Nanopore detection is a hot issue in current research. One of the challenges is how to slow down the transport velocity of nanoparticles in nanopores. In this paper, we propose a functional group ...modified nanopore. That means a polyelectrolyte brush layer is grafted on the surface of the nanopore to change the surface charge properties. The existing studies generally set the charge density of the brush layer to a fixed value. On the contrary, in this paper, we consider an essential property of the brush layer: the volume charge density is adjustable with pH. Thus, the charge property of the brush layer will change with the local H+ concentration. Based on this, we established a mathematical model to study the transport of nanoparticles in polyelectrolyte brush layer modified nanopores. We found that pH can effectively adjust the charge density and even the polarity of the brush layer. A larger pH can reduce the transport velocity of nanoparticles and improve the blockade degree of ion current. The grafting density does not change the polarity of the brush charge. The larger the grafting density, the greater the charge density of the brush layer, and the blockade degree of ion current is also more obvious. The polyelectrolyte brush layer modified nanopores in this paper can effectively reduce the nanoparticle transport velocity and retain the essential ion current characteristics, such as ion current blockade and enhancement.
The protonation and deprotonation reactions in the brush layer will change the charge properties of the brush layer, and then affect the transport of particles in the nanopores. Display omitted
Rolling bearing fault diagnosis is one of crucial tasks in mechanical equipment fault diagnosis. Currently, artificial intelligence and machine learning-driven fault diagnosis methods are extensively ...utilized for rolling bearing. When compared to traditional techniques, the diagnostic accuracy has significantly improved. These methods, however, need a substantial amount of labelled training data, which is difficult to obtain in actual failures. In order to resolve this problem, Transfer Learning (TL) was created to learn in the target domain by accessing knowledge from the pertinent labelled source domain. Inspired by Maximum Mean Discrepancy, this paper puts forward a Convolutional Neural Network (CNN) based Two-layer Transfer Learning (CTTL) method for fault diagnosis. In the first layer, the fault features are automatically extracted by CNN and a term called Feature Weighted Maximum Mean Discrepancy (WMMD) is considered to minimise the difference between source and target domains. In the second layer, the Third Dataset, which is based on the Density-Based Spatial Clustering of Applications with Noise (DBSCAN) method was designed on the basis of the predicted labels from the first layer. The Calinski-Harabaz (CH) index of the Target Dataset controls the iteration times of CTTL. CTTL change the process of Transfer Learning method from learning the distribution of domains to learning the distribution of fault types in more detail, which will get higher accuracy. Proposed CTTL is tested by the bearing datasets of Case Western Reserve University (CWRU) and XJTU-SY. The experimental findings reveal that CTTL is capable of achieving a high diagnosis accuracy across different load domains. In the majority of experiments, CTTL outperformed other algorithms, including Deep Neural Network, Support Vector Machine, and several other methods.
In order to explore the relationship of social support, self-efficacy, and subjective well-being of special education teachers in China, 496 teachers from 67 special education schools were surveyed ...by questionnaire. We found that (1) the subjective well-being of special education teachers in China was in the medial level. (2) There were significant differences in subjective well-being level among teachers of different genders, teacher position, education background, and teaching age. Male teachers were of higher subjective well-being; subjective well-being of head teachers was lower than those were not head teachers; teachers with the educational background of postgraduate were of higher relaxation and tension than those with junior college educational background; the control scores of emotion and behavior of teachers with teaching age of 3 years and below were significantly lower than those of teachers with teaching age of more than 10 years. (3) Self-efficacy played a partially mediating role in the relationship between social support and subjective well-being of special education teachers. Suggestions to improve the subjective well-being of special education teachers were discussed in the article.
Immunotherapy has improved the clinical outcomes of patients with advanced non-small cell lung cancer (NSCLC). However, in patients with Kirsten rat sarcoma viral oncogene homolog (
) mutations, the ...superior efficacy of immunotherapy has not been elucidated and especially in real-world practice. Our study aimed to use real-world data to assess the efficacy of immunotherapy in
-mutant NSCLC in a Chinese cohort.
In this retrospective cohort study, we extracted the clinical, molecular, and pathologic data from the electronic health records of patients with advanced
-mutant NSCLC at Shandong Cancer Hospital between January 2018 and May 2022. Furthermore, we evaluated the progression-free survival (PFS) and overall survival (OS) of the included patients.
Between January 2018 and November 2020, 793 patients were identified with stage IIIB-IV NSCLC and a total of 122 patients with
mutations were included in the analysis. The majority of patients were diagnosed with stage IV (82.0%) adenocarcinoma (93.4%), along with a history of smoking (57.4%). Of these, 42% of patients received anti-PD-(L)1 with or without chemotherapy (Immunotherapy-based regimens), while 58.2% of patients received chemotherapy (Chemotherapy-based regimens). The median overall survival (mOS) in this cohort was 22.9 months (95% CI: 14.1-31.7), while the median-progression-free survival (mPFS) was 9.4 months (95% CI: 6.6-12.1). Patients receiving immunotherapy-based regimens displayed better mOS than those receiving chemotherapy-based regimens (45.2 vs. 11.3 months;
=1.81E-05), with no statistical difference observed in the mPFS (10.5 vs. 8.2 months;
=0.706). Patients receiving immunotherapy-based regimens either in the first line (
=0.00038,
=0.010, respectively) or second-line setting (
=0.010,
=0.026, respectively) showed benefits in both PFS and OS. Subgroup analysis indicated that in patients having
G12C or non-
G12C mutant types, immunotherapy showed benefits of better OS (
=0.0037,
=0.020, respectively) than chemotherapy. Moreover, in advanced NSCLCs patients with or without
co-mutation the immunotherapy-based regimen achieved longer OS and PFS than chemotherapy-based regimens.
