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31.
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   
32.
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   
33.
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   
34.
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   
35.
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   
36.
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   
37.
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   
38.
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   
39.
The polyacrylate anion exchangers are widely used in purification of heavy metal ions from wastewaters and different accompanying complexing agents. Such effluents containing the chelators (EDTA, NTA, HEDTA, DTPA, and IDA) are discharged from relevant industries such as printed circuits boards, plating on plastics, metal finishing and others. The sorption was studied as a function of phase contact time and pH by the batch technique. It was found that the removal of heavy metal ions in the presence of EDTA, NTA and IDA strictly depends on the phase contact time and pH values. Various kinetic models such as the pseudo first-order and the pseudo second-order as well as the intraparticle one were also tested to estimate the sorption rate. The equilibrium capacities of the studied anion exchangers for Cu(II), Zn(II), Co(II), Ni(II), Pb(II) and Cd(II) in the presence of EDTA were the highest for Pb(II) and Cd(II). The order of sorption for Amberlite IRA 458, Amberlite IRA 958 as well as Amberlite IRA 67 can be as follows: Pb(II) > Cd(II) > Zn(II) > Cu(II) > Ni(II) > Co(II). The stability of forming complexes was also compared. The estimation of the capacities of anion exchangers under investigation by the continuous column studies was also carried out.  相似文献   
40.
We describe the major features of the completely decentralized adaptive file system MELODY which was designed for realizing anintegrated system design for a distributed real-time system working in a hazardous and unpredictable environment. MELODY's adaptivity mechanisms are based on novel services rendered by the distributed operating system DRAGON SLAYER. The file system, in order to both meet real-time constraints and provide for high availability, allows for replicating, relocating, or deleting file copies. Such copies may also bepublic orprivate. At every site aLocal Task Scheduler tries to schedule the arriving critical tasks, based on the availability of resources at this site such that deadline failures are minimized. Depending on the deadline failure history, status changes as well as file replication, deletion, or relocation are analyzed and managed by the cooperatingLocal File Assigners. In order to analyze MELODY's real-time performance we report on simulation experiments in which its capability of minimizing deadline failures of time-critical tasks was compared to other file system models: an idealbest-case model, abaseline model with no file replication, a file system allowingonly for replication ofprivate copies, and a model which allows forreplication and relocation of public copies only. While the best-case is unrealistic for a distributed implementation, the other models embody only part of MELODY's mechanisms yet have the benefit of a considerably smaller communication overhead. We report on the distributed simulation results which unambiguously show MELODY's superior performance, in addition to the built-in sensitivity to changes in the environment. A DRAGON SLAYER/MELODY prototype has been completed in our labs in order to serve as a distributed real-time testbed in our future work with MELODY.This work was partially supported by IBM Endicott (research Agreement No. 6073-86) by the State of Michigan (IMR-87-146751), and by General Dynamics Land Systems (#DEY-605089).  相似文献   
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