In this paper, we introduce a new method for solving variational inequality problems with monotone and Lipschitz-continuous mapping in Hilbert space. The iterative process is based on well-known ...projection method and the hybrid (or outer approximation) method. However we do not use an extrapolation step in the projection method. The absence of one projection in our method is explained by slightly different choice of sets in the hybrid method. We prove a strong convergence of the sequences generated by our method.
Search for heavy neutrino in K+→μ+νH decay Sadovsky, A. S.; Kurshetsov, V. F.; Filin, A. P. ...
The European physical journal. C, Particles and fields,
02/2018, Letnik:
78, Številka:
2
Journal Article
Recenzirano
Odprti dostop
A high statistics data sample of the
K
+
→
μ
+
ν
μ
decay was accumulated by the OKA experiment in 2012. The missing mass analysis was performed to search for the decay channel
K
+
→
μ
+
ν
H
with a ...hypothetic stable heavy neutrino in the final state. The obtained missing mass spectrum does not show peaks that could be attributed to existence of stable heavy neutrinos in the mass range
(
270
<
m
ν
H
<
375
)
MeV
/
c
2
. As a result, upper limits on the branching ratio and on the value of the mixing element
|
U
μ
H
|
2
are obtained.
Abstract A high statistics data sample of the $$K^{+}\rightarrow \mu ^{+}\nu _{\mu }$$ K+→μ+νμ decay was accumulated by the OKA experiment in 2012. The missing mass analysis was performed to search ...for the decay channel $$K^{+}\rightarrow \mu ^{+}\nu _{H}$$ K+→μ+νH with a hypothetic stable heavy neutrino in the final state. The obtained missing mass spectrum does not show peaks that could be attributed to existence of stable heavy neutrinos in the mass range $$(270< m_{\nu _{H}} < 375)$$ (270<mνH<375) MeV$$/c^{2}$$ /c2 . As a result, upper limits on the branching ratio and on the value of the mixing element $$|U_{\mu H}|^{2}$$ |UμH|2 are obtained.
First results on
-dependence measurements in inclusive
meson production in
interactions (
, Al, Cu, Sn, and W) are presented at
GeV/
c
. The ratios of the differential cross sections of four of these ...nuclei to the differential cross section on aluminum were measured and the dependence of these cross sections on the atomic of the nucleus was studied. The measurements were carried out in the kinematic region of the Feynman variable
and transverse momentum
GeV/
c
.
mesons were detected in the decay mode
at the SPASCHARM experimental setup using negative charged beams at beamline 14 of the U-70 accelerator complex.
Abstract A high statistics data sample of the decays of $$K^+$$ K+ mesons to three charged particles was accumulated by the OKA experiment in 2012 and 2013. This allowed to select a clean sample of ...about 450 events with $$K^{+}\rightarrow \pi ^{+}\pi ^{-}\pi ^{+}\gamma $$ K+→π+π-π+γ decays with the energy of the photon in the kaon rest frame greater than 30 MeV. The measured branching fraction of the $$K^{+}\rightarrow \pi ^{+}\pi ^{-}\pi ^{+}\gamma $$ K+→π+π-π+γ , with $$E_{\gamma }^{*} > 30\ \hbox {MeV}$$ Eγ∗>30MeV is equal to $$(0.71 \pm 0.05) \times 10^{-5}$$ (0.71±0.05)×10-5 . The measured differential branching fraction over photon energy is compared with the prediction of the chiral perturbation theory to $${\mathcal {O}}(p^{4})$$ O(p4) . A search for an up-down asymmetry of the photon with respect to the hadronic system decay plane is also performed.
