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Disordered optical media are an emerging class of materials that can strongly scatter light. These materials are useful to investigate light transport phenomena and for applications in imaging, sensing and energy storage. While coherent light can be generated using such materials, its directional emission is typically hampered by their strong scattering nature. Here, the authors directly image Rayleigh scattering, photoluminescence and weakly localized Raman light from a random network of silicon nanowires via real‐space microscopy and Fourier imaging. Direct imaging enables us to gain insight on the light transport mechanisms in the random material, to visualize its weak localization length and to demonstrate out‐of‐plane beaming of the scattered coherent Raman light. The direct visualization of coherent light beaming in such random networks of silicon nanowires offers novel opportunities for fundamental studies of light propagation in disordered media. It also opens venues for the development of next generation optical devices based on disordered structures, such as sensors, light sources, and optical switches. [ABSTRACT FROM AUTHOR]

Scientific disciplines often result as difficult and not attractive subjects for the young generations. In recent years, the experiential didactic has shown to be a much more functional educative approach, both to encourage interest in science and to facilitate the learning of difficult concepts. In this paper a new highly effective method of education is proposed, in which the schooler becomes himself an active protagonist of the studied physics phenomenon, where the body and emotive sensations encouraged the spheres of learning. We will present an innovative project, the "Physics Adventure Lab", involving 10-14 years old students based on this new model of teaching. [ABSTRACT FROM AUTHOR]

Both experiments with deeply penetrating femtosecond laser pulses and theoretical analysis demonstrate that at low laser fluences on (111) and (111) surfaces of n-doped GaAs semiconductors the hypersound generation mechanism is the inverse piezoelectric effect. The transient electric field causing the inverse piezoelectric effect is due to the spatial separation in the built-in near-surface electric field of the electrons and holes photoexcited directly in the depletion region and also of those photoexcited outside the depletion region and diffusing toward it. However, with increasing laser fluence the amplitude of the acoustic signal generated by laser-induced transient electric fields saturates and the hypersound generation through electron-hole-phonon deformation potential mechanism becomes predominant. The peculiar dependencies of the hypersound amplitude and phase on pump laser fluence reveal the transition between the two physical mechanisms of optoacoustic conversion. The phase of the acoustic signal contains information on the temporal dynamics of the screening of the built-in electric field. [ABSTRACT FROM AUTHOR]

In this study, we demonstrate the preparation of laser-cum KOH-activated porous carbon with tunable ionic states, unique surface chemistry, and physical texture from renewable and environmentally friendly precursors (waste cardboard boxes). The adsorption performance of the engineered adsorbents is examined on the adsorption of methyl blue (MB, anionic) and methylene blue (MeB, cationic). The adsorption mechanism was determined using detailed batch adsorption, and the MB was adsorbed via the formation of ternary complexes, whereas the MeB was adsorbed through cation-π interaction. Furthermore, the non-activated laser-induced carbon (LIC100) and the KOH-activated carbon (KAC(L)) exhibit superior dye adsorption capacities of 9610 (MB) and 1882 mg g−1 (MeB), respectively. To the best of our knowledge, this is the highest ever reported at dye removal in the field of adsorptive dye removal. Langmuir isotherm model and pseudo-second-order are fitted well for both MB and MeB adsorption. Lastly, the carbons generated through this modern technique can be remodeled into a more secure device to obtain clean and microorganism-free water. This study showed the potential of laser-induced carbonization of KOH-activated substrate and provided unique insights into future development for universal dye adsorption and other possible applications. [Display omitted] • Successful synthesis of waste-derived carbon via laser-induced carbonization. • Utilization of cardboard waste for environmental remediation. • Salt bridge and cation-π adsorption mechanism. • Superior adsorption capacity of 9610 (MB) and 1882 mg g−1 (MeB), respectively. • Ultrafast dye removal performance of LIC100 and KAC(L). [ABSTRACT FROM AUTHOR]

The TiO2/kaolinite material—a filler for construction materials with the function of passive degradation of household organic pollutants—has been synthesized and its properties have been examined. Synthesis of the material has been performed under varied conditions: the amount of the reactive mixture and temperature of thermal treatment have been altered. Thereafter, the effect of the synthesis conditions on chemical composition, surface morphology, phase composition, adsorption parameters, and changes in the adsorption activity has been determined at irradiation by UV and visible light. [ABSTRACT FROM AUTHOR]

Abstract: Archaeological excavations, undertaken since 2004 for the construction of the new Naples subway, have unearthed the harbor basin of the Greco–Roman town of Parthenope–Neapolis, furnishing scientists with the opportunity to recover abundant archaeological remains and a thick succession of diverse infill sediments. The latter underwent sedimentological, paleontological, and volcanological analyses. Compositional data analysis, applied to all three data sets, highlighted three main paleoenvironmental changes in the harbor basin from the Augustan Age up to the 6th century A.D. The beginning of harbor activity is recorded during the 3rd century B.C. when sedimentation was interrupted by intensive dredging of the sea‐bottom. The impact of the A.D. 79 Vesuvius eruption, recorded for the first time in the Neapolitan territory, led to a reduction in Posidonia meadows and to an ensuing phase of more restricted water circulation and pollution. At the beginning of the 5th century A.D., an open lagoon environment was established, attesting to coastal progradation. The final closure of this part of the bay occurred at the end of the 5th to the beginning of the 6th century A.D., due to increased alluvial input linked to both natural and anthropogenic causes. [ABSTRACT FROM AUTHOR]

Time-domain Brillouin scattering is an all-optical experimental technique based on ultrafast lasers applied for generation and detection of coherent acoustic pulses on time durations of picoseconds and length scales of nanometers. In transparent materials, scattering of the probe laser beam by the coherent phonons permits imaging of sample inhomogeneity. The transient optical reflectivity of the sample recorded by the probe beam as the acoustic nanopulse propagates in space contains information on the acoustical, optical, and acousto-optical parameters of the material under study. The experimental method is based on a heterodyning where weak light pulses scattered by the coherent acoustic phonons interfere at the photodetector with probe light pulses of significantly higher amplitude reflected from various interfaces of the sample. The time-domain Brillouin scattering imaging is based on Brillouin scattering and has the potential to provide all the information that researchers in materials science, physics, chemistry, biology, etc., get with classic frequency-domain Brillouin scattering of light. It can be viewed as a replacement for Brillouin scattering and Brillouin microscopy in all investigations where nanoscale spatial resolution is either required or advantageous. Here, we review applications of time-domain Brillouin scattering for imaging of nanoporous films, ion-implanted semiconductors and dielectrics, texture in polycrystalline materials and inside vegetable and animal cells, and for monitoring the transformation of nanosound caused by nonlinearity and focusing. We also discuss the perspectives and the challenges for the future. [ABSTRACT FROM AUTHOR]

