ELAV links paused Pol II to alternative polyadenylation in the Drosophila nervious system

Alternative polyadenylation (APA) has been implicated in a variety of developmental and disease processes. A particularly dramatic form of APA occurs in the developing nervous system of flies and mammals, whereby various developmental genes undergo coordinate 3' UTR extension. In Drosophila, the RNA-binding protein ELAV inhibits RNA processing at proximal polyadenylation sites, thereby fostering the formation of exceptionally long 3' UTRs. Here, we present evidence that paused Pol II promotes recruitment of ELAV to extended genes. Replacing promoters of extended genes with heterologous promoters blocks normal 3' extension in the nervous system, while extension-associated promoters can induce 3' extension in ectopic tissues expressing ELAV. Computational analyses suggest that promoter regions of extended genes tend to contain paused Pol II and associated cis-regulatory elements such as GAGA. ChIP-seq assays identify ELAV in the promoter regions of extended genes. Our study provides evidence for a regulatory link between promoter-proximal pausing and APA

Decision Processes about Condom Use among Shelter-Homeless LGBT Youth in Manhattan

Health behavior interventions based on Theory of Planned Behavior address participants' personally-held beliefs, perceived social norms, and control over the behavior. New data are always needed to “member check” participants' decision processes and inform interventions. This qualitative study investigates decision processes around condom use among 81 homeless LGBT youth ages 18–26. Findings indicated considerable endorsement of the conventional policy of always using condoms, promulgated in HIV prevention education targeting this population. Although some participants reported risk behavior in contexts of sex work, survival sex, casual encounters, open relationships, and substance use, most were aware of these risks and consistently safe in those situations. Condoms use boundaries became vulnerable in states of emotional need and negative mood. The only effect participants acknowledged of homelessness on condom use was indirect, through negative mood states. The most prevalent context of condom non-use was with long-term primary partners, a potential area of vulnerability because, of 13 participants for HIV or HCV, nine mentioned how they had been infected, and all nine believed they had acquired it from a primary partner. Findings imply programs should emphasize HIV risk potential within long-term romantic partnerships and mental health services to remediate negative mood states

The Effects of an AGN on Host Galaxy Colour and Morphology Measurements

We assess the effects of simulated active galactic nuclei (AGNs) on the colour and morphology measurements of their host galaxies. To test the morphology measurements, we select a sample of galaxies not known to host AGNs and add a series of point sources scaled to represent specified fractions of the observed V band light detected from the resulting systems; we then compare morphology measurements of the simulated systems to measurements of the original galaxies. AGN contributions >20 per cent bias most of the morphology measurements tested, though the extent of the apparent bias depends on the morphological characteristics of the original galaxies. We test colour measurements by adding to non-AGN galaxy spectra a quasar spectrum scaled to contribute specified fractions of the rest-frame B band light detected from the resulting systems. A quasar fraction of 5 per cent can move the NUV-r colour of an elliptical galaxy from the UV-optical red sequence to the green valley, and 20 per cent can move it into the blue cloud. Combining the colour and morphology results, we find that a galaxy/AGN system with an AGN contribution >20 per cent may appear bluer and more bulge-dominated than the underlying galaxy. We conclude that (1) bulge-dominated, E/S0/Sa, and early-type morphology classifications are accurate for red AGN host galaxies and may be accurate for blue host galaxies, unless the AGN manifests itself as a well-defined point source; and (2) although highly unobscured AGNs, such as the quasar used for our experiments, can significantly bias the measured colours of AGN host galaxies, it is possible to identify such systems by examining optical images of the hosts for the presence of a point source and/or measuring the level of nuclear obscuration.Comment: 18 pages, 19 figures, 1 table. Accepted for publication in MNRA

Susceptibility to Taura Syndrome Virus of Some Penaeid Shrimp Species Native to the Gulf of Mexico and the Southeastern United States

Experimental studies demonstrated that Penaeus setiferus, but not Penaeus aztecus or Penaeus duorarum, could be killed by Taura syndrome virus (TSV). However, specimens of P. setiferus that survived infection and both P. aztecus and P. duorarum at least 79 days postexposure that did not demonstrate gross signs of infection were shown to harbor virus by bioassay using Penaeus vannamei, a highly susceptible target host. Consequently, all three of those penaeids native to the southeast United States can serve as carriers or reservoir hosts of TSV without necessarily exhibiting disease. Infections in P. setiferus took longer to cause mortality than in P. vannamei and killed a smaller percentage of that host. Also, histological lesions diagnostic of TSV infection were not always evident in sectioned tissue of infected P. setiferus, and they generally were more conspicuous during Days 4–7 postexposure compared with lesions that also occurred at both earlier and later days in tissues of P. vannamei. Infections could be produced by injection, ingestion, and incorporation of the infective material into dietary brine shrimp. There appeared to be a difference in susceptibility to TSV disease by different stocks of P. setiferus, but different experiments produced conflicting evidence regarding a relationship between age and predilection to mortality. Large and small specimens of equal-aged shrimp succumbed similarly to TSV infections for both P. vannamei and P. setiferus. The nonnative species P. chinensis demonstrated a high susceptibility to experimental TSV disease

Mainstreaming education for sustainable development: Elaborating the role of position-practice systems using seven laminations of scale

