On the stability of travelling waves with vorticity obtained by minimisation

We modify the approach of Burton and Toland [Comm. Pure Appl. Math. (2011)] to show the existence of periodic surface water waves with vorticity in order that it becomes suited to a stability analysis. This is achieved by enlarging the function space to a class of stream functions that do not correspond necessarily to travelling profiles. In particular, for smooth profiles and smooth stream functions, the normal component of the velocity field at the free boundary is not required a priori to vanish in some Galilean coordinate system. Travelling periodic waves are obtained by a direct minimisation of a functional that corresponds to the total energy and that is therefore preserved by the time-dependent evolutionary problem (this minimisation appears in Burton and Toland after a first maximisation). In addition, we not only use the circulation along the upper boundary as a constraint, but also the total horizontal impulse (the velocity becoming a Lagrange multiplier). This allows us to preclude parallel flows by choosing appropriately the values of these two constraints and the sign of the vorticity. By stability, we mean conditional energetic stability of the set of minimizers as a whole, the perturbations being spatially periodic of given period.Comment: NoDEA Nonlinear Differential Equations and Applications, to appea

Learning the noise fingerprint of quantum devices

Noise sources unavoidably affect any quantum technological device. Noise's main features are expected to strictly depend on the physical platform on which the quantum device is realized, in the form of a distinguishable fingerprint. Noise sources are also expected to evolve and change over time. Here, we first identify and then characterize experimentally the noise fingerprint of IBM cloud-available quantum computers, by resorting to machine learning techniques designed to classify noise distributions using time-ordered sequences of measured outcome probabilities.Comment: 20 pages, 3 figures, 5 tables, research articl

Reconstruction of daily pressure maps over Italy during some extreme events of the 19th Century

The quality and availability of daily meteorological data for the reconstruction of atmospheric circulation over Italy in the period between the Italian political Unity (1860) and the development of the Central Office for Meteorology (1879) is studied. Examples of atmospheric circulation reconstructed for some extreme events are presented

A dimension-breaking phenomenon for water waves with weak surface tension

It is well known that the water-wave problem with weak surface tension has small-amplitude line solitary-wave solutions which to leading order are described by the nonlinear Schr\"odinger equation. The present paper contains an existence theory for three-dimensional periodically modulated solitary-wave solutions which have a solitary-wave profile in the direction of propagation and are periodic in the transverse direction; they emanate from the line solitary waves in a dimension-breaking bifurcation. In addition, it is shown that the line solitary waves are linearly unstable to long-wavelength transverse perturbations. The key to these results is a formulation of the water wave problem as an evolutionary system in which the transverse horizontal variable plays the role of time, a careful study of the purely imaginary spectrum of the operator obtained by linearising the evolutionary system at a line solitary wave, and an application of an infinite-dimensional version of the classical Lyapunov centre theorem.Comment: The final publication is available at Springer via http://dx.doi.org/10.1007/s00205-015-0941-

Numerical Investigation, Including Experimental Validation, of an Axially Blown, Stable Arc in Argon

In this work we present the outcome of a numerical validation study conducted with an arc model developed within a computational fluid dynamics (CFD) tool. The numerical investigations were aimed at reproducing the spatially resolved temperature data obtained with an experiment in which an axially symmetric argon arc was established in the observation region. The full absorption spectrum has been computed for argon and then compressed with minimum loss of information to a relatively small set of bands. The latter has been used for solving the radiative transfer equation in a computationally affordable, yet accurate way. The comparison between the arc temperature simulated with the reduced absorption data and the measured one is presented

LIGHT as regulator of bone homeostasis during osteolytic bone metastasis formation in non-small cell lung cancer patients

Tumor necrosis factor superfamily member 14 (TNFSF14), LIGHT is one of the cytokines produced by tumor and immune cells, which promotes homeostasis of lymphoid organs, liver and bone. Nonsmall cell lung cancer (NSCLC) commonly metastasizes bone, altering bone homeostasis and causing osteolysis. Here we investigated the role of LIGHT in NSCLC-induced osteolytic bone disease. The LIGHT expression in monocytes was higher in patients with metastatic bone lesions than in non-bone metastatic ones (66.5 ± 24.5 vs 43.3 ± 25.2 mean ± SD, p = 0.001), in healthy donors (66.5 ± 24.5 vs 8.5 ± 4.6 p = 0.0002), and in non-bone metastatic patients than in healthy donors (43.3 ± 25.2 vs 8.5 ± 4.6, p = 0.0001). Serum LIGHT levels were also significantly higher in bone metastatic patients than in non-bone metastatic ones (186.8 ± 191.2 pg/ml vs 115.8 ± 73 pg/ml, p = 0.04) and in healthy donors (186.8 ± 191.2 pg/ml vs 85.7 ± 38.4 pg/ml, p = 0.04). A neutralizing mAb anti-LIGHT added to osteoclast (OC) cultures of both bone and non-bone metastases inhibited osteoclastogenesis, but the decrease was statistically significant only for bone metastatic patients (272 ± 98 vs 132 ± 74, p = 0.01). To investigate the role of LIGHT in NSCLC- induced bone lesion in vivo, we performed an intratibial injection of a mouse lung cancer cell line LLC-1, in wild-type (WT) and LIGHT KO mice. The WT-injected mice displayed a significant reduction of about 20% for BV/TV, Tb.N, Tb.Th, and Tb.Sp compared to the WT-vehicle mice (pb 0.01). These parameters did not show significant variation for KO-injected mice vs vehicle or for WT-injected mice vs KO-injected mice. These data indicate LIGHT as a regulator of bone homeostasis during NSCLC metastatic invasion, thus it may be a novel therapeutic target in osteolytic bone metastases

