Background. Collaborative nursing research across academic and practice settings is imperative to generate knowledge to improve patient care. Models of academic/practice partnerships for nursing ...research are lacking. This paper reports data collected before and during a one-day retreat for nurse researchers and administrators from local universities and health care organizations designed to establish a regional nursing research partnership. Methods. Quantitative and qualitative methods were used to address the study aims: (1) to assess research involvement and institutional research resources; (2) to assess interest in and concerns regarding cross-institutional collaborations; and (3) to describe perceptions of the purpose of a partnership and resources needed to ensure success. Results. Participants had differing perceptions of accessibility to resources; participants in practice settings reported less accessibility to resources, notably grant development, informatics, and research assistant support. Participants were interested in collaboration although concerns about conflict of interest were expressed. Four themes related to partnering were identified: harnessing our nursing voice and identity; developing as researchers; staying connected; and positioning for a collaborative project. Conclusion. Academic-practice research collaborations will become increasingly important with health care system changes. Strategies to develop and sustain productive partnerships should be supported. 14 references
The relationship between an initial mechanical event causing brain tissue deformation and delayed neurodegeneration in vivo is complex because of the multiplicity of factors involved. We have used a ...simplified brain surrogate based on rat hippocampal slices grown on deformable silicone membranes to study stretch-induced traumatic brain injury. Traumatic injury was induced by stretching the culture substrate, and the biological response characterized after 4 days. Morphological abnormalities consistent with traumatic injury in humans were widely observed in injured cultures. Synaptic function was significantly reduced after a severe injury. The N-methyl-D-aspartate (NMDA) receptor antagonist MK-801 attenuated neuronal damage, prevented loss of microtubule-associated protein 2 immunoreactivity and attenuated reduction of synaptic function. In contrast, the NMDA receptor antagonists 3-(R)-2-carboxypiperazin-4-yl-propyl-1-phosphonic acid (CPP) and GYKI53655, were neuroprotective in a moderate but not a severe injury paradigm. Nifedipine, an L-type voltage-dependent calcium channel antagonist was protective only after a moderate injury, whereas ω-conotoxin attenuated damage following severe injury. These results indicate that the mechanism of damage following stretch injury is complex and varies depending on the severity of the insult. In conclusion, the pharmacological, morphological and electrophysiological responses of organotypic hippocampal slice cultures to stretch injury were similar to those observed in vivo. Our model provides an alternative to animal testing for understanding the mechanisms of post-traumatic delayed cell death and could be used as a high-content screen to discover neuroprotective compounds before advancing to in vivo models.
On the genealogy of the Orphan Stream Sales, Laura V.; Helmi, Amina; Starkenburg, Else ...
Monthly notices of the Royal Astronomical Society,
09/2008, Letnik:
389, Številka:
3
Journal Article
The local density of halo giants Morrison, Heather L.
The Astronomical journal,
08/1993, Letnik:
106, Številka:
2
Journal Article
Recenzirano
A new estimate of the local density of halo giants - 36 +/- 7 with M(V) less than 0.5 per cu kpc - is presented. This number is derived from an objective-prism survey for nearby metal-weak stars, and ...so is free from many of the assumptions needed to derive the local halo density in the traditional way, from high proper motion surveys. This number agrees well with estimates of the local density of halo horizontal-branch stars, but is approximately a factor of 2 smaller than the density derived by Bahcall and Casertano (1986). This may be due to the inclusion of some thick disk stars in their proper-motion selected sample. The halo density derived from giants can be expressed as a disk-to-halo ratio of 850:1 (+/- 35 percent). Using these results, a simple model is built to predict numbers of halo giants in specified directions in the Galaxy. It is shown that it performs much better than the Bahcall-Soniera model, in the specific case of halo giants. The surface brightness due to the halo at the solar radius is calculated to be 27.7 V magnitudes per sq arcsec, if the Galaxy was viewed from the outside, edge-on, thus raising the possibility of detecting light from halo field stars in other galaxies similar to our own.
