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The frequency regulation capability of wind turbines is insufficient to satisfy the needs of grid frequency regulation. The characteristics of energy storage， such as flexible control， substantial throughput capacity， and rapid response rates， can effectively complement wind turbine limitations. Thereby， these facets advocate for incorporating an integrated wind-and-storage system in the practice of grid frequency control. This paper delves into the principles and control strategies associated with the participation of wind turbines and energy storage in the regulation of power system frequency. It outlines the principles and features of energy storage participating in frequency regulation， as well as models for frequency control and the control strategies. Moreover， the paper scrutinizes the characteristics and effects of different and hybrid energy storage systems. Subsequently， it elucidates the principles of frequency control for wind turbines and various control strategies， classifying the control modes of wind turbines into： variable-pitch control， rotor kinetic energy control， and unified control. In conclusion， the current state of advancements and prospects in this field are summarized and envisioned.

AC submarine cable is an important component in AC transmission system of offshore wind farms. However, the issue of charging current limits its application in offshore wind power with long-distance and large-capacity. Taking HYJQF41-F290/500 kV single-core AC submarine cable as an example, the overvoltage distribution along the cable in different working conditions is analyzed, considering the long-distance and high-voltage transmission. The simulation model of the cable is established and its parameters are corrected firstly. According to the different compensation degrees of the shunt reactor, the capacity of the shunt reactor under the configuration scheme of single-end compensation and two-end compensation calculated out. Finally, based on the single-phase grounding fault, the closing and opening conditions in the high-voltage and long-distance wind farm models, and the distribution law of overvoltage along the submarine cable under different reactive power compensation schemes is tested by simulation. The results show that the maximum overvoltage of submarine cables appears in different positions with different compensation schemes. Based on this, the selection methods for high-voltage submarine cable and overvoltage in insulation level design of substation equipment are given out under different compensation schemes, which have certain guiding significance for engineering practice.

The high geothermal environments encountered in deep mineral mining induce thermal damage to rocks, which can trigger geotechnical disasters in deep engineering projects. Therefore, exploring the degradation characteristics of rock mechanical properties and the damage evolution laws after high-temperature exposure is of significant importance for rock engineering in deep high-geothermal environments. By subjecting granite to the temperature range from ambient to 1200 ℃ and conducting macro-microscopic studies using optical microscopy, the degradation characteristics of Young's modulus and compressive strength in granite samples post various high-temperature treatments were investigated. Additionally, an analysis was performed on the internal cracks and damage evolution in thermally damaged granite from a microscopic perspective. The experimental results demonstrate that high-temperature treatments significantly reduce the mechanical properties of granite. The granite's compressive strength and Young's modulus decrease with increasing treatment temperatures, and the extent of crack development increases with temperature. The mechanic cal properties of granite are highly correlated with the development of internal crack structures. There is a power function relationship between the crack density and compressive strength in granite after different temperature treatments, indicating that crack density can effectively reflect the extent of thermal damage in granite.

In this study, experimental tests were conducted on sandstone specimens to study the influence of seawater corrosion on their physical and mechanical properties as well as failure behavior.Different concentrations of simulated seawater solutions were prepared based on seawater sampling data from the vicinity of the Shenzhen cross-harbor tunnel.Sandstone specimens were first treated with corrosion immersion in these solutions for different times before they were subjected to uniaxial compression tests.The acoustic emission and scanning electron microscope(SEM)techniques were employed to investigate damage and microstructural evolutions of the corroded sandstone.The results show that as the concentration of corrosive solution increases, the surface of sandstone specimens peel off earlier, the area is larger, and there is a slight increase in specimen density.The peak stress and elastic modulus both decrease with increasing corrosion time, but the magnitude and rate of decrease are different.With the increase of corrosion time and concentration, the active period of acoustic emission events increased in all sandstone specimens, except for the ones in the high concentration group, where the active period of acoustic emission events was shortened after 45 d of corrosion.SEM results show that with increase of corrosion time and concentration, the internal microdefects in the sandstone specimens progressively developed, and the microstructures gradually loosened.Furthermore, the area of honeycomb corrosion area increased in size and the area of white crystallization of salt ions gradually expanded.

