bluuebunny/crossref_metadata_2025_split huggingface dataset:
Understanding Space Weather: Part III: The Sun’s Domain
Authors: Strong Keith , Viall Nicholeen , Schmelz Joan , Saba Julia 
Published: March 2017

AbstractThe Sun exports a continuous outflow of plasma into interplanetary space: the solar wind. The solar wind primarily comprises two components: high- and slow-speed flows. These move with velocities ranging from 200 to 800 km s-1 depending on the source of the particular flow. As well as its speed, the density, temperature, and even the composition of the solar wind change. Adding to its intrinsic variability, there are embedded transients resulting from flares and coronal mass ejections that further complicate its dynamics and space weather impacts. The solar wind interacts differently with each of the solar system objects it encounters based on their magnetic and atmospheric properties. Even more complex processes occur as the solar wind encounters the interstellar medium, at the outer boundaries of the Sun’s domain. The solar wind stretches to beyond 100 au (where 1 au ≡ 149 597 870 700 m) from the Sun, which means that Earth is essentially immersed in the very hot solar atmosphere, and that leads to many space weather impacts on life and society. The specific space weather impacts on Earth will be discussed in detail in the next two papers in this series.
Large Sensitivity of Near-Surface Vertical Vorticity Development to Heat Sink Location in Idealized Simulations of Supercell-Like Storms
Authors: Markowski Paul M. , Richardson Yvette P. 
Published: March 2017

Abstract
In idealized numerical simulations of supercell-like “pseudostorms” generated by a heat source and sink in a vertically sheared environment, a tornado-like vortex develops if air possessing large circulation about a vertical axis at the lowest model levels can be converged. This is most likely to happen if the circulation-rich air possesses only weak negative buoyancy (the circulation-rich air has a history of descent, so typically possesses at least some negative buoyancy) and is subjected to an upward-directed vertical perturbation pressure gradient force. This paper further explores the sensitivity of the development of near-surface vertical vorticity to the horizontal position of the heat sink. Shifting the position of the heat sink by only 2–3 km can significantly influence vortex intensity by altering both the baroclinic generation of circulation and the buoyancy of circulation-rich air. Many of the changes in the pseudostorms that arise from shifting the position of the heat sink would be difficult to anticipate. The sensitivity of the pseudostorms to heat sink position probably at least partly explains the well-known sensitivity of near-surface vertical vorticity development to the microphysics parameterizations in more realistic supercell storm simulations, as well as some of the failures of actual supercells to produce tornadoes in seemingly favorable environments.
Climatology and Interannual Variability of Boreal Spring Wet Season Precipitation in the Eastern Horn of Africa and Implications for Its Recent Decline
Authors: Liebmann Brant , Bladé Ileana , Funk Chris , Allured Dave , Quan Xiao-Wei , Hoerling Martin , Hoell Andrew , Peterson Pete , Thiaw Wassila M. 
Published: March 2017

Abstract
The 1981–2014 climatology and variability of the March–May eastern Horn of Africa boreal spring wet season are examined using precipitation, upper- and lower-level winds, low-level specific humidity, and convective available potential energy (CAPE), with the aim of better understanding the establishment of the wet season and the cause of the recent observed decline. At 850 mb, the development of the wet season is characterized by increasing specific humidity and winds that veer from northeasterly in February to southerly in June and advect moisture into the region, in agreement with an earlier study. Equally important, however, is a substantial weakening of the 200-mb climatological easterly winds in March. Likewise, the shutdown of the wet season coincides with the return of strong easterly winds in June. Similar changes are seen in the daily evolution of specific humidity and 200-mb wind when composited relative to the interannual wet season onset and end, with the easterlies decreasing (increasing) several days prior to the start (end) of the wet season. The 1981–2014 decrease in March–May precipitation has also coincided with an increase in 200-mb easterly winds, with no attendant change in specific humidity, leading to the conclusion that, while high values of specific humidity are an important ingredient of the wet season, the recent observed precipitation decline has resulted mostly from a strengthening of the 200-mb easterlies. This change in the easterly winds appears to be related to an increase in convection over the Indonesian region and in the associated outflow from that enhanced heat source.
Precipitation Analysis over the French Alps Using a Variational Approach and Study of Potential Added Value of Ground-Based Radar Observations
Authors: Birman Camille , Karbou Fatima , Mahfouf Jean-François , Lafaysse Matthieu , Durand Yves , Giraud Gérald , Mérindol Laurent , Hermozo Laura 
Published: March 2017

