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Urban forest parks serve as significant venues for tourists' leisure and recreation. The experiences and perceptions of tourists in these parks considerably influence their attitudes and behaviors. While numerous studies have investigated the functions and values of urban forest parks at a macro level, the mechanisms influencing tourists' perceived values and their environmentally responsible behavior at a micro level remain under explored. This research used structural equation modeling (SEM) to test the association between tourists' perceived values and their environmentally responsible behavior, including the mediating functions of tourists' satisfaction and their subjective well-being. 502 valid questionnaires in total were obtained from Changpoling National Forest Park in Guiyang City, Guizhou, China, for this case study. The results show that there are some variances in the impact of the dimensions of tourists' perceived value on environmentally responsible behavior, in which service quality, resource quality, and emotional value impose a pronounced positive effect on environmentally responsible behavior, tourism costs impose a pronounced negative effect on environmentally responsible behavior, and the activity experience does not exert a pronounced effect on environmentally responsible behavior. Satisfaction and subjective well-being have a mediating function during the process of positive influence of tourists' perceived value on their environmentally responsible behavior and serve as partial mediators, and the significant positive influence of satisfaction on subjective well-being as well as subjective well-being on environmentally responsible behavior are verified. This research can help better explain the mechanism of the effect of tourists' perceived value exerted on environmental responsibility behavior in nature-based tourism destinations, and also has a guiding and reference significance for the sustainable development of urban forest parks. [ABSTRACT FROM AUTHOR]

Anthocyanin is one important nutrition composition in Tartary buckwheat (Fagopyrum tataricum) sprouts, a component missing in its seeds. Although anthocyanin biosynthesis requires light, the mechanism of light-induced anthocyanin accumulation in Tartary buckwheat is unclear. Here, comparative transcriptome analysis of Tartary buckwheat sprouts under light and dark treatments and biochemical approaches were performed to identify the roles of one B-box protein BBX22 and ELONGATED HYPOCOTYL 5 (HY5). The overexpression assay showed that FtHY5 and FtBBX22 could both promote anthocyanin synthesis in red-flower tobacco. Additionally, FtBBX22 associated with FtHY5 to form a complex that activates the transcription of MYB transcription factor genes FtMYB42 and FtDFR, leading to anthocyanin accumulation. These findings revealed the regulation mechanism of light-induced anthocyanin synthesis and provide excellent gene resources for breeding high-quality Tartary buckwheat. [ABSTRACT FROM AUTHOR]

Kandelia obovata (Rhizophoraceae) is the most cold-tolerant mangrove species and has been widely used in coastal wetland ecological restoration due to its specific viviparous phenomenon, beautiful shape, and unique floral pattern. Due to long-term adaptation to their local environment, the phenotypic characteristics and stress resistance of widely distributed plants of the same species often differentiate across different locations. The capacity for cold resistance is closely linked to the physiological and structural characteristics of plants. Herein, we explored the temporal variations in the leaf structure and physiological status of K. obovata under −5.5 °C from different areas such as Jiulongjiang Estuary (JLJ, 24°25′ N), Fujian Province, and Longgang City (LG, 27°34′ N) and Jiaojiang District (JJ, 28°67′ N), Zhejiang Province. The morphological variations implied that the cold resistance of K. obovata obviously strengthened after the northward migration and acclimatization, in the following order: LG > JJ > JLJ. More specifically, after exposure to a sustained low temperature, the relative conductivity (REC), an index widely used to evaluate the degree of plant damage, remarkably increased from 33.62 ± 2.39 to 63.73 ± 3.81, 31.20 ± 1.63 to 49.48 ± 1.12, and 23.75 ± 0.13 to 54.24 ± 1.45 for JLJ, LG, and JJ, respectively (p < 0.05). Additionally, the palisade-to-spongy tissue ratio (P/I) of JLJ and JJ decreased from 0.78 ± 0.05 and 0.75 ± 0.03 to 0.5 ± 0.04 and 0.64 ± 0.02 (p < 0.05), whereas no significant changes were found in LG (p > 0.05). The SOD activity of LG significantly kept increasing, with values increased from 352.49 ± 10.38 to 477.65 ± 1.78 U·g−1, whereas no apparent changes in JLJ and JJ were observed with the sustained low temperature. The results of this study improved our understanding of the response of K. obovata to freezing stress, which could provide a sound theoretical foundation for cultivating cold-resistant varieties, as well as expanding mangrove plantations in higher latitudes. [ABSTRACT FROM AUTHOR]

