bluuebunny/crossref_metadata_2025_split huggingface dataset:
Statistical Study of Phase Relationship Between Magnetic and Plasma Pressures in the Near‐Earth Nightside Magnetosphere Using the THEMIS‐E Satellite
Authors: Nishi Katsuki , Shiokawa Kazuo , Glassmeier Karl‐Heinz , Mieth Johannes Z. D. 
Published: November 2018

AbstractDistributions of plasma and magnetic pressures are the basic information to investigate macroscopic dynamics of the Earth's magnetosphere. Several studies have been made on magnetic and plasma pressures and macroscopic plasma instabilities in the magnetosphere. However, correlation between magnetic and plasma pressure variations has not been statistically investigated. In this paper, we analyze the statistical characteristics of the phase relationships between variations of magnetic and plasma pressures at frequencies of 4–15 mHz using 2 years of the THEMIS‐E satellite data in the nightside magnetosphere. Spectral peaks with coherence greater than 0.85 between magnetic and plasma pressures for 1‐hr time segments were selected. The average occurrence rates of the phase relationships are antiphase (within ±10∘ from 180°), 39.75%; in‐phase (within ±10∘ from 0°), 0.73%; and other phases (10–170°), 49.83%. For the other‐phase events, the phase differences are much closer to antiphase rather than to in‐phase. Thus, we conclude that the two pressure variations tend to be antiphase. The antiphase and in‐phase relationships are observed mainly at radial distances outside 8 RE and inside 8 RE, respectively. The high occurrence region of antiphase relationship is in the dawnside during magnetically quiet times and shifts to dusk side at active times defined as Dst <−10 nT. The occurrence rates of the phase relationships do not change significantly depending on the AE and Dst indices, plasma β, and IMF‐Bz. Based on these results, we discuss the correspondence between the phase relationships and the possible magnetohydrodynamic force balances that can produce these phase relationships.
Magnetosphere‐Ionosphere Connection of Storm‐Time Region‐2 Field‐Aligned Current and Ring Current: Arase and AMPERE Observations
Authors: Imajo S. , Nosé M. , Matsuoka A. , Kasahara S. , Yokota S. , Teramoto M. , Keika K. , Motoba T. , Anderson B. , Nomura R. , Fujimoto A. , Shinohara I. , Miyoshi Y. 
Published: November 2018

AbstractStorm‐time region‐2 field‐aligned currents (R2 FACs) are believed to be connected between the ring current region and the ionosphere, but this connection has not been clarified by simultaneous in situ observations. We confirmed the connection of upward R2 FACs during 16 July and 18 June 2017 storm events using coordinated magnetic observations by the Arase satellite in medium‐Earth orbit and the Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE). The upward FACs were determined by drastic changes in the azimuthal magnetic field at Arase in the off‐equatorial (3‐ to 4‐RE radial distance and 1–2 RE above the magnetic equator) postmidnight inner magnetosphere. The magnetic latitude of the FAC observed by Arase projected onto the ionosphere was consistent with that of the ionospheric FAC observed by the AMPERE. Using the conservation of the ratio between the current density and the total magnetic field along the field line, we showed that the current between Arase and AMPERE was almost conserved, meaning that a large portion of the R2 FAC was generated in the low‐latitude inner magnetosphere. We also calculated the plasma pressures of H+ and O+ ions and pressure‐driven currents to examine their relationship for the first event. The O+ pressure contributed significantly to the inner part of the total azimuthal current. The peaks of combined pressure of H+ and O+, and pressure‐driven currents were located inside and outside the FAC, respectively. A simple model calculation indicated that this spatial relationship is controlled by the day‐night asymmetry of magnetic field.
Pore‐Scale Modeling of Spontaneous Imbibition Behavior in a Complex Shale Porous Structure by Pseudopotential Lattice Boltzmann Method
Authors: Zheng Jiangtao , Ju Yang , Wang Moran 
Published: November 2018

