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In the present work, fresh beef was treated with 3 g/L sodium lactate, while fresh beef without treatment served as negative control. Based on the comprehensive analyses of pH, total volatile basic nitrogen (TVB-N), colour, and microbial quality, the acceptable shelf life of chilled beef treated with sodium lactate was six days, while the control was acceptable for three days. Sodium lactate usage was conducive to hygiene levels improvement. Lactobacillus spp. and Weissella spp. sharply displaced the Ralstoni spp. with high potential spoilage, and became the predominant bacteria. Moreover, the proliferation of Serratia spp. was completely controlled by sodium lactate treatment. Sodium lactate usage exhibited a better pH stability and outstanding colour stability together with antibacterial efficacy. Furthermore, we suggested the mechanistic insights on colour stability and antibacterial efficacy of sodium lactate due to its roles in the regeneration of reduced nicotinamide adenine dinucleotide (NADH) together with pH regulation. [ABSTRACT FROM AUTHOR]

Tsunamis entering into shallow water regions may become highly nonlinear and this may be due to the irregularity of sea bottom roughness relative to the water depth and the complex coastline geometry. The elliptic mild-slope equation is commonly used to predict the nonlinear wave propagation in shallow water regions but it requires huge amount of computer resources which may not be practical for tsunami propagation predictions. An efficient finite element approach has been adopted in the present project to resolve the nonlinear problem of wave transformation in near shore zones as well as to better conform the model grids to any complex coastline configurations. The efficient approach is based on the wave action conservation equation that takes into account of wave refraction-diffraction and energy dissipation due to bottom roughness. An operator splitting scheme is employed to solve the wave action conservation equation. Firstly, to increase numerical stability, the Eulerian-Lagrangian method is applied to solve the advection terms in the equation. The horizontal terms are then discretized by an implicit finite element method and, finally, the vertical terms are approximated by an implicit finite difference method. A nominal-time iteration method is used to efficiently solve the non-linear irrotational wave number equation for the wave direction. Over 6000 nine-node elements have been used to mesh the Pearl River estuary region. The boundary conditions are based on the results obtained from a simulation applied for a larger computation domain encompassing the entire South China Sea. The computed result provides a general picture of tsunami propagation in the desired region. Model validation and result verification, however, are necessary for any future prediction exercises.

In recent years, the frequency and intensity of drought–flood abrupt alterations due to global climate change have drastically increased. In contrast, plant response to the drought-flood abrupt alternations remains unclear. In the current study to reveal maize’s physiological response to drought-flood abrupt alternations, these were carried out in two stages in this study, i.e., three levels of water deficit (WD, i.e., 75%, 65%, and 55% of the field capacity) in stage I, and then five durations of flooding (75%-WDi, 65%-WDi and 55%-WDi) in stage II. The results indicated that the 65%-WDi treatment significantly decreased the leaf area and biomass of maize seedlings in stage I, while maintaining plant growth and reaching the control level in stage II. Abscisic acid (ABA) concentration in maize leaves and roots of 0-5 cm depth was sensitive to drought stress. Under drought–flood abrupt alternations, the root system in 55%- WD5 and 65%-WD7 exhibited strong ABA signal, which was sensitive to drought-flood abrupt alternations. Therefore, at the maize seedling stage, proper control of soil moisture is beneficial for improving stress tolerance at later stages, but stress tolerance after drought–flood abrupt alterations is related to the degree of drought exposure at the early stage. [ABSTRACT FROM AUTHOR]

A generalized infinite element is presented by combining following aspects: (1) The geometry mapping in the Cartesian system is chosen so as to facilitate the generation of infinite element mesh; (2) The decay variable is defined as the in situ major axis of the confocal ellipse where the field point is located, so it is dependent not only on the infinite-directional coordinate but on the finite-directional one(s); (3) The shape function is constructed so that it exactly satisfies the multipole expansion along the edges of the infinite element; (4) The conjugated weighting function is adopted to eliminate the harmonic terms from the integrands; and (5) the more proper form of phase factor and weighting factor is recommended. Compared with the Bettess element and the Astley element, the present element greatly reduces the element number within the finite element zone for problems with a large aspect ratio. Compared with the Burnett element and the modified Burnett element, the present element permits the free orientation of the infinite element, and thereby is suitable for more general exterior problems, either of a closed surface (source) or of an opening surface (source). Several typical examples are given and their results show that the generalized infinite element is robust and flexible. [DOI: 10.1115/1.1855927] Keywords: Mapped Infinite Element, Multi-Pole Expansion, Geometry Mapping, Shape Functions, Conjugated Weighting Functions, Weighting Factor, Phase Factor

Microcystis occurs as colonies in natural waters and always disaggregates into unicellular cells in the laboratory. Cadmium (Cd) could stimulate Microcystis colony formation in the laboratory. To elucidate the mechanism involved in cadmium-induced colony formation of Microcystis, microcystin (MC) changes and proteomic responses in M. aeruginosa treated with seven concentrations of Cd (0, 0.0125, 0.0250, 0.0500, 0.1000, 0.2000 and 0.4000 mg/L) for 40 h were studied. The results showed that seven concentrations of Cd except 0.4000 mg/L Cd could significantly induce colony formation (P < 0.05), and the Cd-induced colony-stimulating effects were accompanied with the increased intracellular MC-RR production. A total of 1170 proteins, including seven MC biosynthesis-related enzymes and seven polysaccharide biosynthesis-related enzymes, were identified using 2D-LC-MS/MS combined with isobaric tags for relative and absolute quantitation (iTRAQ). 0.4000 mg/L Cd could downregulate all the identified enzymes involved in MC and polysaccharide biosynthesis while most of these enzymes were upregulated during Cd-induced colony formation. Cd might stimulate Microcystis colony formation via increasing the biosynthesis of MC and polysaccharide. [ABSTRACT FROM AUTHOR]

An SRAM (static random access memory)-based re-programmable FPGA (field programmable gate array) is investigated for space applications. A new commercial prototype, named the RS family, was used as an example for the investigation. The device is fabricated in a 0.25[micro]m CMOS technology. Its architecture is reviewed to provide a better understanding of the impact of single event upset (SEU) on the device during operation. The SEU effect of different memories available on the device is evaluated. Heavy ion test data and SPICE simulations are used integrally to extract the threshold LET (linear energy transfer). Together with the saturation cross-section measurement from the layout, a rate prediction is done on each memory type. The SEU in the configuration SRAM is identified as the dominant failure mode and is discussed in detail. The single event transient error in combinational logic is also investigated and simulated by SPICE. SEU mitigation by hardening the memories and employing EDAC (error detection and correction) at the device level are presented. For the configuration SRAM (CSRAM) cell, the trade-off between resistor de-coupling and redundancy hardening techniques are investigated with interesting results. Preliminary heavy ion test data show no sign of SEL (single event latch-up). With regard to ionizing radiation effects, the increase in static leakage current (static [I.sub.CC)) measured indicates a device tolerance of approximately 50krad(Si).

The optimal reaction model for analysis of thermal decomposition of various types of biomasses is currently under debate. Four established models for the kinetic analysis ofPolygonum lapathifoliumwere employed in this study: double extrapolation method, Flynn–Wall–Ozawa method (FWO), distributed activation energy model (DAEM), and global kinetic model. The values of activation energy and frequency factor calculated by global kinetic model are much lower than that of the other three methods. Moreover, it has been demonstrated that the activation energy analyzed by FWO method and DAEM is widely distributed and is not directly related to the heating rates, which are more objective than double extrapolation method and global kinetic model. [ABSTRACT FROM PUBLISHER]