Reactive oxygen species (ROS) – the byproducts of aerobic metabolism – influence numerous aspects of the plant life cycle and environmental response mechanisms. In plants, ROS act like a double-edged ...sword; they play multiple beneficial roles at low concentrations, whereas at high concentrations ROS and related redox-active compounds cause cellular damage through oxidative stress. To examine the dual role of ROS as harmful oxidants and/or crucial cellular signals, this review elaborates that (i) how plants sense and respond to ROS in various subcellular organelles and (ii) the dynamics of subsequent ROS-induced signaling processes. The recent understanding of crosstalk between various cellular compartments in mediating their redox state spatially and temporally is discussed. Emphasis on the beneficial effects of ROS in maintaining cellular energy homeostasis, regulating diverse cellular functions, and activating acclimation responses in plants exposed to abiotic and biotic stresses are described. The comprehensive view of cellular ROS dynamics covering the breadth and versatility of ROS will contribute to understanding the complexity of apparently contradictory ROS roles in plant physiological responses in less than optimum environments.
•The evolution of ROS as harmful oxidants and/or universal signaling metabolites in eukaryotic cells is critically appraised.•A comprehensive view of cellular ROS dynamics, with particular emphasis on crosstalk between cellular compartments in mediating their redox state spatially and temporally is discussed.•The beneficial roles of ROS to regulate a diverse array of plant cellular responses under stress conditions are highlighted.
In this decade, the use of nano particles (NPs) against bacterial growth is increasing day by day due to remarkable alternative properties compared to molecular antibiotics. Thus, the use of iron ...oxide nanoparticles (IONPs) has proven one of the most important transition metals oxide-based remedy in nanotechnological advances and biological applications due to enriched biocompatibility of iron. In this study synthesis of IONPs was carried out via co-precipitation method. The crystallographic morphology of the synthesized particles was studied via X-ray diffraction which revealed cubic structure of the particles, whereas, the spinal shaped morphology of the prepared NPs was confirmed from scanning electron microscopy. Likewise, the presence of the major elements in the sample was determined through energy dispersive X-ray analysis characterization. Bactericidal effect of the NPs was assessed at pre-defined concentrations (50 and 100 μg/ml) against Gram +ve bacteria Staphylococcus aureus, Gram -ve bacteria Shigella dysentry and Escherichia coli. Bacterial strains, which demonstrate the potential of NPs. The purpose of this study was assessing the structure of the synthesized NPs for protective effect against harmful bacterial activity.
Use of antimicrobials in the treatment and prevention of COVID-19, caused by novel coronavirus SARS-CoV-2, is on the rise. The increased use of antimicrobials can have serious consequences on the ...environment. Antibiotics have had a reasonable role in bacterial co-infections with regards to the management of COVID-19. However, recent evidences suggest that there has been injudicious prescription of antimicrobials. Moreover, a large number of people are self-medicating with antibiotics in a misguided attempt to protect themselves from the virus. This practice is especially prevalent in developing communities. Although common soaps are effective at inactivating enveloped viruses, such as the SARS-CoV-2, use of antibacterial products bearing biocides has increased during this pandemic. Current wastewater treatment techniques are unable to offer complete elimination of antibacterial biocides. These compounds can then accumulate in different environmental compartments thus, disrupting the functioning of native microbes. These microbes are involved in the biogeochemical cycling of elements and environmental remediation. In addition, the presence of antimicrobial elements in the environment can stimulate antimicrobial resistance. Concrete actions are needed to address this issue. Development of an antimicrobial policy specific for COVID-19 is urgently needed. Investments into improving wastewater infrastructure as well as public awareness is crucial. Moreover, global monitoring programs and multidisciplinary collaborations are required to understand the environmental impact of this pandemics.
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•COVID-19 is caused by novel coronavirus SARS-CoV-2.•Injudicious use of antimicrobials is rising in COVID-19 treatment and prevention.•Increased loading of antimicrobials would affect the environment.•Investments are called in wastewater infrastructure and public awareness.
