bluuebunny/crossref_metadata_2025_split huggingface dataset:
P Wave Anisotropic Tomography of the SE Tibetan Plateau: Evidence for the Crustal and Upper‐Mantle Deformations
Authors: Huang Zhouchuan , Wang Liangshu , Xu Mingjie , Zhao Dapeng 
Published: October 2018

AbstractThe upper crust in the SE Tibetan Plateau is rotating around the eastern Himalayan syntax clockwise, and the western margin of the Yangtze Craton has been involved in the active tectonics. However, it is still unclear whether and how the deep crust and upper mantle respond to the plateau expansion. In this study we present a high‐resolution three‐dimensional model of P wave velocity tomography and azimuthal anisotropy in the crust and uppermost mantle beneath the SE Tibetan Plateau determined using traveltime data recorded by a dense seismic network. Widespread low‐velocity zones are revealed around a high‐velocity body in the deep crust and uppermost mantle beneath the southwest Yangtze Craton, where fast‐velocity directions of the azimuthal anisotropy are mostly parallel to the contour lines of the surface topography and the Moho depth along the plateau margin. These results indicate that gravitational potential plays an important role in the crustal and uppermost‐mantle deformations in the SE Tibetan Plateau. Meanwhile, the shallow crust may drop down to the deep crust and drive the ductile deep‐crustal material to intrude into the adjacent regions. The extruded crust is trapped in a deep‐crustal corner and obstructed by the surrounding strong blocks. The trapped crustal material may rise up, causing significant uplift and high heat flow at the surface.
Constraints on Rift Basin Structure and Border Fault Growth in the Northern Malawi Rift From 3‐D Seismic Refraction Imaging
Authors: Accardo N. J. , Shillington D. J. , Gaherty J. B. , Scholz C. A. , Nyblade A. A. , Chindandali P. R. N. , Kamihanda G. , McCartney T. , Wood D. , Wambura Ferdinand R. 
Published: October 2018

AbstractWe present new constraints on rift basin structure in the northern Malawi Rift from a 3‐D compressional velocity model to investigate border fault geometry, accommodation zone structure, and the role of preexisting structures underpinning this rift system. The velocity model uses observations from the first wide‐angle refraction study conducted using lake‐bottom seismometers in one of the East African great lakes. The Malawi Rift is flanked by basin‐bounding border faults and crosses several significant remnant structures, making it an ideal location to investigate the development of normal faults and their associated basins. The 3‐D velocity model reveals up to ~5 km of synrift sediments, which smoothly transition from eastward thickening against the Livingstone Fault in the North Basin to westward thickening against the Usisya Fault in the Central Basin. Greater than 4 km of sediment are imaged within the accommodation zone pointing to the early development of the border faults. We use new constraints on synrift sediment thickness to construct displacement profiles for both faults. Both faults accommodate large throws (>7 km) consistent with their significant lengths. The dimensions of these faults are close to or larger than the maximum size predicted by models of fault growth. The presence of an intermediate velocity unit with velocities of 3.75–4.5 km/s is interpreted to represent sediment deposits beneath Lake Malawi from prior rifting in the Permo‐Triassic (Karoo) and/or Cretaceous‐Paleogene. The distribution of preexisting basins implied by these sediments may help account for changes in intrabasinal faulting and border fault development between the two basins.
Spectral Reflectance of Powder Coatings on Carbonaceous Chondrite Slabs: Implications for Asteroid Regolith Observations
Authors: Kiddell C. B. , Cloutis E. A. , Dagdick B. R. , Stromberg J. M. , Applin D. M. , Mann J. P. 
Published: October 2018

