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Search Results: 1 - 10 of 24979 matches for " Paul Johnston "
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Transforming Government's Policy-making Processes
Paul Johnston
eJournal of eDemocracy & Open Government , 2010,
Abstract: We have seen a lot of very welcome progress in terms of making it easier for citizens to input their views into government policy-making processes. However, governments and citizens are now in a similar situation – after a burst of initial enthusiasm, they are not sure what to do next. Governments have struggled to get the mass participation they would like and where significant participation has occurred, have had difficulty integrating it effectively into existing decision-making processes. Citizens have been unsure what to make of this new apparent openness and where they have engaged, have found it hard to know what difference their input made. The solution is to focus on using technology to make existing policy processes more transparent and more participative rather than creating separate e-participation initiatives. The challenge for governments is to open up the whole of the policy process and be prepared to flag up very clearly and explicitly the difference citizen input made. The challenge for e-democracy advocates is to convince policymakers that their ideas can improve the existing policy process rather than simply generating more inputs into it.
Host and Symbiont Jointly Control Gut Microbiota during Complete Metamorphosis
Paul R. Johnston,Jens Rolff
PLOS Pathogens , 2015, DOI: 10.1371/journal.ppat.1005246
Abstract: Holometabolous insects undergo a radical anatomical re-organisation during metamorphosis. This poses a developmental challenge: the host must replace the larval gut but at the same time retain symbiotic gut microbes and avoid infection by opportunistic pathogens. By manipulating host immunity and bacterial competitive ability, we study how the host Galleria mellonella and the symbiotic bacterium Enterococcus mundtii interact to manage the composition of the microbiota during metamorphosis. Disenabling one or both symbiotic partners alters the composition of the gut microbiota, which incurs fitness costs: adult hosts with a gut microbiota dominated by pathogens such as Serratia and Staphylococcus die early. Our results reveal an interaction that guarantees the safe passage of the symbiont through metamorphosis and benefits the resulting adult host. Host-symbiont “conspiracies” as described here are almost certainly widespread in holometobolous insects including many disease vectors.
Tumor Volume Associated with Recurrence in Prostate Cancer Patients with Seminal Vesicle Invasion  [PDF]
Paul H. Johnston, Timothy A. Masterson, Liang Cheng, Michael O. Koch
Open Journal of Urology (OJU) , 2012, DOI: 10.4236/oju.2012.223033
Abstract: Objectives: To examine predictors of progression-free survival in men with seminal vesicle invasion (SVI) following radical prostatectomy (RP) for clinically localized prostate cancer. Methods and Materials: Between 1999 and 2009, 1383 men underwent RP at Indiana University. Among them, 115 men were identified with SVI. Disease progression was defined by a rise in PSA ≥ 0.2 ng/ml, receipt of salvage therapy, progression to metastatic disease, or death. After excluding 13 patients for receiving adjuvant therapy, 102 were stratified according to surgical margin (SM) and lymph node (LN) status for Kaplan-Meier analysis of disease progression. Cox proportional hazards analyses of biochemical progression-free survival were undertaken with respect to margin status, pre-operative prostate specific antigen (PSA), tumor volume, age, and post-operative Gleason sum. Stem and leaf plot was undertaken for tumor volume by biochemical PFS. Results: Mean age was 61 years, median Gleason sum was 7, mean tumor volume was 9.7 ml, and mean pre-operative PSA was 13.6 ng/ml. Mean time to disease progression was 17 months. Mean follow-up was 37 months. Kaplan-Meier analysis revealed statistically insignificant differences in progression-free survival stratified by SM and LN status (p = 0.12). Cox univariate analyses revealed tumor volume to be a statistically significant predictor of progression free survival (p = 0.02). Stem and Leaf plot revealed tumor volume to be statistically significantly larger in patients who experienced biochemical recurrence, compared to those who did not. Conclusion: Tumor volume was associated progression-free survival in this cohort of SVI patients, while pathologic Gleason sum, PSA, margin and nodal status were not.
