Cologne Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases
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Systematics, evolutionary distinctiveness, and conservation priority of the speciose lizard genus Cyrtodactylus in Vietnam
Get PDFCyrtodactylus is the most diverse genus in the family Gekkonidae and ranks as the third-largest vertebrate genus in the world. In the past two decades, the number of new species has increased more than fourfold, particularly with a significant surge in new discoveries in Vietnam. However, as new species in this genus are described at a rapid rate, several taxa have been synonymized as a result of additional data. For example, C. paradoxus and C. thochuensis have been shown to be junior synonyms of C. condorensis and C. leegrismeri, respectively. This highlights the pressing need to review the taxonomic progress. Moreover, many areas in Vietnam where this group likely occurs are still poorly studied, emphasizing the necessity for additional field surveys to better understand the diversity of Cyrtodactylus in these regions.
Furthermore, although some phylogenetic relationships and biogeographic studies have been conducted, phylogenetic analyses have yet included all members of the genus in Vietnam. Previous studies have primarily focused on just one or two mitochondrial genes (COI and/or ND2). Additionally, since the beginning of the dissertation, only one study has been carried out that provides information on the population status and main anthropogenic threats to one threatened species, and none of the Cyrtodactylus species, especially the most threatened taxa, have been investigated for their microhabitat preferences. Therefore, we conducted this study to (1) investigate the taxonomic status of described Cyrtodactylus species in Vietnam and discover new taxa (2) recover phylogenetic relationships, evolutionary processes, and biogeographic history of Cyrtodactylus and (3) assess ecological traits and population status of two endemic and critically endangered species.
The results of the dissertation show that C. thuongae and C. rufford are junior synonyms of C. dati and C. lomyenensis, respectively. During four years of this study, seven new species have also been described and at least ten new lineages have been discovered. Our study reveals that the C. angularis and C. chauquangensis are monophyletic groups and several lineages within these groups diverged during the Miocene era when the East Asia monsoon was developed and increased precipitation in the region. Biogeographic analysis suggests that the Mekong Lowlands is likely the ancestral area of the C. angularis group while C. chauquangensis might have originated from the Northwest Uplands (including northern Laos and part of northern Vietnam).
Our ecological analyses confirm that C. takouensis is a granite specialist. In contrast, C. gialaiensis likely has a broader distribution across the Gia Lai District rather than restricted to a single locality. It has had to adapt to various habitats, including soil cliffs, tree trunks, and shrubs found between coffee plantations and roads, as well as within coffee plantation areas. Recognizing the significance of demographic information for species conservation, population monitoring studies were conducted to estimate the population size of two Vietnamese Cyrtodactylus species, namely, C. takouensis and C. gialaiensis. According to the study results, their population size and density are extremely
small and negatively correlated with the increasing severity of human impacts. The diet of C. nigriocularis was also for the first time investigated in this study to support ex situ conservation measures.
To provide a reference for future studies, we also assess the suitability of genetic markers for molecular systematics and species identification of Cyrtodactylus based on twelve complete mitochondrial genomes of ten Cyrtodactylus species. Overall, phylogenies inferred from ND5 most frequently recovered a topology similar to those based on the 13 protein coding genes.
In conclusion, this study helps clarify issues related to the systematics and species diversity, and provide robust phylogenetic relationships, evolutionary hypotheses, and successfully reconstruct biogeographic history for two Cyrtodactylus groups, namely the C. angularis and C. chauquangensis groups. Together with assessments of ecology, demography and anthropogenic threats, the dissertation highlights the urgent need of conservation actions for at least two threatened species, C. gialaiensis and C. takouensis
Kritisches Denken in der Chemielehrer*innenbildung - Eine konzeptionell-empirische Studie zur Integration und Operationalisierung
Get PDFVulnerability, Cognition and Resilience in Cannabis Consumers: A comparison across healthy and psychosis groups
Get PDFCannabis is one of the most widely used drugs globally. The increasing consumption
underscores the necessity of research into its effects and consequences.. Cannabis-induced
psychosis (CIP) is one of the possible consequences of using cannabis and has received
little research attention.
