Freudenberg (Germany)

Zusammenfassung Die unterminierende Resorption der zweiten oberen Milchmolaren durch die Sechsjahrmolaren führt häufig vom Patienten unerkannt zu einem sekundären Engstand innerhalb der Stützzone. Rechtzeitig erkannt kann häufig ein frühzeitiger Verlust des zweiten Milchmolaren durch transversale Erweiterung des Oberkiefers und/oder Distalisation der oberen ersten Molaren verhindert werden. Anhand von 4 Fallvorstellungen werden verschiedene Therapieoptionen vorgestellt. Diese sind Fall 1: Distalisation mit einer Teil-Bracketapparatur; Fall 2: transversale Erweiterung mit einer semirapiden, herausnehmbaren Gaumennahtapparatur (Bioplate); Fall 3: transversale Erweiterung und Distalisation mit einer gedruckten Gaumennahtapparatur mit Distalisierungsarmen; Fall 4: Distalisation mit Alignern und okklusalem Attachement. Zusätzlich wird die Ursache der unterminierenden Resorption diskutiert, die ja häufig in einem posterioren Engstand und transversaler Unterentwicklung des Oberkiefers zu suchen ist. Wie wir den dahinterliegenden Ursachen für die Fehlentwicklung mit der gleichzeitigen Behandlung von Form und Funktion (mykie=myofunktionelle Kieferorthopädie) gerecht werden, wird am Rande erläutert.

The adoption of PEM fuel cells for heavy-duty applications, such as maritime transport, often necessitates the use of liquid hydrogen carriers like methanol due to storage and handling considerations.[1] Methanol reforming is an efficient method to generate hydrogen and CO₂ on-site; however, trace amounts of CO invariably remain in the reformate gas, despite subsequent purification steps such as water-gas shift and selective oxidation.[2,3] These residual CO levels, typically in the low ppm range, significantly exceed the tolerance threshold of platinum-based catalysts on the anode (<0.2 ppm),[4] resulting in catalyst poisoning and diminished cell performance. To address this, RuPt alloy nanoparticles supported on carbon are frequently employed for their enhanced tolerance to CO under reformate conditions.[3] Nevertheless, operational challenges arise as Ruthenium (Ru) leaches from the anode catalyst during prolonged use. This Ru migrates through the membrane and deposits on the cathode, poisoning the Pt/C catalyst and severely inhibiting oxygen reduction reaction (ORR) activity.[3,5]Efforts to mitigate Ru leaching have focused on modifying catalyst surface composition and structure. However, because Ru leaching is a long-term phenomenon, accelerated stress tests (ASTs) are essential for investigating this behavior in a practical timeframe. Traditional MEA-based ASTs, while effective, are hindered by high material requirements, long preparation times, and elevated costs, making them less suitable for early-stage catalyst screening. Additionally, quantifying the total amount of Ru leached has remained a significant challenge.In this study, we developed a robust, material-efficient AST protocol using the rotating disk electrode (RDE) to quantitatively evaluate Ru leaching. Three commercial RuPt catalysts with Ru:Pt atomic ratios of 1:1, 1.5:1, and 2:1 were examined, along with a heat-treated 2:1 ratio catalyst with larger particle size and reduced electrochemical surface area (ECSA). The RDE-based AST involved cyclic voltammetry to simulate catalyst aging, with key parameters such as cycle number (100–1000), scan rate (10–100 mV s⁻¹), and upper potential limit (0.8–0.9 V_RHE) systematically varied. Ru dissolution was quantified using inductively coupled plasma optical emission spectroscopy (ICP-OES) from collected electrolyte samples (0.1M H₂SO₄), and changes in catalyst surface composition were assessed through shifts in CO-oxidation peaks.MEA-based AST measurements were also performed to evaluate the stability of these commercial catalysts and compare the results with those obtained from the RDE protocol. This study examines the correlations between RDE- and MEA-derived stability rankings and discusses the limitations of RDE-based ASTs when applied to practical fuel cell conditions.The validated RDE protocol was further applied to self-synthesized RuPt/C and Ru_corePt_shell materials, providing a reliable and cost-effective approach for assessing Ru leaching during early-stage catalyst development. These findings highlight the potential of the RDE-based AST for advancing PEM fuel cell anode catalysts tailored for reformate hydrogen applications.

