Search

【Objective】 Organic materials including crop straws, organic fertilizers, biochar have been widely used in agriculture as an agent to improve soil structure and fertility, but how, and to what extent, their efficacy varies with soil texture and environmental factors remains elusive. This review aims to fill this knowledge gap. 【Method】 Our review is based on papers published over the past decades, which reported the effects of different organic material amendments on structure and fertility of soils with various textures in different climatic regions. 【Result】 In low-temperature and arid regions, application of organic fertilizer and polyacrylamide works better for improving soil structure, while in regions characterized by changeable climate and high temperature and humidity, incorporating straw to soils has the edge to improve physical properties of the soils. Amending coarse-textured soils with biochar improves soil structure more than other amendments, while woody peat works better for fine-textured soils. We also review the latest development in non-destructive imaging technologies inducing x-ray computed tomography and digital image processing which have been increasingly used to quantify soil structural alteration due to natural and management practice changes. 【Conclusion】 Soils are hierarchically structured and there is no universal rule to select an amending material to improve their structure. Its selection should consider the inherent physical and chemical properties of the soils to be amended and the climate region.

The High Energy Photon Source (HEPS) is expected to produce a substantial volume of data, lead to immense data I/O pressure during computing. Inefficient data I/O can significantly impact computing performance. To address this challenge, firstly, we have developed a data I/O framework for HEPS. This framework consists of three layers: data channel layer, distributed memory management layer, and I/O interface layer. It mask the underlying data differences in formats and sources, while implementing efficient I/O methods. Additionally, it supports both stream computing and batch computing. Secondly, we have designed a data processing pipeline scheme aimed at reducing I/O latency and optimizing I/O bandwidth utilization during the processing of high-throughput data. This involves breaking down the computing task into several stages, including data loading, data pre-processing, data processing, and data writing, which are executed asynchronously and in parallel. Finally, we introduce the design of stream data I/O process. The primary objective of stream data I/O is to enable real-time online processing of raw data, avoiding I/O bottlenecks caused by disk storage. This approach ensures the stability of data transmission and integrates distributed memory management to guarantee data integrity in memory.

Objective:To investigate the imaging characteristics of thymoma and mediastinal lymphoma using spectral CT and evaluate whether the quantitative information can improve the differential diagnosis of these diseases.Methods:This retrospective study was approved by the institutional review board, and written informed consent was obtained from all patients. Overall, 39 patients with mediastinal tumors (24 thymomas and 15 mediastinal lymphomas) were examined with CT spectral imaging during the arterial phase (AP) and venous phase (VP). Iodine concentrations were derived from iodine-based material-decomposition CT images and normalized to the iodine concentration in the aorta. The difference in normalized iodine concentrations (NICs), HU curve slop(λHU), and the differences between AP and VP for CT values of lesions in 70 Kev were calculated. The two-sample t-test was performed to compare quantitative parameters, and non-quantitative parameters were compared with the Chi-square test (Fisher exact). Receiver operating characteristic (ROC) curves were generated to help establish threshold values for the parameters required for the significant differentiation of thymomas from mediastinal lymphomas. Two readers qualitatively assessed the lesion types according to the imaging features. The sensitivity and specificity of the qualitative and quantitative studies were compared.Results:NICs during the VP and λHU during the AP in patients with mediastinal lymphomas differed significantly from those in patients with thymomas. The mean NICs during the VP were 0.28 ± 0.08  mg ml-1 (±standard deviation) vs 0.49 ± 0.15  mg ml-1, respectively. The λHU during the AP was 0.69 ± 0.17 vs 1.26 ± 0.74, respectively. The NICs during the VP and λHU during the AP had high sensitivity and specificity in differentiating mediastinal lymphomas from thymomas. The tumor location, margin, necrosis, presence of swollen mediastinal lymph nodes, relationship with adjacent vessels, and enhancement pattern differed significantly between the groups (p < 0.05). The combination of NICs and λHU had higher sensitivity and specificity than did those of conventional qualitative CT image analysis during the combined phases.Conclusion:CT spectral imaging has promising potential for the diagnostic differentiation of mediastinal lymphomas and thymomas. The iodine content and λHU could be valuable parameters for differentiating thymomas and mediastinal lymphomas.Advances in knowledge:The iodine content and λHU, provided by spectral CT, could be used as new parameters to distinguish mediastinal lymphomas from thymomas.