Removal of turbidity and organic load from surface water by coagulation-flotation

The aim of this study is to monitor comparatively and operationally two drinking water treatment flows, a new based on flotation unit using prehydrolyzed aluminium coagulation agent in comparison with settling based on the conventional technological flow using aluminium sulphate coagulation agent. The new proposed and introduced flow exhibited greater drinking water treatment performance under the conditions of raw surface water characterized by low and medium loading in terms of turbidity and organic load. The new proposed technological flow allowed that all studied parameters characteristics to the drinking water for treated water to meet the requirements imposed by the legislative norms

Size Doesn't Matter: Towards a More Inclusive Philosophy of Biology

notes: As the primary author, O’Malley drafted the paper, and gathered and analysed data (scientific papers and talks). Conceptual analysis was conducted by both authors.publication-status: Publishedtypes: ArticlePhilosophers of biology, along with everyone else, generally perceive life to fall into two broad categories, the microbes and macrobes, and then pay most of their attention to the latter. ‘Macrobe’ is the word we propose for larger life forms, and we use it as part of an argument for microbial equality. We suggest that taking more notice of microbes – the dominant life form on the planet, both now and throughout evolutionary history – will transform some of the philosophy of biology’s standard ideas on ontology, evolution, taxonomy and biodiversity. We set out a number of recent developments in microbiology – including biofilm formation, chemotaxis, quorum sensing and gene transfer – that highlight microbial capacities for cooperation and communication and break down conventional thinking that microbes are solely or primarily single-celled organisms. These insights also bring new perspectives to the levels of selection debate, as well as to discussions of the evolution and nature of multicellularity, and to neo-Darwinian understandings of evolutionary mechanisms. We show how these revisions lead to further complications for microbial classification and the philosophies of systematics and biodiversity. Incorporating microbial insights into the philosophy of biology will challenge many of its assumptions, but also give greater scope and depth to its investigations

Statistical Mechanics of Horizontal Gene Transfer in Evolutionary Ecology

The biological world, especially its majority microbial component, is strongly interacting and may be dominated by collective effects. In this review, we provide a brief introduction for statistical physicists of the way in which living cells communicate genetically through transferred genes, as well as the ways in which they can reorganize their genomes in response to environmental pressure. We discuss how genome evolution can be thought of as related to the physical phenomenon of annealing, and describe the sense in which genomes can be said to exhibit an analogue of information entropy. As a direct application of these ideas, we analyze the variation with ocean depth of transposons in marine microbial genomes, predicting trends that are consistent with recent observations using metagenomic surveys.Comment: Accepted by Journal of Statistical Physic

Complete parts and subhypergroups in reversible regular hypergroups

Abstract In this paper we analyse the center and centralizer of an element in the context of reversible regular hypergroups, in order to obtain the class equation in regular reversible hypergroups, by using complete parts. After an introduction in which basic notions and results of hypergroup theory are presented, particularly complete parts, then we give several properties, characterisations and also examples for the center and centralizer of an element for two classes of hypergroups. The next paragraph is dedicated to hypergroups associated with binary relations. We establish a connection between several types of equivalence relations, introduced by J. Jantosciak, such as the operational relation, the inseparability and the essential indistin-guishability and the conjugacy relation for complete hypergroups. Finally, we analyse Rosenberg hypergroup associated with a conjugacy relation.</jats:p

Arrays of Microscale Linear Ridges with Self-Cleaning Functionality for the Oxygen Evolution Reaction

The full text of this paper will be available in January, 2022 due to the embargo policies of ACS Applied Materials & Interfaces. Contact [email protected] to enquire if the full text of the accepted manuscript can be made available to you

2003b. Functional characterization of retina and optic nerve after acute ocular ischemia in rats

