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Purpose : This study aimed to identify the effects of a multifaceted pediatric delirium education program for pediatric intensive care unit (PICU) nurses on their delirium knowledge, confidence in delirium nursing, and delirium evaluation accuracy.Methods : This study used a one-group pretest-posttest design. The participants were 50 nurses in two units of the PICU at S General Hospital in Seoul. All participants took a 1-hour lecture with case-based practice for the first two weeks, and received feedback as they applied the program to clinical practice over the next two weeks. Test measures were completed before and after the four week intervention period for all participants. The delirium evaluation accuracy was measured using the Korean version of the Cornell Assessment of Pediatric Delirium. Data were analyzed using the chi-square and paired t-tests.Results : After the Pediatric Delirium Education Program, nurses’ delirium knowledge (x2 =11.65, p =.001), confidence in delirium nursing (t=9.71, p＜.001), and delirium evaluation accuracy (t=6.07, p＜.001) improved significantly.Conclusions : Pediatric delirium education programs for PICU nurses were effective. For active application of the program in clinical practice in the future, various cases of childhood delirium and specific strategies for each subject must be developed. To achieve this, long-term intervention and research for multiple organizations are required.

The skin structure of sensor pod mounted on the exterior of aircraft can be exposed to the acoustic dynamic load and static load such as aerodynamic pressure and inertial load during flight. Fatigue life prediction of structural model under acoustic load should be performed and also differential stiffness of model modified by static load should be considered. The acoustic noise test spectrum of MIL-STD-810G was applied to the structural model and the stress response power spectral density (PSD) was calculated. The frequency response analysis was performed with or without prestress induced by inplane static load, and the response spectrum was compared. Time series data was generated using the calculated PSD, and the time and frequency domain fatigue life were predicted and compared. The variation of stress response spectrum due to static load and predicted fatigue life according to the different structural model considering mean stress were examined and decreasing fatigue life was observed in the model with prestress of compressive static load.

In the treatment of diseases using medical bone scaffolds, it is necessary to design a customized bone scaffold according to the type of individual damage to restore normal bone function based on the damage information of each patient. In addition, the bone scaffold should serve to promote the regeneration of damaged bone in the patient. Compared to a rigid scaffold, a patterned scaffold inserted into a living body promotes bone formation more effectively. Therefore, using a metal 3D printer, it is important to incorporate artificial voids by controlling process variables so that the metal scaffold that replaces damaged bone can form a good bond with live tissue cells. In this study, Ti-6Al-4V ELI, which is actively used in the fields of medical implants and medical devices because of its excellent biocompatibility, was used to fabricate a metal hybrid scaffold that also provides external support. As for the process method, specimen production was conducted by controlling process parameters of the selective laser melting (SLM) method, which is one of the metal 3D printing techniques. Specimens fabricated for each scenario were analyzed by measuring flexural strength, and by imaging via optical microscopy (OM) and scanning electron microscopy (SEM). For OM analysis, the porosity was measured for each case and compared with the flexural strength. Thus, it was possible to adjust the strength by varying the internal pores via the process variables of the metal 3D printer. Accordingly, basic research was conducted to fabricate a metal osseous scaffold with strength similar to that of bone.

This study aims to provide a comprehensive review of key issues related to climate change to economists. For this purpose, we first discuss the established scientific facts of climate change and then discuss their implications to the economy and the field of economics. We start with explaining scientific consensus on climate change, types of climate risks and measures to mitigate them, need for international cooperation and the current state of South Korea. We then elaborate on economic perspectives of climate change and highlights the critical roles of economic research in this subject. In particular, we cover key discussions on economic modeling such as integrated assessment model (IAM), carbon pricing of carbon tax and cap & trade, climate finance, climate stress test, and green new deal. After reviewing key issues, we call for prompt attention from economists and policymakers to address since South Korea is facing relatively higher transition risks to low carbon economy.

