bluuebunny/crossref_metadata_2025_split huggingface dataset:
Imprints of Tropical Cyclones on Structural Characteristics of Mesoscale Oceanic Eddies Over the Western North Pacific
Authors: Ma Zhanhong , Zhang Zheliang , Fei Jianfang , Wang Huizan 
Published: May 2021

AbstractThe imprints of tropical cyclones (TCs) on structural characteristics of mesoscale oceanic eddies over the western North Pacific are investigated. Results reveal a statistically significant role of TCs in modulating the structural characteristics of both cold‐core eddies (CCEs) and warm‐core eddies (WCEs). The eddy strength in terms of amplitude and circulation speed is intensified for CCEs while is weakened for WCEs after the passage of TCs. The size of WCEs is decreased by TCs, while the CCE is enlarged shortly and then decreased subsequently. The TC‐induced decrease in mixed‐layer depth is larger in WCEs, causing comparable mixed‐layer depths between CCEs and WCEs. The strength changes of CCEs depend highly on the intensity and translation speed of TCs. The lifetimes of both CCEs and WCEs are significantly prolonged by TC forcing. The air‐sea energy exchange is modulated by both CCEs and WCEs via changing the response of sea surface temperature.
Impacts of COVID‐19 on Black Carbon in Two Representative Regions in China: Insights Based on Online Measurement in Beijing and Tibet
Authors: Liu Yue , Wang Yinan , Cao Yang , Yang Xi , Zhang Tianle , Luan Mengxiao , Lyu Daren , Hansen Anthony D. A. , Liu Baoxian , Zheng Mei 
Published: May 2021

AbstractUnder the influence of Coronavirus Disease 2019 (COVID‐19), China conducted a nationwide lockdown (LD) which significantly reduced anthropogenic emissions. To analyze the different impacts of COVID‐19 on black carbon (BC) in the two representative regions in China, one‐year continuous online measurements of BC were conducted simultaneously in Beijing and Tibet. The average concentration in the LD period was 20% higher than that in the pre‐LD period in Beijing, which could be attributed to the increase of transport from southwestern neighboring areas and enhanced aged BC. In contrast to megacity, the average concentration of BC in Tibet decreased over 70% in the LD period, suggesting high sensitivity of plateau background areas to the anthropogenic emission reduction in South Asia. Our study clearly showed that BC responded very differently in megacity and background areas to the change of anthropogenic emission under the lockdown intervention.
Contribution of the Two Types of Ekman Pumping Induced Eddy Heat Flux to the Total Vertical Eddy Heat Flux
Authors: Li Dapeng , Chang Ping , Ramachandran Sanjiv , Jing Zhao , Zhang Qiuying , Kurian Jaison , Gopal Abishek , Yang Haiyuan 
Published: May 2021

AbstractBased on eddy‐rich (0.1° horizontal resolution for ocean) Community Earth System Model simulations, we compute the Ekman pumping induced vertical eddy heat flux using two formulations: the classical and the Stern‐Ekman pumping. The two mechanisms yield similar patterns in the eddy‐induced vertical heat flux, showing strong upward heat flux in ocean frontal regions such as the western boundary current regions. Using the Gulf Stream Extension region as an example, we estimate (1) the Stern‐Ekman pumping induced eddy heat flux is 23% and 12% of the total vertical eddy heat flux at 50 m depth during summer and winter, respectively; (2) the classical Ekman pumping accounts for 82% and 88% of the Stern‐Ekman pumping induced eddy heat flux at 50 m during summer and winter, respectively. The second finding indicates eddy current feedback on wind stress is the primary cause for the upward eddy heat flux generated by Ekman pumping.
An Initial Collision of India and Asia in the Equatorial Humid Belt
Authors: Yi Zhiyu , Wang Tianyue , Meert Joseph G. , Zhao Qian , Liu Yushu 
Published: May 2021

