Electron Pressure Research Articles

The Current Tension Electric Field in the Generalized Ohm's Law

AbstractIn the prevailing form of the generalized Ohm's law (GOL), is often neglected. Because of the resemblance to the magnetic tension, we refer to this term as the current tension electric field (ECT). Our theoretical analysis reveals that ECT with a characteristic length of dominates the electron inertia terms in the electron diffusion region (EDR) and is comparable to the electron pressure term in low‐βe conditions. Using particle‐in‐cell simulations, we demonstrate that ECT can contribute significantly to the reconnection electric field and energy dissipation at the boundaries of the inner EDR and in the outer EDR. Positive and negative J ⋅ ECT can be used to identify inner and outer electron diffusion regions, respectively.

A 0D parallel transport model for varying density regimes for use in 2D drift‐fluid turbulence codes

AbstractIn this paper, a new model of the parallel transport in 2D drift‐fluid turbulence codes is formulated as a 3‐point model and benchmarked against SOLPS‐ITER. The model allows for the existence of parallel temperature gradients and local recycling near the target. To realize this, the volume of the flux tube is split into two zones: (1) a connection zone extending from the outer midplane to the ionization zone entrance and (2) an ionization zone covering the remaining space until the sheath edge. By assuming a linear increase of the parallel particle and conductive heat fluxes in the connection zone, and assuming an ad‐hoc relation for the electron pressure evolution, expressions for the plasma fields at the entrance of the ionization zone are obtained. The evaluation of the integral balances over the ionization zone leads to an implicit system in terms of the parallel fluxes. To benchmark the model, we compare with reference data from density, current and recycling scans for a flux tube with SOLPS‐ITER. From these scans, one observes that the model predicts well the parallel particle flux in the density and recycling scans. Discrepancies that arise at higher densities for both the conductive heat fluxes and the required floating upstream potential are analyzed and partly explained by the superlinear evolution of the heat fluxes in the SOLPS‐ITER simulations. It is concluded that the model can be used to construct the effective volumetric sink terms in 2D drift‐fluid turbulence models.

Recent Progress in MEMS Fiber-Optic Fabry-Perot Pressure Sensors.

Pressure sensing plays an important role in many industrial fields; conventional electronic pressure sensors struggle to survive in the harsh environment. Recently microelectromechanical systems (MEMS) fiber-optic Fabry-Perot (FP) pressure sensors have attracted great interest. Here we review the basic principles of MEMS fiber-optic FP pressure sensors and then discuss the sensors based on different materials and their industrial applications. We also introduce recent progress, such as two-photon polymerization-based 3D printing technology, and the state-of-the-art in this field, e.g., sapphire-based sensors that work up to 1200 °C. Finally, we discuss the limitations and opportunities for future development.

Mass bias in clusters of galaxies: Projection effects on the case study of Virgo replica

When measuring the observed pressure, density, or temperature profiles of the intracluster gas, and hence the mass of clusters of galaxies, projection effects or departures from the spherical symmetry hypothesis may induce biases. To estimate how strongly the cluster’s observed properties depend on the direction of observation, we use a constrained hydrodynamical simulation of the Virgo cluster that replicates the actual cluster of galaxies. In this case study, we analysed Virgo properties when projected in different directions, including along the Milky Way-Virgo axis, which mimics our observation direction. We compared the hydrostatic mass and the hydrostatic mass bias from the projection along the different observation directions to that derived from the 3D simulation. We show that projection effects impact the determination of Virgo mass. We particularly demonstrate that the mass and pressure along the line of sight correlate with the 2D- and 3D-deprojected electron density and pressure profiles intensity and thus impact the derived hydrostatic mass. We also show that the deviations to the hydrostatic equilibrium induced by pressure discontinuities within the cluster are emphasised by the deprojection process and thus make the hydrostatic mass estimation invalid at these radii.

