50 research outputs found
JRC – Ispra Atmosphere – Biosphere – Climate Integrated monitoring Station : 2011 report
The Institute for Environment and Sustainability provide long-term observations of the atmosphere within international programs and research projects. These observations are performed from the research infrastructure named ABC-IS: Atmosphere-Biosphere-Climate Integrated monitoring station. Most measurements are performed at the JRC-Ispra site. Observations are also carried out from two other platforms: the forest station in San Rossore, and a ship cruising in the Western Mediterranean sea. This document reports about measurement programs, the equipment which is deployed, and the data quality assessment for each site. Our observations are presented, compared to each other, as well as to historical data obtained over the past 25 years at the Ispra site.JRC.H.2-Air and Climat
Learning curve for laparoscopic cholecystectomy has not been defined: A systematic review
Background: Laparoscopic cholecystectomy is one of the most performed surgeries worldwide but its learning curve is still unclear. Methods: A systematic review was conducted according to the 2009 Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Two independent reviewers searched the literature in a systematic manner through online databases, including Medline, Scopus, Embase, and Google Scholar. Human studies investigating the learning curve of laparoscopic cholecystectomy were included. The Newcastle–Ottawa scale for cohort studies and the GRADE scale were used for the quality assessment of the selected articles. Results: Nine cohort studies published between 1991 and 2020 were included. All studies showed a great heterogeneity among the considered variables. Seven articles (77.7%) assessed intraoperative variables only, without considering patient's characteristics, operator's experience, and grade of gallbladder inflammation. Only five articles (55%) provided a precise cut-off value to see proficiency in the learning curve, ranging from 13 to 200 laparoscopic cholecystectomies. Conclusions: The lack of clear guidelines when evaluating the learning curve in surgery, probably contributed to the divergent data and heterogeneous results among the studies. The development of guidelines for the investigation and reporting of a surgical learning curve would be helpful to obtain more objective and reliable data especially for common operation such as laparoscopic cholecystectomy
Source apportionment of PM10 in the Western Mediterranean based on observations from a cruise ship
Abstract Two intensive PM10 sampling campaigns were performed in the summers of 2009 and 2010 on the ship Costa Pacifica during cruises in the Western Mediterranean. Samples, mainly collected on an hourly basis, were analysed with different techniques (Particle Induced X-Ray Emission, PIXE; Energy Dispersive - X Ray Fluorescence, ED-XRF; Ion Chromatography, IC; Thermo-optical analysis) to retrieve the PM10 composition and its time pattern. The data were used for obtaining information about the sources of aerosol, with a focus on ship emissions, through apportionment using chemical marker compounds, correlation analysis and Positive Matrix Factorization (PMF) receptor modelling. For the campaign in 2010, 66% of the aerosol sulphate was found to be anthropogenic, only minor contributions of dust and sea salt sulphate were observed while the biogenic contribution, estimated based on the measurements of MSA, was found to be more important (26%), but influenced by large uncertainties. V and Ni were found to be suitable tracers of ship emissions during the campaigns. Four sources of aerosol were resolved by the PMF analysis; the source having the largest impact on PM10, BC and sulphate was identified as a mixed source, comprising emissions from ships. The correlations between sulphate and V and Ni showed the influence of ship emissions on sulphate in marine air masses. For the leg Palma–Tunis crossing a main ship route, the correlations between aerosol sulphate and V and Ni were particularly strong (r2 = 0.9 for both elements)
Impact of maritime traffic on polycyclic aromatic hydrocarbons, metals and particulate matter in Venice air
Harbours are important hubs for economic growth in both tourism and commercial activities. They are also an environmental burden being a source of atmospheric pollution often localized near cities and industrial complexes. The aim of this study is to quantify the relative contribution of maritime traffic and harbour activities to atmospheric pollutant concentration in the Venice lagoon. The impact of ship traffic was quantified on various pollutants that are not directly included in the current European legislation for shipping emission reduction: (i) gaseous and particulate PAHs; (ii) metals in PM10; and (iii) PM10 and PM2.5. All contributions were correlated with the tonnage of ships during the sampling periods and results were used to evaluate the impact of the European Directive 2005/33/EC on air quality in Venice comparing measurements taken before and after the application of the Directive (year 2010). The outcomes suggest that legislation on ship traffic, which focused on the issue of the emissions of sulphur oxides, could be an efficient method also to reduce the impact of shipping on primary particulate matter concentration; on the other hand, we did not observe a significant reduction in the contribution of ship traffic and harbour activities to particulate PAHs and metals
Progress and perspectives in the low-energy kaon-nucleon/nuclei interaction studies at the DAΦNE collider
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Communication Challenges in Providing Advance Care Planning for People Living With HIV/AIDS
ANGUS: A multichannel CMOS circuit for large capacitance silicon photomultiplier detectors for SPECT applications
Clinical SPECT/MRI applications based on indirect conversion require the use of large area solid-state detectors. Silicon Photomultiplier (SiPM) is a fast-improving technology suitable for this application, due to its compatibility with the MRI environment and to its high multiplication gain. Considering the large number of detectors of a SPECT ring, a multichannel ASIC is needed to have a compact readout. SiPMs have a large specific output capacitance (approx. 200 pF·mm-2), which can result in a load of several nanofarad for each pixel at the input of the readout circuit. We developed ANGUS, a 36-channel 0.35 μm CMOS technology ASIC designed to cope with input capacitances larger than 10 nF, with an overall power dissipation of 400 mW. A current mode input is used, allowing an input voltage tuning for SiPM overvoltage regulation in a 1 V range. A programmable RC filter is used to extract the signal amplitude information. The implemented time constants make the chip suitable for use with various type of scintillator crystal (e.g. CsI:Tl, GaGG:Ce, LYSO:Ce, NaI:Tl). Room temperature energy resolution measurements performed with ANGUS employing SiPM from FBK and Hamamatsu coupled to CsI:Tl crystals with a 57Co source are reported in the following. 12% FWHM resolution was measured at the 122 keV line of this source using FBK detectors
MARC: A fast current-readout CMOS front-end for n-substrate, fully-depleted scientific CCDs
A 12-bit charge-redistribution SAR ADC for silicon drift detector readout ASICs
This paper presents a first prototype of a 12-bit analog-to-digital converter (ADC) suitable for X and γ-ray multichannel readout front-ends for SDD signals processing. The task of the converter is the digitization of output multiplexed data at a sampling frequency up to 5 MS/s and about 11-bit accuracy. The chosen architecture is the fully-differential bridge-capacitor charge-redistribution (CR) successive-approximation-register (SAR) with monotonic switching algorithm. The chip is fabricated in a standard CMOS 0.35 μm 3.3 V technology and the ADC area occupancy is 0.42 mm2. The measured input-output characteristic shows monotonicity over the whole dynamic range while static parameters are -0.17/1.22 LSB and -2.2/2.2 LSB respectively for differential (DNL) and integral nonlinearity (INL). Dynamic performance consist in 68 dB SFDR, 66.5 dB SiNAD and an effective number of bits (ENOB) equal to 10.75 at 4 MS/s. An in-depth analysis of the circuit topology together with simulated and experimental results are here presented
