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Harnessing orbital Hall effect in spin-orbit torque MRAM
Get PDFSpin-Orbit Torque (SOT) Magnetic Random-Access Memory (MRAM) devices offer improved power efficiency, nonvolatility, and performance compared to static RAM, making them ideal, for instance, for cache memory applications. Efficient magnetization switching, long data retention, and high-density integration in SOT MRAM require ferromagnets (FM) with perpendicular magnetic anisotropy (PMA) combined with large torques enhanced by Orbital Hall Effect (OHE). We have engineered a PMA [Co/Ni]3 FM on selected OHE layers (Ru, Nb, Cr) and investigated the potential of theoretically predicted larger orbital Hall conductivity (OHC) to quantify the torque and switching current in OHE/[Co/Ni]3 stacks. Our results demonstrate a ~30% enhancement in damping-like torque efficiency with a positive sign for the Ru OHE layer compared to a pure Pt layer, accompanied by a ~20% reduction in switching current for Ru compared to pure Pt across more than 250 devices, leading to more than a 60% reduction in switching power. These findings validate the application of Ru in devices relevant to industrial contexts, supporting theoretical predictions regarding its superior OHC. This investigation highlights the potential of enhanced orbital torques to improve the performance of orbital-assisted SOT-MRAM, paving the way for next-generation memory technology
The validation of the Nomophobia Questionnaire using a modern psychometric approach : an item response theory analysis of 5087 participants
Get PDFNomophobia, or the anxiety of being separated from one's mobile phone, is an emerging psychological condition in our digital age. The 20-item Nomophobia Questionnaire (NMP-Q) was developed to assess nomophobia symptoms. This study utilized item response theory (IRT) and classical test theory (CTT) methods to evaluate the NMP-Q's psychometric properties. Data were collected from 5087 adults who completed the NMP-Q. The CTT analyses included the computation of correlation coefficients, including McDonald's ω, Cronbach's α, Guttman's λ2, Guttman's λ6, greatest lower bound, average interitem correlation, Feldt–Gilmer coefficient, Feldt–Brennan coefficient, and Raju's β. IRT analyses included graded response modeling of items, test information function, differential item functioning, and reliability. CTT analysis revealed high reliability coefficients across nine metrics and a four-factor model with good fit indices. IRT analysis showed a strong item fit to the polytomous graded model, indicating the questionnaire's robustness. Based on IRT (both uni- and multidimensional IRT) analyses, we propose a 10-item short version (NMP-Q Short), demonstrating high correlation (r = 0.97) with the original NMP-Q. Our findings provide very good support for the NMP-Q's reliability and construct validity. The items displayed good discrimination and difficulty parameters. The second 10 items of the NMP-Q appeared to be the most informative. The proposed NMP-Q Short offers a valuable option for efficient/rapid and accurate screening. However, additional validation and sensitivity testing are warranted to further establish its usefulness
Zusammenhang von neuropsychiatrischen Symptomen bei Patienten mit kognitiver Beeinträchtigung und Demenz und biopsychologischem Stress im Alltag pflegender Angehöriger: eine explorative, ambulante Assessment-Studie
Get PDF123 Seiten ; Illustratione
Einfluss von Glukose- und Insulinmetabolismus auf die kardio-renale Achse bei Herzinsuffizienz
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Veränderung der begleitenden Trikuspidalklappeninsuffizienz nach interventioneller Edge-to-Edge Mitralklappenrekonstruktion und Einfluss auf die Langzeitprognose
Get PDFV, 66 Seiten ; Illustrationen, Diagramm
Römischer Weinbau an der Nahe und in Rheinhessen
Get PDFAusgehend von der Publikation „Weinkultur und Weingeschichte an Rhein, Nahe und Mosel“ (hrsg. von Michael Matheus, 2019) untersucht die vorliegende Studie den römischen Weinbau an der Nahe und in Rheinhessen mit besonderem Blick auf den seit 2025 archäologisch gesicherten Weinkelterfund von Odernheim am Glan. Dieser Befund stellt einen entscheidenden Beleg für die früheste Phase des Weinbaus in dieser Region und damit für die Anfänge der deutschen Weingeschichte dar. Durch die Verbindung archäologischer, historischer, archäobotanischer und kulturgeographischer Analyseansätze werden die Grundlagen einer römischen Weinkultur in den Weinbaugebieten von Nahe und Rheinhessen neu bewertet und in ihren langfristigen kulturellen und wirtschaftlichen Kontinuitätslinien betrachtet.7 Seite
Mechanophoric hydrogels : when mechanical stress produces useful responses
