Conformation of a Polyelectrolyte Complexed to a Like-Charged Colloid

We report results from a molecular dynamics (MD) simulation on the conformations of a long flexible polyelectrolyte complexed to a charged sphere, \textit{both negatively charged}, in the presence of neutralizing counterions in the strong Coulomb coupling regime. The structure of this complex is very sensitive to the charge density of the polyelectrolyte. For a fully charged polyelectrolyte the polymer forms a dense two-dimensional "disk", whereas for a partially charged polyelectrolyte the monomers are spread over the colloidal surface. A mechanism involving the \textit{overcharging} of the polyelectrolyte by counterions is proposed to explain the observed conformations.Comment: 4 pages, 4 figures (6 EPS files

Engaging patients, clinicians and health funders in weight management: the Counterweight Programme.

Background. The Counterweight Programme provides an evidence based and effective approach for weight management in routine primary care. Uptake of the programme has been variable for practices and patients. Aim. To explore key barriers and facilitators of practice and patient engagement in the Counterweight Programme and to describe key strategies used to address barriers in the wider implementation of this weight management programme in UK primary care. Methods. All seven weight management advisers participated in a focus group. In-depth interviews were conducted with purposeful samples of GPs (n = 7) and practice nurses (n = 15) from 11 practices out of the 65 participating in the programme. A total of 37 patients participated through a mixture of in-depth interviews (n = 18) and three focus groups. Interviews and focus groups were analysed for key themes that emerged. Results. Engagement of practice staff was influenced by clinicians beliefs and attitudes, factors relating to the way the programme was initiated and implemented, the programme content and organizational/contextual factors. Patient engagement was influenced by practice endorsement of the programme, clear understanding of programme goals, structured proactive follow-up and perception of positive outcomes. Conclusions. Having a clear understanding of programme goals and expectations, enhancing self-efficacy in weight management and providing proactive follow-up is important for engaging both practices and patients. The widespread integration of weight management programmes into routine primary care is likely to require supportive public policy

Isometric handgrip as an adjunct for blood pressure control: a primer for clinicians

Considered a global health crisis by the World Health Organization, hypertension (HTN) is the leading risk factor for death and disability. The majority of treated patients do not attain evidence-based clinical targets, which increases the risk of potentially fatal complications. HTN is the most common chronic condition seen in primary care; thus, implementing therapies that lower and maintain BP to within-target ranges is of tremendous public health importance. Isometric handgrip (IHG) training is a simple intervention endorsed by the American Heart Association as a potential adjuvant BP-lowering treatment. With larger reductions noted in HTN patients, IHG training may be especially beneficial for those who (a) have difficulties continuing or increasing drug-based treatment; (b) are unable to attain BP control despite optimal treatment; (c) have pre-HTN or low-risk stage I mild HTN; and (d) wish to avoid medications or have less pill burden. IHG training is not routinely prescribed in clinical practice. To shift this paradigm, we focus on (1) the challenges of current HTN management strategies; (2) the effect of IHG training; (3) IHG prescription; (4) characterizing the population for whom it works best; (5) clinical relevance; and (6) important next steps to foster broader implementation by clinical practitioners

Mixed Systems of Hydrophobically Modified Polyelectrolytes: Controlling Rheology by Charge and Hydrophobe Stoichiometry and Interaction Strength

Rheology and phase separation were investigated for aqueous mixtures of two oppositely charged hydrophobically modified polyelectrolytes. The typical phase separation, normally seen for oppositely charged polymer mixtures, is dramatically reduced by the presence of hydrophobic modification, and phase separation is only detected close to the point of charge neutralization. While the two polyelectrolytes separately can give high viscosities and a gel-like behavior, a pronounced maximum in viscosity and storage modulus with the mixing ratio of the polyelectrolytes is observed; the maximum is located between the points of charge and hydrophobe stoichiometry and reflects a combination of hydrophobic and electrostatic association. Lowering the charge density of the anionic polymer leads to a strengthened association at first, but at lower charge densities there is a weakened association due to the onset of phase separation. The strength of the electrostatic interaction was modified by adding salt. Increased ionic strength can lead to phase separation and to increased or decreased viscosity depending on the polyelectrolyte mixing ratio