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PurposeTo estimate the prevalence of abnormalities in visual function and ocular structures associated with the long-term use of tamoxifen citrate.MethodsA single-masked, cross-sectional study involving multiple community and institutional ophthalmologic departments was conducted with a volunteer sample of 303 women with breast cancer currently taking part in a randomized clinical trial to determine the efficacy of tamoxifen (20 mg/day) in preventing recurrences. Participants included women who had never been on drug (n=85); women who had taken tamoxifen for an average of 4.8 years, then been off the drug for an average of 2.7 years (n=140); and women who had been on tamoxifen continuously for an average of 7.8 years (n=78). Women were evaluated by questionnaire, psychophysical testing, and clinical examination to determine any abnormalities in visual function and the comparative prevalences of corneal, lens, retinal, and optic nerve pathology.ResultsThere were no cases of vision-threatening ocular toxicity among the tamoxifen-treated participants. Compared with nontreated participants, the tamoxifen-treated women had no differences in the activities of daily vision, visual acuity measurements, or other tests of visual function except for color screening. Intraretinal crystals (odds ratio [OR]=3.58, P=.178) and posterior subcapsular opacities (OR=4.03, P=.034) were more frequent in the tamoxifen-treated group.ConclusionsWomen should have a thorough baseline ophthalmic evaluation within the first year of initiating tamoxifen therapy and receive appropriate follow-up evaluations.

Newborn screening (NBS) programs are a well established and cost-effective method for early identification of genetic disorders. However, a raft of legal questions surrounds the collection, storage, ownership and secondary use of NBS cards. The absence of clear legal rules governing NBS programs in Australia means that there are few straightforward answers to these questions. A series of controversial incidents have exposed this uncertainty in Australia, and remarkably similar controversies have occurred in the United States and European Union. We review the situation, using Victoria as a case study. We also make the case for a dedicated regulatory regime for NBS programs, arguing that the lack of such a regime threatens public trust and the robust operation of NBS programs in Australia. New rules would likely introduce stricter requirements for informed consent at the point of blood collection than has been the norm to date. However, the scope for use of cards in research could expand rather than contract, and it may be possible to reduce the risk that vast card archives will need to be destroyed in response to future public outcries. [ABSTRACT FROM AUTHOR]

Based on the experiences of two high profile voluntary data collection programs for engineered nanomaterials, this article considers the merit of an international online registry for scientific data on engineered nanomaterials and environmental, health and safety (EHS) data. Drawing on the earlier experiences from the pharmaceutical industry, the article considers whether a registry of nanomaterials at the international level is practical or indeed desirable, and if so, whether such an initiative--based on the current state of play--should be voluntary or mandatory. The article commences with an examination of the success and failures of voluntary reporting schemes in the UK and the US, as well as the International Council of Nanotechnology's EHS Database and the OECD's Working Party on Manufactured Nanomaterials. The article then examines the history of clinical trials registries, including the key motivations behind their creation, the role of self-regulation, and the perceived benefits thereof. Key lessons of the rise of clinical trials registration are highlighted, as are crucial considerations that must be addressed by policy makers should a multi-lateral public registry for data on nanoscale materials and EHS research be perceived to be a desirable option. The article concludes by arguing that while the creation of a registry to record information generated on nanomaterials is not straightforward, this reason alone should not deter industry from taking a proactive approach to the dissemination of fundamental data and research findings. [ABSTRACT FROM AUTHOR]

