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Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: Postoperative delirium (POD) commonly occurs after major abdominal surgery and is associated with increased morbidity and mortality. There have been many studies on the relationship between POD and various surgeries, but research on POD after pancreatic cancer surgery is limited. The aim of this study was to identify the incidence and risk factors of POD after pancreatic cancer surgery. Methods: The subjects of this retrospective analysis were 196 patients who were transferred for postoperative care after pancreatic cancer surgery, to a 12-bed critical care medicine ward at Shandong Provincial Hospital, affiliated with Shandong First Medical University, between January 2015 and December 2019. The patients were divided according to whether they suffered POD into a delirium group and a non-delirium group. Delirium was assessed using the Confusion Assessment Method for the Intensive Care Unit and two independent medical practitioners analyzed all the data. Univariate and multiple logistic regression analyses were performed. Results: The overall delirium incidence was 20.41%, which increased to 29.03% for patients aged ≥ 70 years. POD was associated with age, smoking, the American Society of Anesthesiologists classification, the Acute Physiology and Chronic Health Evaluation II score, and the TNM stage of the cancer. The variables concerning sex, drinking, hypertension, a history of cerebral disease, surgery type, operation time, amount of bleeding, and the intraoperative use of dexmedetomidine did not differ significantly between the two groups. There was no significant difference in the length of ICU stay, with the exclusion of long-term stay for complications, between the groups, but POD tended to prolong the postoperative hospital stay and increase the risk of mortality. There was also a gradual decline in the incidence of POD between 2015 and 2019, especially from 2015 to 2018, after preventive measures were implemented. Conclusion: POD is related to many risk factors and worthy of attention. Appropriate management can reduce its incidence or at least shorten its duration. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effect of a constant current (CC) power supply on the CC ocean observation system is a problem that once was neglected. The dynamic characteristics of the CC power supply may have great influence on the whole system, especially the voltage behavior in the event of load change. This needs to be examined. In this paper, a method is introduced to check whether the CC power supply can satisfy the dynamic requirements of the CC ocean observation system. An equivalent model to describe the non-ideal CC power supply is presented, through which the dynamic characteristics can be standardized. To verify the feasibility of this model, a minimum system of a single node in the CC ocean observation system is constructed, from which the model is derived. Focusing on the power failure problem, the output voltage responses are performed and the models are validated. Through the model, the dynamic behavior of the CC power supply is checked in a practical design. [ABSTRACT FROM AUTHOR]

Constant current power transmission is considered a good choice for subsea observatories due to its high resistance to shunt faults. A constant current subsea observatory is planned to be constructed in the East China Sea. We discuss a constant current subsea observatory system used for scientific experiments. The power system and its heat dissipation system are carefully designed. The power conversion method is challenging due to the use of constant current power, which is considerably different from traditional power systems. Thus, we adopt power compensation circuits in the conversion system to obtain a constant 48-V output for science users. A power management system that performs overvoltage protection and real-time monitoring and control of junction box is discussed. An innovative heat dissipation structure of a junction box is designed in consideration of a sealed working environment to extend the useful life of the junction box. Simulations and experiments reveal that the system has high efficiency and stability, especially in long-term applications. [ABSTRACT FROM AUTHOR]

Cabled seafloor observatories play an important role in ocean exploration for its long-term, real-time, and in-situ observation characteristics. In establishing a permanent, reliable, and robust seafloor observatory, a highly reliable cable switching and fault isolation method is essential. After reviewing the advantages and disadvantages of existing switching methods, we propose a novel active switching method for network configuration. Without additional communication path requirements, the switching method provides a way to communicate with a shore station through an existing power transmission path. A coded voltage signal with a distinct sequence is employed as the communication medium to transmit commands. The analysis of the maximum bit frequency of the voltage signals guarantees the accuracy of command recognition. A prototype based on the switching method is built and tested in a laboratory environment, which validated the functionality and reliability of the method. [ABSTRACT FROM AUTHOR]

