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Several studies have compared the molecular responses between e14a2 and e13a2 BCR::ABL1 transcripts in chronic myeloid leukemia (CML) patients treated with front-line imatinib, but there were very limited studies on nilotinib or dasatinib-treated patients. We retrospectively analyzed the molecular responses in 1124 CML patients with the e14a2 or e13a2 transcript receiving front-line imatinib, nilotinib or dasatinib treatment. Patients with the e14a2 transcript had higher optimal response rates than those with the e13a2 transcript at 12 months in the imatinib-treated group, and 6 and 12 months in the nilotinib-treated group. The optimal response rates were not significantly different between the two transcripts in the dasatinib-treated group at landmark molecular responses. With a median follow-up time of 48.4 months, higher cumulative incidences of BCR::ABL1 International Scale ≤1% and major molecular response were observed in patients with the e14a2 rather than the e13a2 transcript receiving front-line imatinib or nilotinib treatment, but not in dasatinib-treated patients. The progression-free survival and overall survival did not differ between the two transcripts in all three treatment groups. In view of the speed and depth of molecular responses, BCR::ABL1 transcript subtypes might provide helpful information in selecting a front-line tyrosine kinase inhibitor for individual young patients with future potential treatment-free remission.

With lowering costs of sequencing and genetic profiling techniques, genetic drivers can now be detected readily in tumors but current prognostic models for Natural-killer/T cell lymphoma (NKTCL) have yet to fully leverage on them for prognosticating patients. Here, we used next-generation sequencing to sequence 260 NKTCL tumors, and trained a genomic prognostic model (GPM) with the genomic mutations and survival data from this retrospective cohort of patients using LASSO Cox regression. The GPM is defined by the mutational status of 13 prognostic genes and is weakly correlated with the risk-features in International Prognostic Index (IPI), Prognostic Index for Natural-Killer cell lymphoma (PINK), and PINK-Epstein-Barr virus (PINK-E). Cox-proportional hazard multivariate regression also showed that the new GPM is independent and significant for both progression-free survival (PFS, HR: 3.73, 95% CI 2.07-6.73; p

Objectives Early mortality, defined as death within 120 days after initiated antitumor therapy, is an important issue especially for elder patients with B-cell lymphoma. This study aimed to evaluate the clinical value of comprehensive geriatric assessment (CGA) in early mortality prediction in elderly patients with B-cell lymphoma receiving immunochemotherapy. Methods Seventy-six consecutive patients with newly diagnosed B-cell lymphoma receiving immunochemotherapy from a medical center in Taiwan were prospectively enrolled. Patients were divided into fit (n = 49) and frail (n = 27) groups per pretreatment CGA for early mortality comparison. Results The early mortality rate in our patient cohort was 16% (n = 12): from 6% in patients with no CGA domain impairment to 43% in patients with ≥4 CGA domain impairment. The early mortality rate was 6% and 33% in fit and frail patients (odds ratio, 7.67; 95% CI, 1.86-31.6; P = .005), respectively. Frailty was the significant predictor for early mortality in univariate and multivariate analysis. Conclusion In this study, the number of geriatric domain impairment is positively associated with the early mortality risk in elderly patients with B-cell lymphoma. Therefore, CGA can help clinicians to identify the risk of early mortality in elderly patients and provide alternative treatment.

The Air Force Research Laboratory’s (AFRL) Demonstration and Science Experiments (DSX) spacecraft was launched on June 25, 2019. Although DSX flight operations were recently completed on May 31, 20...

This study presents results from magnetic field line conjunctions between the medium-Earth orbiting Demonstration and Science Experiments (DSX) satellite and the low-Earth orbiting VLF Propagation ...

Background. Anemia and pancytopenia are not uncommon in patients with chronic kidney disease (CKD). Nevertheless, there is insufficient literature analyzing bone marrow pathology in patients with CKD or end-stage kidney disease (ESKD) receiving dialysis. Methods. This observational cohort study included 22 patients with ESKD and 23 patients with CKD that received bone marrow biopsy and aspiration at Chang Gung Memorial Hospital. Demographic, hematological, and biochemical data were collected at the time of bone marrow study for analysis. Results. Bone marrow aspiration demonstrated that patients with ESKD had a lower percentage of blasts than patients with CKD (0.52 ± 0.84 versus 1.06 ± 0.78 %, p = 0.033). Bone marrow biopsy revealed that the overall incidence of hypocellular bone marrow was 55.6%. Furthermore, patients with ESKD had higher proportion of hypocellular bone marrow than patients with CKD (72.7% versus 39.1%, p = 0.023). In a multivariate logistic regression model, it was revealed that ESKD status (odds ratio 9.43, 95% confidence interval 1.66–53.63, p = 0.011) and megakaryocyte count within bone marrow (odds ratio 0.48, 95% confidence interval 0.29–0.79, p = 0.004) were significant predictors for bone marrow hypocellularity. Conclusion. Bone marrow hypocellularity is common in patients with kidney dysfunction. Hypocellular marrow occurs more frequently in patients with ESKD than patients with CKD.

