bluuebunny/crossref_metadata_2025_split huggingface dataset:
A comparative study of an Yb-doped fiber gain-managed nonlinear amplifier seeded by femtosecond fiber lasers
Authors: Tomaszewska-Rolla Dorota , Lindberg Robert , Pasiskevicius Valdas , Laurell Fredrik , Soboń Grzegorz 
Published: January 2022

AbstractIn this work, we show that the nonlinear evolution of femtosecond seed pulses with different parameters (temporal and spectral shapes, repetition rate, pulse energy) in an Yb-fiber amplifier leads to gain-managed nonlinear amplification, enabling robust generation of high-peak-power and nearly transform-limited pulses after external compression. We demonstrate a compressed pulse duration of 33 fs with an energy of 80.5 nJ and a peak power of 2.29 MW for a source with a repetition rate of 30 MHz. For a second seed source with a repetition rate of 125 MHz, we obtained a pulse duration of 51 fs with an energy of 22.8 nJ and a peak power of 420 kW. Numerical simulations incorporating rate equations and nonlinear propagation in the amplifier provide evolutions that agree well with the experimental results. The discrepancies in the amplifier’s absorption edge appearing at low repetition rates and higher pump powers are attributed to the temperature dependence of the amplifier’s gain cross-sections. Here, we experimentally verify this attribution and thus underline the importance of accounting for the fiber core temperature for precise modelling of the short-wavelength spectral edge of the output pulses in nonlinear Yb-fiber amplifiers. We also measure, for the first time, the relative intensity noise of an amplifier operating in the gain-managed nonlinear regime. The measurements reveal a significant contribution of the amplification process to the overall output noise of the system.
Evolutionary game analysis of environmental pollution control under the government regulation
Authors: Zhou Kui , Wang Qi , Tang Junnan 
Published: January 2022

AbstractThis paper studied a tripartite evolutionary game of stakeholders in environmental pollution control. Most previous studies on this issue are limited to a focus on system dynamics with two-party game problems and lack a spatial analysis of strategy evolution. The parameters adopted are too few, and the influencing factors considered are too simple. The purpose of the paper is to introduce more parameters to study, which will have an important impact on the strategy choices of participants and the evolution path of the strategy over time. We construct a tripartite evolutionary game model of sewage enterprises, governments and the public. We establish a payment matrix and replicator equations as our method, and we also implement parameter simulations in MATLAB. In summary, we found that the reward and punishment mechanism plays an important role in environmental pollution control. Specifically: intensifying rewards and penalties will help encourage sewage enterprises to meet the discharge standard and the public to participate in pollution control action. However, increased rewards will reduce government's willingness to adopt incentive strategies; Government's reward for public's participation in the action must be greater than the increased cost of participation; Reducing the cost of sewage enterprise can also encourage them to implement standard emissions. The research presented in this paper further improves standard emissions and designs reasonable reward and punishment mechanism.
Nationwide cross-sectional survey of patients with relapsing polychondritis in 2019 demonstrates reduction of airway involvement compared with that in 2009
Authors: Shimizu Jun , Yamano Yoshihisa , Kawahata Kimito , Suzuki Noboru 
Published: January 2022

AbstractWe conducted retrospective cohort studies of patients with relapsing polychondritis (RP) twice in 2009 and 2019, using a physician questionnaire. We compared the patients’ clinical statuses between the years. Age and gender were comparable between the two surveys. Mean disease duration was longer in 2019 survey (8.3 years) than that in 2009 survey (4.8 years, P < 0.001). The mortality rate declined in 2019 survey compared with those in 2009 survey (from 9.2 to 1.6%, P < 0.001). Incidence of airway involvement decreased in 2019 survey compared with that in 2009 survey (from 49 to 37%, P = 0.012). In 2019 survey, we found more frequent use of biological agents and immunosuppressants in patients with airway involvement. When we focused on RP patients with airway involvement, physicians in 2019 chose methotrexate and calcineurin inhibitors preferentially, compared with azathioprine and cyclophosphamide. Of note is that increased use of infliximab was observed in RP patients with airway involvement, but not in those without. Reduction of airway involvement and mortality in patients with RP was observed in 2019 survey. The reduction may associate with the frequent use of biologics including infliximab in RP patients with airway involvement.
Large hemispheric differences in the Hadley cell strength variability due to ocean coupling
Authors: Chemke Rei 
Published: January 2022

