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51.
Summary

A history of ecological studies in mycology developed around the trophic state of the fungi is taken from the rich heritage of information available. With the renewed interest in biodiversity and the array of molecular and complementary techniques available the future could be very rewarding.  相似文献   
52.
A tripartite receptor comprising the external region of the erythropoietin (Epo) receptor, the transmembrane and JAK-binding domains of the gp130 subunit of the interleukin-6 (IL-6) receptor, and a seven amino acid STAT1 recruitment motif (Y440) from the interferon (IFN)-gamma receptor, efficiently mediates an IFN-gamma-like response. An analogous completely foreign chimeric receptor in which the Y440 motif is replaced with the Y905 motif from gp130 also mediates an IFN-gamma-like response, but less efficiently. The IFNGR1 signal-transducing subunit of the IFN-gamma receptor is tyrosine phosphorylated through the chimeric receptors and the endogenous IL-6 and OSM receptors. Cross phosphorylation of IFNGR1 is not, however, required for the IFN-gamma-like response through the chimeric receptors, nor does it mediate an IFN-gamma-like response to IL-6 or OSM. The data argue strongly for modular JAK/STAT signalling and against any rigid structural organization for the "pathways" involved. They emphasize the likely high degree of overlap between the signals generated from disparate JAK-receptor complexes and show that relatively minor changes in such complexes can profoundly affect the response.  相似文献   
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Ongoing greenhouse gas emissions can modify climate processes and induce shifts in ocean temperature, pH, oxygen concentration, and productivity, which in turn could alter biological and social systems. Here, we provide a synoptic global assessment of the simultaneous changes in future ocean biogeochemical variables over marine biota and their broader implications for people. We analyzed modern Earth System Models forced by greenhouse gas concentration pathways until 2100 and showed that the entire world''s ocean surface will be simultaneously impacted by varying intensities of ocean warming, acidification, oxygen depletion, or shortfalls in productivity. In contrast, only a small fraction of the world''s ocean surface, mostly in polar regions, will experience increased oxygenation and productivity, while almost nowhere will there be ocean cooling or pH elevation. We compiled the global distribution of 32 marine habitats and biodiversity hotspots and found that they would all experience simultaneous exposure to changes in multiple biogeochemical variables. This superposition highlights the high risk for synergistic ecosystem responses, the suite of physiological adaptations needed to cope with future climate change, and the potential for reorganization of global biodiversity patterns. If co-occurring biogeochemical changes influence the delivery of ocean goods and services, then they could also have a considerable effect on human welfare. Approximately 470 to 870 million of the poorest people in the world rely heavily on the ocean for food, jobs, and revenues and live in countries that will be most affected by simultaneous changes in ocean biogeochemistry. These results highlight the high risk of degradation of marine ecosystems and associated human hardship expected in a future following current trends in anthropogenic greenhouse gas emissions.  相似文献   
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Aim Connectivity is a key determinant of the distribution and abundance of organisms and is greatly influenced by anthropogenic landscape modification, yet we lack a synthetic perspective on the magnitude and extent of matrix effects on connectivity. We synthesize results from published studies to understand the importance of matrix effects on fragmented animal populations. Location Global. Methods We conduct a meta‐analysis of 283 fragmented populations representing 184 terrestrial animal taxa to determine the strength of matrix composition effects on the occurrence and abundance of animals in fragmented habitat. Results Studies that use data on matrix composition report greater effects on abundance and occupancy of fragmented populations than studies that define connectivity without regard to the surrounding matrix (i.e. ‘binary’ studies that describe only characteristics of patch habitat). Main conclusions Our findings underscore that conservation strategies must consider the importance of matrix habitat, have important implications for metapopulation and metacommunity paradigms, and provide direct large‐scale, multi‐taxa evidence that matrix habitat is an important driver of ecological dynamics in heterogeneous landscapes.  相似文献   
58.
Summary

540 agarics and 156 other basidiomycetes, (excluding rusts and smuts), are recorded for an area within a 40 km radius of the Kindrogan Field Centre, Perthshire. Several are new records and do not appear in checklists for the British Isles; notes are provided on new, interesting and rare species.  相似文献   
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Addendum     
Summary

A survey of South Craigroston Wood shows a range of tree densities from ?200 to? 1000 trees/ha with dominant oak and birch but with an increased representation of alder in wetter areas. The size distribution of oaks may be tentatively related to previous management. The ground flora can be divided into a major grouping associated with drier, acidic sites with a high incidence of oak and minor, species-rich, groupings associated with damper and more base-rich sites with greater proportions of alder, ash and hazel. The ground flora is much less diverse than that described from the island of Inchcailloch.  相似文献   
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Cumaceans are a diverse order of small, benthic marine crustaceans. Phylogenetic hypotheses for the eight currently recognized cumacean families have not been formally proposed. However, based on external morphological traits and Linnean classification, a few conflicting hypotheses of relatedness have been proposed. Family definitions rely on morphological characters that often overlap and diagnoses are based on a combination of non-unique characters. Morphological analysis does not provide a well-resolved phylogeny. In the present study, we use amino acid sequences from the mitochondrial cytochrome oxidase I gene to produce a molecular phylogenetic hypothesis for the families of Cumacea. Phylogenetic analyses at the amino acid level were performed under Bayesian, likelihood, and parsimony methods. Results strongly suggest that families lacking an articulated telson form a monophyletic group. This pleotelson clade, composed of the families Bodotriidae, Leuconidae, and Nannastacidae, is the most derived within the Cumacea. Within this group, the Bodotriidae resolve paraphyletically, with Leuconidae and Nannastacidae embedded within it. Comparison of the molecular phylogeny with that based on morphology suggests that many "diagnostic" characters are homoplasious.  相似文献   
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