Background: In 1982, the National Surgical Adjuvant Breast and Bowel Project initiated a randomized, double-blinded, placebo-controlled trial (B-14) to determine the effectiveness of adjuvant tamoxifen therapy in patients with primary operable breast cancer who had estrogen receptor-positive tumors and no axillary lymph node involvement. The findings indicated that tamoxifen therapy provided substantial benefit to patients with early stage disease. However, questions arose about how long the observed benefit would persist, about the duration of therapy necessary to maintain maximum benefit, and about the nature and severity of adverse effects from prolonged treatment.Purpose: We evaluated the outcome of patients in the B-14 trial through 10 years of follow-up. In addition, the effects of 5 years versus more than 5 years of tamoxifen therapy were compared.Methods: In the trial, patients were initially assigned to receive either tamoxifen at 20 mg/day (n = 1404) or placebo (n = 1414). Tamoxifen-treated patients who remained disease free after 5 years of therapy were then reassigned to receive either another 5 years of tamoxifen (n = 322) or 5 years of placebo (n = 321). After the study began, another group of patients who met the same protocol eligibility requirements as the randomly assigned patients were registered to receive tamoxifen (n = 1211). Registered patients who were disease free after 5 years of treatment were also randomly assigned to another 5 years of tamoxifen (n = 261) or to 5 years of placebo (n = 249). To compare 5 years with more than 5 years of tamoxifen therapy, data relating to all patients reassigned to an additional 5 years of the drug were combined. Patients who were not reassigned to either tamoxifen or placebo continued to be followed in the study. Survival, disease-free survival, and distant disease-free survival (relating to failure at distant sites) were estimated by use of the Kaplan-Meier method; differences between the treatment groups were assessed by use of the logrank test. The relative risks of failure (with 95% confidence intervals [CIs]) were determined by use of the Cox proportional hazards model. Reported P values are two-sided.Results: Through 10 years of follow-up, a significant advantage in disease-free survival (69% versus 57%, P < .0001; relative risk = 0.66; 95% CI = 0.58-0.74), distant disease-free survival (76% versus 67%, P < .0001; relative risk = 0.70; 95% CI = 0.61-0.81), and survival (80% versus 76%, P = .02; relative risk = 0.84; 95% CI = 0.71-0.99) was found for patients in the group first assigned to receive tamoxifen. The survival benefit extended to those 49 years of age or younger and to those 50 years of age or older. Tamoxifen therapy was associated with a 37% reduction in the incidence of contralateral (opposite) breast cancer (P = .007). Through 4 years after the reassignment of tamoxifen-treated patients to either continued-therapy or placebo groups, advantages in disease-free survival (92% versus 86%, P = .003) and distant disease-free survival (96% versus 90%, P = .01) were found for those who discontinued tamoxifen treatment. Survival was 96% for those who discontinued tamoxifen compared with 94% for those who continued tamoxifen treatment (P = .08). A higher incidence of thromboembolic events was seen in tamoxifen-treated patients (through 5 years, 1.7% versus 0.4%). Except for endometrial cancer, the incidence of second cancers was not increased with tamoxifen therapy.Conclusions and Implications: The benefit from 5 years of tamoxifen therapy persists through 10 years of follow-up. No additional advantage is obtained from continuing tamoxifen therapy for more than 5 years. [ABSTRACT FROM AUTHOR]

Introduction: Older adults represent the fastest growing segment of the homeless community. Little is known about the prevalence of dementia and mild cognitive impairment (MCI) in this population., Methods: Dementia and MCI screening using the Montreal Cognitive Assessment (MoCA) was incorporated into the standard senior evaluation for adult clients aged ≥ 55 in a large emergency homeless shelter., Results: In a 6-week period, 104 of 112 (92.9%) assessments were positive for dementia or MCI using a standard cutoff of 26, and 81 (72.3%) were positive using a conservative cutoff of 23. There was no significant difference in MoCA scores based on sex or education level, and no significant correlation between age and MoCA score., Discussion: Older adults experiencing homelessness may have a high likelihood of dementia or MCI. Routine MoCA screening in older adults experiencing homelessness is feasible and can help to identify services needed to successfully exit homelessness., (© 2024 The Authors. Alzheimer's & Dementia published by Wiley Periodicals LLC on behalf of Alzheimer's Association.)

Massive stars (those ≥8 solar masses at formation) have radiative envelopes that cannot sustain a dynamo, the mechanism that produces magnetic fields in lower-mass stars. Despite this, approximately 7% of massive stars have observed magnetic fields, the origin of which is debated. We used multi-epoch interferometric and spectroscopic observations to characterize HD 148937, a binary system of two massive stars. We found that only one star is magnetic and that it appears younger than its companion. The system properties and a surrounding bipolar nebula can be reproduced with a model in which two stars merged (in a previous triple system) to produce the magnetic massive star. Our results provide observational evidence that magnetic fields form in at least some massive stars through stellar mergers.

Magnetars are highly magnetized neutron stars, the formation mechanism of which is unknown. Hot helium-rich stars with spectra dominated by emission lines are known as Wolf-Rayet stars. We observed the binary system HD 45166 using spectropolarimetry and reanalyzed its orbit using archival data. We found that the system contains a Wolf-Rayet star with a mass of 2 solar masses and a magnetic field of 43 kilogauss. Stellar evolution calculations indicate that this component will explode as a supernova, and that its magnetic field is strong enough for the supernova to leave a magnetar remnant. We propose that the magnetized Wolf-Rayet star formed by the merger of two lower-mass helium stars.

