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A Novel LQI Control Technique for Interleaved-Boost Converters.
No full textHybrid electric vehicles (HEVs) and fuel cell electric vehicles (FCEVs) utilize boost converters to gain a higher voltage than the battery. Interleaved boost converters are suitable for low input voltage, large input current, miniaturization, and high-efficiency applications. This paper proposes a novel linear quadratic integral (LQI) control for the interleaved boost converters. First, the small-signal model of the interleaved-boost converter is derived. In the proposed method, an output voltage and a current signal error between two-phase input currents are selected to control not only the output voltage but also a balance between two-phase input currents. Furthermore, steady-state characteristics in terms of the output voltage and the input current are demonstrated by experiments and simulations using an experimental apparatus with a rated power of 700 W. The validity of the proposed method’s tracking performance and load response is demonstrated by comparing it with that of the conventional PI control. The tracking performance of the LQI control for the 40 V step response has a ten times faster response than that of the PI control. Also, the experimental results demonstrate that the proposed method maintains a constant output voltage for a 300 W load step while the PI control varies by 10 V during 70 ms. Additionally, the proposed method has an excellent disturbance rejection
Be prepared for the unexpected: Mind-stretching in ST-elevation myocardial infarction with situs inversus totalis.
No full textSitus inversus totalis is a rare diagnosis, but the likelihood of experiencing myocardial infarction is presumed to be comparable to the general population average. In individuals exhibiting situs inversus with suspected myocardial infarction, ECG recording, including right precordial leads, is crucial for diagnostic assessment. Coronary angiography and intervention should be performed with standard equipment using inverted maneuvers and radiographic projections
Myeloid cannabinoid CB1 receptor deletion confers atheroprotection in male mice by reducing macrophage proliferation in a sex-dependent manner.
No full textAIMS: Although the cannabinoid CB1 receptor has been implicated in atherosclerosis, its cell-specific effects in this disease are not well understood. To address this, we generated a transgenic mouse model to study the role of myeloid CB1 signalling in atherosclerosis.
METHODS AND RESULTS: Here, we report that male mice with myeloid-specific Cnr1 deficiency on atherogenic background developed smaller lesions and necrotic cores than controls, while only minor genotype differences were observed in females. Male Cnr1-deficient mice showed reduced arterial monocyte recruitment and macrophage proliferation with less inflammatory phenotype. The sex-specific differences in proliferation were dependent on oestrogen receptor (ER)α-oestradiol signalling. Kinase activity profiling identified a CB1-dependent regulation of p53 and cyclin-dependent kinases. Transcriptomic profiling further revealed chromatin modifications, mRNA processing, and mitochondrial respiration among the key processes affected by CB1 signalling, which was supported by metabolic flux assays. Chronic administration of the peripherally restricted CB1 antagonist JD5037 inhibited plaque progression and macrophage proliferation, but only in male mice. Finally, CNR1 expression was detectable in human carotid endarterectomy plaques and inversely correlated with proliferation, oxidative metabolism, and inflammatory markers, suggesting a possible implication of CB1-dependent regulation in human pathophysiology.
CONCLUSION: Impaired macrophage CB1 signalling is atheroprotective by limiting their arterial recruitment, proliferation, and inflammatory reprogramming in male mice. The importance of macrophage CB1 signalling appears to be sex-dependent
Resolving spatial response heterogeneity in glioblastoma.
No full textPURPOSE: Spatial intratumoral heterogeneity poses a significant challenge for accurate response assessment in glioblastoma. Multimodal imaging coupled with advanced image analysis has the potential to unravel this response heterogeneity.
METHODS: Based on automated tumor segmentation and longitudinal registration with follow-up imaging, we categorized contrast-enhancing voxels of 61 patients with suspected recurrence of glioblastoma into either true tumor progression (TP) or pseudoprogression (PsP). To allow the unbiased analysis of semantically related image regions, adjacent voxels with similar values of cerebral blood volume (CBV), FET-PET, and contrast-enhanced T1w were automatically grouped into supervoxels. We then extracted first-order statistics as well as texture features from each supervoxel. With these features, a Random Forest classifier was trained and validated employing a 10-fold cross-validation scheme. For model evaluation, the area under the receiver operating curve, as well as classification performance metrics were calculated.
RESULTS: Our image analysis pipeline enabled reliable spatial assessment of tumor response. The predictive model reached an accuracy of 80.0% and a macro-weighted AUC of 0.875, which takes class imbalance into account, in the hold-out samples from cross-validation on supervoxel level. Analysis of feature importances confirmed the significant role of FET-PET-derived features. Accordingly, TP- and PsP-labeled supervoxels differed significantly in their 10th and 90th percentile, as well as the median of tumor-to-background normalized FET-PET. However, CBV- and T1c-related features also relevantly contributed to the model's performance.
CONCLUSION: Disentangling the intratumoral heterogeneity in glioblastoma holds immense promise for advancing precise local response evaluation and thereby also informing more personalized and localized treatment strategies in the future
Pig models for translational Duchenne muscular dystrophy research.
