A CNO Dichotomy among O2 Giant Spectra in the Magellanic Clouds

From a survey of the 3400 Å region in the earliest O-type spectra, we have found that two of the four O2 giants observed in the Large Magellanic Cloud have O IV lines there that are stronger than the N IV lines, while the other two have the opposite. A Small Magellanic Cloud counterpart also has N IV stronger than O IV. Inspection of the blue spectra of these stars shows that the former pair have weaker N lines in all ionization states (III, IV, and V) present as well as lines of C IV λ4658, while the latter three have stronger N lines and greater He/H. Space ultraviolet observations of two of the N-strong stars show N V wind profiles substantially stronger than those of C IV, while in the N-weak stars the C IV features are equal to or stronger than the N V. The N-strong stars are now reclassified as ON2 III(f*), newly defining that category. These characteristics strongly suggest a larger fraction of processed material in the atmospheres of the ON2 stars, which we confirm by modeling the optical spectra. In the context of current models, it is in turn implied that the ON2 stars are in a more advanced evolutionary state than the others, and/or that they had higher initial rotational velocities. The recent formulation of the effects of rotation on massive stellar evolution introduces an additional fundamental parameter, which the CNO abundances are in principle able to constrain. We present some illustrative comparisons with current Geneva evolutionary models for rotating massive stars. It is possible that these very hot, nitrogen-rich objects are products of homogeneous evolution. Our results will provide motivation for further physical modeling of the atmospheres and evolutionary histories of the most massive hot stars.Fil: Walborn, Nolan Revere. Space Telescope Science Institute; Estados UnidosFil: Morrell, Nidia Irene. Las campanas observatory; ChileFil: Howarth, Ian D.. University College London; Estados UnidosFil: Crowther, Paul A.. University of Sheffield; Reino UnidoFil: Lennon, Daniel J.. Isaac Newton Group of Telescopes; EspañaFil: Massey, Philip. Lowell Observatory; Estados UnidosFil: Arias, Julia Ines. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentin

Metamodels to Bridge the Gap Between Modeling and Decision Support

Insights from process-based models are a mainstay of many groundwater investigations; however, long runtimes often preclude their use in the decision-making process. Screening-level predictions are often needed in areas lacking time or funding for rigorous process-based modeling. The U.S. Geological Survey (USGS) Groundwater Resources and National Water Quality Assessment Programs are addressing these issues by evaluating the “metamodel” to bridge these gaps. A metamodel is a statistical model founded on a computationally expensive model. Although faster, the question remains: Can a statistical model provide similar insights to a numerical model with faster results

The Welfare of Animals Transported From Ireland to Italy.

End of Project ReportThe overall objective of the present study was to investigate the physiological, haematological and immunological responses of weanling bulls transported to Italy under present EU legislation and to evaluate the implications in terms of animal welfare

A Period and a Prediction for the Of?p Spectrum Alternator HD 191612

The observational picture of the enigmatic O-type spectrum variable HD191612 has been sharpened substantially. A symmetrical, low-amplitude light curve with a period near 540 d has recently been reported from Hipparcos photometry. This period satisfies all of the spectroscopy since at least 1982, including extensive new observations during 2003 and 2004, and it has predicted the next transition during September--October 2004. Measurements of the H alpha equivalent width reveal a sharp emission peak in the phase diagram, in contrast to the apparently sinusoidal light curve. The He II absorption-line strength is essentially constant, while He I varies strongly, possibly filled in by emission in the O6 state, thus producing the apparent spectral-type variations. The O8 state appears to be the "normal" one. Two intermediate O7 observations have been obtained, which fall at the expected phases, but these are the only modern observations of the transitions so far. The period is too long for rotation or pulsation; although there is no direct evidence as yet for a companion, a model in which tidally induced oscillations drive an enhanced wind near periastron of an eccentric orbit appears promising. Further observations during the now predictable transitions may provide a critical test. Ultraviolet and X-ray observations during both states will likely also prove illuminating.Comment: 7 pages, 3 figures, 1 table; scheduled for the 2004 December 10 issue of ApJL, Vol. 617, No. 1. ApJ

Effects of Pre-Journey Fasting on the Physiological Responses of Young Cattle to 8-hour Road Transport.