It is evident from previous reports that 5-aminolevulinic acid (ALA), like other known plant growth regulators, is effective in countering the injurious effects of heavy metal-stress in oilseed rape ...(Brassica napus L.). The present study was carried out to explore the capability of ALA to improve cadmium (Cd2+) tolerance in B. napus through physiological, molecular, and proteomic analytical approaches. Results showed that application of ALA helped the plants to adjust Cd2+-induced metabolic and photosynthetic fluorescence changes in the leaves of B. napus under Cd2+ stress. The data revealed that ALA treatment enhanced the gene expressions of antioxidant enzyme activities substantially and could increase the expression to a certain degree under Cd2+ stress conditions. In the present study, 34 protein spots were identified that differentially regulated due to Cd2+ and/or ALA treatments. Among them, 18 proteins were significantly regulated by ALA, including the proteins associated with stress related, carbohydrate metabolism, catalysis, dehydration of damaged protein, CO2 assimilation/photosynthesis and protein synthesis/regulation. From these 18 ALA-regulated proteins, 12 proteins were significantly down-regulated and 6 proteins were up-regulated. Interestingly, it was observed that ALA-induced the up-regulation of dihydrolipoyl dehydrogenase, light harvesting complex photo-system II subunit 6 and 30S ribosomal proteins in the presence of Cd2+ stress. In addition, it was also observed that ALA-induced the down-regulation in thioredoxin-like protein, 2, 3-bisphosphoglycerate, proteasome and thiamine thiazole synthase proteins under Cd2+ stress. Taken together, the present study sheds light on molecular mechanisms involved in ALA-induced Cd2+ tolerance in B. napus leaves and suggests a more active involvement of ALA in plant physiological processes than previously proposed.
Floods are among the most devastating and recurring natural hazards and have caused extensive economic losses to human lives and infrastructures around the world. Swat valley in northern Pakistan is ...prone to frequent floods and was severely affected by the Flood2010 in the recent past. Flood hazard assessment is a non-structural strategy for flood mitigation in addition to the structure measure. In this study, 60 km long reach of the River Swat (Khwazakhela Bridge–Chakdara Bridge) was modeled using the HEC-RAS 2D model and high-resolution 12-m WorldDEM. The model was calibrated and validated for only historical maximum flood event, i.e., Flood2010 using Manning’s ‘n’ values, flood stage at the Chakdara Bridge and satellite imagery-based Flood2010-observed extent. In addition, flood model sensitivity to the DEM was carried out and simulated maximum depth was 12, 13, 14, and 25 m for the 12-m WorldDEM, 30-m SRTM, 30-m ALOS and 30-m ASTER DEMs, respectively. Designed hydrographs were prepared for 2, 5, 10, 25, 50, and 100-year return periods based on the Flood2010-observed hydrograph. Finally, the model was simulated for 2, 5, 10, 25, 50, and 100-year return periods with full momentum equation as the calculation method. Simulated extents based on the 12-m WorldDEM were used for the preparation of flood hazard maps. Landcover exposure to the designed flood events shows that agriculture including orchards is the major potential affected class with affected areas up to 55 Km
2
. The developed flood hazard maps will enable the policy makers to mainstream flood hazard assessment in the planning and development process for mitigating flood hazard in Swat Valley.
Renewable energy for power generation is gaining attention around the world, and for Pakistan, these resources can fulfill the present and future energy demands of the country. Though the potential ...of renewable energy resources has been assessed in earlier studies, their assessment did not consider the most promising technologies. Moreover, their estimation was static and the future renewable resource potential was not estimated. This study estimates the current and future potential of renewable energy sources for power generation by employing most promising technologies. The technical potential of solar energy from solar photovoltaic and parabolic trough thermal technologies for power generation is estimated to be 149GW in 2010 and 169GW in 2050. The suitable area for wind energy generation is available for the capacity installation of 13GW. The potential from biomass energy sources is 5GW in 2010 and could be 15GW in 2050. Small hydro installed capacity under current circumstances can reach 3GW installed capacity. The current national plans are resulting in exploitation of wind and small hydro plants, but a large technical potential of solar and biomass technologies also exists. The study results clearly demonstrate that renewable energy sources can supplement the energy needs of Pakistan and can provide a sustainable energy base.
Presence of speech and motion artifacts has been shown to impact the performance of wearable sensor systems used for automatic detection of food intake. This work presents a novel wearable device ...which can detect food intake even when the user is physically active and/or talking. The device consists of a piezoelectric strain sensor placed on the temporalis muscle, an accelerometer, and a data acquisition module connected to the temple of eyeglasses. Data from 10 participants was collected while they performed activities including quiet sitting, talking, eating while sitting, eating while walking, and walking. Piezoelectric strain sensor and accelerometer signals were divided into non-overlapping epochs of 3 s; four features were computed for each signal. To differentiate between eating and not eating, as well as between sedentary postures and physical activity, two multiclass classification approaches are presented. The first approach used a single classifier with sensor fusion and the second approach used two-stage classification. The best results were achieved when two separate linear support vector machine (SVM) classifiers were trained for food intake and activity detection, and their results were combined using a decision tree (two-stage classification) to determine the final class. This approach resulted in an average F1-score of 99.85% and area under the curve (AUC) of 0.99 for multiclass classification. With its ability to differentiate between food intake and activity level, this device may potentially be used for tracking both energy intake and energy expenditure.
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