VUV-Vis optical characterization of Tetraphenyl-butadiene films on glass and specular reflector substrates from room to liquid Argon temperature

The use of efficient wavelength-shifters from the vacuum-ultraviolet to the photosensor's range of sensitivity is a key feature in detectors for Dark Matter search and neutrino physics based on liquid argon scintillation detection. Thin film of Tetraphenyl-butadiene (TPB) deposited onto the surface delimiting the active volume of the detector and/or onto the photosensor optical window is the most common solution in current and planned experiments. Detector design and response can be evaluated and correctly simulated only when the properties of the optical system in use (TPB film + substrate) are fully understood. Characterization of the optical system requires specific, sometimes sophisticated optical methodologies. In this paper the main features of TPB coatings on different, commonly used substrates is reported, as a result of two independent campaigns of measurements at the specialized optical metrology labs of ENEA and University of Tor Vergata. Measured features include TPB emission spectra with lineshape and relative intensity variation recorded as a function of the film thickness and for the first time down to LAr temperature, as well as optical reflectance and transmittance spectra of the TPB coated substrates in the wavelength range of the TPB emission

Strategy and criteria to optically design a solar concentration plant

AbstractThe objective of this work is to individuate the best strategy to determine the layout of a thermodynamic plant based on the concentration of solar flux by means of a large number of mirrors. Many software tools exist, both dedicated software and more general optical software. This analysis shows the advantages derived from the use of a general non-sequential optical software, proposing criteria and procedures in order to establish dedicated optical merit figures, which are suggested and evaluated from the point of view of their effectiveness to achieve a favorable layout design. Particular attention is devoted to merit figures that estimate the optical efficiency, a key quantity for all the CSP plants that can be defined in different ways. The description includes examples of application, discussion of results and various proposed alternatives for the merit figure

Bioregulators can improve biomass production, photosynthetic efficiency, and ornamental quality of gazania rigens L

Gazania rigens L. is a perennial herbaceous plant that belongs to the Asteraceae family, widely used as bedding or ornamental potted plants. The environmental and economic sustainability of ornamental production can be enhanced using environmentally friendly bioregulators. A pot experiment was conducted to evaluate the influence of key bioregulators gibberellic acid ((GA3) at 50, 100 or 150 mg L 121), humic acid ((HA) at 100, 300 or 600 mg L 121), and ascorbic acid ((AA) at 50, 100 or 200 mg L 121)), on the growth, leaf gas exchange, and ornamental quality of G. rigens. The results indicated that plants treated with foliar applications of GA3, HA, or AA exhibited higher plant fresh and dry biomass, plant height, leaf area, and leaf area ratio, root-shoot ratio, root-shoot mass fractions, and number of flowers, as well as the flowers display time. All bioregulator treatments enhanced the vegetative and floral characteristics of Gazania plants. The GA3 was the most efficient at the concentration of 100 mg L 121. The highest efficacy of HA and AA treatments was observed at the higher concentrations, 600 and 200 mg L 121, respectively. These results were associated with higher photosynthetic rate (A), transpiration rate (E) as well as stomatal conductance (gs), and water use efficiency (WUE). In conclusion, the results suggest that foliar-applied bioregulators to Gazania are promising and represent sustainable strategies to enhance growth, flowering, and flower display time of Gazania plants

Psychological impact and health-related quality-of-life outcomes of Mayer-Rokitansky-Küster-Hauser syndrome : A systematic review and narrative synthesis

Mayer-Rokitansky-K\ufcster-Hauser syndrome causes absence or underdevelopment of uterus and vagina, but women's subjective experience remains understudied. This systematic review was conducted to examine the psychological and health-related quality-of-life outcomes of Mayer-Rokitansky-K\ufcster-Hauser syndrome. In total, 22 articles identified through electronic search matched the inclusion criteria and were included in our review. Mayer-Rokitansky-K\ufcster-Hauser syndrome may be associated with psychological symptoms and impaired quality of life, but especially with poor sexual esteem and genital image. Women may experience difficulties managing intimacy and disclosing to partners. Mothers may be perceived as overinvolved, with consequent negative emotions in women with the disease

CFD MODELING OF SOLAR COLLECTOR WITH NANO-FLUID DIRECT ABSORPTION FOR CIVIL APPLICATION

Direct solar absorption has been considered often in the past as a possible configuration of solar thermal collectors for residential and small commercial applications. Of course, a direct absorption could improve the performance of solar collectors by skipping one step of the heat transfer mechanism of standard devices and by modifying the temperature distribution inside the collector. In fact, classical solar thermal collectors have a metal sheet as absorber, designed such that water has the minimum temperature in each transversal section, in order to collect as much as possible the solar thermal energy. On the other hand, in a direct configuration, the hottest part of the system is the operating fluid and this allows to have a more efficient conversion. Nanofluids, i.e. fluids with a suspension of nano-particles, as carbon nano-horns, could be a good and innovative family of absorbing fluids, for their higher absorption coefficient with respect to the base fluid and stability under moderate temperature gradients. Moreover, carbon nanohorns offer the significant advantage to be non-toxic unlike other carbon nanoparticles (e.g. carbon nanotubes). In this work, an original 3D model of the absorption phenomena in nano-fluids flowing in a cylindrical tube is coupled with a CFD analysis of the flow and temperature field. Recent measurements of the optical properties of nano-fluids with different concentrations have been used for the radiation heat transfer modeling and included in the fluid dynamic modeling as well. Heat losses due to conduction, convection and radiation at the boundaries are included in the model. The results are compared with the typical performance of flat solar collectors present on the marke