A stitching linear scan method is proposed for roundness and diameter measurement of small cylindrical workpieces instead of the conventional rotary scan method due to the crucial alignments of eccentricity and inclination. To verify the reliability of the proposed method, by which the coordinates of the cross-sectional circle of a small cylinder is divided into several equal parts to be obtained and reconstructed, the diameter and roundness measurement uncertainties of the small cylinders with a diameter 1.5 mm are evaluated to be 0.047 μm and 0.095 μm, respectively, which can meet the uncertainty target of 0.1 μm. To investigate the measurable dimension by the proposed method, measurement uncertainty analysis of the small cylinders with various dimensions has been conducted according to the previous evaluation, since all the procedures are the same except for the uncertainty of X coordinates, which changes with the measured dimension's change. The results show that the small cylinders with a diameter range from 0.01 mm to 50 mm can be measured by the proposed method when the position error θZ is reduced to the corresponding value. There is no measuring limitation set by the proposed model theoretically in the case of θX = θZ = 0.1°, while the machine has a measuring limitation. [ABSTRACT FROM AUTHOR]

Tartary buckwheat (Fagopyrum tataricum Gaertn.) belongs to the family of Polygonaceae and is used as a multi-functional plant. R2R3-MYB transcription factors play a crucial part in plant growth and are involved in many biological processes where they regulate their internal environment. To date, there is no documented systematic research on the R2R3-MYB gene family in Tartary buckwheat. Here, domain features, chromosomal location, motif prediction, gene structure, cis-acting elements, as well as the expression pattern of R2R3-MYB transcription factors were analyzed comprehensively in Tartary buckwheat using a bioinformatic approach. Additionally, one R2R3-MYB gene was verified by transgenic Arabidopsis. Results indicate that a total of 152 R2R3-MYB genes were identified with special R2R3 domains and were distributed on 8 chromosomes of Tartary buckwheat. They were further classified into 25 sub-categories via phylogenetic analysis in terms of the R2R3-MYB gene family classification principles of Arabidopsis thaliana. This classification was further supported by analysis of exon–intron structure, motif, and cis-elements. Tandem and segmental duplication existed among the R2R3-MYB gene family of Tartary buckwheat, and there were 5, 8, 27, and 36 FtR2R3-MYB homologous genes, respectively, when comparing with Zea mays, Oryza sativa, Arabidopsis thaliana, and Solanum melongena by synteny analysis. The expression pattern of FtR2R3-MYB genes in different tissue and under salt stress and different light condition showed that members had tissue-specific expression levels and that these members may play diverse functions in plant growth and adaptation to varying environments. In addition, one of the FtR2R3-MYB gene families, FtMYB43, a homologue of AtTT2, clustered with R2R3-MYB from other plant species, which were reported to be involved in the regulation of anthocyanin or proanthocyanidin biosynthesis. This gene was located in the nucleus, and had transcriptional activation activity, indicating that FtMYB43 may be a positive transcript factor of anthocyanin or proanthocyadin biosynthesis. Moreover, the function of FtMYB43 was further verified to improve the production of anthocyanin in transgenic Arabidopsis by overexpression, and qRT-PCR assay implied that FtMYB43 may regulate the expression levels of most structural genes of the anthocyanin biosynthesis pathway in Arabidopsis seedlings. These results provide more insights into the structure and function of the R2R3-MYB gene family and may accelerate the breeding of ornamental buckwheat cultivars. [ABSTRACT FROM AUTHOR]

In recent years, lattice structures produced via additive manufacturing have been increasingly investigated for their unique mechanical properties and the flexible and diverse approaches available to design them. The design of a strut with variable cross-sections in a lattice structure is required to improve the mechanical properties. In this study, a lattice structure design method based on a strut cross-section composed of a mixture of three ellipses named a tri-directional elliptical cylindrical section (TEC) is proposed. The lattice structures were fabricated via the selective laser melting of 316L alloy. The finite element analysis results show that the TEC strut possessed the high mechanical properties of lattice structures. Compression experiments confirmed that the novel lattice structure with the TEC strut exhibited increases in the elastic modulus, compressive yield strength, and energy absorption capacity of 24.99%, 21.66%, and 20.50%, respectively, compared with the conventional lattice structure at an equal level of porosity. [ABSTRACT FROM AUTHOR]

