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Unplanned 30-Day Readmission in Glioblastoma Patients: Implications for the Extent of Resection and Adjuvant Therapy
No full textBackground: Unplanned early readmission (UER) within 30 days after hospital release is a
negative prognostic marker for patients diagnosed with glioblastoma (GBM). This work analyzes the
impact of UER on the effects of standard therapy modalities for GBM patients, including the extent of
resection (EOR) and adjuvant therapy regimen. Methods: Records were searched for patients with
newly diagnosed GBM between 2014 and 2020 who were treated at our facility. Exclusion criteria
were being aged below 18 years or missing data. An overall survival (OS) analysis (Kaplan–Meier
estimate; Cox regression) was performed on various GBM patient sub-cohorts. Results: A total of
276 patients were included in the study. UER occurred in 13.4% (n = 37) of all cases, significantly
reduced median OS (5.7 vs. 14.5 months, p < 0.001 by logrank), and was associated with an increased
hazard of mortality (hazard ratio 3.875, p < 0.001) in multivariate Cox regression when other clinical
parameters were applied as confounders. The Kaplan–Meier analysis also showed that patients
experiencing UER still benefitted from adjuvant radio-chemotherapy when compared to radiotherapy
or no adjuvant therapy (p < 0.001 by logrank). A higher EOR did not improve OS in GBM patients
with UER (p = 0.659). Conclusion: UER is negatively associated with survival in GBM patients. In
contrast to EOR, adjuvant radio-chemotherapy was beneficial, even after UER
African Socialism – A Blueprint for Secular State Formation at the Time of Independence
No full textIt has long been argued that “Africans” are supposedly “incurably” or “notoriously” religious. More specifically, traditional religions in Africa are regarded as operating outside of a secular framework, such as that which has been implemented in “Western democracies.” Recent studies, however, highlight a marked rise in religiosity, especially Pentecostalism and Salafism, and the loss of secularism and secular institutions in Africa. This leads us to question the inevitability of African religiosity, rendering implausible any claim that the continent has always been fundamentally religious. Indeed, at the time of their independence, many countries implemented socialist policies, with strongly secularist regimes in power. Considering whether the public sphere in African countries, or even the entire African population, is ‘more religious’ or ‘more secular’ is overly simplistic. It is necessary to instead scrutinise the motivations for differentiating between the religious and secular spheres, as well as any historical changes to the boundary between them. The concept of multiple secularities provides an analytical framework through which the boundary work between religious and secular spheres may be brought into focus. I will argue that, in most African countries, secularity was driven by the need to balance religious (and ethnic) diversity, and integrate the populations of the artificially created colonial states, after independence. In this paper, I reconstruct the relationship between institutions, social formations, cultural values, and ideologies, along the religious-secular divide, at the crucial time of state formation and independence
Facile Synthesis of Enantiomerically Pure P-Chiral 1-Alkoxy-2,3-dihydrophospholes via Nucleophilic P-N Bond Cleavage of a 1-Phospha-2-azanorbornene
No full textThe reactive P N bond in a racemic mixture of
endo-1-phospha-2-azanorbornene (PAN) (RP/SP)-endo-1 is
readily cleaved with enantiomerically pure lithium alkoxides
followed by protonation to afford diastereomeric mixtures of
P-chiral 1-alkoxy-2,3-dihydrophosphole derivatives. The iso-
lation of these compounds is rather challenging due to the
reversibility of the reaction (elimination of alcohols). However,
methylation of the sulfonamide moiety of the intermediate
lithium salts and sulfur protection of the phosphorus atom
prevent the elimination reaction. The resulting air-stable P-
chiral diastereomeric 1-alkoxy-2,3-dihydrophosphole sulfide
mixtures can be readily isolated and fully characterized. The
diastereomers can be separated by crystallization. The 1-
alkoxy-2,3-dihydrophosphole sulfides are readily reduced with
Raney nickel to afford phosphorus(III) P-stereogenic 1-alkoxy-
2,3-dihydrophospholes with potential use in asymmetric
homogeneous transition metal catalysis
Aging and Fracture Resistance of Implant-Supported Molar Crowns with a CAD/CAM Resin Composite Veneer Structure
No full textChipping of implant-supported molar crowns (iSCs) is a frequently reported complication.
