43 research outputs found

    Generating functional of correlators of twist-22 operators in N=1\mathcal{N} = 1 SUSY Yang-Mills theory, I

    Full text link
    Extending our previous work in pure Yang-Mills (YM) theory, we compute the generating functional of correlators of collinear twist-22 operators that enter the components of balanced superfields -- i.e., superfields with an equal number of dotted and undotted indices in their spinor representation -- in N=1\mathcal{N} = 1 SUSY SU(NN) YM theory in Minkowskian and Euclidean space-time, in the conformal limit and renormalization-group improved form, and to the leading and next-to-leading order in the large-NN expansion. The latter calculation sets strong UV asymptotic constraints on the nonperturbative solution of large-NN N=1\mathcal{N} = 1 SUSY YM theory that may be a pivotal guide for the search of such a solution.Comment: 57 page

    On the structure of the large-NN expansion in SU(NN) Yang-Mills theory

    Full text link
    Recently, we have computed the short-distance asymptotics of the generating functional of Euclidean correlators of single-trace twist-22 operators in the large-NN expansion of SU(NN) Yang-Mills (YM) theory to the leading-nonplanar order. Remarkably, it has the structure of the logarithm of a functional determinant, but with the sign opposite to the one that would follow from the spin-statistics theorem for the glueballs. In order to solve this sign puzzle, we have reconsidered the proof in the literature that in the 't Hooft topological expansion of large-NN YM theory the leading-nonplanar contribution to the generating functional consists of the sum over punctures of nn-punctured tori. We have discovered that for twist-22 operators it contains -- in addition to the nn-punctured tori -- the normalization of tori with 1pn1 \leq p \leq n pinches and npn-p punctures. Once the existence of the new sector is taken into account, the violation of the spin-statistics theorem disappears. Moreover, the new sector contributes trivially to the nonperturbative SS matrix because -- for example -- the nn-pinched torus represents nonperturbatively a loop of nn glueball propagators with no external leg. This opens the way for an exact solution limited to the new sector that may be solvable thanks to the vanishing SS matrix.Comment: 12 pages, 16 figure

    The good, the bad and the ugly: Emys trinacris, Placobdella costata and Haemogregarina stepanowi in Sicily (Testudines, Annelida and Apicomplexa)

    Get PDF
    Endemic Sicilian pond turtles Emys trinacris Fritz, Fattizzo, Guicking, Tripepi, Pennisi, Lenk, Joger et Wink were examined for the presence of haemogregarine parasites. The presence of haemogregarines, occurring mainly in the microgametocyte stage (13.2 ± 0.12 μm in length and 6.4 ± 0.52 μm in width), was observed in approximately 9% of the sampled E. trinacris. Based on the observed morphology and on the sequencing of nuclear 18S rDNA, we identified the parasite as Haemogregarina stepanowi Danilewsky, 1885. Morphometric study of uninfected and infected red blood cells has shown that H. stepanowi induces different changes in erythrocyte shape depending on the infective stage. The differential count of leukocytes in specimens infected with H. stepanowi showed no significant difference compared with healthy specimens. However, considering the health problems which might be induced by H. stepanowi in the closely related European pond turtle Emys orbicularis (Linneaus), monitoring of the health status of the infected Sicilian populations of E. trinacris is desirable. The restricted distribution of populations of Emys infected with haemogregarines in Sicily is quite puzzling and the possible human-mediated introduction of the parasite in Sicily is briefly discussed

    CubeSat attitude estimation via AUKF using magnetometer measurements and MRPs

    Get PDF
    In this article the Attitude and Control system of a CubeSat is presented. The attitude estimation design approach used is based on Adaptative Unscented Kalman Filter (AUKF) using three-axis magnetometer measurements. A set of modified Rodrigues Parameters (MRPs) is used to evaluate the attitude. Finally in order to have an complete ADCS system two control laws are introduced (Bdot and Sliding Mode) to best simulate a real CubeSat mission. The first one allows the spacecraft the control during the detumbling phase (phase at high angular rates) and in case of reaction wheels saturation and the second one is used for the nominal control (phase at low angular rates)

