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911.
F. Gribakin E. Alekseyev S. Shukolyukov M. Gogala 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1995,177(2):201-206
The spectral sensitivity of 21 eye preparations of Ascalaphus (Libelluloides) macaronius (Insecta, Neuroptera) has been re-measured using an up-to-date spectral scan method. 1. Dorso-frontal and ventro-lateral eyes have different spectral characteristics with peaks of sensitivity at 329 ± 8 nm (n = 15) and 343 ± 4 nm (n = 5) (P = 0.002), respectively. 2. The absorbance of the visual pigment layer, K, determined from the shape of the spectral sensitivity curves is 1.3 ± 1.8(n = 15) for dorso-frontal eyes and – 1.0 ± 0.3(n = 5) for ventrolateral eyes, thus implying higher selfscreening in the dorso-frontal eyes and narrowing of the spectral sensitivity curves as regards to a template visual pigment in ventro-lateral eyes. 3. Plotting K versus spectral sensitivity peak wavelength max revealed an inverse correlation between these variables with K = 42.5 – 0.126 max at r = 0.88(n = 19). 4. Extracts of ommochromes and carotenoids (Figs. 4 to 6) do not allow to account for the above diversity of optical properties of the Ascalaphus eye (Fig. 7).Abbreviations
SSC
spectral sensitivity curve
-
DF
dorso-frontal eye
-
UV
ultraviolet
-
VL
ventro-lateral eye 相似文献
912.
J. M. Ellingson L. J. Fleishman E. R. Loew 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1995,177(5):559-567
The visual pigments and oil droplets in the retina of the diurnal gecko Gonatodes albogularis were examined microspectrophotometrically, and the spectral sensitivity under various adapting conditions was recorded using electrophysiological responses. Three classes of visual pigments were identified, with max at about 542, 475, and 362 nm. Spectral sensitivity functions revealed a broad range of sensitivity, with a peak at approximately 530–540 nm. The cornea and oil droplets were found to be transparent across a range from 350–700 nm, but the lens absorbed short wavelength light below 450 nm. Despite the filtering effect of the lens, a secondary peak in spectral sensitivity to ultraviolet wavelengths was found. These results suggest that G. albogularis does possess the visual mechanisms for discrimination of the color pattern of conspecifics based on either hue or brightness. These findings are discussed in terms of the variation in coloration and social behavior of Gonatodes.Abbreviations
ERG
electroretinogram
-
MSP
microspectrophotometry
-
UV
ultraviolet
- max
wavelength of maximum absorbance 相似文献
913.
The subcellular distribution of membrane-bound ATPases was compared among terrestrial plants, seagrasses and marine algae by cytochemical techniques. High ATPase activity was detected in the copiously invaginated plasma membrane that was characteristic of transfer cells but not in the tonoplast of epidermal cells in mature leaves of seagrasses. Magnesium- or Ca2+-dependent ATPase activity was induced together with the characteristics of transfer cells during the development of leaf tissues able to resist seawater. Northern hybridization revealed the effective induction of the synthesis of mRNA for plasma-membrane H+-ATPase during the development of leaves. Such high ATPase activity was not detected in the smooth plasma membranes of marine macro-algae but was found in the membranes of some cytoplasmic vesicles or microvacuoles, providing evidence of the excretion of salts by exocytosis. It appears, therefore, that two essentially different methods for excreting excess salts have developed separately in these two classes of marine plants. The evolution of mechanisms of salt tolerance in the plant kingdom is discussed in terms of the differential subcellular distribution of ATPase activity.Abbreviation PCR
polymerase chain reaction
The authors are grateful to Dr. P. Park of Teikyo University, School of Medicine, and Dr. K. Kasamo, National Institute for Food Sciences, Tsukuba, for their helpful advice. This work was supported by the Japanese Salt Science Research Foundation (No. 9228). 相似文献
914.
The structure of planktonic copepod assemblages in a by-passedDanube section, and in the adjacent floodplain water bodies,haschanged since the Gabcíkovo hydropower plant was putintooperation. The greatest change occurred in a former side arm(upstream of the village of Dobrohosí), which driedout.Changes were observed in the parapotamon-type side armssituatedbetween river km 1840 and 1820, fed artificially with waterfromthe head-race canal. The abundance of euplanktonic copepodspeciesdecreased, while that of tychoplanktonic species increased.Summerzooplankton biomass decreased. Definitive, but less extreme,changes occurred in the copepod assemblage in the open-waterareasof the former main channel of the Danube, and in theplesiopotamon-type side arms in the affected river section.These results suggest that the water supply provided to theby-passed floodplain is unable to maintain the previoushabitatdiversity, nor its planktonic assemblages speciesdiversity. 相似文献
915.