AbstractPaleocene lavas of the Dianzhong Formation preserved in the Linzhou Basin of South Tibet provide a unique opportunity to constrain the initial geometry of the India‐Asia collision; however, earlier studies argued a complex magnetic signature resulting from thermal and/or chemical remagnetizations. To better characterize the remanences obtained from the Dianzhong lavas, we carried out an intraformational conglomerate test on a previously‐studied section in the Linzhou Basin. The positive conglomerate test suggests that the characteristic remanences reported from the Dianzhong Formation are primary. The updated Paleocene pole confirms a paleolatitude of 6.7° ± 4.4°N for the Lhasa terrane and positions the southern margin of Asia in the equatorial humid belt. An initial collision, between India, Asia and an intra‐oceanic arc in the equatorial humid belt, may have intensified silicate weathering and resulted in an extra consummation of carbon dioxide, which contributes to a long‐term cooling of the Earth during the Cenozoic.
Activities of Small‐Scale Gravity Waves in the Upper Mesosphere Observed From Meteor Radar at King Sejong Station, Antarctica (62.22°S, 58.78°W) and Their Potential Sources
Authors: Song B.‐G. , Song I.‐S. , Chun H.‐Y. , Lee C. , Kam H. , Kim Y. H. , Kang M.‐J. , Hindley N. P. , Mitchell N. J. 
Published: May 2021

AbstractGravity wave (GW) activities in the upper mesosphere (80–100 km) and their potential sources are investigated using meteor radar observations at King Sejong Station, Antarctica (KSS; 62.22°S, 58.78°W) during recent 14 years (2007–2020). GW activities are estimated by horizontal wind variances of small‐scale GWs (periods <2 h, horizontal wavelength <400 km, or vertical wavelength <3–5 km). The wind variances show clear semiannual variations with maxima at solstices, and annual variations are also seen above z = 90 km. The deseasonalized wind variances at z = 96.8 km have a statistically significant periodicity of ∼11 years that can be associated with solar cycle variations. Three major potential GW sources in the lower atmosphere are examined. Orography is a potential source of GWs in winter and autumn, when the basic‐state wind is westerly from the surface up to the mesosphere. The residual of the nonlinear balance equation (RNBE) at 5 hPa, a diagnostic of the GWs associated with jet stream, is the largest in winter and has a secondary maximum in spring. The correlation between the observed GWs and RNBE is significant in equinoxes, while correlation is low in winter. Deep convection in storm tracks is a potential source in autumn and winter. Secondary GWs generated in the mesosphere can also be observed in the upper mesosphere. Ray‐tracing analysis for airglow images observed at KSS indicates that secondary GWs are mostly generated in winter mesosphere, which may be associated with the breaking of orographic GWs.
Effects of circulatory arrest and cardiopulmonary bypass on cerebral autoregulation in neonatal swine
Authors: Padawer-Curry Jonah A. , Volk Lindsay E. , Mavroudis Constantine D. , Ko Tiffany S. , Morano Vincent C. , Busch David R. , Rosenthal Tami M. , Melchior Richard W. , Shade Brandon C. , Schiavo Kellie L. , Boorady Timothy W. , Schmidt Alexander L. , Andersen Kristen N. , Breimann Jake S. , Jahnavi Jharna , Mensah-Brown Kobina G. , Yodh Arjun G. , Mascio Christopher E. , Kilbaugh Todd J. , Licht Daniel J. , White Brian R. , Baker Wesley B. 
Published: May 2021

Abstract
Background
Cerebral autoregulation mechanisms help maintain adequate cerebral blood flow (CBF) despite changes in cerebral perfusion pressure. Impairment of cerebral autoregulation, during and after cardiopulmonary bypass (CPB), may increase risk of neurologic injury in neonates undergoing surgery. In this study, alterations of cerebral autoregulation were assessed in a neonatal swine model probing four perfusion strategies.

Methods
Neonatal swine (n = 25) were randomized to continuous deep hypothermic cardiopulmonary bypass (DH-CPB, n = 7), deep hypothermic circulatory arrest (DHCA, n = 7), selective cerebral perfusion (SCP, n = 7) at deep hypothermia, or normothermic cardiopulmonary bypass (control, n = 4). The correlation coefficient (LDx) between laser Doppler measurements of CBF and mean arterial blood pressure was computed at initiation and conclusion of CPB. Alterations in cerebral autoregulation were assessed by the change between initial and final LDx measurements.

Results
Cerebral autoregulation became more impaired (LDx increased) in piglets that underwent DH-CPB (initial LDx: median 0.15, IQR [0.03, 0.26]; final: 0.45, [0.27, 0.74]; p = 0.02). LDx was not altered in those undergoing DHCA (p > 0.99) or SCP (p = 0.13). These differences were not explained by other risk factors.

Conclusions
In a validated swine model of cardiac surgery, DH-CPB had a significant effect on cerebral autoregulation, whereas DHCA and SCP did not.

