Bioaccumulation of dioxin-like substances and selected brominated flame retardant congeners in the fat and livers of black pigs farmed within the Nebrodi Regional Park of Sicily

An observational study was designed to assess the bioaccumulation of polychlorodibenzodioxins (PCDD) and polychlorodibenzofurans (PCDF), dioxin-like polychlorobiphenyls (DL-PCB), and 13 selected polybromodiphenylethers (PBDE) in autochthonous pigs reared in the Nebrodi Park of Sicily (Italy). Perirenal fat and liver samples were drawn from animals representative of three different outdoor farming systems and from wild pigs and then analyzed for the chemicals mentioned previously. The highest concentrations of PCDD + PCDF and DL-PCB were detected in the fat (0.45 and 0.35 pg World Health Organization toxicity equivalents [WHO-TE] per g of fat base [FB], respectively) and livers (12.7 and 3.28 pg WHO-TE per g FB) of the wild group, whereas the free-ranging group showed the lowest levels (0.05 and 0.03 pg WHO-TE per g FB in fat and 0.78 and 0.27 pg WHO-TE per g FB in livers). The sum of PBDE congeners was highest in wild pigs (0.52 ng/g FB in fat and 5.64 ng/g FB in livers) and lowest in the farmed group (0.14 ng/g FB in fat and 0.28 ng/g FB in livers). The contamination levels in fat and livers of outdoor pigs had mean concentration values lower than those levels reported for intensively indoor-farmed animals. In wild pigs, bioaccumulation was associated with their free grazing in areas characterized by bush fires. The results of this study aid to emphasize the quality of the environment as a factor to guarantee food safety in typical processed pig meat products, specifically from outdoor and extensive Nebrodi farming systems.     

Comparison of nutritional and nutraceutical properties in cultivated fruits of Fragaria vesca L. produced in Italy

Individual sugars, organic acids, total polyphenols, vitamin C and antiradical activity (as measured by DPPH method) were quantified in cultivated Fragaria vesca berries, comparing different varieties (Regina delle Valli, Alpine, Sara and Valitutto) and different environments with regard to altitude. Cultivar effect mainly influenced the concentration of total polyphenols and antiradical activity which are strongly correlated (R² = 0.91; P = 0.001); conversely, altitude seemed to exert an influence in sugar and organic acid composition. The comparison of the general quality of the most diffused cultivar of F. vesca (Regina delle Valli and Alpine) evidenced that both cultivars have the same nutritional properties, whereas Regina delle Valli is better than Alpine from the point of view of total polyphenolic content (716 vs 471 mg catechin/100 g fresh weight) and radical scavenging activity (301 vs 219 ml DPPH solution/100 g fresh weight), thus resulting more attractive from the health protecting attributes point of view. F. vesca berries showed also a concentration of sugars, citric acid, malic acid and total polyphenols much higher than those reported in literature for Fragaria x ananassa.     

A theoretical analysis of a buffer frame size conversion algorithm for audio applications ensuring minimum latency

In implementing digital signal processing (DSP) algorithms for audio real-time applications, one is frequently faced with problems regarding incompatibilities between the hardware buffer length (the internal buffer of a professional sound card) and the software buffer size imposed by the underlying algorithm (due to i.e. multirate or FFT constraints). This mismatch is solved by proper frame size conversion algorithms which inevitably introduce delay. In this context, this paper presents a buffering scheme together with a theoretical proof of the minimum delay property shown by it. Some examples derived from frequently encountered issues in DSP applications are reported.     

Moisture-induced stresses perpendicular to grain in cross-sections of timber members exposed to different climates

In variable humidity conditions, wood absorbs or desorbs moisture from the air. Unless the change in humidity is very slow, this will develop moisture gradients in the wood sections. These gradients will develop stresses due to constrained swelling or shrinkage strains. These stresses are named moisture-induced stresses. The present paper investigates the main parameters affecting such moisture-induced stresses, including the type of climate, the size of the timber cross-section, and the type of protective coating. A first attempt to identify moisture-induced stresses in different European climatic regions was made. For each climatic region, relative humidity and temperature histories were identified, and characteristic and mean values of yearly and daily variations were calculated. Using a finite element model implemented in Abaqus, the moisture content and stress distribution were computed on different timber cross-sections exposed to the climatic regions and protected with different types of coating. A Fickian moisture transfer model was used to compute the moisture distribution, and a mechanical model for time-dependent behaviour of wood was implemented to calculate the corresponding stress distribution. The variation of moisture was found to result in stresses of magnitudes that would probably cause cracking of wood in the perimeter of any uncoated cross-section size. The use of a protective coating, however, reduced considerably the moisture-induced stresses, and can be regarded as an effective protective measure to avoid cracking due to humidity variations. Considering European climates, Northern climates were found to result in higher surface tensile stresses than Southern climates.     

