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11.
12.
Nicolas Vogel Mathieu Jung Noelia L. Bocchio Markus Retsch Maximilian Kreiter Ingo Köper 《Small (Weinheim an der Bergstrasse, Germany)》2010,6(1):104-109
Nanoparticle arrays created by nanosphere lithography are widely used in sensing applications since their localized surface plasmon resonances are extremely sensitive to changes in the local dielectric environment. A major drawback for any biologically oriented sensing application of conventionally produced particle arrays is the lack of stability of the nanoparticles in aqueous media and buffer solutions. Here, a robust and reusable nanoscale sensing platform based on localized surface plasmon resonances of gold nanoparticles embedded in a silicon dioxide matrix is presented. The architecture exhibits extremely high stability in aqueous environments and can be regenerated several times by simple mechanical cleaning of the surface. The platforms surface is ultraflat by design, thus making it an ideal substrate for any bio‐oriented sensing application. 相似文献
13.
Esteban Alfaro Cortés Matías Gámez Martínez Noelia García Rubio 《Applied Intelligence》2007,27(1):29-37
Predicting corporate failure is an important management science problem. This is a typical classification question where the
objective is to determine which indicators are involved in the failure/success of a corporation. Despite the importance of
this problem, until now only classical machine learning tools have been considered to tackle this classification task. The
objective of this paper is twofold. On the one hand, we introduce novel discerning measures to rank independent variables
in a generic classification task. On the other hand, we apply boosting techniques to improve the accuracy of a classification
tree. We apply this methodology to a set of European firms, considering the usual predicting variables such as financial ratios,
as well as including novel variables rarely used before in corporate failure prediction, such as firm size, activity and legal
structure. We show that our approach decreases the generalization error about thirty percent with respect to the error produced
with a classification tree. In addition, the most important ratios deal with profitability and indebtedness, as is usual in
failure prediction studies.
E. A. Cortés · M. G. Martínez · N. G. Rubio. The authors teach Statistics at the Faculty of Economic and Business Sciences in the University of Castilla-La Mancha. Esteban
Alfaro completed his degree in Business in 1999 and got his Ph.D. in Economics in 2005, both in the University of Castilla-La
Mancha. His thesis dealt with the application of ensemble classifiers to corporate failure prediction. Matías Gámez got his
degree in Mathematics at the University of Granada in 1991 and finished a Master in Applied Statistics a year after. He completed
his Ph.D. in Economics at the University of Castilla-La Mancha in 1998 on the application of geo-statistical techniques to
the estimation of housing prices. Noelia García got her degree in Economics at the University of Madrid (UAM) in 1996 and
completed her Ph.D. in Economics in 2004 on the construction of an intelligent and automated system for property valuation
through the combination of neural nets and a geographic information system (GIS). Current research deals with spatial statistics
and the combination of classifiers (decision trees and neural nets) for solving heated topics in the Economics. 相似文献
14.
Noelia Guillén-Hurtado Agustín Bueno-López Avelina García-García 《Journal of Materials Science》2012,47(7):3204-3213
Ce
x
Zr1−x
O2-mixed oxides with three different Ce/Zr ratios (Ce0.8Zr0.2O2, Ce0.5Zr0.5O2 and Ce0.2Zr0.8O2) along with pure cerium and zirconium oxides were prepared by coprecipitation of the metal hydroxides in alkali media and
subsequent calcinations at 500 °C, using two different cerium precursors (Ce(NO3)3·6H2O or (NH4)2Ce(NO3)6). These samples were characterised by N2 adsorption at −196 °C, XRD, Raman spectroscopy, XPS and H2-temperature programmed reduction. Besides, the two mixed oxides with higher cerium content were calcined at higher temperature
(1000 °C) with the additional purpose of studying their thermal stability and phase homogeneity. XRD and Raman spectroscopy
confirm a significant improvement in the insertion of zirconium cations into the ceria lattice when the samples Ce0.8Zr0.2O2 and Ce0.5Zr0.5O2 are synthesised with (NH4)2Ce(NO3)6 instead of Ce(NO3)3·6H2O. This is attributed to a more homogeneous coprecipitation of cerium and zirconium hydroxides, leading to mixed oxides with
better bulk oxygen mobility and smaller lattice parameter. Moreover, the mixed oxides prepared with the (NH4)2Ce(NO3)6 precursor and calcined at 1000 °C exhibit a single phase whereas phase segregation occurs in the counterpart mixed oxides
prepared with the Ce(NO3)3·6H2O precursor. XPS analysis reveal correlations among O/(Ce + Zr) surface atomic ratio and total cerium content for both cerium
precursors. Among the samples calcined at 1000 °C, Ce0.8Zr0.2O2 synthesised with Ce(NO3)3·6H2O is the only one that preserves the low-temperature surface reduction peak, and also shows a BET surface area slightly higher
than those of the rest of samples calcined at high temperature. 相似文献
15.
