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• Three H3N8 subtype low pathogenic avian influenza viruses were isolated from wild birds in China during the ordinary surveillance. • The H3N8 from wild birds in the study clustered with two emerged human H3N8 viruses in 2022 in the same Eurasian avian lineage. • The H3N8 from wild birds in the study presented dual receptors preferences. • The H3N8 from wild birds in the study replicated well in mammalian model without prior adaption. We present the phylogeny, receptor binding property, growth in mammal cells and pathogenicity in mammal model of H3N8 viruses, which were isolated from wild birds in China. The human receptor preference and efficient replication in mice without prior adaption highlight that the H3N8 virus possesses the public threat potential. [ABSTRACT FROM AUTHOR]

Fire size and fire frequency are important indicators of fire characteristics. Characterizing fire size and fire frequency and understanding its environmental controls are indispensable to fire prediction and sustainable forest landscape management. In this paper, we determined the mean number of fires and the mean forest area burned by province to define five distinct patterns of fires across China by cluster analysis for the period 1987–2007. Then, we performed Redundancy Analysis (RDA) to explore factors influencing the spatial variation in the mean number of fires and the mean forest area burned, and to determine their relative contributions to this variation. Results showed that the north part of China generally had low mean number of fires. Percentage of the total number of fires in northeastern, northern and northwestern region to the total number of fires in whole country is 3.49%, 3.18% and 2.19% respectively. Neimenggu and Heilongjiang had larger mean burned forest area with 208,786 and 103,018 ha respectively. RDA analysis showed that the percentage of forest land and de Martonne aridity had significant impacts on the spatial variation in forest fire characteristics over China ( p < 0.05). These two variables and their interactions explained 44.9% of the total variance of the mean number of forest fires and mean forest area burned (63%), out of which 8.2% was explained by percentage of forest land, 11.7% by de Martonne aridity and 25.0% by their interactions. [ABSTRACT FROM AUTHOR]

Abstract: It is well recognized that harsh outer space environment, consisting of microgravity and radiation, poses significant health risks for human cells. To investigate potential effects of the space environment exposure on cancer cells we examined the biological changes in Caski cells carried by the “Shen Zhou IV” spaceship. After exposure for 7 days in spaceflight, 1440 survival subclonal cell lines were established and 4 cell lines were screened. 44F10 and 17E3 were selected because of their increased cell proliferation and tumorigenesis, while 48A9 and 31F2 had slower cytological events. Experiments with cell proliferation assay, flow cytometry, soft agar assay, tumorigenesis assay and DNA microarray analysis have shown that selected cell lines presented multiple biological changes in cell morphology, cell growth, tumorigenicity and gene expression. These results suggest that space environment exposure can make significant biological impact on cancer cells and provide an entry point to find the immunological target of tumorigenesis. [Copyright &y& Elsevier]

Domain walls are of increasing interest in ferroelectrics because of their unique properties and potential applications in future nanoelectronics. However, the thickness of ferroelastic domain walls remains elusive due to the challenges in experimental characterization. Here, we determine the atomic structure of ferroelastic domain walls and precisely measure the polarization and domain wall thickness at picometer scale using annular bright field imaging from an aberration-corrected scanning transmission electron microscope. We find that the domain wall thickness in PbZr 0.2 Ti 0.8 O 3 and PbTiO 3 thin films is typically about one unit cell, across which the oxygen octahedron distortion behavior is in excellent agreement with previous first-principles calculations. Remarkably, wider domain walls about two unit cells in thickness are also observed for those domains walls are coupled with dislocations and underwent a compressive strain. These results suggest that the thickness of ferroelastic domain walls highly depends on their atomic environments. This study can help us to understand the past debatable experimental results and provide further insights into control of domain wall thickness via strain engineering for their possible applications in nanoelectronics. Image, graphical abstract [ABSTRACT FROM AUTHOR]

