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Adolph von Henselt (1814─1889), Klaviervirtuose, Pädagoge und Komponist: Eine pathografische Studie
No full textBestimmung der Grenzzone mittels hyperspektraler Bildgebung bei kolorektalen Resektionen
No full textWährend kolorektalen Resektionen ( Sigma-, Rektumresektionen, Hemikolektomien (links und rechts)) wurden mit einer Hyperspektral-Kamera (HSI) zum Zeitpunkt vor Durchtrennung der Randarkade und 5 Minuten danach jeweils pro Minute Bilder vom zu resezierendem Areal genommen. Die Kamera zeigte schließlich 4 Gewebeparameter (oberflächliche und tiefe Sauerstoffsättigung, Hämoglobin- und Wasserverteilung) in je einem Falschfarbenbild an. Für unsere Studie interessant waren die tiefe und oberflächliche Sauerstoffsättigung. Diese haben wir uns näher angeschaut und mittels der TIVITA Suite AnalyseSoftware analysiert. Wir haben ein 50 mm großes Areal beobachtet: 25 mm distal der Grenzzone und 25 mm zentral der Grenzzone.
Als schlechte Perfusion haben wir den prozentualen Abfall der Durchblutung von unter 80 % definiert.
Es wurde deutlich, dass bereits nach Minute 1 der höchste signifikante Abfall der Perfusion von 19,2 % distal der Grenzzone zu sehen war. Bis Minute 3 stieg der Wert auf 20,8 %%, danach traten jedoch keine weiteren signifikanten Änderungen mehr auf.
Der Chirurg platzierte mit einer Spitze einer Schere die Stelle, die er visuell anhand der Vitalität und der Serosafarbe als Grenzzone definierte. Mit diesen Werten konnten wir beides vergleichen, sodass wir zu dem Entschluss gekommen sind, dass die Hyperspektral-Kamera ein gutes Hilfsmittel ist, um den Chirurgen bei der Entscheidung der Grenzzone zu unterstützen. Seit der Durchführung traten weniger Anastomoseninsuffizienzen postoperativ auf.
Die Anwendung ist ebenfalls sicher und schnell und steril anwendbar.:I Inhaltsverzeichnis I
II Abbildungsverzeichnis II
III Abkürzungsverzeichnis III
1 Einführung 1
1.1 Allgemeine Einführung in die Kolorektalchirurgie 1
1.2 Chirurgisches Vorgehen bei kolorektalen Resektionen 1
1.3 Risiken einer kolorektalen Resektion 3
1.4 Hyperspektrale Bildgebung 4
1.5 Einsatzbereich der Hyperspektral-Kamera 5
1.6 Fluoreszenzangiographie mit Indocyaningrün 6
1.6.1 Vergleich Hypersprektralimaging und Fluoreszenzangiographie mit Indocyaningrün 7
1.7 Studienplanung und Durchführung 7
2 Publikation 9
3 Zusammenfassung der Arbeit 21
IV Literaturverzeichnis IV
V Darstellung des eigenen Beitrags IX
VI Erklärung über die eigenständige Abfassung der Arbeit X
VII Lebenslauf XI
VIII Danksagung XI
Impact of Anterior Malposition and Bone Cement Augmentation on the Fixation Strength of Cephalic Intramedullary Nail Head Elements
No full textBackground and Objectives: Intramedullary nailing of trochanteric fractures can be challenging
and sometimes the clinical situation does not allow perfect implant positioning. The aim of this
study was (1) to compare in human cadaveric femoral heads the biomechanical competence of two
recently launched cephalic implants inserted in either an ideal (centre–centre) or less-ideal anterior
off-centre position, and (2) to investigate the effect of bone cement augmentation on their fixation
strength in the less-ideal position. Materials and Methods: Fourty-two paired human cadaveric femoral
heads were assigned for pairwise implantation using either a TFNA helical blade or a TFNA screw as
head element, implanted in either centre–centre or 7 mm anterior off-centre position. Next, seven
paired specimens implanted in the off-centre position were augmented with bone cement. As a result,
six study groups were created as follows: group 1 with a centre–centre positioned helical blade,
paired with group 2 featuring a centre–centre screw, group 3 with an off-centre positioned helical
blade, paired with group 4 featuring an off-centre screw, and group 5 with an off-centre positioned
augmented helical blade, paired with group 6 featuring an off-centre augmented screw. All specimens
were tested until failure under progressively increasing cyclic loading. Results: Stiffness was not
