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Hydrogel Microneedle Array‐Based Transdermal Dressing System for Multiplexed Assessment and Intelligent Therapy of Chronic Wounds
Full text linkTopical chronic wound dressings offer personalized management but have limited efficacy in sensing and delivering therapeutics due to their reliance on the wound surface. Herein, a theranostic hydrogel-forming microneedles (HFMNs) dressing system is developed that penetrates the epidermis to continuously sample dermal wound interstitial fluid (ISF), providing high-fidelity diagnostics and active therapy. The dressing is fabricated from a polyvinyl alcohol/chitosan hydrogel incorporating MXene for intrinsic antibacterial and pro-healing properties. Central to the platform's design is a laser-scribed phase separation process that converts a poly(3,4-ethylenedioxythiophene): polystyrene sulfate/graphene oxide coating into highly conductive (384 S/m) and water-stable electrodes directly on the HFMNs. This enables a multiplexed, replaceable array for continuously monitoring seven key wound biomarkers: glucose, uric acid, Na⁺, K⁺, Cl−, pH, and temperature. In vitro studies confirmed the dressing's cytocompatibility and antimicrobial efficacy against E. coli and S. aureus, while in vivo rat models showed accelerated wound closure. Critically, the HFMN system captured the biochemical dynamics of wound infection and healing from wound ISF with significantly greater fidelity and more distinct responses compared to conventional surface sensors sampling exudate. This work validates a robust platform that directly links deep-tissue biomarkers to wound state, paving the way for personalized, proactive chronic wound management
Prehospital and In-Hospital Stroke Care at a Neurovascular Center: A Single-Center Analysis
Full text linkDie Behandlung von Schlaganfallpatienten muss unverzüglich erfolgen, da der Therapieerfolg mit zunehmender Zeit deutlich abnimmt. Moderne Therapien wie die Thrombektomie bei Large-Vessel-Occlusion (LVO) stehen nicht in allen Kliniken zur Verfügung, sodass bei Nachweis eines LVO eine Weiterverlegung erforderlich ist. Gleichzeitig ist eine gezielte Zuweisung wichtig, da viele Patienten schlaganfallähnliche Symptome aufgrund anderer akuter Erkrankungen (Stroke Mimics) zeigen. Im Saarland erfolgt die präklinische Zuweisung anhand des Los Angeles Motor Scores (LAMS). Ziel dieser prospektiven Studie war es zu untersuchen, wie zuverlässig der LAMS Schlaganfallpatienten identifiziert, welche Erkrankungen bei Fehlzuweisungen vorliegen und wie genau LVO detektiert werden können. In dieser prospektiven Studie wurde die präklinische Anwendung des Los Angeles Motor Scores bei 223 Patienten mit Schlaganfallverdacht untersucht. Der Anteil der Stroke Mimics lag bei 26,5 %, wobei epileptische Anfälle und internistische Erkrankungen die häufigsten Differenzialdiagnosen darstellten. Der LAMS zeigte einen hohen negativen prädiktiven Wert zum Ausschluss von Stroke Mimics (bis zu 86,7 %) sowie eine hohe Sensitivität von 86 % zur Identifikation ischämischer Schlaganfälle, insbesondere bei LVO. Die Ergebnisse bestätigen frühere retrospektive und internationale Studien. Im Vergleich zu bislang publizierten Daten war die Stroke-Mimic-Rate am niedrigsten. Insgesamt sprechen die Ergebnisse dafür, dass der LAMS als einfache präklinische Skala zur gezielten Zuweisung von Patienten mit LVO sinnvoll eingesetzt werden kann
The Paper-Toss Test: enhancing bedside recognition of corticobasal syndrome
Full text linkIntroduction: The diagnosis of corticobasal syndrome (CBS) is challenging due to its clinical overlap with other neurodegenerative disorders. Ideomotor apraxia is a core feature of CBS and often presents asymmetrically, but is often under-recognized in the clinical setting. Methods: The “Paper-Toss Test” (PTT) is administered to a video-based case series of four patients with different CBS pathologies (Alzheimer’s disease, progressive supranuclear palsy, and corticobasal degeneration) and involves instructions to throw a paper ball with each hand. A positive test result is indicated by the presence of specific performance deficits of the patient’s affected side such as an absent or delayed release of the paper ball or an interrupted throwing motion. Results: All patients exhibited a positive PTT, independent of the underlying cause of CBS. Discussion: This study proposes the PTT (Paper-Toss Test) as a bedside tool for the detection of unilateral ideomotor apraxia, facilitating the diagnosis of CBS. These deficits correspond to the known impairments in transitive gestures and disturbances of the neuronal apraxia network in CBS patients. These results support further investigation and validation of the PTT in clinical practice
