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This article presents a comprehensive survey of the integration of machine learning techniques into robotic grasping, with a special emphasis on the challenges and advancements for space applications. The incorporation of artificial intelligence, particularly through deep learning, reinforcement learning, transfer learning, convolutional neural networks and recurrent neural networks, has significantly revolutionized robotic grasping. These advancements facilitate autonomous, efficient, and sophisticated manipulation in the challenging environment of outer space, transitioning from traditional mechanical grippers to sophisticated systems powered by advanced algorithms. This transition highlights the critical integration of sensory perception, grasp planning, and execution mechanisms, enhancing robots' capabilities to perceive, interact with, and manipulate objects with unprecedented precision and adaptability. The article meticulously outlines significant advancements achieved through the deployment of convolutional neural networks for visual information processing, RNNs for sequential decision-making, RL for autonomous strategy refinement, and transfer learning for leveraging pre-learned knowledge in novel tasks. These technologies address the unique challenges of space environments, such as varied textures, occlusions, microgravity conditions, and the sim-to-real gap, by enhancing sample efficiency, improving sim-to-real transfer capabilities, and integrating multimodal data for better object localization and pose estimation. Furthermore, the review explores the specific challenges faced in space robotic grasping, including handling varied textures and occlusions, adapting to unpredictable conditions, achieving real-time processing, and ensuring safety and reliability. It proposes future research directions focused on overcoming these hurdles, such as enhanced generalization through multimodal learning, robust sim-to-real transfer techniques, and the development of collaborative robotics and swarm intelligence. Critical to the development of ML models for robotic grasping are the roles of specialized datasets and simulation environments. Datasets like the Cornell Grasping Dataset and the Yale-CMU-Berkeley Object, along with simulation platforms such as Gazebo and PyBullet, provide essential resources for training, testing, and refining ML models. These tools enable researchers to simulate complex robotic systems and interactions within realistic environments, fostering rapid iterations on design and control strategies. In summary, this article offers in-depth insights into the progress, current challenges, and future prospects of machine learning techniques in robotic grasping for space exploration. It showcases significant strides made in the field and charts a path forward, emphasizing the need for innovative solutions to navigate the complexities of robotic manipulation in outer space. Through the strategic integration of advanced ML techniques, the development of adaptable and efficient robotic systems for space applications continues to advance, promising to unlock new possibilities in space exploration and beyond. • Surveys machine learning's application in space robotic grasping, noting key advances. • Highlights CNNs and RNNs' roles in robotic perception and action. • Discusses deep learning's evolution in autonomous space robotics. • Outlines future directions, emphasizing sim-to-real and multimodal learning. [ABSTRACT FROM AUTHOR]

For a continuous function f : R → R we define the corresponding graph by setting Γf ≔ {(x1, f(x1)) : x1 ∈ R }. We give the optimal Sobolev extension properties for the upper and lower domains corresponding to the graph Γ ψ c α for ψ c α (x1) = d(x1, C )α, where C is the classical ternary Cantor set in the unit interval and α ∈ (0, 1). [ABSTRACT FROM AUTHOR]

This paper investigates the dynamic behavior of a tethered satellite system in an elliptical orbit as the tethered subsatellite is deployed from a mother satellite at an out-of-plane angle while maintaining the tether at a constant in-plane pitch angle by a predefined control force acting on the subsatellite. A variable-length pendulum model is employed to describe the purely out-of-plane tether deployment dynamics, from which an analytical tether deployment control law is derived. The stability condition of the analytical control law is examined by Floquet theory. The corresponding analytical deployment law is asymptotically stable, and the requirement for a positive tension control input is guaranteed to ensure the controllability of the tether system. Following deployment, the critical conditions for the out-of-plane libration of the tethered subsatellite to become chaotic during the station-keeping phase are examined. Finally, simulation results reveal that the proposed approach can effectively and rapidly identify periodic, quasiperiodic, and chaotic motions using bifurcation diagrams, which provides valuable insights for enhancing the stability and reliability of such tethered satellite systems. • Proposed an analytical deployment law for a purely out-of-plane tethered satellite. • Revealed nonlinear phenomena of the system during the station-keeping phase. • Explored bifurcation characteristic and chaotic windows of the system. [ABSTRACT FROM AUTHOR]

• Derived new coupling-free analytical speed function (CASF) for in-plane libration-free transportation. • Proposed hierarchical sliding mode control for out-of-plane libration based on CASF. • Proved asymptotic stability of proposed control strategy by Lyapunov framework. This study presents an original analysis of out-of-plane libration dynamics and its control in partial space elevator cargo transportation. A comprehensive three-dimensional dynamic model of the partial space elevator has been derived to examine the effects of out-of-plane libration. To ensure a stable in-plane configuration, a coupling-free analytical speed function is developed that cancels out the coupling effects stemming from out-of-plane libration. A novel approach is developed to introduce a thrust control strategy for the elimination of out-of-plane libration using a virtual dynamic-based hierarchical sliding mode control law. By employing a new combined channel implementation mode, it is demonstrated that in and out-of-plane libration can be controlled with a single thruster, resulting in reduced fuel consumption. The stability of the proposed control strategy is proven within the Lyapunov framework. Numerical simulations validate the effectiveness of the control strategy and highlight its significance. Results show that out-of-plane libration increases the magnitude of in-plane libration, while climber movement amplifies out-of-plane libration. The control strategy successfully eliminates out-of-plane libration using limited control input, ensuring stable cargo transportation in the partial space elevator. [ABSTRACT FROM AUTHOR]

This study proposes a new control strategy for mitigating the libration in a partial space elevator (PSE). First, a libration-free or coupling-free analytical speed function is derived by assuming no in-plane and out-of-plane libration in the cargo transportation phase. Subsequently, a thrust is applied at the PSE's end body to counter any libration during this phase. A new set of geometric measures - bending and departure angles - are introduced to characterize the libration motion in PSE's dynamic equation. Based on these measures, two separate proportional-derivative (PD) stabilizing feedback laws are proposed. These PD laws individually control the bending and departure angles by thrust at the end body to suppress the libration that deviates from the libration-free trajectory. Due to the dynamic coupling between the bending and departure modes, they dominate alternatively. Accordingly, a novel fuzzy logic control law is proposed to switch between two PD controls based on the state of these two angles. Finally, a thrust vectoring control is proposed to combine in-plane and out-of-plane thrusting into a single actuation control. The asymptotic stability of the proposed control scheme is proved by Lyapunov's stability theory. Comprehensive numerical analyses demonstrate the effectiveness of the new geometric representation of the libration and the proposed new control strategy, highlighting their ability to suppress libration with bounded control inputs efficiently. • Derived new coupling-free analytical speed function for libration-free cargo transfer trajectory. • Introduced a new set of geometric measures, bending and departure angles, to describe libration motion. • Proposed a Fuzzy logic law to switch control between bending and departure angles. • Proposed a thrust vectoring control to combine in-plane and out-of-plane thrusting into one actuation. [ABSTRACT FROM AUTHOR]

Key message: OsMKK1, a MAPK gene, positively regulates rice Xa21-mediated resistance response and also plays roles in normal growth and development process of rice. The mitogen-activated protein kinase (MAPK) cascade was highly conserved among eukaryotes, which played crucial roles in plant responses to pathogen infection. Bacterial blight is the most devastating bacterial disease. Xa21 confers broad-spectrum resistance to Xanthomonas oryzae pv. Oryzae (Xoo). This study identified that the transcription level of OsMKK1 was up-regulated in resistant response against Xoo, thus overexpression (OsMKK1-OX) and RNA interference (OsMKK1-RNAi) transgenic rice lines under the background of Xa21 was constructed. Compared with recipient control plants 4021, the OsMKK1-OX lines significantly enhanced disease resistance to Xoo, on the contrary, the resistance of OsMKK1-RNAi lines was weakened, demonstrated that OsMKK1 played a positive role in Xa21-mediated disease resistance pathway. A number of pathogenesis-related proteins, including PR1A, PR2 and PR10A showed enhanced expression in OsMKK1-OX lines, supported that these PR genes may be regulated by OsMKK1 to participate in the defense responses. In addition, the agronomic traits of OsMKK1 transgenic plants were affected. Overall, these results revealed the role of OsMKK1 in Xa21-mediated resistance against Xoo and in the normal growth and development process in rice. [ABSTRACT FROM AUTHOR]

