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131.
Bait traps are effective and commonly used method in the studies of orchid bees. Important questions in the context of this method, including those related to bait dispersion, how long baits remain attractive, the distance from which males are supposed to be attracted to lures and so on, are still open subjects. Data on the attractiveness of bait traps that have remained in the field during two weeks in a large Atlantic forest preserve are presented. Four main results emerge from the data: (i) the abundance of specimens collected per day decreased in all the attractants as the traps were left on the field; (ii) despite this decrease, the absolute number of individuals collected after eight and fifteen days is remarkably, mostly in eugenol and vanillin baits; (iii) the vast majority of species, 22 of 25, was already collected on the first sample day; (iv) a consistent variation in the relative abundance of individuals collected in each scent as collections were made. We urge that bait traps should not be left in the field beyond what is strictly necessary since there is a real possibility of collecting a significant number of individuals as these traps remain available.  相似文献   
132.
While recent imaging techniques provide insights into biological processes from the molecular to the cellular scale, phenotypes at larger scales remain poorly amenable to quantitative analyses. For example, investigations of the biophysical mechanisms generating skin morphological complexity and diversity would greatly benefit from 3D geometry and colour-texture reconstructions. Here, we report on R2OBBIE-3D, an integrated system that combines a robotic arm, a high-resolution digital colour camera, an illumination basket of high-intensity light-emitting diodes and state-of-the-art 3D-reconstruction approaches. We demonstrate that R2OBBIE generates accurate 3D models of biological objects between 1 and 100 cm, makes multiview photometric stereo scanning possible in practical processing times, and enables the capture of colour-texture and geometric resolutions better than 15 μm without the use of magnifying lenses. R2OBBIE has the potential to greatly improve quantitative analyses of phenotypes in addition to providing multiple new applications in, e.g., biomedical science.  相似文献   
133.
134.
In halt: 1. Einleitung und Aufgabenstellung.—2. Art und Ausmaß der Scnäden im Feld-versuch.—3. Wirkungen des Krankheitserregers auf Sommergetreide.—4. Bekämpfungsmöglichkeiten.—5. Besprechung der Ergebnisse.—Zusammenfassung.—Summary. —Literaturverzeichnis.  相似文献   
135.
Carbon-13 relaxation data are reported for exocyclic groups of hexopyranosyl sugar residues in the repeating unit within the Escherichia coli O91 O-antigen polysaccharide in a dilute D2O solution. The measurements of T 1, T 2 and heteronuclear nuclear Overhauser enhancements were carried out at 310 K at two magnetic fields (16.4 T, 21.1 T). The data were analyzed using the standard and extended Lipari–Szabo models, as well as a conformational jump model. The extended version of the Lipari–Szabo and the two-site jump models were most successful for the hydroxymethyl groups of Gal and GlcNAc sugar residues. Different dynamics was found for the hydroxymethyl groups associated with different configurations (d-gluco, d-galacto) of the sugar residues, the latter being faster than the former.  相似文献   
136.
Anthonomus grandis, the cotton boll weevil, causes severe cotton crop losses in North and South America. Here we demonstrate the presence of starch in the cotton pollen grains and young ovules that are the main A. grandis food source. We further demonstrate the presence of α-amylase activity, an essential enzyme of carbohydrate metabolism for many crop pests, in A. grandis midgut. Two α-amylase cDNAs from A. grandis larvae were isolated using RT-PCR followed by 5′ and 3′ RACE techniques. These encode proteins with predicted molecular masses of 50.8 and 52.7 kDa, respectively, which share 58% amino acid identity. Expression of both genes is induced upon feeding and concentrated in the midgut of adult insects. Several α-amylase inhibitors from plants were assayed against A. grandis α-amylases but, unexpectedly, only the BIII inhibitor from rye kernels proved highly effective, with inhibitors generally active against other insect amylases lacking effect. Structural modeling of Amylag1 and Amylag2 showed that different factors seem to be responsible for the lack of effect of 0.19 and α-AI1 inhibitors on A. grandis α-amylase activity. This work suggests that genetic engineering of cotton to express α-amylase inhibitors may offer a novel route to A. grandis resistance.  相似文献   
137.
Interaction computing (IC) aims to map the properties of integrable low-dimensional non-linear dynamical systems to the discrete domain of finite-state automata in an attempt to reproduce in software the self-organizing and dynamically stable properties of sub-cellular biochemical systems. As the work reported in this paper is still at the early stages of theory development it focuses on the analysis of a particularly simple chemical oscillator, the Belousov–Zhabotinsky (BZ) reaction. After retracing the rationale for IC developed over the past several years from the physical, biological, mathematical, and computer science points of view, the paper presents an elementary discussion of the Krohn–Rhodes decomposition of finite-state automata, including the holonomy decomposition of a simple automaton, and of its interpretation as an abstract positional number system. The method is then applied to the analysis of the algebraic properties of discrete finite-state automata derived from a simplified Petri net model of the BZ reaction. In the simplest possible and symmetrical case the corresponding automaton is, not surprisingly, found to contain exclusively cyclic groups. In a second, asymmetrical case, the decomposition is much more complex and includes five different simple non-abelian groups whose potential relevance arises from their ability to encode functionally complete algebras. The possible computational relevance of these findings is discussed and possible conclusions are drawn.  相似文献   
138.
The International Journal of Life Cycle Assessment - Environmental product declarations (EPDs) are standardized tools based on life cycle assessment (LCA) to communicate and compare environmental...  相似文献   
139.
Extremophiles - The prokaryotic communities of water bodies contaminated by acid mine drainage from the São Domingos mining area in southern Portugal were analyzed using a meta-taxonomics...  相似文献   
140.
In this work we have studied the intracellular localization properties of the Gag and Env proteins of Moloney murine leukemia virus (MLV) and human immunodeficiency virus (HIV) in dorsal root ganglion (DRG) neurons of rat. These neurons form thick bundles of axons, which facilitates protein localization studies by immunofluorescence analyses. When such neuron cultures were infected with recombinant Semliki Forest virus particles carrying the gag genes of either retrovirus, the expressed Gag proteins were localized to both the somatic and the axonal regions of the DRG neurons. In contrast, the Env proteins were confined only to the somatic region. When the Gag and Env proteins were coexpressed, the Gag proteins were also excluded from the axons. This effect of the Env proteins was shown to be dependent on the concentration of the Gag proteins in the neuron and also to be specific for homologous pairs of retrovirus proteins. Therefore, the results suggest that there are specific interactions between the Env and the Gag proteins of MLV and HIV in the DRG neurons.  相似文献   
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