334 research outputs found

    The antiferromagnetic phase of the Floquet-driven Hubbard model

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    A saddle point plus fluctuations analysis of the periodically driven half-filled two-dimensional Hubbard model is performed. For drive frequencies below the equilibrium gap, we find discontinuous transitions to time-dependent solutions. A highly excited, generically non-thermal distribution of magnons occurs even for drive frequencies far above the gap. Above a critical drive amplitude, the low-energy magnon distribution diverges as the frequency tends to zero and antiferromagnetism is destroyed, revealing the generic importance of collective mode excitations arising from a non-equilibrium drive

    The challenging future for restraint in US foreign policy

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    There has been a growing debate over restraint in US foreign policy, fueled most recently by President Trump’s removal of troops from Syria last year. But, writes C. William Walldorf, Jr., those who wish to see more restraint in US foreign policy face domestic challenges: partisanship, and the need to be seen to be against the other side, the desire by many Americans to uphold democratic values abroad,and the risk of being seen as “soft” on national security

    Thermoelectrics in Coulomb-coupled quantum dots: Cotunneling and energy-dependent lead couplings

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    We study thermoelectric effects in Coulomb-coupled quantum-dot (CCQD) systems beyond lowest-order tunneling processes and the often applied wide-band approximation. To this end, we present a master-equation (ME) approach based on a perturbative TT-matrix calculation of the charge and heat tunneling rates and transport currents. Applying the method to transport through a non-interacting single-level QD, we demonstrate excellent agreement with the Landauer-B{\"u}ttiker theory when higher-order (cotunneling) processes are included in the ME. Next, we study the effect of cotunneling and energy-dependent lead couplings on the heat currents in a system of two Coulomb-coupled QDs. Overall, we find that cotunneling processes (i) dominate the heat currents at low temperature and bias, and (ii) give rise to a pronounced reduction of the cooling power achievable with the recently demonstrated Maxwell's demon cooling mechanism. Furthermore, we demonstrate that the cooling power can be boosted significantly by carefully engineering the energy dependence of the lead couplings to filter out undesired transport processes. Our findings emphasize the importance of considering higher-order cotunneling processes as well as the advantage of engineered energy-dependent lead couplings in the optimization of the thermoelectric performance of Coulomb-coupled QD systems

    Mission and new evangelisation in Europe : outlines of contextual concepts of mission [1979-1992]