The experiment aimed to assess the effects of sucrose-chelated trace elements as substitutes for inorganic trace elements on the growth performance, carcass traits, meat quality, and muscle trace element deposition in growingfinishing pigs. Eighty-four castrated boars (70±3) kg were randomly divided into two treatment groups, each treatment with six replicates, and each replicate consisting of seven pigs. The control group (IE group) was fed a diet supplemented with 1% inorganic trace elements, and the experimental group (SE group) was fed a diet supplemented with 1% sucrosechelated trace elements. The experiment lasted for 56 days. The results showed that compared to IE group, the average daily gain, final weight, carcass weight, and backfat thickness of growing-finishing pigs in SE group increased ( P<0.05), the drip loss and refrigeration loss of the longissimus dorsi muscle decreased ( P<0.05), and the thawing loss showed a trend of reduction ( P>0.05). The redness (a*) value of the longissimus dorsi muscle of SE group increased after 45 minutes and one day of storage ( P<0.05). The T-AOC, T-SOD, and GSH-Px activities of the longissimus dorsi muscle of SE group were enhanced ( P<0.05), and the MDA content decreased ( P<0.05). Compared to IE group, the Cu and Se content in the longissimus dorsi muscle in SE group increased ( P<0.05), and the Fe and Mn content in the hind leg muscle increased ( P<0.05).The study indicates that using sucrose-chelated trace elements in the diet as substitutes for inorganic trace elements can improve the growth performance, carcass traits, meat quality, and muscle antioxidant status of growing-finishing pigs, and promote the deposition of trace elements in muscles. [ABSTRACT FROM AUTHOR]

Matching and pickup processes are core features of ride-sourcing services. Previous studies have adopted abundant analytical models to depict the two processes and obtain operational insights; while the goodness of fit between models and data was dismissed. To simultaneously consider the fitness between models and data and analytically tractable formations, we propose a data-driven approach based on the additive Gaussian Process Model (AGPM) for ride-sourcing market modelling. The framework is tested based on real-world data collected in Hangzhou, China. We fit analytical models, machine learning models, and AGPMs, in which the number of matches or pickups are used as outputs and spatial, temporal, demand, and supply covariates are utilized as inputs. The results demonstrate the advantages of AGPMs in recovering the two processes in terms of estimation accuracy. Furthermore, we illustrate the modelling power of AGPM by utilizing the trained model to design and estimate idle vehicle relocation strategies. [ABSTRACT FROM AUTHOR]

Background: Accumulating evidence suggests that anoikis resistance is a key process in cancer cell metastasis, making it an attractive therapeutic target. Therefore, anoikis may become a new treatment for gastric cancer. Methods: We used the univariate Cox regression method to screen gastric cancer-related anoikis genes, and a prognostic risk model was established. We analyzed differences between high- and low-risk groups in terms of tumor infiltrating immune cells, gene mutation signatures, and treatment of gastric cancer. Analysis of model associated genes at single-cell resolution was performed. Results: We filtered to 12 anoikis-related genes and built a prognostic risk model using seven of them, which performed well in multiple datasets. Patients with CCDC178 mutations had a worse prognosis. We also found that patients at low risk were more likely to benefit from chemotherapy and immunotherapy. ERBB2 was found to be highly expressed in epithelial cells and fibroblasts. Our analysis also indicated that gastric cancer samples with high infiltration of iCAFs had a worse prognosis. Conclusion: Seven anoikis-related genes were selected to establish a risk model. The model can be used to predict the prognosis of patients and guide the drug treatment, which provides a new idea for the evaluation and treatment of gastric cancer patients. [ABSTRACT FROM AUTHOR]

To meet the growing demand for the surveillance of resident space objects, the Shanghai Astronomical Observatory has developed a new observation method for monitoring resident space objects using a high frame rate astronomical CMOS camera, called the short-exposure stacking mode. This method can be used to observe objects of various orbit types with high observation accuracy. This paper describes the implementation of this new method of RSO observation, and the observation experiment of one MEO satellite and two GEO satellites using this method with a 40 cm telescope, the observation system has a 0.5 ° × 0.5 ° field of view. The observation results show that the accuracy of the sensor calibration is 0.3 - 0.4 arc-second. Compared with the external precision ephemeris, the standard deviation of the residual differences is better than 0.5 arc-second, which means that the precise orbit of space objects can be obtained with enough observation. And compared with the method that uses drift scan CCD, the observation time efficiency of the short-exposure stacking mode is better. [ABSTRACT FROM AUTHOR]

Background: Colon cancer is one of the most prevalent cancers of the digestive tract. There is mounting evidence that genes associated with oxidative stress might affect the tumour immune microenvironment during tumour growth, maintenance, and treatment response. However, how oxidative stress-related genes affect prognostic importance, tumour microenvironment features, and treatment outcomes in colon cancer patients has not been fully elucidated. Methods: The Cancer Genome Atlas (TCGA) dataset was used to construct a signature model and nomogram using step and Cox regression approaches to investigate how gene expression affected immunological responses to colon cancer, including the degree of immune infiltration, MSI, and drug sensitivity. Results and conclusions: The nomogram and the signature model had strong prognostic potential for colon cancer, with gene expression highly correlated with multiple immune cells. The first signature model and nomogram including oxidative stress-related genes were constructed for use in clinical decision-making. In addition, SRD5A1, GSR, TXN, TRAF2 and TRAP1 were identified as potential biomarkers for colon cancer diagnosis and indicators for immunotherapy. [ABSTRACT FROM AUTHOR]

To develop symptom networks and examine the longitudinal relationships of depressive symptoms among middle-aged and older adults in China. This study used three-wave data from the China Health and Retirement Longitudinal Study (2013 (T1), 2015 (T2), and 2018 (T3)). Depressive symptoms were measured by the 10-item Center for Epidemiologic Studies Depression Scale (CES-D). A multilevel vector autoregression model (VAR) was used to identify ten depressive symptoms dynamically interacting with each other over time. A total of 3,558 participants were included in the final analysis. The strongest direct effects were 'D10: felt fearful' -> 'D6: felt everything I did was an effort' (β = 0.14). 'D10: felt fearful' reported the largest value of out-predictability (r = 0.064) and out-strength (r = 0.635). 'D3: felt depressed' reported the largest value of in-predictability (r = 0.077) and in-strength (r = 0.545). Substantial heterogeneity in the network may stem from an individual's sex and place of residence. 'Felt fearful' was the strongest predictor compared to the other nine depressive symptoms based on node centrality. Our study suggests that, after understanding the causes of fear, strategies to reduce fear should be incorporated into multimodal interventions for middle-aged and older adults with depressive symptoms. [ABSTRACT FROM AUTHOR]

This study investigated to what extent socioeconomic status (SES) disparity associates with cognitive and physical impairment within older Asian Americans in comparison with other races/ethnicities. Data were from the National Health and Nutrition Examination Survey 2011–2018 that included 3,297 White, 1,755 Black, 1,708 Hispanic, and 730 Asian Americans aged ≥ 60. Physical functioning was measured by activities of daily living (ADL) or instrumental activities of daily living (IADL). Memory and language fluency were evaluated using the Alzheimer's Disease Word List Memory Task and Animal Fluency Tests, respectively. Multivariate logistic regressions were conducted to investigate the association between SES and physical and cognitive impairment within racial/ethnic groups, and seemingly unrelated regressions compared coefficients across subgroups. Asians with ≤ high school education had the highest prevalence of age- and sex-adjusted memory impairment among all races/ethnicities, while no difference was observed for those with > high school education. ADL/IADL disability odds did not differ between Asians and Whites, but Asians were more likely to exhibit impaired verbal fluency. Education disparity for ADL disability (OR, 3.40; 95% CI, 2.20–5.25) and memory impairment (OR, 11.57; 95% CI, 6.59–20.31) were largest among Asians compared to Whites, Blacks, and Hispanics. Income disparity for function impairment showed no significant difference across racial/ethnic groups (all P > 0.05). Asians experienced the highest burden of physical functioning and memory impairment due to education disparity. Efforts should focus on strengthening research infrastructure and creating targeted programs and services to improve cognitive and physical health for racially/ethnically underrepresented older adults with lower education attainment. [ABSTRACT FROM AUTHOR]

