Tracking the formation and full evolution of polar cap ionization patches in the polar ionosphere, we directly observe the full Dungey convection cycle for southward interplanetary magnetic field ...(IMF) conditions. This enables us to study how the Dungey cycle influences the patches' evolution. The patches were initially segmented from the dayside storm enhanced density plume at the equatorward edge of the cusp, by the expansion and contraction of the polar cap boundary due to pulsed dayside magnetopause reconnection, as indicated by in situ Time History of Events and Macroscale Interactions during Substorms (THEMIS) observations. Convection led to the patches entering the polar cap and being transported antisunward, while being continuously monitored by the globally distributed arrays of GPS receivers and Super Dual Auroral Radar Network radars. Changes in convection over time resulted in the patches following a range of trajectories, each of which differed somewhat from the classical twin‐cell convection streamlines. Pulsed nightside reconnection, occurring as part of the magnetospheric substorm cycle, modulated the exit of the patches from the polar cap, as confirmed by coordinated observations of the magnetometer at Tromsø and European Incoherent Scatter Tromsø UHF radar. After exiting the polar cap, the patches broke up into a number of plasma blobs and returned sunward in the auroral return flow of the dawn and/or dusk convection cell. The full circulation time was about 3 h.
Key Points
Direct observations of the full Dungey cycle by tracking polar cap patches
Formation and evolution of patches modulated by dayside and nightside reconnections
The full circulation time was about 3 h
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Two types of poleward moving plasma concentration enhancements (PMPCEs) were observed during a sequence of pulsed reconnection events, both in the morning convection cell: Type L (low density) was ...associated with a cusp flow channel and seems likely to have been produced by ionization associated with particle precipitation, while Type H (high density) appeared to originate from the segmentation of the tongue of ionization by the processes which produced the Type L events. As a result, the Type L and Type H PMPCEs were interspersed, producing a complex density structure which underlines the importance of cusp flow channels as a mechanism for segmenting and structuring electron density in the cusp and shows the necessity of differentiating between at least two classes of electron density patches.
Key Points
First observed TOI patches in the morning cell
Differentiating between at least two classes of electron density patches
TOI patches segmented by flow channels with precipitation electrons
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
A comparison tool has been developed by mapping the global GPS total electron content (TEC) and large coverage of ionospheric scintillations together on the geomagnetic latitude/magnetic local time ...coordinates. Using this tool, a comparison between large‐scale ionospheric irregularities and scintillations is pursued during a geomagnetic storm. Irregularities, such as storm enhanced density, middle‐latitude trough, and polar cap patches, are clearly identified from the TEC maps. At the edges of these irregularities, clear scintillations appeared but their behaviors were different. Phase scintillations (σφ) were almost always larger than amplitude scintillations (S4) at the edges of these irregularities, associated with bursty flows or flow reversals with large density gradients. An unexpected scintillation feature appeared inside the modeled auroral oval where S4 were much larger than σφ, most likely caused by particle precipitations around the exiting polar cap patches.
Key Points
A comparison tool has been developed by mapping global GPS TEC and large coverage of scintillations together on MLAT/MLT coordinates
σφ were larger than S4 at the edges of the irregularities associated with bursty flows or flow reversals with large density gradients
S4 were much larger than σφ in the auroral oval, most likely caused by particle precipitations around the exiting polar cap patches
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
We have used all‐sky imaging to relate different types of auroral oval disturbances to large‐scale traveling ionospheric disturbances (LSTIDs). We selected eight nights with good all‐sky imaging and ...Global Positioning System total electron content coverage, including five non–storm time periods with isolated initiations of geomagnetic activity and three storm main phase periods with continuous activity. Periods with LSTIDs generally started and stopped with initiation and cessation of activity. We found evidence that individual LSTIDs often show 1‐1 correspondence with identifiable auroral disturbances, disturbances either being related to a substorm onset or to auroral streamers without a substorm. Since substorm ground magnetic depressions are directly related to the electric fields and electron precipitation of auroral streamers, we hypothesize that streamers may be the primary drivers of individual nightside LSTIDs with or without a substorm. Additionally, we found evidence that (1) LSTIDs detection is more likely near the longitude range of the initiating disturbance than further away, (2) the orientation of LSTID phase fronts depends on location relative to disturbance longitude, and (3) disturbance ionospheric current and magnetic latitude may influence whether a given disturbance leads to a detectable LSTID. Numerous LSTIDs (10 to 12 over 7‐ to 8‐hr periods) were detected during southward interplanetary magnetic field periods of coronal mass ejection storm main phases, the vast majority reflecting streamers in the absence of substorms. Less LSTIDs were seen during the one examined high‐speed‐stream storm. We have also found evidence that omega band disturbances may drive interesting TIDs that are distinct from the LSTIDs driven by the substorm and streamer disturbances.
