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排序方式: 共有464条查询结果,搜索用时 31 毫秒
1.
Deepika M. Malini Raajan N. R. Srinivasan A. 《Multimedia Tools and Applications》2022,81(9):12701-12724
Multimedia Tools and Applications - The three-dimensional models of brain tumors serve as diagnostic assistance for physicians, surgeons, and radiologists. The proposed system establishes an... 相似文献
2.
Dr. Kathrin Schindl Dr. Deepika Sharma Prof. Dr. Dieter Spiteller 《Chembiochem : a European journal of chemical biology》2020,21(21):3151-3157
When Streptomyces violaceoruber grows together with Streptomyces sp. MG7-G1, it reacts with strongly induced droplet production on its aerial mycelium. Initially the metabolite profile of droplets from S. violaceoruber in co-culture with Streptomyces sp. MG7-G1 was compared to samples from S. violaceoruber in single-culture by using high-performance liquid chromatography-mass spectrometry (HPLC-MS). Then, the exudate from agar plates of co-cultures and single cultures (after freezing and thawing) was also analysed. Several compounds were only observed when S. violaceoruber was grown in co-culture. Based on their high-resolution ESI mass spectra and their comparable retention times to the calcium-dependent antibiotics (CDAs) produced by S. violaceoruber, the new compounds were suspected to be deacylated calcium-dependent antibiotics (daCDAs), lacking the 2,3-epoxyhexanoyl residue of CDAs. This was verified by detailed analysis of the MS/MS spectra of the daCDAs in comparison to the CDAs. The major CDA compounds present in calcium ion-supplemented agar medium of co-cultures were daCDAs, thus suggesting that Streptomyces sp. MG7-G1 expresses a deacylase that degrades CDAs. 相似文献
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Effect of boron on the low-cycle fatigue behavior and deformation structure of INCONEL 718 at 650 °C
L. Xiao M. C. Chaturvedi D. L. Chen 《Metallurgical and Materials Transactions A》2004,35(11):3477-3487
Symmetrical push-pull low-cycle fatigue (LCF) tests were performed on INCONEL 718 (IN718) containing 12, 29, 60, and 100 ppm
B at 650 °C. The results showed that all the alloys experienced a relatively short period of initial cyclic hardening at low
strain amplitudes, followed by a regime of saturation or slightly continuous cyclic softening. The initial cyclic hardening
phase decreased with increasing strain amplitudes, and disappeared at the high strain amplitudes. A serrated flow was observed
in the plastic regions of cyclic stress-strain hysteresis loops. The saturated cyclic stress amplitude at a given strain amplitude
was highest for the alloy with 60 ppm B, and lowest for the alloy with 12 ppm B. The LCF lifetime increased with increasing
B concentration up to 60 ppm, and then decreased as the B content increased from 60 to 100 ppm. Fractographic analysis suggested
that the fracture mode changed from intergranular to transgranular cracking as the B concentration increased. The characteristic
deformation microstructures produced by LCF tests at 650 °C, examined via transmission electron microscopy, were regularly spaced arrays of planar deformation bands on {111} slip planes in all four
alloys. A ladderlike structure was observed in some local regions in the alloy with 12 ppm B. Heavily deformed planar deformation
bands were observed in the fatigued specimens with 100 ppm B. The mechanism of improvement in the LCF life of IN718 due to
B addition is discussed. 相似文献
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Spina bifida, a congenital deformity of the posterior wall of vertebrae of the spine, is a midline defect of skin, vertebral arches and neural tube, usually in the lumbosacral region. Its incidence is reported to be 0.2 to 0.4 per 1000 live births. Various hypotheses have been put forward as etiological factors for spina bifida including consumption of potato affected by blight and hardness of drinking water but these have not been proven. Two groups of 50 randomly chosen children were established. The study group consisted of children aged 5 to 12 years, weighing 15 to 30 kg, consuming fluoride rich drinking water (4.5 and 8.5 ppm fluoride; WHO permissible limit is 1.5 ppm fluoride), and manifesting either clinical, dental and/or skeletal fluorosis. The control group consisted of age and weight-matched children, consuming less than or equal to 1.5 ppm fluoride in drinking water and not showing any evidence of fluoride toxicity. These children were evaluated for antenatal history, general clinical examination (especially for dimples, tufts of hair, haemangioma on skin throughout the length of spine), other congenital abnormalities, evidence of fluoride toxicity, biochemical estimation for fluoride levels in blood and serum and by skiagrams of the spine to examine for the presence of spina bifida occulta. A total of 22 (44%) of the 50 children in group A, the study group, and 6 (12%) of the 50 children in group B, the control group, revealed spina bifida occulta in the lumbosacral region.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
9.
S. Chaturvedi C. Dunne Z. Ashktorab R. Zachariah B. Shneiderman 《Computer Graphics Forum》2014,33(8):52-68
An important part of network analysis is understanding community structures like topological clusters and attribute‐based groups. Standard approaches for showing communities using colour, shape, rectangular bounding boxes, convex hulls or force‐directed layout algorithms remain valuable, however our Group‐in‐a‐Box meta‐layouts add a fresh strategy for presenting community membership, internal structure and inter‐cluster relationships. This paper extends the basic Group‐in‐a‐Box meta‐layout, which uses a Treemap substrate of rectangular regions whose size is proportional to community size. When there are numerous inter‐community relationships, the proposed extensions help users view them more clearly: (1) the Croissant–Doughnut meta‐layout applies empirically determined rules for box arrangement to improve space utilization while still showing inter‐community relationships, and (2) the Force‐Directed layout arranges community boxes based on their aggregate ties at the cost of additional space. Our free and open source reference implementation in NodeXL includes heuristics to choose what we have found to be the preferable Group‐in‐a‐Box meta‐layout to show networks with varying numbers or sizes of communities. Case study examples, a pilot comparative user preference study (nine participants), and a readability measure‐based evaluation of 309 Twitter networks demonstrate the utility of the proposed meta‐layouts. 相似文献
10.
Stefano Cozzini Deepika Vaddi Savita Goel Francesco De Giorgi S. K. Dash 《Journal of Grid Computing》2014,12(2):303-320
In this paper, we present a possible approach to use different Grid infrastructures across Europe and India for regional climate simulations and discuss in details the advantages and limitations in using them. The application taken into consideration is the Regional Climate Model RegCM4, which has been recently re-written for making it more efficient and easier to be fully exploited on any kind of computational infrastructure. We describe here the methods applied to port this package on the Grid infrastructures made available by the EU-IndiaGrid project. We also discuss different approaches, the way to run the model on both European and Indian infrastructures and our promising approach to deal with data management issues. Use of RegCM on Grid infrastructure has further been compared with that on HPC resources. The domain worked upon for these tests is the South-Asia CORDEX domain, which is of great importance for the Indian Summer Monsoon. Our final conclusion is that, for certain class of experiments, RegCM4 model can be efficiently and easily integrated on Grid infrastructures, by means of the procedures described in this paper. 相似文献