We discuss various aspects of high resolution measurements of phase fluctuations at microwave frequencies. This includes methods to achieve thermal noise limited sensitivity, along with the improved immunity to oscillator amplitude noise. A few prototype measurement systems were developed to measure phase fluctuations of microwave signals extracted from the optical pulse trains generated by femtosecond lasers. This enabled first reliable measurements of the excess phase noise associated with optical-to-microwave frequency division. The spectral density of the excess phase noise was found to be -140 dBc/Hz at 100 Hz offset from the 10 GHz carrier which was almost 40 dB better than that of a high quality microwave synthesizer.
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http://dx.doi.org/10.1109/tuffc.2007.307 | DOI Listing |
PLoS One
January 2025
Cnooc Information Technology Co., Ltd., Shenzhen, Guangdong, China.
A data transmission delay compensation algorithm for an interactive communication network of an offshore oil field operation scene in severe weather is proposed. To solve the problem of unstable microwave signals and a large amount of noise in the communication network caused by bad weather, the communication network signal denoising method based on Lagrange multiplier symplectic singular value mode decomposition is adopted, and the communication network data denoising process is realized through five steps; phase space reconstruction, symplectic geometric similarity transformation, grouping, diagonal averaging, and adaptive reconstruction. Simultaneously, the weak communication signal is compensated after being captured, that is, the characteristics of the weak signal are enhanced.
View Article and Find Full Text PDFSci Rep
January 2025
THz-Photonics Group, Institut für Hochfrequenztechnik, Technische Universität Braunschweig, 38106, Braunschweig, Germany.
Space division multiplexing (SDM) with Hermite Gaussian (HG) modes, for instance, can significantly boost the transmission link capacity. However, SDM is not suitable in existing single mode fiber networks, and in long-distance wireless, microwave, THz or optical links, the far-field beam distribution may present a problem. Recently it has been demonstrated, that time domain HG modes can be employed to enhance the link capacity.
View Article and Find Full Text PDFNat Commun
January 2025
State Key Laboratory for Extreme Photonics and Instrumentation, Center for Optical & Electromagnetic Research, College of Optical Science and Engineering, International Research Center for Advanced Photonics (Haining), Zhejiang University, Hangzhou, China.
Silicon photonic signal processors promise a new generation of signal processing hardware with significant advancements in processing bandwidth, low power consumption, and minimal latency. Programmable silicon photonic signal processors, facilitated by tuning elements, can reduce hardware development cycles and costs. However, traditional programmable photonic signal processors based on optical switches face scalability and performance challenges due to control complexity and transmission losses.
View Article and Find Full Text PDFInt J Nanomedicine
January 2025
Key Laboratory of Medical Cell Biology, Affiliated Hospital of Inner Mongolia Medical University, Hohhot, Inner Mongolia, People's Republic of China.
Introduction: The anti-cancer properties of zinc oxide-doped carbon dots (CDs/ZnO) in inhibiting triple-negative breast cancer (TNBC) progression merit more investigation.
Methods: With citric acid as the carbon source, urea applied as the nitrogen source, and zinc oxide (ZnO) used as a reactive dopant, CDs/ZnO were synthesized by microwave heating in the current study, followed by the characterization and biocompatibility assessments. Subsequently, the anti-cancer capabilities of CDs/ZnO against TNBC progression were evaluated by various biochemical and molecular techniques, including viability, proliferation, migration, invasion, adhesion, clonogenicity, cell cycle distribution, apoptosis, redox homeostasis, metabolome, and transcriptome assays of MDA-MB-231 cells.
Phytomedicine
December 2024
College of Food Science and Technology, Zhejiang University of Technology, Hangzhou, 310014, China. Electronic address:
Background: Gut dysbiosis, chronic diseases, and microbial recurrent infections concerns have driven the researchers to explore phytochemicals from medicinal and food homologous plants to modulate gut microbiota, mitigate diseases, and inhibit pathogens. Gingerols have attracted attention as therapeutic agents due to their diverse biological activities like gut microbiome regulation, gastro-protective, anti-inflammatory, anti-microbial, and anti-oxidative effects.
Purpose: This review aimed to summarize the gingerols health-promoting potential, specifically focusing on the regulation of gut microbiome, attenuation of disease symptoms, mechanisms of action, and signaling pathways involved.
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