Thermodynamik – grundlegende Einsichten für ein Verständnis von Umweltproblemen

In this paper, we present a way that allows to make fundamental statements about how economic action entails harmful effects on the environment. These effects are due to natural scientific reasons and are particularly present in the industrialised economy. The starting point of our considerations is that every economic action requires energy, of which many different forms exist. Taking all of these forms into account, heat energy has a particular significance, because other forms of energy can never appear in isolation, but only conjointly with heat energy. For this reason, the branch of physics that deals primarily with energy is called thermodynamics. The study of thermodynamics yields the central link between economic activity and its environmental impact. Understanding basic insights of thermodynamics enables decision-makers in environmental policy to understand the nature of environmental problems and to develop possible solutions. First, we deal with the connection between physical work and heat. Then we explain the two main Laws of Thermodynamics and go into detail about the concept of entropy. We use Boltzmann's approach of the degree of order to give an illustration of the entropy concept. We then turn to the consideration of thermodynamics in economics, first provided by Georgescu-Roegen in 1971. Following this we explain the importance of thermodynamics for environmental policy. We conclude with a summary. In diesem Beitrag stellen wir einen Weg vor, der es erlaubt, grundsätzliche Aussagen darüber zu treffen, dass wirtschaftliches Handeln schädliche Auswirkungen auf die Umwelt mit sich bringt. Diese Auswirkungen sind naturwissenschaftlich bedingt und treten insbesondere in der industrialisierten Wirtschaft auf. Ausgangspunkt unserer Überlegungen ist, dass jedes wirtschaftliche Handeln Energie benötigt, von der es viele verschiedene Formen gibt. Unter Berücksichtigung all dieser Formen kommt der Wärmeenergie eine besondere Bedeutung zu, da andere Energieformen nie isoliert, sondern nur in Verbindung mit der Wärmeenergie auftreten können. Aus diesem Grund wird der Zweig der Physik, der sich hauptsächlich mit Energie beschäftigt, Thermodynamik genannt. Das Studium der Thermodynamik stellt die zentrale Verbindung zwischen wirtschaftlicher Tätigkeit und ihren Auswirkungen auf die Umwelt her. Das Verständnis grundlegender Erkenntnisse der Thermodynamik ermöglicht es Entscheidungsträgern in der Umweltpolitik, das Entstehen von Umweltproblemen zu verstehen und mögliche Lösungen zu entwickeln. Zunächst befassen wir uns mit dem Zusammenhang zwischen physikalischer Arbeit und Wärme. Dann erläutern wir die beiden Hauptsätze der Thermodynamik und gehen ausführlich auf das Konzept der Entropie ein. Zur Veranschaulichung des Entropiekonzepts verwenden wir den Boltzmann'schen Ansatz des Ordnungsgrades. Anschließend wenden wir uns der Betrachtung der Thermodynamik in den Wirtschaftswissenschaften zu, die erstmals von Georgescu-Roegen im Jahr 1971 vorgelegt wurde. Anschließend erläutern wir die Bedeutung der Thermodynamik für die Umweltpolitik. Wir schließen mit einer Zusammenfassung

Decreased Left Ventricular Torsion and Untwisting in Children with Dilated Cardiomyopathy

The purpose of this study was to analyze left ventricular (LV) torsion and untwisting, and to evaluate the correlation between torsion and other components of LV contraction in children with dilated cardiomyopathy (DCM). Segmental and global rotation, rotational rate (Vrot) were measured at three levels of LV using the two-dimensional (2D) speckle tracking imaging (STI) method in 10 DCM patients (range 0.6-15 yr, median 6.5 yr, 3 females) and 17 age- and sex-matched normal controls. Global torsion was decreased in DCM (peak global torsion; 10.9±4.6° vs. 0.3±2.1°, p<0.001). Loss of LV torsion occurred mainly by the diminution of counterclockwise apical rotation and was augmented by somewhat less reduction in clockwise basal rotation. In DCM, the normal counterclockwise apical rotation was not observed, and the apical rotation about the central axis was clockwise or slightly counterclockwise (peak apical rotation; 5.9±4.1° vs. -0.9±3.1°, p<0.001). Systolic counterclockwise Vrot and early diastolic clockwise Vrot at the apical level were decreased or abolished. In DCM, decreased systolic torsion and loss of early diastolic recoil contribute to LV systolic and diastolic dysfunction. The STI method may facilitate the serial evaluation of the LV torsional behavior in clinical settings and give new biomechanical concepts for better management of patients with DCM

Effects of Once-Weekly Exenatide on Cardiovascular Outcomes in Type 2 Diabetes.