Frailty is a common clinical syndrome among the elderly; however, it is frequently neglected in patients with hematological malignancies, especially among the Asian population. This study is aimed to evaluate the prevalence and effect of frailty on survival outcomes in elderly Asian patients with B-cell lymphoma.We prospectively enrolled 76 consecutive patients with age ≥ 65 years and newly diagnosed B-cell lymphoma and were receiving immunochemotherapy in a medical center in Taiwan between August 2016 and December 2017. The frailty of all patients was assessed using a comprehensive geriatric assessment (CGA) within 7 days before immunochemotherapy.Twenty-seven patients (36%) were allocated to the frail group based on CGA. With a median follow-up duration of 26.5 (range, 1.7-39.8) months, the 1- and 2-year survival rates were 68% and 58%, respectively, for all group of patients. In patients in the non-frail group, the 1-year and 2-year survival rates were 81% and 71%, respectively, compared to 44% and 33%, respectively, in the frail group (hazard ratio [HR], 3.57, 95% confidence interval [CI], 1.74-7.30; p = 0.001). Age ≥ 75years (adjusted HR 2.57, 95% CI 1.02-6.47, p = 0.045), presence of B-symptoms (adjusted HR 2.43, 95% CI 1.05-5.60, p = 0.038), and frailty (adjusted HR 3.03, 95% CI 1.29-7.11, p = 0.011) were independent prognostic factors in the multivariate analysis.Frailty significantly influenced the survival outcome as an independent prognostic factor in elderly patients with B-cell lymphoma undergoing immunochemotherapy. Pretreatment frailty assessment is critical to assist clinicians and patients with B-cell lymphoma with prognosis prediction and counseling on an appropriate treatment goal.

International audience; Energetic electrons have occasionally been observed with high intensity in the low-latitude quasi-trapping region, below the inner radiation belt, where their intensity is normally low. During magnetic storms in November 2004 and July 2006, electrons reached magnetic drift shells with L

This paper describes version 1.5 of the AE9/AP9 family of space radiation climatology models. The most significant update is the inclusion of new data sets that change the flux maps. These new data include measurements from Van Allen Probes, Azur, and the HiLET sensor on the TWINS-2 spacecraft. In recognition of international contributions to the models, we introduce the IRENE nomenclature for International Radiation Environment Near Earth.

