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Hypertensive disorders of pregnancy (HDP) is one of the leading causes of maternal and perinatal mortality worldwide, with increasing incidence and mortality year by year. In 2023, the U.S. Preventive Services Task Force (USPSTF) updated the recommendation statement on screening for hypertensive disorders of pregnancy by evaluating the latest research evidence and analyzing the benefits and harms of screening for HDP. The recommendation, compared with the 2017 version, further affirms the importance of blood pressure measurement in screening for HDP, affirms substantial net benefit, and recommends blood pressure measurement throughout pregnancy to screen for HDP. This article explores and analyzes the key points of this recommendation based on the RIGHT statement for introductions and interpretations of guidelines in Chinese (RIGHT for INT) and its implications for guiding general practitioners in China.

Achieving the best wideband stealth performance under the limited weight constraint is the goal pursued in stealth aircraft radar absorbing coating（RAC） application schemes design. To meet the need for the integrated application of various kinds of RACs on stealth aircraft， an automatic optimization method for the application programme of RAC was established. Firstly， the electromagnetic fields of the model under different frequencies， azimuths and polarizations were simulated based on the finite difference time domain method. The total electromagnetic field was obtained by normalization and weighted calculation of the electromagnetic fields.Then， the total electromagnetic field was divided according to the specific direction and quantity. Each partition was loaded with the corresponding RAC. The reflection coefficient of the RAC was calculated by the transfer matrix method to superimpose the effect of the RAC on the electromagnetic field. The near-far field transformation was performed on the total electromagnetic field after loading with RAC. In this way， fast computation of radar cross section （RCS） was implemented. Based on the improved simplex method and Karush-Kuhn-Tucker condition， an automatic optimization method is established. The objective function was reducing RCS of the target or reducing weight of the absorbing coating. Finally， taking traveling wave plate as an example， the application plan of three thicknesses of RACs was optimized. The goal of optimization was to reduce total weight of the coating. Compared with the 1.5 mm coating plan， the optimization program can reduce the weight by 50%， with the RCS of traveling wave plate increasing by on more than 1 dB. The optimization effect is remarkable.

Objective There is limited research on the impact of mechanical method connecting passage construction on mainline tunnels and surrounding soil of metro shield interval in water-rich sandy stratum. Method Taking a metro shield tunnel interval project with mechanical method connecting passage construction in water-rich sandy stratum as example, a numerical model is established using ABAQUS finite element software to simulate and analyze the entire process of this engineering. The effects of mechanical method connecting passage construction on mainline tunnels and surrounding soil are investigated. The calculation results are compared with actual engineering monitoring data to verify the reliability of the proposed numerical model. Result & Conclusion Land subsidence along the longitudinal direction of the mainline tunnel and connecting passage caused by mechanical method connecting passage construction exhibits a U-shaped curve, with a maximum land subsidence value of 4.60 mm. The effects of the construction on mainline tunnel deformation are mainly vertical deformation and horizontal deformation along the mainline tunnel. The maximum vertical deformation of the mainline tunnel is 1.08 mm, and the maximum horizontal deformation is 1.28 mm. During construction, the maximum stress in the mainline tunnel suddenly increases with the breakthrough of the connecting passage portal, reaching 52.54 MPa upon completion of the construction. Actual monitoring data show that the fitted land subsidence monitoring data aligns with the trend of numerical calculation results, validating the reliability of the numerical calculations.

The superhydrophobic coating can effectively prevent the intrusion, adhesion and condensation of water-containing corrosive media on the surface. However, the poor mechanical and chemical stability of traditional superhydrophobic coatings significantly limits their application in complex and harsh environments. In this study, a superhydrophobic PDMS-EP@SiO2-GO coating was formed on the surface of Q345 steel sheets by using a composite substrate of graphene oxide(GO) and nano silicon dioxide(SiO2) with polydimethylsiloxane(PDMS) and epoxy resin(EP), combined with spraying technology. The superhydrophobic, self-cleaning, anti-fouling, mechanical wear resistance, chemical corrosion resistance and anti-corrosion properties of the coating were studied. Results showed that the water contact angle of PDMS-EP@SiO2-GO was 166.57°, and the sliding angle was less than 3°. Due to the strengthening effect of GO on the coating substrate, the coating maintained a contact angle of more than 155° for liquids with water temperatures ranging from 20 ℃ to 100 ℃ and a contact angle of more than 160° for acidic/alkaline solutions. The sliding angle was less than 4° under the above conditions. After sandpaper friction(total friction length of 40 m) and 30 cycles of tape-peeling tests, the coating still exhibited good superhydrophobic ability, with the contact angle remaining above 152°. In addition, PDMS-EP@SiO2-GO, with excellent water resistance, demonstrated good anti-fouling and self-cleaning properties. In terms of corrosion protection, the lowest frequency impedance of PDMS-EP@SiO2-GO increased by an order of magnitude, and the charge transfer resistance increased by two orders of magnitude, showing excellent corrosion resistance. PDMS-EP@SiO2-GO addressed the problem of weak mechanical and chemical stability in traditional superhydrophobic coatings and enabled the persistent protection of the metal substrate. The as-prepared superhydrophobic coating, with good practicability, contributes to the safe and reliable service of mechanical equipment throughout its life cycle.

【Objective】The objective of this study is to investigate the resource allocation problem in Optical Wireless Communication (OWC) systems using Rate Splitting Multiple Access (RSMA) technique. We propose a joint precoding matrix and rate allocation algorithm based on linear approximation to enhance the system reliability and performance.【Methods】We employ variable transformation and linear approximation techniques to convert the non-convex fractional functions into convex ones. By using the joint precoding matrix and rate allocation algorithm, system resources can be effectively allocated to improve system performance. The optimization problem is solved using a continuous iterative algorithm to obtain the optimal solution.【Results】Simulation results demonstrate that the proposed joint optimization scheme significantly reduces the system outage probability and exhibits a fast convergence rate. This indicates that the proposed method can provide more reliable and efficient communication performance in the RSMA-OWC system, which is based on rate splitting access.【Conclusion】This study provides an effective resource allocation method for RSMA technology in OWC systems, enhancing system reliability and performance. Further research should focus on the challenge of system outage probability in RSMA-OWC systems, as well as resource allocation, precoding design, and application scalability. This study offers valuable insights to promote the application and development of RSMA technology in the field of OWC.

