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1.
Chemosphere ; : 142433, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38815812

RESUMEN

Pesticides are becoming more prevalent in agriculture to protect crops and increase crop yields. However, nearly all pesticides used for this purpose reach non-target crops and remain as residues for extended periods. Contamination of soil by widespread pesticide use, as well as its toxicity to humans and other living organisms, is a global concern. This has prompted us to find solutions and develop alternative remediation technologies for sustainable management. This article reviews recent technological developments for remediating pesticides from contaminated soil, focusing on the following major points: (1) The application of various pesticide types and their properties, the sources of pesticides related to soil pollution, their transport and distribution, their fate, the impact on soil and human health, and the extrinsic and intrinsic factors that affect the remediation process are the main points of focus. (2) Sustainable pesticide degradation mechanisms and various emerging nano- and bioelectrochemical soil remediation technologies. (3) The feasible and long-term sustainable research and development approaches that are required for on-site pesticide removal from soils, as well as prospects for applying them directly in agricultural fields. In this critical analysis, we found that bioremediation technology has the potential for up to 90% pesticide removal from the soil. The complete removal of pesticides through a single biological treatment approach is still a challenging task; however, the combination of electrochemical oxidation and bioelectrochemical system approaches can achieve the complete removal of pesticides from soil. Further research is required to remove pesticides directly from soils in agricultural fields on a large scale.

2.
Front Plant Sci ; 14: 1151786, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37063213

RESUMEN

Introduction: The increasing use of cerium nanoparticles (CeO2-NPs) has made their influx in agroecosystems imminent through air and soil deposition or untreated wastewater irrigation. Another major pollutant associated with anthropogenic activities is Cd, which has adverse effects on plants, animals, and humans. The major source of the influx of Cd and Ce metals in the human food chain is contaminated food, making it an alarming issue; thus, there is a need to understand the factors that can reduce the potential damage of these heavy metals. Methods: The present investigation was conducted to evaluate the effect of CeO2-10-nm-NPs and Cd (alone and in combination) on Zea mays growth. A pot experiment (in sand) was conducted to check the effect of 0, 200, 400, 600, 1,000, and 2,000 mg of CeO2-10 nm-NPs/kg-1 dry sand alone and in combination with 0 and 0.5 mg Cd/kg-1 dry sand on maize seedlings grown in a partially controlled greenhouse environment, making a total of 12 treatments applied in four replicates under a factorial design. Maize seedling biomass, shoot and root growth, nutrient content, and root anatomy were measured. Results and discussion: The NPs were toxic to plant biomass (shoot and root dry weight), and growth at 2,000 ppm was the most toxic in Cd-0 sets. For Cd-0.5 sets, NPs applied at 1,000 ppm somewhat reverted Cd toxicity compared with the contaminated control (CC). Additionally, CeO2-NPs affected Cd translocation, and variable Ce uptake was observed in the presence of Cd compared with non-Cd applied sets. Furthermore, CeO2-NPs partially controlled the elemental content of roots and shoots (micronutrients such as B, Mn, Ni, Cu, Zn, Mo, and Fe and the elements Co and Si) and affected root anatomy.

3.
Environ Pollut ; 309: 119769, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-35850318

RESUMEN

The present experiment was conducted to appraise the role of different seed priming agents in circumventing the negative impact of chromium (Cr) toxicity on canola plants. Chromium toxicity resulted in significant decline in photosynthetic pigments and growth attributes of two canola cultivars (Puriga and MS-007). Cr toxicity also resulted in higher oxidative stress mirrored as greater accumulation of hydrogen peroxide (H2O2) superoxide radical (O2•‒), electrolyte leakage (EL) and malondialdehyde (MDA). Further, lipoxygenase enzyme activity that catalyzes the peroxidation of membrane lipids was also enhanced due to Cr toxicity. Canola plants also manifested impaired methylglyoxal (MG) detoxification due to the downregulation of glyoxalase enzymes (GlyI and II) under Cr stress. Seed priming treatments viz. osmo-priming with calcium chloride (CaCl2) and hormonal priming with salicylic acid (SA) remarkably improved growth and chlorophyll content in both canola cultivars under Cr toxicity as compared to other priming treatments such as hydro-priming, redox priming (H2O2) and chemical priming (Se; selenium). Moreover, CaCl2 and SA seed priming also resulted in lower oxidative stress and improved enzymatic (SOD, POD, CAT, APX, GR, GST) and non-enzymatic (GSH, phenolics, flavonoids, proline) antioxidant system of both cultivars under Cr toxicity. Further, hormonal and osmo-priming strengthened glyoxalase and antioxidant systems, thus improving reactive oxygen species (ROS) and MG detoxification. In this background, the cultivar Puriga is considered Cr tolerant as it exhibited better growth and lesser oxidative stress in both seed priming and non-primed conditions under Cr toxicity than cv. MS-007.


