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The fractional heat operator (partial derivative(t) - &triangle(x))(s) and Continuous Time Random Walks (CTRWs) are interesting and sophisticated mathematical models that can describe complex anomalous systems. In this paper, we prove asymptotic mean value representation formulas for functions with respect to (partial derivative(t) - &triangle(x))(s) and we introduce new nonlocal, nonlinear parabolic operators related to a tug-of-war which accounts for waiting times and space-time couplings. These nonlocal, nonlinear parabolic operators and equations can be seen as nonlocal versions of the evolutionary infinity Laplace operator. (c) 2022 The Author(s). Published by Elsevier Inc....
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The fractional heat operator (partial derivative(t) - &triangle(x))(s) and Continuous Time Random Walks (CTRWs) are interesting and sophisticated mathematical models that can describe complex anomalous systems. In this paper, we prove asymptotic mean value representation formulas for functions with respect to (partial derivative(t) - &triangle(x))(s) and we introduce new nonlocal, nonlinear parabolic operators related to a tug-of-war which accounts for waiting times and space-time couplings. These nonlocal, nonlinear parabolic operators and equations can be seen as nonlocal versions of the evolutionary infinity Laplace operator. (c) 2022 The Author(s). Published by Elsevier Inc.
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To better understand the molecular mechanisms behind plant growth and leaf senescence in monocot plants, we identified a mutant exhibiting dwarfism and an early-senescence leaf phenotype, termed dwarf and early-senescence leaf1 (d...
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To better understand the molecular mechanisms behind plant growth and leaf senescence in monocot plants, we identified a mutant exhibiting dwarfism and an early-senescence leaf phenotype, termed dwarf and early-senescence leaf1 (del1). Histological analysis showed that the abnormal growth was caused by a reduction in cell number. Further investigation revealed that the decline in cell number in del1 was affected by the cell cycle. Physiological analysis, transmission electron microscopy, and TUNEL assays showed that leaf senescence was triggered by the accumulation of reactive oxygen species. The DEL1 gene was cloned using a map-based approach. It was shown to encode a pectate lyase (PEL) precursor that contains a PelC domain. DEL1 contains all the conserved residues of PEL and has strong similarity with plant PelC. DEL1 is expressed in all tissues but predominantly in elongating tissues. Functional analysis revealed that mutation of DEL1 decreased the total PEL enzymatic activity, increased the degree of methylesterified homogalacturonan, and altered the cell wall composition and structure. In addition, transcriptome assay revealed that a set of cell wall function- and senescence-related gene expression was altered in del1 plants. Our research indicates that DEL1 is involved in both the maintenance of normal cell division and the induction of leaf senescence. These findings reveal a new molecular mechanism for plant growth and leaf senescence mediated by PECTATE LYASE-LIKE genes.
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The existing automatic parking algorithms often neglect the unknown obstacles in the parking environment, which causes a hidden danger to the safety of the automatic parking system. Therefore, this paper proposes parking space det...
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The existing automatic parking algorithms often neglect the unknown obstacles in the parking environment, which causes a hidden danger to the safety of the automatic parking system. Therefore, this paper proposes parking space detection and path planning based on the VIDAR method (vision-IMU-based detection and range method) to solve the problem. In the parking space detection stage, the generalized obstacles are detected based on VIDAR to determine the obstacle areas, and then parking lines are detected by the Hough transform to determine the empty parking space. Compared with the parking detection method based on YOLO v5, the experimental results demonstrate that the proposed method has higher accuracy in complex parking environments with unknown obstacles. In the path planning stage, the path optimization algorithm of the A* algorithm combined with the Bezier curve is used to generate smooth curves, and the environmental information is updated in real time based on VIDAR. The simulation results show that the method can make the vehicle efficiently avoid the obstacles and generate a smooth path in a dynamic parking environment, which can well meet the safety and stationarity of the parking requirements.
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With the rapid increase in vehicle ownership, exhaust pollution has become one of the important sources of air pollution in China. In this study, a MAHA METDH 6.3 exhaust gas test experimental platform was developed, and an emissi...
