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Open access

Viktoria Volodina, Natalia Karygina, Olga Popova, Elmira Popova, Mariia Grushko and Nadezhda Fedorova

Abstract

The toxicological study conducted revealed high concentrations of hydrocarbons and highly toxic heavy metals in the liver and subcutaneous fat of the Caspian seal. The increased toxicant level in the fat, as compared to the liver, pointed to the disorder of organism purification processes, leading to chronic polytoxicosis and disorders of the histological structure of the internals. The studies of the morphofunctional state of the stomach of the Caspian pinnipeds revealed the following disorders: hemorrhages, edemata and necrosis of the mucous membrane, and replacement of glandular tissue with the connective tissue. The study of the small intestine of the seals identified the symptoms of catarrhal desquamatory enteritis. Epithelium dystrophy and desquamation were noted, in particular at the tops of the villi. Different types of colitis (acute, ulcerative, chronic) were found in the large intestine of the seals. Dystrophic and necrotic changes of hepatocytes were identified in the liver tissue, which pointed to the liver cell failure. The nature and extent of pathological changes in the internals and tissues of the studied animals point to the functional depression of the digestive system.

Open access

Linda Abi-Ayad, Sidi-Mohammed Bahae-Ddine Ghezlaoui, Nassereddine Belkhouche and José Morillo Aguado

Abstract

This work brings an evaluation of the quality of littoral zone of Algerian in two neighbouring port coasts, namely, Honaine and Beni Saf, chosen as significant discharge sites. This was followed by a comparison of the state of these coasts with those of the Mediterranean coastal areas. The study was conducted in all seasons in the year 2011−2012 by measuring the hydrological physicochemical parameters (pH, temperature, turbidity and salinity) and using sea lettuce Ulva lactuca as significant ‘biomarker of the quantity of metal contaminants (Cd, Pb, Cu and Zn)’. Harvesting of Ulva and the seawater samples were performed in each season in three stations, characterised by discharges of waste and industrial water and saline discharges from the recent installation of desalination in Honaine. The metal concentrations in seawater showed significant variations between stations and the harvest season, resulting in the appearance of pollution of Cd, Pb, Cu and Zn. Also this result was manifested in Ulva in the station S1 (Beni Saf) and S2 (Honaine-beach) with the exception of copper. These results have exceeded tolerable international standards.

Open access

Svetlana Volodarets, Aleksandr Glukhov and Irina Zaitseva

Abstract

The study of phytoncide activity of biogenic volatile organic compounds of woody plants is one of the most important areas of research in plant ecology in urban lands. The aim of this work is to investigate the dependence of the phytoncide activity of some woody plant species from meteorological factors in the urban environment in the steppe zone of Ukraine. The objectives of the investigation were 28 species of trees and shrubs. The air temperature is indicated to be a major factor for drought-resistant and some medium drought-resistant species (Populus simonii Carrière, Armeniaca vulgaris L., Robinia pseudoacacia L., Acer pseudoplatanus L., Malus niedzwetzkyana Dieck). The phytoncide activity of low and medium drought-resistant species (Viburnum opulus L., Acer sacharinnum L.) depends on air humidity and total monthly precipitation. The obtained results make it possible to predict changes in the phytoncide activity of woody plants, when selecting the assortment of species for phyto-optimization of technogenic environment.

Open access

Benamar Belgherbi, Kheloufi Benabdeli and Kamel Mostefai

Abstract

The methods applied in Algeria for the prevention and fight against the fires remain fairly traditional and have proved to be ineffective in reducing the disastrous impact of this phenomenon. However, the aim of this work is to analyse a forest ecosystem that is fairly representative of the whole of the forests in Algeria, on plan risk and vulnerability of the environment for a better control of risk. Using modern geomatics techniques to map the degree of risk of fires and analysis the space: like satellite imagery spatial data and Geographic Information Systems (GIS).The Guetarnia forest in western Algeria has been retained; seven thematic maps have been developed and have helped to develop a sensitivity map to depict the fire risk.

Open access

Radoslav Bujnovský

Abstract

The primary aim of the article is to obtain an overview of benefits from the actual use of inland water ecosystem services (ESSs) in Slovakia. The evaluation, which includes both surface water and groundwater, is primarily focused on demand side. Methods for assessing the benefits of the most prevalent ESSs, designated by Common International Classification of Ecosystem Services (CICES classification) v. 4.3, are described and discussed. The evaluation is performed at the level of 10 sub-basins to which available data are allocated. In the absence of necessary data or the impossibility of allocating them to sub-basins, the benefit from the use of some ESSs is estimated at the level of whole Slovak territory. The use of ESSs valuation in practice, especially with regard to water protection of surface water and groundwater, is discussed. The evaluation of benefits from ESSs of inland waters in Slovakia so far does not allow direct use of obtained results for proposal of measures within river basin management plans as suggested by several authors. Main reason is the input data availability and quality. At the present time, the significance of the ESSs evaluation may rather lie in the awareness of the value that human society gains from the use of inland waters. It becomes more evident that increase in environmental awareness alone is not sufficient in terms of the protection of ecosystems and their services. To achieve unambiguous and lasting improvement in this area, it is necessary to address the deeper causes, closely related to human thinking and behaviour.

