De Dimensión al FRiP : La empresa cultural y la política revolucionaria

Fil: Volontè, Fernanda. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina

Subdivision schemes for curve design and image analysis

Subdivision schemes are able to produce functions, which are smooth up to pixel accuracy, in a few steps through an iterative process. They take as input a coarse control polygon and iteratively generate new points using some algebraic or geometric rules. Therefore, they are a powerful tool for creating and displaying functions, in particular in computer graphics, computer-aided design, and signal analysis. A lot of research on univariate subdivision schemes is concerned with the convergence and the smoothness of the limit curve, especially for schemes where the new points are a linear combination of points from the previous iteration. Much less is known for non-linear schemes: in many cases there are only ad hoc proofs or numerical evidence about the regularity of these schemes. For schemes that use a geometric construction, it could be interesting to study the continuity of geometric entities. Dyn and Hormann propose sufficient conditions such that the subdivision process converges and the limit curve is tangent continuous. These conditions can be satisfied by any interpolatory scheme and they depend only on edge lengths and angles. The goal of my work is to generalize these conditions and to find a sufficient constraint, which guarantees that a generic interpolatory subdivision scheme gives limit curves with continuous curvature. To require the continuity of the curvature it seems natural to come up with a condition that depends on the difference of curvatures of neighbouring circles. The proof of the proposed condition is not completed, but we give a numerical evidence of it. A key feature of subdivision schemes is that they can be used in different fields of approximation theory. Due to their well-known relation with multiresolution analysis they can be exploited also in image analysis. In fact, subdivision schemes allow for an efficient computation of the wavelet transform using the filterbank. One current issue in signal processing is the analysis of anisotropic signals. Shearlet transforms allow to do it using the concept of multiple subdivision schemes. One drawback, however, is the big number of filters needed for analysing the signal given. The number of filters is related to the determinant of the expanding matrix considered. Therefore, a part of my work is devoted to find expanding matrices that give a smaller number of filters compared to the shearlet case. We present a family of anisotropic matrices for any dimension d with smaller determinant than shearlets. At the same time, these matrices allow for the definition of a valid directional transform and associated multiple subdivision schemes

La simulazione medica nel futuro: un tentativo di visioning The health simulation in the future: an attempt of visioning

La pratica clinica è un componente indispensabile dell’apprendimento e del mantenimento delle competenze in molte delle discipline sanitarie e la simulazione offre l’opportunità di praticare in maniera sicura ed efficace senza rischi per il paziente. La simulazione nella didattica medica si è già ampiamente evoluta rispetto alle sue fasi iniziali. L’introduzione dei simulatori di pazienti umani, intorno alla fine del XX secolo, rappresenta una tappa fondamentale nella scienza dell’educazione in sanità. Fino ad oggi l’attenzione degli sviluppatori si è concentrata da un lato sulla capacità dei simulatori di dare feedback verosimili e coerenti con il comportamento del paziente e con la fisiologia umana e dall’altro sull’interazione fra simulatore e utilizzatore. Le emergenti tecnologie nel campo della percezione sensoriale apporteranno miglioramenti significativi sia nella formazione in simulazione che nella gestione della simulazione stessa. Basandosi sull’analisi delle tecnologie attualmente disponibili e in via di sviluppo, questo scritto vuole essere uno sforzo di visioning sul futuro delle tecniche di simulazione. Nano-sensori e nano-attuatori, usati nella realtà aumentata/virtuale/ mista, permetteranno sia la concettualizzazione di sistemi capaci di aumentare il livello di realismo e di immersione sensoriale ma anche di mappare i movimenti e le azioni al fine di generare protocolli univoci di intervento. Proiettandoci in un ipotetico 2025, la simulazione medica sarà un’esperienza democratica, largamente accessibile, dinamica e immersiva a 360°, grazie alle tecniche di implementazione neuro-percettive.Practice is a key component of skills learning and maintenance in many health disciplines and simulation offers the opportunity to practice in a safe and effective manner improving patient safety. Simulation for healthcare training has already evolved through its initial historical phases. The introduction of human patient simulator toward the end of the 20th century was a milestone in health sciences education. To date the attention of developers has been paid to the capability of the simulator to give feedback, consistent with patient behavior and physiologic response, and the interaction between simulator and users. The emerging technologies in the field of sensorial perception will bring improvements both in education and in management of the simulation. Grounding on the analysis of current and under-development technology, the manuscript is an attempt of visioning simulation-based training in health education in a coming future. Nano-sensors and nano-actuators, used in augmented/virtual/mixed reality, will allow the conceptualization of systems increasing the level of realism and the sensorial immersion, and the mapping of movements and action in order to generate univocal protocols of intervention. Projecting ourselves in 2025, medical simulation will be a democratic, largely accessible, dynamic and 360° sensorial experience, thanks to techniques of neuro-perceptive implementation