Abstract
A one-dimensional variational data assimilation (1DVar) method to retrieve profiles of precipitation in mountainous terrain is described. The method combines observations from the French Alpine region rain gauges and precipitation estimates from weather radars with background information from short-range numerical weather prediction forecasts in an optimal way. The performance of this technique is evaluated using measurements of precipitation and of snow depth during two years (2012/13 and 2013/14). It is shown that the 1DVar model allows an effective assimilation of measurements of different types, including rain gauge and radar-derived precipitation. The use of radar-derived precipitation rates over mountains to force the numerical snowpack model Crocus significantly reduces the bias and standard deviation with respect to independent snow depth observations. The improvement is particularly significant for large rainfall or snowfall events, which are decisive for avalanche hazard forecasting. The use of radar-derived precipitation rates at an hourly time step improves the time series of precipitation analyses and has a positive impact on simulated snow depths.
An Evaluation of Modeled Evaporation Regimes in Europe Using Observed Dry Spell Land Surface Temperature
Authors: Harris Phil P. , Folwell Sonja S. , Gallego-Elvira Belen , Rodríguez José , Milton Sean , Taylor Christopher M. 
Published: March 2017

Abstract
Soil moisture availability exerts control over the land surface energy partition in parts of Europe. However, determining the strength and variability of this control is impeded by the lack of reliable evaporation observations at the continental scale. This makes it difficult to refine the broad range of soil moisture–evaporation behaviors across global climate models (GCMs). Previous studies show that satellite observations of land surface temperature (LST) during rain-free dry spells can be used to diagnose evaporation regimes at the GCM gridbox scale. This relative warming rate (RWR) diagnostic quantifies the increase in dry spell LST relative to air temperature and is used here to evaluate a land surface model (JULES) both offline and coupled to a GCM (HadGEM3-A). It is shown that RWR can be calculated using outputs from an atmospheric GCM provided the satellite clear-sky sampling bias is incorporated. Both offline JULES and HadGEM3-A reproduce the observed seasonal and regional RWR variations, but with weak springtime RWRs in central Europe. This coincides with sustained bare soil evaporation (Ebs) during dry spells, reflecting previous site-level JULES studies in Europe. To assess whether RWR can discriminate between surface descriptions, the bare soil surface conductance and the vegetation root profile are revised to limit Ebs. This increases RWR by increasing the occurrence of soil moisture–limited dry spells, yielding more realistic springtime RWRs as a function of antecedent precipitation but poorer relationships in summer. This study demonstrates the potential for using satellite LST to assess evaporation regimes in climate models.
A New Inversion Method to Obtain Upper-Ocean Current-Depth Profiles Using X-Band Observations of Deep-Water Waves
Authors: Campana Jeffrey , Terrill Eric J. , de Paolo Tony 
Published: March 2017

AbstractA new method for estimating current-depth profiles from observations of wavenumber-dependent Doppler shifts of the overlying ocean wave field is presented. Consecutive scans of marine X-band backscatter provide wave field measurements in the time–space domain that transform into the directional wavenumber–frequency domain via a 3D fast Fourier transform (FFT). Subtracting the linear dispersion shell yields Doppler shift observations in the form of (kx, ky, Δω) triplets. A constrained linear regression technique is used to extract the wavenumber-dependent effective velocities, which represent a weighted depth average of the Eulerian currents (Stewart and Joy). This new method estimates these Eulerian currents from the effective velocities via the inversion of the integral relationship, which was first derived by Stewart and Joy. To test the effectiveness of the method, the inverted current profiles are compared to concurrent ADCP measurements. The inversion method is found to successfully predict current behavior, with a depth-average root-mean-square (RMS) error less than 0.1 m s−1 for wind speeds greater than 5 m s−1 and a broad wave spectrum. The ability of the inversion process to capture the vertical structure of the currents is assessed using a time-average RMS error during these favorable conditions. The time-averaged RMS error is found to be less than 0.1 m s−1 for depths shallower than 20 m, approximately twice the depth of existing methods of estimating current shear from wave field measurements.
Mesocyclone-Targeted Doppler Velocity Dealiasing
Authors: Xu Qin , Nai Kang 
Published: March 2017

