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International audience; We report a unique conjugate observation of fast flows and associated current sheet disturbances in the near-Earth magnetotail by MMS (Magnetospheric Multiscale) and Cluster preceding a positive bay onset of a small substorm at ∼14:10 UT, September 8, 2018. MMS and Cluster were located both at X ∼ −14 RE. A dipolarization front (DF) of a localized fast flow was detected by Cluster and MMS, separated in the dawn-dusk direction by ∼4 RE, almost simultaneously. Adiabatic electron acceleration signatures revealed from the comparison of the energy spectra confirm that both spacecraft encounter the same DF. We analyzed the change in the current sheet structure based on multi-scale multi-point data analysis. The current sheet thickened during the passage of DF, yet, temporally thinned subsequently associated with another flow enhancement centered more on the dawnward side of the initial flow. MMS and Cluster observed intense perpendicular and parallel current in the off-equatorial region mainly during this interval of the current sheet thinning. Maximum field-aligned currents both at MMS and Cluster are directed tailward. Detailed analysis of MMS data showed that the intense field-aligned currents consisted of multiple small-scale intense current layers accompanied by enhanced Hall-currents in the dawn-dusk flow-shear region. We suggest that the current sheet thinning is related to the flow bouncing process and/or to the expansion/activation of reconnection. Based on these mesoscale and small-scale multipoint observations, 3D evolution of the flow and current-sheet disturbances was inferred preceding the development of a substorm current wedge.

Accepted: 2019-12-02, 資料番号: SA1190191000

著者人数: 27名, Accepted: 2019-01-15, 資料番号: SA1180269000

著者人数: 18名, Accepted: 2018-11-03, 資料番号: SA1180295000

Space plasma data analysis and mission operations are aided by the categorization of plasma data between different regions of the magnetosphere and identification of the boundary regions between them. Without computerized automation this means sorting large amounts of data to hand-pick regions. Using hand-labeled data created to support calibration of the Fast Plasma Instrument, this task was automated for the MMS mission with 99.9% accuracy. The method partitions the number density and ion temperature plane into sub-planes for each region, fitting boundaries between the sub-planes using a machine learning technique known as the support vector machine. This method presented in this paper is novel because it offers both statistical automation power and interpretability that yields scientific insight into how the task is performed.

著者人数: 19名, Accepted: 2018-07-04, 資料番号: SA1180092000

著者人数: 22名, Accepted: 2016-12-13, 資料番号: SA1170046000

著者人数: 11名, Accepted: 2020-02-21, 資料番号: SA1190234000

著者人数: 20名, Accepted: 2019-05-28, 資料番号: SA1190061000

With the advent of the Heliophysics/Geospace System Observatory (H/GSO), acomplement of multi-spacecraft missions and ground-based observatories to study the space environment, data retrieval, analysis, and visualization of space physics data can be daunting. The Space Physics Environment Data Analysis System (SPEDAS), agrass-roots software development platform (www.spedas.org), is now officially supported by NASA Heliophysics as part of its data environment infrastructure. It serves more than a dozen space missions and ground observatories and can integrate the full complement of past and upcoming space physics missions with minimal resources, following clear, simple, and well-proven guidelines. Free, modular and configurable to the needs of individual missions, it works in both command-line (ideal for experienced users) and Graphical User Interface (GUI) mode (reducing the learning curve for first-time users). Both options have "crib-sheets," user-command sequences in ASCII format that can facilitate record-and-repeat actions, especially for complex operations and plotting. Crib-sheets enhance scientific interactions, as users can move rapidly and accurately from exchanges of technical information on data processing to efficient discussions regarding data interpretation and science. SPEDAS can readily query and ingest all International Solar Terrestrial Physics (ISTP)-compatible products from the Space Physics Data Facility (SPDF), enabling access to a vast collection of historic and current mission data. The planned incorporation of Heliophysics Application Programmer's Interface (HAPI) standards will facilitate data ingestion from distributed datasets that adhere to these standards. Although SPEDAS is currently Interactive Data Language (IDL)-based (and interfaces to Java-based tools such as Autoplot), efforts are under-way to expand it further to work with python (first as an interface tool and potentially even receiving an under-the-hood replacement). We review the SPEDAS development history, goals, and current implementation. We explain its "modes of use" with examples geared for users and outline its technical implementation and requirements with software developers in mind. We also describe SPEDAS personnel and software management, interfaces with other organizations, resources and support structure available to the community, and future development plans.Electronic supplementary materialThe online version of this article (10.1007/s11214-018-0576-4) contains supplementary material, which is available to authorized users.

