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Potential of local plant leaves as natural coagulant for turbidity removal Texte intégral
2022
Ahmad, Azmi | Abdullah, Siti Rozaimah Sheikh | Hasan, Hassimi Abu | Othman, Ahmad Razi | Ismail, Nur ‘Izzati
The performance of local plants was tested using synthetic turbid water resembling real wastewater by measuring their ability to remove turbidity. The selected plants were A. indica, S. palustris, D. linearis, S. polyanthum, M. esculenta, P. sarmentosum, and M. malabathricum which can easily be found locally. The experiment was run based on coagulant dosages varied from 0 to 10 g/L for each plant with a rapid mixing speed at 180 rpm for 3 min, slow mixing speed at 10 rpm for 20 min, and settling time for 30 min. The results demonstrated that each plant has been capable of reducing turbidity by different amounts, with an increase in the coagulant dosage. The optimum coagulant dosages achieved for A. indica, S. palustris, S. polyanthum, and D. linearis were 10 g/L with turbidity removal at 26.9%, 24.9%, 24.9%, and 17.5%, respectively. P. sarmentosum and M. esculenta attained optimum coagulant dosages at 5 g/L with turbidity removal at 24.2% and 22.2%, and lastly M. malabathricum at 0.1 g/L (12.2%). P. sarmentosum was suggested to the best natural coagulant which achieved the highest removal of turbidity with a low dosage used.
Afficher plus [+] Moins [-]Expanding arsenal against diabetes mellitus through nanoformulations loaded with glimepiride and simvastatin: A comparative study Texte intégral
2022
Pandey, Narendra Kumar | Singh, Sachin Kumar | Kumar, Bimlesh | Gulati, Monica | Vishwas, Sukriti | Khursheed, Rubiya | Dureja, Harish | Chellappan, Dinesh Kumar | Jha, Niraj Kumar | Sharma, Ankur | Jha, Saurabh Kumar | Gupta, Piyush Kumar | Gupta, Saurabh | Gupta, Gaurav | Prasher, Parteek | Dua, Kamal
Type 2 diabetes mellitus is one of the most common and life-threatening diseases found across the globe. It occurs due to insulin resistance (IR). Major causes of IR include obesity, sedentary life style and hyperlipidemia. Glimepiride (GLM) is one of the most common oral sulphonyl ureas that is being used to treat diabetes and Simvastatin (SIM) is one of the most common statins that is used to treat hyperlipidaemia. However, both the drugs suffer from dissolution rate limited oral bioavailability. Hence, the aim of present study was to develop two different nanoformulations viz. nanosuspension and self-nanoemulsifying drug delivery systems (SNEDDS) and evaluate their potential in treating type 2 diabetes mellitus on streptozotocin (STZ) induced rats. In the present study two such drugs, GLM and SIM were co-formulated into nanosuspension (NS) as well as self-nanoemulsifying drug delivery systems (L-SNEDDS). Both formulations were spray dried for solidification and evaluated for their antidiabetic potential against high fat diet and streptozotocin induced rat model. The study showed significant (p < 0.05) decrease in lipid/cholesterol and blood glucose levels and significant increase in antioxidant levels in the rats treated with NS and SNEDDS containing the drugs alone as well as their combination as compared to their unprocessed forms. However, the efficacy was more prominent in case of combination possibly due to dual benefits i.e., decrease in IR due to statin and control of blood glucose level. Among NS and SNEDDS, NS was found more efficacious than that of the SNEDDS possibly due to higher enhancement of oral bioavailability in case of NS.
