Relaxing Constraints on Inflation Models with Curvaton

We consider the effects of the curvaton, late-decaying scalar condensation, to observational constraints on inflation models. From current observations of cosmic density fluctuations, severe constraints on some class of inflation models are obtained, in particular, on the chaotic inflation with higher-power monomials, the natural inflation, and the new inflation. We study how the curvaton scenario changes (and relaxes) the constraints on these models.Comment: 18 pages, 6 figure

Quantum Critical Point of Itinerant Antiferromagnet in Heavy Fermion

A quantum critical point (QCP) of the heavy fermion Ce(Ru_{1-x}Rh_x)_2Si_2 (x = 0, 0.03) has been studied by single-crystalline neutron scattering. By accurately measuring the dynamical susceptibility at the antiferromagnetic wave vector k_3 = 0.35 c^*, we have shown that the energy width Gamma(k_3), i.e., inverse correlation time, depends on temperature as Gamma(k_3) = c_1 + c_2 T^{3/2 +- 0.1}, where c_1 and c_2 are x dependent constants, in a low temperature range. This critical exponent 3/2 +- 0.1 proves that the QCP is controlled by that of the itinerant antiferromagnet.Comment: 4 pages, 3 figure

Vertical Changes of Recent Ostracode Assemblages and Environment in the Inner Part of Jakarta Bay, Indonesia

A short sediment core from the inner part of Jakarta Bay, Indonesia, was quantitatively analysed for ostracods (minute Crustacea), total organic carbon (TOC) and total nitrogen (TN) contents, and the vertical distributions were recorded. A total of 53 ostracod species were obtained from 80 continuous core samples. The dominant species were Keijella carriei and Loxoconcha wrighti, which are common in areas with high TOC and TN contents. Based on an analysis of ostracod assemblages and carbon/nitrogen ratio, the study site began to be influenced by organic contamination from around 1950. Although the population of Jakarta City has increased rapidly since then, TOC and TN contents which were low, have gradually increased (0.7%–0.9% and 0.10%–0.12%, respectively), probably due to addition of nutrients from river sedimentation. The increased sedimentation rate after 1950 resulted in an increasing TOC ratio. The observed correlation between TOC and dominant species shows that Phlyctenophora orientalis may be a good indicator for monitoring increases in the narrow TOC content range of 0.7%–1.1%

Intrahepatic Cholangiocarcinoma with Sarcomatous Changes

A 61-year-old Japanese male was seen at an outside hospital with abdominal pain and distention. An intraabdominal mass was found on abdominal computed tomography (CT), and he was referred for further evaluation. He was afebrile, with mild tenderness in the upper abdomen and massive distention. Routine blood work showed severe inflammation and anemia. Repeat CT showed a large solitary heterogeneous mass, 25 cm in diameter, in the left upper quadrant with evidence of intratumoral bleeding and irregular enhancement peripherally. There was no clear distinction between the mass and the peripheral organs. Surgery was performed with persistent anemia and exacerbation of abdominal pain. Lateral segmentectomy, total gastrectomy, cholecystectomy and partial resection of the diaphragm and parietal peritoneum were performed. The final diagnosis was cholangiocarcinoma with sarcomatous changes. On the 16th postoperative day a CT scan revealed recurrent tumor. The patient died on the 34th postoperative day from rapid tumor progression

Coherent Acoustic Perturbation of Second-Harmonic-Generation in NiO

We investigate the structural and magnetic origins of the unusual ultrafast second-harmonicgeneration (SHG) response of femtosecond-laser-excited nickel oxide (NiO) previously attributed to oscillatory reorientation dynamics of the magnetic structure induced by d-d excitations. Using time-resolved x-ray diffraction from the (3/2 3/2 3/2) magnetic planes, we show that changes in the magnitude of the magnetic structure factor following ultrafast optical excitation are limited to $\Delta/$ = 1.5% in the first 30 ps. An extended investigation of the ultrafast SHG response reveals a strong dependence on wavelength as well as characteristic echoes, both of which give evidence for an acoustic origin of the dynamics. We therefore propose an alternative mechanism for the SHG response based on perturbations of the nonlinear susceptibility via optically induced strain in a spatially confined medium. In this model, the two observed oscillation periods can be understood as the times required for an acoustic strain wave to traverse one coherence length of the SHG process in either the collinear or anti-collinear geometries.Comment: 26 pages, 7 figure

Comparisons of various CFD models for computing river flows focusing on secondary currents

River hydrodynamicsTurbulent open channel flow and transport phenomen

Predicting rectal cancer T stage using circumferential tumor extent determined by computed tomography colonography

SummaryBackground and aimPatients with stage T3 or T4 rectal cancer are candidates for neoadjuvant chemoradiation therapy. The aim of this study is to clarify the usefulness of circumferential tumor extent determined by computed tomography (CT) colonography in differentiating T3 or T4 from T1 or T2 rectal cancer.MethodsSeventy consecutive rectal cancer patients who underwent curative-intent surgery were enrolled in this study. All patients underwent colonoscopy and CT colonography on the same day. The circumferential tumor extent was estimated in 10% increments. The pathological T stage was used as the reference.ResultsThe median circumferential tumor extent evaluated by colonoscopy for T1 (n = 6), T2 (n = 21), and T3/T4 (n = 43) were 10%, 30%, and 80%, respectively (T1/T2 vs. T3/T4, p < 0.0001). The median circumferential tumor extent evaluated by CT colonography for T1, T2, and T3/T4 is 10%, 30%, and 70%, respectively (T1/T2 vs. T3/T4, p < 0.0001). The correlation coefficient between colonoscopy and CT colonography was very high (0.94). By defining a circumferential tumor extent ≥50% by CT colonography as the criterion for stage T3 or T4, the sensitivity, specificity, positive predictive value and accuracy were 72%, 88%, 91%, and 79%, respectively.ConclusionCircumferential tumor extent ≥50% determined by CT colonography is a simple and potentially useful marker to identify candidates for neoadjuvant chemoradiation therapy

Suppression of atomic displacive excitation in photo-induced A1g_{\mathrm{1g}} phonon mode of bismuth

Atomic motion of a photo-induced coherent phonon of bismuth (Bi) is directly observed with time-resolved x-ray diffraction under a cryogenic temperature. It is found that displacive excitation in a fully symmetric A$_{\mathrm{1g}}$ phonon mode is suppressed at a temperature $T = 9$ K. This result implies a transfer of the phonon-generation mechanism from displacive to impulsive excitation with decreasing the temperature. It is comprehensively understandable in a framework of stimulated Raman scattering. The suppression of displacive excitation also indicates that the adiabatic potential surface at the photo-excited state deviates from a parabolic one, which is assumed to be realized at room temperature. This study points out important aspects of phonon generation in transient phonon-induced quantum phenomena

Spin-density wave versus superconducting fluctuations for quasi-one-dimensional electrons in two chains of Tomonaga-Luttinger liquids

We study possible states at low temperatures by applying the renormalization-group method to two chains of Tomonaga-Luttinger liquids with both repulsive intrachain interactions and interchain hopping. As the energy decreases below the hopping energy, three distinct regions I, III, and II appear successively depending on properties of fluctuations. The crossover from the spin-density wave (SDW) state to superconducting (SC) state takes place in region III where there are the excitation gaps of transverse charge and spin fluctuations. The competition between SDW and SC states in region III is crucial to understanding the phase diagram in the quasi-one-dimensional organic conductors.Comment: 11 pages, Revtex format, 1 figure, to be published in Phys. Rev.