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971.
M. V. Srinivasan 《Biological cybernetics》1994,71(5):401-415
A technique for measuring the motion of a rigid, textured plane in the frontoparallel plane is developed and tested on synthetic
and real image sequences. The parameters of motion – translation in two dimensions, and rotation about a previously unspecified
axis perpendicular to the plane – are computed by a single-stage, non-iterative process which interpolates the position of
the moving image with respect to a set of reference images. The method can be extended to measure additional parameters of
motion, such as expansion or shear. Advantages of the technique are that it does not require tracking of features, measurement
of local image velocities or computation of high-order spatial or temporal derivatives of the image. The technique is robust
to noise, and it offers a simple, novel way of tackling the ‘aperture’ problem. An application to the computation of robot
egomotion is also described.
Received: 3 September 1993/Accepted in revised form: 16 April 1994 相似文献
972.
973.
When humans wish to move sideways, they almost never walk sideways, except for a step or two; they usually turn and walk facing forward. Here, we show that the experimental metabolic cost of walking sideways, per unit distance, is over three times that of forward walking. We explain this high metabolic cost with a simple mathematical model; sideways walking is expensive because it involves repeated starting and stopping. When walking sideways, our subjects preferred a low natural speed, averaging 0.575 m s−1 (0.123 s.d.). Even with no prior practice, this preferred sideways walking speed is close to the metabolically optimal speed, averaging 0.610 m s−1 (0.064 s.d.). Subjects were within 2.4% of their optimal metabolic cost per distance. Thus, we argue that sideways walking is avoided because it is expensive and slow, and it is slow because the optimal speed is low, not because humans cannot move sideways fast. 相似文献
974.
975.
Two strains PB196T and PB62T of Gram-negative, non-motile, and non-spore-forming bacteria, were isolated from soil in South Korea and characterized to
determine their taxonomic positions. 16S rRNA gene sequence analysis showed that the two strains belonged to the genus Sphingomonas. The highest degree of sequence similarity of strain PB196T was found with PB62T (98.9%), Sphingomonas humi PB323T (98.9%), Sphingomonas kaistensis PB56T (98.2%), and Sphingomonas astaxanthinifaciens TDMA-17T (98.0%). The highest degree of sequence similarity of strain PB62T was found with Sphingomonas humi PB323T (98.8%), Sphingomonas astaxanthinifaciens TDMA-17T (98.2%), and Sphingomonas kaistensis PB56T (98.1%). Chemotaxonomic data revealed that they possessed ubiquinone-10 (Q-10) as common in the genus Sphingomonas, that the predominant fatty acids were summed feature 7 (C18:1
ω7c/ω9t/ω12t), summed feature 4 (C16:1
ω7c/C15:0 iso 2OH), C16:0, and C17:1
ω6c, and that they contained sphingoglycolipid, phosphatidylglycerol (PG), and phosphatidyle-thanolamine (PE) in common but they
showed difference for diphosphatidylglycerol (DPG). Based on these data, PB196T (=KCTC 12339T =JCM 16604T) and PB62T (=KCTC 12336T =JCM 16605T =KEMB 9004-005T) should be classified as type strains of two novel species, for which the names Sphingomonas rosea sp. nov. and Sphingomonas swuensis sp. nov. are proposed, respectively. 相似文献
976.
Strain BS12T, a Gram-negative motile bacterium, was isolated from soil in South Korea and characterized to determine its taxonomic position.
Phylogenetic analyses based on the 16S rRNA gene sequence revealed that the strain belonged to the family Alcaligenaceae in the class Betaproteobacteria. The highest degree of sequence similarities of strain BS12T were found with Pigmentiphaga litoralis JSM 061001T (98.3%), Pigmentiphaga daeguensis K110T (98.2%), and Pigmentiphaga kullae K24T (98.1%). Chemotaxonomic data revealed that strain BS12T possessed ubiquinone-8, which is common in the family Alcaligenaceae, and the predominant fatty acids were C16:0, C17:0 cyclo, summed feature 3 (C16:1
ω6c/ω7c), and summed feature 8 (C18:1
ω6c/ω7c). The major polar lipids of strain BS12T were phosphatidylethanolamine and phosphatidylglycerol. Based on these data, BS12T (=KCTC 23577T =JCM 17666T =KEMB 9004-082T) should be classified as a type strain of a novel species, for which the name Pigmentiphaga soli sp. nov. is proposed. 相似文献
977.
978.
Large-scale transcriptome analysis in chickpea (Cicer arietinum L.), an orphan legume crop of the semi-arid tropics of Asia and Africa 总被引:1,自引:0,他引:1
979.
Yadav S Tomar AK Jithesh O Khan MA Yadav RN Srinivasan A Singh TP Yadav S 《The protein journal》2011,30(8):575-580
The watermelon (Citrullus lanatus) seeds are highly nutritive and contain large amount of proteins and many beneficial minerals such as magnesium, calcium,
potassium, iron, phosphorous, zinc etc. In various parts of the world, C. lanatus seed extracts are used to cure cancer, cardiovascular diseases, hypertension, and blood pressure. C. lanatus seed extracts are also used as home remedy for edema and urinary tract problems. In this study, we isolated protein fraction
of C. lanatus seeds using various protein separation methods. We successfully purified a low molecular weight vicilin-like glycoprotein
using chromatographic methods followed by SDS-PAGE and MALDI-TOF/MS identification. This is the first report of purification
of a vicilin like polypeptide from C. lanatus seeds. In next step, we extracted mRNA from immature seeds and reverse transcribed it using suitable forward and reverse
primers for purified glycoprotein. The PCR product was analysed on 1% agarose gel and was subsequently sequenced by Dideoxy
DNA sequencing method. An amino acid translation of the gene is in agreement with amino acid sequences of the identified peptides. 相似文献
980.
Kumar AK Sudha V Srinivasan R Ramachandran G 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2011,879(30):3663-3667
A high performance liquid chromatographic method for determination of moxifloxacin in human saliva was developed. The method involved deproteinisation of the sample with perchloric acid and analysis of the supernatant using a reversed-phase C18 column (150 mm) and fluorescence detection at an excitation wavelength of 290 nm and an emission wavelength of 460 nm. The assay was specific for moxifloxacin and linear from 0.25 to 10.0 μg/ml. The relative standard deviation of intra- and inter-day assays was lower than 10%. The average recovery of moxifloxacin from saliva was 101%. Due to its simplicity, the assay can be used for pharmacokinetic studies of moxifloxacin. 相似文献