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Amidst urbanization and industrialization in China, abandoned farmland plays a crucial role in safeguarding plant diversity within agricultural landscapes. This study aimed to examine the patterns of seasonal variation in plant diversity within abandoned farmland habitats in the Huang–Huai Plain region. Nonparametric tests were employed to analyze plant species diversity and phylogenetic diversity across seasons. Redundancy analysis and linear regression were conducted to examine the associations between plant species composition, species diversity, phylogenetic diversity, and soil environmental factors. Our results showed that plant species diversity, richness, and phylogenetic diversity were highest in spring, followed by summer, and lowest in autumn. The phylogenetic structure of plant communities demonstrated a tendency to diverge in spring, become random in summer, and cluster in autumn. Soil available potassium and soil organic matter emerged as important factors influencing plant species composition. The content of soil organic matter and ammonium nitrogen level exhibited a significantly positive correlation with the species diversity and phylogenetic diversity of plants. This study underscores the significance of considering seasonal and temporal scales when investigating plant diversity and provides a theoretical basis for biodiversity conservation in agricultural landscapes. [ABSTRACT FROM AUTHOR]

This study focuses on the significance of improving the land degradation of Mu Us Sandy Land to increase cultivated land area and promote ecological green development. The research objects were four kinds of mixed soils, and rhizosphere soils were collected during the crop harvesting period. The volume ratio of soft rock to sand was 0:1 (control check, CK), 1:5 (composite soil one, PS1), 1:2 (composite soil two, PS2), and 1:1 (composite soil three, PS3). The results showed that the large aggregates were primarily mechanically stable aggregates, while the small aggregates were mainly water-stable aggregates. The soft rock promoted the increase of clay and silt content in sandy soil, and the soil texture changed from sand to loam. The contents of organic matter, available phosphorus, and available potassium increased significantly under PS2 and PS3 treatments, but there was no significant difference between them. Total nitrogen had no significant difference among treatments. Actinobaciota, Proteobateria, and Chloroflexi were the dominant bacteria in rhizosphere soil, accounting for about 75% of all microorganisms. At the Genus level, the soft rock contributes to richer species composition. The diversity index, evenness index, and richness index was higher in PS1, and the available phosphorus and available potassium content promoted the increase of diversity. Therefore, when the proportion of soft rock and sand compound soil is between 1: 5 and 1: 2, it can be used as an important basis and technical parameter for Mu Us Sandy Land improvement. [ABSTRACT FROM AUTHOR]

China is an ancient civilization. History has left us with a rich cultural heritage, of which ancient cultural sites account for a large proportion. As far as the current scientific research and technology are concerned, due to the particularity and complexity of the humid environment, the protection of ancient cultural sites in the humid environment is still an important topic before us. The research topic involved in this article is about the application of composite nano-calcium-based materials for the reinforcement and protection of soil sites in humid environments. Combined with the development of the research content of this article, the research thinking of the thesis is also adjusted accordingly, making the analysis and solution of the problem clearer. The first is a conceptual study, expounding the relevant concepts in this article. The main purpose is to sort out and study the reinforcement and protection measures and methods of relevant sites and ancient cultural sites, as well as the classification, characteristics, and protection value of ancient cultural sites. Through the analysis and research of these aspects, the composite nano-calcium bases for ancient cultural sites in the subsequent humid environment is proposed based on material basic information. The second is a descriptive research, qualitative and quantitative analysis of humid environment. On the basis of summarizing previous researches, this paper mainly conducts qualitative and quantitative analysis on the judgment of humid environment, the influence mechanism on ancient cultural sites, and the main diseases. Then, it is analytical research, studying the main diseases and causes of the underground palace site in the engineering case, and it is concluded that it is mainly affected by the combined effect of the characteristics of the site's soil and the environment. Through the collection of data from the site survey, field test, and indoor experiment of the underground palace site, the preservation status of the site is collected, and the disease problems faced by the site were analyzed, making it more difficult to protect. The main problem facing the protection of soil relics in humid environment, that is, the research focus, is the research on the development and applicability of reinforcement protection materials. This article attempts to explore the protective effect of composite nano-calcium-based materials on wet sites. Practical research was conducted to verify the feasibility of composite nano-calcium-based materials in practice through indoor site soil simulation. After the completion of a series of experiments, the applicability and compatibility of the composite nano-calcium-based material to strengthen the wet site soil was verified through data analysis, data collection, and mechanism discussion. The experimental results show that the sample with a solid content of 0.4% composite nano-calcium matrix has better salt and alkali resistance. Moreover, the unconfined compressive strength growth rate of 0.4% of the samples has a qualitative improvement over other solid content samples. [ABSTRACT FROM AUTHOR]

