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Objective To understand and evaluate the knowledge, attitude and practice of female human papillomavirus and HPV vaccine in Chinese mainland. Methods We searched the relevant studies about the knowledge, attitude and behavior factors of HPV infection and HPV vaccine published in PubMed, MEDLINE, CNKI and Wanfang databases about Chinese mainland women from January 1, 1995 to January 31, 2021.Two researchers independently screened the literatures, extracted data and the literatures with quality score≥5 points.Chi square test was used to evaluate its heterogeneity.Begg' s test was used to evaluate publication bias. Results A total of 33 literatures were included, with a total number of 46013 people.The results showed that the total awareness rate of HPV in the population was 65.9%, the lowest rates were 16.0%, 41.2% and 14.4% in Northeast, rural areas and middle school students, respectively; while the highest rates of HPV were 77.4%, 56.3% and 71.0% in Central China, cities and towns and college students, respectively.The main source of HPV knowledge was the network/WeChat official account number (38.9%), and the lowest was family/friend (4.5%).The population's awareness rate of HPV vaccine related knowledge was 41.4%, the highest rates were 51.8% and 69.7% in East China and medical staff, respectively, while the lowest were 23.6% and 12.7% in Southwest and middle school students. Conclusion In order to achieve the total elimination of cervical cancer in China by 2030 as soon as possible, people should strengthen their awareness of HPV and HPV vaccine related knowledge.

Polymer matrix composites (PMCs) have become one of the most important structure materials in the new generation of civil turbofan aeroengine due to their advantages of high specific strength, high specific stiffness, good designability, excellent vibration damping performance and feasible integrity fabrication. The PMCs application in aeroengine abroad based on fan blade, fan casing, acoustic liner and bushing was introduced firstly in this paper. The advantages of PMCs in structure optimization, economy and environmental friendliness were also illustrated. Moreover, new progress of PMCs including micro/nano material hybridization, 3D printing process and metamaterials in aeroengine was analyzed in details. Finally, some suggestions about PMCs application based on the relationship of "design-material-process-evaluation" were proposed for further development of civil turbofan aero engine in China.

Rheumatoid arthritis (RA) is an autoimmune disease characterized by erosive arthritis, eventually leading to joint deformity and loss of function. To standardize the operating standards of RA for traditional Chinese medicine (TCM) and better guide clinical practice, the experts group compiled RA clinical practice guidelines for TCM rehabilitation according to the rules of clinical practice guidelines based on the principles of evidence-based medicine combined with expert consensus and argumentation, and clinical evaluation. Aiming to provide more specialized medical guidance for clinical practitioners, such as rheumatology of TCM, rheumatology of integrated traditional Chinese and Western medicine, TCM rehabilitation, and rheumatology, the diagnosis and treatment process of RA, including scope, normative references, terminology and definitions, diagnostic criteria, assessment criteria, treatment, and other aspects, were systematized and standardized in the guidelines. The part of treatment is divided into rehabilitation treatment, TCM treatment, psychological rehabilitation, diet, and surgical treatment. Rehabilitation therapy includes physical factor therapy, exercise therapy, operation therapy, orthopedic apparatus, and intra-articular injection; and the TCM treatment includes the acupuncture and moxibustion, the massage, the TCM practice and the TCM syndrome differentiation. The guidelines has excellent practicality, scientificity and effectiveness, and it will provide a standardized diagnosis and treatment process for RA's TCM rehabilitation treatment, and provide reliable evidence for better clinical decision-making practice.

The spherical SiO2 was used as raw material to prepare the first-level and second-level microstructure surface by layer-by-layer assembly method. The surface morphology, hydrophobic properties were characterized by SEM and contact angle measurement instrument and then the effect of the low surface energy modifications, different size, different level on the hydrophobic properties was studied, and the hydrophobic stability under different conditions were studied. The results show that the film is changed from hydrophilic to hydrophobic after modification; before modification, hydrophobic performance of second-level microstructure with the mixture of 2 μm and 20 nm SiO2 is higher than 2 μm or 20 nm microstructure in the first level and it is the same after modification, whose contact angle and rolling angle of second-level microstructure is 161.3° and 3.2°, respectively. The second-level microstructure surface can still maintain good hydrophobic performance after experiencing 240℃ high temperature and 200 h ultraviolet irradiation.

