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71.
We analyze in detail the apparent violation of the reciprocity law that occurs for an interline CCD array owing to its responsivity that varies with exposure time, and we investigate other parameters having an influence on this variation, such as the numerical aperture of the system or the illumination wavelength. The variation can be explained from a qualitative point of view by the charge leakage that occurs from the sense region to the register region during readout time. This change of the responsivity can be avoided either by using a synchronized external shutter or by limiting the numerical aperture while keeping relatively high exposure times. A detailed characterization for each particular CCD model must be carried out if it is to be employed in low-uncertainty radiometric measurements. 相似文献
72.
73.
Gustavo A. Gonzalez-Aguilar Jorge Celis Rogelio R. Sotelo-Mundo Laura A. de la Rosa Joaquin Rodrigo-Garcia & Emilio Alvarez-Parrilla 《International Journal of Food Science & Technology》2008,43(1):91-101
Treatments to inhibit browning, decay and to extend shelf life of ‘Keitt’, ‘Kent’ and ‘Ataulfo’ mango cultivars as a fresh‐cut produce were investigated. Combinations of calcium chloride (CaCl2), antioxidants [ascorbic acid (AA), citric acid (CA)] and two commercial film coatings resulted in a reduction of browning and deterioration of fresh‐cut mangoes stored at 5 °C, especially for the Ataulfo cultivar. The use of CaCl2 + AA + CA significantly reduced colour deterioration, loss of firmness and did not affect sensory characteristics of fresh‐cut mango, with a larger effect in the Ataulfo cultivar. In general, these treatments prevented loss of sugar and vitamin C of cubes during storage at 5 °C. Shelf life of this cultivar was 21 days, while that of Keitt and Kent was only 9 and 12 days, respectively. There is a correlation between carotene and vitamin C content of Ataulfo mango and its longer shelf life compared with the other cultivars. 相似文献
74.
Jose Luis Amorós Arnaldo Moreno Encarna Blasco Joaquin Javier Pérez Sandra Navarro Sandra Reverter 《International Journal of Applied Ceramic Technology》2019,16(6):2153-2160
Inkjet technology has become very popular in recent years and is nowadays widely used for decorating ceramic products. This has led to in-depth study of the operating principles and process variables involved. These notably influence the properties of the deposited ink layers, as do the physicochemical properties of the applied inks and of the glazes on which the inks are deposited. The problems associated with these factors are further heightened when inks with complex formulations designed to obtain special effects and specific surface properties are used. This study examines the characteristics of the interface that developed on applying an ink on a certain type of glaze, as well as the surface properties of the final product. The relationship of the amount of ink applied per unit area and the particle size distribution (PSD) of the glaze on which it was deposited to ink penetration into the glaze layer was also investigated. The resulting microstructures were observed by SEM, while the variation of glaze layer composition with distance to the surface was determined by SEM-EDS. The results obtained were successfully correlated with the porous texture of the unfired glaze (determined by SEM and mercury porosimetry) and with unfired glaze PSD. 相似文献
75.
Joaquin Vanschoren Hendrik Blockeel Bernhard Pfahringer Geoffrey Holmes 《Machine Learning》2012,87(2):127-158
Thousands of machine learning research papers contain extensive experimental comparisons. However, the details of those experiments
are often lost after publication, making it impossible to reuse these experiments in further research, or reproduce them to
verify the claims made. In this paper, we present a collaboration framework designed to easily share machine learning experiments
with the community, and automatically organize them in public databases. This enables immediate reuse of experiments for subsequent,
possibly much broader investigation and offers faster and more thorough analysis based on a large set of varied results. We
describe how we designed such an experiment database, currently holding over 650,000 classification experiments, and demonstrate
its use by answering a wide range of interesting research questions and by verifying a number of recent studies. 相似文献
76.
In “Why We Need Friendly AI”, Luke Muehlhauser and Nick Bostrom propose that for our species to survive the impending rise of superintelligent AIs, we need to ensure that they would be human-friendly. This discussion note offers a more natural but bleaker outlook: that in the end, if these AIs do arise, they won’t be that friendly.
相似文献77.
Eiichi Wakai Michiyoshi Yamamto Joaquin Molla Takehiko Yokomine Shunhei Nogami 《Fusion Engineering and Design》2011,86(6-8):712-715
The main purpose of present phase of IFMIF/EVEDA (International Fusion Materials Irradiation Facility/Engineering Validation and Engineering Design Activities) is to produce a detailed report of IFMIF engineering design with the integrated design of all facilities in IFMIF. The main function of the IFMIF is to give the demanded design database for the licensing of DEMO reactors and further reactors, and it is achieved from the materials data set obtained from the high, medium, and low flux test modules (HFTM, MFTM and LFTM) of IFMIF. In the evaluation using small specimens, developments and guidelines of small specimen test technique or technology (SSTT) are also demanded for the achievements. This paper is summarized and also analyzed about the design plan status and requirements in these test modules from users, and testing items and test methodology in IFMIF. 相似文献
78.
