Publications associées à Cycle du fer

The Mononuclear Metal-Binding Site of Mo-Nitrogenase Is Not Required for Activity

The biological N-2-fixation process is catalyzed exclusively by metallocofactor-containing nitrogenases. Structural and spectroscopic studies highlighted the presence of an additional mononuclear metal-binding (MMB) site, which can coordinate Fe in additio ...

Amer Chemical Soc2023

Multiphase processes in the EC-Earth model and their relevance to the atmospheric oxalate, sulfate, and iron cycles

Athanasios Nenes

Understanding how multiphase processes affect the iron-containing aerosol cycle is key to predicting ocean biogeochemistry changes and hence the feedback effects on climate. For this work, the EC-Earth Earth system model in its climate-chemistry configurat ...

COPERNICUS GESELLSCHAFT MBH2022

Oxidation of pyrite (FeS2) and troilite (FeS) impurities in kaolinitic clays after calcination

Karen Scrivener, Franco Alberto Zunino Sommariva

Valorisation of locally available clays for producing blended cements is crucial for a widespread adoption of sustainable binders incorporating these materials. In some places, clays can be intermixed with small amounts of iron sulfides, which could eventu ...

SPRINGER2022

Contrasting Microbiome Dynamics of Putative Denitrifying Bacteria in Two Octocoral Species Exposed to Dissolved Organic Carbon (DOC) and Warming

Nils Rädecker, Claudia Isabella Pogoreutz

Mutualistic nutrient cycling in the coral-algae symbiosis depends on limited nitrogen (N) availability for algal symbionts. Denitrifying prokaryotes capable of reducing nitrate or nitrite to dinitrogen could thus support coral holobiont functioning by limi ...

2022

Towards an improved understanding of biogeochemical processes across surface-groundwater interactions in intermittent rivers and ephemeral streams

Luis Gómez Gener, Oleksandra Shumilova

Surface-groundwater interactions in intermittent rivers and ephemeral streams (IRES), waterways which do not flow year-round, are spatially and temporally dynamic because of alternations between flowing, non-flowing and dry hydrological states. Interaction ...

2021

Diel quenching of Southern Ocean phytoplankton fluorescence is related to iron limitation

Nina Schuback

Evaluation of photosynthetic competency in time and space is critical for better estimates and models of oceanic primary productivity. This is especially true for areas where the lack of iron (Fe) limits phytoplankton productivity, such as the Southern Oce ...

2020

Electrochemical evaluation of iron-binding ligands along the Australian GEOTRACES southwestern Pacific section (GP13)

Christel Sybille Hassler

In this work, we performed electrochemical investigations of Fe-binding ligands in water samples collected in autumn 2011 along the Australian GEOTRACES southwestern Pacific section (GP13, between 153 degrees E and 170 degrees W longitude along the 30 degr ...

2020

Role of Iron Sulfide Phases in the Stability of Noncrystalline Tetravalent Uranium in Sediments

Rizlan Bernier-Latmani, Luca Loreggian

Uranium (U) in situ bioremediation has been investigated as a cost-effective strategy to tackle U contamination in the subsurface. While uraninite was believed to be the only product of bioreduction, numerous studies have revealed that noncrystalline U(IV) ...

AMER CHEMICAL SOC2020

The role of Organophosphate Esters Flame Retardants and plasticizers (OPEs) in Phosphorus Cycle in the atmosphere of the Mediterranean Sea

Athanasios Nenes, Kalliopi Violaki, Christos Panagiotopoulos

The atmosphere is considered as an important external nutrient source for the marine environment, especially in remote ocean waters or the oligotrophic Mediterranean Sea. Phosphorus (P) is a critical nutrient affecting primary productivity in large areas o ...

2020

Heterotrophic Foraminifera Capable of Inorganic Nitrogen Assimilation

Anders Meibom, Charlotte Madeleine Nicole Lekieffre, Emmanuelle Geslin

Nitrogen availability often limits biological productivity in marine systems, where inorganic nitrogen, such as ammonium is assimilated into the food web by bacteria and photoautotrophic eukaryotes. Recently, ammonium assimilation was observed in kleptopla ...

Frontiers Media SA2020

Nano-imaging trace elements at organelle levels in substantia nigra overexpressing alpha-synuclein to model Parkinson's disease

Bernard Schneider, Graham Knott, Philippe Colin

Sub-cellular trace element quantifications of nano-heterogeneities in brain tissues offer unprecedented ways to explore at elemental level the interplay between cellular compartments in neurodegenerative pathologies. We designed a quasi-correlative method ...

