Non-linear IVIV characteristics in two-dimensional superconductors: Berezinskii-Kosterlitz-Thouless physics vs inhomogeneity

One of the hallmarks of the Berezinskii-Kosterlitz-Thouless (BKT) transition in two-dimensional (2D) superconductors is the universal jump of the superfluid density, that can be indirectly probed via the non-linear exponent of the current-voltage $IV$ characteristics. Here, we compare the experimental measurements of $IV$ characteristics in two cases, namely NbN thin films and SrTiO$_3$-based interfaces. While the former display a paradigmatic example of BKT-like non-linear effects, the latter do not seem to justify a BKT analysis. Rather, the observed $IV$ characteristics can be well reproduced theoretically by modelling the effect of mesoscopic inhomogeneity of the superconducting state. Our results offer an alternative perspective on the spontaneous fragmentation of the superconducting background in confined 2D systems.Comment: Final version, as publishe

Benigne zystische Raumforderungen des Hodens: Eine Übersicht

Zusammenfassung: Hodenzysten werden im Rahmen der skrotalen Sonographie zunehmend diagnostiziert. Grund hierfür ist u.a. die flächendeckende Verfügbarkeit moderner, hochauflösender Ultraschallgeräte. Differentialdiagnostisch und ätiologisch sind benigne und maligne Erkrankungen mit testikulärer Zystenbildung voneinander zu unterscheiden. Benigne Krankheitsbilder mit zystischen Raumforderungen des Hodens sind die tubuläre Ektasie des Rete testis, die zystische Dysplasie, Epidermoidzysten, einfache intraparenchymatöse Hodenzysten und Zysten der Tunica albuginea. Die testikuläre Dermoidzyste, die lange Zeit zu Unrecht als potentiell maligne angesehen wurde, ist ebenfalls als benigne zu klassifizieren. Bei Diagnose einer benignen zystischen Raumforderung des Hodens kann in den meisten Fällen eine organerhaltende operative Therapie oder ein abwartendes, überwachendes Procedere empfohlen werde

Competition between electron pairing and phase coherence in superconducting interfaces

In LaAlO3/SrTiO3 heterostructures, a gate tunable superconducting electron gas is confined in a quantum well at the interface between two insulating oxides. Remarkably, the gas coexists with both magnetism and strong Rashba spin–orbit coupling. However, both the origin of superconductivity and the nature of the transition to the normal state over the whole doping range remain elusive. Here we use resonant microwave transport to extract the superfluid stiffness and the superconducting gap energy of the LaAlO3/SrTiO3 interface as a function of carrier density. We show that the superconducting phase diagram of this system is controlled by the competition between electron pairing and phase coherence. The analysis of the superfluid density reveals that only a very small fraction of the electrons condenses into the superconducting state. We propose that this corresponds to the weak filling of high- energy dxz/dyz bands in the quantum well, more apt to host superconductivity

First-principles study of orthorhombic CdTiO3 perovskite

In this work we perform an ab-initio study of CdTiO3 perovskite in its orthorhombic phase using FLAPW method. Our calculations help to decide between the different cristallographic structures proposed for this perovskite from X-Ray measurements. We compute the electric field gradient tensor (EFG) at Cd site and obtain excellent agreement with available experimental information from a perturbed angular correlation (PAC) experiment. We study EFG under an isotropic change of volume and show that in this case the widely used "point charge model approximation" to determine EFG works quite well.Comment: 4 pages, 1 figure. Accepted in Physical Review

Effects of insert geometry and feed rate on quality characteristics of turned parts

