10,019 research outputs found

    Using Network Analysis to Understand Knowledge Mobilization in a Community-based Organization

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    Background Knowledge mobilization (KM) has been described as putting research in the hands of research users. Network analysis is an empirical approach that has potential for examining the complex process of knowledge mobilization within community-based organizations (CBOs). Yet, conducting a network analysis in a CBO presents challenges. Purpose The purpose of this paper is to demonstrate the value and feasibility of using network analysis as a method for understanding knowledge mobilization within a CBO by (1) presenting challenges and solutions to conducting a network analysis in a CBO, (2) examining the feasibility of our methodology, and (3) demonstrating the utility of this methodology through an example of a network analysis conducted in a CBO engaging in knowledge mobilization activities. Method The final method used by the partnership team to conduct our network analysis of a CBO is described. Results An example of network analysis results of a CBO engaging in knowledge mobilization is presented. In total, 81 participants completed the network survey. All of the feasibility benchmarks set by the CBO were met. Results of the network analysis are highlighted and discussed as a means of identifying (1) prominent and influential individuals in the knowledge mobilization process and (2) areas for improvement in future knowledge mobilization initiatives. Conclusion Findings demonstrate that network analysis can be feasibly used to provide a rich description of a CBO engaging in knowledge mobilization activities

    Agglomeration during spray drying: Air-borne clusters or breakage at the walls?

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    Particle agglomeration, wall deposition and resuspension are inherent to many industries and natural processes, and often inter-connected. This work looks into their relation in a confined particle laden swirling flow. It investigates how the size of detergent powder spray dried in a swirl counter-current tower responds to changes in the air flow. Four sets of sprays are investigated under varying combinations of air temperature and velocity that cause the same evaporation. The use of high air velocities accumulates more of the droplets and dry powder in the chamber swirling faster, but it leads to creation of a finer product. Particle-particle and particle-wall contacts are made more frequent and energetic but in turn the swirl troughs the solids to the wall where deposits constantly form and break. Past PIV and tracer studies revealed that the rates of deposition and resuspension are balanced; the data discussed here indicate that the dynamic nature of the deposits is a major contributor to particle formation. In contrast with the usual assumption, the product size seems driven not by inter-particle contacts in airborne state but the ability of the solids to gain kinetic energy and break up a collection of clusters layering on the wall. As a result, the dryer performance becomes driven by the dynamic of deposition and resuspension. This paper studies the efficiency of limiting operation strategies and shows that a low temperature design concept is better suited to control fouling phenomena and improve capacity and energy consumption

    Finite Element Modeling of Ultrasonic Waves Produced by a Pulsed Laser

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    As part of an effort to apply laser ultrasonics to stress evaluation, sequential thermal and mechanical finite element analyses were used to simulate heating a region of an aluminum surface by a laser pulse and the stress waves that result. As residual or applied stresses can be related to changes in wave velocities, time-of-flight measurements may be used to determine the stresses. The goal of the effort is to improve time-of-flight measurements, and therefore resolution of the calculated stresses, using calculated waveform shapes in model-based signal processing techniques [1]. Detailed finite element simulations of laser ultrasonics may also be used to aid development of techniques that can generate narrow band ultrasound. Because penetration of Rayleigh waves is frequency dependent, they can be used to obtain information about gradients near a surface. If the frequency of the laser generated Rayleigh waves can be controlled, laser ultrasound becomes a more useful tool for examining gradients in material properties or stresses at the surface of a part

    Flavor of quiver-like realizations of effective supersymmetry

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    We present a class of supersymmetric models which address the flavor puzzle and have an inverted hierarchy of sfermions. Their construction involves quiver-like models with link fields in generic representations. The magnitude of Standard-Model parameters is obtained naturally and a relatively heavy Higgs boson is allowed without fine tuning. Collider signatures of such models are possibly within the reach of LHC in the near future.Comment: LaTeX, 17 pages, 3 figures. V2: reference adde

    Prevalence of HIV Infection in Pulmonary Tuberculosis Suspects; Assessing the Nnamdi Azikiwe University Teaching Hospital, Nnewi, Nigeria

