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The migration of photoinitiators (PIs): benzophenone (BP), ethyl 4-dimethylaminobenzoate (EDAB), and 4-chlorobenzophenone (CBP), from polyethylene (PE)-coated paper to 4% (v/v) acetic acid and 10% (v/v) salt-simulated food solution was quantitatively analyzed using gas chromatography–mass spectrometry. The migration behavior of the three PIs was studied under three specific working conditions: conventional heating, microwave power, and random vibration level. The migration rate of the three PIs in acidic food simulants was ranked from BP > EDAB > CBP under the specific working conditions. The mobility of the three PIs increased with increasing temperature, microwave power, and random vibration acceleration in 4% (v/v) acetic acid by 10, 10, and 15%, respectively. The experimental migration data of three PIs in PE-coated paper under different temperatures and microwave powers were used to establish the Crank monolayer migration model according to Fick’s second law. The diffusion coefficient D increased with an increase in experimental conditions. According to the migration data under the condition of random vibration level, a mathematical model conforming to the Fick model was established, fitting the migration process. These results showed that conventional heating, microwave heating, and vibration could affect the food safety of PE-coated paper.

Using the fluid dynamics model, we studied the formation of graphene surface plasma when the charge is tilted to the graphene sheet for motion. We calculated the electron energy loss spectrum of electrons at different angles and proved that the resonance in the spectrum is related to the frequency of graphene surface plasma, as the electron velocity decreases, the dispersion shifts to higher energies. An increase in the tilt angle will also shift the dispersion energy in a higher range.

In order to improve the quality of the Co-free high entropy alloy surface, a Co-free high entropy alloy specimen prepared by selective laser melting was polished by laser in this work. Optimal laser polishing process parameters were explored, and the best surface roughness Sa value reached 0.4626µm, which is much lower than the original surface roughness. Through microscope, SEM, EDS and other tests, the surface quality after polishing is obviously improved The big improvement in high entropy alloy specimen’ surface quality has potential significance in promoting the application of this material in high precision situations.

Aiming at the defects such as cracks in the polishing process of aluminum alloy 5052, the laser polishing of aluminum alloy 5052 was studied, and a new top-hat beam laser polishing method was proposed for aluminum alloy 5052. The energy distribution in the polishing process was well-distributed, which greatly improved the energy utilization efficiency and reduced the surface roughness. Confocal microscopy and SEM were used to obtain the microstructure and phase composition of the microstructures. The results showed that the surface roughness was considerably reduced to lengthen the service life of the aluminum alloy 5052 materials from an initial roughness of Sa = 3.9 μm to Sa = 1.32 μm after using top-hat fiber laser polishing.

Introduction: Inflammation is closely associated with the pathogenesis of vascular dementia (VD). Dl-3-n-butylphthalide (NBP) is a small molecule compound extracted from the seeds of Chinese celery, which have anti-inflammatory properties in animal models of acute ischemia and patients with stroke. In this experiment, we studied the protective effects of NBP in a rat model of VD induced by permanent bilateral occlusion of the common carotid arteries and investigated the role of the TLR-4/NF-κB inflammatory signaling pathway in the pathology of VD. Methods: The Morris water maze test was used to evaluate cognitive deficits in the VD rats. Western blot, immunohistochemistry, and PCR analyses were used to analyze the molecular basis of the inflammatory response. Results: NBP significantly improved the learning and memory ability of VD rats. With regard to the protective mechanism, the results showed that NBP significantly downregulated the relative expression of Cleaved Cas-1/Cas-1 and Cleaved GSDMD/GSDMD. Moreover, NBP decreased the levels of the TLR-4 and NF-κB (P65) protein and phosphorylation of P65 in the hippocampus of VD rats via the TLR-4/NF-κB signaling pathway. Conclusion: These findings demonstrate that NBP protects against memory deficits in permanent bilateral common carotid artery occlusion-induced VD rats by attenuating pyroptosis via the TLR-4/NF-κB signaling pathway.

