خيارات البحث
النتائج 1301 - 1310 من 1,324
Toxic effect of tetracycline exposure on growth, antioxidative and genetic indices of wheat (Triticum aestivum L.) النص الكامل
2011
Xie, Xiujie | Zhou, Qixing | Lin, Dasong | Guo, Jianmian | Bao, Yanyu
Introduction More attention has been paid to tetracycline contamination in view of its rapid increasing concentration in the environment. Therefore, it is important to set up rapid, simple, and accurate methods for monitoring tetracycline ecotoxicity. Methods In the present study, a hydroponics experiment was conducted to examine toxic effects of tetracycline at the concentration range of 0.5 to 300 mg L⁻¹ on growth, antioxidative, and genetic indices of wheat (Triticum aestivum L.). Results The results indicated that tetracycline at 0.5-10 mg L⁻¹ could stimulate seed germination, cell mitotic division, and growth of wheat seedlings and did not induce a significant increase in the activity of antioxidative enzymes. However, tetracycline at the high concentrations (10-300 mg L⁻¹) could significantly inhibit these parameters in the concentration-dependent manner, including germination percentage (≥100 mg L⁻¹), shoot height (≥100 mg L⁻¹), root length (≥50 mg L⁻¹), and mitotic index (≥50 mg L⁻¹), and increased the activity of antioxidative enzymes (≥25 mg L⁻¹) in the dose-dependent manner, including superoxide dismutase, catalase, and peroxidase. Tetracycline at 5 mg L⁻¹ and above significantly augmented chromosome aberration frequency and malondialdehyde (MDA) content. On the other hand, MDA has positive correlation with the inhibition rates of seed germination, root length, shoot length, mitotic index, and antioxidative enzyme activities. Conclusion Tetracycline may have potential physiological, biochemical, and genetic toxicity to plant cells, and chromosome aberration and MDA might be sensitive bioindicators for tetracycline contamination than the other plant characteristics.
اظهر المزيد [+] اقل [-]The performance of nature reserves in capturing the biological diversity on Hainan Island, China النص الكامل
2011
Wu, Ruidong | Ma, Guangzhi | Long, Yongcheng | Yu, Jiehua | Li, Shining | Jiang, Haisheng
Purpose The performance of nature reserves depends on the degree to which they represent a region's full biodiversity. Here, we conducted a study on Hainan Island, China, to assess how well Hainan's biodiversity features were captured by existing nature reserves. We also explored the driving forces behind the current protection pattern so as to provide guidelines for improving the island's conservation system. Methods We integrated the information on nature reserves, ecological variables, and human activities into a spatial database, then assessed the performance of nature reserves in representing natural variation, vegetation types, and species, and examined the impacts of human activities and land ownership on the current protection pattern. Results About 8.4% of Hainan Island was protected by nature reserves; the coverage was geographically biased toward its central mountainous areas with higher elevation, rugged terrain, and fertile soils. We found that 60% of the environmental units and 39.4% of the natural vegetation types had more than 10% of their area protected, respectively. Lowlands tended to have higher animal species richness, and the protection for endangered species was less efficient. Nature reserve coverage was negatively correlated with amount of converted habitats, human population density, and road density, and 82.4% of the total reserved area was allocated on state-owned land. Conclusions Nature reserve coverage was not enough to capture lowlands biodiversity features. The current protection pattern was significantly driven by several major conservation targets, human development, planning methods, and land ownership. To improve its conservation system, Hainan should enhance protection in the north and northeast plains and coastal regions, implement systematic planning approaches to define clear visions for guiding future conservation actions, and develop flexible management and funding mechanisms toward sustainable use of natural resources.
