753 research outputs found

    The effect of precipitation and application rate on dicyandiamide persistence and efficiency in two Irish grassland soils

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    peer-reviewedThe nitrification inhibitor dicyandiamide (DCD) has had variable success in reducing nitrate (NO3-) leaching and nitrous oxide (N2O) emissions from soils receiving nitrogen (N) fertilisers. Factors such as soil type, temperature and moisture have been linked to the variable efficacy of DCD. Since DCD is water soluble it can be leached from the rooting zone where it is intended to inhibit nitrification. Intact soil columns (15 cm diameter by 35 cm long) were taken from luvic gleysol and haplic cambisol grassland sites and placed in growth chambers. DCD was applied at 15 or 30 kg DCD ha-1, with high or low precipitation. Leaching of DCD, mineral N and the residual soil DCD concentrations were determined over eight weeks High precipitation increased DCD in leachate and decreased recovery in soil. A soil x DCD rate interaction was detected for the DCD unaccounted (proxy for degraded DCD). In the cambisol degradation of DCD was high (circa 81%) and unaffected by DCD rate. In contrast DCD degradation in the gleysol was lower and differentially affected by rate, 67 and 46% for the 15 and 30 kg ha-1 treatments, respectively. Differences DCD degradation rates between soils may be related to differences in organic matter content and associated microbiological activity. Variable degradation rates of DCD in soil, unrelated to temperature or moisture, may contribute to varying DCD efficacy. Soil properties should be considered when tailoring DCD strategies for improving nitrogen use efficiency and crop yields, through the reduction of reactive nitrogen loss.This research was financially supported under the National Development Plan, through the Research Stimulus Fund, administered by the Department of Agriculture, Food and the Marine under grants 07519 and 07545

    Improving and disaggregating N2O emission factors for ruminant excreta on temperate pasture soils

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    pre-printCattle excreta deposited on grazed grasslands are a major source of the greenhouse gas (GHG) nitrous oxide (N2O). Currently, many countries use the IPCC default emission factor (EF) of 2% to estimate excreta-derived N2O emissions. However, emissions can vary greatly depending on the type of excreta (dung or urine), soil type and timing of application. Therefore three experiments were conducted to quantify excreta-derived N2O emissions and their associated EFs, and to assess the effect of soil type, season of application and type of excreta on the magnitude of losses. Cattle dung, urine and artificial urine treatments were applied in spring, summer and autumn to three temperate grassland sites with varying soil and weather conditions. Nitrous oxide emissions were measured from the three experiments over 12 months to generate annual N2O emission factors. The EFs from urine treated soil was greater (0.30–4.81% for real urine and 0.13–3.82% for synthetic urine) when compared with dung (− 0.02–1.48%) treatments. Nitrous oxide emissions were driven by environmental conditions and could be predicted by rainfall and temperature before, and soil moisture deficit after application; highlighting the potential for a decision support tool to reduce N2O emissions by modifying grazing management based on these parameters. Emission factors varied seasonally with the highest EFs in autumn and were also dependent on soil type, with the lowest EFs observed from well-drained and the highest from imperfectly drained soil. The EFs averaged 0.31 and 1.18% for cattle dung and urine, respectively, both of which were considerably lower than the IPCC default value of 2%. These results support both lowering and disaggregating EFs by excreta type.This research was financially supported under the National Development Plan, through the Research Stimulus Fund, administered by the Department of Agriculture, Food and the Marine (Grant numbers RSF10/RD/SC/716 and 11S138)

    Pre-procedural planning of transcatheter mitral valve replacement in mitral stenosis with multi-detector tomography-derived 3D modeling and printing: A case report

