Many studies have reported the occurrence of work-environment contamination by antineoplastic drugs (ANPD), with significant incorporation of trace amounts of these hazardous drugs in hospital ...personnel. Given the ability of most ANPD to actively bind DNA, thus inducing genotoxic effects, it is of pivotal importance to assess the degree of genotoxic damage (i.e., residual genotoxic risk) in occupationally exposed subjects. The lymphocyte cytokinesis-block micronucleus (L-CBMN) assay is largely used for biological effect monitoring in subjects occupationally exposed to ANPD. In this study, we identified and analyzed the studies published reporting the use of the L-CBMN assay as biomarker of genotoxic risk in health care workers exposed to ANPD with the aim of performing meta-analysis and providing a meta-estimate of the genotoxic effect of exposure. We retrieved 24 studies, published from 1988 to 2015, measuring MN in peripheral blood lymphocytes in health care workers occupationally exposed to ANPD. In 15 out of the 24 studies (62.5%), increased MN frequencies were recognized in exposed subjects as compared to controls. The meta-analysis of MN frequency of the combined studies confirmed an association between occupational exposure to ANPD and cytogenetic effects with an overall meta-estimate of 1.67 95% CI: 1.41–1.98. In 16 out of the 24 studies (66.6%) at least one other genotoxicity biomarker, besides L-CBMN assay, was employed for biological effect monitoring. In several studies the effect of exposure to ANPD was evaluated also in terms of MN in exfoliated buccal cells. Other studies focused on genotoxicity endpoints, such as sister chromatid exchanges (3 studies), chromosome aberrations (6 studies), or primary DNA damage investigated by comet assay (7 studies). Overall, there was good agreement between other genotoxicity tests employed and L-CBMN assay outcomes.
The COMPASS RICH-1 detector has undergone a major upgrade in 2016 with the installation of four novel MPGD-based photon detectors. They consist of large-size hybrid MPGDs with multi-layer ...architecture composed of two layers of Thick-GEMs and bulk resistive MicroMegas. A dedicated high voltage power supply system, based on CAEN HV modules, has been built and put in operation: it controls more than 100 HV channels. The system is required to protect the detectors against errors by the operator, monitor voltages and currents at a 1 Hz rate and automatically react to detector misbehavior. It includes also a HV compensation system against environmental pressure and temperature variation to grant the detector stability. The operation of a MPGD based single photon detector poses challenging requirements to the high voltage power supply systems employed in terms of high-resolution diagnostic features and dynamic voltage control. Systems satisfying all the needed features are not commercially available; for this reason a novel single channel high voltage system matching the MPGD needs has been designed and realized. In this article the COMPASS RICH-1 MPGD HV system implementation is described as well as its performance in terms of stability of the novel MPGD-based photon detectors during the physics data taking at COMPASS. The design, implementation and performance of a novel HV power supply system based on DC to DC converters and controlled by a FPGA device is presented. The capabilities of the first prototype of the new single HV channel power supply are illustrated when operated with a MPGD based single photon detector during a test beam exercise. The preliminary result of the multi channel system are briefly discussed.
The next generation of gaseous photon detectors is requested to overcome the limitations of the available technology, in terms of resolution and robustness. The quest for a novel photocathode, ...sensitive in the far vacuum ultra violet wavelength range and more robust than present ones, motivated an R&D programme to explore nanodiamond based photoconverters, which represent the most promising alternative to cesium iodine. A procedure for producing the novel photocathodes has been defined and applied on THGEMs samples. Systematic measurements of the photo emission in different Ar/CH4 and Ar/CO2 gas mixtures with various types of nanodiamond powders have been performed. A comparative study of the response of THGEMs before and after coating demonstrated their full compatibility with the novel photocathodes.
The proposed new Electron–Ion Collider poses a technical and intellectual challenge for the detector design to accommodate the long-term diverse physics goals envisaged by the program. This requires ...a 4π detector system capable of reconstructing the energy and momentum of final state particles with high precision. The Electron-Ion Collider also requires identification of particles of different masses over a wide momentum range.
