Investigation of electronic trap states in organic photovoltaic materials by current-based deep level transient spectroscopy

Current-based deep level transient spectroscopy was used to study trap states in poly(3- hexylthiophene-2,5-diyl) (P3HT), [6,6]-phenyl-C61 butyric acid methyl ester (PCBM) and P3HT:PCBM blend. The obtained spectra showed traps of 87 meV activation energy in pure P3HT and 21 meV for PCBM. The blend shows a complex emission rate spectrum consisting of several different emission rate bands in the range of (0.1-30) s^-1, yielding activation energies between about 30 meV and 160 meV.Comment: 4 pages, 3 figure

Regulation von Apoptose und Überleben durch Signalwege von LMP1 und TNF-Rezeptor 1

TRADD spielt als Adaptermolekül eine zentrale Rolle in der Signaltransduktion von LMP1 und TNF-Rezeptor 1. Während es allerdings durch den TNFR1 neben der Aktivierung verschiedener Signalwege auch zur Induktion von Apoptose und Nekrose kommt, handelt es sich bei LMP1 um ein Protein mit transformierendem Potential. Bei den jeweiligen TRADD-Bindestellen von LMP1 und TNFR1 handelt es sich um zwei strukturell vollkommen unterschiedliche Domänen. Und auch auf der Seite von TRADD wird die Bindung über zwei verschiedene Domänen vermittelt. Im Rahmen dieser Doktorarbeit sollte die Frage beantwortet werden, ob die TRADD-Bindestelle intrinsisch die biologischen Effekte der Signaltransduktion bestimmt oder ob diese durch den Rezeptorkontext festgelegt werden. Zur Beantwortung dieser Frage wurde in einem Domain Swapping Experiment die TRADD-Bindestelle des konstitutiv aktiven LMP1-TNFR1 sowie des TNFR1 gegen die putative TRADD-Bindestelle von LMP1 ausgetauscht. Es konnte erstmals gezeigt werden, dass die Aminosäuren 370-386 die vollständige TRADD-Bindestelle von LMP1 umfassen. Weiter konnte gezeigt werden, dass diese Aminosäuren im LMP1-TNFR1- sowie im TNFR1-Kontext ausreichend sind, um den NF-κB und den JNK1 Signalweg zu aktivieren. Die Aktivierung des JNK1 Signalweges durch LMP1-TNFR1-CTAR2 verläuft unabhängig von TRAF2 und abhängig von TRAF6 und auch die Aktivierung des NF-κB Signalweges durch dieses Rezeptorkonstrukt verläuft TRAF6-abhängig. Damit konnte gezeigt werden, dass die LMP1-spezifischen Charakteristika der Signaltransduktion durch die TRADD-Bindestelle festgelegt und mit ihr zusammen übertragen werden. Obwohl die Aminosäuren 370-386 von LMP1 funktionell sind, sind sie auch im LMP1-TNFR1 sowie im TNFR1 Kontext nicht in der Lage Apoptose zu induzieren. Damit konnte im Rahmen dieser Doktorarbeit gezeigt werden, dass die Aminosäuren 370-386 von LMP1 intrinsisch und unabhängig vom Rezeptorkontext den nicht-apoptotischen Phänotyp der Signaltransduktion festlegen. Außerdem wurde im Rahmen dieser Doktorarbeit die Beteiligung von TRAF7 an der Signaltransduktion von LMP1 untersucht. Dazu wurde traf7 aus einer cDNA kloniert. Zusätzlich wurden verschiedene Deletionsmutanten sowie Fusionen mit dem fluoreszierenden Protein mRFP hergestellt. Es konnte eine Threonin-Phosphorylierung von TRAF7(1-383) nachgewiesen werden. Mittels Fluoreszenzmikroskopie konnte eine Lokalisierung von TRAF7 in vesikulären Strukturen beobachtet werden. Eine Mutante, der der RING- sowie der Zink-Finger fehlen, zeigte hingegen eine gleichmäßige zytosolische Verteilung. Außerdem konnte in dieser Doktorarbeit mit Hilfe von spezifischer siRNA gezeigt werden, dass TRAF7 an der Aktivierung des JNK1 Signalweges durch LMP1 beteiligt ist

