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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2009.03.034 Byline: J. Dekeirsschieter (a), F.J. Verheggen (a), M. Gohy (b), F. Hubrecht (c), L. Bourguignon (c), G. Lognay (d), E. Haubruge (a) Keywords: Forensic entomology; Odour analysis; Pig carcasses; Decompositional process; Volatile passive sampling; Radiello.sup.[R] Abstract: Forensic entomology uses pig carcasses to surrogate human decomposition and to investigate the entomofaunal colonization. Insects communicate with their environment through the use of chemical mediators, which in the case of necrophagous insects, may consist in the cadaveric volatile organic compounds (VOCs) released by the corpse under decomposition. Previous studies have focused on cadaveric VOCs released from human corpses. Nevertheless, studies on human corpses are restricted for many reasons, including ethics. Forensic entomologists use pig as animal model but very few information are available about the decompositional VOCs released by a decaying pig carcass. We here tested a passive sampling technique, the Radiello.sup.[R] diffusive sampler, to monitor the cadaveric VOCs released by decomposing pig carcasses in three biotopes (crop field, forest, urban site). A total of 104 chemical compounds, exclusively produced by the decompositional process, were identified by thermal desorption interfaced with gas chromatography and mass spectrometry (TDS-GC-MS). Ninety, 85 and 57 cadaveric VOCs were identified on pig carcasses laying on the agricultural site, the forest biotope and in the urban site, respectively. The main cadaveric VOCs are acids, cyclic hydrocarbons, oxygenated compounds, sulfur and nitrogen compounds. A better knowledge of the smell of death and their volatile constituents may have many applications in forensic sciences. Author Affiliation: (a) Department of Functional and Evolutionary Entomology, Gembloux Agricultural University, 2 Passage des Deportes, 5030 Gembloux, Belgium (b) Institut scientifique de service public, Service Qualite de l'Air, 200 Rue du Chera, 4000 Liege, Belgium (c) Institut National de Criminalistique et de Criminologie, Laboratoire Microtraces, 98-100 Chaussee de Vilvorde, 1120 Brussels, Belgium (d) Department of Analytical Chemistry, Gembloux Agricultural University, 2 Passage des Deportes, 5030 Gembloux, Belgium Article History: Received 9 September 2008; Revised 20 March 2009; Accepted 30 March 2009

Isoflavones constitute one of the most common categories of nonsteroidal estrogen-like substances belonging to the broad group of phytoestrogens. The highest concentrations in the plant kingdom are found in the Fabaceae family. They have become a focus of research because of their estrogenic or anti-estrogenic effect and potential impact on human health. In recent years, several studies have focused on the impact of biotic and abiotic factors and farming management on the isoflavone concentration in plants and their impact on the composition of cow’s milk. Nevertheless, knowledge about the effect of the ensiling process on isoflavone concentration remains limited. The objective of this work was to study the evolution of the concentrations of four compounds (daidzein, formononetin, genistein and biochanin A) in red clover ( Trifolium pratense L.) ensiled at harvest. The impact of the field-drying process was also assessed. The plant material was ensiled in laboratory‐scale silos using vacuum-packed plastic bags and stored over a 6-month period. The quality of the silages was checked throughout the experiment by determining the pH, lactic acid concentration, volatile fatty acids, crude proteins, cellulose and other chemical characteristics. The isoflavone concentration in fresh plant material was 2050, 1766, 306 and 127 μg/g DM for formononetin, biochanin A, genistein and daidzein, respectively. After 4 days of drying in the field, no significant change in isoflavone concentration was found, except for daidzein, which increased twofold. The laboratory-scale silos experiment, however, showed a decrease in isoflavone concentration during the first 2 weeks, followed by stabilization over the 5 remaining months. The concentrations fell by 26, 39, 66 and 73% for daidzein, genistein, biochanin A and formononetin, respectively. Animals fed with silage would therefore absorb fewer isoflavones than those fed with fresh plant material or hay. [ABSTRACT FROM AUTHOR]

Interest in the fatty acid composition of dairy products is increasing; however, the measurement of fatty acids requires using gas-liquid chromatography. Although this method is suitable, it involves a time-consuming procedure, expensive reagents, and qualified staff. By comparison, the mid-infrared (MIR) spectrometry method could be a good alternative for assessing the fatty acid profile of dairy products. The objective of this study was to explore the calibration of MIR spectrometry for estimating fatty acid concentrations in milk and milk fat. Estimated concentrations in milk fat were less reliable than those for the same fatty acids in milk. Results also showed that when the fatty acid concentrations in milk increased, the efficiency of the infrared analysis method in predicting these values simultaneously increased. Selected prediction equations must have a high cross-validation coefficient of determination, a high ratio of standard error of cross-validation to standard deviation, and good repeatability of chromatographic data. Results from this study showed that the calibration equations predicting 12:0, 14:0, 16:0, 16:1cis-9, 18:1, and saturated and monounsaturated fatty acids in milk could be used. Thus, with its potential for use in regular milk recording, this infrared analysis method offers the possibility of assessing and improving the quality of milk produced. Indeed, it enables the fatty acid composition in milk to be estimated for each cow and the estimates to be used as indicator traits to determine the genetic values of underlying fatty acid concentrations. The knowledge of these genetic values would open up opportunities for animal selection aimed at improving the nutritional quality of cow milk. [ABSTRACT FROM AUTHOR]

Abstract: In the present study a practical model useful for designers dealing with pilot scale reactors for pollutant control has been developed. Investigations were undertaken for a single-component lead study on New Zealand clinoptilolite at the temperature of 25±1° C. Fifteen runs under different operating conditions such as particle characteristics (expressed as ), column geometry (as ) and flow speed (as R e *) have been performed. The results were interpreted by a response surface method (RSM) from which an equation giving the unused bed zone (UBZ) was obtained. From those dimensionless parameters, a sequence of contour plots was drawn, making it easy for a designer to choose optimum design parameters while controlling the operation performance. The flow rate (R e *) range was established over the laminar flow conditions from 1 to 8, (l/D*) was extended from 7 to 20 and (d p/D*) varied from 3% to 10%. Optimization of performance of the reactor as UBZ could vary from 10% to 40% of the material operating capacity. [Copyright &y& Elsevier]