Effect of an Ad Libitum Milk Supply During the First Three Weeks of Life of Dairy Calves on Heart Rate and Heart Rate Variability During Feeding and Rehousing
Full text linkEarly-life feeding strategies are known to affect growth, behavior, and stress physiology in dairy calves. This study examined the effects of different milk feeding regimes on heart rate (HR) and heart rate variability (HRV) during feeding and rehousing as indicators of autonomic activity. Dairy calves were fed either a restrictive milk allowance twice per day (6 L/d; RES; n = 21) or an unlimited amount of milk (ad libitum; ADL; n = 24) during the first three weeks of life[...]To study the cardiac response to the feeding process, six time windows of 5 min each were chosen as follows: resting time at 5.00 a.m., start of personnel activity in the barn, 15 min before feeding, during feeding, 15 min after feeding, and 1 h after feeding. For the evaluation of cardiac response to an unknown stressor such as rehousing, four time windows of 5 min each were selected as follows: resting time at 5.00 a.m., during rehousing, 30 min after rehousing, and 1 h after rehousing. During resting as well as before feeding and rehousing, HR was higher in ADL calves compared with RES calves. During feeding and rehousing, HR reached peak values which were comparable in both groups. HRV variables of the time and frequency domain indicated a shift towards a sympathetic dominance in the balance of the autonomic nervous system during feeding time, particularly in RES calves. Differences between resting and feeding values were demonstrated in RES calves at low-frequency and high-frequency power, whereas no differences were observed in ADL calves which did not react to the feeding process. The cardiac response of calves to rehousing was inconsistent in both groups. An increase in RMSSD and SD1 in ADL calves indicated that the vagal component in the vegetative neurological control was increased in these calves during rehousing. In conclusion, our findings indicate that restrictive milk feeding alters autonomic regulation and may increase physiological stress responses in calves
Comparing Weighted RMSD, Weighted MD, Infit, and Outfit Item Fit Statistics Under Uniform Differential Item Functioning
Full text linkIn educational large-scale assessment studies, uniform differential item functioning (DIF) across countries often challenges the application of a common item response model, such as the two-parameter logistic (2PL) model, to all participating countries. DIF occurs when certain items provide systematic advantages or disadvantages to specific groups, potentially biasing ability estimates and secondary analyses. Identifying misfitting items caused by DIF is therefore essential, and several item fit statistics have been proposed in the literature for this purpose. This article investigates the performance of four commonly used item fit statistics under uniform DIF: the weighted root mean square deviation (RMSD), the weighted mean deviation (MD), the infit, and the outfit statistics. Analytical approximations were derived to relate the uniform DIF effect size to these item fit statistics, and the theoretical findings were confirmed through a comprehensive simulation study. The results indicate that distribution-weighted RMSD and MD statistics are less sensitive to DIF in very easy or very difficult items, whereas difficulty-weighted RMSD and MD exhibit consistent detection performance across all item difficulty levels. However, the sampling variance of the difficulty-weighted statistics is notably higher for items with extreme difficulty. Infit and outfit statistics were largely ineffective in detecting DIF in items of moderate difficulty, with sensitivity limited to very easy or very difficult items. To illustrate the practical application of these statistics, they were computed for the PISA 2006 reading study, and the distribution of the statistics across participating countries was descriptively examined. The findings guide selecting appropriate item fit statistics in large-scale assessments and highlight the strengths and limitations of different approaches under uniform DIF conditions
Involvement of Dentists in Preventing Early Childhood Caries in Germany
