bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tracking the Stratosphere‐to‐Surface Impact of Sudden Stratospheric Warmings
Authors: Hall Richard J. , Mitchell Daniel M. , Seviour William J. M. , Wright Corwin J. 
Published: December 2020

AbstractSudden stratospheric warming (SSW) events are extreme atmospheric regimes which can have a signature in surface weather up to 40 days after event onset in the stratosphere. SSWs can be classified as either vortex splitting or vortex displacement events, with the nature and timing of the surface impact potentially being different between the two. In this study, using ERA40/Interim reanalysis data, we develop a simple empirical downward tracking algorithm which for the first time allows us to estimate the time of surface impact for individual SSW events. We show that the surface impact following splitting events is, on average, about 1 week earlier than following displacement events, albeit with considerable variability. By compositing tropospheric responses around the identified date of surface impact, rather than around the central stratospheric onset date as common in previous studies, we can better constrain the surface signal of SSWs. We find that while the difference in North Atlantic Oscillation anomalies between split and displacement vortices is small, surface temperature anomalies over northwest Europe and northern Eurasia are significantly colder for splitting events, particularly over the UK just prior to the surface impact date. Displacement events on average are wetter over Northwest Europe around the time of surface impact, consistent with the jet stream being displaced further south in response to split events. Our downtracking algorithm can be used with any reanalyzes and gridded model data, and therefore will be a valuable tool for use with the latest climate models.
Magnetic Induction Responses of Jupiter's Ocean Moons Including Effects From Adiabatic Convection
Authors: Vance S. D. , Styczinski M. J. , Bills B. G. , Cochrane C. J. , Soderlund K. M. , Gómez‐Pérez N. , Paty C. 
Published: December 2020

AbstractPrior analyses of oceanic magnetic induction within Jupiter's large icy moons have assumed uniform electrical conductivity. However, the phase and amplitude responses of the induced fields will be influenced by the natural depth‐dependence of the electrical conductivity. Here, we examine the amplitudes and phase delays for magnetic diffusion in modeled oceans of Europa, Ganymede, and Callisto. For spherically symmetric configurations, we consider thermodynamically consistent interior structures that include realistic electrical conductivity along the oceans' adiabatic temperature profiles. Conductances depend strongly on salinity, especially in the large moons. The induction responses of the adiabatic profiles differ from those of oceans with uniform conductivity set to values at the ice–ocean interface, or to the mean values of the adiabatic profile, by more than 10% for some signals. We also consider motionally induced magnetic fields generated by convective fluid motions within the oceans, which might optimistically be used to infer ocean flows or, pessimistically, act to bias the ocean conductivity inversions. Our upper‐bound scaling estimates suggest this effect may be important at Europa and Ganymede, with a negligible contribution at Callisto. Based on end‐member ocean compositions, we quantify the magnetic induction signals that might be used to infer the oxidation state of Europa's ocean and to investigate stable liquids under high‐pressure ices in Ganymede and Callisto. Fully exploring this parameter space for the sake of planned missions requires thermodynamic and electrical conductivity measurements in fluids at low temperature and to high‐salinity and pressure as well as modeling of motional induction responses.
Extensive Urban Green Roof Shows Consistent Annual Net Uptake of Carbon as Documented by 5 Years of Eddy‐Covariance Flux Measurements
Authors: Konopka J. , Heusinger J. , Weber S. 
Published: December 2020

AbstractVegetated roofs or green roofs may supply a number of different urban ecosystem services such as thermal regulation of local air temperature by evaporative cooling or climate change mitigation by sequestration of CO2. However, knowledge about the annual and seasonal variations of green roof carbon uptake due to changes in meteorological conditions and water availability remains scarce. We studied the annual variation of net ecosystem exchange (NEE) by eddy‐covariance flux measurements during a 5‐year period from 2014 to 2019 on a large and unirrigated green roof at the Berlin‐Brandenburg airport (BER) in Berlin, Germany. The roof vegetation was dominated by Sedum species and herbs. The BER green roof showed net uptake of carbon in each of the 5 study years with an average uptake of −141.1 g C m−2 y−1 and an average measurement uncertainty of ±15.5 g C m−2 y−1. The NEE, however, was characterized by significant interannual variation in which the maximum annual uptake of −189 g C m−2 y−1 in a year with above average precipitation roughly doubles the minimum uptake of −95 g C m−2 y−1 in a dry year. The variation of NEE was a function of the annual amount of precipitation and the frequency of rainfall, that is, the number of dry days per year (DDY). The roof might lose its carbon uptake function in a warmer future climate with an increasing number of DDY. Sustainable irrigation of the roof (e.g., rainwater harvesting) could help to maintain the carbon uptake function of the green roof vegetation.
Coastal Forest Seawater Exposure Increases Stem Methane Concentration
Authors: Norwood Matthew J. , Ward Nicholas D. , McDowell Nate G. , Myers‐Pigg Allison N. , Bond‐Lamberty Ben , Indivero Julia , Pennington Stephanie , Wang Wenzhi , Kirwan Matt , Hopple Anya M. , Megonigal J. Patrick 
Published: December 2020

