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Pancreatic neuroendocrine neoplasm (PNEN) is the second most common malignant tumor of the pancreas. It has the characteristic of high metastases rate, and the liver is the most common site for metastasis. Metastasis affects prognosis and survival seriously. A number of earlier studies have shown that the interventional therapy via hepatic artery could reduce hepatic tumor burden and hormone secretion safely and rapidly, significantly improve objective response rate (ORR), and enhance the efficacy and prolong the survival time when combined with system therapy. The interventional therapy via hepatic artery plays an important role in the treatment of PNEN liver metastases. Interventional therapy via hepatic artery could possibly increase ORR, prolong progression-free survival, and even overall survival for appropriate patients.

The bearings in a shafting system are important paths for the lateral vibration of the shaft to transmit to the hull structure and induce underwater sound. An auxiliary active magnetic bearing for suppressing the lateral vibration at the stern support of a shafting system is investigated. The active magnetic bearing situated close to the stern bearing generates electromagnetic forces to support the shaft, which decreases the contact stiffness as well as the friction between the shaft and the stern bearing and accordingly reduces the stern support acceleration. A dynamic model is established using the Timoshenko beam theory and Hamilton’s principle and the performance of the active magnetic bearing in vibration suppression of the shafting system is evaluated with position control. An experimental system is also built to verify the effectiveness of the active magnetic bearing. Numerical and experimental results have shown that the active magnetic bearing is able to suppress the stern support acceleration responses after the shaft is suspended by the active magnetic bearing. Moreover, the orbit of the shaft center is controlled as well.

Active vibration control of a shaft bracket-plate coupled system is investigated. The vibration of the plate is controlled with electromagnetic vibration absorbers (EVAs), which are mounted around the feet of the shaft bracket to impede the transmission of vibration from the bracket apex to the plate. A dynamic model is established on the Timoshenko beam theory and the Kirchhoff thin plate theory to reveal the mechanism of vibration transmission. It is exhibited that all the induced forces and moments at the coupling points contribute much to the transverse responses of the plate. The feasibility of active control with the EVAs is evaluated numerically based on the controllability of the plate vibration. It is demonstrated that the two-point in-plane control is able to attenuate the plate vibration under the excitation of in-plane disturbance forces, while the multi-point control is effective in reducing the plate vibration regardless of the directions of disturbance forces. An experimental system is built to verify the performance of the two-point in-plane control. The results have shown that with the help of adaptive control, the two-point in-plane control is capable of suppressing the vibration of the foundation induced by the in-plane forces acting on the shaft bracket.

The axial vibration of a shaft-bearing system induced by the thrust excitation is usually composed of multiple tones. To suppress the axial vibration of the shaft-bearing system, two inertial electro-magnetic actuators are mounted symmetrically at the thrust bearing and work in parallel to exert control forces. The control signal is generated by an adaptive algorithm with subband filtering, which aims to attenuate over a broadband the vibration of the thrust bearing and its foundation induced by the dynamic thrust force. To reduce computational complexity, the recursive computation is partly realized with the auto-regressive moving average (ARMA) model. The proposed active control approach is evaluated numerically at first with the dynamic model of the shaft-bearing system and then verified with an experimental system. It is demonstrated by the numerical and experimental results that the active control approach is able to suppress the multi-tone vibration of the thrust bearing and the foundation. Moreover, in comparison to the single-band adaptive feedback algorithm, the adaptive algorithm with subband filtering is more effective when the disturbance contains multiple tones.

The Industrial Control System (ICS) has become the key concept in the modern industrial world, enabling process monitoring and system control for general industrial systems and critical infrastructures. High-skilled hackers can invade an imperfect ICS by existing vulnerabilities without much effort. Conventional defenses (such as encryption and firewall) to keep invaders away are getting less and less effective when an attack is carried out by exploiting an array of particular vulnerabilities. Under this circumstance, a new-type intrusion detection system (IDS) based on deception strategy using honeypot technique is proposed, which is of dramatic effectiveness in protecting ICSs of critical infrastructures. In this honeypot-based model, we capture malicious Internet flows and system operations. We analyze the collected data before alerting and preventing the intrusion alike when it affects the system in the future. This paper deals with the model's concept, architecture, deployment, and what else can be achieved in the field of Critical Infrastructure Cybersecurity (CIC).

