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Land resources are essential natural resources and strategic economic resources for human survival and development. However, human improper use has brought unprecedented pressure and challenges to the ecosystem. Therefore, the assessment and analysis of land ecological security status and the identification and diagnosis of obstacles affecting land ecological security are helpful to avoid land ecological security problems caused by improper land use at the source and provide a theoretical basis for the sustainable use of land resources and the construction of ecological civilization in China. Based on the data from 2006 to 2020, this study constructed the land ecological risk-evaluation index system and land ecological health-evaluation index system. AHP, entropy method, combination weighting method, TOPSIS model, Boston matrix and obstacle degree model were used to assess the land ecological security situation in Nanyang City and to analyze the obstacle factors. The results show the following: (1) during the study period, the land ecological risk value of Nanyang City exhibited a Kuznets inverted "U" curve change, while the land ecological health value showed a "U" curve change; (2) the overall level of land ecological security in Nanyang City has gradually improved, with a security level pattern of "relatively safe (2006–2020)–unsafe (2011–2016)–relatively safe (2017–2019)–safe (2020)"; (3) the main obstacle factors of land ecosystem were the following: erosion area, sewage discharge, area of waterlogging control, grain sown area, coverage of urban green built-up area and farmland effective irrigated area. [ABSTRACT FROM AUTHOR]

Simple Summary: Currently, as a neoadjuvant conversion therapy (NCT), pazopanib combined with neoadjuvant chemoradiotherapy could improve the pathological response of unresectable soft tissue sarcoma (uSTS). However, there is no available evidence of its effectiveness with respect to tumor reduction and surgical margins. In China, anlotinib is a novel tyrosine kinase inhibitor (TKI) that is approved for STS. In this study, adding anlotinib to adriamycin and ifosfamide resulted in an increased rate of tumor regression, surgical conversion and R0 resection in patients with uSTS, particularly for synovial sarcoma and liposarcoma. Severe toxicities are more frequent than monotherapy, but they are controllable. (1) Background: This study investigated the safety and efficiency of adriamycin and ifosfamide combined with anlotinib (AI/AN) as a neoadjuvant conversion therapy in uSTS. (2) Methods: Patients with uSTS were eligible to receive AI/An, including adriamycin (20 mg/m2/d) and ifosfamide (3 g/m2/d) for the first to the third day combined with anlotinib (12 mg/d) for 2 weeks on/1 week off, all of which combine to comprise one cycle. Surgery was recommended after four cycles of treatment. (3) Results: A total of 28 patients were enrolled from June 2018 to December 2020. The best tumor responses included eight patients with partial responses and 20 with a stable disease. Patients with synovial sarcoma and liposarcoma had a significant decrease in the number of tumors compared with fibrosarcoma (p = 0.012; p = 0.042). The overall response rate and disease control rate were 28.57% and 100%, respectively. In total, 24 patients received surgery, while the rates of limb salvage and R0 resection were 91.67% (n = 22/24) and 87.50% (n = 21/24), respectively. Until the last follow-up visit, the mean PFS and RFS were 21.70 and 23.97 months, respectively. During drug administration, 67.87% of patients had grade ≥3 AEs. No treatment-related death occurred. (4) Conclusions: AI/AN followed by surgery showed favorable efficiency and manageable safety in patients with uSTS. A randomized controlled study with a large cohort should be performed for further investigations. [ABSTRACT FROM AUTHOR]

Coal is the mainstay of China's energy supply. With the gradual progress in China's policy of phasing out backward coal production capacity, the intensive and deep mining of coal has gradually become the new norm. The current mining depth is increasing at a rate of 10~15 m/year. The high crust stress, high gas pressure, high ground temperature, and engineering disturbance stress in deep coal mines can lead to the occurrence of coal–rock–gas dynamic disasters that are complex and show the characteristics of compound dynamic disasters. It is important to understand the evolution and mechanism of deep coal and rock dynamic disasters accurately for the safe development of deep resources. To study the mechanism of occurrence and the evolution of impact–protrusion compound dynamic disasters, we herein analyzed the apparent characteristics of coal–rock–gas compound dynamic disasters in deep mines and obtained the mechanical and acoustic emission characteristics of coal–rock composites through indoor experiments. Then, we conducted in-depth analysis on the non-uniform deformation behaviors and non-uniform stress field of the coal–rock composite and clarified the generation mechanism of local tensile cracks at the coal–rock interface. Subsequently, we established the energy transfer model of the rock–rock–gas composite specimen in the process of dynamic destabilization in the engineering scale mining field and revealed the mechanism of nonlinear energy evolution and release of the coal–rock–gas composite, which has been less reported in previous studies. In this paper, we further clarified the occurrence and development mechanism of coal–rock–gas compound dynamic disasters in the engineering scale mining environment to guide the prevention and control of coal–rock–gas dynamic disasters in deep mines. [ABSTRACT FROM AUTHOR]

