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Nicotine dependence is associated with an increased risk of developing chronic, non-communicable inflammatory disease: a large-scale retrospective cohort study
Get PDFIntroduction Chronic, non-communicable inflammatory diseases (CIDs) affect a large portion of the population, imposing a significant morbidity, encompassing a substantial mortality. Thus, they are a major medical burden with a high unmet need. CIDs develop over the span of several years, and the risk of developing CIDs has been linked to genetic and environmental factors. Thus, modification of environmental factors is a promising approach for the prevention of CIDs. Among modifiable environmental factors that have been linked to the CID risk is nicotine dependence. However, for only few CIDs, compelling evidence suggests that nicotine dependence increases (e.g., rheumatoid arthritis and asthma) or decreases (e.g., pemphigus) the CID risk. For most CIDs, there are inconsistent, scant, or no reports on the risk of CID associated with nicotine dependence. Methods To address this gap, we leveraged TriNetX, analyzing data from over 120 million electronic health records (EHRs). Using propensity score matching (PSM) to control for age, sex, ethnicity, and other CID risk factors, we contrasted the risk of developing any or any of the 38 CIDs in 881,192 EHRs from individuals with nicotine dependence to PSM-matched unexposed counterparts. Results The analytical pipeline was validated by demonstrating an increased risk of individuals exposed to nicotine dependence for subsequent diagnosis of myocardial infarction, malignant neoplasm of the lung, and chronic obstructive pulmonary disease. Overall, 16.8% of individuals with nicotine dependence developed CIDs, compared to 9.6% of individuals not exposed to nicotine dependence (hazard ratio 2.12, confidence interval 2.10-2.14, p < 0.0001). Investigating single CIDs, nicotine dependence imposed increased risks for 23 of the 38 investigated diseases, i.e., dermatomyositis, granulomatosis with polyangiitis, pyoderma gangrenosum, and immune thrombocytopenic purpura
Modeling the Dynamics of Long-Term Variability of Hydro-Climatic Processes and Associated Extreme Events in the Rift Valley Lakes Basin, Ethiopia
Get PDFEarth's hydrological cycles have been modified during the past four decades by anthropogenic, hydro-climatic, and geological forces. Long-term variability must be comprehended for sustainable water resources management, climate adaptation, and disaster risk reduction. The Rift Valley Lakes Basin of Ethiopia is under large-scale land use change due to population pressure, urbanization, and agriculture, along with uncertain climate dynamics. This study examines hydro-climate variables, land use dynamics, and their effects on hydrology using machine learning, hydrologic modeling (SWAT+), change point analysis, and bathymetry surveys. Land use dynamics during the period between 1989 and 2019 experienced a 27.5% increase in agriculture while natural vegetation, wetlands, and water bodies decreased. The climate analysis reflected a non-significant reduction in rainfall but significant increase in temperature. These alterations, driven mostly by population growth and agricultural practice, altered water availability. Hydrological simulation indicated reduced precipitation, evapotranspiration, and infiltration, and increased surface runoff from 2000 to 2005 compared to 1989–2000. Land use change was a more dominant factor than climate fluctuation. Southern basin lakes expanded, and northern lakes shrunk. The surface area of Lake Chamo increased by 30 km², and Lake Abijata lost 68% of its surface area due to water abstraction and reduced inflows. The findings indicate rising human-induced stresses on the hydrological system of the basin, and the need for sustainable water management. The study provides useful information on long-term hydro-climatic dynamics, with implications for similar data-scarce regions
Soziale Transformationen im 5. Jahrtausend im Žitava-Tal, Südwest-Slowakei
Get PDFThe dissertation, titled "Social Transformations during the 5th Millennium in the Žitava Valley, SW Slovakia," examines sociocultural changes in the Žitava Valley between the 6th and 5th millennia BCE. It focuses on the transition from the Late Linear Pottery Culture (LBK) to the Lengyel Culture, analyzing how these transformations fit within broader European Neolithic developments. A key aspect of the study is ceramic analysis, emphasizing technological choices rather than typological evolution. The research highlights the significance of organic tempering in pottery, linking it to economic and agricultural strategies. It also suggests that continuity in ceramic traditions reflects cultural persistence despite population shifts. The dissertation incorporates material from 13 sites, including Vráble-Fárske, Bajč, and Čierne Kľačany, selected for their well-documented stratigraphy. Methodologies include traditional ceramic analysis, thin-section petrography, and scanning electron microscopy (SEM) to identify organic inclusions and technological choices. Findings indicate that technological decisions became more standardized over time, suggesting increasing social interaction despite population dispersal. The study also examines mass graves, mobility patterns, and gender roles, proposing that ceramic production was gendered, with household ceramics linked to female transmission of knowledge. The dissertation contributes to debates on Neolithic population movements, social organization, and economic adaptation, offering a regional case study within the broader transformation of early farming societies in Europe