La experiencia educativa en jardines comunitarios de la Provincia de Buenos Aires

Esta ponencia se propone dar cuenta de las características relevantes de la experiencia educativa de los jardines comunitarios que actualmente transitan un proceso de articulación con la cartera educativa del Estado Provincial. Se sitúan estas experiencias como una de las formas de acción colectiva impulsadas por los sectores más afectados durante las crisis económicas y sociales de los años 90 y también del 2001, que han coexistido con las acciones de protesta social emergentes en esos años. Este origen configura su carácter autogestionado y comunitario, rasgos que devienen identitarios, expresados en prácticas y discursos que permanecen aun en las instancias actuales de vinculación con agencias estatales. Los jardines comunitarios que han sido objeto de estaindagación son los que se encuentran actualmente vinculados con la DGCyE, por medio del "Programa de Apoyo y Acompañamiento a Experiencias Educativas de Nivel Inicial de Carácter Comunitario". Estas experiencias han comenzado como iniciativas barriales que con el tiempo se fueron organizando (en su mayoría) en redes de jardines comunitarios. Este trabajo recupera la indagación realizada desde la DGCyE (por medio de encuestas y entrevistas) al conjunto de 137 jardines comunitarios que han aceptado participar del citado ProgramaFil: Volontè, Fernanda. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.Fil: Ponce de León, Mercedes Aldana. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación. Instituto de Investigaciones en Humanidades y Ciencias Sociales (UNLP-CONICET); Argentina

The COBRAS/SAMBA space mission

COBRAS/SAMBA is an ESA mission designed for extensive, accurate mapping of the anisotropies of the Cosmic Background Radiation, with angular sensitivity from sub-degree scales up to and overlapping with the COBE-DMR resolution. This will allow a full identification of the primordial density perturbations which grew to form the large-scale structures observed in the present universe. The COBRAS/SAMBA maps will provide powerful tests for the inflationary model and decisive answers on the origin of cosmic structure. A combination of bolometric and radiometric instrumentation will ensure the sensitivity and wide spectral coverage required for accurate foreground discrimination. A far-Earth orbit has been selected to minimize the unwanted emission from the Earth. The project is currently in the Phase A study within the European Space Agency M3 programme

Optimizing HIV-1 protease production in Escherichia coli as fusion protein

<p>Abstract</p> <p>Background</p> <p>Human immunodeficiency virus (HIV) is the etiological agent in AIDS and related diseases. The aspartyl protease encoded by the 5' portion of the <it>pol </it>gene is responsible for proteolytic processing of the <it>gag-pol </it>polyprotein precursor to yield the mature capsid protein and the reverse transcriptase and integrase enzymes. The HIV protease (HIV-1Pr) is considered an attractive target for designing inhibitors which could be used to tackle AIDS and therefore it is still the object of a number of investigations.</p> <p>Results</p> <p>A recombinant human immunodeficiency virus type 1 protease (HIV-1Pr) was overexpressed in <it>Escherichia coli </it>cells as a fusion protein with bacterial periplasmic protein dithiol oxidase (DsbA) or glutathione S-transferase (GST), also containing a six-histidine tag sequence. Protein expression was optimized by designing a suitable HIV-1Pr cDNA (for <it>E. coli </it>expression and to avoid autoproteolysis) and by screening six different <it>E. coli </it>strains and five growth media. The best expression yields were achieved in <it>E. coli </it>BL21-Codon Plus(DE3)-RIL host and in TB or M9 medium to which 1% (w/v) glucose was added to minimize basal expression. Among the different parameters assayed, the presence of a buffer system (based on phosphate salts) and a growth temperature of 37°C after adding IPTG played the main role in enhancing protease expression (up to 10 mg of chimeric DsbA:HIV-1Pr/L fermentation broth). GST:HIVPr was in part (50%) produced as soluble protein while the overexpressed DsbA:HIV-1Pr chimeric protein largely accumulated in inclusion bodies as unprocessed fusion protein. A simple refolding procedure was developed on HiTrap Chelating column that yielded a refolded DsbA:HIV-1Pr with a > 80% recovery. Finally, enterokinase digestion of resolubilized DsbA:HIV-1Pr gave more than 2 mg of HIV-1Pr per liter of fermentation broth with a purity ≤ 80%, while PreScission protease cleavage of soluble GST:HIVPr yielded ~ 0.15 mg of pure HIV-1Pr per liter.</p> <p>Conclusions</p> <p>By using this optimized expression and purification procedure fairly large amounts of good-quality HIV-1Pr recombinant enzyme can be produced at the lab-scale and thus used for further biochemical studies.</p

