Mit dem LASSO auf Wellenjagd - KI für die Mischungsanalyse

Der Einsatz von Zweikomponenten-Epoxidharz-Systemen zur Imprägnierung von Preforms in isothermen RTM-Prozessen (engl. Resin Transfer Moulding) erlaubt eine kostengünstige und nachhaltige Bauteilfertigung in der Luftfahrt. Die Inline-Mischungsanalyse in solchen Systemen ist ein elementarer Baustein für eine qualitätsgesicherte Fertigung. Es kommen spezielle Sensoren zum Einsatz, die eine indirekte Messung von Mischungsverhältnissen ermöglichen. Der mathematische Zusammenhang zwischen Messung und Mischungsverhältnis ist jedoch komplex und entzieht sich einer genauen Beschreibung durch klassische Modelle. Daher nutzt das DLR in Zusammenarbeit mit Industriepartnern datenbasierte Ansätze, um die Inline-Mischungsanalyse für Zweikomponentensysteme realisierbar zu machen

DEVELOPMENT OF THE DIRECT ROVING PLACEMENT TECHNOLOGY (DRP)

The Direct Roving Placement (DRP) technology is in development at the Institute of Composite Structures and Adaptive Systems of the German Aerospace Center (DLR). A fully functional robotic unit that is able to produce dry glass or carbon fiber preforms has been set up at the Center for Lightweight Production Technology (ZLP) in Stade. All relevant process and material parameters that have an influence on the mechanical properties of parts being built with the DRP technology, are investigated. The main advantages of this new fiber placement technology are low material costs and high productivity. The core of the technology, the end-effector, is able to process raw carbon fibers as well as glass fiber rovings. The biggest difference compared to other placement technologies is the integrated online binder application system. The binder system is used to keep the fiber rovings fixed in position, after they have been applied onto a three-dimensional tooling surface. In addition, the online application of a binder provides multiple options of individually tuning the mechanical properties of the preform or the final part

Spatial patterns of microsclerotia from Verticillium dahliae Kleb. in soils of Bavarian maple stands

In den vergangenen Jahren wurden durch die Bayerische Landesanstalt für Wald und Forstwirtschaft vermehrt Stammnekrosen an Ahornbäumen, die durch den bodenbürtigen Erreger Verticillium dahliae Kleb. verursacht werden, diagnostiziert. In dem hier vorgestellten Projekt wurden in fünf Ahornbeständen entlang eines jeweils 100 m langen Transektes Bodenproben auf Mikrosklerotien hin und Stammschäden an dem Bestand untersucht. Ziel war es zu prüfen, ob der Erreger durch infiziertes Pflanzgut in die Bestände gebracht worden ist. Die Ergebnisse konnten diesen Zusammenhang nicht bestätigen. Die Verteilung der Mikrosklerotien im Boden wies keinen erkennbaren Zusammenhang mit den geschädigten Ahornbäumen auf. Die Ergebnisse deuten viel mehr darauf hin, dass sich der Erreger unabhängig von gesunden und kranken Ahornen in den Beständen etabliert hat. Jahrringzählungen anhand von geschädigten Bäumen deuten darauf hin, dass der Schaden unmittelbar nach der extremen Trockenheit im Jahr 2003 eingetreten ist. Somit wird ein Zusammenhang zwischen extremen Witterungsereignissen und der Erkrankung vermutet.    During the last years, the Bavarian State Institute of Forestry received increasing numbers of announcements that dealt with necrosis on stems of maple trees caused by the soilborne fungus Verticillium dahliae Kleb. In this study, five forest areas were investigated along transects up to 100 m by soil sampling and mapping of diseased trees to find out if the pathogen had been introduced by infested maple seedlings. Our results yielded no evidence for this assumption. The spatial distribution of microsclerotia concentrations in the soil did not correlate with spatial patterns of diseased trees. This indicates that Verticillium was established on the sample plots independently from healthy or infested maple trees. Counting of year rings of infested maple trees revealed that the trees had developed their necrosis immediately after the drought in the year 2003. Hence, a connection between these extreme climate conditions and disease incidence cannot be excluded.   &nbsp

