An equivariant surgery classification of CpC_p-surfaces

Let $p$ be an odd prime, and let $C_p$ denote the cyclic group of order $p$. We use equivariant surgery methods to classify all closed, connected $2$-manifolds with an action of $C_p$. We additionally provide a way to construct representatives of each isomorphism class using a series of equivariant surgery operations. The results in this paper serve as an odd prime analogue to a similar classification proved by Dan Dugger

Spectral Data of Avian Plumage

Plumage coloration of museum bird skins provides significant morphometrical data, although it is difficult to objectively access the latter. Among the different methods of analyzing coloration, reflection-spectrophotometry is the most effective means to collect such data, coping with the feather’s property of often reflecting ultraviolet light. Using coincident illumination and reading fibers of a conventional reflection-spectrophotometer, I advise positioning the latter at a perpendicular angle to the surface as measuring geometry dramatically affects the quality of obtained data. This measuring geometry on average provides both, the brightest reflections and the least variability in the resulting data. Plumage coloration of museum bird skins has been evaluated with regard to the reliability of the spectral information. Under appropriate storage conditions, the structural iridescent coloration of hummingbirds can be maintained unaltered for more than a hundred years. In contrast, some specimens are subject to variability in their coloration. Whenever dealing with spectral data, a potential a priory variation in plumage coloration has to be taken into account. Museum specimens exposed to light, dust or insect pests are in danger of alteration to their spectral properties and hence, become unsuitable for spectral analysis, either in the first place or due to acquired color changes. Most disadvantageous are the frequently occurring alterations in the ultraviolet as these remain undetectable to the human eye. However, even in the visible spectrum alterations might elude the observer and, in particular, small reflectance peaks could easily be ignored. Furthermore, at low levels of overall brightness and chroma in both, natural dull feathers or bleached specimens, slight variations in the reflectance spectrum might be entirely annihilated. It is essential to consider this disadvantageous variability in spectral data when analyzing avian coloration, as this variability does not represent actual differences within a population. If only overall brightness is reduced, a sample might still be suitable for taxonomic research as it might contain valuable information concerning hue. As the entire spectral property of a feather may be involved in avian signaling, only unaltered feathers are suitable for analysis, if behavioral or ecological topics are involved. For the first time, the crucial significance of preservation agents for the spectral properties of museum bird skins has been clearly demonstrated. Artificial fluorescence in museum bird skins originated in fluorescent compounds in preservation agents as well as from the remains of body fats due to unsatisfactory preservation techniques. As this affects the results of reflection spectrophotometric measurements, skins must be observed under black light illumination before collecting data. In my study, to my knowledge, the most diversified analysis has been conducted involving the distribution of fluorescence in avian plumage. 181 bird species in 14 families with fluorescent plumage parts have been confirmed and hence, avian fluorescence is far more widespread than it was previously assumed. The ecological reasons cannot yet be ascribed to particular context. Evidence for a dependency of both, light environment and biogeographical region was obtained at species level but could not be perpetuated at family level, suggesting an ecological cause of fluorescence

Controlled landfill stabilization by leachate recycle

Issued as Quarterly progress report no. 1-6, Project no. E-20-67

Leichtlösliche, lichtechte Perylen-Fluoreszenzfarbstoffe

Die Synthese von Perylenfarbstoffen 2 mit terminalen Alkylgruppen wird beschrieben. Langkettige n-Alkylgruppen führen nicht zu einer Erhöhung der Löslichkeit, sondern zu einer Erniedrigung. Cycloalkyl-Reste bewirken ein Minimum an Löslichkeit im Bereich der mittleren Ringe und ein Maximum beim Cyclotetradecyl-Rest (2p). Starke Löslichkeitserhöhungen bewirken sekundäre Alkylreste mit zwei langen Ketten. Von diesen ist der Farbstoff 2v mit zwei 1-Hexylheptyl-Resten mit einer Löslichkeit von über 100 g/l in den meisten Lösungsmitteln, einer Fluoreszenzquantenausbeute von ca. 100% und einer ausgesprochen hohen Lichtechtheit auch für Spezialanwendungen geeignet

Do Tourists Change Their International Travel Plans in Times of Terror?

