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Molecular dynamics (MD) is an extremely powerful, highly effective, and widely used approach to understanding the nature of chemical processes in atomic details for proteins. The accuracy of results from MD simulations is highly dependent on force fields. Currently, molecular mechanical (MM) force fields are mainly utilized in MD simulations because of their low computational cost. Quantum mechanical (QM) calculation has high accuracy, but it is exceedingly time consuming for protein simulations. Machine learning (ML) provides the capability for generating accurate potential at the QM level without increasing much computational effort for specific systems that can be studied at the QM level. However, the construction of general machine learned force fields, needed for broad applications and large and complex systems, is still challenging. Here, general and transferable neural network (NN) force fields based on CHARMM force fields, named CHARMM-NN, are constructed for proteins by training NN models on 27 fragments partitioned from the residue-based systematic molecular fragmentation (rSMF) method. The NN for each fragment is based on atom types and uses new input features that are similar to MM inputs, including bonds, angles, dihedrals, and non-bonded terms, which enhance the compatibility of CHARMM-NN to MM MD and enable the implementation of CHARMM-NN force fields in different MD programs. While the main part of the energy of the protein is based on rSMF and NN, the nonbonded interactions between the fragments and with water are taken from the CHARMM force field through mechanical embedding. The validations of the method for dipeptides on geometric data, relative potential energies, and structural reorganization energies demonstrate that the CHARMM-NN local minima on the potential energy surface are very accurate approximations to QM, showing the success of CHARMM-NN for bonded interactions. However, the MD simulations on peptides and proteins indicate that more accurate methods to represent protein–water interactions in fragments and non-bonded interactions between fragments should be considered in the future improvement of CHARMM-NN, which can increase the accuracy of approximation beyond the current mechanical embedding QM/MM level. [ABSTRACT FROM AUTHOR]

Blockchain, essentially a distributed and immutable database, has emerged as a potential solution to governance problems of accountability, transparency, and trust in the construction industry. In terms of construction quality management (CQM) applications, previous works mainly took a technical perspective, and little is known about the potential of blockchain-based governance for quality opportunism. Moreover, we have seen very few successful blockchain implementations in construction practices. Stakeholders meet the trade-off between potential benefits and risks in blockchain adoption decisions. Previous works mainly focused on barrier analysis, neglecting the dynamic interactions of stakeholders' strategic behaviors on adopting blockchains. Against this backdrop, this research aims to systematically analyze blockchain impacts on CQM from a governance perspective and then investigate the owner and the main contractors' strategic behaviors (e.g., adopting blockchains in CQM or not). The agency theory was used as the theoretical lens to examine how blockchain curbs contractors' quality opportunistic behaviors as a governance mechanism. An evolutionary game theory model was developed to simulate adoption decision interactions between the owner and the main contractor. Finally, policy suggestions were highlighted for policymakers. This research could be one of the first studies examining blockchain potential to CQM from an opportunism governance perspective. Such discussions could inspire more discussions on blockchain-based governance and broaden researchers' and practitioners' understandings of blockchain impacts. The proposed policy suggestions from the equilibrium analysis could facilitate blockchain diffusion in the construction industry. [ABSTRACT FROM AUTHOR]

Accurately delineating the connection between short nucleolar RNA (snoRNA) and disease is crucial for advancing disease detection and treatment. While traditional biological experimental methods are effective, they are labor-intensive, costly and lack scalability. With the ongoing progress in computer technology, an increasing number of deep learning techniques are being employed to predict snoRNA–disease associations. Nevertheless, the majority of these methods are black-box models, lacking interpretability and the capability to elucidate the snoRNA–disease association mechanism. In this study, we introduce IGCNSDA, an innovative and interpretable graph convolutional network (GCN) approach tailored for the efficient inference of snoRNA–disease associations. IGCNSDA leverages the GCN framework to extract node feature representations of snoRNAs and diseases from the bipartite snoRNA-disease graph. SnoRNAs with high similarity are more likely to be linked to analogous diseases, and vice versa. To facilitate this process, we introduce a subgraph generation algorithm that effectively groups similar snoRNAs and their associated diseases into cohesive subgraphs. Subsequently, we aggregate information from neighboring nodes within these subgraphs, iteratively updating the embeddings of snoRNAs and diseases. The experimental results demonstrate that IGCNSDA outperforms the most recent, highly relevant methods. Additionally, our interpretability analysis provides compelling evidence that IGCNSDA adeptly captures the underlying similarity between snoRNAs and diseases, thus affording researchers enhanced insights into the snoRNA–disease association mechanism. Furthermore, we present illustrative case studies that demonstrate the utility of IGCNSDA as a valuable tool for efficiently predicting potential snoRNA–disease associations. The dataset and source code for IGCNSDA are openly accessible at: https://github.com/altriavin/IGCNSDA. [ABSTRACT FROM AUTHOR]

Leveraging data from various modalities to enhance multimodal segmentation tasks is a well-regarded approach. Recently, efforts have been made to incorporate an array of modalities, including depth and thermal imaging. Nevertheless, the effective amalgamation of cross-modal interactions remains a challenge, given the unique traits each modality presents. In our current research, we introduce the semantic guidance fusion network (SGFN), which is an innovative cross-modal fusion network adept at integrating a diverse set of modalities. Particularly, the SGFN features a semantic guidance module (SGM) engineered to boost bi-modal feature extraction. It encompasses a learnable semantic guidance convolution (SGC) designed to merge intensity and gradient data from disparate modalities. Comprehensive experiments carried out on the NYU Depth V2, SUN-RGBD, Cityscapes, MFNet, and ZJU datasets underscore both the superior performance and generalization ability of the SGFN compared to the current leading models. Moreover, when tested on the DELIVER dataset, the efficiency of our bi-modal SGFN displayed a mIoU that is comparable to the hitherto leading model, CMNEXT. [ABSTRACT FROM AUTHOR]

The application of liquid metal in a microfluidic system enables the fabrication of highly integrated on-chip electroosmotic micropumps (EOPs). In this work, a low-voltage driveable integrated parallel EOP cluster drive system is proposed. This system consists of two layers, a branch-channel layer and a trunk-channel layer. The lower branch-channel layer contains separate parallel pumping channels and a pair of comb liquid metal electrodes. The separated branch channels are connected together through the trunk channels in the upper layer. With this structural arrangement, the parallel micropumps form an integrated micropump cluster for larger pumping capacity. The distance between the pumping channel and the electrode next to it is controlled to 20 μm. To guide the pump design, parametric studies are performed and fully discussed. According to the experimental results, the micropump cluster can be driven at a low voltage of 0.5 V, and the flow rate reaches 274 nL min−1 at 5 V. In addition, the paper finally proposes an electrode protection strategy and an integrated pump-valve drive system which is expected to solve the shortcoming of electroosmotic pumps in terms of long-time storage and driving. [ABSTRACT FROM AUTHOR]

Many practical industrial processes require gas–liquid mass transfer in highly viscous liquids, and liquid viscosity affects bubble characteristics and gas–liquid mass transfer. The current study investigated the effects of liquid viscosity on bubble dynamics and gas–liquid mass transfer via shadow imaging and dynamic oxygen dissolution methods, and the influence of fluid viscosity on the hydrodynamic effect when using a wire mesh-coupled solid particles method. The coupling strategy was associated with a bubble size regulation effect, with greater viscosity increasing the gas–liquid interface area by 27%–55% compared with unreinforced gas–liquid flow, which was superior to embedded wire mesh and added solid particles methods. Increased viscosity weakened the mass transfer enhancement effect of the coupling method, but the coupling method still effectively enhanced the gas–liquid mass transfer process, increasing the volumetric mass transfer coefficient (KLa) by 80%–130% compared to non-enhanced gas–liquid flow. Novel empirical KLa correlation equations were developed to predict the effects of the coupling method on gas–liquid mass transfer processes, and those equations exhibited good reliability and predictive capacity. [ABSTRACT FROM AUTHOR]

