Showing papers by "Michael P. Jones published in 2007"

Carbon mitigation by the energy crop, Miscanthus

Abstract: Clifton-Brown, J. C., Breuer, J., Jones, M. B. (2007). Carbon mitigation by the energy crop, Miscanthus. Global Change Biology. 13 (11), 2296-2307 Sponsorship: EU JOUB-0069 / AIR-CT92-0294 RAE2008

Energy crops in Ireland: Quantifying the potential life-cycle greenhouse gas reductions of energy-crop electricity

Abstract: This study uses life-cycle assessment (LCA) to compare greenhouse gas (GHG) emissions from dominant agricultural land uses, and peat and coal electricity generation, with fuel-chains for Miscanthus and short-rotation-coppice willow (SRCW) electricity. A simple scenario was used as an example, where 30% of peat and 10% of coal electricity generation was substituted with co-fired Miscanthus and SRCW, respectively. Miscanthus and SRCW cultivation were assumed to replace sugar-beet, dairy, beef-cattle and sheep systems. GHG emissions of 1938 and 1346 kg CO 2 eq. ha −1 a −1 for Miscanthus and SRCW cultivation compared with between 3494 CO 2 eq. ha −1 a −1 for sugar-beet cultivation and 12,068 CO 2 eq. ha −1 a −1 for dairy systems. Miscanthus and SRCW fuel chains emitted 0.131 and 0.132 kg CO 2 eq. kWh −1 electricity exported, respectively, compared with 1.150 and 0.990 kg CO 2 eq. kWh −1 electricity exported for peat and coal fuel chains. 1.48 Mt CO 2 eq. a −1 was saved from electricity production, and 0.42 Mt CO 2 eq. a −1 was saved from displaced agriculture and soil C-sequestration. The total reduction of 1.9 Mt CO 2 eq. a −1 represents 2.8% of Ireland's 2004 GHG emissions, but was calculated to require just 1.7% of agricultural land area and displace just 1.2% of the dairy herd (based on conservative Miscanthus and SRCW combustible-yield estimates of 11.7 and 8.81 t ha −1 a −1 dry matter, respectively). A 50% increase in cultivation emissions would still result in electricity being produced with an emission burden over 80% lower than peat and coal electricity. Lower yield assumptions had little impact on total GHG reductions for the scenario, but required substantially greater areas of land. It was concluded that energy-crop utilisation would be an efficient GHG reduction strategy for Ireland.

Influence of genetics on irritable bowel syndrome, gastro-oesophageal reflux and dyspepsia: a twin study.

Abstract: Summary Background A genetic contribution has been proposed for irritable bowel syndrome (IBS) and gastro-oesophageal reflux disease (GERD), but is controversial. No twin data exist for dyspepsia. Aim To determine the relative contribution of genetic factors in GERD, dyspepsia (upper abdominal pain) and IBS. Methods A total of 986 twin pairs (from initial mail-out response 51%). Both members completed validated symptom and psychological questionnaires; 481 monozygotic pairs [mean (s.d.) age 53 ± 5.8 years] and 505 dizygotic pairs (mean age 54 ± 5.6 years). Results Prevalence of IBS, dyspepsia and GERD was 12%, 10% and 20%, respectively. Polychoric correlation for monozygotic twins for IBS (0.47) and GERD (0.44) were both substantially larger than those for dizygotic twins (0.17 and −0.37, respectively). Polychoric correlation was slightly lower in monozygotic than dizygotic twins for dyspepsia. Genetic modelling confirmed the independent additive genetic effects in GERD and IBS but not dyspepsia. Estimates of genetic variance were 22% for IBS, 13% for GERD and 0% for dyspepsia, but adjusting for anxiety and depression removed the statistical significance for IBS and GERD. Conclusions There is a genetic contribution to GERD and IBS but not dyspepsia; this may be mediated by the hereditability of anxiety and depression.

Carbon and water cycles in tropical papyrus wetlands

Abstract: Highly productive papyrus (Cyperus papyrus L.) wetlands dominate many permanently flooded areas of tropical East Africa; however, the cycling of carbon and water within these ecosystems is poorly understood. The objective of this study was to utilise Eddy Covariance (EC) techniques to measure the fluxes of carbon dioxide and water vapour between papyrus vegetation and the atmosphere in a wetland located near Jinja, Uganda on the Northern shore of Lake Victoria. Peak, midday rates of photosynthetic CO2 net assimilation were approximately 40 μmol CO2 m−2 s−1, while night time losses through respiration ranged between 10 and 20 μmol CO2 m−2 s−1. Numerical integration of the flux data suggests that papyrus wetlands have the potential to sequester approximately 0.48 kg C m−2 y−1. The average daily water vapour flux from the papyrus vegetation through canopy evapotranspiration was approximately 4.75 kg H2O m−2 d−1, which is approximately 25% higher than water loss through evaporation from open water.

The frequency of constipation in children with nocturnal enuresis: a comparison with parental reporting.

