231 research outputs found

    LHC Transverse Feedback System and its Hardware Commissioning

    Get PDF
    A powerful transverse feedback system ("Damper") has been installed in LHC. It will stabilise coupled bunch instabilities in a frequency range from 3 kHz to 20 MHz and at the same time damp injection oscillations originating from steering errors and injection kicker ripple. The transverse damper can also be used as an exciter for purposes of abort gap cleaning or tune measurement. The power and lowlevel systems layouts are described along with results from the hardware commissioning. The achieved performance is compared with earlier predictions and requirements for injection damping and instability control

    Using Data Lake Stack in Animal Sciences

    Get PDF
    Big Data is a theme that receives a lot of attention, and is often characterised as managing and analysing large datasets to reveal new valuable patterns. In the livestock domain, big data is also becoming more common and is being anchored into the mind-set of researchers, due to, for example, sensors generating ..

    The 'Iron Cage' strengthened? Discretion and digital discipline

    Get PDF
    Research on changes in public administration associated with the adoption and use of information and communication technologies ('informatization'), almost univocally supports the conclusion that shop floor discretion disappears under their influence. We, however, are ill at ease with this direction in thought about discretion. Our unease is based on the scholarly work about practices, organizational learning and responsiveness. In this article, we test the thesis on the relation between informatization and operational discretion in an empirical research of operational discretion and informatization in two Dutch public agencies, both large and both automated. Our findings show that informatization does not destroy operational discretion, but rather obscures discretion. Based on the work of Argyris, we show that the phenomenon at work is 'participatory boundary practices', the direct personal ties that keep an organization together. ICTs destroy such links and thereby affect organizational learning. © Blackwell Publishing Ltd. 2007

    LHC Transverse Feedback System: First Results of Commissionning

    Get PDF
    A powerful transverse feedback system ("Damper") has been installed in LHC. It will stabilise the high intensity beam against coupled bunch transverse instabilities in a frequency range from 3 kHz to 20 MHz and at the same time damp injection oscillations originating from steering errors and injection kicker ripple. The LHC Damper can also be used as means of exciting transverse oscillations for the purposes of abort gap cleaning and tune measurement. The LHC Damper includes 4 feedback systems on 2 circulating beams (in other words one feedback system per beam and plane). Every feedback system consists of 4 electrostatic kickers, 4 push-pull wide band power amplifiers, 8 preamplifiers, two digital processing units and 2 beam position monitors with low-level electronics. The power and low-level subsystem layout is described along with first results from the commissioning of 16 power amplifiers and 16 electrostatic kickers located in the LHC tunnel. The achieved performance is compared with earlier predictions and requirements for injection damping and instability control. Requirements and first measurements of the performance of the power and low-level subsystems are summarized

    Jejunal gene expression patterns correlate with severity of systemic infection in chicken

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Not much is known about the effect of <it>Salmonella enteritidis</it> on changes in the developmental processes occurring in the intestine of young chicken. Therefore we investigated the correlation of intestinal gene expression patterns with the severity of systemic Salmonella infections.</p> <p>Methods</p> <p>The number of Salmonella colony forming units (CFUs) in the liver of infected chicken were plotted against the average intestinal expression profiles of previously identified gene expression clusters. The functional properties of all the genes taken together present in 3 clusters exhibiting positive correlation at early time-points were compared with the functional properties of the genes displaying antagonistic correlations in 1 cluster. The top 5 ranking functional groups were analysed in further detail.</p> <p>Results</p> <p>Three clusters showed gene expression profiles which were positively correlated with the severity of systemic disease as measured by the number of Salmonella colony forming units in the liver. In these clusters, genes involved in morphological processes were predominantly present. One cluster had a profile that was negatively correlated with the severity of systemic disease, as measured by numbers of CFUs in the liver. The genes in the latter cluster were mostly involved in cell turn-over and metabolism.</p> <p>Conclusions</p> <p>In the developing jejunum of young chicken, both stimulatory and inhibitory gene expression mechanisms are correlated with the severity of systemic Salmonella infections.</p

    From colostomy creation to full enteral feeding in neonates with an anorectal malformation:evaluating the role of central venous access

