bluuebunny/crossref_metadata_2025_split huggingface dataset:
Weedy rice update in Arkansas, USA, and adjacent locales
Authors: Roma-Burgos Nilda , Butts Thomas R. , Werle Isabel S. , Bottoms Sunny , Mauromoustakos Andy 
Published: July 2021

AbstractWeedy rice (Oryza sativaL.) is among the most problematic weeds in rice (Oryza sativaL.) production. The commercialization of herbicide-resistant (HR) rice nearly two decades ago provided an effective tool to manage weedy rice; however, resistance evolution and volunteer HR hybrid rice kept weedy rice at the forefront of rice weed control needs. This research aimed to assess the prevalence and severity of weedy rice infestations, identify production practices that may have contributed to an increase in weedy rice, and determine control strategies that may still be effective on weedy rice across Arkansas and adjacent U.S. Midsouth locales. Two questionnaires, one for rice growers and consultants and one for County Extension agents (CEAs), were distributed through email and physical copies in 2020. Thirty-three respondents returned the rice grower (25) and consultant (8) survey, representing 26 and 7 counties in Arkansas and the Missouri Bootheel area, respectively, as well as four parishes in northeast Louisiana. Eighteen respondents returned the CEA survey. Respondents ranked weedy rice the third most problematic weed in rice, behindEchinochloaspp. andCyperusspp. The most common infestation levels reported in 78% of fields was less than 12 m−2. Crop rotation (64% growers/consultants, 50% CEAs) and HR rice technology (27% growers/consultants, 50% CEAs) were the top two most-effective methods for weedy rice management, respectively. Tillage and crop rotation practices significantly influenced weedy rice infestation. Rice–soybean [Glycine max(L.) Merr.] rotation had the lowest weedy rice infestation compared with rice monoculture and other crop rotation practices. Crop rotation was not practiced on 26% of reported fields, primarily due to poor drainage. The imidazolinone (IMI)-resistant rice technology was still effective (>70% control) in 60% of fields, but quizalofop-resistant rice is needed to control IMI-resistant weedy rice. Overall, weedy rice remains a challenging weed in rice production.
Hydraulics and Turbidity Generation in the Milandre Cave (Switzerland)
Authors: Vuilleumier Cécile , Jeannin Pierre‐Yves , Hessenauer Marc , Perrochet Pierre 
Published: July 2021

AbstractKarst aquifers may convey significant sediment fluxes, as displayed by the intense turbidity peaks commonly observed at karst springs. The understanding of the origin of the suspended solids discharged at springs is key in assessing spring vulnerability and securing drinking water quality. The mechanisms for turbidity generation and sediment transport in karst are however difficult to investigate because of the general lack of access to the karst conduits. These processes have been examined in the Milandre Cave, which hosts a karst drain of regional importance, for more than 10 years by means of turbidity monitoring both inside and at the outlets of this karst system. Additionally, the composition of the suspended load (particle‐size distribution andEscherichia colicontent) has been monitored over the course of a flood event. These data are compared against a numerical simulation of the mean boundary shear stress inside the conduit network. The following conceptual model for sediment transport through the system is derived: during minor flood events, most of the turbidity comes from underground sediment remobilization, while during medium to intense flood events, soil‐derived turbidity also reaches the spring. Hydraulics in the epiphreatic zone is tightly linked with autochthonous turbidity generation (mostly during the flooding and the flushing of conduits). In comparison, allochthonous turbidity is associated with finer particles, higherE. coli, and higher UV fluorescence. This improves the overall understanding of turbidity generation and could help the monitoring and forecast of pollution events at drinking water supplies.
Urbanization Impacts on Evapotranspiration Across Various Spatio‐Temporal Scales
Authors: Mazrooei Amir , Reitz Meredith , Wang Dingbao , Sankarasubramanian A. 
Published: July 2021

