Technische Universität Dresden: Qucosa
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Catalog of Dynamical System Models with Semantic Metadata
No full textThis contribution presents the concept and implementation of a catalog (i.e., a structured collection) of dynamical system models, relevant to control theory. The key features of the catalog are: (a) a combination of human-readable model documentation with executable code; (b) semantic metadata for each model plus a web platform to provide SPARQL search interface; and (c) model data and supporting software based on open source repositories and open for extension and improvement
Holocene landscape evolution, palaeoclimate and human impact in the Fotsch Valley, Stubai Alps, Austria: Interrogating biomarkers, stable isotopes, macrofossils and palynological indicators from a subalpine mire archive
No full textPeatlands are receiving increasing attention in palaeoenvironmental research and represent very useful terrestrial archives for reconstructing vegetation, climate and human history. Previous palaeoenvironmental studies in the Fotsch Valley, Stubai Alps, Austria, focused on geoarchaeological investigations on the Ullafelsen representing a very important prehistorical encampment site used by Mesolithic hunter-gatherers (10.9–9.5 cal. kyr BP). In order to contribute to a better understanding of the landscape evolution of the Fotsch Valley, we here studied the close-by subalpine ‘Potsdamer Hütte Mire’ by applying radiocarbon dating as well as elemental, biomarker, compound-specific stable isotope, palynological and macrofossil analyses on bulk peat samples. The calculated age-depth model using R Bacon indicates the beginning of peat formation during the Early Holocene and shows a strongly reduced peat accumulation rate (PAR) from 170 to 121 cm depth (8.5–2.1 cal. kyr BP) and/or a striking hiatus. Results of leaf wax-derived n-alkane biomarkers as well as macrofossils and palynological indicators reflect the local presence of coniferous trees and the synchronous expansion of deciduous trees during the Early Holocene. The above-mentioned strongly reduced PAR and/or hiatus coincides with the Neolithic, the Bronze and the Iron Age, and goes hand in hand with strong changes in vegetation and an increase of micro-charcoal and black carbon. Despite age uncertainties, these changes can be explained with strongly increasing human and livestock activities in form of deforestation, domestic fires and the beginning of Alpine pastoralism. The latter is confirmed by the finding of pasture and cultural indicator pollen (Cerealia-type, Rumex, Plantago lanceolata, Poaceae) occurring since the Middle to Late Bronze Age. The oxygen isotope composition of sugar biomarkers (δ¹⁸O/sugars) likely reflects the dry versus humid climatic variability associated with the Holocene climatic optimum during the Mesolithic, the Roman Age, the Late Antique Little Ice Age, the Middle Ages and the Little Ice Age
Transferrin receptor 2 deficiency promotes macrophage polarization and inflammatory arthritis
No full textObjective: Rheumatoid arthritis is an inflammatory joint disease in which synovial iron deposition has been described. Transferrin receptor 2 (Tfr2) represents a critical regulator of systemic iron levels. Loss of Tfr2 function in humans and mice results in iron overload. As iron contributes to inflammatory processes, we investigated whether Tfr2-deletion affects the pathogenesis of inflammatory arthritis in an iron-dependent manner. -
Methods: Using a global and conditional genetic disruption of Tfr2, we assessed the relevance of Tfr2 in K/BxN serum-transfer arthritis (STA) and macrophage polarization. - Results: Male Tfr2⁻⸍⁻ mice subjected to STA developed pronounced joint swelling, and bone erosion as compared to Tfr2⁺⸍⁺ littermate-controls (P < 0.01). Furthermore, an increase of neutrophils and macrophages/monocytes was observed in the inflammatory infiltrate within the paws of Tfr2⁻⸍⁻ mice. To elucidate whether Tfr2 in myeloid cells has a direct role in the pathogenesis of arthritis or whether the effects were mediated via the systemic iron overload, we induced STA in Tfr2ᶠˡ⸍ᶠˡ-LysMCre + mice, which showed normal iron-loading. Cre + female mice displayed increased disease development compared to Cre-controls. As macrophages regulate iron availability and innate immunity, we hypothesized that Tfr2-deficiency would polarize macrophages toward a pro-inflammatory state (M1) that contributes to arthritis progression. In response to IFN-γ stimulation, Tfr2⁻⸍⁻ macrophages showed increased expression of M1-like cytokines, IFN-γ-target genes, nitric-oxide production, and prolonged STAT1 activation compared to Tfr2⁺⸍⁺ macrophages (P < 0.01), while pre-treatment with ruxolitinib abolished Tfr2-driven M1-like polarization. -
