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Compared to the processing of the words alone, the processing of Chinese two-character words in sentences will be closer to a natural scenario, and the understanding of the sentence will be influenced by both linguistic contexts and the non-linguistic contexts. This study, in a moving-window self-paced word-by-word sentence reading task, experimentally explored the processing of Chinese sentences with emotional two-character words using reversible words and reaction time as materials and index respectively. The experimental results showed that emotional words may facilitate the processing of its following two words; there might exist subsequent processing in the third word behind the emotional word; there might exist lexical access and whole-word access, processing of morpheme positioned information in the processing of Chinese two-character words in sentence reading; the processing of Chinese two-character words may be similar with that of word alone. This study expands the research of Chinese emotional two-character words processing.

In this paper, we present a model-independent approach to calibrate the largest quasar sample. Calibrating quasar samples is essentially constraining the parameters of the linear relation between the $\log$ of the ultraviolet (UV) and X-ray luminosities. This calibration allows quasars to be used as standardized candles. There is a strong correlation between the parameters characterizing the quasar luminosity relation and the cosmological distances inferred from using quasars as standardized candles. We break this degeneracy by using Gaussian process regression to model-independently reconstruct the expansion history of the Universe from the latest type Ia supernova observations. Using the calibrated quasar dataset, we further reconstruct the expansion history up to redshift of $z\sim 7.5$. Finally, we test the consistency between the calibrated quasar sample and the standard $\rm{\Lambda}CDM$ model based on the posterior probability distribution of the GP hyperparameters. Our results show that the quasar sample is in good agreement with the standard $\rm{\Lambda}CDM$ model in the redshift range of the supernova, despite of mildly significant deviations taking place at higher redshifts. Fitting the standard $\rm{\Lambda}CDM$ model to the calibrated quasar sample, we obtain a high value of the matter density parameter $\Omega_m = 0.382^{+0.045}_{-0.042}$, which is marginally consistent with the constraints from other cosmological observations., Comment: 9 pages, 7 figures

The invariance of the speed of light in the distant universe has profound significance for fundamental physics. In this paper, we propose a new model-independent method to test the invariance of the speed of light $c$ at different redshifts by combining the strong gravitational lensing (SGL) systems and the observations of type-Ia supernovae (SNe Ia). All the quantities used to test the deviation of $c$ come from the direct observations, and the absolute magnitudes of SNe Ia need not to be calibrated. Our results show that the speed of light in the distant universe is no obvious deviation from the constant value $c_0$ within the uncertainty based on current observations. Moreover, we conclude that the currently compiled SGL and SNe Ia Pantheon samples may achieve much higher precision $\Delta c/c\sim10^{-2}$ for the deviation of $c$ than all previously considered approaches. The forthcoming data from the Legacy Survey of Space and Time and Wide-Field InfraRed Space Telescope will achieve more stringent testing for deviation of the SOL (at the level of $\Delta c/c \sim10^{-3}$) by using our model-independent method. Finally, we discuss the potential ways in which our technique might be improved, focusing on the treatment of possible sources of systematic uncertainties., Comment: 9 pages, 5 figures, accepted for publication in MNRAS

Apomixis, or asexual seed formation, is prevalent in Citrinae via a mechanism termed nucellar or adventitious embryony. Here, multiple embryos of a maternal genotype form directly from nucellar cells in the ovule and can outcompete the developing zygotic embryo as they utilize the sexually derived endosperm for growth. Whilst nucellar embryony enables the propagation of clonal plants of maternal genetic constitution, it is also a barrier to effective breeding through hybridization. To address the genetics and evolution of apomixis in Citrinae, a chromosome-level genome of the Hongkong kumquat (Fortunella hindsii) was assembled following a genome-wide variation map including structural variants (SVs) based on 234 Citrinae accessions. This map revealed that hybrid citrus cultivars shelter genome-wide deleterious mutations and SVs into heterozygous states free from recessive selection, which may explain the capability of nucellar embryony in most cultivars during Citrinae diversification. Analyses revealed that parallel evolution may explain the repeated origin of apomixis in different genera of Citrinae. Within Fortunella, we found that apomixis of some varieties originated via introgression. In apomictic Fortunella, the locus associated with apomixis contains the FhRWP gene, encoding an RWP-RK domain-containing protein previously shown to be required for nucellar embryogenesis in Citrus. We found the heterozygous SV in the FhRWP and CitRWP promoters from apomictic Citrus and Fortunella, due to either two or three miniature inverted transposon element (MITE) insertions. A transcription factor, FhARID, encoding an AT-rich interaction domain-containing protein binds to the MITEs in the promoter of apomictic varieties, which facilitates induction of nucellar embryogenesis. This study provides evolutionary genomic and molecular insights into apomixis in Citrinae and has potential ramifications for citrus breeding.

