169 research outputs found
The ECAPS Experiment for Solar Cell Characterization in the Stratosphere
The ECAPS project (Experimental Characterization of Advanced Photovoltaics in the Stratosphere) aims at the characterization of performance of a number of different solar cells in the stratospheric environment. ECAPS has been selected to fly as a zero-pressure balloon payload in the frame of the HEMERA H2020 project. Flight is scheduled for August 2022 from CNESâ base in Timmins, Canada.
Testing solar cells in the stratosphere is of great interest for the development of High-Altitude Pseudo Satellite (HAPS) platforms, which will be equipped with high efficiency, flexible solar cells capable to operate at 20-30 km altitude for weeks or months, as well as to perform high-quality calibration of spacecraft solar cells in a near-air mass zero environment. The experiment includes a panel with up to 4 solar cells of different kinds (multi-junction GaAs, CIGS, perovskite, etc.), a dedicated I/V curve recording circuit, temperature and irradiance sensors, and an inertial measurement unit to monitor the instantaneous attitude of the gondola.
During the ascent part of the flight, the I/V characteristic curves of the cells will be continuously recorded so to allow for comparison of performance of the different photovoltaic technologies in identical, real stratospheric flight conditions, as well as to detect performance changes with external temperature, irradiance and altitude. Upon recovery of the experiment, post-flight inspection will also yield useful information on the solar cell compatibility with the high altitude environment
Role of α-Tocopherol Acetate on Nasal Respiratory Functions: Mucociliary Clearance and Rhinomanometric Evaluations in Primary Atrophic Rhinitis
Primary atrophic rhinitis is a disease of the nose and of paranasalsinuses characterized by a progressive loss of function of nasal and paranasal mucosa caused by a gradual destruction of ciliary mucosalepithelium with atrophy of serousâmucous glands and loss of bonestructures.The aim of this study was to evaluate the therapeutic effects of topic α-tochopherol acetate (vitamin E) in patients with primary atrophicrhinitis based on subjective and objective data.We analyzed 44 patients with dry nose sensation and endoscopic evidence of atrophic nasal mucosa. We analyzed endoscopic mucosascore, anterior rhinomanometry, and nasal mucociliary clearance before and after 6 months of topic treatment with α-tochopherol acetate. For statistical analysis, we used paired samples t test (95% confidence interval [CI], P <.05) for rhinomanometric and muciliary transit time evaluations and analysis of variance 1-way test (95% CI, P <.05) for endoscopic evaluation. All patients showed an improvement in âdry noseâ sensation and inperception of nasal airflow. Rhinomanometric examination showed increase of nasal airflow at follow-up (P <.05); nasal mucociliaryclearance showed a reduction in mean transit time (P <.05); and endoscopic evaluation showed significative improvement of hydration of nasalmucosa and significative decreasing nasal crusts and mucusaccumulation (P <.05). Medical treatment for primary atrophic rhinitis is not clearly documented in the literature; in this research, it was demonstrated that α-ochopherol acetate could be a possible treatment for atrophic rhinitis
EVOLUTION OF THE (AERO)SPACE ENGINEERING STUDIES IN ITALY IN THE PAST 20 YEARS
The paper presents the evolution and trends in the Master studies in aerospace engineering in Italy, looking at the last 20 years. In the year 2000, a major reform of the higher education in engineering took place in Italy, with the introduction of the so-called âBologna systemâ and the clear separation of Bachelor and Master studies. With this reform, a relatively high flexibility was given to universities to define their program structures. The ministerial rules defined only broad subject areas within which courses and credits should be allocated. This reform allowed to diversify the educational profile within each University and, even more relevant, allowed to create mobility across the country between Bachelor and Master study programs. The paper will show the basic facts and figures in the 6 Italian Universities participating in the PEGASUS network (Politecnico di Milano, Politecnico di Torino, UniversitĂ di Pisa, UniversitĂ degli Studi di Napoli âFederico IIâ, Sapienza UniversitĂ di Roma, Alma Mater Studiorum - UniversitĂ di Bologna), elaborating on the impact of the potential workforce for the sector
The ESA "Plasma Laboratory in Space" study
The European Space Agency has initiated, in the context of its General Studies Programme, a study of the
