826 research outputs found
Acute Optic Neuritis: An Update on Approach and Management
This review discusses the physical examination and diagnostic tests necessary to diagnose optic neuritis (ON) and provides an update on the approach and management of acute ON. A comprehensive search of the PubMed database was conducted, limited to English-language journals and recent publications. A total of 160 articles were initially screened by title, of which 73 articles were included in the narrative synthesis. ON is an inflammation of the optic nerve that can be caused by different systemic and neurological disorders. It is commonly presented as a subacute unilateral painful vision loss, and based on its clinical manifestation, it can be classified as typical or atypical. Atypical ON is bilateral with visual acuity of worse than 20/200 or has an atypical demographic presentation for demyelination, such as a non-Caucasian male with optic disc swelling, for which neuromyelitis optica spectrum disorder (NMOSD), myelin-oligodendrocyte glycoprotein antibody-associated disease (MOGAD), or other etiologies should be considered. Steroids and immunosuppressants are the main treatment options for ON, and timely treatment initiation is critical to preventing irreversible vision loss, especially in atypical cases
Joint Data Routing and Power Scheduling for Wireless Powered Communication Networks
In a wireless powered communication network (WPCN), an energy access point
supplies the energy needs of the network nodes through radio frequency wave
transmission, and the nodes store the received energy in their batteries for
their future data transmission. In this paper, we propose an online stochastic
policy that jointly controls energy transmission from the EAP to the nodes and
data transfer among the nodes. For this purpose, we first introduce a novel
perturbed Lyapunov function to address the limitations on the energy
consumption of the nodes imposed by their batteries. Then, using Lyapunov
optimization method, we propose a policy which is adaptive to any arbitrary
channel statistics in the network. Finally, we provide theoretical analysis for
the performance of the proposed policy and show that it stabilizes the network,
and the average power consumption of the network under this policy is within a
bounded gap of the minimum power level required for stabilizing the network
- …