism was observed. The possibility of using FAA analysis to identify irradiated grains is discussed.     

Synthetic rat V1a vasopressin receptor fragments interfere with vasopressin binding via specific interaction with the receptor

To study the vasopressin receptor domains involved in the hormonal binding, we synthesized natural and modified fragments of V1a vasopressin receptor and tested their abilities to affect hormone-receptor interactions. Natural fragments mimicking the external loops one, two, and three were able to inhibit specific vasopressin binding to V1a receptor. In contrast, the natural N-terminal part of the V1a vasopressin receptor was found inactive. One fragment, derived from the external second loop and containing an additional C-terminal cysteine amide, was able to fully inhibit the specific binding of both labeled vasopressin agonist and antagonist to rat liver V1a vasopressin receptor and the vasopressin-sensitive phospholipase C of WRK1 cells. The peptide-mediated inhibition involved specific interactions between the V1a receptor and synthetic V1a vasopressin receptor fragment since 1) it was dependent upon the vasopressin receptor subtype tested (Ki(app) for the peptide: 3.7, 14.6, and 64.5 microM for displacing [3H]vasopressin from rat V1a, V1b, and V2 receptors, respectively; 2) it was specific and did not affect sarcosin 1-angiotensin II binding to rat liver membranes; 3) it was not mimicked by vasopressin receptor unrelated peptides exhibiting putative detergent properties; and 4) no direct interaction between [3H]vasopressin and synthetic peptide linked to an affinity chromatography column could be observed. Such an inhibition affected both the maximal binding capacity of the V1a vasopressin receptor and its affinity for the labeled hormone, depending upon the dose of synthetic peptide used and was partially irreversible. Structure-activity studies using a serie of synthetic fragments revealed the importance of their size and cysteinyl composition. These data indicate that some peptides mimicking extracellular loops of the V1a vasopressin receptor may interact with the vasopressin receptor itself and modify its coupling with phospholipase C.     

Comparing satellite remote sensing and ground network measurements for the production of site/time specific irradiance data

In this article, we compare the accuracy of satellite-derived time/site specific hourly irradiances, with that of irradiances obtained via extrapolation and/or interpolation of nearby ground-measuring stations. A comprehensive study undertaken by the International Energy Agency [Zelenka et al. Final Report of International Energy Agency Solar Heating and Cooling Program (1992)] had addressed this question, but had limited its scope to daily total irradiances. The present study focuses on hourly data.     

Dynamic Viscosity Modeling of Methane n-Decane and Methane Toluene Mixtures : Comparative Study of Some Representative Models

Viscosity measurements of well-defined mixtures are useful in order to evaluate existing viscosity models. Recently, an extensive experimental study of the viscosity at pressures up to 140 MPa has been carried out for the binary systems methane + n-decane and methane + toluene, between 293.15 and 373.15 K and for several methane compositions. Although very far from real petroleum fluids, these mixtures are interesting in order to study the potential of extending various models to the simulation of complex fluids with asymmetrical components (light/heavy hydrocarbon). These data (575 data points) have been discussed in the framework of recent representative models (hard sphere scheme, friction theory, and free volume model) and with mixing laws and two empirical models (particularly the LBC model which is commonly used in petroleum engineering, and the self-referencing model). This comparative study shows that the average absolute deviation of the models is between 3.8 and 49.8%, and the maximum deviation is between 11.6 and 78.4%, depending on the considered model.     

Palladium nanoparticle deposition via precipitation: a new method to functionalize macroporous silicon

We present an original two-step method for the deposition via precipitation of Pd nanoparticles into macroporous silicon. The method consists in immersing a macroporous silicon sample in a PdCl₂/DMSO solution and then in annealing the sample at a high temperature. The impact of composition and concentration of the solution and annealing time on the nanoparticle characteristics is investigated. This method is compared to electroless plating, which is a standard method for the deposition of Pd nanoparticles. Scanning electron microscopy and computerized image processing are used to evaluate size, shape, surface density and deposition homogeneity of the Pd nanoparticles on the pore walls. Energy-dispersive x-ray spectroscopy (EDX) and x-ray photoelectron spectroscopy (XPS) analyses are used to evaluate the composition of the deposited nanoparticles. In contrast to electroless plating, the proposed method leads to homogeneously distributed Pd nanoparticles along the macropores depth with a surface density that increases proportionally with the PdCl₂ concentration. Moreover EDX and XPS analysis showed that the nanoparticles are composed of Pd in its metallic state, while nanoparticles deposited by electroless plating are composed of both metallic Pd and PdO_x.