One of the most important properties of Earth's magnetotail thin current sheet (TCS) is that its current is predominantly contributed by magnetized electrons. The Hall electric field, normal to the TCS and generated by charge separation, is critical to the generation of this electron current as well as a dawn-dusk asymmetry of the magnetotail, such as duskside preference of magnetic reconnection and related structures and phenomena. However, systematic investigation of the Hall electric field has so far been lacking. Utilizing observations of TCS by Magnetospheric Multiscale and Time History of Events and Macroscale Interactions during Substorm spacecraft, we study the properties of this field. Our results, from various, complementary methods, show that the Hall electric field E-z (in the geocentric solar magnetospheric, coordinate system) or E-n (normal to the TCS plane) can be clearly observed to point toward the center of the current sheet. The typical magnitude of this electric field is several tenths of 1 mV/m. Statistics of Magnetospheric Multiscale magnetotail TCS crossings show that the Hall electric field is stronger on the duskside, indicating a stronger Hall effect there, which confirms predictions from global-scale hybrid and particle-in-cell simulations.

Alfv��n vortex is a multi-scale nonlinear structure which contributes to intermittency of turbulence. Despite previous explorations mostly on the spatial properties of the Alfv��n vortex (i.e., scale, orientation, and motion), the plasma characteristics within the Alfv��n vortex are unknown. Moreover, the connection between the plasma energization and the Alfv��n vortex still remains unclear. Based on high resolution in-situ measurement from the Magnetospheric Multiscale (MMS) mission, we report for the first time, distinctive plasma features within an Alfv��n vortex. This Alfv��n vortex is identified to be two-dimensional ($k_{\bot} \gg k_{\|}$) quasi-monopole with a radius of ~10 proton gyroscales. Its magnetic fluctuations $��B_{\bot}$ are anti correlated with velocity fluctuations $��V_{\bot}$, thus the parallel current density $j_{\|}$ and flow vorticity $��_{\|}$ are anti-aligned. In different part of the vortex (i.e., edge, middle, center), the ion and electron temperatures are found to be quite different and they behave in the reverse trend: the ion temperature variations are correlated with $j_{\|}$, while the electron temperature variations are correlated with $��_{\|}$. Furthermore, the temperature anisotropies, together with the non-Maxwellian kinetic effects, exhibit strong enhancement at peaks of $|��_{\|}| (|j_{\|}|)$ within the vortex. Comparison between observations and numerical/theoretical results are made. In addition, the energy-conversion channels and the compressibility associated with the Alfv��n vortex are discussed. These results may help to understand the link between coherent vortex structures and the kinetic processes, which determines how turbulence energy dissipate in the weakly-collisional space plasmas.

著者人数: 26名, Accepted: 2016-04-28, 資料番号: SA1160083000

We investigate the accuracy with which the reconnection electric field E M can be determined from in situ plasma data. We study the magnetotail electron diffusion region observed by National Aeronautics and Space Administration's Magnetospheric Multiscale (MMS) on 11 July 2017 at 22:34 UT and focus on the very large errors in E M that result from errors in an L M N boundary normal coordinate system. We determine several L M N coordinates for this MMS event using several different methods. We use these M axes to estimate E M. We find some consensus that the reconnection rate was roughly E M = 3.2 ± 0.6 mV/m, which corresponds to a normalized reconnection rate of 0.18 ± 0.035. Minimum variance analysis of the electron velocity (MVA‐v e), MVA of E, minimization of Faraday residue, and an adjusted version of the maximum directional derivative of the magnetic field (MDD‐B) technique all produce reasonably similar coordinate axes. We use virtual MMS data from a particle‐in‐cell simulation of this event to estimate the errors in the coordinate axes and reconnection rate associated with MVA‐v e and MDD‐B. The L and M directions are most reliably determined by MVA‐v e when the spacecraft observes a clear electron jet reversal. When the magnetic field data have errors as small as 0.5% of the background field strength, the M direction obtained by MDD‐B technique may be off by as much as 35°. The normal direction is most accurately obtained by MDD‐B. Overall, we find that these techniques were able to identify E M from the virtual data within error bars ≥20%., Key Points The reconnection rate E M is estimated for one event using several techniques to find an M directionThe error bars in E M and the L M N coordinate directions are estimated from virtual dataThe reconnection rate is likely E M = 3.2 mV/m ± 0.6 mV/m, which corresponds to a normalized rate of 0.18 ± 0.035