Background: Ropeginterferon alpha-2b (Ropeg) is a novel pegylated interferon-alpha approved for the treatment of polycythemia vera (PV) in Europe and Taiwan. Prior to its approval in Taiwan, the major options for patients with myeloproliferative neoplasms (MPNs) included hydroxyurea (HU) and/or anagrelide. Patients who are HU/anagrelide resistant/intolerant have limited options, as ruxolitinib is not subsidized by the national health insurance in Taiwan for PV. In 2017, the manufacturer provided a compassionate use program (CUP) for patients who were HU and/or anagrelide resistant/intolerant. Herein, we assessed the efficacy and safety of Ropeg in 20 MPN patients. Methods: To be eligible, patients must be resistant or intolerant to currently available therapies for MPN in Taiwan, mainly HU and anagrelide. Patients with autoimmune disorders, psychiatric illness, and acute/chronic infections were excluded. An accelerated dosing regimen was used, starting from 250 µg, and increased by 100 µg every two weeks until it reached the target dose of 500 µg, if no self-reported discomforts or abnormalities in biochemical or hematological profiles were observed. Efficacy assessments included hematologic parameters, phlebotomy need, and JAK2V617F allele burden. Hematologic remission was defined as platelets ≤400 x 10^9/L and white blood cells Results: A total of 20 patients received treatment, which included 14 PV, 4 ET, 1 post-ET myelofibrosis (MF), and 1 pre-fibrotic primary MF (Table 1). There were 12 female and 8 male patients with a median age of 56.1 years old. Of these 20 patients, 18 had JAK2V617F mutation and 5 had a history of thrombosis. Of the 18 ET and PV patients, 13 achieved hematologic remission. The ET patients seemed to achieve hematologic remission faster than PV patients (19.3 vs. 33.2 weeks). Of the 18 patients with JAK2V617F mutation, 7 PV patients and 1 post-ET MF patient achieved molecular response, which took a median of 46 weeks after Ropeg treatment. Reduction in JAK2V617F allele burden was observed in 12 patients. One MF patient discontinued treatment due to disease progression. Another PV patient discontinued treatment due to acute myeloid leukemia transformation, although after treatment, the patient returned to PV state and continued Ropeg treatment. Overall, the drug was well tolerated, as most of the treatment-related adverse events (AEs) were mild to moderate. The AE profile was consistent with those from the phase 3 PROUD/CONTI-PV study. There were no unbearable side effects that led to treatment discontinuation. Conclusion: Our study provided evidence in the efficacy and safety of Ropeg for the treatment of HU-/anagrelide-resistant/intolerant MPNs. Hematologic remission was observed in ET and PV patients, whereas molecular response was observed in only PV patients, possibly due to the small sample size of ET patients. Our experience with Ropeg suggests it to be a promising option for the treatment of MPNs with drug-resistance/intolerance. Figure 1 Figure 1. Disclosures Chen: PharmaEssentia: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Amgen, Celgene, Novartis, and Panco Healthcare: Honoraria. Shih: PharmaEssentia Co: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene Ltd: Research Funding; Ltd: Research Funding; Novartis: Research Funding. OffLabel Disclosure: Ropeginterferon alfa-2b is a novel interferon alpha indicated for the treatment of polycythemia vera in Europe and in Taiwan. This abstract describes the use of this agent for the treatment of myeloproliferative neoplasm patients with hydroxyurea/anagrelide resistance/intolerance.

Previous studies have demonstrated that energy can enter the high-latitude regions of the Ionosphere-Thermosphere (IT) system on open field lines. To assess the extent of high-latitude energy input, we have carried out a study of Poynting flux measured by the Defense Meteorological Satellite Program (DMSP) satellites during magnetic storms. We report sporadic intense Poynting fluxes measured by four DMSP satellites at polar latitudes during two moderate magnetic storms which occurred in August and September 2011. Comparisons with a widely used empirical model for energy input to the IT system show that the model does not adequately capture electromagnetic (EM) energy at very high latitudes during storms. We have extended this study to include more than 30 storm events and find that intense EM energy is frequently detected poleward of 75° magnetic latitude.

BACKGROUND Owing to the shortage of hematopoietic stem cells from matched sibling donors (MSD) and matched unrelated donors (MUD), the number of patients undergoing haploidentical allogeneic hematopoietic stem cell transplantation (allo-HSCT) has rapidly increased. Despite a comparable overall survival (OS) and leukemia-free survival using this approach, some evidence suggests that haploidentical allo-HSCT recipients have a higher incidence of cytomegalovirus (CMV) infection, though this has not been clearly established. METHODS This study retrospectively compared the cumulative incidence of CMV DNAemia, 2-year OS, and leukemia-free survival rates in acute leukemia patients with MSD (n = 41), MUD (n = 18), and haploidentical donor allografts (n = 21). RESULTS The cumulative incidences of CMV DNAemia at day 180 in the MSD, MUD, and haploidentical groups were 39.0, 55.6, and 85.7%, respectively (P

A 2-dimensional bounce-averaged test particle code was developed to examine trapped electron trajectories during geomagnetic storms with the assumption of conservation of the first and second adiabatic invariants. The March 2013 storm was selected as an example because the geomagnetic activity KP index sharply increased from 2+ to 7- at 6:00UT on March 17. Electron measurements with energies between 37 and 460 keV from the Magnetic Electron Ion Spectrometer (MagEIS) instrument onboard Van Allen Probes (VAP) are used as initial conditions prior to the storm onset, and served to validate test particle simulations during the storm. Simulation results help to interpret the observed electron injection as non-diffusive radial transport over a short distance in the inner belt and slot region based on various electric field models, although the quantitative comparisons are not precise. We show that electron drift trajectories are sensitive to the selection of electric field models. Moreover, our simulation results suggest that the actual field strength of penetration electric fields during this storm is stronger than any existing electric field model, particularly for L ≤ 2.