In this paper, we quantify the ability of multiple measurements of high-redshift quasars (QSOs) to constrain several theories of modified gravity, including the Dvali-Gabadadze-Porrati braneworld scenario, generalized Chaplygin gas, $f(T)$ modified gravity, and Modified Polytropic Cardassian model. Recently released sample of 1598 quasars with X-ray and UV flux measurements in the redshift range of $0.036\leq z \leq 5.1003$, as well as a compilation of 120 intermediate-luminosity radio quasars covering the redshift of $0.46 < z < 2.76$ are respectively used as standard probes at higher redshifts. For all considered modified gravity theories, our results show that there is still some possibility that the standard $��$CDM scenario might not be the best cosmological model preferred by the current quasar observations. In order to improve cosmological constraints, the quasar data are also combined with the latest observations of baryon acoustic oscillations (BAO), which strongly complement the constraints. Finally, we discuss the support given by the data to modified gravity theories, applying different information theoretic techniques like the Akaike Information Criterion (AIC), Bayesian Information Criterion (BIC) and Jensen-Shannon divergence (JSD)., 14 pages, 8 figures, accepted for publication in MNRAS

STUDY DESIGN Retrospective study. OBJECTIVE The aim of this study was to evaluate the long-term clinical and radiographic outcomes of cervical arthroplasty using the ProDisc-C Vivo prosthesis. SUMMARY OF BACKGROUND DATA Previous reports have shown that cervical arthroplasty with ProDisc-C artificial disc has acceptable clinical outcomes at 5-year and 10-year follow-ups. METHODS Clinical and radiographic evaluations, including dynamic flexion-extension lateral images, were performed at baseline and at the 5-year follow-up. RESULTS Twenty-eight patients who underwent single-level ProDisc-C Vivo arthroplasty were followed-up for a mean period of 65 months. The range of motion at the operated level was 8.9 ± 2.3° at baseline and 8.3 ± 4.8° at the final follow-up (p = 0.494). Fourteen of 28 levels (50%) developed heterotopic ossification (HO). According to McAfee's classification, one level was classified as grade I, nine levels as grade II, two levels as grade III, and two levels as grade IV. Only four of 28 levels (14.3%) had severe HO. Among patients with cervical spondylotic myelopathy, mJOA score was 13.9 ± 2.5° at baseline and 15.9 ± 1.0° at the final follow-up (p = 0.001

Fabricating conductive graphene films by assembling graphene oxide (GO) sheets is highly desired for many applications, however a very high temperature around 3000 K is usually required to repair the sp2 structure for traditional thermal annealing. Here, an electric field assisted Joule heating method was developed to repair the sp2 structure in GO at a temperature lower than 1500 oC. The resulting free-standing graphene film shows a high electrical conductivity (~ 1840 S/cm) and high C/O ratio (132), both of which are much higher than those of thermally reduced GO films under the same temperature. These findings provide new possibilities for fabricating high-quality graphene films in an energy-efficient and low-cost manner.

Although investigating metaphors in advertising is gaining in popularity, there are still certain unresolved arguments, such as the interaction between elements of different modalities. This study, composed of three behavioral experiments, aims to identify how verbal anchoring (literal anchoring, metaphor anchoring and unrelated anchoring) influences the processing of pictorial metaphors in advertising, by observing the cognitive and affective indicators, advertising comprehension and advertising likeability. The results showed 1) that metaphors in pictorial modality were recognized more quickly than those in verbal modality, 2) that verbal anchoring facilitated participants ’ comprehending and appreciating of pictorial metaphors and 3) that literally-anchored metaphors with a moderate level of novelty yielded the most favorable cognitive responses. The study not only enriches the existing theoretical framework of multimodal metaphors in advertising, but also proposes an optimal match between pictorial metaphors and verbal elements, for advertisers and manufacturers to design effective multimodal advertisements.

In the breakthrough progress made in the latest experiment Hou et al (2022 Nature 606 507), 2D C 60 polymer was exfoliated from the quasi-hexagonal bulk crystals. Bulk C 60 polymer with quasi-tetragonal phase was found to easily form 1D fullerene structure with C 60 molecules connected by C=C. Inspired by the experiment, we investigate the strain behaviors of 1D and 2D C 60 polymers by first-principles calculations. Some physical properties of these low dimensional C 60 polymers, including structural stability, elastic behavior, band alignment and carrier mobility, are predicted. Compared with fullerene C 60 molecule, 1D and 2D C 60 polymers are metastable. At absolute zero temperature, 1D C 60 bears a uniaxial tensile strain less than 11.5%, and 2D monolayer C 60 withstands a biaxial tensile strain less than 7.5%. At 300 K, ab initio molecular dynamics confirm that they can withstand the strains of 9% and 5%, respectively. Strain engineering can adjust the absolute position of the band edge. In the absence of strain, carrier mobility is predicted to be µ e = 398 and µ h = 322 c m 2 V − 1 s − 1 for 1D C 60 polymer, and μ e , x = 74 / μ e , y = 34 c m 2 V − 1 s − 1 and μ h , x = 646 / μ h , y = 1487 c m 2 V − 1 s − 1 for 2D C 60 polymer. Compared with other carbon based semiconductors, these C 60 polymers exhibit high effective mass, resulting in low mobility.

