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Результаты 4041-4050 из 7,291
A hybrid statistical decision-making optimization approach for groundwater vulnerability considering uncertainty Полный текст
2022
Gharakezloo, Yalda Norouzi | Nikoo, Mohammad Reza | Karimi-Jashni, Ayoub | Mooselu, Mehrdad Ghorbani
Recognizing the vulnerable areas for contamination is a feasible way to protect groundwater resources. The main contribution of the paper is developing a hybrid statistical decision-making model for evaluating the vulnerability of Shiraz aquifer, southern Iran, with modified DRASTIC (depth to the water table, net recharge, aquifer media, soil media, topography, impact of the vadose zone, and hydraulic conductivity) by using the genetic algorithm (GA), the analytical hierarchy process (AHP) method, and factorial analysis (FA). First, considering the variation of the uncertain parameters, 32 scenarios were defined to perform factorial analysis. Then using the AHP method and GA, DRASTIC parameters were rated and weighted in all scenarios. To achieve the optimal weights for parameters, the objective function in GA was maximizing the correlation coefficient between the vulnerability index and the nitrate concentration. The single and interactive effects of parameters on groundwater vulnerability were analyzed by factorial analysis. The results revealed that the net recharge had the highest single effect, and the resulted effect between net recharge and hydraulic conductivity was the most significant interactive effect on the objective function. Besides, the variation of aquifer media does not change the objective function. The application of the proposed method leads to a precise groundwater vulnerability map. This research provides valuable knowledge for assessing groundwater vulnerability and enables decision-makers to apply groundwater vulnerability information in future water resources management plans.
Показать больше [+] Меньше [-]Ecological efficiency evaluation and driving factor analysis of the coupling coordination of the logistics industry and manufacturing industry Полный текст
2022
Su, Juan | Shen, Tong | Jin, Shuxin
The coupling coordination of the logistics industry and manufacturing industry is conducive to the sustainable development of logistics and manufacturing and the stability of sustainable supply chain. The logistics and manufacturing industries are not only the basic industries that support social development, but also the industries with high carbon emissions. This paper constructs the measurement system of coupling coordinating ecological efficiency of two industries based on carbon emission constraints and finds out the driving factors affecting ecological efficiency, which is of great significance to the low-carbon coordinated development of the two industries in the future. Firstly, this paper classifies the carbon emissions from the logistics industry and manufacturing industry as undesirable outputs and evaluates the ecological efficiency of the logistics industry (LEE) and manufacturing industry (MEE) in the three urban agglomerations from 2006 to 2019 by using the unexpected slacks-based measure (SBM) model. Secondly, the coupling coordination method is used to analyze the coupling coordination scheduling of industrial ecological efficiency (MLCC). Finally, the spatial econometric model is used to analyze the driving factors of the MLCC. The results show that during the study period, the coupling coordination of the three urban agglomerations continued to grow, the Pearl River Delta coupling coordination is the highest, the Yangtze River Delta coupling coordination grew the fastest, and the Beijing–Tianjin–Hebei coupling coordination grew slightly slower. The development during the 13th Five-Year Plan period is obviously faster than that during the 11th and 12th Five-Year Plan. The empirical analysis results of spatial econometrics show that the driving factors have an impact on the coupling coordination degree of the three urban agglomerations, but the significance of each factor is different. The driving factors have significant spatial heterogeneity. The three urban agglomerations should formulate low-carbon industry development policies in line with local development according to the actual situation of each region and local conditions.
