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• A thermo-mechanical coupled PD model for ECC-concrete bonding specimens. • Within the PD framework, models for ECC and concrete as well as their interface model are constructed. • Considering the degradation of mechanical and thermal properties under high temperature. • The damage of ECC-concrete bonding specimens under fire scenarios are analyzed. • The flow and heat transfer of thermos fluids are modeled using PDDO. The current application of Peridynamics (PD) models in addressing thermally induced failures within Engineered Cementitious Composites (ECC) and concrete bonding specimens is relatively limited. This study introduces a novel semi-discrete PD model for ECC and a random heterogeneous PD model for concrete. These models are grounded in the microscopic constitutive relationships between ECC and concrete materials and incorporate the strain softening behavior of cement-based materials. The effectiveness of the interface model is evaluated through splitting tensile tests on ECC-concrete bonding specimens, employing a series model alongside PD surface effects for material interface correction. Considering the performance degradation of materials at elevated temperatures, a PD thermo-mechanical coupling model, which integrates PD thermal diffusion and motion equations, is proposed to analyze the failure of ECC and concrete under high thermal loads. The validity of both the thermo-mechanical coupling and concrete heterogeneity models is confirmed via thermal cracking tests on heated concrete columns subjected to drilling. Lastly, considering the dynamic response of fire, the Navier-Stokes equation are reformulated into a non-local form utilizing the Peridynamic differential operator (PDDO) to simulate fire environment. A thermo-fluid-mechanical coupling model is developed, and applied to analyze ECC and concrete bonding specimens' failure behaviors under fire scenarios. [ABSTRACT FROM AUTHOR]

Petrochemical wastewater contains a high concentration of refractory aliphatic and aromatic hydrocarbons. Bioremediation of these hazardous materials using autochthonous bioaugmentation (ABA) strategy is attracting increasing interest. Herein, an indigenous biosurfactant-producing bacteria Z11 was isolated and identified as Enterobacte r sp. The reintroduction of Z11 into petrochemical wastewater led to a substantial reduction (P < 0.01) in TPHs, decreasing from 8099 to 1723 mg/L, as well as a significant decrease in COD, decreasing from 8064.2 to 1689.2 mg/L. At a critical micelle concentration of 200 mg/L, the biosurfactant synthesized by Z11 exhibited an extraordinary decrease in surface tension from 67.5 to 29 mN/m. The biosurfactant demonstrated favorable surface activity over a wide pH, temperature, and salinity range. Based on a series of chemical analyses, the biosurfactant was classified as phospholipid. The autochthonous bioaugmentation technique developed by Z11 indicated a significant increase (P < 0.05) in the degradation of n-alkanes of varying chain lengths and polycyclic aromatic hydrocarbons. The analysis of the microbial composition demonstrated that the addition of Z11 caused a rise in bacterial populations capable of hydrocarbon decomposition, such as Pseudomonas sp. and Stenotrophomonas sp. The activities of two enzymes involved in degradation, alkane hydroxylase and alcohol dehydrogenase, increased dramatically and showed a significant (P < 0.05) correlation with Enterobacter sp. Z11. The proposed mechanism could be elucidated that functional genes regulate the secretion of biodegradation enzymes and biosurfactants to promote the deep degradation of petroleum hydrocarbons. This study provides technical support for the reintroduction of autochthonous microorganisms capable of producing biosurfactants in implementing in situ ABA strategies. [Display omitted] • The biosurfactant produced by Z11 exhibited superior stability and surface activity. • The inoculation of strain Z11 triggered and accelerated oil degradation process. • The addition of Z11 increased the hydrocarbon-degrading bacterial populations. • The reintroduction of Z11 enhanced the activity of bacteria and enzymes. • The proposed mechanism of autochthonous bioaugmentation strategy was elucidated. [ABSTRACT FROM AUTHOR]

