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Warming weather has led to melting sea ice, and increasingly complex global geopolitics has drawn more countries' attention to the Arctic. The Arctic Northeast Passage, as an emerging route connecting Eurasia, has seen a sharp increase in vessel activity. The period from 2015 to 2020, being a stable and undisturbed data period, is of significant theoretical importance for exploring the natural development of the Arctic Northeast Passage. The study found that the research period can be divided into three stages: from 2015 to 2017, the number of vessels grew slowly. In 2018 and 2019, the number of vessels and vessel activities saw significant growth, but an unexpected reverse growth occurred in 2020. Different types of vessels have unique activity characteristics and evolutionary patterns, influenced by the Arctic's unique geographical environment, abundant natural resources, deepening Sino-Russian cooperation, and increasing global trade supply and demand. The results of this study aim to provide policymakers with analysis based on the initial development stage of the route, offering data support for future policy formulation, route planning, and research on the navigation safety of vessels on the Arctic Northeast Passage. [ABSTRACT FROM AUTHOR]

Marine transportation is pivotal in the rapid development of global trade, significantly enhancing international economic and trade connectivity and impacting the sustainable development of the global economy. In this study, we developed a novel technical framework based on the Laplacian matrix to evaluate the node significance and edge connectivity of the global shipping network using 2019 vessel schedule data from the top 30 liner shipping companies, as ranked by Alphaliner. Our analyses were conducted in both L-space, characterizing the connectivity function, and P-space, characterizing the transfer function. The findings indicate the following. (1) There is no consistent relationship between node significance and centrality for most ports. Ports with high node significance are mainly located in the Asia–Pacific region, with Singapore Port being the port with the highest node significance in L-space and Shanghai Port being the port with the highest node significance in P-space. (2) In L-space, the structures with significant improvements in edge connectivity in the shipping network have at least one port node that exhibits both low degree centrality and low betweenness centrality; these are primarily found on East African routes. (3) In P-space, the structures with significant improvements in edge connectivity in the shipping network are more complex but are notably linked to the ports of Assaluyeh and Bandar Abbas in Iran. The proposed node evaluation and edge addition strategy effectively analyze port significance and edge connectivity, providing decision-making support for optimizing port layouts, supporting container route planning, and enhancing the overall performance of the shipping network. [ABSTRACT FROM AUTHOR]

Compared to the traditional wet-mate underwater power supply method, Magnetic Coupling Resonant Wireless Power Transfer (MCR-WPT) technology boasts advantages such as excellent insulation, high safety, and convenient operation, showing promising application prospects in the field of power supply for underwater vehicles and other mobile underwater devices. In order to explore the transmission characteristics of this technology underwater, this article first establishes a traditional mathematical model, and then modifies the underwater model through analysis of changes in coil self-inductance and mutual inductance, as well as the impact of eddy current losses. Using the modified mathematical model of the underwater MCR-WPT system, the transmission characteristics are analyzed, and simulations and experimental validations are performed using MATLAB R2022a software. In the study of frequency characteristics, it is found that the system operates optimally when both ends of the circuit work at the resonant state; that is, when finput = fresonance = 100 kHz, the output performance is at its best, and the optimal resonant frequency significantly improves power and transmission efficiency. When the input frequency is less than 87.3 kHz or greater than 122.9 kHz, the output power decreases to less than half of the maximum power. In the investigation of load effects, the optimal load for maximizing system output power was identified, but the load that maximizes transmission efficiency is different from this optimal load. This study provides strong theoretical support and guidance for improving the performance of underwater wireless power transmission systems. [ABSTRACT FROM AUTHOR]

Magnetically coupled resonant wireless power transfer (MCR-WPT) technology offers longer effective transmission distances and higher efficiency compared to traditional charging methods, making it better suited to the prolonged and efficient operation of autonomous underwater vehicles. This paper first establishes a traditional mathematical model and then refines it while analyzing the variations in the self-inductance and mutual inductance of underwater coils. To further enhance the system's performance, a multi-objective optimization of the coupling mechanism is conducted. An orthogonal experiment is employed to determine the effects of various influencing factors on the coils' self-inductance and mutual inductance. Subsequently, an RBF neural network is used to create a regression prediction model based on the results of the orthogonal experiment. The NSGA-II algorithm is then applied for the multi-objective optimization of the coupling mechanism, resulting in a Pareto front solution set. The optimized efficiency is 93.35%, representing an approximately 6% improvement over the original system, with the power density increasing from 1.267 × 10 6   W / m 3 before optimization to 4.782 × 10 6   W / m 3 after optimization. Significant enhancement in system performance is achieved. [ABSTRACT FROM AUTHOR]

