bluuebunny/crossref_metadata_2025_split huggingface dataset:
Atrazine residues in flooded and nonflooded soil and effects on soybean
Authors: Mueller Thomas C. , Kincer David R. , Steckel Lawrence E. 
Published: September 2020

AbstractAtrazine applied at planting is commonly used for weed control in corn. With global climate change causing an increase in river flooding in the United States over the past decade, producers need information to determine the best course of action in flooded fields treated with atrazine into which they wish to immediately plant soybean. Studies were designed to understand the effect of flooding on atrazine residual activity including atrazine concentration, soybean injury, and soybean yield. In 2012, soybean yield in flooded treatments was reduced by prior atrazine application. In 2014, soybean injury was <10% in all plots, and nonflooded, atrazine-treated soils had yields equal to the nontreated. Findings from this research indicated that it is possible for producers to consider replanting soybean after atrazine application, with appropriate changes to product labeling.
Apatite Fission Track Signatures of the Ross Sea Ice Flows During the Last Glacial Maximum
Authors: Li X. , Zattin M. , Olivetti V. 
Published: September 2020

AbstractThe catchment for the Ross Sea ice includes both the East and the West Antarctic ice sheets, but the mass balance is a direct response to climate change. Our work is aimed to reconstruct the ice flows after the Last Glacial Maximum and is based on apatite fission track data from samples collected from 18 piston cores across the Ross Sea embayment. Fission track ages have been divided into meaningful populations and then compared with bedrock ages from West and East Antarctica. Furthermore, fission track lengths have been measured on each population and then compared through forward modeling with thermal histories derived from literature. The widespread presence of apatites with cooling ages of about 30–40 Ma reveals a main exhumation phase of the Transantarctic Mountains during the Oligocene associated to the last phases of the West Antarctic Rift System. Furthermore, the presence of key marker apatites (e.g., younger than 21 Ma or older than 230 Ma) allows to identify the Central High as a major ice flow divide.
The Complexity of the 2018 Kaktovik Earthquake Sequence in the Northeast of the Brooks Range, Alaska
Authors: Xu Guangyu , Xu Caijun , Wen Yangmao , Xiong Wei , Valkaniotis Sotiris 
Published: September 2020

AbstractWe use mainly geodetic observations to constrain the fault geometry and coseismic distribution of the 2018 Kaktovik earthquake sequence, Alaska. We find that at least three faults were activated. The earthquake sequence ruptured mainly an ESE‐striking, SSW‐dipping strike‐slip fault and a secondary rupture on an SE‐striking, SW‐dipping normal fault. Slip also occurred on a small SSW‐striking fault plane, which is found first in geodetic data and further verified with geological data and focal mechanism solutions. We also map 6 months of postseismic deformation and find obvious displacements in the center of the Sadlerochit Mountains. A geological model is proposed to interpret the relationship between this earthquake sequence and the regional structure. We suggest that the 2018 Kaktovik earthquake sequence may first have occurred on a fault unknown prior to the mainshock and triggered slip on both the pre‐existing ramp structure below the Sadlerochit Mountains and a secondary structure.
Abyssal Pathways and the Double Silica Maximum in the Northeast Pacific Basin
Authors: Hautala Susan L. , Hammond Douglas E. 
Published: September 2020

AbstractThis study examines causes of the double silica maximum in the deep interior Northeast Pacific Basin using a stochastic Lagrangian tracer model based on steady‐state advective fields and diapycnal diffusion established by a hydrographic inverse method that conserves potential vorticity and salinity. Lateral diffusion, unresolved by the inverse model, is adjusted for overall agreement with radiocarbon distribution. The double silica maximum in vertical profiles arises from an eastern‐intensified single maximum in the North Pacific Deep Water along the northern domain boundary (originating in the western Pacific), and a strong subarctic bottom source supplying silica to Upper Circumpolar Deep Water density surfaces that successively intersect the seafloor over a broad area east of 150°W, associated geostrophically with southward flow. The existence of the double silica maximum requires weak diapycnal transport in the deep interior, with broader implications for the conceptual picture of meridional overturning circulation in the North Pacific.
Cross‐Over Infrared Spectroscopy: A New Tool for the Remote Determination of Olivine Composition
Authors: Kremer C. H. , Mustard J. F. , Pieters C. M. 
Published: September 2020

