bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stable Carbon Isotope Studies of CH4 Dynamics Via Water and Plant Pathways in a Tropical Thai Paddy: Insights Into Diel CH4 Transportation
Authors: Komiya Shujiro , Yazaki Tomotsugu , Kondo Fumiyoshi , Katano Kentaro , Lavric Jost V. , McTaggart Iain , Pakoktom Tiwa , Siangliw Meechai , Toojinda Theerayut , Noborio Kosuke 
Published: August 2020

AbstractSeparate evaluation of methane (CH4) emission dynamics (e.g., oxidation, production, and transportation) at the soil‐plant‐atmosphere and soil‐water‐atmosphere interfaces has been limited in tropical rice paddies, but it is crucial for comprehending the entire CH4 cycles. We investigated CH4 oxidation, production, and transportation through plant and water pathways during the reproductive stage in a tropical Thailand rice paddy field using natural abundance carbon stable isotope ratios (δ13CH4 and δ13CO2). Mass balance equations using δ13CH4 and δ13CO2 in soil gases indicated that CH4 oxidation in the planted soil exceeded those in the interrow soil due to oxygen supply through rice roots. In addition, at 1–11 cm depth acetate fermentation was the dominant process in the planted soil, whereas in the interrow soil the dominant process was H2/CO2 reduction. The water pathway showed a significant negative correlation between CH4 flux and released δ13CH4 over 24 hr, driven by a diel change in episodic ebullition, steady ebullition, and diffusion, all due to diel changes in soil temperature and atmospheric pressure. In contrast, the plant pathway showed a significant positive relationship between CH4 flux and emitted δ13CH4 throughout one day. A comparison of the diel change in emitted δ13CH4 between the water and plant pathways showed that the rice plants transported CH4 in soil bubbles without any large isotopic fractionation. The diel change in the plant‐mediated CH4 transportation was mainly controlled by diel changes in soil bubble expansion and CH4 diffusion through plants, which were probably regulated by diel changes in soil temperature and atmospheric pressure.
Simulations for CMIP6 With the AWI Climate Model AWI‐CM‐1‐1
Authors: Semmler Tido , Danilov Sergey , Gierz Paul , Goessling Helge F. , Hegewald Jan , Hinrichs Claudia , Koldunov Nikolay , Khosravi Narges , Mu Longjiang , Rackow Thomas , Sein Dmitry V. , Sidorenko Dmitry , Wang Qiang , Jung Thomas 
Published: August 2020

AbstractThe Alfred Wegener Institute Climate Model (AWI‐CM) participates for the first time in the Coupled Model Intercomparison Project (CMIP), CMIP6. The sea ice‐ocean component, FESOM, runs on an unstructured mesh with horizontal resolutions ranging from 8 to 80 km. FESOM is coupled to the Max Planck Institute atmospheric model ECHAM 6.3 at a horizontal resolution of about 100 km. Using objective performance indices, it is shown that AWI‐CM performs better than the average of CMIP5 models. AWI‐CM shows an equilibrium climate sensitivity of 3.2°C, which is similar to the CMIP5 average, and a transient climate response of 2.1°C which is slightly higher than the CMIP5 average. The negative trend of Arctic sea‐ice extent in September over the past 30 years is 20–30% weaker in our simulations compared to observations. With the strongest emission scenario, the AMOC decreases by 25% until the end of the century which is less than the CMIP5 average of 40%. Patterns and even magnitude of simulated temperature and precipitation changes at the end of this century compared to present‐day climate under the strong emission scenario SSP585 are similar to the multi‐model CMIP5 mean. The simulations show a 11°C warming north of the Barents Sea and around 2°C to 3°C over most parts of the ocean as well as a wetting of the Arctic, subpolar, tropical, and Southern Ocean. Furthermore, in the northern middle latitudes in boreal summer and autumn as well as in the southern middle latitudes, a more zonal atmospheric flow is projected throughout the year.
Solute Production and Transport Processes in Chinese Monsoonal Rivers: Implications for Global Climate Change
Authors: Zhong Jun , Li Si‐Liang , Ibarra Daniel E. , Ding Hu , Liu Cong‐Qiang 
Published: August 2020

