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Water planning in a mixed land use Mediterranean area: point-source abstraction and pollution scenarios by a numerical model of varying stream-aquifer regime
2019
Du, Mingxuan | Fouché, Olivier | Zavattero, Elodie | Ma, Qiang | Delestre, Olivier | Gourbesville, Philippe
Integrated hydrodynamic modelling is an efficient approach for making semi-quantitative scenarios reliable enough for groundwater management, provided that the numerical simulations are from a validated model. The model set-up, however, involves many inputs due to the complexity of both the hydrological system and the land use. The case study of a Mediterranean alluvial unconfined aquifer in the lower Var valley (Southern France) is useful to test a method to estimate lacking data on water abstraction by small farms in urban context. With this estimation of the undocumented pumping volumes, and after calibration of the exchange parameters of the stream-aquifer system with the help of a river model, the groundwater flow model shows a high goodness of fit with the measured potentiometric levels. The consistency between simulated results and real behaviour of the system, with regard to the observed effects of lowering weirs and previously published hydrochemistry data, confirms reliability of the groundwater flow model. On the other hand, accuracy of the transport model output may be influenced by many parameters, many of which are not derived from field measurements. In this case study, for which river-aquifer feeding is the main control, the partition coefficient between direct recharge and runoff does not show a significant effect on the transport model output, and therefore, uncertainty of the hydrological terms such as evapotranspiration and runoff is not a first-rank issue to the pollution propagation. The simulation of pollution scenarios with the model returns expected pessimistic outputs, with regard to hazard management. The model is now ready to be used in a decision support system by the local water supply managers.
显示更多 [+] 显示较少 [-]The association between iron, calcium, and oxidative stress in seminal plasma and sperm quality
2019
Ammar, Oumaima | Houas, Zohra | Mehdi, Meriem
The present study aimed to determine the level of iron and calcium in the seminal plasma of men with different fertility potentials and to examine its relationship with oxidative stress. Seventy-nine sub-fertile patients with asthenoteratozoospermia (AT), n 27; teratoleucozoospermia (TL), n 20; teratozoospermia (Terato), n 32; and 29 healthy donors were included. The ability of spermatozoa to produce reactive oxygen species (ROS) was evaluated by using nitroblue tetrazolium (NBT) staining. The lipid peroxidation end product, malondialdehyde (MDA), and the trace element levels (iron and calcium) were measured spectrophotometrically. Iron and calcium concentrations in seminal plasma of the patient groups were significantly more elevated than the normal group. Nevertheless, both calcium and iron showed strong negative correlations with the total sperm motility and normal sperm morphology, but only iron was positively and significantly associated with multiple anomalies index and seminal leucocyte concentration. On the other hand, the rates of MDA and ROS production in semen were significantly higher in the three abnormal groups than in controls. These two oxidative stress biomarkers were significantly associated with the percentage of atypical forms in semen. However, only semen ROS level was significantly associated with the decreased sperm motility and the sperm leucocytes concentration. Meanwhile, there are positive correlations between seminal iron and calcium content and the studied oxidative stress biomarkers. Oxidative stress and trace element excess are implicated in low sperm quality. Iron and calcium might be the mediators of the effects of oxidative damage and induces lipid peroxidation.
