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(NH)SO, CaCl, NaSiO and NaNO were selected as surrogates of inorganic seed aerosols of ambient atmosphere of Chinese urban areas, respectively, to study their effects on the formation of secondary organic aerosol (SOA) in the toluene/CHONO/NO photooxidation system. The SMPS and aerosol laser time-of-flight mass spectrometer (ALTOFMS) was used to measure the aerodynamic size and chemical composition of individual SOA particles in real-time. Experimental results indicate that either the growth or products of SOA is affected by the presence of inorganic seed aerosol. Inorganic seed aerosols would promote growth rates of SOA formation at the start of the reaction and inhibits its formation rate with prolonging the reaction time. In the case of about 100 μg m seed aerosol load, the addition of NaSiO induced a same growth rate of SOA formation as NaNO. The influence of four individual seed aerosols on the generation of SOA decreased in the order of CaCl > (NH)SO > NaNO, NaSiO. The presence of NaSiO or NaNO has no obvious effect on the growth rates of SOA formation, but it does increase the yield of organic acid and nitrogen-containing organic compounds, respectively. Besides the significantly effect on the growth rate of SOA formation, the presence of CaCl or (NH)SO can lead to the formation of high-molecular weight species which is found to be positively correlated with the hygroscopic behavior of seed aerosols. The CaCl shows the strongest hygroscopic behavior among the four individual seed aerosols, and the most significant promotion effect on the formation of the high-molecular weight species. It is proposed that the SOA generation enhancement and high-molecular weight products are achieved by particle-phase heterogeneous reactions induced and catalyzed by the acidity of CaCl and (NH)SO seed aerosols. [ABSTRACT FROM AUTHOR]

Marine Isotope Stage 3 (MIS 3, at 60–25 ka B.P.) was a short interstadial within the Last Glacial period. A generally warm and wet climatic condition during the MIS 3 period has been suggested by many previous studies. Quantitative climatic reconstruction and studies of seasonality, however, have been seldom attempted given the scarcity of useful proxy indicators. A full understanding the climatic characteristics during this period is hampered by their absence. This is especially the case in the East Asian monsoon region in North China, which is very sensitive to climatic change. To help fill this knowledge gap, we have determined the stable carbon (δ 13C) and oxygen isotope (δ 18O) compositions of tooth enamel from fossil mammals (Bubalus sp [buffalo] and Cervus elaphus [red deer], dated at ∼33–31 ka B.P.) recovered from Longquan Cave in North China. We use these data to constrain ecology, local air temperature and precipitation amounts during the late MIS 3. The average δ 13C (VPDB) of tooth enamel (−14.4‰ and −8.8‰, respectively for buffalo and red deer) indicate that C 3 plants comprised the main diet of animals living in this area. Pollen assemblages demonstrated that vegetation mainly consisted of grasses and herbs (∼64%) with trees only accounting for about 26%. These results indicate a landscape of open steppe with sparsely distributed trees. The reconstructed climate derived from tooth enamel δ 18O was relatively colder and drier than present-day condition, with mean annual air temperature ranging from 4 to 13 °C and mean annual precipitation ranging from 360 to 670 mm. Moreover, the inferred summer and winter half-year temperatures were respectively 8–24 °C and −2 to 5 °C, which represents either similar or weaker seasonality than at the present time. The inferred cold and dry climate suggested by our study contrasts with the warm and wet conditions previously reconstructed using proxy indicators from bulk soil samples in North China. In comparison to the long-term, time-averaged climatic condition reflected by those soil proxies, the stable isotope compositions of fossil more likely recorded climatic conditions at annual or seasonal time-scale. The inferred annual cold/dry climate at Luanchuan Cave suggested by our data may indicate a short climatic cooling event from Greenland Interstadial (GIS) 5 to its following stadial. Mean annual temperature fluctuated by ∼8 °C during this interstadial-stadial cycle. • Tooth δ 13C and pollen data suggest an open steppe at Luanchuan during late MIS3. • A MAT of 4–13 °C and a MAP of 360–670 mm were inferred from tooth δ 18O and δ 13C. • Seasonality was either similar or weaker at Luanchuan during late MIS3 than today. • The inferred annually cold/dry climate may indicate an abrupt cooling event. • Mean annual temperature fluctuated by ∼8 °C during the interstadial-stadial cycle. [ABSTRACT FROM AUTHOR]

Objective: To determine willingness to pay for a diabetic retinopathy screening, and its determinants, among people with diabetes mellitus in Qujiang District of Shaoguan City, rural Guangdong, southern China., Design: This cross-sectional study was conducted through a large-scale screening programme in 2019. We randomly selected 575 (21.5%) among 2677 people over 18 years old with known diabetes who attended the screening. Participants elected to pay nothing or RMB10-RMB120 (US$1.6-US$18.8), in RMB10 intervals, displayed on printed cards. One trained interviewer collected all the data., Setting: Ten primary health centres in Qujiang District of Shaoguan City, Guangdong., Participants: 545 from the 575 randomly selected people (94.8%) agreed to participate in the study., Outcome Measures: Proportion of participants willing to pay anything for screening, mean amount they were willing to pay and determinants of these figures., Results: Among 545 participants (mean age 64.6 years (SD±10.4), 40.7% men), 327 (60.0%) were willing to pay something for screening, of whom 273 (83.5%) would pay RMB10-RMB30 (US$1.6-US$4.7). People living in rural areas and those from lower-income families were more likely to be willing to pay anything, while men, urban residents and those covered by employer-linked insurance were willing to pay larger sums (p<0.05 for all)., Conclusion: Nearly two-thirds of participants were willing to pay for screening in this screening programme organised at the primary care level in rural China. This finding offers the potential that such activities can be sustained and scaled up through user fees., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Airborne bacterial contamination poses a risk for surgical site infection, and routine surveillance of airborne bacteria is important. Traditional methods for detecting airborne bacteria are time consuming and strenuous. Measurement of biologic particle concentrations using a fluorescent particle counter is a novel method for evaluating air quality. The current study was to determine whether the number of biologic particles detected by the fluorescent particle counter can be used to indicate airborne bacterial counts in operating rooms., Methods: The study was performed in an operating theater at a university hospital in Hefei, China. The number of airborne biologic particles every minute was quantified using a fluorescent particle counter. Microbiologic air sampling was performed every 30 minutes using an Andersen air sampler (Pusong Electronic Instruments, Changzhou, China). Correlations between the 2 different methods were analyzed by Pearson correlation coefficients., Results: A significant correlation was observed between biologic particle and bacterial counts (Pearson correlation coefficient = 0.76), and the counting results from 2 methods both increased substantially between operations, corresponding with human movements in the operating room., Conclusion: Fluorescent particle counters show potential as important tools for monitoring bacterial contamination in operating theatres., (Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.)