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This paper studies the joint optimization problem of vessel scheduling and refueling strategy for container liner shipping with cooperative agreements signed by the container terminal operators and the shipping company with multiple vessel arrival time windows, multiple start and end times, and multiple handling rates. A non-linear mixed integer programming model for vessel scheduling and refueling strategy problem of liner shipping is established considering fuel price difference and discount factors at different refueling ports, which aims to minimize the total cost of liner shipping service. A set of discretization and linearization technique is applied to the original model in accordance with the vessel navigation controlling practice. Taking the AEX1 route served by China COSCO Shipping Corporation Limited as an example, a large number of simulation verifications are conducted. The results of numerical examples show that the joint optimization of vessel scheduling and refueling strategy helps shipping companies to flexibly adjust vessel sailing speed. It can significantly reduce the total cost of liner shipping service. The sensitivity analysis indicates that the total cost of liner shipping service and the vessel refueling volume in a voyage will reduce with the expansion of time window of vessel arrival at port in the cooperative agreement. No matter how the fuel price changes, the joint optimization of vessel scheduling and refueling strategy can effectively reduce the total cost of liner shipping service.

A stereo vision system provides important support for underwater robots to achieve autonomous navigation, obstacle avoidance, and precise operation in complex underwater environments. This article proposes an unsupervised underwater stereo matching method based on semantic attention. By combining deep learning and semantic information, it fills the challenge of insufficient training data, enhances the intelligence level of underwater robots, and promotes the progress of underwater scientific research and marine resource development. This article proposes an underwater unsupervised stereo matching method based on semantic attention, targeting the missing training supervised dataset for underwater stereo matching. An adaptive double quadtree semantic attention model for the initial estimation of semantic disparity is designed, and an unsupervised AWLED semantic loss function is proposed, which is more robust to noise and textureless regions. Through quantitative and qualitative evaluations in the underwater stereo matching dataset, it was found that D1 all decreased by 0.222, EPE decreased by 2.57, 3px error decreased by 1.53, and the runtime decreased by 7 ms. This article obtained advanced results. [ABSTRACT FROM AUTHOR]

Improving individuals' low-carbon awareness has become an important research topic. Gamification design is regarded as a potential IT solution to this social problem. Although much research is concerned with the effect of low-carbon awareness to improve individuals' behaviour, little attention has been paid to exploring how to improve low-carbon awareness, especially in the context of green gamification. To fill this research gap, our study uses the cognitive dissonance theory to build a theoretical model for exploring the impacts of green gamification factors on individuals' low-carbon awareness. The model is also used to explore the mediating role of cognitive dissonance and the moderating effect of emotional dependence. Empirical results reveal that visibility of achievement, competition, and interactivity have positive impacts on users' cognitive dissonance, which further positively affect users' low-carbon awareness. In addition, users' emotional dependence positively moderates the relationship between green gamification factors and users' cognitive dissonance. These results extend the cognitive dissonance theory and the literature on green gamification. New insights and practical implications for the designers of gamification application and environmental protection organisations are also provided in our study. [ABSTRACT FROM AUTHOR]

In this study, we report that geopolymer materials containing different amounts of graphitic carbon nitride (g‐C3N4) (C3N4/GP) can remove methylene blue (MB) using the synergistic effects of adsorption and photodegradation. A geopolymer containing 3 wt% g‐C3N4 (3 wt%C3N4/GP) had the best MB removal efficiency of 94.62% within 60 min, under visible light. The results showed that geopolymers can act as carriers for g‐C3N4, and the relative amount of adsorbent and photocatalyst influences the removal of MB. 3 wt%C3N4/GP was also used for additive manufacturing by using direct ink writing technology. In order to improve the efficiency of MB removal, a pore‐forming agent (K12) was added in the synthesis process to prepare three‐dimensional‐printed porous C3N4/GP. The results showed that the porous C3N4/GP was effective in removing MB. This work provides a simple strategy for preparing efficient and green materials for removing organic pollutants. [ABSTRACT FROM AUTHOR]

In this paper, a honeycomb Si3N4 ceramic was fabricated by 3D printing with a well‐preserved structure. The effects of Si3N4 content on the rheological properties of Si3N4/sol–silica ink and the printing resolution of products were investigated. The microstructure, phase composition, liner shrinkage rate, and fracture behavior of printed samples before and after sintering were systematically characterized in detail. The results showed that the modified inks had the optimized rheological properties, and the stress–shear rate curves corresponding to each slurry could be well described by Bingham and Herschel–Bulkley fluid models. The corresponding slump rates of the printed samples with different Si3N4 to sol–silica mass ratios were all lower than 4%, and the linear shrinkage rate of all of the samples after sintering was below 20%. The fracture behavior under compressive loading of the honeycomb Si3N4 ceramics tended to be non‐catastrophic fractures both before and after sintering. The compressive strengths of all of the printed samples decreased with the increase of the Si3N4 content, and the highest compressive strength of the honeycomb ceramics could reach 131.2 MPa after sintering at 1600°C, which was about 366.9% higher than that of the samples in green state prior to the sintering. [ABSTRACT FROM AUTHOR]

