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Laser polishing is an emerging efficient technique to remove surface asperity without polluting the environment. However, the insufficient understanding of the mechanism of laser polishing has limited its practical application in industry. In this study, a dual-beam laser polishing experiment was carried out to reduce the roughness of a primary Ti6Al4V sample, and the polishing mechanism was well studied using simulation analysis. The results showed that the surface roughness of the sample was efficiently reduced from an initial 10.96 μm to 1.421 μm using dual-beam laser processing. The simulation analysis regarding the evolution of material surface morphology and the flow behavior of the molten pool during laser the polishing process revealed that the capillary force attributed to surface tension was the main driving force for flattening the large curvature surface of the molten pool at the initial stage, whereas the thermocapillary force influenced from temperature gradient played the key role of eliminating the secondary roughness at the edge of the molten pool during the continuous wave laser polishing process. However, the effect of thermocapillary force can be ignored during the second processing stage in dual-beam laser polishing. The simulation result is well in agreement with the experimental result, indicating the accuracy of the mechanism for the dual-beam laser polishing process. In summary, this work reveals the effect of capillary force and thermocapillary force on molten pool flows during the dual-beam laser polishing processes. Moreover, it is also proved that the dual-beam laser polishing process can further reduce the surface roughness of a sample and obtain a smoother surface.

Flower-like cobalt–molybdenum mixed-oxide microspheres (CoMo-FMs) with hierarchical architecture were successfully synthesized via a hydrothermal process and subsequent calcination step. The characterization results show that CoMo-FMs were assembled from ultrathin mesoporous nanosheets with thicknesses of around 4.0 nm, providing the composite with a large pore volume and a massive surface area. The synthesized CoMo-FMs were employed as catalysts for the aerobic oxidative desulfurization (AODS) of fuel, and the reaction results show that the optimal catalyst (CoMo-FM-2) demonstrated an outstanding catalytic performance. Over CoMo-FM-2, various thiophenic sulfides could be effective removed at 80–110 °C under an atmospheric pressure, and a complete conversion of sulfides could be achieved in at least six consecutive cycles without a detectable change in chemical compositions. Further, the catalytic mechanism was explored by conducting systemic radical trapping and transformation experiments, and the excellent catalytic performance for CoMo-FMs should be mainly due to the synergistic effect of Mo and Co elements.

Opisthorchiosis is a parasitic liver disease found in mammals that is widespread throughout the world and causes systemic inflammation. Praziquantel remains the drug of choice for the treatment of opisthorchiosis, despite its many adverse effects. An anthelmintic effect is attributed to the main curcuminoid of Curcuma longa L. roots—curcumin (Cur)—along with many other therapeutic properties. To overcome the poor solubility of curcumin in water, a micellar complex of curcumin with the disodium salt of glycyrrhizic acid (Cur:Na2GA, molar ratio 1:1) was prepared via solid-phase mechanical processing. In vitro experiments revealed a noticeable immobilizing effect of curcumin and of Cur:Na2GA on mature and juvenile Opisthorchis felineus individuals. In vivo experiments showed that curcumin (50 mg/kg) had an anthelmintic effect after 30 days of administration to O. felineus-infected hamsters, but the effect was weaker than that of a single administration of praziquantel (400 mg/kg). Cur:Na2GA (50 mg/kg, 30 days), which contains less free curcumin, did not exert this action. The complex, just as free curcumin or better, activated the expression of bile acid synthesis genes (Cyp7A1, Fxr, and Rxra), which was suppressed by O. felineus infection and by praziquantel. Curcumin reduced the rate of inflammatory infiltration, whereas Cur:Na2GA reduced periductal fibrosis. Immunohistochemically, a decrease in liver inflammation markers was found, which is determined by calculating the numbers of tumor-necrosis-factor-positive cells during the curcumin treatment and of kynurenine-3-monooxygenase-positive cells during the Cur:Na2GA treatment. A biochemical blood test revealed a normalizing effect of Cur:Na2GA (comparable to that of curcumin) on lipid metabolism. We believe that the further development and investigation of therapeutics based on curcuminoids in relation Opisthorchis felineus and other trematode infections will be useful for clinical practice and veterinary medicine.