AbstractMethane (CH4) exchange between trees and the atmosphere has recently emerged as an important, but poorly quantified process regulating global climate. The sources (soil and/or tree) and mechanisms driving the increase of CH4 in trees and degassing to the atmosphere are inadequately understood, particularly for coastal forests facing increased exposure to seawater. We investigated the eco‐physiological relationship between tree stem wood density, soil and stem oxygen saturation (an indicator of redox state), soil and stem CH4 concentrations, soil and stem carbon dioxide (CO2) concentrations, and soil salinity in five forests along the United States coastline. We aim to evaluate the mechanisms underlying greenhouse gas increase in trees and the influence of seawater exposure on stem CH4 accumulation. Seawater exposure corresponded with decreased tree survival and increased tree stem methane. Tree stem wood density was significantly correlated with increased stem CH4 in seawater exposed gymnosperms, indicating that dying gymnosperm trees may accumulate higher levels of CH4 in association with seawater flooding. Further, we found that significant differences in seawater exposed and unexposed gymnosperm tree populations are associated with increased soil and stem CH4 and CO2, indicating that seawater exposure significantly impacts soil and stem greenhouse gas abundance. Our results provide new insight into the potential mechanisms driving tree CH4 accumulation within gymnosperm coastal forests.
STAT3 ameliorates cognitive deficits by positively regulating the expression of NMDARs in a mouse model of FTDP-17
Authors: Hong Xiao-Yue , Wan Hua-Li , Li Ting , Zhang Bing-Ge , Li Xiao-Guang , Wang Xin , Li Xiao , Liu Qian , Chen Chong-Yang , Yang Ying , Wang Qun , Li Shu-Peng , Yu Hao , Wang Jian-Zhi , Yang Xi-Fei , Liu Gong-Ping 
Published: December 2020

AbstractIn tauopathies, memory impairment positively strongly correlates with the amount of abnormal tau aggregates; however, how tau accumulation induces synapse impairment is unclear. Recently, we found that human tau accumulation activated Signal Transduction and Activator of Transcription-1 (STAT1) to inhibit the transcription of synaptic N-methyl-D-aspartate receptors (NMDARs). Here, overexpressing human P301L mutant tau (P301L-hTau) increased the phosphorylated level of Signal Transduction and Activator of Transcription-3 (STAT3) at Tyr705 by JAK2, which would promote STAT3 translocate into the nucleus and activate STAT3. However, STAT3 was found mainly located in the cytoplasm. Further study found that P301L-htau acetylated STAT1 to bind with STAT3 in the cytoplasm, and thus inhibited the nuclear translocation and inactivation of STAT3. Knockdown of STAT3 in STAT3flox/flox mice mimicked P301L-hTau-induced suppression of NMDARs expression, synaptic and memory impairments. Overexpressing STAT3 rescued P301L-hTau-induced synaptic and cognitive deficits by increasing NMDARs expression. Further study proved that STAT3 positively regulated NMDARs transcription through direct binding to the specific GAS element of NMDARs promoters. These findings indicate that accumulated P301L-hTau inactivating STAT3 to suppress NMDARs expression, revealed a novel mechanism for tau-associated synapse and cognition deficits, and STAT3 will hopefully serve as a potential pharmacological target for tauopathies treatment.
m6A RNA methylation-mediated HNF3γ reduction renders hepatocellular carcinoma dedifferentiation and sorafenib resistance
Authors: Zhou Tengfei , Li Shichao , Xiang Daimin , Liu Junyu , Sun Wen , Cui Xiuliang , Ning Beifang , Li Xiao , Cheng Zhuo , Jiang Weiqi , Zhang Cheng , Liang Xijun , Li Liang , Cheng Xin , Hui Liu , Wang Hongyang , Ding Jin 
Published: December 2020

