Targeted Temperature Management After Pediatric Cardiac Arrest: A Quality Improvement Program With Multidisciplinary Implementation in the PICU.

Objectives: We aimed to implement a post-cardiac arrest targeted temperature management (TTM) bundle to reduce the percent of time with a fever from 7% to 3.5%.

Design: A prospective, quality improvement (QI) initiative utilizing the Method for Improvement.

Diblock bottlebrush polymer in a non-polar medium: Self-assembly, surface forces, and superlubricity.

Whilst bottlebrush polymers have been studied in aqueous media for their conjectured role in biolubrication, surface forces and friction mediated by bottlebrush polymers in non-polar media have not been previously reported. Here, small-angle neutron scattering (SANS) showed that a diblock bottlebrush copolymer (oligoethyleneglycol acrylate/ethylhexyl acrylate; OEGA/EHA) formed spherical core-shell aggregates in n-dodecane (a model oil) in the polymer concentration range 0.1-2.

Surface forces and friction between Langmuir-Blodgett polymer layers in a nonpolar solvent.

Optimization of boundary lubrication by tuning the confined molecular structures formed by surface-active additives such as surfactants and polymers is of key importance to improving energy efficiency in mechanical processes. Here, using the surface forces apparatus (SFA), we have directly measured the normal and shear forces between surface layers of a functionalised olefin copolymer (FOCP) in n-dodecane, deposited onto mica using the Langmuir-Blodgett (LB) technique. The FOCP has an olefin backbone decorated with a statistical distribution of polar-aromatic groups, with a structure that we term as "centipede".

Racial/Ethnic Discrimination and Food Consumption: Examination in Diverse Samples.

Background: Racial/ethnic discrimination has been linked to poor health outcomes. Effects of discrimination on health behaviors, including patterns of food consumption, may contribute to health outcomes.

Purpose: We examined relations of discrimination to consumption of healthy and unhealthy foods in two diverse samples.

The discovery of the depletion force.

This Editorial reports how the depletion force theory was originally developed by Sho Asakura and Fumio Oosawa and how their one-page paper was "rediscovered" about 20 years after the paper was published. The first part of this Editorial is mostly based on the lecture by Oosawa and his autobiographies, and the second part is written by one of two scientists who found the paper. The aim of this Editorial is to record the background of the discovery of the depletion force.

McBain and the centenary of the micelle.

In 1913, J.W. McBain introduced the word "micelle" into surface and colloid chemistry in the context of the association of surfactant molecules in aqueous solution.

Early (pre-DLVO) studies of particle aggregation.

The history of colloid science, from its modern foundations in the mid-nineteenth century, has been strongly concerned with studies of the aggregation of colloidal particles. It was Thomas Graham (1861) who defined the word "colloid" (from the Greek word for glue) for those materials which could not pass through membranes, unlike smaller, truly-dissolved materials. Subsequently, Graham (1864), following earlier studies, principally by Selmi and Faraday, described "the power possessed by salts for destroying colloidal solutions".

Photo-responsive properties of poly(NIPAM-co-AAc) microgel particles with absorbed, hydrophobically modified organic salts.

The absorption of two hydrophobically modified organic salts (HMOSs), containing azobenzene units, into poly(N-isopropylacrylamide-co-acrylic acid) microgel particles has been studied at pH 8 and 20 °C. These dispersions were then irradiated with UV light (wavelength 365 nm) for 10 min to observe the effect on the microgel particle properties, such as the adsorbed amount of the HMOS, the particle size, and the electrophoretic mobility. We show that irradiation of these dispersions with UV light can lead to induced, partial desorption of the HMOS molecules, with concomitant changes in the size and electrophoretic mobility of the microgel particles.

Electrically induced colloidal clusters for generating shear mixing and visualizing flow in microchannels.

When aqueous suspensions of 1 μm, negatively charged polystyrene particles are subject to a 1 kHz alternating electric field of strength greater than 7 kV(rms) m(-1), dynamic elliptical clusters of particles spontaneously form. With potential applications in microchannel fluidics in mind, we characterize how cluster formation and particle circulation, driven by induced dipole-dipole interactions, is critically dependent on time, field strength, electrolyte concentration, and cell thickness. Logarithmic growth of cluster size is observed, and particle velocity within the clusters is found to be proportional to cluster length.

Effect of chain length on the interaction between modified organic salts containing hydrocarbon chains and poly(N-isopropylacrylamide-co-acrylic acid) microgel particles.

A series of four hydrophobically modified, diphenylazo-based organic salts have been prepared and characterized. To achieve this a C(x) (x = 4, 6, 8, or 10) hydrocarbon chain was inserted between the diphenylazo moiety and the quaternary ammonium headgroup of the salt. The absorption of each of the four modified organic salts into anionic microgel particles of poly(N-isopropylacrylamide-co-acrylic acid) has been studied at pH 8.

Two-stage phase separation in ternary colloid-polymer mixtures.

Whilst binary colloid-polymer mixtures have been studied in detail over the past few decades, here the first results are presented on a ternary mixture involving two particle sizes. Novel and unusual phase separation kinetics are found, with a liquid phase separating from an aggregate phase.

MiS-MALDI: microgel-selected detection of protein biomarkers by MALDI-ToF mass spectrometry.

Intensified efforts to decipher the origin of disease at the molecular level stimulate the emergence of more efficient proteomic technologies. To complement this, attempts are being made to identify new predictive biomarkers for building more reliable biomarker patterns. As biomarker research gathers pace an immediate interest becomes focused on platforms, which although based on mainstream approaches, are more amenable to specialist tasks.

