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101.
Vural Gökmen Özge Ç. Açar Arda Serpen Francisco J. Morales 《European Food Research and Technology》2008,226(5):1031-1037
The effects of recipe compositions in terms of leavening agent (ammonium and sodium bicarbonates) and sugars (sucrose and
glucose), and baking conditions (temperature and time) on HMF formation in cookies were studied. Five recipes were prepared
by varying the types of leavening agent and sugar. The cookies were baked at different temperatures (180, 200, 210 and 220
°C) for different time (10, 15, 20 and 25 min) to monitor physical and chemical changes in cookie composition in terms of
water activity, pH, surface browning, sugar decomposition, and hydroxymethylfurfural (HMF) formation. Decreasing moisture
to a level under a water activity of 0.4 appeared as the critical point in baking where the rate of HMF formation drastically
increased after this point. After this stage, sucrose decomposed very rapidly if ammonium bicarbonate was used as the leavening
agent at temperatures greater than 200 °C. Replacing ammonium bicarbonate with sodium bicarbonate maintained pH of cookies
ranging between 9.0 and 10.0 during baking, which limited the decomposition of sucrose. 相似文献
102.
We consider a measure of the diversity of a population based on the λ-measure of hypoentropy introduced by Ferreri (1980).
Our purpose is to study its asymptotic distribution for testing hypotheses. A numerical example based on real data is given.
This work was partially supported by the Dirección General de Investigación Cientifica y Técnica (DGICYT) under the contract
PS89-0019. 相似文献
103.
Ana Isabel Haza Adriana Zabala Nuria Arranz Almudena García & Paloma Morales 《International Journal of Food Science & Technology》2005,40(4):437-449
Ten strains of lactic acid bacteria were isolated from a dry fermented sausage and tested for stimulation or inhibition of the viability of Vero and myeloma cells. They did not significantly affect the viability of Vero cells but two isolates (CBL/H and CBL/K) showed a strong and moderate inhibition of the myeloma cell viability (at 108 CFU mL?1, 17.6 and 33.2%, respectively, survival of myeloma cells). The isolates were identified as Lactobacillus sakei by DNA sequencing of the 16S rRNA products of a polymerase chain reaction. No protective effect was found, at the concentrations used, against cytotoxicity of N‐nitrosamines. To test the effect of L. sakei CBL/H and CBL/K on cytokine production [tumour necrosis factor alpha (TNF‐α), interleukin‐1β (IL‐1β) and interleukin‐8 (IL‐8)], the human macrophage cell line (THP‐1) was cultured in the presence and absence of lipopolysaccharide (LPS). Lactobacillus sakei CBL/H and CBL/K induced IL‐1β and IL‐8 release when cells were stimulated with and without LPS. However there was TNF‐α release only in the presence of the LPS. 相似文献
104.
105.
M Santana A?e B Villaverde A?e A Morales Landrove J Pérez Avila 《Canadian Metallurgical Quarterly》1997,49(2):142-144
Tear lactoferrin concentration was measured by ELISA technique and followed in 30 patients undergoing cataract surgery. On the first day following surgery, there was a significant decrease in tear lactoferrin concentration followed by a gradual return to the initial values during the postoperative observation period of 7 days. There was an inverse linear relationship between tear lactoferrin concentration and the tear secretion rate measured by a modified Schirmer I test (1 min) suggesting a constant lactoferrin secretion by the tear glands. Since lactoferrin has known antibacterial and anti-inflammatory effects, the results may contribute to further understanding of the microbial vulnerability or resistance of the eye following surgical procedures. 相似文献
106.
Carlos R. Fadragas E. V. Morales J. A. Muñoz I. S. Bott C. A. Lariot Sánchez 《Journal of Thermal Spray Technology》2011,20(6):1183-1191
A Cu-Al alloy has been used as bond coat between a carbon steel substrate and a final coating deposit obtained by applying
the twin wire electric arc spraying coating technique. The presence of a copper-based material in the composite system can
change the overall temperature profile during deposition because copper exhibits a thermal conductivity several times higher
than that of the normally recommended bond coat materials (such as nickel-aluminum alloys or nickel-chromium alloys). The
microstructures of 420 and 304 stainless steels deposited by the electric arc spray process have been investigated, focusing
attention on the deposit homogeneity, porosity, lamellar structure, and microhardness. The nature of the local temperature
gradient during deposition can strongly influence the formation of the final coating deposit. This study presents a preliminary
study, undertaken to investigate the changes in the temperature profile which occur when a Cu-Al alloy is used as bond coat,
and the possible consequences of these changes on the microstructure and adhesion of the final coating deposit. The influence
of the thickness of the bond layer on the top coating temperature has also been also evaluated. 相似文献
107.
