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1.
Abstract. A technique for fine-scale vegetation mapping with the aid of low-altitude aerial photography was developed. The procedure is as follows: 1. The site is divided into a lattice pattern - in case the site is too large to fit into a single photograph with satisfactory resolution. The coordinates of every lattice point are surveyed to be used as control points for geometric correction. A photograph of each block of the lattice is taken using a remote-controlled camera system lifted by a captive helium balloon. 2. The vegetation is classified on the basis of a phytosociological survey. 3. The shapes and locations of vegetation patches appearing in the photographs are entered into a computer, using a digitizer. A geometric correction is carried out through coordinate transformation referring to the coordinates of the control points and subsequently a draft vegetation map is produced. Finally, discrepancies are corrected and the map is coloured to produce the final version of the vegetation map. This technique was applied to vegetation mapping at a bar, 500 m wide and 2 km long, in the river Yoshino in Shikoku, Japan. A fine-scale vegetation map was obtained and used to analyse the influence of plants on geomorphic processes and community-specific hydrogeomorphic conditions on the bar.  相似文献   
2.
Uptake of sodium cefoxitin, D-phenylalanine and insulin into human red blood cells was significantly enhanced by the presence of salicylate and 5-methoxysalicylate in the medium. The mechanism of adjuvant action appeared to depend on an affinity between the adjuvant and the protein fraction in the erythrocyte membrane. The inhibitory effect of DIDS and phlorizin on the salicylate-enhanced uptake of these compounds strongly suggests that the ability of salicylate to permeate the membrane may be essential for it to act as an adjuvant.  相似文献   
3.
4.
ß-Tubulins from fourteen benomyl-resistant strainsof the homobasidiomycete Coprinus cinereus, which carry thebenA, benB, benC or benD mutations, were analyzed by urea SDS-PAGEor isoelectric focusing and subsequent immunoblot analysis.Electrophoretic aberrations in a major ß-tubulin isotype,denoted ß1 were found in two strains, BEN154 and BEN215,both of which carry benomyl resistance mutations in benA + Theaberrations of ß1 in BEN154 and BEN215 cosegregatedwith benomyl resistance among the progeny of outcrosses of BEN154 and BEN215 to wild type, indicating that the ß1aberrations were caused by the benA mutations. Both the mutantand wild-type ß1 tubulins were present in the heterozygousdikaryons, BEN 154/wild-type and BEN215/wild-type, ruling outpost-translational modification as a possible cause for theaberrations in ß1. Thus, we conclude that benA isa structural gene for ß1. Transhyphal migration ofnuclei in dikaryosis was blocked in the mycelia of BEN 154 andin its progeny that carried benA (ß1 mutation), demonstratingthat microtubules are involved in the migration process. Nuclearmigration in dikaryosis seems to differ in terms of mechanism,at least in part, from the migration of tetrad nuclei from basidiainto prespores during formation of basidiospores and from themigration of nuclei from basidiospores into hyphae during germination,because a benA mutation blocked the former without affectingthe latter two processes. (Received May 19, 1989; Accepted August 30, 1989)  相似文献   
5.
Carrot and tobacco plants were transformed with Agrobacteriumtumefaciens harboring wild-type, aux or cyt Tiplasmids. In tobacco, these wild and mutant Ti plasmids inducedthe formation of non-morphogenic galls, galls with shoots, andgalls with roots, respectively. In carrot, however, transformationwith any of these plasmids resulted in only the formation ofamorphous tumors. Determination of IAA and cytokinin contentsshowed that in tobacco, significantly high amounts of cytokininsor IAA are present in the cells transformed with Ti plasmidspossessing cytokinin or IAA biosynthetic genes, respectively.In carrot, cytokinin contents were also high in the cells transformedwith Ti plasmids having cytokinin biosynthetic genes, whereasIAA contents of the cells were similar regardless of the plasmidsused for transformation. These results suggest that the mechanism regulating IAA metabolismmay be different in tobacco and carrot. (Received June 25, 1987; Accepted February 1, 1988)  相似文献   
6.
