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Hypophosphite (P(I)) is ubiquitous in some waste streams. It may contribute to the eutrophication of water bodies, yet conventional methods are ineffective in treating P(I)-laden wastewater. Here, we propose a novel CaO2/ultraviolet (UV) system that can simultaneously remove P(I) and recover Ca-phosphate. This system lies in the simultaneous release of OH-, Ca2+, and H2O2, with the last being activated and producing reactive oxygen species (ROS) under UV irradiation. Subsequently, the generated ROS converts P(I) to phosphite and phosphate, forming Ca-phosphate with the released Ca2+ at pH 11.0. Beyond activating H2O2, UV light also promotes the dissolution of CaO2 powders. The system removes 97.0% of 1.0 mM P(I) in 6 h with dosing 2.0 mM CaO2. The presence of 5.0 mM HCO3- drops P(I) removal from 97.0 to 14.1% by competing with P(V) toward Ca2+. Nitrate and humic acid show similar effects by adsorbing UV light or quenching ROS. However, we may overcome the adverse effects with an enhanced CaO2 dose. For example, with 10 mM CaO2, the CaO2/UV system removed more than 78% of non-ortho P from actual electroless rinse water. These results confirmed that CaO2/UV is an exciting all-in-one system for treating P(I)-laden wastewater and recovering valuable P products.

Curriculum ideological and political construction is a novel requirement and concept of the current curriculum colleges and universities’ teaching reform. As the undergraduate core course majoring in Polymer Materials and Engineering, the course of Polymer characterization and Testing has updated their teaching concept, and introduces ideological and political elements in their course to keep pace with the time. Firstly, it expounds the necessity of performing ideological and political education in the new engineering professional curriculum, and then introduces the implementation status of the curriculum ideological and political education. Secondly, the professional curriculum framework system and the teaching content were combined, and it deeply excavates the strategies and methods of the curriculum ideological and political education. Thus, the experience for the ideological and political construction of the professional curriculum under the background of the new engineering was provided.

In this article, a virtual-goal-guided rapidly exploring random tree (RRT)-based visual servoing approach is proposed for nonholonomic mobile robots to simultaneously satisfy the field-of-view (FOV) constraint and the velocity constraints during the motion toward the desired pose. The presented approach contains two parts: 1) trajectory planning in the scaled Euclidean space and 2) trajectory tracking control. For the trajectory planning part, a new virtual-goal-guided RRT algorithm is designed to guarantee the FOV constraint and the velocity constraints by iteratively exploring the scaled Euclidean space in the presence of unknown image depth. Specifically, a virtual goal directly behind the desired pose is set to guide the tree to extend laterally into the area wherein the robot is easier to satisfy the FOV constraint. In addition, the lateral extension of the tree also helps decrease the lateral error of the robot as much as possible. Following each successful extension toward the virtual goal node, a greedy extension from the newly explored node to the desired pose is attempted using a polar stabilization controller, so that the planned trajectory can accurately arrive at the desired pose. Each newly explored edge in the scaled space is projected into the image space to check for the FOV limit. For the visual tracking part, the final searched trajectory in the scaled space is first transformed into image feature trajectories, which are then tracked by an image-based visual tracking controller. Experiments validate the effectiveness of the proposed approach.

Phosphorus (P) is often regarded as the primary stimulant for eutrophication, while its importance as a crucial life element is also well acknowledged. Given its future scarcity, P recycling from waste streams is suggested and practiced. Electrochemically mediated precipitation (EMP) is a robust and chemical-free process for P removal and recovery, yet it requires further developments. The first generation of the CaCO3-packed electrochemical precipitation column successfully solved the problem of H+-OH− recombination, achieving enhanced P removal efficiency with less energy consumption but suffering from low Ca-phosphate purity in recovered products. Herein, a new concept of a basket-anode electrochemical system is proposed and validated to prevent direct H+-OH− recombination and enhance product purity. The CaCO3 pellets packed basket anode alleviates the OH− depletion by CaCO3-H+ interaction and provides extra Ca2+ for enhanced P removal. The novel structure of the basket anode, by its derived acidic anode region and alkaline cathode region, completely avoids the precipitation of Ca-phosphate on the packed CaCO3 and greatly facilitates the collection of high-quality Ca-phosphate product. Our results suggest that almost 100% of the removed P was in high-purity, highly crystalline Ca-phosphate on the cathode. The recovered products contained significantly more P (13.5 wt%) than in the previous study (0.1 wt%) at similar energy consumptions (29.8 kWh/kg P). The applied current density, pellets size, and influent P concentration were critical for P removal performance, product purity, and power consumption. We further demonstrated the long-term stability of this novel system and its technical and economic feasibility in treating real stored urine. Our study provides new cell architectural designs to enhance the performance of EMP systems and may inspire innovations and developments in other electrochemical water treatment processes.

Background: Elevated levels of inflammatory cytokines such as Interleukin (IL)-17A have been repeatedly linked with major depression in both animals and humans. Our recent double-blinded Randomized Placebo-controlled Trial (RCT) discovered significant efficacy of a traditional Chinese medicine substance, namely the Lycium barbarum polysaccharide (LBP), on reducing depressive symptoms among adolescents with subthreshold depression. Here, we further investigated whether the antidepressant property of LBP was associated with its anti-inflammatory effect on adolescents with subthreshold depression. Methods: In this 6-week RCT, we measured common cytokine levels from participants’ peripheral blood samples, both at baseline and at the end of the 6-week intervention with either LBP (intervention group, N=14) or placebo (control group, N=10). Independent t-tests were used to compare the change of cytokine levels between groups.Network-based analysis was applied to evaluate the systemic immune responses to the interventions. Results: The intervention and control groups were matched on demographic and clinical characteristics. As expected, the LBP group exhibited a greater reduction in IL-17A compared to the placebo group (t = -2.25, P = 0.04) after the 6-week interventions. Moreover, network-level analysis showed that LBP reduced the correlations and connectivity among cytokines (Z = 3.34, P < 0.01), which was in turn associated with improvement of depressive symptoms. Conclusions: Our findings demonstrated that 6-week repeated LBP administrations downregulated immune responses in adolescents with StD, which could be a key mechanistic pathway underpinning the antidepressant effect of LBP.

