bluuebunny/crossref_metadata_2025 huggingface dataset:
The Inconsistent Pairs Between In Situ Observations of Near Surface Salinity and Multiple Remotely Sensed Salinity Data
Authors: Yan Hengqian , Wang Huizan , Zhang Ren , Bao Senliang , Chen Jian , Wang Gongjie
Published: April 2021

This study employs three remotely sensed Sea Surface Salinity products to diagnose the “inconsistent pairs” between the in situ observations of the Near Surface Salinity from delayed‐mode tropical moored buoys and Argo floats and the satellite salinity in the temporal range of April 2015–December 2018. By means of an adapted 3‐Sigma criterion and unanimous voting strategy, 11 (636) moored buoys (Argo floats) have at least one inconsistent observation pairs in their time series and 1 (41) have more than five. Besides, the time series of 1 (25) moored buoy (Argo floats) is diagnosed as inconsistent series due to the large bias of the whole series. Corresponding to a wide range of shifted observations, the continuous inconsistent values of moored buoy 8n38w can be flagged as bad observations. In terms of Argo, the combined analysis of time series, trajectories, profiles, and analyzed fields implies that the inconsistent pairs between Argo and satellite products are closely related to the mesoscale motions. The results suggest that sub‐footprint variability plays a dominant role in the inconsistent pairs of Argo, as most inconsistencies are characterized by the near‐surface mixed layer. Furthermore, the continuous positive inconsistencies of Argo 4901466 highlight the temporal under‐sampling of the existing satellite salinity products.
Identification of Electron Diffusion Regions with a Machine Learning Approach on MMS Data at the Earth's Magnetopause
Authors: Lenouvel Q. , Génot V. , Garnier P. , Toledo‐Redondo S. , Lavraud B. , Aunai N. , Nguyen G. , Gershman D. J. , Ergun R. E. , Lindqvist P.‐A. , Giles B. , Burch J. L.
Published: April 2021

This article presents 18 magnetic reconnection electron diffusion region (EDR) candidates found using a neural network algorithm with the Magnetospheric Multiscale Mission phase 1a data at the Earth's dayside magnetopause. These new candidates are compared to the 32 previously reported dayside EDRs listed in Webster et al. (2018), https://doi.org/10.1029/2018ja025245, which constitute the training database of our algorithm. One of the main parameters used is a scalar quantity called “MeanRL” which is based on the asymmetry of the electron velocity distribution function and better identifies electron agyrotropy in the plane perpendicular to the magnetic field. In the light of the new EDR candidates found, we discuss and analyze the sign of the energy dissipation during the reconnection process and the distinction between the inner and outer EDRs, with 40% of the candidates showing negative or oscillating dissipation. We also present in details one of the new identified EDR candidates.
Early Stage and Main Ruptures of the 2015 Mw8.3 Illapel, Chile, Megathrust Earthquake: Kinematic Elliptical Inversions and Dynamic Rupture Simulations
Authors: Aochi Hideo , Ruiz Sergio
Published: April 2021

We apply kinematic and dynamic modeling to the 2015 Mw8.3 Illapel, Chile, earthquake constrained by continuous high‐rate GPS and strong motion data. Kinematic inversion by elliptical patches allows us to rapidly outline the ruptured area with different time windows and frequency ranges. The preferred solution indicates that the main large patch in the north is preceded by a small one in the south close to the hypocenter with a time shift no greater than 20 s. The rupture directivity on the main patch suggests that the origin is at depth, away from the initial small hypocentral patch. We then construct dynamic rupture models to be consistent with the geometry obtained from the kinematic inversion. We estimate the fracture energy of the main patch to be ∼7.5 MJ/m2. The initial rupture of the small hypocentral patch does not trigger the main patch due to the gap in fracture energy, and thus another nucleation is set at depth. This can be regarded as a foreshock‐mainshock sequence rather than a direct cascade rupture growth. The ruptured area corresponds to the preexisting zone of large interseismic coupling prior to the Illapel earthquake. The historical seismicity of the previous century suggests a possible reconstruction of the asperity map, assuming that every earthquake represents a characteristic seismogenic patch. Therefore, the construction of dynamic ruptures with geodetic and seismological knowledge is possible and useful not only for reproducing known earthquakes but also for providing a physically constrained model for quantitative seismic hazard study.
Competition Among Limestone Depressions Leads to Self‐Organized Regular Patterning on a Flat Landscape
Authors: Dong Xiaoli , Murray A. Brad , Heffernan James B.
Published: April 2021

Self‐organized pattern formation is widespread and functionally significant. Scale‐dependent feedback in space (short‐distance positive feedback coupled with long‐distance negative feedback) has been embraced as an arguably universal mechanism of ecological self‐organization. Recently, intraspecific territorial competition has been proposed as a complementary mechanism contributing to spatial self‐organization in ecology. In geomorphology, regular patterning is also widespread and has often been attributed to competition among geomorphic features. This mechanism has never been integrated into the framework of ecological pattern formation. Using the regularly patterned landscape of Big Cypress National Preserve in South Florida as a case study, we formalize a third mechanism of spatial self‐organization: competition among pattern elements of finite amplitude stabilized by scale‐dependent feedback in time. Depressions first accelerate their expansion rate via the positive feedback between depression volume and weathering rate. Later negative feedbacks become stronger, and eventually stabilize the size of depressions. While scale‐dependent feedback in time provides a mechanism to stabilize individual depressions, it is the competition among depressions that induces spatial regularity. A relatively smaller depression could have a greater expansion rate than larger ones in its development. Higher weathering rate on the side of a divide toward the smaller depression causes migration of the divide to the larger depression. Consequently, the smaller depression expands its catchment area while the catchment area of the neighboring larger depression contracts, resulting in depressions achieving similar size and distance from each other. The diversity of regular patterns dictates the need to integrate perspectives from multiple disciplines.
Habitual coffee drinkers display a distinct pattern of brain functional connectivity
Authors: Magalhães Ricardo , Picó-Pérez Maria , Esteves Madalena , Vieira Rita , Castanho Teresa C. , Amorim Liliana , Sousa Mafalda , Coelho Ana , Fernandes Henrique M. , Cabral Joana , Moreira Pedro S. , Sousa Nuno
Published: April 2021