Superthermal Electron Observations at Mars During the December 2022 Disappearing Solar Wind Event

AbstractOn 26–27 December 2022, Mars experienced an extremely low‐density solar wind stream, which was encountered first by Earth because of the radial alignment of the two planets (i.e., Mars opposition). During this event, two important properties of the ionospheric and magnetospheric states changed significantly in response to the low solar wind ram pressure, as inferred from the superthermal electron observations from the Mars Atmospheric and Volatile EvolutioN (MAVEN) mission. The interface between the ionosphere and magnetosphere expanded to thousands of kilometers, outside of the nominal bow shock locations, coinciding with the expansion of the cold planetary ions. Meanwhile, the ambipolar electrostatic potential arising from the ionospheric electron pressure gradient increased from the nominal ∼ −0.7 to ∼ −2 V (relative to the lower ionosphere). This enhanced ambipolar potential likely facilitated the observed ionosphere expansion.

Inter-discharge optimization for fast, reliable access to ASDEX Upgrade advanced tokamak scenario

Rapid inter-discharge simulation and optimization using the RAPTOR code have allowed the development of a reliable and reproducible early heating strategy for an advanced tokamak (AT) scenario on ASDEX Upgrade. Solving for electron heat and current diffusion in RAPTOR with ad-hoc formulas for heat transport and electron cyclotron current drive (ECCD) efficiency is found to robustly recover the coupled dynamics of Te and q, while maintaining model parameters fixed for all discharges. The pedestal top boundary condition in pre-shot simulations is set by a newly derived scaling law for the electron pressure at ρ = 0.8, using a data set of previous AT discharges. RAPTOR simulations have allowed to develop an understanding of the onset of 3/2 tearing modes, which were observed to have a detrimental impact on confinement when low magnetic shear conditions are present at the rational surface during the high-β phase. Delaying the NBI heating, by a specific time interval found via simulations, has led to avoiding these modes. A non-linear optimization scheme has been applied to optimize the ECCD deposition radii to reach a stationary state with qmin>1 at the beginning of the flat-top phase, while ensuring a non-zero magnetic shear at q = 1.5 throughout the high-β phase, and has been successfully tested in experiment. However, further experiments, aiming for qmin>1.5 , have highlighted limitations of the present feedforward control approach in the presence of shot-to-shot variations that are not included in the applied model. Application of real-time model-based control is proposed to overcome model-reality mismatches in future work.

Ion acceleration from the interaction of ultrahigh-intensity laser pulses with near-critical density, nonuniform gas targets

Using one-dimensional, long-timescale particle-in-cell simulations, we study the processes of ion acceleration from the interaction of ultraintense (1020 W cm−2), ultrashort (30 fs) laser pulses with near-critical, nonuniform gas targets. The considered initially neutral, nitrogen gas density profiles mimic those delivered by an already developed noncommercial supersonic gas shock nozzle: they have the generic shape of a narrow (20 μm wide) peak superimposed on broad (∼1 mm, ∼180 μm scale length), exponentially decreasing ramps. While keeping its shape constant, we vary its absolute density values to identify the interaction conditions leading to collisionless shock-induced ion acceleration in the gas density ramps. We find that collisionless electrostatic shocks (CES) form when the laser pulse is able to shine through the central density peak and deposit a few 10% of its energy into it. Under our conditions, this occurs for a peak electron density between 0.35 nc and 0.7 nc. Moreover, we show that the ability of the CES to reflect the upstream ions is highly sensitive to their charge state and that the laser-induced electron pressure gradients mainly account for shock generation, thus highlighting the benefit of using sharp gas profiles, such as those produced by shock nozzles.