Over the past 5 years, advanced assisted reproductive technologies (ARTs), such as mitochondrial replacement therapies (MRTs) and heritable human genome editing (HHGE), have raised global policy concerns and fears of 'unregulated' proliferation. Yet, few innovations are ever truly unregulated and more often fall within the scope of one or more pre-existing regulatory regimes, a process referred to as 'inherited regulation'. While the United Kingdom has enacted new legislation to specifically authorize and closely regulate MRTs, many jurisdictions will likely default to current oversight systems to manage advanced ARTs. This article evaluates and compares how several jurisdictions have already used four types of inherited regulatory regimes to manage MRTs and HHGE. Cases are drawn from jurisdictions where inherited regulatory interventions on advanced ARTs have taken place (USA, Greece, Ukraine, China, and Russia) and include jurisdictions closely connected with those cases (Mexico and Spain). When accounting for political, cultural, and religious contexts, many of these inherited regimes offer promise as starting points for governance of advanced ARTs, yet each will require further adjustments and tailoring to adequately manage the benefits and risks of these powerful innovations., (© The Author(s) 2022. Published by Oxford University Press on behalf of Duke University School of Law, Harvard Law School, Oxford University Press, and Stanford Law School.)

Microvillus inclusion disease (MVID) is a congenital diarrheal disorder resulting in life-threatening secretory diarrhea in newborns. Inactivating and nonsense mutations in myosin Vb (MYO5B) have been identified in MVID patients. Work using patient tissues, cell lines, mice, and pigs has led to critical insights into the pathology of MVID and a better understanding of both apical trafficking in intestinal enterocytes and intestinal stem cell differentiation. These studies have demonstrated that loss of MYO5B or inactivating mutations lead to loss of apical sodium and water transporters, without loss of apical CFTR, accounting for the major pathology of the disease. In addition, loss of MYO5B expression induces the formation of microvillus inclusions through apical bulk endocytosis that utilizes dynamin and PACSIN2 and recruits tight junction proteins to the sites of bulk endosome formation. Importantly, formation of microvillus inclusions is not required for the induction of diarrhea. Recent investigations have demonstrated that administration of lysophosphatidic acid (LPA) can partially reestablish apical ion transporters in enterocytes of MYO5B KO mice. In addition, further studies have shown that MYO5B loss induces an imbalance in Wnt/Notch signaling pathways that can lead to alterations in enterocyte maturation and tuft cell lineage differentiation. Inhibition of Notch signaling leads to improvements in those cell differentiation deficits. These studies demonstrate that directed strategies through LPA receptor activation and Notch inhibition can bypass the inhibitory effects of MYO5B loss. Thus, effective strategies may be successful in MVID patients and other congenital diarrhea syndromes to reestablish proper apical membrane absorption of sodium and water in enterocytes and ameliorate life-threatening congenital diarrhea., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

This paper provides an overview of the societal impact of a rising dementia population and examines the legal and ethical implications posed by voluntary registries as a community-oriented solution to improve interactions between law enforcement and individuals with dementia. It provides a survey of active voluntary registries across the United States, with a focus on Arizona, which has the highest projected growth for individuals living with dementia in the country.

Medical testing promises to establish certainty by providing a definitive assessment of risk or diagnosis. But can those who rely on tests to offer advice or make clinical decisions be assured of this certainty? This article examines how Australian health professionals, namely clinicians, microbiologists, specialist physicians and health policymakers, delineate the boundary between certainty and uncertainty in their accounts of medical testing. Applying concepts from science and technology studies, and drawing on qualitative data from a sociological study of testing in Australian healthcare, we consider how professionals ascribe meaning to testing and test results. As we argue, for these health professionals, the 'evidence' that testing generates has ambiguous ontological significance: while it promises to provide diagnostic certainty and clear direction for advice or treatment, it also generates uncertainties that may lead to yet further tests. Our analysis leads us to question a key premise of testing, namely that it is possible to establish certainty in medical practice via the measurement of individual health risks and disease markers. Against this dominant view, the responses of the health professionals in our study suggest that uncertainty is intrinsic to testing due to the constantly changing, unstable character of 'evidence'. We conclude by considering the implications of our analysis in light of healthcare's increasing reliance on sophisticated technologies of 'personalised' testing using genetic information and data analytics.

Many countries, including Australia, the United Kingdom and the United States have established national screening programs in the effort to advance the early diagnosis of cancers. Australia has population screening programs for breast, bowel and cervical cancers, and this article focuses on breast and cervical cancer screening as the two longest running programs in Australia. While these screening programs are well-established and report relatively high participation rates, the effectiveness of population screening is a contested issue, subject to significant, ongoing debate about its purported benefits (Armstrong, 2019). In this article, we draw on ideas from sociology of science on the construction of scientific facts to analyse how evidentiary claims are presented in policy documents for Australia's breast and cervical cancer screening programs, and the implications for those who are the targets of screening. We explore how screening-related information assumes the status of scientific 'facts', and argue that presenting information as neutral and objective obscures the political choices involved in its generation. Importantly, some of the claims presented in the policy documents have a tendency to emphasise the benefits, and minimise the risks and harms of population-based screening. In doing so, we suggest that the current national policies may be contributing to sustaining expectations of screening that are higher than warranted. Higher expectations may bring with them unintended societal and economic costs to the public. We conclude by noting how deeply ingrained socio-cultural meanings of cancer shape public expectations of the protective value of screening, which allows current screening approaches to become further entrenched and resistant to challenge., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Responsible research and innovation (RRI) has come to represent a change in the relationship between science, technology and society. With origins in the democratisation of science, and the inclusion of ethical and societal aspects in research and development activities, RRI offers a means of integrating society and the research and innovation communities. In this article, we frame RRI activities through the lens of layers of science and technology governance as a means of characterising the context in which the RRI activity is positioned and the goal of those actors promoting the RRI activities in shaping overall governance patterns. RRI began to emerge during a time of considerable deliberation about the societal and governance challenges around nanotechnology, in which stakeholders were looking for new ways of integrating notions of responsibility in nanotechnology research and development. For this reason, this article focuses on nanotechnology as the site for exploring the evolution and growth of RRI.

