Fluorous ligand capture (FLC): a chemoselective solution-phase strategy for isolating 99mTc-labelled compounds in high effective specific activity

A new approach for preparing (99m)Tc-labelled compounds in high effective specific activity was developed by utilizing a novel fluorous ligand capture (FLC) agent and a chemoselective filtration strategy. This paradigm eliminates the need to use HPLC to obtain technetium(I) based molecular imaging probes free from residual precursor.     

Facile and unified approach to skeletally diverse, privileged scaffolds

A novel strategy has been developed to generate a diverse array of privileged scaffolds from readily available tetrahydropyridine precursors that may be prepared by a multicomponent assembly process followed by a ring-closing metathesis. The functionality embedded in these key intermediates enables their facile elaboration into more complex structures of biological relevance by a variety of ring-forming processes and refunctionalizations.     

Microtechnology: meet neurobiology

The field of neuroscience has always been attractive to engineers. Neurons and their connections, like tiny circuit elements, process and transmit information in a dramatic way that is intimately curious to researchers in the computer science and engineering fields. Of particular interest has been the recent push in applying microtechnology to the field of neuroscience. This review is meant to provide an overview of some of the subtle nuances of the nervous system and outline recent advances in lab on a chip applications in neurobiology. It also aims to highlight some of the challenges the field faces in the hopes of encouraging new engineering researchers to collaborate with neurobiologists to help advance our basic understanding of the nervous system and create novel applications based on neuroengineering principles.     

Synthesis and study of differentially substituted dibenzotetraazafulvalenes

A series of functionalized dibenzotetraazafulvalenes have been synthesized and characterized using X-ray crystallography, UV-vis spectroscopy, and cyclic voltammetry. The solid-state structures, electronic properties, and redox potentials of these compounds varied in accordance with the nature of the pendant arene substituent.     

An Index for 4 Dimensional Super Conformal Theories

We present a trace formula for an index over the spectrum of four dimensional superconformal field theories on S ³ × time. Our index receives contributions from states invariant under at least one supercharge and captures all information – that may be obtained purely from group theory – about protected short representations in 4 dimensional superconformal field theories. In the case of the theory our index is a function of four continuous variables. We compute it at weak coupling using gauge theory and at strong coupling by summing over the spectrum of free massless particles in AdS ₅ × S ⁵ and find perfect agreement at large N and small charges. Our index does not reproduce the entropy of supersymmetric black holes in AdS ₅, but this is not a contradiction, as it differs qualitatively from the partition function over supersymmetric states of the theory. We note that entropy for some small supersymmetric AdS ₅ black holes may be reproduced via a D-brane counting involving giant gravitons. For big black holes we find a qualitative (but not exact) agreement with the naive counting of BPS states in the free Yang Mills theory. In this paper we also evaluate and study the partition function over the chiral ring in the Yang Mills theory.     

Chain conformations and bound-layer correlations in polymer nanocomposites

Small angle neutron scattering studies on polystyrene loaded with spherical silica nanoparticles under contrast-matched conditions unequivocally show that chain conformations follow unperturbed Gaussian statistics independent of chain molecular weight and filler composition. Liquid state theory calculations are consistent with this conclusion and also predict filler-induced modification of interchain polymer correlations which have a distinctive scattering signature that is in nearly quantitative agreement with our observations.     

Charge distribution in heavy-ion reactions

Marked oscillations are seen in the differential cross section of charge distributions in high-energy heavy-ion reactions with massive projectiles. It is suggested that this can be explained by a simple quantum mechanical potential model over an “enlarged” Hilbert space.     

Conformation et spectrométrie de R.M.N.: II

The four isomeric 3-dimethylamino-trans-2-decalols-1,1,4,4-d₄ have been synthesised. Examination of PMR spectra of these compounds allows us to confirm the ‘flattened-chair’ conformation for the cis N(CH₃)₂^a OH^e isomer, whereas the remaining three conserve the double chair conformation. The same type of flattening is also observed in the case of the diaxial quaternary ammonium salt and is even more marked in the cis N(CH₃)₃^a OH^e isomer resulting in a ‘twist-chair’ conformation.