An efficient ultrasonic disruption extraction (UDE) of polysaccharides from Armillaria mellea (AM) were optimized by response surface methodology (RSM). Under optimum conditions: ultrasonic power 915.00 W, temperature 69.27 °C and time 39.13 min, the crude polysaccharides (AMPs) yield was 19.5%. Two purified fractions AMPs-1-1 and AMPs-2-1 were obtained through anion-exchange and gel chromatography. AMPs-1-1 was a heteropolysaccharide with average molecular weights of 1.23 × 105 Da, and composed of Glc, Gal and GlcA with mole percentages of 89.06%, 9.59% and 1.34%, respectively, owning a backbone structure of (1→)- β - d -Glc p , (1 → 3,6)- α - d -Glc p and (1 → 3)- β - d -Glc p residues. AMPs-2-1 was a heteropolysaccharide with average molecular weights of 6.76 × 104 Da, and composed of Glc, Gal, GlcA and Man with mole percentages of 65.28%, 22.87%, 2.87% and 8.98%, containing a main backbone chain of (1 → 3,6)- α - d -Glc p and (1 → 6)- β - d -Glc p residues. AMPs-2-1 possessed obviously antioxidant activities in terms of stronger scavenging activity against DPPH· and ABTS+⋅, higher FRAP and ORAC value than AMPs-1-1. AMPs-2-1 could promote splenocyte lymphocytes and RAW264.7 macrophages proliferation and enhanced the phagocytosis of macrophages, exhibited significant immunomodulatory activities. These results suggested that UDE is an effective extract technology, and AMPs-2-1 could be explored as potential natural antioxidants and immunomodulatory agents. • An effective ultrasonic disruption extraction process was optimized by response surface method. • Two homogeneous polysaccharide components had been isolated from wild Armillaria mellea. • Characteristic of polysaccharide was characterized by HPGPC, HPLC, GC–MS, IR, NMR. • AMPs-2-1 showed notable antioxidant and immunomodulatory activities. [ABSTRACT FROM AUTHOR]

Highlights • The numerical simulations for thermal contact resistance are based on practical surface topography of 3D C/C-SiC needled composites. • Temperature distributions between the contact interface have been studied, and the proportion of the actual contact area has been calculated. • Thermal contact resistance are in the order of 6 × 10−4–1.2 × 10−3 K·m2·W−1 in this paper. Abstract The 3D C/C-SiC composite is a kind of widely used material in thermal protection system or other functional parts of the hypersonic vehicles. This paper conducts numerical simulation to predict the thermal contact resistance of the 3D C/C-SiC needled composite pairs. The practical surface topography is measured by a 3D optical microscope named Bruker Contour GT-K, and the rough surfaces for simulation are reconstructed in ANSA software with the help of Python code. The measured arithmetical mean roughness (Ra) of the two specimens are 12.04 μm and 11.75 μm respectively. The prediction is divided into two steps, static analysis for revealing the contact spot distribution of the contact interfaces, and thermal analysis for the temperature distribution of the contact interfaces to calculate the thermal contact resistance. Both two steps are finished with Abaqus. The prediction results show that actual contact area only occupies a small part of nominal contact area (when pressure is 5.52 MPa, the actual contact area just accounts for 7% of the nominal contact area), and the dependency curve approximately shows linearity between the proportion of actual contact area to nominal contact area and loading pressure. Besides, thermal contact resistance decreases with an increase in loading pressure and temperature. Thermal contact resistances of the studied composite materials are in the order of 6 × 10−4–1.2 × 10−3 K·m2·W−1. [ABSTRACT FROM AUTHOR]

