bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intratest Variations in Trace Element Composition of Amphistegina lessonii Using Femtosecond‐Laser Ablation‐ICP‐Mass Spectrometry: A Field Study From Akajima, Okinawa Prefecture, Japan
Authors: Khanolkar Sonal , Schiebel Ralf , Singh Asmita , Saraswati Pratul Kumar , Jochum Klaus Peter , Weis Ulrike , Stoll Brigitte , Haug Gerald H. 
Published: January 2021

AbstractAmphistegina are common larger benthic foraminifer in coral reefs, with a nearly circumtropical distribution, and are major contributors to the CaCO3 budget of shallow marine environments. The family Amphisteginidae is dominant in Cenozoic carbonates. However, its potential as a proxy for paleoclimate reconstruction has not been completely explored. The intratest variability in trace elements of Amphistegina lessonii has been investigated using femtosecond‐laser ablation‐inductively coupled plasma‐mass spectrometry (fs‐LA‐ICP‐MS). We collected and analyzed adult specimens of A. lessonii in September 2003, November 2003, January 2004, and March 2004, from ∼2 m water depth in the coral reefs of Akajima, Okinawa, Japan. Tests of A. lessonii from these four collections were analyzed for Mg/Ca of the septa to observe Test Size‐Lifespan relationships. The lifespan of a specimen of A. lessonii of 1,200 µm in diameter is estimated at ∼3 and ∼2 months for specimens 900 µm in size. Over the estimated lifespans, Mg/Ca of individual specimens of A. lessonii is highly variable and displays co‐variation with temperature and tidal heights. Future projects may apply and further test this approach for the reconstruction of the tropical shallow marine paleoenvironments.
In Situ Mg/Ca Measurements on Foraminifera: Comparison Between Laser Ablation Inductively Coupled Plasma Mass Spectrometry and Wavelength‐Dispersive X‐Ray Spectroscopy by Electron Probe Microanalyzer
Authors: Balestra B. , Rose T. , Fehrenbacher J. , Knobelspiesse K. D. , Huber B. T. , Gooding T. , Paytan A. 
Published: January 2021

AbstractWe present a comparison of two different techniques: Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA‐ICP‐MS) and wavelength‐dispersive X‐Ray Spectroscopy by electron probe microanalyzer (EPMA) for obtaining Mg/Ca ratios in individual foraminifera shells. The goal is to assess the use of EPMA as an alternative technique for Mg/Ca analyses of single foraminiferal calcite shells. Foraminifera obtained from sediments (benthic, Uvigerina spp.) and from plankton tows (planktonic, Orbulina universa) were analyzed. All specimens were prepared in epoxy mounts and exposed in cross‐section such that multiple high‐resolution analyses could be completed on the shells using both techniques. We examined our data using statistical methods designed for the assessment and comparison of measurement techniques. In the case of Uvigerina, the mean difference for ratios obtained using EPMA and LA‐ICP‐MS is very small (−0.046 mmol mol−1) and scale independent. The Limits of Agreement (LoA, the standard deviation of the bias plus the mean bias) is [−0.315, 0.223] mmol mol−1. For samples with ratios lower than 13 mmol mol−1, we found a mean EPMA–LA‐ICP‐MS bias of −2.44 mmol mol−1 and a corresponding LoA of [−3.85, −1.04] mmol mol−1. For ratios higher than 13 mmol mol−1, there appears to be a scale dependent bias, meaning that the EPMA measured ratios become progressively larger than those of LA‐ICP‐MS as the Mg/Ca ratio increases, so the mean bias and LoA metrics are not meaningful. Results indicate that it is possible to use EPMA to collect Mg/Ca data, if the ratios are lower than ∼13 mmol mol−1.
Earth's Magnetotail as the Reservoir of Accelerated Single‐ and Multicharged Oxygen Ions Replenishing Radiation Belts
Authors: Panasyuk Mikhail I. , Zhukova Elena I. , Kalegaev Vladimir V. , Malova Helmi V. , Popov Victor Y. , Vlasova Natalia A. , Zelenyi Lev M. 
Published: January 2021