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With the rapid increase in vehicle ownership, exhaust pollution has become one of the important sources of air pollution in China. In this study, a MAHA METDH 6.3 exhaust gas test experimental platform was developed, and an emission model suitable for coupling with real-time road conditions was established based on large-scale vehicle emission test data. Based on traffic big data such as traffic volume, average vehicle speed, and vehicle model distribution, ArcGIS was used to select the road network information in the study area and combined with the emission model to realize the spatial distribution of line sources of vehicle emissions. Finally, based on the road network simulation model built by VISSIM, the emission changes caused by the two measures of trunk line optimization and new energy vehicle development were simulated and analyzed. The results show that the spatial distribution characteristics of vehicle exhaust pollutants in Zhangdian District are closely related to road type. Taking trunk line optimization measures and developing new energy vehicles have a certain reduction effect on vehicle emissions in Zhangdian District. This study lays a foundation for proposing targeted measures to reduce motor vehicle emissions based on big traffic operation data.
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Integrated control systems for vehicle-handling stability are usually based on the steering bifurcation mechanism. The best integrated control performance is obtained by coordinating different control methods. However, in vehicle ...
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Integrated control systems for vehicle-handling stability are usually based on the steering bifurcation mechanism. The best integrated control performance is obtained by coordinating different control methods. However, in vehicle steering and driving conditions, the coupling characteristics of the longitudinal forces and the lateral forces of the tyres must lead to changes in the bifurcation characteristics. The corresponding vehicle dynamics stability region has to be redetermined. The corresponding integrated control method also needs to be adjusted. Therefore, in combination with the physical significance of the dynamics equilibrium point of the vehicle system, the definition of the driving stability region of the vehicle based on the characteristics of the driving torque and the steering angle bifurcation is proposed. With the concept presented above, the five-degree-of-freedom non-linear vehicle system model for the driving stability region of the vehicle was solved. The simulation results show that, according to the driving stability region of the vehicle, the vehicle dynamics stability with different driving torque inputs and different front-wheel steering-angle inputs can be accurately estimated. The study of the driving stability region of the vehicle is beneficial for engineering applications in non-linear automotive dynamics research. In addition, it provides the theoretical basis for integrated control of the vehicle-handling stability.
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Due to the ecotoxicity of 17β-estradiol (E2), residual E2 in the environment poses potential risks to human and animal health and ecosystems. Biodegradation is considered one of the most effective strategies to remove E2 from the...
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Due to the ecotoxicity of 17β-estradiol (E2), residual E2 in the environment poses potential risks to human and animal health and ecosystems. Biodegradation is considered one of the most effective strategies to remove E2 from the environment. Here, a novel, efficient E2-degrading bacterial strain Microbacterium resistens MZT7 was isolated from activated sludge and characterized. The genome of strain MZT7 contained 4,011,347 bp nucleotides with 71.26% G + C content and 3785 coding genes. There was 86.7% transformation efficiency of 10 mg/L E2 by strain MZT7 after incubation for 5 d at optimal temperature (30 °C) and pH (7.0). This strain was highly tolerant to ranges in pH (5.0–11.0), temperature (20–40 °C), and salinity (2–8%). Adding sources of carbon (glucose, maltose, sucrose, or lactose) or nitrogen sources (urea, peptone, or beef extract) promoted the degradation of E2 by strain MZT7. However, when yeast extract was added as a nitrogen source, the degradation efficiency of E2 was inhibited. Metabolites were analyzed by LC-MS and three metabolic pathways of E2 degradation were proposed. Further, the intermediates dehydroepiandrosterone and androsta-1,4-diene-3,17-dione were detected, as well as identification of kshB and fadD3 genes by KEGG, confirming one E2 degradation pathway. This study provided some insights into E2 biodegradation.
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Buses represent the main mode for intercity passenger transportation in China. In recent years, a multichannel ticketing strategy has been widely employed in the bus passenger transportation industry. However, the mechanisms and k...
