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31.
Dorota Neugebauer Paulina Maksym‐Bębenek Anna Mielańczyk Tadeusz Biela 《Polymer Engineering and Science》2013,53(6):1146-1153
The reactive oxirane groups were incorporated into the macromolecule as substituents in the side chains of loosely‐grafted copolymer or in the arms of star‐shaped copolymer using glycidyl methacrylate (GMA) in the controlled atom transfer radical polymerization (ATRP). The branched GMA copolymers with various architectures were obtained by using hydrophobic copolymers containing six and seven units of caprolactone 2‐(methacryloyloxy)ethyl ester (CLMA) functionalized with bromoester groups, and trifunctional poly(ε‐caprolactone) (PCL), as well as hydrophilic tri‐, and six‐functional acetal derivatives of D ‐glucopyranosides as (macro)initiators with biodegradable and biocompatible properties. The well‐defined copolymers with core‐shell structures and polymerization degrees of GMA in the range of 20–100 per side chain/arm at 20–70% of monomer conversion within 1–6 h and narrow molecular weight distributions (Mw/Mn = 1.14–1.4) were obtained. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers 相似文献
32.
Magdalena Luczak Joanna Suszynska-Zajczyk Lukasz Marczak Dorota Formanowicz Elzbieta Pawliczak Maria Wanic-Kossowska Maciej Stobiecki 《International journal of molecular sciences》2016,17(5)
The major cause of mortality in patients with chronic kidney disease (CKD) is atherosclerosis related to traditional and non-traditional risk factors. However, the understanding of the molecular specificity that distinguishes the risk factors for classical cardiovascular disease (CVD) and CKD-related atherosclerosis (CKD-A) is far from complete. In this study we investigated the disease-related differences in the proteomes of patients with atherosclerosis related and non-related to CKD. Plasma collected from patients in various stages of CKD, CVD patients without symptoms of kidney dysfunction, and healthy volunteers (HVs), were analyzed by a coupled label-free and mass spectrometry approach. Dysregulated proteins were confirmed by an enzyme-linked immunosorbent assay (ELISA). All proteomic data were correlated with kidney disease development and were subjected to bioinformatics analysis. One hundred sixty-two differentially expressed proteins were identified. By directly comparing the plasma proteomes from HVs, CKD, and CVD patients in one study, we demonstrated that proteins involved in inflammation, blood coagulation, oxidative stress, vascular damage, and calcification process exhibited greater alterations in patients with atherosclerosis related with CKD. These data indicate that the above nontraditional risk factors are strongly specific for CKD-A and appear to be less essential for the development of “classical” CVD. 相似文献
33.
Magdalena Zielińska-Dawidziak Dorota Piasecka-Kwiatkowska Jerzy R. Warchalewski Agnieszka Makowska Magdalena Gawlak Jan Nawrot 《European Food Research and Technology》2014,238(5):829-835
Grains of winter wheat (Korweta variety) were partially germinated in an abiotic stress condition (0–15 mM FeSO4 solutions) in order to accumulate iron by ferritin overexpression. The physical, chemical, biochemical properties and technological parameters of the obtained material as well as their resistance to an insect storage pest—granary weevil—were analyzed. Sprouted wheat grains with overexpression of ferritin contain 52 times more iron, more than 50 % in form of ferritin. The contents of reducing sugars, crude protein, fiber and ash as well as amylolytic activity increased significantly in sprouted wheat grain, while starch, fat, wet gluten, falling number and inhibition activity against granary weevil α-amylase decreased. Germinated wheat grain enriched with iron strongly affected granary weevil developmental parameters. Despite the fact that technological parameters of the product were deteriorated, it is worth to consider this material application as an iron supplement for cereal products, when the application of soybean is impossible. 相似文献
34.
Dorota Rutkowska-Zbik Agnieszka Drzewiecka-Matuszek Malgorzata Witko 《Topics in Catalysis》2014,57(10-13):946-952
The present brief review aims at elucidation of the parameters affecting the properties and reactivity of high valent iron(IV) oxo porphyrin complexes, being models of compound II reactive intermediate known from biochemistry of cytochromes and peroxidases. The stress is put on the influence of the axial ligand and porphyrin ring substituents, with special attention on implications for their catalytic activity. 相似文献
35.
Grażyna Budryn Dorota Żyżelewicz Ewa Nebesny Joanna Oracz Wiesława Krysiak 《Food research international (Ottawa, Ont.)》2013,50(1):149-160
This study investigated the influence of antioxidants of green tea aqueous extract (GTE) and green coffee aqueous extract (GCE) in concentrations of 0.25, 0.5 and 1 g·100 g? 1 on the nutritional properties of fine yeast pastry fried products such as donuts. Yeast donuts were made according to the traditional processing technology. In fried donuts physical properties (water activity, pH, hardness and color with the use of instrumental methods) as well as sensory properties were established. Moreover, quality of fat extracted from donuts (composition of fatty acids and peroxide value), content of acrylamide, composition of polyphenols and antioxidant activity were analyzed. Obtained extracts of GTE and GCE contained 26 and 41% of polyphenols, respectively, and the degree of polyphenol degradation during production of donuts was less when the dilution in dough was greater. Both tests indicated that the highest antioxidant activity had donuts with the highest analyzed addition of extract, however depending on the applied test or GTE or GCE had better antioxidant properties. Fatty acid composition was the most beneficial when the addition of GTE and GCE was on a level of 0.25 and 0.5 g·100 g? 1, respectively. In fried donuts relatively low amounts of acrylamide were obtained, amounting to 18–46 μg·kg? 1. Only the lowest addition of GTE and the highest addition of GCE caused an increase of acrylamide content in donuts, while all other levels of added extracts caused a decrease in the content of formed acrylamide. 相似文献
36.
