bluuebunny/crossref_metadata_2025 huggingface dataset:
Cyclic quantum causal models
Authors: Barrett Jonathan , Lorenz Robin , Oreshkov Ognyan
Published: February 2021

Causal reasoning is essential to science, yet quantum theory challenges it. Quantum correlations violating Bell inequalities defy satisfactory causal explanations within the framework of classical causal models. What is more, a theory encompassing quantum systems and gravity is expected to allow causally nonseparable processes featuring operations in indefinite causal order, defying that events be causally ordered at all. The first challenge has been addressed through the recent development of intrinsically quantum causal models, allowing causal explanations of quantum processes – provided they admit a definite causal order, i.e. have an acyclic causal structure. This work addresses causally nonseparable processes and offers a causal perspective on them through extending quantum causal models to cyclic causal structures. Among other applications of the approach, it is shown that all unitarily extendible bipartite processes are causally separable and that for unitary processes, causal nonseparability and cyclicity of their causal structure are equivalent.
Forecasting influenza activity using machine-learned mobility map
Authors: Venkatramanan Srinivasan , Sadilek Adam , Fadikar Arindam , Barrett Christopher L. , Biggerstaff Matthew , Chen Jiangzhuo , Dotiwalla Xerxes , Eastham Paul , Gipson Bryant , Higdon Dave , Kucuktunc Onur , Lieber Allison , Lewis Bryan L. , Reynolds Zane , Vullikanti Anil K. , Wang Lijing , Marathe Madhav
Published: February 2021

Human mobility is a primary driver of infectious disease spread. However, existing data is limited in availability, coverage, granularity, and timeliness. Data-driven forecasts of disease dynamics are crucial for decision-making by health officials and private citizens alike. In this work, we focus on a machine-learned anonymized mobility map (hereon referred to as AMM) aggregated over hundreds of millions of smartphones and evaluate its utility in forecasting epidemics. We factor AMM into a metapopulation model to retrospectively forecast influenza in the USA and Australia. We show that the AMM model performs on-par with those based on commuter surveys, which are sparsely available and expensive. We also compare it with gravity and radiation based models of mobility, and find that the radiation model’s performance is quite similar to AMM and commuter flows. Additionally, we demonstrate our model’s ability to predict disease spread even across state boundaries. Our work contributes towards developing timely infectious disease forecasting at a global scale using human mobility datasets expanding their applications in the area of infectious disease epidemiology.
Manganese co-limitation of phytoplankton growth and major nutrient drawdown in the Southern Ocean
Authors: Browning Thomas J. , Achterberg Eric P. , Engel Anja , Mawji Edward
Published: February 2021

Residual macronutrients in the surface Southern Ocean result from restricted biological utilization, caused by low wintertime irradiance, cold temperatures, and insufficient micronutrients. Variability in utilization alters oceanic CO2 sequestration at glacial-interglacial timescales. The role for insufficient iron has been examined in detail, but manganese also has an essential function in photosynthesis and dissolved concentrations in the Southern Ocean can be strongly depleted. However, clear evidence for or against manganese limitation in this system is lacking. Here we present results from ten experiments distributed across Drake Passage. We found manganese (co-)limited phytoplankton growth and macronutrient consumption in central Drake Passage, whilst iron limitation was widespread nearer the South American and Antarctic continental shelves. Spatial patterns were reconciled with the different rates and timescales for removal of each element from seawater. Our results suggest an important role for manganese in modelling Southern Ocean productivity and understanding major nutrient drawdown in glacial periods.
Live-cell single particle tracking of PRC1 reveals a highly dynamic system with low target site occupancy
Authors: Huseyin Miles K. , Klose Robert J.
Published: February 2021

Polycomb repressive complex 1 (PRC1) is an essential chromatin-based repressor of gene transcription. How PRC1 engages with chromatin to identify its target genes and achieve gene repression remains poorly defined, representing a major hurdle to our understanding of Polycomb system function. Here, we use genome engineering and single particle tracking to dissect how PRC1 binds to chromatin in live mouse embryonic stem cells. We observe that PRC1 is highly dynamic, with only a small fraction stably interacting with chromatin. By integrating subunit-specific dynamics, chromatin binding, and abundance measurements, we discover that PRC1 exhibits low occupancy at target sites. Furthermore, we employ perturbation approaches to uncover how specific components of PRC1 define its kinetics and chromatin binding. Together, these discoveries provide a quantitative understanding of chromatin binding by PRC1 in live cells, suggesting that chromatin modification, as opposed to PRC1 complex occupancy, is central to gene repression.
Construction of intracellular asymmetry and asymmetric division in Escherichia coli
Authors: Lin Da-Wei , Liu Yang , Lee Yue-Qi , Yang Po-Jiun , Ho Chia-Tse , Hong Jui-Chung , Hsiao Jye-Chian , Liao Der-Chien , Liang An-Jou , Hung Tzu-Chiao , Chen Yu-Chuan , Tu Hsiung-Lin , Hsu Chao-Ping , Huang Hsiao-Chun
Published: February 2021

