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The amorphous/crystalline (A/C) dual-phase structure is a new design strategy to improve the comprehensive performance of Mg alloys. However, the regulation mechanism of the amorphous phase size of the dual-phase Mg alloys is still unclear. Here, the mechanism and size effect of solid-state amorphization of the dual-phase Mg alloys is investigated using molecular dynamics/Monte Carlo simulations. The results indicate that the degree of solid-state amorphization of the dual-phase Mg alloys depends on three factors: the original size of amorphous phase, the diffusion of rare earth element Y, and A/C interface (ACI). The degree of solid-state amorphization of the alloys exhibits a significant size effect on the original size of amorphous phase. Except for the two models with the smaller original size of the amorphous phase, the degree of solid-state amorphization of the alloys decreases significantly with the increase of the original size of amorphous phase. It is worth noting that after relaxation, as the original size of amorphous phase increases, the distribution of Y atoms in the amorphous phase undergoes a transition from uniform distribution to segregation, and the larger the original size of amorphous phase, the more obvious the segregation phenomenon becomes. The results indicate that the segregation of Y atoms in the amorphous phase suppresses the solid-state amorphization of the alloys. The results show that the segregation of Y atoms in the alloys requires a larger original size of the amorphous phase and the presence of ACI, both of which are essential.

We hypothesised that adding a combination of fibrolytic and amylolytic enzymes to the diet of early-lactation dairy cows would improve rumen enzyme activity and bacterial diversity, promote energy metabolism, and benefit milk production in cows. Twenty multiparous early-lactation (90 ± 5 d) Holstein cows with similar body conditions were randomly allocated to control (CON, n = 10) and experimental (EXP, n = 10) groups in a completely randomised single-factor design. The CON was fed only a basal total mixed ration diet, and the diet of the EXP was supplemented with a combination of fibrolytic and amylolytic enzymes at 70 g/cow/d (cellulase 3 500 CU/g, xylanase 2 000 XU/g, β-glucanase 17 500 GU/g, and amylase 37 000 AU/g). The experiment lasted 28 days, with 21 days for adaptation and 7 days for sampling. Enzyme addition increased the activity levels of α-amylase and xylanase, and the ammonia-N concentration (P 0.1%) or genus (richness > 1%) composition between the CON and EXP groups (P > 0.05). A tendency of difference was found between CON and EXP (R = 0.22, P = 0.098) in principal component analysis. Ten genera showed different abundances across the CON and EXP groups (linear discriminant analysis effect size, linear discriminant analysis > 2). EXP increased the ratio of albumin to globulin and the concentrations of total cholesterol and low-density lipoprotein cholesterol (P

The saline character of water imposes restrictions on plant growth and survival in the Taklamakan Desert, China. Experiments were conducted on woody plant species, Tamarix ramosissima, Populus euphratica, and Haloxylon ammodendron grown under different levels of salinity to elucidate their adaptation to a saline environment. H. ammodendron accumulated large amounts of Na+ and Cl- in leaves. P. euphratica restricted redundant Na+ and Cl- transport to the shoots treated with lower NaCl concentrations. Na+ in leaves of T. ramosissima accumulated significantly only under higher NaCl concentrations (≥ 200 mM NaCl). The analyzed plants' exposure to high saline concentrations induced oxidative stress as evidenced by the increase of H2O2 and malondialdehyde and changes in photosynthetic pigments, gas-exchange characteristics, and antioxidant enzyme activities. T. ramosissima and H. ammodendron exhibited a greater ability to adapt to saline-induced oxidative stress due to more efficient antioxidant enzyme system to prevent oxidative damage.

The effect of Al stress on leaf pigment contents, chlorophyll (Chl) a fluorescence transient, and leaf gas exchange of Citrus sinensis and Citrus grandis were investigated in sandy culture with nutrient solution (control) or supplemented by 0.5 mM AlCl3.6H2O (Al toxic) for 54 weeks. We found a significant decline of Chl a, carotenoids (Car), Ch a/b, and Car/Chl (a+b) in C. grandis caused by Al stress. Except the significant increase of Car/Chl (a+b), no remarkable difference was found in C. sinensis. The Al-induced downregulation of CO2 assimilation was related to the imbalance of reduction and oxidation of primary quinone acceptor of PSII in two Citrus species. Compared to C. grandis, increasing ratio of Car/Chl (a+b) for photooxidation protection and decreasing inhibition of electron transfer contributed to electron conversion efficiency maintenance of PSII under Al stress in C. sinensis, a relatively Al-tolerant species.

