X-ray speckle visibility spectroscopy using X-ray free-electron lasers has long been proposed as a probe of fast dynamics in noncrystalline materials. In this paper, numerical modeling is presented to show how the data interpretation of visibility spectroscopy can be impacted by the nonidealities of real-life X-ray detectors. Using simulated detector data, this work provides a detailed analysis of the systematic errors of several contrast extraction algorithms in the context of low-count-rate X-ray speckle visibility spectroscopy and their origins are discussed. Here, it was found that the finite detector charge cloud and pixel size lead to an unavoidable `degeneracy' in photon position determination, and that the contrasts extracted using different algorithms can all be corrected by a simple linear model. The results suggest that experimental calibration of the correction coefficient at the count rate of interest is possible and essential. This allows computationally lightweight algorithms to be implemented for on-the-fly analysis.
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http://dx.doi.org/10.1107/S1600577520006773 | DOI Listing |
Anal Chem
January 2025
School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, Heilongjiang150090, P. R. China.
Newborn screening for acylcarnitine-related inherited metabolic diseases (IMDs) is a critical test after birth. Conventional extraction methods require shaking with heating, centrifugation, nitrogen blowing, redissolution, etc., and the total time is more than 1 h.
View Article and Find Full Text PDFNat Commun
January 2025
Interdisciplinary Science Center, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 100101, Beijing, China.
Fluorogenic RNA aptamers have various applications, including use as fluorescent tags for imaging RNA trafficking and as indicators of RNA-based sensors that exhibit fluorescence upon binding small-molecule fluorophores in living cells. Current fluorogenic RNA:fluorophore complexes typically emit visible fluorescence. However, it is challenging to develop fluorogenic RNA with near-infrared (NIR) fluorescence for in vivo imaging and sensing studies.
View Article and Find Full Text PDFAnal Chim Acta
January 2025
College of Resources and Environment, Southwest University, Chongqing, 400716, China; Key Laboratory of Biomedical Analytics (Southwest University), Chongqing Science and Technology Bureau, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, China. Electronic address:
Background: Because arsenate (As(V)) is a highly toxic pollutant, timely on-site monitoring of its concentration is crucial for mitigating potential environmental and health hazards. Traditional on-site detection methods for As(V) often face limitations of long response time and low sensitivity. Nanozymes are nanomaterials that exhibit enzyme-like catalytic activity.
View Article and Find Full Text PDFAnal Chim Acta
January 2025
The Education Ministry Key Laboratory of Resource Chemistry, Joint International Research Laboratory of Resource Chemistry, Ministry of Education, Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Municipal Education Committee Key Laboratory of Molecular Imaging Probes and Sensors, Shanghai Frontiers Science Center of Biomimetic Catalysis and College of chemistry and materials science, School of Environmental and Geographical Sciences. Shanghai Normal University, Shanghai, 200234, People's Republic of China. Electronic address:
Background: Polycyclic aromatic hydrocarbons (PAHs) are one of the most dangerous persistent organic pollutants in the environment. Due to the discharge of chemical plants and domestic water, the existence of PAHs in sea water and lake water is harmful to human health. A method for rapid detection and removal of PAHs in water needs to be developed.
View Article and Find Full Text PDFJ Phys Chem B
January 2025
Department of Life Science and Applied Chemistry, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan.
The light-harvesting pigment-protein complex II (LHCII) from plants can be used as a component for biohybrid photovoltaic devices, acting as a photosensitizer to increase the photocurrent generated when devices are illuminated with sunlight. LHCII is effective at photon absorption in the red and blue regions of the visible spectrum, however, it has low absorption in the green region (550-650 nm). Previous studies have shown that synthetic chromophores can be used to fill this spectral gap and transfer additional energy to LHCII, but it was uncertain whether this would translate into an improved performance for photovoltaics.
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