Aprendizajes y prácticas educativas en las actuales condiciones de época: COVID-19

“Esta obra colectiva es el resultado de una convocatoria a docentes, investigadores y profesionales del campo pedagógico a visibilizar procesos investigativos y prácticas educativas situadas en el marco de COVI-19. La misma se inscribe en el trabajo llevado a cabo por el equipo de Investigación responsable del Proyecto “Sentidos y significados acerca de aprender en las actuales condiciones de época: un estudio con docentes y estudiantes de la educación secundarias en la ciudad de Córdoba” de la Facultad de Filosofía y Humanidades. Universidad Nacional de Córdoba. El momento excepcional que estamos atravesando, pero que también nos atraviesa, ha modificado la percepción temporal a punto tal que habitamos un tiempo acelerado y angustiante que nos exige la producción de conocimiento provisorio. La presente publicación surge como un espacio para detenernos a documentar lo que nos acontece y, a su vez, como oportunidad para atesorar y resguardar las experiencias educativas que hemos construido, inventado y reinventando en este contexto. En ella encontrarán pluralidad de voces acerca de enseñar y aprender durante la pandemia. Este texto es una pausa para reflexionar sobre el hacer y las prácticas educativas por venir”.Fil: Beltramino, Lucia (comp.). Universidad Nacional de Córdoba. Facultad de Filosofía y Humanidades. Escuela de Archivología; Argentina

Design and Optimisation of Image-Based Processes for Detail-Scale Acquisitions

Avere accesso a un sistema di acquisizione tridimensionale efficace ed economico costituisce spesso una richiesta ancora non del tutto soddisfatta per coloro che desiderano generare e divulgare modelli digitali di oggetti di piccole o piccolissime dimensioni. Con l’intento di poter rappresentare a grande scala geometrie e texture non sempre percepibili a occhio nudo, questo lavoro valuta innovative soluzioni hardware image-based per la restituzione di modelli digitali con un elevato potere di dettaglio. La possibilità di restituire una grande quantità di dati e a un rapporto di riproduzione maggiore di 1:1 è perseguita con l’ideazione di accessori specifici, progettati ad hoc per la fase di acquisizione, grazie ai quali diviene praticabile l’impiego scientifico di nuovi strumenti, i microscopi digitali portatili USB. Un’ulteriore attenzione è riposta, inoltre, nell’identificazione di un modello geometrico di camera compatibile con questi microscopi per l’individuazione e la verifica della distanza principale. Attraverso l’interazione di diverse competenze, il lavoro dimostra come il processo fotogrammetrico possa essere reso accessibile anche a dispositivi inizialmente non progettati per tali applicazioni, svelando nuove transizioni e possibilità di ricerca.Facultad de Ingenierí

Reconstrucción de una pequeña caja reductora planetaria usando conceptos de ingeniería inversa : Relevamiento, diseño y construcción de los engranajes con tecnología FDM

En el presente trabajo se relata la reconstrucción de una pequeña caja reductora planetaria de una hidrolavadora cuyos engranajes sufrieron el barrido de sus dientes en servicio por razones desconocidas. Siguiendo los principios de la ingeniería inversa se diseñan piezas de reemplazo construidas en ácido poliláctico (PLA) por impresión 3D con tecnología Fused Deposition Modeling (FDM). Si bien la selección del material está determinada por la escasa disponibilidad de otros materiales, al indagar la cuestión en la literatura específica se encuentra que el PLA viene demostrando su aptitud para la aplicación en trenes de engranajes de dimensiones reducidas. Se analizan también los criterios de diseño y se llega a la conclusión de que los lineamientos habitualmente utilizados para engranajes metálicos son parcialmente válidos para aplicarlos al diseño de engranajes plásticos. Para el diseño de las piezas a fabricar se usan herramientas de CAD paramétrico para obtener datos sobre el perfil de los dientes a partir de la única pieza que no ha sufrido daño: la corona. Habiendo construido los engranajes, la caja reductora reparada se encuentra actualmente en período de ensayos, por lo que en este trabajo se describen solamente las etapas de diseño y construcción quedando las conclusiones definitivas para futuros trabajos.Facultad de Ingenierí