Electron measurements from the MagEIS instruments on Van Allen Probes, for kinetic energies ∼100 to 400 keV, show characteristic dynamical features of the innermost ( L≲1.3) radiation belt: rapid injections, slow decay, and structured energy spectra. There are also periods of steady or slowly increasing intensity and of fast decay following injections. Local time asymmetry, with higher intensity near dawn, is interpreted as evidence for drift shell distortion by a convection electric field of magnitude ∼0.4 mV/m during geomagnetically quiet times. Fast fluctuations in the electric field, on the drift time scale, cause inward diffusion. Assuming they are proportional to changes in Kp, the resulting diffusion coefficient is sufficient to replenish trapped electrons lost by atmospheric scattering. Major electric field increases cause injections by inward electron transport. An injection associated with the June 2015 magnetic storm is consistent with an enhanced field magnitude ∼5 mV/m. Subsequent drift echoes cause spectral structure.

In this study, we report observations and simulation results of heated neutrals at various altitudes inside the polar cap during two magnetic storms in January 2005. The Poynting flux measurements from the Defense Meteorological Satellite Program (DMSP) satellites show enhanced energy input in the polar cap during the storm main phase, which is underestimated in the TIE-GCM simulation. Neutral temperature measurements at 250 km from the ground-based Fabry-Perot Interferometer (FPI) at Resolute Bay are presented, along with the neutral density observations at 360 km and 470 km from Challenging Minisatellite Payload (CHAMP) and the Gravity Recovery and Climate Experiment (GRACE) satellites, respectively. These data have been analyzed to demonstrate the altitudinal dependence of neutral response to the storm energy input. By comparing the TIE-GCM simulation results and the observations, we demonstrate that Poynting fluxes as well as the thermosphere response were underestimated in the model. The simulated neutral temperature at Resolute Bay increases by approximately 260° and 280° K for the two events, respectively, much lower than the observed temperature enhancements of 750° and 900° K. Neutral density enhancements with more than 30% increase over the background density were also observed at polar latitudes, with no clear distinction between the auroral zone and polar cap. All measurements indicate enhancements at high latitudes poleward of 80° magnetic latitude (MLAT) implying that substantial heating can occur within the polar cap during storms.

Objectives We aimed to define the clinical features, outcome, and prognostic factors for extranodal NK/T-cell lymphoma (ENKTL) patients in Taiwan. Methods We retrospectively reviewed 101 ENKTL patients diagnosed between February 1998 and October 2015. Results The median age of 101 patients was 52 years old (range 22-85); 76.2% of patients were Ann Arbor stage I/II disease. The 5-year progression-free survival (PFS) and overall survival (OS) were 49.9% and 54.8%, respectively. Patients with log[EBV-DNA] ≥ 3.8 and bone marrow hemophagocytosis at diagnosis had inferior PFS and OS. Most stage I/II patients received combined chemoradiotherapy with anthracycline-containing regimen, with overall response rate of 96.7%, complete response rate 86.9%, 5-year PFS 65%, and OS 72%. The relapse rate was 29.3% with a short median disease-free survival of 6.2 months. In advanced stage patients, overall response rate was only 13.6%, with median PFS 2.3 months, and OS 4.8 months. Age ≥ 60 (HR 3.773, 95% CI 1.733-8.215, P = 0.001) and stage III/IV (HR 7.785, 95% CI 2.312-26.213, P = 0.001) were unfavorable prognostic factors for PFS and OS by multivariate analyses. Conclusions Age ≥ 60 and stage III/IV are independent poor prognostic factors for PFS and OS. Early-stage ENKTL patients had good response to combined chemoradiotherapy with anthracycline-containing regimen but with a high relapse rate and short disease-free survival. Anthracycline-containing regimen in advanced stage had poor response and dismal outcome.

