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Toxizität mobiler Endgeräte
No full textDas toxische Potential mobiler Endgeräte lässt sich bislang nicht eindeutig abschätzen. Es gibt Studien, in denen elektromagnetische Strahlung, wie sie in mobilen Endgeräten verwendet wird, eine karzinogene Wirkung entfalten kann. Gleichzeitig widerlegen andere Studien diesen Befund. Andere toxische Effekte, wie eine fruchtschädigende Wirkung, teratogene Wirkung, thermale Effekte, Schädigungen von Nerven und des Gehörapparates sowie Beeinflussungen des Stoffwechsels, können angesichts der bislang publizierten Ergebnisse nicht bewiesen werden. Dennoch besitzen die Bestandteile dieser Geräte ein toxisches Potential, wenn sie über die Nahrungskette oder die Luft in den Körper gelangen. Vor allem Schwermetalle, Flammenschutzmittel und Weichmacher spielen dabei eine bedeutende Rolle
Alltagsbeeinträchtigungen bei neurokognitiven Störungen: Entwicklung eines differenzierten Erfassungsinstrumentes für Forschung und Praxis
No full textAn internet‐based cognitive behavioural intervention for adults with depression in Arabic‐speaking countries: A randomized controlled trial
No full textNominal ellipsis reveals concord in Moksha Mordvin
No full textOn the basis of original data from Moksha Mordvin (Finno-Ugric), I argue that some languages have nominal concord even though modifiers of the noun generally do not show inflection. Evidence for the presence of concord comes from nominal ellipsis, under which inflection is phonologically realized and restricted in the same way as regular nominal concord. To account for the distribution of concord exponents, I develop a model that allows features to be present in syntax but avoid realization. In particular, I propose that (i) Spellout applies to a node as soon as its Merge and Agree features are satisfied and (ii) Agree features are by default illegible at PF and need to undergo an operation called Probe Conversion in order to become accessible to PF processes. The distribution of features then follows from the relative timing of Spellout and Probe Conversion
Bloch surface wave polaritons in ZnO-based photonic crystals
No full textAs part of this work, exciton-polaritons, which consist of Bloch modes on the sur-
face of one-dimensional photonic crystals and excitons in zinc oxide (ZnO), were
investigated using experimental and numerical methods. A primary focus was directed toward the propagation length of Bloch polaritons (BP), as they are based on
guided waves and therefore allow for long-range propagation, which is useful for the
development of functional integrated polariton applications. Due to the high binding energy of excitons in ZnO, at 60 meV, Bloch polaritons are stable beyond room
temperature. The dispersion of the strongly interacting polaritons was observed in
experiments up to 430K. For the detection of the particles at high temperatures, the
coupling strength of the energy splitting was determined. The increased roughness
of ZnO in (amorphous) heterostructures leads to a reduction in polariton lifetime.
Therefore, the smoothing of ZnO thin films using an argon ion beam and the consequences of this process for the optical and structural properties were investigated,
which allows for the optimization of the ratio between roughness, material removal,
and oscillator strength of (excitonic) dipole transitions by adjusting the irradiation
time. Since the photonic surface modes correspond to evanescent waves, the coupling to vacuum modes in planar systems requires a structuring of the surface with
diffraction gratings having lattice constants smaller than 1 μm. For such structures,
the spectral response was characterized using spectroscopic ellipsometry, taking into
account the spectral bandwidth of the monochromator slit, and an excitation of surface waves was demonstrated. Additionally, in this work, the emission of propagating
Bloch polaritons was measured, and their propagation length, resolved spectrally,
was determined. The exponential decay of the intensity yielded propagation lengths
of up to 100, μm for polaritons with a high photonic fraction of approximately 90 %.
