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ObjectiveTo evaluate the efficacy of three screening questionnaires for COPD in the community residents of Songjiang District， Shanghai， and to provide a basis for selecting COPD screening questionnaire and process that are more suitable.MethodsCommunity residents aged 40 years or over were randomly selected from the Shanghai Suburban Adult Cohort and Biobank for the study with screening questionnaires and spirometry. Questionnaires included the COPD screening questionnaire （COPD-SQ）， the COPD population screener （COPD-PS） and the revised COPD diagnostic questionnaire （revised-CDQ）. Evaluation of the efficacy of these questionnaires was based on the area under the receiver operating characteristic curve （AUC） of the subjects. DeLong test was used to compare the accuracy of different questionnaires； Z test was used to compare the accuracy of different cut-off values for the same questionnaire.ResultsAmong 3 184 community residents， a total of 259 （8.1%） COPD patients were screened by spirometry. AUC values of these 3 screening questionnaires were >0.7 indicating that they were reliable COPD screening tools. The sensitivity and specificity of the questionnaires at the recommended cut-off values were COPD-SQ （63.7% and 72.2%）， COPD-PS （12.0% and 96.1%）， and revised CDQ （78.8% and 52.7%）， with the COPD-SQ having the highest screening accuracy （AUC=0.754）. The optimal and recommended cut-off values for the three questionnaires differed in this population， but the difference in accuracy was statistically significant only for COPD-PS. The optimal cut-off values for the three questionnaires differed between male and female， and the sensitivity and accuracy of COPD-SQ and COPD-PS improved when lower cut-off values were used for women. The AUC was greater when two questionnaires were utilized simultaneously for screening， but the differences were not statistically significant.ConclusionThe COPD-SQ is recommended for primary COPD screening； a lower cut-off value for women should be considered. The COPD screening questionnaire needs to be further improved for the early diagnosis and treatment of COPD patients.

Ultra-high strength aluminum alloy has achieved extensive application in the nuclear，aerospace，and aviation industries because of its high specific strength and low density. The fifth generation of ultra-high strength aluminum alloy has been produced，and in comparison to the fourth generation’s 600 MPa level，its ultimate strength has been consistently redefined and increased from 650-700 MPa to 750 MPa or even 800 MPa. This paper reviews the history of the research on aluminum alloys with ultra-high strengths and introduces the current state of development both domestically and internationally. The key issues and recent research development are further explored，including computer simulation，thermal deformation，heat treatment，homogenization，melting，and casting，as well as composition design. Finally，combined with the development needs of future equipment and domestic technology status，it is pointed out that in-depth study of basic theory to solve the problem of comprehensive performance matching，the promotion and application of special materials in specific application scenarios are the development trend and important direction of ultra-high strength aluminum alloy.

The room temperature tensile properties and elevated temperature tensile properties of peak aged Al-Cu-Mg-Ag hub forgings after different heat exposure temperatures and heat exposure time were tested，and the thermal stabilities of the forgings at different temperatures were compared and analyzed. The results show that Al-Cu-Mg-Ag forgings exhibit good thermal stability. After exposure at 150 ℃ for 1 to 100 h，there were no significant changes in room temperature tensile properties and elevated temperature tensile properties. Short time heat exposure at 150-200 ℃ for 1 h does not reduce the overall performance，but the strength of Al-Cu-Mg-Ag forgings decreases with the increase of heat exposure temperature and the extension of heat exposure time. After 100 h of exposure at 200 ℃ and 250 ℃，the room temperature yield strength remains 61.1% and 37.2 %，and the room temperature tensile strength remains 77.8% and 60.8%，the elevated temperature yield strength remains 61.6% and 42.8%，and the elevated temperature tensile strength remains 67.5% and 47.6%，respectively. The main precipitates of Al-Cu-Mg-Ag forgings are Ω phase and θ′ phase. Under the experimental conditions of Kt=1 and R=0.1，the room temperature fatigue limit after 200 ℃/10 h heat exposure is 278 MPa，which is 10.6% lower than the fatigue limit of 311 MPa before heat exposure.

ObjectiveAntibiotic resistance genes （ARGs） have received wide attention all over the world. The purpose of this study was to explore the bacterial community structure， the types and levels of antibiotic resistance genes in a water body in east China， and to compare and analyze the characteristics of microbial species distribution and antibiotic resistance gene distribution in various water environments.MethodsA total of 10 households in Haimen City， Jiangsu Province were selected and their surrounding water environment samples were collected. 21 water samples including river water （4）， Mingou water （9） and well water （8） were collected for metagenomics sequencing， assembled with MetaWRAP， annotated with CARD database， and analyzed with R software.ResultsIn various water bodies， the dominant bacteria phyla was Proteobacteria， the dominant bacteria genera were Deuterostomia， Pseudomonas， Flavobacteriales and Streptomycetaceae. The ARGs annotated were mainly composed of quinolones， aminoglycosides， macrolides and beta-lactams antibiotic resistance genes. The top four relative abundance of resistance genes were macB， RanA， evgS and TxR， The average absolute abundance and expression of resistance genes in well water and Mingou water were higher than those in river water.ConclusionMultiple ARGs are detected to varying degrees in well water， river water， and Mingou water bodies， and the expression of resistance genes in well water and Mingou water bodies is higher than that in river water bodies， possibly due to human production and living activities.

The microstructure and performance homogeneity of 80 mm thick ultra-wide 7B50-T7751 plate with different widths and thicknesses were studied by means of mechanical testing machine and scanning electron microscope, and the fatigue properties were compared and discussed with 7050-T7451 plate. The results show that the ultra-wide 7B50-T7751 plate has excellent mechanical properties. In L and LT directions, the tensile yield strength of 1/2 thickness reaches up to 568 MPa and 545 MPa, and the tensile strength reaches up to 612 MPa and 591 MPa, the compressive yield strength reaches up to 575 MPa and 587 MPa, the fracture toughness in L-T direction and T-L direction reaches 30.16 MPa·m1/2 and 26.47 MPa·m1/2, respectively. The ultra-wide thick plate exhibits certain anisotropy at different width positions, the performance homogeneity in LT direction tends to be better than in L direction. Performance at different width positions with 1/4 thickness shows little difference, while the performance at the edge of 1/2 thickness is better than that of the center. No obvious texture exhibits at 1/4 thickness, however, the main textures at the center of 1/2 thickness are S texture and Brass texture, and the main textures at the edge are R texture, S texture and Brass texture. When the stress ratio is 0.06, the T-L anti-fatigue crack growth rate performance of ultra-wide 7B50-T7751 thick plate is better than 7050-T7451 plate with the same thickness. The fatigue limit of LT smooth sample (Kt=1) is about 7.6% inferior than that of 7050-T7451 plate, while the fatigue limit of notch sample (Kt=3) is about 3.7% higher.

The single-stage & two-stage solution and the single aging-tensile property curves at 110-135 ℃ were studied by using the 7A36 aluminum alloy extruded tube of ϕ250 mm×20 mm and ϕ340 mm×30 mm under industrial production conditions. The optimal heat treatment was adopted to compare the tensile properties of two kinds of aluminum alloy extruded tube.The phase transition temperature was measured by DSC, and the microstructure and tensile fracture were observed by OM, SEM and TEM.The results show that the tensile strength, yield strength and elongation of 7A36 alloy extruded tube can reach 696, 655 MPa and 14.0%, respectively, under the optimal heat treatment. Compared with the process of direct chill casting (DC) ingot & extrusion with high extrusion ratio, the size of grain and precipitated phase is smaller, the width of precipitation free zone is narrower under the process of forging ingot & conventional extrusion, which significantly affects the strength.At the same time, the alloy shows high quenching sensitivity. During solution treatment, quenching micro-cracks are easily induced near Fe-rich phase, which significantly affects the elongation of alloy extruded tube.

Gradient nanostructured materials are regarded as a promising class of architectures with tunable mechanical properties, primarily dependent on the optimization of well-controlled fabrication parameters. In this paper, a microvariable-based constitutive model is incorporated into an integrated finite analysis technique. This approach correlates the fabrication parameters of surface mechanical grinding treatment (SMGT) with the corresponding measured mechanical properties of gradient structured (GS) materials, quantifying the relationship between process parameters, microstructure, and mechanical properties. Through theoretical prediction and experimental verification, it is observed that grain refinement, mechanical strength, and surface hardness are enhanced by increasing processing times and reducing path spacing. The yield stress of the fabricated GS material ranges from 126.8 MPa to 162.2 MPa, an increase of above 2.5 times compared to the original material, with a slight decrease in uniform elongation by a factor of 25.8 %, indicative of an excellent strength-ductility trade-off. The underlying mechanism for improved strength-ductility synergy is discussed, focusing on the importance of the tunable spatial distribution of grain size. This work sheds light on the potential application of gradient nanograined structures at an industrial scale and advances the fundamental understanding of strengthening mechanisms in gradient nanostructures.

Due to the lack of real-time monitoring information of traditional epidemiological investigation methods， in recent years， a new method of obtaining relevant epidemiological information through wastewater analysis has become an effective way to maintain the health of the population， which is called wastewater-based epidemiology. Information obtained from the chemical analysis of wastewater can be used to estimate exposure or consumption of chemicals. This work introduces the principle and the investigation method of wastewater-based epidemiology. Compared with traditional epidemiological survey methods， the advantages and disadvantages of wastewater-based epidemiology are analyzed. Development and prospects of wastewater-based epidemiological investigation methods in China are analyzed and some suggestions are discussed.

Objectives To compare the differences in antibiotic use between COPD and non-COPD residents, and to explore the effect of COPD on antibiotic use. Methods Participants aged 40 years old or over from the Songjiang Adult Cohort were included. Information on prescription and baseline survey was collected based on the health information system. A logit-negative binomial Hurdle model was used to explore correlations between COPD and percentage of antibiotic use and average rate of antibiotic prescribing of different types of antibiotic. Multinomial logistic regression was used to assess the association between COPD and antimicrobial combination therapy and routes of administration. Results A total of 34576 individuals were included and 1594 (4.6%) were COPD patients. During the 6 years' follow-up, the percentage of antibiotic use for COPD patients was 98.4%, which was 7.88 (95%CI: 5.24–11.85) times of that for non-COPD patients after adjusting for potential confounders. The prescribing rate was 3220 prescriptions (95%CI: 3063.6–3385.2) per 1000 person-years for COPD patients, which was 1.96 (95%CI: 1.87–2.06) times of that for non-COPD patients. Other beta-lactam antibacterials, Macrolides, lincosamides and streptogramins, and quinolone antibacterials were the most commonly used types of antibiotic. Except for aminoglycoside antibacterials, both percentage of antibiotic use and rate of antibiotic prescription were increased in COPD patients. COPD patients were more likely to be prescribed a maximum of two antibiotics (OR=1.34, 95%CI: 1.20–1.50); and were more likely to use antibiotics intravenously (OR=2.77, 95%CI: 2.47–3.11). Conclusion COPD patients were more likely to have increased antibiotic use in a large-scale population-based adult cohort, suggesting COPD patients are a high-priority group for the management of antibiotic use in communities. [ABSTRACT FROM AUTHOR]