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The T2K experiment presents new measurements of neutrino oscillation parameters using 19.7 (16.3) × 10 20 protons on target (POT) in (anti-)neutrino mode at the far detector (FD). Compared to the previous analysis, an additional 4.7 × 10 20 POT neutrino data was collected at the FD. Significant improvements were made to the analysis methodology, with the near-detector analysis introducing new selections and using more than double the data. Additionally, this is the first T2K oscillation analysis to use NA61/SHINE data on a replica of the T2K target to tune the neutrino flux model, and the neutrino interaction model was improved to include new nuclear effects and calculations. Frequentist and Bayesian analyses are presented, including results on sin 2 θ 13 and the impact of priors on the δ CP measurement. Both analyses prefer the normal mass ordering and upper octant of sin 2 θ 23 with a nearly maximally CP-violating phase. Assuming the normal ordering and using the constraint on sin 2 θ 13 from reactors, sin 2 θ 23 = 0. 561 - 0.032 + 0.021 using Feldman–Cousins corrected intervals, and Δ m 32 2 = 2. 494 - 0.058 + 0.041 × 10 - 3 eV 2 using constant Δ χ 2 intervals. The CP-violating phase is constrained to δ CP = - 1. 97 - 0.70 + 0.97 using Feldman–Cousins corrected intervals, and δ CP = 0 , π is excluded at more than 90% confidence level. A Jarlskog invariant of zero is excluded at more than 2 σ credible level using a flat prior in δ CP , and just below 2 σ using a flat prior in sin δ CP. When the external constraint on sin 2 θ 13 is removed, sin 2 θ 13 = 28. 0 - 6.5 + 2.8 × 10 - 3 , in agreement with measurements from reactor experiments. These results are consistent with previous T2K analyses. [ABSTRACT FROM AUTHOR]

In this paper we study the influence of nuclear medium effects on quasi-elastic neutrino–nucleus scattering processes. We focus on effects provided by the nuclear mean field and random phase correlations and pay special attention to differences between neutrino- and antineutrino-induced reactions. We confront our results with the T2K and MiniBooNE data for both neutrinos and antineutrinos and the neutrino–antineutrino asymmetry. In view of the recently published ab initio results we provide a careful comparison between our cross section predictions and the ab-initio calculations. [ABSTRACT FROM AUTHOR]

The mechanism of anomalous resistivity is still an open and unsolved problem in collisionless magnetic reconnection. Studies show that magnetic reconnection regions often have magnetic island-chain structures. By using the test particle simulation, the chaos-induced resistivity is calculated in the regions around X points and O points, respectively. The results show that the chaos-induced resistivity in the X-type region is higher than that in the O-type region by an order of magnitude for the case with a strong guide field or a high magnetic island parameter. For the case of a weak guide field, however, the chaos-induced resistivity in the X-type region sensitively depends on the guide field and may be close to or less than that in the O-type region in the case of a low magnetic island parameter. This work will be helpful for us to understand the magnetic energy dissipation of occurring in collisionless reconnection regions as well as the dynamical evolution of reconnection current sheets. [ABSTRACT FROM AUTHOR]

This paper reports on the electrochemical behavior of an ATP biosensor that utilizes glucose oxidase (GOx) and hexokinase (Hex) immobilized within the electroactive polymer, polyethylenedioxythiophene (PEDOT). This biosensor design detects ATP indirectly at 0.85 V vs. Ag/AgCl based on the oxidation current for enzymatically generated H2O2, and at −0.20 V; a potential at which improved analyte selectivity is achieved. The detection figures of merit at both detection potentials are a response time of 15±1 s, an experimental detection limit of 10.0±0.2 μmol L−1 (S/N=3), and a sensitivity in the range of 100–500 mA M−1cm−2. [ABSTRACT FROM AUTHOR]