Asunto(s)
Brassica napus , Selenio , Antioxidantes/metabolismo , Cloruro de Calcio , Cromo , Peróxido de Hidrógeno/farmacología , Oxidación-Reducción , Estrés Oxidativo , Semillas/metabolismo , Selenio/farmacología
4.
Environ Sci Pollut Res Int ; 29(51): 77321-77332, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35672649

RESUMEN

The effects of foliar supply of silicon nanoparticles (Si-NPs) on growth, physiology, and cadmium (Cd) uptake by wheat (Triticum aestivum L.) were examined in different soil moisture levels. Seeds were sown in soil containing excess Cd (7.67 mg kg-1) and Si-NPs were applied through foliar dressing with various levels (0, 25, 50, 100 mg L-1) at different time intervals during growth period. Initially, all pots were irrigated with normal moisture level (70% water-holding capacity) and two moisture levels (35%, 70% WHC) were initiated after 6 weeks of plant growth for remaining growth duration and harvesting was done after 124 days of sowing. The results demonstrated the lowest plant growth, yield, and chlorophyll concentrations while the highest oxidative stress and Cd concentrations in plant tissues in water-stressed control (35% WHC) followed by normal control (75% WHC). Si-NPs enhanced the growth, photosynthesis, leaf defense system, and Si concentrations in tissues while minimized the Cd in wheat parts particularly in grains either soil normal or water-stressed conditions. Of the foliar spray, 100 mg L-1 of Si-NPs showed the best results with respect to growth, Cd and Si uptake by plants, and soil post-harvest bioavailable Cd irrespective of soil water levels. In grain, Cd concentration was below threshold limit (0.2 mg kg-1) for cereals in 100-mg kg-1 Si-NPs treatment irrespective of soil water levels. Si-NPs foliar dressing under Cd and water-limited stress might be an effective strategy in increasing growth, yield, and decreasing Cd concentration in wheat grains under experimental conditions. Thus, foliar dressing of Si-NPs minimized the Cd risk in food crops and NPs entry to surroundings, which might be possible after harvesting of crops in soil-applied NPs.


Asunto(s)
Nanopartículas , Contaminantes del Suelo , Cadmio/análisis , Triticum , Silicio/farmacología , Contaminantes del Suelo/análisis , Suelo , Clorofila/farmacología , Grano Comestible/química , Agua
5.
Sensors (Basel) ; 22(3)2022 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-35161958

RESUMEN

Recent technological developments pave the path for deep learning-based techniques to be used in almost every domain of life. The precision of deep learning techniques make it possible for these to be used in the medical field for the classification and detection of various diseases. Recently, the coronavirus (COVID-19) pandemic has put a lot of pressure on the health system all around the world. The diagnosis of COVID-19 is possible by PCR testing and medical imagining. Since COVID-19 is highly contagious, diagnosis using chest X-ray is considered safe in various situations. In this study, a deep learning-based technique is proposed to classify COVID-19 infection from other non-COVID-19 infections. To classify COVID-19, three different pre-trained models named EfficientNetB1, NasNetMobile and MobileNetV2 are used. The augmented dataset is used for training deep learning models while two different training strategies have been used for classification. In this study, not only are the deep learning model fine-tuned but also the hyperparameters are fine-tuned, which significantly improves the performance of the fine-tuned deep learning models. Moreover, the classification head is regularized to improve the performance. For the evaluation of the proposed techniques, several performance parameters are used to gauge the performance. EfficientNetB1 with regularized classification head outperforms the other models. The proposed technique successfully classifies four classes that include COVID-19, viral pneumonia, lung opacity, and normal, with an accuracy of 96.13%. The proposed technique shows superiority in terms of accuracy when compared with recent techniques present in the literature.


