It is reported that reversible changes in the reflectivity of Bragg gratings can be induced by a change in the temperature of the grating (77 K < T < K). The changes have proved to be greater in highly doped Ge fibers than in standard fibers, whereas they could hardly be detected in hydrogenated fibers. The sign of the change for type I gratings was opposite that for type IIA gratings. The changes are likely due to a temperature-induced increase (or a decrease) in the amplitude of the refractive-index modulation. Possible mechanisms for these changes in modulation are discussed. Interestingly for the purpose of correcting data of isothermal accelerated aging experiments, a numerical relation that accounts for the temperature-induced changes in type I grating reflectivity is given.
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http://dx.doi.org/10.1364/ao.40.002632 | DOI Listing |
Sci Rep
January 2025
Istituto per la Protezione Sostenibile delle Piante, Consiglio Nazionale delle Ricerche, via Amendola 165/A, 70126, Bari, Italy.
Tomato spotted wilt virus (TSWV; Orthotospovirus tomatomaculae) is one of the major horticultural threats due to its worldwide distribution and broad host range. In Italy, TSWV is widely spread in tomato (Solanum lycopersicum) crops and causes severe yield losses. In the last decades, several tomato varieties carrying the Sw-5b gene for resistance to TSWV have been released.
View Article and Find Full Text PDFMol Psychiatry
January 2025
Department of Psychiatry, University of Oxford, Oxford, UK.
Cognitive and neural mechanisms underlying bipolar disorder (BD) and its treatment are still poorly understood. Here we examined the role of adaptations in risk-taking using a reward-guided decision-making task. We recruited volunteers with high (n = 40) scores on the Mood Disorder Questionnaire, MDQ, suspected of high risk for bipolar disorder and those with low-risk scores (n = 37).
View Article and Find Full Text PDFAnal Chim Acta
March 2025
Van't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, the Netherlands; Centre for Analytical Sciences Amsterdam, Science Park 904, 1098 XH, Amsterdam, the Netherlands. Electronic address:
Background: Persistent and mobile organic compounds (PMOC) are of great concern for water quality and human health. The recent improvement and availability of high-resolution mass spectrometry in combination with liquid chromatography have widely expanded the potential of analytical workflows for their detection and quantitation in water. Given their high polarity, the detection of some PMOC requires alternative techniques to reversed-phase chromatography, such as hydrophilic interaction liquid chromatography (HILIC) and supercritical fluid chromatography (SFC).
View Article and Find Full Text PDFFood Chem
January 2025
College of Food Science and Technology, Northwest University, Xi'an 710069, Shaanxi, China; Laboratory of Nutritional and Healthy Food-Individuation Manufacturing Engineering, Xi'an 710069, Shaanxi, China; Research Center of Food Safety Risk Assessment and Control, Xi'an 710069, Shaanxi, China. Electronic address:
Apple polyphenols (APP) can reduce obesity. However, the effects of APP on abdominal subcutaneous adipose tissue (aSAT) at metabolic level were unclear. In this study, 5-week APP intervenes were conducted on 10-week high-fat diet (HFD) feeding mice with doses of 200 and 500 mg/kg b.
View Article and Find Full Text PDFPhys Rev Lett
December 2024
Clermont INP, Institut Pascal, PHOTON-N2, Université Clermont Auvergne, CNRS, F-63000 Clermont-Ferrand, France.
The combination of an in-plane honeycomb potential and of a photonic spin-orbit coupling (SOC) emulates a photonic or polaritonic analog of bilayer graphene. We show that modulating the SOC magnitude allows us to change the overall lattice periodicity, emulating any type of moiré-arranged bilayer graphene with unique all-optical access to the moiré band topology. We show that breaking the time-reversal symmetry by an effective exciton-polariton Zeeman splitting opens a large topological gap in the array of moiré flat bands.
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