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    After decades of decline, TB made a dramatic comeback, a situation largely fuelled by the emergence of the HIV pandemic, amongst other factors, including overcrowding, poverty and weak health care system. HIV/TB co-infection, presently poses serious public health challenges especially in the African region, including Nigeria. The aim of this study was to determine the prevalence of HIV amongst PTB suspects in Nnewi, Nigeria. A total of 1544 pulmonary TB suspects assessing the Nnamdi Azikiwe University Teaching Hospital Nnewi who were screened for TB using  Ziehl Neelsen Sputum smear microscopy were also subjected to HIV counseling and testing (HCT). Of the 1544 PTB suspects 184 (11.9%) reacted to HIV antibodies with a higher frequency in the females (13.3%) than the males (10.4%). Total of 237 (15.4%) of the 1544 suspects had pulmonary TB infection with the prevalence being higher in the males (19.9%) than in the females (11.2%). A total of 22 (1.42%) were HIV/TB co-infected, with the males (1.6%) having a slightly higher frequency than the females (1.2%). The age distributions showed that the age groups of 31-40 and 41-50 years had the highest frequencies for HIV and TB infections in this study. The infection rate was lower among participants below 20 and above 60 years of age. More accurate method of detecting TB may be applied in future work to help understand the real burden of TB amongst HIV patients. Keywords: HIV and Pulmonary Tuberculosi

    A Two-Tier Golgi-Based Control of Organelle Size Underpins the Functional Plasticity of Endothelial Cells

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    Weibel-Palade bodies (WPBs), endothelial-specific secretory granules that are central to primary hemostasis and inflammation, occur in dimensions ranging between 0.5 and 5 μm. How their size is determined and whether it has a functional relevance are at present unknown. Here, we provide evidence for a dual role of the Golgi apparatus in controlling the size of these secretory carriers. At the ministack level, cisternae constrain the size of nanostructures (“quanta”) of von Willebrand factor (vWF), the main WPB cargo. The ribbon architecture of the Golgi then allows copackaging of a variable number of vWF quanta within the continuous lumen of the trans-Golgi network, thereby generating organelles of different sizes. Reducing the WPB size abates endothelial cell hemostatic function by drastically diminishing platelet recruitment, but, strikingly, the inflammatory response (the endothelial capacity to engage leukocytes) is unaltered. Size can thus confer functional plasticity to an organelle by differentially affecting its activities