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Buses represent the main mode for intercity passenger transportation in China. In recent years, a multichannel ticketing strategy has been widely employed in the bus passenger transportation industry. However, the mechanisms and key drivers of the channels through which bus passengers purchase tickets are underexplored. Thus, the aim of this study is to empirically apply an integrated choice and latent variable (ICLV) approach to analyze ticketing channel choice behavior and the heterogeneous preferences of bus passengers. The variables incorporated in the model include the socioeconomic characteristics of passengers, trip attributes, and latent attitudes with 12 ordinal indicators. Based on the data of 1800 participants collected from the city of Beijing, China, this study develops a ticketing channel choice ICLV model merging a discrete choice model with a structural equation model. The key factors that affect the channel preference are further discussed through a comparison with a conventional multinomial logit (MNL) model. The results reveal that the three attitudinal variables have a significant influence on ticketing channel choice. Furthermore, this study indicates that perceptual differences exist due to various socioeconomic and trip characteristics. Personal privacy is a major obstacle that prevents passengers from choosing online channels, especially for older passengers and those with lower education.
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Chlorophyll (Chl) b is a ubiquitous accessory pigment in land plants, green algae, and prochlorophytes. This pigment is synthesized from Chl a by chlorophyllide a oxygenase and plays a key role in adaptation to various environment...
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Chlorophyll (Chl) b is a ubiquitous accessory pigment in land plants, green algae, and prochlorophytes. This pigment is synthesized from Chl a by chlorophyllide a oxygenase and plays a key role in adaptation to various environments. This study characterizes a rice mutant, pale green leaf (pgl), and isolates the gene PGL by using a map-based cloning approach. PGL, encoding chlorophyllide a oxygenase 1, is mainly expressed in the chlorenchyma and activated in the light-dependent Chl synthesis process. Compared with wild-type plants, pgl exhibits a lower Chl content with a reduced and disorderly thylakoid ultrastructure, which decreases the photosynthesis rate and results in reduced grain yield and quality. In addition, pgl exhibits premature senescence in both natural and dark-induced conditions and more severe Chl degradation and reactive oxygen species accumulation than does the wild-type. Moreover, pgl is sensitive to heat stress.
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This paper investigates how expressions of emotion affect persuasiveness when the expresser and the recipient have different levels of power. The first study demonstrates that when the recipient overpowers the expresser, emotional...
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This paper investigates how expressions of emotion affect persuasiveness when the expresser and the recipient have different levels of power. The first study demonstrates that when the recipient overpowers the expresser, emotional expressions reduce persuasion. A second study reveals that power and perceived appropriateness of emotional expressions independently moderate the effect of emotional expressions. Emotional expressions hamper persuasion when the recipient overpowers the expresser, or when the emotional expressions are considered inappropriate.
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Activation of mammalian target of rapamycin (mTOR) signaling pathway is associated with poor prognosis of epithelial ovarian cancer. The TSC1-TSC2 complex is a critical negative regulator of mTOR signaling. Here, we demonstrated t...
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Activation of mammalian target of rapamycin (mTOR) signaling pathway is associated with poor prognosis of epithelial ovarian cancer. The TSC1-TSC2 complex is a critical negative regulator of mTOR signaling. Here, we demonstrated that TSC1 was frequently downregulated in high-grade serous ovarian carcinoma (HGSOC) and low TSC1 expression level is associated with advanced tumor stage. We next identified miR-130a to be a negative regulator of TSC1 by targeting its 3'UTR. miR-130a was overexpressed in HGSOC and could drive proliferation and invasion/metastasis of ovarian cancer cells. miR-130a could also attenuate rapamycin/starvation-induced autophagy. Ectopic TSC1 expression could block the effects of miR-130a on cell proliferation, migration and autophagy. Finally, we found that miR-130a expression could be upregulated by inflammatory factors and was transactivated by NF-kappa B. Therefore, our findings establish a crosstalk between inflammation and mTOR signaling that is mediated by miR-130a, which might have a pivotal role in the initiation and progression of HGSOC.
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