When does legislation trigger regulation? The US Congress regularly passes laws that authorise government agencies to write legally binding regulations. Yet, when this occurs, agencies may take years to act – or, at times – may never act at all. We theorise that the breadth of the congressional statutory delegation drives the timing of agency policy production. In particular, when Congress expressly tells an agency to promulgate a rule, we expect agencies to do so quickly. Yet, when Congress provides greater policymaking discretion to agencies, we expect other factors – and especially, internal agency considerations – to drive regulatory timing. We use data from almost 350 statutes spanning four decades, which are then matched up with thousands of regulations, to assess the argument. Using innovative methods, we find support for our hypotheses. Overall, we produce a deeper understanding of the link between delegation and discretion: suggesting when it occurs, as well as, importantly, why.

The first demonstration of laser action in ruby was made in 1960 by T. H. Maiman of Hughes Research Laboratories, USA. Many laboratories worldwide began the search for lasers using different materials, operating at different wavelengths. In the UK, academia, industry and the central laboratories took up the challenge from the earliest days to develop these systems for a broad range of applications. This historical review looks at the contribution the UK has made to the advancement of the technology, the development of systems and components and their exploitation over the last 60 years.

Providing magnetite nanoparticles with saccharide coatings has been found to significantly increase the interactions of the nanoparticles with cells. Glucose (Glc) or N-acetylglucosamine (GlcNAc) coated magnetic nanoparticles (MNPs) were used to magnetically label 3T3 fibroblast cells, and the response of the labelled cells to external magnetic fields was studied. It was found that cells incubated with Glc- or GlcNAc-coated nanoparticles were much more likely to move towards an external magnet than those incubated with uncoated nanoparticles. Furthermore, cells in suspension moved much faster than those in contact with the surface of polystyrene well plates, with stronger magnets increasing the speed of movement. Cells that were adhering to the floor of the cell culture well and did not move in the x-y plane could still be rotated about the z-axis by moving the external magnet around the cell.

All administrative processes contain points of entry for politics, and the U.S. president's use of the Office of Management and Budget (OMB) to review government regulations is no exception. Specifically, OMB review can open up a pathway for interest groups to lobby for policy change. We theorize that interest group lobbying can be influential during OMB review, especially when there is consensus across groups. We use a selection model to test our argument with more than 1,500 regulations written by federal agencies that were subjected to OMB review. We find that lobbying is associated with change during OMB review. We also demonstrate that, when only business groups lobby, we are more likely to see rule change; however, the same is not true for public interest groups. We supplement these results with illustrative examples suggesting that interest groups can, at times, use OMB review to influence the content of legally binding government regulations.

The condensation of hydrazides with aldehydes has been found to be a simple and rapid method for synthesizing catechol-terminated coating reagents for magnetite nanoparticles. This approach allowed the production of biotin- and polyethylene glycol-functionalized nanoparticles, whose interaction with 3T3 fibroblast cells has been assessed. The cellular location of these nanoparticles was imaged by fluorescence microscopy, which was made possible by co-coating with a porphyrin-catechol conjugate. Images show significant interactions between biotinylated nanoparticles and 3T3 fibroblasts, but those with a polyethylene glycol coating did not interact.

Magnetic nanoparticle-vesicle aggregates (MNPVs), a controlled release nanostructure, have been enhanced with the inclusion of a novel galactose terminated lipid for cell targeting. Quartz crystal microgravimetry with dissipation (QCM-D) demonstrated that the galactose headgroup was available to bind Erythrina Crista-galli lectin (ECL) when the lipid was incorporated into a lipid bilayer. Similarly, UV-visible spectrophotometry indicated that ECL recognized the galactose headgroup in vesicles, leading to vesicle adhesion and aggregation. Finally, confocal fluorescence microscopy was used to assess the galactose-mediated interaction of both vesicles and MNPVs with HepG2 human hepatocellular carcinoma cells expressing the asialoglycoprotein (ASGPR) galactose receptor.

Several different hydrogel compositions have been incorporated into magnetic vesicle gels and the resulting “smart” biomaterials assessed as cell culture scaffolds. The compatibility of these hydrogels with the “smart” component of these biomaterials, thermally sensitive vesicles (TSVs) crosslinked by magnetic nanoparticles, was assessed by the leakage of fluorescent 5/6-carboxyfluorescein from the TSVs under cell culture conditions. Subsequently the ability of the hydrogels to support 3T3 fibroblast and chondrocyte viability was assessed. These studies revealed that alginate-based gels were the most compatible with both the TSVs and the cultured cells, with an alginate:fibronectin mix proving to be the most versatile. Nonetheless these studies also suggest that TSV composition needs to be modified to improve the performance of these “smart” cell culture scaffolds in future applications.

Drop-on-demand inkjet printing is a fabrication technique that is capable of depositing materials layer-by-layer to form complex 3-dimensional (3-D) constructs. Here we present a new single drop delivery method in which both the matrix and cross-linker are present but separated through the use of vesicle packaging. Changing the printing parameters has little effect on the integrity of the calcium(II)-loaded vesicles, with calcium(II) released selectively by warming after printing. Alginate solutions containing calcium(II)-loaded vesicles were successfully printed and the printed layers were shown to gel on demand at 37 °C. The printed alginate layers were evaluated with regards to their potential to provide 3-D structures for cell culture.