Hospital-acquired infections pose an ongoing threat to patient safety due to the presence of multi-drug resistant organisms (MDROs) and other pathogens such as Clostridioides difficile which are ...dependent on thorough and effective cleaning and disinfection by personnel.
This study evaluates the influence of UV-C air treatment because the air in the room had been sanitized by UV-C and redirected into the room. Moreover, ozone was released into the room to treat actual surfaces in Low-Risk Areas such as hospital gyms, and High-Medium risk areas such as hospital rooms. To this aim, a portable device designed for treating the environment air was tested against nine bacterial strains including Aspergillus spp. and Clostridioides spp. The use of UV-C air treatment during daily operations and ozone treatment achieved at least a 2-log10 pathogen reduction except for Clostridioides spp. Effective prevention of Clostridioides difficile normally requires the use of combined approaches that include chemical compounds and disinfection agents whose toxicity can be harmful not only to patients but also to healthcare personnel. Thus, the proposed no-touch device may be evaluated in future research to assess the needed requirements for its possible and full implementation in hospitals.
The cylindrical drift chamber is the most innovative part of the MEG II detector, the upgraded version of the MEG experiment. The MEG II chamber differs from the MEG one because it is a single volume ...cylindrical structure, instead of a segmented one, chosen to improve its resolutions and efficiency in detecting low energy positrons from muon decays at rest. In this paper, we show the characteristics and performances of this fundamental part of the MEG II apparatus and we discuss the impact of its higher resolution and efficiency on the sensitivity of the MEG II experiment. Because of its innovative structure and high quality resolution and efficiency the MEG II cylindrical drift chamber will be a cornerstone in the development of an ideal tracking detector for future positron-electron collider machines.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract The tailings dump of Barraxiutta (Sardinia, Italy) contains considerable concentrations of heavy metals and, consequently, is scarcely colonized by plants. However, wild populations of the ...liverwort Lunularia cruciata (L.) Dum. form dense and healthy‐looking carpets on this tailing dump. L. cruciata colonizing the tailing dump was compared with a control population growing in a pristine environment in terms of: (i) pollutant content, (ii) photochemical efficiency, and (iii) volatile secondary metabolites in thalli extracts. L. cruciata maintained optimal photosynthesis despite containing considerable amounts of soil pollutants in its thalli and had higher sesquiterpene content compared to control plants. Sesquiterpenes have a role in plant stress resistance and adaptation to adverse environments. In the present study, we propose enhanced sesquiterpenes featuring Contaminated L. cruciata as a defence strategy implemented in the post‐mining environment.
The MEG II experiment, based at the Paul Scherrer Institut in Switzerland, reports the result of a search for the decay
μ
+
→
e
+
γ
from data taken in the first physics run in 2021. No excess of ...events over the expected background is observed, yielding an upper limit on the branching ratio of
B
(
μ
+
→
e
+
γ
)
<
7.5
×
10
-
13
(90% CL). The combination of this result and the limit obtained by MEG gives
B
(
μ
+
→
e
+
γ
)
<
3.1
×
10
-
13
(90% CL), which is the most stringent limit to date. A ten-fold larger sample of data is being collected during the years 2022–2023, and data-taking will continue in the coming years.
Few data are available on adverse events (AE) associated to vaccines in persons with multiple sclerosis (pwMS).
to study the incidence of acute phase AE (AP-AE) related to SARS-CoV-2 mRNA vaccines in ...pwMS compared to a control group, and to analyze the association between AP-AE and disease modifying treatments (DMT).
This was a cross-sectional study on 438 PwMS and 481 age- and sex-matched subjects not affected by dysimmune diseases that underwent two doses of SARS-CoV-2 mRNA BNT162b2 vaccine (Pfizer/BioNtech).
Two hundred and twenty five (51.4%) pwMS complained of ≥1 AP-AE after the first dose, 269 (61.4%) after the second dose. A logistic regression analysis revealed that only pwMS on Fingolimod and Ocrelizumab did not show a higher risk of developing AP-AE. The likelihood to present with ≥1 AP-AE, after correcting for age and sex, was significantly higher in pwMS than controls.
This study reports qualitative and quantitative features of AP-AE associated with the first and second doses of SARS-CoV-2 vaccine in a large sample of pwMS. The only risk factor identified for developing AP-AE is female gender. AntiCD-20 monoclonal antibodies and S1P inhibitors are associated with a lower risk of AP-AE occurrence.
Abstract
Ultra-thin metallic anode and cathode wires are frequently
employed in low-mass gaseous detectors for precision experiments,
where the amount of material crossed by charged particles must be
...minimised. We present here the results of an analysis of the
mechanical stress and chemical corrosion effects observed in 40
and 50 μm diameter silver plated aluminum wires
mounted within the volume of the MEG II drift chamber, which caused
the breakage of about one hundred wires (over a total of
≈ 12000). This analysis is based on the careful inspection
of the broken wires by means of optical and electronic microscopes
and on a detailed recording of all breaking incidents. We present a
simple empirical model which relates the number of broken wires to
their exposure time to atmospheric relative humidity and to their
mechanical tension, which is necessary for mechanical stability in
the presence of electrostatic fields of several kV/cm. Finally we
discuss how wire breakages can be avoided or at least strongly
reduced by operating in controlled atmosphere during the mounting
stages of the wires within the drift chamber and by choosing a
25 % thicker wire diameter, which has very small effects on the
detector resolution and efficiency and can be obtained by using a
safer fabrication technique.