On the importance of Mongolian cyclones to East Asian dust storms
No full textIn East Asia, dust storms typically occur in spring with adverse impacts on socio-economic activities, loss of life, and climate. Mongolian cyclones that form downstream of the Altai-Sayan Mountain have been known for some time as drivers of spring dust storms in East Asia. The passage of Mongolian cyclones primarily induces dust-emitting winds in the Gobi Desert, leading to dust emissions and favoring the subsequent transport of dust aerosols across Northern China. Herein, the relative contributions of Mongolian cyclones to dust emissions in the Gobi Desert and subsequent dust storm activity in Northern China are assessed from a climatological perspective for the first time in this dissertation. Furthermore, this study provides the first evidence that dust activity in the Taklamakan Desert, which is located in the west of the Gobi Desert, is also supported by Mongolian cyclones. This assessment aims to illustrate the importance of Mongolian cyclones in generating spring dust storms across East Asia
TEM analysis of nanoparticles for solar energy conversion prepared by gas cluster aggregation source
Get PDFIn the scope of this cumulative thesis, different nanoparticle materials that can be applied for different pathways of solar energy conversion were characterized by transmission electron microscopy. The nanoparticles were mostly fabricated by gas aggregation cluster source systems. This fabrication method offers the potential of high purity and flexibility. Next to its advantages, the particle formation process is highly complex and can be influenced by a multitude of factors. Therefore, the particle synthesis in gas aggregation cluster source systems is not well understood and its potential is only partially exploited. The combination of results from transmission electron microscopy with complementary analytical methods revealed connections between deposition parameters and resulting particle properties. The presented studies provide insights into the relevance of the discharge voltage as deposition parameter, provide possible particle formation mechanisms of new material combinations in the gas cluster aggregation source and extend the fabrication technique by combination with secondary depositions
Schnelle Verfahren für BEM-Probleme mit Hilfe von H-Matrix-Techniken: Effizientes Aufstellen von Randintegraloperatoren kombiniert mit shared-memory-Parallelisierung der H-Arithmetik für schnelle Vorkonditionierer
Get PDFDie Randelementmethode (BEM) wird zur Berechnung von linearen, homogenen, partiellen Differentialgleichungen verwendet, um Lösungen auch im Außenraum der Geometrie effizient auswerten zu können. Hierbei sind die auftretenden Systemmatrizen üblicherweise vollbesetzt. Für große Probleme wird dieses Verfahren daher aufgrund des hohen Rechen- und Speicheraufwands schnell unattraktiv. Zur Lösung beider Probleme führen wir die H-Matrizen ein, die an geeigneten Stellen Berechnungen durch Approximationen ersetzen und dadurch die Effizienz massiv steigern. Der erste Teil dieser Arbeit beschäftigt sich damit, wie die Randintegraloperatoren mithilfe moderner CPUs und deren Technologien, wie Multithreading und Vektorisierung, effizient im Kontext der H-Matrizen aufgestellt werden können. Als Lösungsverfahren nutzen wir das GMRES bzw. des CG-Verfahrens für positiv definite, symmetrische Matrizen. Es zeigt sich, dass bei wachsender Problemgröße diese Verfahren immer mehr Iterationsschritte benötigen und somit in ihrer Anwendung immer teurer werden. Vorkonditionierer helfen dabei, diesen Nachteil deutlich zu reduzieren. Die H-Matrizen bieten ein sehr mächtiges Werkzeug, um Vorkonditionierer mithilfe von approximativen Dreieckszerlegungen bzw. approximativen Inversen zu konstruieren. Leider sind diese Verfahren schwierig zu parallelisieren. Daher wird ein großer Teil dieser Arbeit der Frage gewidmet, wie eine sinnvolle Verteilung der Arbeitslast auf mehrere Rechenkerne erreicht werden kann. Wir stellen ein Konzept vor, dass auf Tasks basiert und während einer rein symbolischen Ausführung der oben genannten Operationen Verknüpfungen zwischen diesen Teilaufgaben herstellt, sodass sie später gleichmäßig auf die verfügbare Hardware verteilt werden können
