Ranking the components of ecological resistance to biological invaders : an experimental manipulation in a southern Appalachian riparian forest.

The theory that communities can withStand introductions of non-natives is called “ecological resistance,” which was hypothesized to consist of three interdependent elements: (1) environmental resistance, which may be mediated through natural disturbances; (2) biotic resistance, which is a consequence of plant adaptive strategies; and (3) demographic resistance, which may be expressed as differential dispersal and establishment. I separated the influences of natural disturbance, biotic resistance, and demographic resistance and ranked their contributions to ecological resistance with a field experiment. This research was conducted at Big Stony Creek, a naturally flooded system within the Jefferson National Forest in southwestern Virginia. I manipulated resident diversities and functional group representation along a disturbance gradient and planted differing quantities of invaders into these manipulated plots. Success of an invasion was measured by survivorship and growth of the invader

Active Galactic Nuclei and the Correlated Properties of Neighboring Galaxies

When a galaxy's central supermassive black hole is actively accreting matter, it becomes an active galactic nucleus (AGN). AGN are most commonly found in the "green valley", a region of relatively low density on a color/magnitude diagram of galaxies located between the denser red and blue sequences. I performed an analysis on a sample of galaxies collected from the Sloan Digital Sky Survey (SDSS) database in search of the properties possessed by a target galaxy's neighboring galaxies that correlate with the probability of finding an AGN in that target. I found that, among galaxies with AGN, galaxies with more neighbors – galaxies within a projected distance of 0.5 megaparsecs (Mpc) – tend to be redder than galaxies with few neighbors for the majority of the color range in my sample; however, among galaxies without AGN, this trend only exists outside of the green valley. Additionally, I found that galaxies with fewer neighbors are more likely to contain AGN than galaxies with many neighbors.No embargoAcademic Major: Astronomy and Astrophysic

Infant growth trajectories and lipid levels in adolescence

Developmental Origins of Health and Disease theory posits that elements of early life affect susceptibility to chronic disease during adulthood. Postnatal growth is one such element of early life that has been hypothesized as influencing chronic disease such as Atherosclerotic Cardiovascular Disease (ASCVD), which is responsible for one out of every three deaths in the United States. Researchers in the field of developmental origins hypothesize that postnatal growth is an environmental factor that permanently programs lipid metabolism, a known and well-established risk factor for ASCVD. We investigated the association between early postnatal anthropometric change and adverse lipid levels in adolescence in a contemporary Chilean birth cohort. Primary aims included: a) characterize predictors of infant growth, b) investigate the association between early infant growth trajectories and lipid levels, and c) evaluate the capacity of postnatal growth trajectories to modify the association between functional genetic variants and lipid levels in adolescence. Results from this research demonstrated distinct patterns of growth in which faster anthropometric growth groups were associated with a more favorable lipid profile. In the first manuscript, lower socioeconomic position was associated with a lower length velocity SITAR parameter (-0.22, 95\% CI=-0.31,-0.13). In the second manuscript, the length velocity SITAR parameter was positively associated with HDL-C levels in adolescence (11.5, SE=4.0) indicating higher HDL-C levels with faster length growth. Second, latent growth mixture models supported the strongest associations between higher LDL-C and slower WFL growth although no associations were statistically significant after adjustment for multiple comparisons. Lastly, the third manuscript provided little evidence supporting a concept that growth is an effect modifier when assessing genetic associations with lipids. Taken together, these results identify faster growth in early infancy as a protective factor. Mechanisms by which this occurs remain an open question, and postnatal growth remains a possible environmental cue for lipid metabolism programming. In turn, this information can support the search for optimal postnatal growth and with it, the potential for modification of chronic disease risk factor development later in life.Doctor of Philosoph

Assessing Invasive Alien Species Across Multiple Spatial Scales: Working Globally and Locally

Quantitative investigations on invasive alien species (IAS) across multiple spatial scales are needed because biological invasions often encompass enormous expanses in both donor and invaded ranges and because the immigrants may be carried great distances between these ranges. Although invasion biology is rich in anecdotes, translation of this information into generalizations remains limited by technical shortcomings in data acquisition, inconsistent data assembly, and the continuing search for meaningful indices of the impact of IAS. Much better justification of and greater opportunities to combat IAS could be achieved by distilling all information for IAS into spatially explicit case histories and synthetic predictions on the epidemiology and consequences of biological invasions for public review, discussion, and action. Las investigaciones cuantitativas sobre las especies exóticas invasoras (EEI) a través de numerosas escalas espaciales son necesarias porque las invasiones biológicas abarcan a menudo enormes extensiones, tanto en las áreas de distribución originales como en las áreas invadidas, y porque estos inmigrantes pueden ser transportados a través de grandes distancias entre estas áreas. Aunque la biología de las invasiones es rica en anécdotas, la conversión de esta información en generalizaciones todavía está limitada por deficiencias técnicas en la adquisición de los datos, inconsistencias en el ensamblaje de los datos, y la búsqueda continua de índices significativos del impacto de las EEI. Se podría alcanzar una mejor justificación y mejores oportunidades de combatir a las EEI destilando toda la información de las EEI en estudios de caso espacialmente explícitos y predicciones sintéticas sobre la epidemiología y las consecuencias de las invasiones biológicas para la revisión pública, la discusión y la acción