AbstractCarbonaceous chondrite meteorites (CCs) are among the most primitive materials in the solar system and provide important insights into solar system history and evolution. A number of planetary spacecraft missions will visit asteroids that are thought to compositionally resemble these meteorites. To better assist sample acquisition in terms of how the physical properties of CCs affect their reflectance spectra, we investigated the spectral reflectance properties of solid and powdered CCs and powder coatings on slabs of a number of CCs, including CB, CH, CK, CM, CO, CR, and CV classes. We found that decreasing grain size leads to increasing reflectance across the ~500‐ to 2,500‐nm range and steeper spectral slope, regardless of CC type. Powdered CC reflectance spectra are brighter beyond ~500 nm and redder than bare roughened slabs. For powders sprinkled on slabs, as the powder coating gets thicker, spectral slopes get redder. Optically thick fine‐grained powders are brighter beyond ~500 nm and are as red or redder than slabs covered with airfall dust (for dust thicknesses up to a few hundred microns). Diagnostic absorption features of CC minerals, particularly those in the 1,000‐nm region attributable to Fe‐bearing silicates, are ubiquitous regardless of physical properties. Reflectance spectra of terrestrially weathered (i.e., rusty) CCs are strongly modified below ~700 nm and in the 900‐ and 1,900‐nm regions by these Fe oxyhydroxides. Their effects can be mitigated through chemical treatment, but this may also affect preterrestrial ferric iron‐bearing phases. Some spectral characteristics, such as hydrous and anhydrous silicate absorption bands in CC spectra, are present regardless of physical properties (fine‐grained dust, powders, slabs, and dust on slabs). Other spectral characteristics (such as albedo and spectral slope) vary as a function of physical properties, indicating that reflectance spectroscopy could be used to ascribe spectral variations across an asteroid's surface to either physical or compositional causes. This information can, in turn, be used to inform site selection for asteroid sample return missions, where both composition and physical properties are important drivers. When searching for fine‐grained areas on an asteroid to sample, the best indication would be the brightest‐ and reddest‐sloped spectra.
Characterizing the Radiative Effect of Rain Using a Global Ensemble of Cloud Resolving Simulations
Authors: Hill P. G. , Chiu J. C. , Allan R. P. , Chern J.‐D. 
Published: October 2018

AbstractThe effect of rain on radiative fluxes and heating rates is a process that is neglected in most of the large scale atmospheric models used for weather forecasting or climate prediction. Yet to our knowledge, the magnitude of the resulting radiative bias remains unquantified. This study aims to quantify the rain radiative effect (RRE) at a range of temporal and spatial scales, as a step toward determining whether the radiation schemes in these models should include rain. Using off‐line radiative transfer calculations with input from an ensemble of cloud resolving model simulations, we find that rain has a negligible effect on global mean radiative fluxes (less than 0.2 W m−2). Weekly mean RREs at specific locations may be larger (less than 4 W m−2). At the finest temporal and spatial resolutions, the RRE can occasionally be much larger again (greater than 100 W m−2), but values exceeding 10 W m−2 occur in less than 0.1% of cases. Using detailed analysis of case studies we demonstrate that the magnitude and direction of the RRE depend on the rain water path, its vertical location with respect to cloud, and, for longwave radiation, the temperature at which it occurs. Large RREs generally only occur when the rain water path is large and the cloud water path is small. These cases are infrequent and intermittent. As the RREs are generally small, we conclude that this missing process is unlikely to be important for large scale atmospheric models.
PRYSM v2.0: A Proxy System Model for Lacustrine Archives
Authors: Dee Sylvia G. , Russell James M. , Morrill Carrie , Chen Zihan , Neary Ashling 
Published: October 2018

