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The gaseous phytohormone ethylene participates in a lot of physiological processes in plants. 1-aminocyclopropane-1-carboxylic acid (ACC) synthase (ACS, EC 4.4.1.14) and the ACC oxidase (ACO, EC 1.14.17.4) are key enzymes in ethylene biosynthesis. However, how ACSs and ACOs are regulated at the transcriptional level is largely unknown. In the present study, we showed that an Arabidopsis (Arabidopsis thaliana) WRKY-type transcription factor (TF), WRKY29 positively regulated the expression of ACS5, ACS6, ACS8, ACS11 and ACO5 genes and thus promoted basal ethylene production. WRKY29 protein was localized in nuclei and was a transcriptional activator. Overexpression of WRKY29 caused pleiotropic effect on plant growth, development and showed obvious response even without ACC treatment. Inducible overexpression of WRKY29 also reduced primary root elongation and lateral root growth. A triple response assay of overexpression and mutant seedlings of WRKY29 showed that overexpression seedlings had shorter hypocotyls than the transgenic GFP (Green Fluorescence Protein) control, while mutants had no difference from wild-type. A qRT-PCR assay demonstrated that expression of multiple ACSs and ACO5 was up-regulated in WRKY29 overexpression plants. A transactivation assay through dual luciferase reporter system confirmed the regulation of promoters of ACS5, ACS6, ACS8, ACS11 and ACO5 by WRKY29. Both in vivo chromatin immunoprecipitation (ChIP)- quantitative PCR and in vitro electrophoretic mobility shift assay (EMSA) revealed that WRKY29 directly bound to the promoter regions of its target genes. Taken together, these results suggest that WRKY29 is a novel TF positively regulating ethylene production by modulating the expression of ACS and ACO genes.

Wall shear stress (WSS) contributes to the mechanotransduction underlying microvascular development and regeneration. Using computational fluid dynamics, we elucidated the interplay between WSS and vascular remodelling in a zebrafish model of tail amputation and regeneration. The transgenic Tg ( fli1:eGFP ; Gata1:ds-red ) zebrafish line was used to track the three-dimensional fluorescently labelled vascular endothelium for post-image segmentation and reconstruction of the fluid domain. Particle image velocimetry was used to validate the blood flow. Following amputation to the dorsal aorta and posterior cardinal vein (PCV), vasoconstriction developed in the dorsal longitudinal anastomotic vessel (DLAV) along with increased WSS in the proximal segmental vessels (SVs) from amputation. Angiogenesis ensued at the tips of the amputated DLAV and PCV where WSS was minimal. At 2 days post amputation (dpa), vasodilation occurred in a pair of SVs proximal to amputation, followed by increased blood flow and WSS; however, in the SVs distal to amputation, WSS normalized to the baseline. At 3 dpa, the blood flow increased in the arterial SV proximal to amputation and through anastomosis with DLAV formed a loop with PCV. Thus, our in silico modelling revealed the interplay between WSS and microvascular adaptation to changes in WSS and blood flow to restore microcirculation following tail amputation.

Snapshot recording of transient dynamics in three dimensions (3-D) is highly demanded in both fundamental and applied sciences. Yet it remains challenging for conventional high-speed cameras to address this need due to limited electronic bandwidth and reliance on mechanical scanning. The emergence of light field tomography (LIFT) provides a new solution to these long-standing problems and enables 3-D imaging at an unprecedented frame rate. However, based on sparse-view computed tomography, LIFT can accommodate only a limited number of projections, degrading the resolution in the reconstructed image. To alleviate this problem, we herein present a spectral encoding scheme to significantly increase the number of allowable projections in LIFT while maintaining its snapshot advantage. The resultant system can record 3-D dynamics at a kilohertz volumetric frame rate. Moreover, by using a multichannel compressed sensing algorithm, we improve the image quality with an enhanced spatial resolution and suppressed aliasing artifacts.

PurposeThe purpose of this study is to solve the problem of path planning and path tracking in the automatic parking assistant system.Design/methodology/approachThis paper first uses the method of reverse driving to confirm few control points based on the constraints of the construction of the vehicle and the environment information, then a reference path with free-collision and continuous curvature is designed based on the Bézier curve. According to the principle of the discrete linear quadratic regulator (LQR), a tracking controller that combines feedforward control and feedback control is designed.FindingsFinally, simulation analysis are carried out in Simulink and CARSIM. The results show that the proposed method can obtain a better path tracking effect when the parking space size is appropriate.Originality/valueAccording to the principle of the discrete LQR, a tracking controller that combines feedforward control and feedback control is designed.

