In cellulo serial crystallography of alcohol oxidase crystals inside yeast cells

The possibility of using femtosecond pulses from an X-ray free-electron laser to collect diffraction data from protein crystals formed in their native cellular organelle has been explored. X-ray diffraction of submicrometre-sized alcohol oxidase crystals formed in peroxisomes within cells of genetically modified variants of the methylotrophic yeast Hansenula polymorpha is reported and characterized. The observations are supported by synchrotron radiation-based powder diffraction data and electron microscopy. Based on these findings, the concept of in cellulo serial crystallography on protein targets imported into yeast peroxisomes without the need for protein purification as a requirement for subsequent crystallization is outlined

Isotopic control of the boron-vacancy spin defect in hexagonal boron nitride

We report on electron spin resonance (ESR) spectroscopy of boron-vacancy (V$_\text{B}^-$) centers hosted in isotopically-engineered hexagonal boron nitride (hBN) crystals. We first show that isotopic purification of hBN with $^{15}$N yields a simplified and well-resolved hyperfine structure of V$_\text{B}^-$ centers, while purification with $^{10}$B leads to narrower ESR linewidths. These results establish isotopically-purified h$^{10}$B$^{15}$N crystals as the optimal host material for future use of V$_\text{B}^-$ spin defects in quantum technologies. Capitalizing on these findings, we then demonstrate optically-induced polarization of $^{15}$N nuclei in h$^{10}$B$^{15}$N, whose mechanism relies on electron-nuclear spin mixing in the V$_\text{B}^-$ ground state. This work opens up new prospects for future developments of spin-based quantum sensors and simulators on a two-dimensional material platform.Comment: 6 pages, 3 figur

Encountering religious diversity : multilevel governance of Islamic education in Finland and Ireland

Recent decades have witnessed a change in European governments’ policies from benign neglect to active management of religious diversity, where Islam is often seen as the most challenging for the European social order. However, the ways that this “management” is justified and undertaken varies from country to country and depends on the issues at hand. This paper will take up the issue of Islamic education in Finland and Ireland where it is incorporated into the public school system and where the state has taken an active role in order to control Islam in the field of education. The main argument of this article is that the “management” of Islamic education in both of the above-mentioned countries is ridden with contradictions arising from the difficulty to balance between an emphasis on particular national traditions, on the one hand, and public policies concerning religious diversity, on the other hand. Theoretically, the article will employ the perspective of multilevel governance which helps to widen the perspective from the state as a primary explanatory to different agents of the civil society in encountering religious diversity.Peer reviewe

Mémoire à consulter et consultation : délits de presse.

Signed: L.H. Moulin.At head of title: Cour d'assises de la Seine ... aud. du 15 juill."Caption title; imprint from colophon.Bound with: Acte d'accusation -- Plaidoyer de M. Doublet pour messieurs Guyot-Durepaire et Mounier, officiers de l'ex-Garde royale -- Procès de Prospert, ouvrier tailleur, et de Laporte, vermicellier.Mode of access: Internet

In situ observation of ferromagnetic order breaking in MnAs/GaAs(001) and magnetocrystalline anisotropy of α -MnAs by electron magnetic chiral dichroism

International audienceWe report an in situ observation of temperature-dependent phase transition in MnAs thin film by transmission electron microscopy (TEM) techniques. Following the identification of the crystallographic transition, from hexagonal α-MnAs to quasihexagonal β-MnAs, the orbital-to-spin moment ratio is measured and a breaking of the ferromagnetic order locally observed, thanks to the electron magnetic chiral dichroism (EMCD) technique. To achieve quantitative information, applying the sum rules to the dichroic signal of magnetic anisotropic materials is accurately discussed. Finally, the orbital-to-spin moment ratio of α-MnAs along the easy, hard, and intermediate magnetic axes is estimated by EMCD and compared to implemented density functional theory (DFT) calculations. The influence of the magnetocrystalline anisotropy is locally demonstrated. This work in particular illustrates the feasibility of the EMCD technique for in situ experiments, and proves its potential to explore the anisotropy of magnetic materials

Mecanismes regissant l'activite cancerogene de diverses poussieres inorganiques (amiante, certains composes de Fer, du Nickel, du Chrome)

CNRS RP 185 (1459) / INIST-CNRS - Institut de l'Information Scientifique et TechniqueSIGLEFRFranc

Methodes de calcul appliquees en aerodynamique transsonique

SIGLECNRS-CDST / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc