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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   
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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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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   
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Estimation of the direct radiative forcing (DRF) by atmospheric particles is uncertain to a large extent owing to uncertainties in their morphology (shape and size), mixing states, and chemical composition. A region-specific database of the aforementioned physico-chemical properties (at individual particle level) is necessary to improve numerically-estimated optical and radiative properties. Till date, there is no detailed observation of the above mentioned properties over Kanpur in the Indo-Gangetic Plain (IGP). To fill this gap, an experiment was carried out at Kanpur (IITK; 26.52°N, 80.23°E, 142 m msl), India from April to July, 2011. Particle types broadly classified as (a) Cu-rich particles mixed with carbon and sulphur (b) dust and clays mixed with carbonaceous species (c) Fe-rich particles mixed with carbon and sulfur and (d) calcite (CaCO3) particles aged with nitrate, were observed. The frequency distributions of aspect ratio (AR; indicator of extent of particle non-sphericity) of total 708 particles from April to June reveal that particles with aspect ratio range >1.2 to ≤1.4 were abundant throughout the experiment except during June when it was found to shift to high AR range, >1.4 to ≤1.6 (followed with another peak of AR i.e. >2 to ≤2.4) due to dust storm conditions enhancing the occurrence of more non-spherical particles over the sampling site. The spherical particles (and close to spherical shape; AR range, 1.0 to ≤1.2) were found to be <20% throughout the experiment with a minimum (11.5%) during June. Consideration of Homogeneous Equivalent Sphere Approximation (HESA) in the optical/radiative model over the study region is found to be irrelevant during the campaign.  相似文献   
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Deepika  Hukum Singh 《Mapan》2018,33(2):165-168
The present paper aims at the study of size distribution of particles in nanostructured Se58Ge39Pb3 glass using X-ray diffraction (XRD), Transmission electron microscopy (TEM) and UV–visible spectrophotometer. The thin film sample has been prepared using melt quenching technique and inert gas consolidation method. The particle size distribution obtained from XRD and UV–Vis spectrophotometer shows more uncertainty than the results obtained from TEM measurements. The absorption spectra recorded on UV–Vis spectrophotometer is employed to get band gap values corresponding to different size distribution in sample. Further, it is concluded that TEM is the best measurement technique for size distribution as it has less uncertainty in the obtained results.  相似文献   
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Prediction of the in vivo performance of the drug product from the in vitro studies is the major challenging job for the pharmaceutical industries. From the current regulatory perspective, biorelevant dissolution media should now be considered as quality control media in order to avoid the risk associated. Physiological based pharmacokinetic models (PBPK) coupled with biorelevant dissolution medium is widely used in simulation and prediction of the plasma drug concentration and in vivo drug performance. The present investigation deals with the evaluation of biorelevant dissolution media as well as in vivo drug performance by PBPK modelling using STELLA® simulation software. The PBPK model was developed using STELLA® using dissolution kinetics, solubility, standard gastrointestinal parameters and post-absorptive disposition parameters. The drug product selected for the present study includes Linezolid film-coated immediate-release tablets (Zyvox), Tacrolimus prolonged-release capsules (Advagraf), Valganciclovir tablets (Valcyte) and Mesalamine controlled-release capsules (Pentasa) each belonging to different biopharmaceutics classification system (BCS). The simulated plasma drug concentration was analyzed and pharmacokinetic parameters were calculated and compared with the reported values. The result from the present investigation indicates that STELLA® when coupled with biorelevant dissolution media can predict the in vivo performance of the drug product with prediction error less than 20% irrespective of the dosage form (immediate release versus modified release) and BCS Classification. Thus, STELLA® can be used for in vivo drug prediction which will be helpful in generic drug development.  相似文献   
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The aim of this study was to investigate the production of biogenic amines (BA), histamine and tyramine by some probiotic lactic acid bacteria (LAB). Fifteen strains representing six LAB species were screened qualitatively by growing them in a decarboxylase medium. Quantitative analysis was carried out by HPLC analysis with direct derivatization of acid extracts. Lactobacillus casei (TISTR 389) and Lactobacillus delbrueckii subsp. bulgaricus (TISTR 895) were found to produce BA. The highest levels of histamine (1820.9 ± 3.5 mg L?1) and tyramine (5486.99 ± 47.6 mg L?1) formation were observed for the TISTR 389 strain, while TISTR 895 produced only histamine (459.1 ± 0.63 mg L?1) in the decarboxylase broth. Biogenic amine potential was not observed for the Lactobacillus acidophilus, Lactobacillus lactis subsp. lactis, Lactococcus lactis subsp. lactis, and Lactobacillus plantarum strains studied. This study confirmed that BA formation is strain dependent and not related to the species. Therefore, careful screening for amino acid decarboxylase activity is recommended before selecting LAB as appropriate starter or probiotic strains in food and dairy industry.  相似文献   
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