significantly different among the study groups (p = 0.388). Varus deformation was significantly
higher in group 4 versus group 6 (p = 0.026). Femoral head rotation was significantly higher in
group 4 versus group 3 (p = 0.034), significantly lower in group 2 versus group 4 (p = 0.005), and
significantly higher in group 4 versus group 6 (p = 0.007). Cycles to clinically relevant failure were
14,919 4763 in group 1, 10,824 5396 in group 2, 10,900 3285 in group 3, 1382 2701 in group
4, 25,811 19,107 in group 5 and 17,817 11,924 in group 6. Significantly higher number of cycles
to failure were indicated for group 1 versus group 2 (p = 0.021), group 3 versus group 4 (p = 0.007),
and in group 6 versus group 4 (p = 0.010). Conclusions: From a biomechanical perspective, proper
centre–centre implant positioning in the femoral head is of utmost importance. In cases when this
is not achievable in a clinical setting, a helical blade is more forgiving in the less ideal (anterior)
malposition when compared to a screw, the latter revealing unacceptable low resistance to femoral
head rotation and early failure. Cement augmentation of both off-centre implanted helical blade and
screw head elements increases their resistance against failure; however, this effect might be redundant for helical blades and is highly unpredictable for screws
Individuelle Lernentwicklungsanalyse von Basiskompetenzen in der inklusiven Transition Kita – Schule (ILEA-Basis-T) - Förderbausteine
No full textPhysicochemical Modeling of Electrochemical Impedance in Solid-State Supercapacitors
No full textSolid-state supercapacitors (SSCs) consist of porous carbon electrodes and gel-polymer
electrolytes and are used in novel energy storage applications. The current study aims to simulate
the impedance of SSCs using a clearly defined equivalent circuit (EC) model with the ultimate goal
of improving their performance. To this end, a conventional mathematical and a physicochemical
model were adapted. The impedance was measured by electrochemical impedance spectroscopy
(EIS). An EC consisting of electrical elements was introduced for each modeling approach. The math-
ematical model was purely based on a best-fit method and utilized an EC with intuitive elements. In
contrast, the physicochemical model was motivated by advanced theories and allowed meaningful
associations with properties at the electrode, the electrolyte, and their interface. The physicochemical
model showed a higher approximation ability (relative error of 3.7%) due to the interface impedance
integration in a more complex circuit design. However, this model required more modeling and opti-
mization effort. Moreover, the fitted parameters differed from the analytically calculated ones due to
uncertainties in the SSC’s microscale configuration, which need further investigations. Nevertheless,
the results show that the proposed physicochemical model is promising in simulating EIS data of
SSCs with the additional advantage of utilizing well-reasoned property-based EC elements
The Construction of the “Older Worker”
No full textThe notion of the “older worker” is frequently used in the organizational literature, in organizational practice, and in society, but so far, no research has investigated why people consider someone to be an older worker at a certain age. In the qualitative part of this study, we examined potential reasons for considering workers to be “older” at a certain age. In the quantitative part of this study, we investigated demographic characteristics (i.e., age, sex, education), job characteristics (i.e., job level, typical age in a job), and beliefs (i.e., perceived remaining time at work, motivation to continue working after retirement, positive and negative age stereotypes) as predictors of people’s conceptions of “older worker age”.” Data were provided by 269 employees from various jobs and organizations. The mean age at which participants considered someone to be an “older worker” was approximately 55 years. The most frequently stated reasons for considering workers to be “older” at a certain age were retirement age and age-related decline. Results of a regression analysis showed that participants’ age, sex, and perceived remaining time predicted “older worker age”. These findings provide first insights into the psychological construction of the “older worker”
