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While many studies have examined the role of biochar in carbon (C) accrual in short-term scale, few have explored the decadal scale influences of biochar on non-biochar C, e.g., native soil organic C (SOC) and added substrate. To address this knowledge gap, soils were collected from decade-old biochar field trials located in the United Kingdom (Cambisol) and China (Fluvisol), with each site having had three application rates (25–30, 50–60 and 75–100 Mg ha−1) of biochar plus an unamended Control, applied once in 2009. We assessed physicochemical and microbial properties associated with sucrose (representing the rhizodeposits) mineralization and the priming effect (PE) on native SOC. Here, we showed both soils amended with biochar at the middle application rate (50 Mg ha−1 biochar in Cambisol and 60 Mg ha−1 biochar in Fluvisol) resulted in greater substrate mineralization. The enhanced accessibility and availability of sucrose to microorganisms, particularly fast-growing bacterial genera like Arenimonas, Spingomonas, and Paenibacillus (r-strategists belonging to the Proteobacteria and Firmicutes phyla, respectively), can be attributed to the improved physicochemical properties of the soil, including pH, porosity, and pore connectivity, as revealed by synchrotron-based micro-CT. Random forest analysis also confirmed the contribution of the microbial diversity and physical properties such as porosity on sucrose mineralization. Biochar at the middle application rate, however, resulted in the lowest PE (0.3 and 0.4 mg of CO2-C g soil−1 in Cambisol and Fluvisol, respectively) after 53 days of incubation. This result might be associated with the fact that the biochar promoted large aggregates formation, which enclosed native SOC in soil macro-aggregates (2–0.25 mm). Our study revealed a diverging pattern between substrate mineralization and SOC priming linked to the biochar application rate. This suggests distinct mechanisms, biophysical and physicochemical, driving the mineralization of non-biochar carbon in a field where biochar was applied a decade before. Highlights: The application of biochar at a moderate rate (50–60 Mg ha−1) resulted in increased labile C mineralization and decreased priming of native SOC. Biochar amendments led to the reconfiguration of physicochemical properties, including pH, porosity, and the formation of aggregates. Modified microbial community structure towards more r-strategists caused greater sucrose mineralization. Biochar incorporation rate governed the C dynamics via (biophysical vs physicochemical mechanisms) in long-term biochar amended fields. [ABSTRACT FROM AUTHOR]

The use of radiotherapy in tumor treatment has become increasingly prominent and has emerged as one of the main tools for treating malignant tumors. Current radiation therapy for glioma employs 125I seeds for brachytherapy, which cannot be combined with radiotherapy and chemotherapy. To address this limitation, this paper proposes a dual-microcavity capsule structure that integrates radiotherapy and chemotherapy. The Monte Carlo simulation method is used to simulate the structure of the dual-microcavity capsule with a 125I liquid radioactive source. Based on the simulation results, two kinds of dual-microcavity capsule structures are optimized, and the optimized dual-microcavity capsule structure is obtained. Finally, the dosimetric parameters of the two optimized dual-microcavity capsule structures are analyzed and compared with those of other 125I seeds. The optimization tests show that the improved dual-capsule dual-microcavity structure is more effective than the single-capsule dual-microcavity structure. At an activity of 5 mCi, the average absorbed dose rate is 71.2 cGy/h in the center of the optimized dual-capsule dual-microcavity structure and 45.8 cGy/h in the center of the optimized single-capsule dual-microcavity structure. Although the radial dose function and anisotropy function exhibite variations from the data of other 125I seeds, they are generally similar. The absorbed dose rate decreases exponentially with increasing distance from the center of the capsule, which can reduce the damage to the surrounding tissues and organs while increasing the dose. The capsule structure has a better irradiation effect than conventional 125I seeds and can accomplish long-term, stable, low-dose continuous irradiation to form local high-dose radiation therapy for glioma. • Development of a novel dual-microcavity capsule structure for integrated radiotherapy and chemotherapy of glioma. • Optimize capsule structure and achieve high dose rates in the tumor center using Monte Carlo simulation. • Orthogonal tests were performed to optimize the capsule design parameters. • Improved dual-capsule dual-microcavity structure shows better efficacy than single-capsule dual-microcavity structure. [ABSTRACT FROM AUTHOR]

