Gli sviluppi della riflessione settecentesca sulla grazia nell'opera di Friedrich Schiller e Heinrich von Kleist

Nella mia tesi mi sono proposta di indagare e mettere a confronto alcune delle più importanti riflessioni filosofiche, estetiche e letterarie sul tema della grazia elaborate nel corso del Settecento da autori di lingua inglese, francese e tedesca e successivamente riprese da Friedrich Schiller e da Heinrich von Kleist. A tal fine, nel primo capitolo mi sono soffermata su alcuni scritti - o passi specifici - di autori quali Shaftesbury, Hogarth, Burke, Mendelssohn, Winckelmann, Kant e alcuni altri ancora, i quali hanno sovente inteso la grazia come una qualità al contempo etica ed estetica e cercato di definirla attraverso un costante confronto con la vicina nozione di bellezza. Nel secondo capitolo, ho preso in considerazione parte della produzione sia teatrale sia teorico-filosofica di Schiller per cercare di comprendere come quest'ultimo, anche attraverso un confronto diretto con alcuni degli autori precedentemente considerati, sia giunto ad intendere la grazia come espressione sensibile e corporea di sentimenti morali. Nel terzo ed ultimo capitolo, mi sono accostata alla produzione teatrale, narrativa e saggistica di Kleist per mostrare come, proprio a partire dalla ripresa di alcune acquisizioni schilleriane, egli se ne sia successivamente distanziato per arrivare infine a proporre una visione della grazia assai distante da quella portata avanti dallo stesso Schiller

Continuum elasticity theory of edge excitations in a two-dimensional electron liquid with finite range interactions

We make use of continuum elasticity theory to investigate the collective modes that propagate along the edge of a two-dimensional electron liquid or crystal in a magnetic field. An exact solution of the equations of motion is obtained with the following simplifying assumptions: (i) The system is {\it macroscopically} homogeneous and isotropic in the half-plane delimited by the edge (ii) The electron-electron interaction is of finite range due to screening by external electrodes (iii) The system is nearly incompressible. At sufficiently small wave vector $q$ we find a universal dispersion curve $\omega \sim q$ independent of the shear modulus. At larger wave vectors the dispersion can change its form in a manner dependent on the comparison of various length scales. We obtain analytical formulas for the dispersion and damping of the modes in various physical regimes.Comment: 3 figure

Propagating speed waves in flocks: A mathematical model

An efficient collective response to external perturbations is one of the most striking abilities of a biological system. One of the crucial aspect of this phenomenon is given by the information transfer, and resulting propagation of signals, within the group. In this respect the existence of density waves that propagate linearly on a flock of birds is well known. However, most aspects of this phenomenon are still not fully captured by theoretical models. In this work we present a model for the propagation of speed fluctuations inside a flock, which is able to reproduce the observed density waves. We study the full solution of the model in d=1, and we find a line in the parameter space along which the system relaxes as fast as possible without oscillating, resembling a generalized critical damping condition. By analyzing the parameters plane we show that this "critical damping" line indeed represents an attractor for a steepest descent dynamics of the return time of the system. Finally we propose a method to test the validity of the model through future experiments.Fil: Cavagnaro, Romina Andrea. Consiglio Nazionale delle Ricerche; ItaliaFil: Conti, Daniele. Università degli studi di Roma "La Sapienza; ItaliaFil: Giardina, Irene. Università degli studi di Roma "La Sapienza; ; ItaliaFil: Grigera, Tomas Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física de Líquidos y Sistemas Biológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física de Líquidos y Sistemas Biológicos; Argentin

Propagating speed waves in flocks: a mathematical model

An efficient collective response to external perturbations is one of the most striking abilities of a biological system. One of the crucial aspect of this phenomenon is given by the information transfer, and resulting propagation of signals, within the group. In this respect the existence of density waves that propagate linearly on a flock of birds is well known. However, most aspects of this phenomenon are still not fully captured by theoretical models. In this work we present a model for the propagation of speed fluctuations inside a flock, which is able to reproduce the observed density waves. We study the full solution of the model in d=1, and we find a line in the parameter space along which the system relaxes as fast as possible without oscillating, resembling a generalized critical damping condition. By analyzing the parameters plane we show that this "critical damping" line indeed represents an attractor for a steepest descent dynamics of the return time of the system. Finally we propose a method to test the validity of the model through future experiments.Instituto de Física de Líquidos y Sistemas Biológico

