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Use of antibiotics for prevention and treatment of sinus lift infections : an umbrella review of systematic reviews and meta-analyses
No full textBackground
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
Biased judgment or lack of skill? The role of news consumption in (mis)information identification in the context of Russia’s war against Ukraine
Full text linkThis study examines how media consumption shapes individuals’ ability to distinguish true from false information and their response biases in the context of Russia’s invasion of Ukraine. Drawing on signal detection theory, it analyzes sensitivity (the ability to discern truth from falsehood) and absolute response bias (the strength of the tendency to accept or reject claims) separately. Data come from a survey conducted in 19 European and American countries (N = 19,037) in 2022 during Russia’s full-scale war against Ukraine. Reliance on newspapers is linked to higher sensitivity for both pro- and anti-Russia statements, whereas television news shows no such effect. Social media use is unrelated to sensitivity, but corresponds with more balanced evaluations, while messenger-based news consumption predicts lower sensitivity and stronger biases. In some cases, alternative media use is also associated with increased response bias. Cross-national comparisons show that press freedom is linked to higher sensitivity to pro-Russia claims and to asymmetric response biases for pro- and anti-Russia frames, consistent with dominant media narratives
Linking the microstructural characteristics of mortar specimens involving non-ureolytic bacteria and their strength properties
Full text linkSystemic inflammation in retinal vein occlusion and its role in clinical outcomes of secondary macular edema
Full text linkObjectives: This study aims to analyze the association between systemic inflammation and clinical outcomes in patients with macular edema secondary to retinal vein occlusion (RVO). Methods: A retrospective analysis of 68 patients with acute RVO, in whom cardiovascular risk factors were assessed, was conducted. Laboratory determinations included levels of C-reactive protein (CRP) and homocysteine to explore the systemic inflammatory status. Optical coherence tomography (OCT) parameters and visual acuity (LogMAR) were collected at baseline. Follow-up visual acuity was determined after 12 months. The number of intravitreal anti-VEGF injections and the performed laser treatment were assessed after 12 and 24 months. Associations of inflammatory markers with clinical outcomes were analyzed by correlation analysis, and patients with or without evidence for inflammation were compared. Results: At baseline, the mean foveal retinal thickness (FRT) was 591 ± 277 µm, the mean average central retinal thickness (CRT) was 580 ± 227 µm, and the mean average central retinal volume (CRV) was 12 ± 3 mm3. The level of CRP at baseline was significantly associated with increased FRT, average CRT, and average CRV (p = 0.024; p = 0.027; p = 0.003). CRP levels were also associated with a lower BCVA at baseline and after 12 months (p = 0.018; p = 0.006). In patients with elevated homocysteine levels, a trend towards a higher number of required laser treatments was observed. No association between increased inflammatory parameters and the number of required intravitreal injections was detected. Conclusions: Systemic inflammation is associated with the severity of macular edema secondary to RVO. CRP concentrations could represent a prognostic marker for the course of the patient’s visual acuity
Untersuchung klinischer Zeichen, laborchemischer Werte und Scores zur präoperativen Differenzierung zwischen einer unkomplizierten und einer komplizierten Appendizitis
No full text6.1.1 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
All-Food-Sequencing: Identification and quantification of food ingredients by whole-genome metagenomics
No full textAll-food sequencing (AFS) is a non-targeted, whole-genome DNA-based screening method for simultaneous qualitative and quantitative species diagnosis in complex foods. No a priori knowledge or primers are required, and a single analysis can potentially detect animal and plant components as well as fungi, bacteria, and other accompanying microbiota.
Quantitative performance of AFS was evaluated using controlled calibration samples, including defined meat and fish mixtures. In direct comparison with established assays, AFS delivered quantification that outperformed conventional qPCR and matched ddPCR, while retaining a key practical advantage: broad, primer-independent screening and quantification of multiple ingredients within a single workflow, rather than many separate target specific assays. The calibration series also identified two systematic factors that influence quantitative accuracy. First, differences in genome size can shift read proportions, but this bias was shown to be correctable by genome size normalization. Second, matrix effects of the food composition can alter DNA extraction yield between ingredients, so the highest quantitative agreement is achieved with matrix-specific calibration - a constraint shared by all DNA-based methods.
Application for real food products showed how AFS behaves under practical conditions with regard to heterogeneity and incomplete or inaccurate labelling of species components. Doner kebab samples showed significant deviations and several cases in which the predominant meat type did not correspond to the advertised expectation. In addition, other ingredients were detected that suggest unintentional admixture or deliberate substitution. In the case of seafood and surimi products, the declared main ingredients were generally confirmed. In addition, the analysis revealed undeclared taxa, including additional seafood and plant components in mixed dishes, some with potential allergen relevance. Beyond the main ingredient composition, AFS provided early warning signals, including allergen-relevant plant admixtures and microbial patterns that indicate incipient spoilage.
The analysed samples also revealed practical limitations of AFS that are crucial for regulatory surveillance: ambiguous classification within closely related species, dependence on reference genomes, and the need to interpret low-level findings conservatively and verify them with targeted follow-up measures. Specificity of read classification was improved by both algorithm choice and sequencing technology. K-mer-based classification and database partitioning enabled screening against significantly larger genome reference collections. In a comparison between Illumina short reads and Oxford Nanopore long reads on calibration sausages, long-read sequencing improved quantification accuracy and reduced the number of false-positives despite higher error rates in long read, as longer reads provide more discriminative information for resolving conserved regions that otherwise drive ambiguous classification.
AFS shows the potential to provide reliable formulation information and cross-domain early warning signals as a universal, primer-free WGS screening method, provided that reference dependency and taxonomic ambiguity are recognized as current limitations and integrated into the decision on verification or follow-up measures. Therefore, it is promising for routine screening in official food monitoring in the future.xii, 193 Seiten ; Illustrationen, Diagramm
JustRelax.jl : a Julia package for geodynamic modeling with matrix-free solvers
No full textJustRelax.jl is an open-source, highly portable, and high-performance Julia (Bezanson et al., 2017) package designed for geodynamic modeling. It employs the Accelerated Pseudo-Transient (APT) (Räss et al., 2022) method to solve the Stokes and diffusion equations, making it well-suited to exploit Graphics Processing Units (GPUs).
JustRelax.jl incorporates a wide range of features critical to computational geodynamics, including complex and highly non-linear rheologies, free surface, and a particle-in-cell method to advect material information. Several of the features available in JustRelax.jl are outsourced to specialized external packages, reducing the core code base, and improving maintainability and reusability
The ISIMIP groundwater sector : a framework for ensemble modeling of global change impacts on groundwater
Full text linkGroundwater 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
GeLb-DIng: Gemeinsam Lehrpersonen bilden - Digitalität mit Informatik nachhaltig gestalten : Abschlussbericht
No full text173 Seite
Topological spin textures in synthetic antiferromagnets: stabilization, nucleation and dynamics of (Bi)merons, Skyrmions and Skyrmion–Bimeron Pairs (Skymerons)
No full textIn 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