Swift, non-destructive detection approaches should address the problem of insufficient sensitivity when attempting to obtain and perceive live crab information in low-light environments caused by the crab’s phototaxis. We propose a learning-based low-illumination image enhancer (LigED) for effective enhanced lighting and elimination of darkness in images. The camera response function was combined with the reflectance ground-truth mechanism of image decomposition. Self-attention units were then introduced in the reflectance restoration network to adjust the illumination to avoid visual defects, thus jointly strengthening the adaptability of dark-light enhancement and ability to perceive crab information. Convolutional neural network (CNN)-based detection methods can further enhance the algorithm’s robustness to light and adaptability to different environments, which motivated the development of a scalable lightweight live crab detector (EfficientNet-Det0) utilizing the two-stage compound scaling CNN approach. The lightness order error and natural image quality evaluator based on the proposed methods were 251.26 and 11.60, respectively. The quality of average precision detection increased by 13.84–95.40%. The fastest detection speed of a single image was 91.74/28.41 f·s−1 using a common GPU/CPU, requiring only 15.1 MB of storage, which advocates for the utilization of LigED and EfficientNet-Det0 for the efficient detection of underwater live crabs.

Objective: To investigate and compare the effect of decompression and fusion with internal fixation vs. simple decompression in the treatment of elderly patients with two-segment lumbar spinal stenosis (LSS) in perioperative and postoperative follow-up periods. Methods: Twenty-eight elderly patients with two-segment LSS admitted in Baoding First Hospital between Mar. 2017 and Jan. 2018 were retrospectively analyzed. Fifteen patients who underwent simple decompression were included in the simple decompression group, and 13 who underwent decompression and fusion with internal fixation were included in the decompression-fixation group. The general data and perioperative conditions including wound complications, operation time, blood loss, and VAS (legs) and JOA score were analyzed and compared between the two groups. Results: There was no significant difference in postoperative leg pain (VAS) between the two groups, and a statistically significant difference in JOA score was found between the two groups one month after the operation. The operation time, length of stay, and blood loss in the decompression-fixation group were significantly different from those in the simple decompression group and no significant difference in wound complications was observed between the two groups. Conclusion: There is no significant difference in leg pain relief in elderly patients with two-segment LSS when treated with decompression and fusion with internal fixation or simple decompression. Simple decompression is associated with less intraoperative injuries, better postoperative functional recovery, and reduced hospital stay. doi: https://doi.org/10.12669/pjms.37.1.2287 How to cite this:Tu P, Cao S, Jiang C, Yan CC. A comparative study of Lumbar Decompression and Fusion with Internal Fixation versus Simple Decompression in elderly patients with two-segment Lumbar Spinal Stenosis. Pak J Med Sci. 2021;37(1):256-260. doi: https://doi.org/10.12669/pjms.37.1.2287 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Background: Microtubule Targeting Agents (MTAs) represent the most successful anticancer drugs for cancer chemotherapy. Through interfering with the tubulin polymerization and depolymerization dynamics, MTAs influence intracellular transport and cell signal pathways, inhibit cell mitosis and cell proliferation, and induce cell apoptosis and death. The tubulin maytansine site binding agents are natural or nature-derived products that represent one type of the MTAs that inhibit tubulin polymerization and exhibit potent antitumor activity both in vitro and in vivo. They are used as Antibody-Drug Conjugates (ADCs) in cancer chemotherapy. Methods: Using SciFinder® as a tool, the publications about maytansine, its derivatives, maytansine binding site, maytansine site binding agents and their applications as MTAs for cancer therapy were surveyed with an exclusion on those published as patents. The latest progresses in clinical trials were obtained from the clinical trial web. Results: This article presents an introduction about MTAs, maytansine, maytansine binding site and its ligands, the applications of these ligands as MTAs and ADCs in cancer therapy. Conclusion: The maytansine site binding agents are powerful MTAs for cancer chemotherapy. The maytansine site ligands-based ADCs are used in clinic or under clinical trials as cancer targeted therapy to improve their selectivity and to reduce their side effects. Further improvements in the delivery efficiency of the ADCs will benefit the patients in cancer targeted therapy.

RNA-binding proteins (RBPs) are significantly dysregulated in glioma. In this study, we demonstrated the upregulation of Nuclear cap-binding subunit 3 (NCBP3) in glioma tissues and cells. Further, knockdown of NCBP3 inhibited the malignant progression of glioma. NCBP3 directly bound to small nucleolar RNA host gene 6 (SNHG6) and stabilized SNHG6 expression. In contrast, the gastrulation brain homeobox 2 (GBX2) transcription factor was downregulated in glioma tissues and cells. SNHG6 inhibited GBX2 transcription by mediating the H3K27me3 modification induced by polycomb repressive complex 2 (PRC2). Moreover, GBX2 decreased the promoter activities and downregulated the expression of the flotillin protein family 1 (FLOT1) oncogene. In conclusion, NCBP3/SNHG6 inhibits GBX2 transcription in a PRC2-dependent manner to facilitate the malignant progression of gliomas.

