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Double-nanotextured black diamond films with different geometries were fabricated by double-step femtosecond laser treatments at different split ratios of accumulated laser fluence. A "2D-like" pseudo-periodic nanostructure was obtained for the first time when the split ratio was slightly unbalanced in favour of the first step of the treatment, as inferred by scanning electron microscopy. Raman analysis showed that a residual biaxial stress, composed by a superposition of a tensile and a compressive component, is always present after the laser writing process, and that the two components tend to balance each other in the 2D pseudo-periodic case. Spectrophotometric measurements in the 200 e2000 nm wavelength range returned outstanding solar absorptance values for all the fabricated films (reaching the unprecedented value of 99.1% in the "2D-like" structure), launching double-nanotextured black diamond as a possible alternative to black silicon as absorbing layer for high-efficiency solar cells.

Magnesium hydride has been proposed as innovative anode material for Li ion cells due to its large theoretical capacity and high-energy efficiency compared to other conversion Materials. In this work, we report a combined experimental-theoretical study about the origin of voltage hysteresis in, the Conversion reaction of MgH2 in lithium cells. Experimentally, the extent of the thermodynamic voltage hysteresis in the first galvanostatic discharge charge cycle has been determined by the GITT technique and decoupled from the kinetic overpotentials. Theoretically, the origin of the thermodynamic voltage hysteresis has been evaluated and studied by means density functional theory calculations within the supercell approach. Different elementary reactions have been modeled upon reduction and oxidation on the surfaces of the active phases (i.e., MgH2, LiH, and Mg), and the associated theoretical voltages have been predicted. Experimental and theoretical results have been compared and discussed to draw a,comprehensive description of the elementary surface reactions of the MgH2 conversion in lithium cells.

The interaction of phosphatidylcholine liposomes used as cell models, with cationic liposomes formulated with 1,2-dimyristoyl-sn-glycero-3-phosphatidylcholine and amphiphiles based on a pyrrolidinium headgroup was investigated by differential scanning calorimetry and fluorescence resonance energy transfer experiments. The results obtained showed that subtle variations in the formulation can influence lipid interactions and were correlated to a previous biological evaluation.

AbstractAimBats are promising candidates for studying morphometric responses to anthropogenic climate or land‐use changes. We assessed whether the cranial size of a common bat (Pipistrellus kuhlii) had changed between 1875 and 2007. We formulated the following hypotheses: (1) if heat loss is an important reaction to climate change, body size will have decreased in response to the increased temperatures, because small bats have a larger surface‐to‐volume ratio and dissipate heat more effectively; (2) if water loss is the main driver, body size will have increased in response to the temperature increase, because larger bats will lose water more slowly through a reduced surface‐to‐volume ratio; (3) the energetic benefits provided by urbanization (food concentration at street lamps, warmer maternity roosts in buildings) will lead to a general body size increase in P. kuhlii; and (4) because street lamps impair moth antipredatory manoeuvres, cranial size may have selectively increased as an adaptive response to handle larger prey (moths) in artificially illuminated sites. Ours is the first study to assess temporal trends in bat body size over more than a century and to relate them to urbanization.LocationMainland Italy.MethodsWe used traditional morphometrics to compare seven variables of skull size in 117 museum specimens (75 female, 42 male).ResultsCranial size increased after 1950, but this change was not paralleled by an increase in body size, measured as forearm length. This selective increase matched a rapid increase in electric public illumination in Italy.Main conclusionsStreet lights are crucial foraging sites for P. kuhlii. The directional change that we found in cranial size might represent microevolutionary adaptive tracking of a sudden shift in food size, making more profitable prey available.

High quality epitaxial crystalline Cu(In,Ga)Se2 (CIGS) films were grown on n-type (1 0 0)--Germanium (Ge) substrates using pulsed electron deposition (PED) technique at a remarkably low substrate temperature of 300 °C, thanks to the high-energy of adatoms arriving to the substrate. The crystalline quality was confirmed by X-ray diffraction techniques and from Transmission Electron Microscopy and the only defects found were twin boundaries along the (1 1 2) direction in these CIGS films; surprisingly neither misfit dislocations nor Kinkerdall voids were observed. A 100 meV optical band located below the band edge was observed by Photoluminescence technique. Current-voltage and capacitance-voltage measurements confirm an intrinsic p-type conductivity of CIGS films, with a free carrier concentration of ?3.5×1016 cm-3. These characteristics of crystalline CIGS films are crucial for a variety of potential applications, such as more efficient absorber layers in single-junction and as an integral component of multi-junction thin-film solar cells.

