331 research outputs found
"In seiner Blüte bleicht mein Leben" : Magda Spiegel – Schicksal einer jüdischen Künstlerin zwischen Kaiserreich und Nationalsozialismus
Rezension zu: Claudia Becker : Magda Spiegel : Biographie einer Frankfurter Opernsängerin ; 1887 – 1944 ; Studien zur Frankfurter Geschichte, Band 52 (Hrsg. Dieter Rebentisch), Waldemar Kramer-Verlag, Frankfurt 2003, ISBN 3-7829-0547-4, 263 Seiten, 29,80 Euro
Machtpoker am Main: "Der Braune Magistrat" : Studie zur Kommunalpolitik während des Nationalsozialismus
Rezension zu: Bettina Tüffers : Der Braune Magistrat : Personalstruktur und Machtverhältnisse in der Frankfurter Stadtregierung 1933 – 1945. Studien zur Frankfurter Geschichte, Band 54 (Hrsg. Dieter Rebentisch), Waldemar Kramer Verlag 2004, ISBN 3-7829-0558-X, 368 Seiten, 34,80 Eur
"Berlin im Licht?" Frankfurt im Licht! : Spaziergang durch die Vergnügungsstätten der Zwanziger Jahre
Rezension zu: Oliver M. Piecha : Roaring Frankfurt : Mit Siegfried Kracauer ins Schumanntheater. Verlag Edition AV, Frankfurt 2005, ISBN 3-936049-48-3, 189 Seiten, 17 Euro
Transcriptional Regulation of N-Acetylglutamate Synthase and its Clinical Relevance
The urea cycle converts ammonia, the toxic byproduct of protein metabolism, to non-toxic urea utilizing six enzymes in mammalian liver hepatocytes. In the mitochondria, the enzyme N-acetylglutamate synthase (NAGS), produces the essential allosteric activator, N-acetylglutamate (NAG), for the first enzyme of the cycle, carbamylphosphate synthetase 1 (CPS1). Ammonia sequestered by CPS1 is condensed with bicarbonate and phosphate from ATP to produce to carbamylphosphate, which is then condensed with ornithine to produce citrulline by ornithine transcarbamylase (OTC). Citrulline is then transported to the cytoplasm where it is further converted by the distal urea cycle enzymes argininosuccinate synthetase, argininosuccinate lyase, and arginase 1 to the end product, urea.
Prior to sequestration of ammonia, signaling pathways sense dietary protein load. Analysis was conducted to determine the effect of protein composition on metabolic signaling and nutrient sensing pathways AMPK, mTOR, and eIF2, promote transcriptional activation of urea cycle genes and translation of urea cycle proteins. Future studies will determine the importance of these pathways on the urea cycle and whether post-translational control mechanisms, such as phosphorylation, also respond to protein in the diet.
Since NAGS plays an important role in controlling the rate of urea production by activating the rate limiting CPS1, its regulatory mechanisms control ureagenesis flux. This project elucidated the regulatory domains of NAGS including a promoter which contains multiple tissue- and species- specific transcription initiation sites and binding sites for transcription factors CREB and Sp1. It also found and characterized an enhancer 3kb upstream of the translational start site which confers liver specificity and has binding sites for NF-Y and HNF-1. These transcription factors are regulated by glucocorticoid and glucagon hormone signaling pathways and are also regulated in a tissue selective manner.
A deficiency of NAGS in humans and mice leads to high ammonia, low urea, and high glutamine levels in the plasma, and can be overcome by treatment with N-carbamylglutamate (NCG). This project identified a patient with NAGS deficiency and hyperammonemia caused by a deleterious mutation in the HNF-1 binding site within the enhancer of the NAGS gene, which was identified and characterized by this research. This mutation caused decreased transcription of NAGS due to reduced HNF-1 binding. Subsequently, this work found disease-causing mutations in the promoter region of OTC which have been shown to interfere with HNF-4 binding.