Prevalence of Pre-diabetes, Diabetes and Associated Risk Factors among Staff and Students of Federal Polytechnic, Kaura-Namoda

Obesity and overweight are major public health issues worldwide. This study was aimed at assessing the prevalence of diabetes and its associated risk factors among the staff and students of Federal Polytechnic Kaura-Namoda. A total of 159 participants took part in the study, consisting of 60 staff and 99 students. Anthropometric measurement and the World Health Organization’s (WHO) cut-offs were used to classify body weight into underweight, normal weight, overweight and obesity. Fasting blood glucose (FBG) level was determined using glucometer. Blood pressure was measured using an electronic blood pressure monitor. The overall prevalence of diabetes was 2.5%, with 2.0% being known cases and 0.5% newly diagnosed individuals. The prevalence of diabetes was higher in staff (2%) than in students (0.5%). The prevalence of pre-diabetes was 5.7%, with 4.4% occurring in staff and 1.3% in students. While the prevalent overweight and obesity were 51% and 23.9% respectively, among the participants, with students being more affected than staff. Hypertension was found in males (1.9%) and none in females. Also, pre-hypertension was more prevalent in students (32%) than in staff (0%). Pre-diabetes was more prevalent in overweight, obese, hypertensive, and 40 years or above participants. There was a correlation between diabetes and age, obesity, and hypertension. In conclusion, low prevalence of overweight, obesity, hypertension, and diabetes were found among the staff and students of Federal Polytechnic Kaura Namoda. The adoption of regular physical exercise, healthy eating habits, and a healthy lifestyle is therefore recommended among the staff and students for improved health status.

Intense Magnetic Reconnection Process Embedded in Three‐Dimensional Turbulent Current Sheet

AbstractRecent magnetospheric observations and three‐dimensional (3D) kinetic simulations have shown that plasma wave activities are significantly enhanced around the reconnection x‐line, implying that the reconnection process is fully 3D. However, how the turbulence affects the local reconnection process has been poorly understood so far. We find by means of large‐scale particle‐in‐cell simulation in 3D system that the local reconnection rate can be significantly enhanced, reaching 0.4, which is much larger than theoretical predictions for two‐dimensional (2D) reconnection. The large reconnection rate is associated with large energy conversion rate and strong electron acceleration. The enhancement of the reconnection rate is caused by local increases of electron momentum transport and pressure gradient force induced by turbulence, which can not occur in 2D system. The result is expected to give better interpretations to in‐situ satellite observations where magnetic reconnection proceeds in 3D system.

Gyrokinetic turbulence modeling of a high performance scenario in JT-60SA

Local gyrokinetic simulations are used to model turbulent transport for the first time in a representative high-performance plasma discharge projected for the new JT-60SA tokamak. The discharge features a double-null separatrix, 41 MW of combined neutral beam heating and electron cyclotron heating, and a high predicted ratio of the normalized plasma kinetic to magnetic pressure β. When considering input parameters computed from reduced transport models, gyrokinetic simulations predict a turbulent heat flux well below the injected 41 MW. Increasing the background gradients, on the other hand, can trigger a non-zonal transition (NZT), causing heat fluxes to no longer saturate. Furthermore, when considering fast ions in the simulations, a high-frequency mode is destabilized that substantially impacts the turbulence. The NZT is avoided by reducing the electron pressure by 10% below its nominal value, and the fast-ion resonance is removed by reducing the fast-ion temperature. The thus-obtained simulation features broadband frequency spectra and density and temperature fluctuation levels δn/n≈1% –2%, δT/T≈1% –6% that should be measurable with fluctuation diagnostics planned for JT-60SA. The temperature profile is fixed by the critical main-ion temperature gradient as a consequence of the high stiffness; heat fluxes increase by a factor of ten when increasing the main ion temperature gradient by 17%. Despite large gradients, it is demonstrated that, due to the large β, retaining compressional magnetic field fluctuations and in particular, the contribution of the pressure gradient in the ∇B drifts, is crucial to achieving non-zero heat fluxes.

