• Title/Summary/Keyword: Mass changes

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TEMPORAL VARIATIONS OF THE GLOBAL SEISMIC PARAMETERS OF HD 49933 OVER A MAGNETIC CYCLE

  • Kim, Ki-Beom;Chang, Heon-Young
    • Journal of The Korean Astronomical Society
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    • v.54 no.4
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    • pp.129-137
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    • 2021
  • It has been established that the acoustic mode parameters of the Sun and Sun-like stars vary over activity cycles. Since the observed variations are not consistent with an activity-related origin, even Sun-like stars showing out-of-phase changes of mode frequencies and amplitudes need to be carefully studied using other observational quantities. In order to test whether the presumed relations between the global seismic parameters are a signature of the stellar activity cycle, we analyze the photometric light curve of HD 49933 for which the first direct detection of an asteroseismic signature for activity-induced variations in a Sun-like star was made, using observations by the CoRoT space telescope. We find that the amplitude of the envelope significantly anti-correlates with both the maximum frequency of the envelope and the width of the envelope unless superflare-like events completely contaminate the light curve. However, even though the photometric proxy for stellar magnetic activity appears to show relations with the global asteroseismic parameters, they are statistically insignificant. Therefore, we conclude that the global asteroseismic parameters can be utilized in cross-checking asteroseismic detections of activity-related variations in Sun-like stars, and that it is probably less secure and effective to construct a photometric magnetic activity proxy to indirectly correlate the global asteroseismic parameters. Finally, we seismically estimate the mass of HD 49933 based on our determination of the large separation of HD 49933 with evolutionary tracks computed by the MESA code and find a value of about 1.2M and a sub-solar metallicity of Z = 0.008, which agrees with the current consensus and with asteroseismic and non-asteroseismic data.

Comparison of Clinical Characteristics and Effects of Modified Jaw Thrust Maneuver During Drug-Induced Sleep Endoscopy (DISE) between Positional and Non-Positional Obstructive Sleep Apnea Patients

  • Moon, Ji Seung;Koo, Soo Kweon;Kim, Young Joong;Lee, Sang Hoon;Lee, Ho Byoung;Park, Geun Hyung;Lee, Sang Jun
    • Journal of Clinical Otolaryngology Head and Neck Surgery
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    • v.29 no.2
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    • pp.190-197
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    • 2018
  • Background and Objectives : Positional OSAS is characterized by an apnea-hypopnea index (AHI) score >5, which, while sleeping in the supine position, is double that in non-supine position. This study was performed to compare the clinical characteristics of positional OSAS and non-positional OSAS patients, and the effects of the modified jaw thrust maneuver during drug-induced sleep endoscopy (DISE) between positional OSAS and non-positional OSAS patients. Materials and Methods : 68 positional OSAS patients and 19 non-positional OSAS patients were included. They all underwent full-night polysomnography and DISE. The modified jaw thrust maneuver was introduced during DISE. Airway structural changes induced by the modified jaw thrust maneuver were evaluated and documented. Results : There were no statistically significant differences in Friedman stage or tonsil grade, body mass index, Epworth sleepiness scale (ESS) score, blood pressure, AHI, or obstructive pattern between the positional and non-positional OSAS patients. However, mean arterial oxygen saturation (SaO2), lowest SaO2, and total arousal index values were more severe in the non-positional OSAS patients. After introduction of the modified jaw thrust maneuver, retrolingual level obstruction showed a tendency toward a higher rate of airway opening in positional OSAS patients than in non-positional OSAS patients. Conclusions : The effects of a mandibular advancement device (MAD) can be estimated by carrying out a modified jaw thrust maneuver during DISE. The tendency toward a higher rate of airway opening in positional OSAS patients than non-positional OSAS patients in retrolingual level obstruction after jaw thrust maneuver introduced during DISE may be clinically important for MAD.