AbstractThe alias-robust variational (AR-Var) analysis developed originally for dealiasing raw velocities scanned from winter ice storms by operational WSR-88D radars was recently extended for dealiasing raw velocities scanned from all storms to increase the dealiased data coverage. The extended AR-Var (eAR-Var)-based dealiasing can detect tornadic mesocyclones and estimate their vortex center locations as by-products, but its dealiased data often leave rejected data holes in the critical vortex core and vicinity areas of detected mesocyclones. To solve this problem, a mesocyclone-targeted dealiasing routine is developed in this paper to perform two additional steps after the eAR-Var dealiasing. In particular, a reference check is performed in the first step, with the required reference velocities produced by a newly designed alias-robust vortex wind analysis to recover the rejected data in the vortex core, and then a continuity check is performed in the second step to recover the remaining rejected data around and beyond the vortex core. The mesocyclone-targeted dealiasing is tested extensively with severely aliased velocity data scanned from tornadic storms and is found to be effective and efficient for recovering the rejected data in and around the vortex core of the detected mesocyclone, provided the required data coverage conditions and analysis acceptance conditions are satisfied.
Remote Measurements of Tides and River Slope Using an Airborne Lidar Instrument
Authors: Hudson Austin S. , Talke Stefan A. , Branch Ruth , Chickadel Chris , Farquharson Gordon , Jessup Andrew 
Published: March 2017

AbstractTides and river slope are fundamental characteristics of estuaries, but they are usually undersampled due to deficiencies in the spatial coverage of water level measurements. This study aims to address this issue by investigating the use of airborne lidar measurements to study tidal statistics and river slope in the Columbia River estuary. Eight plane transects over a 12-h period yield at least eight independent measurements of water level at 2.5-km increments over a 65-km stretch of the estuary. These data are fit to a sinusoidal curve and the results are compared to seven in situ gauges. In situ– and lidar-based tide curves agree to within a root-mean-square error of 0.21 m, and the lidar-based river slope estimate of 1.8 × 10−5 agrees well with the in situ–based estimate of 1.4 × 10−5 (4 mm km−1 difference). Lidar-based amplitude and phase estimates are within 10% and 8°, respectively, of their in situ counterparts throughout most of the estuary. Error analysis suggests that increased measurement accuracy and more transects are required to reduce the errors in estimates of tidal amplitude and phase. However, the results validate the use of airborne remote sensing to measure tides and suggest this approach can be used to systematically study water levels at a spatial density not possible with in situ gauges.
Diagnosis of a North American Polar–Subtropical Jet Superposition Employing Piecewise Potential Vorticity Inversion
Authors: Winters Andrew C. , Martin Jonathan E. 
Published: March 2017