Typhoons are among the most significant natural disasters affecting the eastern and southern coastal regions of China, inflicting substantial annual damage on both coastal and inland areas. Since the initiation of the reform and opening-up policy, the socioeconomic development of the coastal regions of China has been swift, leading to increased exposure to typhoons. In the context of global climate change, typhoons are expected to increase in frequency and intensity in China. Therefore, researching on the spatiotemporal pattern characteristics of typhoons impacting China is of critical importance for understanding the impact patterns and risk changes of typhoon disasters, as well as for formulating policies on disaster response, prevention, and mitigation. This study aims to provide valuable insights into the formulation of such policies. Based on these objectives, this study utilized a comprehensive dataset, including county-level socioeconomic and disaster statistics, historical typhoon wind and rainfall data, and high-precision topographic data. Using county-level administrative regions as spatial units, this study employed various methods, such as time-series statistical analysis, gravity model, geographical detector, spatial correlation analysis, and geographically weighted regression, to analyze the spatiotemporal distribution patterns and influencing factors of typhoon disaster conditions in China from 1978 to 2020. The findings of this study are as follows: (1) The number of deaths and missing persons, quantity of damaged housing, death, and missing rate per million people, and proportion of direct economic loss to GDP caused by typhoon disasters have all shown a declining trend, indicating significant achievements in disaster prevention and mitigation efforts. (2) The center of gravity of typhoon disaster-related losses has shifted southward, corresponding with the economic development of coastal regions, demonstrating a reduced disaster impact in coastal areas and an increased impact in inland areas. (3) Wind and rain induced by typhoons are the primary driving factors of disaster conditions, and topographical factors are also drivers of casualties and crop loss. (4) The two major regions, Zhejiang-Northern Fujian and Western Guangdong-Eastern Guangxi, exhibit significant characteristics of disaster condition agglomeration, closely related to typhoon activity patterns and levels of economic development. (5) There is a negative correlation between the gross local product and disaster conditions in some areas, reflecting the role of socioeconomic development in enhancing the capacity for disaster prevention and mitigation.

To evaluate the mechanical property of concrete materials rapidly, a fast prediction model of the concrete equivalent modulus is proposed based on the random aggregate model and scaled boundary finite element method (SBFEM). First, a random aggregate model of meso-concrete is employed to construct the representative volume element (RVE) according to the aggregate content, gradation, shape, etc. Second, the RVE model is transformed to be a grayscale image and stored as a digital matrix. The quadtree mesh is partitioned automatically for simulation by SBFEM. There are only six types of unique subdomains, and the hanging node does not affect the simulation accuracy. The global stiffness matrix can be assembled directly according to the six subdomain stiffness matrices. Finally, the equivalent modulus is predicted by using the numerical homogenization method. Several numerical examples are employed to verify this model, and the results are compared with that of other methods. The result indicates that the proposed model can efficiently determine the equivalent modulus. Furthermore, the effect of the aggregate gradation, shape, porosity, and pore water are studied and analysed in this work. The proposed model is potential and helpful in predicting the mechanical properties of concrete or other composite materials.

Myopia is one of the leading causes of visual impairment and has become a major global public health concern with the rapidly increasing prevalence worldwide. Due to the trend of myopia towards younger age groups, accurate prediction of the occurrence and progression of myopia could help to provide targeted interventions for high-risk population and myopia patients in children and adolescents, in order to delay myopia onset or slow myopia progression. In recent years, various myopia prediction models have been built based on evidence-based medicine such as baseline ocular biometric data, refractive status, environment factors, genetic factors, and lifestyle have been established. The interaction of genetic and environmental effects on etiology of myopia have been established, with the continuous innovation of genetic research methods, specific genes with higher predictive power in the future will also be applied in the prediction, prevention and control of myopia. This article summarize the content, performance and research progress of myopia prediction models, which could serve as a useful reference and guidance for the prevention and control of myopia in children and adolescents.

Objective To explore the neurophysiological responses of patients′ fear in real treatment scenarios, and to construct a assessment model of children′s dental fear and anxiety (DFA) based on physiological data. Methods Totally 166 children under the age of 14 who received treatment at the Beijing Children′s Hospital Department of Stomatology were included in the study. The Chinese version of the modified Children′s Fear Survey Schedule-Dental Subscale (CFSS-DS) was used to assess dental fear and anxiety scores in children. A wrist-worn physiological data collection device was used to continuously measure subjects′ heart rate (HR) and galvanic skin response (GSR) during the treatment. Repeated measures analysis of variance was used to test for differences in physiological data before, during and after treatment. Pearson′s correlation analysis was used to analyze the relationship between physiological data and CFSS-DS scores before, during, and after treatment. A Least Absolute Shrinkage and Selection Operator(LASSO) regression model was established to assess dental fear and anxiety among children, and Leave-One-Out (LOO) was used for cross-validation. Results There were significant differences in the changes of each dimension of physiological data before, during, and post treatment(P＜0.05). The Pearson′s correlation coefficient (r) between the LASSO model predictive values and the CFSS-DS scores was 0.30 (P＜0.05), which indicated a good predictive accuracy of the model. Conclusions The assessment model might achieve objective and automated measurement of dental fear and anxiety in children.

Geographic atrophy(GA)is an intermediate and advanced stage of age-related macular degeneration(ARMD). Due to the complex pathogenesis of GA, there are no effective treatments at present, and eventually patients will lose central vision. Studies have shown that excessive activation of the complement system is closely related to the occurrence and progression of GA. This review will offer a summary of the clinical features, pathogenesis, the role of complement system in the pathology and the treatment progress of GA.

According to 2019 statistical data, the nationwide surgical volume reached 69.3 million patient cases, with pulmonary surgeries constituting a vital component and showing an annual increase. However, as the number of surgeries rises, so does the incidence of perioperative complications, including thrombosis, which adversely affects patient outcomes. Therefore, understanding of the causes, risk factors, and mechanisms of thrombosis in the context of pulmonary surgeries, as well as implementing effective preventive measures, can mitigate the adverse effects of thrombosis related to pulmonary surgeries. This article discusses the incidence, risk factors, clinical manifestations, treatment, and prognosis of postoperative thrombosis in pulmonary surgeries, aiming to provide new insights for related clinical research.

Excessive phosphorus in water can lead to environmental pollution problems such as eutrophication，and effective methods for removing phosphate have attracted the attention of researchers. The electrode material（ZrAC） of Zr-based metal doped activated carbon was successfully prepared by liquid-phase impregnation coupled calcination method and used for phosphorus electro-adsorption. The composite activated carbon material was characterized by XRD，XPS，SEM，EDS and TEM. The results indicated that the synthesized ZrAC material exhibited favorable crystal structure characteristics，while the incorporation of Zr provided an ample number of adsorption sites for efficient phosphate removal. The kinetics of the prepared electrode material during the phosphate removal process followed a pseudo-second-order kinetic model. At a voltage of 1.0 V，the PO43- electro-adsorption capacity could reach 29.43 mg/g，and the external voltage significantly improved the phosphate removal effect. The capture of PO43- by ZrAC was primarily attributed to the formation of Zr—O—P bond，thereby enhancing the adsorption capacity and rate of the electrode material towards PO43-. Moreover，the synthesized ZrAC electrode material exhibited excellent resistance to interference and stability during electro-adsorption.