Due to the extension of the electromagnetic mode across the entire dielectric multilayer, the propagation length for all wavelengths was greater than that for wave
propagation in pure ZnO, which is limited by the inverse absorption coefficient.:1 Introduction 1
2 Basics of Cumulative Part 7
2.1 Physical background and concepts . . . . . . . . . . . . . . . . . . . . 8
2.1.1 Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.1.2 Optics in layered media . . . . . . . . . . . . . . . . . . . . . 12
2.1.3 Bloch surface wave polaritons . . . . . . . . . . . . . . . . . . 24
2.2 Experimental and computational techniques . . . . . . . . . . . . . . 29
2.2.1 Sample preparation . . . . . . . . . . . . . . . . . . . . . . . . 29
2.2.2 Structural characterization . . . . . . . . . . . . . . . . . . . . 34
2.2.3 Optical spectroscopy . . . . . . . . . . . . . . . . . . . . . . . 36
2.2.4 Rigorous coupled-wave analysis . . . . . . . . . . . . . . . . . 41
3 Cumulative Part 49
[C1] Strong coupling of Bloch surface waves and excitons in ZnO up to 430 K 50
[C2] Optical and structural characterization of zinc oxide thin films upon ion beam assisted smoothing . . . . . . . . . . . . . . . . . . . . . . . 61
[C3] Characterization of dielectric diffraction gratings on multilayer structures by spectroscopic ellipsometry . . . . . . . . . . . . . . . . . . . 70
[C4] Long-range propagation of Bloch surface wave polaritons . . . . . . . 80
4 Summary and Outlook 89
Appendix 93
4.1 Bloch surface wave polaritons for IBS-treated ZnO . . . . . . . . . . . 93
4.2 RCWA matrix formulation . . . . . . . . . . . . . . . . . . . . . . . . 107
Bibliography 115
Publications and author contributions 133
Abbreviations 137
Acknowledgements 139
Selbstst¨andigkeitserkl¨arung nach §10 141
Zusammenfassung nach §11 143Im Rahmen dieser Arbeit wurden Exziton-Polaritonen, welche aus Bloch-Moden
an der Oberfläche von eindimensionalen photonischen Kristallen und Exzitonen
in Zinkoxid (ZnO) bestehen, anhand experimenteller und numerischer Methoden
untersucht. Dabei war insbesondere die Propagationslänge der Bloch-Polaritonen
(BP) von Interesse, da diese auf geführten Wellen basieren und daher eine weitreichende Propagation erlauben, was für die Entwicklung funktionaler integrierter
Polariton-Anwendungen nützlich ist. Auf Grund der hohen Bindungsenergie von
Exzitonen in ZnO mit 60 meV, sind Bloch-Polaritonen über Raumtemperatur hinaus stabil. Die Dispersion der stark wechselwirkenden Polaritonen konnte in Experimenten bis 430 K observiert werden. Für den Nachweis der Teilchen bei hohen Temperaturen wurde die Kopplungsstärke der Energieaufspaltung besimmt. Auf Grund der erhöhten Rauheit von Zinkoxid in (amorphen) Heterostrukturen, kommt es zu einer Reduktion der Lebensdauer der Polaritonen. Daher wurde die Glättung von ZnO-Dünnfilmen mittels eines Argon-Ionenstrahls sowie die Folgen für die optischen und strukturellen Eigenschaften untersucht, was die Optimierung des Verhältnisses zwischen Rauheit, Materialabtrag und Oszillatorstärke von (exzitonischen) Dipolübergängen, durch die Anpassung der Bestrahlungszeit, erlaubt. Da die photonischen Oberflächenmoden evaneszenten Wellen entsprechen, bedarf es für die Kopplung an die Vakuum-Moden in planaren Systemen einer Strukturierung der Oberfläche mit Beugungsgittern, mit Gitterkonstanten kleiner 1 μm, notwendig. Für solche Strukturen wurde die spektrale Antwort mittels spektroskopischer Ellipsometrie, unter Berücksichtigung der spektralen Bandbreite des Monochromator-Spalts, charakterisiert und eine Anregung von Oberflächenwellen nachgewiesen. Außerdem wurde in dieser Arbeit die Emission propagierender Bloch-Polaritonen gemessen und deren spektral aufgelöste Propagationslänge bestimmt. Der exponentielle Abfall der Intensität ergab Propagationslängen von bis zu 100 μm für Polaritonen mit hohem
photonischen Anteil von ca. 90 %. Aufgrund der Ausdehnung der elektromagnetischen Mode über die gesamte dielektrische Multischicht, lag die Proagationslänge
für alle Wellenlängen oberhalb jener für Wellenausbreitung in reinem ZnO, welche
durch den inversen Absorptionskoeffizienten limitiert ist.:1 Introduction 1
2 Basics of Cumulative Part 7
2.1 Physical background and concepts . . . . . . . . . . . . . . . . . . . . 8
2.1.1 Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.1.2 Optics in layered media . . . . . . . . . . . . . . . . . . . . . 12