Double Thionated Pyrimidine Nucleobases: Molecular Tools with Tunable Photoproperties

Sulfur-substitutednucleobases are DNA and RNA base derivativesthat exhibit extremely efficient photoinduced intersystem crossing(ISC) dynamics into the lowest-energy triplet state. The long-livedand reactive triplet states of sulfur-substituted nucleobases arecrucial due to their wide range of potential applications in medicine,structural biology, and the development of organic light-emittingdiodes (OLEDs) and other emerging technologies. However, a comprehensiveunderstanding of non-negligible wavelength-dependent changes in theinternal conversion (IC) and ISC events is still lacking. Here, westudy the underlying mechanism using joint experimental gas-phasetime-resolved photoelectron spectroscopy (TRPES) and theoretical quantumchemistry methods. We combine 2,4-dithiouracil (2,4-DTU) TRPES experimentaldata with computational analysis of the different photodecay processes,which are induced by increasing excitation energies along the entirelinear absorption (LA) ultraviolet (UV) spectrum. Our results showhow the double-thionated uracil (U), i.e., 2,4-DTU, appears as a versatilephotoactivatable instrument. Multiple decay processes can be initiatedwith different ISC rates or triplet-state lifetimes that resemblethe distinctive behavior of the singly substituted 2- or 4-thiouracil(2-TU or 4-TU). We obtained a clear partition of the LA spectrum basedon the dominant photoinduced process. Our work clarifies the reasonsbehind the wavelength-dependent changes in the IC, ISC, and triplet-statelifetimes in doubly thionated U, becoming a biological system of utmostimportance for wavelength-controlled applications. These mechanisticdetails and photoproperties are transferable to closely related molecularsystems such as thionated thymines

Polymerization-dependent activation of porcine γδ T-cells by proanthocyanidins

Plant-derived proanthocyanidins (PAC) have been promoted as a natural method of improving health and immune function in livestock. It has previously been shown that PAC are effective agonists for activating ruminant γδ T-cells in vitro, however effects on other livestock species are not yet clear. Moreover, the fine structural characteristics of the PAC which contribute to this stimulatory effect have not been elucidated. Here, we demonstrate activation of porcine γδ T-cells by PAC via up-regulation of CD25 (IL-2Rα) and show that 1) activation is dependent on degree of polymerization (DP), with PAC fractions containing polymers with mean DP >6 significantly more effective than fractions with mean DP <6, whilst flavan-3-ol monomers (the constituent monomeric units of PAC) did not induce CD25 expression and 2) both procyanidin and prodelphinidin-type PAC are effective agonists. Furthermore, we show that this effect of PAC is restricted to the γδ T-cell population within porcine peripheral mononuclear cells as significant CD25 up-regulation was not observed in non γδ T-cells, and no activation (via CD80/86 up-regulation) was evident in monocytes. Our results show that dietary PAC may contribute to enhancement of innate immunity in swine via activation of γδ T-cells

The Role of the Toll-like Receptor 2 and the cGAS-STING Pathways in Breast Cancer: Friends or Foes?

: Breast cancer stands as a primary malignancy among women, ranking second in global cancer-related deaths. Despite treatment advancements, many patients progress to metastatic stages, posing a significant therapeutic challenge. Current therapies primarily target cancer cells, overlooking their intricate interactions with the tumor microenvironment (TME) that fuel progression and treatment resistance. Dysregulated innate immunity in breast cancer triggers chronic inflammation, fostering cancer development and therapy resistance. Innate immune pattern recognition receptors (PRRs) have emerged as crucial regulators of the immune response as well as of several immune-mediated or cancer cell-intrinsic mechanisms that either inhibit or promote tumor progression. In particular, several studies showed that the Toll-like receptor 2 (TLR2) and the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathways play a central role in breast cancer progression. In this review, we present a comprehensive overview of the role of TLR2 and STING in breast cancer, and we explore the potential to target these PRRs for drug development. This information will significantly impact the scientific discussion on the use of PRR agonists or inhibitors in cancer therapy, opening up new and promising avenues for breast cancer treatment

