Two dimensional assembly of triblock Janus particles into crystal phases in the two bond per patch limit

In recent experimental work on spherical colloidal particles decorated with two hydrophobic poles separated by an electrically charged middle band (triblock Janus particles)-when particles are confined by gravity at the bottom of the sample holder-self-assembly into a Kagome two dimensional lattice has been documented [Qian Chen, Sung Chul Bae and Steve Granick, Nature, 2011, 469, 381]. Here, we assess the ability of a simple two-patch effective potential to reproduce the experimental findings. The model parameters are selected to match the experimental values, with a short-range attraction mimicking hydrophobic interactions and a patch width that allows for a maximum of two contacts per patch. We show that the effective potential is able to reproduce the observed crystallisation pathway in the Kagome structure. On the basis of free energy calculations, we also show that the Kagome lattice is stable at low temperature and low pressure, but that it transforms into a hexagonal lattice with alternating attractive and repulsive bands on increasing pressure

Diversity of Cl− Channels

Cl− channels are widely found anion pores that are regulated by a variety of signals and that play various roles. On the basis of molecular biologic findings, ligand-gated Cl− channels in synapses, cystic fibrosis transmembrane conductors (CFTRs) and ClC channel types have been established, followed by bestrophin and possibly by tweety, which encode Ca2+-activated Cl− channels. The ClC family has been shown to possess a variety of functions, including stabilization of membrane potential, excitation, cellvolume regulation, fluid transport, protein degradation in endosomal vesicles and possibly cell growth. The molecular structure of Cl− channel types varies from 1 to 12 transmembrane segments. By means of computer-based prediction, functional Cl− channels have been synthesized artificially, revealing that many possible ion pores are hidden in channel, transporter or unidentified hydrophobic membrane proteins. Thus, novel Cl−-conducting pores may be occasionally discovered, and evidence from molecular biologic studies will clarify their physiologic and pathophysiologic roles