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Inoculation with endophytic Bacillus megaterium H3 increases Cd phytostabilization and alleviates Cd toxicity to hybrid pennisetum in Cd-contaminated aquatic environments Полный текст
2017
Li, Ya | Han, Hui | He, Lin Yan | Wang, Qi | Sheng, Xia Fang
A hydroponic culture experiment was performed to investigate the effects of endophytic Bacillus megaterium H3 on the plant biomass, Cd accumulation and tolerance of hybrid pennisetum, and the mechanisms involved in the different levels of Cd-contaminated aquatic environments. Strain H3 significantly increased the plant growth (ranging from 13 to 71 %) and total Cd uptake (ranging from 41 to 160 %) but decreased Cd translocation factors of hybrid pennisetum treated with 0–20 μM Cd compared with the controls. Furthermore, most of Cd (71–77 %) was accumulated in the roots of the bacterial-inoculated hybrid pennisetum. Notably, strain H3 could significantly increase the production of oxalic and propanedioic acids (ranging from 18 to 188 %) but decrease the production of phytochelatins of hybrid pennisetum compared to the controls under different levels of Cd stress. The live bacterial-induced increase in organic acid production and decrease in phytochelatins production by hybrid pennisetum might be responsible for the increased plant growth, root Cd accumulation, and Cd toxicity alleviation of the plant under different levels of Cd stress. The results highlight that hybrid pennisetum plus endophytic B. megaterium H3 may be utilized for biomass production and Cd phytostabilization of the plant in the different levels of Cd-contaminated aquatic environments.
Показать больше [+] Меньше [-]Environmental risk assessment of blight-resistant potato: use of a crop model to quantify nitrogen cycling at scales of the field and cropping system Полный текст
2017
Young, MarkW. | Mullins, Ewen | Squire, GeoffreyR.
Environmental risk assessment of GM crops in Europe proceeds by step-wise estimation of effect, first in the plant, then the field plot (e.g. 10–100 m⁻²), field (1000–10,000 m⁻²) and lastly in the environment in which the crop would be grown (100–10,000 km²). Processes that operate at large scales, such as cycling of carbon (C) and nitrogen (N), are difficult to predict from plot scales. Here, a procedure is illustrated in which plot scale data on yield (offtake) and N inputs for blight resistant (both GM and non-GM) and blight-susceptible potato are upscaled by a model of crop resource use to give a set of indicators and metrics defining N uptake and release in realistic crop sequences. The greatest potential damage to environment is due to loss of N from the field after potato harvest, mainly because of the large quantity of mineral and plant matter, high in N, that may die or be left in the field. Blight infection intensifies this loss, since less fertiliser N is taken up by plants and more (as a proportion of plant mass) is returned to the soil. In a simulation based on actual crop sequences, N returns at harvest of potato were raised from 100 kg ha⁻¹ in resistant to 150 kg ha⁻¹ in susceptible varieties subject to a 40% yield loss. Based on estimates that blight-resistant types would require ~20% of the fungicide applied to susceptible types, introduction of resistant types into a realistic 6-year cropping sequence would reduce overall fungicide use to between 72 and 54% depending on the inputs to other crops in the sequence.
Показать больше [+] Меньше [-]Prevalence of chromosomal aberrations in Argentinean agricultural workers Полный текст
2017
Bianco, GracielaEugenia | Suarez, Eva | Cazon, Lauro | de la Puente, TeresitaBeatriz | Ahrendts, MarceloRafael Benitez | De Luca, JulioCésar
Prevalence of chromosomal aberrations in Argentinean agricultural workers Полный текст
2017
Bianco, GracielaEugenia | Suarez, Eva | Cazon, Lauro | de la Puente, TeresitaBeatriz | Ahrendts, MarceloRafael Benitez | De Luca, JulioCésar
Little is known about biosecurity measures and toxic effects during pesticide application in the province of Jujuy, Argentina, particularly concerning the protective measures and mixture of pesticides used by rural workers. We carried out an observational study of agricultural workers from Jujuy (76 exposed subjects and 53 controls) to investigate the prevalence of chromosomal aberrations (CAs) in human lymphocytes as well as the activity level of acetylcholinesterase (AChE) in red blood cell erythrocytes. Whole blood samples (5 mL) were collected in heparinized Vacutainer tubes for cytogenetic analysis and erythrocyte cholinesterase activity determination according to Ellman’s method. Cytogenetic results showed a significant CA increase in pesticide-exposed individuals as compared with controls (4.20 ± 0.15 vs. 1.00 ± 0.05, respectively; p < 0.001), suggesting that pesticides are clastogenic agents causing DNA damage. Erythrocyte cholinesterase activity was significantly lower in exposed individuals, evidencing the possible occurrence of perturbations in blood as well as neurotoxicity in pesticide sprayers. These results suggest the need for periodic biomonitoring of these biomarkers together with education and training of occupational workers for the safe application of potentially harmful pesticides.
