One of the most significant environmental factors affecting plant growth, development and productivity is salt stress. The damage caused by salt to plants mainly includes ionic, osmotic and secondary stresses, while the plants adapt to salt stress through multiple biochemical and molecular pathways. Tomato (Solanum lycopersicum L.) is one of the most widely cultivated vegetable crops and a model dicot plant. It is moderately sensitive to salinity throughout the period of growth and development. Biotechnological efforts to improve tomato salt tolerance hinge on a synthesized understanding of the mechanisms underlying salinity tolerance. This review provides a comprehensive review of major advances on the mechanisms controlling salt tolerance of tomato in terms of sensing and signaling, adaptive responses, and epigenetic regulation. Additionally, we discussed the potential application of these mechanisms in improving salt tolerance of tomato, including genetic engineering, marker-assisted selection, and eco-sustainable approaches.

The SiC particles (SiCp, mass fraction 30 %) reinforced with the Al-Si-Cu-Mg matrix composite have been prepared using one-way press method, sintering, and hot extrusion. The composite was subjected to solid solution treatment at temperatures of 470 °C, 485 °C, 500 °C, 515 °C, and 530 °C for 4 h. The sample was then subjected to ageing treatment at temperatures of 160 °C and 180 °C during different times after solid solution treatment at 515 °C for 4 h. The microstructure and mechanical properties of the SiCp/Al-Si-Cu-Mg matrix composite under the different ageing and solid solution treatments were tested using SEM and TEM microhardness analysis. The results show that the white granulated metallic compounds of the SiCp/Al-Si-Cu-Mg composite materials, which are formed in the sintering process of composite materials, dissolve back after the solid solution treatment at different temperatures. The higher the solid solution temperature, the more metallic compounds dissolve back. The microhardness of the composites reached maximum after solution treatment at 515 °C for 4 h. Following the ageing treatment and with the prolongation of ageing time, the hardness of the composite material reached "double peak" phenomenon. With the increase in ageing temperature, the hardening speed of the composite material also increased, but at the same time, the hardening ability had reduced. After the ageing treatment, the second phases of the composite are discoid Al 5 Cu 6 Mg 2 .

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SiCp/A390 (SiC particle reinforced Al matrix) composites before and after SiC particles surface modification were manufactured respectively by powder metallurgy, and the mass fraction of SiCp is 20%. The surface morphology of SiCp and the interface morphology of SiC/Al and SiC/Si of composites were characterized by TEM. The chemical state of interface material of SiCp/A390 composites was tested by XPS. The effect of surface modification of SiCp on interface structure of composites and thermodynamic principle of mechanism of interface formation of SiCp/A390 were researched. The results show that SiCp morphology was changed though surface optimization treatment, the dense SiO 2 oxide layer on the surface of SiCp was formed when SiC particles were roasted at 1000℃, which thickness membrane is about 50 nm. Before SiC particles surface modification, the interface of SiC/Al of composites is clear, clean interface, and discovered a small amount of amorphous layer interface of SiC/Al. While, after SiC optimization, the interface of SiC/Al of composites is an amorphous layer between two phases, and there is no Al 4 C 3 in SiCp/A390 composites. Surface modification treatment of SiCp can increase chemical reaction degree of the interface of composites, and effectively improve the interface bonding of SiC and Al.

Background Hemodialysis patients are prone to gastrointestinal bleeding, and Mallory-Weiss syndrome (MWS) is one of the causes. Mallory-Weiss syndrome is often induced by severe vomiting, manifests as upper gastrointestinal bleeding, and is self-limited with a good prognosis. However, mild vomiting in hemodialysis patients can lead to the occurrence of MWS, and the mild early symptoms are easy to misdiagnose, leading to the aggravation of the disease. Case presentation In this paper, we report four hemodialysis patients with MWS. All patients displayed symptoms of upper gastrointestinal bleeding. The diagnosis of MWS was confirmed by gastroscopy. One patient had a history of severe vomiting; however, the other three reported histories of mild vomiting. Three patients received the conservative hemostasis treatment, and the gastrointestinal bleeding stopped. One patient underwent the gastroscopic and interventional hemostasis treatments. The conditions of three of the patients improved. Unfortunately, one of the patients died due to the cardia insufficiency. Conclusions We think that the mild symptoms of MWS are easily covered up by other symptoms. This may lead to delays in diagnosis and treatment. For patients with severe symptoms, gastroscopic hemostasis is still the first choice, and interventional hemostasis can also be considered. For patients with mild symptoms, drug hemostasis is the first consideration.