bluuebunny/crossref_metadata_2025_split huggingface dataset:
Extending Ozone‐Precursor Relationships in China From Peak Concentration to Peak Time
Authors: Qu Hang , Wang Yuhang , Zhang Ruixiong , Li Jianfeng 
Published: October 2020

AbstractHigh ozone concentrations have become the major summertime air quality problem in China. Extensive in situ observations are deployed for developing strategies to effectively control the emissions of ozone precursors, that is, nitrogen oxides (NOX = NO + NO2) and volatile organic compounds (VOCs). The modeling analysis of in situ observations often makes uses of the dependence of ozone peak concentration on NOX and VOC emissions, because ozone observations are among the most widely available air quality measurements. To extract more information from regulatory ozone observations, we extend the ozone‐precursor relationship to ozone peak time in this study. We find that the sensitivities of ozone peak time and concentration are complementary for regions with large anthropogenic emissions such as China. The ozone peak time is sensitive to both VOC and NOX emissions, and the sensitivity is nearly linear in the transition regime of ozone production compared to the changing ozone peak concentration sensitivity in this regime, making the diagnostics of ozone peak time particularly valuable. The extended ozone‐precursor relationships can be readily applied to understand the effects on ozone by emission changes of NOX and VOC and to assess potential biases of NOX and VOC emission inventories. These observation constraints based on regulatory ozone observations can complement the other measurement and modeling analysis methods nicely. Furthermore, we suggest that the ozone peak time sensitivity we discussed here to be used as a model evaluation measure before the empirical kinetic modeling approach (EKMA) diagram is applied to understand the effectiveness of emission control on ozone concentrations.
Uncertainty Quantification of Ocean Parameterizations: Application to the K‐Profile‐Parameterization for Penetrative Convection
Authors: Souza A. N. , Wagner G. L. , Ramadhan A. , Allen B. , Churavy V. , Schloss J. , Campin J. , Hill C. , Edelman A. , Marshall J. , Flierl G. , Ferrari R. 
Published: October 2020

AbstractParameterizations of unresolved turbulent processes often compromise the fidelity of large‐scale ocean models. In this work, we argue for a Bayesian approach to the refinement and evaluation of turbulence parameterizations. Using an ensemble of large eddy simulations of turbulent penetrative convection in the surface boundary layer, we demonstrate the method by estimating the uncertainty of parameters in the convective limit of the popular “K‐Profile Parameterization.” We uncover structural deficiencies and propose an alternative scaling that overcomes them.
Description and Climate Simulation Performance of CAS‐ESM Version 2
Authors: Zhang He , Zhang Minghua , Jin Jiangbo , Fei Kece , Ji Duoying , Wu Chenglai , Zhu Jiawen , He Juanxiong , Chai Zhaoyang , Xie Jinbo , Dong Xiao , Zhang Dongling , Bi Xunqiang , Cao Hang , Chen Huansheng , Chen Kangjun , Chen Xueshun , Gao Xin , Hao Huiqun , Jiang Jinrong , Kong Xianghui , Li Shigang , Li Yangchun , Lin Pengfei , Lin Zhaohui , Liu Hailong , Liu Xiaohong , Shi Ying , Song Mirong , Wang Huijun , Wang Tianyi , Wang Xiaocong , Wang Zifa , Wei Ying , Wu Baodong , Xie Zhenghui , Xu Yongfu , Yu Yongqiang , Yuan Liang , Zeng Qingcun , Zeng Xiaodong , Zhao Shuwen , Zhou Guangqing , Zhu Jiang 
Published: October 2020

