Topological spin textures in synthetic antiferromagnets: stabilization, nucleation and dynamics of (Bi)merons, Skyrmions and Skyrmion–Bimeron Pairs (Skymerons)

In the emerging landscape of post-CMOS technologies, spintronics-based devices have garnered growing interest for their potential to enable non-volatile, energy-efficient, and densely integrated logic and memory technologies. Among the various strategies explored, the utilization of topologically non-trivial magnetic spin textures, such as skyrmions and bimerons, has emerged as a strong candidate for several spintronic devices owing to their nanoscale dimensions, topologically enhanced stability, and susceptibility to manipulation by electrical currents. While skyrmions in ferromagnets have enabled seminal advances in racetrack memories, logic gates, and unconventional computing concepts, their practical use is hampered by stray fields, limited thermal stability, and the intrinsic skyrmion Hall effect during dynamics. These challenges motivate the exploration of alternative topological spin textures beyond skyrmions and their realization in compensated magnetic systems, where antiparallel sublattice magnetizations cancel the net moment, suppress the skyrmion Hall effect, and enable the stabilization of spin textures over a broad range of magnetic fields suitable for device applications. This thesis addresses these challenges by establishing an experimental framework to investigate the stabilization, nucleation, and dynamics of various topological spin textures stabilized by the interfacial Dzyaloshinskii–Moriya interaction (iDMI) in synthetic antiferromagnets (SyAFMs). SyAFMs, consisting of ferromagnetic layers antiferromagnetically coupled through metallic spacers, exhibit compensated spin textures with negligible net dipolar fields. Their magnetic properties can be finely tuned via the thickness of the constituent sublattices, enabling independent control over key material parameters such as the effective perpendicular magnetic anisotropy, iDMI, and saturation magnetization. This work demonstrates the stabilization of chiral in-plane antiferromagnetic topological spin textures, namely merons, antimerons, and bimerons, by primarily tuning the net effective anisotropy of the system to achieve a nearly vanishing condition [1, 2]. Perpendicular synthetic antiferromagnetic multilayers are engineered to host skyrmions with radii of 50–100 nm that exhibit distinct static and dynamic characteristics. Element-specific pump–probe X-ray microscopy enables the sublatticeresolved nanosecond dynamic imaging of skyrmion–skyrmion interactions such as scattering, recoil, and collective flow dynamics [3]. Beyond two-dimensional spin textures, by tuning the saturation magnetization of each ferromagnetic sublattice, this thesis demonstrates a three-dimensional extension of skyrmions, referred to as hybrid skyrmion tubes [4]. Finally, this thesis introduces and experimentally realizes a new topological spin texture, termed the skymeron, which emerges from the near-orthogonal alignment of skyrmions and bimerons. Overall, these findings establish a quantitative framework for the stabilization and nucleation of various topological spin textures in synthetic antiferromagnets and demonstrate their fully reproducible collective dynamics over billions of cycles, even in the incoherent flow regime, thereby paving the way for their utilization in future spintronic devices.X, 269 Seiten ; Illustrationen, Diagramm

Can induced rumination modulate attention? An experimental approach using the attention Network Test (ANT)

The efficiency of our daily performance depends on our ability to manage cognitive resources on different levels and to select relevant information for current task demands. One phenomenon that can limit the efficiency of daily performance is intrusive, repetitive negative thoughts also known as rumination. The present online study aimed at examining the influence of induced state rumination on specific networks of attention, namely alerting, orienting and executive control. Overall, 172 participants (f = 128; m = 44; Mage = 24.97, range: 18–40 years) were randomly assigned to an experimental and a control condition and then subjected to different goal-related inductions. Before and after the inductions, participants performed the Attention Network Test (ANT) to examine potential effects of rumination on participants’ performance and rated their state rumination. Mixed ANOVAs were computed to investigate whether induced goal-related state rumination had an impact on performance in the three attentional networks. In addition, to better evaluate the results, we also applied Bayesian repeated measures ANOVA’s. Overall, results showed no effect of rumination on attention regarding performance on the ANT. We discuss the present null effects and provide starting points for future research

Vergleich von Vorspannung, Gewindereibung und Reibwert zwischen Gold- und Titanschrauben bei der Verschraubung von Zirkoniumdioxid-Implantaten und PEKK- Abutments mit unterschiedlichem Anziehdrehmoment

II, 60 Seiten ; Illustrationen, Diagramm

Does Ramadan fasting influence time-motion metrics and psychophysiological responses in soccer players during small-sided games performed in fed and fasted states?