Hybrid materials of CoFeO nanoparticles anchored on graphene prepared by a facile hydrothermal process was developed to be anode material for sodium-ion battery. The hybrid nano-structure of CoFeO/graphene not only could be useful to buffer electrode volume accompanying with Na insertion-extraction, but also could be beneficial to improve electrode electric conductivity and further keep graphene sheet separated to improve ion diffusion rate. Electrochemical measurements showed that the hybrid material anode displayed an excellent performance with a large reversible capacity of 330 mAh g after 75 cycle times and a satisfactory rate capability of 170 mAh g at 1 A g. [ABSTRACT FROM AUTHOR]

A semiclassical study of intrinsic localized spin-wave modes in a one-dimensional quantum ferromagnetic XXZ chain in an oblique magnetic field is presented in this paper. We quantize the model Hamiltonian by introducing the Dyson-Maleev transformation, and adopt the coherent state representation as the basic representation of the system. By means of the method of multiple scales combined with a quasidiscreteness approximation, the equation of motion for the coherent-state amplitude can be reduced to the standard nonlinear Schrödinger equation. It is found that, at the center of the Brillouin zone, when θ < θ a bright intrinsic localized spin-wave mode appears below the bottom of the magnon frequency band and when θ > θ a dark intrinsic localized spin-wave resonance mode can occur above the bottom of the magnon frequency band. In other words, the switch between the bright and dark intrinsic localized spin-wave modes can be controlled via varying the angle of the magnetic field. This result has potential applications in quantum information storage. In addition, we find that, at the boundary of the Brillouin zone, the system can only produce a dark intrinsic localized spin-wave mode, whose eigenfrequency is above the upper of the magnon frequency band. [ABSTRACT FROM AUTHOR]

A power monitoring and protection system based on an embedded processor was designed for the junction boxes (JBs) of an experimental seafloor observatory network in China. The system exhibits high reliability, fast response, and high real-time performance. A two-step power management method which uses metal-oxide-semiconductor field-effect transistors (MOSFETs) and a mechanical contactor in series was adopted to generate a reliable power switch, to limit surge currents and to facilitate automatic protection. Grounding fault diagnosis and environmental monitoring were conducted by designing a grounding fault detection circuit and by using selected sensors, respectively. The data collected from the JBs must be time-stamped for analysis and for correlation with other events and data. A highly precise system time, which is necessary for synchronizing the times within and across nodes, was generated through the IEEE 1588 (precision clock synchronization protocol for networked measurement and control systems) time synchronization method. In this method, time packets were exchanged between the grandmaster clock at the shore station and the slave clock module of the system. All the sections were verified individually in the laboratory prior to a sea trial. Finally, a subsystem for power monitoring and protection was integrated into the complete node system, installed in a frame, and deployed in the South China Sea. Results of the laboratory and sea trial experiments demonstrated that the developed system was effective, stable, reliable, and suitable for continuous deep-sea operation. [ABSTRACT FROM AUTHOR]

Nanosize N-doped graphene is prepared from N-containing carbon nanotubes (CNTs) by chemical exfoliation. The CNTs adopted for graphene are characterized by a discontinuous wall that consists of nanosize graphite layers, exhibiting a bamboo-like appearance. Take advantage of this characterization, the most time-consuming process of chemical oxidation that involves intercalation in graphene from CNT has been markedly reduced. The reduction in processing time is attributed to the diffusion distance of chemical oxidation intercalation into nanosize graphite composed of a bamboo-like carbon nanotube (BCNT) wall being far less than that of conventional chemical exfoliation into microsize graphite. The as-prepared nanosize N-doped graphene from BCNTs has shown an excellent electrochemical performance for Li-ion battery and Na-ion battery anode materials. [ABSTRACT FROM AUTHOR]