The Cylindrical Drift Chamber of the MEG II experiment Chiappini, M.; Baldini, A.M.; Benmansour, H. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2023, Letnik:
1047
Journal Article
Recenzirano
The MEG experiment at the Paul Scherrer Institut (PSI) represents the state of the art in the search for the charged Lepton Flavor Violating μ+→e+γ decay, setting the most stringent upper limit on ...the BR (μ+→e+γ)≤4.2×10−13 (90% C.L.). An upgrade of MEG, MEG II, was designed, commissioned and recently started the physics data taking. Its goal is to reach a sensitivity level of 6×10−14. In order to reconstruct the positron momentum vector a Cylindrical Drift CHamber (CDCH) with unprecedented peculiarities was built, featuring angular and momentum resolutions at the 6.5 mrad and 100 keV/c level. The CDCH is a 2-meter long, 60 cm in diameter, low-mass, single volume detector with high granularity: 9 layers of 192 drift cells, few mm wide, defined by ∼12000 wires in a stereo configuration for longitudinal hit localization. The filling gas mixture is Helium:Isobutane 90:10. The total radiation length is 1.5×10−3 X0, thus minimizing the Multiple Coulomb Scattering and allowing for a single-hit resolution <120μm. After the assembly at INFN Pisa, the CDCH was transported to PSI and integrated into the MEG II experimental apparatus since 2018. The commissioning phase lasted for the past three years until the operational stability was reached in 2020. The analysis software is continuously developing and the tuning of the reconstruction algorithms is one of the main activities. The latest updates on the positron momentum vector resolutions and tracking efficiency are presented.
Operation and performance of the MEG II detector Afanaciev, K.; Baldini, A. M.; Ban, S. ...
The European physical journal. C, Particles and fields,
02/2024, Letnik:
84, Številka:
2
Journal Article
Recenzirano
Odprti dostop
The MEG II experiment, located at the Paul Scherrer Institut (PSI) in Switzerland, is the successor to the MEG experiment, which completed data taking in 2013. MEG II started fully operational data ...taking in 2021, with the goal of improving the sensitivity of the
μ
+
→
e
+
γ
decay down to
∼
6
×
10
-
14
almost an order of magnitude better than the current limit. In this paper, we describe the operation and performance of the experiment and give a new estimate of its sensitivity versus data acquisition time.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
9.
Commissioning and preliminary performance of the MEG II drift chamber Chiappini, M.; Chiarello, G.; Baldini, A.M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
10/2022, Letnik:
1041
Journal Article
Recenzirano
In the quest for Lepton Flavor Violation (LFV) the MEG experiment at the Paul Scherrer Institut (PSI) represents the state of the art in the search for the charged LFV decay μ+→e+γ, setting the most ...stringent upper limit on the BR(μ+→e+γ)≤4.2×10−13 (90% C.L.). An upgrade of MEG, MEG II, was designed and it recently started the physics data taking, with the aim to reach a sensitivity level of 6×10−14. The Cylindrical Drift CHamber (CDCH) is a key detector in order to improve the e+ angular and momentum resolutions at the 6.5 mrad and 100 keV/c level. The CDCH is a low-mass single volume detector with high granularity: 9 layers of 192 drift cells each, few mm wide, defined by 12000 wires in a stereo configuration for longitudinal hit localization. After the assembly, the CDCH was transported to PSI for the commissioning phase and it has been integrated into the MEG II experimental apparatus since 2018. The operational stability was reached in 2020 and the complete readout electronics was tested for the first time in 2021. A preliminary analysis of 2020–2021 data is presented.
Drypetes klainei Pierre ex Pax is used in Cameroon by Baka Pygmies in the wound healing process and for the treatment of burns.
To validate the traditional use of D. klainei Pierre ex Pax stem bark ...extracts through the evaluation of their antimicrobial properties and their ability to improve wound healing process in fibroblast cell cultures.
The antimicrobial properties of D. klainei extracts were evaluated against Staphylococcus aureus ATCC 6538, Streptococcus pyogenes ATCC 19615, Escherichia coli ATCC 10536, Candida albicans ATCC 10231, on the basis of the minimum inhibitory concentration (MIC) and the minimum bactericidal–fungicidal concentration (MBC–MFC) by the macrodilution method. The extracts abilities to accelerate wound healing were studied on murine and human fibroblasts in terms of cell viability and migration (scratch wound-healing assay).
All the extracts were non-toxic against the selected microorganisms at the tested concentrations, and significantly improve wound healing process in vitro, compared to untreated controls. However, the defatted methanol extract was active at lower concentrations, compared to the water extract.
The ability of both water and defatted methanol extracts to accelerate scratch wound closure in fibroblast cultures may support the traditional use of D. klainei stem bark in the treatment of skin lesions (such as burns) even if no antimicrobial activity was evidenced.
This study supports the traditional use of D. klainey stem bark in the treatment of skin lesions (such as burns) thanks to the ability of both water (WE) and defatted methanol (DME) extracts to accelerate scratch wound closure in fibroblast cultures
Display omitted
PDF
