353 research outputs found
Porous silicon coatings for photovoltaic devices
No full textPorous silicon was formed on multicrystalline Si substrates by stain etching in aqueous HF/HNO3 solutions. In this work optical and electrical properties of the resulting films are discussed as a function of process parameters. Porous-Si films have been shown to be able to reduce surface reflectance to 3% in 350-700 nm wavelength range and their application in anti-reflection coating of photovoltaic solar cells has been demonstrated, obtaining (10×10) cm2 multicrystalline Si solar cells with efficiency approaching 12% under standard AM 1.5 simulated sunlight
Grafici di funzione nella Scuola Primaria
No full textIl seguente articolo mostra i risultati di una sperimentazione didattica condotta in una quarta classe di Scuola Primaria relativa alla lettura e comprensione di grafici di funzioni. Le lezioni si sono svolte in assetto laboratoriale, facendo uso di un sensore di movimento. La nostra ricerca corrobora i precedenti lavori sugli strumenti MBL, secondo cui l’uso del sensore di movimento permette agli studenti di migliorare le competenze riguardanti la lettura, comprensione e interpretazione di grafici cinematici; inoltre mostra che l’utilizzo del sensore di movimento migliora tali competenze rispetto ad altri tipi di grafici, e in particolare, grafici di funzioni rappresentati fenomeni statistici. Questi risultati sono emersi dall’analisi statistica implicativa e qualitativa dei pre- e post-test e dall’analisi qualitativa delle lezioni in classe
macroporous thin-layers on p-type silicon: electrochemical preparation and applications
No full textpavi
Cost Analysis of Scleral Buckle and Pars Plana Vitrectomy for Retinal Detachment Surgery
No full textÁlvaro J Rallo-López,1 Rafael Martínez-Costa Pérez2 1Department of Ophthalmology, Clínica Baviera, Valencia, Spain; 2Department of Ophthalmology – Retina and Vitreous, Hospital Universitario y Politécnico La Fe, Valencia, SpainCorrespondence: Álvaro J Rallo-López, Email [email protected] and Objective: To compare the cost and utility of scleral buckle (SB) and pars plana vitrectomy (PPV) techniques for repairing moderately complex rhegmatogenous retinal detachment (RRD).Patients, Materials, and Methods: A cost-utility analysis was conducted using data from the Primary Retinal Detachment Outcomes Study (PRO) and a study conducted by the author. Total costs, patient utility over a lifetime, and cost per quality-adjusted life year (QALY) were calculated for each surgical procedure.Results: The cost of scleral buckle surgery was € 287.93, with an estimated lifetime QALY of 7.49. Costs per QALY were € 38.44. According to the PRO study and Belin et al, total costs were $5975, with a lifetime QALY of 5.4 and costs per QALY of $1106. The cost of pars plana vitrectomy (PPV) was € 1468.26, with an estimated lifetime QALY of 6.84 and costs per QALY of € 214.65. Based on the PRO study and Belin et al, total costs were $8125, with a lifetime QALY of 4.7 and costs per QALY of $2196.Conclusion: Repairing moderately complex RRD presents a highly cost-effective profile for both SB and PPV techniques, well below recommended QALY thresholds. SB demonstrated a slightly more favorable profile compared to PPV.Keywords: retinal detachment, pars plana vitrectomy, scleral buckle, cost-utility analysis, QAL
Medically assisted procreation in times of COVID-19: what impact on health care system organization and the reproductive rights of couples?
No full textThe emergency caused by the spread of COVID-19 has overwhelmed health care facilities and required the reorganization of health systems in many nations worldwide. Objective: The article aims to illustrate the measures aimed at containing the spread of SARS-CoV-2 and their impact on those seeking medically-assisted procreation procedures. Materials and Methods: By drawing upon international sources and documents from ethics committees and scientific societies about the COVID-19 pandemic and MAP, the article aims to expound upon and assess the measures issued by the Italian government in order to counter the spread of COVID-19. Results: The coronavirus disease 2019 (COVID-19) has had a major impact on infertile couples. Since the pandemic broke out, Italy, like most European countries, has interrupted most ordinary activities of the centers operating in the field of assisted fertilization. Discussion: Such measures are based on the principles of responsibility and solidarity, essential to stave off the saturation of health systems, curb contagion, but also to lay out a set of rules to starting a pregnancy while preserving the health of couples, operators and newborns. The authors also expound upon the rights claimed by couples seeking access to MAP (i.e. the right to become a parent, the couple’s right to health). Conclusions: We believe that access to assisted fertilization techniques by sterile and infertile couples should be part of the right to health rather than of the supposed right to become parents or the increase in the birth rate, also evoked as the COVID-19 pandemic unfolded
Agro-hydrological models to schedule irrigation of Mediterranean tree crops
No full textIn this paper a comparison between two agro-hydrological models, used to schedule irrigation of typical Mediterranean tree crops, is assessed. In particular the comparison between the model proposed by FAO, using a black box processes schematization, and the SWAP model based on the numerical analysis of Richards’ equation is initially presented for two irrigation seasons, 2005 and 2006, and two Mediterranean tree crops, i.e. grapevine (Vitis vinifera, L.) and olive oil (Olea europea, L.). The comparison mainly focuses on hydrological balance components and on soil
water contents.
After investigating and setting the scheduling parameters ordinarily practiced by the framers in the area (i.e ordinary management), the performance of the two models aimed to evaluate seasonal water requirement and irrigation time, is assessed.
In the validation phase both the models satisfactorily simulated the soil water content, allowing to obtain quite comparable values of evapotraspiration fluxes. On the other hand, when the models are used for scheduling irrigation, the FAO 56 model usually overestimates the irrigation amount, as a result of an overestimation of the transpiration fluxes. On the contrary the SWAP model simulates values of crops water requirements and a number of irrigation corresponding to those evaluated in the ordinary scheduling at the investigated area. Finally, in order to improve the FAO 56 model performance, a modification of the stress function is presented and discussed
Comment on the article by Zaami et al "Increasing abuse of anabolic steroids and chemsex drugs as performance and image-enhancing agents". Eur Rev Med Pharmacol Sci 2021; 25: 455-458
No full textDispositivo per la determinazione di una grandezza cinematica di una bicicletta e della cadenza di pedalata esercitata sui pedali di detta bicicletta
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