Social Protest Between Deprivation and Populism. A Study of the Demonstrations Against the „Hartz IV“ Unemployment Act

In autumn 2004 massive protests against reforms of the unemployment benefit — known as the „Hartz IV reform“ — rose overall in Germany. Shortly afterwards, right-wing-extremist parties were substantially successful in the following federal elections. Not only politicians, but also theories of deprivation and disintegration indicate a causal relationship in presuming that unemployment leads to an affinity with right-wing political parties. We analyzed the relation of unemployment and political affinity (political orientation, negative evaluation of the established parties and voting intention) with respect to right-wing and left-wing populism. 1150 individuals, participating in demonstrations in East- and West-Germany, were interviewed with standardized questionnaires. As hypothesized, unemployment influenced political affinity. However, it turned out that the actual state of occupation hardly had an effect. More in detail, subjective fears of unemployment by those, who are in work, and subjective fears to be directly or indirectly concerned by Hartz IV by those, who are not employed, count for political affinity with specific patterns for East and West Germans. While only some of the differences between East- and West-German participants can be explained by differences in objective and subjective deprivation, the effect of deprivation is mainly explained by the agreement with right- and especially left-wing populism. On the whole, only a small proportion of variance of political affinity can be explained by East-West origin, state of occupation and populism

Wild bee and floral diversity co-vary in response to the direct and indirect impacts of land use

Loss of habitat area and diversity poses a threat to communities of wild pollinators and flowering plants in agricultural landscapes. Pollinators, such as wild bees, and insect‐pollinated plants are two groups of organisms that closely interact. Nevertheless, it is still not clear how species richness and functional diversity, in terms of pollination‐relevant traits, of these two groups influence each other and how they respond to land use change. In the present study, we used data from 24 agricultural landscapes in seven European countries to investigate the effect of landscape composition and habitat richness on species richness and functional diversity of wild bees and insect‐pollinated plants. We characterized the relationships between the diversity of bees and flowering plants and identified indirect effects of landscape on bees and plants mediated by these relationships. We found that increasing cover of arable land negatively affected flowering plant species richness, while increasing habitat richness positively affected the species richness and functional diversity of bees. In contrast, the functional diversity of insect‐pollinated plants (when corrected for species richness) was unaffected by landscape composition, and habitat richness showed little relation to bee functional diversity. We additionally found that bee species richness positively affected plant species richness and that bee functional diversity was positively affected by both species richness and functional diversity of plants. The relationships between flowering plant and bee diversity were modulated by indirect effects of landscape characteristics on the biotic communities. In conclusion, our findings demonstrate that landscape properties affect plant and bee communities in both direct and indirect ways. The interconnection between the diversities of wild bees and insect‐pollinated plants increases the risk for parallel declines, extinctions, and functional depletion. Our study highlights the necessity of considering the interplay between interacting species groups when assessing the response of entire communities to land use changes

Mental Health and Health-Related Quality of Life in German Adolescents after the Third Wave of the COVID-19 Pandemic

Evaluations after the first and second waves of the COVID-19 pandemic in Germany showed an increase in mental health problems and a reduction in health-related quality of life (HRQoL). The aim of the study was to assess those aspects after the third wave of COVID-19 in adolescents who decided to receive a vaccination. In students aged 12–17 years recruited from schools in one German region, mental health (by the strengths and difficulties questionnaire, SDQ) and HRQoL (by KIDSCREEN-10) were assessed by both a self- and parental report. Data from 1412 adolescents (mean age 14.3 years, SD = 1.64) and 908 parents were collected. The mean self reported HRQoL was T = 53.7 (SD = 11.2), significantly higher in boys than in girls and higher in younger (12–14 years) than in older (15–17 years) adolescents. In total, 18.7% of adolescents reported clinically relevant psychological symptoms, especially peer problems (23.5%), emotional problems (17.4%), and hyperactivity (17.1%). Comparing the present data to evaluations after the first and second waves of COVID-19, adolescents rated a higher HRQoL and reported less mental health problems after the third wave. After 1.5 years of living with the pandemic, adolescents have adapted to the changes in everyday life. Further, the relaxation of restrictions, better school organization, and the prospect of the vaccination may have increased optimism, wellbeing, and contentment, leading to declining but still alarming rates of psychological symptoms

