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Frequency resolved optical gating is the core method for characterising ultra-fast optical pulses. Here, the authors use zero-index nonlinearities to largely enhance key performances and enable simultaneous second and third harmonic measurements.

BackgroundElevated plantar pressures represent a significant risk factor for neuropathic diabetic foot (NDF) ulceration. Foot offloading, through custom-made insoles, is essential for prevention and healing of NDF ulcerations. Objective quantitative evaluation to design custom-made insoles is not a standard method. Aims: 1) to develop a novel quantitative-statistical framework (QSF) for the evaluation and design of the insoles' offloading performance through in-shoe pressure measurement; 2) to compare the pressure-relieving efficiency of traditional shape-based total contact customised insoles (TCCI) with a novel CAD-CAM approach by the QSF.MethodsWe recruited 30 neuropathic diabetic patients in cross-sectional study design. The risk-regions of interest (R-ROIs) and their areas with in-shoe peak pressure statistically ≥200kPa were identified for each patients' foot as determined on the average of peak pressure maps ascertained per each stance phase. Repeated measures Friedman test compared R-ROIs' areas in three different walking condition: flat insole (FI); TCCI and CAD-CAM insoles.ResultsAs compared with FI (20.6±12.9 cm2), both the TCCI (7±8.7 cm2) and the CAD-CAM (5.5±7.3 cm2) approaches provided a reduction of R-ROIs mean areas (pConclusionsThe CAD-CAM strategy achieves better offloading performance than the traditional shape-only based approach. The introduced QSF provides a more rigorous method to the direct 200kPa cut-off approach outlined in the literature. It provides a statistically sound methodology to evaluate the offloading insoles design and subsequent monitoring steps. QSF allows the analysis of the whole foot's plantar surface, independently from a predetermined anatomical identification/masking. QSF can provide a detailed description about how and where custom-made insole redistributes the underfoot pressure respect to the FI. Thus, its usefulness extends to the design step, helping to guide the modifications necessary to achieve optimal offloading insole performances.

Infrared femtosecond laser pulses are important tools both in strong-field physics, driving x-ray high-harmonic generation, and as the basis for widely tunable, if inefficient, ultrafast sources in the visible and ultraviolet. Although anomalous material dispersion simplifies compression to few-cycle pulses, attosecond pulses in the infrared have remained out of reach. We demonstrate soliton self-compression of 1800-nm laser pulses in hollow capillary fibers to subcycle envelope duration (2 fs) with 27-GW peak power, corresponding to attosecond field transients. In the same system, we generate wavelength-tunable few-femtosecond pulses from the ultraviolet (300 nm) to the infrared (740 nm) with energy up to 25μJ and efficiency up to 12%, and experimentally characterize the generation dynamics in the time-frequency domain. A compact second stage generates multi-microjoule pulses from 210 to 700 nm using less than 200μJ of input energy. Our results significantly expand the toolkit available to ultrafast science.

The formation of congestion on an urban road network is a key issue for the development of sustainable mobility in future smart cities. In this work, we propose a reductionist approach by studying the stationary states of a simple transport model using a random process on a graph, where each node represents a location and the link weights give the transition rates to move from one node to another, representing the mobility demand. Each node has a maximum flow rate and a maximum load capacity, and we assume that the average incoming flow equals the outgoing flow. In the approximation of the single-step process, we are able to analytically characterize the traffic load distribution on the single nodes using a local maximum entropy principle. Our results explain how congested nodes emerge as the total traffic load increases, analogous to a percolation transition where the appearance of a congested node is an independent random event. However, using numerical simulations, we show that in the more realistic case of synchronous dynamics for the nodes, entropic forces introduce correlations among the node states and favor the clustering of empty and congested nodes. Our aim is to highlight the universal properties of congestion formation and, in particular, to understand the role of traffic load fluctuations as a possible precursor of congestion in a transport network.

