Economics of long-term portfolio management in electricity markets

Weltweit erfordern Erneuerungen und Erweiterungen der Stromversorgungssysteme hohe Investitionen in neue Stromerzeugungsanlagen. Die hierfür erforderlichen Kraftwerksinvestitionen bergen aufgrund der hohen Baukosten und der langen Lebensdauern zwischen 20 und 50 Jahren erhebliche finanzielle Risiken sowohl für einzelne Investoren als auch für die Wettbewerbsfähigkeit ganzer Volkswirtschaften; denn der von Energiepolitikern gesetzte regulatorische Marktrahmen und im Markt getroffenen Investitionsentscheidungen von heute beeinflussen die volkswirtschaftlichen Kosten für die Energieversorgung von morgen. Daher sollten Energiepolitiker bei der Förderung bestimmter Kraftwerkstechnologien und Investoren bei ihren Entscheidungen zu Kraftwerksneubauten sowohl die Kosten (bzw. Renditen) als auch die finanziellen Risiken im Hinblick auf das Erzeugungsportfolio im Markt berücksichtigen. Diese Arbeit zielt darauf ab, die Entscheidungstheorie unter Unsicherheit im Hinblick auf Kraftwerksinvestitionen weiterzuentwickeln und effiziente Erzeugungsportfolios sowohl von einer volkswirtschaftlichen als auch von einer Investoren-Perspektive zu erforschen. Dazu setzt diese Arbeit auf den in der Literatur bereits intensiv diskutierten Konzepten zur Kapazitätsplanung sowie des "Peak-load Pricing" einerseits sowie der Markowitz'schen Portfoliotheorie andererseits auf und entwickelt diese in einem integrierten Modellansatz weiter. Dabei stehen finanzielle Risiken aus den spezifischen Brennstoffpreis-Unsicherheiten unterschiedlicher Erzeugungs-Technologien im Fokus dieser Arbeit. Nach einer kurzen Zusammenfassung elementarer Grundlagen zur Entscheidungstheorie wird die Investitionsentscheidung als ein formales Optimierungsproblem modelliert. Hiervon werden quantitative Kriterien zur Diversifikation des Erzeugungsportfolios in Abhängigkeit von der Risikoaversion abgeleitet und analytische Lösungen für bezogen auf Kosten und Risiken effiziente Erzeugungsportfolios aus einer Wohlfahrtperspektive bestimmt. Die Ergebnisse belegen, dass Diversifikation per se selbst bei hoher gesellschaftlicher Risikoaversion nicht zwingend vorteilhaft ist. Der effiziente Technologiemix im Erzeugungsportfolio ist vielmehr durch die spezifischen Risiken der einzelnen Technologien selbst bestimmt. Folglich werden mit steigender gesellschaftlicher Risikoaversion jene Erzeugungstechnologien mit geringen Brennstoffpreisrisiken (beispielsweise Kernkraft oder Braunkohle) gegenüber Technologien mit hohen Preisschwankungen (beispielsweise Gas) bevorzugt. Im Gegensatz zu bestehenden Forschungsarbeiten, in denen Veränderungen der Grenzpreis basierten Angebotskurve ("Merit Order") aufgrund von Schwankungen in den Brennstoffkosten nicht betrachtet werden, wird dieses Risiko in der vorliegenden Arbeit explizit analysiert und quantifiziert. Im Ergebnis wird gezeigt, dass Merit Order Risiken insbesondere bei langen Investitionszeiträumen den Technologiemix in effizienten Erzeugungsportfolios erheblich beeinflussen. Während bestehende Literatur zum Thema Kapazitätsplanung und Portfoliotheorie gemeinhin die Annahme vollkommener Märkte voraussetzt, wird in dieser Arbeit analytisch gezeigt, wie Risikoaversion von Investoren die sich im Marktgleichgewicht einstellende Struktur des Erzeugungsportfolios beeinflussen und zu erheblichen Abweichungen vom wohlfahrtsoptimalen Technologiemix führen kann. Schließlich wird wieder aus der Investorenperspekive empirisch der Einfluss des Technologiemixes im Erzeugungsportfolio auf die erwartete Rendite von großen europäischen Energieversorgern untersucht. Es kann gezeigt werden, dass die Erzeugungsstruktur einen signifikanten Einfluss auf die historischen Aktienrenditen der untersuchten Unternehmen hat. Die Ergebnisse liefern einen theoretischen und praktischen Beitrag zur Ermittlung risikoadjustierter Kapitalkosten für typische Erzeugungstechnologien aus einer Investorenperspektive.Electricity systems around the world are facing massive investments to replace aged and add new generation capacity. Thereby, investments in power generation assets bear considerable financial risks in view of the typically high capital investments and long-lasting asset lifetimes between 20 and 50 years. The regulatory frame set by policy makers and the investment decisions of companies of today influence the socioeconomic costs of tomorrow in liberalized electricity markets. Thus, both policy makers and investors should reflect costs (respectively return) and monetary risks of their investment decisions carefully to build economical and long-term sustainable electricity systems. This thesis aims to contribute to the theory of decision making under uncertainty in the field of electricity generation investments and to analyze efficient generation portfolios both from a societal and from a company perspective. For that, the research proposed in this thesis combines and extends concepts of capacity planning and peak load pricing on the one hand and Mean-Variance Portfolio theory based on Markowitz on the other hand—which are well-discussed in economic literature individually—in an integrated modelling approach. Thereby, the research in this thesis is focused on financial risks induced by technology-specific fuel price uncertainties which are inherent to all non-renewable generation technologies. Having briefly recaped the fundamentals of decision theory under uncertainty, we propose a model that captures the investment decision as a formal optimization problem. From the latter, quantitative diversification criteria are derived and analytical solutions for cost-risk efficient generation portfolios are determined from a welfare perspective. The results show that diversification of generation portfolios is—even under high societal risk aversion—not beneficial per-se. The technology mix in efficient portfolios depends rather on the specific risk of each technology. Consequently, generation technologies with traditionally low fuel price fluctuations (e.g. nuclear or lignite plants) are preferred compared with technologies with higher price fluctuations (e.g. gas) with increasing societal risk aversion. While commonly neglected in literature, the effect of reversal risks in the short-term order of dispatch ("merit order") is analytically studied and quantified in this thesis. It is shown that this risk factor can impact the efficient technology mix substantially especially given long-term investment horizons. While existing literature in the field of capacity planning and Mean-Variance Theory relies predominantly on the key assumptions of perfect markets, we show how risk-averse investor behavior may shift the technology structure in the market equilibrium significantly away from the welfare optimum. Finally, we resume the focus on the investor perspective and empirically study the impact of the fuel mix structure in power generation portfolios on expected stock returns for major European power companies. It is shown that the generation fuel mix has a significant impact on the historical stock returns of the investigated companies. Thus, these results provide theoretical and practical benefit to determine adequate riskadjusted capital costs for typical generation technologies from an investor perspective

