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Against the backdrop of a growing national and international accountability movement in education outcomes, this study sets up a simple model of yardstick competition with incumbent-disciplining effects through voters comparing performance measures of public education both across nations and federal states. It implies a potential strategic dilemma where a single top-performance state can block reform measures that could benefit low-performance states more than would do for itself. The linchpin predictions of the model are tested by analyzing announcement effects of student achievement tests on vote and popularity (VP) functions of German national and state government incumbents.

The detection of oxidative stress markers has gained increasing importancy in the early investigation of diseases like diabetes, cancer or hypertension. 8 oxo 2' deoxyguanosine (8-oxodG) is the main marker, which is used for the intracellular detection of oxidative stress levels. However, the oxidative stress markers 8 oxoguanine (8-oxoGua), a product of the DNA base excision repair and 8 oxoguanosine (8-oxoGuo), a marker for oxidative damaged RNA have received less attention up to now. The renin-angiotensin-aldosterone system (RAAS) plays an important role in the regulation processes of the blood pressure system. During hypertension angiotensin II (Ang II) and aldosterone (Aldo) are released in high concentrations over a longer period leading to non-physiological effects of the RAAS hormones. Subsequently, an increase of the intracellular oxidative stress level in kidney cells can be measured. The aim of this thesis is the in vitro and in vivo detection of the oxidative damage in DNA and RNA by measuring oxidative stress markers, especially 8-oxodG which is triggered by Ang II and Aldo. In vitro experiments were carried out in LLC-PK1, a cell line originated from porcine kidney cells. It could been shown that Ang II and Aldo led to a dose-dependent increase of DNA damage in the cells. A time-dependent increase was detected for the first 30 minutes of the treatment. For the rest of the experimental set up (4 h) the level of detected DNA damage remained constant. The FPG comet assay and the immunocytochemical staining showed a significant increase of 8-oxodG in the cells, whereas the HPLC-MS/MS measurement only detected a small increase of 8-oxodG in the DNA. The FPG enzyme, which recognises also other oxidized purines besides 8-oxodG, which led to an overestimation of 8-oxodG in the comet assay. Also, the 8 oxodG antibody, which was used in the immunocytochemical analysis, detected higher amounts of 8-oxodG most likely due to its side reactions with other oxidized DNA structures. One of the main advantages of the last mentioned methods is the direct measurement in damaged cells, whereas the HPLC-MS/MS requires an isolation of the DNA. During this isolation process the oxidative stress markers can be oxidized and the detection can become imprecise. The main purpose of the in vivo experiments was the detection of the oxidative stress marker 8-oxoGua, 8-oxodG and 8-oxoGuo in the urine of test animals. The treatment of C57BL/6 mice and Sprague Dawley (SD) rats with the RAAS hormones led to an increase of the blood pressure, higher DNA damage due to oxidative stress as well as an increased excretion rate of oxidative stress markers. The inhibition of the angiotensin II type 1- or mineralocorticoid receptor and a mutation of the AT1a gene could show, that the DNA damage is independent from the hypertension. In addition, it was shown that the NOX4 is not alone responsible for the oxidative stress. Other NADPH oxidases must contribute to the induction of oxidative stress inside the cell. Moreover, the activation of the Nrf2 pathway has an influence on the effect of Aldo in SD rats. The excretion rate of the oxidative stress markers in the 20 h urine of the treated animals showed how the equilibrium between the DNA repair and the oxidative stress level was changing over time. The measurement of 8-oxoGuo became more and more popular, because up to the fact that 80 % of the DNA is translated into RNA. Overall, the detection of 8-oxodG and 8-oxoGuo is feasible for monitoring the disease or the healing process, because the measurement is non-invasive. The detection of 8-oxodG and 8-oxoGuo in nucleic acids is a first step into the field of basic research methods, because