Non-circular gears have the characteristics of gear ratio accuracy, good dynamic performance, and wide application prospects but are difficult to manufacture. Wire electrical discharge machining (WEDM) can process almost all kinds of non-circular gear. In order to solve the problem that the process parameters are mainly adjusted using the operator's experience and to improve the surface quality of non-circular gears machined using WEDM, this research took Pascal gears processed with a fast-walking WEDM machine as the object, conducted orthogonal tests, and used hybrid particle swarm optimization (HPSO) to optimize support vector regression (SVR) with different kernel functions, to predict various surface integrity indicators. The results showed that the rbf kernel function had a better performance in the prediction model of surface integrity indicators, which can provide a reference for the parameter selection of non-circular gear machining using WEDM. The final predicted results were R2 = 0.9978, MAPE = 0.4534 for surface roughness, R2 = 0.9483, MAPE = 3.1673 for surface residual stress, and R2 = 0.9786, MAPE = 0.4779 for surface microhardness. [ABSTRACT FROM AUTHOR]

For an electro-hydrostatic actuator (EHA), the position, speed, and current cascade three-loop control architecture are dominant in existing active disturbance rejection control (ADRC). However, this architecture suffers from many problems, such as severe noise sensitivity of the extended state observer (ESO), excessive complexity of control structure, and too many tuned parameters, which makes the controller not easy to implement in practice. Aiming at the above drawbacks, a novel cascade double-loop ADRC strategy that is automatic current-constrained is proposed, which makes the whole ADRC architecture simplified to the position and the integrated speed–current double-loop architecture. Firstly, for the position control loop, the singular perturbation theory is used to reasonably reduce the order of the model for the position subsystem of EHA. A reduced order ADRC controller (ROADRC) is synthesized, which not only effectively reduces the noise sensitivity of ESO, but also circumvents use of the actuation acceleration information in the controller design process. Secondly, the integrated speed–current ADRC controller is designed by taking the speed and current subsystems of EHA into synthesis, which avoids the problem of excessive current loop bandwidth in conventional three-loop control architecture, and the number of tuned parameters is significantly reduced. Additionally, an uncomplicated and effective automatic current-constrained ADRC controller (CACADRC) is designed to solve the problem in the integrated speed–current ADRC that the current cannot be automatically constrained. Finally, by comparing the three-loop PI controller with the traditional three-loop ADRC, a detailed simulation analysis is carried out to verify the effectiveness and merits of the proposed controller. The simulation results show that the proposed controller not only inherits the advantages of high precision and strong disturbance rejection performance of the conventional ADRC, but can also efficiently decrease the noise sensitivity of ESO and effectively achieve the current-constrained control. [ABSTRACT FROM AUTHOR]

Tartary buckwheat (Fagopyrum tataricum Gaertn.) is a coarse cereal with strongly abiotic resistance. The MYB family plays a regulatory role in plant growth, development, and responses to biotic and abiotic stresses. However, the characteristics and regulatory mechanisms of MYB transcription factors in Tartary buckwheat remain unclarified. Here, this study cloned the FtMYB22 gene from Tartary buckwheat, and investigated its involvement in responding to individual water deficit and salt stress in Arabidopsis. Sequence analysis highlighted that the N-termini of FtMYB22 contained two highly conserved SANT domains and one conserved domain from the SG20 subfamily. Nucleus-localized FtMYB22 did not have individual transcriptional activation activity. Water deficiency and salt stress induced the high expression of the GUS gene, which was driven by the promoter of FtMYB22. Yeast stress experiments showed that the overexpression of FtMYB22 significantly reduced the growth activity of transgenic yeast under water deficit or salt stress. Consistently, the overexpression of FtMYB22 reduced the salt and water deficit stress resistance of the transgenic plants. In addition, physiological parameters showed that transgenic plants had lower proline and antioxidant enzyme activity under stress conditions. Compared to the wild-type (WT), transgenic plants accumulated more malondialdehyde (MDA), H2O2, and O2−; they also showed higher ion permeability and water loss rates of detached leaves under stress treatments. Notably, FtMYB22 was involved in plant stress resistance through an ABA-dependent pathway. Under stress conditions, the expression of RD29A, RD29B, PP2CA, KIN1, COR15A, and other genes in response to plant stress in transgenic lines was significantly lower than that in the WT (p < 0.05). Furthermore, yeast two-hybrid assay showed that there was a significant interaction between FtMYB22 and the ABA receptor protein RCAR1/2, which functioned in the ABA signal pathway. Altogether, FtMYB22, as a negative regulator, inhibited a variety of physiological and biochemical reactions, affected gene expression and stomatal closure in transgenic plants through the ABA-dependent pathway, and reduced the tolerance of transgenic Arabidopsis to water deficiency and salt stress. Based on these fundamental verifications, further studies would shed light on the hormone signal response mechanism of FtMYB22. [ABSTRACT FROM AUTHOR]

