Undetected Electron Backscattering in PERKEO III

The beta asymmetry in neutron beta decay is used to determine the ratio of axial-vector coupling to vector coupling most precisely. In electron spectroscopy, backscattering of electrons from detectors can be a major source of systematic error. We present the determination of the correction for undetected backscattering for electron detection with the instrument PERKEO III. For the electron asymmetry, undetected backscattering leads to a fractional correction of $5\times 10^{-4}$, i.e. a change by 40% of the total systematic uncertainty.Comment: Proceedings of the International Workshop on Particle Physics at Neutron Sources PPNS 2018, Grenoble, France, May 24-26, 201

Financing public sector investment

Globally, there is a massive shortfall in infrastructure investment. This is the result of a combination of several factors: (i) the continued rise in the global population; (ii) the ongoing process of urbanisation; (iii) a shortage of public spending on infrastructures due to the legacy effects of the Great Recession and the need to consolidate public budgets; and (iv) new challenges such as climate change and the IT revolution that require additional investments. The infrastructure gap is felt in developed countries as much as in emerging market and developing countries. In Europe, public investment at the municipal level has been hit particularly hard. In spite of substantial interest from the private sector, shortages of funding continue to be a major (though not the only) bottleneck on the path towards higher investment volumes. Using the example of Berlin, this article looks at some trends in urban infrastructure policies and discusses alternative sources of financing

Strukturelle und kriteriale Validität der literarästhetischen Urteilskompetenz. Projekt literarästhetische Urteilskompetenz

Die kompetenztheoretische Modellierung und empirische Validierung literarästhetischer Lehr-Lern-Prozesse gehört zu den schwierigsten und dringlichsten Aufgaben sprachbezogener Bildungsforschung. Die Schwierigkeit erklärt sich aus der besonderen Beschaffenheit des zu erfassenden Gegenstandes. Denn künstlerische Texte sind prinzipiell durch Polyvalenz bzw. Mehrdeutigkeit gekennzeichnet. … Die Dringlichkeit ergibt sich zum einen daraus, dass es einer theoretisch anschlussfähigen und empirisch tragfähigen Modellierung literarästhetischer Kompetenz bedarf, um Bildungsstandards, Lernstandserhebungen und die kompetenzorientierte Erforschung von Lehr-Lernprozessen im Hinblick auf literarästhetisches Verstehen auf ein wissenschaftlich solides Fundament zu stellen. … In diesem Beitrag wurde der Frage nachgegangen, ob sich ein dreidimensionales Modell der literarästhetischen Urteilskompetenz (LUK), für das literaturtheoretisch gute Grunde sprechen, empirisch bestätigen lasst oder ob sich ein theoretisch ebenfalls plausibles zweidimensionales LUK-Modell angesichts der ermittelten Daten als Überlegen erweist. Weiterhin wurde der Versuch unternommen, LUK gegen allgemeine Lesekompetenz abzugrenzen. (DIPF/Orig.

Enhancement of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) accumulation in Arxula adeninivorans by stabilization of production

Background: In recent years the production of biobased biodegradable plastics has been of interest of researchers partly due to the accumulation of non-biodegradable plastics in the environment and to the opportunity for new applications. Commonly investigated are the polyhydroxyalkanoates (PHAs) poly(hydroxybutyrate) and poly(hydroxybutyrate-co-hydroxyvalerate) (PHB-V). The latter has the advantage of being tougher and less brittle. The production of these polymers in bacteria is well established but production in yeast may have some advantages, e.g. the ability to use a broad spectrum of industrial by-products as a carbon sources. Results: In this study we increased the synthesis of PHB-V in the non-conventional yeast Arxula adeninivorans by stabilization of polymer accumulation via genetic modification and optimization of culture conditions. An A. adeninivorans strain with overexpressed PHA pathway genes for β-ketothiolase, acetoacetyl-CoA reductase, PHAs synthase and the phasin gene was able to accumulate an unexpectedly high level of polymer. It was found that an optimized strain cultivated in a shaking incubator is able to produce up to 52.1% of the DCW of PHB-V (10.8gL-1) with 12.3%mol of PHV fraction. Although further optimization of cultivation conditions in a fed-batch bioreactor led to lower polymer content (15.3% of the DCW of PHB-V), the PHV fraction and total polymer level increased to 23.1%mol and 11.6gL-1 respectively. Additionally, analysis of the product revealed that the polymer has a very low average molecular mass and unexpected melting and glass transition temperatures. Conclusions: This study indicates a potential of use for the non-conventional yeast, A. adeninivorans, as an efficient producer of polyhydroxyalkanoates

Limit on the Fierz Interference Term b from a Measurement of the Beta Asymmetry in Neutron Decay

In the standard model of particle physics, the weak interaction is described by vector and axial-vector couplings only. Non-zero scalar or tensor interactions would imply an additional contribution to the differential decay rate of the neutron, the Fierz interference term. We derive a limit on this hypothetical term from a measurement using spin polarized neutrons. This method is statistically less sensitive than the determination from the spectral shape but features much cleaner systematics. We obtain a limit of b = 0.017(21) at 68.27 C.L., improving the previous best limit from neutron decay by a factor of four.Comment: Phys. Rev. Lett., https://journals.aps.org/prl

Validity and responsiveness of the EQ-5D in assessing and valuing health status in patients with anxiety disorders

<p>Abstract</p> <p>Background</p> <p>The EQ-5D is a generic questionnaire which generates a health profile as well as index scores for health-related quality of life that may be used in cost-utility analysis.</p> <p>Aims of the study</p> <p>To examine validity and responsiveness of the EQ-5D in patients with anxiety disorders.</p> <p>Methods</p> <p>389 patients with anxiety disorders completed the EQ-5D at baseline and 6-month follow-up. Subjective measures of quality of life (WHOQOL-BREF) and psychopathology (BAI, BDI-II, BSQ, ACQ, MI) were used for comparison. Validity was analyzed by assessing associations between EQ-5D scores and related other scores. Responsiveness was analyzed by calculating effect sizes of differences in scores between baseline and follow-up for 3 groups indicating more, constant or less anxiety. Meaningful difference scores for shifting to less or more anxiety were derived by means of regression analysis.</p> <p>Results</p> <p>88.4% of respondents reported problems in at least one of the EQ-5D dimension at baseline; the mean EQ VAS score was 63.8. The EQ-5D dimension most consistently associated with the measures used for comparison was 'anxiety/depression'. EQ VAS and EQ-5D index scores were highly correlated (|r|>0.5) with scores of the WHOQOL-BREF dimensions 'physical', 'mental' and 'overall' as well as BAI and BDI-II. The EQ-5D index tended to be the most responsive score. Standardized meaningful difference scores were not significantly different between EQ VAS, EQ-5D index and measures used for comparison.</p> <p>Conclusions</p> <p>The EQ-5D seems to be reasonably valid and moderately responsive in patients with anxiety disorders. The EQ-5D index may be suitable for calculating QALYs in economic evaluation of health care interventions for patients with anxiety disorders.</p> <p>Trial registration</p> <p>Current Controlled Trials ISRCTN15716049</p