Rotation and Macroturbulence in Metal-poor Field Red Giant and Red Horizontal Branch Stars

We report the results for rotational velocities, Vrot sin i, and macroturbulence dispersion, zeta(RT), for 12 metal-poor field red giant branch stars and 7 metal-poor field red horizontal branch stars. The results are based on Fourier transform analyses of absorption line profiles from high-resolution (R ~ 120,000), high-S/N (~ 215 per pixel) spectra obtained with the Gecko spectrograph at CFHT. We find that the zeta(RT) values for the metal-poor RGB stars are very similar to those for metal-rich disk giants studied earlier by Gray and his collaborators. Six of the RGB stars have small rotational values, less than 2.0 km/sec, while five show significant rotation, over 3 km/sec. The fraction of rapidly rotating RHB stars is somewhat lower than found among BHB stars. We devise two empirical methods to translate the line-broadening results obtained by Carney et al. (2003, 2008) into Vrot sin i for all the RGB and RHB stars they studied. Binning the RGB stars by luminosity, we find that most metal-poor field RGB stars show no detectable sign, on average, of rotation. However, the most luminous stars, with M(V) <= -1.5, do show net rotation, with mean values of 2 to 4 km/sec, depending on the algorithm employed, and these stars also show signs of radial velocity jitter and mass loss.Comment: accepted for publication in the Astronomical Journa

Stars of extragalactic origin in the solar neighborhood

We computed the spatial velocities and the galactic orbital elements using Hipparcos data for 77 nearest main-sequence F-G-stars with published the iron, magnesium, and europium abundances determined from high dispersion spectra and with the ages estimated from theoretical isochrones. A comparison with the orbital elements of the globular clusters that are known was accreted by our Galaxy in the past reveals stars of extragalactic origin. We show that the relative elemental abundance ratios of r- and \alpha- elements in all the accreted stars differ sharply from those in the stars that are genetically associated with the Galaxy. According to current theoretical models, europium is produced mainly in low mass Type II supernovae (SNe II), while magnesium is synthesized in larger amounts in high mass SN II progenitors. Since all the old accreted stars of our sample exhibit a significant Eu overabundance relative to Mg, we conclude that the maximum masses of the SNII progenitors outside the Galaxy were much lower than those inside it are. On the other hand, only a small number of young accreted stars exhibit low negative ratios $[Eu/Mg] < 0$. The delay of primordial star formation burst and the explosions of high mass SNe II in a relatively small part of extragalactic space can explain this situation. We provide evidence that the interstellar medium was weakly mixed at the early evolutionary stages of the Galaxy formed from a single proto-galactic cloud and that the maximum mass of the SN II progenitors increased in it with time simultaneously with the increase in mean metallicity.Comment: Accepted for 2004, Astronomy Letters, Vol. 30, No. 3, P.148-158 15 pages, 3 figure

