High resolution two-dimensional electrophoresis as a tool to differentiate wild from farmed cod (Gadus morhua) and to assess the protein composition of klipfish

Tris and CHAPS–urea extracts from wild and farmed cod muscle and from rehydrated cod klipfish fillets were analyzed by one (1DE) and two-dimensional electrophoresis (2DE). 2DE maps of tris extracts from farmed cod differed from the wild in a series of spots of Mw 35 and 45 kDa. The CHAPS–urea extracts from farmed cod had a several spots of Mw between 100 and 45 kDa, which were hardly detectable in wild cod and very prominent in klipfish. Klipfish was clearly different from the other samples: the myosin heavy chain was hardly detectable in these samples, and the tris extracts contained fewer, and the CHAPS–urea more spots than the corresponding extracts from the raw muscles. Further identification of these potentially diagnostic spots will make it easier the differentiation of farmed from wild cod and the evaluation of klipfish processing on the protein content of the product.     

The impact of the exterior painted thin-layer render’s water vapour and liquid water permeability on the moisture state of the wall insulating system

The paper aims at the determination of the possible limits of vapour resistance and liquid water permeability alteration in the case of the exterior painted thin-layer render finish of the building walls from outside insulated with the mineral wool slabs when exploited in the area of cold and humid climate that could guarantee a normal moisture state of the wall insulating system. The moisture testing of the insulating system’s fragments was carried out in the climatic chamber, where the climatic parameters were modelled on the basis of the climatic typical of Lithuania. Thin-layer render was coated with acrylic paints. When the thickness of the paint coating on thin-layer render was increased from 0.08 mm to 0.24 mm, the liquid water absorption coefficient decreased by 59% and vapour resistance increased by 43%. It has also been determined that in the double-layer system paint coating – thin-layer render condensation moisture will be accumulated when the thickness of the air layer s_d equivalent to the material’s water vapour permeability is higher than 0.6 m. Rain will have an impact on the wall’s moisture state, when the liquid water absorption coefficient w of the double-layer system paint coating – thin-layer render is higher than 0.025 kg/(m² h^0.5). The micro-lens discovered in the areas of moisture accumulation by the thermographic analysis should be considered as the rudiments of the defect formation in the exterior insulating system.     

Transformation of Vegetable Oils into Hydrocarbons over Mesoporous-Alumina-Supported CoMo Catalysts

Deoxygenation of triglycerides over organized-mesoporous-alumina-supported CoMo catalysts (CoMo/OMA) has been investigated in this work. CoMo/OMA catalysts exhibited higher activity for deoxygenation of triglycerides than CoMo supported on MCM-41 (silica) and ordinary alumina supports. Two main deoxygenation pathways were found: hydrodeoxygenation and hydrodecarboxylation. Their extent was affected by reaction temperature, pressure and the support used. Hydrodeoxygenation was the main reaction under the studied conditions. The extent of hydrodecarboxylation increased with increasing reaction temperature and decreasing reaction pressure.     

Content of polyamines in beef and pork after animal slaughtering

Dietary polyamines putrescine (PUT), spermidine (SPD) and spermine (SPM) participate in an array of important human physiological roles, including tumour growth. Physicians and dieticians thus need reliable information on polyamine contents in foods. However, data for both fresh and processed beef and pork are limited. We therefore, determined the initial content of the polyamines, 24 h after slaughtering, in sirloin and rump of 63 young bulls and in loin and leg of 27 pigs of both genders. Polyamines were determined as N-benzamides by micellar electrokinetic capillary chromatography (MECC). PUT and SPD contents in most of the meat samples were negligible. Mean SPM contents were about 22±6 mg kg⁻¹ in sirloin and rump. No significant correlations at P<0.05 were found between the SPM contents in sirloin and rump, likewise between SPM contents and the age and between live weight and type of the efficiency of the bulls. Mean SPM contents in loin and legs of barrows were 26.1±7.0 and 28.4±8.5 mg kg⁻¹, respectively, while the corresponding values in gilts were 22.3±10.6 and 18.3±9.3 mg kg⁻¹.Between the genders the difference in SPM contents in the legs was significant. SPM contents relatively vary widely within the individual kinds of meat, which complicates application of the results for the controlled human nutrition.     

High-alumina porcelain with the addition of a Li2O-bearing fluxing agent

We have studied the influence of increasing the amount of β-spodumene (LiAlSi₂O₆), as a Li₂O-containing flux, on the phase composition, the microstructure evolution and the physical properties of high-alumina porcelain. Quartz reacts with β-spodumene in the temperature range 1150–1250 °C, forming lithium aluminium silicates with a larger amount of SiO₂. The presence of lithium minerals contributes to a lower CTE for the fired bodies. At 1300 °C an improved flexural strength is achieved with compositions containing 1.0 or 1.2 wt.% of Li₂O, as a result of a more uniform microstructure. With increasing amounts of Li₂O the overfiring effect is greatly enhanced. The most favourable characteristics from an industrial perspective with regard to flexural strength and deformation during firing were attained by using a high-alumina porcelain composition containing 1.0 wt.% Li₂O.     

Numerical modeling of TeraHertz electronic devices

We investigate by means of Monte Carlo simulations the physical processes associated with the emission of TeraHertz radiation in different electronic devices. We analyze four alternative and complementary strategies which seem to be promising candidates to obtain the TeraHertz emission: (1) a nitride maser based on the optical-phonon transit-time resonance, (2) the high–order harmonic generation in bulk materials and nanometric Schottky-barrier diodes, (3) the excitation of coherent plasma oscillations in micron and submicron diodes, (4) the current instabilities and plasma oscillations in high electron mobility transistors (HEMT). The numerical results show that several physical mechanisms can be exploited to increase significantly the operating frequency of these devices and the best conditions to optimize the radiation emission in the TeraHertz range are studied in detail.     

Effect of electrolyte movement and composition on corrosion of passive aluminium

The flow of a corrosive medium accelerates corrosion of aluminium especially in solutions of medium alkalinity, to an extent dependent on the character of the anions involved (carbonate, borate, phosphate). Within this region of transport control of the corrosion rate in the passive state, the aluminate ion as a reaction product probably takes a part in controlling the reaction. In strongly acid and alkaline solutions the transport phenomena have only a negligible effect on the rate of corrosion.     

Supercritical carbon dioxide extraction of carrot fruit essential oil: Chemical composition and antimicrobial activity

Isolation of carrot fruit (Daucus carrota L., cultivar “Chanteney”) essential oil by supercritical carbon dioxide was investigated from the pretreatment of herbaceous matrix and extraction conditions to the chemical composition of obtained extract and its antimicrobial activity. The qualitative and quantitative analyses of the supercritical extract, as well as of the essential oil obtained by hydrodistillation, were done by GC/FID and GC/MS methods. Antimicrobial properties of both samples were investigated against ten species of microorganisms. Experimental results showed that the particle size had no influence on the extraction process. The highest yield was obtained at 40 °C and 10 MPa. The main component of the supercritical extract, as well as of the essential oil was carotol. The supercritical extract was characterized by the presence of heavier molecular weight compounds, while some lighter compounds, e.g. pinenes, were not detected. The supercritical extract and the essential oil were the most effective against Gram-positive bacteria.     

Bioelectrical resistance and its seasonal variation as the indicator of tree condition as illustrated by silver fir (Abies alba Mill.)

European Journal of Wood and Wood Products -