ABSTRACT
We develop a machine learning algorithm to infer the three-dimensional cumulative radial profiles of total and gas masses in galaxy clusters from thermal Sunyaev–Zel’dovich effect maps. We ...generate around 73 000 mock images along various lines of sight using 2522 simulated clusters from the three hundred project at redshift z < 0.12 and train a model that combines an auto-encoder and a random forest. Without making any prior assumptions about the hydrostatic equilibrium of the clusters, the model is capable of reconstructing the total mass profile as well as the gas mass profile, which is responsible for the Sunyaev–Zel’dovich effect. We show that the recovered profiles are unbiased with a scatter of about 10 per cent, slightly increasing towards the core and the outskirts of the cluster. We selected clusters in the mass range of $10^{13.5} \le M_{200} /({{\, h^{-1}\,{\rm {{\rm M}_{\odot }}}) \le 10^{15.5}$, spanning different dynamical states, from relaxed to disturbed haloes. We verify that both the accuracy and precision of this method show a slight dependence on the dynamical state, but not on the cluster mass. To further verify the consistency of our model, we fit the inferred total mass profiles with a Navarro–Frenk–White model and contrast the concentration values with those of the true profiles. We note that the inferred profiles are unbiased for higher concentration values, reproducing a trustworthy mass–concentration relation. The comparison with a widely used mass estimation technique, such as hydrostatic equilibrium, demonstrates that our method recovers the total mass that is not biased by non-thermal motions of the gas.
The determination of the mass of galaxy clusters from observations is subject to systematic uncertainties. Beyond the errors due to instrumental and observational systematic effects, in this work we ...investigate the bias introduced by modelling assumptions. In particular, we consider the reconstruction of the mass of galaxy clusters from convergence maps employing spherical mass density models. We made use of THE THREE HUNDRED simulations, selecting clusters in the same redshift and mass range as the NIKA2 Sunyaev-Zel’dovich Large Programme sample: 3 ≤ M500/1014 M⊙ ≤ 10 and 0.5 ≤ z ≤ 0.9. We studied different modelling and intrinsic uncertainties that should be accounted for when using the single cluster mass estimates for scaling relations. We confirm that the orientation of clusters and the radial ranges considered for the fit have an important impact on the mass bias. The effect of the projection adds uncertainties to the order of 10–16% to the mass estimates. We also find that the scatter from cluster to cluster in the mass bias when using spherical mass models is less than 9% of the true mass of the clusters.
Background Specific immunotherapy (SIT) is a recognized way of treating IgE‐mediated respiratory diseases. The clinical outcome is usually better in allergic children than in adults.
Objective To ...increase our knowledge of the ability of SIT to prevent the onset of new sensitizations in monosensitized subjects, so far poorly documented.
Methods 134 children (age range 5–8 years), who had intermittent asthma with or without rhinitis, with single sensitization to mite allergen (skin prick test and serum‐specific IgE), were enrolled. SIT was proposed to all the children's parents, but was accepted by only 75 of them (SIT Group). The remaining 63 children were treated with medication only, and were considered the Control Group. Injective SIT with mite mix was administered to the SIT Group during the first three years and all patients were followed for a total of 6 years. All patients were checked for allergic sensitization(s) by skin prick test and serum‐specific IgE every year until the end of the follow‐up period.
Results Both groups were comparable in terms of age, sex and disease characteristics. 123 children completed the follow‐up study. At the end of the study, 52 out of 69 children (75.4%) in the SIT Group showed no new sensitization, compared to 18 out of 54 children (33.3%) in the Control Group (P < 0.0002). Parietaria, Gramineae and Olea were the most common allergens responsible for the new sensitization(s).
Conclusions According to our data, SIT may prevent the onset of new sensitizations in children with respiratory symptoms monosensitized to house dust mite (HDM).
