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31.
The objective of this paper is to balance two major conceptual tendencies in science policy studies, continuity and discontinuity
theory. While the latter argue for fundamental and distinct changes in science policy in the late 20th century, continuity
theorists show how changes do occur but not as abrupt and fundamental as discontinuity theorists suggests. As a point of departure,
we will elaborate a typology of scientific governance developed by Hagendijk and Irwin (2006) and apply it to new empirical material. This makes possible a contextualization of the governance of science related to
the codification of the “third assignment” of the Swedish higher education law of 1977. The law defined the relation between
university science and Swedish citizens as a dissemination project, and did so despite that several earlier initiatives actually
went well beyond such a narrow conceptualisation. Our material reveals continuous interactive and rival arrangements linking
the state, public authorities, the universities and private industrial enterprises. We show how different but coexisting modes
of governance of science existed in Sweden during the 20th century, in clear contrast with the picture promoted by discontinuity
theorists. A close study of the historical development suggests that there were several periods of layered governance when
interactions and dynamics associated with continuity as well as discontinuity theories were prevalent. In addition, we conclude
that the typology of governance applied in the present paper is fruitful for carrying out historical analyses of the kind
embarked upon in spite of certain methodological shortcomings. 相似文献
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The effective migration of amoeboid cells requires a fine regulation of cell-substratum adhesion. These entwined processes have been shown to be regulated by a host of biophysical and biochemical cues. Here, we reveal the pivotal role played by calcium-based mechanosensation in the active regulation of adhesion resulting in a high migratory adaptability. Using mechanotactically driven Dictyostelium discoideum amoebae, we uncover the existence of optimal mechanosensitive conditions—corresponding to specific levels of extracellular calcium—for persistent directional migration over physicochemically different substrates. When these optimal mechanosensitive conditions are met, noticeable enhancement in cell migration directionality and speed is achieved, yet with significant differences among the different substrates. In the same narrow range of calcium concentrations that yields optimal cellular mechanosensory activity, we uncovered an absolute minimum in cell-substratum adhesion activity, for all considered substrates, with differences in adhesion strength among them amplified. The blocking of the mechanosensitive ion channels with gadolinium—i.e., the inhibition of the primary mechanosensory apparatus—hampers the active reduction in substrate adhesion, thereby leading to the same undifferentiated and drastically reduced directed migratory response. The adaptive behavioral responses of Dictyostelium cells sensitive to substrates with varying physicochemical properties suggest the possibility of novel surface analyses based on the mechanobiological ability of mechanosensitive and guidable cells to probe substrates at the nanometer-to-micrometer level. 相似文献
37.
Grant Clayton Christina Clayton Dick M. Carpenter III Gregory B. Ecks 《Journal of School Choice》2019,13(1):58-75
This study uses administrative data to measure the effect of attending a charter school in Denver, Colorado on the achievement of reclassified English as New Language (ENL) students during their monitor period in the mainstream classroom environment. We utilize school choice data from Denver’s Common Enrollment System (CES) to control for each school a family selected entering grade six, a typical time for a structural move, in order to better control of unobserved variable bias. Results indicate charter attendance increases achievement in mathematics and English on state testing. Charter school success in the CES environment provides insights for districts serving large numbers of ENL students. 相似文献
38.
Latendresse SJ Bates JE Goodnight JA Lansford JE Budde JP Goate A Dodge KA Pettit GS Dick DM 《Child development》2011,82(6):1797-1814
The present study characterized prototypical patterns of development in self-reported externalizing behavior, between 12 and 22 years of age, within a community sample of 452 genotyped individuals. A Caucasian subset (n = 378) was then examined to determine whether their probabilities of displaying discrete trajectories were differentially associated with CHRM2, a gene implicated in self-regulatory processes across a range of externalizing behaviors, and if affiliating with antisocial peers moderated these associations. Findings indicate that relative to a normative "lower risk" externalizing trajectory, likelihood of membership in two "higher risk" trajectories increased with each additional copy of the minor allelic variant at CHRM2, and that this association was exacerbated among those exposed to higher levels of peer group antisocial behavior. 相似文献
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Jack Lyle Ken Coleman Joseph Fletcher Littell Joseph Julian Dick Cavett Christopher Porterfield 《Communication Booknotes Quarterly》2013,44(10):113-114
Jack Lyle's The People Look at Public Television: 1974 (Washington: Corporation for Public Broadcasting, 1975—$1.00, paper) Ken Coleman's So You Want to be a Sportscaster (New York: Hawthron Books, 1973—$5.95) Joseph Fletcher Littell (ed.) Coping with Television (Evanston, Ill.: McDougal, Littell, 1973— cost not given, paper) Joseph Julian's This Was Radio: A Personal Memoir (New York: Viking, 1975—$8.85) Dick Cavett and Christopher Porterfield's Cavett (New York: Harcourt, Brace Jevanovich, 1974—$8.95) 相似文献