Cyberknife Radiosurgery for Trigeminal Neuralgia

IntroductionImage-guided robotic radiosurgery is an emerging minimally-invasive treatment option for trigeminal neuralgia (TN). Our group has treated 560 cases up to date, and report here the clinical outcomes of 387 treatments with three years follow-up. This study represents the largest single-center experience on CyberKnife radiosurgery for the treatment of TN so far reported.MethodsCyberKnife radiosurgery treatment was offered to patients with drug-resistant TN, after the failure of other treatments or refusal of invasive procedures. A second treatment was offered to patients with a poor response after the first treatment or with recurrent pain. Treatment protocol required the non-isocentric delivery of 60 Gy prescribed to the 80% isodose to a 6 mm retrogasserian segment of the affected trigeminal nerve. Retreatments typically received 45 Gy, again prescribed to the 80% isodose. The final plan was developed accordingly to individual anatomy and dose distribution over the trigeminal nerve, gasserian ganglion, and brainstem. Clinical outcomes such as pain control and hypoesthesia/numbness have been evaluated after 6, 12, 24, and 36 months.ResultsOur group has treated 527 patients with Cyberknife radiosurgery at Centro Diagnostico Italiano (CDI), Milan, Italy, during the last decade. A minimum follow-up of six months was available on 496 patients. These patients received 560 treatments: 435 patients (87.7%) had a single treatment, 60 patients (12.1%) had two treatments, and one patient (0.2%) had five treatments (two on the right side, three on the left side). Twenty four patients had multiple sclerosis (4.8%). Four hundred and forty-three patients (84%) received the treatment without previous procedures, while 84 patients (16%) underwent radiosurgery after the failure of other treatments. A neurovascular conflict was identified in 59% of the patients. Three hundred and forty-three patients (receiving a total of 387 treatments) had a minimum of 36 months follow up. Pain relief rate at 6, 12, 18, 24, 30 and 36 months was respectively 92, 87, 87, 82, 78 and 76%. Forty-four patients out of 343 (12.8%) required a second treatment during the observed period. At 36 months post-treatment, 21 patients (6,1%) reported the presence of bothering facial hypoesthesia. Eighteen patients out of 21 (85.7%) developed this complication after a repeated treatment.ConclusionsFrameless image-guided robotic radiosurgery in experienced hands is a safe and effective procedure for the treatment of TN, providing excellent pain control rates in the absence of major neurological complications. Repeated treatments due to recurrent pain are associated with restored pain control but at the price of a higher rate of sensory complications

Abnormal NK cell lymphocytosis detected after splenectomy: association with repeated infections, relapsing neutropenia, and persistent polyclonal B-cell proliferation

Abnormal NK cell lymphocytosis detected after splenectomy: association with repeated infections, relapsing neutropenia, and persistent polyclonal B-cell proliferation. Granjo E, Lima M, Fraga M, Santos F, Magalhães C, Queirós ML, Moreira I, Rocha S, Silva AS, Rebelo I, Quintanilha A, Ribeiro ML, Candeias J, Orfão A. Department of Hematology, Hospital S. João, Porto, Portugal. [email protected] Abstract We report the case of a boy with hereditary spherocytosis who presented with mild microcytic hypochromic anemia and recurrent leg ulcers that had been present since childhood. Chronic natural killer (NK) cell and B-cell lymphocytosis was detected 1 year after therapeutic splenectomy during investigation of recurrent episodes of neutropenia and persistent lymphocytosis. NK cells proved to be abnormal at immunophenotyping studies, and B-cells were polyclonal and displayed a normal immunophenotype. Genotypic analysis of T-cell receptor (TCR)-beta and TCR-gamma genes showed a germ-line pattern. The clinical course of this patient was characterized by multiple pulmonary infections and amygdalitis. We discuss the potential roles of persistent immune stimulation due to chronic hemolysis and severe leg ulcers and of splenectomy in the origin of NK cell lymphocytosis and the relationship between NK cells and recurrent infections, relapsing neutropenia, and polyclonal B-cell response