Abstract
The polar jet (PJ) and subtropical jet (STJ) often reside in different climatological latitude bands. On occasion, the meridional separation between the two jets can vanish, resulting in a relatively rare vertical superposition of the PJ and STJ. A large-scale environment conducive to jet superposition can be conceptualized as one that facilitates the simultaneous advection of tropopause-level potential vorticity (PV) perturbations along the polar and subtropical waveguides toward midlatitudes. Once these PV perturbations are transported into close proximity to one another, interactions between tropopause-level, lower-tropospheric, and diabatically generated PV perturbations work to restructure the tropopause into the two-step, pole-to-equator tropopause structure characteristic of a jet superposition.
This study employs piecewise PV inversion to diagnose the interactions between large-scale PV perturbations throughout the development of a jet superposition during the 18–20 December 2009 mid-Atlantic blizzard. While the influence of PV perturbations in the lower troposphere as well as those generated via diabatic processes were notable in this case, tropopause-level PV perturbations played the most substantial role in restructuring the tropopause prior to jet superposition. A novel PV partitioning scheme is presented that isolates PV perturbations associated with the PJ and STJ, respectively. Inversion of the jet-specific PV perturbations suggests that these separate features make distinct contributions to the restructuring of the tropopause that characterizes the development of a jet superposition.
Optical coherence tomography follow-up 18 months after titanium-nitride-oxide-coated versus everolimus-eluting stent implantation in patients with acute coronary syndrome
Authors: Karjalainen Pasi , Paana Tuomas , Ylitalo Antti , Sia Jussi , Nammas Wail 
Published: March 2017

Background Inadequate neointimal coverage of stent struts is associated with late stent thrombosis. Purpose To demonstrate the extent of neointimal coverage and strut malapposition in titanium-nitride-oxide-coated bioactive stents (BAS) versus everolimus-eluting stents (EES) by optical coherence tomography (OCT) performed at 18-month follow-up. Material and Methods In the BASE-ACS trial, 827 patients presenting with acute coronary syndrome were randomized to receive either BAS or EES. Forty patients (20 BAS, 20 EES) underwent OCT at 18-month follow-up for evaluation of stent strut coverage, malapposition, and neointimal hyperplasia (NIH). Primary endpoint was binary stent strut coverage (ratio of covered struts to all analyzed struts multiplied by 100). Co-primary endpoint was the percentage of malapposed struts. Results We analyzed 3465 struts in 330 cross-sections of BAS and 3327 struts in 316 cross-sections of EES. Binary stent strut coverage, based on strut-level analysis, was higher with BAS versus EES (99.5% versus 94.2%, respectively; P < 0.001), the strut-level percentage of malapposed struts was lower with BAS (0.6% versus 2.5%, respectively; P < 0.001). Yet, the mean NIH thickness was greater with BAS (237 ± 125 versus 108 ± 62 µm, respectively; P < 0.001). Conclusion In the current post-hoc analysis with OCT performed at 18 months, binary strut coverage, based on strut-level analysis, was higher with BAS versus EES; strut-level malapposed struts were fewer with BAS; yet, BAS induced thicker NIH.
Intravoxel incoherent motion MRI for monitoring the therapeutic response of hepatocellular carcinoma to sorafenib treatment in mouse xenograft tumor models
Authors: Lee Yedaun , Lee Seung Soo , Cheong Hyunhee , Lee Chang Kyung , Kim Namkug , Son Woo-Chan , Hong Seung Mo 
Published: March 2017

Background With the introduction of targeted therapies, there has been a growing need for non-invasive imaging methods which accurately evaluate therapeutic effects and overcome the limitations of tumor size-based therapeutic response assessments. Purpose To assess diagnostic values of intra-voxel incoherent motion (IVIM) imaging in evaluating therapeutic effects of sorafenib on hepatocellular carcinoma (HCC) using mouse xenograft model. Material and Methods Twenty-four mice bearing Huh-7 were divided into a control group and two treatment groups received sorafenib doses of 5 mg/kg (5 mg-Tx) or 30 mg/kg (30 mg-Tx). IVIM imaging was performed using 10 b-values (0–900 s/mm2). The apparent diffusion coefficient (ADC), diffusion coefficient ( D), and perfusion fraction ( f) were measured for whole tumors and tumor periphery. Changes between baseline and post-treatment parameters ( Δ ADC, Δ D, and Δ f) were calculated, and these parameters were compared with microvessel density (MVD) and area of tumor cell death. Results The post-treatment f and Δ f for tumor periphery were significantly higher in control group, followed by 5 mg-Tx and 30 mg-Tx ( P < 0.001). MVD showed significant positive correlation with post-treatment f ( r = 0.584, P = 0.003) and negative correlation with D ( r = –0.495, P = 0.014) for tumor periphery, while no parameter showed significant correlation with area of tumor cell death. Conclusion The f is significantly correlated with MVD of HCC, and could potentially be used to evaluate the anti-angiogenic effects of sorafenib.
Pentoxifylline plus ACEIs/ARBs for proteinuria and kidney function in chronic kidney disease: a meta-analysis
Authors: Liu Dong , Wang Li-na , Li Hong-xia , Huang Ping , Qu Liang-bo , Chen Fei-yan 
Published: March 2017

