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* OBJECTIVES: To (1) investigate whether different labels for neck pain after a motor vehicle crash (MVC) influenced recovery expectations and management beliefs, (2) explore reasons for low recovery expectations and greater likelihood for lodging a claim, and (3) explore the moderating effect of neck pain history and sociodemographic characteristics. * DESIGN: Online randomized experiment with nested qualitative content analysis. * METHODS: We randomized 2229 participants from the general population (mean age: 46.7 ± 17.5 years; 72.4% females; 66% with previous or current neck pain; 10% with an MVC experience) to read 1 of 5 scenarios describing a patient with neck pain after an MVC, each was labeled as whiplash injury, whiplash-associated disorder, posttraumatic neck pain, neck pain, or neck strain. The primary outcome was recovery expectations, rated on a 0- to 10-point scale. * RESULTS: Participants allocated to whiplashassociated disorder or neck pain had lower recovery expectations than those allocated to neck strain (adjusted mean difference [95% confidence interval]: -0.5 [-0.9 to -0.1] for both comparisons). Whiplash-associated disorder led to more recovery uncertainty, while neck pain led to greater doubt about the health care provider. Most secondary outcomes showed significant but small differences. Participants allocated to neck strain were less inclined to claim than those allocated to whiplash-associated disorder or whiplash injury due to less perceived need for financial support. Neck pain history moderated labeling effects on recovery expectations; household income moderated the claim intention. * CONCLUSIONS: Labels for neck pain after an MVC influenced recovery expectations and management preferences. The clinical relevance of the small effects was unclear. [ABSTRACT FROM AUTHOR]

Histamine functionalized block copolymers based on poly(allyl glycidyl ether)-b-poly(ethylene oxide) (PAGE-b-PEO) were prepared with different ratios of histamine and octyl or benzyl groups using UV-initiated thiol-ene click chemistry. At neutral pH, the histamine units are uncharged and hydrophobic, while in acidic environments, such as in the endosome, lysosomes, or extracellular sites of tumours, the histamine groups are positively charged and hydrophilic. pH responsible polymer drug delivery systems is a promising route to site specific delivery of drugs and offers the potential to avoid side effects of systemic treatment. Our detailed in vitro experiments of the efficacy of drug delivery and the intracellular localization characteristics of this library of NPs in 2D and 3D cultures of breast cancer revealed that the 50% histamine-modified polymer loaded with DOX exhibited rapid accumulation in the nucleus of free DOX within 2 h. Confocal studies showed enhanced mitochondrial localization and lysosomal escape when compared to controls. From these combined studies, it was shown that by accurately tuning the structure of the initial block copolymers, the resulting self-assembled NPs can be designed to exploit histamine as an endosomal escape trigger and the octyl/benzyl units give rise to a hydrophobic core resulting in highly efficacious drug delivery systems (DDS) with control over intracellular localization. Optimization and rational control of the intracellular localization of both DDS and the parent drug can give nanomedicines a substantial increase in efficacy and should be explored in future studies.

Bio‐based or partially bio‐based thermally expandable microspheres (TEMs) were synthesized by suspension (co)polymerization of the bio‐based monomer α‐methylene‐γ‐valerolactone (MeMBL) together with acrylonitrile and/or methyl methacrylate to form expandable core/shell particles by encapsulating a hydrocarbon‐based blowing agent. The core/shell polymers were characterized with respect to their chemical structure, thermal expansion, and morphology. The obtained particles, TEMs, showed an increasing onset expansion temperature with increasing content of MeMBL owing to the high glass transition temperature of PMeMBL. As a result, bio‐based/partially bio‐based TEMs are achieved with high thermal stability and expansion properties which can be tailored for various applications. [ABSTRACT FROM AUTHOR]

The colloidal layer formation on porous materials is a crucial step for printing and applying functional coatings, which can be used to fabricate anticounterfeiting paper. The deposition of colloidal layers and subsequent thermal treatment allows for modifying the hydrophilicity of the surface of a material. In the present work, wood-based colloidal inks are applied by spray deposition on spray-deposited porous cellulose nanofibrils (CNF) films. The surface modification by thermal annealing of the fabricated colloid-cellulose hybrid thin films is investigated in terms of layering and hydrophobicity. The polymer colloids in the inks are core–shell nanoparticles with different sizes and glass transition temperatures (Tg), thus enabling different and low thermal treatment temperatures. The ratio between the core polymers, poly-(sobrerol methacrylate) (PSobMA), and poly-(-butyl methacrylate) (PBMA) determines the Tg and hence allows for tailoring of the Tg. The layer formation of the colloidal inks on the porous CNF layer depends on the imbibition properties of the CNF layer which is determined by their morphology. The water adhesion of the CNF layer decreases due to the deposition of the colloids and thermal treatment except for the colloids with a size smaller than the void size of the porous CNF film. In this case, the colloids are imbibed into the CNF layer when Tg of the colloids is reached and the polymer chains transit in a mobile phase. Tailored aggregate and nanoscale-embedded hybrid structures are achieved depending on the colloid properties. The imbibition of these colloids into the porous CNF films is verified with grazing incidence small-angle X-ray scattering. This study shows a route for tuning the nanoscale structure and macroscopic physicochemical properties useful for anticounterfeiting paper. [ABSTRACT FROM AUTHOR]

