Seals at sea: modelling seal distribution in the German bight based on aerial survey data

The Wadden Sea is an important habitat for harbour seals and grey seals. They regularly haul-out on sandbanks and islands along the coast. Comparably little is known about the time seals spend at sea and how they use the remainder of the North Sea. Yet, human activity in offshore waters is increasing and information on seal distribution in the North Sea is crucial for conservation and management. Aerial line transect surveys were conducted in the German bight from 2002 to 2007 to investigate the distribution and abundance of marine mammals. Distance sampling methodology was combined with density surface modelling for a spatially explicit analysis of seal distribution in the German North Sea. Depth and distance to coast were found to be relevant predictor variables for seal density. Density surface modelling allowed for a depiction of seal distribution in the study area as well as an abundance estimate. This is the first study to use aerial survey data to develop a density surface model (DSM) for a spatially explicit distribution estimate of seals at se

Activation of the U2 snRNA promoter by the octamer motif defines a new class of RNA polymerase II enhancer elements

The recent discovery that the activation domains of transcriptional activators (e.g., GAL4) from a number of species are interchangeable has led to the concept of a general mechanism for activation of RNA polymerase II genes. We have examined the different activities of the SV40 octamer motif ATGCAAAG in B cells and in HeLa cells in the context of either the beta-globin promoter, a TATA-box-containing mRNA promoter, or the U2 snRNA promoter, which contains a snRNA-specific proximal element. In the context of the beta-globin promoter, the octamer motif is a B-cell-specific enhancer element, whereas it is a ubiquitous enhancer element for the U2 snRNA promoter. The U2 promoter is unique in that it is not activated by enhancer elements that activate the beta-globin promoter, and a hybrid U2 promoter containing the upstream activating sequence UASG is not stimulated by a yeast GAL4 trans-activator. Together, these observations suggest that in the context of the U2 promoter, the octamer motif defines a new class of RNA polymerase II enhancer elements, which bind transcription factors that trans-activate gene expression by a different mechanism than the general mechanism mentioned above. These results are discussed in light of the possibility that the ubiquitous octamer binding protein Oct-1 and the B-cell-specific octamer binding protein Oct-2 are involved in the activation of the U2 and beta-globin promoters, respectively

Molecular Identification of Lactic Acid Bacteria Occurring in Must and Wine

A specifically amplified polymorphic DNA-polymerase chain reaction (SAPD-PCR), a molecularfingerprinting method based on the amplification of specific gene sequences, was applied in order to allowa rapid identification of lactic acid bacteria (LAB) occurring in must and wine. The applicability of thismethod was confirmed with isolated strains from different wine samples from the German wine growingregion Palatinate. In addition, the formation of biogenic amines by the isolated strains was studied. Morethan half of the bacterial isolates from 50 red and white wine samples were able to produce biogenic amines.General health concerns related to biogenic amines in must and wine underline the need for an identificationof these species. The majority of the isolated strains were assigned to the species Lactobacillus brevis. Themajor biogenic amines in the investigated wines which were detected by thin-layer chromatography andHPLC were tyramine, histamine and ethylamine

Rationale for a Stronger Disposition of Chardonnay Wines for Stuck and Sluggish Fermentation

The aim of this study was to identify and evaluate factors that contribute to fermentation problems inChardonnay, since this variety is reported to have frequent problems. Analytical methods included gaschromatography mass spectrometry, as well as atomic absorption spectroscopy and FT-MIR spectroscopy.Chardonnay, Pinot blanc, Pinot noir and Pinot noir précoce were screened to relate observations to specificvarietal properties. The results show a significant distinction in the amino acid profile of Chardonnay,which can be correlated with sluggish fermentation. A comparison between the fatty acid profile ofChardonnay and Pinot blanc reveals that Chardonnay contains more toxic compounds, which inhibityeast metabolism. Mineral supply and potential metal toxicity were also analysed. The concentrationsof iron, copper, magnesium, zinc and manganese show significant variations among the grape varieties.In conclusion, the possible causes for stuck fermentation in Chardonnay could be more related more tovariety than to oenological decisions