AbstractUrbanization has been shown to locally increase the nighttime temperatures creating urban heat islands, which partly arise due to evapotranspiration (ET) reduction. It is unclear how the direction and magnitude of the change in local ET due to urbanization varies globally across different climatic regimes. This knowledge gap is critical, both for the key role of ET in the energy and water balance accounting for the majority of local precipitation, and for reducing the urban heat island effect. We explore and assess the impacts of urbanization on monthly and mean annual ET across a range of landscapes from local to global spatial scales. Remotely sensed land cover and ET available at 1 km resolution are used to quantify the differences in ET between urban and surrounding non‐urban areas across the globe. The observed patterns show that the statistically significant difference between urban and non‐urban ET can be estimated to first order as a function of local hydroclimate, with arid regions seeing increased ET, and humid regions showing decreased ET. Cities under cold climates also evaporate more than their non‐urban surroundings during the winter, as the urban micro‐climate has increased energy availability resulting from human activities. Increased ET in arid cities arises from municipal water withdrawals and increased irrigation during drought conditions. These results can help inform planners to improve the integration of environmental conditions into the design and management of urban landscapes.
Internal and External Modulation of Folding Rates With 104to 105 Year Time Resolutions From Growth Strata, Pico del Aguila, Spain
Authors: Anastasio David J. , Kodama Kenneth P. , Parés Josep M. , Hinnov Linda A. , Idleman Bruce D. 
Published: July 2021

AbstractHigh‐resolution cyclostratigraphy in growth strata are used to reconstruct unsteady folding rates at the regional‐scale Pico del Aguila anticline, southern Pyrenees, to evaluate deformation modulation. Magnetic polarity stratigraphy was used to calibrate cyclostratigraphy‐based anhysteretic remanent magnetization intensity variations to establish precessional frequencies in the growth strata record. The astronomically tuning was used to determine sedimentation rates and absolute time. Incremental tilting rates were calculated between selected horizons over ∼6 myr of fold growth. Careful treatment of uncertainties enhances confidence that the results are meaningful and results show significant variability in folding rates over time. The acceleration phase of fold growth was variable, punctuated by a prolonged period of tectonic quiescence, and correlated to sedimentation changes in the wedge‐top basin. Low dipping bedding intrinsically modulated the initial rates of folding for the first 25° of limb tilt, until ∼38.86 Ma. Then, halotectonics in the Paleogene Jaca Basin extrinsically modulated accelerating folding rates for the next 45° of limb tilting, until ∼37.42 Ma. Finally, forelimb‐steepening leading to geometric strain hardening and blunted folding rates for the last 17° of fold tightening and causing a thrust fault to cut the anticline's core. Folding ended at Pico del Aguila ∼35.10 Ma. Calculated folding rates varied between 0° ± 5.5°and 90° ± 19°/myr over 100s kyr time increments. Variations in the folding rate of the Pico del Aguila décollement anticline are attributed to both intrinsic modulation as a result of progressive bedding steepening during folding and extrinsic modulation as a result of variable deltaic sedimentation rates in the wedge‐top basin.
Magnetic Reconnection Near the Planet as a Possible Driver of Jupiter’s Mysterious Polar Auroras
Authors: Masters A. , Dunn W. R. , Stallard T. S. , Manners H. , Stawarz J. 
Published: July 2021

AbstractAuroral emissions have been extensively observed at the Earth, Jupiter, and Saturn. These planets all have appreciable atmospheres and strong magnetic fields, and their auroras predominantly originate from a region encircling each magnetic pole. However, Jupiter’s auroras poleward of these “main” emissions are brighter and more dynamic, and the drivers responsible for much of these mysterious polar auroras have eluded identification to date. We propose that part of the solution may stem from Jupiter’s stronger magnetic field. We model large‐scale Alfvénic perturbations propagating through the polar magnetosphere toward Jupiter, showing that the resulting <0.1° deflections of the magnetic field closest to the planet could trigger magnetic reconnection as near as ∼0.2 Jupiter radii above the cloud tops. At Earth and Saturn this physics should be negligible, but reconnection electric field strengths above Jupiter’s poles can approach ∼1 V m−1, typical of the solar corona. We suggest this near‐planet reconnection could generate beams of high‐energy electrons capable of explaining some of Jupiter’s polar auroras.
The Trends of Warm‐Season Thunderstorm and Lightning Days in China and the Influence of Environmental Factors
Authors: Xue Xiaoying , Ren Guoyu , Xu Xiangde , Sun Xiubao , Yang Guowei , Zhang Panfeng , Zhang Siqi 
Published: July 2021