Aim. Pirfenidone (PFD), an antifibrotic drug, has various beneficial functions such as antioxidant, antifibrotic, and anti-inflammatory effects. This study aimed to explore the molecular mechanisms underlying how PFD modulates retinal pigment epithelial (RPE) cells involved in neovascularization and subretinal fibrosis. Methods. ARPE-19 cell lines were treated with transforming growth factor-beta 2 (TGF-β2) alone or in combination with PFD. RPE cell viability, as a consequence of PFD use, was determined by the CCK-8 assay. Cell migration was assessed by the wound closure assay and quantified by the Image J software. Protein expression of the following markers was measured by the western blot analysis: an epithelial cell marker and E-cadherin; mesenchymal cell markers, fibronectin, matrix metalloprotein-9 (MMP-9), and alpha-smooth muscle actin (α-SMA); a fibrotic marker and connective tissue growth factor (CTGF); an angiogenesis marker and vascular endothelial growth factor (VEGF); NF-κB/Snail. The mRNA levels of fibronectin and α-SMA were determined by quantitative real-time PCR. VEGF was quantitatively measured by the enzyme-linked immunosorbent assay. Results. The cell viability assay revealed that PFD had no significant cytotoxic effect on RPE cells at concentrations of less than 1 mg/mL. The cell scratch assay showed that TGF-β2 stimulation significantly improved the migration of RPE cells and that PFD attenuated this effect. PFD significantly inhibited the TGF-β2-induced protein expression of E-cadherin and increased the TGF-β2-induced protein expression of fibronectin, MMP-9, α-SMA, CTGF, and VEGF in ARPE-19 cells. The mRNA expression of fibronectin and α-SMA was inhibited by PFD in TGF-β2-inducedARPE-19 cells. Additionally, the increased intracellular and supernatant expression of VEGF protein was suppressed by PFD. Mechanistically, RPE cells treated with PFD + TGF-β2 exhibited a decrease in phosphorylation of the NF-κB P65 subunit and activation of Snail, compared with the RPE cells treated with TGF-β2 alone. Conclusion. PFD ameliorated TGF-β2-induced neovascularization and fibrosis by suppressing the NF-κB/Snail signaling pathway. Therefore, PFD may be a potential drug in the treatment of age-related macular degeneration.

Too high or too low thyroid-stimulating hormone (TSH) has been associated with the progress and prognosis of coronary artery disease (CAD). However, whether TSH within its normal reference range plays a role in the severity of CAD remains unclear. In this observational study, we explored the potential relationship of hypersensitive TSH (hs-TSH) with the severity of CAD in euthyroid patients with or without diabetes mellitus. A total of 7357 CAD patients with euthyroidism were enrolled in this study. Of those, 1997 had diabetes mellitus. The severity of CAD was evaluated through the presence of myocardial infarction (MI) and the severity of coronary lesions, which was calculated using the Gensini score (GS). Logistic regression models treating hs-TSH as a categorical variable and restricted cubic spline analyses treating it as a continuous variable were used to evaluate the associations of hs-TSH with the severity of CAD. The propensity score matching method was used to further validate the differences between diabetic and nondiabetic patients. CAD patients with diabetes mellitus had lower levels of hs-TSH (1.6 (0.97–2.53) vs 1.67 (1.00–2.64)) in serum compared with CAD patients without diabetes mellitus. Meanwhile, hs-TSH was independently related to the severity of CAD. In CAD patients with vs without diabetes mellitus, the U-shaped relationship between hs-TSH and MI was more prominent in patients without diabetes mellitus, and the significant U-shaped association between higher GS and hs-TSH remained only in nondiabetes. Therefore, hs-TSH within the normal reference range has a U-shaped association with the severity of CAD in nondiabetic patients, which is markedly diluted in diabetic patients.