显示更多 [+] 显示较少 [-]Optimisation, experimental validation and thermodynamic study of the sequential oil extraction and biodiesel production processes from seeds of Sterculia foetida
2019
Sambasivam, Kavitha Muniswamy | Murugavelh, Somasundaram
Non-edible seeds are not used in any commercial applications, which implies that they can be used for biofuel applications. The present study aimed to maximise the process conditions for oil extraction and sterculia biodiesel production from Sterculia foetida (poon oil). GC-MS identified the methyl esters of sterculia oil as sterculic acid (32%), palmitic acid (15.88%), oleic acid (10.00%), linoleic acid (9.95%) and malvalic acid (9%). Response surface methodology (RSM) based parametric optimisation of oil extraction was carried out by choosing process variables such as sample weight, volume of solvent to seed ratio and time. The optimum sample amount of 7.5 g and the volume of solvent to seed ratio of 40 mL/g resulted in a maximum oil yield of 45.27% at 3 h. The results were statistically significant (P < 0.05) with a regression coefficient (R²) of 0.9988. Furthermore, the artificial neural network (ANN) resulted in an R² value greater than 0.9, which validates the RSM. Conventional optimisation of the temperature (55 °C), feedstock to methanol ratio (1:12), catalyst proportion (1.5%) and transesterification reaction time (60 min) yield 90.87% biodiesel production. The physicochemical characteristics of oil and biodiesel complied with the requirements of the ASTM standards. The rate constant and thermodynamic variables at the optimum temperature (333 K) were calculated from the experimental data. The activation energy (Eₐ), activation enthalpy in transition state theory (ΔH⁺⁺), activation entropy in transition state theory (ΔS⁺⁺) and Gibbs free energy in transition state theory (ΔG⁺⁺) were 37.91 kJ mol⁻¹, 35.14 kJ mol⁻¹, − 239.58 J mol⁻¹ K⁻¹ and 79.81 kJ mol⁻¹ respectively. Graphical abstract
显示更多 [+] 显示较少 [-]Attitudes to climate change, perceptions of disaster risk, and mitigation and adaptation behavior in Yunlin County, Taiwan
2019
Lee, Yung-Jaan | Tung, Chuan-Ming | Lin, Shih-Chien
Issues that are associated with climate change have global importance. Most related studies take a national or regional perspective on the impact of climate change. Taiwan is constrained by its geographical conditions, which increase its vulnerability to climate change, especially in its western coastal areas. The county that is most affected by climate change is Yunlin. In 2013–2014, projects that were sponsored by Taiwan’s government analyzed the relationship among synthesized vulnerability, ecological footprint (EF) and adaptation to climate change and proposed 15 categories of synthesized vulnerability and EF values. This study further examines the relationship between vulnerability and EF values and examines how residents of four townships—Linnei, Sihu, Mailiao, and Huwei—cope with the effects of climate change. This study investigates whether the residents of the four townships vary in their attitudes to climate change, their perceptions of disaster risk, and their behavioral intentions with respect to coping with climate change. The structural equation model (SEM) is used to examine the relationships among attitudes to climate change, perceptions of disaster risk, and the behavioral intentions of residents in townships with various vulnerabilities to climate change. The results that are obtained using the SEM reveal that climate change mitigation/adaptation behavior is affected by attitudes to climate change and perceptions of disaster risk. However, the effects of attitudes and perceptions on mitigation and adaptation that are mediated by place attachment are not statistically significant.
显示更多 [+] 显示较少 [-]Thermotolerance of camel (Camelus dromedarius) somatic cells affected by the cell type and the dissociation method
2019
Saadeldin, Islam M. | Swelum, Ayman Abdel-Aziz | Tukur, Hammed A. | Alowaimer, Abdullah N.
Researchers dealing with heat stress experiments use different cell kinds and use trypsin that has been reported to affect the cellular proteins of cultured cells. Therefore, we compared the effects of acute and chronic exposures to high temperature (45 °C) on camel skin fibroblast and granulosa cells. Primary culture of fibroblasts and granulosa cells tolerated the acute heat shock for 2 h; however, granulosa cells cultured for long duration (20 h) showed thermotolerance when compared with the fibroblasts. Moreover, the effect of cell dispersion method (trypsin and mechanical dissociation) on the thermotolerance of sub-cultured cells was examined. Trypsin altered the morphology of fibroblasts and granulosa cells exposed to 45 °C for 4 h. Moreover, trypsin significantly reduced the fibroblast and granulosa cell migration in the wound healing assay. The current results demonstrate that cell passaging and cell type can affect the thermotolerance of the cells; it also revealed that trypsin could alter the cellular response to the heat shock. We raise the demand for another alternative method for cell dispersion in experiments dealing with cellular responses to the heat shock.