The landscape evolution of the Sant’Eufemia Plain (Calabria, Italy) in the last 8300 years was reconstructed through integration of pollen data and archaeological evidence within a well-defined paleoenvironmental and chronostratigraphical framework. Pollen analysis of a 24-m core showed that a dense floodplain forest characterized the landscape from ca. 8300 up to ca. 2300 yr cal BP, when human impact becomes evident through intense deforestation, cultivation and fires. Due to the high density of the forest canopy in the plain, few signs of human presence are recorded by pollen in prehistoric and protohistoric periods despite the occurrence of settlements from the Neolithic to the Iron Age. In concurrence with the reduction of wet environments in the plain and the surrounding foothills, major urban centers and villas developed during the Graeco-Roman period, entailing considerable environmental impact. Clear signs of deforestation, recorded through a general reduction of tree taxa, were connected to timber production and trade during the Roman period, as also attested by historical sources. Intensive olive cultivation started in the Early Medieval period, in agreement with other data from central and southern Italy, suggesting that olive oil consumption during the Roman period was not connected to large-scale local production. The Holocene history of this landscape shows that the location of settlements from the Neolithic onward was strongly influenced by the environment, which led people to select more stable, well-drained areas, such as relicts of inactive depositional landforms within or around the plain. [ABSTRACT FROM AUTHOR]

A multi-proxy approach has been adopted to reconstruct the Holocene history of the St. Eufemia Plain (western Calabria, Italy) and to discern the influence that sea level rise and tectonics exerted in its evolution. Sedimentological, paleoecological and palynological data have been obtained from a 24-m long core, mostly made of pelitic back-barrier sediments, chronologically constrained by twelve AMS C dates. Radiocarbon ages of lagoon samples have been corrected by taking into account the influence of both the marine and hardwater effect on the reservoir age. The new data have been integrated with those of pre-existing stratigraphies in order to better characterize the overall sedimentary architecture of the plain. In the early Holocene (from ca. 8300 to ca. 6900 yr. cal BP), eustasy largely prevailed on the tectonic uplift, causing coastline ingression and aggradation. From ca. 6900 to ca. 2800 yr. cal BP, coastline progradation and aggradation were driven by high detrital inputs and slowdown of sea level rise, during a phase characterized by a general weak subsidence. From ca. 2800 to ca. 1400 yr. cal BP, higher rates of subsidence favored the establishment of marsh and flooded alluvial plain environments in the back-barrier domain. After ca. 1400 yr. cal BP, a substantial stability characterized the St. Eufemia Plain. [ABSTRACT FROM AUTHOR]

According to the WEEE European directives, efforts must be undertaken to reuse or safely dispose liquid crystal displays (LCD) waste, however no practical process was reported yet, although it is possible to recover glass, plastic and precious metals, in particular indium. Indium is one of the elements included by the European Commission in the list of 20 raw materials critical for economic importance and high supply risk (European Commission, https://ec.europa.eu/ growth/tools-databases/eip-raw-materials/en/system/files/ged/ 79%20report-b_en.pdf [1]). The work aims to valorize LCD scraps after indium recovery with low cost applications both economically and environmentally speaking. Applications have been explored by many researchers, although most focused only on the use of glass powder waste LCD to design concrete. This work deals the use of LCD scraps as it is after cross-current leaching of indium with H2SO4. The experimental work consists of scraps characterization, washing procedure optimization to remove residual acid, mortar production, performance testing, and life cycle assessment (LCA). The results show that LCD scraps exhibit little or no pozzolanic activity. This delay on reactivity can be ascribed to organic residues that prevent the pozzolanic reaction and/or to a lower fineness than that typical of binders or fillers. For this reason the actual investigation focuses to exploit the waste as partial replacement of traditional aggregates. [ABSTRACT FROM AUTHOR]

Recycled materials in the building industry represent an attractive alternative to the consumption of natural resources. The paper shows results obtained by adding electric arc furnace slag (EAFs) as partial replacement of natural aggregates in concrete production. EAFs determines a significant increase in the compressive strength of concrete while it does not seem to affect the bending strength and drying shrinkage of cement mixtures. The concrete durability was approached by a careful chemical analysis and microstructural investigation of EAFs. The tendency to deteriorate seems negligible due to a low presence of amorphous and expansive compounds leading to an increase in volume. Moreover, the metals released, compared with the national legislation requirements, meet environmental standards. [ABSTRACT FROM AUTHOR]

We report the investigation of the generation and detection of GHz coherent acoustic phonons in plasmonic gold nanoparticle superlattices (NPSs). The experiments have been performed with an optical femtosecond pump-probe scheme across the optical plasmon resonance of the superlattice. Our experiments allow us to estimate first the fundamental mechanical parameters such as the collective elastic response (sound velocity) of the NPS and the nanocontact elastic stiffness. Furthermore, it appears that the light-induced coherent acoustic-phonon pulse has a typical in-depth spatial extension of about 45 nm which is roughly four times the optical skin depth in gold. The modeling of the transient optical reflectivity indicates that the mechanism of phonons generation is achieved through ultrafast heating of the NPS assisted by light excitation of the volume plasmon polariton. Based on these results, we demonstrate that it is possible to map the photon-electron-phonon interaction in subwavelength nanostructures which, in particular, provides insights on the fundamental properties of these nanometamaterials. [ABSTRACT FROM AUTHOR]

