710 resultados para Higher-derivative electromagnetism


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In models where privately informed agents interact, agents may need to formhigher order expectations, i.e. expectations of other agents' expectations. This paper develops a tractable framework for solving and analyzing linear dynamic rational expectationsmodels in which privately informed agents form higher order expectations. The frameworkis used to demonstrate that the well-known problem of the infinite regress of expectationsidentified by Townsend (1983) can be approximated to an arbitrary accuracy with a finitedimensional representation under quite general conditions. The paper is constructive andpresents a fixed point algorithm for finding an accurate solution and provides weak conditions that ensure that a fixed point exists. To help intuition, Singleton's (1987) asset pricingmodel with disparately informed traders is used as a vehicle for the paper.

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The synthesis of a photoreactive derivative of the human leukocyte antigen-A1 (HLA-A1)-restricted MAGE-1 peptide 161-169 (EADPTGHSY) is described. Using conventional automated solid-phase peptide synthesis, a photoreactive derivative of this peptide was synthesized by replacing histidine-167 with photo-reactive N-beta-4-azidosalicyloyl-L-2,3-diaminopropionic acid. The C-terminal tyrosine was incorporated as phosphotyrosine. This peptide derivative was radioiodinated in the presence of chloramine T. This iodination took place selectively at the photoreactive group, because the phosphate ester prevented tyrosine iodination. Following dephosphorylation with alkaline phosphatase and chromatographic purification, the radiolabeled peptide derivative was incubated with cells expressing HLA-A1 or other HLA molecules. Photoactivation resulted in efficient photoaffinity labeling of HLA-A1. Other HLA molecules or other cellular components were not detectably labeled. This labeling was inhibited by HLA-A1 but not by HLA-A2-binding peptides. This synthesis is generally applicable and can also be adapted to the synthesis of well-defined radiolabeled nonphotoreactive peptide derivatives.

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Doctoral dissertation, University of Helsinki

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We present a rule-based Huet’s style anti-unification algorithm for simply-typed lambda-terms in ɳ long β normal form, which computes a least general higher-order pattern generalization. For a pair of arbitrary terms of the same type, such a generalization always exists and is unique modulo α equivalence and variable renaming. The algorithm computes it in cubic time within linear space. It has been implemented and the code is freely available

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OBJECTIVES: To determine HIV-1 RNA in cerebrospinal fluid (CSF) of successfully treated patients and to evaluate if combination antiretroviral treatments with higher central nervous system penetration-effectiveness (CPE) achieve better CSF viral suppression. METHODS: Viral loads (VLs) and drug concentrations of lopinavir, atazanavir, and efavirenz were measured in plasma and CSF. The CPE was calculated using 2 different methods. RESULTS: The authors analyzed 87 CSF samples of 60 patients. In 4 CSF samples, HIV-1 RNA was detectable with 43-82 copies per milliliter. Median CPE in patients with detectable CSF VL was significantly lower compared with individuals with undetectable VL: CPE of 1.0 (range, 1.0-1.5) versus 2.3 (range, 1.0-3.5) using the method of 2008 (P = 0.011) and CPE of 6 (range, 6-8) versus 8 (range, 5-12) using the method of 2010 (P = 0.022). The extrapolated CSF trough levels for atazanavir (n = 12) were clearly above the 50% inhibitory concentration (IC50) in only 25% of samples; both patients on atazanavir/ritonavir with detectable CSF HIV-1 RNA had trough levels in the range of the presumed IC50. The extrapolated CSF trough level for lopinavir (n = 42) and efavirenz (n = 18) were above the IC50 in 98% and 78%, respectively, of samples, including the patients with detectable CSF HIV-1 RNA. CONCLUSIONS: This study suggests that treatment regimens with high intracerebral efficacy reflected by a high CPE score are essential to achieve CSF HIV-1 RNA suppression. The CPE score including all drug components was a better predictor for treatment failure in the CSF than the sole concentrations of protease inhibitor or nonnucleoside reverse transcriptase inhibitor in plasma or CSF.

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BACKGROUND: Congenital diaphragmatic hernia (CDH) is associated with pulmonary hypertension and death. Administration of nitric oxide (NO) alone remains ineffective in CDH cases. We investigated in near full-term lambs with and without CDH the role of guanylate cyclase (GC), the enzyme activated by NO in increasing cyclic 3'-5'-guanylosine monophosphate, and the role of phosphodiesterase (PDE) 5, the enzyme-degrading cyclic 3'-5'-guanylosine monophosphate. METHODS: Congenital diaphragmatic hernia was surgically created in fetal lambs at 85 days of gestation. Pulmonary hemodynamics were assessed by means of pressure and blood flow catheters (135 days). In vitro, we tested drugs on rings of isolated pulmonary vessels. RESULTS: In vivo, sodium nitroprusside, a direct NO donor, and methyl-2(4-aminophenyl)-1,2-dihydro-1-oxo-7-(2-pyridinylmethoxy)-4-(3,4,5 trimethoxyphenyl)-3-isoquinoline carboxylate sulfate (T-1032) and Zaprinast, both PDE 5 blockers, reduced pulmonary vascular resistance in CDH and non-CDH animals. The activation of GC by sodium nitroprusside and the inhibition of PDE 5 by T-1032 were less effective in CDH animals. In vitro, the stimulation of GC by 3(5'hydroxymethyl-2'furyl)-1-benzyl indazole (YC-1) (a benzyl indazole derivative) and the inhibition of PDE 5 by T-1032 were less effective in pulmonary vascular rings from CDH animals. The YC-1-induced vasodilation in rings from CDH animals was higher when associated with the PDE 5 inhibitor T-1032. CONCLUSIONS: Guanylate cyclase and PDE 5 play a role in controlling pulmonary vascular tone in fetal lambs with or without CDH. Both enzymes seem to be impaired in fetal lambs with CDH.