AbstractSpontaneous imbibition of fracturing fluid into shale matrix is one of the primary reasons for the low flowback rate in shale gas wells after the hydraulic fracturing. This leads to concerns of impacts on both environment and shale gas production. A direct pore‐scale simulation is crucial to gain a deep understanding of spontaneous imbibition behavior and its impacts. The porous structures in the shale matrix are characterized by not only a geometrical complexity but also a mixed wettability, which bring great challenges to simulation methods. An improved pseudo‐potential lattice Boltzmann method is proposed to simulate the spontaneous imbibition behavior in a reproduced three‐dimensional porous structure of shale. The results show that the nanoscale hydrophilic pores provide the driving force and a storage place for the residual treatment fluid. The pore size and wettability heterogeneity lead to the nonuniform menisci propagation and fracturing fluid distribution in the model. Specifically, the fracturing fluid imbibed quicker in the larger pores at the early stage and gradually migrated into the smaller pores during the process. With a limited volume of the fracturing fluid, a portion of the larger pores was finally reopened. The analysis of saturation and apparent gas permeability data during the spontaneous imbibition process showed a great recovery of the model permeability along with the reopened pores. These results provide direct evidence of the residual fracturing fluid migration pattern in the shale reservoir and its influence on shale gas production.
Observations of Air‐Sea Momentum Flux Variability Across the Inner Shelf
Authors: Ortiz‐Suslow David G. , Haus Brian K. , Williams Neil J. , Graber Hans C. , MacMahan Jamie H. 
Published: November 2018

AbstractOver the open ocean, the aerodynamic drag coefficient is typically well predicted; however, the impact depth‐limited processes have on the drag remains underexplored. A case study is presented here where winds, waves, and currents were simultaneously observed from a mobile platform that repeatedly transected the inner shelf of Monterey Bay, CA. Eddy covariance‐derived drag coefficients were compared to several bulk parameterizations, including all of the roughness variations of COARE 3.5 and two explicitly depth‐limited models. The analysis demonstrated that the drag was underestimated by O(2–4) times and the variability with wind speed or cross‐shore distance was not well predicted. The drag based on a recent depth‐limited roughness length model performed substantially better than the rest of the bulk estimates, which were all within 15% of each other and effectively equivalent given typical operational uncertainties. The measured friction velocity was compared to a wave‐dependent parameterization and generalizing the model to arbitrary water depth significantly improved the mean observation‐model difference to within 30%. Latent variability in the observation‐model comparison was associated with stability, wind direction, and wave steepness. The wind stress angle variability was also analyzed. Stress veering was correlated with the alongshore surface current within 2 km from shore (r2= 0.7–0.95, p < 0.05); offshore of this margin, consistent wind stress veering was observed and may be attributable to a secondary, low‐frequency swell system. These results demonstrate that it remains a persistent challenge to accurately predict wind stress variability in the nearshore, especially at locations with complex wave and current fields.
Estimating Source Region Influences on Black Carbon Abundance, Microphysics, and Radiative Effect Observed Over South Korea
Authors: Lamb Kara D. , Perring Anne E. , Samset Bjørn , Peterson Dave , Davis Sean , Anderson Bruce E. , Beyersdorf Andreas , Blake Donald R. , Campuzano‐Jost Pedro , Corr Chelsea A. , Diskin Glenn S. , Kondo Yutaka , Moteki Nobuhiro , Nault Benjamin A. , Oh Jun , Park Minsu , Pusede Sally E. , Simpson Isobel J. , Thornhill Kenneth L. , Wisthaler Armin , Schwarz Joshua P. 
Published: November 2018

AbstractEast Asia is the strongest global source region for anthropogenic black carbon (BC), the most important light‐absorbing aerosol contributing to direct radiative climate forcing. To provide extended observational constraints on regional BC distributions and impacts, in situ measurements of BC were obtained with a single particle soot photometer during the May/June 2016 Korean‐United States Air Quality aircraft campaign (KORUS‐AQ) in South Korea. Unique chemical tracer relationships were associated with BC sourced from different regions. The extent and variability in vertical BC mass burden for 48 profiles over a single site near Seoul were investigated using back trajectory and chemical tracer analysis. Meteorologically driven changes in transport influenced the relative importance of different source regions, impacting observed BC loadings at all altitudes. Internal mixing and size distributions of BC further demonstrated dependence on source region: BC attributed to China had a larger mass median diameter (180 ± 13 nm) than BC attributed to South Korea (152 ± 25 nm), and BC associated with long‐range transport was less thickly coated (60 ± 4 nm) than that sourced from South Korea (75 ± 16 nm). The column BC direct radiative effect at the top of the atmosphere was estimated to be
W/m2, with average values for different meteorological periods varying by a factor of 2 due to changes in the BC vertical profile. During the campaign, BC sourced from South Korea (≤ 31%), China (22%), and Russia (14%) were the most significant single‐region contributors to the column direct radiative effect.
Stress Field Evolution of the Southernmost Andean Cordillera From Paleostress Analysis (Argentine Tierra del Fuego)
Authors: Maestro A. , Ruano P. , Torres Carbonell P. , Bohoyo F. , Galindo‐Zaldívar J. , Pedrera A. , Ruiz‐Constán A. , González‐Castillo L. , Ibarra P. , López‐Martínez J. 
Published: November 2018