Arnold Tukker René Kleijn Lauran van Oers Edith Smeets 《Journal of Industrial Ecology》1997,1(4):93-116
This article describes a method that combines substance flow analysis (SFA) and life-cycle assessment (LCA). It was used to provide a focus in the heated Swedish polyvinylchloride (PVC) debate. For Sweden's PVC chain, all emissions related to PVC were inventoried and translated into LCA-theme scores. The theme scores were compared with total theme scores for all Swedish processes and were benchmarked on the basis of PVC's contribution to Sweden's gross national product (GNP). Mass flows oftwo PVC additives, lead and organotin, were compared with the total use of these metals in Sweden. PVC's contribution to global warming, smog formation, and waste volume was equal to or less than the benchmark. After implementation of planned measures, emissions of the toxic substances dioxins, mercury, and lead will be below the benchmark. We recommend that the Swedish PVC debate concentrate on the uncertainties of the effects of phthalates, small process emissions of persistent chlorinated substances (PBTs), lead and organotin in landfilled PVC, and emissions from PVC in accidental fire 相似文献
916.
Abstract One fragment of the Oedaleus asiaticus entomopoxvirus (OaEPV) DNA cleaved with Bgl I was cloned into the EbmHI site of GEM-7zf(+) and then labeled by random oligonucletide primer to be a cloned DNA probe. This probe had species specificity to Dociostaurus kruussi EPV and Nosema to custae , but not to Calliptomus italicus EPV. The probe was able to detect Ing OaEPV DNA, 102 viral spheroids and OaEPV in the infected grasshopper homogenates. 相似文献
917.
Ian D. Ireland Darren F. Lewis Xing-Fang Li Annika Renborg Sarah Kwong Min Chen Norman J. Dovichi 《Journal of Protein Chemistry》1997,16(5):491-493
Capillary electrophoresis with laser-induced fluorescence detection (CE-LIF) is a promising new method for the analysis of protein sequencing products. It gives 10 zmol (1 zmol = 10–21 mol) limits of detection (3) for fluorescein thiohydantoin (FTH) amino acids. We have developed a separation for the (FTH)-amino acid products generated from 18 of the 20 coded amino acids. The extremely low volume requirement associated with CE-LIF makes it incompatible with commercial sequencers. For this reason, we have also been developing a miniaturized sequencer that can be more easily coupled to our detection system. Both the CE-LIF system and the miniaturized sequencer are described. 相似文献
918.
919.
K. Arikawa H. Uchiyama 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1996,178(1):55-61
1. | The ommatidia of the butterfly Papilio have a fused and tiered rhabdom. The distal tier of the rhabdom is made up of four distal photoreceptors (R1–4), whereas the proximal tier is made up of four proximal (R5–8) and one basal photoreceptor cell (R9). |
2. | We first confirmed by light microscopy that the ommatidia of Papilio are not twisted, i.e. have the same spatial organization all about the longitudinal axis. The polarization method, previously applied to the distal tier, hence is applicable to identify the photoreceptor location from the peak angle of the polarization sensitivity. |
3. | We determined the polarization and spectral sensitivity of in total 109 proximal and basal photoreceptors in the lateral looking eye region. All of the photoreceptors were either green or red type, most of which fall into three classes as judged by the peak angles of the polarization sensitivity: around 40°, 150°, and 180° (= 0°) with respect to the dorso-ventral axis. The first two classes are formed by the proximal photoreceptors with straight microvilli oriented at the average angle of 39° (R6, 8) and 144° (R5, 7) respectively, and the third is formed by the basal photoreceptors R9 with straight microvilli oriented at 180° (= 0°). The mean polarization sensitivity (PS = maximal sensitivity/minimal sensitivity) was about 2. |
4. | 75% of the proximal and 48% of the basal photoreceptors were of the red type. |
5. | A single ommatidium of Papilio appears to contain two to four types of spectral receptors. |
920.
记录和测定了视觉剥夺猫(dark-rearedcats)外膝体344个细胞的方位调谐等感受野特性,多数细胞(82%)具有方位敏感性(Bias>0.1)。最优方位的分布与正常猫类似,偏向于水平方位,但分布特性强于正常猫。与正常猫类似,视觉剥夺猫外膝体细胞的最优方位与该细胞感受野在视网膜上的位置有关,偏向平行于视网膜中心区与感受野中心的连线(向心线);外膝体内位置相邻近的细胞具有相近的最优方位,亦呈现初步有序排列。结果表明:外膝体细胞最优方位的分布特性与后天视觉经验无关而可能来源于遗传因素。 相似文献