Total Capture Rate of Negative Muons in 24Mg Belov, V. V.; Gusev, K. N.; Zhitnikov, I. V. ...
Physics of particles and nuclei letters,
2022/6, Letnik:
19, Številka:
3
Journal Article
Recenzirano
A description of an experiment devoted to determining the total capture rates of negative muons in
24
Mg is presented. The investigations are carried out using a low-energy muon beam with high ...intensity (10
4
s
–1
) at the SμS meson facility in Villigen, Switzerland, with the help of the mini-Ball cluster of HPGe detectors. The experimental approach based on our previous works is described. The justification of the difference between these methods and those used in previous investigations is presented. It is pointed out that our method is potentially much more precise and does not depend on the muon absorption in the surrounding matter. A comparison of these results with those of previous experiments and theoretical calculations is also presented.
The NEMO-3 detector has been taking data in the Fréjus underground laboratory (LSM, France) since February 2003 and is devoted to the search for neutrinoless double-beta decay (0νββ). After 389 ...effective days of data collection from February 2003 until September 2004 (Phase I), no evidence for neutrinoless double-beta decay was found from ∼7 kg of 100Mo and ∼1 kg of 82Se. The corresponding limits for the half-lives are T1/2(0νββ) > 4.6 × 1023 yr for 100Mo and T1/2(0νββ) > 1.0 × 1023 yr for 82Se (90% C.L.). They lead to the following limits for the effective Majorana neutrino mass: 〈mν〉 < 0.7–2.8 eV for 100Mo and 〈mν〉 < 1.8–4.9 eV for 82Se. The half-lives of the two-neutrino double-beta decay (2νββ) have been measured for 100Mo, 82Se, 116Cd, 150Nd, and 96Zr and reported here as well.
Searching for the β+EC and EC/EC Decays of 74Se Rukhadze, N. I.; Barabash, A. S.; Brudanin, V. B. ...
Bulletin of the Russian Academy of Sciences. Physics,
08/2020, Letnik:
84, Številka:
8
Journal Article
Recenzirano
Double beta decay (β
+
EC, EC/EC) of
74
Se was investigated at the Modane underground laboratory (LSM, France; 4800 m of water equivalent) using the OBELIX ultralow-background HPGe detector with a ...sensitive volume of 600 cm
3
and a sample of natural selenium with a mass of 1.6 kg containing ~0.89% (~14.24 g) of
74
Se. The new experimental limits for β
+
EC and EC/EC decays of
74
Se to ground 0
+
and excited
596 keV, and
1204 keV states of
74
Ge, were obtained from experimental data accumulated over 135 days.
A new experiment devoted to searches for double electron capture in sup.106Cd decay is being performed at the Modane underground laboratory (4800 mwe) with the 32-detector TGV-2 spectrometer. The ...limit T.sub.1/2 (2υEC/EC) > 2.0 x 10.sup.20 yr at a 90% confidence level (C.L.) was obtained from a preliminary analysis of data obtained over 2250 h of measurements with about 23.2 g sample enriched in the isotope sup.106Cd to 99.57%. The limits T.sub.1/2(KL 2741 keV) > 0.9 x 10.sup.20 yr and T.sub.1/2(KK 2718 keV) >> 1.4 x 10.sup.20yr at a 90% C.L. on the neutrinoless decay of sup.106Cd were obtained from measurements performed with the Obelix low-background spectrometer from high-purity germanium (HPGe spectrometer) for a sample of mass about 23.2 g enriched in the isotope sup.106Cd. DOI: 10.1134/S1063778815060058
Aims:
adaptation and validation of the ELISA method insulin glargine determination for the pharmacokinetic study, practical approval in the biosimilars clinical trial.
Materials and methods.
Serum ...insulin glargine determination was measured using a commercial ELISA kit. All tests were run on a Personal LAB machine (Adaltis S.r.l., Rome, Italy) with test systems for measuring the concentration of insulin glargine (Invitron Ltd., United Kingdom); human insulin concentrations were measured in the samples from the study for correction of cross-reactivity. Clinical part of this study included 42 male patients aged 18–65 with diabetes mellitus type 1. This was a double-blind, randomized, crossover clamp study with wash-out period of 7–14 days. Comparisons drugs: Insulin Glargine (glargine) solution for subcutaneous administration, 100 U/ml (GEROPHARM, Russia) and Lantus® (glargine) solution for subcutaneous administration, 100 U/ml (Sanofi-Aventis Deutschland GmbH, Germany).
Results.
At the stage of the method adaptation the modification of original manufacturer’s method was performed; the full validation of modified analytical method for all parameters (selectivity, specificity, precision of calibration curves, intra- and inter-batch precision and accuracy, carry-over, dilution integrity, stability of solutions, stability in biologic matrix, parallelism) in accordance with regulatory authorities requirements has been done. The primary endpoint for long-acting insulins – AUCins.0-τ was calculated. Insulin Glargine and Lantus® are equivalent based on AUCins.0-τ data (point estimation for ratio of geometric means was 99 %, the confidence intervals for the ratio of the geometric mean for AUCins.0-τ was 81.02–120.62 %, that correspond to acceptance range 80.00–125.00 %).
