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Purpose: The proper implantable collamer lens (ICL) size affects ICL stability. This study compared device efficacy using white-to-white diameter (WTW) measurements with Orbscan II and IOL Master 700.Methods: We retrospectively studied 90 eyes (45 patients) who underwent toric ICL implantation from January 2019 to February 2020 and were followed for 1 year. The correlation between WTW and anterior chamber depth (ACD) for each measuring device was analyzed.Results: The mean WTW measured by IOL Master 700 and Orbscan II was 12.2 ± 0.3 and 11.6 ± 0.3 mm, respectively, while the mean ACD was 3.28 ± 0.16 and 3.20 ± 0.15 mm. The WTW and ACD measured with IOL Master 700 averaged 0.57 ± 0.12 and 0.08 ± 0.04 mm larger than with Orbscan II. The differences were significant and the regression analysis had high correlations (R2 = 0.875 and R2 = 0.913, respectively; both p < 0.001).Conclusions: WTW measured by the IOL Master 700 can be used as a reference either alone or together with the Orbscan II value to determine ICL size.

Purpose: We compared 1 year refractive outcomes between combined laser-assisted subepithelial keratomileusis (LASEK) and accelerated collagen cross linking (CXL LASEK), and LASEK alone.Methods: The study was conducted as a retrospective analysis including 166 eyes of 83 moderate myopia patients who underwent CXL LASEK, and 146 eyes of 73 moderate myopia patients underwent LASEK alone. Uncorrected distance visual acuity (UDVA), spherical equivalent (SE), keratometry were evaluated preoperatively, and at 1, 3, and 6 months, and 1 year after surgery.Results: There was significant difference of preoperative SE (p < 0.05), UDVA (p < 0.05). There was no significant difference of preoperative flat K (p = 0.10) and steep K (p = 0.18) between the two groups. At the 1-year follow-up, the SE was ± 0.25 diopter (D) in 80.5% of the CXL LASEK patients and 59.7% of the LASEK patients (p < 0.05). There was significant difference between the SE (p < 0.05), flat K (p = 0.02) and steep K (p = 0.05) rates over time between the two groups. After removing the preoperative results, there was no significant difference between the SE (p = 0.45) over time between the two groups.Conclusions: The postoperative refractive stability of the CXL LASEK group was confirmed.

Purpose: To compare tear film lipid layer thickness (LLT) and dry eye parameters between non-diabetic and diabetic patients after cataract surgery.Methods: We retrospectively studied patients who underwent cataract surgery. We enrolled 65 eyes of 36 patients with cataracts but not diabetes (group I) and 35 eyes of 23 patients with both cataracts and diabetes (group II). The LLT, partial blink rate, tear break-up time (TBUT), and strip meniscometry tests were performed preoperatively and 1 and 2 months after surgery. The ocular surface disease index (OSDI) questionnaire was completed before and 2 months after surgery by both groups.Results: In group I, the strip meniscometry test value was 3.2 ± 1.4 mm before surgery, 2.3 ± 1.0 mm at 1 month, and 2.5 ± 1.0 mm at 2 months, thus significantly less than before surgery (p < 0.05). The TBUT result was 3.4 ± 1.6 seconds before surgery, 3.0 ± 1.5 seconds at 1 month, and 2.9 ± 1.5 seconds at 2 months, thus significantly less than before surgery (p < 0.05). The OSDI score was 30.8 ± 21.3 before surgery and 20.0 ± 15.8 at 2 months, thus significantly lower than before surgery (p < 0.05). In group II, the TBUT decreased significantly from the preoperative value of 3.6 ± 1.3 seconds to 3.0 ± 1.0 seconds at 1 month and 3.1 ± 1.0 seconds at 2 months (p < 0.05). The OSDI score was 30.0 ± 20.6 before surgery and 19.0 ± 16.0 at 2 months, thus significantly lower than before surgery (p < 0.05). Neither group evidenced any significant difference in the LLT before and after surgery.Conclusions: There was a difference in dry eye parameters in each group before and after cataract surgery, but there was no difference between the two groups.