The cosmic curvature, a fundamental parameter for cosmology could hold deep clues to inflation and cosmic origins. We propose an improved model-independent method to constrain the cosmic curvature by combining the constructed Hubble diagram of high-redshift quasars with galactic-scale strong lensing systems expected to be seen by the forthcoming LSST survey. More specifically, the most recent quasar data are used as a new type of standard candles in the range $0.036, Comment: 7 figures, 11 pages, accepted for publication in MNRAS

Based on the technology of RS & GIS and the remote sensing images of Jixi City in 1993, 2003 and 2015, this study analyzes quantitatively the temporal and spatial evolution characters of landscape pattern in the downtown area of Jixi City in China in the past 22 years. The research results show that the area of mine land, farmland and construction land increased greatly from 1993 to 2015. As an important part of the urban natural ecosystem, the area of water area, forest and grassland are also decreasing year by year. In the past 22 years, due to the impact of human activities such as coal resources development, the coal mine land in the central urban area is distributed in the agricultural farming area and the edge zone with different landscape types. On the whole, the fragmentation degree and diversity of regional landscape are increasing, and human activities have a significant impact on the urban landscape pattern of Jixi City. This paper attempts to explore the general law of landscape pattern change under the influence of human activities in mining cities and to provide a reference for urban land use planning and scientific decision-making of relevant government departments.

In this work, well-ordered platinum (Pt) nanocubes (NCs), with precise control on the size and the spatial arrangement, are synthesized from a microemulsion overgrowth in a block copolymer (BC) nanotemplate. The nanovials on this self-assembled BC template serve as microreactors for the reduction of the HCl/H

Along with intensification of global warming, severe desertification has already impaired human sustainable development. In a near-future greenhouse world, the total area of desert will increase, and new types of desert may emerge. During the “greenhouse” Cretaceous, conventional large paleo-ergs developed in broad topographic basins, and many possible ergs developed in small-scale intermountain basins, which are unusual in near-modern times and less studied. A comprehensive study of their sedimentary architecture and mechanisms would refine our interpretation of desertification in a near-future “greenhouse” world. The Xinjiang Basin is a typical small-scale intermountain basin in Southeast China that formed >300 m of successive aeolian deposits during the early Late Cretaceous. In this study, we applied detailed facies and architecture analyses to the Tangbian Formation (K2t) in 16 outcrops throughout the Xinjiang Basin and reconstructed a three-dimensional sedimentary model for the intermountain ergs. We confirmed that the Tangbian Formation formed in a typical intermountain paleo-erg and summarized in detail the differences in sedimentary architecture between intermountain ergs and broad topographic ergs. We noticed that the “greenhouse” state during the Late Cretaceous seems to have been suitable for the development of ergs in intermountain basins due to the hot, arid climate conditions and penetrating winds with sufficient transport capacity. Therefore, we suggest that in addition to the ongoing expansion of broad topographic ergs, the emergence and development of intermountain ergs in a near-future “greenhouse” world would also contribute to global desert expansion and massive desertification.

Using evoked response potentials, we investigated the implicit detection of incongruity during target-source matching in pictorial metaphors of Chinese advertising. Participants saw an image of a product (the target in a visual metaphorical relationship), and then made a same-different judgment in response to a second image (the source in a visual metaphorical relationship) which was (in)congruous to the first image in terms of shape and/or function. We collected behavioral (button-press reaction time and accuracy), and neural (N270, delta and theta band activity) measures. The time-frequency analysis showed faster processing of incongruous visual information. Moreover, shape and conceptual incongruity were associated with increased N270 amplitude as well as delta (1-3 Hz) and theta (4-8 Hz) band power. Noticeably, compared with conceptual incongruity, shape incongruity evoked a larger N270 amplitude and stronger delta and theta band oscillation. In addition, the average topographical analysis revealed a frontal and central distribution of the power activity. The analysis of attitudes towards the advertising metaphor pictures also proved the supportive role played by incongruity. In conclusion, incongruity facilitates target-source matching in pictorial metaphors of Chinese advertising. The findings obtained from the study are important to metaphor designs of advertising pictures. peerReviewed

We built optical and spectral analysis instruments of ultrasensitive nonlinear optical microscopies (NLOMs), in which coherent anti-Stokes Raman scattering (CARS), second harmonic generation (SHG),...

