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41.
Scientific Methodology (SM) has long suited those who favour analytical and quantitative research in management. Thus the
dilemma between the rigour and relevance of contemporary management research methods is fuelled by action researchers who
keep wanting to contrast Action Research (AR) with SM. This paper presents a Western philosophical view on the development
of belief systems and theory-based methods over time. It thus links the progressive and cumulative development of SM with
the contemporary AR methodology. In doing this it presents a different point of view—that the traditions of SM and AR have
much closer relationships than people often give them credit for. 相似文献
42.
43.
McDermott-Roe C Ye J Ahmed R Sun XM Serafín A Ware J Bottolo L Muckett P Cañas X Zhang J Rowe GC Buchan R Lu H Braithwaite A Mancini M Hauton D Martí R García-Arumí E Hubner N Jacob H Serikawa T Zidek V Papousek F Kolar F Cardona M Ruiz-Meana M García-Dorado D Comella JX Felkin LE Barton PJ Arany Z Pravenec M Petretto E Sanchis D Cook SA 《Nature》2011,478(7367):114-118
Left ventricular mass (LVM) is a highly heritable trait and an independent risk factor for all-cause mortality. So far, genome-wide association studies have not identified the genetic factors that underlie LVM variation, and the regulatory mechanisms for blood-pressure-independent cardiac hypertrophy remain poorly understood. Unbiased systems genetics approaches in the rat now provide a powerful complementary tool to genome-wide association studies, and we applied integrative genomics to dissect a highly replicated, blood-pressure-independent LVM locus on rat chromosome 3p. Here we identified endonuclease G (Endog), which previously was implicated in apoptosis but not hypertrophy, as the gene at the locus, and we found a loss-of-function mutation in Endog that is associated with increased LVM and impaired cardiac function. Inhibition of Endog in cultured cardiomyocytes resulted in an increase in cell size and hypertrophic biomarkers in the absence of pro-hypertrophic stimulation. Genome-wide network analysis unexpectedly implicated ENDOG in fundamental mitochondrial processes that are unrelated to apoptosis. We showed direct regulation of ENDOG by ERR-α and PGC1α (which are master regulators of mitochondrial and cardiac function), interaction of ENDOG with the mitochondrial genome and ENDOG-mediated regulation of mitochondrial mass. At baseline, the Endog-deleted mouse heart had depleted mitochondria, mitochondrial dysfunction and elevated levels of reactive oxygen species, which were associated with enlarged and steatotic cardiomyocytes. Our study has further established the link between mitochondrial dysfunction, reactive oxygen species and heart disease and has uncovered a role for Endog in maladaptive cardiac hypertrophy. 相似文献
44.
Rao ZhiGuo Zhu ZhaoYu Jia GuoDong Chen FaHu Barton Loukas Zhang JiaWu Qiang MingRui 《科学通报(英文版)》2010,55(18):1931-1936
Using −24‰ and −14‰ as the endpoints of stable carbon isotopic composition of total organic carbon (δ13CTOC) of surface soil under pure C3 and C4 vegetation, and surface soil δ13CTOC data from eastern China, Australia and the Great Plains of North Amer- ica, we estimate the relative abundance of C3/C4 plants (i.e., the ratio of C3 or C4 biomass to local primary production) in modern vegetation for each region. The relative abundance of modern C3/C4 vegetation from each region is compared to the corresponding climatic parameters (mean annual temperature and precipitation) to explore the relationship between relative C4 abundance and climate. The results indicate that temperature controls the growth of C4 plants. However, even where temperature is high enough for the growth of C4 plants, they will only dominate the landscape when precipitation declines as temperatures increase. Our results are consistent with those of other investigations of the geographic distribution of modern C4 plant species. Therefore, our results provide an important reference for interpretation of past C3/C4 relative abundance records in these three regions. 相似文献
45.
46.
M. Schachter Susanne Barton E. Karpinski 《Cellular and molecular life sciences : CMLS》1973,29(8):973-974
Zusammenfassung Nachweis, dass bei Reizung des N. chorda lingualis der Katze ein Blutdruckeffekt ausbleibt, wenn ein Bradykinin potenzierender Faktor (Präparat BPF) zuvor gegeben wurde.
