Realistic modelling of water/solid interfaces from ab Initio molecular dynamics

Water/solid interfaces are of utmost importance to a number of technological processes. Theoretical studies, based on ab initio approaches are suitable to unveil processes occurring at water/solid interfaces and can therefore be instrumental to delineate guidelines to improve the efficiency of these processes. In this thesis we study several systems of current interest using ab initio methods based on density functional theory (DFT). By going often beyond the use of standard DFT methods and approximations we have provided insights into processes occurring at water/solid interfaces under ambient conditions and in non stoichiometric conditions. Specifically, we will investigate the interactions between water and ZnO, an important metal-oxide especially used in industry to produce methanol. One of the most mportant results of this study is that proton hopping is dramatically enhanced under wet conditions compared to ideal ultra-high vacuum conditions. Also, we will compute the friction between liquid water in contact with 2-D layered materials, and delineate the guidelines on how to alter the friction coe cient in membranes used for desalination or osmotic power harvesting. Finally, in collaboration with Geoff Thornton's group we have investigated the role of defects on the surface chemistry of the rutile TiO2(110), which is the model oxide surface used in photocatalysis applications. On the whole, in this work we have used ab initio methods to reduce the gap between the ultra-high vacuum-style studies of adsorption on perfect defect-free surfaces and the complex behaviour of liquid/solid interfaces under technologically relevant conditions

Ubiquitous Internet in an integrated satellite-terrestrial environment: The SUITED solution

yesThe current Internet architecture appears to not be particularly suited to addressing the emerging needs of new classes of users who wish to gain access to multimedia services made available by ISPs, regardless of their location, while in motion and with a guaranteed level of quality. One of the main objectives of so-called nextgeneration systems is to overcome the limitations of today¿s available Internet by adopting an approach based on the integration of different mobile and fixed networks. The SUITED project moves in this direction since it aims at contributing to the design and deployment of the global mobile broadband system (GMBS), a unique satellite/terrestrial infrastructure ensuring nomadic users access to Internet services with a negotiated QoS. A description of the main features of the GMBS architecture, characterized by the integration of a multisegment access network with a federated ISP network is given in this article. The GMBS multimode terminal is schematically described, and an overview of the so-called QoS-aware mobility management scheme, devised for such a heterogeneous scenario,is provided

Beam diagnostics for charge and position measurements in ELI-NP GBS

The advanced source of Gamma-ray photons to be built in Bucharest (Romania), as part of the ELI-NP European Research Infrastructure, will generate photons by Compton back-scattering in the collision between a multi-bunch electron beam and a high intensity recirculated laser pulse. An S-Band photoinjector and the following C-band Linac at a maximum energy of 720MeV, under construction by an European consortium (EurogammaS) led by INFN, will operate at 100Hz repetition rate with trains of 32 electron bunches, separated by 16ns and a 250pC nominal charge. The different BPMs and current transformers used to measure transverse beam position and charge along the LINAC are described. Design criteria, production status and bench test results of the charge and position pickups are reported in the paper, together with the related data acquisition systems

Evaluation of cavitation erosion resistance of Al-Si casting alloys: effect of eutectic and intermetallic phases

In the present paper, the influence of eutectic and intermetallic phases on cavitation resistance of Al-Si alloys was studied. In fact, Al-Si alloys are commonly used for the production of components, such as cylinders, pistons, pumps, valves and combustion chambers, which in service may incur in cavitation phenomenon. Samples of AlSi3, AlSi9 and AlSi9CuFe were characterized from the microstructural point of view. Hardness measurements were also performed. Subsequently, cavitation tests were carried out according to ASTM G32 standard and the erosion mechanism was examined by scanning electron microscope. It was found the both eutectic and intermetallic phases enhance cavitation resistance, expressed in terms of mass loss. Particularly, intermetallic particles with complex morphologies provide a positive contribution, exceeding that of other microstructural features, as grain size. The effect of T6 heat treatment was also evaluated. It was confirmed that the precipitation of fine strengthening particles in the Al matrix successfully hinders the movement of dislocations, resulting in a longer incubation stage and a lower mass loss for heat-treated samples in comparison with as-cast ones. Finally, the relationship between cavitation resistance and material hardness was investigated

