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Aging is a necessary process for organisms.The antioxidant capacity in the body decreases, which induces the activation of inflammasomes, autophagy dysregulation, protein misfolding in the lens, resulting in lens opacification. With the increase of age, the secretion of melatonin and glutathione(GSH)gradually decreased, and the pro-oxidant/pro-inflammatory factors increased, which created ideal conditions for the formation of age-related cataract(ARC). A series of changes such as oxidative stress, inflammation and autophagy dysregulation accompany the occurrence of aging, which is also the basis of various diseases. Melatonin has antioxidant, anti-inflammatory, regulation of autophagy and circadian rhythm effects, and has shown benefits in age-related macular degeneration(ARMD), diabetic retinopathy(DR), and glaucoma. Although phacoemulsification and lens implantation have developed maturely, they consume a lot of medical resources. This article reviews the research of melatonin in ARC, which may prevent/delay the formation of ARC, thereby reducing the economic burden of patients and reducing the loss of medical resources.

Angiogenesis is a key step involving physiological and pathological processes, and pro/antiangiogenic factors are involved in angiogenesis throughout. Melatonin is a product synthesized by the pineal gland of the human brain and acts in various systems of the body. This article briefly describes the wide range of biological roles and physiological functions of melatonin, and summarizes that melatonin regulates pro-/anti-angiogenic factors(e.g., vascular endothelial growth factor/matrix metalloproteinase)under different conditions and is involved in angiogenesis in fundus diseases(e.g., age-related macular degeneration, diabetic retinopathy, and central serous choroioretinopathy); in addition, it also summarizes that melatonin regulates various cytokines, inflammatory factors and signaling pathways to produce anti-inflammatory, antioxidant and immune responses in fundus diseases, and thus obtaining the application and potential treatment of melatonin in fundus vascular diseases, with a view to providing new ideas and therapeutic targets for the treatment of fundus diseases.

Quasi-bound states in the continuum (quasi-BICs) offer unique advantages in enhancing nonlinear optical processes and advancing the development of active optical devices. Here, the tunable robust quasi-BICs resonances are experimentally achieved through the engineering of multiple-hole Si-metasurface. Notably, the quasi-BICs mode exhibits flat bands with minimal dispersion at a wide range of incident angles, as demonstrated by the angle-resolved spectroscopy measurements. Furthermore, we demonstrate a giant second-harmonic generation (SHG) enhancement by coupling a WSe2 monolayer to the quasi-BICs hosted in the metasurface. Leveraging the strong local electric field and high state density of the observed quasi-BICs, the SHG from the WSe2 monolayer can be enhanced by more than two orders of magnitude. Our work paves the way for effectively enhancing nonlinear optical processes in two dimensional (2D) materials within the framework of silicon photonics and is expected to be applied in nonlinear optical devices.

The integration of energy storage and wind power is an effective solution to address the challenge of system stability. Hydrogen energy storage system offers large storage capacities to supply electricity, making it highly promising for large-scale consumption of wind power. However, due to the uncertainty of wind power, the thermal demand of hydrogen energy storage system is uncertain when the system switches operation modes frequently. Therefore, the thermal energy demand of the hydrogen storage system in intermittent mode is considered comprehensively. Initially, the basic structure of the electricity and heat integrated energy system connected to the hydrogen energy storage system is introduced, and a wind-hydrogen hybrid system composed of a wind farm and hydrogen energy storage is described. Furthermore, a robust interval optimization dispatch model for the electricity-heat integrated energy system is proposed, taking into account the uncertainty of the thermal balance demand of the wind-hydrogen hybrid system. Finally, based on the duality theory, the proposed model is transformed into a mixed-integer linear programming problem. By comparing and analyzing the optimization results of various scenarios through numerical examples, the effectiveness of hydrogen energy storage in promoting wind power consumption and increasing the comprehensive energy utilization rate of the system is verified. It is also demonstrated that the system's efficiency can be improved by considering the working temperature of electrolytic and fuel cell, leading to an increase in the grid-connected power of wind farms.

