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1.
J Healthc Eng ; 2023: 6479187, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36814547

RESUMEN

Health digital GIS map provides a great solution for medical geographical distribution to efficiently explore diseases and health services. In Sudan, tuberculosis disease is expanding in different areas, which requires a digital GIS map to collect information about the patients and support medical institutions by geographical distribution based on health services, drug supply, and consumption. This paper developed a health digital GIS map to provide a fair geographical distribution of tuberculosis health centers and control the drug supply according to medical reports. The proposed approach extracts the unfair distribution of medicine, as some centers receive medicine but do not receive patients, while others receive a large number of patients but limited amounts of medicine. The analysis results show that there is a defect in some states representing the distribution of tuberculosis centers. In the Northern State, there are 15 tuberculosis centers distributed over all localities, serving about 84 tuberculosis-infected patients only.


Asunto(s)
Sistemas de Información Geográfica , Tuberculosis , Humanos , Sudán
2.
Sensors (Basel) ; 23(3)2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36772628

RESUMEN

In recent years, the development of wireless technologies has led to fast growth in mobile networks, especially with the rise of 5G New Radio (5G NR). A huge number of base stations (BSs) are mandatory to serve the growth of mobile services, which has led to concerns about the increase in electromagnetic field (EMF) radiation exposure levels. To control the overall power emitted by EMF transmitters, international bodies have set maximum exposure limits. This paper investigates the compliance distances (CDs) of shared sites by a group of Mobile Network Operators (MNO) as multi-operators operating with multi-technology and sharing the same tower. The study investigated the CDs of the most two commonly used types of sharing sites, macro and indoor-Based solution sites (IBS). In addition, the study analyzed the power densities and total exposure ratios for the general public and occupational workers in each sharing scenario. The results showed that, compared with a single MNO, the CD increased by 41% in the case of two MNOs, 73% for three MNOs, and 100% for four MNOs. The EMF site sharing scale-up formula was used to estimate the increase in CDs for N number of MNOs assuming that all MNOs use the same site configuration. In addition, the results showed that 5G has the highest contribution to the total exposure ratio (TER) at the CD in the main direction of the antennae.

3.
Cluster Comput ; 26(1): 575-586, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35602318

RESUMEN

In recent times, energy related issues have become challenging with the increasing size of data centers. Energy related issues problems are becoming more and more serious with the growing size of data centers. Green cloud computing (GCC) becomes a recent computing platform which aimed to handle energy utilization in cloud data centers. Load balancing is generally employed to optimize resource usage, throughput, and delay. Aiming at the reduction of energy utilization at the data centers of GCC, this paper designs an energy efficient resource scheduling using Cultural emperor penguin optimizer (CEPO) algorithm, called EERS-CEPO in GCC environment. The proposed model is aimed to distribute work load amongst several data centers or other resources and thereby avoiding overload of individual resources. The CEPO algorithm is designed based on the fusion of cultural algorithm (CA) and emperor penguin optimizer (EPO), which boosts the exploitation capabilities of EPO algorithm using the CA, shows the novelty of the work. The EERS-CEPO algorithm has derived a fitness function to optimally schedule the resources in data centers, minimize the operational and maintenance cost of the GCC, and thereby decrease the energy utilization and heat generation. To ensure the improvised performance of the EERS-CEPO algorithm, a wide range of experiments is performed and the experimental outcomes highlighted the better performance over the recent state of art techniques.

