Photophysical and photoredox characteristics of a novel tricarbonyl rhenium(I) complex having an arylborane-appended aromatic diimine ligand

We report the synthesis and photophysical/photoredox characteristics of a novel tricarbonyl rhenium(I) complex having a (dimesityl)boryldurylethynyl (DBDE) group at the 4-position of a 1,10-phenanthroline (phen) ligand, [Re(CO)(3)(4-DBDE-phen)Br] (ReB). ReB in tetrahydrofuran at 298 K showed the metal-to-ligand charge transfer (MLCT) emission at around 681 nm with the lifetime (τ(em)) of 900 ns. The relatively long emission lifetime of ReB compared with that of [Re(CO)(3)(phen)Br] (RePhen, τ(em) = 390 ns) was discussed on the basis of the temperature dependent τ(em) and Franck-Condon analysis of the emission spectra of the two complexes. Emission quenching studies of both ReB and RePhen by a series of electron donors revealed that the photoinduced electron transfer (PET) quenching rate constant of ReB was faster than that of RePhen at a given Gibbs free energy change of the PET reaction (ΔG(ET)(0) > -0.5 eV). All of the results on ReB were discussed in terms of the contribution of the CT interaction between the π-orbital(s) of the aryl group(s) and the vacant p-orbital on the boron atom in DBDE to the MLCT state of the complex.     

Impaired social brain network for processing dynamic facial expressions in autism spectrum disorders

ABSTRACT: BACKGROUND: Impairment of social interaction via facial expressions represents a core clinical feature of autism spectrum disorders (ASD). However, the neural correlates of this dysfunction remain unidentified. Because this dysfunction is manifested in real-life situations, we hypothesized that the observation of dynamic, compared with static, facial expressions would reveal abnormal brain functioning in individuals with ASD. We presented dynamic and static facial expressions of fear and happiness to individuals with high-functioning ASD and to age- and sex-matched typically developing controls and recorded their brain activities using functional magnetic resonance imaging (fMRI). Result Regional analysis revealed reduced activation of several brain regions in the ASD group compared with controls in response to dynamic versus static facial expressions, including the middle temporal gyrus (MTG), fusiform gyrus, amygdala, medial prefrontal cortex, and inferior frontal gyrus (IFG). Dynamic causal modeling analyses revealed that bi-directional effective connectivity involving the primary visual cortex-MTG-IFG circuit was enhanced in response to dynamic as compared with static facial expressions in the control group. Group comparisons revealed that all these modulatory effects were weaker in the ASD group than in the control group. CONCLUSIONS: These results suggest that weak activity and connectivity of the social brain network underlie the impairment in social interaction involving dynamic facial expressions in individuals with ASD.     

On the convergence of infinite compositions of entire functions

Some trigonometric functions can be expressed by the infinite composition of polynomials. First we need to consider the convergence problem to study infinite compositions of functions. This article discusses the convergence of infinite compositions of entire functions whose constant terms are not necessarily zero.     

RASS-Enabled S/P−C and S−N Bond Formation for DEL Synthesis

DNA encoded libraries (DEL) have shown promise as a valuable technology for democratizing the hit discovery process. Although DEL provides relatively inexpensive access to libraries of unprecedented size, their production has been hampered by the idiosyncratic needs of the encoding DNA tag relegating DEL compatible chemistry to dilute aqueous environments. Recently reversible adsorption to solid support (RASS) has been demonstrated as a promising method to expand DEL reactivity using standard organic synthesis protocols. Here we demonstrate a suite of on-DNA chemistries to incorporate medicinally relevant and C−S, C−P and N−S linkages into DELs, which are underrepresented in the canonical methods.     

A Core‐Expanded Subphthalocyanine Analogue with a Significantly Distorted Conjugated Surface and Unprecedented Properties

The introduction of a seven‐membered‐ring unit in the place of a five‐membered‐ring unit in the structure of subphthalocyanine resulted in significant distortion of the bowl‐shaped structure of the conjugated molecule as well as the following unprecedented properties: the preferential formation of the axially fluoro substituted species, the fluttering‐dynamic‐motion‐induced rapid exchange of P and M enantiomers, markedly split Q‐band absorption, and a clear difference in the ring‐current effects arising from the convex and concave surfaces.     

Regulation of Telomere Length by G-Quadruplex Telomere DNA- and TERRA-Binding Protein TLS/FUS

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Highlights? TLS/FUS is identified as a G-quadruplex telomere DNA and TERRA-binding protein ? TLS binds to G-quadruplex telomere DNA and TERRA simultaneously ? The cells overexpressing TLS show gradual and progressive telomere shortening ? Overexpression of TLS results in trimethylation of histone H3 and H4 at telomere