bluuebunny/crossref_metadata_2025_split huggingface dataset:
Circulation and Hydrography in the Western South Atlantic Shelf and Export to the Deep Adjacent Ocean: 30°S to 40°S
Authors: Berden Giuliana , Charo Marcela , Möller Osmar O. , Piola Alberto R. 
Published: September 2020

AbstractHigh sea surface chlorophyll concentration on the Argentine Continental Shelf frequently extends to the deep ocean in the vicinity of the Brazil/Malvinas Confluence (BMC). The offshore transport of shelf waters likely plays a key role in the biogeochemical balance of the western South Atlantic and promotes the offshore transport of planktonic species. We analyze data from an oceanographic survey carried out in the western South Atlantic shelf between 31°S and 38°S in October 2013. We describe the distribution and circulation of the water masses and focus on the exchanges with the open ocean. On‐shelf subsurface intrusions of oceanic waters and river discharge supply nutrients to the shelf. A low‐salinity tongue of Río de la Plata (RDP) waters extends northward to 32°S. Below these waters Subantarctic and Subtropical Shelf Waters (SASW and STSW) meet to form the Subtropical Shelf Front. The main SASW branch, oversaturated in oxygen and with high‐fluorescence mixes with a detachment of Brazil Current waters at 38°S and is exported offshore along the BMC. A second branch of SASW reaches 33°S mixing along its way with RDP and STSW and returns southward after splitting into an onshore and an offshore branch. The offshore branch is exported to the open ocean through the BMC. These export routes are in overall qualitative agreement with those indicated by a high‐resolution reanalysis. We estimate a net off‐shelf transport (geostrophic [96.2%] plus Ekman [3.8%]) of 3.44 Sv to the open ocean between 32.1°S and 37.7°S. The majority of the offshore flow occurs between 34.7°S and 37.7°S.
Cooling and Moistening of the Planetary Boundary Layer in Interior Alaska Due to a Postfire Change in Surface Energy Exchange
Authors: Ueyama Masahito , Yamamori Takahiro , Iwata Hiroki , Harazono Yoshinobu 
Published: September 2020

Key Points

Regional climate via PBL dynamics was estimated using measurements of surface energy exchange and mixed‐layer model in interior Alaska
Regional cooling and moistening were estimated due to fire‐induced land cover change from a mature forest to postfire young forest
Albedo and increased evapotranspiration caused the regional cooling and moistening effects
Entrainment and Dynamics of Ocean‐Derived Impurities Within Europa's Ice Shell
Authors: Buffo J. J. , Schmidt B. E. , Huber C. , Walker C. C. 
Published: September 2020

AbstractCompositional heterogeneities within Europa's ice shell likely impact the dynamics and habitability of the ice and subsurface ocean, but the total inventory and distribution of impurities within the shell are unknown. In sea ice on Earth, the thermochemical environment at the ice‐ocean interface governs impurity entrainment into the ice. Here, we simulate Europa's ice‐ocean interface and bound the impurity load (1.053–14.72 g/kg [parts per thousand weight percent, or ppt] bulk ice shell salinity) and bulk salinity profile of the ice shell. We derive constitutive equations that predict ice composition as a function of the ice shell thermal gradient and ocean composition. We show that evolving solidification rates of the ocean and hydrologic features within the shell produce compositional variations (ice bulk salinities of 5–50% of the ocean salinity) that can affect the material properties of the ice. As the shell thickens, less salt is entrained at the ice‐ocean interface, which implies Europa's ice shell is compositionally homogeneous below ~1 km. Conversely, the solidification of water filled fractures or lenses introduces substantial compositional variations within the ice shell, creating gradients in mechanical and thermal properties within the ice shell that could help initiate and sustain geological activity. Our results suggest that ocean materials entrained within Europa's ice shell affect the formation of geologic terrain and that these structures could be confirmed by planned spacecraft observations.
Vertical Propagation of Wave Perturbations in the Middle Atmosphere on Mars by MAVEN/IUVS
Authors: Nakagawa Hiromu , Terada Naoki , Jain Sonal K. , Schneider Nicholas M. , Montmessin Franck , Yelle Roger V. , Jiang Fayu , Verdier Loic , England Scott L. , Seki Kanako , Fujiwara Hitoshi , Imamura Takeshi , Yoshida Nao , Kuroda Takeshi , Terada Kaori , Gröller Hannes , Deighan Justin , Jakosky Bruce M. 
Published: September 2020

