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Quantifying soil organic carbon (SOC) dynamics is critical for monitoring agricultural sustainability and mitigating global climate change. A study was done to investigate the SOC changes between 2003 and 2016 by DeNitrification-DeComposition (DNDC) model in an intensively cultivated region of eastern China, using a detailed high-resolution soil database, which contained 4875 sites (0���20 cm depth) with the sampling density of one sample per km2 in 2003. Results showed the DNDC model had good performance for simulating the SOC dynamics in the study area. Spatial analysis showed that 71% of the study area gained C, whilst 29% maintained their C balance with no C loss in all areas. Results suggested that the current management practice facilitated soil C sequestration in this region although soil type also played an important role. SOC density (SOCD) in lime concretion black soil was significantly higher than those in other soils. The averaged global warming potential ranged from 3865.8 to 7110.8 kg CO2 equivalent ha���1 yr���1 from 2003 to 2016 with CH4 contributing the largest proportion, which might be associated with the high input of fertilizer. Spatially high-resolution estimates of SOC using DNDC can support dual agricultural and carbon management in this region.

This study focused on the effects of vessel and water temperatures on direct injection in internal combustion Rankine cycle engines through experimental and numerical methods. First, a study was carried out with schlieren photography using a high-speed camera for simultaneous liquid–gas diagnoses. Water was directly injected into a constant-volume vessel that provided stable boundaries. We wrote a MATLAB program to calculate spray tip penetration and cone angle from the images. For the further extension of boundary conditions, a numerical model was established and calibrated in AVL-FIRE for the thorough analysis of injection characteristics. Both experimental and numerical results indicated that injection and vessel temperatures have different effects on spray tip penetration. An increase in injected water temperature leads to shorter spray tip penetration, while the spray tip penetration increases with increasing vessel temperature. However, increased injection and vessel temperatures can both decrease the spray cone angle. Moreover, the simulation results also suggested that heat conduction is a main factor in boosting evaporation under top dead center conditions. When the internal energy of water parcels surges, these parcels evaporate immediately. These results are helpful and crucial for internal combustion engines equipped with direct water injection technology.

The engine will consume a large amount of air in the climatic environment facility when the engine is running in the test. The pressure in the chamber may decrease and the temperature in the chamber will change. In order to ensure the continuity and safety of the climatic test, the jet engine make-up air unit (JMAU) will compensate the cold/heat to guarantee the continuous and effective performance of the engine start-up test. Therefore, we should design the brine storage to ensure the supply of the brine.

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We report a case of 50-year-old man with a severe acute ischemic stroke followed by intracerebral hemorrhage and brain abscess due to systemic infection. His initial intracranial radiographic findings were normal but three days later MRI scan of the brain revealed well-defined rounded cystic lesion on the T2-weighted and T1-weighted images in the right basal ganglia; the lesion presented an area of diffusion restriction on DWI; lately the lesion was confirmed to be an early stage of cerebral abscess. A week later the patient was noted to have worsening neurological status and left extremity weakness, and emergency brain CT scan revealed massive intracerebral hemorrhage in the right occipital lobe; he underwent intracranial hematoma evacuation surgery. The hematoma was removed successfully, and the systemic infections were treated with antibiotics.

At the global scale, an increase in urban gardening activities is being observed and the question of produce quality is therefore regularly investigated in relation to pollutant transfer in the environment. The scientific question investigated in the present study was in what way is the presence of arsenic pollution detected in community gardens a public problem and how would each party take ownership of this issue? An interdisciplinary and participative research study “JASSUR” based on both agronomy and risk assessments was conducted in a French collective garden impacted by arsenic pollution in the well water used for irrigation. Gardener surveys and public meetings examined the gardeners’ representations of risk and research solutions for sustainable site management. The theoretical framework of Gilbert which applies a social construction of risk was used. Without an official arsenic limit concentration for vegetables produced in the gardens, a collective risk construction and management process took place. Arsenic total and human bioaccessible concentrations were measured in both vegetables and soil and compared to reference data from a national database to assess the level of health risk. Vegetable quantities produced were obtained in the field from gardeners using harvest booklets. On the basis of a quantitative assessment of the health risk due to produced vegetable consumption, it was concluded that gardening activities could safely continue. However, the regional health authorities forbid the use of the arsenic polluted water, and the wells were permanently closed. By favoring the exchanges between the gardeners and the other stakeholders (researchers and politicians), the arsenic pollution led to structuration in the community of gardeners and permitted a collective construction of risk management.