bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sensitivity of C-reactive protein cut-off values for pyogenic spinal infection in the emergency department
Authors: Davis William T. , April Michael D. , Mehta Sumeru , Long Brit , Boys Gregory , Shroyer Steven 
Published: June 2020

ABSTRACTObjectivesThe aim of this study was to describe the sensitivity of various C-reactive protein (CRP) cut-off values to identify patients requiring magnetic resonance imaging evaluation for pyogenic spinal infection among emergency department (ED) adults presenting with neck or back pain.MethodsWe prospectively enrolled a convenience series of adults presenting to a community ED with neck or back pain in whom ED providers had concern for pyogenic spinal infection in a derivation cohort from 2004 to 2010 and a validation cohort from 2010 to 2018. The validation cohort included only patients with pyogenic spinal infection. We analysed diagnostic test characteristics of various CRP cut-off values.ResultsWe enrolled 232 patients and analysed 201 patients. The median age was 55 years, 43.8% were male, 4.0% had history of intravenous drug use, and 20.9% had recent spinal surgery. In the derivation cohort, 38 (23.9%) of 159 patients had pyogenic spinal infection. Derivation sensitivity and specificity of CRP cut-off values were > 3.5 mg/L (100%, 24.8%), > 10 mg/L (100%, 41.3%), > 30 mg/L (100%, 61.2%), and > 50 mg/L (89.5%, 69.4%). Validation sensitivities of CRP cut-off values were > 3.5 mg/L (97.6%), > 10 mg/L (97.6%), > 30 mg/L (90.4%), and > 50 mg/L (85.7%).ConclusionsCRP cut-offs beyond the upper limit of normal had high sensitivity for pyogenic spinal infection in this adult ED population. Elevated CRP cut-off values of 10 mg/L and 30 mg/L require validation in other settings.
Symbolic dynamics in mean dimension theory
Authors: SHINODA MAO , TSUKAMOTO MASAKI 
Published: June 2020

AbstractFurstenberg [Disjointness in ergodic theory, minimal sets, and a problem in Diophantine approximation.Math. Syst. Theory1(1967), 1–49] calculated the Hausdorff and Minkowski dimensions of one-sided subshifts in terms of topological entropy. We generalize this to$\mathbb{Z}^{2}$-subshifts. Our generalization involves mean dimension theory. We calculate the metric mean dimension and the mean Hausdorff dimension of$\mathbb{Z}^{2}$-subshifts with respect to a subaction of$\mathbb{Z}$. The resulting formula is quite analogous to Furstenberg’s theorem. We also calculate the rate distortion dimension of$\mathbb{Z}^{2}$-subshifts in terms of Kolmogorov–Sinai entropy.
Migrant Rights, Agency, and Vulnerability: Navigating Contradictions in the Eurasian Region
Authors: Schenk Caress 
Published: June 2020

AbstractMigrants are often presented in simplified terms that focus on the threats they experience or pose to the host society. This produces an image of migrants who have no agency and are victims of their circumstances or who respond to their circumstances by turning to crime and illegality. In this special issue, we reframe migration by highlighting how migrants leverage the various vulnerabilities they encounter, turning them into agency and self-sufficiency. We explore different types of vulnerability and agency for migrants in the Eurasian region, which often originate from the same sources, including structural factors, state and governance practices, social networks, and gender roles. Through interactions with a variety of state and nonstate actors, migrants have the ability to make choices that reduce uncertainty and risk in their migration environment and on returning home. These choices coexist with vulnerability and a lack of formal rights but do not replace them, creating complex and contingent relationships between precarity and agency.
The Curse of Displacement: Local Narratives of Forced Expulsion and the Appropriation of Abandoned Property in Abkhazia
Authors: Peinhopf Andrea 
Published: June 2020

