Permutation and Monomial Progenitors

We searched monomial and permutation progenitors for symmetric presentations of important images, nonabelian simple groups, their automorphism groups, or groups that have these as their factor groups. In this thesis, we described our search for the homomorphic images through the permutation progenitor 2*15:(D5 X 3) and construction of a monomial representation through the group 23:3. We constructed PGL(2,7) over 23:3 on 6 letters and L2(11) over 22:3 on 8 letters. We also give our construction of S5 X 2 and L2(25) as homomorphic images of the monomial progenitor 3*3:mD4. In addition, we describe how to solve the extension problem for finite groups through the example of the group (4X22):.A4

You Kind of Have to Prove It: Gender Microaggressions within the Lived Experiences of Women in Engineering

This intrinsic case study explored the lived experiences of women within three engineering majors at a mid-sized institution in the Mid-Atlantic using gender microaggressions (Nadal, 2010; Sue, 2007) as a theoretical lens. Data included individual interviews with 28 participants as well as document review from Web pages and observations from physical spaces within the campus engineering building. Data analysis resulted in seven themes in congruence with Sue’s (2007) taxonomy of gender microaggressions and further established the three levels of gender microaggressions distinguished by Nadal (2010). Findings also revealed that barriers within engineering were less visible or outwardly sexist, and that gender microaggressions shaped the experiences of undergraduate women in engineering majors by creating an atmosphere in which women feel the need to prove they belong. Implications suggest the importance of administrators charged with overseeing engineering programs finding ways to help women feel more supported and socialized with one another within engineering departments and the need to educate faculty and staff working with students about the effects of subtle messaging on women

STEM as "Minority": A Phenomenological Case Study of How Students of Color Perceive Their Experience in a STEM Living-Learning Program

The future of the U.S. scientific workforce depends on graduating college students in science, technology, engineering, and math (STEM) fields. The completion rate of STEM students is a national concern, especially among students of color. This qualitative study examines the experiences of students of color in a living-learning program for STEM students. Five themes were discovered from students’ meaning-making. Four of the themes integrate well with existing literature. The fifth theme, STEM as Minority, was not found in the literature and is a new contribution to the field of knowledge on how environments can be purposed to support STEM students

Strategic Public Relations Plan: Springfield’s Adopt-A-Waterway Program

62 pagesSpringfield believes that most pollution by residents can be attributed to a lack of awareness and have tasked this class of Journalism and Communications students to conduct a public relations campaign and make recommendations on which characteristics of the Adopt-A-Waterway program would be most appealing to residents. This report contains a Strategic Public Relations Plan and a Research Report. The Public Relations Plan highlights key publics, objectives, strategies, and tactics for five groups: (1) middle school science teachers and student group faculty advisers, (2) high school group leaders and student group faculty advisers, (3) church group leaders, (4) service group leaders, and (5) Springfield residents

Modificación de la superficie de un electrodo selectivo a acetilcolina con materiales nanoestructurados para la detección de pesticidas en un sistema bio-electroquímico

93 páginas. Maestría en Ciencias e Ingeniería de Materiales.En este trabajo se presenta la construcción de un electrodo potenciométrico selectivo a iones de Acetilcolina, el cual demostró ser eficiente en la detección de carbamatados, en específico del Propoxur, dentro de un sistema bio-electroquímico, el cual consta de una solución en la que se encuentra la Acetilcolina, la enzima y el pesticida. Para la construcción del electrodo, se tomaron en cuenta parámetros como la composición de la membrana polimérica, su selectividad ante diversos cationes y el tiempo de acondicionamiento de la misma. Además, se modificó el electrodo con Nanopartículas de Oro (NPsAu) con el objetivo de aumentar tanto la sensibilidad del electrodo, como la selectividad ante el ion de interés. Finalmente se realizó la determinación del pesticida mediante la inhibición de la enzima Acetilcolinaesterasa dentro del sistema bio-electroquímico propuesto.Consejo Nacional de Ciencia y Tecnología (México)

Analysis of the Factors that Limit the Ability of Feeder Cells to Maintain the Undifferentiated State of Human Embryonic Stem Cells

Human embryonic stem cell (hESC) culture is routinely performed using inactivated mouse embryonic fibroblasts (MEFs) as a feeder cell layer (FL). Although these cells maintain pluripotency of hESCs, the molecular basis for this is unknown. Objectives of this study were to determine whether timing between MEF inactivation and their use as a FL influenced hESC growth and differentiation, and to begin defining the mechanism(s) involved. hESCs were plated on MEFs prepared 1 (MEF-1), 4 (MEF-4), and 7 (MEF-7) days earlier. hESC colony morphology and Oct3/4 expression levels were evaluated to determine the influence of different FLs. Significant enhancement of hESC growth (self-renewal) was observed on MEF-1 compared with MEF-4 and/or MEF-7. Conditioned media (CM) collected from MEF-1 supported significantly better hESC growth in a FL-free system compared to MEF-7 CM. Effects of MEFs on hESC growth were not caused by differences in cell density or viability, although indications of apoptosis were observed in MEF-7. Scanning electron microscopy demonstrated that MEF-7 were morphologically distinct from MEF-1 and MEF-4. Microarray analysis identified 19 genes related to apoptosis with significantly different levels of expression between MEF-1 and MEF-7. Several differentially expressed RNAs had gene ontology classifications associated with extracellular matrix (ECM) structural constituents and growth factors. Because members of Wnt signaling pathway were identified in the array analysis, we examined the ability of the Wnt1 CM and secreted frizzled-related proteins to affect hESC growth and differentiation. The addition of Wnt1 CM to both MEF-1 and MEF-7 significantly increased the number of undifferentiated colonies, while the addition of Sfrps promoted differentiation. Together, these results suggest that microenvironment, ECM, and soluble factors expressed by MEF-1 are significantly better at maintaining self-renewal and pluripotency of hESCs. Our findings have important implications in the optimization of hESC culture when MEFs are used as FL or CM is used in FL-free culture.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78130/1/scd.2008.0010.pd