Показать больше [+] Меньше [-]Prevalence of chromosomal aberrations in Argentinean agricultural workers Полный текст
2017
Bianco Sadir, Graciela Eugenia | Suarez, Eva | Cazon, Lauro | de la Puente, Teresita Beatriz | Ahrendts, Marcelo Rafael Benitez | de Luca, Julio Cesar
Little is known about biosecurity measures and toxic effects during pesticide application in the province of Jujuy, Argentina, particularly concerning the protective measures and mixture of pesticides used by rural workers. We carried out an observational study of agricultural workers from Jujuy (76 exposed subjects and 53 controls) to investigate the prevalence of chromosomal aberrations (CAs) in human lymphocytes as well as the activity level of acetylcholinesterase (AChE) in red blood cell erythrocytes. Whole blood samples (5 mL) were collected in heparinized Vacutainer tubes for cytogenetic analysis and erythrocyte cholinesterase activity determination according to Ellman’s method. Cytogenetic results showed a significant CA increase in pesticide-exposed individuals as compared with controls (4.20 ± 0.15 vs. 1.00 ± 0.05, respectively; p < 0.001), suggesting that pesticides are clastogenic agents causing DNA damage. Erythrocyte cholinesterase activity was significantly lower in exposed individuals, evidencing the possible occurrence of perturbations in blood as well as neurotoxicity in pesticide sprayers. These results suggest the need for periodic biomonitoring of these biomarkers together with education and training of occupational workers for the safe application of potentially harmful pesticides. | Fil: Bianco Sadir, Graciela Eugenia. Universidad Nacional de Jujuy. Facultad de Ciencias Agrarias; Argentina | Fil: Suarez, Eva. Universidad Nacional de Jujuy. Facultad de Ciencias Agrarias; Argentina | Fil: Cazon, Lauro. Universidad Nacional de Jujuy. Facultad de Ciencias Agrarias; Argentina | Fil: de la Puente, Teresita Beatriz. Universidad Nacional de Jujuy. Facultad de Ciencias Agrarias; Argentina | Fil: Ahrendts, Marcelo Rafael Benitez. Universidad Nacional de Jujuy. Facultad de Ciencias Agrarias; Argentina | Fil: de Luca, Julio Cesar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; Argentina
Показать больше [+] Меньше [-]Chemometrics applied to cathodoluminescence images: a new approach to classify pre-Columbian artefacts from northern Peru Полный текст
2017
Ammari, Faten | Del-Solar-Velarde, Nino | Chapoulie, Rémy | Bousquet, Bruno
In most archaeological researches, ceramic cathodoluminescence images are conventionally exploited in a descriptive way (paste colour, inclusions). In this study, a new approach was employed: image’s RGB histograms were used in order to differentiate several ceramics recently discovered at the archaeological site of San José de Moro located in northern Peru. Cathodoluminescence coupled with chemometric methods appears as a good method to characterize and particularly to produce a systematic classification of complex materials such as archaeological ceramics. Our results were compared with the archaeological and classical background knowledge and this allowed confirming that Mochica Fine Line and Mochica Polychrome were the most similar archaeological groups, at Mochica times, because of the use of the same raw material for production. However, Highland Cajamarca is the most different ceramic group from the other studied ones due to the use of different raw materials from Cajamarca valley located 100 km east of San José de Moro site.
Показать больше [+] Меньше [-]Association between thyroid function and urinary levels of 3,5,6-trichloro-2-pyridinol: data from NHANES 2007–2008 Полный текст
2017
Jain, Ram B.
