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Objective: Seasonal influenza is a preventable disease that may cause high morbidity and mortality. In the USA, the 2020 influenza season overlapped with the first wave of coronavirus disease 2019 (COVID-19) pandemic. There is a dearth of research on understanding influenza vaccination uptake and attitudes towards the vaccine among marginalised communities in the USA. The aim of this study was to examine general knowledge, misconceptions about, and barriers to influenza vaccination and determine if flu education delivered via trusted messengers improved knowledge among Asian Americans. Design: Quantitative prospective pre- and post-test design. Setting: Asian American communities in Metro Detroit area, Hamtramck, and Kent County in Michigan. Method: The study started with a training event in which 26 community leaders were trained to become trusted messengers to disseminate flu education. A total of 260 Asian American participants subsequently completed pre- and post-education surveys. Results: Asian Americans in the study reported low flu vaccination rate (48.5%). Reasons varied but included access-related issues (e.g. no access and no insurance) and health literacy (did not know they needed it). After education by trusted messengers, the paired t tests measuring improvement between pre- and post-survey scores showed a significant improvement ( p < .05) for all of the knowledge items. Conclusion: Educational campaigns using targeted messages to address specific barriers and acknowledge individuals’ concerns regarding misconceptions while providing equitable vaccine access can be key for the successful implementation of vaccination programmes.

We thank Gray and Back for their article on communication and covid-19.1 Conversations in our trust have increased and been complicated by the use of personal protective equipment. This particularly affects professionals and patients who are deaf2 but also affects those with other sensory impairments, dementia, or learning disabilities. Visiting has been restricted in UK hospitals,3 with a move towards telephone and video consultations.4 This is complex work, especially when phoning patients or families who …

Background and objective: Lead poisoning is a major public health crisis in Michigan. The purpose of this study was to explore the impact of an education intervention on knowledge and confidence levels among nursing students enrolled in the pre-licensure Bachelor of Science in Nursing and Registered Nurse to Bachelor of Science in Nursing (RN2BSN) program. Methods: The study used a quantitative pre- and post-test design to assess the impact of lead health learning activities on knowledge and confidence among undergraduate nursing students in the Midwestern United States. The final study sample included 115 nursing students from two student cohorts. The study instrument used 26-item Nursing Students Lead Knowledge and Confidence Scale; independent sample t -tests, paired sample t -test and Cohen’s d for the effect size were used in data analyses. Results: The education improved total knowledge and confidence on both groups whereas RN2BSN students had larger effect sizes on the differences of pre- to post-test scores than pre-licensure students in general lead knowledge, lead exposure knowledge, total lead knowledge, and confidence. Conclusions: The results contribute to limited literature examining a critical public health concern regarding lead health exposure and prevention education of nursing students. Incorporating such content area into nursing curriculums is essential in ensuring that such public health disparities are mitigated.

pH-responsive microgels are crosslinked polymer colloids that swell when the pH approaches the pK a of the particles. They have potential application for injectable gels for tissue repair and drug delivery systems. This study focuses on the pH-triggered gelation behaviour of a series of poly (EA/MAA/X) microgels. EA and MAA are ethylacrylate and methacrylic acid. Here, we investigate the effect of crosslinking monomer type (X) on microgel properties. The crosslinking monomers used were poly (ethyleneglycol) dimethacrylate (PEGD), ethyleneglycol dimethacrylate (EGD) and butanediol diacrylate (BDD). The microgel containing PEGD (m-PEGD) is a new system. The microgel containing BDD (m-BDD) was used as a control system. The concentrated microgel dispersions formed physical gels when the pH was increased to 5.3–6.7, and the polymer volume fractions (ϕ p ) were above about 0.05. Evidence from photon correlation spectroscopy (PCS) and dynamic rheology was presented for abrupt pH-triggered increases, and then decreases of the hydrodynamic diameters for m-PEGD and the microgel prepared using EGD (m-EGD). This appears to be tuneable through crosslinker structure. An unexpected gelation behaviour, which may involve a new gel state for microgels, was found for m-PEGD dispersions. Uniquely, those dispersions formed gels at pH values less than the microgel's pK a . This behaviour was linked to an outer-shell electrostatic repulsive interaction. The data point to a phenomenon, whereby the m-PEGD shells appear to explode at pH values above 7.0. The control microgel prepared, using BDD (m-BDD), did not show any evidence of shell fragmentation at any pH. That microgel has potential as a model pH-responsive microgel system in that the properties measured by PCS and rheology agreed well. To probe that system in more detail, the rheological data for m-BDD was analysed using scaling theory. The variation of the storage modulus (G') with ϕ p gave a scaling exponent of 2.0.

pH-responsive microgels are cross-linked polymer colloids that swell when the pH approaches the pK a of the particles. In this work, we present a comprehensive investigation of pH-triggered particle swelling and gel formation for a range of microgels containing methacrylic acid (MAA). The microgels investigated have the general composition poly(A/MAA/X), where A and X are the primary co-monomer and cross-linking monomer, respectively. The primary co-monomers were methyl methacrylate (MMA), ethyl acrylate (EA) or butyl methacrylate. The cross-linking monomers were either butanediol diacrylate (BDDA) or ethyleneglycol dimethacrylate (EGDMA). The microgels were studied using scanning electron microscopy, photon correlation spectroscopy (PCS) and dynamic rheology measurements. Gel phase diagrams were also constructed. The particles swelled significantly at pH values greater than approximately 6.0. It was shown that poly(EA/MAA/X) microgels swelled more strongly than poly(MMA/MAA/X) microgels. Furthermore, greater swelling occurred for particles prepared using EGDMA than BDDA. Concentrated dispersions of all the microgels studied exhibited pH-triggered gel formation. It was found that the fluid-to-gel transitions for the majority of the six microgel dispersions investigated could be explained using PCS data. In those cases, gelation was attributed to a colloidal glass transition. Interestingly, the microgels that were considered to have the highest hydrophobic content gelation occurred under conditions where little particle swelling was evident from PCS. The data presented show that gelled poly(EA/MAA/BDDA) and poly(MMA/MAA/EGDMA) microgel dispersions have the strongest elasticities at pH = 7.

