bluuebunny/crossref_metadata_2025_split huggingface dataset:
Direct numerical simulation of open-channel flow over smooth-to-rough and rough-to-smooth step changes
Authors: Rouhi Amirreza , Chung Daniel , Hutchins Nicholas 
Published: March 2019

Direct numerical simulations (DNS) are reported for open-channel flow over streamwise-alternating patches of smooth and fully rough walls. The rough patch is a three-dimensional sinusoidal surface. Owing to the streamwise periodicity, the flow configuration consists of a step change from smooth to rough, and a step change from rough to smooth. The friction Reynolds number varies from 437 over the smooth patch to 704 over the rough patch. Through the fully resolved DNS dataset it is possible to explore many detailed aspects of this flow. Two aspects motivate this work. The first one is the equilibrium assumption that has been widely used in both experiments and computations. However, it is not clear where this assumption is valid. The detailed DNS data reveal a significant departure from equilibrium, in particular over the smooth patch. Over this patch, the mean velocity is recovered up to the beginning of the log layer after a fetch of five times the channel height. However, over the rough patch, the same recovery level is reached after a fetch of two times the channel height. This conclusion is arrived at by assuming that an error of up to 5 % is acceptable and the log layer, classically, starts from 30 wall units above the wall. The second aspect is the reported internal boundary-layer (IBL) growth rates in the literature, which are inconsistent with each other. This is conjectured to be partly caused by the diverse IBL definitions. Five common definitions are applied for the same DNS dataset. The resulting IBL thicknesses are different by 100 %, and their apparent power-law exponents are different by 50 %. The IBL concept, as a layer within which the flow feels the surface underneath, is taken as the basis to search for the proper definition. The definition based on the logarithmic slope of the velocity profile, as proposed by Elliot (Trans. Am. Geophys. Union, vol. 39, 1958, pp. 1048–1054), yields better consistency with this concept based on turbulence characteristics.
Bias in Self-reported Voting and How it Distorts Turnout Models: Disentangling Nonresponse Bias and Overreporting Among Danish Voters
Authors: Dahlgaard Jens Olav , Hansen Jonas Hedegaard , Hansen Kasper M. , Bhatti Yosef 
Published: March 2019

Most nonexperimental studies of voter turnout rely on survey data. However, surveys overestimate turnout because of (1) nonresponse bias and (2) overreporting. We investigate this possibility using a rich dataset of Danish voters, which includes validated turnout indicators from administrative data for both respondents and nonrespondents, as well as respondents’ self-reported voting from the Danish National Election Studies. We show that both nonresponse bias and overreporting contribute significantly to overestimations of turnout. Further, we use covariates from the administrative data available for both respondents and nonrespondents to demonstrate that both factors also significantly bias the predictors of turnout. In our case, we find that nonresponse bias and overreporting masks a gender gap of two and a half percentage points in women’s favor as well as a gap of 25 percentage points in ethnic Danes’ favor compared with Danes of immigrant heritage.
CENSURING SOUNDS: TAPES, TASTE, AND THE CREATION OF EGYPTIAN CULTURE
Authors: Simon Andrew 
Published: March 2019

AbstractIn this article, I argue that audiocassette technology decentralized state-controlled Egyptian media long before the advent of al-Jazeera and the Internet. By enabling any citizen to become a cultural producer, as opposed to a mere consumer, the mass medium and its users sparked significant anxiety in the mid-to-late 20th century, when contentious cassette recordings led many local critics to assert that “vulgar” tapes were poisoning public taste, undermining high culture, and endangering Egyptian society. This article breaks down these arguments and shows that audiotapes actually broadcast a vast variety of voices. Thus, underlying many criticisms of cassette content, I contend, was not simply a concern for aesthetic sensibilities but a desire to dictate who created Egyptian culture during a time of tremendous change. By unpacking these discussions, this article harnesses Egypt as a case study to enhance prevailing investigations of sound, popular culture, and mass media in Middle East studies.
Longitudinal Changes in Disability Rating Scale Scores: A Secondary Analysis Among Patients With Severe TBI Enrolled in the Epo Clinical Trial
Authors: Benoit Julia S. , Hannay H. Julia , Yamal Jose-Miguel , Francis David J. , Aisiku Imoigele , Robertson Claudia 
Published: March 2019

