Changes in source composition of wet nitrate deposition after air pollution control in a typical area of Southeast China.

In recent years, China has adopted numerous policies and regulations to control NOx emissions to further alleviate the adverse impacts of NO3--N deposition. However, the variation in wet NO3--N deposition under such policies is not clear. In this study, the southeastern area, with highly developed industries and traditional agriculture, was selected to explore the variation in NO3--N deposition and its sources changes after such air pollution control through field observation and isotope tracing. Results showed that the annual mean concentrations of NO3--N in precipitation were 0.67 mg L-1 and 0.54 mg L-1 in 2014-2015 and 2021-2022, respectively. The average wet NO3--N depositions in 2014-2015 and 2021-2022 was 7.76 kg N ha-1 yr-1 and 5.03 kg N ha-1 yr-1, respectively, indicating a 35% decrease. The δ15N-NO3- and δ18O-NO3- values were lower in warm seasons and higher in cold seasons, and both showed a lower trend in 2021-2022 compared with 2014-2015. The Bayesian model results showed that the NOx emitted from coal-powered plants contributed 53.6% to wet NO3--N deposition, followed by vehicle exhaust (22.9%), other sources (17.1%), and soil emissions (6.4%) during 2014-2015. However, the contribution of vehicle exhaust (33.3%) overpassed the coal combustion (32.3%) and followed by other sources (25.4%) and soil emissions (9.0%) in 2021-2022. Apart from the control of air pollution, meteorological factors such as temperature, precipitation, and solar radiation are closely related to the changes in atmospheric N transformation and deposition. The results suggest phased achievements in air pollution control and that more attention should be paid to the control of motor vehicle exhaust pollution in the future, at the same time maintaining current actions and supervision of coal-powered plants.

Prevention of Venous Thrombosis of Lower Limbs after Cesarean Section Based on Smart Medical Air Pressure Therapy Instrument.

Affected by the environment, the incidence of lower extremity venous thrombosis after cesarean section is gradually increasing, and postoperative nursing is becoming more and more important. The intelligent medical air pressure therapy instrument is a common and effective postpartum nursing method. This paper studies the role of pneumatic therapeutic apparatus in the prevention of lower extremity venous thrombosis after cesarean section in smart medicine, describes its importance in nursing, and analyzes the role of pneumatic therapeutic apparatus and smart medicine combined with the postoperative nursing situation of patients with cesarean section in our hospital. In this paper, we aggregate the description text of six levels of hospital intelligent service grading evaluation. In order to show the characteristics of each level and the requirements of each level of hospital intelligent service, we can roughly see the differences between different levels. Research shows that with the construction of medical information platform, more and more medical processes rely on hospital information system, which promotes the integration of medical platform and the interconnection of medical equipment, provides convenient services for patients, and provides patients with easier access to services. At the same time, the massive data generated by appointment, nursing, treatment, and other activities will be recorded, and the pneumatic therapeutic instrument can avoid the occurrence of 60% lower extremity venous thrombosis. The data of air pressure therapeutic instrument is dynamic, and its performance is mainly reflected in the recording of dynamic index data.

Pterostilbene pre-treatment reduces LPS-induced acute lung injury through activating NR4A1.

CONTEXT: Pterostilbene (PTE), a common polyphenol compound, exerts an anti-inflammatory effect in many diseases, including acute lung injury (ALI). OBJECTIVE: This study explores the potential mechanism of PTE pre-treatment against lipopolysaccharide (LPS)-induced ALI. MATERIALS AND METHODS: Sixty Sprague-Dawley rats were divided into control, ALI, 10 mg/kg PTE + LPS, 20 mg/kg PTE + LPS, and 40 mg/kg PTE + LPS groups. At 24 h before LPS instillation, PTE was administered orally. At 2 h before LPS instillation, PTE was again administered orally. After 24 h of LPS treatment, the rats were euthanized. The levels of inflammatory cells and inflammatory factors in the bronchoalveolar lavage fluid (BALF), the expression of nuclear receptor subfamily 4 group A member 1 (NR4A1), and the nuclear factor (NF)-κB pathway-related protein levels were detected. NR4A1 agonist was used to further investigate the mechanism of PTE pre-treatment. RESULTS: After PTE pre-treatment, the LPS induced inflammation was controlled and the survival rate was increased to 100% from 70% after LPS treatment 24 h. For lung injury score, it decreased to 1.5 from 3.5 after treating 40 mg/kg PTE. Compared with the control group, the expression of NR4A1 in the ALI group was decreased by 20-40%. However, the 40 mg/kg PTE pre-treatment increased the NR4A1 expression by 20-40% in the lung tissue. The results obtained with pre-treatment NR4A1 agonist were similar to those obtained by pre-treatment 40 mg/kg PTE. CONCLUSIONS: PTE pre-treatment might represent an appropriate therapeutic target and strategy for preventing ALI induced by LPS.

Changes of δ15N values during the volatilization process after applying urea on soil.

