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961.
The use of specimen-label databases for conservation purposes: an example using Mexican Papilionid and Pierid butterflies 总被引:2,自引:0,他引:2
In recent years, use of databases of the labels of specimens deposited in museums and herbaria is becoming increasingly common as a tool for addressing biodiversity conservation and management problems. These databases are often large in size and complex in structure, and their application to conservation deserves a wider appreciation of some of the biases, gaps and potential pitfalls common to them. In this paper, we discuss some of the problems associated with using such databases for obtaining lists of species for arbitrary sites, as well as for the estimation of the distribution area of single species. The possibility of obtaining these closely related variables using specimen databases is shown to be scale-dependent. A tool based on mark-recapture techniques is applied to the problem of: (i) detecting sites with low number of species due to lack of adequate in-site sampling and, (ii) species with small estimated areas due to poor spatial coverage of samples. 相似文献
962.
Maria Valdirene Leite Pedone-Bonfim Danielle Karla Alves da Silva Leonor Costa Maia Adriana Mayumi Yano-Melo 《Symbiosis (Philadelphia, Pa.)》2018,74(2):79-88
In the terrestrial ecosystems, soil is an important component, characterized by holding high diversity of microorganisms which play a key role for productivity and vegetal composition. The group of symbionts microorganisms stands out for contributing directly to the growth and plant nutrition, and among them, the arbuscular mycorrhizal fungi form one of the oldest and well established associations. In order to increase the knowledge and contribute for further research with AMF and plants of Caatinga, in this review we compile data from previous studies on the effects of symbiosis between arbuscular mycorrhizal fungi (AMF) and plants of the Caatinga, a type of dry tropical forest found in the northeast of Brazil. These studies collected data under various experimental conditions, emphasizing fungal efficiency and host responsiveness in soils with varied fertility. From our analysis we conclude that in general the symbiotic efficiency on these plants depends on many factors, such as the plant-fungi combination, fertility and soil type. Furthermore, in leguminosae the impact of a joint inoculation with nitrogen fixing bacteria must be taken into account. Claroideoglomus etunicatum was the most tested AMF species benefiting almost all plants tested. Approximately 30 plant species were studied regarding possible benefits provided by AMF and of these only Hymenea courbaril and Aspidosperma pyrifolium did not respond to mycorrhization. Higher efficiency of the mycorrhizal symbiosis can be obtained in soils with low P levels, emphasizing the essential role of these microorganisms in the growth and survival of plant species from the Caatinga biome. 相似文献
963.
M D Pérez C Díaz de Villegas L Sánchez P Aranda J M Ena M Calvo 《Journal of biochemistry》1989,106(6):1094-1097
beta-Lactoglobulin isolated from milk of cow, sheep, and goat had about 0.5 mol of fatty acids bound per mol of monomer protein. Fatty acids, mainly palmitic and oleic acids, were the major components (about 75% of total lipids). Albumin isolated from the same samples had about 4.5 mol of fatty acids bound per mol of protein. These two proteins were the only whey proteins able to bind labeled fatty acids in vitro. Interaction of beta-lactoglobulin and albumin with insolubilized fatty acids showed some differences, suggesting different structures of the respective fatty acid binding sites. 相似文献
964.
965.
Sofia Duarte Maria Leonor Fidalgo Cláudia Pascoal Fernanda Cássio 《Hydrobiologia》2012,680(1):149-157
In aquatic ecosystems, microorganisms and invertebrates provide critical links between plant detritus and higher trophic levels.
