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Objective To explore the application value of transnasal endoscopy combined with endovascular treatment in the operation of skull base tumors. Methods A retrospective analysis was conducted on the clinical data of 9 patients who underwent endoscopic transnasal resection of skull base tumors and received endovascular treatment at Tianjin Huanhu Hospital from January 2017 to July 2022. To observe the tumor resection and evaluate the postoperative efficacy of nasopharyngeal carcinoma according to the World Health Organization (WHO) solid tumor measurement standards. During the follow- up period, Glasgow Outcome Scale (GOS) was used to assess postoperative neurological function recovery, and record tumor recurrence or progression. Complications related to endovascular treatment, such as pseudoaneurysm, spontaneous cerebral hemorrhage and cerebral infarction, were also recorded. Results Among 9 patients, there were 4 patients confirmed donor artery or internal carotid artery (ICA) rupture by DSA before operation, one case underwent spring coil embolization before operation, one case had a carotid catheter sheath inserted in advance during operation, one case had successful hemostasis with spring coil embolization during operation, one case had successful hemostasis with covered stent implantation during operation, 4 cases had ICA rupture confirmed by DSA during operation, and one case had successful hemostasis with spring coil embolization after DSA confirmation of ICA rupture. The total resection rate was 8/9. During a follow - up of 32.00 (25.00, 48.50) months, all patients did not experience tumor recurrence or progression. At the last follow -up, the GOS scores were 4-5, indicating good recovery of neurological function. A patient with recurrent nasopharyngeal carcinoma who underwent immunotherapy had a recurrent pseudoaneurysm at the distal end of the ICA covered with a stent implanted in the petrous segment. Three months after the stent implantation, the patient underwent external carotid artery - radial artery - middle cerebral artery bypass surgery to successfully stop the bleeding without any postoperative complications. The remaining 8 patients did not experience complications such as spontaneous cerebral hemorrhage or pseudoaneurysm. All patients did not experience complications such as cerebral infarction. Conclusions Evdovascular treatment is helpful in evaluating the relationship between skull base tumors and surrounding blood vessels before endoscopic transnasal resection of skull base tumors. It can effectively block the donor artery, reduce the probability of intraoperative bleeding, effectively treat the rupture of large blood vessels, and reduce the occurrence of serious complications. The efficacy and safety are both high.

With the intensification of polar scientific research, the demand for energy is increasing rapidly, and the environmental pollution and carbon emissions caused by polar energy consumption dominated by fuel cannot be underestimated. It is urgent to build a microgrid system based on clean and renewable energy to ensure the green and sustainable development of polar scientific research. Based on the analysis of the resource characteristics of the Antarctic research station, the wind-solar microgrid structure is selected and the system capacity optimization configuration model is established in this paper. The polar environment is complex and diverse, which has a significant impact on the energy storage system. In order to ensure the future operation of the microgrid with better adaptability, the influence of energy storage capacity attenuation on the economic benefits of the microgrid system is considered in detail in the configuration stage, and the influence of temperature, charge-discharge rate and cycle times on the battery capacity is analyzed. A multi-factor coupling battery capacity attenuation model based on adaptive grey relational analysis is established, and it is incorporated into the optimal configuration model. An example of Antarctic scientific research station is solved and analyzed by using improved particle swarm optimization. The simulation results show that the microgrid configuration scheme considering energy storage capacity attenuation can reduce the probability of battery overcharge and overdischarge, extend the service life of the battery, and is more suitable for polar regions.

