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With the connection and integration of renewable energy, the on-load tap-changer (OLTC) has become an important device for regulating voltage in distribution networks. However, due to non-smooth and non-linear characteristics of OLTC, traditional bad data identification and state estimation methods for transmission network are limited when applied to the distribution network. Therefore, the nonlinearity and droop control constraints of the OLTC model are considered in this paper. At the same time, the quadratic penalty function is introduced to realize the fast normalization of the tap position. It proposes a two-stage bad data identification method based on mixed-integer linear programming. In the first stage, suspicious measurements are identified using projection statistics and maximum normalized residual methods for preprocessing the measurement data. In the second stage, a linearization approach utilizing hyhrid data-physical driven is applied to handle nonlinear constraints, leading to the development of a bad data identification model based on mixed-integer linear programming. Finally, the proposed methodology is validated using a modified IEEE-33 node test feeder example, demonstrating the accuracy and efficiency of bad data identification. [ABSTRACT FROM AUTHOR]

Fossil fuels remain indispensable energy resources despite their non-renewable nature. Understanding the patterns of global fossil fuel consumption is essential for energy security and policy-making. This study employs complex network theory and fractal time series analysis to explore the underlying dynamics and patterns of fossil fuel consumption globally, with a focus on coal, oil, and gas consumption. The study applies the Hurst index to raw fossil fuel consumption data to identify fractal characteristics. Additionally, the visibility graph method is used to convert time series data into complex networks, allowing further analysis of consumption patterns. The study examines fossil fuel consumption in 38 countries to assess global trends and differences. The analysis reveals that global fossil fuel consumption follows a fractal time series pattern, with Hurst index values exceeding 0.9, indicating long-term memory characteristics. The application of the visibility graph method demonstrates variations in the Hurst index of degree distribution, enabling the differentiation of consumption patterns across regions. The method also uncovers distinct features of coal, oil, and gas consumption when viewed from a network perspective. The findings suggest that fossil fuel consumption has predictable long-term patterns, which are crucial for assessing future energy demands. The study highlights the importance of legislative measures to safeguard fossil fuel resources, especially for countries like China, where energy security and international competitiveness are paramount. Understanding these consumption patterns could guide future energy policies aimed at managing non-renewable resources more effectively. [ABSTRACT FROM AUTHOR]

Inflammatory bowel disease (IBD) encompasses a collection of chronic inflammatory conditions impacting the gastrointestinal tract, with a discernible global rise in prevalence and severity. The overabundance of reactive oxygen species (ROS) in the intestinal environment leads disruption of local redox homeostasis, and perturbation of the gut microbiota, exacerbating IBD. Consequently, mitigating excess ROS and preserving gut microbiota homeostasis have emerged as effective approaches for IBD management. In this study, a triangular DNA origami nanostructure loaded with siRNA targeting tumor necrosis factor α (siTNF‐αtDON) is introduced for this purpose. This nanostructure demonstrates efficacy in eliminating ROS within cells closely associated with IBD, diminishing inflammation, and ameliorating disorders in gut microbiota, as evidenced in an IBD mouse model. Furthermore, this investigation demonstrates the effects of siTNF‐αtDON on related inflammatory signaling pathways, including NF‐κB, MAPK/ERK and Keap1/Nrf2. Collectively, this study offers insights into the potential utilization of DNA nanostructures as antioxidants and gut microbiota modulators, presenting promising avenues for the IBD treatment. [ABSTRACT FROM AUTHOR]

