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Urban parks, a public product and service, can provide ecological, social, cultural, and recreational resources essential for sustainable urban development. Park attributes are valuable indicators for evaluating parks, and park planning and management personnel must consider visitors' perceptions of these attributes. However, previous studies often ignored or underestimated negative attributes, especially in high-rating reviews. Moreover, parks have multiple attributes, rather than a singular one, and there exist potential associations among these attributes. Here, we selected 63 urban parks in Park City, Chengdu, China, as a case study; we used online reviews from Ctrip and Dianping, and Latent Dirichlet Allocation (LDA) combined with a manual coding method to explore visitors' perceptions (positive or negative) of each attribute in each review. Initially, we analyzed how park attributes affected overall dissatisfaction using multiple linear regressions, and counted the positive and negative attributes in each review rating. We then measured the association rules between various attributes and perceptions. We found that both positive and negative attributes (84.12% and 54.86%) mainly appear in high-rating reviews, while low ratings accounted for only 15.69% of negative attributes. Attributes in high-rating reviews were more generalized and had a more significant effect than in low-rating. Additionally, three association rules were identified, including cases where two positive attributes (11 instances), two negative attributes (6 instances), or one negative and one positive attribute appeared together (2 instances), all within the cultural and historical attributes category. This study's outcomes contribute novel insights to the realm of sustainable urban park planning and management. • Negative attributes lead to dissatisfaction in different review rating. • Negative attributes in high-rating reviews are impactful and generalized. • Associations rule between various park attributes. • Combined Latent Dirichlet Allocation with manual coding approach. [ABSTRACT FROM AUTHOR]

[Display omitted] • ZnO@NH 2 -MIL-88B has good degradation performance for a variety of organic pollutants. • Simultaneous degradation and removal of multiple organic pollutants by ZMFe-3. • Three degradation pathways of MB were predicted by DFT calculations and LC-MS. • ZnO@NH 2 -MIL-88B forms a fast electron transfer channel. Combining photocatalysts with Fenton technology can improve the catalytic properties of materials and achieve efficient degradation of organic pollutants. However, preparing low-cost catalysts using simple methods remains a challenge. This paper selected a more environmentally friendly and cost-effective semiconductor material, zinc oxide, for the modification of NH 2 -MIL-88B and prepared a new S-scheme heterojunction photo-Fenton catalyst ZnO@NH 2 -MIL-88B (ZMFe-x) by a simple solvothermal method. Moreover, the Zn-O-Fe bonds that were formed between the interfaces enabled a fast channel for the photoelectron transport that was created by photoexcitation from the ZnO conduction band to the NH 2 -MIL-88B valence band. This allowed the ZMFe-x catalysts to have better removal performance for organic pollutants in the photo-Fenton reaction. The dominating role of hydroxyl radicals in the degradation procedure was determined by ESR analysis and free radical trapping experiments, and the degradation mechanisms and pathway of contaminants were predicted by intermediate analysis and DFT calculations. This study provides a stable and effective new strategy for preparing MOFs catalysts for removing various pollutants. [ABSTRACT FROM AUTHOR]

The intricate pollutant composition and pronounced water fluctuations of Chinese liquor brewing wastewater (CLBW) pose formidable challenges for effective treatment, thereby raising significant environmental concerns. This study for the first time delves into the exploration of algal–bacterial granular sludge (ABGS) development and its efficacy in the removal of organic matter and nitrogen and phosphorus over a 100–day investigation of real CLBW treatment. Mature ABGS emerged after approximately 40 days of treating wastewater with 20% real CLBW, exhibiting exceptional settling performance and significant removal of COD (86.2%), NH 4 +–N (98.0%), and TP (51.5%). As the real CLBW proportion increased to 40% or higher, a stable granular structure and excellent settleability persisted, primarily attributed to the consistent content of tightly bound extracellular polymeric substances, the sustained protein–to–polysaccharide ratio, and the proliferation of microalgae within the granules. Microbial community analysis revealed the dominance of microalgal species, including Sphaeropleales , Scenedesmaceae , and Chloromonas. Moreover, the observed decline in nitrification efficiency with increasing CLBW ratio was linked to reductions in Nitrosomonas and Nitrospira populations. Conversely, the recovered TN removal was primarily associated with the accumulation of denitrifiers, including Azoarcus and Thauera , especially when the real CLBW ratio reached 100%. The findings from this study are anticipated to offer a practical reference for optimizing and promoting the treatment of real CLBW. [Display omitted] • Mature ABGS was established within 40 days of treating 20% real CLBW. • Granular structure and settling ability maintained during the extended operation. • Declined COD and N but steady TP removal rates were observed with ≥40% CLBW. • TB-EPS content and PN/PS of ABGS were constant despite the increased CLBW ratio. • Accumulation of denitrifiers in granules contributed to the recovery of TN removal. [ABSTRACT FROM AUTHOR]