Objective This meta-analysis aimed to investigate the efficacy and safety of pentoxifylline (PTF) plus angiotensin-converting enzyme inhibitors (ACEIs)/angiotensin receptor blockers (ARBs) for proteinuria and kidney function in chronic kidney disease (CKD). Methods CENTRAL, EMBASE, Ovid-MEDLINE, PubMed, and CNKI were searched for relevant, randomized, controlled trials (RCTs). A meta-analysis was performed to review the effect of PTF plus ACEIs/ARBs vs. ACEIs/ARBs alone on proteinuria and kidney function in CKD. Results Eleven RCTs including 705 patients were retrieved. PTF plus ACEI/ARB treatment significantly decreased proteinuria in patients with CKD within 6 months (standard mean difference [SMD] −0.52; 95% CI −0.90 to 0.15; I2 = 68%) and significantly attenuated a decrease in estimated glomerular filtration rate (eGFR) in patients with stages 3–5 CKD after 6 months of treatment (standard mean difference [SMD] 0.30; confidence limit [Cl] 95% CI 0.06 to 0.54; I2 = 0%). PTF plus ACEIs/ARBs for 9 to 12 months significantly reduced albuminuria in patients with CKD (SMD−0.30, 95% CI −0.57 to 0.03; I2 = 0%) and alleviated the decline in eGFR in patients with stages 3–5 CKD (SMD 0.51; 95% CI 0.06 to 0.96; I2 = 61%). Conclusion The combination of an ACEI or ARB and PTF has a protective effect in reducing proteinuria by ameliorating the decline in eGFR in patients with stages 3–5 CKD.
A Targeted Self-Management Approach for Reducing Stroke Risk Factors in African American Men Who Have Had a Stroke or Transient Ischemic Attack
Authors: Sajatovic Martha , Tatsuoka Curtis , Welter Elisabeth , Colon-Zimmermann Kari , Blixen Carol , Perzynski Adam T. , Amato Shelly , Cage Jamie , Sams Johnny , Moore Shirley M. , Pundik Svetlana , Sundararajan Sophia , Modlin Charles , Sila Cathy 
Published: March 2017

Purpose: This study compared a novel self-management (TargetEd MAnageMent Intervention [TEAM]) versus treatment as usual (TAU) to reduce stroke risk in African American (AA) men. Design: Six-month prospective randomized controlled trial with outcomes evaluated at baseline, 3 months, and 6 months. Setting: Academic health center. Participants: Thirty-eight (age < 65) AA men who had a stroke or transient ischemic attack and a Barthel index score of >60 were randomly assigned to TEAM (n = 19) or TAU (n = 19). Intervention: Self-management training, delivered in 1 individual and 4 group sessions (over 3 months). Measures: Blood pressure, glycosylated hemoglobin (HbA1c), lipids, medication adherence, weight, and standardized measures of health behaviors (diet, exercise, smoking, substances), depression, and quality of life. Qualitative assessments evaluated the perspectives of TEAM participants. Analysis: T tests for paired differences and nonparametric tests. Thematic content qualitative analysis. Results: Mean age was 52.1 (standard deviation [SD] = 7.4) and mean body mass index was 31.4 (SD = 7.4). Compared to TAU, TEAM participants had significantly lower mean systolic blood pressure by 24 weeks, and there was also improvement in HbA1c and high-density lipoprotein cholesterol ( P = .03). Other biomarker and health behaviors were similar between groups. Qualitative results suggested improved awareness of risk factors as well as positive effects of group support.