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31.
Abstract: Research on the economic performance of small states has concentrated on the implications of small size and thin local markets. An interesting feature of many of the world's smallest states, of which the Pacific region has many, is that they face additional challenges than just small size. Many are remote from global markets for their products. In addition, a large number are also islands, many of which are also mountainous. Many of the smaller states are not just islands, but are also archipelagos. Hence in addition to small size, many of the world's small states also exhibit four other characteristics that may affect their economic performance: insularity, remoteness, being archipelagos and being highly mountainous entities. This paper examines the nature of the challenges posed by these four characteristics and seeks to produce empirical evidence of how difficult it has been to overcome these challenges. The paper draws on empirical evidence for 126 very small global states, dependent territories and highly autonomous regions. The paper then turns to the position of the Pacific small states and dependent territories.  相似文献   
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Trees adapted to mesic and xeric habits may differ in a suite of physiological responses that affect leaf-level carbon balance, including the relationship between photosynthesis (A) and respiration at night (R(n)). Understanding the factors that regulate physiological function in mesic and xeric species is critical for predicting changes in growth and distribution under changing climates. In this study, we examined the relationship between A and R(n), and leaf traits that may regulate A and R(n), in six Eucalyptus species native to mesic or xeric ecosystems, during two 24-h cycles in a common garden under high soil moisture. Peak A and R(n) generally were higher in xeric compared with mesic species. Across species, A and R(n) covaried, correlated with leaf mass per area, leaf N per unit area and daytime soluble sugar accumulation. A also covaried with g(s), which accounted for 93% of the variation in A within species. These results suggest that A and R(n) in these six Eucalyptus species were linked through leaf N and carbohydrates. Further, the relationship between A and R(n) across species suggests that differences in this relationship between mesic and xeric Eucalyptus species in their native habitats may be largely driven by environmental factors rather than inter-specific genetic variation.  相似文献   
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Read AF  Taylor LH 《Science (New York, N.Y.)》2001,292(5519):1099-1102
Microparasite infections often consist of genetically distinct clonal lineages. Ecological interactions between these lineages within hosts can influence disease severity, epidemiology, and evolution. Many medical and veterinary interventions have an impact on genetic diversity within infections, but there is little understanding of the long-term consequences of such interventions for public and animal health. Indeed, much of the theory in this area is based on assumptions contradicted by the available data.  相似文献   
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Stratospheric temperatures on Saturn imply a strong decay of the equatorial winds with altitude. If the decrease in winds reported from recent Hubble Space Telescope images is not a temporal change, then the features tracked must have been at least 130 kilometers higher than in earlier studies. Saturn's south polar stratosphere is warmer than predicted from simple radiative models. The C/H ratio on Saturn is seven times solar, twice Jupiter's. Saturn's ring temperatures have radial variations down to the smallest scale resolved (100 kilometers). Diurnal surface temperature variations on Phoebe suggest a more porous regolith than on the jovian satellites.  相似文献   
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The inflammatory toxicity of lipopolysaccharide (LPS), a component of bacterial cell walls, is driven by the adaptor proteins myeloid differentiation factor 88 (MyD88) and Toll-interleukin 1 receptor domain-containing adapter inducing interferon-beta (TRIF), which together mediate signaling by the endotoxin receptor Toll-like receptor 4 (TLR4). Monophosphoryl lipid A (MPLA) is a low-toxicity derivative of LPS with useful immunostimulatory properties, which is nearing regulatory approval for use as a human vaccine adjuvant. We report here that, in mice, the low toxicity of MPLA's adjuvant function is associated with a bias toward TRIF signaling, which we suggest is likely caused by the active suppression, rather than passive loss, of proinflammatory activity of this LPS derivative. This finding may have important implications for the development of future vaccine adjuvants.  相似文献   
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