Distribution patterns of invasive plant species in Germany – Modelling habitat suitability under current and projected climate conditions
No full textInvasive Pflanzenarten, die sich durch hohe Vermehrungsratem und breite Umwelttoleranz auszeichnen, verdrängen oft einheimische Flora, was zu einem Verlust an biologischer Vielfalt und zu wirtschaftlichen Kosten führt. Aufgrund des zunehmenden globalen Handels und des Klimawandels wird erwartet, dass sich die Dynamik biologischer Invasionen in Zukunft intensivieren wird. In Deutschland nimmt die Zahl der invasiven oder potenziell invasiven Pflanzenarten zu, deren Ausbreitung erhebliche ökologische Schäden verursacht. Ziel dieser Arbeit ist die Entwicklung prädiktiver Habitatmodelle, welche sowohl klimatische und andere
abiotische Faktoren als auch Habitattypen als Umweltvariablen integrieren. Die Habitattypen wurden aus einer fernerkundlichen Klassifikation des Zielgebiets unter Verwendung von MODIS-Oberflächenreflexionsdaten und einem Ensemble von drei Machine-Learning-Algorithmen abgeleitet. Dabei wurden naturnahe Gebiete anhand ihrer spektralen Ähnlichkeit mit Natura-2000-Lebensraumtypen einer von 18 Klassen zugeordnet. Die Klassifizierung ermöglichte es, quantitative Informationen über die räumliche Verteilung von Lebensräumen zu gewinnen und zwischen Störungsereignissen und graduellen Verschiebungen der Habitatzusammensetzung zu unterscheiden. Im Anschluss wurden Artverbreitungsmodelle für 46 invasive Pflanzenarten entwickelt, um potenziell geeignete Lebensräume unter gegenwärtigen und zukünftigen klimatischen Bedingungen mithilfe zweier Machine-Learning-Algorithmen zu ermitteln. Als Prädiktorvariablen wurden insgesamt 18 Umweltfaktoren verwendet, darunter Bodentyp, Höhe, Landnutzung, Habitattyp, Verkehrsinfrastruktur, Temperatur und Niederschlag. Die Modelle legen nahe, dass die Mehrheit der Arten ihren potenziell geeigneten Lebensraum noch nicht besetzt hat. Unter zukünftigen Klimabedingungen ist für die meisten Arten eine Zunahme der Habitateignung zu erwarten. Dabei üben Klimafaktoren, Bodentyp und Verkehrsinfrastruktur den größten relativen Einfluss auf die Artverbreitung aus. Der Habitattyp ist lediglich für eine geringe Zahl von Arten von Bedeutung, was darauf hindeutet, dass es nur begrenzt möglich ist, interspezifische Konkurrenz oder nicht näher spezifizierte biotische Interaktionen in diesem Maßstab zu berücksichtigen. Monitoring-Systeme stellen das kosteneffizienteste Mittel zur Verhinderung der Ausbreitung invasiver Arten dar und sind somit ein entscheidendes Element für deren Management. Auf Basis der Ergebnisse dieser Arbeit wurde eine öffentlich zugängliche Monitoring-Website entwickelt, IPS Monitor, welche digitale Webkarten sowie Pflanzensteckbriefe beinhaltet.Invasive plant species, characterised by high reproductive capacity and broad environmental tolerance, often outcompete native flora, leading to biodiversity loss and economic costs. Due to increasing global trade and climate change, the dynamics of biological invasions are expected to increase in the future. In Germany, the number of invasive or potentially invasive plant species is increasing, causing significant damage due to their aggressive spread and ecological threats. This thesis aims to develop predictive habitat models that integrate climatic and other abiotic factors as well as habitat types as environmental variables. Habitat types were derived from a remote sensing classification of the target area using MODIS surface reflectance data and an ensemble of three machine learning algorithms, assigning natural areas to one of 18 classes based on their similarity to Natura 2000 habitat types. The classification framework was able to provide quantitative information on the spatial distribution of habitats