2.1.3 Bloch surface wave polaritons . . . . . . . . . . . . . . . . . . 24
2.2 Experimental and computational techniques . . . . . . . . . . . . . . 29
2.2.1 Sample preparation . . . . . . . . . . . . . . . . . . . . . . . . 29
2.2.2 Structural characterization . . . . . . . . . . . . . . . . . . . . 34
2.2.3 Optical spectroscopy . . . . . . . . . . . . . . . . . . . . . . . 36
2.2.4 Rigorous coupled-wave analysis . . . . . . . . . . . . . . . . . 41
3 Cumulative Part 49
[C1] Strong coupling of Bloch surface waves and excitons in ZnO up to 430 K 50
[C2] Optical and structural characterization of zinc oxide thin films upon ion beam assisted smoothing . . . . . . . . . . . . . . . . . . . . . . . 61
[C3] Characterization of dielectric diffraction gratings on multilayer structures by spectroscopic ellipsometry . . . . . . . . . . . . . . . . . . . 70
[C4] Long-range propagation of Bloch surface wave polaritons . . . . . . . 80
4 Summary and Outlook 89
Appendix 93
4.1 Bloch surface wave polaritons for IBS-treated ZnO . . . . . . . . . . . 93
4.2 RCWA matrix formulation . . . . . . . . . . . . . . . . . . . . . . . . 107
Bibliography 115
Publications and author contributions 133
Abbreviations 137
Acknowledgements 139
Selbstst¨andigkeitserkl¨arung nach §10 141
Zusammenfassung nach §11 14
No Harmful Effect of Endovascular Treatment before Decompressive Surgery: Implications for Handling Patients with Space-Occupying Brain Infarction
No full textThis study explored short- and mid-term functional outcomes in patients undergoing decompressive hemicraniectomy (DHC) due to space-occupying cerebral infarction and asked whether there is a potentially harmful effect of a priorly performed endovascular treatment (EVT). Medical records were screened for patients requiring DHC due to space-occupying cerebral infarction between January 2016 and July 2021. Functional outcomes at hospital discharge and at 3 months were assessed by the modified Rankin Scale (mRS). Out of 65 patients with DHC, 39 underwent EVT before DHC. Both groups, i.e., EVT + DHC and DHC alone, had similar volumes (280 ± 90 mL vs. 269 ± 73 mL, t-test, p = 0.633) and proportions of edema and infarction (22.1 ± 6.5% vs. 22.1 ± 6.1%, t-test, p = 0.989) before the surgical intervention. Patients undergoing EVT + DHC tended to have a better functional outcome at hospital discharge compared to DHC alone (mRS 4.8 ± 0.8 vs. 5.2 ± 0.7, Mann–Whitney-U, p = 0.061), while the functional outcome after 3 months was similar (mRS 4.6 ± 1.1 vs. 4.8 ± 0.9, Mann–Whitney-U, p = 0.352). In patients initially presenting with a relevant infarct demarcation (Alberta Stroke Program Early CT Score ≤ 5), the outcome was similar at hospital discharge and after 3 months between patients with EVT + DHC and DHC alone. This study provided no evidence for a harmful effect of EVT before DHC in patients with space-occupying brain infarction
A Single Dose of Piperacillin Plus Tazobactam Gel as an Adjunct to Professional Mechanical Plaque Removal (PMPR) in Patients with Peri-Implant Mucositis: A 6-Month Double-Blind Randomized Clinical Trial
No full textObjectives: This randomized, placebo-controlled, double-masked clinical trial aimed to evaluate the clinical and microbiological efficacy of professional mechanical plaque removal (PMPR) with or without adjunctive application of piperacillin plus tazobactam gel in the treatment of peri-implant mucositis (PiM) for up to 6 months. Materials and Methods: The study included 31 patients with peri-implant mucositis (bleeding on probing (BoP) > 1 at at least one site at baseline, absence of peri-implant bone loss compared with a previous radiograph). After randomized assignment to test and control groups, patients received full-mouth supragingival scaling with or without piperacillin plus tazobactam gel. Clinical examination was performed at baseline and after 3 and 6 months, and a microbiological examination was performed at baseline and after 3 months. Results: After six months, both treatment modalities resulted in significant reductions and improvements in clinical parameters at the implant sites. Neither study group achieved a complete resolution of PiM (i.e., BoP ≤ 1 per implant). The number of implants with BoP decreased statistically significantly between subsequent time points (p < 0.001) in both the test and the control group. Significant BoP differences (p = 0.039) were observed between groups at 6 months (difference to baseline) following therapy. Conclusions: Within the limitations of the present study, the single use of a slow-release, locally applied antibiotic combination of piperacillin and tazobactam gel, adjunctive to PMPR, showed an improvement in clinical variable of implants diagnosed with PiM. The adjunctive treatment resulted in higher BoP reduction when compared to the control, but no significant differences were observed regarding the changes in other clinical and microbiological parameters