Atyaephyra desmarestii is an omnivorous decapod that inhabits freshwaters and exhibits high tolerance to temperature oscillations and high ability
to colonize new habitats. Although A. desmarestii is able to ingest a variety of foods, few studies have been conducted to elucidate the role of this freshwater shrimp on
detritus breakdown in streams. In this study, A. desmarestii was allowed to feed on conditioned or unconditioned alder and eucalyptus leaves in microcosms with or without access to its
fecal pellets. At the end of the experiment, total body length of the animals was measured, and the remaining leaves and fecal
pellets were used for dry mass quantification and assessment of bacterial and fungal diversity by denaturing gradient gel
electrophoresis (DGGE). Cluster analyses of DGGE fingerprints indicated that the major differences in microbial communities
on leaves were between leaf types, while on fecal pellets were between conditioned and unconditioned leaves. However, the
consumption rate by the shrimp did not differ between leaf types, and was significantly higher on leaves conditioned by microorganisms
and in treatments without access to feces. In treatments without access to feces, the production of feces and fine particulate
organic matter was also significantly higher for conditioned leaves. Overall, our results support the feeding plasticity of
A. desmarestii and its potential role in plant litter breakdown in streams. This might have implications for maintaining stream ecosystem
functioning, particularly if more vulnerable shredders decline. 相似文献
966.
967.
Cesar Rodriguez-Saona Hans T. Alborn Cam Oehlschlager Carolina Calvo Vera Kyryczenko-Roth Sunil Tewari Martha M. Sylvia Anne L. Averill 《Journal of Applied Entomology》2020,144(5):417-421
The cranberry weevil Anthonomus musculus Say is a key pest of highbush blueberries (Vaccinium corymbosum L.) and cranberries (Vaccinium macrocarpon Aiton) in the northeastern United States. Previous studies have reported A. musculus adult attraction to traps baited with the aggregation pheromone of the pepper weevil Anthonomus eugenii Cano, likely because these two weevils share similar pheromone blends that differ only in two components. The A. musculus aggregation pheromone contains (Z)-2-(3,3-dimethylcyclohexylidene) ethanol (Z grandlure II), (Z)-(3,3-dimethylcyclohexylidene) acetaldehyde (grandlure III), (E)-(3,3-dimethylcyclohexylidene) acetaldehyde (grandlure IV) and (E)-3,7-dimethyl-2,6-octadien-1-ol (geraniol); whereas A. eugenii produces a pheromone blend that includes (E)-2-(3,3-dimethylcyclohexylidene) ethanol (E grandlure II) and (E)-3,7-dimethyl-2,6-octadienoic acid (geranic acid) in addition to the four A. musculus pheromone components. Here, we hypothesized that differences in pheromone composition between these two species influence A. musculus adult attraction to its aggregation pheromone. To test this, we studied the response of A. musculus to its pheromone blend with and without E grandlure II and geranic acid, a commercial A. eugenii pheromone lure and a no-lure control in highbush blueberry and cranberry fields in New Jersey and Massachusetts, respectively. Regardless of crop type, A. musculus adults were more attracted to their four-component pheromone blend and the blend plus geranic acid than the commercial A. eugenii pheromone and the no-lure controls. The A. musculus pheromone blend plus E grandlure II and the A. eugenii pheromone blend also captured more A. musculus adults than the no-lure control but not compared to the commercial A. eugenii pheromone. Further analysis showed that A. musculus adults are significantly (~27%) less attracted to their pheromone blend if it contains E grandlure II, although the addition of geranic acid did not affect their response. These findings may help guide future efforts towards the development of behaviour-based tools to monitor and manage A. musculus. 相似文献
968.
969.
970.
Florent Calvo 《Chirality》2015,27(3):253-261
The nonlinear response and dissociation propensity of an isolated chiral molecule, camphor, to a circularly polarized infrared laser pulse was simulated by molecular dynamics as a function of the excitation wavelength. The results indicate similarities with linear absorption spectra, but also differences that are ascribable to dynamical anharmonic effects. Comparing the responses between left‐ and right‐circularly polarized pulses in terms of dissociation probabilities, or equivalently between R‐ and S‐camphor to a similarly polarized pulse, we find significant differences for the fingerprint C = O amide mode, with a sensitivity that could be sufficient to possibly enable vibrational circular dichroism as an action technique for probing molecular chirality and absolute conformations in the gas phase. Chirality 27:253–261, 2015. © 2015 Wiley Periodicals, Inc. 相似文献