NATURE PUBLISHING GROUP2020

Ammonium is the preferred source of nitrogen for planktonic foraminifer and their dinoflagellate symbionts

Anders Meibom, Charlotte Madeleine Nicole Lekieffre, Emmanuelle Geslin

The symbiotic planktonic foraminiferaOrbulina universainhabits open ocean oligotrophic ecosystems where dissolved nutrients are scarce and often limit biological productivity. It has previously been proposed thatO. universameets its nitrogen (N) requiremen ...

ROYAL SOC2020

Mechanism(s) of electron transfer and metabolic changes during iron reduction by Clostridium acetobutylicum

Cornelia List

Microorganisms catalyze many of the redox transformations driving the iron cycle in the geosphere. For instance, iron cycling includes the reduction of solid-phase and soluble ferric iron (Fe(III)) to ferrous iron (Fe(II)). However, in order to reduce soli ...

EPFL2019

Impact of iron reduction on the metabolism of Clostridium acetobutylicum

Vassily Hatzimanikatis, Rizlan Bernier-Latmani, Karin Lederballe Meibom, Cornelia List, Zhaleh Hosseini

Iron is essential for most living organisms. In addition, its biogeochemical cycling influences important processes in the geosphere (e.g., the mobilization or immobilization of trace elements and contaminants). The reduction of Fe(III) to Fe(II) can be ca ...

2019

Enhancing solar disinfection of water in PET bottles by optimized in-situ formation of iron oxide films. From heterogeneous to homogeneous action modes with H2O2 vs. O-2 - Part 1: Iron salts as oxide precursors

César Pulgarin, Sami Rtimi, Stefanos Giannakis, Sakine Shekoohiyan

Solar disinfection (SODIS) is a WHO-accepted intervention method for improving water sources in developing countries. Despite its effectiveness, the limitations of long exposure and bacterial regrowth risk demand further improvement of the practice. In thi ...

ELSEVIER SCIENCE SA2019

Electronic Structure-Dependent Surface Plasmon Resonance in Single Au-Fe Nanoalloys

Olivier Martin, Duncan Thomas Lindsay Alexander, Jérémy Butet, Gabriel David Bernasconi

The relationship between composition and plasmonic properties in noble metal nanoalloys is still largely unexplored. Yet, nanoalloys of noble metals, such as gold, with transition elements, such as iron, have unique properties and a number of potential app ...

2019

Freeze-thaw cycles simultaneously decrease peatland photosynthetic carbon uptake and ecosystem respiration

Alexandre Buttler, Constant Signarbieux, Vincent Eric Jules Jassey, Mariusz Lamentowicz, Bjorn Jozef Maria Robroek, Robert Thomas Edmund Mills, Maaike Louise Hofsommer

Decreasing snow cover in winter resulting from climate warming increases the incidence of freeze-thaw cycles (FTCs) in many ecosystems, including peatlands. As peatland ecosystems form a globally significant long-term carbon storage, understanding the effe ...

Finnish Environment Inst2017

Recent Advances in the Synthesis and Applications of Multimodal Gold-Iron Nanoparticles

Francesco Stellacci

Bimetallic particles based on gold and iron have been gathering increasing interest in biomedical applications because of the synergic combination of the plasmonic features of the inert gold component with the magnetic properties of the iron or iron oxide ...

Bentham Science Publishers2017

Castles fall from inside: Evidence for dominant internal photo-catalytic mechanisms during treatment of Saccharomyces cerevisiae by photo-Fenton at near-neutral pH

César Pulgarin, Sami Rtimi, Stefanos Giannakis, Cristina del Socorro Lonfat

In this work, the antimicrobial effects of the photo-Fenton process on yeast cells were tested (Saccharomyces cerevisiae), an essential eukaryotic unicellular model of living cells. Near-neutral pH was used in all studies, while iron sulfate and iron citra ...

Elsevier2016

Principal parameters affecting virus inactivation by the solar photo-Fenton process at neutral pH and mu M concentrations of H2O2 and Fe2+/(3+)

César Pulgarin, Anna Carratala Ripolles

The inactivation of the coliphage MS2 (a human virus indicator) by solar photo-Fenton at near neutral pH in carbonate buffer solution matrix was evaluated. The effects of reactant concentration (H2O2, Fe2+, Fe3+) and solar irradiance on the photo-Fenton pr ...

2015