[Nonlinear Variations in PM2. 5 Concentration in the Three Major Urban Agglomerations in China].

ITA and Beast methods were used to quantitatively analyze the nonlinear process of a PM2.5 concentration time series based on the PM2.5 concentration data of the three major urban agglomerations in China. The results showed that： ① the degree of the PM2.5 pollution in the three major urban agglomerations had decreased， and the high-concentration areas had noticeably shrunk. The degree of spatial polarization of PM2.5 concentration was reduced， and the spatial difference was narrowed. The PM2.5 concentration in most areas showed downward trends， but the degree of change was not the same. Compared with the YRD and PRD， the concentration of PM2.5 in the BTH was still at a relatively high level. ② The concentration of PM2.5 in the three major urban agglomerations had seasonal variation characteristics that were high in winter and spring and low in summer and autumn. There were obvious differences in PM2.5 concentration between winter and summer， and the convergence of PM2.5 concentration in summer was greater than that in winter. Areas with high PM2.5 concentration also had obvious downward trends， but the downward trends of PM2.5 concentration in the PRD were not obvious compared with those in the YRD and BTH. ③ The PM2.5 concentration time series of the three major urban agglomerations all had significant downward trends： Beijing-Tianjin-Hebei （BTH） > the Yangtze River Delta （YRD） > the Pearl River Delta （PRD）. The PM2.5 concentration had the largest downward trends in winter. The higher the PM2.5 pollution level， the greater the downward trends. ④ The trend component of the PM2.5 concentration time series in the BTH had two change points， and there was one change point in the seasonal component. The trend and seasonal components of the PM2.5 concentration time series in the YRD had no change point. There was no change point in the seasonal component but one change point in the trend component of the PM2.5 concentration time series in the PRD. These results can provide scientific references for regional air pollution control.

[Scale Dependence Between PM2.5 and Meteorological Factors and Its Influencing Factors in "2+26" Cities].

Based on the PM2.5 concentration and meteorological data of "2+26" cities, the variations in PM2.5 time series were analyzed by the continuous wavelet transform(CWT) and discrete wavelet transform(DWT). Wavelet coherence(WTC) and multiple wavelet coherence(MWC) were used to quantify the response relationship between PM2.5 and single/multiple meteorological factors in the time-frequency domain. Partial wavelet coherence(PWC) was used to quantitatively evaluate the influence of atmospheric teleconnection factors on the response relationship. The results showed that:① the concentration of PM2.5 in the "2+26" cities had the spatial distribution characteristics of high in the middle area and low in the peripheral area. The PM2.5 mutation events were mainly concentrated before 2018 and mostly occurred in winter when the meteorological conditions were stable. The annual scale period of 256-512 d was relatively stable, and it was also the dominant period of the PM2.5 time series. ② The coherences between PM2.5 and meteorological factors depended on the time-frequency scale and variable combination. At all time-frequency scales, PM2.5 had strong coherences with relative humidity and temperature. At small and medium time-frequency scales, PM2.5 had strong coherences with wind speed. At large scales, PM2.5 had strong coherences with temperature. The combination of precipitation, temperature, and relative humidity could explain the variation in PM2.5 at all time-frequency scales. ③ At different time-frequency scales, the enhancement/weakening effects of atmospheric teleconnection factors on the response relationship were not the same. At all time-frequency scales, the El Niño-Southern Oscillation(ENSO) had a greater impact on the response relationship between PM2.5 and precipitation/temperature, and the Pacific decadal oscillation(PDO) had a greater impact on the response relationship between PM2.5 and relative humidity/wind speed. These results provide reference for regional air pollution control.

[Spatio-temporal Variations in PM2.5and Its Influencing Factors in the Yangtze River Delta Urban Agglomeration].