Central retinal artery occlusion(CRAO)refers to occlusion of the central retinal artery(CRA), which acts as the primary blood supply to the inner neurosensory retina, and leads to an acute loss of vision and permanent visual disability. The natural history of visual prognosis in CRAO is generally poor. Despite a variety of treatment options have been studied, such as ocular massage, anterior chamber paracentesis, hyperbaric oxygen therapy(HBOT)and intra-arterial infusion of tissue plasminogen activator(tPA), but there is currently no evidence-based management strategies for the treatment of CRAO. Furthermore, the efficacy of all available managements is debatable and many have uncertain risks. This review will offer a summary of the currently known treatment options for CRAO and probe into their safety and efficacy on the prognosis of CRAO.

At present, the research on spent fuel reprocessing technology, especially the research on solvent extraction technology has been paid more and more attention. The radionuclides in aqueous solution were extracted with organic diluent containing extractant. This paper aims to review and discuss the extraction performance and radiation stability of phosphorus-containing extractants, especially neutral phosphorus extractants, used in spent fuel reprocessing(solvent extraction) in the past decade. For neutral phosphine extractants, the extraction performance and radiation stability are affected by other factors such as its own structure, diluent type, etc. The decrease of the number of P—O bonds in the extractant would improve the extraction performance. The increase of alkyl chain length or the introduction of branched chain(such as methyl, ethyl and phenyl) can improve the radiation stability. In addition, the organic phase with ionic liquid as diluent can reduce the irradiation of the organic phase. Therefore, the study of the relationship between the structure of phosphorus-containing extractants and their extraction performance and radiation stability are conducive to select the extractant suitable for spent fuel reprocessing. It is also of great significance to select the structure with excellent extraction performance and radiation stability to guide the synthesis of new phosphorus-containing extractants.

Power hardware-in-the-loop (PHIL) testing has become indispensable for the rapid, modular, and cost-saving development of automotive components. This article focuses on PHIL tests composed of entire powertrains that exchange speed and torque signals with vehicle simulations. Previous studies pointed out the importance of promptly following the references from the virtual simulation environment to replicate realistic driving conditions and introduced control strategies to cope with the challenges associated with this setup. However, a comprehensive comparison of the different control strategies has not yet been carried out. To fill this gap, the concepts are first investigated in-depth in simulations and are then, rigorously validated on a state-of-the-art powertrain test bed under highly dynamic driving scenarios, including full-braking. Furthermore, an improvement of existing shaft torque control approaches, which are mainly based on feedforward control, is proposed to better compete with the other methods. The proposed extension shows higher resilience to low accuracy of torque actuators, while the other concepts exhibit greater robustness against time delays. The results from the direct comparisons are summarized and allow the appropriate selection of control strategies for specific use cases.

Overexpression of methyltransferase-like 3 (METTL3) is significantly correlated with the malignancy of lung cancer (LC). In the present study, we demonstrated that METTL3 had higher levels in LC tissues relative to normal tissues. METTL3 showed superior sensitivity and specificity for diagnosis and identification of LC functions. In addition, silencing METTL3 resulted in enhanced ferroptosis sensitivity, whereas overexpression of METTL3 exhibited the opposite effect. Inhibition of METTL3 impeded LC growth in cell-derived xenografts. Further exploratory studies found that METTL3 stimulated the low expression of transferrin receptor (TFRC), which was critical for ferroptosis sensitization in LC cells induced by silenced METTL3, as silencing of TFRC caused a decrease in negative regulators of ferroptosis (FTH1 and FTL) in METTL3 knockdown A549 and PC9 cells. Finally, we confirmed that METTL3 attenuation effectively maintained the stability of TFRC mRNA. In conclusion, we reported a novel mechanism of METTL3 desensitization to ferroptosis via regulating TFRC, and an appropriate reduction of METTL3 might sensitize cancer cells to ferroptosis-based therapy.

AIM: To explore a more convenient and accurate method for evaluating the anterior chamber angle width based on the Van Herick method.METHODS:A total of 58 patients(69 eyes)with age-related cataract who visited our hospital between January and December 2021 were included. They were divided into the chamber angle width ≥1/2 corneal thickness(CT)group(44 eyes of 37 cases)and 0.05), while the differences of chamber angle degrees of other quadrants were all statistically significant(P

The concentration, complexity, and significant anisotropy of in-situ stress make it a pressing and challenging issue in engineering geology safety in strong tectonic activity areas. This paper firstly analyzes the application and existing problems of in-situ stress measurement in deep-buried underground engineering in strong tectonic activity areas. Then, it focuses on the application method, technology, and roles of real-time in-situ stress monitoring in deep underground engineering within tectonically active regions. Finally, it discusses the problems that need to be considered in the application of in-situ stress measurement and real-time monitoring. The results show that in the strong tectonic activity area, relying solely on limited deep hole in-situ stress measurements to determine overall stress design parameters for deep underground engineering is inadequate. A comprehensive study of the three-dimensional in-situ stress field is necessary to reveal its spatial distribution characteristics. Different in-situ stress design parameters should be used for different positions of the deep-buried underground project to avoid engineering waste or engineering damages caused by large or small in-situ stress design parameters. In the strong tectonic activity area, the disk core density is inversely proportional to the measured magnitude of the in-situ stress, and the depth range that has yet to form in the cake-shaped core often has the highest in-situ stress and the most concentrated stress, and the deep underground engineering should avoid this depth range. While a major earthquake or major engineering geological problem occurs, real-time monitoring of in-situ stress can dynamically reveal the relative change trend and evolution process of the in-situ stress magnitude of a specific structural site. It can calculate the absolute value of the in-situ stress state in different time domains during the real-time monitoring period without carrying out new absolute in-situ stress measurements. Regional crust stability and deep-buried engineering geological safety risks can be quickly evaluated, and quantitative in-situ stress design parameters and the stress-strain reserved threshold for preventing deformation and breaking can be provided for the damage repair of deep-buried engineering and the risk of fault activity can also be assessed. The research results will offer geological security for the planning, construction, and safe operation and maintenance of major projects in strong tectonic activity areas.

This study aims to solve the significant deformation issue in the soft surrounding rocks under high in-situ stress encountered during the construction of the Muzhailing Tunnel on the Weiyuan–Wudu Expressway. We established a three-dimensional geological model to invert the in-situ stress field using ANSYS based on measured in-situ stress data in the engineering area. Then, we calculated and analyzed the deformation of the surrounding rocks by combining the inverted results with the Hoek deformation prediction formula. The result showed that the in-situ stress field in the engineering area was primarily controlled by faults, with secondary influences from rock strength and topography. In the intense tectonic deformation zone, horizontal principal stress values are generally lower than in the weak structural deformation zone. The relationship between the three principal stresses along the tunnel axis is SH>Sh>SV. The maximum horizontal principal stress in the intense tectonic deformation zone was the highest in the G8 section and the lowest in the G6 and G11 sections. In the weak structural deformation zone, horizontal principal stress gradually increases from the G12 section until it decreases due to reduced burial depth starting from the middle of the G14 section. The maximum horizontal principal stress orientation was generally in the NE direction, and the extruded structural belt between the faults was mostly deflected to the NEE –nearly EW direction. The deformation of the surrounding rocks was affected by rock mass strength and in-situ stress field, with rock mass strength playing a dominant role. The deformation of the surrounding rocks is mainly concentrated in the range of 20 to 80 cm, and the deformation levels are mainly moderate and intense.

