Quantitative dietary exposure assessment of the Catalonian population (Spain) to the mycotoxin deoxynivalenol

The mycotoxin deoxynivalenol (DON) is one of the most common contaminants of cereals worldwide, and its occurrence has been widely reported in raw foods and foodstuffs, around the European region, including Catalonia. In the present work, a stochastic methodology has been applied to accurately assess the exposure of the Catalonian population (Spain) to DON through food consumption. Raw contamination data was provided by a large survey conducted in this region, in addition to the raw consumption data from a nutritional study specifically designed to assess the dietary intake of the main foodstuffs related to DON contamination for all population age groups. Contamination and consumption data were combined by simulation using an essentially parametric (P-P) method. The P-P method draws sampling values from distribution functions fitted to consumption and contamination data sets. Moreover, to quantify the accuracy and reliability of the statistics estimates, we built the related confidence intervals using a pseudo-parametric bootstrap method. Considering the results drawn from the P-P simulation method, the Catalonian population should be expected to be exposed at moderated levels of deoxynivalenol, the infants and individuals with ethnic dietary patterns being the most exposed population groups.     

Use of global sensitivity analysis in quantitative microbial risk assessment: application to the evaluation of a biological time temperature integrator as a quality and safety indicator for cold smoked salmon

The aim of this study was to apply a global sensitivity analysis (SA) method in model simplification and to evaluate (eO)^®, a biological Time Temperature Integrator (TTI) as a quality and safety indicator for cold smoked salmon (CSS). Models were thus developed to predict the evolutions of Listeria monocytogenes and the indigenous food flora in CSS and to predict TTIs endpoint. A global SA was then applied on the three models to identify the less important factors and simplify the models accordingly. Results showed that the subset of the most important factors of the three models was mainly composed of the durations and temperatures of two chill chain links, out of the control of the manufacturers: the domestic refrigerator and the retail/cabinet links. Then, the simplified versions of the three models were run with 10⁴ time temperature profiles representing the variability associated to the microbial behavior, to the TTIs evolution and to the French chill chain characteristics. The results were used to assess the distributions of the microbial contaminations obtained at the TTI endpoint and at the end of the simulated profiles and proved that, in the case of poor storage conditions, the TTI use could reduce the number of unacceptable foods by 50%.     

Aluminium composite coatings containing micrometre and nanometre-sized particles electroplated from a non-aqueous electrolyte

The electrolytic codeposition of micro- and nano-sized particles with aluminum from a nonaqueous electrolyte is investigated. SiC, SiO₂, Al₂O₃, TiB₂ and hexagonal BN particles were codeposited with aluminium from an AlCl₃/dimethylsulfone (DMSO₂) electrolyte. The effect of particle concentration and current density on the codeposition rate of SiO₂ with aluminium was investigated. The codeposition of the various particles with Al from AlCl₃:DMSO₂ solutions is very high. The amount of codeposited particles is Langmuir dependent on the particle concentration in the electrolyte. In contrast, the effect of the current density on the amount of codeposited SiO₂ is small.     

La microfissuration d'autodessiccation et la durabilité des BHP et BTHP

This paper presents principal results of an extensive experimental study related to a main objective: to study how microcracks inducing by self-desiccation of High Performance Concrete can call into question the potentially high durability of these concretes. So, durability of 8 concretes of a 20–110 MPa range has been characterised with air permeability measurements. Development of self-desiccation has been determined. The lower the water to cement ratio, the higher is the self-desiccation. Microcracks due to self-desiccation have been quantified for 8 concretes between 28 days and 1 year. The principle and the accuracy of the quantification's tool have been presented. Cracking specific surface area increases with the development of self-desiccation. Air permeability of concretes stored in self-desiccation conditions has been measured. Preliminary results showing that wrong preparation of samples can lead to great and scattered permeability of HSC, then the development of an experimental procedure had been necessary. Its influence on microstructure of concretes has been analysed. With our procedure, permeability does not increase between 28 days and 3 years. Finally, it can be concluded that self-desiccation microcracks in HPC and VHPC do not question the durability.     

