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Predation by invasive mammalian species is one of the key drivers of native species' population declines and extinctions. Current management of invasive species focuses on their removal from the landscape. However, total removal can be difficult, costly and even impossible. If eradication is not achieved, reductions in predator numbers are often temporary. New tactics are needed to target predators in situ, to reduce their negative impacts. We test the efficacy of conditioned taste aversion (CTA), a tactic that could reduce the impact of predation on target prey species. By associating nausea with a specific food source, it may be possible to condition an aversion to a target bait, and ultimately to live animals in the wild. To assess if wild invasive red foxes (Vulpes vulpes) can be conditioned to avoid a specific food source, we used baits (fried deboned chicken) containing encapsulated levamisole, an anthelmintic agent known to induce nausea leading to emesis and/or diarrhea at high dosages with no long‐term side effects. We buried baits at 30 stations across an open landscape. After treatment, reductions in control baits taken (at least 30%) were observed for 68 days, indicating the use of CTA had successfully reduced bait consumption by red foxes in a wild context. To our knowledge, this study represents the first successful test of CTA to a meat bait in a wild red fox population. Our results suggest that CTA shows promise as a tool to reduce the predation of vulnerable animals providing an alternative tactic to manage the impacts of invasive mammalian predators where eradication is currently impossible. [ABSTRACT FROM AUTHOR]

Predation of threatened fauna by native and introduced predators can drive extinction and prevent population recovery. Most predator management involves exclusion or culling. Evidence suggests that exclusion may have detrimental effects on a prey species' predator awareness. At the same time, culling can cause selection of control‐resistant predators. There is increasing interest in harnessing evolutionary processes to drive adaptation of threatened fauna to cope, but there is limited attention on trying this from the predator direction. We need to shift the survival advantage away from predators that avoid lethal control, and go on to kill, towards those that demonstrate behaviors that reduce impact on threatened fauna. Instead of driving undesirable predator selection, could we select through management actions desirable traits to make them "less lethal" to threatened fauna? We draw on experimental research on predator aversion that suggests there may be an alternative way to mitigate the impacts of predators, while maintaining the learning opportunities of prey species. Using the case study of the invasive red fox in Australia, we propose a conceptual framework within which future research and management could occur to select for these desirable traits in predators and develop practical regimes for predator impact mitigation. [ABSTRACT FROM AUTHOR]

Porous biodegradable scaffolds have many applications in bioengineering, ranging from cell culture and transplantation, to support structures, to induce blood vessel and tissue formation in vivo. While numerous strategies have been developed for the manufacture of porous scaffolds, it remains challenging to control the spatial organization of the pores. In this study, we introduce the use of the granular convection effect, also known as the muesli or brazil nut effect, to rapidly engineer particulate templates with a vertical size gradient. These templates can then be used to prepare scaffolds with pore size gradients. To demonstrate this approach, we prepared templates with particle size gradients, which were then infused with a prepolymer solution consisting of the pentaerythritol ethoxylate (polyol), sebacoyl chloride (acid chloride), and poly(caprolactone). Following curing, the template was dissolved to yield biodegradable polyester‐ether scaffolds with pore size gradients that could be tuned depending on the size range of the particulates used. The application of these scaffolds was demonstrated using pancreatic islets, which were loaded via centrifugation and retained within the scaffold's pores without a decrease in viability. The proposed strategy provides a facile approach to prepare templates with spatially organized pores that could potentially be used for cell transplantation, or guided tissue formation. [ABSTRACT FROM AUTHOR]

Antifogging and frost-resistant coatings can be used in a wide range of applications and enable high light transmission through substrates even under changes in environmental conditions. In this study, surface confined and cross-linked antifogging thin films are fabricated on glass slides via catalyst induced cross-linking (CIC), which has been recently introduced as an easy and efficient cross-linking methodology. Four different poly(ethylene glycol) (PEG)-based polymers with different hydrophilicity are synthesized and used to prepare films via CIC. Films prepared from the most hydrophilic PEG-based polymers display the best antifogging performances when exposed to a temperature change from −20 to 22 °C. Furthermore, several parameters including cross-linking density, surface roughness, hydrophobicity, and exposure time are also evaluated in terms of film transparency. Through these measurements, it is determined that, more loosely cross-linked films retain antifogging ability for longer time periods due to higher film swellability as compared to, more highly cross-linked films. This study signifies the crucial role of the film cross-linking density and hydrophilicity on the antifogging function. [ABSTRACT FROM AUTHOR]

