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41.
In this article, we focus on the communicative aspects in action research (AR), and how we as action researchers have been
inspired by working with a theatre company in enterprise development. The theatre showed us a different landscape concerning
communication in the enterprise development process. We discuss how communication in AR traditionally is handled, and challenge
AR by introducing how a theatre company creates engagement and involvement in the development process. Action researchers
can enhance their research activity through using communication forms borrowed from theatrical performance in order to inspire
and increase participants’ involvement in change processes.
相似文献
Kari SkarholtEmail: |
42.
Jens Høyrup 《Archive for History of Exact Sciences》2008,62(6):613-654
The “unknown heritage” is the name usually given to a problem type in whose archetype a father leaves to his first son 1 monetary unit and \({\frac{1}{n}}\) (n usually being 7 or 10) of what remains, to the second 2 units and \({\frac{1}{n}}\) of what remains, and so on. In the end, all sons get the same, and nothing remains. The earliest known occurrence is in Fibonacci’s Liber abbaci, which also contains a number of much more sophisticated versions, together with a partial algebraic solution for one of these and rules for all which do not follow from his algebraic calculation. The next time the problem turns up is in Planudes’s late thirteenth century Calculus according to the Indians, Called the Great. After that the simple problem type turns up regularly in Provençal, Italian and Byzantine sources. It seems never to appear in Arabic or Indian writings, although two Arabic texts (one from c. 1190) contain more regular problems where the number of shares is given; they are clearly derived from the type known from European and Byzantine works, not its source. The sophisticated versions turn up again in Barthélemy de Romans’ Compendy de la praticque des nombres (c. 1467) and, apparently inspired from there, in the appendix to Nicolas Chuquet’s Triparty (1484). Apart from a single trace in Cardano’s Practica arithmetice et mensurandi singularis, the sophisticated versions never surface again, but the simple version spreads for a while to German practical arithmetic and, more persistently, to French polite recreational mathematics. Close examination of the texts shows that Barthélemy cannot have drawn his familiarity with the sophisticated rules from Fibonacci. It also suggests that the simple version is originally either a classical, strictly Greek or Hellenistic, or a medieval Byzantine invention; and that the sophisticated versions must have been developed before Fibonacci within an environment (located in Byzantium, Provence, or possibly in Sicily?) of which all direct traces has been lost, but whose mathematical level must have been quite advanced. 相似文献
43.
Zaitseva II Størling J Mandrup-Poulsen T Berggren PO Zaitsev SV 《Cellular and molecular life sciences : CMLS》2008,65(7-8):1248-1255
An insufficient number of insulin-producing β-cells is a major cause of defective control of blood glucose in both type 1
and type 2 diabetes. The aim of this study was to clarify whether the insulinotropic imidazolines can affect the survival
of highly proliferating insulin-secreting cells, here exemplified by the MIN6 cell line. Our data demonstrate that RX871024,
but not efaroxan, triggered MIN6 cell death and potentiated death induced by a combination of the pro-inflammatory cytokines
interleukin-1β, interferon- γ and tumor necrosis factor-α. These effects did not involve changes in nitric oxide production
but correlated with stimulation of c-jun N-terminal kinase (JNK) activity and activation of caspases-1, -3, -8 and -9. Our
results suggest that the imidazoline RX871024 causes death of highly proliferating insulin-secreting cells, putatively via augmentation of JNK activity, a finding that may impact on the possibility of using compounds of similar activity in the
treatment of diabetes.
Received 13 December 2007; received after revision 5 February 2008; accepted 6 February 2008 相似文献
44.
Frøkjaer-Jensen C Davis MW Hopkins CE Newman BJ Thummel JM Olesen SP Grunnet M Jorgensen EM 《Nature genetics》2008,40(11):1375-1383
At present, transgenes in Caenorhabditis elegans are generated by injecting DNA into the germline. The DNA assembles into a semistable extrachromosomal array composed of many copies of injected DNA. These transgenes are typically overexpressed in somatic cells and silenced in the germline. We have developed a method that inserts a single copy of a transgene into a defined site. Mobilization of a Mos1 transposon generates a double-strand break in noncoding DNA. The break is repaired by copying DNA from an extrachromosomal template into the chromosomal site. Homozygous single-copy insertions can be obtained in less than 2 weeks by injecting approximately 20 worms. We have successfully inserted transgenes as long as 9 kb and verified that single copies are inserted at the targeted site. Single-copy transgenes are expressed at endogenous levels and can be expressed in the female and male germlines. 相似文献
45.
46.
Synnøve Liaaen-Jensen 《Cellular and molecular life sciences : CMLS》1970,26(7):697-710
Zusammenfassung Nach einleitender kurzer Würdigung der Höhepunkte derKarrer'schen Carotinoid-Forschung wird zunächst ein knapper Überblick über den gegenwärtigen Stand der Carotinoid-Forschung gegeben. Die jetzige Kenntnis von Biosynthese und Funktion der Carotinoid-Pigmente wird kurz und die organisch-chemischen Aspekte werden etwas ausführlicher erläutert, und zwar Strukturaufklärung einschliesslich neuer Trennmethoden, unentbehrliche spektroskopische Methoden und neue Reaktionen zur Herstellung von Derivaten sowie schliesslich die Totalsynthese.Anschliessend werden einige ausgewählte Beispiele der NachleseKarrer'scher Beiträge behandelt, nämlich Probleme, die vonKarrer aufgegriffen wurden oder auf andere Weise mitKarrer's Arbeit verbunden sind und später im Laboratorium der Autorin weiter verfolgt wurden. Beispiele von Carotinoiden aus photosynthetischen Bakterien, C50-Carotinoiden, glycosidischen Carotinoiden und Nor-carotinoiden mit Ringverengung werden diskutiert.
