Technische Universität Dresden: Qucosa
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Migraine with aura: less control over pain and fragrances?
No full textBackground:
Accumulating data emphasizes the importance of olfaction in migraine pathophysiology. However, there are only a few studies evaluating how the migraine brain processes olfactory stimulation, and virtually no studies comparing patients with and without aura in this context.
Methods:
This cross-sectional study recorded event-related potentials from 64 electrodes during a pure olfactory or pure trigeminal stimulus in females with episodic migraine with aura (n = 13) and without aura (n = 15), to characterize the central nervous processing of these intranasal stimuli. Patients were tested in interictal state only. Data were analyzed in the time domain and in the time–frequency domain. Source reconstruction analysis was also performed.
Results:
Patients with aura had higher event-related potentials amplitudes for left-sided trigeminal and left-sided olfactory stimulations, and higher neural activity for right-sided trigeminal stimulation in brain areas related to trigeminal and visual processing. Following olfactory stimulations patients with aura displayed decreased neural activity in secondary olfactory structures compared to patients without aura. Oscillations in the low frequency bands (< 8 Hz) differed between patient groups.
Conclusions:
Altogether this may reflect hypersensitivity to nociceptive stimuli in patients with aura relative to patients without aura. Patients with aura have a bigger deficit in engaging secondary olfactory-related structures, possibly leading to distorted attention and judgements towards odors. The cerebral overlap between trigeminal nociception and olfaction might explain these deficits
Nanographene-Based Heterojunctions for High-Performance Organic Phototransistor Memory Devices
No full textOrganic phototransistors can enable many important applications such as nonvolatile memory, artificial synapses, and photodetectors in next-generation optical communication and wearable electronics. However, it is still a challenge to achieve a big memory window (threshold voltage response ∆Vₜₕ) for phototransistors. Here, a nanographene-based heterojunction phototransistor memory with large ∆Vₜₕ responses is reported. Exposure to low intensity light (25.7 µW cm⁻²) for 1 s yields a memory window of 35 V, and the threshold voltage shift is found to be larger than 140 V under continuous light illumination. The device exhibits both good photosensitivity (3.6 × 10⁵) and memory properties including long retention time (>1.5 × 10⁵ s), large hysteresis (45.35 V), and high endurance for voltage-erasing and light-programming. These findings demonstrate the high application potential of nanographenes in the field of optoelectronics. In addition, the working principle of these hybrid nanographene-organic structured heterojunction phototransistor memory devices is described which provides new insight into the design of high-performance organic phototransistor devices
Understanding MOF Flexibility: an Analysis Focused on Pillared Layer MOFs as a Model System
No full textFlexible porous frameworks are at the forefront of materials research. A unique feature is their ability to open and close their pores in an adaptive manner induced by chemical and physical stimuli. Such enzyme-like selective recognition offers a wide range of functions ranging from gas storage and separation to sensing, actuation, mechanical energy storage and catalysis. However, the factors affecting switchability are poorly understood. In particular, the role of building blocks, as well as secondary factors (crystal size, defects, cooperativity) and the role of host–guest interactions, profit from systematic investigations of an idealized model by advanced analytical techniques and simulations. The review describes an integrated approach targeting the deliberate design of pillared layer metal–organic frameworks as idealized model materials for the analysis of critical factors affecting framework dynamics and summarizes the resulting progress in their understanding and application
VARC‑3 defined outcome of valve‑in‑valve transcatheter aortic valve implantation in stentless compared with stented aortic bioprostheses
No full textBackground:
Valve-in-valve (ViV) transcatheter aortic valve implantation (TAVI) is a viable alternative to redo surgery in selected patients with bioprosthetic valve dysfunction. Most ViV-TAVI procedures have been performed in stented bioprosthetic valves (ST); stentless bioprostheses (SL) lack fluoroscopic markers and could be more challenging for ViV-TAVI. Data on more recent patients applying Valve Academic Research Consortium (VARC)-3 defined outcomes are scarce. We compared patient characteristics, procedural outcomes, and 5-year mortality of patients with SL versus ST aortic bioprosthetic valve failure undergoing ViV-TAVI.
Methods:
Patients undergoing ViV-TAVI between 2007 and 2022 (52.5% of cases after 2015) at 3 German centers were included in this analysis. The co-primary outcome measures were technical success, device success, and early safety defined by VARC-3. Mortality was assessed up to 5 years.