A physical approach to synthesize fractal surfaces for a reliable and controllable use within remote-sensing applications is presented in this paper. In particular, the physical criteria to determine the minimum number of tones of the Weierstrass–Mandelbrot (WM) function needed to adequately synthesize realizations of fractional Brownian motion (fBm) processes are analytically derived. The presented rationale relies on considering, in an appropriate range of scales, the WM function as a spectral sampling of the fBm process, and linking the number of sampling functions to the width of the scale range and to the sampling rate; hence, it is shown how to set the lower and the upper scales according to a given remote-sensing problem. In this paper, the condition for determining the WM wavenumber sampling rate is analytically derived. The method is also applied to the efficient simulation of the synthetic aperture radar signal scattered by natural surfaces. [ABSTRACT FROM PUBLISHER]

In this review we address the microscopic mechanisms that are involved in the photogeneration processes of GHz–THz coherent acoustic phonons (CAP) induced by an ultrafast laser pulse. Understanding and describing the underlying physics is necessary indeed for improving the future sources of coherent acoustic phonons useful for the non-destructive testing optoacoustic techniques. Getting more physical insights on these processes also opens new perspectives for the emerging field of the opto-mechanics where lattice motions (surface and/or interfaces ultrafast displacements, nanostructures resonances) are controlled by light. We will then remind the basics of electron–phonon and photon-phonon couplings by discussing the deformation potential mechanism, the thermoelasticity, the inverse piezoelectric effect and the electrostriction in condensed matter. Metals, semiconductors and oxide materials will be discussed. The contribution of all these mechanisms in the photogeneration process of sound will be illustrated over several examples coming from the rich literature. [ABSTRACT FROM AUTHOR]

Coherent GHz acoustic phonon dynamics in a tubular nanoporous alumina film is studied with picosecond acoustic methods. This study has allowed the determination of the out-of-plane sound velocity and the effective optical index through a time-resolved Brillouin analysis. Several acoustic eigenmodes of the tubular nanoporous alumina film were detected. These GHz eigenmodes exhibit unusual frequency-dependent long lifetimes. Their strong confinement has been explained by the presence of a thin alumina layer at the film/substrate interface which plays the role of an acoustic mirror. Finally, we show that the optical detection process of these long-living eigenmodes can be either enhanced or reduced to zero following a selection rule. In particular, we demonstrate that detection configurations exist where the coherent acoustic phonon and probe light sensitivity functions are orthogonal, leading to cancellation of the photoelastic light scattering mechanism. This has never been reported so far in the physics of the interaction of coherent acoustic phonons with light. [ABSTRACT FROM AUTHOR]

Paper mill sludge is often incinerated for heat recovery and volume reduction. In Italy, about 600,000 t of paper mill sludge is produced yearly. About 6 kg of sludge is produced per ton of paper produced. The paper mill sludge is recovered from a primary mechanical separation process. When it is combusted as a single fuel source, it produces paper mill sludge ash (PA). In this project, PA was studied to evaluate its use as a supplementary cementitious material in mortars and concrete manufacturing. On the basis of the data collected, it was concluded that PA, if used to replace up to 10% of the portland cement, shows a positive effect on the mechanical performance of mortars. On the other hand, because of its high fineness and consequently high water absorption, it required a higher amount of water. It was concluded that the use of PA should not be higher than 10% by weight of the cement replaced, unless mortar mixtures are judiciously proportioned. [ABSTRACT FROM AUTHOR]

The objective of this study was to assess heavy metals accumulation and equilibrium phenomena in river sediment, in relation to water quality, and to assess metals lability, analysing whether and how easily heavy metals are available to generic biota. The diffuse gradient in thin film technique was used to assess the effective concentration (CE). The solid-liquid distribution coefficient of the metals labile pool (Kdl) was calculated to include it in risk analysis within a more realistic frame. The Esino River was chosen for the case study. The results confirmed the need to determine Kd experimentally; values of Kd taken from the literature resulted in errors of some orders of magnitude. Metals speciation, environmental conditions, the type and texture of the sediment, features of the water, organic fraction, pH and salinity can all influence the outcome. The results showed that the two main parameters on which Kd depends are chemical oxygen demand and specific surface area. CE, which takes into account the contribution of both the water and the labile fraction in the sediment, is a key parameter and may be 5-100×the concentration in the pore water. [ABSTRACT FROM AUTHOR]

Fractal geometry is widely accepted as an efficient theory for the characterization of natural surfaces; the opportunity of describing irregularity of natural surfaces in terms of few fractal parameters makes its use in direct and inverse electromagnetic (EM) scattering theories highly desirable. In this paper, we present an innovative procedure for manufacturing fractal surfaces and for measuring their scattering properties. A cardboard-aluminum fractal surface was built as a representation of a Weiestrass--Mandelbrot fractal process; the EM field scattered from it was measured in an anechoic chamber. A monostatic radarlike configuration was employed. Measurement results were compared to Kirchhoff approximation and small perturbation method closed-form results that were analytically obtained by employing the fractional Brownian motion to model the surface shape. Matching and discrepancies between theories and measurements are then discussed. Finally, fractal and classical surface models are compared as far as their use in the EM scattering is concerned. [ABSTRACT FROM AUTHOR]

The objective of this study is to provide an insight into the techniques for measuring the lability of heavy metals in solid-phase pool of soils in order to assess the environmental risk arising from pollution. The technique of diffusive gradients in thin films (DGT) and a sequential extraction procedure were used to quantify the labile pools of Cu, Fe, Mn and Ni. These results were compared to metal concentrations in groundwater, measured directly using the in situ piezometers, and to the total concentration of metal in the soils. High concentrations of metal in the directly analysed soil solution compared to DGT measurement were attributed to the presence of colloidal metal. The use of DGT allowed only to calculate leaching parameters of the free ions and labile fractions of the metals. For this reason DGT technique needs preliminary investigation on metal speciation in soil solution before its application as a good tool in the characterization procedure of contaminated sites. [Copyright &y& Elsevier]