AbstractPrevious studies indicated that numbers of meso‐micro scale severe convective weather exhibited a significant decrease over China's mainland in the past decades. However, the possible mechanism of the decrease has not been well understood. This paper analyzes the changes in frequency of thunderstorm and lightning days using an updated data set of denser national observational stations and theirs links to the atmospheric circulation and regional environmental factors. The results confirm the highly significant decreasing trend of frequency of thunderstorm and lightning days during 1961–2013, with the decreasing rates of −2.6 days/10 years and −6.5 days/10 years in the warm season, respectively. The decrease of geopotential height difference between south and north, the weakening of westerly jet strength at 200 hPa and the decline of zonal wind speed of high level are found to be the direct reasons for the wide‐spread decrease of thunderstorm and lightning days across the country. Meanwhile, there is a significant positive correlation between thunderstorm days and convective available potential energy (CAPE), indicating a reduction of potential atmospheric instability accompanying the decline of thunderstorm days especially in the south of China. The decrease in the relative humidity at the lower troposphere, the weakening of 0–6 km vertical wind shear and the accompanying slackening of actual convective activity, may have also contributed to the downward trends of the severe convective weather. Our analysis shows a strong link of the decreasing thunderstorm and lightning days to the long‐term changes of the atmospheric circulation and environmental factors. Further investigation is needed to examine what have driven the changes of the environmental factors over the time period.
Using Passive Air Samplers to Quantify Vertical Gaseous Elemental Mercury Concentration Gradients Within a Forest and Above Soil
Authors: Quant M. Isabel , Feigis Michelle , Mistry Shreya , Lei Ying Duan , Mitchell Carl P. J. , Staebler Ralf , Di Guardo Antonio , Terzaghi Elisa , Wania Frank 
Published: July 2021

AbstractGaseous elemental mercury (GEM), the primary form of mercury (Hg) in the atmosphere, can undergo bidirectional exchange with the Earth's surface, with uptake in growing vegetation constituting the dominant atmospheric deposition process. Whereas direction and magnitude of this exchange can be determined using micrometeorological and chamber techniques, these approaches are complex, costly and labor‐intensive, and often only yield fluxes over relatively short time‐scales at few sites. We demonstrate that an inexpensive and easy‐to‐use passive air sampler can identify and quantify vertical GEM concentration gradients on scales ranging from centimeters to tens of meters over long time periods (up to 1.5 years) and with coarse temporal resolution (monthly to seasonally). Samplers were deployed above clean and contaminated soil and through a deciduous forest canopy at two sites in Southern Ontario. Significant and seasonally variable gradients of GEM concentrations, both increasing and decreasing with height above ground, were observed and can be explained through the influence of factors such as soil contamination, canopy growth, temperature, solar irradiance, and snow cover. At a minimum, the sampler can identify the GEM flux direction, but, when combined with the Modified Bowen Ratio method, can also be used to estimate the evaporative GEM flux from mercury‐contaminated soil. We further demonstrate the application of the approach to contaminated site assessment, using a field in Brescia, Italy, known to contain elevated levels of Hg in soil. By allowing for cost‐effective measurements at multiple sites and over extended time periods, passive sampling complements existing techniques for studying atmosphere‐surface exchange of GEM.
Detecting Ground Level Enhancements Using Soil Moisture Sensor Networks
Authors: Hands A. D. P. , Baird F. , Ryden K. A. , Dyer C. S. , Lei F. , Evans J. G. , Wallbank J. R. , Szczykulska M. , Rylett D. , Rosolem R. , Fowler S. , Power D. , Henley E. M. 
Published: July 2021

