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Conjugated polymers (CPs) are promising semiconductors for intrinsically stretchable electronic devices. Ideally, such CPs should exhibit high charge mobility, excellent stability, and high stretchability. However, converging all these desirable properties in CPs has not been achieved via molecular design and/or device engineering. This work details the design, synthesis and characterization of a random polythiophene (RP-T50) containing ~50 mol% of thiophene units with a thermocleavable tertiary ester side chain and ~50 mol% of unsubstituted thiophene units, which, upon thermocleavage of alkyl chains, shows significant improvement of charge mobility and stability. Thermal annealing a RP-T50 film coated on a stretchable polydimethylsiloxane substrate spontaneously generates wrinkling in the polymer film, which effectively enhances the stretchability of the polymer film. The wrinkled RP-T50-based stretchable sensors can effectively detect humidity, ethanol, temperature and light even under 50% uniaxial and 30% biaxial strains. Our discoveries offer new design rationale of strategically applying CPs to intrinsically stretchable electronic systems. Conjugated polymers are promising semiconductors for stretchable electronic devices but combining important properties such as high charge mobility, stability and stretchability remains challenging. Here, the authors demonstrate the synthesis of a thiophene based semiconducting polymer with cleavable side chains which shows significant improvement of charge mobility, stability and stretchability.

The 2019–20 Australian fire season was heralded as emblematic of the catastrophic harm wrought by climate change. Similarly extreme wildfire seasons have occurred across the globe in recent years. Here, we apply a pyrogeographic lens to the recent Australian fires to examine the range of causes, impacts and responses. We find that the extensive area burnt was due to extreme climatic circumstances. However, antecedent hazard reduction burns (prescribed burns with the aim of reducing fuel loads) were effective in reducing fire severity and house loss, but their effectiveness declined under extreme weather conditions. Impacts were disproportionately borne by socially disadvantaged regional communities. Urban populations were also impacted through prolonged smoke exposure. The fires produced large carbon emissions, burnt fire-sensitive ecosystems and exposed large areas to the risk of biodiversity decline by being too frequently burnt in the future. We argue that the rate of change in fire risk delivered by climate change is outstripping the capacity of our ecological and social systems to adapt. A multi-lateral approach is required to mitigate future fire risk, with an emphasis on reducing the vulnerability of people through a reinvigoration of community-level capacity for targeted actions to complement mainstream fire management capacity.

BackgroundSimulations of fire spread are vital for operational fire management and strategic risk planning.AimsTo quantify burn heterogeneity effects on post-fire fuel loads, and test whether modifying fuel load estimates based on the fire severity and patchiness of the last fire improves the accuracy of simulations of subsequent fires.MethodsWe (1) measured fine fuels in eucalypt forests in south-eastern Australia following fires of differing severity; (2) modified post-fire fuel accumulation estimates based on our results; and (3) ran different fire simulations for a case-study area which was subject to a planned hazard reduction burn followed by a wildfire shortly thereafter.Key resultsIncreasing fire severity resulted in increased reduction in bark fuels. In contrast, surface and elevated fuels were reduced by similar amounts following both low-moderate and high-extreme fire severity. Accounting for burn heterogeneity, and fire severity effects on bark, improved the accuracy of fire spread for a case study fire.ConclusionsIntegration of burn heterogeneity into post-burn fuel load estimates may substantially improve fire behaviour predictions.ImplicationsWithout accounting for burn heterogeneity, patchy burns of low severity may mean that risk estimations are incorrect. This has implications for evaluating the cost-effectiveness of planned burn programmes.

Smoke pollution from landscape fires is a major health problem, but it is difficult to predict the impact of any particular fire. For example, smoke plumes can be mapped using remote sensing, but we do not know how the smoke is distributed in the air-column. Prescribed burning involves the deliberate introduction of smoke to human communities but the amount, composition, and distribution of the pollution may be different to wildfires. We examined whether mapped plumes produced high levels of particulate pollution (PM2.5) at permanent air quality monitors and factors that influenced those levels. We mapped 1237 plumes, all those observed in 17 years of MODIS imagery over New South Wales, Australia, but this was only ~20% of known fires. Prescribed burn plumes tended to occur over more populated areas than wildfires. Only 18% of wildfire plumes and 4% of prescribed burn plumes passed over a monitor (n = 115). A minority of plumes caused a detectable increase in PM2.5: prescribed burn plumes caused an air quality exceedance for 33% of observations in the daytime and 11% at night, wildfire plumes caused exceedances for 48% and 22% of observations in the day and night-time, respectively. Thus, most plumes remained aloft (did not reach the surface). Statistical modelling revealed that wind speed, temperature, and mixing height influenced whether a plume caused an exceedance, and there was a difference between prescribed and wild fires. In particular, in wind speeds below 1 kmhr−1, exceedance was almost certain in prescribed burns. This information will be useful for planning prescribed burning, preparing warnings, and improving our ability to predict smoke impacts.