4.
Chemosphere ; 309(Pt 2): 136681, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36195126

RESUMEN

Globally, contamination of water by dyes and heavy metals (HMs) is a serious environmental and public health problem due to their carcinogenic and mutagenic nature. It is incumbent to treat innocuously before discharge. It is the first time, hexagonal zinc oxide (ZnO) microstructure are being employeed as a membrane in the simultaneous removal of methyl orange (MO) and chromium (Cr (VI)) from the aqueous solution. The surface chemistry of hexagonal ZnO was characterized for morphology, surface functional groups, crystalline nature, and elemental composition by scanning electron microscope (SEM), Fourier transmission infrared spectroscopy (FTIR), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDX). Adsorption capacity and removal efficiency was determined by the laboratory batch adsorption experiments, while nonlinear, linear kinetics and isotherm models were fitted to experimental data to investigate the adsorption process. The results exhibited that the maximum adsorption capacity (qmax) of hexagonal ZnO from the Langmuir isotherm model was 80.39 mg g-1 and 84.10 mg g-1 for MO and Cr (VI) respectively. According to the modeling findings, linear langmuir fitted to the experimental data with R2 0.967 and 0.971 for both MO and Cr (VI) which indicates monolayer physical adsorption of both pollutants has taken place. Whereas, kinetic study showed nonlinear pseudo-second order with R2 0.989 and 0.986 for MO and Cr (VI) model best fitted with the experimental data. The values of thermodynamics parameters Gibbs free energy change ΔG°, heat of enthalpy ΔH° and, heat of entropy ΔS° indicate that spontaneous, endothermic, and irreversible adsorption reactions occurred. Overall, it is concluded from our observations that hexagonal ZnO has the potential to be used as an eco-friendly, cost-effective adsorbent for simultaneous remaoval of both MO and Cr (VI) from water. Findings of the current investigation provide valuable insights for the development of an inexpensive, effective and sustainable filtration method for the treatment of MO and Cr (VI) synergistically.


Asunto(s)
Restauración y Remediación Ambiental , Contaminantes Químicos del Agua , Óxido de Zinc , Aguas Residuales , Contaminantes Químicos del Agua/análisis , Concentración de Iones de Hidrógeno , Cromo/análisis , Cinética , Adsorción , Termodinámica , Colorantes , Agua
5.
Environ Sci Pollut Res Int ; 29(54): 81337-81350, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35732887

RESUMEN

Urbanization is the main force of the global environmental as well as land use land cover changes (LULC). Urbanization is caused by prompt increase in population growth, migration, and urge for employment. In this study, Geographic Information System (GIS) was applied for the analysis and representation of spatio-temporal changes in LULC in Peshawar district and these results were linked with environmental aspects and Driver-Pressure-State-Impact-Response (DPSIR) framework approaches. For LULC classification, the Landsat freely available satellite imageries were used. The analysis revealed that the vegetation cover has increased from 37.8% of the total area to 71.3% during 1990-2020 and this change in vegetation is attributed to the government initiatives of Billion Tree Tsunami afforestation project after 2014 which has substantially decreased the barren land (from 66% in 1990 to 19% in 2020) in southeastern part of Peshawar district. Although, there was reduction in the vegetation cover in the past but due to extensive plantation between 2014 and 2020 resulted rapid increase in vegetation cover in the study area. The results of the present study detected a remarkable increase in built-up area which has increased almost 224.6% from 1990 to 2020. The study area population has increased from 2.12 million during 1998 to 4.26 million in 2017. The DPSIR results revealed that drivers and pressure have adverse effects on the carrying capacity of natural resources which have resulted deterioration of ecosystem. The resulted reduced capacity leading towards land degradation, loss of agricultural land, decline the groundwater level and resulted in pluvial flooding in Peshawar district. Government and environmental protection agency should implement the land use bylaws to reduce the rapid and unplanned urban growth and its negative impacts on natural environment.


Asunto(s)
Ecosistema , Urbanización , Monitoreo del Ambiente/métodos , Conservación de los Recursos Naturales , Sistemas de Información Geográfica , Agricultura
6.
Comput Intell Neurosci ; 2021: 2287531, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34754301

RESUMEN

The future directions and challenges for 6G-enabled wireless communication for IoT applications are mainly focused on quality of service (QoS). The selection criteria of mobility management (MM) protocol are mainly the total duration of the delay and packet loss rate during the MM procedure. This is called intelligent handover (IH) to designate a relay with a minimum delay. To solve the problem of handover, media access control (MAC) protocols are used to provide an intelligent protocol for QoS in real-time application in mobility. Moreover, changing the parameter to find the best protocol for mobile stations in WLAN is a good choice. This paper proposed a new QoS structure for the point coordination function that is based on a new intelligent enhanced distribution coordination function that suites with dynamic real-time applications and services. The paper addresses the distributed coordination function (DCF) with QoS-based intelligent mobility management in stations and other scenarios with enhanced distribution coordination function (EDCF) to find the result of throughput, retransmission attempts, delay, and data droop. In this paper, the remote topology comprises a few remote stations and one base station within the remote LAN. All remote stations are found that each station can distinguish a transmission from any other station, and there is portability within the proposed intelligent framework.


