Wafer-scale integration of GaAs/AlGaAs core-shell nanowires on silicon by the single process of self-catalyzed molecular beam epitaxy.

GaAs/AlGaAs core-shell nanowires, typically having 250 nm diameter and 6 µm length, were grown on 2-inch Si wafers by the single process of molecular beam epitaxy using constituent Ga-induced self-catalysed vapor-liquid-solid growth. The growth was carried out without specific pre-treatment such as film deposition, patterning, and etching. The outermost Al-rich AlGaAs shells form a native oxide surface protection layer, which provides efficient passivation with elongated carrier lifetime. The 2-inch Si substrate sample exhibits a dark-colored feature due to the light absorption of the nanowires where the reflectance in the visible wavelengths is less than 2%. Homogeneous and optically luminescent and adsorptive GaAs-related core-shell nanowires were prepared over the wafer, showing the prospect for large-volume III-V heterostructure devices available with this approach as complementary device technologies for integration with silicon.

Effect of trabeculectomy on corneal endothelial cell loss.

AIM: To investigate changes in corneal endothelial cell density (CECD) after trabeculectomy. METHODS: This prospective, observational study followed 117 eyes of 117 patients for 2 years after trabeculectomy. The central cornea was examined by corneal specular microscopy prior to and at every 6 months after the surgery. Survival analysis of patients who exhibited a 10% or less reduction of the postoperative CECD compared with preoperative levels was assessed using the Kaplan-Meier survival curve. A Cox proportional hazards model was used to evaluate prognostic factors for decreasing CECD. RESULTS: At baseline, the mean CECD was 2420±357 cells/mm2, while at 6, 12, 18 and 24 months after surgery, the mean CECD was 2324±373 cells/mm2 (p<0.001), 2276±400 cells/mm2 (p<0.001), 2290±398 cells/mm2 (p<0.001) and 2267±446 cells/mm2 (p<0.001), respectively. At 6, 12, 18 and 24 months after surgery, the results of the Kaplan-Meier survival analysis of the 10% loss of CECD from baseline were 91%, 85%, 83% and 77%, respectively. Uveitic glaucoma was a significant prognostic factor for decreasing CECD (p=0.041). CONCLUSIONS: CECD significantly and continuously decreased after trabeculectomy.

Influence of Disc Size on the Diagnostic Accuracy of Cirrus Spectral-Domain Optical Coherence Tomography in Glaucoma.

PURPOSE: To examine the influence of optic disc size on the diagnostic accuracy of optic nerve head (ONH) parameters determined by Cirrus spectral-domain optical coherence tomography (Cirrus HD-OCT). METHODS: A total of 51 eyes of 51 normal participants and 71 eyes of 71 glaucoma patients were examined. ONH imaging was obtained by Cirrus HD-OCT. Sensitivity at a fixed 90% specificity along with the area under the receiver operating characteristic curve (AUC) for continuous parameters were analyzed. We also examined the coefficients of variation (CoV) for sensitivity estimates, as these have been used to test and quantify the influence of optic disc size on diagnostic accuracy. The influence of optic disc size on the glaucoma diagnosis was assessed by the likelihood ratio chi-square test. RESULTS: Among the continuous parameters, the best diagnostic accuracy was seen for the average rim area, which had an AUC of 0.96. The most reliable factor across the disc size groups was the rim area (CoV, 2.8%). The diagnostic accuracy of the rim area did not appear to be influenced by optic disc size (P = 0.17). CONCLUSIONS: The high diagnostic accuracy of the rim area demonstrated by Cirrus HD-OCT for the quantitative assessment of the ONH was not significantly affected by disc size in this study.

Electrical Matching at Metal/Molecule Contacts for Efficient Heterogeneous Charge Transfer.

In a metal/molecule hybrid system, unavoidable electrical mismatch exists between metal continuum states and frontier molecular orbitals. This causes energy loss in the electron conduction across the metal/molecule interface. For efficient use of energy in a metal/molecule hybrid system, it is necessary to control interfacial electronic structures. Here we demonstrate that electrical matching between a gold substrate and π-conjugated molecular wires can be obtained by using monatomic foreign metal interlayers, which can change the degree of d-π* back-donation at metal/anchor contacts. This interfacial control leads to energy level alignment between the Fermi level of the metal electrode and conduction molecular orbitals, resulting in resonant electron conduction in the metal/molecule hybrid system. When this method is applied to molecule-modified electrocatalysts, the heterogeneous electrochemical reaction rate is considerably improved with significant suppression of energy loss at the internal electron conduction.

