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Digital skull anatomy of the Oligocene North American tortoise Stylemys nebrascensis with taxonomic comments on the species and comparisons with extant testudinids of the Gopherus–Manouria clade
Full text linkThe anatomy of North American tortoises is poorly understood, despite a rich fossil record from the Eocene and younger strata. Stylemys nebrascensis is a particularly noteworthy turtle in this regard, as hundreds of specimens are known from Oligocene deposits, and as this species is one of the earliest fossil turtles to have been described in the scientific literature. Since its initial description based on a shell, many specimens with more complete material have been referred to Stylemys nebrascensis . Here, we review and confirm the referral of an important historic specimen to Stylemys nebrascensis , which includes shell, non-shell postcranial, and skull material. This allows us to document unique skull features of Stylemys nebrascensis (e.g., an unusual ‘poststapedial canal’ that connects the posterior skull surface with the cavum acustico-jugulare) and to refer another well-preserved skull to the species. Based on computed-tomography scanning of these two skulls, we provide a detailed description of the cranial and mandibular osteology of Stylemys nebrascensis . Stylemys nebrascensis has a combination of plesiomorphic skull characteristics (e.g., retention of a medial jugal process) and derived traits shared with extant gopher tortoises (e.g., median premaxillary ridge) that suggest it may be a stem-representative of the gopher tortoise lineage. This supports the hypothesis that extant and fossil tortoises from North America form a geographically restricted clade that split from Asian relatives during the Paleogene.Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschunghttp://dx.doi.org/10.13039/50110000171
Effects of cognitive distraction on chemosensory perception in volunteers with obesity
Full text linkThe aim of this thesis was to examine the relationship between cognitive distraction and chemosensory perception in the context of eating behavior, with a particular focus on odor and taste perception across individuals of varying weight statuses. In today’s fast-paced, technology-driven society, distracted eating has become prevalent, with a majority consuming a meal while being involved in other tasks (distracted). Alarmingly, evidence increasingly links such behavior with obesity and recognizes altered chemosensory perception as a possible contributing factor. However, most of the existing research is limited to normal-weight and predominantly female individuals, excluding populations with excess weight or obesity.
Addressing this gap in the existing literature, our research comprised two studies designed to investigate chemosensory responses under varying levels of cognitive distraction across weight groups and genders. Both studies employed a randomized, cross-sectional experimental design. In addition, we used the Tetris game to induce varying levels of cognitive distraction, providing a realistic and immersive representation of the dynamic nature of distractions commonly encountered in daily life.
Within the first study (N = 58) we investigated the impact of cognitive distraction on taste perception in participants with and without excess weight (see chapter 2.1, Ruda et al. 2024a). Results indicate a significant reduction in taste intensity (p = 0.017) and taste pleasantness (p = 0.022) during the high distraction condition, with individuals in the overweight/obese category exhibiting the most significant intensity changes (p = 0.01).
The second study (N = 59) expands on these findings by analyzing the impact of cognitive distraction on food-related odor perception, revealing no significant difference in odor intensity ratings across distraction levels (p = 0.903) (see chapter 2.2, Ruda et al. 2024). However, a significant reduction in odor pleasantness was observed under high distraction (p = 0.007), with a more pronounced effect in lean participants compared to those with an overweight status (p = 0.035). An interaction between gender and distraction effects on odor pleasantness was also identified.
Overall, these findings suggest that cognitive distraction indeed alters chemosensory perception in a manner that is influenced by both weight status and gender. By providing evidence for the varying impact of distraction on chemosensory processing, this thesis underscores the importance of addressing sensory and cognitive interactions in dietary interventions. These insights might contribute to more effective, tailored approaches for promoting healthier eating habits amidst a modern distraction-rich environment.Diese Arbeit untersucht den Zusammenhang zwischen kognitiver Ablenkung und chemosensorischer Wahrnehmung im Kontext des Essverhaltens, wobei der Fokus auf Geruchs- und Geschmacksempfindungen bei Personen mit unterschiedlichem Körpergewicht liegt. In der heutigen schnelllebigen, technologiegetriebenen Gesellschaft ist Essen in Kombination mit einer ablenkenden Tätigkeit weit verbreitet; ein Großteil der Menschen konsumiert Mahlzeiten, während sie gleichzeitig andere Aufgaben ausführen. Besorgniserregend ist, dass solche Verhaltensweisen zunehmend mit Fettleibigkeit in Verbindung gebracht werden und hierfür eine veränderte chemosensorische Wahrnehmung als möglicher Einflussfaktor betrachtet wird. Allerdings konzentrieren sich viele der bisherigen Studien überwiegend auf normalgewichtige, hauptsächlich weibliche Probandinnen, während Übergewicht und Adipositas oft nicht berücksichtigt werden.
