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Terahertz (THz) time-domain emission spectroscopy was performed on layered 2H-MoSe 2 and 2H-WSe 2. The THz emission shows an initial cycle attributed to surge currents and is followed by oscillations attributed to coherent interlayer phonon modes. To obtain the frequencies of the interlayer vibrations, an analysis of the THz emission waveforms was performed, separating the two contributions to the total waveform. Results of the fitting show several vibrational modes in the range of 5.87–32.75 cm − 1 for the samples, attributed to infrared-active interlayer shear and breathing modes. This study demonstrates that THz emission spectroscopy provides a means of observing these low-frequency vibrational modes in layered materials.

This study investigates the ultrafast dynamics of coherent phonons and phonon-polaritons in lithium niobate (LiNbO$_{3}$) crystals using reflective pump-probe spectroscopy with 25-fs time resolution. In addition to several coherent optical phonon modes, the electro-optic sampling measurements explored the coexistence of phonon-polariton E-modes near 3.8 and 14.9 THz, which agrees considerably with the theoretical phonon-polariton dispersion curves. We also discovered that a time lag ($\Delta$t $\approx$ 0.2 ps) between the coherent optical phonon and phonon-polariton originates from the coupling time for propagating phonon-polariton. Our findings provide a possible application of LiNbO$_{3}$ for ultrafast electro-optic phonon modulators with bandwidths greater than 10 THz., Comment: 15 pages, 4 figures

Ultrafast dynamics of low-frequency phonon polariton A-mode, longitudinal-optic (LO) modes, transverse-optic (TO) modes, and low and high-frequency E-modes in x-cut lithium niobate crystal have been studied using reflection-type pump-probe spectroscopy with an electro-optic sampling technique.

Antibacterial diospyrodin (1) was synthesized in 13 steps. Et3B and O2 promoted the formation of an α-alkoxy carbon radical from l-ribose-derived α-alkoxyacyl telluride 5, which reacted with d-gluc...

Slaking is a mechanical–hydraulic process in which geomaterials disintegrate or crumble when subjected to wetting and drying cycles; mudstone is particularly susceptible to this process. This paper explores the slaking behaviour of geomaterials derived from several kinds of mudstone and the mechanical consequences using a comprehensive set of experimental data obtained through accelerated slaking tests and newly developed one-dimensional compression slaking tests. These data confirm that slaking in crushed mudstone is accompanied by a variation in the particle size distribution during wetting and drying cycles, and a variation in grading results in an irreversible change in mechanical characteristics, such as the reference packing density. Significant compression is also found to occur without any change in effective confining stress. The results of X-ray fluorescence analysis, X-ray diffraction analysis and scanning electron microscopy are also used to elucidate the effects of mineralogy and particle texture on the slaking characteristics of crushed mudstone. Finally, it is also mentioned that constitutive modelling can take slaking into consideration by describing the evolution of an appropriate grading index due to slaking, and then linking this to reference packing density.

We report on the dynamics of coherent phonons in semimetal 1T′- MoTe 2 using femtosecond pump-probe spectroscopy. On an ultrafast sub-picosecond timescale at room temperature, a low frequency and long-lifetime shear phonon mode was observed at 0.39 THz, which was previously reported in the form of a characteristic phonon only in the low temperature T d − MoTe 2 phase. Unlike the other optical phonon modes, the shear phonon mode was found to strongly couple with photoexcited carriers. Moreover, the amplitude of the shear mode surprisingly decreased with increasing excitation density, a phenomenon that can be attributed to be a consequence of the lattice temperature increasing after excitation. These results provide useful physical information on ultrafast lattice symmetry switching between the normal semimetal 1T′ and the lattice inversion symmetry breaking Type-II Weyl semimetal T d phases.

To develop a simple procedure for estimating glomerular filtration rate (GFR) in calves, a three-sample method using iodixanol was first compared to that using the standard agent inulin. Iodixanol and inulin were co-administered intravenously to calves at 40 mg I/kg and 40 mg/kg, respectively, and blood was collected 30, 60, 120, and 180 min later. Serum iodixanol and inulin concentrations were separately determined by high performance liquid chromatography and colorimetry. Serum urea nitrogen (UN) and creatinine concentrations were also measured. GFR estimated by iodixanol was consistent with that using inulin in clinically healthy calves. Based on GFR estimations in healthy calves and those renal-loaded with iodixanol, it was found that the serum creatinine concentrations became elevated when GFR decreased to 60% of the reference value. In contrast, serum UN concentrations fluctuated widely, presumably due to extra-renal factors. When GFR was estimated using the three-sample method and compared with the single-blood-sample method, 62/69 (90%) of samples tested were within the agreement plots. The results demonstrated that the single-blood-sample method using iodixanol may be useful in monitoring GFR in calves.