Asunto(s)
Redes de Comunicación de Computadores , Tecnología Inalámbrica , Ciudades
7.
Math Biosci Eng ; 18(5): 7010-7027, 2021 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-34517569

RESUMEN

The use of advanced technologies has increased drastically to maintain any sensitive records related to education, health, or finance. It helps to protect the data from unauthorized access by attackers. However, all the existing advanced technologies face some issues because of their uncertainties. These technologies have some lapses to provide privacy, attack-free, transparency, reliability, and flexibility. These characteristics are essential while managing any sensitive data like educational certificates or medical certificates. Hence, we designed an Industry 5.0 based blockchain application to manage medical certificates using Remix Ethereum blockchain in this paper. This application also employs a distributed application (DApp) that uses a test RPC-based Ethereum blockchain and user expert system as a knowledge agent. The main strength of this work is the maintenance of existing certificates over a blockchain with the creation of new certificates that use logistic Map encryption cipher on existing medical certificates while uploading into the blockchain. This application helps to quickly analyze the birth, death, and sick rate as per certain features like location and year.


Asunto(s)
Cadena de Bloques , Privacidad , Reproducibilidad de los Resultados , Tecnología
8.
Arh Hig Rada Toksikol ; 72(1): 42-52, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33787181

RESUMEN

This is a retrospective analysis of annual reports on occupational injuries issued by the national social insurance agency of the Kingdom of Saudi Arabia (KSA) for the years 2004 through 2016. For each criterion we calculated an index based on the equation NY/Nref x100, where NY is the number of occupational injuries by a specific criterion in a specific year Y, and Nref is the number of injuries in the corresponding criterion in the reference year, i.e. 2004. We also calculated the number of injuries to number of workers ratio (Ni/Nw ) for different occupations and economic sectors to get a clearer idea of the injury trends per worker. In terms of occupational injury rates (with respect to 2004), we observed increases in construction, financing & real estate (economic sectors), among engineers and technicians (occupations), in infections and secondary contusions (injury type), for upper and lower limbs (affected body parts), over falls and "other" causes. Most injuries occurred on Fridays, which is a weekend day in Saudi Arabia. We also observed increased recovery without disability (injury status). However, if we look at the number of occupational injuries per worker, we can see a decreasing trend over time for all occupations and economic sectors, most likely thanks to improved labour law and safety at work practices for insured workers. Our findings are similar to reports from other Persian Gulf countries and reflect current labour health and safety issues in the area.


Asunto(s)
Traumatismos Ocupacionales , Accidentes de Trabajo , Humanos , Traumatismos Ocupacionales/epidemiología , Ocupaciones , Estudios Retrospectivos , Arabia Saudita/epidemiología
9.
Results Phys ; 23: 103987, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36338375

RESUMEN

Nowadays under COVID 2019, e-learning has become a potential prop approach of technology in education that provides contemporary learners with authentic knowledge acquisitions. As a practical contribution, electronic examination (e-exam) is a novel approach in e-learning designed to solve traditional examination issues. It is a combination of assorted questions designed by specialized software to detect an individual's performance. Despite intensive research in this area, the performance of e-exams faces challenges such as authentication of the examinee's identity and answered papers. This paper aims to present the experiences of educational organizations in e-exam and e-evaluation as an essential tool of e-learning in various countries. The paper recommends that under the global pandemic COVID 2019 evaluating students using intensive continuous evaluation, including e-exam supported by authentication methods, which may help detect and reduce or even prevent student violations. The results show that the most used LMS tools were the Moodle and proprietary solutions which were 75% both among many other LMS tools i.e., Blackboard and eFront. The least develop countries are prefer to use open source and proprietary due to the zero cost of these solutions. The internet speed, cost and authenticity were the most challenges faced e-exams centers, which were 99%, 82%, and 68%, respectively.

