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Background: Water filtration units have been faced problems in water turbidity removal related to their media, which is determined by qualitative indices. Moreover, Current qualitative indices such as turbidity and escaping particle number could not precisely determine the efficiency of the media in water filtration, so defining new indices is essential. In this study, the efficiency of Anthracite-Silica and LECA-Silica media in turbidity removal were compared in different operating condition by using modified qualitative indices. Methods: The pilot consisted of a filter column (one meter depth) which consisted of a layer of LECA (450 mm depth) and a layer of Silica sand (350 mm depth. Turbidities of 10, 20, and 30 NTU, coagulant concentrations of 4, 8, and 12 ppm and filtration rates of 10, 15, and 20 m/h were considered as variables. Results: The LECA-Silica media is suitable media for water filtration. Averages of turbidity removal efficiencies in different condition for the LECA-Silica media were 85.8±5.37 percent in stable phase and 69.75±3.37 percent in whole operation phase, while the efficiency of total system were 98.31±0.63 and 94.49±2.97 percent, respectively. Conclusion: The LECA layer efficiency in turbidity removal was independent from filtration rates and due to its low head loss; LECA can be used as a proper medium for treatment plants. Results also showed that the particle index (PI) was a suitable index as a substitute for turbidity and EPN indices.

Myosins are key components of the eukaryotic cytoskeleton, providing motility for a broad diversity of cargoes. Therefore, understanding the origin and evolutionary history of myosin classes is crucial to address the evolution of eukaryote cell biology. Here, we revise the classification of myosins using an updated taxon sampling that includes newly or recently sequenced genomes and transcriptomes from key taxa. We performed a survey of eukaryotic genomes and phylogenetic analyses of the myosin gene family, reconstructing the myosin toolkit at different key nodes in the eukaryotic tree of life. We also identified the phylogenetic distribution of myosin diversity in terms of number of genes, associated protein domains and number of classes in each taxa. Our analyses show that new classes (i.e., paralogs) and domain architectures were continuously generated throughout eukaryote evolution, with a significant expansion of myosin abundance and domain architectural diversity at the stem of Holozoa, predating the origin of animal multicellularity. Indeed, single-celled holozoans have the most complex myosin complement among eukaryotes, with paralogs of most myosins previously considered animal specific. We recover a dynamic evolutionary history, with several lineage specific expansions (e.g., the myosin III-like gene family diversification in choanoflagellates), convergence in protein domain architectures (e.g., fungal and animal chitin synthase myosins), and important secondary losses. Overall, our evolutionary scheme demonstrates that the ancestral eukaryote likely had a complex myosin repertoire that included six genes with different protein domain architectures. Finally, we provide an integrative and robust classification, useful for future genomic and functional studies on this crucial eukaryotic gene family. [ABSTRACT FROM AUTHOR]

As a nucleolar complex for small-subunit (SSU) ribosomal RNA processing, SSU processome has been extensively studied mainly in Saccharomyces cerevisiae but not in diverse organisms, leaving open the question of whether it is a ubiquitous mechanism across eukaryotes and how it evolved in the course of the evolution of eukaryotes. Genome-wide survey and identification of SSU processome components showed that the majority of all 77 yeast SSU processome proteins possess homologs in almost all of the main eukaryotic lineages, and 14 of them have homologs in archaea but few in bacteria, suggesting that the complex is ubiquitous in eukaryotes, and its evolutionary history began with abundant protein homologs being present in archaea and then a fairly complete form of the complex emerged in the last eukaryotic common ancestor (LECA). Phylogenetic analysis indicated that ancient gene duplication and functional divergence of the protein components of the complex occurred frequently during the evolutionary origin of the LECA from prokaryotes. We found that such duplications not only increased the complex’s components but also produced some new functional proteins involved in other nucleolar functions, such as ribosome biogenesis and even some nonnucleolar (but nuclear) proteins participating in pre-mRNA splicing, implying the evolutionary emergence of the subnuclear compartment—the nucleolus—has occurred in the LECA. Therefore, the LECA harbored not only complicated SSU processomes but also a nucleolus. Our analysis also revealed that gene duplication, innovation, and loss, caused further divergence of the complex during the divergence of eukaryotes. [ABSTRACT FROM AUTHOR]