Coffee is the most widely consumed source of caffeine worldwide, partly due to the psychoactive effects of this methylxanthine. Interestingly, the effects of its chronic consumption on the brain’s intrinsic functional networks are still largely unknown. This study provides the first extended characterization of the effects of chronic coffee consumption on human brain networks. Subjects were recruited and divided into two groups: habitual coffee drinkers (CD) and non-coffee drinkers (NCD). Resting-state functional magnetic resonance imaging (fMRI) was acquired in these volunteers who were also assessed regarding stress, anxiety, and depression scores. In the neuroimaging evaluation, the CD group showed decreased functional connectivity in the somatosensory and limbic networks during resting state as assessed with independent component analysis. The CD group also showed decreased functional connectivity in a network comprising subcortical and posterior brain regions associated with somatosensory, motor, and emotional processing as assessed with network-based statistics; moreover, CD displayed longer lifetime of a functional network involving subcortical regions, the visual network and the cerebellum. Importantly, all these differences were dependent on the frequency of caffeine consumption, and were reproduced after NCD drank coffee. CD showed higher stress levels than NCD, and although no other group effects were observed in this psychological assessment, increased frequency of caffeine consumption was also associated with increased anxiety in males. In conclusion, higher consumption of coffee and caffeinated products has an impact in brain functional connectivity at rest with implications in emotionality, alertness, and readiness to action.
Decreased DNA methylation at promoters and gene-specific neuronal hypermethylation in the prefrontal cortex of patients with bipolar disorder
Authors: Bundo Miki , Ueda Junko , Nakachi Yutaka , Kasai Kiyoto , Kato Tadafumi , Iwamoto Kazuya
Published: April 2021

Bipolar disorder (BD) is a severe mental disorder characterized by repeated mood swings. Although genetic factors are collectively associated with the etiology of BD, the underlying molecular mechanisms, particularly how environmental factors affect the brain, remain largely unknown. We performed promoter-wide DNA methylation analysis of neuronal and nonneuronal nuclei in the prefrontal cortex of patients with BD (N = 34) and controls (N = 35). We found decreased DNA methylation at promoters in both cell types in the BD patients. Gene Ontology (GO) analysis of differentially methylated region (DMR)-associated genes revealed enrichment of molecular motor-related genes in neurons, chemokines in both cell types, and ion channel- and transporter-related genes in nonneurons. Detailed GO analysis further revealed that growth cone- and dendrite-related genes, including NTRK2 and GRIN1, were hypermethylated in neurons of BD patients. To assess the effect of medication, neuroblastoma cells were cultured under therapeutic concentrations of three mood stabilizers. We observed that up to 37.9% of DMRs detected in BD overlapped with mood stabilizer-induced DMRs. Interestingly, mood stabilizer-induced DMRs showed the opposite direction of changes in DMRs, suggesting the therapeutic effects of mood stabilizers. Among the DMRs, 12 overlapped with loci identified in a genome-wide association study (GWAS) of BD. We also found significant enrichment of neuronal DMRs in the loci reported in another GWAS of BD. Finally, we performed qPCR of DNA methylation-related genes and found that DNMT3B was overexpressed in BD. The cell-type-specific DMRs identified in this study will be useful for understanding the pathophysiology of BD.
FOXO3a protects glioma cells against temozolomide-induced DNA double strand breaks via promotion of BNIP3-mediated mitophagy
Authors: He Chuan , Lu Shan , Wang Xuan-zhong , Wang Chong-cheng , Wang Lei , Liang Shi-peng , Luo Tian-fei , Wang Zhen-chuan , Piao Mei-hua , Chi Guang-fan , Ge Peng-fei
Published: April 2021

FOXO3a (forkhead box transcription factor 3a) is involved in regulating multiple biological processes in cancer cells. BNIP3 (Bcl-2/adenovirus E1B 19-kDa-interacting protein 3) is a receptor accounting for priming damaged mitochondria for autophagic removal. In this study we investigated the role of FOXO3a in regulating the sensitivity of glioma cells to temozolomide (TMZ) and its relationship with BNIP3-mediated mitophagy. We showed that TMZ dosage-dependently inhibited the viability of human U87, U251, T98G, LN18 and rat C6 glioma cells with IC50 values of 135.75, 128.26, 142.65, 155.73 and 111.60 μM, respectively. In U87 and U251 cells, TMZ (200 μM) induced DNA double strand breaks (DSBs) and nuclear translocation of apoptosis inducing factor (AIF), which was accompanied by BNIP3-mediated mitophagy and FOXO3a accumulation in nucleus. TMZ treatment induced intracellular ROS accumulation in U87 and U251 cells via enhancing mitochondrial superoxide, which not only contributed to DNA DSBs and exacerbated mitochondrial dysfunction, but also upregulated FOXO3a expression. Knockdown of FOXO3a aggravated TMZ-induced DNA DSBs and mitochondrial damage, as well as glioma cell death. TMZ treatment not only upregulated BNIP3 and activated autophagy, but also triggered mitophagy by prompting BNIP3 translocation to mitochondria and reinforcing BNIP3 interaction with LC3BII. Inhibition of mitophagy by knocking down BNIP3 with SiRNA or blocking autophagy with 3MA or bafilomycin A1 exacerbated mitochondrial superoxide and intracellular ROS accumulation. Moreover, FOXO3a knockdown inhibited TMZ-induced BNIP3 upregulation and autophagy activation. In addition, we showed that treatment with TMZ (100 mg·kg−1·d−1, ip) for 12 days in C6 cell xenograft mice markedly inhibited tumor growth accompanied by inducing FOXO3a upregulation, oxidative stress and BNIP3-mediated mitophagy in tumor tissues. These results demonstrate that FOXO3a attenuates temozolomide-induced DNA double strand breaks in human glioma cells via promoting BNIP3-mediated mitophagy.
Loss of α2-6 sialylation promotes the transformation of synovial fibroblasts into a pro-inflammatory phenotype in arthritis
Authors: Wang Yilin , Khan Aneesah , Antonopoulos Aristotelis , Bouché Laura , Buckley Christopher D. , Filer Andrew , Raza Karim , Li Kun-Ping , Tolusso Barbara , Gremese Elisa , Kurowska-Stolarska Mariola , Alivernini Stefano , Dell Anne , Haslam Stuart M. , Pineda Miguel A.
Published: April 2021