AbstractThe second version of Chinese Academy of Sciences Earth System Model (CAS‐ESM 2) is described with emphasis on the development process, strength and weakness, and climate sensitivities in simulations of the Coupled Model Intercomparison Project (CMIP6) DECK experiments. CAS‐ESM 2 was built as a numerical model to simulate both the physical climate system as well as atmospheric chemistry and carbon cycle. It is a newcomer in the international modeling community to provide sufficiently independent solutions of climate simulations from those of other models. Performances of the model in simulating the basic states of the radiation budget of the atmosphere and ocean, precipitation, circulations, variabilities, and the twentieth century warming are presented. Model biases and their possible causes are discussed. Strength includes horizontal heat transport in the atmosphere and oceans, vertical profile of the Atlantic Meridional Overturning Circulation; weakness includes the double intertropical convergence zone (ITCZ) and stronger amplitude of the El Niño–Southern Oscillation (ENSO) that are also common in many other models. The simulated the twentieth century warming shares a similar discrepancy with observations as in several other models—less warming in the 1920s and stronger cooling in the 1960s than in observation—at the time when there was a steep increase of anthropogenic aerosols. As a result, the twentieth century warming is about 60% of the observed warming despite that the model simulated a similar slope of warming trend after 1980 to observation. The model has an equilibrium climate sensitivity of 3.4 K with a positive cloud feedback from the shortwave radiation.
Disproving the Presence of Paleozoic‐Triassic Metamorphic Rocks on the Island of Zannone (Central Italy): Implications for the Early Stages of the Tyrrhenian‐Apennines Tectonic Evolution
Authors: Curzi Manuel , Billi Andrea , Carminati Eugenio , Rossetti Federico , Albert Richard , Aldega Luca , Cardello Giovanni Luca , Conti Alessia , Gerdes Axel , Smeraglia Luca , Van der Lelij Roelant , Vignaroli Gianluca , Viola Giulio 
Published: October 2020

AbstractThe inner Apennines (Italy) are characterized by scattered outcrops of continent‐derived orogenic metamorphic units exposed along the Tyrrhenian coast from northern to southern Apennines. At least since the 1970s, some peculiar rocks exposed on Zannone Island (central Italy) have been described as the only Paleozoic‐Triassic metamorphic complex linking those exposed in the northern—with those in the southern Apennines. Assessing the protolith nature, thermobaric conditions, and structural features of what is accepted to be the metamorphic unit of Zannone is, therefore, crucial to elucidate the early paleotectonic evolution of the Apennines‐Tyrrhenian orogenic system. To that end, we interpreted seismic reflection profiles offshore Zannone, we carried out mesoscale and microscale structural investigations of representative outcrops on the island, performed X‐ray diffraction analysis, and K‐Ar and U‐Pb geochronology of representative clay gouge and syntectonic carbonate veins. Results show that the metamorphic rocks of Zannone can actually be reinterpreted as belonging to nonmetamorphic siliciclastic turbidites, likely deposited in foredeep settings, and coeval to the Oligocene‐Miocene Macigno Fm. of the northern Apennines. The turbiditic sequence was overthrust by Triassic dolostone in the early Miocene (~22 Ma), weakly deformed at <200°C, and downfaulted by postorogenic extensional faults starting ~7 Ma ago. Hence, Zannone represents a unique geological location in central Italy where to study the innermost (i.e. oldest) thrust sheet of the central‐northern Apennines, thereby shedding new light onto the early tectonics of the Apennines. Based on this evidence, a new evolutionary scheme for the early stage of the Apennines tectonic evolution is proposed.
Seismicity in a Transpressional Volcanic Arc: The Liquiñe‐Ofqui Fault System in the Puyuhuapi Area, Southern Andes, Chile (44°S)
Authors: Pérez‐Estay Nicolás , Yáñez Gonzalo , Crempien Jorge , Roquer Tomás , Cembrano José , Valdenegro Pablo , Aravena Diego , Arancibia Gloria , Morata Diego 
Published: October 2020

AbstractUnderstanding the relationship between crustal faults and volcanic activity in transpressional environments is a main goal in geosciences and could help to understand geothermal resources and evaluate geological hazards. In the Andean Southern Volcanic Zone (SVZ), Chile, recorded seismicity is scarce, and few studies have evaluated the relationship between volcanic activity and crustal faults from seismic observations. Thus, in this study, we deployed a seismic network for almost 1 year to understand the brittle deformation of the upper crust within the Puyuhuapi area, located at ~44°S in the SVZ. We analyzed the location and kinematics of seismicity together with previously published field structural geological data. Considering these results, we developed an integrative tectonic model for the area and discussed which faults facilitate magma transport through the crust. Our results indicate the existence of two NNE‐oriented seismogenic dextral to dextral‐reverse regional faults that generate a duplex in a continental‐scale fault setting. Inside the duplex, we observed normal to strike‐slip normal focal mechanisms which recurrently have NE trending nodal planes. At a regional scale, a strike‐slip tectonic environment has a N60°E/18° shortening direction and a N151°E/03° extension direction. We conclude that stratovolcanoes are located inside the duplex in a local transtensional environment where NE oriented normal faulting may occur. These faults facilitate magma transport since they represent the preferential orientation for dilatational fractures. Conversely, in local transpressional environments such as the Puyuhuapi fault (NNE oriented dextral to dextral‐reverse kinematics), only minor eruptive centers of small volume are emplaced, suggesting a less productive magma transportation process.
Metabolic defects in splenic B cell compartments from patients with liver cirrhosis
Authors: Huang Man , Liu Xiaoju , Ye Haocheng , Zhao Xin , Zhao Juanjuan , Liu Yang , He Xiaomeng , Qu Mengmeng , Pan Jing , Hou Baidong , Cheng Yongqian , Liu Zhenwen , Li Zhiwei , Liu Lei , Sun Jian , Zhang Shuye , Zhang Zheng 
Published: October 2020