AbstractObjectives:Long-term neurological response to treatment after a severe traumatic brain injury (sTBI) is a dynamic process. Failure to capture individual heterogeneity in recovery may impact findings from single endpoint sTBI randomized controlled trials (RCT). The present study re-examined the efficacy of erythropoietin (Epo) and transfusion thresholds through longitudinal modeling of sTBI recovery as measured by the Disability Rating Scale (DRS). This study complements the report of primary outcomes in the Epo sTBI RCT, which failed to detect significant effects of acute treatment at 6 months post-injury.Methods:We implemented mixed effects models to characterize the recovery time-course and to examine treatment efficacy as a function of time post-injury and injury severity.Results:The inter-quartile range (25th–75thpercentile) of DRS scores was 20–28 at week1; 8–24 at week 4; and 3–17 at 6 months. TBI severity group was found to significantly interact with Epo randomization group on mean DRS recovery curves. No significant differences in DRS recovery were found in transfusion threshold groups.Conclusions:This study demonstrated the value of taking a comprehensive view of recovery from sTBI in the Epo RCT as a temporally dynamic process that is shaped by both treatment and injury severity, and highlights the importance of the timing of primary outcome measurement. Effects of Epo treatment varied as a function of injury severity and time. Future studies are warranted to understand the possible moderating influence of injury severity on treatment effects pertaining to sTBI recovery. (JINS, 2019,25, 293–301)
Understanding structural plasticity in the bilingual brain: The Dynamic Restructuring Model
Authors: Pliatsikas Christos 
Published: March 2019

AbstractResearch on the effects of bi- and multi-lingualism on brain structure has so far yielded variable patterns. Although it cannot be disputed that learning and using additional languages restructures grey (cortical, subcortical and cerebellar) and white matter in the brain, both increases and reductions in regional volume and diffusivity have been reported. This paper revisits the available evidence from simultaneous and sequential bilinguals, multilinguals, interpreters, bimodal bilinguals, children, patients and healthy older adults from the perspective of experience-based neuroplasticity. The Dynamic Restructuring Model (DRM) is then presented: a three-stage model accounting for, and reinterpreting, all the available evidence by proposing a time-course for the reported structural adaptations, and by suggesting that these adaptations are dynamic and depend on the quantity and quality of the language learning and switching experience. This is followed by suggestions for future directions for the emerging field of bilingualism-induced neuroplasticity.
Examining the Effect of Evaporation Field on Boron Measurements in SiGe: Insights into Improving the Relationship Between APT and SIMS Measurements of Boron
Authors: Martin Andrew J. , Yatzor Brett 
Published: March 2019

AbstractUnderstanding and resolving discrepancies between atom probe tomography (APT) and secondary ion mass spectrometry (SIMS) measurements of B dopants in Si-based materials has long been a problem for those in the semiconductor community who wish to measure B within the source/drain SiGe of a device. APT data collection of Si-based materials is typically optimized for Si, which is logical, but perhaps not ideal for field evaporation of B. Increasing the evaporation field well beyond the typically used 28Si2+:28Si+ ratio of approximately 10:1 up to a ratio of ~200:1 is demonstrated to improve B detection while retaining well-matched Si and Ge concentrations with respect to those measured by SIMS. A range of evaporation conditions are examined from a very low field with high laser energy to an extremely high field with extremely low laser energy demonstrating problems at both far ends of the spectrum and a sweet spot when the operating conditions used produce a 28Si2+:28Si+ ratio of approximately 200:1 (in terms of total counts of each ionization state), which is more than an order of magnitude higher than normally used conditions and results in nicely matched B, Si, and Ge APT measurements with those of SIMS.
International authority and the emergency problematique: IO empowerment through crises
Authors: Kreuder-Sonnen Christian 
Published: March 2019

