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The Et3N-assisted condensation of the ferriomethyl-silanol Cp(OC)2Fe−CH2−SiMe2OH (1) with 1 equiv of Cp2MCl2 (M = Ti (2a), Zr (2b)) leads to the formation of the iron fragment substituted heterosiloxanes Cp(OC)2Fe−CH2−SiMe2O−M(Cl)Cp2 (M = Ti (3a), Zr (3b)). The bis(siloxy) zirconium complex [Cp(OC)2Fe−CH2−SiMe2O]2−ZrCp2 (4) is obtained by further condensation of the M−Cl functionality of 3b with 1. The new compounds have been identified spectroscopically, and in addition, 3b and 4 have been structurally characterized by single-crystal X-ray diffraction methods.

The nucleotide sequence of the HindIII-D fragment of adenovirus type 2 has been determined. The sequence, which is located between coordinates 41.8 and 51.0, covers most of the L2 cotermination family. It includes three major open translational reading frames encoding the carboxyl-terminal part of the penton base as well as the major core polypeptides V and VII. An additional minor open translational reading frame encoding a highly basic polypeptide was detected in the sequence. The L2 region has a very compact organization with very short distances between the different genes, although no overlapping coding sequences were found. The predicted amino acid sequences of core proteins V and VII reveal that they are highly basic proteins and polypeptide VII resembles the arginine-rich H4 histones in its amino acid composition, but no striking similarities are apparent at the amino acid sequence level. The candidate polypeptide encoded by the newly discovered translational reading frame contains 29% basic residues and includes a hypothetical recognition sequence for the adenovirus-encoded endopeptidase. In conjunction with previously published sequences and those reported in accompanying papers (Akusjärvi, G., Aleström, P., Pettersson, M., Lager, M., Jörnvall, H., and Pettersson, U. (1984) J. Biol. Chem. 259, 13976-13979; Roberts, R. J., O'Neill, K. E., and Yen, C. E. (1984) J. Biol. Chem. 259, 13965-13975) a complete sequence can now be reconstructed for the 35,937-base pairs adenovirus type 2 genome.

The nucleotide sequence of the gene for the adenovirus type 2 hexon has been determined. The hexon polypeptide consists of 967 amino acid residues and has a molecular weight of 109,058. Several tentative parts in the previously reported amino acid sequence were resolved from the DNA sequence. The existence of regions with unusual properties in the hexon protein was confirmed, including a region consisting of 16 consecutive acidic residues in the N-terminal part of the protein. In conjunction with previously published sequences and sequences reported in the accompanying papers (Aleström, P., Akusjärvi, G., Lager, M., Yeh-Kai, L., and Petterson, U. (1984) J. Biol. Chem. 259, 13980-13985; Roberts, R. J., O'Neill, K. E., and Yen, C. E. (1984) J. Biol. Chem. 259, 13965-13975) a complete sequence of the 35,937-base pairs-long adenovirus type 2 genome can now be reconstructed.

In north-western Europe, the common tick, Ixodes ricinus, is widely established, its distribution appears to be increasing and the spread of tick-borne diseases is of increasing concern. The project ‘Flått i Nord’(Ticks in northern Norway) commenced in spring 2009 with the intention of studying the tick’s distribution and that of its pathogens in northern Norway. Several methods were used: cloth-dragging, collecting from trapped small mammals, and collecting from pets. Since 2010, the occurrence of ticks in the region of northern Norway was determined directly by cloth-dragging 167 times in 109 separate locations between the latitudes of 64 °N and 70 °N (included seven locations in the northern part of Trøndelag County). The northernmost location of a permanent I. ricinuspopulation was found to be Nordøyvågen (66.2204 °N, 12.59 °E) on the Island of Dønna. In a sample of 518 nymphal and adult ticks, the Borreliaprevalence collected close to this distribution limit varied but was low (1–15 %) compared with the locations in Trøndelag, south of the study area (15–27 %). Five specimens (1 %) were positive for Rickettsia helvetica. The length of the vegetation growing season (GSL) can be used as an approximate index for the presence of established populations of I. ricinus. The present study suggests that the threshold GSL for tick establishment is about 170 days, because the median GSL from 1991 to 2015 was 174–184 days at sites with permanent tick populations, showing a clear increase compared with the period 1961–1990. This apparent manifestation of climate change could explain the northward extension of the range of I. ricinus.