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Ammonia-oxidizing archaea (AOA) of the phylum Thaumarchaeota are widespread in marine and terrestrial habitats, playing a major role in the global nitrogen cycle. However, their evolutionary history remains unexplored, which limits our understanding of their adaptation mechanisms. Here, our comprehensive phylogenomic tree of Thaumarchaeota supports three sequential events: origin of AOA from terrestrial non-AOA ancestors, colonization of the shallow ocean, and expansion to the deep ocean. Careful molecular dating suggests that these events coincided with the Great Oxygenation Event around 2300 million years ago (Mya), and oxygenation of the shallow and deep ocean around 800 and 635-560 Mya, respectively. The first transition was likely enabled by the gain of an aerobic pathway for energy production by ammonia oxidation and biosynthetic pathways for cobalamin and biotin that act as cofactors in aerobic metabolism. The first transition was also accompanied by the loss of dissimilatory nitrate and sulfate reduction, loss of oxygen-sensitive pyruvate oxidoreductase, which reduces pyruvate to acetyl-CoA, and loss of the Wood-Ljungdahl pathway for anaerobic carbon fixation. The second transition involved gain of a K+ transporter and of the biosynthetic pathway for ectoine, which may function as an osmoprotectant. The third transition was accompanied by the loss of the uvr system for repairing ultraviolet light-induced DNA lesions. We conclude that oxygen availability drove the terrestrial origin of AOA and their expansion to the photic and dark oceans, and that the stressors encountered during these events were partially overcome by gene acquisitions from Euryarchaeota and Bacteria, among other sources.

Using the Weather Research and Forecasting model with two planetary boundary layer schemes, ACM2 and MYNN, convection‐permitting model (CPM) regional climate simulations were conducted for a 6‐year period, including a one‐year spin‐up period, at a 15‐km grid spacing covering entire South America and a nested convection‐permitting 3‐km grid spacing covering the Peruvian central Andes region. These two CPM simulations along with a 4‐km simulation covering South America produced by National Center for Atmospheric Research (NCAR), three gridded precipitation products, and rain gauge data in Peru and Brazil, are used to document the characteristics of precipitation and mesoscale convective systems (MCSs) in the Peruvian central Andes region. Results show that all km‐scale simulations generally capture the spatiotemporal patterns of precipitation and MCSs at both seasonal and diurnal scales, although biases exist in aspects such as precipitation intensity and MCS frequency, size, propagation speed, and associated precipitation intensity. The 3‐km simulation using MYNN scheme generally outperforms the other simulations in capturing seasonal and diurnal precipitation over the mountain, while both it and the 4‐km simulation demonstrate superior performance in the western Amazon Basin, based on the comparison to the gridded precipitation products and gauge data. Dynamic factors, primarily low‐level jet and terrain‐induced uplift, are the key drivers for precipitation and MCS genesis along the east slope of the Andes, while thermodynamic factors control the precipitation and MCS activity in the western Amazon Basin and over elevated mountainous regions. The study suggests model improvements and better model configurations for future regional climate projections. Plain Language Summary: We ran high‐resolution model simulations at a 3‐km grid spacing with ACM2 and MYNN planetary boundary layer schemes for a 6‐year period, including a 1‐year spin‐up, to investigate precipitation and storm patterns in the Peruvian central Andes region. Other data sets including a 4‐km simulation produced by National Center for Atmospheric Research, three gridded precipitation products, and rain gauge data in Peru and Brazil were collected for comparison and evaluation. We found that all km‐scale simulations capture overall patterns of precipitation and storms at both seasonal and sub‐daily time scales, although some discrepancies exist in precipitation intensity and storm details. Compared to the gridded precipitation products and gauge data, the 3‐km simulation using MYNN scheme generally outperforms the other simulations in capturing seasonal and diurnal precipitation over the mountain, while both it and the 4‐km simulation demonstrate superior performance in the western Amazon Basin. Low‐level wind and terrain‐induced uplift are the key drivers for precipitation and storm genesis along the Andes' eastern slopes, while factors associated with vertical structures of temperature and humidity control the precipitation and storm activity in the western Amazon Basin and mountain regions. The study suggests model improvements and better model configurations for future regional climate projections. Key Points: Characteristics of precipitation and mesoscale convective systems (MCSs) in the Peruvian Central Andes are investigated based on convection‐permitting simulationsWRF3km_MYNN outperforms in simulating mountain precipitation; both it and WRF4km_SAAG show superior performance in western AmazonDynamic factors dominate precipitation and MCSs on the Andean east slope, while thermodynamic factors are dominant in western Amazon Basin [ABSTRACT FROM AUTHOR]