This study considers a two-tier supply chain consisting of a fairness-neutral manufacturer and a fairness-concerned retailer. The manufacturer adjusts product quality and distributes the products through the retailer. The retailer sells the products to consumers having reference quality (RQ) effects that depend on the previously purchased product quality and change over time, and is assumed to have three, i.e., fairness neutral (FN), fairness-concerned with the status reference point (FSP) and fairness-concerned with the non-status reference point (FNSP), behaviors. The supply chain is modeled as a Stackelberg game wherein the manufacturer has the first mover advantage. The utility optimal control models with fairness concerns (FC) and RQ effects under FN, FSR and FNSR are developed using prospect theory, and are reformulated using the Hamilton-Jacobi-Bellman equations as tractable forms to derive the dynamic pricing and quality decisions. The results show that pricing and quality decisions are influenced by the FN, FSR and FNSR behaviors over time. The steady-state quality and wholesale price are, but the steady-state retail price is not, influenced by the fairness reference profit and the RQ. The manufacturer should cede some profit to the retailer with FC, especially when the retailer has the bargaining power. The FC is not always beneficial to the retailer. Numerical experiments are performed to examine the effects of the major parameters on the manufacturer and retailer utilities and to derive the managerial implications [ABSTRACT FROM AUTHOR]

Simple Summary: Ruminal microbiota plays an important role in the health and milk production of dairy cows. In this study, we found that high-concentrate diet (concentrate: forage = 60:40) feeding altered the composition of the microbiota in the rumen and produced toxic metabolites (LPS and histamine). The elevated concentrations of LPS and histamine in the gut were transferred into the bloodstream and caused damage to the ruminal and cecal walls. LPS and histamine stimulated an inflammatory response in the liver with the increased presence of H1 receptors. Our study provides a basis for exploring the impact of changes in gut microbiota composition on animal health and offers a novel therapeutic strategy for treating metabolic disorders caused by SARA. The ecosystem of ruminal microbiota profoundly affects the health and milk production of dairy cows. High-concentrate diets are widely used in dairy farms and evoke a series of metabolic disorders. Several studies have reported the effects of high-concentrate diets on the ruminal microbiome, while the effect of changes in ruminal microbial flora, induced by high-concentrate diet feeding, on the liver of dairy cows has not been studied before. In this study, 12 mid-lactating Holstein Friesian cows (weight of 455 ± 28 kg; parities of 2.5 ± 0.5; starting milk yield of 31.59 ± 3.2 kg/d; DMI of 21.7 ± 1.1 kg/d; and a DIM at the start of the experiment of 135 ± 28 d) were fitted with ruminal fistulas, as well as with portal and hepatic vein catheters. All cows were randomly divided into 2 groups; then, they fed with low-concentrate diets (LC, concentrate: forage = 40:60) and high-concentrate diets (HC, concentrate: forage = 60:40) for 18 weeks. The forage sources were corn silage and alfalfa hay. After the cows of two groups were euthanized over two consecutive days, ruminal microbiota; the concentration of LPS in the rumen content; cecum content; the levels of blood and histamine in rumen fluid, blood, and the liver; the histopathological status of the rumen and cecum; and the inflammatory response of the liver were assessed in dairy cows under conditions of subacute ruminal acidosis (SARA). These conditions were caused by high-concentrate diet feeding. All data were analyzed using the independent t-test in SPSS. The results showed that high-concentrate diet feeding increased the concentration of LPS and histamine in the rumen and plasma of veins (p < 0.05). The abundance of Bacteroidetes at the phylum level, and of both Bacteroidetes and Saccharibacteria at the genus level, was decreased, while the abundance of Firmicutes at the phylum level and Oscillibacter at the genus level was increased by high-concentrate diet feeding. The decreased pH values of ruminal contents (LC = 6.02, HC = 5.90, p < 0.05) and the increased level of LPS in the rumen (LC = 4.921 × 105, HC = 7.855 × 105 EU/mL, p < 0.05) and cecum (LC = 11.960 × 105, HC = 13.115 × 105 EU/mL, p < 0.01) induced the histopathological destruction of the rumen and cecum, combined with the increased mRNA expression of IL-1β (p < 0.05). The histamine receptor H1R and the NF-κB signaling pathway were activated in the liver samples taken from the HC group. In conclusion, the elevated concentrations of LPS and histamine in the gut may be related to changes in the ruminal microbiota. LPS and histamine induced the inflammatory response in the ruminal epithelium, cecum epithelium, and liver. However, the cause–effect mechanism needs to be proved in future research. Our study offers a novel therapeutic strategy by manipulating ruminal microbiota and metabolism to decrease LPS and histamine release and to improve the health of dairy cows. [ABSTRACT FROM AUTHOR]

