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Nuclear magnetic resonance under high pressure (3.0 GPa at room temperatures) were performed in a spin ladder system, Sr 2 Ca 12 Cu 24 O 41 where the superconductivity is realized by applying pressure above 3 GPa at low temperatures. The relaxation rate 1/ T 1 on 63 Cu nuclei shows an activated behavior at high temperatures above 50 K although the system is metallic, and the value of the excitation gap is almost the same with that at ambient pressure. The fact implies breakdown of a scenario that pressure vanishes the spin gap and then superconductivity is induced.

A 1.3 µm, 50 Gbit/s electroabsorption modulator integrated with a DFB laser for future parallel LAN, the total data rate of which is over 100 Gbit/s, is developed. Very clear eye openings after 40 km transmission under 50 Gbit/s operation on singlemode fibre are demonstrated for eight wavelengths with discrete packages for the first time.

A 64-year-old man was admitted to hospital under the suspicion of unstable angina pectoris. Coronary angiography showed that he has a single coronary artery originating from the right coronary artery (RCA) without significant fixed stenosis. Acetylcholine was superselectively infused into the left main coronary artery (LMCA), and confirmed the coronary vasospastic occlusion associated with chest pain and elevation of the ST-segment in the precordial leads. This is the first report of the induction of a totally occlusive spasm of the LMCA of a patient with a RCA type single coronary artery, and this case suggests that spasm of the aberrant coronary artery is a potential mechanism for sudden death in patients with a single coronary artery.

We fabricated a small Bridgeman anvil cell with a barrel-like shape for measurements under high-pressure up to 8 GPa. A Teflon cell with an inner volume of 1.5 mm in diameter and 2 mm in length is inserted in the pyrophyllite gaskets and is fixed between upper and lower tungsten-carbide (WC) anvils. The anvils are fastened by a Cu-Be holder with an outer diameter of 40 mm and 43 mm in length. Both of the top and bottom edges of the holder are tapered. This barrel-like shape enables rotation in a superconducting magnet with an inner diameter of 54 mm. The pressure is calibrated by measuring the resistivity of Bi at room temperature. The resistivity of Bi changed under loads at 8.0, 8.45, and 14.7 tons, corresponding to the structural phase transitions.

Nuclear magnetic resonance (NMR) on an iron (Fe)-based superconductor LaFeAsO1-xFx (x = 0.08 and 0.14) was performed at ambient pressure and under pressure. The relaxation rate 1/T1 for x = 0.14 shows T-linear behavior just above Tc, and pressure application enhances 1/T1T similar to Tc. This fact implies that 1/T1T = constant originates from Korringa relation and an increase in the density of state at the Fermi energy D(EF) leads to the enhancement of Tc. In the case of x = 0.08, 1/T1 measured at ambient pressure also shows T-linear behavior in a wide temperature range above Tc. The value of 1/T1T is enhanced compared to the x = 0.14 doped sample, although their Tc values are in the same range. The enhancement of 1/T1T for x = 0.08 is attributable to antiferromagnetic fluctuation rather than an increase in D(EF).

51V nuclear-magnetic-resonance (NMR) measurements were performed on β-Ag0.33V2O5, a quasi-one-dimensional conductor with three crystallographically inequivalent V sites (V1, V2, and V3). We observed the site difference between the V1 and V2 sites. The nuclear quadrupole frequency (νQ) shows different temperature dependence between the V1 and V2 sites, and the values of the relaxation rate (1/T1) are also different between the two sites in the metallic phase. These facts suggest that a non-uniform metallic state is realized: a 3d electron shared within a V1–V3 or V2–V2 rung in the CO phase could move in the quasi-one-dimensional direction in the metallic phase.

A study of 59 Co -NMR on single crystals of LaCoO3 is presented in order to investigate the spin-state transition through the nuclear-spin relaxation. The spin–lattice and spin–spin relaxation rates exhibit a thermal activation-type temperature dependence at low temperatures, suggesting the spin-singlet ground state with a spin gap. The magnitude of the gap energy ∼180 K is close to the values predicted by the two-stage spin-state model including the intermediate spin state, supporting the propriety of the model.