and differentiate between disturbance events and gradual shifts in ecosystem composition. Large-scale species distribution models of 46 invasive plant species were then developed to identify the potentially suitable habitat under present and future climatic conditions using two machine learning techniques. A total of 18 environmental variables were used as predictor variables, including soil type, altitude, land use, habitat type, transport infrastructure, temperature and precipitation. The models indicate that the majority of species have not yet occupied their potentially suitable habitat. An increase in habitat suitability under predicted climatic conditions is implied for most species, with climate factors, soil type and
transport infrastructure having the greatest relative influence on habitat suitability. Habitat type is only relevant for few species, indicating a limited ability to map interspecific competition or unspecified biotic interactions at this spatial scale. As the most cost-effective means of preventing the spread of invasive species, monitoring systems represent a crucial element in their management and enable early detection and rapid response mechanisms. Therefore, a publicly accessible monitoring tool, IPS Monitor, including digital web maps and plant fact sheets has been developed from the results of this thesis
A Multi-Method Approach to Environmental Change and Carbon Storage: Advances in Wetland Geoarchaeology at the Late Neolithic Settlement Site of Pestenacker, Bavaria
No full textWetlands play a crucial role not only as significant carbon sinks but also as natural archives of environmental and cultural history. However, investigating wetland sediments is challenging due to their complex stratigraphy and sensitive waterlogged conditions, requiring a specialised approach to subsurface exploration.
This thesis investigates a unique wetland site using a multi-method approach that combines Electromagnetic Induction (EMI), Electrical Resistivity Tomography (ERT), Direct Push (DP) sensing, and core drilling. The research comprehensively analyses the Holocene depositional history and evaluates the carbon storage capacity of the Verlorener Bach and Loosbach valley in the Bavarian Alpine foothills, with a focus on the Late Neolithic wetland settlement of Pestenacker, a UNESCO World Heritage site.
i) Three primary stratigraphic units were identified: Pleistocene gravel deposits (unit I), organic- rich peat layers with freshwater carbonates (unit II), and overbank deposits with associated redeposited carbonates (unit III). EMI and ERT provided high-resolution spatial and vertical insights into the distribution and thickness of these units, leading to the creation of a validated 3D model of sediment stratigraphy. This revealed key transitions, including a significant Mid Holocene hydrological shift that halted peat formation in unit II.
ii) Hydrological changes during the Mid Holocene were particularly influential in shaping the valley's stratigraphy. Increased precipitation and groundwater levels led to stream incision into the valley floor, which caused the drainage of peatlands (unit II) and the deposition of overbank deposits in unit III. These changes interrupted the accumulation of peat in unit II, transforming the landscape from a waterlogged, peat-forming environment into one dominated by fluvial processes and overbank deposits. This hydrological shift not only impacted peat development but also contributed to the environmental conditions that allowed for the Neolithic settlement of Pestenacker.
iii) Geochemical analysis quantified the Total Carbon (TC) and Total Organic Carbon (TOC) stored in unit II and III. The peat layers in unit II were found to contain an estimated 43 kt of TC and 35 kt of TOC across the 15-hectare study area. These high carbon values highlight the importance of the peatlands as significant carbon sinks, due to their ability to store large amounts of organic material. The carbon content of the peat is closely linked to the waterlogged conditions that prevent the oxidation and decomposition of organic matter. These findings not only emphasize the role of this wetland in carbon storage but also underline its vulnerability to environmental changes that can lead to carbon release.:Acknowledgements
