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The reuse of wastewater is a key problem in controlled ecological life support system (CELSS). In this study, the feasibility to reuse the treated wastewater (including sanitary wastewater and urine wastewater) as a plant hydroponic medium was verified. Two salt-tolerant plants, apium graveolens Linn (celery) and mesembryanthemum cordifolium L.F. (cordifolium), were cultivated with the reused medium or Hoagland nutrient solution, and the characteristics of crop growth, hydroponic medium composition, and elements absorption by plants were investigated. The results showed that the reused medium replenished with micronutrient elements could maintain the normal growth of cordifolium and celery crops. The biomass productivity of cordifolium cultivated by the recycled medium (121.53 g FW/strain) was higher than that cultivated by Hoagland nutrient solution (98.33 g FW/strain). The nutrient elements accumulation in plant dry mass indicated that plants could effectively utilize the recycled mineral elements in wastewater, and cordifolium exhibited better stability and adaptability to salt-induced environment. The absorption capacity of Na and Cl elements in cordifolium cultivated within the reused medium was the highest, which was 4.54% DW and 2.63% DW, respectively. This study demonstrated the feasibility to directly reuse domestic wastewater as the main ingredient for plant hydroponics, which could provide insights into design and operation of plant hydroponics system and water circulation system in CELSS.

Sustainability has been a concern of survival for future long-term manned space missions. Therefore, the wastewater generated by the crew members, containing urine and hygiene wastewater, should be treated with appropriate biological processes to promote recycling efficiency. In this study, we developed a membrane-aerated biofilm reactor (MABR) that could achieve up to 96% total organic carbon (TOC) removal efficiency and up to 82% denitrification efficiency for an influent with 370–390 mg/L TOC and 500–600 mg/L total nitrogen (TN) without additional carbon source or sludge discharge. The nitrogen removal rate was about 100 mg N L−1 d−1. Metagenomic analysis indicated the presence of a variety of nitrifying, denitrifying, and anammox bacteria in the microbial community and existence of functional genes in nitrification, denitrification, and anammox pathways.

Abstract Gullies with lower altitudes compared to the surrounding environment are widely distributed in farmland of the watershed and their numbers are still expanding. However, it is still unclear how these gullies regulate the functional insects in farmland. In this study, land use types combined with the herbaceous plant, herbicide application, soil moisture, topography and climatic factors during crop growth were considered to understand how gullies influence the dynamics of functional insects in farmland from a watershed (240 ha) of Northeast China. The primary findings demonstrate that the richness and abundance of functional insects are generally greatest in gullies, particularly in stable gullies, and decrease in the following order: forest belts, grasslands, and farmlands within the watershed. Notably, the ratios of beneficial insects to pests (BI/Pest) in terms of richness and abundance were lower in gullies before July but reversed after July, in comparison to farmland. Stable gullies exhibited higher BI/Pest abundance and diversity ratios than developing gullies. The richness and abundance of functional insects were higher in the middle sections of gullies compared to their heads and tails. Furthermore, the ratios of BI/Pest were generally lower in farmlands than in any gully position. Functional insect dynamics were mainly determined by season, followed by plant abundance and biomass in the gullies, and rarely by soil moisture in the both watershed and single gullies scales. Generally, the richness and abundance of functional insects in farmland were mainly influenced by gullies, especially influenced by the gully middle position. Insect composition in farmland influenced by stable gullies was stronger than by developing gullies, and stable gullies were more beneficial in reducing the threat of pests to crops in the farmland of the watershed.

Two novel reassortant highly pathogenic avian influenza viruses (H5N1) clade 2.3.4.4b.2 were identified in dead migratory birds in China in November 2021. The viruses probably evolved among wild birds through different flyways connecting Europe and Asia. Their low antigenic reaction to vaccine antiserum indicates high risks to poultry and to public health.