Asunto(s)
COVID-19 , Aprendizaje Profundo , Algoritmos , Humanos , Redes Neurales de la Computación , SARS-CoV-2 , Rayos X
6.
Ecotoxicol Environ Saf ; 221: 112437, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34153540

RESUMEN

Agricultural soils are receiving higher inputs of trace elements (TEs) from anthropogenic activities. Application of nanoparticles (NPs) in agriculture as nano-pesticides and nano-fertilizers has gained rapid momentum worldwide. The NPs-based fertilizers can facilitate controlled-release of nutrients which may be absorbed by plants more efficiently than conventional fertilizers. Due to their large surface area with high sorption capacity, NPs can be used to reduce excess TEs uptake by plants. The present review summarizes the effects of NPs on plant growth, photosynthesis, mineral nutrients uptake and TEs concentrations. It also highlights the possible mechanisms underlying NPs-mediated reduction of TEs toxicity at the soil and plant interphase. Nanoparticles are effective in immobilization of TEs in soil through alteration of their speciation and improving soil physical, chemical, and biological properties. At the plant level, NPs reduce TEs translocation from roots to shoots by promoting structural alterations, modifying gene expression, and improving antioxidant defense systems. However, the mechanisms underlying NPs-mediated TEs uptake and toxicity reduction vary with NPs type, mode of application, time of NPs exposure, and plant conditions (e.g., species, cultivars, and growth rate). The review emphasizes that NPs may provide new perspectives to resolve the problem of TEs toxicity in crop plants which may also reduce the food security risks. However, the potential of NPs in metal-contaminated soils is only just starting to be realized, and additional studies are required to explore the mechanisms of NPs-mediated TEs immobilization in soil and uptake by plants. Such future knowledge gap has been highlighted and discussed.


Asunto(s)
Nanopartículas , Plantas/efectos de los fármacos , Oligoelementos/metabolismo , Oligoelementos/toxicidad , Agricultura , Metales/metabolismo , Metales/toxicidad , Raíces de Plantas/metabolismo , Plantas/metabolismo , Suelo/química , Contaminantes del Suelo/metabolismo , Contaminantes del Suelo/toxicidad
7.
Ecotoxicol Environ Saf ; 215: 112148, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33756292

RESUMEN

Low use efficiency of nitrogen (N) and phosphorus (P) is major challenge of modern agriculture. Coating of conventional fertilizers with nanomaterials is a promising technique for improved nutrient use efficiency. In current study, nanoparticles (NPs) of potassium ferrite (KFeO2 NPs) were coated on di-ammonium phosphate (DAP) fertilizer with three rates (2, 5, 10%) of KFeO2 NPs and were evaluated for release of N, P, K and Fe supplementation in clay loam and loam soil up to 60 days. The NPs were characterized for crystal assemblage, bond formation, morphology and configuration using the x-ray diffraction (XRD), scanning electron microscope (SEM) and Fourier transform-infra red spectroscopy (FT-IR). The results showed that size of NPs ranged between 7 and 18 nm. The controlled release of P in 10% KFeO2 nano-coated DAP was observed throughout the incubation period. The P release kept on increasing from day-1 (14.5 µg g-1) to day-60 (178.6 µg g-1) in coated DAP (10%) in loam soil. The maximum release of 50.4 µg g-1 NH4+1-N in coated DAP (10%) was observed after 30 days of incubation. The release of NO3-1-N was consistent up to 45 and 60 days in clay loam and loam soil, respectively. The average release of potassium and iron in 60 days was 19.7 µg g-1 and 7.3 µg g-1 higher in 10% coated DAP than traditional DAP in clay loam soil. It was concluded that KFeO2 nano-coated DAP supplied P and mineral N for longer period of time in both soils, and some higher coating levels should be tested in future.