AbstractLiver cirrhosis is associated with defective vaccine responses and increased infections. Dysregulated B cell compartments in cirrhotic patients have been noticed but not well characterized, especially in the spleen. Here, we comprehensively investigated B cell perturbations from the spleens and peripheral blood of cirrhotic patients. We found that liver cirrhosis significantly depleted both switched and nonswitched splenic memory B cells, which was further confirmed histologically. Bulk RNA-seq revealed significant metabolic defects as the potential mechanism for the impaired splenic B cell functions. Functionally, the splenic memory B cells from cirrhotic patients showed strong metabolic defects and reduced proliferation compared with those from healthy controls. Thus, liver cirrhosis extensively disturbs the splenic and peripheral B cell compartments, which may contribute to defective humoral immunity during liver cirrhosis.
N6-methyladenosine METTL3 promotes cervical cancer tumorigenesis and Warburg effect through YTHDF1/HK2 modification
Authors: Wang Qianqing , Guo Xiangcui , Li Li , Gao Zhihui , Su Xiaoke , Ji Mei , Liu Juan 
Published: October 2020

AbstractN6-methyladenosine (m6A) serves as the most common and conserved internal transcriptional modification. However, the roles of m6A on cervical cancer (CC) tumorigenesis are still unclear. Here, results indicated that METTL3 was significantly upregulated in CC tissue and cells, which was closely correlated with the lymph node metastasis and poor prognosis of CC patients. MeRIP-Seq analysis revealed the m6A profiles in CC cells. Functionally, METTL3 promoted the proliferation and Warburg effect (aerobic glycolysis) of CC cells. Mechanistically, METTL3 targeted the 3’-Untranslated Region (3’-UTR) of hexokinase 2 (HK2) mRNA. Moreover, METTL3 recruited YTHDF1, a m6A reader, to enhance HK2 stability. These findings demonstrated that METTL3 enhanced the HK2 stability through YTHDF1-mediated m6A modification, thereby promoting the Warburg effect of CC, which might promote a novel insight for the CC treatment.
Hippocampal neural stem cells are more susceptible to the neurotoxin BMAA than primary neurons: effects on apoptosis, cellular differentiation, neurite outgrowth, and DNA methylation
Authors: Pierozan Paula , Cattani Daiane , Karlsson Oskar 
Published: October 2020

AbstractDevelopmental exposure to the environmental neurotoxin β-N-methylamino-l-alanine (BMAA), a proposed risk factor for neurodegenerative disease, can induce long-term cognitive impairments and neurodegeneration in rats. While rodent studies have demonstrated a low transfer of BMAA to the adult brain, this toxin is capable to cross the placental barrier and accumulate in the fetal brain. Here, we investigated the differential susceptibility of primary neuronal cells and neural stem cells from fetal rat hippocampus to BMAA toxicity. Exposure to 250 µM BMAA induced cell death in neural stem cells through caspase-independent apoptosis, while the proliferation of primary neurons was reduced only at 3 mM BMAA. At the lowest concentrations tested (50 and 100 µM), BMAA disrupted neural stem cell differentiation and impaired neurite development in neural stem cell-derived neurons (e.g., reduced neurite length, the number of processes and branches per cell). BMAA induced no alterations of the neurite outgrowth in primary neurons. This demonstrates that neural stem cells are more susceptible to BMAA exposure than primary neurons. Importantly, the changes induced by BMAA in neural stem cells were mitotically inherited to daughter cells. The persistent nature of the BMAA-induced effects may be related to epigenetic alterations that interfere with the neural stem cell programming, as BMAA exposure reduced the global DNA methylation in the cells. These findings provide mechanistic understanding of how early-life exposure to BMAA may lead to adverse long-term consequences, and potentially predispose for neurodevelopmental disorders or neurodegenerative disease later in life.
MicroRNA-488 inhibits proliferation and motility of tumor cells via downregulating FSCN1, modulated by Notch3 in breast carcinomas
Authors: Wu Yang , Yuan Ming-Heng , Wu Hua-Tao , Chen Wen-Jia , Zhang Man-Li , Ye Qian-Qian , Liu Jing , Zhang Guo-Jun 
Published: October 2020

