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481.
The ability to generate alpha brainwaves has been associated with the self-regulation of stress. It has been suggested that generation of these brainwaves, above what is to be expected in a normal 24-hour EEG, contributes to an expanded state of consciousness. This study attempted to test Newman's theory that expansion of consciousness could be observed in perception of time passing. Twenty female college students were randomly assigned to an alpha brainwave training or beta (mock) brainwave training group. Following ten 30-minute training sessions over a five-week period of time, each subject in each group was asked to produce ten randomly assigned time intervals. Mean scores were obtained for each of the ten intervals for each group. An analysis of variance with repeated measures was used to analyze the time interval perceptions of each group. According to results obtained, both main effects and interaction effects were highly significant (p<.0001). This study offers a beginning effort to examine the consciousness altering capability of alpha brain-wave generation.The author wishes to acknowledge Dr. Alton J. DeLong for his generosity in reviewing this paper and offering such helpful support and suggestions. 相似文献
482.
Features of the underwater light climate just below the surface in some New Zealand inland waters 总被引:1,自引:0,他引:1
1. Using sampling rates of 8–64 Hz we found clear indications of extensive and high frequency fluctuations of underwater photosynthetically active radiation (PAR) just below the surface (0.016–1.1 m) in some New Zealand water bodies. High variability and flashing occurred down to at least 3 m depth.
2. PAR variability increased under the influence of bright sunshine if wind roughening of the surface took place. Concomitantly, the average PAR levels declined by about 10%. However, even when the surface was shaded, high variability of PAR persisted.
3. Under a calm surface, PAR irradiance followed a log normal distribution. This occurred independently of the presence of direct sunlight. However, when the surface was roughened by wind in sunshine, PAR immediately switched to a Gumbel (extreme value type EV1) distribution.
4. Neither wave action nor wave focusing of incident irradiance would explain the wide range of PAR close to the water surface, although both factors add to the PAR variability.
5. The data indicate that transmittance through the surface is highly variable at the temporal and spatial scales studied, and that the irregularity of the air–water interface is instrumental in bringing about the observed fluctuations of PAR just below the surface. 相似文献
2. PAR variability increased under the influence of bright sunshine if wind roughening of the surface took place. Concomitantly, the average PAR levels declined by about 10%. However, even when the surface was shaded, high variability of PAR persisted.
3. Under a calm surface, PAR irradiance followed a log normal distribution. This occurred independently of the presence of direct sunlight. However, when the surface was roughened by wind in sunshine, PAR immediately switched to a Gumbel (extreme value type EV1) distribution.
4. Neither wave action nor wave focusing of incident irradiance would explain the wide range of PAR close to the water surface, although both factors add to the PAR variability.
5. The data indicate that transmittance through the surface is highly variable at the temporal and spatial scales studied, and that the irregularity of the air–water interface is instrumental in bringing about the observed fluctuations of PAR just below the surface. 相似文献
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L. O. BJöRN 《Physiologia plantarum》1971,25(2):316-323
N-methyl phenozonium methosulfate,3–(3,4-dichlorophe-nyl)–l, l-dimethylurea and carbonylcyanide-m-chlorophenyl hydrazone have similar effects on the slow, far-red induced afterglow component in intact Elodea leaves as has previously been shown for Chlorella. The first compound increases the rate constant for emission. Contrary to the case with Chlorella, it also markedly increases the total amount of light emitted from 10 sec. to infinity (maximally by 50 percent). The second compound decreases the rate constant and the amount of light, and the third compound increases the rate constant and decreases the amount of light. Electron micrographs are compared with the hypothetical units that can be deduced from the afterglow experiments, and it is found that the small thylakoids (“grana thylakoids”) have a size of the same order of magnitude as that expected for the afterglow units. The afterglow from Elodea, in contrast to that from Chlorella, is not affected by desaspidin except at extremely high concentrations. Far-red induced glucose uptake in Chlorella is not affected by 10–7M N-methyl phenazonium methosulfate, which was previously shown to have a large effect on afterglow kinetics in the same organism. 相似文献
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Andrew J. Pittman 《Developmental biology》2010,344(2):784-794
In the zebrafish retinotectal system, retinal ganglion cells (RGCs) project topographically along anterior-posterior (A-P) and dorsal-ventral (D-V) axes to innervate their primary target, the optic tectum. In the nevermind (nev) mutant, D-V positional information is not maintained by dorsonasal retinal axons as they project through the optic tract to the tectum. Here we present a detailed phenotypic analysis of the retinotectal projection in nev and show that dorsonasal axons do eventually find their correct location on the tectum, albeit after taking a circuitous path. Interestingly, nev seems to be specifically required for retinal axons but not for several non-retinal axon tracts. In addition, we find that nev is required both cell autonomously and cell nonautonomously for proper lamination of the retina. We show that nev encodes Cyfip2 (Cytoplasmic FMRP interacting protein 2) and is thus the first known mutation in a vertebrate Cyfip family member. Finally, we show that CYFIP2 acts cell autonomously in the D-V sorting of dorsonasal RGC axons in the optic tract. CYFIP2 is a highly conserved protein that lacks known domains or structural motifs but has been shown to interact with Rac and the fragile-X mental retardation protein, suggesting intriguing links to cytoskeletal dynamics and RNA regulation. 相似文献
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