In this paper, we present an analytical study on intrinsic localized spin-wave modes in antiferromagnetic chains with Dzyaloshinsky-Moriya interaction in semiclassical limit. By means of the method of multiple scales combined with a quasi-discreteness approximation, the nonlinear Schrödinger equation is derived for the conherent-state amplitude. It is found that a bright stationary intrinsic localized spin-wave mode can appear below the linear spin-wave spectrum. Besides, we show that the antiferromagnetic chain can produce a dark intrinsic localized spin-wave mode, namely, nonpropagating kink, which is a typical nonlinear resonant mode. [ABSTRACT FROM AUTHOR]

In this study, gelatin was extracted from bighead carp (Hypophthalmichthys nobilis) scales by water bath (WB) and ultrasound bath (UB) at 60 °C for 1 h, 3 h and 5 h, named WB1, WB3, WB5, UB1, UB3 and UB5, respectively. The physicochemical properties of gelatin were investigated. The result indicated that gelatin extracted from bighead carp scales had a high protein content (84.15 ~ 91.85 %) with moisture (7.11 ~ 13.65 %), low ash content (0.31 ~ 0.97 %). All extracted gelatin contained α-and β-chains as the predominant components. Gelatin extracted by UB obtained much higher yield (30.94-46.67 %) than that of WB (19.15-36.39 %). More voids and less sheets of gelatin structure were observed, when the gelatin was extracted by UB for longer time. Gelatin of UB-assisted extraction normally exhibited lower gel strength and melting points than that of WB, which may be resulted from the protein degradation reflected by the FTIR spectra and higher free amino group content. However, there was no significant difference between WB1 and UB1. Therefore, the ultrasound assisted extraction in a short time was a promising method to enhance the yield and obtain gelatin with high quality. [ABSTRACT FROM AUTHOR]

By using a full quantum approach based on the time-dependent Hartree approximation and the semidiscrete multiple-scale method, we study quantum nonlinear excitations in a one-dimensional ferromagnetic chain with octupole-dipole interaction and on-site uniaxial anisotropy. We find that quantum solitons and breathers can exist in the ferromagnetic chain, and analyze existence conditions of these excitations. Since the system states corresponding to quantum breathers are stationary states, we can get the energy level formula of such quantum breathers. [ABSTRACT FROM AUTHOR]

We develop a new kind of underwater inductive coupling power transfer (ICPT) system to evaluate wireless power transfer in autonomous underwater vehicle (AUV) docking applications. Parameters that determine the performance of the system are systematically analyzed through mathematical methods. A circuit simulation model and a finite element analysis (FEA) simulation model are developed to study the power losses of the system, including copper loss in coils, semiconductor loss in circuits, and eddy current loss in transmission media. The characteristics of the power losses can provide guidelines to improve the efficiency of ICPT systems. Calculation results and simulation results are validated by relevant experiments of the prototype system. The output power of the prototype system is up to 45 W and the efficiency is up to 0.84. The preliminary results indicate that the efficiency will increase as the transmission power is raised by increasing the input voltage. When the output power reaches 500 W, the efficiency is expected to exceed 0.94. The efficiency can be further improved by choosing proper semiconductors and coils. The analysis methods prove effective in predicting the performance of similar ICPT systems and should be useful in designing new systems. [ABSTRACT FROM AUTHOR]

Based on the Hartree approximation and the semidiscrete multiple-scale method, quantum breathers in an anisotropic ferromagnetic Heisenberg chain with biquadratic exchange interaction are predicted analytically. The existence condition of quantum breathers is obtained, and the properties of quantum breathers are analyzed. Moreover, it is shown that the energy of such quantum breathers is quantized. [ABSTRACT FROM AUTHOR]

An IEEE 1588 based application scheme was proposed to achieve accurate time synchronization for a deep seafloor observatory network based on the communication topological structure of the Zhejiang University Experimental and Research Observatory. The principles of the network time protocol (NTP) and precision time protocol (PTP) were analyzed. The framework for time synchronization of the shore station, undersea junction box layer, and submarine science instrument layer was designed. NTP and PTP network signals were decoded by a PTP master clock on a shore station that receives signals from the Global Positioning System and the BeiDou Navigation Satellite System as reference time sources. These signals were remotely transmitted by a subsea optical-electrical composite cable through an Ethernet passive optical network. Accurate time was determined by time synchronization devices in each layer. Synchronization monitoring experiments performed within a laboratory environment indicated that the proposed system is valid and has the potential to realize microsecond accuracy to satisfy the time synchronization requirements of a high-precision seafloor observatory network. [ABSTRACT FROM AUTHOR]