Magnetic coupling resonant wireless energy transmission technology has become an important research direction for electric vehicle wireless charging systems. This paper proposes an efficiency optimization strategy for the electric vehicle wireless energy transmission system based on LCL-S topology to improve the efficiency of electric vehicle magnetic coupling resonant wireless charging. This paper analyzes the optimization method of system efficiency based on LCL-S topology, establishes an experimental model in MATLAB/Simulink simulation software, and verifies it with the control variable method. The experiment shows that the efficiency optimization strategy based on the LCL-S topology proposed in this paper can effectively improve the system transmission efficiency and stabilize the transmission efficiency at a higher level faster.

Owing to advantages of large workspace and flexible movement, wheeled mobile robots are widely applied in industry. With vision module for environment perception, visual servoing of wheeled mobile robots has been one of the hottest research topics in robotic fields. Due to different demands for various applications and specific properties of the system, many challenges are faced for designing visual servoing control strategies. In this paper, development of visual servoing for mobile robots is elaborated in visual and control modules, respectively. The vision module along with various uncertainties are analyzed, which provides feedback signals for the servo controller, thus associating the image space with the motion space for further control. Moreover, motion controllers are devised under various constraints for different objectives, such as pose regulation and trajectory tracking. Research trends are discussed to show further focus of visual servoing of mobile robots.

Vehicular Edge Computing (VEC) is a new paradigm which improves the quality of service (QoS) of vehicular applications. However, in VEC networks, the computation resources of each VEC server are limited, and there are mismatches between the resources requested by vehicles and the resources that can be allocated by VEC servers, which increase the delays of completing computation tasks. To address the problem, in this paper, we jointly analyse the computation offloading and resource allocation based on the Walrasian equilibrium. Firstly, we analyze utilities of vehicles and VEC servers, and model the computation offloading and resource allocation as optimization problems considering delay constraints, respectively. Then, we convert the joint problem into a VEC networks welfare maximization problem. Based on the dual decomposition optimization method, we solve the problem and find the best strategies of vehicles and VEC servers, which means the state of Walrasian equilibrium. Moreover, we propose an algorithm with a fast convergence rate to find the solution of VEC Walrasian equilibrium. Simulation results demonstrate the effectiveness of the proposed analytical method and algorithm.

Word-of-Mouth (WoM) mode, as a new mode of task sensing in crowdsourcing, shows high efficiency in building contributor groups. To better tap the potential of WoM mobile crowdsourcing, the underlying rationale of interactions among contributors needs to be well understood. In this article, we analyze the behavior of contributors based on the Stackelberg game, and find optimal strategies for contributors. We consider two different crowdsourcing tasks announcement methods: 1) one-time parallel and 2) multitime sequential announcement ways, which form two different market scenarios. Then, we formulate two-stage and multistage contributor game models for the two scenarios, respectively. The backward induction approach is used to analyze each game, and the problems to find the optimal strategies for contributors are transformed into optimization problems. Furthermore, the Lagrange multiplier and Karush–Kuhn–Tucker (KKT) methods are used to solve the optimization problems. We theoretically prove that Stackelberg equilibrium exists and is unique. Based on the proposed theory, we design algorithms to compute the profit-maximizing contribution quantity of sensing data for each contributor. Finally, we present the detailed experimental analysis and the experimental result shows the effectiveness of the proposed algorithms.

Aerobic exercise is effective in alleviating mood symptoms while the mechanism is poorly understood. There are limited clinical trials that investigated the effect of exercise on the anterior cingulate cortex (ACC), a key brain region involved in mood regulations, in adolescents with subthreshold mood syndromes. This randomized controlled trial (RCT) of aerobic exercise was undertaken in a middle school in Guangzhou, China. Participants were adolescents aged 12–14 with subthreshold mood syndromes including depressive and manic symptoms and were randomly assigned to an aerobic exercise intervention or a psychoeducation control group. Participants in the exercise group received moderate-intensity exercise intervention, consisting of 30 mins running, 4 days per week for 3 months. The primary outcome in this study was structural changes in the ACC from baseline to post intervention. The trial was registered with ClinicalTrial.gov (NCT03300778). Of 56 participants who met the criteria for subthreshold mood syndromes, 39 (41.03% males) had complete MRI data, with 20 and 19 subjects in the exercise and control group, respectively. At baseline, demographic information (e.g., age and sex), clinical symptoms, and the gray matter volume and cortical thickness of ACC were matched between the two groups. After 12 weeks of treatment, participants in the exercise group displayed increased gray matter volume of the left rostral ACC (F1,30 = 5.73, p = 0.02) and increased cortical thickness of the right rostral ACC (F1,30 = 7.83, p = 0.01) when compared with the control group. No significant differences were found for caudal ACC cortical thickness and gray matter volume. Our data demonstrate that 12-week, moderate-intensity aerobic exercise can induce structural changes in the rostral ACC in adolescents with subthreshold mood syndromes.