it reveals a snapshot of the nucleic acid damage in the cell at a specific time point. Usually, there will be an overestimation of the oxidative stress marker resulting from the analytical method. Although, it is possible to detect an underestimation of oxidative stress markers in tissue samples if not all cell types are damaged equally. Therefore, a primary goal should be the detection of a stable oxidation product of guanine to insure a reliable detection strategy and for a better understanding of the equilibrium of DNA oxidation and repair., Der Nachweis von oxidativen Stressmarkern hat bei der Untersuchung von Krankheiten wie Diabetes, Krebs und Hypertonie an großer Bedeutung gewonnen. Vor allem 8-Oxo-2’-desoxyguanosin (8-oxodG) wird gezielt mit verschiedenen Methoden gemessen und als Marker für oxidativen Stress herangezogen. Daneben haben 8 Oxoguanin (8-oxoGua), als Produkt aus der Basenexzisionsreparatur der DNA, sowie 8-Oxoguanosin (8-oxoGuo), als Biomarker für oxidativ geschädigte RNA, bisher weniger Aufmerksamkeit bekommen. Das Renin-Angiotensin Aldosteron System (RAAS) spielt eine wichtige Rolle in der Regulierung des Blutdrucks. Im Falle einer Hypertonie werden Angiotensin II (Ang II) und Aldosteron (Aldo) über einen langen Zeitraum in erhöhter Konzentration ausgeschüttet. Dieser Umstand bewirkt eine nicht physiologische Wirkung der Hormone des RAAS, welche zu einer Induktion von oxidativem Stress führt. Die Zielsetzung dieser Arbeit ist es, die oxidative Schädigung, ausgelöst durch Ang II und Aldo, in der DNA und der RNA in vitro und in vivo nachzuweisen und dabei speziell den Biomarker 8-oxodG zu untersuchen. In-vitro-Experimente wurden mit LLC PK1-Zellen, einer Schweinenierenzelllinie, durchgeführt. Ang II und Aldo lösten einen dosisabhängigen Anstieg der DNA Schäden in LLC PK1 Zellen aus. Eine Zeitabhängigkeit wurde für die ersten 30 Minuten gezeigt. Für die restliche Zeit (4 h) blieb der nachgewiesene DNA Schaden konstant. Der FPG Comet-Assay und die immunzytochemische Färbung zeigten jeweils eine signifikante Zunahme von 8-oxodG in LLC-PK1-Zellen an, während die HPLC MS/MS Messung nur geringe Veränderungen nachwies. Das FPG Enzym erkennt neben 8-oxodG auch andere oxidierte Purine und sorgte so für eine Überbestimmung des DNA-Schadens. Bei der immunzytochemischen Färbung entsteht die Überbestimmung durch Kreuzreaktionen des 8 oxodG Antikörpers mit oxidierten Strukturen in der DNA. Der Vorteil beider Analysemethoden ist die direkte Messung von Schädigungen in der Zelle, während die HPLC-MS/MS eine Isolierung der Nukleinsäuren voraussetzt. Bei diesem Schritt kann es zur Oxidation der Marker für oxidativen Stress kommen, welche einen genauen Nachweis erschwert. In vivo-Versuche hatten zum Ziel, die oxidativen Stressmarker 8-oxoGua, 8-oxodG und 8-oxoGuo im Urin nachzuweisen. Die Behandlung der C57BL/6-Mäuse und Sprague Dawley-Ratten (SD-Ratten) mit den Hormonen des RAAS zeigten einen Anstieg des Blutdrucks, erhöhte DNA Schäden durch oxidativen Stress sowie erhöhte Exkretionsraten der oxidativen Stressmarker. Durch eine Inhibierung des Angiotensin II-Typ1- oder Mineralkortikoidrezeptors sowie die Mutation des Gens AT1a konnte gezeigt werden, dass die Schädigungen unabhängig vom Blutdruck sind. Zudem konnte gezeigt werden, dass neben NOX4 auch andere NADPH Oxidasen für den oxidativen Stress verantwortlich sein müssen. Eine Aktivierung des Nrf2 Signalweges in den SD-Ratten hat Einfluss auf die Wirkung von Aldo. Die Exkretionsrate der oxidativen Biomarker im 20-h-Urin der behandelten Tiere zeigen, wie sich das Gleichgewicht zwischen DNA-Reparatur und oxidativem Stress verändert. Da 80 % der DNA in RNA umgeschrieben werden, ist der Nachweis von 8 oxoGuo in den Fokus gerückt. In der praktischen Anwendung kann mit der Messung von 8 oxodG und 8-oxoGuo ein Krankheits- oder Heilungsprozess auf nicht invasive Weise verfolgt werden. Der Nachweis von 8-oxodG und 8-oxoGuo in den Nukleinsäuren stellt einen Einstieg für die Grundlagenforschung dar, da sie nur eine Momentaufnahme der Nukleinsäureschädigung in der Zelle zeigen. Meist findet eine Überbestimmung, ausgelöst durch die Messmethode, statt. In Gewebeproben kann eine Unterbestimmung vorliegen, falls nicht alle Zelltypen vom oxidativen Stress betroffen sind. Daher sollte es ein vorrangiges Ziel sein, ein stabileres Oxidationsprodukt des Guanins nachzuweisen, um das Gleichgewicht der DNA-Oxidation und Reparatur besser zu verstehen.