Fractal geometry provides reliable models to describe geometrical properties of natural surfaces. Therefore, their use in the electromagnetic scattering methods deserves careful research. In order to have complete insight into the phenomenon, a measurement campaign on a fractal surface in a controlled environment is a key step. In this paper, we propose a technique for building a fractal surface that can be used for electromagnetic scattering evaluation purposes. The surface characteristics are imposed by computer synthesizing a bandlimited Weierstrass-Mandelbrot function, whose actual shape is constructed by means of a cheap innovative technique: the synthesized surface is made from cardboard covered with aluminum foil, which gives a conducting surface and creates the micro-scale conditions, useful to represent manufacturing errors. Statistics of the overall surface shape are then measured, analyzed and compared with the imposed ones, providing and verifying the rationale for a fully controlled surface to be applied in any kind of experiment on natural surfaces. [ABSTRACT FROM AUTHOR]

Proteinase 3 (PR3), also called myeloblastin, is involved in the control of myeloid cell growth, but the underlying molecular mechanisms have not been elucidated. In U937/PR3, stably transfected with PRCRSV/PR3 to overexpress PR3, PMA-induced p21 expression was significantly decreased as compared with control U937, and this phenomenon was reversed in the presence of the serine proteinase inhibitor, pefabloc. Conversely, when PR3 was inactivated by small interfering RNA, p21 protein was increased, and PMA-induced monocytic differentiation was potentiated. Mass spectrometry analysis identified Ala45 as the primary cleavage site on p21, and the recombinant mutated p21A45R, generated by site-directed mutagenesis and expressed in Escherichia coli, was resistant to in vitro PR3 cleavage. The U937 cells were then stably transfected with either PRCRSV/p21 or PRCRSV/p21A45R, to ectopically express wild type p21 or PR3-resistant p21, respectively. In U937/p2L1A45R treated with PS-341, a selective proteasome inhibitor, a significant decrease in the S phase and a blockade in the G0–G1 phase of cell cycle were observed when compared with U937/p21 or control U937. This suggested that both PR3 and the proteasome are efficiently involved in the proteolytic regulation of p21 expression in myeloid cells. Moreover, PMA-induced p21 expression was more pronounced in U937/p21A45R compared with U937/p21 and was concomitant with the morphological features of early differentiation. Our data demonstrated that p21 is one specific target of PR3 and that PR3-mediated p21 cleavage prevents monocytic differentiation. [ABSTRACT FROM AUTHOR]

Abstract: A pump–probe optical spectroscopy technique was used to study the time-resolved reflectivity in the range 0–160ps of the metal–insulator transition compound NdNiO3. It enables, for the first time, the direct real-time observation of the non-equilibrium electron dynamics in the insulating and in the metallic state of that compound and the acoustical response. Strong change of the transient reflectivity is observed as a function of temperature. First of all, the magnitude of the fast component of transient reflectivity (, 0–3ps) increases drastically when . Moreover, the relaxation time of the fast-component increases when the insulating state is reached. Vanishing of the acoustic echo magnitude with decreasing temperature is also reported. All these singular properties could be connected to the gap opening mechanism below MIT. [Copyright &y& Elsevier]

Abstract: X-ray and neutron powder diffraction studies of UO2 were performed under controlled oxygen partial pressure between room temperature and 1673K. More than 40 neutron diffraction patterns were recorded. The thermal expansion coefficient of UO2 and the temperature dependence of Debye–Waller factors for oxygen and uranium atoms were determined. The dependence of Debye–Waller factors as a function of temperature is linear and the thermal expansion coefficient follows the classical Debye regime within the temperature range 300–1000K. Above 1200K, a departure from this quasi-harmonic behavior is clearly observed. Both an abnormal increase of the thermal expansion and of the oxygen sublattice disorder are evidenced. The departure of the lattice parameter from a linear thermal variation is found to be thermally activated with an effective activation energy close to 1eV, very similar to the activation energy already found for the electrical conductivity. This new result suggests that polarons may affect the mean lattice parameter. A new thermodynamic model is then proposed to explain the heat capacity thermal variation by only three contributions: harmonic phonons, thermal expansion and polarons. [Copyright &y& Elsevier]

The electricity conductivity and thermoelectric power of an uranium dioxide single crystal were measured between 908 and 1697 K and for PO2 included between 10-24 atm and the boundary UO2+x/U4O9. For T<1273K and near stoichiometry, the electrical conductivity versus PO2 shows a plateau characteristic of an extrinsic regime. For T ≥ 1273 K, the conductivity exhibits a minimum. The Seedbeck coefficient &Qmacr;UO2 also exhibits a behavior change when the temperature is increased. For T<1200 K, &Qmacr;UO2 remains positive whatever the values of PO2. For T> 1200 K, &Qmacr; UO2 changes from negative to positive values who PO2 increases. This set of results shows that the stoichiometric oxide presents a p extrinsic to intrinsic trasition near 1273 K. At T ≤ 1273 K, the extrinsic conductivity values versus temperature confirm that the mobility of the holes occurs by a small polaron process, with an activation energy of 0.17 eV. At T>1273 K, the electrical conductivity minima are characteristic of a p→n transition. A band gap energy of 2.0 eV has been calculated from the temperature dependence of these conductivity minima values. Furthermore, this set of results has allowed us to determine the relative oxygen partial molar free energy of stoichiometric UO2. [ABSTRACT FROM AUTHOR]

The temperature variation of UV–VIS–NIR optical spectra of UO2 have been investigated from room temperature up to 1173 K with careful in situ oxygen partial pressure control. The deduced optical absorption edge exhibits a strong temperature dependence. Its value decreases from ∼2 eV at room temperature to ∼0.8 eV at 1173 K. Such thermal behaviour is interpreted as the consequence of the existence of a strong electron–phonon coupling (small polaron). In the temperature range 300–1173 K, the model yields a hopping radius of ∼2 Å and a polaron self-energy of Ep=-0.38 eV. [Copyright &y& Elsevier]

The chemical diffusion coefficient of UO2+x was determined from electrical conductivity measurements performed during transient state, for departure from stoichiometry in the range 0 and for temperatures varying from 973 to 1673 K. It was found that D is a decreasing function of the departure from stoichiometry, while the oxygen diffusion coefficient reported in literature is an increasing function in the same range of departure from stoichiometry. For x<0.07, this behavior was attributed to the presence of the singly ionized (2:2:2)′ Willis defects evidenced by electrical conductivity measurements. The enthalpy of formation of these clusters amounts to ΔHf=−1.7±0.6 eV. For x&ges;0.07, the decreasing function of D with x can be explained either by Willis defects α time ionized or more complex defect aggregates or via a dynamic exchange between mobile small defects and larger clusters or domains. [Copyright &y& Elsevier]