    New evidence of MIS 3 relative sea level changes from the Messina Strait, Calabria (Italy)

    Get PDF
    © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Antonioli, F., Calcagnile, L., Ferranti, L., Mastronuzzi, G., Monaco, C., Orru, P., Quarta, G., Pepe, F., Scardino, G., Scicchitano, G., Stocchi, P., & Taviani, M. New evidence of MIS 3 relative sea level changes from the Messina Strait, Calabria (Italy). Water, 13(19), (2021): 2647, https://doi.org/10.3390/w13192647.Investigation of sea-level positions during the highly-dynamic Marine Isotope Stage 3 (MIS 3: 29–61 kyrs BP) proves difficult because: (i) in stable and subsiding areas, coeval coastal sediments are currently submerged at depths of few to several tens of meters below the present sea level; (ii) in uplifting areas, the preservation of geomorphic features and sedimentary records is limited due to the erosion occurred during the Last Glacial Maximum (LGM) with sea level at a depth of −130 m, followed by marine transgression that determined the development of ravinement surfaces. This study discusses previous research in the Mediterranean and elsewhere, and describes new fossiliferous marine deposits overlaying the metamorphic bedrock at Cannitello (Calabria, Italy). Radiocarbon ages of marine shells (about 43 kyrs cal BP) indicate that these deposits, presently between 28 and 30 m above sea level, formed during MIS 3.1. Elevation correction of the Cannitello outcrops (considered in an intermediate-to-far-field position with respect to the ice sheet) with the local vertical tectonic rate and Glacial Isostatic Adjustment (GIA) rate allows the proposal of a revision of the eustatic depth for this highstand. Our results are consistent with recently proposed estimates based on a novel ice sheet modelling technique.This research received no external funding

    Relative Sea-Level Rise and Potential Submersion Risk for 2100 on 16 Coastal Plains of the Mediterranean Sea.

    Get PDF
    The coasts of the Mediterranean Sea are dynamic habitats in which human activities have been conducted for centuries and which feature micro-tidal environments with about 0.40 m of range. For this reason, human settlements are still concentrated along a narrow coastline strip, where any change in the sea level and coastal dynamics may impact anthropic activities. In the frame of the RITMARE and the Copernicus Projects, we analyzed light detection and ranging (LiDAR) and Copernicus Earth Observation data to provide estimates of potential marine submersion for 2100 for 16 small-sized coastal plains located in the Italian peninsula and four Mediterranean countries (France, Spain, Tunisia, Cyprus) all characterized by different geological, tectonic and morphological features. The objective of this multidisciplinary study is to provide the first maps of sea-level rise scenarios for 2100 for the IPCC RCP 8.5 and Rahmstorf (2007) projections for the above affected coastal zones, which are the locations of touristic resorts, railways, airports and heritage sites. On the basis of our model (eustatic projection for 2100, glaciohydrostasy values and tectonic vertical movement), we provide 16 high-definition submersion maps. We estimated a potential loss of land for the above areas of between about 148 km(2)(IPCC-RCP8.5 scenario) and 192 km(2)(Rahmstorf scenario), along a coastline length of about 400 km

    Regional deformation and offshore crustal local faulting as combined processes to explain uplift through time constrained by investigating differentially-uplifted Late Quaternary palaeoshorelines: the foreland Hyblean Plateau, SE Sicily