[Objective] This study intends to explore the main source of sediment and the evolution of erosion and sediment yield in Sanggan River Basin. [Methods] A typical warping dam in Gaoqiang Township, Yangyuan County was selected as the research object. The composite fingerprint identification technology was used to determine nine fingerprint factors, including soil particle size, SOC, TN, radionuclide (137Cs) and low-frequency magnetic susceptibility, of sediment and its source areas. The evolution patterns of erosion and sediment production in different sedimentation stages of sediment source areas and dam controlled small watersheds were studied. [Results] (1) The average content of 137Cs in sediment was relatively low, and it was not significantly different from that of gully wall soil, but it was extremely significantly lower than that of forest-grasslands and croplands soil (p croplands (15.36%±8.46%) > forest-grasslands (1.96%±0.33%). (3) In the evolution of erosion and sediment yield, gully wall was the main sediment contribution area for a long time, forest-grasslands had weak response to erosive rainfall, and the sediment contribution rate of croplands increased significantly when extreme rainstorm occurred. [Conclusion] Overall, the 137Cs tracing technique was suitable for identifying the main sediment source in the small basin, and the composite fingerprint technique was better at identifying multiple sediment sources. The collapse of gully walls caused by gully erosion was the main cause of severe soil erosion in the Sanggan River Basin.

Since the fault vibration data collected in real engineering may be accompanied by noise，traditional diagnostic models are difficult to identify fault categories，to address this problem，a rolling bearing fault diagnosis research method based on channel and spatial reconstruction and progressive convolutional neural networks （CSRP-CNN） was proposed.The model utilizes channel and spatial reconstruction convolution （CSConv） to reduce the redundant information of channels and space in fault features，and reduces the complexity and computation to improve the performance； using convolutional block attention module （CBAM），attention enhancement operation was carried out in the channel and spatial dimensions to make the model pay attention to important fault feature information； and progressive convolutional network structure was used in the shallow layer of the network，which will fuse the previous fault feature information fused with the current input to obtain richer feature information.The performance of CSRP-CNN was evaluated by two different datasets of Case Western Reserve University（CWRU）and machinery fault simulator magnum（MFS-MG）.After the noise and ablation tests，it is verified that CSRP-CNN has strong robustness and the effects of CSConv，CBAM and progressive convolutional neural network（PCNN） on the model noise immunity performance.

In order to better perform thermal hydraulic calculation and analysis of supercritical water reactor, based on the experimental data of supercritical water, the model training and predictive analysis of the heat transfer coefficient of supercritical water were carried out by using the support vector machine (SVM) algorithm. The changes in the prediction accuracy of the supercritical water heat transfer coefficient are analyzed by the changes of the regularization penalty parameter C, the slack variable epsilon and the Gaussian kernel function parameter gamma. The predicted value of the SVM model obtained after parameter optimization and the actual experimental test data are analyzed for data verification. The research results show that: the normalization of the data has a great influence on the prediction results. The slack variable has a relatively small influence on the accuracy change range of the predicted heat transfer coefficient. The change of gamma has the greatest impact on the accuracy of the heat transfer coefficient. Compared with the calculation results of traditional empirical formula methods, the trained algorithm model using SVM has smaller average error and standard deviations. Using the SVM trained algorithm model, the heat transfer coefficient of supercritical water can be effectively predicted and analyzed.

