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Faricimab is a bispecific antibody that acts through dual inhibition of both angiopoietin-2 and vascular endothelial growth factor A. We report primary results of two phase 3 trials evaluating intravitreal faricimab with extension up to every 16 weeks for neovascular age-related macular degeneration (nAMD).TENAYA and LUCERNE were randomised, double-masked, non-inferiority trials across 271 sites worldwide. Treatment-naive patients with nAMD aged 50 years or older were randomly assigned (1:1) to intravitreal faricimab 6·0 mg up to every 16 weeks, based on protocol-defined disease activity assessments at weeks 20 and 24, or aflibercept 2·0 mg every 8 weeks. Randomisation was performed through an interactive voice or web-based response system using a stratified permuted block randomisation method. Patients, investigators, those assessing outcomes, and the funder were masked to group assignments. The primary endpoint was mean change in best-corrected visual acuity (BCVA) from baseline averaged over weeks 40, 44, and 48 (prespecified non-inferiority margin of four letters), in the intention-to-treat population. Safety analyses included patients who received at least one dose of study treatment. These trials are registered with ClinicalTrials.gov (TENAYA NCT03823287 and LUCERNE NCT03823300).Across the two trials, 1329 patients were randomly assigned between Feb 19 and Nov 19, 2019 (TENAYA n=334 faricimab and n=337 aflibercept), and between March 11 and Nov 1, 2019 (LUCERNE n=331 faricimab and n=327 aflibercept). BCVA change from baseline with faricimab was non-inferior to aflibercept in both TENAYA (adjusted mean change 5·8 letters [95% CI 4·6 to 7·1] and 5·1 letters [3·9 to 6·4]; treatment difference 0·7 letters [-1·1 to 2·5]) and LUCERNE (6·6 letters [5·3 to 7·8] and 6·6 letters [5·3 to 7·8]; treatment difference 0·0 letters [-1·7 to 1·8]). Rates of ocular adverse events were comparable between faricimab and aflibercept (TENAYA n=121 [36·3%] vs n=128 [38·1%], and LUCERNE n=133 [40·2%] vs n=118 [36·2%]).Visual benefits with faricimab given at up to 16-week intervals demonstrates its potential to meaningfully extend the time between treatments with sustained efficacy, thereby reducing treatment burden in patients with nAMD.F Hoffmann-La Roche.

Purpose To develop consensus terminology in the setting of polypoidal choroidal vasculopathy (PCV), and to develop and validate a set of diagnostic criteria not requiring indocyanine green angiograph (ICGA) for differentiating PCV from typical neovascular age-related macular degeneration (nAMD) based on a combination of OCT and color fundus photograph findings. Design Evaluation of diagnostic test Participants Panel of retina specialists. Methods As part of the Asia-Pacific Ocular Imaging Society (APOIS), an international group of experts surveyed and discussed the published literature regarding the current nomenclature and lesion components for PCV and proposed an updated consensus nomenclature, which reflects our latest understanding based on imaging and histology reports. The workgroup evaluated a set of diagnostic features based on OCT and color fundus photographs for PCV that may distinguish it from typical nAMD and assessed the performance of individual and combinations of these non-ICGA features, aiming to propose a new set of diagnostic criteria which does not require the use of ICGA. The final recommendation was validated in 80 eyes from 2 additional cohorts. Main Outcome Measures A consensus nomenclature system for PCV lesion components and non-ICGA-based criteria to differentiate PCV from typical nAMD. Results The workgroup recommended the terms ‘polypoidal lesion’ and ‘branching neovascular network’ for the two key lesion components in PCV. For the diagnosis of PCV, the combination of 3 OCT-based ‘major criteria’ (sub-RPE ring-like lesion, enface OCT complex RPE elevation, and sharp-peaked PED) achieved an area under the receiver operating characteristic curve of 0.90. Validation of this new scheme in a separate subset 110 eyes achieved an accuracy of 82%. Conclusions We propose updated terminology for PCV lesion components which better reflect the nature of these lesions which was based on international consensus. A set of practical diagnostic criteria that are easily applied to SD-OCT can be used for diagnosing PCV with high accuracy in clinical settings in which ICGA is not routinely performed.

Deep eutectic solvents (DESs), a new type of cost-effective ionic liquid analogues, were employed to develop a novel and efficient method for direct functionalization of multiwalled carbon nanotubes (MWNTs) via Diels-Alder (DA) click reaction. Poly(ionic liquid)s featuring furfuryl moieties (P(F-ILs)) and butyl moieties (P(B-ILs)) were synthesized by the functionalization of poly(chloromethylstyrene-alt-maleic anhydride) with 1-methylimidazole and furfuryl amine or butylamine. Then, the polymer was directly grafted on the surface of untreated MWNTs in choline:ethylene glycol (ChCl:EG) based DES without any catalyst. The successful functionalization of the polymer on MWNTs was confirmed by Raman spectroscopy, TGA, and XPS analysis. It was shown that the reaction proceeded in a very rapid fashion (less than an hour) and the use of DESs significantly improved the grafting density (more than double) as compared with the reaction in water.