Afficher plus [+] Moins [-]Analysis on the spatial differentiation characteristics of poverty risk caused by disaster under the stress of geological disasters: a case study of Sichuan Province Texte intégral
2022
Xiang, Mingshun | Duan, Linsen | Wei, Fengran | Yang, Jin | Li, Wenheng | Wang, Chunjian | Yang, Wenbo | Deng, Qiuchi
Research on the poverty risk caused by geological disasters in disaster-prone areas is a useful exploration to coordinate social economic development with disaster prevention and reduction, and is of great significance to the regional sustainable development. Based on statistical data and spatial data, this paper takes Sichuan Province as the typical research area. Remote sensing and geographic information technology are used to study the poverty risk caused by disasters based on the quantitative evaluation of geological disasters risk and regional development level. The spatial differentiation characteristics of poverty risk caused by disasters are explored on the 1 km × 1 km grid scale. The results indicate that (1) the overall risk of geological disasters in Sichuan Province is relatively high, with high and relatively high risk areas accounting for more than 40% and low and relatively low risk areas accounting for less than 30%. The risks in Mountain and Ravine Areas are significantly higher than other areas. (2) The regional development level in Sichuan Province is relatively high, but with significant spatial differences. The development level of high-altitude areas and remote mountainous areas is quite different from that of the Chengdu Plain in the middle Sichuan Province. The uneven development in the east, middle, and west is a prominent problem. (3) The poverty risk caused by disasters is high, and the spatial pattern presents a characteristic of “high in the west and low in the east” with high positive spatial correlation. High-High Cluster Areas are mainly distributed in western and southwestern Sichuan. Low-Low Outlier Areas are mainly distributed in Chengdu Plain and Hilly Areas of Sichuan Basin. High-Low Outlier and Low–High Outlier Areas occupy a relatively small percentage with scattered distribution. This paper provides some theoretical support for policy formulation and management of coordinated development of regional socioeconomic and ecological environment.
Afficher plus [+] Moins [-]Hazards of toluene storage tanks in a petrochemical plant: modeling effects, consequence analysis, and comparison of two modeling programs Texte intégral
2022
Barjoee, Saeed Shojaee | Elmi, Mohammad Reza | Varaoon, Vahid Talebi | Keykhosravi, Seyed Saeed | Karimi, Farshid
The leakage of toluene from damaged tanks can threaten both workers and the environment; ergo, the effects and consequences of toluene leaks can be modeled and quantified to aid in emergency planning and response management. This study modeled the effects and consequences on various scenarios of toluene release via the ALOHA and PHAST programs: evaporation puddle formation, dispersion of toxic and flammable vapor clouds, the distribution of lethal concentrations, and the probability of death from a toluene leak from a height of 6 m of the tank wall. The outputs of the two modeling programs were analyzed and compared. The results showed that the maximum threat zone distances associated with high hazards of toxicity, flammability, and thermal radiation of toluene were respectively 736, 132, and 52 m in ALOHA and 1626, no result, and 239 m for PHAST from the accident point in the downwind. The highest probability of death was 92%, which occurred at a distance of 1 m in the cold seasons. The output values for the PHAST program were higher than those for ALOHA. The results also showed that the survival zone in which the probability of death was low could be determined from a distance of 51 m onwards. Although the assessment of the results indicated no matching between the results obtained by ALOHA and PHAST, the program outputs could still help decision-makers in emergency response planning and the allocation of medical and support services during emergencies.
Afficher plus [+] Moins [-]Yard waste prediction from estimated municipal solid waste using the grey theory to achieve a zero-waste strategy Texte intégral
2022
Islam, Md. Rakibul | Kabir, Golam | Ng, Kelvin Tsun Wai | Ali, Syed Mithun
Yard waste is one of the key components of municipal solid waste and can play a vital role in implementing zero-waste strategy to achieve sustainable municipal solid waste management. Therefore, the objective of this study is to predict yard waste generation using the grey theory from the predicted municipal solid waste generation. The proposed model is implemented using municipal solid waste generation data from the City of Winnipeg, Canada. To identify the generation factors that influence municipal solid waste generation and yard waste generation, a correlation analysis is performed among eight socio-economic factors and six climatic factors. The GM (1, 1) model is utilized to predict individual factors with overall MAPE values of 0.06%−10.39% for the in-sample data, while the multivariable GM (1, N) grey model is employed to forecast the quarterly level of municipal solid waste generation with overall MAPE values of 5.64%−7.54%. In this study, grey models predict quarterly yard waste generation from the predicted municipal solid waste generation values using only twelve historical data points. The results indicate that the grey model (based on the error matrices) performs better than the linear and nonlinear regression-based models. The outcome of this study will support the City of Winnipeg’s sustainable planning for yard waste management in terms of budgeting, resource allocation, and estimating energy generation.
