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This study aimed to investigate the effects of phosphorus (P) restriction and fenofibrate (F) on lipid deposition, mitochondrial function and protein synthesis in obscure puffer using in vivo and in vitro studies. In vivo, healthy fish with an initial body weight of 18.21 ± 0.04 g were fed three diets supplemented with different P and fenofibrate contents for 10 weeks: Control (5.3 g/kg P), P0 (0 g/kg P) and P0 + F (0 g/kg P and 3.5 g/kg F). The results indicated that P0 treatment significantly reduced weight gain rate and protein deposition, but increased body lipid accumulation, hepatic lipid droplets and serum triglyceride and cholesterol content (P < 0.05). However, P0 + F treatment reversed these. Furthermore, P0 treatment was found to inhibit the mRNA levels of pparα, lpland cyp7a1, whereas P0 + F treatment significantly increased the expression levels of these genes. In vitro, primary hepatocytes were cultured for 48 h in three different culture media: Control (normal DMEM medium), P0 (DMEM without P), and P0 + F (DMEM without P + 200 mM F). The results showed that P0 significantly decreased the mRNA and protein expression levels of Pparα (P < 0.05), and P0 + F up-regulated mRNA expression levels of pparα compared with P0 group (P < 0.05). Furthermore, P0 inhibited the expression levels of genes associated with fatty acid β-oxidation (cpt1and acox1) and transport (cd36), but elevated the expression levels of genes related to lipid synthesis (fas, me, g6pdand dgat1) and cholesterol synthesis (hmgcr)(P < 0.05). However, P0 + F reversed these effects. P0 decreased mitochondrial abundance, membrane potential and ATP content, increased the mRNA expression level of ampkand 4epb1and inhibited the mRNA expression of pgc1-αand the protein expression of mTOR and S6k (P < 0.05), whereas P0 + F increased mitochondrial abundance and membrane potential, increased mtormRNA expression and inhibited 4ebp1mRNA expression. Overall, this study suggests that P deficiency leads to lipid and cholesterol accumulation and impaired growth in fish, and fenofibrate can alleviate these effects by improving lipid and cholesterol metabolism, mitochondrial function, and protein synthesis.

The electrical conduction mechanism of the hydrous minerals under high pressure is of great significance for understanding the high conductivity of the mantle and the Earth’s internal water. Therefore, in situ alternate current impedance spectra of the micropowder goethite have been measured under pressures up to 17.1 GPa using a diamond anvil cell. The results indicate a pressure-induced conduction mechanism transition around 5 GPa from a mixed protonic and electronic conduction to pure electronic conduction. By selecting appropriate equivalent circuit models, the electrical parameters of the protons and electrons in the bulks and the grain boundaries under compression have been extracted. The pressure suppresses the protonic diffusion, leading to the increased protonic resistance under compression. The changes in electronic resistance in the two magnetic states of goethite relate closely to the band gap variation under compression. In addition, both the relaxation and the conduction process show that the grain boundary is dominant and the pressure effect is mainly reflected in the grain boundary, which results from the enrichment of the cation defects in the space-charge layers at equilibrium based on the space-charge potential calculation.

The grain size effect is one of the fundamental characteristics of semiconductor gas sensors. However, it has not been fully understood due to the absence of studies on the volume-depleted grains. In this work, the gas-sensitive SnO2quantum dots (QDs) from partial depletion to volume depletion are prepared to discuss the size effects. A facile aqueous-based method is used to prepare the size-controllable SnO2QDs of 2.0–12.6 nm. The resistance shows a monotonically negative size effect while the response reaches the optimization when the grain radius is comparable to the depletion layer width. It is suggested that the design of highly sensitive gas sensors should consider the equal importance of the control of grain size and depletion layer width. The computational results illustrate size-dependent energy level of donors and number of quasi-free electrons, which are responsible for the negative size effect of resistivity in the volume-depleted SnO2crystallites. This work provides a comprehensive understanding of grain size effects from partial depletion to volume depletion in semiconductor gas sensors.

To study the surface forming mechanism of the solid–liquid two-phase abrasive flow processing, the large eddy simulation method was used. Taking a 90° stainless steel elbow as the research object, the action mechanism of the dynamic pressure, wall shear force, flow state of the abrasive flow at different cross-sections, formation of the vortex, and trajectory of the abrasive flow on the inner surface of the elbow with abrasive flow composed of solid-phase silicon carbide and liquid-phase hydraulic oil are discussed. This study explores the distribution characteristics of the flow pattern of solid–liquid two-phase abrasive flow. Moreover, the wear and erosion of the abrasive grain and the wall of the workpiece are discussed. The mechanism of surface formation of solid–liquid two-phase abrasive flow is revealed.

At present, fixing Android system vulnerabilities relies on official Android support and various equipment manufacturers, and it is mainly implemented by system upgrades. This situation causes many problems, such as high costs and delayed fixing of vulnerabilities. This study is performed to design a novel fixing policy construction model targeting Android system vulnerabilities, which can be used for vulnerability feature quantification and fixing policy customization. On this basis, a novel security vulnerability solution called DroidHFix is proposed and implemented. This solution constructs security policies and loads security policy files during the risky application startup. The system helps to fix Android system vulnerabilities dynamically and defend against attacks on the risky application depending on system vulnerability exploitation. Experimental results show that DroidHFix fixes the Android system vulnerabilities effectively, with good performance and compatibility.

