28 results on '"M. Kuhner"'
Search Results
2. Thrombotischer Verschluss der extrakorporalen Zirkulation während hepatischer Chemosaturation trotz zielgerechter Antikoagulation
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M. Kuhner, B. Tan, M. O. Fiedler, O. Biecker, B. Klein, D. H. Chang, M. A. Weigand, and M. Dietrich
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ZusammenfassungDie perkutane hepatische Chemosaturation ist eine Behandlungsoption bei nichtresektablen primären oder sekundären Lebertumoren. Dabei wird der Bereich der Lebervenenmündung der Vena cava inferior (VCI) mittels 2 Ballons von der Zirkulation isoliert, sodass die systemische Verteilung des über die Leberarterie applizierten Chemotherapeutikums Melphalan verhindert wird. Nach Passage der Leber und venöser Drainage aus der retrohepatischen VCI durchläuft das chemosaturierte Blut 2 parallel geschaltete extrakorporale Filter. Anschließend wird das gereinigte Blut jugulär rückgeführt. Das Verfahren geht oft mit einer ausgeprägten hämodynamischen Instabilität einher, deren Ursache nicht abschließend geklärt ist. Zusätzlich stellt das Gerinnungsmanagement eine Herausforderung dar. Die Autoren berichten von einem Fall, bei dem sich trotz ausreichender „activated clotting time“ (ACT) ein Thrombus im rückführenden Schenkel der extrakorporalen Zirkulation bildete. Gezielte Problemsuche und -lösung waren parallel zur hämodynamischen Stabilisierung und interdisziplinären Zusammenarbeit notwendig, um die Intervention erfolgreich durchzuführen und der Patientin eine sichere Therapie zukommen zu lassen.
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- 2022
3. [Focus on emergency medicine 2021/2022-Summary of selected emergency medicine studies]
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S, Katzenschlager, M, Obermaier, M, Kuhner, W, Spöttl, M, Dietrich, M A, Weigand, F, Weilbacher, and E, Popp
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- 2022
4. [Thrombotic occlusion of the extracorporeal circulation during hepatic chemosaturation despite targeted anticoagulation : A case report]
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M, Kuhner, B, Tan, M O, Fiedler, O, Biecker, B, Klein, D H, Chang, M A, Weigand, and M, Dietrich
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Extracorporeal Circulation ,Liver Neoplasms ,Humans ,Anticoagulants ,Melphalan - Abstract
Percutaneous hepatic chemosaturation is a treatment option for unresectable primary or secondary liver tumors. In this procedure the part of the inferior vena cava (VCI) that collects blood from the hepatic veins is isolated using a double balloon catheter. Like this, systemic distribution of the chemotherapeutic agent melphalan which is administered via the hepatic artery can be prevented. After passage through the liver and drainage from the retrohepatic VCI, the chemosaturated blood passes through two extracorporeal filters. Subsequently, the filtered blood is returned via the jugular vein. The procedure is often accompanied by severe hemodynamic instability, the cause of which is still not completely understood. In addition, coagulation management of extracorporeal circulation is often challenging. The authors report a case in which a thrombus formed in the returning leg of the extracorporeal circulation despite sufficient activated clotting time (ACT). Targeted problem search and resolution were necessary simultaneously to hemodynamic stabilization and interdisciplinary collaboration to successfully perform the intervention and provide the patient with safe treatment.Die perkutane hepatische Chemosaturation ist eine Behandlungsoption bei nichtresektablen primären oder sekundären Lebertumoren. Dabei wird der Bereich der Lebervenenmündung der Vena cava inferior (VCI) mittels 2 Ballons von der Zirkulation isoliert, sodass die systemische Verteilung des über die Leberarterie applizierten Chemotherapeutikums Melphalan verhindert wird. Nach Passage der Leber und venöser Drainage aus der retrohepatischen VCI durchläuft das chemosaturierte Blut 2 parallel geschaltete extrakorporale Filter. Anschließend wird das gereinigte Blut jugulär rückgeführt. Das Verfahren geht oft mit einer ausgeprägten hämodynamischen Instabilität einher, deren Ursache nicht abschließend geklärt ist. Zusätzlich stellt das Gerinnungsmanagement eine Herausforderung dar. Die Autoren berichten von einem Fall, bei dem sich trotz ausreichender „activated clotting time“ (ACT) ein Thrombus im rückführenden Schenkel der extrakorporalen Zirkulation bildete. Gezielte Problemsuche und -lösung waren parallel zur hämodynamischen Stabilisierung und interdisziplinären Zusammenarbeit notwendig, um die Intervention erfolgreich durchzuführen und der Patientin eine sichere Therapie zukommen zu lassen.
