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It is indispensable to explore the appropriate level of surface residual stress to enhance the wear resistance of coated tools. TiAlSiN-coated carbide tools with dissimilar surface residual compressive stresses (− 300 ~ − 600 MPa) are acquired via micro-sandblasting, which are used in the high-speed sliding friction experiments and turning experiments. The influence of residual stress on the sliding wear and cutting wear performance of TiAlSiN coated tools is investigated. The results show that with the improvement of surface residual compressive stress (absolute value), the friction coefficient and wear rate are reduced. The sliding wear resistance of the coated tool is enhanced. In addition, the cutting performance of the tool is also improved with the increase of residual compressive stress (absolute value). However, the excessive surface residual compressive stresses (absolute value) can lead to severe coating peeling, which in turn impairs the capability of wear resistance. The TiAlSiN-coated carbide tool with the stress of − 500 MPa presents the best wear resistance in the high-speed sliding wear and cutting wear process. [ABSTRACT FROM AUTHOR]

Low-voltage soft actuators with large displacement, long actuation durability, and fast response time have aroused great attention in soft robotics, wearable devices, haptic devices, and implantable or disposal biomedical devices. Herein, we report a low-voltage electroactive ionic soft actuator based on the sulfonated cellulose nanowhisker (SCN), microfibrillated cellulose (MFC), ionic liquids (IL), and graphene nanoplatelet (GN). The proposed SCN/MFC-IL-GN (0.1wt%) actuator demonstrated a large bending displacement (6.6 mm under ± 1 V sinusoidal input signal at 0.1 Hz, low driving voltage (as low as 0.25 V), wide actuation frequency (0.1 to 5.0 Hz), and long actuation durability (96.7% retention for 1 h), all of which stemmed from the strong crosslinking and ionic interactions among the functional sulfonated groups of SCN, hydroxyl groups of MFC, IL, and GN. Furthermore, the designed actuator was successfully employed to imitate the human finger's behaviors including turning on/off the flashlight and sliding electronic photographs on a smart phone screen. Therefore, the proposed SCN/MFC-IL-GN actuator has great potential in artificial muscles, soft robots, haptic devices, and wearable devices because of its low excitation voltage, large bending displacement, long actuation durability, and biofriendly property. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) prevention requires early detection and removal of adenomas. We aimed to develop a computational model for real-time detection and classification of colorectal adenoma. Computationally constrained background based on real-time detection, we propose an improved adaptive lightweight ensemble model for real-time detection and classification of adenomas and other polyps. Firstly, we devised an adaptive lightweight network modification and effective training strategy to diminish the computational requirements for real-time detection. Secondly, by integrating the adaptive lightweight YOLOv4 with the single shot multibox detector network, we established the adaptive small object detection ensemble (ASODE) model, which enhances the precision of detecting target polyps without significantly increasing the model's memory footprint. We conducted simulated training using clinical colonoscopy images and videos to validate the method's performance, extracting features from 1148 polyps and employing a confidence threshold of 0.5 to filter out low-confidence sample predictions. Finally, compared to state-of-the-art models, our ASODE model demonstrated superior performance. In the test set, the sensitivity of images and videos reached 87.96% and 92.31%, respectively. Additionally, the ASODE model achieved an accuracy of 92.70% for adenoma detection with a false positive rate of 8.18%. Training results indicate the effectiveness of our method in classifying small polyps. Our model exhibits remarkable performance in real-time detection of colorectal adenomas, serving as a reliable tool for assisting endoscopists. [ABSTRACT FROM AUTHOR]

Triaxial braided composites employed as structural components need to be drilled for mechanical connections. This study is to investigate the thrust force, temperature elevation, and drilling-induced damages with varying machining parameters in the drilling of triaxial braided CFRP. A high-resolution infrared thermography was carried out to capture the temperature of the panel side surface and the drill-exit surface of CFRP. The damage characteristic of drilled hole was evaluated, and a relationship between force, temperature, and hole damage was established. The obtained results indicate that the temperature of triaxial braided CFRP was mainly transferred along the fiber direction. The temperature isothermal at the drill-exit surface developed from polygonal to roughly circular with the increase of drilling depth. The braided yarns tended to deflect, and induced poorly cut fibers due to the more heat generation with the low feed, making the matrix behaved from brittle to ductile and therefore resulting in more burrs. The increase of spindle speed could restrain the burrs. A larger thrust force with high feed will result in fiber-resin debonding and more tearing defects. The delamination occurred at the interface of fiber bundles at the outermost layer with high thrust force and cracks propagated along the yarn direction. [ABSTRACT FROM AUTHOR]