Two dimensional (2D) organic-inorganic hybrid perovskites have attracted great interest due to their tunable band gap and structural stability. In this study, biaxial strain behavior and carrier mobility of monolayers (C4H9NH3)2GeI4 and (C4H9NH3)2SnI4 are investigated by first principles calculations. (C4H9NH3)2GeI4 and (C4H9NH3)2SnI4 still retain their structural stability at e = 13% and e = 15%, respectively. Ab initio molecular dynamics (AIMD) simulation has confirmed that the system at 300 K is still thermodynamically stable at a biaxial strain of e = 8%. The band gaps of (C4H9NH3)2GeI4 and (C4H9NH3)2SnI4 calculated from the HSE06 functional are increased from 2.427 and 1.953 eV at zero strain to 3.002 and 2.626 eV at e = 8%. Deformation potential (DP) models based on longitudinal acoustic phonon (LAP) and optical phonon (OP) scattering are used to investigate mobility. The mobility of (C4H9NH3)2GeI4 is lower than that of (C4H9NH3)2SnI4. It is mainly determined by the scattering from OP with lower energy and decreases sharply with an increase in biaxial strain. Compared with Pb based perovskites, (C4H9NH3)2SnI4 exhibits high carrier mobility and thermodynamic stability.

First principles calculations are performed to predict phonon-limited carrier mobility for a novel graphene-like semiconductor with BC6N stoichiometry. First, the electron–phonon interaction matrix element (EPIME) from the standard Wannier and polar Wannier interpolation schemes is used to investigate mobility. After considering the polarization, carrier mobility is greatly reduced, so polar optical phonon (POP) scattering plays an important role. At 300 K, the electron mobility for the most stable BC6N–B is predicted to be μx = 4.51 × 102–8.37 × 102 and μy = 8.35 × 102–1.22 × 103 cm2 V−1 s−1, while the hole mobility is estimated to be μx = 4.79 × 102–8.65 × 102 and μy = 9.19 × 102–1.28 × 103 cm2 V−1 s−1. Then, the longitudinal acoustic phonon deformation potential theory (LAP-DPT) is adopted to calculate the mobility, which leads to an overestimation for carrier mobility in polar semiconductors. Furthermore, the semiempirical model based on the POP scattering is also used to investigate the mobility. It is confirmed that the intrinsic mobility for BC6N is mainly determined by the Frohlich interaction. The investigation provides a deep understanding of carrier transport properties. It is revealed that B and N co-doped graphene may become a promising material for application in nanoelectronic devices due to the excellent mechanical behavior, moderate direct band gap and high carrier mobility.

International audience; The oxygen-free alkane direct dehydrogenation (DDH) is a greener, safer, and more selective alternative to oxygen co-fed conditions to produce olefins. Carbon-based catalysts have significantly boosted this branch of catalysis by providing cheaper, robust, durable, and more environmentally friendly single-phase materials as valuable substitutes of a variety of alkaline- or alkaline earth-promoted transition metal oxides. In particular, nanodiamonds (NDs) rank among the most effective and selective metal-free systems investigated so far for the alkane-to-alkene conversion under either oxidative or direct dehydrogenation conditions. Although important structural/compositional/activity relationships for this class of sp2/sp3 C-hybrids have already been unveiled for the exothermic oxidative dehydrogenation (ODH) process, many issues still remain to be addressed for the more challenging oxygen-free direct dehydrogenation process. In particular, the mechanism and nature of active sites in carbon catalysts employed for the alkane steam-free DDH still remain a controversial matter of debate because of the lack of studies under harsher operative conditions typically required by this endothermic process. Here, we report on the chemico-physical and morphological properties of nanodiamond samples before and after their use as catalysts in the model ethylbenzene-to-styrene dehydrogenation using oxygen and oxygen-free conditions. The combination of the catalytic outcomes with the extensive characterization of these metal-free systems led us to speculate on the nature of oxidized carbons as catalytically active sites in the DDH process. Density functional theory (DFT) calculations have finally been used to corroborate our hypotheses, providing support to the role of ortho-quinone (oQ) groups at the edge of cubic-sp3 NDs as the oxidized carbon source (active sites) for DDH.

Einstein's theory of general relativity (GR) has been precisely tested on solar system scales, but extragalactic tests are still poorly performed. In this work, we use a newly compiled sample of galaxy-scale strong gravitational lenses to test the validity of GR on kiloparsec scales. In order to solve the circularity problem caused by the preassumption of a specific cosmological model based on GR, we employ the distance sum rule in the Friedmann-Lema\^{\i}tre-Robertson-Walker metric to directly estimate the parameterized post-Newtonian (PPN) parameter $\gamma_{\rm PPN}$ and the cosmic curvature $\Omega_k$ by combining observations of strong lensing and Type Ia supernovae. This is the first simultaneous measurement of $\gamma_{\rm PPN}$ and $\Omega_k$ without any assumptions about the contents of the universe or the theory of gravity. Our results show that $\gamma_{\rm PPN}=1.11^{+0.11}_{-0.09}$ and $\Omega_{k}=0.48^{+1.09}_{-0.71}$, indicating a strong degeneracy between the two quantities. The measured $\gamma_{\rm PPN}$, which is consistent with the prediction of 1 from GR, provides a precise extragalactic test of GR with a fractional accuracy better than 9.0\%. If a prior of the spatial flatness (i.e., $\Omega_{k}=0$) is adopted, the PPN parameter constraint can be further improved to $\gamma_{\rm PPN}=1.07^{+0.07}_{-0.07}$, representing a precision of 6.5\%. On the other hand, in the framework of GR (i.e., $\gamma_{\rm PPN}=1$), our results are still marginally compatible with zero curvature ($\Omega_k=-0.12^{+0.48}_{-0.36}$), supporting no significant deviation from a flat universe., Comment: Updated to match the published version in ApJ Letters