Nuclear magnetic resonance (NMR) on Cu nuclei was performed precisely at low temperatures for a 2% Zn-doped sample to investigate the critical behavior near the ordering point. The NMR spectra broaden as temperature is decreased toward the ordering point. The intensity of the NMR peak attains a minimum at 7 K and then increases at low temperatures below the ordering point. The behavior is in good agreement with the result of the susceptibility.

75As-nuclear magnetic resonance (NMR) on an iron-based superconductor LaFeAsO1-xFx (x=0.14) was performed under a pressure of 3GPa. Enhancement of superconducting transition temperature Tc was confirmed from the relaxation rate 1/T1; Tc goes up to 40K by applying pressure up to 3GPa. 1/T1T, which is temperature independent just above Tc and gives a measure of the density of states (DOS) at the Fermi energy, enhances by applying pressure. These facts suggest that the increase of the DOS leads to the enhancement of Tc. On the other hand, anomalous behavior of 1/T1T observed at high temperatures is suppressed by applying pressure., Comment: 4pages, 5figures. Scheduled to appear in Journal of Phys. Soc. Jpn VoL.78 No.2 (2009)

A high-performance 1.3 μm InGaAlAs electroabsorption modulator integrated with a DFB laser for the metro-area 100 Gbit/s Ethernet system (100GBASE-LR4 and -ER4) has been developed. 40 km transmission under 25 Gbit/s operation on singlemode fibre that is required for 100GBASE-ER4 application at 40°C is demonstrated for the first time.

As a part of our comparative morphological study of mechanoreceptors in rodent oral mucosae, the hard palate of the mongolian gerbil (a kind of sand rat) was investigated by light and electron microscopy. Subepithelial connective tissue papillae of palatine rugae contained a dense distribution of lamellated corpuscles that showed an ultrastructure similar to that of Meissner corpuscles of primates. The corpuscles in the palate of the mongolian gerbil, however, frequently formed compound large corpuscles with a palisade-like extension. Antemolar rugae predominated in containing such compound "Meissner" corpuscles. Superficial cytoplasmic lamellae of the corpuscles closely adhered to overlying epithelial cells without an intervening basal lamina. Although a small number of simple corpuscles was seen in the first antemolar rugae, no similar corpuscles were encountered in other parts of the palate. On the other hand, numerous Merkel cell-nerve endings were seen in epithelial pegs and sometimes in epithelial ridges of palatine rugae. Quinacrine labelling showed that intermolar rugae contained a rather dense distribution of Merkel cells in comparison with antemolar rugae. The present and previous data indicate that the pattern of palatine mechanoreceptors of the mongolian gerbil is analogous to that of the mouse, but not of the rat.

The present study was designed to demonstrate the short term mineralization of dentin and enamel, and to investigate the effects of sodium beta-glycerophosphate (Na-beta-GPO4) on calcification in a serum-free, chemically-defined medium. The first mandibular molars at the bell stage dissected from 18-day-old mouse embryos were used as explants, which were cultured by an improved flotation method. Calcification of enamel in the 18-day-old embryonic molars occurred within the 6th day of culture. In another experiment, the molar germs were cultured in a serum-free, chemically-defined medium supplemented with 1, 5 and 10 mM Na-beta-GPO4. Promotion of tooth mineralization was recognizable at very low concentrations, such as 1 mM Na-beta-GPO4, in 18-day-old embryonic tooth germs. The culturing system reported here shortens the time required for dentin and enamel calcification to one half or one third of that reported previously and therefore should prove useful for examining regulations for cytodifferentiation and morphogenesis in tooth germs and the mineralization of dentin and enamel.

A hybrid NiCrAl pressure cell was fabricated to measure magnetic quantities above 3 GPa. A pressure of 4 GPa was achieved and the pressure cell was found to be reusable even after pressurizing trial up to 4GPa. The inner diameter of the cylinder expanded 2.5% at 4 GPa. The pressure cell was applied to the 63Cu-NMR measurement at an optimum pressure of 3.8 GPa in a pressure-induced superconductor Sr2Ca12Cu24O41.

