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Identification of Lichen Plants and Butterflies Using Image Processing and Neural Networks in Cloud Computing
Published in P. Kaliraj, T. Devi, Artificial Intelligence Theory, Models, and Applications, 2021
P. Ponmurugan, K. Murugan, C. Panneerselvam
Bioactive compounds extracted from lichen thallus are being rendered several biological activities and promising anti-microbial agent alternatives to antibiotics. It is observed that lichen bioactive compounds have a large number of medicinal properties. More than 50% of the known lichen species exhibited medicinal values (Vartia, 1973). Most of the lichen compounds exert a broad spectrum of biological actions such as antifungal, antibacterial, antiviral, antimalarial antioxidant, anticancer, anti-inflammatory, anti-arthritis anti-analgesic, anti-pyretic, and antiproliferative activities (Tanas et al., 2010; Shrestha et al., 2015), including anti-snake venom properties (Kalidoss et al., 2020). The secondary metabolites are inevitable chemical substances, which assist lichen identification as well as using chemotaxonomy methods.
Activated Sludge Process for Refractory Pollutants Removal
Published in Maulin P. Shah, Removal of Refractory Pollutants from Wastewater Treatment Plants, 2021
Reyhan Ata, Gökçe Faika Merdan, Günay Yıldız Töre
Biosorption is the removal of metal ions from aqueous media by biomass. The biosorption (biological adsorption) of metals is generally based on adsorption, ion exchange, complexation, and micro-precipitation, and is a rapid and reversible event. It is known as a cost-effective biotechnological method for the treatment of low concentrations and high volumes of metals in wastewater using biomaterials such as bacteria, crab shells, fungus, and algae. In other words, the accumulation of biological materials in the cell surface or in the cell surface of waste materials in aqueous solutions is called biosorption. Uluözlü et al., in 2008, investigated the biosorption of Pb(II) and Cr(III) from aqueous solutions in their biosorption study with Parmelina tiliacea lichen species (Uluözlü et al. 2008). Ekmekyapar et al., in 2006, examined the biosorption of copper(II) from Cladonia rangiformis non-living dead biomass (Ekmekyapar et al. 2006). Yalçın et al, in 2010, studied the Cu+2 and Zn+2 biosorption of Roccella psychopsis species. With these features, lichens have been used as a biosorbent in metal removal in recent years (Yalçın et al. 2010).
Deterioration of materials
Published in A. M. Sowden, The Maintenance of Brick and Stone Masonry Structures, 2020
Lichens can be classified into three main types (foliose, fructicose and crustose) depending on the form of their thalli or surface growth. Foliose lichens have thalli in the form of leaves or scales which are attached to the surfaces by threads, whereas fructicose lichens have branching thalli which are attached to the surface at their base. The crustose type has a thallus that forms a crust in close contact with the stone surface; if the crust is removed by scrubbing or scraping, the thallus will regrow over a period of perhaps a year to its original dimensions. In many cases, the older or central part of the thallus becomes relatively inactive, perhaps as a result of accumulations of calcium oxalate, and will fall away to disclose a clean stone surface which will then be recolonized by the growth. In most cases crustose lichen activity is associated with densification of the immediate surface of the stone owing to deposition of calcium oxalate, but severe weakening of the surface may occur at a greater depth and, if crystallization also occurs through the presence of soluble salts or through freezing, the densified surface may spall away. In polluted atmospheres many species of lichen growth are suppressed or controlled, but some resistant species may be able to develop; pollution from, for example, fertilizer factories may result in accelerated lichen activity which may, in turn, lead to spalling or contour scaling at frequent intervals and so to progressive loss of the stone surface.