Intervertebral disc degeneration (IVDD) is a complex age-related physiological change involving mainly cellular senescence (CS), inflammation, impaired tissue biomechanical function, and degradation of the extracellular matrix, and is a major cause of lumbar disc herniation and low back pain. Nonetheless, the specific role of CS and its associated genes in IVDD remains unclear. In this study, we first obtained 53 differentially expressed CS-related genes (CSRGs) by differential analyses of IVDD patients and non-IVDD patients from the GSE124272 and GSE150408 microarray expression datasets of the GEO database. We then performed GO and KEGG pathway enrichment analysis on these 53 CSRGs to explore their functions and pathways. To find the key genes from these 53 CSRGs, we first built a protein-protein interaction (PPI) network to recognize hub genes, and then on top of that we also applied the support vector machine recursive feature elimination (SVM-RFE) algorithm, random forest (RF) algorithm, and least absolute shrinkage and selection operator (LASSO) analysis. We finally obtained 4 hub CSRGs (DUSP3, MAPKAPK5, SP1 and VEGFA) to forecast the risk of IVDD. Based on the four hub genes we previously obtained, we built a nomogram model and performed a decision curve analysis, which ultimately suggested that the model was beneficial to patients. Based on the selected 4 hub CSRGs, we classified IVDD patients into two Hub gene patterns (hub gene clusters A and B) by the consensus clustering method, while the 297 DEGs obtained by screening based on the two hub gene clusters were classified into two gene patterns using the same method. We then applied a PCA algorithm to determine Hub gene scores for each sample to measure Hub gene patterns and found that patients in cluster A had higher Hub gene scores than those in cluster B. We also showed the correlation of two Hub gene patterns and Gene patterns with immune cell infiltration and the differential expression levels of four Hub genes by constructing heat maps and histograms. We performed GO enrichment analysis on these 297 DEGs to explore their role in IVDD. Finally, we used qPCR analysis and western blot to verify the expression levels of mRNA and protein in normal and IVDD cells of 4 hub CSRGs. In summary, CSRGs play an important role in the pathogenesis of IVDD, and our study of the hub gene cluster may guide future therapeutic strategies for IVDD.

Path tracking plays a crucial role in autonomous driving. In order to ensure the real-time performance of the controller and at the same time improve the stability and adaptability of the path tracking controller, a lateral path control strategy based on the improved LQR algorithm is proposed in this paper. To begin with, a discrete LQR controller with feedforward and feedback components is designed based on the error model of vehicle lateral dynamics constructed by the natural coordinate system. Then, a fuzzy control method is applied to adjust the weight coefficients of the LQR in real time according to the state of the vehicle. Furthermore, an update mechanism based on cosine similarity is designed to reduce the computational effort of the controller. The improved LQR controller is tested on a joint Simulink–Carsim simulation platform for a two-lane shift maneuver. The results show that the control algorithm improves tracking accuracy, steering stability and computational efficiency.

Light-field microscopy has emerged as a technique of choice for high-speed volumetric imaging of fast biological processes. However, artifacts, nonuniform resolution and a slow reconstruction speed have limited its full capabilities for in toto extraction of dynamic spatiotemporal patterns in samples. Here, we combined a view-channel-depth (VCD) neural network with light-field microscopy to mitigate these limitations, yielding artifact-free three-dimensional image sequences with uniform spatial resolution and high-video-rate reconstruction throughput. We imaged neuronal activities across moving Caenorhabditis elegans and blood flow in a beating zebrafish heart at single-cell resolution with volumetric imaging rates up to 200 Hz. Reconstruction of light-field microscopy data with a deep-learning network achieves high reconstruction speed and reduces artifacts, as illustrated for moving C. elegans and beating zebrafish hearts.