Abstract: Aims: To identify the prevalence of constipation in children with nocturnal enuresis presenting to a tertiary paediatric outpatient service and to assess parental and clinician recognition of constipation. Methods: A prospective cross-sectional study of children with nocturnal enuresis at presentation to a continence service. Data relating to the child’s bowel habits, pattern of enuresis and other history items were obtained from parental questionnaires and paediatrician assessments. Presence and severity of constipation was assessed independently by parents and clinicians. Kappa was used to compare agreement between parental reporting and clinician assessment of constipation. Results: Of the 277 participants aged 4.8–17.5 years (median 8.6 years), 36.1% (n = 95) were identified as constipated by the clinician-based scoring method (‘Constipation Score’) compared with 14.1% from parental reporting (Kappa = 0.155, P = 0.003). Despite the poor overall recognition of constipation by parents, parental and clinician assessment of frequency of bowel motions (Kappa = 0.804) and soiling (Kappa = 0.384) were similar. Major factors influencing parental reporting of constipation were frequency of bowel motions and soiling with less emphasis on straining and stool consistency. Conclusions: Prevalence of constipation was high among children with nocturnal enuresis as assessed by clinicians despite poor identification by parents. This may limit optimal diagnosis and management.

Estimating the greenhouse gas fluxes of European grasslands with a process-based model: 1. Model evaluation from in situ measurements

Abstract: [1] We improved a process-oriented biogeochemical model of carbon and nitrogen cycling in grasslands and tested it against in situ measurements of biomass and CO2 and CH4 fluxes at five European grassland sites. The new version of the model (PASIM) calculates the growth and senescence of aboveground vegetation biomass accounting for sporadic removals when the grassland is cut and for continuous removals when it is grazed. Limitations induced by high leaf area index (LAI), soil water deficits and aging of leaves are also included. We added to this a simple empirical formulation to account for the detrimental impact on vegetation of trampling and excreta by grazing animals. Finally, a more realistic methane emission module than is currently used was introduced on the basis of the quality of the animals' diet. Evaluation of this improved version of PASIM is performed at (1) Laqueuille, France, on grassland continuously grazed by cattle with two plots of intensive and extensive grazing intensities, (2) Oensingen, Switzerland, on cut grassland with two fertilized and nonfertilized plots, and (3) Carlow, Ireland, on grassland that is both cut and grazed by cattle during the growing season. In addition, we compared the modeled animal CH4 emissions with in situ measurements on cattle for two grazing intensities at the grazed grassland site of Laqueuille. Altogether, when all improvements to the PASIM model are included, we found that the new parameterizations resulted into a better fit to the observed seasonal cycle of biomass and of measured CO2 and CH4 fluxes. However, the large uncertainties in measurements of biomass and LAI make simulation of biomass dynamics difficult to make. Also simulations for cut grassland are better than for grazed swards. This work paves the way for simulating greenhouse gas fluxes over grasslands in a spatially explicit manner, in order to quantify and understand the past, present and future role of grasslands in the greenhouse gas budget of the European continent.

Reducing door to antibiotic time in community-acquired pneumonia: controlled before and after evaluation and cost-effectiveness analysis

Abstract: Background: Practice guidelines suggest that all patients hospitalised with community-acquired pneumonia (CAP) should receive antibiotics within 4 h of admission. An audit at our hospital during 1999–2000 showed that this target was achieved in less than two thirds of patients with severe CAP. Methods: An experienced multidisciplinary steering group designed a management pathway to improve the early delivery of appropriate antibiotics to patients with CAP. This was implemented using a multifaceted strategy. The effect of implementation was evaluated using a controlled before-and-after study design over two winter seasons (November–April 2001–2 and 2002–3). Cost-effectiveness analyses were performed from the hospital’s perspective. Results: The proportion of patients receiving appropriate antibiotics within 4 h of admission to hospital increased from 33% to 56% at the intervention site, and from 32% to 36% at the control site (absolute change adjusted for differences in severity of illness 17%, p = 0.035). The cost per additional patient receiving appropriate antibiotics within 4 h was £132 with no post-implementation evaluation, and £456 for a limited post-implementation evaluation. Simple modelling from the results of a large observational study suggests that the cost per death prevented could be £3003 with no post-implementation evaluation, or £16 632 with a limited post-implementation evaluation. Conclusions: The intervention markedly improved door-to-antibiotic time, albeit at considerable cost. It might still be a cost-effective strategy, however, to reduce mortality in CAP. Uncertainty about the cost effectiveness of such interventions is likely to be resolved only by a well-designed, cluster randomised trial.

Small intestinal motility.

