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The exchange of Marine literature is conducive to enhancing the understanding and friendship between the two peoples, and is also closely related to international political relations. However, tensions and uncertainties in international political situations often carry a risk of developing anxiety disorders.
Subjects and Methods
Based on a psychological perspective, we collected personal information about participants’ personal information, the degree of anxiety disorders and the perception of international political relationships through questionnaires. The sample includes 400 people from Both China and Japan. The correlation of anxiety disorder and international political relations was analyzed by Logistic.
The research results show that the international political relations under the background of Sino-Japanese Marine literature exchange have a significant impact on the anxiety disorders of the two peoples (P <0.05). In the tense and unstable political environments, people generally show higher levels of anxiety. In addition, compared with the Chinese people, the Japanese people are more likely to experience anxiety disorders under the pressure of international political relations.
International political relations have an important impact on people’s mental health. In order to reduce public anxiety disorders, it is necessary to strengthen communication and cooperation between China and Japan to improve people’s psychological resilience and coping ability through various channels. In addition, governments and the international community should work together to promote a stable and sustainable development of international political relations and reduce the risk of anxiety among people.
General Project of Philosophy and Social Science Research in Jiangsu Universities in 2022 (No. 2022SJYB1858); Fellowship: Project of Social Science Foundation of Jiangsu Province in 2017 (No. 17WWB006*).
To examine the associations of pregnant women’s dietary and sedentary behaviours with their children’s birth weight.
Secondary data analysis was conducted using data from a randomised controlled trial, Communicating Healthy Beginnings Advice by Telephone, conducted in Australia. Information on mothers’ socio-demographics, dietary and sedentary behaviours during pregnancy was collected by telephone survey at the third trimester. Birth weight data were extracted from the child’s health record book. Multinomial logistic regression models were built to examine the associations of pregnant women’s dietary and sedentary behaviours with children’s birth weight.
Pregnant women and their children.
A total of 1132 mother–child dyads were included in the analysis. The majority of infants (87 %, n 989) were of normal birth weight (2500 g to <4000 g), 4 % (n 50) had low birth weight (<2500 g) and 8 % (n 93) had macrosomia (≥4000 g). Mothers who ate processed meat during pregnancy were more likely to have macrosomia (adjusted risk ratio (ARR) 1·80, 95 % CI (1·12, 2·89)). The risk of macrosomia decreased as the number of dietary recommendations met by mothers increased (ARR 0·84, 95 % CI (0·71, 0·99)). Children’s birth weight was not associated with mothers’ sedentary time. Children’s low birth weight was not associated with mothers’ dietary and sedentary behaviours during pregnancy.
Maternal consumption of processed meat during pregnancy was associated with an increased risk of macrosomia. Increasing number of dietary recommendations met by mothers was associated with a lower risk of macrosomia. The findings suggested encouraging pregnancy women to meet dietary recommendation will benefit children’s birth weight.
In Beijing, the capital of China, routine measles mass vaccination has been in place for decades with high coverage; and since the 2000s, catch-up vaccination programmes have been implemented for migrant workers coming to the city. However, measles epidemics in Beijing persisted. Here, we explored the contributing factors of persistent measles transmission in Beijing using an epidemic model in conjunction with a particle filter. Model inputs included data on birth, death, migration, and vaccination. We formulated a series of hypotheses covering the impact of migrant influx, early waning of maternal immunity, and increased mixing among infants; we compared the plausibility of the hypotheses based on model fit to age-grouped, weekly measles incidence data from January 2005 to December 2014, and out-of-fit prediction during 2015–2019. Our best models showed close agreement with the data, and the out-of-fit prediction generally captured the trend of measles incidence from 2015 to 2019. We found that large influx of migrants with considerably higher susceptibility likely contributed to the persistent measles transmission in Beijing. Our findings suggest that stronger catch-up vaccination programmes for migrants may help eliminate measles transmission in Beijing.
A model-free adaptive robust control based on time delay estimation (TDE) is proposed for robot in the presence of disturbance and input saturation. TDE is utilized to estimate the complicated nonlinear terms of the robot including unknown dynamics and disturbance, and a TDE error observer is developed to estimate the inevitable TDE error. When the input torque of the robot exceeds the upper or lower limit of the input saturation, an auxiliary system and a saturation deviation boundary adaptive law are employed to mitigate the negative impact of input saturation on the position tracking. Finally, the robust control law is obtained by backstepping. The stability of the closed-loop system is proved by Lyapunov functions, and the validity of the proposed method is demonstrated by comparative simulations and experiments. Compared with the model-based controllers and other model-free controllers, the proposed method does not necessitate the accurate dynamic model of the complicated system and with lower computation. Moreover, it can guarantee the desired position tracking performance of the robot even subject to disturbance and input saturation simultaneously.