A sample of G and K giants, approximately 4 kpc away from the sun, covering the abundance range from disk to halo in a field chosen to measure rotational kinematics, is discussed. To study the disk ...to halo transition, the sample has been enlarged with similar samples of stars in the solar neighborhood to include almost 200 giants and the concept of 'thick disk' has been introduced. For selected giants, abundances, distances, and reddenings are derived, and velocity dispersion is estimated. From the data presented, it is concluded that the disk and halo abundance distributions overlap and that their kinematics are discontinuous. The kinematics of the metal-weak red giants, with abundances extended as low as Fe/H = -1.6, is compared with the kinematics of the halo objects, and the data are interpreted with respect to the thick disk, the halo kinematics, and the theories of galaxy formation. (B.P.)
We present extremely deep charge coupled device (CCD) surface photometry of the edge-on Sc galaxy NGC 5907. Our data reach reliably to a surface brightness of R=27 mag/sq arcsec, some two magnitudes ...fainter than any previous work. We obtained this improvement using a 2048X2048 CCD with a wide (approximately 24 min) field, which made it possible to sky subtract directly from the galaxy frame, and by taking many dark sky flatfields. Our analysis of these data, using a full 2D model fitting procedure with a detailed error model, confirm the thin disk parameters of van der Kruit & Searle (1981). In particular, we confirm that the galaxy's disk has a radial cutoff and a constant scale height with radius. We find evidence for a stellar warp in this system, which has the same orientation as the H I warp. Our deep data also confirm that NGC 5907 has no thick disk. This suggests that theories of thick disk formation from star formation in the early stages of disk collapse, or by secular heating mechanisms, are unlikely to be correct, because they would predict that every galaxy would have a thick disk. Thick disk formation from the accretion of satellite galaxies is more likely.
Epidemiological studies have established the carcinogenic risk of occupational exposure to aromatic amines such as benzidine, beta-naphthylamine, and 4-aminobiphenyl. Metabolic activation of these ...chemicals to reactive, genotoxic electrophiles, via enzymatic N-oxidation and subsequent conjugation reactions, is necessary for their carcinogenic potential to be realized. Many aromatic amines are mutagenic in prokaryotic test systems, in the presence of exogenous mammalian activating enzymes such as those contained in hepatic 9000 x g supernatant. However, in the Ames (Salmonella typhimurium) assay, induction of mutations by aromatic amines and nitroarenes is also almost completely dependent upon the activity of the endogenous bacterial enzyme, N-acetyltransferase/O-acetyltransferase. The relevance of this assay to the prediction of the carcinogenic potential of aromatic amines in humans is thus restricted by the likelihood that the bacterial and human enzymes possess different substrate specificities. In this paper we report the construction and use of new tester strains of S. typhimurium that express high levels of functional human arylamine N-acetyltransferases, NAT1 and NAT2, retaining characteristic arylamine substrate specificities that are distinct from those of the bacterial enzyme. These new strains support the mutagenic activation of benzidine, 2-aminofluorene and 2-amino-3,4-dimethylimidazo4,5-fquinoline in the Ames test and may provide a new tool for evaluating the carcinogenic potential of aromatic amines.
A sample of approximately 100 predominantly metal-weak giants, identified in a high-latitude field towards the galactic center using an automated objective-prism survey technique, is presented. ...Abundances and radial velocities have been measured for these giants, whose distances from the Sun range from 1 to 18 kpc. While the extremely metal-weak stars in the field have halo kinematics, the majority of the stars with intermediate abundance have thick disk kinematics, despite the fact that their average distance from the galactic plane is 3 kpc. The most satisfactory explanation for this effect is that the inner halo is moderately flattened, and the metal-weak stars of the thick disk have a scale height of about 2 kpc. It is suggested that the thick disk may have formed in a dissipational collapse, rather than in a separate event such as the accretion of a small satellite galaxy.
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