10.
Contrast Media Mol Imaging ; 2021: 1101911, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34992507

RESUMEN

Quantum computing is a computer development technology that uses quantum mechanics to perform the operations of data and information. It is an advanced technology, yet the quantum channel is used to transmit the quantum information which is sensitive to the environment interaction. Quantum error correction is a hybrid between quantum mechanics and the classical theory of error-correcting codes that are concerned with the fundamental problem of communication, and/or information storage, in the presence of noise. The interruption made by the interaction makes transmission error during the quantum channel qubit. Hence, a quantum error correction code is needed to protect the qubit from errors that can be caused by decoherence and other quantum noise. In this paper, the digital system design of the quantum error correction code is discussed. Three designs used qubit codes, and nine-qubit codes were explained. The systems were designed and configured for encoding and decoding nine-qubit error correction codes. For comparison, a modified circuit is also designed by adding Hadamard gates.


Asunto(s)
Metodologías Computacionales , Teoría Cuántica
11.
Front Public Health ; 9: 792124, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35127623

RESUMEN

Today, disease detection automation is widespread in healthcare systems. The diabetic disease is a significant problem that has spread widely all over the world. It is a genetic disease that causes trouble for human life throughout the lifespan. Every year the number of people with diabetes rises by millions, and this affects children too. The disease identification involves manual checking so far, and automation is a current trend in the medical field. Existing methods use a single algorithm for the prediction of diabetes. For complex problems, a single model is not enough because it may not be suitable for the input data or the parameters used in the approach. To solve complex problems, multiple algorithms are used. These multiple algorithms follow a homogeneous model or heterogeneous model. The homogeneous model means the same algorithm, but the model has been used multiple times. In the heterogeneous model, different algorithms are used. This paper adopts a heterogeneous ensemble model called the stacked ensemble model to predict whether a person has diabetes positively or negatively. This stacked ensemble model is advantageous in the prediction. Compared to other existing models such as logistic regression Naïve Bayes (72), (74.4), and LDA (81%), the proposed stacked ensemble model has achieved 93.1% accuracy in predicting blood sugar disease.


Asunto(s)
Algoritmos , Diabetes Mellitus , Teorema de Bayes , Niño , Humanos
12.
Ecotoxicol Environ Saf ; 173: 182-191, 2019 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-30772708

RESUMEN

Since Ni-rich soils are a threat to the environment, growing edible crops on Ni-rich soils can pose a serious risk to human, animal, plant and ecosystem health and, hence, is considered as a challenging task for the researchers. Contrarily, limiting the bioavailability of Ni in such soils upon the addition of suitable amendments cum foliar spray of proteinogenic amino acids having an objective to alleviate stress to crop plants can considerably reduce the environmental risk. In this pot trail, we substantiate the effects of biochar (BR) and zeolite (ZL) addition in the soil along with proline (PN) spray on the resistance, and stress responses of wheat against Ni as well as on Ni translocation and accumulation in wheat plants grown on a Ni-rich soil contaminated by electroplating effluent. The treatments, applied with and without PN spray, involved: no amendment; BR; ZL; and a concoction of both amendments (BR50%+ZL50%). We found that BR50%+ZL50% treatment significantly immobilized Ni in the soil, reduced its accumulation in the shoot, root, and grain, blocked membrane lipid peroxidation and showed an improvement in photosynthetic parameters, the status of antioxidant activities, grain biochemistry and grain yield, compared to the control. Interestingly, exogenous PN spray caused a significant additive effect on the aforementioned parameters in the wheat plants grown on BR50%+ZL50% treated soil. Our results involved a reduced Ni bioavailability in wheat rhizosphere due to BR50%+ZL50% in soil and, furthermore, the additive effect of PN spray to scavenging ROS, obstructing peroxidation of lipid membrane and, thus providing resilience to wheat plant against Ni stress. The suggested technique can make Ni-rich soils suitable for cultivation and production of high-quality food by minimizing Ni bioavailability and toxicity to plants.


