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Purposes Bird impact resistance has always been one of the important testing factors for aircraft airworthiness. In order to explore the bird impact resistance performance of civil aircraft nose side panel, three methods of rivet failure ratio assessment, energy method, and residual bearing capacity assessment are used to evaluate. Methods The effectiveness of the numerical model was verified by simulating the bird impact behavior of three types of side wall panels by using PAM-CRASH software, and the reliability of the above method was evaluated according to the bird impact failure of the three test specimens. Findings The research results indicate that the lower the proportion of rivet failures, the better the bird impact resistance of the structure; When the proportion of rivet energy absorption increases and the proportion of skin energy absorption decreases, the anti-bird-collision performance of the structure is improved; Among the above methods, the residual bearing capacity evaluation method can realize quantitative analysis of the bird impact resistance performance. The lower the damage factor value, the better the bird impact resistance performance of the side wall panel. Conclusions By summarizing the applicability and limitations of the bird impact performance evaluation method for side wall panels, this work provides valuable reference for the safety design and research and development of later civil aircraft.

ObjectiveTo understand the mortality trends among residents of Fuling District， Chongqing， before and after the COVID-19 outbreak， and to provide references for the government to formulate disease prevention and control policies and measures.MethodsData on mortality and population in Fuling District from 2017 to 2022 were collected to analyze population mortality and standardized mortality rates， and to compare the changes in the causes of death by year and before and after the pandemic.ResultsFrom 2017 to 2022， the crude mortality rate in Fuling District showed an upward trend （APC=3.04%， P

A new type of Ni-free cryogenic steel has been developed by replacing the more expensive Ni with low-cost Mn， which has become a new hot spot in the current research of steel for liquefied natural gas （LNG） storage tanks. The concept and characteristics of cryogenic steel are introduced in the beginning and then the research of high manganese austenitic cryogenic steel at home and abroad are introduced in this paper. In addition， the requirements on composition and properties of high manganese austenitic cryogenic steel in national and group standards are listed in detail. By comprehensive analysing the effects of different elements on the mechanical properties of high manganese austenitic cryogenic steel， it is concluded that Fe-24Mn-0.45C-3Cr-0.5Cu series high manganese austenitic cryogenic steel has excellent comprehensive properties， and can be used as a reference for the optimization of composition of high manganese austenitic cryogenic steel design. For the welding process， heat treatment can effectively improve the low temperature toughness of high manganese steel. And the research shows that considering the low temperature toughness， shielded metal are welding has better effect than that of submerged arc welding， although there is no big difference between yield strength and tensile strength

Head and neck squamous cell carcinoma (HNSCC) is a solid tumor with high morbidity. In recent years, traditional treatment methods, such as surgery, chemotherapy, and radiotherapy, are going through a bottleneck period, and therefore, new treatment methods are urgently needed to improve the prognosis of patients. Immunotherapy is an emerging treatment method for tumor in recent years, and immune checkpoint inhibitors (ICIs) have been widely used in the clinical treatment of HNSCC and other tumors with a marked clinical effect. This article summarizes the research advances in ICIs in the treatment of HNSCC and the effect of ICIs combined with radiotherapy and/or chemotherapy and elaborates on the adverse reactions of ICI the-rapy, in order to find the best paradigm of immunotherapy for HNSCC patients.

Coxsackievirus A10 (CV-A10) is one of the most common pathogens causing hand, foot and mouth disease (HFMD). The 39 candidate epitope peptides covering the amino acid sequence of the VP1 region of CV-A10 were screened by using the overlapping peptide method and verified by indirect enzyme linked immunosorbent assay (ELISA) and microneutralization inhibition assays. It has been found that candidate epitope P6 (amino acid 39~53 in VP1 region of CV-A10) showed high reactivity with CV-A10 virus serum, and still showed neutralizing inhibition effect at 3.91 μg/mL dilution mass concentration, which was a potential neutralizing epitope. P6 antiserum was prepared by immunizing mice with P6 peptide, and microneutralization test was used to verify its protective effect. The results showed a 1:8.97 geometric mean neutralizing titer for P6 antiserum, which identified P6 as the neutralizing epitope of CV-A10. In order to understand the conservativeness of P6 sequence in CV-A10, the amino acid sequence of the P6 was compared with the representative strains of CV-A10 genotype, and the results showed that P6 was highly conserved in CV-A10. It indicated that P6 is a conserved linear neutralization epitope of CV-A10, which has the potential to resist the infection of various genotypes of CV-A10, and can be used as a target for the development of CV-A10 epitope vaccine. This study aimed to screen and identify linearly neutralizing epitopes on the CV-A10 VP1 protein and to lay a foundation for the development of CV-A10 epitope vaccine and HFMD prevention. [ABSTRACT FROM AUTHOR]

