Quality and nutritional characteristics of traditional curd cheese enriched with thermo-coagulated acid whey protein and indigenous Lactococcus lactis strain

Consumer interest in a healthy lifestyle and health-promoting natural products is a major driving force for the increasing global demand for bio-functional and sustainable dairy foods. Supplementation of curd cheese with thermo-coagulated acid whey protein (TAWP) led to 8–10% higher contents of moisture, 23–31% of lactose, 12–13% of unsaturated, 5–6% of monounsaturated, 63% of polyunsaturated, and 3–4% of long-chain fatty acids. Lipid quality indices – TI, AI, h/H, and Omega 6/3 among others, were also significantly better than those of control cheese. The addition of indigenous Lactococcus lactis strain enhanced the flavour of cheese samples, decreased the counts of yeast and mould up to 1 log cfu g⁻¹ after 10 days of storage. The replacement of curd with TAWP resulted in novel cheese with overall sensory perception above 77 points and added nutritional and functional value, however, body and texture parameters of modified cheese samples require an improvement.     

A topic network analysis of the system turn in the environmental sciences

Scientometrics - The concept of Earth system science denotes a shift in the scientific discourse from disciplinary accounts of isolated components of the global environment towards the holistic and...     

A Critical Assessment of Experimental Methods for Determining the Dynamic Mechanical Characteristics of Shape Memory Polymers

Experimental study of temperature‐ and frequency‐dependent properties of the commercially available shape memory polymer Tecoflex? EG 72D (TFX) (Lubrizol, USA) using dynamic mechanical analysis (DMA) technique is presented. Temperature scan DMA tests have been carried out in three distinct deformation modes, uniaxial tension, three‐point bending, and simple torsion, using two different testing rigs at different test parameters (frequency, strain amplitude, and heating rate) in temperatures ranging from below to above the glass transition temperature. The influence of different test parameters and some discrepancies in the temperature‐dependent storage and loss moduli (and hence the loss factor) measured by DMA in different deformation modes are discussed.     

A graded-gap detector of ionizing radiation

The current response of Al_xGa_1−x As graded-gap layers to optical and X-ray radiation was studied. A graded-gap electric field in the 15-μm-thick Al_xGa_1−x As layers, with x varying from 0 to 0.4, ensures the complete collection of charges generated by ionizing radiation and makes it possible to attain the value of 0.25 A/W for the current-power sensitivity of Al_xGa_1−x As. In the layers with a lowered doping level of the narrow-gap region of the graded-gap Al_xGa_1−x As layer, the voltage-power sensitivity to X-ray radiation with energy lower than 15 keV is as high as 1.6×10³ V/W in the photovoltaic mode. __________ Translated from Fizika i Tekhnika Poluprovodnikov, Vol. 36, No. 1, 2002, pp. 124–128. Original Russian Text Copyright ? 2002 by J. Požela, K. Požela, Šilėnas, Jasutis, Dapkus, Kinduris, Jucienė.     

Genetic diversity of phalaris arundinacea populations in relation to river regulation in the Merkys basin,Lithuania

During the 1950s–1960s, the Merkys river basin, the largest protected area of Lithuania, underwent severe anthropogenic regulations. Within the Baltic States, the genetic diversity of Phalaris arundinacea populations is unknown and how they might be affected by anthropogenic activities such as river regulation. The objectives of this study were to compare molecular parameters (SSRs or microsatellite loci) within and among populations from natural river fragments with populations from regulated river parts. Study populations have greater genetic diversity within, rather than among, populations. The upstream portion of the Merkys basin populations had lower genetic diversity compared with further downstream. The mean number of polymorphic SSR loci was lower for populations from regulated parts of the river basin compared with natural ones. Main principle coordinate analysis revealed populations of regulated rivers at marginal positions. Bayesian clustering showed that current populations are admixtures of 3 distinct genetic groups, based on STRUCTURE analysis (K = 3 groupings) in geographic subdivisions of (a) downstream populations (Var?n?, Verseka, Upper Grūda, Lower Grūda, Upper Merkys, Lower Merkys), (b) upstream populations (Upper ?al?ia, Ber??, Lower ?al?ia, Visin?ia, Lower ?altyk??ia, Nedil?), and (c) the 2 regulated sites in the distinct geographic area of Taurupis and Upper ?altyk??ia. P. arundinacea in the Merkys river basin does not all belong to a single, random‐mating population encompassing its tributaries or among populations across its geographic scales. In several instances, river regulation might impair the genetic diversity of P. arundinacea populations.     