Conclusion: Taken together, these findings suggest a protective role of Tfr2 in macrophages on the progression of arthritis via suppression of M1-like polarization
Associations of an Easy-to-Understand Patient Letter on the Health Literacy of Patients after Discharge from Hospital: Results of a Randomized Controlled Intervention Study
No full textBackground: 54% of the German population has limited health literacy, which is associated with poorer health outcomes and higher utilization of the healthcare system. - Aim of the study: The aim of this pilot study was to examine the effects of an easy-to-understand patient letter on patients’ health literacy after discharge from a Clinic for Internal Medicine and to analyze patients’ need for written, easy-to-understand information. - Method: In a randomized controlled trial (2016–2018), the effects of the patient letter on health literacy were examined by means of the HLS-EU-Q47 questionnaire. The intervention group (IG, n=242) received an easy-to-understand patient letter 3 days after discharge, the control group (KG, n=175) received only the usual medical discharge letter. - Results: 60% of post-discharge patients were found to have limited health literacy. The study could not show any effect of patient letters on overall health literacy. The analysis of single items of health literacy showed positive effects of these letters on patients’ comprehension of medical advice as well as their understanding and implementation of medication instructions (Cohens d≥0.20). Furthermore, patients expressed their wish for information after discharge from hospital (99%) and rated the patient letter as informative, understandable and helpful. - Conclusions: Patients wish to receive and are empowered by an easy-to-understand letter after discharge from hospital with medical information and medical instructions that they can implement at home.Hintergrund: 54% der deutschen Bevölkerung verfügt über eine eingeschränkte Gesundheitskompetenz. Eingeschränkte Gesundheitskompetenz ist assoziiert mit schlechteren Gesundheitsoutcomes und höherer Inanspruchnahme des Gesundheitssystems. - Ziel der Arbeit: In der Pilotstudie wurden Effekte eines Patientenbriefs auf die Gesundheitskompetenz nachstationärer Patienten einer Inneren Klink mittels HLS-EU-Q47 untersucht. Zudem wurde der Bedarf an schriftlichen, leicht verständlichen Informationen analysiert. - Methodik: In einer randomisiert kontrollierten Studie (2016–2018) wurden die Effekte des Patientenbriefs auf die Gesundheitskompetenz nachstationärer Patienten mittels eines Fragebogens geprüft. Die Interventionsgruppe (IG, n = 242) erhielt 3 Tage nach Entlassung einen Patientenbrief, die Kontrollgruppe (KG, n = 175) nur den üblichen ärztlichen Entlassbrief. - Ergebnisse: 60% der Patienten wiesen eine eingeschränkte Gesundheitskompetenz auf. Die Studie konnte keinen Einfluss der Patientenbriefe auf das Gesamtkonzept Gesundheitskompetenz nachweisen. Die Analyse von Einzelitems der Gesundheitskompetenz zeigte, dass das Verständnis von ärztlichen Anweisungen sowie das Verstehen und Anwenden von Informationen und Einnahmehinweisen zu Medikamenten stieg (Cohens d ≥ 0,20). Zudem berichteten Patienten einen hohen Bedarf an Informationen nach Krankenhausaufenthalt (99%) und bewerteten den Patientenbrief als informativ, verständlich und hilfreich. - Schlussfolgerungen: Ein leicht verständlicher Patientenbrief befähigt Patienten zum besseren Verstehen und Anwenden medizinischer Informationen und Anweisungen. Patientenseitig besteht ein hoher Bedarf an verständlichen Informationen nach Krankenhausaufenthalt
Inertial migration of non-spherical particles in straight microfluidic channels