Profile of the most common complaints for five health professions in Australia

© 2019 AHHA. Objective: The aims of this study were to profile the most common complaints and to examine whether any demographic factors are associated with receiving a complaint for five health professions in Australia. Methods: A national cohort study was conducted for all complaints received for medicine, nursing/midwifery, dentistry, pharmacy and psychology from 1 July 2012 to 31 December 2013 (18 months). Data were collected from the Australian Health Practitioner Regulation Agency (AHPRA), the New South Wales (NSW) Health Professional Councils' Authority and the NSW Health Care Complaints Commission. The frequency and risk of complaints were summarised for the five professions and by demographic information. Results: There were 545 283 practitioners registered with AHPRA between 1 July 2012 and 31 December 2013, consisting of 20 935 dentists, 101 066 medical practitioners, 363 040 nurses/midwives, 28 370 pharmacists and 31 872 psychologists. During the study period there were 12 616 complaints, corresponding to an annual rate of 1.5 per 100 practitioners. Complaints were most common for doctors and dentists (5% per annum per practitioner) and least common for nurses/midwives (0.5% per annum per practitioner). Sex (P < 0.01), age (P < 0.01) and country of birth (P < 0.01) were all associated with risk of complaint. The most common complaints were clinical care (44% of all complaints), medication (10%) and health impairment of the practitioner (8%). Types of complaints varied by profession, sex and age. Conclusions: The risk of a complaint is low, but varies by profession and demographics. The types of complaints also vary by profession and demographics. Differences between professions is most likely driven by their different work tasks and work environments. What is already known on this subject?: Although complaints are summarised annually from state and national health regulators, no overall national summary of complaints across professions exists. Thus, it is difficult to examine which complaints are most common, how professions differ from each other or what factors may be associated with risk and type of complaint. Previous studies have primarily focused on a single profession, such as medicine, where, for example, the number of prior complaints, sex, doctor speciality and age have been found to be associated with recurrent complaints. What does this paper add?: This paper is the first of this kind to provide a national summary of all complaints from five of the most common health professions in Australia. We found that regardless of profession, men were at least twice as likely to have a complaint made against them than women. We also found that the types of complaint differed between men and women. There were similarities across professions for the most common types of complaints, but clear differences between professions were also noted. Not surprising, clinical care was typically the most common type of complaint for the five professions, but somewhat surprising was the inclusion of health impairment as one of the most common types of complaints. What are the implications for practitioners?: Identifying the most common complaints, and the factors associated with these, may assist practitioners to understand their risk(s) of complaint and could potentially assist educators and regulators develop education programs that help reduce complaints

Blue Horizontal Branch Stars in Old, Metal-Rich Stellar Systems

Twenty years ago, Burstein et al. (1984)suggested that strong CN and Hbeta absorption meant younger ages among globular clusters in the Andromeda galaxy (M31), unless blue stars above the main-sequence turnoff or on the horizontal branch were uncommonly prominent. Here we test these suggestions by fitting the detailed mid-ultraviolet (2280-3120A) and optical (3850-4750A) spectra of one moderately metal-rich M31 globular cluster, G1. We explore the effects of a wide range of non-solar temperatures and abundance ratios, by combining a small set of theoretical stellar spectra like those of Peterson et al. (2001) that were calculated using extensively updated atomic-line constants. To match the mid-UV fluxes of G1, we find that hot components with Teff >= 8000K must be included. We obtain a very good fit with cool and hot blue horizontal branch (BHB) stars, but less satisfactory fits for blue straggler stars, those hotter than the main-sequence turnoff. The G1 color-magnitude diagram does show cool BHB stars, and the color of its giant branch supports the metallicity of one-sixth the solar value that we deduce. The turnoff temperature of the best-fit model is consistent with that of turnoff stars in galactic globular clusters and the field halo, indicating G1 is comparably old. Because metal-rich cool BHB and extremely blue HB stars have now been found within our own Galaxy, we suggest that these hot horizontal-branch stars be considered in fitting spectra of metal-rich populations such as the Andromeda globular clusters, to avoid possible underestimates of their ages. We plan to make the relevant spectral calculations available as part of our Hubble Treasury Program

Once and Future Gulf of Mexico Ecosystem: Restoration Recommendations of an Expert Working Group

