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41.
Business Action Research in Practice—A Strategic Conversation About Conducting Action Research in Business Organizations 总被引:1,自引:1,他引:0
Sarah Rod Haslett Tim Molineux John Olsen Jane Stephens John Tepe Susanne Walker Beverly 《Systemic Practice and Action Research》2002,15(6):535-546
The objectiveof this paper is to provide practitioner researchers with insights into the initial findings around the challenges of conducting business action research in practice in commercial settings on the basis of experiences of a PhD cohort at Monash University in the first 18 months of candidature. In performing the role of a concluding paper, it sets out a generic framework for action research that the cohort has come to embrace. In doing so, it draws on emergent themes spread across the six diverse topics that are the subject of action research interventions of the cohort members. The paper then identifies and analyses the common patterns that have emerged and offers observations and conclusions for those involved in practitioner research. 相似文献
42.
43.
Sequence of human tissue inhibitor of metalloproteinases and its identity to erythroid-potentiating activity 总被引:20,自引:0,他引:20
A J Docherty A Lyons B J Smith E M Wright P E Stephens T J Harris G Murphy J J Reynolds 《Nature》1985,318(6041):66-69
Collagen fibres form the stable architecture of connective tissues and their breakdown is a key irreversible step in many pathological conditions. The destruction of collagen is usually initiated by proteinases, the best known of which is the metalloproteinase collagenase (EC 3.4.24). Collagenase and related metalloproteinases are regulated at the level of their synthesis and secretion, through the action of specific stimuli such as hormones and cytokines, and also at the level of their extracellular activity through the action of a specific inhibitor, TIMP (tissue inhibitor of metalloproteinases), which irreversibly forms inactive complexes with metalloproteinases. Although the mechanisms governing the production of TIMP are unknown, immunologically identical forms of this glycoprotein have been detected in a wide variety of human body fluids and cell and tissue culture media. We therefore suggested that under physiological conditions this ubiquitous inhibitor predominates over active metalloproteinases and that tissue destruction may arise when any perturbation of this controlling excess arises. However, further progress towards testing this theory has been hindered by a lack of knowledge about the structure of TIMP and insufficient material for studying it in model systems. Here we describe the structure of TIMP predicted from its complementary DNA, its synthesis in Escherichia coli and transfected animal cells, and the finding that it is identical to a protein recently reported to have erythroid-potentiating activity (EPA). 相似文献
44.
Zusammenfassung Die spontanen Potentiale von Telencephalon-Explantatenin vivo werden durch anästhetische Gase nach anfänglichem Potentialanstieg vermindert bzw. gehemmt. Die Potentiale kommen in ihrer ursprünglichen Form nach Entfernung des Betäubungsmittels mit warmer Luft wieder zurück, und die Explantate sind dann wieder durch dasselbe oder andere Betäubungsmittel beeinflussbar.
This research was supported by a grant from the Office of Naval Research, U.S. Navy Contract NONR 1598 (04). 相似文献
This research was supported by a grant from the Office of Naval Research, U.S. Navy Contract NONR 1598 (04). 相似文献
45.
Restoration of photoreceptor ultrastructure and function in retinal degeneration slow mice by gene therapy 总被引:17,自引:0,他引:17
Ali RR Sarra GM Stephens C Alwis MD Bainbridge JW Munro PM Fauser S Reichel MB Kinnon C Hunt DM Bhattacharya SS Thrasher AJ 《Nature genetics》2000,25(3):306-310
The gene Prph2 encodes a photoreceptor-specific membrane glycoprotein, peripherin-2 (also known as peripherin/rds), which is inserted into the rims of photoreceptor outer segment discs in a complex with rom-1 (ref. 2). The complex is necessary for the stabilization of the discs, which are renewed constantly throughout life, and which contain the visual pigments necessary for photon capture. Mutations in Prph2 have been shown to result in a variety of photoreceptor dystrophies, including autosomal dominant retinitis pigmentosa and macular dystrophy. A common feature of these diseases is the loss of photoreceptor function, also seen in the retinal degeneration slow (rds or Prph2 Rd2/Rd2) mouse, which is homozygous for a null mutation in Prph2. It is characterized by a complete failure to develop photoreceptor discs and outer segments, downregulation of rhodopsin and apoptotic loss of photoreceptor cells. The electroretinograms (ERGs) of Prph2Rd2/Rd2 mice have greatly diminished a-wave and b-wave amplitudes, which decline to virtually undetectable concentrations by two months. Subretinal injection of recombinant adeno-associated virus (AAV) encoding a Prph2 transgene results in stable generation of outer segment structures and formation of new stacks of discs containing both perpherin-2 and rhodopsin, which in many cases are morphologically similar to normal outer segments. Moreover, the re-establishment of the structural integrity of the photoreceptor layer also results in electrophysiological correction. These studies demonstrate for the first time that a complex ultrastructural cell defect can be corrected both morphologically and functionally by in vivo gene transfer. 相似文献
46.