Показать больше [+] Меньше [-]Free radical biology in neurological manifestations: mechanisms to therapeutics interventions Полный текст
2022
Tripathi, Rahul | Gupta, Rohan | Sahu, Mehar | Srivastava, Devesh | Das, Ankita | Ambasta, Rashmi K | Kumar, Pravir
Recent advancements and growing attention about free radicals (ROS) and redox signaling enable the scientific fraternity to consider their involvement in the pathophysiology of inflammatory diseases, metabolic disorders, and neurological defects. Free radicals increase the concentration of reactive oxygen and nitrogen species in the biological system through different endogenous sources and thus increased the overall oxidative stress. An increase in oxidative stress causes cell death through different signaling mechanisms such as mitochondrial impairment, cell-cycle arrest, DNA damage response, inflammation, negative regulation of protein, and lipid peroxidation. Thus, an appropriate balance between free radicals and antioxidants becomes crucial to maintain physiological function. Since the 1brain requires high oxygen for its functioning, it is highly vulnerable to free radical generation and enhanced ROS in the brain adversely affects axonal regeneration and synaptic plasticity, which results in neuronal cell death. In addition, increased ROS in the brain alters various signaling pathways such as apoptosis, autophagy, inflammation and microglial activation, DNA damage response, and cell-cycle arrest, leading to memory and learning defects. Mounting evidence suggests the potential involvement of micro-RNAs, circular-RNAs, natural and dietary compounds, synthetic inhibitors, and heat-shock proteins as therapeutic agents to combat neurological diseases. Herein, we explain the mechanism of free radical generation and its role in mitochondrial, protein, and lipid peroxidation biology. Further, we discuss the negative role of free radicals in synaptic plasticity and axonal regeneration through the modulation of various signaling molecules and also in the involvement of free radicals in various neurological diseases and their potential therapeutic approaches. The primary cause of free radical generation is drug overdosing, industrial air pollution, toxic heavy metals, ionizing radiation, smoking, alcohol, pesticides, and ultraviolet radiation. Excessive generation of free radicals inside the cell R1Q1 increases reactive oxygen and nitrogen species, which causes oxidative damage. An increase in oxidative damage alters different cellular pathways and processes such as mitochondrial impairment, DNA damage response, cell cycle arrest, and inflammatory response, leading to pathogenesis and progression of neurodegenerative disease other neurological defects.
Показать больше [+] Меньше [-]Enhanced photocatalytic activity and charge carrier separation of CNT/TiO2/WO3/CdS catalyst for the visible-light photodegradation of reactive blue 19 Полный текст
2022
Bagheri, Marzieh | Vesali-Naseh, Masoud | Farhadian, Mehrdad
The novel quaternary CNT/TiO₂/WO₃/CdS nanostructure was fabricated to be employed in the photocatalytic degradation of reactive blue 19 (RB19) under the visible light irradiation. The physicochemical properties of the pure TiO₂, CNT/TiO₂, CNT/TiO₂/WO₃, and CNT/TiO₂/WO₃/CdS were characterized using XRD, FTIR, FESEM, EDX, DRS, PL, and BET analyses. The photodegradation results showed that the optimum weight percentage of CNT, WO₃, and CdS was 4%, 35%, and 5%, respectively. The highest RB19 degradation efficiency of CNT/TiO₂/WO₃/CdS was achieved 97%. Besides, the central composite design was applied to model and optimize the photocatalytic activity of CNT/TiO₂/WO₃/CdS nanocatalyst and assess the effects of processing variables including RB19 concentration, catalyst concentration, pH, and irradiation time on the response. RB19 concentration and pH had the most and the second most significant role in the removal efficiency. While increasing the catalyst concentration and irradiation time positively enhanced the removal efficiency to more than 82%, increasing the pH and dye concentration showed the remarkable hindering effects on the removal efficiency by about 45% reduction. The reusability of the synthesized catalysts was studied under the optimum conditions as follows: [RB19] = 25 mg/L, [catalyst] = 1 g/L, pH of 4, and irradiation time = 2 h. The COD and TOC analyses were also conducted during photodegradation process. The COD and TOC removal efficiencies were achieved about 67% and 62%, respectively.