Data from National Health and Nutrition Examination Survey for the years 2007–2008 were used to evaluate the association between serum levels of thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), free thyroxine (FT4), total triiodothyronine (TT3), total thyroxine (TT4), and thyroglobulin (TGN) with the urinary levels of 3,5,6-trichloro-2-pyridinol (TCPY). Gender-stratified regression models with log10-transformed values of thyroid hormones as dependent variables and TCPY tertiles, age, race/ethnicity, smoking and iodine sufficiency statuses, fasting time, body mass index, and poverty income ratio as independent variables were fitted. TCPY levels were not found to be associated with the levels of TSH, FT3, FT4, and TT3 for either males or females. TCPY levels in the third tertile as compared to first tertile were found to be negatively associated (p ≤ 0.01) with TT4 levels for both males and females. TGN levels for those males who were in third tertile of TCPY were statistically significantly lower (p < 0.01) than for those who had their TCPY levels in first or second tertile. Irrespective of age, gender, race/ethnicity, and smoking status, unadjusted TCPY levels for the period 2009–2010 were statistically significantly lower (p < 0.01) than TCPY levels during the period 2001–2002. TCPY levels for 2009–2010 were as low as 35.8% of what they were in 2001–2002 for adolescents and not more than 56.9% of what they were for 2001–2002 for males.
Показать больше [+] Меньше [-]Particle size distribution of inorganic and organic ions in coastal and inland Antarctic aerosol Полный текст
2017
Barbaro, Elena | Padoan, Sara | Kirchgeorg, Torben | Zangrando, Roberta | Toscano, Giuseppa | Barbante, Carlo | Gambaro, Andrea
The concentration and particle-size distribution of ionic species in Antarctic aerosol samples were determined to investigate their potential sources, chemical evolution, and transport. We analyzed aerosol samples collected at two different Antarctic sites: a coastal site near Victoria Land close to the Italian Research Base “Mario Zucchelli”, and another site located on the Antarctic plateau, close to Italian-French Concordia Research Station. We investigated anionic compounds using ion-chromatography coupled to mass spectrometry, and cationic species through capillary ion chromatography with conductometry. Aerosol collected close to the coast was mainly characterized by sea salt species such as Na⁺, Mg²⁺, and SO₄ ²⁻. These species represented a percentage of 88% of the total sum of all detected ionic species in the aerosol samples from the coastal site. These species were mainly distributed in the coarse fraction, confirming the presence of primary aerosol near the ocean source. Aerosol collected over the Antarctic plateau was characterized by high acidity, with nss-SO₄ ²⁻, NO₃ ⁻, and methanesulfonic acid as the most abundant species. These species were mainly distributed in the <0.49 μm fraction, and they had a behavior of a typical secondary aerosol, where several chemical and physical processes occurred.
Показать больше [+] Меньше [-]Assessment of uptake and phytotoxicity of cyanobacterial extracts containing microcystins or cylindrospermopsin on parsley (Petroselinum crispum L.) and coriander (Coriandrum sativum L) Полный текст
2017
Pereira, Ana L. | Azevedo, Joana | Vasconcelos, Vitor
Assessment of uptake and phytotoxicity of cyanobacterial extracts containing microcystins or cylindrospermopsin on parsley (Petroselinum crispum L.) and coriander (Coriandrum sativum L) Полный текст
2017
Pereira, Ana L. | Azevedo, Joana | Vasconcelos, Vitor
Blooms of harmful cyanobacteria that synthesize cyanotoxins are increasing worldwide. Agronomic plants can uptake these cyanotoxins and given that plants are ultimately ingested by humans, this represents a public health problem. In this research, parsley and coriander grown in soil and watered through 7 days with crude extracts containing microcystins (MCs) or cylindrospermopsin (CYN) in 0.1–1 μg mL⁻¹ concentration range were evaluated concerning their biomass, biochemical parameters and uptake of cyanotoxins. Although biomass, chlorophylls (a and b), carotenoids and glutathione-S-transferase of parsley and coriander exposed to the