The development of digestive organs and the establishment of gut microbiota in pullets play an important role throughout life. This study was conducted to investigate the effects of Bacillus subtilis (BS) on growth performance, intestinal function and gut microbiota in pullets from 0 to 6 weeks of age. Hy-line Brown laying hens (1-day-old, n = 504) were randomly allotted into four diets with a 2 × 2 factorial design: (1) basal diet group (control); (2) antibiotics group (AGP), the basal diet supplemented with 20 mg/kg Bacitracin Zinc and 4 mg/kg Colistin Sulphate; (3) BS group, the basal diet supplemented with 500 mg/kg BS and (4) mixed group, the basal diet supplemented with both AGP and BS. As a result, when BS was considered the main effect, BS addition (1) reduced the feed conversion ratio at 4 to 6 weeks (P < 0.05); (2) decreased duodenal and jejunal crypt depth at 3 weeks; (3) increased the villus height : crypt depth (V : C) ratio in the duodenum at 3 weeks and jejunal villus height at 6 weeks and (4) increased sucrase mRNA expression in the duodenum at 3 weeks as well as the jejunum at 6 weeks, and jejunal maltase and aminopeptidase expression at 3 weeks. When AGP was considered the main effect, AGP supplementation (1) increased the V : C ratio in the ileum at 3 weeks of age; (2) increased sucrase mRNA expression in the duodenum at 3 weeks as well as the ileum at 6 weeks, and increased maltase expression in the ileum. The BS × AGP interaction was observed to affect average daily feed intake at 4 to 6 weeks, and duodenal sucrase and jejunal maltase expression at 3 weeks. Furthermore, dietary BS or AGP addition improved caecal microbial diversity at 3 weeks, and a BS × AGP interaction was observed (P < 0.05) for the Shannon and Simpson indexes. At the genus level, the relative abundance of Lactobacillus was found to be higher in the mixed group at 3 weeks and in the BS group at 6 weeks. Moreover, Anaerostipes, Dehalobacterium and Oscillospira were also found to be dominant genera in pullets with dietary BS addition. In conclusion, BS could improve intestinal morphology and change digestive enzyme relative expression and caecum microbiota, thereby increasing the efficiency of nutrient utilization. Our findings suggested that BS might have more beneficial effects than AGP in the study, which would provide theoretical evidence and new insight into BS application in layer pullets.

The spectrum effects on toroidal rotation braking, induced by n = 1 resonant magnetic perturbations (RMPs) in the discharges with $q_{95} = 4.1$ and $q_{95} = 5.1$ , are studied in the EAST tokamak. Here n is the toroidal mode number, RMP spectrum is varied by scanning $\delta\phi_\mathrm{UL} $ , the phase difference between the upper and lower rows of RMP coils. The toroidal rotation changes periodically with the periodic $\delta\phi_\mathrm{UL} $ scanning and such an effect is stronger in the discharge with lower $q_{95} = 4.1$ . The spectrum dependence of the neoclassical toroidal viscosity (NTV) torque, modeled by NTVTOK based on the magnetic perturbation obtained from MARS-F calculation, agrees well with that of the experimentally observed braking torques in both discharges. The modeled NTV torque is stronger in the discharge with lower q _95 , which also agrees with the observations. The comparisons between the spectrum dependence of the NTV and magnetic perturbations show that the resonant mode of magnetic perturbations near the plasma edge mainly contribute the NTV torque. These agreements between modeling and experiments highlight the capability of NTV theory in explaining the experimental observation in the EAST tokamak.

The Na and Al dual substitution Na0.5Bi0.5TiO3 samples were synthesized by the conventional solid-state reaction method. The oxygen ion conductivity and migration in the Na0.54Bi0.46Ti1−xAlxO2.96−x/2 (x = 0.02, 0.04, 0.06 and 0.08) samples were investigated. The grain conductivity and relaxation activation energy of the Na0.54Bi0.46Ti1−xAlxO2.96−x/2 samples show the trend of declining-rising-declining with the increase of Al-doped content. The highest grain conductivity can arrive at 0.0016 S/cm for the Na0.54Bi0.46Ti1−xAlxO2.96−x/2 (x = 0.06) sample at 673 K and the corresponding activation energy is about 0.80 eV, which are the lowest results of oxygen ion diffusion in the Na0.54Bi0.46Ti1−xAlxO2.96−x/2 (x = 0.02, 0.04, 0.06 and 0.08) samples. The mobile oxygen vacancy content decreases with increasing Al-doping content in the Na0.54Bi0.46Ti1−xAlxO2.96−x/2 compounds. The sudden change of grain conductivity in NBT-Na4Al6 sample may be from the lower activation energy and better oxygen vacancy mobility. These results are helpful to improve the electrical performance by doping methods. Keywords: Oxide ionic conductivity, Dielectric relaxation, Oxygen vacancy mobility, Dual substitution

