Inhibitory effect of organic acids on arcobacters in culture and their use for control of Arcobacter butzleri on chicken skin

The inhibitory effects of 17 organic acids (C₂-C₁₆ fatty acids, sorbic, benzoic, phenylacetic, fumaric, succinic, lactic, malic and citric) on Arcobacter butzleri, Arcobacter cryaerophilus and Arcobacter skirrowii were investigated by determining their IC₅₀ values, defined as the concentration of acid at which the target DNA sequence was expressed at 50% of the positive control level in cultures incubated at 30 °C for 24 h. DNA was analysed by real-time PCR. The Arcobacter strains tested were inhibited by all the organic acids, with the sensitivities in the order A. skirrowii > A. cryaerophilus > A. butzleri. Eight acids with IC₅₀ values of < 1 mg/mL against A. butzleri were tested for their effects on A. butzleri inoculated on chicken carcasses at a concentration of 5 log CFU/g of skin. Inoculated halved carcasses were immersed in solutions of the acids at 5 mg/mL for 1 min. Samples of skin were collected from carcass halves after storage at 4 °C for 0, 1, 2 or 3 days for enumeration of arcobacters on Muller-Hinton agar. All eight tested acids suppressed bacterial proliferation. The highest inhibitory activities were observed for benzoic, citric, malic and sorbic acids. Subsequent sensory analysis revealed benzoic acid to be the most suitable organic acid for chicken skin treatment.     

Chemical,technological, and nutritional characteristics of two lines of “farro” (Triticum turgidum ssp. dicoccum)

In recent years, the renewed interest for foods with a natural image has increased the demand for dry pasta produced from “hulled” wheat such as the Triticum turgidum ssp. dicoccum, also known as “farro”. In order to contribute to the general knowledge, two lines of farro were considered in this study. To have a comparison, an old cultivar of Triticum turgidum ssp. durum (Senatore Cappelli) in addition to a commercial semolina were also examined. All semolina samples were used to produce pasta samples. Results showed some differences among pasta samples that seem to be due not to the presence of specific protein subunits but especially to the quantitative ratio between the different subunits. Results also reconfirmed the role played by the drying technology that is able to affect the sensory characteristics of pasta products.     

A Peltier cells differential calorimeter with kinetic correction for the measurement of cp(H,T) and Δs(H,T) of magnetocaloric materials

In this paper we describe and test a setup for the characterization of the magnetocaloric effect around room temperature. The setup is a differential calorimeter able to measure both the specific heat c(p)(H,T) under constant magnetic field H and the isothermal entropy change induced by changing H, Δs(H,T), in the room temperature range. The setup uses miniaturized Peltier cells to measure the heat flux, with resolution of about 1 μW, and power Peltier cells to regulate the temperature in the range from 243 K (-30 °C) to 343 K (+70 °C). The kinetic effects due to the heat capacity of the measuring cells are taken into account by a simple model of the heat flux diffusion in the calorimetric cell. As measurement examples, we show the characterization of the magnetocaloric effect in magnetic materials with a second order transition [without latent heat and without hysteresis, as in the La(1)(Fe(1-x-y)Co(y)Si(x))(13) alloy with x=0.077 and y=0.079] and with a first order transitions (with latent heat and hysteresis as in Ni(50)Mn(36)Co(1)Sn(13)). As a result we compare the entropy change Δs(H,T) derived from (i) the integration of the specific heat c(p)(H,T) and (ii) the direct isothermal measurements, obtaining an excellent agreement.     

Spectral calibration of radiometric detectors using tunable laser sources

This paper describes the analysis of laser-based responsivity measurements using the Tunable Lasers in Photometry setup at the Physikalisch-Technische Bundesanstalt. An approach based on digital signal analysis is proposed to remove interference-caused oscillations in highly resolved spectral data from laser-based measurements, yielding an improved reproducibility and comparability of results. Digital filters are used to selectively suppress the frequency components of interference fringes visible in the measurement data. We describe the algorithm used and discuss the associated uncertainty components of laser-based measurements. Finally, we give examples of the calibration of different detectors with and without interference effects.     

