Kardar-Parisi-Zhang asymptotics for the two-dimensional noisy Kuramoto-Sivashinsky equation

We study numerically the Kuramoto-Sivashinsky (KS) equation forced by external white noise in two space dimensions, that is a generic model for e.g. surface kinetic roughening in the presence of morphological instabilities. Large scale simulations using a pseudospectral numerical scheme allow us to retrieve Kardar-Parisi-Zhang (KPZ) scaling as the asymptotic state of the system, as in the 1D case. However, this is only the case for sufficiently large values of the coupling and/or system size, so that previous conclusions on non-KPZ asymptotics are demonstrated as finite size effects. Crossover effects are comparatively stronger for the 2D case than for the 1D system.Comment: 5 pages, 3 figures; supplemental material available at journal web page and/or on reques

Effect of Hyperbaric Storage at Room Temperature on the Activity of Polyphenoloxidase in Model Systems and Fresh Apple Juice

The effect of hyperbaric storage (HS) on polyphenoloxidase activity (PPO) was studied in model solutions and apple juice. Model solutions containing increasing amounts of mushroom (Agaricus bisporus) PPO (up to 26 U) were stored at room temperature at pressure up to 200 MPa. During HS, samples were assessed for residual PPO activity. The enzyme was completely inactivated according to a first-order kinetic model that was used to calculate PPO decimal reduction time (Dp) and pressure sensitivity (zp = 140.8 MPa) in diluted model solutions (2 U PPO). The increase in enzyme concentration (6–26 U) nullified the effect of HS, probably due to protein structure stabilization by self-crowding. The application of HS at 100 and 200 MPa to apple juice promoted a decrease in total bacteria, lactic acid bacteria, yeasts, and molds. These changes occurred in concomitance with the inactivation of PPO (zp = 227.3 MPa). At 200 MPa, PPO inactivation followed a biphasic first-order kinetic, suggesting the presence of PPO isozymes with different pressure sensitivity. The inactivation of PPO was observed to occur more rapidly with increasing storage pressure and led to the maintenance of the original bright juice color. This study proves the capability of HS to control enzyme-related quality decay in fruit juices and, potentially, in many other food matrices suffering enzymatic alteration

Faceted anomalous scaling in the epitaxial growth of semiconductor films

We apply the generic dynamical scaling theory (GDST) to the surfaces of CdTe polycrystalline films grown in glass substrates. The analysed data were obtained with a stylus profiler with an estimated resolution lateral resolution of $l_c=0.3 \mu$m. Both real two-point correlation function and power spectrum analyses were done. We found that the GDST applied to the surface power spectra foresees faceted morphology in contrast with the self-affine surface indicated by the local roughness exponent found via the height-height correlation function. This inconsistency is explained in terms of convolution effects resulting from the finite size of the probe tip used to scan the surfaces. High resolution AFM images corroborates the predictions of GDST.Comment: to appear in Europhysics Letter

HMM-Based tracking of moving terminals in dense multipath indoor environments

This paper deals with the problem of radio localization of moving terminals (MTs) for indoor applications with mixed line-of sight/non-line-of-sight (LOS/NLOS) conditions. To reduce false localizations, a Bayesian approach is proposed to estimate the MT position. The tracking algorithm is based on a Hidden Markov Model (HMM) that permits to jointly track both the MT position and the sight condition. Numerical results show that the proposed HMM method improves the localization accuracy in LOS/NLOS indoor environments

Modulation of Extra Virgin Olive Oil Digestibility through Oleogelation

Background. Extra virgin olive oil (EVOO) represents a key player in the Mediterranean diet for its health-promoting capacity. Although its use as a functional ingredient would be particularly interesting, the direct addition of EVOO to food is challenging due to its liquid state. EVOO conversion into a solid-like material through by oleogelation could enlarge its possible applications. Methods. EVOO was gelled by adding 10% (w/w) of saturated monoglycerides (MG), rice bran waxes (RW), sunflower waxes (SW) or a β-sitosterol/γ-oryzanol mixture (PS). Oleogels were characterised for their structure and subjected to static in vitro digestion. The fatty acid release and destructuring behavior were assessed. Results. The resulting oleogels differed for rheological properties and firmness due to the differences in gel network structure. PS oleogel was the firmest sample followed by SW, RW and MG ones. During in vitro digestion, the fatty acid release was significantly lower for all oleogels compared to unstructured oil. The different network provided by the four oleogelators not only influenced FA release, but also the intestinal micellar size. Conclusion. Acquired results could open new horizons for EVOO application through oleogelation to obtain novel EVOO-based fat replacers and better deliver the EVOO health functionalities