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    Background: Transcatheter mitral valve replacement (TMVR) may be a valuable treatment option for mitral annular calcification and severe mitral stenosis (MS) in patients at high operative risk. Pre-procedural virtual and printed simulations may aid in procedure planning, device sizing, and mitigate complications such as valve embolization or left ventricular outflow tract (LVOT) obstruction. Case summary: We describe a case of TMVR in which multi-detector computed tomography (MDCT) derived, three-dimensional virtual planning and a 3D-printed model of the patients' left heart provided enhanced understanding of an individual patient's unique anatomy to determine feasibility, device sizing, and risk stratification. This resulted in deployment of an adequately sized valve. Post-TMVR LVOT obstruction was treated with LVOT balloon dilatation and percutaneous transluminal septal myocardial ablation. Discussion: Advanced MDCT-derived planning techniques introduce consistent 3D modeling and printing to enhance understanding of intracardiac anatomical relationships and test device implantation. Still, static measurements do not feature haemodynamic factors, tissue, or device characteristics and do not predict device host interaction. Transcatheter mitral valve replacement is feasible in MS when adequately pre-procedurally planned. Multi-detector computed tomography-derived, 3D, virtual and printed models contribute to adequate planning in terms of determining patient eligibility, procedure feasibility, and device sizing. However, static 3D modeling cannot completely eliminate the risk of peri-procedural complications

    The interactive effects of various nitrogen fertiliser formulations applied to urine patches on nitrous oxide emissions in grassland

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    peer-reviewedPasture-based livestock agriculture is a major source of greenhouse gas (GHG) nitrous oxide (N2O). Although a body of research is available on the effect of urine patch N or fertiliser N on N2O emissions, limited data is available on the effect of fertiliser N applied to patches of urinary N, which can cover up to a fifth of the yearly grazed area. This study investigated whether the sum of N2O emissions from urine and a range of N fertilisers, calcium ammonium nitrate (CAN) or urea ± urease inhibitor ± nitrification inhibitor, applied alone (disaggregated and re-aggregated) approximated the N2O emission of urine and fertiliser N applied together (aggregated). Application of fertiliser to urine patches did not significantly increase either the cumulative yearly N2O emissions or the N2O emission factor in comparison to urine and fertiliser applied separately with the emissions re-aggregated. However, there was a consistent trend for approximately 20% underestimation of N2O loss generated from fertiliser and urine applied separately when compared to figures generated when urine and fertiliser were applied together. N2O emission factors from fertilisers were 0.02%, 0.06%, 0.17% and 0.25% from urea ± dicyandiamide (DCD), urea + N-(n-butyl) thiophosphoric triamide (NBPT) + DCD, urea + NBPT and urea, respectively, while the emission factor for urine alone was 0.33%. Calcium ammonium nitrate and urea did not interact differently with urine even when the urea included DCD. N2O losses could be reduced by switching from CAN to urea-based fertilisers

    My migraine voice survey. aA global study of disease burden among individuals with migraine for whom preventive treatments have failed

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    Background: Migraine is associated with many debilitating symptoms that affect daily functioning. My Migraine Voice is a large global cross-sectional study aimed at understanding the full burden and impact of migraine directly from patients suffering from ≥4 monthly migraine days (MMDs) with a history of prophylactic treatment failure. Methods: This study was conducted worldwide (31 countries across North and South Americas, Europe, the Middle East and Northern Africa, and the Asia-Pacific region) using an online survey administered to adults with migraine who reported ≥4 MMDs in the 3 months preceding survey administration, with pre-specified criteria of 90% having used preventive migraine treatment (80% with history of ≥1 treatment failure). Prophylactic treatment failure was defined as a reported change in preventive medication by individuals with migraine for any reason, at least once. Results: In total, 11,266 individuals participated in the survey. Seventy-four percent of the participants reported spending time in darkness/isolation due to migraine (average: 19 h/month). While 85% of all respondents reported negative aspects of living with migraine (feeling helpless, depressed, not understood), sleeping difficulties (83%), and fear of the next attack (55%), 57% shared ≥1 positive aspect (learning to cope, becoming a stronger person). Forty-nine percent reported feeling limited in daily activities throughout all migraine phases. Migraine impact on professional, private, or social domains was reported by 87% of respondents (51% in all domains). In the previous 12 months, 38% of respondents had visited the emergency department (average: 3.3 visits), whereas 23% stayed in hospital overnight (average: 3.2 nights) due to migraine. Conclusions: The burden of migraine is substantial among this cohort of individuals with at least 4 migraine days per month and for whom at least 1 preventive migraine treatment had failed. Interestingly, respondents reported some positive aspects in their migraine journey; the greater resilience and strength brought on by coping with migraine suggests that if future treatments could address existing unmet needs, these individuals with migraine will be able to maximize their contribution to society

