344 research outputs found
A homogeneous method for investigation of methylation-dependent protein–protein interactions in epigenetics
Methylation of lysine residues on the tails of histone proteins is a major determinant of the transcription state of associated DNA coding regions. The interplay among methylation states and other histone modifications to direct transcriptional outcome is referred to as the histone code. In addition to histone methyltransferases and demethylases which function to modify the methylation state of lysine sidechains, other proteins recognize specific histone methylation marks essentially serving as code readers. While these interactions are highly specific with respect to site and methylation state of particular lysine residues, they are generally weak and therefore difficult to monitor by traditional assay techniques. Herein, we present the design and implementation of a homogeneous, miniaturizable, and sensitive assay for histone methylation-dependent interactions. We use AlphaScreen, a chemiluminescence-based technique, to monitor the interactions of chromodomains (MPP8, HP1β and CHD1), tudor domains (JMJD2A) and plant homeodomains (RAG2) with their cognate trimethyllysine histone partners. The utility of the method was demonstrated by profiling the binding specificities of chromo- and tudor domains toward several histone marks. The simplicity of design and the sensitive and robust nature of this assay should make it applicable to a range of epigenetic studies, including the search for novel inhibitors of methylation-dependent interactions
Ultracool Field Brown Dwarf Candidates Selected at 4.5 microns
We have identified a sample of cool field brown dwarf candidates using IRAC
data from the Spitzer Deep, Wide-Field Survey (SDWFS). The candidates were
selected from 400,000 SDWFS sources with [4.5] <= 18.5 mag and required to have
[3.6]-[4.5] >= 1.5 and [4.5] - [8.0] <= 2.0 on the Vega system. The first color
requirement selects objects redder than all but a handful of presently known
brown dwarfs with spectral classes later than T7, while the second eliminates
14 probable reddened AGN. Optical detection of 4 of the remaining 18 sources
implies they are likely also AGN, leaving 14 brown dwarf candidates. For two of
the brightest candidates (SDWFS J143524.44+335334.6 and SDWFS
J143222.82+323746.5), the spectral energy distributions including near-infrared
detections suggest a spectral class of ~ T8. The proper motion is < 0.25 "/yr,
consistent with expectations for a luminosity inferred distance of >70 pc. The
reddest brown dwarf candidate (SDWFS J143356.62+351849.2) has [3.6] -
[4.5]=2.24 and H - [4.5] > 5.7, redder than any published brown dwarf in these
colors, and may be the first example of the elusive Y-dwarf spectral class.
Models from Burrows et al. (2003) predict larger numbers of cool brown dwarfs
should be found for a Chabrier (2003) mass function. Suppressing the model
[4.5] flux by a factor of two, as indicated by previous work, brings the
Burrows models and observations into reasonable agreement. The recently
launched Wide-field Infrared Survey Explorer (WISE) will probe a volume ~40x
larger and should find hundreds of brown dwarfs cooler than T7.Comment: 13 pages, 6 figures, accepted for publication in the June 2010 issue
of The Astronomical Journa
HIV Prevention in Care and Treatment Settings: Baseline Risk Behaviors among HIV Patients in Kenya, Namibia, and Tanzania.
HIV care and treatment settings provide an opportunity to reach people living with HIV/AIDS (PLHIV) with prevention messages and services. Population-based surveys in sub-Saharan Africa have identified HIV risk behaviors among PLHIV, yet data are limited regarding HIV risk behaviors of PLHIV in clinical care. This paper describes the baseline sociodemographic, HIV transmission risk behaviors, and clinical data of a study evaluating an HIV prevention intervention package for HIV care and treatment clinics in Africa. The study was a longitudinal group-randomized trial in 9 intervention clinics and 9 comparison clinics in Kenya, Namibia, and Tanzania (N = 3538). Baseline participants were mostly female, married, had less than a primary education, and were relatively recently diagnosed with HIV. Fifty-two percent of participants had a partner of negative or unknown status, 24% were not using condoms consistently, and 11% reported STI symptoms in the last 6 months. There were differences in demographic and HIV transmission risk variables by country, indicating the need to consider local context in designing studies and using caution when generalizing findings across African countries. Baseline data from this study indicate that participants were often engaging in HIV transmission risk behaviors, which supports the need for prevention with PLHIV (PwP). TRIAL REGISTRATION: ClinicalTrials.gov NCT01256463
Effect of different cleaning procedures on water use and bacterial levels in weaner pig pens
peer reviewedPork is one of the most globally eaten meats and the pig production chain contributes significantly to the water footprint of livestock production. However, very little knowledge is available about the on-farm factors that influence freshwater use in the pig production chain. An experiment was conducted to quantify the effect of three different washing treatments on freshwater use, bacterial levels [(total bacterial counts; TBC), Enterobacteriaceae and Staphylococcus] and cleaning time in washing of pens for weaning pigs. Three weaner rooms were selected with each room having 10 pens and a capacity to hold up to 14 pigs each. Pigs were weaned and kept in the pens for 7 weeks. Finally, the pens were cleaned before the next batch of pigs moved in. The washing treatments used were power washing and disinfection (WASH); presoaking followed by power washing and disinfection (SOAK), and presoaking followed by detergent, power washing and disinfection (SOAK + DETER). A water meter was used to collect water use data and swab samples were taken to determine the bacterial levels. The results showed that there was no overall effect of washing treatments on water use. However, there was an effect of treatment on the washing time (p<0.01) with SOAK and SOAK+DETER reducing the washing time per pen by 2.3 minutes (14%) and 4.2 minutes (27%) compared to WASH. Nonetheless, there was an effect of sampling time (before or after washing) (p<0.001) on the levels of TBC and Staphylococcus, but no effect was seen on Enterobacteriaceae levels. Thus, the washing treatments used in this study had no effect on the water use of the pork production chain. Although there was no difference in both water use and bacterial load, from a producer perspective, presoaking and detergent use can save time and labour costs, so this would be the preferred option
