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Modern crop production practices are now recognized as being responsible for a significant volume of greenhouse gas emissions. Here, an analysis was undertaken to quantify crop production-related greenhouse gas emissions in China over the period 1991–2015, using Kaya's equation to identify its drivers. The Logarithmic Mean Divisia Index method was adopted to separately quantify the contributions of the efficiency, structure, economy and labor factors. The analysis identified that the efficiency, structure and labor factors acted to reduce greenhouse gas emissions of 455.93, 49.42, 98.75 million tons of carbon dioxide equivalents, respectively, while the economy factor contributed to increase of 637.30 million tons of carbon dioxide equivalents. On a regional basis, the contributions to the national greenhouse gas emissions differed, ranging from −8.24 to 20.86 million tons of carbon dioxide equivalents. Furthermore, the influence of efficiency, structure, economy and labor factors also varied significantly by region. For each region, the management of different factors or combinations of these would be necessary in order to decrease the greenhouse gas emissions in the future: for the northern, north-western and north-eastern regions, it was the efficiency, structure and labor factors; for the eastern region it was the economy factor; for the central-southern region it was the economy and the labor factors; and for the south-western region it was all four factors. Regarding the effect of the efficiency factor, controlling this requires the reduction of chemical fertilizer usage and submerged irrigation time, and the selection of good varieties. With respect to the structure factor effect, the optimization of the agriculture structure is required, particularly in Gansu, Hainan and Shanghai. As for the economic factor, managing its effect requires a moderate economic growth rate with a higher quality of economic development, and the acceleration of the development of agricultural science and technology innovation, guidance and promotion. Finally, the labor factor effect may be controlled with the improvement of the level of agricultural intensification. This study identified, decomposed and quantified the driving factors of the national and regional crop production-derived greenhouse gas emissions and provided practice ways for greenhouse gas inhabitation in China. Image 1 • We identified the drivers of crop production-derived GHG emission in China. • Efficiency, structure and labor factors acted to reduce GHG emission. • The economy contributed to increases in GHG emission. • National-level driving forces of GHG emission changed dynamically over time. • Contributions of regions on national GHG emission differed from each other. [ABSTRACT FROM AUTHOR]

Engineering practices indicate that stratum hydraulic conductivity (SHC) has a significant influence on deep excavations. However, this influence has been ignored in previous studies with undrained analyses. In this study, a numerical model, combined with the verified hydromechanical coupled method, is established to investigate the effect of SHCs on the performances of deep excavations. Excavation deformation, pore-water pressure, lateral pressure, and the stress evolution process are presented, respectively, to illustrate these influences. In addition, the model of a beam on an elastic foundation is employed to interpret the influential mechanism of SHCs on excavation deformations. Analysis results indicate that excavation deformations increase significantly with the increase in SHCs from 1 × 10−7 to 1 × 10−5 cm/s (i.e., the range of SHCs of soil containing silt). The influence of SHCs on excavation deformations is mainly attributed to the variation of effective stress levels on the excavated side. As SHC increases, the change in the resultant force of the total stress acting on the retained side of the wall, as loads, can be ignored, while the resultant force of the effective stress acting on the excavated side of the wall, as resistances, decreases dramatically. These findings emphasize the importance of accurate determination of the SHC of strata containing silt. Engineering practices indicate that stratum hydraulic conductivity (SHC) significantly affects the performances of deep excavations in Shanghai soft deposits. Constructions in the first aquitard (AdI) have been involved in the many deep excavations in Shanghai, China, and therefore, identifying the effects of the SHC of AdI on deep excavations can further ensure the safety of constructions. In this study, it is found that excavation deformations increase significantly as the SHC of AdI increases from 1 × 10−7 to 1 × 10−5 cm/s (i.e., the SHCs in soil containing silt). This finding indicates that valuing the SHC of AdI containing silt requires utmost caution, and adopting appropriate methods such as dewatering can significantly decrease excavation deformations. [ABSTRACT FROM AUTHOR]

Acute renal failure (ARF) is a common complication in hospitalized patients, but little is known about the epidemiology of ARF in China. In this study, we performed a prospective examination of the cause, prognosis, and risk factors associated with ARF at a hospital in Shanghai, China. We considered all ARF patients who were admitted to our hospital from December 2003 to December 2006. Among the 320 ARF patients, 135 (42.2%) were over the age of 60. Sepsis, heart failure, and nephrotoxic drug use were the leading causes of ARF. The overall mortality rate was 31.9%, and mortality rate was significantly higher among the elderly. Logistic regression indicated that heart failure, respiratory failure, and malignant cancer were risk factors independently associated with poor prognosis. In this Shanghai hospital, there was a high incidence and mortality rate of patients hospitalized with ARF. The prognosis of patients who underwent renal replacement therapy was better than those who were treated more conservatively. [ABSTRACT FROM AUTHOR]