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Abstract The $$K^{+} \rightarrow \pi ^{+}\pi ^{0}\pi ^{0}\gamma $$ K + → π + π 0 π 0 γ decay is observed by the OKA collaboration. About 60 events of the decay observed with signal:noise $$\approx 1$$ ≈ 1 . The branching ratio obtained by normalization to $$K^{+} \rightarrow \pi ^{+}\pi ^{0}\pi ^{0}$$ K + → π + π 0 π 0 is measured to be $$(3.7 \pm 0.9(stat) \pm 0.3(syst))\times 10^{-6}$$ ( 3.7 ± 0.9 ( s t a t ) ± 0.3 ( s y s t ) ) × 10 - 6 for $$E_{\gamma }^*>10\,\textrm{MeV}$$ E γ ∗ > 10 MeV . The branching ratio, $$\gamma $$ γ energy spectrum and angular distribution are consistent with ChPT prediction.

Abstract A high-statistics data sample of the $$K^{+}$$ K + decays is recorded by the OKA collaboration. A missing mass analysis is performed to search for a light invisible pseudoscalar axion-like particle (ALP) a in the decay $$K^{+} \rightarrow \pi ^{+} \pi ^{0} a$$ K + → π + π 0 a . No signal is observed, and the upper limits for the branching ratio of the decay are calculated. The $$90\%$$ 90 % confidence level upper limit changes from $$2.5\cdot 10^{-6}$$ 2.5 · 10 - 6 to $$2\cdot 10^{-7}$$ 2 · 10 - 7 for the ALP mass from 0 to 200 MeV/ $$c^{2}$$ c 2 , except for the region of $$\pi ^{0}$$ π 0 mass, where the upper limit is $$4.4\cdot 10^{-6}$$ 4.4 · 10 - 6 .

Abstract Results of a study of the $$K^+ \rightarrow \pi ^{0} e^{+} \nu \gamma $$ K + → π 0 e + ν γ decay at OKA setup are presented. More than 32,000 events of this decay are observed. The differential spectra over the photon energy and the photon–electron opening angle in kaon rest frame are presented. The branching ratios, normalized to that of $$K_{e3}$$ K e 3 decay are calculated for different cuts on $$E^*_\gamma $$ E γ ∗ and $$cos\Theta ^{*}_{e\gamma }$$ c o s Θ e γ ∗ . In particular, the branching ratio for $$E^{*}_{\gamma }>30$$ E γ ∗ > 30 MeV and $$\Theta ^{*}_{e \gamma }>20^{\circ }$$ Θ e γ ∗ > 20 ∘ is measured R = $$\frac{Br(K^+ \rightarrow \pi ^{0} e^{+} \nu _{e} \gamma ) }{Br(K^+ \rightarrow \pi ^{0} e^{+} \nu _{e})} $$ B r ( K + → π 0 e + ν e γ ) B r ( K + → π 0 e + ν e ) = = (0.587±0.010(stat.)±0.015(syst.)) $$\times 10^{-2}$$ × 10 - 2 , which is in a good agreement with ChPT $$O(p^{4})$$ O ( p 4 ) calculations.

A precise understanding of the influence of a quantum system's environment on its dynamics, which is at the heart of the theory of open quantum systems, is crucial for further progress in the development of controllable large-scale quantum systems. However, existing approaches to account for complex system-environment interaction in the presence of memory effects are either based on heuristic and oversimplified principles or give rise to computational difficulties. In practice, one can leverage on available experimental data and replace first-principles simulations with a data-driven analysis that is often much simpler. Inspired by recent advances in data analysis and machine learning, we propose a data-driven approach to the analysis of the non-Markovian dynamics of open quantum systems. Our method allows, on the one hand, capturing the most important characteristics of open quantum systems such as the effective dimension of the environment and the spectrum of the joint system-environment quantum dynamics, and, on the other hand, reconstructing a predictive model of non-Markovian quantum dynamics, and denoising the measured quantum trajectories. We demonstrate the performance of the proposed approach with various models of open quantum systems, including a qubit coupled with a finite environment, a spin-boson model, and the damped Jaynes-Cummings model.