اظهر المزيد [+] اقل [-]Statistical analysis and isotherm study of uranium biosorption by Padina sp. algae biomass النص الكامل
2011
Khani, Mohammad Hassan
Introduction The application of response surface methodology is presented for optimizing the removal of U ions from aqueous solutions using Padina sp., a brown marine algal biomass. Methods Box-Wilson central composite design was employed to assess individual and interactive effects of the four main parameters (pH and initial uranium concentration in solutions, contact time and temperature) on uranium uptake. Results and discussion Response surface analysis showed that the data were adequately fitted to second-order polynomial model. Analysis of variance showed a high coefficient of determination value (R ² = 0.9746) and satisfactory second-order regression model was derived. Conclusion The optimum pH and initial uranium concentration in solutions, contact time and temperature were found to be 4.07, 778.48 mg/l, 74.31 min, and 37.47°C, respectively. Maximized uranium uptake was predicted and experimentally validated. The equilibrium data for biosorption of U onto the Padina sp. were well represented by the Langmuir isotherm, giving maximum monolayer adsorption capacity as high as 376.73 mg/g.
اظهر المزيد [+] اقل [-]Remédiation à la pollution par la chlordécone aux Antilles النص الكامل
2011
Jannoyer M. (ed.) | Lordinot J. (ed.) | Quénéhervé P.
Mosses as biomonitors of POPs pollution : spatial trends of PAH concentrations in mosses from France, Switzerland and Spain النص الكامل
2011
Foan, Louise | Leblond, Sébastien | Thöni, Lotti | Santamaria, Jesus Miguel | Simon, Valérie | Chimie Agro-Industrielle (CAI) ; Institut National de la Recherche Agronomique (INRA)-Ecole nationale supérieure des ingénieurs en arts chimiques et technologiques (ENSIACET) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT) | Muséum national d'Histoire naturelle (MNHN) | FUB - Research Group for Environmental Monitoring (SWITZERLAND) | Universidad de Navarra [Pamplona] (UNAV) | International Cooperative Programme on Effects of Air Pollution on Natural Vegetation and Crops (ICP Vegetation). CHE.
Session 3b: Heavy metals/N/POPs | International audience
اظهر المزيد [+] اقل [-]Use of the MicroResp (TM) method to assess pollution-induced community tolerance to metals for lotic biofilms النص الكامل
2011
Tlili, Ahmed | Maréchal, Marjorie | Montuelle, Bernard | Volat, Bernadette | Dorigo, Ursula | Berard, Annette
Use of the MicroResp (TM) method to assess pollution-induced community tolerance to metals for lotic biofilms النص الكامل
2011
Tlili, Ahmed | Maréchal, Marjorie | Montuelle, Bernard | Volat, Bernadette | Dorigo, Ursula | Berard, Annette
Understanding the ecological status of aquatic ecosystems and the impact of anthropogenic contamination requires correlating exposure to toxicants with impact on biological communities. Several tools exist for assessing the ecotoxicity of substances, but there is still a need for new tools that are ecologically relevant and easy to use. We have developed a protocol based on the substrate-induced respiration of a river biofilm community, using the MicroRes (TM) technique, in a pollution-induced community tolerance approach. The results show that MicroRes (TM) can be used in bioassays to assess the toxicity toward biofilm communities of a wide range of metals (Cu, Zn, Cd, Ag, Ni, Fe, Co, Al and As). Moreover, a community-level physiological profile based on the mineralization of different carbon substrates was established. Finally, the utility of MicroRes (TM) was confirmed in an in-situ study showing gradient of tolerance to copper correlated to a contamination gradient of this metal in a small river. A modified MicroRes (TM) technique as a tool for measuring induced tolerance to heavy metals of a microbial biofilm community.
اظهر المزيد [+] اقل [-]Use of the MicroResp (TM) method to assess pollution-induced community tolerance to metals for lotic biofilms النص الكامل
2011
Tlili, Ahmed | Maréchal, Marjorie | Montuelle, Bernard | Volat, Bernadette | Dorigo, Ursula | Berard, Annette
Understanding the ecological status of aquatic ecosystems and the impact of anthropogenic contamination requires correlating exposure to toxicants with impact on biological communities. Several tools exist for assessing the ecotoxicity of substances, but there is still a need for new tools that are ecologically relevant and easy to use. We have developed a protocol based on the substrate-induced respiration of a river biofilm community, using the MicroRes (TM) technique, in a pollution-induced community tolerance approach. The results show that MicroRes (TM) can be used in bioassays to assess the toxicity toward biofilm communities of a wide range of metals (Cu, Zn, Cd, Ag, Ni, Fe, Co, Al and As). Moreover, a community-level physiological profile based on the mineralization of different carbon substrates was established. Finally, the utility of MicroRes (TM) was confirmed in an in-situ study showing gradient of tolerance to copper correlated to a contamination gradient of this metal in a small river. A modified MicroRes (TM) technique as a tool for measuring induced tolerance to heavy metals of a microbial biofilm community.