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    Text in GermanThis thesis analyses the contextual concepts for Mission in Europe as developed by European churches between 1979 and 1992 by examining their interpretation of European culture and history (,,Europabild") and the corresponding understandings of mission. The main thrust of the Roman Catholic concept of the ,,New Evangelization of Europe" is to understand European-humanist culture as having grown out of christian (Roman Catholic) roots and to interpret the Church as Soul of Europe. Accordingly, New Evangelization means to call Europe back to the Church in order to keep its culture from ruin and to revitalize it. The European branch of the Lausanne Movement took some clues from the Roman Catholic concept, but interpreted them in its own way since 1984. Here European culture is understood in the basic theological tension between ,,bridge" and ,,barrier" for the Gospel in Europe. The aim of mission is the conversion of Europeans to the biblical and present Jesus Christ who is able to give new life and new hope for individual Europeans and European culture. The Conference of European Churches has coined and discussed the concept of ,,Mission of the Churches in a Secularized Europe" since 1986. The Protestant ,,wing" tends to be less critical towards secularized European culture than Orthodox theologians seem to be. Nevertheless both affirm an understanding of mission as encounter with present time European culture in which God is seen at work in various and mysterious ways. Finally the author formulates his conclusions and perspectives for a transforming (of) mission in Europe. The Body of Jesus Christ in Europe needs to be as deeply rooted in biblical revelation as in biblical spirituality in order to live as a missionary and alternative community in the middle of European culture, and in order to not repeat past european-christian inculturations, but to repent and invite Europeans to turn to Jesus Christ to explore fresh ways of life, hope and reconciliation in the middle of European diversity.Diese Arbeit fragt nach den theologischen und historischen Grundlinien kontextueller Missionskonzepte filr Europa, wie sie zwischen 1979 und 1992 in den Kirchen Europas entwickelt wurden. In einer ein:f:Uhrenden Standortbestimmung werden zunachst Diskontinuitat und Kontinuitat eines auf Europa bezogenen Missionsverstandnisses in der Missions- und Kirchengeschichte dargestellt. Im Hauptteil der Arbeit werden in einem historisch-theologischen Untersuchungsgang die verschiedenen Missionskonzepte fUr Europa nach ihrem Europabild und dem korrespondierenden Missionsverstandnis befragt. Im romisch-katholischen Programm der ,,Neuevangelisierung Europas", das seit 1979 von Papst Johannes Paul II. inspiriert wird, geht es darum, die christliche (romisch-katholische) Kirche als Wurzel und Seele der europaisch-humanistischen Kultur zu erkennen und sich ihr neu zuzuwenden, um so die europaische Kultur vor dem Zerfall zu bewahren. Der europaische Zweig der evangelikalen Lausanner Bewegung hat Impulse aus der romischkatholischen Kirche aufgenommen und seit 1984 in einer Reihe von Konferenzen in eigener Weise fortgefuhrt. Hier wird die Kultur Europas in der Spannung zwischen Silnde und Erlosung und somit als Herausforderung und Chance fUr eine speziell auf die europaische Situation ausgerichtete Mission verstanden. Ziel der Mission ist es, die Europaer zur Umkehr zu Jesus Christus einzuladen, der alleine Grund fUr neues Leben und neue Hoffnung in der Kultur Europas sein konne. Die Konferenz der Europaischen Kirchen, der ein gro.Ber Teil der protestantischen und orthodoxen Kirchen Europas angehOrt, beschaftigt sich seit 1986 in einer Reihe von Studienkonsultationen mit der ,,Mission der Kirchen in einem sirkularisierten Europa". Die protestantischen Delegierten stehen der sirkularisierten Kultur Europas weniger kritisch gegeniiber als die orthodoxen Vertreter. Insgesamt versteht man Mission in Europa als Begegnung mit der europaischen Kultur der Gegenwart, in der man Gottes Wirken entdecken konne. Ausgehend von diesen Ergebnissen werden in einem Schlussteil Grundlinien fur ein erneuerte und erneuernde Mission in Europa formuliert. Die missionarische Gemeinde in Europa heute braucht die Verwurzelung in der biblischen Offenbarung und in biblischer Spiritualitat, um als Mit-, Gegenund Fur-Kultur inmitten von Europa nicht zu einer Riickkehr zu vergangenen christlichen Inkulturationen, sondern zur Umkehr zum lebendigen Christus einzuladen, der neues Leben und neue Hoffnung schenkt und Versohnung inmitten aller europaischen Verschiedenheit moglich macht.Christian Spirituality, Church History and MissiologyD.Th. (Missiology

    Drosophila Homeodomain-Interacting Protein Kinase (Hipk) Phosphorylates the Hippo/Warts Signalling Effector Yorkie

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    Developmental growth and patterning are regulated by an interconnected signalling network of several pathways. In Drosophila, the Warts (Wts) kinase, a component of the Hippo signalling pathway, plays an essential role in regulating transcription and growth by phosphorylating its substrate Yorkie (Yki). The phosphorylation of Yki critically influences its localisation and activity as a transcriptional coactivator. In this study, we identified the homeodomain-interacting protein kinase (Hipk) as another kinase that phosphorylates Yki and mapped several sites of Yki phosphorylated by Hipk, using in vitro analysis: Ser168, Ser169/Ser172 and Ser255. These sites might provide auxiliary input for Yki regulation in vivo, as transgenic flies with mutations in these show prominent phenotypes; Hipk, therefore, represents an additional upstream regulator of Yki that works in concert with Wts

    Sevesorapport för ny verksamhet - Hur man upprÀttar en sÀkerhetsrapport nÀr anlÀggningen Àr i planeringsstadiet

