bluuebunny/crossref_metadata_2025_split huggingface dataset:
A model intercomparison of the tropical precipitation response to a CO2 doubling in aquaplanet simulations
Authors: Seo Jeongbin , Kang Sarah M. , Merlis Timothy M. 
Published: December 2016

AbstractIn the present‐day climate, the mean Intertropical Convergence Zone (ITCZ) is north of the equator. We investigate changes in the ITCZ latitude under global warming, using multiple atmospheric models coupled to an aquaplanet slab ocean. The reference climate, with a warmer north from prescribed ocean heating, is perturbed by doubling CO2. Most models exhibit a northward ITCZ shift, but the shift cannot be accounted for by the response of energy flux equator where the atmospheric energy transport (FA) vanishes. The energetics of the simulated circulation shifts are subtle: changes in the efficiency with which the Hadley circulation transports energy, the total gross moist stability (Δm), dominate over mass flux changes in determining δFA. Even when δFA ≈ 0, the ITCZ can shift significantly due to changes in Δm, which have often been neglected previously. The dependence of ITCZ responses on δΔm calls for improved understanding of the physics determining the tropical Δm.
The latitudinal structure of nighttime ionospheric TEC and its empirical orthogonal functions model over North American sector
Authors: Le Huijun , Yang Na , Liu Libo , Chen Yiding , Zhang Hui 
Published: December 2016

AbstractWe collected total electron content (TEC) data in the longitudinal sector of 60°W–90°W during 1999–2015 to investigate the latitudinal variation of nighttime middle‐ and high‐latitude ionosphere. The midlatitude trough is one of the important features of the nighttime ionosphere. The statistical analysis provides unprecedented detail of the local time, seasonal, solar activity, and geomagnetic activity variations of the total electron content in the latitude range of 40°N–75°N, focusing on the variation of midlatitude trough. The results show that the trough minimum position has significant local time, seasonal, and geomagnetic activity dependences but slight solar activity dependence. In addition, an empirical model of the TEC in the middle to high latitudes was constructed by empirical orthogonal function analysis. The empirical model can reconstruct latitudinal profiles of TEC and well reproduce the dependence of the midlatitude trough on local time, seasonal, solar cycle, and geomagnetic activity. In addition, we also analyzed the geomagnetic activity dependence of TEC at different latitudes and different local time sectors.
Deep structure of the Lofoten‐Vesterålen segment of the Mid‐Norwegian continental margin and adjacent areas derived from 3‐D density modeling
Authors: Maystrenko Y. P. , Olesen O. , Gernigon L. , Gradmann S. 
Published: December 2016

AbstractTo understand the major structural features of the sedimentary cover and crystalline crust of the Lofoten‐Vesterålen margin and the northern part of the Vøring segment of the Mid‐Norwegian continental margin, a lithosphere‐scale 3‐D structural model has been constructed. This model extends from the exposed crystalline rocks of the Fennoscandian Shield in the east to the Cenozoic oceanic domain of the Norwegian‐Greenland Sea in the west, covering the Vestfjorden, Ribban, and Røst Basins and the northern parts of the Vøring Basin and Trøndelag Platform. All available published and/or released data have been used to set the initial 3‐D model which has been validated by means of 3‐D density forward modeling to obtain a gravity‐consistent 3‐D structural/density model. Results from the 3‐D density modeling reveal that relatively thick sedimentary rocks are present in the distal Røst Basin below the lava flows. The presence of a low‐density more than 20 km thick granitic body has been modeled within the middle‐upper crystalline crust beneath the eastern part of the Vestfjorden Basin and the adjacent mainland. Moreover, the results of the 3‐D density modeling indicate the presence of an atypical low‐density lithospheric mantle beneath a large part of the Lofoten‐Vesterålen margin which is required to fit the regional component of the modeled gravity with the observed one. The pronounced crustal feature within the model area is the Bivrost Lineament that appears to be the deeply seated lithosphere‐scale boundary that delineates clearly the Lofoten‐Vesterålen segment from the Vøring margin showing contrasting densities and crustal thicknesses.
Inelastic deformation during sill and laccolith emplacement: Insights from an analytic elastoplastic model
Authors: Scheibert J. , Galland O. , Hafver A. 
Published: December 2016