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- 2022
5. The consolidated European synthesis of CO2 emissions and removals for the European Union and United Kingdom: 1990–2020
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M. J. McGrath, A. M. R. Petrescu, P. Peylin, R. M. Andrew, B. Matthews, F. Dentener, J. Balkovič, V. Bastrikov, M. Becker, G. Broquet, P. Ciais, A. Fortems-Cheiney, R. Ganzenmüller, G. Grassi, I. Harris, M. Jones, J. Knauer, M. Kuhnert, G. Monteil, S. Munassar, P. I. Palmer, G. P. Peters, C. Qiu, M.-J. Schelhaas, O. Tarasova, M. Vizzarri, K. Winkler, G. Balsamo, A. Berchet, P. Briggs, P. Brockmann, F. Chevallier, G. Conchedda, M. Crippa, S. N. C. Dellaert, H. A. C. Denier van der Gon, S. Filipek, P. Friedlingstein, R. Fuchs, M. Gauss, C. Gerbig, D. Guizzardi, D. Günther, R. A. Houghton, G. Janssens-Maenhout, R. Lauerwald, B. Lerink, I. T. Luijkx, G. Moulas, M. Muntean, G.-J. Nabuurs, A. Paquirissamy, L. Perugini, W. Peters, R. Pilli, J. Pongratz, P. Regnier, M. Scholze, Y. Serengil, P. Smith, E. Solazzo, R. L. Thompson, F. N. Tubiello, T. Vesala, and S. Walther
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Environmental sciences ,GE1-350 ,Geology ,QE1-996.5 - Abstract
Quantification of land surface–atmosphere fluxes of carbon dioxide (CO2) and their trends and uncertainties is essential for monitoring progress of the EU27+UK bloc as it strives to meet ambitious targets determined by both international agreements and internal regulation. This study provides a consolidated synthesis of fossil sources (CO2 fossil) and natural (including formally managed ecosystems) sources and sinks over land (CO2 land) using bottom-up (BU) and top-down (TD) approaches for the European Union and United Kingdom (EU27+UK), updating earlier syntheses (Petrescu et al., 2020, 2021). Given the wide scope of the work and the variety of approaches involved, this study aims to answer essential questions identified in the previous syntheses and understand the differences between datasets, particularly for poorly characterized fluxes from managed and unmanaged ecosystems. The work integrates updated emission inventory data, process-based model results, data-driven categorical model results, and inverse modeling estimates, extending the previous period 1990–2018 to the year 2020 to the extent possible. BU and TD products are compared with the European national greenhouse gas inventory (NGHGI) reported by parties including the year 2019 under the United Nations Framework Convention on Climate Change (UNFCCC). The uncertainties of the EU27+UK NGHGI were evaluated using the standard deviation reported by the EU member states following the guidelines of the Intergovernmental Panel on Climate Change (IPCC) and harmonized by gap-filling procedures. Variation in estimates produced with other methods, such as atmospheric inversion models (TD) or spatially disaggregated inventory datasets (BU), originate from within-model uncertainty related to parameterization as well as structural differences between models. By comparing the NGHGI with other approaches, key sources of differences between estimates arise primarily in activities. System boundaries and emission categories create differences in CO2 fossil datasets, while different land use definitions for reporting emissions from land use, land use change, and forestry (LULUCF) activities result in differences for CO2 land. The latter has important consequences for atmospheric inversions, leading to inversions reporting stronger sinks in vegetation and soils than are reported by the NGHGI. For CO2 fossil emissions, after harmonizing estimates based on common activities and selecting the most recent year available for all datasets, the UNFCCC NGHGI for the EU27+UK accounts for 926 ± 13 Tg C yr−1, while eight other BU sources report a mean value of 948 [937,961] Tg C yr−1 (25th, 75th percentiles). The sole top-down inversion of fossil emissions currently available accounts for 875 Tg C in this same year, a value outside the uncertainty of both the NGHGI and bottom-up ensemble estimates and for which uncertainty estimates are not currently available. For the net CO2 land fluxes, during the most recent 5-year period including the NGHGI estimates, the NGHGI accounted for −91 ± 32 Tg C yr−1, while six other BU approaches reported a mean sink of −62 [-117,-49] Tg C yr−1, and a 15-member ensemble of dynamic global vegetation models (DGVMs) reported −69 [-152,-5] Tg C yr−1. The 5-year mean of three TD regional ensembles combined with one non-ensemble inversion of −73 Tg C yr−1 has a slightly smaller spread (0th–100th percentiles of [-135,+45] Tg C yr−1), and it was calculated after removing net land–atmosphere CO2 fluxes caused by lateral transport of carbon (crop trade, wood trade, river transport, and net uptake from inland water bodies), resulting in increased agreement with the NGHGI and bottom-up approaches. Results at the category level (Forest Land, Cropland, Grassland) generally show good agreement between the NGHGI and category-specific models, but results for DGVMs are mixed. Overall, for both CO2 fossil and net CO2 land fluxes, we find that current independent approaches are consistent with the NGHGI at the scale of the EU27+UK. We conclude that CO2 emissions from fossil sources have decreased over the past 30 years in the EU27+UK, while land fluxes are relatively stable: positive or negative trends larger (smaller) than 0.07 (−0.61) Tg C yr−2 can be ruled out for the NGHGI. In addition, a gap on the order of 1000 Tg C yr−1 between CO2 fossil emissions and net CO2 uptake by the land exists regardless of the type of approach (NGHGI, TD, BU), falling well outside all available estimates of uncertainties. However, uncertainties in top-down approaches to estimate CO2 fossil emissions remain uncharacterized and are likely substantial, in addition to known uncertainties in top-down estimates of the land fluxes. The data used to plot the figures are available at https://doi.org/10.5281/zenodo.8148461 (McGrath et al., 2023).
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- 2023
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6. Modeling Denitrification: Can We Report What We Don't Know?
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B. Grosz, A. Matson, K. Butterbach‐Bahl, T. Clough, E. A. Davidson, R. Dechow, S. DelGrosso, E. Diamantopoulos, P. Dörsch, E. Haas, H. He, C. V. Henri, D. Hui, K. Kleineidam, D. Kraus, M. Kuhnert, J. Léonard, C. Müller, S. O. Petersen, D. Sihi, I. Vogeler, R. Well, J. Yeluripati, J. Zhang, and C. Scheer
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denitrification ,N‐cycle ,N2 ,biogeochemical models ,nitrogen budget ,Geology ,QE1-996.5 ,Geophysics. Cosmic physics ,QC801-809 - Abstract
Abstract Biogeochemical models simulate soil nitrogen (N) turnover and are often used to assess N losses through denitrification. Though models simulate a complete N budget, often only a subset of N pools/fluxes (i.e., N2O, NO3−, NH3, NOx) are published since the full budget cannot be validated with measured data. Field studies rarely include full N balances, especially N2 fluxes, which are difficult to quantify. Limiting publication of modeling results based on available field data represents a missed opportunity to improve the understanding of modeled processes. We propose that the modeler community support publication of all simulated N pools and processes in future studies.
