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Soil salinity is a threat to agricultural production worldwide. Oat (Avena sativa L.) is an irreplaceable crop in areas with fragile ecological conditions. However, there is a lack of research on salt tolerance evaluation of oat germplasm resources. Therefore, the purpose of this work was to evaluate the salt tolerance of oat cultivars and investigate the mechanism of salt-tolerant oat cultivars' adaptation to salinity. Salt tolerance of 100 oat cultivars was evaluated, and then two salt-tolerant cultivars and two salt-sensitive cultivars were used to compare their physiological responses and expression patterns of Na

Seismic fragility provides a measure for evaluating the safety margin of structures above specific hazard levels. This study investigates the seismic fragility of arch dams using the dynamic damage analysis model of dam–reservoir–foundation systems, in which the radiation damping of semi-unbounded foundation rock, opening of contraction joints, and damage cracking of dam concrete are taken into account. The 210 m-high Dagangshan Dam in Southwest China is analyzed as a case study. Five hundred nonlinear damage analyses are performed using the Monte Carlo simulation technique considering both epistemic and aleatory uncertainties, which are characterized by random material parameters and ground motions, respectively. Three limit states, i.e., slight damage, moderate damage, and severe damage, are proposed according to the calculated damage distribution and joint opening, and seismic fragility curves are subsequently generated using the incremental dynamic analysis approach. Analysis results show that the Dagangshan Dam may be severely damaged by strong earthquakes when uncertainties in material parameters and ground motions are considered.

Viral reservoirs of HIV-1 are a major obstacle for curing AIDS. The novel animal models that can be directly infected with HIV-1 will contribute to develop effective strategies for eradicating infections. Here, we inoculated 4 northern pig-tailed macaques (NPM) with the HIV-1 strain HIV-1NL4.3 and monitored the infection for approximately 3 years (150 weeks). The HIV-1-infected NPMs showed transient viremia for about 10 weeks after infection. However, cell-associated proviral DNA and viral RNA persisted in the peripheral blood and lymphoid organs for about 3 years. Moreover, replication-competent HIV-1 could be successfully recovered from peripheral blood mononuclear cells (PBMCs) during long-term infection. The numbers of resting CD4+ T cells in HIV-1 infected NPMs harboring proviruses fell within a range of 2- to 3-log10 per million cells, and these proviruses could be reactivated both ex vivo and in vivo in response to co-stimulation with the latency-reversing agents JQ1 and prostratin. Our results suggested that NPMs can be infected with HIV-1 and a long-term viral reservoir was formed in NPMs, which might serve as a potential model for HIV-1 reservoir research.

Owing to modern developments in the traditional medicine industry, more people now acknowledge the efficacy of traditional medicine. As the demand for herbal medicines gradually increases, the focus of the industry will shift to how to increase production while maintaining the high quality of raw materials and final products to promote the international trade in herbal medicines. In the long history of herbal medicine, many countries and regions have formulated relevant standards to regulate the cultivation of local herbs to ensure the safety and reliability of the products. Due to cultural and historical differences, the policies for formulating herbal cultivation standards vary greatly between regions, which hinders the international trade of herbal medicines. This paper collates the guidelines of good agricultural and collection practices of the European Union, China, World Health Organization and the United States, and makes a comprehensive comparison of its contents such as production environments, production area suitability, air, soil, and water standard regulations, inter alia. This article aims to explore the differences in good agriculture and collection practice in herbal medicine in various regions and provides a reference for the development of international guidelines for herbal quality management, which will aid with the development of herbal medicine quality standardization globally and exchange services in the trade of herbal medicines.

The elderly usually suffer from increased morbidity and mortality due to infectious diseases, and this process may be attributed to diminishing immune protection with age. This phenomenon is commonly referred to as immunosenescence. However, this theory is still not well defined. Non-human primates serve as a favorable model to facilitate the study in aging of the immune system. Here, we investigated the phenotypic features of T- and B-cell aging in peripheral blood from Chinese rhesus macaques, which included (1) a decrease of CD4/CD8 ratio; (2) a loss of naïve T cells accompanied with elevated proliferation and expansion of effector memory subset; (3) a reduction in B cell numbers and a shift from naïve B cells towards memory phenotype; and (4) increased levels of PD-1 expression in T cells and CD95 expression in B cells. Moreover, an accelerated decline in CD4(+) T cells and naïve T cells was found in male macaques, giving them a more severe immune risk profile. These data indicated that Chinese rhesus macaques share a significant homology with humans in phenotypic aging of adaptive immunity, and may be an appropriate animal model for human aging research.