Structure of a model TiO2 photocatalytic interface

The interaction of water with TiO2 is crucial to many of its practical applications, including photocatalytic water splitting. Following the first demonstration of this phenomenon 40 years ago there have been numerous studies of the rutile single-crystal TiO2(110) interface with water. This has provided an atomic-level understanding of the water-TiO2 interaction. However, nearly all of the previous studies of water/TiO2 interfaces involve water in the vapour phase. Here, we explore the interfacial structure between liquid water and a rutile TiO2(110) surface pre-characterized at the atomic level. Scanning tunnelling microscopy and surface X-ray diffraction are used to determine the structure, which is comprised of an ordered array of hydroxyl molecules with molecular water in the second layer. Static and dynamic density functional theory calculations suggest that a possible mechanism for formation of the hydroxyl overlayer involves the mixed adsorption of O2 and H2O on a partially defected surface. The quantitative structural properties derived here provide a basis with which to explore the atomistic properties and hence mechanisms involved in TiO2 photocatalysis

Clinical Effects of Xanthine Oxidase Inhibitors in Hyperuricemic Patients.

open5noThis review aims to critically present the available clinical evidence supporting the treatment of chronic hyperuricemia with xanthine oxidase inhibitors. For this reason, the studies published on uric acid (UA)-lowering drugs in the English language from 2000 to August 2019 have been carefully reviewed. The terms "serum uric acid," "xanthine oxidase," "allopurinol," "febuxostat," and "topiroxostat" were incorporated into an electronic search strategy, alone and in combinations, in both MEDLINE (National Library of Medicine, Bethesda, MD) and the Cochrane Register of Controlled Trials (The Cochrane Collaboration, Oxford, UK). Even if new urate-lowering drugs seem of particular efficacy for acute treatment of refractory hyperuricemia, their use is supported by relatively small clinical evidence. On the contrary, large long-term clinical trials have demonstrated that xanthine oxidase inhibitors (XOIs, namely, allopurinol and febuxostat) are effective, safe, and relatively well-tolerated in most of the patients. They have mainly been tested in the elderly, in patients affected by chronic diseases such as heart failure and cancer, and in patients taking a large number of drugs, confirming their safety profile. Recent data also show that they could exert some positive effects on vascular health, renal function, and glucose metabolism. Their cost is also low. In conclusion, XOIs remain the first choice of UA-lowering drug for chronic treatment.openCicero AFG, Fogacci F, Cincione RI, Tocci G, Borghi C.Cicero AFG, Fogacci F, Cincione RI, Tocci G, Borghi C

Morphological characteristics of "Monterufoli horse"

Monterufoli horse is a local endangered breed of the Tuscany and derives from the omonym area in province of Pisa. This horse derives from local wild and extinct equines and has Maremmano, Tolfetano and Oriental ancestors. The mean and the standard deviation of biometric characters, and the absolut and percentage frequency of morphological characteristics were calculated. The measures of the adult females were estimated by ANOVA considering three different class of age. The average sizes were: height at withers of 135.4±6.3 and 129.2±5.9, thorax circumference of 166.4±8.3 and 163.4±8.9, frontshank circumference of 17.7±1.5 and 17.5±0.9, for males and females, respectively. All the observed horses presented dark coat. Monterufoli horses showed the physical characteristics of local extinct ancestors (Selvena pony), but also the characteristics of other breeds that contributed to improve the local population. This horse, which was once used in agriculture and for light draught, is now involved for saddle use

Friction of water on graphene and hexagonal boron nitride from ab initio methods: very different slippage despite very similar interface structures