Diese Arbeit schließt diese Forschungslücke durch zwei Studien, die darauf abzielen, die chemosensorischen Reaktionen unter verschiedenen Ablenkungsniveaus über unterschiedliche Gewichtskategorien und Geschlechter hinweg zu untersuchen. Beide Studien verwenden ein randomisiertes, querschnittliches experimentelles Design. Dabei wird das Tetris-Spiel genutzt, um verschiedene Grade kognitiver Ablenkung zu erzeugen und eine realistische Darstellung dynamischer Ablenkungen zu schaffen, wie sie im Alltag häufig auftreten.
In der ersten Studie (N = 58) untersuchen wir den Einfluss kognitiver Ablenkung auf die Geschmackswahrnehmung bei Teilnehmer-/innen mit und ohne Übergewicht (siehe Kapitel 2.1, Ruda et al. 2024a). Die Ergebnisse zeigen eine signifikante Reduktion der Geschmacksintensität (p = 0,017) und der Geschmacksempfindung (p = 0,022) unter hoher Ablenkung, wobei besonders Teilnehmer/-innen mit Übergewicht die stärksten Intensitätsveränderungen aufweisen (p = 0,01).
Die zweite Studie (N = 59) erweitert diese Ergebnisse und analysiert die Auswirkungen kognitiver Ablenkung auf die Wahrnehmung von nahrungsmittelbezogenen Gerüchen. Sie zeigt, dass keine signifikanten Unterschiede in der Geruchsintensität zwischen den Ablenkungsniveaus bestehen (p = 0,903) (siehe Kapitel 2.2, Ruda et al. 2024b). Allerdings wurde eine signifikante Verringerung der Geruchsempfindung unter hoher Ablenkung festgestellt (p = 0,007), wobei der Effekt bei normalgewichtigen Teilnehmer/-innen stärker ausgeprägt war als bei Teilnehmer/-innen mit Übergewicht (p = 0,035). Es wurde auch eine Wechselwirkung zwischen Geschlecht und Ablenkungseffekten auf die Geruchsempfindung identifiziert.
Insgesamt legen diese Ergebnisse nahe, dass kognitive Ablenkung die chemosensorische Wahrnehmung auf eine Weise verändert, die sowohl vom Gewicht als auch vom Geschlecht beeinflusst wird. Durch den Nachweis des unterschiedlichen Einflusses von Ablenkung auf die chemosensorische Verarbeitung unterstreicht diese Arbeit die Bedeutung der Berücksichtigung sensorischer und kognitiver Interaktionen in Ernährungsinterventionen. Die gewonnenen Erkenntnisse könnten zu individuelleren, effektiveren Ansätzen zur Förderung gesünderer Essgewohnheiten in einer modernen, von Ablenkungen geprägten Umgebung beitragen
The judicial reform in Israel and constitutional developments in the Middle East
Full text linkZusammenfassung In Zeiten politischer Veränderungen wird um Verfassungen besonders gerungen. Der Nahe Osten und Nordafrika bietet hierfür insbesondere seit den politischen Umbrüchen ab 2010 zahlreiche Beispiele. Vorliegender Beitrag zeigt zunächst die Bedeutung von Verfassungen unabhängig des Regimetypus auf und veranschaulicht, wie auch in autokratischen Ordnungen um Verfassungen gestritten wird und sie für unterschiedliche Herrschaftszwecke instrumentalisiert werden. Am Fallbeispiel der israelischen Demokratie und ihrem Ringen um eine Verfassung zeigen wir einerseits, wie das Fehlen einer Verfassung auch zu Legitimationsproblemen der de facto vorliegenden Verfassungsorgane führt. Andererseits untersuchen wir, wie sich das Ringen um die Justizreform in Israel in unterschiedliche Prozesse der Staatenbildung, Verfassungsentwicklung und politischer Umbrüche in der Region des Nahen Ostens einbetten lässt.Constitutions are particularly contested in times of political change. The Middle East and North Africa offers numerous examples with the Arab uprisings unfolding since 2010. This contribution begins by demonstrating the importance of constitutions regardless of the regime type and illustrates how constitutions are contested in autocratic orders and how they are instrumentalized for various purposes. Using the example of the Israeli democracy and its struggle for a constitution, we show on the one hand how the lack of a constitution leads to legitimation problems of the de facto constitutional bodies. On the other hand, we stress how the struggle for the judicial reform in Israel can be embedded in different processes of state-building, constitutional development and political upheaval in the Middle East.Open Access funding enabled and organized by Projekt DEAL.Friedrich-Alexander-Universität Erlangen-Nürnberg (1041