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- 2023
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7. The consolidated European synthesis of CH4 and N2O emissions for the European Union and United Kingdom: 1990–2019
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A. M. R. Petrescu, C. Qiu, M. J. McGrath, P. Peylin, G. P. Peters, P. Ciais, R. L. Thompson, A. Tsuruta, D. Brunner, M. Kuhnert, B. Matthews, P. I. Palmer, O. Tarasova, P. Regnier, R. Lauerwald, D. Bastviken, L. Höglund-Isaksson, W. Winiwarter, G. Etiope, T. Aalto, G. Balsamo, V. Bastrikov, A. Berchet, P. Brockmann, G. Ciotoli, G. Conchedda, M. Crippa, F. Dentener, C. D. Groot Zwaaftink, D. Guizzardi, D. Günther, J.-M. Haussaire, S. Houweling, G. Janssens-Maenhout, M. Kouyate, A. Leip, A. Leppänen, E. Lugato, M. Maisonnier, A. J. Manning, T. Markkanen, J. McNorton, M. Muntean, G. D. Oreggioni, P. K. Patra, L. Perugini, I. Pison, M. T. Raivonen, M. Saunois, A. J. Segers, P. Smith, E. Solazzo, H. Tian, F. N. Tubiello, T. Vesala, G. R. van der Werf, C. Wilson, and S. Zaehle
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Environmental sciences ,GE1-350 ,Geology ,QE1-996.5 - Abstract
Knowledge of the spatial distribution of the fluxes of greenhouse gases (GHGs) and their temporal variability as well as flux attribution to natural and anthropogenic processes is essential to monitoring the progress in mitigating anthropogenic emissions under the Paris Agreement and to inform its global stocktake. This study provides a consolidated synthesis of CH4 and N2O emissions using bottom-up (BU) and top-down (TD) approaches for the European Union and UK (EU27 + UK) and updates earlier syntheses (Petrescu et al., 2020, 2021). The work integrates updated emission inventory data, process-based model results, data-driven sector model results and inverse modeling estimates, and it extends the previous period of 1990–2017 to 2019. BU and TD products are compared with European national greenhouse gas inventories (NGHGIs) reported by parties under the United Nations Framework Convention on Climate Change (UNFCCC) in 2021. Uncertainties in NGHGIs, as reported to the UNFCCC by the EU and its member states, are also included in the synthesis. Variations in estimates produced with other methods, such as atmospheric inversion models (TD) or spatially disaggregated inventory datasets (BU), arise from diverse sources including within-model uncertainty related to parameterization as well as structural differences between models. By comparing NGHGIs with other approaches, the activities included are a key source of bias between estimates, e.g., anthropogenic and natural fluxes, which in atmospheric inversions are sensitive to the prior geospatial distribution of emissions. For CH4 emissions, over the updated 2015–2019 period, which covers a sufficiently robust number of overlapping estimates, and most importantly the NGHGIs, the anthropogenic BU approaches are directly comparable, accounting for mean emissions of 20.5 Tg CH4 yr−1 (EDGARv6.0, last year 2018) and 18.4 Tg CH4 yr−1 (GAINS, last year 2015), close to the NGHGI estimates of 17.5±2.1 Tg CH4 yr−1. TD inversion estimates give higher emission estimates, as they also detect natural emissions. Over the same period, high-resolution regional TD inversions report a mean emission of 34 Tg CH4 yr−1. Coarser-resolution global-scale TD inversions result in emission estimates of 23 and 24 Tg CH4 yr−1 inferred from GOSAT and surface (SURF) network atmospheric measurements, respectively. The magnitude of natural peatland and mineral soil emissions from the JSBACH–HIMMELI model, natural rivers, lake and reservoir emissions, geological sources, and biomass burning together could account for the gap between NGHGI and inversions and account for 8 Tg CH4 yr−1. For N2O emissions, over the 2015–2019 period, both BU products (EDGARv6.0 and GAINS) report a mean value of anthropogenic emissions of 0.9 Tg N2O yr−1, close to the NGHGI data (0.8±55 % Tg N2O yr−1). Over the same period, the mean of TD global and regional inversions was 1.4 Tg N2O yr−1 (excluding TOMCAT, which reported no data). The TD and BU comparison method defined in this study can be operationalized for future annual updates for the calculation of CH4 and N2O budgets at the national and EU27 + UK scales. Future comparability will be enhanced with further steps involving analysis at finer temporal resolutions and estimation of emissions over intra-annual timescales, which is of great importance for CH4 and N2O, and may help identify sector contributions to divergence between prior and posterior estimates at the annual and/or inter-annual scale. Even if currently comparison between CH4 and N2O inversion estimates and NGHGIs is highly uncertain because of the large spread in the inversion results, TD inversions inferred from atmospheric observations represent the most independent data against which inventory totals can be compared. With anticipated improvements in atmospheric modeling and observations, as well as modeling of natural fluxes, TD inversions may arguably emerge as the most powerful tool for verifying emission inventories for CH4, N2O and other GHGs. The referenced datasets related to figures are visualized at https://doi.org/10.5281/zenodo.7553800 (Petrescu et al., 2023).
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- 2023
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8. P843Risk prediction in stable cardiovascular disease using a single biomarker strategy with high-sensitivity cardiac troponin T compared to the HeartSCORE
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Moritz Biener, Hugo A. Katus, Evangelos Giannitsis, M. Kuhner, Thomas A Zelniker, Matthias Mueller-Hennessen, and Mehrshad Vafaie
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medicine.medical_specialty ,Cardiac troponin ,business.industry ,Internal medicine ,medicine ,Cardiology ,Biomarker (medicine) ,Disease ,Sensitivity (control systems) ,Cardiology and Cardiovascular Medicine ,HeartScore ,business - Published
- 2017
9. Management-induced changes in soil organic carbon on global croplands
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K. Karstens, B. L. Bodirsky, J. P. Dietrich, M. Dondini, J. Heinke, M. Kuhnert, C. Müller, S. Rolinski, P. Smith, I. Weindl, H. Lotze-Campen, and A. Popp
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Ecology ,QH540-549.5 ,Life ,QH501-531 ,Geology ,QE1-996.5 - Abstract
Soil organic carbon (SOC), one of the largest terrestrial carbon (C) stocks on Earth, has been depleted by anthropogenic land cover change and agricultural management. However, the latter has so far not been well represented in global C stock assessments. While SOC models often simulate detailed biochemical processes that lead to the accumulation and decay of SOC, the management decisions driving these biophysical processes are still little investigated at the global scale. Here we develop a spatially explicit data set for agricultural management on cropland, considering crop production levels, residue returning rates, manure application, and the adoption of irrigation and tillage practices. We combine it with a reduced-complexity model based on the Intergovernmental Panel on Climate Change (IPCC) tier 2 method to create a half-degree resolution data set of SOC stocks and SOC stock changes for the first 30 cm of mineral soils. We estimate that, due to arable farming, soils have lost around 34.6 GtC relative to a counterfactual hypothetical natural state in 1975. Within the period 1975–2010, this SOC debt continued to expand by 5 GtC (0.14 GtC yr−1) to around 39.6 GtC. However, accounting for historical management led to 2.1 GtC fewer (0.06 GtC yr−1) emissions than under the assumption of constant management. We also find that management decisions have influenced the historical SOC trajectory most strongly by residue returning, indicating that SOC enhancement by biomass retention may be a promising negative emissions technique. The reduced-complexity SOC model may allow us to simulate management-induced SOC enhancement – also within computationally demanding integrated (land use) assessment modeling.
