Commissioning of large vacuum systems

This paper will give an overview of the various steps of the commissioning of large vacuum systems for accelerators. Following some introductory remarks, the pump-down, leak check, bake-out as well as component, interlock, and safety checks will be covered in detail. Special emphasis will be given to beam vacuum systems in combination with cryogenic systems. Finally, the transition from the commissioning phase to beam operation will be treated. Practical examples will illustrate most of the topics

Macroevolution of Bold Color Patterns Across Teleostean Fishes

Fishes include some of the most visually striking vertebrate radiations and have repeatedly evolved bold color patterns, including bars, stripes, and spots. Such strong color patterns are hypothesized to provide multiple functions, including avoiding predation by obscuring recognizable features and communicating with others to secure territories and mates. Despite increasing focus on the functions and proximate drivers of color pattern evolution, the relevance of such pressures across broad taxonomic and time scales remain much less resolved. Using over 5000 species within the largest vertebrate radiation, teleostean fishes, I employ phylogenetic comparative methods to explore the lability and potential coevolutionary relationships between color pattern traits and habitat. Evolutionary models reveal that pattern traits are labile across fishes and transitions most often occur between patternless and non-contrast pattern species. I also find support for the long-held belief that reef fishes are more patterned than their non reef-dwelling marine relatives. Given the marked diversity of body shapes within this group and proposed functional relationships between fish body depth and stripe orientation on the body, I also test for relationships between color pattern types and body shape. I find differences in body shapes between species with singular versus repeating patterns, such as single and multiple stripes, suggesting potential coevolution of color pattern and morphology over macroevolutionary scales. This study is a key step towards uncovering the story behind the persistence of bold color patterns in nature and provides insight into how evolutionary pressures shape color displays across deep time

Local quantum ergodic conjecture

The Quantum Ergodic Conjecture equates the Wigner function for a typical eigenstate of a classically chaotic Hamiltonian with a delta-function on the energy shell. This ensures the evaluation of classical ergodic expectations of simple observables, in agreement with Shnirelman's theorem, but this putative Wigner function violates several important requirements. Consequently, we transfer the conjecture to the Fourier transform of the Wigner function, that is, the chord function. We show that all the relevant consequences of the usual conjecture require only information contained within a small (Planck) volume around the origin of the phase space of chords: translations in ordinary phase space. Loci of complete orthogonality between a given eigenstate and its nearby translation are quite elusive for the Wigner function, but our local conjecture stipulates that their pattern should be universal for ergodic eigenstates of the same Hamiltonian lying within a classically narrow energy range. Our findings are supported by numerical evidence in a Hamiltonian exhibiting soft chaos. Heavily scarred eigenstates are remarkable counter-examples of the ergodic universal pattern.Comment: 4 figure

NATO defence planning between Wales and Warsaw: politico-military challenges of a credible assurance against Russia

The far-reaching measures agreed by NATO at the Alliance’s 2014 Summit in Wales substantially increase operational readiness but fall short in guaranteeing the security of all member states against Russia. The Alliance therefore faces difficult discussions before the next Summit in Warsaw in July 2016. Member states will have to improve capabilities and the operational readiness of their armed forces, which will come at a cost. Indefinitely avoiding the question of the role of nuclear weapons in defensive planning will not be possible. And finally, a credible assurance for the exposed Baltic States may not be feasible in the framework of the NATO-Russia Founding Act. As a transitory step, compromises can be reached, perhaps in the form of establishing an extensive infrastructure for a substantial pre-positioning of materiel. In the absence of a fundamental improvement of NATO’s relationship with Russia, however, further measures will likely become necessary. (Autorenreferat

Symmetry breaking: A tool to unveil the topology of chaotic scattering with three degrees of freedom

We shall use symmetry breaking as a tool to attack the problem of identifying the topology of chaotic scatteruing with more then two degrees of freedom. specifically we discuss the structure of the homoclinic/heteroclinic tangle and the connection between the chaotic invariant set, the scattering functions and the singularities in the cross section for a class of scattering systems with one open and two closed degrees of freedom.Comment: 13 pages and 8 figure