Full text linkBackground and Objectives: Early Childhood Caries affect children's quality of life and overall health. This study aimed to assess the involvement of dentists in implementing early preventive measures, including fluoride use, for children aged 6-33 months. Materials and Methods: a multiple-choice questionnaire was distributed in six German states, consisting of two sections: Section I covered participant demographics and Section II included items on dental preventive measures for children. The questionnaire was adapted from a validated German-language source, reviewed by five experts at Kiel University, and tested in a focus group of 30 dentists. Descriptive statistics (mean ± SD or median [IQR]) and Mann-Whitney U tests were used to assess pediatric dentists (PD) and general dentists (GP) involvement in early dental preventive measures. Results: A total of 511 eligible questionnaires were returned (mean age 47 ± 11 year, 63.8% females, 36.7% PD). Both GP and PD routinely recommended a diagnostic dental visit (1 = never, 5 = always), with PD reporting higher frequency (GP: 4 [3-5], PD: 4.5 [4-5]; p = 0.001). Parental training in oral hygiene was performed significantly more often by PD (p < 0.01). PD also recommended tooth brushing with fluoridated toothpaste after the eruption of the first tooth more frequently than GP (GP: 5 [3-5], PD: 5 [4-5]; p = 0.06). Surprisingly, fluoride-free toothpaste was still recommended by a relevant number of respondents in both groups. Conclusions: PDs showed greater involvement in early caries prevention than GP. While most recommended fluoridated toothpaste, many still advised fluoride-free options, highlighting gaps in guideline adherence
Structural and biomechanical adaptations of arthropod parasites to the life on marine mammals
Full text linkArthropods are the most successful animal phylum, representing over 80% of known species. Their evolutionary success is shown in their wide range of forms and ecological strategies, enabling them to inhabit nearly all environments. The marine realm poses major challenges – high salinity, strong currents, low oxygen, high pressure, and temperature shifts – yet arthropods have successfully colonized it, often through parasitism. This study examines the biomechanical and structural adaptations of three phylogenetically distinct marine arthropod parasites: seal lice (Echinophthirius horridus), nasal mites (Halarachne halichoeri, Orthohalarachne attenuata), and whale lice (Isocyamus deltobranchium). All live on diving marine mammals that reach depths of up to 1,500 m, exposing the parasites to extreme conditions that demand specialized adaptations. Using multiple methods, we identify key adaptations in five morpho-functional domains: (i) Morphology – niche-specific body forms and material properties, including flattening, miniaturization, sclerotization, mineralization, and resilin-rich areas. (ii) Attachment – anchoring systems such as snap-hooks, friction pads, proteinaceous adhesives, piercing claws, hooking structures, and controlled adhesive pads. (iii) Locomotion – movement suited to host surfaces and moisture levels. (iv) Respiration – cuticular gas exchange, with some taxa showing sealable tracheae or gill-like features. (v) Drag reduction – streamlined shapes and vortex-generating setae that reduce drag in dynamic flow. These results highlight the ecological plasticity of marine parasitic arthropods and offer a functional basis for understanding host–parasite co-evolution, as well as inspiration for applications in materials science and engineering
Die schulische Facharbeit als Methode wissenschaftspropädeutischen Schreibens in Zeiten von Künstlicher Intelligenz: Eine qualitative Interviewstudie zur Zukunftsfähigkeit der Facharbeit aus Perspektive von Lehrkräften
Full text linkDie schulische Facharbeit gilt als zentrale Methode wissenschaftspropädeutischen Schreibens. Mit dem Aufkommen Künstlicher Intelligenz und der dazugehörigen Frage, wie die Eigenleistung von Lernenden zukünftig bewertet werden soll, steht dieses Prüfungsformat jedoch vor einem tiefgreifenden Wandel. Der Beitrag untersucht, inwiefern Lehrkräfte die Zukunftsfähigkeit der Facharbeit einschätzen. Dazu wird das »DER-Modell« entwickelt, welches drei verschiedene Szenarien bündelt: Eine Abschaffung (Disruption), die Weiterentwicklung unter Einbezug von KI (Evolution) oder eine moderate Anpassung bestehender Strukturen (Reform) der schulischen Facharbeit. Auf Basis von sechs leitfadengestützten Interviews mit Lehrkräften aus Nordrhein-Westfalen werden Einstellungen, Chancen und Herausforderungen qualitativ analysiert. Die Ergebnisse zeigen einerseits ein überwiegend ambivalentes Verhältnis zur Nutzung von KI, andererseits ist vor allem eine eher pessimistischere Grundhaltung erkennbar. Darüber hinaus wird ein Konzept zur zukünftigen Gestaltung der schulischen Facharbeit vorgestellt, welches die Integration von Künstlicher Intelligenz berücksichtigt