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111.
We used transport and Raman scattering measurements to identify the insulating state of self-doped spin (1/2) two-leg ladders of Sr14Cu24O41 as a weakly pinned, sliding density wave with nonlinear conductivity and a giant dielectric response that persists to remarkably high temperatures.  相似文献   
112.
We have determined the upper critical field Hc2 as a function of hole concentration in bismuth-based cuprates by measuring the voltage induced by vortex flow in a driving temperature gradient (the Nernst effect), in magnetic fields up to 45 tesla. We found that Hc2 decreased steeply as doping increased, in both single and bilayer cuprates. This relationship implies that the Cooper pairing potential displays a trend opposite to that of the superfluid density versus doping. The coherence length of the pairs xi(0) closely tracks the gap measured by photoemission. We discuss implications for understanding the doping dependence of the critical temperature Tc0.  相似文献   
113.
In this study, distribution coefficients (K d s) of five radionuclides (54Mn, 60Co, 65Zn, 85Sr, 137Cs) were measured by a batch technique for 36 agricultural soils (paddy and upland soils) collected in Japan. Twelve properties of the soils and measured K d ss were examined for their probability distributions. Soil properties showed log-normal type distributions, except pH(H2O), and total calcium and potassium contents for which distributions were normal. The K d s distributions were also lognormal types except for 54Mn-K d s? No significant difference in soil K d s was found between upland and paddy soils. The K d s were analyzed for correlations with each soil property. The combinations showing the highest correlation were: the exchangeable calcium for 54Mn and 60Co; the water content for 65Zn; the cation exchange capacity for 85Sr; and the exchangeable potassium for 137Cs, For 54Mn and 60Co, their K d s also correlated with supernatant pH. Only 85Sr-K d s showed an adequate correlation with the value if the CEC divided by the supernatant EC. For the other four nuclides, some other mechanisms besides ion exchange seemed to be working.  相似文献   
114.
5-Aminolevulinic acid (ALA) acts to increase chlorophyll biosynthesis, photosynthesis, cold stress tolerance, and salt tolerance at low concentrations. We studied the effects of ALA on H2 15O translocation from the roots to the shoots of rice plants (Oryza sativa L. cv. Nipponbare) in real time by a positron-emitting tracer imaging system (PETIS). When the plant was treated with 10 μm ALA, the velocity of the H2 15O translocation from 2 to 12 min after absorption increased to 126, 137, 140% that of the control at 1.5, 2.5, and 3.5 h after ALA treatment, respectively. However, ALA did not affect the H2 15O translocation within 0.5 h of treatment. When the plant was treated with 0.1 mM ABA at 4 h after 10 μm ALA treatment, the velocity of the H2 15O translocation decreased at 0.5 h after ABA treatment. Those observations suggested ALA might be absorbed and transported to the guard cells within 1.5 h and functioned to expand the stomatal aperture.  相似文献   
115.
Equine paratyphoid is caused by Salmonella enterica serovar Abortusequi, and manifests mainly as abortion in the mare. We compared S. Abortusequi strains isolated in Japan and other countries using pulsed-field gel electrophoresis (PFGE) and fluorescent amplified-fragment length polymorphism (FAFLP) analysis. PFGE analysis of S. Abortusequi strains gave 21-27 fragments ranging in size from 33 to 602kb. Although two PFGE profiles were observed among the 20 S. Abortusequi isolates in Japan, the restriction fragments originating from the chromosome were common between the two profiles. The similarity index of the two profiles was 90.9%, while those between Japanese and five other S. Abortusequi strains were 29.8-37.5%. On the other hand, FAFLP analysis of S. Abortusequi strains generated 64-67 amplified fragments ranging in size from 100 to 400bp. One polymorphic fragment was observed among the 20 S. Abortusequi isolates in Japan. These data indicate the close relation of this agent in Japan. S. Abortusequi strains sharing a common ancestry might have been conserved in Japan.  相似文献   
116.
117.
