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Die reimaginierte TV-Serie Battlestar Galactica gilt als ein Höhepunkt gegenwärtiger Science Fiction. Sie spiegelt aktuelle soziopolitische Brennpunkte unserer Gesellschaft und unserer Zeit in all ihrer Kontroversität wider. Darüberhinaus stellt sie mithilfe der Zylonen, humanoiden kybernetischen Organismen, die Frage nach dem Menschen, seinem Bewusstsein und seiner Subjektivität radikal neu. Der folgende Beitrag versucht, diese Radikalität, mit der Battlestar Galactica das Verhältnis von Mensch und Maschine verhandelt, anhand von diversen Reloads herauszustellen.
Der dänische Anästhesist Björn Ibsen : ein Pionier der Langzeitbeatmung über die oberen Luftwege
(2009)
The Danish anaesthesiologist Björn Ibsen should be placed among the pioneers of the development of long term ventilation by the upper airways (in this publication I have only briefly mentioned his other contributions, in particular the development of Intensive care medicine). Ibsen learned the basics of anaesthesia in the USA (1949/50). Returning to Denmark he worked as independent anaesthesiologist. In 1952, together with Mogens Björneboe, he treated newborn child who suffered from Tetanus. The treatment consisted of barbiturates and curare, in an attempt to suppress the muscular cramps of the child. The child was ventilated with manual positive pressure during the treatment. The child died but this attempt of treatment proved to be an important step in the development of long term ventilation by the upper airways. The core of this work is Ibsen’s introduction of the new treatment for treating poliomyelitis patients with respiratory insufficiency. In 1952, a severe poliomyelitis epidemic hit Copenhagen. At the time the normal treatment of poliomyelitis patients with respiratory failure was passive negative pressure ventilation. At the hospital treating the poliomyelitis patients in Copenhagen there were by far not enough respirators to treat all the severely ill patients. As several patients died from respiratory failure the epidemiologist Lassen was lead to try out a new and untested treatment, and contacted Ibsen. Because I have been able to find the records of the patient, it has now been possible to describe exactly what happened on the 27. August 1952, as Ibsen demonstrated his new treatment on a 12-year old girl. Ibsen intended to ventilate the girl by a tracheotomy, with manual positive pressure from an oxygen filled bag (he had read about his method in an American paper from 1950. here the method was being used as supplement to the negative pressure ventilation from the Iron Lung). Ventilating the patient, however, was only possible after Ibsen had anaesthetised her with barbiturate. The girl survived. As a direct consequence the treatment of the poliomyelitis patients with respiratory problems was changed to follow Ibsen’s directions. Numerous helpers would within days ventilate until 75 patients until they recovered (or died). I do not know for how long the longest ventilation-period was, but I presume it was several weeks. After the epidemic Ibsen found time to develop his method. In 1953 he treated a child with tetanus with anaesthetic drugs and curare, and had it ventilated by a tracheotomy. This positive pressure ventilation by the upper airways of an unconscious patient lasted 17 days. This time the patient survived. It was only later in his life that Ibsen received international recognition for his work (directly after the poliomyelitis epidemic it was Lassen who took the glory). He remained a modest man, something I have been able to verify my self when I interviewed him shortly before his death. He died the 7th of August 2007.
