The influence of the ambient atmosphere on the dynamics of plasma expansion, besides the interaction between excited plasma and gas molecules, has been studied for specific organic aromatic compounds. To analyze the influence of air on the formation pathways of atomic and molecular species inside the plasma plume, the spectral emissions in laser-induced breakdown spectroscopy (LIBS) of 2,4,6-trinitrotoluene (TNT) and pyrene were compared at different pressure environments, from high vacuum to atmospheric pressure. Pelletized samples of the compounds were introduced in a vacuum chamber for excitation with the fourth harmonic output of an Nd : YAG laser (266 nm). The optical emission signal was collected with an optical fiber connected to a spectrograph fitted with a intensified charge-coupled device detector. Results from LIBS spectra indicate that changes in pressure level affect the kinetics of the characteristic excited species and their spatial distribution inside the plasma plume.
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http://dx.doi.org/10.1366/13-07164 | DOI Listing |
Adv Sci (Weinh)
January 2025
School of Integrated Circuits, Peking University, Beijing, 100871, China.
The efficient isolation and molecular analysis of circulating tumor cells (CTCs) from whole blood at single-cell level are crucial for understanding tumor metastasis and developing personalized treatments. The viability of isolated cells is the key prerequisite for the downstream molecular analysis, especially for RNA sequencing. This study develops a laser-induced forward transfer -assisted microfiltration system (LIFT-AMFS) for high-viability CTC enrichment and retrieval from whole blood.
View Article and Find Full Text PDFFoods
January 2025
Department of Physics, University of Patras, 26504 Patras, Greece.
The fast detection of Extra Virgin Olive Oil (EVOO) adulteration with poorer quality and lower price vegetable oils is important for the protection of consumers and the market of olive oil from fraudulent activities, the latter exhibiting an increasing trend worldwide during the last few years. In this work, two optical spectroscopic techniques, namely, Laser-Induced Breakdown Spectroscopy (LIBS) and UV-Vis-NIR absorption spectroscopy, are employed and are assessed for EVOO adulteration detection, using the same set of olive oil samples. In total, 184 samples were studied, including 40 EVOOs and 144 binary mixtures with pomace, soybean, corn, and sunflower oils, at various concentrations (ranging from 10 to 90% /).
View Article and Find Full Text PDFJ Hazard Mater
January 2025
College of Engineering and Technology, Southwest University, Chongqing 400716, PR China. Electronic address:
The detection of heavy metals in soil is of great scientific significance for food security and human health. However, traditional detection methods are complicated, time-consuming, and labor-intensive. Herein, we developed a novel method using Au@SiO nanoparticles (NPs) and surface microstructure combined with laser-induced breakdown spectroscopy (Au@SiO NPs-SMS-LIBS) for the rapid detection of lead (Pb), chromium (Cr), and copper (Cu) in soil samples.
View Article and Find Full Text PDFMol Med
January 2025
Research Institute, National Cancer Center, Goyang-Si, Gyeonggi-Do, 10408, Republic of Korea.
Background: Double-strand breaks (DSBs) are primarily repaired through non-homologous end joining (NHEJ) and homologous recombination (HR). Given that DSBs are highly cytotoxic, PARP inhibitors (PARPi), a prominent class of anticancer drugs, are designed to target tumors with HR deficiency (HRD), such as those harboring BRCA mutations. However, many tumor cells acquire resistance to PARPi, often by restoring HR in HRD cells through the inactivation of NHEJ.
View Article and Find Full Text PDFAnal Methods
January 2025
National Key Laboratory of Uranium Resources Exploration-Mining and Nuclear Remote Sensing, Beijing, 100029, China.
With the increasing demand for energy, nuclear energy has been developing rapidly. The quantitative detection and qualitative identification of uranium (U) are of great significance for the comprehensive and efficient use of U resources and the control of nuclear and radioactive substances. In this study, the detection of U is divided into liquid sample detection, solid sample detection, gas sample detection, and industrial detection from the perspectives of the sample state and detection environment.
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