A path-integral for the t–J model in two dimensions is constructed based on Dirac quantization, with an action found originally by Wiegmann Phys. Rev. Lett. 60 (1988) 821 ; Nucl. Phys. B 323 (1989) ...311. Concentrating on the low doping limit, we assume short range antiferromagnetic order of the spin degrees of freedom. Going over to a local spin quantization axis of the dopant fermions that follows the spin degree of freedom, staggered CP1 fields result and the constraint against double occupancy can be resolved. The staggered CP1 fields are split into slow and fast modes, such that after a gradient expansion, and after integrating out the fast modes and the dopant fermions, a CP1 field-theory with a massive gauge field is obtained that describes generically incommensurate coplanar magnetic structures, as discussed previously in the context of frustrated quantum antiferromagnets.
The analysis of Landau damping shows that in this case, even in the presence of doping, the dynamical critical exponent z=1, as a consequence of coupling of the dopant holes to a spin current, as opposed to a spin density. This result agrees with experimental observations in the underdoped region of high temperature superconductors, and departs from the one obtained by Hertz and Millis (z=2) in the case of spin density waves in the Hubbard model.
We study the ground-state properties of hard-core bosons trapped by arbitrary confining potentials on one-dimensional optical lattices. A recently developed exact approach based on the Jordan-Wigner ...transformation is used. We analyze the large distance behavior of the one-particle density matrix, the momentum distribution function, and the lowest natural orbitals. In addition, the low-density limit in the lattice is studied systematically, and the results obtained compared with the ones known for the hard-core boson gas without the lattice.
A novel organic−inorganic hybrid thermotropic liquid crystal (LC) is developed by the hybridization of an organic phosphate having a mesogenic core and monodispersed α-Fe2O3 particles with different ...shapes through the specific adsorption of the phosphate group to the surfaces parallel to the c-axis of the α-Fe2O3. The hybrid LC shows thermotropic nematic or cubic liquid-crystallinity in wide ranges of temperatures. Variable-temperature small-angle X-ray measurements reveal that the spontaneous formation of periodic structure by the hybridization induces the thermotropic liquid crystallinity. This technique would lead development of novel types of dynamic functional materials with multi-responsiveness to magnetic and electric fields.
Using a newly developed hybrid Monte Carlo algorithm for the nearest-neighbor (nn) t-J model, we show that antiholons identified in the supersymmetric inverse squared (IS) t-J model are clearly ...visible in the electron-addition spectrum of the nn t-J model at J=2t and also for J=0.5t, a value of experimental relevance.
The mole fractions of hydroxo complexes of titanium(IV) ion in an aqueous solution with 0.10 mol dm(-3) NaClO4 at 25 degrees C have been determined as a function of pH by a newly developed analytical ...procedure based on UV spectrophotometry, using a metastable homogeneous solution of 1.25 x 10(-4) mol dm(-30 in total concentration of Ti(IV). Also, the total concentration of the hydroxo complexes in equilibrium with Ti(OH)4 solid, or the solubility of Ti(OH)4 solid in an inhomogeneous system, has been obtained by ICP measurement for the solution phase. A combination of these data yielded the absolute concentration of each complex species in equilibrium with Ti(OH)4 solid. Finally, Ti(OH)+3 complex has been assigned to the precursor for the formation of anatase TiO2 nanoparticles transformed from Ti(OH)4 gel from a comparison between the above equilibrium data and a kinetic study on the formation rate of the anatase TiO2 particles in the gel-sol system.
Background:
The relationship between Helicobacter pylori infection and non‐ulcer dyspepsia is still controversial. The potential benefits and risks of the treatment could depend on local conditions, ...such as the prevalence of the infection and the local rates of gastric cancer.
Aim:
To evaluate the effects of H. pylori eradication therapy on non‐ulcer dyspepsia symptoms in industrial workers in Japan.
Methods:
A total of 615 employees of an industrial corporation were examined for H. pylori infection and symptom scores; 215 H. pylori‐positive non‐ulcer dyspepsia cases underwent eradication therapy. Symptom scores were also analysed 12 months after the eradication therapy. Serum pepsinogen A and pepsinogen C levels were analysed and chronic atrophic gastritis was serologically diagnosed on the basis of the criteria of a pepsinogen A < 70 ng/mL and pepsinogen A : pepsinogen C ratio < 3.0.
Results:
The symptom score improved significantly in the cured cases, but not in the non‐cured cases. The effect of the cure of H. pylori infection on symptoms was analysed according to the serological diagnosis of chronic atrophic gastritis. In both groups, cases with atrophic gastritis and cases with chronic gastritis only, the cure of infection was effective in improving symptoms.
Conclusion:
The cure of H. pylori infection was effective in reducing non‐ulcer dyspepsia symptoms in industrial workers in Japan.
Summary
Background : Effective therapy for gastro‐oesophageal reflux disease (GERD) is associated with improvement in health‐related quality of life. It remains unclear whether Helicobacter pylori ...infection protects against GERD.
Aim : We evaluated the relationship between GERD and H. pylori, and whether the health‐related quality of life score improved after medical treatment.
Methods : We enrolled 151 outpatients with upper abdominal symptoms; 81 patients received omeprazole 20 mg/day for 2 weeks. Health‐related quality of life was assessed using the Gastrointestinal Symptom Rating Scale (GSRS) and the Psychological General Well‐Being (PGWB) index. H. pylori infection was diagnosed by serum antibody or endoscopy and the relationship between GERD and H. pylori was evaluated.
Results : In GERD patients, the mean GSRS score improved from 2.20 to 1.67 following treatment (P < 0.01). The mean GSRS reflux symptom score improved from 2.96 to 1.67 (P < 0.01). The mean PGWB score improved from 96.36 to 107.34 (P < 0.01). All scores in GERD patients significantly improved compared with non‐GERD patients. The H. pylori‐positive ratio was 66.15% in GERD patients and 65.21% in non‐GERD patients (P = 0.94).
Conclusions : Health‐related quality of life is useful for evaluation of proton pump inhibitor treatment in GERD. The presence of H. pylori was not associated with the prevalence of GERD.
Femtosecond optical pulses are generated by an actively modelocked fibre ring laser. The fibre ring cavity includes a dual-electrode Mach-Zehnder optical intensity modulator and an erbium-doped fibre ...amplifier. To generate femtosecond pulses, fast impulse modulation is employed. The modelocking generates femtosecond pulses with a pulse-width of about 500 fs. PUBLICATION ABSTRACT
We report a female patient with systemic lupus erythematous (SLE), hyperbilirubinemia and high serum value of ALT. International autoimmune hepatitis (AIH) score showed definite AIH before treatment, ...but autoantibodies could not make a differential diagnosis of AIH and SLE-associated hepatitis. Liver biopsy showed periportal hepatitis with lymphoplasmacytic infiltration, but neither parenchymal collapse nor rosette formation could be found. Pericarditis, pleuritis and nephritis were improved as well as liver injury after administration of prednisolone, and no repeated attack has been present these 4 years. Our case suggested invalidity of AIH score among patients of SLE, and liver histology should be inferred most important at present to make a differential diagnosis of lupus hepatitis or AIH in patients with SLE.
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