We explored how Ramadan fasting (RF) influences GPS-derived time-motion metrics and psychophysiological responses in soccer players during small-sided games (SSG). Twelve semi-professional male players (mean age 21.1 ± 0.7 y; estimated V ̇ O2max 54.5 ± 2.2 mL/min/kg) participated in four experimental SSG sessions in a within-subject, counterbalanced design. These sessions were scheduled at 15:00 and 21:00 before Ramadan, in a fed state (i.e., BR15fed and BR21fed), and during the fourth week of Ramadan at 15:00 in a fasted state (DR15fasted) and at 21:00 in a fed state (DR21fed). Sleep patterns, dietary intake, and insomnia symptoms were evaluated during the week preceding and final week-of-Ramadan. Participants’ Hooper index (wellness) and daytime sleepiness and mood measures were assessed before each session. Time-motion metrics using GPS and exercise heart rate (HR) were assessed during all sessions, and ratings of perceived exertion (RPE) were collected after each session. Except for a higher number of decelerations in DR21fed session (p < 0.001), RF had no significant effect on other time-motion metrics. Absolute and relative exercise HR were higher at BR15fed than at BR21fed and at DR15fasted. RPE, Hooper index scores, and perceptual stress and muscle soreness components were higher at DR15fasted compared to BR15fed. Additionally, RF was associated with decreased sleep duration (by ~45 minutes) and increased insomnia symptoms and daytime sleepiness, while mood states and dietary intake were unchanged. RF induced physiological and perceptual changes in response to exercise, particularly in the fasted state. However, SSG performance metrics remained stable, suggesting fasted athletes can maintain short-duration SSG performance regardless of fasting status

Natural product-like fragments unlock novel chemotypes for a kinase target─exploring options beyond the flatland

In this study, we utilized a high-performance soaking system of protein kinase A (PKA) to perform a crystallographic screening of a natural product-like fragment library. We resolved 36 fragment-bound structures, corresponding to a hit rate of 41%. Nine fragments bound within the ATP site, nine peripherally, and 18 interacted with both the ATP and peripheral sites. One fragment binds to the same site as the approved allosteric kinase inhibitor asciminib, while another induces an unexpected conformational change. Systematic database mining revealed that both the fragments and their natural product parents have not been previously associated with PKA or kinase activity. A scaffold/chemotype analysis further underscored their novelty. Cheminformatics analyses confirmed that these fragments occupy a distinct chemical space, enriched in saturation, spatial complexity and molecular three-dimensional character compared to kinase binders from reference data sets. These properties have previously been linked to increased selectivity, reduced CYP450 inhibition, and higher overall clinical success rates

Archetypische Muster von Gesichtsfeldausfällen in der Oktopus-Perimetrie: klinische Korrelate und Struktur-Funktions-Analyse

IV, 100 Seiten ; Illustrationen, Diagramm

The ISIMIP groundwater sector : a framework for ensemble modeling of global change impacts on groundwater