AbstractThis work offers the first in‐depth study of the global characteristics of wave perturbations in temperature profiles at 20–140 km altitudes derived from the Imaging Ultraviolet Spectrograph (IUVS) onboard the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft. The peak amplitudes of waves seen in temperature profiles exceed 20% of the mean background, especially on the nightside, which is larger than those in Earth's mesosphere and thermosphere. The wave perturbations generate an instability layer around 70–100 km on the nightside, which potentially causes wave‐breaking and turbulences. Our results highlighted a seasonal variation in the latitudinal distribution of nightside perturbations. Amplitudes of wave perturbations were found to be large in the northern low‐latitude region and the southern polar region during the first half of the year (Ls = 0–180°). An increase of waves in the spectral density was found in southern low‐latitude regions in the latter half of the year (Ls = 180–360°). Vertical wavenumber spectral density in the Martian middle atmosphere shows a power‐law dependence with a logarithmic spectral slope of −3, similar to the features seen in the Earth's atmosphere. The derived spectral power density suggests the longer waves growing with height while the effective dissipation of shorter waves occurs. The strong CO2 15‐micron band cooling can effectively dissipate shorter waves. In contrast, the spectral power density at longer waves suggests an amplitude growth with height of unsaturated waves up to the lower thermosphere.
Telomere dysfunction activates YAP1 to drive tissue inflammation
Authors: Chakravarti Deepavali , Hu Baoli , Mao Xizeng , Rashid Asif , Li Jiexi , Li Jun , Liao Wen-ting , Whitley Elizabeth M. , Dey Prasenjit , Hou Pingping , LaBella Kyle A. , Chang Andrew , Wang Guocan , Spring Denise J. , Deng Pingna , Zhao Di , Liang Xin , Lan Zhengdao , Lin Yiyun , Sarkar Sharmistha , Terranova Christopher , Deribe Yonathan Lissanu , Blutt Sarah E. , Okhuysen Pablo , Zhang Jianhua , Vilar Eduardo , Nielsen Ole Haagen , Dupont Andrew , Younes Mamoun , Patel Kalyani R. , Shroyer Noah F. , Rai Kunal , Estes Mary K. , Wang Y. Alan , Bertuch Alison A. , DePinho Ronald A. 
Published: September 2020

AbstractGermline telomere maintenance defects are associated with an increased incidence of inflammatory diseases in humans, yet whether and how telomere dysfunction causes inflammation are not known. Here, we show that telomere dysfunction drives pATM/c-ABL-mediated activation of the YAP1 transcription factor, up-regulating the major pro-inflammatory factor, pro-IL-18. The colonic microbiome stimulates cytosolic receptors activating caspase-1 which cleaves pro-IL-18 into mature IL-18, leading to recruitment of interferon (IFN)-γ-secreting T cells and intestinal inflammation. Correspondingly, patients with germline telomere maintenance defects exhibit DNA damage (γH2AX) signaling together with elevated YAP1 and IL-18 expression. In mice with telomere dysfunction, telomerase reactivation in the intestinal epithelium or pharmacological inhibition of ATM, YAP1, or caspase-1 as well as antibiotic treatment, dramatically reduces IL-18 and intestinal inflammation. Thus, telomere dysfunction-induced activation of the ATM-YAP1-pro-IL-18 pathway in epithelium is a key instigator of tissue inflammation.
Single-cell sequencing reveals clonal expansions of pro-inflammatory synovial CD8 T cells expressing tissue-homing receptors in psoriatic arthritis
Authors: Penkava Frank , Velasco-Herrera Martin Del Castillo , Young Matthew D. , Yager Nicole , Nwosu Lilian N. , Pratt Arthur G. , Lara Alicia Lledo , Guzzo Charlotte , Maroof Ash , Mamanova Lira , Cole Suzanne , Efremova Mirjana , Simone Davide , Filer Andrew , Brown Chrysothemis C. , Croxford Andrew L. , Isaacs John D. , Teichmann Sarah , Bowness Paul , Behjati Sam , Hussein Al-Mossawi M. 
Published: September 2020

