Faint blue objects on the Hubble Deep Field North & South as possible nearby old halo white dwarfs

Using data derived from the deepest and finest angular resolution images of the universe yet acquired by astronomers at optical wavelengths using the Hubble Space Telescope (HST) in two postage-stamp sections of the sky (Williams et al. 1996a,b), plus simple geometrical and scaling arguments, we demonstrate that the faint blue population of point-source objects detected on those two fields (M\'endez et al. 1996) could actually be ancient halo white dwarfs at distances closer than about 2 kpc from the Sun. This finding has profound implications, as the mass density of the detected objects would account for about half of the missing dark matter in the Milky-Way (Bahcall and Soneira 1980), thus solving one of the most controversial issues of modern astrophysics (Trimble 1987, Ashman 1992). The existence of these faint blue objects points to a very large mass locked into ancient halo white dwarfs. Our estimate indicates that they could account for as much as half of the dark matter in our Galaxy, confirming the suggestions of the MACHO microlensing experiment (Alcock et al. 1997). Because of the importance of this discovery, deep follow-up observations with HST within the next two years would be needed to determine more accurately the kinematics (tangential motions) for these faint blue old white dwarfs.Comment: Accepted for publication on The Astrophysical Journal, Part 1. 8 pages (AAS Latex macros V4.0), 1 B&W postscript figure, 2 color postscript figure

Solitary fibrous tumors of the pleura: a clinical-pathological characterization emphasizing changes in lung function

Solitary fibrous tumors of the pleura (SFTP) represent less than 5% of all pleural tumors with a higher susceptibility for men in the sixth and seventh decades of life. Imaging and histopathological analyses indicate that these tumors have an unpredictable clinical course since larger tumors are often associated with malignancy; however, this assumption is not universal. In addition, there are no systematic descriptions of lung function in either the basal or post-surgical scenarios of SFTP patients. We describe a series of 3 patients between 4th and 5th decade of life with a benign histopathological SFTP without local recurrence in their follow-up. We also analyzed changes in lung function, emphasizing possible associations with clinical recovery

Formation of fullerenes in H-containing Planetary Nebulae

Hydrogen depleted environments are considered an essential requirement for the formation of fullerenes. The recent detection of C60 and C70 fullerenes in what was interpreted as the hydrogen-poor inner region of a post-final helium shell flash Planetary Nebula (PN) seemed to confirm this picture. Here, we present evidence that challenges the current paradigm regarding fullerene formation, showing that it can take place in circumstellar environments containing hydrogen. We report the simultaneous detection of Polycyclic Aromatic Hydrocarbons (PAHs) and fullerenes towards C-rich and H-containing PNe belonging to environments with very different chemical histories such as our own Galaxy and the Small Magellanic Cloud. We suggest that PAHs and fullerenes may be formed by the photochemical processing of hydrogenated amorphous carbon. These observations suggest that modifications may be needed to our current understanding of the chemistry of large organic molecules as well as the chemical processing in space.Comment: accepted for publication in The Astrophysical Journal Letters (14 pages, 4 figures and 1 Table). Replaced version with slight changes in the abstrac

Adapting Clinical Services To Accommodate Needs of Refugee Populations

The diversity of the refugee population in the United States requires practicing psychologists to respond by adapting clinical services to meet their mental health needs. However, the available literature on culturally adapted treatments is only a first step in guiding the process for adapting clinical services. This paper describes our experiences with designing and adapting a variety of clinical services for youth and families with refugee status. Guided by Sue\u27s (2006) tenets for culturally competent service delivery, we discuss a therapeutic model of tiered service delivery used to deliver preventative services and treatment to refugee youth and adults. We discuss how we adapted treatments to help overcome access barriers to mental health treatment, and we provide specific examples of how existing treatments were used with refugee populations. In addition, we discuss information and approaches for how practicing psychologists can develop additional skills for working with refugee populations. We conclude by focusing on the need for our field to work toward improving access to mental health treatment for refugee youth and families and developing evidence-based treatments for this population

Longitudinal Professional Identity Development Amongst Medical Students

Abstract Title: Longitudinal Professional Identity Development Amongst Medical Students Background: Professional development is a core competency for medical student education. A standardized model for assessment of student longitudinal professional identity development will allow medical schools to better implement interventions. Methods: To assess professional development at a large, Midwest, allopathic medical school, a survey with seven statements regarding professional development was created. The statements encompassed domains of mentorship, communication skills, professionalism, and innovation and asked students to rank each statement from 1-5 (1 - highly deficient, 5 - highly proficient). The online, anonymous survey was emailed to all students (n = 1154) over a 2 month time period. Results: 319 (27.6%) surveys were completed. Responses between year 1-2 and year 3-4 showed a unanimous increase in average proficiency across all 7 statements. Year 3-4 had a significant increase in overall proficiency (p Conclusion: Although professional identity development follows an overall upward trend, year 3 is a vulnerable period for professional identity development. While increased accessibility to advising is needed in all four years, it is even more necessary in year 3. The power of the study is limited by the number of responses

