Electroneutrality Breakdown and Specific Ion Effects in Nanoconfined Aqueous Electrolytes Observed by NMR

Ion distribution in aqueous electrolytes near the interface plays critical roles in electrochemical, biological and colloidal systems and is expected to be particularly significant inside nanoconfined regions. Electroneutrality of the total charge inside nanoconfined regions is commonly assumed a priori in solving ion distribution of aqueous electrolytes nanoconfined by uncharged hydrophobic surfaces with no direct experimental validation. Here, we use a quantitative nuclear magnetic resonance approach to investigate the properties of aqueous electrolytes nanoconfined in graphitic-like nanoporous carbon. Substantial electroneutrality breakdown in nanoconfined regions and very asymmetric responses of cations and anions to the charging of nanoconfining surfaces are observed. The electroneutrality breakdown is shown to depend strongly on the propensity of anions toward the water-carbon interface and such ion-specific response follows generally the anion ranking of the Hofmeister series. The experimental observations are further supported by numerical evaluation using the generalized Poisson-Boltzmann equationComment: 26 pages, 3 figure

Media coverage of stand your ground laws deters crime in some cities, but not in others

So-called ‘stand your ground laws’ – which give people the right to use deadly force to defend themselves – have now been in place for a decade. In new research which uses a Texas shooting incident as a case study, Ling Ren, Yan Zhang, and Jihong “Solomon” Zhao examine whether or not the publicity over shooting incidents where the law is invoked helps to deter crime – specifically residential and business burglaries. They find that such media coverage of high-profile incidents does have a deterrent effect in some nearby cities, but not in others

Intramolecular Torque, an Indicator of the Internal Rotation Direction of Rotor Molecules and Similar Systems

Torque is ubiquitous in many molecular systems, including collisions, chemical reactions, vibrations, electronic excitations and especially rotor molecules. We present a straightforward theoretical method based on forces acting on atoms and obtained from atomistic quantum mechanics calculations, to quickly and qualitatively determine whether a molecule or sub-unit thereof has a tendency to rotation and, if so, around which axis and in which sense: clockwise or counterclockwise. The method also indicates which atoms, if any, are predominant in causing the rotation. Our computational approach can in general efficiently provide insights into the rotational ability of many molecules and help to theoretically screen or modify them in advance of experiments or before analyzing their rotational behavior in more detail with more extensive computations guided by the results from the torque approach. As an example, we demonstrate the effectiveness of the approach using a specific light-driven molecular rotary motor which was successfully synthesized and analyzed in prior experiments and simulations.Comment: 11 pages, 4 figures, 1 SI fil

Tetra­kis(1-allyl-1H-imidazole-κN 3)bis­(thio­cyanato-κN)manganese(II)

The structure of the title compound, [Mn(NCS)2(C6H8N2)4], consists of isolated mol­ecules of [Mn(NCS)2(Aim)4] (Aim = 1-allyl­imidazole), which contain a compressed octa­hedral MnN6 chromophore (site symmetry ). The NCS− anions are trans and four N atoms from the Aim ligands define the equatorial plane. The mean Mn—N(Aim) and Mn—N(NCS) distances are 2.270 and 2.229 Å, respectively. Weak C—H⋯N inter­actions contribute to the crystal packing stability

Connexin26 Gap Junction Mediates miRNA Intercellular Genetic Communication in the Cochlea and Is Required for Inner Ear Development

Organ development requires well-established intercellular communication to coordinate cell proliferations and differentiations. MicroRNAs (miRNAs) are small, non-coding RNAs that can broadly regulate gene expression and play a critical role in the organ development. In this study, we found that miRNAs could pass through gap junctions between native cochlear supporting cells to play a role in the cochlear development. Connexin26 (Cx26) and Cx30 are predominant isoforms and co-express in the cochlea. Cx26 deficiency but not Cx30 deficiency can cause cochlear developmental disorders. We found that associated with Cx26 deletion induced the cochlear developmental disorders, deletion of Cx26 but not Cx30 disrupted miRNA intercellular transfer in the cochlea, although inner ear gap junctions still retained permeability after deletion of Cx26. Moreover, we found that deletion of Cx26 but not Cx30 reduced miR-96 expression in the cochlea during postnatal development. The reduction is associated with the cochlear tunnel developmental disorder in Cx26 knockout (KO) mice. These data reveal that Cx26-mediated intercellular communication is required for cochlear development and that deficiency of Cx26 can impair miRNA-mediated intercellular genetic communication in the cochlea, which may lead to cochlear developmental disorders and eventually congenital deafness as previously reported