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The Arase satellite observed the precipitation of monoenergetic electrons accelerated from a very high altitude above 32,000 km altitude on 16 September 2017. The event was selected in the period when the high‐angular resolution channel of the electron detector looked at pitch angles within ∼5° from the ambient magnetic field direction, and thereby was the first to examine the detailed distribution of electron flux near the energy‐dependent loss cone at such high altitudes. The potential energy below the satellite estimated from the observed energy‐dependence of the loss cone was consistent with the energy of the upgoing ion beams, indicating that ionospheric ions were accelerated by a lower‐altitude acceleration region. The accelerated electrons inside the loss cone carried a significant net field‐aligned current (FAC) density corresponding to ionospheric‐altitude FAC of up to ∼3μA/m2. Based on the anisotropy of the accelerated electrons, we estimated the height of the upper boundary of the acceleration region to be >∼2 RE above the satellite. The height distribution of the acceleration region below the satellite, estimated from the frequency of auroral kilometric radiation, was ∼4,000–13,000 km altitude, suggesting that the very‐high‐altitude acceleration region was separated from the lower acceleration region. Additionally, we observed time domain structure (TDS) electric fields on a subsecond time scale with a thin FAC indicated by magnetic deflections. Such a TDS may be generated by the formation of double layers in the magnetotail, and its potential drop could significantly contribute (∼40%–60%) to the parallel energization of precipitating auroral electrons. Plain Language Summary: The auroral arc is produced by electrons in the magnetosphere accelerated downward by a quasi‐static electric field. The region of the electric field, so called the auroral acceleration region, is typically located just above the ionosphere, at altitudes of a few thousand kilometers. However, recent studies have shown that it can be extended to altitudes higher than 30,000 km. The mechanism and impact of such a very‐high‐altitude acceleration region remain a mystery. The high‐angular resolution electron detector on board the Arase satellite successfully measured current and energy flows carried by the electron accelerated at the very‐high‐altitude acceleration region above the satellite altitude of 32,000 km. This acceleration at very‐high‐altitudes contributed significantly to the energy flow into the ionosphere. Based on the anisotropy of the accelerated electrons, the frequency of auroral kilometric radiation, and the presence of spiky electrostatic waves, we estimate that the very‐high‐altitude acceleration region was located more than 12,000 km above the satellite as a thin charge separation layer, apart from the acceleration region below the satellite. Our results suggest that localized electric fields at very high altitudes, which were not previously associated with the aurora, can energize auroral electrons and affect auroral visibility. Key Points: We comprehensively analyzed a very‐high‐altitude (>32,000 km) auroral acceleration eventNet precipitation of accelerated electrons significantly contributes to the field‐aligned current and energy flux into the ionosphereDouble layers in the magnetotail are possible candidates for very‐high‐altitude auroral accelerations [ABSTRACT FROM AUTHOR]

Although many substorm‐related observations have been made, we still have limited insight into propagation of the plasma and field perturbations in Pi2 frequencies (∼7–25 mHz) in association with substorm aurora, particularly from the auroral source region in the inner magnetosphere to the ground. In this study, we present conjugate observations of a substorm brightening aurora using an all‐sky camera and an inner‐magnetospheric satellite Arase at L ∼ 5. A camera at Gakona (62.39°N, 214.78°E), Alaska, observed a substorm auroral brightening on 28 December 2018, and the footprint of the satellite was located just equatorward of the aurora. Around the timing of the auroral brightening, the satellite observed a series of quasi‐periodic variations in the electric and magnetic fields and in the energy flux of electrons and ions. We demonstrate that the diamagnetic variations of thermal pressure and medium‐energy ion energy flux in the inner magnetosphere show approximately one‐to‐one correspondence with the oscillations in luminosity of the substorm brightening aurora and high‐latitudinal Pi2 pulsations on the ground. We also found their anti‐correlation with low‐energy electrons. Cavity‐type Pi2 pulsations were observed at mid‐ and low‐latitudinal stations. Based on these observations, we suggest that a wave phenomenon in the substorm auroral source region, like ballooning type instability, play an important role in the development of substorm and related auroral brightening and high‐latitude Pi2, and that the variation of the auroral luminosity was directly driven by keV electrons which were modulated by Alfven waves in the inner magnetosphere. Plain Language Summary: One of the most frequent disturbances in the Earth's magnetosphere is called substorm. Through Earth's magnetic field line, the development of a magnetospheric substorm is projected onto Earth's high‐latitude ionosphere as auroral evolution. During a substorm, the energy in the tail of the magnetosphere is released to the earth, and quite a part of this energy is transmitted as different types of wave phenomena. These wave oscillations can be observed by magnetometers on the ground and satellites in the magnetosphere. It is still uncertain what mechanisms trigger these substorm‐related waves, how these waves correlate with other substorm phenomena, and how they transmit and dissipate, especially for the wave phenomena at ∼4–7 Earth radii away from the Earth. This paper presents a case study of such substorm event, where we show the variation of magnetic field and auroral luminosity on the ground, and the electromagnetic wave that is called as Pi2 pulsations and oscillation of plasma flux in the inner magnetosphere. We demonstrate that there are one‐to‐one correspondences in these oscillations. We suggest the possibility that a ballooning plasma instability triggers the observed oscillations in particle flux, as well as the electromagnetic wave that modulates the auroral luminosity. Key Points: Observations of plasma and field characteristics near the source region of a substorm auroral brightening at L ∼ 5Pi2, auroral luminosity variation and fluctuations of in‐situ electromagnetic field and particle flux were observed during substorm onsetCorrespondence between these fluctuations suggest waves in the magnetosphere like ballooning instability control auroral intensity [ABSTRACT FROM AUTHOR]

