Search

Background and Objectives The aim of this study was to compare adherence to positive airway pressure (PAP) therapy in patients with obstructive sleep apnea (OSA) of different severity.Subjects and Method We conducted a retrospective study including 270 adult OSA patients who used a PAP device for at least 3 months. We assessed the percentage of days on which the device was used, the percentage of days on which the device was used for ≥4 h, and the average duration of PAP device usage at 12 weeks of PAP therapy. We also evaluated adequate adherence to PAP therapy using a PAP device for ≥4 h/day and during ≥70% of nights.Results The percentage of days on which a PAP device used did not differ significantly according to OSA severity (median [Q1-Q3]; mild: 91.40% [81.25%-97.65%], moderate: 94.50% [86.90%-100%], severe: 95.90% [88.10%-100%], p=0.268). We also found that the percentage of days on which a PAP device was used during sleep for ≥4 h was not significantly different in patients with different OSA severity (median [Q1-Q3], mild: 76.20% [69.70%-89.90%], moderate: 89.30% [67.65%-95.70%], severe: 85.70% [75.85%-95.45%], p=0.097). The percentage of patients with adequate PAP adherence did not differ significantly according to OSA severity (mild: 74.2%, moderate: 72.1%, severe: 83.0%, p=0.084). Moreover, the mean duration (minutes) of PAP device usage during sleep did not differ significantly according to OSA severity in the mild, moderate, and severe OSA groups (mean±standard deviation, mild: 348.03± 47.78 min, moderate: 358.58±85.22 min, severe: 363.79±57.21 min, p=0.440).Conclusion Adherence to PAP therapy did not differ significantly according to OSA severity. Therefore, it is necessary to continuously expand and maintain the insurance for health promotion in OSA patient in South Korea.

Litter and compost were obtained at a cowshed of a livestock farm in Andong city in Korea. The morphological change of nitrogen and phosphorous from these samples were examined and suggested a more useful and realistic way for reducing them. Constituents and their content of sample were identified by XRF. The nitrite ion (NO2 −), nitrate ion (NO2 −) and phosphate ion (PO4 3−) and ammonium ion (NH4 +), total phosphorous (T-P) and total nitrogen (T-N) released from sample were analyzed using ion chromatograph and UV/Vis spectrometry. As the results of this study, the ammonia in the early stage of cow excretion is a need to make an ammonia gas state that can be immediately volatile by increasing the pH. Nitrogen and phosphorous, the main source of nutrition in green algal bloom can be reduced by transforming insoluble salts such as calcium phosphate (CaHPO4·3H2O) and struvite (NH4MgPO4·6H2O), respectively, with addition of Ca and Mg after stimulating fermentation of compost.

OBJECTIVES The aim of this study was to analyze the association between obstructive sleep apnea (OSA) severity and various cardiopulmonary coupling (CPC) parameters in children with OSA. STUDY DESIGN Retrospective cross-sectional study. METHODS A cross-sectional study was conducted among 117 children (aged 7.96 ± 3.54 years, 86 male) who underwent both full-night polysomnography (PSG) and CPC for suspicion of sleep-disordered breathing (SDB). We analyzed the association between various CPC and PSG findings. RESULTS The apnea-hypopnea index (AHI) was negatively correlated with high frequency coupling (HFC, r = -0.374, P

PurposeThe purpose of this paper is to explore and examine the different word-of-mouth (WOM) acceptance and diffusion in social brand communities according to the level of self-monitoring.Design/methodology/approachA web-based experimental design was used. The design consisted of three-mixed design of 2 (type of social networking sites) × 2 (type of online brand communities) × 2 (self-monitoring). ANOVA analysis was conducted.FindingsFindings indicate that the differences in acceptance and diffusion of WOM according to online brand community type, and there was a significant three-way interaction effect. Specifically, people who have high propensity to self-monitor showed greater WOM acceptance in a consumer-driven community in either type of social networking sites while people who have low propensity to self-monitor showed greater WOM diffusion in a consumer-driven community only in interest-based social networking sites.Practical implicationsAn important implication is that the social networking sites where brand communities can be placed should be chosen with the full consideration of different desires consumers have in terms of their level of self-monitoring to increase WOM effects.Originality/valueThis paper proposes the self-monitoring tendency as the key factor that predicts WOM effects with revealing the optimal combination of types of social networking sites and online brand communities that is most preferable for consumers with different self-monitoring level.