Highlights • A novel index (N efficiency index, NEI) successfully predicted photosythetic nitrogen use efficiency (PNUE). • The novel index can be presented as 1.8 + R 680 R 850 × R 760 + R 680 R 850 + R 680 , and it reduced soil and leaf cluster effects. • NEI enable different stage datasets (vegetative and reproductive stages) to be modelled uniformly. • NEI exhibited a superior predictive capacity for PNUE when compared with the common indices. • NEI accurately estimated PNUE of wheat across experimental conditions using remote sensing. Abstract Non-destructive and rapid methods for estimating nitrogen efficiency are helpful in quantifying and communicating the N use efficiency (NUE) in agricultural production. To accurately evaluate NUE, we analysed the quantitative relationship between leaf photosynthetic nitrogen use efficiency (PNUE) and wheat NUE, and investigated the quantitative relationship between PNUE and hyperspectral indices in winter wheat. Our field experiments were carried out during 2013–2016 across different growth stages, cultivars, planting densities, nitrogen (N) rates, and water treatments, and a nitrogen efficiency index (NEI) was developed to evaluate PNUE. Three of eight previously developed vegetation indices (VIs) performed well when regressed against PNUE; however, they exhibited bias between vegetative and reproductive stages. The NEI was obtained by integrating the reflectance at the red band (680 nm) into simple ratio index (SR (760,850)), to become a modified simple ratio index (mSR (760,850,680)), then we added a floating coefficient [1.8 + (R 680 /R 850)] to mSR (760,850,680). Our novel index was better related with PNUE than previous VIs under different experimental conditions. There was no significant difference in the slope and intercept under the five experimental factors, suggesting that the new index is a superior tracker for PNUE changes under heterogeneous field conditions. These models accurately estimated PNUE in winter wheat, providing a theoretical basis and technical support for N fertilizer assessment and screening of N efficient wheat varieties. [ABSTRACT FROM AUTHOR]

Optimization design of thermal protection system of aerospace vehicles with progressively increasing flying speeds needs a deepened study on the thermal conduction characteristics of corresponding materials. As a potential thermal protection material, C/C-SiC 8-harness (8HS) satin woven composites with piercing fiber bundles are numerically studied in this work. The numerical model is established based on the investigation of 8HS satin weave textile. A full and a half unit cell models are formulated according to three non-orthogonal translational and one further 180° rotational symmetries, respectively. The two unit cells have much smaller sizes and also less computational costs than the rectangle unit cell available in previous literatures. The thermal boundary conditions are derived rigorously and are verified by the identical numerical results obtained by the two unit cells. The developed unit cell method and the related boundary conditions derivation process can be references for other multi-harness satin woven composites. The numerical model is validated by the experimental result obtained in this work and that available in the literature. The influences of constituents (carbon fiber, matrix C, matrix SiC and porosities) volume fractions, piercing fiber bundles and thermal contact resistance between matrix and fiber bundles on the effective thermal conductivities are studied. [ABSTRACT FROM AUTHOR]

Long-term low cyclic loads are often encountered in marine environment, but the cyclic behavior of soil under this loading condition is rarely studied. Undrained pore pressure behavior of soft marine clay subjected to long-term low cyclic loading is of considerable importance for the proper design and maintenance planning of foundations of near- and off-shore structures. In this paper, a new hyperbolic model is proposed to predict the development of undrained pore pressure. This model is verified by experimental data from literature. Compared with the existing models, the proposed model has better capability and performance. With use of the proposed model, a hyperbolic relationship between cumulative plastic strain and pore pressure was derived and verified by experimental data. Finally, the effects of cyclic stress ratio, confining pressure and loading frequency on pore pressure are investigated. In summary, this work provides a novel model and some innovative observations to better understanding undrained pore pressure behavior of soft marine clay under long-term low cyclic loads. [ABSTRACT FROM AUTHOR]

Long-term cyclic loads with a stress level lower than the critical cyclic stress applied on soft soil can lead to soil deformation but not to failure. The Monismith model is known for its simplicity and capacity to describe the cumulative plastic strain of soil under cyclic loads. However, it is unsuccessfully applied in these cases because the plastic strain in this model would increase endlessly till to failure with increasing number of load cycles. To solve this problem, a novel empirical model with three parameters is proposed based on analogy analysis of the Hardin-Drnevich model and Monismith model. The proposed model is verified by experimental data from existing literature and is shown to have better capability and performance than the Monismith model in predicting the cumulative plastic strain of soft soil subjected to long-term low cyclic loads. The value of parameter b is recommended to be 0.5, and relationships of parameters a and c with the cyclic stress ratio are also proposed for soft clay. Applications of the proposed model are elaborated in detail, and in situ test results for settlement of soft subgrade are used to evaluate the performance of this model. The prediction results are consistent with the test results. The research results present a promising method for investigating the development of deformation and the settlement of soft foundation in the near-shore and off-shore areas caused by wave and/or traffic loads. [ABSTRACT FROM AUTHOR]