Satellite remote sensing images contain adequate ground object information, making them distinguishable from natural images. Due to the constraint hardware capability of the satellite remote sensing imaging system, coupled with the surrounding complex electromagnetic noise, harsh natural environment, and other factors, the quality of the acquired image may not be ideal for follow-up research to make suitable judgment. In order to obtain clearer images, we propose a dual-path adversarial generation network model algorithm that particularly improves the accuracy of the satellite remote sensing image super-resolution. This network involves a dual-path convolution operation in a generator structure, a feature mapping attention mechanism that first extracts important feature information from a low-resolution image, and an enhanced deep convolutional network to extract the deep feature information of the image. The deep feature information and the important feature information are then fused in the reconstruction layer. Furthermore, we also improve the algorithm structure of the loss function and discriminator to achieve a relatively optimal balance between the output image and the discriminator, so as to restore the super-resolution image closer to human perception. Our algorithm was validated on the public UCAS-AOD datasets, and the obtained results showed significantly improved performance compared to other methods, thus exhibiting a real advantage in supporting various image-related field applications such as navigation monitoring.

Photobiomodulation (PBM) refers to the beneficial effect produced from low-energy light irradiation on target cells or tissues. Increasing evidence in the literature suggests that PBM plays a positive role in the treatment of retinal diseases. However, there is great variation in the light sources and illumination parameters used in different studies, resulting in significantly different conclusions regarding PBM’s therapeutic effects. In addition, the mechanism by which PBM improves retinal function has not been fully elucidated. In this study, we conducted a narrative review of the published literature on PBM for treating retinal diseases and summarized the key illumination parameters used in PBM. Furthermore, we explored the potential molecular mechanisms of PBM at the retinal cellular level with the goal of providing evidence for the improved utilization of PBM in the treatment of retinal diseases.

Complex illumination, solar flares and heavy smog on the sea surface have caused difficulties to accurately obtain high-quality imaging and multi-dimensional information of marine monitoring targets, such as oil spill, red tide and underwater vehicle wake. The principle of existing imaging mechanism is complex, and thus it is not practical to capture high-resolution infrared images efficiently. To combat this challenge by utilizing new infrared optical materials and single point diamond-turning technology, we designed and processed a simple, light and strong condensing ability medium and long wavelength infrared imaging optical system with large relative aperture, which can obtain high-quality infrared images. On top of this, with the training from a combination of infrared and visible light images, we also proposed a super-resolution network model, which is composed of a feature extraction layer, an information extraction block and a reconstruction block. The initial features of the input images are recognized in feature extraction layer. Next, to supply missing feature information and recover more details on infrared image extracted from a dense connection block, a feature mapping attention mechanism is introduced. Its main function is to transfer the important feature information of the visible light images in the information extraction block. Finally, the global feature information is integrated in the reconstruction block to reconstruct the high-resolution infrared image. We experimented our algorithm on both of the public Kaist datasets and self-collected datasets, and then compared it with several relevant algorithms. The results showed that our algorithm can significantly improve the reconstruction performance and reveal more detail information, and enhance the visual effect. Therefore, it brings excellent potential in dealing with the problem of low resolution of optical infrared imaging in complex marine environment.

The clinical pharmacodynamics of tacrolimus in renal transplant patients has significant interindividual variability. T lymphocytes were selected to study the pharmacodynamic response of tacrolimus, which was significantly correlated with renal function and the outcome of renal transplant patients. Ultra-performance liquid chromatography–quadrupole time-of-flight mass spectroscopy (UPLC/Q-TOF-MS) was performed to obtain the metabolic profiles of 109 renal transplant patients. A partial least squares (PLS) model was constructed to screen potential biomarkers that could predict the efficacy of tacrolimus. Multinomial logistic regression analysis established a bridge that could quantify the relationship between the efficacy of tacrolimus and biomarkers. The results showed a good correlation between endogenous molecules and the efficacy of tacrolimus. Metabolites such as serum creatinine, mesobilirubinogen, L-isoleucine, 5-methoxyindoleacetate, eicosapentaenoic acid, N2-succinoylarginine, tryptophyl-arginine, and butyric acid were indicated as candidate biomarkers. In addition, the key biomarkers could correctly predict the efficacy of tacrolimus with an accuracy of 82.5%. Finally, we explored the mechanism of individual variation by pathway analysis, which showed that amino acid metabolism was significantly related to the efficacy of tacrolimus. Moreover, orthogonal partial least squares discriminant analysis (OPLS-DA) showed that there was no difference in key metabolites among different pharmacodynamic groups at 1 month and 3 months after dose adjustment, suggesting that pharmacometabonomics is a useful tool to predict individual differences in pharmacodynamics and thus to facilitate individualized drug therapy.