AbstractThe Argentine Tierra del Fuego comprises part of the roughly east‐west trending southern end of the Andean Cordillera intensely deformed since the Mesozoic. Mesostructures have been measured in Late Jurassic to Miocene rocks. Taking into account statistical criteria to provide a representative stress tensor from a fault population, this study defines 28 paleostress tensors pertaining to 22 sites. The orientation of σ1 shows two main modes trending E‐W to ESE‐WNW and NE‐SW. In addition, extensional sites reveal N‐S, NE‐SW, ESE‐WNW, and NW‐SE horizontal σ3 and vertical σ1. The stress fields obtained are congruous with a regional NE‐SW compressive stress direction active in the study zone since the Late Cretaceous. Shortening was coeval with a 30° counterclockwise rotation of the Patagonian orogenic curve and the indentation of the orogenic wedge against a basement high, the Río Chico Arch, up to the early Miocene. The indentation caused a modification in the orientation of the compressive stress trajectories, showing NE‐SW direction in Sorondo Range sector and NW‐SE in Mitre Peninsula area. Since the late Miocene, left‐lateral activity along the Magallanes‐Fagnano Fault System produced local deviations of the NE‐SW compressive stress toward an E‐W direction. The present‐day stress field is also characterized by NE‐SW subhorizontal P axis derived from earthquake focal mechanisms and geodetic studies.
The Spanish‐Portuguese Central System: An Example of Intense Intraplate Deformation and Strain Partitioning
Authors: de Vicente G. , Cunha P. P. , Muñoz‐Martín A. , Cloetingh S. A. P. L. , Olaiz A. , Vegas R. 
Published: November 2018

AbstractThe intraplate deformation of Iberia during the Cenozoic produced a series of ranges and deformation belts with a wide variety of structural trends. The Spanish‐Portuguese Central System is the most prominent feature crossing over the whole of central Iberia. It is a large thick‐skinned crustal pop‐up with NE‐SW to E‐W thrusts. However, the 500‐km‐long left‐lateral strike‐slip Messejana‐Plasencia fault, also NE‐SW oriented, bends these thrusts to produce NE‐SW local paleostresses close to the fault, which seems to be consistent with a common deformational arrangement. This is also supported by the similar sedimentary infilling characteristics found in the surrounding Cenozoic basins. The moment of the maximum intraplate deformation is registered at the same time in all these basins during the upper Priabonian‐lower Chattian. As there are two possible sources for the intraplate compressive stresses, the Pyrenean (N‐S shortening) orogen to the north and the Betic (NW‐SE shortening) orogen to the south, neither can simply explain both simultaneous movements (NE‐SW strike‐slip and NE‐SW thrusting). The deduced age of the main deformation indicates a Pyrenean origin. In contrast, the concept of strain partitioning between the two types of faults gives as a result an overall north trending compression. Existing data do not support crustal detachment from the Betics neither from the Pyrenees but are consistent with a crustal uplift related to lithospheric folding. The subsequent Betic‐related stress field only slightly reworked previously Pyrenean‐related structures, except for the Portuguese sector, where tectonic activity occurred mainly in the Upper Miocene.
Raindrop Size and Flow Depth Control Sediment Sorting in Shallow Flows on Steep Slopes
Authors: Wang L. , Fang N. F. , Yue Z. J. , Shi Z. H. , Hua L. 
Published: November 2018

