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Ameliorative effect of kefir against γ-irradiation induced liver injury in male rats: impact on oxidative stress and inflammation
2020
Ali, Ola Sayed M. | Amin, Nour El-Din | Abdel Fattah, Salma M. | Abd El-Rahman, Omnia
Ionizing radiation is a double-edged sword because of its benefits and risks to human health. Therefore, protecting human organs from harmful effects of radiation is an important concern of researchers. Kefir, as a good source of probiotics, received growing interest in protective medicine owing to its antioxidant, anti-inflammatory, and immunomodulatory properties. Thus, this study was planned to investigate the protective role of kefir against γ-radiation-induced hepatotoxicity. Thirty-two male rats were distributed in four groups: (I) control, (II) received Kefir orally (5 ml/kg body weight) for 28 days, (III) exposed to whole body γ-irradiation (6.5 Gy) to induce hepatotoxicity, and (IV) was pretreated with kefir for 21 days then exposed to γ-irradiation followed by 7 days of kefir treatment. At the end of the experiment, complete blood picture (CBC), liver function, and lipid profile were estimated. Furthermore, levels of lipid peroxidation, nitric oxide content, and endogenous antioxidants, in addition to concentrations of copper, iron, and calcium were measured in liver tissue. Furthermore, monocyte chemoattractant protein-1 (MCP-1) and relative gene expression of nuclear factor kappa (NF-κB) were assessed. The results revealed that oral administration of kefir significantly reduced the radiation-induced hepatic histological alterations, hepatic function impairment, and dyslipidemia. Moreover, kefir notably ameliorated the state of oxidative stress and appeared to inhibit the induced inflammation. This study provides a possible counteracting role of kefir against hepatotoxicity induced γ-radiation. This can focus the benefit of kefir application as a prophylactic treatment to limit hepatic inflammation during radiotherapy.
Afficher plus [+] Moins [-]The Effects of the Commercially Formulated Neonicotinoids Imidacloprid and Thiamethoxam on the Survival of Infectious Stages of Two Trematode Parasites
2020
Rohonczy, Jillian L. M. | Koprivnikar, Janet | Waltho, Nigel | Robinson, Stacey A.
Neonicotinoids are a popular class of systemic insecticides registered for use in over 120 countries. Recent global water surveys have found neonicotinoid insecticides in waterbodies adjacent to agricultural fields. The presence of neonicotinoids in surface waters raises the concern of the potential risk of exposure to non-target aquatic species, with relevance for both free-living and parasitic taxa. The susceptibility of aquatic free-living parasitic stages to the lethal effects of neonicotinoids may influence the prevalence and intensity of host infection, and their availability as prey for a variety of organisms (e.g., fish, invertebrates). We examined the effects of two commonly used neonicotinoids on the survival of free-living infectious stages (cercariae) from two trematode (flatworm) species (Diplostomum sp. and Haematoloechus sp.). We found that exposure to commercially formulated imidacloprid and thiamethoxam, individually and in a binary mixture, had no significant effect on cercarial survival for either species at environmentally relevant concentrations. Further study is required to understand if the ability of the surviving cercariae to infect the next host in their life cycle is compromised in the presence of neonicotinoids, or if host defenses are compromised, as changes in parasite infectivity or host susceptibility could influence infection dynamics and have community- and ecosystem-level implications.
Afficher plus [+] Moins [-]Initial Geochemical Study of Planned Impact Zones of the Separated Parts of Launch Vehicles by OneWeb Project (Inclination 87°, Russia)
2020
Saltykov, Aleksey V. | Balykin, Sergey N. | Archipov, Igor A. | Puzanov, Aleksandr V.