The microrheological phenomenon of kaolin-filled polypropylene (kaolin/PP) composites was investigated for the first time. The microviscosity of kaolin/PP composites was studied by changing the melt temperature and shear rate. Then, injection moulding experiments of rectangular microgrooves with different aspect ratios using kaolin/PP composites and mechanical property tests of the samples were carried out. The results showed that with increasing kaolin content, the microviscosity of the kaolin/PP composites gradually increases. The shear rate had the greatest influence on the microviscosity, and the kaolin content had the least influence. When the aspect ratio of rectangular microgrooves is small, with an increasing kaolin content, the microgroove filling rate increases, and the microstructured sample geometric shape replication effect is good; however, when the aspect ratio reaches 10:1, the microgroove filling rate decreases with an increasing kaolin content. The microstructured sample geometric shape replication effect is also poor, and size effects appear. Different factors control the microrheological morphology of composites with different aspect ratios, including the shear deformation and viscous flow of composites. The increase in kaolin content leads to a decrease in the friction coefficient and an increase in the wear resistance of the composites. We concluded that the best composite formulation for kaolin/PP composites in microinjection is the 7KL/PP composite with 7% kaolin. When the aspect ratio is 5:1, the reproduction of the microstructured sample geometry is the best, and the comprehensive mechanical properties of the sample are the best.

Venetoclax has emerged as a breakthrough for treatment of leukemia with a wide interindividual variability in pharmacokinetics. Herein, a rapid, sensitive, and reliable UPLC-MS/MS method for quantification of venetoclax in plasma was developed and validated. The method was operated in the multiple-reaction monitoring (MRM) mode to detect venetoclax at m/z transition 868.5 > 321.0 and IS at 875.5 > 321.0, respectively. Protein precipitation prior to injection into the LC-MS/MS and the analyte was separated on an ACQUITY UPLC BEH C18 column by gradient elution with acetonitrile and 0.1% formic acid in water. Linear calibration curves were obtained in the range of 25–8000 ng/mL. The specificity, recovery, matrix effect, and stability also met the acceptance criteria of FDA guidance. The method was successfully applied to analyze plasma in acute myeloid leukemia (AML) patients. The peak plasma concentration (Cmax) of venetoclax in Chinese AML patient was 2966.0 ± 1595.0 ng/mL while the trough concentration (Cmin) was 1018.0 ± 729.4 ng/mL. Additionally, Cmax and Cmin showed a positive correlation with AST levels. Furthermore, Cmax was significantly higher in the older patients. The present method can be applied for TDM of venetoclax in treatment of hematological cancers.

Polymeric optical sheets are significant components in large-scale display devices and are difficult to fabricate due to small size and high accuracy of large-area microstructures. As a newly developed molding technique, injection-rolling is capable of continuously and efficiently achieving large-area microstructures on the polymer surface with short time and high replication. However, the microstructure-forming mechanism during the injection-rolling process has not been fully understood. In this paper, a three-dimensional steady-state heat-flow coupling simulation model of the injection-rolling zone was established to obtain the distributions of the polymer state transition interfaces. According to the state transition interfaces, the entire microstructure-forming process was numerically simulated by dividing into filling and embossing stages to systematically analyze the effects of the polymer state transition interface on filling rate. After this, the relationship between process parameters such as injection temperature, rolling speed, and roll temperature and polymer state transition interface was investigated to develop a position prediction model of the state transition interface. In addition, the optical sheet injection-rolling experiments were also carried out to reveal that the filling rate of the microstructures on the optical sheet can be affected by varying the positions of the state transition interfaces. Therefore, the microstructure-forming mechanism could be revealed as theoretical guidance for the subsequent injection-rolling production with high quality and high efficiency.

The rejuvenation of Zr52.5Cu17.9Ni14.6Al10Ti5 bulk metallic glasses (BMGs) by ultrasonic vibration-assisted elastic deformation (UVEF) was studied herein. The UVEF-treated samples demonstrate an obvious rejuvenation and have a higher relaxation enthalpy and a smaller range of supercooled liquid regions than the as-cast samples. The fracture of the rejuvenated amorphous alloy is mainly ductile fracture, and shear deformation occurs in the deformation region. It is also found that as the amplitude increases, the free volume of the rejuvenated amorphous alloy increases, the yield strength and the elastic modulus decrease, and the formability increases. The free-volume content is used to characterize the degree of rejuvenation, and a mathematical model of the relationship between the ultrasonic amplitude and free volume is established. In addition, it is found that the ultrasonic vibration stress induces the additional free volume in the Zr-based bulk metallic glasses and improves the plasticizing behavior. The temperature rise caused by the ultrasonic thermal effect does not induce additional free volume.