The risk pathways and cognitive impairments in primary schizophrenia and psychosis are
well established. Risk factors include environmental exposures such as childhood trauma,
bullying, depression and lack of resilience. Cognitive impairment is the most common shared
symptom in psychosis patients. Research into cognitive impairment in healthy Cannabis
Consumers (CC) is mixed and partly contradictory. Some studies suggest that cannabis
consumption has long-lasting negative effects on cognition, while others argue that these
effects disappear after abstinence. The frequency and dose of cannabis also plays an
important role in cognitive impairment. The role of risk factors and cognitive impairment in
CIP remains mostly unclear.
The purpose of this study was to compare cognitive impairment, resilience and the
vulnerability factors of childhood trauma, bullying, depression, and an environmental risk
score for psychosis between n = 49 Cannabis-induced psychosis (CIP) patients, n = 70
recent-onset psychosis (ROP) patients, n = 120 healthy controls (HC), and n = 25 healthy
cannabis consumers (CC). Behavioural data was collected through standardised selfreporting questionnaires: the Resilience Scale for Adults (RSA), the Beck Depression
Inventory II (BDI-II), the Childhood Trauma Questionnaire (CTQ), and the Bullying Scale
(BS). Using the questionnaire manuals, subdomains and total scores were calculated. The
exposome score for schizophrenia (EC-SCZ) calculates a sum score of weighted exposure
factors and was calculated based on the factors cannabis use, winter birth, childhood trauma
and bullying. Neurocognitive data was collected using the PRONIA neurocognitive test
battery. The cognitive subdomains of Social Cognition, Speed of Processing, Working
Memory, Verbal Learning, and Attention were calculated, as well as a global cognition score.
Two-way ANOVAS with the factors cannabis and psychosis were used to compare the four
study groups. Based off previous research in psychosis and cannabis, we expected CIP,
ROP, and CC to show less resilience, more vulnerability factors and more cognitive
impairment than HC.
Results showed that cognitive impairment was only associated with the presence of
psychosis (global cognition: F(1, 260) = 75.698, p < 0.001). This is in line with existing
research about cognitive impairment in schizophrenia. Unlike most previous research, CC
showed no cognitive impairment compared to HC, ROP or CIP. Interaction of cannabis and
psychosis was associated with higher depression scores (F(1, 251) = 5.768, p = 0.017),
higher emotional abuse scores (F(1, 245) = 7.151, p = 0.008) and a lack of social resources11
(F(1, 244) = 27.640, p < 0.001) as part of an overall lack of resilience (F(1, 228) = 4.133, p =
0.043). These interactions might point towards these vulnerability factors being more specific
risk pathways for CIP, than just overall psychosis. Longitudinal data would be needed to
further establish causal links between suggested risk pathways and CIP. This might help to
establish prevention programs specifically for CIP
Bleichen und Infiltration mit niedrigviskösem Kunststoff zur Maskierung fluorotischer Läsionen an Frontzähnen: Eine systematische Übersichtsarbeit und Metaanalyse
Get PDFDie dentale Fluorose ist eine entwicklungsbedingte Schmelzstörung der Zähne, die durch eine übermäßige Fluoridaufnahme während der Zahnentwicklung verursacht wird. Sie äußert sich typischerweise in weißen bis bräunlichen Verfärbungen oder strukturellen Defekten des Zahnschmelzes. Insbesondere bei stark ausgeprägten Läsionen kann die dentale Fluorose die mundgesundheitsbezogene Lebensqualität erheblich beeinträchtigen. Zur Steigerung der Zufriedenheit der Patient*innen und zur Verbesserung der ästhetischen Wahrnehmung ist es das Ziel geeigneter Behandlungsansätze, eine homogene Zahnfarbe zu erzielen und fluorotische Läsionen wirksam zu maskieren. Daher kommt der Evaluation effektiver Therapieoptionen und möglicher Behandlungskombinationen eine besondere Bedeutung zu. Ziel der vorliegenden Studie ist es daher, die maskierende Wirksamkeit von Bleichen und Infiltration – sowohl als Einzeltherapie als auch in Kombination – bei der Behandlung fluorotischer