Mackiewicz P Kowalczuk M Mackiewicz D Nowicka A Dudkiewicz M Laszkiewicz A Dudek MR Cebrat S 《Yeast (Chichester, England)》2002,19(7):619-629
We have compared the results of estimations of the total number of protein-coding genes in the Saccharomyces cerevisiae genome, which have been obtained by many laboratories since the yeast genome sequence was published in 1996. We propose that there are 5300-5400 genes in the genome. This makes the first estimation of the number of intronless ORFs longer than 100 codons, based on the features of the set of genes with phenotypes known in 1997 to be correct. This estimation assumed that the set of the first 2300 genes with known phenotypes was representative for the whole set of protein-coding genes in the genome. The same method used in this paper for the approximation of the total number of protein-coding sequences among more than 40 000 ORFs longer than 20 codons gives a result that is only slightly higher. This suggests that there are still some non-coding ORFs in the databases and a few dozen small ORFs, not yet annotated, which probably code for proteins. 相似文献
37.
Majczak A Karbowski M Kamiński M Masaoka M Kurono C Niemczyk E Kedzior J Soji T Knap D Hallmann A Wakabayashi T 《Journal of electron microscopy》2004,53(6):635-647
Effects of jasplakinolide (JSP), a stabilizer of F-actin, and latrunculin A (LTA), a destabilizer of F-actin, on a series of events occurring in the execution phase of staurosporine (STS)-induced apoptotic processes were studied using human osteosarcoma 143B cells. Time-dependent apparent increases of the population of cells with collapsed membrane potential of mitochondria (Delta Psi(m)) caused by STS treatment were not due to actual decreases in the Delta Psi(m) per cell, but due to the fragmentation of cells resulting in decreases in the number of active mitochondria per cell. Decreases in the Delta Psi(m) in fragmented cells occurred late in the execution phase. Both JSP and LAT failed to prevent STS-induced release of cytochrome c from mitochondria followed by the activation of caspases 3 and 9, the cleavage of poly (ADP-ribose) polymerase (PARP) and apoptotic nuclear fragmentation. However, both drugs prevented STS-induced apoptotic cell fragmentation and decreases in the Delta Psi(m). These results indicate that physicochemical states of actin filaments play a certain role in the execution phase of STS-induced apoptotic processes. 相似文献
38.
Mechanical flexing of plastic substrates coated with thin film permeation barriers causes stress-induced cracks that may lead to device degradation. This phenomenon is of particular importance for organic light emitting diodes, an emerging display technology that can be implemented on flexible substrates but imposes stringent requirements on the barrier performance. We demonstrate a dry-etch-based method to highlight cracks in thin films of transparent materials and make them visible under a conventional optical microscope on samples in a neutral, relaxed position. This approach allows for rapid evaluation of the mechanical performance of thin film barriers on flexible substrates. 相似文献
39.
Dorota Głowacz‐Czerwonka 《应用聚合物科学杂志》2013,128(5):3465-3472
This work presents conditions and method for obtaining foamed melamine–formaldehyde–butanone (Mel‐F‐MEK) materials of improved thermal stability. They were obtained from melamine solution in reactive solvents based on ethyl methyl ketone and 4,4′‐diphenylmethane diisocyanate. Some properties of obtained polyurethane foams were examined, e.g., apparent density, water absorption, dimensional stability, thermal conductivity, flammability, as well as static and dynamic thermal stability and compressive strength. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
40.
Dorota A. Chwieduk 《Renewable Energy》2009,34(3):736-741
It is important to know how to design a building to meet seasonally varying energy needs. In high latitude countries in winter the demand for space heating is high and a building envelope should receive maximum incident solar energy. On the other hand, in summer, walls and roofs exposed to incident solar radiation usually require shading to avoid too much solar gain. Data on solar energy availability are crucial for good building design. However, it is important how the availability of solar radiation is determined. An important aim of the paper presented is to give some results of a comparative analysis of two basic sky models, isotropic: Hottel–Woertz–Liu–Jordan and anisotropic: the HDKR, Hay–Davies–Klucher–Reindl, to recommend one of these models for determination of solar energy availability on a building envelope and to formulate the energy balance of a building. Differences between results obtained from both models increase with the slope of exposed surfaces. The biggest differences (12–15%) are evident for vertical south surfaces, especially in summer. The simplified isotropic sky model is not recommended for evaluation of solar radiation availability on the building envelope. Underestimation of solar gains can lead to the selection of an unsuitable concept and construction of a building and result in poor indoor thermal comfort, i.e. overheating of rooms in summer. 相似文献