AbstractThis paper applies the concept of emergency powers to the crisis politics of international organizations (IOs). In the recent past, IOs like the UN Security Council, the WHO, and the EU have reacted to large-scale crises by resorting to assertive governance modes bending the limits of their competence and infringing on the rights of the rule-addressees. In contrast to rational and sociological institutionalist notions of mission creep, this paper submits that this practice constitutes ‘authority leaps’ which follow a distinct logic of exceptionalism: the expansion of executive discretion in both the horizontal (lowering of checks and balances) and the vertical (reduction of legal protection of subjects) dimension, justified by reference to political necessity. This ‘IO exceptionalism’, as argued here, represents a class of events which is observable across fundamentally different international institutions and issue areas. It is important not least because emergency politics tend to leave longer-term imprints on a polity’s authority structures. This article shows that the emergency powers of IOs have a tendency to normalize and become permanent features of the institution. Thus IO exceptionalism and its ratcheting up represent a mechanism of abrupt but sustainable authority expansion at the level of IOs.
Origin of High‐Frequency Radiation During Laboratory Earthquakes
Authors: Marty S. , Passelègue F. X. , Aubry J. , Bhat H. S. , Schubnel A. , Madariaga R. 
Published: March 2019

AbstractWe monitor dynamic rupture propagation during laboratory stick‐slip experiments performed on saw‐cut Westerly granite under upper crustal conditions (10–90 MPa). Spectral analysis of high‐frequency acoustic waveforms provided evidence that energy radiation is enhanced with stress conditions and rupture velocity. Using acoustic recordings band‐pass filtered to 400–800 kHz (7–14 mm wavelength) and high‐pass filtered above 800 kHz, we back projected high‐frequency energy generated during rupture propagation. Our results show that the high‐frequency radiation originates behind the rupture front during propagation and propagates at a speed close to that obtained by our rupture velocity inversion. From scaling arguments, we suggest that the origin of high‐frequency radiation lies in the fast dynamic stress‐drop in the breakdown zone together with off‐fault coseismic damage propagating behind the rupture tip. The application of the back‐projection method at the laboratory scale provides new ways to locally investigate physical mechanisms that control high‐frequency radiation.
EMIC Wave Properties Associated With and Without Injections in The Inner Magnetosphere
Authors: Jun C.‐W. , Yue C. , Bortnik J. , Lyons L. R. , Nishimura Y. , Kletzing C. 
Published: March 2019

AbstractTo understand the generation and propagation processes of electromagnetic ion cyclotron (EMIC) waves under different geomagnetic conditions in the inner magnetosphere, we performed a statistical study of EMIC wave properties observed by the Van Allen Probes from February 2013 to December 2016. We divided EMIC waves into two groups: those associated with and those occurring without injections observed by the Geostationary Operational Environmental Satellites (GOES‐13 and GOES‐15). We found that the EMIC wave polarization sense ε increased and the normalized frequency X decreased with increasing |MLAT|. Inside the plasmasphere, He+ EMIC waves were predominantly observed with left‐hand polarization (ε< −0.3) and higher wave normal angles (θk = 30–40° ). Those associated with injections showed the most intense wave power at 14–16 MLT, compared to periods without injections when these waves exhibit a similar wave power but on the dayside. H+ EMIC waves were predominantly observed outside the plasmasphere on the dayside and showed a mixture of left‐hand and linear polarizations (ε = −0.3–0.0) with lower wave normal angles (θk = 20–30° ) regardless of injections. Moreover, H+ EMIC waves were accompanied by a solar wind dynamic pressure enhancement (ΔPsw = 0.5 nPa). From these observations, we suggest that hot injected plasma contributes to the generation of intense He+ EMIC waves in the afternoon sector. A mixture of expanding cold plasmaspheric ions and coexisting hot ring current ions acts as the free energy source for He+ EMIC waves on the dayside during quiet times. Solar wind dynamic pressure enhancements are likely the major driver of H+ EMIC waves outside the plasmasphere.
Along‐Strike Variation and Migration of Long‐Term Slow Slip Events in the Western Nankai Subduction Zone, Japan
Authors: Takagi Ryota , Uchida Naoki , Obara Kazushige 
Published: March 2019