AbstractPsoriatic arthritis (PsA) is a debilitating immune-mediated inflammatory arthritis of unknown pathogenesis commonly affecting patients with skin psoriasis. Here we use complementary single-cell approaches to study leukocytes from PsA joints. Mass cytometry demonstrates a 3-fold expansion of memory CD8 T cells in the joints of PsA patients compared to peripheral blood. Meanwhile, droplet-based and plate-based single-cell RNA sequencing of paired T cell receptor alpha and beta chain sequences show pronounced CD8 T cell clonal expansions within the joints. Transcriptome analyses find these expanded synovial CD8 T cells to express cycling, activation, tissue-homing and tissue residency markers. T cell receptor sequence comparison between patients identifies clonal convergence. Finally, chemokine receptor CXCR3 is upregulated in the expanded synovial CD8 T cells, while two CXCR3 ligands, CXCL9 and CXCL10, are elevated in PsA synovial fluid. Our data thus provide a quantitative molecular insight into the cellular immune landscape of psoriatic arthritis.
Near-atomic resolution structures of interdigitated nucleosome fibres
Authors: Adhireksan Zenita , Sharma Deepti , Lee Phoi Leng , Davey Curt A. 
Published: September 2020

AbstractChromosome structure at the multi-nucleosomal level has remained ambiguous in spite of its central role in epigenetic regulation and genome dynamics. Recent investigations of chromatin architecture portray diverse modes of interaction within and between nucleosome chains, but how this is realized at the atomic level is unclear. Here we present near-atomic resolution crystal structures of nucleosome fibres that assemble from cohesive-ended dinucleosomes with and without linker histone. As opposed to adopting folded helical ‘30 nm’ structures, the fibres instead assume open zigzag conformations that are interdigitated with one another. Zigzag conformations obviate extreme bending of the linker DNA, while linker DNA size (nucleosome repeat length) dictates fibre configuration and thus fibre–fibre packing, which is supported by variable linker histone binding. This suggests that nucleosome chains have a predisposition to interdigitate with specific characteristics under condensing conditions, which rationalizes observations of local chromosome architecture and the general heterogeneity of chromatin structure.
Low-noise GaAs quantum dots for quantum photonics
Authors: Zhai Liang , Löbl Matthias C. , Nguyen Giang N. , Ritzmann Julian , Javadi Alisa , Spinnler Clemens , Wieck Andreas D. , Ludwig Arne , Warburton Richard J. 
Published: September 2020

AbstractQuantum dots are both excellent single-photon sources and hosts for single spins. This combination enables the deterministic generation of Raman-photons—bandwidth-matched to an atomic quantum-memory—and the generation of photon cluster states, a resource in quantum communication and measurement-based quantum computing. GaAs quantum dots in AlGaAs can be matched in frequency to a rubidium-based photon memory, and have potentially improved electron spin coherence compared to the widely used InGaAs quantum dots. However, their charge stability and optical linewidths are typically much worse than for their InGaAs counterparts. Here, we embed GaAs quantum dots into an n-i-p-diode specially designed for low-temperature operation. We demonstrate ultra-low noise behaviour: charge control via Coulomb blockade, close-to lifetime-limited linewidths, and no blinking. We observe high-fidelity optical electron-spin initialisation and long electron-spin lifetimes for these quantum dots. Our work establishes a materials platform for low-noise quantum photonics close to the red part of the spectrum.
COVID-19 image classification using deep features and fractional-order marine predators algorithm
Authors: Sahlol Ahmed T. , Yousri Dalia , Ewees Ahmed A. , Al-qaness Mohammed A. A. , Damasevicius Robertas , Elaziz Mohamed Abd 
Published: September 2020