AbstractReconstructions of temperature and hydrology from lake sedimentary archives have made fundamental contributions to our understanding of past, present, and future climate and help evaluate general circulation models (GCMs). However, because paleoclimate observations are an indirect (proxy) constraint on climatic variables, confounding effects of proxy processes complicate interpretations of these archives. To circumvent these uncertainties inherent to paleoclimate data‐model comparison, proxy system models (PSMs) provide transfer functions between climate variables and the proxy. We here present a new PSM for lacustrine sedimentary archives. The model simulates lake energy and water balance, sensors including leaf wax δD and carbonate δ18O, bioturbation, and compaction of sediment to lend insight toward how these processes affect and potentially obfuscate the original climate signal. The final product integrates existing and new models to yield a comprehensive, modular, adaptable, and publicly available PSM for lake systems. Highlighting applications of the PSM, we forward model lake variables with GCM simulations of the last glacial maximum and the modern. The simulations are evaluated with a focus on sensitivity of lake surface temperature and mixing to climate forcing, using Lakes Tanganyika and Malawi as case studies. The PSM highlights the importance of mixing on interpretations of air temperature reconstructions from lake archives and demonstrates how changes in mixing depth alone may induce nonstationarity between in situ lake and air temperatures. By placing GCM output in the same reference frame as lake paleoclimate archives, we aim to improve interpretations of past changes in terrestrial temperatures and water cycling.
Depositional Evolution of the Western Amundsen Basin, Arctic Ocean: Paleoceanographic and Tectonic Implications
Authors: Castro Carlos F. , Knutz Paul C. , Hopper John R. , Funck Thomas 
Published: October 2018

AbstractA new stratigraphic model and estimated sedimentation rates of the western Amundsen Basin, Arctic Ocean, are presented based on multichannel seismic reflection data, seismic refraction data, magnetic data, and integrated with the sedimentary sequence from the central Arctic Ocean, obtained during the Arctic Coring Expedition. This places new constraints on the postbreakup Cenozoic depositional history of the basin, the adjacent Lomonosov Ridge, and improves the understanding of the tectonic, climatic, and oceanographic conditions in the central Arctic region. Four distinct phases of basin development are proposed. During the Paleocene‐mid‐Oligocene, high sedimentation rates are linked to terrestrial input and increased pelagic deposition in a restricted basin. Deposition of sedimentary wedges and mass transport into marginal depocenters reflect a period of tectonic instability linked to compression associated with the Eurekan Orogeny in the Arctic. During the late Oligocene‐early Miocene, widespread passive infill associated with hemipelagic deposition reflects a phase of limited tectonism, most likely in a freshwater estuarine setting. During the middle Miocene, mounded sedimentary buildups along the Lomonosov Ridge suggest the onset of geostrophic bottom currents that likely formed in response to a deepening and widening of the Fram Strait beginning around 18 Ma. In contrast, the Plio‐Pleistocene stage is characterized by erosional features such as scarps and channels adjacent to levee accumulations, indicative of a change to a higher‐energy environment. These deposits are suggested to be partly associated with dense shelf water‐mass plumes driven by supercooling and brine formation over the northern Greenland continental shelf.
Urban Residential Surface and Subsurface Hydrology: Synergistic Effects of Low‐Impact Features at the Parcel Scale
Authors: Voter C. B. , Loheide S. P. 
Published: October 2018

AbstractAccurately predicting the hydrologic effects of urbanization requires an understanding of how hydrologic processes are affected by low‐impact development practices. In this study, we explored how growing season surface runoff, deep drainage, and evapotranspiration on a residential parcel are affected by several low‐impact interventions, including three “impervious‐centric” interventions (disconnecting downspouts, disconnecting sidewalks, and adding a transverse slope to the driveway and front walk), two “pervious‐centric” interventions (decompacting soil and adding microtopography), and all possible “holistic” combinations. Results were compared to both a highly and moderately compacted baseline parcel under an average and a dry weather scenario for a temperate climate. We find that under reasonable assumptions for highly compacted soil, pervious areas are a major source of runoff and disconnecting impervious surfaces may be relatively less effective without improving soil conditions. Under both highly and moderately compacted soil conditions, combining efforts to decompact soil with impervious disconnection has a synergistic effect on reducing surface runoff and increasing deep drainage and evapotranspiration. All combinations of interventions enhance infiltration, but the partitioning of additional root zone water between deep drainage and evapotranspiration depends on the weather scenario. Importantly, when all low‐impact interventions are applied together, growing season deep drainage is higher than that from a vacant lot with no impervious surfaces. We infer that ecohydrologic interfaces between impervious and pervious areas are strong controls on urban hydrologic fluxes and that high‐resolution, process‐based models can be used to account for these interfaces and thereby improve predictions of the hydrologic effects of low‐impact interventions.
A Thermally Stratified Reservoir Module for Large‐Scale Distributed Stream Temperature Models With Application in the Tennessee River Basin
Authors: Niemeyer Ryan J. , Cheng Yifan , Mao Yixin , Yearsley John R. , Nijssen Bart 
Published: October 2018