Highlights: [•] Leca was studied with respect to sorption and chemisorption of H2S, MT and DMS. [•] DMS is not degraded but H2S and MT are removed with variable efficiency. [•] O2 is not necessary for chemisorption of H2S and MT. [•] Moisture content has an influence on removal of H2S and MT. [•] Dimethyl disulphide and dimethyl trisulphide are observed as gaseous by-products. [Copyright &y& Elsevier]

Abstract: Constructed wetlands (CWs) are receiving a renewed attention as a viable phytotechnology for treating agricultural wastewaters and for the removal of more specific pollutants, in particular recalcitrant ones. In this work, the performance of CW mesocosms using light expanded clay aggregates (LECA) as the bed's substrate and planted with Phragmites australis was investigated for treatment of olive mill wastewater (OMW), swine wastewater (SW) contaminated with oxytetracycline and water contaminated with herbicide MCPA (2-methyl-4-chlorophenoxyacetic acid). Both wastewaters (OMW and SW) initially presented high organic matter content and total suspended solids which were removed by the system with efficiencies higher than 80%. Removal of polyphenols in OMW and nitrogen compounds in SW also showed similar or higher efficiencies in comparison with other treatment systems reported in the literature. The antibiotic oxytetracycline was completely removed from SW within the assay period in unplanted LECA beds, but planted beds allowed a significantly faster removal. In regard to water contaminated with MCPA, the results showed that LECA has a large sorption capacity for this herbicide (removal efficiencies of 56–97%). In general, considerably higher pollutant removal efficiencies were obtained when plants were used (up to 28% higher). The results obtained are indicative that CWs with LECA as substrate may be an adequate option for agricultural wastewater treatment. [Copyright &y& Elsevier]

Prediction of concrete properties is an important issue for structural engineers and different methods are developed for this purpose. Most of these methods are based on experimental data and use measured data for parameter estimation. Three typical methods of output estimation are Categorized Linear Regression (CLR), Multiple Linear Regression (MLR) and Artificial Neural Networks (ANN). In this paper a statistical cleansing method based on CLR is introduced. Afterwards, MLR and ANN approaches are also employed to predict the compressive strength of structural lightweight aggregate concrete. The valid input domain is briefly discussed. Finally the results of three prediction methods are compared to determine the most efficient method. The results indicate that despite higher accuracy of ANN, there are some limitations for the method. These limitations include high sensitivity of method to its valid input domain and selection criteria for determining the most efficient network. [ABSTRACT FROM AUTHOR]

Eukaryogenesis, the origin of the eukaryotic cell, represents one of the fundamental evolutionary transitions in the history of life on earth. This event, which is estimated to have occurred over one billion years ago, remains rather poorly understood. While some well-validated examples of fossil microbial eukaryotes for this time frame have been described, these can provide only basic morphology and the molecular machinery present in these organisms has remained unknown. Complete and partial genomic information has begun to fill this gap, and is being used to trace proteins and cellular traits to their roots and to provide unprecedented levels of resolution of structures, metabolic pathways and capabilities of organisms at these earliest points within the eukaryotic lineage. This is essentially allowing a molecular paleontology. What has emerged from these studies is spectacular cellular complexity prior to expansion of the eukaryotic lineages. Multiple reconstructed cellular systems indicate a very sophisticated biology, which by implication arose following the initial eukaryogenesis event but prior to eukaryotic radiation and provides a challenge in terms of explaining how these early eukaryotes arose and in understanding how they lived. Here, we provide brief overviews of several cellular systems and the major emerging conclusions, together with predictions for subsequent directions in evolution leading to extant taxa. We also consider what these reconstructions suggest about the life styles and capabilities of these earliest eukaryotes and the period of evolution between the radiation of eukaryotes and the eukaryogenesis event itself. [ABSTRACT FROM AUTHOR]

