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Podiumsdiskussion: Auf der Suche nach Gerechtigkeit : über die Aufklärung geschlechtspezifischer Gewalt in Bosnien und Herzegowina und der Ukraine : sexualisierte Gewalt als Kriegswaffe
No full textTowards a global understanding of tree mortality
No full textRates of tree mortality are increasing globally, with implications for forests and climate. Yet, how and why these trends vary globally remain unknown. Developing a comprehensive assessment of global tree mortality will require systematically integrating data from ground-based long-term forest monitoring with large-scale remote sensing. We surveyed the metadata from 466 865 forest monitoring plots across 89 countries and five continents using questionnaires and discuss the potential to use these to estimate tree mortality trends globally. Our survey shows that the area monitored has increased steadily since 1960, but we also identify many regions with limited ground-based information on tree mortality. The integration of existing ground-based forest inventories with remote sensing and modelling can potentially fill those gaps, but this requires development of technical solutions and agreements that enable seamless flows of information from the field to global assessments of tree mortality. A truly global monitoring effort should promote fair and equitable collaborations, transferring funding to and empowering scientists from less wealthy regions. Increasing interest in forests as a natural climate solution, the advancement of new technologies and world-wide connectivity means that now a global monitoring system of tree mortality is not just urgently needed but also possible
Advanced imaging of type 2 spinal CSF leaks with ultrahigh-resolution cone-beam CT myelography
No full textDental and oral health assessments in the German National Cohort (NAKO)
No full textBackgroundDespite considerable improvements in oral health in recent decades, caries and periodontitis are still widespread, ranking among the most prevalent diseases worldwide and requiring future research. The German National Cohort (NAKO Gesundheitsstudie, NAKO) is a large-scaled, multidisciplinary, nationwide, multi-centre, population-based, prospective cohort study with oral examinations that aims to provide a resource to study risk factors for major diseases. The aim of the present article is to provide the methodological background, to report on the data quality, and to present initial results of the oral examinations.MethodsDuring baseline examinations (2014–2019), a total of 205,184 persons aged 19–74 years has been examined in 18 study centres, including, among others, a dental interview, stimulated saliva sampling, and recording of the numbers of present teeth and prostheses (standard Level 1 program). As part of the Level 2 program that was offered to 20% randomly selected participants, each study centre selected one of three modules, one of them being the Level 2 oral examination. This extended program was carried out in a subgroup of 20,828 participants, including collection of detailed information on the dental and prosthetic status as well as on periodontal, cariological and functional aspects. To ensure reliability and reproducibility, study nurses were trained and calibrated by dental experts. In addition, a reliability study was conducted among 794 Level 1 and 359 Level 2 participants, reporting intra class correlation and kappa coefficients.ResultsIntra class correlation and kappa coefficients for observer agreement and reliability were consistently above 0.7, indicating good to excellent reliability of all dental measurements. For example, intra class correlation was 0.937 for the number of present teeth (Level 1), 0.740 for mean probing depth (PD) and 0.797 for active mouth opening. An initial inspection of the data showed that the median number of present teeth was 27, of which on average 6.9 teeth were healthy and caries-free. Average mean PD was 1.92 mm. An orthodontic treatment was reported by 35.5% of participants.DiscussionOverall, the dental study protocol was feasible and successfully integrated into the NAKO’s overall assessment program. However, rigorous support of the study centres by dental professionals was required to ensure high quality data. In summary, high-quality data collection within the NAKO pave the way for future investigation of potential risk factors for oral diseases and links between oral and systemic diseases and conditions
Preoperative non-invasive mapping for targeted concomitant surgical ablation of non-paroxysmal atrial fibrillation (PreMap study)