AbstractSince the end of the Georgian-Abkhaz war, the often-precarious status of the Georgians displaced from Abkhazia has received significant academic attention. In contrast, the consequences of displacement from the reverse perspective—how it has affected the people who stayed behind—remains underanalyzed. Drawing on narratives collected during several months of ethnographic fieldwork, this article argues that although ethnic Abkhazians see themselves as victims of ethnic violence rather than perpetrators, the re-distribution of Georgian property nevertheless caused significant distress. Many condemned the practice of appropriation, suggesting that taking what is not one’s own is not only a violation of the property of the original owner, but also of the Abkhaz moral code and therefore shameful. To them, the trophy houses were a curse, both literally—as spaces haunted by former occupants—and metaphorically, as a source and reminder of a certain “moral corruption” within Abkhazian society. However, while the stories around the trophy houses reflect substantial intra-communal divisions, I suggest that they are also an expression of a shared postwar experience. Like the horror stories of Georgian violence, and the tales of Abkhaz heroism, they have become part of an intimate national repertoire constitutive of Abkhazia’s postwar community.
Precise early Cambrian U–Pb zircon dates bracket the oldest trilobites and archaeocyaths in Moroccan West Gondwana
Authors: Landing Ed , Schmitz Mark D. , Geyer Gerd , Trayler Robin B. , Bowring Samuel A. 
Published: June 2020

AbstractNew U–Pb radioisotopic ages on early Cambrian volcanic zircons condition a high-resolution Bayesian age model that constrains the first occurrences and zonations of West Gondwanan archaeocyaths and trilobites in southern Morocco. The oldest archaeocyaths in the Tiout Member of the Igoudine Formation (519.71 + 0.26/− 0.35 Ma) are c. 6 Ma younger than the oldest Siberian archaeocyaths. The oldest Moroccan trilobite fragments, from the lower member of the Igoudine, are constrained to 519.95 + 0.43/− 0.40 Ma. The succeeding Issendalenian Stage (i.e. Hupetina antique – Eofallotaspis tioutensis – Fallotaspis plana – Choubertella – Daguinaspis trilobite zones) spans c. 1.5 Ma (519.78 + 0.26/− 0.37 Ma to 518.43 + 0.25/− 0.69 Ma). Identifiable Moroccan fallotaspidids and bigotinids, among Earth’s oldest trilobites, occur above a positive δ13C excursion dated with our age model at 520.27 + 0.59/− 0.57 Ma, and correlated with the IV excursion peak within the lower range of Siberian Atdabanian Stage trilobites (Repinaella Zone). This excursion is the best standard for a Cambrian Series 2 base. The oldest West Gondwana trilobite fragments are c. 1 Ma younger than those in Siberia and c. 0.5 Ma older than the oldest Avalonian trilobites (Callavia Zone). This diachrony means a trilobite first appearance datum is an inappropriate chronostratigraphic base for Cambrian Series 2. Taxonomic differences in the oldest trilobites between Cambrian palaeocontinents are in accordance with trace fossil evidence for the group’s appearance possibly as late as c. 530 Ma in the Cambrian Evolutionary Radiation. Coeval 519–517 Ma dates from Avalonia (cool-water siliciclastic shelf) and West Gondwana (tropical carbonate platform) sections with distinct macrofaunas emphasize these successions were latitudinally separate by the late Ediacaran Period.
Strategic sorting: the role of ordeals in health care
Authors: Zeckhauser Richard 
Published: June 2020

AbstractOrdeals are burdens placed on individuals that yield no benefits to others; hence they represent a dead-weight loss. Ordeals – the most common is waiting time – play a prominent role in rationing health care. The recipients most willing to bear them are those receiving the greatest benefit from scarce health-care resources. Health care is heavily subsidized; hence, moral hazard leads to excess use. Ordeals are intended to discourage expenditures yielding little benefit while simultaneously avoiding the undesired consequences of rationing methods such as quotas or pricing. This analysis diagnoses the economic underpinnings of ordeals. Subsidies for nursing-home care versus home care illustrate.
Eocene (46–44 Ma) Onset of Australia‐Pacific Plate Motion in the Southwest Pacific Inferred From Stratigraphy in New Caledonia and New Zealand
Authors: Dallanave Edoardo , Maurizot Pierre , Agnini Claudia , Sutherland Rupert , Hollis Christopher J. , Collot Julien , Dickens Gerald R. , Bachtadse Valerian , Strogen Dominic , Morgans Hugh E. G. 
Published: June 2020