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- 2022
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10. The consolidated European synthesis of CH4 and N2O emissions for the European Union and United Kingdom: 1990–2017
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A. M. R. Petrescu, C. Qiu, P. Ciais, R. L. Thompson, P. Peylin, M. J. McGrath, E. Solazzo, G. Janssens-Maenhout, F. N. Tubiello, P. Bergamaschi, D. Brunner, G. P. Peters, L. Höglund-Isaksson, P. Regnier, R. Lauerwald, D. Bastviken, A. Tsuruta, W. Winiwarter, P. K. Patra, M. Kuhnert, G. D. Oreggioni, M. Crippa, M. Saunois, L. Perugini, T. Markkanen, T. Aalto, C. D. Groot Zwaaftink, Y. Yao, C. Wilson, G. Conchedda, D. Günther, A. Leip, P. Smith, J.-M. Haussaire, A. Leppänen, A. J. Manning, J. McNorton, P. Brockmann, and A. J. Dolman
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Environmental sciences ,GE1-350 ,Geology ,QE1-996.5 - Abstract
Reliable quantification of the sources and sinks of greenhouse gases, together with trends and uncertainties, is essential to monitoring the progress in mitigating anthropogenic emissions under the Paris Agreement. This study provides a consolidated synthesis of CH4 and N2O emissions with consistently derived state-of-the-art bottom-up (BU) and top-down (TD) data sources for the European Union and UK (EU27 + UK). We integrate recent emission inventory data, ecosystem process-based model results and inverse modeling estimates over the period 1990–2017. BU and TD products are compared with European national greenhouse gas inventories (NGHGIs) reported to the UN climate convention UNFCCC secretariat in 2019. For uncertainties, we used for NGHGIs the standard deviation obtained by varying parameters of inventory calculations, reported by the member states (MSs) following the recommendations of the IPCC Guidelines. For atmospheric inversion models (TD) or other inventory datasets (BU), we defined uncertainties from the spread between different model estimates or model-specific uncertainties when reported. In comparing NGHGIs with other approaches, a key source of bias is the activities included, e.g., anthropogenic versus anthropogenic plus natural fluxes. In inversions, the separation between anthropogenic and natural emissions is sensitive to the geospatial prior distribution of emissions. Over the 2011–2015 period, which is the common denominator of data availability between all sources, the anthropogenic BU approaches are directly comparable, reporting mean emissions of 20.8 Tg CH4 yr−1 (EDGAR v5.0) and 19.0 Tg CH4 yr−1 (GAINS), consistent with the NGHGI estimates of 18.9 ± 1.7 Tg CH4 yr−1. The estimates of TD total inversions give higher emission estimates, as they also include natural emissions. Over the same period regional TD inversions with higher-resolution atmospheric transport models give a mean emission of 28.8 Tg CH4 yr−1. Coarser-resolution global TD inversions are consistent with regional TD inversions, for global inversions with GOSAT satellite data (23.3 Tg CH4 yr−1) and surface network (24.4 Tg CH4 yr−1). The magnitude of natural peatland emissions from the JSBACH–HIMMELI model, natural rivers and lakes emissions, and geological sources together account for the gap between NGHGIs and inversions and account for 5.2 Tg CH4 yr−1. For N2O emissions, over the 2011–2015 period, both BU approaches (EDGAR v5.0 and GAINS) give a mean value of anthropogenic emissions of 0.8 and 0.9 Tg N2O yr−1, respectively, agreeing with the NGHGI data (0.9 ± 0.6 Tg N2O yr−1). Over the same period, the average of the three total TD global and regional inversions was 1.3 ± 0.4 and 1.3 ± 0.1 Tg N2O yr−1, respectively. The TD and BU comparison method defined in this study can be operationalized for future yearly updates for the calculation of CH4 and N2O budgets both at the EU+UK scale and at the national scale. The referenced datasets related to figures are visualized at https://doi.org/10.5281/zenodo.4590875 (Petrescu et al., 2020b).
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- 2021
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11. The consolidated European synthesis of CO2 emissions and removals for the European Union and United Kingdom: 1990–2018
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A. M. R. Petrescu, M. J. McGrath, R. M. Andrew, P. Peylin, G. P. Peters, P. Ciais, G. Broquet, F. N. Tubiello, C. Gerbig, J. Pongratz, G. Janssens-Maenhout, G. Grassi, G.-J. Nabuurs, P. Regnier, R. Lauerwald, M. Kuhnert, J. Balkovič, M.-J. Schelhaas, H. A. C. Denier van der Gon, E. Solazzo, C. Qiu, R. Pilli, I. B. Konovalov, R. A. Houghton, D. Günther, L. Perugini, M. Crippa, R. Ganzenmüller, I. T. Luijkx, P. Smith, S. Munassar, R. L. Thompson, G. Conchedda, G. Monteil, M. Scholze, U. Karstens, P. Brockmann, and A. J. Dolman
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Environmental sciences ,GE1-350 ,Geology ,QE1-996.5 - Abstract
Reliable quantification of the sources and sinks of atmospheric carbon dioxide (CO2), including that of their trends and uncertainties, is essential to monitoring the progress in mitigating anthropogenic emissions under the Kyoto Protocol and the Paris Agreement. This study provides a consolidated synthesis of estimates for all anthropogenic and natural sources and sinks of CO2 for the European Union and UK (EU27 + UK), derived from a combination of state-of-the-art bottom-up (BU) and top-down (TD) data sources and models. Given the wide scope of the work and the variety of datasets involved, this study focuses on identifying essential questions which need to be answered to properly understand the differences between various datasets, in particular with regards to the less-well-characterized fluxes from managed ecosystems. The work integrates recent emission inventory data, process-based ecosystem model results, data-driven sector model results and inverse modeling estimates over the period 1990–2018. BU and TD products are compared with European national greenhouse gas inventories (NGHGIs) reported under the UNFCCC in 2019, aiming to assess and understand the differences between approaches. For the uncertainties in NGHGIs, we used the standard deviation obtained by varying parameters of inventory calculations, reported by the member states following the IPCC Guidelines. Variation in estimates produced with other methods, like atmospheric inversion models (TD) or spatially disaggregated inventory datasets (BU), arises from diverse sources including within-model uncertainty related to parameterization as well as structural differences between models. In comparing NGHGIs with other approaches, a key source of uncertainty is that related to different system boundaries and emission categories (CO2 fossil) and the use of different land use definitions for reporting emissions from land use, land use change and forestry (LULUCF) activities (CO2 land). At the EU27 + UK level, the NGHGI (2019) fossil CO2 emissions (including cement production) account for 2624 Tg CO2 in 2014 while all the other seven bottom-up sources are consistent with the NGHGIs and report a mean of 2588 (± 463 Tg CO2). The inversion reports 2700 Tg CO2 (± 480 Tg CO2), which is well in line with the national inventories. Over 2011–2015, the CO2 land sources and sinks from NGHGI estimates report −90 Tg C yr−1 ± 30 Tg C yr−1 while all other BU approaches report a mean sink of −98 Tg C yr−1 (± 362 Tg of C from dynamic global vegetation models only). For the TD model ensemble results, we observe a much larger spread for regional inversions (i.e., mean of 253 Tg C yr−1 ± 400 Tg C yr−1). This concludes that (a) current independent approaches are consistent with NGHGIs and (b) their uncertainty is too large to allow a verification because of model differences and probably also because of the definition of “CO2 flux” obtained from different approaches. The referenced datasets related to figures are visualized at https://doi.org/10.5281/zenodo.4626578 (Petrescu et al., 2020a).