The design principle of establishing an intracellular protein gradient for asymmetric cell division is a long-standing fundamental question. While the major molecular players and their interactions have been elucidated via genetic approaches, the diversity and redundancy of natural systems complicate the extraction of critical underlying features. Here, we take a synthetic cell biology approach to construct intracellular asymmetry and asymmetric division in Escherichia coli, in which division is normally symmetric. We demonstrate that the oligomeric PopZ from Caulobacter crescentus can serve as a robust polarized scaffold to functionalize RNA polymerase. Furthermore, by using another oligomeric pole-targeting DivIVA from Bacillus subtilis, the newly synthesized protein can be constrained to further establish intracellular asymmetry, leading to asymmetric division and differentiation. Our findings suggest that the coupled oligomerization and restriction in diffusion may be a strategy for generating a spatial gradient for asymmetric cell division.
High-speed three-dimensional photoacoustic computed tomography for preclinical research and clinical translation
Authors: Lin Li , Hu Peng , Tong Xin , Na Shuai , Cao Rui , Yuan Xiaoyun , Garrett David C. , Shi Junhui , Maslov Konstantin , Wang Lihong V.
Published: February 2021

Photoacoustic computed tomography (PACT) has generated increasing interest for uses in preclinical research and clinical translation. However, the imaging depth, speed, and quality of existing PACT systems have previously limited the potential applications of this technology. To overcome these issues, we developed a three-dimensional photoacoustic computed tomography (3D-PACT) system that features large imaging depth, scalable field of view with isotropic spatial resolution, high imaging speed, and superior image quality. 3D-PACT allows for multipurpose imaging to reveal detailed angiographic information in biological tissues ranging from the rodent brain to the human breast. In the rat brain, we visualize whole brain vasculatures and hemodynamics. In the human breast, an in vivo imaging depth of 4 cm is achieved by scanning the breast within a single breath hold of 10 s. Here, we introduce the 3D-PACT system to provide a unique tool for preclinical research and an appealing prototype for clinical translation.
Publisher Correction: Genome-wide analyses of behavioural traits are subject to bias by misreports and longitudinal changes
Authors: Xue Angli , Jiang Longda , Zhu Zhihong , Wray Naomi R. , Visscher Peter M. , Zeng Jian , Yang Jian
Published: February 2021

A Correction to this paper has been published: https://doi.org/10.1038/s41467-021-21294-1.
Publisher Correction: Loss of POMC-mediated antinociception contributes to painful diabetic neuropathy
Authors: Deshpande Divija , Agarwal Nitin , Fleming Thomas , Gaveriaux-Ruff Claire , Klose Christoph S. N. , Tappe-Theodor Anke , Kuner Rohini , Nawroth Peter
Published: February 2021

A Correction to this paper has been published: https://doi.org/10.1038/s41467-021-21406-x
Author Correction: Error correction enables use of Oxford Nanopore technology for reference-free transcriptome analysis
Authors: Sahlin Kristoffer , Medvedev Paul
Published: February 2021

A Correction to this paper has been published: https://doi.org/10.1038/s41467-021-21424-9
Author Correction: Enhanced physical and cognitive performance in active duty Airmen: evidence from a randomized multimodal physical fitness and nutritional intervention
Authors: Zwilling Christopher E. , Strang Adam , Anderson Evan , Jurcsisn Jennifer , Johnson Erica , Das Tapas , Kuchan Matthew J. , Barbey Aron K.
Published: February 2021

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
TDCS effects on pointing task learning in young and old adults
Authors: Kaminski E. , Engelhardt M. , Hoff M. , Steele C. , A.Villringer  , Ragert P.
Published: February 2021

Skill increase in motor performance can be defined as explicitly measuring task success but also via more implicit measures of movement kinematics. Even though these measures are often related, there is evidence that they represent distinct concepts of learning. In the present study, the effect of multiple tDCS-sessions on both explicit and implicit measures of learning are investigated in a pointing task in 30 young adults (YA) between 27.07 ± 3.8 years and 30 old adults (OA) between 67.97 years ± 5.3 years. We hypothesized, that OA would show slower explicit skill learning indicated by higher movement times/lower accuracy and slower implicit learning indicated by higher spatial variability but profit more from anodal tDCS compared with YA. We found age-related differences in movement time but not in accuracy or spatial variability. TDCS did not facilitate learning neither in explicit nor implicit parameters. However, contrary to our hypotheses, we found tDCS-associated higher accuracy only in YA but not in spatial variability. Taken together, our data shows limited overlapping of tDCS effects in explicit and implicit skill parameters. Furthermore, it supports the assumption that tDCS is capable of producing a performance-enhancing brain state at least for explicit skill acquisition.
High-temperature high-pressure microfluidic system for rapid screening of supercritical CO2 foaming agents
Authors: Gizzatov Ayrat , Pierobon Scott , AlYousef Zuhair , Jian Guoqing , Fan Xingyu , Abedini Ali , Abdel-Fattah Amr I.
Published: February 2021