Asunto(s)
Carbón Orgánico/química , Níquel/química , Níquel/metabolismo , Prolina/química , Contaminantes del Suelo/química , Triticum/metabolismo , Zeolitas/química , Disponibilidad Biológica , Valor Nutritivo , Fotosíntesis , Suelo/química
13.
Int J Phytoremediation ; 21(8): 760-767, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30656967

RESUMEN

Phytoremediation is an important technique to remove heavy metals from contaminated soils due to its efficiency and cost-effectiveness. The present study was conducted to assess the synergistic role of 5-aminolevulinic acid (ALA) and citric acid (CA) in improving the phyto-extraction of chromium (Cr) by sunflower. Sunflower plants were grown in soil, spiked with different concentrations of Cr (0, 5, 10, 20 mg kg-1). Various concentrations of 5-ALA (0, 10, 20 mg L-1) and CA (0, 2.5, 5 mM) were applied exogenously at juvenile stage. A significant decrease was observed in biomass and agronomic traits of sunflower under Cr stress alone. Further, Cr toxicity significantly decreased the plant growth, soluble proteins and photosynthetic pigments. However, exogenously applied ALA and CA significantly improved the plants' physiological as well as agronomic attributes by lowering the production of reactive oxygen species and reducing electrolyte leakage. Moreover, Cr uptake was increased with increasing concentration of Cr in spiked soil, which was further enhanced by combined application of ALA and CA.


Asunto(s)
Helianthus , Contaminantes del Suelo , Ácido Aminolevulínico , Antioxidantes , Biodegradación Ambiental , Biomasa , Cromo , Ácido Cítrico , Fotosíntesis , Suelo
14.
East Mediterr Health J ; 24(10): 1010-1017, 2018 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-30582144

RESUMEN

BACKGROUND: The ongoing industrial and infrastructural development in Saudi Arabia carries a high risk of occupational injuries/diseases. AIMS: To compare trends in occupational injuries and diseases among Saudi and non-Saudi insured workers. METHODS: We used the index values method and slope (S) calculation to analyse the occupational injuries/diseases trends from data in the annual statistical reports published by the General Organization for Social Insurance between 2004 and 2014. Data for 10 565 993 (18.5%) Saudi insured workers (SIWs) and 46 402 079 (81.5%) non-Saudi insured workers (NSIWs) and 896 627 occupational injuries/diseases were analysed. RESULTS: The distribution of incidences of occupational injuries/diseases among NSIWs (93.5%) was 14 times higher than that of SIWs (6.5%). Occupational injuries/diseases were more likely to increase among NSIWs than SIWs, particularly in the construction, trade, financing and real estate economic activities, and engineering, technicians and service workers occupations. There was a general decreasing trend in occupational injuries/diseases until 2013. CONCLUSIONS: Non-Saudi insured workers were at high risk of occupational injuries/diseases, therefore, implementation of an effective injury prevention programme is required.


Asunto(s)
Enfermedades Profesionales/epidemiología , Traumatismos Ocupacionales/epidemiología , Ocupaciones/estadística & datos numéricos , Seguridad Social/estadística & datos numéricos , Accidentes de Trabajo/estadística & datos numéricos , Humanos , Incidencia , Enfermedades Profesionales/etnología , Salud Laboral , Traumatismos Ocupacionales/etnología , Factores de Riesgo , Arabia Saudita/epidemiología
15.
Environ Sci Pollut Res Int ; 25(25): 25390-25400, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29951756

RESUMEN

Phytoremediation is a cost-effective and eco-friendly technique for the removal of heavy metal-contaminated soils and water. The less availability and mobility of heavy metals in medium decreased the efficiency of this technique. The mobility and availability of these metals in the medium can be enhanced by the addition of organic chelators. The present study was conducted to investigate the possibility of glutamic acid (GA) in improving silver (Ag) phytoextraction by sunflower (Helianthus annuus L.). Different concentrations of Ag and GA were supplied in solution form in different combinations after defined intervals. Results depicted that increasing concentration of Ag significantly reduced the plant biomass, photosynthetic pigments, and antioxidant enzyme activities (like catalase, peroxidase, ascorbate, peroxidase, superoxide dismutase). Furthermore, Ag stress increased the Ag concentration and the production of reactive oxygen species (ROS) in sunflower plants. The addition of GA alleviated the Ag-induced toxicity in plants and enhanced Ag concentration and accumulation in sunflower. The addition of GA enhanced Ag accumulation in sunflower roots by 70, 79, 58, and 66% at 0-, 100-, 250-, and 500-µM Ag treatments, respectively, as compared to control plants. In conclusion, the results showed that Ag significantly reduced the physiological and biochemical attributes in term of reduced growth of sunflower and the addition of GA alleviated the Ag induced toxicity and enhanced Ag uptake. The results suggested that sunflower can be used as hyper-accumulator plant for the removal of Ag under GA. Further studies are required to understand the role of GA at gene and microscopic level in plants.