Correlating nanostructure and optical properties of thin hybrid films is the crucial ingredient for designing sustainable applications ranging from structural colors in anticounterfeiting to sensors. Here, the tailoring of the refractive index of hybrid cellulose nanofibril/water‐dispersed colloidal ink thin films is presented. The authors apply scalable, layer‐by‐layer slot‐die coating for preparing the cellulose nanofibril and hybrid thin films. Making use of the mobility of the polymer chains in the colloids upon annealing, the influence of the different colloid sizes and their glass transition temperature on the refractive index of the hybrid material is shown. The complex refractive indices of the thin films are characterized by spectroscopic ellipsometry and correlated to the different nanostructures of the thin films. The authors find that post‐deposition annealing changes the colloidal nanostructure from particulate to agglomerates. Depending on the size of the colloids, imbibition of the colloids into the cellulose nanofibril template is observed. This scalable approach offers new avenues in structural color functional biomaterial hybrid layers. [ABSTRACT FROM AUTHOR]

To address the increasing demand for biobased materials, lignin-derived ferulic acid (FA) is a promising candidate. In this study, an FA-derived styrene-like monomer, referred to as 2-methoxy-4-vinylphenol (MVP), was used as the platform to prepare functional monomers for radical polymerizations. Hydrophobic biobased monomers derived from MVP were polymerized via solution and emulsion polymerization resulting in homo- and copolymers with a wide range of thermal properties, thus showcasing their potential in thermoplastic applications. Moreover, divinylbenzene (DVB)-like monomers were prepared from MVP by varying the aliphatic chain length between the MVP units. These biobased monomers were thermally crosslinked with thiol-bearing reagents to produce thermosets with different crosslinking densities in order to demonstrate their thermosetting applications. The results of this study expand the scope of MVP-derived monomers that can be used in free-radical polymerizations toward the preparation of new biobased and functional materials from lignin. [ABSTRACT FROM AUTHOR]

Cellulose nanofibril (CNF)‐networks are modified by the addition of small amounts (below 10 wt%) of well‐defined cationic nanolatexes synthesized through reversible addition–fragmentation chain‐transfer‐mediated polymerization‐induced self‐assembly (PISA). Minute amounts of nanolatex inclusions lead to increased tensile and shear moduli, indicating that nanolatexes can act as bridging‐points between CNFs. At higher nanolatex content, this stiffening effect is lost, likely due to interactions between nanolatexes leading to plasticization. The influence of nanolatex content and size on interparticle distance is discussed and is used as a tool to understand the effects observed in macroscopic properties. Upon annealing, the stiffening effect is lost due to the softening of the nanolatexes, indicating that the core–shell morphology is a prerequisite for this effect. These systems form a versatile platform to develop fundamental insights into complex condensed colloidal systems, to ultimately aid in the development of new sustainable material concepts. [ABSTRACT FROM AUTHOR]

Understanding and tuning nanoscale structure is critical in developing new coatings and adhesives. In this work layer‐by‐layer assembly of block co‐polymer (BCP) micelles and oppositely charged polyelectrolytes produces structurally unique coatings with wet adhesion comparable to that of mussel adhesive proteins. Cationic (CAT) and anionic (ANI) BCPs, synthesized by atom transfer radical polymerization (ATRP), are used to create colloidally stable, self‐assembled, spherical BCP micelles. The assembly of BCP micelle and polyelectrolyte multilayers is monitored in situ where CAT‐ and ANI‐BCP micelles exhibit linear and super‐linear growth, respectively. Imaging of the surfaces reveals that CAT‐BCP micelles yield flat, uniform layers whereas ANI‐BCP micelle assemblies form islands that increase in surface area with each additional layer. The adhesion of these layers, measured by colloidal probe atomic force microscopy (CP‐AFM), shows that the distinct layers of CAT‐BCP micelle assemblies produce alternating high and low adhesion surfaces whereas ANI‐BCP micelle assemblies continually increase in adhesion with each additional bilayer. The unique behavior of each assembly demonstrates that both composition and structure play important roles in wet adhesion of submicron layers and that each can be tuned to target performance for different applications. [ABSTRACT FROM AUTHOR]