Hydrogen has been widely considered as a potentially viable alternative to fossil fuels for use in transportation. In addition to price competitiveness with fossil fuels, a key to its adoption will be public perceptions of hydrogen technologies and hydrogen fuel. This paper examines public perceptions of riders of a hydrogen hybrid internal combustion engine bus and hydrogen as a fuel source. 相似文献
108.
Single layers of dielectric spheres are an interesting system to study from the fundamental and applied points of view. In this paper we present a systematic study of the influence of structural disorder on the transmission spectra of arrangements of spheres of different compactness. Glass sphere (ε=7) planes were built and their transmission spectra in the microwave range measured. Transmission behavior of this system is highly tolerant to disorder. Even in completely disordered arrangements, there is a highly rejected band with the dips of the spectrum observable. These results suggest that the collective modes of the sphere planes are formed by weakly coupled Mie modes of the individual spheres, and this coupling is governed by the average distance among the spheres. Disorder tolerance allows simpler fabrication procedures where the position of the spheres does not need to be precisely controlled. 相似文献
109.
Yi Zhao Eliud Morales Dvila Xue Li Beiyu Tang Ariana I. Rabinowitsch Jose Manuel Perez-Aguilar Carl P. Blobel 《International journal of molecular sciences》2022,23(21)
The metalloprotease ADAM17 is a key regulator of the TNFα, IL-6R and EGFR signaling pathways. The maturation and function of ADAM17 is controlled by the seven-membrane-spanning proteins iRhoms1 and 2. The functional properties of the ADAM17/iRhom1 and ADAM17/iRhom2 complexes differ, in that stimulated shedding of most ADAM17 substrates tested to date can be supported by iRhom2, whereas iRhom1 can only support stimulated shedding of very few ADAM17 substrates, such as TGFα. The first transmembrane domain (TMD1) of iRhom2 and the sole TMD of ADAM17 are important for the stimulated shedding of ADAM17 substrates by iRhom2. However, little is currently known about how the iRhoms interact with different substrates to control their stimulated shedding by ADAM17. To provide new insights into this topic, we tested how various chimeras between iRhom1 and iRhom2 affect the stimulated processing of the EGFR-ligands TGFα (iRhom1- or 2-dependent) and EREG (iRhom2-selective) by ADAM17. This uncovered an important role for the TMD7 of the iRhoms in determining their substrate selectivity. Computational methods utilized to characterize the iRhom1/2/substrate interactions suggest that the substrate selectivity is determined, at least in part, by a distinct accessibility of the substrate cleavage site to stimulated ADAM17. These studies not only provide new insights into why the substrate selectivity of stimulated iRhom2/ADAM17 differs from that of iRhom1/ADAM17, but also suggest new approaches for targeting the release of specific ADAM17 substrates. 相似文献
110.
J. Miranda M. L. Gallardo D. M. Grimaldi J. A. Rom n-Berrelleza J. L. Ruvalcaba-Sil M. A. Ontalba Salamanca J. G. Morales 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1999,150(1-4):611-615
During Major Temple archaeological site excavations in Downtown Mexico City, the precinct of one of the most important Mexica military caste, the Eagle Warriors, was discovered. The ceremonial enclosure is composed of three rooms surrounded by paintings on 11 stone benches placed against the walls. Nowadays, these paintings and the stones present the effects of different deterioration processes produced by the underground water level, high humidity, and the presence of soil, water, and air pollutants. Ion beam analysis of samples from the benches and wall paintings was performed using PIXE and RBS techniques. Using enrichment factors of elements relative to iron concentrations, possible contamination by sulfur and chlorine salts was found, as well as airborne zinc scavenged by rain. 相似文献