The article systematically sorted out the microbial taxa and dominant species present on the surface of activated carbon, in which Bacteroidetes and Proteobacteria are often the dominant phyla among prokaryotes, and eukaryotes are dominated by protozoa and microscopic metazoans; and the potential functions of certain dominant phyla in the pollutant removal process are summarised, and most of them are aerobic chemoorganotrophic heterotrophic microorganisms. Possible risk microorganisms were also explored, with the water-source chlorine-tolerant bacterial pathogens belonging to the Actinobacteridae, Bacilli and Gammaproteobacteria; and factors affecting the microbial community were summarised, including carriers, water quality, residual ozone, and influent water flow direction. The results are expected to provide theoretical basis and technical support for the precise regulation of ozone/ biological activated carbon filter in drinking water treatment plants. [ABSTRACT FROM AUTHOR]

Intermittent hypoxia (IH) is a hallmark of obstructive sleep apnea (OSA), which is related to tumorigenesis and progression. We explored the possible mechanisms by which OSA may promote the development of non‐small cell lung cancer (NSCLC). In this study, NSCLC cells with and without miR‐106a‐5p inhibition were exposed to IH or room air (RA), and subsequently, exosomes were extracted and identified. Macrophages were incubated with these exosomes to detect the expression of the STAT3 signaling pathway and M2‐type macrophage markers, as well as the effect of the macrophages on the malignancy of NSCLC cells. A nude mouse tumorigenesis model was constructed to detect the effects of exosomal miR‐106a‐5p on M2 macrophage polarization and NSCLC cell malignancy. Our results showed that IH exosomes promoted the polarization of M2 macrophages, thereby promoting the proliferation, invasion, and metastasis of NSCLC cells. Further, Based on microarray analysis of RA and IH exosomes, we discovered that miR‐106a‐5p, transferred to the macrophages through exosomes, participated in this mechanism by promoting M2 macrophage polarization via down‐regulating PTEN and activating the STAT3 signaling pathway in vitro and in vivo. For patients with NSCLC and OSA, exosomal miR‐106a‐5p levels showed a positive relation to AHI. Exosomal miR‐106a‐5p represents a potential therapeutic target among patients with concomitant cancer and NSCLC. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) pollution has been rapidly increasing due to the global rise in industries. Cd not only harms the ecological environment but also endangers human health through the food chain and drinking water. Therefore, the remediation of Cd-polluted soil is an imminent issue. In this work, ryegrass and a strain of Cd-tolerant bacterium were used to investigate the impact of inoculated bacteria on the physiology and biochemistry of ryegrass and the Cd enrichment of ryegrass in soil contaminated with different concentrations of Cd (4 and 20 mg/kg). The results showed that chlorophyll content increased by 24.7% and 41.0%, while peroxidase activity decreased by 56.7% and 3.9%. In addition, ascorbic acid content increased by 16.7% and 6.3%, whereas glutathione content decreased by 54.2% and 6.9%. The total Cd concentration in ryegrass increased by 21.5% and 10.3%, and the soil's residual Cd decreased by 86.0% and 44.1%. Thus, the inoculation of Cd-tolerant bacteria can improve the antioxidant stress ability of ryegrass in Cd-contaminated soil and change the soil's Cd form. As a result, the Cd enrichment in under-ground and above-ground parts of ryegrass, as well as the biomass of ryegrass, is increased, and the ability of ryegrass to remediate Cd-contaminated soil is significantly improved. [ABSTRACT FROM AUTHOR]

The tensile and compressive mechanical properties of laminates repaired by injection repair were experimentally studied, and the influences of repair on strength, stiffness and failure mode were evaluated. Control experiments between pristine, damaged and repaired specimens were designed, which including tensile and buckling unrestrained compression. The strain gauges were used to collect the deformation data in the test, and all the experimental data were analyzed and explained. The results demonstrate that strength of half-depth damage laminates is partially restored after repair. Strength recovery rate of tensile strength is 73.7% and that of buckling is 77.4%, and the weakest area is a filling area or the interface of panel and filler. Strength and stiffness of damaged specimens are reduced due to the coupling between extension/ compression and bending load as well as stress concentration, which are caused by the missing of material in damaged area. The stiffness of filler is smaller than that of motherboard, and the filler reduces the asymmetry of the damaged laminates and increases the stiffness of the repaired laminates.