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Directionally solidified Al2O3/Er3Al5O12 (EAG) eutectic ceramics are characterized by high melting point, improved high-temperature flexural strength, and high fracture toughness. Therefore, they have recently attracted considerable attention as candidates for high-temperature (>1500 °C) structural materials. In this work, directionally solidified Al2O3/EAG eutectic ceramics were prepared by the optical floating zone technique. 2D and 3D microstructures were observed by scanning electron microscopy and X-ray computerized tomography. The effect of thermal gradient and the solidification rate on Al2O3/EAG eutectic microstructure was investigated. The microstructure was completely irregular, exhibiting 3D interconnected microstructure. The size of eutectic microstructure decreased with increasing growth rate. Stable coupled-growth can be obtained when the solidification rate is less than 60 mm/h. Fracture toughness of Al2O3/EAG eutectic ceramics prepared with a withdrawal rate of 40 mm/h, measured by indentation tests, was KIC = 5.7 ± 0.3 MPa m1/2 and the hardness was HV = 14.5 ± 0.4 GPa. Interfaces between Al2O3 and the EAG phases play important role in improving fracture toughness. The characterization of microstructure and mechanical properties of Al2O3/EAG eutectic ceramics may provide guidance for microstructure design and reveal the deformation mechanisms of Al2O3/EAG eutectic ceramics.

This experiment was conducted to assess the comparative effects of dietary antibiotics and oregano essential oil (OEO) addition on growth performance, antioxidant status and intestinal health of broilers. A total of 384 one-day-old broilers were randomly allocated to 4 treatments with 6 replicates of 16 broilers each. The 4 treatments were: an antibiotic-free control diet (control), control + 20 mg/kg colistin sulfate and 20 mg/kg virginiamycin (antibiotics), control + 200 mg/kg natural oregano essential oil (NOEO), and control + 200 mg/kg synthetic oregano essential oil (SOEO). The experiment lasted for 42 d. Results showed that birds fed with OEO had greater (P < 0.05) average daily gain (ADG) and lower (P < 0.05) feed conversion ratio (FCR) than those fed with control diet during d 1 to 21. Besides, birds fed with NOEO had the greatest (P < 0.05) ADG in the four groups during d 22 to 42. The serum oxidative stress parameters showed that OEO improved (P < 0.05) the activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and glutathione reductase (GR) of birds on day 21 and the activity of total antioxidant capacity (T-AOC) of birds on d 42. Relative to control, NOEO increased (P < 0.05) the activity of T-AOC in jejunum and decreased (P < 0.05) the level of malondialdehyde (MDA) in serum and jejunum. Moreover, OEO supplementation increased (P < 0.05) the concentrations of sIgA in duodenum and jejunum, Lactobacillus and total anaerobes in cecum, as well as activities of trypsin, chymotrypsin, lipase and amylase in duodenum, but restrained (P < 0.05) the amount of Escherichia coli. The NOEO supplementation increased (P < 0.05) total anaerobes of broilers on d 42 and the villus height to crypt depth ratio (VH/CD) of ileum. These results suggest that OEO improved antioxidant status and intestinal health of broilers which contributed to the growth performance improvement of broilers. Dietary OEO supplementation can be a promising alternative to antibiotic growth promoters for improving poultry production.

Furrow diking is a type of conservation tillage practice that is widely used throughout the world and has been proved to be effective for preventing runoff and soil loss. However, it is not easy to maintain a stable conservation effect of furrow diking in various environments. Few studies have focused on the effects of rainfall and slope on the integrity and conservation efficiency of furrow diking. Therefore, simulated rainfall experiments were conducted with four rainfall intensities (30 mm/h, 60 mm/h, 90 mm/h and 120 mm/h) and three slopes (2, 4 and 8°) to study the effects of rainfall intensity and slope on soil and runoff production of furrow diking as well as its conservation efficiency. The conservation efficiencies were obtained by comparing furrow diking with up-down slope ridges. The result indicated that as rainfall intensity and slope increased, furrow diking dams may suffer from runoff overtopping resulting in damage and ultimate collapse. During this process, runoff and soil loss increased rapidly, severe rill erosion developed on dams resulting in the loss of the ability of furrow diking to store rainwater and sediment and obvious declines of water and soil conservation efficiencies. This paper established empirical equations to estimate the conservation efficiency of furrow diking under undamaged and damaged conditions. An empirical equation was also presented to estimate the critical rainfall and slope conditions that may cause overtopping, damage or collapse of dams in order to guide the implementation of furrow diking and predict its conservation efficiency.

