DLC-1 Over-Expression and Growth Inhibition in Saccharomyces Cerevisiae

The activity and regulation of RNA-binding proteins (RBP) is an important topic in studies of gene expression. The regulation of RBPs includes interactions with cofactors. One cofactor that our lab has identified is DLC-1, a small protein that prompts the association of a RBP with subcellular RNA granules. Previous research on a protein, Pbp1, with similar effects in Saccharomyces cerevisiae (yeast) shows that Pbp-1 over-expression leads to growth inhibition in yeast cells due to the promotion of excessive RNA granule formation (Swisher and Parker, 2010). Due to similar effects between Pbp-1 and DLC-1, we hypothesize that DLC-1, when over-expressed, will cause growth inhibition in yeast cells. Saccharomyces cerevisiae is the model organism that we will use to investigate this question because it is cost efficient, allows for fast results, and is relevant for humans because many of the proteins present in yeast have mammalian orthologs. This hypothesis will be tested on multiple strains of yeast. Using these different strains, we will express DLC-1, two positive controls (Pab1 and Dhh1), and a negative control under the control of a galactose-inducible promotor. We will then grow the yeast on agarose plates that contain different concentrations of sugars (galactose and sucrose). We vary the concentrations of sugars in order to control the activity of the promotor, resulting in protein over-expression in higher concentrations of galactose. The yeast will then be incubated on the plates for five days. At the end of the incubation period, potential lack of cell growth on the high-galactose plate will suggest if DLC-1 over-expression does lead to inhibition of cell growth. Understanding how expression of DLC-1 is related to cell growth and RNA granule formation is important because abnormal RNA granule formation is linked to neurodegenerative diseases

Parent Expectations of Elementary Schools and The Leaders, Teachers, and Staff: An Examination of Elementary Schools in a Southeastern Georgia School District

Public schools are experiencing major demographic shifts in the school-age population (Hardy, 2004; Hartman, 2002; Olson, 2005; Rodriguez, 2002; Zehr, 2000). As schools attempt to address the challenges that accompany increasing demographic changes in public schools, a key component of their efforts should include determining parental expectations and how those expectations differ and are influenced by demographics such as race and ethnicity, SES, and level of educational attainment of the parents. Elementary schools must respond to parental expectations in a manner that helps to establish a foundation for students to reach their academic potential, thus providing a quality of education that transcends demographic boundaries and closes the achievement gap between students. This study explored parent expectations of elementary schools and sought to examine the similarities and differences in parent expectations based on the race and ethnicity of the parent, the socioeconomic status of the parent, and the level of educational attainment of the parent. Data was collected from parents who had children in grades 3, 4, or 5 in public elementary schools in a Southeast Georgia school district. This research was driven by the existence of an ever-changing demographic population, Epstein’s Model of Parent Involvement which supports strong partnership between the school and the parents, and the Vygotskyan perspective which supports the manifestation of parents’ aspirations for children as a result of their communication of expectations to the child. Descriptive statistics were generated for analysis along with frequency tables and a one-way ANOVA to determine if significant differences existed between participant responses within demographic groups. The researcher used a quantitative research method with a researcher-created survey. Survey results determined that parent expectations of elementary schools were similar in most areas of School-Parent Relationships, Curriculum, Culture and Climate, Educational Level and Achievement (Growth in Learning), and Parent Involvement. Significant differences were found in the each demographic area which was targeted in the research

Ella B. Brown Oral History

An interview of the Washington University Medical Center Desegregation History Project, conducted by Edwin W. McCleskey and associates, 1990. Approximate Length: 22 minutes. Please note that edits made by Brown have been incorporated into the interview transcript so there is some discrepancy between the audio recording and the final transcript. Ella Brown discusses her experiences at Homer G. Phillips Hospital, where she served as director of nursing service at the time of its closure, and the effect the closing of the hospital had on health care for the Black community. Brown relates her memories of the closure of Homer G. Phillips Hospital and the pain she felt. She discusses the political and economic issues at play, and later explains the logistics involved in closing the hospital and provides details from its last day of operation. She also discusses the connection between the hospital and Washington University, and the merger of the Homer G. Phillips School of Nursing with St. Louis City Hospital Training School for Nurses in 1966

Transgenerational Sterility in fbf-1 and rrf-1 Mutant Caenorhabditis elegans

The interaction between RNAs and RNA-binding proteins (RBPs) is an important topic in studies of gene expression. Our lab is interested in fbf-1, a gene that encodes an RBP that maintains stem cell proliferation and differentiation, and rrf-1, a gene that encodes an RNA-polymerase that generates small regulatory RNAs. These RNAs have been proposed to contribute to the function of FBF genes, but this hypothesis remains controversial in the field. Through previous lab research, we suspected that at 24°C, a strain of Caenorhabditis elegans (C. elegans) with rrf-1 and fbf-1 mutations becomes sterile over the course of multiple generations. Due to this finding, we decided to investigate if the rate at which rrf-1 and fbf-1 mutant C. elegans become sterile at 24°C changes based on how the mutant is produced. We use the model organism C. elegans because many of the proteins present in C. elegans have mammalian orthologs. We will generate the mutant strain in two ways. The first method is to produce a strain that has a fbf-1 deletion but maintains a wild type (WT) copy of rrf-1 through the use of a genetic balancer, a genetic tool that stabilizes a WT gene copy in heterozygotes. We hypothesize that the rrf-1 and fbf-1 mutant progeny of this strain will become sterile at over time at 24°C because the RRF-1-generated small RNAs they have inherited will be depleted each generation. The second method is to produce a strain that has an rrf-1 deletion but maintains a WT copy of fbf-1 using a genetic balancer. We hypothesize that the rrf-1 and fbf-1 mutant progeny will become sterile at 24°C immediately because they did not inherit RRF-1-generated small RNAs. Understanding the link between small regulatory RNAs and RBPs is important because their interaction is implicated in many human diseases, including cancer