Polypoidal choroidal vasculopathy (PCV) is an age-related macular degeneration (AMD) subtype and is seen particularly in Asians. Previous studies have suggested disparity in response to intravitreal injections of anti–vascular endothelial growth factor (VEGF) agents between PCV and typical AMD, and thus, the preferred treatment for PCV has remained unclear. Recent research has provided novel insights into the pathogenesis of PCV, and imaging studies based on OCT suggest that PCV belongs to a spectrum of conditions characterized by pachychoroid, in which disturbance in the choroidal circulation seems to be central to its pathogenesis. Advances in imaging, including enhanced depth imaging, swept-source OCT, en face OCT, and OCT angiography, have facilitated the diagnosis of PCV. Importantly, 2 large, multicenter randomized clinical trials evaluating the safety and efficacy of anti-VEGF monotherapy and combination with photodynamic therapy (PDT) recently reported initial first-year outcomes, providing level I evidence to guide clinicians in choosing the most appropriate therapy for PCV. In this review, we summarize the latest updates in the epidemiologic features, pathogenesis, and advances in imaging and treatment trials, with a focus on the most recent key clinical trials. Finally, we propose current management guidelines and recommendations to help clinicians manage patients with PCV. Remaining gaps in current understanding of PCV, such as significance of polyp closure, high recurrence rate, and heterogeneity within PCV, are highlighted where further research is needed.

The compatibility and hydrolytic behaviors of the monolayer mixtures of biodegradable stereochemical polylactide (l-PLA or dl-PLA) and poly(butylene succinate) (PBS) were studied by the Langmuir technique at the air/water interface. The π-A behaviors of two binary systems, well mixed and unmixed, were compared with each other to demonstrate their compatibility. From the changes in the occupied area and the transition region, the compatibility of l-PLA/PBS monolayer mixtures decreased with increasing PBS composition while dl-PLA/PBS monolayer mixtures showed better compatibility than l-PLA/PBS monolayer mixtures. Since PBS monolayers at a pH of 6.8 showed a long transition region of approximately 5 mN/m due to the conformation change, the change in the PBS transition in the monolayer mixtures was analyzed. The results were in accordance with the occupied area. The hydrolytic behaviors of the homopolymer and mixed monolayers on an alkaline subphase were monitored at a constant surface pressure as a function of exposure time. The compatible monolayer mixtures showed much slower hydrolytic kinetics than their arithmetic averages. This hydrolytic impedance is mainly due to the interaction between both monolayer chains which prevents the ions from attacking the ester bonds of PBS, resulting in a much faster hydrolytic rate than that of PLA.

In this study, low bandgap polymers containing a monofluoroquinoxaline (FQx) or a difluoroquinoxaline (DFQx) as the electron-deficient unit and 2-thiophenylbenzo[1,2-b:4,5-b']dithiophene as the electron-rich unit were synthesized by Stille polymerization. The polymers exhibit satisfactory thermal stability and a broad absorption band from 300 to 650 nm. The HOMO/LUMO energy levels of PB-FQx and PB-DFQx were − 5.62/− 3.64 and − 5.70/− 3.63 eV, respectively. We found that for a high number of fluorine atoms in the conjugated backbone, the HOMO energy levels were deeper, which led to increased VOC. The PB-DFQx:ITIC-based PSC exhibited the best power conversion efficiency of 6.31%, with its VOC of 0.99 V, JSC of 10.61 mA/cm2, FF of 60%.

Purpose: To evaluate the safety and efficacy of dexamethasone intravitreal implant (Ozurdex, DEX implant) 0.7 and 0.35 mg in the treatment of patients with diabetic macular edema (DME).Design: Two randomized, multicenter, masked, sham-controlled, phase III clinical trials with identical protocols were conducted. Data were pooled for analysis.Participants: Patients (n = 1048) with DME, best-corrected visual acuity (BCVA) of 20/50 to 20/200 Snellen equivalent, and central retinal thickness (CRT) of ≥300 μm by optical coherence tomography.Methods: Patients were randomized in a 1:1:1 ratio to study treatment with DEX implant 0.7 mg, DEX implant 0.35 mg, or sham procedure and followed for 3 years (or 39 months for patients treated at month 36) at ≤40 scheduled visits. Patients who met retreatment eligibility criteria could be retreated no more often than every 6 months.Main Outcome Measures: The predefined primary efficacy endpoint for the United States Food and Drug Administration was achievement of ≥15-letter improvement in BCVA from baseline at study end. Safety measures included adverse events and intraocular pressure (IOP).Results: Mean number of treatments received over 3 years was 4.1, 4.4, and 3.3 with DEX implant 0.7 mg, DEX implant 0.35 mg, and sham, respectively. The percentage of patients with ≥15-letter improvement in BCVA from baseline at study end was greater with DEX implant 0.7 mg (22.2%) and DEX implant 0.35 mg (18.4%) than sham (12.0%; P ≤ 0.018). Mean average reduction in CRT from baseline was greater with DEX implant 0.7 mg (−111.6 μm) and DEX implant 0.35 mg (−107.9 μm) than sham (−41.9 μm; P < 0.001). Rates of cataract-related adverse events in phakic eyes were 67.9%, 64.1%, and 20.4% in the DEX implant 0.7 mg, DEX implant 0.35 mg, and sham groups, respectively. Increases in IOP were usually controlled with medication or no therapy; only 2 patients (0.6%) in the DEX implant 0.7 mg group and 1 (0.3%) in the DEX implant 0.35 mg group required trabeculectomy.Conclusions: The DEX implant 0.7 mg and 0.35 mg met the primary efficacy endpoint for improvement in BCVA. The safety profile was acceptable and consistent with previous reports.