Purpose: Contrast sensitivity, the ability to distinguish the relative difference in luminance of an object from its surrounding or adjacent objects, is a useful measure of visual function. In granular corneal dystrophy type 2 (GCD2), opacity of the corneal stroma causes deterioration in visual function. We compared the contrast sensitivity of GCD2 patients before and after phototherapeutic keratectomy (PTK) to evaluate the perioperative visual function in these patients.Methods: This study included 22 eyes of heterozygote GCD2 patients. The visual acuity and contrast sensitivity were measured before and after PTK. The contrast sensitivity was measured in mesopic and photopic background luminances, with glare (G) levels of 0-2 (G0, G1, and G2, respectively) and spatial frequencies at 1.5, 3, 6, 12, and 18 cycles per degree (cpd).Results: The contrast sensitivity increased after PTK at 1.5 and 3 cpd in mesopic and photopic conditions with G0-2 glare (p < 0.05). At 6 cpd, the contrast sensitivity increased in the mesopic condition with G1 glare, and in the photopic condition with G0-2 glare (p < 0.05). However, there was no change in contrast sensitivity at any glare level at 12 and 18 cpd after PTK.Conclusions: In GCD2 patients, the contrast sensitivity increased significantly after PTK. The vision of GCD2 patients, which is decreased due to corneal opacity, is improved after PTK.

Single-atoms (SAs) with atomically coordinated reaction centers are considered the next generation of catalysts that can exhibit exceptional catalytic efficiency. However, the general concern about thermodynamic vulnerabilities of SAs questions their practical value. Moreover, whether the inherent catalytic nature of SAs is superior compared with that of larger nanoparticles is still under debate. Here, we address two controversies by a comparative study using two catalysts: Pt/TiO2 and Pt/CeOx–TiO2. Based on a hierarchical study of density functional theory, time-resolved catalysis performance test, in situ infrared spectroscopy, and operando X-ray absorption spectroscopy, we could unveil the catalytic nature of Pt-SAs and their stability. By utilizing the heterogeneous interface formed between TiO2 supporting particles and CeOx clusters formed on the surface of TiO2, we preferentially synthesized Pt-SAs pinned at the CeOx–TiO2 interfaces on CeOx–TiO2 hybrid-oxide supports. The strong electronic coupling between the Pt-SAs and the Ce ions at the CeOx–TiO2 interfaces enhanced the catalytic activity toward CO oxidation of Pt-SAs and improved the long-term stability under CO oxidation conditions. The CO oxidation activity of Pt-SAs stabilized at CeOx–TiO2 was improved by 13.5 times at 200 °C compared with the Pt-SAs on TiO2. The results present how to easily improve the activity and stability of Pt-SAs using a simple interface control method. Moreover, we demonstrate that the catalytic activity and the stability of Pt-SAs can be monitored through the chemical state of the interfaces. Our study provides comprehensive understanding about the catalytic nature as well as a novel strategy toward applications of Pt-SAs, enabling sustainable use of Pt in heterogeneous catalysts.

Purpose: To investigate the safety of laser epithelial keratomileusis (LASEK) by drawing a comparison between two groups divided according to age (18-19 vs. 20-21 years old).Methods: The study was conducted as a retrospective analysis including 339 patients (678 eyes) who underwent LASEK between January 2017 and April 2020. Patients were divided by age group, group I (18-19 years old) and group II (20-21 years old). The objectives of the study included determination of visual acuity and refractive errors before and at 1, 3, and 6 months after the procedure.Results: The preoperative mean spherical equivalents (SEs) were -4.73 ± 0.88 diopters (D) in group I and -4.58 ± 0.87 D in group II (p = 0.34). At 1 month postoperatively, mean SEs were 0.32 ± 0.46 D in group I and 0.26 ± 0.59 D in group II (p = 0.18). At 3 months postoperatively, the mean SEs were 0.30 ± 0.47 D in group I and 0.28 ± 0.50 D in group II (p = 0.67). At 6 months postoperatively, the mean SEs were 0.15 ± 0.47 D in group I and 0.14 ± 0.50 D in group II (p = 0.89). There were no significant differences in postoperative best corrected visual acuity between group I and group II at 1, 3, or 6 months (p = 0.20, p = 0.13, and p = 0.11, respectively).Conclusions: There were no significant differences in postoperative mean SE or safety of LASEK between moderate myopia patients 18-19 years old and those 20-21 years old.