AbstractOlivine ([Mg,Fe]2SiO4) has been remotely detected on numerous solar system bodies, but its composition has been only partially constrained using visible‐near infrared (VNIR, 0.5–3 μm) and midinfrared (MIR, 8–15 μm) spectra. Meanwhile, the spectral character of olivine in the “cross‐over” region of the infrared (4–8 μm) remains generally unexplored. We examine the relationship between olivine Mg# (molar Mg/[Mg + Fe] × 100) and the wavelength positions of two strong, discrete overtone‐combination bands at ~5.6 and ~6.0 μm. In reflectance and thermal emission spectra measured for 47 synthetic and natural olivine samples that span the Mg‐Fe solid solution, we find that the 5.6 and 6.0 μm bands shift systematically to longer wavelengths by 0.11 and 0.10 μm, respectively, with increasing Fe content. Our results indicate that olivine Mg# may be determined within ±10 mol% forsterite using the positions of these two bands, making “cross‐over” region spectroscopy a potentially powerful remote sensing tool.
Unusual Changes in the Antarctic Middle Atmosphere During the 2019 Warming in the Southern Hemisphere
Authors: Eswaraiah S. , Kim Jeong‐Han , Lee Wonseok , Hwang Junyoung , Kumar Kondapalli Niranjan , Kim Yong Ha 
Published: September 2020

AbstractA rare sudden stratosphere warming (SSW) occurred in the Southern Hemisphere polar region in 2019. The polar stratosphere temperature and planetary wave (PW) enhancements are found to be unusual from the history for 40 years; hence, it is an “Extremely‐Rare” SSW. The distinct features of the mesosphere winds were observed during the SSW, in association with the traveling PWs in the stratosphere. The mesosphere zonal winds reversed for about 20 days before the peak SSW. Meteor radar (MR) and Modern‐Era Retrospective Analysis for Research and Applications (MERRA)‐2 observations indicate that the zonal wind reversal was descended with time, and the reversal was larger over ~72°S than the MR site (62°S). The MR detected the PWs of 14–22 days before and 8–12 days following the SSW in the mesosphere. We further noticed the enhancement of wavenumber 1 signature in the mesosphere during the peak SSW over the polar region. Thus, the polar middle‐atmosphere is greatly affected by the SSW.
A New Technique for Investigating Dust Charging in the PMSE Source Region
Authors: Mahmoudian Alireza , Kosch Mike J. , Vierinen Juha , Rietveld Michael T. 
Published: September 2020

AbstractA new technique for investigating dust charging in the PMSE (polar mesospheric summer echoes) source region is proposed and discussed in this paper. The first high‐frequency (HF) modulation of the PMSE with varying pump power was employed during a recent experimental campaign at EISCAT (European Incoherent Scatter Scientific Association). Two experiment setups including HF pump power stepping as well as quasi‐continuous power sweeping were used. The experiment was designed based on a computational model capable of simulation of PMSE evolution during HF pump modulation in order to develop a new approach for studying the dust charging process in the PMSE source region. The charge state of dust particles along with background dusty plasma parameters is estimated using the experimental and computational results. A detailed future experimental design based on background dusty‐plasma parameters is proposed.
Latitudinal Response of Storm Activity to Abrupt Climate Change During the Last 6,500 Years
Authors: Yang Yang , Maselli Vittorio , Normandeau Alexandre , Piper David J. W. , Li Michael Z. , Campbell D. Calvin , Gregory Taylor , Gao Shu 
Published: September 2020

AbstractThis study examines the influence of the strength of Atlantic Meridional Overturning Circulation (AMOC) on storminess at different latitudes in the North Atlantic, based on a new 6.5‐Kyr record of large storms from the Scotian Shelf (Eastern Canada) that provides the first >3.5‐ka record from middle latitudes. Comparison with a compilation of other paleostorm records shows that peaks in storminess are at times synchronous (4.5–2.5 and since 0.5 ka) between low and middle latitudes but in the intervening period (2.5–0.5 ka) were latitudinally asynchronous. Synchronous (asynchronous) behavior correlates with sustained increase (decrease) of AMOC. Regime shifts in storm activity between low and middle latitudes were more frequent since 2.5 ka, related to increased frequency of abrupt climate changes. These findings indicate a latitudinal response of storm activity due to abrupt climate change, which is critical to correctly assess future storm risks along the North Atlantic coastline.
The Global Distribution of Ultralow‐Frequency Waves in Jupiter's Magnetosphere
Authors: Manners H. , Masters A. 
Published: September 2020

