299 research outputs found

    Hofstadter butterflies for flat bands

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    Hofstadter's diagram, or the energy spectrum against the magnetic field in tight-binding systems, is obtained for the models having flat (dispersionless) one-electron band(s) that have originally been proposed for itinerant spin ferromagnetism. Magnetic fields preserve those flat bands that arise from a topological reason, while dispersions emerge in a singular manner for the flat bands arising from interference, implying an anomalous orbital magnetism.Comment: 9 pages, revtex, 4 figures available on request from [email protected]

    A Case of Pleuroperitoneal Communication in Continuous Ambulatory Peritoneal Dialysis

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    We present a patient who developed a massive right-Sided hydrothorax two months after starting CAPD treatment, a 41-year-old female with IgA nephropathy who was followed up at our outpatient clinic. Due to deteriorating renal function, a peritoneal catheter was inserted on March 29, 1997.CAPD was implemented on the same day. At the time when CAPD was initiated, the patient was experienclng repeated episodes of nausea and vomiting, probably due to uremia. On May 27, she developed dyspnea. A chest X-ray Showed massive right-Sided hydrothorax. After extracorporeal ultrafiltration was performed, the patient's respiratory distress was rapidly relieved. Two days later, CAPD was esumed, but this resulted in almost immediate recurrence of massive right-sided hydrothorax. The property of the drained fluid from the right pleural cavity and scintigraphy uslng Technetium-99m macroaggregated albumin confirmed pleuroperitoneal communication. Increased intra-abdominal pressure due to frequent vomiting may be responsible for hydrothorax due to pleuroperitoneal communication

    Current bonding systems for resin-bonded restorations and fixed partial dentures made of silver–palladium–copper–gold alloy

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    SummaryThis review article describes about the bonding systems for noble metal alloys, bonding techniques of restorations and fixed partial dentures (FPDs) made of Ag–Pd–Cu–Au alloys, and their clinical performance. Thione monomers, 6-(4-vinylbenzyl-n-propyl) amino-1,3,5-triazine-2,4-dithione (VTD), 6-methacryloyloxyhexyl-2-thiouracil-5-carboxylate (MTU-6), and 10-methacryloxydecyl 6,8-dithiooctanoate (MDDT), has been proved effective for bonding noble metal alloys. An acrylic adhesive consists of the tri-n-butylborane (TBB) initiator, methyl methacrylate (MMA) monomer liquid with 5% 4-methacryloyloxyethyl trimellitate anhydride (4-META), and poly(methyl methacrylate) (PMMA), is being used for bonding metallic restorations to abutment surfaces. Clinical performance of restorations and FPDs made of Ag–Pd–Cu–Au alloys is overall excellent when they are seated with the currently available noble metal bonding systems

    Analysis of RAPD and AFLP markers linked to resistance to Fusarium oxysporum f. sp lactucae race 2 in lettuce (Lactuca sativa L.)

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    Root rot of lettuce, which is caused by Fusarium oxysporum f. sp. lactucae (FOL), is a critical problem in the production of lettuce. FOL-resistant lettuce genetic resources have been identified and used in breeding programs to produce FOL-resistant cultivars. However, the genetic characteristics of resistance genes have not been studied in depth and, therefore, no DNA markers are presently available for these genes. In this study, we analyzed the RRD2 (resistance for root rot disease race 2) locus, which confers resistance to FOL race 2. Resistance loci were analyzed using two cultivars of crisphead lettuce: VP1013 (resistant) and Patriot (susceptible). The segregation patterns of resistant phenotypes in F-2 indicated a single major locus. To define the positions of resistance loci, a linkage map was constructed using amplified fragment length polymorphism and random amplified polymorphic DNA (RAPD) markers. Quantitative trait loci analysis revealed the position of the major resistance locus. A high LOD score was observed for RAPD-marker WF25-42, and this marker showed good correspondence to the phenotype in different cultivars and lines. We successfully developed a sequence characterized amplified region marker from WF25-42.ArticleEUPHYTICA. 187(1):1-9 (2012)journal articl

    Molecular characterization of the CRa gene conferring clubroot resistance in Brassica rapa

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    Clubroot disease is one of the major diseases affecting Brassicaceae crops, and a number of these crops grown commercially, such as Chinese cabbage (Brassica rapa L. ssp. pekinensis), are known to be highly susceptible to clubroot disease. To provide protection from this disease, plant breeders have introduced genes for resistance to clubroot from the European turnip into susceptible lines. The CRa gene confers specific resistance to the clubroot pathogen Plasmodiophora brassicae isolate M85. Fine mapping of the CRa locus using synteny to the Arabidopsis thaliana genome and partial genome sequences of B. rapa revealed a candidate gene encoding a TIR-NBS-LRR protein. Several structural differences in this candidate gene were found between susceptible and resistant lines, and CRa expression was observed only in the resistant line. Four mutant lines lacking clubroot resistance were obtained by the UV irradiation of pollen from a resistant line, and all of these mutant lines carried independent mutations in the candidate TIR-NBS-LRR gene. This genetic and molecular evidence strongly suggests that the identified gene is CRa. This is the first report on the molecular characterization of a clubroot Resistance gene in Brassicaceae and of the disease resistance gene in B. rapa.ArticlePLANT MOLECULAR BIOLOGY. 80(6):621-629 (2012)journal articl
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