Graphene under bichromatic driving: Commensurability and spatio-temporal symmetries

We study the non-linear current response of a Dirac model that is coupled to two time-periodic electro-magnetic fields with different frequencies. We distinguish between incommensurable and commensurable frequencies, the latter characterized by their ratio p/q with co-prime integers p and q. Coupling the (effective) two-level system to a dissipative bath ensures a well-defined long-time solution for the reduced density operator and, thus, the current. We then analyze the spatio-temporal symmetries that force certain current components to vanish and close with conclusions for directed average currents.Comment: 8 pages, 5 figure

Entwicklung keramischer Vergussmassen mit Alkoxysilanen zur Steigerung der Haftfestigkeit

Die Haftung der Vergussmasse ist ein entscheidender Faktor für die Robustheit und Funktionalität eines leistungselektronischen Moduls. In dieser Arbeit wurde die Haftung von keramischen Vergussmassen weiterentwickelt. Es wurde ein Primer entwickelt, der auch bei hohen Temperaturen für kurze Zeiten gute Scherwerte liefert. Außerdem wurde eine gänzlich neue Vergussmasse entwickelt auf Basis von Alkoxysilanen. Besonders MTES zeigte vorteilhafte Eigenschaften für die Haftung unter Temperatur

Nuclear heating plants - an option for district heating in future?

For different reasons the substitution of fossil fuels in the energy system of the Federal Republik of Germany, which has a large market share in the heat market is an objective. Besides of the heat extraction from nuclear power plants the development of combined heat and power generation plants in high-temperature reactors and the heat production in heating reactors offer new perspectives for the use of nuclear energy for heat production. This paper presents the stage of development, the potential for application and the economic background of nuclear heating plants. These heating reactors are mainly designed to feed into typical district heating networks of the public utilities which are operated at temperatures of up to 120 to 130° C

Sol–gel encapsulation for power electronics utilizing 3-Glycidyloxypropyltriethoxysilane and 3-Mercaptopropyltrimethoxysilane

3-Glycidyloxypropyltriethoxysilane and 3-Mercaptosilane were used to prepare a composite together with aluminum oxide. The compound is a potential candidate for being used as inorganic encapsulation. FTIR results paired with head-space analysis revealed a hardening of the composite at above 130 °C and degradation of the sol–gel-network above 150 °C. The adhesion of these compounds was tested via shear tests. It showed, that the addition of 3-Mercaptopropyltriethoxysilane enhanced the adhesion on silver significantly. This is attributed to the covalent nature of the Ag-S bond, which is forming as compared to the solely dispersive forces, when 3-Mercaptopropyltriethxysilane is not used. By conducting the shear test under temperature activation energies for the breakages were calculated. These coincide well with the binding energy of Ag-S in case silver surfaces are examined. In the case of a copper surface, a mixture of covalent and dipole–dipole interactions are found, since the activation energy for breakage is smaller as the Cu-O bond energy

Bortezomib in antibody-mediated autoimmune diseases (TAVAB): study protocol for a unicentric, non-randomised, non-placebo controlled trial

Introduction: The clinical characteristics of autoantibodymediated autoimmune diseases are diverse. Yet, medical treatment and the associated complications are similar, that is, the occurrence of long-term side effects and the problem that a significant proportion of patients are non-responders. Therefore, new therapeutic options are needed. Bortezomib, a proteasome inhibitor, is effective in the treatment of multiple myeloma and data from experimental models and case reports suggest an effect in the treatment of autoantibody-mediated autoimmunity. In our study, we will determine the effect of bortezomib treatment on a shared surrogate parameter for clinical efficacy, namely change in autoantibody levels, which we chose as primary parameter. Methods and analysis: We designed a phase IIa trial with altogether n=18 treatment-refractory patients suffering from myasthenia gravis, systemic lupus erythematosus and rheumatoid arthritis that will be treated with bortezomib add-on to pre-existing therapy. Primary endpoint is the change in autoantibody levels 6 months after therapy. Secondary endpoints include concomitant medication, disease-specific clinical scores and measures of quality of life and activities of daily living. Ethics and dissemination: Safety parameters include neurophysiological and clinical signs of peripheral neuropathy as well as potential central nervous system side effects determined by olfactory and neuropsychological testing. The study has been approved by the local ethical committee and first participants have already been enrolled. This proof of concept study will contribute to improve our understanding of plasma cellspecific treatment approaches by assessing its safety and efficacy in reducing serum levels of antibodies known to mediate autoimmune disorders. We plan to publish the final results of our study in a peer reviewed journal and to present our findings at international conferences. Trial registration number: NCT02102594

Analysis of the N=4 Hubbard ring using a counting operator

We prove three theorems about the use of a counting operator to study the spectrum of model Hamiltonians. We analytically calculate the eigenvalues of the Hubbard ring with four lattice positions and apply our theorems to describe the observed level crossings.Comment: reference added tot the work of Schumann, small corrections mad

Kernenergie eine Lösung für das CO2-Problem?