A New Custodian for a Realistic Higgsless Model

We present an example of a realistic Higgsless model that makes use of alternative $SU(2)_R$ assignments for the top and bottom quarks recently proposed by Agashe et al. which results in an enhanced custodial symmetry. Using these new representat ions reduces the deviations in the $Zb_\ell\bar{b}_\ell$ coupling to $\sim 4$ for a wide range of parameters, while this remaining correction can also be eliminated by varying the localization parameter (bulk mass) for $b_r$.Comment: 11 pages, 2 figure

The Minimal Set of Electroweak Precision Parameters

We present a simple method for analyzing the impact of precision electroweak data above and below the Z-peak on flavour-conserving heavy new physics. We find that experiments have probed about ten combinations of new physics effects, which to a good approximation can be condensed into the effective oblique parameters Shat, That, Uhat, V, X, W, Y (we prove positivity constraints W, Y >= 0) and three combinations of quark couplings (including a distinct parameter for the bottom). We apply our method to generic extra Z' vectors.Comment: 22 pages, 3 figure

Growth and optical characterisation of multilayers of InGaN quantum dots

We report on the growth (using metal-organic vapour phase epitaxy) and optical characterization of single and multiple layers of InGaN quantum dots (QDs), which were formed by annealing InGaN epilayers at the growth temperature in nitrogen. The size and density of the nanostructures have been found to be fairly similar for uncapped single and three layer QD samples if the GaN barriers between the dot layers are grown at the same temperature as the InGaN epilayer. The distribution of nanostructure heights of the final QD layer of three is wider and is centred around a larger size if the GaN barriers are grown at two temperatures (first a thin layer at the dot growth temperature, then a thicker layer at a higher temperature). Micro-photoluminescence studies at 4.2 K of capped samples have confirmed the QD nature of the capped nanostructures by the observation of sharp emission peaks with full width at half maximum limited by the resolution of the spectrometer. We have also observed much more QD emission per unit area in a sample with three QD layers, than in a sample with a single QD layer, as expected

The social life of time and methods: studying London’s temporal architectures

This paper contributes to work on the social life of time. It focuses on how time is doubled; produced by and productive of the relations and processes it operates through. In particular, it explores the methodological implications of this conception of time for how social scientists may study the doubledness of time. It draws on an allied move within the social sciences to see methods as themselves doubled; as both emerging from and constitutive of the social worlds that they seek to understand. We detail our own very different methodological experiments with studying the social life of time in London, engaging interactive documentary to elucidate nonlinear imaginaries of space-time in London’s pop-up culture (Ella Harris) and encountering time on a series of walks along a particular stretch of road in south east London (Beckie Coleman). While clearly different projects in terms of their content, ambition and scope, in bringing these projects together we show the ability of our methods to grasp and perform from multiple angles and scales what Sharma calls ‘temporal architectures’. Temporal architectures, composed of elements including the built environment, commodities, services, technologies and labour, are infrastructures that enable social rhythms and temporal logics and that can entail a politicized valuing of the time of certain groups over others. We aim to contribute to an expanded and enriched conceptualisation of methods for exploring time, considering what our studies might offer to work on the doubled social life of time and methods, and highlighting in particular their implications for an engagement with a politics of time and temporality

Pump-Enhanced Continuous-Wave Magnetometry using Nitrogen-Vacancy Ensembles

Ensembles of nitrogen-vacancy centers in diamond are a highly promising platform for high-sensitivity magnetometry, whose efficacy is often based on efficiently generating and monitoring magnetic-field dependent infrared fluorescence. Here we report on an increased sensing efficiency with the use of a 532-nm resonant confocal cavity and a microwave resonator antenna for measuring the local magnetic noise density using the intrinsic nitrogen-vacancy concentration of a chemical-vapor deposited single-crystal diamond. We measure a near-shot-noise-limited magnetic noise floor of 200 pT/$\sqrt{\text{Hz}}$ spanning a bandwidth up to 159 Hz, and an extracted sensitivity of approximately 3 nT/$\sqrt{\text{Hz}}$, with further enhancement limited by the noise floor of the lock-in amplifier and the laser damage threshold of the optical components. Exploration of the microwave and optical pump-rate parameter space demonstrates a linewidth-narrowing regime reached by virtue of using the optical cavity, allowing an enhanced sensitivity to be achieved, despite an unoptimized collection efficiency of <2 %, and a low nitrogen-vacancy concentration of about 0.2 ppb.Comment: 10 pages and 5 figure