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    To reduce the risk of serious chemical accidents to occur there is a legislation called the Seveso-legislation. One part of this legislation demands that all business that handle certain amounts of chemical compounds to submit a safety report in order to get permission to run their business. The safety report should contain over-all plans of how to handle safety as well as detailed descriptions of several accident scenarios. If one wants to build a new chemical facility the safety report is supposed to be handed in when applying for a permit to run the operation. This often has to be done long in advance. The problem that this report focuses on is how to develop a safety report when you don’t know how the facility will look or operate. By examining and interpreting the legislation and conducting interviews with representatives from agencies and companies a possible solution is presented. The proposed solution is to produce a safety report in two steps. In the first step a preliminary safety report is developed and sent in to the authorities. The second is to continue to develop the safety report as planning and building progresses and more data about the facility becomes known. This way you can present a safety report in an early stage but one still have the opportunity to improve the safety report as information becomes available. One important part of this report is the attempt to find a minimum level of the information in a safety report. To know this is important to companies to make the application process more predictable and clear. It is important to remember to not stop the work on the safety report if step one gets accepted by the authorities, the safety could be at risk if one does not continue the work with the safety report

    The Drosophila homeodomain transcription factor Homeobrain is involved in the formation of the embryonic protocerebrum and the supraesophageal brain commissure

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    During the embryonic development of Drosophila melanogaster many transcriptional activators are involved in the formation of the embryonic brain. In our study we show that the transcription factor Homeobrain (Hbn), a member of the 57B homeobox gene cluster, is an additional factor involved in the formation of the embryonic Drosophila brain. Using a Hbn antibody and specific cell type markers a detailed expression analysis during embryonic brain development was conducted. We show that Hbn is expressed in several regions in the protocerebrum, including fibre tract founder cells closely associated with the supraesophageal brain commissure and also in the mushroom bodies. During the formation of the supraesophageal commissure, Hbn and FasII-positive founder cells build an interhemispheric bridge priming the commissure and thereby linking both brain hemispheres. The Hbn expression is restricted to neural but not glial cells in the embryonic brain. In a mutagenesis screen we generated two mutant hbn alleles that both show embryonic lethality. The phenotype of the hbn mutant alleles is characterized by a reduction of the protocerebrum, a loss of the supraesophageal commissure and mushroom body progenitors and also by a dislocation of the optic lobes. Extensive apoptosis correlates with the impaired formation of the embryonic protocerebrum and the supraesophageal commissure. Our results show that Hbn is another important factor for embryonic brain development in Drosophila melanogaster

    The homeodomain transcription factor Orthopedia is involved in development of the Drosophila hindgut

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    Background The Drosophila hindgut is commonly used model for studying various aspects of organogenesis like primordium establishment, further specification, patterning, and morphogenesis. During embryonic development of Drosophila, many transcriptional activators are involved in the formation of the hindgut. The transcription factor Orthopedia (Otp), a member of the 57B homeobox gene cluster, is expressed in the hindgut and nervous system of developing Drosophila embryos, but due to the lack of mutants no functional analysis has been conducted yet. Results We show that two different otp transcripts, a hindgut-specific and a nervous system-specific form, are present in the Drosophila embryo. Using an Otp antibody, a detailed expression analysis during hindgut development was carried out. Otp was not only expressed in the embryonic hindgut, but also in the larval and adult hindgut. To analyse the function of otp, we generated the mutant otp allele otpGT by ends-out gene targeting. In addition, we isolated two EMS-induced otp alleles in a genetic screen for mutants of the 57B region. All three otp alleles showed embryonic lethality with a severe hindgut phenotype. Anal pads were reduced and the large intestine was completely missing. This phenotype is due to apoptosis in the hindgut primordium and the developing hindgut. Conclusion Our data suggest that Otp is another important factor for hindgut development of Drosophila. As a downstream factor of byn Otp is most likely present only in differentiated hindgut cells during all stages of development rather than in stem cells

    Die Neuevangelisierung Europas : eine missiologische Studie zu ihren Grundlinien in der römisch-katholischen Kirche, 1979-1991