AbstractBy modulating the distribution of heat, precipitation and moisture, the Hadley cell holds large climate impacts at low and subtropical latitudes. Here we show that the interannual variability of the annual mean Hadley cell strength is ~ 30% less in the Northern Hemisphere than in the Southern Hemisphere. Using a hierarchy of ocean coupling experiments, we find that the smaller variability in the Northern Hemisphere stems from dynamic ocean coupling, which has opposite effects on the variability of the Hadley cell in the Southern and Northern Hemispheres; it acts to increase the variability in the Southern Hemisphere, which is inversely linked to equatorial upwelling, and reduce the variability in the Northern Hemisphere, which shows a direct relation with the subtropical wind-driven overturning circulation. The important role of ocean coupling in modulating the tropical circulation suggests that further investigation should be carried out to better understand the climate impacts of ocean-atmosphere coupling at low latitudes.
The language of crisis: spatiotemporal effects of COVID-19 pandemic dynamics on health crisis communications by political leaders
Authors: Mandl Benjamin J. , Reis Ben Y. 
Published: January 2022

AbstractIn times of crisis, communication by leaders is essential for mobilizing an effective public response. During the COVID-19 pandemic, compliance with public health guidelines has been critical for the prevention of infections and deaths. We assembled a corpus of over 1500 pandemic-related speeches, containing over 4 million words, delivered by all 50 US state governors during the initial months of the COVID-19 pandemic. We analyzed the semantic, grammatical and linguistic-complexity properties of these speeches, and examined their relationships to COVID-19 case rates over space and time. We found that as COVID-19 cases rose, governors used stricter language to issue guidance, employed greater negation to defend their actions and highlight prevailing uncertainty, and used more extreme descriptive adjectives. As cases surged to their highest levels, governors used shorter words with fewer syllables. Investigating and understanding such characteristic responses to stress is important for improving effective public communication during major health crises.
Improved clearing method contributes to deep imaging of plant organs
Authors: Sakamoto Yuki , Ishimoto Anna , Sakai Yuuki , Sato Moeko , Nishihama Ryuichi , Abe Konami , Sano Yoshitake , Furuichi Teiichi , Tsuji Hiroyuki , Kohchi Takayuki , Matsunaga Sachihiro 
Published: January 2022

AbstractTissue clearing methods are increasingly essential for the microscopic observation of internal tissues of thick biological organs. We previously developed TOMEI, a clearing method for plant tissues; however, it could not entirely remove chlorophylls nor reduce the fluorescent signal of fluorescent proteins. Here, we developed an improved TOMEI method (iTOMEI) to overcome these limitations. First, a caprylyl sulfobetaine was determined to efficiently remove chlorophylls from Arabidopsis thaliana seedlings without GFP quenching. Next, a weak alkaline solution restored GFP fluorescence, which was mainly lost during fixation, and an iohexol solution with a high refractive index increased sample transparency. These procedures were integrated to form iTOMEI. iTOMEI enables the detection of much brighter fluorescence than previous methods in tissues of A. thaliana, Oryza sativa, and Marchantia polymorpha. Moreover, a mouse brain was also efficiently cleared by the iTOMEI-Brain method within 48 h, and strong fluorescent signals were detected in the cleared brain.
Disrupted stepwise functional brain organization in overweight individuals
Authors: Lee Hyebin , Kwon Junmo , Lee Jong-eun , Park Bo-yong , Park Hyunjin 
Published: January 2022

AbstractFunctional hierarchy establishes core axes of the brain, and overweight individuals show alterations in the networks anchored on these axes, particularly in those involved in sensory and cognitive control systems. However, quantitative assessments of hierarchical brain organization in overweight individuals are lacking. Capitalizing stepwise functional connectivity analysis, we assess altered functional connectivity in overweight individuals relative to healthy weight controls along the brain hierarchy. Seeding from the brain regions associated with obesity phenotypes, we conduct stepwise connectivity analysis at different step distances and compare functional degrees between the groups. We find strong functional connectivity in the somatomotor and prefrontal cortices in both groups, and both converge to transmodal systems, including frontoparietal and default-mode networks, as the number of steps increased. Conversely, compared with the healthy weight group, overweight individuals show a marked decrease in functional degree in somatosensory and attention networks across the steps, whereas visual and limbic networks show an increasing trend. Associating functional degree with eating behaviors, we observe negative associations between functional degrees in sensory networks and hunger and disinhibition-related behaviors. Our findings suggest that overweight individuals show disrupted functional network organization along the hierarchical axis of the brain and these results provide insights for behavioral associations.
Structure of putative tumor suppressor ALDH1L1
Authors: Tsybovsky Yaroslav , Sereda Valentin , Golczak Marcin , Krupenko Natalia I. , Krupenko Sergey A. 
Published: January 2022

