Absolute dimensions of detached eclipsing binaries. III. The metallic-lined system YZ Cassiopeiae

The bright binary system YZ Cassiopeiae is a remarkable laboratory for studying the Am phenomenon. It consists of a metallic-lined A2 star and an F2 dwarf on a circular orbit, which undergo total and annular eclipses. We present an analysis of 15 published light curves and 42 new high-quality echelle spectra, resulting in measurements of the masses, radii, effective temperatures and photospheric chemical abundances of the two stars. The masses and radii are measured to 0.5% precision: M_A = 2.263 +/- 0.012 Msun, M_B = 1.325 +/- 0.007 Msun, R_A = 2.525 +/- 0.011 Rsun and R_B = 1.331 +/- 0.006 Rsun. We determine the abundance of 20 elements for the primary star, of which all except scandium are super-solar by up to 1 dex. The temperature of this star (9520 +/- 120 K) makes it one of the hottest Am stars. We also measure the abundances of 25 elements for its companion (Teff = 6880 +/- 240 K), finding all to be solar or slightly above solar. The photospheric abundances of the secondary star should be representative of the bulk composition of both stars. Theoretical stellar evolutionary models are unable to match these properties: the masses, radii and temperatures imply a half-solar chemical composition (Z = 0.009 +/- 0.003) and an age of 490-550 Myr. YZ Cas therefore presents a challenge to stellar evolutionary theory.Comment: Accepted for publication in MNRAS. 15 pages, 9 tables, 7 figure

Spectrum Analysis of Bright Kepler late B- to early F- Stars

The Kepler satellite mission delivers single band-pass light curves of a huge number of stars observed in the Cygnus-Lyra region opening a new window for asteroseismology. In order to accomplish one of the preconditions for the asteroseismic modelling of the stars, we aim to derive fundamental parameters and individual abundances for a sample of 18 Gamma Dor (GD)/Delta Sct (DSct) and 8 SPB/beta Cep candidate stars in the Kepler satellite field of view. We use the spectral synthesis method to model newly obtained, high-resolution spectra of 26 stars in order to derive their fundamental parameters and individual abundances. The stars are then placed into the log(Teff)-log(g) diagram and the obtained spectroscopic classification is compared to the existing photometric one. For hot stars, the KIC temperatures appear to be systematically underestimated, in agreement with previous findings. We also find that the temperatures derived from our spectra agree reasonably well with those derived from the SED fitting. According to their position in the log(Teff)-log(g) diagram, two stars are expected GD stars, four stars are expected DSct stars, and four stars are possibly DSct stars at the blue edge of the instability strip. Two stars are confirmed SPB variables, and one star falls into the SPB instability region but its parameters might be biased by binarity. Two of the four stars that fall into the DSct instability region show GD-type oscillation in their light curves implying that GD-like oscillations are much more common among the DSct stars than is theoretically expected. Moreover, one of the stars located at the hot border of the DSct instability strip is classified as DSct-GD hybrid pulsator from its light curve analysis. Given that these findings are fully consistent with recent investigations, we conclude that a revision of the GD and DSct instability strips is essential.Comment: 14 pages, 14 figures, 6 tables; accepted for publication in MNRA

Masks and transformations

1989 Spring.Supplemental zip file includes 19 slides of artwork.I use the mask as a vehicle to carry the symbols I feel call attention to the metaphors which best represent my philosophy of life. Inspired by my studies of Ancient American (Mayan and Anasazi) art and archaeology, I use the jaguar, the bird, the snake and man in metaphoric allegory to parallel the four stages of life. All ideas and expressions in my artwork and in my thesis paper are personal and represent my own view of life

Colonization and parasitism of females and eggs of Meloidogyne incognita by fungi

Root-knot nematodes, especially Meloidogyne incognita, are destructive pathogens of commercially grown tomatoes in East Tennessee. The objective of this study was to determine the relationship between females and eggs of M. incognita and nematophagous fungi. Females were either extracted from heavily infested, field-collected tomato roots with no further treatment, rinsed 3x or 20x with sterile water, or surface-sterilized with 1.05% NaOCl. Females were placed on antibiotic-amended water agar for growth of parasitizing fungi. Female viability was determined by observation of stylet thrusting, metacorpus movement, and egg production. Surface colonization of the female cuticle by fungi was examined with the scanning electron microscope (SEM). Eggs were extracted from field-collected egg masses with 1.05% NaOCl and spread on antibiotic-amended water agar for growth and observation of colonizing fungi. Eggs from greenhouse cultures were suspended in agar on slides or in discs and buried in the field to determine the potential for egg parasitism. In 1987, fungi, primarily Paecilomyces lilacinus, grew from most females (81%) removed from roots and placed on agar. Fungi grew from 37% of the females after sterile water rinses, but were recovered from only 2% of the females treated with NaOCl. All fungal isolates identified from NaOCl-treated females were Paecilomyces spp. Lower percentages of colonization occurred in 1988 but the results were proportionally the same among treatments as those found in 1987. SEM work showed that the cuticular ridges of females, and the hyphae associated with the cuticle, were collapsed by sodium hypochlorite treatment. Parasitism of eggs from egg masses was negligible (\u3c1%), but up to 16% of free eggs buried on agar slides and discs were parasitized. The fungi most commonly isolated from agar discs were Epicoccum purpurascens Ehrenb. ex Schlecht, Humicola grisea Traaen, Paecilomyces lilacinus (Thom) Samson, P. marquandii (Massee) Hughes, several isolates tentatively identified as Phytophthora spp., and two unidentified species