The Loess Plateau is an important region for soil and water conservation and ecological construction in China. Exploring the spatio-temporal variations in soil conservation and water conservation services and their relationships in Loess Plateau under the background of land consolidation projects is of great significance for ecological protection and quality development in the Yellow River Basin. Taking Yan’an city as the research area, this paper used the InVEST model to quantitatively evaluated spatio-temporal variation characteristics and trade-off/synergy relationship of the soil conservation and water conservation services from 2010 to 2018. According to the implementation data, the relationship between the gully control and land consolidation (GCLC) project in various counties of Yan’an city and soil conservation and water conservation service was analyzed. The results showed that the total amount of soil conservation services in Yan’an City were 4.07 × 106 t and 3.75 × 106 t in 2010 and 2018 with a decrease of 7.76%, and with low spatial clustering characteristic. The total amount of water conservation services were 2.01 × 1010 mm and 2.03 × 1010 mm in 2010 and 2018 with a increase of 0.56%, and with high spatial clustering characteristic. There is a synergistic relationship between soil conservation and water conservation services in most area of Yan’an city. From 2010 to 2018, the effect of the GCLC projects on soil conservation and water conservation services in Yan’an city is not significant. The GCLC project can effectively alleviate the situation of sharp decline of cultivated land area and insufficient food production capacity.

Missing data, occurring in clinical trials due to various reasons, will cause information loss of the original data and reduce the robustness and validity of the research results. Therefore, missing data should be dealt with caution in clinical trials. This article introduces the causes and types of missing data, as well as several common methodological approaches to addressing the problem, in order to promote researchers' understanding and improve the quality of handling missing data in trials. Nevertheless, the best way to deal with missing data is to prevent or reduce data loss in clinical trials, rather than relying on post hoc statistical analyses.

The factors that affect rail's performance and quality mainly include fractures, abrasion, scratches, wear, etc. Among them, wear directly changes the profile of the rails. The first step in repairing the rail profile is to accurately measure the rail profile data, and then to calculate the wear of the rail by applying rail matching algorithm. In practical applications, the rail profile is variable and the measurement accuracy requirement is as high as ±0.2 mm. The matching algorithm needs to be able to adapt to various abnormal rail profiles without reducing the matching accuracy due to abnormal rail profiles. Therefore, designing with rail profile matching algorithm is highly difficult. The classic iterative closest point (ICP) algorithm is able to realize quick point cloud matching, but it has the shortages such as high requirements for initial input data, being prone to falling into local optimal solutions, and being susceptible to interference from noisy points, resulting in big matching errors. For the purpose of this article, an improved two-step rail matching algorithm was proposed. Firstly, the geometric features of the rail profile are used for fast rough matching, providing a high-quality initial input for the ICP algorithm. Then, the improved overlay weight ICP algorithm is used to quickly and accurately match the measured rail profile point cloud data with the standard rail profile point cloud data to calculate the rail wear data. The matching test results of various degraded rail profiles show that, for the wear at the top of the rail, the wear value calculated by the ICP algorithm with weights proposed in this paper is 0.763 mm less than the average error of the classical ICP algorithm. It has a good matching effect and can be used for the calculation of rail wear.

SiC whiskers (SiCw)/WC binderless cemented carbides were prepared by spark plasma sintering (SPS), using SiCw as the toughening phase. The effects of sintering temperature and SiCw content on the microstructure and properties of the SiCw/WC cemented carbides were investigated. The results show that the WC sintered body with the relative density higher than 99% can be obtained by spark plasma sintering at 1800 ℃, and the Vickers hardness and fracture toughness reach 25.99 GPa and 4.99 MPa∙m1/2, respectively. The sintering properties and fracture toughness of the SiCw/WC sintered body can be improved by adding the appropriate amount of SiCw. The fracture toughness reaches 6.80 MPa∙m1/2 with the SiCw mass fraction of 0.6%. However, the toughening effect to the WC matrix decreases with the further increase of content SiCw.

As a device for missile-borne system to transmit and receive electromagnetic waves, the functions of missile-borne antenna are becoming more and more abundant. The shared-aperture antenna can improve the aperture utilization rate of missile seeker and can avoid radiation interference between antennas. This paper proposes a low profile circularly polarized shared-aperture antenna for missile seeker antenna based on the theory of microstrip circular polari-zed antenna. More specifically, the sequential rotation feed technology is adopted for the rectangular microstrip antenna in the high-frequency C-band part, while the orthogonal double feed technology is adopted for the cross microstrip antenna in the low-frequency S-band part. The nested shared-aperture antenna structure is adopted to realize the design of shared aperture antenna of 63 mm×63 mm×1.574 mm. The reflection coefficient is less than -10 dB in the frequency bands of 4.87~5.13 GHz and 2.49~2.51 GHz. The relative bandwidth of high-frequency antenna is 8.1% and that of low-frequency antenna is 0.4%. The axial ratio of the two antennas in the maximum radiation direction at the center frequency is less than 3 dB. The experimental data show that the shared-aperture antenna designed and applied to the missile-borne antennacan significantly improve the aperture utilization of the missile seeker, and can also eliminate the deterioration of the radiation performances caused by the mutual coupling of antennas.

