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Purpose: Intravitreal anti-vascular endothelial growth factor (VEGF) is a mainstream treatment for reducing ME secondary to BRVO (BVO-ME）. Regrettably, most reports of intravitreal anti-VEGF for BVO-ME have disclosed only short-term outcomes. Here, we characterized long-term indicators for the visual prognosis of patients with BVO-ME, including the correlation between retinal structure by OCT and visual acuity. Methods: Patients with BVO-ME were retrospectively recruited based on clinical records in Kansai Medical University Hospital from June 2012 to March 2022. Patients were divided into two groups according to BCVA at the final visit: Group A (≥0.7) and Group B (≤0.6). Results: 47 eyes from 45 patients were assessed. The mean follow-up period from initial to final visit was 64.38 ± 15.07 (range, 38-100) months. BCVA in Group A (n = 32) was significantly greater than in Group B (n = 15) at all timepoints. The ratio that the number of eyes which the EZ band and the foveal bulge were intact in Group A was higher than in Group B (p = 0.0004 and p = 0.0002, respectively). The ratio that the number of eyes which recurrence SRD was observed by the final visit in Group A was lower than in Group B (p = 0.0485). Conclusion: The integrity of the EZ band and an intact foveal bulge were significant predictors for visual acuity. In contrast, recurrent SRD led to poor visual acuity in the long term, even if BCVA was good in the short term.

Purpose: To investigate the surgical outcomes of trabeculotomy ab interno/externo with cataract surgery in patients with primary open-angle glaucoma (POAG) and exfoliation glaucoma (XFG) in a 12-month follow-up study. Methods: This retrospective study enrolled 95 patients (121 eyes) with POAG or XFG who underwent trabeculotomy ab externo with a metal probe (M-LOT), ab interno with a Kahook Dual Blade® (K-LOT), or ab interno with a 5-0 nylon suture (S-LOT) between January 2015 and October 2022. Within these treatment groups, we assessed intraocular pressure (IOP), the number of IOP-lowering medications, the incidence of postoperative complications including hyphema with niveau and transient IOP spikes, and success rate using Kaplan–Meier survival analysis. Results: Median IOP was significantly reduced from baseline (p < 0.05) in the three patient groups, but the number of IOP-lowering medications was only significantly reduced in the M-LOT group. Kaplan–Meier cumulative survival analyses showed a lower success rate for K-LOT. M-LOT had the lowest incidences of hyphema and IOP spikes while S-LOT showed the highest incidences of these. Conclusions: M-, K-, and S-LOT had different surgical outcomes during the 12 months of follow-up, with M-LOT showing the fewest complications. These results will aid in choosing the most suitable trabeculotomy strategy for patients with POAG and XFG.

The direct-current electrical conductivities (σ) of 70V2O5∙30TeO2 (mol%) pelletized glasses annealed in an H2 gas atmosphere at 473 K were determined in the temperature (T) range of 322–473 K. Based on the log(σT)–T−1 relation in the considered temperature range, the electrical conduction is discussed in detail. The conduction of each glass sample at high temperatures (T > ~460 K) was attributed to nonadiabatic small polaron hopping. At T

A 78-year-old female experienced extraocular extension of a giant conjunctival melanocytic mass. The clinical diagnosis was conjunctival malignant melanoma. We performed local excision and histopathological examination. The result of hematoxylin-eosin staining disclosed multiple intralesional mucosal cysts and nevus cell nests with abundant melanin. Immunohistochemical examination revealed expression of S-100, melan-A, and HMB-45 and no expression of Ki-67. Histopathological examination showed no evidence of malignancy. Giant conjunctival melanocytic nevi can be diagnostically confused with conjunctival malignant melanoma.