    Get PDF
    Purpose: After creating a colostomy in newborns with anorectal malformations (ARMs), reaching full enteral feeding may take longer than expected, resulting in an unanticipated period of starvation. This retrospective cohort study aimed to evaluate the postoperative course regarding enteral feeding tolerance and the necessity for a central venous access device (CVAD) after colostomy formation in newborns with ARMs. Methods: The files of neonates with ARMs who underwent colostomy formation between January 2014 and August 2023 were reviewed. The primary outcome was the postoperative tolerance of enteral feeding. Secondary outcomes were the need for a CVAD and CVAD-related complications. Results: Thirty-four neonates with an ARM underwent colostomy formation. Enteral feeding was initiated on median postoperative day two (IQR 1–2). Full enteral feeding was reached on median postoperative day six (IQR 4–8). In nine neonates (26.5%), it took more than seven postoperative days to reach full enteral feeding, of whom seven (77.8%) had one or more comorbidities that could affect neonatal feeding tolerance. A CVAD was placed in 17 neonates (50%), of whom four (23.5%) needed additional general anesthesia for its placement. There were one or more CVAD-related complications in seven of 17 (41.2%) neonates, mainly involving suspicion of mild catheter-related infections. Conclusions: The majority of neonates undergoing colostomy formation for an ARM require more than five days to achieve full enteral feeding. It is recommended to bridge this period of inadequate feeding with either fluids or parenteral nutrition by inserting a CVAD during colostomy formation, particularly for those with comorbidities affecting neonatal feeding tolerance.</p

    First Results for the Beam Commissioning of the CERN Multi-Turn Extraction

    Get PDF
    The Multi-Turn Extraction (MTE), a new type of extraction based on beam trapping inside stable islands in horizontal phase space, has been commissioned during the 2008 run of the CERN Proton Synchrotron. Both singleand multi-bunch beams with a total intensity up to 1.4 1013 protons have been extracted with efficiencies up to 98%. Furthermore, injection tests in the CERN Super Proton Synchrotron were performed, with the beam then accelerated and extracted to produce neutrinos for the CERN Neutrino-to-Gran Sasso experiments. The results of the extensive measurement campaign are presented and discussed in detail

    Ions for LHC: Towards Completion of the Injector Chain

    Get PDF
    The commissioning of CERN's ion injector complex [1] to allow 1.1 PeV collisions of ions in LHC is well under way. After the Low Energy Ion Ring (LEIR) in 2005 [2] and the Proton Synchrotron (PS) in 2006 [3], the Super Proton Synchrotron (SPS) has now been commissioned with the 'Early' ion beam, which should give a luminosity of 5×1025cm2s15×10^{25}cm^{-2}s^{-1} in the LHC. This paper summarizes the operation in 2007 of all the machines involved in the ion injection chain

    AvBD1 nucleotide polymorphisms, peptide antimicrobial activities and microbial colonisation of the broiler chicken gut

    Get PDF
    Abstract Background The importance of poultry as a global source of protein underpins the chicken genome and associated SNP data as key tools in selecting and breeding healthy robust birds with improved disease resistance. SNPs affecting host peptides involved in the innate defences tend to be rare, but three non-synonymous SNPs in the avian β-defensin (AvBD1) gene encoding the variant peptides NYH, SSY and NYY were identified that segregated specifically to three lines of commercial broiler chickens Line X (LX), Line Y(LY) and Line Z. The impacts of such amino acid changes on peptide antimicrobial properties were analysed in vitro and described in relation to the caecal microbiota and gut health of LX and LY birds. Results Time-kill and radial immune diffusion assays indicated all three peptides to have antimicrobial properties against gram negative and positive bacteria with a hierarchy of NYH > SSY > NYY. Calcein leakage assays supported AvBD1 NYH as the most potent membrane permeabilising agent although no significant differences in secondary structure were identified to explain this. However, distinct claw regions, identified by 3D modelling and proposed to play a key role in microbial membrane attachment, and permeation, were more distinct in the NYH model. In vivo AvBD1 synthesis was detected in the bird gut epithelia. Analyses of the caecal gut microbiota of young day 4 birds suggested trends in Lactobacilli sp. colonisation at days 4 (9% LX vs × 30% LY) and 28 (20% LX vs 12% LY) respectively, but these were not statistically significant (P > 0.05). Conclusion Amino acid changes altering the killing capacity of the AvBD1 peptide were associated with two different bird lines, but such changes did not impact significantly on caecal gut microbiota
    corecore