Conservative interpolation for the boundary integral solution of the Navier–Stokes equations

The Dual Reciprocity Method (DRM) is a technique to transform the domain integrals that appear in the boundary element method into equivalent boundary integrals. In this approach the non-linear terms are usually approximated by mathematical interpolation applied to the convective terms of the form of the Navier–Stokes equations. In this paper we introduce a conservative interpolation scheme that satisfies the continuity equation and performs better than pure mathematical interpolation. The new scheme together with a subdomain variation of the dual reciprocity method allows better approximation of the non-linear terms in the Navier–Stokes equations for moderate Reynolds number. Received: 21 January 2000     

Electrochemistry in large unilamellar vesicles. The distribution of 1-naphthol studied by square wave voltammetry

1-Naphthol (NPh) behavior in water and in large unilamellar vesicles (LUVs) formed with the phospholipid 1,2-di-oleoyl-sn-glycero-3-phosphatidylcholine (DOPC) was studied by square wave (SWV) and cyclic voltammetry (CV) techniques and, compared with emission spectroscopy studies. In DOPC LUV media, the redox behavior of NPh shows that the molecule undergoes a partition process between two pseudophases, the water and the LUV bilayer. The NPh electrochemical responses allow us to propose a model to explain the electrochemical experimental results and, in conjunction with our measurements, to calculate the NPh partition constant (K) value between the pseudophases. The K value coincides with the one obtained through emission spectroscopy. Beside the K value, our electrochemical model allows us to calculate the diffusion coefficient (D_LUV) for DOPC LUV which coincides with the D_LUV value obtained through dynamic light scattering (DLS). Thus, our data clearly show that the electrochemical measurements could be a powerful alternative approach to investigate the behavior of non-ionic electroactive molecules embed in a confined environment such as the LUV bilayer.     

Reciprocal Changes in miRNA Expression with Pigmentation and Decreased Proliferation Induced in Mouse B16F1 Melanoma Cells by l-Tyrosine and 5-Bromo-2′-Deoxyuridine

Background: Many microRNAs have been identified as critical mediators in the progression of melanoma through its regulation of genes involved in different cellular processes such as melanogenesis, cell cycle control, and senescence. However, microRNAs’ concurrent participation in syngeneic mouse B16F1 melanoma cells simultaneously induced decreased proliferation and differential pigmentation by exposure to 5-Brd-2′-dU (5’Bromo-2-deoxyuridine) and L-Tyr (L-Tyrosine) respectively, is poorly understood. Aim: To evaluate changes in the expression of microRNAs and identify which miRNAs in-network may contribute to the functional bases of phenotypes of differential pigmentation and reduction of proliferation in B16F1 melanoma cells exposed to 5-Brd-2′-dU and L-Tyr. Methods: Small RNAseq evaluation of the expression profiles of miRNAs in B16F1 melanoma cells exposed to 5-Brd-2′-dU (2.5 μg/mL) and L-Tyr (5 mM), as well as the expression by qRT-PCR of some molecular targets related to melanogenesis, cell cycle, and senescence. By bioinformatic analysis, we constructed network models of regulation and co-expression of microRNAs. Results: We confirmed that stimulation or repression of melanogenesis with L-Tyr or 5-Brd-2′-dU, respectively, generated changes in melanin concentration, reduction in proliferation, and changes in expression of microRNAs 470-3p, 470-5p, 30d-5p, 129-5p, 148b-3p, 27b-3p, and 211-5p, which presented patterns of coordinated and reciprocal co-expression, related to changes in melanogenesis through their putative targets Mitf, Tyr and Tyrp1, and control of cell cycle and senescence: Cyclin D1, Cdk2, Cdk4, p21, and p27. Conclusions: These findings provide insights into the molecular biology of melanoma of the way miRNAs are coordinated and reciprocal expression that may operate in a network as molecular bases for understanding changes in pigmentation and decreased proliferation induced in B16F1 melanoma cells exposed to L-Tyr and 5-Brd-2′-dU.     

Effect of Al and Ag dopants on the corrosion resistance of the AISI 316L-YSZ system

We present results for the deposition of coatings of zirconium stabilized with Yttria (YSZ) and doped with aluminum and silver. The coatings were grown from an YSZ ceramic target symmetrically covered with metallic (Al, Ag) pieces on AISI 316L steel substrates, via the RF sputtering technique. The microstructure of the coatings was characterized by means of X-ray diffraction (XRD), the chemical composition was determined through X-ray dispersive energy (EDX) analysis, and the electrochemical response was evaluated via impedance (EIS) and Tafel corrosion techniques. The XRD analysis showed that the coatings exhibited peaks belonging to the target material, dopant elements, and oxides such as Al₂O₃. Electrochemical analysis indicated an increase in the corrosion resistance of the coatings grown on aluminum oxide.     

