Influence of Voltage Rate on the Diffusion of Organic Ions Through Bilayer Lipid Membranes

Tetraphenylphosphonium chloride(TPP) and Sodium Tetraphenylborate(TPB) are organic ions that are able to passively move across the membrane down the electrochemical gradient. To further investigate the transport of organic ions through the lipid partition of a membrane, we employed artificial planar bilayer membrane bathed by electrolyte solutions. The bilayer membrane integrity was assessed from capacitance and conductance measurements. Changes in membrane permeability upon organic ion addition were monitored by recording the ionic currents in response to variable voltage ramps. Besides expected changes in membrane permeability we observed that the linearity of the I-V plots is strongly influenced by the rate of the voltage change. This is a good indication that the transmembrane transport is a diffusion limited process. In conclusion, these ions are good experimental models for helping us understand similar ionic transport processes through biological membranes

The relation between people's connection with a target and the perceived importance of justice

We propose that actors will perceive justice as more important with respect to a target when they experience moderate versus extremely high or extremely low connection with the target. In two studies, we manipulated actors’ connection with (e.g., similarity to) a target and the target's standing on the appropriate justice criterion. Both studies yielded the predicted curvilinear relation between connectedness and the perceived relevance of justice. In Study 2, actors’ decisions were more affected by the justice criterion in the moderate versus extreme connectedness conditions. Our findings have important implications for the interplay between connection with others and moral motivations

Steric Hindrance of Photoswitching in Self-Assembled Monolayers of Azobenzene and Alkane Thiols

Surface-bound azobenzenes exhibit reversible photoswitching via trans–cis photoisomerization and have been proposed for a variety of applications such as photowritable optical media, liquid crystal displays, molecular electronics, and smart wetting surfaces. We report a novel synthetic route using simple protection chemistry to form azobenzene-functionalized SAMs on gold and present a mechanistic study of the molecular order, orientation, and conformation in these self-assembled monolayers (SAMs). We use vibrational sum-frequency generation (VSFG) to characterize their vibrational modes, molecular orientation, and photoisomerization kinetics. Trans–cis conformational change of azobenzene leads to the change in the orientation of the nitrile marker group detected by VSFG. Mixed SAMs of azobenzene and alkane thiols are used to investigate the steric hindrance effects. While 100% azobenzene SAMs do not exhibit photoisomerization due to tight packing, we observe reversible switching (>10 cycles) in mixed SAMs with only 34% and 50% of alkane thiol spacers

The Relation Between People's Connection With a Target and the Perceived Importance of Justice

We propose that actors will perceive justice as more important with respect to a target when they experience moderate versus extremely high or extremely low connection with the target. In two studies, we manipulated actors’ connection with (e.g., similarity to) a target and the target's standing on the appropriate justice criterion. Both studies yielded the predicted curvilinear relation between connectedness and the perceived relevance of justice. In Study 2, actors’ decisions were more affected by the justice criterion in the moderate versus extreme connectedness conditions. Our findings have important implications for the interplay between connection with others and moral motivations