Photosymbiotic ascidians inhabiting subtropical waters tend to have gonads in spring and summer, whereas those in tropical waters are usually sexually mature year-round. We studied the seasonality of sexual reproduction in two populations of the photosymbiotic ascidian Didemnum molle (Herdman, 1886), sampling monthly for 12 months. Although the two populations were located only about 20 km apart, their color morphs were exclusively distributed: colonies of one population were always dark gray; those of the other population were mostly brown. The seasonality of sexual reproduction differed greatly between the populations (and thus between the color morphs). Sexual reproduction was limited to summer in the population with dark gray colonies, whereas the population with brown colonies possessed embryos with tails almost year-round. Moreover, the resident crustacean fauna in the colonies also differed between the populations. The microenvironment in each habitat may have caused these differences, but there may also be some physiological differences between the color morphs that affect the seasonality of sexual reproduction and the resident crustacean fauna.

The unmanned aerial vehicles (UAVs) are the aircraft without a human operator on board. Since operators can control the aircraft without some danger, they are useful as an emergency aerial observation method. In this paper, as one of these UAVs, we focus on the flying wing which is a fixed-wing aircraft. In general, the fixed-wing-type UAV can fly longer time than the helicopter-type one because the lift force is produced by rotation of propeller only. However, since the flying speed is very fast in order to produce lift force, it is difficult to take the stationary picture for the observation. Therefore, we have developed the flying wing which can fly slowly at a small field. Moreover, in order to realize the autonomous flight, we have proposed a target point follow-up control method. Then, the effectiveness of the proposed flying wing is explained by experimental results.

An unmanned flying boat is an aircraft which is designed to take off and land on water. The unmanned flying boat is useful as an emergency aerial observation method. In previous researches, we have developed the small flying boat controlled by the human operator. In this paper, we consider automatic control for the flying boat. However, since the flying boat is used the gyro sensor, the sensor offset may occur by that surrounding humidity and temperature changes, aging, external vibrations, mechanical stress, and so on. The sensor offset produces non-zero steady-state input and output signals, even if the flying boat is stabilized. In previous research, it has been investigated that steady-state blocking zeros of the stabilizing controller play an important role. Such a controller is called a washout controller. In this paper, we apply the washout controller to the stabilization for the flying boat with the sensor offset. Then, we show that the washout controller eliminates the bias in the steady-state and stabilizes the flying boat. Moreover, we show some simulation results which illustrate the effectiveness of the proposed control method.

Birefringence imaging microscopy is well suited for comprehensively investigating various structural phase transitions but its weak point is that it imposes an inherent limit on the maximum retardance that can be detected. To detect retardance above this limit, we performed simultaneous birefringence measurements at multiple wavelengths on (CnH2n+1NH3)2MnCl4 with \(n = 1,2,3\). For n = 1, we successfully detected large jumps in retardance (over six times greater than the limit) in the first-order phase transitions at Tc1 \( \simeq \) 88 K and Tc2 \( \simeq \) 251 K. For n = 2, a gradual change in retardance appears in the second-order phase transition at Tc = 214 K. High-definition images of optical fast-axis azimuths provided information on the misorientation of the alkylammonium chains. For n = 3, a retardance kink appears at Tc4 \( \simeq \) 152–155 K, and a retardance jump appears in the commensurate-incommensurate phase transition at Tc5 \( \simeq \) 96–99 K.

One of the next-generation reactors, SBWR (simplified boiling water reactor), is currently under development. It has a large upper plenum surrounded by the so-called "chimney" to keep a driving force of natural circulation. An accurate method for predicting bubble-induced natural circulation is therefore indispensable for the rational design of SBWR. In the present study, the applicability of the multidimensional two-fluid model to bubble-induced transient natural circulation was examined by comparing measured transient flow patterns with calculated ones. The calculation was conducted by coupling a two-dimensional incompressible two-fluid model with available constitutive equations for interfacial drag force, lift force, virtual mass force and viscous force. The 3rd-order new-class TVD scheme was adopted for the convection term of the mass equations to reduce the numerical diffusion of volumetric fractions. As the result, we could obtain good predictions for transient flow patterns. It was also confirmed that the large-scale turbulent flow field induced by the bubble plume can be predicted well without any turbulence model.

To evaluate the relationship between difficulty in daily living and binocular visual field in patients with glaucoma.We examined 144 patients with glaucoma who had bilateral visual field disturbances. The mean age was 68 +/- 13 years. Difficulty in daily living was assessed using a questionnaire consisting of 10 questions on daily activities. Each response was rated on a scale of 1 to 4: with a score of 4 for "no difficulty", 3 for "some difficulty", 2 for "great difficulty" and 1 for "cannot manage at all". The binocular visual field was assessed using the Esterman visual field test and the Esterman score was calculated. The relationship between difficulty in daily living and Esterman score was evaluated.The mean total score for difficulty in daily living was 34 +/- 7 (range; 13-40). The mean Esterman score was 79 +/- 24 (range; 0-100). The total score for difficulty in daily living correlates positively with the Esterman score (r2 = 0.48, p0.0001).The present study indicates that the Esterman score is a good predictor of difficulty daily living.

