bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Hierarchy of Global Ocean Models Coupled to CESM1
Authors: Hsu Tien‐Yiao , Primeau Francois , Magnusdottir Gudrun 
Published: July 2022

AbstractWe develop a hierarchy of simplified ocean models for coupled ocean, atmosphere, and sea ice climate simulations using the Community Earth System Model version 1 (CESM1). The hierarchy has four members: a slab ocean model, a mixed‐layer model (MLM) with entrainment and detrainment, an Ekman MLM, and an ocean general circulation model (OGCM). Flux corrections of heat and salt are applied to the simplified models ensuring that all hierarchy members have the same climatology. We diagnose the needed flux corrections from auxiliary simulations in which we restore the temperature and salinity to the daily climatology obtained from a target CESM1 simulation. The resulting three‐dimensional corrections contain the interannual variability fluxes that maintain the correct vertical gradients of temperature and salinity in the tropics. We find that the inclusion of mixed‐layer entrainment and Ekman flow produces sea surface temperature and surface air temperature fields whose means and variances are progressively more similar to those produced by the target CESM1 simulation. We illustrate the application of the hierarchy to the problem of understanding the response of the climate system to the loss of Arctic sea ice. We find that the shifts in the positions of the mid‐latitude westerly jet and of the Inter‐tropical Convergence Zone (ITCZ) in response to sea‐ice loss depend critically on upper ocean processes. Specifically, heat uptake associated with the mixed‐layer entrainment influences the shift in the westerly jet and ITCZ. Moreover, the shift of ITCZ is sensitive to the form of Ekman flow parameterization.
Holocene Multi‐Centennial Variations of the Asian Summer Monsoon Triggered by Solar Activity
Authors: Sun Weiyi , Liu Jian , Wang Bin , Chen Deliang , Wan Lingfeng , Wang Jing 
Published: July 2022

AbstractSolar activity affects Asian summer monsoon (ASM) at various time scales. However, it remains unknown if and how solar activity can influence ASM on the centennial time scale. Using the Community Earth System Model, we conduct a solar activity forced Holocene transient simulation with an acceleration factor of 10 and show that during the middle–late Holocene ASM precipitation exhibits a significant 300–600‐year periodicity under solar forcing. This model‐produced multi‐centennial variation is also suggested by proxy data. The leading mode of the multi‐centennial ASM variation shows a “wet tropics–dry subtropics” pattern, which lags the corresponding solar activity by about a quarter cycle. The western North Pacific (WNP) circulation system is responsible for the multi‐centennial ASM variation, through enhancing the climatological south Asia–WNP monsoon trough. We suggest that solar activity modulates the zonal SST gradients of the tropical Pacific, inducing the anomalous WNP cyclone and enhancing ASM precipitation in a delayed mode.
Potential Seismicity Along Basement Faults Induced by Geological Carbon Sequestration
Authors: Chang K. W. , Yoon H. , Martinez M. J. 
Published: July 2022

AbstractLarge‐scale CO2 sequestration into geological formations has been suggested to reduce CO2 emissions from industrial activities. However, much like enhanced geothermal stimulation and wastewater injection, CO2 sequestration has a potential to induce earthquake along weak faults, which can be considered a negative impact on safety and public opinion. This study shows the physical mechanisms of potential seismic hazards along basement faults driven by CO2 sequestration under variation in geological and operational constraints. Specifically we compare the poroelastic behaviors between multiphase flow and single‐phase flow cases, highlighting specific needs of evaluating induced seismicity associated with CO2 sequestration. In contrast to single‐phase injection scenario, slower migration of the CO2 plume than pressure pulse may delay accumulation of pressure and stress along basement faults that may not be mitigated immediately by shut‐in of injection. The impact of multiphase flow system, therefore, needs to be considered for proper monitoring and mitigation strategies.
Neutral Mode Dominates the Forced Global and Regional Surface Temperature Response in the Past and Future
Authors: Liu Fukai , Lu Jian , Leung L. Ruby 
Published: July 2022