Key Points
All‐sky imaging was used to relate auroral oval disturbances to large‐scale traveling ionospheric disturbances (LSTIDs)
Streamers may be the primary drivers of individual nightside LSTIDs, with or without a substorm
Possible LSTID longitude, orientation, and strength connections suggested
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Summary
The aim of the current study was to use a Bayesian network meta-analysis to evaluate the relative benefits and risks of balloon kyphoplasty (BK), percutaneous vertebroplasty (PVP), and ...non-surgical treatment (NST) for patients with osteoporotic vertebral compression fractures (OVCFs). The results demonstrate that for pain and functional status, PVP was significantly better than NST, while the three treatments did not significantly differ in other outcomes.
Introduction
BK, PVP, and NST are widely used to treat OVCFs, but preferable treatment is unknown. The aim of the current study was to use a Bayesian network meta-analysis to evaluate the relative benefits and risks of BK, PVP, and NST for patients with OVCFs.
Methods
PubMed, EMBASE, and the Cochrane Library were screened. Based on the preplanned eligibility criteria, we screened and included randomized controlled trials that compared BK, PVP, and NST in treating patients with OVCFs. The risk of bias for individual studies was appraised. The data were pooled using a Bayesian network meta-analysis and a traditional direct comparison meta-analysis.
Results
Of the 1057 relevant studies, 15 were eligible and included. Compared with NST, PVP significantly reduced pain, Oswestry Disability Index (ODI), and Roland–Morris Disability Questionnaire (RMDQ). The comparative efficacy of BK and PVP was similar for pain (mean difference (MD) 0.51, 95% credible interval (CrI) − 0.35 to 1.4), ODI (MD 0.11, 95% CrI − 13 to 13), and RMDQ (MD 1.2, 95% CrI − 2.7 to 5.4). The European Quality of Life–5 Dimensions (EQ–5D) and Physical Component Summary subscales of the Medical Outcomes Study 36-Item Short-Form General Health Survey (SF-36 PCS) did not differ significantly. There were also no substantial differences in the risks of subsequent vertebral fractures, adjacent vertebral fractures, and re-fractures at the treated level across all comparators. The results of pairwise meta-analyses were almost consistent with those of network meta-analyses. The treatment ranking indicated that PVP had the highest probability of being the most effective for pain, ODI, RMDQ, and EQ-5D. BK had the highest probability of improving SF-36 PCS and of reducing the risk of subsequent vertebral fractures and re-fractures at the treated level. NST was ranked first in preventing adjacent vertebral fractures.
Conclusion
PVP was the most effective method for improving pain, functional status, and quality of life (based on EQ-5D). BK emerged as the best intervention for decreasing the risk of subsequent vertebral fractures and re-fractures at the treated level. NST could be ranked first in reducing adjacent vertebral fractures. The future directions of OVCFs treatment will depend on the outcomes of additional and larger randomized trials in comparing BK with PVP.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Reconfigurable devices offer the ability to program electronic circuits on demand. In this work, we demonstrated on-demand creation of artificial neurons, synapses, and memory capacitors in ...post-fabricated perovskite NdNiO
devices that can be simply reconfigured for a specific purpose by single-shot electric pulses. The sensitivity of electronic properties of perovskite nickelates to the local distribution of hydrogen ions enabled these results. With experimental data from our memory capacitors, simulation results of a reservoir computing framework showed excellent performance for tasks such as digit recognition and classification of electrocardiogram heartbeat activity. Using our reconfigurable artificial neurons and synapses, simulated dynamic networks outperformed static networks for incremental learning scenarios. The ability to fashion the building blocks of brain-inspired computers on demand opens up new directions in adaptive networks.
The strongest Southern Hemisphere minor sudden stratospheric warming (SSW) in the last 40 years occurred in September 2019 and resulted in unprecedented weakening of the stratospheric polar vortex. ...Ionospheric total electron content (TEC) observations are used to provide an overview of statistically significant anomalies in the low‐latitude ionosphere during this event. Quasi‐semidiurnal perturbations of TEC are observed in response to the SSW, similar to those seen during Northern Hemisphere SSWs. Analysis indicates the existence of quasi‐periodic oscillations in TEC in the crests of the equatorial ionization anomaly, with strong 5‐ to 6‐day and 2‐ to 3‐day periodicities. Ionospheric anomalies from the combined effects of multiple mechanisms exceed a factor of 2, comparable to the strongest anomalies associated with Northern Hemisphere SSWs. These results also indicate a remarkable longitudinal variation in the character and magnitude of variations that could be related to a modulation of the non‐migrating diurnal tide.
Plain Language Summary
Sudden stratospheric warming, a large‐scale meteorological disturbance, has been associated with profound anomalies in the Earth atmosphere, from troposphere all the way to the upper thermosphere and ionosphere. During the last decade, numerous studies showed that Arctic sudden stratospheric warmings cause especially large anomalies in the low‐latitude ionosphere. However, it was not clear if similar ionospheric anomalies can be produced by Antarctic sudden stratospheric warming, mostly because Antarctic sudden stratospheric warmings are pretty rare. In this study, we provide an overview of ionospheric anomalies in total electron content observed in September 2019, when very strong sudden stratospheric warming developed over Antarctica. We conclude that Antarctic events produce even more dynamical changes in the ionosphere than Arctic events. We report for the first time large differences in the observed features at locations that are separated by only 30° in longitude. Our results indicate that stratospheric weather can strongly influence the state of the ionosphere not only during December–February period (winter in the Northern Hemisphere), but also during September (equinox conditions).