No full textBackground/Objectives: The present study introduces our targeted approach for concomitant surgical ablation (CSA) using non-invasive phase mapping (NIPM) and describes its effectiveness regarding freedom from atrial fibrillation (AF). Methods: This retrospective study included cardiac surgical patients undergoing preoperative NIPM for CSA guidance. The primary outcome was freedom from AF six months after surgery. Key secondary outcomes were freedom from AF at hospital discharge and three months, frequency of biatrial ablation, feasibility and safety, the rate of CSA, complications, and levels of biomarkers. The control group consisted of patients undergoing CSA without NIPM. Results: Forty-four patients (Control: n = 31/NIPM: n = 13) were included. The NIPM group was younger (64 vs. 71 years [p = 0.044]), had a lower EuroSCORE II (2.6 vs. 3.4 [p = 0.041]), and a smaller left atrial size (46 mm vs. 54 mm [p = 0.025]). Surgery duration was longer in the NIPM group (285 vs. 230 min [p = 0.037]) with similar aortic cross-clamp times. Preoperative NIPM resulted in an effective frequency of CSA of 93%. CSA was more extensive in the NIPM group, with biatrial ablation performed in 54% vs. 26% of patients (p = 0.09). Conclusions: Routine preoperative NIPM in patients with non-paroxysmal atrial fibrillation might aid in increasing the number of patients receiving concomitant surgical ablation and developing a personalized CSA approach for every patient
Drone remote sensing for forest health monitoring
No full textForest health is critical for maintaining the multitude of ecosystem ser-vices that forests provide, including carbon sequestration, biodiversityconservation, water regulation, and soil conservation. The ability offorests to perform these functions is directly linked to their health con-dition, making forest health monitoring essential for sustainable forestmanagement and climate change mitigation. Traditional methods ofmonitoring forest health involve time-consuming and labor-intensive,sample-based ground observations. While valuable, these methodsare limited in scope and scalability and include highly subjectiveevaluations.This research addresses these limitations by exploring UncrewedAerial Vehicle (UAV)-based forest health monitoring as a viable alter-native. This dissertation is based on three articles that were preparedas part of a multi-year remote sensing research project at the BavarianState Institute of Forestry (LWF). In the course of the project, 235Level-1-Monitoring plots of the International Co-operative Programon Assessment and Monitoring of Air Pollution Effects on Forests (ICPForests) were surveyed with UAVs in parallel to the terrestrial inven-tories in the years 2020– 2022. In this way multispectral aerial imageswere collected and merged into a large long-term and cross-temporaltime-series dataset.The first article scopes the theoretical foundation of the work. Witha review that provides researchers and practitioners with an overviewof previous work related to forest health monitoring and that intro-duces the latest technology. To achieve this, 99 papers were evaluated,offering a broad perspective on advancements and methodologies inthe field of UAV-based forest health monitoring. The review identi-fied research gaps and trends to guide future research efforts anddirections.Based on this gathered knowledge, the subsequent articles built onthese insights to develop and test innovative UAV-based monitoringtechniques. Consequently, the research presented in the second articledescribes the development of an open-source data pipeline that aimsto link UAV data with field data of forest health assessments in astandardized and streamlined process. This contributed to the semi-automatic generation of training data for the training of deep learningmodels. In a large-scale flight campaign, multispectral UAV data from235 ICP Forests inventory plots in Bavaria were recorded annually overthe years 2020- 2022. The field data from the same inventory points ofthe related years were used as a reference to validate the aerial data.With the developed pipeline, more than 17,000 training samples of thefive major tree species occurring in Germany including their healthstatus, two genus classes as well as dead trees could be generated.In this way, we were able to classify 14 different classes with anaverage macro F1-score of 0.61 using the EfficientNet ConvolutionalNeural Network (CNN) architecture. The highest class-specific F1score besides the class of dead trees (0.97) was achieved by the classof healthy Picea abies (0.80).Originating from the same database, species-specific gradient-boosting models were trained. The results, presented in the thirdarticle, indicate that multispectral images captured by a drone closelymatch field data and allow for effective detection of physiologicalstress in trees. Surprisingly, in addition to the red, red-edge, and near-infrared bands, the blue band also proved to be a critical indicator oftree stress, with its effectiveness varying depending on factors suchas tree species, classification detail, and atmospheric conditions. Fur-thermore, the values averaged over three years per sample tree, alongwith the 5th and 25th percentiles of the data distribution, were foundto be particularly important because they provide a more compre-hensive understanding