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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]

In this paper, the effect of axial yarns on progressive bending damage of braided composite tubes is predicted by simulation. In this paper, Abaqus mesoscopic finite element simulation of lateral collapse of biaxial and triaxial braided composite tubes is carried out. Firstly, the specific material parameters of impregnated yarn and resin were determined by micro-scale periodic unit cell (RUC) model and experiment, and the material properties of resin matrix and impregnated yarn were defined. In the simulation, the resin failure process was simulated according to the ductility and shear damage criteria, and the damage of fiber reinforcement was predicted according to the Hashin criteria. The simulation results show a good correlation with the experimental results, indicating that the Abaqus simulation model established in this paper can further explain the bending damage evolution behavior of biaxial and triaxial braided pipes, and further understand the damage mechanism of braided composite tubes. At the same time, the addition of axial yarn greatly improves the bearing stress and energy absorption capacity of braided composite tube. Finally, the experimental and simulated damage profiles of the two samples were compared. [ABSTRACT FROM AUTHOR]

The accuracy of the original YOLOv5 algorithm in detecting whether power company employees are wearing helmets is low due to the complex monitoring scenarios in the power warehouse and the small size of the helmets. As a result, it cannot be applied to actual operations. To address this issue, we developed the MCX-YOLOv5 helmet detection algorithm. Our model utilizes the YOLOv5 architecture and integrates a Coordinate-Spatial Attention Module (CSAM) to effectively filter the spatiotemporal data of the feature inputs. Additionally, we implement a Multi-scale Asymmetric Convolutions (MAConv) downsampling module to improve the algorithm's sensitivity to feature scale variations. To address the challenge of task information cross-coupling in coupled heads, we propose a decoupled head that is less heavy than YOLOv6 as a substitute. Our enhanced model achieved a 2.7% rise in the mean Average Precision at 50 (mAP50) and a 4.9% improvement in mAP75 on our self-developed database through multiple experiments, with just a minimal increase in parameters. Our model has yielded significant performance improvements on the Kaggle open-source Hard Hat Workers Detection dataset (HHWD), the public Safety Helmet Wearing Dataset (SHWD), and the PASCAL Visual Object Classes (VOC) dataset. These results highlight the effectiveness of our proposed algorithm in achieving higher accuracy for safety helmet wear detection in storage scenarios. [ABSTRACT FROM AUTHOR]

A trajectory comparison method is proposed to study the impact of back-gate radiation on single-event effects (SEE) of ultrathin body and buried oxide (UTBB) fully depleted silicon-on-insulator (FDSOI) MOSFETs using Synopsys Sentaurus technology computer-aided design (TCAD) tools. Based on the series coupling capacitance model of the threshold voltage, the influence of device parameters such as buried oxide (BOX) thickness, ground plane doping and back biasing on the back-gate radiation effect is analyzed. The electrostatic potential difference between the BOX/substrate interface and substrate region decreases due to the reduced width of the substrate depletion region caused by back-gate radiation, leading to a positive shift in the threshold voltage and a decrease in the transient leakage current. The back-gate radiation effect is enhanced with reduced BOX layer thickness and ground-plane doping. UTBB FDSOI devices under reverse back biasing from 0 V to −0.5 V, which expands the depletion region, show a more dramatic decrease in the transient leakage current than those under forward back biasing. The findings contribute to a better understanding of the SEE mechanism of UTBB FDSOI devices and are helpful in radiation hardness optimization. [ABSTRACT FROM AUTHOR]

Mg/Al composites were successfully fabricated by the differential temperature + asymmetrical rolling (DTAR) and the isothermal + symmetrical rolling (ISR), respectively. The effects of DTAR and ISR on the tensile properties, bonding strength, interface morphology, and microstructure of composite plates were investigated. The results indicated that grains near the Mg layer of the Mg/Al interface were fine and equiaxed because of the occurrence of dynamic recrystallization on the Mg layer. In contrast, the grains at the center and near the Al side interface were elongated. DTAR enhanced the recrystallization degree of Mg side grains. The tensile properties and bonding strength of the composite plates increased gradually with increase in reduction rate, while the interface morphology was gradually flat with increase in reduction rate. The ultimate tensile strength of DTAR sample reaches 205 MPa, which is 25% higher than that of ISR sample. [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]

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]

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]