Information sent to and received by cells is essential for a homeostatic development of tissues and organs. These same signals are responsible for the good functioning of lymphatic organs and therefore govern the immune response. Dysfunctioning of the signaling networks is related to pathological situations, among which one can find cancer and auto-immune diseases. Intercellular communication involves the synthesis and the adjustment of signals by the secreting/emitting cell in order to reach the needed threshold. Diffusion of the signal to the target cell in addition to its interpretation lead to functional changes like cell migration and aggregation. Individual cells such as bacteria find food or increase their virulence through taxis (directional stimulus) and/or kinesis (speed stimulus). Immune cells appear to use the same processes to find bacteria and cellular debris, as well as to perform the cellular dance observed in germinal centers. This behavior is a result of an up or down regulation of specific signals that suggest to B and T-cells the paths to follow. Furthermore, cell segregation in the white pulp of the spleen, was also shown to be a result of a tight adjustment of T-cell kinesis. Restriction to cellular tracks and other experimentally provided measurements does not ensure a full comprehension of the observed cellular behavior. Thus, the study of patterns opens new gates to our understanding of the immune system. With the help of the agent-based modeling technique, cellular migration and aggregation are investigated in response to various cell-cell interactions. This work aims to explore different mechanisms that lead to cellular migration and aggregation, by defining the emergent properties of interest and that will help distinguish between interactions, starting by a simple look at the emergent patterns, followed by an analysis of their size, their degree of aggregation and the effective communication distances. Finally, the results obtained from the in silico experiments provided a guideline to differentiate between many cell-cell interactions under specific circumstances. Chemotaxis and phototaxis with and without diffusive cellular motion were shown to be distinguishable through an analysis of the emerging aggregation profiles.
Loss of vascular barrier function causes leak of fluid and proteins into tissues, extensive leak leads to shock and death. Barriers are largely formed by endothelial cell-cell contacts built up by VE-cadherin and are under the control of RhoGTPases. Here we show that a natural plasmin digest product of fibrin, peptide Bß15-42 (also called FX06), significantly reduces vascular leak and mortality in animal models for Dengue shock syndrome. The ability of Bß15-42 to preserve endothelial barriers is confirmed in rats i.v.-injected with LPS. In endothelial cells, Bß15-42 prevents thrombin-induced stress fiber formation, myosin light chain phosphorylation and RhoA activation. The molecular key for the protective effect of Bß15-42 is the src kinase Fyn, which associates with VE-cadherin-containing junctions. Following exposure to Bß15-42 Fyn dissociates from VE-cadherin and associates with p190RhoGAP, a known antagonists of RhoA activation. The role of Fyn in transducing effects of Bß15-42 is confirmed in Fyn -/- mice, where the peptide is unable to reduce LPS-induced lung edema, whereas in wild type littermates the peptide significantly reduces leak. Our results demonstrate a novel function for Bß15-42. Formerly mainly considered as a degradation product occurring after fibrin inactivation, it has now to be considered as a signaling molecule. It stabilizes endothelial barriers and thus could be an attractive adjuvant in the treatment of shock.
Introduction: Immune paralysis with massive T-cell apoptosis is a central pathogenic event during sepsis and correlates with septic patient mortality. Previous observations implied a crucial role of peroxisome proliferator-activated receptor gamma (PPARγ) during T-cell apoptosis.
Methods: To elucidate mechanisms of PPARγ-induced T-cell depletion, we used an endotoxin model as well as the caecal ligation and puncture sepsis model to imitate septic conditions in wild-type versus conditional PPARγ knockout (KO) mice.
Results: PPARγ KO mice showed a marked survival advantage compared with control mice. Their T cells were substantially protected against sepsis-induced death and showed a significantly higher expression of the pro-survival factor IL-2. Since PPARγ is described to repress nuclear factor of activated T cells (NFAT) transactivation and concomitant IL-2 expression, we propose inhibition of NFAT as the underlying mechanism allowing T-cell apoptosis. Corroborating our hypothesis, we observed up-regulation of the pro-apoptotic protein BIM and downregulation of the anti-apoptotic protein Bcl-2 in control mice, which are downstream effector proteins of IL-2 receptor signaling. Application of a neutralizing anti-IL-2 antibody reversed the pro-survival effect of PPARγ-deficient T cells and confirmed IL-2-dependent apoptosis during sepsis.
Conclusion: Apparently antagonizing PPARγ in T cells might improve their survival during sepsis, which concomitantly enhances defence mechanisms and possibly provokes an increased survival of septic patients.