The Redox System in C. elegans, a Phylogenetic Approach
Andrew D. Johnston,Paul R. Ebert
Journal of Toxicology , 2012, DOI: 10.1155/2012/546915
Abstract: Oxidative stress is a toxic state caused by an imbalance between the production and elimination of reactive oxygen species (ROS). ROS cause oxidative damage to cellular components such as proteins, lipids, and nucleic acids. While the role of ROS in cellular damage is frequently all that is noted, ROS are also important in redox signalling. The “Redox Hypothesis" has been proposed to emphasize a dual role of ROS. This hypothesis suggests that the primary effect of changes to the redox state is modified cellular signalling rather than simply oxidative damage. In extreme cases, alteration of redox signalling can contribute to the toxicity of ROS, as well as to ageing and age-related diseases. The nematode species Caenorhabditis elegans provides an excellent model for the study of oxidative stress and redox signalling in animals. We use protein sequences from central redox systems in Homo sapiens, Drosophila melanogaster, and Saccharomyces cerevisiae to query Genbank for homologous proteins in C. elegans. We then use maximum likelihood phylogenetic analysis to compare protein families between C. elegans and the other organisms to facilitate future research into the genetics of redox biology. 1. Introduction Molecular oxygen is necessary for the survival of most complex multicellular organisms. The necessity of oxygen comes from its role in aerobic respiration, a process of extracting energy from food that is approximately 19 times more efficient than its anaerobic counterpart. In eukaryotes, aerobic respiration is carried out in the mitochondria (descendant of an aerobically respiring bacterium) by a series of electron transfer reactions that are coupled to the generation of a proton gradient. This proton gradient is used to generate the cellular fuel adenosine triphosphate (ATP). The residual energy of the spent electrons is consumed in the reduction of molecular oxygen (O2) to water (H2O). Aerobic respiration cannot occur without this last step, but the reliance on oxygen as the final electron acceptor poses a continual threat of oxidative damage to aerobically respiring organisms. The threat posed by oxygen comes largely from its conversion to the free radical superoxide ( O 2 ? ? ) rather than water [1]. Superoxide is a highly reactive short-lived ROS. Detoxification of superoxide and other ROS is performed by antioxidants, which convert ROS to less reactive molecules. The antioxidant enzyme superoxide dismutase (SOD) converts superoxide to water and hydrogen peroxide (H2O2), which is another ROS and a potent oxidising agent (see Figure 1) [2]. Under
Exploring the relationships between International Classification of Functioning, Disability and Health (ICF) constructs of Impairment, Activity Limitation and Participation Restriction in people with osteoarthritis prior to joint replacement
Beth Pollard, Marie Johnston, Paul Dieppe
BMC Musculoskeletal Disorders , 2011, DOI: 10.1186/1471-2474-12-97
Abstract: A geographical cohort of 413 patients with osteoarthritis about to undergo hip and knee joint replacement completed the Aberdeen measures of Impairment, Activity Limitation and Participation Restriction (Ab-IAP). Confirmatory factor analysis was used to test the three factor (I, A, P) measurement model. Structural equation modelling was used to explore the I, A and P pathways in the ICF model.There was support from confirmatory factor analysis for the three factor I, A, P measurement model. The structural equation model had good fit [S-B Chi-square = 439.45, df = 149, CFI robust = 0.91, RMSEA robust = 0.07] and indicated significant pathways between I and A (standardised coefficient = 0.76 p < 0.0001) and between A and P (standardised coefficient = 0.75 p < 0.0001). However, the path between I and P was not significant (standardised coefficient = 0.01).The significant pathways suggest that treatments and interventions aimed at reducing impairment, such as joint replacement, may only affect P indirectly, through A, however, longitudinal data would be needed to establish this.Osteoarthritis (OA) in the lower limbs (hips and knees) is one of the commonest cause of physical disability in older people [1]. Many treatments are available, some of which target an impairment, such as pain, or restrictions of joint movement, and some on activities limitations, such as reduced walking ability or difficulties with stair climbing (e.g.[2-5]). However, an important issue, for people with OA is to improve their participation in society which has been restricted by the impairments and activities limitations [6-8]. It is therefore important to know the relationships between impairments, activities limitations and restricted participation in this patient group.The leading model of disability is the International Classification of Functioning, Disability and Health (ICF) [9]. The ICF proposes three main constructs, impairment (I), activity limitation (A) and participation restriction
