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Di Jin  Porter Hoagland   《Harmful algae》2008,7(6):772-781
In this study, we develop a framework for measuring the value of harmful algal bloom (HAB) predictions. The framework captures the effects of both private and public responses to HABs. Using data from the New England nearshore commercial shellfish fishery and impact estimates for a large-scale HAB event in 2005, we illustrate how the potential value of HAB forecasts may be estimated. The results of our study suggest that the long-term value of a HAB prediction and tracking system for the Gulf of Maine is sensitive to the frequency of HAB events, the accuracy of predictions, the choice of HAB impact measures, and the effectiveness of public and private responses.  相似文献   
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This study evaluated whether showing a video of the different ways of raising goats for milk affected consumer acceptability. Four combinations, 2 Videos (intensive [INT] and semiextensive [SEM] system) × 2 Milk Types (semiskimmed [S] and whole [W] milk), were evaluated by 70 habitual consumers of goat milk, who scored their liking and purchase intention during blind (B), expected (E), and informed (I) acceptability sessions. In the B session, consumers tasted both milk types without information. S samples were preferred over W samples. In the E session, SEM video created high expectations in terms of milk liking and purchase intent, whereas the opposite happened when showing INT video. In the I session, consumers showed a clear preference for combinations created using SEM video, regardless of milk type. W-SEM and S-INT were worse (negative disconfirmation) and better (positive disconfirmation) than expected, respectively. A complete assimilation toward expectations occurred only for S-INT. INT video adversely affected the acceptability of S samples. Concerning purchase intent, W-SEM and S-SEM were worse than expected, but the assimilation was complete only for S-SEM: SEM video increased purchase intent for S samples.  相似文献   
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The work of prominent Russian biologist Alexander Gavrilovich Gurwitsch (1874–1954) on the theory of organism development are reviewed. Alexander Gurwitsch introduced the concept of embryonic (morphogenetic, biological, and cellular) field and proposed several revisions of it from 1912 to 1944. Although neither of them can be considered as a final theory of development, his the persistent search for the invariant law that allows the shape (spatial structure) to be proposed for each next developmental stage from the previous shape is of imperishable methodological interest. Alexander Gurwitsch anticipated many ideas of the future theory of self-organization. His theoretical constructions are explicit and experiment-oriented but absolutely not esoteric. They represent a highly important and original contribution to theoretical biology and are an essential step to further development of the ontogenetic theory.  相似文献   
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1. The composition of freshwater invertebrate assemblages at a location is determined by a range of physico‐chemical and biotic factors in the local environment, as well as larger‐scale spatial factors such as sources of recruits. We assessed the relative importance of the species composition of local neighbourhoods and proximal environmental factors on the composition of invertebrate assemblages. 2. Macroinvertebrate assemblages were sampled at 188 running‐water sites in the catchment of the River Rede, north‐east England. A total of 176 species were recorded. 3. Environmental data, in the form of 13 biotic and abiotic measurements that described stream physical structure, aquatic vegetation and water characteristics, were recorded for each site. Detrended correspondence analysis was then used to simplify nine of these stream environmental variables to create an index of stream structure. 4. The species composition of the invertebrate assemblages was related to the environmental variables, using an information theoretic approach. The impact of the species composition of neighbouring sites on each site was determined using Moran's I and autoregressive modelling techniques. 5. Species composition was primarily associated with water pH and stream structure. The importance of the species composition of neighbouring sites in determining local species assemblages differed markedly between taxa. The autoregressive component was low for Coleoptera, intermediate for Trichoptera and Plecoptera, and high for Ephemeroptera. 6. We hypothesise that the observed differences in the autoregressive component amongst these orders reflects variation in their dispersal abilities from neighbouring sites.  相似文献   
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There is ongoing controversy as to whether the genome is a representing system (Sterelny K., Smith K.C. and Dickson M. 1996. Biol. Philos. 11: 377–403; Griffiths P.E. 2001. Philos. Sci. 68: 394–412). Although it is widely recognised that DNA carries information, both correlating with and coding for various outcomes, neither of these implies that the genome has semantic properties like correctness or satisfaction conditions (Godfrey-Smith P. 2002. In: Wolenski J. and Kajania-Placek K. (eds), In the Scope of Logic, Methodology, and the Philosophy of Sciences, Vol. II. Kluwer, Dordrecht, pp. 387–400). Here a modified version of teleosemantics is applied to the genome to show that it does indeed have semantic properties – there is representation in the genome. The account differs in three respects from previous attempts to apply teleosemantics to genes. It emphasises the role of the consumer of representations (in addition to their mode of production). It rejects the standard assumption that genetic representation can be used to explain the course of an organism’s development. And it identifies the explanatory role played by representational properties of the genome. A striking consequence of this account is that other inheritance systems could also be representational. Thus, a version of the parity thesis is accepted (Griffiths P.E. 2001. Philos. Sci. 68: 394–412). However, the criteria for being an inheritance system are demanding, so semantic properties are not ubiquitous.  相似文献   
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The need for information services in medical mycology is discussed. The information service provided by the Review of Medical and Veterinary Mycology is described and compared with other information services.  相似文献   
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When pasture land is abandoned, there are, in many cases, inhibitory factors that slow the rate of transition to a natural vegetation. Accordingly, the planned management of restoration has become an important issue in various parts of the world, where environmental conditions can vary widely. Although tree plantations are widely used as a management tool for restoration, there have been few studies addressing the practical aspects of the procedure. I examined effects of tree plantations within the framework of an evaluation of methods for restoring abandoned pasture on Hokkaido, northern Japan. I developed and analyzed vegetation maps spanning the past 57 years for the old-growth site influenced by artificial disturbance; the procedure revealed the pattern of change in the vegetation cover. Matrix model analysis showed that intensive use of plantations contributed to reduction of the area occupied by dwarf bamboo and pasture land (i.e., superior to simple abandonment). Furthermore, the field study of vegetation types and changes in species composition over 20 years suggests that plantations have contributed to a reduction in the effects of factors that inhibit revegetation. However, the establishment of monoculture plantations is frequently viewed skeptically as a procedure that is applied without fundamental ecological knowledge. For sustained management, adequate historical and ecological information on the restoration site should be provided to all stakeholders. An erratum to this article can be found at  相似文献   
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