1,331 research outputs found
Letter: chronic hepatitis C genotype 3 infection - still a hurdle toward a direct-acting anti-viral-induced HCV cure?
Letter: chronic hepatitis C genotype 3
infection â still a hurdle toward a
direct-acting anti-viral-induced HCV cur
Analysis of short-term blood pressure variability in pheochromocytoma/paraganglioma patients
Data on short-term blood pressure variability (BPV), which is a well-established cardiovascular prognostic tool, in pheochromocytoma and paraganglioma (PPGL) patients is still lack and conflicting. We retrospectively evaluated 23 PPGL patients referred to our unit from 2010 to 2019 to analyze 24 h ambulatory blood pressure monitoring (24-h ABPM)-derived markers of short-term BPV, before and after surgical treatment. PPGL diagnosis was assessed according to guidelines and confirmed by histologic examination. The 24-h ABPM-derived markers of short-term BPV included: circadian pressure rhythm; standard deviation (SD) and weighted SD (wSD) of 24-h, daytime, and night-time systolic and diastolic blood pressure (BP); average real variability (ARV) of 24-h, daytime, and night-time systolic and diastolic BP. 7 males and 16 females of 53 ± 18 years old were evaluated. After surgical resection of PPGL we found a significant decrease in 24-h systolic BP ARV (8.8 ± 1.6 vs. 7.6 ± 1.3 mmHg, p < 0.001), in 24-h diastolic BP ARV (7.5 ± 1.6 vs. 6.9 ± 1.4 mmHg, p = 0.031), and in wSD of 24-h diastolic BP (9.7 ± 2.0 vs 8.8 ± 2.1 mmHg, p = 0.050) comparing to baseline measurements. Moreover, baseline 24-h urinary metanephrines significantly correlated with wSD of both 24-h systolic and diastolic BP. Our study highlights as PPGL patients, after proper treatment, show a significant decrease in some short-term BPV markers, which might represent a further cardiovascular risk factor
Computational approaches to shed light on molecular mechanisms in biological processes
Computational approaches based on Molecular Dynamics simulations, Quantum Mechanical methods and 3D Quantitative Structure-Activity Relationships were employed by computational chemistry groups at the University of Milano-Bicocca to study biological processes at the molecular level. The paper reports the methodologies adopted and the results obtained on Aryl hydrocarbon Receptor and homologous PAS proteins mechanisms, the properties of prion protein peptides, the reaction pathway of hydrogenase and peroxidase enzymes and the defibrillogenic activity of tetracyclines. © Springer-Verlag 2007
CHANTI: a Fast and Efficient Charged Particle Veto Detector for the NA62 Experiment at CERN
The design, construction and test of a charged particle detector made of
scintillation counters read by Silicon Photomultipliers (SiPM) is described.
The detector, which operates in vacuum and is used as a veto counter in the
NA62 experiment at CERN, has a single channel time resolution of 1.14 ns, a
spatial resolution of ~2.5 mm and an efficiency very close to 1 for penetrating
charged particles
Tip-to-base conduit widening remains consistent across cambial age and climates in Fagus sylvatica L
: Water transport, mechanical support and storage are the vital functions provided by the xylem. These functions are carried out by different cells, exhibiting significant anatomical variation not only within species but also within individual trees. In this study, we used a comprehensive dataset to investigate the consistency of predicted hydraulic vessel diameter widening values in relation to the distance from the tree apex, represented by the relationship Dh â LÎČ (where Dh is the hydraulic vessel diameter, L the distance from the stem apex and ÎČ the scaling exponent). Our analysis involved 10 Fagus sylvatica L. trees sampled at two distinct sites in the Italian Apennines. Our results strongly emphasize that vessel diameter follows a predictable pattern with the distance from the stem apex and ÎČ ~ 0.20 remains consistent across cambial age and climates. This finding supports the hypothesis that trees do not alter their axial configuration represented by scaling of vessel diameter to compensate for hydraulic limitations imposed by tree height during growth. The study further indicates that within-tree variability significantly contributes to the overall variance of the vessel diameter-stem length exponent. Understanding the factors that contribute to the intraindividual variability in the widening exponent is essential, particularly in relation to interspecific responses and adaptations to drought stress
A prototype large-angle photon veto detector for the P326 experiment at CERN
The P326 experiment at the CERN SPS has been proposed with the purpose of
measuring the branching ratio for the decay K^+ \to \pi^+ \nu \bar{\nu} to
within 10%. The photon veto system must provide a rejection factor of 10^8 for
\pi^0 decays. We have explored two designs for the large-angle veto detectors,
one based on scintillating tiles and the other using scintillating fibers. We
have constructed a prototype module based on the fiber solution and evaluated
its performance using low-energy electron beams from the Frascati Beam-Test
Facility. For comparison, we have also tested a tile prototype constructed for
the CKM experiment, as well as lead-glass modules from the OPAL electromagnetic
barrel calorimeter. We present results on the linearity, energy resolution, and
time resolution obtained with the fiber prototype, and compare the detection
efficiency for electrons obtained with all three instruments.Comment: 8 pages, 9 figures, 2 tables. Presented at the 2007 IEEE Nuclear
Science Symposium, Honolulu HI, USA, 28 October - 3 November 200
SARS-CoV-2 and companion animals: sources of information and communication campaign during the COVID-19 pandemic in Italy
