Physicochemical Characterization of a Heat Treated Calcium Alginate Dry Film Prepared with Chicken Stock

Solid sodium alginate was dissolved into chicken stock in order to give a final alginate concentration of 0.9 percent (w/v). Calcium ions present in chicken stock were enough to induce ionic gelation. After drying, Fourier transform infrared spectroscopy, thickness and mechanical properties of films obtained were determined. Calcium alginate‐chicken stock films were heated at 130 °C for different times between 0 and 15 min. Mechanical and optical studies, differential scanning calorimetry, visual aspect and scanning electron microscopy were carried out to describe physicochemical properties of heat treated films. Heating developed a maroon ochre color and increased the brittleness (crispness) of the films related to the intensity of the treatment. Differential scanning thermometry and study on appearance of the films suggested that Maillard reactions may be responsible for the observed changes. Maillard reactions mainly occurred between reducing sugar monomers and free amino groups of gelatin peptides present in the chicken stock, and between alginate and gelatin peptides to a lesser extent. In addition, the plasticizing effect of fat added with chicken stock was also studied. These studies suggest a potential use of heat treated chicken stock films as a substitute of roasted chicken skin.     

Semiparametric additive models under symmetric distributions

In this paper we discuss estimation and diagnostic procedures in semiparametric additive models with symmetric errors in order to permit distributions with heavier and lighter tails than the normal ones, such as Student-t, Pearson VII, power exponential, logistics I and II, and contaminated normal, among others. Such models belong to the general class of statistical models GAMLSS proposed by Rigby and Stasinopoulos (Appl. Stat. 54:507–554, 2005). A back-fitting algorithm to attain the maximum penalized likelihood estimates (MPLEs) by using natural cubic smoothing splines is presented. In particular, the score functions and Fisher information matrices for the parameters of interest are expressed in a similar notation of that used in parametric symmetric models. Sufficient conditions on the existence of the MPLEs are presented as well as some inferential results and discussions on degrees of freedom and smoothing parameter estimation. Diagnostic quantities such as leverage, standardized residual and normal curvatures of local influence under two perturbation schemes are derived. A real data set previously analyzed under normal linear models is reanalyzed under semiparametric additive models with symmetric errors.     

Influence of molecular weight on the electrification of linear polyethylenes during extrusion: Identification of two different mechanisms for charge generation

The phenomenon of electrification is the accumulation of electric charge in a material. Polymers may become electrified when subjected to intense friction during their processing or under working conditions and the accumulated electric charge may change their adhesion and friction properties. In this work, a study of the influence of molecular weight and chain mobility on the electrification of linear low‐density polyethylenes under continuous extrusion is presented. The use of different die materials, polymer processing additives, as well as slip and no slip flow conditions allowed the identification of two different mechanisms for electric charge generation in the melts; namely, the stripping of an electrical double layer acting in the absence of slip, and dynamic frictional electrification, or tribocharging acting under strong slip conditions. The magnitude of the electric charge was found to increase with polymer molecular weight and die length, and exhibited a local maximum as a function of the average velocity of the melt in both cases. The height of the maximum increased along with the molecular mobility. The experimental results were compared with the numerical solution of the equation of continuity for charge transport and it is shown that it does not describe the experimental results because it does not consider the additional mechanism of charge generation introduced by strong slip at the die wall. POLYM. ENG. SCI., 2008. © 2007 Society of Plastics Engineers     

Effect of location in the canopy on the colour development of three apple cultivars during growth

BACKGROUND: Homogeneity in appearance is one of the quality aspects asked for in the supply chain. Decreasing the biological variation in batches of harvested apples (cultivars Braeburn, Fuji and Gala) becomes increasingly important. Skin colour is one of the aspects that determine both optimal harvest and stage of development. Skin colour is affected by location in the canopy. The rules of development of biological variation are now established and will be used on skin colour data. RESULTS: The Minolta colour aspects a*, b* and L* measured before commercial harvest change in a sigmoidal fashion and can be analysed including the biological variation, with a logistic model in indexed nonlinear regression, obtaining explained parts of above 90%. The mechanism of colour change is not affected by state of development or location in the canopy. The location in the canopy affects the intensity of both red and green colouring compounds. The variation in colouration is not affected by the location in the canopy. CONCLUSION: The red‐coloured apple cultivar (Gala) depends more on the location in the canopy than the less‐coloured cultivars (Fuji and Braeburn). The colour development in Fuji apples is considerably slower, with a much larger variation in stage of development. The location in the canopy affects all aspects of biological variation (biological shift factor and asymptotic starting level of colouration) for all three colour aspects L*, a* and b*, but only the mean value, not the standard deviation. The biological shift factors per colour aspects are linearly related. Once induced, variation remains constant during development. Copyright © 2012 Society of Chemical Industry     

Involvement of the transepithelial calcium transport disruption and the formation of epididymal stones in roosters

Epididymal lithiasis is a dysfunction of unknown origin characterized by the formation of calcium stones into the lumen of efferent ductules of roosters. Affected animals present an imbalance in the hormonal responsive systems that regulate the expression of proteins involved in the transepithelial calcium transport, as TRPV6, CaBP-D28K, NCX1, and PMCA. Because the efferent ductules are the major site of fluid and calcium reabsorption in excurrent ducts, it was hypothesized that impairment in local calcium homeostasis would lead to lithiasis. To test this hypothesis, we addressed the expression of these proteins in the epididymal region of affected animals. The present study focused on the investigation of the occurrence, tissue distribution, and physiological impact of the transepithelial calcium transport in roosters under normal and pathological conditions. The results showed that affected roosters presented a significant increase in TRPV6 and CaBP-D28k levels, whereas NCX1 and PMCA were not changed. Such alterations were more conspicuous in the proximal efferent ductules, in which was also observed accumulation of calcium within the epithelial cells. These findings provided the first evidences for the involvement of alteration in the expression of proteins essential for calcium reabsorption as a plausible mechanism for the formation of calcium stones within efferent ductules.     