CO2 foam helps to increase the viscosity of CO2 flood fluid and thus improve the process efficiency of the anthropogenic greenhouse gas’s subsurface utilization and sequestration. Successful CO2 foam formation mandates the development of high-performance chemicals at close to reservoir conditions, which in turn requires extensive laboratory tests and evaluations. This work demonstrates the utilization of a microfluidic reservoir analogue for rapid evaluation and screening of commercial surfactants (i.e., Cocamidopropyl Hydroxysultaine, Lauramidopropyl Betaine, Tallow Amine Ethoxylate, N,N,N′ Trimethyl-N′-Tallow-1,3-diaminopropane, and Sodium Alpha Olefin Sulfonate) based on their performance to produce supercritical CO2 foam at high salinity, temperature, and pressure conditions. The microfluidic analogue was designed to represent the pore sizes of the geologic reservoir rock and to operate at 100 °C and 13.8 MPa. Values of the pressure drop across the microfluidic analogue during flow of the CO2 foam through its pore network was used to evaluate the strength of the generated foam and utilized only milliliters of liquid. The transparent microfluidic pore network allows in-situ quantitative visualization of CO2 foam to calculate its half-life under static conditions while observing if there is any damage to the pore network due to precipitation and blockage. The microfluidic mobility reduction results agree with those of foam loop rheometer measurements, however, the microfluidic approach provided more accurate foam stability data to differentiate the foaming agent as compared with conventional balk testing. The results obtained here supports the utility of microfluidic systems for rapid screening of chemicals for carbon sequestration or enhanced oil recovery operations.
Hemostatic and antibacterial PVA/Kaolin composite sponges loaded with penicillin–streptomycin for wound dressing applications
Authors: Tamer Tamer M. , Sabet Maysa M. , Omer Ahmed M. , Abbas Eman , Eid Alaa I. , Mohy-Eldin Mohamed S. , Hassan Mohamed A.
Published: February 2021

Hemorrhage is the major hindrance over the wound healing, which triggers microbial infections and might provoke traumatic death. Herein, new hemostatic and antibacterial PVA/Kaolin composite sponges were crosslinked using a freeze-thawing approach and boosted by penicillin–streptomycin (Pen-Strep). Physicochemical characteristics of developed membranes were analyzed adopting Fourier transformed infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), a thermal gravimetric analyzer (TGA), and differential scanning calorimetry (DSC). Furthermore, the impacts of kaolin concentrations on porosity, swelling behavior, gel fraction, and degradation of the membranes were investigated. SEM analyses revealed a spongy-like structure of hydrogels associated with high dispersion of kaolin inside PVA matrix. The thermal characteristics of PVA/Kaolin were significantly ameliorated compared to the prime PVA. Moreover, the results exhibited significant variations of swelling performance, surface roughness and pore capacity due to the alterations of kaolin contents. Besides, the adhesive strength ability was manifestly enhanced for PVA-K0.1 sponge. Biomedical evaluations including antibacterial activity, blood clotting index and thrombogenicity of the membranes were studied. The contact of PVA/Kaolin to blood revealed notable augmentation in blood clotting. Furthermore, the incorporation of kaolin into PVA presented mild diminution in antibacterial activities. Moreover, PVA/Kaolin composites illustrated no cellular toxicity towards fibroblast cells. These remarkable features substantiate that the PVA-K0.1 sponge could be applied as a multifunctional wound dressing.
Asymptotic freedom and noninteger dimensionality
Authors: Kak Subhash
Published: February 2021

This paper shows that below a critical value of dimensionality that lies between two and three, the potential between objects begins to fall as the energy levels increase. For dimensionality below two, the potential becomes constant irrespective of separation and the force between them disappears, which represents a new paradigm of asymptotic freedom. Since asymptotic freedom is at the basis of many applications such as those associated with strange metals, unconventional superconductors, and fractional quantum Hall states, the new paradigm can have novel applications. It also is of relevance to the study of anomalous mechanical effects that are important in metamaterials.
Author Correction: Prebiotic effects of yeast mannan, which selectively promotes Bacteroides thetaiotaomicron and Bacteroides ovatus in a human colonic microbiota model
Authors: Oba Shunsuke , Sunagawa Tadahiro , Tanihiro Reiko , Awashima Kyoko , Sugiyama Hiroshi , Odani Tetsuji , Nakamura Yasunori , Kondo Akihiko , Sasaki Daisuke , Sasaki Kengo
Published: February 2021

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Role of landslides on the volume balance of the Nepal 2015 earthquake sequence
Authors: Valagussa A. , Frattini P. , Valbuzzi E. , Crosta G. B.
Published: February 2021

The 7.8 Mw earthquake that struck Nepal on April 25th, 2015 triggered over 21,000 landslides over an area of more than 25,000 km2. These landslides contributed to mass wasting, partially compensating the tectonic uplift by the earthquake. In this paper we quantify the volume balance resulting from the 2015 earthquake uplift (or subsidence) and landslide erosion. Starting from a new complete earthquake-induced landslide inventory, we calculated landslide volume by adopting different strategies for low-mobility and high-mobility landslides, considering also the potential supply of sediments to the drainage network. The results show that the contribution of earthquake-induced landslides to erosion is about one order of magnitude smaller than the vertical coseismic displacement. We found landslide volume values, due to the 2015 Nepal earthquake, ranging between 251 (− 15/ + 16) Mm3 up to 1503 (− 183/ + 210) Mm3 based on the adopted method, and a volume due to coseismic vertical displacement of 2134 (± 1269) Mm3 for the whole area. The volume balance of the 2015 Nepal earthquake is strongly dominated by tectonic displacement. We show that these estimates depend on several uncertainties. We identified and quantified uncertainties related to: (1) the choice of empirical volume-area scaling relationships and their parameters; (2) the completeness and quality of landslide inventory through comparison with available inventories; (3) the approach adopted for the assessment of elongated landslide volume; (4) the InSAR displacement data.
Removal of diclofenac from aqueous solutions by adsorption on thermo-plasma expanded graphite
Authors: Cuccarese Marco , Brutti Sergio , De Bonis Angela , Teghil Roberto , Mancini Ignazio Marcello , Masi Salvatore , Caniani Donatella
Published: February 2021