As a function in organization and management, coordination is used to adjust the interrelation of the individuals in the organization in order to achieve the ultimate goal. Coordination can make individuals groups in a whole, reduce the contradiction and conflict between each other and promote the realization of the overall goal. The research on the coordination of relationship between the port industry of China and the growth of economy plays an important guiding role for the port industry and healthy development of national economy. According to the correlation model between port industry and economic growth, the correlation factor between port industry and economic growth is extracted, and the coordination indicator system of the relationship between the port industry and economic growth is established. Then, this article makes correlation analysis of the standardization of indicators, removes the bigger indicators of correlation coefficient and eliminates the impact of the duplication of information between indicators in order to simplify the indicator evaluation system. The actual results by data calculation show that there were six obvious changes in the coordination degree of the relationship between the port industry and economic growth in China during the period from 1990 to 2014.

Lifting coarse mineral particles from thousands of meters of seabed to the supportive vessSel is a crucial part of exploitation of deep-sea mineral resources, and the vertical transportation part is a key component of the deep-sea mining system. Three typical vertical transportation schemes are discussed and compared from the aspects of working mechanism, structural scheme, transportation capacity, system efficiency and implementation feasibility in the context of commercial exploitation of deep-sea polymetallic nodules. The conclusion is that the hydraulic pipeline lifting system with a centrifugal pump is a comprehensive scheme. Furthermore, the basic composition and function of the hydraulic lifting system are introduced, and the transportation performance indicators and technical requirements under commercial mining conditions are analyzed. As the key equipment of the lifting system, the structural characteristics, design theory, transportation performance analysis methods and research progress of the lifting pump are described. A 1000 m sea trial was carried out. The lifting system, the tests of the centrifugal pump and the sea trial are introduced. [ABSTRACT FROM AUTHOR]

In order to improve the hydraulic performance of a deep-sea mining pump, this research proposed a multi-objective optimization strategy based on the computational fluid dynamics (CFD) numerical simulation, genetic algorithm back propagation (GABP) neural network, and non-dominated sorting genetic algorithm-III (NSGA-III). Significance analysis of the impeller and diffuser parameters was conducted using the Plackett–Burman experiment to filter out the design variables. The optimum Latin hypercube sampling method was used to produce sixty sample cases. The GABP neural network was then utilized to establish an approximate model between the pump's hydraulic performance and design variables. Finally, the NSGA-III was utilized to solve the approximation model to determine the optimum parameters for the impeller and diffuser. The results demonstrate that the GABP neural network can accurately forecast the deep-sea mining pump's hydraulic performance, and the NSGA-III global optimization is effective. On the rated clear water conditions, the optimized pump has a 14.65% decrease in shaft power and a 6.04% increase in efficiency while still meeting the design requirements for the head. Under rated solid-liquid two-phase flow conditions, the head still meets the design requirements, the shaft power is decreased by 15.64%, and the efficiency is increased by 6.00%. [ABSTRACT FROM AUTHOR]

Dealing with the environmental and climate risks caused by global warming has become a global consensus. As a sensitive area with particularly fragile ecological environment, the Nordic countries took the lead in making the commitment of "carbon neutrality" by the middle of this century. The green industry will play an important role during this process. Based on the patent data related to the green industry in Nordic countries, this paper studies the evolution characteristics and dynamic changes of influencing factors of patent citation network from 1980 to 2019 by using the social network analysis method and exponential random graph model. The research results show that: Nordic green technologies have gradually changed from passive development to active innovation from the source, and gradually diversified and subdivided in the development process; the connectivity and transitivity of the patent citation network are good and relatively stable in the evolution process; the connections of Nordic countries with non-Nordic countries are strong and gradually spread to distant regions; the awareness of patent property rights protection has gradually increased, and industry and academia are increasingly integrated, which all promote the formation of patent citation relationship. [ABSTRACT FROM AUTHOR]