Показать больше [+] Меньше [-]Effects of COVID-19 lockdown on water quality, microbial extracellular enzyme activity, and sediment-P release in the Ganga River, India Полный текст
2022
Singh, Madhulika | Pandey-Mishra, Usha | Pandey, Jitendra
This study investigates possible improvement in water quality and ecosystem functions in the Ganga River as influenced by COVID-19 lockdown in India. A total of 132 samples were collected during summer-2020 low flow (coinciding COVID-19 lockdown) for water (sub-surface and sediment-water interface) and 132 samples separately for sediment (river bottom and land-water interface) considering 518-km main river stem including three-point sources (one releases urban sewage and the other two add metal-rich industrial effluents) and a pollution-impacted tributary. Parameters such as dissolved oxygen deficit and the concentrations of carbon, nutrients (N and P), and heavy metals were measured in water. Sediment P-release was measured in bottom sediment whereas extracellular enzymes (EE; alkaline phosphatase, FDAase, protease, and β-D-glucosidase) and CO₂ emission were measured at land-water interface to evaluate changes in water quality and ecosystem functions. The data comparisons were made with preceding year (2019) measurements. Sediment-P release and the concentrations of carbon, nutrients, and heavy metals declined significantly (p<0.05) in 2020 compared to those recorded in 2019. Unlike the preceding year, we did not observe benthic hypoxia (DO <2.0 mg L⁻¹) in 2020 even at the most polluted site. The EE activities, which declined sharply in the year 2019, showed improvement during the 2020. The stability coefficient and correlative evidences also showed a large improvement in the water quality and functional variables. Positive changes in functional attributes indicated a transient recovery when human perturbations withdrawn. The study suggests that timing the ecosystem recovery windows, as observed here, may help taking management decision to design mitigation actions for rivers to recover from anthropogenic perturbations.
Показать больше [+] Меньше [-]Parameter setting of meta-heuristic algorithms: a new hybrid method based on DEA and RSM Полный текст
2022
Shadkam, Elham
The parameter setting of meta-heuristic algorithms is one of the most effective issues in the performance of meta-heuristic algorithms and is usually done experimentally which is very time-consuming. In this research, a new hybrid method for selecting the optimal parameters of meta-heuristic algorithms is presented. The proposed method is a combination of data envelopment analysis method and response surface methodology, called DSM. In addition to optimizing parameters, it also simultaneously maximizes efficiency. In this research, the hybrid DSM method has been used to set the parameters of the cuckoo optimization algorithm to optimize the standard and experimental functions of Ackley and Rastrigin. In addition to standard functions, in order to evaluate the performance of the proposed method in real problems, the parameter of reverse logistics problem for COVID-19 waste management has been adjusted using the DSM method, and the results show better performance of the DSM method in terms of solution time, number of iterations, efficiency, and accuracy of the objective function compared to other.
Показать больше [+] Меньше [-]Targeting natural products against SARS-CoV-2 Полный текст
2022
Al-Harrasi, Ahmed | Behl, Tapan | Upadhyay, Tanuj | Chigurupati, Sridevi | Bhatt, Shvetank | Sehgal, Aayush | Bhatia, Saurabh | Singh, Sukhbir | Sharma, Neelam | Vijayabalan, Shantini | Palanimuthu, Vasanth Raj | Das, Suprava | Rajwinder Kaur, | Aleya, Lotfi | Bungau, Simona
The human coronavirus disease (COVID-19) pandemic is caused by a novel coronavirus; the Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2). Natural products, secondary metabolites show positive leads with antiviral and immunotherapy treatments using genomic studies in silico docking. In addition, it includes the action of a mechanism targeting the SARS-CoV-2. In this literature, we aimed to evaluate the antiviral movement of the NT-VRL-1 unique terpene definition to Human coronavirus (HCoV-229E). The effects of 19 hydrolysable tannins on the SARS-CoV-2 were therefore theoretically reviewed and analyzed utilising the molecular operating surroundings for their C-Like protease 3CLpro catalytic dyad residues Angiotensin converting enzyme-2 (MOE 09). Pedunculagin, tercatan, and castalin were detected as interacting strongly with SARS-receptor Cov-2’s binding site and catalytic dyad (Cys145 and His41). SARS-CoV-2 methods of subunit S1 (ACE2) inhibit the interaction of the receiver with the s-protein once a drug molecule is coupled to the s-protein and prevent it from infecting the target cells in alkaloids. Our review strongly demonstrates the evidence that natural compounds and their derivatives can be used against the human coronavirus and serves as an area of research for future perspective.
