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Nanostructured semiconducting alloys obtain ultra-low thermal conductivity as a result of the scattering of phonons with a wide range of mean-free-paths (MFPs). In these materials, long-MFP phonons are scattered at the nanoscale boundaries whereas short-MFP high-frequency phonons are impeded by disordered point defects introduced by alloying. While this trend has been validated by simplified analytical and numerical methods, an ab-initio space-resolved approach remains elusive. To fill this gap, we calculate the thermal conductivity reduction in porous alloys by solving the mode-resolved Boltzmann transport equation for phonons using the finite-volume approach. We analyze different alloys, length-scales, concentrations, and temperatures, obtaining a very large reduction in the thermal conductivity over the entire configuration space. For example, a ~97% reduction is found for Al$_{0.8}$In$_{0.2}$As with 25% porosity. Furthermore, we employ these simulations to validate our recently introduced "Ballistic Correction Model" (BCM), an approach that estimates the effective thermal conductivity using the characteristic MFP of the bulk alloy and the length-scale of the material. The BCM is then used to provide guiding principles in designing alloy-based nanostructures. Notably, it elucidates how porous alloys such as Si$_{x}$Ge$_{1-x}$ obtain larger thermal conductivity reduction compared to porous Si or Ge, while also explaining why we should not expect similar behavior in alloys such as Al$_{x}$In$_{1-x}$As. By taking into account the synergy from scattering at different scales, we provide a route for the design of materials with ultra-low thermal conductivity.

Controlling heat flow at the nanoscales is pivotal to several applications, including thermal energy harvesting and heat management. However, engineering nanostructures is challenging because phonon-boundary interaction, not contemplated by Fourier's law, must be taken into account. Nondiffusive models, such as the Boltzmann transport equation (BTE), have been successfully employed to capture size effects in complex structures; however, their widespread has been hindered by the limited offer of open-source solvers in this space. We fill this void by introducing OpenBTE, an efficient solver for the steady-state phonon BTE in multidimensional structures. This tool is interfaced to first-principles calculations, thus it unlocks the calculations of thermal-related properties with no fitting-parameters. As an example, we employ OpenBTE to compute the temperature and flux maps, as well as the mode-resolved, effective thermal conductivity of Si membranes with infinite and finite thickness. By unlocking fast nanoscale heat transport simulations, OpenBTE may help accelerate the design of nanomaterials for thermal energy applications.

First-principles calculations of thermal transport in homogeneous materials have reached remarkable predicting power. Modeling deterministically phonon transport in nanostructures, however, poses novel challenges; notably, it entails solving as many algebraic equations as the number of combinations of wave vectors in the discretized Brillouen and polarizations. We show that, within the relaxation time approximation of the Boltzmann transport equation (BTE), this issue is resolved by interpolating the phonon distributions in the vectorial phonon mean free paths (MFP) space. The coupling between structure and mode-resolved heat transport is investigated in terms of angular-resolved bulk thermal conductivity and phonon suppression function, the latter being associated primarily to the material's geometry. Our method, termed the anisotropic MFP-BTE (aMFP-BTE), allows for fast and accurate thermal conductivity calculations in nanomaterials regardless of the number of phonon branches and wave vectors. Furthermore, it naturally blends with first-principles thermal transport calculations, therefore allowing for multiscale, parameter-free simulations. We apply the aMFP-BTE to compute the mode-resolved effective thermal conductivity of porous Si membranes, achieving up to 50x speed with respect to the case with no interpolation. The proposed approach unlocks the engineering of novel nanostructures, with applications to thermoelectrics and heat management.

Left ventricular intramyocardial fat (LV-IMF) is often found in patients with previous irreversible myocardial damage and may be detected by cardiac magnetic resonance (CMR). No data are currently available about the prevalence of LV-IMF in patients with previous myocarditis. Our aim was to assess the prevalence of LV-IMF in patients with previous myocarditis by repeating after3 years a follow-up CMR examination and to evaluate its clinical and prognostic role. Patients with clinical suspected myocarditis who underwent CMR within the first week from the onset of their symptoms and underwent repeated CMR were enrolled. LV-IMF was detected as areas of left ventricular intramyocardial "India ink" black boundary with or without a hyperintense core. Overall, in 235 patients with a definitive diagnosis of acute myocarditis, CMR was repeated after a median of 4 (3 to 6) years from symptom onset. LV-IMF positive patients (n = 35, 15%) presented greater ventricular volumes and more frequently a mid-wall late gadolinium enhancement than those without LV-IMF (both p0.05). Patients presenting major cardiac events (sudden cardiac deaths, resuscitated cardiac arrest, and appropriate implantable cardioverter-defibrillator-firing) at follow-up had a greater prevalence of LV-IMF than those without (55% vs 11%, p0.001). Patients with LV-IMF had a higher incidence myocarditis relapse (27% vs 9%, p = 0.003) and a greater risk of major cardiac events (p0.0001) than those without. At logistic regression analysis, LV-IMF was an independent predictor of major cardiac events. In conclusion, LV-IMF is not an uncommon finding in patients with previous myocarditis and is associated with worse ventricular remodeling and prognosis.