Soft clay is fragile to be disturbed and to produce deformation under cyclic loads. A simple theoretical energy method is presented to explore the dynamic response of soft clay under cyclic loads, then to discuss its deformation behavior. In the formulation, equations are derived based on general thermodynamic principle and Newton's laws of motion. A series of cyclic triaxial tests are conducted for undisturbed samples of soft clay to verify the proposed method. Cumulative deformation is computed by the proposed approach. Results are compared with the experimental data, and good agreement is achieved. This paper develops a new insight to describe deformation behavior of soft soil under cyclic loads, and to predict the plastic accumulative deformation. [ABSTRACT FROM AUTHOR]

Realizing accurate measurement for thermal contact conductance (TCC) is difficult and needs many additional measurements. In this paper, we design a three-layer back propagation artificial neural network (ANN) model to retrieve TCC of two contact solid specimens. The model can retrieve TCC only according to the measured temperatures and loading pressures, and the effects of loading pressure, temperature and surface roughness on TCC are considered. Besides, thermal conductivity, heat flux and the parameter of the TCC empirical fitting formula can be obtained simultaneously. The retrieved results are validated by experimental values. The results show that for two contact pairs with different surface roughness, the retrieved parameters of TCC empirical fitting formula are clear reasonable and can be explained conceptually compared with the published studies. [ABSTRACT FROM AUTHOR]

White spot syndrome virus (WSSV) is one of the most dangerous pathogen in shrimp aquaculture, which can cause extremely high mortality of shrimp. A full understanding of virus-host interactions is important to prevent viral infection. In the present study, wsv089-interacting molecule Litopenaeus vannamei peroxiredoxins2-like (LvPrx2-L) was selected by the yeast two-hybrid (Y2H) method. The interaction between wsv089 and LvPrx2-L was confirmed by far-western blotting assay. Interestingly, a further study indicated that LvPrx2-L interacted with VP26, and the molecular docking analysis supported the interaction between LvPrx2-L and VP26. Tissues distribution assay showed that LvPrx2-L was detected in all sampled tissues. The highest expression of LvPrx2-L was appeared in hemocytes. Following WSSV challenge, LvPrx2-L mRNA transcripts were significantly increased in the hemocytes and gill. In addition, the relative expression of IE1 and VP28 were remarkably up-regulated in the hepatopancreas and intestines of LvPrx2-L -knockdown shrimp. Moreover, the cumulative survival rate was significantly lower in the LvPrx2-L- silenced group compared with the control and blank groups. Furthermore, LvPrx2-L could regulate the expression of proPO, crustin, ALF3, and CAT at the mRNA level. These findings would further deepen our understanding of WSSV-host interaction and shrimp antiviral response. All these data might useful for assessing the function of LvPrx2-L in the immune response of crustacean. • wsv089 and VP26 interacts with LvPrx2-L. • LvPrx2-L mRNA transcripts were significantly increased after WSSV challenge. • IE1 and VP28 were remarkably up-regulated in LvPrx2-L knockdown shrimp. • The cumulative survival rate was significantly lower in LvPrx2-L silenced group. • LvPrx2-L regulate the mRNA expression of proPO , crustin , ALF3 and CAT. [ABSTRACT FROM AUTHOR]

• Proposed a dual-iterative thermal-mechanical coupling method (DICM). • Thermal expansion effect on TCR prediction is analyzed. • DICM is recommended for simulation contact pairs with axisymmetric geometry. This study investigates the effect of thermal expansion on thermal contact resistance prediction, proposing a dual-iterative coupling method (DICM). The contact surfaces in the simulation model are reconstructed based on either the actual measured topography or the hypothetical topography, and a mathematical formulation for numerically predicting the thermal contact resistance (TCR) is established. The DICM includes four steps: first, mechanical analysis is conducted based on the ideal single point contact condition, according to the elastic–plastic constitutive equations. Second, heat transfer analysis is carried out based on the deformed geometry originating from the prior mechanical analysis. Third, another step of mechanical analysis is implemented to consider the effect of thermal expansion with the temperature distribution determined in the second step. Fourth, another step of heat transfer analysis is carried out based on the deformed geometry originating from the second-step mechanical analysis. The conventional prediction method only contains the first and second steps, and is known as the single sequential coupling method (SSCM). The TCRs of two engineering examples are predicted using both DICM and SSIM. The results show that the mechanical–thermal-mechanical–thermal dual-iterative coupling method, i.e., DICM, should be recommended for simulating contact pairs with axisymmetric geometries, while SSCM is suggested for contact pairs with non-axisymmetric geometry. [ABSTRACT FROM AUTHOR]