This study aimed to investigate the in-vitro aging and fracture resistance of iSCs with a CAD/CAM
resin composite veneer structure fabricated with the Rapid Layer Technology (RLT) approach. Eight
iSCs per group were fabricated by using two different CAD/CAM resin composites (Shofu Block
HC: SH; Grandio blocs: GB) for veneer structures, and zirconia (ZrO2), polyetheretherketone (PEEK),
and cobalt–chromium (CoCr; control) as framework materials. The surfaces to be bonded were
sandblasted, cleaned in an ultrasonic bath, and a coupling agent was applied. A self-adhesive resin
luting composite was used to adhesively lute the veneer structures to the frameworks. The crowns
were semi-permanently cemented to the abutments. After storage in deionized water, iSCs were
loaded in a chewing simulator (TCML, 10,000 thermal cycles 5 ◦C to 55 ◦C for 20 s, 1.2 million,
loading force 50 N). Four ZrO2 and one CoCr crown did not survive the TCML. The fracture force
was determined after 24 h storage in deionized water and yielded values of ≥974 N. Lowest fracture
forces were yielded in the PEEK-SH group in comparison to CoCr or ZrO2 groups (p ≤ 0.031). For
identical framework materials, no significant influence of the veneering material was observed. All
PEEK-GB frameworks fractured, and chipping occurred for ZrO2-SH and all CoCr frameworks.
PEEK-SH and ZrO2-GB presented both chipping and framework fractures. Within the limitations of
this in-vitro study, the RLT with a CAD/CAM resin composite veneer structure might be a promising
approach to veneer iSCs. Yet, the choice of the CAD/CAM resin composite and of the framework
material determine the fracture resistance
In situ studies on the industrial production process for molybdenum dioxide, MoO2
No full textIn the industrial production of molybdenum the reduction of molybdenum trioxide with hydrogen is a two-step process. In order to get a deeper understanding of the chemistry involved, in situ studies were performed on the thermal behavior of molybdenum trioxide and the first reduction step to molybdenum dioxide. MoO3 shows a very strong anisotropy for thermal expansion (linear expansion coefficients α in 10−4 K−1: 1.32(4) for a, 5.5(1) for b, −0.246(5) for c). Upon heating in air, preferred orientation in XRPD patterns decreases and the color changes from grey to yellow, probably caused by decreasing oxygen vacancy concentration. The reduction of MoO3 by hydrogen was investigated via in situ X-ray powder diffraction for varying heating rate, hydrogen flow and potassium content. The formation of the intermediate γ-Mo4O11 shows a higher rate for increasing potassium content; it does not play a role whether potassium is present in the starting material MoO3 or in MoO2 formed in the reaction. The high-temperature modification of K2MoO4 was found to crystallize in the α-K2SO4 type (P63/mmc, a=6.3463(2) Å, c= 8.1331(2) Å). Heating up MoO3 in vacuum (1 Pa) with the same T,t protocol as above yields MoO2 even without the presence of hydrogen
Carbon–biodiversity relationships in a highly diverse subtropical forest
No full textCarbon-focused climate mitigation strategies are becoming increasingly important in forests. However, with ongoing biodiversity declines we require better knowledge of how much such strategies account for biodiversity. We particularly lack information across multiple trophic levels and on established forests, where the interplay between carbon stocks, stand age, and tree diversity might influence carbon–biodiversity relationships. Using a large dataset (>4600 heterotrophic species of 23 taxonomic groups) from secondary, subtropical forests, we tested how multitrophic diversity and diversity within trophic groups relate to aboveground, belowground, and total carbon stocks at different levels of tree species richness and stand age. Our study revealed that aboveground carbon, the key component of climate-based management, was largely unrelated to multitrophic diversity. By contrast, total carbon stocks—that is, including belowground carbon—emerged as a significant predictor of multitrophic diversity. Relationships were nonlinear and strongest for lower trophic levels, but nonsignificant for higher trophic level diversity. Tree species richness and stand age moderated these relationships, suggesting long-term regeneration of forests may be particularly effective in reconciling carbon and biodiversity targets. Our findings highlight that biodiversity benefits of climate-oriented management need to be evaluated carefully, and only maximizing aboveground carbon may fail to account for biodiversity conservation requirements