Retinal oxygen saturation before and after glaucoma surgery.

PURPOSE: This study compared retinal vessel oxygen saturation before and after glaucoma surgery. METHODS: Retinal oxygen saturation in glaucoma patients was measured using a non-invasive spectrophotometric retinal oximeter. Adequate image quality was found in 49 of the 108 consecutive glaucoma patients recruited, with 30 undergoing trabeculectomy, 11 EX-PRESS and eight trabeculotomy. Retinal oxygen saturation measurements in the retinal arterioles and venules were performed at 1 day prior to and at approximately 10 days after surgery. Statistical analysis was performed using a Student's t-test. RESULTS: After glaucoma surgery, intraocular pressure (IOP) decreased from 19.8 ± 7.7 mmHg to 9.0 ± 5.7 mmHg (p < 0.001). Although oxygen saturation in retinal arterioles remained unchanged before and after surgery (104.7 ± 10.6% before and 105.4 ± 9.3% after surgery, p = 0.58), the oxygen saturation in the venules increased from 54.9 ± 7.4% to 57.4 ± 5.7% (p = 0.01). CONCLUSION: Intraocular pressure (IOP) decreases caused by glaucoma surgery had an effect on the retinal venous oxygen saturation.

Additive Intraocular Pressure Lowering Effects of the Rho Kinase Inhibitor, Ripasudil in Glaucoma Patients Not Able to Obtain Adequate Control After Other Maximal Tolerated Medical Therapy.

INTRODUCTION: The aim of this study is to investigate the additive intraocular pressure (IOP)-lowering effects and safety of the selective Rho kinase inhibitor, 0.4% ripasudil, in patients with glaucoma not adequately controlled by other maximal tolerated medical therapies. METHODS: We retrospectively reviewed 92 glaucoma patients who received ripasudil as an additive glaucoma treatment. In spite of receiving prior maximal tolerated medical therapies, all patients had uncontrolled glaucoma before receiving ripasudil. IOP was recorded at all follow-up dates. RESULTS: The study population consisted of 43 primary open-angle glaucoma (POAG), 28 normal-tension glaucoma (NTG), ten secondary glaucoma, seven exfoliation glaucoma, and four developmental glaucoma patients. After ripasudil administration, there was a significant decrease in the IOP. The mean pre-administration IOP and % IOP reduction at the last follow-up were 19.7 ± 4.9 mmHg and 6.5 ± 17.0% for POAG, 15.5 ± 2.0 mmHg and 2.3 ± 10.4% for NTG, 22.8 ± 8.3 mmHg and 19.1 ± 13.5% for secondary glaucoma, 22.5 ± 4.4 mmHg and 2.1 ± 14.5% for exfoliation glaucoma, and 20.2 ± 8.9 mmHg and 11.4 ± 23.1% for developmental glaucoma, respectively. Side effects led to ripasudil discontinuation in 13 patients, with five exhibiting an allergic reaction, six developing blepharitis, and two having a burning sensation. CONCLUSIONS: Use of ripasudil as an adjunctive therapy resulted in lowering of the IOP. Ripasudil was well tolerated. FUNDING: Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science, and Technology of Japan (26462689).

Relationship between oxygen saturation of the retinal vessels and visual field defect in glaucoma patients: comparison with each hemifield.

PURPOSE: This study aimed to elucidate the relationship between visual field defects in the upper and lower hemifields and the corresponding oxygen saturation of the retinal vessels in patients with glaucoma. METHODS: Patients with glaucoma (n = 44) exhibiting more than a 10 dB difference between the upper and lower total deviation (TD) were enrolled in the study. After measuring the retinal vessel oxygen saturation by a non-invasive spectrophotometric retinal oximeter, the hemifields in one eye of each patient were divided into worse (worse TD) and better (better TD) hemifield areas. We additionally evaluated a separate group of 40 patients with glaucoma who exhibited less than a 5 dB difference between the upper and lower TD. Statistical analysis was performed using a Student's t-test. RESULTS: A higher mean venous saturation of oxygen (SaO2 ) was observed in the worse (59.0 ± 8.0%) hemifield compared to the better (55.4 ± 7.2%) hemifield (p < 0.01). The mean arteriovenous difference in the SaO2 was lower in the worse (44.4 ± 9.0%) hemifield compared to the better (48.6 ± 11.4%) hemifield (p = 0.02). However, when we evaluated the worse and better hemifields in the patients who had less than a 5 dB difference in the upper and lower hemifield TD, we found no statistically significant differences for either the retinal SaO2 in the venous vessels or the arteriovenous difference. CONCLUSIONS: Advanced glaucomatous visual field defects were associated with increased SaO2 in the venous vessels and a decreased arteriovenous difference in the SaO2 . The present results suggest there is a reduced retinal oxygen extraction in eyes with glaucomatous damage due to retinal ganglion cell loss.