Among the objectives of the Sustainable Development Goals by United Nations, "Affordable and Clean Energy" aims at ensuring access to affordable, reliable, sustainable and modern energy for all. However, in Europe there is not a precise understanding of the unleashed potential that could be achieved through the exploitation of solar and wind resources. This study presents an application to retrieve spatial explicit estimates of Direct Normal Irradiance (DNI) through the use of data from geo-stationary satellites. The energetic demand of large metropolitan areas in Europe is then retrieved and compared with the potential production of energy for domestic use through solar panels. Results of this comparison are presented based on the assumption that only the 1 % of the built up area could be covered with solar panels, and hence devoted to energy production. Outcomes suggest that even such a little coverage, if spread systematically over urban areas can in most of the cases satisfy urban population domestic needs.

Ethyl glucuronide (EtG) is an ethanol metabolite and EtG is used as a biomarker of alcohol drinking. EtG can be detected in the blood and in several biological matrices including urine, hair and nails. Alcohol consumption during pregnancy is a strong risk factor for fetus health so in the recent years different strategies to reveal alcohol use have been planning including the use of screening questionnaires as the AUDIT-C, T-ACE and TWEAK. The present study aims to investigate in pregnant women the specificity and predictive value of the AUDIT-C, T-ACE and TWEAK plus a food diary in use in Sapienza University Hospital compared with the results of urine EtG measurement. Seventy pregnant women were enrolled and examined. Urine samples were provided by pregnant women immediately after the interviews. EtG determinations were performed by Enzyme Immunoassay with a cut-off established at 100ng/mL. Data show that 34.28% of the enrolled pregnant women overcame the EtG cut off. No direct correlation was found between EtG data and the alcohol screening interviews showing lower levels of alcohol consumption, although T-ACE revealed the same at risk percentage. However, a significant concordance was observed with food diary data and T-ACE only in patients with higher EtG urinary concentration. This study provides clinical evidence that the diagnosis of maternal alcohol consumption during pregnancy only based on indirect methods, such as questionnaires and food diary, may significantly underestimate alcohol use.

A new late-Holocene high-resolution pollen record is presented from Lago Patria with the aim of investigating past vegetation and environmental dynamics in a still under-investigated coastal sector of the Campania region (Italy). Our results show the evolution of a mixed deciduous and evergreen oak-dominated lowland forest, rich in both xeric and mesic woody taxa, under the influence of climate, human impact, geomorphic processes and their interplay. Between 4800 and 2800 cal BP, the pollen record highlights only slight vegetation changes, featured by a modest forest decline around 4200 cal BP, consistent with the deforestation pattern produced by the 4.2 ka arid climate event in southern and central Italy. This event was followed, between 3900 and 3300 cal BP, by a forest recovery with a remarkable development of mesic trees, notably Fagus, influenced by wet climate conditions. While Bronze Age and Iron Age settlements are missing from this coastal area, which suggests a marginal role of human activity in the environmental changes of this period, the continuous presence of anthropogenic pollen indicators in the pollen record stimulates new archeological investigations. Between 2800 and 2200 cal BP, the area experienced successive domination by Greek, Etruscan, Italic and Roman populations, culminating with the foundation and expansion of cities like Cumae, Capua, and Dicearchia/Puteoli, which determined major impact on the natural forest through intense agricultural practices. After a sedimentation hiatus between 2200 and 180 BP, the pollen record documents a few tens of years, during the Bourbon domination, when the vegetational landscape, characterized by cultivations and pasturelands, appears almost completely treeless. Pollen and other palynomorphs of aquatic taxa evidence a change from freshwater to brackish conditions, consistent with the transition from cat's eye freshwater ponds to open lagoon.