Asunto(s)
Ácido Glutámico/farmacología , Helianthus , Plata , Contaminantes del Suelo , Suelo/química , Adaptación Fisiológica/efectos de los fármacos , Antioxidantes/metabolismo , Biodegradación Ambiental , Catalasa/metabolismo , Ácido Glutámico/metabolismo , Helianthus/efectos de los fármacos , Helianthus/crecimiento & desarrollo , Helianthus/metabolismo , Metales Pesados/metabolismo , Metales Pesados/toxicidad , Estrés Oxidativo/efectos de los fármacos , Peroxidasa/metabolismo , Fotosíntesis/efectos de los fármacos , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Plata/metabolismo , Plata/toxicidad , Contaminantes del Suelo/metabolismo , Contaminantes del Suelo/toxicidad , Superóxido Dismutasa/metabolismo
16.
Ecotoxicol Environ Saf ; 151: 255-265, 2018 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-29353175

RESUMEN

Soil contamination with heavy metals is threatening the food security around the globe. Chromium (Cr) contamination results in poor quality and reduction in yield of crops. The present research was performed to figure out the Cr toxicity in sunflower and the ameliorative role of 5-aminolevulinic acid (ALA) as a plant growth regulator. The sunflower (FH-614) was grown under increasing concentration of Cr (0, 5, 10 and 20mgkg-1) alone and/or in combination with 5-ALA (0, 10 and 20mgL-1). Results showed that Cr suppressed the overall growth, biomass, gas exchange attributes and chlorophyll content of sunflower plants. Moreover, lower levels of Cr (5 and 10mgkg-1) increased the production of reactive oxygen species (ROS) and electrolyte leakage (EL) along with the activities of antioxidant enzymes i.e., superoxide dismutase (SOD), guaiacole peroxidase (POD), ascorbate (APX), catalase (CAT). But at higher concentration of Cr (20mgkg-1), the activities of these enzymes presented a declining trend. However, the addition of 5-ALA significantly alleviated the Cr-induced toxicity in sunflower plant and enhanced the plant growth and biomass parameters along with increased chlorophyll content, gas exchange attributes, soluble proteins and soil plant analysis development (SPAD) values by scavenging the ROS and lowering down the EL. The 5-ALA also enhanced the activities of antioxidant enzymes at all levels of Cr. The increase in Cr concentration in all plant parts such as leaf, root and stem was directly proportional to the Cr concentration in soil. The application of 5-ALA further enhanced the uptake of Cr and its concentration in the plants. To understand this variation in response of plants to 5-ALA, detailed studies are required on plant biochemistry and genetic modifications.


Asunto(s)
Ácido Aminolevulínico/farmacología , Cromo/toxicidad , Helianthus/metabolismo , Reguladores del Crecimiento de las Plantas/farmacología , Contaminantes del Suelo/toxicidad , Catalasa/metabolismo , Clorofila/análisis , Cromo/análisis , Relación Dosis-Respuesta a Droga , Helianthus/efectos de los fármacos , Peroxidasa/metabolismo , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/metabolismo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Contaminantes del Suelo/análisis , Estrés Fisiológico , Superóxido Dismutasa/metabolismo
17.
Ecotoxicol Environ Saf ; 145: 90-102, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28710950