The mass concentration of molybdenum in ammonium molybdate wastewater is usually 0.5~2.0 g/L, which has a high recovery value, but the impurity of iron and aluminum in wastewater seriously affect the recovery rate of molybdenum. The separation and extraction of Mo, Fe and Al from ammonium molybdate wastewater by "impurity removal + ion exchange adsorption" process was studied. By analyzing the existence forms of molybdenum, iron and aluminum at different pH, the precipitation removed the iron and aluminum impurities, and then adsorbed molybdenum in wastewater with ZJ-32 macroporous weak basic anion exchange resin, and the molybdenum resin was desorbed by 12% ammonia water to obtain ammonium molybdate solution. The results show that molybdenum can be separated from Fe and Al under suitable conditions. The filtrate after impurity removal is adsorbed by ion exchange resin, the average recovery rate of molybdenum is 96.47%, and the average desorption rate of molybdenum-bearing resin can reach 99.46% after desorption by ammonia water. The process can effectively avoid the influence of iron and aluminum colloid on molybdenum adsorption, and realize the double resource utilization of molybdenum and iron and aluminum. [ABSTRACT FROM AUTHOR]

Rule mining for knowledge graph is to extract the implied rule knowledge from the knowledge graph, the rules which have the advantages of high accuracy and strong interpretability can be used to knowledge graph completion, denoising, data interpretion and other issues. The latest research progress of rule mining methods in the field of knowledge graph are reviewed, the rule mining methods based on path traversal, frequent itemset and representation learning are introduced in detail. The characteristics, performance and existing problems of various methods are analyzed. The quality evaluation function of rules are discussed. Finally, the future research direction and prospect of this field are discussed and prospected. [ABSTRACT FROM AUTHOR]

It is researched on the carbon dioxide emission and carbon reduction pathway of dry-mixed mortars, by researching the actual production data of a dry mixed mortar factory and its preliminary research and implementation results in carbon emission reduction, combining with relevant literature as well as statistics of Chinese dry-mixed industry. The carbon dioxide emissions of ordinary cementious dry-mixed mortars, special cementious dry-mixed mortars, water-resistant putty and plastering gypsum is respectively 141,297,274,and 126kgCO2/t by life-circle assessments, and the main factors is respectively cement (65%),cement (74%), calcium hydroxide (71%), building plaster and its transportation (49%). The carbon dioxide emissions of dry-mixed mortars production and its transportation is small; as for ordinary and special dry-mixed mortars it is respectively about 12.5 and 20 kgCO2/t. The carbon dioxide emissions of Chinese dry-mixed mortars industry in 2020 is about 2.9 million tons. Annual carbon dioxide emission reduction of this dry-mixed mortars factory is about 100 000 tons in 2020 by adopting a variety of carbon reduction pathway. The carbon dioxide emissions of dry-mixed mortars could be significantly reduced by using solid wastes and thin layer construction. [ABSTRACT FROM AUTHOR]

Ion-bonded graphite intercalation compounds (GICs) is a type of layered materials with excellent performance, such as high electronic conductivity, good thermal stability and large interlayer space, attributed to which it has been widely used in energy storage, catalysis, adsorption, superconductivity and other fields in past years. Ion-bonded GICs is divided into electron-donating GICs and electron-accepting GICs. The typical representives of those two types of ion-bonded GICs are alkali meta-GICs and metal chloride-GICs. In recent years, alkali meta-GICs and metal chloride-GICs have continuously made new breakthroughs in the field of advanced rechargeable batteries. This article summarizes the intercalation processes of alkali metal (Li, Na, K) - GICs and the storage mechanism for alkali metal ions (Li+, Na+, K+) of metal chloride-GICs. The former demonstrates the interaction between alkali metal guests (Li, Na, K) and graphite host by comparing intercalation behavior of alkali metal ions (Li+, Na+, K+) intercalating into graphite. The latter discusses the electrochemical performance of metal chloride-GICs in the field of alkali metal ions (Li+, Na+, K+) batteries anode materials and the superiority of electrochemical performance after modification, and points out challenges what it would face as anode materials in energy storage. Finally, the research tendency and application prospects of ion-bonded GICs are prospected. [ABSTRACT FROM AUTHOR]