A ganglionated nerve plexus (GNP) found in the nasal vestibular mucosa of the adult musk shrew, and most likely belonging to the nervus terminalis, was studied by electron microscopy. The GNP, which contained ganglion cells and both myelinated and unmyelinated nerve fibers, was located in the subepithelial layer of the mesial vestibular mucosa of the snout processes. The ganglion cells were characterized by an eccentrically located round nucleus, dispersed mitochondria and Golgi apparatuses, and many small vesicles. Nissl bodies were rare. The ganglion cells, solitary or in a small group, were entirely covered with satellite cell sheaths. Semiserial sections suggested that a given ganglion cell directly extends one nerve process and plural modified cilia. There were no synaptic contacts between the ganglion cells and efferent nerve elements. On the other hand, it was seen that the epithelium overlying the GNP contained many nerve terminals which probably originated from the GNP. It is suggested that the ganglion cells in the nasal vestibular GNP of the musk shrew represent primary sensory neurons.

We found that when the midsection of Meckel's cartilage bars obtained from mice on the eighteenth day of gestation were grafted into isogenic mouse spleen, chondrocytes induced an endochondral calcification. Concurrent with the onset of calcification throughout Meckel's cartilage matrix, periodic banded thick collagen fibrils and matrix vesicles were observed around the chondrocytes. Although most of the chondrocytes prior to grafting were hypertrophic cells, they survived for seven days in the splenic tissue and had well-developed secretory organelles. The cells which were surrounded by calcified matrix were relatively small, spherical, and showed a morphology closely resembling that of osteocytes. These findings suggest that the life span of hypertrophic chondrocytes is influenced by the microenvironment of the spleen.

Nuclear magnetic resonance (NMR) on copper nuclei has been performed in the ladder system Sr(ZnxCu1 − x)2O3. The NMR lines for the Zn-doped samples (0.25%) show drastic broadening at low temperatures below 100 K, while not for the pure samples. The broadening is not explained by the free spins with short correlation length (ξ/a ∼ 3–4) which is expected in a spin-gap system, and suggests that the staggered moments are induced even on the sites far away from the impurities.

The low-temperature behaviors of the T 1 of protons in the Haldane-gap system TMNIN (pure and 4.9% doped with Zn +2 ) are interpreted in the framework that the fractional spins of S = ½ act as a thermal reservoir. Our model considers that the relaxation (or correlation) time of longitudinal component S z of the fractional spin, which is of the order of nuclear Larmor period, is determined by collisions with low-density Haldane excitations.

Nuclear magnetic resonance (NMR) for 7Li nuclei was performed in vanadium spinel, LiV2O4. An anomalous temperature dependence of the relaxation time T1 was observed. Namely, the relaxation rate 1/T1 first increases with increasing temperature and then decreases below about 50 K. Such an anomalous temperature dependence may reflect the critical behavior around the ferromagnetic instability predicted by the SCR theory.

The results of magnetic susceptibility, electrical resistivity ($\rho$), heat-capacity (C) and thermopower (S) measurements on CeCuAs2, forming in ZrCuSi2-type tetragonal structure, are reported. Our investigations reveal that Ce is trivalent and there is no clear evidence for long range magnetic ordering down to 45 mK. The $\rho$ behavior is notable in the sense that (i) the temperature (T)-coefficient of $\rho$ is negative in the entire range of measurement (45 mK to 300 K) with large values of $\rho$, while S behavior is typical of metallic Kondo lattices, and (ii) $\rho$ is proportional to T-0.6 at low temperatures, without any influence on the exponent by the application of a magnetic field, which does not seem to classify this compound into hither-to-known non-Fermi liquid (NFL) systems. In contrast to the logarithmic increase known for NFL systems, C/T measured down to 0.5 K exhibits a fall below 2 K. The observed properties of this compound are unusual among Ce systems., Comment: PRB, in press

Doping effect of nonmagnetic impurities such as Zn 2+ or Hg 2+ in the Haldane system Ni(C 2 H 8 N 2 ) 2 NO 2 (CIO 4 )(NENP) was studied through SQUID measurement. Temperature and field dependences for these samples were measured. It is found from the experimental results that magnetic moments appear in the spin system by cutting linear chain with nonmagnetic impurities.