Compared with laser-based 3D printing, fused deposition modelling (FDM) 3D printing technology is simple and safe to operate and has a low cost and high material utilization rate; thus, it is widely used. In order to promote the application of FDM 3D printing, poly-ether-ether-ketone (PEEK) was used as a printing material to explore the effect of multi-factor coupling such as different printing temperatures, printing directions, printing paths, and layer thicknesses on the tensile strength, bending strength, crystallinity, and grain size of FDM printed PEEK parts. The aim was to improve the mechanical properties of the 3D printed PEEK parts and achieve the same performance as the injection molded counterparts. The results show that when the thickness of the printed layer is 0.1 mm and the printing path is 180° horizontally at 525 °C, the tensile strength of the sample reaches 87.34 MPa, and the elongation reaches 38%, which basically exceeds the tensile properties of PEEK printed parts reported in previous studies and is consistent with the tensile properties of PEEK injection molded parts. When the thickness of the printed layer is 0.3 mm, the printing path is 45°, and with vertical printing direction at a printing temperature of 525 °C, the bending strength of the sample reaches 159.2 MPa, which exceeds the bending performance of injection molded parts by 20%. It was also found that the greater the tensile strength of the printed specimen, the more uniform the size of each grain, and the higher the crystallinity of the material. The highest crystallinity exceeded 30%, which reached the crystallinity of injection molded parts.

Taking the Poiseuille flow of a molten polymer in parallel plates as the research object and polymethyl methacrylate (PMMA) as the research material, an all-atom analysis model of the molecular dynamic flow of polymer macromolecules is established according to the Navier slip law. The effects of wall wettability and external pressure on the wall slip behaviour of polymer macromolecules, as well as the spatial evolution process of the entanglement–unentanglement process of polymer chains near the wall under different shearing effects, were studied. The interface thermal resistance rule was explored, and an interface thermal resistance model considering the wall slip behaviour was established. Finally, a micro-injection experiment was used to verify the validity and accuracy of the model. The results show that when the wall is hydrophobic, the polymer melt exhibits significant wall slip. As the external pressure increases, the wall slip speed and the slip length increase. However, after a certain pressure is exceeded, the growth rate of the slip length is basically zero. As the external pressure increases, the PMMA molecular chains gradually start to separate, the single molecular chain becomes untangled from the entangled grid, and the chain detaches from the wall after exceeding a certain threshold. Wall slip reduces the interface thermal resistance between the solid–liquid interface and enhances the interface heat transfer performance. The interface thermal resistance value calculated by molecular dynamics can more accurately reflect the heat conduction rule of the solid–liquid interface at the micro/nanoscale than that measured by the thermal resistance experiment, indicating that the micro/nano interface thermal resistance obtained by molecular dynamics simulation is reliable.

A new sintering method, namely ultrasonic assisted sintering (UAS), has been proposed using mechanical heat converted from high frequency motion between particles. Pure aluminum specimens with diameter of 5 mm and thickness of ~2 mm have been successfully sintered in two seconds. Based on the thermodynamic analysis, the underlying heating mechanism is quantitatively interpreted, which involves high-frequency interparticle friction and plastic deformation driven by ultrasonic squeezing. Consequently, temperature rises rapidly at a speed of about 300 K/s, and the maximum temperature reaches up to 0.9 times of melting point of the aluminum during UAS. The sintered specimens have a high density of dislocations, under the combined effects of dislocations and undulating stress field, volume diffusion coefficient for sintering increases by several orders of magnitude, therefore, rapid densification can be accomplished in seconds. In addition, the sintered aluminum has ultrahigh nanohardness (~1.13 GPa), which can be attributed to the hierarchical structure formed during UAS process.

Constructing regular micro-structures with certain geometric characteristics on the surface of the polymer part can obtain some specific functions. Micro ultrasonic powder molding (micro-UPM) is an efficient processing technique for the fabrication of well-filled micro-structured Polypropylene (PP) parts. The micro-structure array on the surface of the core insert was obtained by low speed wire electrical discharge machining (WEDM-LS). PP polymer surfaces with micro-structured patterns were successfully replicated from the core insert surface after micro-UPM. By studying the detailed topography characterizations of micro-structured PP parts, the effects of processing parameters (ultrasonic energy, welding pressure and holding time) on the micro-structured filling show that when PP polymer was formed under the conditions of 1000 J, 115 kPa and 8 s during micro-UPM, well-filled micro-structured parts can be obtained. Besides, without low surface energy coating modification, the water contact angles (WCAs) of micro-structured PP parts increased from 85.3° to 146.8°, indicating that the wettability of the surface can be changed by replicating the micro-structure on PP parts after micro-UPM.