Auroral brightening is one of the most common phenomena that occur during substorm onset and is usually recognized as a projection of the substorm‐associated magnetospheric plasma dynamics to the ionosphere. However, electromagnetic fields and plasma features associated with the substorm brightening arc have not been well understood. In this study, we present a comprehensive observation of the source plasma and field variations of a substorm brightening aurora in the inner magnetosphere. We performed a unique conjugate observation of a substorm brightening auroral arc observed by a ground‐based camera and by the Arase satellite in the magnetospheric source region at L ∼ 6. The event was observed at Tromsø (69.6°N, 19.2°E), Norway, on 12 October 2017. The brightening arc indicates east‐west structures with longitudinal scales of ∼0.5°–2.0°. Field‐aligned bi‐directional electrons with an energy range between 66 and 1,800 eV were detected by the satellite, simultaneously with the appearance of the brightening arc in the camera. These electrons were probably supplied from the auroral brightening region in the ionosphere, indicating that the satellite was on the same field line of the brightening aurora. The magnetic and electric field data show characteristic fluctuations and earthward Poynting flux around the time that the satellite crossed the aurora. Anti‐phase oscillations between the thermal pressure and the magnetic pressure are also reported. Based on these observations, we suggest the possibility that a ballooning instability occurred in the source region of the substorm brightening arc in the inner magnetosphere at L ∼ 6. Plain Language Summary: A frequently occurring source of variations in the magnetosphere is the substorm, a process that causes energy dissipation into the atmosphere. Substorm is presented as the development of aurorae at high latitudes in the ionosphere. The study of substorm processes helps in understanding the near‐Earth space environment and the space weather. Along Earth's magnetic field lines, the aurora at a latitude of ∼65°N can be traced to ∼4–7 Earth radii away from the Earth at the equatorial plane in space. Using a ground‐based auroral camera, we can construct the correspondence between auroral motion and field and plasma variation at the satellite. This study reports such a unique event of substorm brightening arc observed at Tromsø, Norway, on 12 October 2017. Satellite observed bi‐directional electrons prove the connection between aurora break‐up at ∼100 km altitude and its source region in the magnetosphere at ∼30,000 km away from Earth. Based on the magnetic wave spectrograms, auroral bead‐like structures and other observational results, we suggest the possibility that a ballooning plasma instability occurred in the source region of the substorm brightening arc in the inner magnetosphere. Key Points: Observation of plasma and field features in the source region of a sudden brightening auroral arc during a minor substorm onset at L ∼ 6Energization of particles, field‐aligned electrons, and electromagnetic field fluctuations were observed during the arc crossing by AraseSeveral observational facts indicate the possibility of ballooning instability occurring at this substorm onset [ABSTRACT FROM AUTHOR]