We investigated the correlation of age and intraocular pressure (IOP) with visual field damage in patients with normal-tension glaucoma (NTG) and asymmetric visual field defects.A total of 88 NTG patients (176 eyes) were investigated. Patients in whom visual field defects were more severe in the eye with higher IOP than in the fellow eye were grouped as IOP-visual field-concordant patients, and the others as IOP-visual field-discordant patients. Mean 24-hour IOP was used as an indicator of IOP, and mean deviation (MD) as an indicator of visual field defects. Patients were also compared by age tertile.The IOP-visual field-concordant group comprised 53 of the 88 patients (60.2%), among whom the70-years tertile had significantly greater absolute values for MD asymmetry. In contrast, no significant differences in asymmetry by age tertile were seen in the IOP-visual field-discordant group.Elevated IOP is a cause of visual field defects in many NTG patients. Among IOP-visual field-concordant patients, particular attention is required to visual field changes in the eyes of patients with higher IOP.

Morphological processes in the vertical transmission of photosymbionts were investigated in the Prochloron-bearing ascidian Didemnum molle. Prochloron cells were found exclusively in the common cloacal cavity of the colony, attached mainly to the tunic lining of the cavity wall. Oocytes were found in the abdominal region of each zooid, but no Prochloron cells were associated with this stage. During embryogenesis, embryos moved into the tunic core of the colony and were always separated from Prochloron cells in the cloacal cavity by the tunic matrix, until they hatched out from the tunic core. In swimming larvae, Prochloron cells covered the surface of the posterior half of the larval trunk, whereas a thin larval tunic layer covered the anterior half, where no Prochloron cells were found. The tunic of the posterior half of the larval trunk had many folds that enfolded the Prochloron cells and may be adhesive in order to acquire Prochloron cells from the mother colony. The thin larval tunic layer is probably not adhesive and protects the anterior half of the trunk from interference by Prochloron cells with sensory receptors and adhesive organs.

To compare the effects of latanoprost (Lat) and timolol gel-forming solution (Tg) on the diurnal variation of intraocular pressure (IOP) in normal-tension glaucoma (NTG).A total of 47 NTG patients (47 eyes) were randomly assigned to receive Lat alone (25 eyes) or Tg alone (22 eyes). IOP was measured at fixed time points during 24 hours before and after treatment with each drug. In addition, blood pressure and pulse rate were measured before and after treatment.Lat reduced IOP significantly at all time points of measurement. Tg reduced IOP significantly at all time points of measurement except at 22:00 and 03:00. Percent reductions in the IOP at 03:00 and in the mean diurnal IOP were significantly greater in the Lat group than in the Tg group. In the Lat group there was no change in diastolic pressure or pulse rate after treatment, but in the Tg group these parameters decreased significantly.Comparison of diurnal variation of IOP before and after treatment shows that Lat is more effective than Tg in lowering IOP. In addition, Lat does not affect blood pressure or pulse rate.

精子の凍結保存は種々の魚種で可能になっているが, 小型魚については報告例は極めて少ない。全長約5cmのタイリクバラタナゴから精巣を取り出し, 凍結保護物質としてDMSOを含む希釈液中に入れ, はさみで刻み穏やかに撹拌した後, ゆっくりとした温度降下で凍結し, 液体窒素中で保存した。2日後および30日後に解凍し媒精を行ったところ, 受精卵が得られた。採精量の少ない小型魚では, 精巣内精子を用いることが精子の凍結保存の有効な一手法と成り得ることが示唆された。

To study the effect of instillation of latanoprost on the diurnal variation in the intraocular pressure(IOP), blood pressure, and pulse rate in patients with normal-tension glaucoma(NTG).The diurnal variation in the IOP was determined in 23 eyes in 23 NTG patients after a washout period of 4 weeks or longer. The diurnal variation in IOP was then remeasured after latanoprost monotherapy of 8 weeks or longer. The IOP was measured by the Goldmann applanation tonometer at 10:00, 13:00, 16:00, 19:00, 22:00, 01:00, 03:00, 07:00, and 10:00 before and after treatment, and the IOP at each time point, mean diurnal IOP, maximum IOP, minimum IOP, and range of variation in IOP were compared before and after treatment. The blood pressure and pulse rate before and after treatment were also measured and compared.The IOP decreased significantly at all time points. The treatment caused significant decreases in the mean diurnal IOP, maximum IOP, minimum IOP, and range of variation in IOP. There were no differences in the blood pressure and pulse rate before and after treatment.Latanoprost significantly decreases the IOP throughout the day in NTG patients, and has no effects on the blood pressure and pulse rate. It is therefore useful in the treatment of NTG.

SiO 2 -GeO 2 glasses have been prepared by the sol-gel method, and Raman scattering, fluorescence and refractive indices have been measured. Very broad fluorescence bands due to Ge ions are observed around 530 nm. The fluorescence intensity depends on the water content of glass. Samples heated to 800 ° C have no fluorescence band in this region. We discuss the origin of this fluorescence center as due to the defect structure of the dangling bond between Ge and O ions.