We present the first experimental determination on the spectroscopic amplitudes (SAs) for the α-cluster in the B11 ground state via the Li7(Li6,d)11B reaction using a high-precision magnetic spectrograph. This is believed to have a strong effect on the studies of α-induced reactions which are crucial in nuclear astrophysics. It is found that the previous SAs of B11 from shell model calculations cause overestimations of up to 23% for the C12(α,γ)16O SE2(300) factor and up to 34% for the C13(α,n)16O S(190) factor with respect to the results from the present experimentally determined SAs. Due to the importance of these two reactions, for example the uncertainty in the C12(α,γ)16O cross section at Ec.m. = 300 keV is required to be better than 10% by stellar modeling, the new S-factors could result in a potential influence on the astrophysical network calculations.

To meet the miniature requirement, a frequency modulated continuous wave synthetic aperture radar (FMCW SAR) puts tight constraint on the compactness, which causes the interference of narrow band noise. The aim of this study is to suppress the strong noise for an FMCW SAR. First, the quantitative analysis of the noise is performed. It is found that a strong spurious noise of the analog-to-digital converter (ADC) is introduced from interferences and significantly affects the image quality; the other noise components are sufficiently small, thus having ignorable influences. Then, a Fast Fourier Transform (FFT) based method of noise suppression is proposed to eliminate the ADC strong spurious noise, adopting an ADC and a field programmable gate array (FPGA). Finally, using the real Ku-band FMCW SAR data, the level of the noise components is measured and the effectiveness of the proposed noise suppression method is validated. The results show that the measured noise level coincides with the theoretical noise level, and the proposed noise suppression method effectively eliminates the ADC strong spurious noise.

Accumulating evidence has indicated the importance of cancer stem cells in carcinogenesis. The goal of the present study was to determine the effect of low-dose cisplatin on enriched liver cancer stem cells (LCSCs). Human hepatoblastoma HepG2 cells were treated with concentrations of cisplatin ranging from 1 to 5 μg/mL. Cell survival and proliferation were evaluated using a tetrazolium dye (MTT) assay. LCSCs were identified using specific markers, namely aldehyde dehydrogenase-1 (ALDH1) and CD133. The percentage of ALDH1+ or CD133+ cells was examined by flow cytometric analysis. The expression of ALDH1 and/or CD133 in HepG2 cells was determined by immunocytochemical analysis. Low-dose cisplatin treatment significantly decreased cell survival in HepG2 cells after 24 or 72 h. However, the percentage of LCSCs in the surviving cells was greatly increased. The percentage of ALDH1+ or CD133+ cells was increased in a time- and dose-dependent manner after treatment with 1-4 μg/mL cisplatin, whereas 5 μg/mL cisplatin exposure slightly reduced the number of positive cells. These findings indicate that low-dose cisplatin treatment may efficiently enrich the LCSC population in HepG2 cells.

Bone morphogenetic protein 2 (BMP2) and basic fibroblast growth factor (bFGF) have been shown to exhibit a synergistic effect to promote bone repair and healing. In this study, we constructed a novel adenovirus with high coexpression of BMP2 and bFGF and evaluated its effect on osteogenic differentiation of goat bone marrow progenitor cells (BMPCs). Recombinant adenovirus Ad-BMP2-bFGF was constructed by using the T2A sequence. BMPCs were isolated from goats by density gradient centrifugation and adherent cell culture, and were then infected with Ad-BMP2-bFGF or Ad-BMP2. Expression of BMP2 and bFGF was detected by ELISA, and alkaline phosphatase (ALP) activity was detected by an ALP assay kit. In addition, von Kossa staining and immunocytochemical staining of collagen II were performed on BMPCs 21 days after infection. There was a high coexpression of BMP2 and bFGF in BMPCs infected with Ad-BMP2-bFGF. Twenty-one days after infection, ALP activity was significantly higher in BMPCs infected with Ad-BMP2-bFGF than in those infected with Ad-BMP2. Larger and more mineralized calcium nodules, as well as stronger collagen II staining, were observed in BMPCs infected with Ad-BMP2-bFGF than in those infected with Ad-BMP2. In summary, we developed a novel adenovirus vector Ad-BMP2-bFGF for simultaneous high coexpression of BMP2 and bFGF, which could induce BMPCs to differentiate efficiently into osteoblasts.

