Symmetric Subresultants and Applications

Schur's transforms of a polynomial are used to count its roots in the unit disk. These are generalized them by introducing the sequence of symmetric sub-resultants of two polynomials. Although they do have a determinantal definition, we show that they satisfy a structure theorem which allows us to compute them with a type of Euclidean division. As a consequence, a fast algorithm based on a dichotomic process and FFT is designed. We prove also that these symmetric sub-resultants have a deep link with Toeplitz matrices. Finally, we propose a new algorithm of inversion for such matrices. It has the same cost as those already known, however it is fraction-free and consequently well adapted to computer algebra

Direct strain and slope measurement using 3D DSPSI

This communication presents a new implementation of DSPSI. Its main features are 1. an advanced model taking into account the beam divergence, 2. the coupling with a surface shape measurement in order to generalize DSPSI to nonplanar surfaces 3. the use of small shear distance made possible using a precise measurement procedure. A first application on a modified Iosipescu shear test is presented and compared to classical DIC measurements

Direct strain and slope measurement using 2D DSPSI Title

Large variety of optical full-field measurement techniques are being developed and applied to solve mechanical problems. Since each technique possess its own merits, it is important to know the capabilities and limitations of such techniques. Among these optical full-field methods, interferometry techniques take an important place. They are based on illumination with coherent light (laser). In shearing interferometry the difference of the out of-plane displacement in two neighboring object points is directly measured. Since object displacement does not result in interferometry fringes, the method is suited for localization of strain concentrations and is indeed used in industry for this purpose. Used quantitatively DSPSI possesses the advantage over conventional out-of-plane displacement-sensitive interferometry that only a single difference of the unwrapped phase map is required to obtain flexural strains, thereby relieving problems with noise and reduction in the field of view. The first publication on (DSPSI) was made in 1973, but the emergence of a system providing quantitative measurements is more recent. This work aims to present the results of strain measurements using digital speckle pattern shearing interferometry (DSPSI).Comment: Communication \`a la Conf\'erence M\'editerran\'eenne sur les Mat\'eriaux Innovants et Applications -CIMA, Beyrouth, Liban-Mars 15-17, 2011; JM-CIMA.pd

Imaginer la visibilité politique du Corps du Christ généré par l’Eucharistie

À la suite d’un séjour au Chili sous le régime d’A. Pinochet, W. Cavanaugh élabore une théologie politique à partir d’une ecclésiologie sacramentaire qui souligne que la liturgie eucharistique réalise le corps sacramentel du Christ comme corps de salut dans le corps social. L’article discute de l’intérêt théologique de cette approche du point de vue de la visibilité politique du corps ecclésial.Following a stay in Chile during A. Pinochet’s ruling, W. Cavanaugh works out a political theology based on a sacramentary ecclesiology which which presents the Eucharistic liturgy as a realization of the Body of salvation in Christ in the social body. The paper discusses the theological interest of this approach from the point of view of the political visibility of the ecclesial body

Video-rate laser Doppler vibrometry by heterodyne holography

We report a demonstration video-rate heterodyne holography in off-axis configuration. Reconstruction and display of 1 Megapixel holograms is achieved at 24 frames per second, with a graphics processing unit. Our claims are validated with real-time screening of steady-state vibration amplitudes in a wide-field, non-contact vibrometry experiment.Comment: Optics Letters (2011) 00

Desenvolupat un nou sistema per detectar i tractar el plom d'aigües contaminades

La major part de les tècniques per a la detecció de metalls tòxics desenvolupades fins el moment necessita aparells cars i personal especialitzat. Darrerament, però, s'ha començat a estudiar l'ús de diverses nanopartícules que permeten treballar amb menys costos monetaris i ambientals. Recentment s'ha desenvolupat un nou sistema basat en nanoestructures de calcita-polietilenamina que permet detectar baixes concentracions de plom d'aigües contaminades i eliminar-ne una major quantitat que sistemes més antics.La mayor parte de las técnicas para la detección de metales tóxicos desarrolladas hasta el momento necesita aparatos caros y personal especializado. Últimamente, sin embargo, se ha comenzado a estudiar el uso de diversas nanopartículas que permiten trabajar con menos costes monetarios y ambientales. Recientemente se ha desarrollado un nuevo sistema basado en nanoestructuras de calcita-polietilenamina que permite detectar bajas concentraciones de plomo de aguas contaminadas y eliminar una mayor cantidad que sistemas más antiguos.Most of the techniques for the detection of toxic metals developed up to now require expensive equipment and skilled personnel. Lately, however, the use of various nanoparticles which can work with less environmental and monetary costs has begun to be explored. Recently a new system based on calcite-polietilenamina nanostructures was created to detect low concentrations of lead-contaminated water and eliminate a greater amount than older systems