اظهر المزيد [+] اقل [-]Use of the MicroResp™ method to assess pollution-induced community tolerance to metals for lotic biofilms النص الكامل
2011
Tlili, Ahmed | Marechal, Marjorie | Montuelle, Bernard | Volat, Bernadette | Dorigo, Ursula | Bérard, Annette
Understanding the ecological status of aquatic ecosystems and the impact of anthropogenic contamination requires correlating exposure to toxicants with impact on biological communities. Several tools exist for assessing the ecotoxicity of substances, but there is still a need for new tools that are ecologically relevant and easy to use. We have developed a protocol based on the substrate-induced respiration of a river biofilm community, using the MicroResp™ technique, in a pollution-induced community tolerance approach. The results show that MicroResp™ can be used in bioassays to assess the toxicity toward biofilm communities of a wide range of metals (Cu, Zn, Cd, Ag, Ni, Fe, Co, Al and As). Moreover, a community-level physiological profile based on the mineralization of different carbon substrates was established. Finally, the utility of MicroResp™ was confirmed in an in-situ study showing gradient of tolerance to copper correlated to a contamination gradient of this metal in a small river.
اظهر المزيد [+] اقل [-]Use of the MicroResp™ method to assess pollution-induced community tolerance to metals for lotic biofilms النص الكامل
2011
Tlili , Ahmed (Institut National de Recherche en Sciences et Technologies pour l'Environnement et l'Agriculture, Lyon cedex 09(France). UR MAEP) | Maréchal , Marjorie (Institut National de Recherche en Sciences et Technologies pour l'Environnement et l'Agriculture, Lyon cedex 09(France). UR MAEP) | Montuelle , Bernard (Institut National de Recherche en Sciences et Technologies pour l'Environnement et l'Agriculture, Lyon cedex 09(France). UR MAEP) | Volat , Bernadette (Institut National de Recherche en Sciences et Technologies pour l'Environnement et l'Agriculture, Lyon cedex 09(France). UR MAEP) | Dorigo , Ursula (INRA , Thonon-Les-Bains (France). UMR 0042 Centre Alpin de Recherche sur les Réseaux Trophiques des Ecosystèmes limniques) | Berard , Annette (INRA , Avignon (France). UMR 1114 Environnement Méditerranéen et Modélisation des Agro-Hydrosystèmes )
Understanding the ecological status of aquatic ecosystems and the impact of anthropogenic contamination requires correlating exposure to toxicants with impact on biological communities. Several tools exist for assessing the ecotoxicity of substances, but there is still a need for new tools that are ecologically relevant and easy to use. We have developed a protocol based on the substrate-induced respiration of a river biofilm community, using the MicroResp™ technique, in a pollution-induced community tolerance approach. The results show that MicroResp™ can be used in bioassays to assess the toxicity toward biofilm communities of a wide range of metals (Cu, Zn, Cd, Ag, Ni, Fe, Co, Al and As). Moreover, a community-level physiological profile based on the mineralization of different carbon substrates was established. Finally, the utility of MicroResp™ was confirmed in an in-situ study showing gradient of tolerance to copper correlated to a contamination gradient of this metal in a small river. A modified MicroResp™ technique as a tool for measuring induced tolerance to heavy metals of a microbial biofilm community
اظهر المزيد [+] اقل [-]Use of the MicroResp method to assess pollution-induced community tolerance to metals for lotic biofilms النص الكامل
2011
Tlili, Ahmed | Marechal, Marjorie | Montuelle, Bernard | Volat, Bernadette | Dorigo, Ursula | Berard, Annette, A. | Structures et propriétés d'architectures moléculaire (SPRAM - UMR 5819) ; Institut Nanosciences et Cryogénie (INAC) ; Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS) | Centre Alpin de Recherche sur les Réseaux Trophiques et Ecosystèmes Limniques (CARRTEL) ; Institut National de la Recherche Agronomique (INRA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]) | Milieux aquatiques, écologie et pollutions (UR MALY) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Laboratoire d'Ecologie Alpine (LECA) ; Université Joseph Fourier - Grenoble 1 (UJF)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS) | Environnement Méditerranéen et Modélisation des Agro-Hydrosystèmes (EMMAH) ; Avignon Université (AU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