The charge-conjugation and parity-reversal (CP) symmetry of fundamental particles is a symmetry between matter and antimatter. Violation of this CP symmetry was first observed in 19641, and CP violation in the weak interactions of quarks was soon established2. Sakharov proposed3 that CP violation is necessary to explain the observed imbalance of matter and antimatter abundance in the Universe. However, CP violation in quarks is too small to support this explanation. So far, CP violation has not been observed in non-quark elementary particle systems. It has been shown that CP violation in leptons could generate the matter–antimatter disparity through a process called leptogenesis4. Leptonic mixing, which appears in the standard model's charged current interactions5,6, provides a potential source of CP violation through a complex phase δCP, which is required by some theoretical models of leptogenesis7–9. This CP violation can be measured in muon neutrino to electron neutrino oscillations and the corresponding antineutrino oscillations, which are experimentally accessible using accelerator-produced beams as established by the Tokai-to-Kamioka (T2K) and NOvA experiments10,11. Until now, the value of δCP has not been substantially constrained by neutrino oscillation experiments. Here we report a measurement using long-baseline neutrino and antineutrino oscillations observed by the T2K experiment that shows a large increase in the neutrino oscillation probability, excluding values of δCP that result in a large increase in the observed antineutrino oscillation probability at three standard deviations (3σ). The 3σ confidence interval for δCP, which is cyclic and repeats every 2π, is [−3.41, −0.03] for the so-called normal mass ordering and [−2.54, −0.32] for the inverted mass ordering. Our results indicate CP violation in leptons and our method enables sensitive searches for matter–antimatter asymmetry in neutrino oscillations using accelerator-produced neutrino beams. Future measurements with larger datasets will test whether leptonic CP violation is larger than the CP violation in quarks. The T2K experiment constrains CP symmetry in neutrino oscillations, excluding 46% of possible values of the CP violating parameter at a significance of three standard deviations; this is an important milestone to test CP symmetry conservation in leptons and whether the Universe's matter–antimatter imbalance originates from leptons. [ABSTRACT FROM AUTHOR]

A strain sensor using a stress-magnetoresistance effect of a Ni-Fe/Mn-Ir exchange-coupled magnetic film was fabricated and evaluated. The stress magnetoresistance is used in the inverse magnetostrictive effect and the magnetoresistance effect in the magnetic film since an external stress is changed into an electric resistance in it. A compressive stress was measured by the strain sensor with a Mn-Ir (10 nm)/Ni-Fe (50 nm)/Ru (1 nm) exchange-coupled film. The change in resistivity ▵p/p is proportional to the applied compressive stress σ for σ⩽50 MPa in the strain sensor. When increasing Ni-Fe layer thickness in the strain sensor, a gauge factor increased. [ABSTRACT FROM AUTHOR]

We present a model to investigate the lateral transport and anisotropic magnetoresistance (AMR) of a permalloy film, with a two-dimensional array of unfilled holes (antidotes). The current density distribution j is first obtained numerically by solving the Poisson equation in the absence of B field, while the magnetization M of the film is calculated via micromagnetics. The M and j distributions are linearly interpolated through the sample, and then combined in a self-consistent scheme to obtain the galvanomagnetic effects (normal and planar Hall effects), which affect the current direction. The overall AMR is evaluated from the parallel contributions of the resulting current paths. Modifying the film geometry by reducing the antidot spacing results in an increase in the peak AMR ratio, which may be explained by the inhomogeneous current density and magnetization alignment induced by the antidots. [ABSTRACT FROM AUTHOR]

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Features the magneto-optical properties of ion-implanted iron (Fe) films along with structural changes of Fe films induced by terbium-, bismuth-, and Fe-ion implantations. Polar Kerr rotation in a static magnetic field; Faraday rotation in a pulse magnetic field; Enhancement of the Faraday rotation in the ion implanted Fe layer.

Regular square FeSexnanoflakes with tetragonal PbO-type phase and selenium deficiency have been grown from an inorganic iron source, i.e.ferrous chloride and selenium trioctylphosphine through a simple solution-based route in the co-solvent of oleylamine and oleic acid. The phase and structure are identified by powder X-ray diffraction and electron microscopy. The square nanoflakes are revealed to be bound by two larger {001} planes and four equivalent smaller {100} side surfaces. The appearance of the larger {001} planes and flaky morphology inherently results from the greatest atom density on {001} lattice planes and the largest d001spacing. The addition of the organic acid, i.e.oleic acid, at a proper stage during heating of the starting materials, is of great importance to the yield of the tetragonal PbO-type phase. Interestingly, the chemical composition and the edge length of the single crystalline FeSexnanoflakes can be tailored readily by using an organic diol which is suggested to serve as a reducing agent and chemical ligand. Thus, the deficiency of selenium can be highly reduced and the top-bottom surface area be enlarged. [ABSTRACT FROM AUTHOR]

The aim of the study was to give an overview of the mechanism of inhibition of Na+/K+-ATPase activity induced by some specific and non specific inhibitors. For this purpose, the effects of some ouabain like compounds (digoxin, gitoxin), noble metals complexes ([PtCl2DMSO2], [AuCl4]−, [PdCl4]2−, [PdCl(dien)]+, [PdCl(Me4dien)]+), transition metal ions (Cu2+, Zn2+, Fe2+, Co2+), and heavy metal ions (Hg2+, Pb2+, Cd2+) on the activity of Na+/K+-ATPase from rat synaptic plasma membranes (SPM), porcine cerebral cortex and human erythrocytes were discussed. [ABSTRACT FROM AUTHOR]

