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The development of a regeneration agent is one of the key technologies for pavement regeneration and one of the methods to reduce carbon emissions in the transportation field, so it is very necessary to develop a regeneration agent. Based on the composition of asphalt and rejuvenator components, the optimal dosing of extraction oil, plasticizer dioctyl phthalate (DOP), and hydrogenated (carbon 9) C9 petroleum resin was determined by the response surface method, and the suitable dosing of the anti-aging agent was also designed to optimize the orthogonal experiment to prepare the ZJ-I (Zenith Yummy-Invent) rejuvenator with good overall performance. On the basis of the ZJ-I rejuvenator, dynamic shear rheology (DSR), bending beam rheometery (BBR), Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), and contact angle experiments were used to investigate the effects of the ZJ-I rejuvenator dosing on the high- and low-temperature rheology, chemical structure, surface microscopic morphology, and adhesion between asphalt and aggregate of aged asphalt and to explore the regeneration effect and regeneration mechanism of the ZJ-I rejuvenator. The results showed that the ZJ-I rejuvenator formulated with 83.6% extracted oil, 15% plasticizer DOP, 1.4% hydrogenated petroleum resin, 0.6% antioxidant, and 0.4% light stabilizer has the best regeneration effect, and its optimal dosing is 7% aging degree. It can also improve the adhesion performance of asphalt and aggregate.

The Sentinel-2A satellite having embedded advantage of red edge spectral bands offers multispectral imageries with improved spatial, spectral and temporal resolutions as compared to the other contemporary satellites providing medium resolution data. Our study was aimed at exploring the potential of Sentinel-2A imagery to estimate Above Ground Biomass (AGB) of Subtropical Pine Forest in Pakistan administered Kashmir. We developed an AGB predictive model using field inventory and Sentinel 2A based spectral and textural parameters along with topographic features derived from ALOS Digital Elevation Model (DEM). Field inventory data was collected from 108 randomly distributed plots (0.l ha each) across the study area. The stepwise linear regression method was employed to investigate the potential relationship between field data and corresponding satellite data. Biomass and carbon mapping of the study area was carried out through established AGB estimation model with R (0.86), R2 (0.74), adjusted R2 (0.72) and RMSE value of 33 t/ha. Our results showed that first order textures (mean, standard deviation and variance) significantly contributed in AGB predictive modeling while only one spectral band ratio made contribution from spectral domain. Our study leads to the conclusion that Sentinel-2A optical data is a potential source for AGB estimation in subtropical pine forest of the area of interest with added benefit of its free of cost availability, higher quality data and long-term continuity that can be utilized for biomass carbon distribution mapping in the resource constraint study area for sustainable forest management.

The Niviventer fulvescens species complex (NFSC), a group of abundant and taxonomically ambiguous rodent taxa, is distributed from Southeast Asia to south-eastern China. We combined molecular and morphological datasets to clarify the species composition and variation of the NFSC. Our phylogenetic analyses, using molecular data, recovered eight genetic lineages in the NFSC, including a novel, distinct lineage from Jilong, Tibet, China, which is described as a new species, N. fengi sp. nov. The species status of N. fengi is supported by a species delimitation analysis, and it is morphologically distinguished from other members of the NFSC by its greyish dorsal fur, soft hairs covering the whole body and a hairy tail. NFSC species bearing well-developed spines are found at lower elevations. A comprehensive taxonomic revision of the NFSC within China is provided, represented by five species: N. cremoriventer, N. fulvescens, N. huang, N. mekongis comb. nov. and N. fengi. A further study of this species complex, including samples from Southeast Asia, is needed.

The Yellow River delta (YRD) is regarded as one of the most rapid sedimentation deltas in the worldwide and the youngest land in China. Existing studies more focused on evolutions of river mouth region, thus provided limited knowledge on the evolution of the entire YRD and its corresponding trajectories of shrinkage and expansion. Here, we used 1984–2018 Landsat images and the change detection analysis algorithm to track annual area change trajectories of present YRD with the help of Google Earth Engine cloud platform. Results showed that entire YRD area documented a significantly shrinking trend with slope of –18.5 km2/decade ( p p p