crude extracts containing MC or CYN had shown variations, these values were not statistically significantly different. Protein synthesis is not inhibited in coriander exposed to MC or CYN and in parsley exposed to MC. Also, glutathione reductase (GR) and glutathione peroxidase (GPx) in parsley and coriander was not affected by exposure to MC, and in coriander, the CYN did not induce statistically significant differences in these two antioxidative enzymes. Only parsley showed statistically significant increase in protein content exposed to 0.5 μg CYN mL⁻¹ (3.981 ± 0.099 mg g⁻¹ FW) compared to control (2.484 ± 0.145 mg g⁻¹ FW), statistically significant decrease in GR exposed to 0.1 μg CYN mL⁻¹ (0.684 ± 0.117 nmol min⁻¹ mg⁻¹ protein) compared to control (1.30 ± 0.06 nmol min⁻¹ mg⁻¹ protein) and statistically significant increase in GPx exposed to 1 μg CYN mL⁻¹ (0.054 ± 0.026 nmol min⁻¹ mg⁻¹ protein) compared to 0.5 μg CYN mL⁻¹ (0.003 ± 0.001 nmol min⁻¹ mg⁻¹ protein). These changes may be due to the induction of defensive mechanisms by plants by the presence of toxic compounds in the soil or probably to a low generation of reactive oxygen species. Furthermore, the parsley and coriander leaves and stems after 10 days of exposure did not accumulate microcystins or cylindrospermopsin.
Показать больше [+] Меньше [-]Assessment of uptake and phytotoxicity of cyanobacterial extracts containing microcystins or cylindrospermopsin on parsley (Petroselinum crispum L.) and coriander (Coriandrum sativum L) Полный текст
2017
Pereira A.L. | Azevedo J. | Vasconcelos V. | CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental
Blooms of harmful cyanobacteria that synthesize cyanotoxins are increasing worldwide. Agronomic plants can uptake these cyanotoxins and given that plants are ultimately ingested by humans, this represents a public health problem. In this research, parsley and coriander grown in soil and watered through 7 days with crude extracts containing microcystins (MCs) or cylindrospermopsin (CYN) in 0.1–1 μg mL−1 concentration range were evaluated concerning their biomass, biochemical parameters and uptake of cyanotoxins. Although biomass, chlorophylls (a and b), carotenoids and glutathione-S-transferase of parsley and coriander exposed to the crude extracts containing MC or CYN had shown variations, these values were not statistically significantly different. Protein synthesis is not inhibited in coriander exposed to MC or CYN and in parsley exposed to MC. Also, glutathione reductase (GR) and glutathione peroxidase (GPx) in parsley and coriander was not affected by exposure to MC, and in coriander, the CYN did not induce statistically significant differences in these two antioxidative enzymes. Only parsley showed statistically significant increase in protein content exposed to 0.5 μg CYN mL−1 (3.981 ± 0.099 mg g−1 FW) compared to control (2.484 ± 0.145 mg g−1 FW), statistically significant decrease in GR exposed to 0.1 μg CYN mL−1 (0.684 ± 0.117 nmol min−1 mg−1 protein) compared to control (1.30 ± 0.06 nmol min−1 mg−1 protein) and statistically significant increase in GPx exposed to 1 μg CYN mL−1 (0.054 ± 0.026 nmol min−1 mg−1 protein) compared to 0.5 μg CYN mL−1 (0.003 ± 0.001 nmol min−1 mg−1 protein). These changes may be due to the induction of defensive mechanisms by plants by the presence of toxic compounds in the soil or probably to a low generation of reactive oxygen species. Furthermore, the parsley and coriander leaves and stems after 10 days of exposure did not accumulate microcystins or cylindrospermopsin. © 2016, Springer-Verlag Berlin Heidelberg. | European Social Funding (FSE) under the Human Potential Operational Program (POPH) of National Strategic Reference Board (QREN) supports the fellowship SFRH/BPD/44459/2008 to Ana L. Pereira. This research was partially supported by the Strategic Funding UID/Multi/04423/2013 through national funds provided by FCT—Foundation for Science and Technology and European Regional Development Fund (ERDF), in the framework of the program PT2020. Thanks are given to Benedita Monteiro and Catarina Santos for the growth, extraction and quantification of microcystins from M. aeruginosa and cylindrospermopsin from A. ovalisporum respectively.