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PURPOSE: To investigate the ability of inversion recovery ON-resonant water suppression (IRON) in conjunction with P904 (superparamagnetic nanoparticles which consisting of a maghemite core coated with a low-molecular-weight amino-alcohol derivative of glucose) to perform steady-state equilibrium phase MR angiography (MRA) over a wide dose range. MATERIALS AND METHODS: Experiments were approved by the institutional animal care committee. Rabbits (n = 12) were imaged at baseline and serially after the administration of 10 incremental dosages of 0.57-5.7 mgFe/Kg P904. Conventional T1-weighted and IRON MRA were obtained on a clinical 1.5 Tesla (T) scanner to image the thoracic and abdominal aorta, and peripheral vessels. Contrast-to-noise ratios (CNR) and vessel sharpness were quantified. RESULTS: Using IRON MRA, CNR and vessel sharpness progressively increased with incremental dosages of the contrast agent P904, exhibiting constantly higher contrast values than T1 -weighted MRA over a very wide range of contrast agent doses (CNR of 18.8 ± 5.6 for IRON versus 11.1 ± 2.8 for T1 -weighted MRA at 1.71 mgFe/kg, P = 0.02 and 19.8 ± 5.9 for IRON versus -0.8 ± 1.4 for T1-weighted MRA at 3.99 mgFe/kg, P = 0.0002). Similar results were obtained for vessel sharpness in peripheral vessels, (Vessel sharpness of 46.76 ± 6.48% for IRON versus 33.20 ± 3.53% for T1-weighted MRA at 1.71 mgFe/Kg, P = 0.002, and of 48.66 ± 5.50% for IRON versus 19.00 ± 7.41% for T1-weighted MRA at 3.99 mgFe/Kg, P = 0.003). CONCLUSION: Our study suggests that quantitative CNR and vessel sharpness after the injection of P904 are consistently higher for IRON MRA when compared with conventional T1-weighted MRA. These findings apply for a wide range of contrast agent dosages.

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[eng] ISO standard 9001 is one of a set of management tools that libraries have adopted in recent years. This article focuses on libraries in higher education institutions that have received ISO certification of their quality management systems (ISO standard 9001:2000). We examine their reasons for seeking certification and the advantages and difficulties they have encountered in applying this ISO standard. Finally, we consider the future prospects of ISO standard 9001 in university libraries.