Get PDFMechanophoric hydrogels undergo visible color changes or alterations in optical properties in response to mechanical stimuli. Achieving mechanophoric features in hydrogel materials involves careful control of the polymer microstructure, as well as the incorporation of mechanoresponsive molecular entities known as mechanophores. Upon mechanical activation, mechanophores undergo reversible or irreversible molecular rearrangements, leading to a visual response. This review serves as a practical reference for selecting and designing mechanophores, and classifies their mode of action. By consolidating key information on molecular and materials design criteria, it focuses specifically on mechanophoric responses within hydrogel networks and provides insight into pioneering contributions, as well as some of the most recent advances and literature examples. The multidisciplinary nature of this rapidly growing research field requires expertise in organic synthesis, physical polymer chemistry and photophysics, making this review a valuable resource for researchers interested in the fundamental developments or applications of mechanophoric hydrogel materials
Prediction of protein interactions with function in protein (de-)phosphorylation
Get PDFProtein–protein interactions (PPIs) form a complex network called “interactome” that regulates many functions in the cell. In recent years, there is an increasing accumulation of evidence supporting the existence of a hyperbolic geometry underlying the network representation of complex systems such as the interactome. In particular, it has been shown that the embedding of the human Protein-Interaction Network (hPIN) in hyperbolic space (H2) captures biologically relevant information. Here we explore whether this mapping contains information that would allow us to predict the function of PPIs, more specifically interactions related to post-translational modification (PTM). We used a random forest algorithm to predict PTM-related directed PPIs, concretely, protein phosphorylation and dephosphorylation, based on hyperbolic properties and centrality measures of the hPIN mapped in H2. To evaluate the efficacy of our algorithm, we predicted PTM-related PPIs of ataxin-1, a protein which is responsible for Spinocerebellar Ataxia type 1 (SCA1). Proteomics analysis in a cellular model revealed that several of the predicted PTM-PPIs were indeed dysregulated in a SCA1-related disease network. A compact cluster composed of ataxin-1, its dysregulated PTM-PPIs and their common upstream regulators may represent critical interactions for disease pathology. Thus, our algorithm may infer phosphorylation activity on proteins through directed PPIs
Structured reporting in sleep medicine
Get PDFBackground/Objectives: Somnological findings are often written as free texts, supported by questionnaires. The quality and structure of free-text reports (FTRs) vary between examiners and specialties, depending on the individual level of expertise and experience in sleep medicine. This study aimed to compare the quality of free-text reports (FTRs) and structured reports (SRs) from somnological consultations in otolaryngology for patients assessed for obstructive sleep apnea (OSA). Methods: This study compared free-text reports (FTRs) and structured reports (SRs) from 50 patients with suspected OSA, including medical history, clinical examination findings, and medical letters, all prepared by six examiners with similar experience levels. A web-based approach was used to develop a standardized template for structured somnological reporting. The completeness and time required for both FTRs and SRs were evaluated, and a questionnaire was administered to assess user satisfaction with each reporting method. Results: The completeness scores of SRs were significantly higher than those of FTRs (88% vs. 54.2%, p < 0.001). The mean time to complete an SR was significantly shorter than that for FTRs (10.2 vs. 16.8 min, p < 0.001). SRs had significantly higher user satisfaction compared to FTRs (VAS 8.3 vs. 2.2, p < 0.001). Conclusions: Compared to FTRs, SRs for OSA patients are more comprehensive and faster. The use of SR is more satisfactory for examiners and supports the learning effect
Investigation of influences of air mass transport and chemical processes on the trace substance distribution in the lower atmosphere using chemical ionization mass spectrometry and a self-developed measurement drone
Get PDFThe distribution of trace substances in aerosol and gas phase varies with sources, transport mecha-nisms, and sinks, and influences air quality, and Earth’s climate. A deeper understanding of mete-orological influences on chemical processes is crucial to establish policies preventing hazards caused by humans and affecting them.
