Publications associées à EPR and spectrophotometric studies of free radicals (O2.-, .OH, BPD-MA.-) and singlet oxygen (1O2) generated by irradiation of benzoporphyrin derivative monoacid ring A

Charge-Transfer States in Organic Nanowires

Charge separation processes in organic semiconductors play a pivotal role in diverse applications ranging from photovoltaics to photocatalysis. Understanding these mechanisms, particularly the role of hybrid charge-transfer (CT) states, is essential for ad ...

EPFL2024

Multimodal transcriptomic atlases of mouse spinal cord injury

Matthieu Pierre Gautier

A spinal cord injury (SCI) triggers a cascade of molecular and cellular responses involving inflammatory cell infiltration and cytokine release, apoptosis, demyelination, excitotoxicity, ischemia, and the formation of a fibrotic scar surrounded by an astro ...

EPFL2024

When Subtyping Constraints Liberate A Novel Type Inference Approach for First-Class Polymorphism

Lionel Emile Vincent Parreaux, Aleksander Slawomir Boruch-Gruszecki

Type inference in the presence of first-class or "impredicative" second-order polymorphism a la System F has been an active research area for several decades, with original works dating back to the end of the 80s. Yet, until now many basic problems remain ...

Assoc Computing Machinery2024

Reactivity of Cyanobacteria Metabolites with Ozone: Multicompound Competition Kinetics

Urs von Gunten

Cyanobacterial blooms occur at increasing frequency and intensity, notably in freshwater. This leads to the introduction of complex mixtures of their products, i.e., cyano-metabolites, to drinking water treatment plants. To assess the fate of cyano-metabol ...

Amer Chemical Soc2024

Influence of aerosol acidity and organic ligands on transition metal solubility and oxidative potential of fine particulate matter in urban environments

Gerhard Lammel, Athanasios Nenes

The adverse health effects of air pollution around the world have been associated with the inhalation of fine particulate matter (PM2.5). Such outcomes are thought to be related to the induction of oxidative stress due to the excess formation of reactive o ...

Elsevier2023

Evaluation of the role of superoxide radical as chain carrier for the formation of hydroxyl radical during ozonation

Gang Yu, Urs von Gunten, Yan Wang

Superoxide radicals (O-2(center dot-)) have been suggested as an important chain carrier in the radical chain reaction that promotes ozone (O-3) decomposition to hydroxyl radicals ((OH)-O-center dot) during ozonation. However, due to the difficulty in meas ...

PERGAMON-ELSEVIER SCIENCE LTD2023

Bacterial inactivation in sunlit surface waters is dominated by reactive species that emanate from the synergy between light, iron, and natural organic matter

César Pulgarin, Stefanos Giannakis, Jun Ma, Da Wang, Shuang Song

In this study, the synergistic and antagonistic effects of Fe species and coexisting natural organic matter (NOM) on the efficacy of solar light disinfection of water are investigated. Different initial iron species (Fe2+/Fe3+) and naturalorganic matter ty ...

Elsevier2023

Critical Review on Bromate Formation during Ozonation and Control Options for Its Minimization

Urs von Gunten

Ozone is a commonly applied disinfectant and oxidantin drinkingwater and has more recently been implemented for enhanced municipalwastewater treatment for potable reuse and ecosystem protection. Onedrawback is the potential formation of bromate, a possible ...

AMER CHEMICAL SOC2023

Detecting the metabolism of individual yeast mutant strain cells when aged, stressed or treated with antioxidants with diamond magnetometry

Mayeul Sylvain Chipaux

Free radicals play a key role in the ageing process. However, free radicals are small, reactive and short lived and thus challenging to measure. We utilize a new technique called diamond magnetometry for this pur-pose. We make use of nitrogen vacancy cente ...

ELSEVIER SCI LTD2023

Between the Pattern and the Type: A short parallel story

Vasileios Chanis

Historically speaking, the notion of the type was reintroduced to the larger architectural discourse as a direct consequence of the crisis of the Modern. The task of revisiting the forms of the past also dictated the return of architectural methods that ha ...

