492 research outputs found

    Osservazioni sul problema dell'enunciato in Sein und Zeit

    Get PDF
    El parágrafo 33 de Ser y tiempo conduce a la disolución de la concepción tradicional del juicio como núcleo fundamental de la lógica, mostrando como el juicio -en cuanto juicio apofántico- se asienta en una condición antepredicativa preliminar de tipo hermenéutico y pragmático. Sin embargo, en Ser y tiempo sigue sin resolverse el problema de un análisis específico sobre la naturaleza de las proposiciones acerca del ser del Dasein, proposiciones que son completamente distintas de las que se realizan en torno a los entes a la vista considerados en el mencionado parágrafo 33.Observations on the problem of proposition in Being and Time In the § 33 paragraph of Being and Time Heidegger leads to a dissolution of the traditional view of the judgement as the basic core of the logic, and points out that it, as apophantic proposition, results from a preliminary antepredicative -that is, hermeneutical and pragmatic- condition. Neverthless in Being and Time Heidegger leaves unsolved the problem of a specific inquiry upon the nature of propositions about the Being of Being-there, propositions that are quite distinct from the ones about the present-at-hand beings, considered in the § 33

    Simulation of light‐weight membrane structures by wrinkling model

    Get PDF
    The computational challenge in dealing with membrane systems is closely connected to the lack of bending stiffness that constitutes the main feature of this category of structures. This manifests numerically in badly conditioned or singular systems requiring the use of stabilized solution procedures, in our case of a ‘pseudo‐dynamic’ approach. The absence of the flexural stiffness makes the membrane very prone to local instabilities which manifest physically in the formation of little ‘waves’ in ‘compressed’ areas. Current work presents an efficient, sub‐iteration free ‘explicit’, penalty material based, wrinkling simulation procedure suitable for the solution of ‘static’ problems. The procedure is stabilized by taking full advantage of the pseudo‐dynamic solution strategy, which allows to retain the elemental quadratic convergence properties inside the single solution step. Results are validated by comparison with published results and by setting up ‘numerical experiments’ based on the solution of test cases using dense meshes. Copyright © 2005 John Wiley & Sons, Ltd.&nbsp

    Math Skills: a New Look from Functional Data Analysis

    Get PDF
    : Mental calculations involve various areas of the brain. The frontal, parietal and temporal lobes of the left hemisphere have a principal role in the completion of this typology of tasks. Their level of activation varies based on the mathematical competence and attentiveness of the subject under examination and the perceived difficulty of the task. Recent literature often investigates patterns of cerebral activity through fMRI, which is an expensive technique. In this scenario, EEGs represent a more straightforward and cheaper way to collect information regarding brain activity. In this work, we propose an EEG based method to detect differences in the cerebral activation level of people characterized by different abilities in carrying out the same arithmetical task. Our approach consists in the extraction of the activation level of a given region starting from the EEG acquired during resting state and during the completion of a subtraction task. We then analyze these data through Functional Data Analysis, a statistical technique that allows operating on biomedical signals as if they were functions. The application of this technique allowed for the detection of distinct cerebral patterns among the two groups and, more specifically, highlighted the presence of higher levels of activation in the parietal lobe in the population characterized by a lower performance

    An Edge-based Architecture for Phasor Measurements in Smart Grids

    Get PDF
    This paper investigates the application of Kubernetes and Edge computing technologies to operate IT services in the context of power systems and smart grids. Traditional services for grid monitoring such as Phasor Measurement Units (PMUs) and Phasor Data Concentrators (PDCs) require a centralized architecture and a rigid networking infrastructure in order to properly function, which today is only achieved at the High Voltage (HV) transmission level. Furthermore, manual intervention is often the only option for PMUs/PDCs maintenance. In this work, the traditional PMU/PDC services were deployed as docker-containers in a decentralized Kubernetes cluster, which can represent any kind of geographically dispersed TCP/IP network. By leveraging remote orchestration, several key benefits are achieved: (1) no manual reconfiguration of the PMU-PDC communications upon network reconfiguration, (2) automatic PMU traffic redirection in case of PDC service redeployment in a different location, and (3) reduced data-loss upon PDC failure and enhanced overall system resiliency due to minimized ICT services down-time

    Real-time reconstruction of long-lived particles at LHCb using FPGAs

    Full text link
    Finding tracks downstream of the magnet at the earliest LHCb trigger level is not part of the baseline plan of the upgrade trigger, on account of the significant CPU time required to execute the search. Many long-lived particles, such as KS0K^0_S and strange baryons, decay after the vertex track detector, so that their reconstruction efficiency is limited. We present a study of the performance of a future innovative real-time tracking system based on FPGAs, developed within a R\&D effort in the context of the LHCb Upgrade Ib (LHC Run~4), dedicated to the reconstruction of the particles downstream of the magnet in the forward tracking detector (Scintillating Fibre Tracker), that is capable of processing events at the full LHC collision rate of 30 MHz.Comment: ACAT 2019 proceedings. 7 pages, 2 figure