The small rainforest fragments found in savanna landscapes are powerful, yet often overlooked, model systems to understand the controls of these contrasting ecosystems. We analyzed the relative effect of climatic variables on rainforest density at a subcontinental level, and employed high-resolution, regional-level analyses to assess the importance of landscape settings and fire activity in determining rainforest density in a frequently burnt Australian savanna landscape. Estimates of rainforest density (ha/km 2 ) across the Northern Territory and Western Australia, derived from preexisting maps, were used to calculate the correlations between rainforest density and climatic variables. A detailed map of the northern Kimberley (Western Australia) rainforests was generated and analyzed to determine the importance of geology and topography in controlling rainforests, and to contrast rainforest density on frequently burnt mainland and nearby islands. In the northwestern Australian, tropics rainforest density was positively correlated with rainfall and moisture index, and negatively correlated with potential evapotranspiration. At a regional scale, rainforests showed preference for complex topographic positions and more fertile geology. Compared with mainland areas, islands had significantly lower fire activity, with no differences between terrain types. They also displayed substantially higher rainforest density, even on level terrain where geomorphological processes do not concentrate nutrients or water. Our multi-scale approach corroborates previous studies that suggest moist climate, infrequent fires, and geology are important stabilizing factors that allow rainforest fragments to persist in savanna landscapes. These factors need to be incorporated in models to predict the future extent of savannas and rainforests under climate change.

The patent landscape, like a garden, can tell you much about its designers and users; their motivations, biases, and general interests. While both patent landscapes and gardens may appear to the casual observer as refined and ordered, an in-depth exploration of the terrain is likely to reveal unforeseen challenges including, for example, alien species, thickets, and trolls. As this Chapter illustrates, patent landscapes are dynamic and have been forced to continually evolve in response to technological innovation. While emerging technologies, such as biotechnology and information communication technology have challenged the traditional patent landscape, resulting in the pruning of certain elements here and there, the overarching framework and design has largely remained intact. But will this always be the case? As the field of nanotechnology continues to evolve and mature, the aim of this Chapter is to map how the technology has evolved and grown within the confines of existing structures and underlying foundation of the patent landscape and the implications thereof for the technology, industry, and the public more generally. The Chapter concludes by asking the question whether the current patent landscape will be able to withstand the ubiquitous nature of the technology, or whether nanotechnology, in combination with other emerging technologies, will be a catalyst for governments and policy makers to completely redesign the patent landscape.

Zika infection in pregnant women is associated with an elevated probability of giving birth to a child with microcephaly and multiple other disabilities. Public health messaging on Zika prevention has predominantly targeted women who know they are pregnant or intend to become pregnant, but not teenage females for whom unintended pregnancy is more likely. Vulnerabilities among this population to reproductive risks associated with Zika are further amplified by restrictive abortion laws in several Zika-impacted states. Key to prevention is enhanced, targeted public health messaging centered on teens nationally and particularly in certain high-risk regions.

Global increases in fire frequency driven by anthropogenic greenhouse emissions and land use change could threaten unique and ancient species by creeping into long-term fire refugia. The perhumid and mountainous western half of Tasmania is a globally important refugium for palaeo-endemic, fire intolerant lineages, especially conifers. Reproductive strategy will be crucial to the resilience of these organisms under warmer, dryer and more fire prone climates. This study analysed clonal versus sexual reproduction in old growth plots dominated by the palaeo-endemic conifer Athrotaxis cupressoides (Cupressaceae), a species that lacks any traits to tolerate frequent landscape fire. Across most of the seven plots the amount of sexually derived individuals was lower than clonally derived with, on average, 60% of all stems belonging to the same multi-locus lineage (MLL) (i.e. were clonal). Some MLLs were large spanning over 10 s of metres and consisted of up to 62 stems. The high mortality after fire and the rarity of sexual regeneration means that the range of this fire-intolerant species is likely to contract under enhanced fire regimes and has a limited capacity to disperse via seed to available fire refugia in the landscape.