To coordinate the contradiction between economic development and environmental pollution and achieve the sustainable development of the economy and society, the spatio-temporal variations in PM2.5 were analyzed based on PM2.5 concentration and meteorological data of the Yangtze River Delta (YRD) urban agglomeration. Wavelet transform coherence (WTC), partial wavelet coherence (PWC), and multiple wavelet coherence (MWC) were used to analyze the multi-scale coupling oscillation between PM2.5 and meteorological factors in the time-frequency domain. The results showed that:① the concentration of PM2.5 in the YRD decreased from northwest to southeast, and the spatial range with high PM2.5 concentration decreased annually. The spatial distribution characteristics of the seasonal average PM2.5 concentration were similar to those of the annual average PM2.5 concentration. PM2.5 concentration exhibited the seasonal variation characteristics of high in winter, low in summer, and transitioning between spring and autumn. ② PM2.5 concentration decreased from 2015 to 2021, and the compliance rate increased. The difference in annual average PM2.5 concentration was decreased with dynamic convergence characteristics. The convergence of PM2.5 concentration in summer was greater than that in winter. During the whole study period, the daily average PM2.5 concentration showed a "U" distribution, and the proportion of days with excellent and good PM2.5 levels were 49.72% and 41.45%, respectively. ③ The wavelet coherence between PM2.5 and meteorological factors was different in different time-frequency domains. The main factors affecting PM2.5 were different in different time-frequency scales. At all time-frequency scales, WTC and PWC showed that wind speed and temperature were the best explanatory variables of PM2.5 variation, respectively. ④ The larger the time-frequency scale, the stronger the interaction of multi-factor combinations to explain PM2.5 variations. The synergistic effect of temperature and wind speed could better explain the variation in PM2.5. These results can provide reference for air pollution control in the YRD.

[MAIAC AOD and PM2.5 Mass Concentrations Characteristics and Correlation Analysis in Beijing-Tianjin-Hebei and Surrounding Areas].

Based on the MAIAC AOD and PM2.5 mass concentration data for the Beijing-Tianjin-Hebei region and surrounding areas from 2014 to 2018, the temporal and spatial differences in Aerosol Optical Depth (AOD) and PM2.5 mass concentrations were explored and their correlation was analyzed by linear regression. The results show that the daily average concentration of PM2.5 exceeds the standard for 33% and 57% of measurements based on the daily average standard values of the World Health Organization IT.1 and IT.2, respectively, indicating serious pollution levels. The annual average concentrations of PM2.5 and Terra and Aqua MAIAC AOD all show downward trends. The PM2.5 concentrations are high in winter and spring and low in summer and autumn; Terra and Aqua AOD values are high in spring and summer and low in autumn and winter. The seasonal and annual average concentrations of PM2.5 and AOD all show the regional pattern of "low in the north and high in the south". High-value areas are mainly located in southern Hebei, southwestern Shanxi, western Shandong, and northern Henan, while low-value areas are mainly located in northwestern Shanxi, northern Hebei, and eastern Shandong. The annual average concentration of PM2.5 is between 27 and 99µg·m-3, and the annual average AOD is between 0.20 and 0.69. The correlation between Aqua AOD and PM2.5 concentration is strong whereas and the correlations between Terra AOD, Aqua AOD, and PM2.5vary significantly in different seasons; overall, correlations are strongest in spring and winter and weakest in summer and autumn. After vertical-humidity correction, the correlation between satellite AOD and PM2.5 data is significantly improved.

[Analysis of Changes and Factors Influencing Air Pollutants in the Beijing-Tianjin-Hebei Region During the COVID-19 Pandemic].