Recently, our group established a new approach for preparing injectable hydrogels using vinyl-functionalised pH-responsive microgel particles [Liu et al., Soft Matter, 2011, 7, 4696]. pH-responsive microgels swell when the pH approaches the pKa of the particles. Liu et al. used inter-particle crosslinking of vinyl-functionalised microgel particles to prepare hydrogels composed of doubly crosslinked microgels (D-microgels). Here, we combine vinyl-functionalised microgels with added, small-molecule, crosslinkers to prepare high modulus D-microgel/hydrogel (H-X) composites for the first time. The vinyl-functionalised microgel particles used were poly(EA/MAA/BDD)/GM; where, EA MAA, BDD and GM are ethyl acrylate and methacrylic acid, 1,4-butanediol diacrylate and glycidyl methacrylate, respectively. Two added crosslinkers were used to demonstrate the versatility of our approach. They were ethyleneglycol dimethacrylate (EGD) and N,N′-methylenebisacrylamide (BA). We compare the data to control hydrogel composites prepared using non-vinyl-functionalised singly crosslinked microgels (S-microgels). All of the composites showed pH-dependent swelling behaviours and mechanical properties. The storage modulus value for the as-made D-microgel/H-EGD composite was 0.12 MPa and is the highest reported to date for a hydrogel containing pH-responsive microgels. The as-made control S-microgel/H-X composites had high ductilities. Dynamic rheology data were used to determine the effects of vinyl functionalisation on the composite mechanical properties. All of the composites exhibited pH-dependent swelling and a “breathing in” transition occurred. The swollen D-microgel/H-X composites retained their high modulus values upon swelling; although, their ductilities decreased. Because we used two different crosslinkers and pH-responsive microgels containing carboxylic acid groups, the method introduced here for preparing high modulus hydrogel composites should be widely applicable.

pH-Responsive microgels are crosslinked polymer particles that swell when the pH approaches the pKa of the polyacid or polybase chains. In this study we investigate for the first time pH-triggered physical gel (soft particle glass) formation from concentrated mixed dispersions of heteroaggregated pH-responsive microgels. The two microgels studied are poly(ethyl acrylate/methacrylic acid/1, 4-butanediol diacrylate) (referred to as PEAMAA) and poly(2-vinylpyridine/divinylbenzene) (referred to as PVP). The anionic PEAMAA particles are alkali-swellable and the cationic PVP particles are acid-swellable. Concentrated homodispersions formed physical gels at either low pH (PVP) or high pH (PEAMAA). The hard sphere (latex) particle size ratio (R = dPEAMAA/dPVP) was 0.15. Uniquely, the PEAMAA/PVP microgel heterodispersion allowed R to be varied by an order of magnitude (from 0.04 to 0.61) at a fixed particle number ratio simply by adjusting the solution pH. Concentrated PEAMAA/PVP heterodispersions formed physical gels at both low and high pH. Dynamic rheology measurements showed that at low pH the presence of collapsed PEAMAA particles greatly increased the storage modulus (G′) and also the critical yield strain (γc) of the mixed PEAMAA/PVP gels compared to the parent PVP homoparticle gel. A remarkably high G′ value of 0.12 MPa was obtained for a mixed PEAMAA/PVP gel containing 90 vol.% water. Our new, versatile method for preparing pH-responsive dispersions that form physical gels at two different pH values could lead to dual-action injectable gels for soft tissue repair.

The ability to tune the mechanical properties of hydrogel composites through the rational design of their constituents has excellent potential for providing advanced hydrogels for regenerative medicine applications. In this study we investigate the morphology and mechanical properties of a new family of pH-responsive hydrogel composites. They were prepared by adding crosslinking monomers (X) to concentrated dispersions of pH-responsive poly(EA/MAA/BDD) (ethylacrylate, methacrylic acid and butanediol diacrylate) MG particles. These MG/X dispersions formed physical gels. The dispersions were then polymerised to give pH-responsive hydrogel composites containing MGs, which are termed here as MG/H-X. The MG particles swelled strongly when the pH exceeded 6.0. The added crosslinking monomers were either ethyleneglycol dimethacrylate (EGD) or poly(ethylene glycol) dimethacrylate (PEGD). The latter had molecular weights in the range of 330 to 750 g/mol. If X had a molecular weight of 330 g/mol, or more, osmotic deswelling of the MG particles occurred. This strongly affected both the gelation behaviour of the MG/X dispersions and the mechanical properties of the chemically crosslinked MG/H-X hydrogel composites. For these new hydrogel composites X acted in two ways; it directed the morphology through osmotic deswelling of the MG particles and also provided a source of crosslinking. The storage modulus of the hydrogel composites was tuneable over a range of five orders of magnitude. The MG/H-X hydrogel composites showed pH-dependent swelling and mechanical properties. The hydrogel composites could also be prepared using poly(EA/MAA/EGD) and poly(EA/MAA/PEGD550) microgels. The simple method introduced here should enable construction of a wide range of pH-responsive hydrogel composites containing microgels with morphologies that can be tuned at the length scale of the MG particles, i.e., about 100 to 500 nm.