Site of Blood Vessel Damage and Relevance of CD18 in a Murine Model of Immune Complex-Mediated Vasculitis

How neutrophils (polymorphonuclear neutrophils, PMNs) damage vessels in leukocytoclastic vasculitis (LcV) mediated by immune complexes (ICs) is unclear. If degradative enzymes and oxygen radicals are released from PMNs while adhering to the inner side of the vessel wall, they could be washed away by the blood stream or neutralized by serum protease inhibitors. We investigated if in LcV PMNs could damage vessels from the tissue side after transmigration. We used CD18-deficient (CD18−/−) mice because the absence of CD18 excludes transmigration of PMNs. When eliciting the Arthus reaction in ears of CD18−/− mice, deposition of ICs was not sufficient to recruit PMNs or to induce IC-mediated LcV. Injection of PMNs intradermally in CD18−/− mice allowed us to investigate if bypassing diapedesis and placing PMNs exclusively on the abluminal side leads to vascular destruction. We found that injected PMNs gathered around perivascular ICs, but did not cause vessel damage. Only intravenous injection of wild-type PMNs could re-establish the Arthus reaction in CD18−/− mice. Thus, PMNs cause vessel damage during diapedesis from the luminal side, but not from the perivascular space. We suggest that in order to shield the cytotoxic products from the blood stream, ICs induce particularly tight interactions between them, PMNs and endothelial cells

S1 guideline: Differential diagnosis of acute and chronic redness of the lower legs

Acute or chronic redness of the lower leg is a frequent reason for visits to clinics and practices. The differential diagnosis is often challenging. The aim of this guideline is to define criteria and procedures for the differential diagnosis of acute or chronic, unilateral or bilateral redness of the lower leg. Finding the correct diagnosis is essential for selecting an appropriate treatment and can help to reduce the inappropriate use of antibiotics. The guideline committee identified the most relevant differential diagnoses: 1. erysipelas, 2. stasis dermatitis, 3. hyperergic ictus reaction, 4. superficial and deep vein thrombosis, 5. gout, 6. chronic allergic contact dermatitis, and 7. acute toxic or allergic contact dermatitis. Algorithms/diagnostic pathways, each of which can be broken down into anamnesis, clinical examination, and diagnostics, have been developed for these seven diagnoses. In addition, the guideline group identified over 40 other relevant diagnoses and summarized their characteristics in a table to facilitate further differential diagnoses