Abstract Adopting quantum resources for parameter estimation discloses the possibility to realize quantum sensors operating at a sensitivity beyond the standard quantum limit. Such an approach promises to reach the fundamental Heisenberg scaling as a function of the employed resources N in the estimation process. Although previous experiments demonstrated precision scaling approaching Heisenberg-limited performances, reaching such a regime for a wide range of N remains hard to accomplish. Here, we show a method that suitably allocates the available resources permitting them to reach the same power law of Heisenberg scaling without any prior information on the parameter. We demonstrate experimentally such an advantage in measuring a rotation angle. We quantitatively verify sub-standard quantum limit performances for a considerable range of N (O(30,000)) by using single-photon states with high-order orbital angular momentum, achieving an error reduction, in terms of the obtained variance, >10 dB below the standard quantum limit. Such results can be applied to different scenarios, opening the way to the optimization of resources in quantum sensing.

BackgroundBempedoic acid (BA) is a small-molecule first-in-class of inhibitor of ATP citrate lyase that significantly lowers low-density lipoproteins cholesterol (LDL-c) in statin-intolerant and inadequate responders. Increased serum uric acid (SUA) levels and gout incidence have been described in BA-treated patients. The aim of this systematic review was to investigate the safety of BA regarding SUA levels and gout in randomised controlled trials (RCTs).MethodsA search on 7 databases was performed from inception to May 4, 2023. RCTs of BA monotherapy or combination with other lipid-lowering treatment (LLT) in patients with increased LDL-c were included. Dual data extraction was performed with disagreements resolved through consensus. Due to the methodological purpose of this review risk-of-bias assessment of studies was not performed.Results6 Phase 3 RCTs (N = 17,975 patients of which 9,635 received BA) 9 Phase 2 RCTs (N = 362 patients of which 170 received BA) and an open-label extension of a Phase 3 RCT were included. Gout and/or hyperuricemia were not mentioned as exclusion criteria, previous/current use of urate-lowering therapies (ULT) and/or colchicine and/or dietary patterns were not reported. Phase 3 RCTs: 2 studies specified the number of patients experiencing hyperuricemia over the study period (BA: 4.9%–11%; placebo: 1.9%–5.6%) and the effect size was significant only in 1 study (OR = 2.0, 95% CI 1.8–2.3). Four RCTs reported a higher incidence of gout in the BA arm however, when we calculated the effect size, it was small and often not significant. Two studies reported 0 cases of gout. The paucity of information about SUA levels at baseline and/or at the end of follow-up do not allow us to quantify the effect sizes for BA-induced SUA elevation. Data on gout from Phase 2 RCTs is scant.ConclusionsData from phase 2 and 3 RCTs do not allow for confirming a clear association between BA and gout. It is conceivable that a careful assessment of SUA levels/history of gout at baseline and the concomitant use of urate-lowering agents may be instrumental to minimise the risk of new-onset gout/gout flares in patients treated with BA.

This short essay is focused on Dante’s influence on Pier Paolo Pasolini’s work. Obviously, it does not claim to complete this theme. It tries to explain some research hypothesis which constitute the theoretical foundation for A Divine Comedy: Dante/Pasolini, a theatrical performance directed in 2019 by Antonio Latella in Munich. The show was selected by Berliner Theatertreffen as one of the best ten production for the year 2020.

In this essay I reflect on the role mathematics plays in Melville’s works and imagination moving from one specific mathematical reference in chapter XCVI of Moby-Dick “The Try-Works.” Here Ishmael mentions the cycloid, a peculiar geometrical construct that was at the center of mathematical and philosophical debates during the 17th century. In the first part of my essay I intend to show how it is only in the light of some of its properties that Ishmael’s playful reference to the cycloid can be understood, thus testifying to the author’s profound understanding of these mathematical notions. Moreover, Melville must have also been aware of the pivotal role the cycloid played in the history of early modern thought: the investigation into its properties was at the basis of the invention of calculus, which in turn was at the center of the philosophy of post-Cartesian thinkers such as Leibniz and Spinoza. Building on this, in the second part of my essay I intend to show how Ishmael’s mention of the cycloid can be seen as a reference to a philosophical worldview according to which nature appears as a continuum of indefinitely foldable matter, a view in which Melville conflates such diverse thinkers as Spinoza, Plato, Goethe or the Transcendentalists and which he presents as both fascinating and problematic. Once the cycloid episode is read in this light and put in relation to a series of structurally similar scenes throughout the novel, it can be interpreted as the representation of this ambivalent position, one of many instances of Melville’s ability to bring together and keep alternative worldviews in creative tension.