Influence of water activity and temperature on growth and mycotoxin production by Alternaria alternata on irradiated soya beans

The aim of this study was to determine the effects of water activity (a_w) (0.99-0.90), temperature (15, 25 and 30 °C) and their interactions on growth and alternariol (AOH) and alternariol monomethyl ether (AME) production by Alternaria alternata on irradiated soya beans. Maximum growth rates were obtained at 0.980 a_w and 25 °C. Minimum a_w level for growth was dependent on temperature. Both strains were able to grow at the lowest a_w assayed (0.90). Maximum amount of AOH was produced at 0.98 a_w but at different temperatures, 15 and 25 °C, for the strains RC 21 and RC 39 respectively. Maximum AME production was obtained at 0.98 a_w and 30 °C for both strains. The concentration range of both toxins varied considerably depending on a_w and temperature interactions. The two metabolites were produced over the temperature range 15 to 30 °C and a_w range 0.99 to 0.96. The limiting a_w for detectable mycotoxin production is slightly greater than that for growth. Two-dimensional profiles of a_w × temperature were developed from these data to identify areas where conditions indicate a significant risk from AOH and AME accumulation on soya bean. Knowledge of AOH and AME production under marginal or sub-optimal temperature and a_w conditions for growth can be important since improper storage conditions accompanied by elevated temperature and moisture content in the grain can favour further mycotoxin production and lead to reduction in grain quality. This could present a hazard if the grain is used for human consumption or animal feedstuff.     

Automatic detection of pathological voices using complexity measures, noise parameters, and mel-cepstral coefficients

This paper proposes a new approach to improve the amount of information extracted from the speech aiming to increase the accuracy of a system developed for the automatic detection of pathological voices. The paper addresses the discrimination capabilities of 11 features extracted using nonlinear analysis of time series. Two of these features are based on conventional nonlinear statistics (largest Lyapunov exponent and correlation dimension), two are based on recurrence and fractal-scaling analysis, and the remaining are based on different estimations of the entropy. Moreover, this paper uses a strategy based on combining classifiers for fusing the nonlinear analysis with the information provided by classic parameterization approaches found in the literature (noise parameters and mel-frequency cepstral coefficients). The classification was carried out in two steps using, first, a generative and, later, a discriminative approach. Combining both classifiers, the best accuracy obtained is 98.23% ± 0.001.     

Nano-Oncologicals: A Tortoise Trail Reaching New Avenues

Research efforts towards cancer therapeutics have resulted in the development of a variety of pharmacological molecules, including small synthetic molecules and biological drugs (RNA-based therapies and monoclonal antibodies—mAbs), intended to target tumor or immune-related cells, or their signaling mediators. The majority of them present important biopharmaceutical problems related to their difficulties for overcoming biological barriers and reach their targets. Nanotechnology has been, for more than 60 years, trying to solve these problems. As knowledge in drug discovery, molecular biology, and biomaterials advances, there has been significant progress in the adequate design of nanodelivery strategies that may significantly contribute to the exploitation of the new therapies. This review provides a critical overview of the current potential of nanotechnology to solve problems associated with the different categories of drugs. Starting with the general concept of passive and active targeting, it presents the distinct advantages that delivery technologies have shown to date for improving the therapeutic outcome of small drugs with cytotoxic activity, RNA- and mAb-based therapies. Moreover, it precisely describes the benefits of combining immunotherapies and nanotechnology. The most advanced technologies are put into perspective in relation to their translational pathway and the future avenues for nano-oncologicals.     

Evaluating the computational performance of the Xilinx Ultrascale+ EG Heterogeneous MPSoC

The Journal of Supercomputing - The emergent technology of Multi-Processor System-on-Chip (MPSoC), which combines heterogeneous computing with the high performance of Field Programmable Gate Arrays...     

Oligomeric poly(ether‐imide)s bearing ortho trifluoromethyl groups: Solubility,thermal studies,and optical properties

In the development of processable high‐temperature materials, six new aromatic poly(imide)s based on diamines containing ortho trifluoromethyl groups, ether linkages and R,R‐methylenes moieties (R = Me or Ph) and previously reported dianhydrides have been synthesized vía polycondensation reactions. All polymers were obtained with good yields, were soluble in a variety of polar aprotic solvents, and exhibited inherent viscosity (η_inh) values between 0.15 and 0.20 dL g^?1, which is indicative of low molecular‐weight species. Preliminary studies of their physical properties were carried out. The new materials were transparent in the visible region and they exhibited thermal decomposition temperatures ranging from 475 to 545 °C and glass‐transition temperatures varying from 288 to 304 °C. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46613.