Land-use and climate changes have impacts on hydrological processes for river basin. In this study, a multi-scenario ensemble streamflow forecast (MESF) method is developed for analyzing the streamflow variation under considering climate and land-use changes, through incorporating CA-Markov model, global climate model (GCM) and Soil and Water Assessment Tool (SWAT) model within a general framework. The advantages of MESF are as follows: (i) it can simultaneously assess the impacts of land-use and climate changes on streamflow; (ii) it can obtain the possible trend and the range of future streamflows through ensemble forecast under multiple scenarios; (iii) based on analysis of streamflow processes under extreme scenarios, it can examine the effects of key factors on streamflow. The MESF method is applied to the upper reaches of the Amu Darya River Basin in Central Asia. Totally 72 scenarios, under different land-use patterns, GCMs and Representative Concentration Pathways (RCPs), are analyzed. Ensemble forecast results reveal that (i) during 2021–2050, the average annual precipitation and the average annual temperature would both increase, but the mean annual streamflow would decrease; (ii) compared to the impact of land-use change, climate change has more obvious effects on the streamflow (with contribution of 78.8%–98.7%); (iii) among all factors of land-use change, glacier melting triggered by climate warming is the most prominent factor; (iv) the peak flow in one year would have a tendency to shift from summer to spring due to the rising temperature and the speeding up snow melt.

Intermetallic compounds (IMCs) growth is often accompanied by void and crack formation. It can reduce the mechanical properties and reliability of solder joints. In this paper, based on the Cu mass transport mechanisms, a theory model is established to analyze the IMC growth behaviors on Cu/Sn/Cu interconnection structures. The influence of IMC dissolution process is considered to investigate the polarity effect of electromigration (EM) on kinetics of IMC growth. Verified by reported experimental data, the model can accurately calculate the thickness of IMC growth under specific temperature and current stressing. The model reveals that during thermal aging, the thickness growth of IMC on Cu–Sn interfaces has a parabolic curve relationship with time. While under current stressing, EM Cu flux in Sn solder accelerates the anode’s IMC growth and motivates the transition of its thickness growth from parabola-like curves to a linear-like relationship. The cathode’s IMC will reach constant thickness with stressing time, which can be primarily determined by the dynamic equilibrium between Cu dissolution flux and chemical Cu flux. When the initial thickness of IMC is larger than this constant, the IMC on the cathode side follows a parabola-like curve to dissolve. Otherwise, it follows a parabola-like curve to increase.

An effective pulse frequency modulation (PFM) control strategy compatible with the charge control is designed for Single Inductor Multiple Outputs (SIMO) DC-DC to deal with its unbalanced loads. Different from the traditional charge control strategy in PFM, it can function without buffer time that degrades the circuit efficiency. Simulation results show that the proposed PFM control strategy can steadily regulate the load-unbalance outputs, even in no load condition. Meanwhile, the PWM/PFM mode conversion can also be achieved.

In this study, an integrated CCA-RF-FA framework (abbreviated as CRFF) is developed for analyzing the streamflow variation in the mountainous watershed. CRFF incorporates cross-correlation analysis (CCA), random forest (RF), and factorial analysis (FA) within a general framework. CRFF can identify the time lag effect in the runoff mechanism (both rainfall and glacier/snow meltwater), tackle the problem of the simulation performance degradation caused by the time lag effect, as well as investigate the individual and interactive effects of meteorological and physical factors on runoff simulation. CRFF is applied to the Amu Darya River Basin (ADRB), a typical mountainous watershed in Central Asia. Bayesian neural network (BNN) and stepwise cluster analysis (SCA) are used for illustrating the advantage of RF in streamflow simulation. The main findings reveal that (i) compared with BNN and SCA, RF has the better simulation capacity; (ii) the time lag effect of heat conditions such as temperature (T) and shortwave radiation (SWR) is weak, with the lag time being less than 30 days; the time lag effect of the precipitation conditions such as snow precipitation rate (SPR) is strong, with a lag time ranging from 30 days to 90 days; (iii) in snow-melting, non-melting and entire periods, T has the dominant impact on the variation of the runoff in ADRB; (iv) the interaction of T and SWR has important effect on the streamflow; SPR can still considerably affect the runoff generation in non-melting period.

