Resolving the Tevatron Top Quark Forward-Backward Asymmetry Puzzle: Fully Differential Next-to-Next-to-Leading-Order Calculation

We determine the dominant missing Standard Model (SM) contribution to the top quark pair forward-backward asymmetry at the Tevatron. Contrary to past expectations, we find a large, around 27%, shift relative to the well-known value of the inclusive asymmetry in next-to-leading order (NLO) QCD. Combining all known Standard Model corrections, we find that AFB^{SM} = 0.095 +- 0.007. This value is in agreement with the latest D0 measurement [V. M. Abazov et al. (D0 Collaboration), Phys. Rev. D 90, 072011 (2014)] AFB^{D0} = 0.106+- 0.03 and about 1.5 sigma below that of CDF [T. Aaltonen et al. (CDF Collaboration), Phys. Rev. D 87, 092002 (2013)] AFB^{CDF} =0.164 +- 0.047. Our result is derived from a fully differential calculation of the next-to-next-to leading order (NNLO) QCD corrections to inclusive top pair production at hadron colliders and includes - without any approximation - all partonic channels contributing to this process. This is the first complete fully differential calculation in NNLO QCD of a two-to-two scattering process with all coloured partons.Comment: 6 pages, 4 figures. Published journal version: title extended and few clarifications adde

Further exploration of top pair hadroproduction at NNLO

Top quark pair production is one of the cornerstones of the physics program at hadron colliders. In this contribution, we further explore the phenomenological implications of the recent NNLO calculation of the total inclusive cross-section. We provide a comparison of the scale dependence of the top pair hadroproduction cross section at different perturbative orders and study its perturbative convergence (with and without soft-gluon resummation). We also sketch how the NNLO top quark cross-section could be used to improve searches of physics beyond the Standard Model.Comment: 8 pages, 8 figures. Contribution to the proceedings of the twenty-seventh workshop "Les Rencontres de Physique de la Vall\'ee d'Aoste", held 24 Feb.-02 Mar. 2013 in La Thuile, Aosta Valley, Ital

Contacts between wild birds and domestic poultry - a serious factor in transmission of avian influenza?

Wasservögel gelten als Hauptreservoir für viele Subtypen niedrig pathogener Influenza A Viren. Auch auf eine mögliche Verbreitung hoch pathogener Formen durch Wasservögel gibt es Hinweise. Daher wird die Übertragung von Geflügelpest-Erregern von Wildvögeln auf Hausgeflügel und umgekehrt bei Kontakten zwischen beiden Gruppen (z.B. in Freilandhaltungen) als Risikofaktor für die Ausbreitung der Seuche angesehen und Aufstallungsgebote zählen zum Standardrepertoire der Reaktion auf eine mögliche Geflügelpest-Gefahr. Daten zum tatsächlichen Ausmaß solcher Wildvogel-Geflügel-Kontakte waren jedoch bislang nur in Form einzelner Anekdoten verfügbar. Im Rahmen des Projektes „Constanze“ zur Untersuchung des Geflügelpest-Risikos am Beispiel des Bodenseeraumes wurden von Oktober 2007 bis einschließlich Januar 2008 im Rahmen einer Diplomarbeit schweizerische Geflügel-Freilandhaltungen auf Kontakte von Wildvögeln mit Hausgeflügel untersucht. Ziel dabei war, das Ausmaß dieser Kontakte hinsichtlich eines möglichen Übertragungsrisikos von Geflügelpest-Erregern abzuschätzen. Die Beobachtungen wurden an 21 Geflügelhaltungen mit Freilauf in den Kantonen Thurgau und Sankt Gallen durchgeführt. Während der Gesamtbeobachtungszeit von 65 Stunden wurde abgesehen von Besuchen von einmal drei und einmal einer Lachmöwe kein Fall eines Auftretens von Wasservögeln in den Geflügelhaltungen festgestellt. Es gab lediglich Kontakte zu Landvögeln urbaner Lebensräume wie Haussperling, Buchfink oder Rabenkrähe und indirekte Kontakte zu bzw. Anwesenheit von Greifvögeln, Lachmöwen, Tauben und einigen weiteren Arten in der näheren Umgebung. Die beobachteten Vogelarten sind nach derzeitigem Kenntnisstand nicht an der Übertragung der Vogelgrippe beteiligt. Obwohl die Beobachtungen im Winter zu einer Zeit stattfanden, als mehrere zehntausend Entenvögel am Bodensee anwesend waren, wurde kein einziger Kontakt mit dieser für das Vogelgrippegeschehen relevanten Gruppe beobachtet. Insgesamt kann geschlossen werden, dass das Risiko einer Übertragung der Geflügelpest von einem Wildvogel auf Hausgeflügel oder umgekehrt durch die direkten Kontakte aufgrund von deren Seltenheit im Bodenseeraum eher vernachlässigbar ist.Waterbirds are seen to be the main reservoir for many subtypes of low pathogenic avian influenza A virus. There is also evidence for a potential spread of high pathogenic subtypes through waterbirds. Transmission of avian influenza virus from wild birds into poultry and vice versa therefore is seen as a risk factor for the spread of the disease and a prohibition of keeping poultry outdoors is among the standard repertoire in veterinary disease defense. Data about the extent of contacts between wild birds and poultry until now are only available through single anecdotes. Within the framework of project „Constanze“ (exploration of the bird flu risk at the example of Lake Constance) between October 2007 and January 2008 Swiss poultry farms with open air enclosures were searched for contacts between poultry and wild birds. It was aimed to estimate the extent of these contacts in the light of a potential transmission risk of influenza virus. Observations were made on 21 poultry holdings with open air enclosures in the districts of Thurgau and St. Gallen. During 65 hrs. of observation no visit of a waterbird was registered, except for registration of three and one Black headed Gulls. Only contacts with land birds of typical species of urban areas like House Sparrow, Chaffinch or Carrion Crow were registered. In addition, birds of prey, Black-headed Gulls and pigeons have been observed in the vicinity of the enclosures. According to current knowledge the bird species observed are not involved in the transmission of avian influenza. Despite several tens of thousands of anatids being present in the Lake Constance area at time of the study not a single contact between this relevant group for avian influenza and poultry has been seen. We conclude that - due to it’s infrequency - the transmission risk of avian influenza between wild birds and poultry through direct contacts in the Lake Constance area is of minor relevance