DRYING OF WOOD CHIPS WITH AMBIENT AIR

This paper discusses the slow drying of wood chips stacked in deep beds by a flow of ambient air throughout the major part of the year. This kind of drying operation introduces some simplifications to the equation system. The celerity of the drying front is described by an analytical term, then the shape of the front is obtained by an ordinary differential equation. The meteorological data which has been put into the computer determines the progress of the drying front. The flow rate of the blower is determined from the operation characteristics (time allowed, height of the pile, moisture of the product, regulation function) and from the data of the local climate. An additional rudimentary solar collector can improve the efficiency of the system. A period of ten days will be sufficient to calculate the mean data in order to ascertain the progress of the front.     

Kinetics of the electrochemical deposition and dissolution of sodium tungsten bronzes

The electrochemical deposition of sodium tungsten bronzes from Na₂WO₄/WO₃ melts at 700–800°C has been studied. The kinetics of the deposition and the dissolution reactions have been investigated using galvanostatic step, open-circuit decay of electrode potential, and faradaic impedance measurements. The results show that the kinetics of electrochemical deposition are controlled by at least 3 processes: a heterogeneous reaction (surface diffusion of adion), a charge-transfer reaction, and some diffusion in the electrolyte. The relative role of diffusion in the electrolyte seems more important in the dissoluton process than in the deposition reaction.     

Direct,mass-analyzed ion-beam and arc-discharge deposition of diamondlike films

Utilizing mass-analyzed carbon beams at an energy range of 10 eV to 2 keV, we can fabricate diamondlike films with direct deposition. This process allows a very precise adjustment of deposition. This process allows a very precise adjustment of deposition parameters such as ion energy, ion current density, angle of incidence, and control of impurities at an isotopic level. We obtained a density of 3.3-3.5 g/cm³, which is very close to the corresponding values of natural diamond. The most serious disadvantage of direct deposition is a low growth rate. Using an arc-discharge method provides more feasible deposition rates while simultaneously retaining many beneficial effects of direct deposition. These results were also confirmed by spectroscopic studies that revealed similar characteristics on both films. This paper reviews deposition of diamondlike films produced with direct, mass-analyzed ion-beam and arc-discharge methods and presents some properties of these films. *Invited talk in TMS Spring Meeting, Anaheim, CA, February 1990     

New green coatings made from fatty acid dispersions: improvement in barrier properties of biodegradable thermoplasticized-starch substrate

This work was aimed at developing new coatings on biodegradable substrates for possible use in food packaging. In order to study barrier properties of these coatings made from fatty acid dispersions, oxygen permeability, water vapor permeability and also contact angle measurements were carried out. The coatings made from a fatty acid exhibited good barrier properties towards oxygen gas. Moreover, these coatings presented a higher contact angle value than the one obtained directly for the substrate without coating; this can be likely due to the hydrophobic nature of fatty acid and the recrystallization of fatty acid during the drying process.     

Microstructural instabilities during superplastic forging of a nickel-base superalloy compact

The high temperature flow behavior of a nickel-base superalloy powder compact, prepared by hot isostatic pressing has been examined by means of uniaxial compression testing in terms of the microstructures developed during plastic flow. The tests were done isothermally at 1050 and 1100 °C and at constant true strain rates between 10^-5 s^-1 and 1 s^-1. The fine grained compact exhibits some degree of superplasticity which always increases with compressive flow as the grain structure is refined. The faster the rate of deformation, the finer is the grain size produced at high strains, when steady state conditions of flow appear to develop. By deforming to different strains at a given strain rate or into the steady state regimes at various strain rates, grain sizes in the range 1 to 5 pun were produced. By unloading and restraining the test pieces in situ, the effect of grain size on the onset of plastic flow has been examined and the yield stress observed to increase with grain size. It is shown that, in this material, hardening or softening occurs during flow depending on the size of the initial grains. The changes in microstructure and flow stress observed during deformation are analyzed and the potential offered for control of the microstructure during isothermal forging is discussed.