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In this paper, a switching method is proposed for power device temperature-balancing in a phase-shift full-bridge (PSFB) converter. PSFB is commonly used for applications that require high efficiency, because a zero-voltage switching (ZVS) operation is possible on the primary-side. In PSFB, the circulation current complicates ZVS under a light-load condition, which generates heat. Meanwhile, the heat generated in PSFB creates a temperature deviation between the lagging leg and the leading leg, which shortens the lifetime of the power device, thereby reducing system reliability and efficiency. To solve this problem, previous studies applied a pulse-width modulation (PWM) switching method for light and medium loads, and a phase-shift switching method for the region where ZVS is possible. Although this method has the advantage of easy control, the maximum temperature of the legs of the PSFB increases with medium loads. In this paper, a temperature-balancing algorithm—a temperature-balance control—is proposed to decrease the leg temperature using switching based on position exchanges of the leading leg and lagging leg along with PWM switching. Temperature-balance control minimizes leg temperature deviation under light load conditions. The proposed control method provides a minimum temperature difference between the two legs and high efficiency.

Structural maintenance of chromosome (SMC) proteins play a key roles in the chromosome organization by condensing two meters of DNA into cell-sized structures considered as the SMC protein extrudes DNA loop. Recent sequencing-based high-throughput chromosome conformation capture technique (Hi-C) and single-molecule experiments have provided direct evidence of DNA-loop extrusion. However, the molecular mechanism by which SMCs extrude a DNA loop is still under debate. Here, we review DNA-loop extrusion studies with single-molecule assays and introduce recent structural studies of how the ATP-hydrolysis cycle is coupled to the conformational changes of SMCs for DNA-loop extrusion. In addition, we explain the conservation of the DNA-binding sites that are vital for dynamic DNA-loop extrusion by comparing Cryo-EM structures of SMC complexes. Based on this information, we compare and discuss four compelling working models that explain how the SMC complex extrudes a DNA loop. [ABSTRACT FROM AUTHOR]

Abstract Various scoring systems have been developed to predict outcomes in patients with non-variceal upper gastrointestinal bleeding (NVUGIB). However, their accuracy remains unclear. This study aimed to compare and validate the predictive performance of several established scoring systems in patients with NVUGIB: Glasgow–Blatchford score (GBS) and the age, blood tests, and comorbidities (ABC), mental status–anesthesiologist score–pulse–albumin–systolic blood pressure–hemoglobin (MAP(ASH)), Japanese, and Charlson comorbidity index-in-hospital onset–albumin-mental status–Eastern Cooperative Oncology Group performance status–steroids (CHAMPS) scores. We retrospectively reviewed the records of 1,241 patients who presented to the emergency department with NVUGIB and subsequently required hospitalization. Each scoring system was evaluated for its ability to predict in-hospital mortality, rebleeding, and the need for radiological or surgical intervention. The ABC score showed the highest accuracy in predicting in-hospital mortality. The MAP(ASH) score was the most effective predictor of rebleeding and the need for interventions. Different scoring systems have been optimized for various clinical outcomes. The ABC score was the best for predicting mortality, whereas the MAP(ASH) score excelled in identifying rebleeding risks and intervention needs. The selection of an appropriate scoring tool based on specific clinical scenarios can improve patient management and resource allocation in NVUGIB.

Background/Objectives: The purpose of this study was to investigate the moderated mediation effect of teacher relations on the mediating effect of stress on the relationship between domestic abuse experience and depression in adolescents. Method/Statistical Analysis: To this end, approximately 860 middle and high school students from D city in Korea participated in the study survey. Collected data were analyzed using mean comparison analysis, reliability analysis, correlation analysis, and moderated mediation effect analysis. Findings: First, as a result of the difference test of depression according to general characteristics, there were significant differences according to gender, school grade, income level, and parent-teacher relationship. Second, as a result of the correlation analysis, there was a positive correlation between domestic abuse experience, stress, and depression, However, the teacher relationship negatively correlated with other variables. Third, stress was found to mediate between domestic abuse experience and depression. Fourth, teacher relationship was found to control between stress and depression. Fifth, teacher relations showed moderated mediation effects, on mediating effects of stress in the relationship between domestic abuse experience and depression. Improvements/Applications: Based on these findings, we discuss approaches to alleviating stress and reducing depression caused by domestic abuse experience. [ABSTRACT FROM AUTHOR]