Endocytosis is a vital cellular process maintaining the cell surface, modulating signal transduction and facilitating nutrient acquisition. In metazoa, multiple endocytic modes are recognized, but for many unicellular organisms the process is likely dominated by the ancient clathrin-mediated pathway. The endocytic system of the highly divergent trypanosomatid Trypanosoma brucei exhibits many unusual features, including a restricted site of internalization, dominance of the plasma membrane by GPI-anchored proteins, absence of the AP2 complex and an exceptionally high rate. Here we asked if the proteins subtending clathrin trafficking in trypanosomes are exclusively related to those of higher eukaryotes or if novel, potentially taxon-specific proteins operate. Co-immunoprecipitation identified twelve T. brucei clathrin-associating proteins ( TbCAPs), which partially colocalized with clathrin. Critically, eight TbCAPs are restricted to trypanosomatid genomes and all of these are required for robust cell proliferation. A subset, TbCAP100, TbCAP116, TbCAP161 and TbCAP334, were implicated in distinct endocytic steps by detailed analysis of knockdown cells. Coupled with the absence of orthologs for many metazoan and fungal endocytic factors, these data suggest that clathrin interactions in trypanosomes are highly lineage-specific, and indicate substantial evolutionary diversity within clathrin-mediated endocytosis mechanisms across the eukaryotes. [ABSTRACT FROM AUTHOR]

Photocatalytic degradation of ammonia on supported TiO nanoparticles was investigated. The TiO nanoparticles used as photocatalyst were coated on light expanded clay aggregate granules (LECA), which is a porous and light weight support. Photocatalytic reaction activity of prepared catalyst was determined by ammonia degradation from water synthetically polluted with ammonia. Experiment results showed significantly high photocatalytic activity for the immobilized catalysts. The ammonia was removed more than 85% within 300 min of the process with optimum calcinations temperature 550 °C and pH 11. Kinetics of the photocatalytic reaction followed a pseudo-first order model. XRF, XRD and SEM analyses revealed a rather uniform coating of TiO on the support. By using floated TiO/LECA as a photocatalyst in aqueous solution of NH, the ammonia was photodegraded into N and H gases, while NO and NO were formed at very low concentrations. [ABSTRACT FROM AUTHOR]

Inadequate moisture supply is one of the important factors limiting crop yields in the world. Increasing the efficiency of moisture available has an important role on the crop-producing capacity of the soil. This paper presents the results of the laboratory experiments conducted to assess the influence of two mulches of windy sand and light expanded clay aggregate (LECA) with three thicknesses (1, 3, and 4 cm) on soil surface in soil columns. Loamy soil was taken from the experimental site in Bayaz of Rafsanjan (a city in Kerman province in Iran). These experiments were done as completely randomized design with two treatments of mulches (windy sand and LECA) and tree replicates. The results show that the columns of treated soil with mulches had lower evaporation as compared to the control. The rate of evaporation from the soil surface of columns was decreased with increasing the thickness from 1 to 4 cm of each of the two mulches. The LECA mulch was more effective in reducing evaporation from the soil surface than the windy sand mulch with the same thicknesses. The most effective among the thicknesses for mulches was 3 cm. [ABSTRACT FROM AUTHOR]

This paper determines mix proportions of high-strength structural lightweight concrete (HSSLWC), which reduces the weight of concrete by using expanded aggregate clay (Leca). In order to produce HSSLWC, mineral and chemical admixtures have been used along with limestone that reduces porosity and increases strength. Tests for specific gravity, and compressive, indirect tensile and flexural strengths were carried out on the specimens. The effect of curing on the compressive strength was investigated by keeping some specimens in open air. The results obtained showed that by using Leca, a lightweight structural concrete (LWSC) can be achieved, with dry density in the range of 1,610-1,965 kg/m and compressive strength in the range of 34-67 MPa, based on cube specimens with 100 mm side length. Limestone significantly improved the mechanical properties of concrete whenever mixed with lightweight aggregates. [ABSTRACT FROM AUTHOR]

