BACKGROUND: Multiple sclerosis (MS) as an auto-immune disease is an inflammatory, demyelinating disease of the central nervous system. Certain genes have shown to be involved in the initiation of MS ...but the specific role of some of them, e.g. IFNAR1 has not been identified in certain populations yet. OBJECTIVE: The IFNAR1 as a type I membrane protein shapes one of the two chains of a receptor for interferons alpha and beta. METHODS: To find out how IFNAR1 functions in the Iranian population, the researchers compared the expression level of this gene in relapsing-remitting MS (RR-MS) samples with normal individuals. RNA from the whole blood of 50 RR-MS patients and 50 normal controls were extracted. All patients were HLA-DRB1*15 negative and were responders to interferon-beta with a normal vitamin D level. The level of IFNAR1 gene expression was measured using quantitative RT-PCR. RESULTS: According to the results the RR-MS patients manifested a statistically higher expression level of IFNAR1 than their normal counterparts (p= 0.012). Age-wise, females between the ages, 30 to 40 had a significant increase (p= 0.046) but males under 30 showed a statistically meaningful decrease in the expression level (p= 0.04). In terms of sex, only the female patients manifested a statistically significant increase in IFNAR1 (p= 0.004). CONCLUSIONS: The overall results show an increase in IFNAR1 level in MS patients treated with IFN-B.
The exclusive production of charged pions, are reported in the proton-proton collisions, where the π+π- pair is emitted at the central rapidity, y, and the scattered protons stay intact (p) without ...detection. This measurement is performed with the CMS detector at the LHC, using a data sample corresponding to an integrated luminosity of 450 μb-1 collected at a center-of-mass energy of 7 TeV. The dipion cross section, measured for single-pion transverse momentum pT > 0.2 GeV/c and rapidity |y| < 2, is 20.5 ± 0.3 (stat) ± 3.1 (syst) ± 0.8 (lumi) μb. The differential cross sections as a function of π+π- invariant mass, is compared to phenomenological predictions.
SiPMs operate in Geiger mode, wherein photodiode cells are reverse-biased to the breakdown by even a single photon. Each cell is connected in series with a quenching resistor, which prevents cell ...damage and resets the cell after making a signal. All cells are arranged in parallel, making SiPMs and biasing circuits vulnerable to over-illumination, where the current passing through the SiPM can exceed the allowable value, leading to damage. In this study, we investigate over-current conditions in SiPMs and propose a protective method against over-illumination and over-current using a series resistor. Additionally, we ensure SiPM stability through the incorporation of a suitable capacitor.
We report a measurement of the exclusive production of pairs of charged pions in proton-proton collisions, dominated by the process \(pp \rightarrow p^{(*)} \pi^{+}\pi^{-} p^{(*)}\), where \(\rm ...p^{(*)}\) stands for a diffractively dissociated proton, the \(\pi^{+} \pi^{-}\) pair is emitted at central rapidities \(y\), and the incident protons stay intact or dissociate without detection \({\rm p^{(*)}}\). The measurement is performed with the CMS detector at the LHC, using a data sample corresponding to an integrated luminosity of 450~\(\mu\)b\(^{-1}\) collected at a center-of-mass energy of \(\sqrt{s}\) = 7 TeV in 2010. The cross section measured in the phase space defined by pion transverse momentum \(p_{\rm T}>0.2\)~GeV/c and rapidity \(|y|< 2 \) is found to be \(20.5~\pm~0.3~(\rm {stat})~(\pm~3.1~\rm {syst})~\pm\)~0.8~(lumi)~\(\mu\)b. The differential cross sections for \(\pi^{+}\pi^{-}\) pairs as a function of the pion pair invariant mass, \(p_{\rm T}\), and \(y\), as well as a single-pion differential cross section as a function of pion \(p_{\rm T}\) are also measured and compared to several phenomenological predictions.
Photomultiplier tube (PMT) and Silicon Photo Multiplier (SiPM) are often used for detecting small number of photons or very weak radiations. A light guide usually connects these photodetectors to the ...test space. In this article, we investigate the effect of background signals caused by cosmic muons scintillation or interactions with PMT and SiPM, their light guide or input window materials. We study such interactions by making simulations using GATE software package and undertaking experiments using detector circuits developed as in~\cite{Raki:2022lwn}. The background cosmic muons can generate photons which will lead to errors in low radiation and single photon detection experiments especially if standard scintillators are not used. For such experiments, we conclude that the most useful method for cutting down the cosmic muons background should be by conducting the experiments deep underground or inside tunnels with several tens of meters of materials above it.
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