723 research outputs found
Improved efficiency of selective photoionization of palladium isotopes via autoionizing Rydberg states
Circular resonant cavities as basis of random lasing in Ïâ conjugated polymer films
Superconductivity induced by doping Platinum in BaFe2As2
By substituting Fe with the 5d-transition metal Pt in BaFe2As2, we have
successfully synthesized the superconductors BaFe2-xPtxAs2. The systematic
evolution of the lattice constants indicates that the Fe ions were successfully
replaced by Pt ions. By increasing the doping content of Pt, the
antiferromagnetic order and structural transition of the parent phase is
suppressed and superconductivity emerges at a doping level of about x = 0.02.
At a doping level of x = 0.1, we get a maximum transition temperature Tc of
about 25 K. The synchrotron powder x-ray diffraction shows that the resistivity
anomaly is in good agreement with the structural transition. The
superconducting transitions at different magnetic fields were also measured at
the doping level of about x = 0.1, yielding a slope of -dHc2/dT = 5.4 T/K near
Tc. A phase diagram was established for the Pt doped 122 system. Our results
suggest that superconductivity can also be easily induced in the FeAs family by
substituting the Fe with Pt, with almost the similar maximum transition
temperatures as doping Ni, Co, Rh and Ir.Comment: 6 pages, 5 figure
Quasi-Solitons in Dissipative Systems and Exactly Solvable Lattice Models
A system of first-order differential-difference equations with time lag
describes the formation of density waves, called as quasi-solitons for
dissipative systems in this paper. For co-moving density waves, the system
reduces to some exactly solvable lattice models. We construct a shock-wave
solution as well as one-quasi-soliton solution, and argue that there are
pseudo-conserved quantities which characterize the formation of the co-moving
waves. The simplest non-trivial one is given to discuss the presence of a
cascade phenomena in relaxation process toward the pattern formation.Comment: REVTeX, 4 pages, 1 figur
Cosmic shear statistics in the Suprime-Cam 2.1 sq deg field: Constraints on Omega_m and sigma_8
We present measurements of the cosmic shear correlation in the shapes of
galaxies in the Suprime-Cam 2.1 deg^2 R_c-band imaging data. As an estimator of
the shear correlation originated from the gravitational lensing, we adopt the
aperture mass variance. We detect a non-zero E mode variance on scales between
2 and 40arcmin. We also detect a small but non-zero B mode variance on scales
larger than 5arcmin. We compare the measured E mode variance to the model
predictions in CDM cosmologies using maximum likelihood analysis. A
four-dimensional space is explored, which examines sigma_8, Omega_m, Gamma and
zs (a mean redshift of galaxies). We include three possible sources of error:
statistical noise, the cosmic variance estimated using numerical experiments,
and a residual systematic effect estimated from the B mode variance. We derive
joint constraints on two parameters by marginalizing over the two remaining
parameters. We obtain an upper limit of Gamma0.9 (68% confidence).
For a prior Gamma\in[0.1,0.4] and zs\in[0.6,1.4], we find
sigma_8=(0.50_{-0.16}^{+0.35})Omega_m^{-0.37} for flat cosmologies and
sigma_8=(0.51_{-0.16}^{+0.29})Omega_m^{-0.34}$ for open cosmologies (95%
confidence). If we take the currently popular LCDM model, we obtain a
one-dimensional confidence interval on sigma_8 for the 95.4% level,
0.62<\sigma_8<1.32 for zs\in[0.6,1.4]. Information on the redshift distribution
of galaxies is key to obtaining a correct cosmological constraint. An
independent constraint on Gamma from other observations is useful to tighten
the constraint.Comment: 12 pages, 12 figures, accepted for publication in Ap
Lipid profile disturbances are highly prevalent in Japanese-Brazilians
Alta prevalĂȘncia de diabetes em população nipo-brasileira de Bauru/SP foi previamente relatada. Visando a complementar a avaliação do risco cardiometabĂłlico, este estudo analisou distĂșrbios no perfil lipĂdico de 1.330 nipo-brasileiros (46% homens) > 30 anos. Definiu-se hipercolesterolemia por nĂveis de colesterol total > 240 mg/dL; hipertrigliceridemia por valores > 150 mg/dL e HDL-colesterol baixo por valores < 40 mg/dL e < 50 mg/dL para homens e mulheres, respectivamente. A prevalĂȘncia desses distĂșrbios foi comparada pelo qui-quadrado, estratificando-se por sexos e categorias glicĂȘmicas. As mĂ©dias dos lipĂdeos e lipoproteĂnas foram comparadas entre sexos pelo teste t de Student. A prevalĂȘncia de hipertrigliceridemia foi de 