Background/Objectives: The purpose of this study was to investigate the moderating effect of growth mindset on the mediating effect of stress on relationship between school violence victimization and school adaptation. Method/Statistical Analysis: The subjects of this study were 1,250 students living in H and S city of Chungnam-do, Korea. The collected data are analyzed using correlation analysis, frequency analysis, and moderating mediation effect. Findings: First, the correlation analysis showed a positive correlation between school violence victimization and stress, growth mindset and school adaptation. And, the school violence victimization was negatively correlated with a growth mindset and school adaptation, and stress was negatively correlated with a growth mindset and school adaptation. Second, the stress mediated the relationship between school violence victimization experiences and school adaptation. Third, growth mindset moderated the relationship between stress and school adaptation. Fourth, growth mindset moderated the mediating relationship of stress between school violence victimization and school adaptation. Improvements/Applications: Finally, based on the results of this study, it was suggested that the program to improve their growth mindset should be developed to increase school adaptation. In addition, we discussed regional comparisons through nationwide sampling, research on various age groups, and directions for research targeting only vulnerable groups. [ABSTRACT FROM AUTHOR]

Background/Objectives: The purpose of this study was to investigate the moderating mediation effect of lifelong education on the mediation effect of hope on suicide ideation in the elderly. The subjects of this study were 280 elderly people living in S city of Chungnam-do, Korea. Method/Statistical analysis: The collected data are analyzed using correlation analysis, frequency analysis, and moderating mediation effect. Findings: First, the correlation analysis showed a positive correlation between quality of life and hope, but there was a positive correlation between quality of life and suicide ideation, hope and suicide ideation. Second, the hope of the elderly mediated the relationship between the quality of life and suicide ideation. Third, participation in lifelong education of the elderly moderated the relationship between quality of life and hope. Fourth, participation in lifelong education of elderly people moderated the mediating relationship of hope between quality of life and suicide ideation. Improvements/Applications: Finally, based on the results of this study, it was suggested that a lifelong education program should be developed to lower the suicide intention of the elderly. In addition, we discussed regional comparisons through nationwide sampling, research on various age groups, and directions for research targeting only vulnerable groups. [ABSTRACT FROM AUTHOR]

The increasing frequency and severity of water-related disasters such as floods, tornadoes, hurricanes, and tsunamis in low- and middle-income countries exemplify the uneven effects of global climate change. The vulnerability of high-risk societies to natural disasters has continued to increase. To develop an effective and efficient adaptation strategy, local damage assessments must be timely, exhaustive, and accurate. We propose a novel deep-learning-based solution that uses pairs of pre- and post-disaster satellite images to identify water-related disaster-affected regions. The model extracts features of pre- and post-disaster images and uses the feature difference with them to predict damage in the pair. We demonstrate that the model can successfully identify local destruction using less granular and less complex ground-truth data than those used by previous segmentation models. When tested with various water-related disasters, our detection model reported an accuracy of 85.9% in spotting areas with damaged buildings. It also achieved a reliable performance of 80.3% in out-of-domain settings. Our deep learning-based damage assessment model can help direct resources to areas most vulnerable to climate disasters, reducing their impacts while promoting adaptive capacities for climate-resilient development in the most vulnerable regions.

Purpose: Obesity has been associated with higher total blood mercury levels, based on animal studies; however, studies that focus on children and adolescents are lacking. We aimed to assess the association between total blood mercury levels and the incidence of overweight and abdominal obesity in Korean adolescents. Methods: The study population comprised 1,567 adolescents (793 boys and 774 girls; aged 10-19 years), who participated in the Korea National Health and Nutrition Examination Survey 2010-2013. We analyzed total blood mercury levels according to obesity status in all participants. Results: The geometric mean of total blood mercury levels was 1.93 µg/L. Participants with overweight (2.20 µg/L) and obesity (2.17 µg/L) had higher levels than those with normal weight (1.86 µg/L, P<0.0001). The prevalence of overweight significantly increased with elevation of the total blood mercury quartile in both sexes. Increased incidence of abdominal obesity corresponding to increased total blood mercury level was observed in boys. After adjusting for covariates, those in the highest total blood mercury quartile were found to be at higher risk of overweight/obesity than those in the lowest quartile in both sexes (odds ratio [95% confidence interval]: boys, 3.27 [1.66-6.41]; girls, 1.90 [1.03-3.49]). The association between total blood mercury quartile and abdominal obesity was significant after controlling for covariates in boys (2.35 [1.05-5.24]). Conclusion: Our results suggest an association between total blood mercury levels and overweight in Korean adolescents. [ABSTRACT FROM AUTHOR]

