33 research outputs found

    Relativistic quantum clocks

    Full text link
    The conflict between quantum theory and the theory of relativity is exemplified in their treatment of time. We examine the ways in which their conceptions differ, and describe a semiclassical clock model combining elements of both theories. The results obtained with this clock model in flat spacetime are reviewed, and the problem of generalizing the model to curved spacetime is discussed, before briefly describing an experimental setup which could be used to test of the model. Taking an operationalist view, where time is that which is measured by a clock, we discuss the conclusions that can be drawn from these results, and what clues they contain for a full quantum relativistic theory of time.Comment: 12 pages, 4 figures. Invited contribution for the proceedings for "Workshop on Time in Physics" Zurich 201

    Invasive Group B Streptococcus Disease With Recurrence and in Multiples: Towards a Better Understanding of GBS Late-Onset Sepsis.

    Get PDF
    Group B Streptococcus (GBS) is a common intestinal colonizer during the neonatal period, but also may cause late-onset sepsis or meningitis in up to 0.5% of otherwise healthy colonized infants after day 3 of life. Transmission routes and risk factors of this late-onset form of invasive GBS disease (iGBS) are not fully understood. Cases of iGBS with recurrence (n=25) and those occurring in parallel in twins/triplets (n=32) from the UK and Ireland (national surveillance study 2014/15) and from Germany and Switzerland (retrospective case collection) were analyzed to unravel shared (in affected multiples) or fixed (in recurrent disease) risk factors for GBS disease. The risk of iGBS among infants from multiple births was high (17%), if one infant had already developed GBS disease. The interval of onset of iGBS between siblings was 4.5 days and in recurrent cases 12.5 days. Disturbances of the individual microbiome, including persistence of infectious foci are suggested e.g. by high usage of perinatal antibiotics in mothers of affected multiples, and by the association of an increased risk of recurrence with a short term of antibiotics [aOR 4.2 (1.3-14.2), P=0.02]. Identical GBS serotypes in both recurrent infections and concurrently infected multiples might indicate a failed microbiome integration of GBS strains that are generally regarded as commensals in healthy infants. The dynamics of recurrent GBS infections or concurrent infections in multiples suggest individual patterns of exposure and fluctuations in host immunity, causing failure of natural niche occupation

    Identification of regulatory variants associated with genetic susceptibility to meningococcal disease

    Get PDF
    Non-coding genetic variants play an important role in driving susceptibility to complex diseases but their characterization remains challenging. Here, we employed a novel approach to interrogate the genetic risk of such polymorphisms in a more systematic way by targeting specific regulatory regions relevant for the phenotype studied. We applied this method to meningococcal disease susceptibility, using the DNA binding pattern of RELA - a NF-kB subunit, master regulator of the response to infection - under bacterial stimuli in nasopharyngeal epithelial cells. We designed a custom panel to cover these RELA binding sites and used it for targeted sequencing in cases and controls. Variant calling and association analysis were performed followed by validation of candidate polymorphisms by genotyping in three independent cohorts. We identified two new polymorphisms, rs4823231 and rs11913168, showing signs of association with meningococcal disease susceptibility. In addition, using our genomic data as well as publicly available resources, we found evidences for these SNPs to have potential regulatory effects on ATXN10 and LIF genes respectively. The variants and related candidate genes are relevant for infectious diseases and may have important contribution for meningococcal disease pathology. Finally, we described a novel genetic association approach that could be applied to other phenotypes

    Identification of regulatory variants associated with genetic susceptibility to meningococcal disease.

    Get PDF
    Non-coding genetic variants play an important role in driving susceptibility to complex diseases but their characterization remains challenging. Here, we employed a novel approach to interrogate the genetic risk of such polymorphisms in a more systematic way by targeting specific regulatory regions relevant for the phenotype studied. We applied this method to meningococcal disease susceptibility, using the DNA binding pattern of RELA - a NF-kB subunit, master regulator of the response to infection - under bacterial stimuli in nasopharyngeal epithelial cells. We designed a custom panel to cover these RELA binding sites and used it for targeted sequencing in cases and controls. Variant calling and association analysis were performed followed by validation of candidate polymorphisms by genotyping in three independent cohorts. We identified two new polymorphisms, rs4823231 and rs11913168, showing signs of association with meningococcal disease susceptibility. In addition, using our genomic data as well as publicly available resources, we found evidences for these SNPs to have potential regulatory effects on ATXN10 and LIF genes respectively. The variants and related candidate genes are relevant for infectious diseases and may have important contribution for meningococcal disease pathology. Finally, we described a novel genetic association approach that could be applied to other phenotypes

    Erworbener Chylothorax im Säuglingsalter

    No full text
    <jats:title>Zusammenfassung</jats:title><jats:p>Es wird über den Fall eines 8‑monatigen Säuglings mit einem Chylothorax unklarer Genese berichtet. Ein Stridor, zunehmende respiratorische Beeinträchtigung und, bedingt durch den hohen Eiweißverlust, ausgeprägte Ödeme waren die relevantesten klinischen Merkmale. Die bekannten konservativen Therapien wie fettfreie enterale Ernährung unter Substitution von „medium-chain triglycerides“(MCT)-Fetten, gefolgt von Nahrungskarenz und parenteraler Ernährung sowie die Gabe des Somatostatinanalogons Octreotid konnten trotz langer Therapiedauer keine Besserung erzielen. Erst der Einsatz von thorakoskopisch eingebrachten Titan-Clips brachte letztlich den gewünschten Erfolg.</jats:p&gt

    Electronic Bridge Excitation in Highly Charged <sup>229</sup>Th Ions

    No full text
    The excitation of the 8 eV 229m^{229m}Th isomer through the electronic bridge mechanism in highly charged ions is investigated theoretically. By exploiting the rich level scheme of open 4f4f orbitals and the robustness of highly charged ions against photoionization, a pulsed high-intensity optical laser can be used to efficiently drive the nuclear transition by coupling it to the electronic shell. We show how to implement a promising electronic bridge scheme in an electron beam ion trap starting from a metastable electronic state. This setup would avoid the need for a tunable vacuum ultraviolet laser. Based on our theoretical predictions, determining the isomer energy with an uncertainty of 10510^{-5} eV could be achieved in one day of measurement time using realistic laser parameters

    Psychological sociomedical care in neonatology

    No full text
    Approximately 8.8 % of all newborn infants are born before 37 weeks of gestational age and are defined as preterm infants. For preterm infants the length of the initial stay in the neonatal intensive care unit (NICU) can last from weeks to months. Nowadays, medical treatment is focused on the neurological development which is affected not only by the physiological extrauterine environment but also by separation of mother and child during NICU treatment. Therefore, new care concepts encompass the optimal medical care of the infant as well as the best support for the whole family. The parents become the primary caregivers of their infant and are responsible for the development from the very beginning. Moreover, they need consultation, training and individualized discharge planning. Characteristics of structure and process of psychological sociomedical care for families of premature and ill, mature newborn children are described by a complex care model
    corecore