2,295 research outputs found

    Microbial characterization of a mine soil subjected to different remediation technologies combining organic and inorganic treatments and plant cultivation

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    RAMIRAN International ConferenceIn Portugal, additional research is needed if technologies based on the combined action of plants and the microbial communities they support within the rhizosphere are to be adopted in large-scale remediation actions (Nabais et al., 2008). Plants growing in abandoned mines are useful to indicate the mineral composition of the soil and they are able to accumulate or exclude toxic metals (Pratas et al., 2005). Taking into account that the mine degraded soils have low concentrations of plant nutrients, it is necessary to apply amendments to ensure plant cover when remediation technologies are present. But soil amendments and the development of a root system might induce shifts in the microbial community structure among the different treatments (Pérez-de-Mora et al., 2006). Moreover, data about the toxic effects of heavy metals on soil microorganisms indicated that heavy metal-sensitive bacteria are probably responsible for the decrease in bacterial activity and the competitive advantage of more tolerant ones resulted in a change in community composition (Díaz-Raviña and Bååth, 1996). Hence, relationships between the soil composition, plant species occurring above-ground and the soil microbial communities have been revealed in many research (Kourtev et al., 2003) providing an important link between above and below-ground processes in terrestrial ecosystems. Soil microbial community structure is increasingly being marketed as ecologically-relevant endpoint and it can realistically be incorporated for assessing the potential risks associated with soil amendment strategies on sustainability of soil ecosystems. Studies of different remediation technologies with mine soils in Portugal, including amendment materials from farming and industrial sources and the use of native plant species (Guiwei et al., 2008; de Varennes et al., 2009) revealed differential effects of treatments on soil enzymes and microbial respiration, suggesting a change in microbial communities. The information about this fact is scarce and had focused on soil biochemical properties, producing no clear results. Phospholipid fatty acid (PLFA) patterns are sensitive indicators of changes in microbial community structure. This technique has been used to elucidate different strategies employed by microorganism to adapt to changed environmental conditions under wide ranges of soil types, management practices, climatic origins and different perturbations (Zelles, 1999). The present study is the first attempt to characterize, by means of the analysis of PLFA patterns, soil microbial population from a Pb-contaminated mine soil subjected to different remediation technologies including revegetation with native herbaceous species

    Microbial community structure in a unlimed and limed mine contaminated soil (Pb, Cu, As) with different organic and inorganic treatments

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    RAMIRAN International ConferenceMine contaminated soils are very unfavourable environments with limiting factors, in particular residual high levels of heavy metals, soil acidity, lack of organic matter and poor substrate structure. Toxic effects of HM on soil microorganisms have been extensively studied (Frostegård et al., 1993; Bååth et al., 1998) and the measurements of community structure indicated that the HM had an effect resulting in a change in community composition (Ellis et al., 2003; Rajapaksha et al, 2004). Nowadays molecular biology techniques, such as the analysis of phospholipid fatty acid (PLFA) patterns, make it possible to study the microbial community structure of soil microorganisms. The PLFA technique has been used to elucidate different strategies employed by microorganism to adapt to changed environmental conditions under wide ranges of soil types, management practices, climatic origins and different perturbations (Zelles, 1999). By phospholipid fatty acid analysis it is possible to examine broad scale patterns in microbial community structure (Bååth et al. 2005) and generally, after the application of multivariate statistical analyses, whole community fatty acids profiles indicate which communities are similar or different. Determination both microbial community composition and biomass size by this direct method gives results that very closely represent the in situ soil conditions and is currently used for soil monitoring purposes (Nielsen and Winding, 2002). This study aimed to evaluate the effect of different remediation technologies in a mine contaminated soil including several organic and inorganic treatments combined with liming by the soil microbial community structure analysi

    Shifts in the structure of a mine contaminated soil (Pb, Cu, As) following different organic and inorganic treatments

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    RAMIRAN International ConferenceSoil microbial community structure is increasingly being marketed as ecologically-relevant endpoint and it can realistically be incorporated for assessing the potential risks associated with anthropogenic disturbances and soil amendment strategies on sustainability of soil ecosystems. In Portugal, additional research is needed if technologies based on the combined action of plants and the microbial communities they support within the rhizosphere are to be adopted in large-scale remediation actions (Nabais et al., 2008). The information about this fact in mine soils is scarce and had focused on soil biochemical properties, producing no clear results. Furthermore, the effects of phytoremediation as soil remediation technique and metal contamination on microbial community structural would be achieved by PLFA studies. By phospholipid fatty acid analysis it is possible to examine broad scale patterns in microbial community structure (Bååth et al. 2005) and generally, after the application of multivariate statistical analyses, whole community fatty acids profiles indicate which communities are similar or different. Determination both microbial community composition and biomass size by this direct method gives results that very closely represent the in situ soil conditions and is currently used for soil monitoring purposes (Nielsen and Winding, 2002). The present investigation studies the medium-term response in the soil microbial community structure after the application of different remediation technologies including several organic and inorganic treatments

