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1.
Huan Jing Ke Xue ; 42(7): 3107-3117, 2021 Jul 08.
Article in Chinese | MEDLINE | ID: mdl-34212636

ABSTRACT

Spatial features of PM2.5 concentration in the Yangtze River Delta in 2016 were analyzed using remote sensing data. Selecting factors among meteorology, topography, vegetation, and emission list of air pollutants, factors and their interaction effects on the spatial distribution of PM2.5 concentration were studied based on GAM, with an evaluation unit of 0.25°×0.25° for the grid. It showed that:① With a more significant difference between the north and south, PM2.5 concentration was generally higher in the north and west but lower in the south and east. In the southern part of the delta, the concentration was mostly lower than 35 µg·m-3, with noncompliance of the PM2.5 concentration scattered in urban areas like islands. Meanwhile, PM2.5 concentration is generally over 35 µg·m-3, and the pollution appeared like sheets. ② Besides, PM2.5 concentration showed an apparent positive spatial autocorrelation with "High-High" PM2.5 agglomeration areas in the north of the delta and "Low-Low" PM2.5 agglomeration areas in the south. ③ Based on GAM, hypsography, temperature, and precipitation negatively affected PM2.5 concentration, whereas pollutant emissions positively affected it. The effect of wind was minor when its speed <2.5 m·s-1, and more negatively significant when its speed ≥ 2.5 m·s-1. Hypsography, temperature, and precipitation were higher in the southern part of the delta, but they were lower in the northern part, leading to a higher PM2.5 concentration in the northern parts and lower in the southern parts. A higher wind speed in the east and lower in the west also led to a concentration difference between them. ④ All factors had passed a significant pair interaction test, except for hypsography and PM2.5 emission, and they all showed a significant interaction effect on the distribution of PM2.5 in the Yangtze River Delta.


Subject(s)
Air Pollutants , Air Pollution , Air Pollutants/analysis , Air Pollution/analysis , China , Environmental Monitoring , Particulate Matter/analysis , Rivers
2.
Huan Jing Ke Xue ; 41(3): 1013-1024, 2020 Mar 08.
Article in Chinese | MEDLINE | ID: mdl-32608601

ABSTRACT

Intensive social and economic activity has led to serious pollution in the Yangtze River economic belt since 2000. It is urgent to study the evolution of the distribution of PM2.5 concentration and its influencing factors in this area, to adopt new ways of development into practice and promote comprehensive regional air pollution prevention and control. Based on PM2.5 concentration estimated by remote sensing retrieval, this paper studied the evolution of the distribution of PM2.5 concentration in the Yangtze River economic belt from 2000 to 2016, and analyzed spatial non-stationarity of the influence of natural and socio-economic factors on this evolution via a geographically weighted regression model. The results showed that:①The general law of PM2.5 concentration presented as higher in the east and lower in the west, with a significant trait of the pollution agglomerations corresponding to urban agglomerations. ②Taking the year 2007 as a divide, annual concentration of PM2.5 went through a pattern of annually increasing from 2000 to 2007. and then wavelike decreasing from 2007 to 2016. The annual average concentration increased to 44.1 µg·m-3 in 2007 from the record of 27.2 µg·m-3 in 2000, and then decreased to 33.6 µg·m-3 in 2016. In terms of regions polluted, before 2007, it covered areas including the Yangtze River Delta urban agglomerations, the Yangtze River Middle Reaches urban agglomerations, and the Chengdu-Chongqing urban agglomerations, before quickly stretching to their neighboring areas; after 2007, the extent of areas covered shrank. ③Based on spatial auto-correlation analysis, PM2.5 concentration had a significant spatial auto-correlation with hot spots spread over Shanghai, Jiangsu, north-central Anhui, northern Zhejiang, and the central part of Hubei, while cool spots were located in Yunnan, the western and southern parts of Sichuan, and the western part of Guizhou. ④There is a space-time discrepancy by socio-economic and natural factors in the distribution of PM2.5 concentration. The socio-economic factors mainly have a positive influence on the concentration, whereas precipitation, one of the natural factors, has a negative influence. The remaining natural factors not only varied in their degree of influence, but also triggered the influence either in a positive or negative manner from time to time and space to space.