Objective: Recent advances in light-sheet fluorescence microscopy (LSFM) enable 3-dimensional (3-D) imaging of cardiac architecture and mechanics in toto . However, segmentation of the cardiac trabecular network to quantify cardiac injury remains a challenge. Methods: We hereby employed “subspace approximation with augmented kernels (Saak) transform” for accurate and efficient quantification of the light-sheet image stacks following chemotherapy-treatment. We established a machine learning framework with augmented kernels based on the Karhunen-Loeve Transform (KLT) to preserve linearity and reversibility of rectification. Results: The Saak transform-based machine learning enhances computational efficiency and obviates iterative optimization of cost function needed for neural networks, minimizing the number of training datasets for segmentation in our scenario. The integration of forward and inverse Saak transforms can also serve as a light-weight module to filter adversarial perturbations and reconstruct estimated images, salvaging robustness of existing classification methods. The accuracy and robustness of the Saak transform are evident following the tests of dice similarity coefficients and various adversary perturbation algorithms, respectively. The addition of edge detection further allows for quantifying the surface area to volume ratio (SVR) of the myocardium in response to chemotherapy-induced cardiac remodeling. Conclusion: The combination of Saak transform, random forest, and edge detection augments segmentation efficiency by 20-fold as compared to manual processing. Significance: This new methodology establishes a robust framework for post light-sheet imaging processing, and creating a data-driven machine learning for automated quantification of cardiac ultra-structure.

We present tunable image projection spectrometry (TIPS), a Fourier-domain line-scan spectral imager with a tunable compression ratio. Compared to state-of-the-art spatial-domain pushbroom hyperspectral cameras, TIPS requires much fewer measurements and provides a higher light throughput. Using a rotating Dove prism and a cylindrical field lens, TIPS scans an input scene in the Fourier domain and captures a subset of multi-angled one-dimensional (1D) en face projections of the input scene, allowing a tailored data compression ratio for a given scene. We demonstrate the spectral imaging capability of TIPS with a hematoxylin and eosin (H&E) stained pathology slide. Moreover, we showed the spectral information obtained can be further converted to depths when combining TIPS with a low-coherence full-field spectral-domain interferometer.

To improve traffic safety in undersea tunnels, the speed control effect of optical illusion deceleration markings (OIDMs) in V-shaped undersea tunnels and their applicability to drivers were explored. In this study, UC-Win/Road software was used to build a simulation scenario, and the V-shaped Jiaozhou Bay undersea tunnel in Qingdao, China, was selected as the simulated road section. Four kinds of OIDMs were selected as the research objects. According to the physiological and psychological response characteristics of drivers to the visual recognition process of OIDMs and vehicle driving parameters, three primary and six secondary evaluation indices were identified. The analytic hierarchy process-entropy weight method was applied to assign weights to each evaluation index in combination, and a comprehensive evaluation model based on the set pair analysis method and the technique for order preference by similarity to ideal solution was constructed to comprehensively evaluate the effectiveness of the OIDMs based on the ternary coefficient and the comprehensive evaluation index. To verify the accuracy of the model, the data of the three secondary evaluation indicators with larger weight coefficients were statistically analyzed, and the results showed that the results of the statistical analysis of the data were consistent with the results of the model test. In the entrance section of the tunnel, the combination of white inverted fishbone deceleration markings and red warning pavement has the highest comprehensive evaluation index of γ A1 = 0.9611. In the downhill section of the tunnel, the white variable-spacing inverted fishbone deceleration markings have the highest comprehensive evaluation index, γ B1 = 0.9644.

In general, the performance degradation data of high reliability and long life products are usually small samples due to the high price and measurement damage, while the performance degradation rule of complex products is usually nonlinear.

Degradation is a stochastic physical or chemical process in which the internal material of equipment changes asymptotically under external stress.

In the previous chapter, we discussed the performance degradation modeling and residual life prediction methods based on stochastic process, support vector machine, relevance vector machine and other data driving.

Wiener process, also known as Brownian motion, was first proposed by Robert Brown, a biologist of the UK, in 1827 based on observing the physical phenomenon that pollen particles “move irregularly” on the liquid surface. Einstein gave a mathematical description of the physical law of this phenomenon for the first time in 1905, which made a remarkable progress in this subject.

Affected by the physical or chemical property or structure of material itself, environmental stress change or other factors during various lifetime, the degeneration process of equipment will also show obvious differences in various life stages.

Particle filter (PF) is often used to estimate and predict the system state when the system model is known.

Wiener process and Gamma process are widely used in the fields of degradation modeling and residual life prediction.

Preventive maintenance is an effective means to keep the system reliability above a satisfactory level, prolong the service life of equipment and reduce the failure rate.

With the development of system science and control science, the object that under study is more and more complex.

Performance inspection is the most direct and effective method to ensure the reliability of equipment.

Generally, the core of realizing the prediction, control and decision-making of the actual system is to establish the mathematical model of the system.