We examine the response of the thermosphere to the impact of solar wind dynamic pressure enhancements using observations and global magneto-hydrodynamics (MHD) simulations by the OpenGGCM model. Combining neutral density observations from the Challenging Minisatellite Payload (CHAMP) and the Gravity Recovery and Climate Experiment (GRACE) satellites with simultaneous Poynting flux measurements from the Defense Meteorological Satellite Program (DMSP) F16, we find that thermospheric density as well as downward Poynting flux intensified shortly after a sudden enhancement of the solar wind dynamic pressure. The intensification manifested mostly on the dayside high-latitude region with peak intensity in the vicinity of the noon and prenoon cusp. OpenGGCM modeling results show that the ionospheric Joule heating increased abruptly in response to the sudden enhancement of the dynamic pressure in the same region as the observed Poynting flux and neutral density enhancements. The modeling results show that the enhanced Joule heating coincides, both in time and location, with the appearance of a pair of high-latitude localized field-aligned currents (FACs) in the cusp region. The FACs intensified and extended azimuthally. Coincidental with the solar wind dynamic pressure enhancement, the y component of the interplanetary magnetic field (IMF) By became strongly positive and, in addition, had some large fluctuations. We explore the separate and combined effects of the dynamic pressure and IMF By perturbations, with specifically designed simulation experiments that isolate the effect of each solar wind parameter. We find that the dynamic pressure enhancement is the primary source for the Joule heating and neutral density enhancements, but the IMF By modulates the level of enhancement.

Recent studies have reported that thermospheric effects due to solar wind driving can be observed poleward of auroral latitudes. In these papers, the measured neutral mass density perturbations appear as narrow, localized maxima in the cusp and polar cap. They conclude that Joule heating below the spacecraft is the cause of the mass density increases, which are sometimes associated with local field-aligned current structures, but not always. In this paper we investigate neutral mass densities measured by accelerometers on the CHAllenging Minisatellite Payload (CHAMP) and Gravity Recovery and Climate Experiment (GRACE) spacecraft from launch until years 2010 (CHAMP) and 2012 (GRACE), approximately 10 years of observations from each satellite. We extract local maxima in neutral mass densities over the background using a smoothing window with size of one quarter of the orbit. The maxima have been analyzed for each year and also for the duration of each set of satellite observations. We show where they occur, under what solar wind conditions, and their relation to magnetic activity. The region with the highest frequency of occurrence coincides approximately with the cusp and mantle, with little direct evidence of an auroral zone source. Our conclusions agree with the “hot polar cap” observations that have been reported and studied in the past.

The parameterizations of monoenergetic particle impact ionization in Fang et al. (2010) (Fang2010) and Fang et al. (2013) (Fang2013) are applied to the complex energy spectra measured by DMSP F16 satellite to calculate the ionization rates from electron and ion precipitations for a Northern Hemisphere pass from 0030 UT to 0106 UT on 6 August 2011. Clear enhancement of electron flux is found in the polar cap. The mean electron energy in the polar cap is mostly above 100 eV, while the mean energy in the auroral zone is typically above 1 keV. At the same time, F16 captures a strong Poynting flux enhancement in the polar cap, which is comparable to those in the auroral zone. The particle impact ionization rates using Fang2010 and Fang2013 parameterizations show clear enhancement at F region altitudes mainly due to the low-energy precipitating electrons, peaking probably in the cusp but also showing enhanced levels throughout most of the polar cap region. The general circulation models (GCMs), National Center for Atmospheric Research Thermosphere-Ionosphere-Electrodynamics General Circulation Model, and Global Ionosphere-Thermosphere Model, using their default empirical formulations of particle impact ionization, do not capture the observed features shown in the total particle ionization rate applying the Fang2010 and Fang2013 parameterizations to DMSP measurements. The difference between GCM simulations and Fang2010 and Fang2013 applied to DMSP data is due to the difference of both the inputs to the models and the parameterization of the ionization rates.

We present results from an analysis of high-latitude ionosphere-thermosphere (IT) coupling to the solar wind during a moderate magnetic storm which occurred on 5–6 August 2011. During the storm, a multipoint set of observations of the ionosphere and thermosphere was available. We make use of ionospheric measurements of electromagnetic and particle energy made by the Defense Meteorological Satellite Program and neutral densities measured by the Gravity Recovery and Climate Experiment satellite to infer (1) the energy budget and (2) timing of the energy transfer process during the storm. We conclude that the primary location for energy input to the IT system may be the extremely high latitude region. We suggest that the total energy available to the IT system is not completely captured either by observation or empirical models.