Title: Risk Factors and Natural History of Vincristine Induced Neuropathy on UKALL 2011: A Randomised Controlled Trial of the Effect of Omitting Vincristine Pulses

Introduction UKALL 2011 is a randomised study recruiting children and young adults (up to 25) with Acute Lymphoblastic Leukaemia (ALL) or Lymphoblastic Lymphoma (LBL). One of the aims of the trial was to reduce maintenance morbidity by randomising to Vincristine (VCR)/dexamethasone pulses or not. Results of this randomisation were presented at ASH 2022. In a sub-study, we also aimed to determine the natural history of vincristine induced neuropathy (VIN), including patients randomised to vincristine in maintenance or not and to determine pharmacogenomic risk factors for VIN. Methods Children and adolescents, aged 5-18yrs, were recruited from 5 centres in the UK. Patients were stratified by NCI risk, cytogenetics and end of induction MRD to receive Regimens A (NCI standard risk, MRD low risk), B (NCI high risk, MRD low risk) or C (Cytogenetic poor risk or MRD intermediate risk regardless of NCI risk). The maximum total number of vincristine doses was dependent on regimen and gender: females - Regimen A/B 33, Regimen C 42; males Regimen A/B 46, Regimen C 55. VIN was assessed at 7 time points (diagnosis, end of induction, delayed intensification, maintenance cycles 1,3 & 5 and end of treatment) using the Paediatric TNSr-Vincristine. The Paediatric TNSr-Vincristine assessed proximal extension of numbness, vibration, temperature sensation, muscle strength, tendon reflexes, constipation and hoarseness with each item scored from 0-4, with higher scores indicating more severe neuropathy (n=67). To assess how walking was affected, gait assessment was completed using the GAITRite® walkway-a mat embedded with several thousand electronic pressure sensors activated by mechanical pressure that captured key walking outcomes (velocity, cadence and step length) (n=46). The gait parameters were analysed and compared with age and gender matched controls enabling Z-scores comparison to normal controls. Nine candidate SNPs associated with VIN were genotyped (n=58) and were analysed against highest TNS score at any timepoint and TNS scores above and below the mean. 39 children were randomised to vincristine or not (20 vincristine vs. 19 no vincristine). We fitted linear mixed-effects regression. Predictive factors included genetics; treatment time point; post induction regime (C vs A/B). For the randomised cohort the effect of pulsed vincristine was explored. All tests were two-sided, with significance determined as p<0.05. We adjusted the effects in the model to accommodate effect of age and gender on the total neuropathy score for paediatrics. Analyses were performed using R version 4.3.1. Results Compared to diagnosis, the likelihood of VIN increased between end of induction and intensification, and then reduced over subsequent visits, but remained significantly abnormal at end of treatment (TNS incident rate ratio (IRR) 6.2 (end of induction/intensification vs diagnosis); 4.1 (end of treatment vs diagnosis); p<0.001) (Fig 1). Older children were more likely to have a higher TNS score (IRR 2.4 (p=0.003). Velocity, cadence and step length data were significantly affected compared to normal standards ( p<0.001; Figure 2). Regimen C led to a reduction in step length Z-score of a third ((L) p=0.05; (R) p=0.03)). The likelihood of a higher VIN score in patients randomised to pulsed vincristine in maintenance compared to no vincristine was borderline significant (TNS score (IRR) 1.31 with a confidence interval of 1.00-1.71 (p=0.05)).When analysed by ABCB1 haplotype, TTT/TTT carrier status (loci rs1045642, rs1128503 and rs2032582) was significantly associated with lower TNS scores (p=0.04), whilst the CEP72 TT genotype was significantly associated with TNS scores below the mean (p=0.03) in contrast to previous literature and the ABCB1 rs2032582 G allele was associated with significantly higher mean TNS scores (p=0.04) Conclusion VIN increases with intensity of vincristine treatment and does not normalise at the end of treatment. VIN led to a slower gait and shorter steps whilst removing vincristine in maintenance was associated with reduced likelihood of VIN. VIN was not strongly influenced by any single genotype in this cohort. Conflicting pharmacogenomics results could be explained by differences in ethnicity, protocol design and relatively small numbers in this analysis. Gait analysis represents a novel functional method of assessing VIN enabling comparison to normal age matched peers.