The Fate of Aflatoxin in Corn Fermentation  [PDF]
C. Ian Johnston, Rebecca Singleterry, Cedric Reid, Darrell Sparks, Ashli Brown, Brian Baldwin, Stephanie Hill Ward, W. Paul Williams
Natural Resources (NR) , 2012, DOI: 10.4236/nr.2012.33017
Abstract: A lab-scale ethanol fermentation was investigated to determine where aflatoxin concentrated during each phase of production. Four corn samples with high levels of aflatoxin (ranging from 7750 – 17,208 parts per billion) and their replicates were compared with a replicated negative control. Fractions were taken from the fermented mash, distilled ethanol, stillage, and dried corn solids (DCS). These fractions were analyzed using two different immunoassay methods and liquid chromatography tandem mass spectrometry (LC-MS/MS). Results indicated no aflatoxin was found in the distilled ethanol. Some aflatoxin (13%) was detected in the stillage, but most of the toxin was recovered in the DCSs ranging from 31% to 58%. A second series of experiments were conducted to investigate the effect of binders on dried distillers grains (DDGs). A brewers dried yeast anti-caking binder that contains glucomannon (MTB-100?), was mixed with contaminated DDGs. Addition of the binder showed a significant reduction in aflatoxin levels in comparison to a positive control. Aflatoxin binding at 2% binder w/w reached 72.5% and showed a minimal binding percentage increase of 80% at 6% binder w/w. Testing was also conducted to determine if environmental variables such as pH and temperature had any effect on the binding capabilities. Temperature near 0?C resulted in binding at 19.7% at a pH range of 6 to 8. Additionally, at a temperature of 40?C resulted in binding of 36%, 47%, and 45% at pHs 6, 7, and 8, respectively. These findings suggest that the addition of sorbents may be an effective way of salvaging contaminated DDGs.
Islanding Operation of Electrical Systems in Buildings  [PDF]
David Johnston
Energy and Power Engineering (EPE) , 2013, DOI: 10.4236/epe.2013.54B038
Abstract: A control system was developed, which allows on-site generators within a building to operate in islanding mode, in the event of loss of grid supply. The on-site generation included a photovoltaic array and a back-up induction generator. Regulation include avoidance of sudden voltage and frequency changes at the transition to islanding mode, maintaining voltage and frequency within limits during islanding, and phase matching when the grid supply is re-established. Possible modes of operation during islanding were photovoltaic array alone, generator alone, or both sources operating in parallel. Control methods were considered for each of these, and the resulting voltage and frequency regulation was anal sized. The results show that voltage and frequency could be kept within limits, except during the transitions to and from islanding. At these times, the transients were minimised.
On-Line Independent Tap-Changing of Each Feeder Supplied by a Low Voltage Distribution Transformer  [PDF]
David Johnston
Journal of Power and Energy Engineering (JPEE) , 2014, DOI: 10.4236/jpee.2014.24052
Abstract: An on-line tap-changing circuit was developed for use with low voltage transformers (10 kV/380 V, or equivalent), in which the tap positions could be set independently for each low voltage feeder. This allows for possible variation in loads and distributed generation between different feeders fed from a given transformer, allowing the line voltages to be kept within limits on all feeders. A combination of computer simulation and practical experiments was used. A model constructed in Excel gave preliminary results, which was used to specify a more detailed model in Matlab? Simulink. A small-scale 220/380 V distribution network was constructed, with currents limited to 5 A per phase. Finally, a rotary switch was constructed, suitable for currents up to 500 A, which would be required for a full-scale low voltage distribution network. The results showed that the voltage
could be kept within limits, even with a large difference in load and distributed generation from one feeder to another.