OBJECTIVES The aim of this study was to assess the sleep quality and sleep stability according to the severity of obstructive sleep apnea (OSA) by using questionnaires and cardiopulmonary coupling (CPC) analysis. METHODS Two hundred and twenty-one adults were evaluated using subjective sleep questionnaires, CPC parameters, and respiratory parameters measured during full-night polysomnography. We measured the differences in the CPC parameters of each OSA group and the correlation between the apnea-hypopnea index (AHI) and CPC parameters. RESULTS AHI and CPC parameters were not associated with sleep questionnaires. AHI is negatively correlated with high frequency coupling (HFC, r = -0.725, P

Positional change during sleep influences upper airway patency. However, few studies have used imaging techniques to demonstrate the change. This study aims to determine the effect of positional change on the upper airway space. A total of 118 subjects with sleep breathing disorders were analyzed. Participants underwent upper airway CT scans in the supine and lateral decubitus positions (right and left). They were divided into non-obstructive sleep apnea (n = 28) and obstructive sleep apnea (n = 90) groups. We measured the minimal cross-sectional area of the retropalatal/retroglossal spaces and compared the differences of those two spaces in the supine and lateral positions. CT was performed while patients were awake. The minimal cross-sectional area in the OSA group was significantly smaller than non-OSA group in both supine (median[interquartile range], 8.3[0.0–25.1] vs 22.2[1.0–39.6]; P = 0.018) and lateral decubitus positions (5.2[0.0–16.9] vs 21.3[6.1–38.4]; P = 0.002). As the body position of OSA patients shifted from supine to lateral, the retroglossal space increased significantly (67.3[25.1–116.3] vs 93.3[43.4–160.1]; P

Objectives Improvements in sleep-related quality of life (QOL) and behavioral problems have been observed in children with obstructive sleep apnea (OSA) during a short-term follow-up after adenotonsillectomy. Whether this trend continues beyond the short term remains unclear. Therefore, we aimed to evaluate the long-term effects of surgery in children with OSA. Methods The study participants comprised 20 children with OSA who underwent adenotonsillectomy. We used the scores from the Attention Deficit and Hyperactivity Disorder Rating Scale (ADHD-RS) and total scores from the Korean OSA-18 Survey (KOSA-18) before and after adenotonsillectomy to compare and analyze behavioral problems and OSA-specific health-related QOL, respectively, during a long-term follow-up. Respiratory disturbance parameters from standard polysomnography and subjective symptom scores for snoring and apnea were also investigated. Results The mean patient age was 6.6 ± 3.4 years (range, 3-13), and the male-to-female ratio was 15:5. The mean follow-up period was 54.5 months (range, 27-98). The total scores for both ADHD-RS (from 17.6 to 10.5; P = 0.006) and KOSA-18 (from 74.3 to 40.7; P = 0.001) decreased significantly from before to after surgery. Significant decreases were also observed in the subjective symptom scores for snoring (from 5.4 to 2.4; P = 0.000) and apnea (from 3.3 to 0.8; P = 0.002). Conclusion Significant improvement was observed in sleep-related QOL and behavioral problems in children with OSA during long-term follow-up after adenotonsillectomy. Level of evidence 4 Laryngoscope, 130:546-550, 2020.

The purpose of the research was to determine the effects of cultural self-construal of users in social networking sites (SNS) on the way they perceive self-disclosing activities, attach to brand community, and satisfy with brand relationship. With the growth of social media, it has brought diverse users from different countries in a single platform enabling people from divergent cultures to communicate and be influenced by each other shaping unique self-construal. Hence, we used newly developed cultural self-construal as an antecedent of self-disclosure. Data were collected from 460 female adults. The results showed that the perceptions of self-disclosure are the key antecedents of relationship advancement, which are differently influenced by cultural self-construal. The way users perceive self-disclosing activities positively influenced brand community attachment, and subsequently brand relationship satisfaction. The results provided valuable insights for practitioners by presenting the importance of using brand community in SNS as a long-term branding channel.