An integrated PCA-SCA-ANOVA framework (abbreviated as PSAF) is advanced to analyze the impacts of multiple factors on water-flow variation. PSAF incorporates techniques of principle component analysis (PCA), stepwise-cluster analysis (SCA), and analysis of variance (ANOVA) within a general framework. PSAF cannot only quantify the sensitivity of water flow to individual and interactive factors, but also simulate water flow effectively under different scenarios. A case study of the Aral Sea is conducted to demonstrate the effectiveness and practicability of PSAF. The Nash-Sutcliffe coefficients for calibration and validation are 0.96 and 0.84, respectively. Results reveal that the key impact factors that cause the variability of water flow from the Amu Darya into the Aral Sea are runoff in the upper reach (contributing 53%), agricultural water use (occupying 23%) and water storage in reservoirs (occupying 3%). Results also disclose that runoff in the upper reach and agricultural water use have obvious interaction; the high level of runoff in the upper reach can enhance the negative effects of agricultural water use on water flow. In the future, to recover the water flow from the Amu Darya into the Aral Sea to the level of that in the 1990s (about 8 km3), the decreasing rates of annual agricultural water use and water storage in reservoirs should be controlled at 1.0% and 0.5%, respectively. The findings are helpful for supporting water resources management and restoring the ecological environment of the Aral Sea.

In this study, a MCMC-based maximum entropy copula (abbreviated as MCMC-MEC) method is developed for assessing drought risk under uncertainty. MCMC-MEC has advantages in analyzing the bivariate drought risk (i.e. duration and severity) through runs-theory, improving the fitting processes of drought variables based on maximum entropy, and reflecting the uncertainties in bivariate drought risk assessment through MCMC. Then, MCMC-MEC is applied to the Amu Darya River Basin, a typical arid and semi-arid basin in Central Asia. Results disclose that, during 1935–2015, the study basin experienced about 42 drought events, average duration of each drought was 5 months (severity 4.38), and the most severe drought event lasted for 25.3 months (severity 27.9). Results also reveal that uncertainty in parameter of copula has effects on drought risk, and duration and severity would increase with confidence level of univariate drought probability. At confidence level of 0.9, the bivariate drought risk would be 4%-6% (duration ≥ 7.0 months and severity ≥ 5.8); at confidence level of 0.95, the drought risk would be 1%-2% (duration ≥ 10.0 months and severity ≥ 10.6). During 2005–2015, drought risk for the study basin was increased due to the decreasing precipitation and runoff, and their contribution rates to the drought risk were 55.8% and 44.2%, respectively. The findings are helpful for providing decision support of drought management and disaster prevention.

In this study, an interval double-sided chance-constrained programming (abbreviated as IDCP) method is developed for dealing with uncertainties expressed as interval values and double-sided randomness in both left- and right-hand sides of constraints. The method is applied to planning urban eco-environmental management of Shenzhen (China), where various eco-environmental indicators are used for ensuring ecological security. Through solving the IDCP-based urban eco-environmental management (abbreviated as IDCP-UEM) model, solutions for land-use pattern, industrial structure, system benefit, and ecosystem service value under different probability levels (i.e. p level) have been generated. Then, the conversion of land use and its effect at small regional extent (abbreviated as CLUE-S) model is used for analyzing the spatial characteristic of land-use pattern, which can further optimize the results from the IDCP-UEM model through providing the spatial allocation of land resources. Results reveal that (i) uncertainties existed in the urban ecosystem have significant impacts on system benefit and land-use pattern; (ii) at the end of the planning horizon, the area of forest land would be raised and the expansion of construction land would slow down; (iii) industries of electronic information and machinery manufacturing should be developed because they contribute higher benefit and discharge relatively less pollutant than other industries; (iv) system benefit would be raised and pollutant emissions (e.g., chemical oxygen demand, ammonia nitrogen, and solid waste) would be mitigated over the planning horizon. The findings are helpful for decision makers to gain insights into tradeoffs between eco-environmental protection and urban-economic development.

Copula functions are widely used in multivariate hydrological risk assessment. Incorporation of uncertainty analysis within copula functions can improve the degree of reliability to risk inference. In this study, a Bayesian-copula-based frequency analysis (BCFA) method is developed for supporting multivariate hydrological risk assessment under uncertainty, through integrating copula functions and Markov Chain Monte Carlo (MCMC) into a general framework. BCFA is not only capable of identifying multivariate characteristics of hydrological extreme events, but also useful for assessing multiple uncertain parameters in their dependence structure. BCFA is applied to a real case of flood risk assessment in the Naryn River, a typical high-mountain watershed with high frequency snowmelt flood in Central Asia. Major findings can be summarized: (i) the uncertainty range of joint distribution is mainly influenced by the value of flood variable and the selection of copula function, where the uncertainty range would decreases along with flood variable value; (ii) in a same flood event, the probability of both flood duration and flood volume reaching extreme large values is highest, and the probability of either flood peak or flood duration exceeding a certain threshold is highest; (iii) high peak flows (large than 1828.4 m3/s) are usually accompanied with flood durations less than 24.4 day or flood volumes less than 17.6 × 103 m3·d/s. The findings are helpful for providing decision support of flood management and disaster prevention.