AbstractAcceleration of single‐ and multicharged oxygen ions in the perturbed Earth's magnetotail is investigated as the possible source of energetic heavy ions in the ring current. The numerical model is developed that allows evaluating the acceleration of oxygen ions O+‐O+8 in two possible scenarios of characteristic perturbations: (A) passage of multiple dipolarization fronts in the magnetotail; (B) passage of fronts followed by electromagnetic turbulence. It is shown that acceleration processes depend on particle charges as well as characteristic time scales of induced electric field variations. Maximum energies gained by oxygen ions correlate with values of their charges. Our simulations show that all kinds of single‐ and multiply charged heavy particles can be efficiently accelerated during multiple dipolarizations processes of the type (A) from initial energies 12 keV to maximum energies about several MeV. The gain of energies of heavy ions under the (B) scenario of magnetospheric perturbations is about 10% higher than in (A) scenario. The shapes of obtained in the model energy spectra were shown to be in agreement with experimental spectra in the range of L‐shells corresponding to ring/radiation belts. Therefore, we conclude that the Earth's magnetotail can play the role of the depot where oxygen ions of both ionospheric and solar wind origin can be effectively accelerated during magnetic substorms to energies about several MeV and then populate the ring current and radiation belts of the Earth.
A Geology and Geodesy Based Model of Dynamic Earthquake Rupture on the Rodgers Creek‐Hayward‐Calaveras Fault System, California
Authors: Harris R. A. , Barall M. , Lockner D. A. , Moore D. E. , Ponce D. A. , Graymer R. W. , Funning G. , Morrow C. A. , Kyriakopoulos C. , Eberhart‐Phillips D. 
Published: January 2021

AbstractThe Hayward fault in California's San Francisco Bay area produces large earthquakes, with the last occurring in 1868. We examine how physics‐based dynamic rupture modeling can be used to numerically simulate large earthquakes on not only the Hayward fault, but also its connected companions to the north and south, the Rodgers Creek and Calaveras faults. Equipped with a wealth of images of this fault system, including those of its 3D geology and 3D geometry, in addition to inferences about its interseismic creep‐rate pattern and rock‐friction behavior, we use a finite‐element computer code to perform 3D dynamic earthquake rupture simulations. We find that the rock properties affect the locations and amount of slip produced in our simulated large earthquakes. Crucial factors that control rupture behavior in our modeling are the earthquake nucleation locations, the fault geometry, and the data that reveal where the fault system is creeping or locked. Our findings suggest that large Rodgers Creek‐Hayward‐Calaveras‐Northern Calaveras (RC‐H‐C‐NC) fault‐system earthquakes may result from dynamic rupture that starts in a locked part of the fault system, but is then stopped by the creeping parts, leading to high‐magnitude‐6 earthquakes; or, from dynamic rupture that starts in a locked part of the fault system, then cascades through some of the creeping parts, leading to magnitude‐7 earthquakes.
Seasonal and Interannual Variability of the Subtropical Front in the New Zealand Region
Authors: Behrens Erik , Hogg Andrew McC. , England Matthew H. , Bostock Helen 
Published: January 2021

AbstractThe meridional variability of the Subtropical Front (STF) and the drivers of variability on interannual time scales in the New Zealand region are analyzed using a multi‐decadal eddy‐resolving ocean hindcast model, in comparison with Argo data. The STF marks the water mass boundary between subtropical waters and subantarctic waters, and is defined as the southern‐most location of the 11°C isotherm and 34.8 psu isohaline between 100 and 500 m. The STF shifts up to 650 km (6°) meridionally on seasonal timescales. In addition to seasonal variability, shifts of around 200 km (2°) occur on interannual time scales. These shifts are connected to regional wind stress curl anomalies in the eastern Tasman Sea and east of New Zealand, which trigger Ekman convergence/divergence and Rossby waves and result in meridional transport of heat and salt into/out of the Tasman Sea. The net transports across the northern boundary of the Tasman Sea show the largest sensitivity to these wind stress curl anomalies. During periods of positive wind stress curl anomalies and Ekman convergence, the heat and salt content increases shifting the position of the STF southward. The opposite tendency occurs during periods of negative wind stress curl anomalies. The migration of the STF does not appear to be directly linked to regional climate oscillations.
Continuous Multitrack Assimilation of Sentinel‐1 Precipitable Water Vapor Maps for Numerical Weather Prediction: How Far Can We Go With Current InSAR Data?
Authors: Mateus P. , Miranda P. M. A. , Nico G. , Catalao J. 
Published: January 2021