M. Juárez M.E.R. Dugan N. Aldai J.L. Aalhus J.F. Patience R.T. Zijlstra A.D. Beaulieu 《Food chemistry》2011
To clarify the impact of feeding co-extruded flaxseed on carcass quality and pork palatability, 96 pigs (48 barrows and 48 gilts) were fed three different levels of flaxseed (0%, 5% and 10% of dietary intake) for 76 days. Carcass quality and meat quality characteristics of pure loin muscle and ground pork (20% fat) were evaluated. Fat hardness and belly firmness decreased (P < 0.001) with increasing co-extruded flaxseed. Pigs fed co-extruded flaxseed levels had higher lean yield (P = 0.045) and total lean content (P = 0.034). Loin from barrows had higher fat content compared to gilts (P < 0.001). Co-extruded flaxseed supplementation increased (P < 0.001) omega-3 content in loin and ground pork. Pork flavour intensity and off-flavour intensity scores lowered (P < 0.001) with increasing levels of co-extruded flaxseed, being more accentuated (P = 0.023) in reheated pork chops from barrows. Diet affected all texture and flavour sensory characteristics (P < 0.05) as tissue levels of omega-3 fatty acids increased, likely as a result of increased lipid oxidation. 相似文献
16.
Microwave heating modelling of a green smoothie: Effects on glucoraphanin,sulforaphane and S‐methyl cysteine sulfoxide changes during storage 下载免费PDF全文
17.
Sardiñas N Vázquez C Gil-Serna J González-Jaén MT Patiño B 《International journal of food microbiology》2011,145(1):121-125
Aflatoxins are important mycotoxins that represent a serious risk for human and animal health. These mycotoxins are mainly produced by Aspergillus flavus and Aspergillus parasiticus, two closely related species with different array of aflatoxins. In this work, two specific quantitative PCR (qPCR) assays were developed to detect and quantify both species in wheat flour using primers based on the multicopy ITS2 rDNA target sequence. The species specificity of the assays was tested in a wide range of strains of these species and others colonizing the same commodities. The sensitivity of the assay was estimated in 2.5 pg/reaction in both species. Discrimination capacity for detection and relative quantification of A. flavus and A. parasiticus DNA were analyzed using samples with DNA mixtures containing also other fungal species at different ratios. Both qPCR assays could detect spore concentrations equal or higher than 106 spores/g in flour samples without prior incubation. These assays are valuable tools to improve diagnosis at an early stage and in all critical control points of food chain integrated in HACCP strategies. 相似文献
18.
Noelia Rodríguez Ana Torrado Sandra Cortés José Manuel Domínguez 《Journal of the science of food and agriculture》2010,90(10):1726-1734
BACKGROUND: Lactococcus lactis is an interesting microorganism with several industrial applications, particularly in the food industry. As well as being a probiotic species, L. lactis produces several metabolites with interesting properties, such as lactic acid (LA) and biosurfactants. Nevertheless, L. lactis is an especially demanding species since it has strong nutritional requirements, implying the use of complex and expensive culture media. RESULTS: The results showed the potential of L. lactis CECT‐4434 as a LA and biosurfactant producer. The economical cost of L. lactis cultures can be reduced by replacing the MRS medium by the use of two waste materials: trimming vine shoots as C source, and 20 g L?1 distilled wine lees (vinasses) as N, P and micronutrient sources. From the hemicellulosic fraction, 14.3 g L?1 LA and 1.7 mg L?1 surfactin equivalent were achieved after 74 h (surface tension reduction of 14.4 mN m?1); meanwhile, a simultaneous saccharification and fermentation process allowed the generation of 10.8 g L?1 LA and 1.5 mg L?1 surfactin equivalent after 72 h, reducing the surface tension by 12.1 units at the end of fermentation. CONCLUSIONS: Trimming vine shoots and vinasses can be used as alternative economical media for LA and cell‐bound biosurfactant production. Copyright © 2010 Society of Chemical Industry 相似文献
19.
