bluuebunny/crossref_metadata_2025_split huggingface dataset:
Conducting Event-Related Potential (ERP) Research With Young Children
Authors: Brooker Rebecca J. , Bates John E. , Buss Kristin A. , Canen Mara J. , Dennis-Tiwary Tracy A. , Gatzke-Kopp Lisa M. , Hoyniak Caroline , Klein Daniel N. , Kujawa Autumn , Lahat Ayelet , Lamm Connie , Moser Jason S. , Petersen Isaac T. , Tang Alva , Woltering Steven , Schmidt Louis A. 
Published: July 2019

Abstract. There has been an unprecedented increase in the number of research studies employing event-related potential (ERP) techniques to examine dynamic and rapidly occurring neural processes with children during the preschool and early childhood years. Despite this, there has been relatively little discussion of the methodological and procedural differences that exist for studies of young children versus older children and adults. That is, reviewers, editors, and consumers of this work often expect developmental studies to simply apply adult techniques and procedures to younger samples. Procedurally, this creates unrealistic expectations for research paradigms, data collection, and data reduction and analyses. Scientifically, this leads to inappropriate measures and methods that hinder drawing conclusions and advancing theory. Based on ERP work with preschoolers and young children from 10 laboratories across North America, we present a summary of the most common ERP components under study in the area of emotion and cognition in young children along with 13 realistic expectations for data collection and loss, laboratory procedures and paradigms, data processing, ERP averaging, and typical challenges for conducting this type of work. This work is intended to supplement previous guidelines for work with adults and offer insights to aid researchers, reviewers, and editors in the design and evaluation of developmental research using ERPs. Here we make recommendations for researchers who plan to conduct or who are conducting ERP studies in children between ages 2 and 12 years, focusing on studies of toddlers and preschoolers. Recommendations are based on both data and our cumulative experience and include guidelines for laboratory setup, equipment and recording settings, task design, and data processing.
Evaluating the Association of High Trait Anxiety With a Bias in Familiarity-Based Recognition of Emotional Stimuli
Authors: Barg Gabriel , Carboni Alejandra , Roche Thomas , Nin Verónica , Carretié Luis 
Published: July 2019

Abstract. In the past decades the role of cognitive biases as maintaining factors of anxiety has been widely researched. This theoretical framework assumes that vulnerability self-referential thoughts promote a hyper-vigilant mode of processing environmental stimuli. In this mode, threatening information increases attentional capture and therefore encoding and retrieval of such stimuli is enhanced. Although this attentional bias has been confirmed, the evidence concerning the memory bias is contradictory. Our hypothesis is that the bias in memory is expressed through the pattern of recognition. Particularly, the aim of this study was to evaluate the association of anxiety with familiarity, a deficient form of recognition which consists only in the identification of the item without retrieval of contextual information. Two groups of 17 participants with low and high anxiety levels performed an experimental task of visual recognition memory, using neutral, positive, and negative pictures. The experiment had two test phases, with a 24-hour interval, to evaluate possible effects of consolidation. The pattern of recognition was measured, behaviorally (through an independent Remember/Know paradigm) and through event-related potentials (ERP). Participants with higher levels of anxiety developed a bias in recognition of arousing stimuli (positive and negative) compared with the control group. This bias was observed behaviorally through an increase of familiarity-based recognition, and was associated with a positive modulation of a right parietal late positive component (LPC) at approximately 600 ms of latency. Participants with higher levels of anxiety are capable of recognizing arousing stimuli but lack efficiency in retrieving past contextual information compared to lower level anxiety participants. A recognition bias can be the first step in cognitive distortions that generate anxiety. This is, to our knowledge, the first study to explore the association of anxiety with familiarity-based recognition, using an independent Remember/Know paradigm combined with electrophysiological data. Further studies with bigger samples and more recording channels are needed to confirm the electrophysiological findings.
Long‐Term Evolution of The Surface Refractivity for Arctic Regions
Authors: Bettouche Y. , Obeidat H. , Agba B. , Kouki A. , Alhassan H. , Rodriguez Jonathan , Abd‐Alhameed R. , Jones S. 
Published: July 2019