Показать больше [+] Меньше [-]Potentially toxic elements in invasive fish species Prussian carp (Carassius gibelio) from different freshwater ecosystems and human exposure assessment Полный текст
2022
Milošković, Aleksandra | Stojković Piperac, Milica | Kojadinović, Nataša | Radenković, Milena | Đuretanović, Simona | Čerba, Dubravka | Milošević, Đurađ | Simić, Vladica
Concentrations of Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, Sn, and Zn were detected in the muscle and gills of Prussian carp from three different freshwater ecosystems: isolated ponds and the South Morava River in Serbia, and Kopačko Lake in complex wetland ecosystem of the Kopački Rit Nature Reserve in Croatia. The main goals of the present research were to assess the concentrations of potentially toxic elements (PTEs) in the muscle and gills of Prussian carp (Carassius gibelio), to examine whether abiotic factors from three different freshwater ecosystems affect the accumulation of PTEs in fish tissues, and to estimate the human health risk resulting from fish consumption. There were only six concentrations of PTEs in the gill tissue (Cr, Hg, Mn, Pb, Sn, and Zn) that were not significantly different among the different freshwater ecosystems. In the muscles, the differences were much less visible. Kopačko Lake distinguished with the highest values of metal pollution index (MPI) for muscles (0.24) and isolated ponds with the highest values of MPI for gills (0.8). The redundancy analysis (RDA) showed that concentrations of Al, Mn, Zn, Cu, and Fe in the gill tissue were significantly correlated with the environmental variables. In contrast, the RDA based on element concentrations in the fish muscles indicated no significant relationship with the environment. Isolated ponds, with no inflow of freshwater, stand out as the most polluted, followed by Kopačko Lake with occasional floods. Flowing freshwater ecosystem South Morava River can be single out as at least polluted with PTEs. The target hazard quotients (THQ) and hazard index (HI) suggested there were no significant noncarcinogenic health risks. The target carcinogenic risk factor (TR) for As and Pb confirmed there were no cancer risks related to human fish consumption. Since the elevated concentrations of toxic Cd and As in Prussian carp were estimated, an early warning should be assumed, especially for fishing activities in these areas.
Показать больше [+] Меньше [-]A CFD-based approach to optimize operating parameters of a flow-through scintillation cell for measurement of 220Rn in indoor environments Полный текст
2022
Agarwal, Tarun Kumar | Gaware, Jitendra Jalindar | Sapra, Balvinder Kaur
The measurements and monitoring of ²²²Rn/²²⁰Rn have been of emerging interest in occupational environments particularly in radium/thorium handling facilities and environments with monazite deposits for the inhalation dosimetry. The performance of a flow-through Lucas scintillation cell (LSC) for long run ²²⁰Rn measurements, depends upon the exact distribution pattern of ²²⁰Rn and its decay products in the LSC which can vary with the design of inlet path and flow rates. In this work, the CFD technique has been used to study the concentration profiles of ²²⁰Rn and its decay products in LSC for varying flow rates and inlet needle lengths. The variation of alpha production efficiency (ηα) is computed and analyzed for each case; aiming to select the best operating range of parameters for the optimum performance of LSC for ²²⁰Rn measurements. It is seen that LSC can be operated in the flow rate ranging from 0.6 to 1 lpm with inlet needle length varying from 22.5 to 45 mm for improved sensitivity.
Показать больше [+] Меньше [-]Adsorption of Metals by Chitosan Beads in Sugarcane Cultivation Streams: Implications for Chironomus sancticaroli Insect Larvae (Diptera: Chironomidae) Полный текст
2022
Geromel-Costa, Camila | Bernegossi, Aline Christine | Moura, Lidia | Corbi, Juliano José
Streams located in areas of sugarcane cultivation receive elevated concentrations of metal ions from soils of adjacent areas. This process may cause impacts on streams located in the adjacent areas. The contamination of stream sediments can lead to bioaccumulation of such metal by aquatic organisms, such as benthic invertebrates. Chitosan beads, a biopolymer that demonstrates a high affinity for metal, are simple to prepare under the laboratory, have a low overall cost, and can be used for removing metals from aquatic sediments. This work studied the use of Chitosan beads in metal adsorption from sediments of streams located in areas of sugarcane cultivation and evaluated the effects on the survival of Chironomus sancticaroli insect larvae. Acute bioassays were performed in two scenarios, in the presence and in the absence of chitosan beads. The bioassay consisted of the exposure of 10 IV instar of Chironomus sancticaroli larvae, for 96 h in five stream sediments. The results showed that chitosan beads (containing only 5.5% of chitosan) adsorbed metals in the order of Mg > Zn > Mn > Cd. The statistical results demonstrated that the addition of chitosan to the bioassays allowed a high larvae survival. The outcomes showed evidence of the viability of chitosan in remediating the metal impacts and showed a positive influence on aquatic biota.
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