Role of post-hemorrhagic shock mesenteric lymph drainage in restoring balance of ACE/ACE2 in kidney of mice     

LIU Jun-fen  JIANG Li-na  ZHANG Li-min  LIU Gui-qing  ZHAO Zi-gang  LIU Sheng-jun  NIU Chun-yu 《园艺学报》2015,31(11):2096-2100

AIM: To study the role of post-hemorrhagic shock mesenteric lymph (PHSML) drainage on the balance of angiotensin-converting enzyme (ACE) and ACE2 in the kidney. METHODS: A hemorrhagic shock model was established and then fluid resuscitation was performed to the animals in shock and shock+drainage groups, and the PHMSL was drained in shock+drainage group after fluid resuscitation. After 6 h of resuscitation, the mRNA expression of ACE, ACE2, angiotensin Ⅱ (Ang Ⅱ) type 1 receptor (AT1R) and Mas-related G-protein-coupled receptor (MasR), and the levels of Ang Ⅱ and Ang (1-7) in the renal tissues were observed. RESULTS: Hemorrhagic shock increased the levels of ACE mRNA, AT1R mRNA and Ang Ⅱ, and decreased the levels of ACE2 mRNA, MasR mRNA and Ang(1-7) in the kidney. PHSML drainage abolished the effect of hemorrhagic shock on ACE2 and AT1R mRNA expression. Meanwhile, PHSML drainage reduced the hemorrhagic shock-induced increases in the ratios of ACE/ACE2, Ang Ⅱ/Ang(1-7) and AT1R/MasR. CONCLUSION: The PHSML drainage restores the balance of ACE/ACE2, which is beneficial to alleviate acute kidney injury following hemorrhagic shock in the mice.  相似文献   

Re-think urban drainage following a SuDS retrofitting approach against urban flooding: A modelling investigation for an Italian case study     

《Urban Forestry & Urban Greening》2022

In the last decades, urban sprawl and soil sealing led to an increase of urban flooding phenomena. Sustainable Drainage Systems (SuDS) seem able to weaken stormwater-related criticalities, enhancing sustainability and city resilience.Relying on a detailed and feasible preparatory study of SuDS feasible retrofit design, based on a punctual identification of the areas suitable for retrofitting and the most appropriate combination of SuDS technologies, the reported research aimed to assess the effectiveness of a sustainable drainage approach in Sesto Ulteriano (Italy), an urban catchment suffering from stormwater management concerns. In particular, using the approach of a typical scenario analysis, this comparative modeling analysis involved SWMM5 for the assessment of the differences in the catchment hydrological behaviour between the mentioned specific and feasible SuDS retrofitting scenarios and a potential one, where non-specificity is considered for SuDS retrofitting location. Besides, the analyses focused on investigating how rainfall severity, areal extension and land use typical feature could influence the effectiveness of the sustainable redevelopment of the urban area.Results indicate that SuDS projects based on potential designs, which does not account for the feasible suds location, might result in a significant overestimation of the hydrological benefit. They showed, indeed, an improved hydrological performance, with average total volume reductions of the Combined Sewer Overflows up to over 70 % (retrofitting the 8.3 % of the catchment area), that is about 40 % higher than those obtained under the same areal extension by the feasible scenarios. Moreover, it was found that there could be an optimal SuDS retrofitting percentage above which additional hydrological benefits are undetectable. Land use, resulting in the variability in the degree of imperviousness necessarily associated to a variability in the retrofitting potential, also seemed to affect SuDS hydrological performance and for this reason should be included in an overall assessment. SuDS also proved to act successfully on the actual maximum percentage of nodes of the drainage network above a 0.7 filling degree threshold (about 52 % under 10-year return period rainfall) reducing it to 24 % with a feasible retrofitting involving the 8.3 % of the study area.  相似文献   

Dynamic Monitoring of the Mud   总被引：2，自引：0，他引：2  

ZHANG Shen-qiang  ZHU Shou-jun  LIU Yu-lan  ZHANG Zhi-hao .College of Resources & Environment  Northwest A & F University  Yangling   《（《农业科学与技术》）编辑部》2008,(4)