BackgroundWith the increase in social pressure, the anxiety symptoms of college students with mental disorders are increasing year by year. This has harmed their living standards and learning outcomes. The current intervention measures largely overlook the impact of ideological and political education in universities.Subjects and MethodsThe study used a randomized controlled trial design. The experimental group (n=60) adopted innovative ideological and political education interventions, including group discussions, role-playing, and theme reports, with an intervention period of 12 months. The control group (n=60) received routine psychological counseling services. All participants were evaluated at the beginning, duration of 6 months, and end of the study. The Hamilton Anxiety Scale (HAM-A) was mainly used for evaluation. Descriptive and inferential statistical analysis was conducted on the data using SPSS 22.0.ResultsAfter the intervention, compared with the control group, the anxiety symptoms of the experimental group of college students were significantly reduced. After 12 months of intervention, the HAM-A score of the experimental group decreased by an average of 12.1 points, while the average decrease in the HAM-A score of the control group was 3.2 points. The follow-up evaluation also confirmed this result.ConclusionsThis study shows that innovative ideological and political education interventions are significantly superior to conventional psychological counseling services, and effectively reduce anxiety symptoms of college students with mental disorders in clinical practice.AcknowledgementThe 2020 Hubei Skilled Talent Training and Research Center Project (No. 20BJN014); 2020 China University Industry, University and Research Innovation Fund - New Generation Information Technology Innovation Project (No. 2020ITA02052).

Most heritage buildings and monuments are constructed out of natural stones which suffer irrevocable degradation when undergoing wet weathering, bowing, and dissolution in outdoor conditions. Self-cleaning treatments are effective for stone protecting. Herein, nano-materials which provide enhanced protectants for Marble, Qingshi and Hedishi were prepared. Inherent microscale interstices and holes exist on polished natural stone surfaces. When treated by a commercial protectant, 101S, the surfaces were hydrophobic but not self-cleaning. Colloidal protectants were prepared by dispersion of Al2O3and SiO2nano-powder in 101S, respectively. Self-cleaning stone surfaces were achieved after treated by the protectants, meanwhile, the interstices and holes were reserved as much as possible. The principle of the as- prepared protectants is penetrating and crosslinking on the stone surfaces as well as the inner surfaces of the interstices and holes. The reserving of the micro interstices and holes is important since the breathability of the stones is remained. The self-cleaning surfaces showed good thermal stability below 250 °C. Meanwhile, changes of color and gloss of the treated stone surfaces are in the acceptable range.

X-ray photoelectron spectroscopy (XPS) and atomic force microscopy have been used to study Co nanoparticles evaporated onto freshly cleaved highly oriented pyrolytic graphite (HOPG) surfaces. XPS chemical characterization employed symmetrical line shapes and was carried out as functions of the amount of Co deposited and of the time subsequent to deposition. The nominal amounts of evaporated Co ranged from 0.5 to 175 Å. On analyzing the relationships among the Co2p, C1s, and O1s spectra, we found that evaporated Co reacts not only with HOPG surface defects (including oxidized carbon contaminant groups), but also with residual C- and O-containing species present in the vacuum chamber. Both carbide and oxide are produced as surface layers around each nanoparticle, stabilizing them and preventing further coalescence.

The X-ray photoelectron spectroscopic characterizations of Pt nanoparticles evaporated onto untreated and Ar-treated highly oriented pyrolytic graphite surfaces, with, respectively, low and high surface defect densities have been studied using multicomponent analysis with symmetric line shapes:? each Pt4f spectral component (f72and f52) was deconvoluted into three symmetric peaks. On analyzing the relationships among the Pt4f, C1s, and O1s spectra, we attribute these peaks to the existence of surface oxidation on the platinum nanoparticles and to the different electronic configurations of surface and bulk Pt atoms. We use the varying intensities of these component peaks, as a function of deposited Pt, to explain the changing shape of the Pt4f asymmetric envelope with nanoparticle size.

A rapid, simple and highly sensitive voltammetric method was developed for the determination of hydrazine based on the electrochemical oxidation of hydrazine catalyzed by TEMPOL at a glassy carbon electrode at neutral medium. A linear calibration plot was obtained over the range of 1 × 10−6M‐5 × 10−4M. The detection limit was 1 × 10−6M. The method was applied successfully to the determination of hydrazine in waste and river water.