Purpose To describe the findings of enhanced depth imaging (EDI) optical coherence tomography (OCT) of the lamina cribrosa (LC) in glaucoma and pachychoroid spectrum diseases associated with peripapillary retinoschisis. Design Retrospective, observational case series. Participants A total of 16 patients from 1 institution. Methods Detailed medical case histories, optic disc and retinal imaging with EDI using the Spectralis OCT (Heidelberg Engineering, Heidelberg, Germany), and clinical course were reviewed for patients with peripapillary retinoschisis without a known predisposing condition. Main Outcome Measures Clinical features and findings of the EDI OCT. Results Among the 16 eyes with peripapillary retinoschisis that had abnormal findings on EDI of the LC, 8 had glaucoma and 8 had pachychoroid spectrum diseases, including chronic central serous chorioretinopathy (CSC) (6 eyes), small pigment epithelium detachment (1 eye), and polypoidal choroidal vasculopathy (PCV) (1 eye). The abnormal LC findings were central or peripheral focal LC defects in eyes with glaucoma and LC disinsertions or peripheral focal LC defects in eyes with pachychoroid spectrum diseases. Central LC defects were related to inner layer retinoschisis, whereas LC disinsertions and peripheral LC defects were related to outer layer retinoschisis. The peripapillary retinoschisis did not show a topographic association with the underlying chronic CSC- or PCV-associated lesions. In 6 treated eyes with pachychoroid, peripapillary retinoschisis resolved along with subretinal fluid after anti–vascular endothelial growth factor injection in 4 eyes, whereas retinoschisis persisted after the resolution of subretinal fluid in 2 eyes. Conclusions Enhanced depth imaging OCT of the LC demonstrated alterations associated with peripapillary retinoschisis, pachychoroid spectrum diseases, and glaucoma.

Age-related macular degeneration (AMD) is the leading cause of irreversible blindness in elderly people globally. It is estimated that there will be more Asians with AMD than the rest of the world combined by 2050. In Asian populations, polypoidal choroidal vasculopathy (PCV) is a common subtype of exudative AMD, while choroidal neovascularization secondary to AMD (CNV-AMD) is the typical subtype in Western populations. The two subtypes share many common clinical features and risk factors, but also have different epidemiological and clinical characteristics, natural history and treatment outcomes that point to distinct pathophysiological processes. Recent research in the fields of genetics, proteomics and imaging has provided further clarification of differences between PCV and CNV-AMD. Importantly, these differences have manifested as disparity in response to intravitreal injections of anti-vascular endothelial growth factor (anti-VEGF) treatment between PCV and CNV-AMD, emphasizing the need for accurate diagnosis of PCV and in distinguishing PCV from CNV-AMD, particularly in Asian patients. Current clinical trials of intravitreal anti-VEGF therapy and photodynamic therapy will provide clearer perspectives of evidence-based management of PCV and may lead to paradigm shifts in therapeutic strategies away from those currently employed in the treatment of CNV-AMD. Further research is needed to clarify the relative contribution of specific pathways in inflammation, complement activation, extracellular matrix dysregulation, lipid metabolism and angiogenesis to the pathogenesis of PCV. Findings from this research, together with improved diagnostic technology and new therapeutics, will facilitate more optimal management of Asian AMD.

Objective The primary study hypothesis was that ranibizumab 0.5 mg monotherapy or combined with laser is superior to laser monotherapy based on mean average change in best-corrected visual acuity (BCVA) over 12 months in Asian patients with visual impairment resulting from diabetic macular edema (DME). Design A 12-month, randomized, double-masked, multicenter, laser-controlled, phase III study. Participants Three hundred ninety-six patients aged ≥18 years, with type 1 or 2 diabetes mellitus, BCVA of 78–39 Early Treatment Diabetic Retinopathy Study (ETDRS) letters, and visual impairment resulting from DME. Methods Patients were randomized to ranibizumab + sham laser (n = 133), ranibizumab + active laser (n = 132), or sham injection + active laser (n = 131). Ranibizumab/sham injections were administered on day 1 and continued monthly. As of month 3, monthly injections were continued if stable vision was not reached. Treatment was reinitiated if BCVA decreased because of DME progression. Active/sham laser was administered on day 1 and thereafter according to ETDRS guidelines. Main Outcome Measures Average change in BCVA from baseline to months 1 through 12, central retinal subfield thickness (CRST), and safety over 12 months. Results Ranibizumab monotherapy or combined with laser was superior to laser in improving mean average change in BCVA from baseline to months 1 through 12 (+5.9 and +5.7 vs +1.4 letters). At month 12, greater proportion of patients gained ≥15 letters with ranibizumab and ranibizumab + laser compared with laser (18.8% and 17.8% vs 7.8%). Mean CRST reduced significantly from baseline to month 12 with ranibizumab (−134.6 μm) and ranibizumab + laser (−171.8 μm) versus laser (−57.2 μm). Patients received a mean of 7.8 and 7.0 ranibizumab injections in the ranibizumab and ranibizumab + laser arms, respectively, and 1.5–1.9 active laser across treatment arms over 12 months. Conjunctival hemorrhage was the most common ocular, whereas nasopharyngitis and hypertension were the most common nonocular adverse events. Ranibizumab was not associated with any cases of cerebrovascular hemorrhage and cerebrovascular ischemia. No death related to study treatment was reported. Conclusions Ranibizumab monotherapy or combined with laser showed superior BCVA improvements over laser treatment alone in Asian patients with visual impairment resulting from DME. No new ocular or nonocular safety findings were observed and treatment was well tolerated over 12 months.

To examine the correlation between estimated intravaginal ejaculatory latency time (eIELT) and stopwatch-measured intravaginal ejaculatory latency time (sIELT), and to assess the clinical utility of eIELT in identifying men more likely to have lifelong premature ejaculation (PE).A prospective, observational, multicenter study was conducted. Between July 2010 and August 2011, 118 healthy men aged 30-70 years, more likely to have lifelong PE, were recruited from 5 institutions in Korea. All patients underwent preliminary assessments including collection of medical and sexual history, physical examination, determination of eIELT, and the Premature Ejaculation Profile questionnaire. During the 1-week study period, patients were requested to engage in sexual intercourse at least twice and to record the sIELT.eIELT and sIELT correlated well (r = 0.512; P .001). However, eIELT was overestimated by a mean of 1.2 ± 0.2 minutes (median, 1.0 minutes) compared with sIELT (P = .046). eIELT showed a reduced correlation with the Premature Ejaculation Profile measures, compared with sIELT (each P-value .05). The diagnostic accuracy of eIELT was 67.9% (P = .001), and an eIELT of 2 minutes was the acceptable cutoff value to diagnose lifelong PE.Although eIELT correlated well with sIELT, it was overestimated by approximately 1 minute and had lower clinical utility than sIELT. Our study suggests that eIELT and sIELT cannot be directly interchanged and that caution should be used when substituting sIELT with eIELT to identify men who are more likely to have lifelong PE.