Impact

Approximately half of the patients who survive neonatal heart surgery with cardiopulmonary bypass (CPB) experience neurodevelopmental delays. This preclinical investigation takes steps to elucidate and isolate potential perioperative risk factors of neurologic injury, such as impairment of cerebral autoregulation, associated with cardiac surgical procedures involving CPB.

We demonstrate a method to characterize cerebral autoregulation during CPB pump flow changes in a neonatal swine model of cardiac surgery.

Cerebral autoregulation was not altered in piglets that underwent deep hypothermic circulatory arrest (DHCA) or selective cerebral perfusion (SCP), but it was altered in piglets that underwent deep hypothermic CBP.
The role of ferroptosis in breast cancer patients: a comprehensive analysis
Authors: Wu Zeng-Hong , Tang Yun , Yu Hong , Li Hua-Dong 
Published: May 2021

AbstractBreast cancer (BC) affects the breast tissue and is the second most common cause of mortalities among women. Ferroptosis is an iron-dependent cell death mode that is characterized by intracellular accumulation of reactive oxygen species (ROS). We constructed a prognostic multigene signature based on ferroptosis-associated differentially expressed genes (DEGs). Moreover, we comprehensively analyzed the role of ferroptosis-associated miRNAs, lncRNAs, and immune responses. A total of 259 ferroptosis-related genes were extracted. KEGG function analysis of these genes revealed that they were mainly enriched in the HIF-1 signaling pathway, NOD-like receptor signaling pathway, central carbon metabolism in cancer, and PPAR signaling pathway. Fifteen differentially expressed genes (ALOX15, ALOX15B, ANO6, BRD4, CISD1, DRD5, FLT3, G6PD, IFNG, NGB, NOS2, PROM2, SLC1A4, SLC38A1, and TP63) were selected as independent prognostic factors for BC patients. Moreover, T cell functions, including the CCR score, immune checkpoint, cytolytic activity, HLA, inflammation promotion, para-inflammation, T cell co-stimulation, T cell co-inhibition, and type II INF responses were significantly different between the low-risk and high-risk groups of the TCGA cohort. Immune checkpoints between the two groups revealed that the expressions of PDCD-1 (PD-1), CTLA4, LAG3, TNFSF4/14, TNFRSF4/8/9/14/18/25, and IDO1/2 among others were significantly different. A total of 1185 ferroptosis-related lncRNAs and 219 ferroptosis-related miRNAs were also included in this study. From the online database, we identified novel ferroptosis-related biomarkers for breast cancer prognosis. The findings of this study provide new insights into the development of new reliable and accurate cancer treatment options.
Super-resolved visualization of single DNA-based tension sensors in cell adhesion
Authors: Schlichthaerle Thomas , Lindner Caroline , Jungmann Ralf 
Published: May 2021

AbstractCell-extracellular matrix sensing plays a crucial role in cellular behavior and leads to the formation of a macromolecular protein complex called the focal adhesion. Despite their importance in cellular decision making, relatively little is known about cell-matrix interactions and the intracellular transduction of an initial ligand-receptor binding event on the single-molecule level. Here, we combine cRGD-ligand-decorated DNA tension sensors with DNA-PAINT super-resolution microscopy to study the mechanical engagement of single integrin receptors and the downstream influence on actin bundling. We uncover that integrin receptor clustering is governed by a non-random organization with complexes spaced at 20–30 nm distances. The DNA-based tension sensor and analysis framework provide powerful tools to study a multitude of receptor-ligand interactions where forces are involved in ligand-receptor binding.
Single-keratinocyte transcriptomic analyses identify different clonal types and proliferative potential mediated by FOXM1 in human epidermal stem cells
Authors: Enzo Elena , Secone Seconetti Alessia , Forcato Mattia , Tenedini Elena , Polito Maria Pia , Sala Irene , Carulli Sonia , Contin Roberta , Peano Clelia , Tagliafico Enrico , Bicciato Silvio , Bondanza Sergio , De Luca Michele 
Published: May 2021