Due to the shortage of suitable research methods for real-time and long-term observation of oceans, an innovative approach that can provide abundant power and wide bandwidth is being developed worldwide for undersea instruments. In this paper, we develop a direct current (DC) power system which is applied to a multi-node cabled ocean observatory system named ZERO (Zhejiang University Experimental and Research Observatory). The system addresses significant issues ranging from terrestrial facility to subsea infrastructure, and focuses on using appropriate methods to deal with several key challenges, including delivery, conversion, distribution, and management of power, and heat dissipation in pressure vessels. A basic laboratory platform consisting of a shore station, a primary node in a water tank, and a secondary node in a deep-sea simulation chamber under 42 MPa pressure was built and fully tested. An improved secondary node was deployed in Monterey Bay in California for a deep-sea trial. An 11-day laboratory test and a half-year sea trial proved that the DC power system based on our proposed methods is viable for the underwater multi-node observatory system. [ABSTRACT FROM AUTHOR]

In underwater applications of contactless power transmission (CLPT) systems, high pressure and noncoaxial operations will change the parameters of electromagnetic (EM) couplers. As a result, the system will divert from its optimum performance. Using a reluctance modeling method, we investigated the gap effects on the EM coupler in deep-sea environment. Calculations and measurements were performed to analyze the influence of high pressure and noncoaxial alignments on the coupler. It was shown that it is useful to set a relatively large gap between cores to reduce the influence of pressure. Experiments were carried out to verify the transferring capacity of the designed coupler and system for a fixed frequency. The results showed that an EM coupler with a large gap can serve a stable and efficient power transmission for the CLPT system. The designed system can transfer more than 400 W electrical power with a 2-mm gap in the EM coupler, and the efficiency was up to 90% coaxially and 87% non-coaxially in 40 MPa salt water. Finally, a mechanical layout of a 400 W EM coupler for the underwater application in 4000-m deep sea was proposed. [ABSTRACT FROM AUTHOR]

Coating properties and performance can be tailor-designed by proper control of nano structure andprocess conditions. This paper presents two examples: first, the synthesis and optimization of 1 nm thick nitrogenated carbon (CNx) nano-layers as protective overcoats in extremely highdensity harddisksystems, and, second, the development of multilayer coatings for wear protection at elevated temperatures. Synthesis of these coatings was done by magnetron sputtering. These studies demonstrate that one canproduce atomically smooth 1 nmthickCNxovercoatswith acceptable corrosionperformance. In addition, this paper shows that, with the proper choice of nanolayer thickness and process conditions, superhard coatings based on TiN/SiNx and TiB2/TiC multilayers with high thermal stability, low internal stress, and high wear resistance can be synthesized. [ABSTRACT FROM AUTHOR]

Low hydrophilicity of graphene is one of the major obstacles for biomaterials application. To create some hydrophilic groups on graphene is addressed this issue. Herein, COOH+ ion implantation modified graphene (COOH+/graphene) and COOH functionalized graphene were designed by physical ion implantation and chemical methods, respectively. The structure and surface properties of COOH+/graphene and COOH functionalized graphene were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and contact angle measurement. Compared with graphene, COOH+/graphene and COOH functionalized graphene revealed improvement of cytocompatibility, including in vitro cell viability and morphology. More importantly, COOH+/graphene exhibited better improvement effects than functionalized graphene. For instance, COOH+/graphene with 1 × 1018 ions/cm2 showed the best cell-viability, proliferation and stretching. This study demonstrated that ion implantation can better improve the cytocompatibility of the graphene. [ABSTRACT FROM AUTHOR]