Selecting appropriate reservoir volume is a necessary premise to ensure the normal operation of the hydraulic system. In order to provide a reference for the reasonable calculation of the self-pressurized hydraulic reservoir volume of civil aircraft,based on the general design requirements of SAE AS5586 aircraft hydraulic system reservoir,the calculation methods for variable volume produced by actuator,hydraulic accumulator and physical properties of oil are introduced and analyzed in this paper. A set of step by step reservoir volume calculation methods are proposed to get the design value of the reservoir. Taking an aircraft hydraulic reservoir volume calculation as an example,the calculation method of each variable volume in the system is deduced. The results show that the reservoir of the hydraulic system of this type of aircraft can meet the requirements in each flight phase.

Objective The stability of underground chambers such as mine tunnels and transportation tunnels is closely related to the stress environment of the surrounding rock mass and the geological conditions of the area. Analyzing the relationship between deep-seated stress and factors such as the orientation and shape of underground chambers can help to proactively mitigate the risks associated with chamber excavation. Methods This study, set against the background of the rock burst accident on October 20th in the Longyun Coal Industry area in Shandong, reveals the current stress environment of the shallow crustal layers in western Shandong through in-situ stress measurement and monitoring work. Results According to the characteristics of the current ground stress field near the Longyun coal mining area, the study investigates the regional stress background that led to the rock burst accident and proposes corresponding prevention and control suggestions from the perspective of ground stress. The results indicate that the magnitude of the principal stress generally increases linearly with depth within the measurement range, with the maximum horizontal principal stress ranging from 3.48 to 20.76 MPa and a gradient of 0.0182 MPa/m with increasing depth, while the minimum horizontal principal stress ranges from 3.44 to 14.95 MPa with a gradient of 0.0130 MPa/m. The maximum horizontal principal stress azimuth in the area ranges from NE 43°to 89°, with an average azimuth of NE 75°. The tectonic action in the shallow crust is mainly horizontal, but with increasing depth, they gradually transition to vertical. Conclusion The triggering mechanism of the rock burst accident in the Longyun Coal Industry area on 20th October is primarily attributed to the vertical stress exceeding the horizontal principal stress, indicating a current extensional stress environment, especially when the tunnel orientation is parallel to the direction of maximum horizontal principal stress. It is suggested that the angle between the tunnel axis and the direction of maximum horizontal principal stress in the Longyun Coal Industry area should be between 60° and 90°, and that the tunnel roof can be designed as an arch-shaped roof to ensure the stability of the tunnel rock mass.

Background Hyperuricemia (HUA) caused by elevated serum uric acid (SUA) has been shown to be an independent risk factor for the development and progression of chronic kidney disease (CKD). However, there are few cohort studies on the correlation of SUA level with the development and progression of CKD in the elderly of China. Objective To explore the association of baseline SUA level and its changes with the risk of chronic kidney disease (CKD) and estimated glomerular filtration rate (eGFR) in the elderly in longevity areas of China. Methods Based on the Healthy Aging and Biomarkers Cohort Study (HABCS), a sub cohort of the Chinese Longitudinal Healthy Longevity Survey (CLHLS), the older adults who received physical examination and with biomedical indicators in 2012 and 2014 were selected as the study subjects from December 2021 to May 2022. The age, gender, blood pressure, blood lipids, blood glucose and other biomedical indicators were collected at baseline and follow-up period. Cox proportional hazards regression model was used to analyze the association of different SUA levels with the risk of CKD. Spearman rank correlation and generalized linear model analysis were used to analyze the association between baseline SUA level and baseline eGFR level and the linear correlation between changes in SUA level and eGFR changes in the elderly, respectively. Results A total of 981 subjects were included in the study, with the median age of 79 (70, 88) years, the prevalence of HUA of 6.8% (67/981), the cumulative follow-up of 2 029 person-years and the median follow-up of 2.05 years, including 179 new cases of CKD, the cumulative incidence of CKD during the follow-up was 18.2%〔95%CI (15.9%, 20.8%) 〕, and the incidence density was 88.22/1 000 person-years〔95%CI (76.24/1 000 person-years, 101.41/1 000 person-years) 〕. Cox proportional hazards regression analysis with SUA quartile grouping as the independent variable showed that compared with the lowest quartile group of baseline SUA level (Q1), the HR value for the risk of CKD in the highest quartile group of baseline SUA level (Q4) was 2.08〔95%CI (1.27, 3.41), P=0.004〕. Cox proportional hazards regression analysis with SUA level as the independent variable showed that, for every 10 μmol/L increase in baseline SUA level, the risk of CKD in the elderly increased by 4% (P

Necrolytic migratory erythema (NME) is usually associated with paraneoplastic syndrome caused by functional pancreatic neuroendocrine tumor (PNET). Accurate diagnosis and effective treatment of NET-related NME is challenging due to its rarity and lack of typical clinical symptoms and specific pathological manifestations. Here we report a rare case of PNET with NME as the initial manifestation. 68Ga-DOTA-TATE PET/MR was used to detect the primary pancreatic and metastatic liver tumors. Finally, the patient was diagnosed as PNET via liver biopsy. After four cycles of standard capecitabine plus temozolomide chemotherapy combined with long-acting octreotide, the patient’s skin lesions on both lower extremities improved only slightly, while tumors remained stable and unchanged in size. Then the patient was treated with surufatinib. Two months later, the skin lesions healed completely, and tumors responded significantly. This rare case suggests that surufatinib may be a promising therapy for patients with PNET-associated NME.

Buildings in service are severely affected by the complex environment with multiple coupled factors such as high temperatures, humidity, and inorganic salt attack. In this work, the mechanical properties of nano-SiO2-reinforced geopolymer composites (NSGPC) incorporated with varying dosages of polyvinyl alcohol (PVA) fibers were investigated under a complex environment. A simulated environmental chamber was employed to simulate the complex environment with relative humidity, temperature, and NaCl solution concentration of 100%, 45°C, and 5%, respectively. Fly ash/metakaolin geopolymer composites (GPCs) were fabricated by utilizing 1.5% nano-SiO2 by weight and five various dosages of PVA fibers by volume (0, 0.2, 0.4, 0.6, and 0.8%). The compressive strength, tensile strength, elastic modulus, and impact resistance of NSGPC eroded in a simulated environmental chamber for 60 days were determined. Then, the impact of the PVA fiber dosage on the mechanical properties of NSGPC under complex coupled environments was analyzed. In addition, scanning electron microscopy (SEM) was employed to evaluate and analyze the microstructural behavior of NSGPC under complex environments. Results indicated that the compressive strength, tensile strength, elastic modulus, and impact resistance of NSGPC increased with increasing PVA fiber to 0.6% and then decreased with a continuous increase to 0.8% but remained higher than those of the reference specimen. NSGPC exhibited the best performance at a PVA fiber dosage of 0.6%, which increased by 13.3, 12.0, 17.2, and 522%, respectively. The outcomes of SEM analysis indicated that the usage of PVA fiber and NS remarkably improved the mechanical properties and microstructural behavior of GPC by making the inner structure of GPCs more robust and compact under a complex environment. The outcomes of this work can provide theoretical guidance for buildings serving under a complex environment.