A series of strict control measures were imposed in the Beijing-Tianjin-Hebei region in early 2020 to control the spread of COVID-19. These measures have led to a reduction of anthropogenic air pollutants, providing an opportunity to observe the contribution of human activities to local air pollution. In this study, the control period was divided into four stages:the before, early, middle, and later stages. Based on a variety of data including meteorological, traffic, and industrial manufacturing datasets, statistical methods were combined with spatial analysis to evaluate changes in air pollution and associated human impacts during each stage. In addition, suggestions are made for further regional air pollution control in the Beijing-Tianjin-Hebei area. Key results are as follows:① Overall, the AQI and the concentrations of six air pollutants, especially SO2, PM10, and NO2, were lower during control period than during the equivalent period in 2019 (reductions of 26.5%, 24.3%, and 16.9%, respectively). From the before to later stages, pollutants (except O3) showed a downward trend while O3 increased significantly during the before stage (by 76.2%) and the growth rate slowed during the middle and later stages; ②During the prior stage, Beijing experienced two periods with heavy air pollution days as a result of the local accumulation of pollutants, secondary transformation, and regional transport. The concentration of PM2.5 in February was nearly 60% lower than in February 2014 under similar meteorological conditions in Beijing; ③ Following an increase in traffic volume and industrial activity, changes in air pollutants tended to be stable or slightly increase during the middle and later stages of the control period. The grey relation coefficients between thermal radiation intensity anomalies and the main pollutants in heavy industrial cities were greater than 0.6, which means that the control of industrial emissions remains key to controlling air pollution.

[Pollution Characteristics and Health Risk Assessment of Heavy Metals in PM2.5 Collected in Baoding].

To reveal the pollution characteristics and the health risks of the trace heavy metals in the atmospheric particles in Baoding, Hebei province, PM2.5 samples were collected using a middle volume sampler, and the mass concentrations of V, Cr, Mn, Co, Ni, Cu, Zn, As, Cd, and Pb in the samples were determined by microwave digestion-inductively coupled plasma-mass spectrometry (ICP-MS). The results showed that the PM2.5 concentration in Baoding ranged from 16.84-476.2 µg·m-3. During sampling, 65 samples were above the second-level standard of the Ambient Air Quality Standards (GB 3095-2012) by 54.2%. The most heavy metal elements showed higher levels in nighttime than during the daytime, except for except for Ni, Mn, and Co. Obvious seasonal variation was found with the trend of winter > autumn > spring > summer. The enrichment factors for Cu, Zn, Pb, and Cd were more than 1.5, indicating that those metals mainly came from anthropogenic emissions, such as traffic sources. Health risk assessment results indicated that the non-carcinogenic risk of heavy metals in PM2.5 in Baoding was small, and the carcinogenic risk resulting form As, Cr, Cd, and Co was greater for adults than for children.

A new abietane diterpenoid from Ajuga ovalifolia var. calantha induces human lung epithelial A549 cell apoptosis by inhibiting SHP2.

The Src-homology 2 domain-containing phosphatase 2 (SHP2), encoded by PTPN11, has been reported oncogenic tyrosine phosphatase associated with various tumors and played critical roles in many cell signaling events. Targeting SHP2 by small molecules may be a promising way for cancer therapy. Herein, a new abietane diterpenoid, named 3-acetoxylteuvincenone G (3-AG), was isolated from the whole plants of Ajuga ovalifolia var. calantha. The structure of the new compound was elucidated by means of extensive spectroscopic analyses. Using recombinant enzyme activity assay and cellular thermal shift assay, we found that 3-AG was a selective inhibitor of SHP2. Molecular docking suggested 3-AG displayed an orientation favorable to nucleophilic attack in the catalytic domain of SHP2. 3-AG suppressed A549 cell proliferation (IC50 = 10.79 ± 0.14 µM), invasion and induced cell apoptosis through SHP2/ERK1/2 and SHP2/AKT pathways. In summary, 3-AG, a potent, selective, and efficacious SHP2 inhibitor, may be a promising small molecule to treat human lung epithelial cancer.

[Variation in Pollutant Concentrations and Correlation Analysis with the Vegetation Index in Beijing-Tianjin-Hebei].