Results:
Overall, 43 (11.8%) SL and 313 (88.2%) ST ViV-TAVI were included. Patients were comparable with regard to age, sex, clinically relevant baseline comorbidities, and surgical risk. - Technical success (SL: 83.7% versus ST: 79.9%, p = 0.552), device success (SL: 67.4% versus ST: 54.3%, p = 0.105), and early safety (SL: 74.4% versus ST: 66.5%, p = 0.296) were comparable between groups. The 30-day mortality (SL: 7.0% versus ST: 2.6%, p = 0.136) and 5-year mortality rates (SL: 23.3% versus ST: 24.6%, p = 0.874) were not significantly different between groups.
Conclusion:
SL and ST ViV-TAVI led to comparable short-term outcomes according to VARC-3- defined endpoints and similar mortality rates up to 5 years of follow-up
Quantum scale invariance in gauge theories and applications to muon production
No full textWe discuss quantum scale invariance in (scale invariant) gauge theories with both ultraviolet (UV) and infrared (IR) divergences. First, their Becchi-Rouet-Stora-Tyutin invariance is checked in two apparently unrelated approaches using a scale invariant regularization (SIR). These approaches are then shown to be equivalent. Second, for the Abelian case we discuss both UV and IR quantum corrections present in such theories. We present the Feynman rules in a form suitable for off-shell Green’s function calculations, together with their one-loop renormalization. This information is then used for the muon production cross section at one-loop in a quantum scale invariant theory. Such a theory contains not only new UV poles but also IR poles. While the UV poles bring new quantum corrections (in the form of counterterms), finite or divergent, that we compute, it is shown that the IR poles do not bring new physics. The IR quantum corrections, both finite and divergent, cancel out similarly to the way the IR poles themselves cancel in the traditional approach to IR divergences (in the cross section, after summing over virtual and real corrections). Hence, the evanescent interactions induced by the scale-invariant analytical continuation of the SIR scheme do not affect IR physics, as illustrated at one-loop for the muon production (+− →+−) cross section
Priapism at Diagnosis of Pediatric Chronic Myeloid Leukemia: Data Derived from a Large Cohort of Children and Teenagers and a Narrative Review on Priapism Management
No full textPediatric chronic myeloid leukemia (CML) is a very rare malignancy (age-related incidence 0.1/100,000) typically presenting with leucocyte counts >100,000/µL. However, clinical signs of leukostasis are observed at diagnosis in only approximately 10% of all cases and among these, priapism is infrequent. Here, we analyze data from pediatric CML registries on the occurrence of priapism heralding diagnosis of CML in 16/491 (3.2%) boys (median age 13.5 years, range 4–18) with pediatric CML. In the cohort investigated, duration of priapism resulting in a diagnosis of CML was not reported in 5 patients, and in the remaining 11 patients, occurred as stuttering priapism over 3 months (n = 1), over 6 weeks (n = 1), over 1–2 weeks (n = 2), over several days (n = 2), or 24 h (n = 1), while the remaining 4 boys reported continuous erection lasting over 11–12 h. All patients exhibited splenomegaly and massive leukocytosis (median WBC 470,000/µL, range 236,700–899,000). Interventions to treat priapism were unknown in 5 patients, and in the remaining cohort, comprised intravenous fluids ± heparin (n = 2), penile puncture (n = 5) ± injection of sympathomimetics (n = 4) ± intracavernous shunt operation (n = 1) paralleled by leukocyte-reductive measures. Management without penile puncture by leukapheresis or exchange transfusion was performed in 3 boys. In total, 7 out 15 (47%) long-term survivors (median age 20 years, range 19–25) responded to a questionnaire. All had maintained full erectile function; however, 5/7 had presented with stuttering priapism while in the remaining 2 patients priapism had lasted <12 h until intervention. At its extreme, low-flow priapism lasting for longer than 24 h may result in partial or total impotence by erectile dysfunction. This physical disability can exert a large psychological impact on patients’ lives. In a narrative review fashion, we analyzed the literature on priapism in boys with CML which is by categorization stuttering or persisting as mostly painful, ischemic (low-flow) priapism. Details on the pathophysiology are discussed on the background of the different blood rheology of hyperleukocytosis in acute and chronic leukemias. In addition to the data collected, instructive case vignettes demonstrate the diagnostic and treatment approaches and the outcome of boys presenting with priapism. An algorithm for management of priapism in a stepwise fashion is presented. All approaches must be performed in parallel with cytoreductive treatment of leukostasis in CML which comprises leukapheresis and exchange transfusions ± cytotoxic chemotherapy
Quantum Dots Facilitate 3D Two-Photon Laser Lithography
