Asymptotically safe extensions of the Standard Model with flavour phenomenology

We investigate asymptotically safe extensions of the Standard Model with new matter fields arising in the TeV energy range. The new sector contains singlet scalars and vector-like fermions in representations which permit Yukawa interactions with the Standard Model leptons. Phenomenological implications are explored including charged lepton flavour violation, Drell-Yan processes and lepton anomalous magnetic moments. For the latter, we find that BSM contributions can be sizeable enough to explain the present experimental discrepancies of the electron and muon anomalous magnetic moments with the Standard Model.Comment: 4 pages, 4 figures. Contribution to the 2019 EW session of the 54th Rencontres de Morion

Quo vadis German Housing Policy?

The massive increase of real estate prices in some regions of Germany is a direct consequence of the ongoing financial and debt crisis. Low interest rates and high inflation expectations increase the demand for real estate. In addition to a potential price bubble risk, social problems arouse more and more public interest. Currently, many tenants are facing significant rent increases. Thus, the shortage of housing dominates current housing policy discussions. The so-called “package for affordable building and living” includes stricter rent controls and other economic policy interventions which aim to ease the situation in the real estate market, but the interventions have the opposite effect.Es handelt sich um eine englische Übersetzung des Originals.In den Koalitionsverhandlungen wurde ein „Paket für bezahlbares Bauen und Wohnen“ vereinbart. Das Paket enthält unter anderem eine Mietpreisbremse, deren Wirkung die Autoren insbesondere auf längere Sicht kritisch sehen. Sie fürchten, dass dadurch weniger Wohnungen angeboten werden und ein Schwarzmarkt den Preismechanismus, der Anbieter und Nachfrager zusammenbringt, ablöst. Alle Beteiligten müssten dann Nachteile erleiden

Quasi-Two-Level Flying-Capacitor-Converter for Medium Voltage Grid Applications

Medium voltage converters are becoming more relevant in future grid applications. Especially more wind and PV generation systems will be have to added and integrated into the grid in order to achieve the required reduction in CO2 emissions. High power generation units will be integrated into the grid at medium voltage level. Furthermore meshed MV grids will require interties based on MV converter technology. Today\u27s standard medium voltage converters are either based on the MMC technology or us 3L/5L approaches operated at low switching frequencies and containing bulky filters. Both concepts still lead to relatively high costs and low efficiencies which are major reasons for the slow spread of power converters in medium voltage grid applications.. Future grid applications demand less distortion, higher reliability and lower costs for converter systems at each voltage level. The Quasi-Two-Level operation of the flying capacitor multilevel converter with silicone-carbide (SiC) based semiconductors is a method for achieving these requirements for medium voltage converters. This paper presents a new concept for minimizing capacitance and balancing the capacitors with fast switching semiconductors. Moreover, a novel approach for limiting the overvoltage stress caused by the Quasi-Two-Level modulation of a flying capacitor converter is presented

Can County Commissions Emerge as Players in Western Natural Resources Policy Development?

Many county commissioners in the western United States preside over rural and/or public lands-dominated counties. Their formal role in the development of natural resources public policy is poorly defined, but rapidly evolving. As part-time elected officials, they state needs for training in both policy process skills and technically oriented subject matter. A survey investigation of their nonformal learning environment was conducted. They desire more consistent involvement in issues dialogue and higher-quality interactions with various policy influencers. Commissioners overwhelmingly prefer consultation with county government officials--with more regularity, confidence, and credibility than with any other agency, consultant, or institution

Fixed Points in Supersymmetric Extensions of the Standard Model

We search for weakly interacting fixed points in extensions of the minimally supersymmetric standard model (MSSM). Necessary conditions lead to three distinct classes of anomaly-free extensions involving either new quark singlets, new quark doublets, or a fourth generation. While interacting fixed points arise prolifically in asymptotically free theories, their existence is significantly constrained as soon as some of the non-abelian gauge sectors are infrared free. Performing a scan over $\sim 200$k different MSSM extensions using matter field multiplicities and the number of superpotential couplings as free parameters, we find mostly infrared conformal fixed points, and a small subset with ultraviolet ones. All settings predict low-scale supersymmetry-breaking and a violation of $R$-parity. Despite of residual interactions, the running of couplings out of asymptotically safe fixed points is logarithmic as in asymptotic freedom. Some fixed points can be matched to the Standard Model though the matching scale comes out too low. Prospects for higher matching scales and asymptotic safety beyond the MSSM are indicated.Comment: 26 pages, 9 figure

A Highly Integrated 25-Level Cascaded H-Bridge Active Filter for the Mitigation of High Order Current Harmonics

The increasing share of power electronics in the conversion and distribution of electrical energy represents a novel challenge for energy quality and supply stability. It is to be expected that high-frequency current harmonics will increase significantly with the number of grid-connected power converters. To reduce the associated disadvantages, this paper presents a 25-Level Cascaded H-Bridge Active Filter for mitigating converter-induced current harmonics in the kilohertz range.~Compared to conventional active filters, the proposed use of a voltage-source active filter does not require high control bandwidth, tuning to specific frequencies or measurement and tracking of high frequency currents.~The highly integrated design on printed circuit boards allows a high number of voltage levels and a high power density at small additional effort and costs. A 12 kVA-demonstrator is used to mitigate the switching frequency current harmonics of a grid-connected two-level converter, verifying the effectiveness of the active filter configuration

Monitoring the antibiotic darobactin modulating the β-barrel assembly factor BamA