Abstract A precise measurement of the vector and axial-vector form factors difference $$F_V-F_A$$ FV-FA in the $$K^+\rightarrow {\mu ^+}{\nu _{\mu }}{\gamma }$$ K+→μ+νμγ decay is presented. About 95K events of $$K^+\rightarrow {\mu ^+}{\nu _{\mu }}{\gamma }$$ K+→μ+νμγ are selected in the OKA experiment. The result is $$F_V-F_A=0.134\pm 0.021(stat)\pm 0.027(syst)$$ FV-FA=0.134±0.021(stat)±0.027(syst) . Both errors are smaller than in the previous $$F_V-F_A$$ FV-FA measurements.

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.

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

This study explores the combined toxic effect of Mn(II) and resorcinol (0.01 n and 0.2 n) on duckweed (Lemna minor). During the acute experiments, the plants released electrolytes into the aquatic environment after 30 min of exposure to the toxicants, indicating a disruption of tissue permeability as a test response. The experiments showed that the toxicity of the equinormal mixtures of resorcinol and Mn(II) (0.2 n each) increased relative to their single solutions. This was observed both in the freshly prepared solutions and in the solutions stored for 20 h prior to the experiments. The change in the UV absorption spectra indicates that there was complexation or other interaction between resorcinol and Mn(II) at equinormal concentrations (0.01 n). At the Mn(II) : resorcinol ratio of 1:20 (0.01 n Mn(II) and 0.2 n resorcinol), the toxicity of the system to duckweed decreased compared to the separate effects of these substances. The results obtained highlight the importance of considering the interactions between heavy metals and phenolic compounds when assessing the quality of aquatic environments.

The article is a research into psychological and pedagogic support of sportsmen aged 18–25 years old, with taking into account the gender factor, at the stages of training with the strength exercises. It states methods of psychical reserves mobilization of different psychophysical types of sportsmen, aimed at training process efficiency increase in order to reach high results during competitions.Introduction. The article is based at the methodic of classical development of sportsmen’s strength abilities in powerlifting in composition with psychological methods of psychological and pedagogic support (PPS) for increasing of reliability and successfulness of pre-competition training. PPS is considered to be a combination of targets, media, methods and circumstances of planning, realization and control of the process of formation, activation and optimization of sportsmen’s psychological processes, at the stages of preparing for competitions and participating in them. Research target. Theoretical elaboration and experimental substantiation of the methodic of PPS training preparation for the competitions when going in for powerlifting and weightlifting.Materials and methods. The method of control test, pedagogic experiment (PE), fitness tests, anthropometrical methods, psychological development of personality methods, mathematical statistics methods. The research was being performed during five weeks (2020-02-01–2020-03-15). During the pedagogical experiment (PE), strength trainings were based at five-week cycle by B.I. Sheyko, which is equal to one pre-competition mesocycle. Sportsmen aged 18–25 years old formed two groups of 20 persons each: control group (CG) and experimental group (EG), divided [inside] by the gender factor. CG and EG were training with the classical powerlifting methodic, in EG it was supplemented with psychological processes optimization methods.The methodic of PPS preparation for a competition included: learning of goal-setting, forming of readiness for competitions, learning of coping, activation of motivation processes, increase of self-control and of psychoregulation of behavior and sport activity.Results. The authors elaborated five-week mesocycle (medium cycle) of training for powerlifters aged 18-25 years old. The forming impact of the complex of PPS methods in EG caused certain growth of strength results in EG at the end of PE: each of CG sportswomen lifted 142.5 kg in the sum of three-lift, CG sportsmen — 215 kg. In EG the result of sportswomen is 190 kg, the result of sportsmen is 250 kg. The growth, when comparing EG and CG, was 57.5 kg for sportswomen and 35 kg for sportsmen in favour of RG with PPS. Psychophysical types of young powerlifters, who need psychological and pedagogic support, were identified, recovery measures for psychological preparation were proposed.Conclusion. PPS in the complex with strength trainings caused certain growth of strength indexes of powerlifters aged 18–25 years old, with taking into account the gender factor. Strength indexes of girls progressed 1,8–2 times more significantly, than of men. When performing PPS, they wust take into account the gender specifics of powerlifters, attached to different impact of psychological preparation methods on boys and girls.