This study retrospectively assessed whether time-lapse data relating to developmental timing and morphology were associated with clinical outcomes, with the eventual goal of using morphokinetic variables to select embryos prospectively for cryopreservation. In this study, we examined the clinical outcomes of single vitrified-warmed blastocyst transfer cycles that were cultured in a time-lapse incubation system. The morphokinetic variables included uneven pronuclei, an uneven blastomere, multinucleation, and direct, rapid, and irregular division. A total of 164 single vitrified-warmed blastocyst transfer cycles were analyzed (102 cycles of regularly developed blastocysts and 62 cycles of blastocysts with morphokinetic variables). No significant differences in the age of females or the standard blastocyst morphology were found between these two groups. The regularly developed blastocysts showed significantly higher implantation and clinical pregnancy rates than the blastocysts exhibiting morphokinetic variables (30.4% vs. 9.7% and 37.3% vs. 14.5%, respectively; p<0.01). The blastocysts that exhibited morphokinetic variables showed different mean development times compared with the regularly developed blastocysts. Although morphokinetic variables are known to have fatal impacts on embryonic development, a considerable number of embryos developed to the blastocyst stage. Morphokinetic variables had negative effects on the implantation and clinical pregnancy rates in vitrified-warmed blastocyst transfer cycles. These findings suggest that blastocysts cultured in a time-lapse incubation system should be considered for selective cryopreservation according to morphokinetic variables. [ABSTRACT FROM AUTHOR]

To address the ever increasing demand for wireless bandwidth, cognitive radio networks (CRNs) have been proposed to improve the efficiency of channel utilization. CRN permits unlicensed users to utilize the idle spectrum as long as it does not introduce interference to the primary users due to the Federal Communications Commission's recent regulatory policies. In this paper, we first identify some required distinctive security and privacy features for CRNs focused on ECMA-392, which is the first industrial standard for personal or portable devices in the television white spaces. After that, we propose a delegation based user authentication framework as a basic security and privacy module with full consideration of the required features over CRNs. The proposed framework provides privacy preserving yet accountable security within the CRN entities. Security and privacy analyses show that the proposed framework supports unlinkability, context privacy, anonymity, no registration and conditional traceability, which are the required security and privacy aspects in CRNs. [ABSTRACT FROM AUTHOR]

Purpose: We aimed to compare the clinical characteristics between neonates with persistent pulmonary hypertension of neonates (PPHN) with parenchymal lung disease (PLD) and those with idiopathic PPHN. Methods: We reviewed the medical records of 67 neonates with gestational ages not lesser than 34+0 weeks who were born at Inje University Sanggye Paik Hospital between June 1, 2005 and December 31, 2016. We excluded 10 neonates who presented with congenital anomalies (n=3), dextrocardia (n=1), triple X syndrome (n=1), death before treatment (n=1), neonatal asphyxia (n=2), and congenital diaphragmatic hernia (n=2). Neonates were categorized into 2 groups--PPHN with PLD (PLD group, those diagnosed with PLD such as respiratory distress syndrome or meconium aspiration syndrome, n=36) and idiopathic PPHN (idiopathic group, n=21). We compared the clinical characteristics, treatment, and laboratory findings between the groups. Results: The PLD group neonates showed a greater requirement for positive pressure ventilation in the delivery room, higher frequency of meconium staining of amniotic fluid, and greater need for surfactant application than those belonging to the idiopathic group. In contrast, epinephrine use was more common in the idiopathic PPHN group than in the PLD group. The 1-minute Apgar score and pH observed on initial capillary blood gas analysis were lower in the PLD than in the idiopathic group. Severity scores were higher in the idiopathic than in the PLD group 4-7 days after birth. Conclusion: In our study, an overall simplified severity score in the first week after birth was higher in the idiopathic than in the PLD group. These results were particularly statistically significant over postnatal days 4-7. [ABSTRACT FROM AUTHOR]

In this paper, we propose a parallelization method for a High Efficiency Video Coding (HEVC) deblocking filter with transform unit (TU) split information. HEVC employs a deblocking filter to boost perceptual quality and coding efficiency. The deblocking filter was designed for data-level parallelism. In this paper, we demonstrate a method of distributing equal workloads to all cores or threads by anticipating the deblocking filter complexity based on the coding unit depth and TU split information. We determined that the average time saving of our proposed deblocking filter parallelization method has a speed-up factor that is 2% better than that of the uniformly distributed parallel deblocking filter, and 6% better than that of coding tree unit row distribution parallelism. In addition, we determined that the speed-up factor of our proposed deblocking filter parallelization method, in terms of percentage run-time, is up to 3.1 compared to the run-time of the HEVC test model 12.0 deblocking filter with a sequential implementation. [ABSTRACT FROM AUTHOR]

