scholarly journals Oil-Oxidizing Bacteria of Zaporozhskoye Reservoir

2016 ◽  
Vol 56 ◽  
pp. 65-72 ◽  
Author(s):  
Vladimir Yakovenko ◽  
Elena Fedonenko ◽  
Elena Zaychenko
Keyword(s):  
Water Pollution ◽  
Spatial Distribution ◽  
Oxidative Capacity ◽  
Sampling Time ◽  
Oil Products ◽  
Ecosystem Stability ◽  
Spring Season ◽  
Artificial Ecosystems ◽  
Self Cleaning ◽  
First Time

The study of oil-oxidizing bacteria number and activity has been carried out for the first time in contaminated with oil products and relatively clean areas of Zaporozhskoye reservoir in spring 2014. The research showed high potential oxidative capacity (POC) of water microflora that probably corresponds to the level of water pollution with oil products. During spring season the spatial distribution of oil bacteria as well as dependence on sampling time and water temperature were studied. Analysis of spatial distribution of oil-oxidizing bacteria numbers allowed to perform ranking of the sites with increasing of bacteria numbers in direction from the site "Near Kodaki water draw-off" to "Monastyrskiy island". Distribution of oil-oxidizing bacteria observed during the period of study reflects pollution and self-cleaning state of the sites. Using correlation analysis conclusion about connection of oil-oxidizing bacteria with diatoms "bloom" in spring has been made that shows importance of "bloom" for the realization of bacteria role in reservoir self-cleaning. The results are important for understanding the mechanisms of maintaining Zaporozhskoye reservoir ecosystem stability as well as for forecasting of pollution and self-purification processes and in general for the development and implementation of natural and artificial ecosystems sustainable development.

scholarly journals Host density predicts the probability of parasitism by avian brood parasites

2019 ◽  
Vol 374 (1769) ◽  
pp. 20180204 ◽  
Author(s):  
Iliana Medina ◽  
Naomi E. Langmore
Keyword(s):  
Spatial Distribution ◽  
Reproductive Success ◽  
Host Species ◽  
Field Data ◽  
Host Density ◽  
Brood Parasites ◽  
Parasitism Rates ◽  
Analyse Data ◽  
First Time ◽  
Determining Factor

The spatial distribution of hosts can be a determining factor in the reproductive success of parasites. Highly aggregated hosts may offer more opportunities for reproduction but can have better defences than isolated hosts. Here we connect macro- and micro-evolutionary processes to understand the link between host density and parasitism, using avian brood parasites as a model system. We analyse data across more than 200 host species using phylogenetic comparative analyses and quantify parasitism rate and host reproductive success in relation to spatial distribution using field data collected on one host species over 6 years. Our comparative analysis reveals that hosts occurring at intermediate densities are more likely to be parasitized than colonial or widely dispersed hosts. Correspondingly, our intraspecific field data show that individuals living at moderate densities experience higher parasitism rates than individuals at either low or high densities. Moreover, we show for the first time that the effect of host density on host reproductive success varies according to the intensity of parasitism; hosts have greater reproductive success when living at high densities if parasitism rates are high, but fare better at low densities when parasitism rates are low. We provide the first evidence of the trade-off between host density and parasitism at both macro- and micro-evolutionary scales in brood parasites. This article is part of the theme issue ‘The coevolutionary biology of brood parasitism: from mechanism to pattern’.

scholarly journals Hydrochemical Characteristics of the Surgut Reservoir Water Area Littoral Sections

2018 ◽  
Author(s):  
Keyword(s):  
Spatial Distribution ◽  
Power Plants ◽  
Thermal Power ◽  
Water Area ◽  
The Other ◽  
Anthropogenic Pressure ◽  
Taiga Zone ◽  
Thermal Power Plants ◽  
Reservoir Water ◽  
First Time

Cooling reservoirs of thermal power plants represent the special class of natural/ engineering systems with, on the one hand, natural geo/systems as one subsystem and, on the other hand, production/technological units as the other subsystem. Studying of these ecosystems’ functioning regularities seems to be helpful for water quality management and rational organization of water use. Besides, it is topical due to the low level of the relevant knowledge in the North of the Western Siberia. The authors for the first time in the Middle Ob Region have carried out a two-year session of monitoring of hydro/chemical indicators and temperature regime of the thermal power plants cooling reservoirs in the riparian stripe of water area. All previous investigations were done only by industrial water users within the frameworks of production monitoring in terms of three indicators in three points of the cooling reservoir water area downstream the power plant dam. Spatial distribution of concentrations of biogenic ions, salt composition, pH, organic matter, and metals in specific natural/technological system of the Surgut hthermal power plants’ reservoirs has been analyzed for the first time for the conditions of the Western Siberian taiga zone. Sources of anthropogenic pressure upon a water body have been identified. According the results of the indicators’ spatial distribution analysis three sections of the Surgut reservoir water area have been separated: a background section of the Chernaya River; a section upstream the dam with predominantly recreational character of the anthropogenic pressure; and a sectio0n downstream the dam with anthropogenic pressure of technological origin. According the outcomes of the correlation analysis indicators of the anthropogenic pressure character have been reveald.