Static analysis of a Bickford beam by means of the DQEM

In this paper the recently proposed differential quadrature element method is employed in order to solve the equilibrium equations of a higher-order beam. A simple five-node element is introduced, in which the vertical displacement is approximated by a sixth-order polynomial, whereas the rotation is consistently approximated by a fourth-order polynomial, and the resulting weighting coefficient matrix is given. Moreover, a general procedure is outlined, for an N-node element, in which vertical displacements and rotations are given by polynomials of order N+1 and N-1, respectively. Numerical examples are aimed both at checking the convergence of the results for increasing values of the nodes, and at comparing the used cubic beam theory with the simpler, linear, Timoshenko theory.     

Use of compatible blends to fabricate carbon black composite vapor detectors

The aim of this work was the development of materials to be used in the field of gas sensing for the detection of organic vapors. Conductive sensors were prepared with carbon black filled blends of poly(vinyl chloride) and diol‐terminated poly(?‐caprolactone), an oligomeric plasticizer. For comparison, blends with di(2‐ethylhexyl)phthalate, a traditional low‐molecular‐weight plasticizer, were also prepared. All sensors were tested upon exposure to different organic vapors. In general, the plasticizer content affected the response rates of the sensors, and a linear variation of the relative resistance with the analyte concentration was observed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1816–1821, 2004     

Molecular characterization of Italian rice cultivars

Random amplified polymorphic DNA (RAPD) is an efficient tool to detect DNA polymorphisms and to distinguish different clones and cultivars. We have applied the RAPD technique to distinguish, starting from a single rice seed, among some Italian rice cultivars from market and from National Institute for research on food and nutrition, Italy. We also estimated the genomic similarity among the rice cultivars object of this study taking advantage of the amplification patterns. Despite the low genomic variability among Italian rice cultivars, RAPD technique allowed us to distinguish among them. This indicates that RAPD can be used routinely to verify the identity of Italian rice cultivars in order to prevent fraudulent commercial activity.     

Content of phytoestrogens in soy-based dietary supplements

The isoflavone content of 14 soy-based dietary supplements intended to help alleviate perimenopausal and menopausal symptoms on sale in Italy were analysed using HPLC with UV detection. The aim was to quantify soy isoflavones after hydrolysis as aglycones, which are the bioactive part of isoflavone molecules. In the examined products, the amounts of isoflavones were frequently expressed ambiguously, and none of the products stated whether the isoflavone content of the product was expressed as aglycones or as conjugates. Each product revealed a different aglycone concentration profile. These supplements have different “fingerprints”, probably due to different sources of raw materials and to methods used in processing and preparation of extracts. In more than half the supplements tested, the actual values contained were below those stated and below those expected to help alleviate perimenopausal and menopausal symptoms.     

Adsorption equilibria of benzodiazepines on a hybrid polymeric chiral stationary phase

The chromatographic behavior of a series of racemic benzodiazepines was evaluated under linear and nonlinear conditions on a new hybrid polymeric (DACH-ACR) chiral stationary phase (CSP). Differently substituted benzodiazepines were employed as probes to make hypotheses concerning possible molecular interaction mechanisms originating between target compounds and active sites on the CSP. Hydrogen bonds were found to be pivotal for chromatographic retention and chiral selectivity. The competitive effect from a mobile-phase (MP) modifier able to interact with the CSP through H-bonds was investigated. The performance of the polymeric DACH-ACR CSP for preparative purposes was also evaluated. The competitive adsorption isotherms of two benzodiazepines, lorazepam and temazepam, were measured at different MP compositions through the so-called inverse method. The adsorption data were fitted with a competitive bi-Langmuir adsorption isotherm. Enantiomeric separations under nonlinear conditions were modeled by using the equilibrium dispersive (ED) model of chromatography. Theoretical overloaded band profiles (obtained by solving the system of partial differential equations described by the ED model) matched, in a significantly accurate way, the profiles experimentally measured.