AbstractJupiter's giant magnetosphere is a complex system seldom in a configuration approximating steady state, and a clear picture of its governing dynamics remains elusive. Crucial to understanding how the magnetosphere behaves on a large scale are disturbances to the system on length‐scales comparable to the cavity, which are communicated by magnetohydrodynamic waves in the ultralow‐frequency band (<1 mHz). In this study we used magnetometer data from multiple spacecraft to perform the first global heritage survey of these waves in the magnetosphere. To map the equatorial region, we relied on the large local‐time coverage provided by the Galileo spacecraft. Flyby encounters performed by Voyager 1 and 2, Pioneer 10 and 11, and Ulysses provided local‐time coverage of the dawn sector. We found several hundred events where significant wave power was present, with periods spanning ∼5–60 min. The majority of events consisted of multiple superposed discrete periods. Periods at ∼15, ∼30, and ∼40 min dominated the event‐averaged spectrum, consistent with the spectra of quasi‐periodic pulsations often reported in the literature. Most events were clustered in the outer magnetosphere close to the magnetopause at noon and dusk, suggesting that an external driving mechanism may dominate. The most energetic events occurred close to the planet, though more sporadically, indicating an accumulation of wave energy in the inner magnetosphere or infrequent impulsive drivers in the region. Our findings suggest that dynamics of the system at large scales is modulated by this diverse population of waves, which permeate the magnetosphere through several cavities and wave guides.
Benthic Respiration in Hypoxic Waters Enhances Bottom Water Acidification in the Northern Gulf of Mexico
Authors: Wang Hongjie , Lehrter John , Maiti Kanchan , Fennel Katja , Laurent Arnaud , Rabalais Nancy , Hussain Najid , Li Qian , Chen Baoshan , Scaboo K. Michael , Cai Wei‐Jun 
Published: September 2020

AbstractIt is known that surface water eutrophication enhances bottom water ocean acidification via respiration in coastal oceans. However, the role of benthic processes in influencing bottom water acidification has not been sufficiently explored. We examined this issue by analyzing a 10‐year summer carbonate chemistry dataset in bottom water together with recent benthic flux measurements and literature benthic flux data in the northern Gulf of Mexico. The difference between the observed and estimated pH (Ω) values calculated from anthropogenic CO2 increase and water column aerobic respiration were defined as ΔpH (ΔΩ). We found that ΔpH and ΔΩ values in hypoxic condition were −0.03 ± 0.04 (mean ± standard deviation) and −0.15 ± 0.39, respectively. Both ΔpH and ΔΩ values in hypoxic conditions were significantly lower than zero (p < 0.05). The net results of anaerobic respiration, oxidation of reduced chemcials, burial of iron sulfide minerals, and possible CaCO3 dissolution may have led to an alkalinity to DIC production ratio of less than 1 in porewater. This caused the ratio of alkalinity to dissolved inorganic carbon fluxes from sediment to bottom water to be less than 1, which led to additional bottom water acidification. Our analysis and model simulations demonstrate that severe hypoxic and anoxic conditions, which correspond to less water movement, favor the accumulation of benthic respiration products, leading to additional pH and Ω reductions. The findings on sediment processes contributing to acidification in bottom waters provide new insights into the sensitivity of coastal ocean acidification to low‐oxygen conditions under current and future climates and anthropogenic nutrient loading scenarios.
A Continental Shelf Pump for CO2 on the Adélie Land Coast, East Antarctica
Authors: Arroyo Mar C. , Shadwick Elizabeth H. , Tilbrook Bronte , Rintoul Stephen R. , Kusahara Kazuya 
Published: September 2020