Modeling the effect of the oxidation status of the ingredient oil on stability and shelf life of low-moisture bakery products: The case study of crackers

In packed low-moisture foods such as crackers, oxidation is generally the main cause of quality depletion during storage. It is commonly believed, but scarcely investigated, that product shelf life depends on the oxidative status of the lipid ingredients. In this study, the influence of oxidation degree of the ingredient sunflower oil on cracker oxidative stability and hence shelf life was investigated. To this aim, oil with increasing peroxide values (PVs) (5, 11, and 25 mEqO2/kgoil) was used to prepare crackers. Just after production, crackers presented similar peroxide and rancid odor intensity, probably due to the interactive pathways of oxidative and Maillard reactions. Crackers were packed and analyzed for PV and rancid odor during storage at 20, 40, and 60 \u25e6C. Rancid odor well discriminated cracker oxidative status. Relevant oxidation rates were used to develop a shelf life predictive model based on the peroxide value of the ingredient oil. It was estimated that an oil PV from 5 to 15 mEqO2/kgoil shortens cracker Shelf Life (SL) by 50%, independently of storage temperature. These results demonstrate the critical impact of ingredient quality on product performance on the market

Impact of high-pressure carbon dioxide on polyphenoloxidase activity and stability of fresh apple juice

Freshly-extracted apple juice was exposed to high pressure carbon dioxide (HP-CO2) treatment at 20, 35 and 45 °C at different pressure conditions (6.0, 12.0 and 18.0 MPa) for up to 30 min. Samples were analysed for residual enzymatic activity. The time needed for 90% enzyme inactivation (Dp) decreased when CO2 pressure increased, while the CO2 pressure sensitivity of the enzyme (zp) showed no variation with temperature. The HP-CO2 treatment at 12 MPa and 35 °C allowed the minimum residual enzyme activity (20%) to be reached in 10 min. Samples treated under these conditions showed lower polyphenoloxidase activity and higher microbial stability than untreated apple juice while presenting a sensory fresh-likelihood higher than thermally pasteurized apple juice. © 2016 Elsevier Lt

Effect of different biopolymer-based structured systems on the survival of probiotic strains during storage and in vitro digestion

BACKGROUND: This study aimed to evaluate the protective effect of different biopolymer systems on the viability of two probiotics (Lactobacillus rhamnosus and Streptococcus thermophilus) during storage and in vitro digestion. Methylcellulose (MC), sodium alginate (SA), and whey protein (WP)-based structures were designed and characterized in terms of pH, rheological properties, and visual appearance. RESULTS: The results highlighted that the WP-system ensured probiotic protection during both storage and in vitro digestion. This result was attributed to a combined effect of the physical barrier offered by the protein gel network and whey proteins as a nutrient for microbes. On the other hand, surprisingly, the viscous methylcellulose-based system was able to guarantee good microbial viability during storage. However, this was not confirmed during in vitro digestion. The opposite results were obtained for sodium alginate beads. CONCLUSION: The results suggest that the capacity of a polymeric structure to protect probiotic bacteria is a combination of structural organization and system formulation. \ua9 2020 Society of Chemical Industry

Refractive elastic scattering of carbon and oxygen nuclei: The mean field analysis and Airy structures

The experimental data on the $^{16}$O$+^{12}$C and $^{18}$O$+^{12}$C elastic scatterings and their optical model analysis are presented. Detailed and complete elastic angular distributions have been measured at the Strasbourg Vivitron accelerator at several energies covering the energy range between 5 and 10 MeV per nucleon. The elastic scattering angular distributions show the usual diffraction pattern and also, at larger angles, refractive effects in the form of nuclear rainbow and associated Airy structures. The optical model analysis unambiguously shows the evolution of the refractive scattering pattern. The observed structure, namely the Airy minima, can be consistently described by a nucleus-nucleus potential with a deep real part and a weakly absorptive imaginary part. The difference in absorption in the two systems is explained by an increased imaginary (mostly surface) part of the potential in the $^{18}$O$+^{12}$C system. The relation between the obtained potentials and those reported for the symmetrical $^{16}$O$+^{16}$O and $^{12}$C$+^{12}$C systems is drawn.Comment: 10 pages, 9 figures, Phys. rev. C in pres