Waveform analysis of ocular blood flow and the early detection of normal tension glaucoma

PURPOSE

To investigate waveform changes in blood flow (BF) in the optic nerve head (ONH) and to evaluate their usefulness in identifying normal tension glaucoma (NTG).

METHODS

Sixty-one eyes of 61 patients with NTG and 21 eyes of age-matched healthy control subjects were included in this study. The NTG eyes were divided into the following three groups based on the progression of their visual field defects: mild (mean deviation [MD] greater than -6.0 decibels [dB]), moderate (MD between -6.0 and -12.0 dB), and severe (MD less than -12.0 dB). The ONH BF analysis was performed with laser speckle flowgraphy (LSFG) and included waveform variables such as skew, acceleration time index (ATI), and blowout time.

RESULTS

In the ONH, LSFG skew variables were significantly lower in the NTG eyes than in the control eyes (P < 0.001), and ATI was significantly higher (P < 0.01), despite similar systemic characteristics in the four groups. The differences were most marked in the mild NTG group. Multiple linear regression analysis showed that MD, average thickness of the circumpapillary retinal nerve fiber layer, and pulse rate were predictive factors for both skew and ATI. A receiver operating characteristic (ROC) curve analysis also revealed that skew (area under the ROC curve, 0.89) and ATI (area under the ROC curve, 0.80) had the greatest power to differentiate normal eyes from eyes with mild NTG.

CONCLUSIONS

These results suggest that LSFG measurements of waveform changes in ONH BF can differentiate healthy eyes from eyes with NTG, particularly those with mild NTG.

Association between optic nerve blood flow and objective examinations in glaucoma patients with generalized enlargement disc type

BACKGROUND

The purpose of this study was to investigate the correlations between microcirculation in the optic disc, average peripapillary retinal nerve fiber layer thickness cupping parameters, and visual field defects in glaucoma patients with the generalized enlargement disc type.

METHODS

A total of 38 eyes from 38 glaucoma patients with the generalized enlargement disc type were included. The microcirculation of the optic nerve head was examined with laser speckle flow graphy, and the mean blur rate in all areas, in vessel area, and in tissue area were calculated using the laser speckle flow graphy analyzer software. Average peripapillary retinal nerve fiber layer thickness was measured using Stratus optical coherence tomography, and cupping parameters were accessed using the Heidelberg retina tomograph. The mean deviation in the Humphrey field analyzer (30-2 SITA standard) was analyzed. The correlation between these parameters was evaluated using the Spearman rank correlation coefficient.

RESULTS

The correlation coefficient of mean blur rate in all optic disc area to the average peripapillary retinal nerve fiber layer thickness, vertical C/D, and mean deviation were r = 0.7546 (P < 0.0001), r = -0.6208 (P < 0.0001), and r = 0.6010 (P = 0.0001), respectively. The mean blur rate in tissue area of the optic disc showed r = 0.7305 (P < 0.0001), r = -0.6438 (P < 0.0001), and r = 0.6338 (P < 0.0001).

CONCLUSION

We found that the mean blur rate in the optic disc was significantly correlated with the average peripapillary retinal nerve fiber layer thickness, vertical C/D, and mean deviation in patients with the generalized enlargement disc type of glaucoma. In particular, the mean blur rate in tissue area was more highly correlated than the vessel area with other results of examination in glaucoma patients with the generalized enlargement disc type.

High-Quality Polycrystalline Silicon Thin Film Prepared by a Solid Phase Crystallization Method

We succeeded, for the first time, in depositing a silicon film which features 1000Å-wide single-crystalline grains embedded in a matrix of amorphous tissue. The deposition was done by plasma-enhanced CVD from silane diluted with hydrogen at a considerably high temperature (550°C). 5pm-thick undoped amorphous silicon film was deposited on the above film and was crystallized by a solid phase crystallization method. The polycrystalline silicon film which was obtained has a columnar structure and shows an extremely high electron mobility of 808 cm2/Vs.