The contribution ratio of autotrophic and heterotrophic metabolism in the mixotrophic culture of Chlorella sorokiniana (C. sorokiniana) was investigated. At the early stage of mixotrophic growth (day 0–1), autotrophy contributed over 70% of the total metabolism, however, heterotrophy contributed more than autotrophy after day 1 due to the rapid increase in cell density, which had a shading effect in the photo-bioreactor. Heterotrophy continued to have a higher contribution until the available organic carbon was depleted at which point autotrophy became dominant again. Overall, the increase in algal biomass and light conditions in the photo-bioreactor are important factors in determining the contribution of autotrophy and heterotrophy during a mixotrophic culture.

To compare postoperative pain, nausea and vomiting, and bleeding between intravascular dexamethasone injection group and control group among children undergoing powered intracapsular tonsillectomy and adenoidectomy (PITA).Retrospective review of medical records was performed for pediatric patients who underwent PITA from March 1, 2017, to February 28, 2021, at a tertiary referral medical center in South Korea. Postoperative pain and nausea were measured using the visual analogue scale (VAS) from the postoperative day (POD) 0 to POD 6. The number of analgesics administered and the number of vomiting episodes were recorded in the same period. The repeatedly measured parameters were statistically analyzed between the dexamethasone group and control group.A total of 71 children with complete questionnaires including 44 boys and 27 girls were included, and the mean age was 7.49 ± 2.44 years. There were 33 patients in the dexamethasone group and 38 in the control group. Postoperative pain (p = 0.169) or nausea (p = 0.460) on the VAS showed no statistically significant difference between the two groups. Postoperative analgesics showed no difference between the groups (p = 0.398), and neither did postoperative vomiting (p = 0.270). In both groups, no child showed signs of postoperative bleeding.This study indicates that the beneficial effects of intravascular dexamethasone administration in PITA may not be evident. This might be due to the superior outcome of the PITA technique compared to total extracapsular tonsillectomy. Therefore, otolaryngologists performing PITA may not necessarily need to administer dexamethasone in children before surgery.

Background Olfactory and gustatory dysfunction has been reported as characteristic symptoms of coronavirus disease 2019 (COVID-19). This study evaluated olfactory and gustatory dysfunction in mild COVID-19 patients using validated assessment methods. Methods A prospective surveillance study was conducted for mild COVID-19 patients who were isolated at the Gyeonggi International Living and Treatment Support Center (LTSC), Korea. Olfactory function was assessed using the Korean version of the Questionnaire of Olfactory Disorders (QOD) and Cross-Cultural Smell Identification Test (CC-SIT). Gustatory function was assessed using an 11-point Likert scale and 6-n-propylthiouracil, phenylthiocarbamide, and control strips. All patients underwent nasal and oral cavity endoscopic examination. Results Of the 62 patients at the LTSC, 15 patients (24.2%) complained of olfactory or gustatory dysfunction on admission. Four of 10 patients who underwent functional evaluation did not have general symptoms and 2 were asymptomatic. The mean short version of QOD-negative statements and QOD-visual analogue scale scores were 13 ± 6 and 4.7 ± 3.6, respectively. The mean CC-SIT score was 8 ± 2. No patients showed anatomical abnormalities associated with olfactory dysfunction on endoscopic examination. The mean Likert scale score for function was 8 ± 2, and there were no abnormal lesions in the oral cavity of any patient. Conclusions The prevalence of olfactory and gustatory dysfunction was 24.2% in mild COVID-19 patients. All patients had hyposmia due to sensorineural olfactory dysfunction, which was confirmed using validated olfactory and gustatory evaluation methods and endoscopic examination. Olfactory and gustatory dysfunction may be characteristic indicators of mild COVID-19., Graphical Abstract