Pollucite has been proposed as an ideal candidate material for addressing the critical challenge of the safe trapping of the 137Cs radionuclide. However, its detailed corrosion mechanism remains elusive. In this work, we performed reactive and ab initio molecular simulations to explore the leaching behavior of Cs+ from pollucite glass–ceramics at the initial stage. The nonbridging oxygen ions on the surface are protonated at first, followed by the release of Cs+ associated with these oxygen ions. For the glass phase, the inner Cs+ could leach out due to the interaction with water molecules, whereas only the Cs+ present at the surface leach out for pollucite, confirming its remarkable chemical stability. The hydrolysis of Si/Al–O bonds in pollucite is thermodynamically unfavorable, and Al–O bonds are the weak spots. Moreover, the migration barriers of Cs+ in pollucite were calculated by the climbing image nudged elastic band method, and the high barriers reveal that pollucite immobilizes Cs+ stably. This study paves the way for predicting the long‐term safety of a nuclear waste immobilization repository. [ABSTRACT FROM AUTHOR]

Traditional geopolymer structures benefit from the durability, irradiation resistance, and environmental friendliness, but their brittleness limits their applications where repeated, impactive strains are imparted. This situation may be alleviated if complex structures with tunable geometry can be fabricated, for example, through 3D printing based on direct ink writing (DIW). In this research, SiC whisker/geopolymer (SiCw/GP) composites were fabricated by the DIW for the first time. The rheological behaviors of the SiCw/GP inks and the fracture behaviors of the printed samples were explored. The modified printing inks exhibited non‐Newtonian fluid behavior (shear‐thinning). Subsequently, a series of lightweight architected structures were fabricated, and they revealed how reinforcement and architecture of the printed structures could influence both the strength and toughness of the SiCw/GP composites. [ABSTRACT FROM AUTHOR]

Hepatitis B virus (HBV), a common blood transmission pathogen worldwide, can lead to viral hepatitis, cirrhosis, liver cancer, and other liver diseases. In particular, occult hepatitis B virus infection (OBI) may be caused by an immune response leading to suppressed virus replication. Gut microbiota can change the immunity status of the human body and, therefore, affect the replication of HBV. Thus, to identify whether there are differences in gut microbiota between HBV carriers and OBI carriers, we collected fecal samples from 18 HBV carriers, 24 OBI blood donors, and also 20 healthy blood donors as negative control. After 16S sequencing, we found that the abundance of Faecalibacterium was significantly reduced in samples from OBI blood donors compared with those from healthy blood donors. Compared with samples from HBV carriers, the samples from OBI blood donors had a significantly increased abundance of Subdoligranulum , which might stimulate immune activation, thus inhibiting HBV replication and contributing to the formation of occult infection. Our findings revealed the potential role of gut microbiota in the formation of OBI and further provided a novel strategy for the treatment of HBV infection.IMPORTANCEOccult hepatitis B virus infection (OBI) is a special form of hepatitis B virus infection with hepatitis B surface antigen (HBsAg) positive and hepatitis B virus (HBV) DNA negative. Gut microbiota may contribute to the immune response leading to suppressed virus replication and, thus, participates in the development of OBI. The study on gut microbiota of OBI blood donors provides novel data considerably advancing our understanding of the immune mechanism for the determination of occult hepatitis B virus infection, which is helpful for improving the strategy of the treatment of HBV infection., Competing Interests: The authors declare no conflict of interest.

Introduction: The coronavirus disease 2019 (COVID-19) pandemic has created lots of difficulties for individuals to seek medical help offline. Telehealth is considered as a potential approach to solve this issue. During the COVID-19 pandemic, although the use of telehealth has increased in the short term, it still remains unknown whether the use of telehealth can maintain a high level of development in the long term. The purpose of this article is to investigate the impact of COVID-19 pandemic on telehealth use across time and regional medical resources. Materials and Methods: Our research used the Internet search index from Baidu Index Platform in 31 provinces of China as the proxy of telehealth use. A total of 2,119,486 times of searching behaviors from January 2018 to December 2021 are included in our dataset. Changing plots, the method of analysis of variance and empirical models are applied to reveal the relationship between COVID-19 pandemic and telehealth use. Results: Baidu Index counts increased ( p < 0.01) at the beginning of COVID-19 pandemic (2020) but started to decline ( p < 0.01) during the period of regular epidemic prevention and control (2021). Moreover, the counts of Baidu Index in regions with rich medical resources are higher than those in other regions in 2020. Comparing Baidu Index counts in 2020, the COVID-19 pandemic has higher positive effects on telehealth use during the period of 2021 in regions with average and poor medical resources. Conclusions: COVID-19 pandemic has a positive effect on telehealth use in 2020 but has a negative effect in 2021. During the epidemic, telehealth use differs in regions with rich, average, and poor medical resources. Our findings indicate that the use of telehealth should be promoted with different measures in regions with different medical resources, thereby contributing its healthy development in the long term.