Fatty acid profile,oxidative stability,and sensory properties of breast meat from turkeys fed diets with a different n‐6/n‐3 PUFA ratio

The objective of this study was to determine the effect of diets with a different n‐6/n‐3 PUFAs ratio (7.31, 4.43, and 0.99), resulting from the addition of different dietary oils: soybean, rapeseed, and linseed (diets S, R, and L, respectively), on the fatty acid (FA) profile, oxidative status, and sensory properties of turkey breast meat. After 15 wk of feeding, breast meat yield and chemical properties of the meat were similar in all groups. Raw breast meat of R turkeys had a significantly higher content of all‐trans‐retinol and α‐tocopherol, compared with S and L. The physicochemical properties of breast meat, including pH, color, drip loss, and cooking loss, did not differ significantly. Cooked meat samples differed significantly with respect to the concentrations of oleic acid, linoleic acid (S and R>L), and linolenic acid (S and R<L). Compared with S and R, breast meat of L turkeys was characterized by higher concentrations of total PUFAs (35.1 vs. 30.1 and 29.3%), a significantly lower n‐6/n‐3 PUFAs ratio (1.51 vs. 5.43 and 5.07%) and a higher thiobarbituric acid reactive substances content (TBARS; 31.9 vs. 26.4 and 26.7 nmol/g). After 4 months of deep‐freeze storage the n‐6/n‐3 PUFAs ratio did not deteriorate. It may be concluded that replacing soybean oil with linseed oil, but not with rapeseed oil, increased the proportion of PUFAs in the total FAs pool and improved the n‐6/n‐3 PUFAs ratio, yet it also adversely affected the sensory properties and oxidative stability of meat. Both raw and stored breast meat from L turkeys was susceptible to oxidative changes, as manifested by the significantly higher TBARS concentrations (17.07 and 81.06) compared with those of the S group (10.91 and 53.00 nmol/g, respectively). Practical applications: Studies investigating the possibility of increasing the health benefits of poultry meat have been performed mostly on broilers, while the problem remains poorly researched in turkeys. Our findings show that linseed oil, in contrast to rapeseed oil, is a good source of PUFAs, in particular n‐3 PUFAs, that can be effectively transferred from feed to carcass lipids. However, desirable changes in the fatty acid profile are accompanied by increased susceptibility to lipid oxidation and deterioration of the sensory properties of meat. Thus, the linseed oil content of turkey diets should be reduced, or diets supplemented with linseed oil should be fed for shorter periods of time to alleviate the negative effects of linseed oil on the sensory attributes and oxidative status of meat.     

Positron Studies of Subsurface Zone Created in Sliding Wear in Bismuth

The report about subsurface zone (SZ) created during dry sliding in pure bismuth is presented. The positron lifetime measurements revealed the well defined subsurface zone where the concentration of created during sliding vacancy clusters decreases exponentially with the depth from the worn surface increases. The experimental results are quite well described by the two state trapping model which allows to determine the positron trapping rate and hence deduce about the depth dependency of vacancy voids concentration. Despite of the low recrystallization temperature ca. 115 °C in this semimetal, determined also by the positron lifetime measurements, no significant effect of temperature rise due to sliding on the SZ constitution is observed.     

Concentrations and bioconcentration factors of minerals in yellow-cracking bolete (xerocomus subtomentosus) mushroom collected in noteć forest, poland

Abstract: Yellow‐cracking Bolete (Xerocomus subtomentosus) mushrooms and soil were collected from Note? Forest–a large forested enclave in western part of Poland. Mercury was determined by cold vapour atomic absorption spectroscopy and the other elements by inductively coupled plasma atomic emission spectroscopy. K, P, and Mg were particularly abundant, with mean values of 46000, 8400, and 1100 mg/kg dry weight (dw) in caps followed by Na, Rb, Zn, and Ca with mean concentrations of 580, 350, 200, and 170 mg/kg dw, respectively. In descending order, the mean concentrations of Fe, Al, Cu, and Mn were 52, 49, 46, and 14 mg/kg dw, while the mean for the remaining elements was around 1.0 mg/kg dw or less. The elements such as Ca, Cu, Hg, K, Mg, Na, P, Rb, Zn, Ag, Cd, and Ni were accumulated (with bioconcentration factor (BCF) > 1), while Al, Ba, Fe, Mn, Sr, Co, Cr, and Pb were excluded (BCF < 1) in the fruiting bodies. The Pb and Cd content did not exceed the maximum levels set by the EU for cultivated mushrooms. Mercury in a conventional meal (300 g) portion of Yellow‐cracking Bolete was far below the provisionally tolerable weekly intake of 0.004 mg/kg body weight (bw) as reevaluated recently by WHO. Practical Application: The method presented in this study allows one to determine the content of 20 elements (Ag, Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Na, Ni, P, Pb, Rb, Sr, and Zn) in caps and stipes of Yellow‐cracking Bolete (Xerocomus subtomentosus) mushrooms and soil samples collected from Poland. This study has revealed that the total Cd, Hg, and Pb dose provided to human body due to consumption of Yellow‐cracking Bolete does not pose threat to a consumer's health.     