und zugleich an die geplante Oberstufenreform in Nordrhein-Westfalen anschließt.School research papers are considered a central method of scientific writing. However, with the rise of artificial intelligence (AI) and the associated question of how students’ authentic work can be fairly assessed in the future, this examination format is facing profound change. This article examines the extent to which teachers assess the future viability of research papers. To provide a structured analytical framework, the »DER model« has been developed, which combines three different scenarios: abolition (disruption), further development with the inclusion of AI (evolution), or moderate adaptation of existing structures (reform) of school research papers. Based on six guided interviews with teachers from North Rhine-Westphalia, attitudes, opportunities, and challenges are analysed qualitatively. The study shows that, on the one hand, a predominantly ambivalent attitude toward the use of AI and, on the other hand, a rather pessimistic basic attitude can be observed. In addition, a concept for the future design of school research projects is presented that considers the integration of AI and at the same time ties in with the planned upper secondary school reform in North Rhine-Westphalia
Pacific Coastal Niños: Drivers of Divergent Evolution and the Connection to Westward Propagating El Niño Events
No full textVariability in the tropical Pacific is largely controlled by the El Niño–Southern Oscillation (ENSO). In addition to basin-wide El Niño events, Coastal Niños occur along the South American coast. An extreme example was the 2017 Coastal Niño, which caused severe rainfall and flooding in Peru during February–April. Its exceptional intensity is linked to its early timing, coinciding with the climatologically warmest coastal sea surface temperatures (SSTs). Only during this season can warm anomalies trigger deep convection and heavy rainfall; events peaking later, under cooler SSTs, remain weaker and dominated by stratiform clouds. Another key factor is the state of the central Pacific. In 2017, it remained neutral to weak La Niña, while in 2023, a similar coastal event evolved into a basin-wide El Niño. Model analyses (CESM-LE) indicate that large-scale background conditions, weaker trade winds, and westward-propagating Rossby waves enable the spread of coastal SST anomalies westward, linking regional and basin-wide events. The thesis also introduces a new metric distinguishing westward and eastward propagating SST anomalies. Westward propagation is typical and driven by the climatological surface currents; eastward propagation occurs when these currents reverse and Kelvin waves dominate. Such reversals are linked to the Pacific Decadal Oscillation (PDO): during its positive phase (late 1970s–2000), warmer central Pacific conditions and weaker mean currents favored current reversal, even during moderate events. Overall, the study identifies the 2017 Coastal Niño as a seasonal and climatic outlier, while the 2023 El Niño resembles pre-1980 events influenced by decadal variability and the timing of equatorial wave activity
Functional Polymer Nanocomposites by Gas Aggregation Cluster Source and Initiated Chemical Vapor Deposition
Full text linkFunctional metal-polymer nanocomposites are required for highly tailored surface properties and coatings. However, past approaches like cosputtering, physical evaporation, or plasma polymerization can not retain the functionality of the polymer matrix or produce tailored nanoparticles. A new kind of codeposition of nanocomposite polymer thin films is presented via the combination of a gas aggregation cluster source (GAS) and initiated chemical vapor deposition (iCVD) in a common GAS+iCVD vacuum system. iCVD delivers ultraprecise and defect-free polymer thin films on the nanoscale while a GAS creates nanoparticles that form in the gas phase and can be tuned in size and composition. Using the GAS+iCVD system, nanocomposites of well-defined Ag nanoparticles in a chemically intact PTFE polymer thin film are prepared. The deposited nanocomposite proved applicable in antibacterial applications by decreasing the colony-forming units of Enterococcus faecalis by 38%. Antiviral SARS-CoV-2 Spike-ACE-2 binding inhibition reaches 65% of pure silver nanoparticles. The nanocomposite improves the apoptotic gene expression for liver cancer cells compared to pure thin films. This new kind of codeposition paves the way for the fabrication of functional nanocomposite thin films combining the advantages of the iCVD polymer palette with a large variety of nanoparticles that can be prepared by GAS