AbstractUsing a large suite of Green's function perturbation experiments, we construct the emergent dynamical operator for surface temperature and extract the most excitable mode. The leading mode turns out to be the most dominant mode excited by the climate forcing of doubling CO2, alone capturing 56% of the total spatial variances of the surface temperature response. The pattern of the leading mode is partly organized by the atmospheric annular modes in both hemispheres, and further modulated by the feedbacks from ocean circulations. Though derived from a single model, the leading mode can capture the spatio‐temporal variabilities of the global mean surface temperature over the past century in both the CMIP6 model simulations and observations. Moreover, the leading mode is most efficiently excited by radiative forcings from the midlatitude bands centered around 45°N and 25°S, where most human activities take place, suggesting the potency of human influence on the climate change.
First Experimental Verification of Opacity for the Lightning Near‐Infrared Spectrum
Authors: Wang Xuejuan , Wang Haitong , Lyu Weitao , Chen Lyuwen , Ma Ying , Qi Qi , Wu Bin , Xu Weiqun , Hua Leyan , Yang Jing , Wang Jinhu 
Published: July 2022

AbstractUsing the spectral data of a lightning continuing discharge process observed on the 600‐m‐high Canton Tower, experimental verification of the optical thickness of lightning neutral nitrogen (NI) and neutral oxygen (OI) radiation in the near‐infrared spectrum is presented first by comparing the measured relative intensities of two NI multiplets with theoretical values. For the first time, the spectral evolution characteristics of the tall structure lightning continuing discharge process show that visible band singly ionized lines were apparent for approximately 320–400 µs. The ionized lines with higher excitation energies and the neutral lines with lower excitation energies coexist for approximately 240–320 µs, which means that there is a hot region radiating ionized lines in a radial direction from the lightning channel, but at the same time there is also a cold region radiating neutral lines.
Multi‐Pulse Corona Discharges in Thunderclouds Observed in Optical and Radio Bands
Authors: Li Dongshuai , Luque Alejandro , Lehtinen Nikolai G. , Gordillo‐Vázquez F. J. , Neubert Torsten , Lu Gaopeng , Chanrion Olivier , Zhang Hongbo , Østgaard Nikolai , Reglero Víctor 
Published: July 2022

AbstractHow lightning initiates inside thunderclouds remains a major puzzle of atmospheric electricity. By monitoring optical emissions from thunderstorms, the Atmosphere‐Space Interactions Monitor (ASIM) onboard the International Space Station is providing new clues about lightning initiation by detecting Blue LUminous Events (BLUEs), which are manifestations of electrical corona discharges that sometimes precedes lightning. Here we combine optical and radio observations from a thunderstorm near Malaysia to uncover a new type of event containing multiple optical and radio pulses. We find that the first optical pulse coincides with a strong radio signal in the form of a Narrow Bipolar Event (NBE) but subsequent optical pulses, delayed some milliseconds, have weaker radio signals, possibly because they emanate from a horizontally oriented electrical discharges which does not trigger full‐fledged lightning. Our results cast light on the differences between isolated and lightning‐initiating electrical discharges.
A Small Peak in the Swarm‐LP Plasma Density Data at the Dayside Dip Equator
Authors: Song Hosub , Park Jaeheung , Buchert Stephan , Jin Yaqi , Chao Chi Kuang , Lee Jaejin , Yi Yu 
Published: July 2022

AbstractIn this paper, we statistically investigate an artifact in Langmuir Probe (LP) observations of Swarm satellites. A small peak of electron density (Ne) is frequently found in the Swarm data around the dayside dip equator. On the contrary, they appear in neither the Total Electron Content data of the Swarm/Global Positioning System Receivers nor COSMIC‐2 in‐situ measurements at similar altitudes but with low orbit inclination. Arguably, this peak does not represent natural ionospheric irregularities but is likely to result from artifacts. The phenomena are found regardless of the season, solar activity, and the velocity direction of the satellite (ascending and descending). They predominantly occur when the magnetic declination is close to zero, that is, when the Swarm ram direction and the Earth's magnetic field are aligned under sunlight. Hence, we attribute the phenomenon to intensified secondary electrons escape when the geomagnetic field lines are normal to conducting surfaces that emit secondary electrons. Since the magnitude of the artifact is only a few percent of the large‐scale background, it does not have a serious impact on the value of the Swarm/LP data in scientific research. Nevertheless, future efforts to determine the exact cause of the artifacts will contribute to improving the reliability and quality of plasma density and temperature measured by Swarm/LP.
The Representation of Spiral Gravity Waves in a Mesoscale Model With Increasing Horizontal and Vertical Resolution
Authors: Nolan David S. , Onderlinde Matthew J. 
Published: July 2022