In this paper we address a special case of ‘sloppy’ quantum estimation procedures which happens in the presence of intertwined parameters. A collection of parameters are said to be intertwined when their imprinting on the quantum probe that mediates the estimation procedure, is performed by a set of linearly dependent generators. Under this circumstance the individual values of the parameters can not be recovered unless one tampers with the encoding process itself. An example is presented by studying the estimation of the relative time-delays that accumulate along two parallel optical transmission lines. In this case we show that the parameters can be effectively untwined by inserting a sequence of balanced beam splitters (and eventually adding an extra phase shift on one of the lines) that couples the two lines at regular intervals in a setup that remind us a generalized Hong-Ou-Mandel interferometer. For the case of two time delays we prove that, when the employed probe is the frequency-correlated biphoton state, the untwining occurs in correspondence of exclusive zero-coincidence (EZC) point. Furthermore we show the statistical independence of two time delays and the optimality of the quantum Fisher information at the EZC point. Finally we prove the compatibility of this scheme by checking the weak commutativity condition associated with the symmetric logarithmic derivative operators.

In this paper we introduce a measure of genuine quantum incompatibility in the estimation task of multiple parameters, that has a geometric character and is backed by a clear operational interpretation. This measure is then applied to some simple systems in order to track the effect of a local depolarizing noise on the incompatibility of the estimation task. A semidefinite program is described and used to numerically compute the figure of merit when the analytical tools are not sufficient, among these we include an upper bound computable from the symmetric logarithmic derivatives only. Finally we discuss how to obtain compatible models for a general unitary encoding on a finite-dimensional probe.

Abstract – Samuel Beckett's interest in St. Augustine is manifest throughout his oeuvre, both in terms of content and style, and can be traced from his very first works, such as Whoroscope, to his last plays and short stories. Although this interplay has been touched upon in the critical discourse on Beckett, a systematic analysis is still to be done. This paper represents a preliminary investigation into the Augustinian influence in the early Beckett, in particular Dream of Fair to Middling Women and Murphy. By considering the presence of the Confessions in these two novels I intend to show how St. Augustine's work played a significant role in the development of the young author, offering him the occasion to overcome his theory of habit as outlined in his early essay, Proust. In this text, Beckett posits habit as merely “the generic name for the countless treaties concluded between the countless subjects that constitute the individual and their countless correlative objects”. Dream still endorses this perspective, but already suggests a different dialectic of memory, will, and habit. This shift, I argue, can be connected to Beckett’s reading of Augustine's meditations, in book VIII of the Confessions, on the cleavage between the spirit and the flesh. In Murphy, we see Beckett’s 'Augustinian dialectic' fully formed: habit is no longer a veil of Maya that hides the real essence of the individual, but the condition of possibility for the subject's flight from the “mercantile Gehenna” world towards the truth of the inner self.Riassunto – L'interesse di Samuel Beckett per Sant'Agostino è evidente nell'intero corpus dell'autore – a partire dai suoi primissimi lavori, in particolare la poesia Whoroscope, fino agli ultimi drammi e racconti – e si manifesta sia sul piano del contenuto che dello stile. Nonostante il rapporto tra i due autori sia già stato oggetto dell'attenzione dei critici, una sua analisi sistematica deve essere ancora compiuta. Nel presente saggio si offre una proposta di lettura della presenza agostiniana nel primo Beckett, in particolare Dream of Fair to Middling Women e Murphy. Considerando la presenza delle Confessioni in questi due romanzi intendo mostrare come i lavori di Sant'Agostino abbino giocato un ruolo fondamentale nello sviluppo del giovane autore, offrendogli l'occasione di superare la sua teoria dell'abitudine così come l'aveva rappresentata nel saggio giovanile Proust. In questo testo, Beckett descrive l'abitudine come “il nome generico per gli innumerevoli accordi stipulati fra gli innumerevoli soggetti che costituiscono l'individuo e i rispettivi innumerevoli oggetti”. In Dream si presenta la stessa prospettiva, ma già si intravedono i segni di una differente dialettica fra memoria, volontà e abitudine. Tale slittamento può essere ricondotto alla lettura delle meditazioni agostiniane nel libro VIII delle Confessioni, nelle quali si tematizza la scissione fra la volontà dello spirito e quella del corpo. In Murphy la dialettica agostiniana di Beckett giunge a compimento: l'abitudine non è più il velo di Maya che nascone l'essenza reale dell'individuo, ma la condizione di possibilità per la fuga del soggetto dalla “mercantile Gehenna” verso la verità dell'interiorità.

