359 research outputs found
HBIM FOR THE SEISMIC VULNERABILITY ASSESSMENT OF TRADITIONAL BELL TOWERS
Abstract. The research proposes a novel and expeditious approach starting from direct and SfM (Structure from Motion) surveying up to H-BIM to provide a supporting tool to the knowledge of traditional bell towers, also useful for the seismic vulnerability assessment. The research draws on the possibility to enrich the H-BIM model with a semantic layer that takes into account the vulnerability indicators as defined in 2011 Italian Guidelines for the assessment and reduction of seismic risk of cultural heritage. Starting from 3D data survey, passing through the historical and constructive analysis, and the semantic classification of parts, the workflow foresaw the setting up of a semantic layer creating parameters to be assigned to each architectural component of the building and according an expeditious check-list which focuses on empirical knowledge of bell towers. This kind of information stored in the model could be very useful in situations that require particularly timely decision-making, such as in the case of calamitous events
Room temperature evolution of gold nanodots deposited on silicon
In this work, the morphological and structural evolution of gold nanodots deposited on Si substrates has been monitored for 2.4 × 103 h. Gold nanodots on Si are of great scientific interest because they can be used in numerous ways, for example as subwavelength antennas in plasmonics, as electrical contacts in nanometric devices, or as catalysts for the formation of quasi-1dimensional nanostructures. Their characteristics have been studied in a very large number of papers in literature, and among the several aspects, it is known that continuous Au films peculiarly interact with Si by interdiffusion even at room temperature. It would be expected that also small nanostructures could undergo to an interdiffusion and consequent modifications of their structure and shape after aging. Despite the cruciality of this topic, no literature papers have been found showing a detailed morphological and structural characterization of aged Au nanodots. Au nanoparticles have been deposited by sputtering on Si and stored in air at temperature between 20 and 23 °C and humidity of about 45 %, simulating the standard storage conditions of most of the fabrication labs. The morphological and structural characterizations have been performed by bright field transmission electron microscopy (TEM). A specific procedure has been used in order to avoid any modification of the material during the specimen preparation for the TEM analysis. A digital processing of the TEM images has allowed to get a large statistical analysis on the particles size distribution. Two different types of nanoparticles are found after the deposition: pure gold crystalline nanodots on the Si surface and gold amorphous nanoclusters interdiffused into the Si subsurface regions. While the nanodots preserve both morphology and structure all over the time, the amorphous agglomerates show an evolution during aging in morphology, structure, and chemical phase
Isothiazole derivatives as antiviral agents
We recently described the synthesis and antiviral activity of the compounds 5-phenyl-3-(4-cyano-5-phenylisothiazol-3-yl) disulphanyl-4-isothiazole-carbonitrile and S-(4-cyano-5-phenylisothiazol-3-yl)- O-ethyl thiocarbonate, which were found to be effective against both HIV-1 (IIIB) and HIV-2 (ROD). We have now evaluated these compounds against both RNA and DNA viruses, obtaining high selectivity indexes for poliovirus 1 (SI: 223 and 828, respectively) and Echovirus 9 (SI: 334 and 200, respectively). In our previous studies, 3-methylthio-5-(4- OBn-phenyl)-4-isothiazolecarbo-nitrile was found to exhibit a broad spectrum of action against picornaviruses, we therefore selected this compound and S-(4-cyano-5-phenylisothiazol-3-yl)- O-ethyl thiocarbonate as the model for the synthesis of a new isothiazole derivative, S-[4-cyano-5-(4- OBn-phenyl)isothiazol-3-yl]- O-ethyl thiocarbonate. This compound was evaluated against picornaviruses, measles virus, HIV-1 (IIIB) and HIV-2 (ROD), and some DNA viruses (adenovirus type 2 and herpes simplex virus type 1). The compound was shown to be active against rhinoviruses 2, 39, 86 and 89, Coxsackie B1 and measles virus
Muon calibration of the ASTRI-Horn telescope: preliminary results
Astri-Horn is a Small-Sized Telescope (SST) for very-high energy gamma-ray
astronomy installed in Italy at the INAF "M.C. Fracastoro" observing station
(Mt. Etna, Sicily). The ASTRI-Horn telescope is characterized by a dual-mirror
optical system and a curved focal surface covered by SiPM sensors managed by a
innovative fast front-end electronics. Dedicated studies were performed to
verify the feasibility of the calibration through muons on the relatively small
size of the primary mirror (~4 m diameter), as in the case of larger Cherenkov
telescopes. A number of tests were performed using simulations of the
atmospheric showers with the CORSIKA package and of the telescope response with
a dedicated simulator. In this contribution we present a preliminary analysis
of muon events detected by ASTRI-Horn during the regular scientific data taking
performed in December 2018 and March 2019. These muon events validate the
results obtained with the simulations and definitively confirm the feasibility
of calibrating the ASTRI-Horn SST telescope with muons.Comment: Proceedings of the 36th International Cosmic Ray Conference, Madison,
Wisconsin, USA, 24 July-1 August 201
A study of methyl formate in astrochemical environments
Several complex organic molecules are routinely detected in high abundances
towards hot cores and hot corinos. For many of them, their paths of formation
in space are uncertain, as gas phase reactions alone seem to be insufficient.