Geroch--Kinnersley--Chitre group for Dilaton--Axion Gravity

Kinnersley--type representation is constructed for the four--dimensional Einstein--Maxwell--dilaton--axion system restricted to space--times possessing two non--null commuting Killing symmetries. New representation essentially uses the matrix--valued $SL(2,R)$ formulation and effectively reduces the construction of the Geroch group to the corresponding problem for the vacuum Einstein equations. An infinite hierarchy of potentials is introduced in terms of $2\times 2$ real symmetric matrices generalizing the scalar hierarchy of Kinnersley--Chitre known for the vacuum Einstein equations.Comment: Published in ``Quantum Field Theory under the Influence of External Conditions'', M. Bordag (Ed.) (Proc. of the International Workshop, Leipzig, Germany, 18--22 September 1995), B.G. Teubner Verlagsgessellschaft, Stuttgart--Leipzig, 1996, pp. 228-23

O instituto da violação essencial do contrato à luz da Convenção das Nações Unidas sobre Contratos de Compra e Venda Internacional de Mercadorias (CISG): uma análise doutrinária e jurisprudencial do art. 25 CISG

TCC(graduação) - Universidade Federal de Santa Catarina. Centro de Ciências Jurídicas. Direito.O presente trabalho tem por objetivo analisar, segundo as disposições da Convenção das Nações Unidas sobre os Contratos de Compra e Venda Internacional de Mercadorias (CISG), os requisitos para a caracterização do instituto da violação essencial do contrato, dispostos na redação do art. 25 da CISG, a partir de uma perspectiva teórico-doutrinária e da análise de casos e precedentes sobre a aplicabilidade desse instituto em contratos regulados pela CISG. Para tanto, utiliza-se o método dedutivo. Primeiro aborda-se a evolução legislativa e histórica da CISG, a sua relevância no âmbito do direito do comércio internacional, os seus mecanismos de interpretação e os dos contratos, e a importância da violação essencial do contrato como instrumento para assegurar a continuidade dos contratos regidos pela CISG. Segundo examina-se a evolução legislativa da violação essencial do contrato nos diplomas e projetos antecessores à CISG e a redação do conceito atual que consta no art. 25 da CISG, a partir de um estudo de seus requisitos e da verificação das diferentes observações da comunidade de intérpretes da CISG sobre a redação atual. Terceiro, e por fim, investiga-se a aplicação do instituto da violação essencial do contrato, em especial dos requisitos do art. 25 da CISG, em casos e precedentes de contratos regulados pela CISG.This study aims to analyze according to CISG provisions, the requirements for the characterization of the fundamental breach of the contract, laid out in the wording of art. 25 CISG, from a theoretical-doctrinal perspective and the analysis of cases and precedents on the applicability of this institute in contracts regulated by the CISG. The study was concluded under deductive reasoning. First, the study addresses the legislative and historical evolution of the CISG, its relevance in the field of international trade law, the mechanisms for interpreting the Convention and contracts and the importance of fundamental breach of the contract as an instrument of ensuring the continuity of contracts governed by CISG. Second, it examines the legislative evolution of the fundamental breach of the contract in the diplomas and projects which proceed the CISG and the wording of the current concept contained in art. 25 CISG, based on a study of its requirements and the verification of the different criteria of the CISG community of interpreters of the current wording. Third, and finally, the application of the institute of essential breach of the contract is investigated, in particular regarding the requirements of art. 25 CISG, in cases and precedents of contracts regulated by the CISG

Infinite-dimensional algebras in dimensionally reduced string theory

We examine 4-dimensional string backgrounds compactified over a two torus. There exist two alternative effective Lagrangians containing each two $SL(2)/U(1)$ sigma-models. Two of these sigma-models are the complex and the K\"ahler structures on the torus. The effective Lagrangians are invariant under two different $O(2,2)$ groups and by the successive applications of these groups the affine $\widehat{O}(2,2)$ Kac-Moody is emerged. The latter has also a non-zero central term which generates constant Weyl rescalings of the reduced 2-dimensional background. In addition, there exists a number of discrete symmetries relating the field content of the reduced effective Lagrangians.Comment: 13 pages, Late

Handlungsentlastung oder -belastung? Reflexionen und Referenzen in der universitären Praxis der Lehrer*innenbildung

Reflexivität in der Lehrer*innenbildung ist insbesondere mit Blick auf die Qualitätsoffensive Lehrerbildung eine steigende Bedeutsamkeit zu attestieren – dies zeigt sich bspw. daran, dass an immer mehr universitären Standorten Formate entstehen, die versuchen dem gleichermaßen theoriebegründeten wie programmatischen Anspruch eine reflexive Haltung Studierender zu befördern, gerecht zu werden. Referenzialität, als zentrales Merkmal eines reflexiven (Nach-)Denkens, setzt Reflexionsanlässe (bspw. Fälle aus der unterrichtlichen Praxis) in Bezug zu den Erfahrungen, Wissensbeständen und Haltungen des – zum Reflektieren aufgeforderten – Subjekts. Wir befragen daher in unserem Beitrag zwei Fälle aus der universitären Praxis darauf, welche Referenzbezüge von den Anwesenden als bedeutsam markiert werden – und relationieren unsere Ergebnisse zum kritischen Diskurs einer in qualitativ-rekonstruktiver Forschungstradition stehenden Lehrer*innenbildung. (DIPF/Orig.