To study the impact of Arctic routes on shipping networks, this paper uses an Arctic route system (ARS) model. Based on the evolution of the ARS, an improved weighted network evolution model (the BBV model) is used to predict the evolution of shipping networks from 2017 to 2035. Then, the multiple linkage analysis method is applied to extract the significant flows in the networks, and a competition network is built. The main results are as follows: (1) Significant flows in the maritime network under the influence of the ARS show an increasing trend and then a decreasing trend during evolution process. (2) According to multiple linkage analysis, Shanghai, Busan, and Tokyo have higher positions. (3) The overall network competition decreases. (4) In terms of the competitive landscape of China's container ports, Guangzhou has the strongest domestic competitive intensity. In addition, Chinese ports that face greater competition from foreign ports are always Shanghai and Shenzhen. One implication of analysis is that due to gradual influence of the ARS, port policy makers should implement different policies at different times. The paper also shows that some ports (such as Shanghai and Ningbo) should formulate cooperation agreements to promote ports development. [ABSTRACT FROM AUTHOR]

The Polar Silk Road (PSR) will open up China's maritime trade route through the Arctic to Northwest Europe and affect the freight function structure of China's coastal ports. This study evaluates ports' freight capacity and predicts the freight function structure of China's coastal ports under the PSR from four dimensions, namely, comprehensive/professional, function status, function scale and function hierarchy. The freight function structure is also compared with the current one. Results show that the ports in the Bohai Rim and Yangtze River Delta will have more diversified development and become the main force of the port system under the PSR. Coal will have an important position in most ports' cargo transportation under the PSR. The PSR will bring great economic development opportunities to the northern ports because of the influence of the sea route distance. The port function hierarchy is more obvious under the PSR, and the medium-sized ports are most affected by the PSR. We classify coastal portsaccording to the freight scale and freight function. An adaptive proposal for the government's port function planning is proposed in the conclusion. [ABSTRACT FROM AUTHOR]

In July 2017, Russia formally offered an invitation to build the Polar Silk Road (PSR) to China. Then, the White Paper of China's Arctic Policy was officially published in January 2018. It proposes the joint construction of the PSR to promote sustainable economic and social development in the Arctic region. Notably, the PSR aims to open up China's maritime trade route through the Arctic to Northwest Europe and influence the container hinterland pattern of China's coastal ports. This study assumes three scenarios to analyse and predict the evolution of the hinterlands of Chinese ports exporting to Europe under the PSR. The discrete selection model based on random utility is constructed to divide the dominant hinterland, probabilistic hinterland and major competitive hinterland of ports. The research shows that the cost and time, container throughput and risk have negative effects on a shipper's choice of port, whereas the sailing frequency has a positive effect. In general, the hinterlands of northern ports continue to expand under the PSR. Meanwhile, the hinterlands of the middle ports decrease first and then increase, and those of the southern ports contract. Overall, the northern ports are the most vulnerable to the changes of PSR attributes. [Display omitted] • Shippers' choice of port focus on transport cost, time, risk and sailing frequency. • The northern ports are the most vulnerable to the changes of PSR attributes. • The port hinterland's overall change is most vulnerable to the PSR navigation risk. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to investigate the effect of the modified extracorporeal circulation perfusion method during surgery for acute Stanford type A aortic dissection in patients who underwent stented elephant trunk implantation and arch replacement.Method: A total of 69 patients with acute Stanford type A aortic dissection who underwent stented elephant trunk implantation and arch replacement were retrospectively analysed from 2017 to 2018. According to the perfusion method of extracorporeal circulation, patients were divided into a routine perfusion (RP) group and a modified perfusion (MP) group. Clinical data were collected, including the time of extracorporeal circulation and deep hypothermic circulatory arrest, incidence of acute kidney injury and neurological complications, and comparisons between the two groups were conducted by using independent sample t-tests for normally distributed qualitative data, the Mann-Whitney U-test for skewed qualitative data, and the chi square test or Fisher's exact test for categorical data.Results: There were 55 (80%) males and 14 (20%) females in the entire cohort, and the mean ± standard deviation age was 50.4±9.0 years. A total of 53 (77%) patients were included in the RP group, and 16 (23%) were included in the MP group. Patients in the MP group were older (55.5±7.8 vs 48.8±8.9 years), and the difference was significant (p=0.008). Compared with the RP group, the time of extracorporeal circulation (218.0 [44.7] vs 246.0 [58.0] min; p=0.005) and deep hypothermic circulatory arrest (4.0 [2.0] vs 25.0 [10.0] min; p<0.001) was shorter, and the incidence of postoperative acute kidney injury (n=6 [37.5%] vs n=36 [67.9%]; p=0.029) was lower in the MP group; the differences were significant. Six (6) patients died in the RP group; no patients died in the MP group. The total in-hospital mortality rate was 8.7%.Conclusions: The modified extracorporeal circulation perfusion method is feasible, with satisfactory results. [ABSTRACT FROM AUTHOR]