Inner magnetospheric electrons are precipitated in the ionosphere via pitch‐angle (PA) scattering by lower band chorus (LBC), upper band chorus (UBC), and electrostatic electron cyclotron harmonic (ECH) waves. However, the PA scattering efficiency of low‐energy electrons (0.1–10 keV) has not been investigated via in situ observations because of difficulties in flux measurements within loss cones at the magnetosphere. In this study, we demonstrate that LBC, UBC, and ECH waves contribute to PA scattering of electrons at different energy ranges using the Arase (ERG) satellite observation data and successively detected the moderate loss cone filling, that is, approaching strong diffusion. Approaching strong diffusion by LBC, UBC, and ECH waves occurred at ∼2–20 keV, ∼1–10 keV, and ∼0.1–2 keV, respectively. The occurrence rate of the approaching strong diffusion by high‐amplitude LBC (>50 pT), UBC (>20 pT), and ECH (>10 mV/m) waves, respectively, reached ∼70%, ∼40%, and ∼30% higher than that without simultaneous wave activity. The energy range in which the occurrence rate was high agreed with the range where the PA diffusion rate of each wave exceeded the strong diffusion level based on the quasilinear theory. Key Points: The pitch‐angle scattering efficiencies by plasma waves are statistically investigated using in situ observationsLower band chorus waves caused approaching strong diffusion with the highest occurrence rate in the energy range of ∼2–20 keVElectrostatic electron cyclotron harmonic waves could contribute approaching strong diffusion in the ∼0.1–1 keV energy range [ABSTRACT FROM AUTHOR]

We present observations of an equatorward detachment of the auroral arc from the main oval and magnetically conjugate measurements made by the Arase satellite in the inner magnetosphere. The all‐sky imager at Gakona (magnetic latitude = 63.6°N), Alaska, shows the detachment of the auroral arc in both red and green lines at local midnight (∼0130–0230 MLT) on 30 March 2017. The electron density derived from the Arase in‐situ observations shows that this arc occurred outside the plasmapause. At the arc crossing, the electron flux of energies ∼0.1–2 keV is found to be locally enhanced at L∼4.3–4.5. We estimated auroral intensities for both red and green lines by using the Arase low‐energy (0.1–19 keV) electron flux data. The peak latitude of the estimated intensity shows reasonably good correspondence with the observed intensity mapped at the ionospheric footprints of the Arase satellite. These findings indicate that the observed arc detachment at Gakona was associated with the localized enhancement of low‐energy electrons (∼0.1–2 keV) at the inner edge of the electron plasma sheet. Further, we employ the simulation results of the Community Coordinated Modeling Center (CCMC), the BATS‐R‐US–CIMI 3‐D MHD code to understand the conditions in the inner magnetosphere around the time of detachment. Although the simulation could not reproduce the lower‐energy component responsible for the arc detachment, it successfully reproduced two earthward convection events at the lower radial distance (R) (R ≤ ∼4) around the time of arc detachment and the features of enhanced convection in similarity with the observations. Key Points: Conjugate measurements of an equatorward detachment of the auroral arc from the main oval and the Arase satellite in the inner magnetosphereEquatorward detachment of the auroral arc coincided with a localized enhancement of electrons of energies ∼0.1–2 keV deeper down to L∼4.3–4.5BATS‐R‐US–CIMI model successfully reproduced the enhancement of lower‐energy electrons (∼8–40 keV) at a lower radial distance (R < 4) [ABSTRACT FROM AUTHOR]

Medium‐scale traveling ionospheric disturbances (MSTIDs) are a phenomenon widely and frequently observed over the ionosphere from high to low latitudes. Night time MSTIDs are caused generally by the polarization electric field in the ionosphere. However, propagation of this polarization electric field to the magnetosphere has not yet been identified. Here, we report the first observation of the polarization electric field and associated density variations of a night time MSTID in the magnetosphere. The MSTID event was observed by an all‐sky airglow imager at Gakona (geographical latitude: 62.39°N, geographical longitude: 214.78°E, magnetic latitude: 63.20°N), Alaska. The Arase satellite passed over the MSTID in the inner magnetosphere at 0530–0800 UT (2030–2300 LT) on November 3, 2018. This MSTID, observed in 630 nm airglow images, was propagating westward with a horizontal wavelength of ∼165 km, a north–south phase front, and a phase velocity of ∼80 m/s. The Arase satellite footprint on the ionosphere crossed the MSTID in the direction nearly perpendicular to the MSTID phase fronts. The electric field and electron density observed by the Arase satellite showed periodic variation associated with the MSTID structure with amplitudes of ∼2 mV/m and ∼150 cm−3, respectively. The electric field variations projected to the ionosphere are mainly in the east‐west direction and are consistent with the direction of the polarization electric field expected from MSTID growth by E × B drift. This observation indicates that the polarization electric field associated with the MSTID in the ionosphere is projected onto the magnetosphere, causing plasma density fluctuations in the magnetosphere. Plain Language Summary: Medium‐scale traveling ionospheric disturbances (MSTIDs) are propagation of electron density fluctuation in the ionospheric F‐layer. MSTIDs are a common phenomenon from high to low latitudes. From simultaneous observations of airglow imagers in both hemispheres, MSTIDs are known to have a mirror structure at magnetic conjugate hemispheres. If an MSTID is generated by ionospheric instabilities, the polarization electric field associated with the MSTID should propagate along the magnetic field lines. In this paper, we report the first simultaneous observation of an MSTID using a ground‐based airglow imager and the Arase satellite in the magnetosphere. The electric field variations and plasma density fluctuations observed by Arase showed periodic variations associated with the MSTID structure. This result indicates that the spatial inhomogeneity of the ionospheric Pedersen conductivity associated with the MSTID yields the polarization electric field in the ionosphere, and that this polarization electric field was projected onto the magnetosphere. Key Points: First simultaneous observation of an medium‐scale traveling ionospheric disturbance (MSTID) using a ground‐based airglow imager and the Arase satellite in the magnetosphereThe polarization electric field associated with the MSTID in the ionosphere was projected to the magnetosphere and observed by AraseThe electric field and electron density observed by the Arase satellite showed a periodic variation associated with the MSTID structure [ABSTRACT FROM AUTHOR]

