An ultra-long phase-sensitive optical time domain reflectometry (Φ-OTDR) that can achieve high-sensitivity intrusion detection over 131.5km fiber with high spatial resolution of 8m is presented, which is the longest Φ-OTDR reported to date, to the best of our knowledge. It is found that the combination of distributed Raman amplification with heterodyne detection can extend the sensing distance and enhances the sensitivity substantially, leading to the realization of ultra-long Φ-OTDR with high sensitivity and spatial resolution. Furthermore, the feasibility of applying such an ultra-long Φ-OTDR to pipeline security monitoring is demonstrated and the features of intrusion signal can be extracted with improved SNR by using the wavelet detrending/denoising method proposed.
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http://dx.doi.org/10.1364/OE.22.013804 | DOI Listing |
Proc Natl Acad Sci U S A
January 2025
Department of Environmental Health, Harvard T. H. Chan School of Public Health, Boston, MA 02114.
Radon, a common radioactive indoor air pollutant, is the second leading cause of lung cancer in the United States. Knowledge about its distribution is essential for risk assessment and designing efficient protective regulations. However, the three current radon maps for the United States are unable to provide the up-to-date, high-resolution, and time-varying radon concentrations.
View Article and Find Full Text PDFCurr Cardiol Rep
January 2025
Onassis Cardiac Surgery Center, Athens, Greece.
Purpose Of Review: Our purpose was to discuss the advantages and disadvantages of various noninvasive imaging modalities in the evaluation of cardiovascular disease (CVD) in patients with autoimmune rheumatic diseases (ARDs). The detailed knowledge of imaging modalities will facilitate the diagnosis and follow up of CVD in ARDs.
Recent Findings: Autoimmune Rheumatic Diseases (ARDs) are characterized by alterations in immunoregulatory system of the body.
Forensic Sci Med Pathol
January 2025
School of Biochemistry and Biotechnology, University of the Punjab, Lahore, Pakistan.
Matrix-assisted laser Desorption/Ionization Mass Spectrometry Imaging (MALDI MSI) is an analytical technique used for the spatial mapping of drugs, explosives, and organic samples, making it a game-changer in Forensic examination. It detects a wide range of biomolecules in their native state without specific tags, antibodies, labels, and dyes. This review aims to highlight the advancement of MALDI-MSI over time and its impact on Forensic Science due to high-resolution molecular imaging.
View Article and Find Full Text PDFSmall Methods
January 2025
College of Physics and Energy, Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, Fujian Normal University, Fuzhou, 350117, China.
The Solid Electrolyte Interphase (SEI) is a nanoscale thickness passivation layer that forms as a product of electrolyte decomposition through a combination of chemical and electrochemical reactions in the cell and evolves over time with charge/discharge cycling. The formation and stability of SEI directly determine the fundamental properties of the battery such as first coulombic efficiency (FCE), energy/power density, storage life, cycle life, and safety. The dynamic nature of SEI along with the presence of spatially inhomogeneous organic and inorganic components in SEI encompassing crystalline, amorphous, and polymeric nature distributed across the electrolyte to the electrolyte-electrode interface, highlights the need for advanced in situ/operando techniques to understand the formation and structure of these materials in creating a stable interface in real-world operating conditions.
View Article and Find Full Text PDFCancer Cell Int
January 2025
Department of Neurosurgery, The First Affiliated Hospital, Guangxi Medical University, Nanning, China.
The tertiary lymphoid structure (TLS) is recognized as a potential prognosis factor for breast cancer and is strongly associated with response to immunotherapy. Inducing TLS neogenesis can enhance the immunogenicity of tumors and improve the efficacy of immunotherapy. However, our understanding of TLS associated region at the single-cell level remains limited.
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