This study presents the preliminary findings of a broader investigation into the level of concern regarding international travel at times of terrorist attacks. The results indicate that there is not a significantly different pattern in demographic characteristics regarding the level of concern. The preliminary findings reveal a strong association between media searching behavior regarding terrorist attacks and level of concern in international travel. Tourists are selective in their destination choice with a tendency to travel more developed destinations. However, tourists demonstrate that they do not change their trip once destination choice is made even in the case of terrorist attacks. Behavioral resistance differs slightly between the most risky and least risky destination choices. Industry specific accessible research such as this enhances theoretical knowledge about resilient or resistant tourists and informs practitioners about how to formulate strategic responses to disruptions to maintain the level of tourist arrivals

Residents as destination advocates: The role of attraction familiarity on destination image

Purpose – Emphasizing the role of residents as destination advocates, this study investigates the influence of residents’ familiarity with, and, favorability of attractions on destination image. Design/methodology/approach – A mixed methods research strategy was employed using fifteen individual in-depth interviews and a survey questionnaire with a sample of N=364. The study utilizes an attraction familiarity index to classify respondents into four groups based on high, average, and low familiarity and examines the characteristics of each in the relationship between informational familiarity, experiential familiarity, and favorability and destination image. Findings – The study reveals resident perceptions of attractions within the tourism product assembly framework and illustrates the positive relationship between the residents’ level of familiarity with, and favorability of visitor attractions and destination image. Further, the findings also demonstrate the significant role of demographic characteristics such as gender and length of residency in the area. The study findings suggest that temporary residents can function as destination advocates. Research limitations/implications – Employees and students from a prominent northeastern university were sampled, representing local residents and temporary residents respectively. While appropriate and fairly representative of the target market for the research questions in this investigation, more work is required to replicate this study utilizing representative samples across different locations. Practical implications – Evidence from our study indicates the importance of marketing to residents as they serve as destination advocates. In particular, the residents’ familiarity with and favorability of attractions is critical to positive destination image. The research offers insights into the identification of potential segments of residents that require special attention. Originality/value – Limited existing research investigates the role of residents as destination advocates, especially in the context of destinations that lack a primary tourism attraction but have a well-balanced mix of attractions

RO(C3)RO(C_3)-graded Bredon Cohomology and CpC_p-surfaces

Let $p$ be an odd prime, and let $C_p$ denote the cyclic group of order $p$. We use equivariant surgery methods to classify all closed, connected $2$-manifolds with an action of $C_p$. We then use this classification in the case $p=3$ to compute the $RO(C_3)$-graded Bredon cohomology of all $C_3$-surfaces in constant $\underline{\mathbb{Z}/3}$ coefficients as modules over the cohomology of a point. We show that the cohomology of a $C_3$-surface is completely determined by its genus, number of fixed points, and whether or not its underlying surface is orientable

Gauging the Utility of a Learning Target Theory of Action to Address Perceived Obstacles to Teaching and Learning During the COVID-19 Pandemic

This qualitative study was guided by the following research questions: What instructional challenges did teachers face related to designing and delivering lessons remotely during COVID-19? How did those challenges impact teacher perceptions of self-efficacy for providing meaningful lessons for their students? What is the utility of a learning target theory of action for addressing teachers instructional practice challenges and perceptions of self-efficacy? Six participants were selected from a convenience sample and asked to complete a survey with ten open-ended prompts. Their responses were analyzed by individual participant and also across participants through close reading strategies. The analyses revealed six common challenges and seven themes within their responses. The six challenges were analyzed to reveal negative impacts on participant self-efficacy. Those challenges and impacts were further analyzed to test the utility of A Learning Target Theory of Action for aiding educators and educational leaders in overcoming teacher perceived instructional challenges during the COVID-19 pandemic and that have promise for addressing instructional challenges in other teaching environments

Biocompatibility of very small superparamagnetic iron oxide nanoparticles in murine organotypic hippocampal slice cultures and the role of microglia

Abstract: Superparamagnetic iron oxide nanoparticles (SPIO) are applied as contrast media for magnetic resonance imaging (MRI) and treatment of neurologic diseases despite the fact that important information concerning their local interactions is still lacking. Due to their small size, SPIO have great potential for magnetically labeling different cell populations, facilitating their MRI tracking in vivo. Before SPIO are applied, however, their effect on cell viability and tissue homoeostasis should be studied thoroughly. We have previously published data showing how citrate-coated very small superparamagnetic iron oxide particles (VSOP) affect primary microglia and neuron cell cultures as well as neuron-glia cocultures. To extend our knowledge of VSOP interactions on the three-dimensional multicellular level, we further examined the influence of two types of coated VSOP (R1 and R2) on murine organotypic hippocampal slice cultures. Our data show that 1) VSOP can penetrate deep tissue layers, 2) long-term VSOP-R2 treatment alters cell viability within the dentate gyrus, 3) during short-term incubation VSOP-R1 and VSOP-R2 comparably modify hippocampal cell viability, 4) VSOP treatment does not affect cytokine homeostasis, 5) microglial depletion decreases VSOP uptake, and 6) microglial depletion plus VSOP treatment increases hippocampal cell death during short-term incubation. These results are in line with our previous findings in cell coculture experiments regarding microglial protection of neurite branching. Thus, we have not only clarified the interaction between VSOP, slice culture, and microglia to a degree but also demonstrated that our model is a promising approach for screening nanoparticles to exclude potential cytotoxic effects