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Abstract Economic and social factors pose an enormous threat to forest ecological security, which in turn affects the development of ecological civilization. This paper applies a geographically weighted regression model to study the impact of urbanization, industrial structure, and foreign direct investment on forest ecological security of 30 provinces in 2013 and 2018 and reveals the spatial differences of various influencing factors in different provinces. First, the overall forest ecological security in China is at an average level, with slight improvement. Second, urbanization has the greatest impact on forest ecological security in all provinces, which shows a rising trend. Third, the positive impact of industrial structure on forest ecological security has improved. Fourth, in 2013, FDI (foreign direct investment) had a negative correlation with forest ecological security. In 2018, FDI had a positive impact on the forest ecological security index of 16 provinces, while it had a negative correlation in other provinces. Therefore, it is necessary to formulate a coordinated security improvement plan for neighboring provinces. The government should promote rural revitalization, plan the layout of cities rationally, increase the proportion of tertiary industry, appropriately raise access barriers to foreign investment and strengthen environmental supervision over existing foreign-invested enterprises.

Abstract Over the past two decades, the surge in warehouse construction near seaports and in economically lower‐cost land areas has intensified product transportation and e‐commerce activities, particularly affecting air quality and health in nearby socially disadvantaged communities. This study, spanning from 2000 to 2019 in Southern California, investigated the relationship between ambient concentrations of PM2.5 and elemental carbon (EC) and the proliferation of warehouses. Utilizing satellite‐driven estimates of annual mean ambient pollution levels at the ZIP code level and linear mixed effect models, positive associations were found between warehouse characteristics such as rentable building area (RBA), number of loading docks (LD), and parking spaces (PS), and increases in PM2.5 and EC concentrations. After adjusting for demographic covariates, an Interquartile Range increase of the RBA, LD, and PS were associated with a 0.16 μg/m³ (95% CI = [0.13, 0.19], p

In this paper, the global stabilization problem of control systems with input saturation and multiple input delays is studied, and a new method is proposed to design nonlinear stabilization control laws. First, based on Luenberger’s canonical decomposition, the multiple-input delay system is transformed into a series of linear time-delay systems with single inputs and input saturation. However, for the converted system, each subsystem is coupled to the others. Therefore, the idea of recursion is adopted to construct a special state transformation with time delay for each subsystem and convert it into a linear system with time delay for both state variables and input variables. For the conversion system, a nonlinear controller with cascade saturation control is designed, and the controller includes some free parameters. The control performance of the controller is improved by adjusting the free parameters online. At the same time, a less conservative stability condition is established to ensure the dynamic performance of the closed-loop system. Finally, the effectiveness and superiority of the proposed method are verified by numerical simulation and practical applications in a spacecraft rendezvous system.

Many free-floating bicycle-sharing (FFBS) operators in cold region cities will put bicycles in warehouses and suspend services in winter due to factors such as safety and maintenance costs, resulting in the corresponding travel demand no longer be met. Considering the short-distance and green travel characteristics of FFBS, the flexible bus, as a sustainable demand-responsive transit service, is a suitable alternative transportation mode. To operate such a flexible bus system, service area and operation time planning is a key stage, however, the planning methods in relevant studies are not suitable for this research scenario. In view of the above, this paper proposed a data-driven method to determine the service area and operation time of flexible buses based on FFBS data. Firstly, an FFBS trip path reconstruction algorithm consists of fine-grained road network modelling and trajectory matching is proposed. Then, in the defined time slice, incorporating the idea of ride-sharing routes generation, according to the density-based clustering principle and considering topology between trajectories, a path clustering algorithm PATHSCAN is developed to generate the one-day path clusters. After that, a frequent pattern mining algorithm is applied to the multiday path clusters, and frequent pattern results with spatio-temporal correlation will be merged into the final service area. The generated planning results will cover ride-matching trips and high-frequency riding paths. Detailed application analysis and verification are carried out by using the real data from Tianjin, China. Through the evaluation and verification under the relatively limited experimental data set, the proposed data-driven method shows ideal planning results. Flexible bus service can supplement the green short-distance travel mode after the suspension of FFBS and can avoid FFBS travel demands switched to unsustainable transportation modes to a large extent. This study will contribute to urban sustainable transportation development and improving greenness.

Abstract Objective To assess the utility of the preoperative Sarcopenia index (SI) as a predictive marker of the risk of postoperative complications following hip fracture surgery in older adults. Study design This observational study enrolled older adults with hip fracture who were hospitalized in the Department of Orthopedics of West China Hospital, Sichuan University, from December 7, 2010 - June 14, 2017, and who underwent hip fracture surgery. Primary outcome and measures Clinical data were collected from medical records and serum creatinine and cystatin C were measured before surgery. Outcomes included postoperative complications such as pneumonia, urinary tract infection, respiratory failure, heart failure, and non-grade A healing. Binary logistic regression analyses were used to analyze association between SI and postoperative complications. Results A total of 897 patients aged 60 years and over were enrolled in this study (age range: 60 – 100 years), of whom 306(34.1%)were male, and 591(65.9%)were female. Postoperative complications included pneumonia (12%), urinary tract infections (1.8%), respiratory failure (1.5%), heart failure (1.6%), and non-A- grade healing (3.6%). In the patient group that received joint replacements, the incidence of pneumonia was negatively associated with SI values. After adjusting for potential confounding factors, binary logistic regression analyses showed that a higher SI was independently associated with a lower risk of pneumonia after joint replacement surgery (OR:0.39, 95% CI:0.18-0.89, P

Recent trends show a steady progression in the normalization of online learning. While online learning environments offer students flexibility and convenience, the lack of self-regulation has become a significant factor that could influence online learners' learning experiences and academic outcomes. This literature review provides a comprehensive picture of experimental studies of self-regulated learning (SRL) interventions and postsecondary students' self-regulatory processes in online contexts between 2000-2020. Detailed analysis of 17 experimental studies found that SRL interventions that proved to be effective in online learning coalesced into 3 themes: conceptual, metacognitive, and instrumental supports. Findings from this synthesis can guide instructors to infuse effective self-regulation interventions and prompt researchers to investigate SRL more deeply in online learning environments. [ABSTRACT FROM AUTHOR]