AbstractThe Pacific plate circuit went through a complex reorganization during the early to middle Eocene, approximately coinciding with the onset of subduction along the western Pacific margin. However, the timing and dynamics of this change in the southwest Pacific and evolution of subduction beneath the Tonga‐Kermadec Arc are not fully resolved. We present magneto‐biostratigraphic data from an early to middle Eocene sedimentary section exposed in the Koumac‐Gomen area, New Caledonia, which is an emerged portion of the Norfolk Ridge. The 260 m‐thick succession contains a transition from pelagic micrite to terrigenous‐rich calciturbidite that is observed regionally in New Caledonia and which is interpreted to represent a shift from sedimentation on a stable submarine plateau to slope formation developed under a convergent tectonic regime. The stratigraphic contact between pelagic micrite and overlying calciturbidite is not exposed, but our magnetic polarity‐based chronology constrains the age of transition to 46–44 Ma, in agreement with the 45.3 Ma age recently obtained from the Noumea area in southern New Caledonia. We integrate records from New Caledonia with recent magnetostratigraphic data from South Island, New Zealand, where marked variations in terrigenous input occurred during the early and middle Eocene. Synchronous sedimentary changes in the southwest Pacific occurred at the same time as onset of rapid seafloor spreading south of Australia and New Zealand. We infer that the underlying cause of stratigraphic change was inception of slip at a new configuration of the Australia‐Pacific plate boundary, which evolved into the Tonga‐Kermadec subduction system.
Silica‐Rich Vein Formation in an Evolving Stress Field, Atlantis Bank Oceanic Core Complex
Authors: Ma Qiang , Dick Henry J. B. , Urann Benjamin , Zhou Huaiyang 
Published: June 2020

AbstractDrilling 809‐m Hole U1473A in the gabbro batholith at the Atlantis Bank Oceanic Core Complex (OCC) found two felsic vein generations: late magmatic fractionates, rich in deuteric water, hosted by oxide gabbros, and anatectic veins associated with dike intrusion and introduction of seawater‐derived volatiles. Microtextures show a change from compressional to tensional stress during vein formation. Temperatures and oxidation state were obtained from amphibole‐plagioclase and oxide pairs in the adjacent gabbros. Type I veins generally have reverse shear‐sense, with restricted ΔFMQ, high Mt/Ilm ratios, and low‐amphibole Cl/F indicating deuteric fluids. They formed during percolation and fractionation of Fe‐Ti‐rich melts into the primary olivine gabbro. Type II veins are usually hosted by olivine gabbro, occur at dike contacts and the margins of normal‐sense shear zones. They are undeformed or weakly deformed, with highly variable ΔFMQ, low Mt/Ilm ratios, and high‐amphibole Cl/F, indicating seawater‐derived fluids. The detachment fault on which the gabbro massif was emplaced rooted near the base of the dike‐gabbro transition beneath the rift valley. The ingress of seawater volatiles began at >800°C and penetrated at least ~590 m into the lower crust during extensional faulting in the rift valley and adjacent rift mountains. The sequence of the felsic vein formation likely reflects asymmetric diapiric flow, with a reversal of the stress regime, and a transition from juvenile to seawater‐derived volatiles. This, in turn, is consistent with fault capture leading to the large asymmetries in spreading rates during OCC formations and heat flow beneath the rift mountains.
Detection Limits and Near‐Field Ground Motions of Fast and Slow Earthquakes
Authors: Kwiatek Grzegorz , Ben‐Zion Yehuda 
Published: June 2020

AbstractWe investigate theoretical limits to detection of fast and slow seismic events, and spatial variations of ground motion expected from M 6 earthquakes at short epicentral distances. The analyses are based on synthetic velocity seismograms calculated with the discrete wavenumber method assuming seismic velocities and attenuation properties of the crust in Southern California. The examined source properties include different magnitudes (M −1.0 to M 6.0), static stress drops (0.1–10 MPa), and slow and fast ruptures (0.1–0.9 of shear wave velocity). For the M 6 events we also consider variations in rise times producing crack‐ and pulse‐type events and different rupture directivities. Slow events produce ground motion with considerably lower amplitude than corresponding regular fast earthquakes with the same magnitude, and hence are significantly more difficult to detect. The static stress drop and slip rise time also affect the maximum radiated seismic motion, and hence event detectability. Apart from geometrical factors, the saturation and depletion of seismic ground motion at short epicentral distances stem from radiation pattern, earthquake size (magnitude, stress drop), and rupture directivity. The rupture velocity, rise time, and directivity affect significantly the spatial pattern of the ground motions. The results can help optimizing detection of slow and fast small earthquakes and understand the spatial distribution of ground motion generated by large events.
Characteristics of Coastal Low‐Level Jets Over Beibu Gulf, China, During the Early Warm Season
Authors: Kong Hoiio , Zhang Qinghong , Du Yu , Zhang Fan 
Published: June 2020