In this paper, we investigate a possible solid-phase route of formation for
methyl formate (HCOOCH3). We use a chemical model updated with recent results
from an experiment where simulated grain surfaces were irradiated with 200 keV
protons at 16 K, to simulate the effects of cosmic ray irradiation on grain
surfaces.
We find that this model may be sufficient to reproduce the observed methyl
formate in dark clouds, but not that found in hot cores and corinos.Comment: 6 pages, 2 figures, 2 tables Accepted by MNRA
Maintaining good practice in breast cancer management and reducing the carbon footprint of care: study protocol and preliminary results
Objective: Health care accounts for up to 8-10% of greenhouse emission yearly in the US and surgical room contributes an estimated 25-30% of hospital waste. Despite the major role of greenhouse emissions because of surgery, little has been done by surgeons to reduce their impact. In this paper, we present a multicentric retrospective analysis to evaluate the carbon footprint of the most common breast surgical treatment and a preliminary analysis of our results.
Patients and Methods: Retrospective analysis with processed-based life cycle assessment (LCA) has been obtained to determine carbon footprint of different surgical procedures. In our preliminary study, we enrolled all consecutive patients undergoing breast conserving procedure (BCP) between 9th March 2019 and 9th March 2021 to underline the reduction in fuel consumption with postoperative telehealth application (pre-COVID-19 vs. COVID-19). A propensity score matching was implemented to optimize comparability.
Results: From 276 BCP patients, PSM included 69 pre-COVID-19 and 69 COVID-19 groups, respectively. No statistically significant difference was found in the tumor stage, marital status, and distance from the hospital. A total of 466 postoperative visits was performed and a statistically significant difference in telehealth visit rate was found between groups (1.75% vs. 51.68%; p<0.001). A reduction of 4312.38 km in travel to the hospital was found in the COVID-19 group. No difference was found in postoperative complications.
Conclusions: Health systems worldwide are implementing zero-carbon programs to reduce their carbon footprint. Breast surgeons should consider the consequences of their actions and embrace the pillars of the circular economy. Our data could promote further action in order to raise awareness regarding carbon footprint of breast surgery
The effects of methanol on the trapping of volatile ice components
The evaporation of icy mantles, which have been formed on the surface of dust grains, is acknowledged to give rise to the rich chemistry that has been observed in the vicinity of hot cores and corinos. It has long been established that water ice is the dominant species within many astrophysical ices. However, other molecules found within astrophysical ices, particularly methanol, can influence the desorption of volatile species from the ice. Here we present a detailed investigation of the adsorption and desorption of methanol-containing ices, showing the effect that methanol has on the trapping and release of volatiles from model interstellar ices. OCS and CO2 have been used as probe molecules since they have been suggested to reside in water-rich and methanol-rich environments. Experiments show that methanol fundamentally changes the desorption characteristics of both OCS and CO2, leading to the observation of mainly codesorption of both species with bulk water ice for the tertiary ices and causing a lowering of the temperature of the volcano component of the desorption. In contrast, binary ices are dominated by standard volcano desorption. This observation clearly shows that codepositing astrophysically relevant impurities with water ice, such as methanol, can alter the desorption dynamics of volatiles that become trapped in the pores of the amorphous water ice during the sublimation process. Incorporating experimental data into a simple model to simulate these processes on astrophysical timescales shows that the additional methanol component releases larger amounts of OCS from the ice mantle at lower temperatures and earlier times. These results are of interest to astronomers as they can be used to model the star formation process, hence giving information about the evolution of our Universe
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