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Non-Abelian Statistics in one dimension: topological momentum spacings and SU(2) level k fusion rules
No full textWe use a family of critical spin chain models discovered recently by one of us [M. Greiter, Map-
ping of Parent Hamiltonians, Springer, Berlin/Heidelberg 2011] to propose and elaborate that non-
Abelian, SU(2) level k = 2S anyon statistics manifests itself in one dimension through topological
selection rules for fractional shifts in the spacings of linear momenta, which yield an internal Hilbert
space of, in the thermodynamic limit degenerate states. These shifts constitute the equivalent to the
fractional shifts in the relative angular momenta of anyons in two dimensions. We derive the rules
first for Ising anyons, and then generalize them to SU(2) level k anyons. We establish a one-to-one
correspondence between the topological choices for the momentum spacings and the fusion rules of
spin 1 2 spinons in the SU(2) level k Wess–Zumino–Witten model, where the internal Hilbert space is
spanned by the manifold of allowed fusion trees in the Bratelli diagrams. Finally, we show that the
choices in the fusion trees may be interpreted as the choices between different domain walls between
the 2S + 1 possible, degenerate dimer configurations of the spin S chains at the multicritical poin
Quantitative evaluation of inflammatory and immune responses in the early stages of chronic Helicobacter pylori infection
No full textThe early consequences of Helicobacter pylori infection and the role of bacterial virulence determinants in disease outcome remain to be established. The present study sought to measure the development of host inflammatory and immune responses and their relationship to the putative bacterial virulence factors cag pathogenicity island (cagPAI), vacA allele, and oipA in combination with bacterial colonization density in a feline model of the early stages of H. pylori infection. Gastric tissues obtained from infected and uninfected cats were evaluated for H. pylori ureB, cagPAI, vacA allele, and oipA and colonization density (urease, histology, and real-time PCR). Inflammation was assessed by measuring mRNA upregulation of gamma interferon (IFN-γ), interleukin (IL)-1α, IL-1β, IL-4, IL-6, IL-8, IL-10, and IL-12 p40 and histopathology. The mucosal immune response was characterized by morphometric analysis of lymphoid follicles and by differentiating lymphocyte populations with antibodies against surface markers. Infecting H. pylori strains were positive for vacAs1 but lacked cagPAI and an active oipA gene. Colonization density was uniform throughout the stomach. Upregulation of IFN-γ, IL-1α, IL-1β, and IL-8 and increased severity of inflammatory infiltrates and fibrosis were observed in infected cats. The median number and total area of lymphoid aggregates were 5 and 10 times greater, respectively, in the stomachs of infected than uninfected cats. Secondary lymphoid follicles in uninfected cats were rare and positive for BLA.36 and B220 but negative for CD3 and CD79α, whereas in infected cats they were frequent and positive for BLA.36, CD79α, and CD3 but negative for B220. Upregulation of IFN-γ, IL-1α, IL-1β, and IL-8 and marked hyperplasia of secondary lymphoid follicles are early consequences of H. pylori infection in cats. The response appears to be similar to that of infected people, particularly children, can develop independently of the pathogenicity factors cagPAI and oipA, and is not correlated with the degree of colonization density or urease activity
Association of Helicobacter with cholangiohepatitis in cats
No full textInfection with Helicobacter spp. is increasingly linked with hepatobiliary inflammation and neoplasia in people and in a variety of animals. We sought to determine if Helicobacter species infection is associated with cholangiohepatitis in cats. Deoxyribonucleic acid was extracted from tissue blocks from cats with cholangiohepatitis (32), noninflammatory liver disease (13), and cats with normal liver histology (4). Deoxyribonucleic acid was polymerase chain reaction-amplified with 2 sets of Helicobacter genus-specific primers, gel purified, and sequenced. Polymerase chain reaction-positive hepatic tissue was further examined with Steiner's stain, immunocytochemistry for Helicobacter species, and eubacterial fluorescent in situ hybridization. Gastric tissues of cats with known Helicobacter infection status served as controls for deoxyribonucleic acid extraction and sequence