8,113 research outputs found
Exploring the relationship between oil and gas organizational culture and the management of tacit knowledge.
Ten years after the Deepwater Horizon disaster, knowledge management practices directed toward utilizing employee tacit knowledge remain underdeveloped within oil and gas operations. This is despite the management of tacit knowledge being an environmental safeguard, providing collaborative information on learning experiences to reduce environmental/financial risk, and promoting environmentally sustainable practices. Managing tacit knowledge is a research theme with limited exploration within an oil and gas context. This research addresses this gap and analyzes two oil and gas companies of differing size and scale. A qualitative investigation with key stakeholders is undertaken based on Hansen et al.'s "Codification vs. Personalization" framework. The findings of this research support that the organizational culture within the two oil and gas companies influences their attitudes and behaviors towards their management of tacit knowledge. It identifies an organizational culture that is short-term in focus, reactionary, risk-averse and possessing a fear of change. Factors for limiting effective management of tacit knowledge include organizational structure (especially the use of temporary contractors), hiring policies, and approaches to codification and personalization. These current practices leave a picture of an industry that uses knowledge management strategies for individual and organizational "competitive advantage" rather than for wider beneficial sharing and collaborative learning
Far Ultraviolet Spectroscopic Explorer Survey of Magellanic Cloud Supernova Remnants
We report the progress to date from an ongoing unbiased ultraviolet survey of
supernova remnants in the Magellanic Clouds using the Far Ultraviolet
Spectroscopic Explorer (FUSE) satellite. This survey is obtaining spectra of a
random large sample of Magellanic Cloud supernova remnants with a broad range
of radio, optical, and X-ray properties. To date, 39 objects have been observed
in the survey (38 in the LMC and one in the SMC) and 15 have been detected, a
detection rate of nearly 40%. Our survey has nearly tripled the number of
UV-detected SNRs in the Magellanic Clouds (from 8 to 22). Because of the
diffuse source sensitivity of FUSE, upper limits on non-detected objects are
quite sensitive in many cases. Estimated total luminosities in O~VI span a
broad range from considerably brighter to many times fainter than the inferred
soft X-ray luminosities, indicating that O~VI can be an important and largely
unrecognized coolant in certain objects. We compare the optical and X-ray
properties of the detected and non-detected objects but do not find a simple
indicator for ultraviolet detectability. Non-detections may be due to
clumpiness of the emission, high foreground extinction, slow shocks whose
emission gets attenuated by the Magellanic interstellar medium, or a
combination of these effects.Comment: 34 pages, 26 figures in 8 separate JPG figure files; the
characteristics of individual detected supernova remnants are summarized in
an Appendi
Do Mirrors for Gravitational Waves Exist?
Thin superconducting films are predicted to be highly reflective mirrors for
gravitational waves at microwave frequencies. The quantum mechanical
non-localizability of the negatively charged Cooper pairs, which is protected
from the localizing effect of decoherence by an energy gap, causes the pairs to
undergo non-picturable, non-geodesic motion in the presence of a gravitational
wave. This non-geodesic motion, which is accelerated motion through space,
leads to the existence of mass and charge supercurrents inside the
superconducting film. On the other hand, the decoherence-induced localizability
of the positively charged ions in the lattice causes them to undergo
picturable, geodesic motion as they are carried along with space in the
presence of the same gravitational wave. The resulting separation of charges
leads to a virtual plasma excitation within the film that enormously enhances
its interaction with the wave, relative to that of a neutral superfluid or any
normal matter. The existence of strong mass supercurrents within a
superconducting film in the presence of a gravitational wave, dubbed the
"Heisenberg-Coulomb effect," implies the specular reflection of a gravitational
microwave from a film whose thickness is much less than the London penetration
depth of the material, in close analogy with the electromagnetic case. The
argument is developed by allowing classical gravitational fields, which obey
Maxwell-like equations, to interact with quantum matter, which is described
using the BCS and Ginzburg-Landau theories of superconductivity, as well as a
collisionless plasma model. Several possible experimental tests of these ideas,
including mesoscopic ones, are presented alongside comments on the broader
theoretical implications of the central hypothesis.Comment: 59 pages, 2 figure
Effects of DNA and protein size on substrate cleavage by human tyrosyl-DNA phosphodiesterase 1
Tyrosyl-DNA phosphodiesterase 1 (TDP1) catalyzes the hydrolysis of phosphodiester linkages between a DNA 3′ phosphate and a tyrosine residue as well as a variety of other DNA 3′ substituents, and has been implicated in the repair of covalent complexes involving eukaryotic type IB topoisomerases. To better understand the substrate features that are recognized by TDP1, the size of either the DNA or protein component of the substrate was varied. Competition experiments and gel shift analyses comparing a series of substrates with DNA lengths increasing from 6 to 28 nucleotides indicated that, contrary to predictions based on the crystal structure of the protein, the apparent affinity for the substrate increased as the DNA length was increased over the entire range tested. It has previously been found that a substrate containing the full-length native form of human topoisomerase I protein is not cleaved by TDP1. Protein-oligonucleotide complexes containing either a 53 or 108 amino acid long topoisomerase I-derived peptide were efficiently cleaved by TDP1, but like the full length protein, a substrate containing a 333 amino acid topoisomerase I fragment was resistant to cleavage. Consistent with these results, evidence is presented that processing by the proteasome is required for TDP1 cleavage in vivo
Bayesian modelling of the cool core galaxy group NGC 4325
We present an X-ray analysis of the radio-quiet cool-core galaxy group NGC
4325 (z=0.026) based on Chandra and ROSAT observations. The Chandra data were
analysed using XSPEC deprojection, 2D spectral mapping and forward-fitting with
parametric models. Additionally, a Markov chain Monte Carlo method was used to
perform a joint Bayesian analysis of the Chandra and ROSAT data. The results of
the various analysis methods are compared, particularly those obtained by
forward-fitting and deprojection. The spectral mapping reveals the presence of
cool gas displaced up to 10 kpc from the group centre. The Chandra X-ray
surface brightness shows the group core to be highly disturbed, and indicates
the presence of two small X-ray cavities within 15 kpc of the group core. The
XSPEC deprojection analysis shows that the group has a particularly steep
entropy profile, suggesting that an AGN outburst may be about to occur. With
the evidence of prior AGN activity, but with no radio emission currently
observed, we suggest that the group in in a pre-outburst state, with the
cavities and displaced gas providing evidence of a previous, weak AGN outburst.Comment: 12 pages, 10 figures; accepted for publication in MNRA
Palliative care services for people with dementia: A synthesis of the literature reporting the views and experiences of professionals and family carers.