AbstractWe quantify the transport of inorganic carbon from the continental shelf to the deep ocean in Dense Shelf Water (DSW) from the Mertz and Ninnis Polynyas along the Adélie Land coast in East Antarctica. For this purpose, observations of total dissolved inorganic carbon (TCO2) from two summer hydrographic surveys in 2015 and 2017 were paired with DSW volume transport estimates derived from a coupled ocean‐sea ice‐ice shelf model to examine the fate of inorganic carbon in DSW from Adélie Land. Transports indicate a net outflow of 227 ± 115 Tg C yr−1 with DSW in the postglacial calving configuration of the Mertz Polynya. The greatest outflow of inorganic carbon from the shelf region was delivered through the northern boundary across the Adélie and Mertz Sills, with an additional transport westward from the Mertz Polynya. Inorganic carbon in DSW is derived primarily from inflowing TCO2‐rich modified Circumpolar Deep Water; local processes (biological productivity, air‐sea exchange of CO2, and the addition of brine during sea ice formation) make much smaller contributions. This study proposes that DSW export serves as a continental shelf pump for CO2 and is a pathway to sequester inorganic carbon from the shallow Antarctic continental shelf to the abyssal ocean, removing CO2 from atmospheric exchange on the time scale of centuries.
Radio Interferometer Observations of an Energetic in‐Cloud Pulse Reveal Large Currents Generated by Relativistic Discharges
Authors: Tilles Julia N. , Krehbiel Paul R. , Stanley Mark A. , Rison William , Liu Ningyu , Lyu Fanchao , Cummer Steven A. , Dwyer Joseph R. , Senay Seda , Edens Harald , Fan Xiangpeng , Brown Robert G. , Wilson Jennifer 
Published: September 2020

AbstractThe production mechanism for terrestrial gamma ray flashes (TGFs) is not entirely understood, and details of the corresponding lightning activity and thunderstorm charge structure have yet to be fully characterized. Here we examine sub‐microsecond VHF (14–88 MHz) radio interferometer observations of a 247‐kA peak‐current EIP, or energetic in‐cloud pulse, a reliable radio signature of a subset of TGFs. The EIP consisted of three high‐amplitude sferic pulses lasting ≃60 μs in total, which peaked during the second (main) pulse. The EIP occurred during a normal‐polarity intracloud lightning flash that was highly unusual, in that the initial upward negative leader was particularly fast propagating and discharged a highly concentrated region of upper‐positive storm charge. The flash was initiated by a high‐power (46 kW) narrow bipolar event (NBE), and the EIP occurred about 3 ms later after ≃3 km upward flash development. The EIP was preceded ≃200 μs by a fast 6 × 106 m/s upward negative breakdown and immediately preceded and accompanied by repeated sequences of fast (107–108 m/s) downward then upward streamer events each lasting 10 to 20 μs, which repeatedly discharged a large volume of positive charge. Although the repeated streamer sequences appeared to be a characteristic feature of the EIP and were presumably involved in initiating it, the EIP sferic evolved independently of VHF‐producing activity, supporting the idea that the sferic was produced by relativistic discharge currents. Moreover, the relativistic currents during the main sferic pulse initiated a strong NBE‐like event comparable in VHF power (115 kW) to the highest‐power NBEs.
Ionospheric Irregularities Observed During the GLEAM Survey
Authors: Helmboldt J. F. , Hurley‐Walker N. 
Published: September 2020

AbstractNearly 200 hr of observing with the Murchison Widefield Array (MWA) radio telescope during the Galactic and Extragalactic All‐sky MWA (GLEAM) survey was used to assemble images of ionospheric structure. These images cover a nearly 50° wide area on the sky at a cadence of 10 min over many 5–7 hr long observing runs. They are generated by tracking the apparent motions of ∼200–800 cosmic radio sources caused by changes in the transverse gradient of the ionospheric total electron content. Spectral analysis of these images revealed that the data set was dominated by three distinct signatures. The first is consistent with field‐aligned structures within the topside ionosphere/lower plasmasphere previously imaged with the MWA. The second are structures that are relatively large and aligned nearly east/west. Regional weather data imply that these are preferentially detected when there is a noticeable shear within the subtropical jet stream, which passes near the MWA. This suggests that this signature may be related to gravity waves launched by jet stream shear. The final signature is consistent with the properties of so‐called electrobuoyancy waves that are known to occur at midlatitudes at night. Detections of these were more common when regional sporadic E (ES) was present, supporting a proposed connection between these waves and polarization electric fields that may arise within ES. We discuss the implications for future observations with the Square Kilometer Array.
Prediction of independence in bowel function after spinal cord injury: validation of a logistic regression model
Authors: Khan Omar , Badhiwala Jetan H. , Fehlings Michael G. 
Published: September 2020

Abstract
Study design
Retrospective analysis of prospectively collected data.

