bluuebunny/crossref_metadata_2025_split huggingface dataset:
Revisiting AMOC Transport Estimates From Observations and Models
Authors: Danabasoglu Gokhan , Castruccio Frederic S. , Small R. Justin , Tomas Robert , Frajka‐Williams Eleanor , Lankhorst Matthias 
Published: May 2021

AbstractReference level assumptions used to calculate the Atlantic meridional overturning circulation transports at the RAPID and Meridional Overturning Variability Experiment (MOVE) observing arrays are revisited in an eddying ocean model. Observational transport calculation methods are complemented by several alternative approaches. At RAPID, the model transports from the observational method and the model truth (based on the actual model velocities) agree well in their mean and variability. There are substantial differences among the transport estimates obtained with various methods at the MOVE site. These differences result from relatively large and time‐varying reference velocities at depth in the model, not supporting a level‐of‐no‐motion. The methods that account for these reference velocities properly at MOVE produce transports that are in good agreement with the model truth. In contrast with the observational estimates, the model transport trends at MOVE and RAPID largely agree with each other on pentadal to multi‐decadal time scales.
Geomagnetic Field Paleointensity Spanning the Past 11 Myr From Marine Magnetic Anomalies in the Southern Hemisphere
Authors: Li Yuanjie , Liu Jiabo , Liu Qingsong 
Published: May 2021

AbstractGlobal variations in geomagnetic intensity can provide dating markers for sedimentary records, which is particularly helpful in precisely reconstructing climate changes. However, there are few continuous relative paleointensity (RPI) records derived from sediments spanning the past 11 Myr, and those that exist generally bear a high degree of uncertainty. Therefore, independent evidence from other continuous paleointensity records is needed to verify the existing information. Here, we analyzed magnetic anomaly profiles from the East Pacific Rise and the Southeast Indian Ridge and discovered correlative tiny wiggles in the stacked profiles from three different areas. A comparison with a previous magnetic study on the South Atlantic Ridge and the synthetic profile from RPI records generated for the past ∼8 Myr confirmed that the small wavelength anomalies result from global geomagnetic intensity fluctuations. The newly calibrated timescales from selected marine magnetic anomalies could provide a potential dating reference for sedimentary strata.
Improved Simulation of Midlatitude Climate in a New Channel Model Compared to Contemporary Global Climate Models
Authors: Ray Pallav , Zhou Xin , Tan Haochen , Dudhia Jimy , Moncrieff Mitchell W. 
Published: May 2021

AbstractA midlatitude channel model (MCM), zonally global but meridionally bounded, is constructed for the Northern Hemisphere (0°–360°, 26°N–60°N), based on the Weather Research and Forecasting model. The MCM simulates the midlatitude at a higher resolution than typically possible in a global climate model (GCM). On the other hand, compared to four lateral boundaries in a standard regional or limited‐area model, MCM is bounded on two meridional sides only allowing the simulated atmosphere to develop more freely. Based on a 4‐year simulation at ∼0.33° horizontal grid‐spacing, the MCM realistically captures the annual mean and seasonal cycle of the midlatitude atmosphere and the meridional heat transport by the stationary and transient eddies that dominate the winter weather. Moreover, a comparison of MCM with the ensemble mean of 20 contemporary atmospheric GCMs reveals that the MCM performs better than the GCM ensemble mean. Possible applications of this new modeling configuration are discussed.
Terrestrial Gamma‐Ray Flashes Can Be Detected With Radio Measurements of Energetic In‐Cloud Pulses During Thunderstorms
Authors: Lyu Fanchao , Cummer Steven A. , Briggs Michael , Smith David M. , Mailyan Bagrat , Lesage Stephen 
Published: May 2021

AbstractMany of the details of how terrestrial gamma‐ray flashes (TGFs) are produced, including their association with upward‐propagating in‐cloud lightning leader channels, remain poorly understood. Measurements of the low‐frequency radio emissions associated with TGF production continue to provide unique views and key insights into the electrodynamics of this process. Here we report further details on the connection between energetic in‐cloud pulses (EIPs) and TGFs. With coordinated measurements from both ground‐based radio sensors and space‐based gamma‐ray detectors on the Fermi and Reuven Ramaty High Energy Solar Spectroscopic Imager spacecraft, we find that all ten +EIPs that occurred within the searched space‐and‐time window are associated with simultaneous TGFs, including two new TGFs that were not previously identified by the gamma‐ray measurements alone. The results in this study not only solidify the tight connection between +EIPs and TGFs, but also demonstrate the practicability of detecting a subpopulation of TGFs with ground‐based radio sensors alone.
Models of Resonant Wave‐Particle Interactions
Authors: Albert J. M. , Artemyev A. V. , Li W. , Gan L. , Ma Q. 
Published: May 2021