Antonio González‐Sarrías Juan A. Giménez‐Bastida María T. García‐Conesa María B. Gómez‐Sánchez Noelia V. García‐Talavera Angel Gil‐Izquierdo Carmen Sánchez‐Álvarez Luis O. Fontana‐Compiano Juan P. Morga‐Egea Francisco A. Pastor‐Quirante Francisco Martínez‐Díaz Francisco A. Tomás‐Barberán Juan Carlos Espín 《Molecular nutrition & food research》2010,54(3):311-322
Epidemiology supports the important role of nutrition in prostate cancer (PCa) prevention. Pomegranate juice (PJ) exerts protective effects against PCa, mainly attributed to PJ ellagitannins (ETs). Our aim was to assess whether ETs or their metabolites ellagic acid and urolithins reach the human prostate upon consumption of ET‐rich foods and to evaluate the effect on the expression of three proliferation biomarkers. Sixty‐three patients with BPH or PCa were divided into controls and consumers of walnuts (35 g walnuts/day) or pomegranate (200 mL PJ/day) for 3 days before surgery. Independently of the ETs source, the main metabolite detected was urolithin A glucuronide, (3,8‐dihydroxy‐6H‐dibenzo[b,d]pyran‐6‐one glucuronide) (up to 2 ng/g) together with the traces of urolithin B glucuronide, (3‐hydroxy‐6H‐dibenzo[b,d]pyran‐6‐one glucuronide) and dimethyl ellagic acid. The small number of prostates containing metabolites was likely caused by clearance of the compounds during the fasting. This was corroborated in a parallel rat study and thus the presence of higher quantities of metabolites at earlier time points cannot be discarded. No apparent changes in the expression of CDKN1A, MKi‐67 or c‐Myc were found after consumption of the walnuts or PJ. Our results suggest that urolithin glucuronides and dimethyl ellagic acid may be the molecules responsible for the beneficial effects of PJ against PCa. 相似文献
20.
Seventy-five yearling bulls of the “Asturiana de los Valles” northern-Spanish beef breed (double-muscled, mh/mh, n = 24; heterozygous, mh/+, n = 26; normal, +/+, n = 25) were produced under intensive conditions and the effects of double-muscling genotype on trans-18:1 and CLA isomer profiles were examined. Total trans-18:1 contents, measured as percentages of total fatty acid methyl esters, were 10.98–15.07% in backfat and 8.64–9.46% in muscle, and the major isomer was 10t-18:1 in all animals. In mh/+ animals, 11t-18:1 was the second most abundant trans isomer in muscle whereas in mh/mh and +/+ animals 11t-18:1 and 13t/14t-18:1 were relatively similar. Total CLA percentages were 0.71–0.85% in backfat and 0.32–0.40% in muscle. The highest total CLA percentage found was in mh/+, intermediate in +/+ and lowest in mh/mh animals (P < 0.05). Heterozygous animals had significantly higher percentages of 9c,11t- (P < 0.01), 11t,13c- (P < 0.01) and 9c,11c-18:2 (P < 0.05) and also significantly higher percentages of the sum of 9c,11t-/11t,13c-/11t,13t-18:2. Overall, mh/+ animals produced meat with a slightly better trans and CLA profile (i.e., less 10t-18:1 and more 11t-18:1 and 9c,11t-18:2) than other genotypes, however, further improvements would still be necessary to achieve a profile with a positive health image. 相似文献