Purpose The purpose of this paper is to study the effects of single parameters for temperature characteristics of oil film in port plate pair and the relationship of calculated results and experimental results under different viscosity. Design/methodology/approach The paper established the mathematical model of oil film of port plate pair, calculated the energy equation of port plate pair, simulated for the oil film and temperature distribution and selected different kinds of lubricants to analyze the calculated value and the experimental value. Findings The results show: temperature rise of port plate pair is reduced with the increase of oil viscosity; temperature rise of port plate pair is decreased with rise of initial oil film thickness; temperature rise of port plate pair is increased with the rise of cylinder body speed, inclination angle and sealing belt width; and through the comparison of calculated value and experimental value, under the same viscosity and cylinder speed, experimental results are bigger. Originality/value This paper used the methods that the temperature of port plate pair was calculated numerically, and the results were consistent with experimental results, so it can get high precision.

In this paper, we investigate an imperfect maintenance optimization problem for a multi-state, Markovian deterioration system with obvious failures under repair restriction based on those non-periodically collected sensor information. Our aim is to adaptively schedule observations and other maintenance actions with taking imperfect maintenance effect into consideration. Different from most existing works, imperfect maintenance here means that repair action can not only restore the system to a less deteriorated level instead of the good-as-new state but also accelerate the deterioration process so that the system can be repaired only a limited number of times before it must be replaced with a new one. Assuming that the system’s deterioration state evolves as a discrete-time Markov chain with a finite state space, and then choosing the information state together with the number of completed repair times as state variable, we formulate the problem as a Markov decision process over an infinite time horizon. In order to increase the computational efficiency, several key structural properties are developed by minimizing the long-run average cost per unit time. Then, special algorithms are proposed to find the optimal maintenance policies. Finally, a numerical example is given to illustrate the effectiveness of the proposed algorithms.

Leaf senescence is the last stage of leaf development and is determined by various environmental and endogenous signals. Leaf senescence can determine plant productivity and fitness. Transcription factors (TFs) with the transmembrane domain constitute a special group of regulatory proteins that can translocate from the membrane system into nuclei to exert the transcriptional function upon endogenous or exogenous stimuli. Reactive oxygen species (ROSs) play an important role in numerous processes throughout the life cycle of plants including leaf senescence. Leaf senescence is characterized by massive programmed cell death (PCD) and is a type of developmental PCD. The transcriptional regulatory relationships between membrane-bound TFs and leaf senescence remain largely uncharacterized, especially in rapeseed (Brassica napus L.), an important oil crop. Here, we show that BnaNTL1 is a membrane-bound NAC (NAM, ATAF, and CUC) TF, which is predominantly expressed in senescent leaves. Expression of BnaNTL1ΔTM, a form of BnaNTL1 devoid of the transmembrane domain, can induce serious HR-like cell death symptoms and ROS accumulation in cells. Plants overexpressing BnaNTL1ΔTM show earlier leaf senescence compared with the control, accompanied by chlorophyll degradation and electrolyte leakage. Genes involved in ROS production (RbohD), PCD (VPEs and CEP1), and leaf senescence (BFN1) are significantly induced and activated by BnaNTL1ΔTM according to the quantitative reverse transcription PCR (qRT-PCR) analysis and dual luciferase reporter (Dual-LUC) assay. Moreover, electrophoretic mobility shift assay revealed that BnaNTL1 directly bound to the NTLBS elements in promoters of RbohD, γVPE, and BFN1. In conclusion, these results demonstrate that BnaNTL1 positively modulates ROS production and HR-like cell death to induce leaf senescence.

Biomechanical forces intimately contribute to cardiac morphogenesis. However, 4-D (3-D space + time) imaging is needed to investigate the developmental cardiac mechanics with high temporal and spatial resolution. We hereby integrated light-sheet fluorescence microscopy (LSFM) with light-field microscopy (LFM), to simultaneously visualize myocardial contractility and intracardiac blood flow in three dimensions at 200 volumes per second (vps). LSFM allows for reconstruction of the myocardial contraction in zebrafish embryo; and LFM enables simultaneous tracking of the blood cells entering and leaving the contracting heart. We herein established particle tracking velocimetry to interrogate the trajectories of intracardiac blood cells, and we demonstrated deformable image registration to reveal a decrease in the myocardial contractility from atrioventricular (AV) canal to the outflow tract (OFT). We imaged myocardium undergoing torsional contraction and blood flow undergoing regurgitation. Taken together, the integration of light-field and light-sheet microscopy, followed by an image-based analysis pipeline, provides the biomechanical insights into coupling myocardial kinetics with rotational contraction along with intracardiac flow dynamics during development.

