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The short-term associations of weather and air pollution with emergency ambulance calls for paroxysmal atrial fibrillation Texte intégral
2017
Vencloviene, Jone | Babarskiene, Ruta Marija | Dobozinskas, Paulius | Dedele, Audrius | Lopatiene, Kristina | Ragaisyte, Nijole
A circadian variation in the cardiovascular parameters has been detected. It is plausible that the influence of the environment varies during different periods of the day. We investigated the association between daily emergency ambulance calls (EC) for paroxysmal atrial fibrillation (AF) that occurred during the time intervals of 8:00–13:59, 14:00–21:59, and 22:00–7:59, and weather conditions and exposure to CO and PM₁₀. We used Poisson regression to explore the association between the risk of EC for AF and environmental variables, adjusting for seasonal variation. Before noon, the risk was associated with an IQR (0.333 mg/m³) increase in CO at lag 2–6 days above the median (RR = 1.15, P = 0.002); a protective impact of CO on previous day was observed (RR = 0.91, P = 0.018). During 14:00–21:59, a negative effect of air temperature below 1.9 °C (lag 2–3 days) was detected (per 10 °C decrease: RR = 1.17, P = 0.044). At night, the elevated risk was associated with wind speed above the median (lag 2–4 days) (per 1-kt increase: RR = 1.07, P = 0.001) and with PM₁₀ at lag 2–5 days below the median (per IQR (7.31 μg/m³) increase: RR = 1.21, P = 0.002). Individuals over 65 years of age were more sensitive to air pollution, especially at night (CO lag 2–3 days < median, per IQR (0.12 mg/m³) increase: RR = 1.14, P = 0.045; PM₁₀ lag 2–5 days < median, per IQR increase: RR = 1.32, P = 0.001). The associations of air pollution and other environmental variables with acute events may be analyzed depending on the time of the event.
Afficher plus [+] Moins [-]Analysis of ecotoxic influence of waste from the biomass gasification process Texte intégral
2017
Hawrot-Paw, Małgorzata | Koniuszy, Adam | Mikiciuk, Małgorzata | Izwikow, Monika | Stawicki, Tomasz | Sędłak, Paweł
The purpose of this research was evaluation of the effect of soil contamination with waste coming from biomass gasification on chosen indicators of its biological activity, growth and development of spring barley, and change of physiological parameters of the plant. Chromatographic content and basic rheological parameters of the substances under research were also analyzed. Liquid wastes, tar, and mixture of tar and engine oil were introduced to the soil in the amount of 100 mg kg⁻¹ DM soil. Based on the conducted research, it was ascertained that the changes in the number and activity of soil microorganisms were determined by the type of waste and its dose. Individual groups of microorganisms showed different sensitivity to the presence of pollution; however, the impact of tar and engine oil mixture was generally more disadvantageous. Presence of contaminants in the soil limited the growth of roots and aboveground parts of spring barley, especially when the dose was 10,000 mg kg⁻¹ DM soil. The unfavorable impact of waste on photosynthesis efficiency on assimilation pigment synthesis and water content in the plant was recorded.
Afficher plus [+] Moins [-]Effect of ferrous sulfate and nitrohumic acid neutralization on the leaching of metals from a combined bauxite residue Texte intégral
2017
Ren, Jie | Liu, Jidong | Chen, Juan | Liu, Xiaolian | Li, Fasheng | Du, Ping
Bauxite residue neutralization is intended to open opportunities for revegetation and reuse of the residue. Ferrous sulfate (FS) and nitrohumic acid (NA) were two kinds of materials studied for pH reduction of the residue from 10.6 to 8.3 and 8.1, respectively. The effects of FS and NA on the leaching of metals from a combined bauxite residue were investigated by using sequential and multiple extraction procedures. Neutralization with FS and NA restricted the leaching of Al, V, and Pb from the residue but promoted the leaching of Fe, Cu, Mn, and Ni, consistent with the changes in the potentially mobile fractions. With the exceptions of Pb and Ni, leaching of metals increased during a 10-day extraction period. However, the maximum leaching of Al, V, Pb, Fe, Cu, Mn, and Ni from neutralized bauxite residue were 0.46 mg/L, 59.3, 12.9, 167, 95.3, 15.5, and 14.5 μg/L, respectively, which were under the corresponding limits in the National Standard (GB/T 14848-93). Although it is necessary to consider the continued leaching of metals during neutralization, both maximum and accumulation leaching concentrations of metals from a combined bauxite residue were too low to pose a potential environmental risk.
