956 research outputs found

    Non-local anomaly of the axial-vector current for bound states

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    We demonstrate that the amplitude <ργν(qˉγνγ5q)0><\rho\gamma|\partial_\nu (\bar q\gamma_\nu \gamma_5 q)|0> does not vanish in the limit of zero quark masses. This represents a new kind of violation of the classical equation of motion for the axial current and should be interpreted as the axial anomaly for bound states. The anomaly emerges in spite of the fact that the one loop integrals are ultraviolet-finite as guaranteed by the presence of the bound-state wave function. As a result, the amplitude behaves like 1/p2\sim 1/p^2 in the limit of a large momentum pp of the current. This is to be compared with the amplitude which remains finite in the limit p2p^2\to\infty. The observed effect leads to the modification of the classical equation of motion of the axial-vector current in terms of the non-local operator and can be formulated as a non-local axial anomaly for bound states.Comment: revtex, 4 pages, numerical value for κ\kappa in Eq. (19) is corrected, Eqs. (22) and (23) are modified. New references added. Results remain unchange

    German and Italian Users of Web-Accessed Genetic Data: Attitudes on Personal Utility and Personal Sharing Preferences. Results of a Comparative Survey (n=192)

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    Genetic information is increasingly provided outside of the traditional clinical setting, allowing users to access it directly via specialized online platforms. This development is possibly resulting in changing ethical and social challenges for users of predictive genetic tests. Little is known about the attitudes and experiences of users of web-accessed genetic information. This survey analyzes data from two European countries with regard to the utility of genetic information, the users\u2019 ways of making use of and dealing with information, and their sharing behavior. Particular focus is given to ethical and social questions regarding the motivation to share personal genetic results with others. Social factors tested for are national background, gender, and marital, parental, and educational status. This study will contribute to public discourse and offer ethical recommendations. The study will also serve to validate the developed questionnaire for use in population representative surveys

    Laue photography of fine crystalline particles

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    Qualitätsprodukt Erziehungsberatung. Empfehlungen zu Leistungen, Qualitätsmerkmalen und Kennziffern

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    Neben einer Beschreibung der Leistung Erziehungs- und Familienberatung - Beratung und Therapie, präventive Angebote und Vernetzungsaktivitäten - werden ihre Qualitätsmerkmale - gegliedert nach Struktur-, Prozess- und Ergebnisqualität - ausführlich dargestellt und Kennziffern zu ihrer quantitativen Erfassung vorgeschlagen. Der Anhang enthält u.a. eine Kurzfassung der vorliegenden Empfehlungen zu Leistungen, Qualitätsmerkmalen und Kennziffern. (DIPF/Autor

    Immersed superhydrophobic surfaces: Gas exchange, slip and drag reduction properties

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    Superhydrophobic surfaces combine high aspect ratio micro- or nano-topography and hydrophobic surface chemistry to create super water-repellent surfaces. Most studies consider their effect on droplets, which ball-up and roll-off. However, their properties are not restricted to modification of the behaviour of droplets, but potentially influence any process occurring at the solid-liquid interface. Here, we highlight three recent developments focused on the theme of immersed superhydrophobic surfaces. The first illustrates the ability of a superhydrophobic surface to act as a gas exchange membrane, the second demonstrates a reduction in drag during flow through small tubes and the third considers a macroscopic experiment demonstrating an increase in the terminal velocity of settling spheres
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