This study reports a relation between electron flux modulations and chorus emissions by using correlation analysis. On April 18, 2017, Arase observed an enhancement of electron fluxes and intensification of banded chorus emissions at the same time. A result of the analysis shows that both the upper‐band and lower‐band chorus emissions have good correlations with field‐aligned electron fluxes that satisfy their resonance conditions. This indicates simultaneous interactions with both the emission bands and electrons, resulting in electron pitch‐angle scattering toward the magnetic field direction. In addition, low‐energy electron fluxes in the perpendicular direction also show positive correlations with the chorus intensities, probably because the chorus emissions are modulated by a fluctuation of perpendicular low‐energy electron fluxes. Plain Language Summary: Scientists have believed that pulsating auroras in the polar regions originate in precipitating electrons that are caused by a wave‐particle interaction in the magnetosphere. Recent observational studies show direct evidence that chorus waves near the magnetic equator scatter local magnetospheric electrons, which are then streaming along the field line down to the ionosphere to generate aurora pulsation in response to modulation of the chorus emissions. Chorus waves usually have two distinct frequency bands, that is, upper band and lower band, but it had not been investigated that how two emission bands interact with electrons. In this study, we analyzed Arase satellite's observation data and identified good correlations between field‐aligned electron fluxes and intensities of the upper‐band and lower‐band emissions. This result indicates that pitch‐angle scattering of electrons takes place by both chorus emission bands simultaneously. Key Points: Arase observed intense banded chorus emissions near the magnetic equator simultaneously with an electron flux enhancementParallel electron fluxes show good correlations with intensities of both the upper‐band and the lower‐band chorus wavesThe positive correlation indicates pitch‐angle scattering of electrons by the chorus waves toward the magnetic field direction [ABSTRACT FROM AUTHOR]

This report describes electron beams observed at high latitudes in the magnetosphere by the Arase satellite. According to fine angular channel measurements, beam electrons are mainly flowing away from the Earth, and are well collimated to within a few degrees. A statistical study indicates that the beams are seen when Arase is located at Lm > ∼5, and more frequently as the magnetosphere becomes active. The field lines of the beam events are traced back to the typical auroral ovals. The statistical properties of the beams are consistent with the interpretation that ionospheric electrons are accelerated by a parallel electric field of an auroral potential structure and are streaming upward to the high latitude magnetosphere. Plain Language Summary: It is well accepted that discrete aurora is generated by precipitating electrons that are accelerated by an upward electric field. As a counterpart, a downward electric field exists in the vicinity of the upward electric field, accelerating ionospheric electrons upward to the magnetosphere. Such electron beams have been already reported by spacecraft observations in low altitudes and also in the magnetosphere. It is known that electron beams observed in the magnetosphere are collimated, but the pitch angle widths of the collimated beams have not been well resolved yet. In this report, we describe results of electron beam observations in the high latitude magnetosphere based on fine angular channel measurements of electrons by the Arase satellite. Key Points: Arase observes electron beams extremely collimated to within a few degrees in the high latitude magnetosphereElectron beams flow away from the Earth along the field lines connected to the auroral ovalsBeam electrons originate from a return current region of auroras in the ionosphere [ABSTRACT FROM AUTHOR]