Abstract: Lightweight expanded clay aggregate (LECA) has been explored as a sorbent for the removal of PAHs (phenanthrene, fluoranthene and pyrene) from water. The efficacy of LECA as a sorbent for PAHs was assessed using contact time, mass of sorbent and sorption isotherms in a series of batch experiments. Maximum (optimum) sorption was reached at 21h after which the amount of PAHs sorbed remained almost constant. Batch experiments were conducted by shaking a 100ml solution mixture of individual PAHs (containing 0.02mg/L) with LECA. The maximum sorption was 70.70, 70.82 and 72.12%, respectively for phenanthrene, fluoranthene and pyrene when a mass of 0.2g of sorbent was used. There was an increase in sorption as a result of an increase in mass of sorbent until a maximum was reached at a mass of 4.0g LECA with 92.61, 93.91 and 94.15% sorption of phenanthrene, fluoranthene and pyrene respectively. Sorption data were fitted to the linearised forms of the Freundlich and Langmuir isotherm models to determine the water-LECA partitioning coefficient. Physical sorption caused by the aromatic nature of the compounds was the main mechanism that governed the removal process while the hydrophobicity of the PAHs also influenced the sorption capacity. LECA can be used as an alternative method for aqueous PAHs removal. [Copyright &y& Elsevier]

This study examined the structural behaviour of lightweight concrete (LWAC) made with different gradings of lightweight aggregates (expanded clay aggregates LECA) and normal weight aggregates with the aim to investigate the effect of partial replacement of the normal weight aggregates with different gradings of the LECA. The paper focused on performance parameters such as compressive strength (f'c), splitting tensile strength, unit weight and workability of concrete. The LWAC was compared to normal aggregate concrete with different cement contents. The results indicate that both LECA aggregate size and its percentage and the cement content have significant effects on the properties of lightweight concrete. A critical finding of the study is related to the tensile strength (ft) of LWAC, which was shown to be overestimated if determined using the recommendations made by the Dutch code VBC 1990; a new correlation between ft and f'c is presented in this paper. In spite of the good results obtained for this type of LWAC relative to normal weight concrete, there is no certain mix proportion that can be generally used, as is the case for normal weight concrete, and more studies are still needed to ensure its optimal proportions. [ABSTRACT FROM AUTHOR]

The article discusses a study which compared the performance of extended aeration activated sludge (EAAS) with submerged membrane bioreactors (SMBR) systems in wastewater treatment. The study established the chemical oxygen demand (COD) concentration of the wastewater. It showed that the SMBR system produced a better quality effluent than the other system.

Backgrounds and Objectives: Improvement of water quality standards and inability of mono layer filters in producing such quality caused researchers attended to multi layer filters. Due to specific characteristics of anthracite and leca can improve removal of organic materials and Surface over flow rate. The aim of this research was evaluation performance of dual media filters (anthracite/leca) in removing of organic materials and turbidity from Ahvaz Water treatment plant Materials and Methods: In this study two pilots built for investigation of mono layer filter and dual media filter performance. The researcher used sand in structure's media of mono layer filter and composition of anthracite, sand and leca in structure's media of dual media filter, respectively. In this study single and dual layer filter pilot examined in term of organic matter and turbidity removal efficiency. Results: Results indicated that removal of organic matter by single layer filter (sand), dual media filter (anthracite, and sand), dual media filter (leca and sand) was 7%,12%,4/2% respectively. And also Turbidity removal by single layer filter(sand), dual media filter (anthracite and sand), dual media filter (leca and sand) was also 69%, 80%, 74% respectively. Conclusion: Results of this study showed that upgrading of Single layer to dual layer with anthracite and leca media can't show a significant affect in TOC removal. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes modification of LECA (light expanded clay aggregate) with Fenton reagent and determines removal of arsenite and arsenate ions from an aqueous solution. The influence of pH, contact time and Fe2+/H2O2 on modification were investigated and adsorption characteristics were examined before and after modification. Isotherm studies were carried out by studying the effects of various parameters such as pH, contact time, adsorbent concentration and initial concentration of arsenite and arsenate. The equilibrium adsorption data were fitted to Langmuir and Freundlich adsorption models, and the model parameters were evaluated. One gram of LECA is found enough to remove 96% and 99% of the As (III) and As (V) from an aqueous solution of 150μgL−1 at pH 2 and 4 respectively with a shaking time of 60min. Column adsorption results indicated that no arsenic was found in the effluent solution up to about 10 and 18 bed volumes of As (III) and As (V), respectively. [Copyright &y& Elsevier]

In this article, the author discusses the kinetic model which he proposed in order to have better understanding of the oxygen radical formation in mitochondria. In this model, the major determinant in radical formation is the ratio between electrons that enter the respiratory chain through flavin adenine dinucleotide plus hydrogen2 (FADH2) or nicotinamide adenine dinucleotide plus hydrogen (NADH). This study found that longer fatty acid shows higher ratio and higher ratio means higher level of radical formation.