Purpose To investigate the influence of photodynamic therapy (PDT) and combination of PDT and ranibizumab on aqueous humor levels of vascular endothelial growth factor (VEGF) in polypoidal choroidal vasculopathy (PCV). Design Prospective randomized clinical trial. Method We included 20 eyes with treatment-naive PCV and 20 eyes undergoing cataract surgery as controls. PCV eyes were randomized to treatment with PDT alone or to a combination of ranibizumab and PDT on the same day. During 3 months, retreatment was not performed. Aqueous humors were collected at baseline and at 1 week, 1 month, and 3 months after treatment in the PCV group and during cataract surgery in the control group. VEGF levels were measured using multiplex bead immunoassay. Results At baseline, VEGF levels were significantly increased in PCV eyes compared with control eyes. A significant decrease in VEGF levels was found at 1 week after PDT treatment (n = 8) and at all time points after combination treatment (n = 12). With combination treatment, VEGF levels were decreased to values below the detection limit in all eyes at 1 week and 1 month and in 7 of 12 eyes at 3 months. There was no difference in the clinical profiles among the 2 treatment groups at each time point. Conclusion Decreased levels of VEGF detected 1 week after PDT for PCV seems to reflect acute damage of vascular endothelial cells, one of the VEGF expression sites in PCV. Concomitant ranibizumab resulted in a further decrease in VEGF to negligible levels, but this result did not affect the clinical results for 3 months.

The multi-walled carbon nanotube was introduced into the polymer matrix (PANI) to improve the electric conductivity as well as mechanical properties of the original polymer matrix. PANI/multi-walled carbon nanotube (MWCNT) composites were synthesized via ex-situ and in-situ polymerization to improve their electrical property. And the DC conductivities of PANI/MWCNT according to content and diameter of MWCNT were measured by four-point probe. The highest electric conductivity of PANI/MWCNT composite is 20 S/cm when 0.3% (mass fraction) MWCNTs with 10 nm in diameter and 15 μm in length are added in composite.

The contribution of ciliary muscle to the development and progression of myopia has been addressed. A thickened ciliary muscle in myopia has been speculated as an internal equatorial growth restriction, possibly a matter of hypertrophy with potentially poor contractility, which may result in the development and progression of myopia. In this preliminary study, we evaluated the interrelationship of ciliary muscle characteristics and myopia in 31 volunteers (aged 19–35), via ultrasound biomicroscope (UBM), with eyes focused on far and near targets. Univariate and multivariate regression analysis (using stepwise variable selection) were employed to analyze the relationship between axial length/refractive error and various parameters of ciliary muscle (CM)–cross-sectional area (CMA); length from scleral (CMLs) and vitreous (CMLv) aspects; thickness at 1.0 mm (CMT1), 2.0 mm (CMT2), and 3.0 mm (CMT3) posterior to scleral spur; maximum thickness (CMTm); and apical angle. The impact on accommodation of changes (Δ) in above parameters and of centroid variations was subsequently assessed. In a univariate analysis, axial length showed positive relationship with CMLs (r = 0.454, p = 0.017) and CMT3 (r = 0.460, p = 0.018), and negative relationship with ΔCMTm (r = −0.501, p = 0.008) and Δapical angle (r = −0.400, p = 0.039). Multivariate regression analysis showed that ΔCMTm (β = −0.506, p = 0.008) was independently related with axial length. A negative correlation between CMTm and ΔCMTm was also observed (r = −0.432, p = 0.024). These results suggest that accentuated ciliary muscle thickness, suggesting muscular hypertrophy, may account for the inherent dysfunction in myopia. Further studies are necessary to confirm these preliminary observations and hypotheses.

In the present investigation, we evaluated the acute changes in intraocular cytokines after intravitreal injection of an anti-vascular endothelial growth factor (VEGF) in diabetic retinopathy (DR). This analysis may contribute to the understanding of changes in intraocular cytokines after intravitreal bevacizumab (IVB), which is frequently used to reduce permeability and neovascularization in DR. This study was a prospective, open-label, controlled, randomized clinical trial. Eyes of 30 consecutive patients who were scheduled for pars plana vitrectomy (PPV) for proliferative DR (PDR) were prospectively enrolled. All patients were randomly assigned to receive IVB either at 1 (group 1) or 7 (group 2) days before PPV, and aqueous humor samples were taken from the anterior chamber just prior to IVB and PPV. The levels of VEGF, interleukin (IL)-2, IL-6, IL-8, tumor necrosis factor (TNF)-α, and transforming growth factor-β(2) (TGF-β(2)) in aqueous humor were evaluated at each time point-baseline and after IVB. VEGF levels were significantly decreased at day 1 (p=0.003) and the decrease sustained through day 7 (p=0.004). IL-6 increased from 23.26 ± 26.68 to 1992.88 ± 2266.87 pg/mL at day 1 (p

The silylation of plasma-damaged p-SiOCH low-k dielectric films was investigated with trimethychlorosilane (TMCS), hexamethyldisilazane (HMDS) and dimethyldichlorosilane (DMDCS) dissolved in supercritical CO"2 (scCO"2) and the effect of thermal pre-treatment on the repair performance was also studied. The surface hydrophobicity was rapidly recovered by silylation and the order of recovery efficiency was HMDS (85.4^o)>DMDCS (83.4^o)>TMCS (75.0^o). The FTIR analyses revealed that the restoration to the original state was not achieved over various reaction conditions (up to 31MPa, 85^oC, and 3h reaction time). After pre-treatment in a vacuum cell at 250^oC, the Si-O-Si peak intensity increased slightly, and the surface hydrophobicity was partially recovered to 54.4^o due to the removal of physically adsorbed H"2O molecules as well as some extent of dehydration of neighboring surface silanol groups. The hydrophobicity increased to 84.4^o after subsequent treatment with HMDS in scCO"2. From DSIMS, the carbon concentration did not increase in bulk region after silylation of thermally pre-treated low-k films.