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    This paper investigates the contours of the program of New Evangelisation of Europe (NEE) in the Roman-Catholic Church. While the roots lie with Vatican II and Paul VI.'s Evangelii Nuntiandi, the concept itself was developed by Pope John Paul II., the European Council of Bishops (CCEE) and the Bishops' Special Synod on Europe in 1991. The concept sees European culture as having been born out of Catholic Christianity. Postchristian Europe therefore is judged as having lost its (catholic) soul. This becomes evident in a reduction of humanness in the personal, cultural and spiritual realm. Therefore official Catholic teaching outlines NEE as personal spiritual renewal, catholic unity and cultural transformation. Source, norm and bearer of the NEE is the Roman-Catholic church. The author however thinks that genuine renewal springs from God's Word and Spirit (missio Dei), creating communities of faith, transforming both, church and culture in Europe.Viele Jahrhunderte lang sahen die europaischen Kirchen ihren Kontinent und ihre Kultur als corpus Christianum. ,,Mission" galt nur den ,,Heiden" in Obersee. Diese Sicht geriet im Laufe des 20. Jahrhunderts ins Wanken. Imrner mehr Stimrnen fragten: ist nicht auch Europa ,,Missionfeld"? Inzwischen sind sich die meisten kirchlichen Traditionen in Europa einig, dal3 sie es mit einer ,,nachchristlichen" oder ,,neuheidnischen" Kultur zu tun haben, die emeut missionarisch mit dem Evangelium durchdrungen werden mu13. Die vorliegende Arbeit mochte die Konturen und Grundlinien des romisch-katholischen Programmes der Neuevangelisierung Europas (NEE) verstehen, darstellen und kritisch wurdigen. Die Arbeit besteht aus sechs Hauptteilen. Im ersten Teil werden grundlegende missiologische Aussagen des II. Vatikanischen Konzils und das Schreiben Papst Pauls VI. Evangelii Nuntiandi als Hintergrund und Wurzel fur das Konzept der NEE interpretiert. Im zweiten Teil stelle ich die Entwicklung der NEE im Denken Johannes Pauls II. seit 1979 dar, wahrend ich mich im dritten Teil auf die Interpretation der NEE auf den Symposien des Rates der Europaischen Bischofskonferenzen (CCEE) von 1982-1989 konzentriere. In verschiedenen Nuancen heben sich die Interpretationen der Bischfofe von den Gedanken Papst Johannes Pauls II. ab, ohne jedoch grundlegende Widerspriiche zu erzeugen. Im vierten T eil zeichne ich die Gedankengange zur NEE anhand der Abschlu13erklarung der Sondersynode der Bischofe fur Europa von 1991 nach. Die Synode stellt einen unspektakularen Hohepunkt, eine gewisse Zasur und eine ausgewogene Zusamrnenfassung der Entwicklung des Konzeptes dar. Eine systematische Zusamrnenfassung der Grundlinien der NEE bildet den funften Teil. Es wird deutlich, da13 die NEE die gesamte missionarische Existenz der romischkatholischen Kirche in Europa in all ihrer Vielfalt umfasst, um dem Ziel geistlicher, kirchlicher und kultureller Emeuerung im eschatologischen Horizont des Reiches Gottes naherzukommen. Im abschlie13enden Teil versuche ich das Konzept der Neuevangelisierung Europas anhand verschiedener missiologischer Modelle einzuordnen und aus evangelikaler Sicht kritisch zu wlirdigen. Die Starke des Konzeptes sehe ich im kulturbezogenen Ruf zur Urnkehr aus gottlosem und destruktivem Glauben, Denken und Handeln und der Verkiindigung der Hinkehr zu Jesus Christus, die sich in alle Bereiche der Kultur auswirkt und somit Europa mit neuer Hoffnung und Zukunft erfullen kann. Die Schwache des (offiziellen) Konzeptes sehe ich darin, da13 die romisch-katholische Kirche m.E. zur Norm fur die Emeuerung gemacht wird. Umfassende Emeuerung jedoch geht von Gottes Wort und Geist (missio Dei) aus, der Kirche und Kultur verandert und erneuert.Christian Spirituality, Church History and MissiologyM.Th. (Missiology
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