In healthy joints, synovial fibroblasts (SFs) provide the microenvironment required to mediate homeostasis, but these cells adopt a pathological function in rheumatoid arthritis (RA). Carbohydrates (glycans) on cell surfaces are fundamental regulators of the interactions between stromal and immune cells, but little is known about the role of the SF glycome in joint inflammation. Here we study stromal guided pathophysiology by mapping SFs glycosylation pathways. Combining transcriptomic and glycomic analysis, we show that transformation of fibroblasts into pro-inflammatory cells is associated with glycan remodeling, a process that involves TNF-dependent inhibition of the glycosyltransferase ST6Gal1 and α2-6 sialylation. SF sialylation correlates with distinct functional subsets in murine experimental arthritis and remission stages in human RA. We propose that pro-inflammatory cytokines remodel the SF-glycome, converting the synovium into an under-sialylated and highly pro-inflammatory microenvironment. These results highlight the importance of glycosylation in stromal immunology and joint inflammation.
Prostaglandin in the ventromedial hypothalamus regulates peripheral glucose metabolism
Authors: Lee Ming-Liang , Matsunaga Hirokazu , Sugiura Yuki , Hayasaka Takahiro , Yamamoto Izumi , Ishimoto Taiga , Imoto Daigo , Suematsu Makoto , Iijima Norifumi , Kimura Kazuhiro , Diano Sabrina , Toda Chitoku
Published: April 2021

The hypothalamus plays a central role in monitoring and regulating systemic glucose metabolism. The brain is enriched with phospholipids containing poly-unsaturated fatty acids, which are biologically active in physiological regulation. Here, we show that intraperitoneal glucose injection induces changes in hypothalamic distribution and amounts of phospholipids, especially arachidonic-acid-containing phospholipids, that are then metabolized to produce prostaglandins. Knockdown of cytosolic phospholipase A2 (cPLA2), a key enzyme for generating arachidonic acid from phospholipids, in the hypothalamic ventromedial nucleus (VMH), lowers insulin sensitivity in muscles during regular chow diet (RCD) feeding. Conversely, the down-regulation of glucose metabolism by high fat diet (HFD) feeding is improved by knockdown of cPLA2 in the VMH through changing hepatic insulin sensitivity and hypothalamic inflammation. Our data suggest that cPLA2-mediated hypothalamic phospholipid metabolism is critical for controlling systemic glucose metabolism during RCD, while continuous activation of the same pathway to produce prostaglandins during HFD deteriorates glucose metabolism.
SMART transfer method to directly compare the mechanical response of water-supported and free-standing ultrathin polymeric films
Authors: Galuska Luke A. , Muckley Eric S. , Cao Zhiqiang , Ehlenberg Dakota F. , Qian Zhiyuan , Zhang Song , Rondeau-Gagné Simon , Phan Minh D. , Ankner John F. , Ivanov Ilia N. , Gu Xiaodan
Published: April 2021

Intrinsic mechanical properties of sub-100 nm thin films are markedly difficult to obtain, yet an ever-growing necessity for emerging fields such as soft organic electronics. To complicate matters, the interfacial contribution plays a major role in such thin films and is often unexplored despite supporting substrates being a main component in current metrologies. Here we present the shear motion assisted robust transfer technique for fabricating free-standing sub-100 nm films and measuring their inherent structural–mechanical properties. We compare these results to water-supported measurements, exploring two phenomena: 1) The influence of confinement on mechanics and 2) the role of water on the mechanical properties of hydrophobic films. Upon confinement, polystyrene films exhibit increased strain at failure, and reduced yield stress, while modulus is reduced only for the thinnest 19 nm film. Water measurements demonstrate subtle differences in mechanics which we elucidate using quartz crystal microbalance and neutron reflectometry.
Higher-order and fractional discrete time crystals in clean long-range interacting systems
Authors: Pizzi Andrea , Knolle Johannes , Nunnenkamp Andreas
Published: April 2021

Discrete time crystals are periodically driven systems characterized by a response with periodicity nT, with T the period of the drive and n > 1. Typically, n is an integer and bounded from above by the dimension of the local (or single particle) Hilbert space, the most prominent example being spin-1/2 systems with n restricted to 2. Here, we show that a clean spin-1/2 system in the presence of long-range interactions and transverse field can sustain a huge variety of different ‘higher-order’ discrete time crystals with integer and, surprisingly, even fractional n > 2. We characterize these (arguably prethermal) non-equilibrium phases of matter thoroughly using a combination of exact diagonalization, semiclassical methods, and spin-wave approximations, which enable us to establish their stability in the presence of competing long- and short-range interactions. Remarkably, these phases emerge in a model with continous driving and time-independent interactions, convenient for experimental implementations with ultracold atoms or trapped ions.
Unexpected organic hydrate luminogens in the solid state
Authors: Zhou Feng , Gu Peiyang , Luo Zhipu , Bisoyi Hari Krishna , Ji Yujin , Li Youyong , Xu Qingfeng , Li Quan , Lu Jianmei
Published: April 2021