AbstractPutative tumor suppressor ALDH1L1, the product of natural fusion of three unrelated genes, regulates folate metabolism by catalyzing NADP+-dependent conversion of 10-formyltetrahydrofolate to tetrahydrofolate and CO2. Cryo-EM structures of tetrameric rat ALDH1L1 revealed the architecture and functional domain interactions of this complex enzyme. Highly mobile N-terminal domains, which remove formyl from 10-formyltetrahydrofolate, undergo multiple transient inter-domain interactions. The C-terminal aldehyde dehydrogenase domains, which convert formyl to CO2, form unusually large interfaces with the intermediate domains, homologs of acyl/peptidyl carrier proteins (A/PCPs), which transfer the formyl group between the catalytic domains. The 4′-phosphopantetheine arm of the intermediate domain is fully extended and reaches deep into the catalytic pocket of the C-terminal domain. Remarkably, the tetrameric state of ALDH1L1 is indispensable for catalysis because the intermediate domain transfers formyl between the catalytic domains of different protomers. These findings emphasize the versatility of A/PCPs in complex, highly dynamic enzymatic systems.
Real time imaging of single extracellular vesicle pH regulation in a microfluidic cross-flow filtration platform
Authors: Riazanski Vladimir , Mauleon Gerardo , Lucas Kilean , Walker Samuel , Zimnicka Adriana M. , McGrath James L. , Nelson Deborah J. 
Published: January 2022

AbstractExtracellular vesicles (EVs) are cell-derived membranous structures carrying transmembrane proteins and luminal cargo. Their complex cargo requires pH stability in EVs while traversing diverse body fluids. We used a filtration-based platform to capture and stabilize EVs based on their size and studied their pH regulation at the single EV level. Dead-end filtration facilitated EV capture in the pores of an ultrathin (100 nm thick) and nanoporous silicon nitride (NPN) membrane within a custom microfluidic device. Immobilized EVs were rapidly exposed to test solution changes driven across the backside of the membrane using tangential flow without exposing the EVs to fluid shear forces. The epithelial sodium-hydrogen exchanger, NHE1, is a ubiquitous plasma membrane protein tasked with the maintenance of cytoplasmic pH at neutrality. We show that NHE1 identified on the membrane of EVs is functional in the maintenance of pH neutrality within single vesicles. This is the first mechanistic description of EV function on the single vesicle level.
[13C]bicarbonate labelled from hyperpolarized [1-13C]pyruvate is an in vivo marker of hepatic gluconeogenesis in fasted state
Authors: Can Emine , Bastiaansen Jessica A. M. , Couturier Dominique-Laurent , Gruetter Rolf , Yoshihara Hikari A. I. , Comment Arnaud 
Published: January 2022

AbstractHyperpolarized [1-13C]pyruvate enables direct in vivo assessment of real-time liver enzymatic activities by 13C magnetic resonance. However, the technique usually requires the injection of a highly supraphysiological dose of pyruvate. We herein demonstrate that liver metabolism can be measured in vivo with hyperpolarized [1-13C]pyruvate administered at two- to three-fold the basal plasma concentration. The flux through pyruvate dehydrogenase, assessed by 13C-labeling of bicarbonate in the fed condition, was found to be saturated or partially inhibited by supraphysiological doses of hyperpolarized [1-13C]pyruvate. The [13C]bicarbonate signal detected in the liver of fasted rats nearly vanished after treatment with a phosphoenolpyruvate carboxykinase (PEPCK) inhibitor, indicating that the signal originates from the flux through PEPCK. In addition, the normalized [13C]bicarbonate signal in fasted untreated animals is dose independent across a 10-fold range, highlighting that PEPCK and pyruvate carboxylase are not saturated and that hepatic gluconeogenesis can be directly probed in vivo with hyperpolarized [1-13C]pyruvate.
Prediction of heptagonal bipyramidal nonacoordination in highly viable [OB-M©B7O7-BO]− (M = Fe, Ru, Os) complexes
Authors: Jin Bo , Li Hai-Ru , Wei Zhihong , Yan Miao , Yuan Caixia , Wu Yan-Bo , Li Si-Dian 
Published: January 2022