AbstractThe present study assesses the viability of including water vapor data from Interferometry Synthetic Aperture Radar (InSAR) in the initialization of numerical weather prediction (NWP) models, using already available Sentinel‐1 A and B products. Despite the limitations resulting from the 6‐day return period of images produced by the 2‐satellite system, it is found that for a sufficiently large domain designed to contain a set of images every 12 h (at varying locations), the impact on model performance is beneficial or at least neutral. The proposed methodology is tested in 24 consecutive 12 h forecasts, covering two cycles of the Sentinel‐1 system and 214 images, for a domain containing Iberia. A statistical analysis of the forecast precipitable water vapor (PWV) against independent GNSS observations concluded for relevant improvements in the different scores, especially during a consecutive 3‐day period where the standard initial data were less accurate. An analysis of the rain forecasts against gridded remote sensing observations further indicates an overall improvement in the grid‐point distribution of different precipitation classes throughout the simulation, even when the mean impact of PWV assimilation was not significant. It is suggested that current InSAR data are already a useful source of NWP data and will only become more relevant as new systems are put into operation.
Obliquity, Precession, and Fracture Mechanics: Implications of Europa's Global Cycloid Population
Authors: Rhoden Alyssa Rose , Mohr Kyle J. , Hurford Terry A. , Henning Wade , Sajous Stan , Patthoff D. Alex , Dubois David 
Published: January 2021

AbstractWe catalog the global inventory of Europa's cycloids, arcuate fractures whose paths have been linked to diurnal tidal stress, and use the locations and orientations of their cusps to further test the formation mechanism of cycloids and constrain Europa's rotation state. We find that the global distribution of cycloids is better explained by a precessing spin pole than longitude translation due to nonsynchronous rotation, which is consistent with studies of Europa's strike‐slip faults and linear fractures. We also find that a small obliquity can reproduce the orientations of most cycloid cusps at their current locations, outperforming a model using stress from eccentricity alone. Matching cycloid locations and cusp orientations under these conditions implies a variable failure threshold and that most cusps form at stresses that are 50%–90% of the local peak tidal stress, suggesting that periodic deformation is causing failure through fatigue. The fact that cycloids are not observed in some regions, despite the low failure stresses implied by some cusp orientations, suggests an additional control on cusp formation that was not included in our simplified model. We hypothesize that the larger amplitude of tidal stress in some regions leads to fatigue‐induced failure after fewer tidal cycles, leading to a build‐up of cycloids in those regions. Why more linear fractures do not seem limited in location or density is still unknown. More physically informed constraints on how ice fails under low, periodic deformation and across generations of fractures would be helpful in interpreting Europa's cycloids.
Transparent Exopolymer Particles in a Coastal Frontal Zone of the Northern South China Sea and the Associated Biogeochemical Implications
Authors: Li Qian P. , Ge Zaiming , Liu Zijia , Zhou Weiwen , Shuai Yiping , Wu Zhengchao 
Published: January 2021

