103 research outputs found
An exploration of the relationship between school setting and the self-esteem of grade-six girls
This study had three purposes: 1) to explore the relationship of school setting and the self-esteem of grade-six girls, with setting deļ¬ned in terms of elementary (K-6), middle (6-8) and combined (K-8); 2) to explore the relationship of school setting and the self-esteem of grade-six girls, with setting deļ¬ned in terms of urban and rural; 3) to contribute Canadian knowledge to the predominantly American research on the relationship between self-esteem of students and school settings and transitions. Two major theories from this literature emerge. The ļ¬rst, a cumulative change theory, suggests that the cumulative effects of developmental changes and the stress of making transitions are responsible for the drop in girlsā self-esteem. The second, a mismatch theory, points to the mismatch of middle school environments and practices with the developmental stages of youth as the cause of lowered self-esteem. Using an informal questionnaire and the standardized School Form of the Coopersmith Self-Esteem Inventory, this study examined the self-esteem of 130 grade-six girls in samples across the three school settings in each of the rural and urban settings. The design used a single time-point assessment at the end of the grade-six year. Results of the statistical analyses did not support the hypotheses. However, a trend in the data did support the hypothesis that grade-six girls in the middle (6-8) school setting may have lower self-esteem than girls in the other two settings. This study suggests that further research including larger samples and multiple sources of data is indicated. A signiļ¬cant relationship was found between girlsā self-esteem and the experience of changing schools, as well as self-esteem and the employment status of girlsā fathers. There was also a signiļ¬cant relationship between school setting and girlsā reports of being in a couple relationship, although not in the direction expected
What Lies Beneath: How Paranoid Cognition Explains the Relations Between Transgender Employees\u27 Perceptions of Discrimination at Work and their Job Attitudes and Wellbeing
With the recent public gender transitions of celebrities like Caitlin Jenner, greater visibility of transgender characters on television (e.g., Transparent), and controversial laws enacted in some U.S. states and cities banning transgender employees from accessing bathrooms that align with their gender identities, issues of gender expression have been thrust into the national spotlight. In order to promote greater awareness and acceptance of transgender people, greater knowledge of their life experiences is needed. Adding to a small, but growing, body of research on the work experiences of transgender individuals, the goal of the present study is to examine the cognitive processes that shape these individuals\u27 experiences in the workplace. Drawing on existing theory and research on paranoia, we examine the role of paranoid cognition, defined by hypervigilance, rumination, and sinister attributional tendencies, in explaining the relations between transgender employees\u27 perceptions of workplace discrimination and their job attitudes and psychological wellbeing. Our findings suggest that perceptions of transgender discrimination in the workplace are positively related to paranoid cognition at work; paranoid cognition is positively related to transgender employees\u27 turnover intentions and emotional exhaustion and negatively related to their job satisfaction; and paranoid cognition at work mediates the relations between perceptions of discrimination and each of these outcomes. We conclude by discussing the implications of our results, as well as avenues for future research on the work experiences of transgender employees
Functional and structural studies of an Enterococcal Serine/Threonine kinase and its contribution to antibiotic resistance mechanisms
The emergence of vancomycin-resistant enterococci (VRE) since the 1980s has turned this Gram-positive bacterium into a serious and growing clinical challenge. Enterococci have acquired resistance to a number of different antibiotics and are intrinsically resistant to cephalosporin b-lactam drugs. As a result, they are now placed in the World Health Organisation list of priority pathogens for which new antibiotics are urgently needed. An important risk factor for the emergence of VRE is treatment with cephalosporins, suggesting a connection between the origins of resistance between these two different types of antibiotics, the mechanistic basis for which was unknown.
In this study I demonstrate that cephalosporin resistance is significantly enhanced in the well characterized E. faecalis OG1RF strain containing the Tn1549 transposon conferring the VanB type vancomycin resistance. Cephalosporin resistance is shown to be enhanced to the presence of the Tn1549 transposon and a single, chromosomally encoded Serine/Threonine (ST) kinase gene called ireK. Complementation experiments and fluorescence microscopy with a range of biophysical techniques to characterise the protein. Deletion of the gene results in cephalosporin sensitivity. Moreover, this phenotype can be chemically simulated by treatment of E. faecalis with inhibitors of cytoplasmic ST kinases such as staurosporine, demonstrating a requirement for ST kinase activity for cephalosporin resistance. This also demonstrates a therapeutic potential for targeting ST kinases in Gram-positive pathogens with small molecule inhibitors to restore cephalosporin sensitivity which may have clear translational significance. IreK was identified as a key protein involved in enhanced cephalosporin resistance and led to examination of its extracellular and intracellular domains to understand its signal transduction mechanisms and its linkage to resistance. The extracellular domain of IreK was essential for cellular location. Further biophysical experiments identified ligands for the extracellular domains include sugar motifs such as the glycan backbone of peptidoglycans and sugar containing antibiotics. This has led to a new functional model for ST kinases in enterococci