Es werden hier Ergebnisse vorgestellt, die im Rahmen von Untersuchungen für die Enquete-Kommission "Vorsorge zum Schutz der Erdatmosphäre" des Deutschen Bundestages erarbeitet wurden. Neben der CO2-Minderung durch den verstärkten Einsatz der Kernenergie zur Energieerzeugung, der hier behandelt wird, gibt es weitere Möglichkeiten zur CO2-Einsparung, z. B. durch Energieeinsparung oder rationelle Energieanwendungen oder durch Substitution fossiler Energieträger untereinander. Weiter lassen sich CO2-Emissionen durch die Verwendung erneuerbarer Energieträger vermeiden, und schließlich läßt sich Kohlendioxid gegebenenfalls auch klimaunschädlich entsorgen. Hier werden die Möglichkeiten zur CO2-Minderung durch eine verstärkte Nutzung der Kernenergie zur Erzeugung von Strom und Niedertemperaturwärme untersucht. Nicht dargestellt werden die Möglichkeiten zur CO2-Minderung durch einen verstärkten Einsatz der Kernenergie zur Prozeßwärme- bzw. Wasserstofferzeugung

What about the partner? -factors associated with patient-perceived partner dyspareunia in men with Peyronie\u27s disease

Background: Limited data are available on how partners of men with Peyronie\u27s disease (PD) are affected by the disease. We sought to characterize PD patients whose curvatures result in pain for their partners during penetrative intercourse. Methods: We queried a database of all men undergoing initial evaluation for PD at a single clinic between March 2014 and June 2016. Patients were administered a questionnaire regarding sexual health concerns with domains including erectile dysfunction, ejaculatory dysfunction, libido, and penile curvature. In the penile curvature section, patients were specifically asked: Does the curvature cause your partner any pain during penetrative intercourse? (Y/N). Patients\u27 partners were not directly evaluated for conditions associated with dyspareunia. Additionally, patients interested in treatment for PD underwent objective curve assessment after intracavernosal injection of erectogenic medications along with penile duplex Doppler ultrasound. Statistical analysis was performed to identify differences in clinicopathologic variables and patient-responses to questionnaire prompts between patients who did and did not report partner pain with intercourse. Results: A total of 322 patients with information available on partner pain were included in the study. Patients who reported partner pain had significantly higher subjective erectile rigidity (mean 5.9/10 Conclusions: Men with superior erectile function, higher degrees of penile curvature and ventral curvatures were more likely to report partner pain during penetrative intercourse. These specific disease characteristics reported in this series may assist clinicians in identifying men who are more motivated to select more invasive therapies

Peptide Immunization Indicates that CD8+ T Cells are the Dominant Effector Cells in Trinitrophenyl-Specific Contact Hypersensitivity

The identity of the effector T cell population involved in contact hypersensitivity is still questionable with evidence promoting both CD4+ or CD8+ T cells. Previous experimental studies have relied on the in vivo depletion of T cell subsets using antibody, or the use of knock-out mice with deficiencies in either CD4+ or CD8+ T cell-mediated immunity. To address the role of the class I- and class II-mediated pathways of T cell activation in contact hypersensitivity responses in mice with an intact immune system, we utilized various trinitrophenyl-derivatized peptides, which bind specifically with H-2Kb (major histocompatibility complex class I) or H-2I-Ab (major histocompatibility complex class II). The subcutaneous injection of major histocompatibility complex class II-specific, but not of class I-binding, hapten-derivatized peptides in incomplete Freund's adjuvant induced specific, albeit low, contact hypersensitivity responsiveness to trinitrochlorobenzene. When bone-marrow-derived dendritic cells, however, were pulsed with the same peptides and administered intradermally, the opposite result was observed, namely that the class I binding peptides induced contact hypersensitivity responses similar to that observed after epicutaneous trinitrochlorobenzene application. In contrast, dendritic cells pulsed with major histocompatibility complex class II binding peptides did not reproducibly sensitize for contact hypersensitivity responses. Surprisingly, both immunization protocols efficiently induced CD8+ effector T cells. These results support the notion that CD8+ T cells are the dominant effector population mediating contact hypersensitivity responsiveness and that the CD4+ T cell subset only contributes little if at all

Abschätzung der technischen und wirtschaftlichen Potentiale des Beitrags zur Energieversorgung und zur Minderung klimarelevanter Spurengase durch Kernenergie in der Bundesrepublik Deutschland : Studie A.4.2.a und A.4.2.b

In diesem Arbeitspaket A.4.2 werden die Möglichkeiten der Minderung von CO2-Emissionen durch den Einsatz der Kernenergie untersucht. Dabei werden sechs Einsatzbereiche betrachtet, in denen die Kernenergie eine CO2-Emissionsminderung durch Substitution fossiler Energieerzeugung bewirken kann. In Kapitel 2 werden mögliche CO2-Emissionsminderungen im Bereich der Stromerzeugung, in Kapitel 3 bei der Fern- bzw. Nahwärmeerzeugung diskutiert. In den Kapiteln 4 bis 7 werden die CO2-Minderungspotentiale durch die Nutzung der Kernenergie zur Veredelung fossiler Energieträger, zur Prozeßdampf- und Prozeßwärmeerzeugung, zur Wasserstofferzeugung über Elektrolyse und bei der tertiären Erdölförderung in der Bundesrepublik Deutschland untersucht