This study analyzed data on the sources and the level of Italiansâ awareness on the risk of infection by SARS-CoV-2 at the humanâanimal interface. Data were collected through a survey-type investigation on a representative sample of the Italian population. Forty-five percent of the interviewees were aware that companion animals could be infected by SARS-CoV-2. However, 29.8% were familiar with preventive measures to adopt to avoid viral transmission between infected humans and companion animals, and only 20.7% knew which companion animals could be at risk of infection. Higher awareness regarding the risk of SARS-CoV-2 transmission between animals and humans (51.7%) and the measures to prevent it (33.3%) was detected among companion animalsâ owners. Notably, 40.4% of interviewees were not informed at all. Television broadcasts (26.4%) represented the main source of information, while only 3.5% of the interviewees relied on veterinarians, of which 31.9% considered this source of information as the most trustworthy. Overall, 72.4% of Italians recognized that the communication campaign on COVID-19 and companion animals was inadequate. This survey highlights the need for increasing the public awareness of the risk of companion animals being infected with SARS-CoV-2 and the involvement of professionals in the public communication on zoonoses. © 2023 by the authors
A new cylindrical borehole detector for radiographic imaging with muons
Muon radiography is a methodology which enables measuring the mass distribution within large objects. It exploits the abundant flux of cosmic muons and uses detectors with different technologies depending on the application. As the sensitive surface and geometric acceptance are two fundamental parameters for increasing the collection of muons, the optimization of the detectors is very significant. Here we show a potentially innovative detector of size and shape suitable to be inserted inside a borehole, that optimizes the sensitive area and maximizes the angular acceptance thanks to its cylindrical geometry obtained using plastic arc-shaped scintillators. Good spatial resolution is obtained with a reasonable number of channels. The dimensions of the detector make it ideal for use in 25Â cm diameter wells. Detailed simulations based on Monte Carlo methods show great cavity detection capability. The detector has been tested in the laboratory, achieving overall excellent performance
Clinical Performance of the Automated LIAISONÂź Meridian H. pylori SA Stool Antigen Test
Background. Antigens derived from Helicobacter pylori can be used as stool biomarkers to assist in the diagnosis of H. pylori infection. Since current assays have variable performance, we assessed the clinical performance of the automated LIAISONÂź Meridian H. pylori SA chemiluminescent immunoassay against more invasive biopsy tests that are considered to be the "gold standard" (Composite Reference Method). Methods. This prospective multisite study enrolled patients undergoing an esophagogastroduodenoscopy with collection of biopsy and stool specimens. Adult patients (â„22 years) participated in the study from February 2017 to August 2018. Specimens of the stomach were tested by three methods, known as the Composite Reference Method: (1) histological evaluation, (2) culture of the organism, and (3) rapid urease detection test. H. pylori in stool was detected using the automated LIAISONÂź Meridian H. pylori SA assay, a chemiluminescent immunoassay. Statistical analyses were performed using MedCalc 18.11.6. Results. 277 patients (63% female) were included in the study. The prevalence of infected subjects was 24.2% in this study cohort. Clinical performance assessed against the Composite Reference Method showed very good agreement (Cohen's kappa=0.922), with good sensitivity (95.5%) and specificity (97.6%). Reproducibility study results showed total imprecision ranging from 3.1% to 13.9% CV. Conclusion. The automated LIAISONÂź Meridian H. pylori SA assay brings reliable noninvasive testing for H. pylori to the laboratory that is in very good agreement with the current, more invasive biopsy-based methods such as histology, culture, or rapid urease test. The clinical trial identifiers are NCT03060746 (pretherapy) and NCT03060733 (posttherapy)
A panchromatic view of the bulge globular cluster NGC 6569
We used high-resolution optical HST/WFC3 and multi-conjugate adaptive optics
assisted GEMINI GeMS/GSAOI observations in the near-infrared to investigate the
physical properties of the globular cluster NGC 6569 in the Galactic bulge. We
have obtained the deepest purely NIR color-magnitude diagram published so far
for this cluster using ground-based observations, reaching
21.0 mag (two magnitudes below the main-sequence turn-off point). By combining
the two datasets secured at two different epochs, we determined relative proper
motions for a large sample of individual stars in the center of NGC 6569,
allowing a robust selection of cluster member stars. Our proper motion analysis
solidly demonstrates that, despite its relatively high metal content, NGC 6569
hosts some blue horizontal branch stars. A differential reddening map has been
derived in the direction of the system, revealing a maximum color excess
variation of about 0.12 mag in the available field of
view. The absolute age of NGC 6569 has been determined for the first time. In
agreement with the other few bulge globular clusters with available age
estimates, NGC 6569 turns out to be old, with an age of about 12.8 Gyr, and a
typical uncertainty of 0.8-1.0 Gyr.Comment: 25 pages, 16 Figures, 1 Table. Accepted for publication in Ap
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