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Background: Major Depressive Disorder (MDD) poses a significant global health challenge, with symptom presentation potentially varying between adolescents and adults. Adolescence is a critical period marked by heightened vulnerability to interpersonal stresses, yet the impact of these stresses on the structure of depressive symptoms is not well understood. Recognizing the cultural nuances in how depression manifests among adolescents is crucial. To this end, this paper employs a network analysis approach, utilizing a comprehensive symptom checklist from the Multidimensional Depression Assessment Scale (MDAS). Our study investigates the role of interpersonal symptoms within the broader cluster of emotional, cognitive, and somatic symptoms and explores variations in adolescent groups in four Asian and European regions. Methods: We recruited a diverse sample of 6,348 adolescents aged 12 to 18 from Hong Kong, Taiwan, the UK, China, and the Netherlands using the Qualtrics platform. Employing the Gaussian Graphical Model, we established a network model of depressive symptoms as measured by the MDAS, segregating the sample into Asian and European regions to examine the interconnections between them. The study focused on identifying central symptom nodes and comparing the network structures between the two groups. Results: The analysis identified feeling worthless, low energy, being a burden to others, and low mood as central symptoms of depression. Notably, there were significant differences in the connections between depressive symptoms among Asian (Hong Kong, China and Taiwan) and European (UK and the Netherlands) adolescents, highlighting cultural variations in how interpersonal symptoms interact with emotional, cognitive, and somatic symptoms. Conclusion: This study is pioneering in applying network analysis to include interpersonal symptoms in examining depression among a diverse adolescent population. It demonstrates that interpersonal symptoms are integral to the central features of depressive symptoms. Furthermore, our findings suggest that, compared to their UK and Dutch peers, interpersonal symptoms in Asian adolescents are uniquely connected to other symptom clusters, reflecting distinct cultural patterns. Limitations: The study engaged a broad community sample; however, future research could benefit from including a larger sample size to allow for a more detailed analysis of a greater number of symptom nodes. [ABSTRACT FROM AUTHOR]

Integrated gasification combined cycle (IGCC) power generation is touted as a cost-effective technology for combining electricity generation with carbon capture. For IGCC carbon capture, membrane technology is ideally suited owing to its low energy requirements and operational simplicity. This paper describes the development of polymeric membranes for CO2 removal in IGCC plants and reviews both H2-selective and CO2-selective membranes. First, the fundamentals of CO2/H2 separation using polymeric membranes are presented along with their implications for the performances of H2-selective and CO2-selective polymers. Popular H2-selective and CO2-selective polymers that have been proposed for IGCC carbon capture are evaluated and compared. Benefits and drawbacks of each membrane type are discussed. Strategies that have resulted in improved performance are highlighted. Integrated Gasification Combined Cycle (IGCC) power plants are rapidly gaining attention as an economic way to integrate carbon capture with power generation. For IGCC carbon capture, membrane technology is ideally suited, and a number of polymeric membranes have been explored for this purpose. This review provides a well-timed update regarding the status of polymeric membranes for carbon capture from IGCC syngas. H2-selective and CO2-selective polymeric materials are critically examined and compared, with an emphasis on promising candidates such as polybenzimidazoles, polyethers and facilitated transport membranes. [ABSTRACT FROM AUTHOR]

Cerebral vascular smooth muscle cells express the C[B.sub.1] cannabinoid receptor, and C[B.sub.1] receptor agonists produce vasodilation of cerebral arteries. The purpose of this study was to determine whether vasoconstriction of rat middle cerebral artery (MCA) results in the local formation of endocannabinoids (eCBs), which, via activation of C[B.sub.1] receptors, oppose the vasoconstriction in a feedback manner. The thromboxane [A.sub.2] (TX[A.sub.2]) mimetic U-46619 significantly increased N-arachidonylethanolamine (AEA) and 2-arachidonylglycerol (2-AG) content of isolated MCA, whereas 5-hydroxytrypamine (5-HT) decreased AEA and 2-AG content. If eCBs play a feedback role in the regulation of MCA tone, then C[B.sub.1] receptor antagonists should enhance the constriction of MCA produced by U-46619 but not 5-HT. U-46619 caused concentration-dependent constrictions of endothelium-denuded MCA. Two C[B.sub.1] receptor antagonists SR-141716 and AM-251 decreased the E[C.sub.50] value for U-46619 to constrict endothelium-denuded MCA without affecting the maximal effect. A low concentration of C[B.sub.1] receptor agonist Win-55212-2 (30 nM) produced vasodilation of MCAs constricted with low but not saturating concentrations of U-46619. SR-141716 had no effect on the 5-HT concentration-contraction relationship. These data suggest that TX[A.sub.2] receptor activation increases MCA eCB content, which, via activation of C[B.sub.1] receptors, reduces the constriction produced by moderate concentrations of the TX[A.sub.2] agonist. Although 5-HT-induced vasoconstriction is reduced by exogenous C[B.sub.1] receptor agonist, activation of 5-HT receptors does not increase eCB content. These results suggest that MCA production of eCBs is not regulated by constriction per se but likely via a signaling pathway that is specific for TX[A.sub.2] receptors and not 5-HT receptors. C[B.sub.1] receptor; cannabinoids; SR-141716; AM-251; N-arachidonyleth-anolamine; 2-arachidonylglycerol; mass spectrometry