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Chicken infectious anemia (CIA) is caused by chicken anemia virus (CAV). Recently, severe anemia has emerged in layer chickens (8 to 10-week-old) on poultry farms in China. However, the etiological characteristics and pathogenic potential of CAV in chickens at 6 weeks or older are not well understood. In this study, we isolated a CAV strain, termed SD15, from two-month-old chicken with severe anemia and analyzed the genetic evolution relationship. We found that strain SD15 had the highest homology (98.9%) with CAV18 strain. Comparison with 33 reference strains revealed 16 amino acid mutations in strain SD15, two of which were previously unknown (F210S in VP1 and L25S in Vp3). Compared with low pathogenic strains (Cux-1 and C14), highly pathogenic strains (SDLY08 and SD15) had three basemutations in their noncoding region. To further understand its pathogenicity, 10-week-old specific-pathogen-free (SPF) chickens were challenged with the novel strain and SDLY08. No obvious clinical symptoms were observed in the SDLY08 group. However, SD15-infected chickens showed significant growth retardation and immunosuppression. Themainmanifestations of immunosuppression were the significantly reduced thymus and bursa indices and AIV-H9 vaccine-induced antibody levels (P < 0.05). The lowest number of red blood cells in the SD15 group was just 60% of that in the control group. Taken together, the novel strain SD15 not only showed higher pathogenicity but also exhibited the potential ability to break the age resistance of older chickens to CAV. Our study enhanced the understanding of the epidemiological characteristics of chickens infected with severe anemia and can facilitate the development of improved control strategies of CIA in China. [ABSTRACT FROM AUTHOR]

Hepatitis E virus (HEV) is relevant to public health worldwide, and it affects a variety of animals. Big liver and spleen disease (BLS) and hepatitis-splenomegaly syndrome (HSS) associated with avian HEV (aHEV) were first reported in 1988 and in 1991, respectively. Here, cell culture-adapted aHEV genotype 3 strain, YTaHEV (YT strain), a typical genotype isolated in China, was used for basic and applied research. We evaluated liver injury during the early stages of infection caused by the YT strain in vivo. Both in vivo and in vitro experimental data demonstrated that viral infection induces innate immunity, with mRNA expression levels of two key inflammatory factors, interleukin-1b (IL-1β) and IL-18, significantly upregulated. The YT strain infection was associated with the activation of Toll-like receptors (TLRs), nuclear factor kappa B (NF-kB), caspase-1, and NOD-like receptors (NLRs) in the liver and primary hepatocellular carcinoma epithelial cells (LMH). Moreover, inhibiting c-Jun N-terminal kinase, extracellular signal-regulated kinase (ERK1 or 2), P38, NF-kB, or caspase-1 activity has different effects on NLRs, and there is a mutual regulatory relationship between these signaling pathways. The results show that SB 203580, U0126, and VX-765 inhibited IL-1β and IL-18 induced by the YT strain, whereas Pyrrolidinedithiocarbamate (PDTC) had no significant effect on the activity of IL-1β and IL-18. Pretreatment of cells with SP600125 had an inhibitory effect on IL-18 but not on IL-1β. The analysis of inhibition results suggests that there is a connection between Mitogen-activated protein kinase (MAPK), NF-kB, and the NLRs signaling pathways. This study explains the relationship between signaling pathway activation (TLRs, NF-kB, MAPK, and NLR-caspase-1) and viral-associated inflammation caused by YT strain infection, which will help to dynamic interaction between aHEV and host innate immunity. [ABSTRACT FROM AUTHOR]

Well-defined key competencies for students with autism spectrum disorders (ASD) help develop curriculum and pedagogies that emphasize what students with ASD are expected to learn, to know and to do. Most of the current research on the key competencies of ASD is theoretical and based on the social and cultural backgrounds of western countries. The key competencies defined by most of the research lack of the support of empirical evidence. This study sought to identify the key competencies of school-age students with ASD from the perspectives of teachers and parents. Based on the review of existing key competencies frameworks, a key competencies instrument that consisted of 76 learning outcome items in eight domain areas was developed. An online survey to explore the teachers' and parents' views of the key competencies was conducted with 1,618 teachers and 2,430 parents of students with ASD across China. The results showed that teachers believed that the key competencies should consist of eight domain areas including socialcommunication, learning skills, healthy living, play, motor, emotion, sensory processing, and cognition, while the cognition related competencies were not recognized by parents. The competencies in social-communication, learning skills, healthy living had higher variance contribution. From the perspective of teachers, the variance contribution of social communication was the highest, while from the perspective of parents, the variance contribution of learning skills was the largest. Taken together, the key competencies framework for students with ASD should include eight dimensions and 75 learning outcome items. The similarities and differences between the perspectives of the two group were discussed. The findings could provide empirical data to assist in developing educational guidelines and guide the development of models of support for students with ASD. [ABSTRACT FROM AUTHOR]