Based on a lecture delivered at the Paul Karrer Symposium on 18 April 1969 in Zürich. The original paper contained a more detailed review and evaluation of Karrer's direct contribution to carotenoid research. 相似文献
Based on a lecture delivered at the Paul Karrer Symposium on 18 April 1969 in Zürich. The original paper contained a more detailed review and evaluation of Karrer's direct contribution to carotenoid research. 相似文献
47.
G. C. Gibbons S. Strøbaek B. Haslett D. Boulter 《Cellular and molecular life sciences : CMLS》1975,31(9):1040-1041
Summary The N-terminal sequence of the small subunit of Fraction I protein isolated from tobacco was investigated, using an automatic
protein sequencer. The amino acid sequence of the first 21 residues is presented. 相似文献
48.
Chiral recognition in dimerization of adsorbed cysteine observed by scanning tunnelling microscopy 总被引:3,自引:0,他引:3
Stereochemistry plays a central role in controlling molecular recognition and interaction: the chemical and biological properties of molecules depend not only on the nature of their constituent atoms but also on how these atoms are positioned in space. Chiral specificity is consequently fundamental in chemical biology and pharmacology and has accordingly been widely studied. Advances in scanning probe microscopies now make it possible to probe chiral phenomena at surfaces at the molecular level. These methods have been used to determine the chirality of adsorbed molecules, and to provide direct evidence for chiral discrimination in molecular interactions and the spontaneous resolution of adsorbates into extended enantiomerically pure overlayers. Here we report scanning tunnelling microscopy studies of cysteine adsorbed to a (110) gold surface, which show that molecular pairs formed from a racemic mixture of this naturally occurring amino acid are exclusively homochiral, and that their binding to the gold surface is associated with local surface restructuring. Density-functional theory calculations indicate that the chiral specificity of the dimer formation process is driven by the optimization of three bonds on each cysteine molecule. These findings thus provide a clear molecular-level illustration of the well known three-point contact model for chiral recognition in a simple bimolecular system. 相似文献
49.
Heavy-metal homeostasis and detoxification is crucial for cell viability. P-type ATPases of the class IB (PIB) are essential in these processes, actively extruding heavy metals from the cytoplasm of cells. Here we present the structure of a PIB-ATPase, a Legionella pneumophila CopA Cu(+)-ATPase, in a copper-free form, as determined by X-ray crystallography at 3.2 ? resolution. The structure indicates a three-stage copper transport pathway involving several conserved residues. A PIB-specific transmembrane helix kinks at a double-glycine motif displaying an amphipathic helix that lines a putative copper entry point at the intracellular interface. Comparisons to Ca(2+)-ATPase suggest an ATPase-coupled copper release mechanism from the binding sites in the membrane via an extracellular exit site. The structure also provides a framework to analyse missense mutations in the human ATP7A and ATP7B proteins associated with Menkes' and Wilson's diseases. 相似文献
50.
Lorenzen ED Nogués-Bravo D Orlando L Weinstock J Binladen J Marske KA Ugan A Borregaard MK Gilbert MT Nielsen R Ho SY Goebel T Graf KE Byers D Stenderup JT Rasmussen M Campos PF Leonard JA Koepfli KP Froese D Zazula G Stafford TW Aaris-Sørensen K Batra P Haywood AM Singarayer JS Valdes PJ Boeskorov G Burns JA Davydov SP Haile J Jenkins DL Kosintsev P Kuznetsova T Lai X Martin LD McDonald HG Mol D Meldgaard M Munch K Stephan E Sablin M Sommer RS Sipko T Scott E Suchard MA Tikhonov A Willerslev R 《Nature》2011,479(7373):359-364
Despite decades of research, the roles of climate and humans in driving the dramatic extinctions of large-bodied mammals during the Late Quaternary period remain contentious. Here we use ancient DNA, species distribution models and the human fossil record to elucidate how climate and humans shaped the demographic history of woolly rhinoceros, woolly mammoth, wild horse, reindeer, bison and musk ox. We show that climate has been a major driver of population change over the past 50,000 years. However, each species responds differently to the effects of climatic shifts, habitat redistribution and human encroachment. Although climate change alone can explain the extinction of some species, such as Eurasian musk ox and woolly rhinoceros, a combination of climatic and anthropogenic effects appears to be responsible for the extinction of others, including Eurasian steppe bison and wild horse. We find no genetic signature or any distinctive range dynamics distinguishing extinct from surviving species, emphasizing the challenges associated with predicting future responses of extant mammals to climate and human-mediated habitat change. 相似文献