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Ningxia is an important agriculture-pastoral area in China. Research on the temporal and spatial variations of net primary productivity (NPP) in this area and its driving factors would help understand the trends and leading factors of NPP variations, and reveal vegetation restoration status and causes. Based on the NPP data of MODIS, we used Theil-Sen Median trend analysis, correlation analysis, overlay analysis and other methods to analyze the spatiotemporal variations and driving factors of NPP in Ningxia. The results showed that NPP of Ningxia vegetation showed a fluctuating upward trend during 2000-2019, with a linear growth rate of 5.46 g C·m -2 ·a -1 . The NPP presented a spatial characteristics of "two high and two low", with the highest in the southern mountain area, followed by the Yellow River irrigation area, and the lowest in the hilly area of the central arid zone and Helan Mountain. 84.2% of the NPP in the study area was under significant restoration, mainly distributed in the central and southern mountainous and hilly areas. The NPP varied significantly with altitude and was significantly affected by the terrain. NPP center of gravity had generally moved to the south, with the increase and growth rate of NPP of vegetation in the south being greater than that in the north. The annual precipitation in Ningxia had shown an increasing trend, while the average annual temperature had slightly decreased. The NPP was significantly affec-ted by precipitation ( R 2 =0.291), whereas the correlation between mean annual temperature and NPP was weak. 96.9% of the study area was at a state of vegetation restoration, which was promoted by both climate change and human activities.

Lead (Pb) as a hazardous air pollutant has raised widespread concerns due to its adverse and toxic effects on the ecological environment and human health. Here we integrated the multi-regional input-output (MRIO) model and an atmospheric transport model to examine regional environmental inequality (REI) index induced by Pb emission transfers, and to evaluate the impacts of interprovincial trade on regional atmospheric Pb concentrations and dry deposition fluxes in China in 2012. In 2012, approximately 57.4% ~ 72.6% of Pb emissions in well-developed eastern regions (Beijing-Tianjin, Yangtze River Delta (YRD)) and the southern seaboard of China were embodied in other regions in China subject to the demands from these well-developed regions to industrial products and services. Our results, based on the net virtual flows of Pb emission and value-added, indicate that most provinces in the eastern seaboard of China outsource Pb emission and benefit from the interprovincial trade by reducing their Pb emissions. REI indexes show that the well-developed Guangdong province outsources its Pb emission but has low economic gains. Many less-developed provinces in central China enhance virtual Pb emission inflow but have high economic gains. Whereas, inland provinces in western China not only experience Pb emission increase, but also suffer from indirect economic loss due to trade with well-developed provinces to meet their increasing demands to Pb emission abundant industrial products from these provinces in eastern China which are mostly provided by less-developed but energy and mineral product abundant provinces in western China. For example, the province pair with highest REI index was Jiangsu-Inner Mongolia (REI = 2.47), which revealed that Jiangsu was the largest beneficiary which exported 37.2 t of net Pb emission and gained value-added of 521.4 billion RMB through trade with Inner Mongolia which suffered from both virtual Pb inflow and economic loss in 2012. As a result of interprovincial trade, Pb dry deposition in central and eastern China was decreased but increased in western China. Overall, interprovincial trade reduced 17.6% of atmospheric Pb dry deposition in China., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Reasonable rotation is of great significance to grassland management. We examined the distribution characteristics, stability, organic carbon content and contribution rate of 0-30 cm soil aggregates in the forbidding grazing, continuous grazing, and rotation in the two-paddock, four-paddock and six-paddock rotational districts in a desert steppe in Ningxia. The results showed that except for the forbidding grazing grassland that was dominated by mechanically stable large aggrega-tes, other water-stable aggregates were mainly composed of microaggregates. Increasing the rotational grazing zoning was conducive to maintain the content of water-stable aggregates in the surface soil and increase the content of large aggregates. The mechanical stability aggregate fractal dimension was the largest in continuous grazing, increased the fractal dimension of the rotation and shepherd partition to reduce the trend, but the fractal dimension of water-stable aggregates did not change. The average weight diameter (MWD) and geometric mean diameter (GMD) of the aggregates were the largest in the pastoral grassland and increased with the increases of the rotational grassland partition. MWD and GMD were negatively correlated with the microaggregate content. The organic carbon content in water-stable large aggregate was higher in the six-paddock rotational district and forbidding grazing, and the two-paddock rotational grazing and continuous grazing were lower. The contribution rate of micro-aggregates organic carbon to soil organic carbon content was higher in this region. In the 0-20 cm soil layer, the contribution rate of organic carbon in large aggregates increased with the increases of rotation. Considering the characteristics of soil aggregates and their organic carbon, the rotation of six-paddock was the most suitable method for rotational grazing in the desert steppe of the study area.

Objective: To investigate the characters and changes of peripheral white blood cells and lymphocyte subsets of patients with pandemic influenza A virus (H1N1) infection and to provide evidences for diagnosis, treatment and prognosis of influenza A (H1N1) infection., Methods: Peripheral white blood cell parameters and the percentages of lymphocyte subsets in acute and recovery phases of 59 cases of influenza A virus (H1N1) infectious patients (42 mild cases and 17 severe cases) were investigated and analyzed, and compared respectively with those of 43 cases of healthy adults as control (HC) and 24 cases of general influenza A virus (no-H1N1) infectious using whole blood cell analysis and flow cytometry., Results: Peripheral white blood cell counts of mild cases decreased greatly but those of severe cases did not decrease significantly; the neutrophils of severe cases increased significantly in acute phase; similar to general influenza A virus (no-H1N1) infectious, the peripheral lymphocytes, CD3, CD4, CD8 and B cells of all patients with influenza A virus (H1N1) infection decreased greatly in acute phase and quickly recovered in recovery phase; NK and NKT cells absolute counts of severe cases decreased significantly in acute phase, and the decreasing extent of which were more than 20%., Conclusion: There were similar characteristics of change in peripheral white blood cells and lymphocyte subsets between patients with pandemic influenza A virus (H1N1) infection and general pandemic A virus (No-H1N1); the great decrease of NK and NKT cells absolute counts may suggest the severe tendency of diseases.