High-sensitivity cardiac troponin T and copeptin assays to improve diagnostic accuracy of exercise stress test in patients with suspected coronary artery disease

Background: The average diagnostic sensitivity of exercise stress tests (ESTs) is lower than that of other non-invasive cardiac stress tests. The aim of the study was to examine whether high-sensitivity cardiac troponin T (hs-cTnT) or copeptin concentrations rise in response to inducible myocardial ischaemia and may improve the diagnostic accuracy of ESTs. Methods and results: An EST was performed stepwise on a bicycle ergometer by 383 consecutive patients with suspected or progression of coronary artery disease (CAD). In addition venous blood samples for measurement of hs-cTnT and copeptin were collected prior to EST, at peak exercise, and 4 h after EST. Coronary angiography was assessed for all patients. Patients with significant CAD (n=224) were more likely to be male and older compared to patients with non-significant CAD (n=169). Positive EST was documented in 125 (55.8%) patients with significant CAD and in 69 (43.4%) patients with non-significant CAD. Copeptin and hs-cTnT concentrations at baseline were higher in patients with significant CAD (copeptin: 10.8 pmol/l (interquartile range (IQR) 8.1–15.6) vs 9.4 pmol/l (IQR 7.1–13.9); p=0.04; hs-cTnT: 3.0 ng/l (IQR <3.0–5.4) vs <3.0 ng/l (IQR <3.0); p=0.006). Hs-cTnT improved sensitivity (61.6% vs 55.8%), specificity (67.7% vs 56.6%) and the positive predictive value (PPV) (72.3% vs 64.4%) and negative (55.2% vs 47.6%) predictive value (NPV) of EST. Copeptin could not improve sensitivity (55.4% vs 55.8%) and reduced specificity, PPV and NPV. Conclusions: The measurement of hs-cTnT during EST improves sensitivity, specificity, and positive and negative predictive values. In contrast, measurement of copeptin does not improve diagnostic sensitivity and reduces specificity

Biogas production from sugarcane waste: assessment on kinetic challenges for process designing

Biogas production from sugarcane waste has large potential for energy generation, however, to enable the optimization of the anaerobic digestion (AD) process each substrate characteristic should be carefully evaluated. In this study, the kinetic challenges for biogas production from different types of sugarcane waste were assessed. Samples of vinasse, filter cake, bagasse, and straw were analyzed in terms of total and volatile solids, chemical oxygen demand, macronutrients, trace elements, and nutritional value. Biochemical methane potential assays were performed to evaluate the energy potential of the substrates according to different types of sugarcane plants. Methane yields varied considerably (5–181 Nm3·tonFM−1), mainly due to the different substrate characteristics and sugar and/or ethanol production processes. Therefore, for the optimization of AD on a large-scale, continuous stirred-tank reactor with long hydraulic retention times (>35 days) should be used for biogas production from bagasse and straw, coupled with pre-treatment process to enhance the degradation of the fibrous carbohydrates. Biomass immobilization systems are recommended in case vinasse is used as substrate, due to its low solid content, while filter cake could complement the biogas production from vinasse during the sugarcane offseason, providing a higher utilization of the biogas system during the entire year

Radon (222Rn) as tracer for submarine groundwater discharge investigation—limitations of the approach at shallow wind‐exposed coastal settings

Mapping radon (222Rn) distribution pat- terns in the coastal sea is a widely applied method for localizing and quantifying submarine groundwater discharge (SGD). While the literature reports a wide range of successful case studies, methodical problems that might occur in shallow wind-exposed coastal settings are generally neglected. This paper evalu- ates causes and effects that resulted in a failure of the radon approach at a distinct shallow wind-exposed location in the Baltic Sea. Based on a simple radon mass balance model, we discuss the effect of both wind speed and wind direction as causal for this fail- ure. We show that at coastal settings, which are domi- nated by gentle submarine slopes and shallow waters, both parameters have severe impact on coastal radon distribution patterns, thus impeding their use for SGD investigation. In such cases, the radon approach needs necessarily to allow for the impact of wind speed and wind direction not only during but also prior to the field campaign

Radon (222Rn) as Tracer for Submarine Groundwater Discharge Investigation—Limitations of the Approach at Shallow Wind-Exposed Coastal Settings