The Deepwater Horizon (DWH) well blowout released more petroleum hydrocarbons into the marine environment than any previous U.S. oil spill (4.9 million barrels), fouling marine life, damaging deep sea and shoreline habitats and causing closures of economically valuable fisheries in the Gulf of Mexico. A suite of pollutants—liquid and gaseous petroleum compounds plus chemical dispersants—poured into ecosystems that had already been stressed by overfishing, development and global climate change. Beyond the direct effects that were captured in dramatic photographs of oiled birds in the media, it is likely that there are subtle, delayed, indirect and potentially synergistic impacts of these widely dispersed, highly bioavailable and toxic hydrocarbons and chemical dispersants on marine life from pelicans to salt marsh grasses and to deep-sea animals. As tragic as the DWH blowout was, it has stimulated public interest in protecting this economically, socially and environmentally critical region. The 2010 Mabus Report, commissioned by President Barack Obama and written by the secretary of the Navy, provides a blueprint for restoring the Gulf that is bold, visionary and strategic. It is clear that we need not only to repair the damage left behind by the oil but also to go well beyond that to restore the anthropogenically stressed and declining Gulf ecosystems to prosperity-sustaining levels of historic productivity. For this report, we assembled a team of leading scientists with expertise in coastal and marine ecosystems and with experience in their restoration to identify strategies and specific actions that will revitalize and sustain the Gulf coastal economy. Because the DWH spill intervened in ecosystems that are intimately interconnected and already under stress, and will remain stressed from global climate change, we argue that restoration of the Gulf must go beyond the traditional "in-place, in-kind" restoration approach that targets specific damaged habitats or species. A sustainable restoration of the Gulf of Mexico after DWH must: 1. Recognize that ecosystem resilience has been compromised by multiple human interventions predating the DWH spill; 2. Acknowledge that significant future environmental change is inevitable and must be factored into restoration plans and actions for them to be durable; 3. Treat the Gulf as a complex and interconnected network of ecosystems from shoreline to deep sea; and 4. Recognize that human and ecosystem productivity in the Gulf are interdependent, and that human needs from and effects on the Gulf must be integral to restoration planning. With these principles in mind, the authors provide the scientific basis for a sustainable restoration program along three themes: 1. Assess and repair damage from DWH and other stresses on the Gulf; 2. Protect existing habitats and populations; and 3. Integrate sustainable human use with ecological processes in the Gulf of Mexico. Under these themes, 15 historically informed, adaptive, ecosystem-based restoration actions are presented to recover Gulf resources and rebuild the resilience of its ecosystem. The vision that guides our recommendations fundamentally imbeds the restoration actions within the context of the changing environment so as to achieve resilience of resources, human communities and the economy into the indefinite future

The Multiple Origin of Blue Straggler Stars: Theory vs. Observations

In this chapter we review the various suggested channels for the formation and evolution of blue straggler stars (BSSs) in different environments and their observational predictions. These include mass transfer during binary stellar evolution - case A/B/C and D (wind Roche-lobe overflow) mass transfer, stellar collisions during single and binary encounters in dense stellar cluster, and coupled dynamical and stellar evolution of triple systems. We also explore the importance of the BSS and binary dynamics in stellar clusters. We review the various observed properties of BSSs in different environments (halo and bulge BSSs, BSSs in globular clusters and BSSs in old open clusters), and compare the current observations with the theoretical predictions for BSS formation. We try to constrain the likely progenitors and processes that play a role in the formation of BSSs and their evolution. We find that multiple channels of BSS formation are likely to take part in producing the observed BSSs, and we point out the strengths and weaknesses of each the formation channel in respect to the observational constraints. Finally we point out directions to further explore the origin of BSS, and highlight eclipsing binary BSSs as important observational tool.Comment: Chapter 11, in Ecology of Blue Straggler Stars, H.M.J. Boffin, G. Carraro & G. Beccari (Eds), Astrophysics and Space Science Library, Springe

Substance use and depressive and anxiety symptoms among out-of-school adolescent girls and young women in Cape Town, South Africa

Background. There is a high prevalence of substance use among youth in South Africa (SA), and adolescent girls and young women (AGYW) experience high rates of depression and anxiety. Substance use behaviours and mental health are associated with other public health problems among AGYW such as HIV and unintended pregnancy. Therefore, understanding the relationship between substance use and mental health is imperative to improve AGYW’s health.Objectives. To examine the association between heavy drinking, marijuana, methamphetamine and methaqualone (Mandrax) use and depressive and anxiety symptoms among AGYW aged 16 - 19 years who have dropped out of school in Cape Town, SA.Methods. Data for this report come from the baseline data of 500 participants of an ongoing cluster-randomised trial assessing the efficacy of a young woman-focused intervention to reduce substance use and HIV risk. After AGYW consented/assented to participate, they completed a urine drug screen and a baseline questionnaire.Results. Logistic and negative binomial regressions, controlling for clustering at the neighbourhood level, revealed that frequency of depressive symptoms was significantly and positively related to a positive drug screen for Mandrax (β=0.07; p=0.03). All other associations between the frequency of depressive symptoms and substance use were not statistically significant (ps&gt;0.05). The associations between frequency of anxiety symptoms and substance use were not statistically significant (ps&gt;0.05).Conclusions. Our findings highlight the need to address substance use, especially Mandrax use and its associated risk, and depression in an integrated, youth-friendly setting