Asunto(s)
Fertilizantes/análisis , Nanopartículas/química , Fosfatos/química , Potasio , Agricultura , Arcilla , Compuestos Férricos , Nitrógeno , Nutrientes , Fósforo/química , Suelo/química , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
8.
Ecotoxicol Environ Saf ; 215: 112139, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33761378

RESUMEN

Cadmium (Cd) accumulation in arable lands has become a serious matter for food security. Among various approaches, the application of nanoparticles (NPs) for remediation of contaminated water and soils is attaining more popularity worldwide. The current field experiment was executed to explore the impacts of single and combined use of ZnO NPs, Fe NPs and Si NPs on wheat growth and Cd intake by plants in a Cd-contaminated field. Wheat was sown in a field which was contaminated with Cd and was irrigated with the raw-city-effluent while NPs were applied as foliar spray alone and in all possible combinations. The data revealed that straw and grain yields were enhanced in the presence of NPs over control. Chlorophyll, carotenoids contents and antioxidants activities were enhanced while electrolyte leakage was reduced with all NPs over control. In comparison with control, Cd uptake in wheat straw was reduced by 84% and Cd uptake in grain was reduced by 99% in T8 where all three NPs were foliar-applied simultaneously. Zinc (Zn) and iron (Fe) contents were increased in those plants where ZnO and Fe NPs were exogenously applied which revealed that ZnO and Fe NPs enhanced the bio-fortification of Zn and Fe in wheat grains. Overall, foliar application of different NPs is beneficial for better wheat growth, yield, nutrients uptake and to lessen the Cd intake by plants grown in Cd-contaminated soil under real field conditions.


Asunto(s)
Cadmio/metabolismo , Nanopartículas/química , Contaminantes del Suelo/metabolismo , Triticum/fisiología , Antioxidantes , Cadmio/análisis , Cadmio/toxicidad , Clorofila , Grano Comestible/química , Contaminación Ambiental , Hojas de la Planta/química , Suelo , Contaminantes del Suelo/análisis , Contaminantes del Suelo/toxicidad , Triticum/crecimiento & desarrollo , Zinc/análisis , Óxido de Zinc
9.
J Hazard Mater ; 415: 125585, 2021 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-33721774

RESUMEN

A field study was designed to explore the impacts of foliar-applied chemically and green synthesized titanium dioxide nanoparticles (TiO2 NPs) on cadmium (Cd) uptake in wheat plants. The wheat was grown in field which was contaminated with Cd and plants were subjected to foliar episodes of TiO2 NPs during plant growth period. Leaf extracts of two plant species (Trianthema portulacastrum, Chenopodium quinoa) were used for green synthesis while sol-gel method was used for chemical preparation of TiO2 NPs. Results showed that TiO2 NPs significantly enhanced the plant height, length of spikes photosynthesis, and straw and grain yield compared to control. TiO2 NPs minimized the oxidative burst in leaves and improved the enzyme activities than control. Cadmium concentrations of straw, roots and grains decreased after TiO2 NPs treatments than control. The grain Cd contents were below recommended threshold (0.2 mg Cd /kg grain DW) for cereals upon NPs exposure. The health risk index by the dietary use of grains for adults was below threshold upon NPs exposure. Overall, foliar use of TiO2 NPs prepared from plant extracts was appropriate in minimizing Cd contents in wheat grains, thereby reducing risk of Cd to human health via food chain.


Asunto(s)
Nanopartículas , Contaminantes del Suelo , Cadmio/análisis , Cadmio/toxicidad , Humanos , Suelo , Contaminantes del Suelo/análisis , Titanio , Triticum
10.
Ecotoxicol Environ Saf ; 212: 111978, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33561774

