Did the Bundesbank React to Stock Price Movements?

In this paper, we investigate the relationship between stock returns and short-term interest rates. Identification of the stock return-interest rate relation is solved by using a new technique that relies on the heteroskedasticity of shocks to stock market returns. We suggest some improvements to the identification technique and its justification, as well as providing some new findings. In particular, we ask whether the Bundesbank, prior to the European Central Bank taking responsibility for monetary policy in 1999, reacted systematically to stock price movements. In contrast to the results for the US, our empirical findings for the 1985 - 1998 period show a positive, but statistically insignificant, parameter for the relationship between German stock returns and short-term interest rates at the daily frequency. The same result is found at the monthly frequency. Nevertheless, the confidence bands are wide enough that we cannot entirely exclude the possibility of a reaction at lower frequencies. The results are extremely robust to alternative methods used to identify changes in heteroskedasticity. The evidence is, therefore, inconsistent with the hypothesis of a systematic reaction of the Bundesbank to every wiggle in German stock prices. Both the historical and institutional evidence are supportive of this conclusion. -- In diesem Diskussionspapier untersuchen wir den Zusammenhang zwischen Aktienkursveränderungen und Veränderungen der kurzfristigen Zinssätze. Die ökonometrische Identifikation dieses Zusammenhangs erfolgt mit Hilfe eines neuen Verfahrens, das die Heteroskedastie von Aktienkursveränderungen ausnutzt. Wir schlagen einige Verbesserungen und Rechtfertigungen zu diesem Verfahren vor und liefern neue empirische Befunde. Im Vordergrund der Betrachtungen steht die Frage, ob die Bundesbank vor der Übernahme der geldpolitischen Entscheidungen durch die Europäische Zentralbank im Jahre 1999 systematisch auf Veränderungen der Aktienkurse reagiert hat. Im Unterschied zu den verfügbaren Ergebnissen für die Vereinigten Staaten von Amerika, finden wir auf Basis von Tagesdaten zwar einen positiven, aber statistisch nicht signifikanten Parameter für die Reaktion des kurzfristigen Zinssatzes auf Änderungen des Aktienkurses. Auf der Grundlage von Monatsdaten ist der Parameter ebenfalls positiv und statistisch insignifikant. Die Konfidenzintervalle sind aber sehr breit, so dass eine Reaktion auf der niedrigeren Frequenz nicht völlig ausgeschlossen werden kann. Die empirischen Resultate sind sehr robust gegenüber unterschiedlichen Modellspezifikationen. Die empirische Evidenz widerspricht somit der These einer systematischen Reaktion der Bundesbank auf jede Bewegung am Aktienmarkt, was durch die historischen und institutionellen Gegebenheiten gestützt wird.

Asset Prices in Taylor Rules: Specification, Estimation, and Policy Implications for the ECB

This paper estimates standard and extended Taylor rules for core countries in the euro area, namely France, Germany and Italy, as well as for the ECB. Forward, backward and forecast-based rules are estimated for a variety of samples since the late 1970s. We are particularly interested in the impact of adding asset prices to the standard Taylor rule specification. Since forward-looking Taylor rules are usually estimated via GMM we perform extensive tests for over-identifying restrictions and instrument relevance, a practice generally eschewed in previous work. We find that asset prices can be highly relevant as instruments rather than as separate arguments in policy rules. Backwardlooking Taylor rules, however, cannot be rejected outright. Forecast-based rules perform best using the root mean squared error metric but produce coefficients implying that central banks may be too aggressive at fighting inflation. Encompassing tests are therefore required to select the ?best? policy rule and these suggest that policy rules need to have a mix of forward and forecast-based elements. Furthermore too aggressive reactions to stock prices in particular would have led to an implausible monetary policy. Hence, asset prices appear at best to serve as indicators of the direction of interest rates and not as a variable that the ECB directly reacts to. --reaction function,asset prices

Un atelier pour trois cloîtres : Carennac, Cadouin et Cahors (fin XVe siècle – début XVIe siècle

