Front Cover: In article number 2000265 by Paul D. Dalton, Hans-Werner Schmidt, and co-workers, (AB)n copolymers composed of hydrophilic poly(ethylene glycol)-based segments bisurea segments, acting as physical crosslinks, are tailored for different melt-processing technologies. Defi ned 3D constructs can be made from extrusion-based printing melt electrowriting while a typical nonwoven morpholo...

We deduce a microstructure inspired model for humidity and temperature effects on the mechanical response of spider silks, modeled as composite material with hard crystalline soft amorphous region. Water molecules decrease percentage crosslinks in softer region inducing variation natural length macromolecules. The resulting kinematic incompatibility between regions crucially influences final re...

Green Polyvinyl Alcohol Interfacial crosslinking of green polyvinyl alcohol (PVA) and polycaprolactone (PCL) bilayer dielectric provides a barrier to moisture improves single walled carbon nanotube-based device performance. Benoit Lessard co-workers report functionalized PCL which crosslinks with the hydroxy groups PVA layer through simple heat treatment, providing candidate material for high p...

The development of a sliding hydrogel with mobile crosslinks and biochemical ligands as a 3D stem cell niche is reported. The molecular mobility of this sliding hydrogel allows stem cells to reorganize the surrounding ligands and change their morphology in 3D. Without changing matrix stiffness, sliding hydrogels support efficient stem cell differentiation toward multiple lineages including adip...

Left unrepaired, DNA interstrand crosslinks represent impassable hurdles for DNA replication, and their removal is a complicated stepwise process involving a variety of enzymes. In a recent paper in Science, Knipscheer et al. (2009) demonstrate that the Fanconi Anemia protein FANCD2 promotes multiple steps of the crosslink repair process.

Some compounds of hexavalent chromium are well-established carcinogens. Chromium enters mammalian cells in the hexavalent form and is reduced to chromium (III). Treatment of purified DNA with chromium (III) produces DNA-DNA interstrand crosslinks (DDC) which obstruct the progression of DNA polymerases in vitro. DDC were also detected in chromate-treated cultured normal human lung cells using th...