[Objective] The research aimed to provide basic files and theoretical guidance for constructing sluicing-siltation dam using soil with high clay content soil.[Method] The soils of Dagou basin near Xiwu Village of Baishui County,Shaanxi Province were taken as experimental materials.pvc pipes with same height and diameter were used to construct testing model for dynamically determining settlement,shear strength,wet density of grouting bulk under 2 different grouting speeds(15 cm/d and 25 cm/d).[Result] Under different grouting speeds,general change trend was similar during grouting course.The subsidence,deformation,shear strength and wet density increased with the increase of grouting speed.Five or six days after grouting,daily displacement under 25 cm/d grouting speed was fewer than that under 15 cm/d grouting speed.[Conclusion] The increase of grouting speed could shorten the time for reaching the same subsidence,deformation,shear strength and wet density and increased displacement at the initial stage of grouting,however,with the increase of grouting time,lower grouting bulk was bad for displacement at later grouting period because it was near impermeable layer.  相似文献   

A preliminary study of an alternative controlled drainage strategy in surface drainage ditches: Low-grade weirs   总被引：3，自引：0，他引：3  

R. Krger  C.M. Cooper  M.T. Moore 《Agricultural Water Management》2008,95(6):678-684

This study examined hydrological characteristics of low-grade weirs, an alternative controlled drainage strategy in surface drainage ditches. Chemographs of vegetated and clear scraped (control) replicates of weir vs. non-weir treatments were compared to determine differences in time to peak (T_p) and time to base (T_b). Drainage ditches T_p and T_b were affected by both vegetation and weir presence. The order of treatment efficiency for T_p was observed to be: non-vegetated non-weir < vegetated non-weir < non-vegetated weir < vegetated weir. Furthermore, T_b for each ditch was the reverse relationship from T_p where vegetated weir > non-vegetated weir > vegetated non-weir > non-vegetated non-weir. Low-grade weirs increase chemical retention time (vegetated and clear scraped), the average time a molecule of contaminant remains in the system. Future research in water quality improvement and weir management will yield useful information for non-point source pollutant reduction.  相似文献   

杭埠河流域土地利用数据库系统研究与开发     

雷能忠  马众模  蒋旭东 《中国农学通报》2005,21(5):411-411

土地利用数据是进行流域农业面源污染治理的重要基础资料。以国产地理信息系统软件SupMap作为开发平台建立的杭埠河流域1: 5万土地利用数据库系统具有批量数据采集、管理、更新功能,以及运行稳定、安全可靠和很好的可扩展性特点。文章详细介绍了系统数据采集方法、数据组织方式、数据更新和数据库应用系统功能实现。  相似文献   

不同排水体制对内秦淮河污染负荷的比较分析     

钱钧  刘祥  秦文浩  朱亮 《安徽农业科学》2014,(14):4367-4370

排水体制和管网系统是城市基础设施建设的重要组成部分,不同排水体制对流域水环境污染存在明显差异.理论计算结果表明,在秦淮河流域分流制条件下,全年COD、NH3-N平均入河总量分别为1 057.2 t、15.9 t,其中51.0％、48.4％来源于中雨径流雨水;合流制条件下,全年COD、NH3-N平均入河总量分别为1 517.6 t、29.9t,其中82.2％、74.9％来源于大雨污水溢流.负荷比较分析结果表明,不同排水体制在3种雨型条件下,各河段NH3-N负荷无明显差异,主要表现在中雨COD负荷不同.中雨时,分流制雨水中COD负荷约是合流制溢流污水的2～3倍;而大雨时,合流制溢流污水与分流制径流雨水负荷相近.总之,分流制雨水径流污染不容忽视,合流制溢流污水污染应结合降雨强度及其他因素综合考虑.  相似文献   

Evaluation of the water use efficiency of alternative farm practices at a range of spatial and temporal scales: A conceptual framework and a modelling approach     