AbstractIn this paper, local meteorological data for a period of 35 years (from 1979 to 2013) from Kuujuaq station have been used to calculate the surface refractivity, N (a link for the data is available in the acknowledgements), and to estimate the vertical refractivity gradient, dN1, in the lowest atmospheric layer above the ground. Monthly and yearly variations of the mean of N and dN1 are provided. The values obtained are compared with the corresponding values from the ITU maps. The long‐term trend of the surface refractivity is also investigated. The data demonstrate that the indices N and dN1 are subject to an evolution that may have significance in the context of climate change. Monthly means of N show an increasing departure from ITU‐R values since 1990. Yearly mean values of the dN1 show a progressive decrease over the period of study. Seasonal means of dN1 show a decrease over time, especially for summer. Such a trend may increase the occurrence of superrefraction. However, currently available ITU‐R recommendations for microwave link design assume a stationary climate, so there is a need for a new modeling approach.
Coherent South American Monsoon Variability During the Last Millennium Revealed Through High‐Resolution Proxy Records
Authors: Campos J. L. P. S. , Cruz F. W. , Ambrizzi T. , Deininger M. , Vuille M. , Novello V. F. , Strikis N. M. 
Published: July 2019

AbstractThe number of paleoprecipitation records from the South American Monsoon domain that cover the last millennium has increased substantially in past years. However, hitherto most studies focused only on regional aspects, thereby neglecting the role of large‐scale monsoon variability and the mechanisms that link proxy locations in space and time. Here we decompose the South American Monsoon into its main modes of variability by applying a Monte Carlo principal component analysis to a compilation of 11 well‐dated summer paleoprecipitation records from tropical South America. The first mode represents changes in precipitation over the core monsoon domain, while the second mode is characterized by high loadings along the fringes of the South American Monsoon over Southeastern South America and the northern monsoon limit. Composite analysis reveals an enhanced monsoon with a wider, rather than a southward displaced, South Atlantic Convergence Zone during the early Little Ice Age, in contrast to previous interpretations.
Impact of Confining Stress on Capillary Pressure Behavior During Drainage Through Rough Fractures
Authors: da Silva Josimar A. , Kang Peter K. , Yang Zhibing , Cueto‐Felgueroso Luis , Juanes Ruben 
Published: July 2019

AbstractWe study, numerically, the behavior of capillary pressure (Pc) during slow immiscible displacement in a rough fracture as a function of the degree of fracture aperture heterogeneity that results from two distinct mechanisms: normal confining stress and fracture surface correlation. We generate synthetic self‐affine rough fractures at different correlation scales, solve the elastic contact problem to model the effect of confining stress, and simulate slow immiscible displacement of a wetting fluid by a nonwetting one using a modified invasion percolation model that accounts for in‐plane curvature of the fluid‐fluid interface. Our modeling results indicate that the power spectral density, S(f), of Pc, can be used to qualitatively characterize fracture aperture heterogeneity. We show that the distribution of forward avalanche sizes follows a power law
, with exponent α=2, in agreement with previously reported values for porous media and equal to the expected theoretical exponent for a self‐organized criticality process.
Using Satellite‐Based Vegetation Cover as Indicator of Groundwater Storage in Natural Vegetation Areas
Authors: Bhanja Soumendra N. , Malakar Pragnaditya , Mukherjee Abhijit , Rodell Matthew , Mitra Pabitra , Sarkar Sudeshna 
Published: July 2019

AbstractNormalized Difference Vegetation Index (NDVI) is widely used as an efficient indicator of vegetation cover. Here we assess the possibility of using NDVI as an indicator of groundwater storage. We used groundwater level (GWL) obtained from in situ groundwater observation wells (n > 15,000) in India in 2005–2013. Good correlation (r > 0.6) is observed between NDVI and GWL in natural vegetation‐covered areas, that is, forest lands, shrubs, and grasslands. We apply artificial neural network and support vector machine approaches to investigate the relationship between GWL and NDVI using both of the parameters as input. Artificial neural network‐ and support vector machine‐simulated GWL matches very well with observed GWL, particularly in naturally vegetated areas. Thus, we interpret that NDVI may be used as a suitable indicator of groundwater storage conditions in certain areas where the water table is shallow and the vegetation is natural and where in situ groundwater observations are not available.
Retracted: Organic Carbon Pools in the Subsea Permafrost Domain Since the Last Glacial Maximum
Authors: Mu Cuicui , Zhang Tingjun , Abbott Benjamin W. , Wang Kang , Ge Shemin , Sayedi Sayedeh Sara , Fan Chengyan , Peng Xiaoqing 
Published: July 2019

