University of Kaiserslautern
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Similarity of stream insect trait profiles across biogeographic regions
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Habitat templet theory predicts that the functional niches of species evolved in response to selection pressures imposed by each species' spatial–temporal environment. Consequently, similar environmental conditions should lead to convergence in the biological trait composition of biogeographically independent assemblages. Given their high diversity and ubiquitous occurrence, stream insects represent an ideal group to test convergence. Such an analysis should provide insight into both how spatially variable stream insect traits are and how transferable trait–environment relationships are across large spatial scales. We tested two hypotheses: (1) functional niches of stream insects are similar across Australia, Europe, North America, New Zealand and Southern Africa, and (2) the variability in trait profiles of stream insects is positively related to climatic variability within regions.
Location
Australia, Europe, North America, New Zealand and Southern Africa.
Methods
We used trait datasets from each region to compare functional niches and to delineate groups of insects with similar trait profiles (hereafter, trait profile groups or TPGs) in each region. We identified the traits most important in separating TPGs. Finally, we assessed if trait profile variability between TPGs was associated with climatic variability within each region.
Results
We found that functional niches of families largely overlapped across the regions examined, except for partial deviations of some Australian families, but that only two trait combinations characterized TPGs across all regions. Feeding mode and respiration traits consistently drove the separation of families into TPGs. The variability of trait profiles slightly increased with increasing climatic variability.
Main Conclusions
Although our study did not allow to demonstrate mechanisms, it is the first to show large similarities between stream insect functional niches across different biogeographic regions, which might be an indication of their convergence. An important factor shaping stream insect assemblages over these large scales might be climate, indicated by the higher trait profile variation in regions with more diverse climates
Development and Assembly of a Full-Field Optical Coherence Tomography System (TD-FF-OCT) for Technical Applications
Get PDFDie optische Kohärenztomographie (OCT) ist ein relativ junges bildgebendes Verfahren, das sich zu einem etablierten Standard in der Ophthalmologie entwickelt hat und zunehmend auch in technischen Anwendungen eingesetzt wird. Grundlage ist die Interferometrie, die das Prinzip der Überlagerung von Lichtwellen basierend auf der Wellennatur des Lichts zur hochgenauen Messung nutzt. Die OCT ist darauf ausgelegt, mehrere Grenzschichten einer Probe interferometrisch zu erfassen, um eine volumetrische Bildgebung zu ermöglichen. Am Lehrstuhl für Messtechnik und Sensorik (mt&s) der Rheinland-Pfälzisch Technischen Universität Kaiserslautern-Landau wird mit selbstgebauten Weißlichtinterferometern auf dem Gebiet der Oberflächenmesstechnik geforscht. Aufbauend auf den Erkenntnissen dieser Forschung soll im Rahmen dieser Arbeit ein flächenhaft messender optischer Kohärenztomograph im Zeitbereich (TD-FF-OCT) entwickelt werden, der neben der Erfassung der Oberfläche auch eine volumetrische Bildgebung ermöglicht.
Dazu werden zunächst die Grundlagen der Interferometrie und die Signalentstehung erklärt. Darauf aufbauend werden verschiedene Möglichkeiten zur Realisierung eines TD-FF-OCT-Aufbaus erläutert und bewertet. Das Systemdesign wird entworfen und die Komponenten für den Aufbau werden aufgeführt. Nach Inbetriebnahme des Aufbaus wird dieser spezifiziert. Im weiteren Verlauf werden zwei technische Anwendungsfälle aufgezeigt und diskutiert. Zunächst zur Schichtdickenmessung im Rahmen eines industriell motivierten Anwendungsfalles und anschließend im Kontext eines wissenschaftlich motivierten Anwendungsfalles zur volumetrischen Erfassung von Tropfen beim Kondensationsprozess.Optical coherence tomography (OCT) is a relatively new imaging technique that has become an established standard in ophthalmology and is increasingly being used in technical applications. It is based on interferometry, which utilises the principle of superimposing light waves based on the wave nature of light for high-precision measurement. OCT is designed to capture several boundary layers of a sample interferometrically in order to enable volumetric imaging. The Institute for Measurement and Sensor Technology (mt&s) at the Rheinland-Pfälzisch Technische Universität Kaiserslautern-Landau conducts research in the field of surface metrology using self-built white light interferometers. Based on the findings of this research, a Time-Domain Full-Field OCT (TD-FF-OCT) is to be developed as part of this work that enables volumetric imaging in addition to surface detection.