Lichen - air quality association rule mining for urban environments in the tropics
Published in International Journal of Environmental Health Research, 2023
Olanrewaju Lawal, Laud Charles Ochei
Air quality monitoring equipment and its maintenance are major challenges for monitoring in many low- and middle-income countries. The use of bioindicators provides a cost-effective option. However, this requires the collection of the initial dataset and the deployment of statistical or Machine Learning (ML) or Artificial Intelligence (AI) tools and techniques to identify the association between air quality parameters and Lichen Species. Forms, diversity, presence (or absence), and species of Lichens are the outcome of the integration of various pollutants over time (Conti and Cecchetti 2001). They are useful as bioindicators, early warning signals and in the diagnosis of causes of environmental problems (Dale and Beyeler 2001). Lichens are symbiotic organisms widely used as indicators of environmental changes and monitoring of air quality (Bako et al. 2008; Seed et al. 2013; Ite et al. 2014). There is only scanty literature about lichen communities and their application in air pollution studies in Nigeria. Extant literature covered only a very small region or single location, which is inadequate to create the required framework for using lichens as air quality indicators in the country. Numerous works exist across Europe and North America involving Lichen and air quality association, this is missing in Nigeria. A systematic review by Mallen-Cooper and Cornwell (2020) reported that 67% of the literature on lichens and bryophytes focussed on their utilisation indicators of air pollution and Africa and Australia have geographical knowledge gaps.
Bioaccumulation and sources identification of atmospheric metal trace elements using lichens along a rural–urban pollution gradient in the Safi-Essaouira coastal area
Published in Chemistry and Ecology, 2023
Essilmi Mohamed, Mohammed Loudiki, Abdelhay El Gharmali
Airborne metallic micropollutants occur in dissolved or particulate chemical forms that are highly bioassimilable by organisms [6]. The quantification of these toxic elements in atmospheric particles by chemical techniques is highly onerous, and therefore other bioassessment approaches have been used to indirectly assess the content of MTE in the air from urban and industrial areas [7–10]. Several organisms, such as lichens [11] and mosses [12], have been used as bioindicators in air pollution monitoring. Lichens are considered among the most efficient biological monitors of air pollution owing to their sensitivity to various metallic pollutants and their ability to accumulate and integrate high content of atmospheric MTE over time [13–15]. Several studies have widely used lichens as low-cost biomonitors of air pollution, since the pollutants concentrations accumulated in their thalli can be directly correlated with those present in the environment [14,16]. Furthermore, the determination of Pb isotopic composition of lichens has proven to be a valuable tool for tracking the air pollution sources and its circulation between different environmental matrices [17–19]. Different studies have used Pb isotopic ratios to identify and quantify Pb anthropogenic emissions sources [20–23]. Elemental ratios between two MTEs (e.g. Zn/Cu, Zn/Pb) are also used as indicators of anthropic and lithogenic sources contribution [23–25].
Techniques for harvesting, cell disruption and lipid extraction of microalgae for biofuel production
Published in Biofuels, 2021
Bioflocculation can take place as microalgal flocculation by secreted biopolymers such as extracellular polymeric substances (EPS). Bioflocculation eliminates the need for chemical flocculants; however, co-culturing microalgae with bacteria or fungi leads to contamination [35]. Microbial flocculants can act as the carbon source needed by flocculating microorganisms. A range of common soil bacteria secrete mucus with flocculating potential. Paenibacillus sp. [36] showed the highest flocculation efficiency for Chlorella vulgaris in combination with 6.8 mm CaCl2 as co-flocculant. A bioflocculant produced by Solibacilussilvestris was found to be effective in harvesting microalgae without any chemical coagulants. The bioflocculant did not affect the growth of the microalgae and can be conveniently reused [37]. Microalgal/fungal association occurs naturally in lichens. Symbiotically, microalgae fix CO2 and produce organic compounds, promoting the growth of fungus which in turn entraps the microalgae by hyphae production [38]. Also, the selected flocculant must be positively charged so as to attract to the negatively charged microalgal surface. One such bioflocculant is chitosan derived from chitin. Chitosan is considered an effective flocculant but performs only at low pH, which limits its use for microalgal harvesting, since microalgal cultures generally have a high pH [39]. A substitute for chitosan could be cationic starch, made from starch by adding quarternary ammonium groups. These ammonium groups are pH independent, making this a better option than chitosan. Among the other bioflocculants are poly γ glutamic acid extracted from Bacillus subtilis, and polymers present in flour from Moringa oleifera [33,40].