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To investigate the temperature characteristics of Laser-Assisted Cutting (LAC) in relation to cemented carbide, a theoretical model for LAC temperature was established based on heat conduction theory. Finite element simulations were conducted to analyze the surface temperature distribution and internal temperature distribution of cemented carbide during the LAC process. And an empirical formula for the LAC temperature of cemented carbide was obtained through temperature testing, and the model was experimentally validated. In addition the influences of the cutting temperature on the material machinability were experimentally studied. The results showed that the factors affecting cutting temperature ranked in order of importance are laser power, laser traversal speed, laser spot diameter, distance between cutting edge and spot center, cutting depth, and cutting speed. The cutting temperature trends were consistent under different processing parameters. In comparison with traditional cutting, the LAC method reduced the radial thrust force (Fx), tangential force (Fy), and axial thrust force (Fz) by 20.00, 27.14, and 53.19% respectively. The surface roughness of the workpiece was reduced by 50%, resulting in a flat and smooth surface with improved machinability. [ABSTRACT FROM AUTHOR]

The laser ultrasonic composite cutting (LUCC) process was proposed by combining laser heating-assisted cutting (LHAC) and elliptical ultrasonic vibration cutting (UVC). In the process of cutting experiment, cubic boron nitride (CBN) is selected as the tool's material. The wear morphology and wear appearance of the tools were observed by super depth-of-field microscopy and scanning electron microscopy (SEM) to research the wear characteristics and wear mechanism of CBN tools during LUCC of cemented carbide. Compared with conventional cutting (CC), UVC and LHAC, during LUCC of cemented carbide with CBN tools the tool wear are significantly reduced by 45.11%, 28.92%, and 17.39% respectively, the cutting force are decreased by 61%, 44%, and 46% respectively, and the surface roughness are lowered by 77%, 55%, and 62% respectively, therefore the tool life is obviously lengthened. Moreover, the tool flank wears model of during LUCC of cemented carbide was established and verified by the tool flank face wear test. The results show that when the CBN tool is used for LUCC of cemented carbide, the wear band on the tool's rake face is basically parallel to the cutting edge and is in the shape of a long strip, and the wear band on the tool's flank face shows a triangular-shaped wear band accompanied by shallow pits and grooves; In the process of the LUCC of cemented carbide, the main causes of CBN tool wear include adhesive wear, oxidation wear and abrasive wear are the main causes of CBN tool wear during LUCC of cemented carbide; The faster the cutting speed, the bigger the error among the experimental value with the calculated value, and the wear of tool's flank face during LUCC of cemented carbide gradually increased. [ABSTRACT FROM AUTHOR]

Eye movements have been extensively studied with respect to visual stimulation. However, we live in a multisensory world, and how the eyes are driven by other senses has been explored much less. Here, we review the evidence on how audition can trigger and drive different eye responses and which cortical and subcortical neural correlates are involved. We provide an overview on how different types of sounds, from simple tones and noise bursts to spatially localized sounds and complex linguistic stimuli, influence saccades, microsaccades, smooth pursuit, pupil dilation, and eye blinks. The reviewed evidence reveals how the auditory system interacts with the oculomotor system, both behaviorally and neurally, and how this differs from visually driven eye responses. Some evidence points to multisensory interaction, and potential multisensory integration, but the underlying computational and neural mechanisms are still unclear. While there are marked differences in how the eyes respond to auditory compared to visual stimuli, many aspects of auditory‐evoked eye responses remain underexplored, and we summarize the key open questions for future research. [ABSTRACT FROM AUTHOR]

A multiple model predictive control method based on membership function was proposed according to nonlinear characteristics of robot manipulator. An appropriate scheduling variable was selected according to the characteristics of the robot manipulator. The operation space of the robot manipulator was divided into several subspaces, the robot manipulator was linearized at equilibrium point in each subspace, and linear sub-models were built in each subspace, and the multiple model presentation of the robot manipulator was developed. Then, local predictive controllers were designed according to each linear sub-model, and make it satisfy with control requirements in the subspace. Finally, the local predictive controllers were combined by trapezoidal membership functions into a global multiple model predictive controller to control the robot manipulator. The simulation results show that the control performance of the global multiple model predictive controller based on the membership functions is superior to conventional PD controller when the robot manipulator was working in a wide operating range, so as to realize the desired control goal.

Transition metal dichalcogenides have been considered as candidate materials to construct logic‐in‐memory devices for realizing non‐von‐Neumann architecture. Thus, reducing the power consumption is extremely critical for their applications in big data and artificial intelligence. Here, a low‐power logic‐in‐memory device is demonstrated by constructing complementary inverter with p‐WSe2 and n‐WS2 transistors. By engineering the interface states between WSe2 (WS2) and substrate artificially, non‐volatile memory with resistance ratio of 104 and 103 after 500 s are achieved in individual WSe2 and WS2 transistors, respectively. Furthermore, a complementary inverter with a retention time longer than 500 s is realized by connecting p‐WSe2 and n‐WS2 transistors. More importantly, the static operating source‐drain current Ids of this inverter is around 0.5/0.1 nA at low/high resistance states with source‐drain voltage Vds = 5 V, and the hysteresis window is located around 0 V, both of which can reduce the energy consumption dramatically and leads to the low operation power. This work provides a convenient strategy to build a non‐von‐Neumann device toward post‐Moore information processing technology. [ABSTRACT FROM AUTHOR]