The knowledge garnered by this project significantly increases our understanding of the regulation of urea cycle RNA and protein expression and their role in disease pathophysiology. Understanding of these mechanisms will lead to improved diagnoses and continued development of effective treatments for people with urea cycle disorders and hyperammonemia
Standing Rock, the Sioux Treaties, and the Limits of the Supremacy Clause
The controversy surrounding the Dakota Access Pipeline (“DAPL”) has put the peaceful plains of North Dakota in the national and international spotlight, drawing thousands of people to the confluence of the Missouri and Cannonball Rivers outside of Standing Rock Sioux Reservation for prayer and peaceful protest in defense of the Sioux Tribes’ treaties, lands, cultural property, and waters. Spanning over 7 months, including the harsh North Dakota winter, the gathering was visited by indigenous leaders and communities from around the world and represents arguably the largest gathering of indigenous peoples in the United States in more than 100 years.
At the center of the fight are the 1851 and 1868 Treaties entered into by the United States and the Great Sioux Nation. The pipeline route, which was chosen without input from the Tribes, runs directly through the heart of treaty lands secured to the Great Sioux Nation in the 1851 Treaty of Fort Laramie, lands to which the Sioux Tribes continue to have strong cultural, spiritual, and historical ties. Furthermore, the construction and operation of an oil pipeline directly upstream from their current reservations undoubtedly threatens the Tribes’ hunting and fishing rights expressly reserved in the 1868 Treaty and affirmed in numerous subsequent Acts of Congress, as well as their reserved water rights pursuant to the Winters Doctrine.
But as the Tribe and their attorneys battled for injunctive relief in federal court, the Treaties were largely absent in the pleadings and court opinions. However, with the District Court’s ruling on June 14, 2017, it appears the Treaties now present the crux of the surviving argument, presenting problems for the Court in terms of both their applicability in the face of Congress’ plenary power over Indian tribes and diminished Trust responsibility as well as the appropriate remedy for the Tribes when and if these Treaty rights are violated. As such, the case provides an opportunity to analyze the truth and lies surrounding the Constitutional place of Indian Treaties in federal courts.
Article VI, Clause 2 of the Constitution states “all Treaties made, or which shall be made, under the Authority of the United States, shall be the supreme Law of the Land; and the Judges in every State shall be bound thereby, any Thing in the Constitution or Laws of any state to the Contrary notwithstanding.” Known as the “Supremacy Clause,” this constitutional provision has serious implications in federal Indian law. Of particular importance is whether treaties made with Indian tribes can be considered the “Supreme Law of the Land”. The current litigation and historic indigenous uprising against the Dakota Access Pipeline, the route of which lies within recognized tribal treaty boundaries, provides a contemporary example of the limitations of Supremacy Clause. This article attempts to place the Standing Rock and other Sioux Tribes’ legal battle against the Dakota Access pipeline against the history of Indian treaties and treaty rights for a contemporary examination of federal courts application of Indian treaty rights and the limits of the Supremacy Clause to ensure Indian treaties and treaty rights be respected as the “Supreme Law of the Land
Standing Rock, the Sioux Treaties, and the Limits of the Supremacy Clause
The controversy surrounding the Dakota Access Pipeline (“DAPL”) has put the peaceful plains of North Dakota in the national and international spotlight, drawing thousands of people to the confluence of the Missouri and Cannonball Rivers outside of Standing Rock Sioux Reservation for prayer and peaceful protest in defense of the Sioux Tribes’ treaties, lands, cultural property, and waters. Spanning over 7 months, including the harsh North Dakota winter, the gathering was visited by indigenous leaders and communities from around the world and represents arguably the largest gathering of indigenous peoples in the United States in more than 100 years.
At the center of the fight are the 1851 and 1868 Treaties entered into by the United States and the Great Sioux Nation. The pipeline route, which was chosen without input from the Tribes, runs directly through the heart of treaty lands secured to the Great Sioux Nation in the 1851 Treaty of Fort Laramie, lands to which the Sioux Tribes continue to have strong cultural, spiritual, and historical ties. Furthermore, the construction and operation of an oil pipeline directly upstream from their current reservations undoubtedly threatens the Tribes’ hunting and fishing rights expressly reserved in the 1868 Treaty and affirmed in numerous subsequent Acts of Congress, as well as their reserved water rights pursuant to the Winters Doctrine.
But as the Tribe and their attorneys battled for injunctive relief in federal court, the Treaties were largely absent in the pleadings and court opinions. However, with the District Court’s ruling on June 14, 2017, it appears the Treaties now present the crux of the surviving argument, presenting problems for the Court in terms of both their applicability in the face of Congress’ plenary power over Indian tribes and diminished Trust responsibility as well as the appropriate remedy for the Tribes when and if these Treaty rights are violated. As such, the case provides an opportunity to analyze the truth and lies surrounding the Constitutional place of Indian Treaties in federal courts.
