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J. MAURÍCIO S. BENTO TEREZINHA M. C. DELLA LUCIA RUTH R. DO NASCIMENTO JAN BERGMANN E. DAVID MORGAN 《Physiological Entomology》2007,32(3):283-286
Abstract. The secretion from the mandibular glands of males of the leaf-cutting ant Atta sexdens rubropilosa is responsible for the reaction of workers outside the nest at the time of sexual swarming. Workers respond with excitability and aggression when presented with the natural mixture of 4-methyl-3-heptanol and 4-methyl-3-heptanone, which is contained in the secretion of the male mandibular glands. Workers respond quickly to fractional amounts of one male equivalent. 4-Methyl-3-heptanone, from the virgin female mandibular glands causes much less response in workers, whereas an equimolar mixture of male and female pheromones gives a still less clear response. The male pheromone plays the most important part in the communication of workers outside the nest at this time. 相似文献
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LUCIA JARDIM DE MORAES FAGUNDES JAYME ANGLUSTER BENJAMIN GILBERT ISAAC ROITMAN 《The Journal of eukaryotic microbiology》1980,27(2):238-241
Ergosterol was the only sterol detected in Herpetomonas samuelpessoai grown in a defined, lipid-free medium. When cultivated in a complex medium, this flagellate was found to contain 6 additional sterols. As measured by incorporation of L-[Me-14C]methionine, in the absence of acetate, the sterol synthesis was greater at 28 C than at 37 C; in the presence of acetate, however, this synthesis was greater at 37 C. When [2-14C]acetate was used as the sterol precursor, the synthesis level at 37 C exceeded that at 28 C. 相似文献
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The establishment of a Cardiovascular Case Progress Index at the University of California School of Medicine is reported. The need for such an index to increase our knowledge of chronic cardiovascular diseases is discussed. Cases of various disorders of the cardiovascular system seen in a routine way in the hospital or outpatient department are listed in the Index, and their progress followed indefinitely. The organization, operation, and utilization of the Index for teaching and research are briefly discussed. 相似文献
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M. LUCIA CARDOSO DE ALMEIDA LINDA M. ALLAN MERVYN J. TURNER 《The Journal of eukaryotic microbiology》1984,31(1):53-60
Variant surface glycoproteins (VSG) of Trypanosoma brucei are released in a water soluble form on impairment of membrane integrity. We have previously shown that this release is the result of an enzyme-mediated event which converts the hydrophobic membrane form VSG into the hydrophilic water-soluble form. We now present further details of the methods by which membrane form VSG (mfVSG) may be isolated, uncontaminated by water-soluble VSG (sVSG). The sensitivity to different metal ions of the enzyme that mediated the conversion event is discussed, and some biochemical characteristics of different mfVSG preparations are presented. 相似文献
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Responses of Soybean Leaf Angle, Photosynthesis and Stomatal Conductance to Leaf and Soil Water Potential 总被引:2,自引:0,他引:2
The hypothesis that soil water potential (s) is better correlatedto heliotropic leaf orientation, photosaturated photosyntheticCO2 assimilation and stomatal conductance during periods oflimited water availability than is bulk leaf water potential(1) was examined in greenhouse-grown soybean (Glycine max) plants,submitted to a progressive drought. Paired plants were exposedto either 1000 or 100 µmol m2 s1 photonflux densities (PFD) for 4560 mins. The higher irradianceinduced short-term decreases in 1, due to increased transpiration,while l in the plant exposed to low PFD did not decrease. Thesechanges in 1 occurred independently of changes in soil waterstatus. Concurrent to the light treatments, a single attachedleaf from each of the two plants was isolated from the restof the plant by shading, and the pulvinus of its terminal leafletwas exposed to a perpendicular PFD of 500 µmol m2S1. Leaf movement of this leaflet was recorded in responseto this light, until a stable leaflet angle was achieved. Valuesof s and l (before and after light treatment), and photosaturatedrates of photosynthesis and stomatal conductance, were thenmeasured on these leaves. Leaflet angle and gas exchange werebetter correlated with s (r2 = 0.50, 0.50 and 0.57 for angle,photosynthesis and conductance, respectively) than with l especiallywhen l was the result of short-term, high-light induced changesin leaf water status (r2 = 0.36, 0.32 and 0.49, for the sameparameters). Leaflet angle was also correlated with stomatalconductance (r2 = 0.61) and photosynthetic rate (r2 = 0.60),suggesting a close association between leaf orientation, leafmetabolism and soil water availability. Glycine max (L.) Merr. cv. Essex, soybean, heliotropism, water potential, photosynthesis, stomatal conductance, solar tracking 相似文献
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Abstract: A rich, diverse Permian ostracod fauna has been recovered from the red and grey, laminated shales and quartz‐rich shales of the Triassic Lercara Formation. Forty‐seven species have been identified, 13 of which are newly described here; they belong to 26 genera of which three are new: Anahuacia lercaraensis sp. nov., Aurigerites siciliaensis sp. nov., Bairdia portellaensis sp. nov., Cristanaria? katyae sp. nov., Fabalicypris gruendeli sp. nov., Lethiersa salomonensis gen. et sp. nov., Lethiersia sinusoventralis gen. et sp. nov., Portella trapezoida gen. et sp. nov., Siciliella elongata gen. et sp. nov., Siciliella infernespinosa gen. et sp. nov., Siciliella prima gen. et sp. nov., Siciliella quadrata gen. et sp. nov., and Siciliella spinorobusta gen. et sp. nov. The assemblages contain or are composed of palaeopsychrospheric forms, which are regarded as index fossils for deep environments. The bathymetry of the different associations in life is evaluated. 相似文献
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A new Swartzia (Leguminosae: Papilionoideae: Swartzieae) species with trimorphic stamens from Amazonian Brazil 总被引:1,自引:0,他引:1
VIDAL DE FREITAS MANSANO ANA LUCIA DE SOUZA 《Botanical journal of the Linnean Society. Linnean Society of London》2005,147(2):235-238
A new species Swartzia trimorphica Mansano & A. L. Souza (Leguminosae, Papilionoideae, Swartzieae) from the Amazonian Brazil, is described and illustrated. The new species is notable and distinct from all the other species of Swartzia by its highly unusual trimorphic stamens, while the other species have either an isomorphic or a dimorphic androecium. The new species is included in the section and subsection Swartzia , ser. Orthostylae based on its bracteolate pedicels, the cauligerous inflorescences, lateral style and the relative size of the ovary compared to the style. The atypically small gynoecium in the material suggests the possibility that flowers may be functionally unisexual. Field observations and more collections are needed to resolve this question. © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 235–238. 相似文献
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