    Dietary interventions for recurrent abdominal pain in childhood

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    This is the final version of the article. Available from Wiley via the DOI in this record.BACKGROUND: This is an update of the original Cochrane review, last published in 2009 (Huertas-Ceballos 2009). Recurrent abdominal pain (RAP), including children with irritable bowel syndrome, is a common problem affecting between 4% and 25% of school-aged children. For the majority of such children, no organic cause for their pain can be found on physical examination or investigation. Many dietary inventions have been suggested to improve the symptoms of RAP. These may involve either excluding ingredients from the diet or adding supplements such as fibre or probiotics. OBJECTIVES: To examine the effectiveness of dietary interventions in improving pain in children of school age with RAP. SEARCH METHODS: We searched CENTRAL, Ovid MEDLINE, Embase, eight other databases, and two trials registers, together with reference checking, citation searching and contact with study authors, in June 2016. SELECTION CRITERIA: Randomised controlled trials (RCTs) comparing dietary interventions with placebo or no treatment in children aged five to 18 years with RAP or an abdominal pain-related, functional gastrointestinal disorder, as defined by the Rome III criteria (Rasquin 2006). DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. We grouped dietary interventions together by category for analysis. We contacted study authors to ask for missing information and clarification, when needed. We assessed the quality of the evidence for each outcome using the GRADE approach. MAIN RESULTS: We included 19 RCTs, reported in 27 papers with a total of 1453 participants. Fifteen of these studies were not included in the previous review. All 19 RCTs had follow-up ranging from one to five months. Participants were aged between four and 18 years from eight different countries and were recruited largely from paediatric gastroenterology clinics. The mean age at recruitment ranged from 6.3 years to 13.1 years. Girls outnumbered boys in most trials. Fourteen trials recruited children with a diagnosis under the broad umbrella of RAP or functional gastrointestinal disorders; five trials specifically recruited only children with irritable bowel syndrome. The studies fell into four categories: trials of probiotic-based interventions (13 studies), trials of fibre-based interventions (four studies), trials of low FODMAP (fermentable oligosaccharides, disaccharides, monosaccharides and polyols) diets (one study), and trials of fructose-restricted diets (one study).We found that children treated with probiotics reported a greater reduction in pain frequency at zero to three months postintervention than those given placebo (standardised mean difference (SMD) -0.55, 95% confidence interval (CI) -0.98 to -0.12; 6 trials; 523 children). There was also a decrease in pain intensity in the intervention group at the same time point (SMD -0.50, 95% CI -0.85 to -0.15; 7 studies; 575 children). However, we judged the evidence for these outcomes to be of low quality using GRADE due to an unclear risk of bias from incomplete outcome data and significant heterogeneity.We found that children treated with probiotics were more likely to experience improvement in pain at zero to three months postintervention than those given placebo (odds ratio (OR) 1.63, 95% CI 1.07 to 2.47; 7 studies; 722 children). The estimated number needed to treat for an additional beneficial outcome (NNTB) was eight, meaning that eight children would need to receive probiotics for one to experience improvement in pain in this timescale. We judged the evidence for this outcome to be of moderate quality due to significant heterogeneity.Children with a symptom profile defined as irritable bowel syndrome treated with probiotics were more likely to experience improvement in pain at zero to three months postintervention than those given placebo (OR 3.01, 95% CI 1.77 to 5.13; 4 studies; 344 children). Children treated with probiotics were more likely to experience improvement in pain at three to six months postintervention compared to those receiving placebo (OR 1.94, 95% CI 1.10 to 3.43; 2 studies; 224 children). We judged the evidence for these two outcomes to be of moderate quality due to small numbers of participants included in the studies.We found that children treated with fibre-based interventions were not more likely to experience an improvement in pain at zero to three months postintervention than children given placebo (OR 1.83, 95% CI 0.92 to 3.65; 2 studies; 136 children). There was also no reduction in pain intensity compared to placebo at the same time point (SMD -1.24, 95% CI -3.41 to 0.94; 2 studies; 135 children). We judged the evidence for these outcomes to be of low quality due to an unclear risk of bias, imprecision, and significant heterogeneity.We found only one study of low FODMAP diets and only one trial of fructose-restricted diets, meaning no pooled analyses were possible.We were unable to perform any meta-analyses for the secondary outcomes of school performance, social or psychological functioning, or quality of daily life, as not enough studies included these outcomes or used comparable measures to assess them.With the exception of one study, all studies reported monitoring children for adverse events; no major adverse events were reported. AUTHORS' CONCLUSIONS: Overall, we found moderate- to low-quality evidence suggesting that probiotics may be effective in improving pain in children with RAP. Clinicians may therefore consider probiotic interventions as part of a holistic management strategy. However, further trials are needed to examine longer-term outcomes and to improve confidence in estimating the size of the effect, as well as to determine the optimal strain and dosage. Future research should also explore the effectiveness of probiotics in children with different symptom profiles, such as those with irritable bowel syndrome.We found only a small number of trials of fibre-based interventions, with overall low-quality evidence for the outcomes. There was therefore no convincing evidence that fibre-based interventions improve pain in children with RAP. Further high-quality RCTs of fibre supplements involving larger numbers of participants are required. Future trials of low FODMAP diets and other dietary interventions are also required to facilitate evidence-based recommendations

