Quantum states of neutrons in the gravitational field and limits for non-Newtonian interaction in the range between 1 micron and 10 microns

Quantum states in the Earth's gravitational field can be observed, when ultra-cold neutrons fall under gravity. In an experiment at the Institut Laue-Langevin in Grenoble, neutrons are reflected and trapped in a gravitational cavity above a horizontal mirror. The population of the ground state and the lowest states follows, step by step, the quantum mechanical prediction. An efficient neutron absorber removes the higher, unwanted states. The quantum states probe Newtonian gravity on the micrometer scale and we place limits for gravity-like forces in the range between 1 micron and 10 microns.Comment: Aspects of Quantum Gravity, ed. by C. Laemmerzahl, Springer, Berlin, Heidelberg 2003, (Lecture notes in physics

Struktur und Niveaus des Fachwissens von Kfz-Mechatronikern gegen Ende der formalen Ausbildung

ZusammenfassungIn diesem Beitrag stellen wir Ergebnisse zum Fachwissen von Kfz-Mechatronikern vor, das sich als in hohem Grade prädiktiv für berufsfachliche Leistungen in den zentralen Handlungsfeldern von Kfz-Mechatronikern erweist. Die Analysen gründen auf einer Stichprobe von rund 1000 Auszubildenden. Die in früheren Modellierungen dokumentierten Strukturen des Fachwissens können weitgehend repliziert werden, die in früheren Modellierungen beobachtbaren Inkonsistenzen zur Ausdifferenzierung des Fachwissens an fachsystematischen Inhaltsbereichen einerseits und tätigkeitsbezogenem Wissen andererseits können aufgelöst werden. Die in anderen Untersuchungen identifizierten Schwierigkeits-merkmale der berufsfachlichen Aufgaben können partiell repliziert werden, einen besonders hohen Erklärungsanteil erbringen Merkmale des Aufgabenformats. Als schwierig erwies es sich, diese Aufgabenmerkmale für die Modellierung von Fachwissensniveaus zu nutzen, was abschließend eingehend diskutiert wird.Schlüsselwörter: Kfz-Mechatroniker, Fachwissen, Strukturmodellierung, schwierigkeits-bestimmende Aufgabenmerkmale, NiveaumodellierungStructure and Levels of Car Mechatronics Technicians’ Professional Knowledge towards the End of Vocational TrainingAbstractThis paper examines the results of modeling professional knowledge of car mechatronics technicians. Professional knowledge is highly predictive for explaining professional competences in key areas in the work of car mechatronics technicians. The analyses are based on a sample of 1000 trainees. The structure of the professional knowledge found in previous studies could largely be replicated. Hereby we were able to resolve the inconsistencies between content specific dimensions and activity specific dimensions that existed in previous models. The difficulty features of the profession specific tasks that were identified in previous studies could partially be replicated. Features of the item format predict the item difficulty particularly well. It turned out to be very difficult to take those features as a basis for proficiency scaling which we finally discuss in detail.Keywords: car mechatronics technicians, professional knowledge, knowledge structure, difficulty features of items, proficiency scalin

Biological and Pharmacokinetic Studies with β-Peptides

Interactions and cleavage reactions of β-amino acids and β-oligopeptides (up to nine residues, carrying the side chains of Ala, Val, Leu, Ile, Phe, Ser, Lys, and Hop) with biological systems, such as the most potent peptidases (pronase, proteinase K, 20S proteasome), microorganisms (Pseudomonas aeruginosa and Pseudomonas putida), and mammalian blood (intravenous application to rats) have been investigated and compared with ?-peptides. The results are: i) the three peptidases do not cleave β-peptides at all (within 24 h), and they are not inhibited by a β-peptide; ii) except for certain 3-aminobutanoic-acid (β-HAla) derivatives, neither free, nor N-acetyl-β-amino acids, nor β-peptides (offered as sole N and C source) lead to growth of the two bacteria tested; iii) two water-soluble β-heptapeptides (with Lys side chains) were shown to have elimination half-lives t1/2(β) of 3 and 10 h at 100- and 30-ng/ml levels, respectively, in the rodent blood – much larger than those of α-peptides. Thus, the preliminary results described here confirm the much greater stability of β-peptides, as compared to α-peptides, towards metabolization processes, but they also suggest that there may be interactions (by hitherto unknown mechanisms) between the worlds of α- and β-peptides