Interleukin 1α Promotes Th1 Differentiation and Inhibits Disease Progression in Leishmania major–susceptible BALB/c Mice

Protective immunity against pathogens such as Leishmania major is mediated by interleukin (IL)-12–dependent Th1-immunity. We have shown previously that skin-dendritic cells (DCs) from both resistant C57BL/6 and susceptible BALB/c mice release IL-12 when infected with L. major, and infected BALB/c DCs effectively vaccinate against leishmaniasis. To determine if cytokines other than IL-12 might influence disease outcome, we surveyed DCs from both strains for production of a variety of cytokines. Skin-DCs produced significantly less IL-1α in response to lipopolysaccharide/interferon γ or L. major when expanded from BALB/c as compared with C57BL/6 mice. In addition, IL-1α mRNA accumulation in lymph nodes of L. major–infected BALB/c mice was ∼3-fold lower than that in C57BL/6 mice. Local injections of IL-1α during the first 3 d after infection led to dramatic, persistent reductions in lesion sizes. In L. major–infected BALB/c mice, IL-1α administration resulted in increased Th1- and strikingly decreased Th2-cytokine production. IL-1α and IL-12 treatments were similarly effective, and IL-1α efficacy was strictly IL-12 dependent. These data indicate that transient local administration of IL-1α acts in conjunction with IL-12 to influence Th-development in cutaneous leishmaniasis and prevents disease progression in susceptible BALB/c mice, perhaps by enhancing DC-induced Th1-education. Differential production of IL-1 by C57BL/6 and BALB/c mice may provide a partial explanation for the disparate outcomes of infection in these mouse strains

S2k guidelines for the diagnosis and treatment of herpes zoster and postherpetic neuralgia

The present guidelines are aimed at residents and board-certified specialists in the fields of dermatology, ophthalmology, ENT, pediatrics, neurology, virology, infectious diseases, anesthesiology, general medicine and any other medical specialties involved in the management of patients with herpes zoster. They are also intended as a guide for policymakers and health insurance funds. The guidelines were developed by dermatologists, virologists, ophthalmologists, ENT physicians, neurologists, pediatricians and anesthesiologists/pain specialists using a formal consensus process (S2k). Readers are provided with an overview of the clinical and molecular diagnostic workup, including antigen detection, antibody tests and viral culture. Special diagnostic situations and complicated disease courses are discussed. The authors address general and special aspects of antiviral therapy for herpes zoster and postherpetic neuralgia. Furthermore, the guidelines provide detailed information on pain management including a schematic overview, and they conclude with a discussion of topical treatment options

Predictive Role Of Body Composition Parameters In Operable Breast Cancer Patients Treated With Neoadjuvant Chemotherapy.

BACKGROUND: Fat tissue is strongly involved in BC tumorigenesis inducing insulin resistance, chronic inflammation and hormonal changes. Computed tomography (CT) imaging instead of body mass index (BMI) gives a reliable measure of skeletal muscle mass and body fat distribution. The impact of body composition parameters (BCPs) on chemosensitivity is still debated. We examined the associations between BCPs and tumor response to neoadjuvant chemotherapy (NC) in patients treated for operable breast cancer (BC). METHODS: A retrospective review of BC patients treated with NC in Modena Cancer Center between 2005 and 2017 was performed. BCPs, such as subcutaneous fat area (SFA), visceral fat area (VFA), lumbar skeletal muscle index (LSMI) and liver-to-spleen (L/S) ratio were calculated by Advance workstation (General Electric), software ADW server 3.2 or 4.7. BMI and BCPs were correlated with pathological complete response (pCR) and survival outcomes. RESULTS: 407 patients were included in the study: 55% with BMI < 25 and 45% with BMI 65 25. 137 of them had pre-treatment CT scan imagines. Overweight was significantly associated with postmenopausal status and older age. Hormonal receptor positive BC was more frequent in overweight patients (p<0.05). Postmenopausal women had higher VFA, fatty liver disease and obesity compared to premenopausal patients. No association between BMI classes and tumor response was detected. High VFA and liver steatosis were negative predictive factors for pCR (pCR rate: 36% normal VFA vs 20% high VFA, p= 0.048; no steatosis 32% vs steatosis 13%, p=0.056). Neither BMI classes nor BCPs significantly influenced overall survival and relapse-free survival. CONCLUSION: Visceral adiposity as well as steatosis were closely involved in chemosensitivity in BC patients treated with NC. Their measures from clinically acquired CT scans provide significant predictive information that outperform BMI value. More research is required to evaluate the relationship among adiposity site and survival outcomes