AbstractRecent observational and numerical studies have investigated the dynamics of fine‐scale gravity waves radiating horizontally outward from tropical cyclones. The waves are wrapped into spirals by the tangential wind of the cyclone and are described as spiral gravity waves. This study addresses how well numerical simulations of these waves compare to observations as the horizontal grid spacing is decreased from 2.0 to 1.0 to 0.5 km, and the number of vertical levels changes from 25 to 50 to 100. Spectral filtering is applied to separate the fine‐scale waves in vertical velocity (w) and the larger‐scale waves in pressure (p) from moist updrafts and downdrafts in the eyewall and rainbands. As the grid spacing decreases, the radial wavelengths of the w waves decrease from 20 to 7 km, approaching observed values. For grid spacing 1.0 km, the p waves become well‐resolved with wavelength 70 km. The outward phase speeds range from 15 to 30 ms−1 for the w waves and 50 to 70 ms−1 for p waves. Analysis of the upper‐level outflow region finds that the spiral w waves propagate 5–10 ms−1 faster due to radial advection, but also finds what appear to be different classes of larger‐amplitude, slow‐moving spiral waves. Similar waves can be seen in satellite images, which appear to be caused by dynamical instability of the strongly vertically sheared radial and tangential winds in the TC outflow.
LIN28B inhibition sensitizes cells to p53-restoring PPI therapy through unleashed translational suppression
Authors: Shi Jiahao , Jin Xiaoliang , Wang Yihao , Zhu Tianyu , Zhang Dongmei , Li Qian , Zhong Xiaomin , Deng Yaqi , Shen Jianfeng , Fan Xianqun 
Published: July 2022

Abstractp53 is the most highly mutated tumor suppressor across multiple types of human cancers. The level and function of p53 are fine-tuned through multifaced mechanisms in which the protein–protein interaction between p53 and MDM2 is considered as a major circuit. Recent studies suggest therapeutic strategy attempts to restore p53 function by small molecule inhibitors targeting p53–MDM2 interaction can be a promising direction in treating cancers with wild-type or functional p53. Currently, clinical tests of the p53–MDM2 protein–protein interaction inhibitors (PPIs) are underway. However, it remains elusive about the biomarkers that may predict the therapeutic responses to those inhibitors. Here we report that RNA-binding protein LIN28B directly regulates p53 through binding to the 5′΄ untranslated region of p53 mRNA and blocks its translation by competing with a translation enhancer protein, ribosomal protein L26 (RPL26). This regulatory mechanism of LIN28B does not involve let-7 maturation or the canonical protein turnover pathway of p53. Furthermore, we show that inhibition of LIN28B unleashes the translational suppression of p53 through RPL26, and leads to enhanced sensitivities of cancer cells to inhibitors of p53–MDM2 interaction. Together, we demonstrate a competitive regulatory mechanism of p53 by LIN28B, which has important implications in developing biomarkers to the therapies aiming to reinstate p53 function.
The clinically relevant CYP2C8*3 and CYP2C9*2 haplotype is inherited from Neandertals
Authors: Haeggström Sigrid , Ingelman-Sundberg Magnus , Pääbo Svante , Zeberg Hugo 
Published: July 2022

AbstractGenetic variation in genes encoding cytochrome P450 enzymes influences the metabolism of drugs and endogenous compounds. The locus containing the cytochrome genes CYP2C8 and CYP2C9 on chromosome 10 exhibits linkage disequilibrium between the CYP2C8*3 and CYP2C9*2 alleles, forming a haplotype of ~300 kilobases. This haplotype is associated with altered metabolism of several drugs, most notably reduced metabolism of warfarin and phenytoin, leading to toxicity at otherwise therapeutic doses. Here we show that this haplotype is inherited from Neandertals.
Investigation of the monopole magneto-chemical potential in spin ices using capacitive torque magnetometry
Authors: Anand Naween , Barry Kevin , Neu Jennifer N. , Graf David E. , Huang Qing , Zhou Haidong , Siegrist Theo , Changlani Hitesh J. , Beekman Christianne 
Published: July 2022