In this paper, thermal contact resistance (TCR) of three different contacts of a composite are experimentally investigated when the contact interfaces are filled with air. The surface roughnesses of the three contacts are 0.95/16.91 μm (Contact A, titanium alloy/composite), 9.54/9.73 μm (Contact B, composite/composite), and 11.53/6.85 μm (Contact C, composite/titanium alloy). The measured TCRs of the three contacts decrease with an increase in loading pressure and interface temperature. For Contact B, the effect of temperature on thermal contact resistance gradually decreases with an increasing loading pressure. For Contact C when loading pressure increases to 3.6 MPa, the decreasing trend of the thermal contact resistance with increasing loading pressure becomes mild. Additionally, experimental uncertainties are analyzed and calculated. [ABSTRACT FROM AUTHOR]

• The first attempt to explore why strong employment support for PwDs has not brought about positive outcomes in China. • Under the productivist ideology, PwDs are regarded as inefficient and a drag on economic development. • Government support for PwDs is all talk, no action; quasi-governmental support just goes through the motions; and the primary group is self-centered. • Primary group is hypocritical and unsustainable as it's complicated by the issues of face and repaying favors. Employment is an important way for persons with disabilities (PwDs) to participate in society and fulfil their potential. However, despite the impression that employment support for PwDs is improving, why is the actual employment situation in China stagnant or even worsening? In order to answer this question, this paper uses a qualitative study in BTQ City, QL Province, China to analyze the causes of the general problems in employment support for PwDs by breaking them down into official government, quasi-government, and primary support groups. This study finds that the prioritization of 'economic development' dominates people's thinking and actions, to the detriment of social and economic goals. Consequently, the responses of the three employment support systems are: (a) an official government focus on "productivism" means PwDs employment is not a priority, and official support is usually "all talk, no action"; (b) bureaucratic quasi-government organizations are reluctant to assist beyond mere formalities to boost PwDs employment as this does not form part of their performance assessment; and (c) individualism resulting from societal breakdown makes the primary support group perceive a lack of benefit in assisting PwDs, and any assistance they render is done purely out of self-interest and are therefore unsustainable. We hope that the findings of this study will provide some inspiration and reference for improving the employment policy of PwDs in China. [ABSTRACT FROM AUTHOR]

In this paper, thermal contact resistance between a pair of 8-harness satin woven pierced composites is numerically investigated when the interface gaps are filled with air. Numerical model of the rough surfaces is based on measured results of actual specimens by a microscope. The results show that thermal contact resistance decreases with an increase in both loading pressure and temperature. The effects of interfacial thermal radiation on the predicted thermal contact resistance increase with an increase in temperature, but less than 5%. The percentage of heat transfer rate through solid contact regions occupies less than 17% of overall heat transfer rate for the cases studied with solid thermal conductivity around 10 W·m−1·K−1 and loading pressure up to 2.37 MPa. For the studied composite pair (averaged surface roughness of 12.30 μm, 10.54 μm) thermal contact resistance is in a range of 9.8 × 10−4 - 5.7 × 10−4 K·m2·W−1. • The numerical simulations are based on practical surface topography. • The actual contact distribution and temperature distribution have been studied. • The effect of interfacial thermal radiation is investigated. • The portion of heat transfer rate through actual contact area is calculated. [ABSTRACT FROM AUTHOR]

