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The present work considers Strouma River on the Bulgarian territory using the integral method for evaluation of climatic and anthropogenic impacts on the average annual water volume and maximum and minimum water flow. The level of this impact and risk assessment is determined by the index Mmax, i for the deviation of the maximum water flow from the maximum flow norm Qmax, 0 and the index Mmin, i for the deviation of the minimum water flow from the minimum flow norm Qmin, 0. Using the dynamics of the integral indices Mmax, i, Mmin, i and information on extreme events from the past, a preliminary risk assessment of future extreme events such as floods and draughts could be made. This is done for the first time in risk assessment of extreme events and has been checked at Pernik (in the beginning) and Marino pole (at the border in Greece) for the period 1948 - 2006.

The liquid extraction of the 13 lanthanides with mixtures of 8-hydro­xyquinoline (HQ) and crown ethers (S) dibenzo-18-crown-6 (DB18C6) and di­benzo-24-crown-8 (DB24C8) in 1,2-dichloroethane as a diluent from chloride medium at constant ionic strength µ = 0.1 was investigated. The composition of the extracted species was established as LnQ3 with HQ alone and as LnQ3·S in the presence of a crown ether. The values of the equilibrium constants were calculated. The addition of DB18C6 to the metal chelate system improved the extraction efficiency, while a weak synergistic enhancement was found when the metals were extracted with mixtures of HQ-DB24C8. The parameters of the extraction process were determined and the separation factors between two adjacent lanthanides(III) were calculated.

Hexamethylenetetramine (urotropine) is a compound that is often used in foot care products. Urotropine (hexamethylenetetramine) has a broad antibacterial effect (due to release of formaldehyde), which ensures the elimination of already occurring microorganisms and prevent the recurrence of infections, so commonly is used in cosmetic products for skin care of the feet (creams, lotions, deodorants, etc.). In cosmetic products are usually dosed at concentrations of 0.05 % to 0.15 %. Formaldehyde is known for its toxic and allergic effect on skin. There is evidence for its possible carcinogenic effects. An easily accessible spectrophotometric method for determination of urotropine in cosmetic products was developed and validated. The method is based on the interaction of urotropine with chromotropic acid in sulfuric acid medium, forming a characteristic colored compound with a maximum light absorption at a wavelength of 570 nm. The LOD is 0.01 %. The LOQ is 0.02 %. Repeatability (SD) at urotropine concentration 0.10 % in basic foot care product with a homogeneous viscous consistency is 0.0022 %. Reproducibility at urotropine concentration 0,10 % in basic skincare product, expressed by RSD, is 1.51 %. The recovery at urotropine concentration 0.10 % in a cosmetic product is 97.17 % (90.00 % - 110.00 %) and at urotropine concentration 0.15 % is 98.33 % (95.00 % - 100.00 %). The developed method was applied for the analysis of five samples of cosmetic products for the hygiene of the feet, containing urotropine, as a preservative. The measured concentrations are within concentration interval permitted by law: from 0.11 % to 0.14 %. The validated spectrophotometric method for urotropine determination in foot care products is rapid, with sufficient sensitivity, accuracy and reproducibility and does not require complicated and expensive equipment. It is easily applied in control of cosmetic products containing the preservative urotropine. [ABSTRACT FROM AUTHOR]

Herbs are an ancient source of flavouring, aromatic compounds and medicines, not only for culinary application. The increasing interest in the powerful biological activity of plant phenolics and flavonoids outlined the necessity of determining their content in medicinal herbs. In this present study, a comparative evaluation of the polyphenol composition, antioxidant capacity and biological contaminants (microbes and other organisms) as major common contaminants in medicinal herbs from the Lamiaceal family to which belong: lemon balm (Melissa officinalis), sage (Salvia officinalis) and mint (Mentha piperita) were carried out. The total phenolic and total flavonoid contents in medicinal herbs ware evaluated using the Folin-Ciocalteu method, were determined with an aluminum chloride colorimetric assay. The 2,2-diphenyl-1-picryl hydrazyl (DPPH) radical scavenging effect of the herbs was measured also spectrophotometrically, like the total phenolic and total flavonoid contents. Microbiology was investigated using the current ISO methods. The present paper shows by the results of total phenolic and total flavonoid contents, antioxidant activity and biological contaminants in medicinal herbs that they must be relatively safe for the patient (consumer). [ABSTRACT FROM AUTHOR]