The β-barrel assembly machinery (BAM) complex is an essential component of Escherichia coli that inserts and folds outer membrane proteins (OMPs). The natural antibiotic compound darobactin inhibits BamA, the central unit of BAM. Here, we employ dynamic single-molecule force spectroscopy (SMFS) to better understand the structure-function relationship of BamA and its inhibition by darobactin. The five N-terminal polypeptide transport (POTRA) domains show low mechanical, kinetic, and energetic stabilities. In contrast, the structural region linking the POTRA domains to the transmembrane β-barrel exposes the highest mechanical stiffness and lowest kinetic stability within BamA, thus indicating a mechano-functional role. Within the β-barrel, the four N-terminal β-hairpins H1-H4 expose the highest mechanical stabilities and stiffnesses, while the four C-terminal β-hairpins H5-H6 show lower stabilities and higher flexibilities. This asymmetry within the β-barrel suggests that substrates funneling into the lateral gate formed by β-hairpins H1 and H8 can force the flexible C-terminal β-hairpins to change conformations

Die Wirkung von kupferdotiertem 45S5-bioaktivem Glas auf mesenchymale Stammzellen mit Fokus auf die VEGF-Expression

Hintergrund und Ziele: Mittels Tissue-Engineering werden Konstrukte hergestellt, die dem menschlichen Gewebe nachempfunden sind. 45S5-BG ist ein solches keramisches Knochenersatzmaterial mit hoher Porosität (ca. 90%). Die Kultivierung von mesenchymalen Stammzellen (MSC) auf 45S5-BG führt zur Differenzierung der Zellen in Osteoblasten. Thema der vorliegenden Studie ist der Einfluss einer Kupferdotierung der 45S5-BG-Scaffolds (engl. Gerüst) auf die Viabilität und die vascular endothelial growth factor (VEGF)-Expression in MSC. Methoden: MSC wurden entweder indirekt (über das Nährmedium) oder durch direkte Aussaat auf die Scaffolds mit dem Kupfer (0,1wt% und 1wt%) in Kontakt gebracht. Die Morphologie, Proliferation und Viabilität der Zellen wurde mittels Lichtmikroskopie, Scanning Electron Microscopy (SEM), Fluorescein-Diacetat (FDA)/Propidium-Iodid (PI) Staining, Alamar-Blue (AB) und PicoGreen (PG) analysiert. Die VEGF-Expression sowie die Expression knochenspezifischer Gene wurde mit der Real-Time Polymerasekettenreaktion quantifiziert. Ergebnisse und Beobachtungen: Es wurden keine Beeinträchtigungen der MSC in Bezug auf Proliferation und Morphologie durch die Kupferdotierung der Scaffolds festgestellt. Sowohl bei einem indirekten als auch bei einem direkten Zell-Scaffold-Kontakt proliferierten die MSC unabhängig von einer Kupferdotierung. Es konnte in zweidimensionaler Zellkultur eine gesteigerte VEGF Sekretion der 1 wt % kupferdotierten 45S5-BG-Scaffolds beobachtet werden. Praktische Schlussfolgerung: Kupfer kann aufgrund seiner (in den verwendeten Konzentrationen) niedrigen Toxizität und seines, die VEGF-Expression von MSC fördernden, Effektes eine Alternative zum Einsatz von angioinduktiven Wachstumsfaktoren im Rahmen des Knochen Tissue Engineerings darstellen

What magic can perform: théâtralité et performativité dans Doctor Faustus de Christopher Marlowe

Dans un contexte dominé par l’iconoclasme de l’anglicanisme anglais et par la “ textualisation ” de la culture religieuse, Christopher Marlowe transforme sa pièce Doctor Faustus (1589), mise en scène dans les théâtres de la banlieue londonienne, en une réflexion sur les capacités performatives et “ incarnationnelles ” du théâtre. Cet article étudie comment l’inflexion métaphorique du langage théologique que les autorités ecclésiastiques avaient utilisé pour dénoncer les effets pervers de la représentation théâtrale permet au dramaturge anglais de formuler une conception de l’art littéraire comme création d’un monde et non plus comme imitation de la nature. Ainsi, Marlowe requalifie en termes théâtraux le concept de performativité : alors que, dans le théâtre du monde, la performativité de la prédestination divine vouait les croyants à une situation de détresse existentielle, la performativité artistique redonnait aux spectateurs la possibilité de créer leur propre monde, le monde du théâtre. C’est pourquoi le remaniement esthétique du lexique et de l’imaginaire théologique s’avère la réponse la plus profonde de Marlowe à la crise de “ l’absolutisme théologique ” : il fait du théâtre un espace de jeu où le traumatisme provoqué par cette crise pouvait être travaillé et éventuellement dépassée par sa resignification dramatique. C’est dire que, dans la version marlowienne du mythe faustien, l’autoaffirmation humaine se réalise surtout à travers le pouvoir cathartique de l’illusion théâtrale

Portals into Higgs Stability

We address the notorious metastability of the standard model (SM) and promote it to a model building task: What are the new ingredients required to stabilize the SM up to the Planck scale without encountering subplanckian Landau poles? Using the SM extended by vector-like fermions, we chart out the corresponding landscape of Higgs stability. We find that the gauge portal mechanism, triggered by new SM charge carriers, opens up sizeable room for stability in a minimally invasive manner. We also find models with Higgs criticality, and Yukawa portals opening up at stronger coupling. Several models allow for vector-like fermions in the TeV-range, which can be searched for at the LHC. For nontrivial flavor structure severe FCNC constraints arise which complement those from stability, and push lower fermion masses up to $\mathcal{O}(10^3\,\text{TeV})$.Comment: 18 pages, 16 figure