Three flux ropes associated with near‐Earth magnetotail reconnection are analyzed using Magnetospheric Multiscale observations. The flux ropes are Earthward propagating with sizes from ∼3 to 11 ion inertial lengths. Significantly different axial orientations are observed, suggesting spatiotemporal variability in the reconnection and/or flux rope dynamics. An electron‐scale vortex, associated with one of the most intense electric fields (E) in the event, is observed within one of the flux ropes. This E is predominantly perpendicular to the magnetic field (B); the electron vortex is frozen‐in with E × B drifting electrons carrying perpendicular current and causing a small‐scale magnetic enhancement. The vortex is ∼16 electron gyroradii in size perpendicular to B and potentially elongated parallel to B. The need to decouple the frozen‐in vortical motion from the surrounding plasma implies a parallel E at the structure's ends. The formation of frozen‐in electron vortices within reconnection‐generated flux ropes may have implications for particle acceleration.

著者人数: 16名, Accepted: 2018-02-09, 資料番号: SA1170357000

The gamma irradiation was utilized to facilitate the synthesis of poly (glycerol sebacate)-co-lactic acid (PGS-co-LA). The effect of methyl methacrylate (MMA) crosslinker and varying dosage of irradiation to the structural composition and thermal properties of the synthesized PGS-co-LA was investigated. Compositional analyses of the polymer materials using infrared spectroscopy confirm the covalent formation of ester linkage. The use of methyl methacrylate enhances the formation of the characteristic bonds in the polymer structure. The intensity of these peaks increases with increasing irradiation dosage and high amount of crosslinker. The melting temperature of the PGS-co-LA becomes more negative with the incorporation of high amount of MMA.

著者人数: 19名, Accepted: 2018-01-07, 資料番号: SA1170245000

During a magnetic storm on 23 June 2015, several very intense substorms took place, with signatures observed by multiple spacecraft including DMSP and Magnetospheric Multiscale (MMS). At the time of interest, DMSP F18 crossed inbound through a poleward expanding auroral bulge boundary at 23.5 h magnetic local time (MLT), while MMS was located duskward of 22 h MLT during an inward crossing of the expanding plasma sheet boundary. The two spacecraft observed a consistent set of signatures as they simultaneously crossed the reconnection separatrix layer during this very intense reconnection event. These include (1) energy dispersion of the energetic ions and electrons traveling earthward, accompanied with high electron energies in the vicinity of the separatrix; (2) energy dispersion of polar rain electrons, with a high‐energy cutoff; and (3) intense inward convection of the magnetic field lines at the MMS location. The high temporal resolution measurements by MMS provide unprecedented observations of the outermost electron boundary layer. We discuss the relevance of the energy dispersion of the electrons, and their pitch angle distribution, to the spatial and temporal evolution of the boundary layer. The results indicate that the underlying magnetotail magnetic reconnection process was an intrinsically impulsive and the active X‐line was located relatively close to the Earth, approximately at 16–18 RE., Key Points Simultaneous observations of the PSBL during a strong substorm suggest a near‐tail reconnection site being located at 16–18 RE For the first time, we resolve both energy and pitch angle dispersion of the electron evidence that the boundary layer has temporal originFirst observation of thin energetic electron layers in PSBL with thicknesses of the electron gyroscale

