Implications of the use of semicarbazide as a metabolic target of nitrofurazone contamination in coated products.

Data from the Brazilian Agricultural Ministry show that before the implementation of the Brazilian programme of nitrofuran control in February 2003, the cases of contamination of Brazilian chicken by nitrofurans were almost exclusively due to furaltadone. After May 2003, such cases decreased until no more reports of Brazilian chicken contamination with this nitrofuran were reported. Curiously, after April 2003, an increase was observed in the numbers of contaminated samples by semicarbazide, the target metabolite of nitrofurazone. Most Brazilian chicken found to be contaminated with semicarbazide has been covered with flour, salt and spices. For this reason, the authors' laboratory initialized a programme for tracing possible sources of food contamination by semicarbazide. After several semicarbazide positives in flour of controlled origin (results varying between 2.2 and 5.2 microg kg(-1)), the different additives used in the cereal industry as flour improvement agents were studied. The results indicate that the compound azodicarbonamide was responsible for the source of the contaminant semicarbazide.     

Postharvest evaluation of soilless-grown table grape during storage in modified atmosphere

BACKGROUND: Soilless growth systems, developed mainly for vegetables and ornamental crops, have also been used recently as an alternative to soil culture for table grape in order to achieve optimal production performance. In this study, sensory, physical and chemical parameters were analysed in table grapes obtained from soil and soilless growth systems at harvest and during storage in air or modified atmosphere. RESULTS: At harvest, soilless‐grown berries were 30% firmer than those grown in soil. Moreover, they showed 60% higher antioxidant activity and total phenol content than soil‐grown fruits. Modified atmosphere storage resulted in a better quality of table grapes compared with those stored in air. Furthermore, soilless growth was more suitable than soil growth for preserving visual quality and controlling rachis browning and weight loss. CONCLUSION: Since the soilless system produces berries that are cleaner and of higher quality than those grown in soil, the implementation of soilless growth for the production of health‐promoting and convenience fruits is suggested. Copyright © 2011 Society of Chemical Industry     

Online comprehensive RPLC × RPLC with mass spectrometry detection for the analysis of proteome samples

LC-MS-based shotgun proteomics relies both on the power of the separation techniques and the sensitivity of detection methods. As a viable alternative to classical approaches in this field, we developed a fully automated, comprehensive 2D LC system, in which RPLC × RPLC was coupled to MS detection, for the first time, and applied for the analysis of tryptic digests obtained from α-casein and dephosphorylated α-casein. The use of a significantly different pH in the two dimensions allowed us to attain high peak capacity, despite the employment of novel identical stationary phases. Furthermore, such a combination addresses compatibility issues, thus allowing straightforward interfacing in online 2D LC configuration, as well as direct linkage to a mass spectrometer. A theoretical peak capacity of ca. 8500 was calculated for the setup, employing four serially coupled C18 columns in the first dimension (600 × 2.1 mm, 2.7 μm d.p.), operated under basic conditions, and 3 cm length of the same stationary phase (30 × 4.6 mm, 2.7 μm d.p. column), under acidic conditions, for fast second dimension analysis.     

An unusual foreign body in the rectum

This is the report of an unusual foreign body in the rectum which was a complication of the migration of an esophageal Celestin's prosthesis.     

Quantifying the relevance and stage of disease with the Tau image technique

Discusses a complementary diagnostic imaging technique based on infrared functional imaging. It is concluded that the Tau images obtained with our method provide a large amount of information. The method, in fact, correctly depicts the ill and symptomatic situation; moreover, it is able to identify the surface projection onto the skin of the damaged areas and, by means of the evaluated value of the Tau time, the stage of the disease. Additionally, it is possible to evaluate the evolution of the clinical situation following a rehabilitation therapy and to quantitatively compare the different Tau images recorded at different times.     

A fuzzy approach to some classification problems

An appropriate algebraic structure was previously defined which can be regarded as a possible alternative to the theory of approximate reasoning, [A. Gisolfi, Fuzzy Sets Syst. 44 , 37–43 (1992)]. In this article we aim at extending the operations of the structure in order to cope with classification problems. the theoretical aspects are emphasized in order to give an adequate background to the possible applications. After defining the basic elements and the related operations, the structure is implemented by means of Prolog. Finally the relationship between the structure and the problems of classification is discussed in some detail. © 1993 John Wiley & Sons, Inc.     

Preparation, characterization and CO sensing of Au/iron oxide thin films

The preparation and characterization of Au-doped iron oxide thin films is reported. Doped-thin films have been prepared by a liquid-phase deposition (LPD) method from aqueous solutions in the presence of a reactive atmosphere containing NH₃. The morphology and microstructure of the prepared films are described. The effect of some process parameters (precursor solution concentration, calcination temperature) on the film formation, thickness and microstructure are investigated. Sensor devices based on Au/Fe₂O₃ thin films deposited on alumina by the LPD method, are sensitive to CO at operating temperatures between 200–400 °C.     

Simplified correlation models for CO/H2 chemical reaction times

This paper provides simplified correlation models for CO/H₂ chemical reaction times. The procedure used for the CO/H₂ simplified modeling utilized the full chemical kinetics mechanism run over a range of temperatures from 700 to 1800 K, pressures from 0.5 to 50 atm, mixtures from 0% to 95% CO, and equivalence ratios from 0.2 to 2.0 to determine ignition (or reaction) time. The correlations for ignition times are given in formulas as functions of equivalence ratio, temperature, and pressure. Two different forms of correlations were obtained, one being a single, overall correlation and the other a two-stage correlation representing regions of high and low temperatures. These correlations are shown to work well over a range of chemical time scales spanning ten orders of magnitude. The correlations are also compared with measured data from the literature.