Air quality was measured in Auburn, a western suburb of Sydney, Australia, for approximately eighteen months during 2016 and 2017. A long open-path infrared spectrometer sampled path-averaged concentrations of several gaseous species, while other pollutants such as PM 2.5 and PM 10 were sampled by a mobile air quality station. The measurement site was impacted by a number of indoor wood-heating smoke events during cold winter nights as well as some major smoke events from hazard reduction burning in the spring of 2017. In this paper we compare the atmospheric composition during these different smoke pollution events and assess the relative overall impact on air quality from domestic wood-heaters and prescribed forest fires during the campaign. No significant differences in the composition of smoke from these two sources were identified in this study. Despite the hazard reduction burning events causing worse peak pollution levels, we find that the overall exposure to air toxins was greater from domestic wood-heaters due to their higher frequency and total duration. Our results suggest that policy-makers should place a greater focus on reducing wood-smoke pollution in Sydney and on communicating the issue to the public.

Due to their unique properties, organic photovoltaics (OPVs) are more suitable than their inorganic counterparts in niche technologies requiring properties like flexibility, low-light/indoor efficiency, semi-transparency, and light weight. However, despite rapidly approaching the oft-cited 20% PCE benchmark for commercial viability, OPVs still lack the low cost and long lifetimes required for even niche applications. In this dissertation, we explored the contributions of processing, materials, and stability to the potential commercial viability of OPVs. We first aimed to demonstrate potential cost reduction through robustness against material variability. Through this and previous work with collaborators, we found that the morphologies (and PCEs) of systems using donor polymer PBnDT-FTAZ with various acceptors were insensitive to MWs ranging 30 kg/mol to 120 kg/mol. Such insensitivity can eliminate the need for tight MW control during synthesis, reducing costs. We then investigated the tolerance of OPVs to impurities. If material does not have to be entirely pure, this could be another cost reduction avenue. Using P3HT:PC61BM as a model system, we investigated the effect and ultimate fate of solid additives. We found the system was remarkably tolerant to a gamut of acidic, basic, neutral, and even ionic species. Furthermore, despite high melting and boiling points of these solid additives, they were largely absent in the bulk active layer following device fabrication. Thus, not only did this study demonstrate the remarkable additive tolerance of P3HT:PC61BM, but it also revealed that even high melting and boiling point solids may be volatilized and removed during typical OPV processing. Lastly, we explored methods of stabilizing morphology to increase lifetime. Utilizing P3HT copolymers integrating thermocleavable side chains (TCS), we demonstrated a polymer:fullerene system with remarkable thermal stability while maintaining PCE ~1.5%. As opposed to previous work wherein 100% of side chains were thermocleavable, this work demonstrated that a TCS density of 60% was more than sufficient for thermal stability while still affording appreciable PCE. Together, these works can inform OPV material selection and processing towards manufacture and use in commercial applications.

It is said that the love for your own child is one that cannot compare to any other feeling experienced. Most parents love their children unconditionally throughout their entire lifetime. Having a child and working diligently to raise them into a wellrounded human being is a task that all parents should be proud of. Often when a child grows they look for a life partner, someone whom they can have children with and the cycle goes on.

The Future of Youth Violence Prevention: A Mixtape for Practice, Policy, and Research  focuses on innovative approaches to youth violence prevention that utilize consistent principles found within existing best practices but are dynamic and adaptable across settings--and the sociohistorical and cultural realities of those settings.

Ms Dynamite, 24, famed for her anti-violence stance, was also charged by police with disorderly conduct while her brother, fellow rapper Akala, 22, was accused of obstruction. She refused to comment as she left the Central West End Police Station at 5:30pm. Ms Dynamite was seen enjoying an evening out with friends at the Umbaba nightclub in the West End on Thursday night. GIRLS ARE LOUD: Miss Dynamite and pals at Umbaba' WILD TIME: Ms Dynamite gets in mood for long night' IT'S A WRAP: Flower girl Ms Dynamite enjoys a hug' Pictures: TONY BRADY and WENN' NIGHTCLUB: The Paragon Lounge

Ms Dynamite, 24, famed for her anti-violence stance, was also charged with disorderly conduct while her brother, fellow rapper Akala, 22, was accused of obstruction. A friend of Ms Dynamite, from Archway, North London, claimed the star flew into a rage because of alleged rough treatment of her sister by club security staff. The friend said: \"That's why she was so angry and was kicking at the door.\" WILD TIME: Ms Dynamite gets in mood for long night' GIRLS ARE LOUD: Miss Dynamite and pals at Umbaba' IT'S A WRAP: Flower girl Ms Dynamite enjoys a hug' Pictures: TONY BRADY and WENN' BAIL: Ms D last night' NIGHTCLUB: Paragon Lounge