Vertical-cavity surface-emitting lasers: Design, growth,fabrication, characterization

The authors have designed, fabricated, and tested vertical-cavity surface-emitting lasers (VCSEL) with diameters ranging from 0.5 μm to>50 μm. Design issues, molecular beam epitaxial growth, fabrication, and lasing characteristics are discussed. The topics considered in fabrication of VCSELs are microlaser geometries; ion implementation and masks; ion beam etching packaging and arrays, and ultrasmall devices     

Multigigabit/s operations of 16-wavelength vertical-cavity surface-emitting laser array

A multiple-wavelength 2*8 monolithic surface-emitting laser array with a potential aggregate array capacity of 80 Gb/s is reported. The high-speed packaging for the array was made possible with a slip-chip bonding technique, and each laser was capable of 5 Gb/s operation. The chirp-broadened 20-dB spectral width was less than 0.3 mm and the spectra occupied 16 independent wavelengths. Both optical and thermal crosstalks were very small, and the electrical crosstalk ranged from <-35 dB at <1 GHz, to -10 approximately -30 dB at 5 GHz.<>     

Multiple wavelength tunable surface-emitting laser arrays

Techniques to achieve wavelength multiplexing and tuning capabilities in vertical-cavity surface-emitting lasers (VCSELs) are described, and experimental results are given. The authors obtained 140 unique, uniformly separated, single-mode wavelength emissions from a 7×20 VCSEL array. Large total wavelength span (~ 430 Å) and small wavelength separation (~ 3 Å) are obtained simultaneously with uncompromised laser performance. All 140 lasers have nearly the same threshold currents, voltages, and resistances. Wavelength tuning is obtained by using a three-mirror coupled-cavity configuration. The three-mirror laser is a two-terminal device and requires only one top contact. Discrete tuning with a range as large as 61 Å is achieved with a small change in drive current of only 10.5 mA     

Genetic and environmental effects on chemical composition related to sensory traits in common beans (Phaseolus vulgaris L.)

The chemical composition determines plant-derived foods’ sensory traits; genetic and environmental effects and their interactions determine chemical composition. Understanding the importance of each factor should help characterise foodstuffs according to the variety and place of cultivation. We studied the effects of variety (five landraces + two checks) and environment (five locations and two years) on some molecules important for beans’ (Phaseolus vulgaris L.) sensory value. The greatest location effects were on protein and starch content and variety effects were due to combinations of traits (mainly sucrose, protein, and malic acid). The variety × location interactions detected in protein, sucrose, citric acid, and malic acid were difficult to associate to the gastronomic success of a particular variety cultivated at a particular location. Our results showed that protected designation of origin (PDO) in beans could be delimited on the basis of chemical composition, derived from the particular environmental characteristics of a region and the genetic characteristics of the varieties admitted.     

Crew Allocation System for the Masonry Industry

Masonry construction is labor‐intensive. Processes require a large number of crews made up of masons with diverse skills, capabilities, and personalities. Often crews are reassembled and the superintendent in the site is responsible for allocating crews to balance between the complexity of the job and the need for quality and high production rates. However, the masonry industry still faces increased time and low productivity rates that result from inefficiencies in crew allocation. This article presents a system for efficient crew allocation in the masonry industry formulated as a mixed‐integer program. The system takes into consideration characteristics of masons and site conditions and how to relate these to determine the right crew for the right wall to increase productivity. With the system, superintendents are not only able to identify working patterns for each of the masons but also optimal crew formation, completion times, and labor costs. To validate the model, data from a real project in the United States is used to compare the crew allocation completed by the superintendent onsite with the one proposed by the system. The results showed that relating characteristics of workers with site conditions had a substantial impact on reducing the completion time to build the walls, maximizing the utilization of masons, and outlining opportunities for concurrent work.     

Accurate ball trajectory tracking and 3D visualization for computer-assisted sports broadcast

The application of computer-aided controversial plays resolution in sport events significantly benefits organizers, referees and audience. Nowadays, especially in ball sports, very accurate technological solutions can be found. The main drawback of these systems is the need of complex and expensive hardware which makes them not affordable for less-known regional/traditional sports events. The lack of competitive systems with reduced hardware/software complexity and requirements motivates this research. Visual Analytics technologies permit system detecting the ball trajectory, solving with precision possible controversial plays. Ball is extracted from the video scene exploiting its shape features and velocity vector properties. Afterwards, its relative position to border line is calculated based on polynomial approximations. In order to enhance user visual experience, real-time rendering technologies are introduced to obtain virtual 3D reconstruction in quasi real-time. Comparing to other set ups, the main contribution of this work lays on the utilization of an unique camera per border line to extract 3D bounce point information. In addition, the system has no camera location/orientation limit, provided that line view is not occluded. Testing of the system has been done in real world scenarios, comparing the system output with referees’ judgment. Visual results of the system have been broadcasted during Basque Pelota matches.