Open access

Olena Blinkova and Tetyana Shupova

Abstract

Assessment of correlations and comparisons of diversity indices between birds communities and vegetation composition of the forest ecosystem is an important subject of synecological research to identify the intensity of human impact on the flora and fauna in megalopolis. Urban recreation is one of the major causes of violation of the structural and functional integrity of the forest ecosystem. Studies on avian complex and phytocoenosis have focused on the impact of urban recreation on the soil surface, compositions of trees, shrub and herbaceous layers and species, trophic and ecological compositions of nesting-birds and feeding-birds communities. This article compares the measurement of the diversity of bird communities and forestry vegetation (diversity indices, dominance indices, evenness indices) in the natural and semi-natural forests of the Kyiv city on a gradient of recreational transformation. The stands formed consist of Quercus robur L., Carpinus betulus L., Acer platanoides L., Tilia cordata L., Ulmus glabra Huds., Fraxinus excelsior L. and Prunus avium L. The floristic list comprised 65 grass species. A total of 49 species of avifauna were found, including 44 species that were protected by the Bern, Bonn and Washington Conventions. There were significant correlations between vertical and horizontal heterogeneities of tree distribution and abundance, species richness and nesting density of birds. The interrelationship between species diversity of birds and floristic richness was also confirmed.

Open access

Michal Greguš, Pavlo Ďurč, Julia Lačná, František Foreti and Peter Kubáň

Abstract

In this work, various parameters that influence the ionic content and pH of exhaled breath condensate in of the noninvasive diagnosis of gastroesophageal reflux disease were studied. Exhaled breath condensate samples were collected using a miniature and inexpensive sampling device. Capillary electrophoresis with contactless conductometric detection was used to monitor the ionic content of exhaled breath condensate. Background electrolyte composed of 20 mM of 2-(N-Morpholino)ethanesulfonic acid, 20 mM of L-Histidine, 2 mM of 18-Crown-6 and 30 M of cetyltrimethylammonium bromide facilitated the rapid separation of anions and cations, both in less than 2 minutes. The possibility of contamination of the exhaled breath condensate by saliva is discussed in detail. The day-to-day repeatability (n=5) of the ionic content and pH of the exhaled breath condensate was studied and was satisfactory, reflecting mainly the physiological variability

Open access

Dana Moravcová and Josef Planeta

Abstract

The monolithic capillary columns (0.1 mm x 150 mm) prepared by the acidic hydrolysis of tetramethoxysilane (TMOS) in the presence of polyethylene glycol (PEG) and urea were modified by zwitterionic stationary phases and evaluated under HILIC separation conditions by employing a mixture containing nucleosides and nucleotides. The polymeric layer of zwitterions did not affect the high separation efficiency of the original silica monolith. The prepared zwitterionic columns exhibited high separation efficiencies in a range 61,000-289,000 theoretical plates/m for a 2- methacryloyloxyethyl phosphorylcholine-based stationary phase and in a range 59,000-135,000 theoretical plates/m for a [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide-based stationary phase under optimal separation conditions. The grafted layer of zwitterions on the silica monolithic surface also significantly improved the separation selectivity to compounds of interest

Open access

Kateřina Hamáková, David Potěšil, Ondřej Bernatik, Igor Červenka, Matěj Rádsetoulal, Vitězslav Bryja and Zbyněk Zdráhal

Abstract

The focus of this paper is the human Dishevelled 3 protein (hDvl3), an essential component of the Wnt signalling pathway that contributes to their regulation. Mass spectrometry-based analysis of hDvl3 phosphorylations induced by eight associated kinases was performed revealing several dozens of phosphorylation sites. The main outcome of this study was the description of Dvl phosphorylation “patterns” induced by individual kinases

Open access

Anikό Kilár, Ágnes Dornyel, Viktor Sándor, Ferenc Kilár and Béla Kocsis

Abstract

Much interest is at present focused on bacterial endotoxins, also known as lipopolysaccharides (LPS), as they are responsible for the development of clinical symptoms of Gram-negative sepsis which is the leading cause of death in intensive care units. Endotoxicity is associated with the special phosphoglycolipid part of LPS, termed lipid A. Main challenges in the structural elucidation of lipid A arise from its amphiphilic character and inherent heterogeneity. A mass spectrometrybased de novo method combined with reversed-phase liquid chromatography for the detailed structural characterization of complex lipid A mixtures (obtained by mild acid hydrolysis of LPS) from different bacterial sources has been developed. Tandem mass spectrometric measurements were performed with an electrospray-ionisation quadrupole time-of-flight (ESI-Q-TOF) mass spectrometer in both negative- and positive-ionization modes in order to explore fragmentation pathways. It was found that characteristic product ions in the positive-ion mode could be used for the unambiguous assignment of the phosphorylation site, whereas the use of both ionization modes provided consistent and/or complementary information about the fatty acyl distribution between the two glucosamine moieties of lipid A. Since the immunostimulatory (advantageous) vs. proinflammatory (endotoxic) effect of the lipid A is closely related to the fine chemical structure, our relatively simple structural elucidation strategy could offer great potential in the bioanalysis of native lipid A samples and lipid A-based vaccines