AbstractNumerous geological observations evidence that inelastic deformation occurs during sills and laccoliths emplacement. However, most models of sill and laccolith emplacement neglect inelastic processes by assuming purely elastic deformation of the host rock. This assumption has never been tested so that the role of inelastic deformation on the growth dynamics of magma intrusions remains poorly understood. In this paper, we introduce the first analytical model of shallow sill and laccolith emplacement that accounts for elastoplastic deformation of the host rock. It considers the intrusion's overburden as a thin elastic bending plate attached to an elastic‐perfectly plastic foundation. We find that, for geologically realistic values of the model parameters, the horizontal extent of the plastic zone lp is much smaller than the radius of the intrusion a. By modeling the quasi‐static growth of a sill, we find that the ratio lp/a decreases during propagation, as
, with ΔP the magma overpressure. The model also shows that the extent of the plastic zone decreases with the intrusion's depth, while it increases if the host rock is weaker. Comparison between our elastoplastic model and existing purely elastic models shows that plasticity can have a significant effect on intrusion propagation dynamics, with, e.g., up to a doubling of the overpressure necessary for the sill to grow. Our results suggest that plasticity effects might be small for large sills but conversely that they might be substantial for early sill propagation.
Empty substrate integrated waveguide technology for E plane high‐frequency and high‐performance circuits
Authors: Belenguer Angel , Cano Juan Luis , Esteban Héctor , Artal Eduardo , Boria Vicente E. 
Published: January 2017

AbstractSubstrate integrated circuits (SIC) have attracted much attention in the last years because of their great potential of low cost, easy manufacturing, integration in a circuit board, and higher‐quality factor than planar circuits. A first suite of SIC where the waves propagate through dielectric have been first developed, based on the well‐known substrate integrated waveguide (SIW) and related technological implementations. One step further has been made with a new suite of empty substrate integrated waveguides, where the waves propagate through air, thus reducing the associated losses. This is the case of the empty substrate integrated waveguide (ESIW) or the air‐filled substrate integrated waveguide (air‐filled SIW). However, all these SIC are H plane structures, so classical H plane solutions in rectangular waveguides have already been mapped to most of these new SIC. In this paper a novel E plane empty substrate integrated waveguide (ESIW‐E) is presented. This structure allows to easily map classical E plane solutions in rectangular waveguide to this new substrate integrated solution. It is similar to the ESIW, although more layers are needed to build the structure. A wideband transition (covering the frequency range between 33 GHz and 50 GHz) from microstrip to ESIW‐E is designed and manufactured. Measurements are successfully compared with simulation, proving the validity of this new SIC. A broadband high‐frequency phase shifter (for operation from 35 GHz to 47 GHz) is successfully implemented in ESIW‐E, thus proving the good performance of this new SIC in a practical application.
Approximate solutions for diffusive fracture‐matrix transfer: Application to storage of dissolved CO2 in fractured rocks
Authors: Zhou Quanlin , Oldenburg Curtis M. , Spangler Lee H. , Birkholzer Jens T. 
Published: January 2017

AbstractAnalytical solutions with infinite exponential series are available to calculate the rate of diffusive transfer between low‐permeability blocks and high‐permeability zones in the subsurface. Truncation of these series is often employed by neglecting the early‐time regime. In this paper, we present unified‐form approximate solutions in which the early‐time and the late‐time solutions are continuous at a switchover time. The early‐time solutions are based on three‐term polynomial functions in terms of square root of dimensionless time, with the first coefficient dependent only on the dimensionless area‐to‐volume ratio. The last two coefficients are either determined analytically for isotropic blocks (e.g., spheres and slabs) or obtained by fitting the exact solutions, and they solely depend on the aspect ratios for rectangular columns and parallelepipeds. For the late‐time solutions, only the leading exponential term is needed for isotropic blocks, while a few additional exponential terms are needed for highly anisotropic rectangular blocks. The optimal switchover time is between 0.157 and 0.229, with highest relative approximation error less than 0.2%. The solutions are used to demonstrate the storage of dissolved CO2 in fractured reservoirs with low‐permeability matrix blocks of single and multiple shapes and sizes. These approximate solutions are building blocks for development of analytical and numerical tools for hydraulic, solute, and thermal diffusion processes in low‐permeability matrix blocks.
Emergency Medicine Faculty Are Poor at Predicting Burnout in Individual Trainees: An Exploratory Study
Authors: Lu Dave W. , Lank Patrick M. , Branzetti Jeremy B. 
Published: December 2016