A novel gas diffusion electrode (GDE) electrolyzer has been constructed to convert CO2 into CO, with chlorine (Cl2) and sodium carbonate (Na2CO3) produced as the by-products. Using this method, the product value yielded from CO2 electrolysis can be increased substantially. In contrast to the conventional GDE electrolyzer, we use a cation-exchange membrane as the diaphragm to separate the cathode from the anode compartment, and use NaCl aqueous solution as the anolyte. During the electrolysis process, CO2 is reduced to CO on the cathode, with CO32− generated accompanied with CO formation. On the anode, Cl− is oxidized to Cl2. Na+ in the anode chamber transfers through the cation-exchange membrane, and migrates into the catholyte. Thus, Na2CO3 can be obtained owing to the co-existing of Na+ and CO32− in the catholyte. Using this method, CO32− penetrating through the anion-membrane can be avoided. This problem has been considered as the crucial obstacle that impedes the practical utilization of the conventional GDE electrolyzer. Our designed GDE electrolyzer has a promising application perspective in the phosgene chemical industry. [ABSTRACT FROM AUTHOR]

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In this paper, we simulate the electrical characteristics of the n-type metal-oxide-semiconductor (NMOS) transistor in a 65-nm complementary metal-oxide-semiconductor (CMOS) inverter under the actions of heavy ions with different linear energy transfers (LET). We analyze the influence of incident ions with different LETs on a device using technology computer-aided design (TCAD) software, and aim to establish an HSPICE sub-circuit model containing the relationship between the electrical properties of a device and the LET of an incident ion for circuit-level HSPICE simulation. Based on the SEE funnel mechanism, we propose an analytical model to describe the relationship between the charge collected by the NMOS drain and the LET of the incident ion, and build an HSPICE model based on this analytical model. With such a model, the influence of incident ions with different circuit-level LETs can be determined from HSPICE simulation. In addition, good agreement with simulation results is reached, proving the reasonableness of the proposed model. [ABSTRACT FROM AUTHOR]

SiO2@TiO2-Ag (STA) microspheres decorated with Ag nanoparticles (Ag NPs) were prepared and assembled into the photoanode. The photoanode composed of STA microspheres and TiO2 nanoparticles (P25) was prepared by doctor blade method. UV–vis measurement indicates that the introduction of a few STA microspheres observably enhances the light scattering and capturing ability of the photoanode. The photoelectric conversion efficiency of the DSSCs with 2wt% STA photoanode increased to 7.4% from 4.3% comparing with pure P25 TiO2 nanoparticles. The configuration DSSCs have the maximum short circuit current density (Jsc) of 16.0 mA cm−2 and open-circuit voltage (Voc) of 0.780 V, which are significantly higher than the pure TiO2 DSSCs. The significant improvement of the DSSCs performance can be due to the synergistic effect of the superior light scattering of STA and the localized surface plasma resonance (LSPR) effect of Ag NPs modified on the microspheres surface. [ABSTRACT FROM AUTHOR]

It is important to control exoskeleton to act synchronously with the user for movement assistance. A knee exoskeleton was constructed for gait rehabilitation training, and a control method based on adaptive frequency oscillator (AFO) was presented for swing motion of knee exoskeleton. Firstly, during the learning mode, the user flexed and extended with the exoskeleton leg together, and the exoskeleton leg was not actuated. The phase of the exoskeleton angle extracted, and the envelope curve of the user's EMG is generated based on AFO. Then, during power-assisted mode, the assistive torque is generated according to the angle phase on-line and the restructuring muscle torque. At last, the assistive torque as a feedback signal was input to the admittance model for the swing control of the knee exoskeleton. The experiments of swing control showed that knee exoskeleton can follow the user's motion well. [ABSTRACT FROM AUTHOR]

In this paper, a novel numerical simulation framework using meso-scale finite element model is developed to predict the mechanical properties and damage mechanisms for one-layer biaxial braided composite tubes with gradient braided structures in axial direction, which involves braided reinforcements with an evolution of braiding angle. To bridge the relationships between the braiding procedure and geometric model, this paper develops an automatic algorithm that generates the geometric model with requiring braiding parameters as input parameters. The braided fabric model is generated by circularly arraying the yarn model, which is established by sweeping varying cross-sections along the centerline with the control of guidelines. The geometric model of matrix pockets is obtained by extracting the fabric model from the whole geometric model of composite tube. After that, a braiding yarn mesh in hexahedron format and co-node matrix mesh in tetrahedron format are generated from the assembled braided fabric and matrix pockets. The framework established in this paper is validated by comparison with the experimental results of the composite tubes with braiding angles from 36.6° to 49.6° subjected to quasi-static axial compression. [ABSTRACT FROM AUTHOR]

