Kinetics of the thermal degradation of patulin in the presence of ascorbic acid

Degradation of the mycotoxin patulin between 25 and 85 °C without and with added ascorbic acid was studied, and the effectiveness of linear and nonlinear models for predicting reaction rates was compared. In agreement with previous reports, ascorbic acid significantly increased (P ≤ 0.05) the rate of patulin degradation at all temperatures studied. The data for patulin degradation in the absence of ascorbic acid were adequately modeled using a zero-order linear kinetic model. However, the predictive abilities of zero and higher-order linear models were not adequate to describe the more complex reactions that likely occurred when ascorbic acid was added. In contrast, the nonlinearWeibull model adequately described the patulin-ascorbic acid reaction throughout the temperature range studied. Zero-order rate constants and Weibull scale values for each of the respective reactions followed the Arrhenius law. Activation energies of 58.7 ± 3.9 and 29.6 ± 1.9 kJ mol⁻¹ for the reaction without and with ascorbic acid, respectively, confirmed decreased patulin stability in the presence of ascorbic acid and suggested that the mechanisms for the 2 degradation reactions were different

A Predictive Toxicokinetic Model for Nickel Leaching from Vascular Stents

In vitro testing methods offer valuable insights into the corrosion vulnerability of metal implants and enable prompt comparison between devices. However, they fall short in predicting the extent of leaching and the biodistribution of implant byproducts under in vivo conditions. Physiologically based toxicokinetic (PBTK) models are capable of quantitatively establishing such correlations and therefore provide a powerful tool in advancing nonclinical methods to test medical implants and assess patient exposure to implant debris. In this study, we present a multicompartment PBTK model and a simulation engine for toxicological risk assessment of vascular stents. The mathematical model consists of a detailed set of constitutive equations that describe the transfer of nickel ions from the device to peri-implant tissue and circulation and the nickel mass exchange between blood and the various tissues/organs and excreta. Model parameterization was performed using (1) in-house-produced data from immersion testing to compute the device-specific diffusion parameters and (2) full-scale animal in situ implantation studies to extract the mammalian-specific biokinetic functions that characterize the time-dependent biodistribution of the released ions. The PBTK model was put to the test using a simulation engine to estimate the concentration-time profiles, along with confidence intervals through probabilistic Monte Carlo, of nickel ions leaching from the implanted devices and determine if permissible exposure limits are exceeded. The model-derived output demonstrated prognostic conformity with reported experimental data, indicating that it may provide the basis for the broader use of modeling and simulation tools to guide the optimal design of implantable devices in compliance with exposure limits and other regulatory requirements

Effect of olive mill wastewater phenol compounds on reactive carbonyl species and Maillard reaction end-products in ultrahigh-temperature-treated milk

Thermal processing and Maillard reaction (MR) affect the nutritional and sensorial qualities of milk. In this paper an olive mill wastewater phenolic powder (OMW) was tested as a functional ingredient for inhibiting MR development in ultrahigh-temperature (UHT)-treated milk. OMW was added to milk at 0.1 and 0.05% w/v before UHT treatment, and the concentration of MR products was monitored to verify the effect of OMW phenols in controlling the MR. Results revealed that OMW is able to trap the reactive carbonyl species such as hydroxycarbonyls and dicarbonyls, which in turn led to the increase of Maillard-derived off-flavor development. The effect of OMW on the formation of Amadori products and N-e-(carboxymethyl)-lysine (CML) showed that oxidative cleavage, C2–C6 cyclization, and the consequent reactive carbonyl species formation were also inhibited by OMW. Data indicated that OMW is a functional ingredient able to control the MR and to improve the nutritional and sensorial attributes of mil

Pilot-scale biogas and in-situ struvite production from pig slurry: A novel integrated approach

Excess ammonia produced during the decomposition of nitrogen-rich substrates inhibits the anaerobic digestion (AD) process while it increases the concentration of ammonium nitrogen (NH4+) in the digestate. Digestate is commonly applied to farmland, causing nitrogen loss via runoff and volatilization. Therefore, developing an integrated strategy to promote the overall efficiency of AD systems susceptible to ammonia toxicity events, is worthy of consideration. Herein, a step-feeding approach to combat ammonia toxicity in AD process in which, intermittent rather than continuous substrate feeding was tested. A pilot-scale, mesophilic (37 ± 1 °C), fed-batch AD reactor (working volume ∼ 6.67 m3), was operated as the biomethanation step in a novel biorefinery concept, to recover bioenergy and nutrients (struvite) from pig slurry. The results showed that methane production yield achieved was 89.7 % of the theoretical at high ammonia levels (4.44 g NH4+-N L−1), indicating an efficient AD process under strong ammonia stress. The production rate of precipitate was 4.0 kg t−1 feedstock, while X-Ray Diffraction analysis revealed that purity of struvite crystal was 98 % w/w. Orthorhombic crystals and homogeneous distribution of significant elements (O, P, N, and Mg) in the precipitate were observed through scanning electron microscopy coupled with energy dispersive X-ray analysis. Recoveries of nitrogen and phosphorus were 48.5 % and 68.5 % from the digestate, respectively. Furthermore, the chemical and sanitary (i.e., Escherichia coli, Enterobacteriaceae and Salmonella) indicators of the precipitate were in line with the EU Fertilizer Regulation. Overall, the obtained results indicate that it is possible to establish an integrated efficient nutrient and energy recovery process for the simultaneous production of high-yield biogas and high-purity struvite fertilizer from pig slurry, which could yield a gross profit of 5.79 € t−1 feedstock

Atlas der Datenkörper. Körperbilder in Kunst, Design und Wissenschaft im Zeitalter digitaler Medien

Digitale Technologien und soziale Medien verändern die Selbst- und Körperwahrnehmung und verzerren, verstärken oder produzieren dabei spezifische Körperbilder. Die Beiträger*innen kartographieren diese Phänomene, fragen nach ihrer medialen Existenzweise sowie nach den Möglichkeiten ihrer Kritik. Dabei begegnen sie ihrer Neuartigkeit mit einer transdisziplinären Herangehensweise. Aus sowohl der Perspektive künstlerischer und gestalterischer Forschung als auch der Kunst-, Kultur- und Medienwissenschaft sowie der Psychologie und Neurowissenschaft wird die Landschaft rezenter Körperbilder und Techniken einer digitalen Körperlichkeit untersucht

Animal Bodies and Ontological Discourse in the Greek Neolithic

The present article tries to assess the ways that animal bodies were represented in the Neolithic of Northern Greece. Contending that representations always have a material presence ( be they spoken, depicted or anything else), an attempt is made to sort out how the specificity of this presence constitutes a frame of reference for the deployment of social action. Animal representations seem to be particularly related with certain materials, especially clay, and certain objects, mostly clay vessels. It is suggested that these objects allow animals to be incorporated in social action in a very specific manner, one that is further defined by the contexts of their use