AbstractObjectiveBurnout is common among emergency medicine (EM) physicians, and it is prevalent even among EM trainees. Recently proposed Accreditation Council for Graduate Medical Education requirements encourage faculty to alert residency leadership when trainees display signs of burnout. It remains uncertain how trainees experiencing burnout can be reliably identified. We examined if EM faculty advisers at one institution can accurately predict burnout in their EM resident advisees.MethodsIn this cross‐sectional, exploratory study at a single institution, we measured EM trainee burnout using the Maslach Burnout Inventory through a confidential, electronic survey. We subsequently asked EM faculty to predict if their designated advisees were experiencing burnout through a separate confidential, electronic survey. Burnout results were dichotomized from each survey and compared using a 2 × 2 contingency table and Fisher's exact test.ResultsThirty‐six of 54 (66.7%) eligible EM trainees completed the burnout assessment. Eleven of 19 (57.9%) eligible faculty advisers completed trainee burnout predictions, resulting in 30 of 54 (55.6%) trainees who completed the burnout assessment and had a faculty burnout prediction. Trainees reported an overall burnout rate of 70.0% (95% confidence interval [CI] = 53.6% to 86.4%). Cumulative faculty predictions of trainee burnout resulted in an overall burnout rate of 16.7% (95% CI = –5.3% to 38.7%). The sensitivity and specificity of faculty predictions of trainee burnout were 19.1% (95% CI = 5.5% to 41.9%) and 88.9% (95% CI = 51.8% to 99.7%), respectively. Faculty prediction of trainee burnout had a positive predictive value of 80.0% (95% CI = 28.4% to 99.5%) and a negative predictive value of 32.0% (95% CI = 15.0% to 53.5). The difference between trainees’ reported rate of burnout and faculty predictions of trainee burnout was significant (p < 0.001).ConclusionEmergency medicine faculty prediction of trainee burnout was poor. Education on recognizing burnout and other methods of identifying trainee burnout may be necessary.
Self‐crosslinkable epoxidized natural rubber–silica hybrids
Authors: Xu Tiwen , Jia Zhixin , Wang Song , Chen Yongjun , Luo Yuanfang , Jia Demin , Peng Zheng 
Published: December 2016

ABSTRACTEpoxidized natural rubber (ENR)–silica hybrids without any other additives were prepared by an open‐mill mixing method at room temperature. The curing characteristics, crosslinking density, mechanical properties, and dynamical mechanical properties were investigated. The results indicate that the ENR–silica hybrid materials could be cured with silica as a crosslinking and reinforcing agent. Attenuated total reflection–Fourier transform infrared spectroscopy and solid‐state13C‐NMR spectroscopy exposed the characteristics of the interfacial interaction in the hybrids and confirmed the existence of chemical bonds and hydrogen bonds between the epoxy group and SiOH. Scanning electron microscopy illustrated a good dispersion of silica in the ENR matrix. Meanwhile, the modulus at 100% elongation of the hybrid reached 9.64 MPa when 100‐phr silica was loaded; a similar trend was observed for the hardness. Finally, our findings might extend the concept of rubber curing and open a new space for making an environmentally friendly rubber composite. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2017,134, 44605.
A Redox‐anchoring Approach to Well‐dispersed MoCx/C Nanocomposite for Efficient Electrocatalytic Hydrogen Evolution
Authors: Zhou Yajun , Zhang Lingxia , Huang Weimin , Wang Min , Chen Lisong , Cui Xiangzhi , Zhang Xiaohua , Shi Jianlin 
Published: December 2016

