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The energy storage performance of lithium-ion batteries (LIBs) depends on the electrode capacity and electrode/cell design parameters, which have previously been addressed separately, leading to a failure in practical implementation. Here, we show how conformal graphene (Gr) coating on Ni-rich oxides enables the fabrication of highly packed cathodes containing a high content of active material (~99 wt%) without conventional conducting agents. With 99 wt% LiNi0.8Co0.15Al0.05O2 (NCA) and electrode density of ~4.3 g cm-3, the Gr-coated NCA cathode delivers a high areal capacity, ~5.4 mAh cm−2 (~38% increase) and high volumetric capacity, ~863 mAh cm-3 (~34% increase) at a current rate of 0.2 C (~1.1 mA cm-2); this surpasses the bare electrode approaching a commercial level of electrode setting (96 wt% NCA; ~3.3 g cm-3). Our findings offer a combinatorial avenue for materials engineering and electrode design toward advanced LIB cathodes., Li-ion battery electrodes contain inactive materials, such as conducting agents and polymeric binders, which limit the energy density. Here, the authors demonstrate highly dense Ni-rich cathodes with improved volumetric capacities by coating graphene and minimizing the inactive components.

This study proposed a structural model capturing the exhibitor’s internal resources, a trade show (TS) outputs and domestic market and international export performance derived from the conceptual f...

Purpose : This case report describes the successful results of vision therapy (VT) in divergence insufficiency esotropia (DI). Methods : A 19-year-old woman had diplopia with visual discomfort in daily life. At the first visit, she was judged intermittent DI with distance diplopia from binocular visual function tests. The VT program was designed to improve the patient’s negative fusional vergence including focus control, coordination training, ocular movement training, and visual function tests such as refraction, eye deviation, fusional ability, vergence facility, convergence near point, Bagolini lens test, Worth 4 dot test, and stereoacuity. Results : The deviation of eyes changed from 16 prism diopter(△) esotropia to 3 △ esophoria at distance after 9 months. At near, the deviation also changed from 7△ esotropia to 1 △ esophoria after VT. Fusional ability improved from X/4/1 to X/4/3 at distance and from BI X/8/2 to BI X/16/14 at near after VT of 9 months. Homonymous diplopia improved to single binocular vision by Bagolini striated glasses test. In the Bagolini striated glasses test, diplopia that appeared before VT was improved to single vision at all distances after training. The diplopia at distance, which complained severely at the first visit, gradually improved over the 9 months of VT, resulting in a stable single binocular vision. Conclusion : The binocular functions of the DI were successfully improved after VT of 9 months.

Background: In recent years, the use of the anterior half of the peroneus longus tendon (AHPLT) as an autograft source for ligament reconstruction has gained popularity. However, no reports are available regarding tendon regeneration after harvesting of the AHPLT. Hypothesis: When half of the tendon is preserved during tendon harvesting, the quality of the regenerated tendon is better than that of the regenerated tendon after full-thickness harvesting. Study Design: Case series; Level of evidence, 4; controlled laboratory study. Methods: A total of 21 patients who underwent AHPLT harvesting for lower extremity ligament reconstruction participated in the magnetic resonance imaging (MRI) study to evaluate tendon regeneration 1 year after the harvesting. An in vivo animal study was performed to compare the quality of the regenerated tendon after partial-thickness and full-thickness tendon harvesting. A total of 30 adult female Sprague-Dawley rats were allocated to 2 groups—15 rats underwent partial-thickness Achilles tendon harvesting (partial-thickness harvesting [PTH] group), and 15 rats underwent full-thickness Achilles tendon harvesting (full-thickness harvesting [FTH] group). The quality of the regenerated tendons was compared 180 days after tendon harvesting. Results: All 21 patients showed regeneration of the peroneus longus tendon (PLT) (homogeneously dark on both T1- and T2-weighted sequences). The cross-sectional area of the regenerated tendon divided by that of the preoperative tendon was 92.6% and 84.5% at 4 cm and 9 cm proximal to the tip of the distal fibula, respectively. In the animal study, the mean histologic score was better for the PTH group compared with the FTH group (9.17 ± 1.35 vs 14.72 ± 0.74; P < .001). The ultimate strength and the stiffness of the regenerated Achilles tendon were significantly higher for the PTH group compared with the FTH group (35.5 ± 8.3 vs 22.4 ± 8.3 N, P = .004; and 31.6 ± 7.7 vs 23.5 ± 4.8 N/mm, P = .016). Conclusion: The PLT was found to regenerate after partial-thickness harvesting on MRI. In the animal study, the quality of the regenerated tendon when half of the tendon was preserved during tendon harvesting was better than that after full-thickness tendon harvesting.

Purpose : To evaluate the anterior segment parameters (anterior chamber depth: ACD and anterior chamber angle: ACA) according to sex and age in Korean adults. Methods : The average age of the 92 subjects(160 eyes) was 35.38±15.75(20∼68) years old. The anterior segment parameters was measured by a rotating Scheimpflug camera(Pentacam, Oculus, Wetzlar, German). The ACD and ACA at 4 quadrants(superior, inferior, nasal and temporal) were measured and their averages were evaluated. Results : The total ACD was 2.97±0.39 mm in average. As the age increased, the ACD became shallower. The ACD for the nasal(1.87±0.39 mm) and the superior(1.85±0.39 mm) showed the significantly shallow depth than the ones for temporal(2.29±0.40 mm) and inferior (2.20±0.41 mm). In all 4 quadrants, the ACD gradually became shallower as the age increased 20s to 60s. The total ACA was 36.44±6.76°in average. As the age increased, the ACA became narrower. The ACA for superior(34.23±7.52°) and inferior(33.27±6.76°) showed the significantly narrow angle than the ones for the nasal(38.28±7.28°) and temporal (39.98±7.13°). In all 4 quadrants, the ACA gradually became narrower as the age increased 20s to 60s. Conclusion : As the age increases, the ACD and ACA become shallow and narrow but the decreases for 4 quadrants appeared different in tendency.