The adsorption of diclofenac on thermo-plasma expanded graphite (a commercial product) from water solutions was investigated. The adsorbent material was characterized by SEM, TEM, BET, Raman and X-ray diffraction analyses. Typical diffractogram and Raman spectrum of graphitic material, dimension of 24.02 nm as crystallite dimension and a surface area of 47 m2 g−1were obtained. The effect of pH on the adsorption capacity was evaluated in the range 1–7 and the adsorption mechanism was described by kinetic and isothermal studies. Pseudo-second order and Dubinin–Radushkevich models agreed with theoretical values of adsorption capacity (i.e. 400 and 433 mg g−1, respectively) and resulted to be the best fit for kinetics and isothermal experimental data. The thermodynamics of the process was evaluated by plotting the adsorption capacity/concentration ratio at the equilibrium as a function of different values of the multiplicative inverse of temperature. Moreover, the adsorbent regeneration was also investigated, comparing two different remediation techniques. Solvent washing performed with NaOH 0.2 M and thermo-treatment carried out by heating in an oven at 105 °C for 2 h and then at 200 °C for 4 h. The thermo-treatment was the best technique to regenerate the adsorbent, ensuring same performance after 4 cycles of use and regeneration.
Publisher Correction: Algorithmic and human prediction of success in human collaboration from visual features
Authors: Saveski Martin , Awad Edmond , Rahwan Iyad , Cebrian Manuel
Published: February 2021

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
The extraction of phenolic acids and polysaccharides from Lilium lancifolium Thunb. using a deep eutectic solvent
Authors: Chen Lin , Yang Yang-Yu , Zhou Rong-rong , Fang Liang-zi , Zhao Di , Cai Ping , Yu Rong , Zhang Shui-han , Huang Jian-hua
Published: February 2021

This study provided a new application of deep eutectic solvents (DESs) in the simultaneous extraction of phenolic acids and polysaccharides from the bulbs of Lilium lancifolium Thunb.
Unveiling the strong dependence of the α-relaxation dispersion on mixing thermodynamics in binary glass-forming liquids
Authors: Liu Xin , Li Xudong , Wang Ji , Feng Shidong , Wang Li-Min
Published: February 2021

The dynamic studies in binary molecular glass-forming mixtures with distinct mixing enthalpy revealed strong dependence of the structural α-relaxation dispersion on mixing thermodynamics using enthalpy and dielectric relaxation measurements.
Hypoglycemic activity of Origanum vulgare L. and its main chemical constituents identified with HPLC-ESI-QTOF-MS
Authors: Yu Huawei , Zhang Panpan , Liu Hongbing , Sun Xiaojuan , Liang Jichao , Sun Lijuan , Chen Yong
Published: February 2021

Origanum vulgare L. leaf extract showed promising hypoglycemic activity through gluconeogenesis, lipid synthesis and relieving oxidative stress signalling pathway, and its potential active phenolic compounds were also identified by HPLC-ESI-Q-TOF-MS method.
One-pot self-assembly synthesis of Ni-doped ordered mesoporous carbon for quantitative hydrogenation of furfural to furfuryl alcohol
Authors: Tang Yiwei , Qiu Mo , Yang Jirui , Shen Feng , Wang Xiaoqi , Qi Xinhua
Published: February 2021

Ni-Doped OMC with high catalytic activity and stability for furfural hydrogenation to furfuryl alcohol was prepared by a one-pot evaporation-induced self-assembly process with biomass-derived gallic acid as carbon precursor and Ni2+ as crosslinker.
A shape-persistent arylene ethynylene macrocycle with a multiple acetamide modified cavity: synthesis and gelation
Authors: Ruan Yang , Li Qian-Hui , Shu Lijin , Wan Jun-Hua
Published: February 2021

Strong H-bonds suppress π–π stacking leading to an AIEE gel from a planar conjugated macrocycle.
SYBR Green I promotes melamine binding to poly-thymine DNA and FRET-based ratiometric sensing
Authors: He Fan , Shen Yudong , Liu Juewen
Published: February 2021

Using SYBR Green I for DNA melting experiments, polythymine DNA binding to melamine was found to be an intramolecular reaction, allowing the design of a FRET-based biosensor and its sensitivity was enhanced by SYBR Green I.
Synthesis and characterization of phosphorous(iii) diisocyanate and triisocyanate
Authors: Hu Dandan , Lu Bo , Song Chao , Zhu Bifeng , Wang Lina , Bernhardt Eduard , Zeng Xiaoqing
Published: February 2021

Two polyisocyanates of phosphorous(iii), ClP(NCO)2and P(NCO)3have been synthesized and structurally characterized.
Triplet state (anti)aromaticity of some monoheterocyclic analogues of benzene, naphthalene and anthracene
Authors: Baranac-Stojanović Marija , Stojanović Milovan , Aleksić Jovana
Published: February 2021

