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111.
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We analyze 3D flight paths of bumblebees searching for nectar in a laboratory experiment with and without predation risk from artificial spiders. For the flight velocities we find mixed probability distributions reflecting the access to the food sources while the threat posed by the spiders shows up only in the velocity correlations. The bumblebees thus adjust their flight patterns spatially to the environment and temporally to predation risk. Key information on response to environmental changes is contained in temporal correlation functions, as we explain by a simple emergent model. 相似文献
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Robson Araújo de Freitas Junior Paloma Kênia de Moraes Berenguel Lossavaro Cndida Aparecida Leite Kassuya Edgar Julian Paredes-Gamero Nelson Carvalho Farias Júnior Maria Inês Lenz Souza Francielli Maria de Souza Silva-Comar Roberto Kenji Nakamura Cuman Denise Brentan Silva Mnica Cristina Toffoli-Kadri Saulo Euclides Silva-Filho 《Molecules (Basel, Switzerland)》2022,27(12)
The aim of this study is to evaluate the phytochemical profile, oral acute toxicity, and the effect of ylang-ylang (Cananga odorata Hook. F. & Thomson) essential oil (YEO) on acute inflammation. YEO was analyzed by gas chromatography/mass spectrometry. For in vitro tests, YEO was assessed using cytotoxicity, neutrophil chemotaxis induced by N-formyl methionyl leucyl phenylalanine (fMLP), and phagocytic activity tests. YEO was orally administered in zymosan-induced peritonitis, carrageenan-induced leukocyte rolling, and adhesion events in the in situ microcirculation model and in carrageenan-induced paw edema models. YEO (2000 mg/kg) was also tested using an acute toxicity test in Swiss mice. YEO showed a predominance of benzyl acetate, linalool, benzyl benzoate, and methyl benzoate. YEO did not present in vitro cytotoxicity. YEO reduced the in vitro neutrophil chemotaxis induced by fMLP and reduced the phagocytic activity. The oral treatment with YEO reduced the leukocyte recruitment and nitric oxide production in the zymosan-induced peritonitis model, reduced rolling and adherent leukocyte number induced by carrageenan in the in situ microcirculation model, and reduced carrageenan-induced edema and mechanical hyperalgesia. YEO did not present signs of toxicity in the acute toxicity test. In conclusion, YEO affected the leukocyte activation, and presented antiedematogenic, anti-hyperalgesic, and anti-inflammatory properties. 相似文献
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W. Lenz 《Fresenius' Journal of Analytical Chemistry》1907,46(9):557-565
Ohne Zusammenfassung(Mitteilung aus dem pharmazeut. Institute der Universität Berlin.) 相似文献
117.
We consider discrete one-dimensional Schrödinger operators with quasi-Sturmian potentials. We present a new approach to the trace map dynamical system which is independent of the initial conditions and establish a characterization of the spectrum in terms of bounded trace map orbits. Using this, it is shown that the operators have purely singular continuous spectrum and their spectrum is a Cantor set of Lebesgue measure zero. We also exhibit a subclass having purely α-continuous spectrum. All these results hold uniformly on the hull generated by a given potential. 相似文献
118.
Zeitschrift für Physik A Hadrons and nuclei - We study multiple scattering off nuclei in the closure approximation. Instead of reducing the dynamics to one particle potential scattering, the... 相似文献
119.
A generalized, statistical model for calculating the mass spectral fragmentation patterns of deuterated hydrocarbons of low molecular weight is presented. Isotopic differences in bond energies and probabilities of the bond breakage of hydrogen and deuterium are included. Only a single fitting parameter is used. This parameter seems to be consistent for similar species of hydrocarbons. Small statistical deviations from observed spectra for deuterated methanes, acetylenes, ethylenes, and ethanes are obtained when this model is used. 相似文献
120.