Morally Elevating or Deflating? Investigating When and Why Acts of Oppositional Courage for Social Equity Elicit Positive and Negative Gossip from Majority Group Observers
U Sco 2010 outburst: observational evidence of an underlying ONeMg white dwarf
This paper presents U Sco nebular spectra collected in the period March-May
2010 after the binary outburst on Jan 28, 2010. The spectra display strong [Ne
V] and [Ne III] lines that can be used to compute the relative abundance of
[Ne/O]. The value obtained ([Ne/O]=1.69) is higher than the typical [Ne/O]
abundance found in classical novae from CO progenitors and suggests that U Sco
has a ONeMg white-dwarf progenitor. It follows that U Sco will not explode as a
SN Ia but rather collapse to become a neutron star or a millisecond pulsar.Comment: Accepted for publication on A&A Letter; 4 pages 3 figure
The component masses of the cataclysmic variable V347 Puppis
We present time-resolved spectroscopy and photometry of the double-lined eclipsing cataclysmic variable V347 Pup (=LB 1800). There is evidence of irradiation on the inner hemisphere of the secondary star, which we correct for using a model to give a secondary-star radial velocity of KR= 198 Ā± 5 km sā1. The rotational velocity of the secondary star in V347 Pup is found to be v sin i= 131 Ā± 5 km sā1 and the system inclination is i= 840 Ā± 23. From these parameters we obtain masses of M1= 0.63 Ā± 0.04 Mā for the white dwarf primary and M2= 0.52 Ā± 0.06 Mā for the M0.5V secondary star, giving a mass ratio of q= 0.83 Ā± 0.05. On the basis of the component masses, and the spectral type and radius of the secondary star in V347 Pup, we find tentative evidence for an evolved companion. V347 Pup shows many of the characteristics of the SW Sex stars, exhibiting single-peaked emission lines, high-velocity S-wave components and phase-offsets in the radial velocity curve. We find spiral arms in the accretion disc of V347 Pup and measure the disc radius to be close to the maximum allowed in a pressureless disc
A Radial Velocity Study of CTCV J1300-3052
We present time-resolved spectroscopy of the eclipsing, short period
cataclysmic variable CTCV J1300-3052. Using absorption features from the
secondary star, we determine the radial velocity semi-amplitude of the
secondary star to be K2 = 378 \pm 6 km/s, and its projected rotational velocity
to be v sin i = 125 \pm 7 km/s. Using these parameters and Monte Carlo
techniques, we obtain masses of M1 = 0.79 \pm 0.05 MSun for the white dwarf
primary and M2 = 0.198 \pm 0.029 MSun for the M-type secondary star. These
parameters are found to be in excellent agreement with previous mass
determinations found via photometric fitting techniques, supporting the
accuracy and validity of photometric mass determinations in short period CVs.Comment: Accepted for publication in MNRAS (24th January 2012). 10 pages, 9
figures (black and white
The masses of the cataclysmic variables AC Cancri and V363 Aurigae
We present time-resolved spectroscopy and photometry of the double-lined eclipsing cataclysmic variables AC Cnc and V363 Aur (= Lanning 10). There is evidence of irradiation on the inner hemisphere of the secondary star in both systems, which we correct for using a model that reproduces the observations remarkably well. We find the radial velocity of the secondary star in AC Cnc to be KR= 176 Ā± 3 km sā1 and its rotational velocity to be v sin i= 135 Ā± 3 km sā1. From these parameters we obtain masses of M1= 0.76 Ā± 0.03 Mā for the white-dwarf primary and M2= 0.77 Ā± 0.05 Mā for the K2 Ā± 1V secondary star, giving a mass ratio of q= 1.02 Ā± 0.04. We measure the radial and rotational velocities of the G7 Ā± 2V secondary star in V363 Aur to be KR= 168 Ā± 5 km sā1 and v sin i= 143 Ā± 5 km sā1, respectively. The component masses of V363 Aur are M1= 0.90 Ā± 0.06 Mā and M2= 1.06 Ā± 0.11 Mā, giving a mass ratio of q= 1.17 Ā± 0.07. The mass ratios for AC Cnc and V363 Aur fall within the theoretical limits for dynamically and thermally stable mass transfer. Both systems are similar to the SW Sex stars, exhibiting single-peaked emission lines with transient absorption features, high-velocity S-wave components and phase-offsets in their radial-velocity curves. The Balmer lines in V363 Aur show a rapid increase in flux around phase 0 followed by a rapid decrease, which we attribute to the eclipse of an optically thick region at the centre of the disc. This model could also account for the behaviour of other SW Sex stars where the Balmer lines show only a shallow eclipse compared to the continuum
VV Pup in a low state: secondary-star irradiation or stellar activity?
Aims. Emission lines in polars show complex profiles with multiple components
that are typically ascribed to the accretion stream, threading region,
accretion spot, and the irradiated secondary-star. In low-state polars the
fractional contribution by the accretion stream, and the accretion spot is
greatly reduced offering an opportunity to study the effect of the
secondary-star irradiation or stellar activity. We observed VV Pup during an
exceptional low-state to study and constrain the properties of the line-forming
regions and to search for evidence of chromospheric activity and/or
irradiation. Methods. We obtained phase-resolved optical spectra at the ESO
VLT+FORS1 with the aim of analyzing the emission line profile and radial
velocity as a function of the orbital period. We also tailored irradiated
secondary-star models to compare the predicted and the observed emission lines
and to establish the nature of the line-forming regions. Results. Our
observations and data analysis, when combined with models of the irradiated
secondary-star, show that, while the weak low ionization metal lines (FeI and
MgI) may be consistent with irradiation processes, the dominant Balmer H
emission lines, as well as NaI and HeI, cannot be reproduced by the irradiated
secondary-star models. We favor the secondary-star chromospheric activity as
the main forming region and cause of the observed H, NaI, and He emission
lines, though a threading region very close to the L1 point cannot be excluded.Comment: 10 pages, 9 figures, in press on A&
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