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Understanding conical intersection (CI) dynamics and subsequent conformational changes is key for exploring and controlling photo-reactions in aromatic molecules. Monitoring of their time-resolved dynamics remains a formidable experimental challenge. In this study, we simulate the photoinduced S3 to S1 non-adiabatic dynamics of cyclooctatetraene (COT), involving multiple CIs with relaxation times in good agreement with experiment. We further investigate the possibility to directly probe the CI passages in COT by off-resonant X-ray Raman spectroscopy (TRUECARS) and time-resolved X-ray diffraction (TRXD). We find that these signals sensitively monitor key chemical features during the ultrafast dynamics. First, we distinguish two CIs by using TRUECARS signals with their appearances at different Raman shifts. Second, we demonstrate that TRXD, where X-ray photons scatter off electron densities, can resolve ultrafast changes in the aromaticity of COT. It can further distinguish between planar and non-planar geometries explored during the dynamics, as e.g. two different tetraradical-type CIs. The knowledge gained from these measurements can give unique insight into fundamental chemical properties that dynamically change during non-adiabatic passages.

Autism spectrum disorder is considered a vulnerability for many diseases including coronavirus disease 2019. This study investigated trends in coronavirus disease 2019 among children and adolescents with and without autism spectrum disorder and to evaluate whether there are differences in the prevalence, severity, and case fatality rate. We used data from the National Health Insurance Service for all people [greater than or equal to] 19 years of age. Among 9,187,211 children and adolescents [greater than or equal to] 19 years of age, 402,499 (4.4%) were coronavirus disease 2019-positive. Of the total population, 63,054 (0.7%) were diagnosed with autism spectrum disorder, among whom 2557 (4.1%) were coronavirus disease 2019-positive. The coronavirus disease 2019 prevalence was lower among children and adolescents with autism spectrum disorder, with 4055 per 100,000 versus 4383 per 100,000 without autism spectrum disorder (p < 0.001). However, children and adolescents with autism spectrum disorder exhibited a higher proportion of hospitalization (24.8% vs 21.5%) and severe disease (0.2% vs 0.01%) than those without autism spectrum disorder (p < 0.001); the length of hospital stay among inpatients was not different between the two groups (9.5 vs 9.4 days, respectively; p = 0.48). There were six deaths in total, with no deaths among children and adolescents with autism spectrum disorder. The quarantine policies have played a great role in sustaining low prevalence and higher hospitalization rates among children and adolescents with autism spectrum disorder.

The skyrocketing single-plastic demand during the coronavirus disease 2019 (COVID-19) pandemic proved the limitation of top-down environmental policies in accomplishing sustainable consumption and waste management. Nevertheless, 'smart consumers' can make smart choices for sustainable development. However, a review of the South Korean environmental education curriculum reveals that the current structure heavily leans towards the elementary level and does not enlighten the public on 'what' and 'how' to live sustainably. This study uses a quick survey to suggest that the effectiveness of environmental education may be enhanced if: (1) guidance on how to live with the natural environment in harmony for collective cooperation towards resilient and sustainable community building is incorporated with a clear purpose, (2) environment-friendly culture-building activities are enforced to institutionalise a new paradigm of sustainability to replace today's consumerism, and (3) contents are updated regularly to include Earth and environmental science knowledge in the state of art.

Histidine state (protonated or δ or ε tautomer) has been considered the origin of abnormal misfolding and aggregation of β-amyloid (Aβ). Our previous studies reported that the δδδ isomer of Aβ (1-40) has a greater propensity for β-sheet conformation compared to other isomers. However, direct proof of the tautomeric effect has not been reported. In this context, we calculated histidine site-specific two-dimensional infrared spectroscopy of the δδδ, εεε, and πππ (all protonated histidine) systems within the framework of classical molecular dynamics simulations aiming at connecting our previous results with the current experimental observations. Our results showed that β-sheet formation is favored for the δδδ and πππ tautomers compared with the εεε tautomer, consistent with our previous studies. This result was further supported by contact map analyses and the strength of dipole coupling between the amide-I bonds of each residue. The two-dimensional infrared diagonal trace for each tautomer included three distinctive spectrally resolvable peaks near 1680, 1686, and 1693 cm-1, as was also observed for histidine dipeptides. However, the peak positions at His6, His13, and His14 did not show a consensus trend with the histidine or protonation state but were instead affected by the presence of surrounding hydrogen bonds. Our study provides a deeper insight into the influence of tautomerism and protonation of histidine residues in Aβ (1-40) on amyloid misfolding and provides a connection between our previous simulations and experimental observations.

Third order polarizability, (γ) taken from the collective electronic oscillator (CEO) method was used to calculate the two-photon absorption (TPA) of tetrastyryl-[2,2]paracyclophane derivatives with different through-space charge transfer configurations considering various donor and acceptor combinations at the terminal styryl groups. For the virtually same linear absorption, different TPA spectra were obtained. For controlling and fine-tuning frequency and cross-sections of TPA the through-space charge transfer interactions can be used. The results are explained by the electronic density matrices corresponding to governing oscillators in one- and two-photon absorption and the ground state. It is indicated that for the studied systems mainly the lowest four oscillators are responsible for the TPA cross-sections rather than a simple effective three-state model.

The symptoms, incidence, and risk for complications of coronavirus disease (COVID-19) remain controversial. Several types of long COVID, meaning prolonged symptoms or long-term complications of COVID-19, have been reported (1). [...]