367 research outputs found

    Braided Bialgebras of Hecke-type

    Get PDF
    The paper is devoted to prove a version of Milnor-Moore Theorem for connected braided bialgebras that are infinitesimally cocommutative. Namely in characteristic different from 22, we prove that, for a given connected braided bialgebra (A,cA)(A,\mathfrak{c}_A) which is infinitesimally λ\lambda -cocommutative for some element λ≠0\lambda \neq 0 that is not a root of one in the base field, then the infinitesimal braiding of AA is of Hecke-type of mark λ\lambda and AA is isomorphic as a braided bialgebra to the symmetric algebra of the braided subspace of its primitive elements

    Weak Projections onto a Braided Hopf Algebra

    Get PDF
    We show that, under some mild conditions, a bialgebra in an abelian and coabelian braided monoidal category has a weak projection onto a formally smooth (as a coalgebra) sub-bialgebra with antipode; see Theorem 1.12. In the second part of the paper we prove that bialgebras with weak projections are cross product bialgebras; see Theorem 2.12. In the particular case when the bialgebra AA is cocommutative and a certain cocycle associated to the weak projection is trivial we prove that AA is a double cross product, or biproduct in Madjid's terminology. The last result is based on a universal property of double cross products which, by Theorem 2.15, works in braided monoidal categories. We also investigate the situation when the right action of the associated matched pair is trivial

    Cotensor Coalgebras in Monoidal Categories

    Full text link
    We introduce the concept of cotensor coalgebra for a given bicomodule over a coalgebra in an abelian monoidal category. Under some further conditions we show that such a cotensor coalgebra exists and satisfies a meaningful universal property. We prove that this coalgebra is formally smooth whenever the comodule is relative injective and the coalgebra itself is formally smooth

    Il consumo di suolo nella montagna lombarda. Un confronto tra piano e progetto urbano nel Novecento

    Get PDF
    Il testo confronta due forme di pianificazione che hanno governato lo sviluppo del territorio e regolato il consumo del suolo montano nel corso del Novecento: il progetto urbano degli anni Trenta-Quaranta e la pianificazione concordata degli anni Sessanta- Duemila. L’analisi si concentra sul caso di Sondalo in Alta Valtellina, un centro abitato d’impronta medievale dove, tra il 1932 e il 1940, fu costruito un Villaggio Sanatoriale di oltre 600.000 mc. Questo grandioso esempio di urbanistica modernista fu progettato per iniziativa statale nella forma di una megastruttura. Dopo la guerra, l’abitato di Sondalo è cresciuto grazie allo sviluppo economico e demografico propiziato dal grande sanatorio, secondo le indicazioni del Piano Regolatore e degli strumenti di pianificazione e programmazione sovralocali (PTCP, PTA). Gli autori propongono un confronto sugli esiti che queste due forme di urbanizzazione hanno prodotto sullo sviluppo territoriale e sul consumo di suolo in questo tratto di montagna lombarda

    Functional expression of TMEM16A in taste bud cells

    Get PDF
    Key points: Taste transduction occurs in taste buds in the tongue epithelium. The Ca2+-activated Cl– channels TMEM16A and TMEM16B play relevant physiological roles in several sensory systems. Here, we report that TMEM16A, but not TMEM16B, is expressed in the apical part of taste buds. Large Ca2+-activated Cl− currents blocked by Ani-9, a selective inhibitor of TMEM16A, are measured in type I taste cells but not in type II or III taste cells. ATP indirectly activates Ca2+-activated Cl– currents in type I cells through TMEM16A channels. These results indicate that TMEM16A is functional in type I taste cells and contribute to understanding the largely unknown physiological roles of these cells. Abstract: The Ca2+-activated Cl– channels TMEM16A and TMEM16B have relevant roles in many physiological processes including neuronal excitability and regulation of Cl– homeostasis. Here, we examined the presence of Ca2+-activated Cl– channels in taste cells of mouse vallate papillae by using immunohistochemistry and electrophysiological recordings. By using immunohistochemistry we showed that only TMEM16A, and not TMEM16B, was expressed in taste bud cells where it largely co-localized with the inwardly rectifying K+ channel KNCJ1 in the apical part of type I cells. By using whole-cell patch-clamp recordings in isolated cells from taste buds, we measured an average current of −1083 pA at −100 mV in 1.5 Î¼m Ca2+ and symmetrical Cl– in type I cells. Ion substitution experiments and blockage by Ani-9, a specific TMEM16A channel blocker, indicated that Ca2+ activated anionic currents through TMEM16A channels. We did not detect any Ca2+-activated Cl– currents in type II or III taste cells. ATP is released by type II cells in response to various tastants and reaches type I cells where it is hydrolysed by ecto-ATPases. Type I cells also express P2Y purinergic receptors and stimulation of type I cells with extracellular ATP produced large Ca2+-activated Cl− currents blocked by Ani-9, indicating a possible role of TMEM16A in ATP-mediated signalling. These results provide a definitive demonstration that TMEM16A-mediated currents are functional in type I taste cells and provide a foundation for future studies investigating physiological roles for these often-neglected taste cells

