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The paper explores the socially salient contrast between ‘mainlanders' and ‘saltwater people’ in the Buka area in the Autonomous Region of Bougainville, Papua New Guinea, as observed during ethnographic fieldwork in 2004–05. Buka people themselves articulate three at first sight disparate points of contrast between mainlanders and saltwater people. These concern settlement patterns, predominant subsistence activities and different degrees of ancestral knowledge. This paper explores these points and aims to specify their interconnection from the perspective provided by a fourth contrast established ethnographically, that between different modes of objectifying relations on the mainland and ‘at sea’. With a detailed investigation of the ethnographic ‘surface’ of the phenomenon, the paper aims to provide a basis for future in-depth analyses of various aspects of the mainland-saltwater contrast in the context of Bougainvillean politics and the sustainability of livelihoods in the area.

Two series of optically active, cleft-type dendritic receptors (dendroclefts) for carbohydrate recognition were prepared by attaching Frechet-type dendrons via ethynediyl linkers to a core consisting of one or two 1,1′-binaphthalene-2,2′-diyl phosphate moieties. Sugar substrates were expected to bind via bidentate ionic H-bonding of two OH groups to the phosphodiester core and, additionally, to undergo van der Waals and CH⋅⋅⋅π interactions with the aromatic rings of the surrounding dendritic wedges. The synthesis of the dendritic receptors G-1-(S)-1, G-2-(S)-2, and G-3-(S)-3 (Fig. 1; G-x=dendritic generation) with a single binaphthalene core started from 3,3′-diethynylated MOM-protected (MOM=methoxymethyl) 1,1′-binaphthalene-2,2′-diol (S)-13 to which the Frechet-type dendrons of generations 1 – 3 were attached via Sonogashira cross-coupling (Scheme 3). MOM-Ether deprotection followed by phosphodiester formation and ion exchange provided the targeted receptors. By a similar route, receptor G-1-(S)-23 with dendritic wedges capped with oligoether groups was obtained (Scheme 4). In receptor G-1-(S)-26, the ethynediyl linker was omitted, and, in its synthesis, the dendritic wedges were attached to MOM-protected 3,3′-diiodo-1,1′-binaphthalene-2,2′-diol by Suzuki cross-coupling (Scheme 5). The synthesis of the dendritic receptors G-2-(S,S)-42 and G-1-(S,S)-43 with two binaphthalene moieties at the core (Fig. 3) started from diethynylated (S,S)-39 and (S,S)-33, which contain two MOM-protected 1,1′-binaphthalene-2,2′-diol moieties bridged by p-phenylene or buta-1,3-diynediyl linkers, respectively, and was completed by attachment of the dendritic wedges by Sonogashira coupling, MOM-ether deprotection, phosphodiester formation, and ion exchange (Schemes 9 and 10). By an alternative route, the C-frame of receptor G-2-(S,S)-41 was prepared by coupling the dendron to dialkynylated 1,1′-binaphthalene (S)-44, followed by oxidative Glaser-Hay coupling (Scheme 8). For control studies, the non-dendritic reference receptors (S)-4 and (S)-5 (Fig. 1) with one and (S,S)-31 and (S,S)-32 (Fig. 2) with two 1,1′-binaphthalene-2,2′-diyl phosphate moieties were also prepared. 1H-NMR Complexation studies with the dendritic receptors containing one binaphthalene core and octyl glycosides 53 – 55 in CD3CN and CDCl3 (Tables 2 – 4) revealed that ionic H-bonding between the phosphodiester core in the dendritic receptors and the sugar OH groups provides the major driving force for stoichiometric 1 : 1 host-guest association. A smaller, yet significant contribution to the binding free enthalpy was also provided by interactions between the sugar guests and the dendritic wedges. Binding selectivity was weak in all cases, and only small changes in association strength were observed as a function of dendritic generation. In studies with the dendritic receptors, which contain two binaphthalene moieties at the core, higher-order complex stoichiometries prevented the determination of quantitative binding data. As a result of unfavorable steric interactions between the dendritic wedges, these flexible receptor systems apparently avoid adopting the `syn'-conformation with convergent phosphodiester sites that is required for efficient 1 : 1 host-guest complexation.

The resurrection plant Craterostigma plantagineum tolerates an extreme loss of cellular water. Therefore this plant is being studied as model system to analyse desiccation tolerance at the molecular level. Upon dehydration, new transcripts are abundantly expressed in different tissues of the plant. One such desiccation-related nuclear gene (dsp-22 for desiccation stress protein) encodes a mature 21 kDa protein which accumulates in the chloroplasts. Sequence analysis indicates that dsp-22 is closely related to early light inducible genes (Elip) of higher plants and to a carotene biosynthesis related gene (cbr) isolated from the green alga Dunaliella bardawil. In contrast to other desiccation-related genes, light is an essential positive factor regulating the expression of dsp-22: ABA-mediated gene activation leads to the accumulation of the transcript only in the presence of light. During the desiccation process, light acts at the transcriptional and post-transcriptional levels. The implications of these different controls and the possible role of the dsp-22 protein in the desiccation/rehydration process are discussed.

An integrated approach involving EST sequencing, data mining and multiparallel expression profiling by macroarray analysis was established to classify sugar beet gene products with respect to their expression in three different organs. The DNA sequences of 2996 ESTs derived from young sugar beet plants specified 2048 unique gene products with putative functions in primary and secondary metabolism (651), transport processes (136), signal transduction (78) and cellular organization (39). The cDNA clone collection was the basis for the generation of a macroarray. Sensitivity and reproducibility of our macroarray hybridization procedure were estimated first. The detection limit was found to correspond to 10 - 50 copies of single transcripts per cell. Within an interval of two-fold variation in signal intensities, reproducibility between spots on the same filter was determined to be 98.9 %, between spots on different filters 89.8 %, and reproducibility after hybridization with two probes synthesized from the same poly(A)+RNA sample was 97.6 %. Expression profiles from roots, leaves and inflorescences of field-grown plant material were generated. Two different samples of each organ were analysed to reduce sampling effects, which accounted on average for 30.3 % of spots with at least two-fold deviation. Expression values for each organ were determined by a stringent statistical evaluation of eight hybridizations for each clone. Macroarray expression data were confirmed by Northern blot analysis and quantitative RT-PCR experiments concerning eleven cDNAs. The analysis was then focused on 76 unique cDNAs, for which the amount of detected transcript in roots was at least twice as high as in the other organs tested. Functions of preferentially root-expressed candidate genes in taproot morphology and physiology are discussed