A bridge bearing anchor transmits various loads of a superstructure to a substructure. Most anchors are generally designed without consideration of characteristics such as concrete pedestal, grout bedding, and anchor socket. This study investigated the shear behavior of anchors in accordance with the edge distance, embedment depth, compressive strength of concrete, and height of the concrete pedestal in order to simulate the practical characteristics of the bridge bearing anchors. The actual shear capacity of the anchor differs from the shear strengths calculated by the ACI 318 and EN 1992-4; especially, the importance of the embedment depth is underestimated in these codes. An increase in the height of the concrete pedestal has a negative effect on the shear capacity because of the stress concentration. The grout is fractured prior to the occurrence of local damages in concrete, resulting in a secondary moment. As a result, the effect of the level arm is observed. An equation, which can predict the relative cracking degree of concrete, is proposed by analyzing the displacement of grout and concrete. High strain occurs in the stirrups close to the anchor, and the behavior of the strain is more influenced by the embedment depth than the edge distance. The comparison of obtained and analytically evaluated failure loads by calculations according to EN 1992-4, Schmid model and Sharma model was conducted to consider the effect of supplementary reinforcement. Finally, the design equation of concrete breakout strength is modified to predict the more precise shear resistance of a bridge bearing anchor.

Naftopidil (NAF), an α1-adrenoceptor antagonist, is administered as a treatment for benign prostatic hyperplasia; however, according to the Biopharmaceutical Classification System (BCS IV), it is a poorly-soluble drug that exhibits poor permeability. We aimed to increase the dissolution (%) of NAF by adding chitosan to a polymer-free formulation. Compared to the formulation prepared using Flivas®, at 60 min, the solid dispersion (SD) formulation containing NAF, fumaric acid, chitosan, and US2® in a 1:1:2:1 weight ratio improved the dissolution (%) of NAF in distilled water, pH 1.2 media, pH 4.0 and pH 6.8 buffers by 27.2-, 1.2-, 1.1- and 6.5-fold, respectively. The physicochemical properties of the SD1 formulation were also found to be altered, including its thermal properties, crystal intensity, and chemical interaction. As a result, the hydrogen bonding that occurs between NAF and fumaric acid was identified as a major factor in the increase in NAF dissolution (%). Further, chitosan was observed to contribute to the stability of NAF and SD1, which was assessed over a 3-month period. To our knowledge, this is the first study to employ a polymer-free system to improve the solubilization of NAF.

The development of pH-independent drugs is difficult because it involves improvements in their solubility and dissolution (%) in solubilizer. In the present study, the pH-independent cilostazol (CLT) was formulated for enhanced solubility and dissolution (%) and for maintaining stability with meglumine by the solid dispersion (SD) technique. The CLT formulations were prepared with weak acid or weak base by solvent evaporation method. Moreover, the physical properties of the optimal SD formulation that were evaluated were thermal property, crystallinity, and drug-excipient interaction. Based on the pre-dissolution test, meglumine and Aerosil®200 were selected as the weak base and carrier, respectively. The SD1 formulation (CLT:meglumine:Aerosil®200 at 1:1:0.5, w/w) enhanced the dissolution (%) of CLT in distilled water/pH 1.2/pH 6.8 buffer by 1.20-/1.13-/1.18-fold, respectively, compared with those of Pletal®. Moreover, SD1 formulation was stable at room temperature for 3 months. A slight change in the crystallinity of CLT was observed in the SD1 formulation, which may be due to intermolecular interaction between CLT and meglumine. The SD1 formulation showed improved dissolution (%) and might improve the bioavailability and efficacy of CLT.

This study investigates the influence of steel slag (SS) and steel fibers on the electrical resistivity and electromagnetic (EM) shielding effectiveness of high-strength concrete (HSC). It was found that the electrical resistivity of mixtures were mainly influenced by free water. Thus, the EM shielding effectiveness was evaluated without the effect of free water. HSC with 20% replacement ratio of SS exhibited slightly improved EM shielding, lower electrical resistivity, and reduced strength (compressive and flexural) compared to HSC without SS. However, HSC with steel fibers exhibited significantly improved EM shielding, lower electrical resistivity, and higher strength and toughness compared to HSC without steel fibers. An increase in the steel fiber content in the HSC significantly decreased the electrical resistivity and increased the shielding effectiveness, strength, and toughness. Regardless of the fiber content in the fiber volume fraction of mixture, the shielding effectiveness is similar for cases with and without SS whose electrical resistivity values differ only slightly. This proves that the EM shielding effectiveness was mainly affected by the electrical resistivity and these properties are significantly correlated when the electrical resistivity values differ noticeably. HSC reinforced with rebar with 50 mm spacing exhibited a 23.5–75.6% increase in the shielding effectiveness in the 600–1,000 MHz frequency region compared to pristine HSC.

