Compressive Sensing for Feedback Reduction in MIMO Broadcast Channels

We propose a generalized feedback model and compressive sensing based opportunistic feedback schemes for feedback resource reduction in MIMO Broadcast Channels under the assumption that both uplink and downlink channels undergo block Rayleigh fading. Feedback resources are shared and are opportunistically accessed by users who are strong, i.e. users whose channel quality information is above a certain fixed threshold. Strong users send same feedback information on all shared channels. They are identified by the base station via compressive sensing. Both analog and digital feedbacks are considered. The proposed analog & digital opportunistic feedback schemes are shown to achieve the same sum-rate throughput as that achieved by dedicated feedback schemes, but with feedback channels growing only logarithmically with number of users. Moreover, there is also a reduction in the feedback load. In the analog feedback case, we show that the propose scheme reduces the feedback noise which eventually results in better throughput, whereas in the digital feedback case the proposed scheme in a noisy scenario achieves almost the throughput obtained in a noiseless dedicated feedback scenario. We also show that for a fixed given budget of feedback bits, there exist a trade-off between the number of shared channels and thresholds accuracy of the feedback SINR.Comment: Submitted to IEEE Transactions on Wireless Communications, April 200

Surfactant protein D inhibits HIV-1 infection of target cells via interference with gp120-CD4 interaction and modulates pro-inflammatory cytokine production

© 2014 Pandit et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Surfactant Protein SP-D, a member of the collectin family, is a pattern recognition protein, secreted by mucosal epithelial cells and has an important role in innate immunity against various pathogens. In this study, we confirm that native human SP-D and a recombinant fragment of human SP-D (rhSP-D) bind to gp120 of HIV-1 and significantly inhibit viral replication in vitro in a calcium and dose-dependent manner. We show, for the first time, that SP-D and rhSP-D act as potent inhibitors of HIV-1 entry in to target cells and block the interaction between CD4 and gp120 in a dose-dependent manner. The rhSP-D-mediated inhibition of viral replication was examined using three clinical isolates of HIV-1 and three target cells: Jurkat T cells, U937 monocytic cells and PBMCs. HIV-1 induced cytokine storm in the three target cells was significantly suppressed by rhSP-D. Phosphorylation of key kinases p38, Erk1/2 and AKT, which contribute to HIV-1 induced immune activation, was significantly reduced in vitro in the presence of rhSP-D. Notably, anti-HIV-1 activity of rhSP-D was retained in the presence of biological fluids such as cervico-vaginal lavage and seminal plasma. Our study illustrates the multi-faceted role of human SPD against HIV-1 and potential of rhSP-D for immunotherapy to inhibit viral entry and immune activation in acute HIV infection. © 2014 Pandit et al.The work (Project no. 2011-16850) was supported by Medical Innovation Fund of Indian Council of Medical Research, New Delhi, India (www.icmr.nic.in/)

Clinical value of chest pain presentation and prodromes on the assessment of cardiovascular disease: a cohort study

The study was funded by a grant from the Worshipful Company of Curriers Millenium Bursary Fund

Acupuncture for cancer pain in adults.

BACKGROUND: Forty percent of individuals with early or intermediate stage cancer and 90% with advanced cancer have moderate to severe pain and up to 70% of patients with cancer pain do not receive adequate pain relief. It has been claimed that acupuncture has a role in management of cancer pain and guidelines exist for treatment of cancer pain with acupuncture. OBJECTIVES: To evaluate efficacy of acupuncture for relief of cancer-related pain in adults. SEARCH STRATEGY: CENTRAL, MEDLINE, EMBASE, PsycINFO, AMED, and SPORTDiscus were searched up to November 2010 including non-English language papers. SELECTION CRITERIA: Randomised controlled trials (RCTs) evaluating any type of invasive acupuncture for pain directly related to cancer in adults of 18 years or over. DATA COLLECTION AND ANALYSIS: It was planned to pool data to provide an overall measure of effect and to calculate the number needed to treat to benefit, but this was not possible due to heterogeneity. Two review authors (CP, OT) independently extracted data adding it to data extraction sheets. Quality scores were given to studies. Data sheets were compared and discussed with a third review author (MJ) who acted as arbiter. Data analysis was conducted by CP, OT and MJ. MAIN RESULTS: Three RCTs (204 participants) were included. One high quality study investigated the effect of auricular acupuncture compared with auricular acupuncture at 'placebo' points and with non-invasive vaccaria ear seeds attached at 'placebo' points. Participants in two acupuncture groups were blinded but blinding wasn't possible in the ear seeds group because seeds were attached using tape. This may have biased results in favour of acupuncture groups. Participants in the real acupuncture group had lower pain scores at two month follow-up than either the placebo or ear seeds group.There was high risk of bias in two studies because of low methodological quality. One study comparing acupuncture with medication concluded that both methods were effective in controlling pain, although acupuncture was the most effective. The second study compared acupuncture, point-injection and medication in participants with stomach cancer. Long-term pain relief was reported for both acupuncture and point-injection compared with medication during the last 10 days of treatment. Although both studies have positive results in favour of acupuncture they should be viewed with caution due to methodological limitations, small sample sizes, poor reporting and inadequate analysis. AUTHORS' CONCLUSIONS: There is insufficient evidence to judge whether acupuncture is effective in treating cancer pain in adults