Plant growth environment plays an important role in shaping soil microbial communities. To understand the response of soil rhizosphere microbial communities in Oplopanax elatus Nakai plant to a changed growth conditions from natural habitation to cultivation after transplant. Here, a comparative study of soil chemical properties and microbial community using high-throughput sequencing was conducted under cultivated conditions (CT) and natural conditions (WT), in Changbai Mountain, Northeast of China. The results showed that rhizosphere soil in CT had higher pH and lower content of soil organic matter (SOM) and available nitrogen compared to WT. These changes influenced rhizosphere soil microbial communities, resulting in higher soil bacterial and fungi richness and diversity in CT soil, and increased the relative abundance of bacterial phyla Acidobacteria, Chloroflexi, Gemmatimonadetes, Firmicutes and Patescibacteria, and the fungi phyla Mortierellomycota and Zoopagomycota, while decreased bacterial phyla Actinobacteria, WPS-2, Gemmatimonadetes, and Verrucomicrobia, and the fungi phyla Ascomycota, and Basidiomycota. Redundancy analysis analysis indicated soil pH and SOM were the primarily environmental drivers in shaping the rhizosphere soil microbial community in O. elatus under varied growth conditions. Therefore, more attention on soil nutrition management especially organic fertilizer inputs should be paid in O. elatus cultivation. [ABSTRACT FROM AUTHOR]

Background: Regional lymph node metastasis is a contributor for poor prognosis in osteosarcoma. However, studies on risk factors for predicting regional lymph node metastasis in osteosarcoma are scarce. This study aimed to develop and validate a model based on machine learning (ML) algorithms. Methods: A total of 1201 patients, with 1094 cases from the surveillance epidemiology and end results (SEER) (the training set) and 107 cases (the external validation set) admitted from four medical centers in China, was included in this study. Independent risk factors for the risk of lymph node metastasis were screened by the multifactorial logistic regression models. Six ML algorithms, including the logistic regression (LR), the gradient boosting machine (GBM), the extreme gradient boosting (XGBoost), the random forest (RF), the decision tree (DT), and the multilayer perceptron (MLP), were used to evaluate the risk of lymph node metastasis. The prediction model was developed based on the bestpredictive performance of ML algorithm and the performance of the model was evaluatedby the area under curve (AUC), prediction accuracy, sensitivity and specificity. A homemade online calculator was capable of estimating the probability of lymph node metastasis in individuals. Results: Of all included patients, 9.41% (113/1201) patients developed regional lymph node metastasis. ML prediction models were developed based on nine variables: age, tumor (T) stage, metastasis (M) stage, laterality, surgery, radiation, chemotherapy, bone metastases, and lung metastases. In multivariate logistic regression analysis, T and M stage, surgery, and chemotherapy were significantly associated with lymph node metastasis. In the six ML algorithms, XGB had the highest AUC (0.882) and was utilized to develop as prediction model. A homemade online calculator was capable of estimating the probability of CLNM in individuals. Conclusions: T and M stage, surgery and Chemotherapy are independent risk factors for predicting lymph node metastasis among osteosarcoma patients. XGB algorithm has the best predictive performance, and the online risk calculator can help clinicians to identify the risk probability of lymph node metastasis among osteosarcoma patients. [ABSTRACT FROM AUTHOR]

Increasing carbon emissions efficiency (CEE) is essential for Chinese cities to achieve their dual carbon goals. For cities with higher CEE, it is crucial to comprehensively evaluate their carbon emissions reduction potential (CERP) and develop targeted carbon reduction paths. This study first determined the input, expected output, and non-expected output indicators and used the super-efficiency Slack Based Measure model to calculate the CEE of 336 cities. Secondly, we evaluated the urban development level, structural optimization space, and natural resource endowment using the BWM-CRITIC-TOPSIS method and combined them with CEE to evaluate the CERP. Finally, we used K-means clustering to group cities according to the carbon emissions level and CERP and proposed targeted emission reduction recommendations. The results showed that cities in the northern part of China had lower CEE, while the coastal areas had higher CEE. In the primary indicators of CERP, structural optimization space was the most important, followed by efficiency improvement space. The eastern region has a greater potential for carbon reduction, with an average score of 63.71 points (out of 100 evaluation points) for the 336 cities. The cities could be classified into nine types, with the ninth category being the key focus cities for achieving the 2030 carbon peak goal with high carbon emissions and CERP. [ABSTRACT FROM AUTHOR]

The coordinated development of upstream, midstream, and downstream of wind power industry chain is the key to solve the problem of wind power consumption. Therefore, this paper firstly constructs the performance evaluation index system of the upstream, midstream, and downstream of the wind power industry chain, and evaluates the performance of the upstream, midstream, and downstream of the wind power industry based on entropy weight-TOPSIS. Secondly, the coupling coordination degree (CCD) model between subsystems of wind power industry chain is established to dynamically evaluate the CCD between upstream and midstream, midstream and downstream, and among three subsystems of wind power industry chain. Finally, taking the development data of China's wind power industry from 2010 to 2019 as an example, the coupling coordination degree between subsystems is empirically studied. The results show that: the overall performance of wind power industry chain has a tortuous upward trend; the coupling degree (CD) of each subsystem is better than that of 2011 and 2012; The CCD of upstream and midstream of wind power industry chain fluctuates more than that of midstream and downstream and that of three subsystems. • The performance evaluation index of the upstream, midstream and downstream of the wind power industry chain is established. • Entropy weight-TOPSIS method is used to evaluate the performance of wind power industry chain. • The coupling coordination degree model between subsystems of wind power industry chain is established. • The coupling coordination degrees between subsystems of wind power industry chain are dynamically evaluated. [ABSTRACT FROM AUTHOR]