Distribution of Foxp3+ T cells in the liver and hepatic lymph nodes of goats and sheep experimentally infected with Fasciola hepatica

Foxp3 regulatory T cells (Tregs) are now considered to play a key role in modulation of immune responses during parasitic helminth infections. Immunomodulation is a key factor in Fasciola hepatica infection; however, the distribution and role of Foxp3+ Tregs cells have not been investigated in F. hepatica infected ruminants. The aim of this study was to evaluate the presence of Foxp3+ Tregs in the liver and hepatic lymph nodes from experimentally infected sheep and goats during acute and chronic stages of infection. Three groups of goats (n=6) and three groups of sheep (n=6) were used in this study. Goats in groups 1-2 and sheep in groups 4-5 were orally infected with metacercarie of ovine origin. Groups 1 and 4 were killed during the acute stage of the infection, at nine days post infection (dpi); groups 2 and 5 were killed during the chronic stage, at 15 and19 weeks post infection respectively (wpi). Groups 3 (goats) and 6 (sheep) were left as uninfected controls. Fluke burdens and liver damage were assessed and the avidin-biotin-complex method was used for the immunohistochemical study. At nine dpi in acute hepatic lesions, the number of both Foxp3+ and CD3+ T lymphocytes increased significantly in goats and sheep. In the chronic stages of infection (15-19wpi), the number of Foxp3+ and CD3+ T lymphocytes were also significantly increased with respect to control livers, particularly in portal spaces with severely enlarged bile ducts (response to adult flukes) while the increase was lower in granulomas, chronic tracts and smaller portal spaces (response to tissue damage). Foxp3+ Tregs were increased in the cortex of hepatic lymph nodes of sheep (chronic infection) and goats (acute and chronic infection). The estimated proportion of T cells which were Foxp3+ was significantly increased in the large bile ducts and hepatic lymph node cortex of chronically infected goats but not sheep. This first report of the expansion of Foxp3+ Tregs in acute and chronic hepatic lesions in ruminants suggests that these cells may be involved in both parasite survival and modulation of hepatic damage. Future studies should be focused on the investigation of parasite molecules and cytokines involved in this process.This work was supported by EU grants (H2020-635408-PARAGONE) and the Spanish Ministry of Science grant AGL2015-67023-C2-1-R. TM receives funding from the Scottish Government.Accepted manuscriptVeterinari

Comparative dynamics of peritoneal cell immunophenotypes in sheep during the early and late stages of the infection with Fasciola hepatica by flow cytometric analysis

Background: The peritoneal cell populations (PCP) are thought to play a crucial role during the early immune response in Fasciola hepatica infection while newly excysted juveniles (NEJ) are migrating in the peritoneal cavity (PC) towards the liver. In this study, we aimed to determine the immunophenotypes of the PCP and to analyse the dynamics of the recruitment of the PCP during the early and late stage of the infection in sheep infected with F. hepatica. Methods: Thirty-seven sheep were divided into three groups: Group 1 (n = 20) and 2 (n = 10) were challenged with F. hepatica, Group 3 (n = 7) was not infected and remained as uninfected control (UC). After the slaughtering, peritoneal lavages were carried out to isolate peritoneal cell populations at 1, 3, 9 and 18 days post-infection (dpi) for Group 1 and at 14 weeks post-infection (wpi) for Group 2 and 3. Flow cytometry was conducted to assess the dynamics of peritoneal cavity cell populations. Results: TCD4 cells showed a significant decrease at 1 and 18 dpi when compared to UC; no statistical differences were detected for TCD8 and WC1+ γδ during the early stage of the infection with respect to the UC. CD14 cells exhibited a decreasing trend, with a significant decrease at 9 and 18 dpi when compared to the UC. The dynamics of MHCII and CD83 cells showed a similar increasing pattern from 3 to 18 dpi. During the chronic stage, both TCD4 and TCD8 cells showed no significant differences when compared to the UC, although a slight but statistically significant higher level of WC1+ γδ cells was observed. A lower percentage of antigen-presenting cells (APCs) was detected with respect to the UC. Conclusions: The recruitment of the lymphocytes subsets did not show a significant increase during the course of the infection and only WC1+ γδ cells displayed a significant increase at the chronic stage. For the CD14, a decreasing trend was observed during the early stage, which was statistically significant at the chronic stage of the infection. Peritoneal CD83 and MHCII cells developed an increasing trend during the early stage of infection, and showed a significant decrease at the late stage of the infection.This study was funded by the European Union Grant H2020-635408- PARAGONE and by National Grant AGL2015-67023-C2-1-R. RPC was supported by an FPU grant of the Spanish Ministry of Education, Culture and Sport. Funding bodies were neither involved in the design of the study nor in analysis and interpretation of the dataVeterinari