Background: Although different prognostic factors for patients with renal cell carcinoma (RCC) and vena cava tumor thrombus (TT) have been studied, the prognostic value of histologic subtype in these patients remains unclear. Objective: We analyzed the impact of histologic subtype on cancer- specific survival (CSS). Design, settings, and participants: We retrospectively analyzed the records of 1774 patients with RCC and TT who underwent radical nephrectomy and tumor thrombectomy from 1971 to 2012 at 22 US and European centers. Outcome measurements and statistical analysis: Multivariable ordered logistic and Cox regression models were used to quantify the impact of tumor histology on CSS. Results and limitations: Overall 5- yr CSS was 53.4% (confidence interval [CI], 50.5- 56.2) in the entire group. TT level (according to the Mayo classification of macroscopic venous invasioninRCC) was I in38.5% ofpatients, II in30.6%, III in17.3%, andIV in13.5%. Histologic subtypes were clear cell renal cell carcinoma (cRCC) in 89.9% of patients, papillary renal cell carcinoma(pRCC) in 8.5%, and chromophobe RCC in 1.6%. In univariable analysis, pRCC was associated with a significantly worse CSS (p < 0.001) compared with cRCC. In multivariable analysis, the presence of pRCC was independently associated with CSS (hazard ratio: 1.62; CI, 1.01- 2.61; p < 0.05). Higher TT level, positive lymph node status, distant metastasis, and fat invasion were also independently associated with CSS. Conclusions: In our multi- institutional series, we found that patients with pRCC and vena cava TT who underwent radical nephrectomy and tumor thrombectomy had significantly worse ca ncer- specific outcomes when compared with patients with other histologic subtypes of RCC. We confirmed that higher TT level and fat invasion were independently associated with reduced CSS. (C) 2013 European Association of Urology. Published by Elsevier B. V. All rights reserved.

The thesis deals with five different human capital-related problems and tries to approach these problems from an empirical point of view. Each essay includes an own introduction and a short conclusion. All parts of the thesis are self-contained and can be read separately. The first essay entitled \"Size matters. The Relevance and Hicksian Surplus of Preferred College Class Size\" deals with the impact of class size on student evaluations of instructor performance using a sample of approximately 1,400 economics classes held at the university of Munich. Secondly, the data of a representative survey is used to estimate the willinngness-to-pay for preferred class size. Based on these findings and data, we try to give some evidence on what factors determine students\'' preferences for small class size with special interest to gender differences in the second essay entitled \"What determines Students Preferences for Small Class Size\". \"Total Instructional Time Exposure and Student Achievement: An Extreme Bound Analysis based on German state-level variation\" mainly deals with instructional time shortfall and student performance variation over the different German states using extreme bound analysis. Thereby the techniques also overcomes an error-in-variables problem and implied misinterpretation of existing studies that disregard the fact of learning being a cumulative process by relying on rather poor proxies for instructional time. In the essay \"No State Left Behind? Public education, accountability, and hybrid forms of federal governance\" the focus lies on announcement effects of the respective PISA results on election polls of federal government and federal states in Germany with regard to differences in relative performance in German states. In consideration of the results, we draw a policy conclusion about the distribution of authorities in a public education system between a federal government and federal states. Finally the last essay entitled \"A Re-examination of the Role of Gender in Determining Digital Piracy Behavior\" concentrates on the gender-gap in determining digital piracy behavior using a representative survey with more than 200 participants. In contrast to existing studies, we sharply discriminate between the frequency and the extent of pirating digital media.

Using pooled data on instructional time and student performance by subject, our study finds evidence for the school inputs-student achievement relationship for German states. This finding is robust both to the inclusion of state fixed effects and in an extensive extreme bounds analysis. It stands in contrast to the majority of related studies. We argue that this is due to an error-in-variables problem and implied misinterpretation of existing studies that disregard the fact of learning being a cumulative process by relying on rather poor proxies for instructional time. Highschool ninth graders from the OECD Programme of International Student Assessment (PISA-E) tests' bottom percentiles bene.t most from extra-instructional time measured in cumulated form from first up to ninth grade. Besides total instructional time exposure, we identify eight further social environment and institutional variables with robust impact on student performance. In contrast to instructional time hardly any of these factors can be affected by policy in the short run.