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991.
992.
Pasquale Catalano Francesco Caponio 《European Journal of Lipid Science and Technology》1996,98(12):408-412
Polyphenolic substances enhance the resistance to oxidation of virgin olive oils, but an excess of polyphenols determines a marked bitter, somewhat tannic taste of the oil, similar to the taste of unripe olives. Tests have been carried out on drupes of different cultivars in industrial productions to evaluate the effect of the machines used to prepare olive pastes on the contents of polyphenols in the oils. Notably greater amounts of polyphenols were found in the oils extracted from hammer-crushed pastes than in the oils extracted from milled pastes. The kneading process which follows, especially if it is long, often reduces the amounts of total polyphenols. Therefore, in order to obtain the best organoleptic and chemical quality in extra virgin olive oils, two systems are suggested for the processing procedures. For olives of certain cultivars (Coratina) and for not-blackened or slightly blackened drupes yielding oils with a very high content of total polyphenols, it is most expedient to use the stone-mill together with a kneader system. But it is more suitable to utilize the hammercrusher together with a kneader system in processing olives (such as the Ogiiarola Salentina or Leccino cultivars) yielding normally “sweet” oils with a low content of total polyphenols. 相似文献
993.
Francesco Centurelli Alberto Di Martino Giuseppe Scotti Pasquale Tommasino Alessandro Trifiletti 《国际射频与微波计算机辅助工程杂志》2003,13(5):348-356
A new statistical nonlinear model of GaAs FET MMICs which allows the representation of distance‐dependent technological parameter variations by means of equivalent circuit parameters, and an automatic extraction procedure, are presented. The capability to reproduce statistical distribution has been successfully checked on S parameters at different distances in the 1–50 GHz frequency range. © 2003 Wiley Periodicals, Inc. Int J RF and Microwave CAE 13, 348–356, 2003. 相似文献
994.
The objective of the present study was to identify p24 antigenic domains recognized during natural human immunodeficiency virus type 1 (HIV-1) infection, the determination of the major epitopes of p24 having significant applications for both the improvement of diagnostic approaches and the development of vaccines. Reactivity of 20 HIV-1-infected patients and 8 HIV-1-negative patients was analyzed using an enzyme-linked immunosorbent assay (ELISA) developed with 45 overlapping synthetic pentadecapeptides, spanning amino acids 133 to 363 of HIV-1 p55gag precursor. Two peptides covering aa 178-192 and 288-302 of p55 were recognized by 40 and 45% of HIV-1 antibody-positive human samples, respectively. A peptide covering aa 272-322 of p55 was synthesized and recognized by most human sera in indirect ELISA. However, inhibition assays indicated that this sequence does not contain all of the immunodominant domains of p24 since it was not sufficient to block binding of human sera to whole p24. A three-dimensional model of p24 derived from the Mengovirus VP2 suggests that the two distant sequences recognized by human sera containing antibodies to HIV-1 could possibly be a part of a conformational epitope built up by two loops corresponding to aa 183-186 and 289-292. 相似文献
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996.
Specific ligands (aptamers) for angiogenin were selected from a 72-mer oligodeoxynucleotide library consisting of 28 randomized positions flanked by two constant regions of 22 residues each. From a starting pool of approximately 10(14) molecules, 19 angiogenin-binding ligands were obtained. Among them, two oligonucleotides showed significant inhibition of the ribonucleolytic activity of angiogenin with apparent Kis of 0.65 and 0.60 micro M, respectively. One of them was shortened on the basis of its secondary structure to provide a 45-mer oligonucleotide that retained much of the inhibitory properties of the parent molecule. It inhibits both the angiogenic and cell proliferative activities of angiogenin but does not interfere with its nuclear translocation in human endothelial cells. Importantly, the inhibitor is cotranslocated to the nucleus with angiogenin in a approximately 1:1 stoichiometric ratio. These results demonstrate that the inhibition of angiogenin-induced cell proliferation and angiogenesis by the oligonucleotide is due to suppression of the ribonucleolytic activity of angiogenin, an event that occurs most likely within the cell nucleus. 相似文献
997.
Recent advances in fuzzy techniques for image enhancement 总被引:4,自引:0,他引:4
Enhancement of noisy image data is a very challenging issue in many research and application areas. In the last few years, nonlinear filters based on fuzzy models have been shown to be very effective in removing noise without destroying the useful information contained in the image data. The aim of this paper is to provide a comprehensive overview of most significant methods in the literature and to present some new advances in the field of evolutionary neural fuzzy filters 相似文献
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999.
1000.
The huge amount of wastes produced by modern and developed countries involves important aspects of economical, social and technical fields and also of the environment. For this reason, different technologies have been proposed for trying to reduce the impact of waste management and disposal. Generally waste management system consists of different steps like selective collection, recycling and reuse operation, energy recovery from waste and landfilling. A new technology proposed for thermal waste treatment is the plasma pyrolysis vetrification (PPV). This system seems to have interesting perspective due to the possibility of thermal treatment of dangerous slag or waste producing inactivate vetrified substances that can be landfilled or used as building materials with no impact on the environment. In this study, the effect of the application of a PPV plant on an existing waste management system was evaluated with a life cycle assessment (LCA) analysis. All the activities connected to the existing system have been carefully analysed by collecting a large quantity of experimental data. Some assumptions have been made, in particular, on the PPV plant performance. LCA analysis results illustrate how the environmental benefits arising from the adoption of the new technology, concerns only few aspects of the whole system. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献