Groundwater serves as a crucial freshwater resource for people and ecosystems, playing a vital role in adapting to climate change. Yet, its availability and dynamics are affected by climate variations, changes in land use, and abstraction. Despite its importance, our understanding of how global change will influence groundwater in the future remains limited. Multi-model ensembles are powerful tools for impact assessments; compared to single-model studies, they provide a more comprehensive understanding of uncertainties and enhance the robustness of projections by capturing a range of possible outcomes. However, to date, no ensemble of groundwater models has been available to assess the impacts of global change. Here, we present the new Groundwater sector within ISIMIP, which combines multiple global, continental, and regional-scale groundwater models. We describe the rationale for the sector, the sectoral output variables that underpinned the modeling protocol, and showcase current model differences and possible future analysis. Currently, eight models are participating in this sector, ranging from gradient-based groundwater models to specialized karst recharge models, each producing up to 19 out of 23 modeling protocol-defined output variables. To showcase the benefits of a joint sector, we utilize available model outputs of the participating models to show the substantial differences in estimating water table depth (global arithmetic mean 6–127 m) and groundwater recharge (global arithmetic mean 78–228 mm yr−1), which is consistent with recent studies on the uncertainty of groundwater models, but with distinct spatial patterns. We further outline synergies with 13 of the 17 existing ISIMIP sectors and specifically discuss those with the global water and water quality sectors. Finally, this paper outlines a vision for ensemble-based groundwater studies that can contribute to a better understanding of the impacts of climate change, land use change, environmental change, and socio-economic change on the world's largest accessible freshwater store – groundwater

Untersuchung klinischer Zeichen, laborchemischer Werte und Scores zur präoperativen Differenzierung zwischen einer unkomplizierten und einer komplizierten Appendizitis

6.1.1 Einleitung Die präoperative Unterscheidung zwischen unkomplizierter und komplizierter Appendizitis ist klinisch bedeutsam, da konservative Therapiekonzepte zunehmend diskutiert werden. Bisher fehlen jedoch verlässliche Parameter zur sicheren Differenzierung (1). 6.1.2 Methoden In einer multizentrischen, retrospektiven Kohortenstudie wurden 1.909 operierte Patienten mit akuter Appendizitis aus 41 deutschen Kliniken während der Covid-19 Pandemie analysiert. Negative Appendektomien wurden deskriptiv ausgewertet. Der Fokus lag auf klinischen Zeichen, Laborwerten und etablierte Scores. Die statistische Analyse umfasste univariate Tests, ROC-Analysen und multivariable logistische Regression. 6.1.3 Ergebnisse Von den eingeschlossenen Patienten hatten 33,2 % eine unkomplizierte und 61,1 % eine komplizierte Appendizitis. Komplizierte Verläufe wurden häufiger bei Männern, älteren sowie multimorbiden Patienten beobachtet. Klassische klinische Zeichen wie das Blumberg-, Lanz- oder McBurney-Zeichen waren bei komplizierter Appendizitis zwar häufiger positiv, erreichten jedoch nur geringe Diskriminationswerte (AUC 0,53–0,60). Der Modified Alvarado Score lag bei komplizierten Verläufen höher (OR 1,35 pro Punkt) und wies eine AUC von 0,67 auf. Die Leukozytenzahl (OR 1,12; AUC 0,66) und das CRP (OR 1,004; AUC 0,68) zeigten ebenfalls signifikant höhere Werte bei komplizierten Fällen, allerdings mit begrenzter Trennschärfe. Procalcitonin erreichte in der Subgruppe eine AUC von 0,74, konnte aufgrund der geringen Fallzahl (n = 77) jedoch nicht weiter abgesichert werden. In der multivariablen Analyse bestätigten sich Geschlecht, Alter, Leukozytenzahl und der Modified Alvarado Score als unabhängige Prädiktoren; die erklärte Varianz des Modells blieb jedoch insgesamt gering. 6.1.4 Schlussfolgerung Weder klinische Zeichen noch Laborwerte oder etablierte Scores ermöglichen eine zuverlässige präoperative Differenzierung zwischen unkomplizierter und komplizierter Appendizitis. Damit sind sie für therapeutische Entscheidungen allein nicht ausreichend. Die Ergebnisse unterstreichen die Notwendigkeit integrativer diagnostischer Ansätze, die Bildgebung und klinische Befunde zu kombinieren.6.2.1 Introduction Differentiating uncomplicated from complicated appendicitis before surgery is clinically relevant, as conservative treatment options are increasingly considered. However, reliable diagnostic markers are still lacking(1). 6.2.2 Methods In a multicenter, retrospective cohort study, 1,909 patients who underwent surgery for acute appendicitis across 41 German hospitals during the COVID-19 pandemic were analyzed. Negative appendectomies were evaluated descriptively. The focus was placed on clinical signs, laboratory values, and established clinical scores. Statistical analyses included univariate testing, ROC curve analyses, and multivariable logistic regression. 6.2.3 Results Among the included patients, 33.2% presented with uncomplicated and 61.1% with complicated appendicitis. Complicated cases occurred more frequently in male, older, and multimorbid patients. Classical clinical signs such as Blumberg’s, Lanz’s, or McBurney’s sign were more often positive in complicated disease but demonstrated only limited discriminatory capacity (AUC 0.53–0.60). The Modified Alvarado Score was significantly higher in complicated cases (OR 1.35 per point) with an AUC of 0.67. Leukocyte count (OR 1.12; AUC 0.66) and CRP (OR 1.004; AUC 0.68) were also elevated in complicated cases, although their diagnostic performance remained modest. Procalcitonin yielded an AUC of 0.74 in the subgroup analysis but could not be reliably assessed due to the small sample size (n = 77). In multivariable logistic regression, sex, age, leukocyte count, and the Modified Alvarado Score emerged as independent predictors, although the overall explanatory power of the model remained limited. 6.2.4 Conclusion Neither clinical signs, nor laboratory parameters, nor established scoring systems provide sufficient accuracy for reliable preoperative differentiation between uncomplicated and complicated appendicitis. These findings highlight the need for integrative diagnostic approaches combining imaging, clinical assessment, and advanced algorithm-based tools.71 Seiten : Illustrationen, Diagramm