To investigate factors contributing to the visual prognosis of choroidal neovascularization (CNV) secondary to angioid streaks (AS) in a long-term follow-up (> 5 years) study. Twenty-one patients (32 eyes) affected by CNV secondary to AS were enrolled retrospectively and divided into three groups according to the period of CNV recurrence from the final treatment: group A, no recurrence for more than 12 months; group B, no recurrence for 6–12 months; and group C, no recurrence for

Powdered 70V2O5·30TeO2 (mol%) glasses were annealed in an H2 gas atmosphere at 473 K for 1 h and 2 h, respectively. The difference between their physical properties before and after annealing was investigated. The mass of the powders decreased with an increase in the annealing time. Glass transition temperature (Tg) was 512 ± 0.1–513 ± 0.1 K for the annealed powders, indicating that the Tg values became lower than the as-quenched glass powder (Tg = 517 ± 0.1 K). The fraction of reduced vanadium ion (Cv = V4 + / (V4 + + V5 +)) increased with an increase in the annealing time: Cv = 0.020 ± 0.003, 0.024 ± 0.003 and 0.0272 ± 0.0033. From IR observation, it was determined that the glass structure in the annealed glasses ultimately incorporated a much larger amount of TeO3 trigonal pyramid units compared with the as-quenched glass powder. It was determined that the DC electrical conductivity (σ) of the pelletized powders, which were n-type semiconducting, depended on the annealing time of the powders. The largest σ was (5.78 ± 0.28) × 10− 5 S cm− 1 at 473 K for the pellet of the powder annealed for 2 h. The activation energy for electron hopping (W) was determined to be 0.380 ± 0.0005–0.420 eV ± 0.0005 eV, indicating that W decreased with an increase in the annealing time. The annealing contributed to the release of O from the glasses by changing the unit in the glasses from the TeO4 to TeO3: TeO4 + H2 → TeO3 + H2O ↑.

Background It is clinically recognized that collateral vessels can form after retinal vein occlusion (RVO) in some cases and these vessels can lead to spontaneous recovery of the pathological condition. In recent years, optical coherence tomography angiography (OCTA) has become a decisive clinical instrument. Unlike previous angiography tests, OCTA enables the non-invasive visualization of fundus vasculature without the need for administration of a contrast agent. However, it remains to be determined if OCTA depicts the ‘true’ histological status as several studies have reported artifacts in OCTA imaging. Methods We generated a laser-induced mouse RVO model, and evaluated the subsequent formation of collateral vessels in order to understand the mechanisms by which collateral vessels form using OCTA imaging, as well as molecular and histological assessments. Results We succeeded in visualizing the time course of collateral vessel formation in a mouse RVO model and confirmed the similarity in formation of collateral vessels only within the deep layer of the retina in both human and mouse. We hypothesized that sphingosine 1-phosphate receptor-1 (S1PR1) may play important roles via vascular shear stress linking vein occlusion and collateral vessel formation. Results from OCTA revealed that collateral vessels are increased in response to administration of a S1PR1 agonist in a mouse RVO model. Based on quantitative reverse transcription polymerase chain reaction (qRT-PCR), S1PR1 messenger ribonucleic acid (mRNA) levels in the whole retina peaked 6 h after photocoagulation in this model. Immunohistochemical staining of retinal flat mounts revealed that S1PR1 staining occurred along the laser-occluded blood vessels. Conclusion We observed the temporal process of collateral vessel formation in a mouse RVO model and identified the relationship between S1PR1 and shear stress as one of the factors in collateral vessel formation in RVO., OCTA; RVO; Collateral vessels.

Purpose To establish a new evaluation method to quantify residual ophthalmic viscosurgical device (OVD) volume and corneal endothelium adhesion properties for phacoemulsification surgery. Methods We compared the performance of four OVDs (Viscoat®, Healon5®, Healon® and DisCoVisc®) using porcine eyes. First, OVDs were mixed with fluorescent-conjugated dextrans to render them visible under the microscope. A corneal side port was opened, followed by a continuous curvilinear capsulorhexis, and a corneal tunnel incision was made. OVDs were injected, then the lens was removed using one-handed phacoemulsification. After this procedure, the anterior segment of the eye was isolated via an equatorial incision and the tissue was immediately frozen in shimmering liquid nitrogen. Sagittal slices (20 μm) were cut with a Cryostat from limbus to limbus. Every tenth slide was imaged using a fluorescent microscope with a CCD camera. We evaluated the percentage of the corneal endothelium covered by each OVD as the OVD adhesion to corneal endothelium ratio (OAE ratio) and the volume of residual OVD in the anterior chamber. Results Viscoat® showed significantly higher endothelium coverage compared with both Healon® and DisCoVisc®. A statistically larger volume of Healon5® remained in the anterior chamber compared with Healon® and DisCoVisc®. Conclusion The new evaluation methods used here provide precise quantitative analysis of OAE ratio and residual OVD volume. These results show that Viscoat® and Healon5® have a high potential for coating the corneal endothelium during phacoemulsification and aspiration surgery.

