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[en] Highlights: • Trace Elements varied depending on the location of the sampling stations. • Five trace elements (Zn, Fe, As, Al, Cu) are ubiquitous. • Trace Elements in the western Mediterranean Sea displayed a north-to-south gradient. - Abstract: A study on Trace Elements (TE) from sea urchin gonads has been conducted in the western Mediterranean Sea. Contamination data were used to determine a Trace Method Pollution Index (TEPI). TE concentrations varied considerably depending on the location of the sampling stations. The results showed that five trace elements (Zn, Fe, As, Al, Cu) are ubiquitous. The geographical area considered (Corsica) represents an important range of environmental conditions and types of pressure that can be found in the western Mediterranean Sea. TEPI was used to classify the studied sites according to their degree of contamination and allowed reliable comparison of TE contamination between local and international sites. TE contamination of the western Mediterranean Sea displayed a north-to-south gradient, from the Italian coasts down through the insular Corsican coasts to the north African littoral. Due to the increasing environmental pressure on the Mediterranean Sea, a regular monitoring of TE levels in marine organisms is necessary to prevent any further environmental deterioration.
[en] Highlights: • Seagrass coverage has increased in six contiguous estuaries in Southwest Florida • Increases in coverage have occurred in response to sustained nutrient management • Patterns of change vary, as not every estuary was equally impacted by development • The most impacted estuaries had the greatest recovery of seagrass coverage • Lag periods between nutrient reductions and system responses can be years - Abstract: In Southwest Florida, a variety of human impacts had caused widespread losses of seagrass coverage from historical conditions. St. Joseph Sound and Clearwater Harbor lost approximately 24 and 51%, respectively, of their seagrass coverage between 1950 and 1999, while Tampa Bay and Sarasota Bay had lost 46% and 15%, respectively, of their seagrass coverage between 1950 and the 1980s. However, over the period of 1999 to 2016, the largest of the six estuaries, Tampa Bay, added 408 ha of seagrass per year, while the remaining five estuaries examined in this paper added approximately 269 ha per year. In total, seagrass coverage in these six estuaries increased 12,171 ha between the 1980s and 2016. Focused resource management plans have held the line on nitrogen loads from non-point sources, allowing seagrass resources to expand in response to reductions in point source loads that have been implemented over the past few decades.
[en] Highlights: • Low concentrations of trace metals in the muscle tissue for all studied marine species • Absence of clear patterns for all studied species and elements • Metal concentrations were mainly higher in the Gulf of Lions than in the Bay of Biscay. - Abstract: Concentrations of 6 trace metals (Ag, Cd, Cu, Ni, Pb, Zn) in the muscle of 2 sharks (Galeus melastomus and Scyliorhinus canicula), 4 teleosts (Helicolenus dactylopterus, Lepidorhombus boscii, Micromesistius poutassou and Phycis blennoides) and 1 crustacean (Nephrops norvegicus) were compared between the Bay of Biscay (Atlantic Ocean) and the Gulf of Lions (Mediterranean Sea). Although average concentrations and the trace element pollution index were generally higher in the Gulf of Lions, significant differences between the two ecosystems were only found for Zn for Helicolenus dactylopterus, and for Ag and Cu for the crustacean N. norvegicus. Moreover, some relationships between trophic level or size and metal concentrations were found for these two species. The absence of clear pattern may result from the blurring effect of contamination and excretion that may act differentially for all species and all elements.
[en] Highlights: • Carboxylesterase activity is a better alternative to acetylcholinesterase in clams. • Ruditapes decussatus displays high detoxification capacity. • Carboxylesterases are very sensitive to in vitro exposures chlorpyrifos oxon. • Antioxidant enzymes and lactate dehydrogenase are well represented in clam gills and digestive gland. - Abstract: Acetylcholinesterase (AChE) is a reliable biomarker of pesticide exposure although in clams this activity is often very low or undetectable. Carboxylesterases (CEs) exhort several physiological roles, but also respond to pesticides. Searching for an AChE alternative, baseline CE activities were characterised in Ruditapes decussatus gills and digestive glands using five substrates suggestive of different isozymes. The long chain p-nitrophenyl butyrate and 1-naphthyl butyrate were the most sensitive. In the digestive gland, their kinetic parameters (Vmax and Km) and in vitro sensitivity to the organophosphorus metabolite chlorpyrifos oxon (CPX) were calculated. IC50 values, in the pM–nM range, suggest a high protection efficiency of CE-related enzymes towards CPX neurotoxicity. Other targeted enzymes were: activities of glutathione reductase, glutathione peroxidase, catalase, glutathione S-transferases (GSTs) and lactate dehydrogenase in gills and digestive glands. The high GSTs activity and CE/AChE ratio suggests that R. decussatus has a great capacity for enduring pesticide exposure.
[en] Highlights: • Inter-estuarine OCPs and PCBs differences were observed in polychaete tissues. • Intra-estuarine spatial and temporal OCPs and PCBs differences were also evident. • Small individuals accumulate higher levels of OCPs and PCBs compared to larger worms. • OCPs and PCBs levels showed important sediment-polychaeta relationships. - Abstract: Southwest Atlantic (SWA) estuaries have been historically impacted by industrial and agricultural activities that represent an important source of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs). Intraspecific differences in OCPs and PCBs levels were evaluated in the benthic polychaete Laeonereis culveri from SWA estuaries (Samborombón; Mar Chiquita; Quequén Grande and Bahía Blanca) at different spatio-temporal scales. Regarding inter- and intra-estuarine spatial comparisons polychaetes showed significant differences in OCPs/PCBs levels (p p < 0.05). OCPs/PCBs concentrations were negatively correlated with animal weight, but this covariable was not relevant on differences observed. OCPs/PCBs levels in polychaetes showed strong relationships with those of sediments, being suitable for estuarine biomonitoring studies. Seasonal and body-size differences found in OCPs and PCBs levels in tissues reveal the importance of these factors for intra-estuarine monitoring.