Background Mayotte is a French overseas territory with significant socio-economic and health challenges. This study updates the prevalence of hypertension in Mayotte to estimate the awareness, treatment and control of this disease and identify any associated factors. Methods Data were taken from the cross-sectional Unono Wa Maore survey conducted in Mayotte in 2019. Analyses were based on the adult population aged 18–69 years who underwent a clinical examination with at least two blood pressure measurements (n  = 2620). Results In 2019, the prevalence of hypertension was estimated at 38.4% (36.1–40.7%) in the Mayotte population aged 18–69 years. The prevalence was similar in men (38.5%) and women (38.3%; P  = 0.95). The prevalence of certain risk factors was high, with 75% of hypertensives being overweight or obese, 13% reporting diabetes and 69% being occupationally inactive. Among the hypertensives, 48% was aware of their diagnosis, with women more likely to be aware than men (P  < 0.0001). Of those who were aware, 45% were treated pharmacologically and 49% reported engaging in physical activity to lower their blood pressure. The control rate was 30.2% among pharmacologically treated hypertensives. Overall, 80% of hypertensive patients had too high blood pressure during the survey's clinical examination. Conclusion The prevalence of hypertension remains high in Mayotte, where certain risk factors like obesity are particularly common in the population. Awareness, treatment and control remain insufficient. Primary prevention measures, access to a healthy food, and screening and treatment of hypertension should be encouraged by targeting the most affected populations. [ABSTRACT FROM AUTHOR]

Using femtosecond laser pulses, coherent GHz acoustic phonons are efficiently photogenerated and photodetected in BiFeO3 (BFO) multiferroic single crystal. Due to the crystal lattice symmetry, longitudinal as well as two transverse acoustic modes are generated and detected, and the corresponding sound velocities are determined. This provides the opportunity to experimentally evaluate the elastic coefficients of the multiferroic compound BiFeO3 that have been estimated so far only through ab initio calculations. The knowledge of the elastic properties of BFO is highly desired for BFO integration in nanoelectronic devices. Moreover, our findings highlight also that BFO may be a good candidate for light-controlled coherent acoustic phonons sources. [ABSTRACT FROM AUTHOR]

We demonstrate by experiment and theoretical analysis that the presence of built-in electric fields near the (111) and [formula] surfaces of p-doped GaAs causes efficient generation of acoustic waves due to the laser-induced inverse piezoelectric effect. At the same time, the generation efficiency from the electron-hole-phonon deformation potential is shown to be reduced. The polarity of the acoustic pulse is inverted when changing the laser irradiated surface from (111) to [formula]. The results have ramifications for optically controlled piezoelectric ultrasound transducers. [ABSTRACT FROM AUTHOR]

We achieve depth-profiling of the elasticity of a thin transparent film of a nanoporous low-k material using picosecond acoustic interferometry. The variation in the material properties with depth is extracted from time-resolved femtosecond optical reflectivity measurements. More than 40% of the variation in the longitudinal elastic modulus between the front and the back surfaces of an 800 nm thick nanoporous layer is mapped with a 40 nm spatial resolution. We attribute this variation to the spatially inhomogeneous UV curing of the film during fabrication. [ABSTRACT FROM AUTHOR]

The theoretical backgrounds for the depth-profiling of the optically transparent materials by picosecond ultrasonic interferometry are developed. The mathematical description of the light reflection from inhomogeneous transparent films or coatings is proposed. The inhomogeneity can be caused both by the film synthesis (intrinsic stationary inhomogeneity) and by the short acoustic transients launched in the film (time-dependent inhomogeneity). The theory indicates that the measurements of the complex optical reflectivity time evolution, caused by acoustic strain pulse propagation in such films, offer various possibilities to extract the depth profiles of intrinsic inhomogeneous distributions of mechanical/acoustical, optical, and acousto-optical parameters of the films. In particular it is proposed how the measurements of the transient complex optical reflectivity by the femtosecond optical interferometers, operating with light of different polarizations and probing the tested samples at different angles of light incidence, can be used. The spatial resolution of the method is limited by the acoustic spatial scale which, for picosecond acoustic pulses, is much shorter than optical wavelength. [ABSTRACT FROM AUTHOR]

Cystic fibrosis (CF) is a genetic disorder that alters chloride transport in mucous membranes. Recent studies have demonstrated that treatment with modulators of the chloride channel reduces inflammatory markers, restoring, among others, the imbalance of lipids. In this study, we analyzed the serum samples of treated and non-treated patients with modulators with Raman spectroscopy. Nineteen (eight treated an eleven non-treated) patients were considered. The main difference between the two groups appeared in the 3020–2800 cm−1 range. A Voigt deconvolution fit was performed, and nine sub-bands were identified. To distinguish between treated and non-treated patients, the area ratio between the CH3 and CH2 vibration modes was calculated for each patient. The results were validated using statistical analyses. In particular, receiver operating characteristic (ROC) curves and Youden index (Y) were calculated (Area Under Curve (AUC): 0.977; Y: 3.30). An ROC curve represents the performance of the classification, illustrating the diagnostic ability of Raman spectroscopy. It was demonstrated that Raman spectroscopy is able to highlight peculiar differences between elexacaftor/tezacaftor/ivacaftor (ETI)-treated and non-treated patients, in relation with lipids biomarkers. [ABSTRACT FROM AUTHOR]