    Robust Passivity-Based Control of Boost Converters in DC Microgrids

    Get PDF
    This work deals with the design of a robust and decentralized passivity-based control scheme for regulating the voltage of a DC microgrid through boost converters. A Krasovskii-type storage function is proposed and a (local) passivity property for DC microgrids comprising unknown 'ZIP' (constant impedance 'Z', constant current 'I' and constant power 'P') loads is established. More precisely, the input port-variable of the corresponding passive map is equal to the first-time derivative of the control input. Then, the integrated input port-variable is used to shape the closed loop storage function such that it has a minimum at the desired equilibrium point. Convergence to the desired equilibrium is theoretically analyzed and the proposed control scheme is validated through experiments on a real DC microgrid

    Role of ventricular tachycardia ablation in arrhythmogenic right ventricular cardiomyopathy

    Get PDF
    Arrhythmogenic right ventricular cardiomyopathy (ARVC) is characterized by progressive fibro-fatty replacement of the myocardium that represents the substrate for recurrent sustained ventricular tachycardia (VT). These arrhythmias characterize the clinical course of a sizeable proportion of patients and have significant implications for their quality of life and long-term prognosis. Antiarrhythmic drugs are often poorly tolerated and usually provide incomplete control of arrhythmia relapses. Catheter ablation is a potentially effective strategy to treat frequent VT episodes and ICD shocks in ARVC patients. The aims of this review are to discuss the electrophysiological and electroanatomic substrates of ventricular tachycardia in patients with ARVC and to analyze the role of catheter ablation in their management with particular reference to selection of patients, technical issues, potential complications and outcomes

    FOXP1 circular RNA sustains mesenchymal stem cell identity via microRNA inhibition

    Get PDF
    Stem cell identity and plasticity are controlled by master regulatory genes and complex circuits also involving non-coding RNAs. Circular RNAs (circRNAs) are a class of RNAs generated from protein-coding genes by backsplicing, resulting in stable RNA structures devoid of free 5' and 3' ends. Little is known of the mechanisms of action of circRNAs, let alone in stem cell biology. In this study, for the first time, we determined that a circRNA controls mesenchymal stem cell (MSC) identity and differentiation. High-throughput MSC expression profiling from different tissues revealed a large number of expressed circRNAs. Among those, circFOXP1 was enriched in MSCs compared to differentiated mesodermal derivatives. Silencing of circFOXP1 dramatically impaired MSC differentiation in culture and in vivo. Furthermore, we demonstrated a direct interaction between circFOXP1 and miR-17-3p/miR-127-5p, which results in the modulation of non-canonical Wnt and EGFR pathways. Finally, we addressed the interplay between canonical and non-canonical Wnt pathways. Reprogramming to pluripotency of MSCs reduced circFOXP1 and non-canonical Wnt, whereas canonical Wnt was boosted. The opposing effect was observed during generation of MSCs from human pluripotent stem cells. Our results provide unprecedented evidence for a regulatory role for circFOXP1 as a gatekeeper of pivotal stem cell molecular networks

    Arrhythmogenic Right Ventricular Cardiomyopathy: Characterization of Left Ventricular Phenotype and Differential Diagnosis With Dilated Cardiomyopathy

    Get PDF
    Background This study assessed the prevalence of left ventricular (LV) involvement and characterized the clinical, electrocardiographic, and imaging features of LV phenotype in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC). Differential diagnosis between ARVC-LV phenotype and dilated cardiomyopathy (DCM) was evaluated. Methods and Results The study population included 87 ARVC patients (median age 34\ua0years) and 153 DCM patients (median age 51\ua0years). All underwent cardiac magnetic resonance with quantitative tissue characterization. Fifty-eight ARVC patients (67%) had LV involvement, with both LV systolic dysfunction and LV late gadolinium enhancement (LGE) in 41/58 (71%) and LV-LGE in isolation in 17 (29%). Compared with DCM, the ARVC-LV phenotype was statistically significantly more often characterized by low QRS voltages in limb leads, T-wave inversion in the inferolateral leads and major ventricular arrhythmias. LV-LGE was found in all ARVC patients with LV systolic dysfunction and in 69/153 (45%) of DCM patients. Patients with ARVC and LV systolic dysfunction had a greater amount of LV-LGE (25% versus 13% of LV mass; P<0.01), mostly localized in the subepicardial LV wall layers. An LV-LGE 6520% had a 100% specificity for diagnosis of ARVC-LV phenotype. An inverse correlation between LV ejection fraction and LV-LGE extent was found in the ARVC-LV phenotype (r=-0.63; P<0.01), but not in DCM (r=-0.01; P=0.94). Conclusions LV involvement in ARVC is common and characterized by clinical and cardiac magnetic resonance features which differ from those seen in DCM. The most distinctive feature of ARVC-LV phenotype is the large amount of LV-LGE/fibrosis, which impacts directly and negatively on the LV systolic function
    corecore