Electrostatic electron cyclotron harmonic (ECH) waves are generally excited in the magnetic equator region, in the sector from nightside to dayside during geomagnetically active conditions, and cause the pitch angle scattering by cyclotron resonance. The scattered electrons precipitate into the Earth's atmosphere and cause auroral emission. However, there is no observational evidence that ECH waves actually scatter electrons into the loss cone in the magnetosphere. In this study, from simultaneous wave and particle observation data obtained by the Arase satellite equipped with a high‐pitch angular resolution electron analyzer, we present evidence that the ECH wave intensity near the magnetic equator is correlated with an electron flux inside the loss cone with an energy of about 5 keV. The simulation suggests that this electron flux contributes to the auroral emission at 557.7 nm with an intensity of about 200 R. Plain Language Summary: Wave‐particle interaction via electrostatic electron cyclotron harmonic (ECH) waves is a promising generation mechanism for precipitating electrons into Earth's atmosphere and producing diffuse auroras. However, there is no observational evidence that ECH waves scatter electrons to cause auroral emissions. In this study, based on observation data obtained by the Arase satellite equipped with a high‐angular resolution electron analyzer, we identified an event during which the ECH wave intensity near the magnetic equator was correlated with the electron flux that precipitated into the Earth's atmosphere. Our simulation suggests that this electron flux contributes to visible oxygen green‐line auroral emission. Key Points: We found an event that electron cyclotron harmonic wave intensity correlated with electron flux in a loss cone with ~5 keV energyThe pitch‐angle diffusion coefficient of 5 keV is larger than those of other energies when the electron temperature is 8 eV and the wave normal angle is 88.5°The electron flux correlated with the ECH wave intensity can cause 557.7 nm auroral emission with ~200 R intensity [ABSTRACT FROM AUTHOR]

Auroral arcs and diffuse auroras are common phenomena at high latitudes, though characteristics of their source plasma and fields have not been well understood. We report the first observation of fields and particles including their pitch‐angle distributions in the source region of auroral arcs and diffuse auroras, using data from the Arase satellite at L ~ 6.0–6.5. The auroral arcs appeared and expanded both poleward and equatorward at local midnight from ~0308 UT on 11 September 2018 at Nain (magnetic latitude: 66°), Canada, during the expansion phase of a substorm, while diffuse auroras covered the whole sky after 0348 UT. The top part of auroral arcs was characterized by purple/blue emissions. Bidirectional field‐aligned electrons with structured energy‐time spectra were observed in the source region of auroral arcs, while source electrons became isotropic and less structured in the diffuse auroral region afterwards. We suggest that structured bidirectional electrons at energies below a few keV were caused by upward field‐aligned potential differences (upward electric field along geomagnetic field) reaching high altitudes (~30,000 km) above Arase. The bidirectional electrons above a few keV were probably caused by Fermi acceleration associated with the observed field dipolarization. Strong electric‐field fluctuations and earthward Poynting flux were observed at the arc crossing and are probably also caused by the field dipolarization. The ions showed time‐pitch‐angle dispersion caused by mirror reflection. These results indicate a clear contrast between auroral arcs and diffuse auroras in terms of source plasma and fields and generation mechanisms of auroral arcs in the inner magnetosphere. Plain Language Summary: Auroral arcs or curtains are a familiar phenomenon seen at high latitudes, and aurora is also present in diffuse form. In near‐Earth space, plasmas and electric and magnetic fields are known to have interactions that cause the auroral phenomena, but a direct link between measurements in space and the corresponding auroras near the surface has been hard to make. The Arase satellite carries advanced plasma and field instruments allowing detailed study of conditions in space, so campaign observations were carried out at Nain, Canada, in September 2018, at a time when it was expected to be connected to the region by following magnetic field lines. Both discrete and diffuse auroras were observed from the ground, while in space electrons and ions were observed, whose characteristics changed depending on whether the spacecraft was lined up with discrete auroras, or later, with diffuse auroras. The auroras and particles changed with time due to a "substorm," which made the auroras brighten while making the particles more energetic. The observations suggest mechanisms by which the particles may be energized during substorms, with direct measurements in the source region. Key Points: This is the first observation of the source plasma features of auroral arcs and diffuse auroras in the inner magnetosphere by AraseUnique purple/blue auroral arcs appeared in association with an arrival of corotating interaction region (CIR) in the solar windDuring the arc crossing, field‐aligned electrons, time‐pitch‐angle dispersion of ions, and strong electric field variations were observed [ABSTRACT FROM AUTHOR]