Abstract
Kurzfassung
Table of content
List of Figures
List of Tables
Acronyms and Symbols
1. Introduction
1.1 Investigating Wetlands – Significances, Challenges and Advancements
1.1.1 Importance of Wetlands as Environmental and Cultural Archives
1.1.2 Challenges in Investigating Wetlands
1.1.3 Multi-Method Investigation Approach
1.2 The Study Site
1.2.1 The Neolithic Settlement Site of Pestenacker
1.2.2 Geographical setting
1.3 Thesis Objectives
2. Published Studies
2.1 Compilation of different data sets of the Late Neolithic wetland site of Pestenacker and of the adjacent valley depositions
2.2 A hydrological tipping point and onset of Neolithic wetland occupation in Pestenacker (Lech catchment, S Germany)
2.3 Determining carbon storage of a complex peat stratigraphy using non- and minimal-invasive geophysical prospection techniques (Verlorener Bach and Loosbach valleys, southern Germany)
3. Discussion
3.1 Methodological Advancements: The Strength of a Multi-Method Approach
3.2 Stratigraphic Evolution of the Study Area
3.2.1 First stratigraphic shift: From the Pleistocene to the Early Holocene
3.2.2 Second stratigraphic Shift: The Mid Holocene Hydrological Tipping Point
3.3 Carbon Storage in Wetlands
3.4 Future Research Directions
3.4.1 Enhanced Direct Push Capabilities
3.4.2 Future Directions in Geoarchaeological Methods in Pestenacker
3.4.3 Long-term Monitoring of Hydrological Dynamics
4. Conclusion
References
Appendix
A1 Summary of the Thesis
A2 Author's List of Publications
A3 Information of the Thesis and Overview of included contributions
A4 Declaration of Independent Work
A5 Bibliographic Description
A6 Curriculum VitaeFeuchtgebiete spielen eine zentrale Rolle, nicht nur als bedeutende Kohlenstoffsenken, sondern auch als natürliche Archive für Umwelt- und Kulturgeschichte. Die Untersuchung von Feuchtbodensedimenten ist jedoch aufgrund ihrer komplexen Stratigraphie und empfindlichen, wasserreichen Bedingungen eine Herausforderung und erfordert angepasste Erkundungsmethoden.
Diese Arbeit untersucht ein besonderes Feuchtgebiet mithilfe eines multimethodischen Ansatzes, der die Ergebnisse der elektromagnetischen Induktion (EMI), der elektrischen Widerstandstomographie (ERT), der Direct-Push-Technologie und klassischer Bohrkernuntersuchungen kombiniert. Die Studie analysiert umfassend die holozäne Talentwicklung und bewertet das Kohlenstoffspeicherpotenzial des Talsystems des Verlorenen Bachs und Loosbachs im bayerischen Alpenvorland. Im Fokus steht dabei die jungneolithische Feuchtbodensiedlung Pestenacker, eine UNESCO-Weltkulturerbestätte.
i) Es werden drei primäre stratigraphische Einheiten identifiziert: pleistozäne glazi-fluviale Kiese (unit I), Niedermoortorfe mit Frischwassercarbonaten (unit II) und Überflutungssedimenten (unit III). Mithilfe von EMI und ERT lassen sich hochauflösende räumliche und vertikale Einblicke in die Verteilung und Mächtigkeit dieser Einheiten gewinnen, was zur Erstellung eines validierten 3D- Modells der Sedimentstratigraphie führt. Dabei werden bedeutende Übergänge sichtbar, darunter ein Kipppunkt im Mittleren Holozän, der die Torfbildung in unit II zum Stillstand bringt.
ii) Die hydrologischen Veränderungen während des Mittleren Holozäns hatten einen besonders starken Einfluss auf die Entwicklung der Talstratigraphie. Erhöhte Niederschläge und steigende Grundwasserstände führten zur Eintiefung der Bäche in den Talboden, was die Entwässerung der Niedermoortorfe und die Ablagerung der Sedimente in unit III zur Folge hat. Diese Veränderungen beenden die Torfbildung in unit II und verwandelten die Landschaft von einem wasserreichen Niedermoor in ein von Überflutungssedimenten und Flussaktivitäten geprägtes Gebiet. Dieser hydrologische Wandel schuf die Umweltbedingungen, die es den Menschen der Altheimer Kultur ermöglichen, in diesem Gebiet zu siedeln.