Abstract: This paper aims to collect and analyse existing information on different filter media used for phosphorus (P) removal from wastewater in constructed wetlands. The most commonly used materials are categorized as natural materials (considered in 39 papers), industrial byproducts (25 papers) and man-made products (10 papers). A majority of studies on sorbents have been carried out in lab-scale systems as batch experiments, and only very few studies have highlighted results on full-scale systems. Among the great variety of filter media studied, most of materials had a pH level >7 and high Ca (CaO) content. The highest P-removal capacities were reported for various industrial byproducts (up to 420g P kg−1 for some furnace slags), followed by natural materials (maximum 40g P kg−1 for heated opoka) and man-made filter media (maximum 12g P kg−1 for Filtralite). We found a significant positive Spearman Rank Order Correlation between the P retention and CaO and Ca content of filter materials (R 2 =0.51 and 0.43, respectively), whereas the relation of P retention to pH level was weak (R 2 =0.22) but significant. There is probably an optimal level of hydraulic loading rate at which the P removal is the highest. Additional important factors determining the applicability of filter materials in treatment wetlands such as saturation time, availability at a local level, content of heavy metals, and the recyclability of saturated filter media as fertilizer should be taken into consideration. [Copyright &y& Elsevier]

Abstract: Understanding early evolution is a major challenge for the post-genomic era. A promising way to tackle this issue is to analyze the evolutionary history of key cellular systems through phylogenomic approaches. The current availability of genomic data from representatives of diverse lineages (especially eukaryotes), together with the ever growing number of proteomic characterizations now provides ample material to apply this type of analyses to trace back the origin and evolution of the three domains of life. Here, we have reconstructed the composition of the ancestral mitochondrial ribosome in the Last Eukaryotic Common Ancestor (LECA) and investigated its subsequent evolution in six major eukaryotic supergroups. We infer that LECA possessed a mitochondrial ribosome that was already much larger than its bacterial ancestor, with 19 additional specific proteins, indicating that a certain amount of time occurred between initial endosymbiosis at the origin of the mitochondrion and the diversification of present-day eukaryotic supergroups. Subsequently, mitochondrial ribosomes appear to have undergone a very dynamic evolutionary history in the different eukaryotic lineages, involving the loss of different sets of ribosomal protein-coding genes, their transfer to the host genome, as well as the acquisition of many novel components. This chaotic history for a such fundamental cellular machinery is puzzling, especially when compared to cytosolic, bacterial or chloroplastic ribosomes, which are much more stable. Intriguingly, archaeal ribosomes also show a very dynamic nature, with multiple independent losses among lineages. [ABSTRACT FROM AUTHOR]

Abstract: Microcosm constructed wetlands systems established with a matrix of light expanded clay aggregates (LECA) and planted with Typha spp. were used to evaluate their ability to remove pharmaceuticals ibuprofen, carbamazepine and clofibric acid from wastewaters. Seasonal variability of these systems’ performances was also evaluated. Overall, removal efficiencies of 96%, 97% and 75% for ibuprofen, carbamazepine and clofibric acid, respectively, were achieved under summer conditions after a retention time of 7days. In winter, a maximum loss of 26% in removal efficiency was observed for clofibric acid. Removal kinetics was characterized by a fast initial step (>50% removal within 6h) mainly due to adsorption on LECA but, on a larger timescale, plants also contributed significantly to the system’s performance. Despite the fact that further tests using larger-scale systems are required, this study points to the possible application of these low-cost wastewater treatment systems for dealing with pharmaceuticals contaminated wastewater. [Copyright &y& Elsevier]