In this article we present a method for the determination of the gate voltage versus surface potential (V[sub GS]-ψ[sub S]) relationship in thin-film transistors (TFTs), from low frequency capacitance-voltage (C-V) characteristics. This information is very important for device design, process characterization, and modeling of TFTs and provides the basis for extracting the gap density of states. The accuracy of the method is demonstrated by applying it to the analysis of C-V data generated by two-dimensional simulations. Its application to laser recrystallized polysilicon TFTs is presented. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In this article we present a method for the accurate determination of interface and bulk density of states (DOS) in thin-film transistors (TFTs), based on the combined analysis of transfer (I[sub D]-V[sub GS]) and capacitance-voltage characteristics. This analysis has achieved a number of results, eliminating sources of inaccuracies that are known to be present in other methods. A procedure for the determination of the electron and hole flatband conductances and bulk Fermi energy is demonstrated. A recursive procedure is employed to extract the bulk DOS directly from Poisson's equation. The advantages of this method are the greater immunity to noise from the original data, the use of the complete Fermi function (no 0 K approximation), and the applicability to thin active layers. This method yields the interface state density spectrum as well as the bulk DOS. This information is very important for device design, process characterization, and modeling of TFTs. © 2001! American Institute of Physics. [ABSTRACT FROM AUTHOR]

Super Dual Auroral Radar Network (SuperDARN) observations show that ionospheric flow fluctuations of millihertz or lower‐frequency range with horizontal velocities of a few hundred meters per second appeared in the subauroral to midlatitude region during a magnetic storm on 27 March 2017. A set of the radars have provided the first ever observations that the fluctuations propagate azimuthally both westward and eastward simultaneously, showing bifurcated phase propagation associated with substorm expansion. Concurrent observations near the conjugate site in the inner magnetosphere made by the Arase satellite provide evidence that multiple drifting clouds of electrons in the near‐Earth equatorial plane were associated with the electric field fluctuations propagating eastward in the ionosphere. We interpret this event in terms of mesoscale pressure gradients carried by drifting ring current electrons that distort field lines one after another as they drift through the inner magnetosphere, causing eastward propagating ionospheric electric field fluctuations. Plain Language Summary: Midlatitude ionospheric radars called SuperDARN observed azimuthally propagating fluctuations of ionospheric plasma flow in association with substorm expansion during a magnetic storm on 27 March 2017. The radar observations have shown for the first time that the flow fluctuations bifurcate toward eastward and westward simultaneously. The Arase satellite in the near‐conjugate site of the eastward propagating ionospheric flow fluctuations in the inner magnetosphere saw repeated flux enhancement of energetic electrons. The good satellite‐radar conjunction gives observational evidence that the eastward propagating ionospheric flow fluctuations are driven by eastward drifting pressure bumps of electrons injected into the inner magnetosphere upon substorm expansion. Key Points: This study shows the first ever comprehensive observation of azimuthal bifurcation of substorm‐associated ionospheric flow fluctuationsThe eastward propagating portion of the flow fluctuations can be mapped to electron pressure enhancements in the inner magnetosphereWe propose that multiple pressure bumps of drifting energetic electrons directly cause the observed ionospheric flow fluctuations [ABSTRACT FROM AUTHOR]

The 9977 package is a certified type B transportation packaging that was designed to transport radioactive materials with a decay heat load of up to 19 W. The packaging was recently modified to accommodate increased content heat load (up to 38 W) by employing an aluminium heat dissipating sleeve outside the containment vessel (CV), as well as an aluminium spacer inside the CV holding two 3013 containers. This paper provides highlights of thermal analyses of the modified 9977 package that were performed to evaluate its compliance with the 10 CFR 71 regulatory safety requirements. Parametric studies were also performed to examine effects of (i) surface properties, e.g. light absorptivity and emissivity, of the packaging; (ii) total decay heat loads, ranging from 18 to 38 W; and (iii) distribution of decay heat load inside the CV on the temperature of the Viton O-ring seal. The results of thermal analyses show that for the normal condition of transport with insolation, increasing absorptivity and decreasing emissivity increase the temperature of the O-ring; decreasing heat load decreases the temperature of the O-ring, whereas changing heat load distribution has little effect on the temperature of the O-ring. Likewise, changing the thermal conductivity of the spacer inside the CVhas little effect on the temperature of the O-ring. Briefly discussed is the possible extension of the annual maintenance interval of the 9977 package, based on previous work and the data obtained in the long-term leak performance tests conducted by the Savannah River National Laboratory. [ABSTRACT FROM AUTHOR]

