395 research outputs found
Context and violence in individual prayers for protection
The individual prayers for protection within the Psalter are marked by a consistency in terms of the context supposed and the nature of violence experienced by the psalmists. Consistently, these psalms also assert that the right to retributive violence against the enemies belongs to Yahweh alone. Such a consistent pattern indicates that those responsible for assembling the Book of Psalms intended to model this as the appropriate response for the faithful.Continued 2001 as 'Verbum et Ecclesia'Spine cut of Journal binding and pages scanned on flatbed EPSON Expression 10000 XL; 400dpi; text/lineart - black and white - stored to Tiff Derivation: Abbyy Fine Reader v.9 work with PNG-format (black and white); Photoshop CS3; Adobe Acrobat v.9 Web display format PDFhttp://explore.up.ac.za/record=b102527
The chemical composition of Ultracompact Dwarf Galaxies in the Virgo and Fornax Clusters
We present spectroscopic observations of ultra compact dwarf (UCD) galaxies
in the Fornax and Virgo Clusters made to measure and compare their stellar
populations. The spectra were obtained on the Gemini-North (Virgo) and
Gemini-South (Fornax) Telescopes using the respective Gemini Multi-Object
Spectrographs.
We estimated the ages, metallicities and abundances of the objects from mea-
surements of Lick line-strength indices in the spectra; we also estimated the
ages and metallicities independently using a direct spectral fitting technique.
Both methods re- vealed that the UCDs are old (mean age 10.8 \pm 0.7 Gyr) and
(generally) metal-rich (mean [Fe/H] = -0.8 \pm 0.1). The alpha-element
abundances of the objects measured from the Lick indices are super-Solar.
We used these measurements to test the hypothesis that UCDs are formed by the
tidal disruption of present-day nucleated dwarf elliptical galaxies. The data
are not consistent with this hypothesis because both the ages and abundances
are significantly higher than those of observed dwarf galaxy nuclei (this does
not exclude disruption of an earlier generation of dwarf galaxies). They are
more consistent with the properties of globular star clusters, although at
higher mean metallicity. The UCDs display a very wide range of metallicity
(-1.7 <[Fe/H]< 0.0), spanning the full range of both globular clusters and
dwarf galaxy nuclei.
We confirm previous reports that most UCDs have high metalliticities for
their luminosities, lying significantly above the canonical
metallicitiy-luminosity relation followed by early-type galaxies. In contrast
to previous work we find that there is no significant difference in either the
mean ages or the mean metallicities of the Virgo and Fornax UCD populations.Comment: 15 pages (including references and appendix), 8 figures (including
appendix
Investigating molecular mechanisms of 2A-stimulated ribosomal pausing and frameshifting in Theilovirus.
Funder: Helmholtz AssociationFunder: Royal SocietyThe 2A protein of Theiler's murine encephalomyelitis virus (TMEV) acts as a switch to stimulate programmed -1 ribosomal frameshifting (PRF) during infection. Here, we present the X-ray crystal structure of TMEV 2A and define how it recognises the stimulatory RNA element. We demonstrate a critical role for bases upstream of the originally predicted stem-loop, providing evidence for a pseudoknot-like conformation and suggesting that the recognition of this pseudoknot by beta-shell proteins is a conserved feature in cardioviruses. Through examination of PRF in TMEV-infected cells by ribosome profiling, we identify a series of ribosomal pauses around the site of PRF induced by the 2A-pseudoknot complex. Careful normalisation of ribosomal profiling data with a 2A knockout virus facilitated the identification, through disome analysis, of ribosome stacking at the TMEV frameshifting signal. These experiments provide unparalleled detail of the molecular mechanisms underpinning Theilovirus protein-stimulated frameshifting
On the Gaseous Exchange of Ammonia between Leaves and the Environment: Determination of the Ammonia Compensation Point
Uniting Old Stellar Systems: From Globular Clusters to Giant Ellipticals
Here we examine the relationship between the virial and stellar mass for a
range of old stellar systems, from GCs to giant ellipticals, and including such
Intermediate Mass Objects (IMOs). Improvements on previous work in this area
include the use of (i) near-infrared magnitudes from the 2MASS survey, (ii)
aperture corrections to velocity dispersions, (iii) homogeneous half light
radii and (iv) accounting for the effects of non-homology in galaxies. We find
a virial-to-stellar mass relation that ranges from ~10 M_o systems (GCs) to
~10 M_o systems (elliptical galaxies). The lack of measured velocity
dispersions for dwarf ellipticals with -16 > M_K > -18 (~10 M_o) currently
inhibits our ability to determine how, or indeed if, these galaxies connect
continuously with GCs in terms of their virial-to-stellar mass ratios. We find
elliptical galaxies to have roughly equal fractions of dark and stellar matter
within a virial radius; only in the most massive (greater than 10 M_o)
ellipticals does dark matter dominate the virial mass. Although the IMOs reveal
slightly higher virial-to-stellar mass ratios than lower mass GCs, this may
simply reflect our limited understanding of their IMF (and hence their stellar
mass-to-light ratios) or structural properties. We argue that most of these
intermediate mass objects are a natural extension of the GC sequence to higher
masses, i.e. IMOs are essentially massive star clusters. [Abridged].Comment: 15 pages, 14 figures, 1 table, submitted to MNRAS 22/5/08, Revised to
include data from Mieske etal. (0806.0374), accepted by MNRAS 22/7/08. See