FeSe films have been grown on GaAs (001) substrates by low-pressure metal organic vapor deposition at different temperatures. X-ray diffraction analysis indicated that the FeSe films grown at substrate temperatures (Ts) between 220 and 340 °C were preferentially oriented with tetragonal structure. It was not possible to deposit films at Ts above 400 °C. The atomic molar ratios of Se/Fe increased with increasing the flow rate of H2Se/Fe(CO)5 and the growth temperature. The electronic property results showed that the conductive type of FeSe could be adjusted by controlling the growth temperature. The coercivity of FeSe decreased with increasing the growth temperature from 220 to 300 °C due to the improvement of crystal quality. [ABSTRACT FROM AUTHOR]

Frost-damaged or prematurely harvested canola seed (rapeseed) may yield oil with a high chlorophyll content (50-60 µg/ml). Enzymatic hydrolysis of chlorophyll, added to buffer/surfactant, buffer/acetone or buffer/acetone/canola oil, to produce water-soluble chlorophyllide (green pigment) was studied using a crude chlorophyllase preparation (acetone-dried chloroplasts) from 15 to 20-day-old sugar beet seedlings. In buffer/surfactant, the optimum pH for enzyme activity was temperature dependent. At 30 C and 0.24% Triton X-100 (or 30% acetone), chlorophyllase showed maximum activity toward a crude chlorophyll preparation over the range of pH 8-10. At 60 C, the activity was more than twofold higher, with a sharp maximum at ∼pH 8. Mg enhanced the activity with an optimal concentration of 50 mM. At pH 7.5, 50 C and in the presence of only 6% acetone, the enzyme showed high affinity for chlorophyll (Km=15µM or 13.5 µg/ml), suggesting that the natural chlorophyll concentrations found in green canola oils might facilitate high enzymatic efficiencies. The crude enzyme was stable in buffer/acetone at pH 7.5 and 50 C for at least two hr. With acetone concentrations as low as 6%, maximum enzyme activities in buffer and buffer/canola oil required intensive mixing (homogenization) of the various substrate, enzyme and liquid phases. In general, the rate and extent of chlorophyll hydrolysis were greater in buffer than in buffer/oil. In both reaction systems, chlorophyll hydrolysis slowed down with time due to accumulation of phytol, which proved to be a competitive inhibitor (K=11 µM or 3.3 µg/ml). The other hydrolysis product, chlorophyllide, did not affect enzymatic activity. Crude canola oil used in the reconstitution of green oil did not support enzymatic chlorophyll hydrolysis without prior degumming and desoaping. The optimum buffer/oil ratio of the reaction mixtures was above 2/1 (v/v). [ABSTRACT FROM AUTHOR]

The present state of the theory of hydrogen embrittlement of metals is analyzed and the shortcoming of several vanants of this theory are discussed. A new hypothesis of hydrogen embrittlement is presented; the hypothesis is based on concepts of dynamic strain aging and makes it possible to overcome certain difficulties of the theory of this phenomenon. [ABSTRACT FROM AUTHOR]

FeSe film was prepared on GaAs (001) substrate by low pressure metal-organic chemical vapor deposition. The x-ray diffraction measurement indicated that the sample was preferentially oriented with tetragonal structure. The structure relationship between FeSe epilayer and GaAs (001) substrate has been studied. The critical behavior in the temperature-dependent resistivity at ∼290 K is close to the Curie temperature, which confirmed that the transformation from ferromagnetism to paramagnetism could be responsible for the critical behavior. [ABSTRACT FROM AUTHOR]

The optical and electrical properties of FeSe thin films are studied by both optical absorption and Hall measurements, which suggest that ferromagnetic FeSe is a metal instead of a semiconductor. No absorption gap is observed in the whole spectrum range from far infrared to ultraviolet. Temperature dependent transport measurement indicates that FeSe has a resistivity about 10-3 Ω cm. It is also found that there is a transition from n-type conductivity at low temperatures to p-type conductivity at higher temperatures in FeSe, which is attributed to the two-carrier transport nature and the thermal activation of localized carriers in the thin film. [ABSTRACT FROM AUTHOR]

Electron motion in a cylindrical chamber under RF electric field and confronting divergent magnetic fields was simulated to evaluate the phase-resolved profiles of power deposition to electrons in a low-pressure inductively coupled magnetized plasma. There were three primary regions where the power deposition was high; a region near the RF antenna, a region near the sidewall, and a region of the partial resonance. The phase-resolved profiles of the electron energy gain G(t) and azimuthal electron velocity vθ(t) were obtained in every section defined in the chamber, and were fitted by functions with sinusoidal terms. The characteristics of G(t) and vθ(t), e.g. their asymmetry and directionality, particular to the position were discussed by comparisons between different regions with the fitting parameters and their factors, such as the amplitude of electric field, that of the azimuthal velocity, the power factor, and the phase differences from the RF electric field. [ABSTRACT FROM AUTHOR]