AbstractRadiation belt electrons are strongly affected by resonant interactions with cyclotron‐resonant waves. For broad band, small amplitude waves the interactions are well described by quasi‐linear diffusion in pitch angle and energy, but coherent, large amplitude waves such as strong whistler mode chorus call for a different treatment. The standard nonlinear framework reduces the problem to that of a classical pendulum. This picture has generally been confirmed by many numerical simulations, but recent studies have uncovered additional, complex behavior, not captured by the pendulum model, for particles with low pitch angle. We show that avoiding a commonly made approximation leads to a more general but still tractable “second fundamental model” Hamiltonian, which involves not one but two regions of phase trapping. We analyze its phase portraits in detail, and perform representative test particle simulations with slowly changing parameters. We find that the trajectories encompass traditional phase bunching and phase trapping as well as additional behavior best understood using the new model.
Synergistic cycles of protease activity and inflammation via PPARγ degradation in chronic obstructive pulmonary disease
Authors: Kwak Nakwon , Lee Kyoung-Hee , Woo Jisu , Kim Jiyeon , Lee Chang-Hoon , Yoo Chul-Gyu 
Published: May 2021

AbstractInflammation, oxidative stress, and protease–antiprotease imbalance have been suggested to be a pathogenic triad in chronic obstructive pulmonary disease (COPD). However, it is not clear how proteases interact with components of inflammatory pathways. Therefore, this study aimed to evaluate the effect of neutrophil elastase (NE) on lipopolysaccharide (LPS)-induced interleukin 8 (IL-8) production and determine the molecular mechanism in human bronchial epithelial cells (HBECs). Immortalized bronchial epithelial cells and primary HBECs were used to investigate the impact of NE on LPS-induced IL-8 production. The molecular mechanism by which NE modulated LPS-induced IL-8 production was confirmed in elastase-treated C57BL/6 mice and primary HBECs obtained from COPD patients and healthy controls. The results showed that NE treatment synergistically augmented LPS-induced IL-8 production in both immortalized bronchial epithelial cells and primary HBECs. NE partially degraded peroxisome proliferator-activated receptor gamma (PPARγ), which is known to regulate IL-8 production in the nucleus. Treatment with a PPARγ agonist and overexpression of PPARγ reversed the NE-induced synergistic increase in LPS-induced IL-8 production. Moreover, PPARγ levels were lower in lung homogenates and lung epithelial cells from elastase-treated mice than in those from saline-treated mice. In accordance with the findings in mice, PPARγ levels were lower in primary HBECs from COPD patients than in those from healthy never-smokers or healthy smokers. In conclusion, a vicious cycle of mutual augmentation of protease activity and inflammation resulting from PPARγ degradation plays a role in the pathogenesis of COPD.
The costs of over-control in anorexia nervosa: evidence from fMRI and ecological momentary assessment
Authors: Pauligk Sophie , Seidel Maria , Fürtjes Sophia , King Joseph A. , Geisler Daniel , Hellerhoff Inger , Roessner Veit , Schmidt Ulrike , Goschke Thomas , Walter Henrik , Strobel Alexander , Ehrlich Stefan 
Published: May 2021

AbstractA growing body of evidence suggests that a high level of self-control may, despite its positive effects, influence cognitive processing in an unfavorable manner. However, the affective costs of self-control have only rarely been investigated. Anorexia nervosa (AN) is an eating disorder that is often characterized by excessive self-control. Here, we used fMRI to explore whether over-control in AN may have negative affective consequences. 36 predominantly adolescent female AN patients and 36 age-matched healthy controls (HC) viewed negative and neutral pictures during two separate fMRI sessions before and after 10 min of rest. We tested whether abnormally elevated neural activity during the initial presentation in a brain region broadly implicated in top-down control, the dorsolateral prefrontal cortex (dlPFC), could predict subsequent activation in limbic areas relevant to bottom-up affective processing. Using ecological momentary assessment (EMA), we also tested for associations between the aforementioned neuroimaging markers and negative affective states in the two weeks following the experiment. fMRI data revealed that higher initial activation of the dlPFC in AN predicted increased amygdala reactivity during the second fMRI session, which in turn was related to increased self-reported tension during two weeks following the scan. These data suggest that over-control in AN patients may come at a cost including negative affective states on a short (minutes) as well as a longer time scale (days). This mechanism may significantly contribute to the persistence of AN.
Characteristics of mental health implications and plasma metabolomics in patients recently recovered from COVID-19
Authors: Yang Lian , Zhou Mei , Li Lingli , Luo Ping , Fan Wenliang , Xu Juanjuan , Chen Qing , Pan Feng , Lei Ping , Zheng Chuansheng , Jin Yang 
Published: May 2021