Effective and accurate parameter identification, especially the identification of load torque, is one of the key factors to improve the control performance of the robot servo system. Sliding mode observer (SMO) has always been a common method for identifying load torque due to its advantages of simple implementation, strong robustness, and fast response. However, due to the discontinuity of the SMO switching function, the system will generate high-frequency chattering, which will reduce the accuracy of load torque identification and affect system performance. In this paper, an adaptive parameter identification method based on an improved sliding mode observer is proposed. A continuous deformation mode of saturation function based on boundary variation is proposed as the switching function to alleviate the chattering phenomenon. Meanwhile, the relationship between the sliding mode gain and the feedback gain of proposed SMO is defined so that it can be selected properly to improve the accuracy of identification, and the radial basis function neural network (RBFNN) is used to adaptively tune the boundary layer gain according to the speed change. Moreover, considering that the identification result of the load torque is related to the moment of inertia and the mismatch of the inertia will cause identification errors, the variable period integration method is proposed to identify the inertia and redefine the calculation period of the load torque and inertia. The effectiveness and superiority of the proposed method are verified by simulation experiments. Experimental results demonstrate that the improved SMO combines observer gain coefficient tuning and inertia matching can smoothly and accurately estimate the value of load torque, which is an adaptive identification method worthy of reference for robot servo system.

Although the spatial curvature has been precisely determined via the cosmic microwave background (CMB) observation by Planck satellite, it still suffers from the well-known cosmic curvature tension. As a standard siren, gravitational waves (GWs) from binary neutron star mergers provide a direct way to measure the luminosity distance. In addition, the accelerating expansion of the universe may cause an additional phase shift in the gravitational waveform, which allows us to measure the acceleration parameter. This measurement provides an important opportunity to determine the curvature parameter $\Omega_k$ in the GW domain based on the combination of two different observables for the same objects at high redshifts. In this study, we investigate how such an idea could be implemented with future generation of space-based DECi-hertz Interferometer Gravitational-wave Observatory (DECIGO) in the framework of two model-independent methods. Our results show that DECIGO could provide a reliable and stringent constraint on the cosmic curvature at a precision of $\Delta\Omega_k$=0.12, which is comparable to existing results based on different electromagnetic data. Our constraints are more stringent than the traditional electromagnetic method from the Pantheon SNe Ia sample, which shows no evidence for the deviation from the flat universe at $z\sim 2.3$. More importantly, with our model-independent method, such a second-generation space-based GW detector would also be able to explore the possible evolution $\Omega_k$ with redshifts, through direct measurements of cosmic curvature at different redshifts ($z\sim 5$). Such a model-independent $\Omega_k$ reconstruction to the distance past can become a milestone in gravitational-wave cosmology., Comment: 10 pages, 6 figures, accepted for publication in ApJ

In this Letter, we present a new idea of probing the distribution of dark matter exhibiting elastic and velocity-independent self-interactions. These interactions might be revealed in multiple measurements of strongly lensed gravitational waves, which can be observationally explored to determine the strength of self-scatterings. Specifically, each individual galactic-scale strong-lensing system whose source is a coalescing compact binary emitting gravitational waves will provide a model-independent measurement of the shear viscosity of dark matter along the line of sight. These individual measurements could be a probe of large-scale distribution of dark matter and its properties. Our results indicate that with 10-1000 strongly lensed gravitational waves from ET and DECIGO, robust constraints on the large-scale distribution of self-interacting dark matter might be produced. More stringent limits on the dark matter scattering cross-section per unit mass ($\sigma_{\chi}/m_{\chi}$) relevant to galaxy and cluster scales are also expected, compared with the conservative estimates obtained in the electromagnetic domain. Finally, we discuss the effectiveness of our method in the context of self-interacting dark matter particle physics., Comment: 6 pages, 4 figures, accepted for publication in Astronomy & Astrophysics Letters