AbstractAutologous epidermal cultures restore a functional epidermis on burned patients. Transgenic epidermal grafts do so also in genetic skin diseases such as Junctional Epidermolysis Bullosa. Clinical success strictly requires an adequate number of epidermal stem cells, detected as holoclone-forming cells, which can be only partially distinguished from the other clonogenic keratinocytes and cannot be prospectively isolated. Here we report that single-cell transcriptome analysis of primary human epidermal cultures identifies categories of genes clearly distinguishing the different keratinocyte clonal types, which are hierarchically organized along a continuous, mainly linear trajectory showing that stem cells sequentially generate progenitors producing terminally differentiated cells. Holoclone-forming cells display stem cell hallmarks as genes regulating DNA repair, chromosome segregation, spindle organization and telomerase activity. Finally, we identify FOXM1 as a YAP-dependent key regulator of epidermal stem cells. These findings improve criteria for measuring stem cells in epidermal cultures, which is an essential feature of the graft.
Differential chromatin binding of the lung lineage transcription factor NKX2-1 resolves opposing murine alveolar cell fates in vivo
Authors: Little Danielle R. , Lynch Anne M. , Yan Yun , Akiyama Haruhiko , Kimura Shioko , Chen Jichao 
Published: May 2021

AbstractDifferential transcription of identical DNA sequences leads to distinct tissue lineages and then multiple cell types within a lineage, an epigenetic process central to progenitor and stem cell biology. The associated genome-wide changes, especially in native tissues, remain insufficiently understood, and are hereby addressed in the mouse lung, where the same lineage transcription factor NKX2-1 promotes the diametrically opposed alveolar type 1 (AT1) and AT2 cell fates. Here, we report that the cell-type-specific function of NKX2-1 is attributed to its differential chromatin binding that is acquired or retained during development in coordination with partner transcriptional factors. Loss of YAP/TAZ redirects NKX2-1 from its AT1-specific to AT2-specific binding sites, leading to transcriptionally exaggerated AT2 cells when deleted in progenitors or AT1-to-AT2 conversion when deleted after fate commitment. Nkx2-1 mutant AT1 and AT2 cells gain distinct chromatin accessible sites, including those specific to the opposite fate while adopting a gastrointestinal fate, suggesting an epigenetic plasticity unexpected from transcriptional changes. Our genomic analysis of single or purified cells, coupled with precision genetics, provides an epigenetic basis for alveolar cell fate and potential, and introduces an experimental benchmark for deciphering the in vivo function of lineage transcription factors.
Physiological and biochemical responses of two precious Carpinus species to high-concentration NO2 stress and their natural recovery
Authors: Sheng Qianqian , Song Min , Zhu Zunling , Cao Fuliang 
Published: May 2021

AbstractCarpinus betulus and Carpinus putoensis are precious species in the world. Studies on the ecosystem function of the two species are rare. This study investigated the physiological and biochemical responses of C. betulus and C. putoensis to NO2 stress and their natural recovery. C. betulus and C. putoensis seedlings underwent fumigation with 12.0 mg/m3 NO2 for 0, 1, 6, 12, 24, 48, and 72 h, respectively. Then, the plants were allowed to recover at room temperature for 30 d. Physiological and biochemical changes in the leaves were compared between the two species. In terms of peroxidase (POD) activity, the damage response of C. betulus under NO2 stress appeared later than that of C. putoensis. The soluble protein content of C. betulus was noticeably higher than that of C. putoensis, and C. betulus exhibited more stable membrane lipoperoxidation. The tendency of the changes in nitrate reductase of C. betulus was less noticeable than that of C. putoensis. The variation amplitudes of N, K, Mg, Zn and Mn in the leaves of C. putoensis were greater than those of C. betulus. C. putoensis showed more sensitive metabolisms in response to NO2 stress compared with C. betulus. High-concentration NO2 caused damage to C. betulus and C. putoensis was reversible, and both species returned to normal growth via their own metabolism after 30-d recovery. The results of this study may provide useful reference data for quantitative assessment of the ecosystem function of C. betulus and C. putoensis and for their scientific application in urban greening.
Demonstration of high-speed and low-complexity continuous variable quantum key distribution system with local local oscillator
Authors: Ren Shengjun , Yang Shuai , Wonfor Adrian , White Ian , Penty Richard 
Published: May 2021