[1] Wavelets are a time-domain method that is able to extract both time and frequency information from a signal. The Morlet wavelet is used here to characterize the magnitude of ionospheric irregularities using measurements of the total ion density from the Coupled Ion Neutral Dynamics Investigation package onboard the Communications/Navigation Outage Forecasting System spacecraft. The power in ionospheric irregularities at scale sizes less than 128 km is used to generate an irregularity amplitude index. This index is used with a phase screen analysis to form an estimate of scintillation at the satellite location. The temporal information retained in a wavelet analysis also allows for an accurate power spectrum calculation even when used on short segments of data which is useful for real-time processing of irregularity detection onboard a satellite or for analyzing the long data sets produced by a satellite. To validate the process, a comparison of the in situ scintillation estimate and Scintillation Network and Decision Aid measurements of the S4 index is presented.

The radiation belts and plasma in the Earth’s magnetosphere pose hazards to satellite systems which restrict design and orbit options with a resultant impact on mission performance and cost. For decades the standard space environment specification used for spacecraft design has been provided by the NASA AE8 and AP8 trapped radiation belt models. There are well-known limitations on their performance, however, and the need for a new trapped radiation and plasma model has been recognized by the engineering community for some time. To address this challenge a new set of models, denoted AE9/AP9/SPM, for energetic electrons, energetic protons and space plasma has been developed. The new models offer significant improvements including more detailed spatial resolution and the quantification of uncertainty due to both space weather and instrument errors. Fundamental to the model design, construction and operation are a number of new data sets and a novel statistical approach which captures first order temporal and spatial correlations allowing for the Monte-Carlo estimation of flux thresholds for user-specified percentile levels (e.g., 50th and 95th) over the course of the mission. An overview of the model architecture, data reduction methods, statistics algorithms, user application and initial validation is presented in this paper.

The electromagnetic interaction between Jupiter and Io has been studied extensively since the discovery of Io-controlled decametric radio emissions (DAMs). A variety of mechanisms for electromagnetic disturbances have been considered including a unipolar inductor, the excitation of large-amplitude Alfvén waves, the generation of electrostatic electric fields parallel to the ambient magnetic field, and etc. Recently, three auroral acceleration regions categorized by terrestrial physicists have been applied to the Jupiter-Io coupling system: the Alfvénic acceleration region is associated with bright emissions at Io's magnetic footprint, whereas the quasi-static system of anti-planetward and planetward currents set up at the inner and outer edges of the torus in the downstream region of Io's wake. This review paper summarizes the current understanding of the coupling mechanisms between Jupiter's ionosphere and the Io plasma torus, as well as the electron acceleration mechanism necessary to excite Io-associated emissions.

Observations have revealed large Poynting flux and soft electron precipitation around the cusp region, which have strong impacts on the polar ionosphere/thermosphere. Simulations also confirmed that Poynting flux and soft electron precipitation significantly change the neutral density and dynamics around the dayside polar cap boundary regions. However, no detailed study has been conducted to show if they should coincide with each other or not. Our analysis of Defense Meteorological Satellite Program (DMSP) satellite data reveals a complex correlation between them. Poynting flux and soft particle precipitation are coincident in some cases (match cases), but a clear displacement between them can also be identified in others (nonmatch cases). In the 29 cusp crossings from F13 we investigated, the ratio between nonmatch and match cases is close to 1:4. In nonmatch cases, the displacement between the Poynting flux enhancement and soft particle precipitation enhancement can be as large as 1° in geomagnetic latitude., Key Points Correlation of Poynting flux and particle precipitationRelative location of two energy inputs in the dayside polar cap boundaryInfluence from the IMF conditions

Artificial Ionospheric Modification (AIM) can occur through deliberate or incidental injections of aerosols, chemicals or radio (RF) signals into the ionosphere. The Metal Oxide Space Clouds (MOSC) experiment was undertaken in April/May 2013 to investigate chemical AIM. Two sounding rockets were launched from Kwajalein Atoll and each released a cloud of vaporized samarium (Sm). The samarium created a localized plasma cloud that formed an additional ionospheric layer. The effects were measured by a wide range of ground based instrumentation; this included a 17 channel direction finding chirp receiver. This system detected the new layer which remained visible to the HF sounder for approximately 25 minutes. The layer's maximum usable frequency peaked at approximately 10 MHz immediately after release. The direction to the reflection point remained constant at 355° whilst the new layer was visible to the sounder.