High-Quality A-Si Films Prepared by the Direct Photo-Cvd Method

A high-efficiency integrated-type a-Si solar cell submodule with a size of 10cm × 10cm has been fabricated and a total area efficiency of 9.6% is obtained by using a high-quality p-layer doped with B(CH3)3 We have developed an advanced direct photo-CVD method. High-quallt” a-SI films with low tail characteristic energy and low light-induced degradation is prepared by this method. We have also studied the role of Si-H2 bonds on the light-induced effect. The result implies that Si-H bonds stabilize the defect states, resulting in a large light-induced degradation.

Hydrogenated Amorphous Silicon Germanium Alloy for Stable Solar Cells

The film properties and solar cell performance of a-SiGe:H samples with the same optical gap and different combinations of hydrogen content (CH) and germanium content (CGe) have been compared. The optimum composition for the initial properties, such as the tail characteristic energy, defect density and conversion efficiency of the solar cell, was determined, and the differences could be explained by the difference in H bonding configuration. The degradation ratio of the conversion efficiency becomes larger in higher CH samples. This suggests that hydrogen or Si-H2 participates in light-induced degradation. As a result, the optimum CH for an efficient solar cell is believed to shift to the lower CH region after light soaking. Based on these findings, the stabilized conversion efficiency of 3.3% under red light (γ>650nm) for an a-SiGe:H single-junction solar cell (1cm2) and 10.6% under lsun light for an a-Si/a-SiGe double-junction stacked solar cell (1cm2) have been achieved. The degradation ratio is only 8.6% for the double-junction solar cell.

Lateral Grain Growth in the Excimer Laser Crystallization of Poly-Si

We have succeeded in obtaining nondoped, thin poly-Si film (thickness ∼500Å) with excellent crystallinity and large grain size (Maximum grain size ∼4.5 μ m) by an excimer laser annealing Method, which offers the features of low-temperature processing and a short processing time. The grain size distribution shrinks in the region around 1.5 μ m and this poly-Si film exhibits a strong (111) crystallographic orientation. Poly-Si thin film transistors using these films show quite a high field effect mobility of 440cm2/V · s below 600°C process.

Analysis of the effect of structural materials in a wall-less tissue-equivalent proportional counter irradiated by 290 MeV u(-1) carbon beam

Effects of structural materials in a wall-less tissue-equivalent proportional counter were evaluated based on the calculation of energy deposits by EGS5 and the measurement of lineal energy distributions using 290 MeV u(-1) carbon beams. It is found that the correction of measured data based on simulation is necessary for understanding the energy deposition spectra in the homogeneous condition in tissues.

Anomalous state sandwiched between Fermi liquid and charge ordered Mott-insulating phases of Ti4O7

The Magnéli phase Ti(4)O(7) exhibits two sharp jumps in resistivity with coupled structural transitions as a function of temperature at T(c1) approximately 142 K and T(c2) = 154 K. We have studied electronic structure changes across the two transitions using 7 eV laser, soft x-ray, and hard x-ray (HX) photoemission spectroscopy (PES). Ti 2p-3d resonant PES and HX PES show a clear metallic Fermi edge and mixed valency above T(c2). The low temperature phase below T(c1) shows a clear insulating gap of approximately 100 meV. The intermediate phase between T(c1) and T(c2) indicates a pseudogap coexisting with remnant coherent states. HX PES and complementary calculations have confirmed the coherent screening in the strongly correlated intermediate phase. The results suggest the existence of a highly anomalous state sandwiched between the mixed-valent Fermi liquid and charge ordered Mott-insulating phase in Ti(4)O(7).