Different Nucleation Mechanisms during Atomic Layer Deposition of HfS2 on Cobalt Oxide Surfaces
Full text linkThe atomic layer deposition (ALD) of HfS2 is investigated on atomically defined CoO(100) and CoO(111) surfaces under ultrahigh‐vacuum (UHV) conditions. The ALD process is performed by sequential dosing of the precursors tetrakis(dimethylamido)hafnium (TDMAH) and deuterium sulfide (D2S) separated by purging periods. The growth and nucleation reactions are monitored by in situ infrared reflection absorption spectroscopy (IRAS). HfS2 films nucleate and grow on both cobalt oxide surfaces, despite the fact that CoO(100) lacks acidic protons and CoO(111) exposes only very few OH groups at defects. On these OH‐free or OH‐lean surfaces, the nucleation step involves a Lewis acid‐base reaction instead. The stoichiometry of the ─Hf(NMe2)x nuclei changes during the first ALD half cycle. On CoO(100), the split‐off ligands bind as ─NMe2 to surface cobalt ions. The nucleation on CoO(111) is more complex and the split‐off ligands undergo dehydrogenation to form various surface species with C═N double and C≡N triple bonds and surface OH. These findings reveal a new nucleation mechanism for ALD in the absence of acidic protons and show that other factors such as Lewis acidity, surface structure, and surface reactivity must also be considered in the nucleation event.The atomic layer deposition (ALD) of HfS2 on CoO(100) and CoO(111) surfaces under ultrahigh‐vacuum conditions involves sequential dosing of tetrakis(dimethylamido)hafnium and deuterium sulfide, monitored by infrared reflection absorption spectroscopy (IRAS). HfS2 films nucleate on both surfaces via Lewis acid–base reactions due to the absence of acidic protons, with stoichiometry changes and complex ligand chemistry observed in the first half cycle. imageFriedrich‐Alexander‐Universität Erlangen‐Nürnber
Micro-Mechanical Fracture Investigations on Grain Size Tailored Tungsten-Copper Nanocomposites
Full text linkTungsten-copper composites are used in harsh environments because of their superior material properties. This work addresses a tungsten-copper composite made of 20 wt.% copper, which was subjected to grain refinement by high-pressure torsion, whereby the deformation temperature was varied between room temperature and 400 °C to tailor the grain size. Deformation was performed up to microstructural saturation and verified by hardness measurement and scanning electron microscopy. From the refined nanostructured material, micro-cantilever bending beams with cross-sections spanning from 5 × 5 to 35 × 35 µm 2 were cut to examine possible size effects and the grain size influence on the fracture behavior. Fracture experiments were performed in situ inside a scanning electron microscope by applying a quasi-static loading protocol with partial unloading steps. Inspection of the fracture surfaces showed that all cantilevers failed in an inter-crystalline fashion. Nevertheless, remaining coarser tungsten grains impacted the resultant fracture toughness and morphology. Cantilevers fabricated from the 400 °C specimen exhibited a fracture toughness of 220 ±50 Jm2. For the room temperature cantilevers, a fracture toughness of 410 ±50 Jm2was observed, which declined to 340 ±30 Jm2for cantilevers < 10 × 10 µm 2 , confirming a size effect. The increased fracture toughness is attributed to the delamination-like structures formed in the room temperature sample.Open access funding provided by Montanuniversität Leoben.H2020 European Research Councilhttp://dx.doi.org/10.13039/100010663Montanuniversität Leobe
An “outer subarachnoid space”: fact or artifact? A commentary on “Structural characterization of SLYM– a 4th meningeal membrane” fluids and barriers of the CNS (2023) 20:93 by V. Plá et al.