Abundances in planetary nebulae: NGC1535, NGC6629, He2-108, and Tc1

The aim of the paper is to determine abundances in a group of PNe with uniform morphology. The PNe discussed are circular excited by rather low-temperature central stars. The relation between abundance and evolution is discussed. The mid-infrared spectra of NGC1535, NGC6629, He2-108 and Tc1 taken with the Spitzer Space Telescope are presented. These spectra are combined with IUE and visual spectra to obtain complete extinction-corrected spectra from which the abundances are determined. These abundances are more accurate for several reasons, the most important is that the inclusion of the far infrared spectra increases the number of observed ions and makes it possible to include the nebular temperature gradient in the abundance calculation. The abundances of these PNe are compared to those found in five other PNe of similar properties and are further compared with predictions of evolutionary models. From this comparison we conclude that these PNe originated from low mass stars, probably between 1 and 2.5 solar masses and at present have core masses between 0.56 and 0.63 solar masses. A consistent description of the evolution of this class of PNe is found that agrees with the predictions of the present nebular abundances, the individual masses and the luminosities of these PNe. The distances to these nebulae can be found as well.Comment: 17 pages, 18 tables, 1 figure, Accepted for publication in A&

The effect of a startle-eliciting device on the foraging success of individual harbor seals (Phoca vitulina)

Pinniped predation on commercially and ecologically important prey has been a source of conflict for centuries. In the Salish Sea, harbor seals (Phoca vitulina) are suspected of impeding the recovery of culturally and ecologically critical Pacific salmon (Oncorhynchus spp.). In Fall 2020, a novel deterrent called Targeted Acoustic Startle Technology (TAST) was deployed at Whatcom Creek to deter harbor seals from preying on fall runs of hatchery chum (O. keta) and Chinook (O. tshawytscha) salmon in Bellingham, Washington, USA. Field observations were conducted in 2020 to compare the presence and foraging success of individual harbor seals across sound exposure (TAST-on) and control (TAST-off) conditions. Observations conducted the previous (2019) and following (2021) years were used to compare the effects observed in 2020 to two control years. Using photo-identification, individual seals were associated with foraging successes across all 3 years of the study. Generalized linear mixed models showed a significant 45.6% reduction in the duration (min) individuals remained at the creek with TAST on, and a significant 43.8% reduction in the overall foraging success of individuals. However, the observed effect of TAST varied across individual seals. Seals that were observed regularly within one season were more likely to return the year after, regardless of TAST treatment. Generalized linear models showed interannual variation in the number of seals present and salmon consumed. However, the effect of TAST in 2020 was greater than the observed variation across years. Our analyses suggest TAST can be an effective tool for managing pinniped predation, although alternate strategies such as deploying TAST longer-term and using multi-unit setups to increase coverage could help strengthen its effects. Future studies should further examine the individual variability found in this study.Peer reviewe

Regularizing made-to-measure particle models of galaxies

Made-to-measure methods such as the parallel code NMAGIC are powerful tools to build galaxy models reproducing observational data. They work by adapting the particle weights in an N-body system until the target observables are well matched. Here we introduce a moving prior regularization (MPR) method for such particle models. It is based on determining from the particles a distribution of priors in phase-space, which are updated in parallel with the weight adaptation. This method allows one to construct smooth models from noisy data without erasing global phase-space gradients. We first apply MPR to a spherical system for which the distribution function can in theory be uniquely recovered from idealized data. We show that NMAGIC with MPR indeed converges to the true solution with very good accuracy, independent of the initial particle model. Compared to the standard weight entropy regularization, biases in the anisotropy structure are removed and local fluctuations in the intrinsic distribution function are reduced. We then investigate how the uncertainties in the inferred dynamical structure increase with less complete and noisier kinematic data, and how the dependence on the initial particle model also increases. Finally, we apply the MPR technique to the two intermediate-luminosity elliptical galaxies NGC 4697 and NGC 3379, obtaining smoother dynamical models in luminous and dark matter potentials.Comment: 16 pages, 15 figures, 2 tables. Accepted for publication in MNRA