A diverse spectrum of Particle IDentification detectors has been proposed. Of the four types of detectors for hadron identification, three are based on Ring Imaging Cherenkov Counter technologies, and one is realized by the Time of Flight method. The quest for a novel photocathode, sensitive in the far vacuum ultraviolet wavelength range and more robust than cesium iodide, motivated an R&D programme to explore nano-diamond (ND) based photocathodes, started by a collaboration between INFN and CNR Bari and INFN Trieste. Systematic measurements of the photoemission in different Ar:CH4 and Ar:CO2 gas mixtures with various types of ND powders and Hydrogenated ND (H-ND) powders are reported. A first study of the response of THGEMs coated with different photocathode materials is presented.
The progress of this R&D programme and the results obtained so far by these exploratory studies are described.
After pioneering gaseous detectors of single photon for RICH applications using CsI solid state photocathodes in MWPCs within the RD26 collaboration and by the constructions for the RICH detector of ...the COMPASS experiment at CERN SPS, in 2016 we have upgraded COMPASS RICH by novel gaseous photon detectors based on MPGD technology. Four novel photon detectors, covering a total active area of 1.5m2 have been installed in order to cope with the challenging efficiency and stability requirements of the COMPASS physics programme. They are the first application in an experiment of MPGD-based single photon detectors. All aspects of the upgrade are presented, including engineering, mass production, quality assessment and performance.
Perspectives for further developments in the field of gaseous single photon detectors are also presented.
An upgrade of the near detector of the T2K long baseline neutrino oscillation experiment is currently being conducted. This upgrade will include two new Time Projection Chambers, each equipped with ...16 charge readout resistive Micromegas modules.
A procedure to validate the performance of the detectors at different stages of production has been developed and implemented to ensure a proper and reliable operation of the detectors once installed. A dedicated X-ray test bench is used to characterize the detectors by scanning each pad individually and to precisely measure the uniformity of the gain and the deposited energy resolution over the pad plane. An energy resolution of about 10% is obtained.
A detailed physical model has been developed to describe the charge dispersion phenomena in the resistive Micromegas anode. The detailed physical description includes initial ionization, electron drift, diffusion effects and the readout electronics effects. The model provides an excellent characterization of the charge spreading of the experimental measurements and allowed the simultaneous extraction of gain and charge spreading information of the modules.
Homeless persons can be considered a vulnerable group and several studies showed in this group an higher prevalence of chronic and infectious diseases, a lower mental health status, and a higher ...abuse of alcohol. The aim of our study was to investigate the health status of homeless in Padua, Italy, administering a questionnaire composed by SF-36 and EQ-5D.
We conducted a cross-sectional study from 15 December 2015 to 15 February 2016.
We enrolled in our study 73 homeless persons welcomed in the municipal dorm of Padua. 5 persons refused to participate in the study; 9 had a mental status incompatible with the participation to the study.
We administered to the participants a questionnaire composed by three parts: in the first part we asked sociodemographic information (gender, age, nationality, qualification, height and weight) to calculate BMI, time spent at the dorm, period of homelessness, alcohol intake, smoking habit, availability of a general practitioner, emergency room visits in the last year, admissions in the last year, pre-existing conditions and in act, participation in screening programs. The second part was represented by the Short Form 36 questionnaire. The third part by the EQ-5D questionnaire.
Our sample was composed by 79% men and 21% women. 54.7% were Italian. The mean age was 48 years. 72.8% were smoker and 60,3% drunk alcohol. In this latter group 28.8% drunk more than 1 liter of wine per day. Non Italian homeless smoke less than the Italian: this difference is statistically significant (OR = 3.7 p = 0.032 ). Only 9 foreigners had a general practitioner compared to 30 Italian homeless: this difference is statistically significant (OR = 60 P < 0.01). 43 of the 59 respondents (72.8 % ) said to suffer from some disease. No one reported a history of tuberculosis. The most represented diseases were pneumonia (30%), myocardial infarction (17%), hepatitis C (13.5%). Participation in screening programs was very low. From the analysis of the SF-36 results, homeless persons obtained lower scores than Italian population. In our study, 40 persons reported a level 2 or 3 in the EQ-5D dimension called "anxiety/ depression". In the EQ visual-analogue scale, the homeless population showed a lower perception of its health status.