Humans use combustion for heating and cooking, managing lands, and, more recently, for fuelling the industrial economy. As a shift to fossil-fuel-based energy occurs, we expect that anthropogenic biomass burning in open landscapes will decline as it becomes less fundamental to energy acquisition and livelihoods. Using global data on both fossil fuel and biomass burning emissions, we tested this relationship over a 14 year period (1997-2010). The global average annual carbon emissions from biomass burning during this time were 2.2 Pg C per year (±0.3 s.d.), approximately one-third of fossil fuel emissions over the same period (7.3 Pg C, ±0.8 s.d.). There was a significant inverse relationship between average annual fossil fuel and biomass burning emissions. Fossil fuel emissions explained 8% of the variation in biomass burning emissions at a global scale, but this varied substantially by land cover. For example, fossil fuel burning explained 31% of the variation in biomass burning in woody savannas, but was a non-significant predictor for evergreen needleleaf forests. In the land covers most dominated by human use, croplands and urban areas, fossil fuel emissions were more than 30- and 500-fold greater than biomass burning emissions. This relationship suggests that combustion practices may be shifting from open landscape burning to contained combustion for industrial purposes, and highlights the need to take into account how humans appropriate combustion in global modelling of contemporary fire. Industrialized combustion is not only an important driver of atmospheric change, but also an important driver of landscape change through companion declines in human-started fires.This article is part of the themed issue 'The interaction of fire and mankind'., (© 2016 The Author(s).)

Fire positively and negatively affects food webs across all trophic levels and guilds and influences a range of ecological processes that reinforce fire regimes, such as nutrient cycling and soil development, plant regeneration and growth, plant community assembly and dynamics, herbivory and predation. Thus we argue that rather than merely describing spatio-temporal patterns of fire regimes, pyrodiversity must be understood in terms of feedbacks between fire regimes, biodiversity and ecological processes. Humans shape pyrodiversity both directly, by manipulating the intensity, severity, frequency and extent of fires, and indirectly, by influencing the abundance and distribution of various trophic guilds through hunting and husbandry of animals, and introduction and cultivation of plant species. Conceptualizing landscape fire as deeply embedded in food webs suggests that the restoration of degraded ecosystems requires the simultaneous careful management of fire regimes and native and invasive plants and animals, and may include introducing new vertebrates to compensate for extinctions that occurred in the recent and more distant past.This article is part of the themed issue 'The interaction of fire and mankind'., (© 2016 The Author(s).)

Air pollution from landscape fires, domestic fires and fossil fuel combustion is recognized as the single most important global environmental risk factor for human mortality and is associated with a global burden of disease almost as large as that of tobacco smoking. The shift from a reliance on biomass to fossil fuels for powering economies, broadly described as the pyric transition, frames key patterns in human fire usage and landscape fire activity. These have produced distinct patters of human exposure to air pollution associated with the Agricultural and Industrial Revolutions and post-industrial the Earth global system-wide changes increasingly known as the Anthropocene. Changes in patterns of human fertility, mortality and morbidity associated with economic development have been previously described in terms of demographic, epidemiological and nutrition transitions, yet these frameworks have not explicitly considered the direct consequences of combustion emissions for human health. To address this gap, we propose a pyrohealth transition and use data from the Global Burden of Disease (GBD) collaboration to compare direct mortality impacts of emissions from landscape fires, domestic fires, fossil fuel combustion and the global epidemic of tobacco smoking. Improving human health and reducing the environmental impacts on the Earth system will require a considerable reduction in biomass and fossil fuel combustion.This article is part of the themed issue 'The interaction of fire and mankind'., (© 2016 The Author(s).)

Although grass pollen is widely regarded as the major outdoor aeroallergen source in Australia and New Zealand (NZ), no assemblage of airborne pollen data for the region has been previously compiled. Grass pollen count data collected at 14 urban sites in Australia and NZ over periods ranging from 1 to 17 years were acquired, assembled and compared, revealing considerable spatiotemporal variability. Although direct comparison between these data is problematic due to methodological differences between monitoring sites, the following patterns are apparent. Grass pollen seasons tended to have more than one peak from tropics to latitudes of 37°S and single peaks at sites south of this latitude. A longer grass pollen season was therefore found at sites below 37°S, driven by later seasonal end dates for grass growth and flowering. Daily pollen counts increased with latitude; subtropical regions had seasons of both high intensity and long duration. At higher latitude sites, the single springtime grass pollen peak is potentially due to a cooler growing season and a predominance of pollen from C 3 grasses. The multiple peaks at lower latitude sites may be due to a warmer season and the predominance of pollen from C 4 grasses. Prevalence and duration of seasonal allergies may reflect the differing pollen seasons across Australia and NZ. It must be emphasized that these findings are tentative due to limitations in the available data, reinforcing the need to implement standardized pollen-monitoring methods across Australasia. Furthermore, spatiotemporal differences in grass pollen counts indicate that local, current, standardized pollen monitoring would assist with the management of pollen allergen exposure for patients at risk of allergic rhinitis and asthma.