Comparison of Self-Reported and Device-Based Measured Physical Activity Using Measures of Stability, Reliability, and Validity in Adults and Children

Quantification of physical activity (PA) depends on the type of measurement and analysis method making it difficult to compare adherence to PA guidelines. Therefore, test-retest reliability, validity, and stability for self-reported (i.e., questionnaire and diary) and device-based measured (i.e., accelerometry with 10/60 s epochs) PA was compared in 32 adults and 32 children from the SMARTFAMILY study to examine if differences in these measurement tools are systematic. PA was collected during two separate measurement weeks and the relationship for each quality criteria was analyzed using Spearman correlation. Results showed the highest PA values for questionnaires followed by 10-s and 60-s epochs measured by accelerometers. Levels of PA were lowest when measured by diary. Only accelerometry demonstrated reliable, valid, and stable results for the two measurement weeks, the questionnaire yielded mixed results and the diary showed only a few significant correlations. Overall, higher correlations for the quality criteria were found for moderate than for vigorous PA and the results differed between children and adults. Since the differences were not found to be systematic, the choice of measurement tools should be carefully considered by anyone working with PA outcomes, especially if vigorous PA is the parameter of interest

Foundations for the Integration of Enterprise Wikis and Specialized Tools for Enterprise Architecture Management

Organizations are challenged with rapidly changing business requirements and an ever-increasing volume respectively variety of information. Enterprise Architecture (EA) and its respective management function are considered as means to overcome these challenges. Appropriate tool support to this end is an elementary success factor to guide the EA management (EAM) initiative. Nevertheless, practitioners perceive currently available tools specialized for EAM as not sufficient in their organizations. Major reasons are inflexible data models as well as missing integration with processes and their focus on expert users. Regarding these limitations Enterprise Wikis provide practice proven solutions already exploited by organizations. These Enterprise Wikis are able to extend the capabilities of existing EA tools to cope with unstructured information and leverage a better utilization of structured EA information. In this paper we present the foundations for an integration of specialized EAM tools and Enterprise Wikis. We elaborate scenarios for both tool species using a practitioner survey and differentiate four integration cases

Automatisierte Generierung von Simulationsmodellen unter Verwendung des Core Manufacturing Simulation Data (CMSD) Information Model - Implementierung eines Pilotszenarios