Ambitious framework nation: Germany in NATO: Bundeswehr capability planning and the "Framework Nations Concept"

Berlin is pursuing ambitious plans for security and defence, with significant potential for the Bundeswehr and European partner militaries. In the long-term, the Bundeswehr could well become Europe’s indispensable army, with Germany as a "framework nation" contributing decisively to NATO's readiness. This will require the future German government to accept an unaccustomed politico-military leadership role. It will also be necessary to increase defence spending for the long term. (author's abstract

Explaining the gender wage gap of graduates in STEM subjects. An analysis with the DZHW graduate panel 2001

Dieser Beitrag analysiert den gender wage gap bei AbsolventInnen der MINT-Studienfächer, welche bislang üblicherweise als homogene Gruppe bezüglich der Frauenanteile betrachtet wurden. Berücksichtigt werden die Einflüsse von geschlechtstypischer Sozialisation, Humankapitalfaktoren sowie Beschäftigungsmerkmalen auf die Einkommensdifferenz. Die Ergebnisse zeigen, dass allein die geschlechtsspezifische MINT-Fachwahl und das Humankapital 50% des gender wage gaps in den MINT-Fächern erklären. (DIPF/Orig.)This paper analyzes the gender wage gap between STEM fields in which the large heterogeneity in the share of women was neglected until now. The influence of gender-specific choice of field in STEM as well as Human Capital indicators and employment characteristics on income differences are being considered. The results show that especially the gender-specific choice of a STEM subject and the Human Capital indicators explain half of the gender wage gap in STEM fields. (DIPF/Orig.

mRNA-Expression von Genen des Fett- und Kohlenhydratstoffwechsels unterschiedlicher Fettlokalisationen bei Kühen