Mode-hop-free wavelength tuning of 4.45 nm was achieved by a short-active-region distributed Bragg reflector laser without phase control. Simple and continuous tuning was realised with a single tuning current. High-speed wavelength tuning of 5 ns during direct modulation of 2.5 Gbit/s was also achieved.

The longitudinal and transverse relaxation times of 133Cs were measured in the ordered phase of CsCoCl3. From an analysis of fluctuating internal field at the Cs nuclei, the experimental results were interpreted in terms of the spin inversion caused by the propagation of domain-wall pair in the Co2+ chain.

NMR spectrum and nuclear spin relaxation time of 133 Cs in CsMnI 3 were measured to study the spin dynamics in a triangular lattice Heisenberg antiferromagnet. Characteristic motions such as a rotation around the c -axis and a swinging motion of the 120° spin structure were revealed.

The proton spin-lattice relaxation time T 1 in the Haldane-gap system, Ni(C 2 H 8 N 2 ) 2 NO 2 (ClO 4 ) was measured down to 0.5 K. The development of antiferromagnetic short range order was not found even at low temperatures. A relaxation process of activation type with an energy gap of 11 K has been observed.

Mandibular first molars in mice ranging in age from 18 days prenatal to 5 days postnatal were used for light and electron microscopic examinations of the enamel-free area (EFA) during development of the occlusal cusp (mesiobuccal cusp). Notable morphological changes in the inner enamel epithelium and the cells of the stratum intermedium were observed. At prenatal age of 18 days, the inner enamel epithelium of the EFA (EFA epithelium) was composed of a layer of columnar cells and covered by the cells of the stratum intermedium. Two days after birth, the EFA epithelium was made up largely of preameloblasts, with mitochondria located in the proximal side of the cells toward the stratum intermedium. The cells of the stratum intermedium were irregularly shaped, with wide intercellular spaces between them. At a postnatal age of 3 days, most of the EFA epithelial cells resembled maturation-stage ameloblasts, being short and columnar in shape and having nuclei located in their proximal side. Distal cell membranes were folded, and mitochondria were scattered throughout the cytoplasm. In 4-day-old mice, the EFA epithelium was found to be formed of short columnar or cuboidal cells with distinct intercellular spaces. The cells of the stratum intermedium could no longer be detected, and cells of the EFA epithelium could not be distinguished from those of the stellate reticulum. Odontoblasts of the EFA were arranged and polarized parallel to the basal lamina, and odontoblastic processes extended toward the cusp tip. The orientation of thin and thick collagen fibers within predentin and dentin was also parallel to the basal lamina. Even after dentin mineraliza tion, disrupted basal lamina and long, aperiodic, fine fibrils were found between the epithelium and the dentin. Following the disappearance of the basal lamina and fine fibrils, stippled material and crystals appeared on the dentin surface. The mineralized matrix, which x-ray microanalytical energy peaks identified as containing calcium and phosphorus, was continuous with enamel in the distal slope of the cusp at the cusp tip. Thus, the inner enamel epithelium of the EFA differentiated into secretory cells capable of enamel-like matrix formation. In conclusion, development of EFA in mouse molars seems to be a system suitable for use in studying both the involvement of extracellular matrix, including basal lamina constituents, in ameioblast differentiation, and the role of the cells of the stratum intermedium, together with the ameloblasts, in comprising a single functional unit responsible for enamel formation.

Tooth pulps dissociated intact with EDTA were isografted for up to 40 days, and examined by light and electron microscopy for hard tissue morphodifferentiation. Grafts formed tubular dentine and osteodentine. Tubular dentine, penetrated regularly by elongated odontoblast processes, resembled normal dentine and was formed when the original odontoblasts continued normal matrix secretion. Osteodentine was formed by spindle-shaped cells with large round nuclei which presumably were transformed pulp cells, and incorporated the same elements as found in cells of non-tubular dentine. Occasionally, odontoblasts were contiguous with both the regular dentine and the osteodentine. Thus in EDTA-dissociated pulps transplanted to the spleen, the original odontoblasts produce tubular dentine and other pulp cells differentiate to form osteodentine.