Metabolic engineering of Bacillus subtilis toward the efficient and stable production of C30-carotenoids

Commercial carotenoid production is dominated by chemical synthesis and plant extraction, both of which are unsustainable and can be detrimental to the environment. A promising alternative for the mass production of carotenoids from both an ecological and commercial perspective is microbial synthesis. To date, C30 carotenoid production in Bacillus subtilis has been achieved using plasmid systems for the overexpression of biosynthetic enzymes. In the present study, we employed a clustered regularly interspaced short palindromic repeat-Cas9 (CRISPR-Cas9) system to develop an efficient, safe, and stable C30 carotenoid-producing B. subtilis strain, devoid of plasmids and antibiotic selection markers. To this end, the expression levels of crtM (dehydrosqualene synthase) and crtN (dehydrosqualene desaturase) genes from Staphylococcus aureus were upregulated by the insertion of three gene copies into the chromosome of B. subtilis. Subsequently, the supply of the C30 carotenoid precursor farnesyl diphosphate (FPP), which is the substrate for CrtMN enzymes, was enhanced by expressing chromosomally integrated Bacillus megaterium-derived farnesyl diphosphate synthase (FPPS), a key enzyme in the FPP pathway, and abolishing the expression of farnesyl diphosphate phosphatase (YisP), an enzyme responsible for the undesired conversion of FPP to farnesol. The consecutive combination of these features resulted in a stepwise increased production of C30 carotenoids. For the first time, a B. subtilis strain that can endogenously produce C30 carotenoids has been constructed, which we anticipate will serve as a chassis for further metabolic engineering and fermentation optimization aimed at developing a commercial scale bioproduction process

Nou estudi de la coordinació de lligands pirazòlics a Pt(II)

Mitjançant diferents tècniques analítiques i espectroscòpiques, s'ha pogut determinar l'estructura de diversos complexos de coordinació de Pt(II) amb lligands pirazòlics substituïts. Els resultats d'aquesta anàlisi estructural s'han obtingut a partir d'una sèrie d'estudis de RMN de 1H, 13C{1H} i 195Pt{1H}, donant un pas més en el progrés de la Química de Coordinació

Compostos de zinc i cadmi que presenten propietats fotoluminiscents

En l'actualitat la indústria en tots els seus sectors requereix de la creació de nous productes per a noves aplicacions. La Química Inorgànica i més concretament els compostos de coordinació per la seva gran diversitat estructural i gran nombre de propietats prenen una notable rellevància en el desenvolupament de nous compostos magnètics, nous fàrmacs com a catalitzadors, entre d'altres. Investigadors de la UAB han estudiat compostos de Zn(II) i Cd(II) mitjançant tècniques analítiques i espectroscòpiques, demostrant que els compostos de Cd(II) són més fotoluminiscents que els de Zn(II) i que el grau de luminescència depèn a més de la piridil-amina utilitzada.En la actualidad la industria en todos sus sectores demanda de la creación de nuevos productos para nuevas aplicaciones. La Química Inorgánica y más concretamente los compuestos de coordinación debido a su gran diversidad estructural y gran número de propiedades adquiere una notable relevancia en el desarrollo de nuevos compuestos magnéticos, de nuevos fármacos, como catalizadores, entre otras. Investigadores de la UAB han estudiado compuestos de Zn(II) y Cd(II) mediante técnicas analíticas y espectroscópicas, demostrando que los compuestos de Cd(II) son más fotoluminiscentes que los de Zn(II) y que el grado de luminiscencia depende de la piridil-amina utilizada.Nowadays, the industry in all its sectors demands the creation of new products for new applications. Inorganic Chemistry and more precisely the coordination compounds due to their great structural diversity and large number of properties acquire a remarkable relevance in the development of new magnetic compounds, new drugs, as catalysts, among others. Researchers at the UAB have studied Zn (II) and Cd (II) compounds using analytical and spectroscopic techniques, demonstrating that Cd (II) compounds are more photoluminescent than Zn (II) ones and that the degree of luminescence depends on The pyridyl amine used