No full textIn the past two decades, direct laser writing (DLW) technologies have seen tremendous growth. However, strategies that enhance the printing resolution and the development of printing material with assorted functionalities are still sparser than expected. Herein, a cost-effective method to tackle this bottleneck is presented. Semiconductor quantum dots (QDs) are selected to carry out this task, most importantly via surface chemistry modification to enable their copolymerization with themonomers, resulting in transparent composites. The evaluations indicate that the QDs show great colloidal stability and their photoluminescent properties are well-preserved. This allows further exploration of the printing characteristics of such composite material. It is shown that in the presence of the QDs, the material provides a much lower polymerization threshold with faster linewidth growth, indicating that the QDs form a synergetic relationship with the monomer and the photoinitiator, widening the dynamic range of the material and thus increasing the writing efficiency for broader fields of applications. Lowering the polymerization threshold reduces the minimum achievable feature size by ≈32%, which is well-matched with STED-based (i.e., stimulated-emission depletion microscopy) methods in writing 3D structures. The study further elucidates the mechanism of the synergetic behavior, further guiding the future development of functional materials for DLW-related printing technologies
Prozess
No full text:Aufarbeitung des Prozesses / Edition der Akten
Vorgeschichte
Erste Verfahren in Frankreich
Erstes Verfahren
Zweites Verfahren
Drittes Verfahren
Diözesankommissionen in Frankreich
Kommission gegen den Orden als Institution in Paris
Die Verfahren außerhalb Frankreichs
Flandern
Patrimonium Petri, Abruzzen, Spoleto
Lombardei, Toskana, Romagna
Königreich Neapel, Sizilien
Aragon, Katalonien, Leon, Kastilien, Navarra und Portugal
England, Schottland und Irland
Deutschland (inklusive der damaligen Ostgebiete)
Zypern
Ende des Prozesses
Lage im Templerorden
Amtsmissbrauchs- und Häresievorwürfe gegen andere Orden
Der Streit mit Papst Bonifatius VIII.
Nachleben des Prozesses
Quellen
Arrestationsbefehl und Briefe der Inquisition
Publizistik
Verhörprotokolle im Original
Editionen/Übersetzungen der Protokolle und weiterer Schriftstück
Investigations on the bond behaviour of a hybrid lap-spliced connection of GFRP and stainless steel bars
No full textAs the global population continues to grow, the demand for energy also increases, leading to a significant rise in the resource consumption, notably the electricity and fuel oil. Consequently, enhancing energy efficiency has become an urgent necessity, not only to protect the environment but also to mitigate financial burdens. In the insulation joint of a traditional balcony structure, normal steel bars with high thermal conductivity are used as tension bars to connect the interior and exterior structures. This has caused significant energy losses due to the formation of serious thermal bridges. In comparison, the thermal conductivity of glass fiber reinforced polymer (GFRP) material is significantly lower, at only 1% of that of steel. It can be an ideal substitution for the tension steel bars in the joints. Thus, this introduces a novel hybrid lap-spliced connection between GFRP bars and steel bars in the adjacent structures, which has rarely been investigated.
In the first publication of this cumulative dissertation, comprehensive knowledge regarding the tensile lap-spliced steel and FRP bars in flexural concrete specimens is collected and systematically analyzed. Building on the results, a three-level based investigation method is outlined to study the mechanical behavior of the hybrid lap-spliced connection between GFRP bars and steel bars. In the second publication, the first two levels are presented. First, the tension tests on two types of GFRP bars and one type of stainless steel bar are conducted to obtain their mechanical properties, respectively. In the subsequent bond tests, the bond performance between concrete and one single bar is investigated using distributed fiber optical sensors (DFOSs). Four combinations of DFOSs and adhesives are applied in the grooves of one type of GFRP bars to investigate their influence on the measured bar strains. Next, the determined best variant is further implemented in other two types of bars to study their different bond behaviors in concrete. The third publication primarily focuses on investigating the third level, specifically the actual lap-spliced connections. In the first step, the microstructural characterization of GFRP bars is analyzed to comprehend their specific material properties. In the second step, the optimal direction of grooves for placing DFOSs in the bars is determined through cantilever tests. In the third step, the influence of lap-spliced length and lap-spliced type on the bond performances of hybrid lap-spliced bars is investigated with four-point flexural tests. The strain distributions of lap-spliced bars, in particular in the lap-spliced area are investigated in-depth. Besides, the strains and stresses at the lap-spliced ends at different loads are analyzed. Furthermore, the maximum experimental loads are compared with calculated results of the ultimate strength method.