Phonon size effects induce ballistic transport in nanomaterials, challenging Fourier's law. Nondiffusive heat transport is captured by the Peierls-Boltzmann transport equation (BTE), commonly solved under the relaxation time approximation (RTA), which assumes diagonal scattering operator. Although the RTA is accurate for many relevant materials over a wide range of temperatures, such as silicon, it underpredicts thermal transport in most two-dimensional (2D) systems, notoriously graphene. Here we present a formalism, based on the BTE with the full collision matrix, for computing the effective thermal conductivity of arbitrarily patterned 2D materials. We apply our approach to porous graphene and find strong heat transport suppression in configurations with feature sizes of the order of micrometers; this result, which is rooted in the large generalized phonon MFPs in graphene, corroborates the possibility of strong thermal transport tunability by relatively coarse patterning. Lastly, we present a promising material configuration with low thermal conductivity. Our method enables the parameter-free design of 2D materials for thermoelectric and thermal routing applications.

We read with interest the paper of Tarvasmaki et al. [1] regarding the role of inotropes and vasopressors in patients with cardiogenic shock. The authors should be congratulated for their effort of prospectively collecting a huge amount of data in one of the most challenging settings. However, too much emphasis seems to be placed on the authors’ conclusions, especially taking into account some of the study’s limitations.

In 1989, a working group was constituted at the "Istituto di Elaborazione della Informazione" of the Italian National Research Council (IEI-CNR), within the framework of the National Antarctic Research Programme (PNRA), with the scope of providing ENEA with consulting services and technical support in information processing. The primary objective was to design and implement an integrated information system which would be based on the Antarctic Data Bank. Antarctic Data concerns research in Earth Sciences, Oceanography, Physics of the Atmosphere, Cosmophysics, Biology and Environmental studies and Medical Sciences. The South-Pole Directory is the first multidisciplinary Antarctic directory which is accessible on-line on international network, via ASTRA system and via ESA-PID system. The implementation of the Directory has required more than 1 year with several readjustments to the original objective; at present, the Directory provides the user with a description of the research and the available data as well as the procedures to obtain data. Data can also be requested directly from the individual research-groups.

Mediterranean Diet (Med Diet) is one of the healthiest dietary patterns. We aimed to verify the effects of weaning (i.e., the introduction of solid foods in infants previously fed only with milk) using adult foods typical of Med Diet on children eating habits, and on the microbiota composition. A randomized controlled clinical trial on 394 healthy infants randomized in a 1:1 ratio in a Med Diet group weaned with fresh; seasonal and tasty foods of Med Diet and control group predominantly weaned with industrial baby foods. The primary end point was the percentage of children showing a good adherence to Med Diet at 36 months. Secondary end points were mother’s changes in adherence to Med Diet and differences in children gut microbiota. At 36 months, children showing a good adherence to Med Diet were 59.3% in the Med Diet group and 34.3% in the control group (p < 0.001). An increase in adherence to the Med Diet was observed in the mothers of the Med Diet group children (p < 0.001). At 4 years of age children in the Med Diet group had a higher gut microbial diversity and a higher abundance of beneficial taxa. A Mediterranean weaning with adult food may become a strategy for early nutritional education, to develop a healthy microbiota, to prevent inflammatory chronic diseases and to ameliorate eating habits in children and their families.