Developing organic photoluminescent materials with high emission efficiencies in the solid state under a water atmosphere is important for practical applications. Herein, we report the formation of both intra- and intermolecular hydrogen bonds in three tautomerizable Schiff-base molecules which comprise active hydrogen atoms that act as proton donors and acceptors, simultaneously hindering emission properties. The intercalation of water molecules into their crystal lattices leads to structural rearrangement and organic hydrate luminogen formation in the crystalline phase, triggering significantly enhanced fluorescence emission. By suppressing hydrogen atom shuttling between two nitrogen atoms in the benzimidazole ring, water molecules act as hydrogen bond donors to alter the electronic transition of the molecular keto form from nπ* to lower-energy ππ* in the excited state, leading to enhancing emission from the keto form. Furthermore, the keto-state emission can be enhanced using deuterium oxide (D2O) owing to isotope effects, providing a new opportunity for detecting and quantifying D2O.
Seasonal dynamics of diet–gut microbiota interaction in adaptation of yaks to life at high altitude
Authors: Guo Na , Wu Qunfu , Shi Fuyu , Niu Jiahuan , Zhang Tao , Degen A. Allan , Fang Qiangen , Ding Luming , Shang Zhanhuan , Zhang Zhigang , Long Ruijun
Published: April 2021

Dietary selection and intake affect the survival and health of mammals under extreme environmental conditions. It has been suggested that dietary composition is a key driver of gut microbiota variation; however, how gut microbiota respond to seasonal dietary changes under extreme natural conditions remains poorly understood. Sequencing plant trnL (UAA) region and 16S rRNA gene analysis were employed to determine dietary composition and gut microbiota in freely grazing yaks on the Tibetan plateau. Dietary composition was more diverse in winter than in summer, while Gramineae and Rosaceae were consumed frequently all year. Turnover of seasonal diet and gut microbiota composition occurred consistently. Yaks shifted enterotypes in response to dietary change between warm and cold seasons to best utilize nitrogen and energy, in particular in the harsh cold season. Our findings provide insights into understanding seasonal changes of diet–microbiota linkages in the adaptation of mammals to high altitudes.
Two-step machine learning enables optimized nanoparticle synthesis
Authors: Mekki-Berrada Flore , Ren Zekun , Huang Tan , Wong Wai Kuan , Zheng Fang , Xie Jiaxun , Tian Isaac Parker Siyu , Jayavelu Senthilnath , Mahfoud Zackaria , Bash Daniil , Hippalgaonkar Kedar , Khan Saif , Buonassisi Tonio , Li Qianxiao , Wang Xiaonan
Published: April 2021

In materials science, the discovery of recipes that yield nanomaterials with defined optical properties is costly and time-consuming. In this study, we present a two-step framework for a machine learning-driven high-throughput microfluidic platform to rapidly produce silver nanoparticles with the desired absorbance spectrum. Combining a Gaussian process-based Bayesian optimization (BO) with a deep neural network (DNN), the algorithmic framework is able to converge towards the target spectrum after sampling 120 conditions. Once the dataset is large enough to train the DNN with sufficient accuracy in the region of the target spectrum, the DNN is used to predict the colour palette accessible with the reaction synthesis. While remaining interpretable by humans, the proposed framework efficiently optimizes the nanomaterial synthesis and can extract fundamental knowledge of the relationship between chemical composition and optical properties, such as the role of each reactant on the shape and amplitude of the absorbance spectrum.
The prevalence and outcome of short-acting β2-agonists overuse in asthma patients in Taiwan
Authors: Wang Cheng-Yi , Lai Chih-Cheng , Wang Ya-Hui , Wang Hao-Chien
Published: April 2021

This study aims to investigate the prevalence of short-acting β2-agonist (SABA) overuse in asthma and the associated risk of acute exacerbation and mortality in Taiwan. We used the Taiwanese pay-for-performance asthma program database, which included patients aged between 12 and 100 years who were enrolled in the program between 2001 and 2015. Among a total of 218,039 patients, 34,641 (15.9%) patients are classified as SABA over-users. Compared with patients who did not receive inhaled corticosteroids (ICS) and collected ≤2 canisters, SABA over-users had a higher risk of severe exacerbations. SABA over-users had a higher risk of all-cause mortality compared with patients who did not receive ICS and collected ≤2 canisters. The overall prevalence of SABA overuse in Taiwan is 15.9%, and this is even higher in concomitant ICS users. In addition, the overuse of SABA is associated with an increased risk of severe exacerbation and death.
Low-rank density-matrix evolution for noisy quantum circuits
Authors: Chen Yi-Ting , Farquhar Collin , Parrish Robert M.
Published: April 2021

