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1.
Coral reefs are under increasing pressure from anthropogenic and climate-induced stressors. The ability of reefs to reassemble and regenerate after disturbances (i.e., resilience) is largely dependent on the capacity of herbivores to prevent macroalgal expansion, and the replenishment of coral populations through larval recruitment. Currently there is a paucity of this information for higher latitude, subtropical reefs. To assess the potential resilience of the benthic reef assemblages of Lord Howe Island (31°32'S, 159°04'E), the worlds' southernmost coral reef, we quantified the benthic composition, densities of juvenile corals (as a proxy for coral recruitment), and herbivorous fish communities. Despite some variation among habitats and sites, benthic communities were dominated by live scleractinian corals (mean cover 37.4%) and fleshy macroalgae (20.9%). Live coral cover was higher than in most other subtropical reefs and directly comparable to lower latitude tropical reefs. Juvenile coral densities (0.8 ind.m(-2)), however, were 5-200 times lower than those reported for tropical reefs. Overall, macroalgal cover was negatively related to the cover of live coral and the density of juvenile corals, but displayed no relationship with herbivorous fish biomass. The biomass of herbivorous fishes was relatively low (204 kg.ha(-1)), and in marked contrast to tropical reefs was dominated by macroalgal browsing species (84.1%) with relatively few grazing species. Despite their extremely low biomass, grazing fishes were positively related to both the density of juvenile corals and the cover of bare substrata, suggesting that they may enhance the recruitment of corals through the provision of suitable settlement sites. Although Lord Howe Islands' reefs are currently coral-dominated, the high macroalgal cover, coupled with limited coral recruitment and low coral growth rates suggest these reefs may be extremely susceptible to future disturbances.  相似文献   
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Endemic species are assumed to have a high risk of extinction because their restricted geographic range is often associated with low abundance and high ecological specialization. This study examines the abundance of Chaetodon butterflyfishes at Lord Howe Island in the south‐west Pacific, and compares interspecific differences in local abundance to the feeding behavior and geographic range of these species. Contrary to expected correlations between abundance and geographic range, the single most abundant species of butterflyfish was Chaetodon tricinctus, which is endemic to Lord Howe Island and adjacent reefs; densities of C. tricinctus (14.1 ± 2.1 SE fish per 200m2) were >3 times higher than the next most abundant butterflyfish (Chaetodon melannotus), and even more abundant than many other geographically widespread species. Dietary breadth for the five dominant butterflyfishes at Lord Howe Island was weakly and generally negative correlated with abundance. The endemic C. tricinctus was a distinct outlier in this relationship, though our extensive feeding observations suggest some issues with the measurements of dietary breadth for this species. Field observations revealed that all bites taken on benthic substrates by C. tricinctus were from scleractinian corals, but adults rarely, if ever, took bites from the benthos, suggesting that they may be feeding nocturnally and/or using mid‐water prey, such as plankton. Alternatively, the energetic demands of C. tricinctus may be fundamentally different to other coral‐feeding butterflyfishes. Neither dietary specialization nor geographic range accounts for interspecific variation in abundance of coral reef butterflyfishes at Lord Howe Island, while much more work on the foraging behavior and population dynamics of C. tricinctus will be required to understand its’ abundance at this location.  相似文献   
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Understanding the foraging patterns of reef fishes is crucial for determining patterns of resource use and the sensitivity of species to environmental change. While changes in prey availability and interspecific competition have been linked to patterns of prey selection, body condition, and survival in coral reef fishes, rarely has the influence of abiotic environmental conditions on foraging been considered. We used underwater digital video to explore how prey availability and wave exposure influence the behavioural time budgets and prey selectivity of four species of obligate coral-feeding butterflyfishes. All four species displayed high selectivity towards live hard corals, both in terms of time invested and frequency of searching and feeding events. However, our novel analysis revealed that such selectivity was sensitive to wave exposure in some species, despite there being no significant differences in the availability of each prey category across exposures. In most cases, these obligate corallivores increased their selectivity towards their most favoured prey types at sites of high wave exposure. This suggests there are costs to foraging under different wave environments that can shape the foraging patterns of butterflyfishes in concert with other conditions such as prey availability, interspecific competition, and territoriality. Given that energy acquisition is crucial to the survival and fitness of fishes, we highlight how such environmental forcing of foraging behaviour may influence the ecological response of species to the ubiquitous and highly variable wave climates of shallow coral reefs.  相似文献   
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This paper reports on a workshop conducted in Australia in 2010, entitled ‘Management, Conservation, and Scientific Challenges on Subtropical Reefs under Climate Change’. The workshop brought together 26 experts actively involved in the science and management of subtropical reefs. Its primary aim was to identify the areas of research that need to be most urgently addressed to improve the decision‐making framework for managers of subtropical reefs. The main findings of the workshop were a sustainable subtropical reefs declaration that highlights seven research priorities for subtropical reefs. These are to (i) conduct research and management activities across local government, state and bioregion borders; (ii) understand natural variability of environmental conditions; (iii) quantify socio‐economic factors and ecosystem services; (iv) benchmark cross‐realm connectivity; (v) know marine population connectivity; (vi) habitat mapping and ecological research; and (v) determine refugia. These findings are hoped to form a basis for focussing research efforts, leveraging funds and assisting managers with allocation of resources.  相似文献   
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BACKGROUND: We present a 12-year-old girl with a 5-year history of progressive virilization. RESULTS: Regarding elevated plasma levels of 17-hydroxyprogesterone (17-OHP) and androgens, normal ultrasound and CT scan of ovaries and adrenal glands, the nonclassic form of congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency was presumed the cause of virilization. As the glucocorticoid therapy did not normalize high levels of 17-OHP and androgens, and the DNA analysis did not demonstrate a mutation causing CAH, a laparotomy was performed. Near the right ovary a tumor was found and extirpated. Pathohistological studies determined it to be a rare steroid cell tumor, 'not otherwise specified'. Within the next months the signs of virilization resolved and menarche occurred. CONCLUSIONS: Steroid cell tumor should be considered in differential diagnosis of virilization in childhood. Regarding the age of our patient and pathohistological findings of the tumor, her prognosis is favorable.  相似文献   