Wildland fire management has reached a crossroads. Current perspectives are not capable of answering interdisciplinary adaptation and mitigation challenges posed by increases in wildfire risk to human populations and the need to reintegrate fire as a vital landscape process. Fire science has been, and continues to be, performed in isolated "silos," including institutions (e.g., agencies versus universities), organizational structures (e.g., federal agency mandates versus local and state procedures for responding to fire), and research foci (e.g., physical science, natural science, and social science). These silos tend to promote research, management, and policy that focus only on targeted aspects of the "wicked" wildfire problem. In this article, we provide guiding principles to bridge diverse fire science efforts to advance an integrated agenda of wildfire research that can help overcome disciplinary silos and provide insight on how to build fire-resilient communities.

Premise of the Study: Homoploid hybrid speciation is receiving growing attention due the increasing recognition of its role in speciation. We investigate if individuals intermediate in morphology between the two species of the conifer genus Athrotaxis represent a homoploid hybrid species, A. laxifolia, or are spontaneous F1 hybrids., Methods: A total of 1055 individuals of Athrotaxis cupressoides and A. selaginoides, morphologically intermediate individuals, and two putative hybrid swarms were sampled across the range of the genus and genotyped with 13 microsatellites. We used simulations to test the power of our data to identify the pure species, F1s, F2s, and backcross generations., Key Results: We found that Athrotaxis cupressoides and A. selaginoides are likely the most divergent congeneric conifers known, but the intermediates are F1 hybrids, sharing one allele each from A. cupressoides and A. selaginoides at six loci with completely species specific alleles. The hybrid swarms contain wide genetic variation with stronger affinities to the locally dominant species, A. selaginoides and A. selaginoides backcrosses outnumbering A. cupressoides backcrosses. In addition, we observed evidence for isolated advanced generation backcrosses within the range of the pure species., Conclusions: We conclude that, even though they can be large and long-lived, Athrotaxis hybrid swarms are on a trajectory of decline and will eventually be reabsorbed by the parental species. However, this process may take millennia and fossil evidence suggests that such events have occurred repeatedly since the early Quaternary. Given this timeline, our study highlights the many obstacles to homoploid hybrid speciation., (© 2016 Botanical Society of America.)

Metal oxide nanoparticles in sunscreens provide broad-spectrum ultraviolet protection to skin. All studies to assess dermal penetration of nanoparticles have unanimously concluded that the overwhelming majority of nanoparticles remain on the outer surface of the skin. However, possibly due to many different experimental protocols in use, conclusions over the potential penetration to viable skin are mixed. Here, we review several factors that may influence experimental results for dermal penetration including the species studied (human, or animal model), size and coating of the metal oxide nanoparticles, composition of the sunscreen formulation, site of sunscreen application, dose and number of applications, duration of the study, types of biological samples analysed, methods for analysing samples, exposure to UV and skin flexing. Based on this information, we suggest an appropriate research agenda involving international collaboration that maximises the potential for dermal absorption of nanoparticles, and their detection, under normal conditions of sunscreen use by humans. If results from this research agenda indicate no absorption is observed, then concerns over adverse health effects from the dermal absorption of nanoparticles in sunscreens may be allayed.

Tracking the response of forest ecosystems to climate change demands large (≥1 ha) monitoring plots that are repeatedly measured over long time frames and arranged across macro-ecological gradients. Continental scale networks of permanent forest plots have identified links between climate and carbon fluxes by monitoring trends in tree growth, mortality and recruitment. The relationship between tree growth and climate in Australia has been recently articulated through analysis of data from smaller forest plots, but conclusions were limited by (a) absence of data on recruitment and mortality, (b) exclusion of non-eucalypt species, and (c) lack of knowledge of stand age or disturbance histories. To remedy these gaps we established the Ausplots Forest Monitoring Network: a continental scale network of 48 1 ha permanent plots in highly productive tall eucalypt forests in the mature growth stage. These plots are distributed across cool temperate, Mediterranean, subtropical and tropical climates (mean annual precipitation 850 to 1900 mm per year; mean annual temperature 6 to 21°C). Aboveground carbon stocks (AGC) in these forests are dominated by eucalypts (90% of AGC) whilst non-eucalypts in the understorey dominated species diversity and tree abundance (84% of species; 60% of stems). Aboveground carbon stocks were negatively related to mean annual temperature, with forests at the warm end of the temperature range storing approximately half the amount of carbon as forests at the cool end of the temperature range. This may reflect thermal constraints on tree growth detected through other plot networks and physiological studies. Through common protocols and careful sampling design, the Ausplots Forest Monitoring Network will facilitate the integration of tall eucalypt forests into established global forest monitoring initiatives. In the context of projections of rapidly warming and drying climates in Australia, this plot network will enable detection of links between climate and growth, mortality and carbon dynamics of eucalypt forests.

