We report on a Laser Induced Breakdown Spectroscopy (LIBS) system with a very high temporal resolution, using femtosecond and picosecond pulse laser excitation of pure aluminum (Al). By using a 140 fs Ti:Sapphire laser in an ultrafast optical Kerr gate (OKG), we demonstrate LIBS sampling with a sub-ps time resolution (0.8 ± 0.08 ps) in a 14 ns window. The width of the gating window in this system was as narrow as 0.8 ps, owing to the inclusion of a carbon disulfide (CS(2)) cell, which has a fast response and a large nonlinear coefficient. Furthermore, when using a 100 ps pulsed Nd:YAG laser and a fast photomultiplier tube (PMT) we demonstrate a LIBS system with a nanosecond time resolution (2.20 ± 0.08 ns) in a microsecond window. With this sort of temporal resolution, a non-continuous decay in the Al signal could be observed. After 50 ns decay of the first peak, the second peak at 230 ns is started to perform. Experimental results with such short temporal windows in LIBS, in both nanosecond and microsecond ranges, are important for fast temporal evolution measurements and observations of early continuum emission in materials.
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http://dx.doi.org/10.1364/OE.21.021579 | DOI Listing |
Neuroradiology
January 2025
Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China.
Introduction: Bipolar disorder (BD) and major depressive disorder (MDD) have overlapping clinical presentations which may make it difficult for clinicians to distinguish them potentially resulting in misdiagnosis. This study combined structural MRI and machine learning techniques to determine whether regional morphological differences could distinguish patients with BD and MDD.
Methods: A total of 123 participants, including BD (n = 31), MDD (n = 48), and healthy controls (HC, n = 44), underwent high-resolution 3D T1-weighted imaging.
Mol Ther
January 2025
Faculty of Biology, Medicine & Health, University of Manchester, Manchester, M13 9PT, UK. Electronic address:
Optogenetic therapy is a promising vision restoration method where light sensitive opsins are introduced to the surviving inner retina following photoreceptor degeneration. The cell type targeted for opsin expression will likely influence the quality of restored vision. However, a like-for-like pre-clinical comparison of visual responses evoked following equivalent opsin expression in the two major targets, ON bipolar (ON BCs) or retinal ganglion cells (RGCs), is absent.
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January 2025
Dipartimento di Scienze Biologiche, Geologiche ed Ambientali, Università di Bologna, Bologna, Italy.
Heterogeneous fault architecture affects crustal seismotectonics and fluid migration. When studying it, we commonly rely on static conceptual models that generally overlook the absolute time dimension of fault (re)activation. Heterogenous faults, however, represent the end-result of protracted, cumulative and intricate deformation histories.
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January 2025
University of Bern, Wyss Academy for Nature, Bern, 3011, Switzerland.
Throughout the last centuries, European climate changed substantially, which affected the potential to plant and grow crops. These changes happened not just over time but also had a spatial dimension. Yet, despite large climatic fluctuations, quantitative historical studies typically rely on static measures for agricultural suitability due to the non-availability of time-varying indices.
View Article and Find Full Text PDFACS Nano
January 2025
Research Laboratory of Electronics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
Understanding energy transport in semiconductors is critical for the design of electronic and optoelectronic devices. Semiconductor material properties, such as charge carrier mobility or diffusion length, are commonly measured in bulk crystals and determined using models that describe transport behavior in homogeneous media, where structural boundary effects are minimal. However, most emerging semiconductors exhibit nano- and microscale heterogeneity.
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