Background and Objectives: It has previously been shown that the International Fitness Scale (IFIS) is a reliable and valid instrument when used in numerous regions and subgroups, but it remains to be determined whether the IFIS is a reliable instrument for use with Chinese children and adolescents. If the reliability of the IFIS can be verified, populational surveillance and monitoring of physical fitness (PF) can easily be conducted. This study aimed to test the reliability of the IFIS when used with Chinese children and adolescents. Methods: The convenience sampling method was used to recruit study participants. In total, 974 school-aged children and adolescents between 11 and 17 years of age were recruited from three cities in Southeast China: Shanghai, Nanjing and Wuxi. The study participants self-reported demographic data, including age (in years) and sex (boy or girl). The participants completed the questionnaire twice within a two-week interval. Results: A response rate of 95.9% resulted in a sample of 934 participants (13.7 ± 1.5 years, 47.4% girls) with valid data. On average, the participants were 13.7 ± 1.5 years of age. The test–retest weighted kappa coefficients for overall fitness, cardiorespiratory fitness, muscle fitness, speed and agility and flexibility were 0.52 (Std. errs. = 0.02), 0.51 (Std. errs. = 0.02), 0.60 (Std. errs. = 0.02), 0.55 (Std. errs. = 0.02) and 0.55 (Std. errs. = 0.02), respectively. Conclusions: The International Fitness Scale was found to have moderate reliability in the assessment of (self-reported) physical fitness in Chinese children and adolescents. In the future, the validity of the IFIS should be urgently tested in Chinese subgroup populations. [ABSTRACT FROM AUTHOR]

The purpose of this paper, based on the amount of ultraviolet (UV) radiation in different areas of China, was to give the corresponding measures to prevent UV aging of asphalt. In this paper, based on the average annual amount of UV radiation in China in the past 30 years and the characteristics of UV aging of asphalt, the climatic zoning of UV radiation of asphalt in China was proposed. A variety of base asphalts and styrene–butadiene–styrene block copolymer (SBS) modified asphalts were selected to carry out a UV radiation test, and the relationship between UV radiation amount and viscosity, low-temperature performance, and the rheological properties of asphalt were studied. The equivalent aging indexes of asphalt during UV radiation were selected, the UV aging equation of asphalt was proposed, and the equivalent UV aging relationship among different UV climate zones was established. The prevention and control strategies of UV aging of asphalt among different zones were proposed, and the above theory was verified using a trial road. The main conclusions in the paper are presented: The climate zoning of asphalt UV radiation in China can be divided into three zones: zone I with an annual UV radiation less than or equal to 69.4 kW·h/m2 in the last 30 years; zone II with an annual UV radiation of 69.4~81.4 kW·h/m2 in the last 30 years; zone III with an annual UV radiation more than or equal to 81.4 kW·h/m2 in the last 30 years. The greater the amount of UV radiation, the greater the loss rate of penetration and ductility. For the same kind of asphalt, there is a relatively stable functional relationship between the loss rate and the amount of UV radiation. The results also show that UV radiation changes the proportion of viscous and elastic components in asphalt, showing that the proportion of viscous components decreases and the proportion of elastic components increases. The penetration loss rate and ductility loss rate of asphalt can be used as equivalent UV aging indexes of asphalt. Under the same outdoor UV irradiation time, for asphalt to achieve the same technical performance as zone I, the anti-UV ability of zone II needs to be improved by more than 5%, and that of zone III needs to be improved by more than 10%. Engineering practice has proved that the zoning established in this paper and the corresponding UV control measures are basically reasonable. [ABSTRACT FROM AUTHOR]

Lower Cambrian shale and lower Silurian shale are both typical of oil-prone kerogen and siliceous composition, but different in thermal maturities. Porosity differences were determined in marine shales between the two shales. Measurements were utilized including organic geochemistry, XRD, scanning electron microscopy (SEM) and N2 gas adsorption. Pore volume (PV) of lower Silurian shale was approximately 1.5 times higher than that of lower Cambrian shale, and pore surface area (PSA) of lower Silurian shale was almost 2.5 times higher than that of lower Cambrian shale. Lower Cambrian shale and lower Silurian shale possess similar materials, but distinctive thermal degrees. Evolution mechanisms of different types of pores, especially organic matter (OM)-hosted pores, may trigger this different pore features. Pores of rigid framework are the residue of primary interparticle pores during the burial history. Pores associated with clay flakes can be preserved well adjacent to rigid grains or secondary minerals acting as rigid frameworks or grain supporters. Dissolved pores in both lower Cambrian shale and lower Silurian shale barely contribute to the total porosity and mean little to the permeability. Both excessive OM content and over thermal maturity are detrimental to development of OM-hosted pores. Rigid particles, clay flakes, and OM commonly co-exist within shale matrix. Rigid grains act as supporters, clay flakes confine ample space, and OM first migrates into and provides secondary OM-hosted pores. In this condition, pores can be preserved owing to associating matrix with good mechanic and chemical stability. The significant differences of structural settings result into various hydrocarbon explosion efficiency and different pressure circumstance, which consequently leads to the different pore features between the two shales. For lower Cambrian shale, overpressure circumstance diminish if hydrocarbon expels outside of the shale system, and OM-hosted pores destroy through compaction. Sustaining overpressure and abundant residue hydrocarbon (migrated OM) make positive contributions to the pore properties, in terms of numbers, diameters and connectivity of the lower Silurian shale samples. [ABSTRACT FROM AUTHOR]