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- 2021
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12. Relative effectiveness of various alternating frequencies of a power toothbrush
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Peter Raetzke and M. Kuhner
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Male ,Toothbrushing ,Analysis of Variance ,Surface Properties ,Dental Plaque ,Reproducibility of Results ,Brush ,Pilot Projects ,Plaque growth ,Efficiency ,Equipment Design ,Ridit scoring ,Crossover study ,Power (physics) ,law.invention ,Electric Power Supplies ,Double-Blind Method ,law ,Statistics ,Power toothbrush ,Humans ,Periodontics ,Female ,Frequency distribution ,Mathematics - Abstract
The influence on plaque-removing efficiency of the alternating frequency of a powered brush has never been established. In the present study, a mechanical brush was tested at various alternations per minute (F1 = 2100, F2 = 2500, F3 = 3500). A double-blind, randomized, triple crossover design was applied. After a plaque growth phase, the test brushes were used under supervision for 90 s and the remaining plaque scored. A ridit analysis yielded significant differences between F2 and F1/F3. Odds ratios and frequency distributions demonstrated a clinically meaningful advantage for F2. Subjective evaluation by the participants confirmed the positive performance of F2. The results can be generalized in 3 ways: (1) the alternating frequency of a power brush influences its effectiveness, (2) high frequencies are not generally superior, (3) the test brush has its optimal cleaning efficiency at F2, which does not necessarily need to be true for other brands. It seems imperative to determine the optimal frequency for any new brush in a controlled study.
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- 1993
13. Impact of droughts on the carbon cycle in European vegetation: a probabilistic risk analysis using six vegetation models
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M. Van Oijen, J. Balkovi, C. Beer, D. R. Cameron, P. Ciais, W. Cramer, T. Kato, M. Kuhnert, R. Martin, R. Myneni, A. Rammig, S. Rolinski, J.-F. Soussana, K. Thonicke, M. Van der Velde, and L. Xu
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Ecology ,QH540-549.5 ,Life ,QH501-531 ,Geology ,QE1-996.5 - Abstract
We analyse how climate change may alter risks posed by droughts to carbon fluxes in European ecosystems. The approach follows a recently proposed framework for risk analysis based on probability theory. In this approach, risk is quantified as the product of hazard probability and ecosystem vulnerability. The probability of a drought hazard is calculated here from the Standardized Precipitation–Evapotranspiration Index (SPEI). Vulnerability is calculated from the response to drought simulated by process-based vegetation models. We use six different models: three for generic vegetation (JSBACH, LPJmL, ORCHIDEE) and three for specific ecosystems (Scots pine forests: BASFOR; winter wheat fields: EPIC; grasslands: PASIM). The periods 1971–2000 and 2071–2100 are compared. Climate data are based on gridded observations and on output from the regional climate model REMO using the SRES A1B scenario. The risk analysis is carried out for ~ 18 000 grid cells of 0.25 × 0.25° across Europe. For each grid cell, drought vulnerability and risk are quantified for five seasonal variables: net primary and ecosystem productivity (NPP, NEP), heterotrophic respiration (Rh), soil water content and evapotranspiration. In this analysis, climate change leads to increased drought risks for net primary productivity in the Mediterranean area: five of the models estimate that risk will exceed 15%. The risks increase mainly because of greater drought probability; ecosystem vulnerability will increase to a lesser extent. Because NPP will be affected more than Rh, future carbon sequestration (NEP) will also be at risk predominantly in southern Europe, with risks exceeding 0.25 g C m−2 d−1 according to most models, amounting to reductions in carbon sequestration of 20 to 80%.