Fluorescence of covalently attached pyrene as a general RNA folding probe

Fluorescence techniques are commonly and powerfully applied to monitor biomolecular folding. In a limited fashion, the fluorescence emission intensity of covalently attached pyrene has been used as a reporter of RNA conformational changes. Here, we pursue two goals: we examine the relationship between tether identity and fluorescence response, and we determine the general utility of pyrene fluorescence to monitor RNA folding. The P4–P6 domain of the Tetrahymena group I intron RNA was systematically modified at multiple nucleotide positions with pyrene derivatives that provide a range of tether lengths and compositions between the RNA and chromophore. Certain tethers typically lead to a superior fluorescence signal upon RNA folding, as demonstrated by equilibrium titrations with Mg(2+). In addition, useful fluorescence responses were obtained with pyrene placed at several nucleotide positions dispersed throughout P4–P6. This suggests that monitoring of tertiary folding by fluorescence of covalently attached pyrene will be generally applicable to structured RNA molecules

Site‐Specific Fluorescent Labeling of Large RNAs with Pyrene

Pyrene is a useful chromophore for monitoring the tertiary structure and folding of large RNAs. This unit describes the general preparation of a large RNA (>80 nucleotides in length) that has been site‐specifically modified with pyrene at the 2′‐position of an individual internal nucleotide. A protocol is provided for derivatizing a 2′‐amino‐RNA oligonucleotide with a suitably activated pyrene reagent. This pyrene‐labeled oligonucleotide is then assembled with other RNA(s) either by covalent ligation or by noncovalent hybridization to form a full‐length structured RNA, which may then be studied by equilibrium and stopped‐flow fluorescence spectroscopy.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143792/1/cpnc1111.pd

Ki67 expression levels are a better marker of reduced melanoma growth following MEK inhibitor treatment than phospho-ERK levels

The loss of tumour phospho-extracellular responsive kinase (pERK) positivity is the major treatment biomarker for mitogen-activated protein kinase/extracellular responsive kinase (MEK) inhibitors. Here, we demonstrate that there is a poor correlation between pERK inhibition and the anti-proliferative effects of MEK inhibitors in melanoma cells. We suggest that Ki67 is a better biomarker for future clinical studies

Can self-management programmes change healthcare utilisation in COPD?: A systematic review and framework analysis

Objective The study aims to evaluate the ability of self-management programmes to change the healthcare-seeking behaviours of people with Chronic Obstructive Pulmonary Disease (COPD), and any associations between programme design and outcomes. Methods A systematic search of the literature returned randomised controlled trials of SMPs for COPD. Change in healthcare utilisation was the primary outcome measure. Programme design was analysed using the Theoretical Domains Framework (TDF). Results A total of 26 papers described 19 SMPs. The most common utilisation outcome was hospitalisation (n = 22). Of these, 5 showed a significant decrease. Two theoretical domains were evidenced in all programmes: skills and behavioural regulation. All programmes evidenced at least 5 domains. However, there was no clear association between TDF domains and utilisation. Overall, study quality was moderate to poor. Conclusion This review highlights the need for more alignment in the goals, design, and evaluation of SMPs. Specifically, the TDF could be used to guide programme design and evaluation in future. Practice implications Practices have a reasonable expectation that interventions they adopt will provide patient benefit and value for money. Better design and reporting of SMP trials would address their ability to do so

Health Risk Behaviors in Insured and Uninsured Community Health Center Patients in the Rural US South

Introduction: The impact of health behaviors on the leading causes of death across the USA has been well demonstrated. However, limited focus has been placed on the leading health risk behaviors of rural Federally-Qualified Health Center (FQHC) patients, a particularly underserved group. The current study was undertaken to examine the most common risk-taking behaviors of rural FQHC patients and to examine if risk-taking behaviors vary between insured and uninsured patients. Methods: A convenience sample of 199 patients was recruited at an FQHC in the rural US South. Participants completed a battery of demographic and health risk behavior assessments. Results: The most common risk behaviors were eating fried foods, not eating five servings of vegetables per day, not eating three servings of fruit per day, drinking caloric beverages, not exercising regularly, not wearing a seatbelt, having sex without a condom and smoking. Uninsured patients were more likely to talk on their cell phones while driving (p Conclusions: Rural FQHC patients demonstrated high levels of behavioral and health risk-taking, including dietary-, exercise- and traffic-related risks, in a context where traditional prevention methods have failed to penetrate. Differences exist between insured and uninsured patients, indicating that the reasons behind behavioral risk-taking may be context-specific and need to be explored further to help identify intervention targets that are culturally and situationally appropriate for diverse rural groups