Joint Channel Probing and Proportional Fair Scheduling in Wireless Networks

The design of a scheduling scheme is crucial for the efficiency and user-fairness of wireless networks. Assuming that the quality of all user channels is available to a central controller, a simple scheme which maximizes the utility function defined as the sum logarithm throughput of all users has been shown to guarantee proportional fairness. However, to acquire the channel quality information may consume substantial amount of resources. In this work, it is assumed that probing the quality of each user's channel takes a fraction of the coherence time, so that the amount of time for data transmission is reduced. The multiuser diversity gain does not always increase as the number of users increases. In case the statistics of the channel quality is available to the controller, the problem of sequential channel probing for user scheduling is formulated as an optimal stopping time problem. A joint channel probing and proportional fair scheduling scheme is developed. This scheme is extended to the case where the channel statistics are not available to the controller, in which case a joint learning, probing and scheduling scheme is designed by studying a generalized bandit problem. Numerical results demonstrate that the proposed scheduling schemes can provide significant gain over existing schemes.Comment: 26 pages, 8 figure

Analgesic, anti-inflammatory and immuno-modulatory effects of dezocine-propofol anesthesia combination following colonoscopy

Purpose: To study and compare the analgesic, anti-inflammatory and immuno-modulatory effects of dezocine-propofol, and fentanyl-propofol combinations in colonoscopy.Methods: One hundred and thirty-four patients who received painless colonoscopy in Eastern Medical District of Linyi People's Hospital, Linyi City, Shandong Province, China, from June 2013 to December 2016 were randomly divided into two groups. Patients in the observation group (aged 42 - 65 years) received dezocine-propofol combination as anesthesia, while those in the control group (aged 41 - 67 years) were anesthetized with fentanyl-propofol. Serum levels of pain and inflammatory mediators, as well as contents of immune response molecules were determined prior to, during and after colonoscopy using either enzyme-linked immunosorbent assay (ELISA) or electro-chemiluminescence kits.Results: There were no statistically significant differences in the serum levels of 5-hydroxytryptophan (5-HTP), 5-hydroxy indole acetic acid (5-HIAA), substance P (SP), prostaglandin E2 (PGE2), C-reactive protein (CRP), heat shock protein 70 (HSP70), Interleukin-1 β(IL-1β), adrenocorticotropic hormone (ACTH), Cortisol (Cor), Inositol (Ins), c-peptide (C-P), immunoglobulin G (IgG) and immunoglobulin A (IgA), complement 3 (C3) and complement 4 (C4) before and during colonoscopy between the two groups of patients. However, after the examination, serum levels of 5-HTP, 5-HIAA, SP, PGE2, CRP, HSP70, IL-1 beta, ACTH, Cor, Ins and C-P in the observation group were significantly lower than those in control group (p < 0.05), while IgG, IgA, C3 and C4 contents were significantly higher than those of the control group (p < 0.05).Conclusion: These results suggest that the analgesic effect of dezocine-propofol combination after colonoscopy examination is superior to that of fentanyl-propofol combination, due to its effectiveness in inhibiting inflammatory reactions and improving immune response.Keywords: Colonoscopy, Dezocine, Propofol Fentanyl, Pain mediators, Analgesic, Inflammatory reaction, Immune respons