Rheumatoid arthritis (RA) is a chronic, autoimmune pathology characterized by persistent synovial inflammation and gradually advancing bone destruction. Matrix metalloproteinases (MMPs), as a family of zinc-containing enzymes, have been found to play an important role in degradation and remodeling of extracellular matrix (ECM). MMPs participate in processes of cell proliferation, migration, inflammation, and cell metabolism. A growing number of persons have paid attention to their function in inflammatory and immune diseases. In this review, the details of regulation of MMPs expression and its expression in RA are summarized. The role of MMPs in ECM remodeling, angiogenesis, oxidative and nitrosative stress, cell migration and invasion, cytokine and chemokine production, PANoptosis and bone destruction in RA disease are discussed. Additionally, the review summarizes clinical trials targeting MMPs in inflammatory disease and discusses the potential of MMP inhibition in the therapeutic context of RA. MMPs may serve as biomarkers for drug response, pathology stratification, and precision medicine to improve clinical management of rheumatoid arthritis.

The gut microbiome is closely related to host nutrition and health. However, the relationships between gut microorganisms and host lifestyle are not well characterized. In the absence of confounding geographic variation, we defined clear patterns of variation in the gut microbiomes of Asian elephants (AEs) in the Wild Elephant Valley, Xishuangbanna, China, along a lifestyle gradient (completely captive, semicaptive, semiwild, and completely wild). A phylogenetic analysis using the 16S rRNA gene sequences highlighted that the microbial diversity decreased as the degree of captivity increased. Furthermore, the results showed that the bacterial taxon WCHB1-41_c was substantially affected by lifestyle variations. qRT-PCR analysis revealed a paucity of genes related to butyrate production in the gut microbiome of AEs with a completely wild lifestyle, which may be due to the increased unfavorable environmental factors. Overall, these results demonstrate the distinct gut microbiome characteristics among AEs with a gradient of lifestyles and provide a basis for designing strategies to improve the well-being or conservation of this important animal species.

Highly pathogenic influenza A(H5N8) viruses have caused several worldwide outbreaks in birds and are able cross the species barrier to infect humans, posing a substantial threat to public health. After the first detection of H5N8 viruses in deceased swans in Inner Mongolia, we performed early warning and active monitoring along swan migration routes in central China. We isolated and sequenced 42 avian influenza viruses, including 40 H5N8 viruses, 1 H5N2 virus, and 1 H9N2 virus, in central China. Our H5N8 viruses isolated in swan stopover sites and wintering grounds showed high nucleotide homologies in the whole genome, revealing a common evolutionary source. Phylogenetic analysis revealed that the H5 viruses of clade 2.3.4.4b prevalent in 2020 have further diverged into two sub-clades: b1 and b2. The phylogeographic analysis also showed that the viruses of sub-clade b2 most likely originated from poultry in Russia. Notably, whooper swans were found to be responsible for the introduction of sub-clade b2 viruses in central China; whooper and tundra swans play a role in viral spread in the Yellow River Basin and the Yangtze River Basin, respectively. Our findings highlight swans as an indicator species for transborder spreading and monitoring of the H5N8 virus.

The rare northward migration of wild Asian elephants in Xishuangbanna, China, has attracted global attention. Elephant migration is a complex ecological process, and the factors driving this long-distance migration remain elusive. In this study, fresh fecal samples were collected from both captive and wild Asian elephants, along with breastfed calves residing within the Wild Elephant Valley of Xishuangbanna. Our aim was to investigate the relationship between diet, gut microbiota, and migration patterns in Asian elephants through comprehensive metagenomic sequencing analyses. Among the breastfed Asian elephant group, Bacteroidales and Escherichia emerged as the dominant bacterial taxa, while the primary carbohydrate-active enzymes (CAZymes) enriched in this group were GH2, GH20, GH92, GH97, GH38, GH23, and GH43, aligning with their dietary source, namely breast milk. The bacterial taxa enriched in captive Asian elephants (CAEs) were mainly Butyrivibrio, Treponema, and Fibrobacter, and the enriched lignocellulose-degrading enzymes mainly included GH25, GH10, GH9, and cellulase (EC 3.2.1.4). These findings are consistent with the high-fiber diet of captive elephants. In contrast, the main bacterial taxa enriched in wild Asian elephants (WAEs) were Ruminococcus and Eubacterium, and the enriched CAZymes included GH109, GH20, GH33, GH28, GH106, and GH39. The abundance of lignocellulose-degrading bacteria and CAZyme content was low in WAEs, indicating challenges in processing high-fiber foods and explaining the low-fiber diet in this group. These findings suggest that wild elephant herds migrate in search of nutritionally suitable, low-fiber food sources.