Afficher plus [+] Moins [-]Effect of gervital in attenuating hepatotoxicity caused by methotrexate or azathioprine in adult albino rats Texte intégral
2022
Abdul-Hamid, Manal | Abdel-Reheim, Eman Salah | Hegazy, Walaa | Allam, Ahmed | Othman, Sarah I. | Alwaele, Maha Abdulla | Abdel-Kawi, Samraa Hussein
Methotrexate (MTX) and azathioprine (AZA) are chemotherapeutic, antimetabolic, and immunosuppressive agents with substantial risks such as oxidative lesions to the liver. This study examined the effect of grape seed extract (GSE; gervital) in attenuating hepatotoxicity caused by MTX or AZA treatment. Rats were divided into six groups (six rats per group): Group I, normal control group; Group II, GSE (150 mg/kg/day); Group III, MTX (8 mg/kg/week); Group IV, AZA (15 mg/kg/day); Group V, GSE (150 mg/kg/day) + MTX (8 mg/kg/week); and Group VI, GSE (150 mg/kg/day) + AZA (15 mg/kg/day). After 35-day experimental period, all rats were sacrificed and blood was collected for biochemical study and hemoglobin (Hb) assessment. The liver was weighed and triaged for histological, ultrastructural, and biochemical studies. MTX and AZA treatment decreased Hb levels, increased relative liver weight, increased the activity of glutamate pyruvate transaminase (ALT) and glutamate oxaloacetate transaminase (AST) aminotransferase (ALT) and aspartate aminotransferase (AST) values, and displayed histopathological and ultrastructural alterations. These changes included the disorganization of hepatocytes, pyknosis, karyolysis of some nuclei, and mononuclear leukocytic infiltration. The liver with significant oxidative stress (OS) showed decreased reduced glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD) and increased malondialdehyde (MDA) levels. In contrast, GSE administration ameliorated ALT, AST, and all histopathological and ultrastructural changes. GSE treatment also reduced MDA levels but increased the antioxidant parameters. In conclusion, it was concluded that GSE supplementation could be considered as a promising antioxidant in reducing OS, histopathological and ultrastructural alterations induced by MTX and AZA.
Afficher plus [+] Moins [-]Energy performance of European countries by considering the role of forest Texte intégral
2022
Lu, Liang Chun | Chiu, Shih-Yung | Chiu, Yung-Ho | Chang, Tzu-Han | Tang, William
This paper applies the modified undesirable dynamic data envelopment analysis (DEA) model by considering the role of forest carbon sinks to evaluate European countries’ carbon dioxide (CO₂) emissions and productivity efficiency. Taking population and energy consumption as input variables, gross domestic product (GDP) as the desirable input, CO₂ as the undesirable output, and fixed assets as an inter-temporal carry-out input variable, our results suggest considering the fixed amount of the forest carbon sinks significantly affects efficiency rankings. The overall efficiency rankings for Ireland, Austria, Italy, Germany, Spain, and Belgium look to be overrated, while those of Finland, France, and Netherlands are apparently underrated. In terms of Total-Factor Efficiency analysis, countries with the best performance in efficiency ranking are Denmark, Luxembourg, Norway, Sweden, and the UK, thanks to their long-term effort at addressing the impact of forest carbon sinks and the effect of CO₂ emissions on efficiency.