The Magnetospheric Multiscale mission is employed to examine intense Poynting flux directed along the background magnetic field toward Earth, which reaches amplitudes of nearly 2 mW/m(2). The event is located within the plasma sheet but likely near the boundary at a geocentric distance of 9 RE in association with bulk flow signatures. The fluctuations have wavelengths perpendicular to the magnetic field of 124-264 km (compared to an ion gyroradius of 280 km), consistent with highly kinetic Alfven waves. While the wave vector remains highly perpendicular to the magnetic field, there is substantial variation of the direction in the perpendicular plane. The field-aligned Poynting flux may be associated with kinetic Alfven waves released along the separatrix by magnetotail reconnection and/or the radiation of waves excited by bursty bulk flow braking and may provide a means through which energy released by magnetic reconnection is transferred to the auroral region.

We report Magnetospheric Multiscale observations of electron pressure gradient electric fields near a magnetic reconnection diffusion region using a new technique for extracting 7.5 ms electron moments from the Fast Plasma Investigation. We find that the deviation of the perpendicular electron bulk velocity from $E \times B$ drift in the interval where the out-of-plane current density is increasing can be explained by the diamagnetic drift. In the interval where the out-of-plane current is transitioning to in-plane current, the electron momentum equation is not satisfied at 7.5 ms resolution., Comment: 6 pages, 4 figures

Data from the NASA Magnetospheric Multiscale (MMS) mission are used to investigate asymmetric magnetic reconnection at the dayside boundary between the Earth's magnetosphere and the solar wind (the magnetopause). High-resolution measurements of plasmas, electric and magnetic fields, and waves are used to identify highly localized (~15 electron Debye lengths) standing wave structures with large electric-field amplitudes (up to 100 mV/m). These wave structures are associated with spatially oscillatory dissipation, which appears as alternatingly positive and negative values of J dot E (dissipation). For small guide magnetic fields the wave structures occur in the electron stagnation region at the magnetosphere edge of the EDR. For larger guide fields the structures also occur near the reconnection x-line. This difference is explained in terms of channels for the out-of-plane current (agyrotropic electrons at the stagnation point and guide-field-aligned electrons at the x-line).

©2016. American Geophysical Union. All Rights Reserved.We report observations from the Magnetospheric Multiscale satellites of large-amplitude, parallel, electrostatic waves associated with magnetic reconnection at the Earths magnetopause. The observed waves have parallel electric fields (E||) with amplitudes on the order of 100 mV/m and display nonlinear characteristics that suggest a possible net E||. These waves are observed within the ion diffusion region and adjacent to (within several electron skin depths) the electron diffusion region. They are in or near the magnetosphere side current layer. Simulation results support that the strong electrostatic linear and nonlinear wave activities appear to be driven by a two stream instability, which is a consequence of mixing cold (

New Magnetospheric Multiscale (MMS) observations of small‐scale (~7 ion inertial length radius) flux transfer events (FTEs) at the dayside magnetopause are reported. The 10 km MMS tetrahedron size enables their structure and properties to be calculated using a variety of multispacecraft techniques, allowing them to be identified as flux ropes, whose flux content is small (~22 kWb). The current density, calculated using plasma and magnetic field measurements independently, is found to be filamentary. Intercomparison of the plasma moments with electric and magnetic field measurements reveals structured non‐frozen‐in ion behavior. The data are further compared with a particle‐in‐cell simulation. It is concluded that these small‐scale flux ropes, which are not seen to be growing, represent a distinct class of FTE which is generated on the magnetopause by secondary reconnection., Key Points Ion‐scale flux ropes are observed during magnetopause reconnectionThe largely force‐free flux ropes exhibit filamentary currents and nonideal ion behaviorSmall flux content and comparison with simulation indicate a secondary reconnection origin