    The role of client empathy in treatment outcome in a sample of adolescents referred to forensic youth psychiatric services

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    Starting from the assumption that empathy is crucial in the therapeutic process, the current study explored whether client empathy before treatment relates to treatment outcome, whether client empathy is subject to change in the first six months of treatment, whether such change relates to treatment outcome and whether therapist factors relate to possible changes in client empathy. In total 90 adolescents treated by 31 therapists at forensic psychiatric services participated in the study. Client empathy was assessed with self-report questionnaires of affective and cognitive empathy at intake and again at six months of treatment. Therapeutic change was rated by their therapist. Client empathy before treatment was not systematically related to treatment outcome. Cognitive empathy tended to improve during treatment, stronger in girls than boys, and depending in part on the therapist's gender: Under conditions of a male (not female) therapist boys reported less improvement in cognitive empathy than girls. The most consistent study result was that improvement in cognitive empathy contributed positively to treatment outcome. The study provides new data on the role of client empathy in the treatment of forensic youth psychiatric patients. If replicated, these findings have important implications for treatment and training in juvenile forensic psychiatry

    Headache yesterday in Europe

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    BACKGROUND: Surveys enquiring about burden of headache over a prior period of time (eg, 3 months) are subject to recall bias. To eliminate this as far as possible, we focused on presence and impact of headache on the preceding day (“headache yesterday”). METHODS: Adults (18-65 years) were surveyed from the general populations of Germany, Italy, Lithuania, Luxembourg and the Netherlands, from a work-force population in Spain and from mostly non-headache patient populations of Austria, France and UK. A study of non-responders in some countries allowed detection of potential participation bias where initial participation rates were low. RESULTS: Participation rates varied between 11% and 59% (mean 27%). Non-responder studies suggested that, because of participation bias, headache prevalence might be overestimated in initial responders by up to 2% (absolute). Across all countries, 1,422 of 8,271 participants (15-17%, depending on correction for participation bias) had headache yesterday lasting on average for 6 hours. It was bad or very bad in 56% of cases and caused absence from work or school in 6%. Among those who worked despite headache, 20% reported productivity reduced by >50%. Social activities were lost by 24%. Women (21%) were more likely than men (12%) to have headache yesterday, but impact was similar in the two genders. CONCLUSIONS: With recall biases avoided, our findings indicate that headache costs at least 0.7% of working capacity in Europe. This calculation takes into account that most of those who missed work could make up for this later, which, however, means that leisure and social activities are even more influenced by headache

    Bildsegmentation zur Untersuchung von Streulichtbildern bei der laseroptischen Diagnose von rheumatoider Arthritis

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    Optical imaging in biomedicine is governed by the light absorption and scattering interaction on microscopic and macroscopic constituents in the medium. Therefore, light scattering characteristics of human tissue correlates with the stage of some diseases. In the near infrared range the scattering event with the coefficient approximately two orders of magnitude greater than absorption plays a dominant role. The potential of an experimental laser diode based setup for the transillumination of rheumatoid finger joints and the pattern of the stray light detection are demonstrated. For evaluating the scattering light images a new non-local image segmentation method is presented. Regarding a noisy picture as a multicomponent mixture of gray scaled particles, this method minimizes a non-convex free energy functional under the constraint of mass conservation of the components. Contrary to constructing equilibrium distributions as steady states of an adequate evolution equation, a direct descent method for the free energy is used to separate the components of the image
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