AbstractGround level enhancements (GLEs) are space weather events that pose a potential hazard to the aviation environment through single event effects in avionics and increased dose to passengers and crew. The existing ground level neutron monitoring network provides continuous and well‐characterized measurements of the radiation environment. However, there are only a few dozen active stations worldwide, and there has not been a UK‐based station for several decades. Much smaller neutron detectors are increasingly deployed throughout the world with the purpose of using secondary neutrons from cosmic rays to monitor local soil moisture conditions (COSMOS). Space weather signals from GLEs and Forbush decreases have been identified in COSMOS data. Monte Carlo simulations of atmospheric radiation propagation show that a single COSMOS detector is sufficient to detect the signal of a medium‐strength (10%–100% increase above background) GLE at high statistical significance, including at fine temporal resolution. Use of fine temporal resolution would also provide a capability to detect Terrestrial Gamma Ray Flashes (via secondary neutrons) which are produced by certain lightning discharges and which can provide a hazard to aircraft, particularly in tropical regions. We also show how the COsmic‐ray Soil Moisture Observing System‐UK detector network could be used to provide warnings at the International Civil Aviation Organization “Moderate” and “Severe” dose rate thresholds at aviation altitudes, and how multiple‐detector hubs situated at strategic UK locations could detect a small GLE at high statistical significance and infer crucial information on the nature of the primary spectrum.
Spontaneous apoptosis of cells in therapeutic stem cell preparation exert immunomodulatory effects through release of phosphatidylserine
Authors: He Xuemei , Hong Weiqi , Yang Jingyun , Lei Hong , Lu Tianqi , He Cai , Bi Zhenfei , Pan Xiangyu , Liu Yu , Dai Lunzhi , Wang Wei , Huang Canhua , Deng Hongxin , Wei Xiawei 
Published: July 2021

AbstractMesenchymal stem cell (MSC)-mediated immunomodulation has been harnessed for the treatment of human diseases, but its underlying mechanism has not been fully understood. Dead cells, including apoptotic cells have immunomodulatory properties. It has been repeatedly reported that the proportion of nonviable MSCs in a MSC therapeutic preparation varied from 5~50% in the ongoing clinical trials. It is conceivable that the nonviable cells in a MSC therapeutic preparation may play a role in the therapeutic effects of MSCs. We found that the MSC therapeutic preparation in the present study had about 5% dead MSCs (DMSCs), characterized by apoptotic cells. Namely, 1 × 106 MSCs in the preparation contained about 5 × 104 DMSCs. We found that the treatment with even 5 × 104 DMSCs alone had the equal therapeutic effects as with 1 × 106 MSCs. This protective effect of the dead MSCs alone was confirmed in four mouse models, including concanavalin A (ConA)- and carbon tetrachloride (CCl4)-induced acute liver injury, LPS-induced lung injury and spinal cord injury. We also found that the infused MSCs died by apoptosis in vivo. Furthermore, the therapeutic effect was attributed to the elevated level of phosphatidylserine (PS) upon the injection of MSCs or DMSCs. The direct administration of PS liposomes (PSLs) mimic apoptotic cell fragments also exerted the protective effects as MSCs and DMSCs. The Mer tyrosine kinase (MerTK) deficiency or the knockout of chemokine receptor C–C motif chemokine receptor 2 (CCR2) reversed these protective effects of MSCs or DMSCs. These results revealed that DMSCs alone in the therapeutic stem cell preparation or the apoptotic cells induced in vivo may exert the same immunomodulatory property as the “living MSCs preparation” through releasing PS, which was further recognized by MerTK and participated in modulating immune cells.
Local bi-fidelity field approximation with Knowledge Based Neural Networks for Computational Fluid Dynamics
Authors: Pepper Nick , Gaymann Audrey , Sharma Sanjiv , Montomoli Francesco 
Published: July 2021

AbstractThis work presents a machine learning based method for bi-fidelity modelling. The method, a Knowledge Based Neural Network (KBaNN), performs a local, additive correction to the outputs of a coarse computational model and can be used to emulate either experimental data or the output of a more accurate, but expensive, computational model. An advantage of the method is that it can scale easily with the number of input and output features. This allows bi-fidelity modelling approaches to be applied to a wide variety of problems, for instance in the bi-fidelity modelling of fields. We demonstrate this aspect in this work through an application to Computational Fluid Dynamics, in which local corrections to a velocity field are performed by the KBaNN to account for mesh effects. KBaNNs were trained to make corrections to the free-stream velocity field and the boundary layer. They were trained on a limited data-set consisting of simple two-dimensional flows. The KBaNNs were then tested on a flow over a more complex geometry, a NACA 2412 airfoil. It was demonstrated that the KBaNNs were still able to provide a local correction to the velocity field which improved its accuracy. The ability of the KBaNNs to generalise to flows around new geometries that share similar physics is encouraging. Through knowledge based neural networks it may be possible to develop a system for bi-fidelity, computer based design which uses data from past simulations to inform its predictions.
Influence of nano-VC on the structural and magnetic properties of MnAlC-alloy
Authors: Shtender Vitalii , Stopfel Henry , Hedlund Daniel , Karlsson Dennis , Pothala Rajasekhar , Skårman Björn , Olsson Fredrik , Vidarsson Hilmar , Andersson Gabriella , Svedlindh Peter , Sahlberg Martin 
Published: July 2021

