A slow gravity compensated Atom Laser

We report on a slow guided atom laser beam outcoupled from a Bose-Einstein condensate of 87Rb atoms in a hybrid trap. The acceleration of the atom laser beam can be controlled by compensating the gravitational acceleration and we reach residual accelerations as low as 0.0027 g. The outcoupling mechanism allows for the production of a constant flux of 4.5x10^6 atoms per second and due to transverse guiding we obtain an upper limit for the mean beam width of 4.6 \mu\m. The transverse velocity spread is only 0.2 mm/s and thus an upper limit for the beam quality parameter is M^2=2.5. We demonstrate the potential of the long interrogation times available with this atom laser beam by measuring the trap frequency in a single measurement. The small beam width together with the long evolution and interrogation time makes this atom laser beam a promising tool for continuous interferometric measurements.Comment: 7 pages, 8 figures, to be published in Applied Physics

Characterization of novel isoforms and evaluation of SNF2L/SMARCA1 as a candidate gene for X-linked mental retardation in 12 families linked to Xq25-26

<p>Abstract</p> <p>Background</p> <p>Mutations in genes whose products modify chromatin structure have been recognized as a cause of X-linked mental retardation (XLMR). These genes encode proteins that regulate DNA methylation (<it>MeCP2</it>), modify histones (<it>RSK2 </it>and <it>JARID1C</it>), and remodel nucleosomes through ATP hydrolysis (<it>ATRX</it>). Thus, genes encoding other chromatin modifying proteins should also be considered as disease candidate genes. In this work, we have characterized the <it>SNF2L </it>gene, encoding an ATP-dependent chromatin remodeling protein of the ISWI family, and sequenced the gene in patients from 12 XLMR families linked to Xq25-26.</p> <p>Methods</p> <p>We used an <it>in silico </it>and RT-PCR approach to fully characterize specific SNF2L isoforms. Mutation screening was performed in 12 patients from individual families with syndromic or non-syndromic XLMR. We sequenced each of the 25 exons encompassing the entire coding region, complete 5' and 3' untranslated regions, and consensus splice-sites.</p> <p>Results</p> <p>The <it>SNF2L </it>gene spans 77 kb and is encoded by 25 exons that undergo alternate splicing to generate several distinct transcripts. Specific isoforms are generated through the alternate use of exons 1 and 13, and by the use of alternate donor splice sites within exon 24. Alternate splicing within exon 24 removes a NLS sequence and alters the subcellular distribution of the SNF2L protein. We identified 3 single nucleotide polymorphisms but no mutations in our 12 patients.</p> <p>Conclusion</p> <p>Our results demonstrate that there are numerous splice variants of SNF2L that are expressed in multiple cell types and which alter subcellular localization and function. <it>SNF2L </it>mutations are not a cause of XLMR in our cohort of patients, although we cannot exclude the possibility that regulatory mutations might exist. Nonetheless, <it>SNF2L </it>remains a candidate for XLMR localized to Xq25-26, including the Shashi XLMR syndrome.</p

Characterization of novel isoforms and evaluation of SNF2L/SMARCA1 as a candidate gene for X-linked mental retardation in 12 families linked to Xq25-26

<p>Abstract</p> <p>Background</p> <p>Mutations in genes whose products modify chromatin structure have been recognized as a cause of X-linked mental retardation (XLMR). These genes encode proteins that regulate DNA methylation (<it>MeCP2</it>), modify histones (<it>RSK2 </it>and <it>JARID1C</it>), and remodel nucleosomes through ATP hydrolysis (<it>ATRX</it>). Thus, genes encoding other chromatin modifying proteins should also be considered as disease candidate genes. In this work, we have characterized the <it>SNF2L </it>gene, encoding an ATP-dependent chromatin remodeling protein of the ISWI family, and sequenced the gene in patients from 12 XLMR families linked to Xq25-26.</p> <p>Methods</p> <p>We used an <it>in silico </it>and RT-PCR approach to fully characterize specific SNF2L isoforms. Mutation screening was performed in 12 patients from individual families with syndromic or non-syndromic XLMR. We sequenced each of the 25 exons encompassing the entire coding region, complete 5' and 3' untranslated regions, and consensus splice-sites.</p> <p>Results</p> <p>The <it>SNF2L </it>gene spans 77 kb and is encoded by 25 exons that undergo alternate splicing to generate several distinct transcripts. Specific isoforms are generated through the alternate use of exons 1 and 13, and by the use of alternate donor splice sites within exon 24. Alternate splicing within exon 24 removes a NLS sequence and alters the subcellular distribution of the SNF2L protein. We identified 3 single nucleotide polymorphisms but no mutations in our 12 patients.</p> <p>Conclusion</p> <p>Our results demonstrate that there are numerous splice variants of SNF2L that are expressed in multiple cell types and which alter subcellular localization and function. <it>SNF2L </it>mutations are not a cause of XLMR in our cohort of patients, although we cannot exclude the possibility that regulatory mutations might exist. Nonetheless, <it>SNF2L </it>remains a candidate for XLMR localized to Xq25-26, including the Shashi XLMR syndrome.</p