The geopolymer mortar (GPM) prepared from industrial by-products and alkali activation solution (AAS) is one of the hot spots of current building materials. As a feasible alternative to natural river sand, manufactured sand (MS) alleviates the global ecological pressure. In this study, MS was used for fine aggregate. Sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) solution were used as AAS. Metakaolin (MK) and fly ash (FA) were used as the precursor to prepare MK-FA-based GPM with MS (MS-GPM), which was of great significance for saving non-renewable resources, mitigating the greenhouse effect, and recycling waste. Numerous studies were conducted to explore the effect of sand–precursor ratio (r sp) on mechanical and durability characteristics of MS-GPM. Relationships between compressive strength and tensile or flexural strength were established by linear fitting equation. Finally, analysis of variance (ANOVA) was used to systematically calculate the effect of r sp on performance. The results indicated that the mechanical strength and impermeability of MS-GPM decreased and crack resistance increased with r sp from 1 to 5. The strength of MS-GPM was the best when r sp was 1. With the increase of r sp, the proportion of MS in MS-GPM increases, and the relative cementitious material decreases, which has an adverse impact on mechanical properties and impermeability. Linear fitting revealed that the compressive strength of MS-GPM was closely related to tensile strength and flexural strength. ANOVA results indicated that r sp in the range of 1–5 had great effects on the performance of MS-GPM. The aim of this article is to further promote the possibility of applying MS-GPM in practical engineering by designing reasonable r sp.

Some disinfection by-products (DBPs) in drinking water present a potential safety concern. This study focuses on the elements influencing DBPs formation. A total of 120 water samples were collected from 10 different drinking water facilities spanning 5 counties within Huzhou, Zhejiang Province, China. Concentrations of trihalomethanes (THMs) and haloacetic acids (HAAs) were observed to be 14.5 and 27.4 μg/L, respectively, constituting 34 and 64% of the total DBPs. Seasonal fluctuations demonstrated that HAAs, THMs, halonitromethanes (HNMs), and haloacetonitriles (HANs) followed a similar pattern with higher levels in summer or autumn compared to spring. Importantly, the concentrations of HAAs and THMs were markedly higher in Taihu-sourced water compared to other sources. Geographically, Nanxun exhibited the highest levels of total DBPs, HAAs, and THMs, while Deqing and Changxing demonstrated significantly lower levels. Correlation studies between water quality parameters and DBPs revealed that factors such as chloride content, temperature, and residual chlorine positively influenced DBPs formation, whereas turbidity negatively affected it. Principal component analysis suggested similar formation processes for HANs, haloketones (HKs), HNMs, and THMs. Factors such as temperature, chemical oxygen demand (COD), and residual chlorine were identified as significant contributors to the prevalence of HAAs. HIGHLIGHTS Twenty classes of DBPs and eight kinds of water quality parameters were monitored.; The impacts of water source and season were different between DBP species.; The temperature and COD played important roles in HAAs occurrence.;

The incidence of prostate cancer （PCa） has been increased year by year， mainly occurring in elderly men. Currently， prostate-specific antigen （PSA） is still used as a marker for diagnosing PCa in clinical practice. However， the accuracy and sensitivity of PSA remain relatively low. Identifying more clinical detection parameters for assisting diagnosis becomes a research hotspot. Most of patients with malignant tumors are in a hypercoagulable state. Studies have found that plasma fibrinogen （FIB） is differentially expressed in PCa. In addition， FIB has been considered as a potential tumor-promoting factor in PCa. In this article， the discovery， biological structure， physiological function， pathological changes （inflammation and tumor） and functions of plasma FIB， especially the relationship between plasma FIB and PCa， were systematically reviewed， aiming to provide reference for relevant clinical research.

In wireless communication technology, wireless sensor networks usually need to collect and process information in very harsh environment. Therefore, accurate positioning of sensors becomes the key to wireless communication technology. In this study, Davidon–Fletcher–Powell (DFP) algorithm was combined with particle swarm optimization (PSO) to reduce the influence of distance estimation error on positioning accuracy by using the characteristics of PSO iterative optimization. From the experimental results, among the average precision (AP) values of DFP, PSO, and PSO-DFP algorithms, the AP value of PSO-DFP was 0.9972. In the analysis of node positioning error, the maximum node positioning error of PSO-DFP was only about 21 mm. The results showed that the PSO-DFP algorithm had better performance, and the average positioning error of the algorithm was inversely proportional to the proportion of anchor nodes, node communication radius, and node density. In conclusion, the wireless sensor node location algorithm combined with PSO-DFP has a better location effect and higher stability than the traditional location algorithm.

Cognitive behavioral therapy for insomnia (CBT ⁃ I) boasts convincing evidence from randomized controlled clinical trials, yet its practical application encounters substantial barriers. This paper analyzes the key techniques and challenges of CBT ⁃I, proposing the following workflow improvements to enhance its clinical application and benefit more insomnia patients.

Promoting agricultural international trade to agricultural ecological environment governance is an important step in the process of agricultural modernization, which is helpful to realize the rural revitalization strategy and ensure national food security. In this essay, Henan Province was taken as an example to evaluate the performance of agricultural eco-environmental governance in Henan Province from 2013 to 2021. In this study, entropy weight -TOPSIS model was used to select 11 indicators from four dimensions of agricultural production conditions, agricultural non-point source pollution, agricultural output level and the intensity of ecological environment governance to construct the performance evaluation index system of agricultural ecological environment governance. TOPSIS model results showed that agricultural non-point source pollution had the greatest impact on agricultural eco-environmental performance evaluation in Henan Province. The performance score of agricultural eco-environmental governance in Henan Province showed a V-shaped distribution, which decreased year by year from 2013 to 2016 and increased year by year from 2017 to 2021.