AbstractSea level rise after the Last Glacial Maximum inundated several million square kilometers of Arctic permafrost, while estimates of organic carbon (OC) quantity and vulnerability to mineralization are exceedingly uncertain. We compiled geophysical measurements from Arctic continental shelves to estimate current subsea permafrost OC stocks. We found that marine transgression since the Last Glacial Maximum inundated approximately 3.92×106 km2 of permafrost, which contained 1,460±1,010 Pg OC in the top 25 m of sediment. We estimated that current subsea permafrost underlies an area of 2.30×106 km2 and contains 860±590 Pg OC, not including methane hydrates. Most of the ~600 Pg of OC that thawed after the marine transgression is still present on the continental shelves. Although our estimates of subsea OC storage remain highly uncertain due to the sparse and uneven distribution of data, they suggest that current estimates of subsea OC substantially underestimate a major component of the global carbon cycle.
Tropical Atlantic Cooling and Freshening in the Middle of the Last Interglacial From Coral Proxy Records
Authors: Brocas William M. , Felis Thomas , Mudelsee Manfred 
Published: July 2019

AbstractThe last interglacial (LIG; Marine Isotope Substage 5e, ~127–117 ka) experienced globally warmer than modern temperatures; however, profound differences in regional climate occurred that are relevant to the assessment of future climate change scenarios. Tropical Atlantic sea surface temperature (SST) and hydrology are intrinsic to the spatiotemporal evolution of past and future climate. We present eight monthly resolved coral Sr/Ca and δ18O records (130–118 ka) to reconstruct mean western tropical Atlantic SST and seawater δ18O changes during the LIG. Cooler and fresher than modern surface waters are indicated for the middle of the LIG at ~126 ka. This was followed by a rapid transition to modern‐like SSTs and salinities that characterized the remaining part of the LIG. Our results, which account for differences found among corals, proxies, and SST calibration uncertainties, agree with western tropical Atlantic sediment records. Together, they suggest that an oceanic regime existed that differed from today.
Saturation Characteristics of Parallel EMIC Waves in the Inner Magnetosphere
Authors: Yu Xiongdong , Yuan Zhigang 
Published: July 2019

AbstractIn this letter, detailed evolution process of parallel electromagnetic ion cyclotron waves in the inner magnetosphere has been investigated through quasilinear theory. A new saturation has been found to occur after the usual first saturation. During the interval between these two saturations, the energy transfers from H+ band to He+ band electromagnetic ion cyclotron waves. Moreover, through a best fitting, we obtain new model parameters for the anisotropy‐beta inverse relation of hot H+, which identifies the threshold of ion cyclotron instabilities in the inner magnetosphere. In situ observations of the Van Allen Probe mission also verify these new model parameters. Therefore, our results reveal the evolution process and saturation characteristics of parallel electromagnetic ion cyclotron waves in the inner magnetosphere.
An Observation‐Based Correction for Aerosol Effects on Nitrogen Dioxide Column Retrievals Using the Absorbing Aerosol Index
Authors: Cooper Matthew J. , Martin Randall V. , Hammer Melanie S. , McLinden Chris A. 
Published: July 2019

AbstractRetrievals of nitrogen dioxide (NO2) and other trace gases from satellite measurements rely on accurate calculation of an air mass factor (AMF) to account for the atmospheric light path. Scattering and absorption of sunlight by aerosols affects AMFs by impacting the sensitivity of satellite‐observed radiances to NO2 at different altitudes. Current NO2 retrievals either do not explicitly account for these effects or rely on aerosol information from an external source. Here we investigate a method for quantifying the impact of aerosols on NO2 AMFs using the Absorbing Aerosol Index, a satellite‐based measure of light absorption and scattering by aerosols. We find a robust relationship between the Absorbing Aerosol Index and the aerosol correction to NO2 AMFs using the GEOS‐Chem chemical transport model and the LIDORT radiative transfer model. This relationship enables estimating the impact of aerosols on AMFs using observed Absorbing Aerosol Index values, thus yielding an observation‐based aerosol correction for NO2 retrievals.
Whistler Instability Driven by Electron Thermal Ring Distribution With Magnetospheric Application
Authors: Yoon P. H. , Lee Junggi , Hwang Junga , Seough J. , Choe G. S. 
Published: July 2019