This paper develops a dual-phase control strategy based on the piecewise cooperative game method to balance the multiple competing objectives for cargo transportation by a partial space elevator in terms of orbital state stability and cargo transport efficiency and ensure final state stability. The cargo transportation is performed in the libration-free mode to facilitate the control implementation, where all libration motions are kept at zero. The new control strategy is split into phases I and II. Phase I focuses on cargo transportation and covers most cargo transfer distances. Multiple competing control objectives in this phase are balanced by the newly proposed piecewise cooperative game method. Once the remaining distance meets the preset threshold, the transportation enters phase II, which focuses on bringing the state of the partial space elevator to a stable equilibrium state. A shrinking horizon model predictive control method is used to ensure the state converges to the equilibrium point by the end of transportation. The simulation results reveal that the newly proposed dual-phase control scheme effectively balances multiple competing control objectives in the cargo transfer period. Moreover, by introducing phase II, the system can achieve a stable equilibrium state by the end of the transfer period. [ABSTRACT FROM AUTHOR]

Summary: During pregnancy many women may experience negative emotions and sleep disturbances. This systematic review and meta‐analysis was conducted to assess the efficacy of cognitive behavioural therapy for insomnia (CBT‐I) or sleep disturbance in pregnant women. From the earliest available publications to 15 April 2022, seven electronic literature databases were searched: PubMed, Web of Science, Cochrane Library, Embase, Chinese National Knowledge Infrastructure, Wanfang Data, and VIP Database for Chinese Science and Technology Journal. Randomised controlled trials of CBT‐I in pregnant women with insomnia or sleep disorders were included. The methodological bias of the included studies was assessed using the Cochrane risk of bias tool. The meta‐analysis was performed using RevMan 5.4 software. Stata Statistical Software: Release 15 was used for sensitivity analysis and publication bias. We included eight randomised controlled trials involving 743 pregnant women. Meta‐analysis showed that, compared with the control group, CBT‐I significantly improved the Insomnia Severity Index (mean difference [MD] = −4.25, 95% confidence interval [CI, −6.32, −2.19], p < 0.001), The Pittsburgh Sleep Quality Index (MD = −3.30, 95% CI [−4.81, −1.79], p < 0.001), sleep onset latency (standardised mean difference [SMD] = −1.25, 95% CI [−2.01, −0.50], p = 0.001), anxiety (SMD = −0.99, 95% CI [−1.32, −0.67], p < 0.001), and depression (SMD = −0.40, 95% CI [−0.72, −0.07], p = 0.02). No significant differences were found in total sleep time (SMD = 0.31, 95% CI [−0.54, 1.17], p = 0.47) and sleep efficiency (SMD = 0.80, 95% CI [−0.53, 2.13], p = 0.24). CBT‐I significantly improved pregnant women's sleep quality, insomnia severity, depression, and anxiety. This meta‐analysis provides evidence that CBT‐I is valid for insomnia or sleep disturbances during pregnancy. [ABSTRACT FROM AUTHOR]

Nodal shape functions and their gradients are vital in transferring physical information within the material point method (MPM). Their continuity is related to numerical stability and accuracy, and their support domain size affects computational efficiency. In this paper, a scheme of aggregated and smoothed Bernstein functions is proposed to improve the MPM. In detail, the Bernstein polynomials are smoothed with a convolution reformation to eliminate the cell crossing error, and an aggregation strategy is implemented to cut down the node amount required for field probing. Hierarchical MPM variants are obtained with choices of original Bernstein polynomials and degrees of smoothing. Numerical examples show that mass, momentum, and energy conservations are all well met, and no cell crossing noise exists. In addition, solution accuracy and numerical stability are significantly improved in large deformation problems. [ABSTRACT FROM AUTHOR]

Maintaining accurate topology of the low-voltage distribution grid (LVDG) are critical to the operations and maintenance of power distribution systems. However, this goal is hard to achieve due to the fast-changing LVDG topology. To this end, we focus on the abnormal customer-transformer relationships identification in the LVDG and propose an identification method based on an Adaptive Dual-channel Graph Wavelet Neural Network (ADGWN) consisting of two identical GWNs connected with the attention mechanism. In the proposed ADGWN, two GWNs learn customer embedding simultaneously from the LVDG topology graph and the feature graph that is constructed from customer electricity consumption data with the k-Nearest Neighbor algorithm. The topology identification results of these two GNNs are then adaptively fused to form the ultimate identification result with the attention mechanism by dynamically balancing the aforementioned two types of information. To validate the performance of our proposed method, we further build a real benchmarking dataset from customer electricity consumption data collected from a certain substation in Shanghai, China. Experimental results show that the proposed ADGWN achieves 100.0% LVDG topology identification accuracy and significantly outperforms the state-of-the-art. Our proposed method can help operators of power distribution systems maintain the accurate topology in a timely and economic manner. [ABSTRACT FROM AUTHOR]

Robotic on-orbit servicing presents the opportunity for repairing and refueling satellites and deorbiting space objects. Performing such tasks is challenging because they must be done autonomously and accurately with high robustness. Ground testing, such as air-bearing-based spacecraft simulators, is widely used to develop and validate the design and control techniques of space robotics required by modern spacecraft applications. This paper presents the development of planar air-bearing microgravity simulators with a 3-DOF robotic manipulator for autonomous spacecraft tracking, rendezvous, and capture control of a free-floating target. The system includes a pseudo-galactic star tracking system for pose determination and navigation of spacecraft simulators. A second optical tracking module was also developed to determine the pose of a target spacecraft relative to the chaser spacecraft. Path planning and PD trajectory tracking algorithms were developed for spacecraft tracking and rendezvous. The experiments successfully demonstrated that the testbed could be used to study autonomous spacecraft rendezvous and capture a tumbling spacecraft by a robotic manipulator in a space-like testing environment. • Developed air-bearing spacecraft simulators for spacecraft rendezvous control. • Developed air-bearing lifted robotic manipulator for capturing a spinning target. • Tested autonomous path planning and autonomous robotic capture by the system. [ABSTRACT FROM AUTHOR]

Aims/Introduction: To compare the application value of different machine learning (ML) algorithms for diabetes risk prediction. Materials and Methods: This is a 3‐year retrospective cohort study with a total of 3,687 participants being included in the data analysis. Modeling variable screening and predictive model building were carried out using logistic regression (LR) analysis and 10‐fold cross‐validation, respectively. In total, six different ML algorithms, including random forests, light gradient boosting machine, extreme gradient boosting, adaptive boosting (AdaBoost), multi‐layer perceptrons and gaussian naive bayes were used for model construction. Model performance was mainly evaluated by the area under the receiver operating characteristic curve. The best performing ML model was selected for comparison with the traditional LR model and visualized using Shapley additive explanations. Results: A total of eight risk factors most associated with the development of diabetes were identified by univariate and multivariate LR analysis, and they were visualized in the form of a nomogram. Among the six different ML models, the random forests model had the best predictive performance. After 10‐fold cross‐validation, its optimal model has an area under the receiver operating characteristic value of 0.855 (95% confidence interval [CI] 0.823–0.886) in the training set and 0.835 (95% CI 0.779–0.892) in the test set. In the traditional LR model, its area under the receiver operating characteristic value is 0.840 (95% CI 0.814–0.866) in the training set and 0.834 (95% CI 0.785–0.884) in the test set. Conclusions: In the real‐world epidemiological research, the combination of traditional variable screening and ML algorithm to construct a diabetes risk prediction model has satisfactory clinical application value. [ABSTRACT FROM AUTHOR]