The impacts of tillage system (conventional tillage and no-tillage) and residue management (0, 50, and 100%) on soil properties and soil microbial community structure were determined in the Fengqiu State Key Agro-Ecological Experimental Station, North China. The microbial community structure was investigated by phospholipid fatty acid (PLFA) profiles. The results showed that tillage had significant effects on soil properties and soil microbial communities. In no-tillage (NT), microbial biomass carbon (MBC), total N, microbial biomass carbon/soil organic carbon (MBC/SOC), total microbes, and arbuscular mycorrhiza fungi increased, while actinomycetes, G+/G- bacteria ratio and monounsaturated fatty acids/saturated fatty acids (MUFA/STFA) decreased, compared with those in conventional tillage (CT). Residue had a significant positive effect on C/N ratio and MUFA/STFA. Canonical correspondence analysis indicated that tillage explained 76.1%, and residue management explained 0.6% of the variations in soil microbial communities, respectively. Soil microbial communities were significantly correlated with MBC, total N, C/N ratio and MBC/SOC. Among the six treatments, NT with 100% residue application obviously improved soil microbiological properties, and could be a proper management practice in the Huang-Huai-Hai Plain of China.

This paper addressed the spatial distribution characteristics of organic matter, total nitrogen, extractable phosphorus and extractable potassium in agricultural soils of Northeast China. The related factors were explored using geostatistics and geographic information systems. The results showed that the log-transformed data of the four soil nutrients followed a normal distribution. Soil extractable phosphorus had a higher coefficient of variation. The experimental variogram of the log-transformed data of soil organic matter, total nitrogen and extractable phosphorus was fitted with an exponential model, while soil extractable potassium was fitted to a spherical model. Soil samples from smaller slope gradients had higher organic matter and total nitrogen. Soil type affected the four soil nutrients significantly. Soil samples from dry farming land had significantly higher total nitrogen and extractable potassium than soil from paddy fields, while the contrary was found for extractable phosphorus. Along the Yinma River, soil samples from the western part have statistically higher values for organic matter, total nitrogen and extractable potassium than those collected from the eastern part.

microRNA (miR)-142-3p is implicated in malignancy and has been identified as a biomarker for aggressive and recurrent lung adenocarcinomas. This study aimed to evaluate the inhibitory effect of miR-142-3p on apoptosis and inflammation induced by bleomycin in MLE-12 cells. MLE-12 cells were first transfected either with miR-142-3p mimic or miR-142-3p inhibitor and then the cells were exposed to 50 μg/mL of bleomycin. Thereafter, cell viability, apoptosis and the expression of pro-inflammatory cytokines were assessed using CCK-8, flow cytometry, RT-PCR and western blot analyses. Cox-2, PI3K, AKT and mTOR expressions were detected by western blotting after bleomycin was administered together with NS-398 (an inhibitor of Cox-2). As a result, cell viability was significantly decreased, as well as apoptosis and the expression of IL-1 and TNF-α were remarkably increased after 50 and 100 μg/mL of bleomycin administration. miR-142-3p overexpression alleviated bleomycin-induced apoptosis and overproduction of these two pro-inflammatory cytokines, while miR-142-3p suppression exhibited completely opposite results. Up-regulation of Cox-2 and inactivation of PI3K/AKT/mTOR were found in bleomycin-pretreated cells, while these abnormal regulations were partially abolished by miR-142-3p overexpression and NS-398. In conclusion, this study demonstrated that miR-142-3p overexpression protected bleomycin-induced injury in lung epithelial MLE-12 cells, possibly via regulating Cox-2 expression and PI3K/AKT/mTOR signaling pathway. These findings provide evidence that miR-142-3p may be a therapeutic strategy for idiopathic pulmonary fibrosis (IPF) treatment.