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The next 10 years are considered a critical decade for fisheries. Declining fish stocks in combination with mounting climate pressure are likely to lead to significant and adverse socio-ecological impacts, threatening sustainability. Responding to these challenges requires modes of governance that are capable of dealing with the complexity and uncertainty associated with the world’s fisheries and their ecosystems. While a range of governance frameworks exist, the concept of polycentric governance has gained prominence in the environmental sector and is posited as a key principle underpinning the resilience of complex socio-ecological systems. However, the application of polycentric governance to fisheries management has been seldom explored. To examine this prospect, we review the literature on polycentric governance to elucidate its potential value in improving the outlook for fisheries and their associated ecosystems. We highlight a number of unique characteristics that overcome known limitations in other forms of governance—polycentric systems are highly participatory and promote the broadest levels of stakeholder involvement, they increase policy freedom at the local level, and they improve the spatial fit between knowledge, action and socio-ecological contexts to ensure that governance responses are implemented at the most appropriate scale. Through fisheries case-studies, we demonstrate that these characteristics are important in helping fisheries respond to complex challenges. Finally, we articulate key knowledge gaps that should be addressed through future research to understand the conditions under which polycentric governance systems are most suited, and the ways in which they can be operationalised most effectively.  相似文献   
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We studied five patients with SSPE during a 10-year period (1994-2004). The first clinical symptoms developed at the age of 5-11 years. All patients were vaccinated regularly against measles according to the official immunization schedule. One patient had measles at the age of 18 months. Two of them had a history of morbilliform rash (unrecognized measles) at the age of six and seven months, respectively. In two patients, with no history of measles before vaccination the disease started after varicella infection. Using complement-fixation (F) test and EIA, antibodies to measles virus (MV) were detected in the CSF and sera of all patients. The CF-antibody titers ranged from 1:1024 to 1:65536 in sera and from 1:16 to 1:128 in CSF samples. MV antigen was detected in brain imprints using IFA in two patients. Electron microscopic analysis revealed intranuclear viral inclusions (MV nucleocapsids). Using RT-PCR, viral RNA was found in both patients. Nucleotide sequence analysis showed that the viruses found in the brain tissue belonged to the wild-type MV D6 genotype [7].  相似文献   
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Fisheries and marine ecosystems are challenged globally by climate change with subsequent biological and socio-ecological implications. Adaptation represents one pathway by which management agencies can seek to ensure sustainability of these resources for societal well-being, particularly when based on strong scientific evidence. Here, we examined the extent of primary scientific literature that is currently available to inform climate adaption initiatives for Australian fisheries. This is achieved via a systematic literature review for 99 harvested Australian marine species, aimed at identifying primary scientific articles that reported new knowledge of climate-driven biological changes and/or socio-ecological implications. We then assessed the quantity of scientific literature against estimated relative climate sensitivity scores for each species (from a previous study), and investigated factors that may influence relative research effort. We found that two-thirds of species had no peer-reviewed climate-related literature available, and that research effort among Australian fisheries species is most closely related to the number of commercial fish stocks per species, and commercial catch weight. We also found that the south-east and western Australian regions had the most climate-related biological information to support climate adaptation in fisheries management. Nonetheless, although accumulating knowledge of the biological and socio-ecological implications of climate change is important, increasing knowledge alone is insufficient to maintain the productivity and profitability of Australian fisheries in light of projected climate impacts. We suggest that the further use of this knowledge to inform decision-making processes is essential to ensure that climate adaptation options are fully explored, to allow sustainable and productive fisheries.

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Improved public understanding of the ocean and the importance of sustainable ocean use, or ocean literacy, is essential for achieving global commitments to sustainable development by 2030 and beyond. However, growing human populations (particularly in mega-cities), urbanisation and socio-economic disparity threaten opportunities for people to engage and connect directly with ocean environments. Thus, a major challenge in engaging the whole of society in achieving ocean sustainability by 2030 is to develop strategies to improve societal connections to the ocean. The concept of ocean literacy reflects public understanding of the ocean, but is also an indication of connections to, and attitudes and behaviours towards, the ocean. Improving and progressing global ocean literacy has potential to catalyse the behaviour changes necessary for achieving a sustainable future. As part of the Future Seas project (https://futureseas2030.org/), this paper aims to synthesise knowledge and perspectives on ocean literacy from a range of disciplines, including but not exclusive to marine biology, socio-ecology, philosophy, technology, psychology, oceanography and human health. Using examples from the literature, we outline the potential for positive change towards a sustainable future based on knowledge that already exists. We focus on four drivers that can influence and improve ocean literacy and societal connections to the ocean: (1) education, (2) cultural connections, (3) technological developments, and (4) knowledge exchange and science-policy interconnections. We explore how each driver plays a role in improving perceptions of the ocean to engender more widespread societal support for effective ocean management and conservation. In doing so, we develop an ocean literacy toolkit, a practical resource for enhancing ocean connections across a broad range of contexts worldwide.

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