Understanding the change of river islands is essential for water conservancy construction, channel navigation safety, and industrial/agricultural production. Yangtze River is the largest river in China; however, there are few long-term monitoring results on the changes of Yangtze River islands. To fill this gap, Landsat data available on the Google Earth Engine (GEE) were used to obtain the annual changes of the Yangtze River islands located from the lower reaches of the Three Gorges Dam (TGD) to the Yangtze River delta during 1986-2017. Moreover, we focused on the changes of those islands before and after the construction of the TGD. Annual areas of all river islands were calculated and spatial-temporal pattern of Yangtze River islands were analyzed. Our satellite observation results show continuous expansions of Yangtze River islands after the construction of the TGD in 2003. For the total 138 river islands, in three stages: before 2003, after 2003 and in the 32-year study period, 68, 118, and 124 river islands showed increasing trends, with the net increase of 286.47 km2, 417.49 km2, and 665.62 km2. For the total 92 river island groups (138 islands), percentages of river island expansion are 41.30% (before 2003), 80.43% (after 2003) and 88.04% (1986-2017). Moreover, we found 10 newly developed river islands, with a net expansion of 87.42 km2 and an expansion rate of 2.73 km2/year. The significant decrease (2-4 m) in water level before and after the TGD might be the main factor that results in the observed expansion of Yangtze islands downstream the TGD. We also highlighted the importance of using all available Landsat imagery for tracking the changes of river islands. Our satellite-derived dataset provide reference data for the land use planning and environmental protection in the Yangtze River drainage basin.

Background. The small molecule inhibitor XAV939 could inhibit the proliferation and promote the apoptosis of non-small cell lung cancer (NSCLC) cells. This study was conducted to identify the key circular RNAs (circRNAs) and microRNAs (miRNAs) in XAV939-treated NSCLC cells. Methods. After grouping, the NCL-H1299 cells in the treatment group were treated by 10 μM XAV939 for 12 h. RNA-sequencing was performed, and then the differentially expressed circRNAs (DE-circRNAs) were analyzed by the edgeR package. Using the clusterprofiler package, enrichment analysis for the hosting genes of the DE-circRNAs was performed. Using Cytoscape software, the miRNA-circRNA regulatory network was built for the disease-associated miRNAs and the DE-circRNAs. The DE-circRNAs that could translate into proteins were predicted using circBank database and IRESfinder tool. Finally, the transcription factor (TF)-circRNA regulatory network was built by Cytoscape software. In addition, A549 and HCC-827 cell treatment with XAV939 were used to verify the relative expression levels of key DE-circRNAs. Results. There were 106 DE-circRNAs (including 61 upregulated circRNAs and 45 downregulated circRNAs) between treatment and control groups. Enrichment analysis for the hosting genes of the DE-circRNAs showed that ATF2 was enriched in the TNF signaling pathway. Disease association analysis indicated that 8 circRNAs (including circ_MDM2_000139, circ_ATF2_001418, circ_CDC25C_002079, and circ_BIRC6_001271) were correlated with NSCLC. In the miRNA-circRNA regulatory network, let-7 family members⟶circ_MDM2_000139, miR-16-5p/miR-134-5p⟶circ_ATF2_001418, miR-133b⟶circ_BIRC6_001271, and miR-221-3p/miR-222-3p⟶circ_CDC25C_002079 regulatory pairs were involved. A total of 47 DE-circRNAs could translate into proteins. Additionally, circ_MDM2_000139 was targeted by the TF POLR2A. The verification test showed that the relative expression levels of circ_MDM2_000139, circ_CDC25C_002079, circ_ATF2_001418, and circ_DICER1_000834 in A549 and HCC-827 cell treatment with XAV939 were downregulated comparing with the control. Conclusions. Let-7 family members and POLR2A targeting circ_MDM2_000139, miR-16-5p/miR-134-5p targeting circ_ATF2_001418, miR-133b targeting circ_BIRC6_001271, and miR-221-3p/miR-222-3p targeting circ_CDC25C_002079 might be related to the mechanism in the treatment of NSCLC by XAV939.