Turbine blades, mainly formed by investment casting, are one of the core components of an aero-engine. However, the profile accuracy of turbine blades shaped by investment casting sometimes cannot directly meet the design requirements, and there will be some local areas exceeding the given form tolerance. In order to reduce the blade rejection rate and develop an advanced CNC correcting method, a new process model construction method for CNC correction of turbine blades is proposed. In this method, a new multi-constraint optimization model for the design sectional curve position of turbine blades is developed, which not only enables the process model constructed from the optimized sectional curves to best fit the actual blade geometry but also minimizes the local error areas to be corrected on the actual geometry. Two typical turbine blades have been successfully performed to demonstrate the effectiveness of the proposed method. The results show that the proposed method can significantly reduce the local error areas compared to the existing method while not exceeding the given multiple constraints. Therefore, the constructed process model can be used to generate CNC tool paths to correct the minimum local error areas and thus convert the scrap turbine blades into qualified ones. [ABSTRACT FROM AUTHOR]

Four A2B cobalt corrole complexes 1–4 appending two methoxy or hydroxyl groups on the 10‐meso phenyl group had been synthesized. Four cobalt corroles showed high electrocatalytic activity for hydrogen evolution reaction (HER) in the organic phase and in the aqueous phase. The hydrogen evolution pathway was EECEC when using acetic acid as proton source. When trifluoroacetic acid was used as proton source, the hydrogen evolution route via EECEC or EECC depending on the concentration of trifluoroacetic acid. Cobalt corrole 4 showed the best HER performance with the kobs of 122.68 s−1 in organic phase and the TOF of 832.2 h−1 in aqueous phase respectively. The results suggested the phenyl hydroxyl group at the cobalt corrole peripheral may act as the proton relay group in HER and the o‐hydroxyl of phenyl was better than m‐ hydroxyl for proton relay. [ABSTRACT FROM AUTHOR]

Background: Symptom networks can provide empirical evidence for the development of personalized and precise symptom management strategies. However, few studies have explored the symptom networks of multidimensional symptom experiences in cancer survivors. The objectives of this study were to generate symptom networks of multidimensional symptom experiences in cancer survivors and explore the centrality indices and density in these symptom networks Methods: Data from 1065 cancer survivors were obtained from the Shanghai CANcer Survivor (SCANS) Report. The MD Anderson Symptom Inventory was used to assess the prevalence and severity of 13 cancer‐related symptoms. We constructed contemporaneous networks with all 13 symptoms after controlling for covariates. Results: Distress (rs = 9.18, rc = 0.06), sadness (rs = 9.05, rc = 0.06), and lack of appetite (rs = 9.04, rc = 0.06) had the largest values for strength and closeness. The density of the "less than 5 years" network was significantly different from that of the "5–10 years" and "over 10 years" networks (p < 0.001). We found that while fatigue was the most severe symptom in cancer survivorship, the centrality of fatigue was lower than that of the majority of other symptoms. Conclusion: Our study demonstrates the need for the assessment of centrality indices and network density as an essential component of cancer care, especially for survivors with <5 years of survivorship. Future studies are warranted to develop dynamic symptom networks and trajectories of centrality indices in longitudinal data to explore causality among symptoms and markers of interventions. [ABSTRACT FROM AUTHOR]

The Zinc-air battery (ZAB) has become a hot research topic for nearly a decade due to its high energy densities. As an important category of catalysts for ZAB, perovskites have attracted extensive interests because of their environmentally friendly properties, cheapness, and excellent electrocatalytic performances. This review article discusses the mechanistic analyses regarding the progress of perovskites for ZAB. In addition, electrode manipulation methods of perovskites for battery device are also emphasized. Finally, perspectives are given on the limitations of the current perovskite catalysts for ZABs. We hope that this review will provide new clues for promoting perovskites as catalysts for many energy-storage and conversion applications in the future. [ABSTRACT FROM AUTHOR]

Background: Liver cancer is the fifth leading cause of cancer death worldwide, but early diagnosis and treatment of liver cancer remains a clinical challenge. How to screen and diagnose liver cancer early and prolong the survival rate is still the focus of researchers.Methods: Cell experiments were used to detect the effect of WZ35 on the colony formation ability and proliferation activity of hepatoma cells, nude mouse experiment to observe the in vivo anticancer activity and toxic side effects of WZ35; metabolomics analysis, glucose metabolism experiment and Seahorse analysis of liver cancer cells treated with WZ35; cell experiments combined with bioinformatics analysis to explore the mechanism of WZ35-mediated metabolic reprogramming to exert anticancer activity; tissue microarray and case analysis to evaluate the clinical significance of biomarkers for early diagnosis, treatment and prognosis evaluation of liver cancer.Results: WZ35 inhibited the proliferation activity of various cell lines of liver cancer, and showed good therapeutic effect in nude mice model of hepatocellular carcinoma without obvious toxic and side effects; WZ35 inhibited the absorption of glucose in hepatoma cells, and the drug effect glycolysis, phosphorylation and purine metabolism are relatively seriously damaged; WZ35 mainly inhibits YAP from entering the nucleus as a transcription factor activator by activating oxidative stress in liver cancer cells, reducing the transcription of GLUT1, and finally reducing its GLUT1. Tissue microarray and case analysis showed that GLUT1 and YAP were highly expressed and correlated in liver cancer patients, and were associated with poor patient prognosis. The GLUT1-YAP risk model had a high score in predicting prognosis.Conclusion: The study confirms that WZ35 is a small molecule glycolysis inhibitor, and through its properties, it mediates metabolic reprogramming dominated by impaired glycolysis, oxidative phosphorylation and purine metabolism to inhibit the proliferation activity of liver cancer cells. Our findings present novel insights into the pathology of liver cancer and potential targets for new therapeutic strategies. GLUT1-YAP has important reference significance for predicting the stages of disease progression in liver cancer patients and have the potential to serve as novel biomarkers for the diagnosis and treatment of liver cancer. [ABSTRACT FROM AUTHOR]

Van der Waals heterostructures show potential in electronic and optoelectronic devices. However, most heterostructures were formed based on the combination of two kinds two-dimensional (2D) materials. It is interesting to investigate the heterostructures of three kinds of 2D materials with unique band structure for photodetection and tunneling. In this work, vertical stacked WSe2/black phosphorus (BP)/MoS2 heterostructure has been made. By tuning the middle layer BP thickness from thin to thick, the device can be regarded as tunneling transistor and photodetector. Throughout thin BP (9 nm) sandwiched, tunneling transistor is realized in WSe2/BP/MoS2 heterojunction with a high ∼μA level tunneling current. Temperature dependent electrical characteristics proved tunneling mechanism. Throughout thicker BP (20–30 nm) flake sandwiched, high-performance photodetector can be achieved. The large bandgap of WSe2 and MoS2 can further reduce the dark current to ∼10 pA level at 3.0 V drain–source bias. Moreover, the unique band alignment facilitates the photo-electrons flow and blocked photo-holes in the BP channel. The photoresponsivity can reach 1.43 A/W at near infrared light with λ = 1342 nm. Our work suggests an effective scheme to design high performance electronic and optoelectronic devices assembled by 2D materials. [ABSTRACT FROM AUTHOR]