Supported with significant rejuvenating and regenerating actions of mesenchymal stem cells (MSCs) in various gastrointestinal diseases including Helicobacter pylori (H. pylori)-associated gastric diseases, we have compared these actions among placenta derived-MSCs (PD-MSCs), umbilical cord derived-MSCs (UC-MSCs), and adipose tissue derived-MSCs (AD-MSCs) and explored contributing genes implicated in rejuvenation of H. pylori-chronic atrophic gastritis (CAG) and tumorigenesis. In this study adopting H. pylori-initiated, high salt diet-promoted gastric carcinogenesis model, we have administered three kinds of MSCs around 15–18 weeks in H. pylori infected C57BL/6 mice and sacrificed at 24 and 48 weeks, respectively, in order to either assess the rejuvenating capability or anti-tumorigenesis. At 24 weeks, MSCs all led to significantly mitigated atrophic gastritis, for which significant inductions of autophagy, preservation of tumor suppressive 15-PGDH, attenuated apoptosis, and efficient efferocytosis was imposed with MSCs administration during atrophic gastritis. At 48 weeks, MSCs administered during H. pylori-associated atrophic gastritis afforded significant blocking the progression of CAG, as evidenced with statistically significant reduction in H. pylori-associated gastric tumor (p

Dietary intervention to prevent Helicobacter pylori (H. pylori)-associated gastric diseases seems to be ideal with no risk of bacterial resistance, safe long-term intervention, and correcting pathogenic mechanisms including rejuvenation of precancerous atrophic gastritis and anti-mutagenesis. A transcriptome as set of all RNAs transcribed by certain tissues or cells demonstrates gene functions and reveals the molecular mechanism of specific biological processes against diseases. Here, we have performed RNAseq and bioinformatic analysis to explain proof of concept that walnut intake can rescue from H. pylori infection and explore unidentified mode of actions of walnut polyphenol extract (WPE). As results, BIRC3, SLC25A4, f3 transcription, VEGFA, AZU1, HMOX1, RAB3A, RELBTNIP1, ETFB, INPP5J, PPME1, RHOB, TPI1, FOSL1, JUND.RELB, KLF2, MUC1, NDRG1, ALDOA, ENO1, PFKP, GPI, GDF15, and NRTN genes were newly discovered to be enriched with WPE, whereas CCR4, BLNK, CCR7, CXCR4, CDO1, KLSG1, SELE, RASGRP2, PIK3R3, TSPAN32, HOXC-AS3, HCG8, BTNL8, and CXCL3 genes as inhibitory targets by WPE in H. pylori infection. We identified additional genes what WPE afforded actions of avoiding H. pylori-driven onco-inflammation and rejuvenating precancerous atrophic gastritis. Conclusively, after applying RNAseq analysis in order to document walnut intake for precision medicine against H. pylori infection, significant transcriptomic profiling applicable for validation were drawn.

We designed an experiment to analyze the gut content of Rotifera based on DNA barcoding and tested it on Asplanchna sp. in order to ensure that the DNA extracted from the rotifer species is from the food sources within the gut. We selected ethanol fixation (60%) to minimize the inflow effects of treated chemicals, and commercial bleach (the final concentration of 2.5%, for 210 s) to eliminate the extracellular DNA without damage to the lorica. Rotifers have different lorica structures and thicknesses. Therefore, we chose a pretreatment method based on Asplanchna sp., which is known to have weak durability. When we used the determined method on a reservoir water sample, we confirmed that the DNA fragments of Chlorophyceae, Diatomea, Cyanobacteria, and Ciliophora were removed. Given this result, Diatomea and cyanobacteria, detected from Asplanchna, can be considered as gut contents. However, bacteria were not removed by bleach, thus there was still insufficient information. Since the results of applying commercial bleach to rotifer species confirmed that pretreatment worked effectively for some species of rotifers food sources, in further studies, it is believed to be applicable to the gut contents analysis of more diverse rotifers species and better DNA analysis techniques by supplementing more rigorous limitations.