AbstractHepatocyte nuclear factor 3γ (HNF3γ) is a hepatocyte nuclear factor, but its role and clinical significance in hepatocellular carcinoma (HCC) remain unclear. Herein, we report that HNF3γ expression is downregulated in patient HCC and inversely correlated with HCC malignancy and patient survival. Moreover, our data suggested that the HNF3γ reduction in HCC could be mediated by METTL14-dependent m6A methylation of HNF3γ mRNA. HNF3γ expression was increased during hepatic differentiation and decreased in dedifferentiated HCC cells. Interestingly, HNF3γ delivery promoted differentiation of not only HCC cells but also liver CSCs, which led to suppression of HCC growth. Mechanistic analysis suggested an HNF3γ-centered regulatory network that includes essential liver differentiation-associated transcription factors and functional molecules, which could synergistically facilitate HCC cell differentiation. More importantly, enforced HNF3γ expression sensitized HCC cells to sorafenib-induced growth inhibition and cell apoptosis through transactivation of OATP1B1 and OATP1B3 expression, which are major membrane transporters for sorafenib uptake. Clinical investigation showed that patient-derived HCC xenografts with high HNF3γ expression exhibited a sorafenib response and patients with high HCC HNF3γ levels benefited from sorafenib therapy. Together, these results suggest that HNF3γ plays an essential role in HCC differentiation and may serve as a therapeutic target and predictor of sorafenib benefit in patients.
Kindlin-2 regulates skeletal homeostasis by modulating PTH1R in mice
Authors: Fu Xuekun , Zhou Bo , Yan Qinnan , Tao Chu , Qin Lei , Wu Xiaohao , Lin Sixiong , Chen Sheng , Lai Yumei , Zou Xuenong , Shao Zengwu , Wang Meiqing , Chen Di , Jin Wenfei , Song Youqiang , Cao Huiling , Zhang Ge , Xiao Guozhi 
Published: December 2020

AbstractIn vertebrates, the type 1 parathyroid hormone receptor (PTH1R) is a critical regulator of skeletal development and homeostasis; however, how it is modulated is incompletely understood. Here we report that deleting Kindlin-2 in osteoblastic cells using the mouse 10-kb Dmp1-Cre largely neutralizes the intermittent PTH-stimulated increasing of bone volume fraction and bone mineral density by impairing both osteoblast and osteoclast formation in murine adult bone. Single-cell profiling reveals that Kindlin-2 loss increases the proportion of osteoblasts, but not mesenchymal stem cells, chondrocytes and fibroblasts, in non-hematopoietic bone marrow cells, with concomitant depletion of osteoblasts on the bone surfaces, especially those stimulated by PTH. Furthermore, haploinsufficiency of Kindlin-2 and Pth1r genes, but not that of either gene, in mice significantly decreases basal and, to a larger extent, PTH-stimulated bone mass, supporting the notion that both factors function in the same genetic pathway. Mechanistically, Kindlin-2 interacts with the C-terminal cytoplasmic domain of PTH1R via aa 474–475 and Gsα. Kindlin-2 loss suppresses PTH induction of cAMP production and CREB phosphorylation in cultured osteoblasts and in bone. Interestingly, PTH promotes Kindlin-2 expression in vitro and in vivo, thus creating a positive feedback regulatory loop. Finally, estrogen deficiency induced by ovariectomy drastically decreases expression of Kindlin-2 protein in osteocytes embedded in the bone matrix and Kindlin-2 loss essentially abolishes the PTH anabolic activity in bone in ovariectomized mice. Thus, we demonstrate that Kindlin-2 functions as an intrinsic component of the PTH1R signaling pathway in osteoblastic cells to regulate bone mass accrual and homeostasis.
CircRNA-SORE mediates sorafenib resistance in hepatocellular carcinoma by stabilizing YBX1
Authors: Xu Junjie , Ji Lin , Liang Yuelong , Wan Zhe , Zheng Wei , Song Xiaomin , Gorshkov Kirill , Sun Qiming , Lin Hui , Zheng Xueyong , Chen Jiang , Jin Ren-an , Liang Xiao , Cai Xiujun 
Published: December 2020

