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As a common bulking agent and stabilizer for residents, aluminum-containing food additives have a comprehensive application scenario. However, it is noteworthy that the abuse of aluminum-containing food additives may cause a potential health risk to the public. Taking aluminum-containing food additives as the research object, the paper systematically discusses the basic characteristics of aluminum-containing food additives, detection technology of aluminum-containing food additives, and monitoring of food aluminum content, and summarizes the current problems for each part.

Based on weather radar data, precipitation data from densified rainfall stations, hydrological data at Wucha hydrological station in Qijiang Catchment and ERA5 reanalysis data, we have conducted the analysis of a record-breaking flood event occurred in Qijiang Catchment from June 19 to 22 in 2020 including the spatial-temporal distribution of precipitation, the circulation background, the water vapor sources and the evolutional characteristics of mesoscale convective systems (MCSs). The results indicate that (1) this event is a persistent severe precipitation event with concentrated range and characterized by obvious periodic and diurnal variation. It can be divided into three stages. Severe precipitation mainly occurs at night. (2) Persistent heavy rainfall occurs under the circulation pattern of cold air guided by east-moving cold low pressure in the Ural Mountains moving southward to the northeast of Sichuan Basin, low trough in the mid-latitude maintaining for a long time in the eastern Sichuan-Chongqing-Guizhou area and the Western Pacific subtropical high being stable. (3) Low-level warm and moist southwest jet further increases the atmospheric stratification instability between northern Guizhou and southern Chongqing, and it conveys water vapor from South China Sea and Bengal Bay to Qijiang River Basin, providing abundant water vapor for the generation and persistence of heavy rainfall. (4) The occurrence and development of MCSs at the three severe precipitation stages show different features. At the first stage, MCSs in coherence with the strong radar echoes are situated in roughly north-south direction, moving eastward to affect the Qijiang Catchment, and the duration of heavy rainfall is therefore relatively short. Next, the MCSs present southwest-northeast direction, affecting Qijiang Catchment for a longer time, but the echo intensity is weak. At last stage, the MCSs present massive. And they are linearly distributed in the northwest-southeast direction when they mature, exhibiting "train effect", which affects Qijiang Catchment longest and cause the greater precipitation intensity.

Lung cancer is a malignant tumor with high incidence and mortality in the world, which seriously threatens people’s safety and health. Early diagnosis of lung cancer is the key part in the process of prevention and treatment of lung cancer. It can improve the survival of patients with lung cancer. Exosomes are closely related to the invasion and metastasis process of tumor, it plays an important role in the development of lung cancer. Biomarkers based on exosomes have become a powerful diagnostic tool of lung cancer. Exosomes are lipid bilayer vesicles with uniform size and diameter of 30 nm-200 nm secreted by cells. Exosomes contain different types of nucleic acids and proteins. These nucleic acids and proteins are derived from their parent cells (including parent cancer cells), which have a wide range of physiological functions, including immune regulation, intercellular communication and other physiological activities. Biomacromolecules in exosomes, such as single-stranded RNA, long noncoding RNA, microRNA, protein and lipids, which can provide valuable genetic information for early clinical diagnosis of lung cancer. This review described the origin, structural characteristics, extraction methods, biological characteristics of exosomes and the relationships of exosomes in the early diagnosis of lung cancer.

Due to the function of communication and continuous monitoring,the low-earth orbit satellites are widely used in the aerospace field.However,there is no special authentication protocol in the existing satellite communication system.In order to solve this problem,a lightweight authentication protocol which considering the switch of communication path in the authentication process was designed for the low-earth orbit satellites,and the proposed protocol was verified by simulation and compared with the 3GPP AKA protocol.The simulation results show that the protocol has a 20% higher efficiency than 3GPP AKA protocol,and the spend of group key agreement protocol is about 300 ms.

Currently, limited studies focused on the variations in submarine fresh groundwater discharge rates, seawater recirculation rates, and their respective proportions with tidal level change in sandy intertidal zones. This study conducted in-situ dynamic monitoring of the salinity at the groundwater seepage face in a sandy tidal flat in Xiamen Bay. Using variable-density flow numerical model, the dynamic groundwater salinity in the intertidal zone was simulated to calculate the submarine fresh groundwater discharge in the intertidal zone. The results show that groundwater salinity at different locations in the intertidal zone exhibits varying patterns with the tides. The submarine groundwater discharge at a typical profile was estimated to be 17.47 m3/(m·d), in which the submarine fresh groundwater discharge was calculated to be 3.19 m3/(m·d), accounting for 18.26% of the total submarine groundwater discharge. In contrast, recirculated submarine groundwater discharge was estimated to be 14.28 m3/(m·d), constituting 81.74% of the total submarine groundwater discharge and thus playing a dominant role. Under the influence of tides, seawater infiltration and submarine groundwater discharge are alternate. The alternation during ebb tide occurs slightly earlier than the slack water level, while during flood tide, it occurs slightly later. The peak moment of seawater infiltration rate and submarine groundwater discharge rate precede the tidal peaks at high and low tides, respectively. Throughout the tidal cycle (from high tide to the next high tide), the proportion of submarine fresh groundwater discharge gradually increases. The variation in groundwater salinity in the intertidal zone can represent the changes in submarine fresh groundwater discharge. The proportion of submarine fresh groundwater discharge in the total submarine groundwater discharge is relatively high in this typical profile than that in the previous studies. It indicates the presence of a substantial amount of submarine fresh groundwater discharge in the intertidal zone. Through sensitivity analysis, it reveals that inland hydraulic head has significant influences on submarine fresh groundwater discharge and spatial distribution of salinity. This study can provide scientific information for the development and utilization of coastal groundwater and the management of coastal environments.