The synergistic solvent extraction of lanthanide ions with mixtures of 1-phenyl-3-methyl-4-benzoyl-pyrazol-5-one (HP) and the quaternary ammonium salt Aliquat 336 in chloride (QCl) or perchlorate (QClO4) forms in C6H6 was studied. The composition of the extracted species was determined as Q[LnP4] (Q+ is a quaternary ammonium salt cation). The values of the equilibrium constant were calculated. The extraction mechanism as well as the effect of the quaternary ammonium salt anion (Cl− or ClO4−) on the extraction process are discussed. The separation factors of the lanthanide ions were determined on the basis of the experimental data. Some trends in the lanthanide separation were established. [ABSTRACT FROM AUTHOR]

The object of our current study is to study the phytochemicalc contents in solid-liquid extraction of chicory (Cichorium intybus L.) dry leaves grown in Bulgaria. Cichorium intybus, commonly known as chicory, is well known as a coffee substitute but is also discretely used as the natural product in food industry and medicine throughout its long history. Solid-liquid extraction was performed by using the 50% aqueous ethanol for 120 min which results in concentration of phytochemical contents and the findings of our present results are well consistent with those obtained in other works. The chicory leaves were analysed for the content of tannin by titrimetric method; rutin was determined spectrophotometrically by using ammonium molybdate; the total phenolics was determined by the Folin-Ciocalteu assay and the total flavonoids was identified through the colorimetric reaction with aluminum (III) chloride. The content of total phenolics and total flavonoids of chicory varied between 2.71 mg GAE/mL for 10 min and 5.65 mg GAE/mL for 120 minutes and 0.84 mg CE/mL for 10 minutes and 2.45 mg CE/mL for 120 min. The content of rutin and tannins that varied within 0.71 percent for 10 minutes and 1.39 percent for 120 min of rutin and tannins was higher than that in 50% aqueous ethanol extract of Cichorium intybus L. for 120 min at 1.56% and 1.08% for 10 min, respectively. Extracts obtained positively correlated with their phenolic and flavonoid contents, rutin and tannins, respectively. Therefore, the complex of phytochemical active substance in dry leaves of Cichorium intybus L. offers lots of opportunities for future application in herbal medicine and nutrition industry to produce healthy food.

The purpose of this research was to investigate the potential interaction of conceptual representations and linguistic systems in the process of language acquisition. Language-thought interactions were studied in 80 American, 48 Finnish and 48 Polish preschool children. The research focused on the conceptual and linguistic development of space and time. The spatial and temporal conceptual tasks were designed to measure the transition from experimental to inferential knowledge of space/time representations. In the linguistic domain, comprehension and production tests were used to evaluate the children's capacity to understand mono- and bi-referential location in space and time, where mono-referential location involves a single referent object/event with intrinsic properties (e.g. in/on or past/non-past), and bi-referential location requires two or more referent objects/events and relative perspective (e.g. deictic front/back or before/after). The conceptual and linguistic tests revealed significant changes during the period from two to five years of age, and measures of conceptual development were correlated with measures of linguistic development. As spatial and temporal representations became more structured, children were able to move from mono- to bi-referential location. In a comprehension test, we discovered an interaction of language by dimension. Finnish children found spatial distinctions relatively easy and Polish children found temporal distinctions relatively easy. This interaction was expected on the basis of the relative complexity of the morpho-syntactic coding in the spatial and temporal systems of the two languages. However, the argument relating the timing of acquisition to the transparency versus opacity of the linguistic systems was not supported by the English language comparison. Finally, the Finnish children were relatively better able to accomplish the spatial conceptual tasks as compared to the Polish children. This finding is consistent with a developmental concept of linguistic relativity. In general, the research indicates that spatial and temporal linguistic systems and representational knowledge interact during development with the influence occurring in both directions. [ABSTRACT FROM AUTHOR]