AbstractThe negative feedback between chemical weathering and climate is hypothesized to act as an important control on modulating atmospheric CO2 over geologic timescales, affecting the evolution of Earth's climate over the history of Earth. Here, we investigated solute production processes by analyzing concentration‐discharge, denoted here as concentration‐runoff (C‐q), relationships of Chinese monsoonal rivers, through both the empirical power law relationship and a recently developed Solute Production Model. We found that solute concentrations were highly modulated by hydrologic conditions which shifted the Damköhler number, Da, the ratio of fluid transit time versus the time required to reach equilibrium. Additionally, the among‐catchment behavior of HCO3− responding to changing runoff was correlated with the average Da of each catchment. Rivers with high average Da induced high maximum weathering fluxes, while the maximum weathering potential was primarily controlled by the Damköhler coefficient (Dw, m/yr), the reactivity of the material in the weathering zone over a given length scale, among the catchments in this study. Globally, HCO3− behaviors and weathering characteristics are highly influenced by carbonate bedrock distributions and abundance. In addition, Chinese monsoonal rivers have higher weathering fluxes, weathering potential, and climate‐weathering feedback sensitivity (4.4%/°C) than most other global rivers. Our work disclosed the mechanisms that link runoff, lithology, and weathering fluxes in monsoonal rivers and analyzed the controlling factors on solute dynamics on global scale, which can be implemented in exploring the chemical weathering processes under ongoing global climate change.
On the Performance of Sentinel‐3 Altimetry Over New Reservoirs: Approaches to Determine Onboard A Priori Elevation
Authors: Zhang Xingxing , Jiang Liguang , Kittel Cécile M. M. , Yao Zhijun , Nielsen Karina , Liu Zhaofei , Wang Rui , Liu Jun , Andersen Ole B. , Bauer‐Gottwein Peter 
Published: August 2020

AbstractSatellite radar altimetry has become an important data source supplementing in situ water level. For practical reasons, a radar altimeter can only record reflected echoes within its range window. Therefore, water surface elevation must fall within the range window. To this end, the Sentinel‐3 radar altimetry mission is configured with a new tracking function (i.e., open loop) to position its range window based on an onboard a priori elevation of ground targets. We found that Sentinel‐3 is unable to observe recently built reservoirs due to the incorrect onboard elevations. To overcome this issue, four approaches are proposed to improve the a priori elevation for inland water bodies, particularly reservoirs. These approaches can significantly increase data availability of Sentinel‐3 over reservoirs and can be used to prepare the onboard elevations of reservoirs and lakes for future missions such as Sentinel‐6, Sentinel‐3C/‐3D, and the Surface Water and Ocean Topography (SWOT) mission.
Magnetic Reconnection in the Ionosphere of Mars: The Role of Collisions
Authors: Cravens T. E. , Fowler C. M. , Brain D. , Rahmati A. , Xu S. , Ledvina S. A. , Andersson L. , Renzaglia A. R. 
Published: August 2020

AbstractThis paper evaluates the role of magnetic reconnection in the dayside ionosphere of Mars in the collisional regime and presents some relevant data from the MAVEN (Mars Atmosphere and Volatile EvolutioN) mission. Magnetic reconnection is an important process operating in the solar corona, planetary magnetospheres, and astrophysical plasmas, but most of the literature focuses on collisionless plasmas. However, at Mars the reconnection should often occur in regions where collisions are important. Mars does not have a large‐scale global magnetic field; however, Mars has locally large magnetic fields associated with remnant crustal magnetization, particularly in the highland regions of the southern hemisphere. The crustal fields provide a “target” for reconnection both in the ionosphere and in the magnetotail of Mars. The current paper emphasizes the dayside ionosphere. Magnetic reconnection is associated with topological changes in the magnetic field and is also a source of energy for the plasma and can thus affect the ionospheric dynamics and ion loss at Mars. Both theoretical concepts and MAVEN particle and field data from several instruments are considered in this paper.
Enhancing the Noah‐MP Ecosystem Response to Droughts With an Explicit Representation of Plant Water Storage Supplied by Dynamic Root Water Uptake
Authors: Niu Guo‐Yue , Fang Yuan‐Hao , Chang Li‐Ling , Jin Jiming , Yuan Hua , Zeng Xubin 
Published: August 2020