Optimizing tillage management is one way to reduce the risk of soil compaction due to traffic load in Northeast China. In this study, we aimed to examine the responses of precompression stress (σ pc), compression index (C c), pore morphology (>30 µm), air-filled porosity (ε a60), air permeability at matric potential of − 60 hPa (k a60) and saturated hydraulic conductivity (K s) to harvest traffic on soil from two contrasting tillage practices using a 10-yr old field experiment. After the crop was harvested with a combine harvester, undistributed soil cores were collected in the 0–10 and 10–20 cm layers from non-traffic and traffic zones of no-tillage (NT) and moldboard plough (MP) plots. In the non-traffic zone, the MP management showed greater total porosity (ε total), ε a60 and macroporosity (ε X-ray) than the NT. There were no differences in pore connectivity, mean pore size and k a60 of the 0–10 cm layer and in K s of the 0–20 cm layer between the two tillage practices, however, more biopores were observed under NT. Harvest traffic showed no significant effects on NT soil. In the MP plots, the ε total , ε X-ray , and pore connectivity, were decreased and pores larger than 0.15 mm were preferentially compacted. As a result of traffic, MP soil displayed lower k a60 in the 0–20 cm layer and lower ε X-ray and connectivity in the 10–20 cm layer. In the NT management, the pore system had greater water and air conduction efficiencies and stable properties. Thus, compared to MP, NT can mitigate the negative effects of harvest compaction on soil in Northeast China. • Compared with MP, NT yields lower porosity and permeability before traffic pass. • After traffic pass, NT shows more stable soil pore system and better permeability. • NT mitigates the negative effects of harvest traffic on soil pores and permeability. [ABSTRACT FROM AUTHOR]

Soil structure influences the soil hydraulic properties, aeration and resistance to root penetration. Many indicators can be used to investigate the changes of soil structure, but using a single indicator or method has limitations. This study evaluates the effects of 15-years tillage management on soil structure with soil bulk density (BD) , penetrometer resistance (PR), soil water retention curve (SWRC), least limiting water range (LLWR) and X-ray computed tomography (CT). The treatments include no-tillage (NT), rotary tillage (RT), and mouldboard plough (MP). Soil bulk density of the 0–30 cm soil profile was measured after the establishment of tillage treatments for 7, 9, 12 and 14-years. The values of PR , SWRC, LLWR, and 3-D pore geometry of the 5–10 and 15–20 cm layers were determined in the 15th year of the experiment. The greater BD in the 0–5 cm layer of NT was not observed after 9 years, but an increased BD in the 5–20 cm layer was found in most years. Tillage had no effect on PR in wet soil. When soil had dried, the NT treatment had a greater PR and it was the lower limiting factor of LLWR, ultimately leading to a narrower LLWR of NT. Both NT and RT showed lower proportions of structural but higher textural pores. The macroporosity (> 50 µm) from X-ray CT was greater than that estimated from SWRC of the 15–20 cm layer. The characteristics of pore morphology were similar under three tillage treatments. Therefore, NT resulted in a narrower LLWR due to the denser soil layer, yet similar macropores may alleviate the negative impacts on crop growth caused by lower LLWR. It was suggested that using LLWR and characteristics of macropores from X-ray CT at the same time is a suitable way to assess soil structure under various tillage practices. • After 15-years no-tillage, the physical quality is poor in 5–20 cm layer reflected by greater BD, PR, and lower LLWR. • Similar properties of macropore weak the usefulness of LLWR for assessing soil structure under no tillage treatment. • Combining LLWR with macropores from X-ray CT is a suitable way to assess soil structure under various tillage practices. [ABSTRACT FROM AUTHOR]