of tree stress patterns over time. The use ofpercentiles helps to capture the variability and extremes in the dataset,highlighting early signs of stress that may not be visible in averagevalues alone. The species-specific models were then trained based onthe spectral indices, resulting in good classification accuracies (MacroF1-Score between 0.492 and 0.769).In essence, this thesis examines the integration of traditional moni-toring methods with UAV-based remote sensing to enhance the effi-ciency and effectiveness of forest health assessments. Through casestudies and empirical data, the research demonstrates how dronescan identify stress responses in trees and provide insights into forestdynamics.The findings suggest that drone technology offers a significant ad-vancement in forest health monitoring, supporting the developmentof targeted conservation strategies and sustainable forest managementpractices. Compared to traditional methods, UAVs enable more ob-jective assessments through high-resolution, wall-to-wall mapping,providing full coverage of large areas at lower costs and with greaterefficiency. This approach has the potential to ensure that forests con-tinue to thrive, provide essential ecosystem services, and contribute tolong-term economic sustainability in the face of increasing environ-mental challenges
Mikrophänomenologische Analyse von Anfällen mit autoskopischen Phänomenen bei Menschen mit Epilepsie
No full textEinige Autoren sprechen der Epilepsie die Rolle der häufigsten Ätiologie für autoskopische Phänomene (AP) zu. Die vorliegende Arbeit hat das Ziel, die Struktur der subjektiven Erfahrung der Anfälle mit AP bei Menschen mit Epilepsie zu untersuchen und ein tieferes Verständnis dieser zu generieren. Es soll die Frage geklärt werden, welche gemeinsamen abstrahierten diachronen Strukturen und welche gemeinsamen abstrahierten synchronen Strukturen die subjektiven Erfahrungen der Anfälle mit AP bei den untersuchten Menschen mit Epilepsie haben.Es wurden Erfahrungen von Anfällen mit AP von sechs Menschen mit Epilepsie untersucht. Zwei der Patient:innen berichteten von ihren Anfällen mit AP in mikrophänomenologischen Interviews, vier Patient:innen in Arzt-Patienten-Gesprächen. Die Transkripte der Beschreibungen von den Anfällen mit AP wurden nach der mikrophänomenologischen Methode analysiert.Für die analysierten Erfahrungen deckt diese Studie eine klare gemeinsame abstrahierte diachrone Struktur der Anfälle mit AP auf. Diese beinhaltet die Entfaltung von fünf Phasen. Die Analyse der synchronen Struktur der AP ergab, dass die Erfahrungen der AP phänomenologisch gemäß ihrer drei Haupttypen weiter differenziert werden können. Für die verschiedenen untersuchten Haupttypen der AP wurden sechs deskriptive Kategorien gebildet, welche für die jeweiligen Haupttypen der AP eine gemeinsame abstrahierte synchrone Struktur der Erfahrung beschreiben.Die Ergebnisse dieser Arbeit lassen vermuten, dass das AP bei Menschen mit Epilepsie innerhalb von Anfällen an verschiedenen Stellen der diachronen Struktur der Anfälle auftreten kann. Die Struktur der Anfälle verläuft trotz des zusätzlichen Elements der Autoskopie vermutlich analog zu Anfällen ohne AP. Des Weiteren lässt sich vermuten, dass Menschen mit Epilepsie und autoskopischen Halluzinationen bezüglich ihrer AP mehr Angst und Leidensdruck erleben als Menschen mit Epilepsie und Out-of-body experience. Weiter wird die Hypothese aufgestellt, dass eine unterschätzte Häufigkeit und ein unterschätzter Leidensdruck bezüglich der AP bei Menschen mit Epilepsie bestehen.Es lässt sich schlussfolgern, dass die gezielte Anamnese bezüglich AP bei Menschen mit Epilepsie einen Mehrwert bieten könnte und eine gezielte Aufklärung von Menschen mit Epilepsie und AP ggf. die Angst bei Menschen mit Epilepsie und autoskopischer Halluzination verringern könnte. Zu der abschließenden Klärung dieser wichtigen Schlussfolgerungen und Hypothesen ist weitere Forschung notwendig. Zukünftige Forschung sollte sich auf eine größere Fallzahl beziehen
Dissecting the mechanism underlying T cell receptor-mediated intercellular transfer of peptide-Major Histocompatibility complexes
No full textCell surface molecules have been observed to pass from one cell to another as part of their interaction. This phenomenon, known as trogocytosis, has been observed in many cell types, particularly in the immune system. One receptor that is fundamental to the body`s defence against many pathogens is the expressed polymorphic T cell receptor (TCR), which interacts with major histocompatibility complex molecules loaded with antigenic peptides (pMHC). While TCR-mediated trogocytosis of MHC complexes has been described in a number of publica- tions, the underlying mechanisms as well as the fate of the acquired pMHC molecules remain unclear. The aim of this thesis is to gain a better understanding of TCR-mediated trogocytosis of pMHC. The transfer of pMHC from donor to recipient cells was quantified by flow cytometry using both fluorescent