AbstractPlants are able to adapt to changing environments and thus survive droughts. However, most land surface models produce unrealistically low ecosystem resiliency to droughts, degrading the credibility of the model‐predicted ecohydrological responses to climate change. We aim to enhance the Noah‐MP modeled ecosystem resilience to droughts with an explicit representation of plant water storage supplied by dynamic root water uptake through hydrotropic root growth to meet the transpiration demand. The new model represents plant stomatal water stress factor as a function of the plant water storage and relates the rate of root water uptake to the profile of model‐predicted root surface area. Through optimization of major leaf, root, and soil parameters, the new model improves the prediction of leaf area index, ecosystem productivity, evapotranspiration, and terrestrial water storage variations over most basins in the contiguous United States. Sensitivity experiments suggest that both dynamic root water uptake and groundwater capillary rise extend the plants' “memory” of antecedent rainfall. The modeled plants enhance their efficiency to use antecedent rain water stored in shallow soils mainly through more efficient root water uptake over the U.S. Southwest drylands while use that stored in deep soils and aquifers with the aid of groundwater capillary rise in the Central United States. Future plant hydraulic models should not ignore soil water retention model uncertainties and the soil macropore effects on soil water potential and infiltration.
Historical, Philosophical, and Sociological Perspectives on Earth System Modeling
Authors: Rödder Simone , Heymann Matthias , Stevens Bjorn 
Published: August 2020

AbstractWith the advent of climate change as a major challenge of our time, Earth system modeling has become highly policy‐relevant regulatory science. In this situation, the social mechanisms that play a role in any scientific endeavor become particularly exposed. By discussing historical, philosophical, and sociological (HPS) aspects of the field's current “cultures of prediction” together with the physical science community in a physical science journal, we aim to provide an entry point into HPS reasoning for climate scientists interested in reflecting on their field and science in general. This paper, first, introduces our perspective on “science as culture” and climate modeling as “regulatory science” and, second, highlights and connects relevant ideas from the three commentaries that follow it. In so doing, we hope to give a fuller picture of climate science, the interplay it engenders between HPS and the physical sciences, the distinctions that it gives rise to as compared to some of the more traditional, exact, sciences in which it is rooted and its place in society including its role in scientific policy advice.
Climate‐Induced Variability in Mediterranean Outflow to the North Atlantic Ocean During the Late Pleistocene
Authors: Nichols Matthew D. , Xuan Chuang , Crowhurst Simon , Hodell David A. , Richter Carl , Acton Gary D. , Wilson Paul A. 
Published: August 2020

AbstractMediterranean Outflow Water (MOW) adds salt and density to open ocean intermediate waters and is therefore an important motor of Atlantic meridional overturning circulation (AMOC) and climate variability. However, the variability in strength and depth of MOW on geological timescales is poorly documented. Here we present new detailed records, with excellent age control, of MOW variability from 416 ka to present from rapidly accumulated marine sediments recovered from the West Iberian Margin during Integrated Ocean Drilling Program (IODP) Expedition 339. Our records of X‐ray fluorescence (XRF), physical grain size, and paleocurrent information from the anisotropy of magnetic susceptibility (AMS) indicate (i) a close relationship between the orientation of principle AMS axes and glacial‐interglacial cycles and (ii) two distinct regimes of MOW behavior over the last ~416 kyr in grain‐size and AMS variability at orbital (mainly precessional) and suborbital timescales. Between marine isotope stage (MIS) 10 and MIS 4, MOW was focused at a generally shallow depth on the West Iberian Margin, and changes in MOW strength were strongly paced by precession. A transition interval occurred during MISs 5 and 4, when MOW deepened and millennial‐scale variability in flow strength was superimposed on orbitally paced change. During MIS 11 and from MIS 3 to present, MOW was deeply focused and millennial‐scale variability dominated. We infer that late Pleistocene variability in MOW strength and depth were strongly climate influenced and that changes in circum‐Mediterranean rainfall climate were likely a primary control.
Impact Forecasting to Support Emergency Management of Natural Hazards
Authors: Merz Bruno , Kuhlicke Christian , Kunz Michael , Pittore Massimiliano , Babeyko Andrey , Bresch David N. , Domeisen Daniela I. V. , Feser Frauke , Koszalka Inga , Kreibich Heidi , Pantillon Florian , Parolai Stefano , Pinto Joaquim G. , Punge Heinz Jürgen , Rivalta Eleonora , Schröter Kai , Strehlow Karen , Weisse Ralf , Wurpts Andreas 
Published: August 2020