Background The poor health status of underserved populations is compounded by low vaccination uptake, leading to a greater risk of epidemics. On October 2017, a measles outbreak started in the southwest of France among under-vaccinated social groups, including Travellers. We aimed to describe the health status, healthcare use and child measles–mumps–rubella (MMR) vaccination coverage in Travellers according to their environmental and living conditions. Methods A cross-sectional study with a three-stage random sample design was conducted between October 2019 and March 2022 in the Nouvelle-Aquitaine region in France. Trained social workers administered face-to-face questionnaires to collect data on adults and children. Anthropometric measurements, vaccination records and data using an environmental exposure questionnaire were also collected. Results The participation rate was high (73.6%), with 1030 adults and 337 children included. Concerning the adults, 36.6% had obesity, 14.4% reported diabetes, 24.7% hypertension and 14.4% major depression. The prevalence of major depression was significantly higher in adults living in precarious and unauthorized housing than in those with adequate housing (19.8 vs. 14.7%, P  = 0.03). With regard to children, 45.3% had full (i.e. 2-dose) MMR vaccination coverage at 24 months and 17.9% had obesity. Finally, 74.5% of the households experienced housing insecurity, and 22.2% did not have a supply of drinking water. Conclusion Traveller children and adults faced deleterious environmental and living conditions potentially affecting their health, healthcare use and vaccination coverage. These results demonstrate the need for urgent interventions for underserved populations which take into account their specific needs. [ABSTRACT FROM AUTHOR]

Ultrashort light pulses induce rapid deformations of crystalline lattices. In ferroelectrics, lattice deformations couple directly to the polarization, which opens the perspective to modulate the electric polarization on an ultrafast time scale. Here, we report on the temporal and spatial tracking of strain and polar modulation in a single-domain BiFeO3 thin film by ultrashort light pulses. To map the light-induced deformation of the BiFeO3 unit cell, we perform time-resolved optical reflectivity and time-resolved x-ray diffraction. We show that an optical femtosecond laser pulse generates not only longitudinal but also shear strains. The longitudinal strain peaks at a large amplitude of 0.6%. The access of both the longitudinal and shear strains enables to quantitatively reconstruct the ultrafast deformation of the unit cell and to infer the corresponding reorientation of the ferroelectric polarization direction in space and time. Our findings open new perspectives for ultrafast manipulation of strain-coupled ferroic orders. [ABSTRACT FROM AUTHOR]

The article presents the results of a study of the effect of thermal acid treatment of kaolinite on increasing its adsorption activity. Previous publications have presented the results of a study of the synthesis conditions and properties of the TiO2/kaolinite material—a filler of building materials with the function of passive degradation of household organic pollutants; the studies showed a significant increase in the adsorption–structural characteristics of the composite during synthesis compared to kaolinite and titanium dioxide as separate materials. The current article is devoted to study of changes in the sorption activity of potential carriers of titanium dioxide—kaolinite and montmorillonite—as a result of thermal acid treatment, which simulates the synthesis of a composite. A significant increase in the adsorption activity of kaolinite is obtained and the inefficiency of this treatment method for montmorillonite is shown. [ABSTRACT FROM AUTHOR]

The present paper aims to evaluate the performance of photocatalytic lightweight indoor hydraulic lime-based finishing mortars, with Portland cement-based finishing mortar as a reference. Two different types of aggregates, expanded glass and expanded silicate, are utilized to achieve the lightweight character and their contributions are investigated. The pore structure of the developed mortars is determined by mercury intrusion porosimetry (MIP) and BET methods. The mechanical strength, drying shrinkage, thermal physical properties and air pollutant removal ability of the mortars are investigated and the effects of pore structure on these properties are evaluated. Due to the higher porosity, lime-based finishing mortars possess a higher capillary water absorption and higher drying shrinkage, which can be explained by the Kelvin-Laplace mechanism. The lime-based mortar shows very good thermal properties, with a thermal conductivity of 0.15 W/(m·K). The lime-based mortar shows a better ability of removing air pollutants, up to 46% under indoor air conditions laboratory test, compared to the cement-based mortar, which is attributed to the lower content of gel pores present in the lime-based mortar. Expanded glass shows positive influences concerning thermal properties and air pollutant removal ability compared to expanded silicate. [ABSTRACT FROM AUTHOR]

Spin/charge interconversion mechanisms provide an essential handle to generate and detect spin currents. Their applications at different timescales are critical in spintronics since they cover a technologically relevant broadband spectrum. While the inverse spin Hall effect is known to be robust from quasi-static to sub-picosecond timescales, the conversion efficiency evolution of the inverse Edelstein effect has not been addressed yet. In this work, we report that while the quasi-static response of the inverse Edelstein effect can be comparable to that of the most efficient inverse spin Hall systems, a drastic drop of efficiency is observed in the terahertz (THz) regime. This behavior at the sub-picosecond timescale is qualitatively understood from the dependence of the inverse Edelstein effect on the energy distribution of spin-carrier entities, which is different between thermalized carriers in the quasi-static regime and hot carriers generated by light pulses. This finding is supported by the pump-laser wavelength dependence in the THz regime for the inverse Edelstein effect, which offers a promising route for tunability of spintronic devices. [ABSTRACT FROM AUTHOR]

Chikungunya is an arboviral disease causing arthralgia which may develop into a debilitating chronic arthritis. In Mayotte, a French overseas department in the Indian Ocean, a chikungunya outbreak was reported in 2006, affecting a third of the population. We aimed at assessing the chikungunya seroprevalence in this population, after over a decade from that epidemic. A multi-stage cross sectional household-based study exploring socio-demographic factors, and knowledge and attitude towards mosquito-borne disease prevention was carried out in 2019. Blood samples from participants aged 15–69 years were taken for chikungunya IgG serological testing. We analyzed associations between chikungunya serological status and selected factors using Poisson regression models, and estimated weighted and adjusted prevalence ratios (w/a PR). The weighted seroprevalence of chikungunya was 34.75% (n = 2853). Seropositivity for IgG anti-chikungunya virus was found associated with living in Mamoudzou (w/a PR = 1.49, 95%CI: 1.21–1.83) and North (w/a PR = 1.41, 95%CI: 1.08–1.84) sectors, being born in the Comoros islands (w/a PR = 1.30, 95%CI: 1.03–1.61), being a student or unpaid trainee (w/a PR = 1.35, 95%CI: 1.01–1.81), living in precarious housing (w/a PR = 1.30, 95%CI: 1.02–1.67), accessing water streams for bathing (w/a PR = 1.72, 95%CI: 1.1–2.7) and knowing that malaria is a mosquito-borne disease (w/a PR = 1.42, 95%CI: 1.21–1.83). Seropositivity was found inversely associated with high education level (w/a PR = 0.50, 95%CI: 0.29–0.86) and living in households with access to running water and toilets (w/a PR = 0.64, 95%CI: 0.51–0.80) (n = 1438). Our results indicate a long-lasting immunity from chikungunya exposure. However, the current population seroprevalence is not enough to protect from future outbreaks. Individuals naïve to chikungunya and living in precarious socio-economic conditions are likely to be at high risk of infection in future outbreaks. To prevent and prepare for future chikungunya epidemics, it is essential to address socio-economic inequalities as a priority, and to strengthen chikungunya surveillance in Mayotte. [ABSTRACT FROM AUTHOR]