In 2017 ‘Pink Shine’, a light pink spray rose cultivar,’ was bred by the National Institute of Horticulture & Herbal Science for the purposes of higher yield and longer vase l ife. This cultivar was developed by crossing ‘Fire Flash’, a reddish bicolor spray, with ‘Pink Charm’, a pink-colored spray cultivar resistant to powdery mildew. The crossing was performed in 2012 in anticipation of the pink colored spray and strong growth characteristics. Seeds were sown in January 2013, and planted in 9 cm pots. After the sensory evaluation, 39 seedlings were selected for the first selection group. Considering the flower shape, color, the number of petals, yield, and disease resistance, five lines were selected until 2015. Eventually, the ‘Wonkyo D1-325’ line was selected, and named ‘Pink Shine’ in 2017 through the first, second, and third characteristic tests for the 3 years from 2015 to 2017. An application for plant variety protection was registered on June 21, 2019 (No. 7786). The flower color of ‘Pink Shine’ is light pink (RHS, R36D), and the leaf color is green (RHS, G137A). The number of petals, the width of the flower, and the height of the flower were 67.8 cm, 5.4 cm, and 3.2 cm, respectively, which were all higher than ‘Missha’. The annual yield of the cut flower of ‘Pink Shine’ was 131 stems/m2 per year, and the vase life was superior to ‘Missha’.

Perilla, also termed as purple mint, Chinese basil, or Perilla mint, is a flavoring herb widely used in East Asia. Both crude oil and essential oil are employed for consumption as well as industrial purposes. Fatty acids (FAs) biosynthesis and oil body assemblies in Perilla have been extensively investigated over the last three decades. Recent advances have been made in order to reveal the enzymes involved in the fatty acid biosynthesis in Perilla. Among those fatty acids, alpha-linolenic acid retained the attention of scientists mainly due to its medicinal and nutraceutical properties. Lipids synthesis in Perilla exhibited similarities with Arabidopsis thaliana lipids’ pathway. The homologous coding genes for polyunsaturated fatty acid desaturases, transcription factors, and major acyl-related enzymes have been found in Perilla via de novo transcriptome profiling, genome-wide association study, and in silico whole-genome screening. The identified genes covered de novo fatty acid synthesis, acyl-CoA dependent Kennedy pathway, acyl-CoA independent pathway, Triacylglycerols (TAGs) assembly, and acyl editing of phosphatidylcholine. In addition to the enzymes, transcription factors including WRINKLED, FUSCA3, LEAFY COTYLEDON1, and ABSCISIC ACID INSENSITIVE3 have been suggested. Meanwhile, the epigenome aspect impacting the transcriptional regulation of FAs is still unclear and might require more attention from the scientific community. This review mainly outlines the identification of the key gene master players involved in Perilla FAs biosynthesis and TAGs assembly that have been identified in recent years. With the recent advances in genomics resources regarding this orphan crop, we provided an updated overview of the recent contributions into the comprehension of the genetic background of fatty acid biosynthesis. The provided resources can be useful for further usage in oil-bioengineering and the design of alpha-linolenic acid-boosted Perilla genotypes in the future.

This study presents hydrothermal carbonization (HTC) of leather waste (LW) to produce hydrochar and feasibility of using produced hydrochar as solid fuel. The results showed that a relatively low HTC treatment temperature (180–200 °C) improved both the hydrochar product yield (>82.9% by dry weight) and its potential use as a solid fuel with in terms of its physicochemical properties and heating value. Furthermore, the hydrochar showed a higher heating value (5807–6508 kcal kg −1 ) compared to that of low-ranked coals ( i.e., sub-bituminous and lignite), and stable combustion characteristics at a higher temperature. This allows the hydrochar to be considered as a suitable alternative to conventional fossil fuel. In addition, the decrease of nitrogen content in the hydrochar during the HTC treatment, and the inherent low sulfur content of LW could make hydrochar a more appealing clean energy source. The findings of this study suggest that the conversion of LW through HTC can be a useful method for waste management and energy recovery from abandoned biomass.

This paper revisits the question of whether investors can benefit from consensus recommendations of stock market analysts in US equity markets. To examine the profitability net of transactions cost, we calculate several measures of transactions costs based on effective tick spreads and others. We find that transactions cost becomes noticeably lower from 2001 and the strategy of purchasing ‘strong buy’ stocks and shorting ‘strong sell’ stocks yields the abnormal returns of 4.7–5.8% per year during the period of 2001–2016, even after accounting for transactions cost. We also find that ‘strong buy (sell)’ stocks are growth (value) firms and short-term winners (losers). We discuss our empirical results in the context of market efficiency.

