Spectrum distribution is a classical licensed spectrum accessing method in mobile communication networks. The licensed idle spectrum resources are authorized and distributed from spectrum owners to mobile users. However, the exponential growth of user capacity brings excessive load pressure on the traditional centralized network architecture. As lack of sufficient supervision and penalty measures, dishonest behaviors of spectrum owners and spectrum users will lead to the unfair status in the distribution process. As a result, the honest participants’ interest will be harmed. As an important supporting infrastructure of Internet of things technology, 6G cannot completely follow the existing spectrum distribution method. Towards 6G network spectrum distribution, an blockchain based licensed spectrum fair distribution method is proposed. A lightweight consensus mechanism named as proof of trust (PoT) is applied to reduce computational power consumption and consensus time overhead. We deploy the method on the Ethereum test chain, theoretical analysis and experimental results demonstrate the fairness, effectiveness and security of the method.

To explore the characteristics of the concentric eyewall of a typhoon during its formation and replacement processes, with Super Typhoon Muifa in 2011 as the example case, the Weather Research and Forecast (WRF) mode was used to carry out a numerical simulation to reproduce the entire formation and replacement processes of the concentric eyewall. The physical quantities such as the tangential wind speed, radar echo, radial wind speed, vertical wind speed, and potential vortex were diagnosed and analyzed. The results of the analysis show that the outward expansion of the isovelocity in the lower troposphere was the early signal of the formation of the outer eyewall. After the outer eyewall formed, there was a center of second-highest tangential wind speed in the corresponding area. The second-highest wind speed increased as the strength of the outer eyewall increased, and the position of the second-highest wind speed center was retracted with the retraction of the outer eyewall. The tangential wind speed of the moat area was smaller than that corresponding to the concentric eyewall and this feature gradually disappeared with the increase of the height. The echo in the moat area was weak, and this characteristic was particularly evident when the moat area was relatively wide and the outer eyewall was relatively strong. With the formation and development of the outer eyewall, the intensity of the inflow in the boundary layer corresponding to the inner eyewall was reduced, the intensity of the outflow in the upper layers declined, and the intensities of the inflow and outflow corresponding to the outer eyewall were enhanced. After the second outer eyewall matured, there was a significant inflow in the upper layer of the moat area. Once the outer eyewall formed, a large amount of hydrometeors appeared in the corresponding area, and there was a strong ascending motion inside that area. The strength of the ascending motion and the content of hydrometeors increased as the outer eyewall increased. When the moat area was relatively wide, the divergent airflow generated by the developed outer eyewall in the upper layer would produce a significant descending motion in the moat area.

Cabbage (Brassica oleracea L. var. capitata) plays a very important role in the annual national vegetable supply and export trade. In recent years, the cadmium content of agricultural soils has increased. As a result, cabbage yields and quality have declined significantly. Studies have shown that selenium can counteract the harmful effects of cadmium on plants and can alleviate the stress caused by cadmium during the growth of plants. However, the mechanism of exogenous selenium application in the alleviation of cadmium stress in cabbage seedlings has not been thoroughly investigated. In this study, exogenous selenium (10μMol/L) was applied under cadmium (25μMol/L) stress and the physiological mechanisms such as biomass, photosynthetic pigment, leaf stomata parameters, selenium and cadmium content, chloroplast ultrastructure, active oxygen accumulation, leaf membrane esterification and antioxidant enzyme activity were determined. The protective mechanism of exogenous selenium on cabbage seedlings under cadmium stress was investigated. The re-sults showed that exogenous application of selenium could effectively alleviate the decrease in growth, photosynthetic pigment and gas exchange characteristics of cabbage seedlings under cadmium stress, im-prove cabbage root vitality, reduce root leaf cadmium content and alleviate cadmium stress-induced damage. Ultrastructural observation showed that cadmium stress caused the disruption of the internal structure of chloroplasts of cabbage leaves, while exogenous selenium treatment alleviated the chloroplast damage to some extent, improved the stability of the inner capsule membrane and alleviated the cadmium stress-induced damage to photosynthetic organs. Cadmium stress also caused oxidative damage and ex-cessive accumulation of ROS in the leaves of cabbage seedlings as evidenced by significant accumulation of O2-, H2O2, MDA and electrolyte leakage. On the other hand, after exogenous selenium treatment, cadmium stress- induced oxidative damage could be reduced by up-regulating the activities of antioxidant enzymes SOD, POD and APX. At the same time, cadmium stress significantly increased GSH levels, and exogenous selenium treatment further increased GSH levels, thereby increasing the tolerance of cabbage to cadmium stress. In conclusion, by protecting the photosynthetic system, eliminating excessive accumulation of reactive oxygen species in cadmium-stressed cabbage seedlings, alleviating oxidative stress and reducing cadmium levels in the plant, exogenous selenium can further improve cadmium tolerance in cabbage seedlings.

Abstract: Kiwifruit, a perennial horticultural crop known for its nutritional value, faces significant challenges due to biotic and abiotic stresses, affecting its yield and quality. Leucine-rich repeat receptor-like proteins (LRR-RLPs), a major group of receptor-like proteins in plants, have diverse functions in plant physiology, including growth, development, signal transduction, and stress responses. Despite their importance, the specific roles of kiwifruit LRR-RLPs in response to biotic and abiotic stresses remain poorly understood. In this study, we investigated the expression patterns of kiwifruit LRR-RLPs under various stress conditions, including pathogen stress, heat stress, waterlogging stress, and copper stress. Through genome and transcriptome analyses, we identified a total of 101, 164, and 105 LRR-RLPs in Actinidia Chinensis 'Hongyang', Actinidia eriantha 'Huate', and Actinidia chinensis 'Red5' kiwifruit, respectively, classified into 9 subgroups based on phylogenetic relationships. Synteny analysis revealed that the expansion of kiwifruit LRR-RLPs was primarily attributed to segmental duplication events. Using RNA-seq data from pathogen-infected kiwifruits, we identified specific LRR-RLP genes potentially involved in different stages of pathogen infection. Additionally, we observed the potential involvement of kiwifruit LRR-RLPs in abiotic stress responses, with upstream transcription factors possibly regulating their expression. Furthermore, protein interaction network analysis unveiled the participation of kiwifruit LRR-RLP genes in the regulatory network of abiotic stress responses. These findings highlight the crucial roles of LRR-RLPs in mediating both biotic and abiotic stress responses in kiwifruit, offering valuable insights for the breeding of stress-resistant kiwifruit varieties.