AbstractThe loss cone electron distribution function can be unstable to the excitation of whistler instability, which can be effective in pitch angle diffusion, thus rapidly filling up the loss cone and removing the free energy source. The present paper carries out a combined quasi‐linear analysis and one‐dimensional particle‐in‐cell simulation in order to investigate the dynamical consequences of the excitation of whistler instability. Thermal ring distribution can be considered as a simple substitution for the actual loss cone distribution. It is found according to both the reduced quasi‐linear theory and the particle‐in‐cell simulation that while the whistler instability is effective in pitch angle diffusion of the initial loss cone distribution, the complete isotropization is not achieved such that substantial loss cone persists in the saturation stage. This finding may explain the fundamental question of why weak loss cone feature persists in the magnetosphere and, more importantly, why charged particles trapped in dipole field do not steadily undergo pitch angle scattering and be lost eventually.
Bayesian Dynamic Finite‐Fault Inversion: 2. Application to the 2016 Mw 6.2 Amatrice, Italy, Earthquake
Authors: Gallovič F. , Valentová Ľ. , Ampuero J.‐P. , Gabriel A.‐A. 
Published: July 2019

AbstractIn 2016 Central Italy was struck by a sequence of three normal‐faulting earthquakes with moment magnitude (Mw) larger than 6. The Mw 6.2 Amatrice event (24 August) was the first one, causing building collapse and about 300 casualties. The event was recorded by a uniquely dense network of seismic stations. Here we perform its dynamic source inversion to infer the fault friction parameters and stress conditions that controlled the earthquake rupture. We consider a linear slip‐weakening friction law with spatially variable parameters along the fault. The inversion uses a novel Bayesian framework developed in our companion paper, which combines efficient finite‐difference dynamic rupture simulations and the Parallel Tempering Monte Carlo algorithm to sample the posterior probability density function. The main advantage of such formulation is that by subsequent analysis of the posterior samples we can infer stable features of the result and their uncertainty. The inversion results in a million of visited models. The preferred model ensemble reveals intriguing dynamic features. The rupture exhibits a slow and irregular nucleation followed by bilateral rupture propagation through two asperities, accelerating toward the heavily damaged city of Amatrice. The stress drop reaches locally 10–15 MPa, with slip‐weighted mean of 4–4.5 MPa. The friction drop ranges from 0.1 to 0.4. The characteristic slip‐weakening distance is the most heterogeneously distributed dynamic parameter, with values of 0.2–0.8 m. The radiation efficiency was rather low, 0.2, suggesting that approximately 80% of the total available energy was spent in the fracture process, while just 20% was radiated by seismic waves.
High‐Angular Resolution Electron Backscatter Diffraction as a New Tool for Mapping Lattice Distortion in Geological Minerals
Authors: Wallis D. , Hansen L. N. , Britton T. B. , Wilkinson A. J. 
Published: July 2019