Background Gamma-aminobutyric acid (GABA) is an important inhibitory neurotransmitter which mainly mediates its effects on neurons via ionotropic (GABAA) and metabotropic (GABAB) receptors. GABAB receptors are widely expressed in the central and the peripheral nervous system. Although there is evidence for a key function of GABAB receptors in the modulation of pain, the relative contribution of peripherally- versus centrally-expressed GABAB receptors is unclear. Results In order to elucidate the functional relevance of GABAB receptors expressed in peripheral nociceptive neurons in pain modulation we generated and analyzed conditional mouse mutants lacking functional GABAB(1) subunit specifically in nociceptors, preserving expression in the spinal cord and brain (SNS-GABAB(1)-/- mice). Lack of the GABAB(1) subunit precludes the assembly of functional GABAB receptor. We analyzed SNS-GABAB(1)-/- mice and their control littermates in several models of acute and neuropathic pain. Electrophysiological studies on peripheral afferents revealed higher firing frequencies in SNS-GABAB(1)-/- mice compared to corresponding control littermates. However no differences were seen in basal nociceptive sensitivity between these groups. The development of neuropathic and chronic inflammatory pain was similar across the two genotypes. The duration of nocifensive responses evoked by intraplantar formalin injection was prolonged in the SNS-GABAB(1)-/- animals as compared to their control littermates. Pharmacological experiments revealed that systemic baclofen-induced inhibition of formalin-induced nociceptive behaviors was not dependent upon GABAB(1) expression in nociceptors. Conclusion This study addressed contribution of GABAB receptors expressed on primary afferent nociceptive fibers to the modulation of pain. We observed that neither the development of acute and chronic pain nor the analgesic effects of a systematically-delivered GABAB agonist was significantly changed upon a specific deletion of GABAB receptors from peripheral nociceptive neurons in vivo. This lets us conclude that GABAB receptors in the peripheral nervous system play a less important role than those in the central nervous system in the regulation of pain.
In der vorliegenden Arbeit wurden die Angaben von 355 Patientinnen ausgewertet, die zwischen Januar 2000 und September 2007 aufgrund eines metastasierten Brustkrebses im onkologischen Fachzentrum Frankfurt Nord-Ost behandelt worden sind. Die 5-JÜR nach Kaplan-Meier liegt im untersuchten Kollektiv bei 76 %. Die Wahrscheinlichkeit, fünf Jahre nach Erstdiagnose einer Metastasierung überlebt zu haben beträgt 50 %. Die mittlere Überlebenszeit ab Metastasierung liegt bei 7,4 Jahren. Die Wahrscheinlichkeit für metastasenfreies Überleben nach fünf bzw. zehn Jahren beträgt 60 % bzw. 44 %. Im univariaten Log-Rank-Verfahren weisen Patientinnen mit folgenden Charakteristika eine bessere Prognose hinsichtlich der Gesamtüberlebenswahrscheinlichkeit auf: Prämeno-pausaler Status bei ED, Ablatio mammae, CMF-Chemotherapie sowie operative und antihormonelle Therapie der Fernmetastasen. Als prognostisch ungünstig gelten: Positiver Nodalstatus, niedriger Differenzierungsgrad, invasiv duktaler oder lobulärer Tumortyp, höheres UICC-Stadium, Stadium > 2 der St. Gallener Risikoklassifikation, First-Line-Chemotherapie, R1-resezierte Tumoren, adjuvante Chemotherapie, > 3 verschiedene Metastasenorte und zytostatische Metastasentherapie. Die Lokalisation der Fernmetastasen ermöglicht eine differenziertere prognostische Einschätzung: Viszerale Metastasen, vor allem in der Leber und im ZNS, beeinflussen die Überlebenszeit negativ. Im Verlauf auftretende Metastasen im Abdomen/ Peritoneum gehen ebenfalls mit einer schlechteren Prognose einher. Bei ossärer Metastasierung hingegen kann mit einem benigneren Krankheitsverlauf gerechnet werden, ebenso bei Erstmanifestation der Metastasen in der Haut und/oder den Weichteilen. In der multivariaten Cox-Analyse übt die Leber als primärer Metastasierungsort den größten negativen Einfluss auf die Überlebens-wahrscheinlichkeit aus. Auch eine hohe Anzahl befallener Lymphknoten, Metastasen an > 3 verschiedenen Lokalisationen sowie ein positiver Resektionsrand führen zu signifikant schlechteren Überlebensraten. Bessere Prognosen besitzen Patientinnen, die zum Diagnosezeitpunkt prämenopausal gewesen sind und deren Metastasen im Verlauf antihormonell therapiert werden konnten. In der Cox-Regressionsanalyse erwiesen sich das Grading und der Nodalstatus als unabhängige Prognoseparameter hinsichtlich des metastasenfreien Überlebens. Demnach gilt: Je schlechter der Differenzierungsgrad eines Tumors und je mehr Lymphknoten befallen sind, desto niedriger ist die Wahrscheinlichkeit nach zehn Jahren metastasenfrei überlebt zu haben.