Background: Olfactory and gustatory dysfunction have been reported as characteristic symptoms of coronavirus disease 2019 (COVID-19). This study evaluated olfactory and gustatory dysfunction in mild COVID-19 patients using validated assessment methods. Methods: A prospective surveillance study was conducted for mild COVID-19 patients who were isolated at the Gyeonggi International Living and Treatment Support Center (LTSC), Korea. Olfactory function was assessed using the Korean version of the Questionnaire of Olfactory Disorders (QOD) and Cross-Cultural Smell Identification Test (CC-SIT). Gustatory function was assessed using an 11-point Likert scale and 6-n-propylthiouracil, phenylthiocarbamide, and control strips. All patients underwent nasal and oral cavity endoscopic examination. Findings: Of the 62 patients at the LTSC, 15 patients (24.2%) complained of olfactory or gustatory deterioration on admission. Four of 10 patients who underwent functional evaluation did not have general symptoms and 2 patients were asymptomatic. The mean sQOD-NS and QOD-VAS scores were 13 ± 6 and 4.7 ± 3.6, respectively. The mean CC-SIT score was 8 ± 2. No patients showed anatomical abnormalities associated with olfactory dysfunction on endoscopic examination. The mean Likert scale score for function was 8 ± 2, and there were no abnormal lesions in the oral cavity of any patient. Interpretation: The prevalence of olfactory and gustatory dysfunction was 24.2% in mild COVID-19 patients. All patients had hyposmia due to sensorineural olfactory deterioration, which was confirmed using validated olfactory and gustatory evaluation methods and endoscopic examination. Olfactory and gustatory dysfunction may be characteristic indicators of mild COVID-19. Funding Statement: No funding. Declaration of Interests: The authors declare no competing interests. Ethics Approval Statement: This study protocol was approved by the Institutional Review Board of the Korea University Ansan Hospital (2020AS0122).

This study attempts to investigate the interaction effects of cross-media advertisement, media engagement, and fashion product type on product preference. Therefore, a 2 × 2 × 2 (media engagement : high vs. low) × (advertisement type: traditional vs. cross-media) x 2 (fashion product type: hedonic vs. utilitarian) mixed factorial design was employed to test the hypotheses. The subjects were 163 women in their 20s and 30s living in Seoul, Gyeonggi-do, Daejeon area. For data analysis, three-way ANOVA, analysis of simple interactions, and analysis of simple main impacts were conducted using the SPSS program. The results of this study were as follows. First, the results showed a significant interaction effect between media engagement and fashion product type. For hedonic fashion products, consumer’s preferred products with high media engagement over those with low media engagement. Second, a significant interaction effect between advertisement type and fashion product type was revealed. In case of utilitarian products, consumer’s preferred products advertised through traditional advertisements over those advertised through (cross-media advertisements;) hedonic products showed no difference in this regard. Third, high media engagement group revealed greater favorability for hedonic (than utilitarian) products, when they were exposed to cross-media ad. These results imply importance of an appropriate advertising strategy according to fashion product type and individual differences such as SNS media engagement.

Nutrient removal from artificial wastewater in autotrophic condition by the co-culture consortium of Scenedesmus dimorphus and nitrifiers was investigated. The batch experiments of co-culture, S. dimorphus- and nitrifiers-only treatments were conducted and compared for 9 days. As a result, the co-culture system showed enhancement in both nitrogen (N) and phosphorous (P) removal compared to each single culture. Especially, total N removal efficiency and P removal efficiency in co-culture reactor were enhanced 3.4 and 6.5 times compared to nitrifiers-only reactor, respectively. This result implies that post-treatment systems such as denitrification of nitrate and luxury uptake of P can be deducted by using the co-culture consortium of Scenedesmus dimorphus and nitrifiers. In addition, unlike nitrifiers-only reactor, the co-culture maintained high Dissolved Oxygen (DO) without external aeration. Thus it is suggested that co-culture of Scenedesmus dimorphus and nitrifiers is an efficient and economic method to removal nutrient from wastewater.

Heterotrophic nitrifying bacteria capable of denitrification under aerobic conditions, which are known as HN-AD species, were investigated. Instead of the isolation and subsequent cultivation of a pure HN-AD strain, the activated sludge obtained from the domestic wastewater treatment plant was enriched to enhance the fraction and activity of the indigenous HN-AD species by adding ammonium and organic carbon. The enriched culture showed both rapid ammonium removal at a rate of 13.3 mg-N/L/hr and nitrate removal at a rate of 12.3 mg-N/L/hr, which was higher than those for the pure HN-AD bacteria reported in the literature. On the contrary, the activated sludge that was not enriched showed insignificant nitrification and aerobic denitrification. These results implied that the selective enrichment procedure improved the fraction and/or activity of the HN-AD culture in the mixed biomass. Consequently, the enriched HN-AD culture from activated sludge could be a feasible alternative over the conventional BNR process.

