A Man\u27s Game: Analysis of the Gender Divide in Chess

From the Washington University Office of Undergraduate Research Digest (WUURD), Vol. 12, 05-01-2017. Published by the Office of Undergraduate Research. Joy Zalis Kiefer, Director of Undergraduate Research and Associate Dean in the College of Arts & Sciences; Lindsey Paunovich, Editor; Helen Human, Programs Manager and Assistant Dean in the College of Arts and Sciences Mentor: Eileen G\u27Sel

Obliquity Constraints on an Extrasolar Planetary-Mass Companion

We place the first constraints on the obliquity of a planetary-mass companion outside of the solar system. Our target is the directly imaged system 2MASS J01225093–2439505 (2M0122), which consists of a 120 Myr 0.4 M⊙ star hosting a 12–27 M_J companion at 50 au. We constrain all three of the system's angular-momentum vectors: how the companion spin axis, the stellar spin axis, and the orbit normal are inclined relative to our line of sight. To accomplish this, we measure projected rotation rates (v sin i) for both the star and the companion using new near-infrared high-resolution spectra with NIRSPEC at Keck Observatory. We combine these with a new stellar photometric rotation period from TESS and a published companion rotation period from Hubble Space Telescope to obtain spin-axis inclinations for both objects. We also fitted multiple epochs of astrometry, including a new observation with NIRC2/Keck, to measure 2M0122b's orbital inclination. The three line-of-sight inclinations place limits on the true de-projected companion obliquity and stellar obliquity. We find that while the stellar obliquity marginally prefers alignment, the companion obliquity tentatively favors misalignment. We evaluate possible origin scenarios. While collisions, secular spin–orbit resonances, and Kozai–Lidov oscillations are unlikely, formation by gravitational instability in a gravito-turbulent disk—the scenario favored for brown dwarf companions to stars—appears promising

The Impact of Dosing Interval in a Novel Tandem Oral Dosing Strategy: Enhancing the Exposure of Low Solubility Drug Candidates in a Preclinical Setting

In drug discovery, time and resource constraints necessitate increasingly early decision making to accelerate or stop preclinical programs. Early discovery drug candidates may be potent inhibitors of new targets, but all too often exhibit poor pharmaceutical or pharmacokinetic properties that limit the in vivo exposure. Low solubility of a drug candidate often leads to poor oral bioavailability and poor dose linearity. This issue is more significant for efficacy and target safety studies where high drug exposures are desired. When solubility issues are confronted, enabling formulations are often required to improve the exposure. However, this approach often requires a substantial and lengthy investment to develop the formulation. Previously, we introduced a gastrointestinal (GI) transit time-based novel oral tandem dosing strategy that enhanced in vivo exposures in rats. In this study, a refined time interval versus dose theory was tested. The resulting in vivo exposures based on altering frequency and doses were compared, and significant impacts were found

Unilateral cleft lip repair: Technical maneuvers to achieve vermilion and mucosal height

Patients with unilateral cleft lip often require secondary procedures due to asymmetric fullness or deficiencies along the mucosal free margin of the upper lip. Here, we describe our technique for mucosal advancement and repair to attain symmetry. Methods: Maneuvers to obtain vermilion and mucosal height include (1) use of a tailored vermilion flap; (2) supraperiosteal release of the lesser segment; (3) backcut poker incision to mobilize the mucosal flap on the lesser segment; (4) transverse release of mucosa across the greater segment; (5) accurate reduction along vermilion-mucosal junction; and (6) bilateral medial mucosal advancement. To examine postoperative outcomes, photographic data were available for 14 patients with unilateral complete cleft lip. The Cleft Lip Component Symmetry Index was then calculated as a ratio of upper lip height on cleft to noncleft sides, where an index of 1 indicates symmetry. Results: Sixteen consecutive patients underwent unilateral cleft lip repair with this technique over a 3-year period, none of whom have required secondary operations. The symmetry index for 14 of 16 patients was 1.02 ± 0.11 (95% confidence interval [0.96, 1.08], Conclusions: Postoperative asymmetry after unilateral cleft lip repair, particularly along the free margin, continues to be a common problem, necessitating secondary procedures. The technique of mucosal repair merits more careful attention than it has previously received, and here we describe in detail a method that has allowed for improved symmetry