The waveform in the time domain, spectrum in the frequency domain, and topography in the space domain of component(s) of interest are the fundamental indices in neuroscience research. Despite the application of time–frequency analysis (TFA) to extract the temporal and spectral characteristics of non-phase-locked component (NPLC) of interest simultaneously, the statistical results are not always expectedly satisfying, in that the spatial information is not considered. Complex Morlet wavelet transform is widely applied to TFA of event-related-potential (ERP) data, and mother wavelet (which should be firstly defined by center frequency and bandwidth (CFBW) before using the method to TFA of ERP data) influences the time–frequency results. In this study, an optimal set of CFBW was firstly selected from the number sets of CFBW, to further analyze for TFA of the ERP data in a cognitive experiment paradigm of emotion (Anger and Neutral) and task (Go and Nogo). Then tensor decomposition algorithm was introduced to investigate the NPLC of interest from the fourth-order tensor. Compared with the TFA results which only revealed a significant difference between Go and Nogo task condition, the tensor-based analysis showed significant interaction effect between emotion and task. Moreover, significant differences were found in both emotion and task conditions through tensor decomposition. In addition, the statistical results of TFA would be affected by the selected region of interest (ROI), whereas those of the proposed method were not subject to ROI. Hence, this study demonstrated that tensor decomposition method was effective in extracting NPLC, by considering spatial information simultaneously as the potential to explore the brain mechanisms related to experimental design.

Shennongjia is one of the most important ecological function areas and ecologically vulnerable zones in the world. With the rapid development of social economies, especially tourism, the ecological environment of Shennongjia has experienced profound changes. Exploring the characteristics and changing trends of ecological environment in Shennongjia will help to analyze the causes of the damage to the ecological environment, and build a vulnerability analysis framework with multi-scale, multi-element, multi-flow, and multi-circulation characteristics, which provides an effective research paradigm and analysis tool for the study of regional ecological vulnerability. With the support of RS and GIS technology, this study uses spatial principal component analysis (SPCA) and the vulnerability scoring diagram (VSD) model to comprehensively and quantitatively analyze the spatial and temporal evolution characteristics and driving forces of ecological vulnerability in Shennongjia from 1996 to 2018. The VSD model was selected to decompose the vulnerability into three components of "exposure-sensitivity-adaptation", and 16 indicators were selected to construct an ecological vulnerability evaluation system in Shennongjia, and the evaluation data were organized in a progressive and detailed way. (1) During the study period, the overall ecological vulnerability of Shennongjia is in a mild vulnerability level, exhibiting differentiation characteristics of high in the northeast and low in the southwest. High vulnerability zones are mainly distributed in the main towns and roads. (2) The risk of ecological vulnerability of the entire region presents the characteristics of continuous decline. (3) Land-use types, population density, and vegetation coverage are the main factors driving the evolution of ecological vulnerability. (4) A high level of coupling coordination exists between ecological vulnerability and landscape patterns. Analyses of the ecological vulnerability of Shennongjia shows that the entire region is in a mild vulnerability level. The extreme vulnerability risk of the ecological environment shows polarization. The evolution of ecological environment in Shennongjia is the result of the interaction between human activities and natural environment. This study offers an effective way to assess ecological vulnerability and provides some strategies and guidance for improving ecological security.

Inorganic halide perovskites have attracted interest due to their high efficiency and low cost. Considering the uncertainty of experimental measurements, it was important to predict the upper limit of carrier mobility. In this study, the ab initio Boltzmann transport equation, including all electron–phonon interactions, was used to accurately predict the mobilities of CsPbI3, CsSnI3, CsPbBr3, and CsSnBr3. Using the iterative Boltzmann transport equation (IBTE), the calculated mobility for CsPbI3 is µ e = 512/µ h = 379 cm2 V−1 s−1, and Sn-based perovskite exhibited high hole mobility. The longitudinal optical phonons associated with the stretching between halogen anions and divalent metal cations were revealed to be the dominant scattering source for the carriers. Furthermore, the effect of biaxial strain on mobility was investigated. We observed that biaxial compressive strain could improve the mobility of CsPbI3 and CsPbBr3. Surprisingly, under a compressive strain of − 2 % , the mobilities of CsPbI3 using IBTE approach were improved to µ e = 1176/µ h = 936 cm2 V−1 s−1. It was revealed that the compressive strain could decrease the effective mass of CsPbI3 and CsPbBr3.

In this paper, we use a newly compiled sample of ultra-compact structure in radio quasars and strong gravitational lensing systems with quasars acting as background sources to constrain six spatially flat and non-flat cosmological models ($\Lambda$CDM, PEDE and DGP). These two sets of quasar data (the time-delay measurements of six strong lensing systems and 120 intermediate-luminosity quasars calibrated as standard rulers) could break the degeneracy between cosmological parameters ($H_0$, $\Omega_m$ and $\Omega_k$) and therefore provide more stringent cosmological constraints for the six cosmological models we study. A joint analysis of the quasar sample provides model-independent estimations of the Hubble constant $H_0$, which is strongly consistent with that derived from the local distance ladder by SH0ES collaboration in the $\Lambda$CDM and PEDE model. However, in the framework of a DGP cosmology (especially for the flat universe), the measured Hubble constant is in good agreement with that derived from the the recent Planck 2018 results. In addition, our results show that zero spatial curvature is supported by the current lensed and unlensed quasar observations and there is no significant deviation from a flat universe. For most of cosmological model we study (the flat $\Lambda$CDM, non-flat $\Lambda$CDM, flat PEDE, and non-flat PEDE models), the derived matter density parameter is completely consistent with $\Omega_m\sim 0.30$ in all the data sets, as expected by the latest cosmological observations. Finally, according to the the statistical criteria DIC, although the joint constraints provide substantial observational support to the flat PEDE model, they do not rule out dark energy being a cosmological constant and non-flat spatial hypersurfaces., Comment: 11 pages, 5 figures, accepted for publication in A&A