Solubilization studies of tadalafil (TDF) have recently improved the dissolution (%) using weak acids and bases in our group. However, the weak acid formulations have a low dissolution (%) of TDF as limitation. Thus, the purpose of this study was to improve the dissolution (%) of TDF over 90% in distilled water (DW) by weak acid-chitosan based multi-system. The SD formulation (SD11: TDF, tartaric acid, chitosan, Aerosil®200, and PVP/VA S-630 in a 1:2:1:1:2 weight ratio) showed higher dissolution (%) of TDF by 5.0-, 6.0-, and 5.8-fold at 60 min than that of Cialis® in DW and pH 1.2 and pH 6.8 buffers, respectively. The physical properties of the SD11 formulation were changed. Moreover, the SD11 formulation maintained stability for 3 months. In conclusion, the solubilization of TDF using chitosan was successfully performed for the first time.

In this study, the breakout capacity of a single anchor specimen in concrete simulating the bridge bearing connection with the characteristics of reinforcement, anchor socket, bed concrete, and mortar was evaluated for shear. The concrete breakout capacities were compared based on the embedment length of the anchor socket and edge distance, and the difference between the existing design strength and the actual strength was determined, which indicated safety issues. In addition, the shear resistance performance of the effective anchor reinforcement was evaluated through the strain analysis of the reinforcement. Finally, Through the results of this study, a concrete breakout capacity formula that reflects the characteristics of the bridge bearing connection has been proposed.

This study aimed to evaluate the anticancer activity of paclitaxel-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles (PNPs) based on their shapes and surface modifications in breast cancer cells. We hypothesized that anisotropic-PNPs (AT-PNPs) with PEGylated chitosan (CP) surface modifications and high aspect ratios exhibit higher anticancer activity than PNPs and AT-PNPs with CP surface modifications and low aspect ratios. Six types of PNPs and AT-PNPs with different shapes and surface modifications were successfully prepared. The cellular uptake and cytotoxicity of the AT-PNPs were higher than those of the PNPs, while the cellular uptake and cytotoxicity of the PNPs and AT-PNPs with CP were higher than those of the uncoated PNPs and AT-PNPs. Moreover, all the particles remained stable for 4 months. In conclusion, this study primarily described the preparation of CP-AT-PNPs, and the CP-AT-PNPs2 developed herein are expected to demonstrate promising anticancer effects in animal experiments and clinical studies.

Aldehyde-alcohol dehydrogenase (AdhE) is an enzyme responsible for converting acetyl-CoA to ethanol via acetaldehyde using NADH. AdhE is composed of two catalytic domains of aldehyde dehydrogenase (ALDH) and alcohol dehydrogenase (ADH), and forms a spirosome architecture critical for AdhE activity. Here, we present the atomic resolution (3.43 Å) cryo-EM structure of AdhE spirosomes in an extended conformation. The cryo-EM structure shows that AdhE spirosomes undergo a structural transition from compact to extended forms, which may result from cofactor binding. This transition leads to access to a substrate channel between ALDH and ADH active sites. Furthermore, prevention of this structural transition by crosslinking hampers the activity of AdhE, suggesting that the structural transition is important for AdhE activity. This work provides a mechanistic understanding of the regulation mechanisms of AdhE activity via structural transition, and a platform to modulate AdhE activity for developing antibiotics and for facilitating biofuel production., Using cryo-EM, Kim et al. show that aldehyde-alcohol dehydrogenase (AdhE) spirosomes undergo structural transition from compact to extended conformation from substrate binding. This transition opens up the substrate channel that transports the reaction intermediates to the next catalytic site.

We propose an interface-engineered oxide-supported Pt nanoparticle-based catalyst with improved low-temperature activity toward CO oxidation. By wet-impregnating 1 wt % Ce on TiO

We fabricated and characterized AlGaN/GaN high-electron mobility transistors (HEMTs) with a nano-sized in situ cap layer (one is a silicon carbon nitride (SiCN) layer, and the other is a silicon nitride (SiN) layer) comparing to the conventional device without an in situ cap layer. The pulse characteristics and noise behaviors for two devices with in situ cap layers are much superior to those of the reference device without a cap layer, which means that the in situ cap layer effectively passivates the AlGaN surface. On the other hand, the device with an in situ SiCN cap layer showed the excellent device characteristics and noise performances compared to the other devices because of the reduced positive ionic charges and enhanced surface morphology caused by carbon (C) surfactant atoms during the growth of the SiCN cap layer. These results indicate that the AlGaN/GaN HEMT with the in situ SiCN cap layer is very promising for the next high-power device by replacing the conventional HEMT.