The synergistic effects of a co-culture of Chlorella vulgaris (C. vulgaris) and activated sludge in Volatile Fatty Acids (VFAs) treatment were examined by constructing and comparing the performance of the three reactors (only algae, only activated sludge, coculture). As a result, the addition of the activated sludge stimulated the growth of C. vulgaris up to 2.6-fold, even though the initial algae concentration in the co-culture was only 30% of that in the only algae reactor. The treatment efficiency, which was indicated by the degradation of both the VFAs and nutrients, increased due to the symbiotic relationship of the co-culture of C. vulgaris and activated sludge. For the co-culture of algae and activated sludge, the propionate removal rate was enhanced by approximately 29.5- fold and 2.2-fold, respectively, compared to only algae and only sludge; the butyrate removal rate was also enhanced 6-fold and 1.5- fold, respectively. Both the NH4+–N and PO43––P removal rate of the reactor with the co-culture was approximately 2 times higher than that of the reactor with the only algae and only sludge. Within 88 h, the removal efficiency of the co-culture reactor reached 98.2%, whereas the removal efficiency was 59.3% and 49.8% for only algae and only sludge reactor, respectively.

There are differences in preference according to the brand signal explicitness when selecting fashion luxury brand, and the purpose of this study is to verify the moderating effects of self-construal and implicit theory in relation to those preferences. This study divided the experiment design into two mixed design studies: Study 1 and Study 2. The study 1 was composed of the following factors: brand signal explicitness(subtle vs. explicit signal) and self-construal(independent vs. interdependent self-construal). Study 2 was composed of the following factors: brand signal explicitness( subtle vs. explicit signal) and Implicit theory(entity vs. incremental theorist). Convenience sampling was conducted to find the subjects of study 1 and study 2. Study 1 analyzed data from 172 women in Seoul, Gyeonggi-do and Busan who prefer luxury brand, and study 2 used data from 138 women. The results of this study are as follows. 1) Independent self-construal primed group was shown to prefer subtle signal product to explicit signal product, whereas interdependent self-construal priming group preferred explicit signal product to subtle signal product. 2) The entity theorist to prefer explicit signal product to subtle signal product. On the other hand, the incremental theorist did not show significant difference in the preference between subtle and explicit signal products. Therefore, the results of the present study shown the importance of understanding consumers through the difference depending on consumer inclination and psychology, recommending preferred luxury brand according to the inclination of the target customers, and establishing segmented marketing strategy to captivate consumers with these various characteristics.

Three-dimensional (3D) N-doped open-porous carbon foam was fabricated using the simple procedure of calcining a melamine sponge. The properties of the fabricated carbon foam and its performance in microbial fuel cells (MFCs) using Shewanella oneidensis MR-1 (S. oneidensis) were compared with those of commercial graphite felt. The MFC with the carbon foam anode produced approximately 2 times higher power density than the commercial graphite felt. The superior performance of the as-prepared carbon foam in MFC was attributed to the higher surface area (687.19 m2 g−1) and open-porous scaffold structure. Moreover, the appearance of the hydrophilic functional groups such as CN–C, N–CO on the surface of the as-prepared carbon foam facilitated extracellular electron transfer, resulting in a decrease in charge transfer resistance and an increase in biocompatibility. Owing to the excellent biocompatibility, a large amount of microbial biomass colonized both the surface and inside the carbon foam, which helped enhance the performance of the MFC.

Although microalgae are considered as a promising feedstock for biofuels, cost-efficient harvesting of microalgae needs to be significantly improved. In this study, the use of electro coagulation as a more rapid flocculation method for harvesting a freshwater (Scenedesmus dimorphus) microalgae species was evaluated. The results showed that, electro coagulation was shown to be more efficient using an aluminum anode than using an iron anode. And optimum conditions of electro coagulation for harvesting Scenedesmus dimorphus were found. The optimum stirring speed was 100 rpm and optimum pH was 5. Furthermore, the current density which the fastest and highest recovery efficiency is achieved at , while the highest energy efficiency was achieved at . A the rapid and high recovery efficiency indicate that electro coagulation is a particularly attractive technology for harvesting microalgae.