The identification of subgroups of people living with HIV in China based on the severity of symptom clusters and individual symptoms is crucial to determine group-specific symptom management strategies. Participants reported 27 highly prevalent HIV/AIDS-related symptoms. Latent profile analysis based on symptom severity was used to identify person-centered subtypes of HIV/AIDS-related symptoms. Symptom networks were compared among subgroups identified by latent profile analysis. A total of 2927 eligible people living with HIV (PWH) were included in the analysis. Five profiles were identified: "Profile 1: all low symptom severity" (n2 = 2094, 71.54%), "Profile 2: medium symptom severity with syndemic conditions" (n3 = 109, 3.72%), "Profile 3: medium symptom severity with low functional status" (n1 = 165, 5.64%), "Profile 4: medium symptom severity in transitional period" (n4 = 448, 15.31%), and "Profile 5: all high symptom severity" (n5 = 111, 3.79%). Except for Profile 1 and Profile 5, the symptom severity was similar among the other three profiles. Profiles 1 (2.09 ± 0.52) and 4 (2.44 ± 0.66) had the smallest ∑s values, and Profiles 2 (4.38 ± 1.40) and 5 (4.39 ± 1.22) had the largest ∑s values. Our study demonstrates the need for health care professionals to provide PWH with group-specific symptom management interventions based on five profiles to improve their physical and psychological well-being. Future studies should be conducted in different contexts using different symptom checklists to further validate our results. [ABSTRACT FROM AUTHOR]

Rice bacterial blight, caused by Xanthomonas oryzae pv. oryzae (Xoo), is one of the most serious diseases affecting rice production worldwide. Xa21 was the first disease resistance gene cloned in rice, which encodes a receptor kinase and confers broad resistance against Xoo stains. Dozens of components in the Xa21-mediated pathway have been identified in the past decades, however, the involvement of mitogen-activated protein kinase (MAPK) genes in the pathway has not been well described. To identify MAPK involved in Xa21-mediated resistance, the level of MAPK proteins was profiled using Western blot analysis. The abundance of OsMPK17 (MPK17) was found decreased during the rice-Xoo interaction in the background of Xa21. To investigate the function of MPK17, MPK17-RNAi and over-expression (OX) transgenic lines were generated. The RNAi lines showed an enhanced resistance, while OX lines had impaired resistance against Xoo, indicating that MPK17 plays negative role in Xa21-mediated resistance. Furthermore, the abundance of transcription factor WRKY62 and pathogenesis-related proteins PR1A were changed in the MPK17 transgenic lines when inoculated with Xoo. We also observed that the MPK17-RNAi and -OX rice plants showed altered agronomic traits, indicating that MPK17 also plays roles in the growth and development. On the basis of the current study and published results, we propose a "Xa21-MPK17-WRKY62-PR1A" signaling that functions in the Xa21-mediated disease resistance pathway. The identification of MPK17 advances our understanding of the mechanism underlying Xa21-mediated immunity, specifically in the mid- and late-stages. [ABSTRACT FROM AUTHOR]

In this methodology, a nanomagnetic copper catalyst prepared via the immobilization of CuCl2 on the surface of Fe3O4@SiO2-APA-Amide/Imid ligand and its structure identified by several spectroscopic techniques including XRD, FT-IR, VSM, SEM, TEM, ICP-OES, TGA, EDX and elemental mapping analysis. This Fe3O4@SiO2-APA-Amide/Imid-CuCl2 nanomaterial can catalyze the preparation of 1,2,3-triazole derivatives through reactions of alkyne derivatives with NaN3 and aryl halides under ecofriendly conditions. It is noteworthy that the 1,2,3-triazole products were obtained with high yields when 2-phenylthiirane was used instead of aryl halides. In this research, one-pot three-component reactions were successfully performed in water, and the corresponding triazole products were obtained with high to excellent yields. After the end of the reaction, the Fe3O4@SiO2-APA-Amide/Imid-CuCl2 catalyst was recovered by magnetic separation and reused for 8 runs with a constant efficiency.Graphical abstract: In this methodology, a nanomagnetic copper catalyst prepared via the immobilization of CuCl2 on the surface of Fe3O4@SiO2-APA-Amide/Imid ligand and its structure identified by several spectroscopic techniques including XRD, FT-IR, VSM, SEM, TEM, ICP-OES, TGA, EDX and elemental mapping analysis. This Fe3O4@SiO2-APA-Amide/Imid-CuCl2 nanomaterial can catalyze the preparation of 1,2,3-triazole derivatives through reactions of alkyne derivatives with NaN3 and aryl halides under ecofriendly conditions. It is noteworthy that the 1,2,3-triazole products were obtained with high yields when 2-phenylthiirane was used instead of aryl halides. In this research, one-pot three-component reactions were successfully performed in water, and the corresponding triazole products were obtained with high to excellent yields. After the end of the reaction, the Fe3O4@SiO2-APA-Amide/Imid-CuCl2 catalyst was recovered by magnetic separation and reused for 8 runs with a constant efficiency. [ABSTRACT FROM AUTHOR]

The present paper aims to shed light on the influence of N6-methyladenosine (m6A) long non-coding RNAs (lncRNAs) and immune cell infiltration on colorectal cancer (CRC). We downloaded workflow-type data and xml-format clinical data on CRC from The Cancer Genome Atlas project. The relationship between lncRNA and m6A was identified by using Perl and R software. Kyoto Encyclopedia of Genes and Genomes enrichment analysis was performed. Lasso regression was utilized to construct a prognostic model. Survival analysis was used to explore the relationship between clusters of m6A lncRNAs and clinical survival data. Differential analysis of the tumor microenvironment and an immune correlation analysis were used to determine immune cell infiltration levels in different clusters and their correlation with clinical prognosis. The expression of lncRNA was tightly associated with m6A. The univariate Cox regression analysis showed that lncRNA was a risk factor for the prognosis. Differential expression analysis demonstrated that m6A lncRNAs were partially highly expressed in tumor tissue. m6A lncRNA-related prognostic model could predict the prognosis of CRC independently. "ECM_RECEPTOR_INTERACTION" was the most significantly enriched gene set. PARP8 was overexpressed in tumor tissue and high-risk cluster. CD4 memory T cells, activated resting NK cells, and memory B cells were highly clustered in the high-risk cluster. All of the scores were higher in the low-risk group. m6A lncRNA is closely related to the occurrence and progression of CRC. The corresponding prognostic model can be utilized to evaluate the prognosis of CRC. m6A lncRNA and related immune cell infiltration in the tumor microenvironment can provide novel therapeutic targets for further research. [ABSTRACT FROM AUTHOR]

This study aims to explore and visualize relationships among multiple psychological symptoms among people living with HIV (PLWH) with different HIV-positive durations and to compare centrality indices and densities of psychological symptom networks. We used subsets of data collected from five designated HIV/AIDS hospitals in China. Networks were constructed among 16 psychological symptoms. Centrality properties, including strength and closeness, were adopted to describe relationships among symptoms. The results showed that PLWH with longer HIV-positive durations had denser emotional networks, which indicated that they had more emotional neuroticism than their newly diagnosed counterparts. Sadness, self-abasement, and self-loathing were the most central psychological symptoms across different HIV-positive durations. Our study suggests the need to provide psychosocial support services targeting PLWH according to changing symptom severity and neuroticism trajectories. Interventions should focus on increasing empathy for PLWH and enhancing the ability to consider the situation from different perspectives to avoid the development of neuroticism in long-term survivors. [ABSTRACT FROM AUTHOR]

Background: Increasing evidence suggests that social factors and problems with physical and cognitive function may contribute to patients' rehospitalization risk. Understanding a patient's readmission risk may help healthcare providers develop tailored treatment and post-discharge care plans to reduce readmission and mortality. This study aimed to evaluate whether including patient-reported data on social factors; cognitive status; and physical function improves on a predictive model based on electronic health record (EHR) data alone.Methods: We conducted a prospective study of 1,547 hospitalized adult patients in 3 Kaiser Permanente Northern California hospitals. The main outcomes were non-elective rehospitalization or death within 30 days post-discharge. Exposures included patient-reported social factors and cognitive and physical function (obtained in a pre-discharge interview) and EHR-derived data for comorbidity burden, acute physiology, care directives, prior utilization, and hospital length of stay. We performed bivariate comparisons using Chi-square, t-tests, and Wilcoxon rank-sum tests and assessed correlations between continuous variables using Spearman's rho statistic. For all models, the results reported were obtained after fivefold cross validation.Results: The 1,547 adult patients interviewed were younger (age, p = 0.03) and sicker (COPS2, p < 0.0001) than the rest of the hospitalized population. Of the 6 patient-reported social factors measured, 3 (not living with a spouse/partner, transportation difficulties, health or disability-related limitations in daily activities) were significantly associated (p < 0.05) with the main outcomes, while 3 (living situation concerns, problems with food availability, financial problems) were not. Patient-reported cognitive (p = 0.027) and physical function (p = 0.01) were significantly lower in patients with the main outcomes. None of the patient-reported variables, singly or in combination, improved predictive performance of a model that included acute physiology and longitudinal comorbidity burden (area under the receiver operator characteristic curve was 0.716 for both the EHR model and maximal performance of a random forest model including all predictors).Conclusions: In this insured population, incorporating patient-reported social factors and measures of cognitive and physical function did not improve performance of an EHR-based model predicting 30-day non-elective rehospitalization or mortality. While incorporating patient-reported social and functional status data did not improve ability to predict these outcomes, such data may still be important for improving patient outcomes. [ABSTRACT FROM AUTHOR]