Struvite precipitation is an effective method to remove and recover ammonia and phosphate from livestock wastewater. Struvite has properties similar to those of the traditional ammonium-phosphate fertilizer, which does not burn the roots owing to its slow-release characteristics. Struvite is an effective fertilizer as its nutrient-releasing rate is very slow. But the release rate of ammonia and phosphate in soil depends on the size of crystals. In this study, the nutrient-releasing pattern of three types of struvite crystals and liquid fertilizer was compared using soil column. X-Ray fluorescence spectrometry was conducted to investigate the potential use of struvite as a fertilizer. Various struvite crystalline fertilizers were evaluated for their fertilizer performance by cultivating potted vegetable crops. The nitrogen removal efficiency of zeolite-seeded struvite was higher than that of no seed struvite. The ammonia nitrogen removal efficiency was more than 99% irrespective of the kind of zeolite. The soil column test revealed that nutrient releasing from liquid fertilizer and zeolite-seeded struvite recovered from livestock wastewater was 11 and 63 days, respectively. Struvite recovered from livestock wastewater contained more than 20% (w/w) potassium oxide; however, the concentration of heavy metals, such as copper and zinc, was very low. Therefore, we considered that the synthesized struvite using livestock wastewater has high value as fertilizer. The recovered struvite was effective under appropriate concentrations to cultivate all the applied vegetable crops in this study.

Following an idea of Milton Friedman's “plucking model,” we propose to use a state-space model with Markov switching as an auxiliary tool for detecting currency manipulation. Without imposing any a priori restrictions, our model tests if fluctuations of a country's exchange rate are symmetric or if there exists a time-varying support level or resistance level of exchange rate. Using weekly and monthly data of countries on the “monitoring list” of the US Treasury as of April 2017, we find that exchange rates of China, South Korea, Switzerland, and Taiwan rarely fall below their time-varying trends, but are plucked upward from time to time by transitory shocks, suggesting that the FX (foreign exchange) authorities of these countries may have been intervening more actively against appreciation shocks. Our sub-sample analysis reveals that our model accurately captures the period of Switzerland's minimum exchange rate policy with probability of one and Japan's exchange rate rarely falls below its trend after implementing Abenomics. We discuss the difficulties of detecting FX intervention along with the relative advantage of our approach.

In this study, an open pond constructed in Myanmar, a region with tropical climate and favorable environmental conditions for algae growth, was considered to conduct field experiments on sewage inflow river water. The nutrient removal efficiency and productivity of Hydrodictyon reticulatum (H. reticulatum) were analyzed, and the maximum fermentation limit concentration for bioethanol production was determined. Three ponds were operated in batch mode to investigate the effect of light intensity. Photoinhibition was caused due to excessive light intensity in summer season in the region with tropical climate resulting in reduced facility efficiency in the absence of shade. For light blocking, a transparent film was found to be more effective than a translucent film. In the transparent film shading facility, the nitrogen and phosphorus removal efficiencies were maintained above 76% and 81%, respectively, and the productivity of H. reticulatum was 2.27 g m

Although microalgae are seen as a potential alternative source of energy and other materials currently sourced from petroleum, issues still remain with industrialization because of difficulties in developing commercially operational microalgal production systems. We set up a pilot-scale study that involved the simultaneous reuse of wastewater and production of algae under different light and harvesting conditions. We cultivated Hydrodictyon reticulatum (H. reticulatum), a type of water-net algae, using secondary effluent from a wastewater treatment plant in a raceway open pond combined with an underwater light device. Experimental results showed that the underwater light device maintained some level of underwater light throughout the year. Photoinhibition of algal growth only occurred when the sunlight exceeded 1270 μmol m−2 s−1. During the non-harvest process, the maximum algal concentration was 1700 mg L−1 at 20 days after the experiment began, the maximum specific growth rate was 0.18 d−1 and the maximum productivity was 21.3 g m−2 d−1. Conversely, periodic harvesting decreased the concentration of nutrients in the effluent more as the days of cultivation increased, but the productivity of algae also decreased to 11.7 g m−2 d−1. The maximum yield of bioethanol using three kinds of fermentation strains was 93.5% and, thus, the commercial value of H. reticulatum as a raw material for energy production was excellent.