Abstract BACKGROUND: The cardiovascular effects of adding once-weekly treatment with exenatide to usual care in patients with type 2 diabetes are unknown. METHODS: We randomly assigned patients with type 2 diabetes, with or without previous cardiovascular disease, to receive subcutaneous injections of extended-release exenatide at a dose of 2 mg or matching placebo once weekly. The primary composite outcome was the first occurrence of death from cardiovascular causes, nonfatal myocardial infarction, or nonfatal stroke. The coprimary hypotheses were that exenatide, administered once weekly, would be noninferior to placebo with respect to safety and superior to placebo with respect to efficacy. RESULTS: In all, 14,752 patients (of whom 10,782 [73.1%] had previous cardiovascular disease) were followed for a median of 3.2 years (interquartile range, 2.2 to 4.4). A primary composite outcome event occurred in 839 of 7356 patients (11.4%; 3.7 events per 100 person-years) in the exenatide group and in 905 of 7396 patients (12.2%; 4.0 events per 100 person-years) in the placebo group (hazard ratio, 0.91; 95% confidence interval [CI], 0.83 to 1.00), with the intention-to-treat analysis indicating that exenatide, administered once weekly, was noninferior to placebo with respect to safety (P<0.001 for noninferiority) but was not superior to placebo with respect to efficacy (P=0.06 for superiority). The rates of death from cardiovascular causes, fatal or nonfatal myocardial infarction, fatal or nonfatal stroke, hospitalization for heart failure, and hospitalization for acute coronary syndrome, and the incidence of acute pancreatitis, pancreatic cancer, medullary thyroid carcinoma, and serious adverse events did not differ significantly between the two groups. CONCLUSIONS: Among patients with type 2 diabetes with or without previous cardiovascular disease, the incidence of major adverse cardiovascular events did not differ significantly between patients who received exenatide and those who received placebo. (Funded by Amylin Pharmaceuticals; EXSCEL ClinicalTrials.gov number, NCT01144338 .)

Assessing the life-cycle sustainability of algae and bacteria-based wastewater treatment systems: High-rate algae pond and sequencing batch reactor

High Rate Algae Ponds (HRAPs) are a promising technology for the treatment of municipal wastewater in locations with sufficient space and solar radiation. Algae-based processes do not require aeration, and thus have the potential to be less energy-intensive than activated sludge processes. We used a combination of LCA and LCCA analysis to evaluate the sustainability of HRAP systems, using data from the construction and operation of two demonstration-scale systems in Almería and Cádiz, Spain. As a reference for comparison, we used data from an activated sludge-based Sequencing Batch Reactor (SBR) treatment system in operation in Leppersdorf, Germany, which has comparable removal rates for a similar inflow. We focused solely on the actual wastewater treatment aspect of these technologies, excluding sludge treatment from this analysis. Based on our analysis, the current HRAP technology is more energy-efficient than activated sludge-based SBRs and requires only 22% of its electricity consumption. In addition, HRAP is more advantageous both economically (0.18 €/m3 versus 0.26 €/m3) and environmentally, with both lower global warming and eutrophication potentials (146.27 vs. 458.27 × 10−3 kg CO2 equiv./m3; 126.14 vs. 158.01 × 10−6 kg PO4 equiv./m3). However, the Net Environmental Benefit of SBR was slightly more favorable than of HRAP because of the higher removal rate for nutrients of SBR.</p

Assessing the life-cycle sustainability of algae and bacteria-based wastewater treatment systems: High-rate algae pond and sequencing batch reactor

High Rate Algae Ponds (HRAPs) are a promising technology for the treatment of municipal wastewater in locations with sufficient space and solar radiation. Algae-based processes do not require aeration, and thus have the potential to be less energy-intensive than activated sludge processes. We used a combination of LCA and LCCA analysis to evaluate the sustainability of HRAP systems, using data from the construction and operation of two demonstration-scale systems in Almería and Cádiz, Spain. As a reference for comparison, we used data from an activated sludge-based Sequencing Batch Reactor (SBR) treatment system in operation in Leppersdorf, Germany, which has comparable removal rates for a similar inflow. We focused solely on the actual wastewater treatment aspect of these technologies, excluding sludge treatment from this analysis. Based on our analysis, the current HRAP technology is more energy-efficient than activated sludge-based SBRs and requires only 22% of its electricity consumption. In addition, HRAP is more advantageous both economically (0.18 €/m3 versus 0.26 €/m3) and environmentally, with both lower global warming and eutrophication potentials (146.27 vs. 458.27 × 10−3 kg CO2 equiv./m3; 126.14 vs. 158.01 × 10−6 kg PO4 equiv./m3). However, the Net Environmental Benefit of SBR was slightly more favorable than of HRAP because of the higher removal rate for nutrients of SBR.Accepted Author ManuscriptEnvironmental Technology and DesignBT/Environmental Biotechnolog