Objective: To analyze the clinical characteristics of alcohol-flame burns and the correlation with COVID-19 epidemic. Methods: A retrospective analysis was conducted on the medical records of 134 patients with alcohol-flame burns who were admitted to the Second People's Hospital of Chengdu City from January 2015 to December 2022. Demographics, time of first hospital visit, burn size, depth and site, month and place of burn, inhalation injury, surgical intervention, length of hospital stay, hospital costs were recorded annually. Data from the COVID-19 epidemic period (2020–2022) were compared to those from the non-epidemic period (2015–2019) for analysis. Results: The number of patients with alcohol-flame burns showed a consistent annual increase. During the epidemic period, the proportion of alcohol-flame burns among burn patients was significantly higher (2.43% ± 0.16%) than during the non-epidemic period (1.70% ± 0.15%) (P = 0.00). Alcohol-flame burns primarily affected adult men, occurring mainly in massage parlors and homes. The peak incidence was between May and August. Patients sought medical attention promptly, with a median time to first hospital visit of 2 h post-burn. Alcohol-flame burns mostly involved the trunk and upper extremities. Median total burn size was 7% TBSA, median full-thickness burn size was 1% TBSA. Over 20% of patients had combined inhalation injuries, and a similar proportion required surgical intervention. Alcohol burn patients had a median hospital stay of 14 days and incurred median medical costs of ¥16,600($2300). During the epidemic, the basic characteristics of patients with alcohol-flame burns did not change much. However, the time to first hospital visit was significantly shorter (2 h) during the epidemic period than non-epidemic period (3 h). Furthermore, alcohol-flame burn patients during the epidemic exhibited significantly larger total burn sizes, higher burn indices, and longer hospital stays compared to non-epidemic patients. The incidence of combined inhalation injuries was also significantly higher during the epidemic. Surgical requirements and medical costs were not significantly associated with the COVID-19 epidemic. Conclusion: Alcohol-flame burns exhibit distinct clinical characteristics, including severe injuries, prolonged hospital stays, and elevated costs, particularly in the context of the COVID-19 pandemic.

This study was conducted to test the effect of transition on the quality of life (QOL) among Chinese children who underwent liver transplantation more than 5 years earlier.

ObjectiveTo obtain the prevalence of sarcopenia in middle-aged and elderly people in Urumqi based on the 2020 updated based on the 2020 updated Consensus Report 2019 of Asian Working Group for Sarcopenia （AWGS2019）， and to further explore the association between sarcopenia and metabolic syndrome （MS）.MethodsA total of 1 438 middle-aged and elderly people （aged≥50 years） in Urumqi from July 2018 to January 2019 were selected as the research subjects. Data were collected by questionnaire survey， physical examination and laboratory test. Skeletal muscle mass，grip strength and 4 m walking speed were used to represent muscle mass， muscle strength and body function， respectively. Bioelectrical impedance analysis （BIA） was used to measure human body components. Based on the diagnostic criteria of sarcopenia recommended by AWGS2019， the prevalence of sarcopenia in people over 50 years old was obtained. Multivariate logistic regression model was used to explore the correlation between sarcopenia and MS in middle-aged and elderly people of different genders.ResultsThere were 194 patients with sarcopenia， with a prevalence of 13.49%. The prevalence was 15.56% in males and 12.12% in females. There was no significant difference in the prevalence of MS between male sarcopenia group （40.45%） and non-sarcopenia group （38.92%）， while the prevalence of MS in female sarcopenia group （39.04%） was higher than that in non-sarcopenia group （27.56%）. Multivariate logistic regression analysis showed that sarcopenia was a related factor of MS. Compared with non-sarcopenia， the risk of MS in male sarcopenia group was higher （OR=2.11，95%CI： 1.15‒3.88 ）.ConclusionSarcopenia increases the risk of MS in middle-aged and elderly people， with a greater risk in men. Fully understanding of sarcopenia is helpful to early identify high-risk groups of MS and prevent the occurrence of MS.