AbstractThis study aimed to explore the associations between cerebral white matter (WM) alterations, mental health status, and metabolism in recovered COVID-19 patients. We included 28 recovered COVID-19 patients and 27 healthy controls between April 2020 and June 2020. Demographic data, the mental health scores, diffusion-tensor imaging (DTI) data, and plasma metabolomics were collected and compared between the two groups. Tract-based spatial statistics and graph theory approaches were used for DTI data analysis. Untargeted metabolomics analysis of the plasma was performed. Correlation analyses were performed between these characteristics. Recovered COVID-19 patients showed decreased fractional anisotropy, increased mean diffusivity and radial diffusivity values in widespread brain regions, and significantly lower global efficiency, longer shortest path length, and less nodal local efficiency in superior occipital gyrus (all, P < 0.05, Bonferroni corrected). Our results also demonstrated significantly different plasma metabolic profiling in recovered COVID-19 patients even at 3 months after their hospital discharge, which was mainly related to purine pathways, amino acids, lipids, and amine metabolism. Certain regions with cerebral WM alterations in the recovered patients showed significant correlations with different metabolites and the mental health scores. We observed multiple alterations in both WM integrity and plasma metabolomics that may explain the deteriorated mental health of recovered COVID-19 patients. These findings may provide potential biomarkers for the mental health evaluation for the recovered COVID-19 patients and potential targets for novel therapeutics.
YTHDC1-mediated augmentation of miR-30d in repressing pancreatic tumorigenesis via attenuation of RUNX1-induced transcriptional activation of Warburg effect
Authors: Hou Yichao , Zhang Qingwei , Pang Wenjing , Hou Lidan , Liang Yu , Han Xu , Luo Xiaoyu , Wang Ping , Zhang Xintian , Li Lei , Meng Xiangjun 
Published: May 2021

AbstractPancreatic ductal adenocarcinoma (PDAC) is one of the most lethal human cancers. It thrives in a malnourished environment; however, little is known about the mechanisms by which PDAC cells actively promote aerobic glycolysis to maintain their metabolic needs. Gene Expression Omnibus (GEO) was used to identify differentially expressed miRNAs. The expression pattern of miR-30d in normal and PDAC tissues was studied by in situ hybridization. The role of miR-30d/RUNX1 in vitro and in vivo was evaluated by CCK8 assay and clonogenic formation as well as transwell experiment, subcutaneous xenograft model and liver metastasis model, respectively. Glucose uptake, ATP and lactate production were tested to study the regulatory effect of miR-30d/RUNX1 on aerobic glycolysis in PDAC cells. Quantitative real-time PCR, western blot, Chip assay, promoter luciferase activity, RIP, MeRIP, and RNA stability assay were used to explore the molecular mechanism of YTHDC1/miR-30d/RUNX1 in PDAC. Here, we discover that miR-30d expression was remarkably decreased in PDAC tissues and associated with good prognosis, contributed to the suppression of tumor growth and metastasis, and attenuation of Warburg effect. Mechanistically, the m6A reader YTHDC1 facilitated the biogenesis of mature miR-30d via m6A-mediated regulation of mRNA stability. Then, miR-30d inhibited aerobic glycolysis through regulating SLC2A1 and HK1 expression by directly targeting the transcription factor RUNX1, which bound to the promoters of the SLC2A1 and HK1 genes. Moreover, miR-30d was clinically inversely correlated with RUNX1, SLC2A1 and HK1, which function as adverse prognosis factors for overall survival in PDAC tissues. Overall, we demonstrated that miR-30d is a functional and clinical tumor-suppressive gene in PDAC. Our findings further uncover that miR-30d is a novel target for YTHDC1 through m6A modification, and miR-30d represses pancreatic tumorigenesis via suppressing aerobic glycolysis.
Wnt/ß-catenin-mediated p53 suppression is indispensable for osteogenesis of mesenchymal progenitor cells
Authors: Zhou Xin , Beilter Allyson , Xu Zhaohui , Gao Ruli , Xiong Shunbin , Paulucci-Holthauzen Adriana , Lozano Guillermina , de Crombrugghe Benoit , Gorlick Richard 
Published: May 2021

