899 research outputs found

    Climate Concern and Engagement: Large Face-to-Face and Online Polls by the Dutch non-profit Milieudefensie

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    Climate change mitigation depends on tracking public opinion across populations. Social scientists can collaborate with environmental organizations that conduct surveys among their audiences. We teamed up with the non-profit Milieudefensie, who surveyed Dutch attitudes towards climate change in 2019-2020. The large dataset had face-to-face (n = 3,102) and online interviews (n = 30,311) of urbanity, climate concern, policy preferences, interviewer-rated engagement with climate change, and behavior (whether the interviewee provided their email and phone number to the organization). To reveal the representativeness of these kinds of convenience samples, we tested whether attitudes and their associations with behaviors were similar to previous studies. Climate concern, preference for climate policy, and interviewer-rated engagement were high. In the online survey, 47% of respondents signed up for an email newsletter, and 7% provided their phone number. Higher climate concern and preference for climate policy predicted interviewer-rated engagement and behavior (weak to strong associations). Urbanity was not related to concern, policy preferences, or interviewer-rated engagement. Policy preferences did not differ between the face-to-face and online samples. The results provide convergent evidence to conventional online surveys. These Dutch residents appear slightly more engaged with systemic change to mitigate climate change than the general public.</p

    Nitrogen Budgets and Soil Nitrogen Stocks of Organic and Conventional Cropping Systems: Trade-Off between Efficiency and Sustainability of Nitrogen Use

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    Organic and conventional cropping systems differ in the nature and amounts of nitrogen (N) inputs, which may affect efficiency and sustainability of N use. In the DOK (bio-Dynamic, bio-Organic, Konventionell) field experiment, organic and conventional cropping systems have been compared since 1978 at two fertilization levels. Nitrogen inputs via manure and/or mineral fertilizers, and N exports from plots with harvested products have throughout been recorded. For all treatments, N outputs with harvests have exceeded the inputs with fertilizers. Over the past years, symbiotic N2 fixation by soybean and clover grown in the trial has additionally been assessed, indicating average annual inputs of about 100 kg ha-1 yr-1 of N fixed from the atmosphere. Soil surface budgets opposing N inputs via fertilization, symbiotic fixation, seeds and deposition to N outputs via harvested products have been computed at the plot level for the duration from 1985 to 2012. The resulting balances range from negative values of about -20 kg N ha-1 yr-1 (where outputs exceed the sum of said N inputs) to surpluses of about +50 kg N ha-1 yr-1. The budget based N use efficiency (NUE; N output via harvested products divided by sum of N inputs) in the case of negative balances suggests irrationally high NUE (>100%), while positive balances are related to lower NUE for treatments with inputs exceeding outputs. Negative balances, however, indicate soil N mining, while surpluses point to a risk of N losses, and/or N accumulation in the soil. Estimation of soil N stock changes based on yearly total N concentration measurements in the topsoil layer is currently ongoing. Preliminary results suggest that soil N stocks in the topsoil decreased under all treatments more than expected from the N balance, and that positive N balances are needed to maintain topsoil N stocks. An increase in soil N concentration was observed in none of the treatments. In conclusion, the results indicate an efficiency-sustainability trade-off. Treatments with a higher NUE lose more soil stock N than those with a lower NUE. Treatments with lower NUE indicate higher N losses from the studied crop-topsoil system. Sustainable soil N management in addition to organic fertilizer inputs might at this site require reduced soil tillage. The significance of N contained in deeper soil layers, and deep rooting crops in recovering leached N should as well be investigated

    The Quantum Skyrmion in Representations of General Dimension

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    The representations of general dimension are constructed for the SU(2)SU(2) Skyrme model, treated quantum mechanically {\it ab initio. } This quantum Skyrme model has a negative mass term correction, that is not present in the classical Hamiltonian. The magnitude of the quantum mechanical mass correction increases with the dimension of the representation of the SU(2)SU(2) group. In the case of a 5-dimensional representation it is possible to obtain satisfactory predictions for the nucleon mass with the empirical value for the pion decay constant.Comment: Plain latex, 15 page

    Hepatitis-B- und -C-assoziierte Glomerulonephritiden

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    Zusammenfassung: Virale Hepatitiden sind häufig mit extrahepatischen Manifestationen assoziiert. Bei der HepatitisB ist die membranöse Glomerulonephritis (GN) die häufigste histologische Diagnose. Im Rahmen der HepatitisC wird vorwiegend eine membranoproliferative GN mit oder ohne gemischte Kryoglobulinämie beobachtet. Eine zentrale pathogenetische Rolle spielen Immunkomplexe (virale Antigene, antivirale Antikörper, bei Kryoglobulinämie auch Rheumafaktoren). Diese Komplexe werden in der Niere abgelagert und aktivieren Komplement, was schließlich zum Nierenschaden führt. Therapeutisch zentral ist die antivirale Therapie mit dem Ziel der Antigenelimination. Im Falle der HepatitisB kann eine Therapie mit IFNα durchgeführt werden, alternativ mit Lamivudin. Eine immunsuppressive Therapie steht eher im Hintergrund. Bei der HepatitisC ist die Standardtherapie IFNα in Kombination mit Ribavirin. Bei einer zusätzlichen Kryoglobulinämie besteht die Alternative einer Therapie mit Rituximab, bei schwerem Verlauf mit Plasmapherese, Steroiden und Cyclophosphamid. Bei vollständiger Elimination der Virusreplikation ist die Prognose dieser sekundären GN günsti