Design of the Magnet System of the Neutron Decay Facility PERC

The PERC (Proton and Electron Radiation Channel) facility is currently under construction at the research reactor FRM II, Garching. It will serve as an intense and clean source of electrons and protons from neutron beta decay for precision studies. It aims to contribute to the determination of the Cabibbo-Kobayashi-Maskawa quark-mixing element $V_{ud}$ from neutron decay data and to search for new physics via new effective couplings. PERC's central component is a 12m long superconducting magnet system. It hosts an 8m long decay region in a uniform field. An additional high-field region selects the phase space of electrons and protons which can reach the detectors and largely improves systematic uncertainties. We discuss the design of the magnet system and the resulting properties of the magnetic field.Comment: Proceedings of the International Workshop on Particle Physics at Neutron Sources PPNS 2018, Grenoble, France, May 24-26, 201

Development of Agricultural Market and Trade Policies in the CEE Candidate Countries.

This synthesis report focuses on the evolution of agricultural market and trade policies in the Central and Eastern European (CEE) candidate countries in the period 1997 to 2001. The developments were crucially influenced by (OECD, 2000a): ⢠the situation in world agricultural markets; ⢠the overall macroeconomic development in the countries considered; ⢠the prospective EU accession; ⢠bringing domestic agricultural policy in line with the Uruguay Agreement on Agriculture (URAA). High 1997 agricultural prices on world commodity markets were followed by a marked depression in 1998. With the exemption of milk products this trend continued in 1999. Likewise the economic and financial crisis in Russia had a considerable impact on agricultural policies. It hit the regions´ exports resulting in a decline in industrial as well as agricultural output1. Thus, compared to the previous years most of the CEE candidate countries experienced a slow down or even negative rates of growth in their Gross Domestic Product (GDP) in 1998 and 1999. In addition those countries felt increased budgetary pressures. Agricultural market and trade policies largely reacted to these developments. Border protection was increased in many countries in 1998. This was combined in some cases with export subsidies, and ad hoc producer aids to mitigate the adverse effects. The prospect of EU accession also had an influence on the agricultural policy design in the region with many countries implementing EU-type policy instruments. Thus, the importance of per hectare and per head payments increased in the region, quota like measures were implemented in some countries and as part of this development Estonia introduced tariffs for agro-food imports. Finally, many countries also continued to adjust their policies to comply with their commitments agreed to in the World Trade Organisation (WTO). Despite these general tendencies there are also differences in the development of agricultural policies between the various CEE candidates. Chapter 2 therefore provides an overview of the changes of agricultural market and trade policies in each of the 10 accession countries. It addresses the policy issues market access (e.g. tariffs, special safeguard measures), export subsidies (value and quantities) and domestic support (intervention policies, direct payments, input subsidies, production quotas). Chapter 3 provides a brief assessment of recent policy developments in the region in the light of EU accession and WTO commitments. The development of prices and values, e.g. export subsidies, agricultural support expenditure, were presented in the background papers provided by the country experts in current prices in national currencies. In this synthesis report they are in addition converted in Euro. This firstly allows for a better comparison among the CEE candidate countries as well as between those countries and the EU. Some of the accession countries still suffer from high inflation and thus a strong depreciation of their currency. Thus secondly, the conversion to Euros allows the comparisons to be made in real terms.Industrial Organization, International Development, Productivity Analysis,

Establishing a persistent interoperability test-bed for European geospatial research