Fibrillin-1, tropoelastin, fibulin-5, and latent transforming growth factor beta-binding protein-2 and protein-4 (LTBP-2 and LTBP-4) are essential proteins for the elastic lamina (EL). In this study, we analyzed each of these molecules in the EL of Bruch’s membrane (BM) through development and aging. C57BL/6 mice (embryonic (E) days E12.5, E15.5, and E18.5; postnatal (P) days P1, P4, and P7 and P3, P6, and P75 weeks of age) were used. To investigate localization, immunohistochemical staining (IH) was performed. Transmission electron microscopy (TEM) was used to evaluate the formation of microfibrils and tropoelastin. mRNA expression was determined by quantitative real-time PCR (qRT-PCR). All five proteins were expressed in the EL of BM by IH except in embryonic mice. TEM results showed that tropoelastin co-stained with microfibrils. Between 3 and 6 weeks of age, microfibrils became longer and thicker. It was difficult to evaluate the EL of BM in senile mice at 75 weeks of age because of abundant deposits which correspond to drusen. mRNA levels of each protein increased dramatically from E15.5 to P1 days and plateaued by P3 weeks as shown by qRT-PCR. In conclusion, these five proteins are possibly involved in elastic fiber assembly in BM. We define the date of full assembly of the EL of BM as 3 weeks of age in mice.

This study aimed to investigate the differences between images obtained by optical coherence tomography angiography (OCTA) with those from immunohistochemical labeling of laser-induced choroidal neovascularization (CNV) in a mouse model. CNV was induced by laser photocoagulation (GYC-2000, NIDEK; wavelength 532 nm) in the left eyes of 10 female C57BL/6J mice aged 6 weeks. The laser parameters included a 100-μm spot, 100-ms pulse duration and 200-mW incident power to rupture Bruch's membrane. OCT and OCTA CNV images were obtained using the RS-3000 Advance (NIDEK) 5 days post-laser photocoagulation. After OCTA imaging, the isolated choroid/retinal pigment epithelium complexes were fluorescently labeled with CD31 (an endothelial cell marker), platelet-derived growth factor receptor β (PDGFRβ, a pericyte-like scaffold marker), α-smooth muscle actin (α-SMA) and collagen I. Area measurements of the lesions obtained by enface OCTA were compared with immunolabeled CD31+ CNV lesions in choroid flat-mounts. We also examined structural correlations between the PDGFRβ+ pericyte-like scaffold and OCTA images. Laser-induced CNV was clearly detected by enface OCTA, appearing as a hyperflow lesion surrounded by a dark halo. Area measurements of the CNV lesion by immunolabeling were significantly larger than those obtained by enface OCTA (p = 0.006). The CNV lesion beneath the periphery of the pericyte-like scaffold was not clearly visible by enface OCTA due to the dark halo; however, the lesion was detectable as blood flow by cross-sectional OCTA and was also highly labeled by CD31. The periphery of the pericyte-like scaffold appeared to develop into subretinal fibrosis and this region was rich in myofibroblasts. Enface OCTA was unable to detect the entire area of laser-induced CNV in mice, with an undetectable portion located beneath the fibrotic periphery of the pericyte-like scaffold. Due to this OCTA fibrosis artifact, OCTA imaging has limited potential for accurately estimating CNV lesions.