Abstract: Purpose of reviewTo review recently published studies presenting novel and relevant information on small intestinal motility.Recent findingsThe reviewed studies covered a variety of topics with several themes emerging. Our understanding of the influence of systemic disorders, intestinal and extraint

European-wide GIS-based modelling system for quantifying the feedstock from Miscanthus and the potential contribution to renewable energy targets

Abstract: Reliable estimates of feedstock resources are a prerequisite to the establishment of a biomass based-industry for energy and non food products. Field trials in the European Union (EU) show that Miscanthus spp. can produce high yields. Here we use a model (MISCANMOD) coupled with a GIS environment to estimate the contribution that Miscanthus could make to projected national electricity consumption. We describe the integration of different data sets, transformation procedures, and spatial analyses using GIS to produce energy statistics for the EU-25. Overall, Miscanthus grown on the 10% of arable land which is currently in set-aside could generate 282 TWh yr−1 electricity. This would meet 39% of the EU-25 target of 723 TWh yr−1 of electricity from renewable energy sources (RES) by 2010. As RES targets rise, land available for energy crops is also expected to increase. We consider three additional scenarios where Miscanthus could be grown on 10%, 20% and 35% of all agricultural land and we estimate it could generate respectively 345, 691 and 1209 TWh yr−1 of electrical energy. At a national scale France, Poland and Germany have the highest potentials for Miscanthus production based on agricultural land area (respectively 83, 52, 49 TWh yr−1 when 10% agricultural land is used). Finally, we reduced the scale to the EU NUTS2 (Nomenclature of Territorial Units for Statistics) regions to examine regional generation capacities. Key regions have been identified where national RES targets are exceeded. These regions could become net exporters of renewable energy.

Impact of anal incontinence on psychosocial function and health-related quality of life

Abstract: The relationship among the frequency of anal incontinence (AI), psychosocial factors, and health-related quality of life (HRQOL) was evaluated. Consecutive patients (n=280) completed a bowel symptom questionnaire, the Symptom Checklist 90—Revised (SCL 90-R), and an assessment of HRQOL. Group 1 had no incontinence, Group 2 had AI less than once per week, and Group 3 experienced AI more than once per week. Multivariate analyses were used to evaluate the relationship among symptoms, the SCL-90-R subscales, and HRQOL. Group 3 reported more frequent stools than the other groups. Significant psychological distress was present in both incontinent groups compared to Group 1 (P=0.002). A reduction in overall HRQOL was also seen in the incontinent groups. Depression was inversely correlated with QOL-Satisfaction and QOL-Ratings and positively correlated with QOL-Interference. AI was associated with impaired psychosocial function and decreased HRQOL. The frequency of AI was associated with increased HRQOL-Interference, but minimally with the degree of psychosocial impairment.

Meta-analysis of randomised controlled trials comparing latanoprost with brimonidine in the treatment of open-angle glaucoma, ocular hypertension or normal-tension glaucoma

Abstract: Aim: To compare the efficacy and tolerability of latanoprost versus brimonidine in the treatment of open-angle glaucoma, ocular hypertension or normal-tension glaucoma. Method: Systematic review of randomised controlled trials comparing latanoprost and brimondine, identified by searches including Medline, Embase and Cochrane Controlled Trials Register. Two reviewers independently assessed trials for eligibility and quality and extracted data. Data were synthesised (random effects model) and expressed as the absolute mean intraocular pressure (IOP) reduction difference from baseline to end point for efficacy and relative risk for adverse events. Subgroup analysis and regression were used to explore heterogeneity according to patient characteristics, trial design and quality. Results: 15 publications reporting on 14 trials (1784 participants) were included for meta-analysis. IOP reduction favoured latanoprost (weighted mean difference (WMD) = 1.10 mm Hg (95% confidence interval (CI) 0.57 to 1.63)). Significant heterogeneity was present (χ213 = 38.29, p = 0.001, I2 = 66.0%). Subgroup analysis showed greater WMD for studies where data were analysed from end points >6 months duration, cross-over design, open-angle glaucoma or ocular hypertension and monotherapy. Multiple regression showed no significant association of WMD with trial duration (t9 = 1.92, p = 0.09), trial design (t9 = 1.79, p = 0.11), trial quality (t9 = −0.46, p = 0.66), or monotherapy or adjunctive therapy (t9 = −2.14, p = 0.06). Fatigue was less commonly associated with latanoprost (RR = 0.27, 95% CI 0.08 to 0.88). Publication bias was not evident on visual inspection of a funnel plot. Conclusion: Latanoprost is more effective than brimonidine as monotherapy in lowering IOP. Brimonidine is associated with a higher rate of fatigue.

Vanishing Point: Spatial Composition and the Virtual Camera:

Abstract: This article examines new aesthetic modes of cinematic space. Specifically, the author examines the `virtual camera' (in practical and technical terms derived from animation born of computer-generated 3D graphics, layer-based motion graphics and most distinctly from computer and video gaming) as a construct for spatial composition, scenic depiction and viewer immersion that possesses distinct and unique qualities of engagement. The article argues that under the influence of the virtual camera, both a hybridized and re-mediated means of moving-image acquisition, cinema aesthetics are shifting; from the duopoly of composition in the frame and the staging for the camera, to a new mode entailing a composition of space and a staging of the camera. This article also examines the virtual camera in the framework of three key, oppositional, cinematic animation and narrative concepts — diegetic positioning; mediated and unmediated engagement; and diegesis and mimesis in narrative and perspective condition. This exa...