AbstractWe investigated coastal low‐level jets (CLLJs) over Beibu Gulf, China, during the warm season (May to July) using hourly model simulations from a mesoscale weather research and forecasting model with a 9‐km horizontal resolution. Two high‐incidence CLLJ areas were identified over Beibu Gulf: one located on the leeward side of the Annamite Range that prevailed after sunset and the second off the northwestern coast of Hainan Island that reached its maximum intensity at midnight. The upstream wind of the Annamite Range was too weak to pass over the range during the daytime due to strong turbulent mixing near the land surface of Indochina; however, due to the suppression of the turbulent mixing after sunset, the flow intensified and crossed over the Annamite Range and further formed a hydraulic jump jet downstream. In addition to advection effect from upstream, topographic blocking effect of Hainan Island contributed to the CLLJ off the northwestern coast of Hainan Island, which persisted during the day but became more prevalent at midnight. Further momentum budget analysis and sensitivity experiments indicated that the upstream inertial oscillation due to the diurnal variation in turbulence over land was the primary source of the CLLJ over the ocean. These findings reveal the primary mechanism of CLLJs over Beibu Gulf, providing insight into CLLJ formation in other coastal regions with complex mountain ranges.
A Calibration Framework for High‐Resolution Hydrological Models Using a Multiresolution and Heterogeneous Strategy
Authors: Sun Ruochen , Hernández Felipe , Liang Xu , Yuan Huiling 
Published: June 2020

AbstractIncreasing spatial and temporal resolution of numerical models continues to propel progress in hydrological sciences, but, at the same time, it has strained the ability of modern automatic calibration methods to produce realistic model parameter combinations for these models. This paper presents a new reliable and fast automatic calibration framework to address this issue. In essence, the proposed framework, adopting a divide and conquer strategy, first partitions the parameters into groups of different resolutions based on their sensitivity or importance, in which the most sensitive parameters are prioritized with the highest resolution in the parameter search space, while the least sensitive ones are initially explored with the coarsest resolution. This is followed by an optimization‐based iterative calibration procedure consisting of a series of subtasks or runs. Between consecutive runs, the setup configuration is heterogeneous with parameter search ranges and resolutions varying among groups. At the completion of each subtask, the parameter ranges within each group are systematically refined from their previously estimated ranges, which are initially based on a priori information. Parameters attain stable convergence progressively with each run. A comparison of this new calibration framework with a traditional optimization‐based approach was performed using a quasi‐synthetic double‐model setup experiment to calibrate 134 parameters and two well‐known distributed hydrological models: the Variable Infiltration Capacity (VIC) model and the Distributed Hydrology Soil Vegetation Model (DHSVM). The results demonstrate statistically that the proposed framework can better mitigate equifinality problem, yields more realistic model parameter estimates, and is computationally more efficient.
Bayesian Calibration and Validation of a Large‐Scale and Time‐Demanding Sediment Transport Model
Authors: Beckers Felix , Heredia Andrés , Noack Markus , Nowak Wolfgang , Wieprecht Silke , Oladyshkin Sergey 
Published: June 2020

AbstractThis study suggests a stochastic Bayesian approach for calibrating and validating morphodynamic sediment transport models and for quantifying parametric uncertainties in order to alleviate limitations of conventional (manual, deterministic) calibration procedures. The applicability of our method is shown for a large‐scale (11.0 km) and time‐demanding (9.14 hr for the period 2002–2013) 2‐D morphodynamic sediment transport model of the Lower River Salzach and for three most sensitive input parameters (critical Shields parameter, grain roughness, and grain size distribution). Since Bayesian methods require a significant number of simulation runs, this work proposes to construct a surrogate model, here with the arbitrary polynomial chaos technique. The surrogate model is constructed from a limited set of runs (n=20) of the full complex sediment transport model. Then, Monte Carlo‐based techniques for Bayesian calibration are used with the surrogate model (105 realizations in 4 hr). The results demonstrate that following Bayesian principles and iterative Bayesian updating of the surrogate model (10 iterations) enables to identify the most probable ranges of the three calibration parameters. Model verification based on the maximum a posteriori parameter combination indicates that the surrogate model accurately replicates the morphodynamic behavior of the sediment transport model for both calibration (RMSE = 0.31 m) and validation (RMSE = 0.42 m). Furthermore, it is shown that the surrogate model is highly effective in lowering the total computational time for Bayesian calibration, validation, and uncertainty analysis. As a whole, this provides more realistic calibration and validation of morphodynamic sediment transport models with quantified uncertainty in less time compared to conventional calibration procedures.
Twenty Lessons Drawn From My Subsurface Hydrology Career
Authors: Neuman Shlomo P. 
Published: June 2020