Lamellated sensory corpuscles in the perioral tissues of the adult cat and the adult miniature pig were studied by light and electron microscopy. In the cat lip, over half of the lamellated corpuscles existed in an aggregate form associated with other nerve elements and blood capillaries in peripheral nerve swellings, while the remainder existed in an isolated form. Conversely, almost all the lamellated corpuscles in the miniature pig existed in an aggregate form in nerve swellings. Most of the intraperineural lamellated corpuscles showed ultrastructural characteristics of simple corpuscles. However, some of the intraperineural lamellated corpuscles exhibited interlaced arrangements of tortuous axon terminals and cytoplasmic lamellae resembling the arrangement in Meissner corpuscles. Immunohistochemical staining using anti-neuron specific enolase also revealed the presence of intraperineural, Meissner-like corpuscles in the cat lip. This study indicates that intraperineural localization of lamellated corpuscles is common in carnivora and artiodactyla and that the intraperineural lamellated corpuscles are heterogeneous in their ultrastructural pattern.

Mandibular first molars from 17-day-old mouse embryos were cultured for 2 and 4 days in alpha-MEM supplemented with 10% newborn bovine serum containing 0.02% ethanol or 0.1, 1.0 or 10 ng/ml 1,25-(OH)2D3. After embedding, every 6th section was stained and mitotic features of inner dental epithelium (IDE) and dental papilla cells (DP) were counted under a light microscope. On the 2nd day, no significant differences were observed in the IDE and DP mitotic indexes among the control, ethanol, and the three vitamin D groups. On the 4th day, the indexes for all groups decreased. But the IDE indexes for all vitamin D groups were significantly different from those for the control (P less than 0.01) and ethanol (P less than 0.05) groups, whereas the DP index was significant (P less than 0.05) only in the 10 ng/ml vitamin D group. The present results suggest that vitamin D3 may have an influence on cell proliferation of IDE and DP in mouse embryonic molars in vitro.

The prototypical iron-based high-Tc pnictide LaFeAsO1–xHx has superconducting double domes in the electronic phase diagram. Pressure application merges the double domes into a single dome, and the minimum Tc of 26K observed at x=0.2 goes up to 45K by applying a pressure of 3.0GPa. 75As nuclear magnetic resonance was performed at 3.0GPa to investigate the high-Tc mechanism. The relaxation rate divided by temperature, 1/T1T exhibits a plateau just above Tc and the value is enhanced by applying pressure. The plateau indicates that 1/T1 can be described by the Korringa relation, which suggests that a key factor to raise Tc is the density of states. So far as our results are concerned, spin fluctuations are not essential to achieve high Tc over 45K.

BackgroundCauses of left atrial (LA) enlargement and its gender difference in patients with normal left ventricular (LV) systolic function have not been clarified. We investigated the factors contributing to LA enlargement in patients with normal LV systolic function, addressing its gender difference.MethodsWe enrolled 380 patients (175 males and 205 females; mean age: 63±15 years) with LV ejection fraction ≥50% who underwent Doppler echocardiography and blood tests at the same time as echocardiography. Patients with arrhythmias, significant valvular heart disease, and LV asynergy were excluded. The LA volume was measured by Simpson's method from apical 2- and 4-chamber views, and LA volume index (LAVI) was calculated as LA volume/body surface area. All patients, male and female were assigned to a group with a low or a high LAVI based on the median LAVI value, respectively.ResultsAge, female gender, hypertension, diabetes, hemoglobin concentration, LV mass index, Doppler parameters of LA contraction, and the ratio of mitral early diastolic velocity to early diastolic velocity of the mitral annulus (E/E′) were significantly associated with a high LAVI in all patients. Multivariate analysis showed that LV mass index [odds ratio (OR) 1.05, 95% confidence interval (CI) 1.03–1.06, P

