Antiferromagnetic ordering and uncoupled spins in CaFe2O4 thin films probed by spin Hall-magnetoresistance measurements

CaFe2O4 is a uniaxial antiferromagnet displaying two coexisting magnetic orderings, A and B, characterized by up-down-up-down and up-up-down-down spin modulation, respectively, and the emergence of a net magnetization in a limited temperature range, which is not yet understood. We investigate the angular dependent magnetoresistance (ADMR) at the interface between Pt and CaFe2O4 and exploit the crystallographic domain structure of thin film samples to probe the spin Hall magnetoresistance (SMR) at a single- and multi-domain scale. Upon rotation of the magnetic field along three orthogonal planes, we observe a sinusoidal modulation of the magnetoresistance indicating that the mechanism for SMR is the rotation of the spins, despite the strong magnetocrystalline and shape anisotropies. This, together with the study of the magnetic field dependence of the response, allows us to extract two contributions to the SMR: one corresponds to the long-range antiferromagnetic ordering, supporting a single ground state scenario. The second contribution originates from uncompensated and uncoupled spins. These are expected to exist at the antiphase boundaries between antiferromagnetic domains. Here we show that these are uncoupled from the antiferromagnetic ordering. Nonetheless, the long range correlations that emerge in the proximity of the critical antiferromagnetic transition could give rise to ordering of the uncompensated spins and be responsible for the net magnetization observed in this antiferromagnet

dataset of 'Electric control of optically-induced magnetization dynamics in a van der Waals ferromagnetic semiconductor'

This .zip archive contains all raw data used for the paper 'Electric control of optically-induced magnetization dynamics in a van der Waals ferromagnetic semiconductor'. In addition, it contains (partially) processed data, and the data that is plotted in the figures of this paper

CSD 2041937: Experimental Crystal Structure Determination

Related Article: Liliia D. Kulish, Pavan Nukala, Rick Scholtens, A. G. Mike Uiterwijk, Ruben Hamming-Green, Graeme R. Blake|2021|J.Mater.Chem.C|9|1370|doi:10.1039/D0TC05396

Supplementary material from "Controlled fluorescence in a beetle's photonic structure and its sensitivity to environmentally induced changes"

The scales covering the elytra of the male Hoplia coerulea beetle contain fluorophores embedded within a porous photonic structure. The photonic structure controls both insect colour (reflected light) and fluorescence emission. Herein, the effects of water-induced changes on the fluorescence emission from the beetle were investigated. The fluorescence emission peak wavelength was observed to blue-shift on water immersion of the elytra whereas its reflectance peak wavelength was observed to red-shift. Time-resolved fluorescence measurements, together with optical simulations, confirmed that the radiative emission is controlled by a naturally engineered photonic bandgap while the elytra are in the dry state, whereas non-radiative relaxation pathways dominate the emission response of wet elytra

Source data for the publication: Nanomagnetic Elastomers for Realizing Highly Responsive Micro- and Nanosystems

This data set contains the source data of the publication: Venkataramanachar, B.B., Li, J., Islam, T.U., Wang, Y. and den Toonder, J.M.J, 2023. Nanomagnetic Elastomers for Realizing Highly Responsive Micro-and Nanosystems. Nano Letters, 23(20), pp.9203-9211.https://doi.org/10.1021/acs.nanolett.3c00819. In this study, a material preparation process is reported that yields a library of nanomagnetic elastomers with high magnetic particle concentrations suitable for fabricating highly compliant submicron magnetic structures. The data are experimentally obtained with methods described in the publication

Radiation-induced synthetic lethality: combination of poly(ADP-ribose) polymerase and RAD51 inhibitors to sensitize cells to proton irradiation

Although improvements in radiation therapy were made over the years, radioresistance is still a major challenge. Cancer cells are often deficient for DNA repair response, a feature that is currently exploited as a new anti-cancer strategy. In this context, combination of inhibitors targeting complementary pathways is of interest to sensitize cells to radiation. In this work, we used PARP (Olaparib) and RAD51 (B02) inhibitors to radiosensitize cancer cells to proton and X-ray radiation. More particularly, Olaparib and B02 were used at concentration leading to limited cytotoxic (alone or in combination) but increasing cell death when the cells were irradiated. We showed that, although at limited concentration, Olaparib and B02 were able to radiosensitize different cancer cell lines, i.e. lung and pancreatic cancer cells. Antagonistic, additive or synergistic effects were observed and correlated to cell proliferation rate. The inhibitors enhanced persistent DNA damage, delayed apoptosis, prolonged cell cycle arrest and senescence upon irradiation. These results demonstrated that radiation-induced synthetic lethality might widen the therapeutic window, hence extending the use of PARP inhibitors to patients without BRCAness