This paper is concerned with the set-membership filtering problem for the two-dimensional shift-varying systems subject to the stochastic communication protocol and uniform quantization effects. To prevent the data transmission from collisions, only one sensor can transmit the measured information to the filter at each sampling shift instant, and the selected sensor is determined by the scheduling strategy of the stochastic communication protocol. On the contrary, the uniform quantization mechanism has been employed to mitigate the influence of quantization error on filtering performance. Incorporating the stochastic communication protocol and uniform quantization mechanism, this paper proposes a set-membership filter design framework for the two-dimensional shift-varying systems with unknown-but-bounded noises. Sufficient conditions are derived for the existence of desired set-membership filter by utilizing double mathematical induction, such that the estimation error resides within the ellipsoidal set. Moreover, the optimal filtering algorithm is given by minimizing the ellipsoidal constraints. Finally, several examples are provided to illustrate the effectiveness of the proposed filter design algorithm. [ABSTRACT FROM AUTHOR]

A two-layer control strategy for the participation of multiple battery energy storage systems in the secondary frequency regulation of the grid is proposed to address the frequency fluctuation problem caused by the power dynamic imbalance between the power system and load when a large number of new energy sources are connected to the grid. A comprehensive allocation model based on area regulation requirement (ARR) signals and area control error (ACE) signals is proposed to obtain the total output of the secondary frequency modulation (FM) demand with a higher degree of adaptation when the FM units respond to the automatic generation control command, and the total output is reasonably allocated to each FM unit by using the two-layer control. Considering the dynamic fluctuation of the grid frequency, the fluctuation is dynamically suppressed in real-time by applying model predictive control to successfully forecast the frequency deviation while realizing the deviation-free correction in the frequency dynamic correction layer. The optimal power distribution of FM units based on the distributed control concept, as well as the power depth of each unit, are coordinated in the equalization control layer while keeping a decent battery charge level. Finally, in Matlab/Simulink, the proposed control approach is simulated and validated. The findings show that the suggested control approach can suppress frequency difference fluctuation, keep the battery charged, and reduce the unit's FM loss. [ABSTRACT FROM AUTHOR]

Report here is a Rh‐catalyzed [4+3]/[4+1] cycloaddition of diene‐vinylcyclopropanes (diene‐VCPs) and carbon monoxide to access compounds with angular 5/7/5 tricyclic skeleton found in natural products. The reaction has broad scope and further transformation of the [4+3]/[4+1] cycloadduct was also investigated. How this [4+3]/[4+1] reaction occurs and why its competing [4+3] reaction is disfavored have been investigated computationally. [ABSTRACT FROM AUTHOR]

Background: Protein phosphatases type 2C (PP2C) are heavily involved in plant growth and development, hormone-related signaling pathways and the response of various biotic and abiotic stresses. However, a comprehensive report identifying the genome-scale of PP2C gene family in ginger is yet to be published. Results: In this study, 97 ZoPP2C genes were identified based on the ginger genome. These genes were classified into 15 branches (A-O) according to the phylogenetic analysis and distributed unevenly on 11 ginger chromosomes. The proteins mainly functioned in the nucleus. Similar motif patterns and exon/intron arrangement structures were identified in the same subfamily of ZoPP2Cs. Collinearity analysis indicated that ZoPP2Cs had 33 pairs of fragment duplicated events uniformly distributed on the corresponding chromosomes. Furthermore, ZoPP2Cs showed greater evolutionary proximity to banana's PP2Cs. The forecast of cis-regulatory elements and transcription factor binding sites demonstrated that ZoPP2Cs participate in ginger growth, development, and responses to hormones and stresses. ZoERFs have plenty of binding sites of ZoPP2Cs, suggesting a potential synergistic contribution between ZoERFs and ZoPP2Cs towards regulating growth/development and adverse conditions. The protein–protein interaction network displayed that five ZoPP2Cs (9/23/26/49/92) proteins have robust interaction relationship and potential function as hub proteins. Furthermore, the RNA-Seq and qRT-PCR analyses have shown that ZoPP2Cs exhibit various expression patterns during ginger maturation and responses to environmental stresses such as chilling, drought, flooding, salt, and Fusarium solani. Notably, exogenous application of melatonin led to notable up-regulation of ZoPP2Cs (17/59/11/72/43) under chilling stress. Conclusions: Taken together, our investigation provides significant insights of the ginger PP2C gene family and establishes the groundwork for its functional validation and genetic engineering applications. [ABSTRACT FROM AUTHOR]

Long persistent luminescence (LPL) materials widely employed in the fields of emergency lighting and anti‐counterfeiting are mostly used at room temperature. As temperatures rise, the performance of LPL materials deteriorates dramatically, which hinders their application in in vivo imaging, high‐temperature display, and information storage. Herein, a multifunctional material LiGa5O8:Tb3+ (LGT) with green high‐temperature LPL (HT‐LPL) and blue cathodoluminescence (CL) is reported. Its LPL performance is anomalously enhanced with increasing temperature, and the duration time is more than 8 h at 423 K. With combined temperature‐dependent decay curves and thermoluminescence analyses, the unique quasi‐continuous defect levels are found in the band gap. The high‐concentration carriers in deep traps are frozen at room temperature and activated only at high temperatures, accompanied by changes in energy transfer pathways. The excellent HT‐LPL makes LGT a light‐emitting component of next‐generation smart wearable devices, as well as high‐temperature warning equipment in deep well exploration at a depth of 4500 m. The intense anti‐degradation blue CL makes it suitable for field emission displays, while the manipulable emission property makes it suitable for high‐level anti‐counterfeiting. This study fills a gap in HT‐LPL materials and opens up a new gateway for the efficient design of HT‐LPL and other multifunctional materials. [ABSTRACT FROM AUTHOR]

Wheel-rail high-frequency interaction is closely related to the formation of railway short-wave defects. Finite element (FE) method has been widely used to simulate wheel-rail dynamic systems, but its validity in modelling high-frequency interaction has not been fully demonstrated in three dimensions (3D). This work aims at comprehensively validating the 3D FE modelling of wheel-rail high-frequency interaction using a downscale V-Track test rig. First, the FE model of the V-Track is developed that comprehensively includes the 3D track elasticity. The simulated track dynamic behaviours are validated against hammer tests, and the major vibration modes are analyzed employing modal analysis. Afterwards, the simulate wheel-rail dynamic responses are comprehensively compared with measurement results up to 10 kHz. Their characteristic frequencies are identified and correlated to the eigenmodes of the vehicle-track system. The results indicate that the proposed 3D FE model is capable of comprehensively and accurately simulating the 3D track dynamics and wheel-rail dynamic interaction of the V-Track up to 10 kHz. Rail vibrations dominate the wheel-rail dynamic contact within 10 kHz, while the wheel vibrations play an increasingly important role at higher frequencies and become decisive near the wheel eigenmode frequencies. The V-Track overall achieves dynamic similarity to the real vehicle-track system. [ABSTRACT FROM AUTHOR]