In recent years, the lattice structure produced by additive manufacturing is a type of metal foam that has been increasingly investigated for its unique mechanical properties. However, the conventional Computer-Aided Design (CAD) is inefficient, the triply periodic minimal surfaces are rarely mixed, and the smooth transitions at the boundaries are not considered. In this study, a hybrid optimization design method based on implicit surfaces is proposed, which combines multiple implicit surfaces to achieve the continuous change in the curvature at the structure junctions and reduce the stress concentration. The hybrid lattice structures designed by this method were additively manufactured using 316L alloy via a selective laser melting. The results of the finite element analysis and mechanical compression test show that the hybrid lattice structures generated by this method exhibit a higher yield strength and energy absorption. These works can be used for other implicit surfaces, improve and enrich the types of implicit surfaces, and provide more good choices for practical applications. [ABSTRACT FROM AUTHOR]

Nickel oxide (NiO) nanotubes were synthesized via a thermal oxidation process from Ni nanowires. The effects of oxidation temperature on the morphology, microstructures, and composition of nanowires were investigated using scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The results show that the Ni nanowires convert initially to Ni/NiO core-shell nanowires with increasing annealing temperatures, and then to the nanotubes at the critical transition temperature of about 425 °C. Our findings provide useful information for the preparation of NiO nanotubes to meet the required applications. [ABSTRACT FROM AUTHOR]

The exponential increase in online reviews and recommendations makes document classification and sentiment analysis a hot topic in academic and industrial research. Traditional deep learning based document classification methods require the use of full textual information to extract features. In this paper, in order to tackle long document, we proposed three methods that use local convolutional feature aggregation to implement document classification. The first proposed method randomly draws blocks of continuous words in the full document. Each block is then fed into the convolution neural network to extract features and then are concatenated together to output the classification probability through a classifier. The second model improves the first by capturing the contextual order information of the sampled blocks with a recurrent neural network. The third model is inspired by the recurrent attention model (RAM), in which a reinforcement learning module is introduced to act as a controller for selecting the next block position based on the recurrent state. Experiments on our collected four-class arXiv paper dataset show that the three proposed models all perform well, and the RAM model achieves the best test accuracy with the least information. [ABSTRACT FROM AUTHOR]

Hereditary spastic paraplegia (HSP) is one of the most genetically heterogeneous neurological disorders. HSP is classified as pure when only a spastic weakness of the lower extremities is present. Complex HSP comes with additional neurological or systemic abnormalities. Complex HSP with skeletal abnormalities is rare and mostly seen in autosomal recessive HSP. Autosomal dominant (AD) complex HSP with skeletal abnormalities are consistently seen only in SPG9 (spastic gait type 9). In this paper, we report a kindred condition with AD HSP among four living affected individuals who had progressive, adult onset spastic paraparesis that was associated with a distal arthrogryposis (DA) in every affected individual. They also had episodes of rhabdomyolysis without any clinical signs of myopathy. Exhaustive genetic analysis including targeted sequencing of known HSP and DA genes and whole exome sequencing did not identify the disease-causing gene. It excluded all known HSP and DA genes. We propose that this is a novel genetic type of complex AD HSP. Elucidation of a genetic cause of this type of HSP will further contribute to our understanding of axonal degeneration and skeletal abnormalities. [ABSTRACT FROM AUTHOR]