The mountainous and hilly region plays an important role in ecological safety and production in China. However, recent studies have poorly characterized the parallel structure of land use in the valleys of the mountainous and hilly region using topographic factors (e.g. elevation, slope, aspect). Here, the loess hilly region of northern Shaanxi Province is used as a representative case area to analyze the vertical distribution pattern of land-use conversion using the relative elevation concept and the HAND index. The differences in the vertical structure of land-use conversion between absolute elevation and relative elevation were compared. We found that the classifications of absolute and relative elevation had similar proportions of each relative elevation grade in each absolute elevation grade. Cropland, woodland, and grassland were distributed evenly in each grade of absolute/relative elevation, while water body, built-up land and unused land were more likely to spread in low grades of relative elevation than those of absolute elevation. The land-use conversion (i.e. loss of cropland and gain in woodland and built-up land) showed an apparently stepped distribution with relative elevation classification, suitable for revealing vertical distributions of land-use conversion in the loess hilly region. Cropland transformed to woodland was mainly distributed in high grade of relative elevation, decreasing with a decrease in grades, while built-up land transformed from cropland and grassland was mainly distributed in low grade of relative elevation, decreasing with increases in grades. The grade of relative elevation where cropland transformed to woodland descended with the implementation of the Grain for Green Project. Our results suggest that it is better to analyze the vertical distribution of land-use conversion with relative elevation classification in hilly regions.

Spatial heterogeneity in vegetation greenness (VG) can influence earth surface process and resource ecology. However, its long-term change and driving forces remain poorly understood. In this study, MODIS enhanced vegetation index (EVI) data was used to examine the change in spatial heterogeneity in VG and its relationships with vegetation greening in mainland China during 2000–2017. Moving window standard deviation and range of growing season mean EVI (GSEVI) were used as proxies for spatial heterogeneity in VG. It was found that moving window standard deviation of GSEVI increased significantly over 33.8% to 53.7% of mainland China during 2000–2017, while it decreased significantly over less than 5% of mainland China. The results of moving window range of GSEVI were similar to moving window standard deviation of GSEVI. These may be explained by: (1) increased standard deviation and range of GSEVI accompanied by increased GSEVI value; and (2) faster greening speed in dense than in sparse vegetated areas. Additionally, the increased spatial heterogeneity in VG means the increased difference in VG between arid and humid regions, and between urban cores (UCs) and rural areas. These may primarily be attributed to slower greening speed in arid than in humid regions, and in UCs than in rural areas. Thus some benefits from vegetation greening may be much less in arid than in humid regions, and in UCs than in rural areas. Overall, this study analyzed an interesting phenomenon that vegetation greening may increase spatial heterogeneity in VG, which has a series of implications for environment and human activities.

Vertically integrated atmospheric water vapor (VIWV) over the Indo-Pacific warm pool (IPWP) indirectly affects terrestrial vegetation growth (TVG) patterns through atmospheric water vapor transmission. However, their linkages and mechanisms are poorly understood. This study intends to understand the contributions of VIWVIPWP to TVG and the mechanisms by which VIWVIPWP impacts TVG. Combining monthly SST, VIWV, and NDVI data from 1982 to 2015, the linkage between VIWVIPWP and NDVI is investigated during April–June (AMJ). A strong correlation between VIWVIPWP and NDVI suggests that VIWVIPWP is an important factor affecting TVG. A composite analysis of VIWVIPWP anomalies and their relation to NDVI patterns shows that VIWVIPWP positively influences the NDVI of 68.1% of global green land during high-VIWVIPWP years but negatively influences 74.7% in low years. Corresponding to these results, during high-VIWVIPWP years, the warm and humid terrestrial climate conditions improved TVG by 9% and 2% in the Northern and Southern Hemispheres, respectively, but cold and dry conditions inhibited TVG for both hemispheres during the low years. Additionally, strong spatial correlations between VIWVIPWP and precipitation imply that VIWVIPWP affects the spatial–temporal pattern of precipitation. There is a stronger interaction between the Pacific north–south ridge and the two land troughs during high-VIWVIPWP years than during low-VIWVIPWP years. The zonally averaged wind at 850 hPa and VIWV results indicate that, during high-VIWVIPWP years, the enhanced wind from the ocean brings more atmospheric water vapor to land, increasing the probability of precipitation and resulting in moist climate conditions that promote AMJ vegetation growth. In brief, VIWVIPWP indirectly induces vegetation growth by affecting the distributions of terrestrial VIWV and precipitation.