Purpose: physiological substantiation of the physical activity selection based on the differences in the functional state of schoolchildren with different types of cardiovascular system autonomic regulation.Methods: 60 schoolchildren, 12 years old, were examined. The experimental group consisted of schoolchildren who were engaged in physical exercises for 6 months according to the developed individual typological program. Students in the control group followed the school programm. The assessment of the functional state was carried out by the method of “Express assessment of the physical health of schoolchildren” and the method of diagnosing indicators of heart rate variability.Results: at the beginning of the survey, the indicators in the experimental group and the control group were determined by the characteristics of 4 types of autonomic regulation: I, II, III, IV. Of these, I, II corresponded to the predominance of sympathetic-tonic destabilizing influences on the cardiovascular system, in IV parasympathetic influences prevailed, manifested in the asthenia of the functional state of students. Whereas type III refers to the physiological norm and manifested itself in the form of a balance of regulatory influences of the parts of the autonomic nervous system.Conclusions: at the control examination, the indicators of adaptation and health improved in all types of schoolchildren, while in the control group there was no positive dynamics of indicators of adaptation and health. This testifies to the effectiveness of individually typologically oriented classes at a physical education lesson as having a health-improving effect on schoolchildren.

The influence of storage of actinobacteria Streptomyces hygroscopicus RIA 1433T, Nonomuraea roseoviolacea subsp. carminata INA 4281 and Nonomuraea sp. INA 34-06 at extremely low temperatures (-70°С) for 1.5 years was studied with respect to their viability and antibiotic activity. The spores of the actinobacteria preserved their high viability when freezed at a concentration of 105-107 CFU/ml. As for the antibiotic activity against the test culture Micrococcus luteus ATCC 9341, the strains differed: the S.hygroscopicus RIA 1433T colonies preserved their antibiotic activity against the test culture, the antibiotic activity of Nonomuraea roseoviolacea subsp. carminata lowered by 5% and that of N. sp. INA 34-06 lowered by 44%. Differences in the resistance of the strains to the storage at the extremely low temperatures were observed when the suspensions contained low concentrations of the spores (102 CFU/ml): S.hygroscopicus RIA 1433T preserved its viability and antibiotic activity during 1.5 years, while N.roseoviolacea subsp. carminata INA 4281 and N. sp. INA 34-06 lost the viability by the 8th month of the storage. The study showed that 10% glycerol solution used as a cryoprotector during the storage had no effect on viability and antibiotic activity of the actinobacteria.

Absolutely separable states ϱ remain separable under arbitrary unitary transformations . By example of a three qubit system we show that in a multipartite scenario neither full separability implies bipartite absolute separability nor the reverse statement holds. The main goal of the paper is to analyze quantum maps resulting in absolutely separable output states. Such absolutely separating maps affect the states in a way, when no Hamiltonian dynamics can make them entangled afterwards. We study the general properties of absolutely separating maps and channels with respect to bipartitions and multipartitions and show that absolutely separating maps are not necessarily entanglement breaking. We examine the stability of absolutely separating maps under a tensor product and show that is absolutely separating for any N if and only if Φ is the tracing map. Particular results are obtained for families of local unital multiqubit channels, global generalized Pauli channels, and combination of identity, transposition, and tracing maps acting on states of arbitrary dimension. We also study the interplay between local and global noise components in absolutely separating bipartite depolarizing maps and discuss the input states with high resistance to absolute separability. [ABSTRACT FROM AUTHOR]