Saving camels from straws: how propagule pressure-based prevention policies can reduce the risk of biological invasion

Nonnative species that harm or have the potential to cause harm to the environment, economy, or human health are known as invasive species. Propagule pressure may be the most important factor in establishment success of nonnative species of various taxa in a variety of ecosystems worldwide, and strong evidence is emerging that propagule pressure determines both the scale of invasion extent and impact. In a limited way, the US government is applying a “propagule pressure approach” in a variety of prevention policy contexts aimed at minimizing the impact of harmful organisms. However, there are also readily apparent opportunities for enacting propagule pressure-based measures to fill current gaps in invasive species prevention and control at national, state, and local levels. An explicit focus on propagule pressure-based policies could substantially increase the effectiveness of US efforts to prevent the introduction of invasive species through by intentional and unintentional introductions

Temperature measurements of shocked translucent materials by time-resolved infrared radiometry

Infrared emission in the range 2 to 5.5 ..mu..m has been used to measure temperatures in shock-compressed states of nitromethane, cyclohexane and benzene and in polycrystalline KBr. Polymethylmethacrylate shows anomolous emission probably associated with some heterogeneity

Developmental Trajectories of Postpartum Weight 3 Years After Birth: Norwegian Mother and Child Cohort Study

This study explored the developmental trajectories of postpartum weight from 0.5 to 3 years after childbirth, and aimed to determine the associations between postpartum weight trajectories and prepregnancy body mass index and adequacy of gestational weight gain (GWG). Data from the Norwegian Mother and Child Cohort study were used, following 49,528 mothers 0.5, 1.5, and 3 years after childbirth. Analyses were performed using latent growth mixture modeling. Three groups of developmental trajectories of postpartum weight were found, with most women (85.9 %) having a low level of weight retention initially and slight gain over 3 years, whereas 5.6 % of women started at a high postpartum weight retention (on average 7.56 kg) at 0.5 years but followed by a marked weight loss over time (2.63 kg per year on average), and the third trajectory represented women (8.5 %) who had high weight retention high initially (on average 4.67 kg at 0.5 years) and increasing weight over time (1.43 kg per year on average). Prepregnancy overweight and obesity and excessive GWG significantly predicted a high postpartum weight trend. Women had substantial variability in postpartum weight development—both initially after birth and in their weight trajectories over time. Early preventive interventions may be designed to assist women with prepregnancy overweight and obesity and excessive GWG, which helps to reduce the increasing trend for postpartum weight

Investigation of the Effects of Sea Level Rise on Sea Turtle, Shorebird, Seabird, and Beach Mouse Nesting Distributions Within the South Atlantic Landscape Conservation Cooperative Region

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

Application of fast infrared detectors to detonation science

Infrared radiometers have been used to make time-resolved emission measurements of shocked explosives. Instruments of moderate time resolution were used to estimate temperatures in shocked but not detonated explosives. The heterogeneity of the shock-induced heating was discovered in pressed explosives by two-band techniques, and the time-resolved emittance or extent of hot spot coverage indicated a great dependence on shock pressures. Temperatures in moderately shocked organic liquids were also measured. Faster response radiometers with 5 ns rise times based on InSb and HgCdTe photovoltaic detectors were constructed and tested. Preliminary data on reactive shocks and detonations reveal a resolution of the heating in the shock wave and the following reaction

Do diabetes and depressed mood affect associations between obesity and quality of life in postmenopause? Results of the KORA-F3 Augsburg population study

<p>Abstract</p> <p>Background</p> <p>To assess associations of obesity with health-related quality of life (HRQL) in postmenopausal women, and whether depressed mood and diabetes moderate these associations.</p> <p>Methods</p> <p>Survey of 983 postmenopausal women aged 35-74, general population, Augsburg region/Germany, 2004/2005. Body weight/height and waist/hip circumference were assessed anthropometrically and classified via BMI ≥ 30 as obese, and WHR ≥ 0.85 as abdominally obese (vs. not). Depressed mood was assessed by the Depression and Exhaustion-(DEEX-)scale, diabetes and postmenopausal status by self-report/medication, and HRQL by the SF-12.</p> <p>Results</p> <p>General linear models revealed negative associations of obesity and abdominal obesity with physical but not mental HRQL. Both forms of excess weight were associated with diabetes but not depressed mood. Moderation depended on the HRQL-domain in question. In non-diabetic women, depressed mood was found to amplify obesity-associated impairment in physical HRQL (mean "obese"-"non-obese" difference given depressed mood: -6.4, p < .001; among those without depressed mood: -2.5, p = .003). Reduced mental HRQL tended to be associated with obesity in diabetic women (mean "obese"-"non-obese" difference: -4.5, p = .073), independent of depressed mood. No interactions pertained to abdominal obesity.</p> <p>Conclusions</p> <p>In postmenopausal women, depressed mood may amplify the negative impact of obesity on physical HRQL, while diabetes may be a precondition for some degree of obesity-related impairments in mental HRQL.</p