In this work, we present an efficient rank-compression approach for the classical simulation of Kraus decoherence channels in noisy quantum circuits. The approximation is achieved through iterative compression of the density matrix based on its leading eigenbasis during each simulation step without the need to store, manipulate, or diagonalize the full matrix. We implement this algorithm using an in-house simulator and show that the low-rank algorithm speeds up simulations by more than two orders of magnitude over existing implementations of full-rank simulators, and with negligible error in the noise effect and final observables. Finally, we demonstrate the utility of the low-rank method as applied to representative problems of interest by using the algorithm to speed up noisy simulations of Grover’s search algorithm and quantum chemistry solvers.
Author Correction: The influence of human genetic variation on Epstein–Barr virus sequence diversity
Authors: Rüeger Sina , Hammer Christian , Loetscher Alexis , McLaren Paul J. , Lawless Dylan , Naret Olivier , Khanna Nina , Bernasconi Enos , Cavassini Matthias , Günthard Huldrych F. , Kahlert Christian R. , Rauch Andri , Depledge Daniel P. , Morfopoulou Sofia , Breuer Judith , Zdobnov Evgeny , Fellay Jacques ,   the Swiss HIV Cohort Study, Aebi-Popp Karoline , Anagnostopoulos Alexia , Battegay Manuel , Bernasconi Enos , Böni Jürg , Braun Dominique , Bucher Heiner , Calmy Alexandra , Cavassini Matthias , Ciuffi Angela , Dollenmaier Guenter , Egger Matthias , Elzi Luigia , Fehr Jan , Fellay Jacques , Furrer Hansjakob , Fux Christoph , Günthard Huldrych F. , Haerry David , Hasse Barbara , Hirsch Hans , Hoffmann Matthias , Hösli Irene , Huber Michael , Kahlert Christian R. , Kaiser Laurent , Keiser Olivia , Klimkait Thomas , Kottanattu Lisa , Kouyos Roger , Kovari Helen , Ledergerber Bruno , Martinetti Gladys , de Tejada Begoña Martinez , Marzolini Catia , Metzner Karin , Müller Nicolas , Nicca Dunja , Paioni Paolo , Pantaleo Giuseppe , Perreau Matthieu , Rauch Andri , Rudin Christoph , Scherrer Alexandra , Schmid Patrick , Speck Roberto , Stöckle Marcel , Tarr Philip , Trkola Alexandra , Vernazza Pietro , Wagner Noémie , Wandeler Gilles , Weber Rainer , Yerly Sabine
Published: April 2021

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Relationship between retinal capillary vessel density of OCT angiography and intraocular pressure in pig
Authors: Choi Mihyun , Kim Seong-Woo , Ahn Somin , Vu Thi Que Anh , Yun Cheolmin , Kim Yong Yeon
Published: April 2021

The purpose of this study was to evaluate density change in the retinal capillary plexus during intra ocular pressure (IOP) elevation in vitrectomized pigs’ eyes using optical coherence tomography angiography (OCTA). Eight eyes of eight micro pigs received vitrectomy and the IOP was controlled from 15 mmHg (baseline) to 105 mmHg in 15 mmHg increments using a vented-gas forced-infusion system, and then decreased back to normal IOP (recovery state). The spectral-domain OCTA device was set to scan an area of 8.8 × 4.4 mm (30° × 15°) above the optic nerve head for each IOP. The relative vessel density (rVAD) compared to baseline was determined for the total retinal blood flow (RBF) which included major retinal artery and venous vessels, radial peripapillary capillaries (RPCs), superficial (SVP), intermediate (IVP), and deep vascular plexus (DVP). The mean rVAD was 0.890 in RBF, 0.826 in RPCs, 0.817 in SVP, 0.819 in IVP, and 0.794 in DVP at 30 mmHg. While the rVAD of RBF and RPCs decreased to 0.504 and 0.541 at 45 mmHg, the SVP, IVP, and DVP decreased to 0.433, 0.359, and 0.345, respectively. When IOP was normalized, the rVAD was recovered in all layers and the VAD of RBF, IVP, and DVP were higher than baseline (P = 0.040, 0.019, and 0.019, respectively). Retinal capillary density deterioration in each layer was found from 30 mmHg using an OCTA system which showed excellent depth-resolved segmentation of retinal capillary layers even at higher IOPs. Reduction in VAD showed full recovery after IOP normalization.
Author Correction: Gestational weight gain and foetal acidosis in vaginal and caesarean deliveries: The Japan Environment and Children’s Study
Authors: Murata Tsuyoshi , Kyozuka Hyo , Yamaguchi Akiko , Fukuda Toma , Yasuda Shun , Sato Akiko , Ogata Yuka , Shinoki Kosei , Hosoya Mitsuaki , Yasumura Seiji , Hashimoto Koichi , Nishigori Hidekazu , Fujimori Keiya ,   The Japan Environment, Children’s Study (JECS) Group, Kamijima Michihiro , Yamazaki Shin , Ohya Yukihiro , Kishi Reiko , Yaegashi Nobuo , Mori Chisato , Ito Shuichi , Yamagata Zentaro , Inadera Hidekuni , Nakayama Takeo , Iso Hiroyasu , Shima Masayuki , Kurozawa Youichi , Suganuma Narufumi , Kusuhara Koichi , Katoh Takahiko
Published: April 2021

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Deep learning early stopping for non-degenerate ghost imaging
Authors: Moodley Chané , Sephton Bereneice , Rodríguez-Fajardo Valeria , Forbes Andrew
Published: April 2021

Quantum ghost imaging offers many advantages over classical imaging, including the ability to probe an object with one wavelength and record the image with another (non-degenerate ghost imaging), but suffers from slow image reconstruction due to sparsity and probabilistic arrival positions of photons. Here, we propose a two-step deep learning approach to establish an optimal early stopping point based on object recognition, even for sparsely filled images. In step one we enhance the reconstructed image after every measurement by a deep convolutional auto-encoder, followed by step two in which a classifier is used to recognise the image. We test this approach on a non-degenerate ghost imaging setup while varying physical parameters such as the mask type and resolution. We achieved a fivefold decrease in image acquisition time at a recognition confidence of $$75\%$$

75
%

. The significant reduction in experimental running time is an important step towards real-time ghost imaging, as well as object recognition with few photons, e.g., in the detection of light sensitive structures.
Author Correction: Extracting backbones in weighted modular complex networks
Authors: Ghalmane Zakariya , Cherifi Chantal , Cherifi Hocine , Hassouni Mohammed El
Published: April 2021

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
In silico exploration of lignin peroxidase for unraveling the degradation mechanism employing lignin model compounds
Authors: Singh Anil Kumar , Katari Sudheer Kumar , Umamaheswari Amineni , Raj Abhay
Published: April 2021