The movement and deposition of nanoparticles in supercritical carbon dioxide is a current international frontier subject. In the development of new nuclear reactors, using supercritical carbon dioxide Brayton cycle instead of traditional steam Rankine cycle can greatly improve the cycle efficiency, reduce equipment size and improve safety. In this new cycle, the movement and deposition of nanoparticles play a significant role under normal and abnormal operating conditions in nuclear power plants. Nanoparticles, due to their small particle size and higher relative surface energy, are more penetrable. When it under the thermophoresis force will emerge the thermophoresis deposition, causing collision and erosion to the pipeline. And it may be more destructive to supercritical devices or systems. To study the movement and deposition characteristics of nanoparticles in supercritical media, then further explore the factors affecting nanoparticles deposition, and find their qualitative and even quantitative relationship. This paper studies this problem from the aspects of particle size, wall temperature difference, incoming flow velocity, and so on to try to clarify the motion mechanism of nanoparticle deposition. In specific studies, stainless steel nanoparticles and supercritical carbon dioxide were selected as the objects, a 1 meter long horizontal straight pipe was taken as the flow geometric channel, based on the control single variable method, the factors affecting the thermophoresis deposition of nanoparticles were calculated and analyzed by Fluent software. According to the calculation to obtain the curve picture, the results show that the higher the fluid temperature, the greater the temperature gradient, and the greater the thermophoresis force on nanoparticles, which increases the dimensionless thermophoresis deposition velocity and the thermophoresis deposition rate. In addition, the increase of fluid temperature leads to the decrease of fluid viscosity and viscous resistance of particle movement, which also promotes the movement of particles and increases their deposition rate to a certain extent. In terms of particle size, the change of thermophoresis deposition rate caused by the change of particle size on a small scale (1100 nm) is more obvious than that on a large scale. With the increase of particle size, the thermophoresis force increases, but the increasing speed slows down. At the same time, the viscous resistance and lift increase in geometric multiples with the particle size. Under the combined action of these forces, the thermophoresis deposition efficiency decreases. The pipe diameter and flow velocity do not directly affect the thermophoresis deposition rate. The pipe diameter increases the average distance and reduces the thermophoresis gradient, while the flow velocity affects the heat transfer coefficient. In addition, the increase of external flow velocity enhances the carrying capacity of fluid, and nanoparticles are easier to be coerced out of the channel, thus reducing their thermophoresis deposition. Totally, for thermophoresis deposition, the temperature difference between the fluid and the wall is the most important factor affecting the deposition rate, and there is a positive correlation. The flow velocity, particle size, and pipe diameter are negatively correlated with deposition rate.

Objective： A surface-enhanced Raman spectroscopy (SERS) method was developed for non-targeted screening of PDE-5 inhibitors in health wine. Methods： An appropriate SERS base of colloidal gold was prepared, and SERS analysis was conducted after the base was mixed with 78 kinds of PDE-5 inhibitors. The spectrogram screening database was established, and whether the matching degree was higher than 70% was used as the basis for judging whether the PDE-5 inhibitors were suspected to be added. Finally, the sensitivity and specificity of the method were investigated. Results: The best method of preparing PDE-5 inhibitors of SERS base was adding 1.0 mL 1% chlorauric acid and 0.7 mL 1% trisodium citrate into 98.3 mL ultrapure water. The lowest concentrations were sildenafil 0.05 mg/L, tadanafil 0.5 mg/L, thiosildenafil 0.05 mg/L and acevardenafil 0.1 mg/L, respectively. The qualitative results of simulated samples were consistent with those of HPLC-MS. Conclusion： In theory, this method can be used to screen non-targeted illegal addition of PDE-5 inhibitors in health wine.

