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21.
Beata Podkościelna 《应用聚合物科学杂志》2011,120(5):3020-3026
Synthesis, copolymerization, and physicochemical properties of new, of different degrees of crosslinker tetrafunctional bis[4(2‐hydroxy‐3‐methacryloyloxypropoxy)phenyl]sulfide and glycidyl methacrylate copolymers are presented. The monomers were used for the synthesis of porous microspheres in the presence of pore‐forming diluents, decan‐1‐ol, and toluene. Influence of diluents composition on their porous structures was studied. Porous structure of the obtained microspheres in dry (from nitrogen adsorption–desorption measurements) states was studied. Their chemical structures were studied by the use of Fourier transform infrared. The number of epoxy groups of the obtained copolymers, their thermal properties (thermogravimetric analysis), and swelling characteristics in 10 solvents of different chemical nature were examined. Selected copolymers were modified by amines in the epoxide ring‐opening reaction. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
22.
Lara Valentín Beata Kluczek‐Turpeinen Pekka Oivanen Annele Hatakka Kari Steffen Marja Tuomela 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(6):851-858
BACKGROUND: For most dioxin‐contaminated sawmill soils, combustion is recommended. However, the process may be inefficient if the soil has a high organic matter content. The use of saprotrophic basidiomycetous fungi is an alternative for pretreatment of this kind of soil. A total of 147 fungi were evaluated for their ability to grow in sawmill soil. From this screening, the best soil colonizing fungi were selected to study their enzyme activities and degradation of soil organic matter. Pine (Pinus sylvestris) bark was used as a co‐substrate to propagate the fungi into the soil. The activities of manganese peroxidase (MnP), laccase, endo‐1,4‐β‐glucanase, endo‐1,4‐β‐xylanase, and endo‐1,4‐β‐mannanase were analysed from the inocula and fungal treated soil. RESULTS: The screening revealed that 56 out of 147 fungi were able to grow in non‐sterile soil, and most of them were litter‐decomposing fungi (LDF). In pine bark cultures, the highest enzyme activities were observed with Phanerochaete velutina, which produced 5 U g?1 of MnP. The activity of endo‐1,4‐β‐glucanase was generally higher than that of other hydrolytic enzymes. The highest carbon loss from soil with a high organic matter content was achieved by P. velutina (3.4%) and Stropharia rugosoannulata (2.4%). CONCLUSIONS: Many LDF, and in addition the white‐rot fungus P. velutina, are potential degraders of soil organic matter since they showed good growth and respiratory activity. Pine bark was a suitable lignocellulosic co‐substrate and a good promoter of MnP activity. Copyright © 2009 Society of Chemical Industry 相似文献
23.
Aneta Stachowicz Anna Winiewska Katarzyna Ku Magdalena Biaas Magdalena omnicka Justyna Toto-uraska Anna Kiepura Kamila Stachyra Maciej Suski Beata Bujak-Giycka Jacek Jawie Rafa Olszanecki 《International journal of molecular sciences》2021,22(11)
Atherosclerosis and nonalcoholic fatty liver disease are leading causes of morbidity and mortality in the Western countries. The renin–angiotensin system (RAS) with its two main opposing effectors, i.e., angiotensin II (Ang II) and Ang-(1–7), is widely recognized as a major regulator of cardiovascular function and body metabolic processes. Angiotensin-converting enzyme 2 (ACE2) by breaking-down Ang II forms Ang-(1–7) and thus favors Ang-(1–7) actions. Therefore, the aim of our study was to comprehensively evaluate the influence of prolonged treatment with ACE2 activator, diminazene aceturate (DIZE) on the development of atherosclerotic lesions and hepatic steatosis in apoE−/− mice fed a high-fat diet (HFD). We have shown that DIZE stabilized atherosclerotic lesions and attenuated hepatic steatosis in apoE−/− mice fed an HFD. Such effects were associated with decreased total macrophages content and increased α-smooth muscle actin levels in atherosclerotic plaques. Moreover, DIZE changed polarization of macrophages towards increased amount of anti-inflammatory M2 macrophages in the atherosclerotic lesions. Interestingly, the anti-steatotic action of DIZE in the liver was related to the elevated levels of HDL in the plasma, decreased levels of triglycerides, and increased biosynthesis and concentration of taurine in the liver of apoE−/− mice. However, exact molecular mechanisms of both anti-atherosclerotic and anti-steatotic actions of DIZE require further investigations. 相似文献
24.
Rogman Agnieszka Gancarz Roman Domagalska Beata W. Wilk Kazimiera A. 《Topics in Catalysis》2000,11(1-4):451-460
In this work we present mechanism of the base-catalyzed 2-azaallylic rearrangement in homogeneous media. Detailed 2-azaallylic
rearrangement studies have shown that tautomerism of derivatives of benzylidenebenzhydrylamines and N-fluorenylidenebenzylamines
is not adequately encomposed by the Hammet equation and the equilibrium constant in the case of studied derivatives depends
on the electronic as well as steric factors of the azaallylic system substituents. The presence of steric interactions which
influence the equilibrium state has been additionally confirmed by means of crystallographic and molecular mechanics data
as well as NOE studies.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
25.