A library of (meth)acrylamido (co)polymers was prepared by reacting poly(pentafluorophenyl (meth)acrylate) with α-amino, ω-methoxy functionalized di(ethylene glycol), tri(ethylene glycol), and poly(ethylene glycol) (PEG)-350, PEG-750, and PEG-5k, in combination with hexylamine or thyroxine. The resulting copolymers showed an improved solubility in water (higher or absent LCST values) and in alcohols (lower or absent UCST values) than the analogous common series of poly[oligo(ethylene glycol) methyl ether (meth)acrylates]. The polyacrylamido species showed a better solubility than the corresponding polymethacrylamido derivatives of similar molecular weight with all polyacrylamides investigated being water-soluble at temperatures exceeding 90.0 °C. Tunable thermosensitive behavior could be effected by the incorporation of the hydrophobic hexylamide comonomer. Similarly, an acrylamido backbone with grafted oligo(propylene glycol 600) amides exhibited a sharp LCST-type transition around 22.0 °C. The UCST-type...

著者人数: 24名, Accepted: 2017-06-03, 資料番号: SA1170038000

This technical report describes the simple and valuable technique of controlled assisted ridge expansion (CARE) for the esthetic zone of the anterior maxilla. Atrophic bone and narrow alveolar crests make implant bed preparation difficult. The highly predictable surgical technique of CARE for alveolar expansion uses periosteal containment and subperiosteal intrabony vertical releasing incisions efficiently. This allows for the expansion of narrow, anatomically limiting edentulous ridges. The precise and conservative use of Piezosurgery and assisted manipulation of the labialized bony pedicle by horizontal spreaders and rotary osteocondensers affords a highly predictable surgical procedure, which allows implants to be placed at the time of surgery, reducing patient treatment time, morbidity, functional losses, and overall cost, as well as increasing the native bone volume in the atrophic maxillary ridge.

Methyl isopropyl carbinol reactant: 600 g. (4.9 moles) of isopropyl bromide reactant: 200 g. (4.5 moles) of acetaldehyde product: methyl isopropyl carbinol Keywords: Grignard and related reactions

The serial reproducibility of an individual's isokinetic torque was assessed in order to establish a reliable baseline value for future comparison. Thirty-two controls and twenty arthritic patients were tested for their peak isokinetic torque on knee flexion and extension and hip flexion at three velocities on five occasions, at fortnightly intervals. The first test was found to provide a reliable baseline for controls and subjects who could generate a peak torque of 54 Newton meters (Nm) or more. The second test was found to be more representative of the series for groups containing weaker subjects. Variation related to torque: for subjects who generate a peak torque of 54 Nm or more, a range of +/- 20% accommodates the variability of 95% of tests. We conclude that a +/- 20% range applied to either the first or second test, depending on the nature of the group to be studied, serves as a representative baseline value.

To determine the long-range gynecological and histological effects of parenteral progesterone administration during pregnancy, 10 pregnant women, 15-25 years old, were given a total of 500 mg medroxyprogesterone acetate (Depo-Provera) in 100 mg weekly intramuscular injections from Weeks 30-36 of gestation, and compared to 10 other pregnant women as controls during pregnancy and up to 8 weeks postpartum. Prolonged dysfunctional uterine bleeding occurred in 6 out of 11 patients treated with Depo-Provera and did not occur in the controls. Endometrial biopsies at the time of delivery were similar for both groups, but 6-8 weeks postpartum the treated patients showed persistent inactivity. 24-hour urinary excretions of FSH, 17-KS, 17 OHCS, estradiol and estrone were similar for both groups throughout the study as were the Metoprione test for pituitary function and PBI determinations. Urinary excretions of pregnanediol, estriol and total estrogen were lower in the treated patients at the end of pregnancy and postpartum. Evaluation of a larger series of 77 pregnant patients treated with Depo-Provera led to the finding that the drug's effect on the menstrual cycle dissipated within 1 year. 32 of these patients subsequently became pregnant with 28 successful deliveries and 4 spontaneous abortions. Depo-Provera is concluded to cause prolonged ovarian suppression and suppressed placental synthesis of progesterone and estriol.

I think that I shall never see A poem lovely as a tree. Poems are made by fools like me, But only God can make a tree.

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The trees in the streets are old trees used to living with people, Family-trees that remember your grandfather's name.

A connection frequently exists between physical and chemical properties and in many cases recourse must be had to both for an explanation of a phenomenon to which they may each contribute.