Article VI, Clause 2 of the Constitution states “all Treaties made, or which shall be made, under the Authority of the United States, shall be the supreme Law of the Land; and the Judges in every State shall be bound thereby, any Thing in the Constitution or Laws of any state to the Contrary notwithstanding.” Known as the “Supremacy Clause,” this constitutional provision has serious implications in federal Indian law. Of particular importance is whether treaties made with Indian tribes can be considered the “Supreme Law of the Land”. The current litigation and historic indigenous uprising against the Dakota Access Pipeline, the route of which lies within recognized tribal treaty boundaries, provides a contemporary example of the limitations of Supremacy Clause. This article attempts to place the Standing Rock and other Sioux Tribes’ legal battle against the Dakota Access pipeline against the history of Indian treaties and treaty rights for a contemporary examination of federal courts application of Indian treaty rights and the limits of the Supremacy Clause to ensure Indian treaties and treaty rights be respected as the “Supreme Law of the Land
The Impact of An Online Learning Credit Recovery Program on the Graduation Rate of Students Receiving Free and Reduced Meals
Low-income students are five times more likely to drop out of high school than their high-income peers (Chapman, Laird, Ifill, & KewalRamani, 2011). While race, geography, economic conditions, access to high quality teachers, gender, and age are measures often used to determine if a student is likely to drop out of school, economic conditions are the single variable that most closely predicts dropout potential (Mid-Atlantic State Department of Education). As an intervention tool, “online coursework may lead to increased self-efficacy in at-risk students if adequate supports are in place to help them to succeed” (Lewis, Whiteside, and Dikkers, 2014). According to Lips (2010), “Online learning could address many discrepancies in American education in terms of the disparate access to high-quality teachers and instruction caused by socioeconomic and geographic differences” (p. 4). Describing the impact of online learning on at risk students, Archambault et al. (2010) said, “Virtual school programs find that taking advantages of the technology, various curriculum programs and being able to individualize instruction are effective strategies for meeting the needs of at-risk students” (p. 7). The purpose of this study was to examine the impact of an online learning credit recovery program on the graduation rates of students receiving free and reduced meal benefits at a high school in the Great Lakes Public Schools (a pseudonym) located in Mid-Atlantic State. The study compared the graduation rates of FARMS students who participated in the APEX online learning program against FARMS students who did not participate in the program. The results failed to reject the null hypothesis indicating that there was no statistical difference between the two groups. This study may be useful as the district seeks to evaluate the effectiveness of its intervention programs for struggling students
Schädigung und Versagensverhalten hochfester Mehrphasenstähle
Hochfeste Mehrphasenstähle sind im modernen Karosseriebau unabdingbar für Stoffleichtbau und Verbesserung der Crashperformance. Die höheren Festigkeiten gehen mit einer reduzierten Duktilität einher. Insbesondere die heterogene Mikrostruktur von Dualphasenstählen neigt zur Schädigungsevolution und beeinflusst das Formänderungsvermögen. Ziel dieser Dissertation ist eine Verbesserung des Verständnisses des Schädigungs- und Versagensverhaltens hochfester Mehrphasenstähle zur Werkstoffoptimierung und zur sicheren Handhabung dieser Werkstoffe im Umformprozess und der Umformsimulation.
Das Werkstoffportfolio aus Dual- und Komplexphasenstähle erlaubt die dezidierte Analyse der Schädigungsevolution mittels Licht- und Rasterelektronenmikroskopie. So findet in einer ferritischen Matrix mit eingelagerten Martensitinseln und größeren Ferritkörnern bei geringer Härtedifferenz zwischen den Phasen bevorzugt eine Ferrit-Martensitdekohäsion statt. Eine höhere Martensithärte, Martensitzeilen und eine heterogene Martensitverteilung begünstigen die Schädigungsevolution und reduzieren die ertragbaren Dehnungen. Die Komplexphasenstähle zeigen, dass eine homogenere Mikrostruktur zu einer hohen Schädigungstoleranz und hohen lokal ertragbaren Dehnungen führt. Die Schädigungsevolution in den untersuchten Mehrphasenstählen führt zu Porositäten im niedrigen Prozentbereich.