The development of standards for geospatial web services has been spearheaded by the Open Geospatial Consortium (OGC) - a group of over 370 private, public and academic organisations (OGC, 1999-2009). The OGC aims to facilitate interoperability between geospatial technologies through education, standards and other initiatives. The OGC Service Architecture, described in the international standard ISO 19119, offers an abstract specification for web services covering data dissemination, processing, portrayal, workflows and other areas. The development of specifications covering each of these categories of web services has led to a significant number of geospatial data and computational services available on the World Wide Web (the Web). A project1 to establish a persistent geospatial interoperability test-bed (PTB) was commissioned in 2007 by the Association of Geographic Information Laboratories in Europe (AGILE), Commission 5 (Networks) of the European Spatial Data Research (EuroSDR) organisation and the OGC

MONOPOL - A traveling-wave magnetic neutron spin resonator for tailoring polarized neutron beams

We report on first experimental tests of a neutron magnetic spin resonator at a very cold neutron beam port of the high flux reactor at the ILL Grenoble. When placed between two supermirror neutron polarizers and operated in a pulsed traveling-wave mode it allows to decouple its time- and wavelength-resolution and can therefore be used simultaneously as electronically tunable monochromator and fast beam chopper. As a first ‘real’ scientific application we intend its implementation in the PERC (p roton and e lectron r adiation c hannel) project related to high-precision experiments in neutron beta decay

Amniotic fluid deficiency and congenital abnormalities both influence fluctuating asymmetry in developing limbs of human deceased fetuses

Fluctuating asymmetry (FA), as an indirect measure of developmental instability (DI), has been intensively studied for associations with stress and fitness. Patterns, however, appear heterogeneous and the underlying causes remain largely unknown. One aspect that has received relatively little attention in the literature is the consequence of direct mechanical effects on asymmetries. The crucial prerequisite for FA to reflect DI is that environmental conditions on both sides should be identical. This condition may be violated during early human development if amniotic fluid volume is deficient, as the resulting mechanical pressures may increase asymmetries. Indeed, we showed that limb bones of deceased human fetuses exhibited increased asymmetry, when there was not sufficient amniotic fluid (and, thus, space) in the uterine cavity. As amniotic fluid deficiency is known to cause substantial asymmetries and abnormal limb development, these subtle asymmetries are probably at least in part caused by the mechanical pressures. On the other hand, deficiencies in amniotic fluid volume are known to be associated with other congenital abnormalities that may disturb DI. More specifically, urogenital abnormalities can directly affect/reduce amniotic fluid volume. We disentangled the direct mechanical effects on FA from the indirect effects of urogenital abnormalities, the latter presumably representing DI. We discovered that both factors contributed significantly to the increase in FA. However, the direct mechanical effect of uterine pressure, albeit statistically significant, appeared less important than the effects of urogenital abnormalities, with an effect size only two-third as large. We, thus, conclude that correcting for the relevant direct factors allowed for a representative test of the association between DI and stress, and confirmed that fetuses form a suitable model system to increase our understanding in patterns of FA and symmetry development.Research Fund of the University of Antwerp, mobility grant from the Research Foundation – Flanders (FWO)

Large-Scale Recombinant Production of the SARS-CoV-2 Proteome for High-Throughput and Structural Biology Applications

The highly infectious disease COVID-19 caused by the Betacoronavirus SARS-CoV-2 poses a severe threat to humanity and demands the redirection of scientific efforts and criteria to organized research projects. The international COVID19-NMR consortium seeks to provide such new approaches by gathering scientific expertise worldwide. In particular, making available viral proteins and RNAs will pave the way to understanding the SARS-CoV-2 molecular components in detail. The research in COVID19-NMR and the resources provided through the consortium are fully disclosed to accelerate access and exploitation. NMR investigations of the viral molecular components are designated to provide the essential basis for further work, including macromolecular interaction studies and high-throughput drug screening. Here, we present the extensive catalog of a holistic SARS-CoV-2 protein preparation approach based on the consortium’s collective efforts. We provide protocols for the large-scale production of more than 80% of all SARS-CoV-2 proteins or essential parts of them. Several of the proteins were produced in more than one laboratory, demonstrating the high interoperability between NMR groups worldwide. For the majority of proteins, we can produce isotope-labeled samples of HSQC-grade. Together with several NMR chemical shift assignments made publicly available on covid19-nmr.com, we here provide highly valuable resources for the production of SARS-CoV-2 proteins in isotope-labeled form