AbstractAs important modulators in multiple physiological processes, microRNAs (miRNAs) have been reported in various malignant tumors, including breast cancer. The current study investigated the function of a new tumor suppressor microRNA, miR-488, and its molecular mechanism of metastasis in breast cancers. CCK8 and transwell assays revealed that the upregulated miR-488 level significantly inhibited the proliferation and migration of breast cancer cells. As a potential downstream gene, the mRNA and protein level of FSCN1 was suppressed by increased miR-488 and vice versa. Luciferase assay showed that miR-488 directly bind to the 3′UTR of FSCN1 and suppressed the translation process of FSCN1. The promoter region of miR-488 was directly bound by Notch3 and promoted the expression of miR-488 transcriptionally. Immunohistochemistry results revealed that in patients with breast cancer, the expression of Notch3 and were negatively correlated with the FSCN1 levels significantly. Therefore, the current finding predicted miR-488 as a tumor suppressor molecule in breast cancer, and demonstrated that Notch3/miR-488/FSCN1 axis is established and involved in regulating the metastasis of breast cancers, providing novel therapeutic targets for patients with breast cancers.
Dual‐band reconfigurable metasurface‐assisted Fabry–Pérot antenna with high‐gain radiation and low scattering
Authors: Bai Lin , Zhang Xin Ge , Wang Qiang , Huang Chen Xi , Jiang Wei Xiang , Cui Tie Jun 
Published: October 2020

The authors have proposed a dual‐band reconfigurable Fabry–Pérot (F‐P) cavity antenna with high gain and meanwhile small radar cross‐sections (RCSs) in wideband. Different from the traditional F‐P antennas, they used a dynamic metasurface reflective plane (DMRP) as the lower superstrate to realise reconfigurable functions and a digital coding metasurface as the upper superstrate to achieve wideband RCS reduction. To investigate the dual‐band reconfigurability, a wideband rectangular waveguide is used to feed the F‐P antenna. By varying the bias voltage applied to varactors embedded in the elements of DMRP, the reflection phase of DMRP is changed and the two operating frequencies can be tuned electronically. To realise RCS reduction, they adopted a meticulous arrangement of the coding elements on partially reflecting surface. The designed metasurface‐assisted F‐P antenna has good radiation performance with high gain, high aperture efficiency, and high radiation efficiency. In the experiments, a prototype was fabricated via printed circuit board technology, and measured results agree well with numerical simulations. The measured peak gain reaches 17.52 dBi and the maximum aperture efficiency is 56.97%. The two reconfigurable bandwidths cover 5.10–5.40 and 6.60–6.93 GHz, respectively; and 7 dB RCS reduction is achieved from 9.40 to 13.7 GHz for arbitrary polarisation
Design of emergency breakaway device for helicopter hovering refuelling
Authors: Yu Min‐Quan , Yang Yu‐Liang , Wang Hai‐Tao 
Published: October 2020

In the helicopter hover refuelling system, the emergency breakaway device is an important component to ensure the safety of the helicopter. It requires automatic disconnection and sealing of the pipeline under the tension of 1700–2000 N. The claw type emergency breakaway device was designed, the three‐dimensional model is established for dynamic analysis, and the optimal parameters of the breakaway device are obtained by orthogonal experiment. Then, the calculation equation of the braking force is obtained through analysis. The sealing structure of the emergency breakaway device adopts a pair of poppet valves. In order to verify the reliability of the braking force and the seal, the emergency breakaway device is subjected to a water‐passing test. The results show that the emergency breakaway device is separated with the required breaking force and the leakage amount is zero after the breakaway.
Analysis and suppression of torsional vibration in electromechanical coupling transmission system of high‐speed train
Authors: Jing‐Bo Zhao , Chao‐Yue Yang , Chao‐Yi Pu 
Published: October 2020