Ultraviolet radiation is recognized as a human carcinogen by the International Agency for Research on Cancer, the world's authority on cancer research. In particular, exposure to ultraviolet radiation can lead to melanoma of the skin, which is the deadliest form of skin cancer in the United States. Yet despite the significant public health burden that is associated with skin cancer in the United States, each year over a million Americans engage in indoor tanning where exposure to artificial ultraviolet radiation occurs. In this article, we argue for an immediate ban on the use of commercial indoor tanning by minors and, based on international precedents, the phasing out of all commercial tanning operations in the United States. We consider the use of indoor tanning devices in the United States, epidemiological data on indoor tanning devices and cancer, regulation of tanning devices, and scientific evidence for increased government intervention., (© The Author(s) 2015.)

Climate strongly influences global wildfire activity, and recent wildfire surges may signal fire weather-induced pyrogeographic shifts. Here we use three daily global climate data sets and three fire danger indices to develop a simple annual metric of fire weather season length, and map spatio-temporal trends from 1979 to 2013. We show that fire weather seasons have lengthened across 29.6 million km(2) (25.3%) of the Earth's vegetated surface, resulting in an 18.7% increase in global mean fire weather season length. We also show a doubling (108.1% increase) of global burnable area affected by long fire weather seasons (>1.0 σ above the historical mean) and an increased global frequency of long fire weather seasons across 62.4 million km(2) (53.4%) during the second half of the study period. If these fire weather changes are coupled with ignition sources and available fuel, they could markedly impact global ecosystems, societies, economies and climate.

Alternative stable-state theory (ASS) is widely accepted as explaining landscape-level vegetation dynamics, such as switches between forest and grassland. This theory argues that webs of feedbacks stabilise vegetation composition and structure, and that abrupt state shifts can occur if stabilising feedbacks are weakened. However, it is difficult to identify stabilising feedback loops and the disturbance thresholds beyond which state changes occur. Here, we argue that doing this requires a synthetic approach blending observation, experimentation, simulation, conceptual models, and narratives. Using forest boundaries and large mammal extinctions, we illustrate how a multifaceted research program can advance understanding of feedback-driven ecosystem change. Our integrative approach has applicability to other complex macroecological systems controlled by numerous feedbacks where controlled experimentation is impossible., (Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.)

Despite the challenges wildland fire poses to contemporary resource management, many fire-prone ecosystems have adapted over centuries to millennia to intentional landscape burning by people to maintain resources. We combine fieldwork, modeling, and a literature survey to examine the extent and mechanism by which anthropogenic burning alters the spatial grain of habitat mosaics in fire-prone ecosystems. We survey the distribution of Callitris intratropica, a conifer requiring long fire-free intervals for establishment, as an indicator of long-unburned habitat availability under Aboriginal burning in the savannas of Arnhem Land. We then use cellular automata to simulate the effects of burning identical proportions of the landscape under different fire sizes on the emergent patterns of habitat heterogeneity. Finally, we examine the global extent of intentional burning and diversity of objectives using the scientific literature. The current distribution of Callitris across multiple field sites suggested long-unburnt patches are common and occur at fine scales (<0.5 ha), while modeling revealed smaller, patchy disturbances maximize patch age diversity, creating a favorable habitat matrix for Callitris. The literature search provided evidence for intentional landscape burning across multiple ecosystems on six continents, with the number of identified objectives ranging from two to thirteen per study. The fieldwork and modeling results imply that the occurrence of long-unburnt habitat in fire-prone ecosystems may be an emergent property of patch scaling under fire regimes dominated by smaller fires. These findings provide a model for understanding how anthropogenic burning alters spatial and temporal aspects of habitat heterogeneity, which, as the literature survey strongly suggests, warrant consideration across a diversity of geographies and cultures. Our results clarify how traditional fire management shapes fire-prone ecosystems, which despite diverse objectives, has allowed human societies to cope with fire as a recurrent disturbance.