    Anti-Treponema pallidum IgA response as a potential diagnostic marker of syphilis

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    Objectives: Serological tests for syphilis detect mainly total Ig, IgM or IgG antibodies. We aimed to evaluate the specific IgA response in syphilis patients according to disease stage. Methods: A serum IgA-enzyme immunoassay was developed using commercially available microplates coated with recombinant treponemal antigens and an anti-IgA-conjugate. To define a cut-off, we used 91 syphilis positive and 136 negative sera previously defined by the rapid plasma reagin and the Treponema pallidum particle agglutination results. Then we determined the intra- and inter-assay precisions, diagnostic sensitivity according to the clinical stage (in 66, 55 and 42 sera from primary, secondary and latent syphilis patients, respectively) and specificity (in 211 sera from people with conditions different to syphilis). IgA values were further measured in 71 sera from patients with previously treated syphilis. Results: The newly developed IgA-enzyme immunoassay showed a good discrimination between negative and positive samples with intra- and inter-assay variation coefficients <20%. The sensitivity was 80.3% (95% CI, 70.0-90.6), 100.0% (95% CI, 99.1-100.0) and 95.2% (95% CI, 87.6-100.0) in primary, secondary and latent syphilis, respectively, and the specificity was 98.1% (95% CI, 96.0-100.0). Further, IgA values were negative in 61.3% (38/62) of patients with previously treated syphilis. Discussion: Our findings suggest serum IgA as a sensitive and specific marker of syphilis and its detection could be used as a screening assay for active infection. Further evaluation is needed in prospective longitudinal field studies

    Symbiotic N2 fixation by soybean in organic and conventional cropping systems estimated by 15N dilution and 15N natural abundance

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    Nitrogen (N) is often the most limiting nutrient in organic cropping systems. N2 fixing crops present an important option to improve N supply and to maintain soil fertility. In a field experiment, we investigated whether the lower N fertilization level and higher soil microbial activity in organic than conventional systems affected symbiotic N2 fixation by soybean (Glycine max, var. Maple Arrow) growing in 2004 in plots that were since 1978 under the following systems: bio-dynamic (DYN); bio-organic (ORG); conventional with organic and mineral fertilizers (CON); CON with exclusively mineral fertilizers (MIN); non-fertilized control (NON). We estimated the percentage of legume N derived from the atmosphere (%Ndfa) by the natural abundance (NA) method. For ORG and MIN we additionally applied the enriched 15N isotope dilution method (ID) based on residual mineral and organic 15N labeled fertilizers that were applied in 2003 in microplots installed in ORG and MIN plots. These different enrichment treatments resulted in equal %Ndfa values. The %Ndfa obtained by NA for ORG and MIN was confirmed by the ID method, with similar variation. However, as plant growth was restricted by the microplot frames the NA technique provided more accurate estimates of the quantities of symbiotically fixed N2 (Nfix). At maturity of soybean the %Ndfa ranged from 24 to 54%. It decreased in the order ORG>CON>DYN>NON>MIN, with significantly lowest value for MIN. Corresponding Nfix in above ground plant material ranged from 15 to 26g Nm-2, with a decreasing trend in the order DYN=ORG>CON>MIN>NON. For all treatments, the N withdrawal by harvested grains was greater than Nfix. This shows that at the low to medium %Ndfa, soybeans did not improve the N supply to any system but removed significant amounts of soil N. High-soil N mineralization and/or low-soil P availability may have limited symbiotic N2 fixatio

    Failed coronary artery bypass anastomosis detected by intraoperative coronary flow measurement

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    Objectives: To assess intraoperative flow of arterial and venous coronary grafts after myocardial revascularization which may allow early detection of low flow situations, especially during minimally invasive coronary bypass surgery (MIDCAB), and lead to immediate correction of technical problems. Methods: In two patients with severe and diffuse multi-vessel disease the left internal mammary artery (IMA) was connected to the left anterior descending artery (LAD). During reperfusion, the flow was measured in the IMA and vein grafts using a transit time flow meter. Results: In both cases the IMA showed only a systolic pendulating flow curve with a mean flow of 0-1 ml/min and a high resistance. Manual IMA assessment revealed an adequate pulsation. Both distal IMA anastomoses were re-explored on cardiopulmonary bypass yielding an initial flow of 7 and 14 ml/min, respectively. After treatment with papaverine/adenosine the IMA flow increased from 7 to 26 ml/min (coronary flow reserve (CFR)=3.7) and from 14 to 46 ml/min (CFR=3.3), respectively. Conclusion: Intraoperative flow assessment of IMA and venous bypass grafts can be recommended to monitor flow; especially during MIDCAB procedure
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