No full textThe paper reports on simulations of particulate flows in square ducts with oblate and prolate particles at a bulk Reynolds number of 100 and dilute particle concentration. Inertial migration leads to focusing of particles in specific regions of the cross section. It is observed that these positions are different for the non-spherical particles compared to those obtained with spherical ones. Prolate particles exhibit Jeffery-type orbits, while oblate particles rotate around their axis of symmetry. As a result, the rotation-induced migration of prolates is much slower than for spheres and oblates. An analysis of the surrounding flow is used to show differences in the velocity field. In a second set of simulations, the particle concentration was increased by a factor of 4 with the same domain size, so that neighboring particles influence each other. The duration until focusing is achieved is substantially increased. The focusing position moves slightly to the wall, and further effects are generated. Steady particle oscillations in position are seen for spheres, and the formation of particle trains is observed in all cases. The interaction of prolate particles is particularly complex and addressed in substantial detail
The Diagnostic Interview for Sexual Dysfunctions in Women for DSM-5 and ICD-11: Development and initial validation using a vignette-based approach
No full textObjectives
The aim of this study was to evaluate the psychometric properties of the newly developed Diagnostic Interview for Sexual Dysfunctions in Women (DISEX-F), which covers diagnostic criteria of DSM-5 and ICD-11.
Methods
Thirty-two actresses portrayed 32 cases of female sexual dysfunctions (= standardized patients). To calculate inter-rater reliability, each standardized patient was interviewed independently by two trained diagnosticians using the DISEX-F. Interviews were videotaped, and each videotape was evaluated by two other independent diagnosticians. Sensitivity and specificity were calculated by comparing the assigned diagnoses to the target diagnoses pre-determined in the case vignettes. As a side criterion, the acceptance of the DISEX-F among diagnosticians was assessed.
Results
Specificity was found to be generally clinically satisfying (DSM-5: 0.90–0.99; ICD-11: 0.95–0.99), while sensitivity (DSM-5: 0.40–0.92; ICD-11: 0.71–0.96) and inter-rater reliability (DSM-5: Cohen's kappa = 0.44–1; ICD-11: Cohen's kappa = 0.75–0.94) greatly varied between classification systems and disorders. Imprecise acting and false differential diagnostic decisions were identified as major sources of mismatch. The acceptance of the DISEX-F was high.
Conclusion
Results encourage usage of the DISEX-F for ICD-11 diagnoses. Mixed results were found for DSM-5 diagnoses, which can partly be explained by shortcomings in DSM-5 criteria
Active BiVO4 Swimmers Propelled by Depletion Gradients Caused by Photodeposition
No full textArtificial active matter often self-propels by creating gradients of one or more species or quantities. For chemical swimmers, most frequently either O2 or H+ that are created in certain catalytic reactions are causing the interfacial flows which drive the self-propulsion. While the palette of reactions is extending constantly, especially toward more bio-compatible fuels, the depletion of species is often overlooked. Here, the photodeposition of metal species on BiVO4 micro swimmers is considered. During the photodeposition reaction, metal ions are removed from the solution creating a depleted region around the particle. The ability of this depletion to drive active motion of artificial micro swimmers, as well as the influences of different metal ions and counter ions on the motion are investigated and cross compared
Pair Interaction between Two Catalytically Active Colloids
No full textDue to the intrinsically complex non-equilibrium behavior of the constituents of active matter systems, a comprehensive understanding of their collective properties is a challenge that requires systematic bottom–up characterization of the individual components and their interactions. For self-propelled particles, intrinsic complexity stems from the fact that the polar nature of the colloids necessitates that the interactions depend on positions and orientations of the particles, leading to a 2d − 1 dimensional configuration space for each particle, in d dimensions. Moreover, the interactions between such non-equilibrium colloids are generically non-reciprocal, which makes the characterization even more complex. Therefore, derivation of generic rules that enable us to predict the outcomes of individual