Purpose: Microbeam radiation therapy (MRT) techniques are under investigation at synchrotrons worldwide. Favourable outcomes from animal and cell culture studies have proven the efficacy of MRT. The aim of MRT researchers currently is to progress to human clinical trials in the near future. The purpose of this study was to demonstrate the high resolution and 3D imaging of synchrotron generated microbeams in PRESAGE® dosimeters using laser fluorescence confocal microscopy. Methods:Water equivalent PRESAGE® dosimeters were fabricated and irradiated with microbeams on the Imaging and Medical Beamline at the Australian Synchrotron. Microbeam arrays comprised of microbeams 25-50 µm wide with 200 or 400 μm peak-to-peak spacing were delivered as single, cross-fire, multidirectional, and interspersed arrays. Imaging of the dosimeters was performed using a NIKON A1 laser fluorescence confocal microscope. Results: The spatial fractionation of the MRT beams was clearly visible in 2D and up to 9 mm in depth. Individual microbeams were easily resolved with the full width at half maximum of microbeams measured on images with resolutions of as low as 0.09 µm/pixel. Profiles obtained demonstrated the change of the peak-to-valley dose ratio for interspersed MRT microbeam arrays and subtle variations in the sample positioning by the sample stage goniometer were measured. Conclusions: Laser fluorescence confocal microscopy of MRT irradiated PRESAGE® dosimeters has been validated in this study as a high resolution imaging tool for the independent spatial and geometrical verification of MRT beam delivery. [ABSTRACT FROM AUTHOR]

Polypeptides have attracted widespread attention as building blocks for complex materials due to their ability to form higher-ordered structures such as β-sheets. However, the ability to precisely control the formation of well-defined β-sheet-assembled materials remains challenging as β-sheet formation tends to lead to ill-defined and unprocessable aggregates. This work reports a simple, rapid, and robust strategy to form well-defined peptide β-sheet-assembled shells (i.e., hollow spheres) by employing surface-initiated N-carboxyanhydride ring-opening polymerization under a highly efficient surface-driven approach. The concept is demonstrated by the preparation of enzyme-degradable rigid shell architectures composed of H-bonded poly(L-valine) (PVal) grafts with porous and sponge-like surface morphology. The porous PVal-shells exhibit a remarkable and unprecedented ability to non-covalently entrap metal nanoparticles, proteins, drug molecules, and biorelevant polymers, which could potentially lead to a diverse range of biodegradable and functional platforms for applications ranging from therapeutic delivery to organic catalysis. [ABSTRACT FROM AUTHOR]

The application of cyclodextrin (CD)-based host-guest interactions towards the fabrication of functional supramolecular assemblies and hydrogels is of particular interest in the field of biomedicine. However, as of late they have found new applications as advanced functional materials (e.g., actuators and self-healing materials), which have renewed interest across a wide range of fields. Advanced supramolecular materials synthesized using this noncovalent interaction, exhibit specificity and reversibility, which can be used to impart reversible cross-linking, specific binding sites, and functionality. In this review, various functional CD-based supramolecular assemblies and hydrogels will be outlined with the focus on recent advances. In addition, an outlook will be provided on the direction of this rapidly developing field. [ABSTRACT FROM AUTHOR]

The continuous assembly of polymers (CAP) is used to fabricate tailored nanocoatings on a wide variety of substrates. Ring-opening metathesis polymerization (ROMP) is used to mediate the CAP process (CAPROMP) to assemble specifically designed macromolecules into nanoengineered crosslinked films. Different films composed of single or multiple macromolecules are used to tune the surface wetting characteristics on various planar substrates, including porous substrates such as filter paper and cotton, and non-porous subtrates such as aluminium foil and glass. By judicious selection of the macromolecules, these substrates, which are hydrophilic in nature, can be rendered (super)hydrophobic. The robustness of the ROMP catalysts and the reinitiation ability of the CAPROMP approach allow the production of layered multicomponent amphiphilic films with on-demand switchable wettability. Such functional nanocoatings can be potentially applied as self-cleaning surfaces, as waterproof woven fabrics, and for the next generation of microelectronic devices. [ABSTRACT FROM AUTHOR]