显示更多 [+] 显示较少 [-]Health risk assessment through determining bioaccumulation of iron in forages grown in soil irrigated with city effluent
2019
K̲h̲ān̲, Ẓafar Iqbāl | Safdar, Hareem | Kafīl, Aḥmad | Wajid, Kinza | Bashir, Humayun | Ugulu, Ilker | Dogan, Yunus
The irrigation with sewage water can be useful if it has no negative effects on food crop yield, soil pollution, and health of humans. However, it includes various types of contaminants like heavy metals that pollute the soil and crops. In this regard, the aim of this study was to evaluate the possible health risks of heavy metals in forages. Forages both of summer and winter were grown with different water treatments (sewage water and tap water) in Department of Botany, University of Sargodha. The concentration of iron (Fe) in water, soil, and plant samples was determined. The Fe values in tap and sewage water were observed as 0.090 and 0.115 mg/L, respectively. The highest mean concentration of Fe was 9.608 mg/kg in the soil where Trifolium alexandrinum is grown, and the lowest mean concentration was 0.154 mg/kg which occurred in the soil where Trifolium resupinatum is grown in winter. The maximum mean concentration of Fe in the root samples of plants was observed as 2.483 mg/kg in Pennisetum typhoideum, and the minimum mean concentration occurred as 0.390 mg/kg in Zea mays grown in summer. The maximum bioconcentration factor value of Fe was observed for T. resupinatum (5.259) grown in winter. The maximum pollution load index value of Fe was observed for T. alexandrinum (0.1688). The maximum value of daily intake of metals was observed as 0.0731 in Medicago sativa, and the maximum health risk index value was determined as 0.1091 in P. typhoideum.
显示更多 [+] 显示较少 [-]Levels and health risk assessments of particulate matters (PM2.5 and PM10) in indoor/outdoor air of waterpipe cafés in Tehran, Iran
2019
Heydari, Gholamreza | Taghizdeh, Farhad | Fazlzadeh, Mehdi | Jafari, Ahmad Jonidi | Asadgol, Zahra | Mehrizi, Ehsan Abouee | Moradi, Masoud | Arfaeinia, Hossein
To determine the concentration of particulate matters (PM₂.₅ and PM₁₀), 36 samples were collected from indoor/outdoor air of hookah cafés (HS), cigarette cafés (CS), both hookah and cigarette (HCS), and no-smoking building (NS) in Tehran City from December 2017 to March 2018. The mean ± SD of PM₁₀ concentration in the indoor air of the cafés in terms of HS, CS, HCS, and NS sites has been 702.35, 220.20, 1156.60, and 60.12 μg/m³, while for PM₂.₅, the values have been 271.92, 111.80, 619.10, and 22.25 μg/m³, respectively. It was also found that the PM concentration inside the cafés was higher during weekend session (with a higher number of active smokers), than during the weekday sessions. Moreover, the PM levels in the indoor air of the cafés were considerably higher than those of the outdoors (p < 0.05). Based on path analysis, the number of “active smokers” had the highest influence on production of PM inside the cafés, followed by the tobacco type. Finally, the mean excess lifetime cancer risk (ELCR) for PM₂.₅ in the indoor air of cafés was observed in the range of 0.64 × 10⁻⁵–14.98 × 10⁻⁵. Also, the mean of hazard quotient (HQ) for PM2.5 and PM₁₀ was calculated in range of 0.82–18.4 and 0.16–3.28, respectively, which corresponds to an unacceptably high risk for human health. The PM levels in the indoor air of smoking cafés in Tehran are significantly high, such that it can cause serious risks for the health of both the customers and personnel. Thus, it is necessary that suitable controlling strategies be adopted for this public health threat.