AbstractThe single-ion anisotropy and magnetic interactions in spin-ice systems give rise to unusual non-collinear spin textures, such as Pauling states and magnetic monopoles. The effective spin correlation strength (Jeff) determines the relative energies of the different spin-ice states. With this work, we display the capability of capacitive torque magnetometry in characterizing the magneto-chemical potential associated with monopole formation. We build a magnetic phase diagram of Ho2Ti2O7, and show that the magneto-chemical potential depends on the spin sublattice (α or β), i.e., the Pauling state, involved in the transition. Monte Carlo simulations using the dipolar-spin-ice Hamiltonian support our findings of a sublattice-dependent magneto-chemical potential, but the model underestimates the Jeff for the β-sublattice. Additional simulations, including next-nearest neighbor interactions (J2), show that long-range exchange terms in the Hamiltonian are needed to describe the measurements. This demonstrates that torque magnetometry provides a sensitive test for Jeff and the spin-spin interactions that contribute to it.
Anti-dissolution Pt single site with Pt(OH)(O3)/Co(P) coordination for efficient alkaline water splitting electrolyzer
Authors: Zeng Lingyou , Zhao Zhonglong , Lv Fan , Xia Zhonghong , Lu Shi-Yu , Li Jiong , Sun Kaian , Wang Kai , Sun Yingjun , Huang Qizheng , Chen Yan , Zhang Qinghua , Gu Lin , Lu Gang , Guo Shaojun 
Published: July 2022

AbstractAs the most well-known electrocatalyst for cathodic hydrogen evolution in water splitting electrolyzers, platinum is unfortunately inefficient for anodic oxygen evolution due to its over-binding with oxygen species and excessive dissolution in oxidative environment. Herein we show that single Pt atoms dispersed in cobalt hydrogen phosphate with an unique Pt(OH)(O3)/Co(P) coordination can achieve remarkable catalytic activity and stability for oxygen evolution. The catalyst yields a high turnover frequency (35.1 ± 5.2 s−1) and mass activity (69.5 ± 10.3 A mg−1) at an overpotential of 300 mV and excellent stability. Mechanistic studies elucidate that the superior catalytic performance of isolated Pt atoms herein stems from optimal binding energies of oxygen intermediate and also their strong electronic coupling with neighboring Co atoms that suppresses the formation of soluble Ptx>4 species. Alkaline water electrolyzers assembled with an ultralow Pt loading realizes an industrial-level current density of 1 A cm−2 at 1.8 volts with a high durability.
Synthesis and direct assay of large macrocycle diversities by combinatorial late-stage modification at picomole scale
Authors: Habeshian Sevan , Merz Manuel Leonardo , Sangouard Gontran , Mothukuri Ganesh Kumar , Schüttel Mischa , Bognár Zsolt , Díaz-Perlas Cristina , Vesin Jonathan , Bortoli Chapalay Julien , Turcatti Gerardo , Cendron Laura , Angelini Alessandro , Heinis Christian 
Published: July 2022

AbstractMacrocycles have excellent potential as therapeutics due to their ability to bind challenging targets. However, generating macrocycles against new targets is hindered by a lack of large macrocycle libraries for high-throughput screening. To overcome this, we herein established a combinatorial approach by tethering a myriad of chemical fragments to peripheral groups of structurally diverse macrocyclic scaffolds in a combinatorial fashion, all at a picomole scale in nanoliter volumes using acoustic droplet ejection technology. In a proof-of-concept, we generate a target-tailored library of 19,968 macrocycles by conjugating 104 carboxylic-acid fragments to 192 macrocyclic scaffolds. The high reaction efficiency and small number of side products of the acylation reactions allowed direct assay without purification and thus a large throughput. In screens, we identify nanomolar inhibitors against thrombin (Ki = 44 ± 1 nM) and the MDM2:p53 protein-protein interaction (Kd MDM2 = 43 ± 18 nM). The increased efficiency of macrocycle synthesis and screening and general applicability of this approach unlocks possibilities for generating leads against any protein target.
Electroredox carbene organocatalysis with iodide as promoter
Authors: Zhou Peng , Li Wenchang , Lan Jianyong , Zhu Tingshun 
Published: July 2022