As a control and regulating project, the hydropower station in the Yigongzangbu basin of Tibet plays a vital role in meeting the electricity demand of the Tibetan power grid. Identifying this hydropower station’s present-day in-situ stress environment and understanding the characteristics of in-situ stress distribution at critical locations such as underground plants and diversion tunnels are essential to ensure its engineering safety. Based on the tectonic and geological background and rock conditions of the project area, we carried out hydraulic fracturing in-situ stress measurements by placing boreholes and obtained in-situ stress data from 4 measurement points (8 boreholes). A finite element three-dimensional geological model was established according to the existing geological conditions. The measured stress state revealed the loading conditions, and the inverse analysis of the stress field in the engineering area was made. The maximum horizontal principal stress ranges from 4.17 to 16.93 MPa in the 2D test and 14.2 to 16.23 MPa in the 3D test. The maximum horizontal principal stress orientation is NE 38°to NE 47°, and the NE direction dominates the present-day tectonic stress field. In the 2995-meter elevation horizontal plane of the underground plant area of the power station, the stress values of σ1, σ2, and σ3 range from 11.70 to 12.12 MPa, 9.81 to 10.74 MPa, and 5.22 to 6.85 MPa, respectively. The maximum principal stress value of σ1, σ2, and σ3 along the diversion tunnel range from 11.8 to 14.05 MPa, 10.13 to 12.83 MPa, and 4.56 to 8.49 MPa, respectively. The axis direction of this hydropower station’s underground plant and the diversion tunnel’s axis direction intersect at a slight angle with the direction of the measured maximum principal stress, and the ground stress field is favorable to the stability of the project cavern. It is necessary to consider the actual geological conditions and adopt suitable tunnel construction technology in the later construction process. The construction monitoring should also be strengthened to ensure the project’s safe construction.

Fano resonance from photonic crystal nanobeam cavity (PCNC) is important building block for large-scale photonic integrated circuits (PICs) to enable photonic switches and sensors with superior characteristics. Nevertheless, most state-of-the-art demonstrations rely on electron beam lithography (EBL) and operate in dielectric mode. Hence, we theoretically, numerically and experimentally present the characteristics of Fano resonance from optical interference between the discrete state of air-mode PCNC and the continuum mode of side-coupled line-defect waveguide with partially transmitting element (PTE) using deep ultraviolet (DUV) lithography for the first time. Experimentally high average Q-factor of ∼1.58 × 104 is achieved for 30 measured devices, which indicates the feasibility of mass manufacture of high-Q Fano resonance from air-mode PTE-PCNC. Additionally, the thermo-optic bi-stability and thermal tuning characterizations of the proposed device are discussed. This work will contribute to building ultra-compact lab-on-chip resonance-based photonic components.

The existing wireless communication technologies in wireless blind spot coverage have challenges in non-line-of-sight scenarios in coal mines. In order to solve the above problems, a solution approach is proposed to introduce intelligent reflecting surface (IRS) into the wireless communication system in coal mines to achieve blind compensation of wireless signal coverage. This paper analyzes the causes of wireless coverage blind spots in coal mines, including closed mine environments characteristics, common non-line-of-sight scenarios, and safety constraints on transmission power and antenna settings. However, traditional wireless coverage blind spot solutions for underground coal mines have limitations in hardware deployment, maintenance costs, and technical implementation. They cannot truly meet safe and efficient communication needs of specific mining scenarios. IRS has significant performance advantages in achieving coverage blind compensation due to its low cost, low power consumption, easy deployment, and scalability. This paper introduces IRS technology from three aspects: hardware structure, auxiliary channel model and typical application scenarios (precise positioning, signal and energy simultaneous transmission, UAV communication, edge computing and physical layer security). This paper proposes the use of IRS technology to optimize underground wireless blind spot coverage. By deploying IRS reasonably in coal mines, it reduces the absorption and scattering of main signal components by walls, and utilizes the adjustable reflection characteristics of IRS to optimize signal propagation. It significantly improves signal strength and coverage range. The future research directions of IRS technology in underground wireless communication in coal mines are pointed out. The directions include energy management of IRS-aided coverage and blind compensation systems, IRS-aided underground communication based on artificial intelligence, application of new IRS technology, and flexible deployment of IRS.

With the increase of the penetration rate of distributed generation (DG), lack of flexibility of distribution network has become increasingly prominent. This paper focuses on electric energy router (EER), and analyzes its impact on the flexibility of distribution network. First, the index of the transfer flexibility of distribution network is proposed to represent one aspect of distribution network flexibility. Then, the linear model of the EER and its related constraints are analyzed, and an optimization model of the transfer flexibility of the active distribution network with the EER model is constructed. Finally, based on the 94-bus alternating current distribution network, different scenarios are designed to analyze and compare the effects of different DG operation control modes and different parameters of EER on the transfer flexibility of distribution network. The effectiveness of EER in improving the transfer flexibility of distribution network is verified.

The rapid development of information and artificial intelligence technology has brought new opportunities for innovation and transformation in higher education, leading to innovative applications of data-driven-assisted teaching decisions. This paper analyzes the equilibrium point in predicting students’ performance using nonlinear differential equations, solves the expected value of students’ performance, and constructs a prediction model for students’ innovation and entrepreneurship performance. Student achievement data and characteristics are preprocessed to improve the accuracy of the prediction model. Based on Pearson’s coefficient, students’ innovation and entrepreneurship achievement are significantly correlated with teaching ability (P

We propose a tunable all-dielectric zero-index metamaterial based on phase change material. By constructing the alternating rod structure with phase change material and silica material, the zero-refractive index characteristic is realized. In order to verify the equivalent zero-index characteristic, we calculated the electromagnetic field distribution at center frequency. Based on phase invariance, it was found that this kind of metamaterial can achieve equivalent zero refractive index characteristics. To further achieve the polarization-insensitive zero refractive index, we propose a metamaterial structure based on the fishing nets structure. Based on the S-parameter inversion algorithm, the equivalent dielectric constant, equivalent permeability, equivalent impedance, and equivalent refractive index of the metamaterial were extracted. Based on the extracted equivalent parameters and the corresponding electromagnetic field distribution, the designed all-dielectric metamaterial has the tunable equivalent zero refractive index characteristic.

Curcumin is an isolated phytopolyphenol pigment found in the Curcuma longa, commonly known as turmeric, with various pharmacological properties. It has many effects, including anti-tumour, anti-inflammatory, anti-bacterial, anti-oxidation, and hypoglycemic properties. However, due to its oral bioavailability, the use of the drug in the clinical environment is limited. Moreover, curcumin’s low bioavailability is attributed to its insoluble nature, poor permeability, and inhibition of P-glycoprotein efflux and enzyme metabolism. Several new dosage forms of curcumin have been developed based on its physical properties to improve oral administration. However, the curcumin oral administration system still needs to be improved from the perspective of both research and clinical applications.

To investigate the effects of wet–heat–salt coupling environment (WHSCE) and the content of polyvinyl alcohol (PVA) fibers on the durability of cementitious composites (CC), a series of durability tests were carried out. In this study, the salt concentration in the WHSCE was set to 5%, the temperature at 50°C, and the relative humidity at 100%. Six different contents of PVA fibers were set up in the test for exploring their effects on the durability (impermeability, chloride ion penetration resistance, freeze–thaw resistance, and chloride salt erosion resistance under dry and wet cycle conditions) of CC. The results showed that durability of CC under the WHSCE was enhanced regardless of the content of PVA fibers added. At the PVA fiber amount of 1.2%, the impermeability pressure, electric flux, mass loss rate, compressive strength loss rate, and compressive strength corrosion resistance coefficient under the WHSCE reached the optimal values. This indicated that the durability of CC was most favorable when the amount of PVA fibers was 1.2% since many engineering structures are subject to erosion by various factors in the ocean, which can inevitably affect the service life of the purchase. In this study, the effect of PVA fiber content on the durability of CC in complex environment is studied, which provides experimental data and analytical ideas for improving engineering located in the ocean, hoping to provide a theoretical basis for their subsequent application in practical engineering.

