54 research outputs found
Symmetry and Topology in Superconductors - Odd-frequency pairing and edge states -
Superconductivity is a phenomenon where the macroscopic quantum coherence
appears due to the pairing of electrons. This offers a fascinating arena to
study the physics of broken gauge symmetry. However, the important symmetries
in superconductors are not only the gauge invariance. Especially, the symmetry
properties of the pairing, i.e., the parity and spin-singlet/spin-triplet,
determine the physical properties of the superconducting state. Recently it has
been recognized that there is the important third symmetry of the pair
amplitude, i.e., even or odd parity with respect to the frequency. The
conventional uniform superconducting states correspond to the even-frequency
pairing, but the recent finding is that the odd-frequency pair amplitude arises
in the spatially non-uniform situation quite ubiquitously. Especially, this is
the case in the Andreev bound state (ABS) appearing at the surface/interface of
the sample. The other important recent development is on the nontrivial
topological aspects of superconductors. As the band insulators are classified
by topological indices into (i) conventional insulator, (ii) quantum Hall
insulator, and (iii) topological insulator, also are the gapped
superconductors. The influence of the nontrivial topology of the bulk states
appears as the edge or surface of the sample. In the superconductors, this
leads to the formation of zero energy ABS (ZEABS). Therefore, the ABSs of the
superconductors are the place where the symmetry and topology meet each other
which offer the stage of rich physics. In this review, we discuss the physics
of ABS from the viewpoint of the odd-frequency pairing, the topological
bulk-edge correspondence, and the interplay of these two issues. It is
described how the symmetry of the pairing and topological indices determines
the absence/presence of the ZEABS, its energy dispersion, and properties as the
Majorana fermions.Comment: 91 pages, 38 figures, Review article, references adde
Protocol for the development of a multidisciplinary clinical practice guideline for the care of patients with chronic subdural haematoma
Introduction: A common neurosurgical condition, chronic subdural haematoma (cSDH) typically affects older people with other underlying health conditions. The care of this potentially vulnerable cohort is often, however, fragmented and suboptimal. In other complex conditions, multidisciplinary guidelines have transformed patient experience and outcomes, but no such framework exists for cSDH. This paper outlines a protocol to develop the first comprehensive multidisciplinary guideline from diagnosis to long-term recovery with cSDH. Methods: The project will be guided by a steering group of key stakeholders and professional organisations and will feature patient and public involvement. Multidisciplinary thematic working groups will examine key aspects of care to formulate appropriate, patient-centered research questions, targeted with evidence review using the GRADE framework. The working groups will then formulate draft clinical recommendations to be used in a modified Delphi process to build consensus on guideline contents. Conclusions: We present a protocol for the development of a multidisciplinary guideline to inform the care of patients with a cSDH, developed by cross-disciplinary working groups and arrived at through a consensus-building process, including a modified online Delphi.</p
Basic science232. Certolizumab pegol prevents pro-inflammatory alterations in endothelial cell function
Background: Cardiovascular disease is a major comorbidity of rheumatoid arthritis (RA) and a leading cause of death. Chronic systemic inflammation involving tumour necrosis factor alpha (TNF) could contribute to endothelial activation and atherogenesis. A number of anti-TNF therapies are in current use for the treatment of RA, including certolizumab pegol (CZP), (Cimzia ®; UCB, Belgium). Anti-TNF therapy has been associated with reduced clinical cardiovascular disease risk and ameliorated vascular function in RA patients. However, the specific effects of TNF inhibitors on endothelial cell function are largely unknown. Our aim was to investigate the mechanisms underpinning CZP effects on TNF-activated human endothelial cells. Methods: Human aortic endothelial cells (HAoECs) were cultured in vitro and exposed to a) TNF alone, b) TNF plus CZP, or c) neither agent. Microarray analysis was used to examine the transcriptional profile of cells treated for 6 hrs and quantitative polymerase chain reaction (qPCR) analysed gene expression at 1, 3, 6 and 24 hrs. NF-κB localization and IκB degradation were investigated using immunocytochemistry, high content analysis and western blotting. Flow cytometry was conducted to detect microparticle release from HAoECs. Results: Transcriptional profiling revealed that while TNF alone had strong effects on endothelial gene expression, TNF and CZP in combination produced a global gene expression pattern similar to untreated control. The two most highly up-regulated genes in response to TNF treatment were adhesion molecules E-selectin and VCAM-1 (q 0.2 compared to control; p > 0.05 compared to TNF alone). The NF-κB pathway was confirmed as a downstream target of TNF-induced HAoEC activation, via nuclear translocation of NF-κB and degradation of IκB, effects which were abolished by treatment with CZP. In addition, flow cytometry detected an increased production of endothelial microparticles in TNF-activated HAoECs, which was prevented by treatment with CZP. Conclusions: We have found at a cellular level that a clinically available TNF inhibitor, CZP reduces the expression of adhesion molecule expression, and prevents TNF-induced activation of the NF-κB pathway. Furthermore, CZP prevents the production of microparticles by activated endothelial cells. This could be central to the prevention of inflammatory environments underlying these conditions and measurement of microparticles has potential as a novel prognostic marker for future cardiovascular events in this patient group. Disclosure statement: Y.A. received a research grant from UCB. I.B. received a research grant from UCB. S.H. received a research grant from UCB. All other authors have declared no conflicts of interes
Escravos ameríndios e negros africanos: uma história conectada. Teorias e modelos de discriminação no império português (ca. 1450-1650)
International competition and domestic cloth in the Ottoman Empire, 1500-1650: a study in undevelopment.