Lung cancer belongs to a leading popular and malignant cancer around the world. However, the root mechanism underlying lung cancer progression remains unclear. Recently, long noncoding RNA (lncRNA) has been identified as important for tumorigenesis. LncRNA MNX1-AS1 is proven to regulate colon adenocarcinoma, cervical cancer, glioblastoma, and ovarian cancer. Whether MNX1-AS1 participates in lung cancer needs investigation. In our research, we found that MNX1-AS1 was dramatically upregulated in lung cancer. MNX1-AS1 upregulation indicated poor prognosis in lung cancer patients. Functionally, MNX1-AS1 promoted lung cancer progression through regulating proliferation, migration, and invasion. Mechanistically, MNX1-AS1 was found to locate in the cytoplasm and interact with miR-527. Through inhibiting miR-527 availability, MNX1-AS1 facilitated BRF2 expression. Restoration of BRF2 rescued defects of proliferation, migration, and invasion caused by MNX1-AS1 knockdown. Taken together, our study found a novel signaling pathway, namely MNX1-AS1/miR-527/BRF2 axis, involved in lung cancer progression.

Climate warming and its corresponding impacts on agriculture system increasingly attach great attentions. Earlier studies more concerned the impacts of the cultivated area expansion under climate change. Yet limited knowledge is about the impacts of climate warming on the cropping index change with the shifts of cropping system border. In this study, we used climatic data (1961-2015) to firstly investigate impacts of warming temperature on potential cropping system border expansion of China, and further used agricultural statistical data and satellite-based land use data to analyze the response of current land system to potential cropping system border expansion. Results of this study indicated that obviously advanced SDT10 and prolonged EDT10 contributed to the 88.4% regions of increased AAT10 at the past half century. Moreover, the northward expansion of the suitable cultivated areas in different cropping systems provided advantages for potential multiple cropping index (PMCI) improvement. Unfortunately, this study found that a significantly declined multiple cropping index (MCI) was observed in the peri-urban regions and the provinces with large out-migration of agriculture labor. The evidently increased MCI was only greatly observed in Xinjiang province. Besides, the potential increment of multiple cropping index (PIMCI) for different cropping system border expansion regions presented a rising trend and reached 53.6% in 2015 due to warming climate. Particularly, the significantly increased PIMCI was observed in the Loess Plateau, the Inner Mongolia, the Middle-lower Yangtze Plain, Northeast China Plain, Southern China and Beijing-Tianjin-Hebei Metropolitan Region. However, the response of current land system to the changes of PMCI and PIMCI was not timely. Based on the findings of our study, some potential agriculture development strategies were suggested by comprehensively considering regional natural conditions, agricultural production conditions and socioeconomic conditions. We hope these findings of this study could provide some valuable information for agricultural development policy decision-making.

Poverty restricts rural sustainable development and urban&ndash, rural integration. Agricultural development is an engine of rural economic development and poverty elimination. Agricultural structure adjustment and rural poverty alleviation in Yulin City from the agro-pastoral transition zone of Northern China were studied using statistical data. Our results showed that the rural poverty ratio in Yulin was 7.70% in 2017, with clearly higher trends in southeast regions and lower trends in northeast regions. Northern Yulin had a lower proportion of primary industry to gross domestic production and ratio of agriculture to animal husbandry than southern Yulin. The agricultural structure variability index and agricultural specialization index have changed little, while the actual growth rate of the rural per capita net income has dramatically declined in the last decade. The rural poverty ratio was positively correlated with proportion of primary industry and ratio of agriculture to animal husbandry. These results suggest that a reduced proportion of primary industry and animal husbandry development will promote rural poverty alleviation and future rural revitalization.

Wheat vegetative growth, defined as the stage from green-up date to heading date (STAGE), is a crucial phrase, which largely affects crop yield. Previous some studies mainly focused on site-based changes of STAGE. However, there are few studies concerning large-scale changes of STAGE, which limits our understanding of regional changes of STAGE in response to climate change. Here, we introduced robust satellite-based phenological algorithms as well as third-generation global inventory modeling and mapping studies normalized difference vegetation index for the period of 1982–2015 to spatially derive winter wheat green-up date, heading date, and STAGE over croplands of the North China Plain (NCP). Changes of STAGE and their response to climate change were then investigated. Results showed that a strong predicted ability of introduced heading date algorithm was observed with r of 0.88 ( p R 2 = 0.11, p = 0.06). Stage of 23.4% cropland pixels performed significantly lengthened trends ( p r = 0.59, p < 0.01). This study highlights important roles of remote sensing data and satellite-based phenological algorithms for regional crop growth monitoring and management.

