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Since the 1990s, the climate in the Amur River Basin (ARB) has changed, and large-scale wetlands in the region have been reclaimed for paddy fields. The study of the influence of climate change and agricultural expansion on groundwater storage is of great significance to the evaluation of regional water resource balance and the promotion of ecological protection and agricultural development. In this work, the groundwater storage anomaly (GWSA) in the ARB and its drivers were analyzed for the period 2003–2016 using Gravity Recovery and Climate Experiment (GRACE) satellite data, a Global Land Data Assimilation System model, and in situ observations of groundwater levels. Results indicated that 1) the GWSA in the ARB increased at a rate of 2.0–2.4 mm/yr from 2003 to 2016; the GWSA in the upper reaches of the ARB increased, whereas the GWSA in the middle and lower reaches decreased during the study period. 2) The GWSA in the middle and lower reaches of the ARB was greatly influenced by temperature (Tmp) and evapotranspiration (ET). Tmp was positively correlated with GWSA, whereas ET was negatively correlated with GWSA (p < 0.05). 3) Extreme rainfall had a delayed effect on groundwater recharge. Wetland degradation and agricultural development were the main factors causing the decrease of the GWSA in the middle and lower reaches of the ARB. In summary, temperature and evapotranspiration affect groundwater storage by regulating the water–heat balance, wetland reclamation reduces the regional storage capacity, and the irrigation required for reclaimed farmland is the main source of groundwater loss.

Objective(s): As a multifunctional molecule, NO has different effects on liver injury. The present work aimed to investigate the effects of Nos2 knockout (KO) on acute liver injury in aged mice treated with carbon tetrachloride (CCl4). Materials and Methods: The acute liver injury model was produced by CCl4 at 10 ml/kg body weight in 24-month-old Nos2 KO mice and wild type (WT) mice groups. The histological changes, transaminase and glutathione (GSH) contents, and the expressions of liver function genes superoxide dismutase (SOD2) and butyrylcholinesterase (BCHE), as well as apoptosis- and inflammation-associated genes were detected at 0, 6, 16, 20, 28, and 48 hr, respectively. Results: Compared with WT aged mice, there are more fat droplets in liver tissues of Nos2 KO aged mice, and the serum levels of ALT and AST were elevated in the KO group; in addition, there was a decrease in the expression of SOD2 and BCHE and GSH content at multiple time-points. Furthermore, the expression of apoptosis protein CASPASE-3 was elevated from 20 to 48 hr, the same as CASPASE-9 at 28 and 48 hr and pro-apoptotic protein BAX at 6 and 28 hr, while the expression of apoptosis inhibitory protein BCL2 declined at 6 and 28 hr; at the same time the mRNA expressions of genes related to inflammation were increased at different extents in liver extracts of Nos2 KO aged mice. Conclusion: Nos2 KO exacerbated liver injury probably by elevated oxidative stress, apoptosis and inflammation response in CCl4-induced aged mice liver intoxication model.

With the development of electric electron technology and controlling technology, controller for driving permanent magnet synchronous motors is used widely. The using of a controller can expand the motor speed range and improve motor runtime performances. However, the output current of a controller contains lots of time harmonics that will have bad influences on motor torque and losses. In order to analyze the influences of the time harmonics on the motor performances, different time harmonic currents were injected into the motor armature. Taking a 750 W, 250 r/min permanent magnet synchronous motor with hybrid magnet poles (HPPMSM) as an example, the 2-D finite model was established. On this basis, the torque ripple and eddy current losses of permanent magnets with different time harmonics were obtained. The influences of time harmonics on motor torque ripple and eddy current losses were determined, and the impacting mechanism was revealed. The analyses may be helpful for the optimal design of HPPMSM.