Dansyl chloride has been widely used in metal ion recognition as a fluorescent sensing molecule. The interaction between fluorescent probes and metal ions is summarized, and the research progress in the structural design of dansyl group receptors in the field of metal ion fluorescent probes since 2010 is discussed. Its sensing mechanism involves intramolecular induced photoelectron transfer, charge transfer, dimethylamino deprotonation/protonation, formation of monomer-excitation complex, chelate-enhanced fluorescence transfer, complexation reaction, fluorescence resonance energy transfer, and other ones. The rules of the fluorescent responses of dansyl group under various mechanisms are also discussed, such as fluorescence quenching induced by intramolecular charge transfer and chelation triggered fluorescence enhancement. The future application trends of dansyl group in the field of fluorescent probe design are proposed as well. [ABSTRACT FROM AUTHOR]

Wheel-rail impact, which arises from structural discontinuities and short-wave defects, becomes more serious with higher train speeds and larger axle loads. The large impact load can accelerate the deterioration of vehicle-track components and induce a high level of impact noise. This paper aims to better understand the characteristics of wheel-rail impact and redevelop corresponding mitigation measures. First, a well-validated vehicle-track vertical interaction model with a singular rail defect is built up considering nonlinear Hertz contact. Then, the simulated wheel-rail impact force is characterized in both the time and frequency domains with different running speeds and defect geometries employing continuous wavelet transform. The identified characteristic frequencies are correlated to the track resonance modes. Afterward, a parameter sensitivity analysis of railpads, ballast, roadbed, and suspensions is performed to obtain the mitigation measures of wheel-rail impact. The results show that the wheel-rail impact force can be characterized by four stages in the time domain, the quasi-static stage before the impact, the forced vibration, the free vibration, and the quasi-static stage after the impact, respectively. Four characteristic frequencies are identified in the wheel-rail impact response: f 1 at 45 Hz, f 2 at 100 Hz, f 3 at 260 Hz, and f 4 at 810 Hz. Among them, f 4 has the dominant vibration energy and is determined together by the pinned-pinned resonance mode and the defect excitation frequency. Characteristic frequencies f 1, f 2, and f 3 correspond to the ballast, sleeper, and rail resonance modes, respectively, which are independent of the defect geometry. The increase of railpad stiffness can effectively reduce the maximum wheel-rail impact force and thus the impact factor. Larger railpad stiffness and damping can significantly reduce the dominant vibration energy at about 810 Hz of f 4. This work can contribute to the optimization of vehicle-track parameters for a new design of more impact-resistant railways. [ABSTRACT FROM AUTHOR]

Memcapacitor devices based on ferroelectric material have attracted attention recently in application of neuromorphic computing due to lower static power relative to memristors. They have been used for establishing fully connected neural networks but not yet for recurrent neural networks (RNNs), which owns the advantage in temporal signal processing. As an improved network architecture for RNNs, reservoir computing (RC) is easier to train and energy efficient. In this work, an HZO-based ferroelectric memcapacitor is used as the reservoir layer to recognize handwritten digits. A recognition accuracy of 90.3% is achieved. Meanwhile, a task of predicting Mackey–Glass time series is built to demonstrate the advantage of reservoir networks in processing time-series signals. A normalized root mean square error of 0.13 was obtained, indicating that this system can predict the Mackey–Glass chaotic system well. In addition, the energy consumption in the input signal and recognition task is significantly lowered compared with a memristor-based network. Our work provides an energy efficient way to build up the RC network. [ABSTRACT FROM AUTHOR]

Hematopoietic stem cells (HSCs) with the ability to self-renew and differentiate are responsible for maintaining the supply of all types of blood cells. The complex and delicate microenvironment surrounding HSCs is called the HSC niche and can provide physical, chemical, and biological stimuli to regulate the survival, maintenance, proliferation, and differentiation of HSCs. Currently, the exploration of the biophysical regulation of HSCs remains in its infancy. There is evidence that HSCs are susceptible to biophysical stimuli, suggesting that the construction of engineered niche biophysical microenvironments is a promising way to regulate the fate of HSCs in vitro and ultimately contribute to clinical applications. In this review, we introduced the spatiotemporal heterogeneous biophysical microenvironment during HSC development, homeostasis, and malignancy. Furthermore, we illustrated how these biophysical cues contribute to HSC behaviors, as well as the possible mechanotransduction mechanisms from the extracellular microenvironment into cells. Comprehending the important functions of these biophysical regulatory factors will provide novel approaches to resolve clinical problems. [ABSTRACT FROM AUTHOR]

Pancreatic cancer (PC) carries a poor prognosis among all malignancies and poses great challenges to clinical drug accessibility due to the severely fibrotic and hypoxic tumor microenvironment (TME). Therein, cancer-associated fibroblasts (CAFs), which are extremely abundant in PC, play a key role in forming the complex PC microenvironment. Therefore, a highly efficient TME reprogramming therapeutic paradigm that can specifically inhibit CAF function is urgently needed. Herein, we successfully developed a novel CAF-tailored nanosystem (Dex-GP-DOCA, DPD) loaded with a potent anti-fibrosis flavonoid compound (Quercetin, QUE), which possesses biological responsiveness to fibroblast activation protein alpha (FAP-α), prolonged TME remodeling and enhancement of clinical chemotherapeutics. Specifically, DPD/QUE allowed for extracellular matrix (ECM) reduction, vessel normalization, hypoxia-induced drug resistance reversal, and blockade of Wnt16 paracrine in CAFs. More importantly, this chemotherapy conducive microenvironment persisted for at least 8 days following treatment with DPD/QUE. It should also be noted that the effective and prolonged microenvironment modulation induced by DPD/QUE significantly improved the chemotherapy sensitivity of Abraxane and gemcitabine, the first-line chemotherapeutic drugs for PC, with inhibition rates increasing from 37.5% and 40.0% to 87.5% and 85.2%, respectively. Overall, our CAFs-targeted nanosystem showed promising prospects for remodeling the TME and facilitating chemotherapy for refractory pancreatic cancer. [Display omitted] [ABSTRACT FROM AUTHOR]

Key message: The 14–3–3 family is more highly conserved among monocotyledons, and overexpression of MdGRF13 improved drought and salt tolerance in transgenic Arabidopsis thaliana. The 14–3–3 are highly conserved regulatory proteins found in eukaryotes and play an essential role in plant growth, development and stress response. However, the 14–3–3 gene family evolution in monocotyledons and dicotyledons and the biological functions of the MdGRF13 under abiotic stress remain unknown. In our study, 195 members of the 14–3–3 family were identified from 12 species and divided into ε group and the Non-ε group. Synteny analysis within the 14–3–3 family indicated that segmental duplication events contributed to the expansion of the family. Selective pressure analysis indicated that purifying selection was a vital force in the 14–3–3 genes evolution, and monocotyledons had a lower million years ago (Mya) mean values than dicotyledons. Meanwhile, the codon adaptation index (CAI) and frequency of optical codons (FOP) are higher and the effective number of codons (Nc) is lower in monocotyledons 14–3–3 genes compared to dicotyledons. Moreover, the yeast two-hybrid (Y2H) demonstrated that MdGRF13 interacts with MdRD22, MdLHP1a and MdMORF1. Significantly, the malondialdehyde (MDA) content and relative conductivity were decreased, while the superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities were increased in transgenic Arabidopsis compared to the wild type (WT) under drought and salt stress. These results suggest that overexpression of MdGRF13 significantly improved the tolerance to drought and salt stress in transgenic Arabidopsis. Thus, our results provide a theoretical basis for exploring the evolution and function of the 14–3–3 gene family in monocotyledons and dicotyledons. [ABSTRACT FROM AUTHOR]