In this work, measurement devices and methods were developed to investigate chemical and mi-crophysical processes affecting trace substances and their distribution. A thermo desorption tech-nique for gases and aerosol particles for chemical analysis was developed as a complementary of-fline analysis method for an aerosol sampler that can collect aerosol and gas phase samples sepa-rately, differentiating depending on composition of the advected air. It was applied in-field near a wood‑fired pizza oven to investigate cooking emissions. The separated aerosol phases were ana-lyzed by chemical ionization mass spectrometry to identify characteristic cooking and bio-mass‑burning markers. The second developed device is the research measurement drone FLab (“Flying Laboratory”) to extend ground-based in-situ measurements into the vertical dimension to investigate transport of air masses in the planetary boundary layer (PBL). FLab was designed to measure the key variables relevant to tropospheric microphysical and chemical processes: wind, temperature and humidity, O3, CO2 and aerosol particle number concentration, size distribution, and black carbon concentrations. FLab was deployed in two 2.5-week long field campaigns in conti-nental Germany (BISTUM23 and BISTUM24). A case study demonstrates successful bridging of ground-based and airborne-based measurements. During BISTUM23, particle-phase samples were collected at multiple heights throughout the day, while FLab continuously profiled the vertical 500 m-range. Combining FLab data with external targeted and non‑targeted analyses of the particle phase’s chemical composition revealed oxidation and transport processes of biogenic and anthro-pogenic compounds and the general aerosol composition, respectively.
Across both campaigns, near‑hourly diurnal vertical profiling with FLab allowed detection of mixing layers in the lower troposphere. During nighttime, on average pollutant markers were more sensi-tive mixing layer height (MLH) tracers than meteorological variables; notably, specifically O3 and the potential temperature were overall the most effective markers. The dataset from 383 flights to 500 m above ground was used to evaluate how representative ground-based measurements are for the whole mixing layer. Meteorological variables are most reliably estimated with ground-based stations, while the distribution of pollutant markers was more affected by irradiance or local air mass advection, requiring vertical measurement to better characterize pollutant distribution and estimate representative pollutant concentrations. The influence of two synoptic frontal events on the local pollutant distribution in the PBL was analyzed by combining model analysis, drone-borne and ground-based measurements. Frontal events strongly influence air mass dynamics and the MLH which turns out to simultaneously influence local chemical processes due to oxidant depletion and entrainment in different altitudes. Synoptic air mass transport also altered the chemical com-position of air at the BISTUM24 measurement site as “marine-anthropogenic” influenced air led to significantly enhanced amounts of chlorine-containing species. Here, first-time reported tropo-spheric diel cycle of ClONO2 indicate high amounts of nighttime ClO radicals. Enhanced concentra-tions of ClNO2 and Cl2 after dawn suggest vertical mixing in the PBL, while high HOCl levels show significant contribution to primary OH radical production, especially in the morning.Die Verteilung von Spurenstoffen wie Aerosolpartikel und Gase in der Atmosphäre variiert je nach Quellen, Transportmechanismen und Senken. Sie beeinflusst dabei die Luftqualität und das Klima der Erde. Ein tieferes Verständnis für meteorologische Einflüsse auf chemische Prozesse ist not-wendig, um Maßnahmen zur Prävention menschengemachter Gefahren einzuführen.