AbstractNon-spherical distributions of ligand atoms in coordination complexes are generally unfavorable due to higher repulsion than for spherical distributions. To the best of our knowledge, non-spherical heptagonal bipyramidal nonacoordination is hitherto unreported, because of extremely high repulsion among seven equatorial ligand atoms. Herein, we report the computational prediction of such nonacoordination, which is constructed by the synergetic coordination of an equatorial hepta-dentate centripetal ligand (B7O7) and two axial mono-dentate ligands (-BO) in the gear-like mono-anionic complexes [OB-M©B7O7-BO]– (M = Fe, Ru, Os). The high repulsion among seven equatorial ligand B atoms has been compensated by the strong B–O bonding. These complexes are the dynamically stable (up to 1500 K) global energy minima with the HOMO-LUMO gaps of 7.15 to 7.42 eV and first vertical detachment energies of 6.14 to 6.66 eV (being very high for anions), suggesting their high probability for experimental realization in both gas-phase and condensed phases. The high stability stems geometrically from the surrounded outer-shell oxygen atoms and electronically from meeting the 18e rule as well as possessing the σ + π + δ triple aromaticity. Remarkably, the ligand-metal interactions are governed not by the familiar donation and backdonation interactions, but by the electrostatic interactions and electron-sharing bonding.
Phase-sensitive seeded modulation instability in passive fiber resonators
Authors: Bessin Florent , Naveau Corentin , Conforti Matteo , Kudlinski Alexandre , Szriftgiser Pascal , Mussot Arnaud 
Published: January 2022

AbstractModulation instability is one of the most ubiquitous phenomena in physics. Here we investigate the phase-sensitive properties of modulation instability with harmonic seeding in passive fiber resonators. Theoretical investigations based on the Lugiato−Lefever equation with time dependent pump and a three-wave truncation show that the dynamics of the system is sensitive to the relative phase between input signal, idler, and pump waves. The modulation instability gain can even vanish for a peculiar value of the initial relative phase. An advanced multi-heterodyne measurement technique had been developed to record the real time evolution, round-trip to round-trip, of the power and phase of the output cavity field to confirm these theoretical predictions.
Coexistence and tuning of spin-singlet and triplet transport in spin-filter Josephson junctions
Authors: Ahmad Halima Giovanna , Minutillo Martina , Capecelatro Roberto , Pal Avradeep , Caruso Roberta , Passarelli Gianluca , Blamire Mark G. , Tafuri Francesco , Lucignano Procolo , Massarotti Davide 
Published: January 2022

AbstractThe increased capabilities of coupling more and more materials through functional interfaces are paving the way to a series of exciting experiments and extremely advanced devices. Here we focus on the capability of magnetically inhomogeneous superconductor/ferromagnet (S/F) interfaces to generate spin-polarized triplet pairs. We build on previous achievements on spin-filter ferromagnetic Josephson junctions (JJs) and find direct correspondence between neat experimental benchmarks in the temperature behavior of the critical current and theoretical modelling based on microscopic calculations, which allow to determine a posteriori spin-singlet and triplet correlation functions. This kind of combined analysis provides an accurate proof of the coexistence and tunability of singlet and triplet transport. This turns to be a powerful way to model disorder and spin-mixing effects in a JJ to enlarge the space of parameters, which regulate the phenomenology of the Josephson effect and could be applied to a variety of hybrid JJs.
Magnonic superradiant phase transition
Authors: Bamba Motoaki , Li Xinwei , Marquez Peraca Nicolas , Kono Junichiro 
Published: January 2022

AbstractIn the superradiant phase transition (SRPT), coherent light and matter fields are expected to appear spontaneously in a coupled light–matter system in thermal equilibrium. However, such an equilibrium SRPT is forbidden in the case of charge-based light–matter coupling, known as no-go theorems. Here, we show that the low-temperature phase transition of ErFeO3 at a critical temperature of approximately 4 K is an equilibrium SRPT achieved through coupling between Fe3+ magnons and Er3+ spins. By verifying the efficacy of our spin model using realistic parameters evaluated via terahertz magnetospectroscopy and magnetization experiments, we demonstrate that the cooperative, ultrastrong magnon–spin coupling causes the phase transition. In contrast to prior studies on laser-driven non-equilibrium SRPTs in atomic systems, the magnonic SRPT in ErFeO3 occurs in thermal equilibrium in accordance with the originally envisioned SRPT, thereby yielding a unique ground state of a hybrid system in the ultrastrong coupling regime.
Dissipation-driven strange metal behavior
Authors: Caprara Sergio , Castro Carlo Di , Mirarchi Giovanni , Seibold Götz , Grilli Marco 
Published: January 2022