Deep brain stimulation (DBS) has improved the prospects for many individuals with diseases affecting motor control, and recently it has shown promise for improving cognitive function as well. Several studies in individuals with Alzheimer disease and in amnesic rats have demonstrated that DBS targeted to the fimbria-fornix, the region that appears to regulate hippocampal activity, can mitigate defects in hippocampus-dependent memory. Despite these promising results, DBS has not been tested for its ability to improve cognition in any childhood intellectual disability disorder. Such disorders are a pressing concern: they affect as much as 3% of the population and involve hundreds of different genes. We proposed that stimulating the neural circuits that underlie learning and memory might provide a more promising route to treating these otherwise intractable disorders than seeking to adjust levels of one molecule at a time. We therefore studied the effects of forniceal DBS in a well-characterized mouse model of Rett syndrome (RTT), which is a leading cause of intellectual disability in females. Caused by mutations that impair the function of MeCP2 (ref. 6), RTT appears by the second year of life in humans, causing profound impairment in cognitive, motor and social skills, along with an array of neurological features. RTT mice, which reproduce the broad phenotype of this disorder, also show clear deficits in hippocampus-dependent learning and memory and hippocampal synaptic plasticity. Here we show that forniceal DBS in RTT mice rescues contextual fear memory as well as spatial learning and memory. In parallel, forniceal DBS restores in vivo hippocampal long-term potentiation and hippocampal neurogenesis. These results indicate that forniceal DBS might mitigate cognitive dysfunction in RTT. [ABSTRACT FROM AUTHOR]

Leakage dissolution is one of the potential threats to the long-term operating safety of a dam. The aim of this paper is to analyze the characteristics of leakage dissolution around the dam foundation of Qingju Hydropower Station and evaluate its engineering influence based on laboratory testing and in situ monitoring. Comparative analysis of water samples in 20 representative positions shows that the bedrock of the dam foundation has been enduring obvious dissolution under the effects of the groundwater. In situ monitoring data of displacement and leakage during the period from 2005 to 2013 indicates that there has been no excessive deformation, obvious uneven settlement, or concentration leakage in these nine years, and; therefore, the leakage dissolution of the dam foundation has not resulted in critical danger to the safety of dam so far. However, with an annual amount of gypsum dissolution discharged by the drainpipes of about $$ 1.82 \times 10^{5}\,{\rm kg} $$ , long-term leakage dissolution may be hazardous, besides the higher content of SO than normal in the groundwater of the dam foundation caused by leakage dissolution may invoke some crystal corrosion and decrease the durability of the concrete structures. To guarantee the long-term safety of the dam, implementing grouting is proposed to prevent dissolution or slow down the dissolution rate on the basis of real-time monitoring and feedback. [ABSTRACT FROM AUTHOR]

Mutations in SHANK3 and large duplications of the region spanning SHANK3 both cause a spectrum of neuropsychiatric disorders, indicating that proper SHANK3 dosage is critical for normal brain function. However, SHANK3 overexpression per se has not been established as a cause of human disorders because 22q13 duplications involve several genes. Here we report that Shank3 transgenic mice modelling a human SHANK3 duplication exhibit manic-like behaviour and seizures consistent with synaptic excitatory/inhibitory imbalance. We also identified two patients with hyperkinetic disorders carrying the smallest SHANK3-spanning duplications reported so far. These findings indicate that SHANK3 overexpression causes a hyperkinetic neuropsychiatric disorder. To probe the mechanism underlying the phenotype, we generated a Shank3 in vivo interactome and found that Shank3 directly interacts with the Arp2/3 complex to increase F-actin levels in Shank3 transgenic mice. The mood-stabilizing drug valproate, but not lithium, rescues the manic-like behaviour of Shank3 transgenic mice raising the possibility that this hyperkinetic disorder has a unique pharmacogenetic profile. [ABSTRACT FROM AUTHOR]