Daily walnut intake improves metabolic syndrome status and increases circulating adiponectin levels: randomized controlled crossover trial

  • Hwang, Hyo-Jeong;Liu, Yanan;Kim, Hyun-Sook;Lee, Heeseung;Lim, Yunsook;Park, Hyunjin
    • Nutrition Research and Practice
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    • v.13 no.2
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    • pp.105-114
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    • 2019
  • BACKGROUND/OBJECTIVES: Several previous studies have investigated whether regular walnut consumption positively changes heart-health-related parameters. The aim of this study was to investigate the effects of daily walnut intake on metabolic syndrome (MetS) status and other metabolic parameters among subjects with MetS. SUBJECTS/METHODS: This study was a two-arm, randomized, controlled crossover study with 16 weeks of each intervention (45 g of walnuts or iso-caloric white bread) with a 6 week washout period between interventions. Korean adults with MetS (n = 119) were randomly assigned to one of two sequences; 84 subjects completed the trial. At each clinic visit (at 0, 16, 22, and 38 weeks), MetS components, metabolic parameters including lipid profile, hemoglobin A1c (HbA1c), adiponectin, leptin, and apolipoprotein B, as well as anthropometric and bioimpedance data were obtained. RESULTS: Daily walnut consumption for 16 weeks improved MetS status, resulting in 28.6%-52.8% reversion rates for individual MetS components and 51.2% of participants with MetS at baseline reverted to a normal status after the walnut intervention. Significant improvements after walnut intake, compared to control intervention, in high-density lipoprotein cholesterol (HDL-C) (P = 0.028), fasting glucose (P = 0.013), HbA1c (P = 0.021), and adiponectin (P = 0.019) were observed after adjustment for gender, age, body mass index, and sequence using a linear mixed model. CONCLUSION: A dietary supplement of 45 g of walnuts for 16 weeks favorably changed MetS status by increasing the concentration of HDL-C and decreasing fasting glucose level. Furthermore, consuming walnuts on a daily basis changed HbA1c and circulating adiponectin levels among the subjects with MetS. This trial is registered at ClinicalTrials.gov as NCT03267901.

Factors Influencing Dietary Behaviors and Stress in Male and Female College Students (남녀대학생의 식행동과 스트레스 영향요인)

  • Seo, Eun-Young;Lee, Seung-Lim
    • Journal of the Korean Society of School Health
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    • v.31 no.3
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    • pp.186-195
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    • 2018
  • Purpose: This study was performed to investigate the dietary behaviors and stress-related factors among male and female college students. Methods: A total of 405 college students (male-195, female-210) were recruited, of whom a questionnaire-based survey was conducted. The study investigated the general characteristics, health-related factors, dietary behaviors, and stress-related factors of the respondents. Results: The body mass index was significantly higher in males. The rates of underweight and overweight were significantly different between male and female respondents. The scores for workout frequency, health concerns and health condition were significantly higher in males, while the score for watching TV & playing computer games was significantly higher in females. The scores for meal regularity, frequency of breakfast consumption, and smoking were significantly higher in males. Eating problems showed a significant difference between males and females. The biggest source of stress was social factors, followed by college study and individual factors and the most experienced stress-induced symptom was anxiety, followed by headache and stomachache. The most popular way to overcome stress was taking a rest, followed by drinking & smoking and outdoor activity. The most preferred food under stressful conditions were alcohol or beverages, followed by hot & spicy food and sweet food, which showed a significant difference between males and females. Conclusion: These results indicate that stress affects dietary behaviors, drinking, smoking, and health status. Stress not only changes dietary behaviors, but is also related to health status. Therefore, it is necessary to develop appropriate programs for emotional stability and stress relief targeting college students which provide continuous nutrition education focused on desirable dietary behaviors and nutritional aspects.

A Study on the Modal Parameters for Cable System of Bridge (교량 케이블시스템의 모드변수에 관한 연구)

  • Lee, Hyunchol;Jo, Yeong-hoon;Kim, Jinsoo;Park, Kyoungho
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.23 no.5
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    • pp.48-59
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    • 2019
  • In recent years, the type of bridge where cables such as suspension bridge and cable-stayed bridge are the main factors in the construction of long-range bridges has been soaring. The effects of cables on these structures are very large, and for structural analysis, it is necessary to study the cable and the structural changes according to the mode characteristics of the cables. In particular, cables are directly connected to camber adjustment, which conveys load effects on girders to tower, and are important components in the overall structure, and since the initial tension on the construction is compared with the tension over time, this study was conducted to help identify the condition of the bridge's aging and abnormalities. Therefore, in this study, the characteristics of the mode from the mode analysis through the impact hammer to the mass of the cable and the change in the length of the cable are analyzed.

