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101.
One of the original objectives of the advocacy coalition framework (ACF) was to shed light on the role of science in policymaking. The ACF depicts subsystem scientists as political actors just like any other. Unfortunately, science has never become a major theme of research within the framework and, as a consequence, its role in policymaking remains under‐theorized, leaving ample room for interpretation. This article seeks to explore the validity of three propositions about the role of science in policy. The first two are derived from the ACF: (i) the capacity of scientists to provide credible advice is affected by the harshness of the political debates dividing the policy subsystem; and (ii) agreement among scientists is just as common as among other groupings of policy actors. The third is derived from an “error costs” argument: (iii) Disagreements among scientists are even more pronounced than disagreements among other policy actors. Using the results of a survey of policy actors in 17 biotechnology subsystems, this article finds support for the first and third propositions. Indeed, scientists' participation in political divisions might even be underestimated by the ACF. The article concludes with attempts to clarify the role of scientists within the ACF, including discussions of ambiguity regarding the role of professional forums and of scientists in between‐coalition learning within policy subsystems.  相似文献   
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Heat treatment of lithic raw material is known from the Middle Stone Age to the Neolithic. These findings require archaeometric techniques and methods for detecting the heat‐induced effects within lithic artefacts. However, the existing methods are often cost‐intensive and time‐consuming, and most of them are destructive. Here, we present a new method using the infrared spectroscopic measurement of the strength of H‐bonds formed between surface silanole groups (SiOH) and H2O molecules held in open pores of the samples. The reduction of H‐bond strength in chalcedony is shown to be strongly correlated with the loss of open pores induced by heat treatment. Hence, the method is based on measuring one of the transformations aimed for by the instigators of the heat treatment: the reduction of porosity that modifies the rock's mechanical properties. A first application to heat‐treated material from the Neolithic Chassey culture (southern France) shows that flint was heated to temperatures between 200°C and 250°C in this period. This has important implications for the study of the procedures used and the heating environments. Our new method is non‐destructive, rapid, cost‐effective and allows for detection of the used annealing temperatures.  相似文献   
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Since his mysterious disappearance in 1938, there have been many biographical accounts of Ettore Majorana’s short life. Yet, his scientific work and his influence on the development of physics are often left in the background. The thrust of this article is precisely to shed light on them. In fact, some of Majorana’s articles were only understood after World War II. Notably, this was the case of his last article. Written in 1937, it represents the best long-lasting contribution of Ettore Majorana to particle physics. He envisages, thanks to a new formalism, that neutrinos could be identical to their own antiparticles. The answer to this question posed by Majorana more than half a century ago may be found thanks to several experiments now carried out. It could give a lightning on the nature of dark matter and an explanation to the dominance of matter over antimatter in our universe.  相似文献   
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The transfer of advances in chemometrics into archaeometric research opens up a wide range of new application possibilities in this rapidly developing field. Neutron activation analysis (NAA) of ceramic samples from the Banda Traditional Area (west‐central Ghana) combined with chemometrics allowed us to establish a link between current and ancient systems of ceramics production in the historic settlements of Kuulo Kataa and Makala Kataa. Principal component analysis (PCA) and the soft independent modelling of class analogy (SIMCA) method were applied to the Das Dores Cruz data set in order to unequivocally determine the geographical origin of the diverse archaeological samples. After global autoscaling pretreatment, PCA analysis showed a clear difference between samples from different locations. The classification models obtained by SIMCA showed a classification ability of 100% and a prediction ability of 97.7%, with a mean sensitivity of 84% and a specificity of 100% for the three categories. The application of SIMCA showed that some NAA variables (elements) were more important than others in terms of geographical classification. With the class models that we obtained, we were able to determine the origin of the ancient remains. SIMCA has proved to be a powerful technique for the class modelling of archaeological data.  相似文献   
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Review articles     
Maxence, J.‐L., Les Écrivains sacrifiés des années sida (Bayard, 1997), 139 pp., 100F, ISBN 2 227 304 02 2

Thomé‐Renault, A., Le Traumatisme de la mort annoncée. Psychosomatique et sida (Dunod, 1996), 196 pp., 158F, ISBN 2 10 002488 4  相似文献   
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The computation of constant ductility (or isoductile) response spectra for single-degree-of-freedom systems can require numerous individual response history analyses. Recognising that the same ductility response may be obtained for different strength oscillators of a given period, greater computational effort is required to reduce the possibility that a desired solution is not overlooked. Even a single solution may not exist if a local discontinuity in the strength-ductility relationship coincides with the desired value of ductility. This paper describes a two-phase algorithm to identify the highest strength solution for which the corresponding ductility equals (or does not exceed) the desired ductility. The first phase adopts a “check-reject” approach to reject intervals of strength where the possibility of unidentified higher-strength solutions is considered to be remote, thereby narrowing the strength interval in which the solution will be found. The second phase identifies a solution within this interval as rapidly as possible using a bisection approach. The algorithm is implemented in the USEE software program. The efficiency and accuracy of the algorithm are demonstrated by comparison to results obtained with other software programs.  相似文献   
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