Workplace Physical Activity Interventions: Longitudinal, Dynamic, and Meta-Analytic Insights
Get PDFThis dissertation investigates the effectiveness of workplace physical activity interventions (WPAIs) in enhancing employees’ health and functioning. Physical inactivity is recognized as a silent pandemic, contributing to numerous health risks such as musculoskeletal complaints (MSC) and increased absenteeism. As the workplace increasingly involves sedentary tasks, WPAIs—which integrate regular bouts of physical activity in organizational contexts—have emerged as a promising approach for improving employee well-being. Notably, mind-body interventions (combining physical and mindfulness-based components) may outperform body-only interventions focusing solely on physical exertion. Three empirical studies form the core of this work. Study 1, a longitudinal randomized controlled trial (RCT) with 459 office workers, compares an office-yoga and a walking intervention. Both effectively reduced the prevalence and intensity of MSC, although walking proved slightly superior for alleviating complaint intensity. Study 2 reanalyzes these data to examine how early success (i.e., initial velocity and acceleration in MSC reduction) predicts overall effectiveness, highlighting the importance of fostering positive intervention experiences at the outset. Study 3, a meta-analysis of 80 RCTs, found that WPAIs reduce mental and physical health complaints and bolster organizational outcomes (e.g., job satisfaction, productivity), with mind-body approaches showing consistently higher effectiveness than body-only interventions. Group-based WPAIs also demonstrate better adherence in studies targeting health complaints. Overall, this dissertation underscores the value of holistic, well-structured WPAIs—emphasizing initial momentum, adherence, and the added benefits of mindfulness-based and group-based formats—for advancing employee health and performance in the modern workplace
Untersuchungen zum Einfluss tumorassoziierter Fibroblasten sowie Perineuralscheiden auf Proliferation und Migration beim cholangiozellulären Karzinom
No full textBeim cholangiozellulären Karzinom (CCC) handelt es sich um einen seltenen, malignen Tumor der Gallenwege mit steigender Inzidenz. Die chirurgische Resektion des Tumors stellt bisher die einzige kurative Therapieoption dar, die jedoch aufgrund des meist hohen Tumorstadiums bei Diagnosestellung nicht mehr möglich ist, weshalb oftmals lediglich eine palliative Systemtherapie mit schlechten Überlebensraten indiziert ist. Auf der Suche nach neuen zielgerichteten Therapieansätzen ist das Tumorstroma aufgrund der protumorösen Eigenschaften in der letzten Zeit immer stärker in den Fokus der Forschung gerückt. Da auch das CCC einen hohen Anteil an desmoplastischen Stroma aufweist, war das Ziel dieser Arbeit, den Einfluss parakriner Interaktionen durch tumorassoziierte Fibroblasten (CAFs) und einer noch kaum analysierten Komponente des Tumorstromas, den Schwann´schen Zellen, auf die Progression beim CCC näher zu ergründen
3D-print som læringskontekst i matematikundervisningen: Brugen af digitale teknologier som læringskontekster til at fremme fagspecifikke færdigheder samt karriereorientering og -forberedelse på første og andet sekundærtrin
Get PDFIn Anbetracht der fortschreitenden Digitalisierung der Arbeitswelt sowie des gegenwärtigen und künftigen Fachkräftemangels unterliegen die Anforderungsprofile an (zukünftige) Arbeitnehmende einem kontinuierlichen Wandel. Um zukünftigen Arbeitnehmenden den Übergang in die Arbeitswelt zu erleichtern, kann eine frühzeitige Orientierung und Vorbereitung auf die digitale Arbeitswelt von Nutzen sein. Dementsprechend wird in den allgemeinbildenden Schulen neben der Förderung fachlicher, emotionaler und sozialer Kompetenzen zusätzlich ein Schwerpunkt auf die Möglichkeiten einer frühzeitigen Berufsorientierung und -vorbereitung gelegt. Die curricularen Ziele der allgemeinbildenden Schulen sind von essentieller Bedeutung, so dass sich daraus eine Diskrepanz zwischen den curricularen Inhalten der einzelnen Unterrichtsfächer und den beim Übergang in die Arbeitswelt erwarteten Kompetenzen in Bezug auf digitale Technologien ergibt. Die vorliegende kumulative Dissertation begegnet dieser Diskrepanz am Beispiel der Verknüpfung des regulären Mathematikunterrichts mit der 3D-Druck-Technologie unter Zuhilfenahme des Ansatzes des Educational Design Research. Für die Entwicklung von authentischen und einsetzbaren Unterrichtskonzepten und -materialien wurden zwei Rahmenbedingungsstudien sowie anschließend drei formative und zwei summative Evaluationszyklen durchgeführt. Um einen breiten Einsatz der entwickelten und evaluierten Unterrichtskonzepte zu gewährleisten, wurden nach der letzten summativen Evaluierung Kurz-Fortbildungen für Lehrkräfte durchgeführt, die hinsichtlich ihrer kurzfristigen Wirkung evaluiert wurden. Das Forschungsprojekt kann eine Vorgehensvorlage für eine Weiterentwicklung des