Misselling through agents
(2009)
This paper analyzes the implications of the inherent conflict between two tasks performed by direct marketing agents: prospecting for customers and advising on the product's "suitability" for the specific needs of customers. When structuring sales-force compensation, firms trade off the expected losses from "misselling" unsuitable products with the agency costs of providing marketing incentives. We characterize how the equilibrium amount of misselling (and thus the scope of policy intervention) depends on features of the agency problem including: the internal organization of a firm's sales process, the transparency of its commission structure, and the steepness of its agents' sales incentives. JEL Classification: D18 (Consumer Protection), D83 (Search; Learning; Information and Knowledge), M31 (Marketing), M52 (Compensation and Compensation Methods and Their Effects).
This paper considers a firm that has to delegate to an agent, such as a mortgage broker or a security dealer, the twin tasks of approaching and advising customers. The main contractual restriction, in particular in light of related research in Inderst and Ottaviani (2007), is that the firm can only compensate the agent through commissions. This standard contracting restriction has the following key implications. First, the firm can only ensure internal compliance to a "standard of sales", in terms of advice for the customer, if this standard is not too high. Second, if this is still feasible, then a higher standard is associated with higher, instead of lower, sales commissions. Third, once the limit for internal compliance is approached, tougher regulation and prosecution of "misselling" have (almost) no effect on the prevailing standard. Besides having practical implications, in particular on how to (re-)regulate the sale of financial products, the novel model, which embeds a problem of advice into a framework with repeated interactions, may also be of separate interest for future work on sales force compensation. JEL Classification: D18 (Consumer Protection), D83 (Search; Learning; Information and Knowledge), M31 (Marketing), M52 (Compensation and Compensation Methods and Their Effects).
This article shows that investors financing a portfolio of projects may use the depth of their financial pockets to overcome entrepreneurial incentive problems. Competition for scarce informed capital at the refinancing stage strengthens investors’ bargaining positions. And yet, entrepreneurs’ incentives may be improved, because projects funded by investors with ‘‘shallow pockets’’ must have not only a positive net present value at the refinancing stage, but one that is higher than that of competing portfolio projects. Our article may help understand provisions used in venture capital finance that limit a fund’s initial capital and make it difficult to add more capital once the initial venture capital fund is raised. (JEL G24, G31)
We analyze how two key managerial tasks interact: that of growing the business through creating new investment opportunities and that of providing accurate information about these opportunities in the corporate budgeting process. We show how this interaction endogenously biases managers toward overinvesting in their own projects. This bias is exacerbated if managers compete for limited resources in an internal capital market, which provides us with a novel theory of the boundaries of the firm. Finally, managers of more risky and less profitable divisions should obtain steeper incentives to facilitate efficient investment decisions.
We present a simple model of personal finance in which an incumbent lender has an information advantage vis-a-vis both potential competitors and households. In order to extract more consumer surplus, a lender with sufficient market power may engage in "irresponsible"lending, approving credit even if this is knowingly against a household’s best interest. Unless rival lenders are equally well informed, competition may reduce welfare. This holds, in particular, if less informed rivals can free ride on the incumbent’s superior screening ability.
