Isolating the chiral contribution in optical two-dimensional chiral spectroscopy using linearly polarized light

The full development of mono- or multi-dimensional time-resolved spectroscopy techniques incorporating optical activity signals has been strongly hampered by the challenge of identifying the small chiral signals over the large achiral background. Here we propose a new methodology to isolate chiral signals removing the achiral background from two commonly used configurations for performing two dimensional optical spectroscopy, known as BOXCARS and GRadient Assisted Photon Echo Spectroscopy (GRAPES). It is found that in both cases an achiral signal from an isotropic system can be completely eliminated by small manipulations of the relative angles between the linear polarizations of the four input laser pulses. Starting from the formulation of a perturbative expansion of the signal in the angle between the beams and the propagation axis, we derive analytic expressions that can be used to estimate how to change the polarization angles of the four pulses to minimize achiral contributions in the studied configurations. The generalization to any other possible experimental configurations has also been discussed. %We derive analytic expressions to changes required to the polarizations in terms of a perturbative expansion in the angle between the beams and the colinear axis. We also numerically estimate higher order coefficients which cover arbitrarily large angles and thus any experimental configuration.Comment: 7 figure

Facciamo il punto sull'Open Access : editori, ricercatori e specialisti dell’informazione si confrontano alla "First European Conference on Scientific Publishing in Biomedicine and Medicine" Lund, (Svezia) 21-22 aprile 2006

(Let's make the point on Open Access: publishers, researchers and information scientists meet at the "First European Conference on Scientific Publishing in Biomedicine and Medicine" Lund, (Sweden) 21-22 April 2006) Different aspects of the open access publishing model were discussed at conference in Lund by prestigious speakers, such as Eugene Garfield, Jean Paul Guedon, Stevan Harnad. In synthesis, the open access paradigm is deeply reshaping the scholarly communication system. Researchers are becoming gradually aware of OA impact so that the number of articles published on open access journals is increasing worldwide. Further efforts have to be done to promote authors' self-archiving of scientific works in the digital repositories set up on a large scale by research and academic institutions. The traditional publishing sector keeps to claim its role as producer of "official communication" by issuing prestigious journals, but in many cases offer the authors the choice of adopting both the author pay model or the subscription model to distribute their research outputs. Scientific publishing has been widely recognised as a "cost of research" and this fact should lead to guarantee free, permanent access to public funded research

Alphabetica e il reference digitale: suggerimenti e mappe concettuali per gli utenti del portale

Digital disintermediation is a process that involves many areas of social life: information, business, banking and also access to bibliographic information and knowledge. To the user who does not use the reference service in presence, it is necessary to offer new opportunities to expand the field of investigation through suggestions about authors or topics similar to made request.Alphabetica aims to provide a ‘hidden reference’, not with the logic of commercial algorithms, but by making full use of the tools of librarianship and enhancing the cooperative work of libraries belonging to the SBN network.La disintermediazione digitale è un processo che riguarda molteplici ambiti della vita sociale: quello dell’informazione, quello commerciale, quello bancario e anche quello di accesso alle informazioni bibliografiche e alla conoscenza. All’utente che non usufruisce del servizio di reference in presenza oppure online tramite i servizi del ‘chiedi al bibliotecario’ tradizionali o le instant chat, bisogna offrire delle opportunità per espandere il proprio campo di indagine attraverso dei suggerimenti che riguardano autori o argomenti affini a quelli oggetto della propria ricerca.Alphabetica si propone di fornire un ‘reference occultato’, non con le logiche degli algoritmi di tipo commerciale che suggeriscono risorse e argomenti con la medesima idea di fondo, ma sfruttando a pieno gli strumenti della biblioteconomia e valorizzando il lavoro cooperativo delle biblioteche aderenti al Servizio bibliotecario nazionale

A feasible and automatic free tool for T1 and ECV mapping

Purpose: Cardiac magnetic resonance (CMR) is a useful non-invasive tool for characterizing tissues and detecting myocardial fibrosis and edema. Estimation of extracellular volume fraction (ECV) using T1 sequences is emerging as an accurate biomarker in cardiac diseases associated with diffuse fibrosis. In this study, automatic software for T1 and ECV map generation consisting of an executable file was developed and validated using phantom and human data. Methods: T1 mapping was performed in phantoms and 30 subjects (22 patients and 8 healthy subjects) on a 1.5T MR scanner using the modified Look-Locker inversion-recovery (MOLLI) sequence prototype before and 15 min after contrast agent administration. T1 maps were generated using a Fast Nonlinear Least Squares algorithm. Myocardial ECV maps were generated using both pre- and post-contrast T1 image registration and automatic extraction of blood relaxation rates. Results: Using our software, pre- and post-contrast T1 maps were obtained in phantoms and healthy subjects resulting in a robust and reliable quantification as compared to reference software. Coregistration of pre- and post-contrast images improved the quality of ECV maps. Mean ECV value in healthy subjects was 24.5% ± 2.5%. Conclusions: This study demonstrated that it is possible to obtain accurate T1 maps and informative ECV maps using our software. Pixel-wise ECV maps obtained with this automatic software made it possible to visualize and evaluate the extent and severity of ECV alterations