AbstractOxidative carbene organocatalysis, inspired from Vitamin B1 catalyzed oxidative activation from pyruvate to acetyl coenzyme A, have been developed as a versatile synthetic method. To date, the α-, β-, γ-, δ- and carbonyl carbons of (unsaturated)aldehydes have been successfully activated via oxidative N-heterocyclic carbene (NHC) organocatalysis. In comparison with chemical redox or photoredox methods, electroredox methods, although widely used in mechanistic study, were much less developed in NHC catalyzed organic synthesis. Herein, an iodide promoted electroredox NHC organocatalysis system was developed. This system provided general solutions for electrochemical single-electron-transfer (SET) oxidation of Breslow intermediate towards versatile transformations. Radical clock experiment and cyclic voltammetry results suggested an anodic radical coupling pathway.
Single-molecule FRET uncovers hidden conformations and dynamics of human Argonaute 2
Authors: Willkomm Sarah , Jakob Leonhard , Kramm Kevin , Graus Veronika , Neumeier Julia , Meister Gunter , Grohmann Dina 
Published: July 2022

AbstractHuman Argonaute 2 (hAgo2) constitutes the functional core of the RNA interference pathway. Guide RNAs direct hAgo2 to target mRNAs, which ultimately leads to hAgo2-mediated mRNA degradation or translational inhibition. Here, we combine site-specifically labeled hAgo2 with time-resolved single-molecule FRET measurements to monitor conformational states and dynamics of hAgo2 and hAgo2-RNA complexes in solution that remained elusive so far. We observe dynamic anchoring and release of the guide’s 3’-end from the PAZ domain during the stepwise target loading process even with a fully complementary target. We find differences in structure and dynamic behavior between partially and fully paired canonical hAgo2-guide/target complexes and the miRNA processing complex formed by hAgo2 and pre-miRNA451. Furthermore, we detect a hitherto unknown conformation of hAgo2-guide/target complexes that poises them for target-directed miRNA degradation. Taken together, our results show how the conformational flexibility of hAgo2-RNA complexes determines function and the fate of the ribonucleoprotein particle.
The megabase-scale crossover landscape is largely independent of sequence divergence
Authors: Lian Qichao , Solier Victor , Walkemeier Birgit , Durand Stéphanie , Huettel Bruno , Schneeberger Korbinian , Mercier Raphael 
Published: July 2022

AbstractMeiotic recombination frequency varies along chromosomes and strongly correlates with sequence divergence. However, the causal relationship between recombination landscapes and polymorphisms is unclear. Here, we characterize the genome-wide recombination landscape in the quasi-absence of polymorphisms, usingArabidopsis thalianahomozygous inbred lines in which a few hundred genetic markers were introduced through mutagenesis. We find that megabase-scale recombination landscapes in inbred lines are strikingly similar to the recombination landscapes in hybrids, with the notable exception of heterozygous large rearrangements where recombination is prevented locally. In addition, the megabase-scale recombination landscape can be largely explained by chromatin features. Our results show that polymorphisms are not a major determinant of the shape of the megabase-scale recombination landscape but rather favour alternative models in which recombination and chromatin shape sequence divergence across the genome.
Green gentrification in European and North American cities
Authors: Anguelovski Isabelle , Connolly James J. T. , Cole Helen , Garcia-Lamarca Melissa , Triguero-Mas Margarita , Baró Francesc , Martin Nicholas , Conesa David , Shokry Galia , del Pulgar Carmen Pérez , Ramos Lucia Argüelles , Matheney Austin , Gallez Elsa , Oscilowicz Emilia , Máñez Jésua López , Sarzo Blanca , Beltrán Miguel Angel , Minaya Joaquin Martinez 
Published: July 2022

AbstractAlthough urban greening is universally recognized as an essential part of sustainable and climate-responsive cities, a growing literature on green gentrification argues that new green infrastructure, and greenspace in particular, can contribute to gentrification, thus creating social and racial inequalities in access to the benefits of greenspace and further environmental and climate injustice. In response to limited quantitative evidence documenting the temporal relationship between new greenspaces and gentrification across entire cities, let alone across various international contexts, we employ a spatially weighted Bayesian model to test the green gentrification hypothesis across 28 cities in 9 countries in North America and Europe. Here we show a strong positive and relevant relationship for at least one decade between greening in the 1990s–2000s and gentrification that occurred between 2000–2016 in 17 of the 28 cities. Our results also determine whether greening plays a “lead”, “integrated”, or “subsidiary” role in explaining gentrification.