Following the fourth Industrial Revolution, electronic and data-based technology is becoming increasingly developed. However, current research on enhancing electromagnetic interference (EMI) shielding and the physical protection performance of structures incorporating these technologies is insufficient. Therefore, in this study aiming for the improvement of EMI shielding and structural performance of structures, twelve concrete walls were fabricated and tested to determine their shielding effectiveness and drop-weight impact resistance. Concrete walls strengthened by three thickness types of high-strength, high-ductility concrete (HSDC) have been considered. The test results showed that the shielding effectiveness with strengthening thickness increased by approximately 35.6–46.2%. Specimens strengthened by more than 40% and 10% of the strengthening area ratio of single- and double-layer, respectively, exhibited more than 20 dB of shielding effectiveness. Moreover, the relationship between the damaged area ratio and shielding effectiveness was evaluated by means of the drop-weight impact test. The structural performance and EMI shielding effectiveness improved as the HSDC thickness increased.

There is increased interest in applying electromagnetic (EM) shielding to prevent EM interference, which destroys electronic circuits. The EM shielding’s performance is closely related to the electrical conductivity and can be improved by incorporating conductive materials. The weight of a structure can be reduced by incorporating lightweight aggregates and replacing the steel rebars with CFRP rebars. In this study, the effects of lightweight coarse aggregate and CFRP rebars on the mechanical and electrical characteristics of concrete were investigated, considering the steel fibers’ incorporation. The lightweight coarse aggregates decreased the density and strength of concrete and increased the electrical conductivity of the concrete, owing to its metallic contents. The steel fibers further increased the electrical conductivity of the lightweight aggregate concrete. These components improved the EM shielding performance, and the steel fibers showed the best performance by increasing shielding effectiveness by at least 23 dB. The CFRP rebars behaved similarly to steel rebars because of their carbon fiber content. When no steel fiber was mixed, the shielding effectiveness increased by approximately 2.8 times with reduced spacing of CFRP rebars. This study demonstrates that lightweight aggregate concrete reinforced with steel fibers exhibits superior mechanical and electrical characteristics for concrete and construction industries.

Highly reactive dense Pt single-atoms stabilized on an oxide support can resolve a grand challenge in the economic use of Pt in catalysis. The maximized number density of reaction sites provided by dense Pt single-atoms guarantees the improved catalytic performance of Pt combined with high efficiency. By manipulating the chemical nature of multi-component interfaces, we synthesized CO-tolerant dense Pt single-atoms highly reactive for the CO oxidation reaction, which governs the key steps for chemical energy conversion and emission control. The addition of 1 wt% of Ce to TiO2 support particles creates a CeOx–TiO2 interface that stabilizes Pt single-atoms by strong electronic interactions. Dense Pt single-atoms formed on CeOx/TiO2 oxides exhibit 15.1 times greater specific mass activity toward CO oxidation at 140 °C compared with a bare Pt/TiO2 catalyst. We elaborate how the CeOx–TiO2 interfaces activate the interface-mediated Mars–van Krevelen mechanism of CO oxidation and protect Pt single-atoms from CO-poisoning. Through a comprehensive interpretation of the formation and activation of dense Pt single-atoms using operando X-ray absorption spectroscopy, density functional theory calculations, and experimental catalyst performance tests, we provide a key that enables the catalytic performance of noble metal single-atom catalysts to be optimized by atomic-scale tuning of the metal–support interface.

The purpose of this study is to achieve enhanced solubility of cilostazol (CLT) by nanocrystal (NC) formation. CLT-NC was prepared by nanoprecipitation without the use of surfactant. To optimize particle size, we controlled four parameters, including the speed or power in the homogenizer or probe-sonicator, respectively, the processing temperature, drug concentration, and collection method. CLT-NC with a mean size of 500–600 nm was successfully prepared by a simple method. The small particle size was optimized by probe-sonication (200 W) at a low temperature (4 °C), drug concentration (4 mg/mL), and filtration (collecting method). The DSC thermograms and crystallinity of CLT exhibited a slight shift of on CLT-NC. The solubility of CLT-NC significantly increased 10.7-/7.6-/10.0-fold compared with that of CLT in different media (distilled water (DW), pH 1.2 and pH 6.8 buffers, respectively) for 24 h. Moreover, CLT-NC did not show the toxicity characteristic of CLT in the Caco-2 cells, and the nanocrystals were well maintained in 25 °C and 4 °C for 3 months. We developed CLT-NC with high solubility and non-toxic characteristics, which is expected to have high bioavailability in animals.