Background: Warts are very common in military personnel, either at war or during peace times. However, little is known about the prevalence and natural course of warts in military recruits in China. Objective: To investigate the prevalence and natural course of warts in Chinese military recruits. Methods: In this cross-sectional study, the head, face, neck, hands, and feet of 3093 Chinese military recruits aged 16–25 years in Shanghai were examined for the presence of warts upon enlistment medical examinations. Questionnaires were distributed to collect the general information of the participants before the survey. All the patients were followed up by telephone interview for 11–20 months. Results: The prevalence rate of warts in Chinese military recruits was 2.49%. The diagnosis of most cases was common and plantar warts, which were usually less than 1 cm in diameter and with mild discomfort. Multivariate logistic regression analysis showed that smoking and sharing personal items with others were risk factors. Coming from southern China was a protective factor. Over 2/3 of patients recovered within 1 year and the type, number, and size of warts and treatment choice did not predict resolution.Study limitations and Conclusions This study demonstrated that warts had a relative lower morbidity and a higher spontaneous resolution rate in Chinese military recruits. The telephone interviews following the initial survey and the limitations of a cross-sectional study were the main drawbacks.

Improving the resilience of 3D-printed composites through material extrusion technology (MEX) is an ongoing challenge in order to meet the rigorous requirements of critical applications. The primary objective of this research was to enhance the impact resistance of 3D-printed composites by incorporating continuous hybrid fibers. Herein, continuous virgin carbon (1k) and Kevlar (130D and 200D) fibers were used with different weight and volume fractions as reinforcing fibers to produce hybrid and non-hybrid composites for impact resistance testing to obtain energy absorption with different impact energies: 20 J, 30 J, 40 J, and 50 J. Moreover, 0°/90° fiber orientations were used. Hybrid composites with combinations of PLA + CF + 130D KF and PLA + CF + 200D KF showed higher impact resistance, less damaged areas (71.45% to 90.486%), and higher energy absorption (5.52–11.64% more) behaviors compared to PLA + CF non-hybrids. CT scan images provided strong evidence to resist the fracture and breakage patterns, because the stiffness and elongation properties of the fibers acted together in the hybrids specimens. Furthermore, positive hybrid effects of the PLA + CF + KF hybrids also showed an ideal match of toughness and flexibility in order to resist the impacts. In the future, these hybrids will have the potential to replace the single type of composites in the fields of aerospace and automobiles.

The canopy of a fighter is the main source of electromagnetic scattering, and the achievement of its radar stealth is one of key technologies for developing a stealth fighter. The scattering sources mainly include the scattering in the cavity of the canopy (strong scattering source) and the local structural scattering (sub-strong scattering source). To satisfy the high stealth requirements, it is necessary to reduce the RCS of the sub-strong scattering source of the canopy. This paper studies the sub-strong scattering source of the canopy of a stealth fighter and proposes the canopy's sub-strong scattering source reduction and control measure by applying the basic radar stealth technology, the MLFMM and the RCS test.

Objective: To avoid young liquor as old liquor and realize the discrimination of Baijiu age. Methods: The near infrared transmission spectra of Baijiu samples were collected by near infrared spectrometer, and the synchronous and asynchronous two-dimensional correlation spectra of Baijiu samples were constructed with the wine age as the external disturbance. On this basis, the autocorrelation spectrum of each sample was extracted, and the age discrimination model of Baijiu was established by combining Markov distance method. Results: The wave band from 1 400 nm to 1 800 nm contained the effective information about the changes of Baijiu samples on age. The discrimination accuracy of model correction set was 93.3%, and that of prediction set was 92.0%. Conclusion: Two dimensional correlation spectrum combined with Mahalanobis distance method can effectively identify the age of Baijiu.

