Biological activity and chemical composition of different berry juices

Total phenolics, total anthocyanins, mineral content, radical scavenging activity and antiproliferative activity against human cancer cell lines were evaluated in fresh pressed juices of five different berries. Total phenolic content ranged from 133.0 to 260.3 mg of gallic acid equivalents/100 g of fresh weight, for red currant and black currant, respectively. Bilberry juice contained the highest amount of total anthocyanins (0.18%). Significant correlation between total phenolics content and radical scavenging activity was observed (r = −0.980; p < 0.01). All examined juices showed antiproliferative activity in dose-dependent manner with IC₅₀ ranging from 10.2 to 70.5 μl/ml. Black currant juice was the most effective inhibitor of proliferation in all cell lines tested (HeLa, Fem X, LS 174, MCF-7 and PC-3). Significant correlations of acidity and total anthocyanin content with antiproliferative activity of berry juices on HeLa cells, Fem X cells and MCF-7 cells were noticed. Berry juices are good sources of some minerals and contribute significantly to daily intake of these micronutrients.     

Adjustment of Planning Practice to the New Eastern and Central European Context

The urban planning profession and its activities in Eastern and Central Europe have been affected by the political and economic transformation in these countries. The new, still evolving societal and institutional frameworks present urban planners with a highly dynamic context to which they must adapt. In contrast to relatively predictable centrally planned and controlled development, the cities there are now subjected to multiple forces and immense pressures on their already fragile environments. This article reviews the frameworks, trends, and issues that characterize the planning practice in this transitional period as evidenced in the capital cities of Prague, Bratislava, and Budapest. Planners in the U.S. and Western Europe will find many of these topics relevant to past, present, and future circumstances they face. The article provides for mutual learning and exchange of experiences, and for better understanding and improvement of planning systems and practice. It relates to the core dilemma in justifying planning as government intervention vis-a-vis free market rule.     

Impact of ultrasound on egg white proteins as a pretreatment for functional hydrolysates production

The objective of this study was to investigate the effects of different ultrasound pretreatment on enzymatic hydrolysis of egg white proteins (EWPs) by Alcalase as well as evaluating some functional and antioxidant properties of hydrolysates obtained by various proteases treatment and ultrasound technology. The effects of chosen ultrasound pretreatment parameters including frequency of ultrasonic waves (35 and 40 kHz), temperature (25 and 55 °C), time of pretreatment (15–60 min) and pH of egg white solution (7.00–10.00) were examined. It appeared that controlled ultrasound treatment can improved the hydrolysis process compared with untreated samples, but optimization of the power and length of sonication was important. The optimal ultrasound pretreatment at calorimetric power of 21.3 W and frequency of 40 kHz for 15 min at 25 °C and with naturally basic egg white (pH 9.25) resulted in increased initial rate and equilibrium degree of Alcalase hydrolysis by about 139.8 and 13.86 % compared with the control, respectively. EWP hydrolysates with ≈27.0 % degree of hydrolysis obtained with heat pretreatment and ultrasound pretreatments under optimal conditions were further separated by sequential ultrafiltration into 4 hydrolysate fractions (<1, 1–10, 10–30 and >30 kDa) which were investigated for protein content, peptide yield and antioxidant activity. The hydrolysis after heat pretreatment generated more peptides <1 kDa (19.04 ± 1.02 %) than ultrasound pretreatment did (11.90 ± 0.53 %), whereas the proportion of peptides <10 kDa were higher in the second case (28.80 ± 0.07 vs. 20.46 ± 0.39 %). The fraction obtained by the ultrasound pretreatment containing peptides with a molecular weight between 1 and 10 kDa demonstrated the strongest ABTS radical scavenging efficacy among the fractions (97.54 ± 0.30) with IC₅₀ value of 4.31 mg/mL. Compared with single-enzyme processes, the two-stage enzymatic processes did not significantly improve both antioxidant and functional hydrolysates’ properties.     

Performance Improvement of DPSK Signal Reception Using Reconfigurable Multiple Bit Differential Detection in the Presence of Carrier Frequency Offset

In this paper we propose a reconfigurable multiple bit differential detection (MBDD) algorithm with diversity reception in the form of postdetection equal-gain combining (EGC) that can be used for the differential phase shift keying (DPSK) signal reception in the presence of significant frequency offsets. The proposed algorithm is based on the MBDD algorithm with the introduction of a mechanism for the estimation of the frequency offset. The algorithm is checking N _c frequency offsets around zero offset and chooses the one that is the most likely. The analysis shows that the receiver with the proposed algorithm provides signal reception with almost equal quality in a wide range of carrier frequency offsets around zero frequency offset.     

Internal oxidation of Ag–VC composites

The internal oxidation (IO) of Ag–VC composites containing 5 vol.% of carbide was examined at three oxidation temperatures (350, 400, 600 °C). Two mechanisms were observed due to the formation of double oxides with relatively low-melting points. At temperatures below the lowest eutectic point in situ, or diffusion less IO, was observed with the formation and growth of oxide layers surrounding the initial carbide. At temperatures above the eutectic point IO resulted in the formation of liquid oxide pools, which grew in size and developed into a network of oxides within the metal matrix. The kinetics confirmed the presence of two distinct mechanisms.     

Particle growth mechanisms in Ag-ZrO(2) and Au-ZrO(2) granular films obtained by pulsed laser deposition

Thin films consisting of Ag and Au nanoparticles embedded in amorphous ZrO(2) matrix were grown by pulsed laser deposition in a wide range of metal volume concentrations in the dielectric regime (0.08相似文献   

Cover Picture: Macromol. Mater. Eng. 9/2005

Summary: Inverse gas chromatography under finite surface coverage conditions (IGC‐FC) was used for the investigation of sorption of hexane, benzene, chloroform and tetrahydrofuran on macroporous crosslinked poly[(glycidyl methacrylate)‐co‐(ethylene glycol dimethacrylate)], poly(GMA‐co‐EGDMA), and copolymer modified with ethylene diamine, EDA, poly(GMA‐co‐EGDMA)‐en, in the temperature range 333–363 K. Two poly(GMA‐co‐EGDMA) samples with different porosity parameters were synthesized by suspension copolymerization and modified using a ring‐opening reaction of the pendant epoxy groups with EDA. The specific surface areas of the initial and modified copolymer samples were determined by the BET method from low temperature nitrogen adsorption isotherms (77 K). The adsorption isotherms determined from chromatographic peaks of adsorbates were analyzed using the BET theoretical model and used for estimation of the surface area, isosteric heat of adsorption and the adsorption energy distribution on the surface of the initial and modified copolymer samples. It was observed that the adsorbate nature and the properties of the solid surface of the initial and modified copolymer governed the uptake of adsorbate by the copolymer. The deviations observed for the S_a values obtained by the BET method from the low temperature nitrogen adsorption isotherms and hexane was attributed not only to the difference in molecule size, but also to the specific polymer‐adsorbate interactions. The isosteric heat of adsorption approached a constant value with increasing adsorbate loading. A large variation in the shapes of the q_st‐α curves resulted from strong acid‐base interactions, as well as dissolution phenomena. Of the four studied adsorbates, chloroform was shown to have the greatest affinity towards the surface of the investigated polymer samples.

Adsorption isotherms of hexane on sample 1 and 1a.