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[en] Cupriavidus SRS is a metal resistant, rod shaped, gram negative bacteria that was isolated from a location with heavy metal contamination at the Department of Energy’s Savannah River Site in Aiken, South Carolina. This isolate has also been able to demonstrate antibiotic resistance and predatory behavior to other microorganisms, giving it a competitive advantage. The effect of bioaugmentation with Cupriavidus SRS and copper (Cu) uptake is not well understood, although multiple studies have analyzed this effect with other metal resistant bacteria. In this study, sediment from the AL1 outfall area will be inoculated with Cupriavidus SRS to analyze the effectiveness of the degradation of Cu.
[en] Sharks which are the top predators in the ocean food chain are still high in demand as delicacies (shark meat) in restaurants despite the efforts to protect them. Anyhow, sharks accumulate a significant amount of metals in their bodies. Hence, a study was carried out to examine the presence and concentration of heavy metals (Cd, Cu, Pb and Zn) in bamboo sharks (Chiloscyllium), the most commonly landed species. A total of 43 Chiloscyllium samples were collected from the local fishermen in Lumut, Perak. In this study, the two edible tissue samples, namely the muscle and fins were dissected and analysed using inductively coupled plasma – mass spectrometry (ICP-MS) following a Teflon bomb closed digestion with HNO3 acid. Based on the results, the concentration of heavy metals in muscle tissues arranged in a diminution order is Zn > Cu > Pb > Cd. Meanwhile, the concentration pattern of metals in fin tissues followed the Zn > Pb > Cu > Cd sequence. The average concentration of metals in the fin tissues was higher than that of muscle tissues. All metals examined were associated with the sharks’ length and weight, whereby the findings also indicated that all metals exhibited positive correlation except for Pb concentration in muscle and Zn concentration in fin tissues. The Pollution Load Index (PLI) was used as the predictor to assess the contamination status in the tissue samples. The average PLI value calculated for the muscle and fin tissues ranged between 3.2 and 12.4, respectively. These values also indicated that the level of contamination is very much under control, hence, no monitoring is needed. Therefore, all findings from this study may be used as a reference for future studies, especially on the west coast of Peninsular Malaysia waters. (author)
[en] One of the perspective directions for the restoration of contaminated lands is the use of humic-based compounds. The structure of these types of compounds causes to form compounds that dissolve in water combining heavy metals, radionuclides, pesticides and other toxicants. The use of humic-based compounds causes to the land clearing and causes to the increasing of its productivity. During experiments it has been determined that humates have more effective impact with the form of enriched microelements.
[en] Asinibacterium sp. strains OR43 and OR53 belong to the phylum Bacteroidetes and were isolated from subsurface sediments in Oak Ridge, TN. Both strains grow at elevated levels of heavy metals. Here, we present the closed genome sequence of Asinibacterium sp. strain OR53 and the draft genome sequence of Asinibacterium sp. strain OR43. Authors:
[en] Mitochondria are cellular powerhouses as well as metabolic and signaling hubs regulating diverse cellular functions, from basic physiology to phenotypic fate determination. It is widely accepted that reactive oxygen species (ROS) generated in mitochondria participate in the regulation of cellular signaling, and that some mitochondria chronically operate at a high ROS baseline. However, it is not completely understood how mitochondria adapt to persistently high ROS states and to environmental stressors that disturb the redox balance. Here we will review some of the current concepts regarding how mitochondria resist oxidative damage, how they are replaced when excessive oxidative damage compromises function, and the effect of environmental toxicants (i.e. heavy metals) on the regulation of mitochondrial ROS (mtROS) production and subsequent impact.
[en] The comprehensive sensory, analytic-chemical, physical-chemical and microbiological analyzes of numerous water samples taken from upper and lower layers of the largest rivers of Azerbaijan - Kur and Araz were carried out. Sources of the anthropogenic emissions polluting these cross-border rivers are defined. The dose rate of ionizing radiation in nearby territories along the watercourse of these rivers and on minerals of water samples was measured and the levels of all types of ionizing radiation were estimated.
[en] Specific activities were measured along a sediment profile collected nearby to the Yara River mouth at the Guacanayabo Gulf. X-Ray fluorescence was also used to measure K, Ca, Ti, Fe, Mn, Cu, Ni, Co, Pb and Zn in this profile and in surface samples along the coastline near of estuary Yara. The measurement of the specific activities evidenced strong mixture process, Heavy metal concentrations have similar values along the profile, excepting Pb that has the greatest values at the surface. All the samples have different pollution levels mainly of Zn, Pb, Cu and Co elements. With the calculated index (Geo-accumulation (Igeo) and Enrichment Factor (EF) index) this coastal environment can be classified as unpolluted to moderately pollute. According to the NOOA indicators, bay levels of before mentioned metals, mainly Cu and Co, were considered as potentially toxic, therefore, further investigations are strongly recommended. An increase in the level of pollutants was evidenced in relation to previous study performed in 2008. The obtained results have shown the influence of the sewer city system, which collects spills of several activities, agricultural use of metal-containing fertilizers and pesticides, and the emission of untreated sewage and also metal contaminated effluents from medical use and industrial units. (Author)
[en] Interspecies, inter-tissue and interspatial dissimilarities of trace metals in particular body parts of Saccostrea cucullata, Thais clavigera and Nerita chameleon from the east Johor coastal waters were compared. Metals of interest includes Pb, Cd, Zn, Cu, Mn, Co, Se and Sr. Bivalve mollusk S. cucullata evidenced to be a worthy bioindicator for Zn and Cu while the two gastropod molluscs, T. clavigera for Cd and Se, and N. chameleon for Pb, Mn and Sr. The prominent concentration of metals originate in T. clavigera may be the outcome of biomagnification transfer from the S. cucullata on which they feed while for N. chameleon, it might be resulting from their herbivorous feeding behavior on algae on rocks which they graze. The metal accumulation patterns indicate consistent enrichment of essential metals in soft tissue. Values of operculum to tissue ratio (OTR) and shell to tissue (STR) higher than unity in T. clavigera indicate that operculum had higher affinities for Pb, Mn and Se while shell had higher affinities for Co and Sr. In N. chameleon, values of OTR and STR higher than unity displayed that operculum and shell had similar higher affinities for Co and Sr and Cd, Co and Sr, respectively. Significant interspatial variations (p<0.05 and p<0.01) in trace metals were noted. Assessment of metal concentration with maximum permissible limits of toxic metals in food shown the values were well within safety levels, except for Zn in S. cucullata that need to be monitored. (author)
[en] YbNiP is a stoichiometric heavy-fermion Kondo-lattice system with a Kondo temperature of 8 K 1. This system is situated in the close vicinity of a ferromagnetic (FM) quantum-critical point (QCP) and can be tuned to the FM QCP by substituting a small amount of phosphorous by arsenic 1. Recently, nine field-induced Lifshitz transitions (LTs) have been proposed in YbNiP 2 from the results of the transport and thermodynamic measurements, revealing a complicated electronic band structure of the system. We have performed ultrasonic measurements on single crystals of YbNiP to deepen the understanding of these phase transitions. We found clear features in the ultrasound velocity (v) and the attenuation () corresponding to crystal-electric-field and Kondo effects. However, we detected no or very small anomalies in v or at the expected FM phase transition in the longitudinal c33 mode, reflecting a weak coupling of the corresponding symmetry strain to the magnetic structure. On the other hand, pronounced features were identified at the proposed Lifshitz transitions at roughly 0.4, 6 and 7 T clearly demonstrating the different character of these transitions.