On a plasma sheath with a small normal magnetic field separating regions of oppositely directed magnetic field

The Harris-sheet model provides an elegant solution to the kinetic plasma equation for a steady state 1D current sheet geometry separating regions with oppositely directed magnetic field. However, adding just a small normal magnetic field to the Harris configuration yields thermal streaming of particles into and out of the current sheet, fundamentally changing the form of its kinetic description. The action variable, Jz, associated with the oscillatory orbit motion perpendicular to the current sheet is well conserved and can be applied for solving the kinetic equation in the 1D sheet geometry that includes a small normal magnetic field. Revisiting this problem, we develop a new formalism that permits numerical solutions to be readily obtained for general upstream/asymptotic electron and ion distributions. In particular, we consider the case of isotropic ion pressure and anisotropic bi-Maxwellian electrons. The current sheets are then supported by electron pressure anisotropy. Furthermore, the total current across a particular sheet is set by the fire-hose condition based on the electron pressures normalized by the asymptotic magnetic field pressure. Analytical approximations are obtained for the numerical solutions expressed in terms of the asymptotic electron temperature anisotropy and the ion temperature. We discuss a preliminary application of the framework to the electron diffusion region of anti-parallel magnetic reconnection.

Effects of high-power pain threshold ultrasound technique in patients with knee osteoarthritis: A single-blind randomized controlled trial

Osteoarthritis (OA) is a highly prevalent, degenerative disease of the joints manifested by joint pain, tenderness, decreased function, and limited range of motion (ROM). The current study aimed at evaluating the therapeutic effect of the high-power pain-threshold ultrasound technique (HPPTUS) in comparison with conventional ultrasound (US) techniques in patients with knee osteoarthritis (KOA). A single-masked, pre–post randomized controlled trial was conducted. Fifty participants of both sexes (between 40 and 50 years of age), diagnosed with stage II knee osteoarthritis, participated in this study. They were randomized into two groups: Group A (experimental group, n=25), which received HPPTUS on the knee joint in addition to the traditional treatment (hot packs and isometric exercise for quadriceps), and Group B (control group, n=25), which received conventional ultrasound on knee joint in addition to the traditional treatment (hot packs and isometric exercise for quadriceps). Both groups underwent a four-week treatment plan in which sessions were conducted twice per week. The visual analogue scale (VAS) was used to estimate the intensity of pain, Digital Electronic Pressure Algometer was used to measure pressure pain threshold (PPT) on trigger point around knee, and Digital goniometer was utilized to assess ROM of the knee joint before and after treatment. The MANOVA test revealed statistically significant improvements in all variables (VAS, PPT, knee ROM) post-treatment compared to pre-treatment values in the HPPTUS group (experimental group) (p < 0.05), while the control group revealed statistically significant improvement only in VAS post-treatment compared with pre-treatment (p < 0.05). Comparison between groups revealed statistically significant improvements in VAS, PPT, knee ROM in participants receiving HPPTUS compared with the control group (p < 0.05). High-power ultrasound can be effectively implemented in the treatment of knee OA as it produces significant improvements in the intensity of pain, pressure-pain threshold, and knee joint ROM.

PSI Photoinhibition and Changing CO2 Levels Initiate Retrograde Signals to Modify Nuclear Gene Expression.

Photosystem I (PSI) is a critical component of the photosynthetic machinery in plants. Under conditions of environmental stress, PSI becomes photoinhibited, leading to a redox imbalance in the chloroplast. PSI photoinhibition is caused by an increase in electron pressure within PSI, which damages the iron-sulfur clusters. In this study, we investigated the susceptibility of PSI to photoinhibition in plants at different concentrations of CO2, followed by global gene expression analyses of the differentially treated plants. PSI photoinhibition was induced using a specific illumination protocol that inhibited PSI with minimal effects on PSII. Unexpectedly, the varying CO2 levels combined with the PSI-PI treatment neither increased nor decreased the likelihood of PSI photodamage. All PSI photoinhibition treatments, independent of CO2 levels, upregulated genes generally involved in plant responses to excess iron and downregulated genes involved in iron deficiency. PSI photoinhibition also induced genes encoding photosynthetic proteins that act as electron acceptors from PSI. We propose that PSI photoinhibition causes a release of iron from damaged iron-sulfur clusters, which initiates a retrograde signal from the chloroplast to the nucleus to modify gene expression. In addition, the deprivation of CO2 from the air initiated a signal that induced flavonoid biosynthesis genes, probably via jasmonate production.