Mandrax use, sexual risk, and opportunities for pre-exposure prophylaxis among out-of-school adolescent girls and young women in Cape Town, South Africa

Background. In South Africa (SA), adolescent girls and young women (AGYW) aged 15 - 24 years account for nearly 25% of all new HIV infections in the country. The intersection of substance use and sexual risk continues to drive the HIV epidemic among AGYW. For example, methaqualone, also known as Mandrax, has sedative effects that may affect women’s ability to negotiate condom use during sex, refuse sex without a condom, or consent to sex, thereby increasing their risk for HIV. Consequently, it is critical to understand how Mandrax use affects HIV risk among AGYW and to assess awareness of and willingness to use biomedical HIV prevention methods, such as pre-exposure prophylaxis (PrEP), among AGYW who use Mandrax.Objectives. To examine the role of Mandrax use in sexual behaviours and investigate the extent to which AGYW who use Mandrax are aware of and willing to initiate PrEP.Methods. Data for this report were derived from baseline and 6-month follow-up data provided by 500 AGYW participating in a cluster-randomised trial assessing the efficacy of a young woman-focused intervention to reduce substance use and HIV risk. AGYW who self-identified as black African or coloured, reported using substances, reported condomless sex in the past 3 months, and had discontinued school early were recruited from 24 community clusters across Cape Town, SA. Following consent/assent, participants provided biological specimens to test for recent drug use (including Mandrax) and completed the self-report questionnaire.Results. Logistic regression analysis revealed that the AGYW who had a positive test result for Mandrax use were less likely to use a condom with their main partner (p=0.01), and almost three times more likely to use alcohol and/or other drugs before or during their last act of sexual intercourse (p&lt;0.001), compared with the AGYW who had a negative Mandrax test result. Mandrax use was not significantly related to PrEP awareness (p&gt;0.10) or willingness to use PrEP (p&gt;0.10), but 70% of AGYW who used Mandrax were willing to initiate PrEP.Conclusion. The study findings highlight how Mandrax use may contribute to HIV risk among SA AGYW. Key decision-makers should consider incorporating substance use prevention efforts into existing HIV reduction programmes and equip youth-friendly clinics with the resources to identify AGYW who use Mandrax and offer them PrEP

Distances and ages of globular clusters using Hipparcos parallaxes of local subdwarfs

We discuss the impact of Population II and Globular Cluster (GCs) stars on the derivation of the age of the Universe, and on the study of the formation and early evolution of galaxies, our own in particular. The long-standing problem of the actual distance scale to Population II stars and GCs is addressed, and a variety of different methods commonly used to derive distances to Population II stars are briefly reviewed. Emphasis is given to the discussion of distances and ages for GCs derived using Hipparcos parallaxes of local subdwarfs. Results obtained by different authors are slightly different, depending on different assumptions about metallicity scale, reddenings, and corrections for undetected binaries. These and other uncertainties present in the method are discussed. Finally, we outline progress expected in the near future.Comment: Invited review article to appear in: `Post-Hipparcos Cosmic Candles', A. Heck & F. Caputo (Eds), Kluwer Academic Publ., Dordrecht, in press. 22 pages including 3 tables and 2 postscript figures, uses Kluwer's crckapb.sty LaTeX style file, enclose

Communications Biophysics

Contains reports on four research projects.National Institutes of Health (Grant 5 PO1 GM14940-05)National Aeronautics and Space Administration (Grant NGL 22-009-304)National Institutes of Health (Grant 5 TO1 GM01555-05)Boston City Hospital Purchase Order 10656B-D Electrodyne Division, Becton Dickinson and Compan