Ammonia (NH3) volatilized from soils plays an important role in N cycle and air pollution, thus it is important to trace the emission source and predict source contributions to development strategies mitigating the environmental harmful of soil NH3 volatilization. The measurements of 15N natural abundance (δ15N) could be used as a complementary tool for apportioning emissions sources to resolve the contribution of multiple NH3 emission sources to air NH3 pollution. However, information of the changes of δ15N-NH3 values during the whole volatilization process under different N application rates are currently lacking. Hence, to fill this gap, we conducted a 15-day incubation experiment included different urea-N application rates to determine δ15N values of NH3 during volatilization process. Results showed that volatilization process depleted 15N in NH3. The average δ15N value of NH3 volatilized from the 0, 20, 180, and 360 kg N ha-1 treatment was -16.2 ± 7.3‰, -26.0 ± 5.4‰, -34.8 ± 4.8‰, and -40.6 ± 5.7‰. Overall, δ15N-NH3 values ranged from -46.0‰ to -4.7‰ during the whole volatilization process, with lower in higher urea-N application treatments than those in control. δ15N-NH3 values during the NH3 volatilization process were much lower than those of the primary sources, soil (-3.4 ± 0.1‰) and urea (-3.6 ± 0.1‰). Therefore, large isotopic fractionation may occur during soil volatilization process. Moreover, negative relationships between soil NH4+-N and NH3 volatilization rate and δ15N-NH3 values were observed in this study. Our results could be used as evidences of NH3 source apportionments and N cycle.

The Influence of Different Forest Characteristics on Non-point Source Pollution: A Case Study at Chaohu Basin, China.

Forestland is a key land use/land cover (LULC) type that affects nonpoint source (NPS) pollution, and has great impacts on the spatiotemporal features of watershed NPS pollution. In this study, the forestland characteristics of the Chaohu Basin, China, were quantitatively represented using forestland types (FLTs), watershed forest coverage (WFC) and forest distance from the river (DFR). To clarify the impact of forests on NPS pollution, the relationship between forestland characteristics and watershed nutrient outputs (TN and TP) was explored on a monthly scale using SWAT (Soil and Water Assessment Tool) and the period simulation was 2008-2016. The results showed that: (1) the TN and TP showed similar output characteristics and the rainy season was the peak period of nitrogen and phosphorus output. (2) Among the forestland characteristics of forestland types, watershed forest coverage and forest distance from the river, watershed forest coverage and forest distance from the river had greater effects than forestland types on the control of watershed nutrient outputs (TN and TP). (3) In different forestland types, the watershed nutrient outputs intensity remained at the lowest level when the FLTs was mixed forest, with a TN output of 1244.73kg/km2 and TP output of 341.39 kg/km2. (4) The watershed nutrient outputs and watershed forest coverage were negatively correlated, with the highest watershed forest coverage (over 75%) reducing the TN outputs by 56.69% and the TP outputs by 53.46% compared to the lowest watershed forest coverage (below 25%), it showed that in areas with high forest land coverage, the non-point source pollution load in the watershed is smaller than in other areas. (5) forest distance from the river had an uncertain effect on the TN and TP output of the basin, the forestland itself is a source of pollution, but it also has the function of intercepting pollution movement; the forest distance from the river in the range of 500-1000 m had the lowest NPS pollution. Considering the different forest characteristics and topographical factors, an optimal allocation mode of differentiated forest land was proposed, these suggestions will provide a scheme for surface source pollution prevention and control in the basin. This research gap is the basis of real forestland optimization. We may optimize the forestland layout for NPS pollution prevention and control by clarifying the internal mechanism.

[Spatiotemporal variability of soil fertility parameters in Xinhui District of Guangdong Province].

By the methods of geostatistics and GIS, this paper studied the spatial distribution patterns of pH, organic matter, total nitrogen (N) and total phosphorus (P) in cultivated soils of Xinhui District, Guangdong Province from 1982 to 2003. The paired samples t test and Kriging results showed that soil pH and organic matter content were significantly lower in 2003 than in 1982, while the contents of soil total N and total P were in adverse. The spatial distribution of test parameters changed to different degrees over the past 20 years. Soil pH tended to decrease in most areas of the study district, soil organic matter decreased except at the banks of Yinzhou Lake and parts of south and northwest, soil total N increased in most areas except the parts of east and northwest, and soil total P increased in most areas.

[Spatial variability of nutrients in cultivated soils of Xinhui District, Jiangmen City].

Employing geostatistical methods and GIS technology, this paper studied the spatial distribution characteristics of pH, organic matter, CEC, total nitrogen, available phosphorus and slowly available potassium in cultivated soils of Xinhui District, Jiangmen City. All the test variables were normally or log normally distributed. Semivariogram analysis showed that soil nutrients were moderately spatially-dependent in a given spatial range, except that soil total nitrogen was strongly spatially-dependent. It was shown from Kriging analysis that soil pH and CEC was the highest in the northeast, and soil organic matter content was higher in the middle and northeast investigation region. The area with 1.5-2.0 g x kg(-1) soil total nitrogen content accounted for 75.7% of the investigated region, mainly distributed in the west and east, that with > 40 mg x kg(-1) soil available phosphorus content was accounted for 48.7%, mainly distributed in the west and northeast, and the area that slowly available potassium content was 160-350 mg x kg(-1) accounted for 48.1%, mainly distributed in the east, northeast and the middle.