Tunable semiconductor lasers have many important applications such as wavelength division multiplexing, light detection and ranging, and gas detection. The increased interest in silicon photonics has led to the rapid development of miniaturized on-chip tunable semiconductor lasers. However, silicon has poor light-emitting properties. Therefore, realizing high-performance tunable semiconductor lasers requires the integration of light sources with silicon. In this study, we review silicon-based light source integration methods and the development of silicon-based integrated tunable semiconductor lasers. Considering that narrow-linewidth performance greatly expands the applications of tunable semiconductor lasers, methods for reducing the linewidth of tunable lasers are summarized. Finally, the development trends and prospects for silicon-based integrated light sources and silicon-based integrated tunable lasers are analyzed and discussed.

The behavior of a novel multimechanophore-functionalized graft copolymeric assembly in response to ultrasound stimulation was studied in detail.

The collision of a vehicle is often a process of strong nonlinearity and large deformation, and the finite element method is time-consuming. For this reason, a method of collision inversion research is proposed. Through the definition of the forward and inverse problems, the forward problem is inversely solved from the perspective of the inverse problem, and the collision process can be predicted quickly while the accuracy is ensured. In this paper, the idea of inversion is introduced into the collision test of the front bumper of the vehicle. First, a finite element model is established based on the geometric model of the bumper. The accuracy of the finite element model is verified by comparing the results of the drop weight test with the simulation results of the finite element model. Then, using the built simulation model, spring mass model and drop weight test, the inversion research of vehicle collision and the front bumper of a vehicle is carried out. The inversion research of the bumper first inverts the collision course in the inversion algorithm derived from the vehicle collision, and then compares the collision course derived from the inversion algorithm formula with the simulation test results. The research results show that the change trends of the time-velocity curve and the time-deformation curve obtained by the collision inversion algorithm are basically consistent with the simulation test results, indicating that the collision inversion algorithm can realize the rapid prediction of the collision course and improve derivation efficiency significantly, and it provides a new idea. Finally, under the constant energy condition of the drop weight test E = mgh, through the relationship between energy and deformation, it is concluded that the depth deformation of low-speed collision of the front bumper is greater than that of high-speed collision.

Cosmetics can beautify the skin and assist the treatment of skin diseases. Some methods have been developed to replace animal experiments for cosmetic screening. The microfluidic skin chip is considered as a effective tool for in vitro tests.

Long noncoding RNA (lncRNA) cardiac mesoderm enhancer-associated noncoding RNA ( CARMN) is a newly discovered tumor-suppressor lncRNA in cancers. However, its role in cervical cancer (CC) remains elusive. This study was conducted to analyze the molecular mechanism of CARMN in CC cell growth and provide a novel theoretical basis for CC treatment. RT-qPCR and clinical analysis revealed that CARMN and B-cell translocation gene 2 ( BTG2) were downregulated, whereas miR-92a-3p was upregulated in CC tissues and cells and their expressions were correlated with clinicopathological characteristics and prognosis. MTT assay, flow cytometry, and Transwell assays revealed that CARMN overexpression reduced proliferation, migration, and invasion and increased apoptosis rate in CC cells. Mechanically, CARMN repressed miR-92a-3p to promote BTG2 transcription. Functional rescue assays revealed that miR-92a-3p overexpression or BTG2 downregulation reversed the inhibitory role of CARMN overexpression in CC cell growth. Western blot analysis elicited that Wnt3a and β-catenin were elevated in CC cells and CARMN blocked the Wnt/β-catenin signaling pathway via the miR-92a-3p/BTG2 axis. Overall, our findings demonstrated that CARMN repressed miR-92a-3p to upregulate BTG2 transcription and then blocked the Wnt/β-catenin signaling pathway, thereby suppressing CC cell growth.