No full textDuchenne muscular dystrophy (DMD) is caused by mutations in the X-linked DMD gene, resulting in the absence of dystrophin, progressive muscle degeneration, and heart failure. Genetically tailored pig models resembling human DMD mutations recapitulate the biochemical, clinical, and pathological hallmarks of DMD with an accelerated disease progression compared to human patients. DMD pigs have been used to evaluate therapeutic concepts such as gene editing to reframe a disrupted DMD reading frame or the delivery of artificial chromosome vectors carrying the complete DMD gene. Moreover, DMD pigs have been instrumental in validating new diagnostic modalities such as multispectral optoacoustic tomography (MSOT) for non-invasive monitoring of disease progression. DMD pigs may thus help to bridge the gap between proof-of-concept studies in cellular or rodent models and clinical studies in patients
Cytokine profile in peripheral blood mononuclear cells differs between embryo donor and potential recipient sows.
No full textINTRODUCTION: Pregnancy success relies on the establishment of a delicate immune balance that requires the early activation of a series of local and systemic immune mechanisms. The changes in the immunological profile that are normally occurring in the pregnant uterus does not take place in cyclic (non-pregnant) uterus, a fact that has been widely explored in pigs at the tissue local level. Such differences would be especially important in the context of embryo transfer (ET), where a growing body of literature indicates that immunological differences at the uterine level between donors and recipients may significantly impact embryonic mortality. However, whether components of peripheral immunity also play a role in this context remains unknown. Accordingly, our hypothesis is that the immune status of donor sows differs from potential recipients, not only at the tissue local level but also at the systemic level. These differences could contribute to the high embryonic mortality rates occurring in ET programs.
METHODS: In this study differences in systemic immunity, based on cytokine gene expression profile in peripheral blood mononuclear cells (PBMCs), between embryo-bearing donor (DO group; N = 10) and potential recipient sows (RE group; N = 10) at Day 6 after the onset of the estrus were explored. Gene expression analysis was conducted for 6 proinflammatory (IL-1α, IL-1β, IL-2, GM-CSF, IFN-γ, and TNF-α) and 6 anti-inflammatory (IL-4, IL-6, IL-10, IL-13, TGF-β1, and LIF) cytokines.
RESULTS AND DISCUSSION: All cytokines were overexpressed in the DO group except for IL-4, suggesting that stimuli derived from the insemination and/or the resultant embryos modify the systemic immune profile in DO sows compared to RE (lacking these stimuli). Our results also suggest that certain cytokines (e.g., IL-1α and IL-1β) might have a predictive value for the pregnancy status
Comparing the quality of care in physician networks to usual care for elderly patients in three German regions: a quasi-experimental cohort study
No full textResilience in Platoons of Cooperative Heterogeneous Vehicles: Self-Organization Strategies and Provably-Correct Design
No full textinsites 2019 - 2024. Landschaftsarchitektur und Transformation
No full text„insites 2019-2024“ ist der vierte Band in einer Reihe, die seit 2007 produziert wird. „insites 2002-2007“ bot einen Einblick in die Arbeit am Lehrstuhl für Landschaftsarchitektur und Entwerfen der Gottfried Wilhelm Leibniz Universität Hannover, wohin Udo Weilacher im Oktober 2002 berufen wurde. „insites 2009 – 2014“ porträtierte die fünfjährige Startphase seines Lehrstuhls an der TUM, an der Udo Weilacher im April 2009 die Nachfolge von Peter Latz antrat. Danach erschien „insites 2014 -2019“ und nun also: „insites 2019-2024“.
Die hier skizzierten fünf Jahre Forschung und Lehre waren nicht nur gekennzeichnet von der Umbenennung des Lehrstuhles und einer Strukturreform an der TUM. Starken Einfluss hatte zudem eine Krise, die im Frühjahr 2020 begann und im April 2023 vom Bundesminister für Gesundheit der Bundesrepublik Deutschland für beendet erklärt wurde: die COVID-19-Pandemie. Wissbegierige Studierende sowie Projektpartner aus aller Welt haben dafür gesorgt, dass in dieser Publikation viele ausgezeichneten Projekte präsentiert werden können.
Besonders bereichernd waren drei große Kooperationsprojekte, die in den vergangenen fünf Jahren erfolgreich abgeschlossen und publiziert wurden. Das Buch „Crossing Borders – Activating Spaces“ erschien 2021 und dokumentiert die Ergebnisse des dritten Zyklus‘ des Internationalen Doktorandenkollegs „Forschungslabor-Raum“ (2017 – 2020) unter dem Leitthema „Grenzen überschreiten – Räume aktivieren“. Das gemeinsam von der TUM, der ETH Zürich, dem KIT Karlsruhe sowie den TU‘s in Berlin, Wien und Dortmund getragene Graduiertenkolleg bot mehr als 20 Doktorierenden die Chance, sich einem interdisziplinären akademischen Feld zu präsentieren und ihre Promotionen erfolgreich abzuschließen. Ebenfalls 2021 erschien die Dokumentation zum dreijährigen Forschungsprojekt „Alpine Industrial Landscapes Transformation – trAILs“ , an dem unter der Regie des Lehrstuhls LAT zehn Partnerinstitutionen aus fünf Europäischen Alpenländern beteiligt waren, gefördert vom Europäischen Interreg Alpine Space Programm. Last not least gelang es seit 2021 in Zusammenarbeit mit der ägyptischen Gastwissenschaftlerin Dr. Sara Fouad, Stipendiatin der Alexander von Humboldt Stiftung, und dem NASA-Wissenschaftler Dr. Essam Heggy von der Viterbi School of Engineering an der University of Southern California eine Reihe international vielzitierter Fachartikel zu veröffentlichen, die sich mit den gravierenden Folgen des Klimawandels in mediterranen Küstenregionen befassen