The influence of Cr on the interfacial bonding and erosion-corrosion resistance of ZrO 2 -Al 2 O 3 particles reinforced high chromium white cast irons based (ZTA P /Fe) composites were systematically investigated. The Cr coatings on the surface of ZTA particle (ZTA P) ceramics were fabricated by multi-arc ion plating. The results indicated that a uniform and continuous Cr coating was tightly adhered with ZTA ceramic substrate. The thickness and grain size of the Cr coating could be effectively controlled by regulating the deposition parameters. The grain size of Cr coating increased with deposition time. The ZTA P /Fe composites assisted without (N1) and with (N2) Cr coating were prepared via infiltration casting. The addition of Cr coating obtained a smooth and tight interface, attributed to the improvement of the wettability between ZTA ceramic and high chromium white cast irons matrix (Cr15). Moreover, the erosion-corrosion resistance property of the Cr coated ZTA P /Fe composites (N2) improved up to 44% compared with bare-ZTA P /Fe composites (N1) due to their interfacial enhancement action. Meanwhile, the interfacial layer of the N2 composites had a low roughness after erosion-corrosion. • The continuous Cr coating could be obtained by multi-arc ion plating. • A Cr15-based composites reinforced with Cr-coated ZTA P ceramic was fabricated. • Cr coating could improve the interfacial properties of ZTA P /Fe composites. • The effect of Cr on erosion-corrosion resistance of ZTA P /Fe composites were investigated. [ABSTRACT FROM AUTHOR]

In this work, the nickel-cobalt layer was used as a medium to improve the interfacial bonding of ZrO 2 –Al 2 O 3 particles (ZTA P) reinforced high manganese steel-based composites. The nickel-cobalt layers on the surface of ZTA P ceramics are prepared by electroless deposition in the sulfate solutions. The formation mechanism, morphology evolution and elemental composition of the NiCo coating were investigated by varying the plating temperature, plating time and sulfate concentration. The NiCo grain size increases, and the coating thickness increases and then decreases with CoSiO 4 concentration. A dense and uniform nickel-cobalt coating could be obtained after plating with 25 g/L CoSiO 4 at 80 °C for 10 h. NiCo coated ZTA P ceramics reinforced high manganese steel matrix composites were fabricated using non-pressure casting infiltration. The results showed that NiCo improves the bonding property of composites causing a tighter and cleaner interface compared with severe defects of cracks, delaminations and holes on the interface of composites without NiCo coating. The effects of NiCo coating on tribological properties of the composites were clarified by the three-body abrasive wear. The superior interfacial bonding of composites assisted with NiCo coating exhibited excellent abrasive wear resistance, which increases by 230%. • A nickel-cobalt coating on the ZTA P surface was prepared utilizing electroless deposition. • The deposition mechanism of NiCo coating on the ZTA ceramics was clarified. • NiCo coating could effectively improve the interface bonding property of composite. • The NiCo coating was a key factor in enhance abrasive wear resistance of composites. [ABSTRACT FROM AUTHOR]

To investigate the erosive wear-corrosion behavior of ZTA P ceramic reinforced high chromium cast iron matrix composites in two types of sand at various rotational speeds, the ZTA P /Fe composites were fabricated. The interface characteristics, erosion wear-corrosion and erosive wear mechanism have been investigated in a slurry condition at various erosion rotational speeds. The chemical composition of the matrix material was determined using a spark spectrometer. SEM, TEM, 3D laser scanning microscope and AFM were used to analyze the microstructure characteristics and worn surface morphology of the composites. Furthermore, the wear loss rate and relative erosive wear resistance of ZTA P /Fe composites and Cr15 standard specimen measurements were conducted. The results showed that the interface between the ZTA P ceramics and the Cr15 matrix exhibits a continuous transition layer without visible defects and close contacts. In the case of SiO 2 and SiC abrasive sand, the wear rate of ZTA P /Fe composites and Cr15 standard specimens increases with erosion time. The wear rate of ZTA P /Fe against SiO 2 sand is lower than that of against SiC sand. ZTA P /Fe composites was found to exhibit a better corrosion resistance property than that of Cr15 standard specimens. [Display omitted] • A continuous transition layer and tightly contacts without visible defects, ensuring an excellent interfacial bond. • The addition of the ZTA ceramics can improve the corrosion resistance performance of high chromium cast iron. • For SiO 2 sands, the relative erosive wear resistance of the composites reaches 1.68–2.43 times the reference Cr15matrix. • For SiO 2 sand, the erosive wear mechanism of composites is the fatigue wear and corrosion of the iron matrix. [ABSTRACT FROM AUTHOR]

