206 research outputs found

    Flower roundabouts and double-lane roundabouts: a comparative performance analysis

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    AbstractIn the paper, a choice criterion between flower roundabouts and double-lane roundabouts is proposed, focusing on operational benefits that can derive from one scheme over the other, and outlining a general framework for benefit-cost analysis. In order to assess operational benefits of innovative roundabouts over modern roundabouts, a comparative analysis was made. Capacity was estimated using gap-acceptance models. In detail, assuming the dichotomic shifted negative exponential distribution to model headways in circulating streams, the Hagring formula was adjusted to obtain entry capacity estimations at roundabout approaches where entering vehicles face one or two conflicting flows. Based on the control delay, the suitability domains and indifference areas were constructed. Thus, a sensitivity analysis to changes in traffic demand for operational benefits of flower roundabouts over double-lane roundabouts was carried out and discussed. At last, evidence for new installations and conversion of existing roundabouts can be found

    Fronto-Orbito-zygomatic approach: a technical modification.

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    The fronto-orbito zygomatic approach is part of the surgical armamentarium of modern skull base surgery. As described in the literature, it requires costly technological tools such as powerful drills and saws, to be performed. In the present communication we describe a technical modification that allows the zygoma to be elevated "en bloc" together with the fronto-orbital bone flap by means of appropriate use of the Gigli's saw. Using this technique, adequate replacement of the craniotomy flap requires only two silk sutures. This technical modification, which was already successfully used in over 20 cases, would also allow this useful approach to be performed in those neurosurgical environments where modern costly technology for cranial base surgery is not available

    Nitrosative stress defences of the enterohepatic pathogenic bacterium Helicobacter pullorum

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    Helicobacter pullorum is an avian bacterium that causes gastroenteritis, intestinal bowel and hepatobiliary diseases in humans. Although H. pullorum has been shown to activate the mammalian innate immunity with release of nitric oxide (NO), the proteins that afford protection against NO and reactive nitrogen species (RNS) remain unknown. Here several protein candidates of H. pullorum, namely a truncated (TrHb) and a single domain haemoglobin (SdHb), and three peroxiredoxin-like proteins (Prx1, Prx2 and Prx3) were investigated. We report that the two haemoglobin genes are induced by RNS, and that SdHb confers resistance to nitrosative stress both in vitro and in macrophages. For peroxiredoxins, the prx2 and prx3 expression is enhanced by peroxynitrite and hydrogen peroxide, respectively. Mutation of prx1 does not alter the resistance to these stresses, while the single ∆prx2 and double ∆prx1∆prx2 mutants have decreased viability. To corroborate the physiological data, the biochemical analysis of the five recombinant enzymes was done, namely by stopped-flow spectrophotometry. It is shown that H. pullorum SdHb reacts with NO much more quickly than TrHb, and that the three Prxs react promptly with peroxynitrite, Prx3 displaying the highest reactivity. Altogether, the results unveil SdHb and Prx3 as major protective systems of H. pullorum against nitrosative stress

    Predictors of Hepatocellular Carcinoma Early Recurrence in Patients Treated with Surgical Resection or Ablation Treatment: A Single-Center Experience

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    Introduction: Hepatocellular carcinoma (HCC) is the sixth most diagnosed malignancy and the fourth leading cause of cancer-related death worldwide, with poor overall survival despite available curative treatments. One of the most crucial factors influencing survival in HCC is recurrence. The current study aims to determine factors associated with early recurrence of HCC in patients with BCLC Stage 0 or Stage A treated with surgical resection or local ablation. Materials and Methods: We retrospectively enrolled 58 consecutive patients diagnosed with HCC within BCLC Stage 0 or Stage A and treated either by surgical resection or local ablation with maximum nodule diameter 20 mm (HR 4.5, 95% C.I. 3.9–5.1), platelet count 2 (HR 2.7, 95% C.I. 2.2–3.3). Discussion and Conclusions: Our results are in line with the current literature. Male gender and tumor nodule dimension are the main risk factors associated with early HCC recurrence. Platelet count and other combined scores can be used as predictive tools for early HCC recurrence, although more studies are needed to define cut-offs

    Giacomo Serpotta e il "pareggiamento delle arti": la decorazione degli oratori fra manipolazione vitalistica e vocazione classicista