The characteristics and mechanism of single-event transients in silicon-on-insulator (SOI) fin field-effect transistors (FinFETs) were analyzed using Sentaurus technology computer-aided design (TCAD) simulations based on the bipolar amplification effect. The results show that a typical single pulse mode of the transient leakage current is observed. The peak current and collected charge increase approximately linearly with increase of the linear energy transfer. The electric field in the depletion region of the FinFET body-drain junction increases significantly when the drain bias increases, resulting in a sharp increase in the drift current until reaching the saturation state. The variation of the bipolar gain and transient current with the position of incidence of the particle shows good consistency, reaching a maximum in the FinFET drain region, which indicates that the drain depletion region of SOI FinFETs is most sensitive to heavy-ion irradiation due to the bipolar amplification effect. The bipolar gain increases with decrease of the gate length and increase of the fin height and width. [ABSTRACT FROM AUTHOR]

A 3D model of the negative-channel metal-oxide semiconductor (NMOS) structure in a 65-nm complementary metal-oxide semiconductor (CMOS) inverter was built based on technology computer-aided design (TCAD) three-dimensional (3D) device simulation software. The single-event effect caused by a heavy ion at different incident positions was simulated and analyzed using the TCAD-HSPICE mixed-mode simulation. Then, an analytical model was established to describe the relationship between the incident position of the ion and the charge collected by the NMOS drain. Finally, an HSPICE simulation approach based on this model was developed and verified by simulations. [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]

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]

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]

We examine the dynamics between enforcement actions and the responses from both the board of directors and supervisory boards amid China's governance reform. Rather than examining determinants of fraudulent activities, we investigate, after enforcement actions are imposed, whether the board of directors and supervisory boards react differently, and whether their different reactions play a role in preventing future occurrences of frauds. We find that both boards react to enforcement actions, but only the responses from the board of directors help us curb future enforcements under certain circumstances. The supervisory board fails to play any role in preventing future enforcements, even though it is one of the two monitoring mechanisms in the listed companies. Policy implications are discussed. [ABSTRACT FROM AUTHOR]

We examine enforcement action in China’s emerging markets by focusing on (1) the agents that impose this action and (2) the role played by supervisory boards. Using newly available databases, we find that supervisory boards play an active role when Chinese listed companies face enforcement action. Listed firms with larger supervisory boards are more likely to have more severe sanctions imposed upon them by the China Security Regulatory Commission, and listed companies that face more severe enforcement actions have more supervisory board meetings. Our findings are of interest, as supervisory boards in China are generally perceived to be dysfunctional. This study contributes to the existing literature in three ways. First, we shed light on the effects of supervisory boards whose role in a fraud setting has not yet been examined. Second, the study has important policy implications for governance reform. Finally, our analyses provide the most up-to-date picture of fraud and governance issues in China’s ever-growing markets. [ABSTRACT FROM AUTHOR]

Valuing high-dimensional options has many important applications in finance but when the true distributions are unknown or complex, numerical approximations must be used. Approximation methods based on Monte-Carlo simulation show a steep trade-off between estimation accuracy and computational efficiency. This article presents an alternative semi-analytic approximation method for pricing options on the maximum or minimum of multiple assets with unknown distributions. Computational efficiency is shown to improve significantly without sacrificing estimation accuracy. The method is illustrated with applications to options on underlying assets with mean-reverting prices, time-dependent correlations, and stochastic volatility [ABSTRACT FROM AUTHOR]

Human exposure to pathogenic viruses in environmental waters results in a significant global disease burden. Current microbial water quality monitoring approaches, mainly based on fecal indicator bacteria, insufficiently capture human health impacts posed by pathogenic viruses in water. The emergence of the 'microbiome era' and high-throughput metagenome sequencing has led to the discovery of novel human-associated viruses, including both pathogenic and commensal viruses in the human microbiome. The discovery of novel human-associated viruses is often followed by their detection in wastewater, highlighting the great diversity of human-associated viruses potentially present in the water environment. Novel human-associated viruses provide a rich reservoir to develop viral water quality management tools with diverse applications, such as regulating wastewater reuse and monitoring agricultural and recreational waters. Here, we review the pathway from viral discovery to water quality monitoring tool, and highlight select human-associated viruses identified by metagenomics and subsequently detected in the water environment (namely Bocavirus, Cosavirus, CrAssphage, Klassevirus, and Pepper Mild Mottle Virus). We also discuss research needs to enable the application of recently discovered human-associated viruses in water quality monitoring, including investigating the geographic distribution, environmental fate, and viability of potential indicator viruses. Examples suggest that recently discovered human pathogens are likely to be less abundant in sewage, while other human-associated viruses (e.g., bacteriophages or viruses from food) are more abundant but less human-specific. The improved resolution of human-associated viral diversity enabled by metagenomic tools provides a significant opportunity for improved viral water quality management tools. [ABSTRACT FROM AUTHOR]