Until now, the metabolic effects of hepatitis B virus (HBV) replication on the progression of hepatic diseases (hepatitis, cirrhosis, and liver cancer) and liver functions have remained unexplored. Thus, a total of 199 hepatic disease patients with active and inactive HBV were enrolled in this study to explore serum metabolic characteristics using untargeted metabolomics. Multiple analyses, including principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), volcano plot and pathway analysis, were used for metabolic data analysis. Additionally, differential metabolites were analysed by commercial databases. A decrease of approximately 0.8-fold in amino acids (L-glutamic acid, D-glutamine and L-tyrosine) and an increase of 2-fold in phosphatidylcholines (PCs) and lysophosphatidylcholines (LPCs) were observed in hepatic disease patients with HBV replication. Moreover, downregulation of arachidonic acid, PC 34:2, sn-glycerol-3-phosphocholine, 1-palmitoylglycerophosphoinositol, and 1-oleoylglycerophosphoinositol by 0.6-fold was also found in the serum of patients with HBV replication. In addition, liver function was significantly different between cirrhosis patients with or without HBV replication (p <.05). In summary, this is the first study to focus on the metabolic changes induced by HBV replication in patients and to compare metabolic alterations in the progression of hepatic disease induced by HBV infection. High levels of amino acid depletion and PC and LPC biosynthesis were primarily observed, which may shed new light on the pathogenesis and treatment of HBV infection. [ABSTRACT FROM AUTHOR]

The human brain is sensitive to threat-related information even when we are not aware of this information. For example, fearful faces attract gaze in the absence of visual awareness. Moreover, information in different sensory modalities interacts in the absence of awareness, for example, the detection of suppressed visual stimuli is facilitated by simultaneously presented congruent sounds or tactile stimuli. Here, we combined these two lines of research and investigated whether threat-related sounds could facilitate visual processing of threat-related images suppressed from awareness such that they attract eye gaze. We suppressed threat-related images of cars and neutral images of human hands from visual awareness using continuous flash suppression and tracked observers' eye movements while presenting congruent or incongruent sounds (finger snapping and car engine sounds). Indeed, threat-related car sounds guided the eyes toward suppressed car images, participants looked longer at the hidden car images than at any other part of the display. In contrast, neither congruent nor incongruent sounds had a significant effect on eye responses to suppressed finger images. Overall, our results suggest that only in a danger-related context semantically congruent sounds modulate eye movements to images suppressed from awareness, highlighting the prioritisation of eye responses to threat-related stimuli in the absence of visual awareness., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Hu, Badde and Vetter.)

Objective: This study investigated the link between triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio and nonalcoholic fatty liver disease (NAFLD) and liver fibrosis in American adults., Methods: Information for 6495 participants from the National Health and Nutrition Examination Survey (NHANES) 2017-2020.03 was used for this cross-sectional study. The link between TG/HDL-C ratios and NAFLD and liver fibrosis was assessed by multiple linear regression before evaluating nonlinear correlations based on smoothed curve fitting models. Stratification analysis was then applied to confirm whether the dependent and independent variables displayed a stable association across populations., Results: TG/HDL-C ratios were positively correlated with NAFLD, with higher ratios being linked to increased prevalence of NAFLD. After adjusting for potential confounders, the odds ratios (OR) for NAFLD patients in the fourth TG/HDL-C quartile were 3.61 (95% confidence interval [CI], 2.94-4.38) ( P for trend < 0.001) in comparison with those in the first quartile after adjusting for clinical variables. However, no statistical significance was noted for the ratio for liver fibrosis after adjusting for potential confounders ( P for trend = 0.07). A nonlinear correlation between TG/HDL-C ratios and NAFLD was observed based on smoothed curve fitting models. However, a nonlinear relationship between the ratios and liver fibrosis was not established. In subgroup analyses, there was an interaction between smoking status and TG/HDL-C ratio in relation to the prevalence of liver fibrosis ( P for interaction < 0.001)., Conclusions: Among American adults, the TG/HDL-C ratio was noted to be nonlinearly positively associated with the prevalence of NAFLD; however, this relationship was not present in liver fibrosis., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Wang, Li, Wang, Shi, Hu, Zeng, Luo, Yang, Luo, Cao, Cai, Chen and Wang.)

Three-dimensional (3D) bioprinting is an important technology for fabricating artificial tissue. To effectively reconstruct the multiscale structure and multi-material gradient of natural tissues and organs, 3D bioprinting has been increasingly developed into multi-process composite mode. The current 3D composite bioprinting is a combination of two or more printing processes, and oftentimes, physical field regulation that can regulate filaments or cells during or after printing may be involved. Correspondingly, both path planning strategy and process control all become more complex. Hence, the computer-aided design and computer-aided manufacturing (CAD/CAM) system that is traditionally used in 3D printing system is now facing challenges. Thus, the scale information that cannot be modeled in the CAD process should be considered in the design of CAM by adding a process management module in the traditional CAD/CAM system and add more information reflecting component gradient in the path planning strategy., Competing Interests: The authors declare no conflicts of interest., (Copyright: © 2020 Zhang, et al.)