The findings herein demonstrate that bacterial LiP can effectively catalyze multiple lignin model compounds, and it might further be used as an effective tool for sustainable mitigation of diverse environmental contaminants.
Inductively coupled plasma optical emission spectroscopy as a tool for evaluating lateral flow assays
Authors: DeSousa Jenna M. , Jorge Micaella Z. , Lindsay Hayley B. , Haselton Frederick R. , Wright David W. , Scherr Thomas F.
Published: April 2021

This work demonstrates the first use of ICP-OES to quantitatively analyze gold content on lateral flow assays.
Homo- and hetero-metallophilicity-driven synthesis of highly emissive and stimuli-responsive Au(i)–Cu(i) double salts
Authors: Kobayashi Ryosuke , Yumura Takashi , Imoto Hiroaki , Naka Kensuke
Published: April 2021

Discrete complex salts having Au···Au and Au···Cu interactions were obtained as three crystalline polymorphs exhibiting various emission colors with high efficiency. Solvent vapor caused crystal-to-crystal transition, changing the emission color.
Pd/Ni-Catalyzed Germa-Suzuki coupling via dual Ge–F bond activation
Authors: Kameo Hajime , Mushiake Akihiro , Isasa Tomohito , Matsuzaka Hiroyuki , Bourissou Didier
Published: April 2021

Pd/Ni → Ge–F interactions supported by phosphine-chelation were found to trigger dual activation of Ge–F bonds under mild conditions.
Homochiral anionic modification toward the chemical design of organic enantiomeric ferroelectrics
Authors: Li Yibao , Du Ye , Huang Chao-Ran , Peng Hang , Zeng Yu-Ling , Liu Jun-Chao , Liao Wei-Qiang
Published: April 2021

Enantiomeric multiaxial ferroelectrics, (quinuclidinium)(l- and d-camphorsulfonate), were designed by the homochiral anionic modification of non-ferroelectric (quinuclidinium)(HSO4).
Analysis of slip systems in protein crystals with a triclinic form using a phenomenological macro-bond method
Authors: Suzuki Ryo , Shigemoto Chika , Abe Marina , Kojima Kenichi , Tachibana Masaru
Published: April 2021

Slip systems in triclinic hen egg-white lysozyme (Tri-HEWL) crystals, which is one of typical protein crystals, were identified by the indentation method and the surface energy estimation using phenomenological macro-bond methods.
Anion-dependent structural variations and charge transport property analysis of 4′-(3-pyridyl)-4,2′:6′,4′′-terpyridinium salts
Authors: Hossain Anowar , Dey Arka , Seth Saikat Kumar , Ray Partha Pratim , Ortega-Castro Joaquín , Frontera Antonio , Mukhopadhyay Subrata
Published: April 2021

Anion-dependent structural variations and charge transport analysis of three 4′-(3-pyridyl)-4,2′:6′,4′′-terpyridinium salts are reported. They exhibit pronounced photosensing behavior when illuminated using visible light.
3D Ln-MOFs as multi-responsive luminescent probes for efficient sensing of Fe3+, Cr2O72−, and antibiotics in aqueous solution
Authors: Xue Yun-Shan , Ding Ji , Sun Dan-Ling , Cheng Wei-Wei , Chen Xuan-Rong , Huang Xing-Cai , Wang Jun
Published: April 2021

Two families of Ln-based MOFs with 3D structures have been synthesized under solvothermal conditions. Eu-MOF (4) can act as a multi-responsive luminescent probe in water systems and Dy-MOF (6) shows slow magnetic relaxation behaviors.
An oral biologics carrier from modified halloysite nanotubes
Authors: Pumchan Ansaya , Cheycharoen Orrapa , Unajak Sasimanas , Prasittichai Chaiya
Published: April 2021

Herein, we report the use of surface-modified halloysite as an effective oral vaccine carrier for Nile tilapia.
Intrinsic effect of interfacial coupling on the high-frequency intralayer modes in twisted multilayer MoTe2
Authors: Leng Yu-Chen , Lin Miao-Ling , Zhou Yu , Wu Jiang-Bin , Meng Da , Cong Xin , Li Hai , Tan Ping-Heng
Published: April 2021

The out-of-plane intralayer modes in twisted multilayer MoTe2 are sensitive to its interfacial layer-breathing coupling, while the in-plane intralayer modes are localized within its constituents due to the negligible shear coupling at the interface.
Tuning the photonic properties of graphene oxide suspensions with nanostructured additives
Authors: Xu Yi-Tao , Mody Urmi Vijay , MacLachlan Mark J.
Published: April 2021

Colloidal additives such as clay nanoplates and cellulose nanocrystals induce the ordering formation of graphene oxide via depletion interaction for hybrid photonic suspensions with temperature-sensitive properties.
A new donor for charge-transfer systems: synthesis and properties of 2,4,7,9-tetramethyl-1,6-dithiapyrene (TMDTP) and structure of (TMDTP)3(PF6)2·2THF and TMDTP–TCNQ
Authors: Bendix Jesper , Bechgaard Klaus , Christensen Jørn Bolstad
Published: April 2021

The heterocyclic donor molecule 2,4,7,9-tetramethyl-1,6-dithiapyrene (TMDTP) has been synthesized in five steps. The charge-transfer complex, TMDTP–TCNQ, has been prepared and the salt, (TMDTP)3(PF6)2·2THF, obtained by electrocrystallization.
Machine learning vs. field 3D-QSAR models for serotonin 2A receptor psychoactive substances identification
Authors: Floresta Giuseppe , Abbate Vincenzo
Published: April 2021

Five QSAR models for predicting the affinity of 5-HT2AR ligands have been developed. The resulting models generate a useful tool for the investigation and identification of unclassified new psychoactive substances (NPS).
Simultaneous detection of vesicular content and exocytotic release with two electrodes in and at a single cell
Authors: Gu Chaoyi , Ewing Andrew G.
Published: April 2021

