Publications by authors named "Hawker C"

Smartphones can extend the reach of evidence-based gambling treatment services, yet the general acceptability of app-delivered gambling interventions remains unknown. This study examined the general acceptability and use of app-delivered gambling interventions, and predictors of both, among 173 Australian adults with a lifetime gambling problem (48.5% male, M = 46.

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Bioinspired hydroxypyridinone (HOPO)functionalized materials are shown to display a remarkable capacity for stability and for chelating a wide array of metal ions. This allows for the synthesis of multifunctional networks with diverse physical properties when compared to traditional catechol systems. In the present study, we report a facile, one-pot synthesis of an amino HOPO ligand and simple, scalable incorporation into PEG-acrylate based networks via active ester chemistry.

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Silicone bottlebrush copolymers and networks derived from cyclic carbosiloxanes are reported and shown to have enhanced properties and recyclability compared with traditional dimethylsiloxane-based materials. The preparation of these materials is enabled by the synthesis of well-defined heterotelechelic macromonomers with Si-H and norbornene chain ends via anionic ring-opening polymerization of the hybrid carbosiloxane monomer 2,2,5,5-tetramethyl-2,5-disila-1-oxacyclopentane. These novel heterotelechelic α-Si-H/ω-norbornene macromonomers undergo efficient ring-opening metathesis copolymerization to yield functional bottlebrush polymers with accurate control over molecular weight and functional-group density.

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Article Synopsis
  • * These polymer-based diazirine cross-linkers enhance compatibility and efficiency in blending due to their high functionalization and adjustable multivalency.
  • * An example demonstrated that unmodified poly(-butyl acrylate) can be effectively cross-linked using low levels of polymeric diazirine in just one minute under light, achieving high gel fractions and tunable properties.
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A robust method is described to synthesize degradable copolymers under aqueous miniemulsion conditions using α-lipoic acid as a cheap and scalable building block. Simple formulations of α-lipoic acid (up to 10 mol %), -butyl acrylate, a surfactant, and a costabilizer generate stable micelles in water with particle sizes <200 nm. The ready availability of these starting materials facilitated performing polymerization reactions at large scales (4 L), yielding 600 g of poly(-butyl acrylate--α-lipoic acid) latexes that degrade under reducing conditions (250 kg mol → 20 kg mol).

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The development of renewable vinyl-based photopolymer resins offers a promising solution to reducing the environmental impact associated with 3D printed materials. This study introduces a bifunctional lipoate cross-linker containing a dynamic disulfide bond, which is combined with acrylic monomers (-butyl acrylate) and conventional photoinitiators to develop photopolymer resins that are compatible with commercial stereolithography 3D printing. The incorporation of disulfide bonds within the polymer network's backbone imparts the 3D printed objects with self-healing capabilities and complete degradability.

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Solution formulations involving polymers are the basis for a wide range of products spanning consumer care, therapeutics, lubricants, adhesives, and coatings. These multicomponent systems typically show rich self-assembly and phase behavior that are sensitive to even small changes in chemistry and composition. Longstanding computational efforts have sought techniques for predictive modeling of formulation structure and thermodynamics without experimental guidance, but the challenges of addressing the long time scales and large length scales of self-assembly while maintaining chemical specificity have thwarted the emergence of general approaches.

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Objective: The objective of this review was to identify lung transplant recipients' experiences of and attitudes towards self-management.

Introduction: Lung transplantation is an established treatment to improve the survival of patients with end-stage lung diseases and has been performed on more than 40,000 patients worldwide. The current focus of care for lung transplant recipients is long-term management.

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Aim: To assess student nurses understanding and skills in the application of antimicrobial stewardship knowledge to practice.

Design: Quantitative.

Methods: Cross-sectional survey.

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Manual hand-hygiene audit is time-consuming, labour-intensive and inaccurate. Automated hand-hygiene monitoring systems (AHHMSs) offer advantages (generation of standardized data, avoidance of the Hawthorne effect). World Health Organization Guidelines for Hand Hygiene published in 2009 suggest that AHHMSs are a possible alternative.

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ConspectusThe preparation of discrete and well-defined polymers is an emerging strategy for emulating the remarkable precision achieved by macromolecular synthesis in nature. Although modern controlled polymerization techniques have unlocked access to a cornucopia of materials spanning a broad range of monomers, molecular weights, and architectures, the word "controlled" is not to be confused with "perfect". Indeed, even the highest-fidelity polymerization techniques─yielding molar mass dispersities in the vicinity of = 1.

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We report a unique method to construct hierarchical superstructures based on molecular programming of peptidomimetics. Chiral steric hindrance in the polymer backbone stabilizes peptoid helices that crystallize into nanosheets during solvent evaporation. The stacking of nanosheets results in flower-like superstructures.

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The development of synthetic oligomers as discrete single molecular entities with accurate control over the number and nature of functional groups along the backbone has enabled a variety of new research opportunities. From fundamental studies of self-assembly in materials science to understanding efficacy and safety profiles in biology and pharmaceuticals, future directions are significantly impacted by the availability of discrete, multifunctional oligomers. However, the preparation of diverse libraries of discrete and stereospecific oligomers remains a significant challenge.

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Dynamic nuclear polarization (DNP) can amplify the solid-state nuclear magnetic resonance (NMR) signal by several orders of magnitude. The mechanism of DNP utilizing α,γ-bisdiphenylene-β-phenylallyl (BDPA) variants as Polarizing Agents (PA) has been the subject of lively discussions on account of their remarkable DNP efficiency with low demand for microwave power. We propose that electron spin clustering of sulfonated BDPA is responsible for its DNP performance, as revealed by the temperature-dependent shape of the central DNP profile and strong electron-electron (e-e) crosstalk seen by Electron Double Resonance.