comparison. Helicobacter species were detected in 2/32 cats with cholangiohepatitis, and 1/17 controls. Sequences had 100% identity with Helicobacter species liver, Helicobacter pylori, and Helicobacter fenelliae/cinaedii in a cat with suppurative cholangitis, Helicobacter species liver, Helicobacter pylori, and Helicobacter nemistrineae in a cat with mild lymphocytic portal hepatitis, and Helicobacter bilis in a cat with portosystemic vascular anomaly. In contrast, sequences from gastric biopsies showed highest homology (99-100%) to "Helicobacter heilmannii," Helicobacter bizzozeronii, Helicobacter felis, and Helicobacter salomonis. Fluorescent in situ hybridization revealed a semicurved bacterium, with Helicobacter-like morphology, in an intrahepatic bile duct of the cat with suppurative cholangitis. This study has identified Helicobacter deoxyribonucleic acid in 2/32 cats with cholangiohepatitis and 1/13 cats with noninflammatory liver disease. Deoxyribonucleic acid sequences of hepatic Helicobacter species were distinct from those found in the stomach and are broadly consistent with those identified in cat intestine and bile, and hepatobiliary disease in people and rodents. Copyrigh
Approaches to learning leadership development in different school systems
No full textThis chapter presents a selection of the leadership initiatives and analyses gathered through the Innovative Learning Environments project. Tanja Westfall-Greiter describes the strategy of creating teacher learning leaders (lerndesigners) in the current Austrian reform (Neue Mittelschule or NMS). Judy Halbert and Linda Kaser discuss a leadership programme in British Columbia, Canada that engages leaders together in a "spiral of inquiry" about learning in their own school and networked activity across sites. The New York City examples described by Roser Salavert cover Professional Learning Communities, coaching, teacher teams, and student "voice". Lone Christiansen and Per Tronsmo present Norwegian approaches to leadership, and national programmes for school leadership professional development and the Advisory Team programme for mentoring principals and local providers. The South Australian and Israeli examples presented by Susanne Owen and Dorit Tubin feature the work of particular sections of the education ministries looking to drive innovative learning and provide conditions to support it
Identification and tracking of sturgeons and paddlefish products in trade: Implications for trade control and biodiversity management
No full textDespite strict protection of natural populations and CITES restrictions on international trade of caviar, sturgeons are increasingly at risk of extinction. The latest assessment released in July 2022 by the IUCN confirms sturgeons and paddlefish as the most endangered group of species on the planet. In this context, poaching and the illegal trade of caviar and meat have a significant weight and it is, therefore, necessary to support control activities by identifying diagnostic and reliable methods for the identification of species, interspecific hybrids, aquaculture or natural origin and geographical provenance of commercial samples. The technical approaches used for this purpose now include biochemical, isotopic, and genetic marker analyses, and are constantly evolving with remarkable developments proposed in recent years. Among these, particularly relevant are the numerous nuclear genetic markers, which allow the identification not only of pure sturgeon species but also of interspecific hybrids and the approaches based on the analysis of fatty acids which allow to distinguish feed-fed animals from fed with natural food. Additionally, the use of multi-isotopic fingerprint analyzes to determine the geographical area of origin is rapidly developing and is proving to be extremely useful for commercial controls and for the protection of natural sturgeon populations.This synthesis arises from the need of providing an exhaustive picture of the available technical approaches and to evaluate their potential and limits, focusing mainly on the innovations proposed in the last 10 years which have significantly improved our diagnostic power
Measurement techniques for tracer kinetic studies with stable isotopes of zirconium