À la fin du XVe siècle et au début du XVIe siècle, un atelier de sculpteurs itinérants a été particulièrement actif dans le Sud-Ouest de la France, notamment sur les chantiers de Carennac, Cadouin et Cahors, où les cloîtres romans des abbatiales et de la cathédrale ont été dotés d’un nouveau décor. Cet atelier peut vraisemblablement être identifié avec celui de « Maistre Domenge » et d’« Anthoine Constant, son gendre », mentionnés à Bergerac en 1494. Les trois ensembles sculptés (Carennac, Cadouin et Cahors) présentent un décor sculpté proche, et certaines scènes sont reproduites presque à l’identique dans les trois cloîtres. Ces similitudes posent la question de l’utilisation de même modèles par l’atelier Domenge-Constant, mais également celle de la diffusion de ces modèles auprès d’autres sculpteurs qui semblent avoir emprunté certains thèmes à leur répertoire. Enfin, la récurrence de plusieurs thèmes d’un chantier à l’autre invite à s’interroger sur le rôle joué par les sculpteurs dans la mise au point du programme iconographique de ces ensembles.At the end of the XVth century and at the beginning of the XVIth century, a workshop of itinerant sculptors was particularly active in the Southwest of France, in particular in the places of Carennac, Cadouin and Cahors, where the Romanic convents of abbey churches and cathedral were endowed with a new decoration. This workshop can be most probably identified with that of "Maistre Domenge" and of "Anthoine Constant, son gendre", both mentioned in Bergerac in 1494. The Three sculptured sets (Carennac, Cadouin and Cahors) have a similar decoration, and certain scenes are reproduced very precisely in the three convents. These similarities question the use of the same models by the Domenge-Constant workshop, and also the spread of these models, used by other sculptors who seem to have borrowed many themes from their repertoire. Finally, the recurrence of several themes among different buildings invites to wonder about the role played by the sculptors in the drafting of the iconographic programs.Am Ende des 15. und Anfang des 16. Jahrhunderts ist eine reisende Bildhauerwerkstatt im Südwesten Frankreichs äußerst aktiv gewesen, insbesondere bei den Bauvorhaben der Abteien von Carennac und Cadouin sowie der Kathedrale von Cahors, bei denen die romanischen Kreuzgänge jeweils mit einem neuen Dekor versehen wurden. Diese Bildhauerwerkstatt lässt sich vermutlich als jene des „Maistre Domenge“ sowie des „Antoine Constant, seines Schwiegersohns“ identifizieren, die 1494 in Bergerac Erwähnung finden. Die drei skulptierten Ensembles von Carennac, Cadouin und Cahors weisen sehr ähnliches bildhauerisches Dekor auf, wobei einige Szenen in allen drei Kreuzgängen fast identisch wiedergegeben sind. Diese Ähnlichkeit wirft die Frage nach der Verwendung identischer Vorbilder durch die Werkstatt Domenge-Constant auf, sowie jene nach der Verbreitung ebendieser Muster bei anderen Bildhauern, die ihrerseits einige der Themen in ihr Repertoire übernommen zu haben scheinen. Schließlich muss angesichts der Wiederkehr mehrerer Themen an allen drei Bauten auch danach gefragt werden, welche Rolle die Bildhauer selbst beim Entwurf des Bildprogramms der Ensembles gespielt haben

Structural studies of two enzymes in the Raetz pathway of lipid A synthesis, LpxB and LpxH

University of Minnesota Ph.D. dissertation.May 2018. Major: Biochemistry, Molecular Bio, and Biophysics. Advisor: Hideki Aihara. 1 computer file (PDF); xii, 164 pages.Gram-negative bacteria are distinguished from Gram-positive bacteria by the secondary membrane that surrounds their peptidoglycan cell wall. The outer leaflet of this membrane is primarily composed of the glycolipid lipopolysaccharide (LPS), which has lipid A, core oligosaccharide, and O-antigen portions. LPS helps protect Gram-negative bacteria from hydrophobic toxins and, in pathogenic bacteria, from the host immune system. The membrane anchor portion of LPS (lipid A) is responsible for stimulation of the inflammatory response of the mammalian immune system by LPS via activation of the Toll-like receptor 4/myeloid differentiation factor 2 complex. In systemic infections, overstimulation of this receptor causes acute inflammation, which can cause septic shock. Modifications to the LPS, particularly to the lipid A portion, can help bacteria evade the host immune system by disguising the bacteria, modulating the inflammatory response, and inhibiting interactions with antimicrobial host factors. Lipid A is synthesized in the well characterized and largely conserved Raetz pathway in the cytosol and at the cytosolic face of the inner membrane. The non-repeating core oligosaccharide is synthesized on lipid A the cytoplasmic face of the inner membrane, and the repeating O-antigen polysaccharide is attached to the core-lipid A molecule at the periplasmic face of the inner membrane. The completed LPS molecules are then transported to the extracellular leaflet of the outer membrane. Structures of proteins involved in LPS synthesis have proved critical to our understanding of LPS synthesis and transport. Moreover, these structures provide targets for rational design of antibiotics targeting Gram-negative bacteria. As the Raetz pathway is the most conserved part of LPS synthesis, the enzymes of the Raetz pathway provide particularly promising targets for development of broad spectrum antibiotics, such as those needed to treat sepsis. Therefore, I studied the structures of two enzymes in the Raetz pathway (LpxH and LpxB). LpxH was crystallized with the α-helical substrate-binding cap domain in a displaced conformation, suggesting that this domain is highly mobile. The structural dynamics of this domain and their relevance to substrate binding were further explored by hydrogen-deuterium exchange mass spectrometry, molecular dynamics simulations, and activity assays. These data supported a model in which a loop in the core hydrolase domain acts as a wedge to promote opening of the capping helices and allow facile substrate binding between these helices. In addition, the first structure of LpxB was determined showing a Glycosyltransferase B superfamily (GT-B) fold modified by the formation of a novel C-terminally swapped dimer wherein the last 87 residues of one subunit complete the GT-B fold of the other subunit. Furthermore, the binding site of the sugar-donor substrate was identified by a structure of LpxB with the UDP product bound. Activity assays supported the formation of this C-terminally swapped dimer in solution and showed that a surface-exposed hydrophobic patch is critical for LpxB activity, which suggested this patch allows productive membrane association required for substrate binding. Thus, the present research has expanded our understanding of two enzymes important in Gram-negative bacterial physiology that are potential targets for antibiotic development