Key Points
Minor Antarctic sudden stratospheric warming of September 2019 produces large ionospheric anomalies at low latitudes
Changes of total electron content exceeding a factor of 2 are observed
Large longitudinal differences in total electron content response to Antarctic SSW are reported
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Given the important role of nitrogen input from livestock systems in terrestrial nutrient cycles and the atmospheric chemical composition, it is vital to have a robust estimation of the magnitude and ...spatiotemporal variation in manure nitrogen production and its application to cropland across the globe. In this study, we used the dataset from the Global Livestock Impact Mapping System (GLIMS) in conjunction with country-specific annual livestock populations to reconstruct the manure nitrogen production during 1860–2014. The estimated manure nitrogen production increased from 21.4 Tg N yr−1 in 1860 to 131.0 Tg N yr−1 in 2014 with a significant annual increasing trend (0.7 Tg N yr−1, p < 0.01). Changes in manure nitrogen production exhibited high spatial variability and concentrated in several hotspots (e.g., Western Europe, India, northeastern China, and southeastern Australia) across the globe over the study period. In the 1860s, the northern midlatitude region was the largest manure producer, accounting for ∼ 52 % of the global total, while low-latitude regions became the largest share (∼ 48 %) in the most recent 5 years (2010–2014). Among all the continents, Asia accounted for over one-fourth of the global manure production during 1860–2014. Cattle dominated the manure nitrogen production and contributed ∼ 44 % of the total manure nitrogen production in 2014, followed by goats, sheep, swine, and chickens. The manure nitrogen application to cropland accounts for less than one-fifth of the total manure nitrogen production over the study period. The 5 arcmin gridded global dataset of manure nitrogen production generated from this study could be used as an input for global or regional land surface and ecosystem models to evaluate the impacts of manure nitrogen on key biogeochemical processes and water quality. To ensure food security and environmental sustainability, it is necessary to implement proper manure management practices on cropland across the globe. Datasets are available at https://doi.org/10.1594/PANGAEA.871980 (Zhang et al., 2017).
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
We present results from an analysis of all data taken by the BICEP2, Keck Array, and BICEP3 CMB polarization experiments up to and including the 2018 observing season. We add additional Keck Array ...observations at 220 GHz and BICEP3 observations at 95 GHz to the previous 95 / 150 / 220 GHz dataset. The Q / U maps now reach depths of 2.8, 2.8, and 8.8 μ KCMB arcmin at 95, 150, and 220 GHz, respectively, over an effective area of ≈ 600 square degrees at 95 GHz and ≈ 400 square degrees at 150 and 220 GHz. The 220 GHz maps now achieve a signal-to-noise ratio on polarized dust emission exceeding that of Planck at 353 GHz. We take auto- and cross-spectra between these maps and publicly available WMAP and Planck maps at frequencies from 23 to 353 GHz and evaluate the joint likelihood of the spectra versus a multicomponent model of lensed Λ CDM + r + dust + synchrotron + noise . The foreground model has seven parameters, and no longer requires a prior on the frequency spectral index of the dust emission taken from measurements on other regions of the sky. This model is an adequate description of the data at the current noise levels. The likelihood analysis yields the constraint r0.05 < 0.036 at 95% confidence. Running maximum likelihood search on simulations we obtain unbiased results and find that σ ( r ) = 0.009 . These are the strongest constraints to date on primordial gravitational waves.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UL, UM
Epidermal growth factor receptor (EGFR) mutations typically occur in exons 18-21 and are established driver mutations in non-small cell lung cancer (NSCLC)
. Targeted therapies are approved for ...patients with 'classical' mutations and a small number of other mutations
. However, effective therapies have not been identified for additional EGFR mutations. Furthermore, the frequency and effects of atypical EGFR mutations on drug sensitivity are unknown
. Here we characterize the mutational landscape in 16,715 patients with EGFR-mutant NSCLC, and establish the structure-function relationship of EGFR mutations on drug sensitivity. We found that EGFR mutations can be separated into four distinct subgroups on the basis of sensitivity and structural changes that retrospectively predict patient outcomes following treatment with EGFR inhibitors better than traditional exon-based groups. Together, these data delineate a structure-based approach for defining functional groups of EGFR mutations that can effectively guide treatment and clinical trial choices for patients with EGFR-mutant NSCLC and suggest that a structure-function-based approach may improve the prediction of drug sensitivity to targeted therapies in oncogenes with diverse mutations.
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GEOZS, IJS, IMTLJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK, ZAGLJ
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