Properties of functions with monotone graphs

A metric space (X,d) is monotone if there is a linear order < on X and a constant c>0 such that d(x,y)≦cd(x,z) for all x<y<z∈X. Properties of continuous functions with monotone graph (considered as a planar set) are investigated. It is shown, for example, that such a function can be almost nowhere differentiable, but must be differentiable at a dense set, and that the Hausdorff dimension of the graph of such a function is 1.     

Mercury characterisation in urban particulate matter

A five-step sequential extraction procedure was proposed in order to assess the distribution of mercury (Hg) forms in urban particulate matter (PM): exchangeable, HCl-soluble, organic-bound, elemental and other slightly soluble Hg species, mercury(II) sulphide (HgS), and residual Hg. This process was applied to the analysis of urban dust samples collected at locations in Prague (Czech Republic) with high traffic density. In addition to sequential extractions, thermal desorption analysis was performed. The differences in Hg concentrations between untreated and thermally treated samples were indicated as the thermally releasable amount of Hg. For the study of PM-adsorbing capacity, Hg vapours were passed through the samples as long as the enrichment of materials was observed. The retained elemental Hg was readily released by thermal desorption. All Hg analyses were based on the highly sensitive pyrolysis technique of atomic absorption spectrometry using the mercury analyser AMA-254.     

Chiral memory and self-replication study of porphyrin and bilirubin aggregates formed on polypeptide matrices

Porphyrin heteroaggregates composed of meso-tetrakis(N-methylpyridinium-4-yl)porphinatocopper(II) and meso-tetrakis(4-sulfonatophenyl)porphyrin formed in the presence of a polyglutamic matrix possess chiral memory and an ability to self-replicate their supramolecular structures. By means of electronic circular dichroism spectroscopy, it has been shown that the self-replication process is not influenced by changes in pH or ionic strength. The average molecular weight of the polyglutamic matrix used for porphyrin aggregate preparation plays a crucial role with regard to the form of the resulting CD spectrum. In the second part of our study, a complex composed of polylysine and bilirubin as a model system for a structured homoaggregate formed on the chiral matrix has been tested for chiral memory phenomena. The results indicate that the bilirubin homoaggregate shows chiral memory.     

Synthesis of new (arylcarbonyloxy)aminopropanol derivatives and the determination of their physico-chemical properties

Eight hydrochlorides of 3-{2-[(2/4-fluorophenoxy)-ethylamino]}-2-hydroxypropyl-4-alkoxybenzoates and four hydrochlorides of 3-tert-butylamino-2-hydroxypropyl-4-butoxybenzoates were prepared as potential antagonists of the β₁-adrenergic receptor (beta-blockers). A multistep synthesis of these compounds is described as well as their detailed analytical characterization. The pharmacokinetic properties of these weak base compounds are significantly influenced by their acid-base dissociation constant, pK _a. The knowledge of this value is crucial for new drug development. This paper is aimed at developing a methodology that utilizes pH-dependent ¹H NMR spectroscopy for its routine analysis. The selected predicted physico-chemical parameters of the new (arylcarbonyloxy)aminopropanols (i.e., aryloxyaminopropanol derivatives) were compared with the model drugs esmolol and flestolol.      

Study of Microwave Torch Plasmachemical Synthesis of Iron Oxide Nanoparticles Focused on the Analysis of Phase Composition

