Zu siebzig Prozent verrückt

Social Entrepreneurs haben oft gleichzeitig effektive wie verrückte Ideen. Doch zur Umsetzung ihrer Ansätze brauchen sie förderliche Rahmenbedingungen. Zahlreiche Akteure können auf unterschiedliche Weise zur Unterstützung von Social Entrepreneurship beitragen

Genomic analysis of insertion behavior and target specificity of mini-Tn7 and Tn3 transposons in Saccharomyces cerevisiae

Transposons are widely employed as tools for gene disruption. Ideally, they should display unbiased insertion behavior, and incorporate readily into any genomic DNA to which they are exposed. However, many transposons preferentially insert at specific nucleotide sequences. It is unclear to what extent such bias affects their usefulness as mutagenesis tools. Here, we examine insertion site specificity and global insertion behavior of two mini-transposons previously used for large-scale gene disruption in Saccharomyces cerevisiae: Tn3 and Tn7. Using an expanded set of insertion data, we confirm that Tn3 displays marked preference for the AT-rich 5 bp consensus site TA[A/T]TA, whereas Tn7 displays negligible target site preference. On a genome level, both transposons display marked non-uniform insertion behavior: certain sites are targeted far more often than expected, and both distributions depart drastically from Poisson. Thus, to compare their insertion behavior on a genome level, we developed a windowed Kolmogorov–Smirnov (K–S) test to analyze transposon insertion distributions in sequence windows of various sizes. We find that when scored in large windows (>300 bp), both Tn3 and Tn7 distributions appear uniform, whereas in smaller windows, Tn7 appears uniform while Tn3 does not. Thus, both transposons are effective tools for gene disruption, but Tn7 does so with less duplication and a more uniform distribution, better approximating the behavior of the ideal transposon

A Multi-Epoch HST Study of the Herbig-Haro Flow from XZ Tauri

We present nine epochs of Hubble Space Telescope optical imaging of the bipolar outflow from the pre-main sequence binary XZ Tauri. Our data monitors the system from 1995-2005 and includes emission line images of the flow. The northern lobe appears to be a succession of bubbles, the outermost of which expanded ballistically from 1995-1999 but in 2000 began to deform and decelerate along its forward edge. It reached an extent of 6" from the binary in 2005. A larger and fainter southern counterbubble was detected for the first time in deep ACS images from 2004. Traces of shocked emission are seen as far as 20" south of the binary. The bubble emission nebulosity has a low excitation overall, as traced by the [S II]/H-alpha line ratio, requiring a nearly comoving surrounding medium that has been accelerated by previous ejections or stellar winds. Within the broad bubbles there are compact emission knots whose alignments and proper motions indicate that collimated jets are ejected from each binary component. The jet from the southern component, XZ Tau A, is aligned with the outflow axis of the bubbles and has tangential knot velocities of 70-200 km/s. Knots in the northern flow are seen to slow and brighten as they approach the forward edge of the outermost bubble. The knots in the jet from the other star, XZ Tau B, have lower velocities of ~100 km/s

The Grizzly, October 10, 2013

Annual Ursinus College Crime Report Released • Homecoming 2013 Preview • Religious Faith on Campus • Student Affairs\u27 New Mission Statement • Student Retention • Ursinus\u27 Grizzly Gala Returns • CSCG Features Speaker • Opinion: Ursinus Curates its Web Presence Poorly; We All Need the Stress Management Course • Carty Balances Football and Pre-Law • Golf Prepares for Spring During Fall Season • Football Sits at 5-0, Men\u27s Soccer Takes a Losshttps://digitalcommons.ursinus.edu/grizzlynews/1889/thumbnail.jp

BSAVA Formulary: Your questions answered

A new edition of the BSAVA Small Animal Formulary has been published. Ian Ramsey explains what is in and what is out of this new version

The Grizzly, January 30, 2014

Sexual Misconduct Numbers in Security Report Explained • Live Feed From Ritter Stirs Debate • Colleges Soon to Consider the Impact of MOOCs • Non-Traditional Careers for Psychology Majors • School Spirit on the Rise • First Salinger Read-a-Thon Brings Holden Back to Ursinus Campus • Culture Shock: Returning to UC • Opinion: Drug Policy\u27s Punishments are Too Harsh; Netflix Streaming is Hogging our Resources • As Olympics Near, Controversy Grows • Super Bowl: Fierce Competition, Big Personalities • Winter Recap: Wrestling, Women\u27s Swimming Shinehttps://digitalcommons.ursinus.edu/grizzlynews/1895/thumbnail.jp

Characterizing the IYJ Excess Continuum Emission in T Tauri Stars

We present the first characterization of the excess continuum emission of accreting T Tauri stars between optical and near-infrared wavelengths. With nearly simultaneous spectra from 0.48 to 2.4 microns acquired with HIRES and NIRSPEC on Keck and SpeX on the IRTF, we find significant excess continuum emission throughout this region, including the I, Y, and J bands, which are usually thought to diagnose primarily photospheric emission. The IYJ excess correlates with the excess in the V band, attributed to accretion shocks in the photosphere, and the excess in the K band, attributed to dust in the inner disk near the dust sublimation radius, but it is too large to be an extension of the excess from these sources. The spectrum of the excess emission is broad and featureless, suggestive of blackbody radiation with a temperature between 2200 and 5000 K. The luminosity of the IYJ excess is comparable to the accretion luminosity inferred from modeling the blue and ultraviolet excess emission and may require reassessment of disk accretion rates. The source of the IYJ excess is unclear. In stars of low accretion rate, the size of the emitting region is consistent with cooler material surrounding small hot accretion spots in the photosphere. However, for stars with high accretion rates, the projected area is comparable to or exceeds that of the stellar surface. We suggest that at least some of the IYJ excess emission arises in the dust-free gas inside the dust sublimation radius in the disk.Comment: Accepted to ApJ, 31 pages, 21 figure