AbstractRiver temperatures affect water quality, power plant cooling, and freshwater ecosystems. Stream temperature models that treat river reaches and reservoirs as well‐mixed segments do not capture thermal stratification in reservoirs. To account for the effects of reservoir stratification on downstream water temperatures, we developed a two‐layer stratified reservoir module, which was integrated into the River Basin Model (RBM) to simulate river temperature across a river network with multiple large thermally stratified reservoirs. To evaluate the performance of this model configuration compared to RBM without thermally stratified reservoirs, we simulated river temperature in the Tennessee River Basin in the southeastern United States. We simulated land surface hydrologic fluxes using the Variable Infiltration Capacity (VIC) model and routed runoff using the river routing model RVIC. The two‐layer model configuration reduced the bias in simulated summer river temperature from 6.7 to −1.2 °C downstream of a reservoir with a residence time of 92 days and from 3.0 to −0.7 °C downstream of a reservoir with a residence time of 8 days. Improvement in fall and winter, when reservoirs tend to be well mixed, is minimal. RBM with the two‐layer module also captured the observed longitudinal river temperature variation downstream of a reservoir, with cool temperatures immediately downstream of the reservoir and gradual warming of the river as it flows downstream. Incorporating a simple stratified reservoir module into RBM improves model performance and increases the ability to apply the river temperature model to large basins with multiple large reservoirs.
Kinetic Interface Sensitive Tracers: Experimental Validation in a Two‐Phase Flow Column Experiment. A Proof of Concept
Authors: Tatomir A. , De Vriendt K. , Zhou D. , Gao H. , Duschl F. , Sun F. , Licha T. , Sauter M. 
Published: October 2018

AbstractThe quantification of the interfacial area between fluids in a multiphase system in porous media has been a subject of growing interest in disciplines where mass transfer across fluid interfaces is of importance. In this study, a proof of concept for a novel kinetic interface sensitive (KIS) tracer is provided by employing a simple, low‐cost, well‐controlled dynamic column experiment in conjunction with a macroscale two‐phase flow reactive transport model. The steel column is filled with a well‐characterized porous medium consisting of well‐sorted normally distributed glass beads (d50 = 240 μm). KIS tracers were designed to determine the specific interfacial area, awn, between a nonwetting fluid and a wetting fluid, by evaluating the chemical reaction rates and mass transfer across the fluid‐fluid interface. This study shows for the first time a general framework behind the use of KIS tracers and their potential in assessing the awn for a known capillary pressure‐saturation relationship under laboratory conditions. A two‐phase flow four‐component reactive transport and a two‐phase flow two‐component transport numerical model were developed to simulate the oil flooding of the initially water saturated column and tracer breakthrough curves obtained from experimental data. These breakthrough curves were subsequently used to approximate awn using a polynomial relationship. The interpretation of the KIS tracer column experiments indicates that the range for maximum value of awn is between 500 and 540 m2/m3. The results also show that despite the use of two independently synthesized tracers, if the reaction kinetics are well quantified, similar awn values can be obtained.
Geochemical Exports to River From the Intrameander Hyporheic Zone Under Transient Hydrologic Conditions: East River Mountainous Watershed, Colorado
Authors: Dwivedi Dipankar , Steefel Carl I. , Arora Bhavna , Newcomer Michelle , Moulton J. David , Dafflon Baptiste , Faybishenko Boris , Fox Patricia , Nico Peter , Spycher Nicolas , Carroll Rosemary , Williams Kenneth H. 
Published: October 2018