Microcosm constructed wetland systems established with a matrix of light expanded clay aggregates (LECA) and Typha spp. or Phragmites australis were used to evaluate their ability to remove atenolol from wastewater. Combined with an efficient SPE concentration step, the use of HPLC-DAD yielded an analytical method for atenolol quantification with very low LOQ (9 ng mL-1) and high reproducibility (RSD < 4%). Overall removal efficiencies of 92.5% and 94.5% were achieved after a retention time of only 4 days with the microcosm systems planted with Phragmites australis and Typha spp., respectively. The removal kinetics was characterised by an initial fast step (removal of about 75% after just 24 h) which is mainly attributable to adsorption on the LECA matrix. Atenolol removal in LECA beds continues to increase in a steady pace up to the end of the assay (8 days) being nevertheless about 5-10% lower than those observed in the planted beds after the first 4 days. For the retention time of 4 days most of the atenolol is removed by the LECA matrix but an additional 12-14% of the overall removal efficiency can be attributed to the Typha and Phragmites plants, which is in agreement with other published reports. Despite the fact that further tests using larger-scale flowing systems are required to evaluate fully the atenolol behaviour in constructed wetlands, this study points to the possible application of these low-cost wastewater treatment systems to treat atenolol contaminated wastewater. [ABSTRACT FROM AUTHOR]

• Efficiency of bacteria and fiber to improve properties of LWFC is presented. • CaCO 3 crystals precipitated by bacterial strains have different effects on balling phenomenon. • Bacillus licheniformis has higher efficiency on the balling reduction. • Forming calcite on LWFC is proven through SEM, EDX, and XRD analysis. This research investigated the impact of calcium carbonate precipitation induced by the activity of four microbial strains known as Sporosarcina pasteurii , Bacillus megaterium , Sporosarcina ureae , and Bacillus licheniformis at cell concentrations of 107 cells/ml on lightweight fiber concrete (LWFC). Three mixed designs with different fiber percentages (0%, 0.5%, and 1%) were considered for evaluation of the effects of these bacteria and polypropylene fiber on the mechanical properties and durability of LWC, which contained Leca aggregate. The experimental results indicated that the simultaneous addition of bacteria and fiber was effective and improved compressive, tensile, and flexural strength. It also reduced concrete water absorption and permeability in the specimens. In specimens with B. licheniformis and 1% fiber, a maximum increase of approximately 32.65% was observed in tensile strength and a 28.39% decrease was observed in water absorption with respect to the control specimens. A comparison of the bacterial specimens revealed that B. licheniformis and B. megateterium performed better in the induction of calcium carbonate precipitation and distribution of fiber in the concrete matrix than S. pasteurii and S. ureae to reduce the balling phenomenon. In addition, SEM-EDX and XRD analyses were conducted to verify the formation of calcium carbonate in the concrete matrix and characterize the crystalline phases of the calcite. [ABSTRACT FROM AUTHOR]

The efficiency of constructed wetlands systems in the removal of pollutants can be significantly enhanced by using a support matrix with a greater capacity to retain contaminants by sorption phenomena, ionic exchange or other physico-chemical processes. The aim of this work was to evaluate the efficiencies of 3 different materials, Light Expanded Clay Aggregates [LECA] (in two different particle sizes), Expanded Perlite and Sand, for the removal from water of one pharmaceutical compound (clofibric acid) and one pesticide (MCPA). Both belong to the class of phenoxyacetic compounds. In addition, relationships were established between the compounds'' removal efficiencies and the physico-chemical properties of each material. LECA exhibited a high sorption capacity for MCPA, while the capacity for clofibric acid was more modest, but still significant. In contrast, perlite had a very limited sorption capacity while sand did not exhibit any sorption capacity for any of the compounds. LECA with smaller particle sizes showed higher efficiencies than larger grade LECA and can achieve efficiencies near 100% for the lower concentrations in the order of 1 mg l−1. However, the use of these smaller particle media at larger scales may present problems with hydraulic conductivities. The results show that expanded clay presents important advantages in laboratory studies and could be used as a filter medium or a support matrix in constructed wetlands systems. [Copyright &y& Elsevier]