This paper argues that banks must be sufficiently levered to have first-best incentives to make new risky loans. This result, which is at odds with the notion that leverage invariably leads to excessive risk taking, derives from two key premises that focus squarely on the role of banks as informed lenders. First, banks finance projects that they do not own, which implies that they cannot extract all the profits. Second, banks conduct a credit risk analysis before making new loans. Our model may help understand why banks take on additional unsecured debt, such as unsecured deposits and subordinated loans, over and above their existing deposit base. It may also help understand why banks and finance companies have similar leverage ratios, even though the latter are not deposit takers and hence not subject to the same regulatory capital requirements as banks.
This paper shows that active investors, such as venture capitalists, can affect the speed at which new ventures grow. In the absence of product market competition, new ventures financed by active investors grow faster initially, though in the long run those financed by passive investors are able to catch up. By contrast, in a competitive product market, new ventures financed by active investors may prey on rivals that are financed by passive investors by “strategically overinvesting” early on, resulting in long-run differences in investment, profits, and firm growth. The value of active investors is greater in highly competitive industries as well as in industries with learning curves, economies of scope, and network effects, as is typical for many “new economy” industries. For such industries, our model predicts that start-ups with access to venture capital may dominate their industry peers in the long run. JEL Classifications: G24; G32 Keywords: Venture capital; dynamic investment; product market competition
We study a model of “information-based entrenchment” in which the CEO has private information that the board needs to make an efficient replacement decision. Eliciting the CEO’s private information is costly, as it implies that the board must pay the CEO both higher severance pay and higher on-the-job pay. While higher CEO pay is associated with higher turnover in our model, there is too little turnover in equilibrium. Our model makes novel empirical predictions relating CEO turnover, severance pay, and on-the-job pay to firm-level attributes such as size, corporate governance, and the quality of the firm’s accounting system.
Corporate borrowers care about the overall riskiness of a bank’s operations as their continued access to credit may rely on the bank’s ability to roll over loans or to expand existing credit facilities. As we show, a key implication of this observation is that increasing competition among banks should have an asymmetric impact on banks’ incentives to take on risk: Banks that are already riskier will take on yet more risk, while their safer rivals will become even more prudent. Our results offer new guidance for bank supervision in an increasingly competitive environment and may help to explain existing, ambiguous findings on the relationship between competition and risk-taking in banking. Furthermore, our results stress the beneficial role that competition can have for financial stability as it turns a bank’s "prudence" into an important competitive advantage.
This paper presents a novel model of the lending process that takes into account that loan officers must spend time and effort to originate new loans. Besides generating predictions on loan officers’ compensation and its interaction with the loan review process, the model sheds light on why competition could lead to excessively low lending standards. We also show how more intense competition may fasten the adoption of credit scoring. More generally, hard-information lending techniques such as credit scoring allow to give loan officers high-powered incentives without compromising the integrity and quality of the loan approval process. The model is finally applied to study the implications of loan sales on the adopted lending process and lending standard.