The pre-stressing loss induced by sliding friction is one of the most difficult construction techniques for suspen-dome structures, and no effective method is available now. Because the rolling friction is much smaller than the sliding friction, a new cable-strut joint, which includes a roller, was presented to reduce the friction between hoop cable and joints. This new joint has been adopted in the suspen-dome structures of Shandong Chiping Gymnasium. In order to verify the work performance of the new joint in reducing the pre-stressing frictional loss and the structural safety, a numerical procedure for the pre-stressing construction was written using APDL Language on ANSYS software. Using the numerical procedure, the cable force, the member stress and nodal displacement during pre-stressing construction was analyzed. Furthermore, an in-situ construction monitoring was also conducted. The analysis results and in-situ construction monitoring data show that the frictional pre-stressing loss of the new cable-strut joint is about 5% , which is 50% of the traditional cable-strut joint. The member axial stress is less than 50 MPa during pre-stressing construction, therefore, the construction scheme is feasible. The in-situ construction monitoring data has verified the feasibility of the numerical procedure. [ABSTRACT FROM AUTHOR]

For long span steel structures exposed to the solar radiation, the temperature fields of the structures show the features of heterogeneity, time variation and complicacy. However, the temperature effect on structures is often underestimated, resulting in weld failure or even the collapse of structures. The solar radiation absorptance of the commonly used coatings are the key factor in studying the temperature effect of the solar radiation on steel structures. On the basis of document research, a method of measuring the solar radiation absorptance by the spectrophotometer is adopted .which is based on the principle of spectrometry. A total number of 51 specimens classified into 17 groups were studied, and the solar radiation absorptance of different coatings were measured in tests. A conclusion that the color of topcoating is the key factor to the solar radiation absorptance is reached. The temperature fields and temperature effects of the Chiping Gymnasium roof structure with six different coatings were studied based on the solar radiation absorptance obtained in tests. The results show that the topcoating color of the steel components has great influence on the temperature fields and temperature effects of structures under solar radiation. [ABSTRACT FROM AUTHOR]

Construction simulation for a shell-shaped single-layer lattice shell located in Yujiapu was conducted based on ANSYS finite element software. According to actual construction process and the element birth and death technology, the stress changing tendency of key components was obtained and lifting process was analyzed in detail. The monitoring scheme was made and conducted to ensure the safety in erection process for the boxed components which were subjected to large axial force, shear force, moment and torsion at the same time. The results derived by monitoring and simulation were compared. The changing course of bearing displacement was calculated by using nonlinear spring element to accurately simulate mechanical property of double bearing. Results show that displacement would occur at each support due to erection sequence and temperature variation, which should be avoided by taking measures. The stress of lifting point is large during integral lifting process and it almost vanishes after unloading. The simulation method was validated by the agreement between results obtained by monitoring and simulation. The stress and displacement of key components are in control and the construction scheme can satisfy the need of construction. [ABSTRACT FROM AUTHOR]

In order to avoid friction loss of loop cable, cable-member systems with radial spherical plain bearing was induced in suspended dome which built prestress on loop cable by the rotation of strut. It differs from the traditional loop-cable prestressing method in which prestress is built through the slip of the loop cable. In this paper, the suspended dome of the Bicycle-Gymnasium for East Asian Games was taken as the research subject. Forward analysis of fonn-finding and back analysis of form-finding were carried out using ANSYS and the lofting state of the structure before tension was obtained. It is proved that back analysis is more suitable for finding lofting state of cable-member systems with radial spherical plain bearing. A mixed tension method is used according to above-mentioned analytical result, which prestresses radial cable firstly and loop cable secondly. By simulating the whole process of prestressing construction, pre-tension force and nodal displacements are obtained. [ABSTRACT FROM AUTHOR]

In this paper, radial spherical plain bearing is introduced into the cable-member systems of suspended-dome as the rigid rotational core of strut up-joint. Axial loading tests were carried out in order to obtain its ultimate bearing capacity and understand behavior of the joint. The tests show that rotation capability of the rigid rotational core remains satisfactory even though ear plate of the joint has already yielded. Elastic-plastic FEA with contact interface element was carried out using ANSYS as a supplement to axial loading tests and the failure mechanism of the joint was analyzed in depth. Both test and FEA show good mechanical properties of the joint. At last, some advices on designing strut up-joint with radial spherical plain bearing and the concept that articulated joint can have a rigid rotational core is proposed. [ABSTRACT FROM AUTHOR]

