What about the toxines analysis? new strategies for sensing applications using the chemistry of diazonium group

Objectives: Typically, the Mouse BioAssay (MBA) is a method widely used in many laboratories for analysis of marine biotoxins together with chromatographic (UPLC-MS) one [1]. The MBA will be banned from December 2014 by the amending Regulation (EC) Nº 2074/2005 of 10th January 2011. Based on this regulation, new alternative methods are required for fast detection of biotoxins in aquatic environment and in shellfish samples. The aim of this research work is to design and to characterize an electrochemical (bio)sensor for rapid and sensitive detection of biotoxins.Financial support from CRUP (E-136/12)-MICINN- International Projects - Mobility (PRI-AIBPT-2011-1096) and MEC (CTQ2011-28157

Deformations of canonical triple covers

In this paper, we show that if X is a smooth variety of general type of dimension m≥3 for which the canonical map induces a triple cover onto Y, where Y is a projective bundle over P1 or onto a projective space or onto a quadric hypersurface, embedded by a complete linear series (except Q3 embedded in P4), then the general deformation of the canonical morphism of X is again canonical and induces a triple cover. The extremal case when Y is embedded as a variety of minimal degree is of interest, due to its appearance in numerous situations. For instance, by looking at threefolds Y of minimal degree we find components of the moduli of threefolds X of general type with KX3=3pg−9,KX3≠6, whose general members correspond to canonical triple covers. Our results are especially interesting as well because they have no lower dimensional analogues

How Debian GNU/Linux is translated into Spanish

La Debian GNU/Linux és un dels paquets de programari per a Linux que compta amb una major distribució. Inclou milers de paquets de programari lliure (free, open source) provinents de moltes fonts diferents. Una de les peculiaritats del projecte Debian rau en el fet que funciona gràcies a un grup de voluntaris seleccionats per ells mateixos. En concret, això vol dir que les tasques de localització (inclosa la traducció) a moltes de les llengües previstes es duen a terme a partir de l'esforç de voluntaris. Aquest article descriu com es localitza el Debian al castellà, com a exemple dels esforços que s'estan fent en el món del programari lliure.La Debian GNU/Linux es uno de los paquetes de software para Linux que cuenta con una mayor distribución. Incluye miles de paquetes de software libre (free, open source) que provienen de muchas Fuentes diferentes. Una de las peculiaridades del proyecto Debian radical en el hecho de que funciona gracias a un grupo de voluntarios seleccionados por ellos mismos. En concreto, esto quiere decir que las tareas de localización (incluida la traducción) a muchas de las lenguas previstas se llevan a cabo a partir del esfuerzo de voluntarios. Este artículo describe cómo se localiza el Debian al castellano como ejemplo de los esfuerzos que es están realizando en el mundo del software libre.Debian GNU/Linux is one of the largest Linux-based software distributions, including thousands of libre (free, open source) software packages coming from many different sources. One of the peculiarities of the Debian project is being run altogether by a self-selected group of volunteers. In particular, this means that all the localization tasks (including translation) to the many supported languages is run on volunteer effort. This paper describes how Debian is localized to the Spanish language, as a case example of translation efforts in the libre software world

Deformations of canonical double covers

In this paper we show that if X is a smooth variety of general type of dimension m≥2 for which its canonical map induces a double cover onto Y, where Y is the projective space, a smooth quadric hypersurface or a smooth projective bundle over P1, embedded by a complete linear series, then the general deformation of the canonical morphism of X is again canonical and induces a double cover. The second part of the article proves the non-existence of canonical double structures on the rational varieties above mentioned. Our results have consequences for the moduli of varieties of general type of arbitrary dimension, since they show that infinitely many moduli spaces of higher dimensional varieties of general type have an entire “hyperelliptic” component. This is in sharp contrast with the case of curves or surfaces of lower Kodaira dimension

A new approach to domoic acid detection

The standard method for detection of marine toxins in bivalve is based on a mouse bioassay that presents several disadvantages such as its cost, non-specificity, time analysis and of course etic constraints. On the other hand regulation has been modified by the European Commission 15/2011 on January 10th, 2011, replacing Regulation (EC) No 2074/2005 and mouse bioassay will be banned from December 31, 2014. The development of new methods for a rapid screening for detection of toxins is highly needed. Electrochemical sensors are adequate for the development of user-friendly analytical methods that could therefore be used in a daily base by fisherman. In this work, we present a new strategy for the detection of domoic acid (amnesic toxin) based on the functionalization of carbon screen printed electrodes (SPE) and SPE modified with carbon nanotubes (CNTs). The functionalization is based in the immobilization of diazonium ion generated by the 4-nitroaniline diazotization with sodium nitrite in hydrochloridric acid. Although DA is not electroactive, it can be detected by means of a redox probe K4(FeCN)6, which electrochemical response depends on the concentration of DA immobilized on a functionalized SPE. Preliminary work has shown the possibility to carry out the immobilization without the use of bifunctional agents, such as carbodiimides, n-hydroxysuccinimide, that facilitates the bond between -NH2 and -COOH groups simplifying the design of the sensor. Experimental variables such as pH, temperature and time were optimized. Peak potential shift and enhancement of current intensity were analyzed

No surviving evolved companions to the progenitor of supernova SN 1006

Type Ia supernovae are thought to occur as a white dwarf made of carbon and oxygen accretes sufficient mass to trigger a thermonuclear explosion$^{1}$. The accretion could occur slowly from an unevolved (main-sequence) or evolved (subgiant or giant) star$^{2,3}$, that being dubbed the single-degenerate channel, or rapidly as it breaks up a smaller orbiting white dwarf (the double- degenerate channel)$^{3,4}$. Obviously, a companion will survive the explosion only in the single-degenerate channel$^{5}$. Both channels might contribute to the production of type Ia supernovae$^{6,7}$ but their relative proportions still remain a fundamental puzzle in astronomy. Previous searches for remnant companions have revealed one possible case for SN 1572$^{8,9}$, though that has been criticized$^{10}$. More recently, observations have restricted surviving companions to be small, main-sequence stars$^{11,12,13}$, ruling out giant companions, though still allowing the single-degenerate channel. Here we report the result of a search for surviving companions to the progenitor of SN 1006$^{14}$. None of the stars within 4' of the apparent site of the explosion is associated with the supernova remnant, so we can firmly exclude all giant and subgiant companions to the progenitor. Combined with the previous results, less than 20 per cent of type Iae occur through the single degenerate channel.Comment: Published as a letter in Nature (2012 September 27

Determining the nuclear neutron distribution from Coherent Elastic neutrino-Nucleus Scattering: current results and future prospects

Coherent elastic neutrino-nucleus scattering (CE$\nu$NS), a process recently measured for the first time at ORNL's Spallation Neutron Source, is directly sensitive to the weak form factor of the nucleus. The European Spallation Source (ESS), presently under construction, will generate the most intense pulsed neutrino flux suitable for the detection of CE$\nu$NS. In this paper we quantify its potential to determine the root mean square radius of the point-neutron distribution, for a variety of target nuclei and a suite of detectors. To put our results in context we also derive, for the first time, a constraint on this parameter from the analysis of the energy and timing data of the CsI detector at the COHERENT experiment.Comment: 16 pages, 4 figures. Minor text changes and references added. Matches version accepted by JHE