Handschriften und Urkunden der Stadtbibliothek Leipzig in der Universitätsbibliothek Leipzig: Neuzugänge nach 1838: Bearbeitet von Thomas Fuchs
No full textDie Stadtbibliothek Leipzig gehört zu den traditionsreichen und bedeutenden städtischen Bibliotheken mit herausragenden, wissenschaftlich bedeutsamen Altbeständen. Ihr Ursprung reicht bis in das 15. Jahrhundert zurück. Ihre historischen Sondersammlungen werden seit 1962 als Depositum an der Universitätsbibliothek Leipzig aufbewahrt. Die abendländischen Handschriften wurden 1837 bis 1840 in einem gedruckten Katalog nachgewiesen. Die nach 1838 neu in den Bestand gelangten abendländischen Handschriften und Urkunden waren bisher nur in einem nach Zugangsjahr geordneten handschriftlichen Zuwachsverzeichnis nachgewiesen. Deshalb ist der Bestand der Forschung weitgehend unbekannt geblieben. Durch diesen Katalog werden diese Dokumente erstmals wissenschaftlich beschrieben. Formal und inhaltlich verzeichnet sind rund 600 Handschriften, Urkunden und umfangreiche Autographen- und Briefsammlungen. Register der Orte, Personen, Sachen und Körperschaften erschließen die Texte. Sie umspannen einen Zeitraum vom 14. bis zur Mitte des 20. Jahrhunderts mit einem Schwerpunkt vom 17. bis zum 19. Jahrhundert. Der Bestand ist inhaltlich außerordentlich heterogen
Early socio-cognitive development in non-human great apes: A comparative investigation of social influence on memory and belief processing across development
No full textHumans and non-human great apes live in complex multi-individual groups. To be able to navigate such a social environment, individuals have to develop special skills (social cognition). Right after birth,
primates show specific attention biases (social attention) that allow them to attend to the most important (social) stimuli in their environment. These abilities are adaptive as they increase an individual’s fitness
by detecting mating opportunities, but also by learning the most efficient survival mechanisms from others. Especially in the first years of life, human infants undergo major social cognitive developments. In great apes, this period of their development is less well understood, leaving the question unresolved:
at what point do humans and great apes start to differ during development? Social attention – selective and increased attention towards social entities – describes one cognitive phenomenon that may likely
represent the building block for higher-order social cognitive abilities (e.g., joint attention, intention
understanding) and therefore might be a potential candidate for species differences between humans
and non-human great apes. This dissertation aimed to study the influence of social attention on memory and belief processing
during development in non-human great apes (orangutans, gorillas, bonobos, and chimpanzees) and to
develop methods that would allow for reliable cross-species comparisons. Study 1 investigated whether
social stimuli can increase object memory (Social Memory Effect, SME) in four non-human great ape
species and how long-lasting this effect is. Adult great apes (>10 years) showed the strongest SME, as
tested both with looking time (LT) and heart rate (HR) measures, while infant apes (0-5 years) did not show indications of SME. Juveniles’ (6-10 years) SME was in between infants and adults, indicating a
later onset of SME in non-human great apes compared to humans (9 months). After two days, the SME was gone for the adult apes. Study 2 tested whether the (false) belief of a social counterpart would interfere (altercentric influence) with memory for the hiding location of a reward in great apes across development. The results showed that infant great apes were most negatively affected by the false belief, followed by juveniles and adults, who only showed a mild interference in their search behaviour for the hidden reward. The results of this dissertation point toward similarities and differences in the influence of social stimuli on memory and
belief processing between human and non-human great apes.:Abbreviations V
Authorship Note VI
Acknowledgements XVIII
1. Introduction 1
Comparative psychology 3
Social attention in humans 5
Social attention in great apes 9
How to measure social cognitive development in pre- and non-verbal individuals 12
Influence of social stimuli on memory in humans 15
Influence of social stimuli on memory in great apes 17