Based on 2017 hourly air quality monitoring data, NDVI 16 d synthetic data, and socio-economic data, the air pollution characteristics of Beijing-Tianjin-Hebei were systematically analyzed, and its variation, normalized vegetation index, and the relationship between the index (NDVI) and its impact on socio-economic factors, were analyzed by linear regression analysis and a geographically weighted regression model. The conclusions are as follows:①The overall air pollution in the Beijing-Tianjin-Hebei region is characterized by high-level pollution over the southern plain areas and low-level pollution over the northern mountainous areas. The air pollution increases from north to south, and shows significant spatial heterogeneity. ②From the perspective of seasonal changes, the overall order winter > autumn > spring > summer is observed, and atmospheric pollution in the Beijing-Tianjin-Hebei region shows significant temporal heterogeneity. ③The concentrations of pollutants such as SO2, NO2, CO, PM2.5, and PM10 all have a negative correlation with the NDVI value. Assuming that natural conditions such as climate and topography are relatively consistent, the lower the NDVI value, the more obvious the interference of human activities, the more concentrated the industrial economy layout, and the greater the pollution emissions, the more significant the negative impact on air quality. ④The NDVI reflects the land use, population distribution, and industrial layout to a certain extent, and these factors directly or indirectly determine the level of air pollution emissions and thus indicate the pollution distribution characteristics of the region. ⑤The results of the GWR model calculation show that the higher the level of economic development, the better the correlation between the NDVI and socioeconomic factors, PM2.5, and other pollutant concentrations. The distribution of the NDVI can generally reflect the level of social and economic development. The distribution of the NDVI also correlates to the distribution of PM2.5 to a certain extent.

A new abietane diterpenoid glycoside from ajuga ovalifolia var. calantha.

A new abietane diterpenoid glycoside, ajugaside B (1), along with three known compounds (2-4), were isolated from the whole plants of Ajuga ovalifolia var. calantha. The structure of the new compound (1) was elucidated by means of spectroscopic analyses (HRESIMS, IR, NMR and ECD). All of the isolated compounds were evaluated for their antitumor activities against MGC803, MCF-7, A549, HT29 and HepG2 cell lines. Compounds 3-4 showed moderate cytotoxicity against all tested cell lines with IC50 values of 1.8-7.3 µM.

[Multidimensional poverty measurement of poverty-stricken counties in China's 14 conti-guous destitute areas considering ecological environment]. / 虑及生态环境的十四片区贫困县多维贫困度量.

As an important part of the national poverty alleviation strategy in China, monitoring of poverty-stricken counties is the precondition and guarantee for implementing national precise poverty reduction strategies. Taking 724 poverty-stricken counties in 14 contiguous destitute areas as the study area, we designed a county-level multidimensional poverty measurement index system that reflected the economic state (poverty appearance), social state (living guarantee ability) and ecological environment state (potential capacity of regional development) in fully consideration of the interdependent relationship between ecological vulnerability and economic poverty, and analyzed the poverty degree, poverty type, causes of poverty and the spatial distribution characteristics in multi-scale and multi-angle levels. The results showed that the distribution of poverty level of different counties represented a geometrically olive-shaped pattern that was larger in lower and moderate impoverished counties and smaller in low and high poverty-stricken counties. As far as the distribution of poverty-stricken counties was concerned, the distribution was spatially heterogeneous, presenting a typical stepped structure that was "west-high vs. east-low", where different levels of dotted poverty kernels were scattered. The multidimensional characteristics of poverty-stricken counties represented a wholely strong spatial dependence; however, both High-High areas and Low-Low areas were distributed intensively while both High-Low areas and Low-High areas were distributed discretely. The characteristics of poverty distribution on both sides of the "Hu Line" were obviously different. The number of seven-factor comprehensive poverty-stricken counties was the most, while the location advantages, terrain conditions and poverty alleviation performance were the significant factors affecting the development of poverty reduction. Ecological poverty caused by deterioration of ecological environment and natural endowments is a regional characteristic in most poverty areas of China.

[Enrichment Levels and Comprehensive Pollution Assessment of Dust Heavy Metals in Winter in Beijing].