Background: Antimicrobial resistance (AMR) is an issue not only with regard to public health, but also in terms of economic impact. AMR surveillance has mainly been carried out in general hospitals, and not in nursing hospitals. This study was conducted to investigate the AMR rate for bacterial strains isolated from nursing hospital samples.Methods: Antimicrobial susceptibility testing (AST) results from a total of 23,518 bacterial isolates recovered from clinical specimens taken in 61 nursing hosals were analyzed. AST was conducted using Vitek 2 with AST cards specific for the bacterial strains.Results: A total of 19,357 Gram-negative and 4,161 Gram-positive bacterial strains were isolated. Pseudomonas aeruginosa (n=6,384) and Escherichia coli (n=5,468) were the most prevalent bacterial species and, among Gram-positive bacteria, Staphylococcus aureus (n=1,565) was common. The AMR rate was high for the following strains: cefotaxime-resistant Klebsiella pneumoniae, 77.4%; cefotaxime-resistant E. coli, 70.6%; imipenem-resistant Acinetobacter baumannii, 90.3%; imipenem-resistant P. aeruginosa, 49.3%; oxacillin- resistant S. aureus, 81.1%, penicillin-resistant Enterococcus faecalis, 44.8%, and vancomycin-resistant Enterococcus faecium, 53.5%. AMR rate change varied by bacterial species and antimicrobial drug.Conclusion: AMR rates of major pathogens from nursing hospitals were higher than those from general hospitals with the exception of imipenem-resistant A. baumannii. Continuous monitoring and infection control strategies are needed. (Ann Clin Microbiol 2019;22:96-104)

Objective: This study was conducted to compare the effects of static culture, dynamic culture, and the combination of dynamic culture with specialized surfaces involving co-culture on human embryonic development. Embryos cultured using conventional static culture (SC) techniques served as a control group. We compared dynamic culture using micro-vibration culture (MVC) and micro-vibration with co-culture (MCoC), in which autologous cumulus cells were used as a specialized surface. Methods: We conducted a chart review of patients who were treated between January 2011 and November 2014 in order to compare embryonic development rates and pregnancy rates among the groups. Zygotes were cultured in micro-droplets, and embryos were subsequently selected for transfer. Some surplus embryos were cryopreserved, and the others were cultured for blastocyst development. A micro-vibrator was set at the frequency of 42 Hz for duration of 5 seconds per 60 minutes to facilitate embryo development. Results: No significant differences among the groups were present in patient's characteristics. However, the clinical pregnancy rates were significantly higher in the MVC group and the MCoC group than in the SC group. No significant differences were found in the blastocyst development rate between the SC group and the MVC group, but the blastocyst development rate in the MCoC group was significantly higher than in the SC and MVC groups. Conclusion: The clinical pregnancy rate was significantly increased by the application of micro-vibration to the embryonic cultures of poor responders. The blastocyst development rate was significantly increased by the application of MCoC to surplus embryos. [ABSTRACT FROM AUTHOR]

Alendronate (Alen)-modified hydroxyapatite (HAp) nanoparticles with multilayers of poly(allylamine) (PAA) and alginate (ALG) were fabricated for bone-specific dual delivery of drug and mineral. Negatively charged HAp nanoparticles were coated with three layers of PAA and ALG using a layer-by-layer (LbL) method and then conjugated with Alen at the outmost layer of the LbL-coated HAp nanoparticles via carbodiimide chemistry. Alenmodified HAp nanoparticles had a spherical morphology and an average size of 61.5 nm. The superior adsorption property of the Alen-modified HAp nanoparticles was quantitatively confirmed using tricalcium phosphate disks as a bone model, compared to HAp nanoparticles. Cell culture assays revealed a higher proliferation rate and alkaline phosphatase activity of osteoblasts treated with the Alen-modified HAp nanoparticles. [ABSTRACT FROM AUTHOR]