3.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-344324

ABSTRACT

<p><b>OBJECTIVE</b>To determine the inhibitory effects of BIO-1211, a very late antigen-4 (vla-4) antagonist, on bronchoconstriction and neutrophil adhesion in rats.</p><p><b>METHODS</b>For evaluating ovalbumin-induced bronchoconstriction in the sensitized rats, the changes in lung resistance (RL) and lung dynamic compliance (C(dyn)) were determined after antigen challenge. Neutrophils from the rats were used to determine fibronectin and serum-induced cell adhesion. The effect of BIO-1211 on wheezing was determined after inhalation of histamine and acetylcholine in guinea pigs.</p><p><b>RESULT</b>BIO-1211 aerosol at 1, 3 and 10 mg/ml significantly inhibited the changes in lung resistance and lung dynamic compliance after antigen challenge in the sensitized rats in a dose-dependent manner. BIO-1211 at 25, 50, 100 and 200 microgram/ml inhibited the fibronectin-induced neutrophil adhesion by 23.5%, 24.6%, 61.4% and 58.1%, respectively, and serum-induced adhesion by 29.9%, 35.9%, 35.3% and 15.4%, respectively. Inhalation of 10 mg/ml BIO-1211 did not show any protection against histamine and acetylcholine-induced bronchoconstriction.</p><p><b>CONCLUSION</b>BIO-1211 inhibits bronchoconstriction and neutrophil adhesion, which may be associated with its effect against bronchoconstriction in rats.</p>


Subject(s)
Animals , Female , Male , Rats , Administration, Inhalation , Asthma , Drug Therapy , Bronchoconstriction , Physiology , Bronchodilator Agents , Pharmacology , Cell Adhesion , Guinea Pigs , Neutrophils , Cell Biology , Oligopeptides , Pharmacology
4.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-344322

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the immunoregulatory effects of pertussis protein on airway inflammatory, IFN-gamma/IL-4 ratio in bronchoalveolar lavage fluids(BALF) and airway hyperresponsiveness (AHR) in the sensitized mice.</p><p><b>METHODS</b>The sensitized mice were reexposed to ovalbumin and the airway response to methacholine injection was monitored. Inflammatory cells and cytokines IFN-gamma/IL-4 ratio in BALF were measured. Lung tissue specimens were collected for histological examination.</p><p><b>RESULT</b>Intramuscular injection or intranasal instillation of pertussis protein inhibited changes in lung resistance and lung dynamic compliance, upregulated IFN-gamma/IL-4 ratio and decreased eosinophil accumulation in a dose-dependent manner. Pathological examination showed that goblet cell hyperplasia and inflammatory cells infiltration in lung tissue were suppressed by pertussis protein.</p><p><b>CONCLUSION</b>Pertussis protein inhibits the inflammation and regulates the function of lungs in asthma mice, suggesting its potential application in treatment of asthma.</p>


Subject(s)
Animals , Male , Mice , Albumins , Asthma , Allergy and Immunology , Therapeutics , Bacterial Proteins , Allergy and Immunology , Pharmacology , Bacterial Toxins , Allergy and Immunology , Pharmacology , Bronchoalveolar Lavage Fluid , Chemistry , Interferon-gamma , Interleukin-4 , Methacholine Chloride , Mice, Inbred ICR
5.
Ying Yong Sheng Tai Xue Bao ; 18(4): 756-60, 2007 Apr.
Article in Chinese | MEDLINE | ID: mdl-17615867

ABSTRACT

In this paper, the calorific values of Pinus koraiensis-broadleaved mixed forest litters and soil microfauna in China temperate zone were determined, with their seasonal variation patterns studied. The results showed that both the calorific values and their seasonal variation patterns were differed with the kinds of tree species litters and soil macrofauna in the mixed forest. The mean gross calorific value (GCV) of P. koraiensis litter was the highest (19.71 kJ x g(-1)), followed by Betula costata (18.22 kJ x g(-1)), Tilia amurensis (18.13 kJ x g(-1)), mixed litter (17.91 kJ x g(-1)), Fraxinus mandshurica (16.94 kJ x g(-1)), and Acer mono (16.25 kJ x g(-1)). With the decomposition of litter, the GCV of P. koraiensis and A. mono litters decreased, while that of F. mandshurica litter had little change. The GCV of T. amurensis and B. costata litters presented an increasing trend in the next year of decomposition. Among the marofauna, scolopendra had the highest GCV (22.07 kJ x g(-1)), followed by earthworm (16.72 kJ x g(-1)) and diplopod (13.28 kJ x g(-1)). Earthworm and diplopod had the identical seasonal variation pattern of GCV, while scolopendra was different from them. There was no significant relationship between the seasonal variation of GCV in litters and soil macrofauna.


Subject(s)
Coleoptera/metabolism , Energy Metabolism , Pinus/metabolism , Soil/analysis , Trees/metabolism , Animals , Coleoptera/physiology , Ecosystem , Environment , Organic Chemicals/analysis , Pinus/physiology , Seasons , Trees/physiology
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