Dust reflects the natural subsidence of particles and is thus generally accepted as an important environmental indicator. Dust heavy metals find their way into soil or water via atmospheric deposition, potentially damaging plants, aquatic organisms, as well as human beings. In order to study the concentration levels, enrichment degrees, and comprehensive pollution characteristics of the dust heavy metals Cd, Cr, Pb, Cu, Zn, Ni, Co, V, Bi, and Mo in winter in Beijing, 49 groups of dust samples were collected from different locations within the city from November 2013 to March 2014. Heavy metal content (mass percentage) was then measured using Elan DRC Ⅱ type inductively-coupled plasma mass spectrometry (ICP-MS). Results showed that the average content of Cd, Bi, and Mo was less than 10 mg·kg-1, that of Co, Ni, and V was between 10 and 100 mg·kg-1, while that of Pb, Cr, Cu, and Zn was more than 100 mg·kg-1. The amount of Cd, Zn, and Cu in dust samples was generally higher than their secondary standard values in the soil environment. The secondary standard excess rates of Cd, Zn, and Cu were 100%, 97%, and 93.9% in urban environments, and 100%, 100%, and 81.2% in suburban environments, respectively. Results also indicated slight enrichment of Bi, Cu, Ni, and Pb, mainly derived from crustal or soil sources, while Cd, Cr, Mo, and Zn, exhibited mild enrichment, caused by a combination of natural and artificial sources. The paper proposes a "dust heavy metal comprehensive pollution index" model, based on the traditional single pollution assessment method, so as to explore comprehensive pollution characteristics of dust heavy metals in Beijing. Results for the dust heavy metal comprehensive pollution index in Beijing City were in the order of Cd > Zn > Cu > Pb > Cr > Ni > V > Co. Cd, Zn, Cu, and Pb were identified as key pollution factors, with Cd and Zn as primary factors. Results for the dust heavy metal comprehensive pollution index in Beijing suburbs was Cd > Zn > Cu > Pb > Cr > Ni > Co > V. Cd, Zn, Cu, Pb, and Cr were key pollution factors, with Cd and Zn as primary factors.

[Effect of fertilization combinations of nitrogen, phosphorus, and potassium on four phenolic compounds of cultivated Rhodiola crenulata].

This study is aimed to explore the effect of nitrogen, phosphorus and potassium combined application on the active components of Rhodiola crenulata. R. crenulata was used as the research object, "3414" fertilization experiment were conducted with regular fertilization of NPK(N 60 kg·hm⁻², P2O5 100 kg·hm⁻²,KCl 160 kg·hm⁻²) to study the effect of different rates of NPK fertilization on the total amount of 4 phenolic constituents of gallic acid, salidroside, tyrol and ethyl gallate through field test. The results show that the content of salidroside was higher in the treatment of N1P2K1 and N1P2K2, andthe total amount of four phenols was higher in the treatment of N1P2K2 and N2P2K2. The suitable level of nitrogen, phosphorus and potassium promoted the accumulation of the 4 kinds of phenols.The amount of fertilizer recommended by the three factor fertilizer effect equation,(N 0 kg·hm⁻²,P2O5 150 kg·hm⁻²,KCl 31.71 kg·hm⁻²) obtained the highest content of salidroside, and it was 1.54%.（N 35.54 kg·hm⁻²,P2O5 150 kg·hm⁻²,KCl 237.73 kg·hm⁻²ï¼‰obtained the highest content of 4 kinds of phenolic compounds, and it was 1.93%. This study provides a reference for the standardization of artificial planting of endangered Tibetan medicine.

Ajudecumin A from Ajuga ovalifolia var. calantha exhibits anti-inflammatory activity in lipopolysaccharide-activated RAW264.7 murine macrophages and animal models of acute inflammation.