AbstractThe developmental origins of mesenchymal progenitor cells (MPCs) and molecular machineries regulating their fate and differentiation are far from defined owing to their complexity. Osteoblasts and adipocytes are descended from common MPCs. Their fates are collectively determined by an orchestra of pathways in response to physiological and external cues. The canonical Wnt pathway signals MPCs to commit to osteogenic differentiation at the expense of adipogenic fate. In contrast to ß-catenin, p53’s anti-osteogenic function is much less understood. Both activities are thought to be achieved through targetingRunx2and/or Osterix (Osx, Sp7) transcription. Precisely, how Osx activity is dictated by ß-catenin or p53 is not clarified and represents a knowledge gap that, until now, has largely been taken for granted. Using conditional lineage-tracing mice, we demonstrated that chondrocytes gave rise to a sizable fraction of MPCs, which served as progenitors of chondrocyte-derived osteoblasts (Chon-ob). Wnt/ß-catenin activity was only required at the stage of chondrocyte-derived mesenchymal progenitor (C-MPC) to Chon-ob differentiation. ß-catenin–C-MPCs lost osteogenic ability and favored adipogenesis. Mechanistically, we discovered that p53 activity was elevated in ß-catenin–MPCs including ß-catenin–C-MPCs and deleting p53 from the ß-catenin–MPCs fully restored osteogenesis. While high levels of p53 were present in the nuclei of ß-catenin–MPCs, Osx was confined to the cytoplasm, implying a mechanism that did not involve direct p53-Osx interaction. Furthermore, we found that p53’s anti-osteogenic activity was dependent on its DNA-binding ability. Our findings identify chondrocytes as an additional source for MPCs and indicate that Wnt/ß-catenin discretely regulates chondrocyte to C-MPC and the subsequent C-MPC to osteoblast developments. Most of all we unveil a previously unrecognized functional link between ß-catenin and p53, placing p53’s negative role in the context of Wnt/ß-catenin signaling-induced MPC osteogenic differentiation.
SPOP–PTEN–SUFU axis promotes progression of clear cell renal cell carcinoma via activating SHH and WNT pathway
Authors: Han Bo’ang , Sun Zhen , Yu Tingting , Wang Yu , Kuang Lun , Li Tianyuan , Cai Jing , Cao Qing , Xu Yuan , Gao Binbin , Cheng Steven Y. , Yue Shen , Liu Chen 
Published: May 2021

AbstractAlthough E3 ligase Speckle type BTB/POZ protein (SPOP) promotes tumorigenesis by acting as a key regulatory hub in clear cell renal cell carcinoma (ccRCC), the detailed molecular mechanism remains unclear. Here, we demonstrate that a well-known tumor suppressor, Suppressor of Fused (SUFU), is downregulated by SPOP. Interestingly, this downregulation depends on cullin-3(Cul3)-SPOP E3 ligase, but SUFU is not a direct substrate of SPOP. Phosphatase and tensin homolog (PTEN), a ubiquitinated substrate of SPOP, is involved in SPOP-mediated SUFU reduction. Importantly, inhibition of SUFU leads to elevated SHH and WNT signaling, consequently rescuing the reduced proliferation, migration, and invasion abilities of ccRCC cells caused by SPOP-knockdown. Moreover, combinatorial treatment with SHH and WNT inhibitors shows more effective for suppressing ccRCC cell proliferation and aggressiveness. These findings demonstrate that a novel SPOP–PTEN–SUFU axis promotes ccRCC carcinogenesis by activating SHH and WNT pathway, providing a new treatment strategy for ccRCC.
Strong spin-orbit coupling inducing Autler-Townes effect in lead halide perovskite nanocrystals
Authors: Yumoto Go , Hirori Hideki , Sekiguchi Fumiya , Sato Ryota , Saruyama Masaki , Teranishi Toshiharu , Kanemitsu Yoshihiko 
Published: May 2021