At the end of this work, several further studies are carried out. Firstly, the bar strain distributions in bond tests and four-point flexural tests are compared. Besides, the cracks focusing on the lap-spliced area in the four-point flexural tests are analyzed. Moreover, numerical simulations are conducted to validate the experimental results of the bond tests and the four-point flexural tests. Subsequently, parameter studies are carried out based on the validated models to determine the critical development length of the GFRP bars in bond test as well as the optimal lap-spliced length between GFRP bars and stainless steel bars in four-point flexural test. The results are then compared with the results calculated with different national and international standards.
Based on the abovementioned investigations, it can be concluded that the substitution of steel bars with GFRP bars not only enhances the thermal behavior of the lap-spliced connection, but also increases the mechanical performance such as load capacity of the reinforced concrete structures. In addition, the provisions in current standards to calculate the development and lap-spliced lengths require further improvements, including experimental investigations and numerical validations, to achieve more accurate results.:Contents i
1 Introduction 1
1.1 Research background and motivation 1
1.2 Research objective and scope 1
1.3 Thesis outline 2
2 Publications 5
2.1 Lap-spliced connections of steel and FRP bars in reinforced flexure concrete structures 7
2.2 Investigations on bond performances of GFRP/stainless steel reinforcements using distributed fiber optical sensors (DFOSs) 25
2.3 Experimental investigation on the bond performance of a hybrid lap-spliced connection of GFRP and stainless steel bars in concrete 49
3 Further investigations 69
3.1 The comparison of strain distributions in bond and four-point flexural tests 69
3.2 Concrete cracks in four-point flexural test 70
3.2.1 Crack detection with DFOS 70
3.2.2 Crack width 72
3.2.3 Crack spacing 74
3.3 Critical development length 76
3.3.1 Specification in standards 76
3.3.2 Numerical modeling 77
3.3.3 Comparison between calculated and simulated results 81
3.4 Optimal lap-spliced length 81
3.4.1 Numerical modeling 81
3.4.2 Specification in standards 85
3.4.3 Comparison between calculated and simulated results 86
4 Conclusion and outlook 87
References 89Mit dem anhaltenden weltweiten Bevölkerungswachstum steigt auch der Energiebedarf, was zu einem erheblichen Anstieg des Ressourcenverbrauchs führt – insbesondere im Bereich Strom und Heizöl. Infolgedessen ist eine Steigerung der Energieeffizienz zu einer dringenden Notwendigkeit geworden, nicht nur zum Schutz der Umwelt, sondern auch zur Reduzierung finanzieller Belastungen. Bei traditionellen Balkonanschlüssen werden in den Isolationsfugen gewöhnliche Stahlbewehrungen mit hoher Wärmeleitfähigkeit als Zugstäbe eingesetzt, um Innen- und Außenbereiche miteinander zu verbinden. Dies führt zu erheblichen Energieverlusten aufgrund ausgeprägter Wärmebrücken. Im Vergleich dazu weist das Material glasfaserverstärkter Kunststoff (GFRP) eine deutlich geringere Wärmeleitfähigkeit auf – nur etwa 1 % derjenigen von Stahl. Daher ist GFRP ein idealer Ersatz für Stahlstäbe in solchen Anschlussbereichen. In dieser Dissertation wird daher eine neuartige hybride Übergreifungs-Verbindung (Lap-Splice) zwischen GFRP-Stäben und Stahlstäben in benachbarten Bauteilen vorgestellt, die bisher kaum erforscht ist.
In der ersten Publikation dieser kumulativen Dissertation wird umfassendes Wissen über die Übergreifung von GFRP- und Stahlstäben in biegebeanspruchten Betonbauteilen zusammengetragen und systematisch ausgewertet. Aufbauend auf diesen Ergebnissen wird eine Untersuchungsmethodik in drei Stufen entwickelt, um das mechanische Verhalten der hybriden Übergreifungsverbindung zwischen GFRP- und Stahlstäben zu analysieren. In der zweiten Publikation werden die ersten beiden Stufen dieser Methodik vorgestellt. Zunächst werden Zugversuche mit zwei Typen von GFRP-Stäben und einem Typ Edelstahlstab durchgeführt, um deren mechanische Eigenschaften zu ermitteln. In nachfolgenden Verbundversuchen wird das Verbundverhalten zwischen Beton und jeweils einem Einzelstab untersucht. Dabei kommen vier Kombinationen aus verteilten faseroptischen Sensoren (DFOS) und Klebstoffen in den Längsnuten eines GFRP-Stabtyps zum Einsatz, um deren Einfluss auf die gemessenen Stabdehnungen zu analysieren. Die ermittelte optimale Kombination wird anschließend auch bei den anderen zwei Stabtypen eingesetzt, um deren unterschiedliches Verbundverhalten im Beton zu untersuchen.