AbstractAnalysis of distortions of the crystal lattice within individual mineral grains is central to the investigation of microscale processes that control and record tectonic events. These distortions are generally combinations of lattice rotations and elastic strains, but a lack of suitable observational techniques has prevented these components being mapped simultaneously and routinely in earth science laboratories. However, the technique of high‐angular resolution electron backscatter diffraction (HR‐EBSD) provides the opportunity to simultaneously map lattice rotation and elastic strain gradients with exceptional precision, on the order of 0.01° for rotations and 10−4 in strain, using a scanning electron microscope. Importantly, these rotations and lattice strains relate to densities of geometrically necessary dislocations and residual stresses. Recent works have begun to apply and adapt HR‐EBSD to geological minerals, highlighting the potential of the technique to provide new insights into the microphysics of rock deformation. Therefore, the purpose of this review is to provide a summary of the technique, to identify caveats and targets for further development, and to suggest areas where it offers potential for major advances. In particular, HR‐EBSD is well suited to characterizing the roles of different dislocation types during crystal plastic deformation and to mapping heterogeneous internal stress fields associated with specific deformation mechanisms/microstructures or changes in temperature, confining pressure, or macroscopic deviatoric stress. These capabilities make HR‐EBSD a particularly powerful new technique for analyzing the microstructures of deformed geological materials.
Insights From Closed‐Form Expressions for Injection‐ and Production‐Induced Stresses in Displaced Faults
Authors: Jansen J. D. , Singhal P. , Vossepoel F. C. 
Published: July 2019

AbstractWe consider fluid‐induced seismicity and present closed‐form expressions for the elastic displacements, strains, and stresses resulting from injection into or production from a reservoir with displaced faults. We apply classic inclusion theory to two‐dimensional finite‐width and infinite‐width reservoir models. First, we simplify the fault model to the bare minimum while still maintaining its essential features: a vertical fault in a homogeneous reservoir of infinite width in an infinite domain. We confirm and sharpen findings from earlier numerical studies and furthermore conclude that the development of infinitely large elastic shear stresses in a displaced fault, at the internal and external reservoir/fault corners, implies that even small amounts of injection or production will result in some amount of slip or other nonelastic deformation. Another finding is that there is a marked difference between the shear stress patterns resulting from injection and production in a reservoir with a displaced fault. In both situations two slip patches emerge but at the start of injection some amount of slip occurs immediately in the overburden and underburden, whereas during production the slip may remain inside the reservoir region. Next we derive similar but more complicated expressions for displaced inclined (normal or reverse) faults and conclude that our findings for vertical faults also apply to inclined faults.
Decoupling of timescales reveals sparse convergent CPG network in the adult spinal cord
Authors: Radosevic Marija , Willumsen Alex , Petersen Peter C. , Lindén Henrik , Vestergaard Mikkel , Berg Rune W. 
Published: July 2019

AbstractDuring the generation of rhythmic movements, most spinal neurons receive an oscillatory synaptic drive. The neuronal architecture underlying this drive is unknown, and the corresponding network size and sparseness have not yet been addressed. If the input originates from a small central pattern generator (CPG) with dense divergent connectivity, it will induce correlated input to all receiving neurons, while sparse convergent wiring will induce a weak correlation, if any. Here, we use pairwise recordings of spinal neurons to measure synaptic correlations and thus infer the wiring architecture qualitatively. A strong correlation on a slow timescale implies functional relatedness and a common source, which will also cause correlation on fast timescale due to shared synaptic connections. However, we consistently find marginal coupling between slow and fast correlations regardless of neuronal identity. This suggests either sparse convergent connectivity or a CPG network with recurrent inhibition that actively decorrelates common input.
Fully phase-stabilized quantum cascade laser frequency comb
Authors: Consolino Luigi , Nafa Malik , Cappelli Francesco , Garrasi Katia , Mezzapesa Francesco P. , Li Lianhe , Davies A. Giles , Linfield Edmund H. , Vitiello Miriam S. , De Natale Paolo , Bartalini Saverio 
Published: July 2019

AbstractMiniaturized frequency comb sources across hard-to-access spectral regions, i.e. mid- and far-infrared, have long been sought. Four-wave-mixing based Quantum Cascade Laser combs (QCL-combs) are ideal candidates, in this respect, due to the unique possibility to tailor their spectral emission by proper nanoscale design of the quantum wells. We demonstrate full-phase-stabilization of a QCL-comb against the primary frequency standard, proving independent and simultaneous control of the two comb degrees of freedom (modes spacing and frequency offset) at a metrological level. Each emitted mode exhibits a sub-Hz relative frequency stability, while a correlation analysis on the modal phases confirms the high degree of coherence in the device emission, over different power-cycles and over different days. The achievement of fully controlled, phase-stabilized QCL-comb emitters proves that this technology is mature for metrological-grade uses, as well as for an increasing number of scientific and technological applications.