A total of 45 moderately halophilic bacteria was isolated from sediment and saline water collected from the Weihai Solar Saltern (China). The phylogenetic position of all the isolated strains was determined by 16S rRNA sequencing. The halophilic strains were tested for their antimicrobial activity. Cytotoxicity assay was performed to determine which of the halophilic strains could inhibit proliferation of human hepatocellular carcinoma Bel 7402 cells. Our results showed that all of the isolated 45 strains displayed moderately halophilic characteristics. Phylogenetic analysis indicated that 17 of the isolated strains were related to the phylum Firmicutes and belonged to four genera, Bacillus, Halobacillus, Planococcus and Salinicoccus. The other strains identified as genus of Halomonas belonged to phylum γ-Proteobacteria. Most of the halophilic bacterial strains showed potent activities against Gram-positive bacteria, human pathogenic fungi and plant pathogenic fungi. In addition, the crude extracts from 14 halophilic bacterial strains showed cytotoxic activity against tumor cells Bel 7402, and five of them showed remarkable activities with IC50 less than 40 μg ml−1. Our results suggest that the moderately halophilic bacteria may be developed as promising sources for the discovery of novel bioactive substances. [ABSTRACT FROM AUTHOR]

• Farmland shelterbelt systems (FSSs) can improve ecosystem functions over controls. • Environmental factors exhibit spatiotemporal heterogeneities in different FSSs. • Different patterns of FSSs had beneficial water retention and nutrient supply functions. • There were close relationships between environmental factors and ecosystem functions in FSSs. • Results provide a theoretical basis for ecological restoration in ecofragile regions. The farmland shelterbelt system is considered an effective form of land management to improve the eco-environment and soil quality in fragile agricultural areas. Clarifying the effects of farmland shelterbelt patterns on ecosystem functions can guide ecological restoration in fragile ecosystems. Four typical farmland shelterbelt patterns (i.e., two-line pattern, four-line pattern, five-line pattern, and eight-line pattern) in desert oasis ecotones of Hetao irrigated area, northern China, were selected in this study. In these treatments, measurements of soil properties at a depth of 0–100 cm; vegetation attributes; microclimate; and soil water, carbon, nitrogen, and phosphorus storage were performed during three growing seasons in 2019–2021. The results demonstrated that the four-line pattern had higher soil organic content (0.339 g·kg−1), total nitrogen content (0.517 g·kg−1), and total phosphorus content (0.577 g·kg−1) than the other treatments, as well as the highest soil water (237.44 mm), carbon (544.93 g·m−2), nitrogen (953.72 g·m−2), and phosphorus storage (859.04 g·m−2) at the 0–100-cm soil layer. Moreover, dynamic variations in soil water and salt contents showed opposite trends during the growing season, i.e., they showed a gradual decrease and increase, respectively. Furthermore, principal component analysis, correlation matrix analyses, and network association analyses indicated close relationships among environmental factors, nutrient storage, and related ecosystem functions under different farmland shelterbelt patterns. The results of this investigation provide a useful theoretical basis for agricultural management and ecological restoration in ecofragile regions. [ABSTRACT FROM AUTHOR]

Farmland shelterbelt system (FSS) in oasis desert ecotones can effectively improve ecosystem services, especially in fragile agricultural areas. However, the spatial-temporal heterogeneity of its ecological effects still needs further clarity, because the interactions are complex and multiple. Understanding this allows us to know the key practical significance of ecological construction and agricultural management. In this study, four typical patterns of FSS (i.e. two lines pattern, TWLP; four lines pattern, FOLP; five lines pattern, FILP; eight lines pattern, EILP) were selected in a desert oasis ecotone in northern China to assess the distributions at vertical (0–100 cm), horizontal (0–3 H) and temporal (May- October) scales of soil properties, vegetation attributes, microclimates and variations of soil moisture storage (SMS) and soil salt contents (C) during the three growing seasons. The results showed that the major difference in soil properties and vegetation attributes of FSSs are the soil particle composition and canopy size, respectively. In FOLP and EILP, the silt contents were 51.6% and 41.5% respectively. The canopy size ranked from the highest to lowest values as follows: FOLP (8.70 m2) > EILP (6.91 m2) > TWLP (4.64 m2) > FILP (4.47 m2). Compared to the control, all patterns of FSSs registered significant effects on microclimate improvement. The FOLP and FILP achieved the same effects as well as EILP, with less spatial costs. Moreover, the variations of SMS and C were mainly different at the vertical scale. As indicated by the Redundancy (RDA) and variation partitioning (VP) analyses, soil properties played a more important role in reserving soil water and controlling soil salinity than vegetation attributes and microclimates, which the independent influence can explain 48.5% of total influence among all factors. Our results provide an efficient theoretical basis for FSS construction and agricultural water management practices. • Farmland shelterbelt system (FSS) can improve ecosystem services. • A spatio-temporal heterogeneity of ecosystem functions in FSSs is observed. • Soil properties play a more important role in controlling soil water content and salinity. • Results provide an efficient theoretical basis for agricultural water management in deserts. [ABSTRACT FROM AUTHOR]