Daily dynamics of greenhouse gas (GHG) emissions and cultivable bacterial populations have rarely been examined. The objectives were: (1) to investigate if dynamics of GHG emissions can be described ...by harmonics and are related to those of cultivable bacteria after soil disturbances in three grassland management systems; (2) to determine to which extent daily GHG emissions are related to environmental variables rather than disturbance events in two climate zones; and (3) to investigate differences in GHG emissions between organic and conventional tilled grassland versus no-till long-term grassland systems (OG, CG and LG, respectively). In replicated field experiments with OG, CG, and LG plots in the Netherlands and Russia, GHG (CO2, N2O and CH4) emissions and cultivable bacterial populations were measured daily during two one-month periods at each location. Tillage, fertilization, biomass incorporation and irrigation were considered disturbances. The dynamics were subjected to harmonics, cross-correlation, and canonical correspondence analyses (CCA). The dynamics of cultivable bacterial populations and GHG fluxes rarely reflected autonomous growth and death cycles of bacteria after a disturbance due to the overarching influences of environmental conditions, especially in spring. Thus, GHG emissions were influenced more by weather variables than by agronomic disturbances. This was confirmed by CCA. Cultivable bacterial populations were cross correlated with CO2 fluxes and sometimes N2O emissions, but generally not with CH4 fluxes. Average cultivable bacterial populations and CO2 emissions were highest in OG and lowest in LG; N2O emissions were mostly highest in CG and lowest in LG; and CH4 fluxes were frequently highest in OG and lowest in LG. Thus, although bacteria and GHG peaks were induced by disturbances, sometimes followed by autonomous oscillations due to growth and death cycles and associated cycles in nutrient and oxygen availability, the dynamics were mainly affected by environmental variables and long-term management, with the smallest GHG emissions from LG plots.
•Daily greenhouse gas (GHG) emissions were related to cultivable bacteria in grassland soils.•Despite irregular fluctuations, GHG oscillations occurred after some agronomic disturbances.•Cross correlations among CO2, N2O fluxes and cultivable bacteria suggested process sequences.•GHG emissions were influenced more by environmental variables than by agronomic disturbances.•GHG emissions mostly were high in organic, medium in conventional, and low in long-term plots.
Extracellular vesicles (EVs) produced by various cell types are heterogeneous in size and composition. Changes in the RNA sets of EVs in biological fluids are considered the basis for the development ...of new approaches to minimally invasive diagnostics and the therapy of human diseases. In this study, EVs were obtained from the blood of healthy donors by centrifugation, followed by ultracentrifugation. It was shown that EVs consist of several populations including small exosome-like vesicles and larger microvesicle-like particles. The composition of EVs' RNAs was determined. A549 lung adenocarcinoma cells were incubated with EV and the NGS analysis of differentially expressed genes was performed. During the incubation of A549 cells with EVs, the levels of mRNA encoding components for the NF-kB signaling pathway increased, as well as the expression of genes controlled by the NF-kB transcription factor. Overall, our results suggest that components of EVs trigger the NF-kB signaling cascade in A549 cells, leading to the transcription of genes including cytokines, adhesion molecules, cell cycle regulators, and cell survival factors. Our data provide insight into the interaction between blood EVs and human cells and can be used for designing new tools for the diagnosis and treatment of human diseases.
Superparamagnetic nanoparticles of zinc ferrite ZnFe2O4 were obtained by air heat treatment of iron and zinc sulfated layered double hydroxide (SLDH) Zn2Fe4(OH)12SO4·8H2O at 600°С for 1 h. The ...initial sulfated hydroxide was obtained on a silicon substrate as a result of 30 cycles of successive ionic layer deposition from 0.01 M solutions of the Mohr salt (NH4)2Fe(SO4)2 and zinc ammonia complex Zn(NH3)4(NO3)2. Iron and zinc SLDH nanocrystals have the nanosheets morphology with an average thickness of 3–7 nm and a diameter of about 17 nm which are oriented perpendicular to the silicon substrate plane. Physico-chemical processes which occur during thermal treatment (25–600°С) of iron and zinc sulfated layered double hydroxide and lead to the formation of zinc ferrite at 550°С are investigated by simultaneous thermal analysis. It was found that ZnFe2O4 nanocrystals with an average size of about 30 nm and isometric morphology, which partially preserve the morphological motifs of the original SLDH nanosheets, were formed as a result of the thermal treatment of sulfated hydroxide. The obtained ZnFe2O4 nanocrystals are chemically and phase-pure, have lattice parameters a = b = c = 8.4394 Å and behave like superparamagnetic nanoparticles: they are characterized by the magnetization of 1.85 (298 K) and 12.79 (77 K) emu/g with 18 kOe applied field, and the effective magnetic moment is μeff = 24.3 μB per formula unit. This phase-pure superparamagnetic ZnFe2O4 nanoparticles can be potentially used as the basis for magnetic fluids, gas sensors, drugs for hyperthermia and magnetic resonance imaging diagnostics.