[en] Highlights: • G. obtusa hosts a diverse community of microorganisms dominated by Proteobacteria. • Transplantation to eutrophic conditions did not cause significant changes in sponge microbiome structure. • Sponges from eutrophic site showed higher abundance of the ammonia oxidation gene marker. - Abstract: Sponges harbor a great diversity of symbiotic microorganisms. However, environmental stresses can affect this partnership and influence the health and abundance of the host sponges. In Bolinao, Pangasinan, Philippines, chronic input of organic materials from mariculture activities contributes to a eutrophic coastal environment. To understand how these conditions might affect sponge-microbial partnerships, transplantation experiments were conducted with the marine sponge Gelliodes obtusa. High-throughput sequencing of 16S rRNA revealed that the associated microbial community of the sponges did not exhibit significant shifts after six weeks of transplantation at a eutrophic fish farm site compared to sponges grown at a coral reef or a seagrass area. However, sponges at the fish farm revealed higher abundance of the amoA gene, suggesting that microbiome members are responsive to increased ammonium levels at the site. The stable association between G. obtusa and its microbiome indicates that the sponge holobiont can withstand eutrophication pressure from mariculture.
[en] Highlights: • A new method for polycyclic aromatic compounds (PACs) determination in sediments was optimized. • PAHs, Nitro-PAHs, Quinones were determined in sediments through SDME/GC–MS. • The developed method showed a good applicability. • Simultaneous quantification of PAHs, nitro-PAHs and quinones in sediments samples - Abstract: Conventional methods for determination of polycyclic aromatic compounds (PACs) in sediments usually require large sample sizes (grams) and solvent volumes (at least 100 mL) through the employment of Soxhlet extraction, which is both time (hours) and energy consuming, among other disadvantages. We developed a new analytical protocol for the determination of PACs in sediments using microextraction, which requires small sample masses (25 mg), 500 μL of acetonitrile-dichloromethane mix and sonication for 23 min, followed by GC–MS analysis. The method was validated using the certified reference material SRM 1941b – NIST organic marine sediment, as well as internal deuterated standards. Seventeen PAHs, seven nitro-PAHs and one quinone were detected and quantified. The mean concentrations were 90.4 ng g−1 for PAHs, 179.2 ng g−1 for nitro-PAHs and 822.5 ng g−1 for quinones. The proposed method showed good sensitivity, linearity, precision and accuracy for the determination of PAC in sediments samples.
[en] The Experimental Power Reactors (RDE) development plan is not only based on the consideration of technological and safety aspects, but also based on social, economic, cultural and environmental aspects. Based on social aspects, the development plan can be interpreted differently within the community based on their level of knowledge and perception. The aim of the study was to determine the level of acceptance of the surrounding communities of the Puspiptek Serpong Region towards the development of RDE. The methodology used was the literature study followed by a survey with proportional respondents. From the results of the questionnaire analysis showed that 64 % of respondents stated that they knew BATAN had operated a nuclear reactor, while 19 % of them were not aware of the information and those who did not answer was around 17 %. Most of the respondents stated that the information source of knowledge about BATAN was obtained from their participation in discussion events by 18.7 %, then 17.7 % through TV and counselling at 16.3 %. There were 75 % of respondents who agreed to the RDE development plan to meet electricity needs, while those who disagreed were 7 % and the rest 18 % did not answer. Around 20.3 % of respondents thought that the presence of RDE would cause electricity prices to decline, some 19.2 % thought about job creation and 17.5 % of them understood that RDE did not produce any air pollution. The disagreement of RDE development plan mostly due to the fears of an accident/leak and radioactive pollution and also assume that other electric power plants are still sufficient. (author)
[en] The natural circulation is considered in the design of emergency passive core cooling system in a nuclear power plant. In that context, FASSIP-02 experimental loop is designed in order to investigate the characteristics of the natural circulation in a closed loop. This paper simulates the various operational conditions of FASSIP-02. The objective is to obtain the best operational conditions of FASSIP02 once it is built. For that purpose, the simulation is done with different condition of the heater power, the pipe insulation and the expansion tank's valve using RELAP5 code. The simulation time is up to 50,000 s. The simulation results show that until 50,000 s the steady state condition could not be achieved yet when the heater power greater than 10 kW. The pipe insulation causes faster increase of the water temperature inside the pipe and the induced water flow rate, as well. While, if the expansion tank's valve is closed during the operation, the pressure inside the loop would increase, faster when the heater power is higher and could reach the critical pressure. It is concluded that in all cases to avoid the saturation condition, the heater power should be maintained lower than 10 kW, especially when the loop pipe is insulated. (author)
[en] As the telecom industry is looking for new opportunities to improve its commercial potential by introduction 5G technology, energy industry is rising as potential area for deployment of smart Internet of Things (IoT) solutions and ICT. Following the recent achievements in digitalisation of energy industry, smart phones and mobile application, smart metering, data analytics and artificial intelligence popularity, as well as the human decision-making and behavior based on purely rational choice, we are proposing the consumer centric model for energy efficiency. The model is considering the current communication network features, Wi-Fi and 4G/5G networks and a possibility to influence the consumer behavior in residential segment (households) and achieve reasonable energy savings. Following this model adapted to the Macedonian energy and telecom market specifics, we are estimating that the investment risk versus the potential energy reduction is worth to be further considered by deployment of the proposed system architecture. (author)