End of Project ReportThe present study evaluated the effects of fasting animals for 8 hours prior to an 8-hour road journey and their ability to cope with the stress of transport.There was no significant difference in rectal body temperature, pre and post transport and there were no significant differences in liveweight among treatments on days 0 (pre-transport), 1, 4 and 10 (post-transport). Bulls (230kg) undergoing an 8-h transportation at stocking densities of 0.82 m2 /animal showed physiological and haematological responses that were within normal referenced ranges. Animals that were fasted for 8-hours and then transported lost 9.4% bodyweight following the 8-hour journey, while non-fasted and transported animals (NF+T) lost 7.2%. The control animals remaining at grass and non-fasted (NF+G) gained 2%. The animals that were fasted continuously and not transported (F+F) and the non-fasted control animals that were fasted for 8 hours (NF+F) lost 6.1% and 6.2% respectively. There was no significant change in globulin, glucose, urea, haemoglobin, beta-hydroxy butyrate, fibrinogen concentrations, haematocrit and monocyte percentages, monocyte and red blood cell numbers, platelet numbers among treatments prior to or after transport. The % lymphocytes were reduced in the fasted and non-fasted transported animals and post-transport and there was no significant change in lymphocyte numbers. The % of neutrophils and the number of neutrophils were significantly increased in the fasted and non-fasted transported animals. Baseline protein concentrations were significantly lower in the non-fasted and transported and nonfasted then fasted treatments initially. Following transport, protein concentrations were significantly higher in the fasted and transported treatment compared with the non-fasted animals at grass. White blood cell (WBC) numbers were not significantly different prior to transport. Following transport, the WBC numbers were significantly higher in the fasted and transported treatment compared with the non-fasted at grass, fasted and then fasted, and the non-fasted and fasted treatments. Albumin concentrations were significantly higher following transport in the F+T treatment compared with the NF+G, F+F, and NF+F treatments and the NF+T treatment had significantly lower albumin levels than the F+T and NF+F treatments. Haptoglobin concentrations were not significantly different prior to transport. Following transport, haptoglobin concentrations were significantly higher in the F+T compared with the NF+G treatment. Lactate concentrations were significantly higher in the F+T and NF+T compared with the NF+G, F+F, and NF+F treatments following transport. In conclusion, from the physiological and haematological measurements, an 8 hour journey time, even without access to feed for 8 hours prior to transport did not impact negatively on animal welfare

Neurological, Cognitive, and Psychological Findings Among Survivors of Ebola Virus Disease From the 1995 Ebola Outbreak in Kikwit, Democratic Republic of Congo: A Cross-sectional Study.

BackgroundClinical sequelae of Ebola virus disease (EVD) have not been described more than 3 years postoutbreak. We examined survivors and close contacts from the 1995 Ebola outbreak in Kikwit, Democratic Republic of Congo (DRC), and determined prevalence of abnormal neurological, cognitive, and psychological findings and their association with EVD survivorship.MethodsFrom August to September 2017, we conducted a cross-sectional study in Kikwit, DRC. Over 2 decades after the EVD outbreak, we recruited EVD survivors and close contacts from the outbreak to undergo physical examination and culturally adapted versions of the Folstein mini-mental status exam (MMSE) and Goldberg anxiety and depression scale (GADS). We estimated the strength of relationships between EVD survivorship and health outcomes using linear regression models by comparing survivors versus close contacts, adjusting for age, sex, educational level, marital status, and healthcare worker status.ResultsWe enrolled 20 EVD survivors and 187 close contacts. Among the 20 EVD survivors, 4 (20%) reported at least 1 abnormal neurological symptom, and 3 (15%) had an abnormal neurological examination. Among the 187 close contacts, 14 (11%) reported at least 1 abnormal neurologic symptom, and 9 (5%) had an abnormal neurological examination. EVD survivors had lower mean MMSE and higher mean GADS scores as compared to close contacts (MMSE: adjusted coefficient: -1.85; 95% confidence interval [CI]: -3.63, -0.07; GADS: adjusted coefficient: 3.91; 95% CI: 1.76, 6.04).ConclusionsEVD survivors can have lower cognitive scores and more symptoms of depression and anxiety than close contacts more than 2 decades after Ebola virus outbreaks