The United Nations Sustainable Development Goal 4.7 proposes that Education for Sustainable Development (ESD) should be included at all levels of education, known as ‘mainstreaming’. However, there is little guidance as to how to achieve this. ESD mainstreaming demands more than simply a technical policy transfer; it also requires attention to the position-practice systems of involved agents. This article critically assesses the mainstreaming of ESD in the case of university educators in Africa who have participated in the International Training Programme on ESD in higher education. It clarifies their position-practice systems in terms of Bhaskar’s seven laminations of scale. This article therefore provides a detailed description of the ways in which agents' position-practice systems enable and constrain ESD mainstreaming. It also demonstrates that a critical realist perspective can contribute towards the understanding and achievement of transformation towards sustainability and can help to ensure the flourishing of both current and future generations

Evolution of dopant-induced helium nanoplasmas

Two-component nanoplasmas generated by strong-field ionization of doped helium nanodroplets are studied in a pump-probe experiment using few-cycle laser pulses in combination with molecular dynamics simulations. High yields of helium ions and a pronounced, droplet size-dependent resonance structure in the pump-probe transients reveal the evolution of the dopant-induced helium nanoplasma. The pump-probe dynamics is interpreted in terms of strong inner ionization by the pump pulse and resonant heating by the probe pulse which controls the final charge states detected via the frustration of electron-ion recombination

HST Morphologies of z~2 Dust Obscured Galaxies I: Power-law Sources

We present high spatial resolution optical and near-infrared imaging obtained using the ACS, WFPC2 and NICMOS cameras aboard the Hubble Space Telescope of 31 24um--bright z~2 Dust Obscured Galaxies (DOGs) identified in the Bootes Field of the NOAO Deep Wide-Field Survey. Although this subset of DOGs have mid-IR spectral energy distributions dominated by a power-law component suggestive of an AGN, all but one of the galaxies are spatially extended and not dominated by an unresolved component at rest-frame UV or optical wavelengths. The observed V-H and I-H colors of the extended components are 0.2-3 magnitudes redder than normal star-forming galaxies. All but 1 have axial ratios >0.3, making it unlikely that DOGs are composed of an edge-on star-forming disk. We model the spatially extended component of the surface brightness distributions of the DOGs with a Sersic profile and find effective radii of 1-6 kpc. This sample of DOGs is smaller than most sub-millimeter galaxies (SMGs), but larger than quiescent high-redshift galaxies. Non-parametric measures (Gini and M20) of DOG morphologies suggest that these galaxies are more dynamically relaxed than local ULIRGs. We estimate lower limits to the stellar masses of DOGs based on the rest-frame optical photometry and find that these range from ~10^(9-11) M_sun. If major mergers are the progenitors of DOGs, then these observations suggest that DOGs may represent a post-merger evolutionary stage.Comment: 23 pages, 9 figures, 6 tables, accepted to ApJ; lower limits on stellar mass revised upwards by factor of (1+z

Laser-Cluster-Interaction in a Nanoplasma-Model with Inclusion of Lowered Ionization Energies

The interaction of intense laser fields with silver and argon clusters is investigated theoretically using a modified nanoplasma model. Single pulse and double pulse excitations are considered. The influence of the dense cluster environment on the inner ionization processes is studied including the lowering of the ionization energies. There are considerable changes in the dynamics of the laser-cluster interaction. Especially, for silver clusters, the lowering of the ionization energies leads to increased yields of highly charged ions.Comment: 10 pages, 11 figure

HST Morphologies of z ~ 2 Dust-Obscured Galaxies II: Bump Sources

We present Hubble Space Telescope (HST) imaging of 22 ultra-luminous infrared galaxies (ULIRGs) at z~2 with extremely red R-[24] colors (called dust-obscured galaxies, or DOGs) which have a local maximum in their spectral energy distribution (SED) at rest-frame 1.6um associated with stellar emission. These sources, which we call "bump DOGs", have star-formation rates of 400-4000 Msun/yr and have redshifts derived from mid-IR spectra which show strong polycyclic aromatic hydrocarbon emission --- a sign of vigorous on-going star-formation. Using a uniform morphological analysis, we look for quantifiable differences between bump DOGs, power-law DOGs (Spitzer-selected ULIRGs with mid-IR SEDs dominated by a power-law and spectral features that are more typical of obscured active galactic nuclei than starbursts), sub-millimeter selected galaxies (SMGs), and other less-reddened ULIRGs from the Spitzer extragalactic First Look Survey (XFLS). Bump DOGs are larger than power-law DOGs (median Petrosian radius of 8.4 +/- 2.7 kpc vs. 5.5 +/- 2.3 kpc) and exhibit more diffuse and irregular morphologies (median M_20 of -1.08 +/- 0.05 vs. -1.48 +/- 0.05). These trends are qualitatively consistent with expectations from simulations of major mergers in which merging systems during the peak star-formation rate period evolve from M_20 = -1.0 to M_20 = -1.7. Less obscured ULIRGs (i.e., non-DOGs) tend to have more regular, centrally peaked, single-object morphologies rather than diffuse and irregular morphologies. This distinction in morphologies may imply that less obscured ULIRGs sample the merger near the end of the peak star-formation rate period. Alternatively, it may indicate that the intense star-formation in these less-obscured ULIRGs is not the result of a recent major merger.Comment: Accepted to ApJ; 22 pages, 8 Figures, 7 Table