The emulsion polymerization of vinyl acetate monomer (VAM), ethylene and N-methylol acrylamide (NMA) was carried out in a high pressure stirred reactor using an Rushton flat blade impeller at a rotational speed of 300 rpm under a semi-batch polymerization process, which was subsequently grown by the continuous addition of monomers (VAM, ethylene, and NMA). The particle diameters of the samples withdrawn during polymerization were determined by using capillary hydrodynamic fractionation (CHDF). Also, the number of particles was calculated from the data obtained by CHDF. Coagulum formation was studied. It was found that coagulum formation increased with increasing conversion and auto-accelerated from ca. 20% conversion. The definition of coagulum in this research was presented. The coagulum formation pattern on the impeller was shown. Also, the flow pattern in the reactor under the same geometrical configuration and operating conditions was simulated.

When macroscopic crystalline monomers were polymerized by a free-radical solid-state reaction in the presence of supercritical CO 2 (scCO 2 ), the resultant products were found to be composed of unexpected nanoparticle morphologies. In particular, the solid-state polymerization (SSP) of amino acid based monomers, acryloyl-β-alanine (ABA) and methacryloyl-β-alanine (MBA), initiated by azobisisobutyronitrile in scCO 2 (at 65 °C and 34.5 MPa), produced corresponding polymers having aggregated spherical architectures. The average diameters of the PABA and PMBA particles were measured to be 94 and 102 nm, respectively. In addition, high molecular weight polymers (PMBA, M w = 3.8 × 10 5 g/mol) with a high yield (∼96%) were obtained. The microscopic investigation revealed that a unique particle formation mechanism was involved in the SSP in which large sized crystalline monomers were chipped into small pieces during the initial stage of polymerization and subsequently converted into nanoscale objects after 24 h.

A transparent and antistatic coating material consisting of polymer core-metal shell particle was prepared. As a polymer core, poly(butylacrylate-co-styrene)s ([P(BA-co-sty)s]) with various compositions of butylacrylate and styrene were synthesized by emulsion polymerization. And the effect of comonomer composition on the thermal property of polymer core particle was investigated. By electroless plating method, the nickel particles were formed and deposited on the surface of P(BA-co-Sty) particles to form P(BA-co-Sty) core-nickel shell composite particles. SEM observation confirms that the nickel particles with size of 15 nm are distributed on the surface of the polymer core particles. The surface resistance of P(BA-co-Sty) core-nickel shell composite is 0.8×10 8 Ω/cm 2 , enough to act as antistatic coating material.

We prepared poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) nanofibers by the electrospinning method and applied to the polymer matrix in polymer electrolytes for dye-sensitized solar cells (DSSCs). The uptake, ionic conductivity, and porosity of the electrospun PVDF-HFP nanofiber films showed 653±50%, 4.53±1.3×10−3 S/cm, and 70±2.3%, respectively, regardless of the diameter and morphology of nanofibers. In addition, several DSSC devices using the electrospun PVDF-HFP nanofiber films as the polymer matrix were prepared to investigate the photovoltaic effect of iodine (I2) concentrations on DSSC devices. With an increase of I2 concentration in electrolyte solutions, the ionic conductivity increased, while the photocurrent density of DSSC devices decreased.

Morphological changes of solution-grown crystals (SGCs) of poly(l-lactide) (PLLA) following thermal treatment and enzymatic degradation were investigated using atomic force microscopy in terms of defects in the crystals. PLLA SGCs were grown from a dilute solution of acetonitrile at 5 degrees C. The obtained solution-grown monolamellar crystals have a lozenge-shaped morphology containing unique dimensions, with one side measuring 12 microm. To investigate enzymatic degradation behavior, PLLA SGCs were incubated in buffered solution with proteinase-K at 37 degrees C. The initial stage of enzymatic degradation of PLLA SGCs with proteinase-K occurs in loosely folding chains at the surface of the crystal. Thermally treated PLLA SGCs below the melting temperature showed an increase of the lamellar thickness of the SGCs at the treated temperature and partial surface erosion following enzyme exposure. These results indicate that less ordered chains exist throughout the lamellae and their thermal-induced chain extension makes them more susceptible to enzyme attack.

Porous hydroxyapatite (HAp)/chitosan-alginate composite scaffolds containing different amounts (0, 10, and 30 wt.%) of HAp were successfully synthesized by in-situ co-precipitation method. It was found that the pore structure of the composite scaffolds was similar to chitosan-alginate scaffolds, and the morphology of uniform microstructure was unaffected by the presence of HAp. However, the pore diameter decreased with increasing the HAp content up to 30 wt.%, eventually the pore structure was collapsed and appeared to be agglomerated. The compressive strength of the HAp/chitosan-alginate composite scaffolds increased with increasing of the HAp content.