A next generation, pilot-scale continuous sterilization system for fermentation media

A new continuous sterilization system was designed, constructed, started up, and qualified for media sterilization for secondary metabolite cultivations, bioconversions, and enzyme production. An existing Honeywell Total Distributed Control 3000-based control system was extended using redundant High performance Process Manager controllers for 98 I/O (input/output) points. This new equipment was retrofitted into an industrial research fermentation pilot plant, designed and constructed in the early 1980s. Design strategies of this new continuous sterilizer system and the expanded control system are described and compared with the literature (including dairy and bio-waste inactivation applications) and the weaknesses of the prior installation for expected effectiveness. In addition, the reasoning behind selection of some of these improved features has been incorporated. Examples of enhancements adopted include sanitary heat exchanger (HEX) design, incorporation of a “flash” cooling HEX, on-line calculation of F(o) and R(o), and use of field I/O modules located near the vessel to permit low-cost addition of new instrumentation. Sterilizer performance also was characterized over the expected range of operating conditions. Differences between design and observed temperature, pressure, and other profiles were quantified and investigated

La crue de l'Ouvèze du 22 septembre 1992 : quantification du phénomène, analyse en terme de période de retour et réflexions sur la prise en compte des risques

This article is a summary of the survey conducted to analyze the September 22, 1992 flood of the Ouvèze watershed. A brief summary of the watershed and the flood is followed by the analysis done using data available to quantify this phenomenon. An estimation in terms of flow is given. The estimation of return periods rely on an additional hydrological survey. / L'article présente un résumé de l'expertise effectuée pour analyser en détail la crue du 22 septembre 1992 sur le bassin versant de l'Ouvèze. Un bref descriptif du bassin versant et de la crue catastrophique est suivi par l'analyse qui a pu être faite sur la base de données disponibles pour quantifier le phénomène. Une estimation du phénomène en terme de débit est donnée. L'estimation des périodes de retour repose sur une étude hydrologique complémentaire

Bassin de l'Ouvèze : analyse de la crue du 22 septembre 1992

The results of the survey on the September 22, 1992 flood of the Ouvèze basin are presented in this article. / L'article présente le résultat de l'étude d'expertise de la crue du 22 septembre 1992 sur le bassin de l'Ouvèze

Optimising food process and formulation on internet: the SYM'PREVIUS experience

International audienceThe Sym’Previus network started in 1999. Sym’Previus meets the French expertise in Predictive Microbiology of major food companies, technical centres and public research institute. This project aims at proposing an assisting tool in the management of food safety. The following dual (software) background is applied: firstly, a database where information on the behaviour of microorganisms in/on foods and natural contamination of foods are structured. A query system, called MIEL, specifically developed for the database, allows to formulate specific interrogation with a specific selection of food and microorganisms. Secondly, a user-friendly software simulates the growth of microorganisms in food matrix. Sym’Previus is a simpler access to predictive microbiology for food companies. At the present time the software describes the effects of temperature, pH and water activity on bacteria growth in a range of food commodities, such as cereals, egg products, dairy product, meat... Sym’Previus is available on www.symprevius.org

Mechanistic model coupling gas exchange dynamics and Listeria monocytogenes growth in modified atmosphere packaging of non respiring food

A mechanistic model coupling O-2 and CO2 mass transfer (namely diffusion and solubilisation in the food itself and permeation through the packaging material) to microbial growth models was developed aiming at predicting the shelf life of modified atmosphere packaging (MAP) systems. It was experimentally validated on a non-respiring food by investigating concomitantly the O-2/CO2 partial pressure in packaging headspace and the growth of Listeria monocytogenes (average microbial count) within the food sample. A sensitivity analysis has revealed that the reliability of the prediction by this "super-parametrized" model (no less than 47 parameters were required for running one simulation) was strongly dependent on the accuracy of the microbial input parameters. Once validated, this model was used to decipher the role of O-2/CO2 mass transfer on microbial growth and as a MAP design tool: an example of MAP dimensioning was provided in this paper as a proof of concept. (C) 2015 Elsevier Ltd. All rights reserved

Suppression of the “notch effect” in microwave surface resistance in

RHEED controlled ultra-thin buffer layers of SrTiO3 have been deposited on (100) MgO by pulsed laser deposition to growth YBaCuO films for microwave applications. A buffer layer with a thickness between 2 and 15 nm, i.e. 5 to 40 unit cells of SrTiO3, is sufficient to expand to more than 60 °C the range of deposition temperatures leading to low microwave surface resistance. The Rs values are as good as those obtained on LaAlO3 substrates with a slighly lower magnetic field dependency. The SrTiO3 seed layer induces an oriented epitaxial growth with YBCO [100] // MgO [100] over this range of deposition temperatures