Asymmetry and Inequity in the Inheritance of a Bacterial Adhesive

Pseudomonas aeruginosa is an opportunistic human pathogen that forms biofilm infections in a wide variety of contexts. Biofilms initiate when bacteria attach to a surface, which triggers changes in gene expression leading to the biofilm phenotype.Wehave previously shown, for the P. aeruginosa lab strain PAO1, that the self-produced polymer Psl is the most dominant adhesive for attachment to the surface but that another self-produced polymer, Pel, controls the geometry of attachment of these rod-shaped bacteria—strains that make Psl but not Pel are permanently attached to the surface but adhere at only one end (tilting up off the surface), whereas wild-type bacteria that make both Psl and Pel are permanently attached and lie down flat with very little or no tilting (Cooley et al 2013 Soft Matter 9 3871–6). Here we show that the change in attachment geometry reflects a change in the distribution of Psl on the bacterial cell surface. Bacteria that make Psl and Pel have Psl evenly coating the surface, whereas bacteria that make only Psl have Psl concentrated at only one end.Weshow that Psl can act as an inheritable, epigenetic factor. Rod-shaped P. aeruginosa grows lengthwise and divides across the middle.Wefind that asymmetry in the distribution of Psl on a parent cell is reflected in asymmetry between siblings in their attachment to the surface. Thus, Pel not only promotes P. aeruginosa lying downWe thank Professor Matthew Parsek (University of Washington, Seattle) for his generous gift of bacterial PAO1 strains.Wealso thank Professor Marvin Whiteley (University of Texas at Austin) forWTandΔpsl polysaccharide preparations. SIM imaging (for figure 1) was performed in the Microscopy Core Facility within the Institute for Cellular and Molecular Biology atUTAustin, with the assistance of Julie Hayes. This work was funded by startup funds fromUTAustin and a gift from ExxonMobil to VDG, and by a grant from the Human Frontiers Science Program (HFSP RGY0081/2012-GORDON).Center for Nonlinear Dynamic

Fermi-LAT Observations and A Broadband Study of Supernova Remnant CTB 109

CTB 109 (G109.1-1.0) is a Galactic supernova remnant (SNR) with a hemispherical shell morphology in X-rays and in the radio band. In this work we report the detection of {\gamma}-ray emission coincident with CTB 109, using 37 months of data from the Large Area Telescope on board the Fermi Gamma-ray Space Telescope. We study the broadband characteristics of the remnant using a model that includes hydrodynamics, efficient cosmic ray acceleration, nonthermal emission and a self-consistent calculation of the X-ray thermal emission. We find that the observations can be successfully fit with two distinct parameter sets, one where the {\gamma}-ray emission is produced primarily by leptons accelerated at the SNR forward shock and the other where {\gamma}-rays produced by forward shock accelerated cosmic-ray ions dominate the high-energy emission. Consideration of thermal X-ray emission introduces a novel element to the broadband fitting process, and while it does not rule out either the leptonic or the hadronic scenarios, it constrains the parameter sets required by the model to fit the observations. Moreover, the model which best fits the thermal and nonthermal emission observations is an intermediate case, where both radiation from accelerated electrons and hadrons contribute almost equally to the {\gamma}-ray flux observed.Comment: 10 pages, 6 figures. Accepted for publication in Ap