AbstractManipulation of excitons via coherent light-matter interaction is a promising approach for quantum state engineering and ultrafast optical modulation. Various excitation pathways in the excitonic multilevel systems provide controllability more efficient than that in the two-level system. However, these control schemes have been restricted to limited control-light wavelengths and cryogenic temperatures. Here, we report that lead halide perovskites can lift these restrictions owing to their multiband structure induced by strong spin-orbit coupling. Using CsPbBr3 perovskite nanocrystals, we observe an anomalous enhancement of the exciton energy shift at room temperature with increasing control-light wavelength from the visible to near-infrared region. The enhancement occurs because the interconduction band transitions between spin-orbit split states have large dipole moments and induce a crossover from the two-level optical Stark effect to the three-level Autler-Townes effect. Our finding establishes a basis for efficient coherent optical manipulation of excitons utilizing energy states with large spin-orbit splitting.
Analogical discovery of disordered perovskite oxides by crystal structure information hidden in unsupervised material fingerprints
Authors: Ihalage Achintha , Hao Yang 
Published: May 2021

AbstractCompositional disorder induces myriad captivating phenomena in perovskites. Target-driven discovery of perovskite solid solutions has been a great challenge due to the analytical complexity introduced by disorder. Here, we demonstrate that an unsupervised deep learning strategy can find fingerprints of disordered materials that embed perovskite formability and underlying crystal structure information by learning only from the chemical composition, manifested in $$({{\rm{A}}}_{1-{\rm{x}}}{{\rm{A}}^{\prime} }_{{\rm{x}}}){{\rm{BO}}}_{3}$$

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formulae. This phenomenon can be capitalized to predict the crystal symmetry of experimental compositions, outperforming several supervised machine learning (ML) algorithms. The educated nature of material fingerprints has led to the conception of analogical materials discovery that facilitates inverse exploration of promising perovskites based on similarity investigation with known materials. The search space of unstudied perovskites is screened from ~600,000 feasible compounds using experimental data powered ML models and automated web mining tools at a 94% success rate. This concept further provides insights on possible phase transitions and computational modelling of complex compositions. The proposed quantitative analysis of materials analogies is expected to bridge the gap between the existing materials literature and the undiscovered terrain.
A deep convolutional neural network for real-time full profile analysis of big powder diffraction data
Authors: Dong Hongyang , Butler Keith T. , Matras Dorota , Price Stephen W. T. , Odarchenko Yaroslav , Khatry Rahul , Thompson Andrew , Middelkoop Vesna , Jacques Simon D. M. , Beale Andrew M. , Vamvakeros Antonis 
Published: May 2021

AbstractWe present Parameter Quantification Network (PQ-Net), a regression deep convolutional neural network providing quantitative analysis of powder X-ray diffraction patterns from multi-phase systems. The network is tested against simulated and experimental datasets of increasing complexity with the last one being an X-ray diffraction computed tomography dataset of a multi-phase Ni-Pd/CeO2-ZrO2/Al2O3 catalytic material system consisting of ca. 20,000 diffraction patterns. It is shown that the network predicts accurate scale factor, lattice parameter and crystallite size maps for all phases, which are comparable to those obtained through full profile analysis using the Rietveld method, also providing a reliable uncertainty measure on the results. The main advantage of PQ-Net is its ability to yield these results orders of magnitude faster showing its potential as a tool for real-time diffraction data analysis during in situ/operando experiments.
Environment-assisted bosonic quantum communications
Authors: Pirandola Stefano , Ottaviani Carlo , Jacobsen Christian S. , Spedalieri Gaetana , Braunstein Samuel L. , Gehring Tobias , Andersen Ulrik L. 
Published: May 2021

AbstractWe consider a quantum relay that is used by two parties to perform several continuous-variable protocols of quantum communication, from entanglement distribution (swapping and distillation) to quantum teleportation, and quantum key distribution. The theory of these protocols is suitably extended to a non-Markovian model of decoherence characterized by correlated Gaussian noise in the bosonic environment. In the worst-case scenario where bipartite entanglement is completely lost at the relay, we show that the various protocols can be reactivated by the assistance of classical (separable) correlations in the environment. In fact, above a critical amount, these correlations are able to guarantee the distribution of a weaker form of entanglement (quadripartite), which can be localized by the relay into a stronger form (bipartite) that is exploitable by the parties. Our findings are confirmed by a proof-of-principle experiment where we show, for the first time, that memory effects in the environment can drastically enhance the performance of a quantum relay, well beyond the single-repeater bound for quantum and private communications.