Diseño y visualización en línea de modelos educativos tridimensionales orientados a la enseñanza de los sistemas de representación en Ingeniería

En el presente trabajo se retoma una de las líneas de trabajo de la Unidad de Investigación, Extensión y Transferencia Grupo de Ingeniería Gráfica Aplicada (UIDET GIGA) que articula con la cátedra Grafica para Ingeniería y Sistemas de Representación “C”: el diseño o creación de modelos digitales tridimensionales (MTD) para su visualización en entornos virtuales como recursos de aprendizaje de los sistemas de representación en las carreras de Ingeniería de la U.N.L.P. Las ejercitaciones sobre los núcleos temáticos de los sistemas de representación junto a las prácticas de croquizado y de Dibujo Asistido por Computadora (CAD) se constituyen en las principales actividades de aprendizaje de la cátedra. Tradicionalmente tanto el croquizado como el dibujo de planos en un sistema CAD se realizan a partir de piezas mecánicas reales. Pero ante el aumento progresivo de la matrícula, las piezas mecánicas reales con que cuenta la cátedra resultan insuficientes ante la necesidad de proveer a los estudiantes de modelos didácticos con el mismo nivel de dificultad morfológica. En esta oportunidad, se presentan los antecedentes y avances en relación a los MTD desarrollados con progresivos niveles de complejidad y su posibilidad de visualización en entornos de visualización gratuitos que permiten interactuar con los modelos 3D tanto en computadoras personales como en dispositivos móviles.Facultad de Ingenierí

p66Shc Deficiency in Chronic Lymphocytic Leukemia Promotes Chemokine Receptor Expression Through the ROS-Dependent Inhibition of NF-κB

The microenvironment of lymphoid organs is central to the pathogenesis of chronic lymphocytic leukemia (CLL). Within it, tumor cells find a favourable niche to escape immunosurveillance and acquire pro-survival signals. We have previously reported that a CLL-associated defect in the expression of the pro-apoptotic and pro-oxidant adaptor p66Shc leads to enhanced homing to and accumulation of leukemic cells in the lymphoid microenvironment. The p66Shc deficiency-related impairment in intracellular reactive oxygen species (ROS) production in CLL cells is causally associated to the enhanced expression of the chemokine receptors CCR2, CXCR3 and CCR7, that promote leukemic cell homing to both lymphoid and non-lymphoid organs, suggesting the implication of a ROS-modulated transcription factor(s). Here we show that the activity of the ROS-responsive p65 subunit of the transcription factor NF-κB was hampered in the CLL-derived cell line MEC-1 expressing a NF-κB-luciferase reporter following treatment with H2O2. Similar results were obtained when intracellular ROS were generated by expression of p66Shc, but not of a ROS-defective mutant, in MEC-1 cells. NF-κB activation was associated with increased expression of the chemokine receptors CCR2, CXCR3 and CCR7. Reconstitution of p66Shc in CLL cells normalized intracellular ROS and hampered NF-κB activation, which led to a decrease in the expression of these homing receptors. Our data provide direct evidence that the p66Shc-deficiency-related ROS depletion in CLL cells concurs to NF-κB hyperactivation and homing receptor overexpression, providing a mechanistic basis for the enhanced ability of these cells to accumulate in the pro-survival lymphoid niche

Leukemic cell-secreted interleukin-9 suppresses cytotoxic T cell-mediated killing in chronic lymphocytic leukemia