Objective: To study the clinical outcomes of single frozen-thawed blastocyst transfer cycles according to the hatching status of frozen-thawed blastocysts. Methods: Frozen-thawed blastocysts were divided into three groups according to their hatching status as follows: less-than-expanded blastocyst (≥EdB), hatching blastocyst (HgB), and hatched blastocyst (HdB). The female age and infertility factors of each group were evaluated. The quality of the single frozen-thawed blastocyst was also graded as grade A, tightly packed inner cell mass (ICM) and many cells organized in the trophectoderm epithelium (TE); grade B, several and loose ICM and TE; and grade C, very few ICM and a few cells in the TE. The clinical pregnancy and implantation rate were compared between each group. The data were analyzed by either t-test or chi-square analysis. Results: There were no statistically significant differences in average female ages, infertility factors, or the distribution of blastocyst grades A, B, and C in each group. There was no significant difference in the clinical pregnancy and implantation rate of each group according to their blastocyst grade. However, there was a significant difference in the clinical pregnancy and implantation rate between each group. In the HdB group, the clinical pregnancy and implantation rate were similar regardless of the blastocyst quality. Conclusion: There was an effect on the clinical outcomes depending on whether the blastocyst hatched during single frozen-thawed blastocyst transfer. When performing single frozen-thawed blastocyst transfer, the hatching status of the frozen-thawed blastocyst may be a more important parameter for clinical outcomes than the quality of the frozen-thawed blastocyst. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this retrospective study was to investigate shortterm and long-term skeletodental outcomes of Class 111 activator treatment. Methods: A Class 111 activator treatment group (AG) comprised of 22 patients (9 boys, 13 girls) was compared with a Class 111 control group (CG) comprised of 17 patients (6 boys, 11 girls). The total treatment period was divided into three stages; the initial stage (T1), the post-activator treatment or post-mandibular growth peak stage (T2), and the long-term follow-up stage (T3). Cephalometric changes were evaluated statistically via the Mann-Whitney L/-test and the Friedman test. Results: The AG exhibited significant increases in the SNA angle, ARB angle, Wits appraisal, A point-N perpendicular, Convexity of A point, and proclination of the maxillary incisors, from T1 to T2. In the long-term follow-up (T1-T3), the AG exhibited significantly greater increases in the ANB angle, Wits appraisal, and Convexity of A point than the CG. Conclusions: Favorable skeletal outcomes induced during the Class 111 activator treatment period were generally maintained until the long-term follow-up period of the post-mandibular growth peak stage. [ABSTRACT FROM AUTHOR]

Background: In phytotherapy, the therapeutic potential is based on the combined action of different herbal drugs. Our objective was to evaluate the antioxidant, anti-collagenase (in vitro), and anti-wrinkle (in vivo) effect of combined formulation containing Ginkgo biloba, Punica granatum, Ficus carica, and Morus alba fruits extract. Methods: Antioxidant evaluation was based on the scavenging activity of free radicals (1,1-diphenyl-2-picrylhydrazyl, H2O2, and O2- ) and the anti-collagenase activity was based on the reduction of collagenase enzyme in vitro. In an in vivo study, 21 female subjects were examined in a placebo-controlled trail. Facial wrinkle, especially the crow's feet region of eyes, was treated with topical formulated 2% cream for 56 days and compared with the placebo. Results: In the in vitro study, the combination of fruits extract showed a higher antioxidant activity which was comparable with the positive standard (ascorbic acid, butylated hydroxyanisole, and Trolox). The data also showed a dose-dependent inhibition of collagenase. In the in vivo study, treatment with 2% formulated cream for 56 days significantly reduced the percentage of wrinkle depth, length, and area with 11.5, 10.07, and 29.55, respectively. Conclusion: The combined formulation of fruit extracts showed excellent antioxidative and anti-collagenase activity as well as a significant effect on anti-wrinkle activity on human skin. [ABSTRACT FROM AUTHOR]

During intracellular membrane trafficking, N-ethylmaleimide-sensitive factor (NSF) and alpha-soluble NSF attachment protein (a-SNAP) disassemble the soluble NSF attachment protein receptor (SNARE) complex for recycling of the SNARE proteins. The molecular mechanism by which NSF disassembles the SNARE complex is largely unknown. Using single-molecule fluorescence spectroscopy and magnetic tweezers, we found that NSF disassembled a single SNARE complex in only one round of adenosine triphosphate (ATP) turnover. Upon ATP cleavage, the NSF hexamer developed internal tension with dissociation of phosphate ions. After latent time measuring tens of seconds, NSF released the built-up tension in a burst within 20 milliseconds, resulting in disassembly followed by immediate release of the SNARE proteins. Thus, NSF appears to use a "spring-loaded" mechanism to couple ATP hydrolysis and unfolding of substrate proteins. [ABSTRACT FROM AUTHOR]