Inhalt: Prof. Dr. Helmut Siekmann : Stellungnahme für die öffentliche Anhörung des Haushalts- und Finanzausschusses des Landtags Nordrhein-Westfalen am 29. Oktober 2009 Gesetzentwurf der Landesregierung NRW : LANDTAG NORDRHEIN-WESTFALEN 14. Wahlperiode - Drucksache 14/9380 - 10.06.2009 Gesetz über die Feststellung eines zweiten Nachtrags zum Haushaltsplan des Landes Nordrhein-Westfalen für das Haushaltsjahr 2009 und zur Änderung des Gesetzes zur Errichtung eines Fonds für eine Inanspruchnahme des Landes Nordrhein-Westfalen aus der im Zusammenhang mit der Risikoabschirmung zugunsten der WestLB AG erklärten Garantie (Zweites Nachtragshaushaltsgesetz 2009) - Auszug Ergänzung der Landesregierung NRW zu dem Gesetzentwurf der Landesregierung - Drucksache 14/9380 (Zweites Nachtragshaushaltsgesetz 2009) - Drucksache 14/9510 – 01.07.2009 - Auszug Zweite Ergänzung der Landesregierung zu dem Gesetzentwurf der Landesregierung - Drucksachen 14/9380 und 14/9510 (1. Ergänzung) - Drucksache 14/9910 – 02.10.2009 - Auszug
Aus der Vielzahl der damit verbundenen Probleme sollen im Folgenden einige Aspekte etwas näher betrachtet werden. Dabei sollen die Maßnahmen zur unmittelbaren Krisenbewältigung ausgeklammert werden. Auch können die drängenden Fragen nach der Rolle der Geldpolitik sowie der globalen außenwirtschaftlichen Ungleichgewichte, die beide einen erheblichen, wenn nicht gar entscheidenden Beitrag zur Entstehung der Instabilitäten geleistet haben,19 hier nicht näher behandelt werden. Das Hauptaugenmerk soll stattdessen auf folgende Fragenkreise gelegt werden: I. Der Beitrag der Rechtsordnung zu Entstehung und Verlauf der Krise II. Verbesserung von Aufsicht und Kontrolle als Kern einer Neugestaltung III. Die Rolle der Ratingagenturen IV. Die reale Bedeutung von Finanzmärkten und Finanzinstitutionen V. Überlegungen zur Prävention Dabei sollen nicht Detailregelungen im Vordergrund der Betrachtung stehen, sondern die grundsätzliche Rolle der Rechtsordnung für die Stabilisierung der Finanzmärkte.
Der Präsident der Europäischen Kommission, José Manuel Barroso, hat im Oktober 2008 eine Gruppe von Sachverständigen unter Vorsitz des früheren Präsidenten des Internationalen Währungsfonds (IWF) und der Banque de France, Jacques de Larosière, mit der Ausarbeitung von Ratschlägen zur Zukunft der europäischen Finanzregulierung („financial regulation“) und Aufsicht („supervision“) beauftragt. Die Gruppe hat ihren Bericht am 25. Februar 2009 vorgelegt. Kapitel III des Berichts behandelt das Aufsichtssystem auf EU-Ebene und gelangt im Wesentlichen zu zwei Empfehlungen: - Errichtung einer präventiv tätigen, institutsübergreifenden („macroprudential“) Aufsichtseinrichtung mit dem Namen „European Systemic Risk Council“ [ESRC] - Umwandlung der bestehenden Ebene-3 Ausschüsse („3L3 committees“) in ein neues europäisches System von Finanzaufsicht [ESFS] mit hoheitlichen Funktionen Vor allem die geforderte Neustrukturierung der Aufsicht ist unter verschiedenen Gesichtspunkten kritisch zu würdigen. Die Erwägungen konzentrieren sich dabei auf die Frage, ob die Umsetzung der Vorschläge ohne Änderung des primären Gemeinschaftsrechts möglich erscheint. Der Abschluss von separaten Verwaltungsabkommen oder von Staatsverträgen, mit denen ad hoc neue Einrichtungen geschaffen werden könnten, soll im Folgenden nicht weiter untersucht werden. Zwar könnte auf diese Weise ein vollständiger Rechtsrahmen für Aufsichtseinrichtungen auf EU-Ebene geschaffen werden. Er könnte auch die Grundlage für die Übertragung von Hoheitsbefugnissen bilden, doch wäre dies mit gravierenden Nachteilen verbunden. Es ist keineswegs sicher, dass alle Mitglieder der EU eine solche Vereinbarung unterzeichnen würden, so dass unterschiedliche Aufsichtssysteme entstehen würden. Einer der Hauptgründe für eine Aufsicht auf europäischer Ebene würde verfehlt. Zum anderen würde eine institutionelle Parallelstruktur im Kernbereich der EU, dem gemeinsamen Binnenmarkt mit den Grundfreiheiten, geschaffen, die zahlreiche gravierende Probleme der Koordination und Abstimmung zwischen diesen, voneinander unabhängigen Systemen hervorrufen würde.