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Salt patches (SPs) with surface salt accumulation pose a serious threat to agriculture in coastal saline lands. However, the migration and distribution of soil water and salt in SPs remain unclear due to complex water–salt transport dynamics. In this study, we focused on typical SPs in the Yellow River Delta region and selected center site (Site 1), transition site (Site 2), edge site (Site 3), and outer site (Site 4) with varying levels of salinization. Field sampling and the HYDRUS-1D model were employed to investigate the migration process and distribution of soil water and salt in SPs, as well as the influencing factors. The results indicated significantly higher salt contents in the central sites (Site 1 and Site 2) compared to the edge sites (Site 3 and Site 4), while no significant differences were observed in soil water content. The bottom soil exhibited greater stability in terms of water and salt content compared to the surface soil. Additionally, soil water content increased with soil depth, whereas salt content decreased from Site 1 to Site 3. Interestingly, Site 4 exhibited the opposite salt distribution pattern in the whole soil depth. We observed that SPs displayed a salt aggregation structure radiating from the center to the periphery, gradually weakening in intensity. Our correlation analysis indicated that the formation of SPs may be influenced by soil particle size distribution, precipitation, and evaporation. Specifically, fine soil structure can impede the upward transport of highly mineralized groundwater, while precipitation and evaporation directly affect the leaching and upward movement of surface soil salt, resulting in uneven salt distribution in the field and the formation of SPs. These findings provide valuable theoretical and technical insights for the prevention and improvement of saline farmlands in the Yellow River Delta.

Enhanced atmospheric nitrogen deposition can greatly influence the soil nitrogen content and soil microorganisms in terrestrial ecosystems. However, there is a lack of knowledge about the response of soil microbes to changes in soil nitrogen, particularly in desert ecosystems. To address this, we used long-term artificial nitrogen addition to simulate atmospheric nitrogen deposition in a desert ecosystem in Ningxia, China. We adopted a high-throughput sequencing method (16S rRNA and ITS) to explore the effects of different amounts of atmospheric nitrogen deposition on soil microbial diversity and community structure. Six years of nitrogen addition (6 g N m−2 y−1) significantly increased the soil organic carbon content and the total soil nitrogen content (p 0.05). Further analysis revealed that nitrogen addition substantially reduced the number of positive correlations between soil microbial species and the number of core microbial species. Our results suggest that for desert ecosystems, at present, atmospheric nitrogen deposition may increase soil nitrogen use by some vegetation but it does not alleviate the competition for soil nitrogen between soil microbes and vegetation. Moreover, although enhanced atmospheric nitrogen deposition did not significantly change the soil microbial community structure, it may negatively affect the interactions among soil microbial species. This would hinder soil microbial adaptation to the changing environment and the development of desert ecosystems.

The responses of soil respiration to environmental conditions have been studied extensively in various ecosystems. However, little is known about the impacts of temperature and moisture on soils respiration under biological soil crusts. In this study, CO2 efflux from biologically-crusted soils was measured continuously with an automated chamber system in Ningxia, northwest China, from June to October 2012. The highest soil respiration was observed in lichen-crusted soil (0.93 ± 0.43 µmol m-2 s-1) and the lowest values in algae-crusted soil (0.73 ± 0.31 µmol m-2 s-1). Over the diurnal scale, soil respiration was highest in the morning whereas soil temperature was highest in the midday, which resulted in diurnal hysteresis between the two variables. In addition, the lag time between soil respiration and soil temperature was negatively correlated with the soil volumetric water content and was reduced as soil water content increased. Over the seasonal scale, daily mean nighttime soil respiration was positively correlated with soil temperature when moisture exceeded 0.075 and 0.085 m3 m-3 in lichen- and moss-crusted soil, respectively. However, moisture did not affect on soil respiration in algae-crusted soil during the study period. Daily mean nighttime soil respiration normalized by soil temperature increased with water content in lichen- and moss-crusted soil. Our results indicated that different types of biological soil crusts could affect response of soil respiration to environmental factors. There is a need to consider the spatial distribution of different types of biological soil crusts and their relative contributions to the total C budgets at the ecosystem or landscape level.