Показать больше [+] Меньше [-]Do estrogenic compounds in drinking water migrating from plastic pipe distribution system pose adverse effects to human? An analysis of scientific literature Полный текст
2017
Liu, Ze-hua | Yin, Hua | Dang, Zhi
With the widespread application of plastic pipes in drinking water distribution system, the effects of various leachable organic chemicals have been investigated and their occurrence in drinking water supplies is monitored. Most studies focus on the odor problems these substances may cause. This study investigates the potential endocrine disrupting effects of the migrating compound 2,4-di-tert-butylphenol (2,4-d-t-BP). The summarized results show that the migration of 2,4-d-t-BP from plastic pipes could result in chronic exposure and the migration levels varied greatly among different plastic pipe materials and manufacturing brands. Based on estrogen equivalent (EEQ), the migrating levels of the leachable compound 2,4-d-t-BP in most plastic pipes were relative low. However, the EEQ levels in drinking water migrating from four out of 15 pipes may pose significant adverse effects. With the increasingly strict requirements on regulation of drinking water quality, these results indicate that some drinking water transported with plastic pipes may not be safe for human consumption due to the occurrence of 2,4-d-t-BP. Moreover, 2,4-d-t-BP is not the only plastic pipe-migrating estrogenic compound, other compounds such as 2-tert-butylphenol (2-t-BP), 4-tert-butylphenol (4-t-BP), and others may also be leachable from plastic pipes.
Показать больше [+] Меньше [-]Effects of a controlled freeze-thaw event on dissolved and colloidal soil organic matter Полный текст
2017
Kim, Eun-Ah | Lee, Ha Kyung | Choi, Jung Hyun
This study investigated the effects of the freezing and thawing that accompany the warming process on the composition of the soil organic matter in the dissolved and colloidal fractions. Temperate soil samples were incubated in a refrigerator at 2 °C for 4 weeks and compared with those frozen at −20 °C in the second week followed by thawing at 2 °C to study a freeze-thaw effect with minimal effect from the thawing temperature. The freeze-thaw group was compared with those incubated at 25 °C in the last week to investigate a warming effect after thawing. Thawing at 2 °C after freezing at −20 °C increased the dissolved organic carbon (DOC), but decreased colloidal Ca. The subsequent warming condition greatly increased both DOC and colloidal Ca. The colloidal organic carbon (COC) and dissolved Ca showed rather subtle changes in response to the freeze-thaw and warming treatments compared to the changes in DOC and colloidal Ca. The fluorescence excitation-emission matrix (EEM) and Fourier transformation-infrared spectrometry (FT-IR) results showed that the freeze-thaw and warming treatments gave the opposite effects on the compositions of dissolved humic-like substances, polysaccharides or silicates, and aliphatic alcohols. A principal component analysis (PCA) with the DOC, fluorescence EEM, and FT-IR spectra produced two principal components that successfully distinguished the effects of the freeze-thaw and warming treatments. Due to the contrasting effects of the freeze-thaw and warming treatments, the overall effects of freeze-thaw events in nature on the dissolved and colloidal soil organic matter could vary depending on the thawing temperature.
Показать больше [+] Меньше [-]Mercury release during thermal treatment of two Chinese coal gangues Полный текст
2017
Guo, Shaoqing | Niu, Xiangrui | Zhai, Jindong
The utilization of coal gangue in power plants has become a new anthropogenic discharge source of mercury and attracted much concern in China. It is crucial to obtain the information about the mercury release during thermal treatment of coal gangue. In this study, the mercury release behavior of two coal gangues selected from two power plants were studied under different thermal treatment conditions of heating rate, residence time, and atmosphere. The results of mercury release profile show that the specified release temperature ranges for the different modes of occurrence of Hg are scarcely affected by the heating rate of 10, 20, and 40 °C/min. A higher heating rate could promote the Hg release to some extent. The mercury release ratio gradually increases with the extension of residence time for both coal gangues. The oxidizing environment has a positive effect on mercury release < 600 °C and has a minor effect > 600 °C. Mercury in coal gangue is more volatile than coal gangue matrix and the mercury in GD coal gangue is more easily released out than that in ED coal gangue.
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