A novel MCF-10A line allowing conditional oncogene expression in 3D culture

Introduction Non-transformed mammary epithelial cell lines such as MCF-10A recapitulate epithelial morphogenesis in three-dimensional (3D) tissue culture by forming acinar structures. They represent an important tool to characterize the biological properties of oncogenes and to model early carcinogenic events. So far, however, these approaches were restricted to cells with constitutive oncogene expression prior to the set-up of 3D cultures. Although very informative, this experimental setting has precluded the analysis of effects caused by sudden oncoprotein expression or withdrawal in established epithelial cultures. Here, we report the establishment and use of a stable MCF-10A cell line (MCF-10Atet) fitted with a novel and improved doxycycline (dox)-regulated expression system allowing the conditional expression of any transgene. Methods MCF-10Atet cells were generated by stable transfection with pWHE644, a vector expressing a second generation tetracycline-regulated transactivator and a novel transcriptional silencer. In order to test the properties of this new repressor/activator switch, MCF-10Atet cells were transfected with a second plasmid, pTET-HABRAF-IRES-GFP, which responds to dox treatment with the production of a bi-cistronic transcript encoding hemagglutinin-tagged B-Raf and green fluorescent protein (GFP). This improved conditional expression system was then characterized in detail in terms of its response to various dox concentrations and exposure times. The plasticity of the phenotype provoked by oncogenic B-RafV600E in MCF-10Atet cells was analyzed in 3D cultures by dox exposure and subsequent wash-out. Results MCF-10Atet cells represent a tightly controlled, conditional gene expression system. Using B-RafV600E as a model oncoprotein, we show that its sudden expression in established 3D cultures results in the loss of acinar organization, the induction of an invasive phenotype and hallmarks of epithelial-to-mesenchymal transition (EMT). Importantly, we show for the first time that this severe transformed phenotype can be reversed by dox wash-out and concomitant termination of oncogene expression. Conclusions Taken together, we have generated a stable MCF-10A subline allowing tight dox-controlled and reversible expression of any transgene without the need to modify its product by introducing artificial dimerization or ligand-binding domains. This system will be very valuable to address phenomena such as EMT, oncogene addiction, oncogene-induced senescence and drug resistance

What did we learn from the extraction experiments with bent crystals at the CERN SPS?

The feasibility and properties of particle extraction from an accelerator by means of a bent crystal were studied extensively at the CERN SPS. The main results of the experiments are presented. This includes the evidence for multipass extraction of heavy ions. These results are compared with theoretical expectations and computer simulations

On the energy dependence of proton beam extraction with a bent crystal

Proton beam extraction from the CERN SPS by means of a bent silicon crystal is reported at three different energies, 14 GeV, 120 GeV and 270 GeV. The experimental results are compared to computer simulations which contain a sound model of the SPS accelerator as well as the channeling phenomena in bent crystals. The overall energy dependence of crystal assisted proton beam extraction is understood and provides the basis to discuss such a scheme for future accelerators

Analysis of Optical Layouts for the Phase 1 upgrade of the CERN Large Hadron Collider Insertion Regions

In the framework of the studies for the upgrade of the insertions of the CERN Large Hadron Collider, four optical layouts were proposed with the aim of reducing the beta-function at the collision point down to 25 cm. The different candidate layouts are presented. Results from the studies performed on mechanical and dynamic aperture are summarized, together with the evaluation of beam-beam effects. Particular emphasis is given to the comparison of the optics performance, which led to retain the most promising layouts for further development

Proton extraction from the CERN SPS using a bent crystal

The extraction of high energy particles from a circular accelerator by means of channeling in bent crystals is an attractive alternative to classical extraction schemes, in particular for high energy proton colliders where a classical scheme becomes expensive and incompatible with normal operation this paper reviews the ongoing extraction experiments at the CERN-SPS with bent silicon crystals. it describes the principles of beam extraction by means of a bent crystal and the different extraction schemes used: firs- and multi-pass extraction and the methods to create diffusion. The limitations in tuning the accelerator to the desired impact parameters and crucial items concerning crystal preparation, bending and pre-alignment are discussed. the experimental procedures including an overview of the detection of circulation and extracted beam are given. Finally the paper summarizes the results of these experiments together with ideas for future developments