RESUMEN

Nanotechnology is capturing great interest worldwide due to their stirring applications in various fields. Among nanoparticles (NPs), titanium dioxide (TiO2) NPs have been widely used in daily life and can be synthesized through various physical, chemical, and green methods. Green synthesis is a non-toxic, cost-effective, and eco-friendly route for the synthesis of NPs. Plenty of work has been reported on the green, chemical, physical and biological synthesis of TiO2 NPs and these NPs can be characterized through high tech. instruments. In the present review, dense data have been presented on the comparative synthesis of TiO2 NPs with different characteristics and their wide range of applications. Among the TiO2 NPs synthesis techniques, the green methods have been proven to be efficient than chemical synthesis methods because of the less use of precursors, time-effectiveness, and energy-efficiency during the green synthesis procedures. Moreover, this review describes the types of plants (shrubs, herbs and trees), microorganisms (bacteria, fungi and algae), biological derivatives (proteins, peptides, and starches) employed for the synthesis of TiO2 NPs. The TiO2 NPs can be effectively used for the treatment of polluted water and positively affected the plant physiology especially under abiotic stresses but the response varied with types, size, shapes, doses, duration of exposure, metal species along with other factors. This review also highlights the regulating features and future standpoints for the measurable enrichment in TiO2 NPs product and perspectives of TiO2 NPs reliable application.


Asunto(s)
Nanopartículas , Titanio , Nanopartículas del Metal/química , Extractos Vegetales , Plantas/química
11.
Chemosphere ; 266: 128980, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33243575

RESUMEN

Phosphorous (P) fixation in alkaline calcareous soils is a serious concern worldwide and acidified-biochar application has been proposed to improve the agronomic benefits of applied P. The present study aims to improve understanding of P transformation process in an alkaline soil following different biochar amendments (rice-husk biochar (RHB), sugarcane-bagasse biochar (SWB) and wheat-straw biochar (WSB)), chemically engineered (acidification with 1 N HCl or washing with distilled water (pristine biochar)) along with or without P at 60 mg kg-1. A pot experiment was conducted with three biochars (RHB, SWB, WSB) and control, two chemical modifications (acidic and pristine), and two P-levels (without or with P). A pot study by growing spring maize and a parallel incubation study were done to test the treatment effects on P transformation. Results demonstrated that acidified SBC and WSB increased the plant P uptake and dry-matter yield by 40% and 29.7%, respectively, with P-supply. Both pristine or acidified RHB produced 80.5% and 110.7%, more root dry-matter, respectively, compared to respective controls without P. Non-acidified WSB along with P showed significantly higher Olson's P in incubation study. While in case of acidification along with P addition, RHB exhibited greater P availability, but it was inconsistent at different times during incubation. It can be concluded that acidified biochar amendments have potential to improve P management with inconsistent results. It is difficult to rule out that acidification of biochars is a pre-requisite for alkaline soils for P improvement. Further research is needed to explore site-specific P management for sustainable crop production.


Asunto(s)
Contaminantes del Suelo , Suelo , Disponibilidad Biológica , Carbón Orgánico , Fósforo , Contaminantes del Suelo/análisis , Zea mays
12.
Water Sci Technol ; 81(3): 466-478, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32385200

RESUMEN

Amine functionalized carbon (AFC) was synthesized from raw oil fly ash and later utilized it for simultaneous removal of methyl orange (MO) and rhodamine 6G (Rh6G) pollutant dyes from aqueous medium. AFC was analyzed through scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) surface area and Fourier transform infrared spectroscopy (FTIR) to examine its morphology, porosity and structural characteristics, respectively. The effect of various process parameters like mixing time, pollutant concentration, adsorbent dose, initial solution pH, and temperature of the medium were investigated for dye removal process. The experimental findings showed that the percentage removal of Rh6G was higher than MO and both dyes showed synergism during the adsorption from binary dye solution. Pseudo-second-order model was most appropriate model for both dyes and thermodynamic parameters showed that the dyes removal process was endothermic in nature. Among various isotherm models, Hill and Toth isotherms best explain the adsorption of Rh6G and MO from binary dye solution.