Laura De Marzi Antonina Monaco Joaquin De Lapuente David Ramos Miquel Borras Mario Di Gioacchino Sandro Santucci Anna Poma 《International journal of molecular sciences》2013,14(2):3065-3077
Owing to their radical scavenging and UV-filtering properties, ceria nanoparticles (CeO2-NPs) are currently used for various applications, including as catalysts in diesel particulate filters. Because of their ability to filter UV light, CeO2-NPs have garnered significant interest in the medical field and, consequently, are poised for use in various applications. The aim of this work was to investigate the effects of short-term (24 h) and long-term (10 days) CeO2-NP exposure to A549, CaCo2 and HepG2 cell lines. Cytotoxicity assays tested CeO2-NPs over a concentration range of 0.5 μg/mL to 5000 μg/mL, whereas genotoxicity assays tested CeO2-NPs over a concentration range of 0.5 μg/mL to 5000 μg/mL. In vitro assays showed almost no short-term exposure toxicity on any of the tested cell lines. Conversely, long-term CeO2-NP exposure proved toxic for all tested cell lines. NP genotoxicity was detectable even at 24-h exposure. HepG2 was the most sensitive cell line overall; however, the A549 line was most sensitive to the lowest concentration tested. Moreover, the results confirmed the ceria nanoparticles’ capacity to protect cells when they are exposed to well-known oxidants such as H2O2. A Comet assay was performed in the presence of both H2O2 and CeO2-NPs. When hydrogen peroxide was maintained at 25 μM, NPs at 0.5 μg/mL, 50 μg/mL, and 500 μg/mL protected the cells from oxidative damage. Thus, the NPs prevented H2O2-induced genotoxic damage. 相似文献
79.
Ana M. González-Paramás Fátima Lopes da SilvaGlenda Macz-Pop Susana González-ManzanoCristina Alcalde-Eon José Joaquin Pérez-AlonsoM.Teresa Escribano-Bailón Julián C. Rivas-GonzaloCelestino Santos-Buelga 《Food chemistry》2006
Pigments resulting from the direct condensation of anthocyanins and flavanols are usually associated with reactions taking place during processing and storage of plant-derived foods and beverages and have been particularly studied in aged red wines. In this paper, small amounts of flavanol–anthocyanin condensed pigments are found in different plant extracts. Structures are suggested for 10 such condensed pigments detected in extracts of strawberry, runner beans, purple corn and grape skins, based on their MSn fragmentation patterns, following analyses by electrospray tandem mass spectrometry. All of them correspond to dimers containing a flavan-3-ol [either (epi)afzelechin, (epi)catechin or (epi)gallocatechin] as the upper unit carbon–carbon linked to a lower anthocyanin unit consisting of different delphinidin, cyanidin, pelargonidin, peonidin or malvidin derivatives. The detection of these pigments in plant extracts may suggest that they are natural pigments and not products exclusively formed during storage and ageing of processed foods and beverages, as was previously assumed. 相似文献
80.
López V Ortiz S Corujo A López P Navas J Moreno R Martínez-Suárez JV 《Journal of food protection》2007,70(6):1513-1517
In surveys conducted on finished product samples from a single poultry processing plant in Spain, Listeria monocytogenes was found in 14 different uncooked products. To track contamination patterns, 77 L. monocytogenes isolates were characterized by PCR-based serotyping, pulsed-field gel electrophoresis (PFGE) restriction analysis, and PCR-based allelic analysis of the virulence gene actA. Serotyping revealed that 12 isolates (15.6%) were of the L. monocytogenes serotype 4b complex (serotype 4b or the closely related serotypes 4d and 4e). A combination of endonucleases AscI and ApaI PFGE patterns yielded 15 different pulsotypes among all 77 tested isolates. All the serotype 4b isolates belonged to one pulsotype. Sequencing of the actA gene confirmed that all serotype 4b isolates corresponded to the same allelic subtype. The subtype was recovered from five product types, but its presence was not correlated with the production line or the date of isolation, suggesting a possible association of this strain with a common ingredient. This traceback investigation established that pork dewlap, an ingredient common to all the products contaminated with this strain, was the most probable source of L. monocytogenes 4b. The same 4b strain was isolated from four samples of pork dewlap from one specific supplier. After replacement of this contaminated ingredient in the fresh products, this strain of L. monocytogenes serotype 4b was not detected. This study confirms the effectiveness of molecular subtyping to control contamination by specific strains of L. monocytogenes and the importance of testing the different ingredients added to the food products. 相似文献