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Bakgrund Strömmar av brunalgen sargassum har drabbat Karibien i flera år, särskilt påtagligt det senaste decenniet, sedan år 2011. Den överväldiga mängden sargassum har förknippats med klimatförändringar och utsläpp av gödningsmedel i havet. Sargassum har påvisats orsaka negativa hälsoeffekter för människan, bland annat yrsel, illamående, andningssvårigheter och eksem. Syfte Syftet i studien var att utforska hur strömmar av brunalgen sargassumpåverkar invånarnas livsstil och hälsa på ön Guadeloupe, samt vilka strategier som används för att hantera sargassum i praktiken. Metod Som datainsamlingsmetod har tio informanter intervjuats genom semistrukturerade intervjuer. Studiens informanter har bestått av ickestatliga organisationer, verksamheter inom hälso- och sjukvård, samt organisationer inom turism och maritima sektorn. Resultat Resultatet påvisar en ökad mängd oro av hälsoeffekterna kopplade till brunalgen samt ett kunskapsgap då det kommer till hälsoinformation om sargassum. Slutsats Studiens slutsats är att mer information behövs om hälsoeffekterna av sargassum och att hälsolitteracitet bland invånarna bör utvecklas. Även effektivare åtgärder för att göra sig av med brunalgen är nödvändiga. Därtill kan strömmar av sargassum anses vara ett hinder för destinationen att arbeta för Förenta nationernas globala mål nummer tre – god hälsa och välbefinnande, mål tretton – bekämpa klimatförändringarna, samt mål fjorton – hav och marina resurser. / Background Waves of the brown algae sargassum have been floating over the Caribbean for years, but most noticeably during the last decade, since 2011. The overwhelming amount of sargassum has been linked to climate change and the release of fertilisers into the ocean. Sargassum has been shown to cause negative health effects, including dizziness, nausea, breathing difficulties, and eczema. Objective The purpose of the study has been to explore how Guadeloupe is handling the seaweed sargassum, and how inhabitants’ health and lifestyle are affected. Method As a data collection method, ten informants were interviewed through semi-structured interviews. The informants have consisted of nongovernmental organisations, the health care sector and organisations within the tourism and marine sector. Results The results show an increased amount of concern about the health effects linked to the brown algae sargassum and a knowledge gap when it comes to health information about the brown algae. Conclusion The study's conclusion is that more information is needed about the health effects of sargassum, health literacy among the inhabitants requires development, and more effective measures to get rid of brown algae are necessary. In addition, waves of sargassum can be an obstacle for the destination to work for United Nation’s global goals number three -good health and well-being, goal thirteen - climate action, and goal fourteen- life below water.

<p>We use numerical simulations to examine the fragmentation of protostellar discs via gravitational instability (GI), a proposed formation mechanism for gas-giant planets and brown dwarfs. To accurately model heating and cooling, we have implemented radiative transfer (RT) in the TreeSPH code Gasoline, using the flux-limited diffusion approximation coupled to photosphere boundary cooling. We present 3D radiation hydrodynamics simulations of discs that are gravitationally unstable in the inner 40 AU; these discs do not fragment because the cooling times are too long. In prior work, one of these discs was found to fragment; however, we demonstrate that this resulted from an over-estimate of the photosphere cooling rate. Fragmentation via GI does not appear to be a viable formation mechanism in the inner 40 AU.</p> <p>We also present simulations of GI in the outer regions of discs, near 100 AU, where we find GI to be a viable formation mechanism. We give a detailed framework that explains the link between cooling and fragmentation: spiral arms grow on a scale determined by the linear gravitational instability, have a characteristic width determined by the balance of heating and cooling, and fragment if this width is less than twice their Hill radius. This framework is consistent with the fragmentation and initial fragment masses observed in our simulations. We apply the framework to discs modelled with the commonly-used beta-prescription cooling and calculate the critical cooling rate for the first time, with results that are consistent with previous estimates measured from numerical experiments.</p> <p>RT is fundamentally important in the star formation process. Non-ionizing radiation heats the gas and prevents small-scale fragmentation. Ionizing radiation from massive stars is an important feedback mechanism and may disrupt giant molecular clouds. We present methods and tests for our implementation of ionizing radiation, using the Optically-Thin Variable Eddington Tensor method.</p> / Doctor of Philosophy (PhD)

