Rapid physiological assays for nutrient demand by the plankton. II. Phosphorus

Four bioassays for phosphorus demand were compared. ³²P-turnoverrates provided an integrated measure of transport capacity ofthe assemblage and ambient orthophosphate levels, but rateswere often not simply exponential and could not be accuratelyquantified by a single rate constant. ATP responses to phosphorusenrichment were transient and they poorly separated naturalplankton populations with very different degrees of P-deficiency.Alkaline phosphatase activity corresponded well with other measuresof phosphorus demand although low activities did not necessarilyimply non-limiting phosphorus conditions. Selective luxury accumulationof N and P by the seston from an N + P enrichment provided themost informative guide to the relative demand for the two elements.No single approach could be considered conclusive on its own,but in combination the assays provided a reliable measure ofphosphorus demand and deficiency within natural assemblagesof plankton.     

Metabolic compensation activates pro-survival mTORC1 signaling upon 3-phosphoglycerate dehydrogenase inhibition in osteosarcoma

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MeMo: a hybrid SQL/XML approach to metabolomic data management for functional genomics

Background  

The genome sequencing projects have shown our limited knowledge regarding gene function, e.g. S. cerevisiae has 5–6,000 genes of which nearly 1,000 have an uncertain function. Their gross influence on the behaviour of the cell can be observed using large-scale metabolomic studies. The metabolomic data produced need to be structured and annotated in a machine-usable form to facilitate the exploration of the hidden links between the genes and their functions.     

EATB Donor Case Workshop 2007

The European Association of Tissue Banks (EATB) Donor Case Workshop is a forum held within the programme of the EATB annual Congress since 2003. This workshop has been used to discuss clinical donor cases with peer review of practice. It was agreed in advance that the experience of the 2007 workshop should be shared by publication as an example of participative learning which can be extended to other fields within tissue banking and which may be applicable in other disciplines. The EATB Congress in 2008 will extend the idea of participative open workshops with two additional workshops, one on Quality System cases and another on heart valve cases.     

An analysis of fish community responses to coral mining in the Maldives

Synopsis Coral mining takes place on shallow reef flats at a number of localities in the Maldives, but not on the adjacent deeper reef slopes. A semi-quantitative census method for fish species abundance and biomass is described. Fish community structure is compared on mined and non-mined reef flats and their adjacent slopes using a variety of univariate, graphical/distributional and multivariate statistical techniques. In general, univariate and graphical distributional methods do not indicate significant differences between mined and non-mined localities with respect to the relative abundances and biomasses of species. Multivariate methods (both classification and ordination), however, indicate very clear-cut effects of mining on the reef flats, and also significant effects on reef slopes adjacent to mined flats. The effect was equally clear using non-quantitative (presence/absence) data. The fish species mainly responsible for the differences between mined and non-mined localities are identified, and the differences are explained in terms of the feeding biology of these species.     

Species size distributions in Arctic benthic communities

In most subtidal soft-sediment faunal assemblages there is a trough in the species size distribution separating the macrofauna and meiofauna. To examine the hypothesis that this may be maintained by the avoidance of competition between macrofaunal adults and settling larvae, samples were taken from around Svalbard, an area where most macrofaunal species have either lecithotrophic or direct development. At three contrasting sites, bimodality of the species size spectrum was conserved. However, it is proposed that the adult-larval interaction hypothesis should not be rejected as low endemism in the fauna of the study area suggests its species size spectrum probably reflects evolutionary processes outside rather than within the Arctic. Received: 13 May 1996/Accepted: 26 July 1996