To evaluate the effects of splash erosion on crops, throughfall and splash detachment were measured in different crop-growth stages and rainfall intensities under corn and soybean cover. The relation between splash detachment under the crop canopy and leaf area index and throughfall intensity was analyzed. The characteristics of the spatial distribution of splash detachment under the crop canopy were discussed as well. The results indicated that, compared with bare soil, the average splash detachment rate under the canopy during corn growth was reduced from 77% to 43%, with an average of 68% approximately, while a soybean canopy can reduce the splash detachment rate from 77% to 48% with an average of 61% approximately during the growth stage. The splash erosion detachment rate increased significantly with increasing leaf area index and rainfall intensity. The throughfall was concentrated in the centers of rows as crop grows, and a sharp increase in the splash detachment rate was caused by concentrations of throughfall under the canopy, which resulted in uneven distribution of splash detachment. The spatial distributions of splash detachment depended on the spatial distributions of throughfall under the crop canopy. The change in throughfall intensity under the canopy was the main reason for the variation in splash detachment. The reduction of kinetic energy because of interception by the crop canopy contributed to a decrease in splash erosion. However, large raindrops formed at the tips and edges of leaves can generate substantial erosion, and this part of the splash may become the main portion of splash erosion under the canopy. These results indicated that continuous and concentrated raindrops impacted splash detachment and caused its uneven distribution under crop cover.

The aim of this study was to investigate the association between three common SNPs (-1082A/G, -819T/C, and -592A/C) in the interleukin 10 (IL-10) gene, and the development of coronary artery disease. Between January 2013 and December 2014, 272 patients with coronary artery disease and control subjects (each) were recruited for this study from the Huaihe Hospital of Henan University. The IL-10-1082A/G, -819T/C and -592A/C gene polymorphisms were analyzed using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. Logistic regression analyses revealed an association between the AA and GA+AA genotypes of IL-10-1082G/A and an elevated risk of coronary artery disease, compared to the GG genotype [adjusted odds ratio (OR) = 2.31 and 1.49; 95% confidence interval (CI) = 1.29-4.19 and 1.04-2.12, respectively]. The AG+GG genotype was associated with a moderately increased risk of coronary artery disease in smokers (adjusted OR = 2.74; 95% CI = 1.01-3.01). In conclusion, the AA and GA+AA genotypes of IL-10-1082G/A were associated with an elevated risk of coronary artery disease; the IL-10-1082G/A gene polymorphism also interacted with the tobacco smoking habits, contributing to the development of coronary artery disease.

The aim of this study was to investigate the protective effect of necrostatin-1 on myocardial tissue of acute myocardial infarction (AMI) rats and to provide a basis for necrostatin-1 for the treatment of acute myocardial infarction. AMI rats (45) were established by ligating the anterior descending branch of the left coronary artery. The rats were randomly divided into the model group and necrostatin-1 low-dose and high-dose groups. The control group rats (15) underwent the sham operation. The rats in the necrostatin-1 low-dose and high-dose groups were injected with 1 and 4 mg/kg necrostatin-1, respectively, via the tail vein. The rats in the control and model groups were injected with isometric dimethyl sulfoxide, once daily, for 3 consecutive days. The levels of RIP1 and RIP3 mRNA and phosphorylated protein in the myocardial tissue of rats were detected by real time polymerase chain reaction and western blot. The myocardial infarct size was detected by tetrazolium chloride. Compared with that in the control group, the levels of RIP1 and RIP3 mRNA and phosphorylated protein significantly increased in the myocardial tissue of model group rats, necrostatin-1 low-dose group, and high-dose group. The levels of RIP1 and RIP3 mRNA and phosphorylated protein in the myocardial tissue of rats in the necrostatin-1 low-dose and high-dose groups decreased significantly compared with that in the model group (P < 0.05). The levels of RIP1 and RIP3 mRNA in the myocardium of the high-dose group rats were significantly lower than those of the low-dose group rats (P < 0.05). The myocardial infarct sizes significantly increased in model, low-dose, and high-dose group rats. The apoptotic level of myocardial cells significantly decreased in the low-dose group and high-dose group after treatment with necrostatin-1 but was still higher than that of the control group (P < 0.05). In conclusion, necrostatin-1 can inhibit myocardial tissue apoptosis and necrosis in acute myocardial infarct rats and has a protective effect on myocardial tissue.