Recently, water injection-induced earthquakes caused by faulting instability have become a prominent geological safety issue for safely exploiting deep geothermal resources. This study investigates whether the future large-scale development of deep geothermal resources in the Gaoyang uplift will destabilize buried faults. There has a great amount of karst thermal reservoir in the Gaoyang low uplift, Hebei province. To find out whether the large-scale deep geothermal exploitation in the future will induce faults distributed in and around Gaoyang geothermal reservoir to become unstable, firstly, we calculate the initial stable state of the main buried faults based on Mohr-Coulomb criteria using the comprehensive in-situ stress field of North China; then, under Hsieh and Bredehoeft hydrological model, we calculate the possible excess pore pressure caused by water injection for 10~40 years at representative geothermal wells; subsequently, combing this perturbation with the initial stable state, we obtain the fault slip potential of the main buried faults from 2022 to 2062 based on a probabilistic approach; ultimately, we discuss the impact on the changes of fault slip potential due to varying angles between the maximum horizontal principal stress and the fault orientation. The main conclusions of this work can be drawn as follows. With the injection rate of 170 m3/h, the maximum excess pore pressure caused by a single geothermal well does not surpass 11 MPa, and it obeys a power decrease distribution with increasing distance from the center of the injection well; its influence scope is no more than 8 km. Continuous water injection strongly changes the stability of those buried faults distributed 2 km within the geothermal wells, and fault-slip potentials of some segmental faults even exceed 85%, corresponding to high unstable risk. Under 50 years of water injection at an injection well, the fault-slip potential of faults with different strikes within 2 km from the injection well increases rapidly with the declining angle among its orientation and the regional maximum horizontal principal stress. This paper's study methodology and associated findings can offer geoscientific justification for the safe exploration and exploitation of deep geothermal resources domestically and internationally. This study can provide a method reference for the location of injection wells and the selection of faults in different orientations in geothermal fields at home and abroad, thus promoting the safe and efficient development and utilization of geothermal resources.

Volume and pre-charge gas pressure are the key parameters of the gas-charged accumulator, which are of great influence on its dynamic performance(the output performance of pressure and flow under working conditions). The calculation and selection of a certain type of aircraft rudder surface emergency gas accumulator is taken as an example, based on the hydraulic component library in the Hypneu simulation software, combined with the main design parameters of this type of aircraft hydraulic system and the working principle of the emergency accumulator, the simulation model of the actuation of the accumulator is established. The test points are set in Hypneu to record the simulation curve, and the influence of the key parameters of the gas-filled accumulator on its dynamic performance is explored by analyzing the simulation curve. The theoretical calculation and simulation analysis are combined to propose a set of accumulator parameter selection method, and the selection method is verified by experiments. The results show that the greater of the pre-charge gas pressure of the accumulator is, the smaller the effective volume output by the initial accumulator is, and the reduction of the pre-charge gas pressure can increase the effective volume, and reduce the output pressure of the accumulator at the same time. The experimental results are close to the simulation results, and the accumulator selected by this method can meet the actuation requirements.

Objective To evaluate the prognosis and immunotherapy response of patients with bladder cancer by constructing a risk-score model of cellular senescence-related signature (SRS), as well as to explore the clinical application value of SRS in bladder cancer. Methods Senescence genes were screened from TCGA-BLCA, and cellular SRS genes were screened according to LASSO regression. A bladder cancer risk-score model was constructed based on the SRS genes to analyze the survival difference and model-fit degree of TCGA-BLCA high- and low-risk groups. Univariable and multivariable Cox regression was used to analyze the prognostic risk factors of bladder cancer. Overall survival differences of high- and low-risk groups in GEO-BLCA database were verified, and variations in immunotherapy responses were analyzed in IMvigor210 databases. According to the result of β-gal chromogenic reaction in bladder cancer and normal paracancer tissues, the existence of cell senescence was determined. Results Eight marker genes were screened, and patients were divided into high- and low-risk groups according to the median risk score constructed by the marker genes. The 5-year survival rate of high risk group was lower than that of low risk group (training and validation sets P < 0.05). The area under the ROC curve of TCGA-BLCA in 1-, 3-, and 5-year were 0.657, 0.660, and 0.688, and those for GSE13507 were 0.665, 0.665, and 0.613, respectively. SRS risk score can be used as an independent risk factor for the prognosis of patients with bladder cancer. The SRS risk score in the response group was lower than that in the non-response group during bladder cancer immunotherapy (P < 0.05). The β-gal staining of bladder cancer tissue was positive, but the β-gal staining of adjacent normal tissue was negative. Conclusion Cell senescence occurs in bladder cancer tissues. SRS risk score can predict the clinical prognosis of patients with bladder cancer, and patients with low score can benefit from immunotherapy. SRS is a reliable biomarker for the prognosis and immunotherapy response of bladder cancer.

Coal gangue slurry backfilling is an important technical means of harmless large-scale disposal of gangue under low disturbance conditions, and is one of the important ways to achieve green coal mining, in line with the national green development concept. But for the preparation, long-distance transportation, and goaf disposal of the slurry backfilling material and other aspects of the research is still imperfection, part of the problem of research is still blank, seriously restricting the development of slurry backfilling technology in the field of coal gangue solid waste disposal. Through recent years, coal gangue slurry backfilling in the basic theory and key technology has made a lot of results. The article systematically composes a variety of coal gangue backfilling solid waste disposal technology and its development history, summarizes its applicability and advantages and disadvantages, elaborates the technical background and scientific connotation of the birth of slurry backfilling, and clarifies the key technology and process principle of slurry backfilling. From the perspective of large-scale promotion and application, the three key scientific issues of precise preparation and rheological characteristics of slurry backfilling materials, long-distance pipeline transport characteristics of gangue slurry, spatial dynamic evolution of goaf and the law of slurry intervention have been summarized, and research on precise slurry production technology, pipeline transport technology, and multi-position backfilling technology of slurry has been focused around the above key scientific issues. The rheological characteristics of gangue slurry under multi-factor coupling conditions are analyzed, the mechanism of gangue slurry formation is revealed, the precise preparation model of gangue slurry is constructed, the determination method of key parameters of gangue slurry pipeline transportation is proposed, and the flow and diffusion laws of three forms of slurry-high, low and adjacent are summarized, which in turn to guide the slurry backfilling engineering practice. Based on the above research, the shortcomings and the focus of the future research of the current research on slurry backfilling technology are analyzed, and the development trend of coal gangue slurry backfilling technology under the background of Dual Carbon has prospected, and the following three directions are considered to be the focus of future research: ①mineralized CO2 preparation of carbon-negative slurry technology; ②slurry reconstruction rock layer technology based on MICP technology; ③slurry replacement fluidized mining technology for hard-to-mine coal bodies.