Mapping radon (222Rn) distribution patterns in the coastal sea is a widely applied method for localizing and quantifying submarine groundwater discharge (SGD). While the literature reports a wide range of successful case studies, methodical problems that might occur in shallow wind-exposed coastal settings are generally neglected. This paper evaluates causes and effects that resulted in a failure of the radon approach at a distinct shallow wind-exposed location in the Baltic Sea. Based on a simple radon mass balance model, we discuss the effect of both wind speed and wind direction as causal for this failure. We show that at coastal settings, which are dominated by gentle submarine slopes and shallow waters, both parameters have severe impact on coastal radon distribution patterns, thus impeding their use for SGD investigation. In such cases, the radon approach needs necessarily to allow for the impact of wind speed and wind direction not only during but also prior to the field campaign

Kinetics of Olivine Weathering in Seawater: An Experimental Study

Enhanced weathering of mafic and ultra-mafic minerals has been suggested as a strategy for carbon dioxide removal (CDR) and a contribution to achieve a balance between global CO2 sources and sinks (net zero emission). This study was designed to assess CDR by dissolution of ultramafic sand (UMS) in artificial seawater (ASW). Fine grained UMS with an olivine content of ~75% was reacted in ASW for up to 134 days at 1 bar and 21.5–23.9°C. A decline in total alkalinity (TA) was observed over the course of the experiments. This unexpected result indicates that TA removal via precipitation of cation-rich authigenic phases exceeded the production of TA induced by olivine dissolution. The TA decline was accompanied by a decrease in dissolved inorganic carbon and Ca concentrations presumably induced by CaCO3 precipitation. Temporal changes in dissolved Si, Ca, Mg, and TA concentrations observed during the experiments were evaluated by a numerical model to identify secondary mineral phases and quantify rates of authigenic phase formation. The modeling indicates that CaCO3, FeOOH and a range of Mg-Si-phases were precipitated during the experiments. Chemical analysis of precipitates and reacted UMS surfaces confirmed that these authigenic phases accumulated in the batch reactors. Nickel released during olivine dissolution, a potential toxic element for certain organisms, was incorporated in the secondary phases and is thus not a suitable proxy for dissolution rates as proposed by earlier studies. The overall reaction stoichiometry derived from lab experiments was applied in a box model simulating atmospheric CO2 uptake in a continental shelf setting induced by olivine addition. The model results indicate that CO2 uptake is reduced by a factor of 5 due to secondary mineral formation and the buffering capacity of seawater. In comparable natural settings, olivine addition may thus be a less efficient CDR method than previously believed

Incremental value of high-sensitive troponin T in addition to the revised cardiac index for peri-operative risk stratification in non-cardiac surgery

Aims We aimed to evaluate the incremental value of high-sensitive troponin T (hsTnT) for risk prediction prior to non-cardiac surgery in comparison with the established revised cardiac index. Methods and results In this prospective, international multicentre observational study, 979 patients prior to non-cardiac surgery were enrolled. The endpoints were in-hospital mortality, the combination of death, acute myocardial infarction, cardiac arrest, cardio-pulmonary resuscitation, and acute decompensated heart failure. Twenty-five patients (2.6%) deceased and 36 (3.7%) of the patients experienced the combined endpoint. Cardiac markers were elevated in those patients who died when compared with survivors (hsTnT: 21 ng/L vs. 7 ng/L; P < 0.001; NT-proBNP: 576 pg/mL vs. 166 pg/mL; P < 0.001). Applying a cut-off for hsTnT of 14 ng/L and for NT-proBNP of 300 pg/mL, those patients with elevated hsTnT had a mortality of 6.9 vs. 1.2% (P < 0.001) and with elevated NT-proBNP 4.8 vs. 1.4% (P = 0.002). The highest AUC of the ROC curve was found for hsTnT as a predictor for mortality of 0.809. In a multivariate Cox regression analyses, hsTnT was the strongest independent predictor for the combined endpoint [HR 2.6 (95% CI: 1.3-5.3); P = 0.01]. Conclusion High-sensitive troponin T provides strong prognostic information in patients undergoing non-cardiac surgery incremental to the widely accepted revised cardiac inde