By employing DFT calculations, we show the influence of heteroatom substitution on the triplet state (anti)aromaticity of benzene, naphthalene and anthracene.
Electromagnetic characterization of transparent conducting thin films using two‐port flange coaxial probe and thin‐film transfer matrix method
Authors: Sadat Saeid , Shokooh‐Saremi Mehrdad , Mirsalehi Mir Mojtaba
Published: February 2021

An efficient method to determine the electromagnetic characteristics of transparent conducting oxide (TCO) thin films is presented herein. When a two‐port flange coaxial probe is used for electromagnetic characterization, it is important to note that since the thickness of the film is very thin, it should be taken into account that the measured S parameters not only correspond to the thin film, but also to the substrate. The main idea of this study is to exploit the S parameters corresponding solely to the thin film by employing transfer matrix method. Then, by using the obtained S parameters, the effective conductivity (σ) and relative permittivity (εr) of the TCO thin film are determined. By applying this method to a sample under test, the conductivity and relative permittivity are obtained in the order of 105 (S/m) and 106 in the 2–20 GHz frequency range, respectively. These results are compared with those obtained by the Nicolson–Ross–Wier and open‐ended coaxial probe methods. Simulation results show that when the TCO thin film thickness reaches 0.5 mm, its conductivity increases up to two times. Also, when the gap between the coaxial probe and the thin‐film surface is 0.1 mm, the conductivity approaches zero. Using this method, the material and thickness of the substrate have slight effect on determining the electromagnetic characteristics.
Flaw characterization in conductive media based on pulsed Eddy current measurements: A fast non‐iterative inversion approach
Authors: Miorelli Roberto , Skarlatos Anastassios , Reboud Christophe
Published: February 2021

This paper proposes a non‐iterative procedure for flaw(s) characterization based on Pulsed Eddy Current Testing (PECT) signals analysis. The adopted inversion strategy is based on the use of supervised statistical learning algorithms. A numerical forward solver, based on the Finite Integration Technique (FIT), is used for the generation of the training data (the input‐targets couples of the learning algorithm). Predictions are then carried out in almost real‐time using a non‐linear kernel based regression method, known as kernel ridge regression. It turns out that the direct fit of the regression model to the raw PECT signals may lead to poor prediction accuracy due to the large cardinality of PECT signals. To remedy this problem, an adaptive sampling strategy has been adopted in this work. The performance of the proposed methodology is discussed and compared with solutions proposed in the literature.
Cosmic ray sputtering yield of interstellar ice mantles
Authors: Dartois E. , Chabot M. , Id Barkach T. , Rothard H. , Boduch P. , Augé B. , Agnihotri A. N.
Published: February 2021

Aims. Cosmic-ray-induced sputtering is one of the important desorption mechanisms at work in astrophysical environments. The chemical evolution observed in high-density regions, from dense clouds to protoplanetary disks, and the release of species condensed on dust grains, is one key parameter to be taken into account in interpretations of both observations and models.

Methods. This study is part of an ongoing systematic experimental determination of the parameters to consider in astrophysical cosmic ray sputtering. As was already done for water ice, we investigated the sputtering yield as a function of ice mantle thickness for the two next most abundant species of ice mantles, carbon monoxide and carbon dioxide, which were exposed to several ion beams to explore the dependence with deposited energy.

Results. These ice sputtering yields are constant for thick films. It decreases rapidly for thin ice films when reaching the impinging ion sputtering desorption depth. An ice mantle thickness dependence constraint can be implemented in the astrophysical modelling of the sputtering process, in particular close to the onset of ice mantle formation at low visual extinctions.
Long-term evolution of three light bridges developed on the same sunspot
Authors: Griñón-Marín A. B. , Pastor Yabar A. , Centeno R. , Socas-Navarro H.
Published: February 2021

One important feature of sunspots is the presence of light bridges. These structures are elongated and bright (as compared to the umbra) features that seem to be related to the formation and evolution of sunspots. In this work, we studied the long-term evolution and the stratification of different atmospheric parameters of three light bridges formed in the same host sunspot by different mechanisms. To accomplish this, we used data taken with the GREGOR Infrared Spectrograph installed at the GREGOR telescope. These data were inverted to infer the physical parameters of the atmosphere where the observed spectral profiles were formed of the three light bridges. We find that, in general, the behaviour of the three light bridges is typical of this kind of structure with the magnetic field strength, inclination, and temperature values between the values at the umbra and the penumbra. We also find that they are of a significantly non-magnetic character (particularly at the axis of the light bridges) as it is deduced from the filling factor. In addition, within the common behaviour of the physical properties of light bridges, we observe that each one exhibits a particular behaviour. Another interesting result is that the light bridge cools down, the magnetic field decreases, and the magnetic field lines get more inclined higher in the atmosphere. Finally, we studied the magnetic and non-magnetic line-of-sight velocities of the light bridges. The former shows that the magnetic component is at rest and, interestingly, its variation with optical depth shows a bi-modal behaviour. For the line-of-sight velocity of the non-magnetic component, we see that the core of the light bridge is at rest or with shallow upflows and clear downflows sinking through the edges.
Estimates of the change rate of solar mass and gravitational constant based on the dynamics of the Solar System
Authors: Pitjeva E. V. , Pitjev N. P. , Pavlov D. A. , Turygin C. C.
Published: February 2021

