Tetraamine Me6TREN induced monomerization of alkali metal borohydrides and aluminohydrides

Monomeric 1:1 complexes of MEH4 (M, E = Li, B, 1; Na, B, 2; Li, Al, 3; Na, Al, 4) and the tripodal tetradentate ligand (Me2NCH2CH2)3N (Me6TREN) have been prepared in good yields by refluxing in THF and allowing the solutions to cool slowly. X-ray diffraction studies show that the BH4 group binds to either Li or Na via three hydride bridges while the AlH4 group connects to Li via a single hydride bridge. Surprisingly, Me6TREN·LiAlH4 represents the first monomeric contacted ion pair LiAlH4 derivative to be structurally characterized. In every case the tetraamine coordinates via all four of its Lewis basic nitrogen atoms. A similar protocol using the alkyl-rich borohydride MBEt3H also gives monomeric species (M = Li, 5; Na, 6). All complexes have been characterized in solution by multinuclear (1H, 7Li, 11B, 13C and 27Al, where appropriate) NMR spectroscopy which reveals excellent textbook examples of 1J coupling between B/Al and H in the cases of complexes 1-4 and between B and C in the cases of complexes 5 and 6

Impacts of Subway System Modifications on Air Quality in Subway Platforms and Trains.

Subway PM₂.₅ can be substantially sourced from the operation of the system itself. Improvements in subway air quality may be possible by examining the potential to reduce these emissions. To this end, PM₂.₅ was measured on the trains and station platforms of the Toronto subway system. A comparison with previously published data for this system reveals significant changes in below ground platform PM₂.₅. A reduction of nearly one-third (ratio (95% CI): 0.69 (0.63, 0.75)) in PM₂.₅ from 2011 to 2018 appears to have resulted from a complete modernization of the rolling stock on one subway line. In contrast, below ground platform PM₂.₅ for another line increased by a factor of 1.48 (95% CI; 1.42, 1.56). This increase may be related to an increase in emergency brake applications, the resolution of which coincided with a large decrease in PM₂.₅ concentrations on that line. Finally, platform PM₂.₅ in two newly opened stations attained, within one year of operation, typical concentrations of the neighboring platforms installed in 1963. Combined, these findings suggest that the production of platform PM₂.₅ is localized and hence largely freshly emitted. Further, PM₂.₅ changed across this subway system due to changes in its operation and rolling stock. Thus, similar interventions applied intentionally may prove to be equally effective in reducing PM₂.₅. Moreover, establishing a network of platform PM₂.₅ monitors is recommended to monitor ongoing improvements and identify impacts of future system changes on subway air quality. This would result in a better understanding of the relationship between the operations and air quality of subways

Dendritic silver self-assembly in molten-carbonate membranes for efficient carbon dioxide capture

Membranes for CO2 capture should offer high permeant fluxes to keep membrane surface area small and material requirements low. Ag-supported, dual-phase, molten-carbonate membranes routinely demonstrate the highest CO2 fluxes in this class of membrane. However, using Ag as a support incurs high cost. Here, the non-equilibrium conditions of permeation were exploited to stimulate the self-assembly of a percolating, dendritic network of Ag from the molten carbonate. Multiple membrane support geometries and Ag incorporation methods were employed, demonstrating the generality of the approach, while X-ray micro-computed tomography confirmed that CO2 and O2 permeation stimulated self-assembly. We report the highest flux of Ag-supported molten-salt membranes to date (1.25 ml min−1 cm−2 at 650 °C) and ultrahigh permeability (9.4 × 10−11 mol m−1 s−1 Pa−1), surpassing the permeability requirement for economically-competitive post-combustion CO2 capture, all whilst reducing the membrane-volume-normalised demand for Ag by one order of magnitude

Nonbinary and binary transgender youth: Comparison of mental health, self-harm, suicidality, substance use and victimisation experiences

Background: Little research has compared the mental health and victimisation experiences of nonbinary youth depending on their sex assigned at birth (SAAB), or compared these two groups with binary transgender youth. Aims: To compare mental health, self-harm and suicidality, substance use and victimisation experiences between nonbinary and binary transgender young adults, both male assigned at birth (MAAB) and female assigned at birth (FAAB). Methods: Online survey data from 677 participants from the ‘Youth Chances’ community study of 16 to 25 year-olds in the United Kingdom was analysed, comparing across binary participants (transgender females (n=105) and transgender males (n=210)) and nonbinary participants (MAAB (n=93) and FAAB (n=269)). Results: Female SAAB participants (binary and nonbinary) were more likely to report a current mental health condition and history of self-harm than male SAAB participants (binary and nonbinary). Similarly, female SAAB participants (binary and nonbinary) were more likely to report childhood sexual abuse than male SAAB participants (binary and nonbinary); the reverse pattern was found for lifetime physical assault relating to being LGBTQ. Nonbinary MAAB participants were less likely than the other groups to report past suicide attempts and previous help-seeking for depression / anxiety. Binary participants reported lower life satisfaction than nonbinary participants. For all four groups, mental health problems, self-harm, suicidality, alcohol use and victimisation experiences were generally higher than that of youth in general population studies. Conclusions: These findings highlight the importance of considering both nonbinary versus binary gender identity and sex assigned at birth in relation to mental health problems, self-harm, suicidality and substance use in transgender youth. The roles of sexual abuse, other abuse and discrimination in contributing to increased rates of mental illness and self-harm in nonbinary and binary transgender individuals, particularly those who were assigned female at birth, relative to those assigned male, require investigation

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival