207 research outputs found
A Clinical and Laboratory Study of Several Infective Fevers with Particular Reference to Scarlet Fever
Beyond the Brim of the Hat: Kinematics of Globular Clusters out to Large Radius in the Sombrero Galaxy
We have obtained radial velocity measurements for 51 new globular clusters
around the Sombrero galaxy. These measurements were obtained using
spectroscopic observations from the AAOmega spectrograph on the
Anglo-Australian Telescope and the Hydra spectrograph at WIYN. Combined with
our own past measurements and velocity measurements obtained from the
literature we have constructed a large database of radial velocities that
contains a total of 360 confirmed globular clusters. Previous studies' analyses
of the kinematics and mass profile of the Sombrero globular cluster system have
been constrained to the inner ~9' (~24 kpc or ~5 effective radii), but our new
measurements have increased the radial coverage of the data, allowing us to
determine the kinematic properties of M104 out to ~15' (~41 kpc or ~9 effective
radii). We use our set of radial velocities to study the GC system kinematics
and to determine the mass profile and V-band mass-to-light profile of the
galaxy. We find that the V-band mass-to-light ratio increases from 4.5 at the
center to a value of 20.9 at 41 kpc (~9 effective radii or 15'), which implies
that the dark matter halo extends to the edge of our available data set. We
compare our mass profile at 20 kpc (~4 effective radii or ~7.4') to the mass
computed from x-ray data and find good agreement. We also use our data to look
for rotation in the globular cluster system as a whole, as well as in the red
and blue subpopulations. We find no evidence for significant rotation in any of
these samples.Comment: Accepted for publication in the Astronomical Journal; 23 pages, 14
figures, and 2 table
Sodium content as a predictor of the advanced evolution of globular cluster stars
The asymptotic giant branch (AGB) phase is the final stage of nuclear burning
for low-mass stars. Although Milky Way globular clusters are now known to
harbour (at least) two generations of stars they still provide relatively
homogeneous samples of stars that are used to constrain stellar evolution
theory. It is predicted by stellar models that the majority of cluster stars
with masses around the current turn-off mass (that is, the mass of the stars
that are currently leaving the main sequence phase) will evolve through the AGB
phase. Here we report that all of the second-generation stars in the globular
cluster NGC 6752 -- 70 per cent of the cluster population -- fail to reach the
AGB phase. Through spectroscopic abundance measurements, we found that every
AGB star in our sample has a low sodium abundance, indicating that they are
exclusively first-generation stars. This implies that many clusters cannot
reliably be used for star counts to test stellar evolution timescales if the
AGB population is included. We have no clear explanation for this observation.Comment: Published in Nature (online 29 May 2013, hard copy 13 June), 12
pages, 3 figures + supplementary information sectio
Metagenomic analysis of DNA viruses with targeted sequence capture of canine lobular orbital adenomas and normal conjunctiva
Our study aims are: (1) to evaluate phenotypically normal canine conjunctival and orbital tissue and tissue from canine lobular orbital adenomas (CLOAs) for the presence of viral genomic material and (2) phylogenetically classify detected DNA viruses to determine if a DNA virus is associated with CLOAs. A total of 31 formalin fixed paraffin embedded CLOA tissue samples, 4 papillomas or sarcoid, and 10 fresh clinically normal conjunctival tissues were included in this study. Genomic DNA was isolated from all samples and sequencing libraries were prepared. The libraries were molecularly indexed and pooled and viral DNA was enriched via targeted sequence capture utilizing ViroCap. The libraries were sequenced on the Illumina HiSeq platform and compared to known viral DNA reference genomes to identify viral DNA. Carnivore parvovirus was identified in 6.4% and 20% of CLOA tissue and normal conjunctival samples, respectively. This study showed that conjunctival tissue from healthy dogs and CLOAs uncommonly harbor DNA viruses, and no DNA virus was associated with these tumors. Further studies are needed to evaluate the etiologic cause of CLOAs
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Short and long-term lifestyle coaching approaches used to address diverse participant barriers to weight loss and physical activity adherence
Background: Individual barriers to weight loss and physical activity goals in the Diabetes Prevention Program, a randomized trial with 3.2 years average treatment duration, have not been previously reported. Evaluating barriers and the lifestyle coaching approaches used to improve adherence in a large, diverse participant cohort can inform dissemination efforts. Methods: Lifestyle coaches documented barriers and approaches after each session (mean session attendance = 50.3 ± 21.8). Subjects were 1076 intensive lifestyle participants (mean age = 50.6 years; mean BMI = 33.9 kg/m2; 68% female, 48% non-Caucasian). Barriers and approaches used to improve adherence were ranked by the percentage of the cohort for whom they applied. Barrier groupings were also analyzed in relation to baseline demographic characteristics. Results: Top weight loss barriers reported were problems with self-monitoring (58%); social cues (58%); holidays (54%); low activity (48%); and internal cues (thought/mood) (44%). Top activity barriers were holidays (51%); time management (50%); internal cues (30%); illness (29%), and motivation (26%). The percentage of the cohort having any type of barrier increased over the long-term intervention period. A majority of the weight loss barriers were significantly associated with younger age, greater obesity, and non-Caucasian race/ethnicity (p-values vary). Physical activity barriers, particularly thought and mood cues, social cues and time management, physical injury or illness and access/weather, were most significantly associated with being female and obese (p 90% long term) and regularly reviewed self-monitoring skills. More costly approaches were used infrequently during the first 16 sessions (≤10%) but increased over 3.2 years. Conclusion: Behavioral problem solving approaches have short and long term dissemination potential for many kinds of participant barriers. Given minimal resources, increased attention to training lifestyle coaches in the consistent use of these approaches appears warranted
Ageing well with diabetes: A workshop to co‐design research recommendations for improving the diabetes care of older people
Aims:To identify key research questions where answers could improve care for older people living with diabetes (PLWD), and provide detailed recommendations for researchers and research funders on how best to address them.Methods:A series of online research workshops were conducted, bringing together a range of PLWD and an acknowledged group of academic and clinical experts in their diabetes care to identify areas for future research. Throughout the pre-workshop phase, during each workshop, and in manuscript preparation and editing, PLWD played an active and dynamic role in discussions as part of both an iterative and narrative process.Results:The following key questions in this field were identified, and research recommendations for each were developed:How can we improve our understanding of the characteristics of older people living with diabetes (PLWD) and their outcomes, and can this deliver better person-centred care?How are services to care for older PLWD currently delivered, both for their diabetes and other conditions? How can we optimise and streamline the process and ensure everyone gets the best care, tailored to their individual needs?What tools might be used to evaluate the level of understanding of diabetes in the older population amongst non-specialist Healthcare Professionals (HCPs)?How can virtual experts or centres most effectively provide access to specialist multi-disciplinary team (MDT) expertise for older PLWD and the HCPs caring for them?Is a combination of exercise and a nutrition-dense, high protein diet effective in the prevention of the adverse effects of type 2 diabetes and deterioration in frailty, and how might this be delivered in a way which is acceptable to people with type 2 diabetes?How might we best use continuous glucose monitoring (CGM) in older people and, for those who require support, how should the data be shared?How can older PLWD be better empowered to manage their diabetes in their own home, particularly when living with additional long-term conditions?What are the benefits of models of peer support for older PLWD, both when living independently and when in care?Conclusions:This paper outlines recommendations supported by PLWD through which new research could improve their diabetes care and calls on the research community and funders to address them in future research programmes and strategies
Direct Analysis of Aerosolized Chemical Warfare Simulants Captured on a Modified Glass-Based Substrate by “Paper-Spray” Ionization
Paper spray ionization mass spectrometry offers a rapid alternative platform requiring no sample preparation. Aerosolized chemical warfare agent (CWA) simulants trimethyl phosphate, dimethyl methylphosphonate, and diisopropyl methylphosphonate were captured by passing air through a glass fiber filter disk within a disposable paper spray cartridge. CWA simulants were aerosolized at varying concentrations using an in-house built aerosol chamber. A custom 3D-printed holder was designed and built to facilitate the aerosol capture onto the paper spray cartridges. The air flow through each of the collection devices was maintained equally to ensure the same volume of air sampled across methods. Each approach yielded linear calibration curves with R2 values between 0.98–0.99 for each compound and similar limits of detection in terms of disbursed aerosol concentration. While the glass fiber filter disk has a higher capture efficiency (≈40%), the paper spray method produces analogous results even with a lower capture efficiency (≈1%). Improvements were made to include glass fiber filters as the substrate within the paper spray cartridge consumable. Glass fiber filters were then treated with ammonium sulfate to decrease chemical interaction with the simulants. This allowed for improved direct aerosol capture efficiency (>40%). Ultimately, the limits of detection were reduced to levels comparable to current worker population limits of 1 × 10–6 mg/m3
Cyanogen in NGC 1851 red giant branch and asymptotic giant branch stars: Quadrimodal distributions
The Galactic globular cluster NGC 1851 has raised much interest since Hubble Space Telescope photometry revealed that it hosts a double subgiant branch. Here we report on our homogeneous study into the cyanogen (CN) band strengths in the red giant branc
Argos - III. Stellar populations in the galactic bulge of the milky way
We present the metallicity results from the ARGOS spectroscopic survey of the Galactic bulge. Our aim is to understand the formation of the Galactic bulge: did it form via mergers, as expected from Λ cold dark matter theory, or from disc instabilities,
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