Source-Channel Diversity for Parallel Channels

We consider transmitting a source across a pair of independent, non-ergodic channels with random states (e.g., slow fading channels) so as to minimize the average distortion. The general problem is unsolved. Hence, we focus on comparing two commonly used source and channel encoding systems which correspond to exploiting diversity either at the physical layer through parallel channel coding or at the application layer through multiple description source coding. For on-off channel models, source coding diversity offers better performance. For channels with a continuous range of reception quality, we show the reverse is true. Specifically, we introduce a new figure of merit called the distortion exponent which measures how fast the average distortion decays with SNR. For continuous-state models such as additive white Gaussian noise channels with multiplicative Rayleigh fading, optimal channel coding diversity at the physical layer is more efficient than source coding diversity at the application layer in that the former achieves a better distortion exponent. Finally, we consider a third decoding architecture: multiple description encoding with a joint source-channel decoding. We show that this architecture achieves the same distortion exponent as systems with optimal channel coding diversity for continuous-state channels, and maintains the the advantages of multiple description systems for on-off channels. Thus, the multiple description system with joint decoding achieves the best performance, from among the three architectures considered, on both continuous-state and on-off channels.Comment: 48 pages, 14 figure

Joint Packet Scheduling and Content-Aware Playout Control for Video Streaming over Wireless Links

Abstract — Media streaming over wireless links is a chal-lenging problem due to both the unreliable, time-varying nature of the wireless channel and the stringent delivery requirements of media traffic. In this paper, we use joint control of packet scheduling at the transmitter and content-aware playout at the receiver, so as to maximize the quality of media streaming over a wireless link. Our contributions are twofold. First, we formulate and study the problem of joint scheduling and playout control within a dynamic pro-gramming framework. Second, we propose a novel content-aware playout control, that takes into account the content of a video sequence, and in particular the motion characteristics of different scenes. We find that the joint scheduling and playout control can significantly improve the quality of the received video, at the expense of only a small amount of playout slowdown. Furthermore, thanks to the content-aware playout, the slowdown takes place mainly in the low-motion scenes, where its perceived effect is limited. Index Terms — Video-Aware Adaptation and Communica

Polarized light therapy: shining a light on the mechanism underlying its immunomodulatory effects

This study investigates the immunomodulatory effects of polychromatic polarized light therapy (PLT) on human monocyte cells. While there is some evidence demonstrating a clinical effect in the treatment of certain conditions, there is little research into its mechanism of action. Herein, U937 monocyte cells were cultured and exposed to PLT. The cells were then analyzed for change in expression of genes and cell surface markers relating to inflammation. It was noted that 6 hours of PLT reduced the expression of the CD14, MHC I and CD11b receptors, and increased the expression of CD86. It was also shown that PLT caused downregulation of the genes IL1B, CCL2, NLRP3 and NOD1, and upregulation of NFKBIA and TLR9. These findings imply that PLT has the capacity for immunomodulation in human immune cells, possibly exerting an anti-inflammatory effect

The effect of low-level red and near-infrared photobiomodulation on pain and function in tendinopathy: a systematic review and meta-analysis of randomized control trials

Background: Tendinopathy is a common clinical condition that can significantly affect a person’s physical function and quality of life. Despite exercise therapy being the mainstay of tendinopathy management, there are many potential adjunct therapies that remain under investigated, one of which is photobiomodulation (PBM). PBM uses varied wavelengths of light to create a biological effect. While PBM is used frequently in the management of tendinopathy, high quality evidence supporting its utility is lacking. Methods: A systematic search of the Pubmed, CINAHL, SCOPUS, Cochrane Database, Web of Science and SPORTSDICUS databases was performed for eligible articles in August 2020. Randomized Control Trials that used red or near-infrared PBM to treat tendinopathy disorders that made comparisons with a sham or ‘other’ intervention were included. Pain and function data were extracted from the included studies. The data were synthesized using a random effects model. The meta-analysis was performed using the mean difference (MD) and standardized mean difference (SMD) statistics. Results: A total of 17 trials were included (n = 835). When compared solely to other interventions PBM resulted in similar decreases in pain (MD -0.09; 95% CI − 0.79 to 0.61) and a smaller improvement in function (SMD -0.52; 95% CI − 0.81 to − 0.23). When PBM plus exercise was compared to sham treatment plus exercise, PBM demonstrated greater decreases in pain (MD 1.06; 95% CI 0.57 to 1.55) and improved function (MD 5.65; 95% CI 0.25 to 11.04). When PBM plus exercise was compared to other interventions plus exercise, no differences were noted in pain levels (MD 0.31; 95% CI − 0.07 to 0.70). Most studies were judged as low-risk of bias. The outcome measures were classified as very low to moderate evidence quality according to the Grading of Recommendation, Development and Evaluation tool. Conclusion: There is very-low-to-moderate quality evidence demonstrating that PBM has utility as a standalone and/or adjunctive therapy for tendinopathy disorders. Trial registration: PROPERO registration number: CRD42020202508