Evaluation of health problems in the Para athlete cohort is well-established. Nonetheless, analyses of the association between mental health and injury, illness or variability of training and competition are spare. Therefore, the purpose of this prospective observational study was to assess this potential relationship in a cohort of Para athletes. Continuous health monitoring of German Paralympic athletes using the Oslo Sports Trauma Centre (OSTRC) questionnaire and Patient Health Questionnaire-4 (PHQ-4) on a weekly basis. Additionally, primary sporting activity, training exposure, and subjective training intensity per week were recorded. PHQ-4 scores in relation to substantial health problems were analyzed [mean (M) and 95% confidence interval (95%CI)]. A regression tree analysis was used to analyze the relationship between the independent variables age, sex, impairment type, and sport, as well as the stress level, mood, PHQ-4 sum score, subjective training intensity, training exposure, main weekly activeness, type of health problem, and if it was a substantial health problem, 4 consecutive weeks and dependent variable, the PHQ-4 sum score in the fifth week. Over an observation period of 124 weeks, 122 Para athletes reported a total of 438 health problems and a mean PHQ-4 score of M = 1.3 (95%CI: 1.3-1.4). Highest mean score was observed during illnesses (M = 2.6; 95%CI: 2.2-3). The regression tree identified the leading PHQ-4 score and current mood or stress level as the primary predictors, while all other independent variables did not contribute to the model's prediction. The findings suggest a potential impact of physical health concerns on mental health, though these, and variations in training or competition were not identified as predictors for the mental health status in a Para athlete cohort. In addition, mean PHQ-4 scores remained below clinical cut-off values, suggesting the need for individualized support to ensure adequate management.

Spontaneous intracranial hypotension (SIH) due to lateral dural tears with spinal longitudinal extradural fluid collections (SLECs) can cause disabling orthostatic headaches. While epidural patching is commonly used as first-line treatment, outcomes specific to lateral dural tears have not been well-characterized. We aimed to evaluate clinical and radiologic outcomes following CT-guided patching for lateral dural tears and assess whether anatomic or procedural factors-including the presence of a herniated arachnoid pouch, patch volume, material, or approach-influence treatment success. This was a retrospective multicenter cohort study of patients with lateral dural tears treated with CT-guided epidural patching between December 2013 and March 2025. Demographics, leak characteristics, patching details, and clinical and imaging outcomes were collected. The presence of herniated arachnoid pouches on spine MRI and pre-/posttreatment Bern scores were recorded. Associations among clinical resolution, SLEC resolution, and procedural variables were analyzed using univariate methods. Fifty-six patients (mean age, 38.7 [SD, 11.7] years; 80% female) were included. Mean pretreatment Bern score was 6.6 (SD, 2.3); no patients had superficial siderosis. Clinical resolution occurred in 20/56 (35.7%), and SLEC resolution occurred in 10/40 (25%) on postpatch spine MRI. A herniated arachnoid pouch was present in 69.7% and was associated with lower SLEC resolution (30% versus 80%, P =.003). Patch type, volume, transforaminal approach, and needle placement into the herniated pouch were not associated with outcomes. Postpatch Bern scores were lower among those with clinical resolution (0.9 [SD, 1.1] versus 2.6 [SD, 2.5]; P = .046). Of 11 patients with complete clinical improvement who had postpatch spine MRI, 5 (45.5%) had persistent SLECs. CT-guided patching led to complete symptom resolution in roughly one-third of patients with lateral dural tears. Herniated arachnoid pouch predicted lower SLEC resolution, while procedural variables were not predictive of outcome. A subset of patients improved clinically despite persistent extradural fluid, emphasizing the need for long-term monitoring.

Professional identity (PI) has been linked to job satisfaction and retention, with research suggesting that fostering a strong PI during nursing education can help mitigate burnout and reduce turnover. However, few studies have explored how various learning experiences contribute to PI development. The purpose of this study was to describe the connections between educational experiences and PI. An open-ended prompt was disseminated to prelicensure nursing students. Participants described an experience that connected them to their PI. Thematic analysis was used to analyze responses and identify key themes. Four main themes emerged as influential in PI development: relationships, confidence, autonomy, and hinge moments. Positive relationships with patients, preceptors, and colleagues were identified as critical in strengthening PI. Clinical and classroom experiences that boosted confidence and autonomy were also essential. Hinge moments, such as meaningful patient interactions or significant clinical events, were pivotal in shaping students' PI. Findings identified key factors that shape PI, emphasizing the need for hands-on learning experiences such as simulations and early clinical exposure.

Pendant longtemps, trop longtemps probablement, Roger Fajnzylberg a renoncé à ouvrir la « boîte à chaussures, entourée d’une cordelette qui a jauni au fil des ans » (p. 11) qui contenait les cahiers rédigés par son père Alter. Ce n’est qu’en 2001, après le décès de son père et de sa mère, qu’il s’est décidé à percer le secret de la boîte. Puis il a encore hésité à rendre public le témoignage de son père. Près de 80 ans après leur rédaction, ces cahiers sont enfin mis au jour. Ils renferment ...