Juvenile xanthogranuloma (JXG) is a rare and benign tumor in infants. A solitary lesion on the eyelid has been reported in patients with JXG. We report a 15-year-old boy with multiple involvement of JXG on both eyelids. A mass on the left inner canthus was resected because of disturbance of the visual field and a risk of malignancy in terms of central ulceration in the lesion. The mass was examined by light microscopy. The mass had Touton giant cells with a wreath of nuclei surrounded by foamy histiocytes. No malignancy was observed. The mass showed no recurrence after resection.

A process for extraction of SiO 2 from waste colored glasses by alkali fusion using NaOH was investigated. In the present study, glass waste colored bottles of green, blue, brown or black were selected as samples of waste glasses. These colored bottles were qualitatively confirmed to contain elements of Na, Mg, Al, Si, K, Ca, Ti, Mn, Fe and Cu from energy dispersive X-ray spectroscopic analysis. The condition for alkali fusion of NaOH and the waste glasses was optimized, i.e., for each bottle, the composition was NaOH: crushed glass bottle = 90:10 mass%, melting tentperature was 500°C and melting time was 2 h. For each waste colored bottle, the sodium silicate solution was prepared by using the sodium silicate obtained by alkali fusion. After mixing HCl with the obtained sodium silicate solution, Si(OH) 4 was then precipitated by boiling the solution which became to be a very strong acid. After drying the Si(OH) 4 separ ted from the solution, SiO 2 powder with purity of 99.9% was obtained. The yield of 98.3±0.9% for the SiO 2 powder extracted from the bottles was confirmed from quantitative analysis, indicating that the bottles selected in the present study contained about 60 mass% SiO 2 . From the results of yield and purity, the established process was found to have a potential applicability as a recycling process of waste glasses; various utilizations of waste glasses were expected by extracting SiO 2 which is the main component of the glasses.

The dc electrical conductivity of glasses in the system V2O5–Sb–TeO2 prepared by press quenching was studied at temperatures between 303 and 473 K. The composition range of the glass formation region was found to be 10⩽TeO2⩽100 mol%, 0⩽V2O5⩽70 mol%, and 0⩽Sb⩽20 mol%, respectively. The glasses indicated n-type semiconductors from the measurement of thermoelectric power. The dc conductivities at 473 K for the present glasses were determined to be 6.38×10 −6 –7.13×10 −3 S cm −1 , indicating that the conductivity increased with increasing V2O5 concentration. Sb content also contributed to increase the conductivity and decrease activation energy for electrical conduction. A model of redox reaction during melting was proposed and quantitatively explained the reaction between V2O5 and Sb. A glass of composition 70 V 2 O 5 · 20 Sb · 10 TeO 2 (mol%) having a conductivity of 7.13×10 −3 S cm −1 at 473 K was found to be the highest conductive glass among the previous vanadium–tellurite glasses. From the conductivity-temperature relation, it was found that small polaron hopping model was applicable at the temperature above 1 2 Θ D (ΘD : the Debye temperature); the electrical conduction at T> 1 2 Θ D was due to adiabatic small polaron hopping of electrons between vanadium ions for V2O5⩾50 mol%, and non-adiabatic for 30⩽V2O5 2.90×10 −4 cm 2 V −1 s −1 at 473 K. The carrier density was obtained to be of the order of 10 20 –10 21 cm −3 , and temperature dependence of the carrier density was barely present between 423 and 473 K. The conductivity of the present glasses was primarily determined by hopping carrier mobility.

We report on the experimental results of frequency dependent a.c. conductivity and dielectric constant of SrTiO 3 doped 90V 2 O 5 –10Bi 2 O 3 semiconducting oxide glasses for wide ranges of frequency (500–10 4 Hz) and temperature (80–400 K). These glasses show very large dielectric constants (10 2 –10 4 ) compared with that of the pure base glass (≈10 2 ) without SrTiO 3 and exhibit Debye-type dielectric relaxation behavior. The increase in dielectric constant is considered to be due to the formation of microcrystals of SrTiO 3 and TiO 2 in the glass matrix. These glasses are n-type semiconductors as observed from the measurements of the thermoelectric power. Unlike many vanadate glasses, Long's overlapping large polaron tunnelling (OLPT) model is found to be most appropriate for fitting the experimental conductivity data, while for the undoped V 2 O 5 –Bi 2 O 3 glasses, correlated barrier hopping conduction mechanism is valid. This is due to the change of glass network structure caused by doping base glass with SrTiO 3 . The power law behavior ( σ ac = A ( ω s ) with s x ).