AbstractTransparent exopolymer particles (TEP) are essential for the ocean carbon cycle. However, their relationships with physical and biogeochemical processes remain inadequately understood in the coastal ocean. Here, we focus on TEP dynamics across a temperature front in the coastal waters of the Northern South China Sea (NSCS). Our results suggested that TEP concentration was relatively high across the frontal system with 35.0–160.5 μg Xeq L−1 (μg Gum Xanthan equivalent per liter) in the surface waters, 70.0–197.2 μg Xeq L−1 in the bottom waters, and 12.1–16.3 mg Xeq g−1 in the surficial sediment. In the surface layer of the front, TEP distributions appeared to be driven by cross‐front physical and biogeochemical variations, as it showed significant correlations with both temperature and nutrients, as well as chlorophyll‐a along with its size‐fractionated components. TEP dominated on the shore side of the front with high phytoplankton biomass and intense TEP production in the surface layer. In contrast, there were much lower TEP concentrations and higher TEP production efficiencies on the seaside driven by nutrient limitation. In the bottom layer of the frontal zone, sediment resuspension associated with the front's secondary circulation was found to play a crucial role in enhancing the levels of TEP‐rich aggregates with prominent distribution patterns characterized by the localized accumulation in the bottom waters at the frontal zone. Our results provide valuable insights about the controlling factors that modulate TEP dynamics in a coastal frontal system and highlighted their potential role in the carbon cycling of the NSCS shelf‐sea.
A Comprehensive Review of Specific Yield in Land Surface and Groundwater Studies
Authors: Lv Meizhao , Xu Zhongfeng , Yang Zong‐Liang , Lu Hui , Lv Meixia 
Published: January 2021

AbstractSpecific yield is a key parameter for estimating water table depth in land surface models, which can strongly modulate the interaction between soil moisture and groundwater and further affect the water budget between the land surface and the atmosphere. The error in water table simulation comes mainly from the uncertainty in determining the specific yield. The determination of specific yield in land surface models is simplified, and a uniform empirical constant value of specific yield is generally used in global simulations, especially for deep aquifers, for its convenience. However, a uniform fixed value is insufficient for worldwide aquifers with diverse environments. Before estimating specific yields for global aquifers in Earth system simulations, a comprehensive understanding of the specific yield and comparison of current determination methods are required. This study provides a comprehensive review of the literature focusing on different concepts of the specific yield, complex variabilities, and various determination methods. Specifically, we detail the distinction and interconversion of different subconcepts that are used to reflect the influence of different factors on the specific yield and are likely to confuse scholars; present the representative comparisons of previous estimated specific yields using different methods, and summarize the applicabilities and limitations of these methods, indicating directions for their future improvement.
Satellite Observations of Strong Plasma Wave Emissions With Frequency Shifts Induced by an Engine Burn From the Cygnus Spacecraft
Authors: Bernhardt Paul A. , Griffin Michael K. , Bougas William C. , Howarth Andrew D. , James H. Gordon , Siefring Carl L. , Briczinski Stanley J. 
Published: January 2021

AbstractA new discovery was made using the radio receiver instrument on the Canadian enhanced polar outflow probe (e‐POP) showing that strong plasma wave emissions (SPWE) are seen near 17 kHz and 300 Hz. The frequency of these emissions are affected by small injections of neutral gas from the Cygnus spacecraft. The technique of using a 150 g/s thruster to change frequencies and intensities of plasma waves has provided evidence that a finite kz lower hybrid mode may the source of the SPWE waves. SPWE observations in space are a sensitive diagnostic tool to measure both natural and manmade changes in the earth's ion composition.
Seismic Imaging of an Intracrustal Deformation in the Northwestern Margin of the South China Sea: The Role of a Ductile Layer in the Crust
Authors: Huang Haibo , Klingelhoefer Frauke , Qiu Xuelin , Li Yuhan , Wang Ping 
Published: January 2021

AbstractThe continental margins of the South China Sea (SCS) have undergone episodic rifting since the Cenozoic, and there are ongoing debates surrounding the processes of crustal deformation and seafloor opening. In this work, we present a P‐wave velocity model extending from the north of Xisha Trough to the Zhongshanan Basin in the northwestern SCS margin, using ocean bottom seismometer data of the wide‐angle seismic profile OBS2013‐1. The results show that the crust thins symmetrically across the western Xisha Trough, from more than ∼20 km at the flanks to ∼10 km in the central valley where the sedimentary layers thicken to over 6 km. In the Zhongsha Trough, closer to the deep basin, the upper crust is detached in a ∼20 km wide region and the lower crust has seismic velocities increased by more than ∼0.3 km/s. The top boundary of the lower crust is located at a depth of ∼13 km across the Zhongsha Trough, and a ∼5 km thick midcrustal ductile layer is imaged. A ∼50 km wide ocean‐continent transition region beneath the Zhongshanan Basin characterizes a ∼6 km thick continental crust underlain by serpentinized and magnetized upper mantle. These observations, together with plate reconstructions based on gravity and magnetic analysis, suggest that deformation of the continental margin was controlled by a ductile crustal layer. Magmatism, associated with the early stage oceanic accretion, has mixed with the highly extended continental crust. Developments of the failed rifted basins were controlled by the westward propagation of the continental breakup.
Public Water Waste Reporting: Contextual Correlates and Conservation Outcomes
Authors: Zhang Y. , Teodoro M. P. , Switzer D. 
Published: January 2021