BackgroundIn the international fourth-generation nuclear power system, the lead-bismuth fast reactor is one of the most concerned technologies. However, insoluble particulate matter generated in the flow of liquid lead-bismuth alloys will collect locally in the flow channel and affect the operation of lead-bismuth fast reactors.PurposeThis study aims to find the motion deposition of particulate matter in the flow channel, understand its influence on the safe operation of small lead-bismuth fast reactors, and provide a reference for the safe design of lead-bismuth reactors.MethodsFirstly, based on the design scheme of 100 MWth small natural circulation lead cooled fast reactor SNCLFR-100, the particle deposition in the rod bundle channels that were divided into three types according to the relative position and wall conditions: triangle like channels, pentagon like channels and trapezoid like channels, was numerically simulated using ANSYS software, and the particle deposition movement was obtained. Then, the effects of particle type, particle size and particle velocity on particle deposition were obtained on the basis of grey correlation degree theory. Finally, the correlation degree of various factors affecting particle deposition rate was analyzed.ResultsThe results show that the particle deposition mainly occurs at the inlet stage,the surface of the inlet section is large area adhesion deposition,and the surface of the middle and rear sections is point-like deposition. With the increase of axial distance, the magnitude of turbulent kinetic energy is the main factor affecting the radial distribution of particulate matter. The increase of particle density and particle size will strengthen the deposition of particulate matter. The increase of particle velocity will reduce the particle deposition. The degree of influence on particle deposition is particle size>type> particle velocity.ConclusionsDuring the operation of lead-bismuth fast reactor, attention should be paid to the deposition of particles in the inlet section and to remove the particles with larger particle size.

The new power system is gradually evolving into a low inertia power system with high penetration of DC and new energy, and the inertia of the load side is gradually increasing. Asynchronous motors occupy a high proportion in the load side, and their frequency support function needs further research. In order to evaluate the equivalent inertia of asynchronous motor under inertial time scale, a small signal model of asynchronous motor is established in electromechanical transient state. The transfer function of asynchronous motor power consumption and system frequency deviation is inferred in this paper. At the same time, the effective inertia of asynchronous motor to power system is inferred and the time-varying characteristics of asynchronous motor to power grid is analyzed. According to the idea of frequency support capability in inertia response stage, the factors which affect inertia frequency response of asynchronous motor are analyzed. The equivalent inertia evaluation model of asynchronous motor is proposed to quantify the frequency support capacity of dynamic load. Finally, a simulation model is built on Matlab/Simulink and PSASP platform to verify the correctness and effectiveness of the evaluation model and method proposed in this paper.

Two parameters of ω0 and ωc in the active disturbance rejection controller are automatically optimized via the differential evolution algorithm in this paper. First, the design of the second-order linear active disturbance rejection control (LADRC) is studied, then, the program flow chart and parameters selection methods of the differential evolution algorithm are analyzed. Simulation tests show that for the second-order system with large nonlinear total disturbance, the differential evolution algorithm can obtain global optimal values of two parameters and the fitness function reaches the minimum value fastly under conditions of the accurate and inaccurate parameter b, thus the system can achieve the higher step response speed and tracking precision. Moreover, this algorithm is also marked with the faster convergence rate, higher efficiency and precision, which can provide a novel practical method for automatic tuning of LADRC parameters.

Under the new power system, the proportion of new energy and new entities continues to grow, new business users are diversified, and the power supply and demand sides exhibit a "double randomness" characteristic. Faced with such challenges, VPP (Virtual Power Plant), as source network load storage integrators that aggregate multiple distributed resources, provide the possibility for the supply-demand balance of the power system. At present, there is no mature operation mode for VPP in China, and they still rely mainly on aggregating load side resources for demand response. This article analyses Australia's participation, trading patterns, and profitability in the electricity market and ancillary services market, summarizes the profit and risk points of VPP in Australia, and proposes relevant suggestions for improving the business model of VPP and promoting their entry into the market in China based on the actual situation.