Contamination of spoilage and pathogenic microorganisms in food substrates can negatively influence food quality and threaten food safety. The application of physicochemical antimicrobial strategies can effectively inhibit the growth and reproduction of harmful microorganisms, but may also cause irreversible negative effects on food quality. Some antagonistic yeasts alone or combined with antimicrobial agents can effectively control harmful microorganisms. This review systematically and comprehensively summarizes the existing literature on the antimicrobial effects and mechanisms of yeasts and their derivatives from the above two aspects. The sources, species and mechanism of action of antagonistic yeasts as well as their antimicrobial effects when combined with other antimicrobial technologies are discussed. Additionally, the advantages and limitations of yeast as a natural drug carrier combined with various chemical antimicrobial agents are analyzed. This review aims to provide a scientific reference for developing new yeast-based antimicrobial agents, which will be helpful in improving food quality and ensuring food microbial safety.

This paper constructs the innovative development model of cultural and tourism integration based on the digital development process of cultural and creative industries and the rural tourism industry under the background of informationization. Then, it analyzes the comprehensive development level, coupled and coordinated development characteristics, and regional differences of cultural and creative industries and rural tourism industries in the whole country and 7 regions by using the coupled and coordinated degree model. Finally, the effectiveness of the digital development model of cultural and tourism integration is analyzed through the multiple linear regression model, and the moderating effect of the digital development model of cultural and tourism integration on the regional service capacity, infrastructure, and economic development is explored in depth. The results show that for every 1 percentage point increase in the level of digitalized development of cultural and tourism integration, the employment in the regional tertiary industry increases by 1.5%, the level of infrastructure development increases by 1.6%, and the level of local economic development grows by 1.2%. This study enriches and improves the content framework of the research on the high-quality development of rural tourism and provides new analytical ideas for the research on the high-quality development of rural tourism and cultural and creative industries.

With the rapid development of Internet communication technology, the tourism industry will certainly transform and upgrade to the direction of wisdom, and the organization and dissemination of tourist destination information will become a breakthrough in tourism development. This paper firstly constructs a tourism management system (DMS) in line with the idea of smart tourism development by constructing a process line from market opportunity analysis, interest motivation analysis, strategic planning stage, strategy implementation stage and evaluation improvement stage, respectively. Secondly, the evaluation model of tourism destination development based on logistic regression is systematically constructed, and the parameter estimation method is used to estimate the value for 8 influencing factors that affect the development of tourism destinations. The results show that through the empirical analysis of the Guizhou smart tourism destination management system, it is found that the AUC value shows an increasing trend, and the 5km grid has the smallest AUC value. When the grid continues to increase, the AUC value shows a decreasing trend, slowly decreasing from 0.836 (20km) to 0.844 (25km). It shows that the intelligent tourism destination management system constructed in this paper is reasonable and lays the theoretical foundation for realizing regional barrier-free tourism and achieving the development goal of integrated symbiosis.

Foodborne pathogenic bacterial biofilm is a spatially structured multi-cellular community that is adhered to food contact surfaces. Conventional disinfection methods cannot effectively prevent and control bacterial biofilm due to its strong adhesiveness and stress resistance, causing food safety hazards and a serious effect on consumer health. In this article, recent studies on the formation mechanism and control strategies of foodborne pathogenic bacterial biofilm are reviewed. The roles of the functions of bacterial long-chain appendages, quorum sensing system and extracellular polymeric substances (EPSs) in the formation of bacterial biofilm are summarized and discussed based on improved biofilm adhesiveness, changed bacterial state, and enhanced stress resistance. This review divides the existing strategies for biofilm prevention and control into three categories: physical, chemical, and biological, and analyzes the principle, advantages and disadvantages of each category in order to provide a theoretical reference for the development of more efficient strategies for biofilm prevention and control in the food field to achieve better prevention and control of food microbial safety.

The form and overall style of rural settlements are the carrier of the rural regional context and aesthetics. At present, China’s rural areas are facing a disorderly style and urbanisation. This study is based on similarity aesthetic regularity and visual aesthetic regularity; on the one hand, this work researches the method of building interface coordination from the aspects of form, material and colour, and puts forward the interface construction method of strong contrast, medium contrast and weak contrast according to the rural areas. On the other hand, this study analyses people’s perception characteristics of the style from the visual psychological level, explains the skills for the rural interface and sequence arrangement based on the relationship between visual matching and the bottom of the picture and constructs the aesthetic image under the new overall relationship of the place. Finally, this study puts forward a series of strategies for rural style construction, such as symbol concatenation, contrast reconstruction and aesthetic conflict transformation, to constructing a new aesthetic image of place so as to provide ideas and methods for the development of the rural style in the future.