Asunto(s)
Colorantes , Contaminantes Químicos del Agua , Adsorción , Aminas , Carbono , Concentración de Iones de Hidrógeno , Cinética , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica , Agua
13.
Environ Sci Pollut Res Int ; 27(19): 23926-23936, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32301070

RESUMEN

Cadmium (Cd) availability in arable soils is a serious issue while little is known about the role of co-composted organic amendments and zinc oxide nanoparticles (ZnO-NPs) foliar spray on biomass and Cd accumulation in wheat grains. The current study investigated the soil application of organic amendment (composted biochar and farmyard manure) at a level of 0, 1, and 2% w/w and foliar spray of ZnO-NPs (0, 100, and 200 mg/L) on biomass, yield, and Cd in wheat grains cultivated in an aged Cd-contaminated agricultural soil. The results indicated that organic amendment increased the biomass, chlorophyll concentrations, yield, and activities of peroxidase and superoxide dismutase of wheat while decreased the electrolyte leakage and Cd concentrations in different parts of wheat such as shoots, roots, husks, and grains. This effect of organic amendment was further enhanced by the foliar spray of ZnO-NPs in a dose-additive manner. Cadmium concentration in grains was below threshold level (0.2 mg/kg DW) for cereals in combined application of 200 mg/L ZnO-NPs and 1% organic amendment as well as in higher treatment (2%) of organic amendment and NPs. Thus, combined use of organic materials and NPs might be a suitable way of reducing Cd and probably other toxic trace element concentrations in wheat and other cereals.


Asunto(s)
Nanopartículas , Contaminantes del Suelo/análisis , Óxido de Zinc , Cadmio/análisis , Suelo , Triticum
14.
Chemosphere ; 244: 125548, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32050343

RESUMEN

Wheat (Triticum aestivum L.) cultivation in cadmium (Cd) polluted soil is a core concern to food quality and food security all over the world. Cadmium toxicity is mainly associated with a Cd influx from contaminated soils to human via grain consumption. Organic amendments are widely used for Cd immobilization and enhancement in plant growth, but the residual effects of these amendments are mostly unknown. The present study addressed the long-term effects of organic amendments in contaminated soils by evaluating their residual effects on 3rd crop (wheat) in the sequence. Initially six organic amendments viz. rice husk biochar (RHB), wheat-straw biochar (WSB), cotton-stick biochar (CSB), poultry manure (PM), press mud (PrMd) and farm manure (FM) were applied once at a rate of 2% in Cd (50 mg kg-1) contaminated soil with wheat-rice rotation. After the harvest of wheat and rice crops, wheat (Var. Galaxy) was again grown in the same pots. Results revealed that plants grown under Cd stress (without any amendment) contain more tissue (root, shoot and grain) and soil AB-DTPA extractable Cd. The soil amended with RHB has shown lowest AB-DTPA extractable Cd (69% lower than control). Similarly, RHB application has significantly reduced wheat root, shoot and grain Cd concentrations compared to control and other amendments. Results have confirmed the effectiveness of RHB residual contents as an active amendment for restriction of Cd in non-bioavailable pool of soil and better growth and yield of wheat.


Asunto(s)
Cadmio/metabolismo , Contaminantes del Suelo/metabolismo , Triticum/metabolismo , Disponibilidad Biológica , Cadmio/análisis , Carbón Orgánico , Productos Agrícolas , Grano Comestible/química , Estiércol , Oryza/crecimiento & desarrollo , Suelo , Contaminantes del Suelo/análisis , Triticum/crecimiento & desarrollo
15.
Environ Sci Pollut Res Int ; 26(18): 18053-18070, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31093913

RESUMEN

The successful phytoextraction of potentially toxic elements (PTEs) from polluted soils can be achieved by growing non-food and industrial crops. Tobacco (Nicotiana tabacum L.) is one of the main industrial crops and is widely grown in many countries. Tobacco can uptake high concentrations of PTEs especially in aboveground biomass without suffering from toxicity. This review highlighted the potential of tobacco for the phytoextraction of heavy metals and tolerance mechanisms under metal stress. Different management practices have been discussed which can enhance the potential of this plant for metal extraction. Finally, suitable options for the management/disposal of biomass enriched in excess metal have been elaborated to prevent secondary pollution.