Acknowledgments. We are greatly indepted to Dr.J. Stewart of the University of Colorado and to Dr.L. Greene of Brookhaven National Laboratories, New York, for kind gifts of synthetic bradykinin potentiators.
This work was supported by grants from the Medical Research Council of Canada and the Alberta Heart Foundation. 相似文献
Acknowledgments. We are greatly indepted to Dr.J. Stewart of the University of Colorado and to Dr.L. Greene of Brookhaven National Laboratories, New York, for kind gifts of synthetic bradykinin potentiators.
This work was supported by grants from the Medical Research Council of Canada and the Alberta Heart Foundation. 相似文献
47.
Robert A Barton 《Nature》2002,415(6868):134-135
Three reports on mammalian brain evolution analyse the same comparative data on brain component volumes but come to partially conflicting conclusions. Clark et al. conclude from their analysis of volumetric brain proportions ("cerebro-types") that cerebellum size is invariant across mammalian taxonomic groups, the neocortex and cerebellum do not co-vary in size (in contradiction to ref. 1), and cerebrotype-based measures identify directional changes in brain architecture. Here I provide evidence that calls each of these conclusions into question. The failure of the cerebrotype measure to identify species differences in brain architecture that are independent of gross brain size undermines the proposal by Clark et al. that it could be useful for detecting evolutionary patterns and phylogenetic relationships. 相似文献
48.
Role of paternal and maternal genomes in mouse development 总被引:14,自引:0,他引:14
There has been much speculation on whether mammalian eggs with two male pronuclei can develop normally. Eggs with two female pronuclei can sometimes develop as far as the 25-somite stage but with only very meagre extraembryonic tissues. We suggested that the genome undergoes specific imprinting during gametogenesis and that some paternal genes may be necessary for normal development of the extraembryonic tissues, in which only the maternal X chromosome remains active. However, the need for the maternal genome for development to term is not yet unequivocally established. The detailed study described here demonstrates that while between 40 and 50% of heterozygous reconstituted eggs with a male and a female pronucleus develop to term, none of the eggs with two male pronuclei does so. Furthermore, embryos in the latter case are very retarded, even though the trophoblast develops relatively well compared with embryos having two female pronuclei. Our combined results indicate that while the paternal genome is essential for the normal development of extraembryonic tissues, the maternal genome may be essential for some stages of embryogenesis. 相似文献
49.
Barton ES White DW Cathelyn JS Brett-McClellan KA Engle M Diamond MS Miller VL Virgin HW 《Nature》2007,447(7142):326-329
All humans become infected with multiple herpesviruses during childhood. After clearance of acute infection, herpesviruses enter a dormant state known as latency. Latency persists for the life of the host and is presumed to be parasitic, as it leaves the individual at risk for subsequent viral reactivation and disease. Here we show that herpesvirus latency also confers a surprising benefit to the host. Mice latently infected with either murine gammaherpesvirus 68 or murine cytomegalovirus, which are genetically highly similar to the human pathogens Epstein-Barr virus and human cytomegalovirus, respectively, are resistant to infection with the bacterial pathogens Listeria monocytogenes and Yersinia pestis. Latency-induced protection is not antigen specific but involves prolonged production of the antiviral cytokine interferon-gamma and systemic activation of macrophages. Latency thereby upregulates the basal activation state of innate immunity against subsequent infections. We speculate that herpesvirus latency may also sculpt the immune response to self and environmental antigens through establishment of a polarized cytokine environment. Thus, whereas the immune evasion capabilities and lifelong persistence of herpesviruses are commonly viewed as solely pathogenic, our data suggest that latency is a symbiotic relationship with immune benefits for the host. 相似文献
50.
Ohinata Y Payer B O'Carroll D Ancelin K Ono Y Sano M Barton SC Obukhanych T Nussenzweig M Tarakhovsky A Saitou M Surani MA 《Nature》2005,436(7048):207-213