Influence of social attention on belief processing in humans 18
Influence of social attention on belief processing in great apes 21
Research gaps 23
The focus of this dissertation 24
4. Study 1: Social attention increases object memory in adult but not younger great apes 27
5. Study 2: Great apes show altercentric influences when confronted with conflicting beliefs 45
6. General Discussion 80
Method development for comparative developmental psychology 80
How does the social memory effect develop in great apes? 83
How does social attention influence belief processing during development in great apes? 86
How does this dissertation contribute to the study of comparative psychology? 90
What does this dissertation tell us about the evolution of human-unique cognitive skills? 91
Future directions 92
7. Conclusion 94
References 96
Curriculum Vitae 132
Scientific Publications and Conference Contributions 135
Contributions of Authors 13
Dysregulation of intestinal epithelial electrolyte transport in canine chronic inflammatory enteropathy and the role of the renin-angiotensin-aldosterone-system
No full textChronic diarrhea is a hallmark sign of canine chronic inflammatory enteropathy (CIE), leading to fluid and electrolyte losses. Electrolyte homeostasis is regulated by the renin-angiotensin-aldosterone-system (RAAS), which might be involved in (counter-)regulating electrolyte losses in canine CIE. Whether and which electrolyte transporters are affected or if RAAS is activated in canine CIE is unknown. Thus, intestinal electrolyte transporters and components of the RAAS were investigated in dogs with CIE. Serum RAAS fingerprint analysis by mass spectrometry was performed in 5 CIE dogs and 5 healthy controls, and mRNA levels of intestinal electrolyte transporters and local RAAS pathway components were quantified by RT-qPCR in tissue biopsies from the ileum (7 CIE, 10 controls) and colon (6 CIE, 12 controls). Concentrations of RAAS components and mRNA expression of electrolyte transporters were compared between both groups of dogs and were tested for associations among each other. In dogs with CIE, associations with clinical variables were also tested. Components of traditional and alternative RAAS pathways were higher in dogs with CIE than in healthy controls, with statistical significance for Ang I, Ang II, and Ang 1–7 (all p < 0.05). Expression of ileal, but not colonic electrolyte transporters, such as Na+/K+-ATPase, Na+/H+-exchanger 3, Cl− channel 2, down-regulated in adenoma, and Na+-glucose-cotransporter (all p < 0.05) was increased in CIE. Our results suggest that the dys- or counter-regulation of intestinal electrolyte transporters in canine CIE might be associated with a local influence of RAAS. Activating colonic absorptive reserve capacities may be a promising therapeutic target in canine CIE
Satanismus in der DDR
No full textDie vorliegende Masterarbeit untersucht erstmals systematisch, wie das Ministerium für Staatssicherheit (MfS) das Phänomen „Satanismus“ in der Spätphase der DDR konstruierte, deutete und operativ bearbeitete. Ausgehend von Fällen jugendkultureller Grenzüberschreitungen der Heavy-Metal- und Grufti-Szene wird ein breiter Korpus an Stasi-Unterlagen analysiert, um aufzuzeigen, welche Wissensbestände, Deutungsmuster und bürokratischen Abläufe den Umgang der Behörden mit der Erscheinung prägten. Ziel ist es, sowohl die Verfolgerperspektive des MfS als auch die Spannungen zwischen staatlicher Ideologie, gesellschaftlichen Wandlungsprozessen und jugendkultureller Praxis sichtbar zu machen. Die Untersuchung zeigt, dass Satanismus in der DDR in der Form vereinzelter jugendkultureller Provokationen, symbolischen Verhaltens oder okkult gerahmter Praktiken existierte, die in den Augen des MfS durch westliche Einflüsse und „negativ-dekadente“ Szenen motiviert erschienen. Die Behörde übernahm dabei teils unreflektiert westliche Bedrohungsnarrative, deutete diese jedoch in ein säkulares, sozialistisch motiviertes Feindbild um. Die Analyse offenbart ein eindrückliches Panorama bürokratischer Unsicherheiten: Die Stasi rang mit diffuser Symbolik, uneindeutigen Szenecodes und der eigenen begrenzten Deutungshoheit. So wird „Satanismus“ weniger als reales Phänomen sichtbar denn als Projektionsfläche eines überforderten Sicherheitsapparates in der Spätphase des Staatssozialismus. Die Arbeit leistet damit einen Beitrag zur Erforschung von Wissensproduktion und -beständen autoritärer Staaten sowie der Rolle sprachlicher Ordnungsmuster in der Konstruktion gesellschaftlicher Devianz