The periodic variation of the average electron velocity vector under crossed ac electric and dc magnetic fields is formulated analytically on the basis of kinetic equations for single-electron motion assuming constant-collision-frequency models with and without ionization. The velocity vector draws elliptic loci with the alternation of the electric field, and this is verified by Monte Carlo simulations. The amplitude and the mean deflection angle of the velocity vector, which represent basic features of electron transport in magnetized plasmas, are explicitly described with the collision frequency, the ac angular frequency, and the intensities of the fields. [ABSTRACT FROM AUTHOR]

We report a measurement of the flux-integrated |$\nu_{\mu}$| charged-current cross sections on water, hydrocarbon, and iron in the T2K on-axis neutrino beam with a mean neutrino energy of 1.5 GeV. The measured cross sections on water, hydrocarbon, and iron are |$\sigma^{\rm{H_{2}O}}_{\rm{CC}} = (0.840\pm 0.010(\mathrm{stat.})^{+0.10}_{-0.08}(\mathrm{syst.}))\times10^{-38}\,\mathrm{cm}^2$| /nucleon, |$\sigma^{\rm{CH}}_{\rm{CC}} = (0.817\pm 0.007(\mathrm{stat.})^{+0.11}_{-0.08}(\mathrm{syst.}))\times10^{-38}\,\mathrm{cm}^2$| /nucleon, and |$\sigma^{\rm{Fe}}_{\rm{CC}} = (0.859\pm 0.003(\mathrm{stat.})^{+0.12}_{-0.10}(\mathrm{syst.}))\times10^{-38}\,\mathrm{cm}^2$| /nucleon, respectively, for a restricted phase space of induced muons: |$\theta_{\mu}<45^{\circ}$| and |$p_{\mu}>$| 0.4 GeV/ |$c$| in the laboratory frame. The measured cross section ratios are |${\sigma^{\rm{H_{2}O}}_{\rm{CC}}}/{\sigma^{\rm{CH}}_{\rm{CC}}} = 1.028\pm 0.016(\mathrm{stat.})\pm 0.053(\mathrm{syst.})$|⁠ , |${\sigma^{\rm{Fe}}_{\rm{CC}}}/{\sigma^{\rm{H_{2}O}}_{\rm{CC}}} = 1.023\pm 0.012(\mathrm{stat.})\pm 0.058(\mathrm{syst.})$|⁠ , and |${\sigma^{\rm{Fe}}_{\rm{CC}}}/{\sigma^{\rm{CH}}_{\rm{CC}}} = 1.049\pm 0.010(\mathrm{stat.})\pm 0.043(\mathrm{syst.})$|⁠. These results, with an unprecedented precision for the measurements of neutrino cross sections on water in the studied energy region, show good agreement with the current neutrino interaction models used in the T2K oscillation analyses. [ABSTRACT FROM AUTHOR]

Single-electron motions near the chamber wall of a type of inductively coupled magnetized plasmas were analyzed using a Monte Carlo method to understand the mechanism of electron energy gain (EEG). The analysis revealed a counterintuitive mechanism that electron reflection promotes the EEG in the presence of E × B drifts and collisional scattering. Distributions of EEG, energy loss, and mean electron energy were calculated using a simplified flat wall model at various strengths of electric and magnetic fields and remaining energy ratios at specular and diffuse reflections. A high stochastic EEG was observed near the wall clearly at high electric and weak magnetic fields not only in the elastic specular reflection model but also in the inelastic diffuse reflection model. An effect of boundary on the EEG mechanism was explained from the viewpoint of microscopic electron behavior. [ABSTRACT FROM AUTHOR]

The electron motion under confronting divergent magnetic fields (CDMFs) applied to inductively coupled plasmas was simulated using a Monte Carlo method. The CDMFs induced by two coaxial dc coils confined electrons in one side of the separatrix of the CDMFs. However, electrons diffused across the separatrix mainly in two ways. One was the displacement of their gyrocenters due to scattering near the outer part of the separatrix. This process tended to occur for high-energy electrons with correspondingly large gyroradii. The other was passage through the weak magnetic field around the center. This process was allowed for low-energy electrons. The position-dependent selectivity about the electron energy was pointed out as a seed property for applications of the separatrix as a magnetic filter or shutter. The mechanism by which the functions of the separatrix emerge was explained from a viewpoint of electron motion under the CDMFs. [ABSTRACT FROM AUTHOR]