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- 2014
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14. Environmental change impacts on the C- and N-cycle of European forests: a model comparison study
- Author
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D. R. Cameron, M. Van Oijen, C. Werner, K. Butterbach-Bahl, R. Grote, E. Haas, G. B. M. Heuvelink, R. Kiese, J. Kros, M. Kuhnert, A. Leip, G. J. Reinds, H. I. Reuter, M. J. Schelhaas, W. De Vries, and J. Yeluripati
- Subjects
Ecology ,QH540-549.5 ,Life ,QH501-531 ,Geology ,QE1-996.5 - Abstract
Forests are important components of the greenhouse gas balance of Europe. There is considerable uncertainty about how predicted changes to climate and nitrogen deposition will perturb the carbon and nitrogen cycles of European forests and thereby alter forest growth, carbon sequestration and N2O emission. The present study aimed to quantify the carbon and nitrogen balance, including the exchange of greenhouse gases, of European forests over the period 2010–2030, with a particular emphasis on the spatial variability of change. The analysis was carried out for two tree species: European beech and Scots pine. For this purpose, four different dynamic models were used: BASFOR, DailyDayCent, INTEGRATOR and Landscape-DNDC. These models span a range from semi-empirical to complex mechanistic. Comparison of these models allowed assessment of the extent to which model predictions depended on differences in model inputs and structure. We found a European average carbon sink of 0.160 ± 0.020 kgC m−2 yr−1 (pine) and 0.138 ± 0.062 kgC m−2 yr−1 (beech) and N2O source of 0.285 ± 0.125 kgN ha−1 yr−1 (pine) and 0.575 ± 0.105 kgN ha−1 yr−1 (beech). The European average greenhouse gas potential of the carbon sink was 18 (pine) and 8 (beech) times that of the N2O source. Carbon sequestration was larger in the trees than in the soil. Carbon sequestration and forest growth were largest in central Europe and lowest in northern Sweden and Finland, N. Poland and S. Spain. No single driver was found to dominate change across Europe. Forests were found to be most sensitive to change in environmental drivers where the drivers were limiting growth, where changes were particularly large or where changes acted in concert. The models disagreed as to which environmental changes were most significant for the geographical variation in forest growth and as to which tree species showed the largest rate of carbon sequestration. Pine and beech forests were found to have differing sensitivities to environmental change, in particular the response to changes in nitrogen and precipitation, with beech forest more vulnerable to drought. There was considerable uncertainty about the geographical location of N2O emissions. Two of the models BASFOR and LandscapeDNDC had largest emissions in central Europe where nitrogen deposition and soil nitrogen were largest, whereas the two other models identified different regions with large N2O emission. N2O emissions were found to be larger from beech than pine forests and were found to be particularly sensitive to forest growth.
- Published
- 2013
- Full Text
- View/download PDF
15. [Hemostaseologic study in the use of midazolam-ketamine]
- Author
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W, Heller, G, Fuhrer, M, Kuhner, U, Seiffer, and H, Vontin
- Subjects
Adult ,Male ,Benzodiazepines ,Hemostasis ,Adolescent ,Midazolam ,Hemodynamics ,Humans ,Anesthesia ,Female ,Ketamine ,Middle Aged ,Aged - Abstract
The combination of derivatives of benzodiazepine and analgetics is used now routinely in clinical situations. In former investigations we studied the effect of these drugs on substrates and enzymes of glycolysis and metabolism of lipids, whereby we focused our interest on changes of phosphofructokinase activity. The aim of this study was to monitor the influence of anaesthesia on parameters of haemostasis (Kallikrein-kinin-system, coagulation, fibrinolysis and several proteinase inhibitors). Therefore plasma samples of patients undergoing diagnostic endoscopy were analysed. For anaesthesia a combination of midazolam and ketamine was used.
- Published
- 1986
16. Satellite altimetry applications to geodesy, oceanography and geophysics
- Author
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A. G. Mourad, M. Kuhner, and S. Gopalapillai
- Subjects
Oceanography ,Satellite geodesy ,Satellite altimetry ,Geoid ,Puerto rican ,Geophysics ,Altimeter ,Geodesy ,Geology ,Sea level ,Gravity anomaly ,Remote sensing - Abstract
Satellite altimetry offers significant potential for many applications in geodesy and oceanography. The Skylab altimeter experiment was the first of a series (GEOS-C, 1975; SEASAT, 1978, 1980; etc.) planned by NASA for launch over the next decade. One goal of satellite altimetry is to determine the geoid (mean sea level) over the oceans to \pm 10 cm accuracy. Battelle's responsibility in the Skylab altimetry program is to develop a technique for calibration and evaluation of the altimetry data to determine the geoid. Although the Skylab altimeter instrument accuracy is about \pm 1 m, significant results have been obtained in identification of large geoidal features such as over the Puerto Rican trench. Comparison of the results of several passes appears to indicate that the altimeter is capable of sensing more details in geoid variations than are presently available from other techniques. Review of techniques developed for recovery of the gravity anomaly from satellite altimetry and the potential applications of results to oceanography, geodesy and geophysics are discussed.
- Published
- 1975
17. Ball State University faculty lecture series, 1976-1977
- Author
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Higgins, A. Stephen (Arthur Stephen); Ault, Frederick K. (Frederick Keith); Kruger, Terry L.; Sappenfield, Charles M.; Kuhner, Craig S.; Suput, Ray R.; Ward, Alan and Higgins, A. Stephen (Arthur Stephen); Ault, Frederick K. (Frederick Keith); Kruger, Terry L.; Sappenfield, Charles M.; Kuhner, Craig S.; Suput, Ray R.; Ward, Alan
- Abstract
The wonderful world of graduate education / A. Stephen Higgins -- Chemistry-- some surprising dimensions / Frederick K. Ault, Terry L. Kruger -- A hundred Hoosier houses : in progress / Charles M. Sappenfield, Craig S. Kuhner -- Academic libraries and faculty development / Ray R. Suput., This archival material has been provided for educational purposes. Ball State University Libraries recognizes that some historic items may include offensive content. Our statement regarding objectionable content is available at: https://dmr.bsu.edu/digital/about
- Published
- 1977
18. Hundred hoosier houses: in progress
- Author
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Sappenfield, Charles M.; Kuhner, Craig S.; Ward, Alan and Sappenfield, Charles M.; Kuhner, Craig S.; Ward, Alan
- Abstract
This archival material has been provided for educational purposes. Ball State University Libraries recognizes that some historic items may include offensive content. Our statement regarding objectionable content is available at: https://dmr.bsu.edu/digital/about
- Published
- 1976
19. Britton (K. G)—Les progrès de l'électronique
- Author
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M. Kuhner
- Subjects
Physics ,Electrical and Electronic Engineering ,Computer communication networks ,Humanities - Published
- 1952
20. Evaluating the accuracy and reliability of AI chatbots in disseminating the content of current resuscitation guidelines: a comparative analysis between the ERC 2021 guidelines and both ChatGPTs 3.5 and 4.