Donated by Klaus KreiserReprinted from : Rewiew, II, 3, Winter 1979
Cham et Noé. Race et esclavage entre judaïsme, christianisme et Islam
Ham and Noe: race, slavery and exegesis in Islam, Judaism, and Christianity.
The biblical story of the drunkenness of Noe and the cursing of Canaan with servitude has offered a pretext for one of the most widespread justifications for racial slavery. How the clear object of the curse, Canaan, became Ham and how Ham, not racially identified in Scripture, became a Black, has long been a puzzle. Through a close examination of early Muslim, Jewish, and Christian versions of the story - focusing on the sources and influence of the great Muslim scholar Tabari (9th- 10th centuries) -, this article identifies the ambiguities and complexities underlying the Bible's transformation. This examination reveals how scriptural exegesis provides a common field for appropriation and polemic. Through a half-conscious exegetical "trialogue" of denial and projection, the religions of Abraham gradually created what Euro-American culture in the age of the Atlantic plantation economy popularized as the Curse of Ham.Le récit biblique de l'ivresse de Noé et la malédiction qui voue Canaan à la servitude furent le prétexte d'une des justifications les plus répandues de l'esclavage des Noirs. Comment l'objet même de la malédiction, Canaan, devint Cham, et comment ce dernier, dont la race n'est pas identifiée par la Bible, devint un Noir, est une question troublante. A travers l'examen serré des plus anciennes versions musulmanes, juives et chrétiennes de cet épisode — spécialement des sources et de l'influence du grand érudit musulman Tabari (IXe-Xe siècles) -, cet article s'attache à cerner les ambiguïtés et les complexités sous-jacentes de cette mutation scripturale. L'analyse met en évidence la manière dont l'exégèse biblique a ouvert le champ libre à la polémique. À travers une triangulation exégétique semi consciente, associant déni de droit, appropriations et projections abusives, les religions du Livre ont graduellement créé les conditions de ce que la culture euro-américaine allait propager, au temps de l'économie atlantique des plantations : la Malédiction de Cham.Braude Benjamin. Cham et Noé. Race et esclavage entre judaïsme, christianisme et Islam. In: Annales. Histoire, Sciences Sociales. 57ᵉ année, N. 1, 2002. pp. 93-125
How significant was the Iberian Jewish contribution to technology and economic life en the Otoman Empire?
Foundation myths of the millet system.
Donated by Klaus KreiserReprinted from : Benjamin Braude; Bernard Lewis. Christians and Jews in the Ottoman Empire
Venture and faith in the commercial life of the Ottoman Balkans, 1500-1650.
Donated by Klaus KreiserReprinted from : The International History Review 7, 1985
Les contes persans de Menasseh Ben Israël. Polémique, apologétique et dissimulation à Amsterdam au XVIIe siècle
The Persian Tales of Menasseh Ben Israel : Polemic, Apologetic, and Dissimulation in Seventeenth-Century Amsterdam.
This article explores one of the most well-known works of modern Jewish letters, Mikveh Yisrael (The Hope of Israel) to reveal that its author produced, not one, but two versions, Esperan de Israel, intended for Sefard audience and, Spes Israelis intended for Gentile audience. The differences between the two 1) demonstrate chronic sensitivity about portraying the Jewish economic role, 2) the subtle vacillation of Marrano discourse between Judaism and Christianity, and 3) the importance of the image of Jewish wealth and power in the lands of Islam in determining the position of Jews in the West. Mikveh Yisrael was benchmark in the changing attitude of European society toward the Jew during the seventeenth and eighteenth centuries.Braude Benjamin, Tomiche Anne. Les contes persans de Menasseh Ben Israël. Polémique, apologétique et dissimulation à Amsterdam au XVIIe siècle. In: Annales. Histoire, Sciences Sociales. 49ᵉ année, N. 5, 1994. pp. 1107-1138
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