Extrinsically conductive nanomaterials for cardiac tissue engineering applications

Myocardial infarction (MI) is the consequence of coronary artery thrombosis resulting in ischemia and necrosis of the myocardium. As a result, billions of contractile cardiomyocytes are lost with poor innate regeneration capability. This degenerated tissue is replaced by collagen-rich fibrotic scar tissue as the usual body response to quickly repair the injury. The non-conductive nature of this tissue results in arrhythmias and asynchronous beating leading to total heart failure in the long run due to ventricular remodelling. Traditional pharmacological and assistive device approaches have failed to meet the utmost need for tissue regeneration to repair MI injuries. Engineered heart tissues (EHTs) seem promising alternatives, but their non-conductive nature could not resolve problems such as arrhythmias and asynchronous beating for long term in-vivo applications. The ability of nanotechnology to mimic the nano-bioarchitecture of the extracellular matrix and the potential of cardiac tissue engineering to engineer heart-like tissues makes it a unique combination to develop conductive constructs. Biomaterials blended with conductive nanomaterials could yield conductive constructs (referred to as extrinsically conductive). These cell-laden conductive constructs can alleviate cardiac functions when implanted in-vivo. A succinct review of the most promising applications of nanomaterials in cardiac tissue engineering to repair MI injuries is presented with a focus on extrinsically conductive nanomaterials

Fluorescent silver nanoclusters embedded in hydrogel matrix and its potential use in environmental monitoring

The optical absorption and fluorescence of silver nanoclusters (AgNCs) are widely exploited in many different application fields such as sensors, bio-imaging, drug delivery, etc. In the sensor field, optical devices are highly versatile thanks to their ease of fabrication and low costs and, therefore, are optimal candidates to replace expensive apparatuses commonly used. In this study, we synthesized AgNCs in aqueous phase by photochemical synthesis using poly methacrylic acid (PMAA) as a stabilizer. Colloidal water solutions of these NCs showed a very good sensitivity to Pb(II) ions, and in order to fabricate a solid-state sensor, we introduced them in a hydrogel material formed by poly(ethylene glycol) diacrylate with a molecular weight of 700 g/mol (PEGDA(700)). The systems were characterized using absorption and fluorescence spectroscopy and transmission electron microscopy (TEM). Finally, the sensitivity to Pb(II) ions has been tested with the aim to use these systems as solid-state optical sensors for water quality

Fluorescent Silver Nanoclusters Embedded in Hydrogel Matrix and Its Potential Use in Environmental Monitoring

The optical absorption and fluorescence of silver nanoclusters (AgNCs) are widely exploited in many different application fields such as sensors, bio-imaging, drug delivery, etc. In the sensor field, optical devices are highly versatile thanks to their ease of fabrication and low costs and, therefore, are optimal candidates to replace expensive apparatuses commonly used. In this study, we synthesized AgNCs in aqueous phase by photochemical synthesis using poly methacrylic acid (PMAA) as a stabilizer. Colloidal water solutions of these NCs showed a very good sensitivity to Pb(II) ions, and in order to fabricate a solid-state sensor, we introduced them in a hydrogel material formed by poly(ethylene glycol) diacrylate with a molecular weight of 700 g/mol (PEGDA700). The systems were characterized using absorption and fluorescence spectroscopy and transmission electron microscopy (TEM). Finally, the sensitivity to Pb(II) ions has been tested with the aim to use these systems as solid-state optical sensors for water quality

The new hyperspectral satellite prisma: Imagery for forest types discrimination

Different forest types based on different tree species composition may have similar spectral signatures if observed with traditional multispectral satellite sensors. Hyperspectral imagery, with a more continuous representation of their spectral behavior may instead be used for their classification. The new hyperspectral Precursore IperSpettrale della Missione Applicativa (PRISMA) sensor, developed by the Italian Space Agency, is able to capture images in a continuum of 240 spectral bands ranging between 400 and 2500 nm, with a spectral resolution smaller than 12 nm. The new sensor can be employed for a large number of remote sensing applications, including forest types discrimination. In this study, we compared the capabilities of the new PRISMA sensor against the well-known Sentinel-2 Multi-Spectral Instrument (MSI) in recognition of different forest types through a pairwise separability analysis carried out in two study areas in Italy, using two different nomenclature systems and four separability metrics. The PRISMA hyperspectral sensor, compared to Sentinel-2 MSI, allowed for a better discrimination in all forest types, increasing the performance when the complexity of the nomenclature system also increased. PRISMA achieved an average improvement of 40% for the discrimination between two forest categories (coniferous vs. broadleaves) and of 102% in the discrimination between five forest types based on main tree species groups