Purpose : The purpose of this study was to evaluate the intraocular pressure (IOP) that would be underestimated after corneal refractive surgery according to corneal ablation amounts, and was to suggest the most appropriate corrected IOP method for each group. Methods : The subjects were 1,002 eyes of 501 people (237 men, 264 women) who underwent corneal refractive surgery. The mean age was 26.89±5.18 years. IOP was measured with a non-contact tonometer and 4 correction methods, and was used to correct the underestimated IOP. IOP in three groups with low, moderate and high myopia according to ablation amounts was analyzed postoperative corrected IOP to compare correction methods. Results : The preoperative IOP was 15.67±2.39 mmHg and postoperative IOP was 10.12±2.11 mmHg, which was significantly lower than the mean 5.55±2.09 mmHg. The postoperative IOP calculated by Ehlers' correction method was 14.53±2.47 mmHg, which was 1.14±2.83 mmHg different from the preoperative IOP, showing the most similar to preoperative IOP. In addition, the IOP corrected by the Ehlers equation showed the smallest difference from preoperative IOP in all groups. Conclusion : The Ehlers correction method is shown the most accurate among the four correction methods in low, moderate, and high myopia groups after corneal refractive surgery. It would be a useful method for preventing the late diagnosis and treatment of glaucoma.

Li-ion batteries (LIBs) employ porous, composite-type electrodes, where few weight percentages of carbonaceous conducting agents and polymeric binders are required to bestow electrodes with electrical conductivity and mechanical robustness. However, the use of such inactive materials has limited enhancements of battery performance in terms of energy density and safety. In this study, we introduced graphene/polyvinylidene fluoride (Gr/PVdF) composites in Ni-rich oxide cathodes for LIBs, replacing conventional conducting agents, carbon black (CB) nanoparticles. By using Gr/PVdF suspensions, we fabricated highly dense LiNi0.85Co0.15Al0.05O2 (NCA) cathodes having a uniform distribution of conductive Gr sheets without CB nanoparticles, which was confirmed by scanning spreading resistance microscopy mode using atomic force microscopy. At a high content of 99 wt.% NCA, good cycling stability was shown with significantly improved areal capacity (Qareal) and volumetric capacity (Qvol), relative to the CB/PVdF-containing NCA electrode with a commercial-level of electrode parameters. The NCA electrodes using 1 wt.% Gr/PVdF (0.9:0.1) delivered a high Qareal of ~3.7 mAh cm−2 (~19% increment) and a high Qvol of ~774 mAh cm−3 (~18% increment) at a current rate of 0.2 C, as compared to the conventional NCA electrode. Our results suggest a viable strategy for superseding conventional conducting agents (CB) and improving the electrochemical performance of Ni-rich cathodes for advanced LIBs.

Purpose: This study examined the MICE Industry as an exchange and cooperation object to break through the inter-Korean relations in the crisis phase. Design/methodology/approach: This study conducted exploratory research applying grounded theory, a qualitative research method that builds a theoretical model through interviews with experts. Findings: The MICE industry is a viable alternative to inter-Korean exchange and cooperation and would play an essential role in improving inter-Korean relations. Paradoxically, the sanctions against North Korea reveal the MICE industry's discriminatory characteristics as a new paradigm for exchange and cooperation. Research limitations/implications: This study tried to build a theoretical exchange and cooperation model. Therefore, it is necessary to present specific strategies based on empirical and policy research in the future. Originality and Value: This study sought to approach inter-Korean exchange and cooperation, which had not been attempted before, from the perspective of the MICE industry.

Purpose: This study aims to analyze the efficiency of performance of exhibitors in overseas trade shows and identify the causes of inefficiency and differences according to their characteristics. Design/methodology/approach: This study employed a theoretical approach based on a literature research and an empirical analysis of companies that benefited from overseas exhibition support policies. Data envelopment analysis was used as a research method for analyzing the efficiency of 221 participating companies in overseas trade shows. Findings: The result exhibited little difference in the overall efficiency of exhibition performance according to the characteristics of exhibitors. However, performance in terms of the development of overseas markets differed dependent on the sales and export volume of exhibitors and the region of the trade shows. Furthermore, the finding demonstrated that net sales, exports, items, frequency of exhibiting in a trade show, and the rate of self-expenditure of the total costs of trade shows influence export promotion performance. Research limitations/implications: This study is significant in that it measured the efficiency of exhibition performance compared with the input of exhibitors in trade shows. However, the input variable was fixed and efficiency was analyzed using only a combination of three output variables. Thus, employing various input and output variables determine the causes of efficiency and inefficiency will lead to meaningful studies. Originality/value: This study measured the effectiveness of the overseas exhibition support policies of the government and the differences in the efficiency of exhibition performance according to the characteristics of beneficiary companies. This study differed from previous studies that simply analyzed the exhibition performance of companies. The results can be used as basic data necessary for establishing support policies for decision makers through measures for improvement, such as standards, contents, methods, and methods, as well as measures for the maximization of the efficiency of exhibition performance according to the characteristics of exhibitors