Asunto(s)
Metales Pesados/análisis , Nicotiana/crecimiento & desarrollo , Contaminantes del Suelo/análisis , Suelo/química , Biodegradación Ambiental , Biomasa , Metales Pesados/metabolismo , Estrés Oxidativo/efectos de los fármacos , Contaminantes del Suelo/metabolismo , Nicotiana/efectos de los fármacos , Nicotiana/metabolismo
16.
Chemosphere ; 226: 454-462, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30951940

RESUMEN

Food contamination with cadmium (Cd) is a serious health threat to humans worldwide and Cd accumulation by rice is a major source of Cd entrance to the food chain. Silicon (Si) application decreases the Cd content in rice but the timing of Si application may need further investigation. The present study investigated the effect of split application of Si in the soil (600 kg/ha of Si) at different growth stages of rice on the growth and Cd accumulation by rice under Cd stress. Rice plants were grown in the presence and absence of Cd and Si was applied in the soil at different growth stages of rice under Cd stress. The results indicated that Cd stress alone reduced the growth and photosynthesis and increased the Cd content in different tissues and grains of rice. Silicon application improved the plant growth and reduced the Cd accumulation, translocation factor, and bioaccumulation factor in rice especially in grains, whereas the response of Si varied with the application of Si at different growth stages. The application of Si in three splits (transplanting (S1), tillering (S2), panicle initiation (S3)) was the best in improving growth and reducing Cd concentrations in plants compared to other combinations of Si application. Silicon application in three splits (S1+S2+S3) reduced the grain Cd concentrations below the threshold level (0.2 mg/kg) and reduced the Cd health risk index under the experimental conditions. Overall, split application of Si at three growth stages may function as remediator and diminishes Cd uptake into rice grains.


Asunto(s)
Cadmio/química , Oryza/química , Silicio/química , Contaminantes del Suelo/química , Suelo/química , Fotosíntesis
17.
Ecotoxicol Environ Saf ; 173: 156-164, 2019 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-30771659

RESUMEN

The present study demonstrated the possible impacts of iron oxide nanoparticles (Fe NPs) on the alleviation of toxic effects of cadmium (Cd) in wheat and enhance its growth, yield, and Fe biofortification. A pot experiment was conducted in historically Cd-contaminated soil using five levels of Fe NPs (0, 5, 10, 15, and 20 ppm) by soil and foliar application methods. The plants were harvested after 125 days of growth while vegetative parameters, antioxidant capacity, electrolyte leakage (EL) in leaves as well as Cd, and Fe concentrations in wheat grains, roots, and shoots were measured. The results showed that the application of Fe NPs mitigated the Cd toxicity on wheat growth and yield parameters. The exogenous application of Fe NPs enhanced the wheat morphological parameters, photosynthetic pigments, and dry biomass of shoots, roots, spike husks and grains. The activities of super oxide dismutase and peroxidase increased, whereas EL reduced from wheat leaves over control. The Cd concentrations were reduced in wheat tissues and grains whereas Fe concentrations increased with Fe NPs application in a dose-additive manner. The current work suggested that the application of Fe NPs on wheat in Cd-contaminated soils could be employed to improve growth, yield and Fe biofortification as well as reduction in Cd concentrations in plants.


Asunto(s)
Cadmio/toxicidad , Compuestos Férricos/farmacología , Nanopartículas , Contaminantes del Suelo/toxicidad , Triticum/efectos de los fármacos , Antioxidantes/metabolismo , Biomasa , Cadmio/metabolismo , Clorofila/metabolismo , Compuestos Férricos/química , Compuestos Férricos/metabolismo , Nanopartículas/química , Nanopartículas/metabolismo , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/metabolismo , Suelo , Contaminantes del Suelo/metabolismo , Triticum/crecimiento & desarrollo , Triticum/metabolismo
18.
Environ Sci Pollut Res Int ; 26(7): 6279-6289, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30635881

RESUMEN

Increasing cadmium (Cd) pollution in agricultural soils has raised serious concerns worldwide. Several exogenous substances can be used to mitigate the toxic effects of Cd in plants. Zinc (Zn) is one of the essential plant micronutrients and is involved in several physiological functions in plants. Zn may alleviate Cd toxicity in plants owing to the chemical similarity of Zn with Cd. Published reports demonstrated that Zn can alleviate toxic effects of Cd in plants by increasing plant growth, regulating Cd uptake, increasing photosynthesis, and reducing oxidative stress. Literature demonstrated that the role of Zn on Cd accumulation by plants is very controversial and depends upon several factors including concentrations of Cd and Zn in the medium, exposure duration, plant species and genotypes, and growth conditions. This review highlights the role of Zn in reducing Cd toxicity in plants and provides new insight that proper level of Zn in plants may enhance plant resistance to excess Cd.