Radiation-related teeth damage is a common complication in nasopharyngeal carcinoma (NPC) patients undergoing radiotherapy (RT) that seriously affects their oral health-related quality of life (OHRQoL). However, few studies have focused on protecting teeth function. This study aimed to calculate dental dose limits based on OHRQoL. Analysis was performed on 96 NPC patients who received RT (all received routine pre-radiotherapy dental interventions in our department). Based on the General Oral Health Assessment Index (GOHAI), OHRQoL was assigned into poor (

The anatomical site of osteosarcoma is generally complex. Hence, it is difficult to accurately remove osteosarcoma and retain important nerves and blood vessels around the tumor, as well as repair and reconstruct bone defects after osteosarcoma resection. 3D printing technology can "tailor" the "bone defect" after removing the irregular osteosarcoma to achieve a good therapeutic effect of limb reconstruction. This study reviews the application of 3D printing technology in the preoperative, intraoperative, and postoperative reconstruction of osteosarcoma and bone tissue engineering scaffolds. Thus, this study systematically analyzes the advantages and suggestions of 3D printing technology based on the characteristics of 3D printing to put forward references for the accurate treatments of osteosarcoma in the future.

ObjectiveTo explore the risk factors of stroke， and to provide reference for the prevention and health management of stroke.MethodsFrom February 2022 to March 2022， four community residents over 60 years old with stroke in Shanghai were randomly selected as the case group （n=100）， and non-stroke residents were selected as the control group （n=100）. The survey was in the form of questionnaires to record and compare the age， body mass index （BMI）， blood lipids， blood pressure-related indicators， family history of other diseases， living habits， mood and sleep conditions of all subjects. The value of predicting the incidence of stroke among the elderly in Shanghai community was analyzed by receiver operating characteristic （ROC）， and the influencing factors of stroke were analyzed by logistic model.ResultsBMI， hypertension， heart disease， diabetes， transient ischemic attack （TIA）， dyslipidemia， family history of stroke， smoking， lack of exercise or only light physical labor， SBP， DBP， TG levels were significantly higher in the case group （P

As an important radioactive tracer, 14C has been widely used in many fields, such as biomedicine, agriculture, geology, environment etc, due to its ability to reveal the distribution, metabolic mechanism and migration path of the substances. In recent years, the demand for 14C-labeled compounds has continued to grow, and its application field has been expanded. This paper summarizes the sources, preparation, separation and purification methods of 14C isotopes. Meanwhile, this paper reviews the preparation, structural identification and application in related research fields of 14C labeled compounds, and emphatically discussed the development status and trend of 14C isotope separation and purification technology. It is hoped that recyclable utilization of 14C resources can be realized with solving the pollution of 14C emissions, which will further promote the development of 14C application.

In this study, polyvinyl alcohol (PVA) fibers and nanoparticles were incorporated to enhance the durability of geopolymer mortar (GM) with metakaolin (MK) and fly ash (FA). The dosage of nano-SiO2 (NS) was 0–2.5% and that of PVA fiber was 0–1.2%. The durability of GM includes resistance to chloride ion penetration, freeze–thaw cycles, and sulfate erosion. Compared with the single BP neural network (BPNN) model, a particle swarm optimized BPNN (PSO-BPNN) model was utilized to predict the resistance to chloride ion penetration, freeze–thaw cycles, and sulfate erosion of GMs with different dosages of nanoparticles and PVA fibers. In the model, the dosage of NS, PVA fiber, FA, and MK were used as input layers, and the durability parameters of electric flux, mass loss, and compressive strength loss of GMs were used as output layers. The result exhibits that the root mean square errors (RMSEs) of BPNN for resistance to chloride ion penetration, freeze–thaw cycles, and sulfate erosion of GM mixed with nanoparticles and PVA fibers are 145.39, 6.43, and 2.19, whereas RMSEs obtained from PSO-BPNN are 76.33, 2.87, and 1.03, respectively. The NN optimized by particle swarm algorithm has better prediction accuracy. The PSO-BPNN can be utilized for estimating durability of GM reinforced by NS and PVA fiber, which can provide a guide for the proportion design of GM with PVA fiber and NS as well as for the engineering practice in the future.

Underwater optical communication is a new and feasible underwater communication technology, which has developed rapidly in recent years. To build a high-performance and practical underwater optical communication system, it is necessary to consider and optimize the design from the device to the system, from the internal modulation to the external environment. This paper summarizes the current problems of underwater optical communication from the aspects of underwater optical communication system transmitter and receiver, modulation format and underwater channel. The paper also classifies and summarizes the three key technologies of improving underwater optical communication distance, communication rate and communication stability, and gives the possible solutions. It provides reference for the follow-up system design and experimental research.

With the continuous increase of coal seam mining depth, the coal mine production faced with complex water inrush mechanism and changeable main controlling factors, which makes the prediction of floor water inrush more difficult. In order to accurately predict the risk of floor water inrush, the vulnerability index method was used to obtain the risk weight of floor water inrush for each sub-factor, and the analytic hierarchy process(AHP) was used to divide the risk threshold of floor water inrush, so as to establish coal seam floor water inrush prediction model. We analyzed the geological and hydro-geological data of Henan Longmen Coal Industry Changcun Coal Mine from the three aspects of water inrush sources, water inrush channels and aquifers, the influencing factors of floor water inrush are divided into eight factors: aquifer water pressure, water output, grouting volume, fault similarity dimension, fault dip, fault strike, fault drop and effective aquifer thickness. Based on eight sub-factors, the risk of floor water inrush is divided into five areas: safe area [0.25, 0.32), relatively safe area [0.32, 0.44), the more dangerous area [0.44, 0.56), the dangerous area [0.56, 0.70), and the extremely dangerous area [0.70, 0.85]. Finally, the vulnerability index method evaluation model based on AHP was established. Compared with the traditional water inrush coefficient method, the evaluation results of the vulnerability index method based on AHP have better accuracy, and the division is more refined and reasonable, which provides a scientific evaluation method and theoretical basis for the prediction of mine water hazards.

The accuracy of traditional milling force prediction model is low, and it is difficult to provide effective support for the reasonable selection of process parameters in practical production, by synthetically considering the equivalent turning force model of working angle, cutting edge arc and radius of tool tip arc, in this model, the actual turning tool is equivalent to the ideal turning tool model to identify the material constant, the chip flow angle and the average friction angle in the material constitutive equation, according to the oblique cutting model, the shear stress on the main shear plane and the F0 vector of the unit cutting force at different cutting speeds are calculated, thus the instantaneous cutting force on the front face of the end mill can be calculated, the three-dimensional cutting force of end mill in X-Y-Z coordinate system is obtained by coordinate transformation. The prediction of the cutting force model is verified by simulation and experiment.