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991.
Julian Fierrez-Aguilar Author Vitae Javier Ortega-Garcia Author Vitae Author Vitae Josef Bigun Author Vitae 《Pattern recognition》2005,38(5):777-779
A novel score-level fusion strategy based on quality measures for multimodal biometric authentication is presented. In the proposed method, the fusion function is adapted every time an authentication claim is performed based on the estimated quality of the sensed biometric signals at this time. Experimental results combining written signatures and quality-labelled fingerprints are reported. The proposed scheme is shown to outperform significantly the fusion approach without considering quality signals. In particular, a relative improvement of approximately 20% is obtained on the publicly available MCYT bimodal database. 相似文献
992.
Julian Fierrez-Aguilar Daniel Garcia-Romero Javier Ortega-Garcia Joaquin Gonzalez-Rodriguez 《Pattern recognition》2005,38(8):1317-1319
A novel score-level fusion strategy based on Bayesian adaptation for user-dependent multimodal biometric authentication is presented. In the proposed method, the fusion function is adapted for each user based on prior information extracted from a pool of users. Experimental results are reported using on-line signature and fingerprint verification subsystems on the MCYT real bimodal database. The proposed scheme outperforms both user-independent and user-dependent standard approaches. As compared to non-adapted user-dependent fusion, relative improvements of 80% and 55% are obtained for small and large training set sizes, respectively. 相似文献
993.
Antonio Plaza Author Vitae Pablo Martinez Author VitaeAuthor Vitae Javier Plaza Author Vitae 《Pattern recognition》2004,37(6):1097-1116
This paper presents a new approach to the analysis of hyperspectral images, a new class of image data that is mainly used in remote sensing applications. The method is based on the generalization of concepts from mathematical morphology to multi-channel imagery. A new vector organization scheme is described, and fundamental morphological vector operations are defined by extension. Theoretical definitions of extended morphological operations are used in the formal definition of the concept of extended morphological profile, which is used for multi-scale analysis of hyperspectral data. This approach is particularly well suited for the analysis of image scenes where most of the pixels collected by the sensor are characterized by their mixed nature, i.e. they are formed by a combination of multiple underlying responses produced by spectrally distinct materials. Experimental results demonstrate the applicability of the proposed technique in mixed pixel analysis of simulated and real hyperspectral data collected by the NASA/Jet Propulsion Laboratory Airborne Visible/Infrared Imaging Spectrometer and the DLR Digital Airborne (DAIS 7915) and Reflective Optics System Imaging Spectrometers. The proposed method works effectively in the presence of noise and low spatial resolution. A quantitative and comparative performance study with regards to other standard hyperspectral analysis methodologies reveals that the combined utilization of spatial and spectral information in the proposed technique produces classification results which are superior to those found by using the spectral information alone. 相似文献
994.
995.
Marta Gmez-Almería Sonia Burgaz Carlos Costas-Insua Carmen Rodríguez-Cueto Irene Santos-García Ignacio Rodríguez-Crespo Concepcin García Manuel Guzmn Eva de Lago Javier Fernndez-Ruiz 《International journal of molecular sciences》2021,22(22)
In the present study, we investigated the involvement of the chaperone protein BiP (also known as GRP78 or Hspa5), a master regulator of intracellular proteostasis, in two mouse models of neurodegenerative diseases: amyotrophic lateral sclerosis (ALS) and Parkinson’s disease (PD). To this end, we used mice bearing partial genetic deletion of the BiP gene (BiP+/− mice), which, for the ALS model, were crossed with mutant SOD1 (mSOD1) transgenic mice to generate mSOD1/BiP+/− double mutant mice. Our data revealed a more intense neurological decline in the double mutants, reflected in a greater deterioration of the neurological score and rotarod performance, with also a reduced animal survival, compared to mSOD1 transgenic mice. Such worsening was associated with higher microglial (labelled with Iba-1 immunostaining) and, to a lesser extent, astroglial (labelled with GFAP immunostaining) immunoreactivities found in the double mutants, but not with a higher loss of spinal motor neurons (labelled with Nissl staining) in the spinal cord. The morphological analysis of Iba-1 and GFAP-positive cells revealed a higher presence of activated cells, characterized by elevated cell body size and shorter processes, in double mutants compared to mSOD1 mice with normal BiP expression. In the case of the PD model, BiP+/− mice were unilaterally lesioned with the parkinsonian neurotoxin 6-hydroxydopamine (6-OHDA). In this case, however, we did not detect a greater susceptibility to damage in mutant mice, as the motor defects caused by 6-OHDA in the pole test and the cylinder rearing test, as well as the losses in tyrosine hydroxylase-containing neurons and the elevated glial reactivity (labelled with CD68 and GFAP immunostaining) detected in the substantia nigra were of similar magnitude in BiP+/− mice compared with wildtype animals. Therefore, our findings support the view that a dysregulation of the protein BiP may contribute to ALS pathogenesis. As BiP has been recently related to cannabinoid type-1 (CB1) receptor function, our work also opens the door to future studies on a possible link between BiP and the neuroprotective effects of cannabinoids that have been widely reported in this neuropathological context. In support of this possibility, preliminary data indicate that CB1 receptor levels are significantly reduced in mSOD1 mice having partial deletion of BiP gene. 相似文献
996.
