Search results for " REM"
showing 10 items of 1460 documents
Chromatin remodeling regulation by small molecules and metabolites.
2010
The eukaryotic genome is a highly organized nucleoprotein structure comprising of DNA, histones, non-histone proteins, and RNAs, referred to as chromatin. The chromatin exists as a dynamic entity, shuttling between the open and closed forms at specific nuclear regions and loci based on the requirement of the cell. This dynamicity is essential for the various DNA-templated phenomena like transcription, replication, and repair and is achieved through the activity of ATP-dependent chromatin remodeling complexes and covalent modifiers of chromatin. A growing body of data indicates that chromatin enzymatic activities are finely and specifically regulated by a variety of small molecules derived f…
Multiple roles for ISWI in transcription, chromosome organization and DNA replication.
2003
ISWI functions as the ATPase subunit of multiple chromatin-remodeling complexes. These complexes use the energy of ATP hydrolysis to slide nucleosomes and increase chromatin fluidity, thereby modulating the access of transcription factors and other regulatory proteins to DNA. Here we discuss recent progress toward understanding the biological functions of ISWI, with an emphasis on its roles in transcription, chromosome organization and DNA replication.
Abscisic acid and desiccation-dependent expression of a novel putative SNF5-type chromatin-remodeling gene in Pisum sativum.
2006
Snf5-like proteins are components of multiprotein chromatin remodeling complexes involved in the ATP-dependent alteration of DNA-histone contacts. Mostly described in yeast and animals, the only plant SNF5-like gene characterized so far has been BSH from Arabidopsis thaliana (L.) Heynh. We report the cloning and characterization of expression of a SNF5-like gene from pea (Pisum sativum L. cv. Lincoln), which has been designated PsSNF5. Southern analysis showed a single copy of the gene in the pea genome. The cDNA contained a 723bp open reading frame encoding a 240 amino acid protein of 27.4kDa with a potential nuclear localization signal. PsSNF5 protein sequence closely resembled BSH, with …
Partitioning study of polycyclic aromatic hydrocarbons between water and some selected water-insoluble phases
2007
An investigation on the partitioning of naphthalene and phenanthrene between water and some water-insoluble phases has been carried out by Uv-vis-NIR spectrophotometry. The analysis of the experimental results emphasized the role of intermolecular interactions and structural features of the hosting phases as driving forces of the partitioning of these polycyclic aromatic hydrocarbons. The critical comparison of the resulting distribution constants allowed to evaluate the potentials of some extracting phases to set up sensitive analytical methods and/or effective environment remediation technologies.
Sediment diffusion method improves wastewater nitrogen removal in the receiving lake sediments
2018
Sediment microbes have a great potential to transform reactive N to harmless N2, thus decreasing wastewater nitrogen load into aquatic ecosystems. Here, we examined if spatial allocation of the wastewater discharge by a specially constructed sediment diffuser pipe system enhanced the microbial nitrate reduction processes. Full-scale experiments were set on two Finnish lake sites, Keuruu and Petäjävesi, and effects on the nitrate removal processes were studied using the stable isotope pairing technique. All nitrate reduction rates followed nitrate concentrations, being highest at the wastewater-influenced sampling points. Complete denitrification with N2 as an end-product was the main nitrat…
Optical remote sensing and the retrieval of terrestrial vegetation bio-geophysical properties – A review
2015
Abstract: Forthcoming superspectral satellite missions dedicated to land monitoring, as well as planned imaging spectrometers, will unleash an unprecedented data stream. The processing requirements for such large data streams involve processing techniques enabling the spatio-temporally explicit quantification of vegetation properties. Typically retrieval must be accurate, robust and fast. Hence, there is a strict requirement to identify next-generation bio-geophysical variable retrieval algorithms which can be molded into an operational processing chain. This paper offers a review of state-of-the-art retrieval methods for quantitative terrestrial bio-geophysical variable extraction using op…
Environmentally Friendly Eutectogels Comprising l-amino Acids and Deep Eutectic Solvents: Efficient Materials for Wastewater Treatment.
2020
Current concerns for sustainability and the environment make low-impact materials desirable for environmental remediation and, in particular wastewater treatment. We obtained supramolecular gels of l-amino acids in the deep eutectic solvent formed by choline chloride and phenylacetic acid. After gel characterization, and investigating gel-sol transition temperatures, gelation kinetics, rheological properties, and morphology, the gels were applied as sorbents to remove cationic dyes from aqueous solutions. The effects of the pH, dye nature, volume, and concentration of wastewater were analyzed, and the best result was obtained with a l-phenylalanine-based eutectogel. It can be reused for at …
High Nitrogen Removal in a Constructed Wetland Receiving Treated Wastewater in a Cold Climate
2018
Constructed wetlands provide cost-efficient nutrient removal, with minimal input of human labor and energy, and their number is globally increasing. However, in northern latitudes, wetlands are rarely utilized, because their nutrient removal efficiency has been questioned due to the cold climate. Here, we studied nutrient retention and nitrogen removal in a boreal constructed wetland (4-ha) receiving treated nitrogen-rich wastewater. On a yearly basis, most of the inorganic nutrients were retained by the wetland. The highest retention efficiency was found during the ice-free period, being 79% for ammonium-nitrogen (NH4+-N), 71% for nitrate-nitrogen (NO3--N), and 88% for phosphate-phosphorus…
Nitrous oxide emission in a University of Cape Town membrane bioreactor: The effect of carbon to nitrogen ratio
2017
Abstract The effect of the carbon-to-nitrogen (C/N) ratio in the influent on the nitrous oxide (N 2 O) emission from a University of Cape Town Membrane BioReactor pilot plant was investigated. The membrane was located in a separate tank to single out the production of N 2 O due to the biological processes from N 2 O stripping as a result of the extra aeration needed for the mitigation of membrane fouling. The experimental campaign was divided into two phases, each characterized by a different C/N ratio (namely, 10 and 5 mgCOD/mgTN, Phase I and Phase II, respectively). The decrease of the C/N ratio promoted the increase of N 2 O emissions in both gaseous and dissolved phases, mainly due to a…
An advanced control strategy for biological nutrient removal in continuous systems based on pH and ORP sensors
2012
[EN] A fuzzy logic-based control system that uses low-cost sensors for controlling and optimizing the biological nitrogen removal in continuous systems has been developed. The novelty of this control system is the use of several pH, ORP, and dissolved oxygen (DO) sensors instead of on-line nitrogen sensors/analyzers. The nitrogen control system was developed and implemented in a UCT pilot plant fed with wastewater from a full-scale plant. The developed nitrification controller allows the effluent ammonium concentration to be maintained below the effluent criteria discharge with the minimum energy consumption. The denitrification process controller allows the energy consumption derived from …