The Function and Regulation of Sleep in Drosophila melanogaster

A key feature of sleep is reduced responsiveness to the environment, which puts animals in a particularly vulnerable state; yet, sleep has been conserved throughout evolution, indicating that it fulfills a vital purpose. A core function of sleep across species has not been identified, but substantial advances in sleep research have been made in recent years using the genetically tractable model organism, Drosophila melanogaster. While a standard approach in sleep research is to study the effects of short-term sleep deprivation on an animal, tools are now available to genetically manipulate sleep amount in the fruit fly. In particular, a number of short-sleeping Drosophila mutants have been identified that model the long-term sleep restriction that is widespread in modern society. This thesis describes a body of work in which short-sleeping Drosophila mutants, as well as other genetic and pharmacological tools, were used to shed light on the function and regulation of sleep

INCREASING STEM PARTICIPATION AND STUDENT SUCCESS OF DEVELOPMENTAL MATHEMATICS STUDENTS AT AN URBAN COMMUNITY COLLEGE

This mixed method, quantitative and qualitative, study explores the effects of a curriculum with an emphasis on scientific, technological, and engineering focused problems and careers on student success and interest in Science, Technology, Engineering, and Mathematics (STEM). The setting is an urban community college where in the spring of 2016, 71% of the students tested into developmental mathematics (STCC, 2017). The course of study was Algebra one, a developmental, non-college credit bearing, mathematics course. Students had the option of two paths for the subsequent course, a terminal college level mathematics class, or a STEM pathway developmental algebra two course. Pass rates, pre/posttests, pre/post interest surveys, and subsequent math course were recorded and analyzed. Furthermore, implications and limitations of the study were examined with recommendations for future research presented. The findings were that there was an increase in both path rates, and STEM interest

Extracting interstellar diffuse absorption bands from cool star spectra: Application to bulge clump giants in Baade's window

Interstellar diffuse bands are usually extracted from hot star spectra because they are characterized by smooth continua. It introduces a strong limitation on the number of available targets, and reduces potential studies of the IS matter and the use of absorptions for cloud mapping. We have developed a new automatic fitting method appropriate to interstellar absorptions in spectra of cool stars that possess stellar atmospheric parameters. We applied this method to the extraction of three DIBs in high resolution VLT FLAMES/GIRAFFE spectra of red clump stars from the bulge. By combining all stellar synthetic spectra, HITRAN-LBLRTM atmospheric transmission spectra and diffuse band empirical absorption profiles, we determine the 6196, 6204, and 6284 A DIB strength toward the 219 target stars and discuss the sources of uncertainties. In order to test the sensitivity of the DIB extraction, we intercompare the three results and compare the DIB equivalent widths with the reddening derived from an independent extinction map based on OGLE photometric data. Most stellar spectra could be well reproduced by the composite stellar, atmospheric and interstellar models. Measurement uncertainties on the EWs are smaller for the broad and strong 6284 A DIB, and are of the order of 10-15%. Uncertainties on the two narrow and weaker DIBs are larger, as expected, and found to be highly variable from one target to the other. They strongly depend on the radial velocity of the star . DIB-DIB correlations among the three bands demonstrate that a meaningful signal is extracted. For the 6284 and 6204 A DIBs, the star-to-star variability of the equivalent width (EW) also reflects features of the OGLE extinction map...Comment: Accepted for publication in A&A. 14 pages+appendix, 15 figures and 3 table

An Examination of the Impact of Union Presence on Social Agendas

Louis J. Pantuosco, PhD, is associate professor of economics in the College of Business at Winthrop University, Rock Hill, SC 29733. Vanessa Hill, PhD, is assistant professor of management in the College of Business at Winthrop University, Rock Hill, SC 29733

Sulphur in the Sculptor dwarf spheroidal galaxy - Including NLTE corrections

In Galactic halo stars, sulphur has been shown to behave like other $\alpha$-elements, but until now, no comprehensive studies have been done on this element in stars of other galaxies. Here, we use high-resolution ESO VLT/FLAMES/GIRAFFE spectra to determine sulphur abundances for 85 stars in the Sculptor dwarf spheroidal galaxy, covering the metallicity range $-2.5\leq \text{[Fe/H]} \leq-0.8$. The abundances are derived from the S~I triplet at 9213, 9228, and 9238~\AA. These lines have been shown to be sensitive to departure from local thermodynamic equilibrium, i.e. NLTE effects. Therefore, we present new NLTE corrections for a grid of stellar parameters covering those of the target stars. The NLTE-corrected sulphur abundances in Sculptor show the same behaviour as other $\alpha$-elements in that galaxy (such as Mg, Si, and Ca). At lower metallicities ($\text{[Fe/H]}\lesssim-2$) the abundances are consistent with a plateau at $\text{[S/Fe]}\approx+0.16$, similar to what is observed in the Galactic halo, $\text{[S/Fe]}\approx+0.2$. With increasing [Fe/H], the [S/Fe] ratio declines, reaching negative values at $\text{[Fe/H]}\gtrsim-1.5$. The sample also shows an increase in [S/Mg] with [Fe/H], most probably because of enrichment from Type Ia supernovae.Comment: 9 pages, 11 figures, 2 tables + 3 online tables, accepted in A&