CONTEXT: Ajuga ovalifolia Bur. et Franch. var. calantha (Diels) C. Y. Wu et C. Chen (Labiatae), a traditional Chinese medicine, has been used to treat several inflammatory diseases. OBJECTIVE: To assess the anti-inflammatory activity of ajudecumin A isolated from Ajuga ovalifolia var. calantha, and its possible mechanisms. MATERIALS AND METHODS: Lipopolysaccharide (LPS, 0.5 µg/mL)-stimulated RAW264.7 macrophages were used to assess the anti-inflammatory activity of ajudecumin A (1-40 µM) in vitro. Nitric oxide levels were evaluated by Griess reagent. The mRNA levels of iNOS, COX-2, TNF-α, IL-1ß and IL-6 were determined using qRT-PCR. Phosphorylation of ERK, JNK, p38 MAPK and IκBα were detected by western Blot. To further assess the anti-inflammatory of ajudecumin A in vivo, mice were oral treated with ajudecumin A (10 mg/kg) or dexamethasone (0.25 mg/kg, positive control) for 5 days before administration of carrageenan or xylene. Paw and ear edema were then measured, respectively. RESULTS: Ajudecumin A (10-40 µM) decreased LPS-induced nitric oxide production with an IC50 value of 16.19 µM. Ajudecumin A (20 and 40 µM) also attenuated cell spreading and formation of pseudopodia-like structures, and decreased the mRNA levels of iNOS (55.23-67.04%, p < 0.001), COX-2 (57.58-70.25%, p < 0.001), TNF-α (53.75-58.94%, p < 0.01-0.001), IL-1ß (79.41-87.85%, p < 0.001) and IL-6 (54.26-80.52%, p < 0.01-0.001) in LPS-activated RAW264.7 cells. Furthermore, ajudecumin A suppressed LPS-induced phosphorylation of ERK, p38 MAPK, and IκBα, as well as IκBα degradation (p < 0.05-0.001). Finally, ajudecumin A (10 mg/kg) attenuated carrageenan- and xylene-induced inflammation in mice by about 28 and 24%, respectively. DISCUSSION AND CONCLUSIONS: Ajudecumin A exhibited a potent anti-inflammatory activity in vitro and in vivo through inhibition on NF-κB and ERK/p38 MAPK pathways, suggesting that ajudecumin A may be potentially developed as a lead compound in anti-inflammatory drug discovery.

[Correlation between vertebral bone marrow fat and abdomen fat: a prospective study].

OBJECTIVE: To investigate the correlation between the lumbar bone marrow fat and abdominal fat. METHODS: A total of 68 individuals (32 men and 36 women, aged 21-74 years with a median of 49.5 years) were included in this study. All the subjects underwent spectroscopic examination of the third lumber vertebra with the single voxel method on a 1.5T MR scanner to measure the fat fraction (FF%). Quantitative CT was also performed for measurement of the abdomen subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT). The measurements were compared between subjects aged ≥50 years and those below 50 years, respectively,in male or female subjects. RESULTS: In male subjects, BMI, FF%, VAT or SAT showed no significant differences between the two age groups (P>0.05), and FF% was not correlated with BMI, VAT or SAT (r=0.109, 0.034, 0.066, respectively; P>0.05). In the female subjects, BMI, FF%, VAT and SAT differed significantly between the two age groups (P<0.05), and in ≥50 years group, FF% showed a positive correlation with VAT (r=0.499, P<0.05) but was not correlated with SAT (r=0.221, P>0.05); in<50 years group, FF% was not correlated with VAT or SAT (r=0.076, -0.067, respectively; P>0.05). CONCLUSION: FF% is positively correlated with VAT in female subjects aged beyond 50 years, but is not correlated with VAT or SAT in male subjects or in younger female subjects.

[Retrieving Dustfall Distribution in Beijing City Based on Ground Spectral Data and Remote Sensing].