AbstractThe success of water conservation restrictions depends in part on governments' capacity to monitor water use. Inviting the general public to report instances of water waste is one means of expanding government capacity to monitor and enforce water use. Why are people in some communities more frequently engaged in such “participatory surveillance” than in other communities? Does participatory surveillance help achieve conservation goals? We explore the social correlates and conservation outcomes of participatory surveillance regimes with an analysis of water conservation in the U.S. state of California. During California's historic 2014–2017 drought, the state established hotlines and websites for the public to report water waste anonymously. Californians responded by reporting more than 485,000 water waste complaints over the course of the emergency. Analysis shows that besides the water supply characteristics and drought severity, several social and institutional factors correlate strongly with complaint volume. Specifically, we find that municipal and special district utilities received more complaints than investor‐owned utilities, and that complaints correlated positively with communities' level of education and partisan competition. We do not find strong evidence that communities' income, income distributions, and racial/ethnic compositions correlate with overall reporting. We further find that complaints are positively associated with conservation outcomes. Taken together, results indicate that social contexts can influence participation in participatory surveillance, and that participatory surveillance can be a potent means of enhancing water restrictions during a drought emergency.
Employing a systematic approach to biobanking and analyzing clinical and genetic data for advancing COVID-19 research
Authors:   GEN-COVID Multicenter Study, Daga Sergio , Fallerini Chiara , Baldassarri Margherita , Fava Francesca , Valentino Floriana , Doddato Gabriella , Benetti Elisa , Furini Simone , Giliberti Annarita , Tita Rossella , Amitrano Sara , Bruttini Mirella , Meloni Ilaria , Pinto Anna Maria , Raimondi Francesco , Stella Alessandra , Biscarini Filippo , Picchiotti Nicola , Gori Marco , Pinoli Pietro , Ceri Stefano , Sanarico Maurizio , Crawley Francis P. , Birolo Giovanni , Renieri Alessandra , Mari Francesca , Frullanti Elisa 
Published: January 2021

AbstractWithin the GEN-COVID Multicenter Study, biospecimens from more than 1000 SARS-CoV-2 positive individuals have thus far been collected in the GEN-COVID Biobank (GCB). Sample types include whole blood, plasma, serum, leukocytes, and DNA. The GCB links samples to detailed clinical data available in the GEN-COVID Patient Registry (GCPR). It includes hospitalized patients (74.25%), broken down into intubated, treated by CPAP-biPAP, treated with O2supplementation, and without respiratory support (9.5%, 18.4%, 31.55% and 14.8, respectively); and non-hospitalized subjects (25.75%), either pauci- or asymptomatic. More than 150 clinical patient-level data fields have been collected and binarized for further statistics according to the organs/systems primarily affected by COVID-19: heart, liver, pancreas, kidney, chemosensors, innate or adaptive immunity, and clotting system. Hierarchical clustering analysis identified five main clinical categories: (1) severe multisystemic failure with either thromboembolic or pancreatic variant; (2) cytokine storm type, either severe with liver involvement or moderate; (3) moderate heart type, either with or without liver damage; (4) moderate multisystemic involvement, either with or without liver damage; (5) mild, either with or without hyposmia. GCB and GCPR are further linked to the GCGDR, which includes data from whole-exome sequencing and high-density SNP genotyping. The data are available for sharing through the Network for Italian Genomes, found within the COVID-19 dedicated section. The study objective is to systematize this comprehensive data collection and begin identifying multi-organ involvement in COVID-19, defining genetic parameters for infection susceptibility within the population, and mapping genetically COVID-19 severity and clinical complexity among patients.