66,0% (IC95%:63,5 - 68,5%), sendo mais comum em homens e aumentando com a piora da categoria glicĂȘmica; a trigliceridemia mĂ©dia foi 235,7 ± 196,3 mg/dL. A prevalĂȘncia de hipercolesterolemia foi 24,4% (IC95%:22,1 - 26,7%); HDL-C baixo foi observado em 43,0% (IC95%:39,4 - 46,6%] das mulheres e 17,5% (IC95%:14,5 - 20,5%) dos homens, porĂ©m a razĂŁo colesterol total/HDL-C foi menor em mulheres (4,23 ± 0,68 vs. 4,40 ± 0,73; p < 0,001). Em nipo-brasileiros, a hipertrigliceridemia Ă© a anormalidade lipĂdica mais comum, em concordĂąncia com a elevada prevalĂȘncia de diabetes. Os homens apresentaram pior perfil lipĂdico que as mulheres. Sugere-se que hĂĄbitos de vida ocidental possam estar deteriorando a saĂșde desses indivĂduos.High prevalence of diabetes has been previously reported in Japanese-Brazilians. In an attempt to better estimate the cardiometabolic risk, this study evaluated lipid disorders in 1,330 Japanese-Brazilians (46% men) aged >30 years. Hypercholesterolemia was defined as serum cholesterol > 240 mg/dL, hypertriglyceridemia as values > 150 mg/dL and low-HDL-C as values <40 mg/dL and <50 mg/dl for men and women respectively. The prevalence of dyslipidemias was compared by the chi-square test between gender and glycemic category. Mean and Standard Deviation of lipids and lipoproteins were compared by the Student t-Test between gender. Hypertriglyceridemia was detected in 66.0% [95% CI: 63.5-68.5] of the population, being more common in men and increasing with deterioration of glucose metabolism. Mean level of triglycerides was 235.7±196.3 mg/dL. The prevalence of hypercholesterolemia was 24.4% [95% CI: 22.1- 26.7]. Low HDL-C was observed in 17.5% [95% CI: 14.5-20.5] of men and 43.0% [95% CI: 39.4- 46.6] of women but total / HDL-cholesterol ratio was lower in women (4.23 ± 0.68 vs. 4.40 ± 0.73, p<0.001). In Japanese-Brazilians, hypertriglyceridemia is the commonest dyslipidemia, in agreement with the high prevalence of diabetes. Men showed a worse lipid profile than women; it was suggested that the Western diet and living habits could be deteriorating their health.Fundação de Amparo Ă Pesquisa do Estado de SĂŁo Paulo (FAPESP
Analysis of Patients Visiting Niigata University Medical and Dental Hospital with Chief Complaints of Metal Allergy And/or Focal Infection in the Previous 8 Years
Dental metal allergy and dental focal infection are possible causes of dermatological diseases, but have been the subjects of few reports to date. We have been treating such patients in our special clinic for more than 20 years.The purpose of the present study was to investigate the mouths of patients visiting our dental hospital over an 8-year period, with the aim of clarifying whether dental metal allergy and/or dental focal infection affects their dermatologic conditions.We surveyed all clinical records of the 185 patients who visited Niigata University Medical and Dental Hospital with chief complaints of dental metal allergy since 2002. Diagnostics of skin diseases, periodontal records, periapical lesions, dental caries, dental metal series patch test results and Electron Probed Micro-Analysis (EPMA) data were investigated. Ninety-two (49%) patients were suffering from pustulosis palmaris et plantaris and 20 (11%) patients had lichen planus. Eighty-two (49%) patients showed positive reactions on patch testing. Based on the result of patch tests, Ni showed the highest positivity rate (62%, 51 patients), but on EPMA, the number of patients with Ni as an allergen was 14 (27%). On the other hand, more than 98% of patients who showed positive reactions on patch test to Pd and Au had these metals in their dental prostheses. In addition, 112 (60%) patients showed the possibility of dental focal infection
Crystalline ground state in chiral Gross-Neveu and Cooper pair models at finite densities
We study the possibility of spatially non-uniform ground state in
(1+1)-dimensional models with quartic fermi interactions at finite fermion
densities by introducing chemical potential \mu. We examine the chiral
Gross-Neveu model and the Cooper pair model as toy models of the chiral
symmetry breaking and the difermion pair condensates which are presumed to
exist in QCD. We confirm in the chiral Gross-Neveu model that the ground state
has a crystalline structure in which the chiral condensate oscillates in space
with wave number 2\mu. Whereas in the Cooper pair model we find that the vacuum
structure is spatially uniform. Some discussions are given to explain this
difference.Comment: 18 pages, REVTeX, 3 eps figure
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