A great research effort addressed the effect of plant litter decomposition on nutrient cycling in terrestrial and aquatic ecosystems.Environmental factors such as temperature and moisture content related to the decomposition process have been widely studied,and among the hydrological condition is more important and has quite complicated influence.In the present study,we investigated the effects of water conditions on decomposition and nutrient(N and P) dynamics of Carex lasiocapa litters using litter bag method in the Sanjiang Plain of Northeast China.The litter decomposition study was carried out in a typical dish-shaped pit along a water table gradient from May in 2009 to May in 2010.60 nylon bags(approx 1mm diameter) with 8g C.lasiocapa litters were placed near the soil surface or the grass layer in the marsh under unflooded or flooded conditions,with 12 under every water condition.3 bags in each site were taken back to the laboratory every time and then the mass losses and nutrient elements(N and P) contents were analyzed.By the end of decomposition,mass loss of C.lasiocapa litters was 34.99% and 27.28% under non-waterlogging and seasonally inundated conditions,respectively.In the permanently inundated conditions,with increased water table,litter mass loss ranged from 26.99% to 30.67%.The results showed that during the growing season(from May to September),C.lasiocapa litter decayed quickly in the flooded conditions.With increased water table gradient,the mass losses were 16.09%、24.25%、23.53% and 26.60% in non-waterlogging,seasonally inundated and permanently inundated condition,respectively.However,during the non-growing season,though higher water table accelerated the C.lasiocapa litter decomposition slightly in the inundated environment,flooded conditions significantly inhibited the litter decay compared to the dry condition(P0.05).With increased water table gradient,the litter mass losses were 18.90%,3.02%,3.46% and 4.03% in non-waterlogging,seasonally inundated and permanently inundated conditions,respectively.In the growing season,litter N concentration and total N content increased gradually in the early 122 days of decomposition.Waterlogging conditions enhanced litter N immobilization,and litter N concentration under the deepest standing water condition was significantly higher than that under the dry condition(P0.05).However,litter N concentration and total N content declined in the freeze-thawing season,and all the litters under flooded conditions released N after 122 days of decomposition.In addition,seasonal inundated conditions significantly inhibited litter N accumulation,and litter N content was significantly lower than the initial value after 360 days of decomposition(P=0.01).Moreover,litter P content significantly increased after 61 days of decomposition,especially in the flooding conditions.However,litter P enrichment had no correlation to water table depths.For all litter decomposition treatments,litter P concentration and total P content decreased after one year of decomposition,but did not vary with water table(P0.05).Our results suggested that,in the Sanjiang Plain of Northeast China,the effect of water table on litter decomposition varied with decomposition stage,and flooding conditions stimulated litter decomposition in the growing season in the freshwater marshes.

The responses of soil enzyme activity of freshwater marsh, microbial biomass carbon (MBC), dissolved organic carbon (DOC) and aboveground biomass to water gradients were studied with Carex lasiocarpa pot culture experiment. The relationships between soil enzyme activity and MBC, DOC and aboveground biomass were discussed. The water gradients were W1, 15 cm; W2, −5 cm; W3, −5–5 cm; W4, submerged. The results indicated that acid phosphatase, invertase and urease activities were decreased with the increase of water level, while catalase activity was increased with moisture content increasing. Drying-wetting alternation (W3) increased soil enzyme activities if compared with W1. MBC content followed the order of W3 > W1 > W2 > W4, and the activities of invertase, urease and catalase were significantly positively correlated with MBC (p W1 > W3 > W2, and the activities of urease and acid phosphatase were most significantly negatively correlated with DOC (p < 0.01). In addition, drying-wetting alternation promoted the growth of Carex lasiocarpa. When water submerged plants, the growth of Carex lasiocarpa was significantly inhibited. The aboveground biomass was positively related to soil enzyme activities. There were close relationships between the activities of invertase, urease and catalase and the growth situation of Carex lasiocarpa.

In this paper, the design for a dual core FFT processor based on CORDIC algorithm is presented. This design extracts the 2-base successions as the foundation, takes the FFT butterfly-shaped arithmetical unit as the object, uses the CORDIC algorithm superiority in the vector computation to simply the revolving factor calculation, and employs the assembly line technology to enhance the turnover rate for the whole system. This FFT processor has many characteristics with the simple hardware architecture, flexible disposition, low component coupling, high precision and stable running, can perform the high speed fixed-point real-time FFT operation. Experiment carried on the gate level simulation in Altera chip EP2C35F672C6 shows that this design can satisfy the 50MHz system clock.