Läsionen im Frontzahnbereich von Jugendlichen und Erwachsenen zu analysieren. Im Rahmen der Studie wurde eine systematische Literaturrecherche zur Behandlung fluorotischer Läsionen in den einschlägigen medizinischen Datenbanken PubMed, Cochrane Library und Embase durchgeführt. Als primärer Outcome wurde die Anzahl der maskierten Zähne definiert. Ein Zahn galt als maskiert, wenn der Farbunterschied (ΔE) zwischen fluorotischen Bereichen und gesundem Zahnschmelz einen Wert von ΔE ≤ 3,7 aufwies. Sekundäre Outcomes umfassten die durchschnittlichen ΔE-Werte zwischen fluorotischem und gesundem Zahnschmelz zu Studienbeginn sowie nach der Behandlung, ebenso wie die Auswirkung der jeweiligen Therapie auf die Zufriedenheit der Patient*innen. Die Behandlungsergebnisse der Interventionen – Bleichen, Infiltration sowie die Kombination aus Bleichen und anschließender Infiltration – wurden mittels Metaanalysen unter Anwendung eines Random-Effects-Modells (RE-Modell) verglichen. Die Bewertung des Verzerrungspotenzials (Bias) erfolgte mithilfe des ROBINS-I-tools. Es wurden vier Studien mit insgesamt 230 fluorotischen Frontzähnen bei 47 Patient*innen in die Analyse eingeschlossen. Sowohl das Bleichen (Erfolgsrate: 0,20; 95%-CI: 0,10–0,39) als auch die Infiltration (0,31; 95%-CI: 0,06–0,56) führten zu einer Maskierung fluorotischer Läsionen im Frontzahnbereich. Die Kombination beider Verfahren erzielte eine signifikante Reduktion des Farbunterschieds (0,75; 95%-CI: 0,44–1,06). Unterschiede in den Behandlungsprotokollen sowie die Variabilität des Fluorose-Schweregrads werden als mögliche Einflussfaktoren auf den Maskierungserfolg diskutiert. Alle untersuchten Therapieansätze führten zu einer Reduktion der durchschnittlichen ΔE-Werte zwischen fluorotischem und gesundem Zahnschmelz sowie zu einer Zufriedenheit von Patient*innen. Die Ergebnisse der Metaanalyse legen nahe, dass die Infiltration in Kombination mit vorausgehendem Bleichen fluorotische Läsionen im Frontzahnbereich effektiver kaschiert als die Einzeltherapien. Auf Basis der vorliegenden Daten kann die Kombinationstherapie als bevorzugte Behandlungsoption bewertet werden
Popmusikforschung. Zehn Perspektiven auf Billie Eilish
No full textWie kann Popmusik erforscht werden? Unterhaltsam und leicht verständlich führen die Autor:innen in die Vielfältigkeit der Popular Music Studies ein. Im Mittelpunkt steht ein gemeinsames Beispiel, das aus verschiedenen Perspektiven beleuchtet wird: Billie Eilishs »Bad Guy«. Zehn kompakte Kapitel vermitteln ein grundlegendes Verständnis der Popmusikforschung und ihrer methodischen Werkzeuge. Der mosaikartige Aufbau dieser Einführung unterstützt nicht nur Studierende der Musik- und Kulturwissenschaften, sondern auch Praktiker:innen aus Musikbranche und Journalismus bei der Entwicklung eigener Analysekompetenzen zu einem kulturellen Phänomen, das allgegenwärtig ist und die Massen begeistert
Setup of a densely distributed and quality-controlled meteorological sensor network in Pune, India, for urban microclimate research and citizen participation in the context of climate change adaptation
No full text
Developing luminescence-based inventories to decipher particle histories in hyperarid alluvial landforms (Atacama Desert, Chile)
No full textDeciphering particle histories in hyperarid alluvial landforms is crucial to reconstruct depositional and post-depositional dynamics. This is essential to understand landscape evolution and climatic variability in the Late Quaternary. In the Atacama Desert, the driest non-polar desert on Earth, such reconstructions are scarce since suitable chronological tools are lacking. Organic material for 14C dating is usually absent and cosmogenic nuclide dating methods cannot resolve subsurface processes related to post-depositional mixing. Single-grain feldspar luminescence dating can overcome those challenges, as feldspar grains are abundant and can record both deposition and post-depositional processes. However, this method also has limitations: Atacama Desert feldspars i) display unfavourable luminescence properties, ii) have heterogeneous geochemical compositions, and iii) experience heterogeneous bleaching, which is common in alluvial deposits.