Afficher plus [+] Moins [-]Preparation of magnetic MIL-101 (Cr) for efficient removal of ciprofloxacin Texte intégral
2017
Bayazit, Şahika Sena | Danalıoğlu, Selen Tuğba | Abdel Salam, Mohamed | Kerkez Kuyumcu, Özge
Metal organic frameworks are widely used as adsorbent materials in recent years. In this study, the most prepared metal organic framework MIL-101 was prepared by hydrothermal method and featured magnetic property using co-precipitation method Fe₃O₄. Then, the prepared composite (MIL-101/Fe₃O₄) was first characterized using XRD, FTIR, SEM-EDS, and surface area analysis, then was used for the adsorptive removal of the most used antibiotic, ciprofloxacin (CIP). The effect of different adsorption variables which may affect the removal of CIP by MIL-101/Fe₃O₄ was investigated, as well as their adsorbent quantity, initial CIP concentration, pH, temperature, and contact time. The non-linear Langmuir and Freundlich isotherm were applied to experimental data. It was observed that rising solution temperature decreases adsorption efficiency, as the maximum adsorption uptake value was 63.28 mg g⁻¹ at 298 K and 22.93 mg g⁻¹ at 313 K, indicating the exothermic nature of the adsorption. The adsorption was studied kinetically and found to follow the pseudo-second-order kinetic model. The desorption of CIP from the MIL-101/Fe₃O₄ was investigated using three different eluents, and the results showed that phosphate-buffered solution was the most effective desorption eluent. Graphical abstract Schematic diagram of the preparation steps of MIL-101/Fe3O4
Afficher plus [+] Moins [-]Response of low-molecular-weight organic acids in mangrove root exudates to exposure of polycyclic aromatic hydrocarbons Texte intégral
2017
Jiang, Shan | Xie, Feng | Lu, Haoliang | Liu, Jingchun | Yan, Chongling
Low-molecular-weight organic acids (LMWOAs) represent an important component of root exudates. They play a pivotal role in the degradation of polycyclic aromatic hydrocarbons (PAHs) in sediments as they influence PAH bioavailability and degrader colonization. This study examined variations of LMWOAs in mangrove root exudates (Aegiceras corniculatum and Kandelia obovata) after exposure in phenanthrene and pyrene solution for 7 and 40 days, respectively. After 7 days of treatment, total root exudates and six types of LMWOA in root exudates from both mangrove species were enhanced. The largest increase was found in oxalic acid, i.e., the dominant component in determined LMWOAs. Coupled with the enhancement in LMWOA exudation rates, root metabolism intensities, measured as the dehydrogenase activity, increased. In contrast, after 40 days of exposure, the exudation rate of total LMWOAs had dropped markedly in PAH-contaminated groups compared to the control, indicating that PAHs negatively impacted root metabolism and activities due to their toxicity. The largest decrease was also found in oxalic acid, suggesting that the biological reactions related with oxalic acid are vulnerable under PAH stresses.
Afficher plus [+] Moins [-]Zero-valent iron particles for PCB degradation and an evaluation of their effects on bacteria, plants, and soil organisms Texte intégral
2017
Ševců, Alena | El-Temsah, YehiaS. | Filip, Jan | Joner, ErikJ. | Bobčíková, Kateřina | Černík, Miroslav
Two types of nano-scale zero-valent iron (nZVI-B prepared by borohydride reduction and nZVI-T produced by thermal reduction of iron oxide nanoparticles in H₂) and a micro-scale ZVI (mZVI) were compared for PCB degradation efficiency in water and soil. In addition, the ecotoxicity of nZVI-B and nZVI-T particles in treated water and soil was evaluated on bacteria, plants, earthworms, and ostracods. All types of nZVI and mZVI were highly efficient in degradation of PCBs in water, but had little degradation effect on PCBs in soil. Although nZVI-B had a significant negative impact on the organisms tested, treatment with nZVI-T showed no negative effect, probably due to surface passivation through controlled oxidation of the nanoparticles.
Afficher plus [+] Moins [-]Comparative toxicity of seven rare earth elements in sea urchin early life stages Texte intégral
2017
Trifuoggi, Marco | Pagano, Giovanni | Guida, Marco | Palumbo, Anna | Siciliano, Antonietta | Gravina, Maria | Lyons, Daniel M. | Burić, Petra | Levak, Maja | Thomas, Philippe J. | Giarra, Antonella | Oral, Rahime
The widespread use of rare earth elements (REEs) in a number of technological applications raises unanswered questions related to REE-associated adverse effects. We have previously reported on the multiple impact of some REEs on the early life stages of the sea urchin Paracentrotus lividus. The present investigation was to evaluate REE toxicity to early life stages in two unrelated sea urchin species, Sphaerechinus granularis and Arbacia lixula. The comparative toxicities were tested of seven REEs, namely yttrium, lanthanum, cerium, neodymium, samarium, europium and gadolinium as chloride salts at concentrations ranging from 10⁻⁷ to 10⁻⁴ M. The evaluated endpoints included developmental defects and cytogenetic anomalies in REE-exposed embryos/larvae, and decreased fertilization success and offspring damage following sperm exposure. The results showed different toxicity patterns for individual REEs that varied according to test species and to treatment protocol, thus showing toxicity scaling for the different REEs. Further, the observed effects were compared with those reported for P. lividus either following embryo or sperm exposures. S. granularis showed a significantly higher sensitivity both compared to A. lixula and to P. lividus. This study provides clear-cut evidence for distinct toxicity patterns among a series of REEs. The differences in species sensitivity at micromolar REE levels may warrant investigations on species susceptibility to impacts along polluted coasts.