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The integration of specific institutions for teacher education into the higher education system represents a milestone in the Swiss educational policy and has broad implications. This thesis explores organizational and institutional change resulting from this policy reform, and attempts to assess structural change in terms of differentiation and convergence within the system of higher education. Key issues that are dealt with are, on the one hand, the adoption of a research function by the newly conceptualized institutions of teacher education, and on the other, the positioning of the new institutions within the higher education system. Drawing on actor-centred approaches to differentiation, this dissertation discusses system-level specificities of tertiarized teacher education and asks how this affects institutional configurations and actor constellations. On the basis of qualitative and quantitative empirical data, a comparative analysis has been carried out including case studies of four universities of teacher education as well as multivariate regression analysis of micro-level data on students' educational choices. The study finds that the process of system integration and adaption to the research function by the various institutions have unfolded differently depending on the institutional setting and the specific actor constellations. The new institutions have clearly made a strong push to position themselves as a new institutional type and to find their identity beyond the traditional binary divide which assigns the universities of teacher education to the college sector. Potential conflicts have been identified in divergent cognitive normative orientations and perceptions of researchers, teacher educators, policy-makers, teachers, and students as to the mission and role of the new type of higher education institution. - L'intégration dans le système d'enseignement supérieur d'institutions qui ont pour tâche spécifique de former des enseignants peut être considérée comme un événement majeur dans la politique éducative suisse, qui se trouve avoir des conséquences importantes à plusieurs niveaux. Cette thèse explore les changements organisationnels et institutionnels résultant de cette réforme politique, et elle se propose d'évaluer en termes de différentiation et de convergence les changements structurels intervenus dans le système d'éducation tertiaire. Les principaux aspects traités sont d'une part la nouvelle mission de recherche attribuée à ces institutions de formation pédagogique, et de l'autre la place par rapport aux autres institutions du système d'éducation tertiaire. Recourant à une approche centrée sur les acteurs pour étudier les processus de différen-tiation, la thèse met en lumière et en discussion les spécificités inhérentes au système tertiaire au sein duquel se joue la formation des enseignants nouvellement conçue et soulève la question des effets de cette nouvelle façon de former les enseignants sur les configurations institutionnelles et les constellations d'acteurs. Une analyse comparative a été réalisée sur la base de données qualitatives et quantitatives issues de quatre études de cas de hautes écoles pédagogiques et d'analyses de régression multiple de données de niveau micro concernant les choix de carrière des étudiants. Les résultats montrent à quel point le processus d'intégration dans le système et la nouvelle mission de recherche peuvent apparaître de manière différente selon le cadre institutionnel d'une école et la constellation spécifique des acteurs influents. A pu clairement être observée une forte aspiration des hautes écoles pédagogiques à se créer une identité au-delà de la structure binaire du système qui assigne la formation des enseignants au secteur des hautes écoles spéciali-sées. Des divergences apparaissent dans les conceptions et perceptions cognitives et normatives des cher-cheurs, formateurs, politiciens, enseignants et étudiants quant à la mission et au rôle de ce nouveau type de haute école. - Die Integration spezieller Institutionen für die Lehrerbildung ins Hochschulsystem stellt einen bedeutsamen Schritt mit weitreichenden Folgen in der Entwicklung des schweizerischen Bildungswesens dar. Diese Dissertation untersucht die mit der Neuerung verbundenen Veränderungen auf organisatorischer und institutioneller Ebene und versucht, die strukturelle Entwicklung unter den Gesichtspunkten von Differenzierung und Konvergenz innerhalb des tertiären Bildungssystems einzuordnen. Zentrale Themen sind dabei zum einen die Einführung von Forschung und Entwicklung als zusätzlichem Leistungsauftrag in der Lehrerbildung und zum andern die Positionierung der pädagogischen Hochschulen innerhalb des Hochschulsystems. Anhand akteurzentrierter Ansätze zur Differenzierung werden die Besonderheiten einer tertiarisierten Lehrerbildung hinsichtlich der Systemebenen diskutiert und Antworten auf die Frage gesucht, wie die Reform die institutionellen Konfigurationen und die Akteurkonstellationen beeinflusst. Auf der Grundlage qualitativer und quantitativer Daten wurde eine vergleichende Analyse durchgeführt, welche Fallstudien zu vier pädagogischen Hochschulen umfasst sowie Regressionsanalysen von Mikrodaten zur Studienwahl von Maturanden. Die Ergebnisse machen deutlich, dass sich der Prozess der Systemintegration und die Einführung von Forschung in die Lehrerbildung in Abhängigkeit von institutionellen Ordnungen und der jeweiligen Akteurkonstellation unterschiedlich gestalten. Es lässt sich bei den neu gegründeten pädagogischen Hochschulen ein starkes Bestreben feststellen, sich als neuen Hochschultypus zu positionieren und sich eine Identität zu schaffen jenseits der herkömmlichen binären Struktur, welche die pädagogischen Hochschulen dem Fachhochschul-Sektor zuordnet. Potentielle Konflikte zeichnen sich ab in den divergierenden kognitiven und normativen Orientierungen und Wahrnehmungen von Forschern, Ausbildern, Bildungspolitikern, Lehrern und Studierenden hinsichtlich des Auftrags und der Rolle dieses neuen Typs Hochschule.

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OBJECTIVE: Overanticoagulated medical inpatients may be particularly prone to bleeding complications. Among medical inpatients with excessive oral anticoagulation (AC), we sought to identify patient and treatment factors associated with bleeding. METHODS: We prospectively identified consecutive patients receiving oral AC admitted to the medical ward of a university hospital (February-July 2006) who had at least one international normalized ratio (INR) value >3.0 during the hospital stay. We recorded patient characteristics, AC-related factors, and concomitant treatments (e.g., platelet inhibitors) that increase the bleeding risk. The outcome was overall bleeding, defined as the occurrence of major or minor bleeding during the hospital stay. We used logistic regression to explore patient and treatment factors associated with bleeding. RESULTS: Overall, 145 inpatients with excessive oral AC comprised our study sample. Atrial fibrillation (59%) and venous thromboembolism (28%) were the most common indications for AC. Twelve patients (8.3%) experienced a bleeding event. Of these, 8 had major bleeding. Women had a somewhat higher risk of major bleeding than men (12.5% vs 4.1%, p = 0.08). Multivariable analysis demonstrated that female gender was independently associated with bleeding (odds ratio [OR] 4.3, 95% confidence interval [95% C1] 1.1-17.8). Age, history of major bleeding, value of the index INR, and concomitant treatment with platelet inhibitors were not independent predictors of bleeding. CONCLUSIONS: We found that hospitalized women experiencing an episode of excessive oral AC have a 4-fold increased risk of bleeding compared with men. Whether overanticoagulated women require more aggressive measures of AC reversal must be examined in further studies.

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We extend the partial resummation technique of Fokker-Planck terms for multivariable stochastic differential equations with colored noise. As an example, a model system of a Brownian particle with colored noise is studied. We prove that the asymmetric behavior found in analog simulations is due to higher-order terms which are left out in that technique. On the contrary, the systematic ¿-expansion approach can explain the analog results.