The results in the article have both practical and scientific significance. The practical significance is due to the need to determine the parameters of the initial condition of natural landscapes in the impact zones (IZ) of the separated parts of launch vehicles, which will be used to identify changes in the process of their operation. Scientific significance is associated with the low knowledge of the studied landscapes, because of their inaccessibility. The main components of the landscape, which may be adversely affected by space rocket activity (surface water, snow cover, plants, and soils), were used as the objects of the study. Samples were taken in three stages: autumn, winter, and summer-autumn. During the autumn stage, water samples were taken; during the winter, snow samples; and during the summer-autumn, water, soil, and plant samples. Acidity (pH), chemical oxygen demand (COD), hydrocarbons, and ionic composition were determined in water and snow samples; pH, hydrocarbons and total organic carbon, elemental composition, and cation exchange capacity (CEC) were determined in soil samples; elemental composition was determined in plant samples. During the autumn low-water season, the chemical properties of water in all rivers did not differ significantly, except for Junguele river, which had a lower acidity and more intense chemical oxygen demand, as well as a higher concentration of Mg²⁺ and K⁺ ions. In the winter stage, it was revealed that the snow cover of all planned IZ will turn into slightly acidic or neutral waters with a slight concentration of hydrocarbons, NO₃⁻, Mg²⁺, Zn²⁺, Mn²⁺, and Al³⁺, the distribution of which is uniform within the boundaries of each IZ. During the summer-autumn stage, despite the flood, no significant changes in the chemical composition of water in the studied rivers were detected.
Afficher plus [+] Moins [-]Environmental evaluation and optimization of energy use and greenhouse gases mitigation for farm production systems in Mashhad, Iran
2020
Taleghani, Abolfazl | Almassi, Morteza | Ghahderijani, Mohammad
The current paper aimed at evaluating and optimizing the efficiency of energy use and mitigation of environmental pollution by minimizing the emissions and intensity of greenhouse gases (GHG) for farm production systems in Mashhad, Iran. The results indicated that the total values of consumed energy were equal to 28,648, 38,479, and 43,490 MJha⁻¹ for barley, canola, and forage corn, respectively. The highest rate of the consumed energy for all crops belonged to irrigation electricity, diesel fuel, and nitrogen consumption. The highest and lowest energy efficiencies were respectively achieved from forage corn and canola, while barley production led to the lowest GHG emissions. The estimation of GHG intensity demonstrated that canola with 53% took up the highest intensity, which was followed by barley (30%) and forage corn (17%). Since the intensity of GHG takes into account the amount of energy produced by each crop per hectare, this index is more suitable than GHG emissions for assessing environmental pollution. The results of optimal responses of the multiple goal programming (MGP) model revealed that the optimum evaluated cultivation areas (for meeting the goals of the study) for barley and forage corn were 10,088 and 3256 ha, respectively, while the MGP model generally eliminates canola from the cultivation plan. On the other hand, the plan proposed by the MGP model increases the total energy efficiency from 103,625 for the current systems to 105,169 for the optimized systems per year. Furthermore, the emissions and intensity of GHG were reduced by the model to 311,786 kgCO₂eq and 10 kgCO₂eq MJoutput⁻¹ per year, respectively.
Afficher plus [+] Moins [-]Multivariate assessment of atmospheric deposition studies in Bulgaria based on moss biomonitors: trends between the 2005/2006 and 2015/2016 surveys
2020
Hristozova, Gergana | Marinova, Savka | Motyka, Oldřich | Svozilík, Vladislav | Zinicovscaia, Inga
This study aims to investigate the changes in atmospheric deposition trends in Bulgaria, studied using the moss biomonitoring technique since 1995. For the first time, a paired (site-wise) comparison was performed after a critical review of the sampling networks and adjusting for location, the distance between the sampling points, and moss species. Data from the 2005/2006 and 2015/2016 moss surveys were chosen as instrumental neutron activation analysis was employed in both to determine the content of 34 elements (Al, As, Ba, Br, Са, Ce, Cl, Со, Cr, Cs, Fe, Hf, I, K, La, Mn, Na, Nd, Ni, Rb, Sb, Sc, Se, Sr, Ta, Tb, Th, Ti, Tm, U, V, W, Yb, Zn). In addition, Cd, Cu, and Pb were determined using complementary analytical methods: inductively coupled plasma atomic emission spectroscopy in 2015/2016 and atomic absorption spectroscopy in 2005/2006. For the subset of 57 routinely sampled locations in Bulgaria, hierarchical clustering on principal components and multiple factor analysis (MFA) were applied to assess the spatial trends in the 10 years elapsed between the surveys, as well as to characterise the origin of the determined elements. Elevation and distance between the sampling points were used as additional variables in the multiple factor analysis plane to ascertain their effect on the overall variance in the datasets. Distribution maps were constructed to illustrate the deposition patterns for the pollutant Pb. The results were consistent with decreased industrial output in the country, increased coal combustion and transport pollution, and construction of roads.