This work examines British inquiry into the human mind in the early nineteenth century using a multivalent structural analysis of ideas and practices within traditions established by Hume, Hartley, and Reid. While these traditions were propagated into the nineteenth century by such figures as Thomas Brown, James Mill, Sir William Hamilton, and Alexander Bain, this later period has received a dearth of attention in the history of psychology, the history of philosophy, and the history of ideas in general. This conspicuous lacuna forms the basis for two simple questions: What was the situated significance of work on the human mind in nineteenth century Britain? What was it supposed to accomplish, or be about? In particular, I focus on the differentiation of science from philosophy as a particular kind of non-science, investigating a set of existing formulations of the respective characters of the two. Using this historiographic survey as a springboard, I establish an analytical apparatus based upon four structural dimensions that I term conceptual, expository, iconic, and genealogical. Taken together, these four elements form an historical problematic, a set of persistent features and issues that structured work on mental subjects. With respect to conceptual structure, I propose a set of a dozen persistently central, but fluid, concept clusters involved in the study of mind. Regarding texts themselves, I situate my subject in terms of specific audience groups, patterns of expository development, and topical scope. I also examine the limiting influence of authorial and editorial practices on the appearance of the conceptual systems these texts convey. Iconic structural patterns focus even more closely on textual content, demonstrating shifts in the density, nature, and extent of citation within the intellectual community. These four dimensions interact significantly, reflecting the complex character of an active community of intellectual discussion. Having established this analytical space, I return to the basic terminological distinction between science and philosophy to investigate what was at stake in distinguishing these two fields in the nineteenth century. The dichotomy was far from definitive: British mental inquiry from the time of Hume's Treatise to that of Bain's first two major works never established a firm division of science from philosophy, but the evidence suggests several directions of tension along which this split would subsequently emerge. As demonstrated by evidence from the first volume of the journal, Mind, founded by Bain in 1876, discussions among students of the human mind in the nineteenth century established a position for mental philosophy itself as arbiter of the new science-philosophy dipole. In this light, the establishment of Mind can be viewed as the creation of a boundary-object that itself constituted this distinction in psychological terms. / Ph. D.

Rhizoctonia blight (sensu lato) is a common and serious disease of many turfgrass species. The most widespread causal agent R. solani consists of several genetically different anastomosis groups (AGs) and subgroups. Though anastomosis or hyphal fusion reactions have been used to group Rhizoctonia species, they are time consuming and sometimes difficult to interpret. Anastomosis reactions are incapable of identifying isolates belonging to different AG subgroups within an AG. This study evaluated molecular techniques in comparison with traditional anastomosis grouping (AG) to identify and group isolates of Rhizoctonia. More than 400 Rhizoctonia isolates were collected from diseased turfgrass leaves from eight geographic areas in Virginia and Maryland. A random sample of 86 isolates was selected and initially characterized by colony morphology, nuclei staining and anastomosis grouping. Molecular identification was performed by analysis of rDNA-ITS region and DNA fingerprinting techniques universally primed PCR (UP-PCR) and amplified fragment length polymorphism (AFLP). The cladistic analysis of ITS sequences and UP-PCR fragments supported seven clusters. Isolates of R. solani AG 1-IB (n=18), AG 2-2IIIB (n=30) and AG 5 (n=1) clustered separately. Waitea circinata var. zeae (n=11), and var. circinata (n=4) grouped separately. A cluster of six isolates (UWC) did not fall into any known Waitea group. Most of the binucleate Rhizoctonia-like fungi (BNR) (n=16) grouped separately. AFLP grouping also largely agreed with the above results. However, UWC isolates clustered into two groups. Molecular analyses corresponded well with traditional anastomosis grouping by clustering isolates within an AG or AG subgroup together. UP-PCR cross-hybridization could distinguish closely related Rhizoctonia isolates to their infraspecies level. Genetically related isolates belonging to the same AG subgroups cross-hybridized strongly, while isolates of different AGs did not cross-hybridize or did so weakly. Sequence-characterized amplified region (SCAR) markers were generated from UP-PCR products to identify isolates of major pathogenic groups AG 1-IB and AG 2-2IIIB. Specific primer pairs successfully distinguished isolates of AG 1-IB and AG 2-2IIIB from isolates of other AGs. Sensitivity of Rhizoctonia species and AGs was tested in vitro to commercial formulations of iprodione, triticonazole and pyraclostrobin. W. circinata isolates were moderately sensitive to iprodione while isolates of R. solani and BNR were extremely sensitive. Isolates of AG 2-2IIIB showed less sensitivity to triticonazole than other Rhizoctonia isolates. W. circinata var. zeae isolates were moderately sensitive to pyraclostrobin while most of the other isolates were extremely sensitive. / Ph. D.

Brown v. Board of Education (1954) was a significant court case fought to provide equal educational opportunities for African-American students. Though the case was fought with good intentions, there may have been unintended consequences that occurred due to the policy implementation. The purpose of this research was to explore the policy, its implementation, and assess the extent to which the goals of the original policy were met. This study used a mixed-methods approach and was set within one large urban school district. The qualitative portion of the study included interviews with a small group of educators who were directly impacted by Brown and its implementation. The data from both the interviews and the selected focus schools indicated that the initial goals of Brown, equal educational opportunities and integrated schooling, were not met. This research provided information from key areas that may serve as a guide to help make future policy implementation successful.