The next generation of very-short-baseline reactor experiments will require compact detectors operating at surface level and close to a nuclear reactor. This paper presents a new detector concept ...based on a composite solid scintillator technology. The detector target uses cubes of polyvinyltoluene interleaved with 6LiF:ZnS(Ag) phosphor screens to detect the products of the inverse beta decay reaction. A multi-tonne detector system built from these individual cells can provide precise localisation of scintillation signals, making efficient use of the detector volume. Monte Carlo simulations indicate that a neutron capture efficiency of over 70 % is achievable with a sufficient number of 6LiF:ZnS(Ag) screens per cube and that an appropriate segmentation enables a measurement of the positron energy which is not limited by γ-ray leakage. First measurements of a single cell indicate that a very good neutron-gamma discrimination and high neutron detection efficiency can be obtained with adequate triggering techniques. The light yield from positron signals has been measured, showing that an energy resolution of 14%/√E(MeV) is achievable with high uniformity. A preliminary neutrino signal analysis has been developed, using selection criteria for pulse shape, energy, time structure and energy spatial distribution and showing that an antineutrino efficiency of 40% can be achieved. It also shows that the fine segmentation of the detector can be used to significantly decrease both correlated and accidental backgrounds.
Detection of antineutrino by the reaction of the inverse
β
-decay can be used for an independent monitoring of a nuclear reactor power. DANSS detector is located directly under a commercial WWER-1000 ...reactor and counts up to 5000 antineutrino per day, providing the accuracy of 1.5% in 2 days of the flux measurement. A powerful system of the passive and active shielding in combination with the fine spatial segmentation of the detector allows to diminish the contribution of the background processes to a level, negligible in comparison to the statistical error. The influence of the nuclear fuel composition on the neutrino flux can be accounted for based on the input from the NPP staff.
The approaches to bioanalytical method development for determination of substances which contain unstable functional groups in the structure are described. The oxidation and the hydrolysis are main ...causes of the decomposition of substances in biological fluids. Phenolic hydroxyls contain drugs were selected as examples of oxidable compounds, glucuronides of drugs were selected as examples of hydrolysable compounds. Determination of mycophenolic acid, which contains one phenolic hydroxyl and metabolized by formation of glucuronides, in plasma was performed using high performance liquid chromatography with mass-spectrometry and tandem mass-spectrometry detection. Methyldopa, which contains two phenolic hydroxyls, in stabilized plasma was assayed by high performance liquid chromatography – tandem mass-spectrometry in the range of 0.02–3.00 μg/ml. Concentrations of desmethyl mebeverine acid, which contains in the structure one phenolic hydroxyl and metabolized by formation of phenolic glucuronide, was measured simultaneously with mebeverine acid in the range of 10–2000 ng/ml. The influence of the ion source conversion of glucuronides on the quantitative determination of the substances was studied in the initial part of methods development. The next, selection of anticoagulants based on the study of short-term stability and freeze/thaw stability of the analytes and back conversion of their glucuronides was performed. The combination of anticoagulant K3EDTA and the antioxidant solution containing a mixture of ascorbic acid, sodium sulfite and sodium hydrogen carbonate in the concentrations of 5.0 %, 0.2 % and 2.4 %, respectively, was used to prevent degradation of methyldopa.
Abstract
This work is devoted to the study of tribotechanical properties of 3D printed samples from ABS plastic. The results of determining the coefficient of friction and mass wear of the samples ...obtained by 3D-printing with different printing heights during the friction testing on machine II 5018 are presented. It is shown that in order to reduce the coefficient of friction and mass wear of the ABS plastic specimen, it is recommended to produce specimens with a higher print height. 3D printed parts with 0.3 mm layer height have shown the best results because of greater layer adhesion.
Introduction
. Computed tomography angiography (CTA) is widely used to detect atherosclerotic changes in coronary arteries (CA). However, the method is limited by the impossibility to perform ...functional assessment of detected stenoses. Perfusion computed tomography of the myocardium (PCT) can be used for this purpose.
Aim of the study
. To assess diagnostic accuracy of PCT of the myocardium with transesophageal electrocardiostimulation (TEES) and stress-echocardiography (stress-echoCG) with veloergometry (VEM) in detection of transient ischemia in patients with initial diagnosis of “acute coronary syndrome” (ACS) with borderline stenoses (50–75%) in CA in relation to measurements of fractional flow reserve (FFR).
Materials and Methods
. The study included 30 patients with the initial diagnosis of ACS with borderline (50–75%) stenoses in CA according to CTA or coronary angiography (CAG). Subsequently, they underwent myocardial PCT with 320-row detector with TEES, as well as stress-echoCG with VEM. Invasive FFR measurement was used as a reference method. FFR value < 0.8 indicated hemodynamic significance of stenosis. Myocardial perfusion was assessed visually. Regional myocardial contractility of the left ventricle was assessed by stress-echoCG.
Results
. All patients were examined according to the stated protocol. PCT with TEES revealed FFR-significant stenoses with sensitivity, specificity, prognostic value of positive result and prognostic value of negative result 56, 93, 90, 65% respectively, stress-echoCG with VEM 62, 93, 91, 68% respectively.
Conclusion
. Myocardial PCT with TEES enables to detect perfusion defects associated with transient ischemia, and the diagnostic accuracy of the method in comparison with FFR is comparable with the already well-proven stress-echoCG. The use of PCT with TEES in combination with CTA can be considered as a promising diagnostic tool in patients without known coronary anatomy and with suspected ACS.
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