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Graphdiyne-based nanotubes (GDNTs) are a novel type of carbon nanotubes. While conventional carbon nanotubes (CNTs) aregenerated by rolling graphene sheets, GDNTs are generated by rolling sheets that are similar to graphene but where the edges areelongated by the introduction of additional acetylene bonds between vertices (C6 aromatic rings). Such nanotubes are predicted tohave many useful practical applications, but a thorough understanding of the relationship between their structure and theirphysical properties is still missing. We present a theoretical study of the electronic and optical properties of GDNTs. Thestructural, electronic, and optical properties of GDNTs with different diameters (i.e., 2–10 additional acetylene bonds) havebeen studied systematically by using density function theory (DFT) and self-consistent charge density functional tight-binding(SCC-DFTB) and by solving the Bethe–Salpeter equation (BSE), with and without considering the electron-hole interactions.The results indicate that the GDNTs are semiconductors with the direct band gap in close range, which is beneficial forphotoelectronic devices and applications. Moreover, the absorption spectra of the GDNTs with different edge structures, (armchair,and zigzag) revealed little differences between the optical spectra of armchair and zigzag GDNTs, which could mean thatfine separation between those structures (a process that is likely difficult and expensive in practice) will not be necessary.Importantly, the nanotubes were highly stable based on their cohesive energies, and their exciton binding energies were as largeas about ~ 1 eV. From a methodological point of view, SCC-DFTB was found to be in agreement with more elaborate DFTcalculations for most systems., Correction published in: Houshmand, F., Friedman, R., Jalili, S. et al. Correction to: Exciton effect in new generation of carbon nanotubes: graphdiyne nanotubes. J Mol Model 29, 61 (2023). https://doi.org/10.1007/s00894-023-05456-0

The treatment gap for people with mental disorders exceeds 50% in all countries of the world, approaching astonishingly high rates of 90% in the least resourced countries. We report the findings of the first systematic survey of leaders of psychiatry in nearly 60 countries on the strategies for reducing the treatment gap. We sought to elicit the views of these representatives on the roles of different human resources and health care settings in delivering care and on the importance of a range of strategies to increase the coverage of evidence-based treatments for priority mental disorders for each demographic stage (childhood, adolescence, adulthood and old age). Our findings clearly indicate three strategies for reducing the treatment gap: increasing the numbers of psychiatrists and other mental health professionals; increasing the involvement of a range of appropriately trained non-specialist providers; and the active involvement of people affected by mental disorders. This is true for both high income and low/middle income countries, though relatively of more importance in the latter. We view this survey as a critically important first step in ascertaining the position of psychiatrists, one of the most influential stakeholder communities in global mental health, in addressing the global challenge of scaling up mental health services to reduce the treatment gap

Alterations in the expression and signalling pathways of vascular endothelial growth factor (VEGF) have been linked to the clinical features and pathogenesis of hematologic malignancies. In this study, we showed that VEGF protein expression was statistically significantly higher in the leukemic blasts than in the normal hematopoietic counterparts. A statistically significant correlation between expression of VEGF and p27(Kip1) was observed in bone marrows from 42 patients with acute myeloid leukemia (P<0.001). We further demonstrated that forced VEGF overexpression or autocrine VEGF stimulation of VEGFR-2 triggers proliferation and migration/invasion of U-937 leukemic cells, thereby inducing a more invasive tumor phenotype. U-937 cells overexpressing VEGF were resistant to all-trans-retinoic acid-(ATRA) or camptothecin-induced apoptosis. Finally, we showed that increased p27(Kip1) expression enhanced the ability of VEGF and VEGFR-2 to promote the migration of U-937 cells. Taken together, our results suggest that elevated level of VEGF may contribute to the adverse patient outcome by promoting cell growth, survival and migration of leukemic cells and by reducing the sensitivity of leukemic cells to therapeutic agents-induced apoptosis.