Causal inference for psychologists who think that causal inference is not for them
No full textCorrelation does not imply causation and psychologists' causal inference training often focuses on the conclusion that therefore experiments are needed—without much consideration for the causal inference frameworks used elsewhere. This leaves researchers ill-equipped to solve inferential problems that they encounter in their work, leading to mistaken conclusions and incoherent statistical analyses. For a more systematic approach to causal inference, this article provides brief introductions to the potential outcomes framework—the “lingua franca” of causal inference—and to directed acyclic graphs, a graphical notation that makes it easier to systematically reason about complex causal situations. I then discuss two issues that may be of interest to researchers in social and personality psychology who think that formalized causal inference is of little relevance to their work. First, posttreatment bias: In various common scenarios (noncompliance, mediation analysis, missing data), researchers may analyze data from experimental studies in a manner that results in internally invalid conclusions, despite randomization. Second, tests of incremental validity: Routine practices in personality psychology suggest that they may be conducted for at least two different reasons (to demonstrate the non-redundancy of new scales, to support causal conclusions) without being particularly suited for either purpose. Taking causal inference seriously is challenging; it reveals assumptions that may make many uncomfortable. However, ultimately it is a necessary step to ensure the validity of psychological research
Explaining variation in plant-herbivore associational effects in a tree biodiversity experiment
No full text1. Within biodiversity-ecosystem function research, a major outstanding question is
how herbivory, a critical ecosystem function at the base of the food web, changes
along gradients of plant biodiversity.
2. Neighbourhood-level associational effects are hypothesised to be a strong driver
of biodiversity-herbivory relationships, but we lack a successful framework that
explains the wide variation observed in the sign and magnitude of plant-herbivore
associational effects.
3. In this study, we combine measurements from a tree biodiversity field experiment
with simulation to provide a framework for explaining variation in plant-herbi-
vore associational effects, particularly when herbivores that feed on many dif-
ferent species (e.g. generalists) cause most damage. We show that monoculture
herbivory levels of focal species and their neighbours predict the direction and
strength of associational effects. We provide evidence that this may be due to a
“spillover effect”, in which some insect herbivores attracted to focal individuals
ultimately end up feeding on neighbouring individuals.
4. With an empirically parameterised simulation, we explain how spatial organisa-
tion modifies biodiversity-ecosystem function relationships when associational
effects operate. We suggest a set of experiments to test the generality of our
conceptual framework, to elucidate the underlying mechanisms that produce the
patterns we find, and to ultimately increase the predictability of plant-herbivore
associational effects. We conclude by discussing how our results might inform
pest management in diversified agroecosystems and reforestation sites.
5. Synthesis. Our results provide a potential framework for explaining why positive
and negative plant-herbivore associational effects are often balanced in systems
with primarily generalist herbivores and point to a path forward for predicting when increased plant biodiversity will be associated with increased, decreased or
unchanged levels of insect herbivory on individual plant species in such systems