In the Chinese population of patients with
-mutant advanced NSCLC, immunotherapy-based regimens achieved longer OS than chemotherapy-based regimens, which was independent of first or second-line setting, as well as
mutational subtypes.
The electric transport of nanoparticles passing through nanopores leads to a change in the ion current, which is essential for the detection technology of DNA sequencing and protein determination. In ...order to further illustrate the electrokinetic transport mechanism of particles passing through nanopores, a fully coupled continuum model is constructed by using the arbitrary Lagrangian–Eulerian (ALE) method. The model consists of the electric field described by the Poisson equation, the concentration field described by Nernst–Planck equation, and the flow field described by the Navier–Stokes equation. Based on this model, the influence of imposed electric field and particle length on the electrokinetic transport of cylindrical particles is investigated. It is found firstly the translation velocities for the longer particles remain constant when they locate inside the nanopore. Both the ion current blockade effect and the ion current enhancement effect occur when cylindrical particles enter and exit the nanopore, respectively, for the experimental parameters employed in this research. Moreover, the particle translation velocity and current fluctuation amplitude are dominated by the electric field intensity, which can be used to adjust the particle transmission efficiency and the ion current detectability. In addition, the increase in particle length changes the particle position corresponding to the peak value of the ion current, which contributes to distinguishing particles with different lengths as well.
This paper examined pilots' risk-taking behavioural intentions based on the theory of planned behaviour, as well as the impact of experience on behavioural intentions in adverse weather conditions. ...Two hundred and seventy-three airline pilots and flying cadets were divided into two groups and asked to complete a questionnaire based on two decision-making scenarios. This questionnaire measured pilots' intentions to take risks, along with the attitude towards the behaviour, subjective norms, perceived behavioural control (PBC), risk perception, and self-identity. The results showed that attitude, subjective norm, PBC, and risk perception explained 52% of the variance in behavioural intentions. Additionally, pilots' risk-taking decisions can be influenced by experience. Inexperienced pilots had a relatively stronger intention to take risks and a more favourable attitude towards risky behaviour. Moreover, pilots were more likely to rely on their own direct experience in the decision-making process.
Practitioner summary: This study examined the pilots' risk-taking intentions under adverse weather conditions using a questionnaire based on the TPB theory. Results demonstrated that the TPB model can be applied to the risk-taking scenario and that experience can influence pilots' decisions. These findings have implications for improving flight safety and lowering accident rates.
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•The effect of roughness on the brush layer has been studied for the first time.•When roughness exists, the total volume charge density is greater than ideal.•If pH is near 5.5, the ...volume charge density is little affected by roughness.
Functionalized nanoparticles and nanochannels have found widespread applications in various fields, such as biomedicine, sensing, energy, and detection, due to their unique properties and functions. Previous studies on the brush layer have typically assumed it to be a smooth surface without deformation. However, some researchers have explored the impact of particle roughness on the surface charge of nanoparticles. Drawing inspiration from their work, we establish a theoretical model of nanoparticles modified by brush layers with varying degrees of roughness based on the Poisson-Nernst-Planck equations. In this study, we investigate the change in brush layer charge density with brush layer roughness at various pH values and different solution concentrations. Our results indicate that as roughness increases, the ratio of the total volume charge density of the brush layer to that without roughness gradually decreases. While the concentration increases, the normalization of the volume charge density of the brush layer with different roughness will tend to 1.02. If the pH value is near the isoelectric point and the concentration of the salt solution is more significant, the maximum variation range of the normalization of volume charge density affected by roughness is 0.0015. Furthermore, we found that under the influence of the grafting density of the brush layer, the maximum variation range of the normalized charge density of the brush layer is 0.00432 near the isoelectric point, which indicates that the grafting density has little effect. These findings provide valuable theoretical support for the application of nano-modification technology in various fields. By understanding the impact of brush layer roughness and other factors on the behavior of functionalized nanoparticles, we can more effectively design and implement nanomaterials for a range of applications.
In this paper, we propose a control algorithm for quadruped walking robots to track the Zero Moment Point (ZMP) trajectory using Preview Control. In critical moment of trot pace, we can assume the ...robot as a linear inverted pendulum so that the linear inverted pendulum model can be applied to describe the dynamic behavior of our quadruped robot. A preview controller therefore is designed for this non-minimum phase system to get the optimal input of the system. ZMP reference trajectory can be decomposed into two parts. One is on the direction of movement, and the other is on the vertical direction of it. With the preview controller we can track the reference in both two directions and the optimal trajectory tracking can be achieved.
Nanopores have become a popular single‐molecule manipulation and detection technology. In this paper, we have constructed a continuum model of the nanopore; the arbitrary Lagrangian‐Eulerian (ALE) ...method is used to describe the motion of particles and fluid. The mathematical model couples the stress‐strain equation for the dynamics of a deformable particle, the Poisson equation for the electric field, the Navier‐Stokes equations for the flow field, and the Nernst‐Planck equations for ionic transport. Based on the model, the mechanism of field‐effect regulation of particles passing through a nanopore is investigated. The results show that the transport of particles which is controlled by the field effect depends on the electroosmotic flow (EOF) generated by the gate electrode in the nanopore and the electrostatic interaction between the nanopore and particles. That also explains the asymmetry of particle transport velocity in the nanopore with a gate electrode. When the gate potential is negative, or the gate electrode length is small, the maximum deformation of the particles is increased. The field‐effect regulation in the nanopore provides an active and compatible method for nanopore detection, and provides a convenient method for the active control of the particle deformation in the nanopore.
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