- Author
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Beck S, Kuhner M, Haar M, Daubmann A, Semmann M, and Kluge S
- Subjects
- Humans, Prospective Studies, Reproducibility of Results, Information Dissemination methods, Resuscitation standards, Artificial Intelligence, Practice Guidelines as Topic
- Abstract
Aim of the Study: Artificial intelligence (AI) chatbots are established as tools for answering medical questions worldwide. Healthcare trainees are increasingly using this cutting-edge technology, although its reliability and accuracy in the context of healthcare remain uncertain. This study evaluated the suitability of Chat-GPT versions 3.5 and 4 for healthcare professionals seeking up-to-date evidence and recommendations for resuscitation by comparing the key messages of the resuscitation guidelines, which methodically set the gold standard of current evidence and recommendations, with the statements of the AI chatbots on this topic., Methods: This prospective comparative content analysis was conducted between the 2021 European Resuscitation Council (ERC) guidelines and the responses of two freely available ChatGPT versions (ChatGPT-3.5 and the Bing version of the ChatGPT-4) to questions about the key messages of clinically relevant ERC guideline chapters for adults. (1) The content analysis was performed bidirectionally by independent raters. The completeness and actuality of the AI output were assessed by comparing the key message with the AI-generated statements. (2) The conformity of the AI output was evaluated by comparing the statements of the two ChatGPT versions with the content of the ERC guidelines., Results: In response to inquiries about the five chapters, ChatGPT-3.5 generated a total of 60 statements, whereas ChatGPT-4 produced 32 statements. ChatGPT-3.5 did not address 123 key messages, and ChatGPT-4 did not address 132 of the 172 key messages of the ERC guideline chapters. A total of 77% of the ChatGPT-3.5 statements and 84% of the ChatGPT-4 statements were fully in line with the ERC guidelines. The main reason for nonconformity was superficial and incorrect AI statements. The interrater reliability between the two raters, measured by Cohen's kappa, was greater for ChatGPT-4 (0.56 for completeness and 0.76 for conformity analysis) than for ChatGPT-3.5 (0.48 for completeness and 0.36 for conformity)., Conclusion: We advise healthcare professionals not to rely solely on the tested AI-based chatbots to keep up to date with the latest evidence, as the relevant texts for the task were not part of the training texts of the underlying LLMs, and the lack of conceptual understanding of AI carries a high risk of spreading misconceptions. Original publications should always be considered for comprehensive understanding., (© 2024. The Author(s).)
- Published
- 2024
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21. [Focus emergency medicine 2022/2023-Summary of selected studies in emergency medicine].
- Author
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Katzenschlager S, Obermaier M, Kuhner M, Spöttl W, Dietrich M, Weigand MA, Weilbacher F, and Popp E
- Subjects
- Emergency Service, Hospital, Emergency Medical Services, Emergency Medicine
- Published
- 2023
- Full Text
- View/download PDF
22. [Focus on emergency medicine 2021/2022-Summary of selected emergency medicine studies].
- Author
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Katzenschlager S, Obermaier M, Kuhner M, Spöttl W, Dietrich M, Weigand MA, Weilbacher F, and Popp E
- Subjects
- Emergency Service, Hospital, Emergency Medical Services, Emergency Medicine
- Published
- 2023
- Full Text
- View/download PDF
23. [Thrombotic occlusion of the extracorporeal circulation during hepatic chemosaturation despite targeted anticoagulation : A case report].
- Author
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Kuhner M, Tan B, Fiedler MO, Biecker O, Klein B, Chang DH, Weigand MA, and Dietrich M
- Subjects
- Humans, Melphalan therapeutic use, Extracorporeal Circulation, Anticoagulants therapeutic use, Liver Neoplasms drug therapy
- Abstract
Percutaneous hepatic chemosaturation is a treatment option for unresectable primary or secondary liver tumors. In this procedure the part of the inferior vena cava (VCI) that collects blood from the hepatic veins is isolated using a double balloon catheter. Like this, systemic distribution of the chemotherapeutic agent melphalan which is administered via the hepatic artery can be prevented. After passage through the liver and drainage from the retrohepatic VCI, the chemosaturated blood passes through two extracorporeal filters. Subsequently, the filtered blood is returned via the jugular vein. The procedure is often accompanied by severe hemodynamic instability, the cause of which is still not completely understood. In addition, coagulation management of extracorporeal circulation is often challenging. The authors report a case in which a thrombus formed in the returning leg of the extracorporeal circulation despite sufficient activated clotting time (ACT). Targeted problem search and resolution were necessary simultaneously to hemodynamic stabilization and interdisciplinary collaboration to successfully perform the intervention and provide the patient with safe treatment., (© 2022. The Author(s).)
- Published
- 2022
- Full Text
- View/download PDF
24. Disseminating resuscitation competences beyond traditional ERC-CPR courses: The ERC refresher seminars.
- Author
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Nikolaou NI, Bossaert L, Grünfeld M, Kuhner M, Silva R, and Greif R
- Subjects
- Adult, Female, Humans, Male, Middle Aged, Cardiopulmonary Resuscitation education, Curriculum standards, Education, Medical methods, Emergency Medicine education, Heart Arrest therapy
- Published
- 2019
- Full Text
- View/download PDF
25. Risk prediction in stable cardiovascular disease using a high-sensitivity cardiac troponin T single biomarker strategy compared to the ESC-SCORE.
- Author
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Biener M, Giannitsis E, Kuhner M, Zelniker T, Mueller-Hennessen M, Vafaie M, Stoyanov KM, Neumann FJ, Katus HA, Hochholzer W, and Valina CM
- Abstract
Objective: To evaluate the prognostic performance of high-sensitivity cardiac troponin T (hs-cTnT) compared with the ESC-SCORE., Methods: We included low-risk outpatients with stable cardiovascular (CV) disease categorised into need for non-secondary and secondary prevention. The prognostication of hs-cTnT at index visit was compared with the European Society of Cardiology-Systematic COronary Risk Evaluation (ESC-SCORE) with respect to all-cause mortality (ACM) and two composite endpoints (ACM, acute myocardial infarction (AMI) and stroke and ACM, AMI, stroke and rehospitalisation for acute coronary syndrome (ACS) and decompensated heart failure (DHF))., Results: Within a median follow-up of 796 days, a total of 16 deaths, 32 composite endpoints of ACM, AMI and stroke and 83 composite endpoints of ACM, AMI, stroke, rehospitalisation for ACS and DHF were observed among 693 stable low-risk outpatients. Using C-statistics, measurement of hs-cTnT alone outperformed the ESC-SCORE for the prediction of ACM in the entire study population (Δarea under the curve (AUC) 0.221, p=0.0039) and both prevention groups (non-secondary: ΔAUC 0.164, p=0.0208; secondary: ΔAUC 0.264, p=0.0134). For the prediction of all other secondary endpoints, hs-cTnT was at least as effective as the ESC-SCORE, both in secondary and non-secondary prevention. Using continuous and categorical net reclassification improvement and integrated discrimination improvement, hs-cTnT significantly improved reclassification regarding all endpoints in the entire population and in the secondary prevention cohort. In non-secondary prevention, hs-cTnT improved reclassification only for ACM. The results were confirmed in an independent external cohort on 2046 patients., Conclusions: Hs-cTnT is superior to the multivariable ESC-SCORE for the prediction of ACM and a composite endpoint in stable outpatients with and without relevant CV disease., Trial Registration Number: NCT01954303; Pre-results., Competing Interests: Competing interests: None declared.