Nowadays, the combination of hot casting and numerical control polishing is an effective and appreciated process to manufacture aero-engine turbine blades. However, casting is a hot forming process, and turbine blade will engender some geometric deviations compared to the design model, which results in a critical problem in subsequent numerical control polishing process. To solve this problem and reduce the rejection rate of blade blank, this manuscript attempts to present a novel process model reconstruction strategy in adaptive polishing of turbine blade. Firstly, the design model was sliced into several 2D sectional curves based on design manner, and these designed 2D sectional curves were measured separately using on-machine measurement (OMM) system. And then, the iterative closest point (ICP) was used to find the best position between the design model and the on-machine measurement points. Afterwards, appropriate geometrical tolerances of each 2D sectional curve were added into a constrained optimization model, which was established for finding the optimized sectional curve. Finally, the final process model was reconstructed by lofting these optimized sectional curves, which can be used for adaptive polishing. A typical turbine blade has been successfully performed to demonstrate the effectiveness and superiority of the proposed model reconstruction strategy. [ABSTRACT FROM AUTHOR]

We present an interesting relationship between the orthogonality catastrophe (OC) and the quantum speed limit (QSL) for a spin chain with uniform nearest neighbour couplings perturbed by an impurity spin. We thoroughly study the catastrophic QSL that specifies a bound on the evolution time between the initial and final states and in this respect, link it to the emerging OC effect. It is found that the speed of state evolution subtle but fundamental, and the bound characterized by QSL shows the same behaviours as the OC effect in the thermodynamic limit. It allows us to reveal some universal properties, in particular finite temperature effects. Significantly, the threshold of temperature and system size is clearly demonstrated for the QSL under finite temperature. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a prevalent joint disease that can be exacerbated by lipid metabolism disorders. The intra-articular fat pad (IFP) has emerged as an active participant in the pathological changes of knee OA (KOA). However, the proteomic and lipidomic differences between IFP tissues from KOA and control individuals remain unclear. Samples of IFP were collected from individuals with and without OA (n = 6, n = 6). Subsequently, these samples underwent liquid chromatography/mass spectrometry-based label-free quantitative proteomic and lipidomic analysis to identify differentially expressed proteins (DEPs) and lipid metabolites (DELMs). The DEPs were further subjected to enrichment analysis, and hub DEPs were identified using multiple algorithms. Additionally, an OA diagnostic model was constructed based on the identified hub DEPs or DELMs. Furthermore, CIBERSORT was utilized to investigate the correlation between hub protein expression and immune-related modules in IFP of OA. Our results revealed the presence of 315 DEPs and eight DELMs in IFP of OA patients compared to the control group. Enrichment analysis of DEPs highlighted potential alterations in pathways related to coagulation, complement, fatty acid metabolism, and adipogenesis. The diagnostic model incorporating four hub DEPs (AUC = 0.861) or eight DELMs (AUC = 0.917) exhibited excellent clinical validity for diagnosing OA. Furthermore, the hub DEPs were found to be associated with immune dysfunction in IFP of OA. This study presents a distinct proteomic and lipidomic landscape of IFP between individuals with OA and those without. These findings provide valuable insights into the molecular changes associated with potential mechanisms underlying OA. • The proteomic and lipidomic landscapes of IFP differ between healthy individuals and patients with KOA. • Proteins and lipids in the IFP exhibit differential expression, offering potential as early diagnostic markers for KOA. • The expression of core proteins in the IFP of KOA patients is linked to local immune infiltration. [ABSTRACT FROM AUTHOR]

Photovoltaic (PV)-powered alkaline electrolyzer system (PVPAES) is an advanced technique to convert the off-grid and intermittent PV-based solar energy into storable and transportable electrolyzer-based hydrogen energy with zero carbon emissions. However, it is difficult to realize the coordinated control of the off-grid PV module and the alkaline electrolyzer, due to the multiple timescale dynamics. To address this challenge, the PVPAES is decomposed into the slow part and fast part based on the dynamic time scale. Exploiting the decomposed subsystems, the slow one is assumed to be managed well by the auxiliary controller. For the fast one, a centralized economic model predictive control (CEMPC) scheme is constituted. This CEMPC integrates the energy management system and local feedback control into a single optimal control framework. A mathematical model of the PVPAES is established, on the basis of which the CEMPC directly adopts the economic indices as the cost function to realize the flexible power point tracking, power supply-demand balance, and dynamic economic optimization. Moreover, the inherent strong nonlinearity of PVPAES results in the nonconvex mixed-integer nonlinear programming optimization problem in the CEMPC. The exhaustive search algorithm utilizing finite converter switching states is adopted to achieve the global economic optimum. The effectiveness of the proposed CEMPC controller is illustrated through simulations under varying irradiance conditions. • A CEMPC scheme is developed for a PV-powered alkaline electrolyzer system. • A converter-based mathematical model is constructed for the system. • An efficient algorithm is proposed to solve non-convex CEMPC optimization problem. • The CEMPC is validated by simulations under varying irradiance conditions. [ABSTRACT FROM AUTHOR]

Sea perch iridovirus (SPIV) infection causes severe disease of fish and has led to economic loss of the sea perch Lateolabrax japonicus aquaculture industry. In this study, severe pathological damage of SPIV-infected sea perch was observed; the relationship of SPIV infection, gut microbial community structure, and gut transcripts of sea perch were explored. SPIV infection could inhibit normal immune function of the gut. The expression levels of immune genes such as MHC I, MHC II, TCR, BCR, and IgM were down-regulated during SPIV infection. Intestinal immunosuppression breaks the balance between mucosal immunity and gut microbes. Opportunistic pathogens such as Lawsonella , Corynebacterium , and Achromobacter expanded substantially following SPIV infection. The abundance of potential probiotics in aquatic animals such as Romboutsia declined following SPIV infection. Intestinal microbial lipopolysaccharide biosynthesis and bacterial secretion related functions increased in SPIV infection and correlated with the expression of intestinal lipopolysaccharide binding protein (LBP), TLR5, IL-1β and other genes. These results suggest that gut microbes can stimulate the innate immune system and trigger an acute inflammatory response through LPS. In conclusion, we analyzed the interaction between SPIV infection and gut microbes and provided a basis for further studies on the mechanism of SPIV pathogenesis and treatment. • The animal model of SPIV-infected sea perch was constructed. • SPIV induced immune response of the gut was evaluated. • Interaction between SPIV infection and gut microbes in sea perch was explored. [ABSTRACT FROM AUTHOR]