AbstractWe present an experimental demonstration of the feasibility of the first 20 + Mb/s Gaussian modulated coherent state continuous variable quantum key distribution system with a locally generated local oscillator at the receiver (LLO-CVQKD). To increase the signal repetition rate, and hence the potential secure key rate, we equip our system with high-performance, wideband devices and design the components to support high repetition rate operation. We have successfully trialed the signal repetition rate as high as 500 MHz. To reduce the system complexity and correct for any phase shift during transmission, reference pulses are interleaved with quantum signals at Alice. Customized monitoring software has been developed, allowing all parameters to be controlled in real-time without any physical setup modification. We introduce a system-level noise model analysis at high bandwidth and propose a new ‘combined-optimization’ technique to optimize system parameters simultaneously to high precision. We use the measured excess noise, to predict that the system is capable of realizing a record 26.9 Mb/s key generation in the asymptotic regime over a 15 km signal mode fibre. We further demonstrate the potential for an even faster implementation.
Laser-induced structural modification in calcium aluminosilicate glasses using molecular dynamic simulations
Authors: Locker Sean , Goyal Sushmit , McKenzie Matthew E. , Sundaram S. K. , Ungaro Craig 
Published: May 2021

AbstractGlass structures of multicomponent oxide systems (CaO–Al2O3–SiO2) are studied using a simulated pulsed laser with molecular dynamics. The short- and intermediate-range order structures revealed a direct correlation between the transformation of Al(IV) to Al(V), regions of increased density following laser processing, inherent reduction in the average T–O–T (T = Al, Si) angle, and associated elongation of the T–O bonding distance. Variable laser pulse energies were simulated across calcium aluminosilicate glasses with high silica content (50–80%) to identify densification trends attributed to composition and laser energy. High-intensity pulsed laser effects on fictive temperature and shockwave promotion are discussed in detail for their role in glass densification. Laser-induced structural changes are found to be highly dependent on pulse energy and glass chemistry.
Structural, magnetic, and gigahertz-range electromagnetic wave absorption properties of bulk Ni–Zn ferrite
Authors: Derakhshani M. , Taheri-Nassaj E. , Jazirehpour M. , Masoudpanah S. M. 
Published: May 2021

AbstractNickel–zinc ferrite (Ni0.5Zn0.5Fe2O4) powders were prepared by the conventional solid-state route and sintered at 1100 and 1300 °C for utilization as a tile electromagnetic wave absorber. Structural, magnetic, and microwave absorption properties were investigated by characterization techniques of X-ray diffraction, thermogravimetric analysis, Raman spectroscopy, electron microscopy, vibrating sample magnetometry, and vector network analyzer. The samples sintered at 1300 °C showed high magnetic saturation of 87 emu/g and low coercivity of 4 Oe. Electromagnetic investigations exhibit high reflection losses up to − 48.1 dB at certain high and low gigahertz frequencies, as clearly depicted in the 3D contour plot. The optimized condition between reflection loss, thickness, and bandwidth revealed a reflection loss of about − 36.1 dB at the matching thickness of 3.7 mm for the X-band. Furthermore, the effective working bandwidth at − 10 dB was up to ~ 7.1 GHz for the minimum thickness of 4.3 mm, which thoroughly covered the C-band. The microwave absorption performance of the well-sintered Ni–Zn ferrite was attributed to the incorporation of dielectric and magnetic loss mechanisms in which the magnetic part prevails.
Gene-environment dependencies lead to collider bias in models with polygenic scores
Authors: Akimova Evelina T. , Breen Richard , Brazel David M. , Mills Melinda C. 
Published: May 2021

AbstractThe application of polygenic scores has transformed our ability to investigate whether and how genetic and environmental factors jointly contribute to the variation of complex traits. Modelling the complex interplay between genes and environment, however, raises serious methodological challenges. Here we illustrate the largely unrecognised impact of gene-environment dependencies on the identification of the effects of genes and their variation across environments. We show that controlling for heritable covariates in regression models that include polygenic scores as independent variables introduces endogenous selection bias when one or more of these covariates depends on unmeasured factors that also affect the outcome. This results in the problem of conditioning on a collider, which in turn leads to spurious associations and effect sizes. Using graphical and simulation methods we demonstrate that the degree of bias depends on the strength of the gene-covariate correlation and of hidden heterogeneity linking covariates with outcomes, regardless of whether the main analytic focus is mediation, confounding, or gene × covariate (commonly gene × environment) interactions. We offer potential solutions, highlighting the importance of causal inference. We also urge further caution when fitting and interpreting models with polygenic scores and non-exogenous environments or phenotypes and demonstrate how spurious associations are likely to arise, advancing our understanding of such results.