Hyperspectral imaging technology can obtain the spatial and spectral three-dimensional imaging of substances simultaneously, and obtain the unique continuous characteristic spectrum of substances in a wide spectrum range at a certain spatial resolution, which has outstanding advantages in the fine classification and identification of biological substances. With the development of hyperspectral imaging technology, a large amount of data has been accumulated in the exploration of data acquisition, image processing and material inspection. As a new technology means, hyperspectral imaging technology has its unique advantages and wide application prospects. It can be combined with the common biological physical evidence of blood （stains）, saliva, semen, sweat, hair, nails, bones, etc., to achieve rapid separation, inspection and identification of substances. This paper introduces the basic theory of hyperspectral imaging technology and its application in common biological evidence examination research and analyzes the feasibility and development of biological evidence testing and identification, in order to provide a theoretical basis for the development of new technology and promote hyperspectral imaging technology in related biological examination, to better serve the forensic practice.

Abstract. We measured πE invariant mass spectra below and above the K¯N mass threshold in the K−d → NπE reaction in order to study the K¯N interaction and the Λ(1405) resonance. This reaction can be described by the two-step process: (i) K¯N1 → K¯N followed by (ii) K¯N2 → πΣ, where N1 and N2 are nucleons bound in the deuteron. We deduced the S -wave scattering amplitude of K¯N →K¯N in the framework of the K¯N πΣ coupled channel so as to reproduce the observed πΣ spectra in the I = 0 channel. We found a resonance pole at 1417.7-7.4+6.0 (fitting error)-1.0+1.1 (systematic error) - i[26.9-7.9+6.0 (fitting error)-2.0+1.7 (systematic error)]MeV/c2.

Under detonation loading, the prefabricated fragments in the warhead will be greatly deformed and even broken. In order to explore the model of deformation, the dynamic response of double-layer spherical tungsten fragments under detonation loading was studied. Firstly, a typical cylindrical warhead model was numerically simulated. The simulation model for the characteristic section only includes the quarter model for the double row fragments in the axial direction, in order to obtain the deformation response of the fragments under the detonation loading. The full-size 1/4 simulation model is designed to obtain the axial velocity distribution of the fragment. In the characteristic section, the charge diameter was used as the variable to simulate five charge sizes, and the fragment deformation law was obtained. In order to verify the correctness of the simulation, the warhead of 400 mm caliber was tested, and the flight speed of the fragment was measured. Some deformed fragments were obtained by soft recovery and their cross-section microstructure were analyzed by scanning electron microscope (SEM). The results show that the deformation of the inner layer of the double-layer spherical tungsten alloy fragment is more serious under the action of the internal explosion load, because it is squeezed by the internal explosion load and the outer layer fragment at the same time. The final dispersion velocities of the inner and outer fragments tend to be the same, and there is no significant difference in the distribution of fragments.

Soft magnetic materials have been widely applied in modern industries as energy materials. In recent years, with the increasingly high frequency and miniaturization of magnetic components, as well as the call of energy conservation and environmental protection, the development and research of high-performance soft magnetic material are of great important significance. The present work generalized the development history of soft magnetic alloys comprehensively, from the viewpoints of chemical compositions, microstructures, magnetic properties, application fields, and advantages and disadvantages of different soft magnetic alloys. The involved alloy systems include primarily traditional crystalline alloys, amorphous/nanocrystalline alloys, and high entropy alloys. It is found that the microstructure induced by alloy compositions plays a dominant role in soft magnetic property, especially the coercivity. Then the influence factors on the coercivity of alloys and the related micro-mechanisms were discussed, in which the grain size in traditional alloys or particle size in nano-crystalline alloys is crucial to achieve lower coercivity. Therefore, the development of the micro-mechanisms of coercivity in high entropy soft magnetic alloys was described. Finally, it was expected that high entropy soft magnetic alloys would be more beneficial to modulate alloy properties due to the diversification of microstructures induced by the mixing of multi-principal elements, which shows great potential to serve as a new generation of high temperature soft magnet materials.