The effect of low-level red and near-infrared photobiomodulation on pain and function in tendinopathy: a systematic review and meta-analysis of randomized control trials

Background: Tendinopathy is a common clinical condition that can significantly affect a person’s physical function and quality of life. Despite exercise therapy being the mainstay of tendinopathy management, there are many potential adjunct therapies that remain under investigated, one of which is photobiomodulation (PBM). PBM uses varied wavelengths of light to create a biological effect. While PBM is used frequently in the management of tendinopathy, high quality evidence supporting its utility is lacking. Methods: A systematic search of the Pubmed, CINAHL, SCOPUS, Cochrane Database, Web of Science and SPORTSDICUS databases was performed for eligible articles in August 2020. Randomized Control Trials that used red or near-infrared PBM to treat tendinopathy disorders that made comparisons with a sham or ‘other’ intervention were included. Pain and function data were extracted from the included studies. The data were synthesized using a random effects model. The meta-analysis was performed using the mean difference (MD) and standardized mean difference (SMD) statistics. Results: A total of 17 trials were included (n = 835). When compared solely to other interventions PBM resulted in similar decreases in pain (MD -0.09; 95% CI − 0.79 to 0.61) and a smaller improvement in function (SMD -0.52; 95% CI − 0.81 to − 0.23). When PBM plus exercise was compared to sham treatment plus exercise, PBM demonstrated greater decreases in pain (MD 1.06; 95% CI 0.57 to 1.55) and improved function (MD 5.65; 95% CI 0.25 to 11.04). When PBM plus exercise was compared to other interventions plus exercise, no differences were noted in pain levels (MD 0.31; 95% CI − 0.07 to 0.70). Most studies were judged as low-risk of bias. The outcome measures were classified as very low to moderate evidence quality according to the Grading of Recommendation, Development and Evaluation tool. Conclusion: There is very-low-to-moderate quality evidence demonstrating that PBM has utility as a standalone and/or adjunctive therapy for tendinopathy disorders. Trial registration: PROPERO registration number: CRD42020202508

The impact of motivational interviewing on behavioural change and health outcomes in cancer patients and survivors. A systematic review and meta-analysis

Background: Cancer patients and survivors commonly have poorer health behaviours and subsequent outcomes, often as a result of negative impacts of diagnosis and treatment. Motivational interviewing is reported to be an effective psychological tool to produce a shift in one's behaviour resulting in improved outcomes. However, there is a lack of analyses investigating this tool's impact on healthy behaviours and health outcomes in cancer populations. Objective: To investigate the effect of motivational interviewing on behaviours and health outcomes in cancer populations. Methods: The studies were identified from four databases using variations of the terms “cancer” and “motivational interviewing”. Randomised trials, non-randomised trials and quasi-experimental studies which contained control (or usual care) comparators were included. Risk of bias was assessed using the Cochrane Risk of Bias Version 5.1.0 and the Risk of Bias In Non-Randomised Studies of Interventions tools. The quality of evidence was assessed using the GRADE framework. Means difference and standardised mean differences and 95 % confidence intervals were used to report the pooled effects using a random effects model. Results: Twenty-one studies were included in the review and 17 studies were included in the meta-analysis. A total of 1752 cancer patients and survivors received MI as an intervention (or part thereof). Quality of life, anxiety, depression, functional tasks (6-minute walk test), body mass index and body weight (BMI/BW), physical activity (PA), self-efficacy and fatigue were outcomes measured in the selected studies. Effects were seen in functional tasks, physical activity, BMI/BW, depression and self-efficacy. All of these outcomes were from studies that were classed as very low-quality evidence except for BMI/BW and PA, which were from moderate-quality evidence. Conclusion: Motivational interviewing had positive effects on functional tasks, PA, BMI/BW, depression and self-efficacy in people diagnosed with cancer. However, more higher-quality studies need to be conducted to further ascertain the effect of this intervention