Marine and terrestrial natural surfaces exhibit statistical scale invariance properties that are well modelled by fractional Brownian motion (fBm), two-dimensional random processes. Accordingly, for microwave remote sensing applications it is useful to evaluate the normalized radar cross section (NRCS) of fBm surfaces. This task has been accomplished in the past by using either the Kirchhoff approximation (KA) or the small perturbation method (SPM). However, KA and SPM have rather limited ranges of application in terms of surface roughness and incidence angle: a wider range of application is achieved by the small slope approximation (SSA), more recently developed, but the latter has not been applied yet to fBm surfaces. In this paper, the first-order SSA (SSA-1) is applied to the evaluation of scattering from fBm surfaces obtaining an analytical formulation of their NRCS. It is then shown that the obtained SSA-1 expression reduces to the KA and SPM ones at near-specular and far-from-specular scattering directions, respectively. Finally, the results of the proposed method are compared to experimental data available in the literature. [ABSTRACT FROM AUTHOR]

The urban growth leads cities to adopt sustainable strategies in order to mitigate the relevant hydrological effects. In this study, the use of synthetic aperture radar SAR imagery has allowed us to demonstrate a 70% increase of the built-up area in Sarno River basin between 1995 and 2016. This increase is linked to the statistical temporal increase of the damaging hydrological events occurring during the same period. To restore the pre-development hydrological condition, a scenario analysis was undertaken where SWMM was used to simulate the hydrological effect of green roof retrofitting landscape design. SAR imagery was furthermore used to explore the potential retrofitting surfaces, leading to defining three different conversion scenarios with 5%, 30% and 100% of potential retrofitting surfaces. The study demonstrated that the predevelopment hydrological condition can be never fully restored. Indeed, this scenario is partially equaled only by a 100% green conversion of the existing traditional roofs, with average runoff and peak flow reduction of 41% and 25%, respectively. Such conditions are clearly not feasible, provided the obvious retrofitting limitation for existing buildings. The use of additional nature-based techniques, beyond green roofs conversion, should be explored in the perspective of a balance for urban growth. [ABSTRACT FROM AUTHOR]

Mapping urban areas from space is a complex task involving the definition of what should be considered as part of an urban agglomerate beyond the built-up features, thus modelling the transition of a city into the surrounding landscape. In this paper, a new technique to map urban areas using multitemporal synthetic aperture radar data is presented. The proposed methodology exploits innovative RGB composites in combination with self-organizing map (SOM) clustering and object-based image analysis. In particular, the clustered product is used to extract a coarse urban area map, which is then refined using object-based processing. In this phase, Delaunay triangulation and the spatial relationship between the identified urban regions are used to model the urban–rural gradient between a city and the surrounding landscape. The technique has been tested in different scenarios representative of structurally different cities in Italy and Germany. The quality of the obtained products is assessed by comparison with the Urban Atlas of the European Environmental Agency, showing good agreement with the adopted reference data despite their different taxonomies. [ABSTRACT FROM AUTHOR]

The knowledge of the hydro-morphological evolution of lowland rivers is essential to develop integrated river management plans. Satellite data can provide continuous and efficient means to monitor fluvial geomorphological changes at various spatiotemporal scales. In this study, an automatic classification method was exploited to analyze the evolution of a 40km reach of the Italian Po River from 1986 to 2020. Public domain multispectral satellite data acquired by Landsat 4-5-TM, Landsat-8-OLI and Sentinel-2-MSI were processed to extract the wet-channel and its variations over time. Very high-resolution GeoEye-01 and WorldView-02 images were employed for validating the classification method. The overall accuracy, obtained by multitemporal controls with very high-resolution images, was always greater than 0.90 for all the missions, showing that the classification accuracy remains consistent through time. Combining satellite data with hydrological measurements permitted to monitor the river at the reach scale and investigate the effects of river restoration works. [ABSTRACT FROM AUTHOR]

We describe the neutron diffraction patterns of a series of alkaline borate glasses at different metal oxide content. Strong differences are observed in the intermediate range order as a function of the specific alkaline ion and of its concentration. On these results, we propose that the first sharp diffraction peak arises from correlations of atoms of voids and show that the compositional variation of this peak intensity in alkaline borate glasses is due to changes in the distribution of void sizes within the three-dimensional network. We argue that our interpretation in terms of interstitial (empty and/or filled) voids, having different sizes, provides a general explanation for all anomalous behaviours revealed for the first sharp diffraction peak. [ABSTRACT FROM PUBLISHER]

The SARS-CoV-2 Omicron variant has rapidly replaced the Delta variant of concern. This new variant harbors worrisome mutations on the spike protein, which are able to escape the immunity elicited by vaccination and/or natural infection. To evaluate the impact and susceptibility of different serum samples to the Omicron variant BA.1, samples from COVID-19 patients and vaccinated individuals were tested for their ability to bind and neutralize the original SARS-CoV-2 virus and the Omicron variant BA.1. COVID-19 patients show the most drastic reduction in Omicron-specific antibody response in comparison with the response to the wild-type virus. Antibodies elicited by a triple homologous/heterologous vaccination regimen or following natural SARS-CoV-2 infection combined with a two-dose vaccine course, result in highest neutralization capacity against the Omicron variant BA.1. Overall, these findings confirm that vaccination of COVID-19 survivors and booster dose to vaccinees with mRNA vaccines is the correct strategy to enhance the antibody cross-protection against Omicron variant BA.1. Antibodies elicited by a triple homologous or heterologous vaccination regimen or following natural SARS-CoV-2 infection combined with a two-dose vaccine course, result in highest neutralization capacity against the Omicron variant BA.1. [ABSTRACT FROM AUTHOR]