[Departement_IRSTEA]Eaux [TR1_IRSTEA]BELCA | International audience | A modified MicroRespÔ technique as a tool for measuring induced tolerance to heavy metals of a microbial biofilm community. a b s t r a c t Understanding the ecological status of aquatic ecosystems and the impact of anthropogenic contamination requires correlating exposure to toxicants with impact on biological communities. Several tools exist for assessing the ecotoxicity of substances, but there is still a need for new tools that are ecologically relevant and easy to use. We have developed a protocol based on the substrate-induced respiration of a river biofilm community, using the MicroRespÔ technique, in a pollution-induced community tolerance approach. The results show that MicroRespÔ can be used in bioassays to assess the toxicity toward biofilm communities of a wide range of metals (Cu, Zn, Cd, Ag, Ni, Fe, Co, Al and As). Moreover, a community-level physiological profile based on the mineralization of different carbon substrates was established. Finally, the utility of MicroRespÔ was confirmed in an in-situ study showing gradient of tolerance to copper correlated to a contamination gradient of this metal in a small river.
اظهر المزيد [+] اقل [-]Best practices in the agrochemical industry
2011
Cheremisinoff, Nicholas P. | Rosenfeld, Paul E. (Paul Edward)
"Best practices in the agrochemical industry covers the impact of agrochemicals in food and water supplies, and provides an overview of agrochemical residues and their health impacts as well as mitigation strategies. It includes extensive data tables covering USA and international regulatory frameworks for exposure to pesticides, including EPA, NIOSH, OSHA, WHO and ACGIH. Health impacts are explored, such as the pollution of drinking water with atrazine, trichloropropane and DBCP and the risks associated with these substances, including miscarriages and infertility. The authors also explore the effect of pesticide residues in food, including contaminants in organic food, and they present a case study concerning worker pesticide exposure. This book is a guide and professional reference for those involved in the agrochemical industry and it details safer manufacturing processes and procedures to limit pollution"--Page 4 of cover.
اظهر المزيد [+] اقل [-]Nucleic acid biosensors for environmental pollution monitoring
2011
Mascini, Marco | Palchetti, Ilaria
Annotation <div>Nucleic acids are the fundamental building blocks of life and are found in all living things. In recent years, their functions have been shown to extend beyond the Watson-Crick base pair recognition of complementary strands. Molecules (known as aptamers) consisting of 40-50 nucleotides have been isolated that are able to bind a broad range of molecules with high affinity and specificity. The molecules recognized by aptamers range from small organic molecules to proteins, cells and even intact viral particles. Catalytic DNA molecules called NAzymes (RNAzyme or DNAzyme) have also been shown to exist and, when combined with aptamers, are known as aptazymes. These biomolecules can be used to develop smart and innovative biosensors for environmental analysis. Monitoring of contaminants in the air, water and soil is a key component in understanding and managing risks to human health and ecosystems. This, in conjunction with the time and cost involved in traditional chemical analysis, means there is a growing need for simple, rapid, cost-effective and portable screening methods. Biosensors are compact devices which complement current field screening and monitoring methods. This book demonstrates the incredible opportunities that nucleic acids can offer to environmental analytical chemistry. The chapters: show how nucleic acids have a pivotal role in the development of smart biosensors for environmental monitoring; describe the development of biosensors based on aptamers and NAzymes for the detection of organic and inorganic pollutants; deal with the use of nucleic acid based biosensors for environmental toxicity screening, and detail the use of nanomaterials, as well as miniaturization and lab-on-a-chip technologies, for nucleic acid based biosensing systems.</div>