Asunto(s)
Cadmio/toxicidad , Plantas/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Zinc/farmacología , Agricultura , Micronutrientes/farmacología , Estrés Oxidativo , Fotosíntesis/efectos de los fármacos , Desarrollo de la Planta/efectos de los fármacos , Suelo
19.
Annu Int Conf IEEE Eng Med Biol Soc ; 2018: 5220-5223, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30441515

RESUMEN

The surface EMG (sEMG) has been used as control source for upper limb prosthetics since decades. Previous studies suggested that intramuscular EMG showed promising results for upper limb prosthetics. This study investigates the strength of combined surface and intramuscular EMG (cEMG) for improved myoelectric control. Five able-bodied subjects and three transradial amputees were evaluated using offline classification error as performance metric. Six surface and intramuscular channels were recorded concurrently from each subject for seven consecutive days and Stacked sparse autoencoders (SSAE) and LDA classifiers were used for classification. As a control source, either sEMG channels were used or combined channels were used with reduced features using PCA. In the within session analysis, cEMG $( 2.21 \pm 1.19${%) outperformed the sEMG ($4.63 \pm 2.07${%) for both able-bodied and amputee subjects using SSAE. For between session analysis, cEMG outperformed the sEMG for both able-bodied and amputee subjects with percentage points difference of 7.93. These results imply cEMG can significantly improve the performance of pattern recognition based myoelectric control scheme for amputee subjects too and further improvement can be made by utilizing SSAE which show improved performance as compared to LDA.


Asunto(s)
Amputados , Miembros Artificiales , Mano , Electromiografía , Humanos , Movimiento
20.
Environ Pollut ; 241: 557-565, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29885626

RESUMEN

Cadmium (Cd)-contamination of agricultural soils has been receiving attention worldwide due to its entry into food crops such as wheat (Triticum aestivum L.). Little is known regarding the use of organic carbon (OC) sources in alleviating Cd toxicity in cereals. The current experiment was aimed to study the effects of different OC sources on the Cd accumulation by wheat. A pot study was conducted to determine the effects of rice husk biochar (RHB), farmyard manure (FYM), and lignite (LT) either alone or in combination on crop growth, Cd bioavailability and health risk assessment. The results proved that the application of OC sources like RHB, FYM, and LT either alone or in combination were highly effective in enhancing the wheat growth and yield as well as in minimizing the phyto-available fraction of Cd and its transfer to edible tissue of wheat. The RHB was the most efficient source in enhancing the plant growth and reducing the Cd concentration in wheat tissues. RHB increased grain yield by 91% and decreased Cd concentration in shoot, roots, grains, and bioavailable fraction of Cd by 67, 69, 62.5, and 74% than control, respectively. The RHB reduced the daily Cd uptake and health risk index in adults in comparison to control. Overall, where un-amended soil resulted in diminished plant productivity, the application of other OC sources also significantly proved their potential to enhance the dry weight and grain yield, suggesting that these OC sources may be used aiming to minimize the Cd concentration in crops. However, there is still a need to explore the potential of different OC sources in combination with other frequently available amendments for their large scale implementation in metal-contaminated soils.


Asunto(s)
Cadmio/metabolismo , Cadmio/toxicidad , Carbón Orgánico/metabolismo , Carbón Mineral , Estiércol , Contaminantes del Suelo/análisis , Triticum/crecimiento & desarrollo , Triticum/metabolismo , Biodegradación Ambiental/efectos de los fármacos , Disponibilidad Biológica , Cadmio/análisis , Cadmio/farmacocinética , Carbón Orgánico/farmacología , Grano Comestible/química , Grano Comestible/crecimiento & desarrollo , Grano Comestible/metabolismo , Triticum/química
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