Fiber morphology and crystalline structure of poly[(R)-3-hydroxybutyrate] (P(3HB)) and stereocomplexed poly(lactide) (PLA) nanofibers were investigated by using scanning and transmission electron microscopies and X-ray and electron diffractions. In the P(3HB) nanofibers spun from less than 1 wt% 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) solution, planar zigzag conformation (beta-form) as well as 2(1) helix conformation (alpha-form) structure was formed. Based on the electron diffraction measurement of single P(3HB) nanofiber, it was revealed that the molecular chains of P(3HB) align parallel to the fiber direction. From the enzymatic degradation test of P(3HB) nanofiber, it was shown that beta-form molecular chains are degraded more preferentially than alpha-form chains. Stereocomplexed PLA nanofibers were electrospun from 1 wt% poly(l-lactide)/poly(d-lactide) (PLLA/PDLA) solution in HFIP, which contains equal amounts of PLLA and PDLA. While as-spun stereocomplexed PLA nanofiber was amorphous, PLA nanofiber annealed at 100 degrees C contained only racemic crystal. It was supposed that the crystallization behavior of stereocomplexed PLA in the nanofiber is affected by the electrospinning process, which forcibly exerts the strain onto the polymer chains.

The degradation kinetics of Langmuir monolayer films of a series of biodegradable polyesters has been studied to investigate the effect of degradation medium, alkalinity and enzymes. The degradation behavior of polyester monolayers strongly depended on both degradation medium and surface pressure. As the surface pressure was increased, the degradation rates of poly( l -lactide) (PLLA) and poly[(R)-3-hydroxybutyrate] (P(3HB)) increased in both degradation media. When monolayers were exposed to an alkaline subphase, the degradation of PLLA monolayers occurred at relatively low surface pressures; the PLLA monolayers were hydrolyzed at pH 10.5 regardless of surface pressure, while the alkaline degradation of P(3HB) monolayer occurred over a constant surface pressure of 7 mN/m at pH 11.8. These results have been explained by the difference in hydrophilic/hydrophobic balance of the polymers; PLLA is more hydrophilic than P(3HB). In contrast, the enzymatic degradations of both polymer monolayers occurred at higher constant surface pressures than those of the alkaline treatment; 7 mN/m for PLLA and 10 mN/m for P(3HB). This behavior was attributed to the enzymes being much larger than the alkaline ions: the enzymes need a larger contact area with the submerged monolayers to be activated.

Various random copolymers of poly(poly(ethylene glycol) methacrylate-co-1H,1H,2H,2H-perfluorooctylmethacrylate) (p(PEGMA-co-FOMA)) with different poly(ethylene glycol) (PEG) chain length (Mn = 300, 475, and 1100) and different FOMA content have been synthesized in supercritical carbon dioxide (scCO2) via free-radical polymerization. The copolymers containing above 50 wt% FOMA could be used as a stabilizer for the polymerization of methyl methacrylate (MMA) in scCO2. For PEGMA (300) and PEGMA (475) copolymers, the copolymeric stabilizer with 67–69 wt% FOMA content was shown to be optimal to produce micrometer-size spherical PMMA powder. The size of pendant PEG group and the composition of copolymer as well as the concentration of MMA affected on the size of PMMA particles and the stability of PMMA latexes in CO2.

Ring-opening suspension polymerization of l -lactide in supercritical CO 2 (scCO 2 ) was investigated in the presence of different stabilizer architectures based on poly(dimethyl siloxanes) (PDMS). Two amphiphilic AB type block copolymers, a graft copolymer, and an ester-capped PDMS were selected to find their efficacy as stabilizers for the synthesis of poly( l -lactide) (PLLA) in scCO 2 . The stabilizer’s efficiency was analyzed in terms of the molecular weight, yield, and particle morphology of PLLA. The block copolymers, poly(dimethylsiloxane)- b -poly(acrylic acid) (PDMS- b -PAA) and poly(dimethylsiloxane)- b -poly(methacrylic acid) (PDMS- b -PMA) were found to be effective, leading to the formation of fine, discrete PLLA microparticles. On the other hand, the graft copolymer, poly(dimethylsiloxane- g -pyrrolidonecarboxylic acid) (PDMS- g -PCA) and acetylated PDMS (PDMS-OAc) failed to give an enough stabilization to the PLLA due to their short polymer-philic chains, resulting in hard agglomerates.

The hydrolytic behavior of monolayers of enantiomeric poly(lactide)s (PLAs), d-PLA and l-PLA, and their mixtures spread at the air/water interface has been studied in order to elucidate the hydrolytic stability on the stereocomplex formation of enantiomeric components. The rate of hydrolysis was recorded by a change of occupied area when the monolayer is maintained at a constant surface pressure. Under a basic subphase, the hydrolysis of the (d-PLA/l-PLA 50/50 by mol.%) mixture monolayer was much slower than those of each homopolymer. This result suggests that the stereocomplexed monolayer is more hydrolysis-resistant than each homopolymer one.

An oriented morphology has been generated by shear aligning a triblock copolymer SIS below its order–disorder transition (ODT) temperature. Elongational flow deformation was conducted on a polystyrene-block–polyisoprene-block–polystyrene (SIS) triblock copolymer having soft spherical microdomains composed of polyisoprene block chains in a hard matrix of polystyrene block chains with extensional rheometer (RME). The triblock copolymer has an equilibrium microphase-separated morphology of spheres (body centered cubic, BCC) of polystyrene in a polyisoprene matrix. The evolving structure was investigated with rheology, transmission electron microscopy (TEM) and small angle X-ray scattering (SAXS). The structure related to various condition of elongational flow deformation has been determined from SAXS patterns by considering separately changes in the single particle scattering, which influence the scattering patterns. The TEM and SAXS data of the film samples show that the spherical PS-domain was deformed and reoriented along the direction of elongation. It was found that the spheres microdomains are transformed into cylinder microstructures with short-range order.