The investigation of the response mechanisms of Cyperus esculentus to water and salt stresses is crucial for the enhancement of the productivity of saline soils. Previous studies have indicated that plant hormones, antioxidant systems, and osmoregulation may contribute to the stabilization of yield. However, the contributions and interactions of these mechanisms remain poorly understood under combined water and salt stress in natural environments. A dual-factor (salt and water) orthogonal test was used to investigate the growth and biochemical responses of C. esculentus, under combined salt and water stress in a field experiment conducted on a typical saline area in northern China. The findings reveal that C. esculentus adjusted its biomass allocation strategies and activated hormone responses, antioxidant system, and osmoregulation mechanisms to maintain stable yield. Due to the negative synergism when salt and water stress coexist, the homogeneous limitations of both are weakened. Thus, the key to maintaining yields under combined water and salt stress may depend on indirectly enhancing tolerance to oxidative damage through abscisic acid, rather than focusing on accumulating low molecular weight osmoregulants and antioxidant enzymes to directly alleviate homogeneous limitations. Also, under combined salt and water stress, insufficient irrigation may have a greater impact on morphological characteristics than high salinity. The above results contribute to a deeper understanding of the process of adapting C. esculentus to combined salt and water stress. [ABSTRACT FROM AUTHOR]

Mitochondrial dysfunction is the common pathological basis of myocardial ischemia/reperfusion (I/R) injury, which induces an intriguing study on mitochondrial-targeting compounds to treat mitochondrial dysfunction related diseases. Herein, a novel mitochondrial targeting compound Tan-TPP was synthesized based on tanshinone IIA (Tan), an active constituent of Chinese medicine salvia miltiorrhiza. We employed TMT labeled quantitative mass spectrometry, bioinformatics analysis, gene knockdown and overexpression assays to explore the regulation mechanism of Tan-TPP on attenuating myocardial I/R injury. Intriguingly, Tan-TPP could accumulate in mitochondria and significantly attenuate myocardial H/R injury at cellular level and I/R injury in vivo. It can regulate the expression of mitochondrial protein GUF1, thereby reducing SDHA expression level to attenuate oxidative injury. Consequently, this study expands our understanding on the mechanism of mitochondrial-targeting molecules to attenuate myocardial I/R injury, and it also provides a new strategy to improve the efficacy of Chinese medicine.

With the rapid development of ubiquitous data collection and data analysis, data privacy in a recommended system is facing more and more challenges. Differential privacy technology can provide strict privacy protection while reducing the risk of privacy leakage, but it also introduces unwanted noise, which makes the performance of the recommender system worsen. Among different users, the degree of their sensitivity to privacy is usually different. Thus, through considering the impact of users’ personalized requirements, the collaborative filtering algorithm can be designed to reduce the amount of unwanted noise. Taking the above assertions into account, we propose a collaborative filtering algorithm based on personalized privacy protection. First, it locally classifies ratings by privacy sensitivity on the user side, then utilizes the random flip mechanism to protect the privacy-sensitive ratings. Then, after the server catches the perturbed rating data, we reconstruct the joint item-item distribution through the Bayesian estimation method. Experimental results show that our proposed algorithm can significantly improve the recommendation performance of recommendation systems while protecting users’ privacy.

RING finger protein 135 has an important role in the occurrence of many cancers; however its regulation and function of RNF135 in hepatocellular carcinoma remains unknown. The promoter methylation status and mRNA expression of RNF135 was evaluated by methylation-specific PCR, semi-quantitative RT-PCR, and real-time quantitative PCR in HCC tissues and cell lines, and further analyzed from The Cancer Genome Atlas database. Wound healing assay, transwell migration, cell viability, and colony formation assay were performed to investigate the function of RNF135. GSEA analysis, TIMER database, and ESTIMATE algorithm were used to decipher the associated pathway and immune infiltration. The survival analysis was applied to assess the prognostic value of RNF135. RNF135 expression was downregulated in HCC tissues and 5 of 8 HCC cell lines, and was negatively correlated with its promoter hypermethylation. Demethylating regent decitabine restored RNF135 expression on the cellular level. Knockdown of RNF135 expression enhanced the migration of HCC cells, while RNF135 overexpression and decitabine treatment repressed cell migration. Bioinformatics analysis and immunohistochemistry revealed a positive relationship between RNF135 expression and six immune cell infiltrates (B cells, CD4+ T cells, CD8+ T cells, neutrophils, macrophages, and dendritic cells). Survival analysis disclosed that RNF135 hypermethylation is independently associated with poor clinical outcomes in HCC. Decreased RNF135 expression driven by promoter hypermethylation frequently occurred in HCC and associated with prognosis of HCC. RNF135 functions as a tumor suppressor and is involved in tumor immune microenvironment in HCC.