    Hygienic and dietetic guidelines for implant-supported full-arch immediate loading prostheses

    Get PDF
    Introduction: Proper oral hygiene and diet are important considerations for success in implant prosthodontics. However, detailed hygienic and dietetic guidelines for patients rehabilitated with implant-supported, immediate loading prostheses are lacking in the literature. Methods: The authors have developed a dietary and hygienic protocol for patients rehabilitated with implant-supported, full-arch, immediate loading prostheses in order to avoid occlusal overloads during osseointegration and optimize healing. Results: The dietary and hygienic guidelines provided in this paper emphasize the importance of maintaining proper oral hygiene and diet to support osseointegration and soft tissue healing during postsurgery healing periods. Conclusions: The protocol presented has been an effective instrument to obtain and maintain osseointegration in patients rehabilitated with full-arch, immediate loading prostheses

    Ergonomics and Workflow Evaluation of Automatic Doppler Angle Technology Implemented in a Diagnostic Ultrasound System

    Get PDF
    AbstractCommonly available Pulsed Wave Doppler (PW) flow velocity measurements for Ultrasound (US) investigation require the operator to manually set the direction of the flow velocity vector along the blood vessel axis on the US image, in order to determine the Doppler angle and then to estimate the real flow velocity. The present work investigates the possibility to implement on a commercially available US system an innovative Automatic Doppler Angle (ADA) Technology by analyzing the best workflow in terms of higher execution speed, lower keystrokes/adjustments helping in the prevention of Work-related Musculoskeletal Disorders (WRMSD) and a Doppler angle correction precision, comparable to the one obtained manually by expert sonographer. Ergonomics and workflow tests, then accuracy and repeatability evaluations of the Doppler velocity measurement, were performed on a portable US system (MyLabAlpha, Esaote S.p.A., Florence, Italy) by an expert sonographer. Ergonomics and workflow Tests were performed to analyze the potential of ADA in terms of reduction of muscular activation applied (by SEMG), number of activations (by cameras optoelectronic system) and time needed using ADA, in comparison to manual procedure. Accuracy and intra-operator repeatability tests of the velocity measurement were performed to evaluate the precision of the obtained PW trace velocity measurements with ADA technology, compared to manual ones. Results provided evidence that ADA tool allowed: a reduction of muscular activation (from 12% for trapezius descendens, to 25% for deltoideus anterior) a lower total number of keystrokes and a reduction of the US scan time of about 56%. The maximal variation between PW Doppler trace velocity measurement set automatically by ADA and set manually by sonographer was 11%. ADA technology can provide a Doppler angle correction precision comparable to the manual one, while decreasing the risk of WRMSD

    TMEM16A calcium-activated chloride currents in supporting cells of the mouse olfactory epithelium

    Get PDF
    Glial-like supporting (or sustentacular) cells are important constituents of the olfactory epithelium that are involved in several physiological processes such as production of endocannabinoids, insulin, and ATP and regulation of the ionic composition of the mucus layer that covers the apical surface of the olfactory epithelium. Supporting cells express metabotropic P2Y purinergic receptors that generate ATP-induced Ca2+ signaling through the activation of a PLC-mediated cascade. Recently, we reported that a subpopulation of supporting cells expresses also the Ca2+-activated Cl- channel TMEM16A. Here, we sought to extend our understanding of a possible physiological role of this channel in the olfactory system by asking whether Ca2+ can activate Cl- currents mediated by TMEM16A. We use whole-cell patch-clamp analysis in slices of the olfactory epithelium to measure dose-response relations in the presence of various intracellular Ca2+ concentrations, ion selectivity, and blockage. We find that knockout of TMEM16A abolishes Ca2+-activated Cl- currents, demonstrating that TMEM16A is essential for these currents in supporting cells. Also, by using extracellular ATP as physiological stimuli, we found that the stimulation of purinergic receptors activates a large TMEM16A-dependent Cl- current, indicating a possible role of TMEM16A in ATP-mediated signaling. Altogether, our results establish that TMEM16A-mediated currents are functional in olfactory supporting cells and provide a foundation for future work investigating the precise physiological role of TMEM16A in the olfactory system
    • …
    corecore