encounters as well as the ensuing collective behavior will be an important step forward. While significant advances have been made on the theoretical front, such systematic experimental characterizations using simple artificial systems with measurable parameters are scarce. Here, two different contrasting types of colloidal microswimmers are studied, which move in opposite directions and show distinctly different interactions. To facilitate the extraction of parameters, an experimental platform is introduced in which these parameters are confined on a 1D track. Furthermore, a theoretical model for interparticle interactions near a substrate is developed, including both phoretic and hydrodynamic effects, which reproduces their behavior. For subsequent validation, the degrees of freedom are increased to 2D motion and resulting trajectories are predicted, finding remarkable agreement. These results may prove useful in characterizing the overall alignment behavior of interacting self-propelling active swimmer and may find direct applications in guiding the design of active-matter systems involving phoretic and hydrodynamic interactions
Can wells in the vadose zone be backfushed to regain infltration capacity?: Concept and laboratory test
No full textVadose zone wells (VZW), or drywells, allow for high infiltration rates combined with small area demand. Nevertheless, they are rarely used for managed aquifer recharge, since turbid water leads to gradual clogging and a reduction in infiltration capacity. Established redevelopment measures require backflushing, which is commonly considered impossible for VZWs, making them “non regenerable”. In this study, the possibility of backflushing a VZW is discussed. Key to the underlying approach is isolating the lower (clogged) section of a well and saturating its surrounding with water by infiltration via the upper (unclogged) screen. Subsequently, underpressure sucks water from the surrounding soil into the isolated section. The approach was tested with and without a gravel pack, on laboratory scale, showing a successful reversal of flow direction in both cases. The degree of redevelopment was quantified by measuring the drainage time of the well, which increased from initially 45 s without gravel pack and 40 s with gravel pack to 9,500 and 11,000 s, respectively, after clogging. After backflushing, the well with gravel pack showed a median drainage time of 95 s, which remained stable over ten cycles of clogging and backflushing. In contrast, drainage time of the well without gravel pack increased continuously to >170 s, even after vibrator application. In conclusion, it can be stated that the backflush of a VZW with the presented approach is possible and has an effect on the well’s infiltration capacity, though it seems more effective for wells with gravel pack
Investigation of mesalazine as an antifibrotic drug following myocardial infarction in male mice
No full textObjectives:
Myocardial infarction (MI) initiates a complex reparative response during which damaged cardiac muscle is replaced by connective tissue. While the initial repair is essential for survival, excessive fibrosis post-MI is a primary contributor to progressive cardiac dysfunction, and ultimately heart failure. Currently, there are no approved drugs for the prevention or the reversal of cardiac fibrosis. Therefore, we tested the therapeutic potential of repurposed mesalazine as a post-MI therapy, as distinct antifibrotic effects have recently been demonstrated.
Methods:
At 8 weeks of age, MI was induced in male C57BL/6J mice by LAD ligation. Mesalazine was administered orally at a dose of 100 μg/g body weight in drinking water. Fluid intake, weight development, and cardiac function were monitored for 28 days post intervention. Fibrosis parameters were assessed histologically and via qPCR.
Results:
Compared to controls, mesalazine treatment offered no survival benefit. However, no adverse effects on heart and kidney function and weight development were observed, either. While total cardiac fibrosis remained largely unaffected by mesalazine treatment, we found a distinct reduction of perivascular fibrosis alongside reduced cardiac collagen expression.
Conclusions:
Our findings warrant further studies on mesalazine as a potential add-on therapy post-MI, as perivascular fibrosis development was successfully prevented