Simultaneous measurements of IVIEC and SCA by two nanotip electrodes allows direct and dynamic comparison between vesicular transmitter content and vesicular transmitter release to shed light on stimulation-induced plasticity.
Dion–Jacobson halide perovskites for photovoltaic and photodetection applications
Authors: Fu Huiying
Published: April 2021

This review focuses on recent progress involving the photovoltaic and photodetection properties of Dion–Jacobson perovskites and the enhanced stability of Dion–Jacobson perovskite solar cells.
Integrin αVβ1 regulates procollagen I production through a non-canonical transforming growth factor β signaling pathway in human hepatic stellate cells
Authors: Han Zuoning , Ma Yanling , Cao Gary , Ma Zhengping , Chen Ruihua , Cvijic Mary Ellen , Cheng Dong
Published: April 2021

Hepatic stellate cells (HSCs) are thought to play key roles in the development of liver fibrosis. Extensive evidence has established the concept that αV integrins are involved in the activation of latent transforming growth factor β (TGF-β), a master regulator of the fibrotic signaling cascade. Based on mRNA and protein expression profiling data, we found that αVβ1 integrin is the most abundant member of the αV integrin family in either quiescent or TGF-β1-activated primary human HSCs. Unexpectedly, either a selective αVβ1 inhibitor, Compound 8 (C8), or a pan-αV integrin inhibitor, GSK3008348, decreased TGF-β1-activated procollagen I production in primary human HSCs, in which the role of β1 integrin was confirmed by ITGB1 siRNA. In contrast with an Activin receptor-like kinase 5 (Alk5) inhibitor, C8 and GSK3008348 failed to inhibit TGF-β1 induced SMAD3 and SMAD2 phosphorylation, but inhibited TGF-β-induced phosphorylation of ERK1/2 and STAT3, suggesting that αVβ1 integrin is involved in non-canonical TGF-β signaling pathways. Consistently, ITGB1 siRNA significantly decreased phosphorylation of ERK1/2. Furthermore, a selective inhibitor of MEK1/2 blocked TGF-β1 induced phosphorylation of ERK1/2 and decreased TGF-β1 induced procollagen I production, while a specific inhibitor of STAT3 had no effect on TGF-β1 induced procollagen I production. Taken together, current data indicate that αVβ1 integrin can regulate TGF-β signaling independent of its reported role in activating latent TGF-β. Our data further support that αVβ1 inhibition is a promising therapeutic target for the treatment of liver fibrosis.
The eROSITA Final Equatorial-Depth Survey (eFEDS)
Authors: Toba Yoshiki , Brusa Marcella , Liu Teng , Buchner Johannes , Terashima Yuichi , Urrutia Tanya , Salvato Mara , Akiyama Masayuki , Arcodia Riccardo , Goulding Andy D. , Higuchi Yuichi , Inoue Kaiki T. , Kawaguchi Toshihiro , Lamer Georg , Merloni Andrea , Nagao Tohru , Ueda Yoshihiro , Nandra Kirpal
Published: April 2021

In this study, we investigate the X-ray properties of WISE J090924.01+000211.1 (WISEJ0909+0002), an extremely luminous infrared (IR) galaxy (ELIRG) at zspec = 1.871 in the eROSITA Final Equatorial-Depth Survey. WISEJ0909+0002 is a WISE 22 μm source, located in the GAMA-09 field, which was detected by eROSITA during the performance and verification phase. The corresponding optical spectrum indicates that this object is a type-1 active galactic nucleus (AGN). Observations from eROSITA combined with Chandra and XMM-Newton archival data indicate a very luminous (L (2–10 keV) = (2.1 ± 0.2) × 1045 erg s−1) unobscured AGN with a power-law photon index of Γ=1.73−0.15+0.16 and an absorption hydrogen column density of log (NH∕cm−2) < 21.0. The IR luminosity was estimated to be LIR = (1.79 ± 0.09) × 1014 L⊙ from spectral energy distribution modeling based on 22 photometric data points (X-ray to far-IR) with X-CIGALE, which confirmed that WISEJ0909+0002 is an ELIRG. A remarkably high LIR despite very low NH would indicate that we are witnessing a short-lived phase in which hydrogen gas along the line of sight is blown outward, whereas warm and hot dust heated by AGNs still exists. As a consequence of the eROSITA All-Sky Survey, 6.8−5.6+16 × 102 such X-ray-bright ELIRGs are expected to be discovered in the entire extragalactic sky (|b| > 10°). This can potentially be the key population to constrain the bright end of IR luminosity functions.
Extreme-UV quiet Sun brightenings observed by the Solar Orbiter/EUI
Authors: Berghmans D. , Auchère F. , Long D. M. , Soubrié E. , Mierla M. , Zhukov A. N. , Schühle U. , Antolin P. , Harra L. , Parenti S. , Podladchikova O. , Aznar Cuadrado R. , Buchlin É. , Dolla L. , Verbeeck C. , Gissot S. , Teriaca L. , Haberreiter M. , Katsiyannis A. C. , Rodriguez L. , Kraaikamp E. , Smith P.J. , Stegen K. , Rochus P. , Halain J. P. , Jacques L. , Thompson W. T. , Inhester B.
Published: April 2021

Context. The heating of the solar corona by small heating events requires an increasing number of such events at progressively smaller scales, with the bulk of the heating occurring at scales that are currently unresolved.

Aims. The goal of this work is to study the smallest brightening events observed in the extreme-UV quiet Sun.