Trio-sequencing reveals high germline mutation rates in the Colorado potato beetle (Leptinotarsa decemlineata)

Germline mutation rates are fundamental to evolution, yet they remain unquantified for beetles (Coleoptera), the most speciose order including major pests. We sequenced genomes from 16 trios of the Colorado potato beetle (Leptinotarsa decemlineata, CPB)—a pest that has evolved resistance to many insecticides. We estimated a germline mutation rate of 5.8 × 10−9 (95% CI: 4.7 × 10−9, 7.2 × 10−9) per site per generation in CPB, a rate 2-fold higher than the median for other insects. Across 13 insect species, mutation rate was positively associated with genome-wide GC content (PGLS). The increased mutation rate in CPB is also consistent with drift-barrier expectations. Based on this mutation rate and the beetle’s fecundity, we estimate that the brood from just one CPB female can introduce nearly 141 new mutations into the coding regions each generation. These findings inform CPB’s rapid pesticide resistance evolution and fill a key gap in arthropod genomics and evolution

Use of antibiotics for prevention and treatment of sinus lift infections : an umbrella review of systematic reviews and meta-analyses

Background Antibiotic use in sinus floor elevation (SFE) procedures remains controversial due to heterogeneous protocols and inconsistent clinical outcomes. Aim To evaluate the effectiveness of systemic antibiotic regimens for the prevention and management of infections associated with SFE procedures, based on a synthesis of existing systematic reviews and meta-analyses. Methods The study protocol was registered in the PROSPERO (CRD420251061400). Seven systematic reviews and meta-analyses (2008–2024) were included. Methodological quality was appraised using AMSTAR-2, overlap among primary studies was evaluated with the GROOVE tool, and certainty of evidence was assessed through the GRADE approach. A descriptive synthesis was performed, as methodological heterogeneity and overlap precluded meta-analytic pooling. Results Infection rates following SFE ranged from 0.3% to 11.6%, with implant survival consistently above 90% regardless of antibiotic regimen. Prophylactic antibiotics were commonly prescribed (Amoxicillin or Amoxicillin/Clavulanate, 7–10 days), although no standardized protocol was identified. Reviews rated as high or moderate quality provided limited yet consistent evidence suggesting that antibiotics may reduce infection risk in high-risk situations (e.g., membrane perforation, extensive lateral approach, or systemic comorbidities). The overall certainty of evidence was low to very low. Conclusions Current evidence suggests that antibiotic prophylaxis may be beneficial only in selected high-risk scenarios, whereas routine use appears unnecessary in uncomplicated SFE. Given the low certainty and heterogeneity of existing studies, recommendations should be interpreted cautiously, and future well-designed randomized trials are needed to define standardized antibiotic and non-antibiotic strategies for infection prevention