AbstractForecasting and early warning systems are important investments to protect lives, properties, and livelihood. While early warning systems are frequently used to predict the magnitude, location, and timing of potentially damaging events, these systems rarely provide impact estimates, such as the expected amount and distribution of physical damage, human consequences, disruption of services, or financial loss. Complementing early warning systems with impact forecasts has a twofold advantage: It would provide decision makers with richer information to take informed decisions about emergency measures and focus the attention of different disciplines on a common target. This would allow capitalizing on synergies between different disciplines and boosting the development of multihazard early warning systems. This review discusses the state of the art in impact forecasting for a wide range of natural hazards. We outline the added value of impact‐based warnings compared to hazard forecasting for the emergency phase, indicate challenges and pitfalls, and synthesize the review results across hazard types most relevant for Europe.
A Phase 1 dose-escalation study to evaluate safety, pharmacokinetics and pharmacodynamics of AsiDNA, a first-in-class DNA repair inhibitor, administered intravenously in patients with advanced solid tumours
Authors: Le Tourneau Christophe , Delord Jean-Pierre , Kotecki Nuria , Borcoman Edith , Gomez-Roca Carlos , Hescot Ségolène , Jungels Christiane , Vincent-Salomon Anne , Cockenpot Vincent , Eberst Lauriane , Molé Audrey , Jdey Wael , Bono Françoise , Trochon-Joseph Véronique , Toussaint Hélène , Zandanel Christelle , Adamiec Olga , de Beaumont Olivier , Cassier Philippe Alexandre 
Published: August 2020

AbstractBackgroundAsiDNA, a first-in-class oligonucleotide-mimicking double-stranded DNA breaks, acts as a decoy agonist to DNA damage response in tumour cells. It also activates DNA-dependent protein kinase and poly (adenosine diphosphate [ADP]-ribose) polymerase enzymes that induce phosphorylation of H2AX and protein PARylation.MethodsThe aim of this Phase 1 study was to determine dose-limiting toxicities (DLTs), maximum tolerated dose (MTD), safety and pharmacokinetics/pharmacodynamics of AsiDNA administered daily for 3 days in the first week then weekly thereafter. Twenty-two patients with advanced solid tumours were enrolled in 5 dose levels: 200, 400, 600, 900, and 1300 mg, using a 3 + 3 design.ResultsThe MTD was not reached. IV AsiDNA was safe. Two DLTs (grade 4 and grade 3 hepatic enzymes increased at 900 and 1300 mg), and two related SAE at 900 mg (grade 3 hypotension and grade 4 hepatic enzymes increased) were reported. AsiDNA PK increased proportionally with dose. A robust activation of DNA-PK by a significant posttreatment increase of γH2AX was evidenced in tumour biopsies.ConclusionThe dose of 600 mg was identified as the optimal dose for further clinical development.Clinical trial registrationClinical trial registration (NCT number): NCT03579628.
Regulation of epithelial-mesenchymal transition and organoid morphogenesis by a novel TGFβ-TCF7L2 isoform-specific signaling pathway
Authors: Karve Kunal , Netherton Stuart , Deng Lili , Bonni Azad , Bonni Shirin 
Published: August 2020

AbstractAlternative splicing contributes to diversification of gene function, yet consequences of splicing on functions of specific gene products is poorly understood. The major transcription factor TCF7L2 undergoes alternative splicing but the biological significance of TCF7L2 isoforms has remained largely to be elucidated. Here, we find that the TCF7L2 E-isoforms maintain, whereas the M and S isoforms disrupt morphogenesis of 3D-epithelial cell-derived organoids via regulation of epithelial-mesenchymal transition (EMT). Remarkably, TCF7L2E2 antagonizes, whereas TCF7L2M2/S2 promotes EMT-like effects in epithelial cells induced by transforming growth factor beta (TGFβ) signaling. In addition, we find TGFβ signaling reduces the proportion of TCF7L2E to TCF7L2M/S protein in cells undergoing EMT. We also find that TCF7L2 operates via TGFβ-Smad3 signaling to regulate EMT. Collectively, our findings unveil novel isoform-specific functions for the major transcription factor TCF7L2 and provide novel links between TCF7L2 and TGFβ signaling in the control of EMT-like responses and epithelial tissue morphogenesis.
Probing the active site in single-atom oxygen reduction catalysts via operando X-ray and electrochemical spectroscopy
Authors: Lien Hsiang-Ting , Chang Sun-Tang , Chen Po-Tuan , Wong Deniz P. , Chang Yu-Chung , Lu Ying-Rei , Dong Chung-Li , Wang Chen-Hao , Chen Kuei-Hsien , Chen Li-Chyong 
Published: August 2020