- Published
- 2018
- Full Text
- View/download PDF
26. Prognostic Value of High-Sensitivity Cardiac Troponin T Compared with Risk Scores in Stable Cardiovascular Disease.
- Author
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Biener M, Giannitsis E, Kuhner M, Zelniker T, Mueller-Hennessen M, Vafaie M, Trenk D, Neumann FJ, Hochholzer W, and Katus HA
- Subjects
- Aged, Biomarkers blood, Cardiovascular Diseases mortality, Cardiovascular Diseases prevention & control, Cause of Death, Female, Heart Failure prevention & control, Humans, Male, Middle Aged, Myocardial Infarction prevention & control, Prognosis, Secondary Prevention, Sensitivity and Specificity, Stroke prevention & control, Cardiovascular Diseases diagnosis, Risk Assessment methods, Troponin T blood
- Abstract
Background: Risk stratification of patients with cardiovascular disease remains challenging despite consideration of risk scores., Methods: We aimed to evaluate the prognostic performance of high-sensitivity cardiac troponin T in a low-risk outpatient population presenting for nonsecondary and secondary prevention. All-cause mortality, a composite of all-cause mortality, acute myocardial infarction, and stroke (end point 2), and a composite of all-cause mortality, acute myocardial infarction, stroke and rehospitalization for acute coronary syndrome, and decompensated heart failure (end point 3) were defined. The prognostic performance of high-sensitivity cardiac troponin T on index visit was compared with the PROCAM score and 3 FRAMINGHAM subscores., Results: In 693 patients with a median follow-up of 796 days, we observed 16 deaths, 32 patients with end point 2, and 83 patients with end point 3. All risk scores performed better in the prediction of all-cause mortality in nonsecondary prevention (area under the curve [AUC]: PROCAM: 0.922 vs 0.523, P = .001, consistent for all other scores). In secondary prevention, high-sensitivity cardiac troponin T outperformed all risk scores in the prediction of all-cause mortality (ΔAUC: PROCAM: 0.319, P <.001, consistent for all other scores) and performed superiorly in the prediction of end point 2 compared with the PROCAM, FRAMINGHAM-Coronary Heart Disease, and FRAMINGHAM-Hard Coronary Heart Disease scores (ΔAUC: PROCAM: 0.176, P = .047, consistent for FRAMINGHAM-Coronary Heart Disease and FRAMINGHAM-Hard Coronary Heart Disease). In nonsecondary prevention, we observed a comparable prognostic performance of high-sensitivity cardiac troponin T and multivariable risk scores. Our findings on the prediction of all-cause mortality compared with the FRAMINGHAM-Hard Coronary Heart Disease score were confirmed in an independent validation cohort on 2046 patients., Conclusions: High-sensitivity troponin T provides excellent risk stratification regarding all-cause mortality and all-cause mortality, acute myocardial infarction, and stroke in a secondary prevention cohort in whom risk scores perform poorly., (Copyright © 2016 Elsevier Inc. All rights reserved.)
- Published
- 2017
- Full Text
- View/download PDF
27. Gene conversion in the evolution of both the H-2 and Qa class I genes of the murine major histocompatibility complex.
- Author
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Kuhner M, Watts S, Klitz W, Thomson G, and Goodenow RS
- Subjects
- Algorithms, Animals, Base Sequence, Cattle, Humans, Mice, Sequence Homology, Nucleic Acid, Biological Evolution, Gene Conversion, Genes, MHC Class I
- Abstract
In order to better understand the role of gene conversion in the evolution of the class I gene family of the major histocompatibility complex (MHC), we have used a computer algorithm to detect clustered sequence similarities among 24 class I DNA sequences from the H-2, Qa, and Tla regions of the murine MHC. Thirty-four statistically significant clusters were detected; individual analysis of the clusters suggested at least 25 past gene conversion or recombination events. These clusters are comparable in size to the conversions observed in the spontaneously occurring H-2Kbm and H-2Kkm2 mutations, and are distributed throughout all exons of the class I gene. Thus, gene conversion does not appear to be restricted to the regions of the class I gene encoding their antigen-presentation function. Moreover, both the highly polymorphic H-2 loci and the relatively monomorphic Qa and Tla loci appear to have participated as donors and recipients in conversion events. If gene conversion is not limited to the highly polymorphic loci of the MHC, then another factor, presumably natural selection, must be responsible for maintaining the observed differences in level of variation.
- Published
- 1990
- Full Text
- View/download PDF
28. [Hemostaseologic study in the use of midazolam-ketamine].
- Author
-
Heller W, Fuhrer G, Kuhner M, Seiffer U, and Vontin H
- Subjects
- Adolescent, Adult, Aged, Female, Humans, Male, Midazolam, Middle Aged, Anesthesia, Benzodiazepines, Hemodynamics drug effects, Hemostasis drug effects, Ketamine
- Abstract
The combination of derivatives of benzodiazepine and analgetics is used now routinely in clinical situations. In former investigations we studied the effect of these drugs on substrates and enzymes of glycolysis and metabolism of lipids, whereby we focused our interest on changes of phosphofructokinase activity. The aim of this study was to monitor the influence of anaesthesia on parameters of haemostasis (Kallikrein-kinin-system, coagulation, fibrinolysis and several proteinase inhibitors). Therefore plasma samples of patients undergoing diagnostic endoscopy were analysed. For anaesthesia a combination of midazolam and ketamine was used.
- Published
- 1986
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