This thesis presents methodological refinements of single-grain feldspar luminescence dating techniques. These techniques are tested by applying them to decipher particle histories along a climatic and elevational transect in the Coastal Cordillera of the Atacama Desert. The overall aim is to establish a chronological toolset for complex alluvial settings in hyperarid regions and to apply it to improve the understanding of palaeoclimatic variability and landscape evolution in the Coastal Cordillera.
The challenging luminescence properties of Atacama Desert feldspars result in time-consuming measurements, as many grains have to be analysed to obtain a sufficient number of suitable luminescence signals. In a first study the application of a standardised growth curve (SGC) was successfully tested on Atacama Desert samples. Measurement times were reduced by at least 60 %. It was further shown that the geochemical composition of feldspar grains is not correlated with their luminescence characteristics. This finding motivated a second study of the internal potassium (K) concentration of feldspar and its effects on dose rate calculations. A comparison of the three most cited literature-based values with measurement-based K-concentrations revealed that literature values overestimate the K-concentration in nine out of ten analysed samples. This results in systematic one-directional errors in the dose rate determination and consequently in the age calculation. To address this, a time- and cost-efficient approach was developed to routinely measure the
K-concentration in feldspar for luminescence dating. In the third study of this thesis, this approach was successfully applied to samples from alluvial deposits along the climatic and elevational transect in the Atacama Desert. However, the SGC approach yielded unreliable results when applied to these samples. Therefore, in the third study a conventional single-aliquot regenerative-dose (SAR) approach was used for equivalent dose (De) estimations. The luminescence analyses were integrated into a multi-method framework that included granulometric and geochemical analyses as well as field surveys. Five soil and surface profiles along the climatic and elevational transect were examined. Depositional phases as well as post-depositional processes, including bioturbation and desert pavement formation, were identified. The results indicate wetter phases around 50 ka and since 5 ka, as well as prolonged geomorphic stability under presumably extremely arid conditions around 6 ka. These reconstructions are consistent with other palaeoenvironmental archives from the region and suggest a strong influence of regional climate variability, likely linked to (ENSO-related) weather anomalies.
Overall, this thesis demonstrates that in complex alluvial landforms, which are prone to heterogeneous bleaching and contain feldspars with heterogeneous chemical compositions, special precautions are required. Dose rates must be determined accurately, accounting for variable internal K-concentrations. Furthermore, luminescence results must be interpreted holistically. This involves considering the shape of De distributions, age estimates, luminescence-related proxies, and geomorphological evidence, rather than focussing on a single age per sample. Applied in this way, single-grain feldspar luminescence dating provides a robust tool to decipher particle histories and thereby reconstruct the paleoenvironment, thus contribution to an improved understanding of Late Quaternary climatic fluctuations and landscape evolution in the hyperarid Atacama Desert