Design and Test of a Student Hybrid Rocket Engine with an External Carbon Fiber Composite Structure

The development of hybrid rockets offers excellent opportunities for the practical education of students at universities due to the high safety and relatively low complexity of the rocket propulsion system. During the German educational program Studentische Experimental-Raketen (STERN), students of the Technische Universität Braunschweig obtain the possibility to design and launch a sounding rocket with a hybrid engine. The design of the engine HYDRA 4X (HYbridDemonstrations-RaketenAntrieb) is presented, and the results of the first engine tests are discussed. The results for measured regression rates are compared to the results from the literature. Furthermore, the impact of the lightweight casing material carbon fiber-reinforced plastic (CFRP) on the hybrid engine mass and flight apogee altitude is examined for rockets with different total impulse classes (10 to 50 kNs). It is shown that the benefit of a lightweight casing material on engine mass decreases with an increasing total impulse. However, a higher gain on apogee altitude, especially for bigger rockets with a comparable high total impulse, is shown

Disease Evolution and Response to Rapamycin in Activated Phosphoinositide 3-Kinase δ Syndrome: The European Society for Immunodeficiencies-Activated Phosphoinositide 3-Kinase δ Syndrome Registry

Activated phosphoinositide 3-kinase (PI3K) δ Syndrome (APDS), caused by autosomal dominant mutations in PIK3CD (APDS1) or PIK3R1 (APDS2), is a heterogeneous primary immunodeficiency. While initial cohort-descriptions summarized the spectrum of clinical and immunological manifestations, questions about long-term disease evolution and response to therapy remain. The prospective European Society for Immunodeficiencies (ESID)-APDS registry aims to characterize the disease course, identify outcome predictors, and evaluate treatment responses. So far, 77 patients have been recruited (51 APDS1, 26 APDS2). Analysis of disease evolution in the first 68 patients pinpoints the early occurrence of recurrent respiratory infections followed by chronic lymphoproliferation, gastrointestinal manifestations, and cytopenias. Although most manifestations occur by age 15, adult-onset and asymptomatic courses were documented. Bronchiectasis was observed in 24/40 APDS1 patients who received a CT-scan compared with 4/15 APDS2 patients. By age 20, half of the patients had received at least one immunosuppressant, but 2–3 lines of immunosuppressive therapy were not unusual before age 10. Response to rapamycin was rated by physician visual analog scale as good in 10, moderate in 9, and poor in 7. Lymphoproliferation showed the best response (8 complete, 11 partial, 6 no remission), while bowel inflammation (3 complete, 3 partial, 9 no remission) and cytopenia (3 complete, 2 partial, 9 no remission) responded less well. Hence, non-lymphoproliferative manifestations should be a key target for novel therapies. This report from the ESID-APDS registry provides comprehensive baseline documentation for a growing cohort that will be followed prospectively to establish prognostic factors and identify patients for treatment studies

Experimentelle Untersuchungen zum Bubble Point an verschiedenen metallischen Sieben

Innerhalb dieser Arbeit wurden Untersuchungen zum Gasrückhaltevermögen von Metallgeweben hinsichtlich des Einflusses der Siebdehnung durchgeführt. Zunächst wurden Aufbau und Eigenschaften der verwendeten Siebe erläutert, um anschließend auf die physikalischen Grundlagen des Bubble Points einzugehen. Dazu zählte vor allem Oberflächenspannung, daraus resultierenden Kapillarkräfte und die Blasenbildung in den Siebporen. Weiterhin wurde eine eingehende Betrachtung vergangener Untersuchungen durchgeführt, um Einflussparameter auf das Gasrückhaltevermögen herauszustellen. Anschließend wurden nach Aufgabenstellung Messungen zum Bubble Point Druck hinsichtlich des Einflusses der Siebprobengröße durchgeführt. Dabei konnte der Probendurchmesser mit insgesamt fünf Durchmessern variiert werden. Es wurde zunächst ausführlich auf die Untersuchungsziele und deren Umfang eingegangen, um anschließend Versuchsaufbau, -vorbereitung und -durchführung zu erläutern. Im Anschluss wurden die systematischen und zufälligen Messfehler analysiert und berechnet. Die Resultate der Messungen wurden aufgeteilt in Ergebnisse der Druckmessung und Distanzmessung tabellarisch und grafisch vorgestellt, sowie miteinander in Beziehung gesetzt und diskutiert. Weiterhin wurden Beobachtungen zum Resealverhalten beschrieben und die Druckmessdaten anschließend in Bezug zu Literaturdaten eingeordnet. Schließlich wurde in zwei Ansätzen versucht Modelle zu finden, mit denen sich die Sieburchbiegung und dessen Einfluss auf den BP Druck beschreiben lässt

The regolith rocket—A hybrid rocket using lunar resources

The use of lunar hybrid rockets, that connect the Moon surface with a lunar gateway and provide it with resources, are evaluated. Therefore, the composition of lunar regolith and its use for specific rocket subsystems is assessed. In particular, this work evaluates the use of oxygen and aluminum from regolith as oxidant/fuel mixture as well as the use of alloys from regolith for the tanks and fairing of the considered rockets. It shows the advantages of in-situ resource utilization for the rocket development. Further, it depicts the current limitations that arise when developing such a technolog

Disease evolution and response to rapamycin in activated phosphoinositide 3-kinase δ syndrome : The European society for immunodeficiencies-activated phosphoinositide 3-kinase δ syndrome registry

Activated phosphoinositide 3-kinase (PI3K) δ Syndrome (APDS), caused by autosomal dominant mutations in PIK3CD (APDS1) or PIK3R1 (APDS2), is a heterogeneous primary immunodeficiency. While initial cohort-descriptions summarized the spectrum of clinical and immunological manifestations, questions about long-term disease evolution and response to therapy remain. The prospective European Society for Immunodeficiencies (ESID)-APDS registry aims to characterize the disease course, identify outcome predictors, and evaluate treatment responses. So far, 77 patients have been recruited (51 APDS1, 26 APDS2). Analysis of disease evolution in the first 68 patients pinpoints the early occurrence of recurrent respiratory infections followed by chronic lymphoproliferation, gastrointestinal manifestations, and cytopenias. Although most manifestations occur by age 15, adult-onset and asymptomatic courses were documented. Bronchiectasis was observed in 24/40 APDS1 patients who received a CT-scan compared with 4/15 APDS2 patients. By age 20, half of the patients had received at least one immunosuppressant, but 2-3 lines of immunosuppressive therapy were not unusual before age 10. Response to rapamycin was rated by physician visual analog scale as good in 10, moderate in 9, and poor in 7. Lymphoproliferation showed the best response (8 complete, 11 partial, 6 no remission), while bowel inflammation (3 complete, 3 partial, 9 no remission) and cytopenia (3 complete, 2 partial, 9 no remission) responded less well. Hence, non-lymphoproliferative manifestations should be a key target for novel therapies. This report from the ESID-APDS registry provides comprehensive baseline documentation for a growing cohort that will be followed prospectively to establish prognostic factors and identify patients for treatment studies

Analysis of Outcomes in Ischemic vs Nonischemic Cardiomyopathy in Patients With Atrial Fibrillation A Report From the GARFIELD-AF Registry

IMPORTANCE Congestive heart failure (CHF) is commonly associated with nonvalvular atrial fibrillation (AF), and their combination may affect treatment strategies and outcomes