Full text linkSystematic mapping of mitochondrial calcium uniporter channel (MCUC)-mediated calcium signaling networks
Full text linkThe mitochondrial calcium uniporter channel (MCUC) mediates mitochondrial calcium entry, regulating energy metabolism and cell death. Although several MCUC components have been identified, the molecular basis of mitochondrial calcium signaling networks and their remodeling upon changes in uniporter activity have not been assessed. Here, we map the MCUC interactome under resting conditions and upon chronic loss or gain of mitochondrial calcium uptake. We identify 89 high-confidence interactors that link MCUC to several mitochondrial complexes and pathways, half of which are associated with human disease. As a proof-of-concept, we validate the mitochondrial intermembrane space protein EFHD1 as a binding partner of the MCUC subunits MCU, EMRE, and MCUB. We further show a MICU1-dependent inhibitory effect of EFHD1 on calcium uptake. Next, we systematically survey compensatory mechanisms and functional consequences of mitochondrial calcium dyshomeostasis by analyzing the MCU interactome upon EMRE, MCUB, MICU1, or MICU2 knockdown. While silencing EMRE reduces MCU interconnectivity, MCUB loss-of-function leads to a wider interaction network. Our study provides a comprehensive and high-confidence resource to gain insights into players and mechanisms regulating mitochondrial calcium signaling and their relevance in human diseases.Synopsis Mitochondrial calcium uptake through the uniporter channel MCUC is critical to cell signaling, metabolism, physiology, and disease. This study provides an unbiased and quantitative map of the MCUC interactome and its remodelling, both under resting conditions and after genetic perturbations. Tandem affinity purification/mass-spectrometry-based approach identifies the MCUC protein interaction network. Mitochondrial inner membrane protein EFHD1 interacts with MCUC and inhibits mitochondrial calcium uptake. Loss of MCUB subunit results in an expansion and greater interconnection of the MCU protein network.A dynamic map of the MCUC interaction landscape reveals inhibition of mitochondrial calcium uptake by the mitochondrial intermembrane space protein EFHD1.Deutsche Forschungsgemeinschaft (DFG)http://dx.doi.org/10.13039/501100001659Helmholtz Association (亥姆霍兹联合会致力)http://dx.doi.org/10.13039/501100009318EC | Horizon Europe | Excellent Science | HORIZON EUROPE Marie Sklodowska-Curie Actions (MSCA)http://dx.doi.org/10.13039/100018694National Institute of Health Sciences (NIHS)http://dx.doi.org/10.13039/100030719Bayerisches Staatsministerium für Wissenschaft und Kunst (STMWK)http://dx.doi.org/10.13039/50110002171
Stabilization of a cyclic network of strings by nodal control
Full text linkWe consider a network of coupled strings that contains a cycle. We show that boundary feedback stabilization that uses only data of the state at boundary nodes that are not contained in the cycle is in general impossible. We demonstrate that also with control actuators that act at the interior nodes contained in the cycle with certain standard control laws that use only Neumann control action the situation does not improve and the system is still not stable. We prove that with an actuator that uses also Dirichlet control action and is located within the cycle, exponential stabilization is possible.Open Access funding enabled and organized by Projekt DEAL.Friedrich-Alexander-Universität Erlangen-Nürnberg (1041
Correction: Patient-tailored silicone plug for HeartMate 3™ left ventricular assist device explantation
Full text linkAction and performance in children’s and youth sport
No full textOpen Access funding enabled and organized by Projekt DEAL.Friedrich-Alexander-Universität Erlangen-Nürnberg (1041