AbstractAlloys of Mn55Al45C2 with additions of VC nano-particles have been synthesized and their properties evaluated. The Mn55Al45C2(VC)x (x = 0.25, 0.5 and 1) alloys have been prepared by induction melting resulting in a high content of the ferromagnetic τ-phase (> 94 wt.%). Powder X-ray diffraction indicates that nano-VC can be dissolved in the alloy matrix up to 1 at.%. On the other side, metallography investigations by scanning electron microscopy and scanning transmission electron microscope show inclusions of the nanosized additives in the microstructure. The effect of nano-VC on the grain and twin boundaries has been studied by electron backscattering diffraction. The magnetization has been measured by magnetometry up to 9 T while the domain structure has been studied using both magnetic force microscopy as well as Kerr-microscopy. For nano-VC contents above 0.25 at.%, a clear increase of the coercive force is observed, from 57 to 71 kA/m. The optimum appears to be for 0.5 at.% nano-VC which shows a 25% increase in coercive force without losing any saturation magnetization. This independent increase in coercivity is believed to originate from the nano-VC reducing the overall magnetic domain size. Overall, we observe that addition of nano-VC could be an interesting route to increase the coercive force of MnAl, without sacrificing saturation magnetization.
Theoretical investigation of pre-symptomatic SARS-CoV-2 person-to-person transmission in households
Authors: Arav Yehuda , Klausner Ziv , Fattal Eyal 
Published: July 2021

AbstractSince its emergence, the phenomenon of SARS-CoV-2 transmission by seemingly healthy individuals has become a major challenge in the effort to achieve control of the pandemic. Identifying the modes of transmission that drive this phenomenon is a perquisite in devising effective control measures, but to date it is still under debate. To address this problem, we have formulated a detailed mathematical model of discrete human actions (such as coughs, sneezes, and touching) and the continuous decay of the virus in the environment. To take into account those discrete and continuous events we have extended the common modelling approach and employed a hybrid stochastic mathematical framework. This allowed us to calculate higher order statistics which are crucial for the reconstruction of the observed distributions. We focused on transmission within a household, the venue with the highest risk of infection and validated the model results against the observed secondary attack rate and the serial interval distribution. Detailed analysis of the model results identified the dominant driver of pre-symptomatic transmission as the contact route via hand-face transfer and showed that wearing masks and avoiding physical contact are an effective prevention strategy. These results provide a sound scientific basis to the present recommendations of the WHO and the CDC.
Combined nanopore and single-molecule real-time sequencing survey of human betaherpesvirus 5 transcriptome
Authors: Kakuk Balázs , Tombácz Dóra , Balázs Zsolt , Moldován Norbert , Csabai Zsolt , Torma Gábor , Megyeri Klára , Snyder Michael , Boldogkői Zsolt 
Published: July 2021

AbstractLong-read sequencing (LRS), a powerful novel approach, is able to read full-length transcripts and confers a major advantage over the earlier gold standard short-read sequencing in the efficiency of identifying for example polycistronic transcripts and transcript isoforms, including transcript length- and splice variants. In this work, we profile the human cytomegalovirus transcriptome using two third-generation LRS platforms: the Sequel from Pacific BioSciences, and MinION from Oxford Nanopore Technologies. We carried out both cDNA and direct RNA sequencing, and applied the LoRTIA software, developed in our laboratory, for the transcript annotations. This study identified a large number of novel transcript variants, including splice isoforms and transcript start and end site isoforms, as well as putative mRNAs with truncated in-frame ORFs (located within the larger ORFs of the canonical mRNAs), which potentially encode N-terminally truncated polypeptides. Our work also disclosed a highly complex meshwork of transcriptional read-throughs and overlaps.