No full textBiokinetic models are used in radiation protection to assess internal radiation doses. Experiments with stable isotopes as tracers can be performed to obtain characteristic parameters of these models. Two methods for the measurement of zirconium isotopes in human biological samples are presented - thermal ionisation mass spectrometry (TIMS) and proton nuclear activation analysis (PNA). Descriptions include sample preparation, operating conditions, relative uncertainties and method detection limits as well as important properties of both methods
Turbulent hydrodynamics in strongly correlated Kagome metals
No full textA current challenge in condensed matter physics is the realization of strongly correlated, viscous electron fluids. These fluids can be described by holography, that is, by mapping them onto a weakly curved gravitational theory via gauge/gravity duality. The canonical system considered for realizations has been graphene. In this work, we show that Kagome systems with electron fillings adjusted to the Dirac nodes provide a much more compelling platform for realizations of viscous electron fluids, including non-linear effects such as turbulence. In particular, we find that in Scandium Herbertsmithite, the fine-structure constant, which measures the effective Coulomb interaction, is enhanced by a factor of about 3.2 as compared to graphene. We employ holography to estimate the ratio of the shear viscosity over the entropy density in Sc-Herbertsmithite, and find it about three times smaller than in graphene. These findings put the turbulent flow regime described by holography within the reach of experiments. Viscous electron fluids are predicted in strongly correlated systems but remain challenging to realize. Here, the authors predict enhanced effective Coulomb interaction and reduced ratio of the shear viscosity over entropy density in a Kagome metal, inferring turbulent flow of viscous electron fluids
Aufnahme und relativer Transport von homologen und heteologen Immunoglobulinen bei neugeborenen Ferkeln
No full textVon den durchschnittlichen Aufzuchtverlusten um 15 % entfällt bei Ferkeln ein Großteil auf die ersten Lebenstage. Dies resultiert u.a. aus einer zu geringen Kolostralmilch- bzw. Immunglobulinaufnahme mit daraus folgender Schwäche und verminderter Abwehrkraft. Ferkel sind auf die Zufuhr von Biestmilch mit ihrem hohen Gehalt an Immunglobulinen angewiesen. Eine Reduktion der neonatalen Sterblichkeit ist somit durch ausreichende Versorgung mit Kolostralmilch zu erreichen, die aufgrund der begrenzten Durchlässigkeit des Darmes innerhalb der ersten Lebensstunden erfolgen muß. Das Ziel der Untersuchung war, einen Beitrag zur Klärung folgende Themen zu liefern: 1. Welchen Einfluß haben Menge und Volumen der Kolostralmilch auf die Absorption der Immunglobuline? 2. Besteht ein Unterschied in der Absorptionsrate zwischen homologen und heterologen Antikörpern? 3. Erfolgt ein selektiver intestinaler Immunglobulin-Transport bei gleichem Angebot von homologem und heterologem Kolostrum? 189 neugeborene Ferkel wurden in 8 Versuchsgruppen mit Schweine- oder Rinderkolostrum unterschiedlicher Portionsgröße und Verdünnung während des ersten Lebenstages versorgt. Gruppe 1 erhielt insgesamt 405 ml/kg Körpergewicht Schweinekolostrum, Gruppe 2 die halbe Menge; dieser Portion wurde in Gruppe 3 Wasser und in Gruppe 4 Rinderkolostrum gleichen Volumens zugesetzt. Bei der analogen Verabreichung von heterologer Kolostralmilch wurde neben Gruppe 5 (Rinderkolostrum), Gruppe 6 (1/2 Menge Rinderkolostrum) und 7 (Rinderkolostrum + Wasser) noch zusätzlich in Gruppe 8 eine Kombination mit Rindermagermilch verfüttert. Durch Berechnung des Absorptionskoeffizienten anhand der Ig-Serumkonzentration zur 18. Stunde, des Körpergewichtes und der aufgenommenen Kolostrummengen je Ferkel war ein objektiver Vergleich der Absorptionskapazität zwischen den Gruppen gewährleistet
Mapping of parent hamiltonians: from abelian and non-abelian quantum hall states to exact models of critical spin chains
No full textThis monograph introduces an exact model for a critical spin chain with arbitrary spin S, which includes the Haldane--Shastry model as the special case S=1/2. While spinons in the Haldane-Shastry model obey abelian half-fermi statistics, the spinons in the general model introduced here obey non-abelian statistics. This manifests itself through topological choices for the fractional momentum spacings. The general model is derived by mapping exact models of quantized Hall states onto spin chains. The book begins with pedagogical review of all the relevant models including the non-abelian statistics in the Pfaffian Hall state, and is understandable to every student with a graduate course in quantum mechanics
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