显示更多 [+] 显示较少 [-]The nexus of renewable and nonrenewable energy consumption, trade openness, and CO2 emissions in the framework of EKC: evidence from emerging economies
2019
Zafar, Muhammad Wasif | Mirza, Faisal Mehmood | Zaidi, Syed Anees Haider | Hou, Fujun
Emerging economies are experiencing considerable economic changes due to change in energy demand and CO₂ emissions. To explore the link between energy demand and CO₂ emissions, this study disaggregates energy consumption into renewable and nonrenewable, and investigates its impact on carbon (CO₂) emissions by incorporating the role of trade openness using the environment Kuznets curve (EKC) framework. Emerging economies from 1990 to 2015 are examined based on Morgan Stanley Capital International’s (MSCI’s) classification. This empirical study uses cross-sectional dependence (CD) test and second-generation panel unit root test for precise estimation. The Pedroni and Westerlund panel cointegration tests are used to examine the long-run equilibrium. Continuously updated fully modified (CUP-FM) and continuously updated bias-corrected (CUP-BC) approaches are applied to investigate long-run output elasticities while the vector error correction model (VECM) is used to examine the direction of causal relationships among the variables. The results show that renewable energy consumption affects the CO₂ emissions negatively while nonrenewable energy consumption positively impacts the CO₂ emissions. The study also supports the EKC hypothesis. Trade openness adversely affects the CO₂ emissions which are an imperative inclination of these economies towards globalization. Moreover, in the long run, energy consumption from renewable energy and economic growth Granger cause CO₂ emission, nonrenewable energy, and trade openness. In the short run, renewable energy Granger causes economic growth, while economic growth Granger causes nonrenewable energy. The study offers some vital policy suggestions for these emerging economies and some interesting lessons for the developing economies.
显示更多 [+] 显示较少 [-]Biochar can improve the soil quality of new creation farmland on the Loess Plateau
2019
Su, Cui-Cui | Ma, Ji-Fu | Chen, Yiping
The Loess Plateau is the most severely degraded soil area worldwide and represents one of the lowest areas of soil productivity. To solve the conundrum between increasing populations and decreasing agricultural acreage, enhancing the quantity of cultivated land, gully land consolidation projects has been implemented. However, the new creation farmland soil is not enough to satisfy the demand of agricultural production. An incubation experiment was conducted to determine the effects of biochar on the new creation farmland soil. Five levels of amendments (0, 1%, 2%, 5%, and 10% (wt%) biochar soil) were used, and the soil columns remained in the laboratory for approximately 2 months. The results show that biochar proportion was a more important factor than incubation time across all soils tested. The soil moisture content and particle size clearly increased as the amendment level increased; however, the soil pH decreased gradually with incubation time and tended to slow soil salinization. These findings will have to be verified under field conditions.
显示更多 [+] 显示较少 [-]Giardia spp. and Cryptosporidium spp. removal efficiency of a combined fixed-film system treating domestic wastewater receiving hospital effluent
2019
Yamashiro, Sandra | Foco, Mário Luiz Rodrigues | Pineda, Carolina Ortiz | José, Juliana | Nour, Edson Aparecido Abdul | Siqueira-Castro, Isabel Cristina Vidal | Franco, Regina Maura Bueno
Giardia and Cryptosporidium have caused numerous outbreaks of diarrhea as a result of the ingestion of water contaminated with sewage. In Brazil, the efficiency of Giardia and Cryptosporidium removal by combined fixed-film systems has rarely been studied. The aims of the present study were therefore to verify the removal efficiency of Giardia and Cryptosporidium by a combined system (anaerobic/anoxic filter and aerated submerged biofilter) and to perform the genetic characterization of these parasites. The (oo)cysts were detected by centrifuge concentration and membrane filtration from raw sewage, effluents, adhered biomass, and sludge samples. Immunofluorescence assay and differential interference contrast microscopy were used for the visualization of the (oo)cysts. Nested PCR was applied to confirm Giardia and Cryptosporidium. Giardia and Cryptosporidium were detected in 27% and 5.5% of the 144 analyzed samples of raw sewage and effluents, respectively. A total of 33,000 cysts/L were recovered in the adhered biomass samples (n = 25) from different points of the aerated submerged biofilter, while 6000 oocysts/L were registered in a single point. An average of 11,800 cysts/L were found in the sludge samples (n = 5). The combined system exhibited a removal efficiency of Giardia cysts of 1.8 ± 1.0 log removal. The C and BIV assemblages of Giardia were identified in the raw sewage while AII was found in the treated effluent sample. It was not possible to calculate the removal efficiency of Cryptosporidium oocysts by the combined system. The combined system exhibited some potential as a suitable treatment for the removal of parasites from sewage.
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