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In this chapter, we review the recent theory of quantum diffusion models derived from the entropy minimization principle. These models are obtained by taking the moments of a collisional Wigner equation and closing the resulting system of equations by a quantum equilibrium. Such an equilibrium is defined as a minimizer of the quantum entropy subject to local constraints of given moments. We provide a framework to develop this minimization approach. The results of numerical simulations show that these models capture well the various features of quantum transport. [ABSTRACT FROM AUTHOR]

Abstract: Proteins very rarely act in isolation. Biomolecular interactions are central to all biological functions. In human, for example, interference with biomolecular networks often lead to disease. Protein–protein and protein–metabolite interactions have traditionally been studied one by one. Recently, significant progresses have been made in adapting suitable tools for the global analysis of biomolecular interactions. Here we review this suite of powerful technologies that enable an exponentially growing number of large-scale interaction datasets. These new technologies have already contributed to a more comprehensive cartography of several pathways relevant to human pathologies, offering a broader choice for therapeutic targets. Genome-wide scale analyses in model organisms reveal general organizational principles of eukaryotic proteomes. We also review the biochemical approaches that have been used in the past on a smaller scale for the quantification of the binding constant and the thermodynamics parameters governing biomolecular interaction. The adaptation of these technologies to the large-scale measurement of biomolecular interactions in (semi-)quantitative terms represents an important challenge. [Copyright &y& Elsevier]

This chapter illustrates how to decide between the application of parametric models (linear regression models) and non-parametric methods (additive models). The techniques applied in this chapter will use as explanatory variables some abiotic (temperature, salinity) and biotic (algal food biomass, as indicated by chlorophyll a) factors that affect the meroplanktonic larvae. We aim to provide preliminary information about some of the pre-settlement processes and the relative influences of environmental factors and variability. Also, the taxonomic identification of some decapod larvae is often difficult, and processing the samples is time consuming. By using information from the samples already analysed and the other available data, such as how many samples per year we could analyse, we may optimise the number of samples examined to achieve the best outcomes and interpretations. In this chapter we therefore also discuss how some models can be used to optimise the number of samples for further sample analysis in other years. [ABSTRACT FROM AUTHOR]

The problem of unidentified sources has been a recurrent one in the history of Astronomy. Soon after the opening of a new spectral window, the first objects detected through it are often poorly located and very difficult to associate with counterparts seen at other more familiar wavelengths, such as the optical band. As an example of this statement, we can recall the early times of Radioastronomy nearly half a century ago. In a historical paper by Baade and Minkowski [5], we can read: although the sources in Cassiopeia and Cygnus A are among the brightest and earliest-known radio sources of the sky, all attempts to identify them with astronomical objects in the visible range have failed so far. Some decades later, the unidentified source problem vanished thanks to the technical development of radio interferometers. Ironically, these instruments working at radio wavelengths provide today the most accurate positions of celestial bodies. The problem shifted to the domain of x-rays in the 1960s and 1970s of last century. Again, the technical progress solved it once more. Today x-ray observatories, such as Chandra or XMM, are able to deliver positions one to few arc-second accurate, thus becoming comparable to those from ground based optical telescopes. [ABSTRACT FROM AUTHOR]

In this paper we present a method for mapping 3D unknown environments from stereo images. It is based on a dense disparity image obtained by a process of window correlation. To each image in the sequence a geometrical rectification process is applied, which is essential to remove the conical perspective of the images obtained with a photographic camera. This process corrects the errors in coordinates x and y to obtain a better matching for the map information. The mapping method is an application of the geometrical rectification and the 3D reconstruction, whose main purpose is to obtain a realistic appearance of the scene. Keywords: Disparity images, Geometrical rectification, 3D mapping. [ABSTRACT FROM AUTHOR]

In this chapter, the properties of tailor-made anionic exchanger resins based on films of large polyethylenimine polymers (e.g., molecular weight 25,000) as supports for strong but reversible immobilization of proteins is shown. The polymer is completely coated, via covalent immobilization, the surface of different porous supports. Proteins can interact with this polymeric bed, involving a large percentage of the protein surface in the adsorption. Different enzymes have been very strongly adsorbed on these supports, retaining enzyme activities. On the other hand, adsorption is very strong and the derivatives may be used under a wide range of pH and ionic strengths. These supports may be useful even to stabilize multimeric enzymes, by involving several enzyme subunits in the immobilization. [ABSTRACT FROM AUTHOR]

Chemical modification and immobilization of proteins have been usually utilized as parallel techniques to improve enzyme stability. In this chapter, we show that chemical modification of the protein surface to greatly increase its reactivity with the groups of a support activated with glyoxyl residues may be a very good alternative for greatly increasing the protein stability via multipoint covalent attachment. For this purpose, some of the carboxylic acids of the proteins are transformed into amino groups by reaction with ethylendiamine via the carbodiimide coupling method. The new amino groups have a lower pK than Lys residues, enabling immobilization under milder conditions and a higher degree of stabilization. These results show that the coupling of different stabilization techniques may yield a synergistic effect, higher than any individual strategy. [ABSTRACT FROM AUTHOR]