Antarctica recorded a Cenozoic geologic history of continental growth, breakup and dispersal, global cooling and the development of continental-scale Antarctic ice sheet. Despite the importance of Antarctica, there has not been an integrated view of the Cenozoic tectonic evolution of the region as a whole. In this Review, we identify the Tasmania gateway and Drake Passage, and present their overlapping and interconnected tectonic, magmatic and sedimentary history of Antarctica, South America and Australia. Antarctic Circumpolar Current (ACC), which occurred in the late Eocene to early Oligocene, was most impacted by the opening history of Drake Passage and the Tasmania gateway. Our comprehensive analysis and contrastive study show that the beginning of ACC corresponds to the transition from "warmhouse" to "coolhouse" phase at 34 Ma, indicating the development of ACC was controlled by the tectonic gateways, which in turn affected global climate. We conclude by briefly summarizing the Cenozoic geologic history of the Antarctic system as a whole, and how it provides insight into continent-ocean configuration patterns and what key topics must be addressed by future research are disscussed as well.

At present, most high-accuracy single-person pose estimation methods have high computational complexity and insufficient real-time performance due to the complex structure of the network model. However, a single-person pose estimation method with high real-time performance also needs to improve its accuracy due to the simple structure of the network model. It is currently difficult to achieve both high accuracy and real-time performance in single-person pose estimation. For use in human–machine cooperative operations, this paper proposes a single-person upper limb pose estimation method based on an end-to-end approach for accurate and real-time limb pose estimation. Using the stacked hourglass network model, a single-person upper limb skeleton key point detection model is designed. A deconvolution layer is employed to replace the up-sampling operation of the hourglass module in the original model, solving the problem of rough feature maps. Integral regression is used to calculate the position coordinates of key points of the skeleton, reducing quantization errors and calculations. Experiments show that the developed single-person upper limb skeleton key point detection model achieves high accuracy and that the pose estimation method based on the end-to-end approach provides high accuracy and real-time performance.

The performance of Polystyrene microporous foaming (PS-MCF) materials is influenced by their microstructures. Therefore, it is essential for industrializing them to investigate the relationship between their microstructure and material properties. In this study, the relationship between the microstructure, compressive property, and thermal conductivity of the PS-MCF materials was studied systematically. The results show that the ideal foaming pressure of PS-MCF materials, obtaining compression performance, is around 20 MPa. In addition, the increase of temperature causes the decrease of sample density. It effects that the compression modulus and strength increase with the decrease of foaming temperature. Because the expansion rate and cell diameter of the PS-MCF materials reduce the thickness of cell wall, they are also negatively correlated with their mechanical properties. Moreover, there is a negative linear correlation between the thermal conductivity and cell rate, whereas the cell diameter is positively correlated with the thermal conductivity.

Constructed wetland plays an important role in the removal of micro-polluted water pollutants in urban water sources. However, the water purification capacity and influencing factors of the constructed wetlands still need to be explored. This study monitored the turbidity, ammonia nitrogen (NH3-N), dissolved oxygen (DO), and chemical oxygen demand (COD) at the water inlet and outlet of Shijiuyang Wetland in Jiaxing City from 2019 to 2021. The results showed that the turbidity and the wetland turbidity removal rate stayed high. The DO couldn’t meet national standard III for surface water during the high temperature time in summer, and NH3-N and COD are stable within national standard III. The partial regression analysis shows that the addition of chemicals is the most important factor affecting the turbidity. Temperature had the most important affect to NH3-N and DO, the higher the temperature, the lower the NH3-N value and the DO. The flow rate is the most important factor affecting the COD, the higher the flow rate, the lower the COD. Moreover, this paper proposes operation and maintenance improvement measures for the problem of excessive turbidity and DO in Shijiuyang Wetland. The research results are conducive to improving the understanding of water security in the Yangtze River Delta region.