Originated from the future trends and requirements for silicone rubber (SR) in harsh work condition of advanced cutting-edge fields (construction, aerospace, marine equipment and automobile, etc), the processing complexity, complex ingredients and unbalanced overall properties of traditional multi-component flame-retarding SR system are limited. The development of mono-component and halogen-free flame retardants with adequate efficiency, durability and strength have been urgently expected for settling the crucial bottleneck issue of SR materials, which can avoid the defects of performance contradictions for long-used multi-component system in previous published work. Under such background, this paper has fabricated a hydrophobic Mn-doped melamine phosphate (H-DTMA@Mn) via facile multi-stage construction strategy that has been confirmed by a series of characterizations. The results have indicated that SR/28 phr H-DTMA@Mn can achieve limiting oxygen index (LOI) of 32.4% and UL-94 V-0 rating. Along with the reduced peak heat release rate, the validity of as-prepared H-DTMA@Mn for raising the flame retardancy of SR has been straightway clarified. Different from the previous work, the prominent flame retardant durability of SR/H-DTMA@Mn in many extreme environment can be maintained via the protection action of hydrophobic structure. The detailed analysis on char residues of SR composites can explain the effective flame retardant mechanism in view of chemical composition and microscopic morphology. Moreover, the mechanical strength and thermal properties of SR composites are ideal and accommodated that are greatly required in the real-life application. To sum up, the desirable balance for comprehensive performance can be realized by introducing the mono-component flame retardants, which can innately open up the innovation for meeting the requirements of SR materials in more fields. • Mono-component and Mn-doped flame retardants were fabricated for SR. • SR/28 phr H-DTMA@Mn can gain 32.4% LOI value and UL‐94 V‐0 rating. • PHRR and THR reduction of SR/28 phr H-DTMA@Mn are 42.3% and 34.7%. • Excellent balance among comprehensive properties of SR composites can be achieved. • Multi-channel synergistic flame retardant mechanism is preliminarily deduced. [ABSTRACT FROM AUTHOR]

Autophagy is an essential degradation and recycling process that maintains cellular homeostasis during stress or nutrient deprivation. However, certain types of tumors such as pancreatic cancers can circumvent autophagy inhibition to sustain growth. The mechanism that autophagy-deficient pancreatic ductal adenocarcinoma (PDAC) uses to grow under nutrient deprivation is poorly understood. Our data show that nutrient deprivation in PDAC results in UDP-glucose dehydrogenase (UGDH) degradation, which is dependent on autophagic cargo receptor sequestosome 1 (p62). Moreover, we demonstrate that accumulated UGDH is indispensable for autophagy-deficient PDAC cells proliferation by promoting hyaluronic acid (HA) synthesis upon energy deprivation. Using an orthotopic mouse model of PDAC, we find that inhibition of HA synthesis by targeting UGDH in PDAC reduces tumor weight. Thus, the combined inhibition of HA and autophagy might be an attractive strategy for PDAC treatment. [Display omitted] • UGDH is degraded by autophagic process dependent on p62 • Autophagy-deficient PDAC upregulates UGDH to promote hyaluronic acid synthesis • Hyaluronic acid maintains autophagy-deficient PDAC proliferation under nutrient starvation Fan et al. report that UGDH is degraded by p62-mediated autophagy, and it accumulates in autophagy-deficient PDAC. UGDH increases hyaluronic acid (HA) synthesis to sustain proliferation of autophagy-deficient PDAC. The combined inhibition of UGDH/HA with autophagy results in reduction of PDAC growth. [ABSTRACT FROM AUTHOR]