Die dritte Publikation konzentriert sich hauptsächlich auf die dritte Stufe, nämlich auf tatsächliche Übergreifungsverbindungen. Im ersten Schritt wird die Mikrostruktur der GFRP-Stäbe analysiert, um deren spezifische Materialeigenschaften zu verstehen. Im zweiten Schritt wird durch Kragarmversuche die optimale Ausrichtung der DFOS-Nuten bestimmt. Im dritten Schritt werden der Einfluss der Übergreifungslänge sowie des Übergreifungstyps auf das Verbundverhalten in hybriden Übergreifungsverbindungen mittels Vier-Punkt-Biegeversuchen untersucht. Besonders die Dehnungsverteilungen im Bereich der Übergreifung werden detailliert analysiert. Darüber hinaus werden die Dehnungen und Spannungen an den Übergreifungsenden bei unterschiedlichen Belastungen erfasst. Abschließend werden die maximalen experimentellen Lasten mit den Ergebnissen der Berechnung nach dem Grenzzustandsverfahren verglichen.
Am Ende der Dissertation werden mehrere weiterführende Untersuchungen durchgeführt. Zunächst erfolgt ein Vergleich der Stabdehnungsverteilungen zwischen den Verbundversuchen und den Vier-Punkt-Biegeversuchen. Zusätzlich werden die Rissbilder im Übergreifungsbereich der Biegeversuche analysiert. Anschließend werden numerische Simulationen durchgeführt, um die experimentellen Ergebnisse aus den Verbund- und Biegeversuchen zu validieren. Darauf aufbauend werden Parameterstudien mit den validierten Finite-Elemente-Modellen (FEM) durchgeführt, um die kritische Verankerungslänge der GFRP-Stäbe sowie die optimale Übergreifungslänge zwischen GFRP- und Edelstahlstäben zu bestimmen. Die Ergebnisse werden abschließend mit Berechnungen nach verschiedenen nationalen und internationalen Normen verglichen.
Auf Grundlage der oben genannten Untersuchungen kann geschlossen werden, dass der Ersatz von Stahlstäben durch GFRP-Stäbe nicht nur das thermische Verhalten der Übergreifungsverbindung verbessert, sondern auch die mechanische Leistungsfähigkeit, wie beispielsweise die Tragfähigkeit von Stahlbetonbauteilen, steigert. Darüber hinaus zeigt sich, dass die in den aktuellen Normen enthaltenen Regelwerke zur Bestimmung von Verankerungs- und Übergreifungslängen weiterer Überarbeitung bedürfen. Hierzu sind zusätzliche experimentelle und numerische Untersuchungen erforderlich, um genauere und verlässlichere Ergebnisse zu erzielen.:Contents i
1 Introduction 1
1.1 Research background and motivation 1
1.2 Research objective and scope 1
1.3 Thesis outline 2
2 Publications 5
2.1 Lap-spliced connections of steel and FRP bars in reinforced flexure concrete structures 7
2.2 Investigations on bond performances of GFRP/stainless steel reinforcements using distributed fiber optical sensors (DFOSs) 25
2.3 Experimental investigation on the bond performance of a hybrid lap-spliced connection of GFRP and stainless steel bars in concrete 49
3 Further investigations 69
3.1 The comparison of strain distributions in bond and four-point flexural tests 69
3.2 Concrete cracks in four-point flexural test 70
3.2.1 Crack detection with DFOS 70
3.2.2 Crack width 72
3.2.3 Crack spacing 74
3.3 Critical development length 76
3.3.1 Specification in standards 76
3.3.2 Numerical modeling 77
3.3.3 Comparison between calculated and simulated results 81
3.4 Optimal lap-spliced length 81
3.4.1 Numerical modeling 81
3.4.2 Specification in standards 85
3.4.3 Comparison between calculated and simulated results 86
4 Conclusion and outlook 87
References 8