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11.
This article presents a theoretical and empirical analysis of Action Engagement. This is a methodological approach implying that researchers involve themselves in the organization by working as ordinary employees. Our problem statement is this: How will Action Engagement improve the quality of action research? Given the fact that the researcher has limited time to use in the initial phase, we intend to show that Action Engagement is an effective introduction to the daily organizational life. The data is from an automotive supplier and two hospitals in Norway. The analysis contributes to the field of action research in two respects. First, it offers a detailed and varied understanding of how a broad empirical basis can be obtained in an action research (AR) project. Second, it presents an empirically grounded understanding of how this method can be used to achieve increased credibility and trust in ways that enable the researcher to bring in new and important aspects in organizational dialogues.  相似文献   
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Watanabe O  Jouzel J  Johnsen S  Parrenin F  Shoji H  Yoshida N 《Nature》2003,422(6931):509-512
Recent ice core studies have raised the disturbing possibility that glacial-interglacial climate changes may be non-uniform across Antarctica. These findings have been confined to records from the Ross Sea sector of the continent, but significant deviations in other areas would call into question the widely assumed validity of the climate record obtained from Vostok, East Antarctica, on large spatial scales. Here we present an isotopic profile from a core drilled at Dome Fuji, situated 1,500 km from Vostok in a different sector of East Antarctica. The two records show remarkable similarities over the past three glacial cycles (the extent of the Dome Fuji record) in both large-amplitude changes, such as terminations, interglacials and interstadials and more subtle glacial events, even when the origin of precipitation is accounted for. Our results indicate that Antarctic climate is essentially homogeneous at the scale of the East Antarctic Plateau, possibly as a consequence of the symmetry of the plateau and the adjacent ocean.  相似文献   
13.
Two deep ice cores from central Greenland, drilled in the 1990s, have played a key role in climate reconstructions of the Northern Hemisphere, but the oldest sections of the cores were disturbed in chronology owing to ice folding near the bedrock. Here we present an undisturbed climate record from a North Greenland ice core, which extends back to 123,000 years before the present, within the last interglacial period. The oxygen isotopes in the ice imply that climate was stable during the last interglacial period, with temperatures 5 degrees C warmer than today. We find unexpectedly large temperature differences between our new record from northern Greenland and the undisturbed sections of the cores from central Greenland, suggesting that the extent of ice in the Northern Hemisphere modulated the latitudinal temperature gradients in Greenland. This record shows a slow decline in temperatures that marked the initiation of the last glacial period. Our record reveals a hitherto unrecognized warm period initiated by an abrupt climate warming about 115,000 years ago, before glacial conditions were fully developed. This event does not appear to have an immediate Antarctic counterpart, suggesting that the climate see-saw between the hemispheres (which dominated the last glacial period) was not operating at this time.  相似文献   
14.
本文介绍了逐差法处理物理实验数据的基本方法和适用范围,表明了逐差法处理实验数据的优点.  相似文献   
15.
Foerster K  Delhey K  Johnsen A  Lifjeld JT  Kempenaers B 《Nature》2003,425(6959):714-717
Females in a variety of species commonly mate with multiple males, and there is evidence that they benefit by producing offspring of higher genetic quality; however, the nature of these genetic benefits is debated. Enhanced offspring survival or quality can result from intrinsic effects of paternal genes---'good genes'--or from interactions between the maternal and paternal genomes--'compatible genes'. Evidence for the latter process is accumulating: matings between relatives lead to decreased reproductive success, and the individual level of inbreeding--measured as average heterozygosity--is a strong fitness predictor. Females should thus benefit from mating with genetically dissimilar males. In many birds, social monogamy restricts mate choice, but females may circumvent this by pursuing extra-pair copulations. Here we show that female blue tits, Parus caeruleus, increase the heterozygosity of their progeny through extra-pair matings. Females thereby produce offspring of higher reproductive value, because less inbred individuals have increased survival chances, a more elaborate male secondary sexual trait (crown colour) and higher reproductive success. The cost of inbreeding may therefore be an important factor driving the evolution of female extra-pair mating.  相似文献   
16.
Radioresistance in cells with high content of metallothionein   总被引:6,自引:0,他引:6  
Summary An endogenous cytoplasmic protein, metallothionein (MT) apparently gave rise to radioresistance in 2 different cell lines. A dose reduction factor of 1.9 was achieved in MT-containing cells. MT accounted for a 3–4-fold increase of total sulfhydryl groups in the resistant cell strains, compared to the non-resistant lines from which they were derived. The protein is rich in cysteine (30%), an amino acid known to give radioprotection when administered exogeneously. Glutathione levels and cell-cycle phase distribution showed no marked difference between resistant and corresponding non-resistant cells.We thank Dr F. Devik, Dr L. Eldjarn and Dr E. Jellum for stimulating discussions, and Miss A. K. Syversen and Mrs T. Nysted for skillful technical assistance. This work was partly supported by the Norgwegian Council for Science and the Humanitites. LE is a fellow of the Norwegian Society for Fighting Cancer.  相似文献   
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