Stability analysis of an unsaturated expansive soil slope subjected to rainfall infiltration

  • Qi, Shunchao;Vanapalli, Sai K.;Yang, Xing-guo;Zhou, Jia-wen;Lu, Gong-da
    • Geomechanics and Engineering
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    • v.19 no.1
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    • pp.1-9
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    • 2019
  • Shallow failures occur frequently in both engineered and natural slopes in expansive soils. Rainfall infiltration is the most predominant triggering factor that contributes to slope failures in both expansive soils and clayey soils. However, slope failures in expansive soils have some distinct characteristics in comparison to slopes in conventional clayey soils. They typically undergo shallow failures with gentle sliding retrogression characteristics. The shallow sliding mass near the slope surface is typically in a state of unsaturated condition and will exhibit significant volume changes with increasing water content during rainfall periods. Many other properties or characteristics change such as the shear strength, matric suction including stress distribution change with respect to depth and time. All these parameters have a significant contribution to the expansive soil slopes instability and are difficult to take into consideration in slope stability analysis using traditional slope stability analysis methods based on principles of saturated soil mechanics. In this paper, commercial software VADOSE/W that can account for climatic factors is used to predict variation of matric suction with respect to time for an expansive soil cut slope in China, which is reported in the literature. The variation of factor of safety with respect to time for this slope is computed using SLOPE/W by taking account of shear strength reduction associated with loss of matric suction extending state-of-the art understanding of the mechanics of unsaturated soils.

Transfiguration of intangible cultural assets due to activation of Folk Festival - Gangneung Danoje as the pivot - (민속축제 활성화에 따른 무형문화재의 변용 - 강릉단오제를 중심으로)

  • Hwang, Ru-Shi
    • Korean Journal of Heritage: History & Science
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    • v.36
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    • pp.299-312
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    • 2003
  • Gangneung Danoje does not only have the longest history but also is the largest folk festival in Korea. However, during its long history Gangneung Danoje has not always been the way as it is today. As records reveal, since the Chosun dynasty and through Japanese rule, it has gone through numerous variations and registration processes in order to become a national designated major intangible cultural asset. Especially after it has been appointed as a national major intangible cultural asset Gangneung Danoje has under gone through variety of transformations. First of the few changes is the citizen-lead characteristic. As Gangneung Cultulral Center took charge of Danoje this trait has become prominent. Hereby Chosun dynasty's government lead system has transformed into a civilian lead festival. Second alteration is the enormous scale of expansion and the variations of the characteristic of the festival because of it. Dano event has increased annually from 12 events in 1974 to 58 events by 1999. As the scale of Danoje enlarged the promoters found solutions by providing diversified events in order to satisfy peoples' various aspirations from the festival. However this solution lead to a diversion - from participating festival to a spectating festival. And the last change that occurred is the awareness of the need to develop Danoje into an international festival. This is rather a desire from the government than of the people. In 1994, Korea visiting year as an opportunity this consciousness grew active. For instance, the invitation of mass foreign folk performance in 1999 seems to conform to this policy. The intention to make Gangneung Danoje not only to represent Gangneung but also to represent Korea's folk event can be witnessed. As we enter 21st Century this inclination for international festival has strengthened. Gangneung government has shown enthusiasm to find the future of Danoje by inviting external service corps to assess Danoje. The current inclination appears to be increase its value as an international festival through UNESCO cultural property registration and having this as a foundation make Danoje become an international cultural tourist product. The judgment of this will be made after Gangneung International Folklore Festival 2004.

Cyber Attacks and Appropriateness of Self-Defense (사이버 공격과 정당방위의 당위성)

  • Shin, Kyeong-Su
    • Convergence Security Journal
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    • v.19 no.2
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    • pp.21-28
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    • 2019
  • The emergence of a hyper-connected-super-intelligence society, called the era of the Fourth Industrial Revolution, brought about a new change in the security environment. With ICT (Information Communication Technology) convergence and high-tech technologies introduced across the board, the person-centered driving force that moved the real space is replaced by the code-oriented cyberspace, and its dependency is constantly increasing. Paradoxically, however, these technological changes serve as another security vulnerability that threatens our society, and have brought about the justification for building a cyber defense system while simultaneously facing the opportunities and challenges brought by technology. In this study, the theory of self-defense was put forward on the basis of the theoretical basis for actively responding to the increasingly intelligent and mass-evolving cyberattacks, and firstly, the need to enact a cybersecurity law, secondly, and thirdly, the need to develop a response cooperation system with the U.S. and other cyber powers.

