Three-dimensional (3D) cell culture systems are becoming increasingly popular due to their ability to mimic the complex process of angiogenesis in cancer, providing more accurate and physiologically relevant data than traditional two-dimensional (2D) cell culture systems. Microwell systems are particularly useful in this context as they provide a microenvironment that more closely resembles the in vivo environment than traditional microwells. Poly(ethylene glycol) (PEG) microwells are particularly advantageous due to their bio-inertness and the ability to tailor their material characteristics depending on the PEG molecular weight.
View Article and Find Full Text PDFThis work demonstrates the impact of intramolecular hydrogen bonding (H-bonding) on the calculated p of octahedral tris-(pyridinethiolato)nickel(II), [Ni(PyS)3]-, proton reduction catalysts. Density Functional Theory (DFT) calculations on a [Ni(PyS)3]- catalyst, and eleven derivatives, demonstrate geometric isomer formation in the protonation step of the catalytic cycle. Through Quantum Theory of Atoms in Molecules (QTAIM), we show that the p of each isomer is driven by intramolecular H-bonding of the proton on the pyridyl nitrogen to a sulfur on a neighboring ligand.
View Article and Find Full Text PDFPlanctomycetes are distinguished from other Bacteria by compartmentalization of cells via internal membranes, interpretation of which has been subject to recent debate regarding potential relations to Gram-negative cell structure. In our interpretation of the available data, the planctomycete Gemmata obscuriglobus contains a nuclear body compartment, and thus possesses a type of cell organization with parallels to the eukaryote nucleus. Here we show that pore-like structures occur in internal membranes of G.
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