PURPOSE. To functionally characterize the status of the rat retina and optic nerve after acute elevation of intraocular pressure (IOP) and to determine the dynamics of the pathologic changes in the ischemic retina and optic nerve. METHODS. Retinal ischemia was induced in rats by acutely increasing the IOP (110 mm Hg/60 minutes). Direct and indirect pupil light reflexes (PLRs) were recorded from the noninjured eye, and electroretinograms (flash and flicker ERG) were recorded from the injured and control eyes before and after surgery. Amplitudes and latencies were calculated for each recording session. RESULTS. Preoperative PLR ratio s (indirect/direct PLR) were 76.7 Ϯ 2.6 (mean Ϯ SEM). Twenty-four hours after surgery the PLR ratio was 15.2 Ϯ 12.8, 10 days after surgery, 11.6 Ϯ 9.8; 20 days after surgery, 26.5 Ϯ 8.0; and 28 days after surgery, 33.27 Ϯ 9.3. However, at day 35, the PLR had significantly recovered (41.1 Ϯ 7.3) when compared with the 24-hour postoperative ratios (P Ͻ 0.01, repeated-measures ANOVA). Forty-two days after surgery, the PLR ratio started to decrease once again in the injured eyes (28.7 Ϯ 5.9). Electroretinographic amplitudes (full-field flash ERG) followed a similar pattern. Cone responses (flicker ERG) were measured 42 days after surgery and revealed defects in injured eyes (control eyes: 46.6 Ϯ 2.9 V, injured eyes: 3.4 Ϯ 1.7 V). Histologic analysis revealed ischemic damage to all retinal layers, with the primary defects localized to the central retina. CONCLUSIONS. Acute ocular ischemia causes a significant decrease in retinal function, as measured by PLR and ERG, although over time the rat retina and optic nerve show partial regain of function. (Invest Ophthalmol Vis Sci. 2003;44: 2597-2605) DOI:10.1167/iovs.02-0600 I schemic insults to the retina and optic nerve are frequently observed in glaucoma, acute ocular hypertension, diabetic retinopathy, hypertension, and vascular occlusion, and giant cell arteritis and can lead to serious perturbation of neuronal and glial retinal elements and can ultimately lead to blindness. Traditionally, retinal damage due to ischemia has been considered a potentially incurable condition in humans and animals because of the mammalian central nervous system has no regenerative capacity. Few reports have described the recovery of visual function in patients who have severe retinal ischemia after central retinal artery occlusion, 1,2 whereas more reports have confirmed that severe ischemic events are followed by almost complete and irreversible loss of visual function. 10,11 However, quantitative analysis of the damage has been achieved only by end-stage counting of the cells in the different retinal layers 12 or retrograde fluorescent labeling of retinal ganglion cells (RGCs). 13 Relatively few studies have included a functional analysis of the retina after ischemia-reperfusion injury using electroretinography (ERG) for a prolonged period, 14 -16 and, to our knowledge, there is only one published study that actually documents function of the retina and optic nerve in rats after ischemia-reperfusion injury (Clarke RJ, Gamlin PDR, ARVO Abstract 4593, 1998). Although morphologic studies provide important information about the number of surviving cells, only electrophysiological studies offer precise information about the functional status of the retina and the dynamics of ischemic injury. MATERIALS AND METHODS Induction of Retinal Ischemia by Elevated IOP All animal studies were conducted in accordance with the ARVO Statement for Use of Animals in Ophthalmic and Vision Research, and procedures were approved by the Iowa State University Committee on Animal Care. A previously published procedure to generate an ischemia-reperfusion insult in rats was used, with slight modification

How big is the iceberg of which organellar genes in nuclear genomes are but the tip?

As more and more complete bacterial and archaeal genome sequences become available, the role of lateral gene transfer (LGT) in shaping them becomes more and more clear. Over the long term, it may be the dominant force, affecting most genes in most prokaryotes. We review the history of LGT, suggesting reasons why its prevalence and impact were so long dismissed. We discuss various methods purporting to measure the extent of LGT, and evidence for and against the notion that there is a core of never-exchanged genes shared by all genomes, from which we can deduce the "true" organismal tree. We also consider evidence for, and implications of, LGT between prokaryotes and phagocytic eukaryotes