LED lighting and seasonality effects antioxidant properties of baby leaf lettuce

We report on the application of supplementary light-emitting diode (LED) lighting within a greenhouse for cultivation of red, green and light green leaf baby lettuces (Lactuca sativa L.) grown under natural illumination and high-pressure sodium (HPS) lamps (16-h; PPFD-170 μmol m⁻² s⁻¹) during different growing season. Supplementary lighting from blue 455/470 nm and green 505/530 nm LEDs was applied (16-h; PPFD-30 μmol m⁻² s⁻¹). Our results showed that to achieve solely a positive effect is complicated, because metabolism of antioxidant properties in lettuce depended on multicomponent exposure of variety, light quality or seasonality. The general trend of a greater positive effect of supplemental LED components on the vitamin C and tocopherol contents was in order: 535 > 505 > 455 > 470 nm; on the total phenol content: 505 > 535 = 470 > 455 nm; on the DPPH free-radical scavenging capacity: 535 = 470 > 505 > 455 nm; on the total anthocyanins: 505 > 455 > 470 > 535 nm. Further investigations are needed for understanding the mechanism and interaction between antioxidants and light signal transduction pathways.     

Polyacrylamide gels with ionized functional groups in their selective recognition of trimeric molecular form of human growth hormone

Networks of polyacrylamide with ionized functional groups were studied for the possibility of imprinting of oligomeric form of human growth hormone (hGH). Trimeric molecular form of hGH was molecularly imprinted for the first time. The results show that approximately 35–40 % (w/w) of the templates (depending on polymerization conditions) could be extracted from the molecularly imprinted acrylamide polymers. Artificial gel antibodies against trimeric hGH in the form of granules of hydrogel were compared with granules of non-imprinted polymer. Investigation of the binding to imprinted polymer of the template hormone, other molecular forms of the hormone, and other proteins shows enough high selectivity of artificial gel antibodies.     

Feasibility of CHP-plants with thermal stores in the German spot market

The European Energy Exchange (EEX) day ahead spot market for electricity in Germany shows significant variations in prices between peak and off-peak hours. Being able to shift electricity production from off-peak hours to peak hours improves the profit from CHP-plant operation significantly. Installing a big thermal store at a CHP-plant makes it possible to shift production of electricity and heat to hours where electricity prices are highest especially on days with low heat demand. Consequently, these conditions will have to influence the design of new CHP-plants. In this paper, the optimal size of a CHP-plant with thermal store under German spot market conditions is analyzed. As an example the possibility to install small size CHP-plant instead of only boilers at a Stadtwerke delivering 30,000 MW h-heat for district heating per year is examined using the software energyPRO. It is shown that, given the economic and technical assumptions made, a CHP-plant of 4 MW-el with a thermal store participating in the spot market will be the most feasible plant to build. A sensitivity analysis shows to which extent the optimal solution will vary by changing the key economic assumptions.     

Investigation of the changes in physical properties of PES/PVC fabrics after aging

The aim of this work was to investigate the physical and mechanical performance of architectural polyester (PES)–poly(vinyl chloride) (PVC) membranes exposed to different artificial aging conditions. Two commercially available architectural membranes were chosen as research objects. The durability of the PES/PVC fabrics was evaluated by the loss in mechanical performance, scanning electron microscopy, and X-ray diffraction analysis in order to understand the effect of the degradation agents on the surface of the membranes. The mechanical performance of the PES/PVC membranes was unchanged. Scanning electron microscopy images of the tested materials showed initial cracks after aging. The X-ray fluorescence analysis showed that at the time of aging, the amount of Cl and Si decreased slightly, while Ti decreased by half, and Ca by volume increased twice. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47523.