No increase in 6-week treatment effect of Mechanical Diagnosis and Therapy with the use of the LUMBOback in people with non-acute non-specific low back pain and a directional preference of extension: a pilot randomized controlled trial.

Objectives: To pilot the methods for a randomized controlled trial (RCT) to investigate whether the treatment effect of Mechanical Diagnosis and Therapy (MDT) is enhanced with the LUMOback. Design: Assessor blinded RCT with 3 and 6-week follow-ups. Setting: An outpatient clinic. Participants: Primary eligibility criteria were: a directional preference of lumbar extension, ≥18 years of age, and non-specific low back pain lasting for ≥1 month. ACCEPTED MANUSCRIPT 2 Interventions: The MDT group undertook extension exercises (10 reps/3h) and postural correction using a lumbar roll at home. The MDT+LUMOback group also wore the LUMOback daily, providing a vibration alert in a slouched posture. Main outcome measures: The Global Rating of Change Scale (GRCS) (0-6), recruitment rate per month, treatment sessions, compliance rate of wearing the LUMOback, participants’ adherence with treatment, dropout rate and the stage of the MDT program at six weeks. Results: Twenty-two participants were included for 20 months (a recruitment rate of 1.1 patients/month). Dropout rate was 9%. The mean (SD) of the GRCS of the MDT and MDT+LUMOback groups were 4.7 (0.8) and 4.7 (0.5) at the 3-week follow-up and were both 4.9 (0.5) at the 6-week follow-up. The patients undertook a mean of 6.7 sessions for six weeks and exercises with mean of 3.7 set/day in each group. The mean compliance rate of wearing the LUMOback was 88%. Nobody was discharged from the intervention with full recovery within six weeks. Conclusions: Data indicated a promising method for the full RCT, but a rationale for the full RCT was not justified. Clinical Trial Registration number: UMIN000018380 Contribution of paper It was the ultimate aim to investigate if the treatment effect of Mechanical Diagnosis and Therapy (MDT) could be enhanced with the use of real-time feedback with the LUMOback in patients with a directional preference of lumbar extension. Regarding the methodology to achieve that aim, recruitment of participants in multiple centers was considered necessary, because of the low recruitment rate in the current study. ACCEPTED MANUSCRIPT 3 However, further investigation in a multi-center trial using the current methods is not justified due to the lack of difference in the treatment effect of MDT within six weeks, with or without the use of the LUMOback for assisting postural correction. Keywords: back pain; exercise therapy; lumbosacral region; manipulative therapies; posture; proprioceptive feedbac

What dreams of electric sheep – analysing public perception of synthetic influencers

Synthetic Influencers are a relatively new kind of influencers who have been introduced online. They emulate human influencers with their massive online fanbases, use of selfies and opinions on current trends. As a technology innovation, prominent companies have shown interest in them, as have the audiences, apparently: Miquela Sousa, one of the more prominent synthetic influencers has over 3 million followers. The existence of these influencers raises complex and interesting questions about digital representation, power, and profit, anonymity and accountability. This thesis explores the domain of ‘synthetic influencers’ through the lens of panfictionality and posthumanism in order to determine the ways in which they are changing the sphere of digital culture, especially in terms of parasocial interactions with audiences. This research addresses the question of whether synthetic influencers have a similar impact on people as their human counterparts, and how audiences perceive them in today’s landscape. Further, this thesis analyses the terms currently being used to describe synthetic influencers and determine whether they are representative of them or not. The research focuses on specific influencer profiles and does a deep dive into the content that they post and the audience response they garner. For this purpose, two synthetic influencers and two human influencers have been selected based on similar niches that they represent, hence allowing for comparisons between the synthetic and human influencers through a combination of qualitative and quantitative methodology. Analysis of their content and the reaction of the audience towards them highlights the differences between synthetic and human influencers, thereby negating the idea that theories that have been predominantly used for humans in the digital space can also be applicable on them. This research thus aims to contribute towards future scholarship on this phenomenon and its social impact, and potentially provide a starting point for describing and developing truly artificially intelligent social media influencers.Mastergradsoppgave i digital kulturDIKULT350MAHF-DIKU