IAA biosynthetic activity was examined in cultured carrot tissuestransformed with Agrobacterium tumefaciens harboring wild-type,aux or cyt Ti plasmids. In vitro IAAM hydrolaseactivities in tissues transformed with wild-type, and cytTi plasmids were 3.09 and 19.82 nmol/g proteins/30 min, respectively,but not detectable when aux Ti plasmids were used. Theactivity of IAA biosynthesis, determined by the incorporationof radioactivity into IAA in tissues fed with [14C]-tryptophan,was 34.13, 10.92 and 32.47 pmol/g fr wt/30 min in tissues transformedwith wild type, aux and cyt Ti plasmids, respectively.The incorporation of radioactivity into the IAAM fraction wasdetected only in the tissues transformed with wild type andcyt Ti plasmids. These results showed that the T-DNAencoded pathway of IAA biosynthesis was active in tissues transformedwith wild-type and cyth Ti plasmids, and that the activity ofIAA biosynthesis in those tissues was higher than that in tissuestransformed with the aux Ti plasmid. (Received March 16, 1988; Accepted July 31, 1988)  相似文献   
7.
The changes in cerebral metabolism in mice in severe hypoxia were investigated by analyses of changes in the levels of energy metabolites and near-infrared spectrophotometric assessment of the states of hemoglobin and cytochrome oxidase. Under 4.4% O2, the contribution of anaerobic ATP production was at most about 20% of the demand. However, the cerebral ATP level was kept at the control level until about 1 min before death. Pentobarbital anesthesia, which reduced the cerebral rate of metabolism, prolonged the survival time, although anaerobic ATP production still did not support ATP demand. Under these conditions, deoxygenation of hemoglobin and reduction of cytochrome oxidase proceeded rapidly within 1 min. Hemoglobin reached the maximum state of deoxygenation in the middle phase of hypoxia, with no further change until death. However, cytochrome oxidase was reduced slowly with one phase of partial reoxidation due to increase of cerebral blood volume, and reached the completely reduced state at death. From these results it was concluded that the aerobic ATP synthesis, which supplied more than 80% of the cerebral demand, decreased gradually because of limitation of oxygen supply, and that the failure of oxidative phosphorylation to meet demand triggered the decrease in the cellular ATP level that led to death.  相似文献   
8.
9.
Methylococcus capsulatus (Bath) possesses methane monooxygenases (soluble - (sMMO) and particulate - (pMMO)) which are able to catalyse the epoxidation of propylene to propylene oxide. In a previous paper we have shown that the production of the epoxide caused a rapid inactivation of the bioconversion process (Stanley et al, 1992). This paper shows that cultures containing pMMO, inactivated by propylene oxide production, could be completely reactivated in the presence of growth substrates within 5 h after the removal of propylene oxide so long as the propylene oxide production rate was below 150 nmol min-1 [mg dry weight cells]-1. Reactivation under these conditions was detectable within 30 min of propylene oxide removal. On the other hand, cells inactivated by propylene oxide production rates in excess of 150 nmol min-1 [mg dry weight]-1 did not begin to recover activity within the 30 min period. Furthermore a lag period was observed before reactivation began which was dependent upon the initial production rate. Cultures possessing sMMO took twice as long to recover their activity compared with cells containing pMMO.

Reactivation of propylene oxide production could occur without growth, but the process required the presence of a carbon and energy source (methane or methanol), sulphur, nitrogen and oxygen, although copper (which is normally involved in pMMO activity) was not required. It was shown that de novo protein synthesis was required for reactivation of activity.

Production rates of 12 g 1-1 d-1 could be maintained for longer than three weeks in a single phase production process and rates up to 30 g 1-1 d-1 were achieved in a two stage process. Using Methylocystis parvus (OBBP) rates of up to 90 g 1-1 d-1 were attained over a one week period.  相似文献   
10.
Stipe elongation during basidiocarp maturation in the wild-type,#5026+5132, and the elongationless mutant, NG0398, of Coprinusmacrorhizus was studied, and the following results were obtained.
  1. In the wild-type the middle zone of the stipe elongated 8.4times in 15 hr during maturation, while in the mutant it elongatedoaiy 2.2 times.
  2. Component cells of the stipe elongated inparallel with thestipe elongation in both the wild-type andthe mutant. The widthof stipe cells was almost constant duringelongation in thewild-type, while it increased 2 times in themutant. Cell volumeincreased ca. 8 times in both stocks.
  3. Theosmotic value of stipe cells was almost constant (0.45–0.50M) throughout elongation of both the wild-type and the elongationlessstipes.
  4. Mechanical properties of the cell wall were examinedby measuringshrinkage, extensibility and minimum stress-relaxationtime(To) of the stipe during maturation. These parameters weredirectlyproportional to the elongation rate to follow.
  5. Whenthe wild-type stipes were incubated in various concentrationsof mannitol solution and then in plain buffer solution, theextensibility of the stipe after the incubation in mannitolsolutions changed proportionally with the stipe length afterthe mannitol treatment, and To with the elongation capacityin plain buffer solution.
(Received March 3, 1977; )  相似文献   
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