The estimate of the change rate of the solar gravitational parameter d(GM⊙)∕dt is obtained from processing modern positional observations of planets and spacecraft. Observations were processed and parameters were determined basing on the numerical planetary ephemeris EPM2019. The obtained annual decrease in solar mass M⊙ accounts for the loss through radiation Ṁ⊙rad, through the outgoing solar wind Ṁ⊙wind, and for the material falling on the Sun Ṁ⊙fall. The estimated relative value is within −13.4×10−14 < (Ṁ⊙/Ṁ⊙)rad+wind+fall < −8.7×10−14 per year. The following range for the change rate of the gravitational constant G was obtained: −2.9 × 10−14 < Ġ∕G < + 4.6 × 10−14 per year (3σ). The new result reduces the interval for the change in G and narrows the limits of possible deviations for alternative gravitational theories from general relativity.
How flux feeding causes eruptions of solar magnetic flux ropes with the hyperbolic flux tube configuration
Authors: Zhang Quanhao , Liu Rui , Wang Yuming , Zhou Zhenjun , Zhuang Bin , Li Xiaolei
Published: February 2021

Coronal magnetic flux ropes are generally considered to be the core structure of large-scale solar eruptions. Recent observations found that solar eruptions could be initiated by a sequence of flux feeding, during which chromospheric fibrils rise upward from below, and merge with a pre-existing prominence. Further theoretical study has confirmed that the flux feeding mechanism is efficient in causing the eruption of flux ropes that are wrapped by bald patch separatrix surfaces. But it is unclear how flux feeding influences coronal flux ropes that are wrapped by hyperbolic flux tubes (HFTs), and whether it is able to cause the flux-rope eruption. In this paper, we use a 2.5-dimensional magnetohydrodynamic model to simulate the flux feeding processes in HFT configurations. It is found that flux feeding injects axial magnetic flux into the flux rope, whereas the poloidal flux of the rope is reduced after flux feeding. Flux feeding is able to cause the flux rope to erupt, provided that the injected axial flux is large enough so that the critical axial flux of the rope is reached. Otherwise, the flux-rope system evolves to a stable equilibrium state after flux feeding, which might be even farther away from the onset of the eruption, indicating that flux feeding could stabilize the rope system with the HFT configuration in this circumstance.
Mapping the core of the Tarantula Nebula with VLT-MUSE
Authors: Castro N. , Crowther P. A. , Evans C. J. , Vink J. S. , Puls J. , Herrero A. , Garcia M. , Selman F. J. , Roth M. M. , Simón-Díaz S.
Published: February 2021

We present the spectroscopic analysis of 333 OB-type stars extracted from VLT-MUSE observations of the central 30 × 30 pc of NGC 2070 in the Tarantula Nebula on the Large Magellanic Cloud, the majority of which are analysed for the first time. The distribution of stars in the spectroscopic Hertzsprung-Russell diagram (sHRD) shows 281 stars in the main sequence. We find two groups in the main sequence, with estimated ages of 2.1 ± 0.8 and 6.2 ± 2 Myr. A subgroup of 52 stars is apparently beyond the main sequence phase, which we consider to be due to emission-type objects and/or significant nebular contamination affecting the analysis. As in previous studies, stellar masses derived from the sHRD are systematically larger than those obtained from the conventional HRD, with the differences being largest for the most massive stars. Additionally, we do not find any trend between the estimated projected rotational velocity and evolution in the sHRD. The projected rotational velocity distribution presents a tail of fast rotators that resembles findings in the wider population of 30 Doradus. We use published spectral types to calibrate the He Iλ4921/He IIλ5411 equivalent-width ratio as a classification diagnostic for early-type main sequence stars when the classical blue-visible region is not observed. Our model-atmosphere analyses demonstrate that the resulting calibration is well correlated with effective temperature.
The Risk Quantification Evaluation Strategy for the Distribution Line based on EMLR
Authors: Xuesong Tang , Bin Wu , Guangming Yu , Fulai Fan , Jinyu Qu , Hongjiang Du , Yunhan Wang
Published: February 2021

The electric power distribution grid directly serves the ordinary users, the stability and reliability of which are crucial to production and life. The traditional operation and maintenance of the distribution grid is based on experience and cannot scientifically predict the state of line faults. In this paper, stepwise regression is used to screen out 8 key influencing factors of line faults, and principal component analysis is performed to find the risk value of each line; so that establishes multiple linear and exponential regression equations for the line risk value. According to the existing data, the risk of the line is predicted, and the GABP neural network model is built so as to accurately predict the risk value of the line.
The LiFePO4battery sorting method based on temperature analysis
Authors: He Zhenyu , Wu Xijin , Li Xin , Wang Qingshan , Li Yan
Published: February 2021

Using temperature as the main state basis for sorting the LiFePO4 battery can solve the problem of insufficient response to the internal working state of the cell. By tracking and monitoring the status of each cell inside the module, which can reflect the consistency of the complex system after large-capacity grouping. Here, the dynamic temperature change of the LiFePO4 battery is detected, the temperature rise and the temperature rise rate are compared. The corresponding temperature rise rate of the old cell were significantly higher than the new cell. The temperature difference can be used to judge the consistency of the single cells in the battery module.
The Influence of Urban Sprawl on Household Power Intensity——Evidence from China's Urban Panel Data
Authors: Du Cong , Shen Jie , Liu Xiuyan , Qin Meng
Published: February 2021