Placental trophoblastic cells play important roles in placental development and fetal health. However, the mechanism of trophoblastic cell fusion is still not entirely clear. The level of Tspan5 in the embryo culture medium was detected using enzyme-linked immunosorbent assay (ELISA). Fusion of BeWo cells was observed by immunofluorescence. Cell fusion-related factors and EMT-related factors were identified by qRT-PCR and western blotting. Notch protein repressor DAPT was used to verify the role of Tspan5 in BeWo cells. The expression of Tspan5 was significantly increased in embryo culture medium. The fusion of BeWo cells was observed after treatment with forskolin (FSK). Cell fusion-related factors (i.e. β-hCG and syncytin 1/2) and Tspan5 were significantly increased after FSK treatment. In addition, FSK treatment promoted EMT-related protein expression in BeWo cells. Knockdown of Tspan5 inhibited cell fusion and EMT-related protein levels. Notch-1 and Jagged-1 protein levels were significantly upregulated, and the EMT process was activated by overexpression of Tspan5 in FSK-treated BeWo cells. Interestingly, blocking the Notch pathway by the repressor DAPT had the opposite results. These results indicated that Tspan5 could promote the EMT process by activating the Notch pathway, thereby causing cell fusion. These findings contribute to a better understanding of trophoblast cell syncytialization and embryonic development. Tspan5 may be used as a therapeutic target for normal placental development.
Chapter 5 focuses on the CALPHAD approach and its thermodynamic basis with the crucial concept of “phase." The origins, development, and principles of the CALPHAD method are briefly explained and current software is compiled (Thermo-Calc, Pandat, FactSage, and more). Thermodynamic modeling of Gibbs energy is introduced, from simple pure substances to complex solution phases. Examples of how to establish a thermodynamic database are given, and key issues on the consistency, coherency, quality assurance, and safety of the database are emphasized. The most important application examples in the computational design of alloys and their processing are separated in two levels. In the first level, solely thermodynamic CALPHAD databases are required. It is shown which type of calculations have proved most useful to guide design. In the second level, applications using extended CALPHAD-type databases with kinetic and thermophysical material parameters are outlined for casting, solidification, and heat treatment processes. The use of advanced CALPHAD-type software packages is demonstrated. Finally, a case study on design of Al alloys with improved hot cracking resistance is presented with these tools.
Chapter 10 starts with category and production processes of cemented carbides. Subsequently, case studies for three cemented carbides are demonstrated. In the case of ultrafine cemented carbide, thermodynamic calculations were utilized to select composition and sintering temperature to avoid segregation of the (Ta,W)C phase. Optimal mechanical properties were obtained via adding VC and Cr3C2 inhibitors and the selected sintering temperature and composition. For WC–Co–Ni–Al cemented carbides, calculated phase diagrams and interfacial energy were employed to optimize the composition of Co–Ni–Al binder phase and sintering temperature. The morphology of WC was controlled through phase-field simulation and microstructure characterization. The best trade-off between transverse rupture strength and Rockwell hardness is obtained accordingly. For gradient cemented carbides, thermodynamic and diffusion calculations were performed to select composition and sintering schedule to provide microstructure parameters. A microstructure-based model was then developed to predict the hardness distribution. This simulation-driven materials design leads to development of these products within three years.
Introducing state-of-the art computational methods, this book combines detailed explanations with real-world case studies to give a full grounding in the design of engineering materials. This book presents a wide spectrum of key computational methods, such as CALPHAD-method, first-principles calculations, phase-field simulation and finite element analysis, covering the atomic-meso-macro scale range. The reader will see these methods applied to case studies for steel, light alloys, superalloys, cemented carbides, hard coating and energy materials, demonstrating in detail how real-world materials are designed. Online ancillary material includes input files for computational design software, providing the reader with hands-on design experience. Step-by-step instructions will allow you to perform and repeat the simulations discussed in the book. Aimed at both graduate and undergraduate students as well as non-specialist researchers in materials science and engineering, including ceramics, metallurgy, and chemistry, this is an ideal introductory and reference book.
In Chapter 3, we mainly focus on the fundamentals of typical mesoscale simulation methods, which can provide a bridge between atomistic structures and macroscopic properties of materials. Among many mesoscale simulation methods, the phase-field and cellular automaton methods are extremely popular and powerful for simulating microstructure evolution. Consequently, we first give a detailed introduction on the fundamentals of the two methods, briefly describing some other mesoscale simulation methods, such as level set and front tracking. After that, application examples using individual mesoscale simulation methods and integrations of the phase-field method with other simulation methods such as atomistic simulation, crystal plasticity, CALPHAD, and machine learning are described in detail. Finally, a case study for design of high-energy-density polymer nanocomposites using the phase-field method is very briefly presented.