The d.c. conductivity, σ, and the oxygen gas-sensing behaviour of V2O5–SnO–TeO2 glass prepared by press-quenching were studied in argon and oxygen gas atmospheres at temperatures ranging from 303–473 K. The glass of 50V2O5·20SnO·30TeO2 (mol %) was n-type semiconducting. The high-temperature conductivity was lower in oxygen and higher in argon than that in air. This was explained by the V4+ ions in the glass being oxidized by oxygen which had diffused into the glass, resulting in an increase in V5+ with time. The experimental relationship between σ and oxygen partial pressure, P O2, agreed quantitatively with the theoretical relation σ ∝ P O2 -1/4 . Changes in conductivity by switching the atmospheres between oxygen and argon gases were found to be reproducible. From the data of these dynamic changes, the oxygen gas sensitivity, S, at 473 K was obtained to be 1.3 in oxygen atmosphere. The dynamic changes could be quantitatively explained by an oxygen diffusion model. Throughout these discussions, the present tellurite glass was found to possess a potential applicability as an oxygen gas sensor.

The oxygen gas-sensing behavior, as measured by the d.c. conductivity σ, of 62.3V 2 O 5 ·4.3Sb 2 O 3 ·33.3TeO 2 glass (mol%) prepared by press-quenching was studied in Ar and O 2 gas atmospheres at temperatures between 303 and 473 K. The glass was n-type semiconducting. The conductivity was lower in O 2 and higher in Ar than that in air. The explanation for this was that V 4+ ions in the glass were oxidized by the O 2 gas which had diffused into the glass, resulting in an increase in V 5+ with time. The experimental relationship between σ and the oxygen partial pressure P O 2 agreed quantitatively with the theoretical relation σα P O 2 −1/4 . Variations in conductivity on switching the atmospheres between O 2 and Ar gases were found to be reproducible, and the O 2 gas sensitivity S at 473 K was found to be 1.2. These dynamic changes could be explained quantitatively by an oxygen diffusion model. From discussions on the gas-sensing behavior, the present glass was revealed to be potentially applicable as an O 2 gas sensor.

The thermoelectric power of glasses in the systems V2O5-Sb2O3-TeO2 and V2O5-Bi2O3-TeO2 was measured at temperatures in the range 373–473 K. The glasses in both systems were found to be n-type semiconductors. The Seebeck coefficient, Q, at 473 K was determined as −192 to −151 μVK−1 for V2O5-Sb2O3-TeO2 glasses, and −391 to −202 μVK−1 for V2O5-Bi2O3-TeO2 glasses. For these glasses in both systems, Heikes' formula was satisfied adequately for the relationship between Q and In [C v/(1-Cv)] (C v = V4+/Vtotal, C v is the ratio of the concentration of reduced vanadium ions), and discussions confirmed small polaron hopping conduction of the glasses in both systems. Mackenzie's formula relating to Q and V5+/V4+ was also applicable to the glasses in both systems, and it was concluded that the dominant factor determining Q was C v.