The paper measures the yearly urban sprawl index and household power intensity of 285 prefecture-level and Municipality cities in China from 2004 to 2017. Through the establishment of a fixed effect model, random effect model and systematic GMM model, this paper empirically analyze the impact of urban sprawl on household power intensity, and found that there is a significant and positive effect of urban sprawl on household power intensity, that is, the higher the urban sprawl, the lower the efficiency of household electricity energy utilization will be, and this effect has a cogent robustness. On this basis, the establishment of a mediating effect model found that population agglomeration playes a significant role of the partial mediating effect in the process of urban sprawl affecting household power intensity. The conclusion of this paper provides some policy implications for the scientific and reasonable urban planning in the process of urbanization in China from the perspective of optimizing household power intensity.
Experimental study on unconfined compressive strength of expansive soil improved by lignin and cement
Authors: Zhang Yuguo , Zhang Weijie , Shi Xiaojie , Guo Tai , Chen Zhenghao
Published: February 2021

Aiming at the question of improvement expansive soil in Nanyang area, the composite improvement method of lignin and cement was adopted. Based on the unconfined compressive strength test, the variation law of unconfined compressive strength of improved expansive soil with different lignin content, different compaction degree and different curing age was studied. The test results show that the composite of lignin and cement can effectively improve the unconfined compressive strength of expansive soil. The unconfined compressive strength of L-C (lignin and cement) improved expansive soil reaches the maximum when the cement content is fixed at 4% and the lignin content is 1%. The unconfined compressive strength of L-C improved soil increases with the increase of compaction degree and curing age, and the strength growth mainly concentrated in the first 7 days of curing age. From the point of improvement mechanism, the hydration and gelation reaction of cement occur in expansive soil, and gel material with higher strength is formed to enhance the strength of expansive soil. The appropriate amount of lignin can fill the pores between soil particles and make the connection between soil particles more closely, so as to improve the strength of expansive soil.
Micro-market Operation Strategy Based on Two-way Bidding of Electric Vehicles and Battery Energy Storage
Authors: Zou Dazhong , Zhang Gang , Lu Shuai , Dai Yinping
Published: February 2021

To solve the problem that charging is constrained by the capacity of distribution facilities under high penetration of electric vehicles (EVs), this paper proposes to improve EV charging capacity through battery energy storage (BES) and presents the design of a locally organized market, namely micro-market, that manages the energy transactions between EVs and the BES. When the load of a distribution system approaches its limit, additional EV charging demand is met by the BES, and the price is determined in an automated two-way bidding process. This mechanism can increase EV charging capacity as well as provide an additional revenue stream for the BES in distribution systems. The presented micro-market design ensures the balance between revenue and expenditure of market participants. The organization and settlement process of the micro-market are demonstrated using an example case, and the effectiveness of the design is proved.
Effects of alloy elements on mechanical properties of low alloy wear resistant steel
Authors: Zhang Wenfeng , Liu Zhong , Li Tianming , Liu Xiaogang , Xiong Wei
Published: February 2021

This work is mainly concerning with effects of Carbon, Nickel and vanadium on mechanical properties of low alloy wear resistant steel. the results showed that The experimental steels yielded their best comprehensive properties at 940 °C of quenching and at 200 °C of tempering for 0.33 wt% C steel, at 940 °C of quenching and at 220°C of tempering for 0.38 wt% C steel, and at 920°C of quenching and at 230 °C of tempering for 0.4 wt% C steel, respectively.3% Ni steel yielded the best property at 900 °C quenching and 200 °C tempering, while 5% Ni steel was 920 °C quenching and 200 °C tempering. The best property yielded at 940 °C quenching and 200 °C tempering for the Vanadium addition steel.
Analysis of the structure of door bottom drop sealing device
Authors: Fei Yuan
Published: February 2021

-Drop Seals Is A Kind Of Hardware That Can Solve The Tightness Of The Door Bottom. This article will briefly introduce the common structural features of this hardware and analyze its impact on the sound insulation of the door leaf according to the experiment. Based on the comparative analysis of 5 sets of data, the experiment proved the effectiveness of the drop seals for the door bottom seal.
Principle and Model Block Diagrams of Cd Content Monthly Variation in Surface and Bottom Waters in Central Bay
Authors: Yang Dongfang , Yang Dong , Ling Weifeng , Lin Dong , Li Haixia
Published: February 2021

According to survey data, in Jiaozhou Bay in 1992, the vertical distribution of Cd content and monthly changes in the surface and the bottom of the central sea area of Jiaozhou Bay were studied, and monthly changes, migration processes and variational principles of the Cd content in surface and bottom water were determined. In May, August, and October, the water body that the main sea current did not pass through were those in the center of the bay. Cd content in central surface water of Jiaozhou Bay was not transported from any source outside the bay from May to October. The results showed that Cd content transported by the main sea current changed from low to high in October, May and August; Cd content transported by the bay current changed from low to high: October, August and May; Cd content in surface water in the bay center changed from low to high in: August, May and October; Cd content in the bottom bay center changed from low to high in May, October and August. Thus, from May to October, monthly changes in these four parts were different. For this reason, the monthly variation principle of Cd content in the surface and bottom waters of the bay was proposed. In addition, the model block diagrams were established to show the change process and principle of Cd content deposition and migration. The principle shows that the bay current has no direct effect on the surface water in the center of the bay from May to October. However, the bottom water body in the center of Jiaozhou Bay was greatly affected, and the surface water body in the center of Jiaozhou Bay was further affected by the upwelling.
Research on Persuasive Design of Waste Sorting APP
Authors: Hao Yuan , Xiaoyan Xu
Published: February 2021