A.D. Moore  M.J. RobertsonR. Routley 《Agricultural Systems》2011,104(2):162-174

Water is the principal limiting resource in Australian broadacre farming, and the efficiency with which farmers use water to produce various products is a major determinant both of farm profit and of a range of natural resource management (NRM) outcomes. We propose a conceptual framework based on multiple water use efficiencies (WUEs) that can be used to gain insight into high-level comparisons of the productivity and sustainability of alternative farming practices across temporal and spatial scales. The framework is intended as a data aggregation and presentation device. It treats flows of water, biomass and money in a mixed farming system; economic inefficiencies in these flows are tracked as they are associated with a range of NRM indicators.We illustrate the use of the framework, and its place in a larger research programme, by employing it to synthesise the results from a set of modelling analyses of the effect of land use choices on long-term productivity and a range of NRM indicators (frequency of low ground cover, deep drainage, N leaching rates and rate of change in surface soil organic carbon). The analyses span scales from single paddocks and years to whole farms and have been carried out with the APSIM and GRAZPLAN biophysical simulation models and the MIDAS whole-farm economic model.In single wheat crops in one study, different land uses in preceding years affect grain yield primarily by affecting the harvest index. When the scale changes to cropping rotations, the critical factor affecting overall water use efficiency is found to be the proportion of stored soil water that is transpired by crops. When ordinated in terms of their water use efficiencies, a set of 45 modelled rotation sequences at another location are differentiated mainly by the proportion of pasture in the rotation; when rotations are ordinated using key NRM indicators, the proportion of lucerne pasture is the main distinguishing factor. Finally, we show that for whole crop-livestock farms at three different locations across southern Australia, the pattern of water use efficiencies in the most profitable farming systems changes in similar ways as cropping proportion is altered. At this scale, land use choices affect multiple water use efficiency indices simultaneously and commodity prices determine the balance of the resulting economic tradeoffs.Limitations to the use of the WUE framework arising from its relative simplicity are discussed, as are other areas of farming systems research and development to which it can be applied.  相似文献   

Gap formation in Danish beech (Fagus sylvatica) forests of low management intensity: soil moisture and nitrate in soil solution     

Eva Ritter  Lars Vesterdal 《European Journal of Forest Research》2006,125(2):139-150

Soil moisture content (0–90 cm depth) and nitrate-nitrogen (NO₃-N) concentrations in soil solution (90 cm depth) were monitored after gap formation (diameter 15–18 m) in three Danish beech-dominated forests on nutrient-rich till soils. NO₃-N drainage losses were estimated by the water balance model WATBAL for one of the sites. Two forests were non-intervention forests (semi-natural and unmanaged), the third was subject to nature-based management. The study was intended to assess the range of effects of gap formation in forests of low management intensity. In the unmanaged and the nature-based managed forest, soil solution was collected for 5 years and soil moisture measured in the fourth year after gap formation. Average NO₃-N concentrations were significantly higher in the gaps (9.9 and 8.1 mg NO₃-N l⁻¹, respectively) than under closed canopy (0.2 mg l⁻¹). In the semi-natural forest, measurements were carried out up to 29 months after gap formation. Average NO₃-N concentrations in the gap were 19.3 mg NO₃-N l⁻¹. Gap formation alone did not account for this high level, as concentrations were high also under closed canopy (average 12.4 mg NO₃-N l⁻¹). However, the gap had significantly higher N concentrations when trees were in full leaf, and NO₃-N drainage losses were significantly increased in the gap. No losses occurred under closed canopy in growing seasons. Soil moisture was close to field capacity in all three gaps, but decreased under closed canopy in growing seasons. In the semi-natural forest, advanced regeneration and lateral closure of the gap affected soil moisture levels in the gap in the last year of the study.  相似文献   

杭埠河流域土地利用数据库系统的研究与开发   总被引：1，自引：0，他引：1  

雷能忠  马众模  蒋旭东 《中国农学通报》2005,21(5):411-414

土地利用数据是进行流域农业面源污染治理的重要基础资料。以国产地理信息系统软件SupMap作为开发平台建立的杭埠河流域1:5万土地利用数据库系统具有批量数据采集、管理、更新功能,以及运行稳定、安全可靠和很好的可扩展性特点。文章详细介绍了系统数据采集方法、数据组织方式、数据更新和数据库应用系统功能实现。  相似文献   

一种高质量的数字高程模型（DEM）建立方法 ——ANUDEM法   总被引：10，自引：0，他引：10  

张彩霞  杨勤科  段建军 《中国农学通报》2005,21(12):411-411

建立高质量的数字高程模型（DEM）是正确计算坡度、坡向、提取流域地形特征、进行水文分析的前提，因而在研究土壤侵蚀、植被建设和土地利用规划与评价中都具有重要意义。ANUDEM采用迭代有限微分内插技术和地形强化算法，自动去除伪下陷点和生成输入数据错误文件，便于查错改善DEM质量，并减少了去除伪下陷点的编辑或DEM的后处理过程。本文以黄土高原丘陵沟壑区典型小流域为例，利用大比例尺（1:10000）数字化地形图，利用ANUDEM建立DEM，从DEM光照模拟图、回放等高线、提取水系、坡度等方面对建立的DEM的质量进行了评价。研究表明，ANUDEM建立的DEM表面光滑；回放等高线与原等高线符合度高，能更准确地表现地形起伏；由其提取的坡度准确；水系连续完整与地形图上河流一致，适宜水文分析，是一种建立高质量DEM的优良方法。  相似文献