The online attention is a direct representation of the demand and behavior habits of tourist on the Internet. The daily Baidu Index during a certain period of time with the names of scenic spots as search keywords can indicate the distribution characteristics of the online attention of these scenic spots. The online attention of class 5Ascenic spots in Jiangsu Province shows a precursor effect (having a peak before the holiday starts) during Public Holidays, including the May Day holiday(3days usually beginning from 1st May). While it has a peak during the first three days of National Day holiday(one week usually from 1st to 7th Oct.), consistent with the actual tourist flow. During the whole year, the online attention shows obvious seasonality with 3 peak times

Based on the Baidu search index of key words, this paper builds online search indexes of keywords related to Beijing tourism concerning the six basic elements of one trip– catering, accommodation, traffic, sightseeing, shopping and entertainment. A vector autoregression model is then built with the time serial date of the online search indexes and the actual number of Beijing domestic trips to forecast the latter. It is found that there is a long-term co-integration relationship between the online search indexes data and the number of domestic trips to Beijing. The model constructed has a good prediction ability for Beijing domestic trips.

We demonstrate a deep-learning based light-field microscopy method, which achieves greatly improved spatial resolution and video-rate reconstruction throughput, thereby allowing sustained volumetric recording of fast biological dynamics at high spatiotemporal resolution.

The wedge-shaped oil film thickness, pressure and temperature distribution of the valve plate pair of an axial piston pump were investigated using finite difference and relaxation iterative methods and lubrication characteristics for different working conditions and tilt and non-tilt states of the cylinder block were analysed for comparison. The oil film thickness changed when the cylinder block was tilted relative to the valve plate and produced hydrodynamic effects, increasing the carrying capacity. The structural parameter of the valve plate pair influenced lubrication characteristics. The temperature of the oil film increased and the temperature field was unevenly distributed owing to frictional power–related changes to heat energy. The simulated temperature and friction coefficient showed good agreement with measured values.

The Dengjitun Cu deposit, located in the central Xing’an Block, represents a key target for medium- to large-sized porphyry Cu deposit exploration. The mineralization in this area is closely associated with silicification and propylitic alteration and occurs in a distinctive sequence of quartz-bearing veinlets as well as in a disseminated form within an altered porphyritic granodiorite. In this paper, we present new precise laser ablation inductively coupled plasma mass spectrometry (LA–ICP–MS) U–Pb zircon age data, geochemical data and Hf isotopic data on the porphyritic granodiorite at Dengjitun and use these data to improve our understanding of the Jurassic tectonic evolution of this region. Zircon U–Pb dating of two samples from the porphyritic granodiorite yield Early Jurassic ages of 174.2 ± 1.1 Ma and 173.9 ± 1.1 Ma, which are concordant within error. The Dengjitun porphyritic granodiorite is a high-K calc-alkaline and slightly peraluminous I-type granite. It is enriched in light rare earth elements (LREEs) and large ion lithophile elements (LILEs; e.g., K, Rb, and Ba), depleted in heavy rare earth elements (HREEs; LREE/HREE = 6.43–13.34) and high field strength elements (HFSE; e.g., Nb, Ti, P), and has weak positive Ce anomalies (δCe = 1.15–1.25) and negligible Eu anomalies (δEu = 0.85–0.99). The zircons from the porphyritic granodiorite have positive eHf(t) values (+ 8.7 to +11.7) and elevated 176Hf/177Hf ratios (0.282912–0.283000) that yield young TDM2 ages (428–602 Ma). Collectively, these data indicate that the porphyritic granodiorite formed from primitive magma that was generated by the partial melting of juvenile thickened mafic lower crust, which in turn was originally derived from depleted mantle during the Neoproterozoic. The thickened lower crustal material was metamorphosed under amphibolite- to eclogite-facies conditions at depths of >45 km during the subduction of the Mongol–Okhotsk Ocean, with the resulting magmas assimilating some mantle-derived material prior to emplacement. Combining these data with the tectonic history of this area, we suggest that the Dengjitun porphyritic granodiorite formed in a post-collisional extensional tectonic setting after the Early Jurassic final closure of the Mongol–Okhotsk Ocean.