ABSTRACT A series of novel amphiphilic diblock copolymers composed of hydrophilic linear poly(ethylene glycol) (PEG) and linear brush hydrophobic polydimethylsiloxane (PDMS) were synthesized. Three different molecular weights of monomethyl ether PEG were initially functionalized with 2-bromo isobutyryl bromide to afford macroinitiators suitable for atom-transfer radical polymerization. The macroinitiators were characterized by gel permeation chromatography, 1H and 13C nuclear magnetic resonance spectroscopic analysis and matrix-assisted laser desorption ionization time-of-flight mass spectroscopy. The three different molecular weight macroinitiators were then chain extended with monomethacryloxypropyl-terminated PDMS and photoactive 2-(methylacyloyloxy)ethyl anthracene-9-carboxylate in different molar ratios to afford a series of photoresponsive amphiphilic diblock copolymers with high conversions. Self-assembly of these linear-linear brush diblock copolymers in N, N-dimethylformamide afforded nanoparticles with hydrodynamic diameters ( dH) ranging from 41 to 268 nm, as determined by dynamic light scattering analysis. Crosslinking and stabilization of the nanoparticles was achieved via [4+4] photodimerization of the anthracene moieties upon exposure to UV radiation at 365 nm with the reverse reaction studied at a wavelength of 254 nm. Transmission electron microscopy revealed that the self-assembled nanoparticles and their crosslinked derivatives had spherical morphologies. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1251-1262 [ABSTRACT FROM AUTHOR]

In this study, the stereocomplexation between a novel stereospecific cyclic vinyl polymer, that is, cyclic syndiotactic poly(methyl methacrylate) ( st-PMMA), with the complementary linear isotactic ( it-) PMMA was investigated. Surprising new insight into the effects of the topology (i.e., end groups), size, and tacticity of the assembling components on stereocomplex formation was obtained. Characterization of the stereocomplexes revealed that the self-assembly of cyclic st-PMMAs and linear it-PMMAs resulted in the formation of an unprecedented 'polypseudorotaxane-type' supramolecular assembly. This stereocomplex exhibited remarkably different physical properties as compared to the conventional PMMA triple-helix stereocomplex as a result of the restricted topology imposed by the cyclic st-PMMA assembling component. [ABSTRACT FROM AUTHOR]

H‐bonded peptide β‐sheet‐assembled porous shells are prepared by a simple, rapid, and robust bottom‐up strategy involving controlled surface‐initiated ring‐opening polymerization. As reported by G. G. Qiao and co‐workers on page 3147, the exploitation of the hollow shells by non‐covalent interactions demonstrates the ability to entrap small molecules, nanoparticles, proteins, drugs, and polymers to form functional materials for various potential applications. [ABSTRACT FROM AUTHOR]

Front Cover: Cyclodextrin (CD)‐based host‐guest chemistry relies on specific, yet reversible non‐covalent interactions between CD and a guest. Using this interaction, CD host‐guest chemistry has been applied towards the fabrication of advanced functional assemblies and hydrogel materials. This review outlines new found applications using these materials which have renewed interest across a wide range of fields. Further details can be found in the article by S. Tan, K. Ladewig, Q. Fu, A. Blencowe* and G. Qiao* on page 1166. [ABSTRACT FROM AUTHOR]

The continuous assembly of polymers (CAP) is used to fabricate tailored nanocoatings on a wide variety of substrates. Ring-opening metathesis polymerization (ROMP) is used to mediate the CAP process (CAPROMP) to assemble specifically designed macromolecules into nanoengineered crosslinked films. Different films composed of single or multiple macromolecules are used to tune the surface wetting characteristics on various planar substrates, including porous substrates such as filter paper and cotton, and non-porous subtrates such as aluminium foil and glass. By judicious selection of the macromolecules, these substrates, which are hydrophilic in nature, can be rendered (super)hydrophobic. The robustness of the ROMP catalysts and the reinitiation ability of the CAP ROMP approach allow the production of layered multicomponent amphiphilic films with on-demand switchable wettability. Such functional nanocoatings can be potentially applied as self-cleaning surfaces, as waterproof woven fabrics, and for the next generation of microelectronic devices. [ABSTRACT FROM AUTHOR]