اظهر المزيد [+] اقل [-]Effects of seawater acidification on early development of the intertidal sea urchin Paracentrotus lividus, seawater carbonate chemistry and biological processes النص الكامل
2011
Moulin, Laure | Catarino, Ana Isabel | Claessens, Thomas | Dubois, Philippe
Effects of seawater acidification on early development of the intertidal sea urchin Paracentrotus lividus, seawater carbonate chemistry and biological processes النص الكامل
2011
Moulin, Laure | Catarino, Ana Isabel | Claessens, Thomas | Dubois, Philippe
The effect of pH ranging from 8.0 to 6.8 (total scale - pHT) on fertilization, cleavage and larval development until pluteus stage was assessed in an intertidal temperate sea urchin. Gametes were obtained from adults collected in two contrasting tide pools, one showing a significant nocturnal pH decrease (lowest pHT = 7.4) and another where pH was more stable (lowest pHT = 7.8). The highest pHT at which significant effects on fertilization and cleavage were recorded was 7.6. On the contrary, larval development was only affected below pHT 7.4, a value equal or lower than that reported for several subtidal species. This suggests that sea urchins inhabiting stressful intertidal environments produce offspring that may better resist future ocean acidification. Moreover, at pHT 7.4, the fertilization rate of gametes whose progenitors came from the tide pool with higher pH decrease was significantly higher, indicating a possible acclimatization or adaptation of gametes to pH stress.
اظهر المزيد [+] اقل [-]Seawater carbonate chemistry in tide pools near Aber, Crozon penisula (France), 2009 النص الكامل
2011
Moulin, Laure | Catarino, Ana Isabel | Claessens, Thomas | Dubois, Philippe
Seawater carbonate chemistry duirng experiments with sea urchin Paracentrotus lividus, 2011 النص الكامل
2011
Moulin, Laure | Catarino, Ana Isabel | Claessens, Thomas | Dubois, Philippe
Effects of seawater acidification on early development of the intertidal sea urchin Paracentrotus lividus (Lamarck 1816) النص الكامل
2011
Moulin, Laure | Catarino, Ana Isabel | Claessens, Thomas | Dubois, Philippe
The effect of pH ranging from 8.0 to 6.8 (total scale – pHT) on fertilization, cleavage and larval development until pluteus stage was assessed in an intertidal temperate sea urchin. Gametes were obtained from adults collected in two contrasting tide pools, one showing a significant nocturnal pH decrease (lowest pHT=7.4) and another where pH was more stable (lowest pHT=7.8). The highest pHT at which significant effects on fertilization and cleavage were recorded was 7.6. On the contrary, larval development was only affected below pHT 7.4, a value equal or lower than that reported for several subtidal species. This suggests that sea urchins inhabiting stressful intertidal environments produce offspring that may better resist future ocean acidification. Moreover, at pHT 7.4, the fertilization rate of gametes whose progenitors came from the tide pool with higher pH decrease was significantly higher, indicating a possible acclimatization or adaptation of gametes to pH stress.
اظهر المزيد [+] اقل [-]Seawater carbonate chemistry, fertilization rate and biological processes of sea urchin Paracentrotus lividus during experiments, 2011 النص الكامل
2011
Moulin, Laure | Catarino, Ana Isabel | Claessens, Thomas | Dubois, Philippe
The effect of pH ranging from 8.0 to 6.8 (total scale - pHT) on fertilization, cleavage and larval development until pluteus stage was assessed in an intertidal temperate sea urchin. Gametes were obtained from adults collected in two contrasting tide pools, one showing a significant nocturnal pH decrease (lowest pHT = 7.4) and another where pH was more stable (lowest pHT = 7.8). The highest pHT at which significant effects on fertilization and cleavage were recorded was 7.6. On the contrary, larval development was only affected below pHT 7.4, a value equal or lower than that reported for several subtidal species. This suggests that sea urchins inhabiting stressful intertidal environments produce offspring that may better resist future ocean acidification. Moreover, at pHT 7.4, the fertilization rate of gametes whose progenitors came from the tide pool with higher pH decrease was significantly higher, indicating a possible acclimatization or adaptation of gametes to pH stress.
اظهر المزيد [+] اقل [-]