Convalescent plasma in patients admitted to hospital with COVID-19 (RECOVERY): a randomised controlled, open-label, platform trial

SummaryBackground Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatoryactions. We aimed to evaluate the safety and efficacy of azithromycin in patients admitted to hospital with COVID-19.Methods In this randomised, controlled, open-label, adaptive platform trial (Randomised Evaluation of COVID-19Therapy [RECOVERY]), several possible treatments were compared with usual care in patients admitted to hospitalwith COVID-19 in the UK. The trial is underway at 176 hospitals in the UK. Eligible and consenting patients wererandomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once perday by mouth or intravenously for 10 days or until discharge (or allocation to one of the other RECOVERY treatmentgroups). Patients were assigned via web-based simple (unstratified) randomisation with allocation concealment andwere twice as likely to be randomly assigned to usual care than to any of the active treatment groups. Participants andlocal study staff were not masked to the allocated treatment, but all others involved in the trial were masked to theoutcome data during the trial. The primary outcome was 28-day all-cause mortality, assessed in the intention-to-treatpopulation. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936.Findings Between April 7 and Nov 27, 2020, of 16 442 patients enrolled in the RECOVERY trial, 9433 (57%) wereeligible and 7763 were included in the assessment of azithromycin. The mean age of these study participants was65·3 years (SD 15·7) and approximately a third were women (2944 [38%] of 7763). 2582 patients were randomlyallocated to receive azithromycin and 5181 patients were randomly allocated to usual care alone. Overall,561 (22%) patients allocated to azithromycin and 1162 (22%) patients allocated to usual care died within 28 days(rate ratio 0·97, 95% CI 0·87–1·07; p=0·50). No significant difference was seen in duration of hospital stay (median10 days [IQR 5 to >28] vs 11 days [5 to >28]) or the proportion of patients discharged from hospital alive within 28 days(rate ratio 1·04, 95% CI 0·98–1·10; p=0·19). Among those not on invasive mechanical ventilation at baseline, nosignificant difference was seen in the proportion meeting the composite endpoint of invasive mechanical ventilationor death (risk ratio 0·95, 95% CI 0·87–1·03; p=0·24).Interpretation In patients admitted to hospital with COVID-19, azithromycin did not improve survival or otherprespecified clinical outcomes. Azithromycin use in patients admitted to hospital with COVID-19 should be restrictedto patients in whom there is a clear antimicrobial indication

An Investigation Into The Role Of Aldehyde Dehydrogenase 3a1 (aldh3a1) In The Mouse Cornea

Purpose: ALDH3A1 is a corneal crystallin that causes a profound retardation in cell proliferation, decreased light scattering in vitro and protection against oxidative stress. Corneal injury decreases ALDH3A1 and triggers cell proliferation and the development of corneal haze due to increase light scattering. Our congenic Aldh3a1 knockout mice exhibit corneal haze. Our aim was to validate a recently generated Aldh3a1 knock-in (KI) mouse model, allowing us to study the non-catalytic functions of ALDH3A1, and to identify new pathways associated with ALDH3A1 using transcriptome analysis. Methods: Western blot and enzyme activity for ALDH3A1 was performed to validate Aldh3a1 KI mouse model and RNA-seq analysis was performed in 3-6 month old WT and Aldh3a1 KO mice (N=4 per genotype). Differentially expressed genes in KO mice were identified as those with a minimum fold-change of +/− 2 and a Benjamini-Hochberg corrected p-value ≤0.05 relative to WT mice. Ingenuity® Pathway Analysis was used for pathway analyses. Results: ALDH3A1 was expressed in Aldh3a1 KI mice, but found to be catalytically inactive, validating our model. In addition, RNA-seq analyses revealed 334 differentially regulated genes in Aldh3a1 KO mouse corneas, of which 73 are upregulated and 261 are downregulated (p \u3c 0.05). Pathway analyses revealed neuroinflammation as the most activated pathway in Aldh3a1 KO mice, whereas inhibition of angiogenesis by TSP1 was the most inhibited pathway. Conclusions: Our results extend our previous studies and support our hypotheses in demonstrating that ALDH3A1 may modulate lens cataractogenesis, corneal transparency, and corneal epithelium homeostasis by regulating cell cycle and metabolism. In addition, by influencing neuroinflammation and angiogenesis, ALDH3A1 may also have an important role in corneal susceptibility to bacterial/parasitic infections and corneal vascularization during graft-versus-host disease