Auswirkungen der gegenwärtig diskutierten Novellierungsvorschläge für das EEG-2014: Hintergrundpapier – überarbeitet am 31.03.2014

Mit der geplanten Novellierung im Sommer 2014 läuft die Politik Gefahr, den moderaten Ausbau der Stromerzeugung aus Biomasse weitgehend zu beenden. Für die in den letzten Jahren so erfolgreich etablierten Technologielinien besteht das Risiko eines kompletten Ausbau- und damit auch Entwicklungsstopps. Für den bereits existierenden umfangreichen Anlagenbestand zeigt der aktuelle Entwurf keine Perspektive auf und setzt die bisher geleistete Entwicklung aufs Spiel. Auf diesen Sachverhalt wurde bereits von 65 Forschungsnehmern des Förderprogrammes Energetische Biomassenutzung des BMUB hingewiesen. Das vorliegende Hintergrundpapier spricht die Schwachpunkte der geplanten Novellierung an, skizziert deren Auswirkungen und gibt Empfehlungen zur Anpassung der gegenwärtig vorliegenden Vorschläge

Costs of Measuring Outcomes of Acute Hospital Care in a Longitudinal Outcomes Measurement System

It is widely acknowledged that the measurement of outcomes of care and the comparison of outcomes over time within health care providers and risk-adjusted comparisons among providers are important parts of improving quality and cost-effectiveness of care. However, few studies have assessed the costs of measuring outcomes of care. We sought to evaluate the personnel and financial resources spent for a prospective assessment of outcomes of acute hospital care by health professionals in internal medicine. The study included 15 primary care hospitals participating in a longitudinal outcomes measurement program and 2005 patients over an assessment period with an average duration of 6 months. Each hospital project manager participated in a previously-tested structured 30-minute telephone interview. Outcome measures include time spent by the individual job titles in implementing and running the outcomes measurement program. Job-title-specific times were used to calculate costs from the hospitals' perspective. One-time costs (C2132 + 1352) and administrative costs (95 97 per week) varied substantially. Costs per patient were fairly stable at around 20. We estimated that the total cost for each hospital to assess outcomes of care for accreditation (10 tracer diagnoses over 6 months) would be 9700 and that continuous monitoring of outcomes (5 tracer diagnoses) would cost 12,400 per year. This study suggests that outcomes of acute hospital care can be assessed with limited resources and that standardized training programs would reduce variability in overall costs. This study should help hospital decision makers to estimate the necessary funding for outcomes measurement initiatives

Stellungnahme zum EEG 2017

Mit dem EEG 2017 wurde die zukünftige Förderung von Biomasseanlagen, zusammen mit Photovoltaikund Windkraftanlagen, auf ein Ausschreibungsverfahren umgestellt. Im Gegensatz zu Wind- und Photovoltaik-Anlagen, können sich bei der Förderung der Stromerzeugung aus Biomasse jedoch auch Bestandsanlagen für einen zweiten Förderzeitraum bewerben. Um einen Förderanspruch für weitere 10 Jahre zu erwerben, müssen die Anlagen verschiedenste Voraussetzungen erfüllen. Dazu gehören unter anderem Vorgaben zur Flexibilisierung und zum Substrateinsatz in Biogasanlagen (sinkender Maisdeckel). Im September 2017 wurde die erste Ausschreibungsrunde für Bioenergieanlagen durchgeführt. Unter anderem aufgrund der langen durchschnittlichen Vergütungs-Restlaufzeit der meisten Bioenergieanlagen war das Interesse noch verhalten. Das Ausschreibungsvolumen betrug ca. 122 MWel installierte Leistung. Von 33 Geboten mit einem Volumen von rund 41 MWel erhielten 24 Gebote mit einem Volumen von rund 28 MWel einen Zuschlag. Obwohl das Volumen in der ersten Ausschreibungsrunde nicht ausgeschöpft wurde, lassen sich aus den ersten Erfahrungen bereits Änderungsvorschläge zur Verbesserung des Ausschreibungsdesigns ableiten. Ziel sollte sein, den Wettbewerb innerhalb der Ausschreibungen für Biomasseanlagen zu erhöhen und Perspektiven für die Entwicklung des Anlagenbestandes aufzuzeigen. Die Änderungsvorschläge werden nachfolgend kurz dargestellt