scholarly journals Effect of Droplet Size and Counterions on the Spatial Distribution of Ions

2019 ◽  
Author(s):  
Victor Kwan ◽  
Styliani Consta
Keyword(s):  
Spatial Distribution ◽  
Reaction Mechanisms ◽  
Charge Carriers ◽  
Transfer Reactions ◽  
Spatial Distributions ◽  
Hydronium Ions ◽  
Ionic Atmosphere ◽  
Droplet Sizes ◽  
Charge Transfer Reactions ◽  
First Time

Electrosprayed droplets have emerged as a new environment for accelerating chemical reactions by orders of magnitude relative to their bulk analogues. Nevertheless the reaction mechanisms are still unknown. Unraveling the ion spatial distribution is critical as to where charge transfer reactions are likely to take place and as to their effect on the ionic atmosphere of macroions. Here we investigate the ion spatial distributions in aqueous droplets with diameters in the range of 5 nm to 16 nm with and without counterions using molecular dynamics. The charge carriers are Na, Cl ions and model hydronium ions. For the first time droplet sizes that are accessible to experimental scrutiny are modeled atomistically. <br>

Seismic characteristics of southeast Missouri as indicated by a regional telemetered microearthquake array

1976 ◽  
Vol 66 (6) ◽  
pp. 1953-1964 ◽  
Author(s):  
William Stauder ◽  
Mark Kramer ◽  
Gerard Fischer ◽  
Stephen Schaefer ◽  
Sean T. Morrissey
Keyword(s):  
Spatial Distribution ◽  
Active Faults ◽  
B Value ◽  
New Madrid Seismic Zone ◽  
Seismic Zone ◽  
Mississippi Embayment ◽  
Linear Dimensions ◽  
Seismic Characteristics ◽  
Active Zones ◽  
First Time

abstract A regional microearthquake network has been established in the New Madrid seismic zone to study better the seismic characteristics of this region. The network consists of 16 stations distributed on the borders of and within the head of the Mississippi embayment. The network has a location sensitivity for all earthquakes of mb ≧ 1 occurring within the network. A total of 330 earthquakes has been located within a 1.5° by 1.5° area inside the array during the first 21 months of operation. The spatial distribution of these hypocenters has identified for the first time in this region the existence of linear seismically active zones, corresponding presumably to seismically active faults. Several of these trend N40°E, parallel to the axis of the embayment. Others trend NW; these latter are parallel to and possibly are related to the crest of the Pascola arch which joins the Ozark uplift to the Nashville dome. The linear dimensions of the features identified thus far vary in length from about 25 km to about 100 km. The b value as determined by the number of earthquakes located thus far is about 0.8.

scholarly journals Weighing the two stellar components of the Galactic bulge

2018 ◽  
Vol 618 ◽  
pp. A147 ◽  
Author(s):  
M. Zoccali ◽  
E. Valenti ◽  
O. A. Gonzalez
Keyword(s):  
Spatial Distribution ◽  
Velocity Dispersion ◽  
Stellar Mass ◽  
Galactic Bulge ◽  
Relative Fraction ◽  
Mass Budget ◽  
Mass Profile ◽  
Main Components ◽  
First Time ◽  
Metallicity Distribution

Context.Recent spectroscopic surveys of the Galactic bulge have unambiguously shown that the bulge contains two main components, which are best separated by their iron content, but also differ in spatial distribution, kinematics, and abundance ratios. The so-called metal poor component peaks at [Fe/H] ∼ −0.4, while the metal rich component peaks at [Fe/H] ∼ +0.3. The total metallicity distribution function is therefore bimodal with a dip at [Fe/H] ∼ 0. The relative fraction of the two components changes significantly across the bulge area. Aims. We provide, for the first time, the fractional contribution of the metal poor and metal rich stars to the stellar mass budget of the Galactic bulge and its variation across the bulge area. Methods. This result follows from the combination of the stellar mass profile obtained empirically, by our group, from VISTA Variables in the Vía Láctea data, with the relative fraction of metal poor and metal rich stars, across the bulge area, derived from the GIRAFFE Inner Bulge spectroscopic Survey. Results. We find that metal poor stars make up 48% of the total stellar mass of the bulge, within the region |l| < 10, |b| < 9.5 and that the remaining 52% are made up of metal rich stars. The latter dominate the mass budget at intermediate latitudes |b| ∼ 4, but become marginal in the outer bulge (|b| > 8). The metal poor component is more axisymmetric than the metal rich component, and it is at least comparable and possibly slightly dominant in the inner few degrees. As a result, the metal poor component, which does not follow the main bar, is not marginal in terms of the total mass budget as previously thought, and this new observational evidence must be included in bulge models. While the trend of the total radial velocity dispersion follows the total stellar mass, when we examine the velocity dispersion of each component individually, we find that metal poor stars have higher velocity dispersion where they make up a smaller fraction of the stellar mass, and vice versa. This is due to the kinematical and spatial distribution of the two metallicity components being significantly different, as already discussed in the literature.