Analytical standardised reversed phase liquid chromatography (RPLC) data can be helpful in finding a suitable solvent combination for isolation of fungal metabolites by high‐speed counter current chromatography. Analysis of the distribution coefficient ( K D ) of fungal metabolites in a series of biphasic systems consisting of n ‐heptane–ethyl acetate (EtOAc)–methanol (MeOH)–water has been used to illustrate the relationship between the RPLC retention indexes and K D 's. The relationship can be used to select a suitable solvent combination for HSCCC, as demonstrated by the isolation of two new cyclic peptides from a crude fungal extract. [ABSTRACT FROM AUTHOR]

The present study examined the potential of some roughing filter media, prepared from locally available materials in removing organic matter and turbidity from surface water. Also, the study included testing the efficiency of roughing filter followed by slow sand filter in minimizing the suspended load on the subsequent water treatment steps. Based on microorganisms removal and turbidity data, filter media consisted of three layers of gravel ranked top among six of the media tested, showing 84–100% removal for chlorophyll `a', green algae, blue-green algae, diatoms, total algal count, bacterial count (at 22 and 37 °C), total coliforms, faecal coliform, faecal streptococci, yeast and Candida albicans. Using slow sand filter after roughing filter improved the percentage removal of turbidity, where it reached up to 83% after roughing filter while it reached 92% after slow sand filter. From the view point of aesthetic quality of the filtered water, the results of the analyzed physico-chemical parameters showed no change before and after the use of the roughing and slow sand filters. [ABSTRACT FROM AUTHOR]

Bacteria readily form resilient phenotypes to counter environmental and antibiotic stresses. Here, we demonstrate a class of small molecules that inhibit a wide range of Pseudomonas aeruginosa phenotypes and enable antibiotics to kill previously tolerant bacteria, preventing the transition of tolerant bacteria into a persistent population. We identified two proteins, type IV pili and lectin LecA, as receptors for our molecules by methods including a new label-free assay based on bacterial motility sensing the chemicals in the environment, the chemical inhibition of bacteriophage adsorption on pili appendages of bacteria, and fluorescence polarization. Structure-activity relationship studies reveal a molecule that inhibits only pili appendage and a class of chimeric ligands that inhibit both LecA and pili. Important structural elements of the ligand are identified for each protein. This selective ligand binding identifies the phenotypes each protein receptor controls. Inhibiting LecA results in reducing biofilm formation, eliminating small colony variants, and is correlated with killing previously tolerant bacteria. Inhibiting pili appendages impedes swarming and twitching motilities and pyocyanin and elastase production. Because these phenotypes are controlled by a broad range of signaling pathways, this approach simultaneously controls the multiple signaling mechanisms preventing bacteria to elude antibiotic treatments.

• Improved performance of expanded clay (EC) aggregates by coating with cementitious composites. • Two coating mixes used: Cement with silica fume and cement with fly-ash. • Coated aggregates (CEC) show 60% lower water absorption and up to 200% increase in strength. • Concrete made with CEC show up to 150% increase in the specific strength and 50% drop in the RCPT charge. • Costing index justifies additional cost of coating with the improvements in concrete properties. Lightweight expanded clay (EC) aggregates help in decreasing the dead load of the structure and reduce the concrete demand in foundations and other major structural members. However, a major drawback is their high water-absorption and permeability which degrades the transport properties of the concrete, and low strength which results in a concrete too weak to actively participate in load bearing. The present study demonstrates a solution to improve the performance of EC aggregates by coating with different cementitious composites before adding in the lightweight concrete (LWC). Two coating mixes, cement with silica fume and cement with fly-ash, were used to coat EC aggregates with multiple layers. The effect of coat thickness on the density, strength, and cost of EC was examined. The coated EC (CEC) aggregates showed a 60% decrease in the water absorption test, and a 200% increase in the aggregate strength. The concrete made using CEC showed up to 150% increase in the specific compressive strength, and up to 50% drop in the charge passed during rapid chloride permeability tests. Among the coats, the fly-ash (FA) mixes performed at par with the silica fume (SF) mixes in all the tests. Costing index calculated using the cost and specific strength of the LWCs showed a reduction with increasing no. of coats. Considering the high cost of SF, the use of FA coated EC aggregates is recommended to improve the concrete performance and justify the cost involved in their production. [ABSTRACT FROM AUTHOR]

