84 research outputs found

    Semiclassical Electron Correlation in Density-Matrix Time-Propagation

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    Lack of memory (locality in time) is a major limitation of almost all present time-dependent density functional approximations. By using semiclassical dynamics to compute correlation effects within a density-matrix functional approach, we incorporate memory, including initial-state dependence, as well as changing occupation numbers, and predict more observables in strong-field applications.Comment: 4.5 pages, 1 figur

    Parameters of Ensiled Maize With Biological and Chemical Additives

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    The amount of maize grown in Poland has increased rapidly. Nowadays it takes about 600,000 ha, 40% of which is used as silage. Changing climate in Poland, with dry summer followed by wet autumn with ground frost causes extensive moulds contamination and high presence of the fusarium toxins in the maize during the harvest. The norms accepted in the EU concerning the acceptable level of deoxynivalenol (DON) and zearalenol (ZON) in feedstuffs for cattle require detailed examination of this problem as it decides on the health quality and production results. The aim of the study was to evaluate the effects of ensiling forage maize with microbiological additive and chemical preservative on the DON and ZON amount. The effects of the secondary fermentation after the silos were open (stability evaluation) were also examined

    Parameters of Ensiled Maize With Biological and Chemical Additives

    Get PDF
    The amount of maize grown in Poland has increased rapidly. Nowadays it takes about 600,000 ha, 40% of which is used as silage. Changing climate in Poland, with dry summer followed by wet autumn with ground frost causes extensive moulds contamination and high presence of the fusarium toxins in the maize during the harvest. The norms accepted in the EU concerning the acceptable level of deoxynivalenol (DON) and zearalenol (ZON) in feedstuffs for cattle require detailed examination of this problem as it decides on the health quality and production results. The aim of the study was to evaluate the effects of ensiling forage maize with microbiological additive and chemical preservative on the DON and ZON amount. The effects of the secondary fermentation after the silos were open (stability evaluation) were also examined

    Hygienic Value and Mycotoxins Level of Grass Silage in Bales for Horses

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    Mycotoxins are secondary metabolites of moulds which have adverse effects on humans, animals, and crops and result in illnesses and economic losses. The toxins may occur in storage under conditions favourable for the growth of the toxin-producing fungus or fungi. The highest forage concentration of toxins was found in horizontal storage methods such as bunker silos and feed piles, which were left open to oxygen. In any fermentation storage system, temperature and the presence of moisture is sufficient for toxin production. In a plastic covered storage system, oxygen penetration is slowed but not eliminated. The longer silage is stored, the greater the opportunity for significant fungus growth and toxin contamination. Although the effects of mycotoxins on horses are not well documented in scientific literature, in many situations mycotoxin problems appear to be significant e.g. colic, neurological disorders, paralysis and brain lesions. The aim of this study was to determine the level of mycotoxins in grass silage prepared in bales for horses

    Structures in multicomponent polymer films : their formation, observation, applications in electronics and biotechnology

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    Several strategies to form multicomponent films of functional polymers, with micron, submicron and nanometer structures, intended for plastic electronics and biotechnology are presented. These approaches are based on film deposition from polymer solution onto a rotating substrate (spin-casting), a method implemented already on manufacturing lines. Film structures are determined with compositional (nanometer) depth profiling and (submicron) imaging modes of dynamic secondary ion mass spectrometry, near-field scanning optical microscopy (with submicron resolution) and scanning probe microscopy (revealing nanometer features). Self-organization of spin-cast polymer mixtures is discussed in detail, since it offers a one-step process to deposit and align simultaneously domains, rich in different polymers, forming various device elements: (i) Surface segregation drives self-stratification of nanometer lamellae for solar cells and anisotropic conductors. (ii) Cohesion energy density controls morphological transition from lamellar (optimal for encapsulated transistors) to lateral structures (suggested for light emitting diodes with variable color). (iii) Selective adhesion to substrate microtemplates, patterned chemically, orders lateral structures for plastic circuitries. (iv) Submicron imprints of water droplets (breath figures) decorate selectively micron-sized domains, and can be used in devices with hierarchic structure. In addition, selective protein adsorption to regular polymer micropatterns, formed with soft lithography after spin-casting, suggests applications in protein chip technology. An approach to reduce lateral blend film structures to submicron scale is also presented, based on (annealed) films of multicomponent nanoparticles

    OmpR controls Yersinia enterocolitica motility by positive regulation of flhDC expression

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    Flagella and invasin play important roles during the early stages of infection by the enteric pathogen Yersinia enterocolitica. Our previous study demonstrated that OmpR negatively regulates invasin gene expression at the transcriptional level. The present study focused on the role of OmpR in the regulation of flagella expression. Motility assays and microscopic observations revealed that an ompR mutant strain exhibits a non-motile phenotype due to the lack of flagella. An analysis of flhDC::lacZYA chromosomal fusions demonstrated a decrease in flhDC expression in ompR mutant cells, suggesting a role for OmpR in the positive control of flagellar master operon flhDC, which is in contrast to the negative role it plays in Escherichia coli. Moreover, high temperature or osmolarity and low pH decreased flhDC expression and OmpR was not required for the response to these factors. Evidence from an examination of the DNA binding properties of OmpR in vitro indicated that the mechanism by which OmpR regulates flhDC is direct. Electrophoretic mobility shift assays confirmed that OmpR binds specifically to the flhDC promoter region and suggested the presence of more than one OmpR-binding site. In addition, phosphorylation of OmpR by acetyl-P appeared to stimulate the binding abilities of OmpR. Together with the results of our previous studies revealing the negative role of OmpR in the regulation of invasin expression, these findings support a model in which invasion and motility might be reciprocally regulated by OmpR

    Analysis of techniques used in bread dough dividing and forming

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    W pracy przedstawiono produkcję pieczywa metodą ręczną, mechaniczną i mieszaną, zwracając uwagę na etapy dzielenia i formowania ciasta. W celu porównania właściwości ciasta i wypieczonych bochenków poddano je ocenie organoleptycznej i badaniom fizykochemicznym (pomiary kwasowości i temperatury ciasta, oraz pomiary objętości, wilgotności i kwasowości miareczkowej gotowego wyrobu).Manual, mechanical, and mixed methods of bread production with attention focused on steps of dividing and forming dough are presented in the paper. In order to compare properties of dough and baked loaves, they underwent organoleptic and physicochemical tests. Physieochemical tests comprised: measurements of acidity and temperature of dough, measurements of volume, humidity and titration acidity of baked bread

    Modified atmosphere packaging and quality organic bread spell ed

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    W artykule omówiono wpływ pakowania w MAP (pakowanie w modyfikowanej atmosferze) na jakość ekologicznego pieczywa orkiszowego (Triticum spelta L.). Pieczywo zapakowano w dwóch różnych mieszankach gazowych w opakowania w formie woreczków barierowych i przechowywano w temperaturze pokojowej przez okres około miesiąca. Badane pieczywo poddano ocenie sensorycznej, fizykochemicznej i punktowej.The article presents impact of modified atmosphere packaging (MAP) on the quality of organic spelled (Triticum spelta L.) bread. Bread packed in two different gas mixtures in the form of packaging barrier bags and stored at room temperature for about a month. Test breads were subjected to sensory examination, physicalchemistry and score evaluation
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