Kondo scaling of the pseudogap in CeOs4Sb12 and CeFe4P12

CeOs(4)Sb(12) and CeFe(4)P(12) are classified as Kondo semiconductors, which show coupled changes in electrical transport, thermodynamic and magnetic properties with a low-temperature semiconductor-like electrical resistivity. We have carried out core level and valence band photoemission spectroscopy on single crystal CeOs(4)Sb(12) and CeFe(4)P(12) to study their electronic structure and the evolution of states at the Fermi level as a function of temperature (∼10-300 K). The Ce 3d core level spectra show the presence of f(0), f(1) and f(2) final states with very different relative intensities in the two compounds. Single-impurity Anderson model calculations provide f electron counts of n(f) = 0.97 and 0.86 per Ce atom, suggestive of a low- and high-T(K) (= single ion Kondo temperature) for CeOs(4)Sb(12) and CeFe(4)P(12), respectively. The high-resolution temperature-dependent near-Fermi level spectra show pseudogaps of energy ∼ 50 meV and ∼ 110 meV in the valence band density of states (DOS) of CeOs(4)Sb(12) and CeFe(4)P(12), respectively. The temperature dependence of the DOS at the Fermi level follows the change in effective magnetic moment estimated from magnetic susceptibility for both materials, confirming the Kondo nature of the pseudogap in CeOs(4)Sb(12) and CeFe(4)P(12). A compilation of measured pseudogaps using photoemission and optical spectroscopy identifies the charge gaps Δ(C) for Ce-based Kondo semiconductors and provides a direct relation with T(K) given by Δ(C) ∼ 2k(B)T(K). In conjunction with the known behaviour of the spin gaps Δ(S) ∼ k(B)T(K), the results establish the coupled energy scaling of the spin and charge gaps in Kondo semiconductors.

Strong mass renormalization at a local momentum space in multiorbital Ca1.8Sr0.2RuO4

We have studied the mass renormalization in Ca2-xSrxRuO4 (x=0.2) using high-resolution angle-resolved photoemission spectroscopy. We observed precise band dispersions near the Fermi level (E_{F}) and the corresponding Fermi surfaces. A characteristic flat band with approximately 4 meV dispersion accompanying sharp quasiparticle (QP) peaks shows up in a limited momentum region around (pi, 0). The QP peak rapidly evolves below the crossover temperature T;{*} approximately 20 K, which agrees well with the mass enhancement behavior indicated by thermal, magnetic, and transport properties. We discuss the origin of the mass renormalization in relation to the local flat band at (pi, 0) possibly derived from the gamma (d_{xy}) band.

Study of audio speakers containing ferrofluid

This work validates a method for increasing the radial restoring force on the voice coil in audio speakers containing ferrofluid. In addition, a study is made of factors influencing splash loss of the ferrofluid due to shock. Ferrohydrodynamic analysis is employed throughout to model behavior, and predictions are compared to experimental data.

Temperature-dependent localized excitations of doped carriers in superconducting diamond

Laser-excited photoemission spectroscopy is used to show that the doped carriers in metallic or superconducting diamond couple strongly to the lattice via high-energy (approximately 150 meV) optical phonons, with direct observations of localized Franck-Condon multiphonon sidebands appearing as Fermi-edge replicas. It exhibits a temperature-dependent spectral weight transfer from higher to lower energy sidebands and zero-phonon Fermi-edge states. The quantified coupling strength shows a systematic increase on lowering temperature, implicating its relation to the normal state transport and superconductivity.

High temperatures activate local viral multiplication and cell-to-cell movement of Melon necrotic spot virus but restrict expression of systemic symptoms

The infection of melon plants by Melon necrotic spot virus (MNSV) and the development of necrotic disease symptoms are a seasonal occurrence in Japan, which take place between winter and early summer, but not during mid-summer. In this paper we investigate the effect of three different temperatures (15, 20, and 25 degrees C) on the local and systemic expression of MNSV in melon plants. Previously, the incidence of plants expressing systemic symptoms caused by MNSV and other viruses was found to be greater at temperatures less than 20 degrees C. In this study, our temperature-shift experiments support previous studies that found the expression of systemic symptoms increases as temperature falls from 25 to 20 degrees C and decreases as temperature rises from 20 to 25 degrees C. However, MNSV replication in melon cells and local viral movement within leaves following the inoculation of melon protoplasts or cotyledons were more frequent at 25 degrees C than at 15 or 20 degrees C.