This study investigated a rotation-matrix-based finite-time trajectory tracking problem for autonomous underwater vehicles (AUVs) in the presence of output constraints, input quantization, and uncertainties. First, a rotation matrix-based attitude representation is introduced, which allow attitude dynamics to be globally and uniquely represented without unwinding. To satisfy the finite-time stability of AUV tracking control and the output constraints imposed by introducing the new attitude error vector, a novel finite-time command-filtered backstepping controller (FTCFBC) is proposed based on the asymmetrical time-varying barrier Lyapunov function (TVBLF). Subsequently, a second-order auxiliary dynamic system (ADS) is proposed to estimate the negative effects that of input quantization errors. Because the quantized control inputs can be switched at an appropriate earlier or later switching timing depending on the output of the ADS, the negative impact of quantization errors on the control accuracy is reduced. Moreover, an adaptive finite-time disturbance observer (AFTDO) is developed to estimate the lumped uncertainties without prior information on the bounds of the uncertainties. Finally, the results of the theoretical analysis verified that the tracking errors can converge within a finite time. Numerical simulations confirmed the effectiveness of the proposed control scheme. • A second-order auxiliary dynamic system to address quantization errors. • The equilibrium of the virtual errors is always kept within the constraints. • An adaptive finite-time disturbance observer without prior information. • The simplified rotation matrix-based controller avoids the unwinding phenomenon. [ABSTRACT FROM AUTHOR]

To increase the service life of composite materials, self-healing, and damage detection are essential. Although a lot of research has been done on self-healing and damage-reporting materials, it is still difficult to combine self-healing with in-situ and real-time damage detection in bulk resin and composites. By integrating extrinsic self-healing based on microcapsules and internal self-healing based on coordination interaction, the simultaneous self-healing of matrix and interface damage of fiber-reinforced composites was achieved in this study. Specifically, two-component microcapsules filled with epoxy/mercaptan repair agent were inserted into the matrix and Ag nanoparticles (AgNPs) were introduced into the surface of carbon fiber by electroless plating. Upon the rupture of microcapsules, matrix self-healing was used to reach a desirable level of synchronous healing efficiency. In the meantime, the excess sulfhydryl reacted with AgNPs on the fibers to establish a coordination bond for interface self-healing. More intriguingly, the high exothermic action of epoxy resin and mercaptan repair agent in the self-healing process was observed when using infrared thermal imaging technology for in-situ and real-time damage detection. [Display omitted] [ABSTRACT FROM AUTHOR]

• A theoretical model was developed to explain how PRG bolts maintain support force after creep in the anchoring section. • Indoor experiments using Distributed Optical Sensing (DOS) technology revealed the changes in axial force distribution over time for both PR and PGR bolts during service. • The mechanical properties of PR and PGR bolts after long-term loading were evaluated through mechanical testing. As an effective solution for controlling deformation in surrounding rock, prestressed rock bolts have been increasingly adopted in transportation tunnels. However, the potential for prestress loss and anchorage failure due to creep in the anchorage material over extended service life necessitates further investigation. In response, this study investigated the long-term mechanical performance of a prestressed post-grouting resin bolt, focusing on its supporting effect and mechanical behavior after anchorage creep. We began by establishing a model that explained the mechanical mechanism of the grouting segment. This model was then used to analyze the impact of grouting material properties. Additionally, the bearing characteristics of the prestressed post-grouting resin rock bolt during reloading were assessed. Furthermore, a laboratory experiment was conducted using distributed optical fiber strain sensing (DOS) technology to evaluate the long-term behavior and mechanical performance of both prestressed resin anchor bolts (PR bolts) and prestressed post-grouting resin anchor bolts (PGR bolts) under various loading conditions. The results indicated that the PGR bolt significantly reduced prestress loss compared to the PR bolt, with reductions of 13%, 15%, and 16% at pretensions of 50 kN, 80 kN, and 110 kN, respectively. Additionally, PGR bolts can avoid stress concentration on the anchoring interface under long-term loads, reducing the risk of anchoring failure when re loaded. Taken together, the findings of the research indicate that PGR bolts can maintain higher prestress and strength in long-term support, and the theory model helps design the grouting parameters of PGR bolts. [ABSTRACT FROM AUTHOR]

