There are varied spin states in dilute magnetic semiconductors, and carriers are not the only elementary excitations that carry the spin. This article reports a study of spin interactions in excitons of ZnSe:NiI(II) nanostructures. High-quality ZnSe:NiI(II) nanobelts (NBs) prepared by chemical vapor deposition show a zinc blende structure by x-ray diffraction and Raman spectroscopy. The temperature-dependent photoluminescence spectra of doped NBs show independent free exciton (FX) and exciton magnetic polaron (EMP) peaks at room temperature with ferromagnetically coupled Ni ions. A single-mode lasing profile was obtained with femtosecond laser excitation due to condensation of EMPs over a threshold. The luminescence lifetimes at different pump powers indicated different relaxation profiles, confirming the formation of coherent EMP aggregates. At a slightly higher dopant concentration, a weak peak at the high-energy side of the FX peak showed up separately at low temperature; this should be the magnetic polaron emission band from the antiferromagnetically coupled Ni(II) pair binding with a FX (antiferromagnetic magnetic polaron). These results illustrate the typical spectroscopic characteristics of spin-spin magnetic coupling, exciton-spin or phonon interactions in dilute magnetic semiconductor nanostructures, showing that their different coupled spin types could work as exciton binders for their collective excitons, with possible use in spin nanophotonic devices and quantum modulations.
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http://dx.doi.org/10.1088/1361-6528/ab7cec | DOI Listing |
Clin Chem Lab Med
January 2025
70777 TUBITAK National Metrology Institute (TUBITAK UME), Kocaeli, Türkiye.
Objectives: An analytical protocol based on isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS), which includes a peptide-based calibration strategy, was developed and validated for the determination of cardiac troponin I (cTnI) levels in clinical samples. Additionally, the developed method was compared with a protein-based calibration strategy, using cTnI serving as a model for low-abundant proteins. The aim is to evaluate new approaches for protein quantification in complex matrices, supporting the metrology community in implementing new methods and developing fit-for-purpose SI- traceable peptide or protein primary calibrators.
View Article and Find Full Text PDFAm Heart J
December 2024
Department of cardiology, Guy's and St Thomas' NHS Foundation Trust, Harefield Hospital, London, UK; King's College London, London, UK.
Background: ST-segment elevation myocardial infarction (STEMI) is treated with immediate primary percutaneous coronary intervention (pPCI) to restore coronary blood flow in the acutely ischaemic territory, but is associated with reperfusion injury limiting the benefit of the therapy. No treatment has proven effective in reducing reperfusion injury. Transcoronary hypothermia has been tested in clinical studies and is well tolerated, but is generally established after crossing the occlusion with a guidewire therefore after initial reperfusion, which might have contributed to the neutral outcomes.
View Article and Find Full Text PDFJ Integr Neurosci
December 2024
Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT 06519, USA.
Background: The National Institutes of Health (NIH) Toolbox Cognition Battery is increasingly being used as a standardized test to examine cognitive functioning in multicentric studies. This study examines the associations between the NIH Toolbox Cognition Battery composite scores with neuroimaging metrics using data from the Adolescent Brain Cognitive Development (ABCD) study to elucidate the neurobiological and neuroanatomical correlates of these cognitive scores.
Methods: Neuroimaging data from 5290 children (mean age 9.
Malar J
December 2024
Institute of Tropical Medicine, Eberhard Karls University of Tübingen, Tübingen, Germany.
Background: Molecular methods play an important role in clinical trials assessing anti-malarial drugs and vaccines, as well as in epidemiological studies aimed at detecting Plasmodium species, especially when dealing with large sample sizes. Molecular techniques are more sensitive and generally have a higher throughput compared to the gold standard microscopy. Further optimization can be achieved with automation of nucleic acid isolation, allowing for rapid and precise extraction.
View Article and Find Full Text PDFACS Meas Sci Au
December 2024
Department of Chemistry, Oklahoma State University, Stillwater, Oklahoma 74078, United States.
This article presents a colorimetric visual biosensor designed for direct application in undiluted biofluids, which holds significant promise for point-of-need applications. Unlike traditional biosensors that struggle with heavily diluted sample matrices, the presented biosensor does not require any instrumentation or trained personnel, making it highly practical. The sensor features an oligonucleotide probe covalently attached to magnetically separable magnetite (FeO) particles.
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