In this manuscript, we study the non-Hermitian spin-1/2 XY model in the presence of the alternating, imaginary and transverse magnetic fields. For the two-site spin system, we solve exactly the energy spectrum and phase diagram and also calculate the ground-state and thermal entanglements by using the concept of the concurrence. It is found that the two-site concurrence in the eigenstate which only depends on the imaginary magnetic field η is always equal to one in the region of P T symmetry, while it decreases with η in the P T -symmetric broken region; especially, the first derivative of concurrence shows the non-analytic behavior at the exceptional point, and the same is true in the case of the biorthogonal basis, which indicates that the concurrence can characterize the phase transition in this non-Hermitian system. The interesting thing is that η weakens the thermal entanglement when the system is isotropic and enhances the entanglement when the system belongs to the Ising universality class. For the one-dimensional spin chain, the magnetization and entanglement are further studied by using the two-spin cluster mean-field approximation. The results show that their variations have opposite trends with the magnetic fields. Moreover, the system exists the first-order quantum phase transitions for some anisotropic parameters in the P T -symmetry region, and the entanglement changes suddenly at the quantum phase transition point. [ABSTRACT FROM AUTHOR]

Cyclophilin D (CypD) is regulated during the innate immune response of insects. However, the mechanism by which CypD is activated under innate immunosuppression is not understood. Microplitis bicoloratus bracovirus (MbBV), a symbiotic virus in the parasitoid wasp, Microplitis bicoloratus, suppresses innate immunity in parasitized Spodoptera litura. Here, we demonstrate that MbBV promotes the CypD acetylation of S. litura, resulting in an immunosuppressive phenotype characterized by increased apoptosis of hemocytes and MbBV-infected cells. Under MbBV infection, the inhibition of CypD acetylation significantly rescued the apoptotic cells induced by MbBV, and the point-mutant fusion proteins of CypDK125R-V5 were deacetylated. The CypD-V5 fusion proteins were acetylated in MbBV-infected cells. Deacetylation of CypDK125R-V5 can also suppress the MbBV-induced increase in apoptosis. These results indicate that CypD is involved in the MbBV-suppressed innate immune response via the CypD-acetylation pathway and S. litura CypD is acetylated on K125. [ABSTRACT FROM AUTHOR]

Background: Circular RNAs (circRNAs) have been reported to exert critical functions in tumorigenesis and development. However, the underlying mechanism by which circRNAs regulate melanoma progression remain to be elucidated. Methods: The differentially expressed circRNAs were first identified by circRNA-seq, and circRNAs were validated via qRT-PCR and Sanger sequencing. Then, the impact of circRPS5, miR-151a and NPTX1 expression on the progression of melanoma cell were determined by gain- and loss-of-function assays. The relationship between circRPS5, miR-151a, and NPTX1 was predicted by StarBase website and authenticated by luciferase reporter assay. The melanoma cells-derived exosomes were characterized using nanoparticle tracking analysis (NTA) and western blot. Results: CircRPS5 was significantly downregulated in melanoma tissues and cell lines. Functionally, circRPS5 suppressed the proliferation, migration, and invasion of melanoma cells, and induced cell cycle arrest and apoptosis in vitro. Mechanistically, circRPS5 harbor miR-151a, acting as miRNA sponge, and then miR-151a targeted the 3'-UTR of NPTX1. Finally, circRPS5 was mainly incorporated into exosomes to inhibit the progression of melanoma cells. Conclusions: This finding reveal circRPS5 suppressed the progression of melanoma through miR-151a/NPTX1 pathway, and may provide a promising therapeutic strategies for melanoma. [ABSTRACT FROM AUTHOR]

It has been demonstrated that contrast sensitivity is sensitive to stimulus exposure duration. Here, we investigated how the duration effect on contrast sensitivity was modulated by the spatial frequency and intensity of external noise. Through a contrast detection task, the contrast sensitivity function under 10 spatial frequencies, three external noise, and two exposure duration conditions was measured. The temporal integration effect was defined by the difference in contrast sensitivity or the area under the log contrast sensitivity function between short and long exposure durations. We found that (1) the temporal integration effect was less pronounced in the zero‐noise condition than in the low‐ or high‐noise condition; (2) in the zero‐noise condition, a stronger temporal integration effect was observed at high spatial frequencies; (3) in the high‐noise condition, a stronger temporal integration effect was observed at low spatial frequencies; (4) the spatial‐frequency‐dependent transient or sustained mechanism is also sensitive to external noise level; and (5) perceptual template model analysis revealed that both decreased additive internal noise and an improved perceptual template accounted for the temporal integration effect, and these two factors were tuned to spatial frequency. [ABSTRACT FROM AUTHOR]

Motivation The coronavirus disease 2019 (COVID-19) remains a global public health emergency. Although people, especially those with underlying health conditions, could benefit from several approved COVID-19 therapeutics, the development of effective antiviral COVID-19 drugs is still a very urgent problem. Accurate and robust drug response prediction to a new chemical compound is critical for discovering safe and effective COVID-19 therapeutics. Results In this study, we propose DeepCoVDR, a novel COVID-19 drug response prediction method based on deep transfer learning with graph transformer and cross-attention. First, we adopt a graph transformer and feed-forward neural network to mine the drug and cell line information. Then, we use a cross-attention module that calculates the interaction between the drug and cell line. After that, DeepCoVDR combines drug and cell line representation and their interaction features to predict drug response. To solve the problem of SARS-CoV-2 data scarcity, we apply transfer learning and use the SARS-CoV-2 dataset to fine-tune the model pretrained on the cancer dataset. The experiments of regression and classification show that DeepCoVDR outperforms baseline methods. We also evaluate DeepCoVDR on the cancer dataset, and the results indicate that our approach has high performance compared with other state-of-the-art methods. Moreover, we use DeepCoVDR to predict COVID-19 drugs from FDA-approved drugs and demonstrate the effectiveness of DeepCoVDR in identifying novel COVID-19 drugs. Availability and implementation https://github.com/Hhhzj-7/DeepCoVDR. [ABSTRACT FROM AUTHOR]

Both direct and indirect heating compression methods were proposed to satisfy the requirement of industrial steam compression and supply. The compression process in a single-screw compressor was analyzed with the determination of different inlet and outlet boundary conditions. Considering the misalignment of meshing pairs caused by the offset of the star wheel axis and screw origin, the differential expansion of the vertical meshing pair was further analyzed. The inner ring of the sealing end face, the wall of the inner ring of the bearing at the inlet and outlet ends, and the bottom surface of the bracket were analyzed by different coordinate systems and different constraints, thus facilitating the design and selection of the single screw. The critical point for the design of a steam-type single-screw compressor is an outlet temperature of 350 °C and an outlet volume flow rate of 130 m3/min. At a flow rate of 130 m3/min, when the temperature exceeds 350 °C, the reliability of the compressor is still limited, and the differential expansion of the meshing pair exceeds 0.3 mm. In addition, superheating of steam can be improved by applying a centrifugal compressor with cascade compression and centrifugal compression in conjunction with reflux adjustment at the compression outlet. [ABSTRACT FROM AUTHOR]