China’s domestic waste classification policy is gradually being implemented, so that the domestic waste classification and processing industry is also developing rapidly and showing new characteristics of the digital age. Mobile phone application to assist urban residents in decision-making is one of the digital solutions for domestic waste classification. This article uses research methods such as literature research, case analysis and user interviews to sort out the characteristics and problems of existing waste sorting APPs, and analyze the characteristics of user waste sorting behavior. Then summarized based on the theory of persuasion, and finally proposed the persuasion design strategy of waste sorting APP from the three dimensions of motivation, ability, and triggering factors. It is expected that while satisfying the needs of users for assisting in waste sorting operations and optimizing user experience, it can further guide users to enhance their awareness of environmental protection and public welfare, participate in environmental protection public welfare activities, and bring better social benefits.
Under the background of “Internet Plus”, the innovation of the training mode of tourism management professionals in higher vocational colleges is discussed
Authors: Liao Zichao
Published: February 2021

With the continuous development of society, China’s Internet science and technology and computer information technology are also developing and progressing. In this process, Internet technology has had a great impact on many professional fields, Internet technology has become an indispensable part of people’s lives. With the concept of “Internet Plus”, various industries have set off a trend about the combination of the Internet and traditional fields. The field of education is no exception, in the “Internet plus” background of the field of education has also set off a wave of reform, the current teaching of vocational colleges and universities are gradually combined with Internet technology. The traditional offline teaching concept and teaching method can not meet the needs of tourism management talents in the society at the time. Therefore, under the background of the Internet, the combination of education and the Internet is an inevitable trend, in the training of tourism management professionals in domestic vocational colleges, Internet technology has greatly promoted the training of tourism professionals. Therefore, this paper mainly revolves around the innovative development of the training mode of tourism management personnel in higher vocational colleges under the background of “Internet plus”, and hopes that this paper can provide a reference for the research on the training mode of tourism management professionals in higher vocational education.
Can cost sharing contracts coordinate green supply chains based on manufacturers’ overconfidence
Authors: Zhou Hui
Published: February 2021

Cost sharing contracts is one of the most common contracts to coordinate green supply chains. In this paper, we examine whether it can coordinate green supply chains in the set up of overconfidence. We assume that the manufacturer is overconfident and the retailer is rational. The manufacturer overestimates consumers’ sensitivity to product greenness and accurately estimates the uncertainty of demand. The overconfident manufacturer and the rational retailer cooperate through cost sharing contracts. Then, we construct a game theoretical model to analyze the impact of manufacturers’ overconfident on product greenness, pricing, profit and supply chain cooperation. At last, a numerical experimentation is presented. We find that, (1) the product greenness, wholesale price and retail price increase with the manufacturer’s overconfidence as well as the retailer’s cost sharing proportion. (2) no matter how much the cost sharing proportion is, the profit of manufacturers and retailers decreases with the manufacturer’s overconfidence level. (3) cost sharing contracts can achieve the green supply chain coordination in rational setting. But under manufacturers’ overconfidence, it cannot.
Research on Determinants of Inclusiveness of China Rural Infrastructure
Authors: Jiang Aichun , Chen Chuan
Published: February 2021

Since the founding of the theory of inclusive growth, it has been widely researched worldwide. However, most of the researches are more focused on the macro-level measurement, but lack of systematic research on micro-level implementation and viable path. From a micro view prospective, this article studies Chinese rural infrastructure with its influence factors and defining inclusive infrastructure. The literature review will clarify the influencing factors of inclusive infrastructure, as to lay the assessment and policy decision foundation of rural infrastructure.
Effects of tilt angle on droplets condensation on hydrophobic surface
Authors: He Zhenhua , Wang Shuxiang , Liu Hongjie , Tong Junjie , He Zuyang
Published: February 2021

Condensation surface modification was an important research direction to realize droprise condensation and erhance heat transfer. In order to explore the condensation process and mechanism of droplets on the hydrophobic surface, the condensation process of droplets on the natural Donghu lotus leaves with tilt angle of 30°,60° and 90° were studied. The results show that the tilt angle had a significant effect on the droplets condensation behavior on Donghu lotus leaves hydrophobic surface. Increasing the tilt angle would short the detachment time of condensate droplets. The growth rate of droplets increased with the increase of hydrophobic surface tilt angle. And the condensation droplets diameter also decreased with the increase of incl ination angle.
Researching Technology and Equipment about the Vertical Billet in the Intelligent Manufacturing Production Line
Authors: Zhong Bo , Zhou Wenjin , Wang Yanlong , Zhang Qiqi
Published: February 2021

Firstly, this text is introducing the traditional technology of vertical billet. Secondly, the text is describing technological process and equipment principle about first and second generation vertical billet machine. Thirdly, the text is illustrating the second generation machine’s superiorities by contrasting. Finally, we have put forward the thought of optimal to the second generation machine.