In 2021, 17-year periodical cicadas (Magicicada spp.) in Brood X emerged throughout much of the eastern United States. Due to their abundance and lack of predator avoidance during their short six-week period on the above-ground landscape, many species of animals consume cicadas and in turn have short-term habitat use and population responses. The response of bats to periodical cicadas is largely unknown. Using a before-after-control-impact study design, we deployed ultrasonic acoustic detectors during the summers of 2020–2022 within and just outside the range of the cicada emergence along the Potomac River corridor of Maryland and Virginia. For total bat activity, there was significantly more acoustic activity within the range of the cicada emergence the year during and the year following emergence than where emergence did not occur. Additionally, for all individual species and phonic groups, bat activity increased the year during and year after the emergence within the range of periodical cicadas compared to the year prior to emergence. Our study demonstrates that periodical cicadas may serve as a resource pulse that can cause an increase in bat activity and suggests at least a short-term local to regional population increase from immigration the year during and from recruitment the year following. Bats of the mid-Atlantic have been negatively affected by numerous stressors including white-nose syndrome, wind turbine development, and land use change. One species suffering widespread population decline over the last decade in the mid-Atlantic has been the little brown bat (Myotis lucifugus). Understanding the space use and resource selection of remaining populations is critical for management and species recovery. Nevertheless, there are difficulties with studying the movement of insectivorous bats due to their small size and high vagility. Traditional foraging studies of Myotis spp. have used fixed station telemetry and associated multi-azimuthal observations to estimate the location of individuals. However, single azimuth observations are often unable to be included in these studies leading to more potential location estimates missing from movement models. During the summer of 2022, I radio-tagged little brown bats from a maternity colony along the Potomac River in Maryland and collected bearings on nine individuals using fixed station telemetry from sunset until bats returned to the maternity roost. Location estimates were obtained from both single and multi-azimuthal observations. I fit movement models for each individual and used auto-correlated kernel density estimation (AKDE) to estimate space use. I also assessed second and third order habitat selection of individual bats. The average 95% AKDE for males was 889 ha ± 424.6 and 699.3 ha ± 129 for adult females. I found bats had higher predicted use of habitat that was closer in distance to water and wetlands and further from open habitat at the second order and closer to water and open habitat at the third order of resource selection. Habitat associations were similar to previous little brown bat resource selection studies. However, estimates of space use were larger than those using other movement models. This study was novel in that it incorporated single azimuth observations and periodicity into models of space use, thereby increasing sample size and offering a new framework for future telemetry studies. These estimates of space use can be used by land managers to protect the habitat of this imperiled species. / Master of Science / In 2021, 17-year periodical cicadas (Magicicada spp.) in Brood X emerged throughout much of the eastern United States in high abundance. As an abundant food resource, many animals consume periodical cicadas while they are above ground during the summers. This has allowed for short-term population increases and changes in reproduction in some species. However, the response of bats to periodical cicadas is largely unknown. To study this, I deployed ultrasonic acoustic detectors that recorded six species/species groups of bats during the summers of 2020–2022 within and just outside the range of the cicada emergence along the Potomac River Corridor, Maryland, and Virginia. I observed significantly more total bat acoustic activity within the range of the cicada during the emergence year and the year following than where emergence did not occur. Also, for all individual species and species groups, bat activity increased in the year during and after the emergence within the range of periodical cicadas compared to the year before emergence. My study demonstrates that periodical cicadas cause an increase in bat activity and may suggest a population increase in the areas where the emergence has occurred. Bats of the mid-Atlantic have experienced population declines due to numerous stressors including white-nose syndrome caused by the fungus Pseudogymnoascus destructans, wind turbine development, and habitat fragmentation. One species that has been heavily affected by white-nose syndrome is the little brown bat (Myotis lucifugus). To help conserve the species, understanding their home range and their resource needs is critical. However, little brown bats are small and agile fliers which poses difficulties for tracking them. Traditional foraging studies of species in this genus have used telemetry to obtain triangulations and location estimates of individuals but often leave out data collected from a single bearing as it is difficult to calculate the true location of the animal. During the summer of 2022, I radio-tagged little brown bats from a maternity colony along the Potomac River in Maryland and collected bearings on nine individuals using fixed station telemetry from sunset until bats returned to the maternity roost. We estimated locations from both triangulations and single bearings. I calculated movement models for each individual and fit them to an auto-correlated kernel density estimator (AKDE) of space use. The average 95% auto-correlated kernel density estimates of space use (AKDE) for males was 889 ha ± 424.6 and 699.3 ha ± 129 for adult females. I also assessed the habitat selection of individuals within their home range and across the nearby landscape. I found that bats preferred to use areas closer to water and wetlands and preferred to use areas closer to open habitat within their home range but preferred to use areas further from open habitat across the landscape. Habitat associations were similar to previous little brown bat resource selection studies. However, estimates of space use were larger than those using other movement models. My study was novel in that it incorporated single azimuth observations and periodicity into models of space use, thereby increasing sample size and offering a new framework for future telemetry studies. These estimates of space use can be used by land managers to protect the habitat of this imperiled species.