Interaction between lysozyme and colloidal poly(NIPAM-co-acrylic acid) microgels.

The interaction between lysozyme and colloidal poly(NIPAM-co-acrylic acid) microgels is investigated in aqueous solutions at neutral pH. Lysozyme binding isotherms, obtained within the ionic strength range 10-220 mM, indicate that the maximum uptake at 10 mM is 2.4 g lysozyme per gram dry gel, and that the uptake capacity decreases with increasing ionic strength to approximately 0 at 220 mM.

The phase behavior of dispersions of silica particles in mixtures of polystyrene and dimethylformamide.

Depletion-induced phase separation in mixtures of charged silica particles and nonadsorbing polymer near theta conditions (polystyrene in dimethylformamide) was studied. The colloid-polymer size ratio q was varied through the particle size and the electrical double layer thickness (kappa(-1)) through addition of lithium chloride (LiCl). The dependence of the phase boundaries, and the nature of the separated phases, on q and kappa is reported and is found to be in good agreement with recent theoretical predictions (Gogelein, C.

Organic-inorganic double shell composite microcapsules.

Here we present novel double shell composite microcapsules (melamine formaldehyde (MF) polymer inner shell and ripened CaCO(3) nanoparticle outer shell) prepared using a method based on in situ polymerisation to form a MF polymer shell inside the ripened CaCO(3) nanoparticulate microcapsules wall.

The interaction between multi-charged organic salts and poly(vinylpyridine) microgel particles.

The interaction between negatively charged organic salts, with one two and three sulfonate groups respectively, and positively charged poly(2-vinylpyridine) microgel particles has been investigated. Absorption isotherms are used to describe the uptake of organic salt into the microgel network and the particle size and electrophoretic mobility of the dispersions have been discussed in terms of the electrostatic attraction between the organic salts and microgel network. The results suggest that all organic salts interact weakly with the microgel particles, and there is a tendency towards more noticeable changes in the microgel dispersion properties at lower concentration as the number of sulfonate groups within the organic salts increases.

Aqueous dispersions of silica shell/water-core microcapsules.

The preparation is described of water-core/silica-based shell particles, from W/O emulsion droplets, by adding alkoxysilanes to the oil-continuous phase, to form the shell by an interfacial condensation reaction at the W/O interface. In order to form relatively thick (and hence stronger) shells, it is found necessary to use a mixture of tetraethoxysilane (TEOS) and diethoxydimethylsilane (DEODMS), rather than TEOS alone. It is suggested that, in the former case, trans-shell diffusion of the alkoxysilane monomers (from the oil side) and water molecules (from the aqueous side) can continue, as a result of the higher permeability of the shells to these small molecules, thus allowing the interfacial condensation reaction to continue, even when the reaction would have ceased for a harder shell, having a much lower permeability, as occurs when TEOS alone is used.

The uptake and release of cationic surfactant from polyampholyte microgel particles in dispersion and as an adsorbed monolayer.

The use of novel polyampholyte microgel particles for the controlled absorption and release of a cationic surfactant has been investigated. The addition of cetylpyridinium chloride (CPC) to aqueous dispersions of poly(2-diethylamino)ethyl methacrylate-co-methacrylic acid (DEAEM-co-MAAc) microgel particles has been studied with respect to CPC concentration and solution pH. CPC was found to absorb into the polyampholyte microgel particles, resulting in reduced hydrodynamic diameter and electrophoretic mobility, when added to microgel dispersion at pH 11.

Silica-shell/oil-core microcapsules with controlled shell thickness and their breakage stress.

The encapsulation of one material by another, to form core-shell particles (microcapsules), has many applications, principally the containment, protection, and distribution of an active material. This work describes the development of core-shell particles with silicone oil cores and solid silica-like shells of controlled thickness. Oligomeric polydimethylsiloxane (PDMS) emulsions are employed as the core templates for the formation of the solid shells.

Simple models for two-dimensional tunable colloidal crystals in rotating ac electric fields.

We compare the behavior of a new two-dimensional aqueous colloidal model system with a simple numerical treatment. To the first order the attractive interaction between the colloids induced by an in-plane rotating ac electric field is dipolar, while the charge stabilization leads to a shorter ranged, Yukawa-like repulsion. In the crystal-like "rafts" formed at sufficient field strengths, we find quantitative agreement between experiment and Monte Carlo simulation, except in the case of strongly interacting systems, where the well depth of the effective potential exceeds 250 times the thermal energy.

Synthesis of amphoteric polystyrene particles using mixed initiators.

The synthesis of amphoteric polystyrene latex particles, using a mixture of cationic (amidinium based) and anionic (carboxylic acid based) initiators in a surfactant-free emulsion polymerization reaction is investigated; this extends work described in an earlier paper by Bolt et al. Electrophoretic mobility measurements show the effect of the initiator concentration ratio on the isoelectric point (IEP) of the particles. A good correlation with theoretical predictions is obtained.

Poly(vinylpyridine) core/poly(N-isopropylacrylamide) shell microgel particles: their characterization and the uptake and release of an anionic surfactant.

The use of microgel particles for controlled uptake and release of active species has great potential. The compatibility of microgel particles with their environment and the functionality of the particles can be achieved by modification of the core microgel through the addition of a shell. In this work, core-shell microgel particles, with a pH-responsive core (polyvinylpyridine) and a temperature-responsive shell (poly-N-isopropylacrylamide), have been prepared and characterized.