We apply a recently developed dynamic fluid-kinetic (DyFK) model to simulate and investigate the effects of soft auroral electron precipitation and perpendicular ion heating by waves on the plasma outflow along auroral field lines. The DyFK model is constructed by coupling a fluid ionospheric model for the region from 120 to 800 km to a semikinetic treatment for topside through several RE altitude region. This approach, which is described in detail here, allows a partially self-consistent description of the plasma transport along high-latitude flux tubes where both low-altitude ionospheric heating and ionization production and loss as well as high-altitude energization and kinetic effects are incorporated and stressed. In the present work, we investigate the combined effects of the F region plasma production and electron heating by soft auroral electron precipitation and ion perpendicular wave heating at high altitudes, which produces ion conies. The auroral event simulated here involves 1.5 hours of moderate soft electron precipitation and relatively weak ion cyclotron waves along the magnetic field lines. The simulations reveal the F region electron heating and ionization by the soft electron precipitation, driving a topside O+ upflow of up to 109 cm−2 s−1 below 1000 km within 30 min after the electron precipitation is turned on. The enhanced O+ upflow plumes would be still gravitationally bound in the absence of further energization at higher altitudes. However, the synergistic effects of the increased upwelling ion supply driven by the precipitation and the wave-driven ion heating at higher altitudes combine to enhance O+ bulk outflow by an order of magnitude above the baseline polar wind level to a net outflow flux of 108 ions cm−2 s−1 with a density of 10 ions cm−3 and bulk velocity of 12 km s−1 at 3 RE altitude. Various O+ conic velocity distributions develop within 10 min after transverse heating is initiated, and their characteristic energies saturate at approximately 10 eV for the peak wave-induced heating rates of 10−14 ergs s−1 at 2 RE here. H+ is also affected by the increases of O+ due to H+–O+ collisional drag in the 1000 – 4000 km altitude transition region. H+ flow is much less affected by the wave heating because of the faster transit times through the high-altitude wave heating zone and the lower H+ perpendicular heating rates which were incorporated here. The H+ bulk flow consists of a flux of 108 ions cm−2 s−1, a density of 4 ions cm−3, and a velocity of 30 km s−1 at 3 RE altitude.

An ionospheric plasma fluid transport model is used to investigate the effects of soft (

In February 1996, the POLAR spacecraft was placed in an elliptical orbit with a 9 R E geocentric distance apogee in the northern hemisphere and 1.8 R E perigee in the southern hemisphere. The Thermal Ion Dynamics Experiment (TIDE) on POLAR has allowed sampling of the three-dimensional ion distribution functions with excellent energy, angular, and mass resolution. The Plasma Source Instrument (PSI), when operated, allows sufficient diminution of the electric potential to observe the polar wind at very high altitudes. In this paper, we describe the results of a survey of the polar wind characteristics for H + , He + , and O + as observed by TIDE at ∼5000 km and ∼8 R E altitudes over the polar cap during April-May 1996. At 5000 km altitude, the H + polar wind exhibits a supersonic outflow, while O + shows subsonic downflow, which suggests a cleft ion fountain origin for the O + ions in the polar cap region. Dramatic decreases of the 5000 km altitude H + and O + ion densities and fluxes are seen as the solar zenith angle increases from 90° to 100° for the ionospheric base, which is consistent with solar illumination ionization control. However, the polar cap downward O + flow and density decline from dayside to nightside in magnetic coordinates suggest a cleft ion fountain origin for the polar cap O + . Cleft ion fountain origin O + density plumes could also be partially responsible for a similar day-night asymmetry in H + , owing to the charge-exchange reaction. At 8 R E altitude, both H + and O + outflows are supersonic and H + is the highly dominant ion species. The average bulk ion field-aligned velocities are in the typical ratio V O+ : V He+ : V H+ ∼ 2: 3: 5, which may suggest a tendency toward comparable energy gains, such as via an electric potential layer.