The n-3 long chain polyunsaturated fatty acids (n-3 LC-PUFA) play important roles in the normal growth and metabolism of fish . In order to explore the appropriate requiremnts of n-3 LC-PUFA in juvenile largemouth bass Micropterus salmoides, a freshwater carnivorous teleost, four isoproteic (50 %) and isolipidic (11 %) diets were formulated. The control diet used fish oil (FO) as the sole lipid source, and the other three diets used mixed vegetable oil as the main lipid source and supplemented with 0.50 %, 0.80 % and 1.10 % n-3 LC-PUFA, respectively. After the juvenile largemouth bass (initial weight 12.11 ± 0.01 g) fed with the four diets for 75 days, the growth, serum and heptic biochemical indices, as well as hepatic lipid metabolism were investigated. The results showed that the growth performance of 0.50 %-1.10 % groups were high that of control group; comparing to the 1.10 % group, high weight gain, specific growth rate and daily gain, as well as muscle hardness, chewiness and gumminess were detected in the 0.80 % group (P < 0.05). With the increase of dietary n-3 LC-PUFA levels, the serum biochemical indices (total cholesterol, triglyceride, and aspartate aminotransferase activity) and hepatic triglyceride were significantly decreased, while the serum acid phosphatase and alkaline phosphatase, as well as hepatic and muscle n-3 LC-PUFA contents were significantly increased (P < 0.05). Compared with the 0.50 % group, high hepatic mRNA expression levels of anti-inflammatory genes (il-10, tgf-β) were observed in the 0.80 % group (P < 0.05); and the relatively high transcript levels of genes related to lipid transport and catabolism (hsl, pparα, fatpand mtp) and low transcript levels of genes related to lipid anabolism (accαand pparγ) were detected in the 0.80 % and 1.10 % groups, as well as high mRNA levels of accαand pparγwere measured in the 0.80 % group (P < 0.05). The results indicated that 0.80 % dietary n-3 LC-PUFA level is suitable for largemouth bass concerning the growth performance, muscle quality and hepatic lipid metabolism. When subjected the weight gain to the second-order polynomial regression analysis, the maximum value was achieved at 0.76 % n-3 LC-PUFA level, which provide a basis for the development of formula feed for largemouth bass.

The high-pressure electrical transport behavior of microcrystalline tungsten trioxides (WO3) was investigated by direct current electrical resistivity measurement and alternate current impedance spectrum techniques in a diamond anvil cell up to 35.5 GPa. Discontinuous changes of electrical resistivity occurred during the pressure induced structure phase transitions at 1.8, 21.2, and 30.4 GPa. The irreversible resistivity reveals that the structure phase transition is not reversible. In addition, the abnormal changes of bulk resistance and transport activation energy at about 3 and 10 GPa are related to the isostructural phase transition reported by previous Raman study. The temperature induced resistivity change indicates that WO3is a semiconductor from ambient pressure to 25.3 GPa.

We carried out the accurate in situ Hall-effect measurements, the temperature dependence of electrical resistivity measurements and the first-principles calculations in SnO under high pressure. The results of Hall-effect measurements display the carrier transport behavior of SnO under pressure, which indicates that SnO undergoes a carrier-type inversion around 1.3 GPa and an underlying phase transition at 2–3 GPa. In addition, the temperature dependence of electrical resistivity shows that SnO undergoes a semiconductor-to-metal transition around 5 GPa. The calculated band structures based on the first-principles method illustrate that the indirect band gap of SnO vanishes around 4 GPa. In particular, the results of total and partial density of states indicate that the closure of the indirect fundamental gap is mostly attributed to Sn-5s and 5p states hybridized with O-2p states at the Fermi level.

A pressure induced semiconductor-semimetal phase transition on tungsten diselenide has been studied using in situ electrical resistivity measurement and first-principles calculation under high pressure. The experimental results indicate that the phase transition takes place at 38.1 GPa. The first-principles calculations performed by CASTEP code based on the density functional theory illustrate that the indirect band gap of WSe2vanishes at 35 GPa, which results in an isostructural phase transition from semiconductor to semimetal in WSe2. According to the pressure dependence of partial density of states, the semimetallic character of WSe2is mainly caused by W−Se covalent bonding rather than van der Waals bonding.

In view of the current problems that it is difficult to polish small size and complex curved surface, a processing method based on solid-liquid two-phase abrasive flow is proposed. In order to verify the rationality and practicability of the processing method, the numerical simulation is carried out for the processing of solid-liquid two-phase abrasive flow. By using the RNG k-e turbulence model and the Mixture model, the fuel spray nozzle is taken as the research object. The dynamic pressure, the turbulent dissipation rate and turbulent kinetic energy at the nozzle hole are analyzed and compared. The simulation results show that with the increase of inlet velocity, dynamic pressure, fluid velocity and turbulent kinetic energy at nozzle orifice increase at some extent, which tells that the effect of solid-liquid two-phase flow on the pore wall is stronger, the more intense the friction between the fluid and the wall, the better the polishing effect, thus the effectiveness of the abrasive flow processing was concluded and providing theoretical support for the fluid processing of complex components.