The prospects of a new commercially available support (amino-epoxy-Sepabeads® ) for enzyme immobilization are discussed in this chapter. These supports have a layer of epoxy groups over a layer of ethylenediamine that is covalently bound to the support. Thus, the support has a high anionic exchanger power and a high number of epoxy groups. Some relevant properties of this support are (1) immobilization proceeds at low ionic strength using amino-epoxy-Sepabeads, (2) immobilization is much more rapid using amino-epoxy supports than employing conventional epoxy supports, and (3) stability of the immobilized enzyme has been found to be much higher using the new support than in preparations using the conventional ones in many cases. Therefore, this support may be a good complement to the traditional hydrophobic epoxy supports. [ABSTRACT FROM AUTHOR]

In this chapter, the combined use of the selectivity of metal chelate affinity chromatography with the capacity of epoxy supports to immobilize poly-His-tagged proteins via multipoint covalent attachment is shown. This has been achieved by designing tailor-made chelate-epoxy supports. In order to selectively adsorb the poly-His-tagged proteins, a very small density of Me-chelate groups was introduced in the epoxy supports. This allows for the retention of most of the epoxy groups available to multipointly react with the proteins. To reach the maximum support-enzyme reaction, after the first covalent immobilization process, the derivatives were incubated at alkaline pH conditions—where the nucleophile groups of the protein are more reactive. This protocol allows for the creation of immobilized preparations containing almost pure poly-His-tagged enzymes, even when using crude extracts, and enzymes much more stable than soluble ones. [ABSTRACT FROM AUTHOR]

The use of glutaraldehyde and supports containing primary amino groups is one of the most frequently used techniques for enzyme immobilization. However, glutaraldehyde is a very versatile reagent. Using low-ionic strength, the cationic nature of the surface permits the rapid ionic immobilization of the proteins. There are two different possibilities: (1) activate the support and immobilize the enzyme in a glutaraldehyde-activated support (in this case the immobilization is promoted by ionic exchange) or (2) adsorb the proteins on the aminated supports and treat the immobilized preparation with glutaraldehyde to cross-link both the enzyme and the support. Both alternatives have advantages and draw-backs that will be discussed on this chapter. [ABSTRACT FROM AUTHOR]

Video, image and signal processing applications show a high computational complexity and real-time restrictions. Hence they demand task distribution on DSP multi-computers. Unfortunately, DSP vendors offer these platforms nowadays with proprietary kernels and hardware specific communication libraries. As a result, current applications are hardware targeted and not portable at all. We understand that the use of MPI in the signal processing world should help to improve this scenery. This article describes a preliminary implementation of MPI for Sundance machines. Size and performance figures are given. Keywords: Digital signal processing, digital signal processors, DSP multicomputers, MPI, communication middleware. [ABSTRACT FROM AUTHOR]

The article discusses about high power ultrasound frequencies in electronics. Ultrasonic frequencies range from about 16 kHz up to 10 Hz to 10 Hz, that is up to frequencies with associated acoustic wavelengths comparable to intermolecular distances. This very broad frequency range provides a great variety of ultrasonic applications. Ultrasonic frequencies range from about 16 kHz up to 10 Hz to 10 Hz, that is, up to frequencies with associated acoustic wavelengths comparable to intermolecular distances. This very broad frequency range provides a great variety of ultrasonic applications. High-intensity ultrasound waves are finite-amplitude waves and their effects are generally linked to nonlinear phenomena produced during their propagation.

With the development of Electronic Commerce (EC), the need of offering brokerage facilities in a distributed environment has arisen. Customers need, in many situations, systems (broker agents) that simplify them the access to the different products and services provided by suppliers. On the other hand, the existence of brokers increases the globality of EC, since customers are even more unaware of the location of their final goods providers. To help on this, several brokerage systems are being developed in different contexts. However, how to organise broker agents in a distributed EC environment is not always being approached in the same way. This paper concentrates on this problem, and considers the different work in the field currently going on. A special focus is made on European research projects. This paper proposes several distributed models for Electronic Commerce, focussing on the case when brokerage facilities are included. In particular, we are proposing different models, i.e. a functional model, and operational model and an architectural model. In order to show the feasibility of the models, how they are applied to a specific implementation is shown. [ABSTRACT FROM AUTHOR]

We have studied in detail the properties of local active star-forming galaxies from the UCM survey, and in particular their star-formation histories. We have quantified the relative importance of the current episode of star formation in comparison to the underlying stellar populations. We have also determined the total stellar mass function and burst mass function for the UCM sample using a M/L calculated for each galaxy. Integrating this mass function we obtained a value for the stellar mass density of current star-forming galaxies in the local Universe. [ABSTRACT FROM AUTHOR]

We present a long-term project to study the characteristics and evolution of current star-forming galaxies at different redshifts. The selection of the samples is carried out in an homogeneous way by detecting Hα emission-line objects in deep images taken with narrow-band filters tuned to the corresponding wavelength for a given redshift. Target redshifts are z=0.24, z=0.4 and z=0.8. Here we present photometric redshifts, emission-line luminosities and multi-band photometry for a sample of emission-line galaxies at z=0.24, selected by their contrast in a narrow band filter centered in the 8200Å atmospheric window. The physical properties of these galaxies appear to be remarkably similar to those of local galaxies selected in the same way. Our results support the idea that the higher Star Formation Density measured at redshift z=0.24 is due to an increase of the density of bursting galaxies and not to an intrinsic change on overall galaxy properties. [ABSTRACT FROM AUTHOR]