Chapter 8 focuses on the design of important Al- and Mg-based light alloys. Selected examples show how CALPHAD simulation tools can be used to understand and predict the effect of alloying elements and processing conditions on alloy properties and how to use that in the design of alloys. For Al alloys, two case study examples using the extended CALPHAD-type databases are demonstrated. For cast alloy A356 (Al–Si,Mg), the solidification simulation involving dedicated microsegregation modeling is presented. For the wrought alloy 7xxx (Al–Zn,Mg/Cu), elaborate heat treatment simulation with precipitation kinetics is the design tool. For Mg alloy structural components, simulations of solidification path and T6 heat treatment of AZ series (Mg–AlZn) and the development of Mg–Al–Sn-based (AT) cast alloys involving also microsegregation simulation are demonstrated. Finally, the design of biomedical Mg alloy implants utilizing the CALPHAD method and the state-of-the-art bioresorbable Mg alloy stent to cure coronary artery disease is presented.
In Chapter 11, first an introduction to cutting tools is presented, followed by case studies for two hard coatings. For the TiAlN PVD coating case, we describe how to adjust the formation of metastable phase, select the deposition temperature, and manipulate microstructure to obtain desired mechanical properties through first-principles calculations and thermodynamic calculations. The deposition of the TiAlN/TiN and TiAlN/ZrN multilayer guided by first-principles calculations is also briefly mentioned. For the TiCN CVD coating, we demonstrate that computed CVD phase diagrams can accurately describe phases and their compositions under the given temperature, total pressure, and pressures of various gases. Subsequently, computational fluid dynamics (CFD) is used to provide temperature field, velocity, and distributions of various gases inside the CVD reactor. From that information, calculations-designed experiments were conducted and TiCN coatings were deposited highly efficiently. These simulation-driven designs for the hard coatings have found industrial applications in just two years, much quicker compared to the costly experimental approach.
Chapter 9 focuses on superalloys operating at high temperature where high strength as well as creep and corrosion resistance are demanded. We take Ni-based single-crystal superalloys and Ni–Fe-based superalloys for advanced ultrasupercritical (A-USC) power plants as examples to demonstrate how alloy design is accomplished in these multicomponent alloy systems. The first case study introduces the design procedure of Ni-based single-crystal superalloy by using a multicriterion constrained multistart optimization algorithm. In the second case study, the design procedure of an Ni–Fe-based superalloy with the artificial neural network (ANN) model combined with a genetic algorithm (GA) based on an experimental dataset is presented.
Chapter 6 starts with a definition of thermophysical properties, followed by detailed descriptions of important terms and equations in diffusion, including Fick’s laws on diffusion; four types of diffusion coefficients (self-diffusion, impurity diffusion, intrinsic diffusion, and interdiffusion); atomic mechanisms of diffusion; diffusion equations in binary, ternary, and multicomponent phases; as well as phases with narrow homogeneity range. Short-circuit diffusion is also briefly mentioned. Subsequently, several computational methods, including first-principles calculations, MD simulation, semi-empirical approaches, and DICTRA software, are presented to calculate or estimate diffusivity and atomic mobilities from which various diffusivities can be computed. Modeling of selected important thermophysical properties, including interfacial energy, viscosity, volume, and thermal conductivity, is briefly introduced. A procedure to establish thermophysical databases is described from a materials design point of view. A case study for simulating age hardening in AA6005 Al alloys is demonstrated mainly using thermophysical properties as input to show their importance for materials design.
Chapter 12 shows strategies to design hydrogen storage materials (example LiBH4) and Li-ion batteries (example LixMn2O4 spinel cathode) through computations. The first case shows that the dehydrogenation of LiBH4 and the role of catalysts could be understood by first-principles (FP) calculations, thermodynamic modeling, and ab initio molecular dynamics simulations. CALPHAD calculations reveal phase relations and decomposition reactions for the targeted systems. Further understanding of LiBH4 decomposition is generated by FP calculations associated with formation and migration of lattice point defects. The second case aims at understanding the performance of Li-ion batteries from a comprehensive composition-structure-property relationship. The key factors (energy density, cyclability and safety) determining the performance of the battery can be evaluated by cell voltage, capacity, electrochemical stability, extent of Jahn-Teller distortion, thermodynamic stability, and extent of oxygen gas release. All these properties are obtained by combining FP calculations with CALPHAD calculations.