Objectives: Tibial tubercle is a crucial player in maintaining the structural integrity and functional stability of the knee joint. Currently, there is no standardized protocol for the classification and treatment of tibial tubercle fractures in adults. This study analyzed the incidence and treatment strategies of tibial tubercle fractures in adults according to the four‐column and nine‐segment classification system. Methods: Data of patients with proximal tibial fractures involving tibial tubercle fractures who were treated at our hospital from August 2007 to March 2023 were retrospectively reviewed. The fractures were classified using the AO/OTA classification and four‐column and nine‐segment classification systems, and the treatment protocol (surgically treated or conservatively treated) was recorded. The number and distribution proportion of patients were counted. A two‐sided t‐test was conducted to determine the significance of differences between the gender and sides. Results: In total, 169 tibial tubercle fractures were found in 1484 proximal tibial fractures. According to the AO/OTA classification, seven of the 169 patients, (4.1%) were type A, 36 patients (21.3%) were type B, and 126 patients (74.6%) were type C. According to the four‐column and nine‐segment classification, type 1 cleavage without free fragments was the most common type of fracture (93/169, 55.0%), followed by type 2 dissociative segmental fragments (48/169, 28.4%) and type 3 comminuted fractures (28/169, 16.6%). Overall, 139 of the 169 proximal tibial fractures with tuberosity involvement were treated surgically. Among them, additional fixation of the tubercle fragment was performed in 52 fractures. Conclusion: The incidence of tibial tubercle fractures involved in proximal tibial fractures was approximately 11.4% (169/1484) in adults, and approximately one‐third of the tubercle bone fragment required additional fixation (30.8%, 52/169). The injury types in the four‐column and nine‐segment classifications are helpful for accurately judging and making treatment‐related decisions for tibial tubercle fractures. [ABSTRACT FROM AUTHOR]

Background: Tree seedling regeneration in forests is often hindered by the competitive influence of dense understory bamboo competition. While localized studies have investigated the ecological effects of understory bamboo removal on tree seedlings, a comprehensive analysis at a global scale is lacking. In this meta-analysis, we synthesized 497 observations from 32 experimental studies to assess the overall effects of understory bamboo removal on tree seedling regeneration. Results: The results showed that understory bamboo removal enhanced tree seedling survival, emergence, and height growth. However, the response of tree seedlings to bamboo removal varied depending on regeneration characteristics, forest types, and bamboo removal methods. Specifically, understory bamboo removal increased the survival rate of deciduous seedlings but had no significant effect on evergreen seedlings. For regeneration stages, bamboo removal had a significant positive effect on the survival rate of saplings but not on seedlings. Regarding differences across forest types, bamboo removal significantly increased the emergence density of seedlings in deciduous broadleaf forests but had a significant negative influence in evergreen and mixed evergreen-deciduous forests. Additionally, natural removal of bamboo showed a greater positive effect on seedlings than bamboo removal by artificial or animal gnawing methods. Furthermore, we found that the duration of bamboo removal, mean annual temperature, precipitation of seasonality, and soil pH strongly influenced the response ratios of tree seedling regeneration. Conclusions: Our meta-analysis demonstrates the significant effects of understory bamboo removal on multiple facets of tree seedling dynamics across different regeneration characteristics, forest types, and bamboo removal methods. In addition, our study emphasizes that the duration of bamboo removal, climate, and soil pH have a critical effect on tree seedling regeneration. Our findings elucidate the effects of understory bamboo removal on seedling regeneration, offering robust scientific insights for sustainable forest management. [ABSTRACT FROM AUTHOR]

Antibiotic residues in water represent an urgent environmental challenge. To efficiently remove these residues, a low‐carbon integrated biochar synthesis method was proposed, and an optimized typha biochar (TBIK) was prepared. Compared with the biochar prepared by a conventional two‐step carbonization and activation method (TBTK), the TBIK preparation process reduced energy consumption by 43849.58 J and cut carbon dioxide emissions by 32.80%. TBIK exhibited a large surface area of 1252.40 m2/g and rapidly achieved an equilibrium removal efficiency of 99.95% within 20 min for simulated antibiotics wastewater. Furthermore, TBIK possessed more number of functional groups than TBTK, especially O‐H and C‐S groups. The adsorption stability and tolerance of TBIK in solutions with different ionic strengths and coexisting anions were examined. Characterization techniques such as scanning electron microscopy (SEM), Fourier transform infrared (FT‐IR), and X‐ray photoelectron spectroscopy (XPS) as well as Brunauer, Emmett and Teller (BET) analyses were employed to elucidate the morphology and adsorption mechanism of the adsorbent. The microporous structure and abundance of functional groups are key to the excellent adsorption capabilities of TBIK. Thus, this integrated method for biochar production, optimized for treating antibiotic wastewater, holds significant potential for future applications. [ABSTRACT FROM AUTHOR]