What is known about the patient's experience of medical tourism? A scoping review
Valorie A Crooks, Paul Kingsbury, Jeremy Snyder, Rory Johnston
BMC Health Services Research , 2010, DOI: 10.1186/1472-6963-10-266
Abstract: A comprehensive scoping review of published academic articles, media sources, and grey literature reports was performed to answer the question: what is known about the patient's experience of medical tourism? The review was accomplished in three steps: (1) identifying the question and relevant literature; (2) selecting the literature; (3) charting, collating, and summarizing the information. Overall themes were identified from this process.291 sources were identified for review from the databases searched, the majority of which were media pieces (n = 176). A further 57 sources were included for review after hand searching reference lists. Of the 348 sources that were gathered, 216 were ultimately included in this scoping review. Only a small minority of sources reported on empirical studies that involved the collection of primary data (n = 5). The four themes identified via the review were: (1) decision-making (e.g., push and pull factors that operate to shape patients' decisions); (2) motivations (e.g., procedure-, cost-, and travel-based factors motivating patients to seek care abroad); (3) risks (e.g., health and travel risks); and (4) first-hand accounts (e.g., patients' experiential accounts of having gone abroad for medical care). These themes represent the most discussed issues about the patient's experience of medical tourism in the English-language academic, media, and grey literatures.This review demonstrates the need for additional research on numerous issues, including: (1) understanding how multiple information sources are consulted and evaluated by patients before deciding upon medical tourism; (2) examining how patients understand the risks of care abroad; (3) gathering patients' prospective and retrospective accounts; and (4) the push and pull factors, as well as the motives of patients to participate in medical tourism. The findings from this scoping review and the knowledge gaps it uncovered also demonstrate that there is great potential for new co
Measuring the ICF components of impairment, activity limitation and participation restriction: an item analysis using classical test theory and item response theory
Beth Pollard, Diane Dixon, Paul Dieppe, Marie Johnston
Health and Quality of Life Outcomes , 2009, DOI: 10.1186/1477-7525-7-41
Abstract: A geographical cohort of patients about to undergo lower limb joint replacement was invited to participate. Five hundred and twenty four patients completed ICF items that had been previously identified as measuring only a single ICF construct in patients with osteoarthritis. There were 13 I, 26 A and 20 P items. The SF-36 was used to explore the construct validity of the resultant I, A and P measures. The CTT and IRT analyses were run separately to identify items for inclusion or exclusion in the measurement of each construct. The results from both analyses were compared and contrasted.Overall, the item analysis resulted in the removal of 4 I items, 9 A items and 11 P items. CTT and IRT identified the same 14 items for removal, with CTT additionally excluding 3 items, and IRT a further 7 items. In a preliminary exploration of reliability and validity, the new measures appeared acceptable.New measures were developed that reflect the ICF components of Impairment, Activity Limitation and Participation Restriction for patients with advanced arthritis. The resulting Aberdeen IAP measures (Ab-IAP) comprising I (Ab-I, 9 items), A (Ab-A, 17 items), and P (Ab-P, 9 items) met the criteria of conventional psychometric (CTT) analyses and the additional criteria (information and discrimination) of IRT. The use of both methods was more informative than the use of only one of these methods. Thus combining CTT and IRT appears to be a valuable tool in the development of measures.The aim of this paper was to develop measures that reflect the health components identified by the International Classification of Functioning, Disability and Health (ICF) for use with people having joint replacement surgery. Item analysis was carried out using both Classical Test Theory (CTT) and Item Response Theory (IRT) on a group of candidate Impairment (I), Activity Limitation (A) and Participation Restriction (P) items. The items had been previously judged to be measuring one, and only one, of the thr
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