Portable light weight open tubular ion chromatograph for field determination of environmental anions

We report a battery powered non-suppressed open tubular ion chromatograph (NSOTIC) that weighs less than 3 kg with on-board rechargeable lithium-ion batteries that provide power for 18 h of operation. It is contained in an aluminum case measuring 30 × 25 × 16 cm. Separation relies on open tubular (OT) chromatographic columns which eliminate the need for high pressure pumps, drastically reducing weight and complexity. Eluent consumption is less than 100 µL per separation. Eluent is supplied from a pressurized vessel via a voltage-controlled electronic pressure controller. Flow rates are typically <200 nL/min which allows a single 16–20 g gas cartridge to perform hundreds of separations. Two anions, chloride and nitrate, in Atacama soil samples were field determined by running the portable NSOTIC. More samples were lab analyzed by commercial IC and IC/MS-MS (only perchlorate due to its low concentration level). To demonstrate the feasibility of running NSOTIC on sample analysis, samples were tested by both non-portable and portable NSOTIC.

Comparative Analysis of the Effects of Sport and Music on the Respiratory System

It is known that the respiratory system develops in response to exercise. However, it is not clear whether sport or music has a greater effect. The aim of this study was to investigate whether different types of sport and music have a greater effect on the development of the respiratory system. Individuals who continued their active sports and music life, who exercised regularly at least 3 days a week and whose FEV1/FVC ratio was above 75% were included in the study, while individuals with a history of lung disease, upper respiratory disease and less than 6 years of experience were excluded from the study. MGC Diagnostics brand spirometry was used to measure forced expiratory volume in one second (FEV1), FEV1/FVC, forced vital capacity (FVC), slow vital capacity (SVC), inspiratory capacity and maximal volumetric capacity, maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP) and MicroRPM (Kent, UK) electronic respiratory pressure device. In our study, basketball players had higher respiratory muscle strength than opera singers (p&amp;lt;0.05). Differences were found in pulmonary function tests for forced vital capacity, forced expiratory volume in one second, slow vital capacity and maximal voluntary volume (p&amp;lt;0.05). It was observed that athletes had higher values in pulmonary function tests (FVC, FEV1, SVC, MVV) and maximal inspiratory MIP and MEP parameters than musicians (p&amp;lt;0.05). Therefore, exercise has a greater effect on the respiratory system than music.

METHOD DEVELOPMENT AND VALIDATION OF DIMETHYL SULPHATE CONTENT IN ESOMEPRAZOLE MAGNESIUM DRUG SUBSTANCE BY GC-MS

Dimethyl sulfate is universally used as an alkylating, sulfating and sulfonating agent in organic synthesis; hence it is one of the probable impurities during the synthesis of the esomeprazole magnesium. As per ICH M7, it is genotoxic and mutagenic, so it needs to be controlled as per the acceptable intake of dimethyl sulfate and daily sample dosage. This method validation can be achieved by the hyphenated technique of gas chromatography with mass spectroscopy, which is used to develop the dimethyl sulfate impurity in esomeprazole magnesium drug substance containing salt. The method is achieved with a DB-1 column with electron impact ionization source in sim mode ion under electronic pneumatic pressure control and deliberate oven ramp programming temperature was used. A dissolved, extracted and auto-injection sample was implemented for sample introduction in a splitless mode. Dichloromethane and 2N NaOH was used as a diluent. The calibration curve showed good linearity over the 1.69 to 8.40 ppm (limit: 5.56 ppm) and its correlation coefficient was &gt;0.999. A limit of detection 0.50 ppm and limit of quantitation 1.69 ppm was achieved when the samples were prepared at 50 mg/mL. While recovery proved to be 106.8 to 113.5%, hence it signified the matrix effect.