The experience of being a carer of a person with dementia at the end of life is expressed in these 12 accounts. This is a synthesis of the concerns and challenges for carers at the end of life. These accounts are often insightful and provide several views of carers' and professionals' experience. Having a close relationship as a carer gives a unique and poignant view. What emerges from this review is a range of perspectives that provide contrasting views of the heterogeneity of carers and professionals. This may be helpful for professionals and policy makers to consider when planning end-of-life care strategies for people with dementia and insights drawn from hearing directly from carers may be powerful learning tools
Racial differences in renal allograft survival: The role of systemic hypertension
Racial differences in renal allograft survival: The role of systemic hypertension. The rate of decline in the number of functioning renal allografts beyond the first year after transplantation has changed little in the last 25 years, and during long-term follow-up most allografts are lost due to chronic transplant rejection or patient death. The recipient race correlates with allograft survival, and African American recipients have a lower allograft survival than Caucasians. The goal of the present study was to identify clinical variables present during the first six months after transplantation that predict the loss of renal allografts beyond six months after transplantation, and in particular to determine the role of systemic hypertension on renal allograft survival in black and white recipients. This study includes 547 recipients of first cadaveric renal allografts performed at The Ohio State University. All patients were treated with a uniform immunosuppressive protocol and had a follow-up of at least three years. By multivariate analysis the following variables correlate with poor allograft survival: an elevated serum creatinine concentration measured six months after transplantation (SCr6mo) (P < 0.0001); black race (P < 0.0001); increasing numbers of acute rejection episodes (ATR) (P = 0.002); and young recipients (P = 0.026). Allograft survival is significantly worse in black (mean allograft half-life of 7.7 ± 1.3 years) than in white recipients (24 ± 3 years) (P < 0.0001). Black recipients also have a significantly higher six month average mean arterial blood pressure (MAP) (105 ± 8 mm Hg) than white recipients (102 ± 7 mm Hg) (P = 0.002). However, the prevalence of hypertension is not significantly different in black (33%) than in white recipients (26%). Furthermore, increasing MAP levels correlate with a shorter allograft half-life in black recipients (P = 0.0002), but not in white recipients (P = 0.84). Allograft survival was eight times shorter in hypertensive black (3.1 ± 0.7 years) than in hypertensive white recipients (24.6 ± 7 years). In contrast, allograft survival was not statistically different between normotensive black and white patients. In conclusion, the presence of poorly controlled systemic hypertension, early after renal transplantation, correlates with poor allograft survival in black recipients. Thus, systemic hypertension may explain, in part, differences in renal allograft survival between black and white patients
Predicting Geographic Variation in Cutaneous Leishmaniasis, Colombia
Predicting Geographic Variation in ACL, Colombi
Multiwavelength observations of the M15 intermediate velocity cloud
We present Westerbork Synthesis Radio Telescope HI images, Lovell Telescope
multibeam HI wide-field mapping, Wisconsin H-alpha Mapper facility images,
William Herschel Telescope longslit echelle CaII observations, and IRAS ISSA 60
and 100 micron coadded images towards the intermediate velocity cloud located
in the general direction of the M15 globular cluster. When combined with
previously-published Arecibo data, the HI gas in the IVC is found to be clumpy,
with peak HI column density of 1.5x10^(20) cm^(-2), inferred volume density
(assuming spherical symmetry) of 24 cm^(-3)/(D kpc), and maximum brightness
temperature at a resolution of 81x14 arcsec of 14 K. The HI gas in the cloud is
warm, with a minimum FWHM value of 5 km/s, corresponding to a kinetic
temperature, in the absence of turbulence, of 540 K. There are indications in
the HI data of 2-component velocity structure in the IVC, indicative of
cloudlets. This velocity structure is also tentatively seen in the CaK spectra,
although the SNR is low. The main IVC condensation is detected by WHAM in
H-alpha with intensities uncorrected for Galactic absorption of upto 1.3
Rayleigh, indicating that the cloud is partially ionised. The FWHM of the
ionised component, at a resolution of 1 degree, exceeds 30 km/s. The spatial
and velocity coincidence of the H-alpha and HI peaks in emission is
qualitatively good. Finally, the 100 and 60 micron IRAS images show spatial
coincidence over a 0.7 degree field, with low and intermediate-velocity gas,
respectively, indicating that the IVC may contain dust.Comment: MNRAS, in pres
Resonant enhancement of the zero-phonon emission from a color center in a diamond cavity
We demonstrate coupling of the zero-phonon line of individual
nitrogen-vacancy centers and the modes of microring resonators fabricated in
single-crystal diamond. A zero-phonon line enhancement exceeding ten-fold is
estimated from lifetime measurements at cryogenic temperatures. The devices are
fabricated using standard semiconductor techniques and off-the-shelf materials,
thus enabling integrated diamond photonics.Comment: 5 pages, 4 figure
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