Beata Olejnik Anna Jarz?b Ewa M. Kratz Mariusz Zimmer Andrzej Gamian Miros?awa Ferens-Sieczkowska 《International journal of molecular sciences》2015,16(7):14933-14950
The impact of seminal plasma components on the fertilization outcomes in humans is still under question. The increasing number of couples facing problems with conception raises the need for predictive biomarkers. Detailed understanding of the molecular mechanisms accompanying fertilization remains another challenge. Carbohydrate–protein recognition may be of key importance in this complex field. In this study, we analyzed the unique glycosylation pattern of seminal plasma proteins, the display of high-mannose and hybrid-type oligosaccharides, by means of their reactivity with mannose-specific Galanthus nivalis lectin. Normozoospermic infertile subjects presented decreased amounts of lectin-reactive glycoepitopes compared to fertile donors and infertile patients with abnormal semen parameters. Glycoproteins containing unveiled mannose were isolated in affinity chromatography, and 17 glycoproteins were identified in liquid chromatography-tandem mass spectrometry with electrospray ionization. The N-glycome of the isolated glycoproteins was examined in matrix-assisted laser desorption ionization mass spectrometry. Eleven out of 27 identified oligosaccharides expressed terminal mannose residues, responsible for lectin binding. We suggest that lowered content of high-mannose and hybrid type glycans in normozoospermic infertile patients may be associated with impaired sperm protection from preterm capacitation and should be considered in the search for new infertility markers. 相似文献
26.
27.
Janina Kabatc Edyta Krzyżanowska Beata Jędrzejewska Marek Pietrzak Jerzy Pączkowski 《应用聚合物科学杂志》2010,118(1):165-172
Results of kinetic studies of two‐component photoinitiator systems used in the visible‐light photoinduced polymerization of 2‐ethyl‐2‐(hydroxymethyl)‐1,3‐propanediol triacrylate are presented. Nine different styrylquinolinum dyes coupled with n‐butyltriphenylborate as a coinitiator have been used as photoinitiating systems. Reactive radicals that initiate the polymerization are formed by the well‐known mechanism of photoinduced electron transfer between dye cations acting as electron acceptors and borate anions acting as electron donors. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
28.
Plants infested with herbivores release specific volatile compounds that are known to recruit natural enemies. The response
of natural enemies to these volatiles may be either learned or genetically determined. We asked whether there is genetic variation
in the response of the predatory mite Phytoseiulus persimilis to methyl salicylate (MeSa). MeSa is a volatile compound consistently produced by plants being attacked by the two-spotted
spider mite, the prey of P. persimilis. We predicted that predators express genetically determined responses during long-distance migration where previously learned
associations may have less value. Additionally, we asked whether these responses depend on odors from uninfested plants as
a background to MeSa. To infer a genetic basis, we analyzed the variation in response to MeSa among iso-female lines of P. persimilis by using choice-tests that involved either (1) MeSa presented as a single compound or (2) MeSa with background-odor from
uninfested lima bean plants. These tests were conducted for starved and satiated predators, i.e., two physiological states,
one that approximates migration and another that mimics local patch exploration. We found variation among iso-female lines
in the responses to MeSa, thus showing genetic variation for this behavior. The variation was more pronounced in the starved
predators, thus indicating that P. persimilis relies on innate preferences when migrating. Background volatiles of uninfested plants changed the predators’ responses to
MeSa in a manner that depended on physiological state and iso-female line. Thus, it is possible to select for context-dependent
behavioral responses of natural enemies to plant volatiles. 相似文献
29.
Beata Zielińska Ewa Borowiak-PalenBarbara Grzmil Ryszard J. Kalenczuk 《Journal of Alloys and Compounds》2011,509(17):5414-5419
Titanate nanorods with high photocatalytic activity was successfully synthesized through a simple catalyst-free hydrothermal method. The photocatalytic degradation of a model organic dye (Reactive Red 198) was accelerated by the calcination of the nanorods prior the reaction. The calcination of nanorods did not modify their morphology, however the crystallinity of the samples was significantly improved. Therefore, the quality of the samples is a key parameter determining their activity in the investigated photocatalytic process. The as-produced and annealed catalysts were characterized by high-resolution transmission electron microscopy (HR-TEM), X-ray diffraction (XRD), Diffuse Reflectance (DR) UV-Vis and resonance Raman spectroscopy. 相似文献
30.
Beata Klamczynska Zuzanna Czuchajowska & Byung-Kee Baik 《International Journal of Food Science & Technology》2001,36(5):563-572
We investigated both the distribution of protein, ash and starch in legume (chickpeas, smooth and wrinkled peas) cotyledons, and the soaking and cooking characteristics, including gelatinization and retrogradation, of the starch. There were large differences in composition between different types of legumes and also between the outer and inner parts of legume cotyledons. Wrinkled peas exhibited much higher water absorption during prolonged soaking and there were higher hardness value determined for cooked seeds compared with chickpeas and smooth peas. While the hardness of cooked seeds decreased continuously as cooking time increased to 110 min, all legume starch was fully gelatinized after cooking for 70 min. 相似文献