iii) Geochemische Analysen zeigen, dass die Torfschichten in unit II schätzungsweise 43 kt an Kohlenstoff (TC) und 35 kt an organischen Kohlenstoff (TOC) auf der 15 Hektar großen Untersuchungsfläche speichern. Diese hohen Kohlenstoffgehalte unterstreichen die Bedeutung der Niedermoortorfe als Kohlenstoffsenken, da sie in der Lage sind, große Mengen organischen Materials zu speichern. Der Kohlenstoffgehalt des Torfs ist eng mit den wasserreichen Bedingungen verknüpft, die die Oxidation und den Abbau organischer Substanzen verhindern. Diese Ergebnisse betonen nicht nur die Rolle dieses Feuchtgebietes bei der Kohlenstoffspeicherung, sondern auch seiner Anfälligkeit gegenüber Umweltveränderungen, die zur Freisetzung von gespeichertem Kohlenstoff führen könnten.:Acknowledgements
Abstract
Kurzfassung
Table of content
List of Figures
List of Tables
Acronyms and Symbols
1. Introduction
1.1 Investigating Wetlands – Significances, Challenges and Advancements
1.1.1 Importance of Wetlands as Environmental and Cultural Archives
1.1.2 Challenges in Investigating Wetlands
1.1.3 Multi-Method Investigation Approach
1.2 The Study Site
1.2.1 The Neolithic Settlement Site of Pestenacker
1.2.2 Geographical setting
1.3 Thesis Objectives
2. Published Studies
2.1 Compilation of different data sets of the Late Neolithic wetland site of Pestenacker and of the adjacent valley depositions
2.2 A hydrological tipping point and onset of Neolithic wetland occupation in Pestenacker (Lech catchment, S Germany)
2.3 Determining carbon storage of a complex peat stratigraphy using non- and minimal-invasive geophysical prospection techniques (Verlorener Bach and Loosbach valleys, southern Germany)
3. Discussion
3.1 Methodological Advancements: The Strength of a Multi-Method Approach
3.2 Stratigraphic Evolution of the Study Area
3.2.1 First stratigraphic shift: From the Pleistocene to the Early Holocene
3.2.2 Second stratigraphic Shift: The Mid Holocene Hydrological Tipping Point
3.3 Carbon Storage in Wetlands
3.4 Future Research Directions
3.4.1 Enhanced Direct Push Capabilities
3.4.2 Future Directions in Geoarchaeological Methods in Pestenacker
3.4.3 Long-term Monitoring of Hydrological Dynamics
4. Conclusion
References
Appendix
A1 Summary of the Thesis
A2 Author's List of Publications
A3 Information of the Thesis and Overview of included contributions
A4 Declaration of Independent Work
A5 Bibliographic Description
A6 Curriculum Vita
Franz Metz, In E-Dur. Otto Sykora und die heitere Musikgeschichte des Banater Berglands, München: Edition Musik Südost, 2023. 288 S., Abb.
No full textProphylactic Human Papillomavirus Vaccination: From the Origin to the Current State
No full textImmunization is the most successful method in preventing and controlling infectious
diseases, which has helped saving millions of lives worldwide. The discovery of the human papillomavirus
(HPV) infection being associated with a variety of benign conditions and cancers has driven
the development of prophylactic HPV vaccines. Currently, four HPV vaccines are available on the
pharmaceutical market: Cervarix, Gardasil, Gardasil-9, and the recently developed Cecolin. Multiple
studies have proven the HPV vaccines’ safety and efficacy in preventing HPV-related diseases. Since
2006, when the first HPV vaccine was approved, more than 100 World Health Organization member
countries reported the implementation of HPV immunization. However, HPV vaccination dread,
concerns about its safety, and associated adverse outcomes have a significant impact on the HPV
vaccine implementation campaigns all over the world. Many developed countries have successfully
implemented HPV immunization and achieved tremendous progress in preventing HPV-related
conditions. However, there are still many countries worldwide which have not created, or have
not yet implemented, HPV vaccination campaigns, or have failed due to deficient realization plans
associated with establishing successful HPV vaccination programs. Lack of proper HPV information
campaigns, negative media reflection, and numerous myths and fake information have led to HPV
vaccine rejection in many states. Thus, context-specific health educational interventions on HPV
vaccination safety, effectiveness, and benefits are important to increase the vaccines’ acceptance for
efficacious prevention of HPV-associated conditions