Methods. We used commissioning data taken by the Extreme Ultraviolet Imager (EUI) on board the recently launched Solar Orbiter mission. On 30 May 2020, the EUI was situated at 0.556 AU from the Sun. Its High Resolution EUV telescope (HRIEUV, 17.4 nm passband) reached an exceptionally high two-pixel spatial resolution of 400 km. The size and duration of small-scale structures was determined by the HRIEUV data, while their height was estimated from triangulation with simultaneous images from the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory mission. This is the first stereoscopy of small-scale brightenings at high resolution.

Results. We observed small localised brightenings, also known as ‘campfires’, in a quiet Sun region with length scales between 400 km and 4000 km and durations between 10 s and 200 s. The smallest and weakest of these HRIEUV brightenings have not been previously observed. Simultaneous observations from the EUI High-resolution Lyman-α telescope (HRILya) do not show localised brightening events, but the locations of the HRIEUV events clearly correspond to the chromospheric network. Comparisons with simultaneous AIA images shows that most events can also be identified in the 17.1 nm, 19.3 nm, 21.1 nm, and 30.4 nm pass-bands of AIA, although they appear weaker and blurred. Our differential emission measure analysis indicated coronal temperatures peaking at log T ≈ 6.1 − 6.15. We determined the height for a few of these campfires to be between 1000 and 5000 km above the photosphere.

Conclusions. We find that ‘campfires’ are mostly coronal in nature and rooted in the magnetic flux concentrations of the chromospheric network. We interpret these events as a new extension to the flare-microflare-nanoflare family. Given their low height, the EUI ‘campfires’ could stand as a new element of the fine structure of the transition region-low corona, that is, as apexes of small-scale loops that undergo internal heating all the way up to coronal temperatures.
Star formation scaling relations at ∼100 pc from PHANGS: Impact of completeness and spatial scale
Authors: Pessa I. , Schinnerer E. , Belfiore F. , Emsellem E. , Leroy A. K. , Schruba A. , Kruijssen J. M. D. , Pan H.-A. , Blanc G. A. , Sanchez-Blazquez P. , Bigiel F. , Chevance M. , Congiu E. , Dale D. , Faesi C. M. , Glover S. C. O. , Grasha K. , Groves B. , Ho I. , Jiménez-Donaire M. , Klessen R. , Kreckel K. , Koch E. W. , Liu D. , Meidt S. , Pety J. , Querejeta M. , Rosolowsky E. , Saito T. , Santoro F. , Sun J. , Usero A. , Watkins E. J. , Williams T. G.
Published: April 2021

Aims.The complexity of star formation at the physical scale of molecular clouds is not yet fully understood. We investigate the mechanisms regulating the formation of stars in different environments within nearby star-forming galaxies from the Physics at High Angular resolution in Nearby GalaxieS (PHANGS) sample.

Methods.Integral field spectroscopic data and radio-interferometric observations of 18 galaxies were combined to explore the existence of the resolved star formation main sequence (Σstellarversus ΣSFR), resolved Kennicutt–Schmidt relation (Σmol. gasversus ΣSFR), and resolved molecular gas main sequence (Σstellarversus Σmol. gas), and we derived their slope and scatter at spatial resolutions from 100 pc to 1 kpc (under various assumptions).

Results.All three relations were recovered at the highest spatial resolution (100 pc). Furthermore, significant variations in these scaling relations were observed across different galactic environments. The exclusion of non-detections has a systematic impact on the inferred slope as a function of the spatial scale. Finally, the scatter of the Σmol. gas + stellarversus ΣSFRcorrelation is smaller than that of the resolved star formation main sequence, but higher than that found for the resolved Kennicutt–Schmidt relation.

Conclusions.The resolved molecular gas main sequence has the tightest relation at a spatial scale of 100 pc (scatter of 0.34 dex), followed by the resolved Kennicutt–Schmidt relation (0.41 dex) and then the resolved star formation main sequence (0.51 dex). This is consistent with expectations from the timescales involved in the evolutionary cycle of molecular clouds. Surprisingly, the resolved Kennicutt–Schmidt relation shows the least variation across galaxies and environments, suggesting a tight link between molecular gas and subsequent star formation. The scatter of the three relations decreases at lower spatial resolutions, with the resolved Kennicutt–Schmidt relation being the tightest (0.27 dex) at a spatial scale of 1 kpc. Variation in the slope of the resolved star formation main sequence among galaxies is partially due to different detection fractions of ΣSFRwith respect to Σstellar.
One-relation languages and code generators
Authors: Tran Vinh Duc , Litovsky Igor
Published: April 2021

We investigate the open problem to characterize whether the infinite power of a given language is generated by an ω-code. In case the given language is a code (i.e. zero-relation language), the problem was solved. In this work, we solve the problem for the class of one-relation languages.
Comparison of conventional drilling and helical milling for hole making in Ti6Al4V titanium alloy under sustainable dry condition
Authors: Akula Sneharika , Nayak Sadvidya N. , Bolar Gururaj , Managuli Vishwanath
Published: April 2021

Hole drilling in Ti6Al4V titanium alloy is challenging due to its poor machinability resulting from high-temperature strength and low thermal conductivity. Therefore, an evaluation of the helical milling process is carried out by comparing the thrust force, surface roughness, machining temperature, burr size, and hole diametrical accuracy with the conventional drilling process. The results indicate the advantage of the helical milling in terms of the lower magnitude of thrust force. The holes generated using helical milling displayed a superior surface finish at lower axial feed conditions, while higher axial feed conditions result in chatter due to the tool deformation. Also, the absence of a heat-affected zone (HAZ) under dry helical milling conditions indicates the work surface formation without thermal damage. Besides, a significant reduction in the size of the burrs is noted during helical milling due to lower machining temperature. Analysis of the hole diameter reinforces the capability of the helical milling process for processing H7 quality holes. Consequently, helical milling can be considered a sustainable alternative to mechanical drilling, considering its ability to machine quality holes under dry machining conditions.