We experimentally demonstrate the enhancement of the spontaneous emission rate of GaAs quantum wells embedded in rolled-up metamaterials. We fabricate microtubes whose walls consist of alternating Ag and (In)(Al)GaAs layers with incorporated active GaAs quantum-well structures. By variation of the layer thickness ratio of the Ag and (In)(Al)GaAs layers we control the effective permittivity tensor of the metamaterial according to an effective medium approach. Thereby, we can design samples with elliptic or hyperbolic dispersion. Time-resolved low temperature photoluminescence spectroscopy supported by finite-difference time-domain simulations reveal a decrease of the quantum well's spontaneous emission lifetime in our metamaterials as a signature of the crossover from elliptic to hyperbolic dispersion.
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http://dx.doi.org/10.1103/PhysRevLett.117.085503 | DOI Listing |
Pain Rep
February 2025
Institute for Biomedical Sciences of Pain, Tangdu Hospital, The Fourth Military Medical University, Xi'an, P. R. China.
Objectives: This study is to assess how 22 kHz and 50 kHz spontaneous ultrasound vocalization (USV) calls would be affected by different origins of pain so as to validate the use of USV in pain studies.
Methods: Five well-established rat models of pain were used to evaluate various parameters of spontaneous 22 kHz and 50 kHz calls in adult male rats in terms of both acute and chronic or inflammatory and neuropathic or somatic and visceral origins. The effects of local lidocaine blockade of the injection site and intraperitoneal administration of antidepressant (amitriptyline) and anticonvulsant (gabapentin) were examined as well in typical inflammatory and neuropathic pain models, respectively.
J Phys Chem A
December 2024
Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, United States.
Highly energetic boron (B) particles embedded in hydroxyl-terminated polybutadiene (HTPB) thermosetting polymers represent stable solid-state fuel. Laser-heating of levitated B/HTPB and pure HTPB particles in a controlled atmosphere revealed spontaneous ignition of B/HTPB in air, allowing for examination of the exclusive roles of boron. These ignition events are probed via simultaneous spectroscopic diagnostics: Raman and infrared spectroscopy, temporally resolved high-speed optical and infrared cameras, and ultraviolet-visible (UV-vis) spectroscopy.
View Article and Find Full Text PDFRedox Biol
December 2024
Baruch College and CUNY Graduate Center, 1 Baruch Way, New York, NY, 10010, USA. Electronic address:
The elevated emission of reactive oxygen species (ROS) from presynaptic mitochondria is well-documented in several inflammatory and neurodegenerative diseases. However, the potential role of mitochondrial ROS in presynaptic function and plasticity remains largely understudied beyond the context of disease. Here, we investigated this potential ROS role in presynaptic function and short-term plasticity by combining optogenetics, whole cell electrophysiological recordings, and live confocal imaging using a well-established protocol for induction and measurement of synaptic potentiation in Drosophila melanogaster neuromuscular junctions (NMJ).
View Article and Find Full Text PDFJ Chem Phys
December 2024
Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan.
Based on our previous study [Wang et al., J. Chem.
View Article and Find Full Text PDFIsr Med Assoc J
December 2024
Department of Dermatology, Emek Medical Center, Afula, Israel.
Background: Little is known about audiovestibular function in psoriasis, a chronic systemic inflammatory disease that affects 2% of the world's population.
Objectives: To investigate audiovestibular function in patients with psoriasis.
Methods: In this prospective case-control trial, we enrolled 33 patients with psoriasis and 30 healthy controls.
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