Abstract The tumor microenvironment (TME) plays a central role in the pathogenesis of chronic lymphocytic leukemia (CLL), contributing to disease progression and chemoresistance. Leukemic cells shape the TME into a pro-survival and immunosuppressive niche through contact-dependent and contact-independent interactions with the cellular components of the TME. Immune synapse (IS) formation is defective in CLL. Here we asked whether soluble factors released by CLL cells contribute to their protection from cytotoxic T cell (CTL)-mediated killing by interfering with this process. We found that healthy CTLs cultured in media conditioned by leukemic cells from CLL patients or Eμ-TCL1 mice upregulate the exhaustion marker PD-1 and become unable to form functional ISs and kill target cells. These defects were more pronounced when media were conditioned by leukemic cells lacking p66Shc, a proapoptotic adapter whose deficiency has been implicated in disease aggressiveness both in CLL and in the Eμ-TCL1 mouse model. Multiplex ELISA assays showed that leukemic cells from Eμ-TCL1 mice secrete abnormally elevated amounts of CCL22, CCL24, IL-9 and IL-10, which are further upregulated in the absence of p66Shc. Among these, IL-9 and IL-10 were also overexpressed in leukemic cells from CLL patients, where they inversely correlated with residual p66Shc. Using neutralizing antibodies or the recombinant cytokines we show that IL-9, but not IL-10, mediates both the enhancement in PD-1 expression and the suppression of effector functions in healthy CTLs. Our results demonstrate that IL-9 secreted by leukemic cells negatively modulates the anti-tumor immune abilities of CTLs, highlighting a new suppressive mechanism and a novel potential therapeutical target in CLL

DataSheet1_p66Shc deficiency in CLL cells enhances PD-L1 expression and suppresses immune synapse formation.docx

Introduction: Escape from immunosurveillance is a hallmark of chronic lymphocytic leukemia (CLL) cells. In the protective niche of lymphoid organs, leukemic cells suppress the ability of T lymphocytes to form the immune synapse (IS), thereby hampering T-cell mediated anti-tumoral activities. By binding its cognate receptor PD-1 at the surface of T lymphocytes, the inhibitory ligand PD-L1, which is overexpressed in CLL cells, mediates the T-cell suppressive activities of CLL cells. However, the molecular mechanism underlying PD-L1 overexpression in CLL cells remains unknown. We have previously reported a defective expression of the pro-apoptotic and pro-oxidant adaptor p66Shc in CLL cells, which is causally related to an impairment in intracellular reactive oxygen species (ROS) production and to the activation of the ROS-sensitive transcription factor NF-κB. The fact that PD-L1 expression is regulated by NF-κB suggests a mechanistic relationship between p66Shc deficiency and PD-L1 overexpression in CLL cells.Methods: 62 treatment-naive CLL patients and 43 healthy donors were included in this study. PD-L1 and p66Shc expression was quantified in B cells by flow cytometry and qRT-PCR. IS architecture and local signaling was assessed by flow cytometry and confocal microscopy. CD8+ cell killing activity was assessed by flow cytometry.Results: Here we show that residual p66Shc expression in leukemic cells isolated both from CLL patients and from the CLL mouse model Eμ-TCL1 inversely correlated with PD-L1 expression. We also show that the PD-L1 increase prevented leukemic cells from forming ISs with T lymphocytes. Reconstitution of p66Shc, but not of a ROS-defective mutant, in both CLL cells and the CLL-derived cell line MEC-1, enhanced intracellular ROS and decreased PD-L1 expression. Similar results were obtained following treatment of CLL cells with H2O2 as exogenous source of ROS, that normalized PD-L1 expression and recovered IS formation.Discussion: Our data provide direct evidence that the p66Shc-deficiency-related ROS depletion in CLL cells concurs to enhance PD-L1 expression and provides a mechanistic basis for the suppression of T cell-mediated anti-tumoral functions in the immunosuppressive lymphoid niche.</p

Multi-laboratory efforts for the standardization of performance assessment of diffuse optics instruments - The BitMap Exercise

A multi-laboratory exercise, involving 29 diffuse optical instruments, aimed at performance assessment of diffuse optics instruments on standardized protocols is presented. The overarching methodology and future actions will also be discussed.</p