Background: The recently emerged SARS-CoV-2 Omicron variant exhibits several mutations on the spike protein, enabling it to escape the immunity elicited by natural infection or vaccines. Avidity is the strength of binding between an antibody and its specific epitope. The SARS-CoV-2 spike protein binds to its cellular receptor with high affinity and is the primary target of neutralizing antibodies. Therefore, protective antibodies should show high avidity. This study aimed at investigating the avidity of receptor-binding domain (RBD) binding antibodies and their neutralizing activity against the Omicron variant in SARS-CoV-2 infected patients and vaccinees.Methods: Samples were collected from 42 SARS-CoV-2 infected patients during the first pandemic wave, 50 subjects who received 2 doses of mRNA vaccine before the Omicron wave, 44 subjects who received 3 doses of mRNA vaccine, and 35 subjects who received heterologous vaccination (2 doses of adenovirus-based vaccine plus mRNA vaccine) during the Omicron wave. Samples were tested for the avidity of RBD-binding IgG and neutralizing antibodies against the wild-type SARS-CoV-2 virus and the Omicron variant.Results: In patients, RBD-binding IgG titers against the wild-type virus increased with time, but remained low. High neutralizing titers against the wild-type virus were not matched by high avidity or neutralizing activity against the Omicron variant. Vaccinees showed higher avidity than patients. Two vaccine doses elicited the production of neutralizing antibodies, but low avidity for the wild-type virus; antibody levels against the Omicron variant were even lower. Conversely, 3 doses of vaccine elicited high avidity and high neutralizing antibodies against both the wild-type virus and the Omicron variant.Conclusions: Repeated vaccination increases antibody avidity against the spike protein of the Omicron variant, suggesting that antibodies with high avidity and high neutralizing potential increase cross-protection against variants that carry several mutations on the RBD. [ABSTRACT FROM AUTHOR]

Background: Located in southwestern Indian Ocean, Mayotte is a French territory, with a very specific demographic, social and health context. To date, epidemiological data on infections by hepatitis B (HBV), C (HCV), and delta (HDV) viruses in Mayotte have been sparse. We aimed to estimate, in the 15-69-year-old general population living in Mayotte, the prevalence of infections by hepatitis B (HBV), C (HCV), and delta (HDV) viruses and the distribution of HBV status: current infection with positive HBs antigen (Ag); resolved infection with positive HBc antibodies and negative HBsAg; immunisation by vaccination with only positive HBs antibodies; and no infection/no immunisation with negative markers. We also described the characteristics of infected people and assessed the determinants of lifetime HBV infection.Methods: The Unono Wa Maore survey, implemented in a random sample of the general population in 2018-2019, consisted of an at-home collection of epidemiological data and venous blood samples. Detection of hepatitis B, C, and delta serological and molecular markers was performed.Results: Among 5207 eligible people, 4643 responded to the questionnaire (89.2%), with 2917 being tested for HBV and HCV (62.8%). Estimated HBV status was as follows: current infection 3.0% (95% confidence interval [CI]: 2.3-3.9%) (n = 76); resolved infection 27.8% (95% CI: 25.8-29.9); immunisation by vaccination 27.7% (95% CI: 25.9-29.7); and no infection/no immunisation 41.5% (95% CI: 39.3-43.7). One participant was positive for HDV antibodies (Ab) (0.65%) with a negative HDV-RNA viral load. The risk of lifetime HBV infection was higher in men (adjusted prevalence ratio (aPR): 1.55, 95% CI: 1.29-1.89); in people aged 30-49 years (aPR: 3.83, 95% CI: 1.49-9.81) or 50-69 years (aPR: 4.52, 95% CI: 1.77-11.53) compared to those under 20; in individuals who reported no condom use during their first sexual intercourse (aPR: 1.46, 95% CI: 1.01-2.14); and in those living in Dembeni-Mamoudzou (aPR: 1.40, 95% CI: 1.09-1.80) compared to the West-Centre of Mayotte. Finally, six individuals were positive for HCV antibodies (0.21%), including three positive for HCV RNA.Conclusions: Mayotte is an area of intermediate endemicity for HBV and low endemicity for HCV and HDV. With a prevalence of HBsAg 10 times higher than in mainland France, a high proportion of people susceptible to HBV infection, and a demographic, health, and social context that may favour its transmission, hepatitis B is a major public health concern in Mayotte. [ABSTRACT FROM AUTHOR]

No-fines concrete with a compressive strength in the range 7-30MPa at 28days of curing were optimized by changing the water/cement ratio from 0.41 to 0.34 and the aggregate/cement ratio from 8 to 4. Some mixtures were also repeated with the addition of a hydrophobic admixture and prepared by fully replacing the ordinary aggregate with recycled aggregate to evaluate durability effects. High susceptibility to carbonation was observed for all the no-fines mixes studied. The use of recycled aggregate increases capillary water absorption (about 50%); however, the related decrease in durability could be easily counteracted with the use of a hydrophobic admixture. [ABSTRACT FROM AUTHOR]

Abstract: The landscape around the Graeco-Roman town of Neapolis was reconstructed through morphostratigraphic methods and pollen analysis of the sediments filling the bay hosting the ancient harbor. This was discovered in 2004 thanks to excavations for two new lines of the Naples metro network; the harbor's sedimentary record spans the period between the late 4th century BC and the 6th century AD. The main changes occurring in the marine and terrestrial landscape surrounding the ancient town are highlighted through the reconstruction of a detailed geological cross section and four 3D palaeogeographic models. Pollen analysis suggested the presence of mixed oak woods on the slopes surrounding the town and of vegetable gardens around the harbor area. The tree crops mainly consisted of walnut, and to a lesser extent chestnut and grapevines. The horticultural varieties were dominated by Brassicaceae, most likely representing cabbage cultivation which was rather common in Roman times. Comparison with reference pollen material reinforces this hypothesis. During the 3rd century AD a drastic decrease in horticultural activity, in concurrence with an increase in wild vegetation and tree crops, suggest reduced maintenance due to a phase of abandonment. Historical data imply for the same period a phase of economic and social decline which involved the whole Empire. From the end of the 3rd century AD, the growth of a spit bar at the port entrance gave rise to the establishment of a lagoon and then to the final closure of the bay. [Copyright &y& Elsevier]