    Get PDF
    Quaternary uplift is well documented in SE Sicily, a region prone to damaging seismic events, such as the 1693 “Val di Noto” Earthquake (Mw 7.4), the largest seismic event reported within the Italian Earthquake Catalogue, whose seismogenic source is still debated and, consequently, the long-term seismic hazard is poorly-understood. However, the spatial variation in the timing and rates of uplift are still debated, so it is difficult to link the dominant tectonic process(es) responsible for the uplift and the location of seismogenic sources. To better constrain the uplift rate, we have refined the dating of Late Quaternary marine terraces, using a synchronous correlation approach, driven by both published and newly obtained numerical age controls (234U/230Th dating on corals). This has allowed re-calculation of uplift rates along a N-S oriented transect within the Hyblean Plateau (HP) foreland region. Consequently, we have mapped the geometry of palaeoshorelines along a coastline-parallel transect, and hence the rates of uplift. The results suggest increasing uplift rate from south to north across the HP, and that uplift rates have remained constant through the late Quaternary. This spatially-changing but temporally constant uplift places constraints on the proportion of uplift produced by regional geodynamic processes versus produced by local faults, such as an offshore E-dipping active normal fault. We discuss these new findings in terms of the long-term seismic hazard for one of the most seismically-active regions in the Mediterranean Basin

    Safety and Feasibility of MitraClip Implantation in Patients with Acute Mitral Regurgitation after Recent Myocardial Infarction and Severe Left Ventricle Dysfunction

    Get PDF
    Patients with severe mitral regurgitation (MR) after myocardial infarction (MI) have an increased risk of mortality. Transcatheter mitral valve repair may therefore be a suitable therapy. However, data on clinical outcomes of patients in an acute setting are scarce, especially those with reduced left ventricle (LV) dysfunction. We conducted a multinational, collaborative data analysis from 21 centers for patients who were, within 90 days of acute MI, treated with MitraClip due to severe MR. The cohort was divided according to median left ventricle ejection fraction (LVEF)-35%. Included in the study were 105 patients. The mean age was 71 ± 10 years. Patients in the LVEF \u3c 35% group were younger but with comparable Euroscore II, multivessel coronary artery disease, prior MI and coronary artery bypass graft surgery. Procedure time was comparable and acute success rate was high in both groups (94% vs. 90%, p = 0.728). MR grade was significantly reduced in both groups along with an immediate reduction in left atrial V-wave, pulmonary artery pressure and improvement in New York Heart Association (NYHA) class. In-hospital and 1-year mortality rates were not significantly different between the two groups (11% vs. 7%, p = 0.51 and 19% vs. 12%, p = 0.49) and neither was the 3-month re-hospitalization rate. In conclusion, MitraClip intervention in patients with acute severe functional mitral regurgitation (FMR) due to a recent MI in an acute setting is safe and feasible. Even patients with severe LV dysfunction may benefit from transcatheter mitral valve intervention and should not be excluded

    Properties and customization of sensor materials for biomedical applications.

    Get PDF
    Low-power chemo- and biosensing devices capable of monitoring clinically important parameters in real time represent a great challenge in the analytical field as the issue of sensor calibration pertaining to keeping the response within an accurate calibration domain is particularly significant (1–4). Diagnostics, personal health, and related costs will also benefit from the introduction of sensors technology (5–7). In addition, with the introduction of Registration, Evaluation, Authorization, and Restriction of Chemical Substances (REACH) regulation, unraveling the cause–effect relationships in epidemiology studies will be of outmost importance to help establish reliable environmental policies aimed at protecting the health of individuals and communities (8–10). For instance, the effect of low concentration of toxic elements is seldom investigated as physicians do not have means to access the data (11)

    n-point correlators of twist-2 operators in SU(N) Yang-Mills theory to the lowest perturbative order

    No full text
    We compute, to the lowest perturbative order in SU(N) Yang-Mills theory, n-point correlators in the coordinate and momentum representation of the gauge-invariant twist-2 operators with maximal spin along the p+ direction, both in Minkowskian and — by analytic continuation — Euclidean space-time. We also construct the corresponding generating functionals. Remarkably, they have the structure of the logarithm of a functional determinant of the identity plus a term involving the effective propagators that act on the appropriate source fields
    corecore