The load of ball cage type constant velocity joint of military off-road vehicle is larger than that of traditional vehicle, and the working condition is bad, which may cause contact wear, as well as the fracture of the cage under the angle between large axes. Therefore, it is very important to study the contact stress and the strength of the cage under the bad working condition. In this paper, a typical military off-road vehicle ball cage constant velocity joint is taken as the object. Firstly, the contact stress between the steel ball and the inside and outside raceway is theoretically analyzed and simulated. The simulation and analytical results are compared to verify the correctness of the simulation model. Secondly, according to the load transfer relationship between the key parts of the universal joint and the physical experiment, the reason and process of cage fracture are analyzed. Finally, the static torsion test under the ultimate axial angle is carried out, and the hardness test is carried out on the section of the cage. The strength distribution along the thickness is obtained through the relationship between hardness and strength conversion. The results show that the strength of the cage meets the requirements under normal working conditions, but may be broken under bad working conditions. This research can provide theoretical reference for the design and manufacture of constant velocity joint for off-road vehicle.

Stiffened plates is a common structural form in aviation structure. Different types of stiffened plates and different manufacturing processes will affect its mechanical behavior and failure mode. The finite element method is used to establish numerical models of titanium alloy stiffened plates, and to study the effects of the T, L and Z type stiffened plates on buckling mode and failure. The influence of manufacturing processes such as welded, spot welded, riveted and integral panels on buckling and post buckling properties are analyzed. It is shown that the buckling load and the failure load of the T-type stiffened plate are the maximum one. Different manufacturing processes have great influence on the failure load and post-buckling load capacity, among which the post-buckling load capacity of welded stiffened plate is the largest one. At the same time, the most effective stiffening method of 600 mm×600 mm stiffened plate structure is given.

In order to study the surface movement and deformation law caused by the middle deep buried thick coal seam mining in northern Shaanxi Province, the first working face （112201 ｗｏｒｋｉｎｇ ｆａｃｅ） of Xiaobaodang Coal Mine which lies in the middle of the third phase planning area of Yushen Mining Area was taken as the research area. The surface movement and deformation characteristics, the movement deformation parameters and development laws of surface cracks caused by coal mining are obtained through the combination of observation station, GNSS observation station and theoretical analysis. The results show that: the maximum subsidence and the maximum subsidence coefficient were 3 840 mm and 0.66 respectively caused by mining of 112201 coal face. The duration of surface movement and deformation was about one and a half years. The start-up stage last 18 days, and the active stage last 110 days. Among the active stage, the surface movement and deformation are mainly concentrated in 43 days. The surface subsidence in the active stage was 91.4% of total subsidence value. The degree of development of surface crack induced by mining of 112201 coal face was weak. Relatively speaking, the development degree of surface cracks above the cut hole was greater than that above the trough, and the degree of the surface cracks above the goaf was weakest. The surface crack in the 112201 coal face was developed behind the mining position, and the width showed a “single peak” dynamic characteristic. There is coupling synchronization between the dynamic change characteristic and the velocity of surface subsidence.