Dust-fall distribution of vegetation leaves can indicate the degree of air pollution; therefore the analysis of spatial characteristics of urban vegetation dust-fall has important practical significance for making more effective air pollution control policy. Based on the data of weight of dust, spectral reflectance and leaf area of Euonymus japonicus, Sophora japonica, poplar and davidiana collected in the main area of Beijing city, we compared the curve of spectrum of four plants "dust leaves" to "clean leaves"; the correlation analysis between leaf spectral reflectance ratio (Dust/Clean) of narrow band and satellite band was processed with the weight of dust-fall respectively, with application of four plants leaf data. Then, we built the regression model of the satellite band reflectance and NDVI with dustfall weight respectively, and we used the best model to retrieve the dust-fall distribution of vegetation coverage area in Beijing city, furthermore, we obtained the dust distribution of the whole Beijing city through interpolation. Finally, we carried out the rationality verification of the result by the land cover and land use of the high dust region, as well as the average concentration of PM10. The results showed that, dust leaves had an obviously lower reflectance than clean leaves in 780~1 300 nm which belonged to near-infrared bands; therewas a higher correlation between narrow band reflectance and dust-fall weight in 520~620 and 1 390~1 600 nm, up to -0.626; the coefficients of determination (R2) of inversion models were respectively 0.446 and 0.465,which were constructed by green band and NDVI of Landsat8 with dust-fall weight. Using the model established with NDVI to retrieving the dust-fall distribution of Beijing city, the results demonstrate that the distribution of dust-fall is high in north and low in south, high in east and low in west, high in downtown and low in the suburbs. This study offers a low-cost and effective method for investigating dust-fall distribution in urban area, and provides data support to analysis sources of pollution for the environmental protection department.

[Object-oriented aquatic vegetation extracting approach based on visible vegetation indices.] / åŸºäºŽå¯è§å ‰æ¤è¢«æŒ‡æ•°çš„é¢å‘å¯¹è±¡æ¹¿åœ°æ°´ç”Ÿæ¤è¢«æå–æ–¹æ³•.

Using the estimation of scale parameters (ESP) image segmentation tool to determine the ideal image segmentation scale, the optimal segmented image was created by the multi-scale segmentation method. Based on the visible vegetation indices derived from mini-UAV imaging data, we chose a set of optimal vegetation indices from a series of visible vegetation indices, and built up a decision tree rule. A membership function was used to automatically classify the study area and an aquatic vegetation map was generated. The results showed the overall accuracy of image classification using the supervised classification was 53.7%, and the overall accuracy of object-oriented image analysis (OBIA) was 91.7%. Compared with pixel-based supervised classification method, the OBIA method improved significantly the image classification result and further increased the accuracy of extracting the aquatic vegetation. The Kappa value of supervised classification was 0.4, and the Kappa value based OBIA was 0.9. The experimental results demonstrated that using visible vegetation indices derived from the mini-UAV data and OBIA method extracting the aquatic vegetation developed in this study was feasible and could be applied in other physically similar areas.

[Coupling between ecological vulnerability and economic poverty in contiguous destitute areas, China: Empirical analysis of 714 poverty-stricken counties.] / ä¸­å›½è´«å›°åœ°åŒºç”Ÿæ€çŽ¯å¢ƒè„†å¼±æ€§ä¸Žç»æµŽè´«å›°çš„è€¦åˆå ³ç³»­­åŸºäºŽè¿žç‰‡ç‰¹å›°åŒº714个贫困县的实证分析.

Maintaining the coordinated correlation between ecological environment and economic development is one of the important strategies in the new stage of poverty alleviation and development. Taking 714 poverty-stricken counties in contiguous destitute areas as study areas, this paper designed the ecological vulnerability evaluation indicator system based on the ecological sensitivity-resilience-pressure (SRP) conceptual model, as well as the comprehensive poverty evaluation indicators from the perspective of socioeconomic development, so as to build the coupling model to reveal the coupling between ecological vulnerability and economic poverty. The results showed that Hu-Line could act as a feasible partition label to depict the spatial distribution patterns of ecological vulnerability, economic poverty, as well as their coupling degree in contiguous destitute areas, which should be fully taken into consideration the influence of Hu-Line on the east-west pattern classification of national poverty reduction. In addition, there existed a symbiotic positive correlation between ecological vulnerability and economic poverty, therefore, the strategic significance of ecological and environment protection in poverty-stricken areas should be specifically emphasized to reduce economic poverty by synchronously protecting the ecological environment. Approximately half of the counties involved in the study area were in the coordinated type of recession disorders, where the ecological environment quality and the economic development could not be synchronized.

[Distribution Characteristics and Source Analysis of Dustfall Trace Elements During Winter in Beijing].