The high‐speed train transmission system is a complex electromechanical coupling system. In this study, the torsional vibration of a train transmission system was studied. The centralised mass model of the mechanical structure of the coupling system was established. The natural vibration characteristics of the mechanical mechanism system were analysed. The results show that the natural vibration frequency of the universal shaft was 4.08 Hz, the natural vibration frequency of the pinion was 7.24 Hz, the natural vibration frequency of the big gear was 35.6 Hz, and the natural vibration frequency of the wheelset was 107.48 Hz. The traction motor model was built, and by considering the electromechanical coupling of the system, a torsional vibration suppression strategy for harmonic components in the motor is proposed. The effectiveness of the suppression strategy was verified by MATLAB/Simulink model simulation.
Sodium–Calcium Exchanger Reverse Mode Sustains Dichotomous Ion Fluxes Required for Procoagulant COAT Platelet Formation
Authors: Aliotta Alessandro , Bertaggia Calderara Debora , Zermatten Maxime G. , Alberio Lorenzo 
Published: October 2020

AbstractProcoagulant collagen-and-thrombin (COAT)-activated platelets represent a subpopulation of activated platelets, which retain a coat of prohemostatic proteins and express phosphatidylserine on their surface. Dichotomous intracellular signaling generating procoagulant platelet activity instead of traditional aggregating endpoints is still not fully elucidated. It has been demonstrated that secondary messengers such as calcium and sodium play a critical role in platelet activation. Therefore, we developed a flow cytometric analysis to investigate intracellular ion fluxes simultaneously during generation of aggregating and procoagulant platelets. Human platelets were activated by convulxin-plus-thrombin. Cytosolic calcium, sodium, and potassium ion fluxes were visualized by specific ion probes and analyzed by flow cytometry. We observed high and prolonged intracellular calcium concentration, transient sodium increase, and fast potassium efflux in COAT platelets, whereas aggregating non-COAT platelets rapidly decreased their calcium content, maintaining higher cytosolic sodium, and experiencing lower and slower potassium depletion. Considering these antithetical patterns, we investigated the role of the sodium–calcium exchanger (NCX) during convulxin-plus-thrombin activation. NCX inhibitors, CBDMB and ORM-10103, dose-dependently reduced the global calcium mobilization induced by convulxin-plus-thrombin activation and dose-dependently prevented formation of procoagulant COAT platelets. Our data demonstrate that both NCX modes are used after convulxin-plus-thrombin-induced platelet activation. Non-COAT platelets use forward-mode NCX, thus pumping calcium out and moving sodium in, while COAT platelets rely on reverse NCX function, which pumps additional calcium into the cytosol, by extruding sodium. In conclusion, we described for the first time the critical and dichotomous role of NCX function during convulxin-plus-thrombin-induced platelet activation.
A Critical Review of Damage and Failure of Composite Wind Turbine Blade Structures
Authors: Chen Xiao , Eder Martin A. 
Published: October 2020

AbstractAdvancing beyond the historic feasibility limits deemed by designers, wind turbine rotor blades have eventually surpassed the 100m milestone, making them reside among the largest single components in the world made of fiber composite materials. In the development of wind energy, aerodynamics has been an essential field of research, just as it will still be, the recent two decades witnesses structures becoming more critical due to the ever-increasing size of the rotor blades. The fact is simple: for wind turbines to operate continuously and cost-efficiently, rotor blades must maintain their structural integrity and reliability. This study reviews recent advances in the field of the structural integrity of large scale composite wind turbine blades. A particular focus is placed on damage and failure in such structures from the triad of field observations, laboratory experiments and numerical modeling. This study also identifies the established knowledge, the latest achievements, the topical research fields and the current challenges for future research and development.
Microscale testing and modelling for damage tolerant composite materials and structures
Authors: Sørensen Bent F 
Published: October 2020

Abstract
There is a need for damage tolerant composite material for very large engineering structures such as wind turbine rotor blades. The development of improved composite materials with higher damage tolerance will be most efficiently guided by models of the relevant damage modes. Two damage modes are considered in the present paper: Fatigue damage due to in-plane tensile stresses in the fibre direction and cyclic delamination crack growth from a ply drop. For both failure modes the damage evolution is considered at macro- and microscale. Micromechanical models are used to illustrate how changes in the mechanical properties of fibre, matrix and the fibre/matrix interface can lead to an increased damage tolerance material. Also, micromechanical testing methods for characterizing the relevant micromechanical parameters are discussed.