γ-Cyclodextrin (γ-CyD) was hydrophobically modified by selective functionalization at the C-6 position (primary face) with fluoroalkyl ester groups. This new amphiphilic γ-CyD was prepared in a facile one-pot synthesis by direct esterification of γ-CyD with perfluorobutanoic acid on the narrow rim of macrocylic molecule. The selective per-substituted product, octakis (6-O-perfluorobutanoyl)-γ-cyclodextrin (γ-CyD-F), was confirmed by 1H NMR, 13C NMR and 19F NMR spectroscopic methods. The complexing ability of the γ-CyD-F was investigated with different types of anionic surfactant having single or double hydrophobic tail groups. Predominant complex formation was observed in all cases with an equimolar mixture of surfactant and γ-CyD-F in methanol irrespective of the type of the surfactant.

Scanning force microscopy was applied for the study of the surface morphology and mechanical properties of (poly(methyl acrylate)/poly(methyl methacrylate) 95/5 by wt) (PMA/PMMA) blend film. X-ray photoelectron spectroscopy (XPS), lateral force microscopy (LFM), and scanning viscoelasticity microscopy (SVM) measurements of the phase-separated PMA/PMMA blend film were carried out to evaluate the effect of surface roughness on the surface composition. It was revealed that the surface composition of the blend film measured by XPS was much higher than that by LFM or SVM. The remarkable difference of the surface composition between XPS and LFM measurements was explained by the surface roughness of the blend film because LFM and SVM only reflect the surface physical properties of the material, regardless of the surface roughness.

The effects of addition of non-degradable polymers on the rate of enzymatic erosion for the poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] have been studied at 37 °C and pH 7.4 in the aqueous solution of an extracellular PHB depolymerase from Alcaligenes facalis. Polystyrene (PS) or poly(methyl methacrylate) (PMMA) was selected as a minor component (5 wt%) in a blend because of their non-enzymatic activity. Enzymatic degradation behaviors of the “as-cast” and “annealed” blend films were investigated using atomic force microscopy and weight loss measurements. Although the spherulites of P(3HB-co-3HV) cover all blend film surfaces throughout, the retardation of biodegradation in the P(3HB-co-3HV)/PS blend films was detected from morphological observation and weight loss measurement for both as-cast and annealed blend films while there was little difference between the P(3HB-co-3HV)/PMMA blend and pure P(3HB-co-3HV). Since the enzymatic degradation of P(3HB-co-3HV) initially occurs by a surface erosion process, these degradation behaviors were explained by the surface structure of blend films measured by X-ray photoelectron spectroscopy. The surface of P(3HB-co-3HV)/PS blend films revealed an excess of PS, whereas the surface of P(3HB-co-3HV)/PMMA blend films was nearly covered by P(3HB-co-3HV). It was concluded, therefore, that the PS, which exists within P(3HB-co-3HV) spherulites at surface acts as a retardant of enzymatic attack to the surface of the blend film.

The relationship between glass transition temperature (Tg) and lateral force of amorphous polymer blends composed of components having Tg's lower and higher than room temperature (295 K) was studied on the basis of lateral force microscopy (LFM). Although the lateral force for the homopolymer is deeply related to its surface viscoelastic property or Tg, the LFM results revealed that the lateral force dependence on the scan rate of the miscible polymer blends, [poly(methylacrylate)/poly(vinylacetate)] and [polystyrene/poly(vinylmethylether)], was similar with that of the component whose lateral force behavior shows the dependence on the scan rate, regardless of their Tg. This result suggests that the lateral force of miscible polymer blend reflects the sum of each component contribution, depending on the surface structure of the blend. Therefore, it was concluded that the information about surface structure can be obtained from the measured lateral force behavior of a miscible polymer blend.

In this work, fracture toughness and properties of blends of plasticized poly(vinyl chloride) (PVC) and thermoplastic polyurethane (TPU) were investigated. Two kinds of TPU with different hardness, i.e. TPU90 (Shore A hardness 90) and TPU70 (Shore A hardness 70) were compared. PVC/TPU90 and PVC/TPU70 blends with variable weight ratio ( 100 0 , 90 10 , 80 20 , 70 30 , 60 40 , 50 50 , 0 100 ) were prepared by melt blending. Fracture toughness was investigated using the J-integral by locus method. Blending of TPU with plasticized PVC improved tensile strength, impact strength, abrasion resistance, and thermal stability, with small decline of tensile modulus and hardness. The PVC/TPU blends showed flame retardancy over the composition ranges, regardless of the hardness of TPU, except the PVC/TPU70 of 50 50 composition, in terms of the limiting oxygen index. PVC/TPU70 blends showed higher Jc values and thus higher fracture toughness over the entire composition than PVC/TPU90 blends. For the PVC/TPU70 blends, the SEM micrographs showed clear dimple rupture fracture topology, while the PVC/TPU90 blends did not.

The surface morphology of annealed bilayer films, thin poly(methyl acrylate) (PMA) and/or polystyrene (PS) films on poly(vinylidene fluoride) (PVDF) thick film, was studied on the basis of X-ray photoelectron spectroscopy and atomic force microscopy. Although the surface free energy values for PS and PMA are close, the surface morphology of annealed bilayer films are fairly different due to the difference in the interaction parameter between components of the bilayer film. Ater annealing at above the melting temperature of PVDF, top-layer PMA which is miscible with PVDF in the melt was gradually remixed with bottom-layer PVDF across all the interface, whereas the dewetting of top-layer PS was observed in (PS/PVDF) bilayer film due to the immiscibility and the surface free energy difference beteen PVDF with PS. However, the surface concentration of PVDF was in the order (PMA/PVDF)>[(PMA/PS) mixture/PVDF)] bilayer films under the same annealing condition. This result was explained in terms of the intermolecular interaction, the surface free energy and the competition between wetting and remixing processes.