Observations of galaxy-scale strong gravitational lensing (SGL) systems have enabled unique tests of nonlinear departures from general relativity (GR) on the galactic and supergalactic scales. One of the most important cases of such tests is constraints on the gravitational slip between two scalar gravitational potentials. In this paper, we use a newly compiled sample of strong gravitational lenses to test the validity of GR, focusing on the screening effects on the apparent positions of lensed sources relative to the GR predictions. This is the first simultaneous measurement of the Post-Newtonian (PN) parameter ($\gamma_{PN}$) and the screening radius ($\Lambda$) without any assumptions about the contents of the Universe. Our results suggest that the measured PPN is marginally consistent with GR ($\gamma_{PN}=1$) with increasing screening radius ($\Lambda = 10-300 $kpc), although the choice of lens models may have a significant influence on the final measurements. Based on a well-defined sample of 5000 simulated strong lenses from the forthcoming LSST, our methodology will provide a strong extragalactic test of GR with an accuracy of 0.5\%, assessed up to scales of $\Lambda \sim 300$ kpc. For the current and future observations of available SGL systems, there is no noticeable evidence indicating some specific cutoff scales on kpc-Mpc scales, beyond which new gravitational degrees of freedom are expressed., Comment: 14 pages, 9 figures, accepted for publication in ApJ

Objectives: To investigate and analyze the effect of percutaneous minimally invasive pedicle screw internal fixation in the treatment of thoracolumbar vertebral fractures and its impact on quality of life. Methods: Fifty patients with thoracolumbar vertebral fracture admitted to our hospital from January 2015 to December 2018 were selected and divided into two groups according to different treatment regimens. The observation group was treated with minimally invasive percutaneous pedicle screw internal fixation, while the control group was treated with traditional posterior approach open pedicle screw internal fixation. The surgery time, incision length, intraoperative blood loss, postoperative drainage, hospitalization time, ambulation time, fracture healing time and postoperative VAS scores were compared between the two groups. In addition, the cobb angle, the sagittal plane index, and the anterior vertebral height were compared between the two groups before and after surgery, as were the Oswestry Disability Index (ODI) at 1d, 3 months, and 6 months postoperatively. Results: The surgery time, incision length, postoperative pain level, postoperative drainage and intraoperative blood loss of the observation group were less than those of the control group (P

It has been a half-decade since the first direct detection of gravitational waves, which signifies the coming of the era of the gravitational-wave astronomy and gravitational-wave cosmology. The increasing number of the detected gravitational-wave events has revealed the promising capability of constraining various aspects of cosmology, astronomy, and gravity. Due to the limited space in this review article, we will briefly summarize the recent progress over the past five years, but with a special focus on some of our own work for the Key Project ``Physics associated with the gravitational waves'' supported by the National Natural Science Foundation of China. In particular, (1) we have presented the mechanism of the gravitational-wave production during some physical processes of the early Universe, such as inflation, preheating and phase transition, and the cosmological implications of gravitational-wave measurements; (2) we have put constraints on the neutron star maximum mass according to GW170817 observations; (3) we have developed a numerical relativity algorithm based on the finite element method and a waveform model for the binary black hole coalescence along an eccentric orbit., v1, 93 pages, 18 figures, prepared as a status review of project report for Sci. China Phys. Mech. Astron.; v2, 95 pages, minor revision, references added, accepted for publication in Sci. China Phys. Mech. Astron; v3, to match the published version

In this work, we consider the burst signal of the dark photon, the hypothetical vector boson of the $U(1)_B$ or $U(1)_{B-L}$ gauge group, generated by a compact binary star system. The absence of the signal in the laser interferometer puts bounds on the coupling constant $\epsilon$ to the ordinary matter. It turns out that if the dark photon is massless, $\epsilon^2$ is on the order of $10^{-37}-10^{-33}$ at most; in the massive case, the upper bound of $\epsilon^2$ is about $10^{-38}-10^{-31}$ in the mass range from $10^{-19}$ eV to $10^{-11}$ eV. These are the first bounds derived from the interferometer observations independent of the assumption of dark photons being dark matter., Comment: 11 pages, 2 figures. Modified according to Referee's suggestions