    Psychosocial interventions for recurrent abdominal pain in childhood

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    This is the final version. Available from the publisher via the DOI in this record.BACKGROUND: This review supersedes the original Cochrane review first published in 2008 (Huertas-Ceballos 2008).Between 4% and 25% of school-aged children complain of recurrent abdominal pain (RAP) severe enough to interfere with their daily activities. No organic cause for this pain can be found on physical examination or investigation for the majority of such children. Although many children are managed by reassurance and simple measures, a large range of psychosocial interventions involving cognitive and behavioural components have been recommended. OBJECTIVES: To determine the effectiveness of psychosocial interventions for reducing pain in school-aged children with RAP. SEARCH METHODS: In June 2016 we searched CENTRAL, MEDLINE, Embase, eight other databases, and two trials registers. We also searched the references of identified studies and relevant reviews. SELECTION CRITERIA: Randomised controlled trials comparing psychosocial therapies with usual care, active control, or wait-list control for children and adolescents (aged 5 to 18 years) with RAP or an abdominal pain-related functional gastrointestinal disorder defined by the Rome III criteria were eligible for inclusion. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. Five review authors independently selected studies, assessed them for risk of bias, and extracted relevant data. We also assessed the quality of the evidence using the GRADE approach. MAIN RESULTS: This review includes 18 randomised controlled trials (14 new to this version), reported in 26 papers, involving 928 children and adolescents with RAP between the ages of 6 and 18 years. The interventions were classified into four types of psychosocial therapy: cognitive behavioural therapy (CBT), hypnotherapy (including guided imagery), yoga, and written self-disclosure. The studies were carried out in the USA, Australia, Canada, the Netherlands, Germany, and Brazil. The majority of the studies were small and short term; only two studies included more than 100 participants, and only five studies had follow-up assessments beyond six months. Small sample sizes and the degree of assessed risk of performance and detection bias in many studies led to the overall quality of the evidence being rated as low to very low for all outcomes.For CBT compared to control, we found evidence of treatment success postintervention (odds ratio (OR) 5.67, 95% confidence interval (CI) 1.18 to 27.32; Z = 2.16; P = 0.03; 4 studies; 175 children; very low-quality evidence), but no evidence of treatment success at medium-term follow-up (OR 3.08, 95% CI 0.93 to 10.16; Z = 1.85; P = 0.06; 3 studies; 139 children; low-quality evidence) or long-term follow-up (OR 1.29, 95% CI 0.50 to 3.33; Z = 0.53; P = 0.60; 2 studies; 120 children; low-quality evidence). We found no evidence of effects of intervention on pain intensity scores measured postintervention (standardised mean difference (SMD) -0.33, 95% CI -0.74 to 0.08; 7 studies; 405 children; low-quality evidence), or at medium-term follow-up (SMD -0.32, 95% CI -0.85 to 0.20; 4 studies; 301 children; low-quality evidence).For hypnotherapy (including studies of guided imagery) compared to control, we found evidence of greater treatment success postintervention (OR 6.78, 95% CI 2.41 to 19.07; Z = 3.63; P = 0.0003; 4 studies; 146 children; low-quality evidence) as well as reductions in pain intensity (SMD -1.01, 95% CI -1.41 to -0.61; Z = 4.97; P < 0.00001; 4 studies; 146 children; low-quality evidence) and pain frequency (SMD -1.28, 95% CI -1.84 to -0.72; Z = 4.48; P < 0.00001; 4 studies; 146 children; low-quality evidence). The only study of long-term effect reported continued benefit of hypnotherapy compared to usual care after five years, with 68% reporting treatment success compared to 20% of controls (P = 0.005).For yoga therapy compared to control, we found no evidence of effectiveness on pain intensity reduction postintervention (SMD -0.31, 95% CI -0.67 to 0.05; Z = 1.69; P = 0.09; 3 studies; 122 children; low-quality evidence).The single study of written self-disclosure therapy reported no benefit for pain.There was no evidence of effect from the pooled analyses for any type of intervention on the secondary outcomes of school performance, social or psychological functioning, and quality of daily life.There were no adverse effects for any of the interventions reported. AUTHORS' CONCLUSIONS: The data from trials to date provide some evidence for beneficial effects of CBT and hypnotherapy in reducing pain in the short term in children and adolescents presenting with RAP. There was no evidence for the effectiveness of yoga therapy or written self-disclosure therapy. There were insufficient data to explore effects of treatment by RAP subtype.Higher-quality, longer-duration trials are needed to fully investigate the effectiveness of psychosocial interventions. Identifying the active components of the interventions and establishing whether benefits are sustained in the long term are areas of priority. Future research studies would benefit from employing active control groups to help minimise potential bias from wait-list control designs and to help account for therapist and intervention time.The work of the evidence synthesis team is funded by the National Institute for Health Research Collaboration for Leadership in Applied Health Research and Care South West Peninsula (PenCLAHRC). However, the funder had no role in the review itself
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