PurposeThis paper aimed a fractional-order sliding mode-based lateral lane-change control method that was proposed to improve the path-tracking accuracy of vehicle lateral motion.Design/methodology/approachIn this paper the vehicle presighting and kinematic models were established, and a new sliding mode control isokinetic convergence law was devised based on the fractional order calculus to make the front wheel turning angle approach the desired value quickly. On this basis, a fractional gradient descent algorithm was proposed to adjust the radial basis function (RBF) neuron parameter update rules to improve the compensation speed of the neural network.FindingsThe simulation results revealed that, compared to the traditional sliding mode control strategy, the designed controller eliminated the jitter of the sliding mode control, sped up the response of the controller, reduced the overshoot of the system parameters and facilitated accurate and fast tracking of the desired path when the vehicle changed lanes at low speeds.Originality/valueThis paper combines the idea of fractional order calculus with gradient descent algorithm, proposed a fractional-order gradient descent method applied to RBF neural network and fast adjustment the position and width of neurons.

Conventional data worth (DW) analysis for soil water problems depends on physical dynamic models. The widespread occurrence of model structural errors and the strong nonlinearity of soil water flow may lead to biased or wrong worth assessment. By introducing the nonparametric data worth analysis (NP-DWA) framework coupled with the ensemble Kalman filter (EnKF), this real-world case study attempts to assess the worth of potential soil moisture observations regarding the reconstruction of fully data-driven soil water flow models prior to data gathering. The DW of real-time soil moisture observations after Gaussian process training and Kalman update was quantified with three representative information metrics, including the trace, Shannon entropy difference and relative entropy. The sequential NP-DWA framework was examined by a number of cases in terms of the variable of interest, spatial location, observation error, and prior data content. Our results indicated that, similarly to the traditional DW analysis based on physical models, the overall increasing trend of the DW from the sequential augmentation of additional observations within the NP-DWA framework was also susceptible to interruptions by localized surges due to never-experienced atmospheric conditions (i.e., rainfall events). The difference is that this biased DW in the former is caused by model structural errors triggered by contrasting scenarios, which is difficult to be compensated for by assimilating more prior data, while this performance degradation in the NP-DWA can be effectively alleviated by enriching training scenarios or the appropriate amplification of observational noise under extreme meteorological conditions. Nevertheless, a substantial expansion of the prior data content may cause an unexpected increase in the DW of future potential observations due to the possible introduction of ensuing observation noises. Hence, high-quality and representative small data may be a better choice than unfiltered big data. Compared with the observations in the surface layer with the strongest time variability, the soil water content in the middle layer robustly exhibited remarkable superiority in the construction of model-free soil moisture models. We also demonstrated that the DW assessment performance was jointly determined by 3C, i.e., the capacity of potential observation realizations to capture actual observations, the correlation of potential observations with the variables of interest and the choice of DW indicators. Direct mapping from regular meteorological data to soil water content within the NP-DWA mitigated the adverse effects of nonlinearity-related interference, which thus facilitated the identification of the soil moisture covariance matrix, especially the cross-covariance.

A sequential modular hydrodynamic model integrated with detailed reaction kinetics (SMHM-RK) was developed and validated to predict tar and syngas components produced by the steam gasification of biomass in a fluidized bed gasifier. The simulations showed that the prediction accuracy is sensitive to both models for hydrodynamics and reaction kinetics. The simulations showed that the tar composition predicted by the SMHM-RK was more close to the measured values than those predicted by the well-mixed hydrodynamic model integrated with the same reaction kinetics (WMHM-RK). The predictions showed that the total tar decreased, but the polycyclic aromatic tar compounds increased with the increase in gasification temperature. There was an optimum steam-to-biomass ratio (SBR) for minimizing tar formation. The simulations found that the contents of total tar and heavy tar compounds decreased by increasing the SBR from 0.3 to 0.9, and then increased by further increasing the SBR. The injection of a small amount of oxygen in steam gasification cannot reduce tar formation. The injection of oxygen in steam gasification changed the reaction pathways of naphthalene to produce more naphthalene in the syngas. The de-volatilization rate affects pyrolytic volatile compositions and subsequent tar formation. Therefore, biomass devolatilization and homogeneous gas reactions should be solved simultaneously to accurately predict the syngas and tar composition.