Afficher plus [+] Moins [-]Plastisphere in action: evidence for an interaction between expanded polystyrene and dunal plants Texte intégral
2017
Poeta, Gianluca | Fanelli, Giuliano | Pietrelli, Loris | Acosta, Alicia T. R. | Battisti, Corrado
Among the many threats that can be recorded on sandy beaches, plastic litter represents a serious problem for these complex and endangered ecosystems. Expanded polystyrene (EPS) is increasingly abundant as a form of plastic litter in natural environments, particularly along shores and waterways. Nevertheless, despite the great number of scientific articles concerning the impact of litter on animal species, there are still no research focusing on the interaction between this type of beach litter and other biodiversity components. In this work, we reported the first evidence of interactions between EPS and living plants along a sandy beach of Tyrrhenian central Italy. We sampled 540 EPS items, mainly deriving from fishery activities (>75%). We obtained evidence for an interaction between EPS and plants: about 5% of items resulted perforated or have roots of three species (Phragmites australis, Spartina versicolor, Anthemis maritima). Apparently, we did not observed a relationship between plants and EPS items size. More research is needed to assess if the plant assemblage growing on EPS is random or if peculiar substrate exerts some sort of selection on the plant community.
Afficher plus [+] Moins [-]Evaluation of atrazine degradation applied to different energy systems Texte intégral
2017
Moreira, Ailton J. | Pinheiro, Bianca S. | Araújo, André F. | Freschi, Gian P. G.
Atrazine is an herbicide widely used in crops and has drawn attention due to potential pollution present in soil, sediment, water, and food. Since conventional methods are not potentially efficient to persistent degradation of organic compounds, new technology has been developed to remove them, especially practices utilizing advanced oxidation processes (AOPs). This work aims to evaluate the use of different energies (ultraviolet (UV), microwaves (MW), and radiations (MW-UV)) to the herbicide atrazine through the process of photo-oxidation. These systems found degradation rates of around 12% (UV), 28% (MW), and 83% (MW-UV), respectively, with time intervals of 120 s. After the photolytic processes, the samples were analyzed at a wavelength scanning the range of 190 to 300 nm, where the spectral analysis of the signal was used to evaluate the degradation of atrazine and the appearance of some other peaks (degradation products). The spectrum evaluation resulting from photolytic processes gave rise to a new signal which was confirmed by chromatography. This spectrum indicated the possible pathway of atrazine degradation by the process of photolytic MW-UV, generating atrazine-2-hydroxy, atrazine-desethyl-2-hidroxy, and atrazine-desisopropyl-2-hydroxy. The process indicated that in all situations, chloride was present in the analytic structure and was substituted by a hydroxyl group, which lowered the toxicity of the compound through the photolytic processMW-UV. Chromatographic analysis ascertained these preliminary assessments using spectrophotometry. It was also significantly observed that the process can be optimized by adjusting the pH of the solution, which was evident by an improvement of 10% in the rate of degradation when subjected to a pH solution equal to 8.37.
Afficher plus [+] Moins [-]Agroforestry: a sustainable environmental practice for carbon sequestration under the climate change scenarios—a review Texte intégral
2017
Abbas, Farhat | Hammad, Hafiz Mohkum | Shah, Fahad | Cerdà, Artemio | Rizwan, Muhammad | Farhad, Wajid | Ehsan, Sana | Bakhat, Hafiz Faiq
Agroforestry is a sustainable land use system with a promising potential to sequester atmospheric carbon into soil. This system of land use distinguishes itself from the other systems, such as sole crop cultivation and afforestation on croplands only through its potential to sequester higher amounts of carbon (in the above- and belowground tree biomass) than the aforementioned two systems. According to Kyoto protocol, agroforestry is recognized as an afforestation activity that, in addition to sequestering carbon dioxide (CO₂) to soil, conserves biodiversity, protects cropland, works as a windbreak, and provides food and feed to human and livestock, pollen for honey bees, wood for fuel, and timber for shelters construction. Agroforestry is more attractive as a land use practice for the farming community worldwide instead of cropland and forestland management systems. This practice is a win–win situation for the farming community and for the environmental sustainability. This review presents agroforestry potential to counter the increasing concentration of atmospheric CO₂ by sequestering it in above- and belowground biomass. The role of agroforestry in climate change mitigation worldwide might be recognized to its full potential by overcoming various financial, technical, and institutional barriers. Carbon sequestration in soil by various agricultural systems can be simulated by various models but literature lacks reports on validated models to quantify the agroforestry potential for carbon sequestration.
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