AbstractSorafenib is the first-line chemotherapeutic therapy for advanced hepatocellular carcinoma (HCC). However, sorafenib resistance significantly limits its therapeutic efficacy, and the mechanisms underlying resistance have not been fully clarified. Here we report that a circular RNA, circRNA-SORE (a circular RNA upregulated in sorafenib-resistant HCC cells), plays a significant role in sorafenib resistance in HCC. We found that circRNA-SORE is upregulated in sorafenib-resistant HCC cells and depletion of circRNA-SORE substantially increases the cell-killing ability of sorafenib. Further studies revealed that circRNA-SORE binds the master oncogenic protein YBX1 in the cytoplasm, which prevents YBX1 nuclear interaction with the E3 ubiquitin ligase PRP19 and thus blocks PRP19-mediated YBX1 degradation. Moreover, our in vitro and in vivo results suggest that circRNA-SORE is transported by exosomes to spread sorafenib resistance among HCC cells. Using different HCC mouse models, we demonstrated that silencing circRNA-SORE by injection of siRNA could substantially overcome sorafenib resistance. Our study provides a proof-of-concept demonstration for a potential strategy to overcome sorafenib resistance in HCC patients by targeting circRNA-SORE or YBX1.
Emulation of biphasic plasticity in retinal electrical synapses for light-adaptive pattern pre-processing
Authors: Wu Lindong , Wang Zongwei , Wang Bowen , Chen Qingyu , Bao Lin , Yu Zhizhen , Yang Yunfan , Ling Yaotian , Qin Yabo , Tang Kechao , Cai Yimao , Huang Ru 
Published: December 2020

This work demonstrates the emulation of biphasic plasticity in the electrical synapses by integrating the Ag-based memristor with a photosensitive element to form an optical pre-processing unit (OPU).
I‐HPO‐CDSK: An improved chaotic communication scheme for high reliability and effectivity
Authors: Duan Jun‐Yi , Yang Hua 
Published: December 2020

AbstractBy transmitting 2‐bits orthogonal information signal in parallel, compared with phase‐orthogonality CDSK (PO‐CDSK), high‐data‐rate PO‐CDSK (HPO‐CDSK) has double spectral efficiency. Unfortunately, the additional information will cause more noise interference during correlation detection in HPO‐CDSK. The study of HPO‐CDSK is extended and improved HPO‐CDSK (I‐HPO‐CDSK) is proposed to obtain high reliability and effectiveness. By virtue of the theorem that the integral of the sine and cosine functions in a period is 0, in I‐HPO‐CDSK, 3‐bits information can be transmitted in parallel and will not cause ISI components. Moreover, compared with HPO‐CDSK, I‐HPO‐CDSK can decrease noise interference. Results show that, due to less interference and 3‐bits information transmitting in parallel, I‐HPO‐CDSK has better BER performance and spectral efficiency than those of previous chaotic communication schemes, such as PO‐CDSK and HPO‐CDSK.
Channel estimation using variational Bayesian learning for multi‐user mmWave MIMO systems
Authors: Xiao Bo , Huang Pingmu , Lin Zhipeng , Zeng Jie , Lv Tiejun 
Published: December 2020

AbstractThis paper presents a novel variational Bayesian learning‐based channel estimation scheme for hybrid pre‐coding‐employed wideband multiuser millimetre wave multiple‐input multiple‐output communication systems. We first propose a frequency variational Bayesian algorithm, which leverages common sparsity of different sub‐carriers in the frequency domain. The algorithm shares all the information of the support sets from the measurement matrices, significantly improving channel estimation accuracy. To enhance robustness of the frequency variational Bayesian algorithm, we develop a hierarchical Gaussian prior channel model, which employs an identify‐and‐reject strategy to deal with random outliers imposed by hardware impairments. A support selection frequency variational Bayesian channel estimation algorithm is also proposed, which adaptively selects support sets from the measurement matrices. As a result, the overall computational complexity can be reduced. Validated by the Bayesian Cramér‐Rao bound, simulation results show that, both frequency variational Bayesian and support selection‐frequency variational Bayesian algorithms can achieve higher channel estimation accuracy than existing methods. Furthermore, compared with frequency variational Bayesian, support selection‐frequency variational Bayesian requires significantly lower computational complexity, and hence, it is more practical for channel estimation applications.
A novel non‐unit protection scheme for HVDC transmission lines based on multi‐resolution morphology gradient
Authors: Raghpoor Vahid , Mehrabi‐Kooshki Mohammad , Razzaghi Reza 
Published: December 2020

