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Research on individual level polycyclic aromatic hydrocarbons (PAHs) exposure is scarce. Moreover, the independent contribution of ambient‐ and indoor‐origin PAHs to personal exposure remains poorly studied. We performed simultaneous ambient, residential indoor, and personal exposure measurements in a panel of healthy adults to investigate particle‐bound PAHs, focusing on their carcinogenic congeners (cPAHs). Average PAH concentrations were much higher in ambient and residential indoor than personal exposure, with distinct seasonal variations. We employed chrysene as a tracer to investigate residential indoor and personal PAHs exposure by origin. Personal cPAH exposure was largely attributable to ambient‐origin exposures (95.8%), whereas a considerable proportion of residential indoor PAHs was likely attributable to indoor emissions (33.8%). Benzo[a]pyrene equivalent (BaPeq) concentrations of cPAH accounted for 95.2%‒95.6% of total carcinogenic potential. Uncertainties in estimated PAHs (and BaPeq) exposure and cancer risks for adults were calculated using the Monte Carlo simulation. Cancer risks attributable to ambient, residential indoor, and personal cPAH inhalation exposures ranged from 4.0 × 10−6 to 1.0 × 10−5. A time‐activity weighted model was employed for personal PAH exposure estimations. Estimated cPAH exposures demonstrate high cancer risks for adults in Hong Kong, suggesting that exposure to indoor‐generated PAHs should be of great concern to the general population. [ABSTRACT FROM AUTHOR]

Despite emerging literature on the effects of cross‐border ties on international immigration's mental health, research concerning China's internal migrants' mental health remains scarce. After 40 years of China's "one‐child policy," new‐generation migrants (born after 1980) have been found to have poorer mental health status. With smaller family structures, previous studies found that new‐generation migrants are more likely to be affected by migration‐related stresses, with social ties having mixed effects on their mental health. In this paper, we examine the effects of local ties (in host cities) and trans‐local ties (in the migrants' original home location) on China's rural and urban migrants' mental health by using a national‐level survey data comprising N = 16,000 participants. We focus on whether these relationships vary among the four categories of migrants—grouped according to their place of origin and date of birth. The study results show that both local and trans‐local "kinship" ties have positive effects on migrants' mental health, whereas participation in organisation or activities have negative effects. In addition, new‐generation migrants were found to have relatively poor mental health, being more easily affected by trans‐local kinship ties. Moreover, participation in local activities had more significant adverse influence on interprovincial floating migrants, who had poorer mental health than the intraprovincial group. The study deciphered underlying negative health consequences attributed to the one‐child policy and calls for intraprovincial mobility with local urbanisation. The study concludes that social integration of new‐generation migrants can act as a protective intervention aimed at enhancing the mental capital of Chinese cities. [ABSTRACT FROM AUTHOR]

Recent studies indicate a causative relationship between defects in autophagy and dopaminergic neuron degeneration in Parkinson disease (PD). However, it is not fully understood how autophagy is regulated in the context of PD. Here we identify USP24 (ubiquitin specific peptidase 24), a gene located in the PARK10 (Parkinson disease 10 [susceptibility]) locus associated with late onset PD, as a novel negative regulator of autophagy. Our data indicate that USP24 regulates autophagy by affecting ubiquitination and stability of the ULK1 protein. Knockdown of USP24 in cell lines and in human induced-pluripotent stem cells (iPSC) differentiated into dopaminergic neurons resulted in elevated ULK1 protein levels and increased autophagy flux in a manner independent of MTORC1 but dependent on the class III phosphatidylinositol 3-kinase (PtdIns3K) activity. Surprisingly, USP24 knockdown also improved neurite extension and/or maintenance in aged iPSC-derived dopaminergic neurons. Furthermore, we observed elevated levels of USP24 in the substantia nigra of a subpopulation of idiopathic PD patients, suggesting that USP24 may negatively regulate autophagy in PD. Abbreviations: Bafilomycin/BafA: bafilomycin A1; DUB: deubiquitinating enzyme; iPSC: induced pluripotent stem cells; MTOR: mechanistic target of rapamycin kinase; MTORC1: MTOR complex 1; nt: non-targeting; PD: Parkinson disease; p-ATG13: phospho-ATG13; PtdIns3P: phosphatidylinositol 3-phosphate; RPS6: ribosomal protein S6; SNPs: single nucleotide polymorphisms; TH: tyrosine hydroxylase; USP24: ubiquitin specific peptidase 24 [ABSTRACT FROM AUTHOR]

Built environment factors, especially street-scale design and traffic casualties, are intrinsically interlinked. Starting from Alker Tripp's seminal ideas about city design, street morphology, and accident risk, this article summarizes results from an increasingly sophisticated line of enquiry at the boundaries between transport geography, network modeling, urban geography, and planning. It goes on to specify what we believe to be the most comprehensive study yet, based on five years' worth of road casualty data from London; GIS data on street morphology and physical features captured at a street-link unit of analysis; socio-economics and other determinants of accidents; and individual data about casualty victims. We test hypotheses about links between urban morphology and casualty severity using multi-level models with individual victim attributes at level-one, street-link morphology attributes (various measure of network connectivity) at level-two, and neighborhood descriptors at level-three. Results indicate that street-level morphology and design (expressed in terms of betweenness, divergence ratio, and hull radius), together with traffic volume and physical features of streets are all significantly associated with odds of “Killed and Seriously Injured” (KSI) causality incidents. We find the strongest evidence yet recorded that London's 20-MPH speed-restricted residential zones reduce the incidence of KSI; while neighborhood-level factors such as population density, deprivation of living environment, and access to services are also significant predictors of KSI indicating that selective urban territorial enclosure can save lives. [ABSTRACT FROM AUTHOR]

Background Using UK Biobank data, this study sought to explain the causal relationship between alcohol intake and cognitive decline in middle and older aged populations. Methods Data from 13 342 men and women, aged between 40 and 73 years were used in regression analysis that tested the functional relationship and impact of alcohol on cognitive performance. Performance was measured using mean reaction time (RT) and intra-individual variation (IIV) in RT, collected in response to a perceptual matching task. Covariates included body mass index, physical activity, tobacco use, socioeconomic status, education and baseline cognitive function. Results A restricted cubic spline regression with three knots showed how the linear (β 1 = −0.048, 95% CI: −0.105 to −0.030) and non-linear effects (β 2 = 0.035, 95% CI: 0.007–0.059) of alcohol use on mean RT and IIV in RT (β 1 = −0.055, 95% CI: −0.125 to −0.034; β 2 = 0.034, 95% CI: 0.002–0.064) were significant adjusting for covariates. Cognitive function declined as alcohol use increased beyond 10 g/day. Decline was more apparent as age increased. Conclusions The relationship between alcohol use and cognitive function is non-linear. Consuming more than one UK standard unit of alcohol per day is detrimental to cognitive performance and is more pronounced in older populations. [ABSTRACT FROM AUTHOR]