The dustfall content is one of the evaluation indexes of atmospheric pollution. Trace elements especially heavy metals in dustfall can lead to risks to ecological environment and human health. In order to study the distribution characteristics of trace elements, heavy metals pollution and their sources in winter atmospheric dust, 49 dustfall samples were collected in Beijing City and nearby during November 2013 to March 2014. Then the contents (mass percentages) of 40 trace elements were measured by Elan DRC It type inductively coupled plasma mass (ICP-MS). Test results showed that more than half of the trace elements in the dust were less than 10 mg x kg(-1); about a quarter were between 10-100 mg x kg-1); while 7 elements (Pb, Zr, Cr, Cu, Zn, Sr and Ba) were more than 100 mg x kg(-1). The contents of Pb, Cu, Zn, Bi, Cd and Mo of winter dustfall in Beijing city.were respectively 4.18, 4.66, 5.35, 6.31, 6.62, and 8.62 times as high as those of corresponding elements in the surface soil in the same period, which went beyond the soil background values by more than 300% . The contribution of human activities to dustfall trace heavy metals content in Beijing city was larger than that in the surrounding region. Then sources analysis of dustfall and its 20 main trace elements (Cd, Mo, Nb, Ga, Co, Y, Nd, Li, La, Ni, Rb, V, Ce, Pb, Zr, Cr, Cu, Zn, Sr, Ba) was conducted through a multi-method analysis, including Pearson correlation analysis, Kendall correlation coefficient analysis and principal component analysis. Research results indicated that sources of winter dustfall in Beijing city were mainly composed of the earth's crust sources (including road dust, construction dust and remote transmission of dust) and the burning of fossil fuels (vehicle emissions, coal combustion, biomass combustion and industrial processes).

Dustfall Heavy Metal Pollution During Winter in North China.

In order to study heavy metal pollution in dustfall during Winter in North China, forty-four dustfall samples were collected in North China Region from November 2013 to March 2014. Then forty trace elements content were measured for each sample by inductively coupled plasma-mass spectrometry. Finally, the contamination characteristics of the main heavy metals were studied through a multi-method analysis, including variability analysis, Pearson correlation analysis and principal component analysis. Results showed that the relative contents of cadmium (Cd), zinc (Zn), copper (Cu), bismuth (Bi), lead (Pb) exceeded the standards stipulated in Chinese soil elements background values by amazing 4.9 times. In this study, conclusions were drawn that dustfall heavy metal pollution in the region was mainly caused by transport pollution, metallurgy industrial pollution, coal pollution and steel industrial pollution.

Bergapten promotes bone marrow stromal cell differentiation into osteoblasts in vitro and in vivo.

Many recent studies have suggested that bergapten (BP), a class of native compound with numerous biological activities such as anti-resorptive properties, may exert protective effects against postmenopausal bone loss. However, it remains unknown whether BP regulates or improves the osteogenic function of bone marrow stromal cells (BMSCs) in the treatment and prevention of osteoporosis. In our study, BMSCs were cultured in osteogenic induction medium with the addition of BP for 2 weeks and an ovariectomized mouse model of osteoporosis was used to investigate the anti-resorptive effect of BP by gavage administration for 3 months. The concentrations of BP used were 0.1, 1, and 10 µmol/L in vitro and the gavage dose was 20 mg/kg/d. The result of our study indicated that BP promotes the expression of alkaline phosphatase (ALP) by BMSCs in vitro in a dose-dependent manner, as revealed by ALP staining. Runt-related transcription factor 2 and osteocalcin were up-regulated both in vitro and vivo, while osterix and collagen Iα1, assessed by immunofluorescence and immunohistochemistry, were correspondingly raised in the presence of BP in BMSCs in vitro. In addition, a protective effect of BP against ovariectomy-induced bone loss was found by distal femur micro-CT scanning, with improvements of bone metabolism parameters such as bone mineral density, trabecular number, and trabecular separation. Furthermore, WNT/ß-catenin signaling was activated in the presence of BP in BMSCs in osteogenic culture. Finally, BP promoted differentiation of BMSCs into osteoblasts by up-regulation of the WNT/ß-catenin pathway.