Since magnetic field is penetrating and harmless to human body, magnetic soft robots driven by magnetic field have great potential in medical fields. Thus, magnetic soft robots have attracted wide attention. However, the current researches mainly focus on the design of a single magnetic soft robot. Multiple magnetic soft robots also deserve to be studied due to their applications in collaborative operation. This paper presents a new design and fabrication method of multiple magnetic small-scale soft robots with different magnetic strength, size, and length-width ratio. The robots can be controlled to move in different motion modes and motion states under identical magnetic field. By analyzing their magnetic response property, which is the switching conditions between the two motion modes, and analyzing their states of the walking motion, two robots are selected from a batch of fabricated robots to carry out experiment. The results show that the two robots can move in different motion modes in the identical magnetic field. [ABSTRACT FROM AUTHOR]

A low‐profile circularly polarized folded reflectarray antenna (CPFRA) with linearly polarized (LP) feed antenna is presented in this article. Polarizing grid usually used as the subreflector of traditional FRA is replaced by a polarization‐sensitive frequency selective surface (FSS) in the CPFRA design. The polarization‐sensitive FSS is designed to convert the LP incidence into the CP wave within its passband while reflecting the orthogonal LP incident wave over its operating frequency band. A CPFRA prototype has been proposed and validated for Ka band satellite communications uplinks in this article. The maximum measured antenna gain of 26.0 dBic is achieved at 29.75 GHz with the corresponding antenna aperture efficiency of 40%. Beam scanning property has been achieved by the CPFRA with the mechanical movement of feed horn antenna. All the measured axial ratios (ARs) of the CPFRA are lower than 3 dB in the frequency range from 29 to 30.25 GHz. Meanwhile, the measured antenna gain variation with different beam scanning angles is less than 1 dB from 29.25 to 31 GHz. [ABSTRACT FROM AUTHOR]

Multiparameter sensors that can individually monitor mechanical and thermal signals from multiple stimuli have attracted immense attention. Due to interferences caused by signal crosstalk, it is a challenge for multiparameter sensors to simultaneously differentiate mechanic and thermal stimuli within a broad working range. Herein, a liquid‐metal‐based stretchable dual‐parameter sensor that can simultaneously detect deformation (0–4.5 mm) and temperature (0–60 °C) is fabricated. The sensor adopts a multilayer structure in which a capacitive deformation‐sensing unit is stacked on top of a resistive temperature‐sensing unit. The deformation unit possesses excellent linear responses (R2 = 0.999) and ultralow detection limit (0.04 mm, ≈0.02%). Attributed to these merits, the deformation unit can be used to monitor physiological actions (e.g., finger bending, swallowing, and speaking). The temperature unit exhibits strong stability under multiple stimuli. With the cooperation of the two units, the dual‐parameter sensor can accurately differentiate deformation and temperature stimuli with an average error of 0.04 mm and 0.82 °C. Because of these remarkable performances, the sensor can achieve real‐time acquisition of the deformation and temperature change during finger movements. The dual‐parameter sensing abilities of the sensor indicate its promising potential in human motion monitoring and wearable devices. [ABSTRACT FROM AUTHOR]

Strong-scattering medium can usually form a good sealing medium for oil and gas resources. However, conventional elastic full-waveform inversion (EFWI) methods are difficult to build reliable velocity models under the condition of lacking low-frequency information. The elastic direct envelope inversion (EDEI) method has been proven to be able to model large-scale Vp and Vs structures of strong-scattering media. The successive use of EDEI and EFWI can obtain fine structures of the strong scatterers and their shielding areas. However, the inversion effects of inner velocity and bottom boundaries of strong scatterers by the existing methods need to be improved. In this paper, we propose the elastic direct envelope inversion with anisotropic total variation constraint (EDEI-ATV). The anisotropic total variation (ATV) constraint has the advantage of making the velocity more uniform inside the layer and sharper on boundaries, which can be used to improve the inversion results of EDEI. During the iterations, the ATV constraint is directly applied to the update of Vp and Vs, and the alternately iterative algorithm can achieve good results. After obtaining reliable large-scale Vp and Vs structures, the EFWI with anisotropic total variation constraint (EFWI-ATV) is performed to obtain high-precision Vp and Vs structures. Numerical examples verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Visual perceptual learning (VPL) has great potential implications for clinical populations, but adequate improvement often takes weeks to months to obtain; therefore, practical applications of VPL are limited. Strategies that enhance visual performance acquisition make great practical sense. Transcranial direct current stimulation (tDCS) could be beneficial to VPL, but thus far, the results are inconsistent. The current study had two objectives: (1) to investigate the effect of anodal tDCS on VPL and (2) to determine whether the timing sequence of anodal tDCS and training influences VPL. Anodal tDCS was applied on the left human middle temporal (hMT+) during training on a coherent motion discrimination task (online), anodal tDCS was also applied before training (offline) and sham tDCS was applied during training (sham). The coherent thresholds were measured without stimulation before, 2 days after and 1 month after training. All participants trained for five consecutive days. Anodal tDCS resulted in more performance improvement when applied during daily training but not when applied before training. Additionally, neither within‐session improvement nor between‐session improvement differed among the online, offline and sham tDCS conditions. These findings contribute to the development of efficient stimulation protocols and a deep understanding of the mechanisms underlying the effect of tDCS on VPL. [ABSTRACT FROM AUTHOR]

To evaluate the short‐term and long‐term survival efficacy of an artificial liver support system (ALSS) in patients with acute‐on‐chronic liver failure (ACLF). A systematic search was performed for relevant published data in PubMed, Web of Science and Cochrane Library databases. Studies that evaluated the efficacy of ALSS in patients with ACLF and provided the short‐term or long‐term survival rate were included. A total of 10 studies involving 3685 patients were included in this analysis. The pooled 28‐day survival rate and 90‐day survival rate were 68.7% (95% CI: 64.5%–72.9%) and 53.4% (95% CI: 45.5%–61.4%), respectively. The pooled estimates of the OR for the 28‐day and 90‐day survival rates between the ALSS group and the control group were 1.91 (95% CI: 1.21–3.04) and 1.41 (95% CI: 1.17–1.70), respectively. Subgroup analysis showed that patients treated with lower levels of TBIL and MELD scores had a higher 28‐day survival rate (χ2 = 15.75, p < 0.01; χ2 = 13.80, p < 0.01). The present meta‐analysis suggests that ALSS treatment could remarkably improve short‐term survival rates in HBV‐ACLF patients, which implies that treatment with ALSS may help to reduce high mortality. Further prospective randomized trials are needed to validate these findings. [ABSTRACT FROM AUTHOR]

The gearbox of the small joint steering gear of a service robot is characterized by a compact structure, a large reduction ratio, and a special manufacturing and assembling technology. However, when a tooth in the gear is broken, the gear transmission can be still maintained, so it is difficult to identify the broken tooth accurately. In order to provide a theoretical basis for the identification of a broken tooth in the study, the influence of gear tooth fracture on the time-varying meshing stiffness in the transmission process was firstly analyzed theoretically and its influencing mechanisms on the time domain and frequency domain characteristics of transmission error (TE) were further analyzed. Then, the TE measurement test bench of the joint steering gear was designed. The signal-to-noise ratios and root-mean-square errors of the TE data processed by wavelet noise reduction, Kalman filtering and combined wavelet-Kalman filtering algorithms were compared and analyzed. The analysis results showed that the joint algorithm had the best performance. Next, the TE data measured under multiple working conditions were processed with the joint filtering algorithm to obtain the time domain results and then the frequency domain results were obtained by Fourier transform. Whether there was a broken tooth in the joint steering gear could be judged based on the difference between the maximum and minimum values of the TE in the time domain. The broken-tooth gear shaft could be positioned based on the frequency of TE mutation waveform. Furthermore, combined with the frequency domain, the accurate identification of the position of the broken gear can be realized. Finally, the accurate positioning method of broken teeth was applied in the product inspection process. Broken teeth were successfully identified and located, thus proving the effectiveness of the identification method. [ABSTRACT FROM AUTHOR]

