67 research outputs found
Dioxygen binding is controlled by the protein environment in non-heme FeII and 2-oxoglutarate oxygenases: a study on histone demethylase PHF8 and an ethylene-forming enzyme
Invited for the cover of this issue are Christo Z. Christov and co-workers at Michigan Technological University, University of Oxford, and Michigan State University. The image depicts the oxygen diffusion channel in class 7 histone demethylase (PHF8) and ethylene-forming enzyme (EFE) and changes in the enzymes’ conformations upon binding. Read the full text of the article at 10.1002/chem.202300138
Accounting students' IT applicaton skills over a 10-year period
This paper reports on the changing nature of a range of information technology (IT) application skills that students declare on entering an accounting degree over the period from 1996 to 2006. Accounting educators need to be aware of the IT skills students bring with them to university because of the implications this has for learning and teaching within the discipline and the importance of both general and specific IT skills within the practice and craft of accounting. Additionally, IT skills constitute a significant element within the portfolio of employability skills that are increasingly demanded by employers and emphasized within the overall Higher Education (HE) agenda. The analysis of students' reported IT application skills on entry to university, across a range of the most relevant areas of IT use in accounting, suggest that their skills have continued to improve over time. However, there are significant differential patterns of change through the years and within cohorts. The paper addresses the generalizability of these findings and discusses the implications of these factors for accounting educators, including the importance of recognising the differences that are potentially masked by the general increase in skills; the need for further research into the changing nature, and implications, of the gender gap in entrants' IT application skills; and the low levels of entrants' spreadsheet and database skills that are a cause for concern
WFPC2 Observations of Compact Star Cluster Nuclei in Low Luminosity Spiral Galaxies
We have used the Wide Field Planetary Camera 2 aboard the Hubble Space
Telescope to image the compact star cluster nuclei of the nearby, late-type,
low-luminosity spiral galaxies NGC 4395, NGC 4242, and ESO 359-029. We also
analyze archival WFPC2 observations of the compact star cluster nucleus of M33.
A comparative analysis of the structural and photometric properties of these
four nuclei is presented. All of the nuclei are very compact, with luminosity
densities increasing at small radii to the resolution limit of our data. NGC
4395 contains a Seyfert 1 nucleus with a distinct bipolar structure and bright
associated filaments which are likely due to [OIII] emission. The M33 nucleus
has a complex structure, with elongated isophotes and possible signatures of
weak activity, including a jet-like component. The other two nuclei are not
known to be active, but share similar physical size scales and luminosities to
the M33 and NGC 4395 nuclei. The circumnuclear environments of all four of our
program galaxies are extremely diffuse, have only low-to-moderate star
formation, and appear to be devoid of large quantities of dust. The central
gravitational potentials of the galaxies are also quite shallow, making the
origin of these types of `naked' nuclei problematic.Comment: to appear in the July 1999 Astronomical Journal; 38 pages (Latex), 5
tables (postscript), 21 figures (gif); postscript versions of the figures may
be obtained via anonymous ftp at
ftp://ftp.cv.nrao.edu/NRAO-staff/lmatthew/lanl-nucle
New Period-Luminosity and Period-Color Relations of Classical Cepheids: I. Cepheids in the Galaxy
321 Galactic fundamental-mode Cepheids with good B,V,I photometry by
Berdnikov et al. 2000 and with homogenized color excesses E(B-V) based on
Fernie et al. 1995 are used to determine their P-C relation in the range
0.4<log P<1.6. Distances of 25 Cepheids in open clusters (Feast 1999) and of 28
Cepheids with BBW distances (Gieren et al. 1998) are used in a first step to
determine the absorption coefficients R_B=4.17, R_V=3.17, and R_I=1.89. The two
sets define two independent P-L relations which agree very well in slope. They
are therefore combined into a single mean Galactic P-L relation. Galactic
Cepheids are redder in (B-V) than those in LMC and SMC as shown by the over
1000 Cloud Cepheids with good standard B,V,I photometry by Udalski et al 1999.
Also the (B-V), (V-I) two-color diagrams differ between Cepheids in the Galaxy
and the Clouds, attributed both to the effects of metallicity differences, on
the spectral energy distributions of the Cepheids and to a shift in the
effective temperature of the middle of the instability strip for LMC and SMC
relative to the Galaxy by about Delta log Te ~ 0.02 at M_V=-4.0 mag, hotter for
both LMC and SMC. Differences in the P-C relations between the Galaxy and the
Clouds show that there cannot be a universal P-L relation from galaxy-to-galaxy
in any given color. The inferred non-uniqueness of the slope of the P-L
relations in the Galaxy, LMC, and SMC is born out by the observations. The
Cloud Cepheids follow a shallower overall slope of the P-L relations in B,V,I
than the Galactic ones. LMC and SMC Cepheids are brighter in V than in the
Galaxy by up to 0.5 mag at short periods and fainter at long periods.Comment: 29 pages, 19 figures, 7 tables. Accepted for publication in Astronomy
and Astrophysic
Altered Trabecular Bone Structure and Delayed Cartilage Degeneration in the Knees of Collagen VI Null Mice
Mutation or loss of collagen VI has been linked to a variety of musculoskeletal abnormalities, particularly muscular dystrophies, tissue ossification and/or fibrosis, and hip osteoarthritis. However, the role of collagen VI in bone and cartilage structure and function in the knee is unknown. In this study, we examined the role of collagen VI in the morphology and physical properties of bone and cartilage in the knee joint of Col6a1−/− mice by micro-computed tomography (microCT), histology, atomic force microscopy (AFM), and scanning microphotolysis (SCAMP). Col6a1−/− mice showed significant differences in trabecular bone structure, with lower bone volume, connectivity density, trabecular number, and trabecular thickness but higher structure model index and trabecular separation compared to Col6a1+/+ mice. Subchondral bone thickness and mineral content increased significantly with age in Col6a1+/+ mice, but not in Col6a1−/− mice. Col6a1−/− mice had lower cartilage degradation scores, but developed early, severe osteophytes compared to Col6a1+/+mice. In both groups, cartilage roughness increased with age, but neither the frictional coefficient nor compressive modulus of the cartilage changed with age or genotype, as measured by AFM. Cartilage diffusivity, measured via SCAMP, varied minimally with age or genotype. The absence of type VI collagen has profound effects on knee joint structure and morphometry, yet minimal influences on the physical properties of the cartilage. Together with previous studies showing accelerated hip osteoarthritis in Col6a1−/− mice, these findings suggest different roles for collagen VI at different sites in the body, consistent with clinical data
Learning from success: Improving undergraduate education through understanding the capabilities of successful nurse graduates
This paper reports on a study of nursing graduates identified as high performers by their nursing unit managers. The study involved 17 graduates from two teaching hospitals, one in the inner city of Sydney and the other in regional New South Wales. The
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