We report on the first experimental observation of a current-driven instability developing in a quasineutral matter-antimatter beam. Strong magnetic fields (≥1 T) are measured, via means of a proton radiography technique, after the propagation of a neutral electron-positron beam through a background electron-ion plasma. The experimentally determined equipartition parameter of ε_{B}≈10^{-3} is typical of values inferred from models of astrophysical gamma-ray bursts, in which the relativistic flows are also expected to be pair dominated. The data, supported by particle-in-cell simulations and simple analytical estimates, indicate that these magnetic fields persist in the background plasma for thousands of inverse plasma frequencies. The existence of such long-lived magnetic fields can be related to analog astrophysical systems, such as those prevalent in lepton-dominated jets.
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http://dx.doi.org/10.1103/PhysRevLett.119.185002 | DOI Listing |
J Magn Reson Imaging
January 2025
Department of Radiology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, Jiangsu, China.
Background: At high magnetic fields, degraded image quality due to dielectric artifacts and elevated specific absorption rate (SAR) are two technical challenges in fetal MRI.
Purpose: To assess the potential of high dielectric constant (HDC) pad in increasing image quality and decreasing SAR for 3 T fetal MRI.
Study Type: Prospective.
Curr Res Microb Sci
December 2024
Material Resource Efficiency Division, CSIR-Indian Institute of Petroleum, Mohkampur, Dehradun 248005, Uttarakhand, India.
The challenges of pollution and agro-industrial waste management have led to the development of bioconversion techniques to transform these wastes into valuable products. This has increased the focus on the sustainable and cost-efficient production of biosurfactants from agro-industrial waste. Hence, the present study investigates the production of sophorolipid biosurfactants using the yeast strain IIPL32 under submerged fermentation, employing sugarcane bagasse hydrolysate-a renewable, low-cost agro-industrial waste as the feedstock.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Spine and Spinal Cord Surgery, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, People's Hospital of Henan University, No. 7 Weiwu Road, Jinshui District, Zhengzhou, 450003, Henan, China.
The use of pulsed electromagnetic field (PEMF) has demonstrated effectiveness in the management of femoral head osteonecrosis as well as nonunion fractures; however, the effects of PEMF on preventing glucocorticoid-induced osteoporosis (GIOP) have not been extensively studied. The aim of this investigation was to explore the effectiveness of PEMF stimulation in averting GIOP in rats and uncover the potential fundamental mechanisms involved. A total of seventy-two adult male Wistar rats composed the experimental group and were subsequently assigned to three groups for treatment.
View Article and Find Full Text PDFAJNR Am J Neuroradiol
January 2025
From the Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA, USA (Colin M Segovis), Department of Neuroradiology, University of Texas MD Anderson Cancer Center, Houston, Texas, USA (Jacob W Ormsby, Melissa M Chen), Department of Radiology, Indiana University School of Medicine, Indianapolis, IN, USA (Cindy X Yuan), Enterprise Radiology, Emory Healthcare, Atlanta, GA, USA (Matthew J Goette), Department of Radiology, Mayo Clinic, Rochester, MN, USA (Heidi A Edmonson).
The magnetic fields of the MR environment present unique safety challenges. Medical implants and retained foreign bodies can prevent patients from undergoing MR imaging due to interactions between the magnetic fields of the MR environment and the implant or foreign body. These hazards can be addressed through careful MR safety screening and MR examination customization, often allowing these patients with implants to undergo management-altering MR imaging.
View Article and Find Full Text PDFJ Food Sci
January 2025
Department of Human Nutrition, Food, and Animal Sciences, University of Hawai'i at Mānoa, Honolulu, Hawai'i, USA.
Freezing extends the shelf life of foods but often leads to structural damage due to ice crystal formation, negatively impacting quality attributes. Oscillating magnetic field (OMF)-assisted supercooling has emerged as a potential technique to overcome these limitations by inhibiting ice nucleation and maintaining foods in a supercooled state. Despite its potential, the effectiveness and underlying mechanisms of OMF-assisted supercooling remain subjects of debate.
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