Oxidative stress indicators in human and bottlenose dolphin leukocytes in response to a pro-inflammatory challenge

Marine mammals undergo cycles of tissue ischemia and reperfusion during the dive response. Reperfusion injury can result in oxidative tissue damage and the activation of a pro-inflammatory immune response. The risk of oxidative damage is reduced by antioxidants. Our hypothesis is that the reported higher antioxidant defenses within marine mammal tissues provide additional protection in situations that produce oxidative stress, like inflammation, in comparison to terrestrial mammal tissues. Leukocytes were isolated from the whole blood of Pacific bottlenose dolphins (Tursiops truncatus gilli) and humans (Homo sapiens) and were exposed to lipopolysaccharides (LPS, 10 µg/mL) in vitro to simulate a pro-inflammatory challenge. Oxidative stress indicators, including superoxide radical (O₂^•−) production, activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), and glutathione S-transferase (GST), as well as oxidative protein damage, were quantified by spectrophotometry. Following 48 h under experimental conditions, bottlenose dolphin leukocytes produced 1.9 times more O₂^•− but displayed 2.0 times lower protein carbonyl concentrations compared to human leukocytes. Following 48 h under experimental conditions, bottlenose dolphin leukocytes displayed 7.9, 2.0, 11.1, and 3.3 times more activities of CAT, GPx, GR, and GST, respectively, compared to human leukocytes. These results suggest that, under cell culture conditions, the antioxidant defenses in bottlenose dolphin leukocytes provide additional protection against pro-inflammatory challenges in comparison to human leukocytes, likely as an adaptive advantage.     

INFLUENCE OF TEMPERATURE ON SHELF LIFE OF BUTTERHEAD LETTUCE LEAVES UNDER PASSIVE MODIFIED ATMOSPHERE PACKAGING

The aim of the present work was to study the influence of temperature on sensory and microbiological qualities, and on shelf life of butterhead lettuce leaves in passive modified atmosphere packages. Butterhead lettuce was washed and placed under ambient air in 30  ×  40 cm polypropylene bags, and stored at 5, 10 and 15C. A first-order equation was obtained for the development of the evaluated appearance sensory attributes as a function of storage time. For all the evaluated storage temperatures, microbiological shelf lives (14, 17 and 42 days at 5, 10 and 15C) were higher than estimated sensory shelf lives (8, 14 and 26 days at 5, 10 and 15C), showing that shelf life of lettuce in passive modified atmosphere packages was limited by sensory properties and not by microbial growth.

PRACTICAL APPLICATIONS

Sensory shelf life of lettuce in passive modified atmosphere packages was estimated using consumer data, which are an improvement of a more arbitrary criteria presented in most studies. Moreover, if failure criteria used in other studies were applied, consumer rejection at the end of shelf life would be higher, suggesting that more conservative criteria are necessary to assure the product's quality at the end of its shelf life.     

火灾探测过程模拟研究

将火灾模型和烟气传感器结合起来模拟传感器对不同火灾情况的反应。将NIST的FDS模型和Duisburg-Essen大学通讯系统学院开发的烟气传感器模型结合了起来。某火灾烟气流动的模拟结果作为适合烟气传感器模型的输入数据。为了模拟烟气传感器，选择了几个必要的参数来描述烟气、传感器和房间的情况。烟气粒径的大小分布是描述烟气的一个重要参数。对影响粒径大小分布的烟气颗粒的凝结做了适当处理。联合模型的模拟结果与开敞式火灾和阴燃火灾的测量值做了比较。模拟了一个散射光感器和一个电离室。测量和模拟结果显示，传感器模拟的重质取决于所燃烧的燃料。     