This work presents the results obtained on the single-step route towards the synthesis of iron oxide nanoparticles in a microwave plasma torch. The torch is supplied by 660 sccm of Ar mixed with 1 sccm of Fe(CO)₅ and a variable amount of O₂. The influence of oxygen addition on the phase composition of the synthesized powder was studied. Magnetite and maghemite phases could not be distinguished using the standard X-ray diffraction (XRD) analysis. Therefore, a combined XRD and Raman spectra analysis had to be applied, which is based on fitting of selected diffraction peaks and spectral features. According to XRD and Raman spectroscopy, the powder synthesized from Ar/Fe(CO)₅ consisted about 50 % of magnetite, Fe₃O₄, the rest being α-Fe and FeO. An increase in oxygen flow rate led to an increase in γ-Fe₂O₃ percentage, at the expense of α-Fe, FeO and Fe₃O₄. Almost pure γ-Fe₂O₃ was synthesized at oxygen flow rates 25–75× higher than the flow rate of Fe(CO)₅. A further increase in the oxygen flow rate led to α-Fe₂O₃ and ε-Fe₂O₃ production. The distributions of nanoparticles’ (NPs) diameters were obtained using transmission electron microscopy (TEM) and dynamic light scattering (DLS). The mean diameter of the NPs measured by TEM was 13 nm while the DLS measurements led to the mean diameter of 12 nm. About 90 % of all particles had the diameter in the range of 5–21 nm but a few larger particles were observed in TEM micrographs.     

Assessment of waxy and non-waxy corn and wheat cultivars as starch substrates for ethanol fermentation

The amylose/amylopectin ratio in cereal substrates is one of the parameters affecting starch hydrolysis and fermentation process. Waxy (less than 1 mass % of amylose) starch seems to be suitable for improving the fuel ethanol production. The main aim of this paper was to characterize the fermentation performance of corn and wheat waxy and non-waxy cultivars in terms of simultaneous saccharification and fermentation (SSF) as well as of the separated hydrolysis and fermentation (SHF) type. Two corn (waxy and non-waxy) and two wheat (waxy and non-waxy) cultivars were used for the comparison applying separate enzymatic hydrolysis and fermentation. In the SHF process, the glucose content was higher after saccharification in the waxy corn and wheat compared to that in non-waxy corn and wheat. In the SSF of waxy varieties, the glucose content after the pre-saccharification was also higher than in the non-waxy ones. Although the starch content did not vary significantly, differences in the glucose content after saccharification were observed. The ethanol yield obtained after the distillation of mash varied from 229.2–262.3 L per ton for the SHF fermentation, while it was in the range of 311.5–347.9 L per ton for the SSF process.     

Examination of small molecule losses in 5‐methylpyranopelargonidin MS/MS CID spectra by DFT calculations

Pyranoanthocyanins are formed during food treatment and maturation (e.g. wine, juices), and they can be considered a natural alternative to artificial food colorants. Tandem mass spectrometry (MS/MS) is perhaps the most important technique in analysis of anthocyanin dyes. Knowledge of fragmentation pattern is a key aspect of their successful structural characterization. Polyphenolic compounds are known to lose small molecules during collision‐induced dissociation (CID) in MS/MS experiments. However, the specific positions where such losses occur preferentially are unknown. The aim of this communication is to investigate the energetically most preferred places for H₂O and CO losses during the fragmentation of 5‐methylpyranopelargonidin molecule by the means of computational chemistry (employing density functional theory) combined with CID MS/MS experiments and infrared multiphoton dissociation spectroscopy. Mechanisms responsible for the fragmentations were investigated, and optimal geometries and transition states were obtained. Cleavage of water as well as carbon monoxide occurs preferentially from the C‐ring of flavonoid skeleton. In the most stable structure of 5‐methylpyranopelargonidin, B‐ring was found to be tilted with respect to the rest of the molecule. Planarization effort of the parent molecule contributes both to its decarbonylation and dehydration. Copyright © 2014 John Wiley & Sons, Ltd.     

Strong measure zero in separable metric spaces and Polish groups

The notion of strong measure zero is studied in the context of Polish groups and general separable metric spaces. An extension of a theorem of Galvin, Mycielski and Solovay is given, whereas the theorem is shown to fail for the Baer–Specker group \({{\mathbb{Z}^{\omega}}}\). The uniformity number of the ideal of strong measure zero subsets of a separable metric space is examined, providing solutions to several problems of Miller and Steprāns (Ann Pure Appl Logic 140(1–3):52–59, 2006).