Mandibular first molars of mouse embryos were cultivated for examination of the effects of calcitonin (CT) and/or parathyroid hormone (PTH) on the odontogenesis of the molars, and for determination of whether and how CT, which is a PTH antagonist, has an influence on the effect of PTH on odontogenesis. On the second day, the inner enamel epithelium in the control group had already differentiated into pre-ameloblasts. Typical odontoblasts had secreted a layer of pre-dentin. On the fourth day of culture, the pre-ameloblasts achieved terminal differentiation into secretory ameloblasts, and enamel and dentin had already been deposited. PTH (1 unit/mL) inhibited the odontogenesis of the cultured molars during the designated culture periods (two and four days), while CT (0.5 unit/mL) stimulated odontogenesis. On the second day, the development of the molars in the CT + PTH group showed an intermediate stage between the control and PTH-treated explants, but on day 4 it corresponded to that of the controls. Moreover, when the molars exposed to PTH for two days were untreated and treated with CT for an additional two days, the former produced a small yuantity of enamel matrix, while the latter formed a large amount of the matrix. These histological findings were also supported by a morphometric analysis of the enamel matrix in the cultured molars. The present results suggest that CT stimulates, but PTH suppresses, the odontogenesis of the mouse embryonic molars, and that CT is an antagonist to the inhibitory effect of PTH on odontogenesis.

Mandibular first molars from 17-d-old mouse embryos were cultured in vitro for 2 to 4 d by a simple, disposable, improved floatation method. This method consisted of using a 24-well multidish and a plastic culture chamber with a membrane filter. The improved floatation method, as well as our previous method, was capable of the three-dimensional development of tooth germs. Cytodifferentiation of odontoblasts and ameloblasts and formation of extracellular matrices were accelerated by the present culture system, in comparison with our previous method. All the molars cultivated by this method were very similar in morphology to in vivo. On Day 2 of culture the terminal cytodifferentiation of odontoblasts and the formation of predentin were ascertained in the bucco-lingual sections of the cultured molars. A thick layer of predentin was formed at the tip of the cusp and gradually decreased toward the cervical loop and the fissure between the buccal and lingual cusps. On Day 4 in vitro, secretory ameloblasts produced enamel matrix, and the mineralized enamel showed showed prismatic structure very similar to that in vivo. Dentin and predentin also were normal in ultrastructure. The extracellular matrices (enamel, dentine, and predentin) were formed in line with the pattern of the cusp and the formation of matrices normally started at the tip of the cusp. We conclude that the three-dimensional development of whole tooth germs in vitro may be very important for normal expression of the developmental program intrinsic to mouse embryonic molars.

Tooth germs taken from 13-day-old embryonic mice and isografted in the spleen of adult mice were examined by light and electron microscopy. Well-organized tooth structures from the early cap stage to fully developed and mineralized mature teeth were obtained up to day 60 after transplantation. Germs on day 2 were similar to those prior to the onset of grafting but reached the late cap stage of development on day 4. On day 6, enamel and dentine formation were initiated and inner enamel epithelium and dental papilla cells were polarized. On days 10–15, enamel-matrix secretion was completed and almost all ameloblasts had become resorptive enamel epithelium. India ink injected from the recipient caudal vein accumulated to the capillaries within the pulp throughout the newly-formed vessels. On day 20, defined root formation had begun but occasionally irregular and cellular osteodentine was formed in root areas. On day 30, transplants were covered with reduced enamel epithelium and acellular cementum was formed at the root areas together with rudimentary periodontal ligament fibres. Cellular cementum became thicker up to day 40. There was little evidence of cellular infiltration from recipient tissue up to day 60. The spleen seems to be a suitable site for transplantation of tooth germs.

The Japanese queenless ponerine ant Diacamma sp. from Japan employs tandem running during nest relocation, in which a leader ant guides nestmate followers one at a time. We replicated this process by presenting one entire abdominal part of a leader, except for the petiole to followers. When the abdominal part had been rinsed with n-hexane, however, it attracted significantlyfewer followers. This suggests that chemicals on the leader’s abdominal part evoke tandem running. Dissection of abdominal major exocrine glands revealed that the Dufour’s gland was the source of this chemical signal. The chemicals were eluted in the hydrocarbon fraction by silica-gel column chromatography, and the quantitatively major component was estimated as heptadecene (C17:1) through gas chromatograph-mass spectrometer (GCMS) analysis. The position of the double bond was estimated to be between the 8th and 9th carbons through analysis of the epoxidized compound. Only (Z)-isomers of 8-heptadecene evoked tandem running in the followers. We identified the tandem running pheromone of this ant species to be (Z)-8- heptadecene. (163)