It has long been recognized that photoelectrons can enhance the ambipolar electric fields affecting polar wind outflows [e.g., Axford, 1968; Lemaire, 1972]. Since ionospheric ions and electrons are produced in large part by photoionization of the neutral atmosphere at lower altitudes, and the maximum photoelectron production rate occurs in the 130–140 km altitude range, it is essential to model this photoelectron-driven polar wind self-consistently from the E region to an altitude of several Earth radii. Here we describe a new steady state coupled fluid-semikinetic model to efficiently couple the source region to the high-altitude regions. This model couples a fluid treatment for the 120–800 km altitude range, a generalized semikinetic (GSK) treatment for the altitude range 800 km to 2 RE, and a steady state collisionless semikinetic method for the altitude range 2–9 RE. We apply this model to investigate the photoelectron-driven polar wind with ionospheric conditions ranging from solar minimum (F10.7 = 90) to solar maximum (F10.7 = 200). The O+ and H+ densities are found to increase by factors of approximately 5 and 2, respectively, from solar minimum to solar maximum below 3 RE altitude. However, the parallel bulk velocities display little variation with increased F10.7 for altitudes below 3 RE. An electric potential layer of the order of 40 V develops above 3 RE altitude, when the included downward magnetosheath electron fluxes (such as polar rain) are insufficient to balance the ionospheric photoelectron flux. Such potential layers accelerate the ionospheric ions to supersonic speeds at high altitudes, above 3 RE, but not at low altitudes. We also found that the potential layer decreases from 40 to 8.5 V for solar minimum conditions and from 46 to 12 V for solar maximum conditions when the magnetospheric electron density is increased from 0.05 to 2 cm−3.

During magnetic storms, there is a strong response in the ionosphere and thermosphere which occurs at polar latitudes. Energy input in the form of Poynting flux and energetic particle precipitation, and energy output in the form of heated ions and neutrals have been detected at different altitudes and all local times. We have analyzed a number of storms, using satellite data from the Defense Meteorological Satellite Program (DMSP), the Gravity Recovery and Climate Experiment (GRACE), Gravity field and steady-state Ocean Circulation Explorer (GOCE), and Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) mission. Poynting flux measured by instruments on four DMSP spacecraft during storms which occurred in 2011–2012 was observed in both hemispheres to peak at both auroral and polar latitudes. By contrast, the measured ion temperatures at DMSP and maxima in neutral density at GOCE and GRACE altitudes maximize in the polar region most frequently with little evidence of Joule heating at auroral latitudes at these spacecraft orbital locations.

[1] The electron decay timescale (τ) is well known to be associated with radiation belt loss processes. Knowledge of τ is important for understanding pitch angle and radial diffusion mechanisms. Previous studies reported decay timescales from the inner belt to geosynchronous orbits; however, relatively few statistical studies have been focused on the region beyond the traditional outer belt. In this paper, a systematic calculation of electron decay times at 5 1 day. τ is examined as a function of energy, pitch angle, L shell, Kp, and AE during magnetically disturbed periods when Dst ≤ −50 nT. Results show that τ increases with increasing electron energy at L 6.6. This suggests radial transport as the dominant effect at L > 6.6. Additionally, τ decreases with increasing L-shell. This dependence has the strongest correlation and is seen in all energies and pitch angles. However,τ has no systematic dependence with pitch angle suggesting that pitch angle diffusion also plays a key role in the electron loss process. Based on our results, τ can be expressed as a function of energy and L, and coefficients are provided for a two-variable fit. Surprisingly,τ is slightly longer for higher activity cases at L < 6.6, which is inconsistent with the current radial or pitch angle diffusion models. Global effective decay times on the timescale of days place an upper bound on the true loss timescale.

[1] The Communications/Navigation Outage Forecasting System (C/NOFS) satellite observed large-scale density depletions at postmidnight and early morning local times in the Northern Hemisphere summer during solar minimum conditions. Using electric field data obtained from the vector electric field instrument (VEFI) as input, the assimilative physics-based model (PBMOD) qualitatively reproduced more than 70% of the large-scale density depletions observed by the Planar Langmuir Probe (PLP) onboard C/NOFS. In contrast, the use of a climatological specification of plasma drifts in the model produces no plasma depletions at night. Results from a one-month statistical study, we found that the large-scale depletion structures most often occur near longitudes of 60°, 140°, and 330°, suggesting that these depletions may be associated with nonmigrating atmospheric tides, although the generation mechanisms of eastward electric fields at postmidnight local times are still uncertain. In this paper, densities obtained from both assimilation and climatology for the entire month of June 2008 are compared with PLP data from C/NOFS and the Challenging Minisatellite Payload (CHAMP), as well as special sensor ionospheric plasma drift/scintillation meter (SSIES) measurements from the Defense Meteorological Satellite Program (DMSP) satellites. Our statistical study has shown that, on average, the densities obtained by the PBMOD when it assimilates VEFI electric fields agree better with observed background densities than when PBMOD uses climatological electric fields.