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Rain-fed crops are a major crop type, and their water use is extremely vulnerable to climate change. Studying the water requirement characteristics of rain-fed crops in different growth stages and associated climatic driving factors is of great significance for sustainable crop production. The water footprint (WF) of crops can comprehensively reflect the type and quantity of water consumption during the crop growth period. Previous studies have focused on quantifying the crop WF throughout the growth period, and less attention has been given to quantifying the crop WF in different growth stages. This study quantified the WFs of rain-fed maize and associated climatic driving factors in five growth stages from 1996 to 2018 in Northeast China. The results show that (1) the WF of rain-fed maize in each growth stage showed distinct differences. The highest WF occurred in the tasseling-milky growth stage, whereas the lowest WF occurred in the sowing-emergence growth stage. (2) The variation trends of maize WF in different growth stages were heterogeneous across Northeast China. The declining trends were mainly distributed in the southwest, while increasing trends were mainly distributed in the east in most growth stages. (3) Sunshine hours and temperature had a greater impact on the maize WF in most growth stages. The impacts of other climatic factors on the WF of rain-fed maize differed among different growth stages. Precipitation contributed much more to the variation in maize WF in early growth stages, relative humidity had the greatest impact on the WF of maize in the jointing-tasseling growth stage, and wind speed played a major role in the variation in the maize WF at the milky-mature growth stage. Management measures should be adjusted to alleviate the impact of climatic conditions on crop water consumption in different growth stages according to the results. • Water footprint (WF) of rain-fed maize in different growth stages was analyzed. • The highest WF was in tasseling-milky stage and the lowest in sowing-seeding stage. • Sunshine hours and temperatures had a greater impact on WF in most growth stages. • Feasible measures to reduce the impact of climatic factors on WF were discussed. [ABSTRACT FROM AUTHOR]

Grey water footprints (GWFs) can be used as an indicator to describe the influence of diffuse pollution on water environments and identify major contaminants. To improve the calculation of GWF, we conducted a field experiment with combinations of different slopes and fertilizer types on maize production in the black soil region of China. The goals of this study were to determine the actual amount of water used to dilute the pollutants; to explore the changes in the GWF under different slopes and fertilization types; and to identify the most critical pollutants and determine if they are consistent with those identified in previous studies. The results showed that the average GWFs of maize production were much different in 2016 and 2017. The GWFs of the 5° plots were much larger than those of the 1° plots and 3° plots, and the GWFs of the mineral fertilizer plots were larger than those of the organic manure plots in most cases. The loss rates of total nitrogen (TN) in the mineral fertilizer plots and the organic manure plots were all 0.2% in 2016 and 2.7% and 3.1% in 2017, respectively, which was much lower than 10% as reported in most articles. The most frequent critical pollutant was total nitrogen (TN), while total phosphorus (TP) and chemical oxygen demand (COD) were also critical pollutants in some cases, which differed somewhat from the results of previous studies. The uneven annual distribution of rainfall led to large interannual differences in the size of the GWFs. Therefore, using field observations, pollutant loss from agricultural ecosystems could be determined in line with local conditions, which should provide a reference for relevant measures to control diffuse pollution. [ABSTRACT FROM AUTHOR]

Increasing evidence suggests that inflammation and apoptosis are involved in the development of acute myocardial ischemia (AMI). Nucleotide-binding oligomerization domain (NOD)-like receptors (NLRs) have recently been identified as key mediators of inflammatory responses. The aim of this study was to explore the specific role and the underlying regulatory mechanism of NLRX1 in myocardial ischemic injury. The results show that NLRX1, located in mitochondria, was significantly down-regulated in AMI tissues and hypoxia-induced H9c2 cells. Overexpression of NLRX1 markedly decreased the levels of lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB) and cardiac troponin-I (cTn-I), down-regulated the production of IL-1β，IL-18 and IL-6, and reduced apoptosis induced by hypoxia. Conversely, depletion of NLRX1 with small interfering RNA (siRNA) aggravated hypoxia-induced ischemic injury. We then demonstrated that NLRX1 was associated with the mitochondrial antiviral signaling protein (MAVS) and regulated MAVS-dependent NLRP3 inflammasome activation. NLRX1 overexpression significantly inhibited hypoxia-induced up-regulation of MAVS, NLRP3 and Caspase-1 expression. Additionally, the negative effects of NLRX1 overexpression on hypoxia-induced inflammatory factor production and apoptosis were neutralized by MAVS or NLRP3 overexpression. Taken together, these findings suggest that NLRX1 may function as a cardiac-protective molecule in myocardial ischemic injury by repressing inflammation and apoptosis; the biological effects appear to be mediated by the inhibition of MAVS-dependent NLRP3 inflammasome activation. [ABSTRACT FROM AUTHOR]