In this study, heavy metal-containing sunflower residues obtained from a phytoremediation site were hydrothermally carbonized at 160–260 °C. The properties of hydrochar thus produced were evaluated with respect to its potential as solid fuel. The results confirmed that hydrothermal carbonization (HTC) reduced the concentration of heavy metals in hydrochars, with the concentration lower than the maximum permissible level of domestic standards for bio-solid refuse fuel. Higher HTC temperatures resulted in improved energy-related properties of the hydrochar (i.e., coalification degree, fuel ratio, and higher heating value); however, HTC temperatures between 200 and 220 °C were deemed suitable for energy retention efficiency. Furthermore, as hydrochar contains low nitrogen and ash content, it can be considered as a clean energy source. The results of this study suggest a sustainable approach to the disposal and effective utilization of contaminant-containing biowastes. Moreover, this study suggests linking biomass cultivation for phytoremediation and converting the phytoremediated biomass into value-added solid fuel.

In this study, the separation of metals from electroplating wastewater using an electrodialysis system was investigated. The separation efficiency of the metal ions increased as the applied...

Recent development in industry has led to increased water usage, while intensifying water shortage. Electrodialysis has been proposed as a technique for minimizing the generation of secondary environmental pollution problems and effectively treating harmful substances such as heavy metals in industrial wastewater. As electrodialysis is affected by several factors, it is crucial to provide necessary information about the operating elements. This study investigates the effect of linear flow velocity on the removal of heavy metals in an electrodialysis pilot plant. The results of the experiment showed that increasing the linear flow velocity from 0.6 to 5.1 cm/min increased the voltage from 17.3 to 40 V. In addition, the limiting current density (LCD) showed a linear relationship with the linear flow velocity, increasing from 1.4 to 5.9 A/m2 as the linear flow velocity increased proportionally in the same voltage range. The empirical correlation coefficients a and b for the mass transfer coefficient K, which can be expressed as a nonlinear function of the linear flow velocity, were estimated to be 1.8519 and 0.7016, respectively. In the batch operation, the ion-separation rate in the electrodialysis process was estimated with the shift order kinetics of the first-order and zero-order constants via regression analysis of experimental data. The ion separation rate in the diluate and the ion concentration rate in the concentrate decrease as the experiment number increase. This may be due to the reverse diffusion of ions transferring to the diluate owing to the high concentration of ions in the concentrate. Therefore, ion concentration in the concentrate has to be maintained at an appropriate level. Copper ions are deposited on the cathode electrode surface, although not uniformly.

Although the struvite crystallization process has proven to be an effective process for the recovery of nutrients from wastewater, this process has not been widely used due to the excessive use of chemicals. In this study, the optimal production conditions, yield, and economic feasibility of struvite using the anaerobic digestion of livestock wastewater were investigated. In addition, the economic feasibility of adding zeolite to improve the productivity of struvite and additionally remove nitrogen was evaluated. The result of the experiment on the struvite yield change according to the molar ratios at pH 9.0 showed that the struvite yield ratio was 99.0% of the stoichiometric yield at the Mg2+ :NH4+ :PO43− molar ratios of 1.2:1.0:1.1. As a magnesium source, MgCl2, concentrated seawater in the seawater desalination process, and MgO were compared, and when MgO was used, struvite productivity and economic efficiency were the best. Also, while the addition of zeolite greatly increased the struvite production and zeolite was also sold as a soil conditioner, the struvite sales benefit was estimated to be 103% of the operating cost.

Roses are one of the most highly produced and purchased ornamental plants worldwide. Procurement and preservation of pollen is essential for the production of diverse rose varieties. In this study, we analyzed pollen management conditions, such as the pollen collection stage, drying time, and storage temperature, to determine optimal conditions for rose pollen management. Pollens were stored under different conditions and the pollen vitality and germination rate were investigated through an optical microscope. The vitality of pollen was an essential factor for rose breeding and depended on the storage conditions. Collecting pollen in the seventh flowering stage resulted in a relatively higher pollen yield. Drying the flower for 5 h after the anther opened improved pollen germination. The germination rate of freshly collected pollen was similar to that of pollen stored at temperatures between −20 °C and −72 °C for up to 30 days, indicating the efficacy of pollen storage at sub-zero temperatures. Since the rate of fruiting increases when pollination is performed three times, considering the time and cost of breeding, it is appropriate to pollinate three times to increase the number of seeds. This study provides an efficient pollen management method to collect and store pollen for breeding.