Outcomes-Based Education (OBE) is the core concept of professional accreditation in engineering education, and is a teaching and learning approach that determines teaching strategies based on learning outcomes. In the context of new engineering, it is important to actively cultivate high quality composite new engineering talents with international competitiveness that are compatible with the emerging industries, and improving their teaching effect is important to accomplish the training objectives and graduation requirements.This paper analyzes the necessity of using virtual reality technology in the teaching system, explains the application and development of OBE concept and virtual simulation technology in the teaching system, and finally proposes specific objectives, ideas and methods for the construction of virtual simulation training teaching system for intelligent manufacturing.

The contaminated soil caused by an organophosphorus pesticide production enterprise was evaluated, in order to provide constructive suggestions for the future remediation work. This study follows the basic technical route of sampling with the method of distribution, and combined with the relevant national laws and regulations and the actual situation of the site to evaluate and analyze, and finally find out whether the characteristic pollutants of the contaminated site exceed the standard and the environmental health risk. The results show that in the selected contaminated sites, the method can be implemented and obtained clear analysis results. The characteristic pollutants such as benzene, ethiophosphorus and parathion are far beyond the national standards, and seriously endanger the life and health of the surrounding residents. Conclusions:1) In the assessment of some contaminated sites, especially those contaminated by organophosphorus pesticides, the sampling method has the advantages of uniform, extensive, accurate and low sampling cost;2) The pollutants related to the polluted site, especially the volatile organic compounds such as benzene and parathion, are much higher than the limit value, and the peculiar smell is obvious, which seriously endangers the life and health of surrounding residents, causing the attention of relevant departments and providing guiding opinions for the future restoration work. In the future, the pollutants in the polluted site will be effectively removed through the restoration work. To ensure the life and health of neighboring residents, and promote China's ecological civilization construction.

An accelerated life test is designed and a kind of analysis method for solenoid valve failure based on multi-physics finite element model is put forward due to the uncertainty of failure mechanism and the lack of effective means to analyze faults. Firstly, the model of temperature field is built based on ANSYS finite element software and the temperature distribution of components is calculated. Then, the temperature is added to the mechanical stress field as the new load and the coupling stress is received based on the combined action of thermal stress and mechanical stress. Finally, a kind of degradation failure mechanism of the solenoid valve, through the comparison of experimental data and simulation results, is obtained based on the comprehensive analysis of temperature and coupling stress. The result shows the high temperature produced by coils can fail the insulation between coil wires. Meanwhile, the coupling effect of thermal stress caused by high temperature and the mechanical stress can squeeze coils resulting in the continuous short-circuit of coils. When the electromagnetic force of iron core is lower than its threshold, the iron core will not overcome the elasticity to move up and down and finally the failure of the SV will happen. This prediction method can be widely applied to the other fault diagnosis types of degradation failure of solenoid valves. The result can be provided for the optimization and researched on prolonging life of the solenoid valve.

Short-term photovoltaic power forecasting is of great significance for maintaining the security and stability of the power grid and coordinating the utilization of resources. As one of the Deep Learning Methods, Recurrent Neural Network (RNN) is widely used in time series prediction but lacks the ability of parallel computing. With good prediction effect, RNN is faced with the problem of long training time. In this paper, Sliced Recurrent Neural Network (SRNN) is applied to PV power prediction to guarantee the ability of parallel computing. The research result shows that compared to other commonly used models, SRNN can greatly speed up the training of Deep Learning Network with over 4 times higher training speed of the application of PV power prediction than that of ordinary RNN structure like LSTM and GRU. The accuracy of SRNN model is also improved by 0.1102 mae, which is significantly ahead of the others, as its parallel structure causes the more efficient parameter update, thus achieving ideal effect in PV prediction.

The integrated energy system creates the possibility for the interconnection and coordination of different energy sources, and is an effective means to improve the energy use of the system, increase energy efficiency, and reduce environmental pollution. At present, the planning of distributed energy stations for integrated energy systems mostly focuses on equipment selection and equipment capacity. However, there are relatively few studies on the location of energy stations and pipeline layout planning. Firstly, this paper proposes a distributed energy station location method based on the improved p-median model, which combines the energy supply path of the energy station with the actual transportation network, and introduces the weight coefficient of multi energy load to reflect the diversity of energy demand of load. Finally, the specific solution method is given, and the rationality and feasibility of the proposed method are verified by an example.