AbstractThis paper presents a novel non‐unit protection scheme for the protection of LCC‐HVDC transmission lines. The fault‐generated travelling waves at the faulty line ends are filtered by a filter–reactor unit. The filtered current waveforms are then processed by a multi‐resolution morphological gradient and are used by a fast non‐unit protection scheme for LCC‐HVDC transmission lines. The proposed method does not require communication links between transmission line ends and uses only current signals with a low sampling rate of 10 kHz. In addition, the proposed scheme is computationally efficient, making it suitable for practical applications. The performance of the proposed protection scheme is validated by comprehensive simulation studies as well as field data on a bipolar LCC‐HVDC system. Both simulation and field data test results verify the accurate performance of the proposed method for different internal fault conditions, including high fault resistances up to 1000 Ω. Furthermore, the proposed scheme is robust against external DC and AC faults, change of sampling frequency and data window length, non‐ideal faults, change of power flow, change of DC filter parameters and smoothing reactor, change of operation mode, and measurement noise.
Deep residual deconvolutional networks for defocus blur detection
Authors: Zeng Kai , Wang Yaonan , Mao Jianxu , Zhou Xianen 
Published: December 2020

AbstractAccurate defocus blur detection has instigated wide research interest for the last few years. However, it is still a meaningful yet challenging machine vision task, and most methods rely on prior knowledge. Convolutional neural networks have proved the huge success for different tasks within the computer vision, and machine learning flew. A simple yet effective method of defocus blur detection was proposed in this paper, which by applying the deep residual convolutional encoder‐decoder network. The aims of DRDN is to automatically generate pixel‐level predictions for defocus blur images, and reconstruct output detection results of the same size as the input, which by performing several deconvolution operations at multiple scales through the transposed convolution, and skip connection. Afterwards, we used the slide window detection strategy and traversed the input image with a certain stride. Experiments on challenging benchmarks of defocus blur detection show that our algorithm achieved state‐of‐the‐art performance, and powerfully balanced the detection accuracy, and detection time.
Finger vein recognition algorithm under reduced field of view
Authors: Jin Jian , Di Si , Li Weijian , Sun Xuetong , Wang Xudi 
Published: December 2020

AbstractAlgorithms for finger vein recognition methods are generally designed based on greyscale images containing vein distributions, but greyscale inhomogeneities and non‐venous texture structures often adversely affect the recognition results. Besides, the performance of the algorithm when the field of view is reduced has not been studied. Therefore, the aim of this paper is to propose an algorithm based on binary image, so as to minimize the interference of non‐venous factors in the identification process. We use the feature from accelerated segment test algorithm to detect feature points, and use gradient histogram to describe these feature points in a vectorized manner. In addition, we propose the concept of circular matching neighbourhood, and select the matching feature point pairs in this area. Then, the Euclidean distance and the number of correct matching pairs were comprehensively considered to increase the recognition rate of the algorithm. The algorithm was tested on the database of SDU‐MLA, FV‐USM and MMCBNU‐6000. The results show that the algorithm has certain advantages before and after the field of view is reduced. Therefore, this paper not only provides a new idea for finger vein recognition, but also has practical application value for the miniaturization of finger vein acquisition devices.
An improved symbol reduction technique based Huffman coder for efficient entropy coding in the transform coders
Authors: Thakur Vikrant Singh , Thakur Kavita , Gupta Shubhrata 
Published: December 2020

AbstractEntropy coding is the essential block of transform coders that losslessly converts the quantized transform coefficients into the bit‐stream suitable for transmission or storage. Usually, the entropy coders exhibit less compression capability than the lossy coding techniques. Hence, in the past decade, several efforts have been made to improve the compression capability of the entropy coding technique. Recently, a symbol reduction technique (SRT) based Huffman coder is developed to achieve higher compression than the existing entropy coders at similar complexity of the regular Huffman coder. However, the SRT‐based Huffman coding is not popular for the real‐time applications due to the improper negative symbol handling and the additional indexing issues, which restrict its compression gain at most 10–20% over the regular Huffman coder. Hence, in this paper, an improved SRT (ISRT) based Huffman coder is proposed to properly alleviate the deficiencies of the recent SRT‐based Huffman coder and to achieve higher compression gains. The proposed entropy coder is extensively evaluated on the ground of compression gain and the time complexity. The results show that the proposed ISRT‐based Huffman coder provides significant compression gain against the existing entropy coders with lower time consumptions.