GABA depolarized sural nerve axons and increased the electrical excitability of C-fibres via GABA
receptor. Axonal excitability responses to GABA increased monotonically with the rate of action ...potential firing. Action potential activity in unmyelinated C-fibres is coupled to Na-K-Cl cotransporter type 1 (NKCC1) loading of axonal chloride. Activation of axonal GABA
receptor stabilized C-fibre excitability during prolonged low frequency (2.5 Hz) firing. NKCC1 maintains intra-axonal chloride to provide feed-forward stabilization of C-fibre excitability and thus support sustained firing.
GABA
receptor (GABA
R)-mediated depolarization of dorsal root ganglia (DRG) axonal projections in the spinal dorsal horn is implicated in pre-synaptic inhibition. Inhibition, in this case, is predicated on an elevated intra-axonal chloride concentration and a depolarizing GABA response. In the present study, we report that the peripheral axons of DRG neurons are also depolarized by GABA and this results in an increase in the electrical excitability of unmyelinated C-fibre axons. GABA
R agonists increased axonal excitability, whereas GABA excitability responses were blocked by GABA
R antagonists and were absent in mice lacking the GABA
R β3 subunit selectively in DRG neurons (Advillin
or sns
). Under control conditions, excitability responses to GABA became larger at higher rates of electrical stimulation (0.5-2.5 Hz). However, during Na-K-Cl cotransporter type 1 (NKCC1) blockade, the electrical stimulation rate did not affect GABA response size, suggesting that NKCC1 regulation of axonal chloride is coupled to action potential firing. To examine this, activity-dependent conduction velocity slowing (activity-dependent slowing; ADS) was used to quantify C-fibre excitability loss during a 2.5 Hz challenge. ADS was reduced by GABA
R agonists and exacerbated by either GABA
R antagonists, β3 deletion or NKCC1 blockade. This illustrates that activation of GABA
R stabilizes C-fibre excitability during sustained firing. We posit that NKCC1 acts in a feed-forward manner to maintain an elevated intra-axonal chloride in C-fibres during ongoing firing. The resulting chloride gradient can be utilized by GABA
R to stabilize axonal excitability. The data imply that therapeutic strategies targeting axonal chloride regulation at peripheral loci of pain and itch may curtail aberrant firing in C-fibres.
We explore the ground-state properties of the two-band Hubbard model with degenerate electronic bands, parametrized by nearest-neighbor hopping t, intra- and interorbital on-site Coulomb repulsions U ...and U′, and Hund coupling J, focusing on the case with J>0. Using Jastrow-Slater wave functions, we consider both states with and without magnetic/orbital order. Electron pairing can also be included in the wave function, in order to detect the occurrence of superconductivity for generic electron densities n. When no magnetic/orbital order is considered, the Mott transition is continuous for n=1 (quarter filling); instead, at n=2 (half filling), it is first order for small values of J/U, while it turns out to be continuous when the ratio J/U is increased. A significant triplet pairing is present in a broad region around n=2. By contrast, singlet superconductivity (with d-wave symmetry) is detected only for small values of the Hund coupling and very close to half filling. When including magnetic and orbital order, the Mott insulator acquires antiferromagnetic order for n=2; instead, for n=1 the insulator has ferromagnetic and antiferro-orbital orders. In the latter case, a metallic phase is present for small values of U/t and the metal-insulator transition becomes first order. In the region with 1<n<2, we observe that ferromagnetism (with no orbital order) is particularly robust for large values of the Coulomb repulsion and that triplet superconductivity is strongly suppressed by the presence of antiferromagnetism. The case with J=0, which has an enlarged SU(4) symmetry due to the interplay between spin and orbital degrees of freedom, is also analyzed.