Separating anthropogenic contributions from observed vegetation change is helpful for improving our understanding of the effects of human activities on regional ecosystems. In this study, using 1982–2015 GIMMS3g normal difference vegetation index (observed NDVI), monthly climatic variables and land use data, we investigated anthropogenic contributions on vegetation change in the farming-pastoral ecotone of northern China (FPEN). Specifically, given that large-area ecological engineering was practiced since 1999 and large-area land use changes were recorded after 2000, we assumed that human activities only had little impact before 1999. Based on this assumption, we developed a climate-based NDVI model (also termed as TPR-based NDVI model) by using 1982–1999 observed NDVI and assembled monthly precipitation, temperature and solar radiation. Subsequently, the TPR-based NDVI model as well as the residual analysis method were used to separate anthropogenic contributions from observed NDVI in the period of 2000–2015. Results showed that most FPEN performed a greening trend for the period of 1982–2015. Yet a browning trend was also found in central and northern FPEN. The browning trend was largely related to changes of observed NDVI after 2000. Spatial statistics for the best related climatic variable with observed NDVI displayed that temperature, precipitation and solar radiation separately accounted for 42.45%, 31.05% and 26.50% of FPEN, implying their similar importance for vegetation growth in space. Importantly, this study found that anthropogenic contributions dominated trends of observed NDVI over FPEN. Human activities significantly increased NDVI in western and southeastern FPEN (p

Studying the shifts of vegetation phenology and the response of vegetation phenology to climate change helps to understand the dynamics of future ecosystems. However, since previous studies mostly focused on temperate ecosystems, much less is known about the biogeographic phenological shifts in sub-tropical regions, which have abundant biodiversity. The Yangtze River Basin (YRB) is located in the subtropical region of China and has abundant natural resources, a large population, and rapid economic development. Studying the variation characteristics of phenology and its responses to recent climate changes in YRB are important for understanding the impact of regional climate on subtropical ecosystems. In this study, we extracted the phenological parameters using Global Inventory Modeling and Mapping Studies (GIMMS) data to investigate the spatial and temporal variations of vegetation phenology across YRB during 1982–2015 and to examine how vegetation phenology responds to climate within different ecological zones. The results revealed that the start of growing season (SOS) was significantly advanced by 0.2 days/year (p

Alpine vegetation plays a crucial role in global carbon cycle. Snow cover is an essential component of alpine land cover and shows high sensitivity to climate change. The Tibetan Plateau (TP) has a typical alpine vegetation ecosystem and is rich of snow resources. With global warming, the snow of the TP has undergone significant changes that will inevitably affect the growth of alpine vegetation, but observed evidence of such interaction is limited. In particular, a comprehensive understanding of the responses of alpine vegetation growth to snow cover variability is still not well characterized on TP region. To investigate this, we calculated three indicators, the start (SOS) and length (LOS) of growing season, and the maximum of normalized difference vegetation index (NDVImax) as proxies of vegetation growth dynamics from the Moderate Resolution Imaging Spectroradiometer (MODIS) data for 2000–2015. Snow cover duration (SCD) and melt (SCM) dates were also extracted during the same time frame from the combination of MODIS and the Interactive Multi-sensor Snow and Ice Mapping System (IMS) data. We found that the snow cover phenology had a strong control on alpine vegetation growth dynamics. Furthermore, the responses of SOS, LOS and NDVImax to snow cover phenology varied among different biomes, eco-geographical zones, and temperature and precipitation gradients. The alpine steppes showed a much stronger negative correlation between SOS and SCD, and also a more evidently positive relationship between LOS and SCD than other types, indicating a longer SCD would lead to an earlier SOS and longer LOS. Most areas showed positive correlation between SOS and SCM, while a contrary response was also found in the warm but drier areas. Both SCD and SCM showed positive correlations with NDVImax, but the relationship became weaker with the increase of precipitation. Our findings provided strong evidence between vegetation growth and snow cover phenology, and changes in snow cover should be also considered when analyzing alpine vegetation growth dynamics in future.