Abstract EndMT plays an important role in the relationship between endothelial dysfunction and atherosclerosis. This work will elucidate the biofunction induced by miR-449a and lipid rafts in EndMT and development of atherosclerosis. The differential miRNA expression between atherosclerotic plaques and normal arteries were analyzed. The luciferase activities of AdipoR2 3' UTR treated with miR-449a were determined. ECs were dealt with miR-449a mimics or inhibitors, then cell proliferation and migration were assessed. Moreover, the expression of AdipoR2 and mesenchymal cell markers were analyzed. The influences of lipid rafts related to reciprocity between E-cadherin and AdipoR2 on TNF-α-induced damage in ECs were investigated. ApoE KO diabetic mice were used to explore the potential roles of miR-449a on atherosclerosis. Our results indicated that compared with normal arteries, 17 miRNAs were upregulated and 3 miRNAs were down-regulated in atherosclerotic plaques. The relative expression of miR-449a in plaques was significantly higher than that in normal arteries. MiR-449a suppressed AdipoR2 expression, additionally its interaction protein E-cadherin in ECs. MiR-449a enhanced expression of mesenchymal cell markers, induced cell proliferation and migration of ECs, regulated the interaction between E-cadherin and AdipoR2 interceded by lipid rafts. The miR-449a antagomir could protect against the development process of atherosclerosis in ApoE KO diabetic mice. In conclusion, miR-449a targeted to AdipoR2, and was a crucial mediator of EndMT and atherosclerosis in ECs through regulating E-cadherin bindability with AdipoR2 in lipid rafts. These results suggested that aim to lipid rafts and miR-449a in chronic EC inflammation response, was a feasible therapy strategy for atherosclerosis. [ABSTRACT FROM AUTHOR]

The ecosystem of ruminal microbiota profoundly affects the health and milk production of dairy cows. High-concentrate diets are widely used in dairy farms and evoke a series of metabolic disorders. Several studies have reported the effects of high-concentrate diets on the ruminal microbiome, while the effect of changes in ruminal microbial flora, induced by high-concentrate diet feeding, on the liver of dairy cows has not been studied before. In this study, 12 mid-lactating Holstein Friesian cows (weight of 455 ± 28 kg; parities of 2.5 ± 0.5; starting milk yield of 31.59 ± 3.2 kg/d; DMI of 21.7 ± 1.1 kg/d; and a DIM at the start of the experiment of 135 ± 28 d) were fitted with ruminal fistulas, as well as with portal and hepatic vein catheters. All cows were randomly divided into 2 groups; then, they fed with low-concentrate diets (LC, concentrate: forage = 40:60) and high-concentrate diets (HC, concentrate: forage = 60:40) for 18 weeks. The forage sources were corn silage and alfalfa hay. After the cows of two groups were euthanized over two consecutive days, ruminal microbiota; the concentration of LPS in the rumen content; cecum content; the levels of blood and histamine in rumen fluid, blood, and the liver; the histopathological status of the rumen and cecum; and the inflammatory response of the liver were assessed in dairy cows under conditions of subacute ruminal acidosis (SARA). These conditions were caused by high-concentrate diet feeding. All data were analyzed using the independent t -test in SPSS. The results showed that high-concentrate diet feeding increased the concentration of LPS and histamine in the rumen and plasma of veins ( p < 0.05). The abundance of Bacteroidetes at the phylum level, and of both Bacteroidetes and Saccharibacteria at the genus level, was decreased, while the abundance of Firmicutes at the phylum level and Oscillibacter at the genus level was increased by high-concentrate diet feeding. The decreased pH values of ruminal contents (LC = 6.02, HC = 5.90, p < 0.05) and the increased level of LPS in the rumen (LC = 4.921 × 10 5 , HC = 7.855 × 10 5 EU/mL, p < 0.05) and cecum (LC = 11.960 × 10 5 , HC = 13.115 × 10 5 EU/mL, p < 0.01) induced the histopathological destruction of the rumen and cecum, combined with the increased mRNA expression of IL-1β ( p < 0.05). The histamine receptor H1R and the NF-κB signaling pathway were activated in the liver samples taken from the HC group. In conclusion, the elevated concentrations of LPS and histamine in the gut may be related to changes in the ruminal microbiota. LPS and histamine induced the inflammatory response in the ruminal epithelium, cecum epithelium, and liver. However, the cause-effect mechanism needs to be proved in future research. Our study offers a novel therapeutic strategy by manipulating ruminal microbiota and metabolism to decrease LPS and histamine release and to improve the health of dairy cows.