In clinical practice, cerebral small vessel disease (CSVD) and sleep disorders are two common diseases in the elderly, the correlation between the two is not clear yet. Studies have found that different types of sleep disorders have different mechanisms for the occurrence and development of CSVD. Sleep⁃disordered breathing is a vital risk factor for CSVD. However, non⁃breathing⁃related sleep disorders may not only increase the risk of CSVD, but also be an important clinical manifestation of the disease. Based on whether sleep disorders are related to breathing or not, this article reviews the correlation between CSVD and sleep⁃disordered breathing, CSVD and non⁃breathing⁃related sleep disorders, respectively, to improve the understanding of the correlation between the two diseases, and to promote the comprehensive management and intervention research of CSVD.

The thermo-mechanical fatigue（ TMF） behavior of casting alloy Ti-48 Al-2 Cr-2 Nb was researched. The tests were performed thermo-mechanically in-phase（ IP） at 400℃ ～ 800℃ . During TMF,tests strain was controlled. The result of this IP TMF was compared with 400℃ and 800℃ isothermal low cycle fatigue（ LCF）. The result shows that the fatigue life of Ti-48 Al-2 Cr-2 Nb alloy in 400℃ ～ 800℃ TMF condition is longer than 400℃ and 800℃ LCF within high strain region. Within low strain region,it is slightly shorter than 400℃ LCF and within the dispersion zone of 800℃ LCF. In this TMF condition,no evidence shows hardening or softening phenomenon. SEM analysis shows that inter-lamellar and inner-lamellar cracking and trans-lamellar tearing can be observed on the fracture surface.

This paper mainly studies the therapeutic effect of azithromycin and hydroxychloroquine on COVID-19. Severe acute respiratory syndrome is one of the key clinical manifestations of COVID-19, and azithromycin is considered to be a feasible treatment. The purpose of this study is to investigate how to use azithromycin to treat COVID-19 better. This article describes the therapeutic effect of azithromycin alone on COVID-19, and the effect of azithromycin and hydroxychloroquine when used in combination with COVID-19. Several studies have shown that although azithromycin has antiviral activity, azithromycin alone has no significant effect on the treatment of COVID-19. In contrast, multiple data show that the combination of azithromycin and hydroxychloroquine has some efficacy in the treatment of COVID-19, and the efficacy is related to the number of days the patient has been ill. The discovery impacts the treatment by providing a different perspective on the world’s treatment of COVID-19.

Global warming and rapid urbanization are changing the livability of cities. The eco-livability (EL) in Jiading, a newly emerging urban sub-center in the northwestern part of Shanghai megacity, is assessed from a climatic perspective, by composing an EL index consisting of meteorological hazards, human comfort, vegetation ecology, and air quality, based on multi-source observations. The results show that the EL in Jiading has improved with the restoration of green spaces and the reduction of air pollution. However, with the rising risk of weather extremes (e.g., heat waves, rainstorms) brought by the warming world, the EL in Jiading is being undermined. We should take preventive measures to improve our ability to resist climate risks.

Diao Jiaolou is a typical component of minority housing culture. Strengthening the study of the hanging foot building is to inherit the culture of traditional residential architecture. By classifying and analyzing the architectural characteristics of minority housing, the characteristic elements of housing are refined for this architecture and industrialized using modern means and methods. Based on protecting the ethnic heritage, modern technology uses to leave traces of the times and organize the new rural construction in western Hunan. With the acceleration of urbanization, it is necessary to establish a mechanism for renovating traditional minority dwellings with regional characteristics and apply it to the refurbishment and development of settlement dwellings.

In view of problems of strong interaction effect between STATCOM and power grid under weak power, the power voltage feed-forward control strategy is not effective in resisting power grid voltage distortion due to the delay, a current tracking control strategy for mine chain STATCOM considering control delay was proposed. The control strategy is based on the traditional proportional resonance control strategy, and compensation link is added in power grid voltage feed-forward link. The compensation link is equal to reciprocal of product of sample delay and control delay transfer function. The approximation expression of compensation link available to meet the requirements is derived through McLaughlin expansion. The compensation strategy added compensation link can eliminate control delay and avoid influence of grid voltage distortion, so that the STATCOM can still work normally when power grid voltage harmonics are large. The simulation results show that the control strategy has strong ability to resist power grid voltage disturbance and good control effect of current tracking.