A micro-ultrasonic (MU) viscosity model based on ultrasonic-assisted vibration micro-injection for high- flow length ratio polymer parts was established. This model considered the effects of ultrasonic energy and the characteristic microdimension. Ultrasonic energy parameters (such as the ultrasonic amplitude, frequency, and ultrasound velocity), the characteristic microdimension, and the molecular chain length (MCL) were introduced into the MU viscosity model. An ultrasonic micro-injection experimental platform was built on an injection molding machine. Polypropylene (PP) filling experiments were carried out using microgrooves with different flow length ratios (depth-to-width ratios of 3:1, 5:1, and 10:1). The validity and accuracy of the MU viscosity model were examined through a filling experiment with polypropylene (PP) microgroove injection molding and by a flow pressure difference experiment with polystyrene (PS). The results showed that the MU viscosity model was in better agreement with the experimental results compared to other models. The maximum error of the MU model was 4.9%. Ultrasound-assisted vibration had great effects on the filling capacity for microgrooves with high flow length ratios (depth-to-width ratios greater than 5:1). The filling capacity increased as the ultrasonic amplitude increased.

Stellera chamaejasme L. (Thymelaeaceae) is widely distributed in Mongolia, Tibet and the northern parts of China. Its roots are commonly used as “Langdu”, which is embodied in the Pharmacopoeia of the P.R. China (2010) as a toxic Traditional Chinese Medicine. It is claimed to have antivirus, antitumor and antibacterial properties in China and other Asian countries. Studies were carried out to characterize the inhibition of neochamaejasmin B (NCB) on P-glycoprotein (P-gp, ABCB1, MDR1). Rhodamine-123 (R-123) transport and accumulation studies were performed in MDCK-hMDR1 cells. ABCB1 (MDR1) mRNA gene expression and P-gp protein expression were analyzed. Binding selectivity studies based on molecular docking were explored. R-123 transport and accumulation studies in MDCK-hMDR1 cells indicated that NCB inhibited the P-gp-mediated efflux in a concentration-dependent manner. RT-PCR and Western blot demonstrated that the P-gp expression was suppressed by NCB. To investigate the inhibition type of NCB on P-gp, Ki and Ki’ values were determined by double-reciprocal plots in R-123 accumulation studies. Since Ki was greater than Ki’, the inhibition of NCB on P-gp was likely a mixed type of competitive and non-competitive inhibition. The results were confirmed by molecular docking in our current work. The docking data indicated that NCB had higher affinity to P-gp than to Lig1 ((S)-5,7-dihydroxy-2-(4-hydroxyphenyl)chroman-4-one).

In this paper, micro-structured polymer parts were efficiently and accurately fabricated by micro-injection molding using a micro-structured mold core machined by wire electrical discharge machining (WEDM). The objective was to realize low-cost mass production and manufacturing of micro-structured polymer products. The regular micro-structured mold core was manufactured by precise WEDM. The micro-structured polymer workpieces were rapidly fabricated by micro-injection molding and the effects of the micro-injection molding process parameters on replication rate and surface roughness of micro-structured polymers were systematically investigated and analyzed. It is shown that the micro-structured polymer can be rapidly and precisely fabricated by the proposed method. The experimental results show the minimum size machining error of the micro-structured mold core and the maximum replication rate of micro-formed polymer were 0.394% and 99.12%, respectively. Meanwhile, the optimal micro-injection molding parameters, namely, jet temperature, melt temperature, injection velocity, holding pressure and holding time were 195 °C, 210 °C, 40 mm/min, 7 Mpa and 5 s, respectively. The surface roughness Ra at the groove bottom and top of the micro-structured polymer workpieces achieved minimum values of 0.805 µm and 0.972 µm, respectively.

Precise micro-grinding machining was proposed to fabricate regular and controllable micro-grooved array structures on the surface of mold cores to realize the mass production and manufacturing of micro-structured polymer components by micro injection molding in this paper. First, the 3D topographies and section profiles of micro-ground mold cores and micro-formed polymers with different micro-structure parameters were presented. Then, the surface roughness of mold cores and polymers were compared. Next, the relationships between machining accuracy of mold core ground by micro-grinding and filling rates of micro-structured polymer formed by micro injection molding were investigated. Finally, the influences of micro injection molding parameters on the filling rate of micro-structures polymer were investigated. It is shown that the micro-structured polymer can be effectively and rapidly fabricated using the proposed method. The experimental results indicate the highest form accuracy of the micro-grooved mold core and the filling rate of micro-structured polymer can reach to 4.05 µm and 99.30%, respectively. It is found that the filling rate of the micro-structured polymer roughly increased with increasing machining accuracy of the mold core. The injection pressure had the greatest influence on the filling rate of the injection formed polymer, while the melt temperature had the least influence.