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71.
The monotypic genera Epiplagiops Blanchard, 1943 and Tetragrapha Brauer and Bergenstamm, 1891 are revised. Both are invalidated and synonymized with Chetogena Rondani, 1856. Their type-species, Epiplagiops littoralis Blanchard, 1943 and Tetragrapha tessellata Brauer and Bergenstamm, 1891, are studied, redescribed, illustrated, and transferred to Chetogena. A lectotype is designated for T. tessellata.  相似文献   
72.
73.
A series of alkyl 3,4-dihydroxybenzoates (protocatechuates) was synthesized, and their fungicidal activity against Saccharomyces cerevisiae was assayed using a 2-fold serial broth dilution method. Nonyl and octyl 3,4-dihydroxybenzoate were noted to be the most effective against this yeast with the minimum fungicidal concentration of 12.5 microg/mL each. The activity was found to correlate with the hydrophobic alkyl chain length. The time-kill curve study showed that nonyl 3,4-dihydroxybenzoate was fungicidal against S. cerevisiae at any growth stage and this activity was not influenced by pH values. The fungicidal activity of alkyl 3,4-dihydroxybenzoates was noted in combination with their ability to disrupt the native membrane-associated function nonspecifically as surface-active agents (surfactants) and to inhibit the respiratory electron transport. However, the primary fungicidal activity of nonyl 3,4-dihydroxybenzoate likely comes from its ability to act as a surfactant.  相似文献   
74.
Efforts to find the magnetic monopole in real space have been made in cosmic rays and in particle accelerators, but there has not yet been any firm evidence for its existence because of its very heavy mass, approximately 10(16) giga-electron volts. We show that the magnetic monopole can appear in the crystal momentum space of solids in the accessible low-energy region (approximately 0.1 to 1 electron volts) in the context of the anomalous Hall effect. We report experimental results together with first-principles calculations on the ferromagnetic crystal SrRuO3 that provide evidence for the magnetic monopole in the crystal momentum space.  相似文献   
75.
Sugars in the glycocalyx play an important role in the attachment of infectious agents to the respiratory mucosa. We examined the histochemistry of 23 lectins to survey the sugar expression in the glycocalyx of the respiratory mucosa of the Pacific white-sided dolphin, Lagenorhynchus obliquidens. The ciliated and basal cells were positive for all of the lectins studied. SBA, WFA, GSL-II, STL, S-WGA, and PNA staining in the cytoplasm showed different intensities between basal cells and ciliated cells. These results suggest that multiple terminal glycosylation occurs on ciliated and basal cells, such as GalNAc, GlcNAc, NeuNAc, galactose, glucose/mannose, oligosaccharide, and fucose, and that sugar residue expression changes during cell differentiation. The Pacific white-sided dolphin respiratory mucosa might express multiple sugar residues in the glycocalyx, to prevent the attachment and colonisation of infectious agents.  相似文献   
76.
Abstract

Maize (Zea mays L.) cv. Ganga 2 was grown in refined sand at three levels of copper: deficient (0.00065 mg L-1), adequate (0.065 mg L-1), and excess (6.5 mg L-1), each at three levels, deficient (0.00065 mg L-1), adequate (0.065 mg L-1), and excess (6.5 mg L-1) of zinc. Excess Cu magnified the zinc deficiency effects in maize by lowering further the biomass, the concentration of leaf Zn, activities of carbonic anhydrase, aldolase, and ribonuclease and intensified the visible foliar symptoms of Zn deficiency. The effects of Cu deficiency, low dry weight, the concentration of leaf Cu and activities of cytochrome oxidase and polyphenol oxidase were enhanced by excess Zn. Synergism was observed between combined deficiency of Cu and Zn and Cu or Zn deficiency, because the depression in the parameters characteristic of Cu or Zn deficiency was more pronounced when both Cu and Zn were deficient than when Cu or Zn was deficient. Antagonism was observed in some parameters between combined excess of Cu and Zn and Cu or Zn excess. Dry weight was decreased further when both Cu and Zn were in excess than when either Cu or Zn was in excess. After the infiltration of Cu and Zn together to the leaf discs from deficient Cu-deficient Zn treatment, the increase in the concentration of leaf Zn and the activities of aldolase, carbonic anhydrase, polyphenol oxidase, and cytochrome oxidase was more pronounced than after the infiltration of Cu or Zn singly. Discontinuance of excess Zn supply from the excess Zn-deficient Cu treatment increased the concentration of leaf Cu and activities of polyphenol oxidase and cytochrome oxidase and lowered the concentration of Zn. Similarly the discontinuance of excess Cu supply from the leaf discs in the “excess Cu-deficient Zn” treatment increased the leaf Zn concentration and the activities of carbonic anhydrase and aldolase.  相似文献   
77.
Environmental samples of soil, plant and air dust collected after the Fukushima Daiichi Nuclear Power Plant accident were analyzed by autoradiograph, and significant amounts of radioactive particles containing higher cesium-134 (134Cs) and cesium-137 (137Cs) were found. Most of the radioactive soil particles were clay sized. The main part of the radioactivity and radioactive particles of air dust was detected from the 1.1–2.0μm fraction of an Andersen sampler filter. A considerable part of the radioactive particles on the air dust filter were not water soluble. Radioactive particles attached to outdoor plant leaves persisted for nearly 1 year. Thus, soil, leaf and air dust similarly contained sparingly water-soluble, micron-sized radioactive particles each with comparable ranges of elevated radio-Cs. A sheet dilution method was proposed and used to select and purify these radioactive particles. Using selected radioactive particles, the relation between area × gray value on autoradiograph and radioactivity was estimated. Radioactivity per particle was up to a few Bq and the geometrical average radioactivity of detected particles was around 0.1 Bq per particle or less. The configuration, chemical composition, origin and formation mechanisms of the radioactive particles require clarification.  相似文献   
78.
Near-infrared spectra of Jupiter's small inner satellites Amalthea and Thebe are similar to those of D-type asteroids in the 0.8- to 2.5-micrometer wavelength range. A deep absorption feature is detected at 3 micrometers in the spectra of the trailing side of Amalthea, which is similar to that of the non-ice components of Callisto and can be attributed to hydrous minerals. These surface materials cannot be explained if the satellite formed at its present orbit by accreting from a circumjovian nebula. Amalthea and Thebe may be the remnants of Jupiter's inflowing building blocks that formed in the outer part or outside of the circumjovian nebula.  相似文献   
79.
This study was to investigate the time course of changes to the antioxidant activity of milk from cows fed a trehalose‐supplemented diet, and to determine possible underlying mechanisms for observed changes. Six Holstein cows were used, and subjected to two experimental feeding periods consisting of a 1% trehalose‐supplemented diet for 10 days, followed by a basal diet only (no trehalose) for 10 days. 1,1‐Diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging activities in milk were gradually increased during the trehalose supplementation period and were highest at the end of the second period. However, trehalose was not detected in the milk and plasma of dairy cows fed a diet supplemented with trehalose for 10 days, indicating that the increased antioxidant activity in the milk of trehalose‐fed cows is not due to the direct transfer of trehalose to the milk. Plasma DPPH activities exhibited a similar time course to that seen for milk. Relative superoxide dismutase (SOD) activities in the rumen were higher 3 days after the end of trehalose supplementation than at any other time during the experimental periods. These results suggested that the improved antioxidant activity in milk and plasma of cows fed a trehalose‐supplemented diet was due to improved ruminal relative SOD activity.  相似文献   
80.
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