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31.
  1. To test the scheme proposed in a preceding paper (2), the actionspectra for Hill activities and fluorescence properties weremeasured using variously-treated particle II preparations (P-II).
  2. The action spectrum for ferricyanide photoreduction by intactP-II was characterized by two clear peaks at approximately 686nm and 648 nm, whereas that for DPIP photoreduction had onlyone peak at about 686 nm.
  3. The two peaks in the action spectrumfor ferricyanide photoreductionby intact P-II were significantlyinfluenced by various treatments;Tris-treatment and antimycinA inhibition resulted in loss ofthe 686 nm-peak, whereas preilluminationtreatment and CCCPinhibition brought about the disappearanceof the 648 nm-peak.
  4. Aging treatment produced a characteristiceffect. The 648 nm-peakdiminished gradually with the progressof aging, and only the686 nm-peak was observed after agingbeyond 70 hr.
  5. Fluorescence properties of variously-treatedP-II were examined:Aging treatment resulted in the disappearanceof the fluorescenceof the 730 nm-component.
  6. These findingsprovide further support for the idea that thetwo photoreactiortsdescribed above are involved in photosystemII of green plantphotosynthesis. Possible roles of the twophotoreactions inphotosystem II are discussed.
(Received February 28, 1973; )  相似文献   
32.
Summary The intact male nymph cricket, Gryllus bimaculatus DeGeer, was found to show mating-like behavior, that is, courtship-like behavior (CSLB) and copulation-like behavior (CPLB), in the 7th and 8th (last) instars. The 8th instar nymph exhibited less CSLB and CPLB than the adult but much more than the 7th instar nymph. The movement patterns of CSLB and CPLB were essentially the same as those of adults except for motor acts requiring the use of the genitalia. CSLB was short and often ceased spontaneously before it switched to CPLB. CPLB also ended earlier than in adults. The occurrence of CSLB and CPLB was almost zero the few days around ecdysis. The nymph was very sensitive to disturbance, so that he often stopped courtship for more than 30 min after stimulation. CSLB was similarly induced in the male nymph (8th instar) by pairing with a female adult, male adult, female nymph (8th) and male nymph (8th). The female nymph (8th) was observed to mount not only the male adult but also the male nymph (8th). A fixed time sexual refractoriness forming a basis of cyclical mating activity was not present after CPLB in the nymph. It appeared in association with the emergence of spermatophore protrusion behavior around day 3 after the imaginal molt. In fledglings, there were some transitions during the sexual maturation process, such as failures in hook hanging, spermatophore extrusion, and spermatophore transfer to the female. The decerebration experiments on nymphs and fresh adults agreed with behavioral observations. These results suggest that the development of mating behavior in the male cricket is a process of enhancement of basic motor patterns but not a process of addition of new movements by changes in pattern generation circuits in the central nervous system.Abbreviations CPLB copulation-like behavior - CPPT interval between copulation and spermatophore protrusion - CSCP interval between calling song and copulation - CSLB courtship-like behavior - CSS courtship song - PTCS interval between spermatophore protrusion and calling song - SPE spermatophore extrusion  相似文献   
33.
Abstract. We used classification tree analysis to develop a climate‐based distribution model for Fagus crenata forests in Japan. Four climatic variables judged likely to affect the distribution of the species (summer and winter precipitation, minimum temperature of the coldest month and Kira's warmth index) were chosen as independent variables for the model. Latitudinal and longitudinal information was also used to examine effects of spatial autocorrelation on the model. The climatic factors associated with the distribution of the forests were analysed using a classification tree to devise prediction rules. Predicted areas of high probability for forest occurrence lay mainly on the Sea of Japan side of northern Honshu and southern Hokkaido. This is consistent with actual forest distribution. Some areas with high predicted probabilities of F. crenata forest occurrence were beyond the current natural northern range limits of these forests. Since these areas were widely scattered, it was assumed that the species has been hindered from colonizing them due to dispersal limitations. Deviance‐weighted scores, used to compare magnitudes of the contributions of predictor variables, revealed winter precipitation as the most influential factor, followed by the warmth index, the minimum temperature of the coldest month and summer precipitation. Attempts were made to generate ecological explanations for the effects of the four climatic factors on the distribution of F. crenata forests.  相似文献   
34.
A prodecure for the quantitative determination of lysinoalanine (LAL) by gas chro-matography-selected ion monitoring was developed. α,ε-Diaminopimelic acid was chosen as the internal standard, and the content of LAL in commercial foods was analyzed. Of the samples analyzed, the content was highest in pidan. Wheat flour-based products (Chinese noodles, pretzels and crackers) and milk products (condensed milk and lactic acid beverages) also contained a significant amount of LAL. Ordinary milk, soybean (soy milk and soy protein isolate) and meat products (ham and Hamburg steak) contained a low amount of LAL. It was confirmed that the possibility of low-level LAL formation existed in foods cooked at home without any alkaline treatment.  相似文献   
35.