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    ABSTRACT GIACOMO SERPOTTA AND THE “EQUALIZATION OF THE ARTS”: DECORATION OF THE ORATORIES BETWEEN VITALISTIC MANIPULATION AND CLASSICIST VOCATION Ettore Sessa The value of the whole of Giacomo Serpotta's artistic vision in the orchestration of the figu¬rative apparatuses of his oratories was certainly one of the principal primers of his historical-critical raising in the modernist period. In 1901 Mauceri and in 1911 Ricci and Basile heighten a profile of it, however synthetic, of angling and above all of different breath from the rediscovery realized in positivist age. Classifiable, in fact, among the eighteenth century precedents of Gesamtkunstwerk aesthetical plant (according to a rather diffused custom within the artistic historiography of modernist culturaI area or of decadentist origin, as in different formalistic demonstrations of the wealthiest society Belle Époque) the progress of Serpottas artistic way towards tangible expressions of the idea of «the whole work of art» has a unmistakable im¬print of his and, at the same time, a feasibility thanks to the plasticism of gestures and to the uni¬tary multiplicity of his modeled. In his oratories arrangements the "realist" component, not exempted from hedonistic sensual witty remarks, acts on a foundation of Hellenic taste (also in the use of profiles and architectural elements). With wise modulation and with dosing diversified for intensity, according the nature of the subjects, combines history (see the «teatrini» with perspective sceneries, among which the Lepanto battle), micro history (from feminine allegorical subjects, to attractive dames modernly adorned with ends and brocades, to "picciotti" proudly ragged and to the anecdotal of the daily life), mysticism (from the devotional subjects to the allegories of the virtues), obscurity (from numerological components to philosophical attributes) and, finally, mythology (from the allegorical correspondences between Christianity and paganism to classical simbology). Despite the actual halving of this group of oratories (was destroyed by traumatic events as earthquakes and war actions, or by villainous demolitions big part of Serpottas works, among which the SS. Sacrament oratories to Kalsa and those of Saint Maria del Ponticello), the comparison among the palermitan examples reached us entire allows the individualization of the characters of originality typical of the generaI composition, over that of those figurative unanimously accredited among the most valid of the late- Baroque European sculpture. The typical scheme of these oratories, places with a strong secular imprint (predisposed as for cultural reunions how as for the preclusive congregational assemblies, to which the only ones not admitted affiliate were the artists), has as constants: the hall with a rectangular plant; the skiff or pavilion vault with plaster decorations dissimulating the constructive geometry; the sculptural wall register above of a high plinth; windows on the greatest sides (in number of three); two doors in the counterfacade, originally with desk for the assemblies in central position, below the principal devotional allegorical composition. The first oratory to which Giacomo Serpotta imposes an unitary imprint, except the cappellone only defined between 1717 and the following year) is that of SS. Rosary in S. Cita; he has worked since 1685 to 1688 on behalf of SS. Rosary Company. Serpotta is twenty nine, but already since almost ten years, after the apprenticeship with subordinate roles, he showed himself almost beginning in mute with the decorations of Madonna of the Pity church in Monreale, where he operated like Procopio De' Ferrari's collaborator, and perhaps with his interventions in 1678 in the lateral walls of S. Mercurio oratory, to which follow the 1679 decoration works in the Charity oratory in St. Bartholomeo of the Incurable people (no more existing), perhaps S. Pietro and S. Paolo statues dating back to 1680 for the greatest altar in Gancia church, the marble model for Charles H's equestrian monument for Messina (then realized in 1684) and during the two years 1683-1684 the scenic decorations for the transept altars of Carmine Maggiore church (where he collaborates with his brother Giuseppe and realizes the couples of twisted columns gilded and commented by a theory of plaster miniature scenes disposed according to a spiral development). Immediately after S. Cita oratory he realized, between 1688 and 1691, the decorative apparatuses of the Sacrament oratory in S. Nicolò to Kalsa (destroyed because of 1823 earthquake). Only eight years after the completion of this work (about which it was hypothesized that it were an advancement in comparison to the intervention in S. Cita) Giacomo Serpotta is entrusted by S. Francesco from Assisi and S. Lorenzo Companies to realize the complex allegorical and explanatory cycle of the plasters of S. Lorenzo orato¬ry. He worked partly on Giacomo Amato's sketches (to which are probably owed the reform interventions that confer to this oratory a great architectural "squaring" in comparison to others), completing the presbytery within 1706, while already from 1701 he is busy in the definition of the walls. In 1703 he began the counter facade with the monumental wall framework and high-relief representation of St. Lorenzo Martyrdom

    The right to food and food diversity in the Italian Constitution

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    Il contributo analizza la tutela apprestata dalla Costituzione italiana al diritto al cibo che, pur non essendo espressamente menzionato, viene ricavato attraverso l'analisi di principi ed azioni sottese alla nostra Carta che ne riconoscono il valore: il principio lavorista, la lotta alla povertà, la retribuzione del lavoratore...

    Microsecond Time-Resolved Absorption Spectroscopy Used to Study CO Compounds of Cytochrome bd from Escherichia coli

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    Cytochrome bd is a tri-heme (b558, b595, d) respiratory oxygen reductase that is found in many bacteria including pathogenic species. It couples the electron transfer from quinol to O2 with generation of an electrochemical proton gradient. We examined photolysis and subsequent recombination of CO with isolated cytochrome bd from Escherichia coli in oneelectron reduced (MV) and fully reduced (R) states by microsecond time-resolved absorption spectroscopy at 532-nm excitation. Both Soret and visible band regions were examined. CO photodissociation from MV enzyme possibly causes fast (t,1.5 ms) electron transfer from heme d to heme b595 in a small fraction of the protein, not reported earlier. Then the electron migrates to heme b558 (t,16 ms). It returns from the b-hemes to heme d with t,180 ms. Unlike cytochrome bd in the R state, in MV enzyme the apparent contribution of absorbance changes associated with CO dissociation from heme d is small, if any. Photodissociation of CO from heme d in MV enzyme is suggested to be accompanied by the binding of an internal ligand (L) at the opposite side of the heme. CO recombines with heme d (t,16 ms) yielding a transient hexacoordinate state (CO-Fe2+ -L). Then the ligand slowly (t,30 ms) dissociates from heme d. Recombination of CO with a reduced heme b in a fraction of the MV sample may also contribute to the 30-ms phase. In R enzyme, CO recombines to heme d (t,20 ms), some heme b558 (t,0.2–3 ms), and finally migrates from heme d to heme b595 (t,24 ms) in ,5% of the enzyme population. Data are consistent with the recent nanosecond study of Rappaport et al. conducted on the membranes at 640-nm excitation but limited to the Soret band. The additional phases were revealed due to differences in excitation and other experimental conditions
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