Highlights • Proposed a thermal contact resistance prediction model. • Radiation effect whether to be considered is analyzed. • The prediction model is experimentally validated. Abstract The precise prediction or test of thermal contact resistance is a key issue on increasing or decreasing thermal energy transmission efficiency between two solids. This paper raises a thermal contact resistance prediction model based on measuring actual surface topography under different loading pressures and different heating temperatures. The actual topography of contact surfaces is measured by a 3-D optical microscope named Bruker Contour GT-K. The contact surfaces are reconstructed with language Python according to the data of surface topography from the microscope and the numerical contact model is generated. Then the thermal contact resistance simulation is implemented with software ABAQUS. Based on the elastic-plastic constitutive equations and steady state heat conduction theory, finite element analysis of mechanical and heat transfer performance of the contact model is performed with ABAQUS in the light of sequential coupling method. The studied material pairs are Ti-6Al-4V—Ti-6Al-4V with three kinds of different interstitial material e.g., vacuum, air and conductive silicone grease. The effect of radiation on thermal contact resistance under air and vacuum atmosphere is further studied and analyzed. Besides, the solid thermal conductivity on thermal contact resistance is investigated. To verify the accuracy of the method, the simulated results from ABAQUS are compared with the experimental results of air gap with the same boundary conditions. The maximum deviation between simulation results and experimental results is 9.57% while 75% of the deviations are within 5%. A correlation of thermal contact conductance with the average contact surface temperature and loading pressure is proposed. The results show that this method has high precision to predict thermal contact resistance in the engineering application. [ABSTRACT FROM AUTHOR]

This paper addresses the vibration control problems of uncertain systems with both random and multidimensional parallelepiped (MP) convex variables by uniting the optimal saturation nonlinear control (OSNC) and an active learning Kriging (ALK) method. This method can be named ALK-MP-OSNC. The dynamic equations of the controlled systems can be written in ODE forms, and the functions containing saturation nonlinearities on the right side of each of ODE equation can be approximately replaced via using the Kriging model. The efficiency of the Kriging model can be improved through combining the differential evolution (DE) global optimal algorithm with the distance constraint condition. A three-pendulum system, a satellite motion and a moving-mass beam system are employed to demonstrate the performance of the improved ALK-MP-OSNC. Results indicates that the proposed method can efficiently drive the uncertain pendulum system to a chaotic behavior and the other two uncertain systems to a periodic motion. The efficiency and the accuracy of the proposed method can be researched through comparing with the original ALK and the Monte Carlo simulation. In conclusion, the proposed method can be applied to complex engineering fields such as aerospace engineering, civil engineering, ocean engineering, and space deployable engineering. • An improved Kriging model is proposed by combining differential evolution algorithm with distance constraint conditions. • A distance constraint condition for improving the sample points is developed. • Mixed uncertain optimal saturated nonlinear control with the improved Kriging method is proposed. [ABSTRACT FROM AUTHOR]

Nonlinearities, uncertainties and unknown external loads decline tracking dynamic performance and steady-state accuracy of electro-hydraulic systems. Most existing electro-hydraulic controllers have well guaranteed both the cylinder position and the load pressure asymptotic stable or uniformly ultimately bounded. However, the corresponding output response is relatively slow and achieves the desired performance in an infinite time, which cannot meet the requirements of fast convergence in some engineering applications. In this study, a fixed-time adaptive neural control (FTANC) is proposed for an electro-hydraulic system to improve the fast convergence performance and steady-state accuracy of the cylinder position in case of hydraulic model uncertainties A rigorous theoretical derivation proves that the electro-hydraulic system obtains practically fixed-time stability, such that all system state errors converge to the zero neighborhood in a fixed time without relation to the initial conditions of electro-hydraulic systems. Finally, both the simulation and experimental results verify the effectiveness of the proposed control method. [ABSTRACT FROM AUTHOR]