Genotypic and climatic influences on the concentration and composition of flavonoids in kale (Brassica oleracea var. sabellica)

The aim of this study was to determine the composition and concentration of flavonoid aglycones in kale, the dependence on genotype and their interaction with decreasing temperature and global radiation. Eight kale cultivars, comprising hybrid and traditional, old cultivars, were grown in a field experiment and harvested four times at 4-week intervals. The traditional, old cultivars in particular contained high concentrations of flavonoids. In all of the investigated cultivars, kaempferol was the main flavonoid aglycone, followed by quercetin and isorhamnetin, which was quantified in six of the eight cultivars. Furthermore, in six of the eight cultivars, the total concentration of flavonoids remained unchanged with decreasing temperature and global radiation. The quercetin concentration increased in five of these six cultivars, whereas the kaempferol concentration decreased. Interestingly, the quercetin-to-kaempferol ratio increased in all of the investigated cultivars, despite the fact that the radiation level decreased, suggesting that the impact of the decline in temperature could be responsible for this effect.     

Genome engineering allows selective conversions of terephthalaldehyde to multiple valorized products in bacterial cells

Deconstruction of polyethylene terephthalate (PET) plastic waste generates opportunities for valorization to alternative products. We recently designed an enzymatic cascade that could produce terephthalaldehyde (TPAL) from terephthalic acid. Here, we showed that the addition of TPAL to growing cultures of Escherichia coli wild-type strain MG1655 and an engineered strain for reduced aromatic aldehyde reduction (RARE) strain resulted in substantial reduction. We then investigated if we could mitigate this reduction using multiplex automatable genome engineering (MAGE) to create an E. coli strain with 10 additional knockouts in RARE. Encouragingly, we found this newly engineered strain enabled a 2.5-fold higher retention of TPAL over RARE after 24 h. We applied this new strain for the production of para-xylylenediamine (pXYL) and observed a 6.8-fold increase in pXYL titer compared with RARE. Overall, our study demonstrates the potential of TPAL as a versatile intermediate in microbial biosynthesis of chemicals that derived from waste PET.     

Neural networks for model-free and scale-free automated planning

Knowledge and Information Systems - Automated planning for problems without an explicit model is an elusive research challenge. However, if tackled, it could provide a general approach to problems...     

The Role of the LINC Complex in Sperm Development and Function

The LINC (LInker of Nucleoskeleton and Cytoskeleton) complex is localized within the nuclear envelope and consists of SUN (Sad1/UNc84 homology domain-containing) proteins located in the inner nuclear membrane and KASH (Klarsicht/Anc1/Syne1 homology domain-containing) proteins located in the outer nuclear membrane, hence linking nuclear with cytoplasmic structures. While the nucleoplasm-facing side acts as a key player for correct pairing of homolog chromosomes and rapid chromosome movements during meiosis, the cytoplasm-facing side plays a pivotal role for sperm head development and proper acrosome formation during spermiogenesis. A further complex present in spermatozoa is involved in head-to-tail coupling. An intact LINC complex is crucial for the production of fertile sperm, as mutations in genes encoding for complex proteins are known to be associated with male subfertility in both mice and men. The present review provides a comprehensive overview on our current knowledge of LINC complex subtypes present in germ cells and its central role for male reproduction. Future studies on distinct LINC complex components are an absolute requirement to improve the diagnosis of idiopathic male factor infertility and the outcome of assisted reproduction.     

Eco-Friendly Natural Clay: Montmorillonite Modified with Nickel or Ruthenium as an Effective Catalyst in Gamma-Valerolactone Synthesis

Catalysis Letters - Ni/Ru metals supported on cheap and available support montmorillonite K10 were used for the selective hydrogenation of levulinic acid to γ-valerolactone. Different loadings...