AbstractNonnoble metal catalysts are low-cost alternatives to Pt for the oxygen reduction reactions (ORRs), which have been studied for various applications in electrocatalytic systems. Among them, transition metal complexes, characterized by a redox-active single-metal-atom with biomimetic ligands, such as pyrolyzed cobalt–nitrogen–carbon (Co–Nx/C), have attracted considerable attention. Therefore, we reported the ORR mechanism of pyrolyzed Vitamin B12 using operando X-ray absorption spectroscopy coupled with electrochemical impedance spectroscopy, which enables operando monitoring of the oxygen binding site on the metal center. Our results revealed the preferential adsorption of oxygen at the Co2+ center, with end-on coordination forming a Co2+-oxo species. Furthermore, the charge transfer mechanism between the catalyst and reactant enables further Co–O species formation. These experimental findings, corroborated with first-principle calculations, provide insight into metal active-site geometry and structural evolution during ORR, which could be used for developing material design strategies for high-performance electrocatalysts for fuel cell applications.
A broad-spectrum virus- and host-targeting peptide against respiratory viruses including influenza virus and SARS-CoV-2
Authors: Zhao Hanjun , To Kelvin K. W. , Sze Kong-Hung , Yung Timothy Tin-Mong , Bian Mingjie , Lam Hoiyan , Yeung Man Lung , Li Cun , Chu Hin , Yuen Kwok-Yung 
Published: August 2020

AbstractThe 2019 novel respiratory virus (SARS-CoV-2) causes COVID-19 with rapid global socioeconomic disruptions and disease burden to healthcare. The COVID-19 and previous emerging virus outbreaks highlight the urgent need for broad-spectrum antivirals. Here, we show that a defensin-like peptide P9R exhibited potent antiviral activity against pH-dependent viruses that require endosomal acidification for virus infection, including the enveloped pandemic A(H1N1)pdm09 virus, avian influenza A(H7N9) virus, coronaviruses (SARS-CoV-2, MERS-CoV and SARS-CoV), and the non-enveloped rhinovirus. P9R can significantly protect mice from lethal challenge by A(H1N1)pdm09 virus and shows low possibility to cause drug-resistant virus. Mechanistic studies indicate that the antiviral activity of P9R depends on the direct binding to viruses and the inhibition of virus-host endosomal acidification, which provides a proof of concept that virus-binding alkaline peptides can broadly inhibit pH-dependent viruses. These results suggest that the dual-functional virus- and host-targeting P9R can be a promising candidate for combating pH-dependent respiratory viruses.
Spatially selective manipulation of cells with single-beam acoustical tweezers
Authors: Baudoin Michael , Thomas Jean-Louis , Sahely Roudy Al , Gerbedoen Jean-Claude , Gong Zhixiong , Sivery Aude , Matar Olivier Bou , Smagin Nikolay , Favreau Peter , Vlandas Alexis 
Published: August 2020

AbstractAcoustical tweezers open major prospects in microbiology for cells and microorganisms contactless manipulation, organization and mechanical properties testing since they are biocompatible, label-free and have the potential to exert forces several orders of magnitude larger than their optical counterpart at equivalent power. Yet, these perspectives have so far been hindered by the absence of spatial selectivity of existing acoustical tweezers - i.e., the ability to select and move objects individually - and/or their limited resolution restricting their use to large particle manipulation only and/or finally the limited forces that they could apply. Here, we report precise selective manipulation and positioning of individual human cells in a standard microscopy environment with trapping forces up to ~200 pN without altering their viability. These results are obtained with miniaturized acoustical tweezers combining holography with active materials to synthesize specific wavefields called focused acoustical vortices designed to produce stiff localized traps with reduced acoustic power.
Different scaling of linear models and deep learning in UKBiobank brain images versus machine-learning datasets
Authors: Schulz Marc-Andre , Yeo B. T. Thomas , Vogelstein Joshua T. , Mourao-Miranada Janaina , Kather Jakob N. , Kording Konrad , Richards Blake , Bzdok Danilo 
Published: August 2020

AbstractRecently, deep learning has unlocked unprecedented success in various domains, especially using images, text, and speech. However, deep learning is only beneficial if the data have nonlinear relationships and if they are exploitable at available sample sizes. We systematically profiled the performance of deep, kernel, and linear models as a function of sample size on UKBiobank brain images against established machine learning references. On MNIST and Zalando Fashion, prediction accuracy consistently improves when escalating from linear models to shallow-nonlinear models, and further improves with deep-nonlinear models. In contrast, using structural or functional brain scans, simple linear models perform on par with more complex, highly parameterized models in age/sex prediction across increasing sample sizes. In sum, linear models keep improving as the sample size approaches ~10,000 subjects. Yet, nonlinearities for predicting common phenotypes from typical brain scans remain largely inaccessible to the examined kernel and deep learning methods.