The d.c. conductivity (σ) of V2O5-SnO-TeO2 glasses prepared by the press-quenching method was studied at temperatures from room temperature (RT) to 473 K, and the effect of annealing on σ was investigated. The conductivity of 50V2O5·20SnO·30TeO2 glass was determined to be 3.98×10−4 Scm−1 at 473 K and was unchanged for annealing (6–48 h) at 493 K, lower than Tg = 501 K, while its density increased with annealing time. These glasses were found to be n-type semiconductors, and the conduction was confirmed to be due to adiabatic small polaron hopping for V2O5 ≧ 50 mol%, and non-adiabatic for V2O5 < 50 mol%. The activation energy for conduction, W, decreased with annealing time. Variations in oxygen molar volume of the glasses with annealing time inferred a change in glass structure, from loosely to closely packed, resulting in a decrease in vanadium ion spacing with annealing. This caused an increase in the polaron band width, producing a decrease in polaron hopping energy and W. The effect of annealing time on the density of 50V2O5·20SnO·30TeO2 glass was explained adequately by Winter's formula.

The dc conductivity of glasses in the V2O5SnOTeO2 system was studied at temperatures between 200 and 473 K. At temperatures from room temperature (RT) to 200 K, a T − 1 4 (T is temperature) dependence of the conductivity was found, and variable-range hopping conduction was confirmed for these glasses. Mott parameters analysis gave the density of states at the Fermi level, N(EF) = 7.33 × 1019−8.45 × 1020cm−3 eV−1 at 230 K, and N(EF) increased with increasing V2O5 content (V2O5 = 40–50 mol%). At RT, variable-range hopping conduction was observed, which was attributable to large values of the disorder energy of the glasses, WD (= 0.08–0.09 eV), dominating the conduction.

An experimental stuty has been made to investigate the supercooling solidification of aqueous binary solutions. NaCl aqueous solutions of 0.0 to 22.4wt% in concentration were utilized as the testing solutions. Temperature variations have been measured during solidification, and the shape of growing ice has been observed under microscope for three cases of cooling direction (sidewise, bottom and top cooling). Solidification processes could be clarified into several steps: 1) rapid growth of a number of needle-shaped crystal, 2) melting of the top of needles, 3) at the same time, growing of thin and dense dendrides of which front is parallel to the cold plate, 4) coalescence of both fronts, and 5) stationary growing of dendrites. By the use of the box-counting method, it has been confirmed that the stationary growing dendritic ice patterns are fractals with a property of self-similarity, and their value of fractal dimension D has been obtained as 1.77 for sidewise growth dendrites, which was almost independent of the concentration c. In contrast to this case, smaller values of D were given in the case of upward growth and decreased with increasing c. These difference of D between the sidewise and the upward growth was attributable to the natural convection due to the gravity.

The dc electrical conductivity, σ, of 60V2O5⋅10ZnO⋅30TeO2 glass (mol%) prepared by press-quenching was measured under Ar and O2 gas atmospheres and oxygen gas-sensing properties were investigated at temperatures ranging from 303 to 473K. Sigma at 443K in 100% Ar was determined to be 8.53×10-4S·cm-1, which was higher than σ in air (σ443K=7.82×10-4S·cm-1), while σ443K in 100% O2 gas was 3.57×10-4S·cm-1, lower than the σ value in air. This means that V4+ ions in the glass were oxdized by O2 gas which diffused into the glass, resulting in an increase in V5+ with time. The experimental relationship between σ and oxygen partial pressure PO2 agreed well with the theoretical relation σ ∝ PO2-1/4. From data of dynamic change O2 gas sensitivity, S, defined as the ratio of dcresistivity in Ar gas to that in O2 gas, at 473K was obtained to be 1.3 under 100% O2 gas. Changes in σ by switching between 100% O2 and 100% Ar were found to be reproducible. These changes were explained by the oxygen diffusion and desorption model. Good agreements was found between calculated σ and the experimental σ-t relationship. From these discussions, it is concluded that the present tellurite glass has a potential applicability to O2 gas sensor.