While South Korea has achieved remarkable economic and democratic transformation during the past decades, it has suffered from two major economic crises, both of which are essentially liquidity crises. In this regard, the purpose of this study is twofold: one is to review the debates on capital market liberalisation and highlight the dark sides of South Korea’s experience. The other is to explain why South Korea has experienced another crisis in 2008 even though it already experienced the same liquidity crisis in 1997. We highlight the unintended consequences of policies with their own legitimate purposes and provide lessons on capital market liberalisation for emerging economies.

The current study evaluated nutrient removal efficiency, algae productivity, and economic feasibility related to cultivation of the filamentous algae, Hydrodictyon reticulatum, in a pilot plant-sca...

Using “2014 Time Usage and Quality of Life” of 17th KLIPS (Korean Labor and Income Panel Study), the first and most detailed time use survey of its kind in South Korea, we first document the patterns of time use in market work, nonmarket work (household work), child care, and a variety of definitions in leisure. We find that, while men work longer hours, men’s additional market work is well compensated by more leisure and less hours in nonmarket work and child care. We also find within-household unequal distribution of time use in nonmarket work, child care, and leisure in favour of men. Consistent with the cases of US and other advanced economies, high-income earners tend to enjoy less hours of leisure while they spend more money in leisure activities. Secondly, we calculate the household-level consumption equivalent measure that considers consumption, leisure, life expectancy, and uncertainty. We find that taking into account non-separable preference over leisure and consumption and quality of leisure is important and household-level welfare measures based solely on income or consumption are both incomplete and misleading.

The aim of this work was to study the characterized hydrochar of algal biomass to produce solid fuel though hydrothermal carbonization. Hydrothermal carbonization conducted at temperatures ranging from 180 to 270 °C with a 60 min reaction improved the upgrading of the fuel properties and the dewatering of wet-basis biomasses such as algae. The carbon content, carbon recovery, energy recovery, and atomic C/O and C/H ratios in all the hydrochars in this study were improved. These characteristic changes in hydrochar from algal biomass are similar to the coalification reactions due to dehydration and decarboxylation with an increase in the hydrothermal reaction temperature. The results of this study indicate that hydrothermal carbonization can be used as an effective means of generating highly energy-efficient renewable fuel resources using algal biomass.

In this study, hydrothermal carbonization was conducted to convert lipid extracted algae (Chlorella vulgaris) from the algal biodiesel process to produce hydrochar, while evaluating its feasibility for use as a solid fuel. Hydrothermal carbonization was conducted at a relatively low temperature range, owing to the energy consumption during the process. Based on the results, the properties of lipid extracted algae as a solid fuel improved during hydrothermal carbonization, being comparable to the low-ranked coals. The hydrochars thus produced showed stable combustion characteristics at high temperature. Moreover, the sulfur and ash content in the lipid extracted algae decreased through devolatilization during hydrothermal carbonization, allowing the hydrochar (low sulfur and ash content) to be considered as a clean energy source. Thus, a sustainable integration process, combining the hydrochar production from lipid extracted algae with the algal biodiesel process, seems to be feasible for solid fuel production and disposal of waste.

Although surgical techniques for treating acetabular fracture are evolving, the use of periacetabular screws is common, and their placement in acetabular surgery is still technically demanding. For instance, intraarticular screw perforation is a serious complication that may occur during surgical treatment of an acetabular fracture. Here, we describe the case of a 50-year-old female who experienced an intraarticular screw perforation after surgical treatment of a posterior acetabular wall fracture. Removal of the perforated screw was performed arthroscopically based on its ability to offer minimally invasive access to the hip joint. One year after removal of the screw, no radiological signs of osteoarthritic changes were observed. The patient regained normal ambulation without limitations to range of motion or hip pain. To our knowledge, this is the first report on the use of arthroscopy to treat intraarticular screw perforation after surgical treatment of an acetabular fracture.