Ertüchtigung der Flachschleifmaschine ELB SF 30

Aufbauend auf dem Praktikumsbericht wird in der vorliegenden Bachelorarbeit, das Thema „Ertüchtigung der Flachschleifmaschine ELB“ weiter behandelt. Es wird dabei speziell die Einführung eines neuen Bedienpanels an der Maschine konkretisiert. Zu Beginn erfolgt die Auswahl eines geeigneten Panels, welches zu der vorhandenen Steuerung kompatibel ist. Daraufhin folgt die Vorstellung der Visualisierungssoftware, sowie der Software zum Testen der projektierten Oberfläche des Bediengerätes. Im weiteren Verlauf finden sich Erläuterungen zur Programmierung des Panels, bezogen auf das ELB-Projekt wieder. Das letzte Kapitel bezieht sich auf die konkrete SPS-Lösung zwei ausgewählter Steuerungsfunktionen, zum einen die Magnetsteuerung und zum anderen die Querantriebsteuerung

Seismic capacity and multi-mechanism analysis for dry-stack masonry arches subjected to hinge control

Masonry arches are vulnerable to seismic actions. Over the last few years, extensive research has been carried out to develop strategies and methods for their seismic assessment and strengthening. The application of constant horizontal accelerations to masonry arches is a well-known quasi-static method, which approximates dynamic loading effects and quantifies their stability, while tilting plane testing is a cheap and effective strategy for experimentation of arches made of dry-stack masonry. Also, the common strengthening techniques for masonry arches are mainly focusing on achieving full strength of the system rather than stability. Through experimentation of a dry-stack masonry arch it has been shown that the capacity of an arch can be increased, and the failure controlled by defining hinge positions through reinforcement. This paper utilizes experimentally obtained results to introduce: (1) static friction and resulting mechanisms; and (2) the post-minimum mechanism reinforcement requirements into the two-dimensional limit analysis-based kinematic collapse load calculator (KCLC) software designed for the static seismic analysis of dry-stack masonry arches. Computational results are validated against a series of experimental observations based on tilt plane tests and good agreement is obtained. Discrete element models to represent the masonry arch with different hinge configurations are also developed to establish a validation trifecta. The limiting mechanism to activate collapse of arches subjected to hinge control is investigated and insights into the optimal reinforcement to be installed in the arch are derived. It is envisaged that the current modelling approach can be used by engineers to understand stability under horizontal loads and develop strengthening criteria for masonry arches of their care

Independent Activation of Hepatitis B Virus Biosynthesis by Retinoids, Peroxisome Proliferators, and Bile Acids

In the human hepatoma cell line HepG2, retinoic acid, clofibric acid, and bile acid treatment can only modestly increase hepatitis B virus (HBV) biosynthesis. Utilizing the human embryonic kidney cell line 293T, it was possible to demonstrate that the retinoid X receptor α (RXRα) plus its ligand can support viral biosynthesis independently of additional nuclear receptors. In addition, RXRα/peroxisome proliferator-activated receptor α (PPARα) and RXRα/farnesoid X receptor α (FXRα) heterodimeric nuclear receptors can also mediate ligand-dependent HBV transcription and replication when activated by clofibric acid and bile acid, respectively, independently of a requirement for the ligand-dependent activation of RXRα. These observations indicate that there are at least three possible modes of ligand-mediated activation of HBV transcription and replication existing within hepatocytes, suggesting that multiple independent mechanisms control viral production in the livers of infected individuals

The efficacy of amino acid-based formulas in relieving the symptoms of cow's milk allergy: a systematic review

The aim of this systematic review was to evaluate the efficacy of amino acid-based formulas (AAF) in patients with cow's milk allergy (CMA). Studies were identified using electronic databases and bibliography searches. Subjects eligible for inclusion were patients of any age with CMA or symptoms suggestive of it. Comparisons of interest were AAF vs. extensively hydrolysed formula (eHF), AAF vs. soy-based formula (SF) and AAF vs. cow's milk or cow's milk-based formula. Outcomes of interest were gastrointestinal (GI), dermatological, respiratory and behavioural symptoms as well as growth. A total of 20 studies [three head-to-head randomized controlled trials (RCTs), three cross-over challenge RCTs, seven clinical trials (CTs) and seven case reports (CRs)] were included in the review. In infants with confirmed or suspected CMA, the use of an AAF was shown to be safe and efficacious. Findings from RCT comparisons of AAF with eHF showed that both formulas are equally efficacious at relieving the symptoms of CMA in confirmed or suspected cases. However, infants in specific subgroups (e.g. non-IgE mediated food-induced gastro-enterocolitisproctitis syndromes with failure to thrive, severe atopic eczema, or with symptoms during exclusive breastfeeding) were more likely overall to benefit from AAF, as intolerance to eHF may occur. In such cases, symptoms persisting despite eHF feeding usually remit on AAF, and catch-up growth may be seen. Meta-analysis of the findings was not possible due to lack of homogenous reporting of outcomes in the original trials. This systematic review shows clinical benefit from use of AAF in both symptoms and growth in infants and children with CMA who fail to tolerate eHF. Further studies are required to determine the relative medical or economic value of initial treatment with AAF in infants at high risk of eHF intolerance