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11.
A rapid 5'-labeling method of single-stranded DNA/RNA was developed, which is based on the utilization of an adenylated intermediate in the reaction of T4 RNA ligase. This method is commonly useful for fluorescence-, isotope- or biotin-labeling of the 5'-ends of both oligo- and polynucleotides.  相似文献   
12.
Laboratory Rainfall-Induced Slope Failure with Moisture Content Measurement   总被引:5,自引:0,他引:5  
The development of a physically based warning system for rainfall-induced slope failures requires a comprehensive understanding of the failure process. A set of laboratory-scale soil slopes was subjected to instability, through three different modes of raising water level, to clarify the process of failure initiation. Hydrologic responses of the model slopes to the saturation process were recorded by volumetric soil moisture content sensors. The results of model tests show that failures of the model slopes were essentially initiated by the development of an unstable area near the slope toe, upon the formation of the seepage area, with shallow noncircular sliding being the dominant failure mode. The volumetric moisture content of the slope region where localized failures initiated was noted to reach a nearly saturated value. However, the major portion of soil slopes involved in overall instability was still in an unsaturated condition. Based on the observed moisture content response of the model slopes, a concept for prediction methodology of rainfall-induced slope failures is introduced.  相似文献   
13.
A method to analyze in vivo metabolites in blood obtained from the hepatic vein after the intraportal injection of a drug was established. This method includes cannulation into the portal vein, hepatic vein and bile duct, followed by TLC-autoradioluminography of a non-extracted sample. Either [14C]diazepam, L-3,4-dihydroxyphenyL[3-(14)C]alanine or [14C]inulin was administered on the day following the surgical operation to avoid the influence of anesthesia. Radioactive concentrations of [14C]DOPA decreased rapidly in the first 1 min, then decreased gradually. The concentrations of [14C]diazepam increased within the first 1 min and then decreased gradually. The concentration of [14C]inulin was approximately 10 times higher than that of [14C]DOPA, and both decreased gradually. These results show that the uptake levels of the drugs to the liver varied depending on the drugs. The metabolites of [14C]diazepam and [14C]DOPA were detected as early as 5 s after administration. These results suggest that the in vivo hepatic first pass effect of drugs in the early period of injection (5 s) can be studied using these techniques.  相似文献   
14.
15.
Long terminal repeats of feline leukemia viruses cloned from feline acute myeloid leukemias frequently contained direct repeats of 40 to 74 bp in the upstream region of the enhancer (URE). The repetitive URE conferred an enhancer function upon gene expression in myeloid cells, suggesting its association with tumorigenic potential in myeloid cells.  相似文献   
16.
In this paper, a new method for secure remote biometric authentication preventing the vulnerability of compromised biometrics is presented. The idea is based on a public-key cryptographical protocol, referred as zero-knowledge proof, which allows a user to prove that she has surely a valid biometric data without revealing the data. Hence, the scheme is free from the risk of disclosure of biometric data. Even if a malicious administrator has a privilege access to the private database, it is infeasible for him to learn the private template. This paper studies two well-known definitions, the cosine correlation and the Euclidean distance as similarities of given two feature vectors. Both similarities are defined with some multiplications and additions, which can be performed in privacy-preserving way because of the useful property of public-key commitment scheme, additive homomorphism. The estimation based on the experimental implementation shows that the private Euclidean distance scheme archives better accuracy in terms of false acceptance and rejection than the private cosine coloration scheme, but it requires about $5/2 n \ell$ overhead to evaluate $n$ -dimension feature vectors consisting of $\ell$ -bit integers.  相似文献   
17.
The flow control of NaCl aqueous solution was examined by applying gas-liquid interface deformation induced by magnetic fields. Detailed studies of the dependence of flow velocity and concentration on the change in flow rate were carried out. In this experiment, with a flow on the order of 100 ml/min, the change in flow rate was measured under magnetic fields of up to 10 T. The flow rate decreased due to gas-liquid interface deformation at magnetic fields of about 6 T or more; the decrease in flow rate was approximately 23% at most. The change in flow rate was dependent on the flow velocity but not on the concentration. In addition, the possibility of using gas-liquid interface deformation induced by magnetic fields as a new means of controlling the flow of NaCl solution without contact was discussed.  相似文献   
18.
Floods are a common feature in rapidly urbanizing Dhaka and its adjoining areas. Though Greater Dhaka experiences flood almost in every year, flood management policies are mostly based on structural options including flood walls, dykes, embankments etc. Many shortcomings of the existing flood management systems are reported in numerous literatures. The objective of this paper is to assess flood hazard in Greater Dhaka for the historical flood event of 1998 using Synthetic Aperture Radar (SAR) data with GIS data. Flood-affected frequency and flood depth calculated from the multi-date SAR imageries were used as hydrologic parameters. Elevation heights, land cover classification, geomorphic division and drainage network data generated from optical remote sensing and analogue maps were used through GIS approach. Using a ranking matrix in three dimensional multiplication mode, flood hazard was assessed. All possible combination of flood hazard maps was prepared using land-cover, geomorphology and elevation heights for flood-affected frequency and floodwater depth. Using two hazard maps which produced the highest congruence for flood frequency and flood depth, a new flood hazard map was developed by considering the interactive effect of flood-affected frequency and floodwater depth, simultaneously. This new hazard map can provide more safety for flood countermeasures because pixels belonging to higher hazard degrees were increased due to the consideration of higher degrees of ranks. The estimation of flood hazard areas revealed that a major portion of Greater Dhaka comprised moderate to very high hazard zone. Only a little portion (8.04%) was found to be the least vulnerable to potential flood hazard. Conversely, 28.70% of Greater Dhaka was found within very high hazard zone. Based on this study, comprehensive flood hazard management strategies for land use planning decision were proposed for the efficient management of future flood disasters.  相似文献   
19.
The concentration of polycyclic aromatic hydrocarbons (PAHs) was measured in the sediment, a bivalve (Mactra veneriformis), fecal materials (feces and pseudofeces) of M. veneriformis, and excrement (feces) of an annelid (Marphysa sanguinea), which were collected in the Yoro tidal flat in Chiba, Japan. The total PAH concentration was 350 μg/kg-dry in the fecal materials of M. veneriformis and 977 μg/kg-dry in the excrement of M. sanguinea; these values were about 8–23 times as large as that of the sediment. The concentration of the fecal materials stayed constant even after 24 h, whereas that of the excrement decreased to half in 2 h. The sediment and fecal materials of M. veneriformis showed a high level of PAHs with lower molecular weight such as phenanthrene, fluoranthene, and pyrene; on the other hand, the excrement of M. sanguinea showed a high level of PAHs with higher molecular weight such as chrysene, benzo[b]fluoranthene, benzo[a]pyrene, and perylene. The logarithm of the concentration factor, defined as the ratio of the concentration of individual PAHs in the fecal materials or excrement to that in the sediment, correlated with the logarithm of the n-octanol/water partition coefficient for the PAHs (R 2 = 0.803). These findings indicate that the sources and characteristics of the fecal materials of M. veneriformis and the excrement of M. sanguinea are different.  相似文献   
20.
Mesoporous silica MCM-41, especially an Al-containing one, showed high catalytic activity for synthesis of methyl N-phenyl carbamate from dimethyl carbonate and aniline at 363-383 K. It was easily separated from the product solution, and the catalyst was able to be used repeatedly.  相似文献   
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