Investigation of biofuelled combustion and their performance optimisation strategies for internal combustion engines

PhD ThesisThe increasing use of biofuels to replace fossil fuels as well as more stringent emissions regulations for internal combustion engines cause a challenge for the engine manufacturer to build engines that can cope with a large range of fuel properties, but still offer low fuel consumption and very low exhaust emissions. In this work a heavy-duty diesel engine test bed has been built including the fuel and emission analysis equipment suitable for a wide range of biofuels. Also a constant volume spray vessel has been commissioned to optically investigate the macroscopic spray characteristics of different fuels. This vessel was built with the potential investigation of fuel combustion in the future. Four different biofuels, soybean oil methyl ester (SME), palm oil methyl ester (PME), used cooking oil methyl ester (UCOME) and hydrotreated vegetable oil (HVO) in blends of B10, B20, B50 and B100 have been tested, as they are potential candidates to replace mineral diesel in larger scales. The main aim of this project was to investigate the spray and combustion characteristics of various biofuels, their impact on exhaust emissions and performance and the potential optimisation of the control strategy in a heavy-duty Euro V diesel engine. The engine tests revealed that for all biofuels the nitric oxide (NOx) emissions increased compared to mineral diesel (B0), while particulate number (PN), carbon monoxide (CO) and total hydrocarbon (THC) were significantly reduced. The fuel consumption changed according to the heating value and with the three fatty acid methyl esters (FAME) full power was not reached. The macroscopic spray tests showed that lower density fuels, such as HVO, have slower penetration speeds, but wider spray cone angle resulting in better fuel-air mixing conditions. As the engine fuel injection is based on a volumetric injection the heating value and fuel density are mainly influencing the spray characteristics on the engine. In the last part the engine power has been successfully restored for all biofuels and the exhaust emissions have been reduced below the B0 benchmark limits by applying a new engine control strategy showing that the use of neat biofuels can be used on heavy-duty diesel engines without any modifications to the engine hardware and still passing the current emission regulations.Engineering and Physical Sciences Research Council (EPSRC) as well as Cummins Lt

Longitudinal emittance blow-up and hollow bunches with arbitrarily-shaped noise in the SPS as LHC test-bed

In the SPS the LHC type high intensity beam can be kept stable longitudinally during acceleration to 450 GeV/c by using the 800 MHz higher harmonic system and, in addition, by making a longitudinal controlled emittance increase by a factor of about 1.5. This latter is obtained by applying band-limited RF phase noise via the main RF system. In LHC itself, which does not have a higher harmonic system, an emittance increase by a factor 2.5 is required. This was attempted in the SPS, as a test-bed for LHC, with shaped RF phase noise and with the 800 MHz system switched off - limiting the maximum stable beam intensity. The emittance of a single (LHC-) pilot bunch has been blown up to a factor 2.5 in coast at 270 GeV/c with a final âgoodâ bunch shape. It remains to be demonstrated that this technique can also be applied successfully for many high intensity bunches with differing synchrotron frequency profiles along the batches. Also a first very quick test to create hollow bunches was done

Did the Bundesbank React to Stock Price Movements?