The dc conductivity of ternary V 2 O 5 Sb 2 O 3 TeO 2 glasses was studied from room temperature to 473 K. The structure of these glasses was found to become more open with increasing in TeO 2 content based upon calculation of oxygen molar volume. The glasses were found to be n-type semiconductors with conductivity of σ = 2.63 × 10 −6 to 1.46 × 10 −3 S cm −1 at 473 K for 11–62 mol% V 2 O 5 . The conduction was confirmed to be due to small polaron hopping between vanadium ions and was adiabatic for V 2 O 5 > 50 mol% and non-adiabatic for V 2 O 5 J = 0.02 to 0.11 eV which depended on the VV spacing. The carrier concentration was evaluated to be the order of 10 21 cm −3 . Estimated carrier mobility was from 10 −7 to 10 −5 cm 2 V −1 s −1 and varied significantly with V 2 O 5 content. The dominant factor determining conductivity was mobility in these glasses.

The thermoelectric power of semiconducting V2O5-SnO-TeO2 glasses was measured from 373 to 473K. XV2O5⋅10SnO⋅(90-X)TeO2 (X=20 to 60mol%) and XV2O5⋅20SnO⋅(80-X)TeO2 glasses (X=30 to 50mol%) were found to be n-type semiconductors, while 20V2O5⋅20SnO⋅60TeO2 glass, was p-type. The Seebeck coefficient, Q, were determined to be from -188 to +5μV/K at 473K. For n-type semiconducting glasses, Q satisfied the Heikes relation, giving an evidence for small polaron hopping conduction. The Seebeck coefficient for XV2O5⋅20SnO⋅(80-X)TeO2 (X=20-60mol%) and XV2O5⋅10SnO⋅(90-X)TeO2 glasses (X=20-50mol%) increased with decreasing V2O5 content. It is concluded that the dominant factor affecting See-beck coefficient was the fraction of reduced ion concentration, CV(=V4+/Vtotal).

The dc electrical conductivity of annealed V2O5-Sb2O3-TeO2 glasses prepared by quenching was studied. In the high temperature range from room temperature to 473K, conduction of annealed glasses was confirmed to be due to small polaron hopping. An increase in annealing time increased the glass density, and decreased the oxygen molar volume, resulting in a decrease in mean V-ion spacing. This decrease also caused an increase in polaron band width, and a decrease in hopping energy, WH. At temperatures lower than room temperature, the relationship between log σ and T-1/4 was linear. The conductivity analysis based on Mott's variable-range hopping (VRH) theory gave disorder energy, WD=0.06-0.08 eV (at 250K), the density of the states, N(EF)=1.26×1021-9.30×1022cm-3⋅eV-1 (at 250K) and the mean distance in VRH, RVRH=(5.26-19.31)×10-1nm (at 250K). The fact that VRH takes place at such a high temperature as T=243-293K was explained by relatively large WD.

The dc conductivity of V2O5-Bi2O3-TeO2 glasses prepared by press-quenching was studied at temperatures from RT to 473K and the mechanism of conduction was discussed. The glasses were found to be n-type semiconductors and gave the conductivities of 6.6×10-6-3.0×10-4S⋅cm-1 at 473K, activation energies of 0.42-0.53eV for V2O5=30-69mol%. The conduction was confirmed to be due to small polaron hopping and was adiabatic for V2O5>50mol% and non-adiabatic for V2O5

Glasses in the system of V2O5-ZnO-TeO2 glasses were prepared by rapid quenching and their dc-condutivity was studied. A large glass formation region was found i.e., ZnO=0-60mol%, V2O5=0-70mol%, TeO2=30-100mol%. The glasses were found to be n-type semiconductors. Dc-conductivities (σ) were in the range from 9.5×10-7 to 5.7×10-7S⋅cm-1 at 473K for V2O5=30-60mol%. The conduction was due to adiabatic small polaron hopping and non-adiabatic small polaron hopping for the glasses with V2O5>50 and V2O5

Thermally stable, thin W2N, TaN and TaC diffusion barrier layers between Cu and Si were developed by a radio-frequency sputter-deposition technique. The W2N(8 nm), TaN(8 nm) and TaC(5 nm) barrier layers were found to prevent the Cu diffusion to Si after annealing at 600, 700 and 600 °C for 30 min, respectively. These barrier layers have potential as diffusion barrier layers used in ULSI devices. Diffusion mechanism of Cu in Si was studied by using by x-ray diffraction and high-resolution electron microscopy.