Relying on Max Weber’s and Colin Campbell’s description of the Spirit of Capitalism, I plan to interpret the narrators of Melville’s Bartleby and Cock-A-Doodle-Doo! as embodying two com­plementary aspects of the same ethical attitude informing such spirit. This is characterized by the oscillation between sentimentalism and individualism, charity and egoism, idealism and pragmatism, which Melville detected in the everyman of his time. In particular, I will focus on the references to the theological debate on free will and to the theme of melancholy as pivotal elements to comprehend Melville’s insight. Finally, I will show how Merrymusk and Bartleby, the two other main characters of the stories, may be seen as representing Melville’s attempt to question the American society of his time.

Il saggio tratta del significato della sedia a dondolo nel romanzo Murphy di Samuel Beckett, considerata come esempio della ‘simbologia geometrica’ dell’autore. Si sostiene che la forma della sedia a dondolo possa essere interpretata in relazione all’interesse di Beckett per i numeri irrazionali quali mezzo per illustrare il tipo di relazione fra i suoi personaggi e il mondo. Si propone inoltre di mettere in relazione in questo senso la sedia a dondolo con un altro oggetto tipicamente beckettiano, la bicicletta, che si rivela caratterizzata da una simbologia a essa complementare. La relazione fra questi due oggetti, si sostiene infine, può fungere da paradigma per una tipologia dei personaggi beckettiani, tesi fra una fuga verso un altrove indefinito e una fuga verso un’interiorità staccata dal mondo.

Habit plays an ambiguous role in Samuel Beckett's oeuvre: on the one hand, as he claims in his essay Proust, habit is merely considered as “the guarantee of a dull inviolability”, a protective screen dividing the subject from reality; on the other hand habit, as the area of friction between activity and passivity, is the object of extensive meditation and a pivotal element in the representation of Beckett's characters. In this paper I intend to investigate this ambiguity in the light of Félix Ravaisson's and Maine de Biran's philosophical reflection on the theme of habit and though a reading of the short story All Strange Away

In recent decades, a large number of audiovisual productions with a memoristic character have flooded Spanish television screens, highlighting the television obsession with the public evocation of the past of the political transition and the memory of some of its main political figures. This phenomenon makes up a vast corpus of television broadcasts whose marked memoristic character and prime-time broadcasting allows the establishment of an authentic television meta-narrative of wide diffusion and social projection in terms of the media construction of the public memory of the transition. Hence, the present article, in addition to mapping the genealogy of this television narrative, intends to delve into the knowledge of the public memory of the transition, as well as to reflect on the historical conditions of production and dissemination of such narratives and to analyze the formats, modes of representation and discursive mechanics.

The Stonemason (1995), Cormac McCarthy’s first published play, is a sustained meditation on the values of the ethic of craft as opposed to mere work, as well as on the difficult application of such values to reality. On the one hand, craft is represented as the quintessential value; on the other, it is measured against the real world in which values have to be constantly renegotiated in order to be useful. In this essay, I analyze how the tension between the ideal of the “craftsman hero,” represented by Papaw, and Ben’s attempt to live up to it traverses The Stonemason through three distinct if intertwined levels. First is the individual level, at which craft is intended as Ben’s personal experience of learning from Papaw how to lay stone upon stone as he struggles to hold his family together. Second is the social level: stonemasonry is one element of the economic system which is the battlefield for the struggle between the effort of the oppressed to improve their position and the ever-renewing ways in which the oppressors defend and exercise their power. Finally, there is the symbolic-mythical level: here stonemasonry is seen as the archetypical craft embodying a view of the world as the product of either a benevolent or an evil God. It is in the tension between the ideal and the reality of craftsmanship as it crosses these three dimensions that one can appreciate the full scope and complexity of McCarthy’s ethic of craft.