In this paper, we investigate the relationship between stock returns and short-term interest rates. Identification of the stock return-interest rate relation is solved by using a new technique that relies on the heteroskedasticity of shocks to stock market returns. We suggest some improvements to the identification technique and its justification, as well as providing some new findings. In particular, we ask whether the Bundesbank, prior to the European Central Bank taking responsibility for monetary policy in 1999, reacted systematically to stock price movements. In contrast to the results for the US, our empirical findings for the 1985 - 1998 period show a positive, but statistically insignificant, parameter for the relationship between German stock returns and short-term interest rates at the daily frequency. The same result is found at the monthly frequency. Nevertheless, the confidence bands are wide enough that we cannot entirely exclude the possibility of a reaction at lower frequencies. The results are extremely robust to alternative methods used to identify changes in heteroskedasticity. The evidence is, therefore, inconsistent with the hypothesis of a systematic reaction of the Bundesbank to every wiggle in German stock prices. Both the historical and institutional evidence are supportive of this conclusion.In diesem Diskussionspapier untersuchen wir den Zusammenhang zwischen Aktienkursveränderungen und Veränderungen der kurzfristigen Zinssätze. Die ökonometrische Identifikation dieses Zusammenhangs erfolgt mit Hilfe eines neuen Verfahrens, das die Heteroskedastie von Aktienkursveränderungen ausnutzt. Wir schlagen einige Verbesserungen und Rechtfertigungen zu diesem Verfahren vor und liefern neue empirische Befunde. Im Vordergrund der Betrachtungen steht die Frage, ob die Bundesbank vor der Übernahme der geldpolitischen Entscheidungen durch die Europäische Zentralbank im Jahre 1999 systematisch auf Veränderungen der Aktienkurse reagiert hat. Im Unterschied zu den verfügbaren Ergebnissen für die Vereinigten Staaten von Amerika, finden wir auf Basis von Tagesdaten zwar einen positiven, aber statistisch nicht signifikanten Parameter für die Reaktion des kurzfristigen Zinssatzes auf Änderungen des Aktienkurses. Auf der Grundlage von Monatsdaten ist der Parameter ebenfalls positiv und statistisch insignifikant. Die Konfidenzintervalle sind aber sehr breit, so dass eine Reaktion auf der niedrigeren Frequenz nicht völlig ausgeschlossen werden kann. Die empirischen Resultate sind sehr robust gegenüber unterschiedlichen Modellspezifikationen. Die empirische Evidenz widerspricht somit der These einer systematischen Reaktion der Bundesbank auf jede Bewegung am Aktienmarkt, was durch die historischen und institutionellen Gegebenheiten gestützt wird

Self‐guided clinical cases for medical students based on postmortem CT scans of cadavers

In the summer of 2009, we began full body computed tomography (CT) scanning of the pre‐embalmed cadavers in the University of Michigan Medical School (UMMS) dissection lab. We theorized that implementing web‐based, self‐guided clinical cases based on postmortem CT (PMCT) scans would result in increased student appreciation for the clinical relevance of anatomy, increased knowledge of cross‐sectional anatomy, and increased ability to identify common pathologies on CT scans. The PMCT scan of each cadaver was produced as a DICOM dataset, and then converted into a Quicktime movie file using Osirix software. Clinical cases were researched and written by the authors, and consist of at least one Quicktime movie of a PMCT scan surrounded by a novel navigation interface. To assess the value of these clinical cases we surveyed medical students at UMMS who are currently using the clinical cases in their coursework. Students felt the clinical cases increased the clinical relevance of anatomy (mean response 7.77/10), increased their confidence finding anatomical structures on CT (7.00/10), and increased their confidence recognizing common pathologies on CT (6.17/10). Students also felt these clinical cases helped them synthesize material from numerous courses into an overall picture of a given disease process (7.01/10). These results support the conclusion that our clinical cases help to show students why the anatomy they are learning is foundational to their other coursework. We would recommend the use of similar clinical cases to any medical school utilizing cadaver dissection as a primary teaching method in anatomy education. Clin. Anat. 24:655–663, 2011. © 2011 Wiley‐Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87056/1/21143_ftp.pd

Particulate number and NOx trade-off comparisons between HVO and mineral diesel in HD applications