Polymorphism and selection of rpoS in pathogenic Escherichia coli

<p>Abstract</p> <p>Background</p> <p>Though RpoS is important for survival of pathogenic <it>Escherichia coli </it>in natural environments, polymorphism in the <it>rpoS </it>gene is common. However, the causes of this polymorphism and consequential physiological effects on gene expression in pathogenic strains are not fully understood.</p> <p>Results</p> <p>In this study, we found that growth on non-preferred carbon sources can efficiently select for loss of RpoS in seven of ten representative verocytotoxin-producing <it>E. coli </it>(VTEC) strains. Mutants (Suc⁺⁺) forming large colonies on succinate were isolated at a frequency of 10^-8mutants per cell plated. Strain O157:H7 EDL933 yielded mainly mutants (about 90%) that were impaired in catalase expression, suggesting the loss of RpoS function. As expected, inactivating mutations in <it>rpoS </it>sequence were identified in these mutants. Expression of two pathogenicity-related phenotypes, cell adherence and RDAR (red dry and rough) morphotype, were also attenuated, indicating positive control by RpoS. For the other Suc⁺⁺mutants (10%) that were catalase positive, no mutation in <it>rpoS </it>was detected.</p> <p>Conclusion</p> <p>The selection for loss of RpoS on poor carbon sources is also operant in most pathogenic strains, and thus is likely responsible for the occurrence of <it>rpoS </it>polymorphisms among <it>E. coli </it>isolates.</p

Preparation of neuronal co-cultures with single cell precision

Microfluidic embodiments of the Campenot chamber have attracted great interest from the neuroscience community. These interconnected co-culture platforms can be used toinvestigate a variety of questions, spanning developmental and functional neurobiology to infection and disease propagation. However, conventional systems require significant cellular inputs (many thousands per compartment), inadequate for studying low abundance cells, such as primary dopaminergic substantia nigra, spiral ganglia and Drosophilia melanogaster neurons, and impractical for high throughput experimentation. The dense cultures are also highly locally entangled, with few outgrowths (&lt;10%) interconnecting the two cultures. In this paper straightforward microfluidic and patterning protocols are described which address these challenges: (i) a microfluidic single neuron arraying method, and (ii) a water masking method for plasma patterning biomaterial coatings to register neurons and promote outgrowth between compartments. Minimalistic neuronal co-cultures were prepared with high-level (&gt;85%) inter-compartment connectivity and can be used for high throughput neurobiology experiments with single cell precisio

Astrocyte-specific regulation of hMeCP2 expression in \u3ci\u3eDrosophila\u3c/i\u3e

Alterations in the expression of Methyl-CpG-binding protein 2 (MeCP2) either by mutations or gene duplication leads to a wide spectrum of neurodevelopmental disorders including Rett Syndrome and MeCP2 duplication disorder. Common features of Rett Syndrome (RTT), MeCP2 duplication disorder, and neuropsychiatric disorders indicate that even moderate changes in MeCP2 protein levels result in functional and structural cell abnormalities. In this study, we investigated two areas of MeCP2 pathophysiology using Drosophila as a model system: the effects of MeCP2 glial gain-of-function activity on circuits controlling sleep behavior, and the cell-type specific regulation of MeCP2 expression. In this study, we first examined the effects of elevated MeCP2 levels on microcircuits by expressing human MeCP2 (hMeCP2) in astrocytes and distinct subsets of amine neurons including dopamine and octopamine (OA) neurons. Depending on the celltype, hMeCP2 expression reduced sleep levels, altered daytime/ nighttime sleep patterns, and generated sleep maintenance deficits. Second, we identified a 498 base pair region of the MeCP2e2 isoform that is targeted for regulation in distinct subsets of astrocytes. Levels of the full-length hMeCP2e2 and mutant RTT R106W protein decreased in astrocytes in a temporally and spatially regulated manner. In contrast, expression of the deletion D166 hMeCP2 protein was not altered in the entire astrocyte population. qPCR experiments revealed a reduction in full-length hMeCP2e2 transcript levels suggesting transgenic hMeCP2 expression is regulated at the transcriptional level. Given the phenotypic complexities that are caused by alterations in MeCP2 levels, our results provide insight into distinct cellular mechanisms that control MeCP2 expression and link microcircuit abnormalities with defined behavioral deficits

Gender Differences in Social Mortality Differentials in Switzerland (1990-2005)

Using data from the 1990 and 2000 Swiss Federal Censuses linked to the death records of the years 1990-1995 and 2000-2005, this paper investigates gender differences in mortality differentials by level of educational achievement and by marital status. In both periods, the differential by level of education is clearly more pronounced among men, but the difference in the educational gradient between men and women decreases between the two periods of observation. Health behavior might contribute to the gender difference in the educational mortality gradient, but it is probably not the main reason for this finding. The mortality differential by marital status is also stronger in men, but the difference between men and women narrows over time. Our analysis also shows that gender differences in the mortality differential by marital status almost disappear when gender differences in population composition by level of education, nationality, employment status, and housing situation are taken into account