AbstractTo understand how redox processes influence carbon, nitrogen, and iron cycling within the intrameander hyporheic zone, we developed a biotic and abiotic reaction network and incorporated it into the reactive transport simulator PFLOTRAN. Two‐dimensional reactive flow and transport simulations were performed (1) to evaluate how transient hydrological conditions control the lateral redox zonation within an intrameander region of the East River in Colorado and (2) to quantify the impact of a single meander on subsurface exports of carbon and other geochemical species to the river. The meander's overall contribution to the river was quantified by integrating geochemical outfluxes along the outside of the meander bend. The model was able to capture the field‐observed trends of dissolved oxygen, nitrate, iron, pH, and total inorganic carbon along a 2‐D transect. Consistent with field observations, simulated dissolved oxygen and nitrate decreased along the intrameander flow paths while iron (Fe2+) concentration increased. The simulation results further demonstrated that the reductive potential of the lateral redox zonation was controlled by groundwater velocities resulting from river stage fluctuations, with low‐water conditions promoting reducing conditions. The sensitivity analysis results showed that permeability had a more significant impact on biogeochemical zonation compared to the reaction pathways under transient hydrologic conditions. The simulation results further indicated that the meander acted as a sink for organic and inorganic carbon as well as iron during the extended baseflow and high‐water conditions; however, these geochemical species were released into the river during the falling limb of the hydrograph.
Matched-Pair Analysis of Local Infiltration Analgesia in Total Knee Arthroplasty: Patient Satisfaction and Perioperative Pain Management in 846 Cases
Authors: Greimel Felix , Maderbacher Günther , Baier Clemens , Schwarz Timo , Zeman Florian , Meissner Winfried , Grifka Joachim , Benditz Achim 
Published: October 2018

AbstractIn the recent past, numerous studies evaluating local infiltration analgesia (LIA) with controversial results have been reported. Efforts have been made to improve patients' outcome regarding operation techniques and material, as well as pain management and anesthetic methods. In this study, postoperative pain management and patient satisfaction were evaluated in patients undergoing total knee replacement surgery with or without intraoperative LIA. Within the context of the “Quality Improvement in Postoperative Pain Management” (QUIPS) project, parameters were collected on the first postoperative day. All patients included in this study underwent primary knee replacement surgery with general anesthesia. Parameters were compared after performing a 1:1 matched-pair analysis within 14 orthopaedic departments. Pain levels and pain management satisfaction were measured using the numerous rating scales, and pain medication use was compared. From 2010 to 2015, 2,789 patients who underwent primary knee arthroplasty with general anesthesia were evaluated within the project, of whom a total of 846 patients could be compared after performing a matched-pair analysis. Pain scores were significantly better in the LIA group (p = 0.019 for activity pain, p = 0.043 for maximum pain, p < 0.001 for minimum pain), but pain management satisfaction was not superior (p = 0.083). Patients with LIA required less opioids in the recovery room (p = 0.048), while nonopioid medication did not differ significantly (p = 0.603). At the ward, 24 hours postoperatively, no significant difference in the use for nonopioids (p = 0.789) could be measured, whereas patients in the LIA group received significantly more opioids (p < 0.001). Although LIA achieved improvement in pain score outcome, and a comparable patient satisfaction level in the immediate postoperative course, the use of LIA in knee arthroplasty, controversially discussed in the current literature, was not able to reduce the need for opioid pain medication in this study.
Cueing Refrains in the Medieval Conductus
Authors: Caldwell Mary Channen 
Published: October 2018

AbstractAs lyrical refrain forms flourished beginning in the twelfth century and increased attention was paid to the mise en page of song in manuscript sources, scribes faced the dilemma of how to cue frequent repetition of poetry and music. Owing to a lack of shared conventions among these scribes, the signalling of repetition varied greatly among sources, the resulting inconsistencies furnishing what Ardis Butterfield calls ‘glimpses of scribal thinking’. Nowhere is this more evident than in approaches to notating the Latin refrain, a structural feature in a range of genres and an inexact yet related parallel to the French refrain. I argue in this article that the graphic treatment of refrains in Latin song exposes assumptions that both scribes and performers made about form, genre and the realization of song in performance. Attending to the visual cueing of refrains clarifies textual and musical ambiguities arising from the simultaneously oral, written and performative milieu within which Latin song was cultivated and disseminated.