Aufgrund verkürzter Produktlebenszyklen und gleichzeitig gestiegener Planungskomplexität besteht für Unternehmen des produzierenden Gewerbes die Notwendigkeit, die Planungsprozesse zur Erstellung und dem Betrieb der Produktionseinrichtungen zu verbessern. Eine Möglichkeit zur Verwirklichung der Ziele nach steigender Planungsqualität und –sicherheit und dabei verringerten Planungsdauer und –aufwand, ist der Einsatz planungs- bzw. betriebsbegleitender Ablaufsimulationen. Voraussetzung hierfür ist die Integration der Simulation in das Umfeld der betrieblichen Anwendungssysteme der Planung und Fertigungssteuerung sowie die Reduzierung des Aufwandes zur Erstellung der Simulationsmodelle, was u. a. durch eine automatisierte Generierung erreicht werden soll. Die Anbindung der Simulationssysteme durch leistungsstarke und flexible Schnittstellen ist heutzutage noch nicht zufriedenstellend gelöst und behindert somit den konsequenten Einsatz der Simulationstechnik. Um dem Problem der unzureichenden Schnittstellenanbindungen entgegenzutreten, entstand in mehrjähriger Arbeit das „Core Manufacturing Simulation Data“ (CMSD) Information Model. Dieses definiert eine Spezifikation für Kerndaten von Fertigungssimulationen. Mithilfe der im CMSD Information Model enthaltenen Datenstrukturen können Modellbeschreibungen für simulationsrelevante Daten formuliert und für den Datenaustausch genutzt werden. Als Datenaustauschformat findet das XML-Format Verwendung. Im Rahmen dieser Arbeit wird das CMSD Information Model auf die Nutzbarkeit zur Abbildung simulationsrelevanter Eingangsdaten für Ablaufsimulationen im fertigungstechnischen Umfeld hin untersucht. Dies geschieht anhand einer prototypischen Umsetzung eines automatisierten Simulationsmodellgenerators und eines konkreten, fiktiven Anwendungsbeispiels einer Werkstattfertigung. Die für das Beispiel benötigten Eingangsdaten werden mithilfe der Datenstrukturen des CMSD Information Model abgebildet und mittels Datenimport dem Modellgenerator zur Verfügung gestellt. Anschließend erfolgt ein automatisierter Modellaufbau. Darüber hinaus werden Anregungen zu Erweiterungen der prototypischen Umsetzung gegeben, um eine umfassende Anwendungslösung zu erreichen, welche zur Untersuchung des betriebsbegleitenden Einsatzes geeignet ist.Zugl.: Ilmenau, Techn. Univ., Diplomarbeit, 201

Key facets to build up eHealth and mHealth interventions to enhance physical activity, sedentary behavior and nutrition in healthy subjects – an umbrella review

Background Electronic (eHealth) and mobile (mHealth) health interventions can provide a large coverage, and are promising tools to change health behavior (i.e. physical activity, sedentary behavior and healthy eating). However, the determinants of intervention effectiveness in primary prevention has not been explored yet. Therefore, the objectives of this umbrella review were to evaluate intervention effectiveness, to explore the impact of pre-defined determinants of effectiveness (i.e. theoretical foundations, behavior change techniques, social contexts or just-in-time adaptive interventions), and to provide recommendations for future research and practice in the field of primary prevention delivered via e/mHealth technology. Methods PubMed, Scopus, Web of Science and the Cochrane Library were searched for systematic reviews and meta-analyses (reviews) published between January 1990 and May 2020. Reviews reporting on e/mHealth behavior change interventions in physical activity, sedentary behavior and/or healthy eating for healthy subjects (i.e. subjects without physical or physiological morbidities which would influence the realization of behaviors targeted by the respective interventions) were included if they also investigated respective theoretical foundations, behavior change techniques, social contexts or just-in-time adaptive interventions. Included studies were ranked concerning their methodological quality and qualitatively synthesized. Results The systematic search revealed 11 systematic reviews and meta-analyses of moderate quality. The majority of original research studies within the reviews found e/mHealth interventions to be effective, but the results showed a high heterogeneity concerning assessment methods and outcomes, making them difficult to compare. Whereas theoretical foundation and behavior change techniques were suggested to be potential positive determinants of effective interventions, the impact of social context remains unclear. None of the reviews included just-in-time adaptive interventions. Conclusion Findings of this umbrella review support the use of e/mHealth to enhance physical activity and healthy eating and reduce sedentary behavior. The general lack of precise reporting and comparison of confounding variables in reviews and original research studies as well as the limited number of reviews for each health behavior constrains the generalization and interpretation of results. Further research is needed on study-level to investigate effects of versatile determinants of e/mHealth efficiency, using a theoretical foundation and additionally explore the impact of social contexts and more sophisticated approaches like just-in-time adaptive interventions. Trial registration The protocol for this umbrella review was a priori registered with PROSPERO: CRD42020147902

The Tridirectional Relationship among Physical Activity, Stress, and Academic Performance in University Students: A Systematic Review and Meta-Analysis

Higher education students often suffer from physiological and psychological health problems caused by stress, which may negatively impact their academic performance (AP). Physical activity (PA) can be a promising strategy to buffer these stress-induced complaints. Therefore, the aim of this investigation was to summarize evidence for the tridimensional construct of PA, stress, and AP, as well as to quantify the relationships among these variables. Five databases (PubMed, Scopus, SMEI, ERIC, and Web of Science) were systematically searched in November 2019 for publications that examined PA, stress, and AP of university students, without any restrictions regarding the publication period. The systematic review includes four original research studies with a moderate-to-high risk of bias. Results of included studies were narratively summarized and quantified in a meta-analysis using random effect models. Whereas study results point to a positive relation between PA and AP, relationships between PA and stress seem to be negative, while the relation between stress and AP is undecided. The meta-analysis found no significant associations and considerable heterogeneity of the results. Findings indicate a research gap concerning the connection of PA, stress, and AP in university students. Future studies should use validated measuring tools and consider the timepoint of data collection in order to extract truly stressful periods