Nuclear materials are placed in shielded, stainless steel packaging for storage or transport. These drum type packages often employ a layer of foam, honeycomb, wood or cement that is sandwiched between thin metal shells to provide impact and thermal protection during hypothetical accidents, as those prescribed in the Code of Federal Regulations (10 CFR 71·73). The present work discusses the modelling of the thermal degradation of polyurethane (PU) foam within an annular region during an 800°C fire. Measurements and analysis by Hobbs and Lemmon [M. L. Hobbs and G. H. Lemmon: 'Polyurethane foam response to fire in practical geometries', Polym. Degrad. Stab., 2004, 84, 183-197.] indicate that at elevated temperatures, PU foam exhibits a two-stage, endothermic degradation. The first stage produces a degraded solid and a combustible gas; the second stage reaction consumes the degraded solid and produces another combustible gas. As a result, during a prolonged fire, a gas filled void develops beside the outer metal shell and grows inward toward the inner shell and the containment vessel. As a result of the radial symmetry in the drum geometry, a one-dimensional finite difference model is constructed for the annular foam region. Heat flux is applied to the inner surface to model the decay heat of the containment vessel contents. Thermal radiation and convection boundary conditions with a specified environmental temperature are applied to the outer surface. The material and reaction rate properties determined by Hobbs and Lemmon are applied to the foam. The annular region temperature and composition are determined as functions of radius and time after the environmental conditions are changed from room temperature to those of an 800°C fire. The effects of surface to surface radiation between the package's outer skin and the undegraded foam and the reaction rate reduction due to material damage during the reaction are evaluated for fires lasting 20 h. The peak package liner temperature caused by a 30 min fire is predicted to be 129°C, well below the short term limit for containment vessel seal (377°C). [ABSTRACT FROM AUTHOR]

Rank-Ordered Multifractal Analysis (ROMA), a technique capable of deciphering the multifractal characteristics of intermittent fluctuations, was originally applied to the results of a magnetohydrodynamic (MHD) simulation. Application of ROMA to measured fluctuations in the auroral zone, due to the dominant physical effects changing from kinetic to MHD as the scale increases, requires an additional level of rank-ordering in order to divide the domain of scales into regimes. An algorithm for the additional step in this double rank-ordering technique is discussed, and is demonstrated in the application to the electric field fluctuations in the auroral zone as an example. As a result of the double rank-ordering, ROMA is able to take into account the nonlinear crossover behavior characterized by the multiple regimes of time scales by providing a scaling variable and a scaling function that are global to all the time scales. [ABSTRACT FROM AUTHOR]

Fc γRIIB are low-affinity immunoglobulin (Ig)G receptors that we previously demonstrated to negatively regulate IgE-induced mast cell activation when coaggregated with Fc ℇRI. Here, we engineered and characterized a bispecific reagent capable of coaggregating Fc γRIIB with Fc ℇRI on human mast cells and basophils. A bispecific antibody was constructed by chemically crosslinking one Fab’ fragment against human IgE and one Fab’ fragment against human Fc γRII. This molecule was used to coaggregate Fc ℇRI with Fc γRII on human mast cells and basophils sensitized with human IgE antibodies, and the effect of coaggregation was examined on mediator release upon challenge with specific antigen. When used under these conditions, this bispecific antibody not only failed to trigger the release of histamine by IgE-sensitized cells, but it also prevented specific antigen from triggering histamine release. Comparable inhibitions were observed with mast cells and basophils derived in vitro from cord blood cells and with peripheral blood basophils. The bispecific antibody described here is the prototype of similar molecules that could be used in new therapeutic approaches of allergic diseases based on the coaggregation of activating receptors, such as Fc ℇRI, with inhibitory receptors, such as Fc γRIIB, that are constitutively expressed by mast cells and basophils. [ABSTRACT FROM AUTHOR]

The cell cycle has been the object of extensive studies for the past years. A complex network of molecular interactions has been identified. In particular, a class of cell cycle inhibitory proteins has been identified but details of the molecular mechanism of their action have yet to be resolved. These inhibitors regulate the progression through G1 and the G1/S transition via the inhibition of the cyclin-dependent kinase (Cdk) activity. The potential function of these negative regulators as tumor suppressors provides new insights into the link between the cell cycle and oncogenesis. Kip1 is a potent inhibitor of Cdks. In quiescent cells Kip1 accumulates without an increase in mRNA or protein synthesis. We demonstrated that cell cycle regulation of Kip1 levels, both in normal and transformed human cells, occurs via the ubiquitin-proteasome pathway. In a crude in vitro system, Kip1 is ubiquitinated and degraded in an ATP dependent manner and inhibition or depletion of the proteasome blocks Kip1 degradation. Human Ubc2 and Ubc3, the homologs of yeast Rad6 and Cdc34 gene products respectively, are specifically involved in the ubiquitination of Kip1. Compared to proliferating cells, quiescent cells contain a far lower amount of Kip1 ubiquitinating activity. These results represent the first demonstration that the ubiquitin-proteasome pathway plays a role in the regulation of a cell cycle protein in human cells, namely the Cdk inhibitor Kip1. The specific proteolysis of Kip1 may be involved in the pathway of inactivation of Cdks. [ABSTRACT FROM AUTHOR]