A bearing is a critical component in the transmission of rotating machinery. However, due to prolonged exposure to heavy loads and high-speed environments, rolling bearings are highly susceptible to faults, Hence, it is crucial to enhance bearing fault diagnosis to ensure safe and reliable operation of rotating machinery. In order to achieve this, a rotating machinery fault diagnosis method based on a deep convolutional neural network (DCNN) and Whale Optimization Algorithm (WOA) optimized Deep Extreme Learning Machine (DELM) is proposed in this paper. DCNN is a combination of the Efficient Channel Attention Net (ECA-Net) and Bi-directional Long Short-Term Memory (BiLSTM). In this method, firstly, a DCNN classification network is constructed. The ECA-Net and BiLSTM are brought into the deep convolutional neural network to extract critical features. Next, the WOA is used to optimize the weight of the initial input layer of DELM to build the WOA-DELM classifier model. Finally, the features extracted by the Improved DCNN (IDCNN) are sent to the WOA-DELM model for bearing fault diagnosis. The diagnostic capability of the proposed IDCNN-WOA-DELM method was evaluated through multiple-condition fault diagnosis experiments using the CWRU-bearing dataset with various settings, and comparative tests against other methods were conducted as well. The results indicate that the proposed method demonstrates good diagnostic performance.

The active frequency drift (AFD) method is an effective method to detect islanding in grid-connected photovoltaic systems. However, it has some inherent drawbacks, such as generating higher harmonics. In order to reduce the harmonics and non-detection zone (NDZ), various improved AFD methods have been proposed, but they still suffer from high harmonics and reduced detection speed. To overcome these limitations, this paper proposes an innovative islanding detection technique based on AFD. Analysis reveals that the proposed method reduces harmonics by 68% compared to conventional AFD and has a larger chopping factor. Therefore, this technique offers several distinct advantages, including accelerated detection speed, reduced NDZ and harm caused by disturbances, and improved power quality. Furthermore, to verify the harmonic impact of this proposed islanding detection method, simulations and analyses are conducted using simulation software of Matlab/Simulink. An experimental prototype is set up in Laboratory. The simulation and experimental results demonstrate the superiority of the proposed method.

Maize is one of the most important economic crops in the world. The integrity of maize grains directly affects the economic value of the maize as a main commodity that depends on the percentage of grains broken (POGB) in mechanized harvesting. Decreasing grain processing breakage is key to achieving mechanical harvesting with high quality. It is difficult to ensure a low POGB, because it depends on different maize varieties, their moisture contents, threshing devices and harvester working speeds. In this paper, the effects of these factors on the POGB are investigated when the working speed of the harvester is 1.0 m·s−1, 1.5 m·s−1 and 2.0 m·s−1, respectively. The different threshing forms, including tangential-axial-flow (TAF), axial-flow with nail-tooth (AFN), axial-flow with rasp bar in big space (AFRBBS) and axial-flow with rasp bar in small space (AFRBSS), are summarized. The POGB of TAF was 5.4% and it was the lowest of four threshing devices when the working speed of the harvester was 1.0 m·s−1, which was suitable to thresh maize at a low working speed. Maize Demeiya No. 1 (DMYN1), XianDa205 (XD205), Demeiya No. 3 (DMYN3) and Hayu189 (HY189) were harvested at different harvester working speeds, and the POGB of maize DMYN1 was the lowest among the four maize varieties. The POGB increased with increases in the working speed of the harvester and the moisture content of the maize grains. The POGB reached a minimum value of 3.5% when maize XD205 with the lowest moisture content was harvested. The results can provide a reference for choosing the maize variety, its moisture content, the threshing device and the working speed of the harvester for decreasing grain processing breakage.