• Lightweight expanded clay aggregate (LECA) characterization. • LECA friction angle. • LECA water absorption. • Lightweight geotechnical fills. Lightweight expanded clay aggregate (LECA) is a manufactured aggregate with many uses in construction, such as aggregate for the lightweight concrete or like geotechnical fill. The properties of the material may vary depending on the manufacturer or the applications envisaged for the aggregate. This paper makes an analysis of some properties of the LECA 10/20 (grain size between 10 and 20 mm) manufactured in Portugal by Arlita. The weight density of the grain and the aggregate, water absorption, deformability or resistance to shear are studied based on an extensive set of tests carried out in the Laboratorio de Geotecnia of CEDEX in Madrid (Spain). Among other tests, the dimension and dry weight density of more than 1500 grains has been determined. Direct shear tests of 300 mm were made, 6″ triaxial tests, confined compression tests or water absorption tests over time (keeping samples submerged for more than 18 months) were carried out. Throughout the article, a comparison is made between the results obtained and other results available in the scientific literature. The results obtained from this set of tests are directly applicable to the design of LECA fillings. And a novel model is presented that allows estimating the water absorption of LECA grains over time. [ABSTRACT FROM AUTHOR]

Abstract Background The Anaphase Promoting Complex or Cyclosome (APC/C) is the largest member of the ubiquitin ligase [E3] family. It plays a crucial role in the control of the cell cycle and cell proliferation by mediating the proteolysis of key components by the proteasome. APC/C is made of a dozen subunits that assemble into a large complex of ~1.5 MDa, which interacts with various cofactors and targets. Results Using comparative genomic and phylogenetic approaches, we showed that 24 out of 37 known APC/C subunits, adaptors/co-activators and main targets, were already present in the Last Eukaryotic Common Ancestor (LECA) and were well conserved to a few exceptions in all present-day eukaryotic lineages. The phylogenetic analysis of the 24 components inferred to be present in LECA showed that they contain a reliable phylogenetic signal to reconstruct the phylogeny of the domain Eucarya. Conclusions Taken together our analyses indicated that LECA had a complex and highly controlled modern-like cell cycle. Moreover, we showed that, despite what is generally assumed, proteins involved in housekeeping cellular functions may be a good complement to informational genes to study the phylogeny of eukaryotes.

Pseudomonas aeruginosa is an opportunistic ESKAPE pathogen that produces two lectins, LecA and LecB, as part of its large arsenal of virulence factors. Both carbohydrate-binding proteins are central to the initial and later persistent infection processes, i. e. bacterial adhesion and biofilm formation. The biofilm matrix is a major resistance determinant and protects the bacteria against external threats such as the host immune system or antibiotic treatment. Therefore, the development of drugs against the P. aeruginosa biofilm is of particular interest to restore efficacy of antimicrobials. Carbohydrate-based inhibitors for LecA and LecB were previously shown to efficiently reduce biofilm formations. Here, we report a new approach for inhibiting LecA with synthetic molecules bridging the established carbohydrate-binding site and a central cavity located between two LecA protomers of the lectin tetramer. Inspired by in silico design, we synthesized various galactosidic LecA inhibitors with aromatic moieties targeting this central pocket. These compounds reached low micromolar affinities, validated in different biophysical assays. Finally, X-ray diffraction analysis revealed the interactions of this compound class with LecA. This new mode of action paves the way to a novel route towards inhibition of P. aeruginosa biofilms., (© 2021 The Authors. ChemBioChem published by Wiley-VCH GmbH.)

It is puzzling why life on Earth consisted of prokaryotes for up to 2.5 ± 0.5 billion years (Gy) before the appearance of the first eukaryotes. This period, from LUCA (Last Universal Common Ancestor) to LECA (Last Eucaryotic Common Ancestor), we have named the Lucacene, to suggest all prokaryotic descendants of LUCA before the appearance of LECA. Here we present a simple model based on horizontal gene transfer (HGT). It is the process of HGT from Bacteria to Archaea and its reverse that we wish to simulate and estimate its duration until eukaryogenesis. Rough quantitation of its parameters shows that the model may explain the long duration of the Lucacene. [ABSTRACT FROM AUTHOR]