ITA and Beast methods were used to quantitatively analyze the nonlinear process of a PM concentration time series based on the PM concentration data of the three major urban agglomerations in China. The results showed that: ① the degree of the PM pollution in the three major urban agglomerations had decreased, and the high-concentration areas had noticeably shrunk. The degree of spatial polarization of PM concentration was reduced, and the spatial difference was narrowed.
View Article and Find Full Text PDFBased on the PM concentration and meteorological data of "2+26" cities, the variations in PM 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 PM 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.
View Article and Find Full Text PDFTo coordinate the contradiction between economic development and environmental pollution and achieve the sustainable development of the economy and society, the spatio-temporal variations in PM were analyzed based on PM 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 PM and meteorological factors in the time-frequency domain. The results showed that:① the concentration of PM in the YRD decreased from northwest to southeast, and the spatial range with high PM concentration decreased annually.
View Article and Find Full Text PDFBackground: Cerebral spinal fluid (CSF) leak remains an important issue in endoscopic endonasal surgery (EES). A standard protocol for skull base closure has not yet been established, and the application of rigid buttress has not been given sufficient attention. To emphasize the functions of support and fixation from rigid buttress in reconstruction, we introduced the cruciate embedding fascia-bone flap (CEFB) technique using autologous bone graft to buttress the fascia lata attachment to the partially sutured skull base dural defect and evaluated its efficacy in a consecutive case series of grade II-III CSF leaks in EES.
View Article and Find Full Text PDFBased on the MAIAC AOD and PM 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 PM mass concentrations were explored and their correlation was analyzed by linear regression. The results show that the daily average concentration of PM 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.
View Article and Find Full Text PDFA 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.
View Article and Find Full Text PDFTo 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 PM concentration in Baoding ranged from 16.
View Article and Find Full Text PDFThe 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.
View Article and Find Full Text PDFBased 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.
View Article and Find Full Text PDFAs 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.
View Article and Find Full Text PDFA new abietane diterpenoid glycoside, ajugaside B (), along with three known compounds (), were isolated from the whole plants of var. . The structure of the new compound () was elucidated by means of spectroscopic analyses (HRESIMS, IR, NMR and ECD).
View Article and Find Full Text PDFDust 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.
View Article and Find Full Text PDFThis 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.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
September 2016
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.
View Article and Find Full Text PDFMaintaining 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.
View Article and Find Full Text PDFYing Yong Sheng Tai Xue Bao
May 2016
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.
View Article and Find Full Text PDFNan Fang Yi Ke Da Xue Xue Bao
February 2016
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.
Guang Pu Xue Yu Guang Pu Fen Xi
October 2015
Vegetation indices are the simplest and most effective metric parameters representing the features of vegetation cover and growth condition. This paper used Euonymus japonicas Thunb as a study case and collected 200 leaf samples in 20 locations. Using electronic analytical balance and ASD hyperspectral radiometer with Win FOLIA leaf area meter obtained the data of the amount of dust, spectral information and leaf area.
View Article and Find Full Text PDFThe 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.
View Article and Find Full Text PDFBull Environ Contam Toxicol
October 2015
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.
View Article and Find Full Text PDFMany 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.
View Article and Find Full Text PDFHyperspectral reflectance information is a crucial method to detect total nitrogen content in plant leaves, meanwhile, vegetation nitrogen content has a strong relationship with nitrogen in water. Taking Mencheng Lake Wetland Park supplied with reclaimed water as study area, the vegetation hyperspectral data (Phragmites australis and Typha angustifolia), and the content of total nitrogen in water were detected to investigate the feasibility of estimating total nitrogen content in reclaimed water based on hyperspectral reflectance information from emergent plants. We established simple linear regression model, stepwise multiple linear regression model and partial least square regression model based on four hyperspectral indices (spectral indices, normalized difference indices, trilateral parameters, absorption feature parameters), respectively.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
October 2013
In order to build inversion model of dust-fall weight by hyperspectral data, 30 samples were collected in Beijing. Through electronic balance and Analytical Spectral Devices FieldSpec Pro (ASD) analysis, the "dust leaves" and the "clean leaves" weight and spectral reflectance were determined respectively, which also obtained information of dust weight and spectral features. Then, based on tradition and partial least squares (PLS) model's analysis, the relationship between dust weight and spectral reflectance was explored.
View Article and Find Full Text PDFTo study the effects of meteorological and traffic factors on the PM2.5 and PM10 concentrations, 28 samples were taken in the Third Ring Road of Beijing, and dust fall weight, velocity of vehicle, traffic volume, temperature, humidity, wind speed, PM2.5 and PM10 concentration data were collected for these samples.
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