Afficher plus [+] Moins [-]Ganga river water quality assessment using combined approaches: physico-chemical parameters and cyanobacterial toxicity detection with special reference to microcystins and molecular characterization of microcystin synthetase (mcy) genes carrying cyanobacteria Texte intégral
2022
Kesari, Vigya | Kumar, Sanjay | Yadav, Indrajeet | Chatterjee, Antra | Rai, Shweta | Pandey, Shraddha
Water quality assessment relies mostly on physico-chemical-based characterization; however, eutrophication and climate change advocate the abundance of toxic microcystins (MCs) producing cyanobacteria as emerging bio-indicator. In the present study, a spatial-temporal analysis was carried out at ten sampling sites of Prayagraj and Varanasi during June 2017 and March 2018 to determine the Ganga River water quality using physico-chemical parameters, cyanobacteria diversity, detection of MCs producing strains and MC-LR equivalence. Coliform bacteria, COD, NO₃-N, and phosphate are the significant contaminated parameters favoring the growth of putative MCs producing cyanobacteria. National Sanitation Foundation WQI (NSFWQI) indicates water quality, either bad or medium category at sampling points. The morphological analysis confirms the occurrence of diverse cyanobacterial genera such as Microcystis, Anabaena, Oscillatoria, and Phormidium. PCR amplification affirmed the presence of toxic microcystin (mcy) genes in uncultured cyanobacteria at all the sampling sites. The concentration of MC-LR equivalence in water samples by protein phosphatase 1 inhibition assay (PPIA) and high-performance liquid chromatography (HPLC) methods was observed in the range of 23.4–172 ng/L and 13.2–97.5 ng/L respectively which is lower than the harmful exposure limit by World Health Organization (WHO). Ganga isolate 1 was identified as Microcystis based on partial 16S rDNA sequence and its toxicity was confirmed due to presence of mcy genes and MCs production potential. These findings suggest the presence of MCs producers as new emerging parameter to monitor water quality index and identification up to species level will be valuable for restoration strategies of river Ganga.
Afficher plus [+] Moins [-]A reference material (NMIJ RM 4076-a) for the determination of short-chain chlorinated paraffins Texte intégral
2022
Hanari, Nobuyasu | Aoyagi, Yoshie | Orihara, Yukari
Chlorinated paraffins are primary industrial chemical products used for metalworking fluids and flame retardants. However, short-chain chlorinated paraffins (SCCPs) are registered in Annex A of the Stockholm Convention on Persistent Organic Pollutants. Therefore, since an accurate quantitative determination of SCCPs is crucial to monitor the level of pollution, analysis quality assurance with reference materials is needed. In this study, a reference material (RM), NMIJ RM 4076-a, was developed by the National Metrology Institute of Japan at the National Institute of Advanced Industrial Science and Technology (NMIJ/AIST) for the quantification of SCCPs. We determined the mass fraction of SCCPs by subtracting the impurities quantified using the mass-balance method, a combination of gas chromatography-flame ionization detection, Karl Fischer titrations, headspace-gas chromatography-mass spectrometry, and thermal gravimetric analysis. The mass fraction value of NMIJ RM 4076-a was concluded to be 0.9996 kg/kg. The standard uncertainty of this mass fraction was evaluated on the basis of the mass-balance method, the sample homogeneity, and stability obtained using the above analytical techniques. Accordingly, the expanded uncertainty estimated using a coverage factor of k = 2 was found to be 0.0013 kg/kg. The mass fraction of chlorine and the homologue compositional ratios are also given for this RM as supplementary technical information. This RM is expected to be applicable for use in the calibration of instruments, or for checking the validity of analytical methods or instruments for estimating the comparability of SCCP analyses.
Afficher plus [+] Moins [-]Method of manufacturing and staining microplastics for using in the biological experiments Texte intégral
2022
Le Quoc, Pham | Fokina, Maria I. | Martynova, Daria M. | Olekhnovich, Roman O. | Uspenskaya, Mayya V.
Nowadays, plastic pollution attracts much attention both from society and scientists. The plastic pollution impact on the environment and human health requires assessment urgently, especially through experimental studies. However, such studies are still scarce because of the lack of standard methods for assessing their effects on living organisms. We have developed a process for manufacturing and staining PVC microparticles for using them in biological and ecological experiments. The electrospinning method has been used to manufacture PVC particles; their morphology and size have been analyzed. The obtained PVC particles are of narrow size range averaging 2–4 µm in diameter. They are successfully stained with the fluorescent dye Rhodamine B, which stands for the experiments performed in the seawater.
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