Two Classes of Equatorial Magnetotail Dipolarization Fronts Observed by Magnetospheric Multiscale Mission: A Statistical Overview

AbstractWe carried out a statistical study of equatorial dipolarization fronts (DFs) detected by the Magnetospheric Multiscale mission during the full 2017 Earth's magnetotail season. We found that two DF classes are distinguished: class I (74.4%) corresponds to the standard DF properties and energy dissipation and a new class II (25.6%). This new class includes the six DF discussed in Alqeeq et al. (2022, https://doi.org/10.1063/5.0069432) and corresponds to a bump of the magnetic field associated with a minimum in the ion and electron pressures and a reversal of the energy conversion process. The possible origin of this second class is discussed. Both DF classes show that the energy conversion process in the spacecraft frame is driven by the diamagnetic current dominated by the ion pressure gradient. In the fluid frame, it is driven by the electron pressure gradient. In addition, we have shown that the energy conversion processes are not homogeneous at the electron scale mostly due to the variations of the electric fields for both DF classes.

Plasma Pressure Distribution of Ions and Electrons in the Inner Magnetosphere During CIR Driven Storms Observed During Arase Era

AbstractUsing Arase observations of the inner magnetosphere during 26 CIR‐driven geomagnetic storms with minimum Sym‐H between −33 and −86 nT, we investigated ring current pressure development of ions (H+, He+, O+) and electron during prestorm, main, early recovery and late recovery phases as a function of L‐shell and magnetic local time. It is found that during the main and early recovery phase of the storms the ion pressure is asymmetric in the inner magnetosphere, leading to a strong partial ring current. The ion pressure becomes symmetric during the late recovery phase. H+ ions with energies of ∼20–50 keV and ∼50–100 keV contribute more to the ring current pressure during the main phase and early/late recovery phase, respectively. O+ ions with energies of ∼10–20 keV contribute significantly during main and early recovery phase. These are consistent with previous studies. The electron pressure was found to be asymmetric during the main, early recovery and late recovery phase. The electron pressure peaks from midnight to the dawn sector. Electrons with energy of &lt;50 keV contribute to the ring current pressure during the main and early recovery phase of the storms. Overall, the electron contribution to the total ring current is found to be ∼11% during the main and early recovery phases. However, the electron contribution is found to be significant (∼22%) in the 03–09 MLT sector during the main and early recovery phase. The results indicate an important role of electrons in the ring current build up.

Correlation between electronic wrist blood pressure with auscultatory blood pressure in children.

The increasing prevalence of obesity in children and adolescents has turned hypertension into an important public health issue. In the current literature, auscultatory blood pressure measurement is recommended for the diagnosis of hypertension. The number of studies comparing electronic blood pressure measurement and auscultatory blood pressure measurement is limited. This study aimed to compare auscultatory blood pressure measurement with electronic blood pressure measurement in the children population group aged 5-15 years. A total of 72 patients aged between 5-15 years without chronic disease were included in the study. Anthropometric measurements (height, weight, body mass index, wrist circumference, mid-upper arm circumference) were performed. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) were first measured electronically from the wrist using an Omron Rs7 Intelli It HEM-6232T device, and then auscultatory measurements were performed. Each type of measurement was performed 3 times intermittently. The mean wrist circumference was 14.43±0.22 cm and the mean mid-upper arm circumference was 21.43±0.55 cm. Mean SBP, DBP and MAP measured electronically on the wrist were 104.1±1.5, 65.6±1.3 and 78.1±1.3 mmHg, respectively, and mean SBP, DBP and MAP measured via auscultation were 99.3±1, 61.4±0.7 and 73.6±0.7 mmHg, respectively. Electronically-measured wrist MAP had significantly moderate correlations with mid-upper arm and wrist circumference (r:0.547, r:0.559, p<0.01). Since the differences were less than 4 mmHg in both systolic and diastolic pressures between electronic wrist blood pressure (EWBP) measurement and auscultatory measurement, it appears that electronic measurement may be important in first line of blood pressure screening. Since it is easy and practical to use in the early period, it may be an alternative approach to auscultatory measurement among non-critical pediatric patients.