Sensorintegriertes Multifunktionswerkzeug zur Prozessoptimierung (SiMP) im Verbundvorhaben "iFeZ" - Intelligentes Formwerkzeug der Zukunft

Im Rahmen des Vorhabens "iFeZ - Intelligentes Formwerkzeug der Zukunft" widmete sich das DLR vor dem Hintergrund einer erfahrungsbasierten Fertigung von FVK-Luftfahrtbauteilen mit einem hohen Anteil manueller und damit variierender Prozessschritte der Umsetzung eines sensorintegrierten und multifunktionalen Formwerkzeuges innerhalb einer intelligent vernetzten Produktionsumgebung zur aktiven Prozessgestaltung mit dem Ziel einer nachhaltigen Komponentenfertigung. Die Aktivitäten im Teilvorhaben "Sensorintegriertes Multifunktionswerkzeug zur Prozessoptimierung" (SIMP) konzentrieren sich auf Untersuchungen zur Sensierung der Fertigungsteilprozesse Tränkung und Aushärtung von Faserverbundbauteilen und umfasste die Definition geometrischer und laminatspezifischer Bauteilqualitätskriterien sowie die Sensorauswahl und -entwicklung zur Erfassung der relevanter Größen. Neben dem Nachweis zur Funktionsfähigkeit der Einzeltechnologien erfolgte die Implementierung in ein vorhandenes Formwerkzeug mittels Digital Mock Up. Weiterhin wurde die Integration in die Gesamtanlageninfrastruktur vorgenommen sowie eine vollständig vernetzte Systemumgebung auf Basis bereitgestellter Services aufgebaut. Die Analyse und Validierung erfolgte in Fertigungsversuchen am Funktionsmuster: Spant. Neben dem Potential der Live-Visualisierung der erfassten Daten konnte deren Kopplung mit der Prozesssimulation zur Bauteil-Zustandsbeschreibung auf Basis von Sensorstützstellen und Simulationsmodellen gezeigt werden. Die Ergebnisse zeigen gleichermaßen die Möglichkeit der digitalen Transformation für vorhandene Produktionssysteme als auch das Potential der Daten für mehr Produktionseffizienz bei Faserverbunden. Within the framework of the project "iFeZ - Intelligent mold of the future", the DLR, against the background of an experience-based production of FRP aerospace components with a high proportion of manual and thus varying process steps, devoted itself to the implementation of a sensor-integrated and multifunctional mold within an intelligently networked production environment for active process design with the aim of sustainable component production. The activities in the sub-project "Sensor-integrated multifunctional mold for process optimisation" (SIMP) focus on investigations into the sensing of the sub-processes impregnation and curing of fibre composite components and include the definition of geometric and laminate-specific component quality criteria as well as sensor selection and development to record the relevant variables. In addition to the verification of the functionality of the individual technologies, the implementation in an existing mold was carried out by means of digital mock-up (DMU). Furthermore, the integration into the overall plant infrastructure was carried out and a fully networked system environment was set up on the basis of services. The analysis and validation was realised in experiments on the functional model: Z-frame. In addition to the potential of live visualization of the collected data, its coupling with process simulation for state description based on sensors and simulation models could be shown. The results demonstrate both the possibility of digital transformation for existing production systems and the potential of the data for more production efficiency in fiber composites

Tissue Localization and Extracellular Matrix Degradation by PI, PII and PIII Snake Venom Metalloproteinases: Clues on the Mechanisms of Venom-Induced Hemorrhage

