Solvent effects on the intramolecular charge transfer excited state of 3CzClIPN: a broadband transient absorption study.

The prediction of solvent properties using molecular probes often relies on correlating steady-state absorption and fluorescence measurements, as well as determining absorption maxima and/or Stokes shifts. In this study, we employ femtosecond broadband transient absorption (fs-bb-TA) spectroscopy to investigate the spectroscopic behaviour of the intramolecular charge transfer (ICT) excited state of 3CzClIPN (2,4,6-tri(9H-carbazol-9-yl)-5-chloroisophthalonitrile), a representative ICT organic molecule, in both aromatic and non-aromatic solvents. Unlike observations in non-aromatic media, fs-bb-TA spectra of 3CzClIPN in aromatic solvents exhibit enhanced spectral broadening that strongly correlates with the solvent's polarity. We hypothesise that this spectral broadening originates from a wider configurational energy landscape experienced by the positively charged carbazole Cz+ group, owing to the larger size and, consequently, reduced solvation effectiveness of aromatic solvent molecules.

Effects of traditional Chinese exercise on cognitive and psychological outcomes in older adults with mild cognitive impairment: A systematic review and meta-analysis.

BACKGROUND: Mild cognitive impairment (MCI) can be a stage of pre-dementia. Although the traditional Chinese exercise (TCE) has benefits associated with cognitive functions, the effects of the TCE on cognitive functions of older patients with MCI remain controversial. This study performs a meta-analysis to quantify the efficiency of TCE for older individuals on cognitive and psychological outcomes. METHODS: A comprehensive database search was conducted on PubMed, Embase, the Cochrane Central Register of Controlled Trials (CENTRAL), CINAHL (EBSCO), Web of Science, and four Chinese medical databases. We included trials published up to April 22, 2018, that fulfilled our inclusion and exclusion criteria. The literature was screened, the data were extracted and the methodological quality of the included trials was assessed. Meta-analyses were performed on the included data. RESULTS: A total of 803 patients from 5 trials were included in our meta-analysis. Overall, there were no significant differences in global cognitive functions (P = .06), memory (P = .11), executive function (P = .74), Verbal fluency (P = .45) and depression (P = .89) between the TCE and the control groups. However, the TCE significantly improved the visuospatial function (SMD = 0.38, 95% CI = 0.22 to 0.54; P < .001) for individuals with MCI. CONCLUSIONS: The findings of this study suggested that the TCE was associated with significant improvement in visuospatial function but did not affect the global cognitive functions, depression and other specific cognitive domains. There is a lack of clear evidence for effects of TCE; further large, rigorously designed studies are needed.