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Measurements of surface ozone (O), nitrogen oxides (NO = NO + NO), carbon monoxide (CO), and dew point were made at Qinghai Lake (QHL), China, a basin in the remote Tibetan Plateau area, in October 2010 and October 2011. The O mixing ratio was found to be high with average of 41 ± 9 ppb in October 2010 and 57 ± 10 ppb in October 2011. The observed diurnal pattern of O mixing ratio was characterized by a minimum between 07:00 and 10:00 local standard time (LST) increasing ~20 ppb to a broad peak occurring between 13:00 and 18:00 LST. This diurnal pattern differs substantially from that observed at WMO's GAW Baseline Observatory located above the basin on Mount Waliguan, ~130 km southeast of QHL. The elevated O mixing ratios observed in the afternoon are attributed to in situ photochemical production in the air trapped in the QHL basin by surrounding mountains. The low O mixing ratios observed in the morning are most likely due to surface removal in a shallow nocturnal boundary layer. The data indicate substantial impacts of pollution on air quality even in this remote area. The high O values observed in 2011 may cause observable damage to the vegetation, adding stress to an ecosystem ready under the threat of desertification. [ABSTRACT FROM AUTHOR]

To prevent the fast spread of COVID-19, worldwide restrictions have been put in place, leading to a reduction in emissions from most anthropogenic sources. In this study, the impact of COVID-19 lockdowns on elemental (EC) and organic (OC) carbon was explored at a European rural background site combining different approaches: - "Horizontal approach (HA)" consists of comparing concentrations of pollutants measured at 4 m a.g.l. during pre-COVID period (2017-2019) to those measured during COVID period (2020-2021); - "Vertical approach (VA)" consists of inspecting the relationship between OC and EC measured at 4 m and those on top (230 m) of a 250 m-tall tower in Czech Republic. The HA showed that the lockdowns did not systematically result in lower concentrations of both carbonaceous fractions unlike NO 2 (25 to 36 % lower) and SO 2 (10 to 45 % lower). EC was generally lower during the lockdowns (up to 35 %), likely attributed to the traffic restrictions whereas increased OC (up to 50 %) could be attributed to enhanced emissions from the domestic heating and biomass burning during this stay-home period, but also to the enhanced concentration of SOC (up to 98 %). EC and OC were generally higher at 4 m suggesting a greater influence of local sources near the surface. Interestingly, the VA revealed a significantly enhanced correlation between EC and OC measured at 4 m and those at 230 m (R values up to 0.88 and 0.70 during lockdown 1 and 2, respectively), suggesting a stronger influence of aged and long distance transported aerosols during the lockdowns. This study reveals that lockdowns did not necessarily affect aerosol absolute concentrations but it certainly influenced their vertical distribution. Therefore, analyzing the vertical distribution can allow a better characterization of aerosol properties and sources at rural background sites, especially during a period of significantly reduced human activities., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Causal illness attributions influence how individuals cope with somatic symptoms and illnesses. Dimensions of causal symptom attributions have been examined in Western cultures with the subscale 'causes' of the revised Illness Perception Questionnaire (IPQ-R). Some previous studies have identified a stronger somatic attribution style in Asian patients. In this study it was examined if the factorial structure of causal attributions identified in Western populations can be identified in a large Chinese sample of patients presenting with somatic symptoms. We recruited 665 patients aged at least 18 who were visiting the hospital for reasons of treatment from departments of traditional Chinese medicine (TCM), neurology (Biomedicine), and psychosomatic medicine in six hospitals across China. All subjects completed the Patient Health Questionnaire (PHQ) and the causes subscale of the IPQ-R. We split the data-set by chance in two parts. On the first subsample, we conducted a confirmatory factor analysis (CFA) to check the fit of the originally proposed 4-factor structure and an exploratory factor analysis (EFA). The factor structure indentified in the EFA was rechecked with a CFA in the second subsample. The originally proposed 4-factor-model of the IPQ-R subscale causes showed no adequate fit in the first subsample. The EFA revealed two factors, psychological attributions and risk factors. The CFA in the second sample showed mediocre fit indices (RMSEA = .098, CFI = .923). For the Chinese sample we propose a two-factor structure for IPQ-R causes scale. As in other studies, we identified the relatively stable factor psychological attributions, indicating no fundamental differences in illness attributions between Western and Chinese samples.

The concentrations, size distributions, and mixing states of refractory black carbon (rBC) aerosols were measured with a ground-based Single Particle Soot Photometer (SP2), and aerosol absorption was measured with an Aethalometer at Qinghai Lake (QHL), a rural area in the Northeastern Tibetan Plateau of China in October 2011. The area was not pristine, with an average rBC mass concentration of 0.36 μg STP-m(-3) during the two-week campaign period. The rBC concentration peaked at night and reached the minimal in the afternoon. This diurnal cycle of concentration is negatively correlated with the mixed layer depth and ventilation. When air masses from the west of QHL were sampled in late afternoon to early evening, the average rBC concentration of 0.21 μg STP-m(-3) was observed, representing the rBC level in a larger Tibetan Plateau region because of the highest mixed layer depth. A lognormal primary mode with mass median diameter (MMD) of ~175 nm, and a small secondary lognormal mode with MMD of 470-500 nm of rBC were observed. Relative reduction in the secondary mode during a snow event supports recent work that suggested size dependent removal of rBC by precipitation. About 50% of the observed rBC cores were identified as thickly coated by non-BC material. A comparison of the Aethalometer and SP2 measurements suggests that non-BC species significantly affect the Aethalometer measurements in this region. A scaling factor for the Aethalometer data at a wavelength of 880 nm is therefore calculated based on the measurements, which may be used to correct other Aethalometer datasets collected in this region for a more accurate estimate of the rBC loading. The results present here significantly improve our understanding of the characteristics of rBC aerosol in the less studied Tibetan Plateau region and further highlight the size dependent removal of BC via precipitation., (Copyright © 2014 Elsevier B.V. All rights reserved.)