Bulk electronic structure of the antiferromagnetic superconducting phase in ErNi2B2C

We have performed temperature- (T-)dependent laser-photoemission spectroscopy of the antiferromagnetic (AF) superconductor ErNi2B2C to study the electronic-structure evolution reflecting the interplay between antiferromagnetism and superconductivity. The spectra at the superconducting (SC) phase show a very broad spectral shape. A T-dependent SC gap shows a sudden deviation from the BCS prediction just below TN. This observation can be explained well by the theoretical model and thus represents the characteristic bulk electronic structure of the AF SC phase for the first time.

Observation of a superconducting gap in boron-doped diamond by laser-excited photoemission spectroscopy

We investigate the temperature (T)-dependent low-energy electronic structure of a boron-doped diamond thin film using ultrahigh resolution laser-excited photoemission spectroscopy. We observe a clear shift of the leading edge below T=11 K, indicative of a superconducting gap opening (Delta approximately 0.78 meV at T=4.5 K). The gap feature is significantly broad and a well-defined quasiparticle peak is lacking even at the lowest temperature of measurement (=4.5 K). We discuss our results in terms of disorder effects on the normal state transport and superconductivity in this system.

Calculation of energy distributions of charged particles produced by neutrons from 0.14 to 65 MeV in tissue substitutes

Energy distributions of secondary charged particles were calculated in tissue substitutes irradiated by neutrons from 0.14 to 65 MeV, using the Particle and Heavy Ion Transport code System. The calculations were compared with experimental data measured by tissue equivalent proportional counters (TEPC). It is found that the calculated distributions of the lineal energy, y, generally agree well with the measured ones for neutrons from several 100 keV to 15 MeV. In the case of 40 and 65 MeV neutron irradiations, wall effects of TEPC should be considered and the fluence of alphas is underestimated by the calculations. Integrated dose contributions of the secondary charged particles are generally in good agreement with those of the measured ones.

Angle-resolved photoemission study of the cobalt oxide superconductor Na(x)CoO(2) x yH(2)O: observation of the Fermi surface

The cobalt oxide superconductor Na(x)CoO(2) x yH(2)O is studied by angle-resolved photoemission spectroscopy. We report the Fermi surface (FS) topology and electronic structure near the Fermi level (E(F)) in the normal state of Na(x)CoO(2) x yH(2)O. Our result indicates the presence of the hexagonal FS centered at the Gamma point, while the small pocket FSs along Gamma-K direction are absent, similar to Na(x)CoO(2). The top of the e(g)(') band, which is expected in band calculations to form the small pocket FSs, extends to within approximately 30 meV below E(F), closer to E(F) than in Na(x)CoO(2). We discuss its possible role in superconductivity, comparing with other experimental and theoretical results.

Intermittent hyperthermia enhances skeletal muscle regrowth and attenuates oxidative damage following reloading

Skeletal muscle reloading following disuse is characterized by profound oxidative damage. This study tested the hypothesis that intermittent hyperthermia during reloading attenuates oxidative damage and augments skeletal muscle regrowth following immobilization. Forty animals were randomly divided into four groups: control (Con), immobilized (Im), reloaded (RC), and reloaded and heated (RH). All groups but Con were immobilized for 7 days. Animals in the RC and RH groups were then reloaded for 7 days with (RH) or without (RC) hyperthermia (41-41.5 degrees C for 30 min on alternating days) during reloading. Heating resulted in approximately 25% elevation in heat shock protein expression (P < 0.05) and an approximately 30% greater soleus regrowth (P < 0.05) in RH compared with RC. Furthermore, oxidant damage was lower in the RH group compared with RC because nitrotyrosine and 4-hydroxy-2-nonenol were returned to near baseline when heating was combined with reloading. Reduced oxidant damage was independent of antioxidant enzymes (manganese superoxide dismutase, copper-zinc superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase). In summary, these data suggest that intermittent hyperthermia during reloading attenuates oxidative stress and improves the rate of skeletal muscle regrowth during reloading after immobilization.