A 1.1 V 6.2 mW,wideband RF front-end for 0 dBm blocker tolerant receivers in 90 nm CMOS

This paper presents the design and implementation of a low power, highly linear, wideband RF front-end in 90 nm CMOS. The architecture consists of an inverter-like common gate low noise amplifier followed by a passive ring mixer. The proposed architecture achieves a high linearity in a wide band (0.5–6 GHz) at very low power. Therefore, it is a suitable choice for software defined radio (SDR) receivers. The chip measurement results indicate that the inverter-like common gate input stage has a broadband input match achieving S11 below −8.8 dB up to 6 GHz. The measured single sideband noise figure at an LO frequency of 3 GHz and an IF of 10 MHz is 6.25 dB. The front-end achieves a voltage conversion gain of 4.5 dB at 1 GHz with 3 dB bandwidth of more than 6 GHz. The measured input referred 1 dB compression point is +1.5 dBm while the IIP3 is +11.73 dBm and the IIP2 is +26.23 dBm respectively at an LO frequency of 2 GHz. The RF front-end consumes 6.2 mW from a 1.1 V supply with an active chip area of 0.0856 mm².     

Field Effect Transistors for Terahertz Detection: Physics and First Imaging Applications

Resonant frequencies of the two-dimensional plasma in FETs increase with the reduction of the channel dimensions and can reach the THz range for sub-micron gate lengths. Nonlinear properties of the electron plasma in the transistor channel can be used for the detection and mixing of THz frequencies. At cryogenic temperatures resonant and gate voltage tunable detection related to plasma waves resonances is observed. At room temperature, when plasma oscillations are overdamped, the FET can operate as an efficient broadband THz detector. We present the main theoretical and experimental results on THz detection by FETs in the context of their possible application for THz imaging.     

Single molecular switch based on thiol tethered iron(II)clathrochelate on gold

Molecular electronics has been associated with high density nano-electronic devices. Developments of molecular electronic devices were based on reversible switching of molecules between the two conductive states. In this paper, self-assembled monolayers of dodecanethiol (DDT) and thiol tethered iron(II)clathrochelate (IC) have been prepared on gold film. The electrochemical and electronic properties of IC molecules inserted into the dodecanethiol monolayer (IC-DDT SAM) were investigated using voltammetric, electrochemical impedance spectrpscopy (EIS), scanning tunneling microscopy (STM) and cross-wire tunneling measurements. The voltage triggered switching behaviour of IC molecules on mixed SAM was demonstrated. Deposition of polyaniline on the redox sites of IC-DDT SAM using electrochemical polymerization of aniline was performed in order to confirm that this monolayer acts as nano-patterned semiconducting electrode surface.     

Two-dimensional modelling of deposits formation on platen superheaters in pulverized coal boilers

The 1D modeling of deposits formation is not able to describe properly the gas and particles flow in the vicinity of heat transfer tubes in boilers. Especially, the recirculation zones in the down-stream side of tubes are not possible to reproduce by the 1D models. Known applications of the CFD codes to deposition modelling were able to reproduce only the rate of particles deposition on surfaces, while for practical reasons the most important information is the shape and size of deposits, because it enables prediction of heat transfer abatement with boiler operation time. Paper presents 2D modelling of deposits on platen superheaters in pulverized coal boilers. Particularly, the observed in industrial boilers bridging of the tubes spacing was reproduced by the model in which the particle size dependence of the ash sticking probability was proposed. It has been demonstrated that the ash particles size play important role in the deposits growth mechanism.     

Discovery by Minimal Length Encoding: A Case Study in Molecular Evolution

We apply the Minimal Length Encoding Principle to formalize inference about the evolution of macromolecular sequences. The Principle is shown to imply a combination of Weighted Parsimony and Compatibility methods that have long been used by biologists because of their good practical performance. The background assumptions are expressed as an encoding scheme for the observed data and as heuristic rules for selection of diagnostic positions in the sequences. The Principle was applied to discover new subfamilies of Alu sequences, the most numerous family of repetitive DNA sequences in the human genome.