RESUMEN

Soil and water contamination from heavy metals and metalloids is one of the most discussed and burning global issues due to its potential to cause the scarcity of healthy food and safe water. The scientific community is proposing a range of lab and field based physical, chemical and biological solutions to remedy metals and metalloids contaminated soils and water. The present study finds out a possibility of Chromium (Cr) extraction by sunflower from spiked soil under chelating role of citric acid (CA). The sunflower plants were grown under different concentrations of Cr (0, 5, 10 & 20mgkg-1) and CA (0, 2.5 & 5mM). Growth, biomass, gas exchange, photosynthesis, electrolyte leakage (EL), reactive oxygen species (ROS; malondialdehyde (MDA), hydrogen peroxide (H2O2) and the activities of antioxidant enzymes such as, superoxide dismutase (SOD), guaiacole values peroxidase (POD), ascorbate peroxidase (APX), catalase (CAT) were measured. The results depicted a clear decline in plant height, root length, leaf area, number of leaves and flowers per plant along with fresh and dry biomass of all parts of plant with increasing concentration of Cr in soil. Similar reduction was observed in chlorophyll a and b, total chlorophyll, carotenoids, soluble protein, gas exchange attributes and SPAD. The increasing concentration of Cr also enhanced the Cr uptake and accumulation in plant roots, stem and leaves along with the production of ROS and EL. The activities of antioxidant enzymes increased with increasing Cr concentration from 0 to 10mg, but decreased at 20mgkg-1 soil. The CA application significantly alleviated Cr-induced inhibition of plant growth, biomass, photosynthesis, gas exchange, soluble proteins and SPAD value. Presence of CA also enhanced the activities of all antioxidant enzymes and reduced the production of ROS and EL. The chelating potential of CA increased the concentration and accumulation of Cr in plant roots, stem and leaves. It is concluded that the sunflower can be a potential candidate for the remediation of Cr under CA treatment, while the possibility may vary with genotype, Cr level and CA concentration.


Asunto(s)
Cromo/análisis , Ácido Cítrico/farmacología , Helianthus/efectos de los fármacos , Contaminantes del Suelo/análisis , Antioxidantes/metabolismo , Biodegradación Ambiental , Biomasa , Clorofila/metabolismo , Clorofila A , Cromo/metabolismo , Helianthus/enzimología , Helianthus/crecimiento & desarrollo , Fotosíntesis/efectos de los fármacos , Contaminantes del Suelo/metabolismo
18.
Environ Sci Pollut Res Int ; 24(26): 21050-21064, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28726228

RESUMEN

The complex bio-geochemistry of soil allows pollutant to persist for a longer period of time which further decreased the fertility and natural composition of land. Nickel, an inorganic pollutant, coming from a wide range of industrial and manufacturing units possesses serious threat to soil degradation and crop productivity around the world. The present study was carried to evaluate the combined role of microwave irradiation (MR) and citric acid (CA) on the phytoextraction potential of Brassica napus L. under Ni stress. An initial seed germination test was conducted to select effective time scale of MR exposure. Highest seed germination was observed at exposure of 2.45 GHz frequency for 30 s. Healthy seeds of B. napus L. genotype Faisal Canola (RBN-03060) treated with MR at 2.45 GHz for 30 s were sown in plastic pots filled with 5 kg of soil. Nickel and CA applied exogenously in solution form with different combinations to both MR-treated and untreated B. napus plants. The MR-treated plants showed higher growth, biomass, photosynthetic pigments (Chl a, b, total, and carotenoids) and activities of antioxidant enzymes (SOD, POD, APX, CAT) as compared to untreated plants who showed higher reactive oxygen species (MDA, H2O2) and electrolyte leakage. Increasing Ni concentration significantly decreased the physiological and biochemical attributes of B. napus both in MR-treated and untreated plants. The addition of CA alleviated Ni-induced toxic effects in both MR-treated and untreated plants by improving antioxidant defense system. The degree of Ni stress mitigation was higher in MR-treated plants. The Ni concentration was higher in root, stem, and leaves of MR-treated plants under CA application as compared to untreated plants. The present study concluded that seeds treated with MR before sowing showed higher accumulation and concentration of Ni from soil, and this phenomenon boosted with the application of CA.