• An ECC-concrete composite beam with a fully-discrete model, taking into account the cementitious matrix and concrete softening characteristics, has been established. • An energy-based interface model using the peridynamic method has been established. • The effects of factors such as fiber volume fraction, ratio of ECC layer thickness, impact velocity, and fiber length on the performance of an ECC-concrete composite beam considering the strain rate effect under impact loading have been analyzed. Engineering cement-based composite materials (ECC) are widely used for strengthening concrete structures and resisting impact loads. However, the impact failure process of materials involves the material discontinuity. To address this issue, this paper constructs a fully discrete model of ECC concrete composite beams under impact loads based on peridynamics (PD). In this model, the cement matrix is described using an exponential model, while the fibers are modeled using PD rods. The interaction between the fibers and the matrix is described based on the classical exponential friction attenuation model, while considering failure criteria based on strain rate effects. Finally, by employing the established model, the effects of impact velocity, fiber volume fraction, ECC layer thickness ratio, and fiber length on the impact performance of ECC concrete composite beams were investigated. Results showed that impact velocity affects the damage evolution and crack propagation mode of the composite beams by affecting the dynamic critical elongation of PD bonds. The fiber volume fraction, ECC layer thickness ratio, and fiber length all have important effects on the ductility and energy absorption capacity of composite beams. [ABSTRACT FROM AUTHOR]

The mitochondria have been identified as key targets in nonalcoholic fatty liver disease (NAFLD), one of the most prevalent chronic liver damage diseases globally. Meanwhile, the biological information analysis in this study revealed that SIRT1, PPARG, PPARA, and PPARGC1A (mitochondrial biogenesis-related proteins) were NAFLD therapeutic targets. Therefore, the design and synthesis of targeted drugs that promote mitochondrial biogenesis and improve mitochondrial function are particularly important for NAFLD treatment. Recently, we introduced butyls, hydroxyls, and halogens to benzophenone and synthesized a series of NAFLD-related 4-butylpolyhydroxybenzophenone compounds, aiming at investigating the hepatoprotective activity from the aspect of mitochondrial biogenesis. The structure-activity relationship demonstrated that hydroxyl and ketone groups were active groups interacting with mitochondrial biogenesis proteins (SIRT1 and PGC1α), and the activity was stronger when the o-hydroxyl group was present on the benzene ring. In contrast, the activity was little affected by the presence of the p-hydroxyl group, m-hydroxyl group, butyl group type, or halogen. In addition, in vitro studies confirmed that these compounds could directly bind to SIRT1 and PGC1α, markedly promote their interaction, significantly increase the expression of proteins and genes related to mitochondrial biogenesis (SIRT1, PGC1α, NRF1, TFAM, COX1, and ND6) and subsequently ameliorate mitochondria dysfunction, which was evidenced by the decreased ROS, upregulated ATP production, increased MMP, and enhanced mitochondrial number. According to the outcomes of our in vitro and in vivo experiments, 4-butyl-polyhydroxybenzophenone compounds could also effectively reduce the formation of lipid droplets and liver injury index (ALT, AST, LDH, AKP, γ-GT, and GDH) and improve the level of antioxidant enzymes (GSH and SOD). Particularly, the treatment of these compounds after a high-fat diet could significantly reduce body weight, decrease liver coefficient, attenuate liver damage, and ameliorate lipid accumulation in rat liver, demonstrating their therapeutic effects on NAFLD. Mechanistically, 4-butyl-polyhydroxybenzophenone compounds promoted mitochondrial biogenesis and eventually prevented NAFLD liver injury by activating the PGC1α signaling pathway in a SIRT1-dependent manner, which was strongly supported by SIRT1 inhibitor EX527. [Display omitted] • • (1)The targets of NAFLD (SIRT1, PPARG, PPARA, and PPARGC1A (mitochondrial biogenesis-related proteins)) were identified by bioinformatics analysis. • By introducing butyls, hydroxyls, and halogens to benzophenone and a series of NAFLD-related 4-butylpolyhydroxybenzophenone compounds were synthesized and confirmed by ESI-MS, 1H NMR, and 13C NMR. In addition, their structure-activity relationships were summarized. • The mechanism of these compounds (PGC1α signaling pathway via a SIRT1-dependent manner) was investigated from the perspective of disease targets and mitochondrial biogenesis. [ABSTRACT FROM AUTHOR]