Additional file 2: of Subchronic exposure to titanium dioxide nanoparticles modifies cardiac structure and performance in spontaneously hypertensive rats

Figure S2. TEM analysis of the alveolar lung parenchyma from a SHR rat seven weeks after intratracheal instillation of TiO2-NPs. Individual or microaggregates of small electrondense NPs are present in the air space (As) as scattered within the alveolar septum in which a type II pneumocyte (PII) is recognized. NPs are also apparent in endothelial cells lining a capillary (*) and the lumen of a larger venule containing red blood cells (RBC) polymorphonuclear (PMN) neutrophils, lymphocytes (Lym) and platelets (arrow). Magnification 1800X. Scale Bar: 10Îźm. (PDF 2011 kb

Additional file 1: of Subchronic exposure to titanium dioxide nanoparticles modifies cardiac structure and performance in spontaneously hypertensive rats

Figure S1. Spontaneous arrhythmic events. Different examples of arrhythmic events. Both, supraventricular (Supraventricular Extrasystole and Sinus Arrhythmia, SVA; Sinus Pause, SP) and ventricular (Atrio-ventricular block, AV block; Ventricular Extrasystole, VE) events were recorded. (PDF 324 kb

Subchronic exposure to titanium dioxide nanoparticles modifies cardiac structure and performance in spontaneously hypertensive rats

BACKGROUND: Non-communicable diseases, intended as the results of a combination of inherited, environmental and biological factors, kill 40 million people each year, equivalent to roughly 70% of all premature deaths globally. The possibility that manufactured nanoparticles (NPs) may affect cardiac performance, has led to recognize NPs-exposure not only as a major Public Health concern, but also as an occupational hazard. In volunteers, NPs-exposure is problematic to quantify. We recently found that inhaled titanium dioxide NPs, one of the most produced engineered nanomaterials, acutely increased cardiac excitability and promoted arrhythmogenesis in normotensive rats by a direct interaction with cardiac cells. We hypothesized that such scenario can be exacerbated by latent cardiovascular disorders such as hypertension. RESULTS: We monitored cardiac electromechanical performance in spontaneously hypertensive rats (SHRs) exposed to titanium dioxide NPs for 6 weeks using a combination of cardiac functional measurements associated with toxicological, immunological, physical and genetic assays. Longitudinal radio-telemetry ECG recordings and multiple-lead epicardial potential mapping revealed that atrial activation times significantly increased as well as proneness to arrhythmia. At the third week of nanoparticles administration, the lung and cardiac tissue encountered a maladaptive irreversible structural remodelling starting with increased pro-inflammatory cytokines levels and lipid peroxidation, resulting in upregulation of the main pro-fibrotic cardiac genes. At the end of the exposure, the majority of spontaneous arrhythmic events terminated, while cardiac hemodynamic deteriorated and a significant accumulation of fibrotic tissue occurred as compared to control untreated SHRs. Titanium dioxide nanoparticles were quantified in the heart tissue although without definite accumulation as revealed by particle-induced X-ray emission and ultrastructural analysis. CONCLUSIONS: The co-morbidity of hypertension and inhaled nanoparticles induces irreversible hemodynamic impairment associated with cardiac structural damage potentially leading to heart failure. The time-dependence of exposure indicates a non-return point that needs to be taken into account in hypertensive subjects daily exposed to nanoparticles

CCDC 2097729: Experimental Crystal Structure Determination

Related Article: Maite Perfecto-Irigaray, Garikoitz Beobide, Sofia Calero, Oscar Castillo, Ivan da Silva, J. José Gutierrez Sevillano, Antonio Luque, Sonia Pérez-Yáñez, Leticia F. Velasco|2021|Inorg.Chem.Front.|8|4767|doi:10.1039/D1QI00997