131 research outputs found

    La societĂ  dell'algoritmo e l'eclissi della problematicitĂ 

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    Gli strumenti tecnici di cui l’uomo dispone tendono a trasformare la natura stessa dell’umano. La ‘rivoluzione digitale’ amplifica la potenza della tecnica. Il primato della funzionalità operativa completa la trasformazione dei mezzi in fini. L’insieme dei mezzi informatici e la ragione algoritmica che le società avanzate sono riuscite a ideare e utilizzare è diventato lo scopo esistenziale fondamentale di tali società con conseguenze cognitive, percettive, immaginative e affettive inedite e dagli esiti ancora largamente sconosciuti.The technical tools available to man tend to transform the very nature of the human being. The ‘digital revolution’ amplifies the power of technology. The primacy of operational functionality completes the transformation of means into ends. The whole of IT instruments and algorithmic rationality that the most scientifically advanced societies managed to conceive and employ has become the fundamental existential purpose of these societies, bearing cognitive, perceptual, imaginative, and affective consequences, which are largely unknown at present

    L'anti-dantismo politico di Machiavelli. Riflessioni critiche e meta-critiche.

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    Il saggio mette in risalto i limiti dell’anti-dantismo politico di Machiavelli. La storia del rapporto che il Segretario fiorentino ha intrattenuto con Dante è la storia di una passione ambivalente, non di un atteggiamento lineare, vigile e disincantato. Alla luce della filosofia della vita di Machiavelli, la critica di quest’ultimo nei confronti del Dante politico si riduce ad una crepuscolare e idealizzante auto-elevazione come civis florentinus.The essay highlights the limits of Machiavelli's political criticism of Dante. The story of the relationship between the former and the latter is the story of an ambivalent passion, not of a linear, self-aware and disenchanted attitude. In light of Machiavelli's philosophy of life, the latter's criticism of Dante’s political position can be seen as a crepuscular and idealizing self-elevation as civis florentinus

    Theft and Entertainment

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    An anthology that looks at the interaction between theft and entertainment. Why and how entertainment is stolen, the prevention of theft by entertainment companies, and the depiction of theft in media

    Optical spectra of molecular aggregates and crystals: testing approximation schemes

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    The interplay between exciton delocalization and molecular vibrations profoundly affects optical spectra of molecular aggregates and crystals. The exciton motion occurs on a similar timescale as molecular vibrations, leading to a complex and intrinsically non-adiabatic problem that has been handled over the years introducing several approximation schemes. Here we discuss systems where intermolecular distances are large enough so that only electrostatic intermolecular interactions enter into play and can be treated in the dipolar approximation. Moreover, we only account for interactions between transition dipole moments, as relevant to symmetric molecules, with negligible permanent (multi)polar moments in the ground and low-lying excited states. Translational symmetry is fully exploited to obtain numerically exact solutions of the relevant Hamiltonian for systems of comparatively large size. This offers a unique opportunity to assess the reliability of different approximation schemes. The so-called Heitler–London approximation, only accounting for the effects of intermolecular interactions among degenerate electronic states, leads to the celebrated exciton model, widely adopted to describe optical spectra of molecular aggregates and crystals. We demonstrate that, mainly due to a cancellation of errors, the exciton model approximates well the position of exciton bands and reasonably well the bandshapes, but it fails to predict spectral intensities, leading to underestimated intensities in J-aggregates and overestimated intensities in H-aggregates. This general result is validated against an exact sum-rule. Finally, we address the validity of several approximation schemes adopted to reduce the dimension of the vibrational basis

    Ecological sustainability of aquafeed: an emergy assessment of novel or underexploited ingredients

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    Fishmeal is the optimal source of protein for fed fish and crustacean species, but the increase in market demand and prices is pushing the aquaculture industry to test alternative protein sources. This paper provides the results of an emergy assessment performed on four partial substitutes for fishmeal – dried microalgae biomass from Tetraselmis suecica and Tisochrysis lutea, insect meal from Hermetia illucens larvae, and poultry by-product meal – and then compares them with the findings of a previously published Life Cycle Assessment (LCA) on the same topic. By quantifying their degree of dependence on natural resources, the research offers a complementary perspective to that of LCA, thus allowing to obtain a complete picture on the sustainability of the four production systems. Firstly, the results reveal that insect meal has the highest environmental efficiency in terms of total emergy per unit of product, followed by poultry by-product meal. The two closed microalgae cultivation systems are penalized by a low productivity, combined with a high quantity of seawater imported. Secondly, several critical aspects are highlighted by the five emergy-based indicators: in brief, all systems appear to be based on intensive industrial processes, with the imported inputs from the economy representing 99% of total emergy flow (high level of ecosystem stress). Since local renewable inputs are not significantly exploited, higher levels of production amplify the ratio between these resources and the inputs imported from the outer economies (no economies of scale are observed). Finally, the comparison with LCA results confirms a critical point already detected by the emergy assessment (i.e. the crucial contribution of the feed provided to insect and poultry) but also reveals new ones: (i) in the two microalgae systems, the high emergy contribution from seawater versus the high impacts of carbon dioxide and energy needs; (ii) in the insect meal system, the high emergy share represented by human labour and energy needs. In light of the numerous problems found, possible approaches are proposed to increase the environmental performance through changes to each production system and the processes that support it upstream

    Optical and Near-IR Imaging of the Dark Globule CB 52

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    The internal structure of the dark globule CB 52 is investigated by means of broadband imaging in the optical and near-IR spectral range. By exploiting the extinction of the stellar light within this object, we derive observational parameters suitable to infer the internal structure of this cloud. Extinction maps were obtained at different wavelengths by using both stellar counts and two-color diagrams. While in the optical region the extinction is better evaluated at the cloud boundaries, the internal regions are more conveniently probed in the near-IR, so a combined map was derived. The total-to-selective extinction ratio RV was also observed to increase toward the inner regions, and a plot versus the extinction AV suggests that grain growth processes are active in this cloud. The statistical fluctuation of the AV, estimated in the line of sight of the background stars, is investigated by comparing the observed stellar colors with those of the unreddened stars. The dispersion σAV, derived from optical observations, is found to be almost independent of the mean extinction, AV, while by using near-IR data we find a more complex behavior: the σAV versus AV relation increases until AV ~ 6 and then decreases for larger extinctions. This is discussed in the framework of a simple model, suggesting that a clumpy and clustered structure can explain the observations in the inner regions, while outside the cloud the mass distribution remains more homogeneous

    The Structure of the Small Dark Cloud CB 107

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    This paper presents the near-IR imaging observations of CB 107, a small dark globule projected against a rich stellar background. By means of accurate photometry, the near-IR two-color diagram J - H versus H - K was obtained for the stellar background. This information was used to estimate the color excesses of the detected stars so that, given the reddening curve, it was possible to derive the extinction map of the cloud. The structural properties of the dark globule were investigated by plotting the extinction dispersion σ, obtained in a given spatial box, as a function of the mean extinction AV. This relationship has shown quite a definite linear behavior, with the slope increasing with the box size. The results of the present analysis, compared with those obtained by other authors on larger dark clouds, suggest that for a given spatial scale the slope of the σ versus AV relation is greater in CB 107 than in larger clouds. The so-called Δ-variance method was also used to investigate the structure of the dark globule by evaluating the drift behavior of its extinction map. In this way, we have found that the power spectrum of the extinction map is characterized by a power law with exponent β ~ 2.7. This value is lower than expected, for the same range of spatial scales, on the basis of previous work on large molecular clouds

    Antiadiabatic View of Fast Environmental Effects on Optical Spectra

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    An antiadiabatic approach is proposed to model how the refractive index of the surrounding medium affects optical spectra of molecular systems in condensed phases. The approach solves some of the issues affecting current implementations of continuum solvation models and more generally of effective models where a classical description is adopted for the molecular environment

    Hematopoiesis and immune reconstitution after CD19 directed chimeric antigen receptor T‐cells (CAR‐T): A comprehensive review on incidence, risk factors and current management

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    Impaired function of hematopoiesis after treatment with chimeric antigen T-cells (CAR-T) is a frequent finding and can interest a wide range of patients, regardless of age and underlying disease. Trilinear cytopenias, as well as hypogammaglobulinemia, B-cell aplasia, and T-cell impairment, can severely affect the infectious risk of CAR-T recipients, as well as their quality of life. In this review, we provide an overview of defects in hematopoiesis after CAR-T, starting with a summary of different definitions and thresholds. We then move to summarize the main pathogenetic mechanisms of cytopenias, and we offer insight into cytomorphological aspects, the role of clonal hematopoiesis, and the risk of secondary myeloid malignancies. Subsequently, we expose the major findings and reports on T-cell and B-cell quantitative and functional impairment after CAR-T. Finally, we provide an overview of current recommendations and leading experiences regarding the management of cytopenias and defective B- and T-cell function

    Venous Thromboembolism in Lymphoma: Risk Stratification and Antithrombotic Prophylaxis

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    Lymphoma is listed among the neoplasias with a high risk of venous thromboembolism (VTE). Risk factors for VTE appear to differ from risk factors in solid tumors. We review the literature of the last 20 years for reports identifying these risk factors in cohorts consisting exclusively of lymphoma patients. We selected 25 publications. The most frequent studies were analyses of retrospective single-center cohorts. We also included two reports of pooled analyses of clinical trials, two meta-analyses, two analyses of patient registries, and three analyses of population-based databases. The VTE risk is the highest upfront during the first two months after lymphoma diagnosis and decreases over time. This upfront risk may be related to tumor burden and the start of chemotherapy as contributing factors. Factors consistently reported as VTE risk factors are aggressive histology, a performance status ECOG 65 2 leading to increased immobility, more extensive disease, and localization to particular sites, such as central nervous system (CNS) and mediastinal mass. Association between laboratory values that are part of risk assessment models in solid tumors and VTE risk in lymphomas are very inconsistent. Recently, VTE risk scores for lymphoma were developed that need further validation, before they can be used for risk stratification and primary prophylaxis. Knowledge of VTE risk factors in lymphomas may help in the evaluation of the individual risk-benefit ratio of prophylaxis and help to design prospective studies on primary prophylaxis in lymphoma
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