Molecular Composition of Oxygenated Organic Molecules and Their Contributions to Organic Aerosol in Beijing

The understanding at a molecular level of ambient secondary organic aerosol (SOA) formation is hampered by poorly constrained formation mechanisms and insufficient analytical methods. Especially in developing countries, SOA related haze is a great concern due to its significant effects on climate and human health. We present simultaneous measurements of gas-phase volatile organic compounds (VOCs), oxygenated organic molecules (OOMs), and particle-phase SOA in Beijing. We show that condensation of the measured OOMs explains 26-39% of the organic aerosol mass growth, with the contribution of OOMs to SOA enhanced during severe haze episodes. Our novel results provide a quantitative molecular connection from anthropogenic emissions to condensable organic oxidation product vapors, their concentration in particle-phase SOA, and ultimately to haze formation.Peer reviewe

Cerebral activity to opposite-sex voices reflected by event-related potentials.

Human voice is a gender discriminating cue and is important to mate selection. This study employed electrophysiological recordings to examine whether there is specific cerebral activity when presented with opposite-sex voices as compared to same-sex voices. Male voices and female voices were pseudo-randomly presented to male and female participants. In Experiment 1, participants were instructed to determine the gender of each voice. A late positivity (LP) response around 750 ms after voice onset was elicited by opposite-sex voices, as reflected by a positive deflection of the ERP to opposite-sex voices than that to same-sex voices. This LP response was prominent around parieto-occipital recording sites, and it suggests an opposite-sex specific process, which may reflect emotion- and/or reward-related cerebral activity. In Experiment 2, participants were instructed to press a key when hearing a non-voice pure tone and not give any response when they heard voice stimuli. In this task, no difference were found between the ERP to same-sex voices and that to opposite-sex voices, suggesting that the cerebral activity to opposite-sex voices may disappear without gender-related attention. These results provide significant implications on cognitive mechanisms with regard to opposite-sex specific voice processing

Impulsivity-related right superior frontal gyrus as a biomarker of internet gaming disorder

Background Internet gaming disorder (IGD) is a mental health issue that affects individuals worldwide. However, the lack of knowledge about the biomarkers associated with the development of IGD has restricted the diagnosis and treatment of this disorder.Aims We aimed to reveal the biomarkers associated with the development of IGD through resting-state brain network analysis and provide clues for the diagnosis and treatment of IGD.Methods Twenty-six patients with IGD, 23 excessive internet game users (EIUs) who recurrently played internet games but were not diagnosed with IGD and 29 healthy controls (HCs) performed delay discounting task (DDT) and Iowa gambling task (IGT). Resting-state functional magnetic resonance imaging (fMRI) data were also collected.Results Patients with IGD exhibited significantly lower hubness in the right medial orbital part of the superior frontal gyrus (ORBsupmed) than both the EIU and the HC groups. Additionally, the hubness of the right ORBsupmed was found to be positively correlated with the highest excessive internet gaming degree during the past year in the EIU group but not the IGD group; this might be the protective mechanism that prevents EIUs from becoming addicted to internet games. Moreover, the hubness of the right ORBsupmed was found to be related to the treatment outcome of patients with IGD, with higher hubness of this region indicating better recovery when undergoing forced abstinence. Further modelling analysis of the DDT and IGT showed that patients with IGD displayed higher impulsivity during the decision-making process, and impulsivity-related parameters were negatively correlated with the hubness of right ORBsupmed.Conclusions Our findings revealed that the impulsivity-related right ORBsupmed hubness could serve as a potential biomarker of IGD and provide clues for the diagnosis and treatment of IGD

Reduced loss aversion in value-based decision-making and edge-centric functional connectivity in patients with internet gaming disorder

Background and aims: Impaired value-based decision-making is a feature of substance and behavioral addictions. Loss aversion is a core of value-based decision-making and its alteration plays an important role in addiction. However, few studies explored it in internet gaming disorder patients (IGD). Methods: In this study, IGD patients (PIGD) and healthy controls (Con-PIGD) performed the Iowa gambling task (IGT), under functional magnetic resonance imaging (fMRI). We investigated group differences in loss aversion, brain functional networks of node-centric functional connectivity (nFC) and the overlapping community features of edge-centric functional connectivity (eFC) in IGT. Results: PIGD performed worse with lower average net score in IGT. The computational model results showed that PIGD significantly reduced loss aversion. There was no group difference in nFC. However, there were sig- nificant group differences in the overlapping community features of eFC 1 . Furthermore, in Con-PIGD, loss aversion was positively correlated with the edge community profile similarity of the edge 2 between left IFG and right hippocampus at right caudate. This relationship was suppressed by response con- sistency 3 in PIGD. In addition, reduced loss aversion was negatively correlated with the promoted bottom-to-up neuromodulation from the right hippocampus to the left IFG in PIGD. Discussion and conclusions: The reduced loss aversion in value-based decision making and their related edge-centric functional connectivity support that the IGD showed the same value-based decision-making deficit as the substance use and other behavioral addictive disorders. These findings may have important significance for understanding the definition and mechanism of IGD in the future

Sound waveforms.

<p>Two representative exemplars of the 9 male voices and 9 female voices were illustrated. The consonant part (/h-/) of the sound was normalized at around 40 ms in duration and the whole sound was normalized at 300 ms in duration.</p

Experimental paradigms.

<p>In Experiment 1, the 9 male voices and 9 female voices were pseudo-randomly presented to participants with equal probability. A pure tone sound was presented after each voice. Participants were instructed to press the female or male key when hearing the pure tone to indicate the gender information of the voice just before the pure tone. In Experiment 2, the 9 male voices and 9 female voices, and a pure tone stimulus were pseudo-randomly presented to participants. Participants were instructed to press the key when hearing the pure tone stimulus.</p

Grand-averaged ERP to opposite-sex voices and that to same-sex voices at electrode site PO3.

<p>In Experiment 1, the ERP to opposite-sex voices is positively deflected than that to same-sex voices at parieto-occipital recording sites (cluster <i>p</i> value = 0.014). In Experiment 2, there is no significant difference between the ERP to same-sex voices and that to opposite-sex voices. Gray bars represent the time-window (720–760 ms) centered on the peak of the difference between the ERP to same-sex voices and that to opposite-sex voices in Experiment 1. The topographies illustrate the difference between the ERP to same-sex voices and that to opposite-sex voices at the time-window (720–760 ms).</p