AbstractHere we report a redox‐anchoring strategy for synthesizing a non‐noble metal carbide (MoCx) nanocomposite electrocatalyst for water electrolysis in acidic media, using glucose and ammonium heptamolybdate as carbon and Mo precursors, respectively, without the need of gaseous carbon sources such as CH4. Specifically, the aldehyde groups of glucose are capable of reducing Mo6+ to Mo4+ (MoO2), and thus molybdenum species can be well anchored by a redox reaction onto a carbon matrix to prevent the aggregation of MoCx nanoparticles during the following carbonization process. The morphology and chemical composition of the electrocatalysts were well characterized by BSE‐SEM, TEM, XRD and XPS. The obtained MoCx−2 sample showed a reasonably high hydrogen evolution reaction (HER) activity and excellent stability in an acidic electrolyte, and its overpotential required for a current density output of 20 mA cm−2 is as low as 193 mV. Such a prominent performance is ascribed to the excellent dispersity and nano‐size, and the large reactive surface area of MoCx particles. This work may open a new way to the design and fabrication of other non‐noble metal carbide nanocatalysts for various electrochemical applications.
CO Oxidation on Au Nanoparticles Supported on ZrO2: Role of Metal/Oxide Interface and Oxide Reducibility
Authors: Puigdollers Antonio Ruiz , Pacchioni Gianfranco 
Published: December 2016

AbstractIn this paper, we report the results of density functional theory calculations on CO oxidation on a model Au/ZrO2 catalyst, in which the support is a non‐reducible oxide (zirconia). Low‐temperature CO oxidation on supported gold nanoparticles occurs through direct interaction of an activated O2 molecule with adsorbed CO to form CO2. However, at room temperature or above the reaction follows another path as O2 desorbs from Au at 170 K. On a reducible oxide, such as TiO2, CO is directly oxidized by a lattice oxygen in a gold‐assisted Mars van Krevelen mechanism. The role of the oxide reducibility is thus essential, as the first step of the reaction is the formation of an oxygen vacancy. Contrary to what one would expect, the reaction can occur also on zirconia. We show that this is a result of the reduced oxygen vacancy formation energy at the gold/zirconia interface. The role of ambient oxygen is to reoxidize the support with a slightly activated process. The results point towards the importance of distinguishing between bulk reducibility and surface reducibility, as the latter can be strongly affected by phenomena such as deposition of metal nanoparticles or oxide nanostructuring.
Direct Electrophilic C−H Alkynylation of Unprotected 2‐Vinylanilines
Authors: Caspers Lucien D. , Finkbeiner Peter , Nachtsheim Boris J. 
Published: December 2016

AbstractUnprotected aromatic amines can be used as directing groups in metal‐catalyzed C−H alkynylations of alkenes. By using low amounts of an IrIII catalyst in combination with alkynylbenziodoxolones as electrophilic alkyne‐transfer reagents, highly desirable 1,3‐enynes were isolated in excellent yields of up to 98 % with Z stereoselectivity. A broad substrate scope as well as the high synthetic utility of the 1,3‐enynes render this new method an efficient approach for the synthesis of five‐ and six‐membered heterocycles. Further derivatizations of the 1,3‐enynes to highly substituted quinolines through AuI‐ and N‐bromosuccinimide‐mediated exo‐dig cyclizations were demonstrated.
Diversity of photoreceptor arrangements in nocturnal, cathemeral and diurnal Malagasy lemurs
Authors: Peichl Leo , Kaiser Alexander , Rakotondraparany Felix , Dubielzig Richard R. , Goodman Steven M. , Kappeler Peter M. 
Published: January 2017