Firstly, the basics of interferometry and signal generation are explained. Based on this, various options for realising a TD-FF-OCT setup are shown and evaluated. The system design is outlined and the components for the setup are listed. Once the setup has been initialised, it is specified. Two technical applications are then presented and discussed. Firstly for coating thickness measurement in the context of an industrially motivated application and then in the context of a scientifically motivated application for the volumetric measurement of droplets in the condensation process
Predictors of expectant fathers’ parental leave-taking intentions before birth: masculinity, fatherhood beliefs, and social support
Get PDFDespite continuing progress, men remain underrepresented in childcare, domestic labor, and other care work. Because parental leave is discussed as a gateway to increasing men’s childcare engagement, we aimed to gain insights into predictors of men’s parental leave-taking intentions during the transition to parenthood. Using outcomes on a continuum from behavioral preferences to more behavior-oriented measures, we examine how masculinity and fatherhood beliefs as well as social support become relevant during men’s formation of their leave-taking intentions. Planned analyses of data collected from 143 expectant fathers in Belgium and Germany revealed that the support men perceive from their partners for taking leave predicts their parental leave-taking desire, intention, and planned length of leave. Moreover, men’s conception of a prototypical man, especially in terms of agency, was linked to their desire to take leave. Against expectations, father role attitudes and workplace support did not emerge as relevant predictors of men’s intended leave-taking. Results of exploratory analyses suggest that care engagement of peers, expected backlash, and self-efficacy beliefs additionally play a role in men’s intended leave-taking. We discuss parental leave as a negotiation process within couples and review the role of men’s normative environment for their intended leave-taking
Zur Beziehung zwischen Konstruktion und Illokution in Schriftäußerungen auf Schildern im öffentlichen Raum Ergebnisse einer Korpusstudie und Implikationen für den schulischen Deutschunterricht
Get PDFSchriftäußerungen auf Hinweis-, Warn- und Verbotsschildern im öffentlichen Raum zeichnen sich durch eine große Vielfalt an sprachlichen Konstruktionen aus, wobei ein beträchtlicher Anteil den „randgrammatischen Phänomenen“ (Fries 1987) zugeordnet werden kann. Auf der Grundlage einer empirischen Korpusstudie wird im Beitrag einerseits der Frage nachgegangen, welche Konstruktions- und Illokutionstypen auf Schildern im öffentlichen Raum zu finden sind. Andererseits wird unter Einbezug projektionistischer und konstruktionistischer Ansätze untersucht, wie die Beziehung von Konstruktion und Illokution in diesem Diskursbereich modelliert werden kann. Auf Basis der Ergebnisse werden Implikationen für den Deutschunterricht in der Sekundarstufe II entwickelt, die eine integrierte Betrachtung von Sprachsystem und Sprachhandeln anstreben
Development of the Annual Spectral Matrix Simulation Method and Assessment of the Effect of Spectral Discretization on Annual Lighting Energy Demand
Get PDFAs suggested by recent findings, light affects humans non-visually by impacting alertness, cognitive performance and various physiological responses. While the research about nonvisual photoreception is still ongoing, architects and designers have begun to conceive ways of integrating provisional recommendations into lighting design practices to enable healthy lighting in living and working spaces. Consequently, there has been a growing demand for annual lighting simulation tools that consider spectral properties of light for prediction and decision-making purposes.
This thesis presents the annual spectral matrix simulation (ASMS) method. ASMS is based on integrating a precomputed annual spectral sky profile into the daylight coefficient approach to predict the spectral distribution of daylight. ASMS serves as the basis for evaluating annual lighting energy demand using spectral simulation of electric light. ASMS and point-in-time simulation with three-, nine-, 27- and 81-channel discretization are presented and discussed. The main aim is to examine the extent of increased accuracy of illuminance and annual lighting energy demand predictions that finer spectral discretization provides in comparison to the simulations with low spectral resolution. This investigation considers photopic as well as melanopic daylight equivalent illuminance.
Finer discretization was found to be particularly beneficial for light sources with discontinuous spectral power distribution. When simulating a prototypical office room with fluorescent luminaires, annual lighting energy demand was underpredicted by 32.2 % or 16.9 kWh/m²a in a three-channel simulation in comparison to finer discretization with 81 channels. For LED luminaires with relatively continuous spectra, the difference ranged between 2.1 % and 7.8 % or 0.2 kWh/m²a and 0.7 kWh/m²a.