Cytogenetics of Premature Ovarian Failure: An Investigation on 269 Affected Women

The importance of X chromosome in the aetiology of premature ovarian failure (POF) is well-known but in many cases POF still remains idiopathic. Chromosome aneuploidy increase is a physiological phenomenon related to aging, but the role of low-level sex chromosome mosaicism in ovarian function is still undiscovered. Standard cytogenetic analysis was carried out in a total of 269 patients affected by POF: 27 chromosomal abnormalities were identified, including X chromosome and autosomal structural and numerical abnormalities. In 47 patients with 46,XX karyotype we performed interphase FISH using X alpha-satellite probe in order to identify X chromosome mosaicism rate. Aneuploidy rate in the patient group was significantly higher than the general population group. These findings underline the importance of X chromosome in the aetiology of POF and highlight the potential role of low-level sex chromosome mosaicism in ovarian aging that may lead to a premature onset of menopause

Acciones desarrolladas por el PRT-ERP durante el período 1970-1975 : Su vinculación con la población civil

En la presente ponencia, intentaremos elaborar una tipologia de actividades desarrolladas por la organización armada PRT-ERP, entre los años 1970 – 1975. También pretendemos reconstruir de modo general una periodizaciòn, que incorpore la modificación en el tipo y modalidad de las actividades desarrolladas por el PRT-ERP, desde sus inicios hasta su disolución. Como es conocido , el PRT-ERP es una de las organizaciones político – militares relevantes entre todas las que surgieron en los años 60 y 70 en la Argentina y crecieron después del Cordobazo, en un contexto de intensa conflictividad social . Estas cobran un papel cada vez mas significativo en la sociedad, conjuntamente con el proceso de radicalización de una variedad de actores sociales y políticos que rechazan el autoritarismo militar y esperan una transformación social. Nuestra pregunta inicial se orientaba a las formas diferentes de articulación entre los integrantes de las organizaciones armadas con la población, resultándonos revelador la afirmación realizada por historiadores y analistas respecto a la simpatía y aceptación de la guerrilla en diferentes sectores. Conociendo las actividades del PRT-ERP se pueden diferenciar algunas circunstancias en que la población se ve involucrada (“tomada”) en situaciones planeadas por la organización siguiendo sus fines particulares y otras situaciones en las que el vínculo se produce a partir de la simpatía, adhesión o incorporación a la organización.Jornadas realizadas junto con el I Encuentro Latinoamericano de Metodología de las Ciencias Sociales.Facultad de Humanidades y Ciencias de la Educació

Cancer-Initiating Cells from Colorectal cancer Patients Escape from T Cell-Mediated Immunosurveillance In Vitro through Membrane-Bound IL-4

Cancer-initiating cells (CICs) that are responsible for tumor initiation, propagation, and resistance to standard therapies have been isolated from human solid tumors, including colorectal cancer (CRC). The aim of this study was to obtain an immunological profile of CRC-derived CICs and to identify CIC-associated target molecules for T cell immunotherapy. We have isolated cells with CIC properties along with their putative non-CIC autologous counterparts from human primary CRC tissues. These CICs have been shown to display “tumor-initiating/stemness” properties, including the expression of CIC-associated markers (e.g., CD44, CD24, ALDH-1, EpCAM, Lgr5), multipotency, and tumorigenicity following injection in immunodeficient mice. The immune profile of these cells was assessed by phenotype analysis and by in vitro stimulation of PBMCs with CICs as a source of Ags. CICs, compared with non-CIC counterparts, showed weak immunogenicity. This feature correlated with the expression of high levels of immu- nomodulatory molecules, such as IL-4, and with CIC-mediated inhibitory activity for anti-tumor T cell responses. CIC-associated IL-4 was found to be responsible for this negative function, which requires cell-to-cell contact with T lymphocytes and which is impaired by blocking IL-4 signaling. In addition, the CRC-associated Ag COA-1 was found to be expressed by CICs and to represent, in an autologous setting, a target molecule for anti-tumor T cells. Our study provides relevant information that may contribute to designing new immunotherapy protocols to target CICs in CRC patient