    Sustainable energy management benchmark at wastewater treatment plant

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    Urban wastewater effluents bring large amounts of nutrients, organic matter, and organic microcontaminants into freshwater ecosystems. Ensuring the quality of wastewater treatment (WWT) is one of the main challenges facing the management of wastewater treatment plants (WWTPs). How-ever, achievement of high-quality standards leads towards significant energy consumption: usually the more intensive WWT process requires additional energies. Energy efficiency at WWTP is actual mainstream on the current sustainable development agenda. The WWTP processes and methods can be considered from the standpoint of material and energy flows according to circular economy paradigm, which offers great possibilities to reuse waste originating from WWT in order to receive renewable energy. The correlation between energy and quality issues to evaluate WWTP efficiency is of a great scientific and practical interest. The main goal of the paper is to check the dependency between these two main issues in WWTP management\u2014WWT quality and energy efficiency\u2014and to determine possible limits of such relation. The municipal sewerage system of Ekaterinburg, Russia was studied within this paper. The total length of centralized sewerage system in Ekaterinburg is over 1500 km of pipes within two main sewerage basins: northern and southern. The methodological framework for the current research consisted of three steps: (i) WWT quality evaluation, (ii) energy efficiency evaluation, and (iii) WWTP Quality/Energy (Q/E) efficiency dependency matrix. For the purpose of research, authors investigated the 2015\u20132018 period. The results showed that the outputs correlate with the technical conditions of WWTPs and the implementation of the best available techniques (BATs): most of the northern WWTP values are referred to the green zone (good rank), while the southern WWTP values are situated generally in the orange zone (unsatisfactory rank). The proposed methodological approach for Q/E dependency of WWT process creates a strong but simple tool for managers to evaluate the current success of the operation of WWTP and progress towards circular economy practices implementation

    PROTECTIVE EFFECT OF DIOSGENIN AGAINST CARBON TETRACHLORIDE AND CISPLATIN INDUCED HEPATOTOXICITY IN RATS

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    Background: Activation of hepatic stellate cells (HSC) plays central role in the development of liver fibrosis. In HSC activation, the transforming growth factor-1 (TGF-1) is considered to be the main stimuli factor. Diosgenin are the steroidal saponin and found in Trigonella foenum graecum Linn (Fenugreek) and some other species of Dioscorea. Diosgenin attenuates HSC activation by inhibiting transforming growth factor. Aim: In present study an attempt was made to explore the effect of diosgenin on liver fibrosis. Methods: Liver fibrosis was induced in rats by carbon tetrachloride (CCl4) 1 ml/kg intraperitoneally twice a week for 28 days and cisplatin 3mg/kg intraperitoneally at 0, 1, 3 week for 4 weeks. The extent of liver fibrosis was assessed by measuring the weight of liver and levels of total bilirubin (TBL), hydroxyproline (HP) and serum enzymes due to deposition of extracellular matrix (ECM). Results: The administration of diosgenin reduced the liver weight of CCl4 and cisplatin treated animals and reduced the TBL, HP level and serum enzymes significantly and inhibited liver fibrosis induced by CCl4 and cisplatin. Conclusion: The result obtained in the present investigation, Diosgenin treatment exerted significant hepatoprotective effect in animals by inhibiting ECM deposition and HSCs activation

