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The topographic relation of the spine to the great vessels let to the expectation that spondylolisthesis may lead to mechanical irritation of the cauda equina as well as of the great vessels. The angiological examination of 223 patients with spondylolisthesis of the lumbar spine shows that the changes in the anatomy of the great vessels are less significant than expected after experiments involving artificial dislocations of the spine in cadavers. In vivo arterial function is not altered even in true spondyloptosis. Pelvic veins on the other hand show considerable compression and diminished flow in third and fourth degree spondylolisthesis of L5 over S1 as well as in second degree spondylolishtesis of L4 over L5. These patients seem to be disposed to venous disorders involving varices and thrombosis. If therefore a high venous pressure is found and a ventral fusion proposed it should be discussed to combine the procedure with a decompression of the veins.

Arctic sea ice is declining rapidly in extent and thickness, simplifying access to oil and gas fields, enabling trans-Arctic shipping and allowing storms to erode permafrost coasts. This in turn modifies the biogeochemical cycling of carbon and nutrients, intensifies land-ocean interactions, as well as it shifts the distribution of harvestable resources. Alarmingly, sea ice reductions are taking place more rapidly than predicted in any global climate model. This persistent mismatch between observed and predicted patterns makes planning activities in the Arctic challenging. Scientific knowledge of the evolving status of the Arctic Ocean, its surrounding land areas and the process-based understanding of the mechanics of change are urgently needed to make useful projections of future conditions throughout the Arctic region. Arctic in Rapid Transition (ART; http://www.iarc.uaf.edu/en/ART/) is an integrative, international, interdisciplinary, pan-Arctic network to study the spatial and temporal changes in biogeochemical cycling and ecosystem functions in the Arctic marine and coastal realm. ART has been developed and is still steered by early-career scientists. Since 2012 it is an official network of the International Arctic Science Committee (IASC). The first phase of ART (2010-2014) focuses on developing a formal network to bring together scientists working in different geographic and disciplinary areas who share a common interest in improving our understanding of Arctic change. An ART Science Workshop will be held 21-24 October 2014 in Plouzané, France, in collaboration with the Association of Polar Early Career Scientists (APECS), the Permafrost Young Researchers Network (PYRN) and the European Institute for Marine Studies. This international workshop entitled “Integrating spatial and temporal scales in the changing Arctic System: towards future research priorities” (ISTAS) will aim at drafting research priorities from an early to mid-career perspective that will feed into the third International Conference on Arctic Research Planning (ICARP III) in Toyama, Japan in 2015. This workshop will bring together about 60 early career, mid-career and senior scientists from different Arctic research areas including cryosphere, terrestrial, marine, atmosphere, and socio-economic topics to ensure knowledge transfer across generations and disciplines. The second phase of ART (2014-2018) will be centered on active data collection, such as through the TRANSSIZ expedition planned on the RV ‘Polarstern’ in 2015. The final phase of ART will be a synthesis stage, so that the legacy of ART will be a coherent set of knowledge, which would feed into physical-biological models at various scales in order to develop more robust scenarios regarding the future state of Arctic coastal and marine ecosystems, their productive capacity, how they impact the dynamics of greenhouse gases, as well as their role in global processes.

Endo cellulases of plant pathogenic erwinias degrade cellulose as well as the cellulosic domains of barley (1-3,1-4)-beta-glucan. Depolymerization of the latter substrate is mainly caused by (1-3,1-4)-beta-glucanases, which hydrolyze (1-4)-beta glycosidic linkages adjacent to (1-3)-beta linkages. To construct an enzyme for efficient degradation of barley (1-3,1-4)-beta-glucan, the sequence encoding the catalytic domain and interdomain linker of the cellulase from Erwinia carotovora subspecies atroseptica was fused to that for the heat stable Bacillus hybrid, H(A12-M) delta Y13 (1-3,1-4)-beta glucanase. The chimeric enzyme secreted from Escherichia coli cells did not remain covalently assembled as judged by SDS-PAGE. However, the glycosylated and intact enzyme (denoted CELGLU) is secreted from the yeast Pichia pastoris. CELGLU exhibits both cellulase and (1-3,1-4)-beta-glucanase catalytic activities, and was accordingly classified a true multienzyme. HPLC and NMR analyses revealed that among the products from CELGLU, di- and trimeric oligosaccharides were identical to those produced by the parental cellulase. Tetrameric oligosaccharides, derived from the (1-3,1-4)-beta-glucanase activity of CELGLU, were further degraded by the cellulase moiety to yield glucose and trimers. Compared with the parental enzymes, CELGLU exhibits substantially higher Vmax for degradation of both soluble cellulose and barley (1-3,1-4)-beta-glucan. These findings point to construction of multienzymes as an effective approach for engineering enzymes with novel characteristics.

Alfalfa-nodulating rhizobia from acidic soils (pH 5.52-6.2) in Argentina comprise a distinct group of acid-tolerant Rhizobium isolates which were found to be related to Rhizobium sp. strain Or 191 (Del Papa et al., 1999). Lipopolysaccharide profiles and 16S rDNA sequences demonstrated that all twelve acid-tolerant Rhizobium isolates belonged to one species. Furthermore, the group of acid-tolerant Rhizobium isolates was formed by one strain type, since they gave the same plasmid profile as well as the same IS- and ERIC-fingerprints. All acid-tolerant Rhizobium isolates were genetically identical even though they were isolated at very different locations in Argentina. The isolates nodulated a range of Medicago, Melilotus and Trigonella species, and Phaseolus vulgaris, but were weak in nitrogen fixation. M. sativa nodules induced by one of the acid-tolerant rhizobial isolates contained several bacteroids within a vesicle-like structure, in contrast to nodules induced by the reference strain S. meliloti 2011. Reisolation of bacteria from root nodules resulted in approx. 40 times more colony forming bacteria in case of the acid-tolerant strains. These strains mark the borderline between a symbiotic and a parasitic plant-microbe interaction.