Bacteria tracking by in vivo magnetic resonance imaging

Background: Different non-invasive real-time imaging techniques have been developed over the last decades to study bacterial pathogenic mechanisms in mouse models by following infections over a time course. In vivo investigations of bacterial infections previously relied mostly on bioluminescence imaging (BLI), which is able to localize metabolically active bacteria, but provides no data on the status of the involved organs in the infected host organism. In this study we established an in vivo imaging platform by magnetic resonance imaging (MRI) for tracking bacteria in mouse models of infection to study infection biology of clinically relevant bacteria. Results: We have developed a method to label Gram-positive and Gram-negative bacteria with iron oxide nano particles and detected and pursued these with MRI. The key step for successful labeling was to manipulate the bacterial surface charge by producing electro-competent cells enabling charge interactions between the iron particles and the cell wall. Different particle sizes and coatings were tested for their ability to attach to the cell wall and possible labeling mechanisms were elaborated by comparing Gram-positive and -negative bacterial characteristics. With 5-nm citrate-coated particles an iron load of 0.015 ± 0.002 pg Fe/bacterial cell was achieved for Staphylococcus aureus. In both a subcutaneous and a systemic infection model induced by iron-labeled S. aureus bacteria, high resolution MR images allowed for bacterial tracking and provided information on the morphology of organs and the inflammatory response. Conclusion: Labeled with iron oxide particles, in vivo detection of small S. aureus colonies in infection models is feasible by MRI and provides a versatile tool to follow bacterial infections in vivo. The established cell labeling strategy can easily be transferred to other bacterial species and thus provides a conceptual advance in the field of molecular MRI.<br

Pathogenic Activation and Therapeutic Blockage of FcαR-Expressing Polymorphonuclear Leukocytes in IgA Pemphigus

Pathomechanisms in IgA pemphigus are assumed to rely on Fc-dependent cellular activation by antigen-specific IgA autoantibodies; however, models for the disease and more detailed pathophysiologic data are lacking. In this study, we aimed to establish in vitro models of disease for IgA pemphigus, allowing us to study the effects of the interaction of anti-keratinocyte IgA with cell surface FcαRs. Employing multiple in vitro assays, such as a skin cryosection assay and a human skin organ culture model, in this study, we present mechanistic data for the pathogenesis of IgA pemphigus, mediated by anti–desmoglein 3 IgA autoantibodies. Our results reveal that this disease is dependent on FcαR-mediated activation of leukocytes in the epidermis. Importantly, this cell-dependent pathology can be dose-dependently abrogated by peptide-mediated inhibition of FcαR:IgA-Fc interaction, as confirmed in an additional model for IgA-dependent disease, that is, IgA vasculitis. These data suggest that IgA pemphigus can be modeled in vitro and that IgA pemphigus and IgA vasculitis are FcαR-dependent disease entities that can be specifically targeted in these experimental systems

Porcine monocyte subsets differ in the expression of CCR2 and in their responsiveness to CCL2

Monocyte subsets have been shown to differ in the pattern of chemokine receptor expression and their migratory properties, both in human and mouse. Previously we have characterized in the swine several monocyte subpopulations, based on the expression of CD163, Tük4 and SLA-II, which share features with the populations described in human and mouse. Here, we have analysed the expression of different chemokine receptors in the CD163−Tük4+SLA-II− and CD163+Tük4−SLA-II+ populations of porcine monocytes. CD163+Tük4−SLA-II+ monocytes expressed higher CX3CR1 but lower CCR2 and CXCR4 mRNA levels than CD163−Tük4+SLA-II− monocytes. Moreover, porcine CCL2 binding on Tük4+SLA-II− but not on Tük4−SLA-II+ cells was detected by using a CCL2-green fluorescence protein (pCCL2-GFP) fusion protein. Finally, flow cytometric analyses of monocytes recovered after chemotaxis assays show a clear increase in the proportion of Tük4+SLA-II− cells in the fraction migrating toward CCL2, consistent with the polarized CCR2 expression in this monocyte population. The pattern of expression of these chemokine receptors reinforces the similarities of these porcine subsets with their human and mouse counterparts