Different motor learning methods (explicit or analogy learning) show different effects on motor performance stability, and reinvestment propensity plays an important role in motor performance stability. This study aimed to explore whether reinvestment propensity, that is, movement self-consciousness (MS-C) and conscious motor processing (CMP) as two dimensions, played a moderating role in the relationship between motor learning methods and motor performance stability. A total of 78 participants were randomly assigned to either the explicit or analogy learning group and their reinvestment propensity was measured. We recorded the number of golf putt goals in both the practice phase and the test phases (including a retention test and a stress test). In the moderating analysis, participants' reinvestment propensity was the moderating variable, and the dependent variable was motor performance stability (i.e., the difference between the two test phases). Results showed that motor performance was significantly different between practicing blocks, which indicated that the motor performance of learners was gradually increasing. The significant interaction between learning methods and the test phase on motor performance was detected, suggesting under stress, analogy learning was more likely to maintain the stability of motor performance, while explicit learning impaired the stability of motor performance. The CMP played a significant moderating role in the relationship between motor learning methods and motor performance stability. The result indicated that for learners with low CMP, the motor performance stability of analogy learning was better than explicit learning, while there was no significant difference in the stability of motor performance between the two learning methods for learners with high reinvestment propensity. No significant evidence was found that MS-C played a moderating role in the relationship between motor learning methods and motor performance stability. These findings expand the theoretical framework of motor skill learning and provide theoretical support for motor performance stability. • Analogy learning is more likely to maintain the stability of motor performance under stress. • CMP plays a significant moderating role in the relationship between motor learning methods and motor performance stability. • For people with low CMP, analogy learning is better than explicit learning in maintaining motor performance stability. • For people with high CMP, there is no significant difference in motor performance stability between the two learning methods. [ABSTRACT FROM AUTHOR]

• For the first time, neural networks were applied to denoise in spatial heterodyne spectroscopy, and significant results were achieved. • Four corresponding network models were constructed for denoising different brightness and noise levels. • The denoising ability of DnCNN in spatial heterodyne interferograms were comprehensively evaluated. • The reasonable selection of four neural network schemes were discussed. Spatial heterodyne spectroscopy is a hyperspectral remote sensing technology. With the continuous improvement of signal detection accuracy, new methods are urgently needed to further reduce the interference of noise on the information contained in spatial heterodyne interferograms. Convolutional neural networks, as an emerging field, have achieved good results in image denoising in recent years. This paper applies convolutional neural networks to the field of spatial heterodyne spectroscopy, constructs and trains four deep convolutional neural network models for denoising spatial heterodyne interferograms under different brightness and Gaussian noise conditions, and compares their performance with other algorithms. The results show that deep convolutional neural networks have significant advantages in denoising spatial heterodyne interferograms. Finally, a comparison of four neural networks was conducted to explore how to reasonably select network models. This work provides new ideas and effective solutions for reducing the interference of noise on spatial heterodyne spectral information and improving signal detection accuracy. [ABSTRACT FROM AUTHOR]

• Practical solar spectrum measured by an integrated optical chip. • Solar radiation is coupled to a fiber and transmits flexibly over 50 m to the lab. • The observed O 2 (687.7 nm, 761.9 nm) and H 2 O (718.4 nm) absorption lines are in good agreement with the literature. • This work proves feasibility of chip-based instrument for atmospheric observation, climatology, and exoplanet exploration. We demonstrate solar spectrum measurement in the visible-near-infrared region by integrated waveguide spectral lens (WSL). Light through the chip is dispersed and focused on a camera placed at the designed distance without any free-space lens. Commercial polymer materials with low propagation loss near visible region are chosen for wafer-scale fabrication. The solar radiation is coupled to a fiber via a home-made setup and the captured light is transmitted over ∼ 50 m to the lab, where the spectrum is examined by two WSL chips for broadband and fine analysis, respectively. The observed O 2 (687.7 nm, 761.9 nm) and H 2 O (718.4 nm) absorption lines are in good agreement with the results from a commercial optical spectral analyzer and the literature. This experiment proves the feasibility of using planar WSL chips as low-cost and versatile components for the development of compact and portable spectrometer equipment. [ABSTRACT FROM AUTHOR]

• Achieved arbitrary power ratio splitter with only 4 microheaters on a multimode waveguide. • Construct a nonlinear equivalent neural network to represent the thermally controlled multimode interference device. • Using "offline" inverse design to achieve splitting functions without tedious numerical simulations. A 3-port beam splitter with arbitrary power ratio is developed on a multimode waveguide by effectively manipulating the multimode interference through 4 locally placed microheaters. For matched interference, different light powers are coupled to the three output waveguides but the sum does not undergo extra loss, whereas the splitter integrates also the variable attenuation function, from zero to maximum, to any of the outputs. Different from the conventional design approach using extensive simulations, an equivalent neural network is established to represent such a multimode waveguide system based on experimental data only. From this neural network, an optimization program is developed to inverse the output and input. For a target power splitting ratio, the required heater currents can be readily calculated on a computer and then loaded onto the waveguide chip. The experimental results match well with the targets. This work demonstrates that the nonlinear activation is inherently integrated in the thermally controlled multimode waveguide though the optical material itself is linear. This feature can be used to construct complex deep learning networks. It may lead to the development of advanced integrated optical switches and computing networks. [ABSTRACT FROM AUTHOR]