Quantifying the structural integrity of nanorod arrays

Arrays of aligned nanorods oriented perpendicular to a support, which are accessible by top‐down lithography or by means of shape‐defining hard templates, have received increasing interest as sensor components, components for nanophotonics and nanoelectronics, substrates for tissue engineering, surfaces having specific adhesive or antiadhesive properties and as surfaces with customized wettability. Agglomeration of the nanorods deteriorates the performance of components based on nanorod arrays. A comprehensive body of literature deals with mechanical failure mechanisms of nanorods and design criteria for mechanically stable nanorod arrays. However, the structural integrity of nanorod arrays is commonly evaluated only visually and qualitatively. We use real‐space analysis of microscopic images to quantify the fraction of condensed nanorods in nanorod arrays. We suggest the number of array elements apparent in the micrographs divided by the number of array elements a defect‐free array would contain in the same area, referred to as integrity fraction, as a measure of structural array integrity. Reproducible procedures to determine the imaged number of array elements are introduced. Thus, quantitative comparisons of different nanorod arrays, or of one nanorod array at different stages of its use, are possible. Structural integrities of identical nanorod arrays differing only in the length of the nanorods are exemplarily analysed.     

Biogenic Amines in Meat and Meat Products

It has been recognized for some time that biogenic amines occur in a wide range of foods, among them meat and meat products. Meat is an important component of the diet in developed countries. The presence of these amines in food is of interest for two reasons: firstly, for toxicological reasons, in the sense that high levels of dietary biogenic amines can be toxic for certain consumers, and secondly, for their role as possible quality indicators. Based on these two premises, the present article offers a new analysis on aspects of toxicology and on the use of biogenic amines as a quality control method, as well as on their presence in meat and meat products. The article focuses particularly on factors affecting the production of biogenic amines, with reference to various parameters relating to microorganisms, meat raw materials, and processing conditions. A better understanding of the factors determining their formation (i.e., microorganisms, raw materials used, and technological processes applied) and their effects could lead to ways of controlling their production, limiting their presence in the end product, and hence, rendering them less toxic.     

SOFTENING KINETICS OF COOKED DRY BEANS AT TEMPERATURES BELOW 100C

New value‐added dry bean products, such as sugar‐coated beans, require a shorter cooking time (15–30 min) and lower temperature (under 100C) than typical canned beans. Michigan bean classes navy, great white northern, small white, small red, dark red kidney, light red kidney, vine cranberry, bush cranberry, pinto and black beans were cooked at constant water temperatures of 90, 95 and 99C for 5–120 min. Isothermal rate constants for texture were estimated at each temperature for each bean class based on a modified first‐order model and an n ^th ‐order model. Heat transfer coefficients were estimated using aluminum beans and lumped capacity analysis. Isothermal parameters (rate constant and activation energy) and a nonisothermal parameter (activation energy) were used to predict texture from dynamic‐temperature experiments. The first‐order model (isothermal) was accurate up to 30 min, but was not appropriate for time greater than 30 min. The n ^th ‐order was considered superior to the modified first‐order model, because only three rather than four parameters needed to be estimated for similar accuracy. The nonisothermal method can save experimental time compared with the isothermal method, because additional experiments at different constant temperatures are unnecessary. A nomograph of equivalent heating time versus constant heating temperature was shown as a useful tool for process design.     

Contribution to the quantification of the conditioning effects of hair dyes

Apart from the problem of colour, the cosmetic properties of hair after dyeing play a vital role both for the cosmetic chemist and the user.
A methodology for a quantitative assessment of these conditioning effects is proposed.
This methodology is based on a realistic approach to the protocols, and uses original apparatus and accessories which take the particular context of the dyeing process into account.
Particular importance is given to studying the length of set hold and the ease of combing. Big differences were observed between three dyes on sale on the market, including their finishing treatment products such as shampoo or rinse.
Contribution à la quantification des effets conditionnants des teintures     

Magnetostrictive Ferrites with Small Change in Coupling Coefficient from 0° to 20°C

Ferrite materials which possess electromechanical coupling coefficients of 30% or more over the temperature interval 0° to 20°C were developed by the control of the various anisotropies. A high order of temperature stability of the coupling coefficient was achieved by a new technique in which a number of ferrites are combined in a composite core structure. Composite transducers made by the technique emerge as single bodies adn not as a composite made up of discrete parts.