Objective: To illustrate the role of methylation level of hMLH1 gene promoter in different stages of gastric carcinogenesis by methylation-specific PCR (MSP) detection of samples from paracancerous tissue and gastric cancer tissue., Methods: Methylation status of hMLH1 gene promoter of 40 patients undergoing radical stomach cancer operation in the Tumor Research Institute of China Medical University between January 2006 and August 2006 was detected by MSP. For each patient, 2 samples were chosen from the cancer site, paracancerous tissues of 1 cm, 3 cm, 5 cm away from the cancer site, separately. One sample was used in pathology examination, and the other in methylation detection., Results: Positive rates of hMLH1 gene promoter methylation in the paracancerous tissues of 1 cm, 3 cm, 5 cm away from the cancer site were 10%(4/40), 12.5%(5/40) and 2.5%(1/40) respectively, which were significantly lower than 32.5%(13/40) in cancer site(all P<0.05). Pathological examination showed precancerous lesions in 23 samples of paracancerous 1 cm and 3 cm tissues and normal tissues in 24 samples of paracancerous 5 cm tissues. Positive rates of hMLH1 gene promoter methylation in the cancer site, paracancerous tissue and normal gastric tissue were 32.5%(13/40), 8.7%(2/23) and 0(0/24) (P<0.01). For cancer tissue penetrated the gastric serosa, 8 out of 14 tissue samples were positive methylation (57.1%), which was significantly higher compared with 5 out of 26 tissue samples without penetration of gastric serosa(19.2%). Positive rate of hMLH1 gene promoter methylation in tissue samples with 7 or more of metastatic lymphatic node number was 61.5%(8/13), which was higher compared to that with less than 7(5/27, 18.5%) (P<0.05). No significant differences of positive rate of hMLH1 gene promoter methylation were found between different tumor gross types, tumor grow pattern, tumor differentiation degree, patient age and sex(all P>0.05)., Conclusion: Hypermethylation of hMLH1 gene promoter may be associated with the carcinogenesis stages and progression of human gastric cancer.

Homoacetogens are a group of microorganisms with application potential to produce chemicals and biofuels by the bioconversion of synthesis gas. In this study, we collected waste activated sludge samples to screen homoacetogens by Hungate anaerobic technique, and studied the effect of pH on acetate and alcohol production from H2/CO2 gas. The mixed culture contained Clostridium ljungdahlii, Lysinibacillus fusiformis and Bacillus cereus. Acetate concentration achieved 31.69 mmol/L when the initial pH was 7. The mixed culture containing homoacetogen could converting H2/CO2 to acetate, which provides an efficient microbial resource for the bioconversion of synthesis gas.

Objective: To observe the stability and sensitivity of transcription mediated amplification (TMA) system, and to compare it with real-time reverse transcription polymerase chain reaction (RT-PCR) in amplifying serum HCV RNA in HCV infected patients., Methods: TMA system was established by moloney murine leukemia virus (MMLV) reverse transcriptase, T7 RNA polymerase and 2 specific primers firstly, and then its stability and repeatability were compared at different storage temperatures by the correlation change of HCV RNA amplification curve. The sensitivity difference between TMA and RT-PCR was evaluated by amplifying a group of 10-fold diluted HCV RNA samples which were transcribed in vitro. A total of 101 serums of chronic HCV infected patients were measured by TMA system and RT-PCR to observe the positive rate and their correlation. Linear correlation and linear regression were used to observe the correlation of the two methods., Results: TMA system was successfully established. TMA system was not stable when stored at 20 °C (placed for 24 hours only), but it was stable for 6 days when stored at 4°C or within 6 months when stored at -20 °C . Compared with RT-PCR whose reagent was made by Hunan Sansure Biotechology Corporation, TMA system showed 20 positive samples and 11 negative samples in a total of 31 samples. So was the RT-PCR kit of the Sansure Biotechology Corporation, and the concordance rate of the two methods was 100%. Advanced quantitative study of the 20 positive samples found that the two methods had good correlation and consistency (r=0.91, P<0.01). Compared with the results of RT-PCR whose reagent was made by Shanghai Kehua Bio-engineering Corporation, TMA system had 34 positive samples and 36 negative samples, while the RT-PCR technology had 32 positive samples and 38 negative samples out of 70 samples. The concordance rate of the two methods was 97.1%, with no statistical difference in the positive rate of the two methods (P>0.05). Advanced quantitative study of 29 positive samples found that the two methods had good correlation and consistency (r=0.96, P<0.01)., Conclusion: The stability and repeatability of TMA system are good within 6 months when stored at -20 °C storage temperature. Both TMA and RT-PCR HCV RNA can detect serum HCV RNA well, and the two methods have good correlation and consistency.