BackgroundSubchorionic hematoma (SCH) is common in early pregnancy achieved by in vitro fertilization-embryo transfer/frozen embryo transfer (IVF-ET/FET), and is associated with adverse obstetric outcomes. However, there are no methods known to accurately predict the occurrence of SCH.ObjectiveTo establish a nomogram prediction model for predicting the risk of SCH in early pregnancy with IVF-ET/FET and to analyze pregnancy outcomes of patients with SCH.MethodsPatients who underwent IVF-ET/FET treatment and were diagnosed with clinical pregnancy were enrolled in our study. A total of 256 patients with SCH were enrolled in the SCH group, and 526 patients without SCH in the control group. Logistic regression was used to screen risk factors for SCH, and the nomogram was developed according to the regression coefficient of relevant variables. Discrimination, effect, calibration, and the predictive model’s clinical usefulness were assessed using the C-index, the area under the receiver operating characteristic standard curve, calibration plot, and decision curve analysis. Internal validation was assessed using bootstrapping validation. The effects of SCH on pregnancy outcomes were analyzed.ResultsA multivariate logistic regression analysis showed that fresh embryo transfer, polycystic ovary syndrome, hydrosalpinx, and thin endometrium were risk factors affecting the occurrence of SCH. Based on the above factors, a predictive model for the risk of SCH was created. The model displayed good discrimination, with a C-index of 0.783 (95% confidence interval: 0.750–0.816), area under the receiver operating characteristic standard curve of 0.783, and good calibration. A high C-index value of 0.765 could still be reached in the interval validation. Decision curve analysis showed that the nomogram was clinically useful when the intervention was decided at the SCH possibility threshold of 4%–87%. For patients with successful deliveries, the occurrence of SCH did not influence the gestational weeks of delivery, mode of delivery, preterm birth, height, and weight of the newborn.ConclusionWe screened the risk factors for SCH in patients who underwent IVF-ET/FET treatment. Successful establishment of a nomogram can effectively predict the occurrence of SCH. Furthermore, the incidence of miscarriage is higher in patients with SCH.

The characterisation of the cooking oils presents a significant challenge due to minor changes in their dielectric behaviour. In this paper, a new metamaterial-based sensor incorporating a split-ring resonator (SRR) with a microstrip transmission line is presented to characterise cooking oils. The design demonstrates metamaterial characteristics of negative permittivity and permeability simultaneously at the resonance frequency. Furthermore, its operation in the range of millimetre-wave frequencies can further enhance its sensitivity, especially for liquid materials. The sensor’s novelty is the operation at millimetre-wave frequencies that offers a high shift in the transmission coefficient while operating at 30 GHz. The sensor’s performance analysis is undertaken by using six MUTs with dielectric constants ranging from 0.126 to 4.47. The presented structure designed on 12 × 8 mm2 Rogers substrate offers a sensitivity of 1.12 GHz per unit change in dielectric constant. The phase's shift demonstrates a lower percentage error than the amplitude and linearly moves towards higher frequencies with the increase in dielectric constant and tangent loss of MUT. The designed sensor can be prominently useful for detecting liquids' chemical characteristics in chemistry and medicine fields.

Recent heavy-ion collision experiments reported a surprisingly short lifetime for the hypertriton, which has been recognized as the hypertriton lifetime puzzle. Our J-PARC E73 experiment contributes to solve this puzzle with an independent experimental method by employing 3He(K−, π0) 3ΛH reaction. In this contribution, we will demonstrate our capability to provide 3ΛH binding energy information by deriving the production cross section ratio, σ3ΛH/σ4ΛH. The production cross section data for 3ΛH and 4ΛH are already available as the pilot run of E73 experiment and data analysis is in progress.