20 páginas, 4 figuras, 3 tablas y 7 tablas en material suplementario.Snake venom hemorrhagic metalloproteinases (SVMPs) of the PI, PII and PIII classes were compared in terms of tissue localization and their ability to hydrolyze basement membrane components in vivo, as well as by a proteomics analysis of exudates collected in tissue injected with these enzymes. Immunohistochemical analyses of co-localization of these SVMPs with type IV collagen revealed that PII and PIII enzymes co-localized with type IV collagen in capillaries, arterioles and post-capillary venules to a higher extent than PI SVMP, which showed a more widespread distribution in the tissue. The patterns of hydrolysis by these three SVMPs of laminin, type VI collagen and nidogen in vivo greatly differ, whereas the three enzymes showed a similar pattern of degradation of type IV collagen, supporting the concept that hydrolysis of this component is critical for the destabilization of microvessel structure leading to hemorrhage. Proteomic analysis of wound exudate revealed similarities and differences between the action of the three SVMPs. Higher extent of proteolysis was observed for the PI enzyme regarding several extracellular matrix components and fibrinogen, whereas exudates from mice injected with PII and PIII SVMPs had higher amounts of some intracellular proteins. Our results provide novel clues for understanding the mechanisms by which SVMPs induce damage to the microvasculature and generate hemorrhage.This work was performed in partial fulfillment of the requirements for the PhD degree for Cristina Herrera at Universidad de Costa Rica.Peer reviewe

Problematic Internet Use among Adolescents 18 Months after the Onset of the COVID-19 Pandemic

Studies in recent years and especially since the beginning of the COVID-19 pandemic have shown a significant increase in the problematic use of computer games and social media. Adolescents having difficulties in regulating their unpleasant emotions are especially prone to Problematic Internet Use (PIU), which is why emotion dysregulation has been considered a risk factor for PIU. The aim of the present study was to assess problematic internet use (PIU) in adolescents after the third wave (nearly 1.5 years after the onset in Europe) of the COVID-19 pandemic. In the German region of Siegen-Wittgenstein, all students 12 years and older from secondary-level schools, vocational schools and universities were offered a prioritized vaccination in August 2021 with an approved vaccine against COVID-19. In this context, the participants filled out the Short Compulsive Internet Use Scale (SCIUS) and two additional items to capture a possible change in digital media usage time and regulation of negative affect due to the COVID-19 pandemic. A multiple regression analysis was performed to identify predictors of PIU. The original sample consisted of 1477 participants, and after excluding invalid cases the final sample size amounted to 1268 adolescents aged 12–17 (x = 14.37 years, SD = 1.64). The average prevalence of PIU was 43.69%. Gender, age, digital media usage time and the intensity of negative emotions during the COVID-19 pandemic were all found to be significant predictors of PIU: female gender, increasing age, longer digital media usage time and higher intensity of negative emotions during the COVID-19 pandemic were associated with higher SCIUS total scores. This study found a very high prevalence of PIU among 12- to 17-year-olds for the period after the third wave of the COVID-19 pandemic, which has increased significantly compared to pre-pandemic prevalence rates. PIU is emerging as a serious problem among young people in the pandemic. Besides gender and age, pandemic-associated time of digital media use and emotion regulation have an impact on PIU, which provides starting points for preventive interventions

Do drivers of biodiversity change differ in importance across marine and terrestrial systems — Or is it just different research communities' perspectives?

Cross-system studies on the response of different ecosystems to global change will support our understanding of ecological changes. Synoptic views on the planet's two main realms, the marine and terrestrial, however, are rare, owing to the development of rather disparate research communities.We combined questionnaires and a literature review to investigate howthe importance of anthropogenic drivers of biodiversity change differs amongmarine and terrestrial systems and whether differences perceived by marine vs. terrestrial researchers are reflected by the scientific literature. This included asking marine and terrestrial researchers to rate the relevance of different drivers of global change for either marine or terrestrial biodiversity. Land use and the associated loss of natural habitatswere rated as most important in the terrestrial realm,while the exploitation of the sea by fishing was rated as most important in the marine realm. The relevance of chemicals, climate change and the increasing atmospheric concentration of CO2 were rated differently for marine and terrestrial biodiversity respectively. Yet, our literature review provided less evidence for such differences leading to the conclusion that while the history of the use of land and sea differs, impacts of global change are likely to become increasingly similar