The increase in worldwide greenhouse gas emissions and costs for fossil fuels are forcing fuel suppliers and engine manufacturers to consider more sustainable alternatives for powering internal combustion engines. One very promising equivalent to mineral diesel fuel is hydrotreated vegetable oil (HVO) as it is highly paraffinic and offers similar combustion characteristics. This fuel offer the potential of not requiring further engine hardware modification together with correspondingly lower exhaust gas emissions and better fuel consumption than mineral diesel. In this paper the spray and combustion characteristics of HVO and its blends are investigated and compared with mineral diesel (European standard). Evidence of the reported reductions in NOx emissions has proven contradictory with some researchers reporting large reductions, whilst others measured no differences. This paper reports the results from comparison of three different experimental tests methods using diesel/HVO binary fuel blends. The macroscopic spray characteristics have been investigated and quantified using a constant volume spray vessel. Engine performance and exhaust emissions have also been characterised using a HD diesel engine in its original configuration (mineral diesel fuel-ready) and then in a recalibrated configuration optimised for HVO fuel. The results show that the engine injection control and also the fuel quality can influence the formation of NOx and particulate matter significantly. In-particular a potential pilot injection proved highly influential upon whether NOx emissions were reduced or not. When optimising the fuel injection, a reduction in NOx emissions of up to 18% or reductions of PN of up to 42–66% were achieved with simultaneous savings in fuel consumption of 4.3%

Modélisation de maladies neurodégénératives à l'aide de cellules souches pluripotentes induites humaines

La technologie de reprogrammation de cellules somatiques en cellules souches pluripotentes induites (iPS) offre aujourd hui l opportunité de modéliser des maladies neurodégénératives et d étudier des neurones de patients. Nous avons utilisé cette technologie pour générer deux modèles de maladies neurodégénératives : la mucopolysaccharidose de type IIIB (MPSIIIB) et la forme ALS2 de la sclérose latérale amyotrophique (SLA). Dans le modèle MPSIIIB, nous avons montré que les iPS et les neurones de patients présentaient des défauts caractéristiques de la pathologie telle que l accumulation de vésicules de surcharge. Des altérations de l appareil de Golgi dans ces cellules ont également été mises en évidence. Une analyse du transcriptome de précurseurs neuraux MPSIIIB a montré des modifications transcriptionnelles touchant notamment des gènes impliqués dans les interactions de la cellule avec la matrice extracellulaire. Ainsi, dans une seconde étude, des altérations de la migration et de l orientation de cellules de souris mutantes MPSIIIB ou de patients ont été démontrées. Ces altérations pourraient être responsables des perturbations de la neurogénèse et de la neuritogénèse chez les enfants malades. Dans le modèle SLA/ALS2, nous avons montré que les neurones de patients présentaient des défauts incluant une diminution de la surface des endosomes et des anomalies de la croissance neuritique. Alors qu il n existait jusqu alors aucun modèle cellulaire pertinent reproduisant cette maladie, ce modèle permettra à présent d étudier les processus physiopathologiques impliqués dans la maladie. En conclusion, la génération de cellules iPS permet de modéliser des maladies neurodégénératives et d étudier les processus physiopathologiques qui sont associés sur des neurones humains en culture. Ces modèles cellulaires pourraient permettre dans un avenir proche de réaliser des criblages de molécules à visée thérapeutiqueReprogramming technology of somatic cells in induced pluripotent stem cells (iPS) now offers the opportunity to model neurodegenerative diseases and to study patient s neurons. We used this technology for generating two models of neurodegenerative diseases: the muccopolysaccharidosis type IIIB (MPSIIIB) and the ALS2 form of amyotrophic lateral sclerosis (ALS). In the MPSIIIB model, we have shown that iPS and neurons of patients had characteristic defects of the disease such as the accumulation of storage vesicles. Alterations of the Golgi apparatus in these cells were also highlighted. Transcriptome analysis of MPSIIIB neural precursors showed transcriptional changes involving particularly genes implicated in cell-extracellular matrix interactions. Thus, in a subsequent study, alterations of migration and orientation of MPSIIIB mutant mouse cells and MPSIIIB patients cells have been demonstrated. These alterations may be responsible for the disruption of neurogenesis and neuritogenesis in sick children. In the ALS2 model, we have shown that patients neurons had defects including decreased endosomes surface and abnormal neurite outgrowth. As there was previously no relevant cellular model reproducing the disease, this model will now allow the study of physiopathological processes involved in the disease. In conclusion, the generation of iPS cells allows to model neurodegenerative diseases and to study associated physiopathological processes on cultured human neurons. These cell models could allow in the near future the screening of molecules of potential therapeutical interestPARIS5-Bibliotheque electronique (751069902) / SudocSudocFranceF