We designed a rapid, simple and sensitive method for the determination of norepinephrine (NE) and its metabolites by reversed-phase high-performance liquid chromatography (HPLC) with electrochemical detection. NE, 3,4-dihydroxymandelic acid (DOMA), and 3,4-dihydroxyphenylglycol (DOPEG) were adsorbed on alumina and eluted with 0.2 N HCl. From the remaining solution, normetanephrine and 3-methoxy-4-hydroxyphenylglycol (MOPEG) were extracted with ethyl acetate in the presence of both borate buffer and K2HPO4. Vanillylmandelic acid was extracted with ethyl acetate after acidification of the solution with concentrated HCl. The combined ethyl acetate phase was evaporated and the residue was dissolved in 0.1 N HCl. A 50 μl aliquot of each eluate or solution was injected onto the HPLC. Detection limits ranged from 300 pg to 1 ng per initial sampla. We used this method to determine substances in the medium following incubation of the rat vas deferens. Approximately 110 and 80 ng/g/10 min of DOPEG and MOPEG, respectively, were present under normal conditions. The electrical stimulation of tissues from the rat vas deferens led to increases in the levels of NE, DOPEG, DOMA and MOPEG. Normetanephrine and vanillylmandelic acid were not detected in the medium. This is probably the first documentation of the endogenous levels of NE and all its metabolites in medium containing tissue of the sympathetic nervous system.  相似文献   
36.
We developed an accurate and simple method for measuring thephytic acid contents in cereal grains on the basis of closeexamination of various factors affecting the accuracy and reproducibilityof the measurement. Our conclusions were: (1) As extracting medium for phytic acid,HCl was better than trichloroacetic acid or H2SO4. (2) The suitablepH range for extracting phytic acid was 0.3 to 1.0. (3) Completeformation of Fe-phytate required four to nine times as muchFe3$ as phytic acid. (4) No definite effect of Na2SO4 on therecovery of phytic acid was observed, though it increased theextracting efficiency of trichloroacetic acid. (5) The determinationlimit of phytic acid by the iron precipitation method was 3.3µmol per 20 ml. Our new method gave reliable results, and a linear relationshipof y=0.3163x$0.0597 was obtained up to 0.025 µmol µ–1between the concentration of phytic acid and the zone lengthin isotachophoresis. The phytic acid contents of two kinds ofrice, two kinds of rye, and one kind of wheat and of barleywere determined with this method. (Received March 19, 1985; Accepted August 2, 1985)  相似文献   
37.
Question: How much is the probability distribution of Fagus crenata forests predicted to change under a climate change scenario by the 2090s, and what are the potential impacts on these forests? What are the main factors inducing such changes? Location: The major islands of Japan. Methods: A predictive distribution model was developed with four climatic factors (summer precipitation, PRS; winter precipitation, PRW; minimum temperature of the coldest month, TMC; and warmth index, WI) and five non‐climatic factors (topography, surface geology, soil, slope aspect and inclination). A climate change scenario was applied to the model. Results: Areas with high probability (> 0.5) were predicted to decrease by 91%, retreating from the southwest, shrinking in central regions, and expanding northeastwards beyond their current northern limits. A vulnerability index (the reciprocal of the predicted probability) suggests that Kyushu, Shikoku, the Pacific Ocean side of Honshu and southwest Hokkaido will have high numbers of many vulnerable F. crenata forests. The forests with high negative sensitivity indices (the difference between simulated probabilities of occurrence under current and predicted climates) mainly occur in southwest Hokkaido and the Sea of Japan side of northern Honshu. Conclusion: F. crenata forest distributions may retreat from some islands due to a high WI. The predicted northeastward shift in northern Hokkaido is associated with increased TMC and PRS. High vulnerability and negative sensitivity of the forests in southern Hokkaido are due to increased WI.  相似文献   
38.
A possibility has been suggested of applying the EPS produced by Rhodococcus rhodochrous strain S-2 (S-2 EPS) to the bioremediation of oil-contaminated environments, because its addition, together with minerals, to oil-contaminated seawater resulted in emulsification of the oil, increased the degradation of polyaromatic hydrocarbons (PAH) of the oil, and led to the dominance of PAH-degrading marine bacteria. To understand the underlying principles of these phenomena, we determined the chemical structure of the sugar chain of S-2 EPS. The EPS was found to be composed of D-galactose, D-mannose, D-glucose, and D-glucuronic acid, in a molar ratio of 1:1:1:1. In addition, 0.8% (w/w) of octadecanoic acid and 2.7% (w/w) of hexadecanoic acid were also contained in its structure. By 1H and 13C NMR spectroscopy, including 2D DQF-COSY, TOCSY, HMQC, HMBC, and NOESY experiments, as well as chemical and enzymatic analyses, the polysaccharide was shown to consist of tetrasaccharide repeating units with the following structure: (see formula in text).  相似文献   
39.
In order to clarify the effect of molecular structure on the nature of azeotropic transformations in mixed monolayers, many systems of the positive and negative azeotropic types are examined in this study. Two-dimensional phase diagrams and apparent molar energy changes which are associated with the phase transition from the liquid-expanded to the liquid-condensed state are evaluated using a previously developed thermodynamic treatment. There is a maximum in the phase diagram of the positive azeotropic type and the excess apparent molar energy change is positive over the entire compositional range. Steric hindrance of the hydrophilic groups seems to be the important factor in the behavior of the positive azeotropic type. For the negative azeotropic type there is a minimum in the phase diagram and the excess apparent molar energy change is negative over the entire compositional range. The two long acyl chains of dipalmitoyl lecithin leads to a strong interaction between the two components.  相似文献   
40.
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