The Grizzly, February 28, 2002
Doug Farah Pays a Visit to Ursinus • Ursinus Students in Who\u27s Who List • Mysterious Rash Hits School Children Across the Country • Welcome to the Real World • Xanax Abuse • Controversy in the World of Figure Skating • Opinions: Spring Break; Sprinklers: Where are They?; Italy for a Semester • Experience the Beauty of Spring at the Philadelphia Flower Show • Marisol: A Different but Successful Performance at Ursinus College • Some Hot Tips for an Exciting and Safe Spring Break in Sunny Mexico • Track Team\u27s Results from Haverford • Men\u27s Basketball Falls Short at F&M • Men\u27s Rugby Team Admitted to Eastern Pennsylvania Rugby Union • Kings of the Court • Aivazian says Bye, Bye, Bye to the Division I Competition at UPenn • UC Swimmers Turn Up the Heat in the Water at the 2002 CC Championship Meethttps://digitalcommons.ursinus.edu/grizzlynews/1509/thumbnail.jp
Using Medical Students to Enhance Curricular Integration of Cross-Cultural Content
We hypothesized that an interested medical student group would be helpful in reviewing tutorial cases and giving relevant feedback on the curricular integration of cross-cultural content using case triggers in a preclinical gastrointestinal pathophysiology course. Self-selected student leaders (n = 9) reviewed pre-existing problem-based learning tutorial cases (n = 3) with cross-cultural triggers, and provided narrative feedback to course faculty. The cases were modified and used for the entire class in the following 2 years. Participating course students' comments and teaching faculty feedback were also noted. Outcomes were a change in case content, student global evaluations of the course, and self-reported faculty comfort with teaching the cases. All three tutorial cases were reviewed by a separate group of 2–3 students. Major and minor revisions were made to each case based on the student feedback. These cases were used in 2007 and 2008 and were the major change to the course during that time. Overall course evaluation scores improved significantly from 2006 to 2008 (p = 0.000). Tutors (n = 22 in 2007; n = 23 in 2008) expressed relief during tutor meetings that students had reviewed the cases. A general framework for eliciting student feedback on problem-based cases was developed. Student feedback, consisting of self-selected students' case reviews and solicited course and tutor comments, added value to a curricular reform to improve the integration of cross-cultural content into a problem-based learning curriculum. Our study underscores the fundamental link between teachers and students as partners in curricular development
Organizational correlates of adolescent immunization: Findings of a state-wide study of primary care clinics in North Carolina
To analyze organization-level correlates of immunization coverage among adolescents served by high-volume primary care providers in North Carolina
Do Female Residents Actually Demonstrate Better Levels of Empathy, Emotional Intelligence and Burnout than their Male Counterparts?
The Milky Way Tomography With SDSS. III. Stellar Kinematics
We study Milky Way kinematics using a sample of 18.8 million main-sequence stars with r 20 degrees). We find that in the region defined by 1 kpc < Z < 5 kpc and 3 kpc < R < 13 kpc, the rotational velocity for disk stars smoothly decreases, and all three components of the velocity dispersion increase, with distance from the Galactic plane. In contrast, the velocity ellipsoid for halo stars is aligned with a spherical coordinate system and appears to be spatially invariant within the probed volume. The velocity distribution of nearby (Z < 1 kpc) K/M stars is complex, and cannot be described by a standard Schwarzschild ellipsoid. For stars in a distance-limited subsample of stars (< 100 pc), we detect a multi-modal velocity distribution consistent with that seen by HIPPARCOS. This strong non-Gaussianity significantly affects the measurements of the velocity-ellipsoid tilt and vertex deviation when using the Schwarzschild approximation. We develop and test a simple descriptive model for the overall kinematic behavior that captures these features over most of the probed volume, and can be used to search for substructure in kinematic and metallicity space. We use this model to predict further improvements in kinematic mapping of the Galaxy expected from Gaia and the Large Synoptic Survey Telescope.NSF AST-615991, AST-0707901, AST-0551161, AST-02-38683, AST-06-07634, AST-0807444, PHY05-51164NASA NAG5-13057, NAG5-13147, NNXO-8AH83GPhysics Frontier Center/Joint Institute for Nuclear Astrophysics (JINA) PHY 08-22648U.S. National Science FoundationMarie Curie Research Training Network ELSA (European Leadership in Space Astrometry) MRTN-CT-2006-033481Fermi Research Alliance, LLC, United States Department of Energy DE-AC02-07CH11359Alfred P. Sloan FoundationParticipating InstitutionsJapanese MonbukagakushoMax Planck SocietyHigher Education Funding Council for EnglandMcDonald Observator
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