In an unprecedented legal ruling in June 2013, a US federal district court judge decided that the existing policy for donor lung allocation be vacated to save the life of a ten-year-old girl dying from cystic fibrosis. This case has fueled much controversy in the United States among policy makers, ethicists, and physicians who treat other patients awaiting transplant. This article examines the creation of the current US lung allocation policy and its impact on outcomes and analyzes the multidimensionality of the ruling. After analyzing the current policy and investigating alternatives for donor pool expansion, the article concludes by articulating options that may mitigate the need for current policy revision., (Copyright © 2015 by Duke University Press.)

Eucalyptus obliqua, the most widespread timber tree in Tasmania, is a pioneer after fire which can eliminate the organic layer of forest soil, exposing the underlying mineral soil. We compared seedling growth, mycorrhiza formation, and mineral nutrient limitation in organic layer vs. mineral soil. We grew E. obliqua seedlings separately in pots of organic layer and mineral soil in a glasshouse. Additional treatments of organic soil only, involved fully crossed methyl-bromide fumigation and fertilization. Fertilization comprised chelated iron for 121 days after transplant (DAT) followed by soluble phosphorus. At 357 DAT, whole plant dry weight was three times greater in ambient organic than in mineral soil. In organic soil, fumigation halved ectomycorrhiza abundance and reduced seedling growth at 149 DAT, but by 357 DAT when negative effects of fumigation on seedling growth had disappeared, neither fumigation nor fertilization affected mycorrhiza abundance. Iron fertilization diminished seedling growth, but subsequent phosphorus fertilization improved it. E. obliqua seedlings grow much better in organic layer soil than in mineral soil, although phosphorus remains limiting. The prevalent forestry practice of burning to mineral soil after timber harvest exposes a poor growth medium likely only partially compensated by fire-induced mineral soil alterations.

Objective: Allergic rhinitis and allergic asthma are important chronic diseases posing serious public health issues in Australia with associated medical, economic, and societal burdens. Pollen are significant sources of clinically relevant outdoor aeroallergens, recognised as both a major trigger for, and cause of, allergic respiratory diseases. This study aimed to provide a national, and indeed international, perspective on the state of Australian pollen data using a large representative sample., Methods: Atmospheric grass pollen concentration is examined over a number of years within the period 1995 to 2013 for Brisbane, Canberra, Darwin, Hobart, Melbourne, and Sydney, including determination of the 'clinical' grass pollen season and grass pollen peak., Results: The results of this study describe, for the first time, a striking spatial and temporal variability in grass pollen seasons in Australia, with important implications for clinicians and public health professionals, and the Australian grass pollen-allergic community., Conclusions: These results demonstrate that static pollen calendars are of limited utility and in some cases misleading. This study also highlights significant deficiencies and limitations in the existing Australian pollen monitoring and data., Implications: Establishment of an Australian national pollen monitoring network would help facilitate advances in the clinical and public health management of the millions of Australians with asthma and allergic rhinitis., (© 2015 The Authors © 2015 Public Health Association of Australia.)

Athrotaxis cupressoides is a slow-growing and long-lived conifer that occurs in the subalpine temperate forests of Tasmania, a continental island to the south of Australia. In 1960-1961, human-ignited wildfires occurred during an extremely dry summer that killed many A. cupressoides stands on the high plateau in the center of Tasmania. That fire year, coupled with subsequent regeneration failure, caused a loss of ca. 10% of the geographic extent of this endemic Tasmanian forest type. To provide historical context for these large-scale fire events, we (i) collected dendroecological, floristic, and structural data, (ii) documented the postfire survival and regeneration of A. cupressoides and co-occurring understory species, and (iii) assessed postfire understory plant community composition and flammability. We found that fire frequency did not vary following the arrival of European settlers, and that A. cupressoides populations were able to persist under a regime of low-to-mid severity fires prior to the 1960 fires. Our data indicate that the 1960 fires were (i) of greater severity than previous fires, (ii) herbivory by native marsupials may limit seedling survival in both burned and unburned A. cupressoides stands, and (iii) the loss of A. cupressoides populations is largely irreversible given the relatively high fuel loads of postfire vegetation communities that are dominated by resprouting shrubs. We suggest that the feedback between regeneration failure and increased flammability will be further exacerbated by a warmer and drier climate causing A. cupressoides to contract to the most fire-proof landscape settings., (© 2014 John Wiley & Sons Ltd.)

Nanomedicine will play an increasing role in prevention and treatment across the entire healthcare spectrum. However, their precise market size, economic value and areas of application remain unclear. This opacity, including the question of what constitutes nanomedicine matters, especially when considered alongside the key regulatory questions and concerns. This article begins by placing these key questions into context in relation to the current scientific state of the art, focusing particular attention on the human health and safety context. In exploring these central questions surrounding the regulation of nanomedicine, this perspective also explores existing and suggested frameworks that aim to deal with emerging technologies more generally. It then outlines priority areas for action and general conclusions specific to nanomedicine.