Asunto(s)
Biodegradación Ambiental , Ácido Cítrico/farmacología , Germinación , Microondas , Níquel/metabolismo , Contaminantes del Suelo/análisis , Antioxidantes/metabolismo , Biomasa , Brassica napus/efectos de los fármacos , Brassica napus/efectos de la radiación , Germinación/efectos de los fármacos , Germinación/efectos de la radiación , Peróxido de Hidrógeno/metabolismo , Fotosíntesis/efectos de los fármacos , Hojas de la Planta/metabolismo , Especies Reactivas de Oxígeno/metabolismo
19.
Environ Sci Pollut Res Int ; 24(21): 17669-17678, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28600794

RESUMEN

Phytoextraction is a cost-effective and eco-friendly technique for the removal of pollutants, mainly heavy metal(loids) especially from polluted water and metal-contaminated soils. The phytoextraction of heavy metals is, in general, limited due to the low availability of heavy metals in the growth medium. Organic chelators can help to improve the phytoextraction by increasing metal mobility and solubility in the growth medium. The present research was carried out to examine the possibility of citric acid (CA) in improving chromium (Cr) phytoextraction by Lemna minor (duckweed). For this purpose, healthy plants were collected from nearby marsh and grown in hydroponics under controlled conditions. Initial metal contents of both marsh water and plant were measured along with physico-chemical properties of the marsh water. Different concentrations of Cr and CA were applied in the hydroponics in different combinations after defined intervals. Continuous aeration was supplied and pH maintained at 6.5 ± 0.1. Results showed that increasing concentration of Cr significantly decreased the plant biomass, photosynthetic pigments, leaf area, and antioxidant enzyme activities (like catalase, ascorbate peroxidase, superoxide dismutase, peroxidase). Furthermore, Cr stress increased the Cr concentrations, electrolyte leakage, hydrogen peroxide, and malondialdehyde contents in plants. The addition of CA alleviated the Cr-induced toxicity in plants and further enhanced the Cr uptake and its accumulation in L. minor. The addition of CA enhanced the Cr concentration in L. minor by 6.10, 26.5, 20.5, and 20.2% at 0, 10, 100, and 200 µM Cr treatments, respectively, compared to the respective Cr treatments without CA. Overall, the results of the present study showed that CA addition may enhance the Cr accumulation and tolerance in L. minor by enhancing the plant growth and activities of antioxidant enzymes.


Asunto(s)
Araceae , Cromo/química , Ácido Cítrico , Antioxidantes , Hidroponía , Raíces de Plantas , Contaminantes del Suelo
20.
Environ Sci Pollut Res Int ; 24(20): 16845-16859, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28573560

RESUMEN

Chromium (Cr) is a biologically non-essential, carcinogenic and toxic heavy metal. The cultivation of Cr-tolerant genotypes seems the most favorable and environment friendly strategy for rehabilitation and remediation of Cr-contaminated soils. To prove this hypothesis and identify the Cr tolerance, the present study was performed to assess the physiological and biochemical response of sunflower genotypes to Cr stress. The seeds of six sunflower hybrids, namely FH-425, FH-600, FH-612, FH-614, FH-619, and FH-620, were grown in spiked soil for 12 weeks under increasing concentrations of Cr (0, 5, 10, and 20 mg kg-1). A seed germination test was also run under different concentrations of Cr (0, 5, 10, 200 mM) in petri dishes. Plants were harvested after 12 weeks of germination. Different plant attributes such as growth; biomass; photosynthesis; gas exchange; activity of antioxidant enzymes, i.e., superoxide dismutase (SOD), guaiacol peroxidase (POD), ascorbate (APX), and catalases (CAT); reactive oxygen species (ROS); lipid peroxidation; electrolyte leakage; and Cr concentration as well as accumulations in all plant parts were studied for the selection of the most Cr-tolerant genotype. Increasing concentration of Cr in soil triggered the reduction of all plant parameters in sunflower. Cr stress increased electrolyte leakage and production of reactive oxygen species which stimulated the activities of antioxidant enzymes and gas exchange attributes of sunflower. Chromium accumulation in the root and shoot increased gradually with increasing Cr treatments and caused reduction in overall plant growth. The accumulation of Cr was recorded in the order of FH-614 > FH-620 > FH-600 > FH-619 > FH-612 > FH-425. The differential uptake and accumulation of Cr by sunflower hybrids may be useful in selection and breeding for Cr-tolerant genotypes.


Asunto(s)
Cromo/farmacología , Helianthus/fisiología , Contaminantes del Suelo/farmacología , Antioxidantes , Contaminación Ambiental , Suelo , Estrés Fisiológico
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