Inclusion properties of volatile organic compounds in a calixarene-based organic zeolite

The inclusion properties of a calixarene-based porous material have been studied to investigate the adsorption and the desorption of carbon tetrachloride, chloroform, and water in the zeolite-like structure. Uptake and release processes have been studied both by time-resolved powder X-ray diffraction and by thermogravimetric analysis to obtain structural and kinetic information. The selected guests are able to enter the structure with an increase in the host cell volume and with time-dependent diffusivity coefficients. Chloroform molecules act as a permanent porosity switch promoting a phase transition to non-porous triclinic form.

Biological Motion Perception in Autism

Typically developing adults can readily recognize human actions, even when conveyed to them via point-like markers placed on the body of the actor (Johansson, 1973). Previous research has suggested that children affected by autism spectrum disorder (ASD) are not equally sensitive to this type of visual information (Blake et al, 2003), but it remains unknown why ASD would impact the ability to perceive biological motion. We present evidence which looks at how adolescents and adults with autism are affected by specific factors which are important in biological motion perception, such as (eg, inter-agent synchronicity, upright/inverted, etc).

Global Properties of Natural Scenes Shape Local Properties of Human Edge Detectors

Visual cortex analyzes images by first extracting relevant details (eg, edges) via a large array of specialized detectors. The resulting edge map is then relayed to a processing pipeline, the final goal of which is to attribute meaning to the scene. As this process unfolds, does the global interpretation of the image affect how local feature detectors operate? The results show that some aspects of local processing were significantly affected by scene manipulations that were specifically probing the higher-level semantic interpretation of the scene. It may therefore be inaccurate to regard early feature detectors as operating completely outside the domain of higher-level vision.

Internal Noise for Choosing Items is Affected by Their Number and Spatial Arrangement

We studied whether, when choosing an item out of n items, the internal noise associated with making this choice is affected by the number of items and/or their spatial arrangement. Each item is represented by a patch of Gabor segments with different orientations; the task is to identify the patch with vertical orientation. The patches are positioned around the clock, and some spatial jitter is applied to each patch. We found an increase in internal noise with the number of patches. Jitter causes higher internal noise compared with no jitter, but different jitter configurations do not affect internal noise.

Sequence stereoisomerism in calixarene-based pseudo[3]rotaxanes

Two calix[6]arene directional wheels can be ordered in the right stereosequence by their through-the-annulus threading with a rationally designed bis(benzylalkylammonium) axle. These stereoisomeric pseudo[3]rotaxanes can be considered as a minimal "informational system" because the "written information" on the thread is transferred to a specific sequence stereoisomer.

Absolute configuration assignment of inherently chiral calix[4]arenes using DFT calculations of chiroptical properties

The racemate of an inherently chiral meta-substituted calix[4]arene derivative 3 has been resolved via enantioselective HPLC. Measured optical rotation dispersion and electronic circular dichroism have been compared with DFT theoretical predictions. The comparison indicates that the absolute configuration of the dextrorotatory enantiomer (+)-3 is cS. The procedure has been successfully tested against a literature precedent confirming the validity of the method.