Afficher plus [+] Moins [-]Natural Removal of Crude and Heavy Fuel Oil on Rocky Shorelines in Arctic Climate Regimes
2020
Gustavson, Kim | Hansson, Sophia V. | van Beest, Floris M. | Fritt-Rasmussen, Janne | Lassen, Pia | Geertz-Hansen, Ole | Wegeberg, Susse
Facilitated by a receding sea ice extent, new and shorter routes have led to increased maritime traffic in Arctic areas with an inherent risk for oil spills along Arctic rocky shorelines. To estimate natural oil removal under Arctic conditions, a crude oil and a heavy fuel oil were applied to slate tiles, mimicking rocky shore substratum, and placed at four levels within and just above the tidal zone on two rocky shorelines in West Greenland. Tiles were regularly sampled (within 95 days) to determine natural oil removal and chemical composition of the remaining oil. We found that natural oil removal on the rocky shorelines depends on (1) level position on the shoreline, i.e., within and above the tidal zone where ample exposure to water and wave-wash increases oil removal rate and efficiency, and (2) physical and chemical oil properties with the crude oil being removed more readily than the heavy fuel oil. These findings can help improve the risk assessment of oil spills in Arctic areas and facilitate the development of effective oil spill response strategies in Arctic seas.
Afficher plus [+] Moins [-]Assessment of background levels and pollution sources for arsenic and fluoride in the phreatic and confined groundwater of Xi’an city, Shaanxi, China
2020
Gao, Yanyan | Qian, Hui | Wang, Haike | Chen, Jie | Ren, Wenhao | Yang, Faxuan
The presence of arsenic and fluoride in groundwater and their impacts on human health have been reported in many countries worldwide, but little information is available on As or F⁻ contamination in Xi’an city. This study highlights the distribution and sources of As and F⁻ anomalies in different aquifers of Xi’an city, based on the assessment of natural background levels (NBLs) and threshold values (TVs). Groundwater samples collected from phreatic and confined aquifers were analyzed to evaluate NBLs and TVs, using median + 2MAD, Tukey inner fence (TIF), and percentile-based methods. Results showed that NBLs and TVs of As and F⁻ in the phreatic aquifer were lower than those in the confined aquifer, indicating importance of the geological effects on the enrichment of arsenic and fluoride in the confined aquifer. Combined with hydrogeochemical methods, the distributions of As and F⁻ anomalies show that high concentrations of As in both aquifers and F⁻ in the confined aquifer can be attributed to the upward flow of geothermal water through faults and ground fissures, while high concentrations of F⁻ in the phreatic aquifer may be greatly influenced by contaminated rivers. Although geological structures such as faults and ground fissures contribute to the high concentrations of potentially toxic elements, anthropogenic activities cannot be ignored because over exploitation of groundwater accelerates the development of ground fissures and results in the upward flow and mixing of geothermal water with groundwater in the upper aquifers.