The performance of weaned piglets suffers from severe limitations resulting from diarrhoea. Therefore, this trial was performed to investigate the effects of Bacillus coagulans as an alternative to antibiotics on piglet growth performance and intestinal health. Ninety (initial BW = 7.70 ± 0.17 kg, weaning age of 26 days) healthy weaned piglets with similar BWs were selected and randomised into three treatment groups. Pigs in the negative control (NC) group were fed a basal diet, pigs in the positive control (PC) group were fed the basal diet plus antibiotics, and pigs in the test group (BC) were fed the basal diet plus Bacillus coagulans at 600 g/t; the trial lasted for 28 days. The results showed that the ratios of feed to gain (F:G) of both the BC and PC groups from 1 to 21 days were significantly lower (P

Myocardial ischemia/reperfusion injury (MIRI) is related to ferroptosis and apoptosis elicited by reactive oxygen species (ROS). In this research, we investigated the protective effect of salvianolic acid B (SAB) as a natural antioxidant on ferroptosis and apoptosis in the MIRI process, and discussed the protective mechanism inhibiting ubiquitin-proteasome degradation of glutathione peroxidase 4 (GPX4) and the c-Jun N-terminal kinases (JNK) apoptosis signal pathway. We observed that ferroptosis and apoptosis occurred in the MIRI rat model in vivo and the H9c2 cardiomyocyte hypoxia/reoxygenation (H/R) damage model in vitro. SAB can alleviate tissue damage related to ROS, ferroptosis and apoptosis. Ubiquitin-proteasome degradation of GPX4 occurred in H/R models, and SAB reduced the ubiquitin-proteasome degradation of GPX4. SAB downregulates JNK phosphorylation and the expression of BCL2-Associated X (Bax)/B-cell lymphoma-2 (Bcl-2) and Caspase-3 to inhibit apoptosis. The role of GPX4 in the cardioprotection of SAB was further verified by the elimination effect of the GPX4 inhibitor RAS-selective lethal 3 (RSL3). This research shows that SAB may be used as a myocardial protective agent against oxidative stress, ferroptosis and apoptosis, and has potential clinical application prospects.

Evaluating the association between milk-containing diets and the microbiomes of young Asian elephants could assist establishing optimal breast milk supplementation to improve offspring survival rates. The microbiomes of young Asian elephants on different milk-containing diets (elephant milk only, elephant milk–plant mixed feed, and goat milk–plant mixed feed) were investigated using high-throughput sequencing of 16S rRNA genes and phylogenetic analysis. Microbial diversity was lower in the elephant milk-only diet group, with a high abundance of Proteobacteria compared to the mixed-feed diet groups. Firmicutes and Bacteroidetes were dominant in all groups. Spirochaetae, Lachnospiraceae, and Rikenellaceae were abundant in the elephant milk–plant mixed-feed diet group, and Prevotellaceae was abundant in the goat milk–plant mixed-feed diet group. Membrane transport and cell motility metabolic pathways were significantly enriched in the elephant milk–plant mixed-feed diet group, whereas amino acid metabolism and signal transduction pathways were significantly enriched in the goat milk–plant mixed-feed diet group. The intestinal microbial community composition and associated functions varied significantly between diets. The results suggest that goat milk is not suitable for young elephants. Furthermore, we provide new research methods and directions regarding milk source evaluation to improve elephant survival, wellbeing, and conservation.

An undisturbed and well-controlled hearth state is an essential prerequisite for achieving a long campaign life and low production costs in an ironmaking blast furnace, because hearth wear and hot metal and slag drainage are crucial factors in its operation. With the objective to estimate the hearth state of the refractory of a three-taphole blast furnace, a wear model of the hearth erosion and skull formation was developed. The model is based on thermocouple readings in the hearth lining and solves an inverse heat conduction problem for a series of co-axial vertical slices, where the erosion and skull lines are optimized simultaneously. The model is optimized for fast computation by adopting a novel procedure featuring fixed mesh during the looping calculation. The results revealed that the hearth refractory showed an elephant-foot-shaped profile with excessive erosion in the hearth periphery, indicating that liquid flows are suppressed in the hearth bottom and that the permeability of the core of the deadman is low. These findings were further elaborated and confirmed by a comparison between the estimated hearth state and other key operation variables, including the coke rate, blast kinetic energy, and residual carbon appetite of the hot metal.