Comparison of HER2 Expression in Primary Tumor and Disseminated Tumor Cells in the Bone Marrow of Breast Cancer Patients

Objective: The aim of this study was to measure the human epidermal growth factor receptor 2 (HER2) status of disseminated tumor cells (DTCs) from bone marrow (BM) aspirates and to assess correspondence or discrepancy with the primary tumor. Methods: DTCs were isolated from the BM of 156 breast cancer patients. Cytokeratin-positive DTCs were further analyzed by the chromogenic in situ hybridization method to detect HER2 gene amplification. Results: A significant correlation (p = 0.021) was found between the HER2 status of DTCs and the primary tumors. Sixty-one (68.5%) patients had a corresponding status. However, a shift of phenotype between primary tumor and DTCs was found in the remaining patients. Conclusion: This study showed a significant grade of discordance of the HER2 status between primary tumors and DTCs in the BM of a relevant subgroup of patients. Detection of HER2 amplification on DTCs could therefore help to better stratify patients for a more tailored therapy, since they would benefit from a HER2-targeted therapy. (C) 2016 S. Karger AG, Base

The Ernst Equation on a Riemann Surface

The Ernst equation is formulated on an arbitrary Riemann surface. Analytically, the problem reduces to finding solutions of the ordinary Ernst equation which are periodic along the symmetry axis. The family of (punctured) Riemann surfaces admitting a non-trivial Ernst field constitutes a ``partially discretized'' subspace of the usual moduli space. The method allows us to construct new exact solutions of Einstein's equations in vacuo with non-trivial topology, such that different ``universes'', each of which may have several black holes on its symmetry axis, are connected through necks bounded by cosmic strings. We show how the extra topological degrees of freedom may lead to an extension of the Geroch group and discuss possible applications to string theory.Comment: 22 page

Colliding Wave Solutions, Duality, and Diagonal Embedding of General Relativity in Two-Dimensional Heterotic String Theory

The non-linear sigma model of the dimensionally reduced Einstein (-Maxwell) theory is diagonally embedded into that of the two-dimensional heterotic string theory. Consequently, the embedded string backgrounds satisfy the (electro-magnetic) Ernst equation. In the pure Einstein theory, the Matzner-Misner SL(2,{\bf R}) transformation can be viewed as a change of conformal structure of the compactified flat two-torus, and in particular its integral subgroup SL(2,{\bf Z}) acts as the modular transformation. The Ehlers SL(2,{\bf R}) and SL(2,{\bf Z}) similarly act on another torus whose conformal structure is induced through the Kramer-Neugebauer involution. Either of the Matzner-Misner and the Ehlers SL(2,{\bf Z}) can be embedded to a special T-duality, and if the former is chosen, then the Ehlers SL(2,{\bf Z}) is shown to act as the S-duality on the four-dimensional sector. As an application we obtain some new colliding string wave solutions by using this embedding as well as the inverse scattering method.Comment: 32 pages, revte

Detection of Tumor Cell-Specific mRNA in the Peripheral Blood of Patients with Breast Cancer-Evaluation of Several Markers with Real-Time Reverse Transcription-PCR

It is widely known that cells from epithelial tumors, e. g., breast cancer, detach from their primary tissue and enter blood circulation. We show that the presence of circulating tumor cells (CTCs) in samples of patients with primary and metastatic breast cancer can be detected with an array of selected tumor-marker-genes by reverse transcription real-time PCR. The focus of the presented work is on detecting differences in gene expression between healthy individuals and adjuvant and metastatic breast cancer patients, not an accurate quantification of these differences. Therefore, total RNA was isolated from blood samples of healthy donors and patients with primary or metastatic breast cancer after enrichment of mononuclear cells by density gradient centrifugation. After reverse transcription real-time PCR was carried out with a set of marker genes (BCSP, CK8, Her2, MGL, CK18, CK19). B2M and GAPDH were used as reference genes. Blood samples from patients with metastatic disease revealed increased cytokine gene levels in comparison to normal blood samples. Detection of a single gene was not sufficient to detect CTCs by reverse transcription real-time PCR. Markers used here were selected based on a recent study detecting cancer cells on different protein levels. The combination of such a marker array leads to higher and more specific discovery rates, predominantly in metastatic patients. Identification of CTCs by PCR methods may lead to better diagnosis and prognosis and could help to choose an adequate therapy