305 research outputs found

    Influence of salicylic acid on phytochelatin synthesis in Zea mays during Cd stress

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    Abstract: Presoaking maize (Zea mays) seeds in salicylic acid (SA) reduces damage caused by cadmium. In the present work the possible role of phytochelatins (PCs) in SA-mediated protection against Cd toxicity was investigated. Seeds were presoaked in 0.5 mM SA, and seedlings were grown in hydroponic solution containing 0, 0.01, 0.015, or 0.025 mM Cd. Treatment with Cd increased the PC levels in maize roots, but only slight changes were observed in the leaves. Long-term exposure to Cd decreased the phytochelatin synthase (PCS) activity in the roots and led to an increase in PCS and glutathione reductase (GR) activities in maize leaves. Although presoaking seeds in SA solution before exposure to Cd may reduce the level of heavy metal injury and has an effect on the composition of individual PCs, this protection is not directly connected with the altered regulation of PCs

    REHABILITATION AFTER STROKE: TRADITION AND FUTURE

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    The measurement of the structural disorders after stroke can be carried out by estimating the personal deficit and then generalized as a degree of invalidity. The present study focused on 65 stroke patients. They were follow Д d-up and underwent an early neurorehabilitation course. The analysis of an extensive body of literature and the results obtained from our clinical investigations enabled to discuss the relationship between the elements, e. g., diagnosis, planning, intervention and assessment involved in the management of the neurorehabilitation process. Based on the combination of standardized indices and scales the authors suggest a unified rehabilitation profile enabling them to evaluate and monitor the motor and cognitive deficit. Thus, objective prerequisites are established for determining the priorities, monitoring the efficacy and the possibilities for prognosis of terms and outcome of the conducted rehabilitation training

    Turbulence in Magnetic Reconnection Jets from Injection to Sub-Ion Scales

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    We investigate turbulence in magnetic reconnection jets in the Earth's magnetotail using data from the Magnetospheric Multiscale spacecraft. We show that fully developed turbulence is observed in many reconnection jets. The observed turbulence develops on the time scale of a few ion gyroperiods, resulting in intermittent multifractal energy cascade from the characteristic scale of the jet down to the ion scales. We show that at sub-ion scales, the fluctuations are close to mono-fractal and predominantly kinetic Alfv\'en waves. The observed energy transfer rate across the inertial range is the largest reported for space plasmas so far

    Common and distinct lateralised patterns of neural coupling during focused attention, open monitoring and loving kindness meditation

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    Meditation has been integrated into different therapeutic interventions. To inform the evidence-based selection of specific meditation types it is crucial to understand the neural processes associated with different meditation practices. Here we explore commonalities and differences in electroencephalographic oscillatory spatial synchronisation patterns across three important meditation types. Highly experienced meditators engaged in focused attention, open monitoring, and loving kindness meditation. Improving on previous research, our approach avoids comparisons between groups that limited previous findings, while ensuring that the meditation states are reliably established. Employing a novel measure of neural coupling – the imaginary part of EEG coherence – the study revealed that all meditation conditions displayed a common connectivity pattern that is characterised by increased connectivity of (a) broadly distributed delta networks, (b) left-hemispheric theta networks with a local integrating posterior focus, and (c) right-hemispheric alpha networks, with a local integrating parieto-occipital focus. Furthermore, each meditation state also expressed specific synchronisation patterns differentially recruiting left- or right-lateralised beta networks. These observations provide evidence that in addition to global patterns, frequency-specific inter-hemispheric asymmetry is one major feature of meditation, and that mental processes specific to each meditation type are also supported by lateralised networks from fast-frequency bands

    On the regional variability of dB/dt and its significance to GIC

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    Faraday's law of induction is responsible for setting up a geoelectric field due to the variations in the geomagnetic field caused by ionospheric currents. This drives geomagnetically induced currents (GICs) which flow in large ground‐based technological infrastructure such as high‐voltage power lines. The geoelectric field is often a localized phenomenon exhibiting significant variations over spatial scales of only hundreds of kilometers. This is due to the complex spatiotemporal behavior of electrical currents flowing in the ionosphere and/or large gradients in the ground conductivity due to highly structured local geological properties. Over some regions, and during large storms, both of these effects become significant. In this study, we quantify the regional variability of dB/dt using closely placed IMAGE stations in northern Fennoscandia. The dependency between regional variability, solar wind conditions, and geomagnetic indices are also investigated. Finally, we assess the significance of spatial geomagnetic variations to modeling GICs across a transmission line. Key results from this study are as follows: (1) Regional geomagnetic disturbances are important in modeling GIC during strong storms; (2) dB/dt can vary by several times up to a factor of three compared to the spatial average; (3) dB/dt and its regional variation is coupled to the energy deposited into the magnetosphere; and (4) regional variability can be more accurately captured and predicted from a local index as opposed to a global one. These results demonstrate the need for denser magnetometer networks at high latitudes where transmission lines extending hundreds of kilometers are present

    Intermittent turbulence, noisy fluctuations and wavy structures in the Venusian magnetosheath and wake

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    Recent research has shown that distinct physical regions in the Venusian induced magnetosphere are recognizable from the variations of strength of the magnetic field and its wave/fluctuation activity. In this paper the statistical properties of magnetic fluctuations are investigated in the Venusian magnetosheath and wake regions. The main goal is to identify the characteristic scaling features of fluctuations along Venus Express (VEX) trajectory and to understand the specific circumstances of the occurrence of different types of scalings. For the latter task we also use the results of measurements from the previous missions to Venus. Our main result is that the changing character of physical interactions between the solar wind and the planetary obstacle is leading to different types of spectral scaling in the near-Venusian space. Noisy fluctuations are observed in the magnetosheath, wavy structures near the terminator and in the nightside near-planet wake. Multi-scale turbulence is observed at the magnetosheath boundary layer and near the quasi-parallel bow shock. Magnetosheath boundary layer turbulence is associated with an average magnetic field which is nearly aligned with the Sun-Venus line. Noisy magnetic fluctuations are well described with the Gaussian statistics. Both magnetosheath boundary layer and near shock turbulence statistics exhibit non-Gaussian features and intermittency over small spatio-temporal scales. The occurrence of turbulence near magnetosheath boundaries can be responsible for the local heating of plasma observed by previous missions

    Standard SANC modules for NLO QCD Radiative Corrections to Single-top Production

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    It this paper we present the results obtained with the newly created Standard SANC modules for calculation of the NLO QCD corrections to single top production processes in s and t channels at the partonic level, as well as top-decays. The main aim of these results is to prove the correct work of modules. A comprehensive comparison with results of the CompHEP system is given, where possible. These modules are intended to be used in Monte Carlo generators for single top production processes at the LHC. As in our recent paper, devoted to the electroweak corrections to these processes, we study the regularization of the top-legs associated infrared divergences with aid of the complex mass of the top quark. A comparison of QCD corrections with those computed by the conventional method is presented both for top production and decays. For s channel production we give an analytic proof of equivalence of the two methods in the limit of low top width.Comment: 21 pages, 2 figures, 17 table
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