To investigate the key genes affecting ovarian development in the ridgetail white prawn, Exopalaemon carinicauda, we cloned the full‐length cDNA of the CDK9 gene and discussed its role in ovarian development. Our results show that the gene has an open reading frame of 1155 bp, encoded 383 amino acids, and it has a conserved cyclin binding motif S_TKc. The open reading frame of CDK9 was expressed as a 43.96 Kda molecular weight protein. The phylogenetic tree analysis showed that the CDK9 gene has the highest homology with the CDK9 genes of Penaeus vannamei and Penaeus japonicus. The results of qRT‐PCR show that the CDK9 gene was also expressed in the eye stalk, stomach, heart, gill, intestine, muscle, ovary, hepatopancreas and ventral cord. The expression level was highest in the ovary, which was significantly different from the other tissues (p < 0.05). In the five stages of ovarian development, the expression level of the CDK9 gene was highest in stage I, which was significantly different from the other stages (p < 0.05). In situ hybridization tests showed strong expression signals in the membrane, cytoplasm and nucleus of oocytes and previtellogenic oocytes. Nevertheless, following the proliferation of oocytes, the expression signals became much stronger in the oocyte membrane and in the whole follicular cells located in the interstitial space. The RNA interference results show that the expression of the CDK9 gene significantly affects the expression of the Vg and VgR genes. Our findings suggest that CDK9 plays an important role in the synthesis and transportation of vitellin. [ABSTRACT FROM AUTHOR]

(1) Background: Alfalfa is an important legume forage throughout the world. Although alfalfa is considered moderately tolerant to salinity, its production and nitrogen-fixing activity are greatly limited by salt stress. (2) Methods: We examined the physiological changes and proteomic profiles of alfalfa with active nodules (NA) and without nodules (NN) under NaCl treatment. (3) Results: Our data suggested that NA roots showed upregulation of the pathways of abiotic and biotic stress responses (e.g., heat shock proteins and pathogenesis-related proteins), antioxidant enzyme synthesis, protein synthesis and degradation, cell wall degradation and modification, acid phosphatases, and porin transport when compared with NN plants under salt stress conditions. NA roots also upregulated the processes or proteins of lipid metabolism, heat shock proteins, protein degradation and folding, and cell cytoskeleton, downregulated the DNA and protein synthesis process, and vacuolar H+-ATPase proteins under salt stress. Besides, NA roots displayed a net H+ influx and low level of K+ efflux under salt stress, which may enhance the salt tolerance of NA plants. (4) Conclusions: The rhizobium symbiosis conferred the host plant salt tolerance by regulating a series of physiological processes to enhance stress response, improve antioxidant ability and energy use efficiency, and maintain ion homeostasis. [ABSTRACT FROM AUTHOR]

The RING (Really Interesting New Gene) finger proteins are a large diverse group of Zinc finger proteins. Many determined RING finger proteins are ubiquitin-protein E3 ligases and RING E3s are the most abundant type of ubiquitin ligase. RING finger and RING finger E3s have been discovered in many organisms where they play various functions, including DNA repair, ubiquitination and mitochondrial protein quality control. In this study, we identified a novel mitochondrial protein (SPBC16G5.03) with predicted RING finger domain within an N-terminal 21–60 amino acids and named it Mrz1 (mitochondrial RING finger protein). Our results showed that Mrz1 is localized in the mitochondrial outer membrane. Deletion of mrz1 did not affect cell growth in an unstressed state, but increases sensitivity to selenite. We showed that Mrz1 was degraded during the stationary phase and blocked by addition proteasome inhibitor MG132. We further showed that the E2 enzyme Ubc13 was identified among 8 candidate proteins as the ubiquitin-conjugating enzyme in this system. These data suggested that the Mrz1 was degraded likely through the ubiquitin–proteasome system. [ABSTRACT FROM AUTHOR]

The Darbut ophiolitic mélange is located in the central West Junggar area, southwestern Central Asian Orogenic Belt (CAOB), and rodingites are widespread within serpentinized peridotites in the mélange. Here, we conducted field, structural, mineralogical, and geochemical investigations of the Darbut rodingites for the first time to constrain their metasomatic processes. Rodingites usually occur as strongly sheared blocks surrounded by chloritic blackwall, and their preferred axial surface orientations are subparallel to the serpentinite foliations. Based on the petrology and geochemistry of these metasomatic rocks, two stages of metasomatic processes, namely rodingitization and derodingitization, were recognized: (1) rodingitization of gabbroic protolith was characterized by the input of Ca and the release of Si, K, Na, and LILE; this stage was related to the diapiric emplacement of the Darbut ophiolitic mélange in the Late Carboniferous; and (2) derodingitization of rodingites led to the replacement of Ca-rich minerals by chlorite, accompanied by Mg increase, and depletions of Ca and REE; the derodingitization stage occurred under enhanced CO2/H2O ratio conditions and was likely associated with regional postcollision volcanism in the Early Permian. Hence, the rodingite in the Darbut ophiolitic mélange provides important fingerprints recording the tectonic evolution. [ABSTRACT FROM AUTHOR]

In this paper, we define a family of functionals generalizing the Yang–Mills–Higgs functionals on a closed Riemannian manifold. Then we prove the short-time existence of the corresponding gradient flow by a gauge-fixing technique. The lack of a maximum principle for the higher order operator brings us a lot of inconvenience during the estimates for the Higgs field. We observe that the $L^2$ -bound of the Higgs field is enough for energy estimates in four dimensions and we show that, provided the order of derivatives appearing in the higher order Yang–Mills–Higgs functionals is strictly greater than one, solutions to the gradient flow do not hit any finite-time singularities. As for the Yang–Mills–Higgs k-functional with Higgs self-interaction, we show that, provided $\dim (M) , for every smooth initial data the associated gradient flow admits long-time existence. The proof depends on local $L^2$ -derivative estimates, energy estimates and blow-up analysis. [ABSTRACT FROM AUTHOR]

The construction industry is becoming increasingly interested in blockchains, and relevant publications have blossomed in recent years. This study provided a state-of-the-art review of blockchain research in the industry in order to better comprehend the fast-evolving technology. A systematic method integrating quantitative and qualitative analyses was used to capture the research status, challenges, and future directions based on 141 publications published between 2017 and 2021. The distributions of 141 papers were quantitatively analyzed in terms of chronology, geography, journal, and research type. The majority of blockchain applications focused on the construction stage, while progress payment management and supply chain management were the top two topics. Different blockchain applications throughout the entire lifecycle of building projects were also introduced through qualitative analyses. Finally, this research indicated the challenges and future directions of blockchain research in the construction industry. This review provides valuable information to help construction researchers and practitioners understand blockchain research advances and better determine research opportunities. [ABSTRACT FROM AUTHOR]