The stress response of omnivorous gibel carp ( Carassius auratus gibelio ) and carnivorous largemouth bass ( Micropterus salmoides ) with different nutritional history were evaluated. A 2 × 2 layout, including two fish species (gibel carp or largemouth bass) and two nutritional history (fasted or fed to satiation for four weeks), was used. After feeding or fasting, the fishes were subjected to an acute handling. Fasting resulted in decrease of plasma glucose level and liver glycogen content of gibel carp and largemouth bass. After handling stress, plasma levels of cortisol, glucose and lactate of gibel carp and largemouth bass increased, regardless the fasted fish or fed fish. During the period from 0 h to 24 h post-stress, the fasted gibel carp exhibited lower plasma cortisol and glucose levels, brain and liver glycogen contents, and liver phosphoenolpyruvate carboxykinase (PEPCK) activity compared with the fed counterpart. The plasma glucose level, brain glucose level, brain and liver glycogen contents were lower, while the liver PEPCK and hexokinase (HK) activities were higher, in the faster largemouth bass than the fed counterpart. This study indicates that nutritional history can influence stress response of gibel carp and largemouth bass, and the stress response is less severe in the fasted fish relative to the fed counterpart. This study also reveals that gibel carp and largemouth bass may have different strategies in response to fasting and acute handling stress. [ABSTRACT FROM AUTHOR]

This paper investigated the microstructure and tribological behavior of Ni60 alloy coating prepared on the surface of aluminum alloy (ZL109) by plasma spray. The ANSYS software was applied to compare the deformation and temperature of nickel-based alloy coating deposited on aluminum alloy piston with the thickness of 300 µm, 400 µm and 500 µm. X-ry diffraction (XRD) and Scanning Electron Microscopy (SEM) with Energy Dispersive X-ray Spectroscopy (EDS) were used to characterize the phase, microstructure and chemical composition of Ni60 alloy coating. Besides, fractal theory was used to study the geometric morphology of materials. The tribological properties of the coating were investigated under oil-lubrication at 100 °C through the circular cyclic test with Si 3 N 4. The result shows that the piston skirt deformation was the smallest when the coating thickness was 300 µm. Multiple phases such as chromium carbide and Ni 3 Fe phases were contained in the coating, and Si element was dispersed in the Ni60 alloy powders with the form of silicon oxide, which enhanced the hardness and oxidation resistance of the coating. The porosity of the coatings prepared under three power conditions (P = 40 kW, P = 50 kW and P = 45 kW) were 1.58%, 1.47% and 0.97%, respectively. When the load increased from 80 N to 100 N, the depth and width of the wear scar increased and the wear volume added from 1.54 × 108 μm3 to 3.45 × 108 μm3. The friction coefficient of the coating increased with the increment of load. By comparison, the coating with moderate spraying power has less weight loss and better wear resistance under higher wear load. • The coating thickness was determined through thermo-mechanical coupling analysis. • The microstructure and tribological behavior of Ni60 alloy coating were studied. • The expansion degree of piston after spraying is lower than before spraying. • The coating has better wear resistance when the spraying power is moderate(P = 45 kW). [ABSTRACT FROM AUTHOR]

Abstract: Two strains each of Propionibacterium freudenreichii ssp. shermanii and P. freudenreichii ssp. freudenreichii were tested for their ability to produce conjugated linoleic acid (CLA) in sodium lactate medium (SLM), De Man-Rogosa-Sharpe (MRS) medium and skim-milk. Data showed that both strains were able to produce CLA in three media supplemented with different concentrations of sunflower oil. Maximum production of CLA (78.8μg/ml) was observed after 36h of incubation in MRS containing 12mg/ml of sunflower oil by P. freudenreichii ssp. shermanii. Moreover, the growths of both strains were inhibited by sunflower oil and a positive relationship between CLA production and ability to tolerate sunflower oil was observed. At the same time, it was also observed that the inhibitory effects on P. freudenreichii ssp. shermanii and P. freudenreichii ssp. freudenreichii in three media follow the order SLM>skim-milk>MRS and SLM>MRS > skim-milk, respectively. Micro aerobic conditions were in favour of increasing the amounts of CLA. The amounts of CLA increased from 0 to 36h under micro aerobic conditions and no significant (p >0.05) increases in total CLA levels were observed after 80h of incubation. Results showed that P. freudenreichii may have potential for producing CLA. [Copyright &y& Elsevier]