It has been found by mass spectrometric studies that the so-called '1:1-adduct' formed by N-( nbutyl)maleimide and benzaldazine, is in fact a solid mixture of one part bis-imide L and one part benzaldazine. Bis-imide L is one of the three stereoisomeric products obtained by the addition of two mole of N-( n-butyl)malemide and one mole of benzaldazine. The three stereoisomeric bis-imides gave identical mass spectra. Mass spectra of bis-imide M and bis-imide M- d2 are discussed, and confirm the proposed structures of perhydroprazolo-pyrazole derivatives for these 1:2-adducts. [ABSTRACT FROM AUTHOR]

The mass spectra of some substituted 2-pyrazolines and a pyrazolidine are discussed. With the exception of III which favours McLafferty rearrangements prior to fragmentation, I, IV and V fragment to give isocyanate or isothiocyanate radicals and ions with structures corresponding to their heterocyclic molecular compounds. These results which can be explained in the light of the concept of charge localization at preferential sites, are in good agreement with the ionization potential studies on substituted ureas and thioureas.5 Other compounds show simple straight-forward fragmentations upon electron-impact. [ABSTRACT FROM AUTHOR]

Skeletal rearrangement processes of the general type \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm ABC}^{\mathop {\rm + }\limits_{\rm .} } {\rm } \to {\rm AC}^{\mathop {\rm + }\limits_{\rm .} } {\rm + B} $\end{document} in which HCN is eliminated and also bond-forming reactions involving intramolecular aromatic substitution occur in aromatic azines upon electron impact. In addition, hydrogen rearrangements can lead to abundant benzonitrile and benzalimine molecular ions and their substituted analogues. The abundant [M1] ions are predominantly formed by loss of the methine hydrogen preceded by complete scrambling of the aromatic and methine hydrogens. The similarities between the processes occurring in azines and those in anils, both in their normal bond cleavages and in some bond-forming reactions are emphasized. [ABSTRACT FROM AUTHOR]

An approach to the analysis of a spherical circular microstrip antenna which is applicable to a relatively thick substrate is presented. Based on the spectral-domain Green's function formulation, the effect of the dielectric substrate as well as the spherical ground are incorporated. Numerical results for the radiation resistance agree well with the results using the generalized transmission line model (GTLM), which is accurate for a thin dielectric substrate only. [ABSTRACT FROM AUTHOR]

In this study, we describe small‐scale density depletions of cold electrons associated with electrostatic electron cyclotron harmonic (ECH) waves observed by the ERG (Exploration of energization and Radiation in Geospace) spacecraft during a plasmapause crossing near the magnetic equator in the postmidnight sector. The total electron density was roughly 2 orders of magnitude larger than that of the hot electrons, indicating existence of a cold and dense electron population below ∼20 eV. The cold electron density profile showed small‐scale density depletion regions, in which the ECH emissions were intensified. Moreover, a flux enhancement of hot electrons in the perpendicular direction was also associated with the ECH emissions intensity. This relation suggests perpendicular energization of electrons by electric field oscillation of the ECH waves. Plain Language Summary: This study clarifies a relation of cold‐electron density irregularities and electron cyclotron harmonic (ECH) waves, both of which are frequently observed in the inner magnetosphere but their relation had not been clearly indicated by observations. We analyzed a plasmapause crossing event on 12 April 2017 observed by the ERG spacecraft and found that the plasmapause had small‐scale density depletions of cold electrons and ECH emissions were intensified inside the depletion regions. This suggests that an ECH emission intensity can be controlled by a background cold‐electron population. In addition, enhancements of hot‐electron fluxes in the direction perpendicular to the local magnetic field were also observed in response to the ECH emissions. This is probably due to perpendicular energization of cold electrons by the oscillating electric field of the ECH waves. The close relation between cold electrons and ECH emission intensification, shown in this analysis, gives indication of leakage of ionospheric cold electrons and its control of equatorial ECH waves just outside the plasmapause. Key Points: The ERG spacecraft observes density depletions associated with ECH waves during a plasmapause crossingThe ECH waves are intensified inside the density depletion regionsThe electric field of the ECH waves energizes electrons in the perpendicular directions [ABSTRACT FROM AUTHOR]

Focuses on the role of nitric oxide (NO) in maintaining gastric mucosal integrity which helps in the prevention of non-steroidal anti-inflammatory drug (NSAID)-induced gastric damage. Approaches to NO administration against the gastric toxicity of NSAID; Administration of S-nitrosoglutathione in combination with high dose of piroxicam; Synthesis of NSAID with NO-donating moiety.