ERA-Interim has been widely considered as a valid proxy for observations at global and regional scales. However, the verifications of ERA-Interim precipitation and temperature in mainland China have been rarely conducted, especially in the spatial and long-term performances. Therefore, in this study, we employed the interpolated ground station (STA) data to evaluate the spatial and temporal patterns and trends of ERA-Interim precipitation and temperature during 1980–2012. The results showed that relatively weaker performances were observed in ERA-Interim precipitation, with the skill score (S index) ranging from 0.41 to 0.50. Interannual ERA-Interim precipitation presented comparable trends with STA precipitation at the annual and seasonal scales. Spatial patterns of empirical orthogonal function (EOF) modes and corresponding principal components were evidently different between annual ERA-Interim and STA precipitation. For temperature, annual and seasonal patterns of ERA-Interim data were in good consistency with those of STA over China with the S index ranging from 0.59 to 0.70. Yet interannual STA temperature recorded stronger warming trends (from 0.37 K decade−1 of wintertime to 0.53 K decade−1 of springtime) at the annual and seasonal scales compared to corresponding periods for ERA-Interim temperature (from 0.03 K decade−1 of wintertime to 0.25 K decade−1 of summertime). Overall, ERA-Interim precipitation and temperature had good agreement with STA data in east China with lower elevation (

Frequent drought events are threatening regional/global food security. However, current models for predicting crop yield loss suffered from drought threat is still limited. In this study, seven drought indices were employed to develop an aggregate drought index (ADI) to quantify the drought effect on crop yield in the North China Plain (NCP). Based on time-series and panel regression models, relationships between climatic yield anomalies of winter wheat (ΔY) and ADI values before sowing of winter wheat and during its growth were investigated. Results showed that ADI assembled the advantages of drought indices and reasonably described the range, severity and duration of drought events. During the study period, trends of annual ADI displayed remarkable spatial heterogeneity in the growth stages. Increasing trends of ADI over 0.005/year were found in most areas of NCP at STAGE 1 (from July to September in last year). At STAGE 4 (from grain-filling to maturation), increasing and decreasing trends were observed in northern and southern NCP, respectively. Based on panel model, ADI in the four stages could predict about 20% variations of ΔY in areas with high irrigation supplies. Meanwhile, more than 40% variations of ΔY may be predicted in eastern NCP with low irrigation supplies. The study highlights the importance of integrating drought information and irrigation for assessment of winter wheat yield variations.

The information on land surface phenology (LSP) was extracted from remote sensing data in many studies. However, few studies have evaluated the impacts of satellite products with different spatial resolutions on LSP extraction over regions with a heterogeneous topography. To bridge this knowledge gap, this study took the Loess Plateau as an example region and employed four types of satellite data with different spatial resolutions (250, 500, and 1000 m MODIS NDVI during the period 2001–2020 and ~10 km GIMMS3g during the period 1982–2015) to investigate the LSP changes that took place. We used the correlation coefficient (r) and root mean square error (RMSE) to evaluate the performances of various satellite products and further analyzed the applicability of the four satellite products. Our results showed that the MODIS-based start of the growing season (SOS) and end of the growing season (EOS) were highly correlated with the ground-observed data with r values of 0.82 and 0.79, respectively (p < 0.01), while the GIMMS3g-based phenology signal performed badly (r < 0.50 and p > 0.05). Spatially, the LSP that was derived from the MODIS products produced more reasonable spatial distributions. The inter-annual averaged MODIS SOS and EOS presented overall advanced and delayed trends during the period 2001–2020, respectively. More than two-thirds of the SOS advances and EOS delays occurred in grasslands, which determined the overall phenological changes across the entire Loess Plateau. However, both inter-annual trends of SOS and EOS derived from the GIMMS3g data were opposite to those seen in the MODIS results. There were no significant differences among the three MODIS datasets (250, 500, and 1000 m) with regard to a bias lower than 2 days, RMSE lower than 1 day, and correlation coefficient greater than 0.95 (p < 0.01). Furthermore, it was found that the phenology that was derived from the data with a 1000 m spatial resolution in the heterogeneous topography regions was feasible. Yet, in forest ecosystems and areas with an accumulated temperature ≥10 °C, the differences in phenological phase between the MODIS products could be amplified.