ObjectivePatients with non-ischaemic dilated cardiomyopathy (NICM) may experience a normalisation in left ventricular ejection fraction (LVEF). Although this correlates with improved prognosis, it does not correspond to a normalisation in the risk of death during follow-up. Currently, there are no tools to risk stratify this population. We tested the hypothesis that absolute global longitudinal strain (aGLS) is associated with mortality in patients with NICM and recovered ejection fraction (LVEF).MethodsWe designed a retrospective, international, longitudinal cohort study enrolling patients with NICM with LVEF 50%). We studied the relationship between aGLS measured at the time of the first recording of a normalised LVEF and all-cause mortality during follow-up. We considered aGLS >18% as normal and aGLS ≥16% as of potential prognostic value.Results206 patients met inclusion criteria. Median age was 53.5 years (IQR 44.3–62.8) and 56.6% were males. LVEF at diagnosis was 32.0% (IQR 24.0–38.8). LVEF at the time of recovery was 55.0% (IQR 51.7–60.0). aGLS at the time of LVEF recovery was 13.6%±3.9%. 166 (80%) and 141 (68%) patients had aGLS ≤18% and 18%). In unadjusted Kaplan-Meier survival analysis, aGLS ConclusionsIn patients with NICM and normalised LVEF, an impaired aGLS at the time of LVEF recovery is frequent and associated with worse outcomes.

Acute dyspnea due to acute heart failure (AHF) is one of the most common reasons for admission to the Emergency Department (ED). The importance of lung ultrasound (LUS) examination in the diagnostic workup of AHF has been widely established. Limited anterior LUS examination for the diagnosis of AHF is controversial. This study compares the accuracy of LUS examination limited to the anterior or lateral lung zones for the diagnosis of AHF and their accuracy among patients with different levels of hypoxemia according to PO2/FiO2 ratio evaluation. We analyzed 170 patients admitted to the ED for acute dyspnea, who underwent multi-organ ultrasound examination of lung, heart and inferior vena cava for differential diagnosis. The thorax was examined following a simplified protocol that provides two scans at each side (anterior and lateral) to sample upper and lower lobes and the presence or the absence of interstitial syndrome (IS) was evaluated. The presence of anterior symmetric IS exhibited lower accuracy than lateral symmetric IS in the diagnosis of AHF in the whole population, but its diagnostic accuracy improves in sub-groups of patients with severe and critical hypoxemia.

Pulmonary hypertension (PH) is a disease characterized by progressive adverse remodeling of the distal pulmonary arteries, resulting in elevated pulmonary vascular resistance and load pressure on the right ventricle (RV), ultimately leading to RV failure. Invasive hemodynamic testing is the gold standard for diagnosing PH and guiding patient therapy. We hypothesized that lumped-parameter and biventricular finite-element (FE) modeling may lead to noninvasive predictions of both PH-related hemodynamic and biomechanical parameters that induce PH. We created patient-specific biventricular FE models that characterize the biomechanical response of the heart and coupled them with a lumped-parameter model that represents the systemic and pulmonic circulation. Simulations were calibrated by adjusting the pulmonary vascular resistance and myocardial contractility parameters through matching imaging data of ventricular chambers. Linear regression analysis demonstrated that the lumped-derived RV cardiac index (CI) was in good agreement with catheterization measurements collected from 10 patients with PH (R-2 = 0.82; p < 0.001). Biventricular FE analysis revealed a paradoxical leftward shift of the interventricular septum, and this correlated with invasive measurements of pulmonary vascular resistances (R = 0.70; p = 0.048) as found by Pearson's coefficient. A significant difference was noted for RV myocardial fiber stress in healthy control patients (4.5 +/- 0.7 kPa) compared with that of patients with PH at either rest (30.1 +/- 12.1 kPa; p = 0.005) or simulated exercise conditions (69.6 +/- 24.8 kPa; p < 0.001), thus suggesting adverse RV remodeling. This approach may become a useful and versatile tool for noninvasively assessing RV impairment induced by PH and realistically predicting ventricular mechanics and interactions for an improved management of patients with PH.

While thermal anisotropicity is a desirable materials property for many applications, including transverse thermoelectrics and thermal management in electronic devices, it remains elusive in practical natural compounds. In this work, we show how nanoporous materials with anisotropic pore lattices can be used as a platform for inducing strong heat transport directionality in isotropic materials. Using density functional theory and the phonon Boltzmann transport equation, we calculate the phonon-size effects and thermal conductivity of nanoporous silicon with different anisotropicpore lattices. Our calculations predict a strong directionality in the thermal conductivity, dictated by the difference in the pore-pore distances along the two Cartesian axes. As the space between pores along the direction of the applied temperature gradient represents the phonon bottleneck, an anisotropic pores lattice distortion induces directionality in heat transport. Using Fourier's law, we also compute diffusive heat transport for the same geometries obtaining significantly smaller anisotropicity, revealing the crucial role of phonon-size effects in tuning thermal transport directionality. Besides enhancing our understanding of nanoscale heat transport, our results demonstrate the promise of nanoporous materials for modulating anisotropy in thermal conductivity.