AbstractCurrently, we witness the severe spread of the pandemic of the new Corona virus, COVID-19, which causes dangerous symptoms to humans and animals, its complications may lead to death. Although convolutional neural networks (CNNs) is considered the current state-of-the-art image classification technique, it needs massive computational cost for deployment and training. In this paper, we propose an improved hybrid classification approach for COVID-19 images by combining the strengths of CNNs (using a powerful architecture called Inception) to extract features and a swarm-based feature selection algorithm (Marine Predators Algorithm) to select the most relevant features. A combination of fractional-order and marine predators algorithm (FO-MPA) is considered an integration among a robust tool in mathematics named fractional-order calculus (FO). The proposed approach was evaluated on two public COVID-19 X-ray datasets which achieves both high performance and reduction of computational complexity. The two datasets consist of X-ray COVID-19 images by international Cardiothoracic radiologist, researchers and others published on Kaggle. The proposed approach selected successfully 130 and 86 out of 51 K features extracted by inception from dataset 1 and dataset 2, while improving classification accuracy at the same time. The results are the best achieved on these datasets when compared to a set of recent feature selection algorithms. By achieving 98.7%, 98.2% and 99.6%, 99% of classification accuracy and F-Score for dataset 1 and dataset 2, respectively, the proposed approach outperforms several CNNs and all recent works on COVID-19 images.
Enhancement of photovoltage by electronic structure evolution in multiferroic Mn-doped BiFeO3 thin films
Authors: Nakashima Seiji , Higuchi Tohru , Yasui Akira , Kinoshita Toyohiko , Shimizu Masaru , Fujisawa Hironori 
Published: September 2020

AbstractThe bulk photovoltaic effect (BPVE) is a mechanism of recent focus for novel solar cells that exceed the power conversion efficiency of p–n junction solar cells because of the quantum mechanical effect to generate photocurrent known as shift current. Ferroelectrics are receiving attention again because of their high voltage generation by the BPVE and converse piezoelectric effect to realize high performance optical actuators. We have investigated the BPVE in ferroelectric BiFeO3(BFO) single crystal thin films, whereby the photovoltage was enhanced by Mn doping, and 852 V generation was demonstrated at 80 K. The enhancement mechanism was also investigated using soft and hard X-ray photoelectron spectroscopy (SXPES, HAXPES), and soft X-ray absorption spectroscopy with synchrotron radiation. This report reveals a way to new voltage source applications employing the BPVE for high impedance devices with ferroelectrics. Important aspects for designing ferroelectric materials by impurity doping are also discussed.
Design and experimental analysis of dual-band polarization converting metasurface for microwave applications
Authors: Khan Bilawal , Kamal Babar , Ullah Sadiq , Khan Imran , Shah Jawad Ali , Chen Jingdong 
Published: September 2020

AbstractThe manipulation of polarization state of electromagnetic waves is of great importance in many practical applications. In this paper, the reflection characteristics of a thin and dual-band metasurface are examined in the microwave frequency regime. The metasurface consists of a 22 × 22 element array of periodic unit cells. The geometry of the unit cell consists of three layers, including a 45° inclined dipole shape metal patch on top, which is backed by a 1.6 mm thick FR-4 substrate in the middle, and a fully reflective metallic mirror at the bottom. The proposed surface is exposed to horizontally (x) or vertically (y) polarized plane waves and the co and cross polarization reflection coefficients of the reflected waves are investigated experimentally in the 6–26 GHz frequency range. The metasurface is designed to convert incident waves of known polarization state (horizontal or vertical) to orthogonal polarization state (vertical and horizontal) in two distinct frequency bands, i.e. 7.1–8 GHz and 13.3–25.8 GHz. In these two frequency bands the simulated and experimental results are in good agreement. The polarization conversion ratio (PCR) of the surface is greater than 95% in the targeted frequency bands. A detailed parametric analysis of the metasurface is also discussed in this work and it has been estimated that the surface has the additional ability to convert linearly polarized waves to circularly polarized waves at several distinct frequencies. The proposed metasurface can be utilized in sensor applications, stealth technology, electromagnetic measurements, and antennas design.
The combined effect of obesity and aging on human sperm DNA methylation signatures: inclusion of BMI in the paternal germ line age prediction model
Authors: Salas-Huetos Albert , James Emma R. , Broberg Dallin S. , Aston Kenneth I. , Carrell Douglas T. , Jenkins Timothy G. 
Published: September 2020