Desigualdad, exclusión y justicia global

The process of globalization has affected the national State to the point of crisis and has increased inequality and exclusion in the world. Therefore, justice cannot keep being thought exclusively, as done in the past century, within certain limits all concerned to the State. Facing citizenship and State process of hierarchy in the new world order, a global justice theory must consider long-term the consolidation of a global constitutionalism that guarantees fundamental rights for everyone and promotes a fair distribution of the benefits generated by globalization.El proceso de globalización ha puesto en crisis al Estado-nación y ha incrementado la desigualdad y la exclusión en el mundo. Por ello, la justicia no puede seguir siendo pensada exclusivamente, como se hizo en tiempos pasados, a partir del estrecho margen estatal. Frente a la jerarquización de la ciudadanía y de los Estados en el nuevo orden mundial, una teoría de la justicia global debe plantearse a largo plazo la consolidación de un constitucionalismo global que garantice los derechos fundamentales para todas las personas y promueva una distribución justa de los beneficios que genera la globalización

Reason and history, beyond postmodernity

This paper recover some critical elements draw up from the postmodernity to the modern thinking in order to sketch, –beyond the modernity-postmodernity confrontation–, a concept of reason and history appropriate to our complex contemporary societies.En este artículo se recuperan algunos elementos de la crítica que formuló la posmodernidad al pensamiento moderno con el fin de esbozar, más allá del enfrentamiento modernidad-posmodernidad, un concepto de razón y de historia adecuados para nuestras complejas sociedades contemporáneas

Migración internacional y derechos fundamentales

To raise the matter of international migration it is necessary to start from the process of globalization and the current world order. After outlining some of the principal aspects of this process and order in which the increase of the migratory phenomenon is manifested –and on which the organization into a hierarchy of the national States and their corresponding citizenships stands out–, the necessity of the defense of the fundamental rights of the migrants is considered. This defense must be from a global perspective –beyond the States and the citizenships put into a hierarchy–, aiming to reach the establishment of the necessary international instruments that guarantee the application of these rights institutionally. In this sense, this article concludes with the raising of the appropriateness and urgency of global migratory politics that allow the governability of international migration.Para el abordaje del tema de la migración internacional se requiere partir del proceso de globalización y del orden mundial vigente. Después de delinear algunos de los principales aspectos de este proceso y orden en el que se manifiesta el incremento del fenómeno migratorio, y en el que se destaca especialmente la jerarquización de los Estados-nación y sus correspondientes ciudadanías, se plantea la necesidad de la defensa de los derechos fundamentales de los migrantes. Esta defensa debe ser a su vez desde una perspectiva global, más allá de los Estados y las ciudadanías jerarquizadas, con el fin de que se puedan llegar a establecer los instrumentos internacionales necesarios que garanticen institucionalmente el accionar de esos derechos. En este sentido, el artículo concluye con el planteamiento de la pertinencia y urgencia de una política migratoria global que permita la gobernanza de la migración internacional

NECOBELAC, a European project to promote the diffusion of scientific information in public health

NECOBELAC is a three-year Project started on February 1st 2009 and funded by the European Commission within the 7th Framework Program. NECOBELAC stands for Network of Collaboration Between Europe, Latin American and Caribbean Countries, and aims at enhancing the production and dissemination of quality scientific information in the field of public health. More precisely it focuses on two main objectives: 1) the promotion of training initiatives intended to improve the scientific writing skills of all professionals working in the health-related areas and 2) the implementation of scholarly communication systems based on the concept of immediate, open and permanent access to research results. The six partners involved in the Project are represented by academic and scientific institutions (from Italy (project coordinator), UK, Spain, Portugal, Brazil, and Colombia) which have gained sound experience in providing information services and outputs through networked initiatives. In this respect, the Project intends to raise awareness on shared principles of good practice among all stakeholders (authors, editors, publishers, information professionals, funding agencies, institutions, learning societies) of the scientific information chain and to promote a cultural change in the information production and dissemination process. The impact of the Project will be measured also by considering the outputs of the activities undertaken by the Project