AbstractAnomalous metallic properties are often observed in the proximity of quantum critical points, with violation of the Fermi Liquid paradigm. We propose a scenario where, near the quantum critical point, dynamical fluctuations of the order parameter with finite correlation length mediate a nearly isotropic scattering among the quasiparticles over the entire Fermi surface. This scattering produces a strange metallic behavior, which is extended to the lowest temperatures by an increase of the damping of the fluctuations. We phenomenologically identify one single parameter ruling this increasing damping when the temperature decreases, accounting for both the linear-in-temperature resistivity and the seemingly divergent specific heat observed, e.g., in high-temperature superconducting cuprates and some heavy-fermion metals.
Asynchronous responses of aquatic ecosystems to hydroclimatic forcing on the Tibetan Plateau
Authors: Aichner Bernhard , Wünnemann Bernd , Callegaro Alice , van der Meer Marcel T. J. , Yan Dada , Zhang Yongzhan , Barbante Carlo , Sachse Dirk 
Published: January 2022

AbstractHigh-altitude ecosystems react sensitively to hydroclimatic triggers. Here we evaluated the ecological and hydrological changes in a glacier-influenced lake (Hala Hu, China) since the last glacial. Rapid fluctuations of aquatic biomarker concentrations, ratios, and hydrogen isotope values, from 15 to 14,000 and 8 to 5000 years before present, provided evidence for aquatic regime shifts and changes in lake hydrology. In contrast, most negative hydrogen isotope values of terrestrial biomarkers were observed between 9 and 7,000 years before present. This shows that shifts of vapour sources and increased precipitation amounts were not relevant drivers behind ecosystem changes in the studied lake. Instead, receding glaciers and increased meltwater discharge, driven by higher temperatures, caused the pronounced ecological responses. The shifts within phytoplankton communities in the Late Glacial and mid Holocene illustrate the vulnerability of comparable ecosystems to climatic and hydrological changes. This is relevant to assess future ecological responses to global warming.
[12]aneN3-Conjugated AIEgens with two-photon imaging properties for synergistic gene/photodynamic therapy in vitro and in vivo
Authors: Liu Xu-Ying , Yang Jing-Bo , Wu Cheng-Yan , Tang Quan , Lu Zhong-Lin , Lin Lan 
Published: January 2022

Six amphiphiles consisting of macrocyclic polyamine triazole-[12]aneN3 (M) and tetraphenylethenethiophene modified cyanoacrylate (TTC) moiety linked with alkyl chains (L), have been synthesized for synergetic anticancer gene therapy and photodynamic therapy.
An attention‐based cascade R‐CNN model for sternum fracture detection in X‐ray images
Authors: Jia Yang , Wang Haijuan , Chen Weiguang , Wang Yagang , Yang Bin 
Published: January 2022

AbstractFracture is one of the most common and unexpected traumas. If not treated in time, it may cause serious consequences such as joint stiffness, traumatic arthritis, and nerve injury. Using computer vision technology to detect fractures can reduce the workload and misdiagnosis of fractures and also improve the fracture detection speed. However, there are still some problems in sternum fracture detection, such as the low detection rate of small and occult fractures. In this work, the authors have constructed a dataset with 1227 labelled X‐ray images for sternum fracture detection. The authors designed a fully automatic fracture detection model based on a deep convolution neural network (CNN). The authors used cascade R‐CNN, attention mechanism, and atrous convolution to optimise the detection of small fractures in a large X‐ray image with big local variations. The authors compared the detection results of YOLOv5 model, cascade R‐CNN and other state‐of‐the‐art models. The authors found that the convolution neural network based on cascade and attention mechanism models has a better detection effect and arrives at an mAP of 0.71, which is much better than using the YOLOv5 model (mAP = 0.44) and cascade R‐CNN (mAP = 0.55).