Afficher plus [+] Moins [-]Insights into fouling behavior in a novel anammox self-forming dynamic membrane bioreactor by the fluorescence EEM-PARAFAC analysis
2020
Zhu, Yijing | Cao, Lijuan | Ni, Lingfeng | Wang, Yayi
Fouling behavior of the novel anaerobic ammonium oxidation (anammox) self-forming dynamic membrane bioreactor (SFDMBR) was elucidated, which is using nylon mesh as the filter with controlled fouling and successful anammox process. Properties of anammox sludge and foulants in the anammox SFDMBR and MBR (using PVDF microfiltration membrane) were compared to analyze the alleviated fouling in the SFDMBR, of which transmembrane pressure could be kept below 10 kPa for 50 days in one filtration cycle of 82 days with flux of 12 L m⁻² h⁻¹. Colorimetrical determination and excitation emission matrices-parallel factor (EEM-PARAFAC) analysis of the foulants showed that humic acid content in foulants on nylon mesh was obviously lower than that on PVDF membrane. Considering that the small-sized and flexible humic acids prefer to plug into membrane pores, the alleviated irreversible fouling in the SFDMBR could be attributed to the less microbial humic acid content of foulants (8.8 ± 1.0%) compared with the MBR (20.7 ± 2.9%). The adequate efflux of humic-like substances in the operation with nylon mesh was speculated to be the main mechanism of fouling control in the SFDMBR. These findings highlighted the potential of anammox SFDMBR in practical applications, because of the high humic acid contents in real ammonium-laden wastewater. Our study highlights the important role of humic acids in fouling behavior of the novel anammox SFDMBR to provide guidance for fouling control strategies. Graphical abstract
Afficher plus [+] Moins [-]Enhanced uptake of Cd, Cr, and Cu in Catharanthus roseus (L.) G.Don by Bacillus cereus: application of moss and compost to reduce metal availability
2020
Mushtaq, Muhammad Umair | Iqbal, Ameena | Nawaz, Ismat | Mirza, Cyrus Raza | Yousaf, Sohail | Farooq, Ghazanfar | Ali, Muhammad Arif | Khan, Aqib Hassan Ali | Iqbal, Mazhar
Heavy metals (HMs) being the notorious and toxic are being introduced into the environment credited to natural and anthropogenic activities. The use of ornamental plants is being ignored as potential candidates for HMs phytoremediation. In this study, pot experiments were conducted on Catharanthus roseus (L.) G.Don to evaluate selected heavy metals tolerance and accumulation potential with reference to the bacterial endophyte (Bacillus cereus) and organic amendments (moss and compost at 5% v/v). Results indicated improvement in uptake of Cd (230 mg kg⁻¹), Cu (229 mg kg⁻¹), and Cr (458 mg kg⁻¹) by C. roseus with B. cereus. The concentration of Ni and Pb was found highest in controls (without strain) that were 420 and 904 mg kg⁻¹, respectively. Conversely, the addition of organic amendments enhanced biomass production, as compared to controls, 441, 471, and 763% by peat moss (T3), compost (T4), and peat moss + compost + inoculum treatments (T6), respectively, while reduction of plant HMs content was observed. Microbial-aided phytoremediation/phytoextraction could be a potential method for removal of Cd, Cr, and Cu, while organic amendments can significantly improve plant growth in the presence of heavy metals.
Afficher plus [+] Moins [-]Greywater in Egypt: the sustainable future of non-conventional water resources
2020
Batisha, Ayman F.
Egypt is a country with limited water resources. Egypt water needs are growing rapidly as a result of the population increase, climate change and development activities. The aim of the study is to analyse how Egypt can sustain its mega urban projects by utilizing greywater as a non-conventional water resource. A quantitative-based assessment has been conducted to investigate the overall evaluation of the greywater resources in Egypt. Greywater accounts for between 40 and 80% of the total water discharged from the house, and the total use of water for drinking and health use can be estimated at 10.4 billion cubic meters per year. The results show that the greywater resources may support a sustainable future of non-conventional water resources in a very positive way. Greywater can provide Egypt with about 4.15–8.30 billion cubic meters annually, which is a good support for water resources in Egypt. The paper concluded that greywater is an important resource to facilitate the success of the new mega urban projects. Egypt should maximize the share of greywater resources, especially in its new mega urban projects. Greywater resources can support Egypt and other arid and semiarid regions and countries in transition to a sustainable future.
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