Happiness studies generally investigate average levels of happiness rather than happiness inequality between regions, and studies of social inequality usually measure it based on the distribution of life opportunities (e.g., income) rather than life results (e.g., happiness). Inspired by the Kuznets curve, which illustrates the inverted U-shaped correlation between income inequality and economic growth, this study investigates whether there is a subjective wellbeing Kuznets curve. It uses data from ten waves of the Chinese General Social Survey to construct a panel data set and runs panel data models to investigate the hypothesized curvilinear relationship between happiness inequality and economic growth. The results show that happiness inequality, measured as the standard deviations of respondents' self-reported happiness, first increases and then decreases as per-capita GDP increases in Chinese provinces. These findings strongly support the subjective wellbeing Kuznets curve hypothesis and suggest that strategies for reducing happiness inequality must consider stages of economic development. [ABSTRACT FROM AUTHOR]

The traveling salesman problem (TSP) widely exists in real-life practical applications; it is a topic that is under investigation and presents unsolved challenges. The existing solutions still have some challenges in convergence speed, iteration time, and avoiding local optimization. In this work, a new method is introduced, called the discrete carnivorous plant algorithm (DCPA) with similarity elimination to tackle the TSP. In this approach, we use a combination of six steps: first, the algorithm redefines subtraction, multiplication, and addition operations, which aims to ensure that it can switch from continuous space to discrete space without losing information; second, a simple sorting grouping method is proposed to reduce the chance of being trapped in a local optimum; third, the similarity-eliminating operation is added, which helps to maintain population diversity; fourth, an adaptive attraction probability is proposed to balance exploration and the exploitation ability; fifth, an iterative local search (ILS) strategy is employed, which is beneficial to increase the searching precision; finally, to evaluate its performance, DCPA is compared with nine algorithms. The results demonstrate that DCPA is significantly better in terms of accuracy, average optimal solution error, and iteration time. [ABSTRACT FROM AUTHOR]

The roots of Sophora tonkinensis Gagnep., a traditional Chinese medicine, is known as Shan Dou Gen in the Miao ethnopharmacy. A large number of previous studies have suggested the usage of S. tonkinensis in the folk treatment of lung, stomach, and throat diseases, and the roots of S. tonkinensis have been produced as Chinese patent medicines to treat related diseases. Existing phytochemical works reported more than 300 compounds from different parts and the endophytic fungi of S. tonkinensis. Some of the isolated extracts and monomer compounds from S. tonkinensis have been proved to exhibit diverse biological activities, including anti-tumor, anti-inflammatory, antibacterial, antiviral, and so on. The research progress on the phytochemistry and pharmacological activities of S. tonkinensis have been systematically summarized, which may be useful for its further research. [ABSTRACT FROM AUTHOR]

Studies related to oil and gas wells have attracted worldwide interest due to the increasing energy shortfall and the requirement of sustainable development and environmental protection. However, the state of oil and gas wells in terms of research characteristics, technological megatrends, article-produced patterns, leading study items, hot topics, and frontiers is unclear. This work is aimed at filling the research gaps by performing a comprehensive bibliometric analysis of 6197 articles related to oil and gas wells published between 1900 and 2021. VOSviewer and CiteSpace software were used as the main data analysis and visualization tools. The analysis shows that the annual variation of article numbers, interdisciplinary numbers, and cumulative citations followed exponential growth. Oil and gas well research has promoted the expansion of research fields such as engineering, energy and fuels, geology, environmental sciences and ecology, materials science, and chemistry. The top 10 influential studies mainly focused on shale gas extraction and its impact on the environment. More studies were produced by larger author teams and inter-institution collaborations. Elkatatny and Guo have greatly contributed to the application of artificial intelligence in oil and gas wells. The two most contributing institutions were the Southwest Petr Univ and China Univ Petr from China. The People's Republic of China, the US, and Canada were the countries with the most contributions to the development of oil and gas wells. The authoritative journal in engineering technology was J Petrol Sci Eng, in environment technology was Environ Sci Technol, in geology was Aapg Bull, and in materials was Cement Concrete Res. The keyword co-occurrence network cluster analysis indicated that oil well cement, new energy development, machine learning, hydraulic fracturing, and natural gas and oil wells are the predominant research topics. The research frontiers were oil extraction and its harmful components (1992–2016), oil and gas wells (1997–2016), porous media (2007–2016), and hydrogen and shale gas (2012–2021). This paper comprehensively and quantitatively analyzes all aspects of oil and gas well research for the first time and presents valuable information about active and authoritative research entities, cooperation patterns, technology trends, hotspots, and frontiers. Therefore, it can help governments, policymakers, related companies, and the scientific community understand the global progress in oil and gas well research and provide a reference for technology development and application. [ABSTRACT FROM AUTHOR]

Background: The COVID-19 pandemic worsens populations' mental health. However, little is known about the COVID-19-related mental health among remote workers.Methods: We retrieved data from survey of Health, Ageing and Retirement in Europe, covering 27 countries. Eligible people were those employed. The main outcome is the mental disorder, covering four aspects: depression, anxiety, sleep disorder, and loneliness. Country-specific weighted mixed models were fitted to estimate the association of workplaces with mental health, controlled for age, gender, education level, living alone, making ends meets, working hours, closing to suspected or confirmed COVID-19 cases, received anti-virus protection, social contact, disability, and chronic disease. Moderate analyses were conducted to explore possible mechanisms.Results: 11,197 participants were included, among them 29.3% suffered at least one worse mental disorder. After controlling for covariates, compared with those who worked at the usual workplace, those who worked at home only or part of the time did not associate with worse mental disorders (p-value ≥0.1395), and those who worked at neither the usual workplace nor home had a 55% higher likelihood of suffering from worse mental disorders (OR = 1.55, 95%CI 1.03-2.36). The mediation analyses identified three indirect pathways by which workplaces influence mental health, including making ends meets, social contact, and receiving anti-virus protection. Detailed results on subtypes of mental disorders were also provided.Limitations: All assessments were self-reported, resulting in a risk of method bias.Conclusions: During the COVID-19 pandemic, working at other places, neither at the usual workplace nor home, worsened mental health. Evidence provided in this study will contribute to more nuanced and practical public health policy strategy making. [ABSTRACT FROM AUTHOR]

Control of planar underactuated manipulators (PUM) with unknown parameter perturbations and external disturbances is still a challenging task due to their complex and peculiar characteristics. The research on it is significant in the view of wide applications in practice. In this paper, taking an uncertain 3-degree of freedom PUM with a free first joint as a benchmark example, we discuss its position control issue. Specifically, an integrated control method is developed, including the nonlinear model prediction control (NMPC) based on an improved particle swarm optimisation (PSO) algorithm and the discrete-time fast terminal sliding mode (FTSM) control. The PSO-based NMPC is proposed for planning discrete trajectories of the active joint angles in real time, along which the manipulator end-point can reach the desired position. Then the discrete-time FTSM controllers are designed to keep the active joints tracking the discrete trajectories, where the uncertainties related to the active links/joints are estimated by time delay estimation method. Besides, the influence of the uncertainties related to the free link/joint on the system can be made up by the NMPC in real time. It is confirmed via simulations that the above method can achieve the accurate positioning of such an uncertain manipulator. [ABSTRACT FROM AUTHOR]