AbstractMale aging and obesity have both been shown to contribute to declines in fertility in men. Recent work in aging has shown consistent epigenetic changes to sperm as a man ages. In fact, our lab has built a tool that utilizes DNA methylation signatures from sperm to effectively predict an individual’s age. Herein, we performed this preliminary cohort study to determine if increased BMI accelerates the epigenetic aging in sperm. A total of 96 participants were divided into four age groups (22–24, 30, 40–41, and > 48 years of age) and additionally parsed into two BMI sub-categories (normal and high/obese). We found no statistically significant epigenetic age acceleration. However, it is important to note that within each age category, high BMI individuals were predicted to be older on average than their actual age (~ 1.4 years), which was not observed in the normal BMI group. To further investigate this, we re-trained a model using only the present data with and without BMI as a feature. We found a modest but non-significant improvement in prediction with BMI [r2 = 0.8814, mean absolute error (MAE) = 3.2913] compared to prediction without BMI (r2 = 0.8739, MAE = 3.3567). Future studies with higher numbers of age-matched individuals are needed to definitively understand the impact of BMI on epigenetic aging in sperm.
Initiation of reticular and spider veins, incompetent perforantes and varicose veins in the saphenous vein network of the rat
Authors: Patai Bernadett Bettina , Dornyei Gabriella , Tokes Anna-Maria , Hetthessy Judit Reka , Fees Alexander , Nadasy Gyorgy L. 
Published: September 2020

AbstractIn an attempt to induce experimental varicosity, reverse perforant vein development was initiated in the rat leg by applying a chronic (14 and 32 weeks) partial stricture on the main branch of the deep femoral vein. At surfacing of the incompetent perforantes, typical reticular vein plaques and spider veins were identified by video-microscopy and quantitative histology. Deep vein blood was channeled by them into the saphenous vein system, the extra flow deforming these vessels, causing local dilations and broken course, even undulations of larger branches.
Active meta polarizer for terahertz frequencies
Authors: Wong Hang , Wang Kai Xu , Huitema Laure , Crunteanu Aurelian 
Published: September 2020

AbstractActive meta polarizers based on phase-change materials have recently led to emerging developments in terahertz devices and systems for imaging, security, and high-speed communications. Existing technologies of adaptive control of meta polarizers are limited to the complexity of external stimuli. Here, we introduce an active terahertz polarizer consisting of a single layer of large array patterns of vanadium dioxide material integrated with metallic patch matrix to dynamically reconfigure the polarization of the terahertz waves. The proposed active polarizer is simple in structure and can independently manipulate the polarization of the incident THz waves in two orthogonal directions. In addition, the device can also be performing as a highly efficient reflector at the same frequencies. We demonstrate that efficient and fast polarization changes of THz waves can be achieved over a wide operating bandwidth. Compared with other active polarizers using mechanical, optical and thermal controls, it can be conveniently manipulated with DC bias without any external actuators, intense laser source or heater. Therefore, with the advantages of high efficiency, compact size, low loss, low cost and fast response, the proposed polarizer can be highly integrative and practical to operate within adaptive terahertz circuits and systems.
The use of light spectrum blocking films to reduce populations of Drosophila suzukii Matsumura in fruit crops
Authors: Fountain Michelle T. , Badiee Amir , Hemer Sebastian , Delgado Alvaro , Mangan Michael , Dowding Colin , Davis Frederick , Pearson Simon 
Published: September 2020

AbstractSpotted wing drosophila, Drosophila suzukii, is a serious invasive pest impacting the production of multiple fruit crops, including soft and stone fruits such as strawberries, raspberries and cherries. Effective control is challenging and reliant on integrated pest management which includes the use of an ever decreasing number of approved insecticides. New means to reduce the impact of this pest that can be integrated into control strategies are urgently required. In many production regions, including the UK, soft fruit are typically grown inside tunnels clad with polyethylene based materials. These can be modified to filter specific wavebands of light. We investigated whether targeted spectral modifications to cladding materials that disrupt insect vision could reduce the incidence of D. suzukii. We present a novel approach that starts from a neuroscientific investigation of insect sensory systems and ends with infield testing of new cladding materials inspired by the biological data. We show D. suzukii are predominantly sensitive to wavelengths below 405 nm (ultraviolet) and above 565 nm (orange & red) and that targeted blocking of lower wavebands (up to 430 nm) using light restricting materials reduces pest populations up to 73% in field trials.