On the difference of torus geometry between hidden and non-hidden broad line active galactic nuclei

We present results from the fitting of infrared (IR) spectral energy distributions of 21 active galactic nuclei (AGN) with clumpy torus models. We compiled high spatial resolution ($\sim 0.3$--$0.7$ arcsec) mid-IR $N$-band spectroscopy, $Q$-band imaging and nuclear near- and mid-IR photometry from the literature. Combining these nuclear near- and mid-IR observations, far-IR photometry and clumpy torus models, enables us to put constraints on the torus properties and geometry. We divide the sample into three types according to the broad line region (BLR) properties; type-1s, type-2s with scattered or hidden broad line region (HBLR) previously observed, and type-2s without any published HBLR signature (NHBLR). Comparing the torus model parameters gives us the first quantitative torus geometrical view for each subgroup. We find that NHBLR AGN have smaller torus opening angles and larger covering factors than those of HBLR AGN. This suggests that the chance to observe scattered (polarized) flux from the BLR in NHBLR could be reduced by the dual effects of (a) less scattering medium due to the reduced scattering volume given the small torus opening angle and (b) the increased torus obscuration between the observer and the scattering region. These effects give a reasonable explanation for the lack of observed HBLR in some type-2 AGN.Comment: 13 pages, 5 figures, accepted for publication in Ap

Revised Architecture and Two New Super-Earths in the HD 134606 Planetary System

Multi-planet systems exhibit a diversity of architectures that diverge from the solar system and contribute to the topic of exoplanet demographics. Radial velocity (RV) surveys form a crucial component of exoplanet surveys, as their long observational baselines allow searches for more distant planetary orbits. This work provides a significantly revised architecture for the multi-planet system HD 134606 using both HARPS and UCLES RVs. We confirm the presence of previously reported planets b, c, and d with periods $12.0897^{+0.0019}_{-0.0018}$, $58.947^{+0.056}_{-0.054}$, and $958.7^{+6.3}_{-5.9}$ days, and masses $9.14^{+0.65}_{-0.63}$, $11.0\pm1$, and $44.5\pm2.9$ Earth masses respectively, with the planet d orbit significantly revised to over double that originally reported. We report two newly detected super-Earths, e and f, with periods $4.31943^{+0.00075}_{-0.00068}$ and $26.9^{+0.019}_{-0.017}$ days, and masses $2.31^{+0.36}_{-0.35}$ and $5.52^{+0.74}_{-0.73}$ Earth masses, respectively. In addition, we identify a linear trend in the RV time series, and the cause of this acceleration is deemed to be a newly detected sub-stellar companion at large separation. HD 134606 now displays four low mass planets in a compact region near the star, one gas giant further out in the Habitable Zone, an additional massive companion in the outer regime, and a low mass M dwarf stellar companion at large separation, making it an intriguing target for system formation/evolution studies. The location of planet d in the Habitable Zone proves to be an exciting candidate for future space-based direct imaging missions, whereas continued RV observations of this system are recommended for understanding the nature of the massive, long period companion.Comment: 23 pages, 10 figures, 4 tables, accepted for publication in the Astronomical Journa

Evaluation of the economic costs and benefits of methods for reducing nutrient loads to the Gulf of Mexico: Topic 6 Report for the Integrated Assessment on Hypoxia in the Gulf of Mexico.

In this report we analyze the Topic 5 report’s recommendations for reducing nitrogen losses to the Gulf of Mexico (Mitsch et al. 1999). We indicate the relative costs and cost-effectiveness of different control measures, and potential benefits within the Mississippi River Basin. For major nonpoint sources, such as agriculture, we examine both national and basin costs and benefits. Based on the Topic 2 economic analysis (Diaz and Solow 1999), the direct measurable dollar benefits to Gulf fisheries of reducing nitrogen loads from the Mississippi River Basin are very limited at best. Although restoring the ecological communities in the Gulf may be significant over the long term, we do not currently have information available to estimate the benefits of such measures to restore the Gulf’s long-term health. For these reasons, we assume that measures to reduce nitrogen losses to the Gulf will ultimately prove beneficial, and we concentrate on analyzing the cost-effectiveness of alternative reduction strategies. We recognize that important public decisions are seldom made on the basis of strict benefit–cost analysis, especially when complete benefits cannot be estimated. We look at different approaches and different levels of these approaches to identify those that are cost-effective and those that have limited undesirable secondary effects, such as reduced exports, which may result in lost market share. We concentrate on the measures highlighted in the Topic 5 report, and also are guided by the source identification information in the Topic 3 report (Goolsby et al. 1999). Nonpoint sources that are responsible for the bulk of the nitrogen receive most of our attention. We consider restrictions on nitrogen fertilizer levels, and restoration of wetlands and riparian buffers for denitrification. We also examine giving more emphasis to nitrogen control in regions contributing a greater share of the nitrogen load