Friction is one of the main sources of dissipation at liquid water/solid interfaces. Despite recent progress, a detailed understanding of water/solid friction in connection with the structure and energetics of the solid surface is lacking. Here, we show for the first time that ab initio molecular dynamics can be used to unravel the connection between the structure of nanoscale water and friction for liquid water in contact with graphene and with hexagonal boron nitride. We find that although the interface presents a very similar structure between the two sheets, the friction coefficient on boron nitride is ≈ 3 times larger than that on graphene. This comes about because of the greater corrugation of the energy landscape on boron nitride arising from specific electronic structure effects. We discuss how a subtle dependence of the friction on the atomistic details of a surface, which is not related to its wetting properties, may have a significant impact on the transport of water at the nanoscale, with implications for the development of membranes for desalination and for osmotic power harvesting

Real-life appraisal on blood pressure targets achievement in adult outpatients at high cardiovascular risk

Background and aim: Although hypertension guidelines highlight the benefits of achieving the recommended blood pressure (BP) targets, hypertension control rate is still insufficient, mostly in high or very high cardiovascular (CV) risk patients. Thus, we aimed to estimate BP control in a cohort of patients at high CV risk in both primary and secondary prevention. Methods and results: A single-center, cross-sectional study was conducted by extracting data from a medical database of adult outpatients aged 40–75 years, who were referred to our Hypertension Unit, Rome (IT), for hypertension assessment. Office BP treatment targets were defined according to 2018 ESC/ESH guidelines as: a)<130/80 mmHg in individuals aged 40–65 years; b)<140/80 mmHg in subjects aged >65 years. Primary prevention patients with SCORE <5% were considered to be at low-intermediate risk, whilst individuals with SCORE ≥5% or patients with comorbidities were defined to be at very high risk. Among 6354 patients (47.2% female, age 58.4 ± 9.6 years), 4164 (65.5%) were in primary prevention with low-intermediate CV risk, 1831 (28.8%) in primary prevention with high-very high CV risk and 359 (5.6%) in secondary prevention. In treated hypertensive outpatients, uncontrolled hypertension rate was significantly higher in high risk primary prevention than in low risk primary prevention and secondary prevention patients (18.4% vs 24.4% vs. 12.5%, respectively; P < 0.001). In high risk primary prevention diabetic patients only 10% achieved the recommended BP targets. Conclusions: Our data confirmed unsatisfactory BP control among high-risk patients, both in primary and secondary prevention, and suggest the need for a more stringent BP control policies in these patients

morphological characteristics of amiata donkey reared in tuscany

In this work were studied morphological characteristics and biometric parameters of the Amiata donkey. The Amiata donkey is a local endangered breed and derives from the homonym mountain in Tuscany. This donkey, which was used, over the past, like pack animal in farms and in mines, is now involved in milk production, onotherapy and trekking. The averages and the standard deviations of the biometric parameters and the frequency of the morphological characters of foals, adult females and stallions were calculated. The measures of the adult females were estimated by ANOVA considering three different classes of age: 3-4, 5-6, over6yearsold. 3-4, 5-6, over 6 years old.. The average sizes were: height at withers of 129.8±4.7and125.8±5.6cm,thoraxcircumferenceof145.6±7.8and145.0±7.8cm, 129.8±4.7 and125.8±5.6cm,thoraxcircumferenceof145.6±7.8and145.0±7.8cm, and 125.8±5.6cm,thoraxcircumferenceof145.6±7.8and145.0±7.8cm, 125.8±5.6 cm,thoraxcircumferenceof145.6±7.8and145.0±7.8cm, , thorax circumference of 145.6±7.8and145.0±7.8cm, 145.6±7.8and145.0±7.8cm, and 145.0±7.8cm, 145.0±7.8 cm,, front shank circumference of 18.3±0.8and16.9±1.5cm,forstallionsandadultfemalesrespectively.All 18.3±0.8 and16.9±1.5cm,forstallionsandadultfemalesrespectively.All and 16.9±1.5cm,forstallionsandadultfemalesrespectively.All 16.9±1.5 cm,forstallionsandadultfemalesrespectively.All , for stallions and adult females respectively. All the observed donkeys presented dark grey coat with the shoulder stripe. The zoometric indices of the adult females did not differ between the classes and showed that the somatic adult proportions had al- ready reached in 3-4 years old donkeys. This breed showed the features of the ancestors: the shoulder stripe of the Equus asinus africanus and the legs stripes of the Equus asinus somaliensis