Zinc-iron hydrosulfate (Zn2Fe4(OH)12SO4) nanocrystals with nanosheet morphology were synthesized via successive ionic layer deposition, and heat treatment in the air was used to obtain chemically and phase-pure superparamagnetic zinc ferrite (ZnFe2O4) nanoparticles with partial preservation of morphology. Display omitted
•2D nanocrystals of Zn2Fe4(OH)12SO4 were synthesized via successive ionic layer deposition from reaction solutions.•Heat treatment of Zn2Fe4(OH)12SO4 nanocrystals were used to obtain a chemical and phase-pure zinc ferrite ZnFe2O4 nanosheets.•It was shown that ZnFe2O4 nanosheets with spinel structure exhibit superparamagnetic behavior in a wide temperature range.
The present study is focused on the problem of reconstruction of the magnetic configuration in the magnetic reconnection electron diffusion region (EDR). The problem is addressed in the frame of ...electron magnetohydrodynamics with kept electron inertia term. We introduce the new reconstruction model independent of divergence of the electron pressure tensor and reconnection electric field. The model is tested on the magnetotail reconnection event of July 11, 2017 observed by the Magnetospheric Multiscale (MMS) spacecraft in the course of crossing the very core part of the reconnection region, the internal EDR. This new model demonstrates considerably better accuracy of the longitudinal electron velocity reconstruction due to the lower sensitivity to the configuration deviation from the two‐dimensional time‐independent model adopted in our study. We suggest also a new technique to estimate the guide field, implementing the reconstruction of magnetic potential of the in‐plane magnetic field and relying on symmetric properties of magnetic reconnection.
Plain Language Summary
Magnetic reconnection is a fundamental plasma process responsible for the magnetic field reconfiguration and transforming magnetic energy to kinetic and thermal energy of plasma. In the Earth's magnetosphere, the magnetospheric conditions are monitored by several spacecraft missions. Among them, the NASA Magnetospheric Multiscale (MMS) mission is designed for exploring the process of reconnection. On July 11, 2017 at about 22:34 UT MMS was located in the magnetotail at a very fortunate position, intersecting the reconnection region in its very central part, the so‐called electron diffusion region (EDR).
Since MMS consists of four identical spacecraft, MMS provides an excellent tool for testing analytical models of reconnection. Taking the data of one probe as the boundary condition for the analytical model, one can compare the results of calculations with other probes data. In the present paper we suggest a new model of EDR, and compare it to the existing one using the data of 2017/07/11 event. This comparison has shown that the electron inertia term plays an important role in the EDR physics; the proper handling of this term allows considerable improvement of the EDR reconstruction accuracy.
Key Points
A model for electron diffusion region (EDR) reconstruction in electron magnetohydrodynamics (EMHD) approximation with kept electron inertia is developed
Reconstruction of the out‐of‐plane magnetic field is performed independent of the reconnection electric field and pressure anisotropy
Reconstruction is applied for self‐consistent estimate of the guide field value and local coordinate system orientation
The temperature behavior of bismuth orthoferrite nanoparticles obtained by the glycine-nitrate combustion method was studied by high-temperature X-ray diffractometry and complex thermal analysis. The ...region of stability of the material in a single-phase state was found. It was shown that the nanocrystalline BiFeO
3
did not undergo decay in the temperature interval 550–780 °С. In this temperature interval, we have obtained the nanocrystalline material with average crystallite sizes 40–90 nm and average particle sizes 100–150 nm the sizes of which depend on temperature. The features of formation of BiFeO
3
and the process of their sintering were studied. Results show that the crystallite growth slowed down after the amorphous phase disappeared. The sintering of nanopowder became more intense in the temperature interval 600–700 °С, but no noticeable increase in the crystallite sizes occurred. The magnetic behavior of obtained material was also discussed. It was found to be consistent with the concept of violation of the cycloidal magnetic order in bismuth orthoferrite.
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