AbstractRaindrop size and flow depth interactions determine the energy available for erosion processes. A detailed laboratory study was conducted to investigate the influence of raindrop size on sediment sorting in shallow flows on steep slopes. Raindrops with sizes of 1.34, 2.45, and 4.04 mm were applied to three inflows (0.65, 1, and 2 L/min) with the same rainfall intensity (90 mm/hr). The De Brouckere mean diameter (D[4,3]) was enhanced with increases in the ratio between flow depth and raindrop size (h/d; p < 0.05), indicating that more raindrop energy dissipated in deeper flows. Moreover, a greater proportion of energy was dissipated from small raindrops than from large ones with an increasing flow depth. Particles >0.5 mm were slightly enriched by rolling under 1.34‐mm raindrop impact, whereas enrichment did not occur under 2.45‐ and 4.04‐mm raindrop impact, probably because the latter induced more severe aggregate disintegration, resulting in fewer coarse particles. The mean sediment concentrations under inflows of 0.65, 1, and 2 L/min were 101.65, 89.32, and 79.02 g/L, respectively. Shallow flows on steep slopes effectively carried detached particles; moreover, coarse particles could roll along the slopes, which was inconsistent with their behavior on gentle slopes. This study highlights the need to understand the influence of the interaction between raindrop size and flow depth on erosion processes associated with sediment size selectivity for better erosion modeling and water quality prediction.
Elevated allostatic load early in the course of schizophrenia
Authors: Savransky Anya , Chiappelli Joshua , Fisseha Feven , Wisner Krista M. , Xiaoming Du , Mirmomen S. Milad , Jones Aaron D. , Adhikari Bhim M. , Bruce Heather A. , Rowland Laura M. , Hong L. Elliot 
Published: November 2018

AbstractStress plays a significant role in schizophrenia from disease onset to exacerbation of psychotic symptoms. Allostatic load (AL) is a measure of cumulative stress to the organism. This study is an extension of our previous work on AL and its relationship to brain structures. Here, we further determined whether elevated AL is a function of illness chronicity, or if it is already present early in the course of schizophrenia. AL was compared in schizophrenia patients early in the illness (within 5 years of disease onset), patients with chronic schizophrenia (more than 5 years of illness), and two groups of healthy controls that were age-and sex-matched to the two patient groups. This work is presented with an expanded sample and includes about two-thirds of the participants who were previously reported. We found that patients with early psychosis had significantly elevated AL score compared with their age-matched controls (p = 0.005). Chronic course patients also had elevated AL compared with age-matched controls (p = 0.003). Immune and stress hormone AL subcomponents were nominally higher in early-stage patients compared with controls (p = 0.005 and 0.04, respectively). Greater AL was also associated with more severe positive psychotic symptoms in early-stage patients (r = 0.54, p = 0.01). Elevated levels of allostatic load are already present in the early years of the schizophrenia illness, particularly in patients with more severe psychotic symptoms. AL may be a useful evaluation for the need of early intervention on psychosomatic comorbidity.
Electron aspirator using electron–electron scattering in nanoscale silicon
Authors: Firdaus Himma , Watanabe Tokinobu , Hori Masahiro , Moraru Daniel , Takahashi Yasuo , Fujiwara Akira , Ono Yukinori 
Published: November 2018

AbstractCurrent enhancement without increasing the input power is a critical issue to be pursued for electronic circuits. However, drivability of metal-oxide-semiconductor (MOS) transistors is limited by the source-injection current, and electrons that have passed through the source unavoidably waste their momentum to the phonon bath. Here, we propose the Si electron-aspirator, a nanometer-scaled MOS device with a T-shaped branch, to go beyond this limit. The device utilizes the hydrodynamic nature of electrons due to the electron–electron scattering, by which the injected hot electrons transfer their momentum to cold electrons before they relax with the phonon bath. This momentum transfer induces an electron flow from the grounded side terminal without additional power sources. The operation is demonstrated by observing the output-current enhancement by a factor of about 3 at 8 K, which reveals that the electron–electron scattering can govern the electron transport in nanometer-scaled MOS devices, and increase their effective drivability.
Mechanistic insights of enhanced spin polaron conduction in CuO through atomic doping
Authors: Smart Tyler J. , Cardiel Allison C. , Wu Feng , Choi Kyoung-Shin , Ping Yuan 
Published: November 2018