A six‐year‐old, neutered, female golden retriever was presented with generalised, dark purple to black cutaneous nodules and gastrointestinal haemorrhage. Histopathologically, all cutaneous nodules were diagnosed as benign cavernous haemangiomas. Endoscopic analysis revealed similar nodules in the oesophagus, stomach and duodenum. At laparotomy, similar nodules were seen on the visceral peritoneal lining of abdominal organs. Metastatic haemangiosarcoma was ruled out based on histological features and lack of primary tumour in spleen, liver or heart ultrasonographically. Blood loss associated with gastrointestinal haemorrhage was managed with blood transfusion. To the authors’ knowledge, this is the first canine case of multi‐system progressive angiomatosis resembling blue rubber bleb nevus syndrome in humans.  相似文献   
118.
Abstract

Further work with the herbicide C 19490 (S-(2-methyl-1-piperidyl-carbonylmethyl)-O,O-di-N-propyl dithiophosphate) in the mixture C 288 with the triazine C 18898 in the ratio 4:1, and with 2,4-D isopropyl ester (2,4-D IPE) in the ratios 2:1 and 3:2 have been completed. New toxicological data show that the risk of toxicity hazards to the user or to other mammals by contamination is low. Residue work shows that C 19490 leaves very low or undetectable residues in rice grain and soil, though C 18898 was detected in both, but never at more than 0.28 ppm in soil or more than 0.04 ppm in grain. There was no interaction between either C 19490 or C 288 and commonly used insecticides. Uptake of the products by plants was shown to be preferentially through emerging shoots, and less through roots.

Field trials resulted in recommendations for around 2 kg C 288 total a.i./ha in Japan, optimum timing depending on the prevailing temperature. Successful control was achieved in Taiwan with C 288 at 1 kg a.i./ha in both the cool and warm season crops, applied 7–12 days after transplanting. In equatorial Asia, mixtures worked well: C 288 at 0.75–1.25 kg a.i./ha, C 19490 at 0.75–1.0 + 2,4-D IPE at 0.5 kg a.i./ha and the 3:2 mixture at 0.75 + 0.5 kg a.i./ha (granular), applied four DAT on dense weed stands, but up to ten DAT on stands comprising predominantly moderate infestations of Echinochloa crusgalli, Monochoria vaginalis and annual Cyperus spp. These recommendations resulted in yields which were never significantly different from those of hand-weeded areas. On light, permeable soils, e.g. in Pakistan, C 288 at 1.0–1.25 kg a.i./ha, 8–10 DAT was less harmful to the crop than lower rates applied earlier, and was better than the 2,4-D IPE mixture for weed control. In Egypt, C 19490 + 2,4-D IPE at only 0.375 + 0.25 kg a.i./ha was successful, because of the susceptible weed flora.  相似文献   
119.
The pituitary gland is present in all vertebrates, from agnathans (jawless vertebrates) to mammals, but not in invertebrates. Reproduction in gnathostomes (jawed vertebrates) is controlled by two pituitary gonadotropins (GTHs), luteinizing hormone and follicle-stimulating hormone, which are part of the pituitary glycoprotein hormone (GPH) family. Hagfishes, which lack both jaws and vertebrae, are considered the most primitive vertebrate known, living or extinct. Accordingly, they are of particular importance in understanding the evolution of the pituitary GPHs and their functions related to vertebrate reproduction. Nevertheless, key elements of the reproductive endocrine system in hagfish have yet to be elucidated. Our current report has revealed the first identification of a functional GPH composed of two subunits that possess gonadotropic action at the pituitary of brown hagfish. It seems most likely that an ancestral GPH gave rise to only one GTH in hagfish pituitary and that multiplicity of GPHs arose later during the early evolution of gnathostomes. This paper briefly summarizes the latest findings on the hagfish GPH from an evolutionary point of view.  相似文献   
120.
In order to monitor the fish volume entrapped over time in a set net in real time, a new remote fish finder system based on a mobile network was developed and tested. This system was designed with a client/server architecture including an echo sounder terminal, a web server, and some end user display terminals, which allowed fishermen to monitor the fishing state of a set net via any display device. In addition, in order to transfer the echo data smoothly via a mobile network, a fish echo extraction method based on image processing and a data organization structure were proposed, which can significantly reduce the data volume for transmission, supply sufficient information to reconstruct the high resolution echogram at the user terminals, and calculate the positional and morphometric parameters of fish echoes. Furthermore, a semiautomatic data recording method for use with a database was proposed to manage the extracted fish echo data and the fishing records. The functions and capabilities of the new system were demonstrated by a sea trial.  相似文献   
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