Ice-core measurements indicate that atmospheric CO2 concentrations during glacial periods were consistently about 80 parts per million lower than during interglacial periods. Previous explanations for this observation have typically had difficulty accounting for either the estimated glacial O2 concentrations in the deep sea, 13C/12C ratios in Antarctic surface waters, or the depth of calcite saturation; also lacking is an explanation for the strong link between atmospheric CO2 and Antarctic air temperature. There is growing evidence that the amount of deep water upwelling at low latitudes is significantly overestimated in most ocean general circulation models and simpler box models previously used to investigate this problem. Here we use a box model with deep-water upwelling confined to south of 55 degrees S to investigate the glacial-interglacial linkages between Antarctic air temperature and atmospheric CO2 variations. We suggest that low glacial atmospheric CO2 levels might result from reduced deep-water ventilation associated with either year-round Antarctic sea-ice coverage, or wintertime coverage combined with ice-induced stratification during the summer. The model presented here reproduces 67 parts per million of the observed glacial-interglacial CO2 difference, as a result of reduced air-sea gas exchange in the Antarctic region, and is generally consistent with the additional observational constraints. 相似文献
47.
Pathway of phosphatidylinositol(3,4,5)-trisphosphate synthesis in activated neutrophils. 总被引:22,自引:0,他引:22
Neutrophils activated by the formyl peptide f-Met-Leu-Phe transiently accumulate a small subset of highly polar inositol lipids. A similar family of lipids also appear in many other cells in response to a range of growth factors and activated oncogenes, and are presumed to be the direct or indirect products of 3-phosphatidylinositol kinase. The structures of these lipids are shown to be phosphatidylinositol 3-phosphate, phosphatidylinositol-(3,4)bisphosphate and phosphatidylinositol-(3,4,5)trisphosphate, and we present evidence that in intact neutrophils a phosphatidyl-inositol-(4,5)bisphosphate-3-kinase seems to be the focal point through which agonists stimulate the formation of 3-phosphorylated inositol lipids. 相似文献
48.
49.
Genes mirror geography within Europe 总被引:1,自引:0,他引:1
Novembre J Johnson T Bryc K Kutalik Z Boyko AR Auton A Indap A King KS Bergmann S Nelson MR Stephens M Bustamante CD 《Nature》2008,456(7218):98-101
Understanding the genetic structure of human populations is of fundamental interest to medical, forensic and anthropological sciences. Advances in high-throughput genotyping technology have markedly improved our understanding of global patterns of human genetic variation and suggest the potential to use large samples to uncover variation among closely spaced populations. Here we characterize genetic variation in a sample of 3,000 European individuals genotyped at over half a million variable DNA sites in the human genome. Despite low average levels of genetic differentiation among Europeans, we find a close correspondence between genetic and geographic distances; indeed, a geographical map of Europe arises naturally as an efficient two-dimensional summary of genetic variation in Europeans. The results emphasize that when mapping the genetic basis of a disease phenotype, spurious associations can arise if genetic structure is not properly accounted for. In addition, the results are relevant to the prospects of genetic ancestry testing; an individual's DNA can be used to infer their geographic origin with surprising accuracy-often to within a few hundred kilometres. 相似文献
50.
In contemplating better ways to manage, Stafford Beer says the big problem is that you are not determining absolute facts: you are establishing a set of conventions. Hence his view, that a model is neither true nor false: it is more or less useful. And while this paper suggests Beer’s Viable Systems Model (VSM) is overwhelmingly more, rather than less useful, that the VSM and its founding theories are virtually unknown at the level of everyday management begs the question, why? Over time we have learned about the usefulness of the VSM compared to other management theories, when used in the contest of the organisational strategic planning process. Thus through a sequence of diagrams based on Beer’s original drawings, we show how the VSM came to underpin a process for strategic planning in one organisation. The paper has three aims; to attach an everyday ‘common speak’ understanding to some of Beer’s work, to demonstrate how we have learned to appreciate the usefulness of the VSM and its associated diagrams and conventions and to suggest a link between the Action Research change methodology and Beer’s work. 相似文献