Objectives
Recently, logistic regression models were developed to predict independence in bowel function 1 year after spinal cord injury (SCI) on a multicenter European SCI (EMSCI) dataset. Here, we evaluated the external validity of these models against a prospectively accrued North American SCI dataset.

Setting
Twenty-five SCI centers in the United States and Canada.

Methods
Two logistic regression models developed by the EMSCI group were applied to data for 277 patients derived from three prospective multicenter SCI studies based in North America. External validation was evaluated for both models by assessing their discrimination, calibration, and clinical utility. Discrimination and calibration were assessed using ROC curves and calibration curves, respectively, while clinical utility was assessed using decision curve analysis.

Results
The simplified logistic regression model, which used baseline total motor score as the predictor, demonstrated the best performance, with an area under the ROC curve of 0.869 (95% confidence interval: 0.826–0.911), a sensitivity of 75.5%, and a specificity of 88.5%. Moreover, the model was well calibrated across the full range of observed probabilities and displayed superior clinical benefit on the decision curve.

Conclusions
A logistic regression model using baseline total motor score as a predictor of independent bowel function 1 year after SCI was successfully validated against an external dataset. These findings provide evidence supporting the use of this model to enhance the care for individuals with SCI.
Interaction between adverse childhood experiences and polygenic risk in patients with bipolar disorder
Authors: Park Young-Min , Shekhtman Tatyana , Kelsoe John R. 
Published: September 2020

AbstractThe interaction between genes and environment often occurs when they depend on one another. We hypothesized that adverse childhood experiences (ACEs) would interact with genetic predispositions to bipolar disorder (BD), demonstrating earlier age at onset (AAO) and worse clinical outcomes. We aimed to clarify the effects of the interaction between ACEs and genetic susceptibility using polygenic risk score (PRS) on AAO and clinical outcomes. Single nucleotide polymorphisms and clinical data, including ACEs, were obtained from the Bipolar Genomic Study, which contains a large sample of BD participants. A total of 1615 subjects with BD I were obtained and divided into two groups according to the presence or absence of ACEs and an additional four groups based on the number of ACEs (none versus one versus two versus ≥ three types). ACEs was evaluated using the childhood life events scale (CLES). BD–PRS was obtained from the Psychiatric Genomics Consortium, which compared BD patients and healthy controls. The BD–PRS was higher in the group with ACEs than without ACEs at most p-value thresholds. In multivariate linear regression analyses, both groups with more ACEs and higher BD–PRS were independently and interactively associated with an earlier AAO of BD; however, only greater ACEs were associated with worsened clinical outcome. These findings highlight the clinical importance of evaluating ACEs and polygenic risk in research of the etiology of BD.
miR-196b-5p-mediated downregulation of FAS promotes NSCLC progression by activating IL6-STAT3 signaling
Authors: Huang Xiangjie , Xiao Sisi , Zhu Xinping , Yu Yun , Cao Meng , Zhang Xiaodong , Li Shaotang , Zhu Wangyu , Wu Fengjiao , Zheng Xiaohui , Jin Libo , Xie Congying , Huang Xiaoying , Zou Peng , Li Xiaokun , Cui Ri 
Published: September 2020

AbstractOur recent study demonstrated that the QKI-5 regulated miRNA, miR-196b-5p, and it functions as an onco-microRNA in non-small cell lung cancer (NSCLC) by directly targeting GATA6 and TSPAN12. However, the role of miR-196b-5p in NSCLC progression and metastasis still remains unclear. We found that miR-196b-5p promotes lung cancer cell proliferation and colony formation by directly targeting tumor suppressor, FAS. The expression of FAS was significantly downregulated in NSCLC tissue samples and was negatively correlated with the miR-196b-5p expression. Knocking down FAS activates NFkB signaling and subsequent IL6 secretion, resulting in phosphorylation of signal transducer and activator of transcription 3 (STAT3) to promote lung cancer cell growth. Our findings indicated that miR-196b-5p might exhibit novel oncogenic function by FAS-mediated STAT3 activation in NSCLC, and suggested that targeting the miR-196b-5p/FAS/NFkB/IL6/STAT3 pathway might be a promising therapeutic strategy in treating NSCLC.