In this work, hydrolysis of biodegradable poly( l -lactide) ( l -PLA) and copolymers of l -lactide ( l -LA) and (benzyloxycarbonyl) methyl mophorline-2,5-dione (BMD) was investigated at the air/water interface. In order to improve the hydrophilicity of l -PLA, small amounts of BMD were copolymerized with l -LA. NaOH was used to adjust the pH of the subphase water. Under the conditions studied here, polymer monolayers showed much faster hydrolysis as either a subphase pH or the concentration of BMD in the copolymer is increased. This result was explained by increasing numbers of base attack sites per unit area and increasing hydrophilicity.

The surface enrichment of blend films of poly(methyl methacrylate) (PMMA) and poly(vinyl acetate) (PVAc) cast from various solvents has been investigated by contact angle, X-ray photoelectron spectroscopic and attenuated total reflection Fourier transform infra-red spectroscopic measurements. The composition of each component was fixed at 50 wt%. The surfaces of miscible PMMA/PVAc blend films are found to be enriched in PVAc regardless of casting solvents. It was found that the surface enrichment of PVAc in the PMMA/PVAc blend is reduced when the as-cast blend film shows phase separation or when the phase-mixed blend is heated above the lower critical solution temperature and exhibits thermally induced phase separation.

The compatibilizing effect of a new graft copolymer of poly(ethylene glycol) (PEG) on nylon 6 (nylon 6-g-PEG) was investigated for nylon 6 poly(vinyl acetate) (PVAc) blends by using melting-point depression and X-ray diffractograms. It was found that nylon 6-g-PEG exhibits no compatibilizing effect for the nylon 6 PVAc blends, but the graft copolymer itself shows a miscibility window in its blends with PVAc for blend compositions containing less than 50 wt% of the graft copolymer.

A 71-year-old man presented with decreased vision and red eye in his left eye that had lasted for 1 month. He was diagnosed as HIV-positive 2 years previously and had received highly active antiretroviral therapy (HAART). Visual acuity was hand motion only, and conjunctival injection and chemosis were noted (fi gure, A). A fundus examination showed prominent vitritis, and sectorial haemorrhagic retinitis in the superonasal periphery, which was much the same as viral retinitis (fi gure, B). After 5 days, the visual acuity had decreased to light perception, and the retinal lesion had enlarged and was protruding (fi gure, C). A viral PCR of the aqueous humour was negative. The patient’s CD4 cell count was 377 cells per μL. Rapid plasma reagin and fl uorescent treponemal antibody absorbed tests of the serum were positive. 5 days after intravenous penicillin G was given, the infl ammatory reaction substantially improved (fi gure, D, E). At 6 months, the eye had no infl ammation, and the patient’s vision was 20/50 (fi gure, F). His CD4 cell count was 517 cells per μL, and the patient’s condition was stable without any complications. Ocular syphilis is known as a great imitator and does not have a pathognomonic ocular feature. It can involve the entire ocular section, and its clinical manifestations can include scleritis, iritis, chorioretinitis, and optic neuritis. Retinitis in patients infected with HIV can be associated with various ocular infections such as viral retinitis, toxoplasmosis, and syphilis. Delayed diagnosis and treatment of retinitis can lead to permanent visual impairment. Clinical manifestations and the immune status of the patient can provide clues to help with the diff erential diagnosis. Cytomegalovirus retinitis, which is the most common opportunistic infection in the HIV population despite HAART, usually develops in quiet eyes (those with a clear cornea without redness or irritation of the conjunctiva or sclera) with lower CD4 cell counts. In our patient, severe scleritis was a characteristic presenting sign distinguishable from cytomegalovirus retinitis. The possibility of ocular syphilis should be considered in a diff erential diagnosis of retinitis in an infl amed red eye in HIV-positive patients receiving HAART, to ensure early diagnosis and treatment.

In this work, organic electroluminescent devices (OELDs) were fabricated using fluorine-containing polyimide as a matrix polymer to hole transporting layer. The device consists of indium tin oxide (ITO) coated glass/triphenyl diamine derivative (TPD)-dispersed polyimide/Alq3/Al structure. The effect of the molecular structure of both the polyimides containing fluorine atoms or having no fluorine atoms on the device performances was investigated.

Purpose To compare clinical outcomes after vitrectomy and internal limiting membrane (ILM) peeling, with and without gas tamponade, for the treatment of myopic foveoschisis. Design Retrospective, comparative, interventional case series. Methods In this retrospective clinical study, 17 eyes of 17 consecutive patients underwent vitrectomy and ILM peeling for treatment of myopic foveoschisis. Eyes were divided into 2 groups, those with gas tamponade (n = 9) and those without (n = 8). Gas tamponade was chosen according to the period and surgeon's discretion. The changes of foveal anatomy on preoperative optical coherence tomography (OCT) were not considered in the decision. Main outcome measures were the rate of resolution of myopic foveoschisis measured by OCT, the time interval until resolution of myopic foveoschisis, central foveal thickness, and best-corrected visual acuity (BCVA). Results After surgery, OCT showed a resolution of myopic foveoschisis in 8 eyes (88.9%) in the gas-treated group and in 6 eyes (75.0%) in the no-gas group. This difference between the groups was statistically insignificant (P = .576). The mean period until the resolution of myopic foveoschisis was 2.25 months in the gas-treated group and 4.50 months in the no-gas group (P = .011). The mean BCVA improved significantly in both the gas-treated and no-gas groups (P = .011 and P = .017, respectively). Conclusions Vitrectomy and ILM peeling without gas tamponade appears to be as effective in the treatment of myopic foveoschisis as vitrectomy with gas tamponade. However, eyes treated with gas tamponade showed more rapid resolution of myopic foveoschisis.