    PROTECTIVE EFFECT OF DIOSGENIN AGAINST CARBON TETRACHLORIDE AND CISPLATIN INDUCED HEPATOTOXICITY IN RATS

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    Background: Activation of hepatic stellate cells (HSC) plays central role in the development of liver fibrosis. In HSC activation, the transforming growth factor-1 (TGF-1) is considered to be the main stimuli factor. Diosgenin are the steroidal saponin and found in Trigonella foenum graecum Linn (Fenugreek) and some other species of Dioscorea. Diosgenin attenuates HSC activation by inhibiting transforming growth factor. Aim: In present study an attempt was made to explore the effect of diosgenin on liver fibrosis. Methods: Liver fibrosis was induced in rats by carbon tetrachloride (CCl4) 1 ml/kg intraperitoneally twice a week for 28 days and cisplatin 3mg/kg intraperitoneally at 0, 1, 3 week for 4 weeks. The extent of liver fibrosis was assessed by measuring the weight of liver and levels of total bilirubin (TBL), hydroxyproline (HP) and serum enzymes due to deposition of extracellular matrix (ECM). Results: The administration of diosgenin reduced the liver weight of CCl4 and cisplatin treated animals and reduced the TBL, HP level and serum enzymes significantly and inhibited liver fibrosis induced by CCl4 and cisplatin. Conclusion: The result obtained in the present investigation, Diosgenin treatment exerted significant hepatoprotective effect in animals by inhibiting ECM deposition and HSCs activation

    Evaluation of Ca-Based Sorbents for Gaseous HCl Emissions Adsorption

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    The problem of acid gas exhaust emissions treatment has not been fully resolved at present. Dry adsorption of acid gases with alkaline sorbents is currently being investigated, to improve solid sorbents. In this study, 5 types of hydrated lime were characterised and tested. The sorption capacities were measured by means of a system consisting of a feed line (HCl/N2), a thermostatic reactor and a water absorber. The physical characteristics of sorbent samples were also compared. Analyses conducted with scanning electronic microscopy revealed that sample C1 showed uniform particle distribution. Samples C2 and C3 showed the co-presence of fine and coarse particles. Sample C4 showed very fine particles with agglomeration phenomena. In sample C5, fibrous elements were found. Energy dispersive spectrometry (EDS) analyses showed a similar composition of the samples, with the exception of the presence of Mg in some of them. After 30 min of testing, the following differences in sorption capacities with respect to C1 (3.59 mg g−1) were found: C2, −20%; C3, −13%; C4, −17%; C5, −3%. Higher sorption capacities were associated with more uniform particle size distributions. Conversely, agglomeration of fine particles may have adversely affected the performance of sorbents

    Evaluation of Immunomodulatory activity of Diosgenin in rats

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    Background: The immune system is intrinsic to health. Modulation of the immune responses to alleviate the diseases by using herbal plants has been of interest for many years. Diosgenin, a naturally occurring steroid saponin mainly present in the seeds of fenugreek (Trigonella foenum graecum) and in the root tubers of wild yams (Dioscorea villosa). Activation of specific and nonspecific immunity results in stimulation of immune response. Diosgenin has the positive effects on both specific and nonspecific immunity. Aim: To study the immunomodulatory activity of Diosgenin in albino wistar rats. Method: The suspension of Diosgenin was given orally at the dosage level of 50, 100 and 150 mg/kg for 21 days in a rat. The immunomodulatory activity on specific and non-specific immunity was studied by heamagglutination antibody (HA) titer, delayed type hypersensitivity (DTH) response and carbon clearance test. Immunosuppression in a rat was induced by using Cyclophosphamide (100 mg/kg, p.o.). Sheep red blood cells (SRBCs) were used as antigen (0.1ml 20% SRBCs). Result: Diosgenin exhibited significant increase in the production of antibody titer in response to SRBC antigen. A significant increase in both primary and secondary HA titer was observed in immunosuppressed group treated with Diosgenin when compared with negative control. A significant increase in the DTH response was observed in immunosuppressed animals treated with Diosgenin, pre-sensitized with SRBCs antigen. Diosgenin exhibited significant increase in phagocytic index against control group, indicating the stimulation of the reticuloendothelial system. Conclusion: The study indicates that Diosgenin triggers stimulatory effect on specific and nonspecific immune response. The immunostimulant effect of Diosgenin could be attributed due to its saponin glycoside

    Factors Affecting Corporate Happiness within Technology-Based Firms in Andalucia

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    Studies on corporate happiness have emerged as a new approach to management and productivity. The theory around this leadership focus could change the way firms arrange their own business objectives and goals. In this paper, happiness, as a construct, is analyzed from an economical and entrepreneurial perspective. The goal is to determine if happiness influences productivity and work environments in technology-based firms (TBF) in Andalucia, Spain. A survey, completed by 41 employees, was elaborated on and applied to a group of employees in TBF, based in Sevilla. The results confirm that a happier environment is present in TBF than in non-technological firms. This is due to the strategies applied in TBF to improve happiness and wellness perception in their employees and the influence in productivity and, therefore, in organizational competitiveness
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