AbstractThe formation of a “spin polaron” stems from strong spin-charge-lattice interactions in magnetic oxides, which leads to a localization of carriers accompanied by local magnetic polarization and lattice distortion. For example, cupric oxide (CuO), which is a promising photocathode material and shares important similarities with high Tc superconductors, conducts holes through spin polaron hopping with flipped spins at Cu atoms where a spin polaron has formed. The formation of these spin polarons results in an activated hopping conduction process where the carriers must not only overcome strong electron−phonon coupling but also strong magnetic coupling. Collectively, these effects cause low carrier conduction in CuO and hinder its applications. To overcome this fundamental limitation, we demonstrate from first-principles calculations how doping can improve hopping conduction through simultaneous improvement of hole concentration and hopping mobility in magnetic oxides such as CuO. Specifically, using Li doping as an example, we show that Li has a low ionization energy that improves hole concentration, and lowers the hopping barrier through both the electron−phonon and magnetic couplings' reduction that improves hopping mobility. Finally, this improved conduction predicted by theory is validated through the synthesis of Li-doped CuO electrodes which show enhanced photocurrent compared to pristine CuO electrodes. We conclude that doping with nonmagnetic shallow impurities is an effective strategy to improve hopping conductivities in magnetic oxides.
Risk factors of levodopa-induced dyskinesia in Parkinson’s disease: results from the PPMI cohort
Authors: Eusebi Paolo , Romoli Michele , Paoletti Federico Paolini , Tambasco Nicola , Calabresi Paolo , Parnetti Lucilla 
Published: November 2018

AbstractLevodopa-induced dyskinesias (LID) negatively impact on the quality of life of patients with Parkinson’s disease (PD). We assessed the risk factors for LID in a cohort of de-novo PD patients enrolled in the Parkinson’s Progression Markers Initiative (PPMI). This retrospective cohort study included all PD patients enrolled in the PPMI cohort. Main outcome was the incidence rate of dyskinesia, defined as the first time the patient reported a non-zero score in the item “Time spent with dyskinesia” of the MDS-UPDRS part IV. Predictive value for LID development was assessed for clinical and demographical features, dopamine transporter imaging (DaTscan) pattern, cerebrospinal fluid (CSF) biomarkers (Aβ42, total tau, phosphorylated tau, total α synuclein) and genetic risk score for PD. Overall, data from 423 PD patients were analyzed. The cumulative incidence rate of LID was 27.4% (95% CI = 23.2–32.0%), with a mean onset time of 5.81 years from PD diagnosis. Multivariate Cox regression analysis showed several factors predicting LID development, including female gender (HR = 1.61, 95% CI = 1.05–2.47), being not completely functional independent as measured by the modified Schwab & England ADL scale (HR = 1.81, 95% CI = 0.98–3.38), higher MDS-UPDRS part III score (HR = 1.03, 95% CI = 1.00–1.05), postural instability gait disturbances or intermediate phenotypes (HR = 1.95, 95% CI = 1.28–2.96), higher DaTscan caudate asymmetry index (HR = 1.02, 95% CI = 1.00–1.03), higher polygenic genetic risk score (HR = 1.39, 95% CI = 1.08–1.78), and an anxiety trait (HR = 1.02, 95% CI = 1.00–1.04). In PD patients, cumulative levodopa exposure, female gender, severity of motor and functional impairment, non-tremor dominant clinical phenotype, genetic risk score, anxiety, and marked caudate asymmetric pattern at DaTscan at baseline represent independent risk factors for developing LID.
A bound on the superconducting transition temperature
Authors: Esterlis I. , Kivelson S. A. , Scalapino D. J. 
Published: November 2018

AbstractIt is notoriously difficult to make quantitative theoretical predictions of the superconducting transition temperature, Tc, either from first-principles or even from a knowledge of normal state properties. Ultimately, this reflects the fact that the energy scales involved in the superconducting state are extremely small in natural units, and that Tc depends exponentially on a subtle interplay between different interactions so that small uncertainties in microscopic processes can lead to order one effects on Tc. However, in some circumstances, it may be possible to determine (approximate) bounds on Tc. Here we propose such a bound for the conventional phonon-mediated mechanism of pairing with strongly retarded interactions, i.e. in the case in which $$\hbar \bar \omega \ll E_F$$

ℏ

ω

¯

≪

E

F

, where $$\bar \omega$$

ω

¯

is an appropriate characteristic phonon frequency and EF is the Fermi energy. Specifically, drawing on both empirical results (shown in Fig. 2 below) and recent results1 of determinant quantum Monte Carlo (DQMC) studies of the paradigmatic Holstein model, we propose that $$k_BT_c \le A_{\max }\hbar \bar \omega$$

k

B

T

c

≤

A

max

ℏ

ω

¯

, where Amax is a dimensionless number of order one that we estimate to be Amax ≈ 1/10.