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1.
Carlo L. Seifert Martin Volf Leonardo R. Jorge Tomokazu Abe Grace Carscallen Pavel Drozd Rajesh Kumar Greg P.A. Lamarre Martin Libra Maria E. Losada Scott E. Miller Masashi Murakami Geoffrey Nichols Petr Pyszko Martin igut David L. Wagner Vojtch Novotný 《Ecology and evolution》2020,10(24):14137
- Assemblages of insect herbivores are structured by plant traits such as nutrient content, secondary metabolites, physical traits, and phenology. Many of these traits are phylogenetically conserved, implying a decrease in trait similarity with increasing phylogenetic distance of the host plant taxa. Thus, a metric of phylogenetic distances and relationships can be considered a proxy for phylogenetically conserved plant traits and used to predict variation in herbivorous insect assemblages among co‐occurring plant species.
- Using a Holarctic dataset of exposed‐feeding and shelter‐building caterpillars, we aimed at showing how phylogenetic relationships among host plants explain compositional changes and characteristics of herbivore assemblages.
- Our plant–caterpillar network data derived from plot‐based samplings at three different continents included >28,000 individual caterpillar–plant interactions. We tested whether increasing phylogenetic distance of the host plants leads to a decrease in caterpillar assemblage overlap. We further investigated to what degree phylogenetic isolation of a host tree species within the local community explains abundance, density, richness, and mean specialization of its associated caterpillar assemblage.
- The overlap of caterpillar assemblages decreased with increasing phylogenetic distance among the host tree species. Phylogenetic isolation of a host plant within the local plant community was correlated with lower richness and mean specialization of the associated caterpillar assemblages. Phylogenetic isolation had no effect on caterpillar abundance or density. The effects of plant phylogeny were consistent across exposed‐feeding and shelter‐building caterpillars.
- Our study reveals that distance metrics obtained from host plant phylogeny are useful predictors to explain compositional turnover among hosts and host‐specific variations in richness and mean specialization of associated insect herbivore assemblages in temperate broadleaf forests. As phylogenetic information of plant communities is becoming increasingly available, further large‐scale studies are needed to investigate to what degree plant phylogeny structures herbivore assemblages in other biomes and ecosystems.
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K P Zimmer J Caselitz G Seifert 《Virchows Archiv. B, Cell pathology including molecular pathology》1985,49(2):161-173
Epithelial cells from various sites and at various stages of differentiation reveal distinct cytokeratin polypeptide patterns. WE have localized these heterogeneous elements at the subcellular level in human salivary glands and in a solid tumor of the breast using a monoclonal and a polyclonal antibody against cytokeratin, and an antibody against tissue polypeptide antigen (TPA) which seems to be related to some cytokeratins. Labeling by the cytokeratin antibodies was more intense in squamous and duct cells than in acinar cells. The TPA:B1 antibody reacted predominantly with duct cells and to a lesser extent with acinar and squamous cells. A precise evaluation of the labeling pattern and a well-preserved cell structure appeared to be important factors in obtaining more detailed information about intermediate filament proteins. The cryoultramicrotomy and the protein A-gold technique are suitable for these studies. 相似文献
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The main energy reserves in brown trout, Salmo trutta and Arctic char, Salvelinus alpinus are located in the abdominal cavity and the musculature. The energy content of the rest of the intestines after removal of the gonads, swim bladder, and liver is a good parameter to assess the gross nutritional state of Arctic char and brown trout. This method is laborious, but analysing the dry matter fraction (or the water content) of the same organs instead of their energy content is a practical alternative. The dry matter fraction of these organs expressed as a percentage of its wet weight is here called the 'Gut index'. 相似文献
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The cyclic pyrimidine nucleotide, cCMP, is an endogenous substance in mammalian cells but little is known on its functional role. We studied the effects of cCMP, its cell-permeant analogue, N4,2'-O-dibutyryl cytidine 3':5'-cyclic monophosphate (Bt2cCMP), and of butyrate on superoxide (O2-) formation and cytosolic Ca2+ [( Ca2+]i) in human neutrophils. Bt2cCMP inhibited O2- formation and the rise in [Ca2+]i induced by a chemotactic peptide at submaximally effective concentrations. O2- formation induced by platelet-activating factor was potentiated by Bt2cCMP, whereas the cyclic nucleotide had no effect on the rise in [Ca2+]i induced by this agonist. Bt2cCMP enhanced O2- formation induced by tau-hexachlorocyclohexane at a submaximally effective concentration. O2- formation stimulated by complement C5a, concanavalin A, NaF, A 23187, phorbol myristate acetate and arachidonic acid was not affected by Bt2cCMP. cCMP was less effective than Bt2cCMP to inhibit fMet-Leu-Phe-induced O2- formation, and butyrate was without effect on any of the functional parameters studied. Our data show that a cell-permeant analogue of cCMP differentially inhibits and potentiates activation of human neutrophils. 相似文献
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Present and future needs for algae and algal products 总被引:1,自引:0,他引:1
A review of the present needs, mainly for production of phycocolloids and food condiments, is given. Supply and demand vary from balanced, in some, to disproportionate in other fields. World-wide shortage of agarophytes contrasts with huge, unexploited beds of brown seaweeds.In future, partly conflicting trends will decide the needs for algae and algal products. Growth in the human population, pollution, overexploitation of land and lack of freshwater will encourage use of seaweeds. Modern biotechnology will favour this development, but will also be a serious threat to industrial exploitation of seaweeds. Future uses of marine algae will be decisively influenced by the effort put into and the results coming out of seaweed research. 相似文献
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We review the New Caledonian representatives of the Australasian endemic hydroptiline genus Acritoptila, based on examination of a considerable collection of material in the Swedish Museum of Natural History and of types of previously established species. A key for identification of males is given and includes 3 species newly described here: A. parallela
sp. n., A. forficata
sp. n. and A. macrospina
sp. n. For all New Caledonian species, male genitalia are illustrated, and for 5 associated females, distinctive features are illustrated and described. 相似文献
10.
- Several animal species are known to distinguish between their own eggs and eggs of unrelated conspecifics. However, the cues involved in this discrimination are often unknown. These cues were studied using the predatory mite Gynaeseius liturivorus Ehara.
- Adult females of these predatory mites oviposit in clusters and avoid oviposition close to eggs laid by other females, resulting in reduced cannibalism between offspring. Because predatory mites are blind, it was tested whether volatiles of eggs were used as a cue for egg recognition.
- Adult female predatory mites were offered volatile cues of their own eggs and of unrelated conspecific eggs, and females were prevented from contacting the eggs. Predatory mites oviposited closer to their own eggs than to unrelated eggs. This preference was observed even when one own and one unrelated egg were offered as a volatile source.
- These results suggest that adult female predatory mites can determine kinship using volatiles released from the eggs.