As of today, the provision of an adequate level of melanopic equivalent daylight illuminance indoors is not required. The assessment showed that annual lighting energy demand was significantly lower when only photopic illuminance was regarded, but the minimum threshold of melanopic equivalent daylight illuminance was not met for most of the occupied hours. This finding highlights that additional consideration of melanopic equivalent daylight illuminance will lead to higher lighting energy demand. For the implementation of spectrum-based metrics in building and lighting design, high-resolution spectral simulation is therefore highly recommended
The polarizing content warning: how the media can reduce affective polarization
Get PDFPast research suggests that journalists can (unintentionally) exacerbate affective polarization when reporting on growing levels of polarization in society. However, is there a way for journalists to report on the realities of growing political polarization without dividing people further? In our research with five pre-registered experimental studies (N 1⁄4 3,414), we develop the polarizing content warning which, based on inoculation the- ory, warns readers that scientific research suggests reading news content about political polarization may drive further affective polarization. Results indicate that the polarizing content warning can be used both with online news articles and on social media sites, and is able to indirectly reduce affective polarization of readers. Additionally, the polarizing content warning is beneficial both when presented alongside news content and beforehand, and reduces readers’ perceptions of societal polarization, in turn reducing affective polarization. This warning allows journalists to report on societal polarization without further dividing people
Exploring Bilingual Adaptation to Structural Innovations
Get PDFBilinguals have been shown to adapt to syntactic innovations (i.e., structures that deviate
from the standard grammar) either by producing such structures more or by processing them faster
after repeated exposure. However, research on whether they adapt by increasing their acceptability
ratings for innovations is limited. We consider this to be a crucial gap in the literature, since it could
provide insights into how speakers adapt their perception for innovations that they might otherwise
not adapt to in their production and/or processing. On this basis, the present study investigates
overall acceptability and trial-by-trial acceptability (adaptation) for different types of innovations in
Canadian French with grammatical structural equivalents in English. Structure type and individual
differences in language experience (dominance, proficiency, exposure, etc.) are considered as factors
that influence these processes, as previous research has shown that they play a role in the acceptability
of innovations in bilinguals. For this purpose, we employed a timed acceptability judgment task
(TAJT), where adult bilingual speakers of French and English in Canada were asked to rate innovative
sentences in French and their standard (grammatical) counterparts as fast and spontaneously as
possible. Both acceptability ratings (offline measure) and response times (RTs) (online measure) across
trials were measured to test whether speakers show adaptation on both levels. Results revealed that
innovations were rated lower and for most structure types slower than their standard counterparts,
with the different types of innovations showing differences. Crucially, adaptation on a group level
was reflected only in response times and not in acceptability ratings. On an individual level, though,
some participants adapted their ratings, but not consistently across all innovation types. Moreover,
ratings and RTs were influenced by individual language experience, with participants with a higher
contact with French (higher French Score) being faster and less accepting of innovative sentences
compared to participants with a lower contact with French
A local-global principle for unipotent characters
Get PDFWe obtain an adaptation of Dade's Conjecture and Späth's Character Triple Conjecture to unipotent characters of simple, simply connected finite reductive groups of type A, B and C. In particular, this gives a precise formula for counting the number of unipotent characters of each defect d in any Brauer l-block B in terms of local invariants associated to e-local structures. This provides a geometric version of the local-global principle in representation theory of finite groups. A key ingredient in our proof is the construction of certain parametrisations of unipotent generalised Harish-Chandra series that are compatible with isomorphisms of character triples
An atomistic study of sticking, bouncing, and aggregate destruction in collisions of grains with small aggregates
Get PDFMolecular dynamics simulations are used to study central collisions between spherical grains and between grains and small grain aggregates (up to 5 grains). For a model material (Lennard-Jones), grain–grain collisions are sticking when the relative velocity v is smaller than the so-called bouncing velocity and bouncing for higher velocities. We find a similar behavior for grain–aggregate collisions. The value of the bouncing velocity depends only negligibly on the aggregate size. However, it is by 35% larger than the separation velocity needed to break a contact; this is explained by energy dissipation processes during the collision. The separation velocity follows the predictions of the macroscopic Johnson–Kendall–Roberts theory of contacts. At even higher collision velocities, the aggregate is destroyed, first by the loss of a monomer grain and then by total disruption. In contrast to theoretical considerations, we do not find a proportionality of the collision energy needed for destruction and the number of bonds to be broken. Our study thus sheds novel light on the foundations of granular mechanics, namely the energy needed to separate two grains, the difference between grain–grain and grain–aggregate collisions, and the energy needed for aggregate destruction
Permaculture enhances carbon stocks, soil quality and biodiversity in Central Europe
Get PDFPermaculture is proposed as a tool to design and manage agroecological systems in response to the pressing environmental challenges of soil degradation, climate change and biodiversity loss. However, scientific evidence on the effects of permaculture is still scarce. In this comprehensive study on a wide range of soil and biodiversity indicators, we examined nine farms utilizing permaculture and paired control fields with locally predominant agriculture in Central Europe. We found 27% higher soil carbon stocks on permaculture sites than on control fields, while soil bulk density was 20% lower and earthworm abundance was 201% higher. Moreover, concentrations of various soil macro- and micronutrients were higher on permaculture sites indicating better conditions for crop production. Species richness of vascular plants, earthworms and birds was 457%, 77% and 197% higher on permaculture sites, respectively. Our results suggest permaculture as effective tool for the redesign of farming systems towards environmental sustainability