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Adachi, R., Osada, H., & Shingai, R. (2008). Phase-dependent preference of thermosensation and chemosensation during simultaneous presentation assay in Caenorhabditis elegans. BMC Neurosci, 9, 106.
Abstract: BACKGROUND: Multi-sensory integration is necessary for organisms to discriminate different environmental stimuli and thus determine behavior. Caenorhabditis elegans has 12 pairs of amphid sensory neurons, which are involved in generating behaviors such as thermotaxis toward cultivation temperature, and chemotaxis toward chemical stimuli. This arrangement of known sensory neurons and measurable behavioral output makes C. elegans suitable for addressing questions of multi-sensory integration in the nervous system. Previous studies have suggested that C. elegans can process different chemoattractants simultaneously. However, little is known about how these organisms can integrate information from stimuli of different modality, such as thermal and chemical stimuli. RESULTS: We studied the behavior of a population of C. elegans during simultaneous presentation of thermal and chemical stimuli. First, we examined thermotaxis within the radial temperature gradient produced by a feedback-controlled thermoregulator. Separately, we examined chemotaxis toward sodium chloride or isoamyl alcohol. Then, assays for simultaneous presentations of 15 degrees C (colder temperature than 20 degrees C room temperature) and chemoattractant were performed with 15 degrees C-cultivated wild-type worms. Unlike the sum of behavioral indices for each separate behavior, simultaneous presentation resulted in a biased migration to cold regions in the first 10 min of the assay, and sodium chloride-regions in the last 40 min. However, when sodium chloride was replaced with isoamyl alcohol in the simultaneous presentation, the behavioral index was very similar to the sum of separate single presentation indices. We then recorded tracks of single worms and analyzed their behavior. For behavior toward sodium chloride, frequencies of forward and backward movements in simultaneous presentation were significantly different from those in single presentation. Also, migration toward 15 degrees C in simultaneous presentation was faster than that in 15 degrees C-single presentation. CONCLUSION: We conclude that worms preferred temperature to chemoattractant at first, but preferred the chemoattractant sodium chloride thereafter. This preference was not seen for isoamyl alcohol presentation. We attribute this phase-dependent preference to the result of integration of thermosensory and chemosensory signals received by distinct sensory neurons.
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Ghars, M. A., Parre, E., Debez, A., Bordenave, M., Richard, L., Leport, L., et al. (2008). Comparative salt tolerance analysis between Arabidopsis thaliana and Thellungiella halophila, with special emphasis on K(+)/Na(+) selectivity and proline accumulation. J Plant Physiol, 165(6), 588–599.
Abstract: The eco-physiology of salt tolerance, with an emphasis on K(+) nutrition and proline accumulation, was investigated in the halophyte Thellungiella halophila and in both wild type and eskimo-1 mutant of the glycophyte Arabidopsis thaliana, which differ in their proline accumulation capacity. Plants cultivated in inert sand were challenged for 3 weeks with up to 500mM NaCl. Low salinity significantly decreased A. thaliana growth, whereas growth restriction was significant only at salt concentrations equal to or exceeding 300mM NaCl in T. halophila. Na(+) content generally increased with the amount of salt added in the culture medium in both species, but T. halophila showed an ability to control Na(+) accumulation in shoots. The analysis of the relationship between water and Na(+) contents suggested an apoplastic sodium accumulation in both species; this trait was more pronounced in A. thaliana than in T. halophila. The better NaCl tolerance in the latter was associated with a better K(+) supply, resulting in higher K(+)/Na(+) ratios. It was also noteworthy that, despite highly accumulating proline, the A. thaliana eskimo-1 mutant was the most salt-sensitive species. Taken together, our findings indicate that salt tolerance may be partly linked to the plants' ability to control Na(+) influx and to ensure appropriate K(+) nutrition, but is not linked to proline accumulation.
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Jolly, P. W. (1985). ?3-Allylpalladium Compounds. Angew. Chem. Int. Ed. Engl., 24(4), 283–295.
Abstract: This chapter contains sections titled:
Bis(η3-allyl)di-μ-chloro-dipalladium(II)
(η3-Allyl)(η5-cyclopentadienyl)palladium(II)
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Jolly, P. W. (1985). ?3-Allylpalladium Compounds. Angew. Chem. Int. Ed. Engl., 24(4), 283–295.
Abstract: This chapter contains sections titled:
Bis(η3-allyl)di-μ-chloro-dipalladium(II)
(η3-Allyl)(η5-cyclopentadienyl)palladium(II)
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Kralj Kuncic, M., Zajc, J., Drobne, D., Pipan Tkalec, Z., & Gunde-Cimerman, N. (2013). Morphological responses to high sugar concentrations differ from adaptation to high salt concentrations in the xerophilic fungi Wallemia spp. Fungal Biol, 117(7-8), 466–478.
Abstract: Fungi from the food-borne basidiomycetous genus Wallemia, which comprises Wallemia ichthyophaga, Wallemia muriae and Wallemia sebi, are among the most xerophilic organisms described. Their morphological adaptations to life at high NaCl concentrations are reflected in increased cell-wall thickness and size of cellular aggregates. The objectives of this study were to examine their growth and to define cell morphology and any ultrastructural cell-wall changes when these fungi are grown in low and high glucose and honey concentrations, as environmental osmolytes. We analysed their growth parameters and morphological characteristics by light microscopy and transmission and scanning electron microscopy. Wallemia ichthyophaga grew slowly in all of the sugar-based media, while W. muriae and W. sebi demonstrated better growth. Wallemia ichthyophaga adapted to the high glucose and honey concentrations with formation of larger cellular aggregates, while cell-wall thickness was increased only at the high glucose concentration. Wallemia muriae and W. sebi demonstrated particularly smaller sizes of hyphal aggregates at the high glucose concentration, and different and less explicit changes in cell-wall thickness. Adaptive responses show that the phylogenetically more distant W. ichthyophaga is better adapted to high salt conditions, whereas W. muriae and W. sebi cope better with a high sugar environment.
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