Optical Evidence of Itinerant-Localized Crossover of 4f4f Electrons in Cerium Compounds

Cerium (Ce)-based heavy-fermion materials have a characteristic double-peak structure (mid-IR peak) in the optical conductivity [$\sigma(\omega)$] spectra originating from the strong conduction ($c$)--$f$ electron hybridization. To clarify the behavior of the mid-IR peak at a low $c$-$f$ hybridization strength, we compared the $\sigma(\omega)$ spectra of the isostructural antiferromagnetic and heavy-fermion Ce compounds with the calculated unoccupied density of states and the spectra obtained from the impurity Anderson model. With decreasing $c$-$f$ hybridization intensity, the mid-IR peak shifts to the low-energy side owing to the renormalization of the unoccupied $4f$ state, but suddenly shifts to the high-energy side owing to the $f$-$f$ on-site Coulomb interaction at a slight localized side from the quantum critical point (QCP). This finding gives us information on the change in the electronic structure across QCP.Comment: 6 pages, 4 figures. To appear in JPSJ (Letters

A METHOD OF IMPROVING THE MEASUREMENT OF KINEMATIC PARAMETERS ABOVE AND UNDER WATER IN SWIMMING START

The objectives of this study were to develop an improved method of measuring kinematic parameters of a swimmer at the start of a race from water entry through the initial glide in a seamless manner and to consider deceleration factors with reference to changes in the swimmer’s kinematic parameters during the start. Ten elite collegiate male swimmers participated in this study. To obtain accurate displacements of each reference point on a swimmer while avoiding interference from bubbles, waterproofed, super-luminosity LED markers were used. Additionally, a metallic frame (3 m × 2 m) and a nylon belt (6.1 m long with marks at intervals of 0.5 m) were used as calibration control points. Participants were asked to start from a starting block three times with their maximum effort and maintain a streamlined position without any kicking after water entry until they reached the 10-m point. The mean calibration error was 0.0046 m in the horizontal direction and 0.0047 m in the vertical direction across the measurement span (11 m × 6 m). This improved method enabled us to measure successive changes in the velocity and acceleration of the centre of mass both above water and following water entry

KINETIC ANALYSIS OF START MOTION ON STARTING BLOCK IN COMPETITIVE SWIMMING

The aim of this study was to investigate kinetic features of start motion with use of an instrumented starting block. This is the first study that quantified joint torques of the whole body during start motion. Six male swimmers dived from the instrumented starting block, which contains force plates and sensors. Four high-speed cameras were used to obtain kinematics data of the swimmers. Inverse dynamics calculation was carried out with use of the kinetics and kinematics data. The results showed that 1) the large pulling up forces exerted by both hands were generated by extension toques of the shoulder joints, 2) the rear side lower limb joints exerted large extension torque to obtain horizontal reaction force, and 3) the knee joint of the front side lower limb exerted large flexion torque to maintain the large vertical reaction force until 60% normalized start motion time

Measurements of Total Neutron Cross Sections of C, Fe, Pb, O, Mo, Si, Zn, Ni, Sn, Ti and W at Energies 20-60 MeV

Measurements of total neutron cross sections of C, Fe, Pb, O, Mo, Si, Zn, Ni, Sn, Ti and W were made, using white neutrons from a thick Cu target bombarded by 65- and 75-MeV protons. The cross sections were obtained in the energy range 20-60 MeV. The obtained data agree well with others in the case where other data were already existing. The present work added several new data points for Ni, Mo, Sn, Zn, Ti and W, for which the number of existing data was not enough

Vertical Resolved Dust Mass Concentration and Backscatter Coefficient Retrieval of Asian Dust Plume Using Quartz Raman Channel in Lidar Measurements

In this work, we present a method for estimating vertical resolved mass concentration of dust immersed in Asian dust plume using Raman scattering of quartz (silicon dioxide, silica). During the Asian dust period of March 15, 16, and 21 in 2010, Raman lidar measurements detected the presence of quartz, and successfully showed the vertical profiles of the quartz backscatter coefficient. Since the Raman backscatter coefficient was connected with the Raman backscatter differential cross section and the number density of quartz molecules, the mass concentration of quartz in the atmosphere can be estimated from the quartz backscatter coefficient. The weight percentage from 40 to 70 % for quartz in the Asian dust was estimated from references. The vertical resolved mass concentration of dust was estimated by quartz mass concentration and weight percentage. We also present a retrieval method to obtain dust backscatter coefficient from the mixed Asian dust and pollutant layer. OPAC (Optical Properties of Aerosol and Clouds) simulations were conducted to calculate dust backscatter coefficient. The retrieved dust mass concentration was used as an input parameter for the OPAC calculations. These approaches in the study will be useful for characterizing the quartz dominated in the atmospheric aerosols and estimating vertical resolved mass concentration of dust. It will be especially applicable for optically distinguishing the dust and non-dust aerosols in studies on the mixing state of Asian dust plume. Additionally, the presented method combined with satellite observations is enable qualitative and quantitative monitoring for Asian dust

Variations in the reproductive cycle of Bornean montane tree species along elevational gradients on ultrabasic and non-ultrabasic soils

Although lowland tree species in the ever-wet regions of Southeast Asia are characterized by the supra-annual cycle of reproduction, the reproductive phenology of montane tree species remains poorly understood. In this study, we investigated the reproductive phenology of montane tree species using litter samples that were collected every 2 weeks from six rainforest sites, consisting of three elevations (1700, 2700, and 3100 m), on Mount Kinabalu, Borneo. At each elevation, one site was on infertile ultrabasic soil and one was on relatively fertile non-ultrabasic soil. We used a composite sample from 10 or 20 litter traps per site and sorted it by species. Therefore, the obtained data captured reproductive phenology in the population of each species rather than in an individual tree. Ten-year time series of flower and fruit litterfall were obtained for 30 and 39 tree species, respectively. Fourier analysis was used to identify the dominant cycle of each time series. The most abundant cycle across species was supra-annual, followed by sub-annual, and annual cycles. Many species at higher elevations showed supra-annual cycles of flower litterfall, whereas species in the 1700 m sites often showed annual or sub-annual cycles regardless of soil types. No systematic differences were found among sites for fruit litterfall. Mechanisms underlying these elevational patterns in reproductive cycle remain unclear but may include more severe El Niño droughts, lower primary productivity, lower soil fertility, and the absence of some sub-annually or annually reproducing families at higher elevations

Results of a Screening Program for Multiple Endocrine Neoplasia Type 2A: A Clinical Study of a Japanese Family

A Japanese family of 87 members in five generations with multiple endocrine neoplasia type 2A (MEN 2A) is described regarding the utility of screening tests for early detection of medullary thyroid carcinoma and the potential for DNA diagnosis of MEN 2A gene carriers. The screening programs for family members in this series include measurements of plasma calcitonin concentrations after intravenous injection of pentagastrin (0.5 μg/kg/5 sec) and 24-hour urinary excretion of catecholamines. While 18 MEN 2A patients had been previously diagnosed, these screening programs revealed five additional patients with MEN 2A (aged 16, 19, 35, 37, and 57). Prediction of MEN 2A gene carriers by DNA analysis has been attempted but is not yet possible in this family