Background: As a DNA surveillance mechanism, cell cycle checkpoint has recently been discovered to be closely associated with lung adenocarcinoma (LUAD) prognosis. It is also an essential link in the process of DNA damage repair (DDR) that confers resistance to radiotherapy. Whether genes that have both functions play a more crucial role in LUAD prognosis remains unclear.Methods: In this study, DDR-related genes with cell cycle checkpoint function (DCGs) were selected to investigate their effects on the prognosis of LUAD. The TCGA-LUAD cohort and two GEO external validation cohorts (GSE31210 and GSE42171) were performed to construct a prognosis model based on the least absolute shrinkage and selection operator (LASSO) regression. Patients were divided into high-risk and low-risk groups based on the model. Subsequently, the multivariate COX regression was used to construct a prognostic nomogram. The ssGSEA, CIBERSORT algorithm, TIMER tool, CMap database, and IC50 of chemotherapeutic agents were used to analyze immune activity and responsiveness to chemoradiotherapy.Results: 4 DCGs were selected as prognostic signatures, and patients in the high-risk group had a lower overall survival (OS). The lower infiltration levels of immune cells and the higher expression levels of immune checkpoints appeared in the high-risk group. The damage repair pathways were upregulated, and chemotherapeutic agent sensitivity was poor in the high-risk group.Conclusions: The 4-DCGs signature prognosis model we constructed could predict the survival rate, immune activity, and chemoradiotherapy responsiveness of LUAD patients. [ABSTRACT FROM AUTHOR]

• The first-ever systematic experimental program on the transverse tension tests of PGFRP profiles using non-standard short coupons was presented. • Size effects on transverse tensile properties in terms of coupon width and gauge length were examined. • Finite element models were developed to provide a better understanding of the failure mechanisms of the transverse short coupons under tension. • Recommended short coupon configuration for transverse tension tests of PGFRP profiles was eventually proposed. Pultruded glass fiber-reinforced polymer (PGFRP) profiles, manufactured via a pultrusion process, are increasingly used in civil engineering. However, due to the anisotropic nature, their transverse material properties are weaker than the longitudinal ones, necessitating robust material characterization methods for transverse properties. Commercially available PGFRP profiles often have insufficiently large cross-sections for standard-sized transverse tensile tests, prompting the need to investigate the effect of coupon size on transverse tensile properties and propose a feasible shorter coupon size. This paper therefore aims to examine the coupon-size effects and propose suitable short coupon geometries for transverse tensile tests. Standard material characterization tests were conducted on channel-section PGFRP profiles, followed by transverse tensile tests on six types of non-standard short coupons. The effects of coupon width and gauge length on transverse tensile properties were evaluated and compared across six aspects, with potential failure mechanisms further explored using finite element analysis (FEA). The paper concludes by proposing a feasible short coupon configuration for transverse tensile tests. [ABSTRACT FROM AUTHOR]

• Sandwich panels with armored hybrid core were designed against combined blast loading. • Synergetic damage behaviors of sandwich panels were investigated experimentally. • Effects of the face-sheet and core configurations on the panel performance were unveiled. Synergetic damage under combined blast and fragment loading drives innovational design of protective structures. In present study, sandwich panel with armored hybrid core was designed, fabricated and finally tested under combined blast and fragment loading. The failure behaviors and the underlying mechanisms were analyzed for the components of sandwich panel. The sandwich panel displayed superior performance over equivalent solid plate. The designability of special interest was exploited by elaborating the effects of face sheet configuration, core material and core sequence on the failure behaviors. Experimental results demonstrate that the same thickness of the front and back faces is beneficial for the constraint of back face deflection. The aluminum foam and ultra-high molecular weight polyethylene (UHMWPE) laminate, adopted as the components of armored hybrid core, cooperated well against combined blast and fragment loading by suffering crushing erosion failure and global bulge deformation, respectively. The potential of armored hybrid core is strongly associated with the core sequence. The ceramic layer supported by the material with high stiffness and the protection of upper bulletproof material for UHMWPE laminate layer would benefit the performance of whole panel. The optimal design of core sequence could markedly reduce back face deflection and even avoid the petalling failure of back face. [ABSTRACT FROM AUTHOR]

Fluorescence-based non-contact temperature measurement has been attested a widely-used technique for temperature aware in rotating mechanical equipment, electrical devices, and other fields. Inspired by the thermal sensitivity of perovskite nanocrystals, we prepared a CsPbBr 3 /polyhedral oligomeric silsesquioxane (POSS)-based composite film with outstanding temperature-photoluminescence (PL) dependence, high reversibility, and high hydrophobicity. Perovskites nanocrystals with controllable nanocubic and nanoplate morphologies were synthesized by adjusting the temperature. Various CsPbBr 3 /POSS-based composite films with different CsPbBr 3 morphologies and ratios were fabricated. The CsPbBr 3 nanocubic and nanoplate based films possessed high hydrophobicity, UV stability, and thermal stability. Temperature dependence experiments revealed that PL spectral parameters of CsPbBr 3 /POSS-based composite films had obvious temperature change characteristics attributable to the CsPbBr 3 morphology. The PL intensity and full width at half maximum (FWHM) of the CsPbBr 3 nanoplate based film exhibited poor regularity with temperature. In contrast, the PL intensity of the CsPbBr 3 nanocubic based film was related to temperature exponentially, and the FWHM had a strong linear relationship with temperature. Moreover, temperature dependence reversibility was realized for the CsPbBr 3 nanocubic based film. Furthermore, the applicability of a CsPbBr 3 nanocubic based temperature probe was verified by monitoring the temperature of a bearing cage on a spindle-bearing test platform. The CsPbBr 3 /POSS-based composites can be applied as temperature probes for non-contact temperature measurement of rotating components of mechanical equipment. • Facile synthesis of perovskite nanocrystal/POSS-based copolymer was realized. • Perovskite nanocubic based films exhibited better hydrophobicity and UV stability. • Perovskite nanocubic based films presented excellent PL temperature dependence. • Perovskite nanocubic based films possessed durability and reversibility. • The composite films demonstrated potential for non-contact temperature probes. [ABSTRACT FROM AUTHOR]

Postprandial distress syndrome (PDS) is the most common functional dyspepsia (FD) subtype. Early satiety is one of the cardinal symptoms of the PDS subtype in FD patients. The heterogeneity of symptoms in FD patients hampered therapy for patients based on specific symptoms, necessitating a symptom-based understanding of the pathophysiology of FD. To investigate the correlation between reward circuit and symptom severity of PDS patients, seed (Nucleus accumbens, NAc, a key node in the reward circuit) based resting-state functional connectivity (FC) was applied in the neuroimaging data analysis. The results demonstrated that the patients with PDS manifested strengthened FC between NAc and the caudate, putamen, pallidum, amygdala, hippocampus, thalamus, anterior cingulate cortex (ACC), and insula. Moreover, the FC between NAc and ACC, insula, thalamus, and hippocampus exhibited significant positive associations with symptom severity. More importantly, the strengthened FC between NAc and the ACC, insula, amygdala, and hippocampus were found associated with the early satiety symptom of patients with PDS. This study indicated that the altered FC of reward circuit regions may play a role in the pathophysiology of patients with PDS, and some of the aberrant NAc-based FC within the reward circuit were more related to the early satiety of patients with PDS. These findings improve our symptom-based understanding of the central pathophysiology of FD, lay the groundwork for an objective diagnosis of FD, and shed light on the precise prescription for treating FD based on symptoms. [ABSTRACT FROM AUTHOR]