AbstractThis personal perspective complements a Brief Autobiography I (Figure 1) wrote for the journal Ground Water (Neuman, 2008). Whereas there I described my personal life from early childhood to my career stage at the time, here I focus on key science lessons my academic research, teaching, and professional consulting have taught me. Though many of these lessons have been shared with students and colleagues throughout my career, never have I had the opportunity to collect and summarize them for a wider audience as I do here. I thank the Editors for the opportunity to do so, Professor Emeritus Steve Burgess of the University of Washington and Professor Alberto Guadagnini of the Politecnico di Milano, Italy, for helping me to do so better, and hope readers will find some of these lessons intriguing enough to explore and develop the related ideas further.
Evaluating Spatiotemporal Resolution of Trace Element Concentrations and Pb Isotopic Compositions of Honeybees and Hive Products as Biomonitors for Urban Metal Distribution
Authors: Smith Kate E. , Weis Dominique 
Published: June 2020

AbstractAssessing metal distributions in cities is an important aspect of urban environmental quality management. Western honeybees (Apis mellifera) and their products are biomonitors that can elucidate small‐scale metal distribution within a city. We compare range and variations in trace element (TE) concentrations and lead (Pb) isotopic compositions of honey, bee tissue, bee pollen, and propolis collected throughout Metro Vancouver (BC, Canada). Honey, bee, and bee pollen results have similar TE and isotopic trends; samples collected in urban and industrialized areas exhibit elevated concentrations of anthropogenically influenced TE (e.g., Pb, Zn, V, and Ti) and a less radiogenic Pb isotopic composition (i.e., lower 206Pb/207Pb and elevated 208Pb/206Pb) relative to their suburban and rural counterparts. For example, 206Pb/207Pb, 208Pb/206Pb in honey range from 1.126, 2.131 and 1.184, 2.063; extremes measured in honey from urban and suburban/rural areas, respectively. Except for propolis, measured and interpolated (kriged) results in all materials reflect the immediate zoning or land use setting near the hive, providing kilometer‐scale geospatial resolution, suitable for monitoring urban systems. Statistical analysis reveals that no systematic variations or intra‐ or inter‐annual trends exist in TE concentrations or Pb isotopic compositions, including among sampling and field methods (i.e., old vs. new hive equipment and honey from the brood nest box vs. honey super). The results of this systematic study using honeybees and hive products in Metro Vancouver provide a robust, current baseline for future comparison of local land use and environmental policy change.
Spatial Distributions of Nitric Oxide in the Antarctic Wintertime Middle Atmosphere During Geomagnetic Storms
Authors: Newnham D. A. , Rodger C. J. , Marsh D. R. , Hervig M. E. , Clilverd M. A. 
Published: June 2020

AbstractEnergetic electron precipitation leads to increased nitric oxide (NO) production in the mesosphere and lower thermosphere. NO distributions in the wintertime, high‐latitude Southern Hemisphere atmosphere during geomagnetic storms are investigated. NO partial columns in the upper mesosphere at altitudes 70–90 km and in the lower thermosphere at 90–110 km have been derived from observations made by the Solar Occultation For Ice Experiment (SOFIE) on board the Aeronomy of Ice in the Mesosphere (AIM) satellite. The SOFIE NO measurements during 17 geomagnetic storms in 2008–2014 have been binned into selected geomagnetic latitude and geographic latitude/longitude ranges. The regions above Antarctica showing the largest instantaneous NO increases coincide with high fluxes of 30–300 keV precipitating electrons from measurements by the second‐generation Space Environment Monitor (SEM‐2) Medium Energy Proton and Electron Detector (MEPED) instrument on the Polar‐orbiting Operational Environmental Satellites (POES). Significant NO increases over the Antarctic Peninsula are likely due to precipitation of >30 keV electrons from the radiation belt slot region. NO transport is estimated using Horizontal Wind Model (HWM14) calculations. In the upper mesosphere strong eastward winds (daily mean zonal wind speed ~20–30 m s−1 at 80 km) during winter transport NO‐enriched air away from source regions 1–3 days following the storms. Mesospheric winds also introduce NO‐poor air into the source regions, quenching initial NO increases. Higher up, in the lower thermosphere, weaker eastward winds (~5–10 m s−1 at 100 km) are less effective at redistributing NO zonally.