Mit Hilfe der Anwendung des erweiterten Lemaitre-Modells wird für Dual- und Complexphasenstähle gezeigt, dass dementsprechend eine Berücksichtigung der mikrostrukturellen Schädigung durch Poren im Sinne einer Reduktion des tragenden Querschnitts auf makroskopischer Skala in der Blechumformsimulation nicht notwendig ist. Zur Verbesserung der Versagensprognose eignen sich Modellbruchkurven invers kalibrierter Schädigungsmodelle oder Bruchkriterien. Am Beispiel der FFL/SFFL wird ersichtlich, dass eine Anwendung von Werkstoffbruchkurven ohne Berücksichtigung der Netzabhängigkeit für die Blechumformsimulation nicht sinnvoll ist. Werkstoffe können anhand dieser Bruchkurven jedoch voneinander differenziert werden.
Aus der FFL/SFFL abgeleitet wird die wahre Dickendehnung bei Bruch folglich als Maß zur Charakterisierung des Formänderungsvermögens und damit einhergehend der Schädigungstoleranz qualifiziert. Hiermit können zudem Kantenrissempfindlichkeit, Bruchzähigkeit und Biegbarkeit hochfester Mehrphasenstähle abgeschätzt werden. Zusammen mit der wahren Gleichmaßdehnung wird die Bewertung des duktilen Schädigungs- und Versagensverhaltens ermöglicht. Beide Maße zusammen bilden die relevanten mikrostrukturellen Charakteristika hochfester Mehrphasenstähle auf makroskopischer Skala ab und können als sinnvolle Größen für die produktionsbegleitende Prüfung, zielgerichtete Entwicklung neuer Werkstoffe sowie für die produkt- und prozessgerechte Werkstoffauswahl im Entwicklungsprozess genutzt werden.High-strength multiphase steels are essential in modern car-body manufacture for lightweight design as well as improved crash performance. The higher strength is accompanied by a lower ductility. In particular, the heterogeneous microstructure of dual-phase steels tends to damage evolution and influences the plastic deformation capacity. The aim of this thesis is to improve the understanding of the damage and failure behavior of high-strength multiphase steels for material optimization and safe handling of these materials in forming processes and forming simulation.
The material portfolio of dual- and complex-phase steels allows the decided analysis of damage evolution by light and scanning electron microscopy. In a ferritic matrix with embedded martensite islands, larger ferrite grains and with a small difference in hardness, ferrite-martensite decohesion occurs predominantly. Higher martensite hardness, martensite rows and a heterogeneous martensite distribution favor damage evolution and reduce the bearable strains. The complex-phase steels show that a homogeneous microstructure leads to a high damage tolerance and high locally bearable strains. Damage evolution in the investigated multiphase steels results in porosities in the low percentage range.
It is shown with the help of the extended Lemaitre model that a consideration of the microstructural damage effects in the sense of a reduction of the load bearing cross-section is thus not necessary in sheet metal forming simulation on a macroscopic scale. To improve failure assessment, the application of model fracture curves of inversely calibrated damage models or fracture criteria is suitable. The example of FFL/SFFL calibrated with the direct method shows that the application of material fracture curves without consideration of mesh dependency is not useful for sheet metal forming simulation. However, materials can be differentiated from each other on the basis of these fracture curves.