AbstractWe detected 24 long‐term slow slip events (SSEs) in the western Nankai subduction zone, Japan, from 1996 to 2017 using a newly developed method: grid‐based determination of slow slip events (GriD‐SSEs). GriD‐SSE systematically detects long‐term SSEs and determines their fault parameters by fitting modeled displacement time series to observed Global Navigation Satellite System data. The detected SSEs included 11 previously undocumented events. The results suggest an along‐strike segmentation of long‐term SSEs. The along‐strike variations in SSE recurrence intervals and total slip amounts appear to correlate with the variation of updip interplate locking. Long‐term SSEs are less frequent in the downdip extensions of the Nankai megathrust (MW 8–9) and Hyuga‐nada earthquakes (MW 7.5), with ~6‐year recurrence intervals and total slip amounts that account for only 10–20% of the plate convergence. However, long‐term SSEs do occur frequently downdip of the Hyuga‐nada stable sliding zone and of the gap between the Nankai and Hyuga‐nada earthquakes, with 2‐ to 3‐year recurrence intervals and total slip amounts that account for 50–60% of the plate convergence. This correlation suggests that the long‐term SSE activity is controlled by the updip locked areas owing to the stress shadowing effect. We also observed that the long‐term SSEs repeatedly migrated in the downdip regions from the southwestern creeping zone to the northeastern Nankai megathrust locked zone. This SSE migration may represent the current state of stress accumulation and release processes that are controlled by the along‐strike variations in interplate coupling along the entire western Nankai subduction zone.
Retrieval of Interstation Local Body Waves From Teleseismic Coda Correlations
Authors: Saygin E. , Kennett B. L. N. 
Published: March 2019

AbstractWe retrieve the local P wave empirical Green's functions between the elements of five different regional arrays across the globe by cross‐correlating and bin stacking the teleseismic earthquake coda waves recorded at each array. The stack is made using the coda of P and S wave phases for events in the distance range from 40° to 50° from the center of the array. With a sequence of time windows along the coda the various body wave arrivals can be tracked, using record sections constructed by binning the stacked interstation correlograms in less than 1‐km distance increments. The correlation of the coda part of each principal seismic phase produces highly coherent interstation arrivals for different analysis windows. Such arrivals can be reproduced by just stacking 100 arrivals from a pool of more than a thousand events, showing the stability of the observed Green's functions. Modeling for the structure beneath the Warramunga array in the Northern Territory, Australia, demonstrates that these arrivals correspond to multiply reflected arrivals from layers at different depths. The recovery of high‐frequency interstation body waves from the teleseismic earthquake coda opens the prospect of conducting local high‐resolution seismic imaging with teleseismic energy.
Prognostic Precipitation in the MIROC6‐SPRINTARS GCM: Description and Evaluation Against Satellite Observations
Authors: Michibata Takuro , Suzuki Kentaroh , Sekiguchi Miho , Takemura Toshihiko 
Published: March 2019