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The synthetic utility of heterotelechelic polydimethylsiloxane (PDMS) derivatives is limited due to challenges in preparing materials with high chain-end fidelity. In this study, anionic ring-opening polymerization (AROP) of hexamethylcyclotrisiloxane (D) monomers using a specifically designed silyl hydride (Si-H)-based initiator provides a versatile approach toward a library of heterotelechelic PDMS polymers. A novel initiator, where the Si-H terminal group is connected to a C atom (H-Si-C) and not an O atom (H-Si-O) as in traditional systems, suppresses intermolecular transfer of the Si-H group, leading to heterotelechelic PDMS derivatives with a high degree of control over chain ends.

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The promise of ABC triblock terpolymers for improving the mechanical properties of thermoplastic elastomers is demonstrated by comparison with symmetric ABA/CBC analogs having similar molecular weights and volume fraction of B and A/C domains. The ABC architecture enhances elasticity (up to 98% recovery over 10 cycles) in part through essentially full chain bridging between discrete hard domains leading to the minimization of mechanically unproductive loops. In addition, the unique phase space of ABC triblocks also enables the fraction of hard-block domains to be higher ( ≈ 0.

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Here, we present the synthesis and characterization of statistical and block copolymers containing α-lipoic acid (LA) using reversible addition-fragmentation chain-transfer (RAFT) polymerization. LA, a readily available nutritional supplement, undergoes efficient radical ring-opening copolymerization with vinyl monomers in a controlled manner with predictable molecular weights and low molar-mass dispersities. Because lipoic acid diads present in the resulting copolymers include disulfide bonds, these materials efficiently and rapidly degrade when exposed to mild reducing agents such as tris(2-carboxyethyl)phosphine ( = 56 → 3.

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Biomolecular assembly processes involving competition between specific intermolecular interactions and thermodynamic phase instability have been implicated in a number of pathological states and technological applications of biomaterials. As a model for such processes, aqueous mixtures of oppositely charged homochiral polypeptides such as poly-l-lysine and poly-l-glutamic acid have been reported to form either β-sheet-rich solid-like precipitates or liquid-like coacervate droplets depending on competing hydrogen bonding interactions. Herein, we report studies of polypeptide mixtures that reveal unexpectedly diverse morphologies ranging from partially coalescing and aggregated droplets to bulk precipitates, as well as a previously unreported re-entrant liquid-liquid phase separation at high polypeptide concentration and ionic strength.

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Background: Health professionals frequently conduct procedures requiring asepsis but there is no definitive evidence-based guidance on how aseptic technique should be undertaken.

Objective: To undertake content and cluster analysis to compare and contrast information relating to the conduct of aseptic technique in national and international guidance.

Methods: Content and hierarchical cluster analysis.

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Shear-recoverable hydrogels based on block copolypeptides with rapid self-recovery hold potential in extrudable and injectable 3D-printing applications. In this work, a series of 3-arm star-shaped block copolypeptides composed of an inner hydrophilic poly(l-glutamate) domain and an outer β-sheet forming domain is synthesized with varying side chains and block lengths. By changing the β-sheet forming domains, hydrogels with diverse microstructures and mechanical properties are prepared and structure-function relationships are determined using scattering and rheological techniques.

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Pressure-sensitive adhesives (PSAs) based on poly(acrylate) chemistry are common in a wide variety of applications, but the absence of backbone degradability causes issues with recycling and sustainability. Here, we report a strategy to create degradable poly(acrylate) PSAs using simple, scalable, and functional 1,2-dithiolanes as drop-in replacements for traditional acrylate comonomers. Our key building block is α-lipoic acid, a natural, biocompatible, and commercially available antioxidant found in various consumer supplements.

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Bioinspired iron-catechol cross-links have shown remarkable success in increasing the mechanical properties of polymer networks, in part due to clustering of Fe-catechol domains which act as secondary network reinforcing sites. We report a versatile synthetic procedure to prepare modular PEG-acrylate networks with independently tunable covalent bis(acrylate) and supramolecular Fe-catechol cross-linking. Initial control of network structure is achieved through radical polymerization and cross-linking, followed by postpolymerization incorporation of catechol units via quantitative active ester chemistry and subsequent complexation with iron salts.

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Background: Aseptic technique is essential to prevent healthcare-associated infection and reduce the risk of antimicrobial resistance but little research has explored how it is taught in undergraduate nursing curricula.

Objective: Explore how undergraduate student nurses learn about aseptic technique in classroom and clinical settings and the contribution of key stakeholders in the educational process: nurse educators, mentors and infection prevention nurses.

Design: Qualitative interview study with observation of teaching.

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Background: Invasive devices and breaches to skin and mucous membranes increase susceptibility to infection. Nurses frequently undertake procedures requiring asepsis (PRAs), but report challenges and unwarranted variations in practice.

Objective: To explore nurses' experiences, perceived gaps in information and support needed to conduct PRAs.

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Hydrogels hold much promise for 3D printing of functional living materials; however, challenges remain in tailoring mechanical robustness as well as biological performance. In addressing this challenge, the modular synthesis of functional hydrogels from 3-arm diblock copolypeptide stars composed of an inner poly(l-glutamate) domain and outer poly(l-tyrosine) or poly(l-valine) blocks is described. Physical crosslinking due to ß-sheet assembly of these star block copolymers gives mechanical stability during extrusion printing and the selective incorporation of methacrylate units allows for subsequent photocrosslinking to occur under biocompatible conditions.

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