2023

Widespread detection of chlorine oxyacids in the Arctic atmosphere

Julia Schmale, Ivo Fabio Beck, Hélène Paule Angot

Observations are reported of HClO3 and HClO4 in the atmosphere and their widespread occurrence over the pan-Arctic during spring, providing further insights into atmospheric chlorine cycling in the polar environment. ...

Nature Portfolio2023

Regulation and function of a hemicleaved Activin-A processing intermediate in melanoma

Manon Bulliard

Activin-A is a Transforming Growth Factor-B (TGFB)-related cytokine that regulates various biological processes including cell proliferation and differentiation through autocrine, paracrine or endocrine signaling. Activin-A expression is upregulated in mul ...

EPFL2023

Hypervalent Iodine: New Reagents and Functionalization of Peptides

Eliott Hugo Joran Le Du

Alkynes are found in a multitude of natural or synthetic bioactive compounds. In addition to the capacity of these chemical motifs to impact the physicochemical properties of a molecule of interest, the well-established reactivity of alkynes makes them ide ...

EPFL2023

Impact of chlorination and ozonation of dissolved organic matter on its photo-induced production of long-lived photooxidants and excited triplet states

Silvio Canonica, Urs von Gunten, Stephanie Christa Remke, Joanna Maria Houska

Recent studies suggested that long-lived photooxidants (LLPO), which are reactive intermediates formed during irradiation of dissolved organic matter (DOM), may consist of phenoxyl radicals derived from phenolic moieties of the DOM. Besides the well-studie ...

PERGAMON-ELSEVIER SCIENCE LTD2023

Capturing Types

Martin Odersky, Ondrej Lhoták, Aleksander Slawomir Boruch-Gruszecki

Type systems usually characterize the shape of values but not their free variables. However, many desirable safety properties could be guaranteed if one knew the free variables captured by values. We describe CC

Assoc Computing Machinery2023

Probing Water Dissociation and Oxygen Replacement on Partially Oxygen-Covered Cu(111) by Reflection Absorption Infrared Spectroscopy

Rainer Beck, Harmina Vejayan, Mateusz Suchodol

The presence of chemisorbed oxygen on the Cu(111) surface is known to strongly reduce the activation barrier for water dissociation as compared to bare Cu(111). Here, we present direct experimental evidence for the hydrogen abstraction mechanism responsibl ...

2023

Influence of DNP Polarizing Agents on Biochemical Processes: TEMPOL in Transient Ischemic Stroke

Lara Buscemi Estefanell, Mor-Miri Mishkovsky, Mario Gaetano Lepore, Jean-Noël Hyacinthe, Thanh Phong Kevin Lê

Hyperpolarization of 13C by dissolution dynamic nuclear polarization (dDNP) boosts the sensitivity of magnetic resonance spectroscopy (MRS), making possible the monitoring in vivo and in real time of the biochemical reactions of exogenously infused 13C-lab ...

2023

Identifying the mediators of intracellular E. coli inactivation under UVA light: The (photo) Fenton process and singlet oxygen

César Pulgarin, Stefanos Giannakis

Solar disinfection (SODIS) was probed for its underlying mechanism. When Escherichia coli was exposed to UVA irradiation, the dominant solar fraction acting in SODIS process, cells exhibited a shoulder before death ensued. This profile resembles cell killi ...

PERGAMON-ELSEVIER SCIENCE LTD2022

Photochemical oxidation of phenols and anilines mediated by phenoxyl radicals in aqueous solution

Silvio Canonica, Urs von Gunten, Stephanie Christa Remke

Reactive intermediates formed upon irradiation of chromophoric dissolved organic matter (CDOM) contribute to the degradation of various organic contaminants in surface waters. Besides well-studied "short-lived" photo oxidants, such as triplet state CDOM (3 ...

PERGAMON-ELSEVIER SCIENCE LTD2022

Studies on Types: Dormitories

Estelle Lépine, Tiago André Pratas Borges, Anja Fröhlich, Vanessa Pointet

Concepts of type and typology are not specific to architecture. Rather they represent an interdisciplinary approach to ordering knowledge and gaining insight. In the field of architecture, the study of types and typology offers a didactic perspective that ...

EPFL Press2022