Multi-Method Assessment of Newcomer Settlement Experiences in Kitchener-Waterloo

Every day hundreds of newcomers begin a new life in Canada. Some are refugees fleeing persecution, others come to join family, and yet others (mostly the economic and independent categories) are seeking to make a better life for themselves. In all, since 2000 around 250,000 people have settled in Canada each year. Their backgrounds and personal histories may be widely different and each one’s experience on arrival is unique. The communities across Canada into which they integrate differ too in their character and in the manner in which they receive newcomers. For many new Canadians, there are, nevertheless, certain shared experiences, as they make a home for themselves in this country. They must find somewhere to live and a job, familiarize themselves with a different society and culture, make a new network of friends and acquaintances and often learn a new language. In the process, they may experience success—but also alienation, loneliness, frustration, xenophobia and racism. Refugees often face particular challenges in adapting partly because their arrival was not planned or a matter of choice, but a matter of survival. They may be deeply traumatized by their past experiences. They often arrive separated from their immediate families whom they have had to leave behind, perhaps in the country of origin or in a refugee camp elsewhere. This thesis is based on research on Afghan newcomer refugees in two second-tier Ontario cities—Kitchener and Waterloo. The study involves assessing the settlement challenges of a sub-population that I refer to as one the most vulnerable groups for they share characteristics that render them vulnerable—refugee newcomers from smaller ethnic groups that are visible and linguistic minorities. This research followed their everyday activity patterns for one week utilizing a novel form of passive tracking based on GPS technology and an internet based prompted recall diary system. The main question this thesis examines is how effective the service provision and social network systems in KW are in assisting refugee newcomers with their immediate and long term needs. This includes how the daily activity patterns of newcomers are influenced by the social system in which they interact with both strong ties—families, friends, ethnic groups, and weak ties—co-ethnic service providers, community and municipal services. It also provides an assessment of the specific barriers Afghan newcomer refugees face in their efforts to make their settlement a successful experience, and the alternatives they seek in an attempt to overcome these barriers. The research finds that for a number of reasons, such as language difficulty and issues related to using transportation, access to settlement services continues to be a key concern of this group of newcomers. The research reveals how various service barriers become interrelated; this is particularly evident in relation to the challenges posed by transportation and how this compounds problems with access to medical services

The systematic guideline review: method, rationale, and test on chronic heart failure

Background: Evidence-based guidelines have the potential to improve healthcare. However, their de-novo-development requires substantial resources-especially for complex conditions, and adaptation may be biased by contextually influenced recommendations in source guidelines. In this paper we describe a new approach to guideline development-the systematic guideline review method (SGR), and its application in the development of an evidence-based guideline for family physicians on chronic heart failure (CHF). Methods: A systematic search for guidelines was carried out. Evidence-based guidelines on CHF management in adults in ambulatory care published in English or German between the years 2000 and 2004 were included. Guidelines on acute or right heart failure were excluded. Eligibility was assessed by two reviewers, methodological quality of selected guidelines was appraised using the AGREE instrument, and a framework of relevant clinical questions for diagnostics and treatment was derived. Data were extracted into evidence tables, systematically compared by means of a consistency analysis and synthesized in a preliminary draft. Most relevant primary sources were re-assessed to verify the cited evidence. Evidence and recommendations were summarized in a draft guideline. Results: Of 16 included guidelines five were of good quality. A total of 35 recommendations were systematically compared: 25/35 were consistent, 9/35 inconsistent, and 1/35 un-rateable (derived from a single guideline). Of the 25 consistencies, 14 were based on consensus, seven on evidence and four differed in grading. Major inconsistencies were found in 3/9 of the inconsistent recommendations. We re-evaluated the evidence for 17 recommendations (evidence-based, differing evidence levels and minor inconsistencies) - the majority was congruent. Incongruity was found where the stated evidence could not be verified in the cited primary sources, or where the evaluation in the source guidelines focused on treatment benefits and underestimated the risks. The draft guideline was completed in 8.5 man-months. The main limitation to this study was the lack of a second reviewer. Conclusion: The systematic guideline review including framework development, consistency analysis and validation is an effective, valid, and resource saving-approach to the development of evidence-based guidelines