Seawater-recharged geothermal systems are characterized by abundant recharge, low temperature and salinization. Ascertaining the circulation recharge conditions and genetic mechanisms of geothermal water in coastal areas of southeast China is of important significance in the rational exploration, utilization and protection of geothermal resources in these areas. In this study, 14 samples of geothermal water, groundwater and seawater are collected from the Yantian geothermal field near Guanqiao Town in Fujian Province, China and the hydrochemical and isotopic characteristics are analyzed. The circulation recharge of the geothermal water and the genetic mechanisms of the geothermal resources in the geothermal field are revealed using geothermometers. The results show that hydrochemical type of the geothermal water in the Yantian geothermal field is of Cl—Na type, which is similar to that of the seawater. Total dissolved solids of geothermal water samples H01 and H02 are 2 610 mg/L and 3 090 mg/L, respectively. By contrast, the groundwater in the geothermal field is dominated by the HCO3—Na type, and the groundwater samples have TDS of less than 400 mg/L. Moreover, the geothermal water is rich in Br−, which is not detected in the groundwater. These results indicate that modern seawater or ancient seawater in marine sedimentary layers is a recharge source of the geothermal water. As shown by the results of H01 and H02 calculated using the Cl− mixing model, geothermal water samples H01 and H02 have seawater mixing ratios of 9.13% and 10.76%, respectively, and H01 is mixed with more groundwater after being exposed to Quaternary sediments. The comprehensive analyses show that the geothermal water in the Yantian geothermal field is primarily recharged by seawater and its chemical composition is significantly affected by seawater mixing. Furthermore, the comprehensive analyses also suggest that the deep geothermal water is mixed with groundwater or seawater twice or more times as it rises upward, thus forming shallow geothermal reservoirs with a temperature of 89 °C to 121 °C, as estimated by using the SiO2 geothermometer and the multi-mineral equilibrium method.

To learn about the diversity of microorganisms in different flavor sufu from different origins in China. Based on high throughput sequencing (HTS), the microbial diversity differences and chemical properties of 16 sufu samples from different origins in China were analyzed in this study. The results of bacterial diversity showed that the most abundant bacteria in sufu were Lactobacillus sp and Bacillus sp, which also represented the dominant bacterial communities in different stages of sufu fermentation. The results of fungal diversity showed that sufu contained a large number of Aspergillus, Actinmucor sp. and other hydrolase producing bacteria. The results of chemical composition determination showed that different origins had certain influence on the chemical composition of sufu. The soluble protein content and amino nitrogen content in curd showed positive correlation with the distribution of Bacillus in the samples. The results of principal coordinate analysis showed that the fungal consortium structure in sufu samples from 16 origins had certain clustering relationship with regions, specifically the fungi from eastern China (ZJ2, ZJ4, ZJ5, ZJ6, SH9, AH11 and JX12) could be grouped together, which stated that the fungal consortium of sufu may be influenced by geographical factors. This study deepened the understanding of microbial community diversity in sufu and would provide theoretical support for the quality improvement of traditional fermented condiments.

A biotransformation system (LSBT) consisting of Lactococcus lactis and Streptococcus lactis was used to eliminate the yeasty odor of eight yeast extracts with different characteristics (FG10, FM88, FM31, KU012, FIG12LS, F58, FIG03 and KA02) with a focus on flavor substances and amino acids. Meanwhile, the applicability and universality of LSBT were evaluated. All yeast extracts had no longer any yeasty flavor after being treated with LSBT, and FG10 and FM88 were provided with a fermented sauce flavor. Producing no indole was found to be one of the key factors for the success of LSBT. At the same time, the lactic acid content of the transformed yeast extract should not be less than 10.00 g/L. The difference of raw materials played an important role in the LSBT. In particular, the deficiency of aspartic acid and excessive accumulation of threonine in raw materials were likely reasons for the unsuccessful conversion of LSBT. Overall, LSBT is applicable to most yeast extracts, but other microbial combination techniques or fermentation conditions need to be explored for specific yeast extracts such as F58, FIG03 and KA02.