Abstract: The behavior of several landscape pattern metrics were tested against various pattern scenarios generated by neutral landscape models, including number of classes, scale-map extent, scale-resolution, class proportion, aggregation level—RULE, and aggregation level—SimMap. The results demonstrate that most of the metrics are sensitive to certain pattern scenarios, yet are not sensitive to others; therefore, none of them is appropriate for all aspects of a landscape pattern. Despite these limitations, some of these metrics are recommended for future use, which include total number of patches, average patch size, total edge density, double-logged fractal, contagion, and aggregation index. Special attention should be paid to the relationships between metric values and ecological processes rather than the numbers themselves. [Copyright &y& Elsevier]

Abstract: Low antigenicity or development of tolerance is believed to be a major contributor to the escape of malignant tumors from immune surveillance of the host. However, anti-tumor responses can be elicited by concomitant immunization of poorly antigenic tumor cells with homologous xenogeneic proteins as ‘altered self’ proteins. In our study, anti-tumor, but not anti-xenogeneic antigen, immune responses were generated after transduction of the gene coding for a G-protein coupled human formyl peptide receptor like-1 (FPRL1) into a mouse C26 colon cancer cell line. C26 cells transfected with FPRL1 gene exhibited markedly reduced tumorigenicity in syngeneic mice, in association with the appearance of high levels of antibody activity reacting with both FPRL1 containing and wild type C26 cells. The anti-tumor responses required the participation of CD4+ T lymphocytes, since no tumor rejection was observed in nude mice or in syngeneic mice depleted of CD4+ T cells. Furthermore, mice primed with FPRL1 transfected C26 cells were resistant to subsequent challenge by wild type C26 cells. These results indicate that the presence of human FPRL1 is capable of triggering specific anti-tumor host immune responses against poorly antigenic mouse tumor cells. [Copyright &y& Elsevier]

The Sanjiang Plain has the largest marsh wetland area in China. Since the 1950s its size has declined due to land development, between 1986 and 2016 nearly 6072 km2 (57.5% of the area) was lost due to farm land expansion. Since the "Wetland for Grain" project in 2003, efforts have been made to improve marsh area for animal habitat and ecological protection. A key management concern is prioritizing areas for wetland restoration in scientific planning and polices making. In this study, the natural wetland restoration potentials were evaluated based on land-use change trajectory, seed bank viability and watershed sustainability and restorability. The annual land use maps from 1986 to 2016 were reconstructed using CLUE-S model with land use maps in 1995, 2000, 2005, 2010 and 2016, which were interpreted from Landsat TM/ETM images. Seed bank viability was determined by field sampling in wetland and farm land with different reclamation years and germination in lab. Sub-catchment was chosen as sustainability analysis unit, which was quantified by the impacts of wetland on peak flow reduction. The watershed restorability was performed with the factors of wetland degradation degree, seed bank viability, and the percentage of wetland to watershed area (PWW) with different restoration years. The results indicated that reclaimed wetland with a time since last development (TLD) of <15 years had a higher recovery potential and accounted for 39.2% of the lost wetland. Seventeen sub-catchments with a total area of 2177 km2 of farmland could be planned for restoration, which could support more than half of the sub-catchments in the study area. Priority areas were identified for short-, mid- and long-term restoration planning. The results can support the scientific planning demands of various restoration goals in the study area, and provide a new method for wetland restoration. Unlabelled Image • Potential wetland restoration areas were identified by the seed bank viability and land use model. • The annual wetland degradation trajectory was determined for 1986–2016 using of CLUE-S model. • The restoration potential of farmland back to wetland decreases as the time since agricultural development increases. • The percent of wetland area to watershed area (PWW) could act as an indicator of watershed ecological sustainability. [ABSTRACT FROM AUTHOR]