States on sharply dominating effect algebras

We prove that sharply dominating Archimedean atomic lattice effect algebras can be characterized by the property called basic decomposition of elements.As an application we prove the state smearing theorem for these effect algebras.     

Analysis of multiple mycotoxins in beer employing (ultra)-high-resolution mass spectrometry

The objective of the presented study was to develop and optimize a simple, high-throughput method for the control of 32 mycotoxins (Fusarium and Alternaria toxins, aflatoxins, ergot alkaloids, ochratoxins, and sterigmatocystin) in beer. Due to the broad range of their physicochemical properties, the sample preparation step was simplified as much as possible to avoid analyte losses. The addition of acetonitrile to beer samples enabled precipitation of abundant matrix components. The clean-up efficiency was controlled by ambient mass spectrometry employing a direct analysis in real time (DART) ion source. For determination of analytes, ultra-high-performance liquid chromatography hyphenated with high-resolution mass spectrometry utilizing an orbitrap (U-HPLC-orbitrapMS) or time-of-flight (TOFMS) technology was used. Because of significantly better detection capabilities of the orbitrap technology, the U-HPLC-orbitrapMS method was chosen as a determinative step and fully validated. To compensate matrix effects, matrix-matched calibration was employed. The lowest calibration levels for most of the target mycotoxins ranged from 1 to 8 μg L(-1) beer and the recoveries of analytes were in range from 86 to 124%.     

Subalgebras, Intervals, and Central Elements of Generalized Effect Algebras

The relation between generalized effect algebrasand D-algebras and their subalgebras are discussed. Forgeneralized effect algebras the notion of centralelements is introduced and some of their properties are shown.     

Zur Kenntnis einiger Triazole und ihrer Abkömmlinge

Ohne Zusammenfassung     

Properties of Quasi-Hermitian Operators Inherited from Self-Adjoint Operators

We study a generalized effect algebra of unbounded linear operators in an infinite-dimensional complex Hilbert space. This algebra equipped with a certain kind of topology allows us to show that unbounded quasi-Hermitian operators can be expressed as a difference of two infinite sums of bounded quasi-Hermitian operators.     

Design and economics of industrial production of fructooligosaccharides

A process for industrial production of fructooligosaccharides (FOS’s) based on the conversion of sucrose by immobilized fructosyltransferase (FTase) from the cells of Aureobasidium pullulans CCY 27-1-94 was developed. Particular process operations and conditions were designed employing results of laboratory and semi-pilot scale experiments. The process flowsheet comprised three sections: FTase production, which included fermentation, isolation and purification of the enzyme, FTase immobilization and FOS’s production where a product with a high content of FOS’s was prepared by the removal of glucose, fructose and unreacted sucrose from the reaction mixture using simulated moving-bed chromatography. Two alternative process flowsheets were proposed for the annual production of 10 000 t of FOS’s: one for a powdery product and the second one for syrup. The economic analysis provided the costs for the production of immobilized FTase and FOS’s using two different price estimates for sucrose.     

Analytical artefacts in the speciation of arsenic in clinical samples

Urine and blood samples of cancer patients, treated with high doses of arsenic trioxide were analysed for arsenic species using HPLC-HGAFS and, in some cases, HPLC-ICPMS. Total arsenic was determined with either flow injection-HGAFS in urine or radiochemical neutron activation analysis in blood fractions (in serum/plasma, blood cells). The total arsenic concentrations (during prolonged, daily/weekly arsenic trioxide therapy) were in the μg mL⁻¹ range for urine and in the ng g⁻¹ range for blood fractions. The main arsenic species found in urine were As(III), MA and DMA and in blood As(V), MA and DMA.With proper sample preparation and storage of urine (no preservation agents/storage in liquid nitrogen) no analytical artefacts were observed and absence of significant amounts of alleged trivalent metabolites was proven. On the contrary, in blood samples a certain amount of arsenic can get lost in the speciation procedure what was especially noticeable for the blood cells although also plasma/serum gave rise to some disappearance of arsenic. The latter losses may be attributed to precipitation of As(III)-containing proteins/peptides during the methanol/water extraction procedure whereas the former losses were due to loss of specific As(III)-complexing proteins/peptides (e.g. cysteine, metallothionein, reduced GSH, ferritin) on the column (Hamilton PRP-X100) during the separation procedure. Contemporary analytical protocols are not able to completely avoid artefacts due to losses from the sampling to the detection stage so that it is recommended to be careful with the explanation of results, particularly regarding metabolic and pharmacokinetic interpretations, and always aim to compare the sum of species with the total arsenic concentration determined independently.     

A study of the effects of column porosity on gradient separations of proteins

The type of the stationary phase for reversed-phase liquid chromatography significantly affects the sample elution. Hydrodynamic properties, efficiency and gradient elution of proteins were investigated on five commercial C18 columns with wide-pore totally porous particles, with superficially porous layer particles, non-porous particles and a silica-based monolithic bed. The efficiency in the terms of reduced plate height is higher for low-molecular ethylbenzene than for proteins, but depends on the character of the pores in the individual columns tested. The superficially porous Poroshell and the non-porous Micra columns provide the best efficiency for proteins at high mobile phase flow rates, probably because of similar pore architecture in the stationary phase. The Zorbax column with similar pore architecture as the Poroshell active layer, i.e. narrow pore distribution of wider pores shows better efficiency than the packed column with narrow pores and broad pore distribution. The monolithic column shows lower efficiency for proteins at high flow rates, but it performs better than the broad-pore distribution totally porous particulate columns. Different pore architecture affects also the retention and selectivity for proteins on the individual columns. The retention times on all columns can be predicted using the model for reversed-phase gradient elution developed originally for low-molecular compounds. Consideration of the limited pore volume accessible to the biopolymers has negligible effect on the prediction of retention on the columns packed with non-porous or superficially porous particles, but improves the accuracy of the predicted data for the totally porous columns with broad pore distribution.     

Magnetic Bead Cellulose as a Suitable Support for Immobilization of α-Chymotrypsin

Magnetic bead cellulose was prepared by a suspension method from the mixture of viscose and magnetite using thermal sol?Cgel transition and regeneration of cellulose. The prepared magnetic particles after their activation with divinyl sulfone were shown to be suitable magnetic carrier for immobilization of ??-chymotrypsin and for its application in proteomic studies. The specific activity of the immobilized proteinase was high; its activity did not change in the course of storage. The following properties of the immobilized proteinase were compared with those of the soluble enzyme: pH and temperature dependence of the activity, self-cleavage activity, and possibility of repeated use. ??-Chymotrypsin immobilized to magnetic bead cellulose was used for the proteolytic digestion of porcine pepsin A and human gastric juice and a possibility of direct use of enzyme reaction products for matrix-assisted laser desorption/ionization time of flight mass spectrometry analysis was shown.