In dieser Arbeit wurden mehrere Messgeräte und -methoden entwickelt, um chemische und mik-rophysikalische Prozesse zu untersuchen, die das Auftreten und die Verteilung von Spurenstoffen beeinflussen. Zunächst wurde eine offline-Analysemethode zur chemischen Analyse von Gas- und Aerosolproben entwickelt, die auf Proben eines Aerosolsammlers angewandt wurde. Dieser kann zwischen verschiedenen Luftmassen unterscheiden und wurde in der Nähe eines Pizzaofens ein-gesetzt um Emissionen von Kochprozessen zu untersuchen. Mittels dieser Thermodesorption-Methode für chemische Ionisations-Massenspektrometrie wurden charakteristische Marker für Kochprozesse und die Verbrennung von Biomasse des gesammelten Aerosols identifiziert. Die For-schungsdrohne FLab („Flying Laboratory“) wurde entwickelt um bodengestützte durch vertikale Messungen in die planetare Grenzschicht (PBL) zu erweitern und um die für troposphärische mik-rophysikalische und chemische Prozesse relevanten Größen zu messen: Wind, Temperatur und Feuchte, O3, CO2 und Aerosolpartikelanzahlkonzentration, -Größenverteilung und Rußkonzentrati-onen. FLab wurde in zwei 2,5-wöchigen Feldmesskampagnen in Süd- und Mitteldeutschland (BIS-TUM23 und BISTUM24) eingesetzt. Ein Fallbeispiel zeigt ein erfolgreiches Verknüpfen von boden-gestützte und Flugzeugmessungen. Um die chemische Zusammensetzung von Aerosolpartikeln in der PBL zu messen, wurde ein extern entwickelter Aerosolsammler eingesetzt und auf weiteren Drohnen montiert. Während BISTUM23 wurden tagesüber Partikelproben in verschiedenen Höhen gesammelt, während FLab kontinuierlich vertikale Messflüge bis in 500 m Höhe durchführte. Die Kombination dieser Messmethoden zeigt Tagesgänge der Oxidations- und Transportprozesse bio-gener und anthropogener Partikelbestandteile.
Nahezu stündliche Vertikalprofile mit FLab ermöglichten die Identifikation von Mischschichten in der unteren Troposphäre. Während der Nacht waren Schadstoffmarker zuverlässigere Indikatoren für die Mischschichthöhe (MLH) als meteorologische Messgrößen, wobei insbesondere O3 und die potentielle Temperatur am verlässlichsten im Erfassen von Grenzschichten waren. Der Datensatz von 383 Flügen bis zu 500 m Höhe wurde verwendet, um zu untersuchen, wie repräsentativ bo-dengestützte Messungen für die gesamte Mischschicht sind. Meteorologische Messgrößen konn-ten mit bodengestützten Stationen am zuverlässigsten bestimmt werden, während die Verteilun-gen von Schadstoffen stärker von der Sonneneinstrahlung oder der lokalen Luftmassenadvektion beeinflusst wurden. Der Einfluss zweier synoptischer Fronten auf die lokale Schadstoffverteilung in der PBL wurde durch die Kombination von Modellanalysen, drohnengestützten und bodengestütz-ten Messungen analysiert. Fronten beeinflussen die Luftmassendynamik und die MLH stark, was sich gleichzeitig auf lokale chemische Prozesse durch den Abbau von O3 sowie dessen Eintrag in verschiedenen Höhen auswirkt. Der synoptische Luftmassentransport veränderte auch die chemi-sche Zusammensetzung der Luft während BISTUM24, als „maritim-anthropogen“ beeinflusste Luft zu deutlich erhöhten Konzentrationen an chlorhaltigen Spezies führte, wobei erstmalig in der Tro-posphäre gemessenes ClONO2 auf hohe ClO-Radikalkonzentrationen während der Nacht hindeu-tet. Erhöhte ClNO2- und Cl2-Konzentrationen nach dem Sonnenaufgang implizieren eine vertikale Durchmischung der PBL, während zeitgleich die Photolyse von HOCl einen signifikanten Beitrag zur primären Produktion von OH-Radikalen zeigt.VIII, 248 Seiten ; Illustrationen, Diagramm