AbstractThe lemurs of Madagascar (Primates: Lemuriformes) are a monophyletic group that has lived in isolation from other primates for about 50 million years. Lemurs have diversified into species with diverse daily activity patterns and correspondingly different visual adaptations. We assessed the arrangements of retinal cone and rod photoreceptors in six nocturnal, three cathemeral and two diurnal lemur species and quantified different parameters in six of the species. The analysis revealed lower cone densities and higher rod densities in the nocturnal than in the cathemeral and diurnal species. The photoreceptor densities in the diurnal Propithecus verreauxi indicate a less “diurnal” retina than found in other diurnal primates. Immunolabeling for cone opsins showed the presence of both middle‐to‐longwave sensitive (M/L) and shortwave sensitive (S) cones in most species, indicating at least dichromatic color vision. S cones were absent in Allocebus trichotis and Cheirogaleus medius, indicating cone monochromacy. In the Microcebus species, the S cones had an inverse topography with very low densities in the central retina and highest densities in the peripheral retina. The S cones in the other species and the M/L cones in all species had a conventional topography with peak densities in the central area. With the exception of the cathemeral Eulemur species, the eyes of all studied taxa, including the diurnal Propithecus, possessed a tapetum lucidum, a feature only found among nocturnal and crepuscular mammals.
High‐resolution data assimilation of cardiac mechanics applied to a dyssynchronous ventricle
Authors: Balaban Gabriel , Finsberg Henrik ,  Odland Hans Henrik , Rognes Marie E. , Ross Stian , Sundnes Joakim , Wall Samuel 
Published: December 2016

AbstractComputational models of cardiac mechanics, personalized to a patient, offer access to mechanical information above and beyond direct medical imaging. Additionally, such models can be used to optimize and plan therapies in‐silico, thereby reducing risks and improving patient outcome. Model personalization has traditionally been achieved by data assimilation, which is the tuning or optimization of model parameters to match patient observations. Current data assimilation procedures for cardiac mechanics are limited in their ability to efficiently handle high‐dimensional parameters. This restricts parameter spatial resolution, and thereby the ability of a personalized model to account for heterogeneities that are often present in a diseased or injured heart. In this paper, we address this limitation by proposing an adjoint gradient–based data assimilation method that can efficiently handle high‐dimensional parameters. We test this procedure on a synthetic data set and provide a clinical example with a dyssynchronous left ventricle with highly irregular motion. Our results show that the method efficiently handles a high‐dimensional optimization parameter and produces an excellent agreement for personalized models to both synthetic and clinical data.
Transition Metal Oxyfluorides for Next‐Generation Rechargeable Batteries
Authors: Deng Da 
Published: December 2016

AbstractTransition metal oxyfluorides are attracting much attention for next‐generation rechargeable batteries, including lithium‐ion batteries and those beyond lithium‐ion batteries. Mixed‐anion transition metal oxyfluorides offer the combined advantages of fluorides and the beneficial effects of oxides achieving improved capacity, high voltage, good conductivity and good cycling stability. Oxygen‐fluorine substitution can be employed to manipulate the physiochemical properties of those corresponding transition metal oxides and/or fluorides for rechargeable batteries, as cathode and/or anode materials, achieving improved electrochemical performances. However, it is still a challenging task to develop facile procedures to produce transition metal oxyfluorides, particularly difficult on a large scale and with high purity. Various methods and approaches have been developed over the years, typically based on solid state reactions. Recently, liquid‐based approaches under mild conditions for the preparation of transition metal oxyfluorides are attracting much attention. In this review, a number of transition metal oxyfluorides reported for rechargeable batteries, including VO2F, BiOF, FeOF, TiOF2, NbO2F, are discussed. Their synthetic approaches, limitations and electrochemical performances are reviewed. Transition metal oxyfluorides with the presence of strong electronegativity of fluorides are often suitable as positive electrode materials. For cathode applications, the author suggests that lithium‐free cathodes of transition metal oxyfluorides can be coupled with lithiated anodes to make as‐assembled charged‐state lithium‐ion batteries. The same concept can be employed to prepare charged state sodium‐ion batteries and other batteries using transition metal oxyfluorides as cathodes. The author suggests that as‐assembled batteries in charged state based on transition metal oxyfluorides (e.g., FeOF) as cathodes coupled with lithiated anodes will eventually be commercialized. The development of next‐generation lithium‐ion batteries and those so‐called beyond lithium‐ion batteries will depend on the capability to synthesize and produce high‐quality transition metal oxyfluorides on a large scale. Those transition metal oxyfluorides not only can find practical applications in batteries, but also can be employed as model electrode systems for fundamental mechanism studies.