A novel kind of lattice-distributed ESTM-fabrics (ES-L) and random-distributed ESTM-fabrics (ES-R) were developed by using polyethersulfone (PES) and U3160 according to ex-situ toughening technology. ESTM-fabrics reinforced 3266 moderate temperature curing epoxy resin composites (ESTM-fabric/3266) were prepared through RTM process. Impact resistance and residual strength of ESTM-fabric/3266 were studied and the ex-situ toughening mechanism was analyzed by fluorescence microscope and SEM. The untoughened U3160 fabrics reinforced 3266 moderate temperature curing epoxy resin composites were studied to compare performance of composites as well. The result of low velocity impact testing shows that the toughened ESTM-fabric/3266 composites exhibit the higher delamination damage threshold load, the lower projected delaminated areas, the slower damage development, compared to U3160/3266 composites without toughener PES (ES-U).The major failure mode is intralaminar crack (transverse matrix cracking), debonding between fibre and matrix in fiber-bundle regions as well as local ply breakage along with ply-matrix debonding.The ES-L allows an increase of 37% in CAI compared to ES-U. Microstructural observation of damage zone reveals that ES-R composite has a homogeneous distribution of phase inversion in the interlaminar regions while ES-L composite exhibits a hard phase composing of the 3266 epoxy resin continuous matrix and a soft phase composing of the nodular structure of BMI in the 3266 epoxy resin continuous matrix. The excellent impact resistance and damage tolerance of ES-L composite are due to synergistic effects of hard phase and soft phase, which can release the stress concentration,give the extra strain energy dissipated and subsequently terminate crack via crack blunting mechanism.

The spherical SiO2 was used as raw material to prepare the first-level and second-level microstructure surface by layer-by-layer assembly method. The surface morphology, hydrophobic properties were characterized by SEM and contact angle measurement instrument and then the effect of the low surface energy modifications, different size, different level on the hydrophobic properties was studied, and the hydrophobic stability under different conditions were studied. The results show that the film is changed from hydrophilic to hydrophobic after modification; before modification, hydrophobic performance of second-level microstructure with the mixture of 2 μm and 20 nm SiO2 is higher than 2 μm or 20 nm microstructure in the first level and it is the same after modification, whose contact angle and rolling angle of second-level microstructure is 161.3° and 3.2°, respectively. The second-level microstructure surface can still maintain good hydrophobic performance after experiencing 240℃ high temperature and 200 h ultraviolet irradiation.

The conductive mechanism of graphene/rubber nanocomposites was introduced.Advances in the synthesis and properties of graphene and its derivatives, modifications of graphene, along with its hybrid fillers, as well as fabrication of related rubber conducting nanocomposites were reviewed.Many factors affecting the electrical properties, such as fabrication method, vulcanization, temperature, pressure, frequency and media etc. were also summarized.It was pointed out that the further research should be focused on multi-component graphene/rubber nanocomposites and its double percolation phenomenon.

To meet the practical needs of rapid and non-destructive detection in fruit and vegetable processing, this paper designs a developed portable near-infrared spectrum quality-detection device. In this design, the digital micromirror device of the near-infrared micro-electromechanical system is used as the light splitting element, and the detection information is obtained by a single-point detector, to realize the miniaturization design of the spectrum detection system and significantly reduce the cost. Moreover, the quality inspection model is established based on the PLS method and the principal component analysis method. From the results of the prediction set, the model established by the logarithm of the original absorption spectrum (1/R) and the PLS method is applicable, with a high correlation coefficient (0.9537) and low corrected root mean square error (0.3776). This research can provide reference data for the design of low-cost, practical, and miniaturized near-infrared spectrum detection systems.

Non-linear viscoelastic characteristics of carbon black (CB)-filled fluoroether rubber mixture samples are investigated by large amplitude oscillatory shear (LAOS) tests. Three analysis approaches based on LAOS tests are then used to discuss correlations between rheological behavior and CB-filling amount. Each non-linear viscoelastic parameter of the mixture presents a three-stage characteristic with increasing CB content, which are attributed to the alteration of CB-elastomer network structure, corresponding to the state where gum continuous phase, CB-elastomer mesophase, and excessive CB agglomerates predominate in the mixture compound, respectively. According to the findings in engineering experiments, a CB content of 35-40 phr is recommended, taking into account tensile, hardness, and aging properties. Excessive CB agglomerates are found to reinforce CB-elastomer networks at elevated temperatures. For cold-resistance properties, structural changes in CB-elastomer network are proven to exert little effect on [T.sub.g], but a higher CB content was found to slightly enhance the cold-resistance coefficient, probably due to the decrease in velocity fraction of gum rubber. Highlights * LAOS tests were utilized to study the influences of CB on fluoroelastomer; * Three-stage alteration was observed in the mixture with increasing CB content; * Correlation between CB content and the engineering properties was discussed. KEYWORDS carbon black-elastomer interaction, fluoroether rubber, large amplitude oscillatory shear, non-linear viscoelasticity, 1 | INTRODUCTION Fluoroether rubber is a special type of fluoroelastomer (FKM), in which the polymerization monomers contain a large proportion of perfluoroethers such as perfluoromethyl vinyl ether (PMVE), perfluoropropyl [...]

In recent years, engineering constructions increase rapidly in western and central areas of China, where expansive soil widely distributes. Since expansive soil is sensitive to water content, the characterization of its shear strength should be carefully conducted. For simplicity and ease of use, the Mohr-Coulomb criterion is often adopted to describe the shear strength of expansive soil. In this paper, the physical meaning of the cohesion and frictional strength of expansive soil are explained, and the variations of the strength parameters with water content are investigated. By fitting to the experimental results from direct shear test and triaxial tests, the changing characteristics of cohesion and friction angle with water content are obtained.