Problemstellung: Die Tiergesundheit hat sich bei Milchkühen in den letzten Jahren weltweit negativ entwickelt. Wichtigster Ausdruck dafür ist die auf ca. 2,4 Jahre verkürzte Nutzungsdauer. Dabei spielt das Fettmobilisationssyndrom eine dominante Rolle. Das Fettgewebe ist nicht nur als reiner Energiespeicher, sondern als endokrines stoffwechselaktives Organ anzusehen. Untersuchungen an Menschen und Mäusen haben gezeigt, dass das Fettgewebe in Abhängigkeit von seiner Lokalisation im Körper unterschiedlich auf metabolische und hormonelle Stimuli reagiert. Es gibt Hinweise, dass auch für das Rind ähnliche Differenzen angenommen werden können. Zielstellung: Um die Eigenschaften des bovinen Fettgewebes und seine Rolle im Energiestoffwechsel besser charakterisieren zu können, war das Ziel der vorliegenden Untersuchung, die mRNA-Expressionen ausgewählter für den Fettstoffwechsel relevante Gene im bovinen Fettgewebe an verschiedenen Lokalisationen grundlegend in gesunden Rindern zu untersuchen. Material und Methoden: Die Probenentnahme erfolgte an 12 gesunden Schlachtkühen direkt nach der Tötung, die aufgrund Schwermelkbarkeit oder Unfruchtbarkeit geschlachtet wurden. Das Fettgewebe wurde aus dem Omentum majus, dem Depotfett der Niere, im kaudalen Beckendrittel (retroperitoneales Fett), dem Hüftbereich (subkutanes Fett) und dem Fett an der Herzbasis entnommen. Die Proben wurden in Flüssigstickstoff tiefgefroren, auf Trockeneis transportiert und bis zur Untersuchung bei -70°C gelagert. Die mRNA-Expression für die verschiedenen Gene (Hormonsensitive Lipase (HSL), Lipoproteinlipase (LPL), Fettsäuresynthase (FASN), Leptin, Adiponektin, Retinolbindungsprotein 4 (RBP4), Tumornekrosefaktor (TNF) und Interleukin 6 (IL-6), Fettsäurebindungsproteine (FABP3, 4 und 5) und Glukosetransporter 4 (GLUT4)) , wurden mit einer quantitativen real time (RT)-PCR gemessen. Ergebnisse: Die mRNA-Expressionen der verschiedenen oben genannten Gene, ausgenommen IL-6 und FABP3, sind im bovinen Fettgewebe nachweisbar. Die mRNA-Expressionen unterschieden sich in den einzelnen Fettdepots nicht signifikant. Ausnahme hierbei bildete RBP4, dessen mRNA im pericardialen Fett signifikant höher exprimiert war als im subkutanen und omentalen Depot. Die mRNA-Expression des subkutanen, omentalen, perirenalen und pericardialen Fettdepots korrelierten signifikant positive untereinander. Schlussfolgerung: Die mRNA-Expressionen der in den Fettstoffwechsel involvierten und untersuchten Gene gesunder Rinder waren nachweisbar, unterschieden sich jedoch nicht signifikant von einander mit Ausnahme der RBP4 mRNA. Die positiven signifikanten Korrelationen zwischen dem subkutanen, omentalen, perirenalen und pericardialen Fettlokalisationen und gleichmäßigen Expressionen innerhalb der Gewebe deuten auf eine einheitliche Fettmetabolismus des gesamten Körpers. Verglichen mit Ergebnissen der Humanmedizin sind nur wenige Übereinstimmungen (HSL, LPL, GLUT4,TNF) zu eruieren. Weitere Studien mit gesunden Tieren im Vergleich zu erkrankten Rindern müssen klären, ob eine mögliche Verschiebung der mRNA-Konzentrationen auf das Fettmobilisationssyndrom hinweisen.Purpose: Over the last years, the situation of animal health concerning dairy cows has developed worldwide in an adverse way. Most important indicator is the shortened useful life of approx. 2.4 years. The fat mobilization syndrome plays a dominant role in this process. Apparently, fatty tissue does not only serve as a mere energy reservoir, but also as an endocrin organ with metabolic activity. Researches on humans and mice have shown fatty tissue to react on metabolic and hormonal stimuli in different ways, depending on its body localization. There are dues to anticipate, similar differences in cattle. Objectives: In order to better characterize the attributes of bovine fatty tissue and its purpose in metabolism, the present study aims examine basically the expression of mRNA in selected genes which are important for lipid metabolism in bovine fatty tissue of different localizations in healthy cattle. Methods and material: Samples where taken from twelve carcasses of healthy dairy cows slaughtered for reason of difficult milking or infertility directly after killing. Fatty tissue was taken from omentum major, kidney capsula, caudal pelvis area (retroperiteonal fat), hip area (subcutaneous fat), and cardiac base. It was instantly quick-freezed in liquid nitrogen, put on dry ice while transporting, and stored at -70°C until analysis. The expression of mRNA of different genes (hormone-sensitive lipase (HSL), lipoproteine lipase (LPL), fatty acid synthase (FASN), fatty acid binding proteine (FABP3,4 and 5), retinol binding proteine 4 (RBP4), adiponectine, glucose transporter 4 (GLUT4), leptin, interleukin-6 (IL-6), and tumor necrosis factor a (TNFα) was measured by means of a quantitative real-time (RT)-PCR. Results: The mRNA-expressions of all these different genes except IL-6 and FABP3 were detected in bovine fatty tissue. The differences of mRNA-expression between sample localization were not statistically significant. RBP4 was excepted, which mRNA showed a significantly higher expression in pericardial fat than in subcutaneous and omental fat, respectively. The correlation between mRNA-expressions of subcutaneous, omental, pericardial and perirenal fat was significant. Conclusions: The mRNA-expression of examined genes being involved in fatty tissue metabolism, were detected in healthy cattle, but were not significantly different, except RBP4. Significantly positive correlations between subcutaneous, omental, perirenal and pericardial localization and consistent expression indicate an integrative metabolism of the whole body. Compared to results of the human medicine only few analogies (HSL, LPL, GLUT4, TNF) were found. Further studies comparing healthy and diseased cattle will have to prove, if possible displacements of the mRNA-level can indicate the fat mobilization syndrome being present