Compared to the general population, the homeless reported a worse mental health, and this showed that they represent a particularly vulnerable group. Moreover they had a higher percentage of incorrect habits for their health (alcoholism and tobacco addiction), they suffered from chronic conditions, and tended to have a higher frequency of accesses to the emergency rooms. It would be better to improve the state of health of the homeless, through initiatives that could reduce the causes of homelessness, and that could prevent the onset of diseases in this group.
The novel MPGD-based photon detectors of COMPASS RICH-1 consist of large-size hybrid MPGDs with multi-layer architecture including two layers of Thick-GEMs and a bulk resistive MicroMegas. The top ...surface of the first THGEM is coated with a CsI film which also acts as photo-cathode. These detectors have been successfully in operation at COMPASS since 2016. Concerning bias-voltage supply, the Thick-GEMs are segmented in order to reduce the energy released in case of occasional discharges, while the MicroMegas anode is segmented into pads individually biased with positive voltage while the micromesh is grounded. In total, there are about ten different electrode types and more than 20000 electrodes supplied by more than 100 HV channels, where appropriate correlations among the applied voltages are required for the correct operation of the detectors. Therefore, a robust control system is mandatory, implemented by a custom designed software package, while commercial power supply units are used. This sophisticated control system allows to protect the detectors against errors by the operator, to monitor and log voltages and currents at 1 Hz rate, and automatically react to detector misbehavior. In addition, a voltage compensation system has been developed to automatically adjust the biasing voltage according to environmental pressure and temperature variations, to achieve constant gain over time. This development answers to a more general need. In fact, voltage compensation is always a requirement for the stability of gaseous detectors and its need is enhanced in multi-layer ones.
In this paper, the HV system and its performance are described in details, as well as the stability of the novel MPGD-based photon detectors during the physics data taking at COMPASS.
Experiments at the future Electron Ion Collider require excellent hadron identification in a broad momentum range, in harsh conditions. A RICH capable to fulfill the PID requirements of the EIC could ...use MPGD-based photon detectors with solid photocathodes for covering large surfaces at affordable cost, providing good effciency, high resolution and compatibility with magnetic field. Photon detectors realized by coupling THGEMs and Micromegas have been successfully operated at the RICH-1 detector of the COMPASS Experiment at CERN since 2016. A similar technology could be envisaged for an EIC RICH, provided a large improvement in the photon position resolution is achieved. An R&D effort in this direction is ongoing at INFN Trieste. Few prototypes with smaller pixel size (down to 3 mm x 3 mm) have been built and tested in the laboratory with X-Ray and UV LED light sources. A modular mini-pad detector prototype has also been tested at the CERN SPS H4 beamline. New data acquisition and analysis software called Raven DAQ and Raven Decoder have been developed and used with the APV-25 based Scalable Readout System (SRS), for the modular mini-pad prototype tests. The main characteristics of the new mini-pad hybrid MPGD-based detector of single photons are described and preliminary results of laboratory and beam tests are presented.
Abstract
The COMPASS RICH-1 detector underwent major upgrade in 2016 with the installation of four
novel MPGD-based photon detectors. They consist of large-size hybrid MPGDs with multi-layer
...architecture composed of two layers of Thick-GEMs and bulk resistive Micromegas. A dedicated high
voltage power supply system, realized with commercial devices, has been put in operation to
protect the detectors against errors by the operator, monitor and log voltages and currents at a 1 Hz rate, and automatically react to detector misbehavior; it includes also the HV compensation for
the detector gas pressure and temperature variations.
The needs posed to the high voltage
power supply systems by the operation of Micro Pattern Gaseous Detectors pushed the development of
a novel single channel HV system able to overcome the performance of the commercial devices in
terms of high-resolution diagnostic features and intelligent dynamic voltage control. In this talk
the COMPASS HV system and its performance are illustrated, as well as the stability of the novel
MPGD-based photon detectors during the physics data taking at COMPASS. The performance of the
novel single channel power supply system when connected to a single photon Micro Pattern Gaseous
Detector is presented in realistic working condition during a test beam with the preliminary
results of multiple channels operation.
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