Effectiveness of worksite-based dietary interventions on employees' obesity: a systematic review and meta-analysis

  • Park, Seong-Hi;Kim, So-Young
    • Nutrition Research and Practice
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    • v.13 no.5
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    • pp.399-409
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    • 2019
  • BACKGROUND/OBJECTIVES: This study was designed to provide scientific evidence on the effectiveness of worksite-based dietary intervention to reduce obesity among overweight/obese employees. MATERIALS/METHODS: Electronic search was performed using Ovid Medline, Embase, Cochrane Library, and CINAHL databases. The keywords used were "obesity," "nutrition therapy," and "worksite." The internal validity of the randomized controlled trials (RCTs) was assessed using the Cochrane's Risk of Bias. Meta-analysis of selected studies was performed using Review Manager 5.3. RESULTS: A total of seven RCTs with 2,854 participants were identified. The effectiveness of dietary interventions was analyzed in terms of changes in weight, body mass index (BMI), total cholesterol, and blood pressure. The results showed that weight decreased with weighted mean difference (WMD) of -4.37 (95% confidence interval (CI): -6.54 to -2.20), but the effectiveness was statistically significant only in short-term programs < 6 months (P = 0.001). BMI also decreased with WMD of -1.26 (95% CI: -1.98 to -0.55), but the effectiveness was statistically significant only in short-term programs < 6 months (P = 0.001). Total cholesterol decreased with WMD of -5.57 (95% CI: -9.07 to -2.07) mg/dL, demonstrating significant effectiveness (P = 0.002). Both systolic (WMD: -4.90 mmHg) and diastolic (WMD: -2.88 mmHg) blood pressure decreased, demonstrating effectiveness, but with no statistical significance. CONCLUSIONS: The worksite-based dietary interventions for overweight/obese employees showed modest short-term effects. These interventions can be considered successful because weight loss was below approximately 5-10 kg of the initial body weight, which is the threshold for the management of obesity recommended by the Scottish Intercollegiate Guideline Network (SIGN).

Effect of fermented spent instant coffee grounds on milk productivity and blood profiles of lactating dairy cows

  • Choi, Yongjun;Rim, Jongsu;Lee, Honggu;Kwon, Hyunchul;Na, Youngjun;Lee, Sangrak
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.7
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    • pp.1007-1014
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    • 2019
  • Objective: This study was conducted to evaluate the fermentation characteristics under low mesophilic temperature of spent instant coffee ground (SICG) and to estimate the effect of fermented SICG (FSICG) as alternative feed ingredient on milk productivity of dairy cows. Methods: In the fermentation trial, fermentation of SICG was performed to investigate changes in characteristics using the microbial mixture (Lactobacillus plantarum, Saccharomyces cerevisiae, and Bacillus subtilis = 1:1:1) for 21 days at $20^{\circ}C$ under anaerobic conditions. Molasses was added at 5% of dry mass. In the animal trial, eighteen Holstein Friesian cows were used to evaluate the nutritive value of the FSICG which was fermented for 14 days under the same condition as the fermentation trial. Results: In the fermentation trial, the dry matter (DM) and organic matter content linearly decreased with fermentation time (p<0.001 and p = 0.008, respectively). The acid detergent insoluble nitrogen content linearly decreased with fermentation time (p = 0.037). The microorganism counts linearly increased for Lactobacillus plantarum, Saccharomyces cerevisiae, and Bacillus subtilis across fermentation time (p<0.001). In the animal trial, the DM intake of the control and FSICG treatment were not significantly different, as were milk yield, 4% fat corrected milk, fat-protein corrected milk, and feed to milk conversion content. Fat, protein, lactose, non-fat solids, milk urea nitrogen, and somatic cell counts were also not significantly different in milk composition between treatments. Conclusion: FSICG should be considered a sufficient substitute for cottonseed as a feed component, and 5% DM of a dietary FSICG level was appropriate for dairy cow diets.