This paper investigates experimentally and analytically the influence of insert geometry and feed rate on the quality characteristics of turned parts under the dry cutting condition. A three-level, three-parameter experiment was planned using the design of experiment methodology. The three levels of independent input parameters were: insert shape - rhombus, triangle, and square; nose radius 0.4, 0.8, and 1.2 mm; and feed rate - 0.11, 0.22 and 0.33 mm/rev. The measured output parameters were the three most widely used quality characteristics of turned parts-diameter error, circularity and surface finish (arithmetic average). The results were analyzed using three methods: traditional analysis, Pareto analysis of variation and Taguchi method. The results reveal that two of the selected tool geometry parameters, insert shape and nose radius, influence diameter error considerably (total contribution 66.97%) and have minor effects on circularity (total contribution 3.67%) and surface finish (total contribution 11.60%). Feed rate is the major contributor to surface finish (76.42% contribution), whereas circularity is dominated by interaction effects such as insert shape-feed rate interaction (31.44% contribution). © 2015 World Scientific Publishing Company

Development of OMP based indirect ELISA to gauge the antibody titers in bovines against Pasteurella multocida

Summary Pasteurella multocida (P. multocida) is an important pathogen of various domestic animals. The outer membrane proteins (OMPs) play a major role in pathogenesis and immunogenicity of P. multocida. The aim of the study was to develop indirect enzyme linked immuno sorbant assay (ELISA) based on OMPs to ascertain the antibody titers in animals post-infection or to gauge the potency of vaccine. The OMPs were extracted and purified from P. multocida P:52 (vaccine strain) and P. multocida B:2 isolated from natural outbreak of Haemorrhagic septicaemia (HS) and analyzed on SDS PAGE and through western blot. The OMPs profile of the vaccine strain and the isolate from the natural outbreak of HS were found to be similar. Optimization of various components viz. coating antigens, anti-species conjugate, etc. were carried out against both anti-P. multocida hyper immune and pre immune serum. Validation of OMP based indirect ELISA assay to measure immune response against P. multocida in bovine revealed 91% diagnostic sensitivity (DSN) and about 100% diagnostic specificity (DSP) at 25% cut off. OMP based indirect ELISA was found to be more specific, but less sensitive as compared to WCL based assay

Cultural diversity teaching and issues of uncertainty: the findings of a qualitative study

BACKGROUND: There is considerable ambiguity in the subjective dimensions that comprise much of the relational dynamic of the clinical encounter. Comfort with this ambiguity, and recognition of the potential uncertainty of particular domains of medicine (e.g.--cultural factors of illness expression, value bias in diagnoses, etc) is an important facet of medical education. This paper begins by defining ambiguity and uncertainty as relevant to clinical practice. Studies have shown differing patterns of students' tolerance for ambiguity and uncertainty that appear to reflect extant attitudinal predispositions toward technology, objectivity, culture, value- and theory-ladeness, and the need for self-examination. This paper reports on those findings specifically related to the theme of uncertainty as relevant to teaching about cultural diversity. Its focus is to identify how and where the theme of certainty arose in the teaching and learning of cultural diversity, what were the attitudes toward this theme and topic, and how these attitudes and responses reflect and inform this area of medical pedagogy. METHODS: A semi-structured interview was undertaken with 61 stakeholders (including policymakers, diversity teachers, students and users). The data were analysed and themes identified. RESULTS: There were diverse views about what the term cultural diversity means and what should constitute the cultural diversity curriculum. There was a need to provide certainty in teaching cultural diversity with diversity teachers feeling under considerable pressure to provide information. Students discomfort with uncertainty was felt to drive cultural diversity teaching towards factual emphasis rather than reflection or taking a patient centred approach. CONCLUSION: Students and faculty may feel that cultural diversity teaching is more about how to avoid professional, medico-legal pitfalls, rather than improving the patient experience or the patient-physician relationship. There may be pressure to imbue cultural diversity issues with levels of objectivity and certainty representative of other aspects of the medical curriculum (e.g.--biochemistry). This may reflect a particular selection bias for students with a technocentric orientation. Inadvertently, medical education may enhance this bias through training effects, and accommodate disregard for subjectivity, over-reliance upon technology and thereby foster incorrect assumptions of objective certainty. We opine that it is important to teach students that technology cannot guarantee certainty, and that dealing with subjectivity, diversity, ambiguity and uncertainty is inseparable from the personal dimension of medicine as moral enterprise. Uncertainty is inherent in cultural diversity so this part of the curriculum provides an opportunity to address the issue as it relates to patient care