http://astronomy.swin.edu.au/dforbes for full Tabl
Spatially Resolved Kinematics of an Ultra-Compact Dwarf Galaxy
We present the internal kinematics of UCD3, the brightest known ultra-compact
dwarf galaxy (UCD) in the Fornax cluster, making this the first UCD with
spatially resolved spectroscopy. Our study is based on seeing-limited
observations obtained with the ARGUS Integral Field Unit of the VLT/FLAMES
spectrograph under excellent seeing conditions (0.5 - 0.67 arcsec FWHM). The
velocity field of UCD3 shows the signature of weak rotation, comparable to that
found in massive globular clusters. Its velocity dispersion profile is fully
consistent with an isotropic velocity distribution and the assumption that mass
follows the light distribution obtained from Hubble Space Telescope imaging. In
particular, there is no evidence for the presence of an extended dark matter
halo contributing a significant (>~33 per cent within R < 200 pc) mass
fraction, nor for a central black hole more massive than ~5 per cent of the
UCD's mass. While this result does not exclude a galaxian origin for UCD3, we
conclude that its internal kinematics are fully consistent with it being a
massive star cluster.Comment: 5 pages, 3 figures; accepted for publication in MNRAS Letter
Burnout and psychiatric morbidity among medical students entering clinical training: a three year prospective questionnaire and interview-based study
BACKGROUND: Mental distress among medical students is often reported. Burnout has not been studied frequently and studies using interviewer-rated diagnoses as outcomes are rarely employed. The objective of this prospective study of medical students was to examine clinically significant psychiatric morbidity and burnout at 3(rd )year of medical school, considering personality and study conditions measured at 1(st )year. METHODS: Questionnaires were sent to 127 first year medical students who were then followed-up at 3(rd )year of medical school. Eighty-one of 3(rd )year respondents participated in a diagnostic interview. Personality (HP5-i) and Performance-based self-esteem (PBSE-scale) were assessed at first year, Study conditions (HESI), Burnout (OLBI), Depression (MDI) at 1(st )and 3(rd )years. Diagnostic interviews (MINI) were used at 3(rd )year to assess psychiatric morbidity. High and low burnout at 3(rd )year was defined by cluster analysis. Logistic regressions were used to identify predictors of high burnout and psychiatric morbidity, controlling for gender. RESULTS: 98 (77%) responded on both occasions, 80 (63%) of these were interviewed. High burnout was predicted by Impulsivity trait, Depressive symptoms at 1(st )year and Financial concerns at 1(st )year. When controlling for 3(rd )year study conditions, Impulsivity and concurrent Workload remained. Of the interviewed sample 21 (27%) had a psychiatric diagnosis, 6 of whom had sought help. Unadjusted analyses showed that psychiatric morbidity was predicted by high Performance-based self-esteem, Disengagement and Depression at 1(st )year, only the later remained significant in the adjusted analysis. CONCLUSION: Psychiatric morbidity is common in medical students but few seek help. Burnout has individual as well as environmental explanations and to avoid it, organisational as well as individual interventions may be needed. Early signs of depressive symptoms in medical students may be important to address. Students should be encouraged to seek help and adequate facilities should be available
A survey of people with foot problems related to rheumatoid arthritis and their educational needs
Background
Up to 50% of people with rheumatoid arthritis (RA) have foot symptoms at diagnosis, hence early foot health intervention is recommended and this should include patient education. This study identifies, for the first time, the foot health education (FHE) needs of people with RA.
Methods
An online survey of people with RA (n = 543) captured quantitative data in relation to the aims, methods of delivery, content, timing and accessibility of FHE.
Results
The majority concurred about the aims of FHE. Verbal delivery and websites were the most common methods. Written and verbal FHE were perceived to be the most effective methods. The point of diagnosis was the preferred time to receive it. Lack of access to FHE included minimal focus on foot health during consultations by both health practitioners and patients with RA. Participant gender, age, disease duration and living situation had a statistically significant influence on the results.
Conclusion
Foot health education is rarely considered within the medical consultation. There is a lack of patient and/or health professional awareness of this need with a detrimental impact on foot health. Patients require health professionals to identify their foot education health needs. Tailored foot health education should begin at initial diagnosis
Dynamics of localized structures in vector waves
Dynamical properties of topological defects in a twodimensional complex
vector field are considered. These objects naturally arise in the study of
polarized transverse light waves. Dynamics is modeled by a Vector Complex
Ginzburg-Landau Equation with parameter values appropriate for linearly
polarized laser emission. Creation and annihilation processes, and
selforganization of defects in lattice structures, are described. We find
"glassy" configurations dominated by vectorial defects and a melting process
associated to topological-charge unbinding.Comment: 4 pages, 5 figures included in the text. To appear in Phys. Rev.
Lett. (2000). Related material at http://www.imedea.uib.es/Nonlinear and
http://www.imedea.uib.es/Photonics . In this new version, Fig. 3 has been
replaced by a better on
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