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41.
Zachary H. Levine Benjamin R. Galloway Adele P. Peskin 《Journal of research of the National Institute of Standards and Technology》2011,116(3):685-688
RECIST (Response Evaluation Criteria in Solid Tumors) is a linear measure intended to predict tumor size in medical computed tomography (CT). In this work, using purely geometrical considerations, we estimate how well RECIST can predict the volume of randomly-oriented tumor models, each composed of the union of ellipsoids. The principal conclusion is that RECIST is likely to work less well for realistic tumors than for ellipsoids. 相似文献
42.
Isolation of red wine components with anti-adhesion and anti-biofilm activity against Streptococcus mutans 总被引:1,自引:0,他引:1
Maria Daglia Monica Stauder Adele Papetti Caterina Signoretto Giovanni Giusto Pietro Canepari Carla Pruzzo Gabriella Gazzani 《Food chemistry》2010
Red wine is a widely consumed beverage with multiple beneficial effects on human health. In the present paper, the anticaries properties of red wine were studied in vitro and ex vivo. Our in vitro findings shows that dealcoholised red wine, besides exerting antibacterial activity, strongly interferes with Streptococcus mutans adhesion to saliva-coated hydroxyapatite (sHA) beads, promotes its detachment from sHA, and powerfully inhibits in vitro biofilm formation. The main components responsible for such activities were found to be proanthocyanidins. The ability of red wine to inhibit ex vivoS. mutans biofilm formation on the occlusal surface of natural human teeth also was demonstrated. 相似文献
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44.
Adriano da Silva Éliton Fontana Viviana Cocco Mariani Francisco Marcondes 《International Journal of Heat and Mass Transfer》2012,55(23-24):6808-6818
Natural convection in trapezoidal cavities, especially those with two internal baffles in conjunction with an insulated floor, inclined top surface, and isothermal left-heated and isothermal right-cooled vertical walls, has been investigated numerically using the Element based Finite Volume Method (EbFVM). In numerical simulations, the effect of three inclination angles of the upper surface as well as the effect of the Rayleigh number (Ra), the Prandtl number (Pr), and the baffle’s height (Hb) on the stream functions, temperature profiles, and local and average Nusselt numbers has been investigated. A parametric study was performed for a wide range of Ra numbers (103 ? Ra ? 106) Hb heights (Hb = H1/3, 2H1/3, and H1), Pr numbers (Pr = 0.7, 10 and 130), and top angle (θ) ranges from 10 to 20. A correlation for the average Nusselt number in terms of Pr and Ra numbers, and the inclination of the upper surface of the cavity is proposed for each baffle height investigated. 相似文献
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Hull cells are often used to determine the optimum current density range for industrial electroplating. However, these cells do not reproduce correctly the hydrodynamic conditions. The design and the use of a modified Hull cell able to reproduce constant hydrodynamic conditions at the cathode for a large range of circulation speeds are described. Mass transfer and current distribution at the cathode have been evaluated in this cell for copper and zinc deposition. 相似文献
48.
1. Nitric oxide (NO) synthase activity was studied in slices of human temporal cortex samples obtained in neurosurgery by measuring the conversion of L-[3H]-arginine to L-[3H]-citrulline. 2. Elevation of extracellular K+ to 20, 35 or 60 mM concentration-dependently augmented L-[3H]-citrulline production. The response to 35 mM KCl was abolished by N(G)-nitro-L-arginine (100 microM) demonstrating NO synthase specific conversion of L-arginine to L-citrulline. Increasing extracellular MgCl2 concentration up to 10 mM also prevented the K+ (35 mM)-induced NO synthase activation, suggesting the absolute requirement of external calcium ions for enzyme activity. 3. However, the effect of high K+ (35 mM) on citrulline synthesis was insensitive to the antagonists of ionotropic and metabotropic glutamate receptors dizocilpine (MK-801), 6-nitro-7-sulphamoylbenzo(f)-quinoxaline-2-3-dione (NBQX) or L-2-amino-3-phosphonopropionic acid (L-AP3) as well as to the nicotinic receptor antagonist, mecamylamine. 4. The 35 mM K+ response was insensitive to omega-conotoxin GVIA (1 microM) and nifedipine (100 microM), but could be prevented in part by omega-agatoxin IVA (0.1 and 1 microM). The inhibition caused by 0.1 microM omega-agatoxin IVA (approximately 30%) was enhanced by adding omega-conotoxin GVIA (1 microM) or nifedipine (100 microM). Further inhibition (up to above 70%) could be observed when the three Ca2+ channel blockers were added together. Similarly, synthetic FTX 3.3 arginine polyamine (sFTX) prevented (50% at 100 microM) the K+-evoked NO synthase activation. This effect of sFTX was further enhanced (up to 70%) by adding 1 microM omega-conotoxin GVIA plus 100 microM nifedipine. No further inhibition could be observed upon addition of MK-801 or/and NBQX. 5. It was concluded that elevation of extracellular [K+] causes NO synthase activation by external Ca2+ entering cells mainly through channels of the P/Q-type. Other Ca2+ channels (L- and N-type) appear to contribute when P/Q-channels are blocked. 相似文献
49.
Active and passive mode locking has been observed in an erbium doped fibre single ring laser. Pulse durations as short as 100 fs at a repetition rate of 300 GHz have been measured from an erbium doped fibre amplification stage placed at the output of the fibre ring. The ultrafast regime depends critically on the dynamical evolution of the light polarisation along the cavity.<> 相似文献
50.
Carminna Ottone Vivian Farías Rivera Marco Fontana Katarzyna Bejtka Barbara Onida Valentina Cauda 《材料科学技术学报》2014,30(12):1167-1173
Highly mesoporous Zn O and g-Al2O3nanowires(NWs) are both synthesized by a hydrothermal method using commercially available porous anodic aluminium oxide(AAO) as template. AAO membrane acts as template for Zn O NWs and both as template and precursor for g-Al2O3 NWs. The formation of intermediate phases of porous Zn6Al2(OH)16CO3and boehmite(g-Al OOH) were observed, both occurring during the hydrothermal synthesis of porous Zn O and g-Al2O3 NWs, respectively, and disappearing after annealing at 600 C. This novel template-assisted hydrothermal process leads to the formation of porous Zn O and g-Al2O3NWs(specific surface area of 192 m2 g 1and 263 m2 g 1, respectively), showing pore sizes around 4 nm in diameter. The influence of the reaction parameters on the nanostructure morphology was also investigated. A Zn O seed layer, deposited on the AAO channels prior to the hydrothermal synthesis, leads to more compact Zn O nanowires(99 m2 g-1) protecting the AAO host from the chemical attack of the precursor solution. 相似文献