Comparison of Macular Integrity Assessment (MAIA ™), MP-3, and the Humphrey Field Analyzer in the Evaluation of the Relationship between the Structure and Function of the Macula.

PURPOSE: This study was conducted in order to compare relationships between the macular visual field (VF) mean sensitivity measured by MAIATM (Macular Integrity Assessment), MP-3, or Humphry field analyzer (HFA) and the ganglion cell and inner plexiform layer (GCA) thicknesses. METHODS: This cross-sectional study examined 73 glaucoma patients and 19 normal subjects. All subjects underwent measurements for GCA thickness by Cirrus HD-OCT and static threshold perimetry using MAIATM, MP-3, or HFA. VF and OCT in the retinal view were used to examine both the global relationship between the VF sensitivity and GCA thickness, and the superior hemiretina and inferior hemiretina. The relationship between the GCA thickness and macular sensitivity was examined by Spearman correlation analysis. RESULTS: For each instrument, statistically significant macular VF sensitivity (dB) and GCA thickness relationships were observed using the decibel scale (R = 0.547-0.687, all P < 0.001). The highest correlation for the global (R = 0.682) and the superior hemiretina (R = 0.594) GCA thickness-VF mean sensitivity was observed by the HFA. The highest correlation for the inferior hemiretina (R = 0.687) GCA thickness-VF mean sensitivity was observed by the MP-3. Among the three VF measurement instruments, however, no significant differences were found for the structure-function relationships. CONCLUSIONS: All three VF measurement instruments found similar structure-function relationships in the central VF.

The Relationship Between Vision-related Quality of Life and Visual Function in Glaucoma Patients.

PURPOSE: To evaluate the relationship between vision-related quality of life (QOL) as measured by the short-form 11-item Japanese version of the Visual Function Questionnaire (VFQ-J11) and the severity of visual field (VF) defects in patients with glaucoma. METHODS: The study included 134 glaucoma patients and 30 normal subjects. VF testing using the Humphrey Field Analyzer was performed to obtain both the VF index (VFI) and MD in both eyes of each glaucoma patient. Binocular integrated VF was constructed for each patient by merging corresponding sensitivity values from monocular VFs, and the correlation between visual function and vision-related QOL was then assessed. RESULTS: A significant relationship was found between QOL and VF in 6 of 7 subscales on the VFQ-J11, and between the composite scores in both the better eye and the worse eye in glaucoma patients. The relationship was stronger in the worse eye than in the better eye. Overall, correlation coefficients of the VFI were higher than those of MD and slightly higher than those of integrated VF in the worse eye. CONCLUSIONS: The VFI showed a marginally better correlation than MD. Assessment of VFI in the worse eye may provide useful information regarding vision-related QOL in glaucoma patients.

Use of the structure-function relationship in detecting glaucoma progression in early glaucoma.

BACKGROUND: To evaluate the use of optical coherence tomography (OCT) retinal nerve fiber layer (RNFL) thickness and visual field (VF) measurements in detecting disease progression in patients with early glaucoma. METHODS: Over a 3-year period, this study examined 60 eyes of 39 glaucoma patients whose total deviation in the superior or inferior hemifield was more than -6 dB. All eyes underwent at least four serial RNFL measurements performed by Cirrus OCT, with the first and last measurements separated by at least three years. On the same day as the RNFL imaging, VF testing was also performed by using the Swedish Interactive Threshold Algorithm Standard 30-2 program of the Humphrey Field Analyzer. Serial RNFL thicknesses and VF progression were assessed using the Guided Progression Analysis (GPA) software program. RNFL thickness progression and VF progression were evaluated by the event analysis. RESULTS: The mean observation period was 57.6 ± 10.0 months, and during this time, a total of 366 OCT and 366 VF measurements were performed. Using only OCT, progression was found in 2 eyes, while progression was found in 1 eye when only using VF GPA. When combined measurement findings were used, the analysis found progression in 8 eyes. CONCLUSIONS: When mild VF defect is present, OCT RNFL thickness measurements can be helpful in discerning glaucoma progression.