The integration of hydrogen energy into a photovoltaic-dominated microgrid is now becoming a promising approach to improve the photoconversion efficiency and enhance the operating reliability. However, the energy management and power regulation of the Photovoltaic/Hydrogen DC microgrid face challenges due to the intermittency of photovoltaic (PV) power generation and the randomness of load. In this paper, a distributed economic model predictive control (DEMPC) scheme is developed for a PV/Hydrogen DC microgrid, which integrates the energy management, economic optimization, and power regulation into one optimal control framework. Based on the developed distributed converter-based mathematical model, three local controllers are designed to achieve the economic targets of PV subsystem, alkaline electrolyzer subsystem, and proton exchange membrane fuel cell subsystem respectively, which cooperate with each other through the communication network to realize the power supply–demand balance, DC bus voltage stability, and economic optimization. A mixed integer nonlinear programming algorithm utilizing the finite converter switching states is embedded into the DEMPC to solve the non-convex local optimization problems efficiently. The effectiveness and superiority of the proposed DEMPC scheme are verified by simulations under varying irradiance and load conditions, indicating that the DEMPC can achieve a comparable overall dynamic economic performance with a significantly reduced computation burden and power oscillation, compared to the centralized economic model predictive control (CEMPC). • A DEMPC scheme is developed for a PV/Hydrogen DC microgrid. • An EMS is incorporated into the proposed DEMPC scheme. • An efficient algorithm is proposed to solve non-convex DEMPC optimization problem. • The DEMPC is validated by simulations under varying irradiance and load conditions. [ABSTRACT FROM AUTHOR]

The integration of hydrogen energy into a photovoltaic-dominated microgrid is now becoming a promising approach to improve the photoconversion efficiency and enhance the operating reliability. However, the energy management and power regulation of the Photovoltaic/Hydrogen DC microgrid face challenges due to the intermittency of photovoltaic (PV) power generation and the randomness of load. In this paper, a distributed economic model predictive control (DEMPC) scheme is developed for a PV/Hydrogen DC microgrid, which integrates the energy management, economic optimization, and power regulation into one optimal control framework. Based on the developed distributed converter-based mathematical model, three local controllers are designed to achieve the economic targets of PV subsystem, alkaline electrolyzer subsystem, and proton exchange membrane fuel cell subsystem respectively, which cooperate with each other through the communication network to realize the power supply–demand balance, DC bus voltage stability, and economic optimization. A mixed integer nonlinear programming algorithm utilizing the finite converter switching states is embedded into the DEMPC to solve the non-convex local optimization problems efficiently. The effectiveness and superiority of the proposed DEMPC scheme are verified by simulations under varying irradiance and load conditions, indicating that the DEMPC can achieve a comparable overall dynamic economic performance with a significantly reduced computation burden and power oscillation, compared to the centralized economic model predictive control (CEMPC). • A DEMPC scheme is developed for a PV/Hydrogen DC microgrid. • An EMS is incorporated into the proposed DEMPC scheme. • An efficient algorithm is proposed to solve non-convex DEMPC optimization problem. • The DEMPC is validated by simulations under varying irradiance and load conditions. [ABSTRACT FROM AUTHOR]

Driven by the high energy demand and environmental concerns, biodiesel as a substitute for fossil fuels is recognized as promising renewable and clean energy. Biodiesel has gained interest around the world over the last few years because it could be used to reduce most regulated exhaust emissions. Herein, we discuss the application of catalytic transesterification by using ionic liquids (ILs) catalyst with alcohol and waste oil for the clean synthesis of biodiesel in order to reduce the emission of NO x and CO. However, the running cost of this process is still higher than that of the conventional chemical transesterification. Non-edible sources such as waste oil, non-edible vegetable oil, and waste animal oil are commonly used to produce biodiesel due to their low cost and no dependency on the food chain. This review provides an overview of the recent progresses in improving the biodiesel production process by using ILs and determining the activation energy and the properties of the finished product. In addition, the future direction in biodiesel production via ILs catalysis in the transesterification has been discussed. • We review the catalytic activity of the various catalysts. • A biodiesel yield was achieved by using the ionic liquids with diethyl carbonate. • The ionic liquid with diethyl carbonate was shown to be the most efficient procedure. • The process can generate high purity green fuel that meets the quality demands. [ABSTRACT FROM AUTHOR]

Caragana is potentially an alternative biomass feedstock in China. The influences of different torrefaction conditions on the physical characteristics and fuel properties of pellets made from Caragana were investigated. The Caragana pellets were torrefied under the temperature of 225, 250, and 275 °C with the residence time of 10, 15, and 20 min, respectively. The results showed that the density of torrefied pellet reduced by 24.07 to 35.20%. Compression strength decreased to 7.62 N/mm2 for treated pellets under the condition of 275 °C and 20 min with the maximum weight loss of 29.93%, and the higher heating value increased to 20.95~22.93 MJ/kg. The equilibrium moisture content of the torrefied pellets decreased by 46.17% compared with raw materials. The mass yield and energy yield of torrefied pellet were 70.07 to 88.54% and 70.93 to 90.79%, respectively. With the increase of the torrefaction severity, the mechanical and physical properties of the pellets decreased, while the storage performance and fuel properties enhanced. Simultaneously, the torrefaction temperature had more influence on the fuel properties of Caragana pellets than the residence time. The Caragana pellets torrefied at 250 °C for 20 min maintained not only almost the same mechanical and physical properties as the untreated pellets but performed better storage and fuel properties. [ABSTRACT FROM AUTHOR]

This paper investigates the spin rate bounds, the configuration stability subject to the solar wind fluctuations, and sail angle control of an electric solar wind sail (E-sail) by a high-fidelity tether dynamic model. This model describes the elastic deformation of tethers with inter-connected 2-noded tensile elements discretized by the nodal position finite element method. The E-sail is assumed to be an axisymmetric system spinning in the plane normal to the heliocentric ecliptic plane. The upper and lower spin rate bounds are revisited to reveal the physics that dictates these bounds and analytic expressions are provided to ensure the proper operation of E-sail. Then, the influences of the solar wind fluctuations on the configuration stability of the E-sail are investigated by parametric analysis with different E-sail configurations, sail angles, and spin rates. Finally, an alternative sail angle control strategy for the E-sail is proposed by applying control force at the remote units with a simple PD control. Numerical analysis demonstrates that the sail angle of E-sail can be controlled quickly by the control law at the remote units with a high-precision. • Derived a new theoretical lower bound of spin rate for E-sail with auxiliary tethers. • Analyzed structural dynamics of E-sail by a high-fidelity tether dynamic model. • Revealed necessity and effectiveness of auxiliary tethers by tether dynamic perspective. • Controlled sail angle by applying control forces at remote units only. [ABSTRACT FROM AUTHOR]

The partial space elevator is a space transportation system that conveys cargo by a climber moving along the tether that connects the main satellite and the end body. This work proposed a novel prescribed performance based dual-loop control strategy for configuration keeping of the partial space elevator in cargo transportation. The control loop I controls the libration angle of the climber by a newly proposed prescribed performance control law to track the desired state with bounded performance. The Lyapunov stability of the control law is proved analytically. Control loop II stabilizes the overall configuration of the PSE by applying thrust and deploying/retrieving the tether simultaneously at the end body. To enforce the constraint that the total tether length is unchanged at the end of transportation, an event-triggered loaning control algorithm is proposed to further improve the Control loop II. Numerical simulations validate the prescribed performance based dual-loop control strategy. The results show that the stable configuration of the PSE is kept effectively with no libration motion in the period of cargo transportation. • A new dual-loop control strategy to keep PSE configuration in cargo transportation. • A prescribed performance control law to keep the climber's libration angle. • An event-triggered loaning control to incorporate configuration constraint. [ABSTRACT FROM AUTHOR]

Spacecraft formation maneuvering will inevitably induce flexible vibration from flexible appendages of spacecraft such as solar array appendages or antennae, which leads to complex disturbances with unknown fundamental frequencies. To achieve high performance of spacecraft formation flying, a novel adaptive iterative learning disturbance observer based on adaptive notch filter is designed to estimate and compensate unknown multi-frequency disturbances. Different from existing results on iterative learning disturbance observer, the newly proposed observer can estimate effectively both low-frequency disturbances and high-frequency periodic disturbances. Based on the proposed observer, an output feedback pose tracking law is derived by combining the proposed velocity observer and a feedback controller in dual quaternions description. The stability of the closed-loop system is approved based on the Lyapunov framework. Finally, the effectiveness and accuracy of the proposed observer and controller are demonstrated successfully by numerical simulations. • Developed a novel adaptive iterative learning control for flexible spacecraft formation. • Developed adaptive iterative learning observer to estimate multi-frequency disturbances. • Formulated 6DOF spacecraft formation maneuvering by dual quaternions. [ABSTRACT FROM AUTHOR]