The true thickness strain at fracture derived from FFL/SFFL is therefore qualified as a suitable measure for the determination of the plastic deformation capacity and thus the damage tolerance. In addition, edge crack sensitivity and bendability of high-strength multiphase steels can be estimated. Together with the true uniform strain as a measure, the assessment of the ductility and the ductile damage and failure behavior is possible. Both measures represent together the relevant microstructural characteristics on a macroscopic scale and can be used for testing during production, targeted development of new materials and for product- and process-oriented material selection in the development process
Efeito do consumo de Tucum-do-cerrado (Bactris setosa Mart.) no metabolismo de carboidratos
Dissertação (mestrado)—Universidade de Brasília, Faculdade de Ciências da Saúde, Departamento de Nutrição, Programa de Pós-Graduação em Nutrição Humana, 2017.Compostos bioativos dietéticos podem melhorar a homeostase de glicose ao passo que a ingestão de ferro pode prejudicar a regulação do metabolismo de glicose e resposas insulinêmicas. Este estudo investigou o efeito do consumo de tucum-do-cerrado (Bactris setosa Mart.) no metabolismo de carboidratos e a resposta redox em ratos suplementados ou não com ferro dietético. Ratos wistar machos foram tratados com uma das seguintes dietas: CT: dieta controle (AIN-93G); + Fe: dieta enriquecida com ferro; Tuc: dieta controle + 15% de tucumdo-cerrado ou Tuc + Fe: dieta enriquecida com ferro + 15% de tucum-do-cerrado. A suplementação de ferro aumentou a peroxidação lipídica e os níveis de proteínas carboniladas no músculo esquelético. Além disso, a suplementação do metal provocou aumento na atividade hepática de glicoquinase e fosfofrutoquinase. Por outro lado, houve redução de glicose-6fosfatase e nos níveis de diversos transcritos Scl2a2 (intestino), Slc2a4 (músculo) e Prkaa2 α (músculo). A ingestão de tucum-do-cerrado aumentou a expressão hepática de Slc2ac, Prkaa1 α e Prkaa2 α, mas reduziu a atividade de G6pase. No intestino, o fruto diminuiu os níveis de Slc5a1 ao passo que causou o mesmo efeito nos genes Slc2a4 e Prkaa2 α no músculo esquelético em relação ao controle. A associação entre ingestão de tucum-do-cerrado e suplementação de ferro aumentou a transcrição de Prkaa1 α e Pck1, comparado aos grupos controle e Fe+, ao passo que os níveis de Slc2a2 foram aumentados em relação ao grupo com ingestão aumentada de ferro. O co-tratamento também reduziu a atividade hepática de G6pase em relação a todos os grupos. Não houveram diferenças estatísticas no peso, ingestão alimentar, eficiência energética, glicemia e insulinemia em jejum. Em conjunto, os resultados sugerem que a ingestão de tucumdo-cerrado pode induzir modulação da expressão de Prkaa1 α e Prkaa2 α, podendo inbir assim enzimas-chave da gliconeogenese como a G6Pase e a PEPCK, além de favorecer a captação de glicose por meio da regulação de GLUT 2 no fígado. Além disso, a suplementação moderada de ferro parece promever estímulo a enzimas relacionadas a glicólise, como a GK e a PFK1, inibindo enzimas gliconeogênicas como a G6Pase e PEPCK.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq).Dietary phytochemicals may improve glucose metabolism while iron excess seems to be associated to impaired glucose homeostasis and insulin responses. This study investigated the effect of tucum-do-cerrado (Bactris setosa Mart.) consumption on the carbohydrate metabolism and redox response in rats supplemented or not with dietary iron. Male wistar rats were treated with one of the following diets: CT: control diet (AIN-93G); +Fe: iron-enriched diet; Tuc: control diet + 15% tucum-do-cerrado or Tuc+Fe: iron-enriched diet + 15% tucum-do-cerrado. Iron supplementation increased muscle lipid and protein oxidation, hepatic glucokinase (GK) and phosphofrutokinase 1 (PFK1) activities and decreased hepatic glucose-6-phosphatase (G6Pase), intestinal Scl2a2 and muscle Slc2a4 and Prkaa2α mRNA levels compared to CT group. Tucum-do-cerrado consumption (Tuc) increased hepatic Slc2a2, Prkaa1α, Prkaa2α and intestinal Slc5a1 mRNA levels, also decreased hepatic G6Pase activity, muscle Slc2a4 and Prkaa2α in relation to CT group. The association of tucum-do-cerrado with iron-enriched diet increased hepatic Prkaa1 and Pck1 compared to the CT and +Fe groups, intestinal Slc2a2 mRNA levels compared to the +Fe group, while decreased hepatic G6Pase activity in relation to the CT, +Fe and Tuc+Fe groups and muscle Slc2a4 and Prkaa2α compared to CT group. These results sugest that tucum-do-cerrado consumption might induce Prkaa1α and Prkaa2α expression, which may inhibit gluconeogenic rate limiting enzymes, G6Pase and PEPCK and upregulates GLUT2 hepatic glucose uptake. In addition, moderate iron supplementation improves intracellular hepatic glucose response, stimulating the glycolytic rate limiting enzymes GK and PFK1 while inhibiting gluconeogenic enzymes G6Pase and PEPCK
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