In urban areas, variations in the functional usage of buildings or their clusters directly influence the 2D/3D morphology of buildings which can lead to changes in the ventilation potential (VP) at different heights, but there is a lack of refined quantitative relationship analysis between 3D building form parameters (BFPs) and VP at different heights within a certain urban area. The objective of our study is to obtain simulated wind field data from different heights, considering distances from roads, and transverse and longitudinal sections. We employ partial correlation analysis, simple correlation analysis, and Geographic detectors to uncover the extent and mechanisms of the influence of BFPs on the ventilation effectiveness of neighborhoods in a major urban center in China, specifically Nanjing. The findings demonstrate that, at all heights, there is an inverse relationship between wind speed and building density (BD), with the location of higher wind speed generally aligning with the intersection points. The correlation coefficients between BD and simulated wind speed are 0.040 (1.5 m), −0.475 (10 m), and −0.314 (30 m), while the correlation coefficients between building height (BH) and simulated wind speed are 0.237. However, no significant correlation is observed between floor area ratio (FAR) and simulated wind speed. Geographic detector analysis reveals differences in the correlation between BFPs and simulated wind speed at different heights within various building functional areas. Our study provides some practical information for urban planners and designers to carry out wind sensitivity and adaptation planning and urban design.
Aldehydes are common air pollutants with carcinogenicity. Genotoxicity of single aldehyde has been studied well, but the combined genotoxicity is rarely known. Here, we evaluated the combined genotoxicity of formaldehyde and acrolein on BEAS-2B cells in terms of DNA strands breakage, chromosome damage and gene mutation below subcytotoxic concentrations covering smoking-related concentrations. Meanwhile, the molecular mechanism was investigated further based on oxidative stress, DNA-protein crosslinks (DPCs), cell cycle and DNA damage-repair pathway. Co-exposure to formaldehyde and acrolein mixtures showed significantly synergistic interaction on DNA strands breakage and chromosome damage in a concentration/time-dependent manner, while antagonism was shown on the late genotoxic endpoints (e.g. cytoplasmic block micronucleus (CBMN) and HPRT gene mutation). Moreover, formaldehyde synergistically potentiated acrolein-induced S-phase arrest, inhibition of DNA repair and up-regulation of genes related to cell stress, which conversely strengtherned mixture-induced DNA/chromosome damage and finally resulted in antagonism on late genotoxic events. Additionally, formaldehyde-induced DNA damage mainly resulted from the direct covalent bonding (e.g. DPCs), while acrolein-induced DNA damage mainly generated from oxidative damage (e.g. oxidative stress), which dominated the synergistic DNA strand breakage induced by mixtures. Summarily, aldehyde mixtures (formaldehyde and acrolein) induced multiplex combined genotoxicity on BEAS-2B cells even at smoking-related concentrations, which was dependent on genotoxic endpoints and closely related to that formaldehyde potentiated acrolein-induced cell stress, S-phase arrest and inhibition of DNA repair. So prolonged exposure to aldehyde mixtures may have a more serious risk to respiratory system in animal and human than the expectation based on the toxicity of single aldehyde even at environmentally relevant concentrations.
A stable isotope dilution liquid chromatography tandem mass spectrometry method for the analysis of 16 polycyclic aromatic hydrocarbons in cigarette smoke condensate was developed and validated. Compared with previously reported methods, this method has lower limits of detection (0.04-1.35 ng/cig). Additionally, the proposed method saves time, reduces the number of separation steps, and reduces the quantity of solvent needed. The new method was applied to evaluate polycyclic aromatic hydrocarbon content in 213 commercially available cigarettes in China, under the International Standardization Organization smoking regime and the Health Canadian intense smoking regime. The results showed that the total polycyclic aromatic hydrocarbon content was more than two times higher in samples from the Health Canadian intense smoking regime than in samples from the International Standardization Organization smoking regime (1189.23 versus 2859.50 ng/cig, p < 0.05). Meanwhile, the concentration of individual polycyclic aromatic hydrocarbons (and total polycyclic aromatic hydrocarbons) increased with labeled tar content in both of the tested smoking regimes. There was a positive correlation between total polycyclic aromatic hydrocarbons under the International Standardization Organization smoking regime with that under the Health Canadian intense smoking regime. The proposed liquid chromatography tandem mass spectrometry method is satisfactory for the rapid, sensitive, and accurate quantitative evaluation of polycyclic aromatic hydrocarbon content in cigarette smoke condensate, and it can be applied to assess potential health risks from smoking.
Despite the growing awareness of academic fraud, its prevalence in the field of neurology has not been fully assessed. This review aims to analyze the characteristics of the retracted papers in the field of neurology and the reasons for the retraction to better understand the trends in this area and to assist to avoid retraction incidents.A total of 79 papers were included, which pertained to 22 countries and 64 journals. The marking methods for retracting original papers included watermarks (89.04%), retracted signs in the text (5.48%) and no prompt (5.48%). The median M (interquartile range [IQR]) of citations in retractions in neurology was 7 (41). Studies continued to be cited after retraction with an M (IQR) of 3 (16). The journal impact factor was between 0 and 157.335, with an M (IQR) of 5.127 (3.668). 45.21% and 31.51% papers were mainly published in the first and second quartile journals, respectively. The M (IQR) time elapsed between publication and retraction was 32 (44) months. The reasons for retraction included two major categories, academic misconduct (79.75%) and academic unintentional mistakes (20.25%).The number of retractions in neurology has been on the rise over the past decade, with fabricated academic misconduct being the main cause of the retractions. Due to the long time lag between publication and retraction, a number of unreliable findings continue to be cited following retraction. In addition to the requisite standards of academic ethics, augmenting research training and fostering interdisciplinary collaboration are crucial in enhancing research integrity.
Although rivers are one of the dominant pathways by which microplastics reach the oceans, reports on remote rivers are rare. Dafeng River is located in Guangxi Province, China, is an important water source and a habitat of a coastal dolphin, Sousa chinensis, which is a first-class national protected animal in China. In this study, we determined the distribution and characteristics of microplastics in the surface water, sediment, and fish of the river. During the dry and rainy seasons, the microplastics content of the surface water ranged from 3 × 10
While impervious surface expands with global urbanization, understanding the quality and quantity changes of soil organic carbon (SOC) under impervious surfaces is essential to assess the impacts of urbanization on the SOC pool and cycling. By comparing soils under impervious surfaces with surface and subsurface soils from adjoining open areas, we present a systematic study on the SOC signature under impervious surfaces. SOC concentration barely changed when comparing soils under impervious surfaces with subsurface soil from the nearby open area; however, the depletion on SOC was 35–62% when it was compared with surface soils. Regardless of comparison with surface or subsurface soils, bulk-level 13C NMR spectra and specific molecular biomarkers showed a depletion in carbohydrates and an increase in aromatics in SOC composition. Such an alteration was greater with coverage by concrete slabs than simulated home structures built on crawl spaces and was greater as the coverage duration of residential home structures increased. Long-term coverage of residential home structures suppressed microbial degradation and selectively increased the sequestration of plant suberin- and lignin-derived carbon, which would likely increase the residence time of SOC. This study highlights a possible impact of urbanization on the SOC signature and emphasizes that biogeochemical impacts on SOC vary with the type of impervious surface and coverage time.