Lernkontextansatzes in verschiedenen Bereichen darstellen.In view of the ongoing digitalization of the world of work and the current and future shortage of skilled workers, the requirements profiles for (future) employees are subject to continuous change. In order to make the transition into the world of work easier for future employees, early orientation and preparation for the digital world of work can be beneficial. Accordingly, in addition to promoting technical, emotional and social skills, general education schools also focus on opportunities for early career guidance and preparation. The curricular objectives of general education schools are of essential importance, resulting in a discrepancy between the curricular content of the individual subjects and the skills expected in the transition to the world of work with regard to digital technologies. This cumulative dissertation addresses this discrepancy using the example of linking regular mathematics lessons with 3D printing technology with the help of the Educational Design Research approach. For the development of authentic and applicable teaching concepts and materials, two framework studies and subsequently three formative and two summative evaluation cycles were carried out. In order to ensure a broad application of the developed and evaluated teaching concepts, short training courses for teachers were carried out after the last summative evaluation, which were evaluated with regard to their short-term effect. The research project can serve as a template for the further development of the learning context approach in various areas.I lyset af den igangværende digitalisering af arbejdslivet og den nuværende og fremtidige mangel på kvalificeret arbejdskraft er kravprofilerne for (fremtidige) medarbejdere under konstant forandring. For at gøre overgangen til arbejdslivet lettere for fremtidige medarbejdere kan tidlig orientering og forberedelse til den digitale arbejdsverden være gavnlig. Ud over at fremme tekniske, følelsesmæssige og sociale færdigheder fokuserer almendannende skoler derfor også på muligheder for tidlig karrierevejledning og -forberedelse. De almendannende skolers faglige mål er af afgørende betydning, hvilket resulterer i en uoverensstemmelse mellem det faglige indhold i de enkelte fag og de kompetencer, der forventes i overgangen til arbejdslivet med hensyn til digitale teknologier. Denne kumulative afhandling behandler denne uoverensstemmelse ved hjælp af eksemplet med at forbinde almindelige matematiktimer med 3D-printteknologi ved hjælp af Educational Design Research-tilgangen. For at udvikle autentiske og anvendelige undervisningskoncepter og -materialer blev der gennemført to rammestudier og efterfølgende tre formative og to summative evalueringscyklusser. For at sikre, at de udviklede og evaluerede undervisningskoncepter anvendes bredt, blev der efter den sidste summative evaluering arrangeret korte kurser for lærere, som blev evalueret med hensyn til deres virkning på kort sigt. Forskningsprojektet kan fungere som en skabelon for den videre udvikling af læringskonteksttilgangen på forskellige områder
Host-Symbiont Interactions in the Mammalian Lung
Get PDFThe human body hosts diverse microbial communities colonizing every surface. The commensal microbes that populate the gut, skin, and lung are now recognized for their role in maintaining organ homeostasis. Despite the lung being previously considered sterile in healthy individuals, it is now understood that they harbor a microbial community that plays an essential role in lung development and immunity. In this thesis, we aimed to contribute to a more comprehensive understanding of the role played by host genetics in the shaping of lung microbiota composition. In Chapter 1, I employed the in vitro cell culture system to further examine a proposed link between the Lactobacillus and the mouse Mk2 and Il10 genes. By analyzing candidate host genes and performing RNA-seq, potential probiotic Lactobacillus species for use in humans and mice were identified. The candidate species appear to interact with the host, thereby mitigating the inflammatory response via the MK2 and JNK1 pathways. Both Lactobacillus rhamnosus and Lactobacillus murinus are presented as excellent candidates for further investigation. In Chapter 2, an in vivo Mk2 knockout mouse model was employed for the characterization of the lung and gut microbiota. The gut microbiota was found to exhibit taxa with differential abundance according to Mk2 genotype. A comparison of the microbiota from the two body sites revealed the presence of shared taxa, suggesting a gut-lung axis. In Chapter 3, I present evidence that the selection of an extraction kit can introduce biases in the interpretation of microbial composition in such low biomass environments. The findings highlight the limitations of current methodologies and the inability to clearly identify contaminant taxa. Contaminants that are specific to the kit in question were identified