proteins covalently linked to the intracellular domain of pMHC and fluorescent an- tibodies. We demonstrated that TCR-mediated trogocytosis of pMHC occurs across a species barrier, as murine 58ab OT-1 T cells were able to acquire corresponding murine pMHC from Chinese hamster ovary cells. This limited trogocytosis to one type of receptor-ligand interaction and improved the reliability of our experimental system. In the first part, we investigated the role of pMHC-TCR affinity on the efficacy of trogocytosis. By generating a library of cell lines expressing pMHC with different LCMV gp33 peptides, we were able to show a positive correlation between TCR-pMHC affinity and the efficiency of tro- gocytosis. In the second part, we investigated whether TCR-mediated trogocytosis depends on this TCR signalling function or occurs independently. TCR-mediated pMHC trogocytosis was unaffected by blocking TCR signalling with the Src kinase inhibitors PP2 or A77. Furthermore, efficient trogocytosis could be achieved by cell lines expressing variants of CD3e, namely C80G and K76T, which have been reported to block TCR signalling. Taken together, our data suggest that TCR-mediated trogocytosis of pMHCs is independent of TCR signalling. Lastly, we analysed the fate determinants of trogocytosed pMHC. The generation of pMHC as single chain trimers with non-cleavable linkers increased the surface expression of acquired pMHC compared to pMHC constructs with cleavable linkers. Trogocytosis of pMHC is known to involve internalization of TCR-pMHC into intracellular vesicles, exposing this association to the environment within the vesicles. As we have shown that non-cleavable linkers increase the susceptibility of pMHC to acidification and proteases, we hypothesise, that this facilitates dis- sociation of TCR and pMHC, leading to recycling of the pMHC
Development and maintenance of consensus recommendations on pediatric outpatient antibiotic therapy in Germany: a framework for rational use
No full textIn pediatric outpatient care, overuse and misuse of antibiotics is linked to a high risk of adverse events and increased antibiotic resistance. In 2019, building upon the work of the Antibiotic Therapy in Bielefeld (AnTiB) project (founded in 2016), a collaboration among the AnTiB, the German Society for Pediatric Infectious Diseases (DGPI), and the Professional Association of Outpatient Pediatricians and Adolescent Physicians (BVKJ) was established to develop consensus recommendations for antibiotic therapy in pediatric outpatient settings in Germany. This working group became the Antibiotic Stewardship in Outpatient Pediatrics (ABSaP). ABSaP institutes recommendations for antibiotic use in outpatient pediatric settings in Germany and updates them regularly. The ABSaP guidelines recommend restrictive, targeted, evidence-based prescription practices for antibiotics used to treat common infections among pediatric outpatients. This expert-driven, pragmatic, best-practice guidance is designed to be a living document. ABSaP’s most recent update was published in March 2024. The recommendations aim to guide and standardize rational antibiotics use by emphasizing the importance of avoiding unnecessary prescriptions, while also promoting the application of narrow-spectrum antibiotics, short-duration therapy, and watchful waiting, when treating mild, self-limiting infections in children without significant risk factors.Conclusions: ABSaP’s guidelines may provide a model for others, as well as offer a basis for discussing practical, effective antibiotic stewardship (ABS) measures in pediatric primary care. An international, expert consensus on ABS for pediatric outpatients could help promote a culture of responsible antibiotic use, improve prescribing safety, and contribute to broader ABS efforts
Comparability of fatigue strength and life estimation of a CF-PEKK composite under low and ultrasonic frequencies using time-temperature-based approaches
No full textPredicting very high cycle fatigue (VHCF) life in composites is challenging due to the lengthy testing times required by traditional methods. Ensuring compatibility between VHCF and high cycle fatigue (HCF) data presents an additional challenge. This investigation examines CF-PEKK fatigue behavior under low and ultrasonic cyclic frequencies using a thermographic approach and the fracture fatigue entropy (FFE) concept. Constant-amplitude fatigue (CAF) and increasing-amplitude fatigue (IAF) tests were conducted, with self-heating behavior analyzed for different loading conditions. Heat dissipation rates from IAF experiments and fatigue data from three CAF experiments at 40 Hz and three at 20 kHz were used to calculate FFE values. Results showed that the self-heating response of CF-PEKK specimens helps achieve comparable fatigue data across frequencies, with consistent FFE ranges identified between HCF and VHCF regimes. This consistency highlights that FFE can provide reliable fatigue life estimation for composites