scholarly journals Buoyancy Assisted Janus Membrane Preparation by ZnO Interfacial Deposition for Water Pollution Treatment and Self‐cleaning

2019 ◽  
Vol 6 (21) ◽  
pp. 1901130 ◽  
Author(s):  
Tian‐Di Pan ◽  
Zong‐Jie Li ◽  
Da‐Hua Shou ◽  
Wan Shou ◽  
Jin‐Tu Fan ◽  
...  
Keyword(s):  
Water Pollution ◽  
Membrane Preparation ◽  
Pollution Treatment ◽  
Self Cleaning

Cytochemical localization of some polysaccharide components in the cell walls of Chalara elegans during its life cycle

1992 ◽  
Vol 38 (8) ◽  
pp. 828-837
Author(s):  
Eliane Dumas-Gaudot ◽  
Abdessamad Tahiri-Alaoui ◽  
Nicole Benhamou
Keyword(s):  
Spatial Distribution ◽  
Cell Walls ◽  
Pathogenic Fungus ◽  
Minor Component ◽  
Multilayered Structure ◽  
Electron Microscope Level ◽  
Cytochemical Localization ◽  
Chalara Elegans ◽  
A Minor ◽  
First Time

The occurrence of polysaccharides and sugars in the cell walls of the soil-borne pathogenic fungus Chalara elegans (deuteromycete) has been investigated at the electron microscope level, using cytochemical approaches based on the affinity of lectin or enzyme–gold complexes for some carbohydrates. Evidence for the presence of both β-1,4-glucans and chitinous components is reported here for the first time in the cell walls of chlamydospores, endoconidia, and hyphae. A minor component with N-acetyl-D-galactosamine residues is also detected in the cell walls and, as a storage product, in the cytoplasm. The spatial distribution of both cellulosic β-1,4-glucans and N-acetylglucosamine residues differs according to the fungal cells, and the present results give a more accurate description of the multilayered structure of the fungal walls (i.e., chlamydospores and hyphae). Key words: Chalara elegans, fungi, cell walls, gold cytochemistry.

Epibiosis and hyperepibiosis on Pagurus bernhardus (Crustacea: Decapoda) from the west Coast of Scotland

2012 ◽  
Vol 93 (5) ◽  
pp. 1351-1362 ◽  
Author(s):  
Gregorio Fernandez-Leborans ◽  
Patricia Dávila ◽  
Eva Cerezo ◽  
Cristina Contreras
Keyword(s):  
Spatial Distribution ◽  
West Coast ◽  
Sampling Area ◽  
The West ◽  
Diverse Range ◽  
Ciliate Protozoan ◽  
Invertebrate Species ◽  
Pagurus Bernhardus ◽  
First Time ◽  
Protozoan Species

The presence of a diverse range of epibionts was found on Pagurus bernhardus from the west coast of Scotland. The invertebrate species found on the shell inhabited by the crab were the hydrozoans Hydractinia echinata and Dycorine conferta, the cirripeds Balanus balanus and Balanus crenatus, the polychaetes Hydroides norvegica, Pomatoceros triqueter and Circeis armoricana, and the molluscs Hiatella arctica and Anomia ephippium. On the crab were observed the polychaete Circeis armoricana and the amphipod Podoceropsis nitida. In addition, on the gastropod shells occupied by P. bernhardus, ciliate protozoan species were found attached to the hydrozoan Dycorine conferta, this being hyperepibiosis. These ciliates were 6 suctorian (Conchacineta constricta, Corynophrya anisostyla, Actinocyathula homari, Actinocyathula crenata, Acineta sulcata and Acineta corophii), and one peritrich species (Zoothamnium sp.). This is the first time that this hyperepibiosis was observed. In contrast to the epibiont communities observed in previous surveys in the same sampling area, basibiont specimens without D. conferta did not show ciliate epibionts. The ciliate epibionts also were not present on the surface of the shell and crab in specimens with D. conferta; they only appeared in hyperepibiosis on the surface of the hydrozoan. The spatial distribution and abundance of the invertebrate epibiont species were analysed, as well as the morphology, taxonomy and distribution of the ciliate hyperepibionts.

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