AbstractA comprehensive two‐moment microphysics scheme is incorporated into the MIROC6‐SPRINTARS general circulation model (GCM). The new scheme includes prognostic precipitation for both rain and snow and considers their radiative effects. To evaluate the impacts of applying different treatments of precipitation and the associated radiative effect, we perform climate simulations employing both the traditional diagnostic and new prognostic precipitation schemes, the latter also being tested with and without incorporating the radiative effect of snow. The prognostic precipitation, which maintains precipitation in the atmosphere across multiple time steps, models the ratio of accretion to autoconversion as being approximately an order of magnitude higher than that for the diagnostic scheme. Such changes in microphysical process rates tend to reduce the cloud water susceptibility as the autoconversion process is the only pathway through which aerosols can influence rain formation. The resultant anthropogenic aerosol effect is reduced by approximately 21% in the prognostic precipitation scheme. Modifications to the microphysical process rates also change the vertical distribution of hydrometeors in the manner that increases the fractional occurrence of single‐layered warm clouds by 38%. The new scheme mitigates the excess of supercooled liquid water produced by the previous scheme and increases the total mass of ice hydrometeors. Both characteristics are consistent with CloudSat/CALIPSO retrievals. The radiative effect of snow is significant at both longwave and shortwave (6.4 and 5.1 W/m2 in absolute values, respectively) and can alter the precipitation fields via energetic controls on precipitation. These results suggest that the prognostic precipitation scheme, with its radiative effects incorporated, makes an indispensable contribution to improving the reliability of climate modeling.
Winter Precipitation and Summer Temperature Predict Lake Water Quality at Macroscales
Authors: Collins S. M. , Yuan S. , Tan P. N. , Oliver S. K. , Lapierre J. F. , Cheruvelil K. S. , Fergus C. E. , Skaff N. K. , Stachelek J. , Wagner T. , Soranno P. A. 
Published: March 2019

AbstractClimate change can have strong effects on aquatic ecosystems, including disrupting nutrient cycling and mediating processes that affect primary production. Past studies have been conducted mostly on individual or small groups of ecosystems, making it challenging to predict how future climate change will affect water quality at broad scales. We used a subcontinental‐scale database to address three objectives: (1) identify which climate metrics best predict lake water quality, (2) examine whether climate influences different nutrient and productivity measures similarly, and (3) quantify the potential effects of a changing climate on lakes. We used climate data to predict lake water quality in ~11,000 north temperate lakes across 17 U.S. states. We developed a novel machine learning method that jointly models different measures of water quality using 48 climate metrics and accounts for properties inherent in macroscale data (e.g., spatial autocorrelation). Our results suggest that climate metrics related to winter precipitation and summer temperature were strong predictors of lake nutrients and productivity. However, we found variation in the magnitude and direction of the relationship between climate and water quality. We predict that a likely future climate change scenario of warmer summer temperatures will lead to increased nutrient concentrations and algal biomass across lakes (median ~3%–9% increase), whereas increased winter precipitation will have highly variable effects. Our results emphasize the importance of heterogeneity in the response of individual ecosystems to climate and are a caution to extrapolating relationships across space.
SUMOylation of G9a regulates its function as an activator of myoblast proliferation
Authors: Srinivasan Shruti , Shankar Shilpa Rani , Wang Yaju , Taneja Reshma 
Published: March 2019

AbstractThe lysine methyltransferase G9a plays a role in many cellular processes. It is a potent repressor of gene expression, a function attributed to its ability to methylate histone and non-histone proteins. Paradoxically, in some instances, G9a can activate gene expression. However, regulators of G9a expression and activity are poorly understood. In this study, we report that endogenous G9a is SUMOylated in proliferating skeletal myoblasts. There are four potential SUMOylation consensus motifs in G9a. Mutation of all four acceptor lysine residues [K79, K152, K256, and K799] inhibits SUMOylation. Interestingly, SUMOylation does not impact G9a-mediated repression of MyoD transcriptional activity or myogenic differentiation. In contrast, SUMO-defective G9a is unable to enhance proliferation of myoblasts. Using complementation experiments, we show that the proliferation defect of primary myoblasts from conditional G9a-deficient mice is rescued by re-expression of wild-type, but not SUMOylation-defective, G9a. Mechanistically, SUMOylation acts as signal for PCAF (P300/CBP-associated factor) recruitment at E2F1-target genes. This results in increased histone H3 lysine 9 acetylation marks at E2F1-target gene promoters that are required for S-phase progression. Our studies provide evidence by which SUMO modification of G9a influences the chromatin environment to impact cell cycle progression.