Low-energy charge-density excitations in MgB2: Striking interplay between single-particle and collective behavior for large momenta

A sharp feature in the charge-density excitation spectra of single-crystal MgB2, displaying a remarkable cosinelike, periodic energy dispersion with momentum transfer (q) along the c* axis, has been observed for the first time by high-resolution nonresonant inelastic x-ray scattering (NIXS). Time-dependent density-functional theory calculations show that the physics underlying the NIXS data is strong coupling between single-particle and collective degrees of freedom, mediated by large crystal local-field effects. As a result, the small-q collective mode residing in the single-particle excitation gap of the B pi bands reappears periodically in higher Brillouin zones. The NIXS data thus embody a novel signature of the layered electronic structure of MgB2.

Frankliniella cephalica, a New Vector for Tomato spotted wilt virus

Frankliniella cephalica (Crawford) is an invasive species of thrips found in the islands of Yaeyama in the Okinawa Prefecture, Japan. During the late 1990s to early 2000s, a species of thrips was isolated from wild flowers of Bidens pilosa L. and Ipomoea batatas L. growing close to cultivated fields. They were subsequently identified as F. cephalica using fine morphological characteristics with the help of Steve Nakahara (U.S. Department of Agriculture, Beltsville, MD) and Laurence Mound (CSIRO, Australia). Voucher specimens were deposited in the Laboratory of Insect Resources, Faculty of Agriculture, Tokyo University of Agriculture by Shuji Okajima (2). We investigated the ability of F. cephalica to vector Tomato spotted wilt virus (TSWV) by experimentally determining virus transmission efficiency. Newly hatched larvae as much as 12 h old underwent a viral acquisition-access period (AAP) of 24 h, during which they fed on the leaves of Datura stramonium infected with TSWV-O, a Japanese type isolate. Transmission efficiency of adults 4 days after emergence from molt (14 days after the AAP) was determined by a petunia leaf disk assay (3) in which the adults were individually allowed to feed for successive 24-h inoculation access periods (IAP) on two different leaf disks of Petunia × hybrida cv. Polo Blue. Transmission of the virus by the adults was considered positive if at least one of the leaf disks showed viral necrotic spot. We tested 20 randomly selected leaf disks with clear necrotic spots using a simplified rapid immunofilter paper assay. All selected disks were positive for TWSV. The transmission efficiencies were 24.6% for female (n = 57) and 54.4% for male (n = 125) adults. The efficiency was significantly different between sexes (Fisher's exact probability test, P < 0.001). We also examined changes in the virus infection site at different developmental stages in thrips using immunofluorescence microscopy with a polyclonal antibody to N protein of the virus (4). After a 6-h AAP feeding by first instar larvae, the virus was found initially to infect the epithelial cells and then spread throughout the midgut tissue in the second instar larvae 5 days after acquisition of the virus. In viruliferous adults, the virus was present in the salivary glands and on the basement membrane of the midgut tissue. These data indicate that F. cephalica is a new insect vector for TSWV. F. cephalica is a major insect pest of tropical crops in tropical and subtropical coastal belts (1). The presence of a thrips vector in weed hosts surrounding cultivated fields might increase the chance of crops in this habitat becoming infected with viruses. References: (1) M. Lamberts and J. H. Crane. Page 337 in: Advances in New Crops. J. Janick and J. E. Simon, eds. Timber Press, Portland, OR, 1990. (2) M. Masumoto and S. Okajima. Jpn. J. Appl. Entomol. Zool. 48:225, 2004. (3) T. Sakurai et al. Appl. Entomol. Zool. 39:71, 2004. (4) S. Tsuda et al. Ann. Phytopathol. Soc. Jpn. 60:216, 1994.