possible use of space for studies in pure and applied plasma physics, in areas not traditionally covered by âspace plasma physicsâ. A team of experts has been set-up to review a broad range of area including industrial
plasma physics and pure plasma physics, astrophysical and solar-terrestrial areas. A set of experiments have been identified that can potentially provide access to new phenomena and to allow advances in several fields
of plasma science. These experiments concern phenomena on spatial scale (102 to104 m) intermediate between what is achievable on ground experiment and usual solar system plasma observations
Plasma kinetics issues in an ESA study for a plasma laboratory in space
A study supported by the European Space Agency (ESA), in the context of its General Studies Programme, performed an investigation of the possible use of space for studies in pure and applied plasma physics, in areas not traditionally
covered by âspace plasma physicsâ. A set of experiments have been identified that can potentially provide access to new phenomena and to allow advances in several fields of plasma science. These experiments concern phenomena on a
spatial scale (101â104 m) intermediate between what is achievable on the ground and the usual solar system plasma observations. Detailed feasibility studies have been performed for three experiments: active magnetic experiments, largescale discharges and long tetherâplasma interactions. The perspectives opened by these experiments are discussed for magnetic reconnection, instabilities,
MHD turbulence, atomic excited states kinetics, weakly ionized plasmas,plasma diagnostics, artificial auroras and atmospheric studies. The discussion is also supported by results of numerical simulations and estimates
Role of oxidative stress in chronic otitis media with effusion in children
Chronic otitis media with effusion (OME) is a common pathologic condition characterized by nonpurulent fluid in the middle ear (ME) that leads to moderate conductive hearing loss and flat tympanogram. During OME inflammatory cells generate large amounts of superoxide radicals to improve bactericidal activity. Overproduction of oxygen-derived free radicals induces oxidative damage in humans. Glutathione (GSH) is one of the major components of the antioxidant system that protects cells from oxidative stress. The aim of the study was to evaluate oxidative stress in chronic OME by investigation of ME fluids collected during myringotomy. During myringotomy, fluid was collected from the ME to evaluate lipid peroxide levels in the effusion. Immunohistochemical study was also performed to assess the anatomical features of tympanic membrane. Fifty-nine children with ME effusion without any resolution after repeated medical treatments were enrolled in the study. No morphological significant changes were observed. Lipid peroxide levels in all samples were high (mean 11.5 nmole/million cells), similar to the values found in other chronic diseases. GSH might be employed during surgery while applying ventilation tubes and after surgery to prevent oxidative stress. The high oxidant levels in chronic OME observed in our research and the improvement seen in children after antioxidant treatment suggest that oxygen-derived free radicals play an important role in chronic OME.
NextâGeneration Nanopore Sensors Based on Conductive Pulse Sensing for Enhanced Detection of Nanoparticles
Nanopore sensing has been successfully used to characterize biological molecules with single-molecule resolution based on the resistive pulse sensing approach. However, its use in nanoparticle characterization has been constrained by the need to tailor the nanopore aperture size to the size of the analyte, precluding the analysis of heterogeneous samples. Additionally, nanopore sensors often require the use of high salt concentrations to improve the signal-to-noise ratio, which further limits their ability to study a wide range of nanoparticles that are unstable at high ionic strength. Here, a new paradigm in nanopore research that takes advantage of a polymer electrolyte system to comprise a conductive pulse sensing approach is presented. A finite element model is developed to explain the conductive pulse signals observed and compare these results with experiments. This system enables the analytical characterization of heterogeneous nanoparticle mixtures at low ionic strength . Furthermore, the wide applicability of the method is demonstrated by characterizing metallic nanospheres of varied sizes, plasmonic nanostars with various degrees of branching, and protein-based spherical nucleic acids with different oligonucleotide loadings. This system will complement the toolbox of nanomaterials characterization techniques to enable real-time optimization workflow for engineering a wide range of nanomaterials
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