Introduction: For composite structures, delamination usually occurs at the interface. Ultrasonic guided waves have been widely used to detect the delamination. However, most researches focus on the measurement of the delamination length along the interface, and the measurement of the delamination thickness is less studied. Method: In this paper, based on the characteristic that the Stoneley wave only propagates along the interface, the reflection coefficient of interaction between Stoneley wave and delamination is used to measure the delamination thickness. The effects of delamination thickness and frequency on the reflection coefficient are investigated via dividing integral region and reciprocity theorem. Some experimental validations are carried out on two aluminum-steel bilayered composite plates with different delamination thickness. Results: It is found the reflection coefficient increases linearly at first, then its rate of increase slows down gradually, and finally becomes stable, in theory. And the experimental results can verify the theoretical relationship between the reflection coefficients and the delamination thickness. Conclusion: The variation of reflection coefficient provides a reference for the measurement of delamination thickness in Stoneley-wave-based non-destructive testing.

The long-term use of chemical insecticides to control stored-grain pests has caused problems like pest resistance and environment pollution. The article briefly introduces some common pests and the losses they caused. According to the requirements of green, environmental protection and safety of grain storage,the biological control technology for stored grain pests in the process of grain storage is discussed, and the research progress of the application of biological control technologies such as agents, pheromones, microbial source materials, plants and plant extracts were also introduced. We hope to develop ideas for the prevention of stored-grain pests, reduce or avoid the losses caused by the pests, provide reference for future research on stored-grain pests control technology.

The study of heat transfer coefficient of supercritical water plays an important role in improving the heat transfer efficiency of the reactor. Taking the supercritical natural circulation experimental bench as the research object, the effects of power, flow, pipe diameter and mainstream temperature on the heat transfer coefficient of supercritical water were studied. At the same time, the experimental data of Chen Yuzhou's supercritical water heat transfer coefficient was collected. Through the factorial design method, the influence of different factors and their interactions on the heat transfer coefficient of supercritical water is analyzed. Through the corresponding analysis method, the influencing factors of different levels of heat transfer coefficient are analyzed. It can be found: Except for the effects of flow rate, power, power- temperature and temperature, the influence of other factors on the natural circulation heat transfer coefficient of supercritical water is negligible. When the heat transfer coefficient is low, it is mainly affected by the pipe diameter. As the heat transfer coefficient is further increased, it is mainly affected by temperature and power. When the heat transfer coefficient is at a large level, the influence of the flow rate is the largest at this time.

The quality changes of paddy during storage are greatly affected by external conditions. The external factors include temperature, moisture, air proportion, pests and microorganisms, etc., especially under the condition of high temperature of stored grain and high moisture of rice, mold of rice grows faster, which leads to the reduction of rice quality. This paper introduced the effects of storage conditions on paddy quality and the harmfulness of pests and harmful microorganisms to paddy storage. The research on existing paddy storage and new grain storage technologies were further discussed. The development of new technologies such as grain storage, the use of CO2 to detect rice mold, and the development of natural antifungal agents has provided more effective technical guarantees for the safe storage of paddy in our country. However, some new technologies have higher requirements on grain silos and it is difficult to realize nationwide popularization.

Primary cilia are organelles present on most mammalian cells that sense environmental changes and transduce signaling, and they are the key coordinators of various signaling pathways during tissue development. This article reviews the progress of research on the distribution of primary cilia in tooth development and the related signaling pathways. A literature review shows that in odontogenesis, primary cilia play an important role in the mutual induction of the epithelium and mesenchyme; during the continuous proliferation and differentiation of cells, the distribution of primary cilia is temporally and spatially dependent. Although the reason for this distribution is still unclear, some experimental evidence indicates that this phenomenon is compatible with the function of cells and tissues in which primary cilia are distributed. Primary cilia are involved in the regulation of two important signaling pathways, Hedgehog and Wnt, in odontogenesis. Genes encoding cilia (such as Kif3a, Evc/Evc2 and Ift) can affect the development of teeth by regulating these two signaling pathways, and there is an interaction between the two signaling pathways. Deletion of related genes (such as Ofd1 and Bbs) can damage the transmission of upstream and downstream signals by damaging the structure or function of cilia, thereby causing various types of dental dysplasia, including small teeth, enamel hypoplasia, missing teeth, or craniofacial deformities.