The Limits of Precaution

The maximin rule can be used as a formal version of the precautionary principle. This paper evaluates the feasibility and the intuitive plausibility of this decision rule. The major conclusions are: (1) Precaution has to be applied symmetrically. (2) Precaution is only possible when outcomes are comparable in terms of value, so that it can be determined which outcome is worst. (3) Precaution is sensitive to standards of possibility. Far-away scenarios have to be excluded, and it is difficult to find a principled way to draw the line. (4) Precaution is sensitive to the framing of decision problems. Local cautiousness may add up to global incautiousness. This revised version was published online in July 2006 with corrections to the Cover Date.     

'On Going Up in the World': Nation,Region and the Land Elevation Debate in Sweden

The aim of the article is to analyse the relationship between Quaternary geology, the idea of land elevation, nationalism and regionalism in Scandinavia, with special regard to the contribution of Swedish geologists at the end of the nineteenth century. From a scientific point of view, the idea of land elevation was connected to the acceptance of the glaciation theory and the elevation theory of Thomas F. Jamieson, but analysed in a wider cultural context it is possible to understand both the professionalization of Quaternary geology and the new theory of shore-line displacement as expressions of Swedish cultural nationalism. As a complement to the specific cultural history, the Quaternary geology enterprise was a way of constituting a unique natural history of the nation. One of the new theories that developed in this process was that of the Highest Marine Border, a complex concept established by the distinguished geologist Gerard De Geer at the end of the 1880s in order to defend the theory of land elevation, which was threatened by the work of Eduard Suess. The line was considered to be a geographical border that both expressed the elevation pattern and sharply divided Sweden into one part that had been covered by water during the post-glacial period and another part that had not. The study continues by looking more closely at the construction of the border in the north of Sweden. Through an account of a subsequent scientific dispute between De Geer and the geologist Arvid Gustaf Hogbom it is clear that the concept of the Highest Marine Border was shaped not only by nationalism but also by regionalism.     

Eight glacial cycles from an Antarctic ice core

The Antarctic Vostok ice core provided compelling evidence of the nature of climate, and of climate feedbacks, over the past 420,000 years. Marine records suggest that the amplitude of climate variability was smaller before that time, but such records are often poorly resolved. Moreover, it is not possible to infer the abundance of greenhouse gases in the atmosphere from marine records. Here we report the recovery of a deep ice core from Dome C, Antarctica, that provides a climate record for the past 740,000 years. For the four most recent glacial cycles, the data agree well with the record from Vostok. The earlier period, between 740,000 and 430,000 years ago, was characterized by less pronounced warmth in interglacial periods in Antarctica, but a higher proportion of each cycle was spent in the warm mode. The transition from glacial to interglacial conditions about 430,000 years ago (Termination V) resembles the transition into the present interglacial period in terms of the magnitude of change in temperatures and greenhouse gases, but there are significant differences in the patterns of change. The interglacial stage following Termination V was exceptionally long--28,000 years compared to, for example, the 12,000 years recorded so far in the present interglacial period. Given the similarities between this earlier warm period and today, our results may imply that without human intervention, a climate similar to the present one would extend well into the future.     

Bi-orientation of achiasmatic chromosomes in meiosis I oocytes contributes to aneuploidy in mice

The spindle assembly checkpoint guards against chromosomal missegregation but does not induce arrest in oocytes that contain a few achiasmatic chromosomes (univalents). We followed the fate of univalents in oocytes during the first meiotic division, and although these preserved a meiotic kinetochore structure, they were also bi-oriented in a mitotic manner. The hybrid chromosomal configuration attained by univalents allows them to evade the spindle assembly checkpoint and contribute to aneuploidy in oocytes.     

Composition and functional role of the mucus layers in the intestine

In discussions on intestinal protection, the protective capacity of mucus has not been very much considered. The progress in the last years in understanding the molecular nature of mucins, the main building blocks of mucus, has, however, changed this. The intestinal enterocytes have their apical surfaces covered by transmembrane mucins and the whole intestinal surface is further covered by mucus, built around the gel-forming mucin MUC2. The mucus of the small intestine has only one layer, whereas the large intestine has a two-layered mucus where the inner, attached layer has a protective function for the intestine, as it is impermeable to the luminal bacteria.     

Common sequence variants on 20q11.22 confer melanoma susceptibility

We conducted a genome-wide association pooling study for cutaneous melanoma and performed validation in samples totaling 2,019 cases and 2,105 controls. Using pooling, we identified a new melanoma risk locus on chromosome 20 (rs910873 and rs1885120), with replication in two further samples (combined P < 1 x 10(-15)). The per allele odds ratio was 1.75 (1.53, 2.01), with evidence for stronger association in early-onset cases.     

Behavioural and electrophysiological evaluation of oviposition attractants forCulex quinquefasciatus say (Diptera: Culicidae)

The attraction of gravidCulex quinquefasciatus by the oviposition pheromone,erythro-6-acetoxy-5-hexadecanolide, and by polluted water is described. Both materials increase oviposition and when combined the effect is additive. The oviposition behaviour is reflected by the antennal sensitivity to these compounds.     

Falsificationism Falsified

A conceptual analysis of falsificationism is performed, in which the central falsificationist thesis is divided into several components. Furthermore, an empirical study of falsification in science is reported, based on the 70 scientific contributions that were published as articles in Nature in 2000. Only one of these articles conformed to the falsificationist recipe for successful science, namely the falsification of a hypothesis that is more accessible to falsification than to verification. It is argued that falsificationism relies on an incorrect view of the nature of scientific inquiry and that it is, therefore, not a tenable research methodology.