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1.
During the long eighteenth century, boundaries between theology and natural philosophy, between imaginary and factual travel narratives, between fiction and social commentary, were far more fluid than they are today. To explore these relationships, this paper links Mary Shelley’s Frankenstein—a book often hailed as the first science fiction novel—to two earlier works which are now less well known: Edmond Halley’s article about terrestrial magnetism, in which he suggested that God had created inhabited illuminated cavities inside the earth; and a satirical fantasy voyage written by the Danish author Ludvig Holberg, but published anonymously as Niels Klim’s journey to the underground and immediately translated into many languages. Attention is focussed on how the ambiguous presentation of these and other texts blurs any straightforward classification of genres. The aim of examining these writers together is not to search for direct mappings from one project to another, but instead to introduce Holberg’s unfamiliar yet important book and also to cast new light on Frankenstein, one of England’s most famous works of literature.  相似文献   
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We compare forecasts of recessions using four different specifications of the probit model: a time invariant conditionally independent version; a business cycle specific conditionally independent model; a time invariant probit with autocorrelated errors; and a business cycle specific probit with autocorrelated errors. The more sophisticated versions of the model take into account some of the potential underlying causes of the documented predictive instability of the yield curve. We find strong evidence in favour of the more sophisticated specification, which allows for multiple breakpoints across business cycles and autocorrelation. We also develop a new approach to the construction of real time forecasting of recession probabilities. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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Summary 9 (10 mg/kg, i.p.) administered to mice immediately after withdrawal from a 3-day exposure to ethanol vapor was found to intensify withdrawal reactions. No effect was seen when 9 was administered chronically during the exposure to ethanol.  相似文献   
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Pathogen-mediated changes in host behaviour can result from hosts altering their habitat preferences. Although infection risk with pathogenic fungus Batrachochytrium dendrobatidis in amphibians is associated with environments favouring its growth, the relationship with microhabitat use has not been examined. Here, we aim to determine if microhabitats used by frogs during their nocturnal activity predict B. dendrobatidis prevalence and infection intensity. Our focal host, Eleutherodactylus coqui, is a habitat generalist that uses multiple habitats from the forest floor to the canopy. We analysed data on B. dendrobatidis occurrence in 157 adults and 122 juveniles at El Yunque National forest in Puerto Rico. We categorized each individual’s nocturnal microhabitat as forest floor, curled palm fronds in the floor, arboreal bromeliads and foliage or tree trunks 50 cm to 2.5 m above ground. We found that frogs on the forest floor had the greatest B. dendrobatidis prevalence (73%), compared with those active in vegetation above ground (55%). Overall, the probability of B. dendrobatidis infection in frogs using microhabitats on the forest floor was twice as great as for those on arboreal substrates. Differences in B. dendrobatidis prevalence and intensity in E. coqui may be explained by specific abiotic conditions of microenvironments (temperature and humidity) affecting both pathogen and host, and by the age-specific ecological requirements of hosts. Adults were found to be most active in microhabitats where individuals had lower infection burdens, suggesting pathogen-modulated habitat choice. This work has important implications for the evolutionary dynamics of enzootic diseases and provides data that may inform potential mitigation strategies against a generalist amphibian pathogen.  相似文献   
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How People Use Rich Pictures to Help Them Think and Act   总被引:1,自引:1,他引:0  
Groups of all kinds are complex organisations. To understand them and to facilitate them in process terms is a matter of rich and diverse discourse in varied fields from sustainable development to coastal ecology; from bandwidth in rural communities to health service provision. How to allow groups to discourse, problem solve and review their own issues and concerns? Diagrams in general and rich pictures in particular can be great means to allow groups to explore their subconscious, their occult sentiments and conflicted understandings. This paper explores and explains diverse use of pictures and shows how they can be applied and understood in group processes of all kinds.  相似文献   
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Calorie restriction extends lifespan and produces a metabolic profile desirable for treating diseases of ageing such as type 2 diabetes. SIRT1, an NAD+-dependent deacetylase, is a principal modulator of pathways downstream of calorie restriction that produce beneficial effects on glucose homeostasis and insulin sensitivity. Resveratrol, a polyphenolic SIRT1 activator, mimics the anti-ageing effects of calorie restriction in lower organisms and in mice fed a high-fat diet ameliorates insulin resistance, increases mitochondrial content, and prolongs survival. Here we describe the identification and characterization of small molecule activators of SIRT1 that are structurally unrelated to, and 1,000-fold more potent than, resveratrol. These compounds bind to the SIRT1 enzyme-peptide substrate complex at an allosteric site amino-terminal to the catalytic domain and lower the Michaelis constant for acetylated substrates. In diet-induced obese and genetically obese mice, these compounds improve insulin sensitivity, lower plasma glucose, and increase mitochondrial capacity. In Zucker fa/fa rats, hyperinsulinaemic-euglycaemic clamp studies demonstrate that SIRT1 activators improve whole-body glucose homeostasis and insulin sensitivity in adipose tissue, skeletal muscle and liver. Thus, SIRT1 activation is a promising new therapeutic approach for treating diseases of ageing such as type 2 diabetes.  相似文献   
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