The intra-cluster medium is prone to turbulent motion that will contribute to the non-thermal heating of the gas, complicating the use of galaxy clusters as cosmological probes. Indirect approaches ...can estimate the intensity and structure of turbulent motions by studying the associated fluctuations in gas density and X-ray surface brightness. In this work, we aim to constrain the gas density fluctuations occurring in the CHEX-MATE sample to obtain a detailed view of their properties in a large population of clusters. To do so, we use a simulation-based approach to constrain the parameters of the power spectrum of density fluctuations, assuming a Kolmogorov-like spectrum and including the stochastic nature of the fluctuation-related observables in the error budget. Using a machine-learning approach, we learn an approximate likelihood for each cluster. This method requires clusters not to be too disturbed, as fluctuations can originate from dynamic processes such as merging. Accordingly, we removed the less relaxed clusters (centroid shift w > 0.02) from our sample, resulting in a sample of 64 clusters. We defined different subsets of CHEX-MATE to determine properties of density fluctuations as a function of dynamical state, mass, and redshift, and we investigated the correlation with the presence or not of a radio halo. We found a positive correlation between the dynamical state and density fluctuation variance, a non-trivial behaviour with mass, and no specific trend with redshift or the presence of a radio halo. The injection scale is mostly constrained by the core region. The slope in the inertial range is consistent with the Kolmogorov theory. When interpreted as originating from turbulent motion, the density fluctuations in R 500 yield an average Mach number of ℳ 3D ≃ 0.4 ± 0.2, an associated non-thermal pressure support of P turb / P tot ≃ (9 ± 6)%, or a hydrostatic mass bias b turb ≃ 0.09 ± 0.06. These findings align with expectations from existing literature.
The ro-ro ships are characterized by a large garage compartment extending from stern to bow. Damage conditions, heavy weather and large floodable spaces could create serious accidents, with the loss ...of life and goods at sea, both for conventional ferries and fast ferries. The occurred accidents showed the need of a more accurate approach to the damaged ship stability in waves, also in head sea and following sea conditions, because of the great movements of water on the car deck. With this aim a tool for analysing the ship response in wave with damaged compartments has been developed and applied on a typical fast ferry. The ship dynamic is simulated in time domain, including non-linear effects, taking into account critical scenarios on the damaged ship. The applications regard ship grounding, assuming head sea, modelled by regular wave. In addition to that, also the particularly critical condition of a transversal wind heeling moment has been applied to compute non symmetrical behaviour. Moreover the stability problems arising from the presence of trapped water in the garage compartment are investigated assuming the same environmental scenarios.
Right-parasternal-view (RPV) often provides the best hemodynamic assessment of the aortic-valve-stenosis by echocardiography. However, no detailed study on patients with aortic prosthesis is ...available. Thus, RPV usefulness is left as an anecdotical notion in this context. We aimed to define feasibility and clinical-impact of RPV before and soon-after percutaneous implantation (TAVI) or surgical (SAVR) aortic-valve-replacement (AVR) for AS. Patients with severe-AS electively referred for AVR between September-2019 and February-2020 were prospectively evaluated. Echocardiographic examinations inclusive of apical and RPV to measure aortic-peak-velocity , gradients and area (AVA) were performed the day before AVR and at hospital discharge and compared by matched-pair-analysis. Forty-seven patients (mean age 79 ± 8 years, 63% female, ejection-fraction 61 ± 6%) referred for SAVR (24 51%) or TAVI (23 49%) were enrolled. RPV was feasible in 45 patients (96%) before-AVR but in only 32 after-AVR (68%), particularly after SAVR (50%) than TAVI (87% p = 0.005). RPV remained the best acoustic window after TAVI in 75% of cases. Hemodynamic assessment of TAVI, but not SAVR, invariably benefit from RPV versus apical evaluation (aortic-peak-velocity: 2.57 ± 0.39 vs 2.23 ± 0.47 m/sec, p = 0.002; mean gradient: 15 ± 5 vs 12 ± 5 mm Hg, p = 0.01). Five (11%) patients presented severe patient-prosthesis-mismatch, 4 of which were detectable only by RPV. This pilot-experience demonstrates that RPV feasibility is slightly reduced after AVR. RPV can improve the hemodynamic assessment of the prosthetic valve versus apical view, including the detection of patient-prosthesis-mismatch. Furthermore, when RPV is the best acoustic windows in patients with severe AS, it generally remains so after-TAVI.
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