Elena Ibez Javier Tabera Elena Ramos Sara Lpez‐Sebastin Guillermo Reglero 《Journal of the science of food and agriculture》1999,79(10):1275-1279
A method for the analysis of fruit headspace using a programmed temperature vaporiser (PTV) gas chromatographic injector as an intermediate trap is proposed. The method consists of a purge of the volatile compounds into the PTV glass‐liner filled with a packing material of high surface area. The trapped compounds are thermally desorbed in the PTV injector and transferred to the gas chromatographic column. The variables that influence the extraction and transfer processes have been optimised for fruit flavour analysis. Examples of the application of the method to the analysis of bananas, blackberries and raspberries are given. © 1999 Society of Chemical Industry 相似文献
997.
Ana Elías Astrid Barona Javier Ormazabal Gabriel Ibarra Javier Caamano 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1999,74(10):949-956
The selection of a suitable sludge which will be the inoculum of the reactor is the first step in the start‐up procedure of an anaerobic reactor. The sludge selected (inoculum) for this study was obtained from a UASB (Up‐flow Anaerobic Sludge Bed) reactor used for the treatment of alcohol industry wastewaters. The industrial sludge was used in this work as the inoculum of two laboratory‐scale UASB anaerobic reactors, which were fed with different substrata. The feed for the first reactor was acidified substratum (volatile fatty acid) and the second reactor was fed with non‐acidified substratum (glucose). The purpose of this work was to study the effect of both substrata in regular operation and to analyse the flotation problem which arises when the reactor is fed with a non‐acidified substratum. Finally, the characteristics of the adapted sludge were studied and they were compared with the initial inolucum (sludge). The following observations were noted in relation to the evolution of the sludge during operation: density, TSS content and C, H and N contents remained similar, but the particle size and VSS/TSS increased. The settling volume index decreased and methanogenic and acidogenic activities increased during operation in both reactors. The reactor fed with volatile fatty acids was able to recover from unstable periods faster than the reactor fed with a non‐acidified substratum. The use of an acidified substratum avoided flotation, stabilised the system and reduced the solid content in the effluent. Moreover, it worked properly with partially acidified influents meaning a reduction in the chemical reactive expense required to control acid pH‐value throughout operation. © 1999 Society of Chemical Industry 相似文献
998.
Nazaret Pea-Gil Cristina Santiso-Belln Roberto Gozalbo-Rovira Javier Buesa Vicente Monedero Jesús Rodríguez-Díaz 《International journal of molecular sciences》2021,22(24)
Rotavirus (RV) and norovirus (NoV) are the leading causes of acute gastroenteritis (AGE) worldwide. Several studies have demonstrated that histo-blood group antigens (HBGAs) have a role in NoV and RV infections since their presence on the gut epithelial surfaces is essential for the susceptibility to many NoV and RV genotypes. Polymorphisms in genes that code for enzymes required for HBGAs synthesis lead to secretor or non-secretor and Lewis positive or Lewis negative individuals. While secretor individuals appear to be more susceptible to RV infections, regarding NoVs infections, there are too many discrepancies that prevent the ability to draw conclusions. A second factor that influences enteric viral infections is the gut microbiota of the host. In vitro and animal studies have determined that the gut microbiota limits, but in some cases enhances enteric viral infection. The ways that microbiota can enhance NoV or RV infection include virion stabilization and promotion of virus attachment to host cells, whereas experiments with microbiota-depleted and germ-free animals point to immunoregulation as the mechanism by which the microbiota restrict infection. Human trials with live, attenuated RV vaccines and analysis of the microbiota in responder and non-responder individuals also allowed the identification of bacterial taxa linked to vaccine efficacy. As more information is gained on the complex relationships that are established between the host (glycobiology and immune system), the gut microbiota and intestinal viruses, new avenues will open for the development of novel anti-NoV and anti-RV therapies. 相似文献
999.
Ana Niurka Hernndez‐Lauzardo Guadalupe Mndez‐Montealvo Miguel Gerardo Velzquez del Valle Javier Solorza‐Feria Luis Arturo Bello‐Prez 《Starch - St?rke》2004,56(8):357-363
The chemical, physicochemical and rheological characteristics of Oxalis tuberosa starch were investigated. Oxalis starch presented an apparent amylose content of 33%, similar to maize starch used as control, with a granule size between 25–50 μm with oval and elliptical shapes and A‐type X‐ray diffraction pattern. The gelatinization temperature of oxalis starch was 64.0°C, that was lower than the one determined in maize starch (73.0°C), with an enthalpy value of 12.2 J/g, which was similar to that of maize starch. Both oxalis and maize starch pastes behaved as weak viscoelastic systems with the elastic character (G′) predominating over the viscous character (G′′). An increase in the level of solids in the pastes increased the values of the moduli. The results suggest that heating the systems (gelatinization), causes a more pronounced enhancement in the structure of the maize starch pastes than in that of oxalis starch pastes. Overall, it was concluded that due to its physicochemical, functional and rheological properties, Oxalis starch could be suitable for testing its use in the cosmetic and in the food industry. 相似文献