• The tether tension's estimation issue of the PSE has been solved. • A speed function has been derived to plan the climber speed at desired state. • A novel observer-based control scheme has been proposed for multiple actuators. This work proposes a novel hybrid control scheme to stabilize a partial space elevator with unknown tether tensions in cargo transportation. The tether tensions are first estimated by a new observing method. The control scheme contains two controllers. With the estimated tensions, Controller I predicts the optimal reference climber speed implemented by the actuator on the climber. When the climber is moving at the reference speed, a novel observer-based super twisting sliding mode control law is proposed for Controller II to eliminates possible disturbances and further stabilises the system in real-time. Simulation results reveal that with the observed tensions, the proposed hybrid control scheme is very effective and accurate in stabilizing the partial space elevator actuated by multiple actuators in the cargo transfer period. [ABSTRACT FROM AUTHOR]

To quantify the dose-response associations between tooth loss and risk of cognitive impairment and dementia. Longitudinal studies that examined the association between tooth loss and cognitive function were systematically searched on 6 databases through March 1, 2020. The study adhered to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guidelines. Risk estimates were pooled using random-effects models. The dose-response associations were assessed using generalized least squares spline models. Adults from community, institution, outpatient or in-hospital were included in the meta-analysis. Cognitive impairment and dementia were defined by neuropsychological tests, diagnostic criteria, or medical records. Tooth loss was self-reported or assessed by clinical examinations. Fourteen studies were entered into the meta-analysis, including 34,074 participants and 4689 cases with diminished cognitive function. Participants with more tooth loss had a 1.48 times higher risk of developing cognitive impairment [95% confidence interval (CI) 1.18–1.87] and 1.28 times higher risk of being diagnosed with dementia (95% CI 1.09–1.49); however, the association was nonsignificant for participants using dentures (relative risk = 1.10, 95% CI 0.90–1.11). Eight studies were included in the dose-response analysis, and data supported the use of linear models. Each additional tooth loss was associated with a 0.014 increased relative risk of cognitive impairment and 0.011 elevated relative risks of dementia. Edentulous participants faced a 1.54 times higher risk of cognitive impairment and a 1.40 times higher risk of being diagnosed with dementia. Moderate-quality evidence suggested tooth loss was independently associated with cognitive impairment and dementia; risk of diminished cognitive function increased with incremental numbers of teeth lost. Furthermore, timely prosthodontic treatment with dentures may reduce the progression of cognitive decline related to tooth loss. [ABSTRACT FROM AUTHOR]

As one of the most important part of an aero-engine, blade has a critical effect on its manufacturing level. Especially, surface quality and profile accuracy of the leading and trailing edges have a direct influence on the aerodynamic performance of an aero-engine. At present, the machining methods of the leading and trailing edges are milling or grinding firstly, and then polishing by hand. This combination pattern of milling or grinding and polishing by hand has low efficiency and poor consistency. Therefore, a novel polishing technology for leading and trailing edges of blade using the flexible polishing wheel is proposed in this manuscript. Firstly, the overview of proposed novel polishing technology is presented. And then the basic principle and flexible polishing law of the flexible polishing wheel are introduced and analyzed. Finally, the verification experiments are carried out, including sample verification and blade verification. And the experiments results validate the feasibility of the proposed polishing technology. This novel polishing technology which instead of combination pattern of milling and polishing can simultaneously guarantee both profile accuracy and surface roughness, and the machining efficiency of blade edges will improve 2 times than the conventional method. [ABSTRACT FROM AUTHOR]

Background: An increasing number of people living with HIV (PLWH) have had chronic noncommunicable diseases (NCDs) over the last 5 years. However, robust evidence regarding the perception and challenges of having NCDs among PLWH is limited. Therefore, this study aimed to synthesize qualitative evidence regarding the experiences of PLWH with NCDs.Methods: We used a meta-aggregation approach to synthesize qualitative studies. Peer-reviewed and gray literature published in English and Chinese from 1996 to November 2020 was searched using electronic databases. Two reviewers independently appraised the methodological quality and extracted data from the included studies. The Joanna Briggs Institute (JBI) meta-aggregation approach was used to synthesize the findings.Results: In total, 10,594 studies were identified in the initial database search. Fourteen eligible studies were included in the meta-synthesis. Among these studies, nine synthesized findings regarding the following topics were identified: fragmented healthcare systems, care continuity, manifestations of multiple conditions, financial hardship, stigma and discrimination, polypharmacy burden and adherence, reciprocal relationships between HIV and NCDs, and coping strategies.Conclusions: In recent years, attempts have been made to institutionalize NCD preventive and control services in HIV long-term care. However, considering the growing problem of HIV and NCD comorbidity globally, integrated primary health care systems are needed to address the problems of PLWH with NCDs. Healthcare professionals should help PLWH develop strategies to better monitor their polypharmacy burden and adherence, stigma and discrimination, financial hardship, and manifestations of multiple conditions to achieve high levels of care continuity. [ABSTRACT FROM AUTHOR]

The impacts of COVID-19 on travel demand, traffic congestion, and traffic safety are attracting heated attention. However, the influence of the pandemic on electric bike (e-bike) safety has not been investigated. This paper fills the research gap by analyzing how COVID-19 affects China's e-bike safety based on a province-level dataset containing e-bike safety metrics, socioeconomic information, and COVID-19 cases from 2017 to 2020. Multi-output regression models are adopted to investigate the overall impact of COVID-19 on e-bike safety in China. Clustering-based regression models are used to examine the heterogeneous effects of COVID-19 and the other explanatory variables in different provinces/municipalities. This paper confirms the high relevance between COVID-19 and the e-bike safety condition in China. The number of COVID-19 cases has a significant negative effect on the number of e-bike fatalities/injuries at the country level. Moreover, two clusters of provinces/municipalities are identified: one (cluster 1) with lower and the other (cluster 2 that includes Hubei province) higher number of e-bike fatalities/injuries. In the clustering-based regressions, the absolute coefficients of the COVID-19 feature for cluster 2 are much larger than those for cluster 1, indicating that the pandemic could significantly reduce e-bike safety issues in provinces with more e-bike fatalities/injuries. [ABSTRACT FROM AUTHOR]

Background: The American Thoracic Society (ATS) guideline for methacholine challenge testing (MCT) recommended using the English Wright (EW) nebuliser. However, other brands of nebulisers are also indicated to be acceptable for this technique, but further validation of nebuliser performance is recommended. Objective: To compare the methacholine provocation concentration causing a 20% fall in forced expiratory volume in 1 second (PC20‐FEV1) measured by using EW nebuliser and DV 646 nebuliser. Methods: Subjects were randomly assigned to undergo 2‐min tidal breathing methacholine challenge with either EW or DV 646 nebuliser on two separate days, which were at least 24 hours but not more than 7 days apart. The above procedure was repeated for each subject in 1 month, but the nebulisers were selected in a reverse order. Results: The study includes 15 mild and stable asthmatic patients. The geometric means (SD) of methacholine PC20 measured with using EW and DV 646 nebulisers were 1.82 (6.38) mg/mL versus 0.83 (1.82) mg/mL, respectively in the initial two visits and 2.56 (6.29) mg/mL versus 0.78 (1.40) mg/mL in the following two visits (both P < 0.05). There are well correlations between PC20‐EW1 and PC20‐EW2 (r = 0.99, P < 0.01), PC20‐DV1 and PC20‐DV2 (r = 0.88, P < 0.01), and between PC20‐EW1 and PC20‐DV1 (r = 0.91, P < 0.01), PC20‐EW2 and PC20‐DV2 (r = 0.78, P < 0.01). Conclusions: PC20‐FEV1 measured by using the two conventional jet nebulisers was both repeatable and the results were highly correlated. [ABSTRACT FROM AUTHOR]